Threaded connection looseness testing device

Abstract

The utility model relates to the technical field of threaded connection looseness testing, and provides a threaded connection looseness testing device, a movable piece is connected with a workbench through a stud and a nut, a gap is arranged between the stud and the movable piece, and the nut is tightly attached to the movable piece; an insulating part is clamped between the monitoring assembly and the movable part, the monitoring assembly comprises a first substrate and a second substrate, the first substrate is fixed to the movable part, a first electrode layer is laid on the first substrate, the second substrate is fixed to the nut, and a second electrode layer and a negative friction layer are laid on the second substrate in sequence. The negative friction layer is arranged between the first electrode layer and the second electrode layer, and when the nut rotates relative to the movable part, the negative friction layer and the first electrode layer generate relative displacement to generate an electric signal; and a plurality of rolling bodies are clamped between the movable part and the workbench. The monitoring assembly based on the friction nanometer generator principle is adopted, the sensitivity of the monitoring assembly for obtaining rotation of the nut relative to the stud is improved, and the measurement result is more accurate. And the self structure and the assembly are relatively simple.

Description

Technical Field

[0001] The utility model relates to the technical field of threaded connection looseness testing, in particular to a threaded connection looseness testing device. Background Art

[0002] Thread loosening is a common fastening failure. Experimental testing is one of the important means to study the mechanism of thread loosening. The main testing methods currently include detection methods using strain gauges, detection methods based on vibration analysis, detection methods based on piezoelectric active sensing, and detection methods based on ultrasonic flaw detection. Some of these methods have complex experimental systems, and some need to obtain thread loosening information by indirectly analyzing the response of the system, which affects the accuracy and timeliness of the test results.

[0003] Therefore, there is an urgent need for a threaded connection looseness testing device to solve the above technical problems. Utility Model Content

[0004] The utility model aims to provide a threaded connection looseness testing device, which has a relatively simple mechanical structure, can simplify the assembly process of the testing device and the nut to be tested, and has high monitoring accuracy.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] Threaded connection loosening test device, including:

[0007] Workbench;

[0008] A movable part, wherein the movable part is connected to the workbench through a stud and a nut, wherein one axial end of the stud is fixed to the workbench, and the other axial end thereof passes through the movable part and is threadedly connected to the nut, a gap is provided between the stud and the movable part, and the nut is in close contact with the movable part;

[0009] A monitoring component, wherein an insulating component is sandwiched between the monitoring component and the movable part, the monitoring component comprises a first substrate and a second substrate, the first substrate is fixed to the movable part, the first substrate is provided with a first electrode layer, the second substrate is fixed to the nut, the second substrate is provided with a second electrode layer and a negative friction layer in sequence, the negative friction layer is between the first electrode layer and the second electrode layer, and when the nut rotates relative to the movable part, the negative friction layer and the first electrode layer can be relatively displaced to generate an electrical signal;

[0010] A plurality of rolling bodies are sandwiched between the movable part and the workbench.

[0011] As a preferred technical solution of the above-mentioned threaded connection looseness testing device, the above-mentioned rolling element is integrally formed with the above-mentioned movable part or the above-mentioned workbench.

[0012] As a preferred technical solution of the above-mentioned threaded connection looseness testing device, the above-mentioned workbench and / or the movable part is provided with a groove, and the above-mentioned rolling body is movably arranged in the above-mentioned groove.

[0013] As a preferred technical solution of the above-mentioned threaded connection looseness testing device, the above-mentioned movable part can move along the first direction relative to the above-mentioned workbench, the multiple above-mentioned grooves are arranged in parallel, and the length direction of the above-mentioned grooves is parallel to the above-mentioned first direction, and the above-mentioned first direction is perpendicular to the axial direction of the above-mentioned stud.

[0014] As a preferred technical solution of the above-mentioned threaded connection loosening test device, the surface of the above-mentioned rolling element is coated with lubricating grease.

