GB1595172A

GB1595172A - Pipe couplings

Info

Publication number: GB1595172A
Application number: GB5318276A
Authority: GB
Original assignee: Wavin BV
Current assignee: Wavin BV
Priority date: 1977-12-19
Filing date: 1977-12-19
Publication date: 1981-08-12

Description

(54) IMPROVEMENTS IN OR RELATING TO PIPE COUPLINGS (71) We, WAVIN B.V., a Dutch corporate body of Handellaan 251, Zwolle, Holland, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: This invention relates to pipe coupling.

In our Patent Specification No. 1,418,645, to which reference is directed, we disclose a pipe socket assembly comprising a socket, and an end cap fitted on the outside of the socket to form a recess with the socket accommodating a retaining portion of a sealing member, wherein the fit of the end cap on the socket is such as to permit axial movement of the end cap thereon from its normal position in response to an axial force and to cause return of the end cap to its normal position on removal of said forces.

We have now devised an improvement in or modification of such an assembly.

The present invention provides a socket assembly comprising a socket, and an end cap fitted on the outside of the socket to form a recess with the socket accommodating a portion of a sealing member, wherein the fit of the end cap on the socket is such as to permit axial movement of the end cap thereon from its normal position in response to an axial force and to cause return of the end cap to its normal position on removal of said force, and wherein an annular projection extends radially outwardly from the socket adjacent to an axially inner end of the end cap for protecting the end cap against an axially outwardly directed force, tending to push the end cap off the socket, being applied to said axially inner end.

In order that the invention may be well understood, two embodiments thereof, which are given by way of example only, will now be described reference being had to the accompanying drawings, in which: Figure 1 is a semi-axial cross-section of a socket assembly; and Figure 2 is a semi-axial cross-section of another socket assembly having a spigot received therein.

Referring to Figure 1, there is shown a socket assembly comprising a socket 1 for receiving a spigot (not shown in Figure 1) the degree of insertion of which is limited by an internal abutment shoulder (not shown), an end cap 2 fitted on the outside of the socket 1, and a resilient sealing member 3 for providing a seal against an inserted spigot. The end cap defines a radially inwardly opening recess with the rim 4 of the socket which accommodates a retaining portion 5 of the sealing member, which portion 5 is clamped between the rim 4 and the opposed surface 6 of the end cap. The end cap has a radially inner portion which extends axially inwardly to define the opening of the recess. A conical sealing portion 7 of the sealing member extends radially inwardly of the opening of the recess and engages when a spigot is inserted into the socket assembly both the external surface of the spigot, by means of projections 8, and the internal surface 9 of the end portion of the socket, which is of an enlarged diameter, by means of projections 10.

The end cap 2 comprises a resilient synthetic plastics material and its radially outer, axially extending portion is snap-fitted onto the outside of the socket which is also of a plastics material, by means of co-operable formations 11 and 12 thereon which allow the end cap to move axially on the socket in response to forces arising, for example, from a generally axially inwardly directed impact on the axially outer end 13 of the assembly.

As illustrated, the formations 11 and 12 are of a wave-like character similar to those described in the aforementioned specification which causes a camming action between cooperating flanks on relative axial movement between the end cap and the socket for returning the end cap to its original, or normal, position when the axial force is removed. The resilient nature of the retaining portion 5 of the sealing member assists such a return of the end cap. An annular projection 14 extends radially outwardly from the socket adjacent to the axially inner end 15 of the end cap for protecting the end cap against an axially outwardly directed force tending to push the end cap off the socket, being applied to the end 15.

The projection 14 is spaced from the end 15 to allow axially inward movement of the end cap on the socket and as shown has an outer diameter substantially equal to the outer diameter of the end 15.

Advantageously, the provision of the protecting projection 14 enables the end 15 of the end cap to be provided with a planar, substantially radial face which greatly assists injection moulding of the end cap by providing a suitable surface thereon which can be engaged for pushing the end cap off its mould.

The projection 14 can also be formed, as illustrated, so as to provide with its axially inner side 16 a should forming a mounting bracket location.

Figure 2 shows an alternative socket assembly with a spigot 17 received therein like parts have been given like reference numerals in the Figures.

The socket assembly in Figure 2 primarily differs from the assembly in Figure 1, in that whereas axial dimension of the recess for accommodating the seal retaining portion 5 and of the portion 5 increases radially outwardly of the opening of the recess in each of the assemblies to prevent the retaining portion being pulled through the opening and the sealing member thereby being dislodged from the assembly when a spigot is inserted therein, the increase is more marked in the assembly of Figure 2, where both the rim 4 and the opposing surface 18 of the end cap are inclined substantially the same amount with respect to the axis of the socket assembly and the retaining portion 5 has a generally trapizoidal crosssection.

