Hand truck World

Disclosed are an improved pneumatic wheels device for simulating the appearance of a larger-diameter wheel mounted within a low-profile pneumatic wheels. the pneumatic wheels system has an inboard side and an outboard side with a wide outer flange extending around the outer circumference of the pneumatic wheels system. The outer flange is preferably integral with the outboard face of the pneumatic wheels system. A design, preferably comprised of a plurality of protrusions, indentations, and slits, extends across at least a portion of the outboard face of the pneumatic wheels system, including the outboard face of the extended outer flange. In the improved pneumatic wheels, the outboard pneumatic wheels wall preferably includes a laterally extending wheel protector, a ledge, and a flange seat. The flange seat is preferably contoured to match the inner face of the outer flange of the improved wheel.

1. A pneumatic wheels device adapted to be attached to a vehicle, comprising:

(a) the pneumatic wheels system comprising:

(i) a central hub adapted to be attached to the vehicle, the central hub having an inboard side, an outboard side, and a central axis;

(ii) an inboard lip formed on the inboard side of the hub and extending radially outwardly;

(iii) an outer flange formed on the outboard side of the hub and extending radially outwardly, the outer flange having an inner diameter and an outer diameter, the outer diameter being greater than an outer diameter of the inboard lip, and the outer flange having an inboard side and an outboard side;

(iv) a design on the central hub that extends across at least a portion of the outer flange of the pneumatic wheels system, the distance between the central axis of the hub to the furthest radial extent of the design being greater than the distance between the central axis of the hub and the outer diameter of the inboard lip;

(b) the pneumatic wheels comprising:

(i) an inboard pneumatic wheels wall having an inner diameter, an outer diameter, and an inboard bead;

(ii) an outboard pneumatic wheels wall having an inner diameter, an outer diameter, and a flange seat, the flange seat having an outboard bead and a ledge, the radial distance between the inner and outer diameters of the inboard pneumatic wheels wall being approximately equal to the radial distance between the inner and outer diameters of the outboard pneumatic wheels wall;

wherein the pneumatic wheels is mounted on the pneumatic wheels system such that the inboard side of the outer flange substantially overlaps, and is in close proximity with, the flange seat, the outer radial edge of the outer flange is juxtaposed in substantially facing relationship with the pneumatic wheels ledge, the inboard lip interfaces with the bead of the pneumatic wheels, the area of interface between the outer flange of the pneumatic wheels system and the flange seat on the outboard pneumatic wheels wall is substantially greater than the area of interface between the inboard lip and the bead on the inboard pneumatic wheels wall, the outer flange extends radially outwardly no more than about halfway between the inner and outer diameters of the outboard pneumatic wheels wall and at least a portion of the outboard pneumatic wheels wall extends farther in the outboard direction than the outboard face of the outer flange, so as to give an appearance of a larger-diameter wheel mounted within a lower-profile pneumatic wheels.

2. The pneumatic wheels device of claim 1, wherein the outer diameter of the outer flange is at least about 1/4 inch greater than the outer diameter of the inboard lip.

3. The pneumatic wheels device of claim 1, wherein the outer diameter of the outer flange is at least about 3/4 inch greater than the outer diameter of the inboard lip.

4. The pneumatic wheels device of claim 1, wherein the outer diameter of the outer flange is at least about 11/4 inch greater than the outer diameter of the inboard lip.

5. The pneumatic wheels device of claim 1, wherein the outer diameter of the outer flange is at least about 13/4 inch greater than the outer diameter of the inboard lip.

6. The pneumatic wheels device of claim 1, wherein the outer flange is adapted to abut against the outer wall of the pneumatic wheels with substantially no gap therebetween when mounted thereon after the pneumatic wheels is pressurized.

7. The pneumatic wheels device of claim 1, wherein the central hub comprises a plurality of spokes and the pattern on the outer flange gives the appearance that the spokes extend across at least a portion of the outer flange.

8. The pneumatic wheels device of claim 1, wherein the difference between the inner diameter of the outboard pneumatic wheels wall and the outer diameters of the outer flange is at least about 2 inches.

9. The pneumatic wheels device of claim 1, wherein the difference between the inner diameter of the outboard pneumatic wheels wall and the outer diameters of the outer flange is at least about 21/2 inches.

10. The pneumatic wheels device of claim 8, wherein the outer flange is at least about twice as wide as the inboard lip.

11. The pneumatic wheels device of claim 1, further comprising a wheel protector formed on the outboard pneumatic wheels wall.

12. The pneumatic wheels device of claim 1, wherein the ledge has an inboard edge, an outboard edge, and a width therebetween, the width of the ledge being at least about 1/8 inch, and the ledge being substantially parallel with the central axis of the pneumatic wheels system.

13. The pneumatic wheels device of claim 1, wherein the inboard and outboard walls of the pneumatic wheels are not symmetrical.

14. A pneumatic wheels device adapted to be attached to a vehicle, comprising:

(a) the pneumatic wheels system comprising:

(i) a central hub adapted to be attached to the vehicle, the central hub having an inboard side, an outboard side, and a central axis;

(ii) an inboard lip formed on the inboard side of the hub and extending radially outwardly;

(iii) an outer flange formed on the outboard side of the hub and extending radially outwardly, the outer flange having an inner diameter and an outer diameter, the outer diameter being greater than an outer diameter of the inboard lip, and the outer flange having an inboard side and an outboard side;

(iv) a design on the central hub that extends across at least a portion of the outer flange of the pneumatic wheels system, the distance between the central axis of the hub to the furthest radial extent of the design being greater than the distance between the central axis of the hub and the outer diameter of the inboard lip; and

(b) the pneumatic wheels comprising:

(i) an inboard pneumatic wheels wall having an inner diameter, an outer diameter, and a width therebetween;

(ii) an outboard pneumatic wheels wall having an inner diameter, and outer diameter, and a width tberebetween, the widths of the inboard and outboard pneumatic wheels walls being approximately equal;

wherein the pneumatic wheels is mounted on the pneumatic wheels system such that an area of interface between the outer flange of the pneumatic wheels system and the outboard pneumatic wheels wall is substantially greater than an area of interface between the inboard lip and the inboard pneumatic wheels wall, and the outer radial edge of the outer flange is juxtaposed in substantially facing relationship with at least a portion of the outboard pneumatic wheels wall, the outer flange extends radially outwardly no more than about halfway between the inner and outer diameters of the outboard pneumatic wheels wall, and at least a portion of the outboard pneumatic wheels wall extends farther in the outboard direction than the outboard face of the outer flange, so as to give an appearance of a larger-diameter wheel mounted within a lower-profile pneumatic wheels.

15. The pneumatic wheels device of claim 14, wherein the outer diameter of the outer flange is at least about 1/4 inch greater than the outer diameter of the inboard lip.

16. The pneumatic wheels device of claim 14, wherein the outer diameter of the outer flange is at least about 13/4 inch greater than the outer diameter of the inboard lip.

17. The pneumatic wheels device of claim 14, wherein the outer flange is adapted to abut against the outer wall of the pneumatic wheels with substantially no gap therebetween when mounted thereon after the pneumatic wheels is pressurized.

18. The pneumatic wheels device of claim 14, wherein the central hub comprises a plurality of spokes and the pattern on the outer flange gives the appearance that the spokes extend across at least a portion of the outer flange.

19. The pneumatic wheels device of claim 14, wherein the difference between the inner and outer diameters of the outer flange is at least about 2 inches.

20. The pneumatic wheels device of claim 14, wherein the outer flange is at least about twice as wide as the inboard lip.

21. The pneumatic wheels device of claim 14, further comprising a wheel protector formed on the outboard pneumatic wheels wall.

This invention relates generally to pneumatic wheels and wheels for vehicles and in particular to pneumatic wheels and wheels for creating the appearance of low-profile pneumatic wheels mounted on large-diameter wheels.

2. Description of the Related Art

In recent years, consumer demand for large-diameter vehicle wheels mounted within low-profile pneumatic wheels has increased dramatically. Such wheels and pneumatic wheels create a stylish look for the vehicle on which they are used, but they cost much more than standard-sized wheels and pneumatic wheels. As a consequence, large-diameter wheels and low profile pneumatic wheels are desired by many consumers, but are beyond the financial reach of a large segment of the market. Moreover, most companies that make wheels are set up for mass production of wheels of certain standard sizes, and have often lagged behind consumer demand in developing or re-tooling expensive equipment, including molds and casting machinery, to produce the largest wheels desired by consumers.

Some consumers who want, but cannot afford or obtain, wheels with a sufficiently large diameter mounted within low profile pneumatic wheels may be willing to pay an intermediate cost to make standard-sized wheels and pneumatic wheels take on the appearance of the more expensive (and possibly unavailable) products. Detachable wheel extensions, such as the one shown in U.S. Patent Publication No. U.S. 2002/0079735 A1, have been used to attempt to simulate the appearance of larger wheels mounted within low-profile pneumatic wheels. However, such extensions mask a portion of the front face of the pneumatic wheels system and do not provide a surface integral with the design on the face of the pneumatic wheels system. Thus, the attempted simulation does not have a realistic-looking appearance.

In particular, the pneumatic wheels system extensions of the prior art have an inner ring that is removably secured within an inside edge of the outer lip of the existing wheel using a compression fit (as with a standard hub cap). A wide outer flange is attached to the inner ring and extends radially outwardly across a portion of the outside pneumatic wheels wall. the pneumatic wheels system extensions are intended to be used with many different types of wheels having a variety of surface designs on their front faces. The outward surfaces of the inner ring and outer flange generally have a smooth, generic appearance to attempt to aesthetically interface with all of these different designs. Although outer flanges of the prior art may include a narrow, upturned lip formed along the outer diameter of the flange and/or an undulated outward surface (e.g., a smooth stair-step pattern of concentric rings), the flanges do not include protrusions, indentations, or slits on their surfaces as are commonly found on the central portion of the front face of many wheels.

The inner ring for securing the pneumatic wheels system extension to the pneumatic wheels system is generally at least about 1/2 inch thick around its circumference, which covers up a significant portion of the underlying wheel face. When mounted on a wheel with a 17-inch diameter, a 1/2-inch thick ring makes the pneumatic wheels system appear to be only 16-inches in diameter. This results in a reduction of the visible surface area of the pneumatic wheels system by well over 10 percent. In addition, the smooth outward surfaces of the inner ring and outer flange generally do not blend in well with the existing design of the pneumatic wheels system. Indeed, the pneumatic wheels system extensions of the prior art are usually easily detectable by even a casual observer, and merely give the appearance of an over-extended add-on lip covering a portion of the outer pneumatic wheels wall. Thus, the attempted simulation is not only ineffective, it actually creates the opposite effect. Rather than simulating a larger wheel mounted within a low profile pneumatic wheels, the pneumatic wheels system extension gives the appearance of a smaller wheel mounted on a standard pneumatic wheels.

Moreover, the detachability of the pneumatic wheels system extension gives rise to additional problems. For example, wheel extensions are generally secured to wheels by providing compressible tabs which must be pressed with a tamping force within the outer lip of a standard wheel. The tabs sometimes bend or break during installation or when the pneumatic wheels system strikes another object, such as a sidewalk curb, causing the pneumatic wheels system extension to wobble or to fall off completely when the pneumatic wheels system turns.

The present invention provides an improved pneumatic wheels device for simulating the appearance of a larger-diameter wheel mounted within a low-profile pneumatic wheels. the pneumatic wheels system has an inboard side and an outboard side. The outboard side includes a wide outer flange which extends around the outer circumference of the pneumatic wheels system. The outer flange is preferably integral with the outboard face of the pneumatic wheels system and covers a substantial portion of the outboard wall of the pneumatic wheels within which the pneumatic wheels system is mounted. A design, preferably comprised of, for example, a plurality of protrusions, indentations, and slits, extends across at least a portion of the outboard face of the pneumatic wheels system, including the outboard face of the extended outer flange.

The improved pneumatic wheels of the present invention is intended to be mounted on the improved wheel of the present invention with an extended outer flange. The pneumatic wheels comprises an outboard pneumatic wheels wall, an inboard pneumatic wheels wall, and a tread therebetween. The outboard pneumatic wheels wall preferably includes a laterally extending wheel protector, a ledge, and a flange seat. The flange seat is preferably contoured to match the inner face of the outer flange of the pneumatic wheels system and is preferably more rigid than the remainder of the pneumatic wheels to prevent the pneumatic wheels from deflecting into the outer flange of the pneumatic wheels system under the load of a vehicle.

the pneumatic wheels system of the present invention may be mounted within a standard pneumatic wheels of the prior art or may be mounted within the pneumatic wheels of the present invention to produce a highly effective simulation of a larger-diameter wheel mounted with a low-profile pneumatic wheels.

A toe jack, comprising: a base member having a bottom surface and a base side wall peripherally disposed about said base member; a lift member having a top surface; a toe jack bellows disposed between said base member and said lift member, said bellows comprising a flexible member having an upper end a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber; and

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air.

