Seat belt retractor noise testing device and method

Abstract

The present application is suitable for the field of testing equipment, and particularly relates to a safety belt retractor abnormal sound testing device and method. The testing device comprises a support rack, at least one elastic structural member, a vibration table and a bushing. The elastic structural member is arranged between the support rack and the vibration platform to reduce the influence of external vibration other than the excitation source on the vibration platform. One end of the vibration table is fixed on the preset part of the elastic structural member through the bushing, and the other end of the vibration table is fixed on the remaining part of the elastic structural member. Meanwhile, the vibration generated by the rotation of the safety belt retractor around the X axis and the Z direction excitation are simulated, and the rationality and accuracy of the safety belt retractor abnormal sound testing are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of testing equipment, in particular to a seat belt retractor abnormal sound testing device and method. BACKGROUND

[0002] Based on the structural characteristics of the seat belt retractor, the sensitive components must have a movable ball to meet the safety function of the product. The movable ball is the main noise source of the seat belt retractor abnormal sound. When the seat belt retractor is excited, the movable ball will inevitably produce noise in its structure. When the generated noise is large, it will directly reduce the comfort of the vehicle occupants. Therefore, it is necessary to test the seat belt retractor abnormal sound.

[0003] In the traditional method, whether the seat belt retractor has abnormal sound is tested on a vibration bench in an anechoic chamber environment. The seat belt retractor noise cannot exceed a certain decibel under certain excitation as a reference. Since the seat belt retractor is installed on both sides of the vehicle, the main excitation is the vibration generated by the Z-direction excitation and the rotation around the X-axis. The traditional vibration table is a single-degree-of-freedom excitation in the Z-direction, which cannot well simulate the vibration under the whole vehicle state, resulting in low accuracy of the seat belt retractor abnormal sound test.

[0004] In addition, the vibration bench for testing the seat belt retractor is in an anechoic chamber environment, and the weight of high-frequency components is low, which cannot affect the size of the overall sound pressure level. The noise range of the movable ball is in the high-frequency band, so the traditional method cannot identify the true noise level of the movable ball in its mechanism, further reducing the accuracy of the seat belt retractor abnormal sound test.

[0005] Therefore, how to improve the accuracy of the seat belt retractor abnormal sound test has become a problem to be solved. SUMMARY

[0006] Therefore, the embodiments of the present application provide a seat belt retractor abnormal sound testing device and method to solve the problem of low accuracy of the seat belt retractor abnormal sound test.

[0007] In a first aspect, the embodiments of the present application provide a seat belt retractor abnormal sound testing device, which comprises a support bench, at least one elastic structural member, a vibration table surface and a bushing.

[0008] Each of the elastic structural members is fixed on the corresponding support part of the support bench, and the bushing is fixed on the elastic structural member of the preset part.

[0009] One end of the vibration table surface is fixed on the elastic structural member of the preset part through the bushing, and the other end of the vibration table surface is fixed on the elastic structural member of the remaining part.

[0010] The vibration table is used for vertical vibration of the excitation of the excitation source when the seat belt retractor is tested for abnormal sound, and axial rotation around the bushing to simulate horizontal vibration.

[0011] Optionally, the bushing comprises a central shaft and a bushing shell;

[0012] The central shaft is arranged inside the bushing shell, and the central shaft connects the bushing shell through rubber;

[0013] The bushing shell rigidly connects the elastic structural member at the preset part, and the end of the central shaft rigidly connects the vibration table.

[0014] Optionally, the central shaft is connected to the elastic structural member of the remaining part through a connecting rod at both ends.

[0015] Optionally, the elastic structural member is an air spring.

[0016] Optionally, the support rack comprises a rack mounting surface and a plurality of support portions, and each support portion is fixed on the rack mounting surface.

[0017] Optionally, the test device further comprises an exciter, and the exciter is fixed on the corresponding support portion of the support rack.

[0018] Optionally, the test device further comprises a sound collecting device, and the sound collecting device is fixed on the rack mounting surface.

