Device for attaching one end of an anti-roll bar to a vehicle's suspension system, and associated vehicle.
Patent Information
- Application Number
- FR2022014291
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-12-22
- Publication Date
- 2025-02-28
- Estimated Expiration
- 2042-12-22
AI Technical Summary
The traditional manufacturing process for fixing the ends of an anti-roll bar to a vehicle suspension system is demanding and difficult to implement, particularly due to the need for forging and screwing, which can lead to weak welds and threading issues under alternating stresses.
A device for fixing the anti-roll bar to the suspension system using a fixing insert with a cylindrical body and support head, featuring radial protrusions for additional support and a threaded connection to distribute stress, reducing reliance on welds and improving robustness.
The solution provides a robust and easy-to-manufacture fixing device that withstands alternating stresses by distributing forces through radial protrusions and a threaded connection, enhancing durability and reducing manufacturing complexity.
Abstract
Description
Description Title of the invention: Device for attaching one end of an anti-roll bar to a vehicle suspension system, and associated vehicle. Technical field
[0001] = The invention relates, in general, to any system comprising a pivot of ball joint to be secured, and in particular such a system evolving in a vi-
[0002] — The invention relates more specifically to an anti-roll bar for a vehicle au- automobile, and more particularly relates to a device for fixing the ends from the anti-roll bar to a vehicle suspension system
[0003] Prior Art
[0004] — For several decades, motor vehicles have been equipped with at least less an anti-roll bar, also called an anti-roll bar or stabilizer bar, which consists of a metal part, for example steel, substantially U-shaped circular section and which limits the inclination of the vehicle in curves or in potholes. Such an anti-roll bar connects at each of its ends one of the two suspension systems of the same set of wheels of the vehicle. Each end of the anti-roll bar is therefore linked to the suspension system of one of the wheels of the same wheel set using a fixing device.
[0005] Traditionally, this fixing device is formed by a screwed connection. More particularly, the end of the anti-roll bar is heated and forged to be crushed, bent and then drilled, in order to receive a screw and a nut. A connecting rod is connected by a first end to the suspension system intended to be connected to said end of the anti-roll bar. The opposite end of this link is secured via the screw and nut at the said end of the anti-roll bar.
[0006] However, the manufacturing process is demanding and proves difficult to implement. work, particularly with regard to obtaining such geometry of the ends anti-roll bar.
[0007] — To eliminate these difficult-to-implement forging steps, a device for fixation according to [Fig.1] was developed.
[0008] = [Fig.1] therefore shows a partial perspective view of a vehicle au- car 1 equipped with an anti-roll assembly 2 according to the prior art.
[0009] — The anti-roll assembly 2 comprises an anti-roll bar 3, also called an anti-roll bar anti-roll bar or stabilizer bar. The anti-roll bar 3 is, as is known, a part metallic, for example steel, substantially U-shaped and circular in cross-section. The anti-roll bar 3 thus comprises two identical lateral arms 3a, and a central section 3b connecting the two lateral arms 3a by one of their ends. Each of the lateral arms 3a thus comprises one end linked to the central section 3b and an opposite free end. The anti-roll bar 3 is fixed to the vehicle chassis | by bearings 1a and 1b partially enclosing the central section 3b. For the same set of front or rear wheels of the vehicle 1, the vehicle | comprises a suspension system 4 associated with each of the wheels. The vehicle 1 therefore comprises a suspension system 4 for the left wheel and a suspension system 4 for the right wheel. Each suspension system 4 is connected to the anti-roll assembly 2 via an identical fixing device 5. Subsequently, only one of the fixing devices 5 will be described, for example the fixing device 5 of the left wheel, everything described being symmetrical and identical for the right side. The fixing device 5 comprises a connecting rod 6 and a means 7 for fixing the connecting rod to the anti-roll bar 3. The connecting rod 6 is a metal rod comprising a first end formed by a first ball joint 7a and a second opposite end formed by a second ball joint 7b. The first ball joint 7a connects the