A device and method for detecting the influence of longitudinal torsion on vehicle braking deviation

Abstract

The present invention relates to the field of vehicle technology, and discloses a device and method for detecting the effect of longitudinal torsion on vehicle braking deviation. The detection device comprises: a test bench for mounting both ends of a leaf spring assembly; a limit bracket detachably connected between the middle of the leaf spring assembly and the vehicle frame or the test bench, wherein the limit bracket is respectively mounted with a first strain gauge and a second strain gauge on both sides along the length direction of the leaf spring assembly; a connecting support fixed to the bottom of the leaf spring assembly; a torque device for applying torque to the connecting support; and a pressure device for applying pressure to the connecting support. The present invention can measure the relationship between braking deceleration and longitudinal torque angle. By measuring the amount of braking deviation under braking deceleration, the effect of the longitudinal torque angle on the amount of braking deviation can be determined, thereby facilitating the formulation of anti-longitudinal torque measures to reduce deviation, ensure straight-line vehicle travel, and ensure driving safety.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a device and method for detecting the influence of longitudinal torsion on vehicle braking deviation. Background Art

[0002] During vehicle braking, deceleration occurs, which causes longitudinal torsion in the front leaf spring assembly. This longitudinal torsion causes wheel deflection, impacting the wheel ball pin angle and altering the trajectory of the steering tie rod terminal, leading to brake yaw. Severe brake yaw can cause the rear axle to skid, resulting in violent vehicle rotation and partial or complete loss of control, potentially leading to a traffic accident. Therefore, to minimize brake yaw, the degree of longitudinal torsion in the front leaf spring assembly needs to be reduced. However, there is currently no effective method to measure the effect of longitudinal torsion on brake yaw. Summary of the Invention

[0003] The purpose of the present invention is to provide a device and method for detecting the influence of longitudinal torsion on vehicle braking deviation, so as to measure the influence of the longitudinal torsion angle on the braking deviation amount.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] One aspect of the present invention is to provide a device for detecting the effect of longitudinal torsion on vehicle braking deviation, comprising:

[0006] Test bench for mounting both ends of the leaf spring assembly;

[0007] A limit bracket, the limit bracket being detachably connected between the middle portion of the leaf spring assembly and the vehicle frame or the test bench, and the limit bracket being respectively provided with a first strain gauge and a second strain gauge on both sides along the length direction of the leaf spring assembly;

[0008] A connecting support, the connecting support being fixed to the bottom of the leaf spring assembly;

[0009] a torque device for applying torque to the connecting support;

[0010] A pressure device is used to apply pressure to the connecting support.

[0011] Preferably, the limiting bracket includes a base plate, a support column, and a top frame. The base plate is detachably connected to the leaf spring assembly, the support column is fixed to the base plate, the top frame is fixed to the top of the support column, the top frame is detachably connected to the vehicle frame or the test bench, and the first strain gauge and the second strain gauge are fixed to the side walls of the support column.

[0012] Preferably, the first strain gauge and the second strain gauge are arranged in parallel and perpendicular to the length direction of the leaf spring assembly.

[0013] Preferably, the first strain gauge and the second strain gauge are located at the same height.

[0014] Preferably, a pad is fixed to the bottom of the leaf spring, and the pad is fixed to the axle I-beam or the connecting support.

[0015] Preferably, the torque device is arranged on a side of the connecting support, and the pressure device is arranged below the connecting support.

[0016] Another aspect of the present invention is to provide a detection method of the detection device for detecting the effect of longitudinal torsion on vehicle braking deviation as described above, comprising:

[0017] Measure the brake deviation under multiple braking decelerations and obtain the relationship between the braking deceleration and the brake deviation;

[0018] Fix the limit bracket between the leaf spring assembly and the vehicle frame, and measure the test values ​​of the first strain gauge and the second strain gauge under multiple braking decelerations;

[0019] Install the leaf spring assembly on the test bench, calibrate the leaf spring assembly, and measure the longitudinal torque angle under braking deceleration;

[0020] The steps of calibrating the leaf spring assembly are repeated to measure the longitudinal button angle under various braking decelerations, and the relationship between the braking deceleration and the longitudinal button angle is obtained;

[0021] According to the relationship between braking deceleration and braking deviation, and the relationship between braking deceleration and longitudinal knob angle, the relationship between longitudinal knob angle and braking deviation is obtained.