[0019] In a second aspect, the embodiments of the present application provide a seat belt retractor abnormal sound test method, which uses the test device of the first aspect to test the seat belt retractor, and the test method comprises:

[0020] Inputting an excitation signal to make the seat belt retractor produce vertical vibration and horizontal vibration, and collecting a noise signal of the seat belt retractor;

[0021] Signal processing the noise signal to obtain a high-frequency noise signal;

[0022] Calculating a noise sound pressure value according to the high-frequency noise signal, and calculating a noise decibel according to the noise sound pressure value;

[0023] Determining an abnormal sound test result of the seat belt retractor according to the noise decibel.

[0024] Compared with the prior art, the embodiment of the present application has the beneficial effects that: the embodiment of the present application sets the elastic structure between the support rack and the vibration platform to reduce the influence of external vibration other than the excitation source on the vibration platform, and fixes one end of the vibration platform to the elastic structure of the preset part through the bushing and fixes the other end of the vibration platform to the elastic structure of the remaining part, so that the vibration generated by the rotation of the seat belt retractor around the X axis and the Z direction excitation can be simulated at the same time, the vibration of the seat belt retractor under the whole vehicle state is simulated more truly, and the rationality and accuracy of the abnormal sound test of the seat belt retractor are improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0026] Figure 1 is a schematic view of a seat belt retractor abnormal sound test device in the embodiment one of the present application;

[0027] Figure 2 is a schematic view of a seat belt retractor abnormal sound test device in the embodiment one of the present application;

[0028] Figure 3 is a perspective view of a seat belt retractor abnormal sound test device in the embodiment two of the present application;

[0029] Figure 4 is a left view of a seat belt retractor abnormal sound test device in the embodiment two of the present application;

[0030] Figure 5 is a front view of a seat belt retractor abnormal sound test device in the embodiment two of the present application;

[0031] Figure 6 is a schematic view of an application environment of a seat belt retractor abnormal sound test method provided in the embodiment three of the present application;

[0032] Figure 7 is a flowchart of a seat belt retractor abnormal sound test method provided in the embodiment three of the present application;

[0033] In the figure, 1 is a support rack, 2 is an elastic structure, 3 is a vibration platform, 4 is a bushing, 5 is an exciter, 6 is a radio device, 11 is a rack mounting surface, 12 is a support part, 41 is a center shaft, and 42 is a bushing shell. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the present application will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0035] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified.

[0036] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] In order to illustrate the technical solutions of the present application, the following specific embodiments are described.

[0038] Referring to Figure 1 The test device provided by the embodiment one of the present application is a safety belt retractor abnormal sound test device, which comprises a support rack 1, two elastic structural members 2, a vibration table surface 3 and a bushing 4.

[0039] The two elastic structural members 2 are respectively fixed on the corresponding support portions of the support rack 1, the bushing 4 is fixed on the elastic structural member 2 of the preset portion, one end of the vibration table surface 3 is fixed on the elastic structural member 2 of the preset portion through the bushing 4, the other end of the vibration table surface 3 is fixed on the elastic structural member 2 of the remaining portion, the vibration table surface 3 is used for vertical vibration under the excitation of the excitation source when the safety belt retractor is tested for abnormal sound, and axial rotation around the bushing 4 to simulate horizontal vibration.

[0040] Specifically, the elastic structure 2 is arranged between the support frame 1 and the vibration table 3, and is used to reduce the influence of external vibrations other than the excitation source on the vibration table 3 during the simulation of vibration, so as to improve the accuracy of the abnormal sound test of the seat belt retractor. One end of the vibration table 3 is fixed on the elastic structure 2 of the preset part through the bushing 4. When the vibration table 3 is excited by the excitation source, the one end of the vibration table 3 rotates axially around the bushing 4, simulating the vibration generated by the rotation of the seat belt retractor around the X axis. The other end of the vibration table 3 is fixed on the elastic structure 2 of the remaining part. When the vibration table 3 is excited by the excitation source, the other end of the vibration table 3 performs vertical vibration, simulating the Z excitation of the seat belt retractor. Therefore, the vibration table 3 can simultaneously simulate the vibration generated by the rotation of the seat belt retractor around the X axis and the Z excitation, that is, the main vibration of the seat belt retractor in the whole vehicle state, so as to improve the rationality and accuracy of the abnormal sound test of the seat belt retractor.

