Clutch actuator

Claim 1

A continuously variable transmission comprising: an input shaft driven from a power source carrying a first variable pulley; a second shaft carrying a second variable pulley and a drive belt adapted to transmit power between the input shaft and the second shaft by driveably engaging the first and second pulleys; gear means for transmitting power from the second shaft; clutch means for driveably coupling the gear means to the second shaft; an output shaft; a synchronizer clutch for selectively coupling the gear means to said output shaft; means for actuating the clutch means whereby the synchronizer clutch couples the gear means to said output shaft before the clutch means couples the gear means to the second shaft; the actuator means comprising an actuator body defining a cylinder within which a piston moves between first and second operating positions, the body defining first and second ports spaced from one another; a manual valve for selectively pressurizing the first and second sides of the piston whereby the piston moves within the cylinder in response to a pressure force developed on the pressurized side of the piston; valve means including first lands in said body and registering second lands on the piston for opening communication between the first side of the piston and a first port when said first piston side is pressurized and for opening communication between said second side of the piston and a second port when said second piston side is pressurized, said first and second ports being formed in said actuator body and communicating with said clutch means; and an exhaust port on said piston adapted to register with one of said ports when the piston is in an intermediate position between said first and second operating positions.