Seal for pipe to wall junctions

Claim 1

An improved seal for securing the junction between a pipe having an outer diameter and a walled receiving member having an opening therein, said seal being of a resilient material and of a ring-like form having inner and outer peripheries and foremost and rearmost end parts, said seal inner periphery having a radially inwardly tapered end portion at the rearmost end part of the seal, said seal including lip means at said foremost end part for abutting said receiving member at the innermost face of said lip means, said seal outer periphery at the plane of said lip means innermost face having a diameter approximating the diameter of said opening in the receiving member, said seal inner periphery extending forwardly of said lip means innermost face plane having a diameter at least approximating the outer diameter of said pipe, the improvement wherein: said seal inner periphery having a radially inwardly tapered middle portion extending in an axial direction from a plane of said lip means innermost face to said inwardly tapered end portion and constituting means providing for the stretching of said seal along said tapered middle portion in the direction of movement of said pipe during insertion of the pipe into the tapered middle portion from said seal foremost end with the seal positioned in said receiving member opening, said seal outer periphery having a radially inwardly tapered portion extending in an axial direction from said lip means innermost face plane toward said rearmost end part of the seal and constituting means providing for the stretching of said seal along said tapered middle portion during insertion of said pipe into the tapered middle portion of the seal, said tapered end portion having a diameter less than the diameter of said pipe in constituting means when expanded by the pipe for overlapping said receiving member.