[0041] In an example, the elastic structure 2 is an air spring. Since the vibration isolation performance of the air spring is better than that of the rigid spring, the influence of external vibrations other than the excitation source on the vibration platform can be more effectively reduced. At the same time, the lateral stiffness of the air spring is higher than that of the rigid spring, so that the horizontal translation of the vibration platform can be better controlled, thereby realizing the rotation of the vibration platform around the bushing 4, simulating the vibration generated by the rotation of the seat belt retractor around the X axis, and effectively improving the rationality and accuracy of the abnormal sound test of the seat belt retractor.

[0042] In an example, the number of elastic structures 2 can be 2, 3, 4 or 5, etc. Each elastic structure 2 is arranged on the corresponding support part. The number of bushings 4 can be 1, 2, 3 or 4, etc., and each bushing 4 is fixed on the elastic structure 2 of the preset part.

[0043] In an example, the test device is arranged in a soundproof environment to avoid the interference of other noises in the environment on the abnormal sound test of the seat belt retractor.

[0044] The schematic view of the bushing 4 is shown in Figure 2 The bushing 4 includes a central shaft 41 and a bushing shell 42.

[0045] The central shaft 41 is arranged inside the bushing shell 42, and the central shaft 41 is connected to the bushing shell 42 through rubber. Since the rubber has a certain deformation amount, the central shaft 41 and the bushing shell 42 can move relative to the axis. Specifically, when the central shaft 41 is fixed, the bushing shell 42 can move around the axis, and when the bushing shell 42 is fixed, the central shaft 41 can move around the axis.

[0046] Meanwhile, the sleeve shell 42 is rigidly connected to the elastic structural member 2 of the preset part, and the end of the central shaft 41 is rigidly connected to the vibration platform 3, so that when the central shaft 41 and the sleeve shell 42 move relatively around the axis, the vibration platform 3 can rotate around the sleeve 4 and transmit the generated vibration to the vibration platform 3, thereby simulating the vibration generated by the rotation of the seat belt retractor around the X axis. Meanwhile, the central shaft 41 is connected to the elastic structural member 2 of the remaining part through the connecting rod, so as to increase the rigidity of the fixed connection, improve the stability of the testing device, and reduce the influence of the deformation of the device structure on the test results.

[0047] It should be noted that, since the vibration platform 3 moves around the axis with a small amplitude, the movement can be regarded as the translation of the vibration platform 3 in the horizontal direction.

[0048] The embodiment can reduce the influence of other external vibrations on the vibration platform except the excitation source by arranging the elastic structural member 2 between the support rack 1 and the vibration platform, and can simultaneously simulate the vibration generated by the rotation of the seat belt retractor around the X axis and the Z direction excitation by fixing one end of the vibration platform 3 to the elastic structural member 2 of the preset part through the sleeve 4 and fixing the other end of the vibration platform 3 to the elastic structural member 2 of the remaining part, so as to more truly simulate the vibration of the seat belt retractor under the whole vehicle state. Meanwhile, the sleeve shell 42 is rigidly connected to the elastic structural member 2 of the preset part, and the end of the central shaft 41 is rigidly connected to the vibration platform 3, so that when the central shaft 41 and the sleeve shell 42 move relatively around the axis, the vibration platform 3 can rotate around the sleeve 4 and transmit the generated vibration to the vibration platform 3, thereby simulating the vibration generated by the rotation of the seat belt retractor around the X axis. Meanwhile, the central shaft 41 is connected to the elastic structural member 2 of the remaining part through the connecting rod, so as to increase the rigidity of the fixed connection, improve the stability of the testing device, and improve the rationality and accuracy of the abnormal sound test of the seat belt retractor.

