GB2140887A - Pipe couplings - Google Patents

Abstract

In a pipe coupling socket 1, a stable valve member 7 is obtained by the use of spaced-apart guide arms 9 which rest on the internal peripheral wall and have projections 13 for abutting a plug 12 inserted from the other end of the socket 1. The plug 12 has an annular outer projection which outwardly urges a plurality of balls 18 annularly disposed in the socket 1. The balls 18 are returned inwardly upon abutting an internal inclined surface and fall into an annular groove 26 on the plug 12, whereby secure connection of the plug 12 and the socket 1 is achieved. <IMAGE>

Description

SPECIFICATION Pipe couplings This invention relates to pipe couplings including a socket having an axial fluid passage.

A conventional pipe coupler includes a main socket body, a plurality of tapered holes formed in the outer peripheral surface of one end of said body, a plurality of balls fitted into said holes, and a sleeve fitted over the outer peripheral surface of said socket body for axial sliding movement. According to this arrangement, a plug is inserted through the socket, so that each ball is urged axially of the socket body by engaging means formed on the inner surface of the sleeve, whereby the balls are urged into an annular groove formed in the outer peripheral surface of the plug to achieve coupling between the socket and the plug.

However, the engaging means for urging the rock balls is a flat and smooth surface similar to that of the socket body and the sleeve moves easily upon receiving a force in the thrust direction, so that the force applied to the balls attenuates to such an extent that disengagement of the plug out of the socket may take place, leading to separation therebetween, or resulting in fluid leakages which are very hazardous.

A valve member for opening or closing the fluid passage running through the socket has its front portion seated on a valve seat of a valve port. The areas of seating the valve member on the valve seat are then relatively large. To add to this, even when the working surface of the valve seat is fairly rugged, a gap is formed between the valve member and the valve seat in closing the fluid passage, thus offering a fluid leakage problem. This is because the valve member is supported in an unstable manner.

Furthermore, the unstable support of the valve member gives rise to unsatisfactory, non-uniform movement of the valve member, thus resulting in unsatisfactory opening or closing thereof.

In view of the drawbacks of the prior art pipe couplers, principal objects of the present invention are to prevent accidental separation of a plug from an associated socket, to increase pressure applied to a valve member seated on a valve seat in the socket, and to stabilize the support and movement of the valve member.

According to one aspect of this invention, I propose a pipe coupling socket including at one end ofthe socket an axially disposed inner, annular, peripheral member having one or more holes annularly disposed therein, each accommodating a ball, an outer member having an inclined inner surface adjacent the annular inner member, which surface is adapted to return the or each ball displaced from the or each hole upon an outward force being exerted thereon.

According to another aspect of the invention, I propose a connecting plug for insertion into an axial bore at one end of a pipe coupling socket, comprising an outer, peripheral wall and an inner, axial flow passage, wherein the outer surface of the outer wall has a projection and recess axially adjacent one another adjacent the insertion end of the plug, so that upon insertion of the plug into the socket, a ball seated in the socket is outwardly displaced by the projection and subsequently falls into the recess, whereby connection between the plug and the socket is achieved.

According to a third aspect of the invention, I propose a valve member for location in a flow passage in a pipe coupling socket, comprising a disc member having a diameter greater than that of a valve port in the flow passage for location on one side of the valve port against the valve seat and a plurality of spaced-apart, arcuate axial guide arms attached to the disc member, for locating on the other side of the valve port whereby the valve member is axially slidable in the flow passage.

One embodiment of the present invention is described by way of example, with reference to the drawings, in which: Figure 1 is a partly cut-away, longitudinally sectioned view of that embodiment, and Figure 2 is an enlarged perspective view of the valve member shown in Figure 1.

A socket 1 shown in Figure 1, has therein an axial fluid passage, and a rear body 2 for the socket 1 in cylindrical form includes a hose connector portion 3 on the rear side. A front body 6 in cylindrical form is fixed to the front portion of the rear body 2 through an eyelet-like valve seat 5 having a valve port 4 in the centre to form a main body of the socket 1. A valve member 7 is disposed in the rear body 2 for axial movement, and includes a disc member 8, said disc being larger in diameter than the valve port 4 at the central portion. A pair of axial guide arms 9 is symmetrically arranged on the front side of the disc 8 in such a manner that the flow of a fluid is not disturbed, said guides having a length sufficient to pass through the valve port 4. The valve member 7 has an annular collar portion 10 located on the rear side of the valve seat 5.

It is noted that each guide arm 9 is provided on the outside with an arcuate guide surface 11 which comes into sliding contact with the inner peripheral wall surface of the valve port 4, and is also provided at the front end with a projecting step 13 which is in use in engagement with the rearmost end of a plug 12. A compression spring 14 is located between the valve member and connector 3 to urge the valve member 7 and the valve seat 5 into engagement.

