GB2436602A

GB2436602A - Pipe coupling device for connecting a pipe to a gas valve located in a connection box

Info

Publication number: GB2436602A
Application number: GB0606085A
Authority: GB
Inventors: Christophe Caron
Original assignee: CHUCHU DECAYEUX
Current assignee: CHUCHU DECAYEUX
Priority date: 2006-03-27
Filing date: 2006-03-27
Publication date: 2007-10-03
Anticipated expiration: 2026-03-27
Also published as: GB2436602B; GB0606085D0

Abstract

A pipe coupling device for connecting a pipe 2 to a gas valve 3 in a connection box 4 comprises a coupling body 5 adapted to cooperate with a threaded clamping nut 7, a sleeve 8 received in a coupling body recess 10 and having a pipe supporting portion 12, a compression ring 18 to radially compress the pipe on said pipe support portion when the nut 7 is screwed onto the coupling body, a support ring 22 contacting an inner surface of the connection box and a friction ring 23 acting together to secure the device onto the connection box when the nut is tightened. A sealing ring 15 may be disposed between the compression ring and a skirt 13 of the sleeve. A sealing gasket 24 may also be provided between the friction ring and the outer surface of the box. The sleeve may comprise annular ribs 14.

Description

I

Pipe coupling device for connecting a pipe to a gas valve located into a connection box.

The present invention relates in general to pipe coupling devices.

The invention relates more particularly to a pipe coupling device for connecting a pipe to a gas valve located into a connection box for conveying gas for industrial or domestic use.

In such application, the gas valve generally comprises a coupling body secured on an internal surface of the connection box.

Said coupling body has a pipe support portion which projects towards the outside of the connection box to provide a support for a pipe end.

In order to securely engage the pipe end on said support portion, a metal pressure compression sleeve is coaxially arranged to surround the outer surface of the end pipe. Then, the compression sleeve is crimped onto the pipe end with a specific pressing tool.

The compression sleeve enables to inhibit removal of the pipe once mounted on the gas valve, and thus forms a pipe coupling device.

This device presents major drawbacks to require the use of a pressing tool specially designed to be able to press the compression sleeve in order to tight the pipe with the gas valve. Thus, such a pipe coupling device does not allow an easy installation.

Moreover, other potential problems exist with this type of prior art coupling device. In fact, in the case of an improper use of the pressing tool, it may occur that the pressure sleeve is not adequately fitted onto the gas valve, thereby jeopardizing the sealing of the pipe and causing possible gas leakages.

Otherwise, such a crimping does not enable to easily take apart the device, for example if the operators note that the compression sleeve is not adequately compressed on the pipe end.

Thus, an object of the present invention is to overcome the drawbacks of the aforementioned pipe coupling device.

A further object of the invention is to propose a pipe coupling device which enables to obtain an improved seal between the pipe and the gas valve, and also to achieve the immobilization of the device on the connection box.

Thus, the invention proposes a pipe coupling device for connecting a pipe to a gas valve located into a connection box, the device comprising a coupling body adapted to cooperate with a clamping nut, a sleeve received in a coupling body recess and having a pipe support portion, a compression ring to radially compress the pipe on said pipe support portion when the nut is screwed into the coupling body.

According to an aspect of the invention, the device further comprises a support ring having a contact surface with an inner surface of the connection box, and a friction ring acting together with said support ring to secure the device on the connection box when the nut is screwed into the coupling body.

With such a pipe coupling device, it thus becomes possible to obtain a precise and sure gripping engagement of the pipe end to prevent its withdrawal there from once inserted, and to simultaneously fix said device on the connection box.

In fact, the provision of a sleeve having a pipe support portion which cooperates with a deformable compression ring combined with the use of such support and friction rings enables, when the nut is screwed into the coupling body, to stress the different members disposed into the device and to fix it simultaneously on the connection box.

Such a stress of the different members into the device enables to obtain a satisfactory seal of the device. Thus, a potential gas leakages and ingress of moisture, dirt and the like into the device are limited.

Otherwise, the use of a ring and a counter-ring permits to easily fix the pipe coupling device on the connection box without additional components provided for that purpose.

According to a preferred embodiment, the device further comprise a sealing ring axially disposed between the compression ring and a radial skirt of the sleeve, said compression ring forcing the sealing ring towards the pipe when the nut is screwed so as to radially compress said sealing ring on the pipe support portion of the sleeve.

