GB2036224A

GB2036224A - Improvement to connectors for flexible or semi-flexible tubes or pipes

Info

Publication number: GB2036224A
Application number: GB7940412A
Authority: GB
Original assignee: Legris SA
Current assignee: Legris SA
Priority date: 1978-11-24
Filing date: 1979-11-22
Publication date: 1980-06-25
Also published as: FR2442394A1; GB2036224B; DE7933147U1; FR2442394B1; ES486307A1

Abstract

A connector for flexible or semi- flexible tubes or pipes, comprises a body 3a with an internal housing 3e receiving internally a flexible clamp 8 provided with a plurality of jaws 8a adapted to engage the wall of the tube 2 to be connected. A tubular member 9, secured onto the body 3a holds the different elements in position inside the body, said tubular member being provided with a cylindrical internal housing 9a, in which a pusher 11 is mounted for axial sliding, the path of which pusher is limited by a safety clip 12c provided at one end of the tubular member 9, said pusher being adapted to come into contact with the clamp 8 in order to release same after removal of the clip 12c. <IMAGE>

Description

SPECIFICATION Improvement to connectors for flexible or semi-flexible tubes or pipes.

The present invention relates to an improve ment to connectors for flexible and semiflexible tubes or pipes.

The tubes or pipes in question are straight but subjected to important lateral movements, or they are spiral pipes known in industry for their flexibility which allows them to be extended over a great length from a compact assembly. These spiral pipes, or tubes used for the distribution of compressed air, allow horizontal movements to supply apparatus working by compressed air, such as pneumatic drills, screwdrivers, etc.

Said pipes or tubes, which, when in use, are very strongly pulled at their ends in particular, are generally supported at those ends by a steel spring inserted in the connector in which the said pipe is fitted and which, during the flexing movements, supports the plastic over a length varying between 5 and 20 cm depending on the diameter.

It is absolutely essential for these tubes to be supported where they are secured to the connector in order to last longer, on account of the risk of quick breaking existing at their point of insertion in the connector. For this reason, it is impossible to avoid using the support spring inserted in the connector.

Despite all these precautions, the tubes need to be frequently replaced, before they become dangerous for people to use. There is then the problem of assembly and disconnection of these pipes, and it is precisely the aim of the present invention to solve this problem.

The present invention proposes a possibility of instant assembly and disconnection of such pipes, despite the presence of the spring.

From U.S. Patent No. 3653689, of the Applicant, a quick-releasable connector is known which it is the aim of the present invention to improve. Additional improvements have been made to said patent U.S.

patents Nos. 3999783 and 3 909 046. Patent No. 3909046 describes in Fig. 14 an embodiment of instant connector wherein the guide spring is firmly fitted in the instant connector and wherein it is possible to fit the bare and cylindrical plastic tube, directly and instantly in the connector. But, on the other hand, it is impossible to disconnect the tube without unscrewing the nut which is used as a casing for the connector assembly.

According to the invention, the connector comprises a tubular member, fast with the body by one of its ends, and holding the different elements in position inside the body, said tubular member being provided at its other end with a cylindrical internal housing, in which a pusher is mounted for axial sliding, the path of which pusher is limited by a stop means provided at one end of the tubular member, said pusher being adapted to come into contact with the clamp in order to actuate same and release the tube when a locking member provided between the pusher and the tubular member is dismounted.

The aim of this particular arrangement is to facilitate the disconnection of the pipe, despite the presence of the guide spring. Then the replacement and maintenance of the pipe and the spiral connector become routine work and easier.

Other characteristic features of the invention will emerge from the following description and from the accompanying drawings in which: Figure 1 is an overall view of an installation comprising a connector according to the invention, Figure 2 is a perspective view of the spiral tube provided at its ends with connectors, Figure 3 is a half-view of a longitudinal section of one embodiment of the improved connector according to the invention, Figure 4 is a half-view of a longitudinal section of another embodiment of the connector according to the invention, Figure 5 is a half-view of a longitudinal section of another embodiment of the connector according to the invention, Figure 6 is a half-view of a longitudinal section of another embodiment of the connector according to the invention, Figure 7 is a half-view of a longitudinal section of a connector with no guide spring.

Fig. 1 shows a carriage 6 mounted on a cable 5 fixed at its two ends on two supporting members. Said carriage 6, moving along said cable, is supplied with compressed air by a tube 13 connected to the carriage by a spiral tube 2, as shown in Fig. 2, and allowing the carriage to move over the whole length of the cable.

At the lower part of the said carriage is mounted a spiral tube 4 leading down as far as the ground, to supply movable pneumatic machines (such as pneumatic drills and screwdrivers), only a part of said tube 4 being shown in said drawing.

As illustrated by Figs. 1 and 2, the tubes 2 and 4 are provided at their ends with connectors 3 followed by support springs 12.

For this reason, the plastic spiral tube is subjected to considerable stresses at its point of insertion into the connectors 3.