2. The toe jack according to claim 1, wherein said base member further comprises a plurality of support members.

3. The toe jack according to claim 1, wherein said lift member further comprises a lift side wall peripherally disposed about said lift member.

4. The toe jack according to claim 1, wherein said lift member further comprises a plurality of support members.

5. The toe jack according to claim 1 further comprising a first connecting means for sealably connecting said upper end of said bellows to said top plate.

6. The toe jack according to claim 1 further comprising a second connecting means for sealably connecting said lower end of said bellows and said bottom plate.

7. The toe jack according to claim 1 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

8. The toe jack according to claim 7, wherein said valve means comprises pressure relief means for releasing air from said chamber when pressure in said chamber exceeds a predetermined amount.

9. The toe jack according to claim 1 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value.

10. The toe jack according to claim 9, wherein said venting means comprises at least one vent valve and an actuating member interconnecting said vent valve and an inner wall of said chamber.

11. The toe jack according to claim 10, wherein said vent valve is disposed in said top plate and pressurized air from said chamber is released peripherally between said top plate and said lift member to the atmosphere.

12. The toe jack according to claim 10, wherein said vent valve is disposed in said bottom plate and pressurized air from said chamber is released peripherally between said bottom plate and said base member to the atmosphere.

13. A toe jack, comprising:

a base member having a bottom surface and a plurality of support members;

a lift member having a top surface;

a bellows disposed between said base member and said lift member, said bellows comprising a flexible member having an upper end, a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber; and

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air.

14. The toe jack according to claim 13, wherein said lift member further comprises a lift side wall peripherally disposed about said lift member.

15. The toe jack according to claim 13, wherein said lift member further comprises a plurality of support members.

16. The toe jack according to claim 13 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

17. The toe jack according to claim 13 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprising at least one vent valve disposed in said top plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said top plate and said lift member.

18. The toe jack according to claim 13 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprises at least one vent valve disposed in said bottom plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said bottom plate and said lift member.

19. A toe jack, comprising:

a base member having a bottom surface;

a lift member having a top surface and a lift side wall, said lift side wall peripherally disposed about said lift member;

a bellows disposed between said base member and said lift member, said bellows comprising a flexible member having an upper end, a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber; and

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air.

20. The toe jack according to claim 19, wherein said lift member further comprises a plurality of support members.

21. The toe jack according to claim 19 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

22. The toe jack according to claim 19 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprising at least one vent valve disposed in said top plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said top plate and said lift member.

23. The toe jack according to claim 19 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprises at least one vent valve disposed in said bottom plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said bottom plate and said lift member.

24. A toe jack, comprising:

a base member having a bottom surface;

a lift member having a top surface and a plurality of support members;

a bellows disposed between said base member and said lift member, said bellows comprising a flexible member having an upper end, a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber; and

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air.

25. The toe jack according to claim 24 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

26. The toe jack according to claim 24 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprising at least one vent valve disposed in said top plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said top plate and said lift member.

27. The toe jack according to claim 24 further comprising venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprises at least one vent valve disposed in said bottom plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said bottom plate and said lift member.

28. A toe jack, comprising:

a base member having a bottom surface;

a lift member having a top surface;

a bellows disposed between said base member and said lift member, said bellows comprising a flexible member having an upper end, a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber;

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air; and

venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprising at least one vent valve disposed in said top plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said top plate and said lift member.

29. The toe jack according to claim 28, wherein said base member further comprises a base side wall and a plurality of support members, said base side wall peripherally disposed about said base member.

30. The toe jack according to claim 29, wherein said lift member further comprises a lift side wall peripherally disposed about said lift member.

31. The toe jack according to claim 30, wherein said lift member further comprises a plurality of support members.

32. The toe jack according to claim 28 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

33. A toe jack, comprising:

a base member having a bottom surface;

a lift member having a top surface;

a bellows disposed between said base member and said lift member, said

bellows comprising a flexible member having an upper end, a lower end and one or more convolutions disposed between said upper end and said lower end;

a top plate sealably connected to said upper end of said bellows and connected to said lift member;

a bottom plate sealably connected to said lower end of said bellows and connected to said base member, said top plate, said bellows and said bottom plate forming a pressurizable chamber;

inlet means in communication with said chamber for admitting pressurized air into said chamber to raise said lift member relative to said base member and for withdrawing pressurized air from said chamber to lower said lift member, said inlet means suitable for connection to a source of pressurized air; and

venting means in communication with said chamber for releasing air from said chamber whenever pressure therein exceeds a predetermined value, said venting means comprises at least one vent valve disposed in said bottom plate and an actuating member interconnecting said vent valve and an inner wall of said chamber, said vent valve configured to release pressurized air from said chamber to the atmosphere peripherally between said bottom plate and said lift member.

34. The toe jack according to claim 33, wherein said base member further comprises a base side wall and a plurality of support members, said base side wall peripherally disposed about said base member.

35. The toe jack according to claim 34, wherein said lift member further comprises a lift side wall peripherally disposed about said lift member.

36. The toe jack according to claim 35, wherein said lift member further comprises a plurality of support members.

37. The toe jack according to claim 33 further comprising valve means disposed between said inlet means and said source of pressurized air for controlling the admittance of pressurized air into said chamber and the withdrawal of pressurized air from said chamber.

1. Field of the Invention

The field of the present invention relates generally to devices for use in lifting objects. In particular, the present invention relates to portable pneumatically-operated lifting devices. Even more specifically, the present invention relates to low profile portable toe jacks that utilize one or more pressurizable bellows.

2. Background

The most commonly available jacking system currently used today are mechanical jacking devices that require the user to place the jack under the object to be lifted, such as one side or end of a motor vehicle, and mechanically operate the jack to extend the lifting axis and raise the object. Mechanical jacking devices have a number of commonly known disadvantages, including lack of stability and strength and the requirement of mechanical effort on part of the user. Another disadvantage of mechanical lifting devices is the amount of space required for the user to effectively utilize the mechanical jack. The space requirement limits the usefulness of these devices in situations where there is not much room for the user to operate the mechanical jack.

toe jacks overcome many of the limitations of mechanical jacking devices and are commonly used to lift various objects in many different situations. A number of such jacks are portable to allow use at locations other than at fixed facilities, such as repair workshops or garages. One common use for portable toe jacks is to lift one side or end of a motor vehicle or trailer off the ground surface to enable a person to replace a damaged tire or get under the motor vehicle to perform other repair work. For such use, the unextended toe jack must have a low profile to allow the user to easily place the jack under the disabled vehicle. Once placed under the portion of the vehicle the user desires to raise, air or hydraulic fluid is directed toward the jack to extend it and raise the vehicle. In general, toe jacks are suitable for lifting relatively heavy objects without requiring an undue amount of space or effort on part of the jack user.

A number of low profile toe jacks are known. The known toe jacks generally utilize a telescopically extendable lifting axis that extends in response to the introduction of air or hydraulic fluid into the jack. These type of jacks have a number of disadvantages, including known problems with the telescopic member sticking or even jamming during lifting or lowering operations.

toe jacks that rely on a telescoping member to obtain the desired lift have an inherent limit on the maximum amount of lift that can be obtained. The maximum lift of these type of toe jacks is limited by the design of the telescoping member. A toe jack that relies on flexible bellows for lift, such as the present invention, is not so limited. Although this could have some benefits in certain situations, the ability of the jack to obtain very high lift can result in an overturned vehicle or other object that is being lifted. To prevent over-filling and the potential for such problems, toe jacks often incorporate an automatic pressure release valve that vents pressurized air to the atmosphere. Unfortunately, persons have been known to attempt to overcome the JACK automatic pressure release valves (i.e., by blocking the release port or other means) in order to obtain lift that is outside the range in which the toe jack is designed.

3. Related Art

A number of related art devices exist that identify themselves as pneumatic or air-controlled lift devices. Such devices include U.S. Pat. No. 3,730,481 to Ekonen, U.S. Pat. No. 3,743,248 to Moor, U.S. Pat. No. 3,751,007 to Hollerith, U.S. Pat. No. 3,993,286 to Greene, U.S. Pat. No. 4,021,018 to Dasan, and U.S. Pat. No. 4,913,402 to McJunkin. None of these related art devices solve the problems identified and solved by the present invention in the manner solved by the present invention. Each of the aforementioned patents present toe jacks that utilize a telescoping member. Only the Moor patent discloses the use of a bellows in conjunction with a low profile, portable toe jack. The rubber bellows in the Moore patent, shown as 28 in FIG. 1 therein, merely serves as a casing to enclose the telescoping member and protect it against soiling and damage.

SUMMARY OF THE INVENTION

The toe jack of the present invention solves the problems identified above. That is to say, the present invention provides a low profile, portable toe jack utilizing a flexible bellows that extends in response to the introduction of air from a source of compressed air outside the jack to raise an object off a surface. The object is lowered by releasing air from the bellows. The toe jack of the present invention utilizes multiple safety systems to prevent over-extension of the bellows that could result in damage to the toe jack or overturning of the object being lifted (i.e., a motor vehicle).

In the primary embodiment of the present invention, the toe jack comprises a bellows made from a reinforced flexible member having at least one convolution (i.e., the part of the flexible member that forms an annular protrusion larger than the outside diameter of the ends of the bellows) therein. The bellows is located between a lift member that abuts the object to be lifted and a base member that abuts the surface from which the object is being lifted. The bellows is connected to the lift member and base member by a top plate and bottom plate, respectively, that sealably connect to the bellows through use of a connecting member at each plate. When configured, the bellows provides an air-tight chamber that expands or contracts with the introduction or release of pressurized air from within the chamber. A valve assembly controls the introduction and release of air from an outside pressure source, such as an air compressor or equivalent. A safety valve system prevents over-extension of the bellows.

The bellows can be made from any number of available rubber or polymer materials that can be reinforced with various fiber, steel or other strengthening materials that allows the flexible member to extend while

maintaining peripheral strength in the bellows. Bellows suitable for use in the toe jack of the present invention can include those commonly available as air springs. The ends of the bellows sealably attach to top and lower plates that form the pressurizable chamber.

The valve assembly comprises a fitting that provides communication between an external source of pressurized air and the chamber formed by the bellows. The fitting can connect to an air line that is suitable for transmitting pressurized air from the air source. A spring-controlled dual valve assembly is disposed between the source of air and the fitting to control the flow of air into the chamber and the release of air from the chamber. The dual valve assembly comprises a safety system to prevent over-pressurizing of the chamber by preventing the air pressure inside the chamber from exceeding a predetermined level.

Inside the chamber formed within the bellows, the toe jack can comprise a safety system that prevents over-filling, and therefore over-extension, of the bellows. In the preferred embodiment, the safety system comprises a pop-type valve in the top plate or the bottom plate, or both. When the bellows extends to the design limit, based on the construction of the toe jack itself and the need to prevent the motor vehicle or other object from overturning, the pop valve activates to release air from the pressurized chamber. In the preferred embodiment, the air exits the chamber through one or more passageways that allow air to be released peripherally between the lift member and the top plate and/or between the base member and the bottom plate. Air exiting in the manner described above provides relatively rapid release of air and prevents the user from blocking a single exit port in an attempt to obtain additional lift from the toe jack.

Accordingly, the primary objective of the present invention is to provide a toe jack that utilizes pressurized air to lift heavy loads having the features generally described above and more specifically described below in the detailed description.

It is also an important objective of the present invention to provide a portable toe jack that has a low profile when not pressurized. It is also an important objective of the present invention to provide a toe jack that is of durable, extremely sturdy construction having substantially high lift capacity.

It is also an important objective of the present invention to provide a toe jack that utilizes a bellows made of a flexible member that forms a pressurizable chamber in conjunction with top and bottom plates.

Yet another important objective of the present invention is to provide a toe jack that has one or more safety systems to prevent over-filling and over-extension of the toe jack wherein at least one of those safety systems is not able to be by-passed by the user of the jack.

It is a further objective of the present invention to provide a toe jack having a dual valve assembly that facilitates filling and release of air from a pressurizable chamber while preventing any over-filling or over-extension of the jack.

The above and other objectives of the present invention will be explained in greater detail by reference to the attached figures and the description of the preferred embodiment which follows. As set forth herein, the present invention resides in the novel features of form, construction, mode of operation and combination of parts presently described and understood by the claims.

A stable toe jack comprising a base adapted to be supported by the ground, an elongated piston extending from the base and defining an axis, a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston and having a fluid inlet in the inner surface adjacent the closed end, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, and supporting means for supporting the toe housing on the piston for movement relative to the piston along the piston axis, the supporting means including interengaging means on the inner surface of the toe housing and on the piston for preventing rotation of the toe housing relative to the piston about the axis, the supporting means including an upper bushing fixed to the piston, and a lower bushing fixed to the toe housing and having there through a bore surrounding and slidably engaging the piston, the lower bushing and the inner surface of the toe housing defining an expandable cavity communicating with the fluid inlet.

