SNOWMOBILE FRAME ASSEMBLY

Abstract

A snowmobile rear suspension is shown comprised of a linear force element (LFE) positioned outside the envelope of the snowmobile endless track. The snowmobile frame includes a chassis mounted to a tunnel, where the chassis includes a central mounting bracket. The LFE is attached at one end to the bracket and at the other end to a bell crank. The bell crank is operatively connected to the slide rails. When the slide rails collapse in normal operation, the bell crank strokes the LFE, and the suspension is progressive throughout the range.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present snowmobile will now be discussed with reference to the drawings, where:

FIG. 1 shows a diagrammatical view of a conventional snowmobile suspension system in full rebound;

FIG. 2 shows a diagrammatical view of a conventional snowmobile suspension system in full jounce;

FIG. 3 shows the diagrammatical view of a conventional snowmobile suspension system according to FIG. 1 and 2, with a front load applied;

FIG. 4 shows the diagrammatical view of a conventional snowmobile suspension system according to FIG. 1 and 2, with a rear load applied

FIG. 6 shows a comparison curve of the prior art versus the improved suspend with a rear load;

FIG. 7 shows a comparison curve of the prior art versus the improved suspend with a front load;

FIG. 8 shows a diagrammatical perspective view of the suspension of the present invention;

FIG. 9 shows a diagrammatical plan view of the suspension of FIG. 8;

FIG. 10 shows a diagrammatical plan view of the suspension of the present invention at full rebound;

FIG. 11 shows a diagrammatical plan view of the suspension of the present invention at full jounce;

FIG. 12 shows a diagrammatical perspective view of an alternate suspension;

FIG. 13 shows a diagrammatical plan view of the suspension of the present invention retro-fit on an existing suspension;

FIG. 14 shows a diagrammatical plan view of another suspension of the present invention retro-fit on an existing suspension;

FIG. 15 shows a perspective view of the suspension of the present invention applied to a tunnel and to slide rails;

FIG. 16 shows a perspective view of the suspension of FIG. 16, with the chassis and tunnel removed;

FIG. 17 shows a plan view of the FIG. 16 embodiment;

FIG. 18 shows an enlarged perspective view of FIG. 16, showing the front suspension mounts;

FIG. 19 shows an enlarged view of the connection of the front suspension mounts of FIG. 18 to the slide rails;

FIG. 20 shows a partial sectional view of one driveshaft assembly;

FIG. 21 shows the driveshaft assembly of FIG. 20, partially disassembled;

FIG. 22 shows a partial sectional view of another possible driveshaft assembly;

FIG. 23 shows the driveshaft assembly of FIG. 22, partially disassembled;

FIG. 24 shows an enlarged perspective view of FIG. 16, showing the rear suspension mounts to the slide rails;

FIG. 25 shows an enlarged perspective view showing the pivotal sliding coupling connection of the rear suspension mounts to the slide rails;

FIG. 26 shows an enlarged perspective view of the rear deflector shield;

FIG. 27 shows an enlarged perspective view of the rear chassis of FIG. 15 removed;

FIG. 28 is a diagrammatical view shows the force vectors applied to the suspension system;

FIG. 29 is a perspective view of an alternate rear chassis removed;

FIG. 30 shows the rear chassis of FIG. 29 attached to a tunnel;

FIG. 31 shows the rear chassis of FIG. 30 with a seat mounting frame;

FIG. 32 shows a seat bun mounted on the seat frame of FIG. 31;

FIG. 33 shows an alternate tunnel mounted seat frame; and

FIG. 34 shows a seat bun mounted on the seat frame of FIG. 33.

Claims

1. A snowmobile, comprising: a tunnel;a chassis structurally mounted to the tunnel;slide rails for mounting endless track;at least one front linkage operatively connecting the slide rails to one of the tunnel or chassis; andat least one rear linkage operatively connecting the slide rails to the chassis.

2. The snowmobile of claim 1, wherein at least one linear force element (LFE) is positioned between the chassis and the rear linkage.

3. The snowmobile of claim 2, wherein the at least one LFE is positioned outside of the envelope defined by the endless track.

4. The snowmobile of claim 3, wherein the at least one LFE is positioned above the tunnel.

5. The snowmobile of claim 4, wherein the chassis is comprised of framing attached to the exterior of the tunnel, and comprises a central bracket to which one end of the LFE is attached.

