Steering column performance test bench and test method thereof

Abstract

The invention discloses a steering column performance test bench and a test method thereof, and relates to the technical field of steering column performance test. The steering column performance test bench comprises a detection bench, a servo motor and a driving assembly, and is used for driving the upper surface of the detection bench to rotate. A first hydraulic rod is hinged to the mounting frame, a same connecting plate is hinged to the other end of the first hydraulic rod and the lower position of the outward side of the mounting frame, two clamping pieces are arranged on the upper side and the lower side of the outer side of the connecting plate, and the upper clamping piece and the lower clamping piece on the same side are used in cooperation and used for clamping a steering column; and the moving assembly is used for driving the mounting frame, the first hydraulic rod above the mounting frame, the clamping piece and the steering column to do horizontal reciprocating motion. According to the invention, multiple performance tests can be carried out on the same steering column in sequence, the automation degree is high, the overall test time is shortened, and the test efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of steering column performance testing, and specifically to a steering column performance testing test bench and its testing method. Background Art

[0002] The steering column is an important part of the vehicle steering system and is a component connecting the steering wheel and the steering mechanism. It mainly consists of parts such as the steering shaft, the steering column sleeve, and the universal joint, and plays roles such as transmitting the steering torque, supporting the steering wheel, and absorbing energy during vehicle collisions.

[0003] As the core transmission component of the vehicle steering system, the technological evolution of the steering column is closely related to the development of the automotive industry. In the early days, the mechanical steering column adopted a simple two-section sleeve and universal joint structure, which could only achieve the basic function of steering force transmission. With the popularization of electric power steering technology, integrating the motor module inside the column has become a standard configuration, with intelligent functions such as power steering and damping adjustment. In recent years, the rise of the steer-by-wire system has put forward higher requirements for the column, which need to support electronic signal transmission and redundant safety design. The future development trend focuses on lightweight, high compatibility, and extreme environment adaptability.

[0004] The performance testing of the steering column is the core link to ensure the safety and reliability of the vehicle steering system. Its necessity stems from multiple requirements for driving safety, regulatory compliance, and technological iteration: it is necessary to verify its anti-torsion stiffness, fatigue life, and collision energy absorption ability under complex road conditions, and at the same time, to cope with the challenges brought by new technologies such as steer-by-wire.

[0005] Currently, the main testing items for the performance testing of the steering column are as follows: Durability testing, using an electric vibration table and a multi-axis linkage system to simulate road vibration and cyclic loads, and conducting hundreds of thousands of fatigue tests to evaluate failure modes such as thread wear and connection loosening.

[0006] Corrosion and environmental resistance testing, through a salt spray test chamber, a temperature control box, and an ultraviolet aging box, to evaluate the material corrosion, coating peeling, and functional stability of the steering column in environments such as the ocean, extreme temperature, and sunlight.

[0007] Connection reliability testing, using an axial tensile testing machine to verify the tensile strength of the spline / bolt, and checking the tightening torque with a torque wrench to ensure the connection firmness between the steering column and the steering wheel and the steering gear, and prevent loosening or breakage caused by vibration or impact.

[0008] Noise and vibration testing, with the help of an acoustic analyzer and a laser vibrometer, to detect the noise spectrum and surface vibration during the steering operation, locate the noise sources such as bearing wear and spline clearance, and optimize the NVH performance.

[0009] Currently, various tests are carried out on the steering column by multiple different test institutions. During the test process, it is necessary to manually transfer the steering column from one test institution to the next, with a low degree of automation. In addition, the existing test system cannot obtain the comprehensive performance of the steering column. Therefore, a performance test bench for the steering column and its test method are proposed to solve the above problems. Summary of the Invention

[0010] According to the above deficiencies in the prior art, the present invention provides a performance test bench and test method for a steering column, which can sequentially perform multiple performance tests on the same steering column, with a high degree of automation, shorten the overall test time, and improve the test efficiency.

[0011] To achieve the above objectives, the present invention provides a performance test bench for a steering column, including a detection table, which is a rotatable support frame with a circular upper surface; a servo motor, which is installed on the outer bottom surface of the inner side of the detection table by screws; a driving component, which is located in the middle of the detection table and is connected to the servo motor, and is used to drive the upper surface of the detection table to rotate; a mounting frame, which is symmetrically arranged above the detection table, and a first hydraulic rod is hinged on the mounting frame. The other end of the first hydraulic rod and the lower position on the outer side of the mounting frame are hinged to the same connecting plate. Two clamping members are arranged up and down on the outer side of the connecting plate. The upper and lower two clamping members on the same side are used in cooperation to clamp the steering column; a moving component, which is located on the upper surface of the detection table and is arranged at the bottom of the mounting frame, and is used to drive the mounting frame, the first hydraulic rod, the clamping members and the steering column above it to perform horizontal reciprocating movement; along the circumferential direction of the detection table, a durability test bench for the steering column, a noise and vibration test device, an environmental resistance test device and a corrosion test device are sequentially placed.

[0012] Further, the detection table includes a table top, a rotating column and a base, which are arranged from top to bottom in sequence. The lower end of the rotating column is rotatably connected to the base, and the servo motor is installed on the base; the mounting frame includes a cross plate and a frame body part, and the frame body part is installed on the upper end of the cross plate by screws, and the cross plate is installed on the moving component.

[0013] Further, the driving component includes a first gear and a toothed ring meshed with it. The first gear is installed on the output end of the servo motor, and the toothed ring is sleeved outside the rotating column and is fixedly connected to the rotating column.

[0014] Further, the moving component includes two linear motors, which are installed between the table top and the cross plate and can drive the cross plate and the structures on it to perform horizontal reciprocating movement.

[0015] Further, the driving component includes a rotating mechanism and a vertical moving mechanism. The rotating mechanism is connected to the servo motor, the vertical moving mechanism is connected to the rotating mechanism, the vertical moving mechanism is arranged on one side of the moving component and is clamped and connected thereto. The vertical moving mechanism enables the moving component to operate by rotating the required angle through the rotating mechanism and the servo motor, so that the mounting frame and the structures thereon move horizontally in a reciprocating manner; the rotating mechanism includes two meshing fifth gears, and first transmission members are respectively installed on the two fifth gears. One fifth gear is installed at the output end of the servo motor, the first transmission member on this fifth gear is installed at its upper end, and two coaxially arranged fourth gears are installed at the lower end of this first transmission member. The two fourth gears are rotatably connected to each other and are installed on the base through a frame. The two fourth gears are irregular gears, and the sides with teeth of the two fourth gears are arranged in a staggered manner; the first transmission member on the other fifth gear is installed at its lower end, and the other end of this first transmission member is installed at the lower end of the lower fourth gear. A sixth gear is coaxially installed between this fifth gear and the first transmission member below it. The sixth gear is an irregular gear, and a seventh gear is intermittently meshed with the side away from the servo motor. A second transmission member is installed at the upper end of the seventh gear, and the other end of the second transmission member is fixedly sleeved outside the rotating column; the vertical moving mechanism includes a clamping block, a lead screw, a guide rod and a fixed frame. The clamping block is sleeved outside the lead screw and the guide rod and is threadedly connected to the lead screw. The lead screw and the guide rod are installed at the inner top of the fixed frame. The fixed frame is in an inverted L shape and is fixed on the base. Two third gears are coaxially arranged at the lower end of the lead screw; the clamping block includes a clamping part and a moving part. The clamping part is fixed on the surface of the moving part close to the rotating column and is formed by two upper and lower clamping plates, which are clamped on the moving component. The moving part is sleeved outside the lead screw and the guide rod; the upper third gear is intermittently meshed with the upper fourth gear, and the lower third gear is intermittently meshed with the lower fourth gear, which is used to drive the lead screw to rotate forward and backward, so as to realize the up and down movement of the clamping block.