2. A toe jack as set forth in claim 1 wherein the interengaging means includes a keyway that is located in the inner surface of the toe housing and that extends in the direction of the axis, and a key that is fixed to the piston and that extends into the keyway.

3. A toe jack as set forth in claim 2 wherein the lower bushing sealingly engages the piston.

4. A toe jack as set forth in claim 1 wherein the interengaging means includes a keyway that is located in the piston and that extends in the direction of the axis, and a key that is fixed to the inner surface of the toe housing and that extends into the keyway.

5. A toe jack as set forth in claim 1 wherein the inner surface of the toe housing includes a first portion having a longitudinally extending recess and a second portion that is adjacent the open end of the toe housing.

6. A toe jack as set forth in claim 5 wherein the inner surface of the toe housing has a step extending radically between the first portion of the inner surface and the second portion of the inner surface, and wherein radial extent of the step is greater than the radial extent of the recess.

7. A toe jack as set forth in claim 1 wherein the piston has a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends, wherein a portion of the inner surface of the toe housing is spaced from the outer surface of the piston and is non-circular in a plane perpendicular to the piston axis, and wherein the supporting means includes a bushing fixed to the piston adjacent the distal end and having a peripheral surface that is sized and configured to slidingly mate with the non-circular portion of the inner surface of the toe housing.

8. A toe jack as set forth in claim 1 wherein the lower bushing is seemingly engaged with the piston.

9. A toe jack as set forth in claim 1 wherein the piston has a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends, wherein a portion of the outer surface of the piston and is non-circular in a plane perpendicular to the piston axis, and wherein the supporting means includes a bushing fixed to the toe housing and having therethrough a non-circular bore that slidingly engages the non-circular portion of the outer surface of the piston.

10. A toe jack as set forth in claim 1 wherein the piston has an outer surface cantered on the axis defined by the piston, and wherein the supporting means includes a bushing fixed to the piston and having an outer surface engaged with a portion of the inner surface of the toe housing, the outer surface of the bushing that is fixed to the piston and the portion of the inner surface of the toe housing that is engaged by the bushing fixed to the piston both being centered on an axis that is offset from the axis defined by the piston.

11. A toe jack as set forth in claim 1 and further comprising a pump assembly removably mounted on the toe housing, the pump assembly including a reservoir adapted to contain a supply of fluid and a fluid passage communicable with the reservoir and adapted to communicate with the fluid inlet.

12. A toe jack as set forth in claim 11 wherein the toe housing includes a fluid outlet passage communicable with the cavity and further including an outlet valve on the toe housing for opening and closing the fluid outlet passage, the outlet valve being operable when used either with the pump assembly or when used with an alternative high-pressure fluid supply.

13. A toe jack as set forth in claim 1 and further including a remote source adapter irremovably mounted on the toe jack and adapted to be connected to a source of high pressure fluid.

14. A toe jack comprising

a base assembly including an elongated piston defining an axis,

a generally cylindrical toe housing supported by the piston for movement relative to the piston along the axis, the toe housing and the piston defining an expandable cavity, and the toe housing having extending therein a fluid inlet passage communicating with the expandable cavity,

a fluid source attachment including a fluid reservoir adapted to contain a fluid supply, a fluid passage communicable with the reservoir and communicating with the fluid inlet passage and a hand pump operable to cause a flow of fluid from the reservoir through the fluid passage into the cavity, and

mounting means for removably supporting the fluid source attachment on the toe housing to afford fluid communication between the fluid passage and the fluid inlet passage and alternatively to afford ready removal of the fluid source attachment and to permit fluid communication between the fluid inlet passage and an alternative high-pressure fluid supply.

15. A toe jack as set forth in claim 14 wherein the toe housing has extending therethrough a fluid outlet passage communicable with the cavity, and wherein the toe housing includes an outlet valve for selectively opening and closing the fluid outlet passage to control flow of hydraulic fluid, the outlet valve remaining with the toe housing when the pump assembly is removed from the toe housing.

16. A toe jack as set forth in claim 14 wherein the mounting means includes a port adapter extending between the fluid inlet passage and the fluid passage in the fluid source attachment when the fluid source attachment is mounted on the toe housing.

17. A jack as set forth in claim 14 wherein the toe housing has extending therethrough a fluid outlet passage communicating with the cavity, wherein the fluid inlet passage and the fluid outlet passage respectively have a fluid inlet port and a fluid outlet port terminating at a mounting face on the exterior of the toe housing.

18. A toe jack as set forth in claim 17 wherein the fluid source attachment includes a mounting face having therein a fluid passage port communicating with the fluid passage and a reservoir port communicating with the reservoir, the mounting face on the pump assembly and the mounting face on the toe housing mating so that the fluid inlet port and fluid passage port register and so that the fluid outlet port and reservoir port register.

19. A toe jack as set forth in claim 18 wherein the fluid source attachment is a pump assembly.

20. A toe jack as set forth in claim 18 wherein the fluid source attachment is a remote source adapter.

21. A toe jack comprising

a base including an elongated piston,

a generally cylindrical toe housing supported by the piston for movement along a portion of the length of the piston, the toe housing and the piston defining therebetween an expandable cavity, and

a pump assembly mounted on the toe housing, the pump assembly including a fluid reservoir communicable with the cavity and adapted to contain a fluid supply and including a hand operable pump for pumping a flow of fluid from the reservoir to the cavity, the pump including a first handle that is moveable relative to the toe housing to pump fluid and a second handle that is selectively moveable relative to the first handle between a lifting position wherein the second handle prevents movement of the first handle relative to the toe housing and an operating position wherein the second handle affords movement of the first handle relative to the toe housing.

22. A toe jack comprising

a base adapted to be supported by the ground,

an elongated piston extending from the base and defining an axis,

a toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing and the piston defining there between an expandable cavity adapted to contain a supply of fluid under pressure,

means for supporting the toe housing for movement relative to the piston along the axis between a retracted position and an extended position, the means for supporting the toe housing including a first bushing fixed to the piston and a second bushing fixed to the toe housing,

interengaging means on the inner surface of the toe housing and on the piston for preventing rotation of the toe housing relative to the piston about the axis,

a seal sealingly fixed to the toe housing adjacent the open end of the toe housing and slidably sealingly engaged with the piston, and

a fluid inlet communicating with the cavity and adapted to communicate with a supply of fluid under pressure for moving the toe housing relative to the piston.

23. A toe jack comprising

a base adapted to be supported by the ground,

an elongated piston extending from the base and defining an axis,

a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface,

supporting means for supporting the toe housing on the piston for movement relative to the piston along the piston axis, the supporting means including interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a keyway in the piston that extends in the direction of the axis and a key that is fixed to the inner surface of the toe housing and that extends into the keyway and a bushing sealingly fixed to the piston and sealingly slidably engaging the inner surface of the toe housing.

24. A toe jack comprising

a base adapted to be supported by the ground,

an elongated piston defining a piston axis, the piston having a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends, a portion of the outer surface of the piston being non-circular in a plane perpendicular to the piston axis,

a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface,

interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a bushing fixed to the toe housing and having therethrough a non-circular bore that slidingly engages the non-circular portion of the outer surface of the piston, and

a bushing sealingly fixed to the piston and sealingly slidably engaging the inner surface of the toe housing.

25. A toe jack comprising

a base adapted to be supported by the ground,

an elongated piston defining a piston axis, the piston having a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends and being centered on the piston axis,

a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the inner surface of the toe housing having a first portion that is centered on the piston axis and a second portion that is centered on a second axis offset from the piston axis, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, and

interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a first bushing fixed to first portion of the inner surface of the toe housing and having therethrough a bore that sealingly slidingly engages the piston and a second bushing fixed to the piston and slidably engaging the second portion of the inner surface of the toe housing.

1. Technical Field

The invention relates to jacks for lifting loads, and more particularly to hydraulic toe jacks.

2. Related Prior Art

Toe jacks are used for lifting loads in general industrial applications such as the rigging of machinery, automotive maintenance and material handling, and in the maintenance of railroad rails and beds. A toe jack typically includes a base and a lifting surface or “toe” that is moveable to a retracted position wherein the toe is flush or closely spaced with the base. Because the toe can be positioned so as to be closely spaced to the base, toe jacks are well-suited for use in close quarters and in applications wherein the object to be lifted provides minimal clearance for the jack.

Toe jacks can be either hydraulically or mechanically operated and can be used to lift extremely heavy loads over a relatively small distance. Because of the mechanical advantages that can be realized by using hydraulic fluid as a medium for operating a toe jack, hand operable hydraulic toe jacks can be used to lift loads exceeding several tons. However, a toe jack that is subjected to such heavy loading, must contain and maintain relatively high hydraulic fluid pressures within the toe jack.

Since the introduction of concrete as a material used for railroad ties, toe jacks used for the maintenance and repair of railroad beds must have an increased lifting capacity. For example, a concrete tie may weigh approximately 800 lbs. whereas a wooden tie may weight approximately 200 lbs. However, it is desirable for such toe jacks to be relatively easily portable. Also, a toe jack subjected to heavy loading should remain stable as it extends to lift the load.

In general, the invention provides a relatively light weight, high capacity hydraulic toe jack that is well-suited for the maintenance and repair of railroad beds. The toe jack has few components, thereby providing a portable toe jack, and also has a relatively high lifting capacity.

In one embodiment, the invention provides a toe jack including a base adapted to be supported by the ground, an elongated piston extending from the base and defining an axis, a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, and supporting means for supporting the toe housing on the piston for movement relative to the piston along the piston axis, the supporting means including interengaging means on the inner surface of the toe housing and on the piston for preventing rotation of the toe housing relative to the piston about the axis and a bushing fixed to the toe housing and having therethrough a bore surrounding and slidably engaging the piston.

In another embodiment, the invention provides a toe jack including a base assembly including an elongated piston defining an axis, a generally cylindrical toe housing supported by the piston for movement relative to the piston along the axis, the toe housing and the piston defining an expandable cavity, and the toe housing having extending therein a fluid inlet passage communicating with the expandable cavity, a fluid source attachment including a fluid reservoir adapted to contain a fluid supply, a fluid passage communicable with the reservoir and communicating with the fluid inlet passage and a hand pump operable to cause a flow of fluid from the reservoir through the fluid passage into the cavity, and mounting means for removably supporting the fluid source attachment on the toe housing to afford fluid communication between the fluid passage and the fluid inlet passage and alternatively to afford ready removal of the fluid source attachment and to permit fluid communication between the fluid inlet passage and an alternative high-pressure fluid supply.

In another embodiment, the invention provides a toe jack including a base including an elongated piston, a generally cylindrical toe housing supported by the piston for movement along a portion of the length of the piston, the toe housing and the piston defining therebetween an expandable cavity, and a pump assembly mounted on the toe housing, the pump assembly including a fluid reservoir communicable with the cavity and adapted to contain a fluid supply and including a hand operable pump for pumping a flow of fluid from the reservoir to the cavity, the pump including a first handle that is moveable relative to the toe housing to pump fluid and a second handle that is selectively moveable relative to the first handle between a lifting position wherein the second handle prevents movement of the first handle relative to the toe housing and an operating position wherein the second handle affords movement of the first handle relative to the toe housing.

In another embodiment, the invention provides a toe jack including a base adapted to be supported by the ground, an elongated piston extending from the base and defining an axis, a toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing and the piston defining therebetween an expandable cavity adapted to contain a supply of fluid under pressure, means for supporting the toe housing for movement relative to the piston along the axis between a retracted position and an extended position, interengaging means on the inner surface of the toe housing and on the piston for preventing rotation of the toe housing relative to the piston about the axis, a seal sealingly fixed to the toe housing adjacent the open end of the toe housing and slidably sealingly engaged with the piston, and a fluid inlet communicating with the cavity and adapted to communicate with a supply of fluid under pressure for moving the toe housing relative to the piston.

In another embodiment, the invention provides a toe jack comprising a base adapted to be supported by the ground, an elongated piston extending from the base and defining an axis, a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, supporting means for supporting the toe housing on the piston for movement relative to the piston along the piston axis, the supporting means including interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a keyway in the piston that extends in the direction of the axis and a key that is fixed to the inner surface of the toe housing and that extends into the keyway and a bushing sealingly fixed to the piston and sealingly slidably engaging the inner surface of the toe housing.

In another embodiment, the invention provides a toe jack including a base adapted to be supported by the ground, an elongated piston defining a piston axis, the piston having a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends, a portion of the outer surface of the piston being non-circular in a plane perpendicular to the piston axis, a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a bushing fixed to the toe housing and having therethrough a non-circular bore that slidingly engages the non-circular portion of the outer surface of the piston, and a bushing sealingly fixed to the piston and sealingly slidably engaging the inner surface of the toe housing.

