Torque transmission device for powertrain of motor car, has pressure controller that controls pump to vary supply of fluid by varying rotational speed of pumping portions based on pressure in suction space

摘要

The device (16) has a pump (22) having pumping portions (24,26), a suction space and a pressure chamber. The pumping portions are rotatable with respect to each other to transfer a rotational torque of pumping portions to hydraulic fluid a based on pumping pressure of pump so that the hydraulic fluid is transferred to the pressure chamber from suction space of the pump. A pressure controller controls pump to vary the supply of fluid by varying the rotational speed of the pumping portions based on the pressure in suction space.