[0016] Further, the moving component includes a mounting ring, a push rod, a fixing plate, a limiting rod and a mounting block. The mounting ring is sleeved outside the rotating column. The push rods are symmetrically arranged on both sides of the mounting ring, and the lower ends of the push rods are rotatably connected to the outer side surface of the mounting ring; the mounting blocks are symmetrically fixed at the bottoms of the two cross plates. The upper end of the push rod on the same side is rotatably installed at the bottom of the middle part of the mounting block on this side and penetrates through the tabletop; the fixing plates are symmetrically arranged on the tabletop and are fixed at the upper edge of the tabletop. The limiting rods are horizontally symmetrically arranged between the two fixing plates, and the pointing direction is the same as the sliding direction of the mounting block. The limiting rods penetrate through the mounting blocks at the bottoms of the two cross plates to realize the sliding guidance of the mounting blocks; one side of the mounting ring is clamped with the clamping part in the clamping block. The mounting ring drives it to move up and down through the clamping block, so that the push rods on both sides push the mounting blocks, the cross plates and pull down the mounting blocks and the cross plates, realizing the horizontal reciprocating movement of the cross plates and the structures thereon.

[0017] Further, the clamping member includes two symmetrically arranged toothed plates and two symmetrically arranged mounting plates. The mounting plates on the same side are arranged below the toothed plates. The toothed plate includes a toothing portion and a connecting portion. The connecting portion is arranged at the outer part of the bottom of the toothing portion, and the connecting portion extends into the mounting plate and is slidably connected thereto. Both the toothed plate and the mounting plate are semi-circular rings. The toothing portion of the toothed plate on one side is meshed with a second gear. The second gear is rotatably connected with a connecting block. The mounting plate below the toothed plate on this side is fixedly arranged at the inner bottom of the connecting block. A rotating block is installed at the upper end of the second gear. The rotating block is arranged above the connecting block. One end of the mounting plate on the other side is rotatably installed in the connecting block, forming a clip shape that can be opened and closed on one side with the mounting plate fixedly arranged in the connecting block. A second hydraulic rod is hingedly installed between the outer side of the rotatable mounting plate and the side wall of the connecting block. The connecting block is fixedly arranged on the connecting plate. Two elastic limit members are fixedly arranged on the connecting block for limiting the rotating block. A hemispherical groove adapted to the elastic limit member is opened at the bottom of the rotating block. Clamping blocks are linearly arranged along the semi-circumference on the inner side of the mounting plate. A sliding block is fixedly arranged on the clamping block close to one side of the mounting plate. A convex block is fixedly arranged at the part of the upper end of the sliding block away from the clamping block. An arc-shaped sliding groove adapted to the convex block is opened on the toothed plate on the same side. A semi-circular ring-shaped limit block is installed at the inner bottom of the mounting plate by screws. A plurality of grooves adapted to the sliding blocks are opened on the limit block. A stop block is arranged in the groove. The sliding block covers the outside of the corresponding stop block, and a connecting spring is fixedly arranged between the inner side wall of the end of the sliding block away from the stop block and the stop block.

[0018] The test method of the steering column performance test bench includes the following steps: obtaining the test parameter set stored in the data repository, and based on the test parameter set, obtaining the test results of each test; based on the test results of each test, obtaining the test performance qualification rate of each test; based on the test performance qualification rate of each test, obtaining the comprehensive performance of the steering column.

[0019] Further, obtaining the test performance qualification rate of each test specifically includes the following steps: The test parameter set includes noise and vibration test parameters, durability test parameters, environmental resistance test parameters, and corrosion test parameters; the noise and vibration test parameters include various part parameters, and the part parameters include noise spectrum, vibration amplitude, and vibration frequency. Based on each part parameter, the noise and vibration test values of each part are analyzed; the calculation formula of the noise and vibration test value is: ; In the formula: is the noise and vibration test value at the vibration frequency , is the actual pressure value of the noise at the vibration frequency , is the vibration amplitude at the vibration frequency , is the intensity of the noise, p is the actual pressure value of the noise, is the reference sound pressure, is the initial vibration amplitude, A is the vibration amplitude, F is the external force, k is the system stiffness, is the frequency response function, is at the vibration frequency the displacement response value, is at the vibration frequency the external force at, m is the mass of the steering concern, c is the damping coefficient, is the vibration frequency, j is the imaginary unit; Based on the noise and vibration test values of each part, determine whether there is abnormal noise in each part: Compare the noise and vibration test values of each part with the noise and vibration test thresholds of the corresponding parts in turn. If the noise and vibration test values are greater than the noise and vibration test thresholds, there is no abnormal noise; If the noise and vibration test values are not greater than the noise and vibration test thresholds, there is abnormal noise, and the position is recorded; Based on the number of abnormal noise positions, analyze and obtain the test performance qualification rate of the noise and vibration test; The durability test parameters include stress amplitude, number of cycles, material constant, material fatigue index. Based on the durability test parameters, obtain the cumulative damage value and analyze and obtain the predicted total life; The calculation formula for the predicted total life is: ; In the formula: is the predicted total life, is the remaining life, is the number of cycles that the material can withstand at , is the i-th stress amplitude, C is the material constant, cp is the material fatigue index, D is the cumulative damage value, is the material at the actual number of cycles, is the material at the acting force, is the cross-sectional area, i is the stress amplitude number, n is the total number of stress amplitudes; Compare the predicted total life with the predicted life threshold. If the predicted total life is greater than the predicted life threshold, the test performance qualification rate of the durability test is 100%; If the predicted total life is not greater than the predicted life threshold, analyze and obtain the test performance qualification rate of the durability test; The environmental resistance test parameters include temperature range value, humidity range value, material expansion coefficient, material moisture absorption rate, and analyze and obtain the comprehensive expansion value; The calculation formula for the comprehensive expansion value is: ; In the formula: is the change value of the material length under temperature change, is the thermal expansion coefficient of the material, is the initial length of the material, is the temperature change value, is the material length change value of the material under humidity change, is the hygroscopic expansion coefficient of the material, is the humidity change value, is the comprehensive expansion value; the comprehensive expansion value is successively subtracted from each reference expansion value stored in the data repository to obtain the absolute value of the expansion value difference, and the qualification rate of the test performance of the environmental resistance test corresponding to the reference expansion value corresponding to the smallest absolute value of the expansion value difference is the qualification rate of the test performance of the environmental resistance test of the comprehensive expansion value; the corrosion test parameters include corrosion duration, corrosion area, and weight loss, and the corrosion rate is analyzed; the calculation formula of the corrosion rate is: ; In the formula: R is the corrosion rate, W is the weight loss value, is the corrosion area, and t is the corrosion duration; the comprehensive expansion value is successively subtracted from each reference corrosion rate stored in the data repository to obtain the absolute value of the corrosion rate difference, and the qualification rate of the test performance of the corrosion test corresponding to the reference corrosion rate corresponding to the smallest absolute value of the corrosion rate difference is the qualification rate of the test performance of the corrosion test of the corrosion rate.

