Patent ID: 8757047

Claim:
A fluid control device for use in a high pressure fluid system, comprising: a device body including a cavity and a high pressure circuit; a plunger positioned for reciprocal movement in said cavity; and a leakage reduction cap mounted to said plunger in such a manner said leakage reduction cap reciprocates integrally with said plunger for reducing fluid leakage flow, said leakage reduction cap including a base portion extending transversely adjacent an end surface of said plunger and a flexible portion extending from said base portion and positioned between said device body and said plunger, and defining an annular clearance gap between said leakage reduction cap and said device body, wherein said flexible portion of said leakage reduction cap resiliently flexes radially outwardly during a compression phase of the plunger in response to fluid pressure forces to reduce said annular clearance gap so as to minimize fluid leakage flow through said annular clearance gap, wherein said plunger includes a reduced diameter section and a ledge, a distal end of said flexible portion of said leakage reduction cap sealing against said ledge during operation.