A method for testing abnormal noises in a differential

Abstract

The differential noise testing method provided in this application includes: detecting abnormal noise in a newly installed differential to determine if it is in a state of abnormal noise; adjusting the torque distribution coefficient of the differential after determining that it is in a state of abnormal noise; and detecting abnormal noise in the adjusted differential after completing the torque distribution coefficient adjustment to determine if it is in a state of abnormal noise. The differential noise testing method provided in this application, after determining that the differential has abnormal noise during cornering, can solve the NVH problem caused by the abnormal noise by adjusting the torque distribution coefficient. The differential after noise treatment can be shipped out, thereby achieving risk identification before the differential leaves the factory for use, improving the product quality of the differential, greatly saving the later maintenance costs of the differential, and improving the user experience.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a method for testing abnormal noises in a differential. Background Technology

[0002] As a key component of vehicle steering, the differential achieves differential turning of the left and right wheels through internal friction torque. However, if the friction torque is too large, it will cause stick-slip noise, leading to NVH (Noise, Vibration, Harshness) problems for the entire vehicle and affecting the user experience.

[0003] The relevant technologies for identifying abnormal noises during cornering generally involve testing and identifying the entire vehicle after it has been taken off the production line. Evaluation is conducted by evaluators. If abnormal noises during cornering are found in the differential during the vehicle evaluation, the only solution to the NVH problem is to replace the entire differential assembly, which is extremely costly. Summary of the Invention

[0004] In view of this, the embodiments of this application aim to provide a method for testing abnormal noise of a differential, which can solve the NVH problem caused by abnormal noise of the differential and save the later maintenance cost of the differential.

[0005] To achieve the above objectives, embodiments of this application provide a method for testing abnormal noise in a differential, comprising:

[0006] Perform an abnormal noise test on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state.

[0007] If the differential is found to be in an abnormal noise state after initial installation, the torque distribution coefficient of the differential is adjusted.

[0008] After adjusting the torque distribution coefficient of the differential, an abnormal noise detection is performed on the adjusted differential to determine whether the adjusted differential is in an abnormal noise state.

[0009] In some embodiments, the step of adjusting the torque distribution coefficient of the differential specifically includes:

[0010] Obtain the adjustment torque distribution coefficient of the differential, wherein the adjustment torque distribution coefficient is less than the theoretical torque distribution coefficient;

[0011] According to the torque distribution adjustment coefficient, the friction pair of the differential is surface treated or the size of the friction pair of the differential is adjusted.

[0012] In some embodiments, the abnormal noise testing method includes:

[0013] If the differential is found to be making abnormal noise after adjustment, the torque distribution coefficient of the differential is adjusted again.

[0014] In some embodiments, the abnormal noise detection includes:

[0015] The differential is subjected to sound intensity assessment;

[0016] Vibration assessment of the differential;

[0017] The torque distribution coefficient of the differential is determined.

[0018] In some embodiments, the step of judging the sound intensity of the differential specifically includes:

[0019] Obtain the preset sound intensity value and the actual sound intensity value of the differential;

[0020] Compare the actual sound intensity value with the preset sound intensity value;

[0021] If the actual sound intensity value is greater than the preset sound intensity value, then the differential is in an abnormal noise state.

[0022] In some embodiments, the step of determining vibration in the differential specifically includes:

[0023] Obtain the preset vibration limit and actual vibration value of the differential;

[0024] Compare the actual vibration value with the preset vibration limit value;

[0025] If the actual vibration value is determined to be greater than the preset vibration limit, then the differential is in an abnormal noise state.

[0026] In some embodiments, the step of determining the torque distribution coefficient of the differential specifically includes:

[0027] Obtain the theoretical torque distribution coefficient and the actual torque distribution coefficient of the differential;

[0028] If the difference between the actual torque distribution coefficient and the theoretical torque distribution coefficient is greater than a preset difference range, then the differential is in an abnormal noise state.

[0029] In some embodiments, prior to the step of detecting abnormal noise in the differential, the abnormal noise processing method further includes:

[0030] The actual torque distribution coefficient of the differential is detected under a preset operating condition, which is the extreme cornering condition.

