FR2824619A1 - Instant connector for plastic-coated metal pipes comprising tubular insert with grooves for seal ring and expanding grip ring - Google Patents

Abstract

The connector consists of a rigid body (2), e.g. of a molded synthetic material, with a tubular insert (3) for each pipe (5) with first and second peripheral grooves (9, 13) for a seal (10) and a split ring (16) with sharp-edged external gripping elements (20). The grip ring and second groove have matching inclined thrust surfaces (15, 19). The connector consists of a rigid body (2), e.g. of a molded synthetic material, with a tubular insert (3) for each pipe (5) having first and second peripheral grooves (9, 13) for a seal (10) and a split ring (16) with sharp-edged external gripping elements (20). The grip ring and second groove have matching inclined thrust surfaces (15, 19) to expand the grip ring as the connector is tightened by an external rigid tubular sleeve (25). The body has a stop collar (24) for the pipe end and the outer sleeve has a window (27) for checking the position of the pipe end and an in-turned edge (26) to engage with the collar. In a variant the tubular inserts can be of metal and the stop collars of synthetic material.

Description

The subject of the present invention is an instant fitting for tubes

  deformable, such as tubes of composite material comprising a metallic core, for example aluminum, coated with layers of synthetic material, for example of crosslinked polyethylene. Such types of tubes are used more and more frequently in the production of heating installations, to conduct water heated by a boiler, as well as in sanitary installations, to conduct domestic water.

hot or cold.

  Instant fittings for tubes have been known for a long time, for example from document EP 0 021 795. In such a fitting, each tube passes through a hooking element comprising claws as well as a seal. Tube attachment and sealing are performed

outside the fitting.

  In the case of deformable tubes, such as the tubes made of the aforementioned composite materials, it is advisable to achieve good attachment of the tube in the fitting, as well as good sealing despite the deformable nature of the tube. The object of the invention is to provide an instant connection ensuring both good attachment and good sealing while being compact. In addition, insofar as the connector is intended for composite tubes comprising an aluminum core, it is advisable to avoid contacts between the aluminum core and the fluid, on the section of the tube, and to avoid contacts between the hanging system and the aluminum layer. Finally, this fitting should allow viewing of the correct

  fitting each tube into the fitting.

  To this end, the connector it relates to comprises a rigid body comprising, for the connection of each tube, a tubular part with an outside diameter corresponding to the inside diameter of the tube, in which are formed a first peripheral groove, situated on the side of the free end of the tubular part, serving as a housing for a seal intended to seal with the interior of the tube, and a second peripheral groove serving as housing for a fastening ring having on an outer face means of attachment intended to cooperate with the inner surface of the tube, the attachment begue being a ring capable of deforming radially. According to the invention, the second groove of the body and the attachment ring have complementary bearing faces each inclined from the inside to the outside and

  towards the free end of the tubular part considered.

  Each tube intended to be fixed in the fitting is simply fitted onto a tubular part of the fitting. It should be noted that both the sealing and the attachment are made at the interior of the tube. If, after assembly, a traction is exerted on the tube, the tube tends to ent ^ 'r towards the end the ibre of the party e tu bu la ire cons id ered the split ring, which tends to increase in section by pressing its inclined face against the inclined face of the groove of the body in which it is housed. This results in an increase in the pull-out resistance of the tube, which cannot be released from the fitting. The seal being placed on the side of the free end of the tubular part, the seal remains perfectly ensured. According to a preferred characteristic of the invention, means for attaching the attachment ring comprise at least one edge which projects outwards and which is intended to penetrate the surface.

inside the tube.

  According to a first possibility, the connector comprises for each tubular part for the connection of a tube, a rigid tubular cap, fixed on the body, with an inside diameter corresponding to the outside diameter of the tube. This solution is advantageous in the case of tubes whose mechanical strength is not sufficient to ensure reliable attachment to

the body.

  According to a second possibility, the connector comprises for each tubular part for the connection of a tube, a metal crimping ring, with an internal diameter corresponding to the diameter

outside of the tube.

  It is thus possible from a single body, depending on the nature of the tube to be connected and according to the components and equipment available to the operator, to produce different variants of the same connector. According to another characteristic of the invention, each tubular part for connecting a tube comprises a flange intended

  to form an axial stop for the tube in the position mounted on the fitting.

  In the case where the fitting includes a cap, the outside diameter of the flange is less than or equal to the inside diameter of the

  tubular colffe, and the colffe also covers the collar.

  In order to allow, in such a case, the display of the correct fitting of the tube, the tubular cover comprises at least one window for displaying the position of the end of the tube in the position mounted on

  the fitting, located near the flange.

  In one embodiment of this fitting, the tubular cap comprises, at its end situated on the side of the middle of the fitting, a part in the form of a hook bent inwardly, intended to carry out the attachment of the barb on the collar of the body. In such a case, the colffe is mounted

  irreversible and the fitting cannot be removed.

  In another embodiment of this fitting comprising a crimping ring, an end zone of the ring is crimped on the external face of the flange, with attachment in at least one groove

  annular or an obviously that includes the collar.

