Patent ID: 7059638

Claim:
A self-fastening tap for connecting a branch pipe to an aperture of a given diameter provided in a main pipe, said tap comprising: a hollow cylindrical body having a first open end of a given diameter and a second open end opposed to the first open end, said cylindrical body being sized to fit and seal the aperture provided in the main pipe, the first open end having an outer side provided with a flexible lip and an inner side provided with abutment means for abutting the branch pipe, the flexible lip having an outer diameter larger than the diameter of the first open end of the cylindrical body, the second open end having an outer side provided with an outer rim, and the cylindrical body having an inner wall provided with a peripheral recess forming a vacuum chamber around the branch pipe when said branch pipe is inserted in the tap; and at least one removable spacing ring slideably mounted around the cylindrical body between the flexible lip and the outer rim.