Valve assembly

The present invention is directed to a pressure-responsive valve assembly which functions in the nature of a check valve to control fluid flow across the assembly. The assembly includes a valve body which defines first and second internal flow passages, and includes a valve seat through which at least one flow port extends for joining the first and second passages in fluid communication with each other. A flexible, resiliently deformable valve member is positioned in operative association with the valve seat, and can be deflected, in response to a sufficient pressure differential, to move out of sealing engagement with the valve seat, to thereby permit fluid flow through the valve assembly. In the preferred embodiment, the valve seat of the valve assembly defines a compound sealing surface, including first and second sealing surfaces, which cooperate with the deflectable valve member to provide enhanced resistance to reverse fluid flow, with one preferred form of the present valve assembly further including a retention projection which cooperates with the valve member to further enhance resistance to reverse fluid flow.