[0031] In some embodiments, detecting the actual torque distribution coefficient of the differential under preset operating conditions specifically includes:

[0032] Under the preset operating conditions, the torque distribution coefficient of the differential is tested for a first preset number of test cycles to obtain multiple test torque distribution coefficients corresponding to the first preset number of test cycles.

[0033] The test torque distribution coefficient of the last test cycle of the first preset test cycle is taken as the actual torque distribution coefficient.

[0034] In some embodiments, before the step of detecting abnormal noise in the initially installed differential, the abnormal noise detection method further includes:

[0035] Input the friction torque parameters of the differential and calculate the theoretical torque distribution coefficient of the gearbox.

[0036] The differential noise testing method provided in this application embodiment, after determining that there is abnormal noise in the differential during cornering, can solve the NVH problem caused by the abnormal noise by adjusting the torque distribution coefficient of the differential. The differential after the abnormal noise is treated can be shipped off the production line, thereby realizing risk identification before the differential leaves the factory for use, improving the product quality of the differential, greatly saving the later maintenance cost of the differential, and helping to improve the user experience. Attached Figure Description

[0037] Figure 1 This is a flowchart illustrating a method for testing abnormal noise from a differential provided in one embodiment of this application.

[0038] Figure 2 This is a flowchart illustrating a method for testing abnormal noise from a differential provided in another embodiment of this application. Detailed Implementation

[0039] It should be noted that, unless otherwise specified, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed descriptions in the specific implementation should be understood as explanations of the purpose of this application and should not be regarded as undue limitations on this application.

[0040] In related technologies, the differential is a key component for vehicle steering. The internal friction torque of the differential is an inherent characteristic, and differential turning of the left and right wheels is achieved through this internal friction torque during steering. Simultaneously, friction torque is a key cause of abnormal noises during steering, and the main sources of friction torque are the friction torque at the half-shaft gear shims, the friction torque between the planetary gears and the half-shaft gears, the friction torque at the planetary gear shims, and the friction torque at the planetary shaft.

[0041] The specific friction torque parameters include: the coefficient of friction between the axle shim and the differential housing and the axle gear; the axial force of the axle gear; the outer diameter of the axle shim; the inner diameter of the axle shim; the coefficient of friction between the planetary shim and the differential housing and the planetary gear; the axial force of the planetary gear; the outer diameter of the planetary shim; the inner diameter of the planetary shim; the coefficient of friction between the planetary shaft and the planetary gear bore; the normal force of the planetary shaft; and the planetary shaft diameter, etc.

[0042] The friction torque parameters can be used to calculate the friction torque at the half-shaft gear shim, the friction torque at the planetary gear shim, the friction torque between gears, and the friction torque at the planetary shaft. The actual friction torque can be calculated based on the four friction torques, and the theoretical torque distribution coefficient can be further derived from the friction torque.

[0043] It should be noted that the friction torque parameter can be obtained through bench steady-state testing. The specific control variables and testing procedures involved in bench steady-state testing of the friction torque parameter are widely and maturely applied in related technologies, and will not be elaborated upon here.

[0044] One embodiment of this application provides a method for testing abnormal noises in a differential, including:

[0045] S1: Perform abnormal noise detection on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state.

[0046] S2: Determine that the initially installed differential is in an abnormal noise state, and adjust the torque distribution coefficient of the differential.

[0047] S3: After adjusting the torque distribution coefficient of the differential, perform abnormal noise detection on the adjusted differential to determine whether the adjusted differential is in an abnormal noise state.

[0048] The specific implementation method of the above steps of the differential noise test method is described below.

[0049] S1: Perform an abnormal noise test on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state.

[0050] Understandably, a differential making abnormal noise means that the differential will produce stick-slip noise during vehicle slippage or cornering, thus causing NVH (Noise, Vibration, and Harshness) problems for the entire vehicle. Therefore, abnormal noise detection involves simulating the operating conditions of a vehicle slipping or cornering. By detecting abnormal noise, it is possible to determine whether the differential will produce stick-slip noise, thereby determining whether the differential is in an abnormal noise state or a normal state.