Fig. 3 shows one embodiment of a connector 3 according to the invention, consisting of a body 3a in which is mounted an assembly of a known type comprising an O-ring 6 situated in a housing 3d, a guide washer 7 and a socket 10 both situated in a housing 3e, said socket 10, which presents a divergent area or cone 10a, receiving a clamp 8 for clamping the tube 2.

The plastic tube 2 engages, at its end, a recess 3c of the body, the O-ring 6, the washer 7 and the jaws 8a of the clamp 8.

The socket loins held in position, together with the connector assembly, by a nut 9 which is screwed on an external threading 3b provided on the body 3a Said nut 9 is extended by a tail defining a cylinder-shaped internal housing 9 a, inside which a pusher 11 is mounted for axial sliding, the axial path of which is limited by the crimped edge 9 b of the nut, engaged in a groove 11 b of the pusher, so that said latter permits to push back the tail of the clamp 8 and to release the jaws 8a engaged in the wall of the tube 2, to disconnect the latter from the connector by pulling.

A safety clip 1 2c is provided in the groove 11 b for the purpose of preventing any untimely axial movement of the pusher 11. The said clip I2cconsists of a split springy ring and can be provided with a catch tug for easy gripping.

The pusher 11 is provided with a cylindrical part 11 a constituting a guiding area for the tube 2 and with an internal threading 11 e showing semi-circular threads into which is screwed one of the ends of a spring 12 fitted around the tube 2 and extending over a limited portion of the said tube. At its free end, the spring 12 is provided with two or three close together coils 1 2b which give the said end a good appearance and a good strength.

In order to avoid any loosening and disconnecting of the spring 12 inside the pusher, the latter is provided with a crimped edge 11 dturned down over one of the coils of the spring, so that said spring 12 is integral with the pusher 11.

The connector being thus assembled as described hereinabove, the tube 2 may be mounted instantly without the clip 12 having to be released from its safety position.

To disconnect the tube, on the contrary, it is necessary to release the clip 1 2 c from the groove 11 b, an operation which is extremely easy.

The clip 12 having been removed, a simple pressure exercised on the face 1 1 c of the pusher 11 will suffice to cause the latter to push back the clamp 8 and to release it from the divergent area or locking cone 1 Oa, thereby permitting the release of the tube without any problem. The safety clip 1 2c should be replaced as soon as the tube is released. To fit in a new spiral tube, said tube needs only to be pushed inside the connector without any special precaution.

The path X (Fig. 3) provided between the tail of the clamp 8 and the face of the pusher 11 which is perpendicular to the sliding axis corresponds to a safety stop of the said clamp under the pulling forces and the pressure exerted on the tube. This is one of the main characteristics of the mobile pusher 11 which is used as safety stop for the clamp 8. Said safety path X of the clamp makes it possible to limit the clamping action of the latter and to prevent it from excessively clamping the plastic tube.

Fig. 4 shows another embodiment of the connector comprising a body 3a provided with a tapped hole 3b inside which is screwed a hollow screw 14 comprising the divergent area or cone 1 4a locking the clamp 8. Said hollow screw holds the washer 7 in position in its housing 3e and the O-ring 6 in position in its housing 3d.

Said hollow screw comprises a cylindrical recess 1 4b which allows the limited axial movement of the pusher 11 as indicated above.

The fitting of the spring 12 is also different from what is shown in Fig. 3.

In the pusher 11 is provided a bore 11 g inside which engages the spring 12 and which is extended by a groove receiving a coil 1 2a of the spring with a larger diameter than that of the other coils and which is wedged and secured inside the pusher 11 by way of a washer 16 provided with a cylindrical bore 16 a defining a shoulder means to support the said coil 12a.

The washer 16 is made integral with the pusher 11 by means of a crimped edge 11 for said pusher. Such an arrangement permits the complete locking of the spring 12 which becomes absolutely impossible to disconnect and really integral with the pusher 11.

Fig. 5 shows a variant of the embodiment shown in Fig. 4 wherein the connector is fitted on the body without any threading.

The body 3a is provided with a bore 3e receiving a tubular member 15 held in position inside the body by means of a crimped edge 3fof said body engaged in a peripheral groove provided in the tubular member 15.

Said tubular member 15 comprises a divergent area or cone 1 5a which is used for locking the clamp 8 in position. Said tubular member 15 holds the guide washer 7 in position inside its housing 3e and the O-ring 6 in position inside its housing 3b. Said tubular member 15 comprises a cylindrical recess 1 5b in which the holder 11 can slide axially. The fitting of the spring on the pusher is identical to that shown in Fig. 4.

Fig. 6 shows a variant of the embodiment shown in Fig. 3, wherein a nut 9, screwed on the body, supports the pusher 11. Concerning the fitting of the spring 12 on the pusher 11, this is done by means of a supported washer 16, ensuring the locking in position of one of the spring coils as shown in Figs. 4 and 5.