  According to one possibility, each collar is an integral part of the body. The body and the collar can thus be produced for example by

  synthetic material and obtained by molding.

  According to another possibility, each flange is separate from the body and fixed on it. Thus, for example, the body is metallic and each collar is made of synthetic material. This avoids contact on the section of the tube resting against the flange between the aluminum core and a metal part, which could generate torques

Electrolytic.

  According to another characteristic of the invention, each split ring comprises at least one peripheral edge projecting towards the outside and delimited on the one hand by a surface inclined from the inside towards the outside and from one end of the fitting towards the middle. of the latter, on the insertion side of the tube and on the other hand by a surface substantially perpendicular to the axis of the tubular part considered, on the side of the middle of the fitting. Each ring may have one edge or two parallel edges which are axially offset from one another. It should be noted that each edge can be continuous, on the periphery of the begue, or consist of

  several successive sections independent of each other.

  As for the seal, it can be an O-ring, or

  a joint with one or more lips.

  In any case, the invention will be well understood, using the

  description which follows, with reference to the attached schematic drawings

  representing, by way of nonlimiting examples, several embodiments

of this fitting.

  Figure 1 is a perspective view of a connector for the connection between two tubes, one end of which is provided with a ridge and the other end of which does not include a ridge; Figure 2 is a longitudinal sectional view of the connector of Figure 1, in which a tube is engaged in the part of the connector equipped with a barb; Figure 3 is a perspective view of a coupling ring of the connector of Figures 1 and 2; Figure 4 is a perspective view of a second attachment ring; Figure 5 is a perspective view of a joint of the connector of Figures 1 and 2; Figure 6 is a sectional view through a diametrical plane of the seal of Figure 5; Figure 7 is a sectional view similar to Figure 6 of another type of seal; and Figures 8 and 9 are longitudinal section views of two

  fittings fitted with crimping rings.

  The connector shown in FIGS. 1 and 2 comprises a body 2, for example made of synthetic material, having two tubular parts 3 coaxial 3, separated from each other by a central and transverse shoulder 4. The body 2 is tubular, and its outside diameter corresponds to the inside diameter of a composite tube 5 comprising an aluminum core 6 coated on its inside and outside faces with two layers of synthetic material 7 and 8, for example polyethylene

crosslinked or not.

  Each tubular part 3 being identical, only one of them is described below. A tubular part 3 comprises, from its free end, a groove 9, serving to accommodate a seal 10 comprising

  a single lip 12, this seal being shown in detail in FIGS. 5 and 6.

  On the middle side of the fitting, each tubular part 3 has a groove 13 having from the middle of the fitting towards the free end of the tubular part, an area with a bottom 14 parallel to the axis of this tubular part extended towards the 'free end of this tubular part S by an inclined face 15 from the inside to the outside, and from the middle of the fitting towards the free end of the tubular part. This groove 13 is used for housing a ring 16, for example made of synthetic material. This ring 16, shown in more detail in Figure 3, is preferably but not exclusively, a begue open by an axial slot 17. This ring has a bearing surface 18 on the surface 14 of the groove 13, and a surface 19 with the same inclination as the surface 15 of the groove 13, intended to bear against the latter. In the embodiment shown in FIGS. 1 to 3, the ring 16 comprises, as attachment means, a continuous peripheral edge 20 projecting outwards and delimited by a surface 22 inclined from the inside towards the outside and from the free end of the fitting towards the middle thereof, and a face 23 substantially perpendicular to the axis of the tubular part considered, located on the side of the middle of the fitting. Each tubular part also includes a peripheral flange 24 intended to form an axial stop for a tube 5 in the position mounted on the connector. In the form of execution

  shown in the drawing, this flange is an integral part of the body 2.

  This connector also comprises, surrounding each tubular part, a rigid tubular cap 25 fixed to the body, with an inside diameter corresponding to the outside diameter of the tube. The purpose of this flange is to ensure perfect retention of the tube 5, in particular if the latter is deformable. The cap 25 has, at its end situated on the side of the middle of the body, a part 26 curved inwards, forming a hook coming to engage behind a flange 24, thus ensuring an irreversible mounting of the barb on the body. Of course, any other method of assembly between the body and the cap could be envisaged such as, for example, but not exclusively, by crimping a metal piece or by threads arranged on the barb and the body. Windows 27 are provided in the wall 25, near the flange 24, for

  view the correct fitting of a tube 5 on the fitting.

  In practice, the operator engages a tube 5 on the body 2, in the space between a tubular part 3 of the latter and a bar 25, until the tube is in abutment against a flange 24. This movement is made possible taking into account the radial deformability of the hooking ring 16. In the fitted position, the edge 20 of the ring 16 penetrates into the inner layer 7 of the tube 5, and ensures the retention of the latter. The fluid is sealed using the seal 10. If an attempt is made to remove the tube accidentally or not, the inclined face 19 of the ring bears on the inclined face 15 of the groove 13, this which tends to increase the diameter of the split ring 16 and to improve the attachment of the ring in the inner layer 7 of the tube, making it impossible to

withdrawal of it.