[0022] Preferably, the step of calibrating the leaf spring assembly includes:

[0023] Fix the limit bracket between the leaf spring assembly and the test bench;

[0024] Apply torque and pressure to the connecting support so that the values ​​of the first strain gauge and the second strain gauge are consistent with the corresponding test values;

[0025] Keep the torque and pressure unchanged and remove the lower limit bracket;

[0026] Measure the rotation angle of the leaf spring mounting surface and record it as the longitudinal button angle.

[0027] Preferably, the braking deceleration is in the range of 0 to 5.4 m / s.

[0028] Compared with the prior art, the device and method for detecting the effect of longitudinal torsion on vehicle braking deviation in the embodiment of the present invention have the following beneficial effects:

[0029] In an embodiment of the present invention, a device for detecting the effect of longitudinal torsion on vehicle braking deviation is provided. A limit bracket is used to form a rigid connection between the vehicle frame and the leaf spring assembly, preventing the leaf spring from generating longitudinal buckling. Strain gauges are installed on both sides of the limit bracket to measure the strain at the positions on both sides of the limit bracket under braking deceleration, which is used as the actual vehicle test value. The leaf spring assembly is mounted on a test bench, allowing for offline calibration of the leaf spring assembly. Torque and pressure are applied to the leaf spring assembly. When the strain gauge values ​​of the limit bracket match those of the actual vehicle test, torque and pressure values ​​corresponding to the braking deceleration of the test are obtained. At this point, the torque and pressure values ​​are maintained constant, and the limit bracket is removed. The leaf spring assembly loses its rigid connection with the limit bracket and deforms longitudinally. Measuring the angle of this longitudinal buckle yields the longitudinal buckle angle at the same braking deceleration as in the actual vehicle test. By measuring the amount of braking deviation under braking deceleration, the relationship between the longitudinal buckle angle and the deviation amount can be determined, thereby determining the effect of the longitudinal buckle angle on the braking deviation amount. This facilitates the formulation of anti-longitudinal buckle measures to reduce deviation, ensure straight travel, and ensure driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic diagram of the connection between the limiting bracket and the vehicle frame in an embodiment of the present invention;

[0031] Figure 2 Schematic diagram of the connection between the limit bracket and the test bench in an embodiment of the present invention;

[0032] Figure 3 yes Figure 2 A magnified view of part A;

[0033] Figure 4 is a schematic front view of a position limiting bracket according to an embodiment of the present invention;

[0034] Figure 5 is a schematic top view of a position limiting bracket according to an embodiment of the present invention;

[0035] Figure 6 is a side view schematic diagram of a position limiting bracket in an embodiment of the present invention;

[0036] In the figure, 1, test bench; 2, limit bracket; 21, bottom plate; 211, locking bolt; 22, support column; 23, top frame; 3, first strain gauge; 4, second strain gauge; 5, connecting support; 6, torque device; 7, pressure device; 8, pad;

[0037] 10. Leaf spring assembly; 20. Vehicle frame; 30. Axle I-beam. DETAILED DESCRIPTION