In another embodiment, the invention provides a toe jack including a base adapted to be supported by the ground, an elongated piston defining a piston axis, the piston having a first end fixed to the base, a second end spaced from the base and an outer surface extending between the first and second ends and being centered on the piston axis, a generally cylindrical toe housing having a closed end and an open end, the toe housing defining an inner surface surrounding a portion of the piston, the inner surface of the toe housing having a first portion that is centered on the piston axis and a second portion that is centered on a second axis offset from the piston axis, the toe housing being movable relative to the piston along the axis, and the toe housing including a toe projecting from the open end of the toe housing, the toe including a lifting surface, and interengaging means on the inner surface of the toe housing and the on piston for preventing rotation of the toe housing relative to the piston about the axis, the interengaging means including a first bushing fixed to first portion of the inner surface of the toe housing and having therethrough a bore that sealingly slidingly engages the piston and a second bushing fixed to the piston and slidably engaging the second portion of the inner surface of the toe housing.

A feature of the invention is the provision of a hydraulic toe jack that remains relatively stable under heavy loading. The toe jack includes a toe that cannot rotate relative to the base of the toe jack as the toe moves away from the base of the toe jack.

Another feature of the invention is the provision of a hydraulic toe jack having a simple construction and having hydraulic seals that are configured to contain hydraulic fluid under high pressure.

Another feature of the invention is the provision of a toe jack that is adapted to be operated with a hand operable pump assembly that can be mounted on the toe jack or alternatively operated by connecting the toe jack to another source of high pressure hydraulic fluid, such as a mechanically operated pump.

Another feature of the invention is the provision of a hydraulic toe jack including a carrying handle that is moveable into a carrying position to allow the jack to be lifted and carried and to prevent operation of the pump of the toe jack, and that is movable away from the carrying position to afford operation of the pump of the toe jack.

Another feature of the invention is the provision of a relatively light weight hydraulic toe jack that can be hand carried and that has a high lifting capacity.

Another feature of the invention is the provision of a hydraulic toe jack that is easily repaired and maintained. The toe jack includes a toe housing that is easily removable for repair and maintenance or replacement, even when the toe jack is located in the field. Also, the toe housing is made of a wear resistant material.

The present invention is machine jacks having a propping mechanism comprised of a prop attached parallel to and jointly movable with the lifting arm, a storage well for receiving the prop in a retracted position, and a pin engagable with the prop to bias the prop and the body of the jack to prevent untimely lifting arm retraction.

<<STMJ.C.U>>

1. Machine jacks comprising: a jack housing, a lifting arm, and a prop; said housing having an upper surface; said lifting arm attached to said housing; said lifting arm having a center axis; said prop being elongated and oriented generally parallel with, and adjacent to, said lifting arm; said lifting arm and said prop jointly movable along said lifting arm center axis; said lifting arm and said prop controllably extendable away from and retractable toward said housing upper surface; said prop having at least one pin receptacle adjacent to said lifting arm; and a pin selectively engagable with said at least one pin receptacle such that restrictive motion of said prop biases an engaged said pin between said upper surface and an engaged said at least one pin receptacle.

The machine jacks further comprising: said housing having a storage well for receiving said prop.

Machine jacks comprising: a jack housing, a lifting arm, and a prop; said housing having an upper surface; said lifting arm attached to said housing; said lifting arm having a centre axis; said prop attached to said lifting arm distal said jack housing; said prop being elongated and oriented generally parallel with, and adjacent to, said lifting arm; said lifting arm and said prop jointly controllably extendable away from and retractable toward said housing upper surface along said lifting arm centre axis; said prop having at least one pin receptacle; and a pin selectively engagable with said at least one pin receptacle such that restrictive motion of said prop biases an engaged said pin between said upper surface and an engaged said at least one pin receptacle.

The machine jacks wherein: said at least one pin receptacle being a transverse perforation in said prop.

The machine jacks wherein: said lifting arm telescopically attached to said housing; and said lifting arm extendable outwardly from said upper surface.

Machine jacks having a jacking mechanism, a jack base, a jack hot using, and a lifting arm, said safety jack comprising: said jack housing having a bottom and a top; said machine jack base attached to said jack housing bottom; said lifting arm having a centre axis; said lifting arm telescopically attached to said jack housing; a prop; said prop attached to said lifting arm distal said jack housing; said jacking mechanism having a lifting operation and a lowering operation, each consisting of movement along said lifting arm centre axis; said lifting arm and said prop jointly extendable outwardly from said jack housing top in said lifting operation; said lifting arm and said prop jointly retractable inwardly toward said jack housing top in said lowering operation; said housing having a storage well for receiving said prop; a pin; said prop having at least one pin receptacle for selectively receiving said pin; and each said pin receptacle configured to bias a selectively received said pin against said jack housing top in order to selectively disable said lowering operation.

A great variety of machine jacks are known in the field. Machine jacks are employed to lift items of substantial weight to include vehicles. In some instances, once an item is lifted it may be desired to maintain the item in the elevated position for an extended period while activity is conducted about the item. In these instances, there exists a hazard that the particular jack may lose lifting force engagement, permitting the weighty item to unexpectedly lower. This presents a particularly serious hazard to activity being conducted underneath the item. For this reason the field of art practices placing rigid supports or jack stands under items to prevent the item from lowering in case the jack loses lifting force.

The prior art possesses a variety of exemplary adjustable jacks and jack stands. The following are a few examples.

A machine jacks stand with a safety-locking device whereby a pin is positioned through a plurality of alienable corresponding holes in the shaft and the housing locking these members with respect to each other longitudinally. The pin is keyed so as to prevent withdrawal of the pin until rotated into an aligned position.

A jackable stand comprising of a vertical post that projects upward normal to a base. A carriage is attached to the vertical post moveably along the length of the post. The post has receiver holes vertically spaced apart along a length of the post and extending through the post. The carriage and base are engageable by a jack that may employ mechanical advantage to progress the carriage along the length of the post. A pin is employed in a selected receiver hole to restrict movement of the carriage along the post.

Machine jacks stand having a hydraulic bottle jack positionable on an elongated jack support comprising a tubular outer housing, a moveable cylindrical member, and a pin. The outer housing has a pin anchor receiver, such that the pin may be inserted through the outer housing. The moveable member has a plurality of receiver holes vertically spaced apart along a length that, with the moveable member inserted into the outer housing, may be selectively alignable with the anchor receiver such that the pin may be inserted through both a receiver hole and the anchor hole, fixing the outer housing and moveable member longitudinally.

A cabinet installation lifting system comprising a machine jack and a pair of extendable supports, wherein said supports each comprise a tubular outer housing having an pin anchor receiver, a moveable cylindrical member having a plurality of receiver holes vertically spaced apart along a length that, with the moveable member inserted into the outer housing, may be selectively alignable with the anchor receiver such that a pin may be inserted through both a receiver hole and the anchor hole, fixing the outer housing and moveable member longitudinally throughout the lifting range of the jack.

An adjustable machine jacks stand having a ratchet and pawl height maintenance mechanism with a pin and hole mechanism wherein the holes in the post coordinate with the teeth in the post so that any engagement between the pawl and a tooth ensures that a pair of holes in the base and the post are aligned to receive a pin.

It would be an improvement to the art to provide a machine jack having a locking mechanism comprised of a prop exterior to the lifting arm, a storage well for receiving the prop in a retracted position, and a locking pin engagable with said prop to bias said prop and the body of the jack to selectively prevent lifting arm retraction.

The invention is a machine jack having a housing, a lifting arm or ram, and a prop. The prop may comprise at least one segment extending from said bottle housing parallel with said ram. Another embodiment of a prop may be integrated into a lifting arm. The bottle housing comprises a storage area designed to receive the prop from the face from which the ram extends. A suitable storage area may comprise a well positioned around the circumference of the ram, having a width and depth suitable to receive the prop as the prop moves with the ram from an extended position primarily out of the well to a retracted position primarily contained in the well. The prop comprises at least one pin receptacle for engagement with a pin such that the engagement of said pin with said receptacle positions said pin to restrict retraction of said ram to within said housing by biasing between the engaged pin receptacle and the bottle housing adjacent to the outer edge of the well. In this manner such an inventive hydraulic jack may mechanically support a weight in an extended position, even if said machine jacks were to lose hydraulic support of said ram.

The machine jacks 10 is shown. Machine jacks 10 may be a hydraulic bottle jack having a generally cylindrical jack housing 12 fixedly attached to a solid jack base 18 at one end, generally considered the bottom of jack 10. Other types of jacks known in the art may employ the inventive device. In the exemplary embodiment, jacking mechanism 16 is adjacent and operable linked to jack housing 12. Operation of jacking mechanism 16 creates hydraulic pressure from mechanical leverage through hydraulic fluid (not shown) within a fluid reservoir 24 contained in jack housing 12; a device and process known to the art. Also known to the art is the employment of this pressurized hydraulic fluid to work against the one end of ram 14 recessed into jack housing 12 causing ram 14 to controllably extend away from and retract toward jack housing 12 with substantial force F having substantial lifting capacity. In this fashion ram 14 may be described as being telescopically attached to jack housing 12. A jack shoe 17 is provided on the opposite end of ram 14 from machine jack housing 12, generally considered the top of jack 10, to provide an interface surface to an item to be jacked (not shown), as known in the art.

The present invention enables waste to be removed from behind pneumatic wheels without having to remove the wheel from the compaction machine. The present compaction wheel allows access through the compaction wheel to a portion of the axle located behind the wheel, thereby saving the cost associated with removing the compaction wheel and improving productivity by reducing the amount of down time needed to service and inspect each compaction wheel, its axle and the portions of the compaction machine hidden by each wheel. Each compaction wheel includes an access opening disposed between a wheel hub and outer rim and operatively adapted to allow access to and permit removal of waste from around a portion of the axle located behind the compaction wheel, while the compaction wheel is mounted on the axle. The access opening can be of a sufficient size to allow the passage of the head and one or both arms of a worker therethrough and can also be operatively adapted to allow access through the front side of the compaction wheel to a portion of the axle located behind the wheel. A removable cover or hatch is mounted on each wheel so as to substantially close its access opening to prevent waste from passing through each access opening and accumulating behind each wheel, while the compaction machine is being operated.

1. pneumatic wheels for mounting on an axle of a compaction machine, said compaction wheel comprising:

a front side and a back side;

a waste entry site on said back side which provides a path for waste to enter an inner wheel space disposed between said compaction wheel and a portion of an axle of a compaction machine mounting said compaction wheel;

a hub operatively adapted for mounting on the axle of the compaction machine;

a rim disposed around and radially out from said hub; and

an access opening disposed between said hub and said rim, said access opening allowing access through said front side to said inner wheel space and permitting removal of waste trapped in said inner wheel space, while said compaction wheel is mounted on the axle.

2. pneumatic wheels as set forth in claim 1, wherein said access opening has an area of at least about 170 in2 (1097 cm2).

3. pneumatic wheels as set forth in claim 1, wherein said compaction wheel further comprises a removable cover mounted so as to substantially close said access opening.

4. pneumatic wheels as set forth in claim 3, wherein said compaction wheel further comprises a frame defining said access opening between said hub and said rim, and said cover is operatively adapted for being removably secured to said frame so as to substantially close said access opening.

5. pneumatic wheels for mounting on an axle of a compaction machine, said compaction wheel comprising:

a front side and a back side;

a waste entry site on said back side which provides a path for waste to enter an inner wheel space disposed between said compaction wheel and a portion of an axle of a compaction machine mounting said compaction wheel;

a hub operatively adapted for mounting on the axle of the compaction machine;

a rim disposed around and radially out from said hub;

an access opening disposed between said hub and said rim, said access opening allowing access through said front side to said inner wheel space and permitting removal of waste from between a portion of the axle and said compaction wheel, while said compaction wheel is mounted on the axle; and

a removable cover mountable to substantially close said access opening.

6. pneumatic wheels as set forth in claim 5, wherein said rim includes an outer wrapper on which a plurality of cleats are mounted.

7. pneumatic wheels as set forth in claim 5, wherein said compaction wheel further comprises an intermediatestructure between said hub and said rim which includes a frame defining said access opening, and said cover is operatively adapted for being removably secured to said frame so as to substantially close said access opening.

8. pneumatic wheels as set forth in claim 7, wherein said intermediate structure is annular shaped and further comprises two semi-circular plates that are generally parallel to one another and interconnected between said hub and said rim, each of said semi-circular plates has two ends, and said access opening is disposed between the ends of said semi-circular plates.

9. A compaction machine comprising:

a vehicle having a body and at least one axle mounting at least one compaction wheel, said compaction wheel comprising:

a front side and a back side, with said back side facing said body,

a waste entry site on said back side which provides a path for waste to enter an inner wheel space disposed between said compaction wheel and a portion of an axle of a compaction machine mounting said compaction wheel,

a hub operatively adapted for being mounted on said axle,

a rim disposed around and radially out from said hub,

an access opening disposed between said hub and said rim, said access opening allowing access through said front side of said compaction wheel to remove waste from between said back side of said compaction wheel and said vehicle body, while said compaction wheel is mounted on said axle, and

a removable cover mounted to substantially close said access opening.

10. The compaction machine as set forth in claim 1, wherein said at least one compaction wheel is two compaction pneumatic wheels, one mounted on either end of said axle.

