Steering system bumpy road condition simulation test bench and test method

Abstract

This invention discloses a test bench and method for simulating bumpy road conditions in a steering system. The test bench includes two symmetrically arranged vibration sections with identical structures. Each vibration section includes a support frame, comprising a base and a vertical frame formed on the base; a drive motor, which passes through the vertical frame and is fixed to the base, and whose output drives a slide table to reciprocate; a slide table, whose reciprocating motion of its bearing drives an amplitude cam to generate excitation motion; and an amplitude cam, which drives a vibrating element mounted on the vertical frame to generate vibration. This invention uses two independent drive motors to drive the amplitude cams on both sides to rotate, causing the slide table to move reciprocally at high frequency. Combined with upper and lower damping springs to simulate the damping characteristics of the chassis bushings, it accurately reproduces the road excitation transmitted independently by the left and right tires. Multi-mode vibration excitation is achieved through programmable control, meeting the NVH testing requirements of the steering system.

Description

Technical Field

[0001] This invention relates to the automotive field, and in particular to a test bench for simulating bumpy road conditions in a steering system. Background Technology

[0002] The steering system is a core safety component of a car chassis, directly affecting vehicle stability, handling, and ride safety. With the rapid popularization of new energy vehicles, the trends towards lightweight, highly integrated, and low-noise vehicles are evident, and users' demands for ride comfort and smoothness are constantly increasing. This makes the NVH (noise, vibration, and harshness) transmission characteristics of the steering system increasingly critical. Factors such as high-frequency vibrations in the electric drive system of new energy vehicles, motor torque fluctuations, and battery pack vibration transmission further exacerbate the vibration transmission risks in the steering system, placing higher and more stringent requirements on its NVH performance. Therefore, conducting accurate and efficient vibration simulation testing during the development phase is particularly important.

[0003] Currently, the industry mainly relies on two technical methods for vibration testing of steering systems under bumpy road conditions, but both have significant shortcomings: First, a general vibration table is used to apply vibration excitation to the entire steering system. This method is a synchronous vibration across the entire range. The excitation mode is single and the degree of freedom is limited. It cannot reproduce the real working condition of the left and right wheels contacting the bumpy road surface and independently transmitting vertical / lateral excitation during actual vehicle driving. As a result, the test excitation is significantly different from the vibration mode actually transmitted to the steering system by the whole vehicle, and the test results have limited reference value. Second, the whole vehicle road surface simulation test is carried out using a whole vehicle-level four-column vibration test bench. Although this solution can fully reproduce the real road surface excitation and has high test accuracy, it requires the investment of whole vehicles, dedicated sites, large vibration equipment and supporting manpower. The test cycle is long, the cost is high, the resource consumption is large, and the economy and timeliness are poor. It is difficult to meet the efficient testing needs of early development, rapid iteration and batch comparative test of steering system.

[0004] In summary, existing steering system bumpy road condition simulation tests generally suffer from prominent defects such as inability to accurately simulate independent excitation of the left and right tires, low working condition fit, high testing costs, long cycles, and low efficiency. The industry urgently needs a bumpy road condition simulation test solution that is simple in structure, cost-controllable, closely fits the working conditions of real vehicles, and can be carried out quickly, so as to efficiently complete the NVH performance evaluation and optimization of steering systems. Summary of the Invention

[0005] The summary of this invention introduces a series of simplified concepts, all of which are simplifications of existing technologies in the field, and will be further explained in detail in the detailed description section. This summary is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] This invention addresses the shortcomings of existing technologies and aims to solve the following technical problems: 1. Ordinary vibration tables cannot simulate independent excitation of the left and right tires; 2. The four-pillar test for the whole vehicle is costly and inefficient; 3. It is difficult to accurately reproduce the road excitation and chassis damping characteristics of a real vehicle on a subsystem test bench.

[0007] To solve the above-mentioned technical problems, the present invention provides a steering system bumpy road condition simulation test bench, comprising: two vibration parts with identical structures arranged symmetrically side by side, each vibration part comprising: The support frame includes: a base 1.1 and a vertical frame 1.2 formed on the base 1.1; The drive motor 2 passes through the vertical frame 1.2 and is fixed to the base 1.1. Its output end drives the slide table 3 to reciprocate. The slide table 3, whose slide table bearing reciprocates, drives the amplitude cam 4 to generate excitation motion; The amplitude cam 4 drives the vibrating element mounted on the vertical frame 1.2 to vibrate.

[0008] Optionally, further improvements to the aforementioned steering system bumpy road condition simulation test bench may include: The controller enables the drive motor 2 to drive the slide table to move rapidly left and right according to the set waveform, so that it meets the vibration frequency.