Relative rotation between the clamping nut and the coupling body axially advances the clamping nut into the recess so that an inner shoulder engages the compression ring. Said ring is thereby compressed between shoulder and the sealing ring. This axial compression, in turn, results in a radial compression of said sealing ring to improve the sealing of the device.

The device may further comprise a sealing gasket axially mounted between the support ring and the friction ring and having a contact surface with an outer surface of the connection box.

Such a sealing gasket limits ingress of moisture, dirt and the like into the connection box. Furthermore, this gasket also enables to absorb an excessive tightening of the nut. Thus, the sealing gasket performs a double function.

Preferably, the device also comprises a protection sleeve coaxially arranged around the clamping nut and forming a detection sleeve of a taking appart of the device.

Advantageously, the pipe support portion of the sleeve comprises radial ribs facing outwards for gripping engagement with an interior surface of the pipe.

The device can also comprise an additional sealing gasket axially mounted against the clamping nut, axially opposite the friction ring. Preferably, the device further comprises a cup projecting axially in part with respect to the clamping nut to support said additional sealing gasket prior to the mounting of said device on the pipe.

According to a first embodiment, the friction ring comprises a radial surface pressing against the clamping nut.

According to a second embodiment, the device further comprises a connecting bush intended to be disposed on the gas valve and a nut mounted on said connecting bush to connect the coupling body of the device with the gas valve. Preferably, the support ring is axially mounted against said nut.

In other words, the present invention concerns a pipe coupling device for connecting a pipe to a gas valve located into a connection box, comprising a coupling body adapted to cooperate with a clamping nut, a sleeve disposed into the coupling body to support the pipe, and a pressure ring which is indented to radially stress the pipe on said sleeve when the nut is screwed or clamped into the coupling body.

The device further comprises a bearing ring intended to press axially against an inner surface of the connection box, and a counter- ring acting together with said bearing ring to secure the device on the connection box when the nut is screwed into the coupling body, said counter-ring further forming a seal member.

Other advantages and features of the invention will appear on examining the detailed description of embodiments taken as examples, these being in no way limiting, and illustrated by the appended drawings, in which: -Figure 1 is a view in axial section of a pipe coupling device according to a first embodiment of the invention, -Figure 2 is a view in axial section of the device according to Figure 1 before its assembly on the pipe, -Figure 3 is an exploded view of the device according to Figure 2 schematically showing the direction of assembly of the members of the device, -Figure 4 is a view in axial section of a pipe coupling device according to a second embodiment of the invention -Figure 5 is a view in axial section of the device according to Figure 3 before its assembly on the pipe, and -Figure 6 is an exploded view of the device according to Figure 5 schematically showing the direction of assembly of the members of the device.

On Figure 1, a pipe coupling device, indicated by the general numerical reference 1, allows the mechanical tightening of a pipe 2 made of synthetic material on a gas valve 3 mounted into a connection box 4, partially illustrated.

The pipe coupling device I is particularly adapted for conveying gas for industrial or domestic use. However, it is conceived that said device can also be used for conveying other types of fluid, for instance water.

The device I includes a coupling body 5 which extends axially along its axis 6, a clamping nut 7 adapted to cooperate with said coupling body, and a sleeve 8 to support the pipe 2.

The annular coupling body 5, for example made of brass, comprises an outer axial surface having a first externally threaded portion 9a adapted to cooperate with a corresponding internally threaded portion 3a disposed at one axial free end of the gas valve 3.

The gas valve 3 also includes an externally threaded portion 3b at the other axial end to join a gas entry of the connection box 4.

The coupling body 5 also comprises a second externally threaded portion 9b, near to an axial free end of said coupling body, and adapted to cooperate with a corresponding internally threaded portion 7a of the clamping nut 7 in order to couple the clamping nut 7 by relative rotation between said members. The radial dimension of the first threaded portion 9a is markedly smaller than radial dimension of the second externally threaded portion 9b.

The coupling body 5 has a staged central bore 10 or recess that extends longitudinally over its all length and which defines a bearing surface 11 for the sleeve 8 assembled inside the coupling body 5.

The sleeve 8 may be made of brass, or of synthetic material, for instance of polyethylene, which is conform to a use with gas products. Of course, the material of sleeve 8 can be adapted according to the nature of the fluids to convey.

The annular sleeve 8 includes an axial pipe support portion 12 and a skirt 13 radially extending said support portion 12. The support portion 12 axially projects in part with respect to the second threaded portion 9b of the coupling body 5.

