Yamaha Hatsudoki Kabushiki Kaisha

Yamaha Motor Corporation, USA

Takahiko Kubota

Masanori Yoshihara

Kaoru Haruna

Kiyoteru Suzuki

Tadashi Takayama

Ronald Ruzewski

Jeremy Fohrenkam

Provided is a suspension system capable of expanding one of an oil chamber and a gas chamber of an intermediate unit and contracting the other when a damper compresses or expands without generating friction in the intermediate unit. The intermediate unit includes an intermediate case having an intermediate oil chamber connected to an oil chamber of a right damper and the oil chamber of a left damper and an intermediate gas chamber, and a diaphragm made of a flexible material, which partitions the intermediate oil chamber and the intermediate gas chamber.

Suspension system and vehicle

In a suspension system in which the oil chambers of two dampers are connected, the responsiveness of the dampers can be adjusted. A suspension system has a left damper, a right damper, and an intermediate unit. A case of the intermediate unit has an intermediate oil chamber connected to an oil chamber of the left damper and the oil chamber of the right damper and an intermediate gas chamber. The intermediate oil chamber and the intermediate gas chamber are partitioned by a diaphragm. The intermediate unit has a capacity adjustment mechanism including a movable portion of which the position can be changed. The capacity adjustment mechanism adjusts the capacity of the intermediate gas chamber by changing the position of the movable portion.

A snowmobile includes a track belt and a drive sprocket that couple with each other to propel the snowmobile with reduced noise and wear. The track belt has a plurality of driven projections and a plurality of driven windows at regular intervals along the direction of movement of the track belt. The drive sprocket has a projection drive portion and for engaging the driven projections and a window drive portion for engaging edges of the driven windows. In some embodiments, the driven projection, the driven window, the projection drive portion, and the window drive portion can be positioned so that the time when the driven projection and the projection drive portion contact each other is different from the time when the edge of the driven window and the window drive portion contact each other. Additionally, in some embodiments a damper is placed between the drive sprocket and the drive shaft. In some embodiments, a damper is coupled with at least a portion of a peripheral surface of at least one of the drive sprocket, the projection drive portion, and the window drive portion.

Snowmobile

A front suspension arm is formed such that it is less likely to collide with obstacles exposed above the surface over which the associated vehicle is operated. The arm also has a greater strength against impact forces from the front. In one configuration, the front suspension arm has a relatively straight portion that is positioned on a body side and the front suspension arm has a bent portion that is formed on the ground contacting element side. The front suspension arm can have two arms having an oblong or oval shape in cross section.

Front suspension arms

A snowmobile has a pair of steering skis. Each ski has an elongated primary section that has a bottom surface. The bottom surface extends generally horizontally and warps upward at a forwardly end. A keel section extends along the primary section. The keel section projects downwardly from the primary section. A pair of generally vertical sections extends along the primary section. Each generally vertical section has a generally vertical surface that extends upwardly from a side edge of the bottom surface of the primary section. In one embodiment, a pair of generally horizontal sections extends along the primary section. Each horizontal section has a generally horizontal surface that extends generally horizontally outward from a top end of the generally vertical surface of each generally vertical section.

Steering ski for snow vehicle

A number of embodiments of snowmobile suspensions for the drive belt of the snowmobile. The suspension includes a single cushioning unit that has its opposite ends loaded by a linkage system that is interposed between a guide rail and a frame of the snowmobile. At least one of these pivotal connections is adjustable, and the adjustment is provided in a manner so that it can be made without changing the effective length of the cushioning unit during adjustment. In addition, a number of the embodiments permit the adjustment to be made at one side of the snowmobile.

Rear suspension for snowmobiles

An adjustment structure for the cushion unit of a snowmobile suspension system. The adjustment arrangement includes a mounting for the cushioning unit that is defined by a bolt and a pair of mount brackets having guide apertures formed therein. The bolt and guide aperture surfaces are treated so as to avoid shifting of the mechanism under the weight of the snowmobile when the mounting bolt is loosened for adjustment purposes.

Drive belt suspension for snowmobile

A snowmobile and more particularly to an improved suspension arrangement for a snowmobile that provides an elastic stop for limiting the movement of the drive belt upwardly relative to the frame assembly and which operates independently of the cushioning units so as to avoid undue loading and wear of them

Growing community of inventors

Shizuoka, Japan

Takahiko Kubota