Demand responsive flow control valve

In a demand responsive flow control valve in a fluid conduit between a pump and a motor vehicle power steering gear including

• a housing having a passage therein defining a portion of said fluid conduit,
• a flow control orifice in said passage dividing said fluid conduit into an upstream segment connected to said pump and a downstream segment connected to said steering gear,
• a valve pintle mounted on said housing for linear translation toward said flow control orifice to an active position obstructing said flow control orifice and reducing the effective area thereof to reduce the fluid flow rate in said downstream segment of said fluid conduit to a predetermined low flow, and
• a stop means on said housing defining an inboard stop operative to terminate linear translation of said valve pintle toward said flow control orifice at said active position thereof,
• the improvement comprising:
• an interference fit between said stop means and said housing frictionally coupling said stop means to said housing in an initial position of said stop means wherein said inboard stop thereon terminates linear translation of said valve pintle toward said flow control orifice before said valve pintle attains said active position thereof, and
• a drive means operative from outside of said housing during fluid flow through said fluid conduit at a rate exceeding said predetermined low flow to calibrate the position of said inboard stop by thrusting said valve pintle against said inboard stop with a force exceeding said frictional couple between said stop means and said housing and by thereafter inducing linear translation of said stop means as a unit with said valve pintle from said initial position of said stop means toward said flow control orifice until said valve pintle obstructs said flow control orifice and reduces said fluid flow rate in said downstream segment of said fluid conduit to said predetermined low flow.