  FIG. 4 represents a variant of the ring 16, in which two edges 20 are provided, parallel and axially offset

one in relation to the other.

  FIG. 7 represents a seal 10 comprising several

lips 28.

  Figures 8 and 9 show two variants of the connector according to the invention in which the same elements are designated by the

  same references as before.

  In the embodiment shown in Figure 8, the tubular part 3 is provided on its outer face with a seal 28 of circular section. The end of the tube 5 is held by crimping a metal ring 29 using jaws 30. An end zone of the ring 29 is supported on the outer face of the flange 24, and is retained on the latter by hooking in a circular groove 32. A notch 34 formed on the outer surface of the part

  tubular 3 also promotes retention of tube 5.

  In the embodiment shown in Figure 9, the retention of the metal ring 29 on the outer face of the flange 24 is

  produced by hooking in a recess 33 adjacent to the shoulder 4.

  It goes without saying that the invention is not limited to the sole embodiments of this connection, described above by way of examples, on the contrary, it embraces all variants. Thus, in particular, this connector could be a T-connector and include three tubular parts intended to receive three tubes. Furthermore, this connection may not include a tubular collar if the tubes to be connected are sufficiently rigid. Likewise, the seal could be an O-ring, or several seals could be provided, without thereby leaving the

part of the invention.

  In addition, according to the example illustrated, the means for hooking the ring comprise a continuous edge. However, the attachment means S could comprise one or more discontinuous edges or not. Likewise, the attachment means could be produced in any other appropriate manner insofar as they are capable of generating adhesion, of the ring 16 on the tube to be connected 5, sufficient for the ring to be able to follow the movements of the tube especially during a withdrawal movement of the tube. Thus, the attachment means could also be produced in the form of a cross knurling defining a

  rough surface for attaching the ring to the tube.

Claims (13)

  1. One-touch fitting for deformable tubes, such as in particular tubes made of composite material comprising a metal core, for example aluminum, coated with layers of synthetic material, for example crosslinked polyethylene, characterized in that it comprises a rigid body ( 2) comprising, for the connection of each tube (5), a tubular part (3) of external diameter corresponding to the internal diameter of the tube (5), in which are formed a first peripheral groove (9), located on the side of the free end of the tubular part, serving as housing for a seal (10) intended to seal with the interior of the tube, and a second peripheral groove (13) serving as housing for a hooking ring (16) having an attachment means (20) on an outer surface intended to cooperate with the inner surface of the tube (5), the attachment ring (16) being a ring capable of deforming radially, and the second groove (13) of the body (2) and the attachment ring (16) having complementary bearing faces (15, 19) each inclined from the inside towards the outside and   towards the free end of the tubular part considered.   2. One-touch fitting according to claim 1, characterized in that it comprises, for each tubular part (3) for the connection of a tube (5), a rigid slide cap (25), fixed on the body (2), of diameter   inside corresponding to the outside diameter of the tube (5).   3. Instant fitting according to claim 1, characterized in that it comprises, for each tubular part (3) for the connection of a tube (5), a crimping ring (29), of corresponding internal diameter the outside diameter of the tube.   4. Instant connection according to one of claims 1 to 3,   characterized in that each tubular part (3) for the connection of a tube (5) comprises a flange (24) intended to form an axial stop   for the tube (5) in position mounted on the fitting.   5. One-touch fitting according to claim 4, characterized in that the outside diameter of the flange (24) is less than or equal to the inside diameter of the tubular collar (25) or of the ring. crimping (29).   6. One-touch fitting according to claim 5, characterized in that the tubular cover (25) comprises at least one viewing window (27) of the position of the end of the tube (5) in the position mounted on the   fitting, located near the flange (24).   7. One-touch fitting according to claim 5, characterized in that the tubular collar (25) comprises, at its end situated on the side of the middle of the fitting, a part (26) in the form of a hook bent inwards, intended to make hooking the cap (25) on the flange (24) of the body.   8. One-touch fitting according to claim 5, characterized in that an end zone of the crimping ring (29) is crimped on the outer face of the flange (24) with attachment in at least one   annular groove (32) or a recess (33) that it comprises.   9. One-touch fitting according to claim 4, characterized in that   that each flange (24) is an integral part of the body (2).   10. One-touch fitting according to claim 4, characterized in   that each flange (24) is separate from the body (2) and fixed on the latter.   11. One-touch fitting according to claim 10, characterized in that the body is metallic and each flange is made of material synthetic.   12. One-touch fitting according to one of claims 1 to 11,   characterized in that each split ring (16) comprises, as hooking means, at least one peripheral edge (20) projecting outwards and delimited on the one hand by a surface (22) inclined from the inside outwardly and from one end of the connector towards the middle thereof, on the insertion side of the tube and on the other hand by a surface (23) substantially perpendicular to the axis of the tubular part considered, from middle side of the fitting.   13. One-touch fitting according to one of claims 1 to 11,   characterized in that the fastening means comprise at least one edge (20) projecting outwards and intended to penetrate the surface