connecting rod 6 to the anti-roll assembly 2, and more precisely to the anti-roll bar 3, while the second ball joint 7b connects the connecting rod 6 to the suspension system 4. The ball joints 7a and 7b thus allow the connecting rod 6 in a known manner to orient itself according to the relative movement of the suspension system 4 with respect to the anti-roll bar 3. The fixing means 7 comprises a fixing insert 8 and a connecting member 9 of the connecting rod to the fixing insert illustrated in partial longitudinal section in [Fig.2]. The fixing insert 8 comprises a support head 8a and a cylindrical body 8b of substantially circular section and of constant diameter less than the diameter of the circular section of the anti-roll bar 3. The support head 8a constitutes one of the ends of the cylindrical body 8b and forms a collar of diameter greater than the diameter respectively of the cylindrical body 8b and of the circular section of the anti-roll bar 3. A longitudinal section of the fixing insert is therefore substantially “T” shaped. The fixing insert 8 is thus partially introduced into one end of the anti-roll bar 3. More precisely, the introduction of the fixing insert 8 into the end of the anti-roll bar 3 is done by inserting the cylindrical body 8b into the bar 3. The support head 8a blocks the introduction of the insert 8 into the bar 3, and bears against the entry of the end of the anti-roll bar 3. In other words, the support head 8a is positioned against the end of the anti-roll bar and in its axial extension. Thus, the fixing insert 8 and the end of the anti-roll bar 3 extend along the same axis A carrying the center of their respective circular section. The diameter of the cylindrical body 8b is sufficiently smaller than the diameter of the anti-roll bar 3 so that no contact takes place between the cylindrical body 8b and the anti-roll bar 3. The cylindrical body 8b therefore comprises an external surface 10 facing the internal walls of the end of the anti-roll bar 3. This external surface 10 defines an external part 10 of the fixing insert 8. The insert 8 is fixed to the anti-roll bar 3 by means of an electrical resistance weld 8c at the contact between the support head 8a of the insert 8 and the end of the anti-roll bar 3, as illustrated in [Fig.2]. The fixing insert 8 is blind. In other words, a cylindrical cavity 8d is made in the insert 8, this cylindrical cavity 8d passing through the insert 8 and opening at the support head 8a on the outside of the insert 8. The cavity 8d is on the other hand closed on its end opposite the support head 8a. The cavity 8d therefore constitutes a housing whose access is constituted by the part opening onto the support head 8a. The cavity 8d is cylindrical and is defined by internal walls 11 of the insert 8 of circular section and whose center is carried by the axis A. The fixing insert 8 therefore comprises an internal part 11 defined by the walls 11 of the cavity 8c, and an external part 10 defined by the external surface 10 of the cylindrical body 8b. The connecting member 9 is fixed to the first ball joint '7a of the connecting rod 6, and comprises a protective bellows 12, a clamping means 13 and a threaded end piece 14 aligned along the axis A, so that the connecting member 9 extends along the same axis A as the cavity 8d, the fixing insert 8 and the end of the anti-roll bar 3. The clamping means 13 comprises, for example, a hexagonal crown intended to serve as a grip for a clamping tool such as an adjustable wrench. The protective bellows 12 is arranged in a known manner around a material net 12a shown in dotted lines in [Fig. 2] and connecting the clamping means 13 to the ball joint 7a. In this way, the bellows 12 protects the ball joint 7a from an impact with the clamping tool when tightening the connecting member 9, and also protects the ball joint 7a from possible external aggressions such as liquids, sand or dust. The threaded end piece 14 extends from a surface of the clamping means 13 opposite the ball joint 7a and the protective bellows 12. The radial dimension of the clamping means 13 is greater than the diameter of the threaded end piece 14, so that the use of the clamping tool is facilitated and the risks of damage are reduced. The internal surface forming the internal part 11 of the fixing insert 8 is tapped with so that the threaded end piece 14 is configured to be inserted into the internal part of the insert 8 and cooperate with said tapping. The connecting member 9 is therefore configured to cooperate with the internal part 11 to secure the insert 8 to the ball joint 7a. The axial length of the threaded