[0009] Optionally, the steering system bumpy road condition simulation test bench can be further improved, with a vibration frequency range of less than or equal to 5Hz.

[0010] Optionally, the steering system bumpy road condition simulation test bench can be further improved, and the vibration components include: The contact plate, which makes contact with the amplitude cam, is fixedly connected to the lower end of the damping spring; A damping spring, with its upper and lower ends passing through the vertical frame 1.2, and its middle part fixed in the vertical frame 1.2; The mounting plate is fixedly connected to the upper damping spring end and is used to mount the sample.

[0011] Optionally, the steering system bumpy road condition simulation test bench can be further improved, with an independent controller set for each vibration section.

[0012] Optionally, the steering system bumpy road condition simulation test bench can be further improved so that the two vibration parts can be driven independently, forming dual-axis same-frequency drive, dual-axis different-frequency drive and single-axis variable-frequency drive.

[0013] To solve the above-mentioned technical problems, the present invention provides a method for simulating bumpy road conditions in a steering system, which is implemented using the steering system bumpy road condition simulation test bench described in any one of the above-mentioned methods, and includes the following steps: 1) Select a damping spring and install the sample onto the mounting plate; 2) Set the driving motor operating parameters through controller programming; 3) The drive motor drives the slide table to reciprocate, which in turn drives the amplitude cam to rotate, generating excitation and causing the sample to vibrate; 4) Collect vibration data of the sample or conduct subjective vibration assessment.

[0014] The working principle of the present invention is explained below based on the above technical solution; This invention uses two independent drive motors to drive the two side amplitude cams to rotate, which in turn drive the slide to move back and forth at high frequency. With the help of upper and lower damping springs to simulate the damping characteristics of the chassis rubber bushing, it accurately reproduces the road excitation transmitted independently by the left and right tires. Through programmable control, it realizes multi-mode vibration excitation and meets the NVH test requirements of the steering system.

[0015] Based on the above technical solution and working principle, the present invention can achieve at least the following technical effects compared with the prior art; 1. The present invention adopts a drive scheme with dual independent motors and an independent cam structure, which can realize independent excitation of the left and right tires. The motor action is controlled by the controller to simulate different vibration frequencies, thus filling the gap in the prior art.

[0016] 2. This invention uses a drive scheme with dual independent motors and an independent cam structure to replace the four-pillar test of the whole vehicle. It does not require the resources of the whole vehicle, making the test convenient, economical, and achieving low cost and high efficiency.

[0017] 3. The present invention adopts a drive scheme with dual independent motors and independent cam structure, which can support single-axis, dual-axis same frequency / different frequency, and single-axis variable frequency drive, adapt to multiple test scenarios, and has flexible drive modes.

[0018] 4. This invention uses a damping spring to simulate the characteristics of the chassis rubber bushing, and the frequency within 5Hz matches the actual vehicle, making the data more reliable and the test more realistic. Attached Figure Description

[0019] The accompanying drawings are intended to illustrate the general characteristics of the methods, structures, and / or materials used in specific exemplary embodiments of the invention, supplementing the description in the specification. However, the drawings are schematic diagrams not drawn to scale and may not accurately reflect the precise structural or performance characteristics of any of the given embodiments. The drawings should not be construed as limiting or restricting the range of numerical values ​​or properties covered by exemplary embodiments of the invention. The invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a schematic diagram of a preferred embodiment of the vibration element of the present invention.

[0022] Explanation of reference numerals in the attached figures: Base 1.1; Vertical frame 1.2; Drive motor 2; Slide 3; Amplitude Cam 4; Contact plate 5.1; Damping spring 5.2; Mounting plate 5.3; Sample 6. Detailed Implementation

[0023] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can fully understand other advantages and technical effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and various details in this specification can also be applied based on different viewpoints, with various modifications or changes made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. The following exemplary embodiments of the present invention can be implemented in many different forms and should not be construed as being limited to the specific embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art. It should be understood that when an element is referred to as "connected" or "combined" to another element, the element can be directly connected or combined to the other element, or there may be intermediate elements. The difference is that when an element is referred to as "directly connected" or "directly combined" to another element, there are no intermediate elements. Throughout the drawings, the same reference numerals always denote the same elements.

