AUTOMATIC FLUID PIPE CONNECTION DEVICE WITH LOCKING SYSTEM

Abstract

Automatic pipe connection device comprising a nozzle successively having a front cylindrical part entering into an annular seal of a sleeve (2) by tightening it, a conical part which opens then a circular locking groove, the sleeve (2) comprising a locking pin (10) having two sides (12) ending in axial hooks (16) which in a high position of the pin (10) keep these sides (12) spaced outwards, and in a low position allows the sides (12) to come together by coming into the locking groove, this device comprising a locking ring (20) sliding on the sleeve (2), comprising lower edges (30) preventing in a waiting position of the ring (20) the descent of the pin (10), which after a first stroke towards the rear of this ring (20) are released allowing the descent of the pin (10). Figure 1

Description

Title of the invention: AUTOMATIC FLUID PIPE CONNECTION DEVICE WITH LOCKING SYSTEM

[0001] The present invention relates to an automatic fluid pipe connection device comprising a locking system, as well as a method of assembling this device and a motor vehicle comprising a powertrain cooling circuit equipped with such connection devices.

[0002] A type of known automatic connection device, presented in particular by document FR-A1-3119220, comprises a male end piece fixed to the end of a fluid circulation pipe which fits axially into the rear end of a sleeve to form a sealed connection for the passage of the fluid.

[0003] The front end of the nozzle has a cylindrical front part which is guided in a conical shape of the sleeve, to then fit at the bottom in a front bore ensuring guidance between these two elements.

[0004] A front chamfer of the cylindrical part allows entry into an annular seal made of elastomer, arranged in an internal circular groove of the bore of the sleeve, this part then tightening the annular seal in order to obtain a seal resistant to the pressure of the fluid passing through this connection.

[0005] The end piece comprises, after the front cylindrical sealing part, a conical shape which is extended by a rear cylindrical part of larger diameter, comprising a circular locking groove.

[0006] The sleeve comprises towards the rear transverse external grooves receiving the two substantially parallel sides of a pin, which can move apart by elastic deformation.

[0007] When the tip is introduced into the sleeve, there are overlapping axial strokes at the same time the entry of the cylindrical front part into the seal with its compression by the front chamfer, and the conical shape of the tip which separates the parallel sides of the pin to slide them onto its rear cylindrical part. Then at the end of the stroke the sides of the pin tighten as they fall into the circular locking groove of the tip, in order to ensure axial locking of these two parts between them which resists the pressure of the internal fluid.

[0008] The end piece also comprises, towards the rear on its contour, axially elongated ribs which engage in corresponding grooves of the inlet of the sleeve, in order to ensure angular locking between these two parts having significant mechanical resistance.

[0009] During the introduction of the tip, two elastic deformation operations may occur over a partial axial stroke, the compression of the seal and the separation of the sides of the pin, which results in an addition of resistance to the advancement of the tip in the sleeve which may pose problems of significant axial force to be applied to achieve these deformations.

[0010] In particular in a motor vehicle engine compartment comprising a powertrain with several automatic circuit connections to be made, the repetitive nesting operation involving a high effort, in a space which can be reduced, poses ergonomic problems. There is then a risk that operations are carried out incorrectly with a blockage which is not ensured, which can generate breakdowns.

[0011] Furthermore, the pin is removed by simply lifting it. At least partial movement of the pin, which can be done freely, in particular due to wear of the system, incorrect operation or vibrations, does not ensure reliable locking with a circuit which can open under the pressure of the fluid, which poses safety problems.

[0012] The present invention aims in particular to avoid these problems of the prior art.

[0013] To this end, it proposes a device for automatically connecting fluid pipes comprising, along a main axis, a nozzle successively having a front cylindrical part which, when assembled, enters into an annular seal of a sleeve by tightening it, a conical part which opens and then a circular locking groove, the sleeve comprising a locking pin having two sides guided in grooves, ending in hooks which, in a high position of the pin, keep these sides spaced outwards, and in a low position allow the sides to enter the locking groove, this device being remarkable in that it comprises a locking ring sliding on the sleeve, comprising lower edges preventing the pin from descending in a waiting position of the ring, which after a first stroke towards the rear of this ring are released, allowing the pin to descend.

[0014] An advantage of this connection device is that during assembly, the ring being in its forward waiting position, the sides of the pin are maintained in the spaced position of this ring, and do not clamp the opening cone of the end piece during its advancement, which eliminates a force of separation of the sides. A reduced axial assembly force is obtained, mainly comprising the force necessary to compress the annular sealing joint.

