FR2797674A1 - DEVICE FOR CONNECTING A RIGID PIPE SECTION TO AN ORGAN - Google Patents

Abstract

Connection device comprising a tubular connector (1) having a first end (2) for connection to a member and an opposite second end (3) for connection to a rigid pipe section, the connector being provided with internal means for securing it to sealingly the section of pipe which comprises an annular retaining element (16) radially and elastically deformable, received in a longitudinal housing (12) delimited by a frustoconical surface (13) of the connector tapering towards the second end thereof, the retaining element being axially movable in the housing between a position for passage of the pipe section, in which the retaining element extends on the side of the first end and has an internal diameter substantially equal to an external diameter of the section pipe, and a position for jamming the pipe section, in which the retaining element extends on the side d e the second end and the frustoconical surface of the housing constitutes a means of constricting the retaining element reducing the internal diameter of the latter so that the retaining element bites the external surface of the pipe section.

Description

The present invention relates to a device for connecting a section of

  rigid pipe to a member of a conductive circuit of pressurized fluid, for example hydraulic or pneumatic, such as another pipe, a tank, a pump ... A connection device generally comprises a tubular connection having a connection end to the member and an opposite end connecting to the pipe section. The connector is provided with an O-ring sealing the connection to the pipe section and means for retaining the section of pipe.

  pipe in the tubular connection.

  There are instant type connection devices in which the retaining means comprise for example a washer with deformable claws between a retaining position in which the claws protrude inside the connector to bite the external surface of the pipe and a release position in which the claws are deformed to be

  radially spaced from the pipeline.

  Such connection devices allow quick and automatic connection and are commonly used in pneumatic circuits. On the other hand, these connection devices are unsuitable for circuits transporting fluids at higher pressures, the claws undergoing at these pressures mechanical stresses such that they risk being deteriorated to the point of no longer being able to ensure the retention of the pipeline. . It would therefore be advantageous to have instantaneous connection devices capable of being used in pressurized fluid circuits

  relatively high such as hydraulic circuits.

  To this end, provision is made, according to the invention, for a connection device comprising a tubular connector having a first end for connection to the member and a second opposite end by which the pipe section is intended to be introduced into the connector, the connector being provided with internal means for sealingly securing therein the pipe section which comprises an annular retaining element radially and elastically deformable, received in an axial housing delimited by a frustoconical surface of the connector tapering towards the second end of it ci, the retaining element being axially movable in the housing between a position for passage of the pipe section, in which the retaining element extends on the side of the first end and has an internal diameter substantially equal to an external diameter of the pipe section, and a position for jamming the pipe section, in which the retaining element extends on the side of the second end and the frustoconical surface of the housing constitutes a means of constricting the retaining element reducing the internal diameter of the latter so that the retaining element bites the outer surface of the

section of pipeline.

  Thus, the retention of the pipe section in the fitting is ensured by the retaining element which, as it is brought to its wedging position, tightens around the pipe section and secures the latter in the fitting. Then, when a force is exerted on the pipe section tending to extract it from the fitting, the retaining element which encloses the pipe section is automatically driven by the latter towards the second end of the fitting, so that the 'constriction force exerted by the frustoconical surface increases and by reaction the force exerted by the retaining element on the frustoconical surface increases producing a wedging effect which is opposed to the extraction of the pipe section out of the fitting. The connection is like this

particularly resistant.

  In a first embodiment, the retaining element comprises a split rod. The retaining element then has a somewhat fragile structure which can easily be made of metal, which further increases its solidity. According to a second particular embodiment, the internal means comprise a helical spring extending axially in the connector to return the retaining element to its wedging position, the retaining element preferably being formed by at least one end turn of the spring extending from the side of the second end of the fitting. The connection device has

  then a relatively simple and very efficient structure.

  Alternatively in this spring embodiment

  helically, the retaining element comprises a split rod.

  Advantageously, the internal diameter of the retaining element in its passage position is slightly

  less than the outside diameter of the pipe section.

  The retaining element is then always slightly tightened on the pipe section, even when it is in its

passing position.

  Other features and benefits of

  the invention will emerge on reading the description which

  follows particular nonlimiting embodiments of

the invention.

  Reference will be made to the accompanying drawings, in which: - Figure 1 is an axial section view of a connection device according to a first embodiment of the invention, - Figures 2 and 3 are views similar to the Figure 1 of the connection device according to the first embodiment, respectively during and at the end of introduction of a pipe section, - Figure 4 is a view similar to Figure 1 of the connection device according to the first embodiment embodiment, when the pipe section introduced is subjected to a force tending to extract it from the connector, - Figure 5 is a view similar to Figure 1 during an operation of removing the pipe section from the connection device according to this first embodiment, - Figure 6 is an axial sectional view of a connection device according to a second embodiment, - Figure 7 is an elevational view of a retaining element usable in the first er and second embodiments, - Figure 8 is a partial view of the internal surface of this retaining element, - Figure 9 is an axial sectional view of a connection device according to a third embodiment, - the FIG. 10 is a view similar to FIG. 9 during the introduction of a section of pipe into this connection device, - FIG. 11 is a view similar to FIG. 9 of the connection device according to the third embodiment, when the pipe section is subjected

  to an effort tending to extract it out of the fitting.

