Transverse torsion bar spring for motor vehicle suspension

Abstract

A transverse torsion bar spring for a motor vehicle suspension comprises a torsion bar extending transversely, the middle position of the torsion bar is fixedly connected with a middle rocker arm assembly in the circumferential direction, the two ends of the torsion bar are fixedly connected with side rocker arm assemblies in the circumferential direction respectively, and the transverse torsion bar spring of an E-shaped structure for axially positioning the torsion bar is formed. The middle rocker arm assembly comprises a middle rocker arm and a middle adjusting rod, one end of the middle rocker arm is circumferentially and fixedly connected to the middle of the torsion bar, the other end of the middle rocker arm is fixedly connected to the upper end of the middle adjusting rod, the lower end of the middle adjusting rod extends into a longitudinal strip-shaped hole formed in the frame cross beam or the auxiliary frame cross beam, and the middle adjusting rod is prevented from retreating from the strip-shaped hole through a limiting device. The side rocker arm assembly comprises a side rocker arm and a side adjusting rod, one ends of the left rocker arm and the right rocker arm are circumferentially fixed to the two ends of the torsion rod respectively, the other ends of the left rocker arm and the right rocker arm are movably connected with the upper ends of the left adjusting rod and the right adjusting rod respectively through ball joints, and the lower ends of the left adjusting rod and the right adjusting rod are fixedly connected with the left lower swing arm and the right lower swing arm or the left shock absorber cylinder and the right shock absorber cylinder respectively.

Description

Technical Field

[0001] The invention relates to the field of motor vehicle suspension, in particular to a transverse torsion bar spring used for motor vehicle suspension. Background Art

[0002] The intelligent transformation of urban terminal delivery is accelerating, and the large-scale application of low-speed unmanned logistics vehicles in emerging scenarios such as instant retail and community group buying has entered an industrial explosion period. Authoritative monitoring data shows that since 2023, the average daily order volume of unmanned delivery vehicles of leading companies has exceeded 3 million. The exponential growth of business scale has put forward dual technical indicators for vehicle transportation systems: it is necessary to achieve a loading efficiency of ≥85% of the cargo box volume ratio, and to strictly control the ground clearance of the chassis within 180mm to meet the barrier-free loading and unloading needs of high-frequency urban delivery scenarios.

[0003] The structural limitations of traditional suspension systems are becoming increasingly prominent. Currently, the suspension elastic elements of box-type logistics vehicles mainly use coil springs or torsion bar spring structures.

[0004] The coil spring itself has no shock-absorbing effect, so a shock absorber must be installed separately in the coil spring suspension. In addition, the coil spring can only withstand vertical loads, so a guide mechanism must be installed to transmit various forces and moments other than the vertical force. Therefore, the use of coil springs as suspension elastic elements has the following technical bottlenecks: the complex mechanical structure causes the effective loading space of the cargo box to be occupied by more than 12%; the excessively high proportion of unsprung mass seriously restricts the dynamic response performance of the vehicle; there is a systematic conflict between the traditional suspension stroke parameters and the low frame structure design, which makes it difficult to achieve a balance between the vehicle's passability and loading efficiency.

[0005] CN102756627B discloses a spring structure for a wheel suspension of a motor vehicle, which is a transverse torsion bar spring. However, in the technical solution of CN102756627B, components such as a torsion adjuster and a hollow cylindrical connecting bracket are provided. This structure, on the one hand, has a high production cost and complex subsequent maintenance, which is not conducive to the large-scale use of low-speed unmanned logistics vehicles. On the other hand, more components will greatly encroach on the effective loading space of the cargo box, making it difficult to meet distribution needs. Summary of the invention

[0006] The object of the present invention is to provide a transverse torsion bar spring for a motor vehicle suspension in view of the corresponding deficiencies in the prior art, comprising a transversely extending torsion bar, wherein the middle position of the torsion bar is circumferentially fixedly connected to an intermediate rocker arm assembly, and the two ends of the torsion bar are respectively circumferentially fixedly connected to side rocker arm assemblies, forming an E-shaped transverse torsion bar spring for axially positioning the torsion bar, thereby achieving space optimization and adjustment of vehicle body height and suspension stiffness at a relatively low cost.