The socket includes a bore 15 for receiving the plug 12, which is formed through the axial portion of the front body 6, and a ball-supporting annulus 16 is located between the front body 6 and the plug 12 is inserted into the bore 15 in the front body 6 for axial sliding movement. One or more tapered holes 17 is formed in the annulus 16. One or more balls 18 project partly from the inner and outer peripheral surfaces of the annulus 16, and are seated for rolling movement in these tapered holes 17. The front body 6 is provided in the inner wall with a space 20 into which the ball 18 can roll, said space being bound by an inclined surface 19, which engages the balls 18 and directs the ball inwardly in the centripetal direction.A seal ring 21 is fitted into an inner groove in the front body 6, said ring coming into close contact with the outer peripheral surface of the plug 12 inserted into the front body 6 and serving to prevent fluid leakages. The seal ring 21 is of a Y shape in cross section as shown in Figure 1.

A hole 22 for inserting the balls 18 into the inner surface of the front body during manufacture is located in the front body 6. After the balls 18 have been inserted, a blind cap 23 is fixedly fitted into the hole 22 to prevent the balls from coming out of the same.

A sleeve 24 is fitted over the outer periphery of the front body 6 for axial sliding movement, said sleeve including an integral portion which is slidable over the inner peripheral surface of the front body 6 and receives the plug. The aforesaid ball-supporting annulus 16 is located at the plug inserting end. A compression spring 25, for biasing the sleeve 24 in the direction along which the annulus 16 is pressed by the inclined surface 19 of the front body 6, is interposed between the front body 6 and the sleeve 24, and is not exposed to view.

A groove 26 is formed in the outer peripheral surface of the plug 12, within which the balls sit.

The operation of this arrangement is as follows: The plug 12 is inserted into the opening 15 in the socket 1 so that the peripheral step of the end of the plug 12 engages the balls 18 supported by the rock ball-supporting annulus 16 of the socket 1, and the annulus 16 moves against the resilient force of the compression spring 25 to roll the ball 18 into the space 20. Further insertion of the plug 12 #causes said step to advance beyond the balls 18.When the rock ball-engaging groove 26 formed in the outer peripheral surface of the plug 12 is then in agreementwith the tapered holes 17 in the ball-supporting annalus 16, the balls 18 now located in the space 20 return within the tapered holes 17 under the action of the compression spring 25 and the inclined surface 19, and moves toward the inner peripheral surface of the annulus 16 into location in the groove 26 in the plug 12, whereby the socket 1 is coupled to the plug 12.

In some cases, external forces are applied to the socket 1 and the plug 12 in the opposite direction in this state. However, the larger those forces, the larger the aforesaid wedging action. Thus, complete coupling is achieved between the socket 1 and the plug 12 without causing disengagement of the balls 18.

Meanwhile, when the plug 12 is inserted, the rear end thereof is engaged with the step 13 formed at the end of the guide 9 to retract the valve member 7 built in the rear body 21. At this time, however, the guide surface 11 moves along the valve port 4, so that the valve member 7 disengages uniformly from the valve seat 5 to open the fluid passage. In this case, the guide 9 within the valve member 4 has its guide surface 11 slid along the inner peripheral surface of the valve port 4, so that the movement of the valve member 7 by the insertion of the plug 12 is made smooth.

In this embodiment,the seal ring 21 coming into close contact with the outer peripheral surface of the plug 12 is Y-shaped in the cross section. Thus, a larger resilient force is, on the one hand, applied to the outer peripheral surface of the plug 12, and insertion or extraction of the plug 12 is, on the other hand, facilitated with no need to use grease which has to be used with an O-ring.

Also in the embodiment a plurality of guides is symmetrically formed on the front surface of the valve member, said guides having an axial length sufficient to pass through the valve port and including arcuate guide surfaces in their outer peripheral surface. Thus, the guides for the valve member are subjected to parallel movement within the valve port to result in smooth movement of the valve member, thereby assuredly effecting opening or closing of the fluid passage.

In addition, the inclined surface is defined on the inner peripheral surface of the front body forming the main body, said inclined surface urging the ball in engagement with the groove, when the socket is coupled to the plug, and the ball-supporting annulus for supporting the rock ball is formed in unison with the sleeve. In consequence, when external forces are applied to both the socket and the plug in the opposite directions, the balls are more strongly urged in the centripetal direction under the action of the inclined surface, so that firm coupling is achieved between the socket and the plug. It is thus very unlikely that, in use, accidental separation therebetween may take place.

