Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
233 words
A pipe coupling including substantially rigid socketed and spigoted plastic pipes of substantially constant and equal wall thickness and nominal diameter, the socket and the inserted spigot integrally pre-formed in the pipe with a sealing ring therebetween and comprising: a first portion of the spigot spaced from its ultimate end expanded so as to be a close sliding fit in the socket, said socket being expanded to receive said first portion so that no reduction of the nominal diameter of said pipes including the coupling is necessary, a second portion of the spigot between the expanded portion and the ultimate end of the spigot, said second portion being substantially the same nominal diameter as said pipes, said sealing ring being located on said second portion and cooperating with said expanded socket, a third and expanded portion of the spigot still farther from the ultimate end of the spigot than said second portion, the two expanded portions forming between them a circumferential indentation round the outside of the spigot, said indentation being substantially the same nominal diameter as said pipes, a portion of the expanded socket being expanded still further to form a circumferential groove round the inside of the socket mating with said indentation on the spigot and a flexible locking rod inserted through a hole in the socket tangential to the mated indentation and groove to lock the coupling against axial separation.
Claim 2
Dependent Claim
233 words
A pipe coupling including substantially rigid socketed and spigoted plastic pipes of substantially constant and equal wall thickness and nominal diameter, the socket and the inserted spigot integrally pre-formed in the pipe with a sealing ring therebetween and comprising: a first portion of the spigot spaced from its ultimate end expanded so as to be a close sliding fit in the socket, said socket being expanded to receive said first portion so that no reduction of the nominal diameter of said pipes including the coupling is necessary, a second portion of the spigot between the expanded portion and the ultimate end of the spigot, said second portion being substantially the same nominal diameter as said pipes, said sealing ring being located on said second portion and cooperating with said expanded socket, a third and expanded portion of the spigot still farther from the ultimate end of the spigot than said second portion, the two expanded portions forming between them a circumferential indentation round the outside of the spigot, said indentation being substantially the same nominal diameter as said pipes, a portion of the expanded socket being expanded still further to form a circumferential groove round the inside of the socket mating with said indentation on the spigot and a flexible locking rod inserted through a hole in the socket tangential to the mated indentation and groove to lock the coupling against axial separation.
Claim 3
Dependent Claim
31 words
A pipe coupling as in claim 1, wherein the socket is encircled by a reinforcing collar, said collar having an enlarged portion to accommodate the groove forming expansion of said socket.
Claim 4
Dependent Claim
34 words
A pipe coupling as in claim 1, wherein the first and third expanded portions of the spigot are provided with internal reinforcing sleeves, said sleeves being substantially the same nominal diameter as said pipes.
Claim 5
Dependent Claim
32 words
A pipe coupling as in claim 3, wherein the sleeves for said first and third expanded portions of the spigot are provided with an annular connection to resist deformation of the spigot.