Fastener anti-loosening performance testing device

Abstract

The utility model discloses a fastener anti-loosening performance testing device, which comprises a test clamp, an attachment plate, a vibration platform and a force sensor, and is characterized in that the vibration platform drives the test clamp, the attachment plate and a tested fastener to vibrate synchronously, and the vibration frequency and the excitation acceleration of the vibration platform are consistent with the vibration frequency and the excitation acceleration of an actual application environment; a vibration environment for testing the anti-loosening performance is provided for the tested fastener; the fixed frequency of the attachment plate is the same as the preset vibration frequency of the vibration platform, the attachment plate can resonate with the vibration platform, and the attachment plate provides transverse alternating stress for the tested fastener. Through cooperation of the vibration platform and the attachment plate, the test environment of the tested fastener can be equivalent to the actual application environment of the fastener, and the transverse alternating stress, from the attachment plate, borne by the tested fastener can be obtained through calculation. The anti-loosening performance test and the fatigue life evaluation of the tested fastener under the conditions of quantitative vibration frequency, excitation acceleration and transverse alternating stress are realized.

Description

Technical Field

[0001] The present application relates to the technical field of transformers, and in particular to a fastener anti-loosening performance testing device. Background Art

[0002] Fasteners consisting of bolts and nuts are a commonly used fastening method in mechanical equipment and are also widely used in transformer products.

[0003] The fasteners used in transformer products are exposed to electromagnetically induced 100Hz 0.2g~2g sinusoidal vibration environment for a long time, and are subjected to lateral alternating stress. Fasteners are prone to problems such as connection fatigue relaxation and insufficient clamping force, which affect the reliability and service life of transformer products. Therefore, it is of great significance to conduct anti-loosening tests on fasteners under vibration environment and alternating stress, and to estimate fatigue life.

[0004] Therefore, how to conduct quantitative anti-loosening tests on fasteners under vibration environments and alternating stresses has become a technical problem that needs to be urgently solved by those skilled in the art. Utility Model Content

[0005] The present application proposes a fastener anti-loosening performance testing device to perform a quantitative anti-loosening test on the fastener under a vibration environment and alternating stress.

[0006] In order to achieve the above-mentioned purpose, the present application provides a fastener anti-loosening performance testing device, including a test fixture, an attachment plate, a vibration platform and a force sensor.

[0007] The test fixture is vertically mounted on the vibration platform, and the vibration platform is used to generate vibration with a preset frequency and a preset excitation acceleration, and drive the test fixture to vibrate.

[0008] The test fixture and the attachment plate are located in the same plane, the attachment plate is connected to the end of the test fixture away from the vibration platform through a tested fastener, the end of the attachment plate away from the test fixture is suspended, and the natural frequency of the attachment plate is the same as the preset frequency.

[0009] The force sensor is arranged on the tested fastener and is used to detect the fastening force of the bolt head of the tested fastener acting on the test fixture.

[0010] Preferably, in the above-mentioned fastener anti-loosening performance testing device, the attachment plate is provided at one or more positions of the test fixture.

[0011] Preferably, in the above-mentioned fastener anti-loosening performance testing device, the diameters of the mounting holes of two adjacent attachment plates used for connecting with the fastener to be tested are equal or unequal.

[0012] Preferably, in the above-mentioned fastener anti-loosening performance testing device, the attached plate is connected to the vibration platform through a fixing member, and the fixing member is perpendicular to the test fixture.

[0013] A reinforcing member is also included, and the reinforcing member is located between the test fixture and the fixing member and is used to support the test fixture.

[0014] Preferably, the above-mentioned fastener anti-loosening performance testing device further includes a vibration controller and an acceleration sensor.

[0015] The acceleration sensor is arranged on the vibration platform, the bolt head of the tested fastener and the attachment plate, and the acceleration sensor is communicatively connected with the vibration controller.

[0016] Preferably, in the above-mentioned fastener anti-loosening performance testing device, the acceleration sensor is arranged at one end of the attachment plate away from the test fixture.

[0017] Preferably, in the above-mentioned fastener anti-loosening performance testing device, at least half of the attached plate along its own length direction protrudes from the end of the test fixture away from the vibration platform.