To cause radial interference between the sleeve 8 and the pipe 2, the support portion 12 also comprises a plurality of annular ribs 14 which extends radially outwards. The ribs 14 are capable of being into contact with the bore of the pipe 2 to maintain the end pipe with respect to the coupling body 5. In other words, the ribs 14 are tilted in order to prohibit an axial displacement of pipe 2, by butting effect.

The radial skirt 13 extends an axial free end of the pipe support portion 12 and is delimited by opposite radial surfaces 13a and 13b.

The radial surface 13a is into contact with the bearing surface 11 of the coupling body 5, the radial surface 13b forming a bearing surface for the axial end of the pipe 2.

The pipe coupling device I also comprises a seal 15, made of rubber, including a first part 1 6 having a more or less radial surface 16a pressing axially against the radial surface 13b of the radial skirt 13, and a second part 17 axially extending the first part 16 towards the clamping nut 7. The seal 15 is made in a single piece.

The first part 16 is into friction contact with said radial surface 13b and also with an annular rib 9c of the coupling body 5 disposed on the bore 10 in the vicinity of the bearing surface 11. The annular rib 9c is tilted, with regard to the axis 6, and cooperates with a corresponding surface of the seal 15.

The seal 1 5 surrounds the outer surface of the pipe 2 and axially projects in part with respect to the second threaded portion 9b of the coupling body 5. In other words, the seal 15 is radially located between the pipe 2 and the clamping nut 7. In this way, the seal 15 is capable of limiting ingress of moisture, dirt and the like into the connection box 4.

The pipe coupling device I also comprises a compression ring 18 made of synthetic material, for example of polypropylene. The ring 18 is made in a single piece. The compression ring 18 is radially located between the seal 1 5 and the clamping nut 7 and axially located between the clamping nut 7 and the second part 17 of the seal 15.

The compression ring 18 is provided with an annular heel 19 and a lip 20 which extends said heel 19, in a title way with respect to the axis 6, towards the coupling body 5 in order to come into friction contact with the outer surface of the second part 17 of the seal 15.

The heel 19 is delimited by opposite radial surfaces. One of said radial surface is into contact with the seal 15 to maintain axially said seal between the skirt 13 of the sleeve 8 and the compression ring 18, the other radial surface pressing axially in part against a bearing surface 7b of the clamping nut 7 disposed in the vicinity of the internally threaded portion 7a.

The clamping nut 7, having an annular form, radially surrounds the seal 15 and the compression ring 18. An axial free end of the clamping nut 7 is disposed near to a wall 21 of the connection box 4 and axially extending outwards.

In order to achieve the immobilization of the device 1 on the wall 21 of the connection box 4, said device I also comprises a support ring 22 and a friction ring 23, said rings being axially disposed on either side of the wall 21. The annular rings 22 and 23 are made of synthetic material, for example of (a préciser).

The support ring 22 radially surrounds the outer surface of the coupling body 5 and is axially delimited by opposite radial surfaces, one of said surface forming a contact surface with the inner surface 21a of the wall 21. The opposite radial surface is into contact with the axial free end of the gas valve 3. In this way, the support ring 22 is axially located between the gas valve 3 and the wall 21 of the connection box 4.

In a similar way, the friction ring 23 is intended to press axially against the outer surface 21b of the wall 21. To this end, a radial surface of the ring 23 is into axial contact with a bearing surface 7c disposed on the outer surface of the clamping nut 7. The opposite radial surface of said ring 23 urges against the outer surface 21b of the wall 21, via a sealing gasket 24, and makes the fixation of the device I on the connection box 4.

The sealing gasket 24 is thus axially mounted between the wall 21 and the friction ring 23, and presses axially against these members.

The sealing gasket 24 is made of synthetic material, for example of rubber. The radial dimension of the sealing gasket 24 is slightly bigger than radial dimension of the friction ring 23.

In other words, the support ring 22 and the friction ring 23 respectively constitutes a ring and a counter-ring which enable to fix the device I on the wall 21 of the connection box 4 and which also form a mechanical seal to limit the ingress of moisture, dirt and the like into the connection box 4. Besides, the disposition of the sealing gasket 24 between the wall 21 and the friction ring 23 further increases the overall effectiveness of said mechanical seal.