[0049] Referring to Figure 3 , the embodiment two of the present application provides a seat belt retractor abnormal sound testing device, which is different from the device in the embodiment one in that:

[0050] The device comprises a support rack composed of a rack mounting surface 11 and five support parts 12, four elastic structural members 2, a vibration platform 3, two sleeves 4, an excitation vibrator 5 and a radio device 6.

[0051] As shown in Figure 3 , the five support parts 12 are fixed on the rack mounting surface 11, of which three support parts are arranged in a row and fixed on one end of the rack mounting surface 11, and two support parts are arranged in a row and fixed on the other end of the rack mounting surface 11.

[0052] The mounting surface 11 is primarily designed to provide a secure mounting surface for the testing equipment. For example, the mounting surface 11 can be a metal floor or other flat and firmly fixed ground. The support frame 1 includes five support sections, and four elastic structural members 2 are respectively fixed to the support sections located at the four corners of the mounting surface 11.

[0053] like Figure 3 As shown, two bushings 4 are fixed to two support parts arranged in a row. As another embodiment, a single bushing 4 can also be used. For example, a bushing 4 can be provided on the right elastic structure 2, and the upper end of the left elastic structure 2 can be movably connected to the vibration table 3. The relative motion between the central shaft 41 in the bushing 4 and the bushing shell 42 around the axis allows the vibration table 3 to rotate around the bushing 4, thereby simulating the vibration generated by the seat belt retractor rotating around the X-axis.

[0054] In one example, such as Figure 4 As shown, the exciter 5 is fixed on the support located in the middle position of the three supports arranged in a row. The exciter 5 is the main excitation of the entire test device. When the exciter 5 provides excitation to the vibration table 3, the vibration table 3 can simultaneously simulate the vibration generated by the seat belt retractor rotating around the X-axis and the Z-axis excitation.

[0055] During the operation of the vibrator 5, the vibration intensity of the vibration table 3 can be controlled by adjusting the operating frequency and excitation force of the vibrator 5. The operating frequency range of the vibrator 5 is [0, 3000] Hz, and the excitation force range is [0, 110] kN.

[0056] In one example, such as Figure 5 As shown, the sound receiving device 6 is fixed on the mounting surface 11 of the platform. In order to improve the sound receiving effect of the sound receiving device 6, the sound receiving device is suspended above the vibration table 3 so as to better collect the sound signal of the seat belt retractor during the operation of the vibrator, and to determine the abnormal noise test results of the seat belt retractor.

[0057] In this embodiment, the testing device is fixed to the mounting surface 11 of the test stand by four equally spaced support parts, providing a solid mounting surface for the testing device and improving its tightness. The exciter 5 of one support part provides excitation to the vibration table 3 to generate vibration and provides a controllable vibration intensity for the vibration table 3. The sound signal of the seat belt retractor is collected by the sound receiving device 6 to determine the abnormal noise test result of the seat belt retractor based on the sound signal, thereby improving the accuracy of the abnormal noise test of the seat belt retractor.

[0058] In other embodiments, the vibrator 5 can be placed in one of the four support sections, instead of having a separate support section for the vibrator 5; it is also possible to... Figure 4Three support parts in the support part are combined into one support part, the left end of the support part is connected with one elastic structure 2, the right end of the support part is connected with another elastic structure 2, and the middle of the support part is placed with a vibration exciter 5.

[0059] On the basis of the above-mentioned test device embodiment, the safety belt retractor abnormal sound test method provided by the third embodiment of the present application can be applied in the application environment of Figure 6 The client and the server communicate with each other. The client includes, but is not limited to, a palm computer, a desktop computer, a notebook computer, an ultra-mobile personal computer (UMPC), a netbook, a cloud computer device, a personal digital assistant (PDA), and the like. The server can be implemented by an independent server or a server cluster composed of multiple servers.