[0015] As a preferred technical solution of the above-mentioned threaded connection loosening test device, it also includes a driving component, the above-mentioned driving component includes an exciter and a force-applying member, the above-mentioned exciter is connected to the above-mentioned movable member through the above-mentioned force-applying member, and is used to apply a cyclic load to the above-mentioned movable member.

[0016] As a preferred technical solution of the above-mentioned threaded connection loosening testing device, the first surface of the above-mentioned negative friction layer and / or the second surface of the above-mentioned first electrode layer are distributed with nanoscale microstructures, and the first surface of the above-mentioned negative friction layer and the second surface of the above-mentioned first electrode layer can contact each other.

[0017] As a preferred technical solution of the above-mentioned threaded connection loosening test device, the above-mentioned microstructure is selected from nanowires, nanotubes, nanogrooves, nanocones and nanospheres.

[0018] As a preferred technical solution of the above-mentioned threaded connection looseness testing device, the above-mentioned second substrate and the above-mentioned insulating member are arranged at an axial spacing from the above-mentioned stud.

[0019] As a preferred technical solution of the above-mentioned threaded connection loosening test device, the above-mentioned first substrate and the above-mentioned second substrate are made of insulating materials.

[0020] Beneficial effects of the utility model:

[0021] The utility model provides a threaded connection loosening test device. In the preparation stage of the test, a movable part is connected to a workbench, a light hole is opened in the movable part, a stud is inserted into the light hole and is threadedly connected with a nut, a gap exists between the outer peripheral wall of the stud and the inner peripheral wall of the light hole, so that the movable part can move relative to the stud, the nut squeezes the movable part to one side of the workbench, and the nut is close to the surface of the movable part. An insulating part is arranged between the monitoring component and the movable part, which is used to prevent the current generated by the monitoring component from escaping to the movable part; the first substrate and the second substrate in the monitoring component are used as supporting parts to install the first electrode layer, the second electrode layer and the negative friction layer respectively, the first substrate is relatively fixed to the movable part, and the second substrate is fixed to the nut, when the monitoring component is in the first state, the first substrate and the second substrate are parallel and close to each other, at this time, the first electrode layer, the negative friction layer and the second electrode layer are close to each other in sequence; when the test starts, a force is applied to the movable part so that the movable part moves relative to the stud, and in this process, the movable part continuously applies a force to the nut until the nut rotates relative to the stud, the second substrate rotates with the nut, the second substrate and the first substrate are away from each other, and are arranged at an angle to generate an electrical signal. In this way, the monitoring component using the principle of friction nanogenerator can improve the sensitivity of the monitoring component to obtain the rotation of the nut relative to the stud, making the measurement result more accurate. And its own structure and assembly are relatively simple. By setting a rolling body between the movable part and the workbench, rolling friction is formed between the two, thereby reducing the friction coefficient between the two, reducing the work done to overcome the friction between the movable part and the workbench, on the one hand, it can reduce the output power used to drive the movable part to move; on the other hand, when the movable part moves relative to the workbench, the rolling body makes it easier for the movable part to move relative to the workbench, thereby improving the sensitivity of the movable part, and the force of the movable part is more easily transmitted to the nut. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0023] Figure 1 It is a structural schematic diagram of a threaded connection loosening test device provided by an embodiment of the utility model;

[0024] Figure 2 It is a top view of the movable part and the monitoring assembly provided by the embodiment of the utility model;

[0025] Figure 3 It is a schematic diagram of the structure of the monitoring component provided by the embodiment of the utility model;

[0026] Figure 4 It is a structural schematic diagram of the movable parts provided by the embodiment of the utility model;

[0027] Figure 5 It is a structural schematic diagram of a threaded connection looseness testing device provided in other embodiments of the utility model.