[0024] First embodiment; This invention provides a test bench for simulating bumpy road conditions in a steering system, comprising: two vibration units with identical structures arranged symmetrically side by side, for reference. Figure 1 As shown, each vibrating section includes: The support frame includes: a base 1.1 and a vertical frame 1.2 formed on the base 1.1; The drive motor 2 passes through the vertical frame 1.2 and is fixed to the base 1.1. Its output end drives the slide table 3 to reciprocate. The slide table 3, whose slide table bearing reciprocates, drives the amplitude cam 4 to generate excitation motion; The amplitude cam 4 drives the vibrating element mounted on the vertical frame 1.2 to vibrate.

[0025] Optionally, the first embodiment described above can be further improved by adding a controller; The controller causes the drive motor 2 to drive the slide table to move rapidly left and right according to the set waveform, so that it meets the vibration frequency.

[0026] The output power of the drive motor and the resulting vibration frequency can be obtained through calibration, and the vibration frequency range is usually less than or equal to 5Hz.

[0027] Preferred, Reference Figure 2 As shown, a preferred embodiment of the vibrating element of the present invention includes: Contact plate 5.1, which makes contact with amplitude cam 4, is fixedly connected to the lower end of damping spring 5.2; A damping spring, with its upper and lower ends passing through the vertical frame 1.2, and its middle part fixed in the vertical frame 1.2; Mounting plate 5.3 is fixedly connected to the upper end of the nylon spring 5.2 and is used to mount the sample.

[0028] Preferably, each vibrating part is equipped with an independent controller, and the two vibrating parts can be driven independently, forming dual-axis same-frequency drive, dual-axis different-frequency drive, and single-axis variable-frequency drive.

[0029] Second embodiment; This invention provides a method for simulating bumpy road conditions in a steering system, which is implemented using the bumpy road condition simulation test bench for a steering system described in the first embodiment, and includes the following steps: 1) Select a damping spring and install the sample onto the mounting plate; 2) Set the driving motor operating parameters through controller programming; 3) The drive motor drives the slide table to reciprocate, which in turn drives the amplitude cam to rotate, generating excitation and causing the sample to vibrate; 4) Collect vibration data of the sample or conduct subjective vibration assessment.

[0030] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will also be understood that, unless explicitly defined herein, terms such as those defined in a general dictionary shall be interpreted as having the meaning consistent with their meaning in the relevant field context, and not as having an idealized or overly formal meaning.

[0031] The present invention has been described in detail above through specific embodiments and examples, but these are not intended to limit the invention. Many modifications and improvements can be made by those skilled in the art without departing from the principles of the invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A test bench for simulating bumpy road conditions in a steering system, characterized in that, include: Two identical, symmetrically arranged vibrating parts are each comprising: The support frame includes: a base (1.1) and a vertical frame (1.2) formed on the base (1.1). The drive motor (2) passes through the vertical frame (1.2) and is fixed to the base (1.1). Its output end drives the slide (3) to reciprocate. The slide table (3) and its slide table bearing reciprocate to drive the amplitude cam (4) to generate excitation motion; An amplitude cam (4) drives a vibrating element mounted on a vertical frame (1.2) to vibrate.

2. The steering system bumpy road condition simulation test bench as described in claim 1, characterized in that, Also includes: The controller enables the drive motor (2) to drive the slide table to move rapidly left and right according to the set waveform, so that it meets the vibration frequency.

3. The steering system bumpy road condition simulation test bench as described in claim 2, characterized in that: The vibration frequency range is less than or equal to 5Hz.

4. The steering system bumpy road condition simulation test bench as described in claim 1, characterized in that, Vibrating components include: The contact plate, which makes contact with the amplitude cam, is fixedly connected to the lower end of the damping spring; A damping spring, with its upper and lower ends extending out of the vertical frame (1.2), and its middle part fixed in the vertical frame (1.2); The mounting plate is fixedly connected to the upper damping spring end and is used to mount the sample.

5. The steering system bumpy road condition simulation test bench as described in claim 2, characterized in that: Each vibrating part is equipped with an independent controller.

6. The steering system bumpy road condition simulation test bench as described in claim 5, characterized in that: The two vibrating parts can be driven independently, forming dual-axis same-frequency drive, dual-axis different-frequency drive, and single-axis variable-frequency drive.

7. A method for simulating bumpy road conditions in a steering system, implemented using the bumpy road condition simulation test bench for a steering system as described in any one of claims 1-6, characterized in that, Includes the following steps: 1) Select a damping spring and install the sample onto the mounting plate; 2) Set the driving motor operating parameters through controller programming; 3) The drive motor drives the slide table to reciprocate, which in turn drives the amplitude cam to rotate, generating excitation and causing the sample to vibrate; 4) Collect vibration data of the sample or conduct subjective vibration assessment.

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