Abstract: A transmission includes an accumulator to hold one of more shift elements in an engaged state while an engine is off. The transmission also includes a hydraulic park system that disengages park in response to engagement of two shift elements. In some circumstance, draining the accumulator in an uncontrolled manner in the presence of a failed valve may lead to unintentionally disengaging park. To avoid this, the accumulator is discharged in a controlled manner. Fluid is first transferred from the accumulator to a shift element apply chamber. Then, the fluid is vented from the shift element apply chamber.

Abstract: A transmission includes an accumulator to hold one of more shift elements in an engaged state while an engine is off. The transmission also includes a hydraulic park system that disengages park in response to engagement of two shift elements. In some circumstance, draining the accumulator in an uncontrolled manner in the presence of a failed valve may lead to unintentionally disengaging park. To avoid this, the accumulator is discharged in a controlled manner. Fluid is first transferred from the accumulator to a shift element apply chamber. Then, the fluid is vented from the shift element apply chamber.

Abstract: A park valve includes a slidable end-cap. Under normal circumstances, the end-cap is held in a nominal position by a spring, such as a Belleville spring. The park valve performs a multi-plexing function in which an out-of-park circuit is connected to line pressure when the valve is in an out-of-park position and is vented when the valve is in a park position. In an intermediate position, a hydraulic lock condition may potentially occur. When engaging park, the hydraulic lock condition is prevented by the slidable end-cap.

Abstract: A park valve includes a slidable end-cap. Under normal circumstances, the end-cap is held in a nominal position by a spring, such as a Belleville spring. The park valve performs a multi-plexing function in which an out-of-park circuit is connected to line pressure when the valve is in an out-of-park position and is vented when the valve is in a park position. In an intermediate position, a hydraulic lock condition may potentially occur. When engaging park, the hydraulic lock condition is prevented by the slidable end-cap.

Abstract: A one-way clutch includes a cam plate formed with notches, a rocker plate formed with pockets mutually spaced angularly about an axis, each pocket including an open axial end, and a surface that closes each pocket at an end opposite the open axial end of each pocket. A rocker is located in a respective pocket for movement toward and away from engagement with a notch on the cam plate. Springs are supported on the rocker plate, each spring urging a rocker toward engagement with a notch.

Abstract: A one-way clutch includes a cam plate formed with notches, a rocker plate formed with pockets mutually spaced angularly about an axis, each pocket including an open axial end, and a surface that closes each pocket at an end opposite the open axial end of each pocket. A rocker is located in a respective pocket for movement toward and away from engagement with a notch on the cam plate. Springs are supported on the rocker plate, each spring urging a rocker toward engagement with a notch.