[0018] Preferably, the above-mentioned fastener anti-loosening performance testing device also includes a data acquisition device, which is communicatively connected with the force sensor.

[0019] Preferably, in the above-mentioned fastener anti-loosening performance testing device, the attached plate is a rigid plate.

[0020] The fastener anti-loosening performance test device provided in the embodiment of the present application includes a test fixture, an attached plate, a vibration platform and a force sensor. The vibration platform drives the test fixture, the attached plate and the tested fastener to vibrate synchronously. The vibration frequency and excitation acceleration of the vibration platform are consistent with the vibration frequency and excitation acceleration of the actual application environment, providing a vibration environment for the tested fastener to test the anti-loosening performance; the fixed frequency of the attached plate is the same as the preset frequency of the vibration platform vibration, the attached plate can resonate with the vibration platform, and the attached plate provides transverse alternating stress to the tested fastener. The present application makes the test environment of the tested fastener equivalent to the actual application environment of the fastener by cooperating with the vibration platform and the attached plate. At the same time, the transverse alternating stress from the attached plate that the tested fastener bears can be obtained by calculation, so as to realize the anti-loosening performance test of the tested fastener under the conditions of quantitative vibration frequency, excitation acceleration and transverse alternating stress, as well as fatigue life evaluation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without creative work, and the present application can also be applied to other similar scenarios based on the provided drawings. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0022] Figure 1 It is a structural schematic diagram of the fastener anti-loosening performance testing device of the present application;

[0023] Figure 2 is along Figure 1 Schematic diagram of the structure of the device for testing the anti-loosening performance of fasteners in the middle A direction (vibration platform is not shown);

[0024] Figure 3 It is a side view of the fastener anti-loosening performance testing device of the present application (vibration platform is not shown).

[0025] The accompanying drawings are as follows:

[0026] 1-test fixture; 2-attachment plate; 3-vibration platform; 4-force sensor; 5-test fastener; 6-fixing piece; 7-reinforcement piece; 8-vibration controller; 9-acceleration sensor; 10-data acquisition instrument. DETAILED DESCRIPTION

[0027] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It will be understood that the specific embodiments described herein are only used to explain the related application, rather than to limit the application. The described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0028] It should be noted that, for ease of description, only the parts related to the relevant applications are shown in the accompanying drawings. In the absence of conflict, the embodiments in this application and the features in the embodiments can be arbitrarily combined with each other, as long as the combined technical features are not contradictory. All feasible feature combinations are technical contents clearly recorded in this article. Any of the multiple sub-features contained in the same sentence can be applied independently, and does not have to be applied together with other sub-features.

[0029] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The elements defined by the sentence "includes a..." do not exclude the existence of other identical elements in the process, method, commodity or device that includes the elements.

[0030] In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0031] Some related technologies disclose that the anti-loosening performance test of the tested fasteners is carried out by a fastener lateral vibration tester, and the anti-loosening characteristics of the threaded fasteners are judged by analyzing the change curves of the pre-tightening axial force, lateral displacement and lateral vibration period of the tested fasteners by the lateral vibration tester. The fastener lateral vibration tester can produce lateral alternating displacements that cause the tested fasteners to loosen, record the instantaneous value of the clamping force, and determine the anti-loosening performance of the fasteners based on the recorded results. However, the vibration frequency that the fastener lateral vibration tester can provide is 3Hz-15Hz, which can only be used as a basis for evaluating the anti-loosening performance of the tested fasteners under the vibration frequency condition of 3Hz-15Hz.

[0032] Some other related technologies disclose the use of a vibration table and a test fixture to test the anti-loosening performance of the test fastener. The test fastener is tightened on the test fixture according to a preset torque, and then the test fixture and the test fastener are fixed on the vibration table. The test fixture and the test fastener work as a whole with the vibration table according to the set frequency and amplitude until the required time or number of vibration cycles. This technology only considers the anti-loosening performance of the test fastener itself in a vibration environment, but does not consider the impact of the lateral movement of the parts connected to the test fastener on the anti-loosening performance of the test fastener. The test conditions of the above-mentioned related technologies are a vibration frequency of 30Hz and a full amplitude of 11.43±4mm, which can only be used as a basis for lateral comparison and evaluation of different test fasteners under the test conditions, and cannot reflect the impact of lateral alternating stress on the anti-loosening effect of the test fastener, especially large-tonnage parts.

