FR3036066A1 - HITCHING DEVICE FOR ATTACHING AN EXHAUST PACK TO THE BODY OF A MOTOR VEHICLE - Google Patents

Abstract

This hooking device (1) for motor vehicle exhaust pipe comprises a first hollow rod (2) adapted to be fixed to the body of the vehicle, a second hollow rod (6) adapted to be fixed to the exhaust pipe of the vehicle, a stud (10) comprising two bores (13, 14) extending from a front surface (11) to an opposite surface (12) and provided for respectively inserting the free ends (3, 7) therein two hollow rods (2, 6). At least one of the first and second hollow rods (2, 6) is designed so that its free end (3, 7) has a cylindrical tip (16) projecting outside the front surface (11), the hooking device (1) further comprising a locking clamp (20) having two branches (21, 22) adapted to clamp the cylindrical nozzle (16).

Description

The invention relates to the field of mufflers for motor vehicles, and more particularly to the attachment devices of these pots. exhaust at the vehicle body. Conventionally, a stud is used to suitably fix an exhaust pipe to the body of a motor vehicle. This stud may be a piece of any shape comprising a front surface and a posterior surface. Such a stud may comprise two bores extending from the front surface to the posterior surface. These attachment devices further comprise a first hollow rod, or cash hook, and a second hollow rod, or muffler hook. The first hollow stem and the second hollow stem respectively comprise a free end and a flush end respectively. The embedding end of the first hollow rod is secured to the vehicle body by a conventional assembly method. In the same way, the recessed end of the second hollow rod is secured to the muffler. The two bores of the stud are adapted to insert respectively the free ends of the first hollow rod and the second hollow rod. In this way, and by ensuring that the free ends of the hollow rods remain inside the two holes, it is possible to suspend the exhaust line to the vehicle body in a suitable manner.

An example of a solution for maintaining the free ends in the bores is to provide the free ends with two radial protuberances, intended to abut respectively against the front surface and the opposite surface of the stud. The radial protuberances are wider than the bores of the stud, 3036066 2 so that the free end of the hollow rod is stationary, at a displacement, relative to the stud. During assembly on the vehicle, the free ends are fitted into the bores, applying a sufficiently high fitting force 5 to elastically deform the radial protuberance situated at the end. It deforms to be narrower than the diameter of the bore, which allows the insertion of the free end, then substantially returns to its original shape, which allows its retention in the inserted position.

However, the realization of such a hooking device requires a significant effort to grip the free ends of the hollow rods in the holes. Moreover, this solution has the disadvantage of being difficult to dismount when repairing the vehicle, for example in after-sales service.

One solution to this problem is to lubricate the bores of the stud to facilitate fitting. However, such a solution significantly reduces the holding in position of the free ends in the bores. In view of the above, the object of the invention is to provide an attachment device for a muffler that is as strong as possible, requiring the least effort for its installation and offering the possibility of being disassembled. in after-sales. For this purpose, an attachment device for a motor vehicle exhaust pipe, comprises a first hollow rod adapted to be fixed to the body of the vehicle, a second hollow rod adapted to be fixed to the exhaust pipe of the vehicle, a stud comprising two bores extending from a front surface to an opposite surface and provided for respectively inserting the free ends of the two hollow rods.

In addition, at least one of the first and second hollow rods is designed so that its free end has a cylindrical tip protruding outside the front surface, the hooking device further comprising a clamp 3036066 3 locking comprising two branches adapted to tighten the cylindrical tip. Such a coupling device, comprising one or two locking pliers, has in particular the advantages of being easily put in place during assembly of the vehicle and of being able to remain dismountable in after-sales service. According to one embodiment, each of the two branches has a cylindrical inner surface of diameter substantially equal to that of the cylindrical endpiece.

It can further be provided that said tip comprises a radial bore, the locking clip comprising a lug adapted to be inserted into the radial bore. In such an embodiment, said radial bore may open.

It can further be provided that the locking clip comprises a washer portion to be pressed against the front surface of the stud. According to another embodiment, the clamp comprises two tongues each secured to one of the two branches.

It can further be provided that each hollow rod comprises a radial protuberance intended to abut against the surface of the stud opposite to said front surface. In one embodiment, the clamp comprises a deformable portion in the form of a flexible plane, comprising an inner surface 25 at cylindrical rest and of diameter substantially equal to that of the cylindrical endpiece. In such an embodiment, each branch of the locking clamp comprises an inner portion connected at one of its ends to the deformable portion and at the other of its ends to a connecting portion, and an outer portion connected at one of its ends to the connecting portion and at the other of its ends to a tab. In one embodiment, the stud may be made of rubber.

