Snowmobile with hydraulic device

Claim 1

In a snowmobile comprising a body having a pair of ground engaging skis at the front end portion thereof, a bogey wheel track assembly including a bogey wheel frame, a plurality of bogey wheels journalled on said frame, a plurality of sprockets, at least one of which is driven, a ground engaging endless flexible track trained about said bogey wheels and sprockets, an internal combustion engine having an output shaft, a variable displacement rotary hydraulic pump having an input shaft, drive means interconnecting said output shaft of the engine with the input shaft of the hydraulic pump, a reservoir containing hydraulic fluid, a supply conduit interconnecting said reservoir and pump in communicating relation with each other, a pump bleeder conduit having an internal diameter less than the diameter of said supply conduit and interconnecting said pump in communicating relation with said reservoir, a variable displacement reversing rotary hydraulic motor having an output shaft, means connecting the output shaft of said variable displacement motor with the driven sprocket of the bogey wheel assembly, a pair of conduits connecting said pump and motor in communicating relation with each other to permit hydraulic fluid to flow therebetween, a motor bleeder conduit connecting said hydraulic motor in communicating relation with said reservoir and having a diameter smaller than the diameter of conduits connecting the pump with said motor, and a control valve connected in communicating relation with respect to said conduits, said valve controlling the volume and direction of flow of the hydraulic fluid between said pump and motor, and being adjustable between forward, reverse and neutral positions, said valve when in the forward position controlling the flow of hydraulic fluid to said motor to cause the bogey wheel assembly to be driven in a forward direction, and when in a reverse position controlling the flow of fluid to the motor to drive the bogey wheel assembly in the reverse direction, and when in the neutral position permitting the flow of fluid to bypass said motor and be returned to the reservoir through said bleeder conduit.