[0033] See also Figure 1-Figure 3 .

[0034] Some embodiments of the present application disclose a fastener anti-loosening performance testing device, comprising a test fixture 1, an attachment plate 2, a vibration platform 3 and a force sensor 4.

[0035] The test fixture 1 is vertically mounted on the vibration platform 3, which is used to generate vibrations of a preset frequency and a preset excitation acceleration, and drive the test fixture 1 to vibrate synchronously. The vibration frequency and excitation acceleration of the vibration platform 3 can be adjusted according to actual needs so that the vibration platform 3 meets the requirements of different test environments. For example, the vibration environment of transformer products is a 100Hz sinusoidal vibration environment, and accordingly, the vibration provided by the vibration platform 3 is also a 100Hz sinusoidal vibration environment.

[0036] The attachment plate 2 and the test fixture 1 are located in the same plane. After the attachment plate 2 is connected to the test fixture 1, the attachment plate 2 is also perpendicular to the vibration platform 3. The first end of the attachment plate 2 is connected to the end of the test fixture 1 away from the vibration platform 3 through the test fastener 5, and the second end of the attachment plate 2 away from the test fixture 1 is suspended in the air. The attachment plate 2 vibrates synchronously with the test fixture 1.

[0037] In this solution, the natural frequency of the attachment plate 2 is the same as the preset frequency of the vibration platform 3, so that the attachment plate 2 can resonate with the vibration platform 3. The attachment plate 2 is used to provide transverse alternating stress to the tested fastener 5 to simulate the transverse alternating stress provided to the fastener by the parts fixed by fasteners in transformer products. Specifically, the first end of the attachment plate 2 is fixedly connected to the test fixture through the tested fastener, and the second end of the attachment plate 2 away from the test fixture is suspended in the air. When the attachment plate 2 resonates with the vibration platform 3, the maximum vibration displacement point of the first-order vibration mode of the attachment plate 2 is located at the second end of the attachment plate 2. The transverse alternating stress generated by the resonance at the second end of the attachment plate 2 is transmitted to the first end of the attachment plate 2. According to the principle of lever, the tested fastener 5 needs to apply a large torque to the test fixture to ensure the connection between the test fixture 1 and the attachment plate 2.

[0038] The natural frequency of the attachment plate 2 and the preset frequency of the vibration platform vibration are designed to be consistent, so that the attachment plate 2 and the vibration platform 3 can resonate, and a sufficiently large lateral alternating stress can be obtained by using the attachment plate 2 with a small size and small mass.

[0039] Due to the resonance of the attached plate 2 and the vibration platform 3, the transverse alternating stress provided by the attached plate 2 of the fastener anti-loosening performance testing device to the tested fastener 5 will be greater than or equal to the transverse alternating stress provided by the components fixed by fasteners in transformer products to the fasteners. The anti-loosening performance tested under the action of this transverse alternating stress is lower than the anti-loosening performance of the fasteners actually used in transformer products, thereby obtaining the lower limit of the anti-loosening performance.

[0040] In this solution, the auxiliary plate 2 resonates with the vibration platform 3, so that the auxiliary plate 2 provides the tested fastener 5 with a transverse alternating stress. There is no need to separately set up a structure for providing the transverse alternating stress, thus simplifying the overall structure of the fastener anti-loosening performance testing device.

[0041] The natural frequency is the inherent characteristic of the system, and is related to mass, shape and material.

