PIPE COUPLINGS

• US 3,759,553 A
• Filed: 03/23/1972
• Issued: 09/18/1973
• Est. Priority Date: 04/21/1971
• Status: Expired due to Term

• Current Assignee: Raymond Charles Carter
• Original Assignee: Raymond Charles Carter
• Inventors: Carter, Raymond Charles
• Primary Examiner(s): Arola, Dave W.
• Application Number:
  US05/237,358
• Time in Patent Office: 544 Days
• Field of Search: 285/423,260,305,381
• US Class Current: 285/260
• CPC Class Codes: F16L 37/148 the securing element being flexible F16L37/144 takes precedence

Abstract

A socket and spigot pipe coupling for plastics pipes is especially adapted to withstand a pull such as is experienced in the mole-ploughing of pipe-lines into the ground by providing additional plastics material to increase the wall thicknesses to accommodate mating circumferential grooves for at least one flexible thrust rod to lock the pipes together and which rod is inserted through a hole in the socket tangential to the groove, the additional plastics material being provided by a collar secured on the outside of the socket and a sleeve secured inside the spigot which has been expanded so as to be a close sliding fit in the socket, the hole for insertion of the flexible thrust rod being provided through the collar as well as the socket.

Claims

1. A pipe coupling including mating first and second plastic pipes comprising:

a flared socket on an end of said first pipe;

a collar secured to the outside of said socket by shrink fitting, said collar providing additional material to increase the wall thickness of said socket for strength;

a plurality of circumferential socket grooves on the inside of said flared socket;

a flared spigot on an end of said second pipe, the outside diameter of said spigot being slightly less than the inside diameter of said socket, whereby said spigot slidingly mates with said socket;

a sleeve secured to the inside of said spigot by shrink fitting said spigot about said sleeve, said sleeve providing additional material to increase the wall thickness of said spigot for strength;

a plurality of first circumferential spigot grooves on the outside of said spigot, said spigot grooves positioned on said spigot to mate with said socket grooves when said spigot engages said socket, whereby a passageway is formed in the interface between said spigot and said socket, said passageway having an entrance, said entrance passing through both said collar and said socket;

a second circumferential groove at the interface between said spigot and said socket;

a sealing ring positioned in said second circumferential groove to provide sealing engagements between said pipes; and

at least one thrust rod to lock said pipes together, said thrust rod being positioned in said passageway through said entrance.

2. The pipe coupling as recited in claim 1, wherein said second circumferential spigot groove is solely on the outside of said spigot.

3. A pipe coupling as in claim 1, wherein the ultimate end of the spigot is turned over the adjacent end of the sleeve.

4. A pipe coupling as in claim 3, wherein said adjacent end of the sleeve is bevelled externally.

5. A pipe coupling as in claim 4, wherein the other end of the sleeve is similarly bevelled.