Abstract: The invention relates to a control apparatus for a clutch disc assembly drivingly associated with an engine. Protection from engine stall resulting for inertia loads downstream of the engage clutch disc assembly instantaneously exceeding available engine torque involves sophisticated brakes, intricate sequence controls, and complicated internal clutch control valving. The present apparatus includes a control valve for controllably directing fluid pressure to the clutch disc assembly from a source of fluid pressure. A valve member reciprocally disposed in the control valve is continually urged in a first axial direction. A speed sensor associated with an input member driven by the engine urges the valve member in a direction opposite the first axial direction in response to a decrease in the rotational speed of the input member to a preselected angular velocity slipping the clutch disc assembly.

Abstract: A fluid operated clutch assemblage having axially aligned rotary input and output members, at least one axially movable disc carried by one member and at least one axially movable plate carried by the other member and an axially movable, hydraulically operated piston for causing engagement of the disc and the plate to couple the input and output members. The clutch includes a valve concentric with the input member and axially movable thereon and rotatable therewith. The valve is provided with a first pressure responsive surface and a second pressure responsive surface in bucking relation to the first pressure responsive surface. A spring biases the valve oppositely of the second pressure responsive surface and there is provided an annular, axially expandable chamber including the second pressure responsive surface rotatable with the input member.

Abstract: A control valve for a fluid operated clutch or the like, including a valve body, a first valve mounted for reciprocation in the valve body, a second valve mounted for reciprocation in the valve body and for relative movement with respect to the first valve, one of the valves being concentric with the other, ports in the valves including a throttling port at the interface of the valves, a manual actuator for reciprocally shifting one of the valves, and a rotatable flyweight assembly for reciprocally shifting the other of the valves. Throttled fluid flow from the valve may be directed to a fluid operated clutch to control its capacity and regulate the output speed thereof.