When the plug disengages from the socket, the annular collar portion of the valve member is seated in place at its small surface, so that the valve member is seated on the valve seat with a large pressure. Thus, even though the valve seat and/or the annular collar portion of the valve member are more or less rugged on their associated surfaces, the annular collar portion of the valve member bites into the associated surface of the valve seat for seating, with no gap, even slight, being defined therebetween so that the fluid passage is completely closed during the separation of the plug from the socket.

Claims (19)

1. A pipe coupling socket including at one end of the socket an axially disposed inner, annular, peripheral member having one or more holes annularly disposed therein, each accommodating a ball, an outer member having an inclined inner surface adjacent the annular inner member, which surface is adapted to return the or each ball displaced from the or each hole upon an outward force being exerted thereon.

2. A pipe coupling socket according to claim 1, wherein the inner annular member is axially slidable and has an integral outer portion disposed adjacent the free end of the outer member and further including biasing means between the outer portion and the outer member for urging the inner, annular member axially.

3. A pipe coupling socket according to claim 1 or 2, wherein an enclosed space is defined between the outer member and the inner member.

4. A pipe coupling socket according to claim 1,2 or 3, wherein the or each ball protrudes from both sides of the or each respective hole.

5. A pipe coupling socket according to any one of claims 1 to 4, include an inner sealing ring for engagement with a connecting plug when inserted in the socket.

6. A connecting plug for insertion into an axial bore at one end of a pipe coupling socket, comprising an outer, peripheral wall and an inner, axial flow passage, wherein the outer surface of the outer wall has a projection and recess axially adjacent one another adjacent the insertion end of the plug, so that upon insertion of the plug into the socket, a ball seated in the socket is outwardly displaced by the projection and subsequently falls into the recess, whereby connection between the plug and the socket is achieved.

7. A plug according to claim 6, wherein the projection and the recess are both annular and are associated with a plurality of balls annularly arranged in the socket.

8. A connecting plug according to claim 6 or7, inserted in a pipe coupling socket according to any one of claims 1 to 5.

9. A valve member for location in a flow passage in a pipe coupling socket, comprising a disc member having a diameter greater than that of a valve port in the flow passage for location on one side of the valve port against the valve seat and a plurality of spaced-apart, arcuate, axial guide arms attached to the disc member, for locating on the other side of the valve port whereby the valve member is axially slidable in the flow passage.

10. A valve member according to claim 9, wherein the guide arms are symmetrically disposed about the axis of the disc member.

11. A valve member according to claim 9 or 10, wherein the free ends of the guide arms have projections for abutment with the end of a plug when located in the socket.

12. A valve member according to claim 9, 10 or 11, located in the pipe coupling socket wherein the valve port is centrally defined in an eyelet-shaped valve seat in the flow passage of the pipe coupling socket.

13. Avalve member according to any one of claims 9 to 12 including means for biasing the valve and valve seat into engagement.

14. Avalve member according to any one of claims 9 to 13 incorporated in a pipe coupling socket according to any one of claims 1 to 5 or 8.

15. A socket for pipe coupling comprising in combination: an eyelet-shaped valve seat provided in the centre with a valve port, and fixed to a front end of the socket in such a manner that it is positioned in a fluid passage therein, a valve mem ber axially slidable in the fluid passage, said valve member having a diameter larger than that of the valve port at its central portion, and including at its front end an annular collar member to be seated on said valve seat and guide means which are symmetrically mounted on the front surface of said collar member, have an axial length sufficient to pass through said valve port, and include arched guide surfaces in their outer peripheries and steps at their front ends, said steps being in engagement with the end of a plug, a rock ball-supporting annulus fitted into the axial portion of said front end of the socket for axial sliding movement, said annulus being fixedly provided therearound with a sleeve, a bore axially provided in the socket extending from the front end for the insertion of said plug, a compress ion spring provided for biasing said annulus, a rock ball rollingly fitted into said annulus in such a manner that it projects partly from the inner and outer peripheral surfaces of said annulus, a zone defined by the inner wall surface of said front end, into which roll said ball and wedge-like tapered surface in engagement therewith, and a seal ring fitted towards the rear end of said bore, which comes into contact with the outer peripheral surface of said plug.

16. A pipe coupling socket according to any one of claims 1 to 5 including a connecting plug according to any one of claims 6 to 7 and a valve member according to any one of claims 9 to 13.

17. A pipe coupling socket constructed and arranged substantially as herein described with reference to Figure 1 of the drawings.

18. A connecting plug constructed and arranged substantially as herein described with reference to Figure 1 of the drawing.

19. Avalve member constructed and arranged substantially as herein described with reference to the drawing.