Further advantages and features of the invention will become apparent upon consideration of the detailed description of non-limiting embodiments of the invention, and the accompanying drawings, in which: FIG. embodiment according to the invention of attachment device of a muffler to a vehicle body, - Figure 2 is an isometric view of the attachment device of Figure 1, not provided with the locking clamps, and FIG. 3 is an isometric view of one of the locking pliers of the attachment device of FIG. 1. Referring to FIG. 1, a fastening device 1 for a motor vehicle exhaust pipe comprises a first hollow rod 2, which can be secured to the body of the automobile vehicle. The first hollow rod 2 comprises a free end 3. Subsequently, the free end 3 designates the portion of the hollow rod 2 located on the left, with respect to FIG. 1, of the dotted line 37. The hollow rod 2 comprises also a recessed end 4, not shown in Figure 1. The mounting end 4 is relative to the attachment device in the extension of the arrow pointing upwards shown in Figure 1. The embedding end 4 comprises material means for securing the first hollow rod 2 with the vehicle body. For example, the embedding end 4 may include a surface to be bolted to a corresponding surface of the vehicle body. The first hollow stem 2 is tubular in shape and may include curvatures such as curvature 5. On the other hand, the hollow stem 2 may be hollowed over its entire length, or only on disjoint portions including the stem portion. hollow 2 shown in Figure 1. The hollow rod 2 is made of a metallic material, such as steel.

In the same way, the attachment device 1 comprises a second hollow rod 6, comprising a free end 7 and a mounting end 8 (not shown in FIG. 1). Thanks to the design of the embedding end 8, the second hollow rod 6 can be made integral with the muffler of the motor vehicle. The portion of the second hollow rod 6 shown in FIG. 1, notably comprising the free end 7 and a bend 9, is substantially identical to the portion of the first hollow rod 2 shown in FIG.

The attachment device 1 also comprises a stud 10. The stud 10 is a piece of any shape, for example a cube, a rectangular parallelepiped, a cylinder ... The stud 10 comprises a front surface 11 and an opposite surface 12. Opposite surface 12 is substantially opposite to front surface 11. In this embodiment, surfaces 11 and 12 are both contained in two substantially parallel planes. The stud 10 comprises a first hole 13 and a second hole 14. The holes 13 and 14 are cylindrical, and extend from the front surface 11 to the opposite surface 12. The axis of the bores 13 and 14 is substantially perpendicular to the planes of the surfaces 11 and 12. In other words, the holes 13 and 14 are open. Furthermore, the bores 13 and 14 are of diameter substantially equal to the diameter of the free ends 3 and 7 of the hollow rods 2 and 6. The bores 13 and 14 are thus provided to insert the free ends 3 and 7 of the hollow rods 2. and 6. In this embodiment, the stud 10 is made of rubber. This provides an optimal elasticity of the connection between the vehicle body and the muffler. This may also contribute to reducing the wear of the free ends 3 and 7 and 30 of the stud 10. With reference to FIGS. 1 and 2, the shape of the free end 3 of the first hollow rod 2 will now be described. ci being substantially identical to the shape of the free end 7 of the second hollow rod 6.

As can be seen in FIG. 1, the free end 3 of the first hollow rod 2 comprises a radial protuberance 15. The radial protuberance 15 corresponds to a local increase in the diameter of the tubular surface constituting the first hollow rod 2.

This increase is such that the maximum diameter of the section of the protuberance is substantially greater than the diameter of the bores 13 and 14. The radial protuberance 15 is intended to abut against the opposite surface 12 of the stud. When the radial protuberance 15 abuts against the opposite surface 12, as shown in FIG. 1, any leftward movement of the hollow rod 2 relative to the stud 10 is impossible. It is said that the free end 3 is in its operating position. Furthermore, the radial protuberance 15 is located so that, when the free end 3 is in its operating position, a cylindrical tip 16 of said free end 3 protrudes out of the front surface 11. L cylindrical end piece 16 is shown in axial section in FIG. 1 on the left (with respect to FIG. 1) of a dotted line 38.