The assembly shown in Figure 2 is also provided with an alternative form of sealing member which is formed with a connecting portion 19 interconnecting the retaining portion 5 and the sealing portion 7, which connecting portion 19 has the same thickness throughout its length. Alternatively the thickness of the portion 19 could reduce as it approached the sealing portion. Further details and advantages of the sealing member shown in Figure 2 are mentioned in our co-pending application No.

34494/76 (Serial No. 1595171) to which reference should be made.

WHAT WE CLAIM IS: 1. A socket assembly comprising a socket, and an end cap fitted on the outside of the socket to form a recess with the socket accommodating a portion of a sealing member, wherein the fit of the end cap on the socket is such as to permit axial movement of the end cap thereon from its normal position in response to an axial force and to cause return of the end cap to its normal position on removal of said force, and wherein an annular projection extends radially outwardly from the socket adjacent to an axially inner end of the end cap for protecting the end cap against an axially outwardly directed force, tending to push the end cap off the socket, being applied to said axially inner end.

2. A socket assembly as claimed in claim 1, wherein said end cap comprises radially inner and outer, axially extending portions, said radially outer portion being fitted to said outside of the socket, and said radially inner portion extending axially inwardly to define an opening of said recess with said socket.

3. A socket assembly as claimed in claim 2, wherein the axial dimension of the portion of the sealing member accommodated in the recess increases radially outwardly of said opening.

4. A socket assembly as claimed in any one of the preceding claims, wherein said axially inner end of the end cap comprises a planar, substantially radial face.

5. A socket assembly as claimed in claim 4, wherein the outer diameter of said end face is substantially equal to the outer diameter of said projection.

6. A socket assembly as claimed in any one of the preceding claims, wherein the axially inner side of said projection is formed such as to provide a mounting bracket location.

7. A socket assembly substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.

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Claims

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

of the end 15.

Advantageously, the provision of the protecting projection 14 enables the end 15 of the end cap to be provided with a planar, substantially radial face which greatly assists injection moulding of the end cap by providing a suitable surface thereon which can be engaged for pushing the end cap off its mould.

The projection 14 can also be formed, as illustrated, so as to provide with its axially inner side 16 a should forming a mounting bracket location.

Figure 2 shows an alternative socket assembly with a spigot 17 received therein like parts have been given like reference numerals in the Figures.

The socket assembly in Figure 2 primarily differs from the assembly in Figure 1, in that whereas axial dimension of the recess for accommodating the seal retaining portion 5 and of the portion 5 increases radially outwardly of the opening of the recess in each of the assemblies to prevent the retaining portion being pulled through the opening and the sealing member thereby being dislodged from the assembly when a spigot is inserted therein, the increase is more marked in the assembly of Figure 2, where both the rim 4 and the opposing surface 18 of the end cap are inclined substantially the same amount with respect to the axis of the socket assembly and the retaining portion 5 has a generally trapizoidal crosssection.

The assembly shown in Figure 2 is also provided with an alternative form of sealing member which is formed with a connecting portion 19 interconnecting the retaining portion 5 and the sealing portion 7, which connecting portion 19 has the same thickness throughout its length. Alternatively the thickness of the portion 19 could reduce as it approached the sealing portion. Further details and advantages of the sealing member shown in Figure 2 are mentioned in our co-pending application No.

34494/76 (Serial No. 1595171) to which reference should be made.

WHAT WE CLAIM IS: 1. A socket assembly comprising a socket, and an end cap fitted on the outside of the socket to form a recess with the socket accommodating a portion of a sealing member, wherein the fit of the end cap on the socket is such as to permit axial movement of the end cap thereon from its normal position in response to an axial force and to cause return of the end cap to its normal position on removal of said force, and wherein an annular projection extends radially outwardly from the socket adjacent to an axially inner end of the end cap for protecting the end cap against an axially outwardly directed force, tending to push the end cap off the socket, being applied to said axially inner end.
2. A socket assembly as claimed in claim 1, wherein said end cap comprises radially inner and outer, axially extending portions, said radially outer portion being fitted to said outside of the socket, and said radially inner portion extending axially inwardly to define an opening of said recess with said socket.
3. A socket assembly as claimed in claim 2, wherein the axial dimension of the portion of the sealing member accommodated in the recess increases radially outwardly of said opening.
4. A socket assembly as claimed in any one of the preceding claims, wherein said axially inner end of the end cap comprises a planar, substantially radial face.
5. A socket assembly as claimed in claim 4, wherein the outer diameter of said end face is substantially equal to the outer diameter of said projection.
6. A socket assembly as claimed in any one of the preceding claims, wherein the axially inner side of said projection is formed such as to provide a mounting bracket location.
7. A socket assembly substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.