11. The compaction machine as set forth in claim 9, wherein said at least one compaction wheel is four compaction pneumatic wheels, said at least one axle is two axles, and each of said axles mounts two of said compaction pneumatic wheels.

12. The compaction machine as set forth in claim 11, wherein said axles include a first axle, said compaction pneumatic wheels include two first compaction pneumatic wheels mounted on said first axle, and said compaction machine includes a dozer blade mounted on two pivot arms disposed outside of said first compaction pneumatic wheels so as to block the removal of said first compaction pneumatic wheels from said first axle.

13. The compaction machine as set forth in claim 9, wherein said compaction machine further comprises a trap system for effectively reducing the size of said waste entry site and trapping waste outside of said inner wheel space.

14. The compaction machine as set forth in claim 13, wherein said axle is mounted for rotation inside an axle housing, and said trap system comprises an annular plate mounted around the outside of said axle housing, said annular plate is disposed adjacent to the back side of said compaction wheel so as to effectively reduce the size of said waste entry site.

15. The compaction machine as set forth in claim 14, wherein said rim has a back side, and an annular ring is mounted on said annular plate between the back side of said rim and said annular plate so as to further reduce the effective size of said waste entry site.

16. The compaction machine as set forth in claim 14, wherein said rim has a back side, the back side of said rim has an inside diameter surface, and an annular ring is mounted on said annular plate adjacent to said inside diameter surface so as to further reduce the effective size of said waste entry site.

17. The compaction machine as set forth in claim 14, wherein said rim has a back side, the back side of said rim has an inside diameter surface, and a first annular ring and a second annular ring are mounted on said annular plate, one ring between the back side of said rim and said annular plate and the other ring adjacent to said inside diameter surface, so as to further reduce the effective size of said waste entry site.

18. A compaction machine comprising:

a vehicle having a body, at least one axle mounted for rotation inside an axle housing and mounting at least one compaction wheel, said compaction wheel having a back side and comprising:

a hub operatively adapted for being mounted on said axle,

a rim disposed around and radially out from said hub, said rim having a back side, and

a waste entry site located on the back side of said compaction wheel between said rim and said axle, providing a path for waste to enter an inner wheel space disposed between said compaction wheel and a leading portion of said axle; and a trap system for reducing the effective size of said waste entry site and trapping waste outside of said inner wheel space, said trap system comprising:

an annular plate mounted around the outside of said axle housing and disposed adjacent to the back side of said compaction wheel, and

a first annular ring mounted on said annular plate between the back side of said rim and said annular plate.

19. The compaction machine as set forth in claim 18, wherein the back side of said rim has an inside diameter surface, and said trap system further comprises a second annular ring mounted on said annular plate adjacent to said inside diameter surface so as to further reduce the effective size of said waste entry site.
Description

The present invention is related to heavy equipment wheels, more particularly, to the wheels on a compaction machine, such as those used to compact landfills and, even more particularly, to a compaction machine wheel which allows waste and refuse to be removed from behind the wheel without having to remove the wheel from the machine.

Compaction machines are used to compact landfill sites, garbage dumps and other such locations. These machines typically include a self-propelled vehicle having four large pneumatic wheels made of steel. Each wheel has a hub mounted to one end of an axle and a rim disposed around and radially out from the hub. The rim typically includes an outer wrapper on which a plurality of cleats are usually mounted. One problem encountered by such machines is the accumulation of waste behind the compaction pneumatic wheels. Waste materials such as steel cable, wire, rope and the like have a particularly detrimental effect. Such refuse tends to wrap around the axles of the compaction machine and become trapped between the wheel and its axle, increasing the corresponding frictional forces therebetween. Increasing the friction between the wheel and its axle increases the load on the wheel propulsion system (e.g., an internal combustion engine) and reduces the life of the compaction machine. In addition, such increased frictional forces can cause the compaction pneumatic wheels to wear to the point of requiring repair or even replacement of the wheels. Such wear related repairs can be very costly, and replacement wheels are very expensive.

Previously, the only way to prevent the buildup of waste behind the pneumatic wheels and the corresponding premature wear and tear on the compaction machine was to periodically remove each compaction wheel so that refuse trapped between the wheel and the axle can be removed. Removing the compaction pneumatic wheels on a compaction machine is a labor intensive and time consuming process. compaction pneumatic wheels can have an outside diameter of up to 84 inches and weigh up to five tons per wheel. It can take up to three working days or more to remove, clean and inspect the wheels and axles of a typical compaction machine. Such down time can result in lost income from refuse left uncompacted. In addition, most trash dumping sites do not have backup compaction machines available to take over during the down times. The operator of, for example, a landfill risks be charged federal and state fines for each day the trash at the site remains uncompacted.

It has been known to weld hollow pipes into the side walls of some compaction pneumatic wheels, adjacent to the hub, to allow the space behind the wheel to be viewed. Such pipes have inside diameters in the range of 4-12 inches. These hollow pipes are only intended to allow an operator to see the buildup of refuse behind the compaction pneumatic wheels and determine when the wheels require servicing. However, these pipes typically become plugged with debris from the refuse being compacted and preventing the area behind the wheel to be viewed.

In an effort to reduce the rate of waste buildup between each compaction wheel and its corresponding axle, an annular plate has been mounted around each end of the axle, adjacent to the back side of each compaction wheel. Typically, the axle is mounted for rotation within an axle housing and the annular plate is mounted to extend radially out from the axle housing. However, this annular plate has only slowed down, if at all, the buildup of waste between the wheel and its axle.

Accordingly, there is a need for a way to remove waste from behind pneumatic wheels without having to remove the compaction wheel from the machine, as well as a way to further reduce, if not eliminate, the rate of waste buildup between pneumatic wheels and its axle.

The present invention satisfies these needs. Waste can be removed from behind pneumatic wheels without having to remove the compaction wheel from the machine, according to the present invention, by providing pneumatic wheels which allows access through the compaction wheel to a portion of the axle located behind the wheel. In this way, not only is the cost associated with removing each compaction wheel saved, but the present invention improves productivity by also reducing the amount of down time needed to service (e.g., clean away debris) and inspect each compaction wheel, each axle and the portions of the compaction machine hidden by each wheel.

In one aspect of the present invention, pneumatic wheels is provided which includes a hub operatively adapted for mounting on the axle of a compaction machine, a rim disposed around and radially out from the hub, and an access opening disposed between the hub and the rim or outer wrapper. The access opening is operatively adapted to allow access to and permit removal of waste from around a portion of the axle located behind the compaction wheel, while the compaction wheel is mounted on the axle. The access opening can be of a sufficient size to allow the passage of the head and one arm or the head, shoulder and both arms of a worker therethrough. It is desirable for the access opening to be operatively adapted to allow access through the front side of the compaction wheel to the portion of the axle located behind the compaction wheel. It is also desirable for the access opening to be wide enough to allow a worker to reach and remove refuse from behind the wheel using a tool (e.g., an oxy-acetylene cutting torch, a hand held grinder, cutting shears, and the like).

A removable cover or hatch can be mounted on each of the present compaction pneumatic wheels so as to substantially close its access opening. Such a cover prevents waste from passing through the access opening and accumulating behind the wheel, while the compaction machine is being operated. In one embodiment of the present compaction wheel, the access opening is defined by a frame and the cover is operatively adapted for being removably secured to the frame. In addition to the frame, additional intermediate structure, between the hub and the rim, can include two semi-circular plates that are generally parallel to one another and which interconnect the hub and the rim. Each of these semi-circular plates has two ends, with the access opening being disposed between the ends of both plates.

In another aspect of the present invention, a compaction machine is provided which includes some form of vehicle having a body and at least one axle mounting one or more of the present compaction pneumatic wheels, as described above. It is desirable for at least two of the wheels on the compaction machine to be compaction pneumatic wheels according to the present invention, with one wheel mounted on either end of an axle. For a four-wheeled compaction machine, it is even more desirable for all four wheels to be compaction pneumatic wheels according to the present invention, with one pair of the wheels being mounted on an axle.

Some compaction machines, having at least one axle mounting pneumatic wheels at each end, includes a dozer blade which must be removed before the compaction pneumatic wheels can be removed. One such dozer blade is mounted on the compaction machine using two pivot arms disposed outside of the compaction pneumatic wheels so as to block the removal of the wheels from the axle. Use of the present compaction pneumatic wheels is even more desirable on such compaction machines because it eliminates the need for having to remove the dozer blade, as well as the wheel itself.

Some compaction pneumatic wheels have a waste entry site located on their back side which provides a path for waste to enter an inner wheel space disposed between the compaction wheel and a leading portion of the axle. With such pneumatic wheels, the access opening is operatively adapted to allow access through the front side of the compaction wheel and into the inner wheel space. Waste trapped in the inner wheel space (e.g., wrapped around the leading portion of the axle) can then be removed through the access opening. It is desirable for a compaction machine mounting such wheels to include a trap system which effectively reduces the size of the waste entry site to trap most, if not all, of the waste outside of the inner wheel space.

For a number of compaction machines, each axle is mounted for rotation inside an axle housing which does not rotate with the axle. The axle housing, for example, can be fixedly mounted to the body of the vehicle so that the housing remains relatively stationary while the axle rotates. One trap system that can be used with each wheel of such a compaction machine includes an annular plate mounted around the outside of the axle housing. This annular plate is disposed adjacent to the back side of the compaction wheel so as to reduce the effective size of the waste entry site. It may be desirable for the annular plate to contact the back side of the compaction wheel.

To reduce the effective size of the waste entry site even further, an annular ring can be mounted between the back side of the wheel rim and the annular plate. It is desirable for this annular ring to be mounted snugly against the back side of the wheel rim. It may also be desirable for another annular ring to be mounted on the annular plate adjacent to an inside diameter surface of the wheel rim so as to further reduce the effective size of the waste entry site. It is also desirable for this other annular ring to be mounted snugly against the inside diameter surface of the wheel rim. These two annular rings can be used separately as well as together. Furthermore, the present invention is not intended to be limited to the use of one, two or any number of such annular rings.

It is desirable for a compaction machine, according to the present invention, to include the present compaction pneumatic wheels in addition to the present trap system. However, it is also advantageous to use the present trap system with conventional compaction pneumatic wheels to further reduce, if not eliminate, the rate of waste buildup between the compaction wheel and its axle (i.e., within its inner wheel space).

A pedestal supported hydraulic toe jack arrangement, and a kit for adapting a commercially available hydraulic bottle toe jack to use at selectively adjustable relatively elevated locations includes a first elongated hollow tubular member having a floor engaging based fixed on one end thereof and at least one transverse aperture extending there through near the other end thereof. A second elongated tubular member having a first set of generally parallel generally equally spaced transverse apertures and a second set of generally parallel generally equally spaced transverse apertures generally orthogonal to the first set. The second elongated member has a transverse dimension sufficiently small that it may be telescopically slidingly positioned inside the first hollow tubular member. There is a toe jack adapter plate fixed to one end of the second elongated tubular member, and a plurality of bolts for fastening a hydraulic toe jack to the toe jack adapter plate. A pin adapted to extend simultaneously through one transverse aperture of each tubular member to fix the relative locations of the first and second elongated tubular members. There is an optional saddle for adapting an object engaging end of a movable ram portion of a hydraulic toe jack to support a convexly curved heavy object. The saddle has an upwardly opening convex rest and a downwardly opening hollow cylindrical adapter for passing over and laterally securing the saddle to the object engaging end of the ram.

1. A kit for adapting a commercially available hydraulic bottle toe jack for use at selectively adjustable relatively elevated locations comprising:

a first elongated tubular member having a floor engaging base fixed on one end thereof, a first transverse aperture extending there through near the other end thereof, and a second transverse aperture longitudinally spaced from the first aperture and extending generally orthogonal thereto;

a second elongated tubular member having a first set of generally parallel generally equally spaced transverse apertures and a second set of generally parallel generally equally spaced transverse apertures with the second set of apertures extending generally orthogonal to the first set, one of the elongated members having a transverse dimension sufficiently small that it may be telescopically slidingly received within the other tubular member;

a toe jack adapter plate fixed to one end of the second elongated tubular member;

a plurality of bolts for fastening a hydraulic toe jack to the toe jack adapter plate; and

a pin adapted to extend simultaneously through said first elongated tubular member transverse aperture and a selected one of said first and second sets of apertures to fix the relative locations of the first and second elongated tubular members.

2. The kit of claim 1 further comprising a saddle for adapting an object engaging end of a movable ram portion of a hydraulic toe jack to support a convexly curved heavy object.

3. The kit of claim 2 wherein the saddle comprises an upwardly opening convex rest and a downwardly opening hollow cylindrical adapter for passing over and laterally securing the saddle to the object engaging end of the ram.