[0038] In the description of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0040] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0041] like Figure 1 - Figure 6 As shown, a detection device for the influence of longitudinal torsion on vehicle braking deviation according to an embodiment of the present invention includes a test bench 1, a limit bracket 2, a connecting support 5, a torque device 6 and a pressure device 7, wherein the test bench 1 is used to install both ends of the leaf spring assembly 10, serves as a support frame when calibrating the leaf spring assembly 10, and acts as a frame 20 during offline calibration; the limit bracket 2 is detachably connected between the middle part of the leaf spring assembly 10 and the frame 20 or the test bench 1, so that a rigid connection is formed between the leaf spring assembly 10 and the frame 20 or the test bench 1, thereby avoiding the leaf spring A longitudinal buckle occurs; the limiting bracket 2 is respectively installed with a first strain gauge 3 and a second strain gauge 4 on both sides of the leaf spring assembly 10 in the length direction. The strain values ​​on both sides of the limiting bracket 2 are measured by the first strain gauge 3 and the second strain gauge 4. The measured strain is used as a bridge between the actual vehicle test and the offline calibration, so that the braking deceleration of the offline calibration is consistent with the braking deceleration of the actual vehicle test; the connecting support 5 is fixed to the bottom of the leaf spring assembly 10; the torque device 6 is used to apply torque to the connecting support 5; the pressure device 7 is used to apply pressure to the connecting support 5. The torque device 6 is arranged on the side of the connecting support 5, and the pressure device 7 is arranged below the connecting support 5. The structures of the torque device 6 and the pressure device 7 are both existing technologies and will not be described in detail in the present invention.

[0042] The present invention forms a rigid connection between the vehicle frame 20 and the leaf spring assembly 10 through the limit bracket 2, so that the leaf spring does not produce longitudinal knots. By installing strain gauges on both sides of the limit bracket 2, the position strain of the limit bracket 2 on both sides under braking deceleration is measured as the actual vehicle test value; by installing the leaf spring assembly 10 on the test bench 1, the leaf spring assembly 10 can be calibrated offline, and torque and pressure are applied to the leaf spring assembly 10. When the strain gauge value of the limit bracket 2 is consistent with the strain gauge value during the actual vehicle test, the braking value consistent with the test is obtained. The torque and pressure values ​​corresponding to the deceleration; at this time, keep the torque and pressure values ​​unchanged, then remove the limit bracket 2, the leaf spring assembly 10 loses the rigid connection of the limit bracket 2 and the longitudinal buckle deformation occurs, and the longitudinal buckle angle is measured to obtain the longitudinal buckle angle under the same braking deceleration as that in the actual vehicle test; by measuring the braking deviation under braking deceleration, the relationship between the longitudinal buckle angle and the deviation amount can be obtained, and the influence of the longitudinal buckle angle on the braking deviation amount can be obtained, so as to facilitate the formulation of anti-longitudinal buckle measures to reduce the deviation amount, ensure the vehicle to travel in a straight line, and ensure driving safety.

[0043] like Figure 4 - Figure 6 As shown, the limiting bracket 2 includes a base plate 21, a support column 22, and a top frame 23. The base plate 21 is detachably connected to the leaf spring assembly 10, the support column 22 is fixed to the base plate 21, and the top frame 23 is fixed to the top of the support column 22. The top frame 23 is detachably connected to the vehicle frame 20 or the test bench 1, and the first strain gauge 3 and the second strain gauge 4 are fixed to the side walls of the support column 22. The base plate 21 and the leaf spring can be locked and fixed by locking bolts 211, making them easy to disassemble; the top frame 23 is fixed to the vehicle frame 20 or the test bench 1 by bolts. There can be multiple support columns 22, and the multiple support columns 22 are arranged at intervals along the length direction of the base plate 21. The first strain gauge 3 is arranged on the front side of the support column 22 at the front end, and the second strain gauge 4 is arranged on the rear side of the support column 22 at the rear end. Among them, the side facing the front of the vehicle when the leaf spring assembly 10 is installed on the frame 20 is the front side, and the side facing the rear of the vehicle when the leaf spring assembly 10 is installed on the frame 20 is the rear side.

[0044] In this embodiment, the first strain gauge 3 and the second strain gauge 4 are arranged in parallel and perpendicular to the length direction of the leaf spring assembly 10. Furthermore, the first strain gauge 3 and the second strain gauge 4 are located at the same height.

[0045] In this embodiment, a pad 8 is fixed to the bottom of the leaf spring, and the pad 8 is fixed to the axle I-beam 30 or the connecting support 5. The pad 8 is fixed to the axle I-beam 30, and the leaf spring assembly 10 can be fixed to the axle I-beam 30. The pad 8 is fixed to the connecting support 5, and the leaf spring assembly 10 can be fixed to the connecting support 5.