end piece 14 is substantially equal to the axial length of the internal part 11 of the fixing insert 8. When the ball joint 7a and the insert 8 are secured, the clamping means 13 comprises a surface in contact with the head 8a of the insert 8. Thus, the ball joint 7a of the connecting rod 6 is fixed to the anti-roll assembly 2, and more particularly to the anti-roll bar 3 by means of the connecting member 9 partially inserted into the fixing insert 8 which is secured in a free and hollow end of a lateral arm 3a of the anti-roll bar 3. The insert 8 is fixed to the anti-roll bar 3 solely by welding, so that it is the welding which absorbs all the forces and moments transmitted by the suspension system 4 and the corresponding wheel to the anti-roll assembly 2. These forces and moments result from alternating stresses of the swivel type, which can cause the weld or even the fixing insert 8 and / or the thread / tapping assembly to break. Furthermore, the threading / tapping system between the connecting member 9 and the internal part 10 of the fixing insert 8 is not sufficiently robust with regard to the stresses undergone, which can cause wear and unscrewing due to their alternation. Finally, since the tapping is very close to the welding zone, the heating required for welding can cause changes in the mechanical characteristics of the tapping, resulting in a malfunction of the assembly. The present invention therefore aims to avoid the aforementioned drawbacks and to propose a device for fixing one end of an anti-roll bar of a vehicle to a vehicle suspension system which is easy to manufacture, inexpensive and robust. The invention therefore relates to a device for fixing one end of an anti-roll bar of a vehicle to a suspension system of the vehicle, comprising a connecting rod intended to be connected to the suspension system and a means for fixing the connecting rod to the anti-roll bar, the connecting rod comprising one end equipped with a ball joint, the fixing means comprising a connecting member fixed to the ball joint and a fixing insert comprising a cylindrical body extending along an axis and a bearing head formed on one end of the cylindrical body, the bearing head resting against the end of the anti-roll bar and the body being inserted into the end of the anti-roll bar, the fixing insert comprising an internal part opening onto the bearing head and receiving a rod of the connecting member, the cylindrical body comprising an external part opposite the interior of the anti-roll bar. In the device according to the invention, the external part of the cylindrical body comprises at least one protrusion extending radially to be in contact with the interior of the anti-roll bar. This means that the stresses from the wheel and the vehicle's suspension system are no longer transmitted solely through the weld, but also through the protrusions of the mounting insert in contact with the anti-roll bar, thereby relieving the weld. Advantageously, the sum of the axial lengths of the at least one radial protrusion is less than half of the total axial length of the cylindrical body. Thus, the forces required to introduce the fixing insert into the anti-roll bar are reduced, while improving the robustness of the fixing device for absorbing the forces and stresses coming from the suspension system through contact between the protrusions and the bar. Advantageously, the internal part comprises a first portion of diameter D1 and axial length LI, a second portion of diameter D2 and axial length L2, and a third portion of diameter D3 and axial length L3, the second portion being axially positioned between the first portion and the third portion, the first portion comprising the opening opening of the internal part onto the support head, the diameters of the three portions being linked by the relationship: D3 <D2<D1] Advantageously, the first portion and the second portion are smooth, and the third portion is partially tapped, the tapping being arranged in axial contact with the second portion. Preferably, the rod of the connecting member comprises a first fraction of diameter D4 and length LA and a second fraction of diameter DS and length LS, the first fraction being arranged between the support head and the second fraction, the diameters of the two portions being linked by the relationship: D5 <D4 Advantageously, the first fraction is smooth, the second portion being shrunk onto the first fraction, the second fraction being threaded and cooperating with the tapping of the third portion of the fixing insert. In this way, the location of the thread and tapping allows to improve