[0051] S2: Determine that the initially installed differential is in an abnormal noise state, and adjust the torque distribution coefficient of the differential.

[0052] By detecting abnormal noises, it can be determined that the newly installed differential is in an abnormal noise state, which means that the internal friction torque of the newly installed differential is too large. By adjusting the torque distribution coefficient of the differential, mainly by reducing the preset torque distribution coefficient required by the initial design of the differential, the friction torque of the differential is reduced, thereby reducing the probability of abnormal noise from the differential.

[0053] S3: After adjusting the torque distribution coefficient of the differential, perform abnormal noise detection on the adjusted differential to determine whether the adjusted differential is in an abnormal noise state.

[0054] If the adjusted differential is determined to be in a normal state, it means that by adjusting the torque distribution coefficient of the differential, the NVH problem caused by abnormal noise in the differential has been solved. The adjusted differential can be shipped off the production line, thereby realizing risk identification before the differential leaves the factory for use, improving the product quality of the differential, greatly saving later maintenance costs, and helping to improve the user experience.

[0055] If the adjusted differential is found to be in an abnormal noise state, the torque distribution coefficient of the differential needs to be readjusted, and subsequent abnormal noise treatment methods need to be implemented to ensure that the abnormal noise treatment method of this application can solve the NVH problem caused by the abnormal noise of the differential. That is, if the adjusted differential is found to be in an abnormal noise state, the torque distribution coefficient of the differential needs to be readjusted again until the abnormal noise test is passed.

[0056] In some embodiments, if the adjusted differential is found to be in an abnormal noise state, the torque distribution coefficient of the differential is adjusted again.

[0057] Understandably, if the adjusted differential still produces abnormal noise, it indicates that the torque distribution coefficient of the differential is still set too high, resulting in excessive friction torque and causing the noise. Therefore, it is necessary to readjust the torque distribution coefficient of the differential to reduce the friction torque and resolve the noise issue.

[0058] In some embodiments, the step of adjusting the torque distribution coefficient of the differential specifically includes:

[0059] Obtain the adjustment torque distribution coefficient of the differential, where the adjustment torque distribution coefficient is less than the theoretical torque distribution coefficient;

[0060] Based on the torque distribution coefficient, the friction pairs of the differential are surface-treated or their dimensions are adjusted.

[0061] It's understandable that when a differential reaches its theoretical torque distribution coefficient during initial assembly, its performance is optimal and there are no abnormal noises. However, during the manufacturing and assembly process, factors such as assembly precision and the quality of structural components can cause discrepancies between the actual and theoretical torque distribution coefficients of the assembled differential. In other words, the actual torque distribution coefficient of the assembled differential may be greater than the theoretical torque distribution coefficient during initial design, resulting in excessive friction torque and abnormal noise.

[0062] Therefore, adjusting the torque distribution coefficient of a differential mainly involves redesigning the differential by obtaining a new torque distribution coefficient, which is called the adjustment torque distribution coefficient. The adjustment torque distribution coefficient should be less than the theoretical torque distribution coefficient to improve the tolerance of differential production and assembly. This reduces the probability that the adjusted differential's torque distribution coefficient will exceed the theoretical torque distribution coefficient, thereby reducing the likelihood of excessive friction torque in the differential causing abnormal noise.

[0063] Adjusting the torque distribution coefficient of a differential can be achieved by surface treatment of the differential's friction pairs. This primarily involves treating the surfaces of the structural components within the differential, such as phosphating, nickel plating, QPQ (Quench-Polish-Quench), and other plating processes. This makes the surfaces of the structural components within the differential smoother, reducing the friction coefficient of the friction surfaces and consequently reducing the friction torque between the components, thus lowering the likelihood of abnormal noises from the differential.

[0064] Adjusting the torque distribution coefficient of the differential can be achieved by adjusting the dimensions of the friction pairs within the differential, primarily by adjusting the major and minor diameters of the structural components inside the differential. This improves the meshing relationship between the structural components, reduces the frictional torque between them, and thus lowers the likelihood of abnormal noises from the differential.

