Trailer sub-frame assembly
A sub-frame assembly for use with a vehicle having wheels such as a trailer is provided. The sub-frame assembly comprises two or more frame members, one or more cross members, and two or more stub torsion axle assemblies. Each of the stub torsion axle assemblies have a torsion arm, a spindle extending from the torsion arm for mounting one of the wheels, and a distal end extending from the stub torsion axle assembly for mounting to the frame assembly. The frame assembly may further comprise one or more shim plates for reception between the cross member and the distal end of the stub torsion axle assembly for allowing adjustment of the toe angle of the wheel assembly. In addition, the stub torsion axle assembly may be rotatably mounted to the cross member whereby the camber angle of the wheel assembly may be adjusted.
This application claims the benefit of U.S. provisional (Number not yet assigned) filed on May 30, 2003, Express Label No. EL084750519US, and entitled TRAILER SUB-ASSEMBLY (attorney docket number 21488/04134), which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTIONThe invention relates generally to towable trailers, and more particularly to the assembly and manufacture of a sub-frame assembly for a trailer.
BACKGROUND OF THE INVENTIONPrior art trailers such as those used in hauling portable equipment, livestock or recreational travel trailers typically use tandem axles. The axles are typically supplied to the trailer manufacturer from the axle manufacturer. The trailer manufacturer must then install and align both axles on the trailer as well as wire or plumb the brakes of each axle assembly to the trailer. Proper alignment of the axles on the trailer can be tedious and time-consuming. Further, once the axle has been installed it is very difficult to realign, and it is often necessary to replace the entire axle if one of the wheel ends has become misaligned or damaged.
Thus an improved axle sub-frame assembly for a trailer is desired which provides for independent alignment and realignment of each wheel, as well as easy installation of the axle sub-frame assembly by the trailer manufacturer.
DESCRIPTION OF THE DRAWINGS
A first embodiment of a sub-frame assembly 10 of the present invention is shown in
One advantage of the subframe 30 of the invention is that the cross members 32 and the frame members 34 substantially support the axle loads in an efficient manner so that the trailer frame members may be reduced in cross-sectional size. Another advantage of the subframe 30 is that the subframe may be prewired/preplumbed so that the electrical/hydraulic brake lines 31 of each wheel assembly 50 are joined together in a central hookup location 35 such as shown in
A torsion axle stub assembly 40 is secured to the sub-assembly 10 at each of the desired wheel locations. Utilizing stub axles allows for independent adjustment of the camber and toe angles of each wheel assembly as described in more detail, below. A first end 42 of an axle stub assembly 40 is inserted through aligned hole 36 of frame member 34 and hole 37 of mounting bracket 33. Preferably, the mounting bracket 33 is welded to the stub axle prior to assembly to the sub-frame. The first end 42 of the axle subassembly is mounted to cross member 32 via cam bracket 38 as shown in
Another aspect of the invention is the ability to independently adjust the toe angle of each wheel assembly. As best shown in
Another aspect of the invention is the ability to independently adjust each camber angle β for a given wheel assembly. Further, for each wheel assembly, the camber angle β can be adjusted independently of the toe angle α. As shown in
It is important to note that the mechanical features described above that allow the angular adjustments of toe and camber could also be used on a conventional trailer. While the invention has been shown and described with respect to specific embodiments thereof, this is for the purpose of illustration rather than limitation, and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art within the intended spirit and scope of the invention as set forth in the appended claims.
Claims
1. A sub-frame assembly mountable to a frame of a trailer, the sub-frame assembly comprising:
- two or more frame members;
- one or more cross members; and
- one or more stub torsion axle assemblies mounted to the sub-frame assembly, each of said stub torsion axle assemblies having a stub axle, a torsion arm, a spindle extending from said torsion arm for mounting one of said wheels, and a distal end for mounting to the trailer frame,
- the stub axle comprising a housing, a stub shaft within the housing and connected to the torsion arm, and at least one resilient member compressed between the stub shaft and the housing,
- wherein the at least one resilient member resists rotation of the torsion arm.
2. The frame assembly of claim 1 wherein the stub torsion axle assembly is rotatably mounted to the cross member whereby the camber angle of the wheel assembly may be adjusted.
