PRESSURE MODULATING AND REDUCING VALVE

摘要

Pressure Modulating and Reducing Valve A pressure modulating and reducing valve communicates pressurized hydraulic fluid from a pump to a hydraulically actuated clutch of a transmission at a modulated rate of pressure rise and at a reduced pressure. In order to provide a compact valve, the valve has a pressure reducing valve spool slidably nested within a sleeve member of a load piston to provide a valving action therebetween for controlling fluid flow between an inlet port, a load port and a drain port in a body. Movement of the sleeve member causes an increase in the pressure at the load port which causes the pressure reducing valve spool to move against a spring to establish a pressure in the load port proportional to the travel distance of the sleeve member. Movement of the sleeve member is controlled by a solenoid control valve having a spool slidably nested within a projection of an end wall extending into a bore of the pressure reducing valve spool.