[0042] The design steps of the attachment plate 2 are as follows: first, a three-dimensional model of the test fixture 1 and the attachment plate 2 is established; then, the three-dimensional model of the test fixture 1 and the three-dimensional model of the attachment plate 2 are bound and connected at the openings thereof by using simulation software; then, according to the relationship between the natural frequency of the attachment plate 2 and the preset frequency, the mass and / or the external dimensions of the attachment plate 2 are designed, and the external dimensions and mass of the attachment plate 2 are designed. In some embodiments of the present scheme, the attachment plate 2 is in the shape of a strip, and the shape of the attachment plate 2 is determined by the length, width and thickness of the attachment plate 2. The attachment plate 2 is described as a strip structure in the following text, but the shape of the attachment plate 2 is not limited to a strip.

[0043] In some embodiments, the width and thickness of the attachment plate 2 suitable for different test environments are equal to reduce the installation requirements of the test fixture 1 in the width and thickness directions of the attachment plate 2. In this embodiment, the natural frequency of the attachment plate 2 is related to the length and mass of the attachment plate 2, and the natural frequency of the attachment plate 2 is changed by changing the length and / or mass of the attachment plate 2. Specifically, increasing the mass of the attachment plate 2 and / or reducing the length of the attachment plate 2 can reduce the natural frequency of the attachment plate 2, and reducing the mass of the attachment plate 2 and / or increasing the length of the attachment plate 2 can increase the natural frequency of the attachment plate 2. In this embodiment, the adjustment of the mass of the attachment plate 2 can be achieved by selecting attachment plates of different materials.

[0044] In other embodiments, the width of the attachment plate 2 suitable for different test environments and the material of the attachment plate 2 are the same. In this embodiment, the natural frequency of the attachment plate 2 is related to the length and thickness of the attachment plate 2, and the natural frequency of the attachment plate 2 is changed by changing the length and / or thickness of the attachment plate 2. Specifically, increasing the thickness of the attachment plate 2 and / or reducing the length of the attachment plate 2 can reduce the natural frequency of the attachment plate 2, and reducing the thickness of the attachment plate 2 and / or increasing the length of the attachment plate 2 can increase the natural frequency of the attachment plate 2.

[0045] It should be noted here that the length of the attached plate 2 is the dimension of the attached plate 2 along the direction perpendicular to the surface of the vibration platform 3 for installing the test fixture 1, the thickness of the attached plate 2 is the dimension of the attached plate 2 along the direction perpendicular to the plane where the test fixture 1 is located, the width of the attached plate 2 is the dimension of the attached plate 2 along the direction parallel to the plane where the test fixture 1 is located, and the first end and the second end of the attached plate 2 are respectively the two ends of the length direction of the attached plate 2.

[0046] The tested fastener 5 includes a bolt and a nut, and the bolt is locked with the nut. The attachment plate 2 is arranged on one side of the test fixture 1, and the attachment plate 2 and the test fixture 1 are provided with mounting holes corresponding to and connected to each other. After the bolt of the tested fastener 5 passes through the mounting holes of the test fixture 1 and the attachment plate 2 in turn, the bolt is locked on the test fixture 1 and the attachment plate 2 by the nut. The bolt head of the bolt is located on the side of the test fixture 1 where the attachment plate 2 is not arranged, and the nut is located on the side of the attachment plate 2 away from the test fixture 1.

[0047] Under the transverse alternating stress provided by the attachment plate 2, the tightening force of the tested fastener gradually decreases or even fails. The force sensor 4 is installed between the bolt head and the test fixture 1 to detect the tightening force applied by the bolt head of the tested fastener 5 on the test fixture 1. The force sensor 4 can collect the tightening force in real time to monitor the instantaneous change value of the tightening force of the tested fastener 5.

[0048] The fastener anti-loosening performance test device disclosed in the present application, the vibration platform 3 drives the test fixture 1, the attached plate 2 and the tested fastener 5 to vibrate synchronously, the vibration frequency and excitation acceleration of the vibration platform 3 are consistent with the vibration frequency and excitation acceleration of the actual application environment, and provide a vibration environment for the tested fastener 5 to test the anti-loosening performance; the fixed frequency of the attached plate 2 is the same as the preset frequency of the vibration of the vibration platform 3, the attached plate 2 can resonate with the vibration platform 3, and the attached plate 2 provides transverse alternating stress to the tested fastener 5. The present application realizes the anti-loosening test of the fastener under the vibration environment and alternating stress by cooperating with the vibration platform 3 and the attached plate 2, so that the test environment of the tested fastener 5 can be equivalent to the actual application environment of the fastener, and at the same time, the transverse alternating stress from the attached plate 2 that the tested fastener bears can be obtained by calculation, so as to realize the anti-loosening performance test of the tested fastener under the conditions of quantitative vibration frequency, excitation acceleration and transverse alternating stress, as well as fatigue life evaluation.