the lever arm and improve the robustness of the device. Advantageously, the respective axial lengths L5 and L2 of the second fraction and the second portions are linked by the following relation: L2 <L5 Preferably, the connecting member comprises a clamping means activatable using a clamping tool, the connecting member further comprising a first and a second protective base arranged on either side axially and in contact with the clamping means, the first base being arranged axially in contact and between the rod and the clamping means. Advantageously, the axial length LA of the first fraction and the respective axial lengths LI and L2 of the first and second portions are linked by the following relationship: L4<1.1+L2 The invention also relates to a vehicle comprising a wheel set comprising a first and a second wheel, the first wheel being associated with a first suspension system and the second wheel being associated with a second suspension system, the two suspension systems being connected to each other by means of an anti-roll bar of the vehicle, the anti-roll bar being fixed to the suspension systems by each of its ends by means of a fixing device as defined above. Brief description of the drawings Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example, and made with reference to the appended drawings in which: [Fig.1] illustrates a device for attaching a suspension system to the anti-roll bar of a vehicle according to the prior art; [Fig.2] illustrates a longitudinal sectional view of the fixing device of [Fig.1]; [Fig.3] illustrates a device for attaching a suspension system to the anti-roll bar of a vehicle according to the invention; and [Fig.4] illustrates a longitudinal sectional view of a fixing device of [Fig.3]. Detailed description of at least one embodiment [Fig. 3] therefore shows a partial perspective view of a motor vehicle 15 equipped with an anti-roll assembly 16 according to the invention. The anti-roll assembly 16 comprises a metal anti-roll bar 17, for example made of steel, substantially U-shaped and of circular section. The anti-roll bar 17 thus comprises two identical lateral arms 17a, and a central section 17b connecting the two lateral arms 17a by one of their ends. Each of the lateral arms 17a thus comprises an end linked to the central section 17b and an opposite hollow free end 17c, this free end 17c corresponding to one end of the anti-roll bar 17. Each of the opposite free ends 17c extends to an edge 17d formed by a lateral surface and comprising an inlet giving access to the interior of the free end, this interior being formed by an internal wall 17th. The anti-roll bar 17 is fixed to the chassis of the vehicle 15 by bearings 15a and 15b partially enclosing the central section 17b. The vehicle 15 comprises a suspension system 18 for the same set of front or rear wheels of the vehicle 15 associated with each of the wheels. The vehicle 15 therefore comprises a suspension system 18 for the left wheel and a suspension system 18 for the right wheel. Each suspension system 18 is connected to the anti-roll assembly 16 via a fixing device 19. More specifically, the fixing devices 19 each make it possible to connect a suspension system 18 to a hollow end 17c of a lateral arm 17a of the anti-roll bar 17. Subsequently, only one of the fixing devices 19 will be described, for example the fixing device 19 of the left wheel, the whole of what will be described being symmetrical and identical for the right side. Such a fixing device 19 is illustrated in partial longitudinal section in [Fig. 4]. The left hollow free end 17c of the anti-roll bar 17 is thus illustrated in [Fig. 4] and extends along a longitudinal axis B. The lateral surface forming the end edge 17d is thus orthogonal to the axis B. The fixing device 19 comprises a connecting rod 20 and a means 21 for fixing the connecting rod to the anti-roll bar 17. More precisely, the fixing means 21 is a means for fixing the connecting rod 20 to the hollow end 17c of a lateral arm 17a of the anti-roll bar 17. The connecting rod 20 is a metal rod comprising a first end formed by a first ball joint 21a and a second opposite end formed by a second ball joint 21b. The first ball joint 21a connects the connecting rod 20 to the anti-roll bar 17, and more precisely to the hollow end 17c of a lateral arm 17a of the anti-roll bar 17, while the second ball joint 21b connects the connecting rod 20 to the suspension system 18. The ball joints 21a and 21b thus allow the connecting rod 20 to be oriented according to the relative movement of the suspension system 18 with respect to the anti-roll bar 17. The