[0007] The objective of the present invention is achieved by adopting the following scheme: A transverse torsion bar spring for a motor vehicle suspension, comprising a transversely extending torsion bar, wherein the middle position of the torsion bar is circumferentially fixedly connected to an intermediate rocker arm assembly, and both ends of the torsion bar are circumferentially fixedly connected to side rocker arm assemblies, forming an E-shaped transverse torsion bar spring for axially positioning the torsion bar; The intermediate rocker arm assembly comprises an intermediate rocker arm and an intermediate adjustment rod, one end of the intermediate rocker arm is circumferentially fixedly connected to the middle of the torsion bar, and the other end is fixedly connected to the upper end of the intermediate adjustment rod, the lower end of the intermediate adjustment rod extends into a longitudinal strip hole opened on the frame crossbeam or the sub-frame crossbeam, and a limiting device is used to prevent the intermediate adjustment rod from exiting the strip hole; The side rocker arm assembly includes a side rocker arm and a side adjusting rod. One end of the left and right rocker arms are circumferentially fixed on the two ends of the torsion bar respectively, and the other ends of the left and right rocker arms are movably connected to the upper ends of the left and right adjusting rods respectively through ball joints. The lower ends of the left and right adjusting rods are fixedly connected to the left and right lower swing arms or the left and right shock absorber cylinders respectively.

[0008] Preferably, the torsion bar consists of a left torsion bar and a right torsion bar, both ends of the left and right torsion bars are provided with external splines, one end of the middle rocker arm is provided with an internal spline sleeve, the internal spline sleeve is provided with a partition wall, and one end of the side rocker arm is provided with an internal spline blind hole tube, the two ends of the left and right torsion bars are respectively meshed with the internal spline sleeve and the internal spline blind hole tube, and abut against the bottom of the hole and the partition wall of the internal spline blind hole tube to achieve axial positioning of the torsion bar.

[0009] Preferably, the torsion bar is provided with external splines in the middle position and at both ends, the middle rocker arm is provided with an internal spline sleeve at one end, the internal spline sleeve is meshed with the external splines in the middle of the torsion bar, the side rocker arm is provided with an internal spline blind hole tube at one end, the internal spline blind hole tube is meshed with the external splines at both ends of the torsion bar, and the two ends of the torsion bar abut against the bottom of the internal spline blind hole tube to achieve axial positioning of the torsion bar.

[0010] Preferably, the intermediate adjustment rod is an external threaded rod, an internal threaded hole is formed at one end of the intermediate rocker arm, and the upper end of the intermediate adjustment rod is threadedly engaged in the internal threaded hole of the intermediate rocker arm; Alternatively, the intermediate adjusting rod is an externally threaded rod, a through hole is provided at one end of the intermediate rocker arm, the intermediate adjusting rod passes through the through hole of the intermediate rocker arm, and the intermediate rocker arm is fixedly connected to the upper end of the intermediate adjusting rod by bolts.

[0011] Preferably, the intermediate adjustment rod is an externally threaded rod, the limiting device is a limiting nut, the lower end of the intermediate adjustment rod extends into a longitudinal strip hole opened on the frame crossbeam or the sub-frame crossbeam, and is threadedly engaged with a limiting nut to prevent the intermediate adjustment rod from exiting the strip hole.

[0012] Preferably, the ball hinge joint comprises a ball pin and a ball seat, the transversely extending ball pin is fixedly arranged at one end of the side rocker arm, and the ball seat is fixedly connected to the upper end of the side adjustment rod.

[0013] Preferably, the side adjustment rod is an external threaded rod, the radial extension portion of the ball seat is provided with an internal threaded hole, and the upper end of the side adjustment rod is threadedly fitted in the internal threaded hole of the ball seat; Alternatively, the side adjustment rod is an externally threaded rod, a through hole is provided on the radial extension portion of the ball seat, the side adjustment rod passes through the through hole of the ball seat, and the ball seat is fixedly connected to the upper end of the side adjustment rod by bolts.

[0014] Preferably, a slider is provided on the middle adjusting rod, the upper end surface of the slider is a circular arc sliding surface, and the lower end surface is abutted against the limit device, and an arc cover plate cooperating with the circular arc sliding surface is provided on the frame crossbeam or the sub-frame crossbeam, and a strip hole is opened on the arc cover plate to facilitate the longitudinal swing of the middle adjusting rod.

