Abstract: A continuously variable friction drive transmission has expandable fluid housing members on both the input shaft and the output shaft. The housing members are in fluid communication with a control valve which is operable to establish the fluid pressures in the housings. The housings are maintained in frictional engagement by the internal fluid pressure such that power can be transmitted between the shafts. The drive ratio between the shafts is determined by the internal pressures of the housings which establish the outer diameters thereof. The drive ratio is changed by changing one or both of the internal fluid pressures.

Abstract: A vehicle having a plurality of ground engaging wheels has included, in at least one of said wheels, a hydraulic pump/motor device. The hydraulic fluid for the pump/motor device is stored in a toroidal tire portion of the wheel while the pump/motor is disposed in a hub portion of the wheel. The hydraulic fluid is drawn from a sump reservoir in the tire portion and is pumped to a high pressure liquid/gas accumulator in the tire portion during vehicle braking. When desired, the high pressure fluid is returned through the pump/motor to the sump reservoir during which time the energy of the high pressure fluid is delivered to the vehicle through the motoring action of the pump/motor.