fixing means 21 comprises a fixing insert 22 and a connecting member 23 of the connecting rod to the fixing insert illustrated in partial longitudinal section in [Fig.4]. The fixing insert 22 comprises a support head 22a and a cylindrical body 22b of substantially circular section and of diameter less than or equal to the diameter of the circular section of the anti-roll bar 17 defined between the opposite inner walls 17e of a plane orthogonal to the axis B of the anti-roll bar 17. The support head 22a constitutes one of the ends of the cylindrical body 22b and forms a collar of diameter greater than the diameter respectively of the cylindrical body 22b and of the circular section of the anti-roll bar 17. A longitudinal section of the fixing insert 22 therefore has a substantially “T” shape. The fixing insert 22 is thus partially introduced into the hollow end 17c of a lateral arm 17a of the anti-roll bar 17. More precisely, the introduction of the fixing insert 22 into the end 17c of the anti-roll bar 17 is done by inserting the cylindrical body 22b into the bar 17 via the end edge 17d. The bearing head 22a blocks the introduction of the insert 22 into the bar 17, and bears against the edge 17d of the end 17c of the anti-roll bar 17. In other words, the bearing head 22a is positioned against the edge 17d of the end 17c of the anti-roll bar 17 and in its axial extension. Thus, the fixing insert 22 and the hollow end 17c of the lateral arm 17b of the anti-roll bar 17 extend along the same axis B carrying the center of their respective circular sections. The cylindrical body 22b therefore comprises an external surface 24 facing the internal wall 17e of the end 17c of the anti-roll bar 17.This external surface 24 defines an external portion 24 of the fixing insert 22. The attachment of the insert 22 to the anti-roll bar 17 is done by an electrical resistance weld 22c at the contact between the support head 22a of the insert 22 and the edge 17d of the end 17c of the anti-roll bar 17, as illustrated in [Fig. 4]. The weld is therefore made at points located on a surface of the support head 22a opposite the end 17c of the anti-roll bar 3, and on the edge 17d of the end 17c. The external part 24 therefore has a circular section with a diameter smaller than the diameter of the circular section of the anti-roll bar 17 defined by the internal wall 17e. However, the external part 24 further comprises at least one radial protrusion 25. The at least one radial protrusion 25 is preferably annular, and extends radially sufficiently to establish contact with the internal wall 17e of the anti-roll bar 17. The at least one radial protrusion 25 therefore gives the cylindrical body 22b, punctually in its axial position, a circular section with a diameter equal to the diameter of the internal wall 17e of the anti-roll bar 17. Thus, the at least one radial protrusion 25 of the cylindrical body 22b constitutes for the fixing insert 22 at least one additional support point on the anti-roll bar 17, in addition to the weld. In this way, the forces and moments undergone by the anti-roll bar 17 and transmitted by the wheels and the suspension systems 18 are no longer entirely absorbed by the weld 22c, but also by the points of the bar 17 in contact with the at least one radial protrusion 25. The weld 22c is therefore protected, and the fixing device 19 gains in robustness. The at least one protrusion 25 is preferably positioned on the side of the external part 24 opposite the support head 22a in order to optimize the effectiveness of the lever arm. The example illustrated in [Fig.4] comprises a first protrusion 25a and a second protrusion 25b, the first protrusion 25a being arranged opposite the support head 22a, and the second protrusion 25b being arranged between the first protrusion 25a and the support head 22a. Preferably, the sum of the axial lengths of the at least one radial protrusion 25 is less than half the total length of the cylindrical body 22a. In this way, the fixing insert 22 is lightened, the forces necessary for inserting the fixing insert 22 into the anti-roll bar 17 are reduced while ensuring improved robustness. Finally, the at least one protrusion 25, that is to say in the example illustrated the protrusions 25a and 25b, also make it possible to ensure better centering of the fixing insert 22 in the end 17c of the anti-roll bar 17, so as to guarantee the coaxial nature along the axis B of the elements of the fixing device 19 according to the invention. In this way, the centering of the first ball joint 21a is improved. The fixing insert 22 is blind. In other words, a cylindrical