The cylindrical tip 16 is shown in FIG. 2 in perspective. In this embodiment, the tip 16 has a substantially cylindrical shape whose axis of cylindricity corresponds to that of the free end 3. The tip 16 consists mainly of a volume between a cylindrical outer surface 17 and a cylindrical inner surface 18. As shown in Figure 1, the outer and inner diameters of the respective outer 17 and inner 18 surfaces are substantially equal to the inner and outer diameters of the free end 3 of the hollow rod 2. In this way, the tip 16 is a hollow extension of the hollow rod 2 or of the hollow rod 6. The cylindrical endpiece 16 furthermore comprises a bore 19, visible in particular in FIG. 2. The bore 19 is substantially cylindrical, directed in the radial direction of the endpiece The bore 19 extends from the outer surface 17 to the cylindrical axis of the tip 16. In this embodiment, the bore 19 extends from the outer surface 17 to the surface. In this way, the bore 19 is opening. The attachment device 1 furthermore comprises a locking clip 20, shown in isometric view in FIG. 3. The locking clip 20 and the cylindrical end piece 16 are designed in such a way as to be able to cooperate in order to maintain the clip. in position of the free end 3 or 7 of the hollow rod 2 or 6 in the stud 10. As can be seen in FIG. 3, the locking clip 20 has a plane of symmetry. The locking clamp 23 comprises a first branch 21 and a second branch 22 symmetrical. The first branch 21 comprises an inner portion 23, a connecting portion 24 and an outer portion 25. The inner portion 23 is a volume extending between an inner surface 26 and an outer surface 27, of small thickness relative to the length or width of the surfaces 26 and 27. The surfaces 26 and 27 are substantially cylindrical. The diameter of curvature of the cylindrical surface 26 is substantially equal to the diameter of the cylindrical tip 16 of one of the rods 2 and 6. Like the inner portion 23, the outer portion 25 is a thin volume extending between the surfaces 28 and 29. The diameter of curvature of the surface 29 is greater than that of the surface 28, itself greater than that of the surface 27. The connecting portion 24 is connected at its two ends respectively to one end of the inner portion 23 and at one end of the outer portion 25. The connecting portion is in the form of a tongue bent at 180 °, so that the outer portion 25 is located facing the inner portion 23, by relative to the radial direction of the cylindrical surfaces. The second branch 22 includes the same features, which can be deduced by symmetry. It is possible to see in FIG. 3 the external surfaces 29 and 27 of the respective external and internal portions 23 of the second branch 22 and the internal surfaces 26 and 28 of the respective inner and outer portions 23 of the first branch 21.

The locking clip 20 comprises a first tongue 30 connected to the outer portion 25 of the first leg 21. More specifically, the tongue 30 is connected to the end of the leg 21 which is opposite to the end connected to the connecting part 22.

In the same way, the locking clip 20 comprises a second tab 31 connected to the outer part 25 of the second branch 22. The locking clip 20 comprises a deformable part 32. The deformable part 32 may be of lesser thickness than the internal parts 23 or external 25 branches 21 and 22, 10 or made of a different material. The deformable portion 32 is designed so that at rest, its inner surface (hidden in Figure 3) has a substantially cylindrical shape of diameter equal to that of the cylindrical tip 16. The deformable portion 32 further comprises a lug 33.

The lug 33 has a cylindrical shape with a diameter substantially equal to that of the bore 19 of the nozzle 16. The lug 33 is of greater length than the depth of the bore 19. The locking clamp 20 comprises a portion forming a washer constituted a first wing 34 and a second wing 35.

The first and second wings 34 and 35 are respectively connected to one side of the outer portions 21 and 22. The wings 34 and 35 have a substantially planar shape. More precisely, the wings 34 and 35 are substantially oriented in a plane perpendicular to the axis of cylindricity of the cylindrical surfaces 26 and 27 constituting the clip 20.

The wings 34 and 35 each comprise at their ends two flaps 36. These are in particular visible in FIG. 1. During assembly of the vehicle parts, it is then possible to introduce the free ends 3 and 7 of the hollow rods. 2 and 6 in the bores 13 and 14 of the stud 10, as shown in FIG. 1. More precisely, the free ends 3 and 7 have been inserted in such a way that the radial protuberances 15 of the rods 2 and 6 are in contact with the opposite surface 12 of the stud 10. Thanks to the design of the free ends 3 and 7, the two cylindrical ends 16 belonging respectively to the rods 2 and 6 3036066 9 project outside the front surface 11 of the stud 10, respectively in the extension of the holes 13 and 14. It is then possible, on each pierced tip, to set up a locking clamp 20 to ensure the maintenance in position of the 5 free ends 3 and 7. To do this, we e It has the effect of moving the branches 21 and 22 of the clamp 20 away. The clamp can then be placed around the end piece 16, the washer part being pressed against the end plate. front surface 11 of the stud 10, as shown in FIG. 1. The arrangement of the clamp 20 with respect to the tip 16 is modified so as to introduce the pin 33 into the piercing 19. lug 33 introduces, releasing the approaching pressure of the tongues 30 and 31. The branches 21 and 22 then approach and enclose the tip 16 in the manner of a conventional clamp.

