Patent ID: 6619323
Filing Date: 2003-09-16
Classification: F16H,Y10T

Abstract:
A reverse boost valve assembly for use in combination with a pressure regulator valve installed within the hydraulic pump of an automatic transmission, said reverse boost valve assembly being disposed in fluid communication with a torque signal fluid circuit and a reverse input circuit, said reverse boost valve assembly comprising:a valve sleeve including a longitudinal bore, wherein said bore defines a valve chamber, said valve sleeve further including at least one torque signal fluid orifice formed in fluid communication with said valve chamber and the torque signal fluid circuit and at least one reverse input orifice formed in fluid communication with said valve chamber and the reverse input circuit; a valve piston disposed within said longitudinal bore, said valve piston including a plurality of control lands formed thereon, wherein said control lands are responsive to the ingress of hydraulic fluid into said valve chamber from the torque signal circuit and the reverse input circuit, said valve piston further including a hard anodize coating to produce a low coefficient of friction between the mating surfaces of said piston and said sleeve; and at least one compression spring disposed intermediate said valve piston and the pressure regulator valve, wherein said spring functions to bias said valve piston to a closed position and, in the alternative, to shift the pressure regulator valve to an open position upon the ingress of hydraulic fluid into said valve chamber thereby increasing the rate of line pressure rise.