A hydrostatic clutch system for dually charging the accumulators while speeding up and slowing down. The hydrostatic clutch system includes a hydraulic pump having a pump housing with openings therein; a manifold/end cover; and a fluid circuit assembly in operable communication with the hydraulic pump. The hydrostatic clutch system may be used with at least one transmission or gear set in operable communication with the hydrostatic clutch. The hydrostatic clutch system may be used to create a variable speed from a fixed input speed. The hydrostatic clutch system may also be used as a hybrid system by changing the pump into a motor for launch and for powering the vehicle with the engine disconnected using accumulated hydraulic pressure. The hydrostatic clutch system captures the resistance of the weight of the vehicle in order to make power while the vehicle is accelerating.

A power transmission system (10) for a hybrid vehicle, the power transmission system (10) includes a transmission (TM, 20), a clutch (18), a motor (MG), an engine (14), a first oil pump (44), a second oil pump (68), a first hydraulic circuit in which the first oil pump (44) is provided, and a second hydraulic circuit in which the second oil pump (68) is provided. The motor (MG) is connected to a driving wheel (26) through the transmission (TM, 20). The engine (14) is connected to the motor (MG) through the clutch (28). The first oil pump (44) supplies oil to the transmission (20). The second oil pump (68) supplies oil to the motor (MG) and the clutch (28). The second hydraulic circuit is independent from the first hydraulic circuit. Selected drawing.

A hydraulic control system for a multiple mode electro-mechanical drive unit of a motor vehicle includes multiple torque transmitting mechanisms each including at least one friction clutch. Multiple clutch control valves are individually in fluid communication with one of the torque transmitting mechanisms and are operable when actuated to change a condition of the torque transmitting mechanisms from a clutch disconnected condition to a clutch engaged condition. Solenoid valves are individually paired with and in fluid communication with one of the clutch control valves. A normally open variable force solenoid valve is in fluid communication with the solenoid valves. Operation of the variable force solenoid valve sets a hydraulic pressure between any of the solenoid valves in an open condition and its paired clutch control valve.

A work vehicle includes a driver's seat supported to a frame unit, a first hydraulic stepless speed changing device transmitting power to a first drive wheel, a second hydraulic stepless speed changing device transmitting power to a second drive wheel, and an oil tank. A bridge beam extending in a vehicle body transverse direction is provided between a cable harness extending in the vehicle body transverse direction and a hydraulic passage connecting the second hydraulic stepless speed changing device to the oil tank.

A magnetorheological (MR) actuator device comprising two or more MR actuator units. Each of the MR actuator units may include a motor, an MR fluid clutch apparatus operatively coupled to the motor to receive torque from the motor, the MR fluid clutch apparatus operable to generate a variable amount of torque transmission when subjected to a magnetic field. An output member is provided, a transmission operatively coupling the at least two MR actuator units to the output member, for the output member to receive torque from the MR actuator units. A controller for controlling the two or more MR actuator units to drive the output member, the controller driving the output member in at least an antagonistic mode in which the MR actuator units transmit torque in opposite directions to the output member. A collaborative mode may be provided to combined the torque of the two or more MR actuator units in a common direction on the output member.

A magnetorheological (MR) actuator device comprising two or more MR actuator units. Each of the MR actuator units may include a motor, an MR fluid clutch apparatus operatively coupled to the motor to receive torque from the motor, the MR fluid clutch apparatus operable to generate a variable amount of torque transmission when subjected to a magnetic field. An output member is provided, a transmission operatively coupling the at least two MR actuator units to the output member, for the output member to receive torque from the MR actuator units. A controller for controlling the two or more MR actuator units to drive the output member, the controller driving the output member in at least an antagonistic mode in which the MR actuator units transmit torque in opposite directions to the output member. A collaborative mode may be provided to combined the torque of the two or more MR actuator units in a common direction on the output member.

A viscous clutch (20) includes a housing assembly (28), a rotor assembly (26), a reservoir (38) to hold a supply of a shear fluid, a working chamber (40) operatively positioned between the housing assembly and the rotor assembly, and a fluid return bore (26-1B) that optionally extends radially through at least an outer diameter portion of the rotor assembly to the working chamber. Selective introduction of the shear fluid to the working chamber facilitates selective torque transmission between the housing assembly and the rotor assembly. The fluid return bore can form at least a portion of a fluid return path (50) from the working chamber to the reservoir.

A viscous clutch (20) includes a housing assembly (28), a rotor assembly (26), a reservoir (38) to hold a supply of a shear fluid, a working chamber (40) operatively positioned between the housing assembly and the rotor assembly, and a fluid return bore (26-1B) that optionally extends radially through at least an outer diameter portion of the rotor assembly to the working chamber. Selective introduction of the shear fluid to the working chamber facilitates selective torque transmission between the housing assembly and the rotor assembly. The fluid return bore can form at least a portion of a fluid return path (50) from the working chamber to the reservoir.

A viscous clutch (20) includes a housing assembly (28), a rotor assembly (26), a reservoir (38) to hold a supply of a shear fluid, a working chamber (40) operatively positioned between the housing assembly and the rotor assembly, and a fluid return bore (26-1B) that optionally extends radially through at least an outer diameter portion of the rotor assembly to the working chamber. Selective introduction of the shear fluid to the working chamber facilitates selective torque transmission between the housing assembly and the rotor assembly. The fluid return bore can form at least a portion of a fluid return path (50) from the working chamber to the reservoir.

A viscous clutch (20) includes a housing assembly (28), a rotor assembly (26), a reservoir (38) to hold a supply of a shear fluid, a working chamber (40) operatively positioned between the housing assembly and the rotor assembly, and a fluid return bore (26-1B) that optionally extends radially through at least an outer diameter portion of the rotor assembly to the working chamber. Selective introduction of the shear fluid to the working chamber facilitates selective torque transmission between the housing assembly and the rotor assembly. The fluid return bore can form at least a portion of a fluid return path (50) from the working chamber to the reservoir.