In this way, the locking clip 20 is securely attached to the free end 3 or 7 of the shank 2 or 6. Thanks to the wings 34 and 35 of its washer portion, the locking clip 20 makes it possible to avoid any movement, apart from a certain deflection, of the stud 10 with respect to one of the free ends 3 or 7. The strength of the holding provided by the locking tongs 20 is partly ensured by adhesion. Indeed, the clamping of the clamp on the tip results in a normal pressure applied by the internal surfaces of the branches 21 and 22 on the outer surface 17. This normal pressure generates a tangential grip force to maintain the position 25 of the locking clamp 20 on the tip 16. To vary the strength of the holding position, one can change the shape at rest of the deformable portion 32, for example by decreasing its diameter of curvature. As a result, the normal pressure exerted by the branches 21 and 22 on the outer surface 18 is increased. In addition, the inner surfaces 24 of the clamp 20 or the outer surface 18 can be treated alternatively so as to increase their adhesion coefficient. This has the consequence, for the same normal pressure exerted by the surfaces 24 on the surface 18, to increase the adherence force generated.

In this embodiment, the locking clip 20 advantageously has a lug 33 adapted to cooperate with a bore 19 of the tip. This makes it possible to significantly increase the strength of holding the clamp 20 in position on the endpiece 16.

To deliberately disassemble the clamp 20 of the tip 16, for example to disassemble the exhaust line of the vehicle, it is then sufficient to perform the actions implemented during assembly, in the opposite direction. The locking clip 20 is advantageously made of one and the same material. For example, the clamp 20 may be made of plastic by various manufacturing method, such as plastic injection. As a result, this attachment device allows the hollow rods to be placed in the bores of the stud and to ensure that they are smooth. maintenance at the cost of a relatively small fitting force compared to the disengagement effort that this assembly is supposed to hold. It is then possible to securely fasten the exhaust line of a vehicle to the body. In addition, the invention makes it possible to adjust the strength of the holding 20 in position, by playing on the materials used, on the surface adhesion coefficients or on the rest shape of parts of the locking clip. Finally, such a fastening device is dismountable after-sale, without causing the destruction of certain parts.

Claims (10)

REVENDICATIONS1. Fastening device (1) for motor vehicle exhaust pipe, comprising a first hollow rod (2) adapted to be fixed to the body of the vehicle, a second hollow rod (6) adapted to be fixed to the exhaust pipe of the vehicle, a stud (10) comprising two bores (13, 14) extending from a front surface (11) to an opposite surface (12) and provided for respectively inserting the free ends (3, 7) therein of the two hollow rods (2, 6), characterized in that at least one of the first and second hollow rods (2, 6) is designed so that its free end (3, 7) comprises a cylindrical end (16) protruding outside the front surface (11), the attachment device (1) further comprising a locking clip (20) having two legs (21, 22) adapted to clamp the cylindrical end (16) . 2. Fastening device (1) according to claim 1, characterized in that each of the two branches (21, 22) has a cylindrical inner surface (24) of diameter substantially equal to that of the cylindrical tip (16). 3. Fastening device according to one of claims 1 and 2, characterized in that said tip (16) comprises a bore (19) radial, the locking clip (20) comprising a lug (33) adapted to be inserted in the radial bore (19). 4. Fastening device according to claim 3, characterized in that said bore (19) radial is open. 5. Fastening device according to any one of claims 1 to 4, characterized in that the locking clip (20) comprises a washer portion (35) intended to be pressed against the front surface (11) of the stud ( 10). 6. Fastening device (1) according to any one of claims 1 to 5, characterized in that the clamp (20) comprises two tabs (30, 31) each secured to one of the two branches (21, 22). ). 3036066 12 7. Fastening device (1) according to any one of claims 1 to 6, characterized in that each hollow rod (2, 6) comprises a radial protuberance (15) intended to abut against the surface (12) stud (10) opposite said front surface (11). 8. Fastening device (1) according to any one of claims 1 to 7, characterized in that the clamp (20) comprises a deformable portion (32) in the form of a flexible plane, comprising an inner surface at cylindrical rest and of diameter substantially equal to that of the cylindrical tip (16). 9. Fastening device (1) according to claim 8, characterized in that each branch (21, 22) of the locking clamp (20) comprises an inner portion (23) connected at one of its ends to the deformable portion (32) and at the other end thereof to a connecting portion (24), and an outer portion (25) connected at one end to the connecting portion (24) and to the other of its ends to a tongue (30, 31). 10. Fastening device (1) according to any one of claims 1 to 9, characterized in that the stud (10) is made of rubber.