[0065] It should be noted that the adjustment torque distribution coefficient should be less than the theoretical torque distribution coefficient. Specifically, the difference between the adjustment torque distribution coefficient and the theoretical torque distribution coefficient should be within a preset difference range, which is 10% to 20% of the theoretical torque distribution coefficient, such as 10%, 12%, 14%, 16%, 18%, and 20%.

[0066] In some embodiments, abnormal noise detection includes at least two of the following steps:

[0067] S11: Determine the sound intensity of the differential;

[0068] S12: Vibration detection of the differential;

[0069] S13: Determine the torque distribution coefficient of the differential.

[0070] The specific implementation methods of steps S11 to S13 of the abnormal noise detection are described below.

[0071] S11: Determine the sound intensity of the differential.

[0072] It is understandable that the abnormal noise emitted by the differential has a certain sound intensity, which can be directly detected by relevant instruments for measuring sound intensity, or can be directly recognized by the human ear when the sound intensity is high enough.

[0073] S12: Vibration detection of the differential.

[0074] It is understandable that a pre-installed differential has a certain preset vibration limit. When an abnormal noise occurs in the differential, it will be accompanied by a vibration exceeding the limit, meaning that the actual vibration value of the differential when the abnormal noise occurs is greater than the preset vibration limit. Therefore, vibration assessment of the differential can be used to determine whether an abnormal noise has occurred.

[0075] S13: Determine the torque distribution coefficient of the differential.

[0076] It is understandable that the torque distribution coefficient of the differential is judged, that is, the actual torque distribution coefficient of the differential after initial installation or adjustment is compared with the theoretical torque distribution coefficient of the differential design. If the actual torque distribution coefficient is greater than the theoretical torque distribution coefficient and the error is large, it will cause excessive friction torque between structural components, thus causing abnormal noise.

[0077] Of the three steps in abnormal noise detection, judging the sound intensity is the most intuitive and convenient method. Therefore, in the three judgments involved in abnormal noise detection, judging the sound intensity can be performed first to save time and costs.

[0078] The specific order of vibration judgment and torque distribution coefficient judgment is not limited. For example, in this application, after the sound intensity judgment, the vibration judgment is performed first and then the torque distribution coefficient judgment is performed.

[0079] Specifically, the differential undergoes an acoustic intensity assessment. If the differential is found to be making abnormal noise, the process proceeds directly to the subsequent processing steps after noise detection. If the differential is found to be in a normal state, a vibration assessment is performed. If the differential is found to be making abnormal noise, the process proceeds directly to the subsequent processing steps after noise detection. If the differential is found to be in a normal state, the torque distribution coefficient is assessed. If the differential is found to be making abnormal noise, the process proceeds directly to the subsequent processing steps after noise detection. If the differential is found to be in a normal state, the differential can be shipped out.

[0080] In some embodiments, determining that the differential is in a normal state requires the differential to simultaneously meet the criteria of sound intensity judgment, vibration judgment, and torque distribution coefficient judgment. If the judgment result of any one of the three is that the differential is in an abnormal noise state, then the subsequent processing steps after abnormal noise detection are directly entered.

[0081] In some embodiments, determining that the differential is in a normal state requires the differential to simultaneously meet at least two of the following criteria: sound intensity judgment, vibration judgment, and torque distribution coefficient judgment. If the result of any one of the three judgments is that the differential is in an abnormal noise state, then the subsequent processing steps after abnormal noise detection are directly entered.

[0082] In some embodiments, prior to the initial noise detection step of the differential, the noise detection method further includes:

[0083] Input the friction torque parameters of the differential and calculate the theoretical torque distribution coefficient of the gearbox.

[0084] In some embodiments, step S11 is the step of judging the sound intensity of the differential, specifically including:

[0085] Obtain the preset and actual sound intensity values ​​of the differential;

[0086] Compare the actual sound intensity value with the preset sound intensity value;

[0087] If the actual sound intensity value is greater than the preset sound intensity value, the differential is in an abnormal noise state.