[0049] The transverse alternating stress provided by the attachment plate 2 to the tested fastener 5 is determined by the length and mass dimensions of the attachment plate 2 .

[0050] In some embodiments, the steps for obtaining the transverse alternating stress from the attachment plate 2 borne by the tested fastener are as follows:

[0051] Obtain the excitation acceleration a of the second end of the attachment plate 2, and calculate the first transverse alternating stress F1 of the second end of the attachment plate 2 in combination with Newton's second theorem F1=ma, where m is the mass of the attachment plate 2, which can be obtained during the design process of the attachment plate 2;

[0052] The first transverse alternating stress F1 generated at the second end of the attachment plate 2 is transmitted to the first end of the attachment plate 2. The transverse alternating stress F2 (hereinafter referred to as the second transverse alternating stress) borne by the first end of the attachment plate 2 can be calculated according to the lever principle. The calculation formula of the second transverse alternating stress F2 at the second end of the attachment plate 2 is: Wherein, L1 is the distance between the second end of the attachment plate 2 and the end of the test fixture 1 away from the vibration platform 3, L2 is the distance between the position where the attachment plate 2 is flush with the end of the test fixture 1 away from the vibration platform 3 and the axis of the tested fastener 5, and L3 is the distance between the axis of the tested fastener 5 and the first end of the attachment plate 2. Figure 3 As shown, the sum of the lengths of L1, L2 and L3 is the length of the attachment plate 2, and the length of the attachment plate 2 can be obtained during the design process of the attachment plate 2.

[0053] This solution provides an anti-loosening performance test device that has the same vibration frequency and excitation acceleration as the application environment and provides quantitative lateral alternating stress to the tested fasteners, providing quantitative judgment indicators for the anti-loosening performance test of fasteners in the operating environment.

[0054] Combining the excitation acceleration g0 of the vibration platform and the excitation acceleration g1 of the tested fastener, as well as the failure time T1 of the tested fastener 5, according to the equivalent formula of sinusoidal vibration fatigue damage and vibration durability test (g0 / g1)=(T1 / T0)1 / 6, the fatigue life time T0 of the tested fastener under the long-term g0 vibration environment and stress F2 can be calculated, thereby realizing the quantitative calculation of the fastener fatigue life.

[0055] In some embodiments, one or more attachment plates 2 are provided on the test fixture 1, each attachment plate 2 is installed at a different position of the test fixture 1, and each attachment plate 2 is connected to the test fixture 1 through a test fixture 6. Considering the need to provide multiple attachment plates 2 on the test fixture 1, in order to reduce interference between adjacent attachment plates 2, the widths of the multiple attachment plates 2 are equal.

[0056] Optionally, the plurality of attachment plates 2 are all disposed at one end of the test fixture 1 away from the vibration platform 3 , the plurality of attachment plates 2 are arranged at equal or unequal heights, and / or the plurality of attachment plates 2 are distributed on the vibration platform 3 at equal or unequal intervals.

[0057] During the test process, the fastener anti-loosening performance testing device can simultaneously perform anti-loosening performance tests on multiple test fasteners 5 fastened on the test fixture 1. The multiple test fasteners 5 can be the same type of test fasteners or different types of test fasteners.

[0058] In an embodiment where the multiple tested fasteners 5 are of the same type, the anti-loosening performance of the multiple tested fasteners 5 obtained through testing can be compared to verify the anti-loosening performance test results and improve the reliability of the anti-loosening performance test.

[0059] In an embodiment where the multiple tested fasteners 5 are of different types, the anti-loosening performance test can be performed on at least two tested fasteners 5 at the same time under the same vibration environment and the same or different lateral alternating stresses. Compared with a method in which the anti-loosening performance test can only be performed on one tested fastener 5 at a time, the efficiency is relatively improved.