[0020] Furthermore, the qualification rates of the test performance of the noise and vibration test, the durability test, the environmental resistance test, and the corrosion test are recorded as test performance data; the test performance data is compared with the test performance reference data of each reference steering column stored in the data repository, and each parameter in the test performance data is subtracted from the corresponding reference parameter in each group of test performance reference data to obtain the absolute value of the comprehensive test performance difference, and the comprehensive performance of the steering column corresponding to the reference steering column corresponding to the test performance reference data corresponding to the smallest absolute value of the comprehensive test performance difference is the comprehensive performance of the steering column of the current test performance data.

[0021] The present invention has the following beneficial effects: (1) The steering column performance test bench, through the cooperation of the detection bench, the servo motor, the drive assembly, the mounting bracket, the connecting plate, the first hydraulic rod, the clamping member, and the moving assembly, is used to successively transport the same steering column for multiple performance tests, realizing the automatic transportation of multiple detection stations of the steering column, with high automation, shortening the overall test time, and improving the test efficiency.

[0022] (2) The steering column performance test bench, through the cooperation of the first hydraulic rod, the connecting plate, the mounting bracket, and the clamping member provided, can adjust the inclination angle of the clamped steering column according to the test requirements, which is convenient to use and has high flexibility.

[0023] (3) The steering column performance test bench, through the combined use of the set rotating block, second gear, toothed plate, mounting plate, clamping block, slider, convex block, chute, stop block and connecting spring, is used to clamp the steering column, and can clamp steering columns with different diameters, having high adaptability.

[0024] (4) The test method of the steering column performance test bench, through comprehensive performance tests, ensures the high quality of the steering column in design, manufacturing and use. Problems are discovered through tests in the design and development stage, avoiding large-scale failures in the mass production or use stage, reducing maintenance and recall costs. Durability tests and environmental resistance tests ensure the safety of the steering column in long-term use and extreme environments, reducing safety accidents caused by failures. The accumulation and analysis of test data provide data support for the design optimization of the steering column, promoting technological progress and product iteration. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of Embodiment 1 of the present invention; Figure 2 It is a schematic structural diagram of the clamping member of the present invention clamping the steering column; Figure 3 It is a schematic structural diagram of the clamping member of the present invention after opening; Figure 4 It is a schematic structural diagram of the connection between the rotating block and the elastic limiting member of the present invention; Figure 5 It is a schematic structural diagram of the clamping block of the present invention when not clamping; Figure 6 It is a schematic structural diagram of the clamping block of the present invention when clamping; Figure 7 It is a schematic structural diagram of the interior of the mounting plate of the present invention; Figure 8 It is a schematic structural diagram of Embodiment 2 of the present invention; Figure 9 It is a partial structural schematic of Embodiment 2 of the present invention Figure 1 ; Figure 10 It is a partial structural schematic of Embodiment 2 of the present invention Figure 2 ; Figure 11 It is a partial structural schematic of Embodiment 2 of the present invention Figure 3 ; Figure 12 It is a schematic overall structural layout diagram of the present invention; Figure 13 It is a schematic flow diagram of the test method of the steering column performance test bench of the present invention.

[0026] In the figure, 1 is the tabletop; 2 is the rotating column; 3 is the base; 4 is the toothed ring; 5 is the first gear; 6 is the servo motor; 7 is the linear motor; 8 is the mounting bracket; 9 is the first hydraulic rod; 10 is the connecting plate; 11 is the connecting block; 12 is the rotating block; 13 is the second gear; 14 is the toothed plate; 15 is the mounting plate; 16 is the second hydraulic rod; 17 is the clamping block; 18 is the slider; 19 is the convex block; 20 is the chute; 21 is the stop block; 22 is the connecting spring; 23 is the limit block; 24 is the mounting block; 25 is the limit rod; 26 is the fixing plate; 27 is the push rod; 28 is the mounting ring; 29 is the clamping block; 30 is the lead screw; 31 is the guide rod; 32 is the fixing frame; 33 is the third gear; 34 is the fourth gear; 35 is the first transmission member; 36 is the fifth gear; 37 is the sixth gear; 38 is the seventh gear; 39 is the second transmission member; 40 is the elastic limiting member. Detailed implementation manner

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "periphery", etc. indicating the orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0029] Next, according to Figures 1 - 12 describe the steering column performance test bench provided by the embodiments of the present invention.

[0030] Example 1, please refer to Figures 1 - 7 and Figure 12, a steering column performance test bench, including a detection bench, which is a rotatable support frame with a circular upper surface; a servo motor 6, which is installed on the outer bottom surface of the inner side of the detection bench by screws; a driving component, which is located in the middle of the detection bench and is connected to the servo motor 6 for driving the upper surface of the detection bench to rotate; a mounting frame 8, which is symmetrically arranged above the detection bench, and a first hydraulic rod 9 is hinged on the mounting frame 8. The other end of the first hydraulic rod 9 and the lower position on the outer side of the mounting frame 8 are hinged to the same connecting plate 10. Two clamping pieces are arranged up and down on the outer side of the connecting plate 10. The upper and lower two clamping pieces on the same side are used in cooperation to clamp the steering column; a moving component, which is located on the upper surface of the detection bench and is arranged at the bottom of the mounting frame 8 for driving the mounting frame 8, the first hydraulic rod 9, the clamping pieces and the steering column above it to move horizontally back and forth; a steering column durability test bench, a noise and vibration test device, an environmental resistance test device and a corrosion test device are sequentially placed in a circumferential ring along the outside of the detection bench. During the rotation of the table surface 1, the clamping pieces clamp the steering column and pass through the steering column durability test bench (for non-destructive testing), the noise and vibration test device, and the environmental resistance test device in sequence. After the above three tests, when reaching the corrosion test device, the steering column can be placed into the corrosion test device.

[0031] The steering column durability test bench mostly uses an electric vibration table and a multi-axis linkage system to collect vibration data and cyclic load spectra according to the actual road conditions and accurately simulate various complex working conditions. It can perform hundreds of thousands or even millions of fatigue tests on the steering column, so as to effectively evaluate the failure modes such as thread wear, connection looseness, and material fatigue during long-term use, and judge the fatigue life of the product.

[0032] The noise and vibration test device uses equipment such as an acoustic analyzer and a laser vibrometer. The acoustic analyzer can accurately detect the noise spectrum generated during the steering operation and obtain information such as the frequency and intensity of the noise; the laser vibrometer can non-contact measure parameters such as the vibration amplitude and vibration frequency on the surface of the steering column to locate the root causes of abnormal noises such as bearing wear and excessive spline clearance.

[0033] The environmental resistance test device uses a temperature control box to simulate extreme temperature environments (high temperature, low temperature) and an ultraviolet aging box to simulate the sunlight environment. It can accurately control environmental parameters such as temperature, humidity, and light intensity to comprehensively evaluate the material corrosion, coating peeling, performance stability, etc. of the steering column under different harsh environments.

[0034] The corrosion test device mainly uses a salt spray corrosion test to perform a corrosion test on the steering column in a specific salt spray environment. By controlling parameters such as salt spray concentration, spraying time, and test temperature, it simulates the corrosion conditions in actual use.

[0035] Specifically, the test bench includes a tabletop 1, a rotating column 2, and a base 3. The tabletop 1, the rotating column 2, and the base 3 are arranged in sequence from top to bottom. The lower end of the rotating column 2 is rotatably connected to the base 3, and a servo motor 6 is installed on the base 3; the mounting bracket 8 includes a cross plate and a frame body part. The frame body part is installed on the upper end of the cross plate by screws, and the cross plate is installed on the moving component.

