Multi-link suspension

Abstract

The multi-link suspension provided by the present application comprises: a knuckle comprising a main body and an extension arm; the transverse control arm assembly comprises an upper control arm, the upper control arm and the extension arm are oppositely arranged, the upper control arm is located above the extension arm, the first end of the upper control arm is rotationally connected to the main body, and the second end of the upper control arm is used for being rotationally connected with an auxiliary frame; the brake swing rod is obliquely arranged relative to the vertical direction, and the two ends of the brake swing rod are rotationally and obliquely connected between the upper control arm and the extension arm; the first end of the trailing arm is rotationally connected to the steering knuckle, and the second end of the trailing arm is used for being rotationally connected with a longitudinal beam of a vehicle body. Rigid support needed by braking is guaranteed, the longitudinal flexibility can be properly increased, and the comfort of a suspension system for resisting impact from the front direction and the rear direction of a vehicle body is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of vehicle suspensions and relates to a multi-link suspension. BACKGROUND

[0002] A suspension is a connecting structure between a vehicle body and a wheel and transmits force and torque between the vehicle body and the wheel.

[0003] Traditional suspensions include an "E"-type multi-link suspension, an "H"-type multi-link suspension, a five-link suspension, a double wishbone suspension and the like, and the suspensions are all provided with a trailing arm connected with a vehicle body longitudinal beam. On the one hand, the trailing arm is required to have a certain longitudinal flexibility to ensure impact comfort; on the other hand, when the trailing arm performs a braking condition, sufficient rigidity needs to be provided to rapidly transmit a braking torque.

[0004] Therefore, it is necessary to provide a multi-link suspension to improve the coupling performance of longitudinal flexibility and braking torque rigidity. SUMMARY

[0005] The application provides a multi-link suspension to solve the problems in the prior art, which can not only ensure the rigid support required by braking but also appropriately increase longitudinal flexibility and improve the comfort of the suspension system against impacts from the front and rear directions of the vehicle body.

[0006] The multi-link suspension provided by the application comprises a knuckle including a main body and an extension arm, a transverse control arm assembly including an upper control arm, the upper control arm being oppositely arranged with the extension arm and located above the extension arm, a first end of the upper control arm being rotationally connected to the main body, and a second end of the upper control arm being used for rotationally connecting with a subframe, a brake swing lever being obliquely arranged relative to the vertical direction, two ends of the brake swing lever being rotationally and obliquely connected between the upper control arm and the extension arm, and a trailing arm, a first end of the trailing arm being rotationally connected to the knuckle, and a second end of the trailing arm being used for rotationally connecting with a vehicle body longitudinal beam.

[0007] Optionally, the two ends of the brake swing lever are rotationally connected with the upper control arm and the extension arm one by one through a first brake bushing and a second brake bushing, respectively; the first brake bushing has a rigidity value k1, the second brake bushing has a rigidity value k2, 15000 N / mm≤k1≤30000 N / mm, and 15000 N / mm≤k2≤30000 N / mm.

[0008] Optionally, the first brake bushing is connected to the bottom of the upper control arm, and the second brake bushing is connected to the top of the extension arm or the end of the extension arm; a guide bracket is arranged on the main body and located between the extension arm and the upper control arm, a guide waist hole is formed in the guide bracket and extends along a direction perpendicular to the rotation axis of the brake swing rod, and the brake swing rod passes through the guide waist hole and is in clearance fit with the two side walls along the length direction of the guide waist hole.

[0009] Optionally, a first brake lug is mounted on the bottom of the upper control arm, and the first brake bushing is rotatably mounted on the first brake lug; a support cylinder is mounted on the extension arm, and the second brake bushing comprises a second brake lug which is rotatably mounted on the outside of the support cylinder.

[0010] Optionally, the projection of the first brake bushing in the vertical direction is located between the second brake bushing and the main body.

[0011] Optionally, the first end of the trailing arm is connected with a first trailing bushing, the first trailing bushing is rotatably mounted on the knuckle, the second end of the trailing arm is connected with a second trailing bushing, the second trailing bushing is used for rotatably connecting with the vehicle body longitudinal beam, the stiffness value of the first trailing bushing is k3, the stiffness value of the second trailing bushing is k4, 300 N / mm≤k3≤600 N / mm, and 300 N / mm≤k4≤600 N / mm.

[0012] Optionally, the transverse control arm assembly further comprises an adjusting link and a spring link which are both located below the upper control arm and are oppositely arranged with the upper control arm; the first end of the adjusting link is rotatably connected to the knuckle, and the second end is used for rotatably connecting with the subframe; the first end of the spring link is rotatably connected to the knuckle, and the second end is used for rotatably connecting with the subframe.

