Patent ID: 8038176

Claim:
A seal for a pipe coupling having a plurality of segments attached in end to end relation surrounding a central space, said seal being positionable within said central space and comprising: a first ring formed of a flexible, resilient material, said first ring having first and second oppositely disposed side portions extending circumferentially, and a center portion positioned between and connecting said side portions to one another, each of said side portions having an outer diameter greater than the outer diameter of said center portion; a circumferential groove positioned within said center portion and facing radially inwardly; a first sealing surface positioned on said first side portion and facing radially inwardly; a first pressure channel positioned between said first side portion and said circumferential groove; a first pressure actuated surface positioned on said first side portion opposite to said first sealing surface and facing said first pressure channel; a second sealing surface positioned on said second side portion and facing radially inwardly; a second pressure channel positioned between said second side portion and said circumferential groove; a second pressure actuated surface positioned on said second side portion opposite to said second sealing surface and facing said second pressure channel; a second ring having an outer portion positioned within said circumferential groove and an inner portion projecting radially inwardly, said second ring having an outer diameter less than an inner diameter of said circumferential groove so as to leave a gap between said first and second rings within said circumferential groove.