Abstract: In a driving force transmission apparatus, an oil inlet portion for introducing hydraulic fluid from one of spaces to the other one of the spaces is formed, and an apparatus case has an oil outlet portion for delivering the hydraulic fluid from the other one of the spaces to an outside of the other one of the spaces with an oil delivery capacity lower than an oil introducing capacity of the oil inlet portion. A pressure regulation valve for bringing the oil inlet portion into an open state upon reception of hydraulic pressure higher than or equal to a predetermined pressure from hydraulic fluid is arranged at the oil inlet portion.

Abstract: A hydraulic one-way clutch assembly (HOWC) is configured for use in a vehicle transmission. The HOWC assembly includes a non-rotatable disc and a rotatable disc. The non-rotatable disc extends about an axis and defines at least one exhaust port extending therethrough. The rotatable disc extends about the axis and is disposed axially adjacent the non-rotatable disc. The rotatable disc is configured to rotate relative to the non-rotatable disc, about the axis, between a closed position and an open position. The rotatable disc covers the exhaust passage when the rotatable disc is in the closed position to prevent fluid from flowing out through the at least one exhaust port. The rotatable disc uncovers the exhaust port when the rotatable disc is in the closed position to allow fluid to flow out through the at least one exhaust port.

Abstract: A torque transmitting assembly includes an actuator for engaging a torque transmitting element. A mechanism is connected to the actuator. The mechanism is operable to selectively allow fluid communication therethrough. The mechanism communicates between two separate fluid spaces located on opposite sides of the actuator. During movement of the actuator, a fluid is allowed to transfer through the mechanism between the two separate fluid spaces.