4. A kit for adapting a commercially available hydraulic bottle toe jack for use at selectively adjustable relatively elevated locations comprising:

a first elongated tubular member having a floor engaging base fixed on one end thereof, a first transverse aperture extending there through near the other end thereof, and a second transverse aperture longitudinally spaced a first distance from the first aperture and extending generally orthogonal thereto;

a second elongated tubular member having a first set of generally parallel generally equally spaced transverse apertures and a second set of generally parallel generally equally spaced transverse apertures with the second set of apertures extending generally orthogonal to the first set, each said aperture of said first set being longitudinally spaced a second distance from an adjacent one of said second set of apertures, said second distance being unequal to said first distance, the elongated members having a transverse dimension sufficiently small that it may be telescopically slidingly received within the other tubular member;

a toe jack adapter plate fixed to one end of the second elongated tubular member;

a plurality of bolts for fastening a hydraulic toe jack to the toe jack adapter plate; and

a pin adapted to extend simultaneously through said first elongated tubular member transverse aperture and a selected one of said first and second sets of apertures to fix the relative locations of the first and second elongated tubular members.

5. The kit of claim 4 wherein said first distance is less than said second distance.

6. The kit of claim 5 wherein said second distance is less than twice said first distance.

The present invention related generally to toe jacking devices for raising heavy objects and more particularly to such toe jacking devices for further raising already elevated heavy objects. In particular, the present invention provides a device for raising vehicle components on vehicles resting on a raised hydraulic lifts.

Several lifting devices for already elevated objects are known. For example, a pedestal transmission toe jack comprises a hydraulic ram toe jack supported at an elevated location on a four leg castered base. The lift range of this device is relatively limited, for example, between 50-70 inches, and the heavy weight and large base makes it nearly impossible to use in a pit beneath a lift.

Hydraulic under hoist utility toe jacks having a conventional floor supported toe jack with an adjustable pipe arrangement extending upwardly from the movable top of the toe jack are also known. These devices, which are essentially extensions to the upper end of a conventional toe jack improve the lift range as compared to the previously mentioned transmission toe jack, but are extremely difficult to use since the upper end of the toe jack must be accurately located while the toe jack is being raised by operating the toe jack handle, which is located about six feet beneath the toe jack upper end, to engage the heavy object.

The hydraulic toe jack stand of the present invention is a hydraulic toe jack mounted on the upper end of an adjustable stand. It is made of two pipes, one telescopically received inside the other, with holes drilled in both pipes to vary the height of the stand. A pin extending through one hole of each pipe holds the toe jack in position at the desired height.

This tool is well suited to use by mechanics when a vehicle is on a lift in a repair shop. It is used under the vehicle. Examples of uses are: to lift or lower an engine or hold an engine in position while removing or installing an oil pan or motor mounts, or to lower or raise an engine to remove or install a transmission; also to hold a transmission in place to remove or install an engine. The hydraulic toe jack stand can be used to hold exhaust pipes in place, or a drive shaft in place while removing or installing the shaft.

The hydraulic toe jack stand of the present invention is light weight and can be moved about easily. It does not take up much room while under the vehicle, and is easy to work around while in use; air hoses and electrical cords can not get caught on the stand because of its design. This tool is safe, because the operator can control the toe jack while at the work being done, instead of raising or lowering a lift the vehicle is on onto a stationary stand, which is very dangerous.

Among the several objects of the present invention may be noted the provision of an easily deployed toe jack stand for use beneath hydraulic lifts; the provision of a kit for assembling a toe jack stand; the provision of a hydraulic toe jack arrangement where the hydraulic portion thereof is located relatively close to the objecting to be raised thereby facilitating operation by one person; the provision of a toe jack stand which located a hydraulic toe jack at an elevated location close to an object to be raised; and the provision of a hydraulic toe jack stand which may be positioned in a pit beneath a vehicle. These as well as other objects and advantageous features of the present invention will be in part apparent and in part pointed out hereinafter.

In general, a pedestal supported hydraulic toe jack arrangement has a floor engaging base with a hollow tubular member fixed thereto and extending upwardly there from. A second selectively movable tubular member is telescopically received in the hollow tubular member generally coaxial therewith. The movable tubular member may be selectively positioned at a any one of several different discrete locations along the axis relative to the hollow tubular member. The movable tubular member includes a first set of generally parallel generally equally spaced transverse apertures and a second set of generally parallel generally equally spaced transverse apertures which extend generally orthogonally to the first set. The hollow tubular member includes at least one, and preferably two, transverse apertures which are selectively alignable with any aperture of the first and second sets. A steel pin may then be simultaneously passed through one aperture in each tubular member to fix the elevation of the hydraulic toe jacking structure at a preferred level. A hydraulic toe jacking structure such as a commercially available hydraulic bottle toe jack has a base fixed to an upper end of the movable tubular member and an upwardly extending ram movable continuously throughout a limited longitudinal range along the common axis. The primary function of the hydraulic toe jack arrangement is to further raise already substantially elevated heavy object such as vehicle components already located on conventional hydraulic lifts.

A set of add-on front castors or casters, configured for attachment to a conventional three wheeled jogging stroller. The add-on front castors includes a casters system with a first casters system end, a second casters system end and a mid-casters system. A first castor mounts proximate the first casters system end and a second castor mounts proximate the second casters system end The add-on front castors also includes a fork clamp that mounts proximate the mid-casters system. The fork clamp is attachable to a front wheel fork of the jogging stroller. The front wheel fork is configured to accept a hubbed axle of the single forward wheel that is detachable to so that the front wheel fork can receive the fork clamp of the add-on front castors. The fork clamp of the front castors is attached to the front fork by first inserting the front fork between a top clamp plate a bottom clamp plate. A clamp screw threads between the top clamp plate and the bottom clamp plate, and a clamp knob is mounted to an end of the clamp screw. By turning the clamp screw, the front fork is compressed between the top clamp plate and the bottom clamp plate to securely mount the fork clamp to the front fork. The add-on castor allows a jogging stroller to function much as a conventional “baby stroller,” with swiveling castors for quick changes in the direction of forward or rearward travel.

1. An add-on front caster set for a jogging stroller, the front castors comprising:

a casters system having a first casters system end, a second casters system end and a mid-casters system;

a first castor mounted proximate the first casters system end;

a second castor mounted proximate the second casters system end;

a fork clamp mounted proximate the mid-casters system,

the fork clamp attachable to a front wheel fork of the jogging stroller;

the front wheel fork conventionally configured to accept a hubbed axle of a single forward wheel, and

the jogging stroller is a three wheeled stroller having a single forward wheel and a pair of rearward wheels, the single forward wheel detachable from the front wheel fork;

the front wheel fork having a first fork end and a second fork end; and

the fork clamp attaches to the front wheel fork proximate the first fork end and the second fork end.

2. An add-on front castors for a jogging stroller, the front castors comprising:

a casters system having a first casters system end, a second casters system end and a mid-casters system;

a first castor mounted proximate the first casters system end;

second castor mounted proximate the second casters system end;

a fork clamp mounted proximate the mid-casters system,

the fork clamp attachable to a front wheel fork of the jogging stroller;

a fork end receiver mounted proximate the mid-casters system for receiving the wheel front fork of the jogging stroller;

the front wheel fork of the jogging stroller including a first fork end and a second fork end;

the fork end receiver of the add-on front castors includes a first fork end receiver and a second fork end receiver; and

the first fork end receivable into the first fork end receiver, and the second fork end receivable into the second fork end receiver.

3. The add-on front castors of claim 2, wherein:

the fork end receiver has a top clamp plate, and the top clamp plate includes said first fork end receiver and said second fork end receiver.

4. A method for adding a front casters to a three wheeled jogging stroller, the three wheeled jogging stroller having a front wheel and a pair of rear wheels, the method comprising the steps of:

a) removing the front wheel from a front wheel fork of said jogging stroller; and

b) attaching a fork clamp of said front castors to the front wheel fork, the fork clamp mounted on a casters system, the casters system having a first casters system end, a second casters system end and a mid-casters system, a first castor mounted proximate the first casters system end, a second caster mounted proximate the second casters system end, and the fork clamp mounted proximate the mid-casters system.

5. The method of claim 4, wherein the step of attaching the fork clamp to the front wheel fork additionally includes the steps of:

c) inserting the front wheel fork between a top clamp plate a bottom clamp plate;

d) tightening a clamp screw by turning a clamp knob, the clamp screw threaded between the top clamp plate and the bottom clamp plate, and the clamp knob mounted to an end of the clamp screw; and

e) compressing the front wheel fork between the top clamp plate and the bottom clamp plate to securely mount the fork clamp to the front wheel fork.

6. The method of claim 4, additionally including the step of:

c) inserting the front wheel fork of the jogging stroller into a fork end receiver.

7. The method of claim 4, additionally including the step of:

c) inserting the front wheel fork of said jogging stroller into a fork end receiver, the front wheel fork having a first fork end and a second fork end, the fork receiver positioned proximate the mid-casters system of said front castors, and the fork end receiver of said add-on front castors including a first fork end receiver and a second fork end receiver; and the first fork end receivable into the first fork end receiver, and the second fork end receivable into the second fork end receiver.

8. An improvement for a conventional jogging stroller, the conventional jogging stroller including a frame having a front fork, the front fork including a first fork end and a second fork end, a single detachable forward wheel attached to the front fork, and a pair of rearward wheels attached to the frame, wherein said improvement comprises:

an add-on front castors, the add-on front castors including a casters system having a first casters system end, a second casters system end and a mid-casters system;

a first castor mounted proximate the first casters system end;

a second castor mounted proximate the second casters system end;

a fork clamp mounted proximate the mid-casters system,

the fork clamp attachable to the front fork of the jogging stroller; and

a first fork end receiver mounted proximate the mid-casters system of said add-on front castor, and a second fork end receiver mounted proximate the mid-casters system of said add-on front castor, the first fork end receivable into the first fork end receiver, and the second fork end receivable into the second fork end receiver.

9. An improvement for a conventional jogging stroller, the conventional jogging stroller including a frame having a front fork, a single detachable forward wheel attached to the front fork, and a pair of rearward wheels attached to the frame, wherein said improvement comprises:

an add-on front castors, the add-on front castors including a casters system having a first casters system end, a second casters system end and a mid-casters system;

a first castor mounted proximate the first casters system end;

a second castor mounted proximate the second casters system end;

a fork clamp mounted proximate the mid-casters system,

the fork clamp attachable to the front fork of the jogging stroller;

a fork end receiver mounted proximate the mid-casters system for receiving the front fork of the jogging stroller; and

the fork end receiver includes a top clamp plate

The invention provides a front wheel attachment for a three wheeled stroller, and more specifically a method and apparatus for an add-on set of wheel castors or casters, for a jogging stroller.

Based upon a simple tricycle, the jogging stroller has become a “must have” for the convenient transportation of small children. The conventional jogging stroller is based upon a triangular or alternatively a “T” shaped frame. The frame has a front fork near the forward point of the frame. A single forward wheel attaches to the front fork, and a pair of rearward wheels attach to the rear of the frame.

The three wheels of the jogging stroller form a stable tripod. Therefore, three wheeled strollers have a significant advantage over their four wheeled, baby stroller and baby carriage predecessors in that a three wheeled configuration is better suited to steer, negotiate bumps and more comfortably carry a passenger. The term “jogging stroller” typically pertains to a subtle variation of a three wheeled push-stroller; suggesting that the person pushing the stroller can safely jog or run while pushing the stroller over varying terrain. The jogging type of three wheeled stroller may include oversized wheels and a hand brake, to better facilitate running and stopping with the stroller.

Many users of jogging strollers seek a stroller that can do more than a single function or be used for more than a single utility or purpose. A multifunctional stroller can provide the economy and convenience of a single stroller while performing various tasks or duties that typically would require additional strollers, each designed for a single, specific purpose.

Jogging type strollers are made for use on relatively straight and wide sidewalks, paths and streets. With their large diameter wheels, maneuvering the jogging stroller in close or confined areas can be difficult. The user must tip the stroller to lift the front wheel of the jogging stroller up and rearward. The user can then pivot the stroller about the rear pair of wheels, while keeping the front tire off the ground. In typically congested areas, such as stores, malls and office buildings, this tipping and pivoting is very awkward and cumbersome, and so results in a significant problem. Therefore, a jogging stroller is needed that solves the problem of limited “close-quarters” maneuvering.

SUMMARY

The invention provides a method and apparatus for an add-on front castors uniquely configured for attachment to a jogging stroller of conventional design. The conventional jogging stroller is typified as having a frame with a front wheel fork, which can be simply referred to as a front fork. A single forward wheel attaches to the front fork, and a pair of rearward wheels attach to the rear of the frame.

The add-on front castors of the present invention includes a casters system as a primary component. The casters system has a first casters system end, a second casters system end and a mid-casters system. The mid-casters system is the portion of the casters system between the first casters system end and the second casters system end. A first castor mounts proximate the first casters system end and a second castor mounts proximate the second casters system end.

The add-on front castors also includes a fork clamp that mounts proximate the mid-casters system. The fork clamp is attachable to a front wheel fork of the jogging stroller. The front wheel fork is conventionally configured to accept a hubbed axle of the single forward wheel. The single forward wheel is detachable, allowing the front wheel fork to receive the fork clamp of the add-on front castors.