[0015] The beneficial effects of the present invention are as follows: 1. Structural integration and space optimization. The E-shaped transverse torsion bar spring structure integrates the middle rocker arm assembly, the side rocker arm assembly, and the torsion bar. When the wheel bounces, the side rocker arm assembly swings around the torsion bar axis, causing the torsion bar to produce torsional elastic deformation, thereby ensuring the elastic connection between the wheel and the pre-frame. Compared with traditional suspension, this layout reduces the space occupation of the motor vehicle cargo compartment, reduces the unsprung mass, achieves a balance between lightweight and strength, and is suitable for the production of low-floor vehicles.

[0016] 2. The vehicle height and suspension stiffness are adjustable. By adjusting the side adjustment rod, the distance from the side rocker arm to the left and right lower arm or the left and right shock absorber cylinder can be changed, and the preload height of the wheel can be changed respectively to adjust the vehicle height. The suspension stiffness can be adjusted by adjusting the diameter of the torsion bar and the axial stiffness of the side rocker arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the assembly structure of the present invention; Figure 2 A schematic diagram of the structure of an embodiment of the present invention; Figure 3 It is a schematic diagram of the assembly of the middle adjustment rod in the present invention. DETAILED DESCRIPTION

[0018] like Figures 1 to 3 As shown, a transverse torsion bar spring for a motor vehicle suspension comprises a transversely extending torsion bar 1, wherein the middle position of the torsion bar 1 is circumferentially fixedly connected to an intermediate rocker arm assembly, and both ends of the torsion bar 1 are circumferentially fixedly connected to side rocker arm assemblies, forming an E-shaped transverse torsion bar spring for axially positioning the torsion bar 1; The intermediate rocker arm assembly includes an intermediate rocker arm 2 and an intermediate adjustment rod 4. One end of the intermediate rocker arm 2 is circumferentially fixedly connected to the middle of the torsion bar 1, and the other end is fixedly connected to the upper end of the intermediate adjustment rod 4. The lower end of the intermediate adjustment rod 4 extends into a longitudinal strip hole 5 opened on the frame crossbeam or the subframe crossbeam, and a limiting device is used to prevent the intermediate adjustment rod 4 from exiting the strip hole 5. The side rocker arm assembly includes a side rocker arm 7 and a side adjusting rod 8. One end of the left and right rocker arms 7 are circumferentially fixed to the two ends of the torsion bar 1, and the other ends of the left and right rocker arms 7 are movably connected to the upper ends of the left and right adjusting rods 8 through ball joints, and the lower ends of the left and right adjusting rods 8 are fixedly connected to the left and right lower swing arms or the left and right shock absorber cylinders.

[0019] In this embodiment, the torsion bar 1 is composed of a left torsion bar 12 and a right torsion bar 13, both ends of the left and right torsion bars are provided with external splines, one end of the intermediate rocker arm 2 is fixedly provided with a transversely extending internal spline sleeve 10, and a partition wall 14 is provided in the internal spline sleeve 10, and the partition wall 14 divides the internal spline sleeve 10 into two, forming two internal spline blind holes open to the lateral ends, and one end of the side rocker arm 7 is fixedly provided with a transversely extending internal spline blind hole tube 11; one end of the left torsion bar 12 is fixed with the internal spline blind hole tube 11; The key sleeve 10 is meshed with the other end thereof and meshed with the inner spline blind hole tube 11 of the left rocker arm 7. One end of the left torsion bar 12 abuts against the partition wall 14 and the other end abuts against the bottom of the inner spline blind hole tube 11 to axially position the left torsion bar 12. One end of the right torsion bar 13 is meshed with the inner spline sleeve 10 and the other end is meshed with the inner spline blind hole tube 11 of the right rocker arm 7. One end of the right torsion bar 13 abuts against the partition wall 14 and the other end abuts against the bottom of the inner spline blind hole tube 11 to axially position the right torsion bar 13. In another embodiment, the torsion bar 1 is a whole torsion bar 1, and external splines are provided at the middle position and both ends of the torsion bar 1. One end of the intermediate rocker arm 2 is fixedly provided with a transversely extending internal spline sleeve 10, and the internal spline sleeve 10 is meshed with the external splines in the middle of the torsion bar 1. One end of the side rocker arm 7 is fixedly provided with a transversely extending internal spline blind hole tube 11, and the internal spline blind hole tube 11 is meshed with the external splines at both ends of the torsion bar 1. The two ends of the torsion bar 1 abut against the bottom of the hole of the internal spline blind hole tube 11 to achieve axial positioning of the torsion bar 1. It is best not for the torsion bar 1 to be a whole spline bar, because the spline bar is easily damaged when twisted.