[0036] The driving component includes a first gear 5 and a toothed ring 4 meshed and connected with it. The first gear 5 is installed at the output end of the servo motor 6, the toothed ring 4 is sleeved outside the rotating column 2, and is fixedly connected to the rotating column 2.

[0037] The moving component includes two linear motors 7. The linear motors 7 are installed between the tabletop 1 and the cross plate by screws, and are used to drive the cross plate and the structures thereon to perform horizontal reciprocating movement.

[0038] In this implementation, the servo motor 6 drives the first gear 5 to rotate. The first gear 5 is meshed and connected with the toothed ring 4, so that the toothed ring 4 drives the rotating column 2, the tabletop 1 installed on the rotating column 2, and each structure installed on the tabletop 1 to rotate. After each 90-degree rotation, the servo motor 6 stops operating. Subsequently, the linear motor 7 operates to drive the mounting bracket 8 and the structures installed thereon to move into the corresponding test device. After reaching the position to be tested, the linear motor 7 stops operating. There are two linear motors 7 on the tabletop 1, which can drive two sets of structures clamping the steering column to perform horizontal movement to test the two steering columns, improving the test efficiency.

[0039] Specifically, the clamping member includes two symmetrically arranged toothed plates 14 and two symmetrically arranged mounting plates 15. The mounting plates 15 on the same side are arranged below the toothed plates 14. The toothed plate 14 includes a toothed connecting portion and a connecting portion. The connecting portion is arranged at the outer part of the bottom of the toothed connecting portion, and the connecting portion extends into the mounting plate 15 and is slidably connected to it. Both the toothed plate 14 and the mounting plate 15 are semicircular rings.

[0040] The toothed connecting portion of the toothed plate 14 on one side is meshed and connected with a second gear 13. The second gear 13 is rotatably connected to a connecting block 11. The mounting plate 15 below the toothed plate 14 on this side is fixedly arranged at the inner bottom of the connecting block 11. A rotating block 12 is installed at the upper end of the second gear 13, and the rotating block 12 is arranged above the connecting block 11. One end of the mounting plate 15 on the other side is rotatably installed in the connecting block 11, forming a clip shape that can be opened and closed on one side with the mounting plate 15 fixed in the connecting block 11. A second hydraulic rod 16 is hinged and installed between the outer side of the rotatable mounting plate 15 and the side wall of the connecting block 11. The connecting block 11 is fixedly arranged on the connecting plate 10; as Figure 4As shown, a plurality of elastic limit members 40 are fixedly arranged on the connecting block 11 for limiting the rotating block 12. A hemispherical groove adapted to the elastic limit member 40 is formed at the bottom of the rotating block 12 to limit the rotating block 12 before and after rotation, so as to limit the toothed plate 14 through the second gear 13 and prevent the toothed plate 14 from reversing due to the rebounding force of the connecting spring 22. The elastic limit member 40 includes a sphere and a spring.

[0041] Clamping blocks 17 are linearly arranged along the semi - circumference on the inner side of the mounting plate 15. A slider 18 is fixedly arranged on the side of the clamping block 17 close to the mounting plate 15. A convex block 19 is fixedly arranged at the upper end of the slider 18 away from the clamping block 17. An arc - shaped chute 20 adapted to the convex block 19 is formed on the toothed plate 14 on the same side.

[0042] A semi - circular ring - shaped limit block 23 is installed at the bottom of the inner side of the mounting plate 15 by screws. A plurality of grooves adapted to the sliders 18 are formed on the limit block 23. A stop block 21 is arranged in the groove. The slider 18 covers the outside of the corresponding stop block 21, and a connecting spring 22 is fixedly arranged between the inner side wall of the end of the slider 18 away from the stop block 21 and the stop block 21.

[0043] In this embodiment, when it is necessary to clamp the steering column, the steering column is placed between the two open mounting plates 15. The second hydraulic rod 16 operates to rotate one side of the mounting plate 15 and the structures thereon. After fitting with the other side of the mounting plate 15, the second hydraulic rod 16 stops operating. The rotating block 12 is rotated to drive the second gear 13 to rotate, so that the two toothed plates 14 rotate in the two mounting plates 15, the chute 20 moves, squeezes the convex block 19, so that the slider 18 pushes the clamping block 17 towards the position where the steering column is located, and the connecting spring 22 is compressed until the clamping block 17 is in close contact with the steering column. Then stop rotating to realize the clamping of the steering column. This setting can clamp steering columns with different diameters and different parts thereof, with high applicability. Through the action of the first hydraulic rod 9, the inclination angle of the connecting plate 10 can be changed according to the test requirements, so as to change the inclination angle of the steering column clamped by the clamping member, with high flexibility.

[0044] In use, place a steering column between the upper and lower clamping members on the same side. The second hydraulic rod 16 operates to rotate the mounting plate 15 on one side and the structures thereon. After fitting with the mounting plate 15 on the other side, the second hydraulic rod 16 stops operating. Turn the rotating block 12, and the rotating block 12 separates from an elastic limiting member 40 below it, driving the second gear 13 to rotate, causing the two toothed plates 14 to rotate in the two mounting plates 15. The sliding groove 20 moves, squeezing the convex block 19, so that the slider 18 pushes the clamping block 17 towards the position of the steering column. The connecting spring 22 is compressed until the clamping block 17 is in close contact with the steering column. Stop turning to clamp the steering column. At this time, the rotating block 12 is engaged with another elastic limiting member 40 below it to limit the rotating block 12, thereby limiting the toothed plate 14 through the second gear 13 to prevent the toothed plate 14 from reversing due to the rebound force of the connecting spring 22.

[0045] The servo motor 6 drives the first gear 5 to rotate. The first gear 5 is meshed and connected with the toothed ring 4, causing the toothed ring 4 to drive the rotating column 2, the table 1 mounted on the rotating column 2, and the various structures mounted on the table 1 to rotate. After each 90-degree rotation, the servo motor 6 stops operating. Then, the linear motor 7 operates to drive the mounting bracket 8 and the structures mounted thereon to move into the corresponding test device. After reaching the position to be tested, the linear motor 7 stops operating, and the test can be carried out.

[0046] Example 2, please refer to Figures 8 - 11 , specifically, the difference from Example 1 is that the driving assembly includes a rotating mechanism and an up-and-down moving mechanism. The rotating mechanism is connected to the servo motor 6, the up-and-down moving mechanism is connected to the rotating mechanism, the up-and-down moving mechanism is arranged on one side of the moving assembly and is clamped and connected to it. The up-and-down moving mechanism makes the moving assembly operate by rotating the required angle through the rotating mechanism with the servo motor 6, so that the mounting bracket 8 and the structures thereon move horizontally back and forth.

[0047] The rotating mechanism includes two meshed fifth gears 36. First transmission members 35 are respectively installed on the two fifth gears 36. One fifth gear 36 is installed at the output end of the servo motor 6. The first transmission member 35 on this fifth gear 36 is installed at its upper end, and two coaxially arranged fourth gears 34 are installed at the lower end of this first transmission member 35. The two fourth gears 34 are rotatably connected and are installed on the base 3 through a bracket. The two fourth gears 34 are irregular gears, and the sides with teeth of the two fourth gears 34 are arranged in a staggered manner.