[0060] The test fixture 1 and the vibration platform 3 may be directly connected, or they may be connected via a fixing member 6. The fixing member 6 may be a fixing plate, a fixing rod, a fixing bracket, or the like.

[0061] In some embodiments, the test fixture 1 is connected to the vibration platform 3 via a fixing plate. Figure 2 As shown, the fixing plate has a certain length in the direction perpendicular to the plane where the test fixture 1 is located, which can increase the connection area and connection position of the test fixture 1 and the vibration platform 3, and improve the stability of the connection between the test fixture 1 and the vibration platform 3. Optionally, the length of the fixing plate in the direction perpendicular to the plane where the test fixture 1 is located is at least equal to the length of the test fixture 1 in the direction perpendicular to the vibration platform 3, so that the mass and area of ​​the fixing plate are greater than the mass of the test fixture 1, and the stability of the connection between the test fixture 1 and the vibration platform 3 is improved.

[0062] In some embodiments, the test fixture 1 is connected to the vibration platform 3 through a fixing rod, and the fixing rod is arranged in a direction perpendicular to the plane where the test fixture 1 is located, and along the length direction of the test fixture 1, the fixing rod can be arranged only at the two ends of the length direction of the test fixture 1, and the fixing rod can also be arranged in the middle and both ends of the length direction of the test fixture 1. The length direction of the test fixture 1 is as follows: Figure 2 As shown, the arrangement direction of multiple attachment plates 2 on the test fixture 1.

[0063] In some embodiments, the test fixture 1 is connected to the vibration platform 3 through a fixed bracket, and optionally, the fixed bracket is a closed hollow bracket to ensure the strength of the fixed bracket itself. The fixed bracket is arranged in a direction perpendicular to the plane where the test fixture 1 is located, and the positions of the fixed points of the fixed bracket and the vibration platform 3 are increased, thereby enhancing the connection strength between the test fixture 1 and the vibration platform 3.

[0064] In some embodiments, the test fixture 1 and the fixing member 6 are welded into an integrated structure to reduce the loosening of the connection structure between the fixing member 6 and the vibration platform 3 caused by vibration.

[0065] In some embodiments, the fastener anti-loosening performance testing device further includes a reinforcement member 7 , and the reinforcement member 7 is used to support the test fixture 1 to improve the working strength of the test fixture 1 .

[0066] The reinforcement member 7 may be a reinforcement plate, a reinforcement rod or a reinforcement bracket, etc. The reinforcement member 7 is located between the test fixture 1 and the fixing member 6 .

[0067] like Figure 3 As shown, in an embodiment where the reinforcement member 7 is a reinforcement rod, one end of the reinforcement rod is connected to the end of the test fixture 1 away from the vibration platform 3, and the other end of the reinforcement rod is connected to the end of the fixing member 6 away from the test fixture 1, and the reinforcement rod forms a certain angle with the plane where the test fixture 1 is located.

[0068] The cooperation among the reinforcing member 7 , the fixing member 6 and the test fixture 1 improves the working stability of the test fixture 1 .

[0069] The whole consisting of the reinforcement member 7, the fixing member 6 and the test fixture 1 is installed on the vibration platform 3, and the reinforcement member 7, the fixing member 6 and the test fixture 1 vibrate synchronously. Optionally, the whole consisting of the reinforcement member 7, the fixing member 6 and the test fixture 1 does not resonate with the vibration platform 3 to reduce the impact on the connection stability between the reinforcement member 7, the fixing member 6 and the test fixture 1 and between the fixing member 6 and the vibration platform 3.

[0070] In some embodiments, the excitation acceleration of the vibration platform 3, the excitation acceleration of the bolt head of the tested fastener 5, and the excitation acceleration of the attached plate 2 can be obtained by the acceleration sensor 9. In this solution, the acceleration sensor 9 for monitoring the excitation acceleration of the vibration platform 3 is integrated on the vibration platform 3, the acceleration sensor 9 for monitoring the excitation acceleration of the tested fastener 5 is integrated on the bolt head of the tested fastener 5, and the acceleration sensor 9 for monitoring the excitation acceleration of the attached plate 2 is integrated on the attached plate 2, and the acceleration sensor 9 is communicatively connected to the vibration controller 8.

