Hydraulically operated continuously variable transmission.

摘要

A hydraulically operated continuously variable transmission comprises a hydraulic pump (P) and a hydraulic motor (M) having a motor cylinder (70) including an integral tubular member (112). A distribution disc (80) is coupled to the motor cylinder (70) at one end of the tubular portion and has oil passages (81,82) communicating with the hydraulic pump (P) and the hydraulic motor (M). A hollow fixed shaft (91) is inserted in the tubular member (112), and a distribution ring (92) is axially movably mounted on the fixed shaft (91) and has an end face slidably held against the distribution disc.(80). A mechanical seal assembly (118) includes an annular rotatable seal member (115) rotatably disposed in the tubular member (112), and an annular fixed seal member (116) axially movably, but nonrotatably, mounted on the fixed shaft (91). A compression spring (117) is disposed between the fixed seal member (115) and the distribution ring (92) and is resiliently extensible for applying a preload to abut an axial end face of the fixed seal member (115) against an axial end face of the rotatable seal member (116) and a preload to abut the end face of the distribution ring (92) against the distribution disc (180).