[0060] On the basis of the above-mentioned test device embodiment, the test method can be applied to Figure 7 the client in the application environment, and the test method can include the following steps.

[0061] In step S301, an excitation signal is input to make the safety belt retractor generate vertical vibration and horizontal vibration, and noise signals of the safety belt retractor are collected.

[0062] The excitation signal is generated by an excitation source and is used to make the safety belt retractor generate vertical vibration and horizontal vibration to simultaneously simulate Z-direction excitation of the safety belt retractor and vibration generated by rotation around the X axis, and noise signals of the safety belt retractor are collected to perform abnormal sound test of the safety belt retractor.

[0063] Optionally, the noise signals of the safety belt retractor are collected, including:

[0064] After the excitation signal is input to the vibration exciter for a first preset time, noise signals of the safety belt retractor for a second preset time are collected by a radio device.

[0065] When the abnormal sound test of the safety belt retractor is performed, the noise signals of the safety belt retractor are collected when the vibration exciter works stably in this embodiment, so as to improve the accuracy of the test result. Therefore, after the excitation signal is input to the vibration exciter for a first preset time, the noise signals of the safety belt retractor are collected by the radio device, so as to ensure the stability of the collected noise signals. The first preset time can be set according to actual conditions, for example, the first preset time is 10 seconds.

[0066] Meanwhile, the embodiment sets the radio device to collect the noise signal of the seat belt retractor in the second preset time, so as to reduce the data processing difficulty of the noise signal and improve the work efficiency on the premise of ensuring that the effective noise signal is collected. The second preset time can be set according to the actual situation, for example, the second preset time is 20 seconds.

[0067] In step S302, the noise signal is processed to obtain a high-frequency noise signal.

[0068] The noise signal includes a low-frequency signal and a high-frequency signal, and the noise range of the movable ball of the seat belt retractor is in the high-frequency band. Therefore, the collected noise signal is processed to obtain a high-frequency noise signal to represent the noise of the seat belt retractor, so as to reduce the interference of the low-frequency noise signal and improve the abnormal sound test accuracy of the seat belt retractor.

[0069] In the embodiment, the collected noise signal is processed by a band-pass filter to filter the low-frequency signal and retain the high-frequency signal to obtain a high-frequency noise signal. The start frequency and the cutoff frequency of the band-pass filter can be set according to the actual situation. In the embodiment, the start frequency is set to 1000 Hz and the cutoff frequency is set to 12600 Hz, so the high-frequency noise signal is the noise signal with a frequency in the range of [1000, 12600] Hz.

[0070] In step S303, the noise sound pressure value is calculated according to the high-frequency noise signal, and the noise decibel is calculated according to the noise sound pressure value.

[0071] In order to perform the abnormal sound test of the seat belt retractor, the high-frequency noise signal needs to be converted into a decibel value, and the decibel value is used for the abnormal sound test, so as to reduce the test difficulty, improve the test efficiency and improve the accuracy of the test result.

[0072] Specifically, in the embodiment, the noise sound pressure value is first calculated according to the high-frequency noise signal, and then the noise decibel is calculated according to the noise sound pressure value as the basis for the abnormal sound test of the seat belt retractor.

[0073] Optionally, the noise sound pressure value is calculated according to the high-frequency noise signal, including:

[0074] The sound pressure amplitude of the high-frequency noise signal at the start frequency and the sound pressure amplitude at the cutoff frequency, and the sound pressure amplitude at each of the other frequencies are determined according to the high-frequency noise signal.

[0075] The noise sound pressure value p is calculated according to each sound pressure amplitude. a

[0076]

[0077] ​wherein, α is a preset energy recovery coefficient, j is a starting frequency, k is a cutoff frequency, A i is an amplitude of the sound pressure of the high-frequency noise signal at the i-th frequency, A j is an amplitude of the sound pressure of the high-frequency noise signal at the starting frequency, A k is an amplitude of the sound pressure of the high-frequency noise signal at the cutoff frequency.