[0071] The vibration controller 8 can be integrated into the fastener anti-loosening performance test device or can exist independently. The staff reads the excitation acceleration values ​​of the vibration platform 3, the bolt head of the tested fastener 5 and the attachment plate 2 through the vibration controller 8.

[0072] When the excitation acceleration of the vibration platform 3 monitored by the acceleration sensor 9 disposed on the vibration platform 3 is the same as the excitation acceleration of the attachment plate 2 monitored by the acceleration sensor 9 disposed on the attachment plate 2 , the vibration platform 3 resonates with the attachment plate 2 .

[0073] In some embodiments, an acceleration sensor 9 is disposed at one end of the attachment plate 2 away from the test fixture 1 , so as to improve the accuracy of the excitation acceleration acquisition of the attachment plate 2 to a certain extent.

[0074] In some embodiments, at least half of the attachment plate 2 along its length direction protrudes from the end of the test fixture 1 away from the vibration platform 3, and the first transverse alternating stress F1 is designed to be at least half of the tightening force of the tested fastener 5.

[0075] In some embodiments, the fastener anti-loosening performance testing device disclosed in the present solution further includes a data acquisition device 10. In this embodiment, the data acquisition device 10 acquires the fastening force of the tested fastener 5 in real time and displays the acquired fastening force.

[0076] In the early stage of the test, the tightening force of the tested fastener 5 is collected by the data acquisition instrument 10 to determine whether the tested fastener 5 reaches the tightening force value required by the technical conditions; during the test, the tightening force of the tested fastener 5 is collected in real time by the data acquisition instrument 10 to facilitate the staff to observe the condition of the tested fastener 5.

[0077] The data acquisition instrument 10 can also display a tightening force curve, through which the anti-loosening performance of the fastener can be obtained, and the staff can obtain the failure time T1 of the tested fastener 5 according to the tightening force curve. Among them, T1 starts from the start of the vibration platform.

[0078] The method of acquiring the failure time T1 of the tested fastener 5 is not limited to the data acquisition device 10 , and may be other methods, which are not specifically limited here.

[0079] The attachment plate 2 is preferably made of a material with a certain rigidity so that the attachment plate 2 can rebound quickly when resonating with the vibration platform 3, thereby shortening the response time.

[0080] In some embodiments, the attachment plate 2 is a metal plate or a hard plastic plate.

[0081] The specific steps of the test method for the anti-loosening performance of fasteners are as follows:

[0082] S1, establishing a three-dimensional model of the test fixture 1 and the attached plate 2, and using simulation software to bind and connect the three-dimensional model of the test fixture 1 and the three-dimensional model of the attached plate 2 at the opening, and according to the relationship that the natural frequency of the attached plate 2 is equal to the preset frequency, designing the mass and / or external dimensions of the attached plate 2, obtaining the mass and external dimensions of the attached plate 2, and processing the attached plate 2;

[0083] S2, fix the test fixture 1 on the vibration platform 3;

[0084] S3, the attachment plate 2 is assembled with the test fixture 1 through the tested fastener 5, and the force sensor 4 is installed on the bolt head of the tested fastener 5;

[0085] S4, tighten the tested fastener 5 until the fastening force of the tested fastener 5 collected by the data acquisition device 10 reaches a preset fastening force;

[0086] S5, the vibration platform 3 is started, and the excitation acceleration a of the second end of the attachment plate 2, the excitation acceleration g0 of the vibration platform and the excitation acceleration g1 of the tested fastener are obtained, and at the same time, the data acquisition instrument 10 generates a fastening force curve of the tested fastener 5;

[0087] S6, the vibration platform 3 stops working after a preset time, and the failure time T1 of the tested fastener 5 is obtained according to the fastening force curve;

[0088] S7, obtaining the second transverse alternating stress of the attachment plate 2 acting on the tested fastener 5,