To this end, the device 1 is also provided with a protecting sheath 25 which radially surrounds the clamping nut 7. The protecting sheath 25, having an annular form, includes an axial portion 25a comprising, at one free end, a bearing surface pressing against the friction ring 23, axially opposite the sealing gasket 24. A radial portion 25b extends the other free end of the axial portion 25a inwards to the vicinity of the pipe 2. The protecting sheath 25 radially surrounds the clamping nut 7.

In order to limit the ingress of particles into said protecting sheath 25, the device I further comprises an additional annular sealing gasket 26, made of rubber, mounted around the pipe 2 and axially pressing against the radial portion 25b.

To carry out the fixing of the device 1 on the wall 21 of the connection box 4, initially one takes apart the clamping nut 7, the compression ring 18, the seal 15, the sleeve 8 and the sealing gasket 26. After, one mounts these members on the pipe 2 on the following order: the sealing gasket 26, the clamping nut 7, the compression ring 18 and the seal 15. Then, one mounts the pipe 2 on the sleeve 8.

The coupling body 5 threaded on the gas valve is mounted into the connection box so that the support ring 22 presses against the inner surface 21a of the wall 21.

Next, the clamping nut 7 is screwed on the coupling body 5 until the sealing gasket 24 comes into axial contact with the outer surface 21b of the wall 21. Such relative rotation between the clamping nut 7 and the coupling body 5 axially advances the clamping nut into the recess 1 0 so that the bearing surface 7b engages the compression ring 18. Said ring is thereby compressed between bearing surface 7b and the sealing ring 15. This axial compression, in turn, results in a radial compression of said sealing ring with the provision of the radial skirt of the sleeve and with the annular rib 9c of the coupling body 5.

Finally, the protecting sheath 25 is disposed around the clamping nut 7, and a protective outer glass reinforced polyester (GRP) sheath 27 is mounted around the pipe 2. The GRP sheath 27 presses axially against the protecting sheath 25. Such a GRP sheath 27 is usually disposes on such a pipe 2 in order to protect it from ultraviolet light and hence deterioration of the material of said pipe.

The GRP sheath 27 also provides protection against the ingress of dirt into the coupling device 1.

To screw off the clamping nut 7 to take apart the device 1 once the protecting sheath 25 and the GRP sheath 27 have been assembled on the pipe 2, it is necessary to prior break the protecting sheath 25.

Thus, the protecting sheath 25 forms a detection sleeve of a taking apart of the device 1.

Before its fixing on the wall 21 of the connection box 4 and before the setting of the pipe 2 on the sleeve 8, the device I also comprises, as can be seen in Figure 2, a support cup 28 to maintain the sealing gasket 26.

The support cup 28 comprises a radial portion 28a, a more or less axial portion 28b extending the radial portion 28a towards the clamping nut 7 and on which the sealing gasket 26 is disposed, and a radial skirt 28c extending outwards form said axial portion 28b.

In this way, the support cup 28 forms a retention member for sealing gasket 26 and permits to obtain a unitary device 1. The device 1 is assembled in the direction of fitment 29 as illustrated in Figure 3.

Besides, the support cup 28 also limits the ingress of dirt and the like into the device I. In the embodiment illustrated in Figure 4 in which the same reference numbers have been used for the same or corresponding parts, the device 1 is provided with an annular connecting bush 31, for example made of brass, having an externally threaded portion 3 1 a adapted to cooperate with the internally threaded portion 3a of the gas valve 3, and with an additional nut 32 disposed on the connecting bush 31 and which cooperates with an adapted coupling body 33.

The nut 32 comprises an annular flange 32a cooperating with a radial portion 3 lb of the connecting bush 3 1, which is axially opposite to the threaded portion 31a, and a fixation portion 32b axially extending said flange 32a towards the wall 21 of the connection box 4.

Said fixation portion 32b comprises an internally threaded portion 34 adapted to cooperate with a corresponding externally threaded portion 33a disposed at one axial free end of the coupling body 33.

Here, the nut 32 presses axially against a support ring 35 which comes into contact with the inner surface 21a of the wall 21 of the connection box 4.

The annular support ring 35 is made of synthetic material, for example of (a préciser). The support ring 35 is provided with an annular first part 35a axially delimited by opposite radial surfaces, one of said surface forming a contact surface with the inner surface 21 a of the wall 21, and with an annular rib 35b locally extending the first part 35a inwards to come into contact with the outer surface of the fixation portion 32b of the nut 32.