[0013] Optionally, the angle between the trailing arm and the length direction of the vehicle body is α, and 5°≤α≤20°.

[0014] Optionally, the length of the brake swing rod is adjustably arranged.

[0015] Optionally, the upper control arm is provided with a cavity portion corresponding to the position of the brake swing rod, and an energy-absorbing material is arranged in the cavity portion.

[0016] The above technical scheme has the following beneficial effects: The multi-link suspension provided by the application defines a new and efficient braking force transmission path by adding a vertically inclined brake swing link between the upper control arm and the extension arm of the knuckle. During braking, the vertically inclined brake swing link can provide sufficient support to ensure that the braking force is transmitted to the upper control arm through the tire, the extension arm of the knuckle, the brake swing link, and then shared by the two end bushings of the upper control arm; the stiffness of the two ends of the drag link connected with the knuckle and the vehicle body longitudinal beam can be reduced, the longitudinal flexibility is appropriately increased, and the comfort of the suspension system against impact from the front and rear directions of the vehicle body is improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] The preferred embodiments of the application will be described in detail below with the help of the accompanying drawings, which are intended to help understand the purposes and advantages of the application.

[0018] Figure 1 The structural schematic diagram of the multi-link suspension provided by the optional embodiments of the application is shown.

[0019] Figure 2 The structural schematic diagram of the upper control arm, the brake swing link and the drag link at the connection provided by the optional embodiments of the application is shown.

[0020] Explanation of reference signs: 1-knuckle, 10-main body, 11-extension arm, 110-support cylinder, 2-transverse control arm assembly, 20-upper control arm, 200-first brake ear seat, 21-adjusting link, 22-spring link, 3-brake swing link, 30-first brake bushing, 31-second brake bushing, 310-second brake ear seat, 4-drag link, 40-first drag bushing, 41-second drag bushing. DETAILED DESCRIPTION

[0021] The technical solutions of the application will be described in further detail below by way of examples and in combination with the accompanying drawings. In the present specification, the orientation terms such as up, down, left, right, front, back, front face, back face, top, bottom and the like are defined with respect to the configuration shown in the drawings, and the words "inner" and "outer" refer to the direction towards or away from the geometric center of a particular component, which are relative concepts, and thus can change accordingly depending on the different positions and different use states. Therefore, these or other orientation terms should not be interpreted as restrictive terms.

[0022] The multi-link suspension provided by the application includes a knuckle 1, a transverse control arm assembly 2, a brake swing link 3 and a drag link 4.

[0023] Please refer to Figure 1The steering knuckle 1 includes a body 10 and an extension arm 11. The steering knuckle 1 is the core load-bearing and moving component of the suspension, and is usually made of ductile iron or aluminum alloy. The body 10 is used to install wheel-related components such as wheel hub bearings. The extension arm 11 extends from one side of the body 10 and provides a connection fulcrum for the brake lever 3 below the upper control arm 20.

[0024] The lateral control arm assembly 2 includes an upper control arm 20, which is positioned opposite and above the extension arm 11. The first end of the upper control arm 20 is rotatably connected to the main body 10, and the second end is rotatably connected to the subframe. The lateral control arm assembly 2 transmits lateral loads between the chassis and the vehicle body and controls the wheel alignment surfaces. The first end of the upper control arm 20 is rotatably connected to the upper part of the main body 10 via a ball joint or bushing, and the second end of the upper control arm 20 is connected to the subframe via a ball joint or bushing. The upper control arm 20 is configured to be horizontal or approximately horizontal.

[0025] In the side view of the vehicle, the brake lever 3 is inclined relative to the vertical direction, and its two ends are rotatably inclined between the upper control arm 20 and the extension arm 11. Please refer to... Figure 2 The brake lever 3 forms a stable support structure with the upper control arm 20 and the extension arm 11. During braking, the braking force pushes the steering knuckle 1, which tends to move backward relative to the vehicle body. This force pulls the brake lever 3 through the extension arm 11, and the brake lever 3 converts the pulling force into a pushing or pulling force on the upper control arm 20, thereby efficiently distributing the longitudinal force to the connection points at both ends of the upper control arm 20.

[0026] The trailing arm 4 has its first end rotatably connected to the steering knuckle 1, and its second end rotatably connected to the vehicle body longitudinal beam. The trailing arm 4 provides the main longitudinal constraint and bears a portion of the driving force. During braking, due to the introduction of the brake lever 3, the longitudinal force borne by the trailing arm 4 is diverted, and its deformation is reduced, thereby helping to maintain the stability of the wheel alignment parameters.