  With reference to the figures, the connection device according to the invention is intended for connecting a section of rigid pipe A to a channel B of a member C (visible in FIG. 11) of a conductive circuit of pressurized fluid . The pipe section A has an external diameter d and is here a metallic conduit but can also be a conduit made of thermoplastic material fitted or not with a reinforcing fur. The member C can be a transmitter or receiver of fluid and be constituted by another section of pipe, a pump, a reservoir

Or other.

  With reference to FIGS. 1 to 5, the connection device according to a first embodiment comprises a tubular connector generally designated at 1, here produced in two parts screwed one on the other, having an end 2 for connection to the member, and an opposite end 3 delimiting an opening 4 of diameter slightly greater than the outside diameter d of the pipe section A. The connector 1 successively comprises, from the end 2 to the end 3: - a tapped recess 5 intended to receive a threaded end piece integral with the member C, - a recess 6 for guiding the end of the pipe section A which has a diameter substantially equal to the diameter d and is connected to the recess 5 by a shoulder 7 against which the end of the pipe section A is intended to come into abutment, - a recess 8 forming a housing for an O-ring 9 intended to seal the connection of the pipe section A at connection 1, - a recess 10 receiving a helical spring 11 having an internal diameter greater than the diameter d and being in abutment against a washer fixed between the recesses 8 and 10, and - a recess 12 delimited by a conical surface 13 of the connection 1 tapering towards the end 3 to

  connect by a shoulder 14 to the opening 4.

  A guide and passage sleeve 15 having an internal diameter substantially equal to the diameter d is slidably received in the connector 1 to extend astride in the recess 10 and the recess 12. The sleeve 15 has an end 15.1 extending on the side of the end 2 of the connector 1 in the housing 10 and against which the spring 11 bears, and an opposite end 15.2

  extending from the end 3 end in the recess 12.

  A radially resiliently deformable split rod 16 is received in the recess 12 so as to be axially movable between a passage position adjacent to the housing 10 and a wedging position adjacent to the shoulder 14, wedging position towards which the split rod 16 is resiliently returned by the sleeve 15 under the effect of the helical spring 11. In the passage position, the split rod 16 is in a state of rest and has an internal diameter slightly smaller than the diameter d. In the wedging position, the frustoconical surface 13 causes the split rod 16 to constrict, reducing the internal diameter of the latter. The split rod 16 is here made in one

metal such as spring steel.

  The connection of the pipe section A to the connection device is carried out by introducing the pipe section A into the connector 1 through the opening 4. The end of the pipe section then meets the split rod 16 and pushes it towards its passing position opposing the force exerted by the spring

helical 11 (Figure 2).

  The recess 12 has in the vicinity of the recess 10 a diameter sufficient to allow a slight radial expansion of the split rod 16. Thus, when the split rod 16 arrives in its passage position, the split rod 16 moves apart under the force exerted by the pipe section A and lets pass the pipe section A until it comes into abutment against the shoulder 7 (Figure 3). The split rod 16 is then held by the spring 11 in an intermediate position close to the passage position in the recess 12 and slightly encloses the pipe section A. When the circuit is pressurized or during a tensile force exerted on the pipe section A, the pipe section A moves back and carries with it the split rod 16 towards its wedging position. The conical surface 13 then constitutes a means of constricting the split rod 16 which increasingly encloses the section of pipe A and bites into the external surface thereof. By reaction, the friction force exerted by the split rod 16 on the frustoconical surface 13 increases and is opposed to the extraction of the pipe (FIG. 4). A jamming is thus obtained. If the extraction force is very high, the split rod 16 abuts against the shoulder 14 and forms a fixed stop

opposing the release of the tube.

  Disconnection (unlocking) is carried out by pushing the split rod 16 into its passage position using a tool E inserted in a notch 17 (visible only in FIG. 5) formed axially in the edge delimiting the opening 4 To facilitate this operation, it is possible at first to simultaneously push the pipe section A into the connector 1 before removing the pipe at a second time, once the rod split in its passage position. Note that the split rod 16 has penetrated into the wall of the

  section of pipe A under the constriction force.

  Identical or analogous items will bear a

  same reference numeral in the following description of

  second and third embodiments.

  The connection device according to a second embodiment, shown in FIG. 6, has a smaller footprint than that of the connection device

of the first embodiment.