cavity 22d is made in the insert 22, this cylindrical cavity 22d passing through the insert 22 and opening at the level of the support head 22a on the outside of the insert 22. The cavity 22d is on the other hand closed on its end opposite the support head 22a. The cavity 22d therefore constitutes a housing whose access is constituted by a part opening onto the support head 22a. The cavity 22d is cylindrical and is defined by an internal wall 26 of the insert 22 of circular section and whose center is carried by the axis B. The fixing insert 22 therefore comprises an internal part 26 defined by the internal wall 26 of the cavity 22d, and an external part 24 defined by the external surface 24 of the cylindrical body 22b. The internal part 26 comprises a first portion 26a of diameter D1 and axial length L1 along the axis B, a second portion 26b of diameter D2 and axial length L2 along the axis B and a third portion 26c of diameter D3 and axial length L3 along the axis B. The first portion 26a extends axially between the opening part of the cavity 22d on the support head 22a and the second portion 26b, located at an axial length L1 from the opening part of the cavity 22d. The third portion 26c extends from the closed end of the cavity 22d to the second portion 26b, located at an axial length L3 from said closed end of the cavity 22d. The second portion 26b is axially positioned and extends axially between the first portion 26a and the third portion 26b. The respective diameters D], D2, D3 of the first, second and third portions 26a, 26 and 26c are related by the relation: D3 < D2 < D1 The first and second portions 26a and 26b have smooth walls, while the third portion 26c is partially tapped. Indeed, the third portion 26c comprises a tapping extending axially from the second portion 26b to a point axially distant from the second portion 26b by a length less than L3, the remaining part of the third portion 26c comprising smooth walls. The connecting member 23 is fixed to the first ball joint 21a of the connecting rod 20, and comprises a protective bellows 27, a clamping means 28 and a rod 29 aligned along the axis B, so that the connecting member 23 extends along the same axis B as the cavity 224d, the fixing insert 22 and the end 17c of the anti-roll bar 17. The clamping means 28 comprises, for example, a hexagonal crown intended to serve as a grip for a clamping tool such as an adjustable wrench. The protective bellows 27 is arranged in a known manner around a material net 27a shown in dotted lines in [Fig. 4] connecting the clamping means 28 to the first ball joint 21a. In this way, the bellows 27 protects the ball joint 21a from an impact with the clamping tool when tightening the connecting member 23, and also protects the ball joint 21a from possible external aggressions such as liquids, sand or dust. The connecting member 23 further comprises a first base 30 and a second base 31 aligned along the axis B with the rod 29, the clamping means 28, and the protective bellows 27 associated with the material thread 27a. The first base 30 is arranged axially between and in contact with the clamping means 28 and the rod 29. The second base 31 is arranged axially between and in contact with the clamping means 28 and the protective bellows 27. The first base 30 comprises a surface 30a orthogonal to the plane axis B resting against the support head 22a, this surface 30a participating in the transmission of the forces and moments coming from the suspension system 18 to the insert 22. The second base 31 is symmetrical and identical to the first base with respect to the clamping means 28, the second base 31 comprising a surface 31a orthogonal to the plane axis B in contact with the protective bellows 27. The bases 30 and 31 have a radial dimension greater than the diameter of the clamping means 28, and thus make it possible to protect the elements of the fixing device 19 when using the clamping tool on the clamping means 28. In particular, the first base 30 protects a coating of the anti-roll bar 17 consisting of an organic protection against chemical and / or mechanical attacks coming from the external environment, such as an epoxy protection. The rod 29 extends from the surface 30a of the first base 30, the first base 30a resting against the bearing head 22a. The rod 29 has a circular section orthogonal to the axis B. The rod 29 comprises a first fraction 29a of diameter D4 and axial length LA along the axis B, and a second fraction 29b of diameter D5 and axial length LS along the axis B. The respective diameters D4 and D5 of the first and second fractions 29a and 29b are linked