Blind rivet

Claim 1

A blind rivet for coupling two work pieces having aligned through-holes, being comprised of a tubular rivet with a through-hole and a set head and a mandrel having a pull shank, a thickened head which forms a snap head at the free end of the tubular rivet when the mandrel is retracted, and the pull shank of the mandrel breaks away at the preset breaking point after the formation of the snap head, one of said work pieces being adjacent the rivet set head and the other said work piece being adjacent said thickened head, the improvement comprising: said rivet being fabricated out of thermoplastic synthetic material and said mandrel having a conical part spaced from said thickened head, and a cylindrical part between said thickened head and said conical part, said conical part tapering down to a break joint with said pull shank, an integral sealing ring at the juncture of the said conical part and said cylindrical part and located between said break joint and the greatest diameter of the head, the outer diameter of said ring being greater than said conical part and said cylindrical part so that the ring projects radially all along its circumference from the conical part and the cylindrical part, the diameter of the ring being also larger than the through-hole of the tubular rivet, and the distance between the greatest diameter of the head and the sealing ring is chosen so that the sealing ring is disposed inside the through-hole of said other work piece when the rivet is set, said break joint being inside the through-hole of the rivet when it is broken whereby to have no part of the draw shank extending from the rivet after the rivet is set and the draw shank broken off.