[0078] wherein, first, the amplitudes of the sound pressure of the high-frequency noise signal at the starting frequency and at the cutoff frequency, and at each of the other frequencies are determined according to the high-frequency noise signal, so that the noise sound pressure value p a is calculated.

[0079]

[0080] wherein, α is a preset energy recovery coefficient, j is a starting frequency, k is a cutoff frequency, A i is an amplitude of the sound pressure of the high-frequency noise signal at the i-th frequency, A j is an amplitude of the sound pressure of the high-frequency noise signal at the starting frequency, A k is an amplitude of the sound pressure of the high-frequency noise signal at the cutoff frequency.

[0081] In the embodiment, the starting frequency of the band-pass filter is set to j = 1000 Hz, and the cutoff frequency is set to k = 12600 Hz.

[0082] Optionally, the noise decibel is calculated according to the noise sound pressure value, including:

[0083] According to the conversion relationship between the sound pressure and the decibel, the noise decibel is calculated according to the noise sound pressure value.

[0084] wherein, the sound pressure value is converted into the decibel value according to the conversion relationship between the sound pressure and the decibel, and the noise decibel is calculated according to the noise sound pressure value p a .

[0085]

[0086] wherein, p a is the noise sound pressure value, p ref is a standard value of the sound pressure, in the embodiment, p ref = 2 x 10 -5 .

[0087] Step S304, determining the abnormal sound test result of the safety belt retractor according to the noise decibel.

[0088] wherein, the greater the noise decibel, the greater the noise of the safety belt retractor during the vibration process, and the smaller the noise decibel, the smaller the noise of the safety belt retractor during the vibration process.

[0089] In the embodiment, the abnormal sound test result of the seat belt retractor is determined according to the size of the noise decibel, wherein the abnormal sound test result includes two kinds, existence of abnormal sound and non-existence of abnormal sound, therefore, the larger the noise decibel is, the greater the possibility of existence of abnormal sound of the seat belt retractor is, and when the noise decibel is greater than the preset decibel threshold, it is judged that the seat belt retractor exists abnormal sound.

[0090] Optionally, the abnormal sound test result of the seat belt retractor is determined according to the noise decibel, including:

[0091] The noise decibel is compared with the preset decibel threshold;

[0092] If the noise decibel is less than the decibel threshold, the abnormal sound test result of the seat belt retractor is determined as non-existence of abnormal sound;

[0093] If the noise decibel is not less than the decibel threshold, the abnormal sound test result of the seat belt retractor is determined as existence of abnormal sound.

[0094] Wherein, the calculated noise decibel is compared with the preset decibel threshold, if the noise decibel is less than the decibel threshold, the abnormal sound test result of the seat belt retractor is determined as non-existence of abnormal sound, if the noise decibel is not less than the decibel threshold, the abnormal sound test result of the seat belt retractor is determined as existence of abnormal sound, and the abnormal sound test of the seat belt retractor is completed. The preset decibel threshold can be determined according to actual conditions, and in the embodiment, the preset decibel threshold is 38 dB.

[0095] In the embodiment, the vertical vibration and the horizontal vibration of the seat belt retractor are generated by inputting the excitation signal, the noise signal of the seat belt retractor is collected, the noise signal is signal-processed to obtain the high-frequency noise signal, the noise sound pressure value is calculated according to the high-frequency noise signal, the noise decibel is calculated according to the noise sound pressure value, and finally the abnormal sound test result of the seat belt retractor is determined according to the noise decibel. The interference of the low-frequency noise signal is reduced by signal-processing the collected noise signal, the high-frequency noise signal meeting the noise range of the seat belt retractor is obtained, and the accuracy of the abnormal sound test of the seat belt retractor is improved.