The support ring 35 also comprises, a heel 35c which radially extends the first part 35a inwards, axially opposite the rib 35b, and which also axially extends said first part 35a towards the sealing gasket 24. The support ring 35 thus comes into contact with the inner surface 21a of the wall 21 but also with the bore of said wall 21.

On the side axially opposite to the support ring 35 with regard to the waIl 21 of the connection box 4, the device 1 also comprises a friction ring 36 which is axially disposed between the sealing gasket 24 and the coupling body 33. The annular friction ring 36 is made of synthetic material, for example of (a préciser).

The friction ring 36 comprises a small diameter axial portion 36a adjusted in the bore of the sealing gasket 24, said bore being formed in the thickness of the said sealing gasket 24. A radial portion 36b extends the axial portion 36a outwards and extends in contact with a bearing surface 33b of the coupling body 33. A big diameter axial portion 36c axially extends the radial portion 36b outwards, said portion surrounding a second externally threaded portion 33c of the coupling body 33 disposed at an axial free end of said coupling body and adapted to cooperate with a corresponding internally threaded portion 38 of the clamping nut 37.

In this embodiment, the clamping nut 37, having an annular form, includes a radial portion 37a which forms a bearing surface for the heel 19 of the compression ring 18, and an axial portion 37b extending said radial portion 37a towards the friction ring 36. The axial portion 37b surrounds the compression ring 18 and the sealing ring 15, and comprises the threaded portion 38 cooperating with the threaded portion 33c of the coupling body 33.

As can be seen in Figure 5, before its fixing on the wall 21 of the connection box 4 and before the setting of the pipe 2 on the sleeve 8, this embodiment also comprises the support cup 28 to axially maintain the sealing gasket 26. In a similar way to the preceding embodiment, the device I is assembled in the direction of fitment 39 as illustrated in Figure 6.

This second embodiment is particularly adapted to a pipe 2 having an inside diameter of 32 mm, the first embodiment being adapted, for example, for an inside diameter of 20 mm.

The invention provides a pipe coupling device comprising a compressing ring which is adapted to axially and radially compress the seal ring when the nut is screwed into the coupling body in order to assure a radial compression of the pipe on the support sleeve, and a bearing ring able to cooperate with a counter-ring to simultaneously fix the device on the connection box.

The invention has been described with reference to the preferred embodiments. Obviously modifications and alterations will occur to others upon a reading and understanding of this specification.

It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

CLAIMS

1-Pipe coupling device for connecting a pipe to a gas valve located into a connection box, wherein it comprises a coupling body adapted to cooperate with a clamping nut, a sleeve received in a coupling body recess and having a pipe support portion, a compression ring to radially compress the pipe on said pipe support portion when the nut is screwed into the coupling body, a support ring having a contact surface with an inner surface of the connection box, and a friction ring acting together with said support ring to secure the device on the connection box when the nut is screwed into the coupling body.

2-Pipe coupling device according to claim 1, further comprising a sealing ring axially disposed between the compression ring and a radial skirt of the sleeve, said compression ring forcing the sealing ring towards the pipe when the nut is screwed so as to radially compress said sealing ring on the pipe support portion of the sleeve.

3-Pipe coupling device according to claim I or 2, further comprising a sealing gasket axially mounted between the support ring and the friction ring and having a contact surface with an outer surface of the connection box.

4-Pipe coupling device according to any one of claim I to 3, comprising a protection sleeve coaxially arranged around the clamping nut and forming a detection sleeve of a taking appart of the device.

5-Pipe coupling device according to any one of claim 1 to 4, wherein the pipe support portion of the sleeve comprises radial ribs (14) facing outwards for gripping engagement with a bore of the pipe.

6-Pipe coupling device according to any one of claim 1 to 5, further comprising an additional sealing gasket axially mounted against the clamping nut, axially opposite the friction ring.

7-Pipe coupling device according to claim 6, further comprising a cup projecting axially in part with respect to the clamping nut to support said additional sealing gasket prior to the mounting of said device on the pipe.

8-Pipe coupling device according to any one of claim I to 7, wherein the friction ring comprises a radial surface pressing against the clamping nut.

9-Pipe coupling device according to any one of claim 1 to 7, further comprising a connecting bush intended to be disposed on the gas valve, and a nut mounted on said connecting bush to connect the coupling body of the device with the gas valve.

10-Pipe coupling device according to claim 9, wherein the support ring is axially mounted against said nut.

11-Pipe coupling device substantially as herein described with reference to any one the accompanying drawings.