[0015] Furthermore, in its rear assembly position, the ring can lock the sides of the pin in their tightened position with an adjustment in the locking groove of the end piece, which constitutes a safety feature preventing this pin from being withdrawn. directly.

[0016] The automatic connection device according to the invention may further comprise one or more of the following characteristics, which may be combined with each other.

[0017] Advantageously, each hook is formed by bending a metal wire which is parallel to the main axis.

[0018] In this case, advantageously in the waiting position the locking ring comprises a lower rim arranged below each hook, and a free space in front of this rim releasing the hook to allow its descent.

[0019] Advantageously, the locking ring has lower edges preventing the pin from rising in the assembly position.

[0020] In addition, advantageously the locking ring comprises two arms each comprising, starting from its rear end, successively the lower edge, the free space and the lower edge.

[0021] Advantageously, the locking ring has an axial sliding force on the sleeve which is greater than the maximum force for engaging the end piece in the seal.

[0022] The invention also relates to a method of assembling a connection device comprising any one of the preceding characteristics, remarkable in that it comprises a step of axial force applied between the end piece and the locking ring.

[0023] In addition, the locking ring comprising lower edges preventing the pin from rising into the assembly position, after the first sliding stroke of the locking ring and the descent of the pin, advantageously the method comprises a following sliding step following a second stroke achieving locking of the pin by the lower edges.

[0024] The invention further relates to a motor vehicle comprising a powertrain equipped with a heat transfer fluid circuit for its cooling, remarkable in that it comprises pipe connection devices comprising any one of the preceding characteristics, connecting pipes of this fluid circuit.

[0025] The invention will be better understood and other characteristics and advantages will appear more clearly on reading the description below given by way of example, with reference to the appended drawings in which:

[0026] [Fig.l] shows a sleeve of an automatic connection device according to the invention with its locking ring in the front position in a position waiting for assembly;

[0027] [Fig.2] is a diagram showing in side view the relative movement of a side hook of the pin of this device;

[0028] [Fig.3] shows the sleeve with its ring in the rear position after assembly; and

[0029] [Fig.4] shows the axial sliding forces of the end piece and the ring during an assembly operation.

[0030] Throughout the document the upper or top side of the connection device is relative to the vertical axis shown in the figures, in the vehicle the connection device can take any orientation.

[0031] Figures 1, 2 and 3 show, along an axis A comprising a front direction AV for introducing a tip not shown, a sleeve 2 comprising successively starting from the rear a first bore 4 receiving in an adjusted manner a rear cylindrical part of the tip, a narrowing cone 6, then a front bore 8 of small diameter receiving a front cylindrical part of this tip.

[0032] A locking pin 10 has two substantially parallel sides 12 fitted into transverse grooves 14 arranged on each side of the first bore 4, which in a waiting position are held apart by elastic deformation without protruding into this bore. Each side ends with an end bent axially forward, forming a hook 16 which remains outside the groove 14.

[0033] The locking pin 10 is arranged in the transverse plane of a circular groove for locking the end piece when it is at the end of its insertion into the sleeve 2.

[0034] Each hook 16 is clamped on a cylindrical outer contour of the end piece 2. When the pin 10 is in the high position, shown [Fig.l], the hooks 16 following this cylindrical contour give a spacing of the sides of the pin 12 which keeps them outside the first bore of the sleeve 4, allowing free sliding of the end piece inside.

[0035] When the pin 10 is in the low position, shown [Fig.3], the hooks 16, following the external contour of the sleeve 2 by elastic return, tighten towards the middle of this sleeve by sliding on this external contour during the descent which allows the sides of the pin 12 to fall into the locking groove of the end piece.

[0036] A locking ring 20 comprises a circular portion covering the top of the sleeve 2, descending below its diameter in order to ensure radial retention on this sleeve while allowing axial sliding. The locking ring 20 comprises in the lower portion two axial arms 22 extending towards the rear, which cover the axial position of the pin 10.

[0037] In the standby position, on each arm 22 an inwardly facing lower rim 30, formed at the bottom and rear end of each arm 22, is arranged below the hook on the side 16 in order to prevent the pin 10 from descending.

[0038] In the backward movement of the ring 20 following a first stroke of this ring XA, the lower edge 30 passes behind the side hook 16 which passes into the position 16A to leave it in a free space which is cleared downwards 32, this hook can then freely descend following the cylindrical contour of the sleeve 2. An automatic descent stroke of the pin 10 is obtained, with its two sides 12 falling into the locking groove of the end piece.