[0028] In the figure:

[0029] X, first direction;

[0030] 10. Workbench;

[0031] 20. movable part; 21. groove;

[0032] 31. Stud; 32. Nut;

[0033] 40. Monitoring component; 41. First substrate; 42. Second substrate; 43. Insulator; 44. First electrode layer; 45. Second electrode layer; 46. Negative friction layer; 47. Wiring harness; 48. Data collector;

[0034] 50. Rolling element;

[0035] 60. driving assembly; 61. vibrator; 62. force applying member;

[0036] 71. Screw; 72. Gasket; 73. Base. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0038] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0040] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0041] like Figures 1 to 5 As shown, the utility model provides a threaded connection loosening test device, including a workbench 10, a movable part 20 and a monitoring assembly 40. The movable part 20 is connected to the workbench 10 through a stud 31 and a nut 32, one axial end of the stud 31 is fixed to the workbench 10, and the other axial end passes through the movable part 20 and is threadedly connected to the nut 32, a gap is provided between the stud 31 and the movable part 20, and the nut 32 is in close contact with the movable part 20; an insulating member 43 is sandwiched between the monitoring assembly 40 and the movable part 20, and the monitoring assembly 40 includes a first substrate 41 and a second substrate 42, the first substrate 41 is fixed to the movable part 20, the first substrate 41 is paved with a first electrode layer 44, the second substrate 42 is fixed to the nut 32, the second substrate 42 is sequentially paved with a second electrode layer 45 and a negative friction layer 46, the negative friction layer 46 is between the first electrode layer 44 and the second electrode layer 45, when the nut 32 rotates relative to the movable part 20, the negative friction layer 46 and the first electrode layer 44 can be relatively displaced to generate an electrical signal.

[0042] Specifically, in the preparation stage of the test, the movable part 20 is connected to the workbench 10, and a light hole is opened in the movable part 20. The stud 31 is inserted into the light hole and is threadedly connected with the nut 32. There is a gap between the outer wall of the stud 31 and the inner wall of the light hole, so that the movable part 20 can move relative to the stud 31. The nut 32 squeezes the movable part 20 toward one side of the workbench 10, and the nut 32 is close to the surface of the movable part 20. An insulating member 43 is provided between the monitoring component 40 and the movable part 20, for preventing the current generated by the monitoring component 40 from escaping to the movable part 20; the first substrate 41 and the second substrate 42 in the monitoring component 40 serve as supporting members, for installing the first electrode layer 44, the second electrode layer 45 and the negative friction layer 46 respectively, the first substrate 41 is relatively fixed to the movable part 20, and the second substrate 42 is fixed to the nut 32, when the monitoring component 40 is in the first state, the first substrate 41 and the second substrate 42 are parallel and tightly attached, at this time, the first electrode layer 44, the negative friction layer 46 and the second electrode layer 45 are tightly attached in sequence; when the test starts, a force is applied to the movable part 20 to make the movable part 20 move relative to the stud 31, during which the movable part 20 continuously applies a force to the nut 32 until the nut 32 rotates relative to the stud 31, the second substrate 42 rotates with the nut 32, the second substrate 42 and the first substrate 41 move away from each other and are arranged at an angle to generate an electrical signal. In this way, the monitoring component 40 using the principle of the friction nanogenerator can improve the sensitivity of the monitoring component 40 in obtaining the rotation of the nut 32 relative to the stud 31, making the measurement result more accurate. And its own structure and assembly are relatively simple.

[0043] Furthermore, a plurality of rolling bodies 50 are sandwiched between the movable part 20 and the workbench 10. By arranging the rolling bodies 50 between the movable part 20 and the workbench 10, rolling friction is formed between the two, thereby reducing the friction coefficient between the two, and reducing the work done to overcome the friction between the movable part 20 and the workbench 10. On the one hand, the output power used to drive the movable part 20 to move can be reduced; on the other hand, when the movable part 20 moves relative to the workbench 10, the rolling bodies 50 make it easier for the movable part 20 to move relative to the workbench 10, thereby improving the sensitivity of the movable part 20, and the force of the movable part 20 is more easily transmitted to the nut 32.