3. The frame assembly of claim 1 further comprising one or more shim plates for reception between the cross member and the stub torsion axle assembly for allowing adjustment of the toe angle of the wheel.
4. (canceled)
5. A trailer assembly comprising:
- a frame including two or more frame members and one or more cross members;
- two or more stub torsion axle assemblies, each of said stub torsion axle assemblies having a stub axle, a torsion arm, a spindle extending from said torsion arm for mounting a wheel, and a distal end for mounting to the frame;
- the stub axle comprising a housing, a stub shaft within the housing and connected to the torsion arm, and at least one resilient member compressed between the stub shaft and the housing;
- wherein the at least one resilient member resists rotation of the torsion arm and further wherein at least one of the wheel toe angle and wheel camber angle is adjustable.
6. The trailer assembly of claim 5 further comprising one or more shim plates for reception between the cross member and the stub torsion axle assembly for allowing adjustment of the toe angle of the wheel.
7. The trailer assembly of claim 5 wherein the distal end is rotatably mounted to the cross member whereby the camber angle of the wheel assembly may be adjusted.
8-10. (canceled)
11. The trailer assembly of claim 5 further comprising a sub-frame assembly, wherein said stub torsion axle assembly is mounted to the sub-frame assembly, and wherein said sub-frame assembly is mounted to the frame assembly.
12. The trailer assembly of claim 11 wherein the frame assembly further comprises frame members having a reduced cross sectional area relative to frame members of the sub-frame assembly.
13. A trailer assembly comprising:
- a frame including two or more frame members and one or more cross members;
- two or more stub torsion axle assemblies, each of said stub torsion axle assemblies having a torsion arm, a spindle extending from said torsion arm for mounting a wheel, and a distal end extending from said stub torsion axle assembly for mounting to the frame; wherein said frame has an adjustable size.
14. The frame assembly of claim 1 wherein said frame further comprises two or more indexing holes, a connecting member for connecting said stub torsion axle assembly to the frame and said connecting member being received in one of the indexing holes for allowing adjustment of the camber angle of the wheel.
15. The trailer assembly of claim 5 wherein said frame further comprises two or more indexing holes, a connecting member for connecting said stub torsion axle assembly to the frame and said connecting member being received in one of the indexing holes for allowing adjustment of the camber angle of the wheel.
16. The trailer assembly of claim 5, comprising means for adjusting the camber angle of the wheel.
17. The trailer assembly of claim 5 further comprising means for adjusting the toe angle of the wheel.
18. The trailer assembly of claim 5 further comprising means for adjusting the length or width of the frame.
19. The trailer assembly of claim 5 further comprising means for adjusting the toe angle of the wheel and means for adjusting the camber angle of the wheel.
20. The trailer assembly of claim 7 further comprising one or more shim plates between the cross member and the distal end, the selected presence of which causes a change of the toe angle of the wheel.
21. A sub-frame assembly mountable to a trailer frame, the sub-frame assembly comprising:
- a. at least two parallel frame members;
- b. at least one cross member extending between the parallel frame members;
- c. at least two axle assemblies attached to the cross member, each axle assembly having a bracket and capable of having a wheel mounted thereon;
- d. a first member rotatably mounted to the axle assembly; and
- e. a connecting member for connecting the bracket of the axle assembly to the cross member and the first member;
- wherein rotation of the first member results in a change in the camber angle of the wheel.
22. The sub-frame assembly of claim 21, wherein the first member is a cam member comprising an offset hole for receiving the connecting member therein for connecting the axle assembly, the cam member, and the cross member together.
23. The sub-frame assembly of claim 22, wherein the bracket comprises a slot, and the cam member further comprises a projection in communication with the slot; wherein rotation of the cam member causes engagement of the projection with the bracket, causing the change in the camber angle of the wheel.
24. The sub-frame assembly of claim 21, further comprising one or more shim plates insertable between the bracket and the cross member for adjusting toe angle of the wheel.
Type: Application
Filed: Sep 21, 2006
Publication Date: Jan 18, 2007
Inventors: James Tuthill (Elkhart, IN), John Poague (Elkhart, IN)
Application Number: 11/524,728
International Classification: B60G 5/00 (20060101); B62D 17/00 (20060101); B60G 7/02 (20060101);