[0039] The operator then continues to apply an axial force on the ring 20 relative to the sleeve, to obtain a second ring stroke XB which causes a lower edge 34 of the arm 22 to pass above the side hook 16 passing into the position 16B. In this final position of the assembly, a blocking of the side hooks 16 is obtained, which are held below the lower edges 34.

[0040] The pin 10 cannot rise directly. Subsequent opening of the connection device, for a subsequent maintenance operation for example, requires a first operation of advancing the ring 20, then a second operation of lifting the pin 10. These two maneuvers prevent a false maneuver from being made which would be easier in the case of a single operation to be carried out.

[0041] [Fig.4] shows, as a function of the axial movements of the sleeve M and the ring B relative to the end piece, the axial force F necessary to achieve this relative movement. For a first stroke of the sleeve XI the front cylindrical end of the end piece slides in the second bore 8 with little resistance giving a first low force level Fl for this advancement.

[0042] For a second stroke of the sleeve X2 the front chamfer of the tip begins to compress the annular sealing gasket, with a resistance which gradually increases until reaching the third force level F3 which is high. At the end of this second stroke X2 the sealing gasket has completely passed over the front cylindrical part of the tip.

[0043] For a third stroke of the sleeve X3 the seal slides on the front cylindrical part of the end piece, with a constant force giving the second force level F2 which is moderate. The friction forces of the locking ring 20 on the outer surface of the sleeve 2 are greater than the third force level F3, this ring does not slide on the sleeve from the first stroke XI to the third stroke X3.

[0044] At the end of travel X3 the end piece is in abutment at the bottom of the sleeve 2, the clip 10 is opposite the locking groove of the end piece.

[0045] In this case, the operator continues to apply an axial force between the end piece and the ring 20, this force increases without relative displacement until it reaches the fourth force level F4 which is greater than the friction forces of the ring 20 on the sleeve 2, which allows the recoil of this ring following the first ring stroke XA.

[0046] Each side hook 16 being lowered, the operator continuing to apply the axial force on the ring 20 we obtain the second ring stroke XB with the edges in lower 34 of this ring which come above the side hooks 16 locking the position of the pin 10.

[0047] An operation for opening the connection device firstly comprises the axial movement forward of the ring 20 along the stroke XB, then the lifting of the pin 10 and finally the second stroke XA of this ring to then allow the removal of the end piece.

Claims

Claims

1. Device for automatic connection of fluid pipes comprising along a main axis a nozzle successively having a front cylindrical part which, when assembled, enters into an annular seal of a sleeve (2) by tightening it, a conical part which opens and then a circular locking groove, the sleeve (2) comprising a locking pin (10) having two sides (12) guided in grooves (14), ending in hooks (16) which, in a high position of the pin (10), keep these sides (12) spaced outwards, and in a low position allows the sides (12) to enter the locking groove, characterized in that it comprises a locking ring (20) sliding on the sleeve (2), comprising lower edges (30) preventing, in a waiting position of the ring (20), the pin (10) from descending,which after a first backward stroke (XA) of this ring (20) are released allowing the pin (10) to descend.,

2. A connecting device according to claim 1, characterized in that each hook (16) is formed by a bend of a metal wire which is parallel to the main axis.

3. Connection device according to claim 2, characterized in that in the waiting position the locking ring (20) comprises a lower rim (30) arranged below each hook (16), and a free space (32) in front of this rim (30) releasing the hook (16) to allow its descent.

4. Connection device according to any one of the preceding claims, characterized in that the locking ring (20) has lower edges (34) preventing the pin (10) from rising in the assembly position.

5. Connection device according to claims 3 and 4, characterized in that the locking ring (20) comprises two arms (22) each comprising, starting from its rear end, successively the lower edge (30), the free space (32) and the lower edge (34).

6. Connection device according to any one of the preceding claims, characterized in that the locking ring (20) has an axial sliding force (F4) on the sleeve (10) which is greater than the maximum engagement force of the end piece in the sealing joint (F3).

7. Method of assembling a connection device according to any one of the preceding claims, characterized in that it comprises a step of axial force applied between the end piece and the locking ring (20).

8. Method for assembling a connection device according to claim 7, the locking ring (20) comprising lower edges (34) preventing the pin (10) from rising in the assembly position, characterized in that after the first sliding stroke (XA) of the locking ring (20) and the descent of the pin (10), it comprises a following sliding step following a second stroke (XB) effecting locking of the pin (10) by the lower edges (34).

9. Motor vehicle comprising a powertrain equipped with a heat transfer fluid circuit for its cooling, characterized in that it comprises pipe connection devices according to any one of claims 1 to 6, connecting pipes of this fluid circuit.

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