6. The snowmobile of claim 5, further comprising a drive shaft mounted transversely through the tunnel, and wherein the front linkage is attached to the tunnel, at a position coaxial with the drive shaft.

7. The snowmobile of claim 6, wherein the chassis further comprises load arms directing forces along a load path which are coincident with a rotational axis of the drive shaft.

8. The snowmobile of claim 1, wherein the chassis further comprises tubes attached to and straddling the tunnel, the tubes extending substantially vertically.

9. The snowmobile of claim 8, wherein the tubes define a steering hoop.

10. The snowmobile of claim 1, wherein the chassis further comprises a seat mount frame.

11. The snowmobile of claim 1, comprising two front linkages, each linkage connecting one slide rail to one of the tunnel or chassis, the front linkages being interconnected to the slide rails by a clevis which straddles the slide rails.

12. The snowmobile of claim 1, further comprising at least one linear force element (LFE) positioned above the endless track.

13. The snowmobile of claim 12, further comprising a seat mounted above the LFE.

14. A snowmobile, comprising: a tunnel;a chassis structurally mounted to the tunnel;slide rails for mounting endless track, and being operatively connected to one of the tunnel or chassis about a rotational axis;at least one linear force element (LFE) positioned intermediate the chassis and slide rails;whereby at least some of the force exerted on the chassis is directed along a load path coincident with the rotational axis.

15. The snowmobile of claim 14, further comprising at least one front linkage operatively connecting the slide rails to the tunnel or chassis; and at least one rear linkage operatively connecting the slide rails to the chassis.

16. The snowmobile of claim 15, wherein the at least one LFE is positioned between the chassis and the rear linkage.

17. The snowmobile of claim 16, wherein the at least one LFE is positioned outside of the envelope defined by the endless track.

18. The snowmobile of claim 17, wherein the at least one LFE is positioned above the tunnel.

19. The snowmobile of claim 16, wherein the chassis is comprised of framing attached to the exterior of the tunnel, and comprises a central bracket to which one end of the LFE is attached.

20. The snowmobile of claim 19, further comprising a drive shaft mounted transversely through the tunnel at a position coaxial with the rotational axis.

21. The snowmobile of claim 20, wherein the chassis further comprises load arms directing forces along a load path which is coincident with the drive shaft rotational axis.

22. The snowmobile of claim 14, wherein the chassis further comprises tubes attached to and straddling the tunnel, the tubes extending substantially vertically.

23. The snowmobile of claim 22, wherein the tubes define a steering hoop.

24. The snowmobile of claim 15, comprising two front linkages, each linkage connecting one slide rail to the tunnel or chassis, the front linkages being interconnected to the slide rails by a clevis which straddles the slide rails.

25. A snowmobile, comprising: a tunnel;a chassis structurally mounted to the tunnel, comprising framing attached to the exterior of the tunnel, and further comprising a central bracket;slide rails for mounting endless track being operatively connected to the tunnel or the chassis; andat least one linear force element (LFE) positioned intermediate the chassis central bracket and slide rails.

26. The snowmobile of claim 25, wherein the chassis further comprises tubes attached to and straddling the tunnel, the tubes extending substantially vertically.

27. The snowmobile of claim 25, wherein the tubes define a steering hoop.

28. The snowmobile of claim 25, further comprising at least one front linkage operatively connecting the slide rails to the tunnel; and at least one rear linkage operatively connecting the slide rails to the chassis.

29. The snowmobile of claim 28, further comprising a drive shaft mounted transversely through the tunnel, and wherein the front linkage is attached to the tunnel, at a position coaxial with the drive shaft.

30. The snowmobile of claim 29, wherein the chassis further comprises load arms directing forces along a load path which is coincident with the drive shaft rotational axis.

31. The snowmobile of claim 25, wherein the at least one LFE is positioned outside of the envelope defined by the endless track.

32. The snowmobile of claim 31, wherein the at least one LFE is positioned above the tunnel.

33. The snowmobile of claim 28, comprising two front linkages, each linkage connecting one slide rail to the tunnel or chassis, the front linkages being interconnected to the slide rails by a clevis which straddles the slide rails.