Pipe joint

Claim 1

A pipe joint having a joint body with the inner diameter thereof larger than the outer diameter of a pipe to be joined, which comprises an annular groove formed in the inner circumference of said joint body, a spring lock-ring fitted in said annular groove, said spring lock-ring being, in contour, elliptically shaped in such a manner that the inner diameter of the minor axis is smaller than the outer diameter of the pipe, said spring lock-ring also having a split portion in its circumference, said annular groove in said joint body having from its bottom a diameter greater than the sum of double the thickness of said spring lock-ring and the outer diameter of the pipe, an annular groove formed by rolling in the outer surface of said pipe, said annular groove in said pipe being spaced a predetermined distance from the end of the pipe, said pipe having a tapered outer surface formed at its annular end, wherein, when the pipe is inserted endwise into said joint body, said spring lock-ring is caused to seat in said annular groove in the pipe and dispose the pipe in locking engagement with said joint body and a fastener loosely mounted over the outer surface of the pipe and in threading engagement with said joint body, said fastener having formed at its inside portion a tapered annular inner surface, said joint body having an annular inner shoulder radially extending from its first inside portion having an inner diameter substantially equal to the outer diameter of said pipe to its second inside portion having an inner diameter larger by a predetermined amount than the outer diameter of said pipe, whereby said annular groove is formed for receiving said spring lock-ring by said inner annular shoulder of said joint body and said tapered annular inner surface of said fastener.