Abstract: A clutch assembly, including: a secondary piston assembly; a primary piston including a portion located radially outward of the secondary piston assembly; a first chamber at least partially formed by a first side of the primary piston; a second chamber at least partially formed by the secondary piston assembly and a second side of the primary piston; and a check valve connecting the first and second chambers. For a first force applied by fluid in the first chamber: the primary piston remains axially stationary; the fluid flows from the first chamber into the second chamber; and the secondary piston assembly displaces in a first axial direction to contact a clutch pack. For an increase of the first force to a second force: fluid flow between the first and second chambers is blocked by the check valve; and the primary piston and the secondary piston assembly displace in the first axial direction to close the clutch pack.

Abstract: A clutch arrangement for connecting two components, which can rotate relative to one another, of a motor vehicle drive train, in particular for connecting two shafts of a transmission or a shaft to an idler gear rotatably mounted on the shaft. The clutch arrangement has a clutch and an actuator arrangement. The clutch is opened in a first actuator position of an actuator section of the actuator arrangement. The clutch arrangement has a locking device for locking the actuator section in a locked position to keep the clutch closed. The locking device has a slotted-link guide with a first guide section and a second guide section for the actuator section, wherein the locked position can be reached from the first actuator position via the first guide section, and wherein the first actuator position can be reached from the locked position via the second guide section.

Abstract: A clutch including: a first piston displaceable to operate a clutch pack; a second piston; a first fluid chamber partially formed by the pistons, wherein the second piston is displaceable by fluid pressure in the first fluid chamber; and a locking means fixable by the second piston to hold the pack closed. In a preferred embodiment, the locking means includes at least one displaceable ball. In another preferred embodiment, in response to a loss of fluid pressure in the first chamber, the second piston is displaceable to enable displacement of the locking means to open the pack. In a further preferred embodiment, the clutch includes a second chamber, separate from the first chamber and partially formed by the first piston. The first piston is displaceable in response to fluid pressure in the second chamber. The pack remains closed after a loss or reduction of fluid pressure in the second chamber.

Abstract: A torque converter including an impeller clutch with a first portion connected to a cover for the torque converter and a second portion connected to an impeller; and a lever element in contact with the clutch and displaceable to multiply a first force applied to the lever element for operation of the clutch. In some aspects, the converter includes an impeller piston plate engaged with the lever element and displaceable to apply the force to the lever element. In some aspects, the torque converter includes a torus and a charge chamber for the impeller clutch, a second force is associated with a hydraulic pressure to prevent cavitation in the torus, a third force is required to operate the impeller clutch to transmit a desired torque across the impeller clutch, and the multiplied force is at least equal to a sum of the second force and a third forces.