Drive shaft starting abnormal noise test device and method

Abstract

The application discloses a kind of driving shaft starting abnormal sound test device and method, including driving device, wheel hub detection unit and data processing center;The driving device is used to output torque T3 according to test requirement, the output shaft of this driving device is used to connect with the slip joint of measured driving shaft;The wheel hub detection unit includes wheel hub and vibration accelerator sensor;The wheel hub is used to simulate real vehicle assembly state, and the wheel hub is used to connect with the fixed joint of driving shaft;The vibration accelerator sensor is used to collect data, and the vibration accelerator sensor is installed on the wheel hub;The data processing center is connected with vibration accelerator sensor, and the data processing center is used to store and process the data detected, and output the corresponding relationship between acceleration and time.The application can determine whether driving shaft exists starting abnormal sound, and can evaluate abnormal sound degree.

Description

Technical Field

[0001] This invention belongs to the field of vehicle testing technology, specifically relating to a test device and method for abnormal noise during drive shaft start-up. Background Technology

[0002] When the vehicle starts rapidly or reverses, one or more "clunking" noises may be heard from the wheel wells. The noise originates at the mating face between the drive shaft retaining joint and the wheel hub bearing. This is caused by the axial force generated by the assembly torque locking the drive shaft and wheel hub. This axial force creates static friction at the mating face. When starting with high throttle, the engine's output torque can overcome this friction. However, if there is a gap or elastic deformation at the mating face, slippage occurs, causing noise. This problem can occur at the initial mileage of the vehicle or at higher mileage, and is a durability-related NVH (Noise, Vibration, and Harshness) issue. While solutions exist to improve the starting noise problem, there are currently no bench tests or corresponding methods for rapid verification. Road testing is the only option, resulting in long verification cycles and high costs, hindering the rapid verification and implementation of optimized solutions.

[0003] Therefore, it is necessary to develop a new test device and method for abnormal noise during drive shaft start-up. Summary of the Invention

[0004] The purpose of this invention is to provide a test device and method for abnormal noise during drive shaft start-up, which can determine whether abnormal noise exists in the drive shaft during start-up and can assess the degree of abnormal noise.

[0005] In a first aspect, the drive shaft starting noise test device of the present invention includes a drive device, a wheel hub detection unit and a data processing center;

[0006] The drive device is used to output torque T3 according to the test requirements, and the output shaft of the drive device is used to connect with the sliding joint of the drive shaft under test.

[0007] The wheel hub detection unit includes a wheel hub and a vibration accelerometer sensor;

[0008] The wheel hub is used to simulate the assembly state of a real vehicle, and the wheel hub is used to connect with the fixed joint of the drive shaft;

[0009] The vibration accelerator sensor is used to collect data and is mounted on the wheel hub.

[0010] The data processing center is connected to the vibration accelerometer sensor. The data processing center is used to store and process the detected data and output the correspondence between acceleration and time.

[0011] Optionally, the driving device is a servo motor.

[0012] Secondly, the method for testing abnormal noise during drive shaft startup according to the present invention uses the drive shaft abnormal noise testing device as described in the present invention, and the method includes the following steps:

[0013] S1: Obtain test input parameters: Obtain the drive shaft starting torque T1, torque loading frequency f, and loading cycle number n, and use them as input parameters for the drive device;

[0014] S2: Specimen Installation: Install the drive shaft to be tested onto the test bench. The sliding joint of the drive shaft is connected to the drive unit via a spline, and the spline parameters are consistent with those of the actual vehicle. The fixed joint of the drive shaft is connected to the hub via a spline, and the spline parameters are consistent with those of the actual vehicle. At the same time, the fixed joint of the drive shaft is fastened to the hub with nuts, and the fastening torque is consistent with the actual vehicle's fastening torque T2. The swing angle of the two universal joints at both ends of the drive shaft is 0°, and the center of the sliding joint should be within ±5mm of the theoretical design position.

[0015] S3: Test start: The drive unit outputs torque T3 and applies it to the drive shaft. The vibration acceleration signal a is detected and recorded by the vibration accelerometer sensor. The test stops after completing the number of cycles n.

[0016] S4: Data Processing and Analysis: After the experiment is completed, the data processing center outputs the correspondence between acceleration and time.

[0017] Optionally, in step S1, the starting torque T1 of the drive shaft is the torque on the drive shaft when the vehicle starts.

[0018] Optionally, in step S1, the torque loading frequency f is determined by the vehicle start-up response time t.

[0019] Optionally, in step S1, the number of loading cycles n is determined according to the number of starts specified in the road test.