[0027] In this embodiment, a new, efficient braking force transmission path is defined by adding a vertically inclined brake lever 3 between the upper control arm 20 and the extension arm 11 of the steering knuckle 1. During braking, the vertically inclined brake lever 3 can provide sufficient support to ensure that the braking force is transmitted to the upper control arm 20 through the tire, the extension arm 11 of the steering knuckle 1, and the brake lever 3, and then distributed between the two ends of the upper control arm 20. This reduces the stiffness of the trailing arm 4 at the ends connected to the steering knuckle 1 and the vehicle body longitudinal beam, appropriately increases longitudinal flexibility, and improves the comfort of the suspension system against impacts from the front and rear directions of the vehicle body.

[0028] In an optional embodiment, the two ends of the brake lever 3 are rotatably connected to the upper control arm 20 and the extension arm 11 respectively via a first brake bushing 30 and a second brake bushing 31. The stiffness value of the first brake bushing 30 is k1, and the stiffness value of the second brake bushing 31 is k2, where 15000N / mm≤k1≤30000N / mm and 15000N / mm≤k2≤30000N / mm. Both the first brake bushing 30 and the second brake bushing 31 are configured with high stiffness values, which can ensure that the elastic deformation of the connection point of the brake lever 3 is controlled within a very small range when transmitting braking force, thus ensuring the directness and efficiency of braking force transmission and avoiding sluggish braking response due to excessively soft bushings.

[0029] Furthermore, the first brake bushing 30 and the second brake bushing 31 can be reinforced bushings with internal wedge-shaped or limiting structures. Both the first brake bushing 30 and the second brake bushing 31 can be composed of an inner sleeve, an outer sleeve, and a rubber elastomer in between, and are connected to the connectors at the ends of the brake lever 3 and the corresponding mounting seats on the upper control arm 20 and the extension arm 11 respectively by interference fit or bolt tightening.

[0030] In an optional embodiment, the first brake bushing 30 is connected to the bottom of the upper control arm 20, and the second brake bushing 31 is connected to the top or end of the extension arm 11. A guide bracket is provided on the main body 10, located between the extension arm 11 and the upper control arm 20. The guide bracket has a guide waist hole extending perpendicular to the rotation axis of the brake lever 3. The brake lever 3 passes through the guide waist hole and is clearance-fitted with the two side walls of the guide waist hole along its length. This embodiment of the application allows the brake lever 3 to abut against the upper control arm 20 and the extension arm 11 in vertical space, forming a stable vertical support. Figure 2 The diagram shows the second brake bushing 31 connected to the end of the extension arm 11. The second brake bushing 31 can also be connected to other parts of the top of the extension arm 11. The guide bracket can be made of engineering plastic. The two side walls arranged opposite each other along the length direction on the guide hole can limit the brake lever 3, ensuring that the brake lever 3 swings only in the designed direction during movement. This provides longitudinal protection and limitation for the brake lever, avoiding longitudinal deformation caused by longitudinal force, and is particularly suitable for complex road conditions.

[0031] In an optional embodiment, a first brake lug 200 is mounted on the bottom of the upper control arm 20, and a first brake bushing 30 is rotatably mounted on the first brake lug 200; a support cylinder 110 is mounted on the extension arm 11, and the second brake bushing 31 includes a second brake lug 310, which is rotatably mounted on the outside of the support cylinder 110. The first brake lug 200 can be formed on the bottom of the upper control arm 20 by welding or integral casting, and the first brake lug 200 has a mounting hole perpendicular to the length direction of the upper control arm 20, into which the first brake bushing 30 is pressed. The second brake bushing 31 is connected to the top or end of the extension arm 11. Figure 2 As shown, a support cylinder 110 can be provided at the end of the extension arm 11. The second brake bushing 31 can be integrated into an assembly with a second brake lug 310. The second brake lug 310 is rotatably fitted onto the outside of the support cylinder 110 via a horizontal pin or bolt, thereby allowing the second brake bushing 31 to rotate slightly around the vehicle's lateral axis. The rotatable connection design of the first brake lug 200 and the second brake lug 310, especially the fact that the second brake bushing 31 can rotate around the support cylinder 110, allows the brake lever 3 to swing freely with the suspension during vehicle operation, avoiding motion interference. At the same time, it ensures that the first brake bushing 30 and the second brake bushing 31 mainly bear tensile and compressive forces rather than bending moments, thus extending their service life.