[0046] In this embodiment, the test bench 1 acts as the vehicle frame 20 during offline calibration. The test bench 1 is in the shape of a gate, including two columns and a crossbeam. Both ends of the leaf spring assembly 10 and the limit bracket 2 are installed on the crossbeam.

[0047] The detection method of the detection device for detecting the influence of longitudinal torsion on vehicle braking deviation of the present invention comprises the following steps:

[0048] Step S1, measuring the braking deviation under multiple braking decelerations to obtain a relationship between the braking deceleration and the braking deviation; wherein the braking deceleration is within a range of 0 to 5.4 m / s, for example, the braking deceleration may be 1 m / s, 2 m / s, 3 m / s, 3.5 m / s, 4 m / s, 5 m / s, 5.4 m / s, etc.;

[0049] Step S2, fixing the limiting bracket 2 between the leaf spring assembly 10 and the vehicle frame 20, performing a real vehicle test, and measuring the test values ​​of the first strain gauge 3 and the second strain gauge 4 under multiple braking decelerations;

[0050] Step S3, installing the leaf spring assembly 10 on the test bench 1, calibrating the leaf spring assembly 10, and measuring the longitudinal angle under braking deceleration;

[0051] Step S4, looping through the steps of calibrating the leaf spring assembly 10, measuring the longitudinal angle of the spring under various braking decelerations, and obtaining the relationship between the braking deceleration and the longitudinal angle of the spring;

[0052] Step S5, obtaining the relationship between the longitudinal knob angle and the braking deviation amount according to the relationship between the braking deceleration and the braking deviation amount and the relationship between the braking deceleration and the longitudinal knob angle.

[0053] The present invention obtains the test values ​​of the strain gauge under various braking decelerations by conducting actual vehicle tests on the leaf spring assembly 10; when the leaf spring assembly 10 is calibrated offline, the same braking deceleration conditions as those in the actual vehicle test can be obtained through the measured values ​​of the strain gauge, thereby measuring the longitudinal knob angle under braking deceleration, obtaining the relationship between the longitudinal knob angle and the braking deviation amount, and obtaining the influence of the longitudinal knob angle on the braking deviation amount.

[0054] In step S1, the braking deviation is determined by measuring the distance the vehicle deviates from the original straight track per unit linear distance after stopping under braking deceleration. Multiple braking deceleration values ​​are selected within the range of 0 to 5.4 m / s, and the braking deviation is determined at each braking deceleration.

[0055] In step S2, at each braking deceleration, a test value of the first strain gauge 3 and a test value of the second strain gauge 4 are obtained. The two test values ​​constitute a value pair, which is a one-to-one correspondence. This makes it convenient to obtain the braking deceleration under the same conditions as the actual vehicle test according to the strain gauge values ​​in the offline calibration step.

[0056] In step S3 , the leaf spring assembly 10 is mounted on the test bench 1 , and the test bench 1 serves as the vehicle frame 20 to fix the leaf spring assembly 10 .

[0057] The steps for calibrating the leaf spring assembly 10 include: fixing the limit bracket 2 between the leaf spring assembly 10 and the test bench 1 to form a rigid connection between the leaf spring assembly 10 and the test bench 1 to prevent the leaf spring assembly 10 from having a longitudinal buckle; applying torque and pressure to the connecting support 5, and continuously adjusting the torque and pressure so that the values ​​of the first strain gauge 3 and the second strain gauge 4 are consistent with the corresponding test values, thereby obtaining the same braking deceleration conditions as the actual vehicle test; keeping the torque and pressure unchanged, removing the limit bracket 2. At this time, the leaf spring without the fixing effect of the limit bracket 2 will produce a longitudinal torsional deformation under the action of torque and pressure; measuring the rotation angle of the leaf spring mounting surface, recorded as the longitudinal buckle angle, and obtaining the longitudinal buckle angle under a single braking deceleration.

