Poppet construction for valve

In a poppet-type valve assembly having a housing provided with a bore therein, a valve stem movably supported within said bore, a plurality of ports formed in said housing and communicating with said bore at axially spaced locations, at least one of said ports communicating with said bore through an annular gap defined between first and second axially-spaced annular valve seats which are defined on said valve housing and concentrically encircle said bore, and said valve stem having a poppet-type valve member stationarily mounted therein in encircling relationship thereto, said poppet-type valve member projecting radially outwardly into said annular gap and being alternatively sealingly engageable with one or the other of said valve seats in response to shifting movement of said valve stem, said poppet-type valve member including an elastomeric poppet ring disposed in surrounding relationship to said valve stem and defining thereon a pair of axially spaced and axially oppositely facing sealing faces which are respectively engageable with said first and second valve seats, the improvement wherein said poppet ring comprises:

• each said sealing face being defined by first and second annular frusto-conical surfaces which are disposed such that said first surface is positioned radially inwardly of said second surface, said first and second surfaces intersecting one another and defining at the intersection an annular convex peak which encircles the valve stem, said peak being of a diameter which substantially equals the diameter of the respectively adjacent valve seat so that the latter contacts the sealing face substantially at the peak, said first and second surfaces each being angularly sloped in the same direction relative to the direction of shifting movement of the valve stem, and said first surface being sloped at a significantly steeper angle than the slope of said second surface.