Patent ID: 6907901

Claim:
A control valve for use in actuation of a hydraulic clutch comprising: a solenoid; a valve member having a valve body that is connected to and operatively associated with said solenoid, wherein said valve member has a bore disposed linearly inside said valve body so that a first end of said bore is adjacent said solenoid and a second end of said bore is located at an end of said valve body that is distal from said solenoid; a spool linearly and slidably disposed in said bore, wherein said spool portion has a first end positioned in said first end of said bore, adjacent said solenoid, and a second end positioned in said second distal end of said bore; a pressure transition region located along said spool between said first end of said second end of said spool, wherein said pressure transition region is formed by a reduced diameter area located on the surface of said spool; and a diaphragm disposed about said spool, wherein said diaphragm extends radially across said first end of said bore, wherein said diaphragm seals said solenoid from said valve body.