by the relation: DS < D4 The first fraction 29a is arranged axially between the clamping means 28 and the second fraction 29b, and more precisely between the first base 30 and the second fraction 29b, the second fraction 29b forming the end of the connecting member 23 opposite the support head 22a. The first fraction 29a is smooth while the second fraction 29b is threaded. The rod 29 is configured to be inserted into the internal part 26 of the insert 22 and to cooperate with the fixing insert 22. More precisely, the diameter DS of the second fraction 29b is substantially equal to the diameter D3 of the third portion 26c. In addition, the thread of the second fraction 29b is capable of cooperating with the tapping of the third portion 26c. Thus, the second fraction 29b is configured to cooperate with the third portion 26c for securing the fixing insert 22 with the connecting member 23. In addition, the axial length of the tapping of the third portion 26c is less than the axial length L3 of this third portion 26c, so that the third portion 26c comprises a smooth axial part. Furthermore, the diameter D4 of the first fraction 29a is substantially equal to the diameter D2 of the second portion 26b, greater than the diameter D3, and less than the diameter D1 of the first portion 26a. In this way, the second portion 26b is configured to be shrink-fitted onto the first fraction 29a when the rod 29 is inserted into the cavity 26 of the fixing insert 22. Thus, the tapping and the threading are less stressed in the absorption of external forces and moments, so as to avoid its breakage. The securing of the fixing insert 22 to the connecting member 23 is therefore done on the one hand by shrink-fitting the second portion 26b onto a part of the first fraction 29a and on the other hand by cooperation of the respective threading and tapping of the second fraction 29b and the third portion 26c.The support of the first base 30 on the support head 22a also constitutes a final means of securing the insert 22 to the connecting member 23, making it possible to relieve the threading / tapping. The respective axial lengths L5 and L2 of the second fraction 29b, of the first and second portions 26a and 26b, are connected by the following relation: 1L”2 <LS5 In this way, when the rod 29 of the connecting member 23 is inserted into the cavity 22d of the fixing insert 22, the thread of the second fraction 29b engages a few steps with the tapping of the third portion 26c before shrinking is possible. In this way, a sufficient length of thread is engaged in the tapping to resist the axial shrinking force without damaging the thread-tapping. Furthermore, the axial length of the rod 29, equal to the sum of the axial length L& of the first fraction and the axial length LS of the second threaded fraction 29b, is less than the axial length between the end of the support head 22a in contact with the first base 30 and the axial end of the tapping of the third portion 26c in contact with the smooth axial part of the third portion 26c, so that the thread does not stop at the bottom of the tapping. Finally, the axial length LA of the first fraction 29a and the respective axial lengths L1 and L2 of the first and second portions 26a and 26b are linked by the following relation: L4 <L1+L2 Thus, the connecting member 23 and the fixing insert 22 are configured so that the first base 30 is pressed against the support head 22a before the maximum possible hooping length is reached, that is to say before the first fraction 29a abuts against a surface orthogonal to the axis B of the third portion 26c. Furthermore, as a result, the area of the rod 29 between the first base 30 and the first thread of the thread of the second fraction 29b engaged with the tapping of the third portion 26c constitutes an elastic reserve of the assembly to prevent unscrewing when the stresses imposed on the assembly are very high. Finally, the position of the thread-tapping of the second fraction and third portion is relatively far from the welding point, so that the heating necessary for welding does not risk damaging the thread-tapping. In another embodiment, the connection between the fixing insert 22 and the end 17c of the anti-roll bar 17 is made by crimping between the contact surfaces, so as to avoid welding. For example, the crimping can be made by deforming the anti-roll bar 17 axially between the two protrusions 25a and 25b. In yet another embodiment, the hooping can be eliminated, without modifying the characteristics relating to the length LA, so as to reduce manufacturing costs for applications having a lower level of stress.