[0044] Specifically, the second substrate 42 is bonded to the side of the nut 32 .

[0045] Further, it is assumed that when the nut 32 rotates clockwise, the nut 32 is tightened with the stud 31, and the nut 32 presses the movable part 20 toward one side of the workbench 10. When the nut 32 rotates counterclockwise, the nut 32 and the stud 31 are loosened, and the nut 32 moves away from the movable part 20 toward the side away from the workbench 10. When the nut 32 rotates counterclockwise, the nut 32 can drive the second substrate 42 to rotate.

[0046] Furthermore, the magnitude of the electrical signal output by the monitoring component 40 is related to the relative separation displacement between the negative friction layer 46 and the first electrode layer 44, that is, the angle of the counterclockwise rotation of the nut 32. The larger the angle, the larger the measured electrical signal. Taking the open circuit voltage as an example, when the separation displacement of the first substrate 41 and the second substrate 42 is much smaller than the size of the negative friction layer 46, the relationship between the open circuit voltage and the separation displacement is shown as follows:

[0047]

[0048] Where V OC is the open circuit voltage, x(t) is the separation displacement between the first electrode layer 45 and the negative friction layer 46, ε 0 is the relative dielectric constant of air, and σ is the uniformly distributed charge density on the friction layer.

[0049] Optionally, the workbench 10 and the base 73 are fixed by screws 71. The base 73 has a relatively large mass or is directly fixed to the ground. The workbench 10 maintains its relative fixation with the ground by virtue of the fixation with the base 73. In this way, when the driving movable part 20 is relatively shaken relative to the workbench 10, the displacement range between the movable part 20 and the workbench 10 is the largest, and the effect on the nut 32 is the best.

[0050] Optionally, the monitoring component 40 also includes a data collector 48 and two wiring harnesses 47, wherein one wiring harness 47 connects the first electrode layer 44 and the data collector 48, and the other wiring harness 47 connects the second electrode layer 45 and the data collector 48. The generated electrical signal is transmitted to the data collector 48 through the wiring harness 47. The data collector 48 can convert the electrical signal into a corresponding signal to indicate the degree of looseness of the nut 32 and the stud 31.

[0051] In other embodiments, the stud 31 and the workbench 10 are integrally formed.

[0052] Specifically, the first substrate 41 and the second substrate 42 are made of insulating materials; the first electrode layer 44 and the second electrode layer 45 can be made of aluminum, copper or other metal materials with good conductivity; the negative friction layer 46 can be made of readily available electronic materials such as polytetrafluoroethylene, polydimethylsiloxane, polyimide, polyethylene terephthalate, etc., and can be made of one of these materials, or two, three or four of them.

[0053] Optionally, the workbench 10 and / or the movable part 20 are provided with a groove 21, and the rolling body 50 is movably arranged in the groove 21. In this way, the groove 21 is used to limit the moving direction of the rolling body 50, so that the rolling body 50 is always located between the workbench 10 and the movable part 20, so as to prevent the rolling body 50 from leaving the coverage area of ​​the movable part 20 when the movable part 20 moves relative to the workbench 10.

[0054] In other embodiments, the rolling element 50 is integrally formed with the movable member 20 or the workbench 10 .

[0055] In other embodiments, the second surface of the movable member 20 is wavy, the first surface of the workbench 10 is flat, and the second surface of the movable member 20 is in contact with the first surface of the workbench 10 .

[0056] Optionally, the movable member 20 can move relative to the workbench 10 along the first direction X, and the plurality of grooves 21 are arranged in parallel, and the length direction of the grooves 21 is parallel to the first direction X, and the first direction X is perpendicular to the axial direction of the stud 31. Specifically, a plurality of rolling bodies 50 are sequentially placed in each groove 21.

[0057] like Figure 4 As shown, in this embodiment, the grooves 21 are all opened on the surface of the movable member 20, and the stud 31 passes through between two grooves 21 located at the central position.

