SE302391

1,021,873. Hydrostatic transmissions; valves. Y. KUZE. Sept. 7, 1962 [Sept. 16, 1961], No. 34312/62. Headings F2C, F2D and F2V. [Also in Division F1] A hydrostatic . transmission comprises a swash-plate pump and motor unit, the inclination of the pump swash-plate 4 being variable by hydraulic means to vary the transmission ratio, and the motor swash-plate being adjusted by hydraulic means for forward or reverse drive or a valve controlling supply and exhaust of liquid to the motor being actuated for determining forward and reverse. As shown in Fig. 1, a pump cylinder barrel 26 is fast with an input shaft 25, and the pump swash-plate 4 is pivotally mounted in a stationary housing 2 by means of diametrically arranged pins 1. The motor cylinder barrel 126 is carried by an output shaft 125 and the motor swash-plate 104 carries diametrically arranged pins 101 rotatably mounted in the stationary housing. A valve plate 21 for the pump is mounted on an eccentric projection 20 of a sleeve 17 mounted in the casing 2. Ports 23 concentrically disposed about the projection 20 register with the pump cylinders on the intake strokes of their pistons 24, and the cylinders on the discharge strokes of the pistons register with a crescent-shaped space 28 formed between the periphery of the plate 21 and an annular member 27 carried by the pump cylinder barrel. Liquid from the space 28 is discharged through passages 32 in the member 27 to an annular space 31 and thence through passages 33, 30, 130, 133 provided in a member 16 fast with the housing 2, to the motor. The valve plate 121 for the motor is similar to the pump valve plate and is carried by an eccentric projection 120 of the sleeve 17, liquid discharged by the pump being supplied to the space 128 between the periphery of the valve plate 121 and an annular member 127 fast with the motor cylinder barrel. Liquid is discharged from the motor cylinders through ports 123 in the valve plate to the hollow interior of the sleeve 17 and from thence is supplied through the ports 23 in the valve plate 21 to the intake side of the pump. Make-up liquid is supplied by a pump p from a reservoir T to a port 15 in the housing 2 and thence through a passage in the member 16 and ports 19 to the interior of the sleeve 17. Liquid from the pressure side of the transmission is supplied through a port 34 to a valve housing 35 containing valves 36, 46, respectively, controlling the supply of liquid to a differential piston 6 controlling the pum