[0088] Under normal circumstances, the noise emitted by the differential exceeds the preset noise level and will be quite loud. Therefore, by comparing the actual noise level with the preset noise level, it is possible to determine whether the differential is in an abnormal noise state or in a normal state, and to perform subsequent processing steps according to the state of the differential.

[0089] The actual sound intensity value can be detected by instruments that measure sound intensity. The specific type of instrument used to measure sound intensity is not limited, such as a decibel meter.

[0090] The specific value of the preset sound intensity is not limited. For example, the preset sound intensity value can be in the range of 70 dB to 80 dB, such as 70 dB, 72 dB, 75 dB, 77 dB and 80 dB.

[0091] It should be noted that the preset acoustic intensity value was obtained through bench steady-state testing. The specific control variables and test procedures involved in the bench steady-state testing of the preset acoustic intensity value are widely and maturely applied in related technologies, and will not be elaborated here.

[0092] In some embodiments, step S12 is the step of determining the vibration of the differential, specifically including:

[0093] Obtain the preset vibration limit and actual vibration value of the differential;

[0094] Compare the actual vibration value with the preset vibration limit;

[0095] If the actual vibration value is greater than the preset vibration limit, the differential is in an abnormal noise state.

[0096] Under normal circumstances, if the actual vibration value of the differential exceeds the preset vibration limit, abnormal noise will occur. Therefore, by comparing the actual vibration value with the preset vibration limit, it is possible to determine whether the differential is in an abnormal noise state or in a normal state, and to perform subsequent processing steps according to the state of the differential.

[0097] The actual vibration value of the differential can be detected by instruments that measure differential vibration. The specific type of instrument used to measure differential vibration is not limited, such as vibration sensors.

[0098] It should be noted that the preset vibration limit is obtained through bench steady-state testing. The specific control variables and test procedures involved in the bench steady-state testing of the preset vibration limit are widely and maturely applied in related technologies, and will not be elaborated here.

[0099] In some embodiments, step S13 is the step of determining the torque distribution coefficient of the differential, specifically including:

[0100] Obtain the theoretical torque distribution coefficient and the actual torque distribution coefficient of the differential;

[0101] If the difference between the actual torque distribution coefficient and the theoretical torque distribution coefficient is greater than the preset difference range, the differential will be in an abnormal noise state.

[0102] Generally, if the actual torque distribution coefficient of the differential exceeds the theoretical torque distribution coefficient, it will cause excessive friction torque between structural components, resulting in abnormal noise. Therefore, by determining the difference between the actual torque distribution coefficient and the theoretical torque distribution coefficient, it is possible to determine whether the differential is in an abnormal noise state or a normal state, and to perform subsequent processing steps according to the state of the differential.

[0103] The specific value of the preset difference range is not limited. For example, the preset difference range is 10% of the theoretical torque distribution coefficient. That is, when the difference between the actual torque distribution coefficient and the theoretical torque distribution coefficient is greater than 10% of the theoretical torque distribution coefficient, the differential is in an abnormal noise state.

[0104] It should be noted that the preset difference range is obtained through bench steady-state testing. The specific control variables and test procedures involved in the bench steady-state testing of the preset difference range are widely and maturely applied in related technologies, and will not be elaborated here.

[0105] In some embodiments, prior to detecting abnormal noises in the differential, the following steps are included:

[0106] The actual torque distribution coefficient of the differential is detected under preset operating conditions.

[0107] The preset operating condition is the extreme cornering condition, which specifically refers to the extreme cornering condition simulated by the test bench at a vehicle speed of 15-20km / h, with the accelerator pedal pressed hard, the accelerator pedal relaxed, and the steering wheel turned left and right alternately to the full lock. At the same time, in this condition, the torque of the differential is controlled within the preset range of the theoretical torque.

[0108] Under preset operating conditions, the torque of the left half-shaft and the torque of the right half-shaft of the differential can reach the maximum difference. By measuring the torque of the differential, the torque of the left half-shaft and the torque of the right half-shaft of the differential can be obtained, and the actual torque distribution coefficient of the test can be obtained by further calculating based on the two.