[0020] This invention has the following advantages: By measuring the vibration acceleration 'a' of the wheel hub, it can determine whether there is abnormal noise during start-up and assess the degree of such noise. Furthermore, by measuring the wheel hub vibration acceleration 'a' with different configurations, it can evaluate the optimization effect of different configurations on abnormal start-up noise, thereby selecting the optimal configuration. In addition, since abnormal start-up noise may occur at high mileage, this invention can also simulate the high-mileage attenuation of the drive shaft by increasing the number of loading cycles 'n', achieving the measurement of wheel hub vibration acceleration 'a' and the assessment of abnormal start-up noise under different mileage conditions. Attached Figure Description

[0021] Figure 1 These are the implementation steps of the present invention;

[0022] Figure 2 This is a schematic diagram of the test apparatus of the present invention;

[0023] Figure 3 This is a schematic diagram of the input torque of the present invention;

[0024] Figure 4 This is a schematic diagram of acceleration-time in this invention;

[0025] In the diagram: 1. Drive unit, 2. Drive shaft, 3. Hub detection unit, 31. Hub, 32. Vibration acceleration sensor, 4. Data processing center. Detailed Implementation

[0026] The present invention will now be described in detail with reference to the accompanying drawings.

[0027] like Figure 2 As shown in this embodiment, a drive shaft starting noise test device includes a drive unit 1, a hub detection unit 3, and a data processing center 4. The drive unit 1 is a servo motor used to output torque T3 according to test requirements. The output shaft of the drive unit 1 is connected to the sliding joint 21 of the drive shaft under test. The hub detection unit 3 includes a hub 31 and a vibration accelerometer sensor 32. The hub 31 is used to simulate the assembly state of a real vehicle and is connected to the fixed joint 22 of the drive shaft 2. The vibration accelerometer sensor 32 is used to collect data and is mounted on the hub 31. The data processing center 4 is connected to the vibration accelerometer sensor 32. The data processing center 4 is used to store and process the detected data and output the correspondence between acceleration and time.

[0028] like Figure 1 As shown in this embodiment, a method for testing abnormal noise during drive shaft start-up uses the drive shaft start-up abnormal noise testing device described in this embodiment, and the method includes the following steps:

[0029] S1: Obtain test input parameters: Obtain the starting torque T1 of the drive shaft, the torque loading frequency f, and the number of loading cycles n, and use them as input parameters for drive device 1.

[0030] 1) Measure the torque T1 on the drive shaft when the vehicle starts, and use it as the input torque of drive device 1 (i.e., drive shaft starting torque T1); Example T1 = 1000 N.m.

[0031] 2) Torque loading frequency f: determined by the vehicle start-up response time t. Different vehicles have different response times. It is used as the input frequency of drive device 1. Example: t=500ms, f=2Hz.

[0032] The output torque T3 of drive unit 1 can be determined from the starting torque T1 of the drive shaft and the torque loading frequency f. Ultimately, drive unit 1 will output as shown in the figure. Figure 3The torque T3 is shown as ±1000 N·m with a frequency of 2 Hz and a periodic variation.

[0033] 3) The fastening torque T2 between the fixed section 22 of the drive shaft 2 and the hub 31 is determined according to the actual vehicle assembly technical requirements; for example, T2 = 200N.

[0034] 4) Number of loading cycles n: This number is determined based on the actual condition of the vehicle and can be determined according to the number of starts specified in the road test; for example, n=5000.

[0035] S2: Specimen installation, such as... Figure 2 As shown, drive shaft 2 is installed on the test bench. The sliding joint 21 of drive shaft 2 is connected to drive device 1 via a spline, and the spline parameters are consistent with those of the actual vehicle. The fixed joint 22 of drive shaft 2 is connected to wheel hub 31 via a spline, and the spline parameters are consistent with those of the actual vehicle. Simultaneously, the fixed joint 22 of drive shaft 2 and wheel hub 31 are tightened with nuts, and the tightening torque is consistent with the tightening torque T2 of the actual vehicle. The swing angle of the two universal joints at both ends of drive shaft 2 is 0°, and the center of sliding joint 21 should be within ±5mm of the theoretical design position.

[0036] S3: Test Start: Drive unit 1 will... Figure 3 The periodically varying output torque T3 is applied to the specimen, and the vibration acceleration signal a is monitored and recorded. The process stops after completing the required number of cycles n.

[0037] S4: Data Processing and Analysis: Output after the experiment is completed, as shown in the figure. Figure 4 The diagram shows the acceleration-time curve.

