Spool valve device

Claim 1

A valve assembly comprising, a body having a front end and a rear end and a generally cylindrical, lengthwise extending bore with a plurality of ports communicating with said bore, slide valve means mounted oN said body being disposed for movement within said bore and adapted to selectively interconnect certain of said ports, said slide valve means includes a support member disposed for reciprocal movement within said bore, said support member comprising an elongated rod having its lengthwise axis extending in the axial direction of said bore and including an outer end adapted to be disposed outwardly of said bore adjacent said front end and an inner end adapted to be disposed interiorly of said bore, a one-piece spool member made from a resilient, compressible material mounted on the inner end of said rod being disposed interiorly of said bore for movement by said rod between a closed position and an open position, said spool member is of a generally cylindrical construction including generally flat end walls, said rod having a shoulder disposed axially inward from the distal end of its inner end abuttingly engaging said spool member, said spool member being disposed in encompassing relation about the inner end of said rod having one end wall disposed in abutting engagement with said shoulder, said spool member having a substantially uniform transverse dimension throughout its length and outer peripheral surface disposed for pressured sliding engagement with the confronting interior surfaces of said bore for closing-off selective of said ports, selectively adjustable compression means mounted on said rod on the side of said spool member remote from said shoulder for compressing said spool member in the axial direction of said rod against said shoulder for radially expanding said spool member into pressured sealing contact with the interior surfaces of said bore, valve seat means mounted on said body adjacent said front end, said valve seat means including a packing member made of a resilient compressible material, said body includes an annular bore shoulder disposed within said bore adjacent the front end thereof, said packing member is of a generally cylindrical configuration and is disposed within said bore including an inner face disposed in abutting engagement with said bore shoulder and extending into said bore, said packing member including a central bore for slidably receiving said rod therethrough, a seat member is threadably connected to said body adjacent said front end for compressing said packing member in a radial and axial direction into pressured sealing engagement with said shoulder and said rod for sealing off said one end of said body, and said spool member is disposed at the end on said bore adjacent said packing member in the closed position of said valve assembly to relieve the pressure on said packing member and prevent leakage through said valve seat means.