[0020] In this embodiment, the intermediate adjustment rod 4 is an externally threaded rod, and a through hole is provided at one end of the intermediate rocker arm 2. The axial direction of the through hole forms an angle of 90 degrees with the axial direction of the intermediate rocker arm 2. The intermediate adjustment rod 4 passes through the through hole of the intermediate rocker arm 2, and the intermediate rocker arm 2 is fixedly connected to the upper end of the intermediate adjustment rod 4 by two bolts arranged on the upper and lower sides of the intermediate rocker arm 2. In another embodiment, the intermediate adjusting rod 4 is an externally threaded rod, and an internally threaded hole is opened at one end of the intermediate rocker arm 2. The axial direction of the internally threaded hole and the axial direction of the intermediate rocker arm 2 form an angle of 90 degrees. The upper end of the intermediate adjusting rod 4 is threadedly engaged in the internally threaded hole of the intermediate rocker arm 2, and the intermediate rocker arm 2 is fixedly connected to the upper end of the intermediate adjusting rod 4.

[0021] The intermediate adjustment rod 4 is an externally threaded rod, and the limiting device is a limiting nut 6. The lower end of the intermediate adjustment rod 4 extends into a longitudinal strip hole 5 opened on the frame crossbeam or the sub-frame crossbeam, and is threadedly matched with a limiting nut 6. The outer diameter of the limiting nut 6 should be larger than the width of the strip hole 5, so as to prevent the intermediate adjustment rod 4 from exiting the strip hole 5.

[0022] The ball joint comprises a ball pin 15 and a ball seat 16. The transversely extending ball pin 15 is fixedly arranged at one end of the side rocker arm 7, and the ball seat 16 is fixedly connected to the upper end of the side adjustment rod 8. In this embodiment, the side adjustment rod 8 is an externally threaded rod, and the radially extending portion of the ball seat 16 is provided with an internally threaded hole. The upper end of the side adjustment rod 8 is threadedly engaged in the internally threaded hole of the ball seat 16 to form a fixed connection. The side adjustment rod 8 is also threadedly engaged with a nut, and the nut abuts against the upper end of the radially extending portion of the ball seat 16 to assist in fixing the ball seat 16 to the upper end of the side adjustment rod 8. In another embodiment, the side adjustment rod 8 is an externally threaded rod, a through hole is provided in the radial extension portion of the ball seat 16, the side adjustment rod 8 passes through the through hole of the ball seat 16, and the ball seat 16 is fixedly connected to the upper end of the side adjustment rod 8 by two bolts.

[0023] The middle adjusting rod 4 is provided with a slider 17, the upper end surface of the slider 17 is a circular arc sliding surface, and the lower end surface is in contact with the limit device. The frame crossbeam or the sub-frame crossbeam is provided with an arc cover plate 18 that cooperates with the circular arc sliding surface, and the arc cover plate 18 is provided with a strip hole 5 to facilitate the longitudinal swing of the middle adjusting rod 4.

[0024] Working principle: When the wheels on both sides are subjected to vertical load and bounce, the side rocker arm assembly swings around the torsion bar axis, causing the torsion bar to produce torsional elastic deformation, thereby ensuring the elastic connection between the wheel pre-frame.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A transverse torsion bar spring for a motor vehicle suspension, characterized in that: It comprises a transversely extending torsion bar (1), wherein the middle position of the torsion bar (1) is circumferentially fixedly connected to an intermediate rocker arm assembly, and both ends of the torsion bar (1) are respectively circumferentially fixedly connected to side rocker arm assemblies, forming an E-shaped transverse torsion bar spring for axially positioning the torsion bar (1); The intermediate rocker arm assembly comprises an intermediate rocker arm (2) and an intermediate adjustment rod (4); one end of the intermediate rocker arm (2) is circumferentially fixedly connected to the middle of the torsion bar (1), and the other end is fixedly connected to the upper end of the intermediate adjustment rod (4); the lower end of the intermediate adjustment rod (4) extends into a longitudinal strip hole (5) provided on a frame crossbeam or a subframe crossbeam, and a limiting device is used to prevent the intermediate adjustment rod (4) from exiting the strip hole (5); The side rocker arm assembly comprises a side rocker arm (7) and a side adjustment rod (8); one end of the left and right rocker arms (7) are respectively circumferentially fixed to the two ends of the torsion bar (1); the other ends of the left and right rocker arms (7) are respectively movably connected to the upper ends of the left and right adjustment rods (8) through ball joints; and the lower ends of the left and right adjustment rods (8) are respectively fixedly connected to the left and right lower swing arms or the left and right shock absorber cylinders.

2. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The torsion bar (1) is composed of a left torsion bar (12) and a right torsion bar (13), both ends of the left and right torsion bars are provided with external splines, one end of the intermediate rocker arm (2) is provided with an internal spline sleeve (10), a partition wall (14) is provided inside the internal spline sleeve (10), and one end of the side rocker arm (7) is provided with an internal spline blind hole tube (11), and the two ends of the left and right torsion bars are respectively meshed with the internal spline sleeve (10) and the internal spline blind hole tube (11), and abut against the bottom of the hole and the partition wall (14) of the internal spline blind hole tube (11), so as to achieve axial positioning of the torsion bar (1).

3. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The torsion bar (1) is provided with external splines at the middle position and both ends; one end of the intermediate rocker arm (2) is provided with an internal spline sleeve (10), the internal spline sleeve (10) meshes with the external splines at the middle portion of the torsion bar (1); one end of the side rocker arm (7) is provided with an internal spline blind hole tube (11), the internal spline blind hole tube (11) meshes with the external splines at both ends of the torsion bar (1); the two ends of the torsion bar (1) abut against the bottom of the hole of the internal spline blind hole tube (11), so as to achieve axial positioning of the torsion bar (1).

4. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The intermediate adjustment rod (4) is an externally threaded rod, one end of the intermediate rocker arm (2) is provided with an internally threaded hole, and the upper end of the intermediate adjustment rod (4) is threadedly engaged in the internally threaded hole of the intermediate rocker arm (2); Alternatively, the intermediate adjustment rod (4) is an externally threaded rod, a through hole is provided at one end of the intermediate rocker arm (2), the intermediate adjustment rod (4) passes through the through hole of the intermediate rocker arm (2), and the intermediate rocker arm (2) is fixedly connected to the upper end of the intermediate adjustment rod (4) by means of bolts.

5. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The intermediate adjustment rod (4) is an externally threaded rod, the limiting device is a limiting nut (6), the lower end of the intermediate adjustment rod (4) extends into a longitudinal strip hole (5) provided on a frame crossbeam or a sub-frame crossbeam, and is threadedly engaged with a limiting nut (6) to prevent the intermediate adjustment rod (4) from exiting the strip hole (5).

6. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The ball joint comprises a ball pin (15) and a ball seat (16); the transversely extending ball pin (15) is fixedly arranged at one end of the side rocker arm (7); and the ball seat (16) is fixedly connected to the upper end of the side adjustment rod (8).

7. The transverse torsion bar spring for a motor vehicle suspension according to claim 6, characterized in that: The side adjustment rod (8) is an externally threaded rod, the radially extending portion of the ball seat (16) is provided with an internally threaded hole, and the upper end of the side adjustment rod (8) is threadedly engaged in the internally threaded hole of the ball seat (16); Alternatively, the side adjustment rod (8) is an externally threaded rod, a through hole is provided on a radially extending portion of the ball seat (16), the side adjustment rod (8) passes through the through hole of the ball seat (16), and the ball seat (16) is fixedly connected to the upper end of the side adjustment rod (8) by means of bolts.

8. The transverse torsion bar spring for a motor vehicle suspension according to claim 1, characterized in that: The middle adjustment rod (4) is provided with a slider (17), the upper end surface of the slider (17) is a circular arc sliding surface, and the lower end surface is in contact with the limit device, the frame cross beam or the sub-frame cross beam is provided with an arc cover plate (18) that cooperates with the circular arc sliding surface, and the arc cover plate (18) is provided with a strip hole (5) to facilitate the longitudinal swing of the middle adjustment rod (4).

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