GB2133850A

GB2133850A - Pipe coupling

Info

Publication number: GB2133850A
Application number: GB08301467A
Authority: GB
Inventors: Ronald Edmondson
Original assignee: Plastiers Ltd
Current assignee: Plastiers Ltd
Priority date: 1983-01-19
Filing date: 1983-01-19
Publication date: 1984-08-01
Also published as: GB8301467D0

Abstract

A pipe coupling comprises a first member 2 inserted into the end of a pipe 1 as far as a stop 6 on the member 2. Member 2 has a rib 7, having smaller ribs 4 thereon, which deforms or cooperates with a deformation 9 in the wall of the pipe 1. A second member 3 in the form of a nut having a tapering inner surface 8 with a screw thread 5 formed thereon is screwed over the deformation 9 to clamp the pipe 1 between the first and second members 2, 3. The coupling is particularly useful for softenable plastics pipes. The first member may be symmetrical about the stop 6 to provide a straight coupling and may be shaped to form elbow joints. <IMAGE>

Description

SPECIFICATION Pipe coupling The present invention relates to a pipe coupling.

According to a first aspect of the invention there is provided a pipe coupling comprising a first member having a pipe-deforming means and a second member having a generally frusto-conical surface, the arrangement being such that in use the pipe coupling deforms a region of a pipe to be coupled therewith and clamps the deformed region between the pipe deforming means and the generally frusto-conical surface.

Preferably the first member is substantially cylindrical and adapted to be inserted in a pipe end and the pipe deforming means comprises a radially outwardly extending rib. This is particularly advantageous when using readily deformable pipes such as plastics pipes and more particularly heat softenable plastics pipes such as a polyethylene, polypropylene, polybutylene and nylon pipes.

Preferably the pipe coupling is adapted to form a fluid tight seai against a pipe wall.

Preferably the rib extends circularly around the circumference of the first member, thus facilitating the formation of e fluid tight seal between the pipe and the rib.

Preferably the second member is in the form of a sleeve or ring adapted to be located around a pipe and having a substantially frusto-conical inner surface such that the second member may be forced onto the deformed region of the pipe to clamp it. It has been found particularly advantageous to form a screw thread on said inner surface so that the second member may be screwed onto the deformed region. The circumferential rib on the first member is preferably provided with one or more small ribs to assist in retaining the coupling on the pipe, particularly when used in cooperation with a second member having a threaded frusto-conical surface.

The first and second members are preferably formed of plastics material such as acetal and are preferably each of substantially cylindrical configuration for strength.

The couplings may be provided on the ends of fittings to receive taps etc., or two or more of a said member may be formed integral with one another to form straight or curved joints or connections in pipes.

According to another aspect of the invention there is provided a method of forming a pipe joint comprising clamping a bulged region of a pipe against a member located within the pipe, thereby to retain the pipe on the member, wherein the bulged region is clamped against the member by a second member having a frusto-conical surface which is forced over said bulged region to compress it against the cooperating member.

The invention will be further described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a coupling according to the invention, fitted on a pipe end; Fig. 2 is a plan view of the coupling and pipe end of Fig. 1.

Pipe 1 is of heat softenable flexible polymer material such polyethylene, polypropylene, po!ybutylene or nylon. A first member 2 having a flange 6 is inserted in the end of the pipe 1 so that flange 6 abuts against the end of the pipe. First member 2 has a radially outwardly extending circular rib 7 therearound having small ribs 4 formed on the surface thereof. The small ribs 4 likewise extend circularly around the circumference of the rib. Rib 7 cooperates with a corresponding rib 9 formed in the pipe wall. A second member 3 is in the form of a nut having a tapering inner surface 8 having a screw thread 5 formed thereon.

To couple the coupling to the pipe end, the second member 3 is slid over the end of the pipe and the end of the pipe softened by immersion in hot water. First member 2 is inserted into the pipe end until flange 6 abuts the end of the pipe and rib 7 deforms the pipe wall to form rib 9 therein.

Second member 3 is then forced onto the rib 9, for example by screwing the nut 3 onto the rib 9, trapping the pipe between screw thread 5 and small ribs 4. A fluid tight seal is formed between small ribs 4 and the inner surface of rib 9 in the pipe wall.

Figs. 1 and 2 show the first member continued beyond flange 6, at 2a. The first member 2 may be symmetrical about flange 6 to form a straight pipe coupling or provided with a plastics or metal fitting to connect to a tap etc. Angled and 'T' connections may also be provided.

1. A pipe coupling comprising a first member having a pipe deforming means and a second member having a generally frusto-conical surface, the arrangement being such that, in use, the pipe coupling deforms a region of a pipe to be coupled therewith and the deformed region is clamped between the pipe deforming means and the generally frusto-conical surface.