[0038] After the experiment is completed, analysis can be performed based on the output acceleration-time diagram, according to... Figure 4 For example, after three experiments, three curves were output, representing the vibration acceleration 'a' measured under schemes one, two, and three, respectively. From the curves, the following conclusions can be drawn:

[0039] 1. Option 1 ( Figure 4 In section A), the vibration acceleration a reached a maximum of 0.98g in the initial stage, which is much higher than the standard 0.5g. It can be determined that the scheme has a problem with abnormal noise at the start.

[0040] 2. Option Two ( Figure 4 In section B), during the second half of the test, when the number of cycles reached n=3120, the vibration accelerator a began to exceed 0.5g, and the vibration acceleration a also increased with the increase of the number of cycles. This indicates that the scheme will not have any abnormal noise problems at the start in the initial stage, but it will decrease with the increase of mileage, and abnormal noise problems will appear at the start in the later stage, which will not meet the design life requirements of the product.

[0041] 3. Option Three ( Figure 4In option C), after the number of cycles reaches n=5000, the vibration accelerator a still meets the requirement of less than 0.5g, indicating that option three will not have any abnormal noise during the product life cycle.

[0042] It should be noted that the above embodiments are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A test device for abnormal noise during drive shaft start-up, characterized in that: It includes a drive unit (1), a hub detection unit (3), and a data processing center (4); The drive device (1) is used to obtain the starting torque T1, torque loading frequency f and loading cycle number n of the drive shaft, and use them as input parameters of the drive device. It outputs torque T3 and applies it to the drive shaft (2). The output shaft of the drive device (1) is used to connect with the sliding joint (21) of the drive shaft under test. The hub detection unit (3) includes a hub (31) and a vibration accelerometer sensor (32). The hub (31) is used to simulate the assembly state of a real vehicle, and the hub (31) is used to connect with the fixed joint (22) of the drive shaft; The vibration accelerator sensor (32) is used to detect and record the vibration acceleration signal a, and the vibration accelerator sensor (32) is mounted on the hub (31); The data processing center (4) is connected to the vibration accelerometer sensor (32). The data processing center (4) is used to store and process the detected data and output the correspondence between acceleration and time. The drive shaft (2) to be tested is installed on the test bench. The sliding joint (21) of the drive shaft is connected to the drive device (1) by a spline, and the spline parameters are consistent with those of the actual vehicle. The fixed joint (22) of the drive shaft is connected to the wheel hub (31) by a spline, and the spline parameters are consistent with those of the actual vehicle. At the same time, the fixed joint (22) of the drive shaft is fastened to the wheel hub (31) by a nut, and the fastening torque is consistent with the fastening torque T2 of the actual vehicle.

2. The drive shaft starting noise test device according to claim 1, characterized in that: The driving device (1) is a servo motor.

3. A test method for abnormal noise during drive shaft start-up, characterized in that, The method of using the drive shaft start-up abnormal noise test device as described in claim 1 or 2 includes the following steps: S1: Obtain test input parameters: Obtain the starting torque T1 of the drive shaft, the torque loading frequency f and the number of loading cycles n, and use them as input parameters of the drive device (1); S2: Specimen Installation: The drive shaft (2) to be tested is installed on the test bench. The sliding joint (21) of the drive shaft is connected to the drive device (1) by a spline, and the spline parameters are consistent with those of the actual vehicle. The fixed joint (22) of the drive shaft is connected to the hub (31) by a spline, and the spline parameters are consistent with those of the actual vehicle. At the same time, the fixed joint (22) of the drive shaft is fastened to the hub (31) by a nut, and the fastening torque is consistent with the fastening torque T2 of the actual vehicle. The swing angle of the two universal joints at both ends of the drive shaft (2) is 0°, and the center of the sliding joint (21) should be within ±5mm of the theoretical design position. S3: Test start: The drive device (1) outputs torque T3 and applies it to the drive shaft (2). The vibration acceleration signal a is detected and recorded by the vibration accelerometer sensor (32). The test stops after completing the number of cycles n. S4: Data Processing and Analysis: After the experiment is completed, the data processing center outputs the correspondence between acceleration and time.

4. The test method for abnormal noise during drive shaft start-up according to claim 3, characterized in that: In step S1, the starting torque T1 of the drive shaft is the torque on the drive shaft when the vehicle starts.

5. The test method for abnormal noise during drive shaft start-up according to claim 3 or 4, characterized in that: In step S1, the torque loading frequency f is determined by the vehicle start-up response time t.

6. The test method for abnormal noise during drive shaft start-up according to claim 5, characterized in that: In step S1, the number of loading cycles n is determined according to the number of starts specified in the road test.

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