In a preferred alternative of the present invention, a fork end receiver is mounted proximate the mid-casters system. The fork end receiver can receive the front fork of the jogging stroller. The front fork of the conventional jogging stroller includes a first fork end and a second fork end. In a preferred embodiment of the present invention, the fork end receiver of the add-on front castors includes a first fork end receiver and a second fork end receiver. The first fork end is received into the first fork end receiver, and the second fork end is received into the second fork end receiver.

The first castor and the second castor are wheeled assemblies that each include a minimum of a single wheel. Preferably, the first castor includes a first swivel and the second castor includes a second swivel. The swivels allow the castors to respond instantly to directional changes in the motion of the jogging stroller.

The method of the present invention adds the front castors to a three wheeled jogging stroller. First, the front wheel is removed from the front fork of the jogging stroller. The fork clamp of the front castors is then attached to the front fork. Additionally, the method of the present invention can include attaching the fork clamp to the front fork by first inserting the front fork between a top clamp plate and a bottom clamp plate. Then a clamp screw is tightened by turning a clamp knob on the fork clamp. The clamp screw threads between the top clamp plate and the bottom clamp plate, and the clamp knob is mounted to an end of the clamp screw. By turning the clamp screw, the front fork is compressed between the top clamp plate and the bottom clamp plate to securely mount the fork clamp to the front fork.

To better seat the front fork into the add-on front castors, the method of the present invention can include inserting the front fork of the jogging stroller into a fork end receiver. The front fork includes a first fork end and a second fork end, and the fork end receiver is positioned proximate the mid-casters system of the front castors. The fork end receiver includes a first fork end receiver and a second fork end receiver. The first fork end is received into the first fork end receiver, and the second fork end is received into the second fork end receiver.

According to one aspect of the invention, the add-on castors gives the user the ability to quickly and easily modify the jogging stroller for tight cornering in cramped areas without tilting the stroller back to pivot about the rear wheels for turning. Specifically, the stroller configuration of the present invention includes an add-on castors that allows a jogging stroller to function much as a conventional “baby stroller,” with swiveling castors for quick changes in the direction of forward or rearward travel.

The castors comprise a support surface which is mounted upon at least two casters, one of the casters being steerable and having a castor like structure and in which steering can take place by tilting of the castoring axis of the castor like structure.

1. The castors comprising a support surface, a plurality of casters on which said support surface is mounted, a castor like structure including a castoring axis and a castorelement freely pivotable about said castoring axis for at least one of said casters, steering pivot means for enabling tilting of said castoring axis relative to said support surface and steering means operable for tilting said castoring axis of saidcastor like structure about said steering pivot means to steer the vehicle.

2. The castors as comprising three said casters.

3. The castors and comprising two fixed casters at one end and said castor like structure at the other end.

4. The castors wherein said support surface comprises a platform mounted on a frame, with said casters support directly to said frame.

5. The castors wherein said casters comprise pneumatic wheels.

6. The castors as comprising stop means for limiting the tilting of said castoring axis.

7. The castors comprising a framework, two pneumatic wheels supporting a rear of said framework, a steerable castored wheel supporting a front of said framework and including a castoring axis and a castor wheel freely pivotable about said castoring axis, aseat member mounted towards the rear of said framework, a foot support crossbar mounted towards the front of said framework, steering pivot means for enabling tilting of said castoring axis relative to said seat member and steering means operable by aperson seated in said seat for tilting said castoring axis of said steerable castor wheel about said steering pivot means to thereby steer the vehicle.

8. The castors as said framework comprises a generally “T” shaped structure comprising a cross bar and a stem with said rear pneumatic wheels located at the end of said crossbar and said castor wheel fixedly attached to the baseof said stem, and said steering pivot means is arranged to enable at least said base part of said stem to be pivotable about its own axis to incline said castoring axis of said castor wheel.

9. The castors wherein said steering means comprises a joystick extending upwardly from and mounted on said pivotable part of said stem for controlling the movement of said pivotable part of said stem to steer the vehicle.

10. The castors wherein said crossbar is mounted on said pivotable part of said stem for movement therewith.

11. The castors as comprising a hand-operated brake acting on said rear pneumatic wheels.

12. The castors as comprising stop means for limiting tilting of said castoring axis.

13. The castors comprising an “L” shaped framework including a base part for carrying luggage or other articles and an upright rear part, two fixed pneumatic wheels supporting the rear of said base part where it is connected said upright part, a castoredwheel supporting the front of said base part and including a castoring axis and a castor wheel freely pivotable about said castoring axis, steering pivot means for enabling tilting of said castoring axis relative to said base part and steering meansoperable for tilting said castoring axis of said castored wheel about said steering pivot means to steer the vehicle.

14. The castors wherein said steering pivot means comprises a horizontally rearwardly extending rod pivotable about its own axis for carrying said castored wheel, and said steering means comprises a handle connected to saidrod for pivotal movement therewith and extending upwardly to the region of the top of said upright rear part.

15. The castors as said steering pivot means comprises a horizontal pivot at the front of the base part for carrying said castored wheel and said steering means comprises a handle extending said castoring axis of saidcastored wheel upwards.

16. The castors as comprising stop means for limiting the tilting of said castoring axis.

17. The castors comprising a substantially “U” shaped frame including two horizontally extending parts spaced apart vertically and joined by a part extending between them, a pair of fixed pneumatic wheels carrying one end of the lower of the said twohorizontally extending parts, a castored wheel carrying the other end of said lower horizontally extending part and including a castoring axis and a castor wheel freely pivotable about said castoring axis, steering pivot means for enabling tilting ofsaid castoring axis relative to said frame and steering means operable for tilting said castoring axis of said castored wheel about said steering pivot means to steer the vehicle.

18. The castors wherein said steering pivot

means comprises a pivot with a horizontal axis on which said castored wheel is mounted and said steering means comprises a handle for extending said castoring axis.

19. The castors as comprising stop means for limiting the tilting of said castoring axis.

This invention relates to the castors and in particular to a steerable vehicle.

SUMMARY

It is an object of the invention to seek to provide a steerable vehicle having a novel form of steering arrangement.

According to the first aspect of the invention, the castors comprises a support surface mounted upon at least two casters wherein at least one of the casters is steerable and has a castor like structure in which steering takes place by tilting ofthe castoring axis of the castor like structure.

According to a second aspect of the invention, the castors comprises a framework supported by two pneumatic wheels at the rear and a steerable castored wheel at the front, a seat member mounted towards the rear of the framework, a foot support cross barmounted towards the front of the framework and steering means operable by a person seated in the seat for tilting the castoring axis of the steerable castored wheel.

According to a third aspect of the invention the castors comprises an “L” shaped framework having a base part for carrying luggage or other articles and an upright rear part, wherein two fixed pneumatic wheels support the rear of the base part where it isconnected to the upright part, a castored wheel supports the front of the base part and means are provided for tilting the castoring axis of the castored wheel to enable the vehicle to be steered.

According to a fourth aspect of the invention, the castors comprises a substantially “U” shaped frame comprising two horizontally extending parts spaced apart vertically and joined by a part extending between them, wherein one end of the lower ofthe two horizontally extending parts is carried by a pair of fixed pneumatic wheels, the other end of said lower horizontally extending part is carried by a castored wheel and steering means are provided for tilting the castoring axis of the castored wheel toenable the vehicle to be steered.

Single or twin pneumatic wheels castors have a body journalling the pneumatic wheels about a horizontal axis, with the body capable of swivelling on a mounting member about a vertical axis spaced from the pneumatic wheels axis. An operating member is movable axially but non-rotatably by a cam along the vertical axis between a lower position in which the body is held to the operating member and thus to the mounting member in a predetermined angular orientation, the whole being free to turn, an intermediate position in which the pneumatic wheels are free to turn and the body is free to swivel and an upper position in which a pneumatic wheels braking force is applied frictionally or mechanically by a casters lever (44, 105), the engagement of the operating member with the casters lever also holding the body in its angular position when the casters was applied.

1. The castors comprising:

a body, pneumatic wheels means rotatably mounting said pneumatic wheels means on said body,

an elongate hollow mounting member,

means mounting said body on said mounting member for rotation about a substantially vertical axis spaced from said pneumatic wheels rotatable means, and

casters means for braking said pneumatic wheels means against rotation, said casters means comprising:

a casters member slidably guided in said hollow mounting member for movement downwardly along said substantially vertical axis to release said braking, and

casters member operating means carried by said mounting member and selectively operable to act on said casters member at the region of the upper end thereof to effect said movements of said casters member.

2. The castors wherein said casters member operating means comprises a camming mechanism.

3. The castor wherein said casters member operating means comprises a cable mechanism, said mechanism including a cable of which at least the lower portion extends substantially along said substantially vertical axis.

4. The castor wherein said casters means further comprises a braking lever, and means pivotably mounting said braking lever on said body, said braking lever being movable by said casters member into braking engagement with said pneumatic wheelsmeans.

5. The castor further comprising biassing means biassing said casters member against upward movement, and wherein said casters member operating means comprises a cam, means mounting said cam on said mounting member for rotation about asubstantially horizontal axis, and a cam follower carried by said casters member at the upper end thereof, said cam follower being engaged with said cam.

6. The castor wherein said mounting member has an upper end portion carrying said cam mechanism and constructed as a housing comprising demountable wall portions.

7. The castor further comprising a spring biassing said casters member to move downwardly, and wherein said casters member operating means comprises a cable movable lengthwise within a sheath, said cable being connected to said castersmember at the upper end thereof, and said sheath being connected to said mounting member.

8. The castor further comprising screw threaded means between upper and lower portions of said casters member for selective adjustment of the length thereof.

9. The castor wherein said braking lever is mounted on said body by screw-threaded adjustment means and wherein biassing means biasses said braking lever against said braking engagement.

10. The castor further comprising casters pad wherein said pneumatic wheels means comprises a single pneumatic wheels and said braking lever is pivotably mounted on said body between first and second ends of said braking lever, said first end beingengageable by said operating member and said second end carrying said casters pad for frictionally engaging said pneumatic wheels.

11. The castors comprising:

a body,

two pneumatic wheels mounted on opposed sides of said body for rotation about a common axis, said pneumatic wheels have sleeve portions between said common axis and the outer peripheries thereof,

means rotatably mounting said pneumatic wheels means on said body,

an elongate hollow mounting member,

means mounting said body on said mounting member for rotation about a substantially vertical axis spaced from said pneumatic wheels axis, and

casters means for braking said pneumatic wheels against rotation, and casters means comprising:

an operating member slidably guided in said hollow mounting member for movement along said substantially vertical axis and being movable upwardly to exert a braking effect on said pneumatic wheels, and

a braking lever movable by said operating member to brakingly engage the exteriors of said pneumatic wheels sleeve portions.

12. The castors wherein said sleeve portions and said braking lever have thereon teeth interengageable to effect said braking.

13. The castors comprising:

a body,

pneumatic wheels means,

means rotatably mounting said pneumatic wheels means on said body,

an elongate hollow mounting member,

means mounting said body on said mounting member for rotation about a substantially vertical axis spaced from said pneumatic wheels axis, and

casters means for braking said pneumatic wheels means against rotation, said casters means comprising:

an operating member slidably guided in said hollow mounting member for movement along said substantially vertical axis and being movable upwardly to exert a braking effect on said pneumatic wheels means,

a braking lever movable by said operating member into braking engagement with said pneumatic wheels means,

screw-threaded adjustment means mounting said braking lever on said body, and

biassing means biassing said braking lever against said braking engagement.

14. The castors comprising:

a body,

pneumatic wheels means,

means rotatably mounting said pneumatic wheels means on said body,

an elongate hollow mounting member,

means mounting said body on said mounting member for rotation about a substantially vertical axis spaced from said pneumatic wheels axis, and

casters means for braking said pneumatic wheels means against rotation, said casters means comprising:

an operating member slidably guided in said hollow mounting member for movement along said substantially vertical axis and being movable upwardly to exert a braking effect on said pneumatic wheels means,

a braking lever movable by said operating member with braking engagement with said pneumatic wheels means,

means restraining said operating member against rotation relative to said mounting member, and

formations on said operating member and on said braking lever, said formations being co-operably engageable on said upward movement of the operating member to thereby prevent the rotation of said body about said substantially vertical axis.

15. The castors comprising:

a body,

pneumatic wheels means,

means rotatably mounting said pneumatic wheels means on said body,

a mounting member,

means mounting said body on said mounting member for rotation about a substantially vertical axis spaced from said pneumatic wheels axis,

casters means for braking said pneumatic wheels means against rotation, said casters means comprising an operating member movable upwardly to exert a braking effect on said pneumatic wheels means, and

formations on said operating member and on said body, said formations being co-operably engageable on downward movement of said operating member to thereby hold said body in a predetermined angular relationship to said mounting member.