2. A pipe coupling as claimed in claim 1, wherein the first member is substantially cylindrical and adapted to be inserted into a pipe end.

3. A pipe coupling as claimed in claim 2, wherein the first member has a stop to limit the extent of insertion of the members into a said pipe.

4. A pipe coupling as claimed in claim 1, 2 or 3, wherein the pipe deforming means comprises a radially outwardly extending rib.

5. A pipe coupling as claimed in claim 4, wherein the rib extends circularly around the circumference of the first member.

6. A pipe coupling as claimed in any one of claims 1 to 5, wherein the second member comprises a nut having a frusto-conical threaded inner surface.

7. A pipe coupling substantially as hereinbefore described with reference to the accompanying

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pipe coupling The present invention relates to a pipe coupling. According to a first aspect of the invention there is provided a pipe coupling comprising a first member having a pipe-deforming means and a second member having a generally frusto-conical surface, the arrangement being such that in use the pipe coupling deforms a region of a pipe to be coupled therewith and clamps the deformed region between the pipe deforming means and the generally frusto-conical surface. Preferably the first member is substantially cylindrical and adapted to be inserted in a pipe end and the pipe deforming means comprises a radially outwardly extending rib. This is particularly advantageous when using readily deformable pipes such as plastics pipes and more particularly heat softenable plastics pipes such as a polyethylene, polypropylene, polybutylene and nylon pipes. Preferably the pipe coupling is adapted to form a fluid tight seai against a pipe wall. Preferably the rib extends circularly around the circumference of the first member, thus facilitating the formation of e fluid tight seal between the pipe and the rib. Preferably the second member is in the form of a sleeve or ring adapted to be located around a pipe and having a substantially frusto-conical inner surface such that the second member may be forced onto the deformed region of the pipe to clamp it. It has been found particularly advantageous to form a screw thread on said inner surface so that the second member may be screwed onto the deformed region. The circumferential rib on the first member is preferably provided with one or more small ribs to assist in retaining the coupling on the pipe, particularly when used in cooperation with a second member having a threaded frusto-conical surface. The first and second members are preferably formed of plastics material such as acetal and are preferably each of substantially cylindrical configuration for strength. The couplings may be provided on the ends of fittings to receive taps etc., or two or more of a said member may be formed integral with one another to form straight or curved joints or connections in pipes. According to another aspect of the invention there is provided a method of forming a pipe joint comprising clamping a bulged region of a pipe against a member located within the pipe, thereby to retain the pipe on the member, wherein the bulged region is clamped against the member by a second member having a frusto-conical surface which is forced over said bulged region to compress it against the cooperating member. The invention will be further described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a coupling according to the invention, fitted on a pipe end; Fig. 2 is a plan view of the coupling and pipe end of Fig. 1. Pipe 1 is of heat softenable flexible polymer material such polyethylene, polypropylene, po!ybutylene or nylon. A first member 2 having a flange 6 is inserted in the end of the pipe 1 so that flange 6 abuts against the end of the pipe. First member 2 has a radially outwardly extending circular rib 7 therearound having small ribs 4 formed on the surface thereof. The small ribs 4 likewise extend circularly around the circumference of the rib. Rib 7 cooperates with a corresponding rib 9 formed in the pipe wall. A second member 3 is in the form of a nut having a tapering inner surface 8 having a screw thread 5 formed thereon. To couple the coupling to the pipe end, the second member 3 is slid over the end of the pipe and the end of the pipe softened by immersion in hot water. First member 2 is inserted into the pipe end until flange 6 abuts the end of the pipe and rib 7 deforms the pipe wall to form rib 9 therein. Second member 3 is then forced onto the rib 9, for example by screwing the nut 3 onto the rib 9, trapping the pipe between screw thread 5 and small ribs 4. A fluid tight seal is formed between small ribs 4 and the inner surface of rib 9 in the pipe wall. Figs. 1 and 2 show the first member continued beyond flange 6, at 2a. The first member 2 may be symmetrical about flange 6 to form a straight pipe coupling or provided with a plastics or metal fitting to connect to a tap etc. Angled and 'T' connections may also be provided. CLAIMS

7. A pipe coupling substantially as hereinbefore described with reference to the accompanying drawings.

8. A method of forming a pipe joint, comprising forming a bulge in the pipe wall and clamping the bulge between a first coupling member which cooperates with the bulge in the pipe wall and a frusto-conical surface provided on a second coupling member.

9. A method as claimed in claim 8, wherein the first coupling member has a bulge formed on an outer surface thereof and the bulge in the pipe wall is formed by inserting the first member into the pipe.

10. A method as claimed in claim 9, wherein the frost-conical surface is threaded and the second member is screwed onto the bulge in the pipe wall.

1 A method of forming a pipe joint, substantially as hereinbefore described with reference to the accompanying drawings.