Claims
Claims
1. Device (19) for fixing one end (17c) of an anti-roll bar (17) of a vehicle (15) to a suspension system (18) of the vehicle, comprising a connecting rod (20) intended to be connected to the system of suspension (18) and a means (21) for fixing the connecting rod (20) to the anti-roll bar (17), the connecting rod (20) having one end equipped with a ball joint (21a), the fixing means (21) comprising a connecting member (23) fixed to the ball joint (21a) and a fixing insert (22) comprising a cylindrical body (22b) extending along an axis (B) and a support head (22a) formed on one end of the cylindrical body (22b), the support head (22a) resting against the end (17c) of the anti-bar cant (17) and the cylindrical body (22b) being inserted into the end (17c) of the anti-roll bar (17), the fixing insert (22) comprising an internal part (26) opening onto the support head (22a) and receiving a rod (29) of the connecting member (23), the cylindrical body (22b) comprising an external part (24) facing the interior (17e) of the anti-roll bar (17), characterized in that the external part (24) of the cylindrical body (22a) comprises at least one protrusion (25, 25a, 25b) extending radially to be in contact with the interior (17e) of the anti-roll bar (17).
2. A fixing device according to claim 1, wherein the sum of the axial lengths of at least one radial outgrowth (25, 25a, 25b) is less than half of the total axial length of the cy- body lindric (25b).
3. A fastening device according to one of claims 1 or 2, wherein the internal part (26) comprises a first portion (26a) of diameter D1 and axial length L1, a second portion (26b) of diameter D2 and axial length L2, and a third portion (26c) of diameter D3 and axial length L3, the second portion (26b) being axially positioned between the first portion (26a) and the third portion (26c), the first portion (26a) comprising the opening leading to the internal part (26) on the support head (22a), the diameters of the three portions (26a, 26b, 26c) being linked by the relation: D3 <D2<D1
4. A fastening device according to claim 3, wherein the first portion (26a) and the second portion (26b) are smooth, and the third portion (26c) is partially tapped, the tapping being arranged at axial contact of the second portion (26b).
5. A fixing device according to any one of claims | to 4, wherein the rod (29) of the connecting member (23) comprises a first fraction (29a) of diameter D4 and length LA and a second fraction (29b) of diameter D5 and length LS, the first fraction (29a) being arranged between the support head (22a) and the second fraction (29b), the diameters of the two fractions (29a, 29b) being linked by the relationship: DS < D4
6. Device according to claims 4 and 5, in which the first fraction (29a) is smooth, the second portion (26b) being fretted on the first fraction (29a), the second fraction (29b) being threaded and cooperating with the tapping of the third portion (26c) of the insert of fixing (22).
7. A fastening device according to claim 6, wherein the lengths respective LS and L2 axial lines of the second fraction (29b) and of the second portion (26b) are connected by the following relation: L2 <L5
8. A fixing device according to claim 7, wherein the member of connector (23) comprises a clamping means (28) activatable using a clamping tool, the connecting member (23) further comprising a first and second protective bases (30 and 31) arranged in axial side and in contact with the clamping means (28), the first base (30) being arranged axially in contact with and between the rod (29) and the clamping means (28).
9. A fastening device according to claim 8, wherein the length axial LA of the first fraction (29a) and the axial lengths res- L1 and L2 perspectives of the first and second portions (26a and 26b) are connected by the following relationship: ZL4< L]+Z?
10. Vehicle (15) comprising a wheel set comprising a first and a second wheel, the first wheel being associated with a first suspension system (18) and the second wheel being associated with a second suspension system (18), both suspension systems (18) being connected to each other by means of an anti-bar cant (17) of the vehicle (15), the anti-roll bar (17) being fixed to the suspension systems (18) at each of its ends (17c) by a fixing device according to any one of claims 1 to 9.