Snowmobile suspension

Claim 2

In combination with a snowmobile frame having an endless belt thereunder which is end sprocket driven for propulsion of the frame thereon; a suspension for said frame, comprising: a wheelsupported resilient framework within said belt and riding the ground-supported face thereof; said framework resiliently supporting the front and rear end of said frame and carrying idler sprockets for the opposite end rotation of said belt; adjustments on said frame for end-moving the framework and said idler sprockets for frame-supporting resiliency of the framework, and to maintain the belt tight on said sprockets, and two wheelsupported resilient rails forming the framework and underlying said frame; one of the ends of said rails being bent upwardly to connect with a cross shaft, the outer ends of which pass through slots in the frame walls to connect with said adjustments on the exterior of the frame, said adjustments operating to move the ends of said cross shaft along said slots, in the tightening and loosening of said belt.

Claim 3

A snowmobile frame suspension as defined in claim 1, wherein a cross axle is mounted on the rear end of the framework to rotatably support said idler sprockets, and the outer ends of said axle resiliently support the rear part of said frame, through shock absorbers.

Claim 4

A snowmobile suspension as defined in claim 1, wherein the front ends of said rails are separately hinged to the rear parts thereof and resiliently reinforced against hinging.

Claim 5

In combination with a snowmobile frame; a suspension therefor, comprising: a resilient wheel-supported framework; sprockets rotatably mounted across one end of said framework, and said end resiliently supporting one end of said snowmobile frame, while the opposite end of the framework supports the opposite end of said frame; the central part of the framework downwardly sprung for resiliency between the frame and said framework supporting wheels; an endless belt encircling said suspension, with one end looped over and meshing with said sprockets, another end thereof looped over and meshing with further sprockets rotatably carried bY the frame, and said supporting wheels riding the lower interior of the belt; means carried by the frame for power driving said latter sprockets; adjustment means at one end of the frame support for varying the resiliency of the framework to tighten or loosen the belt on said sprockets, two wheel-supported resilient rails forming the framework and underlying said frame; one of the ends of said rails being bent upwardly to connect with a cross shaft, the outer ends of which pass through slots in the frame walls to connect with said adjustments on the exterior of the frame, said adjustments operating to move the ends of said cross shaft along said slots, in the tightening and loosening of said belt.

Claim 6

In combination with a snowmobile frame; a suspension therefor, comprising: a resilient wheel-supported framework; sprockets rotatably mounted across one end of said framework, and said end resiliently supporting one end of said snowmobile frame, while the opposite end of the framework supports the opposite end of said frame; the central part of the framework downwardly sprung for resiliency between the frame and said framework supporting wheels; an endless belt encircling said suspension, with one end looped over and meshing with said sprockets, another end thereof looped over and meshing with further sprockets rotatably carried bY the frame, and said supporting wheels riding the lower interior of the belt; means carried by the frame for power driving said latter sprockets; adjustment means at one end of the frame support for varying the resiliency of the framework to tighten or loosen the belt on said sprockets, two wheel-supported resilient rails forming the framework and underlying said frame; one of the ends of said rails being bent upwardly to connect with a cross shaft, the outer ends of which pass through slots in the frame walls to connect with said adjustments on the exterior of the frame, said adjustments operating to move the ends of said cross shaft along said slots, in the tightening and loosening of said belt.

Claim 7

A snowmobile frame suspension as defined in claim 4, wherein a cross axle is mounted on the rear end of the framework to rotatably support said idler sprockets, and the outer ends of said axle resiliently support the rear part of said frame, through shock absorbers.

Claim 8

A snowmobile suspension as defined in claim 4, wherein the front ends of said rails are separately hinged to the rear parts thereof and resiliently reinforced against hinging.

Claim 9

In combination with a snowmobile frame having an endless belt thereunder and which is front sprocket-driven for propulsion of said frame; a suspension therefor, comprising: a pair of spaced tapered and resilient rails supported on off-set wheels therealong to provide a portable framework below said frame; the rear wide ends of said rails each forked and carrying a cross axle therebetween, and the front narrow ends of the rails turned upwardly at an angle and secured to a cross shaft; said cross axle rotatably mounting a pair of sprockets each of which rotate in one of said forks; the outer ends of the cross axle each connected with a shock absorber on the snowmobile frame for rear support thereof; the ends of said cross shaft passing through slots in the frame sides and secured to brackets for front support of the snowmobile frame from the framework; a drive shaft rotatably mounted across the front part of the snowmobile frame and carrying a pair of spaced sprockets therealong; sprocket-receiving tracks along each side of said belt; said belt encircling the suspension with the tracks thereof meshing with the sprockets of the drive shaft and of the cross axle, and with the offset wheels riding the lower interior face thereof on either side of the tracks; means on said brackets for adjustably shifting the ends of the cross shaft along said slots for increasing the frame support resiliency of the framework, and tightening the belt on said sprockets; and means for driving said drive shaft.

Claim 10

In combination with a snowmobile frame having an endless belt thereunder and which is front sprocket-driven for propulsion of said frame; a suspension therefor, comprising: a pair of spaced tapered and resilient rails supported on off-set wheels therealong to provide a portable framework below said frame; the rear wide ends of said rails each forked and carrying a cross axle therebetween, and the front narrow ends of the rails turned upwardly at an angle and secured to a cross shaft; said cross axle rotatably mounting a pair of sprockets each of which rotate in one of said forks; the outer ends of the cross axle each connected with a shock absorber on the snowmobile frame for rear support thereof; the ends of said cross shaft passing through slots in the frame sides and secured to brackets for front support of the snowmobile frame from the framework; a drive shaft rotatably mounted across the front part of the snowmobile frame and carrying a pair of spaced sprockets therealong; sprocket-receiving tracks along each side of said belt; said belt encircling the suspension with the tracks thereof meshing with the sprockets of the drive shaft and of the cross axle, and with the offset wheels riding the lower interior face thereof on either side of the tracks; means on said brackets for adjustably shifting the ends of the cross shaft along said slots for increasing the frame support resiliency of the framework, and tightening the belt on said sprockets; and means for driving said drive shaft.

Claim 11

A snowmobile suspension as defined in claim 7, wherein the front ends of said rails are separately hinged to the rear parts thereof and resiliently reinforced against hinging.