[0032] In an optional embodiment, the vertical projection of the first brake bushing 30 is located between the second brake bushing 31 and the body 10. The vertical projection refers to the projection viewed vertically downwards from directly above, such as... Figure 2 As shown, in this embodiment of the application, the force line of the brake lever 3 is inclined at the top toward the body 10 of the steering knuckle 1, which is beneficial for generating anti-nodding torque.

[0033] Furthermore, both the first brake bushing 30 and / or the second brake bushing 31 are internally equipped with fiber optic grating sensors or piezoelectric ceramic sensors that are connected to the control communication. These sensors are used to monitor in real time the tensile, compressive, shear, and temperature forces experienced by the first brake bushing 30 and / or the second brake bushing 31 during vehicle operation. The controller in this embodiment can be located on the vehicle chassis or in the vehicle's passenger compartment. Based on the force data of the first brake bushing 30 and / or the second brake bushing 31, the controller can predict its fatigue life, enabling predictive maintenance and reminding the user to replace the bushing before its performance deteriorates.

[0034] In an optional embodiment, a first towing arm 4 is connected to a first towing bushing 40, which is rotatably mounted on the steering knuckle 1; a second towing arm 4 is connected to a second towing bushing 41, which is rotatably connected to the vehicle body longitudinal beam; the stiffness value of the first towing bushing 40 is k3, and the stiffness value of the second towing bushing 41 is k4, where 300N / mm≤k3≤600N / mm and 300N / mm≤k4≤600N / mm. In this embodiment, the stiffness of the first trailing bushing 40 and the second trailing bushing 41 is much lower than that of the first brake bushing 30 and the second brake bushing 31, which has the following beneficial effects: First, under normal driving and driving conditions, the softer trailing bushing can effectively filter longitudinal impacts and vibrations transmitted from the road surface, improving ride comfort (NVH performance); Second, under braking conditions, since the high-stiffness brake lever 3 serves as the main force transmission path, the degrees of freedom of the first trailing bushing 40 and the second trailing bushing 41 are further released, and the trailing arm 4 and its softer first trailing bushing 40 and the second trailing bushing 41 can undergo moderate and controllable elastic deformation, which helps to further reduce the braking impact and make the braking process smoother.

[0035] Furthermore, the first towing bushing 40 is press-fitted into the metal tube at the front end of the towing arm 4 and connected to the steering knuckle 1 by a through bolt. The second towing bushing 41 has a similar structure, being press-fitted into the metal tube at the rear end of the towing arm 4 and connected to the mounting bracket on the vehicle body longitudinal beam by bolts.

[0036] Furthermore, due to the braking torque transmission effect of the brake lever 3, the connection point between the trailing arm 4 and the vehicle body longitudinal beam can be arranged higher, which is conducive to further improving ride comfort.

[0037] In an optional embodiment, the lateral control arm assembly 2 further includes an adjusting link 21 and a spring link 22, both located below and opposite to the upper control arm 20. The first end of the adjusting link 21 is rotatably connected to the steering knuckle 1, and the second end is rotatably connected to the subframe. The first end of the spring link 22 is rotatably connected to the steering knuckle 1, and the second end is rotatably connected to the subframe. The adjusting link 21 and the spring link 22, together with the upper control arm 20, constitute the suspension linkage structure, used to control parameters such as camber and toe angles during wheel movement. The spring link 22 is the main component for transmitting and buffering vertical loads; it is typically equipped with a vibration damping pad for mounting a coil spring, and the other end of the spring is connected to a corresponding structure in the body-in-white. The length of the adjusting link 21 is usually fine-tunable, used to set and correct the wheel toe angle.

[0038] In an optional embodiment, the angle between the trailing arm 4 and the vehicle length direction is α, where 5°≤α≤20°. This embodiment sets the angle between the trailing arm 4 and the vehicle length direction within a small range, allowing the trailing arm 4 to be arranged more closely to a pure longitudinal direction. This makes it more efficient and its deformation more controllable when bearing the remaining longitudinal force after it has been diverted. While the lateral constraint component it provides is smaller, it is easier to design and match using the upper control arm 20, adjusting link 21, and spring link 22, thereby optimizing the coupling between lateral stiffness and longitudinal flexibility of the suspension.

[0039] In one optional embodiment, the length of the brake lever 3 is adjustable, which allows for greater ease of assembly and adjustment of the suspension. During vehicle production or after-sales maintenance, the braking posture can be precisely set by finely adjusting the length of the lever 3. Simultaneously, fine-tuning the length can also slightly alter the initial preload or angle of the brake lever 3, thereby finely matching the initial braking feel and vehicle posture to different vehicle models or user preferences.

