Self-energizing pump for overrunning clutch

A pump assembly comprising:

• a pump housing defining an interior;
• a cylinder rod slidingly received within the interior of the pump housing for pressurizing a hydraulic fluid;
• a cam member adapted for receipt on a shaft such that the shaft is capable of relative rotation with respect to the cam member about a central axis defined by the shaft, the cam member including a cam surface adapted to drivingly slide the cylinder rod with respect to the pump housing upon relative movement of the cam member with respect to the pump housing;
• a rotation coupler carried by the shaft such that the rotation coupler rotates with the shaft, the rotation coupler adapted for limited engagement with the cam member such that rotation of the shaft results in relative movement between the cam member and the pump housing to slide the cylinder rod with respect to the pump housing and pressurize a hydraulic fluid;
• and
• a coil adapted to generate a magnetic field, and wherein the rotation coupler and the cam member are drawn into contact with each other in response to the electromagnetic field generated by the coil such that the cam member is frictionally engaged to the rotation coupler;
• wherein the rotation coupler includes an armature plate having a central opening in which the shaft is received, the armature plate including splines spaced about the central opening for torque-transferring engagement with a splined portion of the shaft.

A pump assembly comprising:

• a pump housing defining an interior;
• a cylinder rod slidingly received within the interior of the pump housing for pressurizing a hydraulic fluid;
• a cam member adapted for receipt on a shaft such that the shaft is capable of relative rotation with respect to the cam member about a central axis defined by the shaft, the cam member including a cam surface adapted to drivingly slide the cylinder rod with respect to the pump housing upon relative movement of the cam member with respect to the pump housing;
• a rotation coupler carried by the shaft such that the rotation coupler rotates with the shaft, the rotation coupler adapted for limited engagement with the cam member such that rotation of the shaft results in relative movement between the cam member and the pump housing to slide the cylinder rod with respect to the pump housing and pressurize a hydraulic fluid;
• wherein the pump assembly is mounted to a differential clutch, wherein the pump housing includes a port for permitting pressurized fluid to channel out of the pump housing, and further comprising a fluid passage extending between the port and a hydraulic piston in the differential for channeling pressurized fluid to the hydraulic piston.

A pump assembly comprising:

• a pump housing defining an interior;
• a cylinder rod slidingly received within the interior of the pump housing for pressurizing a hydraulic fluid;
• a cam member adapted for receipt on a shaft such that the shaft is capable of relative rotation with respect to the cam member about a central axis defined by the shaft, the cam member including a cam surface adapted to drivingly slide the cylinder rod with respect to the pump housing upon relative movement of the cam member with respect to the pump housing;
• a rotation coupler carried by the shaft such that the rotation coupler rotates with the shaft, the rotation coupler adapted for limited engagement with the cam member such that rotation of the shaft results in relative movement between the cam member and the pump housing to slide the cylinder rod with respect to the pump housing and pressurize a hydraulic fluid;
• a pressure regulating system coupled to the pump housing and adapted to limit a pressure for the hydraulic fluid below a design pressure;
• wherein the pressure regulating system includes a valve housing and a compensating valve, the compensating valve including a piston slidable within a piston chamber defined by the valve housing, the piston chamber adapted to receive a pressurized hydraulic fluid from the interior of the pump housing, the piston responsive to the pressurized hydraulic fluid to move towards a pressure-relieving position for the piston, the compensating valve adapted to discharge pressurized fluid from the piston chamber when the piston is in the pressure-relieving position to limit the pressure of the hydraulic fluid below the design pressure.

A clutch assembly for a vehicle comprising:

• a differential housing defining an interior;
• an input shaft rotatably supported within the interior of the differential housing, the input shaft adapted for engagement with a drive system of the vehicle for rotation of the input shaft by the drive system;
• a pump master cylinder, the pump master cylinder defining an interior chamber for receipt of a hydraulic fluid to be pressurized therein;
• a cylinder rod slidingly received within the interior chamber of the pump master cylinder in fluid-tight relation to an inner surface of the pump master cylinder;
• a cam member defining a central opening receiving the input shaft such that the cam member is rotatably supported by the input shaft, the cam member including a ring and a back plate, the ring connected to the back plate such that the ring extends from one side of the back plate, the ring including an outer cam surface having a radius that varies about a circumference of the ring including at least one ramped portion;
• an armature plate defining a central opening receiving the input shaft such that the armature plate is located next to back plate of the cam member, the armature plate and the input shaft engaged to each other such that the armature plate rotates with the input shaft;
• and
• a coil located next to the armature plate and generating an electromagnetic field when activated such that the cam member and the armature plate are drawn into contact with each other, the contact resulting in friction force between the armature plate and cam member back plate during rotation of the armature plate by the input shaft such that the cam member is rotated with respect to the differential housing,
• the cylinder rod and cam member arranged such that the cylinder rod is driven by one of the at least one ramped portions of the cam member when the coil is activated to rotate the cam member with respect to the differential housing.