Patent ID: 8857593

Claim:
A clutch for a vehicle transmission, comprising: at least one clutch plate; a piston plate displaceable for engaging and disengaging the at least one clutch plate to form a torque path through the at least one clutch plate; a chamber, partially formed by the piston plate for receiving and discharging fluid to displace the piston plate; a snap-spring displaceable between first and second equilibrium positions; a hydraulic valve, including: a housing with a first port for connection to a source of pressurized hydraulic fluid and a second port in fluid communication with the chamber; a displaceable valve piston; and, a valve spring; wherein: in the first equilibrium position the snap-spring holds the valve piston in an open position to enable fluid flow from the source of pressurized hydraulic fluid to the chamber via the first and second ports; and, in the second equilibrium position the snap-spring holds the valve piston in a closed position compressing the valve spring; an overstroke spring, wherein moving from the first equilibrium position to the second equilibrium position comprises displacing the overstroke spring; and an overstroke piston, wherein the overstroke piston displaces the overstroke spring in response to hydraulic fluid pressure greater than a normal operating pressure for the clutch.