  In the second embodiment, the connector 1 does not include a helical spring 10 or socket 15, and the recess 12 is immediately adjacent to the recess 8. The connector further comprises a tubular unlocking pusher 18 slidably received in the free end 3 of fitting 1 to have a push end 18.1 located in the recess 12 and an opposite operating end 18.2 located outside the fitting. The operation is analogous to that of the previous embodiment. It is understood that when the pipe section A is introduced into the fitting 1, the split rod 16 encloses the pipe section A. When the pipe section is subjected to the pressure of the fluid or to a force tending to extract it from the fitting , the pipe section A retreats into the connector 1 and carries with it the split rod 16 towards the

stuck position of it.

  Unlocking is carried out by pressing the unlocking pusher 18 into the connector 1 with a suitable tool so that the pushing end 18.1

  moves the split rod 16 to its passage position.

  As a variant, for the first and second embodiments described above, it can be provided that, as in FIGS. 7 and 8, the split rod 16 has an internal surface 16.1 having gripping reliefs 16.2 in order to improve the subjugation of the rod split 16 on the pipe section A. With reference to FIGS. 9 to 11, the connection device according to a third embodiment comprises a connector 1 comprising an end 2 here provided with an external thread and seal to be installed in the member C and one end 3 delimiting an opening 4 receiving a tubular unlocking pusher 18 ensuring the guiding of the pipe section A. The connector 1 comprises from the end 2 towards the end 3: - a recess 8 forming a housing for a seal 9 and an attached ring 20, the ring 20 having an internal diameter substantially equal to the external diameter d of

  pipe section A to guide it

  ci, - a cylindrical recess 10 extended by a recess 12 which is delimited by a frustoconical wall 13 tapering towards the end 3 and is connected by a

  shoulder 14 at the opening 4 of the end 3.

  A helical spring 11 is arranged in the connector 1 to have a part 11.1 having an internal diameter greater than the diameter d and extending in the recess 10 bearing against the ring 20, and an opposite part 11.2 comprising at least one end turn ( here two) having an internal diameter slightly smaller than

  diameter d and extending in the recess 12.

  The operation is analogous to that of the

previous achievements.

  It is understood that when the pipe section A is introduced into the connector 1 by the pusher 18 received in the opening 4, the turns 11.2 enclose the pipe section A as did the split rod of the modes of

previous achievements.

  When the circuit in which the connection device is installed is pressurized, the pipe section A has a recoil movement tending to extract it from the fitting, and then drives the turns 11.2 into their wedging position, thereby increasing the constriction exerted on them by the frustoconical surface 13, as well as consequently the force which they exert on the external surface of the pipe section and by reaction the force which they exert on the frustoconical surface 13, to produce the jamming

of said section.

  Of course, the invention is not limited to the embodiment described and it is possible to make alternative embodiments without departing from the scope of the invention such as

defined by the claims.

  In particular in the first embodiment, the split rod 16 may also have in its rest state an internal diameter equal to or slightly greater than the

diameter d.

Claims (8)

  1. Device for connecting a channel of an organ to a rigid pipe section, comprising a tubular connector (1) having a first end (2) connecting to the organ and a second opposite end (3) through which the pipe section is intended to be introduced into the fitting, the fitting being provided with internal means for sealingly securing the pipe section to it, characterized in that these internal means comprise an annular retaining element (16, 11.2) radially and elastically deformable, received in a longitudinal housing (12) delimited by a frustoconical surface (13) of the connector narrowing towards the second end thereof, the retaining element being axially movable in the housing between a position for passage of the pipe section, in which the retaining element extends on the side of the first end and has an internal diameter substantially equal to a diameter ex dull section of the pipe, and a stuck position of the pipe section, in which the retaining element extends on the side of the second end and the frustoconical surface of the housing constitutes a means of constricting the retaining element decreasing the internal diameter of it so that the retainer bites the   outer surface of the pipe section.   2. Connection device according to claim 1, characterized in that the retaining element comprises a split rod (16).   3. Connection device according to claim 1, characterized in that the internal means comprise a helical spring (11) extending axially in the connector (1) to return the retaining element (16, 11. 2) towards its stuck position.   4. Connection device according to claim 3, characterized in that the retaining element is formed by at least one end turn (11.2) of the spring (11) extending   on the side of the second end (3) of the fitting (1).   5. Connection device according to claim 3, characterized in that the retaining element comprises a split rod (16).   6. Connection device according to any one   of the preceding claims, characterized in that the   internal diameter of the retaining element (16, 11.2) in its passage position is slightly less than the diameter   of the pipe section.   7. Connection device according to any one   of the preceding claims, characterized in that   the retainer (16, 11.2) has an internal surface   (16.1) comprising cramp reliefs (16.2).   8. Connection device according to any one   of the preceding claims, characterized in that it   comprises a tubular release pusher (18) sliding in the free end (3) of the fitting (1) and having, inside the fitting, a pushing end (18.1) of the retaining element (16, 11.2 ) and, outside the fitting, an opposite end (18.2) of push button operation.