[0048] A first transmission member 35 on another fifth gear 36 is installed at its lower end, and the other end of the first transmission member 35 is installed at the lower end of the lower fourth gear 34. A sixth gear 37 is coaxially installed between the fifth gear 36 and the first transmission member 35 below it. The sixth gear 37 is an irregular gear, and a seventh gear 38 is intermittently meshed and connected to the side away from the servo motor 6. A second transmission member 39 is installed at the upper end of the seventh gear 38, and the other end of the second transmission member 39 is fixedly sleeved outside the rotating column 2.

[0049] The up and down moving mechanism includes a clamping block 29, a lead screw 30, a guide rod 31 and a fixing frame 32. The clamping block 29 is sleeved outside the lead screw 30 and the guide rod 31 and is threadedly connected to the lead screw 30. The lead screw 30 and the guide rod 31 are installed at the inner top of the fixing frame 32. The fixing frame 32 is in an inverted L shape and is fixed on the base 3. Two third gears 33 are coaxially arranged at the lower end of the lead screw 30.

[0050] The clamping block 29 includes a clamping part and a moving part. The clamping part is fixed on the side of the moving part close to the rotating column 2 and is formed by two upper and lower clamping plates, which are clamped on the moving assembly. The moving part is sleeved outside the lead screw 30 and the guide rod 31.

[0051] The upper third gear 33 is intermittently meshed and connected to the upper fourth gear 34, and the lower third gear 33 is intermittently meshed and connected to the lower fourth gear 34, which is used to drive the lead screw 30 to rotate forward and backward to realize the up and down movement of the clamping block 29. The radius of the fourth gear 34 is much larger than that of the third gear 33, and the thread pitch on the lead screw 30 is large, so as to realize the purpose of the lead screw 30 rotating multiple circles and the clamping block 29 moving up and down quickly.

[0052] The moving assembly includes an installation ring 28, a push rod 27, a fixing plate 26, a limiting rod 25 and an installation block 24. The installation ring 28 is sleeved outside the rotating column 2. The push rods 27 are symmetrically arranged on both sides of the installation ring 28, and the lower ends of the push rods 27 are rotatably connected to the outer side surface of the installation ring 28.

[0053] The installation blocks 24 are symmetrically fixed at the bottoms of two cross plates. The upper ends of the push rods 27 on the same side are rotatably installed at the bottom of the middle part of the installation block 24 on this side and penetrate through the table top 1.

[0054] The fixing plates 26 are symmetrically arranged on the table top 1 and are fixed at the upper edge of the table top 1. The limiting rods 25 are horizontally symmetrically arranged between the two fixing plates 26, and the pointing direction is the same as the sliding direction of the installation block 24. The limiting rods 25 penetrate through the installation blocks 24 at the bottoms of the two cross plates to realize the sliding guidance of the installation block 24.

[0055] One side of the mounting ring 28 is clamped with the clamping part in the clamping block 29. The mounting ring 28 drives the clamping block 29 to move up and down, so that the push rods 27 on both sides move upward to push the mounting block 24 and the cross plate, and move downward to pull the mounting block 24 and the cross plate, realizing the horizontal reciprocating movement of the cross plate and the structures thereon.

[0056] In this embodiment, the first transmission member 35 includes two transmission wheels of the same size and a transmission belt; the second transmission member 39 includes two transmission wheels of different sizes and a transmission belt. The larger transmission wheel is fixedly sleeved on the rotating column 2, the smaller transmission wheel is coaxially arranged with the seventh gear 38 and is installed on the base 3; one of the transmission wheels in the sixth gear 37, the fifth gear 36 thereon and the first transmission member 35 thereunder is coaxially arranged and installed on the base 3. The third gear 33 and the fourth gear 34 are also installed on the base 3. The guide rod 31 is fixedly installed at the inner top of the fixed frame 32.

[0057] The cross section of the mounting ring 28 is L-shaped. A long groove adapted to the push rod 27 is formed on the table top 1. When the upper mounting ring 28 moves upward, it pushes the push rod 27 upward. The upper end of the push rod 27 inclines outward to push the mounting block 24, thereby pushing the mounting frame 8 to move outward. When the mounting ring 28 moves downward, the push rod 27 pulls downward to pull the mounting frame 8 to move inward, realizing the horizontal reciprocating movement of the mounting frame 8.

[0058] When it is necessary to control the rotation of the rotating column 2, the table top 1 and the structures thereon, and after reaching the corresponding position, to control the horizontal movement of the mounting frame 8 and the structures thereon, the servo motor 6 operates to drive a fifth gear 36 at its upper end to rotate, so that the other fifth gear 36 rotates. This fifth gear 36 rotates to drive the fourth gear 34 above through a first transmission member 35 above. The other fifth gear 36 drives the fourth gear 34 below through a first transmission member 35 below to rotate in the opposite direction to the fourth gear 34 above. At the same time, the sixth gear 37 rotates and meshes with the seventh gear 38.

[0059] In the above driving process, taking one of the steering columns located at the position of the steering column durability test bench as an example, the sixth gear 37 is meshed and connected with the seventh gear 38, causing the seventh gear 38 to rotate 90 degrees. Through the second transmission member 39, the rotating column 2, the table 1 and the structures thereon are driven to rotate 90 degrees. The mounting ring 28 slides in the clamping block 29. After rotating 90 degrees, the sixth gear 37 is separated from the seventh gear 38. Both of the two fourth gears 34 rotate 90 degrees in different directions. At this time, the lower fourth gear 34 is about to be meshed and connected with the lower third gear 33, and the upper fourth gear 34 is separated from the upper third gear 33. The servo motor 6 continues to operate, causing the lower fourth gear 34 to be meshed and connected with the lower third gear 33, causing the lead screw 30 to rotate. Under the limiting and guiding of the guide rod 31, the clamping block 29 moves upward, driving the clamped mounting ring 28 to move upward, causing the push rod 27 to push the mounting block 24. Under the limiting and guiding of the limiting rod 25, the mounting block 24 drives the mounting frame 8 and the structures thereon to move into the steering column durability test bench. After moving to the position to be tested, the servo motor 6 stops operating for testing. At this time, the lower fourth gear 34 is separated from the lower third gear 33, and the upper fourth gear 34 approaches the upper third gear 33.

[0060] After the test is completed, the servo motor 6 continues to operate in the same direction. The upper fourth gear 34 is meshed and connected with the upper third gear 33, causing the lead screw 30 to rotate in the reverse direction. The clamping block 29 drives the mounting ring 28 to move downward, and the push rod 27 pulls the mounting block 24, causing the mounting frame 8 and the structures thereon to move back to their original positions until the upper fourth gear 34 is separated from the upper third gear 33. At this time, the sixth gear 37 approaches the seventh gear 38. The servo motor 6 continues to operate, and the sixth gear 37 is meshed and connected with the seventh gear 38, driving the rotating column 2, the table 1 and the structures thereon to continue rotating 90 degrees, causing the steering column that has undergone the non-damaging durability test to move to the next test position. Similarly, the other steering column symmetrically arranged with this steering column also moves to the next test position. By repeating the operation, multiple tests on the same steering column can be completed.

[0061] In use, for the installation part of the steering column, it is the same as that in Embodiment 1. After the steering column is installed, the servo motor 6 operates to drive a fifth gear 36 at its upper end to rotate, causing another fifth gear 36 to rotate. This fifth gear 36 drives a fourth gear 34 located above to rotate through a first transmission member 35 above it. The other fifth gear 36 drives the fourth gear 34 located below to rotate in the opposite direction to the fourth gear 34 above through the first transmission member 35 located below. At the same time, a sixth gear 37 rotates and meshes with a seventh gear 38, causing the seventh gear 38 to rotate by 90 degrees. Through a second transmission member 39, the rotating column 2, the table 1, and the structures thereon are driven to rotate by 90 degrees. After rotating by 90 degrees, the sixth gear 37 is separated from the seventh gear 38, and the rotating column 2 stops rotating.