[0109] The specific type of instrument used to measure differential torque is not limited, such as a torque sensor.

[0110] The actual torque distribution coefficient can be obtained through multiple test torque distribution coefficients. Specifically, this means testing the differential under preset operating conditions for a first preset number of test cycles. The specific value of the first preset number of test cycles is not limited, such as 4, 5, 6, 7, etc. For example, the first preset number of test cycles is 5. In this way, multiple test torque distribution coefficients can be obtained through multiple tests, thereby reducing the error of the test torque distribution coefficient. The number of test torque distribution coefficients is 5.

[0111] The actual torque distribution coefficient is obtained by testing multiple torque distribution coefficients. The coefficient obtained from the last torque distribution coefficient test performed on the differential under preset operating conditions can be selected as the actual torque distribution coefficient. It is understandable that when the differential undergoes torque distribution coefficient testing under preset operating conditions, the internal structural components of the differential will undergo a break-in process. After multiple torque distribution coefficient tests, the differential tends to stabilize under the preset operating conditions. Therefore, using the last torque distribution coefficient obtained from the preset operating conditions test as the actual torque distribution coefficient is more stable.

[0112] It should be noted that in this embodiment, both the initially installed differential and the differential after adjusting the torque distribution coefficient need to be tested for abnormal noise. Since the adjusted differential will cause a change in the actual torque distribution coefficient, and the actual torque distribution coefficient of the initially installed differential is also unknown, before testing the abnormal noise of both the initially installed differential and the adjusted differential, it is necessary to test the actual torque distribution coefficient of the differential under preset operating conditions to obtain the actual torque distribution coefficients corresponding to both, so as to use the torque distribution coefficient judgment included in the abnormal noise detection.

[0113] The specific value of the preset range of theoretical torque is not limited. For example, the preset range of theoretical torque is 15% to 20% of the theoretical torque. Controlling the torque of the differential to be within 15% to 20% of the theoretical torque can prevent damage to the differential.

[0114] It should be noted that the theoretical torque is obtained through bench steady-state testing. The specific control variables and testing procedures involved in the bench steady-state testing for the preset theoretical torque are widely and maturely applied in related technologies and will not be elaborated upon here.

[0115] In some embodiments, the differential is subjected to abnormal noise detection under preset operating conditions and a second preset number of test cycles.

[0116] It should be noted that the abnormal noise detection of the initially installed differential, the abnormal noise detection of the differential after break-in, and the abnormal noise detection of the adjusted differential in the aforementioned embodiments are all abnormal noise detection of the differential. That is, the abnormal noise detection in all three cases is carried out under preset operating conditions and a second preset number of test cycles.

[0117] The preset operating condition is the extreme cornering condition, which mainly refers to the extreme cornering condition simulated on a test bench at a vehicle speed of 15-20 km / h, with sudden acceleration, relaxed acceleration, and alternating left and right full steering wheel turns. Simultaneously, under this condition, the torque of the differential is controlled within the preset range of its theoretical torque. Under this preset condition, the probability of abnormal noise from the differential is significantly increased.

[0118] The specific number of the second preset test cycles is not limited. For example, under normal circumstances, the second preset test cycle is 1 time, that is, the differential is tested for abnormal noise once under preset operating conditions. This completes the three judgments included in the abnormal noise detection and determines whether the differential is in an abnormal noise state or in a normal state.

[0119] See below. Figure 2 This application provides a detailed description of the methods for handling abnormal noise from differentials in some embodiments.

[0120] S10: Input the friction torque parameters of the differential and calculate the theoretical torque distribution coefficient of the differential;

[0121] S20: Test the torque distribution coefficient of the newly installed differential;

[0122] S30: Perform an audio intensity test on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state. If yes, proceed to step S60; otherwise, proceed to step S40.

[0123] S40: Perform vibration judgment on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state. If yes, proceed to step S60; otherwise, proceed to step S50.

