Patent ID: 6857849

Claim:
A membrane seal comprising: a) a pair of oppositely facing annular sealing grooves; and b) a first annular sealing member received in one of the oppositely facing sealing grooves and a second annular sealing member received in the other of the oppositely facing sealing grooves, the first and second sealing members being sealingly connected together by an annular membrane, the sealing members and the membrane being annular when viewed normal to the membrane, and at least one of the first and second sealing members having an oval cross-section, and the other of the first and second sealing members having a circular cross-section; c) the first and second sealing members being axially slideable within the grooves, whereby a pressure difference across the membrane forces the first and second sealing members into contact with a side wall of each of the oppositely facing sealing grooves to effect a seal.