[0062] At this time, the fourth gear 34 below is about to mesh with the third gear 33 below, and the fourth gear 34 above is away from the third gear 33 above. The servo motor 6 continues to operate, causing the fourth gear 34 below to mesh with the third gear 33 below, causing the lead screw 30 to rotate. Under the limit guidance of the guide rod 31, the clamping block 29 moves upward, driving the clamped mounting ring 28 upward, causing the push rod 27 to push the mounting block 24 to drive the mounting frame 8 and the structures thereon to move towards the steering column durability test bench. After moving to the position to be tested, the servo motor 6 stops operating for testing. At this time, the fourth gear 34 below is separated from the third gear 33 below, and the fourth gear 34 above approaches the third gear 33 above.

[0063] After the test is completed, the servo motor 6 operates, the fourth gear 34 above meshes with the third gear 33 above, the lead screw 30 rotates in the reverse direction, the clamping block 29 drives the mounting ring 28 to move downward, and the push rod 27 pulls the mounting block 24, causing the mounting frame 8 and the structures thereon to move back to their original positions until the fourth gear 34 above is separated from the third gear 33 above. At this time, the sixth gear 37 approaches the seventh gear 38. The servo motor 6 continues to operate, and the sixth gear 37 meshes with the seventh gear 38, driving the rotating column 2, the table 1, and the structures thereon to continue rotating by 90 degrees, causing the steering column that has undergone non-destructive durability testing to move to the next test position. Repeating the operation can complete the test.

[0064] Embodiment 3, a test method for the steering column performance test bench based on Embodiment 1 or Embodiment 2, referring to Figure 13 , includes the following steps: obtaining the test parameter set stored in the data repository, and based on the test parameter set, obtaining the test results of each test; based on the test results of each test, obtaining the passing rate of the test performance of each test; based on the passing rate of the test performance of each test, obtaining the comprehensive performance of the steering column.

[0065] The test parameter set includes noise and vibration test parameters, durability test parameters, environmental resistance test parameters, and corrosion test parameters; the noise and vibration test parameters include parameters for each part, and the part parameters include noise spectrum, vibration amplitude, and vibration frequency. Based on the parameters for each part, the noise and vibration test values for each part are analyzed and obtained.

[0066] The calculation formula for the noise and vibration test value is as follows: ; In the formula: is the noise and vibration test value at the vibration frequency , is the actual pressure value of the noise at the vibration frequency , is the vibration amplitude at the vibration frequency , is the intensity of the noise, p is the actual pressure value of the noise, is the reference sound pressure, is the initial vibration amplitude, A is the vibration amplitude, F is the external force, k is the system stiffness, is the frequency response function, is the displacement response value at the vibration frequency , is the external force at the vibration frequency , m is the mass of the steering attention, c is the damping coefficient, is the vibration frequency, j is the imaginary unit, and lg represents the logarithm to the base 10.

[0067] Based on the noise and vibration test values of each part, it is judged whether there is abnormal noise in each part: the noise and vibration test values of each part are compared with the noise and vibration test thresholds of the corresponding parts in turn. If the noise and vibration test value is greater than the noise and vibration test threshold, there is no abnormal noise; if the noise and vibration test value is not greater than the noise and vibration test threshold, there is abnormal noise, and the position is recorded; based on the number of abnormal noise positions, the qualification rate of the test performance of the noise and vibration test is analyzed.

[0068] The calculation formula for the qualification rate of the test performance of the noise and vibration test is as follows: ; In the formula: is the qualification rate of the test performance of the noise and vibration test, is the number of parts with abnormal noise, is the total number of test parts.

[0069] The durability test parameters include stress amplitude, number of cycles, material constant, and material fatigue index. Based on the durability test parameters, the cumulative damage value is obtained, and the predicted total life is analyzed.

[0070] The calculation formula for predicting the total life is: ; In the formula: is the predicted total life, is the remaining life, is the number of cycles that the material can withstand at (determined by the S-N curve), is the i-th stress amplitude, C is the material constant, cp is the material fatigue index, D is the cumulative damage value (calculated based on Miner), is the actual number of cycles of the material at (in the), is the acting force of the material at (in the), is the cross-sectional area, i is the stress amplitude number, and n is the total number of stress amplitudes.

[0071] The S-N curve is a curve that describes the fatigue life of a material under cyclic loading, indicating the number of cycles (N) that the material can withstand at different stress amplitudes (S). The S-N curve is usually obtained by conducting fatigue tests on the material. The Miner linear cumulative damage theory is a theory used to evaluate the fatigue life of a material under variable amplitude loading. It is assumed that the damage of the material at different stress levels can be linearly accumulated, and when the cumulative damage reaches 1, the material undergoes fatigue failure.

[0072] Compare the predicted total life with the predicted life threshold. If the predicted total life is greater than the predicted life threshold, the pass rate of the test performance of the durability test is 100%; if the predicted total life is not greater than the predicted life threshold, analyze and obtain the pass rate of the test performance of the durability test.

[0073] The calculation formula for the pass rate of the test performance of the durability test is: ; In the formula: is the pass rate of the test performance of the durability test, is the predicted life threshold, is the predicted total life.

[0074] The environmental resistance test parameters include the temperature range value, humidity range value, material expansion coefficient, material moisture absorption rate, and analyze and obtain the comprehensive expansion value.

[0075] The calculation formula for the comprehensive expansion value is: ; In the formula: is the change value of the material length under temperature change, is the thermal expansion coefficient of the material, is the initial length of the material, is the temperature change value, is the material length change value of the material under humidity change, is the hygroscopic expansion coefficient of the material, is the humidity change value, is the comprehensive expansion value.

[0076] The comprehensive expansion value is successively subtracted from each reference expansion value stored in the data repository to obtain the absolute value of the expansion value difference. The qualified rate of the test performance of the environmental resistance test corresponding to the reference expansion value corresponding to the smallest absolute value of the expansion value difference is the qualified rate of the test performance of the environmental resistance test of the comprehensive expansion value.

[0077] The corrosion test parameters include corrosion duration, corrosion area, and weight loss, and the corrosion rate is obtained through analysis.

[0078] The calculation formula for the corrosion rate is: ; In the formula: R is the corrosion rate, W is the weight loss value, is the corrosion area, and t is the corrosion duration; The corrosion rate is successively subtracted from each reference corrosion rate stored in the data repository to obtain the absolute value of the corrosion rate difference. The qualified rate of the test performance of the corrosion test corresponding to the reference corrosion rate corresponding to the smallest absolute value of the corrosion rate difference is the qualified rate of the test performance of the corrosion test of the corrosion rate.

[0079] The qualified rates of the test performance of the noise and vibration test, the durability test, the environmental resistance test, and the corrosion test are recorded as test performance data; the test performance data is compared with the test performance reference data of each reference steering column stored in the data repository. Each parameter in the test performance data is subtracted from the corresponding reference parameter in each group of test performance reference data to obtain the absolute value of the comprehensive test performance difference. The comprehensive performance of the steering column corresponding to the test performance reference data corresponding to the smallest absolute value of the comprehensive test performance difference is the comprehensive performance of the steering column of the current test performance data.