[0124] S50: Determine the torque distribution coefficient of the newly installed differential and determine whether the newly installed differential is in an abnormal noise state. If yes, proceed to step S60; otherwise, end the abnormal noise handling method.

[0125] S60: Adjusts the torque distribution coefficient of the differential;

[0126] S70: Judge the sound intensity of the adjusted differential. If the adjusted differential is in an abnormal noise state, proceed to step S60. If the adjusted differential is in a normal state, proceed to step S80.

[0127] S80: Perform vibration judgment on the adjusted differential. If the adjusted differential is found to be in an abnormal noise state, proceed to step S60. If the adjusted differential is found to be in a normal state, proceed to step S90.

[0128] S90: Determine the torque distribution coefficient of the adjusted differential. If the adjusted differential is found to be in an abnormal noise state, proceed to step S60. If the adjusted differential is found to be in a normal state, end the abnormal noise handling method.

[0129] The various embodiments / implementations provided in this application can be combined with each other without creating contradictions.

[0130] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for testing abnormal noise in a differential, characterized in that, include: Perform an abnormal noise test on the newly installed differential to determine whether the newly installed differential is in an abnormal noise state. If the differential is found to be in an abnormal noise state after initial installation, the torque distribution coefficient of the differential is adjusted. After the torque distribution coefficient of the differential is adjusted, the differential is subjected to abnormal noise detection to determine whether the differential is in an abnormal noise state. If the differential is found to be making abnormal noise after adjustment, the torque distribution coefficient of the differential is adjusted again. The step of adjusting the torque distribution coefficient of the differential specifically includes: Obtain the adjustment torque distribution coefficient of the differential, wherein the adjustment torque distribution coefficient is less than the theoretical torque distribution coefficient; According to the torque distribution adjustment coefficient, the friction pair of the differential is surface treated or the size of the friction pair of the differential is adjusted.

2. The abnormal noise testing method according to claim 1, characterized in that, The abnormal noise detection includes: The differential is subjected to sound intensity assessment; Vibration assessment of the differential; The torque distribution coefficient of the differential is determined.

3. The abnormal noise testing method according to claim 2, characterized in that, The steps for judging the sound intensity of the differential specifically include: Obtain the preset sound intensity value and the actual sound intensity value of the differential; Compare the actual sound intensity value with the preset sound intensity value; If the actual sound intensity value is greater than the preset sound intensity value, then the differential is in an abnormal noise state.

4. The abnormal noise testing method according to claim 2, characterized in that, The steps for determining the vibration of the differential specifically include: Obtain the preset vibration limit and actual vibration value of the differential; Compare the actual vibration value with the preset vibration limit value; If the actual vibration value is determined to be greater than the preset vibration limit, then the differential is in an abnormal noise state.

5. The abnormal noise testing method according to claim 2, characterized in that, The steps for determining the torque distribution coefficient of the differential specifically include: Obtain the theoretical torque distribution coefficient and the actual torque distribution coefficient of the differential; If the difference between the actual torque distribution coefficient and the theoretical torque distribution coefficient is greater than a preset difference range, then the differential is in an abnormal noise state.

6. The abnormal noise testing method according to claim 1, characterized in that, Before the step of detecting abnormal noise in the differential, the abnormal noise handling method further includes: The actual torque distribution coefficient of the differential is detected under a preset operating condition, which is the extreme cornering condition.

7. The method for handling abnormal noise according to claim 6, characterized in that, Detecting the actual torque distribution coefficient of the differential under preset operating conditions specifically includes: Under the preset operating conditions, the torque distribution coefficient of the differential is tested for a first preset number of test cycles to obtain multiple test torque distribution coefficients corresponding to the first preset number of test cycles. The test torque distribution coefficient of the last test cycle of the first preset test cycle is taken as the actual torque distribution coefficient.

8. The abnormal noise testing method according to claim 1, characterized in that, Before performing abnormal noise detection on the initially installed differential, the abnormal noise detection method further includes: Input the friction torque parameters of the differential and calculate the theoretical torque distribution coefficient of the gearbox.

Images