Patent ID: 6089364
Filing Date: 2000-07-18
Classification: F16H,Y10T

Abstract:
A hydraulic pressure-control valve for controlling a pressure to be supplied to a frictional engaging element in an automatic vehicle transmission, including:a hydraulic pressure source;a first pressure-regulating valve connected to the hydraulic pressure source through a first passage to input an input hydraulic pressure from the hydraulic pressure source and connected to the frictional engaging element through a second passage;valve displacing means for displacing the first-pressure regulating valve at one end in a first direction such that the first pressure-regulating valve outputs a first output hydraulic pressure to the frictional engaging element in response to a command input; anda second pressure-regulating valve connected, in parallel with the first pressure-regulating valve, to the hydraulic pressure source through a third passage to input the input hydraulic pressure from the hydraulic pressure source and connected to the frictional engaging element through a fourth passage to output a second output hydraulic pressure;wherein the second pressure-regulating valve is connected to the first pressure-regulating valve to receive the first output hydraulic pressure at one end to be pressed in the first direction in such a manner that when the second pressure-regulating valve is in a first position, the second output hydraulic pressure is blocked such that the first output hydraulic pressure is output which varies by a first amount per unit of command input in response to the command input according to a characteristic, and changes in a second position in which the second output hydraulic pressure is output such that the first and second output hydraulic pressures are output which vary by a second amount.