[0080] Analysis of the noise spectrum and vibration frequency can accurately locate the abnormal sound source, assist in quickly solving the problem of abnormal sound in the steering system, reduce noise and vibration, improve the NVH performance of the vehicle, and ensure driving comfort. Fatigue life prediction ensures that the steering column will not pose a safety hazard due to fatigue failure during long-term use. Analysis of the cumulative damage value provides data support for the design optimization of the steering column and extends its service life. Environmental resistance testing ensures the performance stability of the steering column in extreme environments and avoids performance degradation caused by temperature or humidity changes. Analysis of the expansion and moisture absorption performance optimizes material selection and improves the environmental adaptability of the steering column. Corrosion testing ensures the long-term reliability of the steering column in a corrosive environment and avoids performance degradation or failure caused by corrosion. Analysis of the corrosion rate optimizes material selection and improves the corrosion resistance of the steering column.

[0081] Integrating the pass rates of various tests provides a comprehensive performance assessment to ensure the reliability of the steering column under various working conditions. Comprehensive performance assessment provides data support for the design optimization of the steering column, promoting product iteration and improvement. Quantitative assessment of the comprehensive performance provides clear performance criteria and avoids errors caused by subjective judgment.

[0082] Comprehensive performance testing ensures the high quality of the steering column in design, manufacturing, and use. Detecting problems through testing in the design and development stage can avoid large-scale failures during mass production or use, reducing maintenance and recall costs. Durability testing and environmental resistance testing ensure the safety of the steering column during long-term use and in extreme environments, reducing safety accidents caused by failures. Accumulation and analysis of test data provide data support for the design optimization of the steering column, promoting technological progress and product iteration.

[0083] The formula in this embodiment can be dimensionless processed during calculation to simplify the calculation.

[0084] In addition to the above test methods, it is also possible to use conventional test methods for testing based on the steering column performance test bench of Embodiment 1 or Embodiment 2, such as static strength testing, connection stiffness testing, locking performance testing, etc.

Claims

1. A steering column performance test bench, characterized in that, Comprising: A detection table, which is a rotatable support frame with a circular upper surface; A servo motor (6), which is installed at an outer position on the inner bottom surface of the detection table by screws; A drive assembly, which is located in the middle part of the detection table and is connected to the servo motor (6) for driving the upper surface of the detection table to rotate; A mounting frame (8), which is symmetrically arranged above the detection table, and a first hydraulic rod (9) is hinged on the mounting frame (8). The other end of the first hydraulic rod (9) and a lower position on the outer side of the mounting frame (8) are hinged to the same connecting plate (10). Two clamping members are arranged up and down on the outer side of the connecting plate (10), and the two clamping members on the same side are used in cooperation; A moving assembly, which is located on the upper surface of the detection table and is arranged at the bottom of the mounting frame (8) for driving the mounting frame (8), the first hydraulic rod (9) above it, the clamping members and the steering column to move horizontally back and forth; Around the circumference of the detection table, a steering column durability test bench, a noise and vibration test device, an environmental resistance test device and a corrosion test device are sequentially placed in a ring shape.

2. The steering column performance test bench according to claim 1, characterized in that: The detection table includes a tabletop (1), a rotating column (2), and a base (3). The tabletop (1), the rotating column (2), and the base (3) are arranged from top to bottom in sequence. The lower end of the rotating column (2) is rotatably connected to the base (3), and the servo motor (6) is installed on the base (3); The mounting frame (8) includes a horizontal plate and a frame body part. The frame body part is installed at the upper end of the horizontal plate by screws, and the horizontal plate is installed on the moving assembly.

3. The steering column performance test bench according to claim 2, wherein: The drive assembly includes a first gear (5) and a toothed ring (4) meshed with it. The first gear (5) is installed at the output end of the servo motor (6), and the toothed ring (4) is sleeved outside the rotating column (2) and is fixedly connected to the rotating column (2).

4. The steering column performance test bench according to claim 2, characterized in that: The moving assembly includes two linear motors (7), which are installed between the tabletop (1) and the horizontal plate and can drive the horizontal plate and the structures on it to move horizontally back and forth.

5. The steering column performance test bench according to claim 2, wherein: The drive assembly includes a rotating mechanism and an up-and-down moving mechanism. The rotating mechanism is connected to the servo motor (6), the up-and-down moving mechanism is connected to the rotating mechanism, the up-and-down moving mechanism is arranged on one side of the moving assembly and is clamped and connected to it. The up-and-down moving mechanism makes the moving assembly operate by rotating the required angle with the servo motor (6) through the rotating mechanism, so that the mounting frame (8) and the structures on it move horizontally back and forth; The rotating mechanism includes two meshed fifth gears (36). First transmission members (35) are respectively installed on the two fifth gears (36). One fifth gear (36) is installed at the output end of the servo motor (6). The first transmission member (35) on this fifth gear (36) is installed at its upper end, and two coaxially arranged fourth gears (34) are installed at the lower end of this first transmission member (35). The two fourth gears (34) are rotatably connected between them and are installed on the base (3) through a frame. The two fourth gears (34) are irregular gears, and the sides with teeth of the two fourth gears (34) are arranged in a staggered manner; A first transmission member (35) on another fifth gear (36) is installed at its lower end, and the other end of the first transmission member (35) is installed at the lower end of the fourth gear (34) below. A sixth gear (37) is coaxially installed between the fifth gear (36) and the first transmission member (35) below it. The sixth gear (37) is an irregular gear, and a seventh gear (38) is intermittently meshed and connected to the side away from the servo motor (6). A second transmission member (39) is installed at the upper end of the seventh gear (38), and the other end of the second transmission member (39) is fixedly sleeved outside the rotating column (2). The vertical movement mechanism includes a clamping block (29), a lead screw (30), a guide rod (31) and a fixed frame (32). The clamping block (29) is sleeved outside the lead screw (30) and the guide rod (31), and is threadedly connected to the lead screw (30). The lead screw (30) and the guide rod (31) are installed at the inner top of the fixed frame (32). The fixed frame (32) is in an inverted L shape and is fixed on the base (3). Two third gears (33) are coaxially arranged at the lower end of the lead screw (30). The clamping block (29) includes a clamping part and a moving part. The clamping part is fixed on the side of the moving part close to the rotating column (2), and is formed by two upper and lower clamping plates, which are clamped on the moving assembly. The moving part is sleeved outside the lead screw (30) and the guide rod (31). The upper third gear (33) is intermittently meshed and connected to the upper fourth gear (34), and the lower third gear (33) is intermittently meshed and connected to the lower fourth gear (34), which is used to drive the lead screw (30) to rotate forward and backward, so as to realize the up and down movement of the clamping block (29).

6. The steering column performance test bench according to claim 5, wherein: The moving assembly includes a mounting ring (28), a push rod (27), a fixing plate (26), a limiting rod (25) and a mounting block (24). The mounting ring (28) is sleeved outside the rotating column (2). The push rods (27) are symmetrically arranged on both sides of the mounting ring (28), and the lower ends of the push rods (27) are rotatably connected to the outer side surface of the mounting ring (28). The mounting blocks (24) are symmetrically fixed at the bottoms of the two cross plates. The upper ends of the push rods (27) on the same side are rotatably installed at the bottom of the middle part of the mounting block (24) on this side and penetrate through the table top (1). The fixing plates (26) are symmetrically arranged on the table top (1) and are fixed at the upper edge of the table top (1). The limiting rods (25) are horizontally symmetrically arranged between the two fixing plates (26), and the pointing direction is the same as the sliding direction of the mounting block (24). The limiting rods (25) penetrate through the mounting blocks (24) at the bottoms of the two cross plates to realize the sliding guidance of the mounting block (24). One side of the mounting ring (28) is clamped with the clamping part in the clamping block (29). The mounting ring (28) drives it to move up and down through the clamping block (29), so that the push rods (27) on both sides push the mounting block (24) and the cross plate upward and pull the mounting block (24) and the cross plate downward.

