SEMI-ROTARY HYDRAULIC ACTUATOR

摘要

An actuator (10) for rotating a shaft (11) includes a housing (12) having a first port (27), a second port (28) and a drive track (26). A first drive means (29) is coupled to the first port (27) and a second drive means (30) is coupled to the second port (28). An array of balls (33) which is spaced apart by spacers (34) define a drive train extending from one drive means (29) to the second drive means (30) via the drive track (26). A drive pin (14) which extends outwardly from the shaft (11) is connected to the drive train and the first and second drive means (29 and 30) are driven so that the drive train will rotate the drive pin (14) and hence the shaft (11).