Patent ID: 7125054
Filing Date: 2006-10-24
Classification: F16L,Y10S

Abstract:
1. A self-restrained pressure gasket for insertion within a circumferential recess provided in a bell end opening of a first iron pipe capable of both joining and sealing the first pipe to a mating male plastic pipe having an interior surface and an exterior surface to create a sealed pipe joint, the gasket comprising: an annular gasket body made of a resilient elastomeric material, the annular gasket body having an inner circumferential region and an outer circumferential region, the inner circumferential region having a circumferential recess located therein; a relatively rigid ring located on the inner circumferential region of the gasket body within the circumferential recess of the gasket body, the ring having an inner circumferential surface, an outer circumferential surface and one opening at one circumferential location which creates one overall gap between opposing faces of the ring of a predetermined distance between the opposing faces when the gasket is in a relaxed state; at least one row of gripping teeth located on the inner circumferential surface of the relatively rigid ring for engaging selected points on the exterior surface of the mating male plastic pipe; wherein the overall gap between the opposing faces of the relatively rigid ring is at least partly filled with a mass of rubber having opposite end regions which form a rubber partition between the opposing faces of the ring and wherein the opposing faces of the relatively rigid ring are spaced apart from at least one of the rubber end regions by a secondary gap in a relaxed state prior to assembly of the pipe joint; and wherein the overall gap in the ring closes by a predetermined amount as the pipe joint is assembled, the distance between the opposing faces of the ring being selected to prevent the gripping teeth from engaging the exterior surface of the male plastic pipe prematurely before the gasket has been compressed enough to create a seal.