Torque converter clutch with low back pressure

摘要

A torque converter includes an impeller shell and a backing plate defining at least a portion of a first hydraulic chamber, a cover and a piston plate defining at least a portion of a second hydraulic chamber, and a third hydraulic chamber. The third chamber is sealed from the first and second hydraulic chambers such that a hydraulic flow between the third chamber and the other chambers is at least restricted. In some example embodiments, the torque converter includes a turbine, a stator, and an impeller disposed within the first hydraulic chamber, and a lockup clutch including a piston plate. The first chamber is for being pressurized to prevent cavitation in the turbine, stator, or impeller, the second or third chamber is for being pressurized to engage the lockup clutch, and the other of the second or third chamber is for being de-pressurized to reduce a back pressure on the lockup clutch piston plate.

主权项

1. A lockup clutch for a torque converter, the lockup clutch being configured to transmit a torque from a cover to a transmission input shaft of the torque converter, the lockup clutch comprising:
a lockup clutch assembly disposed between the cover and a turbine, the lockup clutch assembly being configured to either allow or block transmission of the torque; and a damper configured to transmit the torque from the lockup clutch assembly to the turbine; the lockup clutch assembly including:
a first plate disposed between the cover and the turbine;a second plate configured to output the torque to the damper;at least one clutch plate configured to transmit the torque between the first plate and the second plate;a backing plate, axially immovable with respect to the cover, disposed between the cover and an inner peripheral part of the turbine, and forming a first chamber;a piston plate, axially movable with respect to the cover, disposed between the cover and the backing plate; the piston being configured to be moved toward the cover by an oil to be supplied to the first chamber to cause the first plate and the clutch plate to be pressed against each other; and,a cover hub fixed to the cover and to an inner peripheral part of the backing plate.