[0058] In step S5, the larger the longitudinal knob angle is, the larger the braking deviation is. Therefore, by reducing the longitudinal knob, the braking deviation can be reduced.

[0059] It should be noted that other specific embodiments of the method for detecting the influence of longitudinal torsion on vehicle braking deviation of the present invention are roughly the same as the specific embodiments of the device for detecting the influence of longitudinal torsion on vehicle braking deviation mentioned above, and will not be repeated here.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A device for detecting the effect of longitudinal torsion on vehicle braking deviation, characterized in that: include: Test bench for mounting both ends of the leaf spring assembly; A limit bracket, the limit bracket being detachably connected between the middle portion of the leaf spring assembly and the vehicle frame or the test bench, and the limit bracket being respectively provided with a first strain gauge and a second strain gauge on both sides along the length direction of the leaf spring assembly; A connecting support, the connecting support being fixed to the bottom of the leaf spring assembly; a torque device for applying torque to the connecting support; a pressure device for applying pressure to the connection support; Apply torque and pressure to the leaf spring assembly so that the values ​​of the first strain gauge and the second strain gauge are consistent with the corresponding test values, respectively, to obtain torque and pressure values ​​corresponding to the tested braking deceleration; keep the torque and pressure values ​​unchanged, remove the lower limit bracket, and measure the rotation angle of the leaf spring mounting surface to obtain the longitudinal button angle at the same braking deceleration as in the actual vehicle test.

2. The device for detecting the influence of longitudinal torsion on vehicle braking deviation according to claim 1, characterized in that: The limiting bracket includes a base plate, a support column, and a top frame. The base plate is detachably connected to the leaf spring assembly, the support column is fixed to the base plate, the top frame is fixed to the top of the support column, and the top frame is detachably connected to the vehicle frame or the test bench. The first strain gauge and the second strain gauge are fixed to the side walls of the support column.

3. The device for detecting the influence of longitudinal torsion on vehicle braking deviation according to claim 1 or 2, characterized in that: The first strain gauge and the second strain gauge are arranged in parallel and perpendicular to the length direction of the leaf spring assembly.

4. The device for detecting the influence of longitudinal torsion on vehicle braking deviation according to claim 3, characterized in that: The first strain gauge and the second strain gauge are located at the same height.

5. The device for detecting the influence of longitudinal torsion on vehicle braking deviation according to claim 1, characterized in that: A pad is fixed to the bottom of the leaf spring, and the pad is fixed to the axle I-beam or the connecting support.

6. The device for detecting the influence of longitudinal torsion on vehicle braking deviation according to claim 1, characterized in that: The torque device is arranged on the side of the connecting support, and the pressure device is arranged below the connecting support.

7. A detection method for the detection device of the effect of longitudinal torsion on vehicle braking deviation according to any one of claims 1 to 6, characterized in that: include: Measure the brake deviation under multiple braking decelerations and obtain the relationship between the braking deceleration and the brake deviation; Fix the limit bracket between the leaf spring assembly and the vehicle frame, and measure the test values ​​of the first strain gauge and the second strain gauge under multiple braking decelerations; Install the leaf spring assembly on the test bench, calibrate the leaf spring assembly, and measure the longitudinal torque angle under braking deceleration; The steps of calibrating the leaf spring assembly are repeated to measure the longitudinal button angle under various braking decelerations, and the relationship between the braking deceleration and the longitudinal button angle is obtained; According to the relationship between braking deceleration and braking deviation, and the relationship between braking deceleration and longitudinal knob angle, the relationship between longitudinal knob angle and braking deviation is obtained; The steps for calibrating a leaf spring assembly include: Fix the limit bracket between the leaf spring assembly and the test bench; Apply torque and pressure to the connecting support so that the values ​​of the first strain gauge and the second strain gauge are consistent with the corresponding test values; Keep the torque and pressure unchanged and remove the lower limit bracket; Measure the rotation angle of the leaf spring mounting surface and record it as the longitudinal button angle.

8. The detection method according to claim 7, characterized in that The braking deceleration is within the range of 0~5.4m / s.

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