[0040] Optionally, the brake lever 3 is mainly composed of a hollow tube, with a threaded adjustment part at its first end. This end is connected to the outer sleeve of the first brake bushing 30 via a threaded connector. By rotating the connector, the effective distance between the hinge points at both ends of the brake lever 3 can be changed. After adjustment, the lock nut 35 is used to lock it in place to prevent loosening. The preferred adjustment range for the length of the brake lever 3 is ±5mm to ±15mm.

[0041] In an optional embodiment, the upper control arm 20 has a cavity corresponding to the position of the brake lever 3, and the cavity contains energy-absorbing material. The cavity and the energy-absorbing material disposed therein form a damping and vibration reduction module in a local area of ​​the upper control arm 20. The energy-absorbing material can convert the mechanical energy of the structural vibration transmitted to this location into heat energy and dissipate it, thereby effectively attenuating high-frequency vibration, significantly improving NVH performance during braking, and eliminating or reducing possible noise.

[0042] Furthermore, the cavity may be part of a closed box-shaped structure formed by the upper plate, lower plate, and side walls of the upper control arm 20, located directly above the first brake lug 200. The energy-absorbing material may be porous polyurethane foam, asphalt-based damping film, or other polymer damping materials.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A multi-link suspension, characterized in that, include: Steering knuckle, including body and extension arm; A lateral control arm assembly includes an upper control arm, which is disposed opposite to and above the extension arm. A first end of the upper control arm is rotatably connected to the main body, and a second end is rotatably connected to the subframe. The brake lever is inclined relative to the vertical direction, and its two ends are rotatably inclined between the upper control arm and the extension arm; The towing arm has a first end rotatably connected to the steering knuckle and a second end rotatably connected to the vehicle body longitudinal beam.

2. The multi-link suspension according to claim 1, characterized in that, The two ends of the brake lever are rotatably connected to the upper control arm and the extension arm respectively through the first brake bushing and the second brake bushing. The stiffness value of the first brake bushing is k1, and the stiffness value of the second brake bushing is k2, where 15000N / mm≤k1≤30000N / mm and 15000N / mm≤k2≤30000N / mm.

3. The multi-link suspension according to claim 2, characterized in that, The first brake bushing is connected to the bottom of the upper control arm, and the second brake bushing is connected to the top of the extension arm or the end of the extension arm; The main body is provided with a guide bracket, which is located between the extension arm and the upper control arm. The guide bracket has a guide waist hole, which extends along the rotation axis perpendicular to the brake swing rod. The brake swing rod passes through the guide waist hole and is clearance-fitted with the two side walls of the guide waist hole along its length.

4. The multi-link suspension according to claim 3, characterized in that, The bottom of the upper control arm is equipped with a first brake lug, and the first brake bushing is rotatably mounted on the first brake lug. A support cylinder is mounted on the extension arm, and the second brake bushing includes a second brake lug, which is rotatably mounted on the outside of the support cylinder.

5. The multi-link suspension according to claim 2, characterized in that, The vertical projection of the first brake bushing is located between the second brake bushing and the main body.

6. The multi-link suspension according to claim 1, characterized in that, The first end of the trailing arm is connected to a first trailing bushing, which is rotatably mounted on the steering knuckle. The second end of the trailing arm is connected to a second trailing bushing, which is used to rotatably connect with the longitudinal beam of the vehicle body. The stiffness value of the first drag bushing is k3, and the stiffness value of the second drag bushing is k4, where 300N / mm≤k3≤600N / mm and 300N / mm≤k4≤600N / mm.

7. The multi-link suspension according to any one of claims 1-6, characterized in that, The lateral control arm assembly also includes adjusting links and spring links, both located below the upper control arm and disposed opposite to the upper control arm; The first end of the adjusting linkage is rotatably connected to the steering knuckle, and the second end is rotatably connected to the subframe. The first end of the spring link is rotatably connected to the steering knuckle, and the second end is rotatably connected to the subframe.

8. The multi-link suspension according to any one of claims 1-6, characterized in that, The angle between the towing arm and the length direction of the vehicle body is α, where 5°≤α≤20°.

9. The multi-link suspension according to any one of claims 1-6, characterized in that, The length of the brake lever is adjustable.

10. The multi-link suspension according to any one of claims 1-6, characterized in that, The upper control arm has a cavity corresponding to the position of the brake lever, and the cavity is filled with energy-absorbing material.

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