Fig. 7 shows an embodiment of connector which is a variant of the embodiment shown in Fig. 5 and wherein a sealing ring 17 of the O-ring type, is placed between the pusher 11 and the tail of the clamp 8, so as to ensure tightness between the hollow part 15 and the tube. A fixed ring is placed against the pusher 11 to serve as a stop means. In order to be held in position on one side against the pusher 11, the seal 17 is supported on the other side by a washer 18 which is subjected to the action of a helical spring 19 resting against the base 1 5b of the hollow part 15.

This arrangement makes it possible to compress the seal 17 between the washer 18 and the pusher 11, under the effect of the liquid pressure, and over an area of the tube which cannot be erased by the jaws 8a of the clamp 8. The result of this is an improvement in the tightness to all pressures in smooth or grooved pipes.

It is of course possible, if necessary, to provide the pusher 11 with a guide spring 12 as in the other embodiments. And furthermore, a groove 20 is provided between the body 3a and the hollow part 15 at the level of the crimped part 3b.

Various modifications may of course be made by those skilled in the art to the devices described hereinabove by way of example and non-restrictively, without departing from the scope of the invention. For example, the system for locking the part 11 in position by means of the crimped edges 9b in Figs. 3, 14cin Fig. 4, 15coin Fig. 5 and 9bin Fig. 6, may be replaced by those skilled in the art by another locking system preventing the pusher from coming out of the pieces 9, 14, 15 respectively.

There are large possibilities of industrial applications opened to the invention, such as a very mobile distribution of compressed air in factories, the distribution of compressed air to breaking systems in trucks and trailers-now- adays trucks are nearly all equipped with this type of plastic spiral tube, the distribution of various fluids such as gases, or water to mobile stations, for washing or painting for example.

Claims

1. An improvement to instant connectors for flexible or semi-flexible tubes, comprising a body with an internal housing receiving internally a flexible clamp with a plurality of jaws adapted to engage the wall of the tube to be connected, the said housing comprising a divergent area placed on the inner side of the connector to clamp the jaws of the clamp, an O-ring held in position by a washer ensuring tightness between the tube and the connector, said improved connector comprising a tubular member, fast with the body by one of its ends, and holding the different elements in position inside the body, said tubular member being provided at its other end with a cylindrical internal housing, in which a pusher is mounted for axial sliding, the path of which pusher is limited by a stop means provided at one end of the tubular member, said pusher being adapted to come into contact with the clamp in order to actuate same and release the tube when a locking member provided between the pusher and the tubular member is dismounted.

2. An improvement as claimed in claim 1, wherein the pusher is provided with a central bore inside which is firmly fitted a spring for guiding and supporting the tube, said spring, which is placed around said tube, extending on the outside of the connector over a predetermined distance.

3. An improvement as claimed in claim 1 or 2, wherein the tubular member constituting the cylindrical housing for the disconnection pusher is screwed on the external wall of the body and constitutes a stop means for a socket having the divergent area, the said tubular member holding the washer and the sealing ring in position.

4. An improvement as claimed in claim 1 or 2, wherein the tubular member constituting the cylindrical housing for the disconnection pusher is screwed in the body by a part which is internally provided with a housing for the clamp presenting the divergent area, the said tubular member holding the washer and the sealing ring in position.

5. An improvement as claimed in claim 1 or 2, wherein the said tubular member constituting the cylindrical housing for the disconnection pusher is crimped into the body, itself forming a housing for the clamp having the divergent area, the said tubular member holding the washer and the sealing ring in position.

6. An improvement as claimed in claim 2, wherein the disconnection pusher is made fast with the spring guiding and supporting the flexible or semi-flexible tube, by screwing said spring into a recessed threading with semicircular threads provided in the pusher and by a crimped part, locking the spring coils in the threading.

7. An improvement as claimed in claim 2, wherein the instant disconnection pusher is made fast with the spring guiding and supporting the flexible or semi-flexible tube by way of an end coil of the spring whose diameter is greater than that of the other coils and which is engaged in a bore of the pusher where it is wedged in by a supported washer, crimped in by a turned-down edge of the pusher, so that the said end coil is set in position inside the pusher and that the remainder of the spring is engaged into the central bore of said pusher.

8. An improvement as claimed in claim 6 or 7, wherein the pusher is provided with an annular groove inside which is turned down a crimped edge of the tubular member and inside which is engaged a locking member.

9. An improvement as claimed in any one of the preceding claims, wherein the locking member of the pusher is constituted by a clip in the shape of a split ring of round, square or rectangular cross-section, and showing a certain resiliency.

10. An improvement as claimed in any one of the preceding claims, wherein the pusher, locked in position by the locking member against the stop means of the cylindrical housing of the tubular member, has an end face which is perpendicular to the axis on the side nearer the clamp, and which acts as a stop means to limit the axial clamping path of said clamp on the tube and prevents excessive clamping of said tube.

11. An improvement as claimed in any one of the preceding claims, wherein a sealing ring is provided between the pusher and the tail of the clamp in the hollow part.

12. An improvement as claimed in claim 11, wherein the sealing ring is held in position against the pusher under the action of a spring with inter-position of a washer.

13. An improvement to instant connectors for flexible and semi-flexible tubes, substantially as hereinabove described with reference to the accompanying drawings.