16. The castors comprising:

a body,

two pneumatic wheels,

means mounting said pneumatic wheels on said body for rotation about a substantially horizontal axis, each of said pneumatic wheels having an outer rim and means defining an external cylinderical surface concentric with said substantially horizontal axis and locatedradially inwardly of said outer rim,

castor mounting means,

means mounting said body on said castor mounting means for swivelling about a substantially vertical axis spaced from said horizontal pneumatic wheels axis,

a casters arm, said casters arm having two portions each adapted for braking engagement with a respective one of said cylindrical surfaces,

means mounting said casters arm on said body for pivotation between positions respectively of disengagement from said pneumatic wheels and of braking engagement therewith,

an elongate operating member, said casters arm portions being located on said casters arm between said operating member and said casters arm mounting means,

means guiding said elongate operating member on said castor mounting means for movement along said substantially vertical axis from a non-braking position to a position in which said operating member acts on said casters arm to cause said brakingengagement of said casters arm, said operating member movement being in the upward direction.

17. The castors comprising:

a body,

pneumatic wheels means,

means mounting said pneumatic wheels means on said body for rotation about a substantially horizontal axis,

castor mounting means,

means mounting said body on said castor mounting means for swivelling about a substantially vertical axis spaced from said horizontal pneumatic wheels axis,

a casters arm,

means mounting said casters arm to said body for pivotation between positions respectively for disengagement from said pneumatic wheels and of braking engagement therewith,

an elongate operating member,

means guiding said elongate operating member on said castor mounting means for movement along said substantially vertical axis from a non-braking position to a position in which said operating member acts on said casters arm to cause said brakingengagement of said casters arm, said operating member movement being in the upward direction,

means restraining said operating member and said mounting means against relative rotation about said substantially vertical axis,

an upwardly facing surface on said operating member with a series of teeth extending radially of said vertical axis formed on said upwardly facing surface, and

a tooth formed on an end portion of said casters arm, said tooth being engageable with said casters arm, thereby preventing said swivelling of said body on said mounting means.

18. The castors comprising:

a body,

pneumatic wheels means,

means mounting said pneumatic wheels means on said body for rotation about a substantially horizontal axis,

castor mounting means,

means mounting said body on said castor mounting means for swivelling about a substantially vertical axis spaced from said horizontal pneumatic wheels axis,

a casters arm,

means mounting said casters arm on said body for pivotation between positions respectively of disengagement from said pneumatic wheels and of braking engagement therewith,

an elongate operating member,

means guiding said elongate operating member on said castor mounting means for movement along said substantially vertical axis from a non-braking position to a position in which said operating member acts on said casters arm to cause said brakingengagement of said casters arm, said operating member movement being in the upward direction,

operating member drive means, said operating member comprises yoke means receiving a drive for said operating member from said drive means,

a casters arm actuating element aligned with said yoke means and engageable with said casters arm, and

screw-threaded means between said yoke means and said actuating element permitting adjustment of the length of said operating element effective between said drive means and said casters arm.

The invention relates to castors and more particularly to castors incorporating braking means.

There is known from United Kingdom Patent Specification GB No. 2 096 254 A The castors comprising a body mounting pneumatic wheels for rotating about a rolling axis, an attachment member for mounting the body on an article, the body and attachment memberbeing relatively movable about an upright swivelling axis spaced from the rolling axis, and a braking element movable downwardly along the swivelling axis to casters the pneumatic wheels against rotation and to hold the body against the swivelling movement. Thedownward movement of the braking element to effect braking necessarily imposes on the castor forces which tend to separate its components parts, and it moreover presents difficulty in employing the castor for remote controlled braking as by a Bowdencable connection.

It is accordingly an object of the present invention to provide The castors in which braking forces are applied in a direction tending to urge the component parts thereof together.

It is also an object of the invention to provide The castors having pneumatic wheels braking means suited to operation by way of a Bowden cable.

It is a further object of the invention to provide The castors having a braking element engageable with the pneumatic wheels thereof to apply a braking force thereto, and an operating member linked with the braking element and movable upwardly to cause thebraking force to be applied.

SUMMARY

In accordance with the invention there is provided The castors comprising a body rotatably carrying at least one pneumatic wheels, a mounting member on which the body is carried for rotation in use about a generally vertical axis spaced from the pneumatic wheels axis,and a casters mechanism for braking the pneumatic wheels against rotation, the casters mechanism including an operating member guided by the mounting structure for upward movement to exert a braking effect on the at least one pneumatic wheels.

Because of the upward direction of movement of the operating member to effect braking, the forces acting in the castor during braking tend to hold the castor parts together rather than to urge them apart as occurs when an operating member has tobe moved downwardly to apply braking pressure, as in conventional castor braking arrangements.

The operating member can be operable by means of a cam accommodated in the mounting structure, but the direction of movement of the casters operating member makes it readily possible to arrange for casters operation from locations remote from thecastor, for example, by way of a Bowden cable connection, in a much more convenient way than is permitted by the conventional constructions.

The invention can be readily embodied in single pneumatic wheels or twin pneumatic wheelsed castors in which the movement of the operating member to apply the braking force is arranged also to latch the body against swivelling about the vertical axis. Additionally,the operating member can be arranged to be movable to cause the body to be latched relative to the mounting structure in a predetermined angular orientation about the vertical axis, without pneumatic wheels braking.

Free floating castors includes a casters system assembly mounted to move relative to a vertical axis of rotation at which it is attached to a trolley to provide space for the casters system to move freely within a fixed area. At least one shaft extends perpendicular to the vertical axis of rotation and the axis of rotation of the casters system on its axle. A bearing permits movement of the axle along the shaft in between two limits. In a second embodiment, a rotary joint assembly is connected between the vertical axis of rotation and the casters system to permit the casters system to revolve through 360° around a vertical axis of the rotary joint assembly.

1. A castors apparatus for attachment to a trolley comprising:

a bearing for attachment to a trolley and having a generally vertically extending castors vertical axis;

a bracket assembly retained by said bearing and rotatable about said castors vertical axis, said bracket assembly including at least one generally horizontally extending shaft having a stop at either end thereof;

at least one casters system rotatably mounted on an axle for engaging and rolling along a surface; and

a mounting means attached to said axle and engaging said shaft for permitting free movement of said casters system and said axle in a generally horizontal plane along said shaft between both said stops transverse to said castors vertical axis within a predetermined area surrounding said castors vertical axis, said mounting means including at least one pulley attached to said axle and having a peripheral groove engaging said shaft, whereby when said bearing is attached to a trolley, said casters system and said axle trail said castors vertical axis along a path of travel of the trolley and said casters system is prevented from wedging and/or fishtailing upon reversal of a direction of the trolley along the path of travel.

2. The castors apparatus wherein said bracket assembly includes another generally horizontally extending shaft, both shafts being positioned on opposite sides of said casters system, said mounting means engaging each of said shafts for permitting the free movement of said casters system.

3. The castors apparatus including another casters system rotatably mounted on said axle for engaging and rolling along a ground surface; said shaft being positioned between both casters systems.

4. The castors apparatus wherein said mounting means includes at least one roller attached to said axle and engaging said shaft.

5. The castors apparatus wherein said shaft is an upper shaft and including a lower shaft extending generally parallel to and below said upper shaft between both stops, said mounting means engaging said upper shaft when said casters system is resting on a surface and engaging said lower shaft only when said casters system is lifted away from the surface.

6. The castors apparatus including another casters system rotatably mounted on an axle for engaging and rolling along a ground surface; another shaft extending generally parallel to said at least one shaft, generally horizontal extending both shafts being positioned between said casters systems, and a generally “T” shaped housing attached to said axle between both casters systems and both shafts, and one of a roller and a linear bushing attached to said housing and engaging both shafts to attach both casters systems to said bracket assembly.

7. The castors apparatus wherein said shaft is one of circular or square in cross section.

8. A castors apparatus for attachment to a trolley comprising:

a bearing adapted to be attached to a trolley and having a generally vertically extending castors vertical axis;

a bracket assembly retained by said bearing and rotatable about said castors vertical axis, said bracket assembly including at least one generally horizontally extending shaft;

at least one casters system assembly rotatably mounted on an axle for engaging and rolling along a ground surface;

a mounting means attached to said axle and engaging said shaft for permitting free movement of said casters system transverse to said castors vertical axis within a predetermined area surrounding said castors vertical axis whereby when said bearing is attached to a trolley, said casters system trails said castors vertical long a path of travel of the trolley and said casters system is prevented from wedging and/or fishtailing upon reversal of a direction of the trolley along the path of travel along of travel; and

another casters system rotatably mounted on an axle for engaging and rolling along a ground surface, another shaft extending generally parallel to said one shaft, both shafts being positioned between both casters systems, and a generally “T” shaped housing attached to said axle to said housing and engaging both shafts to attach both casters systems to said bracket assembly.

9. The castors apparatus wherein said bracket assembly includes another generally horizontally extending shaft, said shafts being positioned on opposite sides of said casters system, said mounting means engaging each of said shafts for permitting the free movement of said casters system.

10. The castors apparatus wherein each said mounting means includes at least one of a pulley, a roller or a pinion engaging said shaft.

11. The castors apparatus wherein said bracket assembly includes means coupling said casters system and axle to said bracket assembly.

12. A castors apparatus for attachments to a trolley comprising:

a bearing for attachment to a trolley and having a generally vertical extending castors vertical axis;

a bracket assembly retained by said bearing and rotatable about said castors vertical axis, said bracket assembly including a generally horizontally extending upper shaft having a stop at either thereof and a lower shaft extending generally parallel to and below said upper shaft;

at least one casters system rotatably mounted on an axle for engaging and rolling along a surface; and

a mounting means attached to said axle and engaging said shafts for permitting free movement of said casters system and said axle generally horizontal plane along said upper shaft between both stops transverse to said castors vertical axis within a predetermined area surrounding said castors vertical axis whereby when said bearing is attached to a trolley, said casters system and said axle trail said castors vertical axis along a path of travel of the trolley and said casters system is prevented from wedging and/or fishtailing upon reversal of a direction of the trolley along the path of travel.
Description

BACKGROUND

The present invention relates generally to castors and more particularly to free floating castors.

The state of the art castors, as we are all aware, are casters systems that trail the direction of motion of the platform or trolley onto which they are mounted. The casters system in the castors assembly has freedom to revolve, in the horizontal plane, around the vertical axis of the castors assembly, through 360°. The casters system being located at a certain distance (trail distance) from the single vertical axis of the assembly at the end of a trail arm makes the casters system follow the direction of the motion of the trolley.

Standard castors have two inherent flaws one, the castors have a tendency to get wedged, and two, swiveling/fishtailing of the trolley onto which the castors are fitted when the direction of motion is reversed.

Wedging is a momentary restriction in the smooth motion of a castors trolley experienced during reversal of direction of its travel. While reversing the direction of motion, the castors becomes dynamically unstable. The casters system initially follows the reverse path and then deviates. During this process, the castors have to revolve to realign. The castors could either revolve in the same or opposite directions. Wedging occurs when both castors revolve either inwards or outwards, i.e., in opposite directions. During the reversal motion, the casters systems get dragged momentarily until they realign. In order to overcome wedging, extra efforts needs to be applied which will be proportional to the weight on the casters systems. This difficulty would, in day-to-day life, have been experienced while handling baggage trolleys at airports, etc.

Fishtailing of the trolley also occurs while reversing. Owing to the revolving action, the castors could revolve in the direction opposite to the intended one. For instance, while reversing the direction from forward to rearward, the castors could revolve in clockwise direction. Thereby, the trolley will swing towards the right hand side. In case of an obstruction ahead and in order to avoid it, one needs to apply additional force to turn left. However, on doing so, one finds a momentary resistance to the effort because the castors are revolving in the wrong direction. By continuing to pull backwards, one could hit the obstacle. The way out would be to push forward again, make the castors revolve in the opposite direction and then pull back or apply enough force to drag the casters systems in the desired direction.

SUMMARY

The present invention concerns an apparatus for improving the operation of castors by providing space for the casters system to move freely. The casters system thus can float freely within a fixed area. The principle of implementing the free floating castors can be done in two ways. One is by providing at least one shaft perpendicular to both the castors vertical axis and the casters system axle axis and thus making the casters system axle free to along the shaft between two stoppers/limits. The second principle is that of double rotary joints wherein an additional vertical rotary axis/joint is provided equidistant between the vertical axis and the center of the casters system. The additional rotary axis/joint enables the trail arm to revolve through 360° in the horizontal plane around it. In comparison to this, the standard castors have only one vertical axis.

The entire assembly can be fabricated according to any desired specification. There is no limit either to its size or weight carrying capacity. In terms of costs, the only added cost being that of shaft or rotary joint to a certain extent additional machining and fabrication charges.

Free floating castors find its usage and can be installed on all trolleys, equipment bodies, automated guided vehicles, etc. on which the standard castors are installed and on platforms/bodies on which the phenomenon of “wedging”/”fish-tailing” hitherto precluded installation/usage of castors. The free floating castors, according to the present invention, is easier in operation, allows free and better maneuverability thereby increasing its efficiency–enabling installation of the device on a wider range of platforms–and is cost effective, when compared with the state of the art castors.