[0089] Combining the corresponding relationship F1=ma between the excitation acceleration a of the attachment plate 2 and the mass m of the attachment plate 2 and the first transverse alternating stress F1 at the second end of the attachment plate 2, the first transverse alternating stress F1 is obtained;

[0090] Combined with the first distance L1 between the second end of the attachment plate 2 and the second end of the attachment plate 2 corresponding to the test platform away from the vibration platform 3, the second distance L2 between the second end of the attachment plate 2 and the axis of the tested fastener 5, and the third distance L3 between the axis of the tested fastener 5 and the first end of the attachment plate 2, the corresponding relationship between the first transverse alternating stress F1 and the second transverse alternating stress F2 of the tested fastener 5 acting on the attachment plate 2 The second transverse alternating stress F2 of the tested fastener 5 acting on the attachment plate 2 is obtained;

[0091] S8, combining the excitation acceleration g0 of the vibration platform, the excitation acceleration g1 of the tested fastener, the corresponding relationship between the failure time T1 of the tested fastener 5 and the fatigue life time T0 (g0 / g1) = (T1 / T0)1 / 6,

[0092] The fatigue life time T0 of the tested fastener 5 under the long-term conditions of the preset vibration frequency, the excitation acceleration g0 and the transverse alternating stress F2 is obtained.

[0093] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used, and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. The scope of application involved in the present application is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but should also cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the above-mentioned application concept. For example, the above-mentioned features are replaced with the technical features with similar functions disclosed in this application (but not limited to) to form a technical solution.

Claims

1. A fastener anti-loosening performance testing device, characterized in that: It comprises a test fixture (1), an attachment plate (2), a vibration platform (3) and a force sensor (4), The test fixture (1) is vertically mounted on the vibration platform (3), and the vibration platform (3) is used to generate vibrations of a preset frequency and a preset excitation acceleration, and drive the test fixture (1) to vibrate. The test fixture (1) and the attachment plate (2) are located in the same plane, the attachment plate (2) is connected to the end of the test fixture (1) away from the vibration platform (3) through a test fastener (5), the end of the attachment plate (2) away from the test fixture (1) is suspended, and the natural frequency of the attachment plate (2) is the same as the preset frequency. The force sensor (4) is mounted on the tested fastener (5) and is used to detect the tightening force exerted by the bolt head of the tested fastener (5) on the test fixture (1).

2. The fastener anti-loosening performance testing device according to claim 1, characterized in that: The attachment plate (2) is arranged at one or more positions of the test fixture (1).

3. The fastener anti-loosening performance testing device according to claim 2, characterized in that: The diameters of the mounting holes of two adjacent attachment plates (2) for connection with the tested fasteners (5) are equal or unequal.

4. The fastener anti-loosening performance testing device according to any one of claims 1 to 3, characterized in that: The attachment plate (2) is connected to the vibration platform (3) via a fixing member (6), and the fixing member (6) is perpendicular to the test fixture (1). It also comprises a reinforcing member (7), wherein the reinforcing member (7) is located between the test fixture (1) and the fixing member (6) and is used to support the test fixture (1).

5. The fastener anti-loosening performance testing device according to any one of claims 1 to 3, characterized in that: It also includes a vibration controller (8) and an acceleration sensor (9), The vibration platform (3), the bolt head of the tested fastener (5) and the attachment plate (2) are all provided with the acceleration sensor (9), and the acceleration sensor (9) is communicatively connected with the vibration controller (8).

6. The fastener anti-loosening performance testing device according to claim 5, characterized in that: The acceleration sensor (9) is arranged at one end of the attachment plate (2) away from the test fixture (1).

7. The fastener anti-loosening performance testing device according to claim 5, characterized in that: At least half of the attachment plate (2) along its length direction protrudes from an end of the test fixture (1) away from the vibration platform (3).

8. The fastener anti-loosening performance testing device according to any one of claims 1 to 3, characterized in that: It also includes a data acquisition device (10) which is communicatively connected to the force sensor (4).

9. The fastener anti-loosening performance testing device according to claim 1, characterized in that: The attached plate (2) is a rigid plate.

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