[0096] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features thereof; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A device for testing abnormal noise in a seatbelt retractor, characterized in that, The testing device includes a support frame, at least one elastic structural component, a vibration table, and a bushing. Each of the elastic structural components is fixed to a corresponding support portion of the support frame, and the bushing is fixed to the elastic structural component of the preset portion. One end of the vibration table is fixed to the elastic structure of the preset part by a bushing, and the other end of the vibration table is fixed to the elastic structure of the remaining part. The vibration table is used to vibrate vertically under the excitation of an excitation source when performing abnormal noise tests on the seat belt retractor, and to rotate about the bushing axis to simulate horizontal vibration.

2. The testing apparatus as described in claim 1, characterized in that, The bushing includes a central shaft and a bushing housing; The central shaft is disposed inside the bushing housing, and the central shaft is connected to the bushing housing via rubber. The bushing housing is rigidly connected to the elastic structural member in the preset portion, and the end of the central shaft is rigidly connected to the vibration table.

3. The testing apparatus as described in claim 2, characterized in that, The two ends of the central shaft are connected to the remaining elastic structural members via connecting rods.

4. The testing apparatus as described in claim 1, characterized in that, The elastic structural component is an air spring.

5. The testing apparatus as described in claim 1, characterized in that, The support frame includes a frame mounting surface and a plurality of support parts, each of which is fixed to the frame mounting surface.

6. The testing apparatus as described in claim 5, characterized in that, The testing device also includes a vibrator, which is fixed on a corresponding support portion of the support frame.

7. The testing apparatus as described in claim 5, characterized in that, The testing apparatus also includes a radio receiver, which is fixed to the mounting surface of the test stand.

8. A method for testing abnormal noise in a seatbelt retractor, characterized in that, The seatbelt retractor is tested using the testing apparatus as described in any one of claims 1-7, and the testing method includes: An input excitation signal is used to cause the seat belt retractor to vibrate vertically and horizontally, and the noise signal of the seat belt retractor is collected. The noise signal is processed to obtain a high-frequency noise signal; Calculate the noise sound pressure value based on the high-frequency noise signal, and calculate the noise decibel based on the noise sound pressure value; The abnormal noise test result of the seat belt retractor is determined based on the noise level in decibels.

9. The test method as described in claim 8, characterized in that, The noise signal of the seatbelt retractor is collected, including: The testing device also includes a vibrator, which is fixed on a corresponding support part of the support frame. After the excitation signal is input to the vibrator for a first preset time, the noise signal of the seat belt retractor is collected by a radio device for a second preset time.

10. The test method as described in claim 8, characterized in that, The step of calculating the noise sound pressure level based on the high-frequency noise signal includes: The sound pressure amplitude of the high-frequency noise signal at the starting frequency and the sound pressure amplitude at the cutoff frequency, as well as the sound pressure amplitude at each of the other frequencies, are determined based on the high-frequency noise signal. The noise sound pressure value is calculated based on each of the aforementioned sound pressure amplitudes. for: In the formula, Here, j is the preset energy recovery coefficient, j is the starting frequency, and k is the cutoff frequency. Let be the sound pressure amplitude of the high-frequency noise signal at the i-th frequency. The sound pressure level of the high-frequency noise signal at the starting frequency. The sound pressure amplitude of the high-frequency noise signal at the cutoff frequency is denoted as .

11. The test method as described in claim 8, characterized in that, The step of calculating the noise decibels based on the noise sound pressure value includes: Based on the conversion relationship between sound pressure and decibels, and combined with the noise sound pressure value, the noise decibels are calculated.

12. The test method as described in claim 8, characterized in that, The step of determining the abnormal noise test result of the seat belt retractor based on the noise decibels includes: The noise level in decibels is compared with a preset decibel threshold. If the noise level is less than the decibel threshold, the abnormal noise test result of the seat belt retractor is determined to be that there is no abnormal noise. If the noise level is not less than the decibel threshold, the abnormal noise test result of the seat belt retractor is determined to be that abnormal noise exists.

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