Patent ID: 8069661

Claim:
A hydraulic control system for actuating at least one torque transmitting device in a transmission, the hydraulic control system comprising: a sump for receiving and storing a hydraulic fluid; a pump in communication with the sump, the pump having an outlet and operable to pump the hydraulic fluid from the sump to the outlet; an accumulator for storing and releasing the hydraulic fluid; a first control device having a first port, a second port, and a third port, wherein the first port of the first control device is in communication with the accumulator and the third port of the first control device is in communication with the at least one torque transmitting device, and wherein the first control device includes a valve moveable between at least two positions, wherein the first port of the first control device is in communication with the third port of the first control device when the valve of the first control device is in the first position and wherein the first port of the first control device is in communication with the second port of the first control device when the valve of the first control device is in the second position; and a second control device having a first port in communication with the outlet of the pump, a second port in communication with the second port of the first control device, and a third port in communication with the at least one torque transmitting device, wherein the second control device includes a valve moveable between at least two positions, wherein the first port of the second control device is in communication with the third port of the second control device when the valve of the second control device is in the first position and wherein the second port of the second control device is in communication with the third port of the second control device when the valve of the second control device is in the second position, and wherein the accumulator stores the hydraulic fluid when the first control device is in the first position and the second control device is in the first position and the main pump is running, and wherein the accumulator releases the hydraulic fluid when the first control device is in the second position and the second control device is in the second position.