7. The steering column performance test bench according to claim 1, wherein: The clamping member includes two symmetrically arranged toothed plates (14) and two symmetrically arranged mounting plates (15). The mounting plates (15) on the same side are arranged below the toothed plates (14). The toothed plate (14) includes a toothing portion and a connecting portion. The connecting portion is arranged at the outer part of the bottom of the toothing portion, and the connecting portion extends into the mounting plate (15) and is slidably connected thereto. Both the toothed plate (14) and the mounting plate (15) are semi-circular rings; The toothing portion in the toothed plate (14) on one side is meshed and connected with a second gear (13). The second gear (13) is rotatably connected with a connecting block (11). The mounting plate (15) below the toothed plate (14) on this side is fixedly arranged at the inner bottom of the connecting block (11). A rotating block (12) is installed at the upper end of the second gear (13). The rotating block (12) is arranged above the connecting block (11). One end of the mounting plate (15) on the other side is rotatably installed in the connecting block (11), forming a clip shape that can be opened and closed on one side with the mounting plate (15) fixed in the connecting block (11). A second hydraulic rod (16) is hingedly installed between the outer side of the rotatable mounting plate (15) and the side wall of the connecting block (11). The connecting block (11) is fixedly arranged on the connecting plate (10); Two elastic limit members (40) are fixedly arranged on the connecting block (11) for limiting the rotating block (12). A hemispherical groove adapted to the elastic limit member (40) is formed at the bottom of the rotating block (12); Clamping blocks (17) are linearly arranged along the semi-circumference on the inner side of the mounting plate (15). A sliding block (18) is fixedly arranged on the side of the clamping block (17) close to the mounting plate (15). A convex block (19) is fixedly arranged at the part of the upper end of the sliding block (18) far from the clamping block (17). An arc-shaped sliding groove (20) adapted to the convex block (19) is formed on the toothed plate (14) on the same side; A semi-circular ring-shaped limit block (23) is installed at the inner bottom of the mounting plate (15) by screws. A plurality of grooves adapted to the sliding block (18) are formed on the limit block (23). A stop block (21) is arranged in the groove. The sliding block (18) covers the outside of the corresponding stop block (21), and a connecting spring (22) is fixedly arranged between the inner side wall of the end of the sliding block (18) far from the stop block (21) and the stop block (21).

8. A test method for a steering column performance test bench, applied to the steering column performance test bench according to any one of claims 1-7, characterized in that, Including the following steps: Obtain the test parameter set stored in the data repository, and based on the test parameter set, obtain the test results of each test; Based on the test results of each test, obtain the passing rate of the test performance of each test; Based on the passing rate of the test performance of each test, obtain the comprehensive performance of the steering column.

9. The test method of the steering column performance test bench according to claim 8, characterized in that Obtaining the passing rate of the test performance of each test specifically includes the following steps: The test parameter set includes noise and vibration test parameters, durability test parameters, environmental resistance test parameters, and corrosion test parameters; The noise and vibration test parameters include parameters of each part. The part parameters include noise spectrum, vibration amplitude, and vibration frequency. Based on the parameters of each part, the noise and vibration test values of each part are analyzed; The calculation formula for the noise and vibration test value is: ； Where: is the noise and vibration test value at the vibration frequency , is the actual pressure value of the noise at the vibration frequency , is the vibration amplitude at the vibration frequency , is the intensity of the noise, p is the actual pressure value of the noise, is the reference sound pressure, is the initial vibration amplitude, A is the vibration amplitude, F is the external force, k is the system stiffness, is the frequency response function, is the displacement response value at the vibration frequency , is the external force at the vibration frequency , m is the mass of the steering concern, c is the damping coefficient, is the vibration frequency, j is the imaginary unit; Based on the noise and vibration test values of each part, determine whether there is abnormal noise in each part: Compare the noise and vibration test values of each part with the noise and vibration test thresholds of the corresponding parts in sequence. If the noise and vibration test values are greater than the noise and vibration test thresholds, there is no abnormal noise. If the noise and vibration test values are not greater than the noise and vibration test thresholds, there is abnormal noise, and the position is recorded. Based on the number of abnormal noise positions, analyze and obtain the pass rate of the test performance of the noise and vibration test. The durability test parameters include stress amplitude, number of cycles, material constant, and material fatigue index. Based on the durability test parameters, obtain the cumulative damage value and analyze and obtain the predicted total life. The calculation formula for the predicted total life is: ； Wherein: is the predicted total life is the remaining life is the number of cycles that the material can withstand at ; is the i-th stress amplitude, C is the material constant, cp is the material fatigue index, D is the cumulative damage value is the actual number of cycles of the material at ; is the acting force of the material at ; is the cross-sectional area, i is the stress amplitude number, and n is the total number of stress amplitudes; Compare the predicted total life with the predicted life threshold. If the predicted total life is greater than the predicted life threshold, the pass rate of the test performance of the durability test is 100%. If the predicted total life is not greater than the predicted life threshold, analyze and obtain the pass rate of the test performance of the durability test. The environmental resistance test parameters include temperature range value, humidity range value, material expansion coefficient, and material moisture absorption rate, and analyze and obtain the comprehensive expansion value. The calculation formula for the comprehensive expansion value is: ； In the formula: is the change value of the material length under temperature change, is the coefficient of thermal expansion of the material, is the initial length of the material, is the temperature change value, is the change value of the material length under humidity change, is the hygroscopic expansion coefficient of the material, is the humidity change value, is the comprehensive expansion value; Subtract the comprehensive expansion value from each reference expansion value stored in the data repository in sequence to obtain the absolute value of the expansion value difference. The pass rate of the test performance of the environmental resistance test corresponding to the reference expansion value corresponding to the smallest absolute value of the expansion value difference is the pass rate of the test performance of the environmental resistance test of the comprehensive expansion value. The corrosion test parameters include corrosion duration, corrosion area, and weight loss, and analyze and obtain the corrosion rate. The calculation formula for the corrosion rate is: ； Where: R is the corrosion rate, W is the weight loss value, is the corrosion area, and t is the corrosion duration; Subtract the corrosion rate from each reference corrosion rate stored in the data repository in sequence to obtain the absolute value of the corrosion rate difference. The pass rate of the test performance of the corrosion test corresponding to the reference corrosion rate corresponding to the smallest absolute value of the corrosion rate difference is the pass rate of the test performance of the corrosion test of the corrosion rate.

10. The test method of the steering column performance test bench according to claim 8, characterized in that, Obtain the comprehensive performance of the steering column, specifically including the following steps: Record the pass rates of the test performance of the noise and vibration test, durability test, environmental resistance test, and corrosion test as test performance data. Compare the test performance data with the test performance reference data of each reference steering column stored in the data repository. Subtract the corresponding reference parameters in each group of test performance reference data from the parameters in the test performance data to obtain the absolute value of the comprehensive test performance difference. The comprehensive performance of the steering column corresponding to the reference steering column corresponding to the test performance reference data corresponding to the smallest absolute value of the comprehensive test performance difference is the comprehensive performance of the steering column of the current test performance data.

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