[0058] Optionally, lubricating grease is applied to the surface of the rolling body 50. Thus, by applying lubricating grease, the friction between the rolling body 50 and the movable plate can be further reduced.

[0059] Optionally, the threaded connection loosening test device further includes a driving assembly 60 , wherein the driving assembly 60 includes a vibration exciter 61 and a force applying member 62 , and the vibration exciter 61 is connected to the movable member 20 via the force applying member 62 for applying a cyclic load to the movable member 20 .

[0060] Specifically, the exciter 61 is a device attached to certain machines and equipment to generate an excitation force, which can make the excited object obtain a certain form and magnitude of vibration, so as to perform vibration and strength tests on the object, or calibrate the vibration test instrument and sensor. In this embodiment, the force generated by the exciter 61 is transmitted to the movable member 20 through the force applying member 62, so that the movable member 20 can move the object workbench 10.

[0061] Furthermore, the exciter 61 applies a cyclic load to the movable part 20 through the force-applying member 62 , and by adjusting the cyclic load amplitude and frequency output by the exciter 61 , a loosening experimental test of the stud 31 under different cyclic load amplitudes and frequencies can be performed.

[0062] It should be noted that the vibration exciter 61 and the force applying member 62 are actually existing technologies, and their specific mechanical structures, connection relationships and transmission principles are not described here in detail.

[0063] In other embodiments, the vibrator 61 is fixedly mounted on the movable member 20 .

[0064] Optionally, the first surface of the negative friction layer 46 and / or the second surface of the first electrode layer 44 are distributed with nanoscale microstructures, and the first surface of the negative friction layer 46 and the second surface of the first electrode layer 44 can contact each other. By physically modifying the first surface of the negative friction layer 46 and / or the second surface of the first electrode layer 44, a nanoscale microstructure array is distributed on the surface thereof, so as to increase the contact area between the negative friction layer 46 and the first electrode layer 44, thereby increasing the contact charge amount. Specific modification methods include photolithography, chemical etching, plasma etching, etc.

[0065] Optionally, the microstructure is selected from nanowires, nanotubes, nanotrench, nanocones and nanospheres.

[0066] Optionally, the second substrate 42 and the insulating member 43 are spaced apart in the axial direction of the stud 31. When the second substrate 42 rotates with the nut 32, no friction occurs between the bottom of the second substrate 42 and the insulating member 43, so that the second substrate 42 is more sensitive to the rotation of the nut 32 relative to the stud 31, and can more accurately rotate synchronously with the nut 32.

[0067] like Figure 5 As shown, in other embodiments, the workbench 10 is in a U-shape, the movable part 20 is installed on the outside of the workbench 10, the nut 32 and the monitoring component 40 are installed in the workbench 10, and the driving component 60 applies a force to the movable part 20 on the outside of the workbench 10, so that the movable part 20 is displaced relative to the stud 31 along the axial direction of the stud 31.

[0068] In other embodiments, the first substrate 41 and the second substrate 42 of the monitoring component 40 always remain parallel, the first substrate 41 is relatively fixed to the movable part 20, and the second substrate 42 slides relative to the first substrate 41. When in the ready state, one end of the first substrate 41 and the second substrate 42 are both in contact with the same side of the nut 32; during the test, when the nut 32 rotates relative to the stud 31, the side of the nut 32 tilts, and the first substrate 41 and the second side plate slide relative to each other. At this time, the friction between the first electrode layer 44 and the negative friction layer 46 generates an electrical signal.

[0069] In addition, the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. Threaded connection loosening test device, characterized in that: include: Workbench (10); A movable part (20), wherein the movable part (20) is connected to the workbench (10) via a stud (31) and a nut (32), wherein one axial end of the stud (31) is fixed to the workbench (10), and the other axial end thereof passes through the movable part (20) and is threadedly connected to the nut (32), a gap is provided between the stud (31) and the movable part (20), and the nut (32) is in close contact with the movable part (20); A monitoring component (40), wherein an insulating component (43) is sandwiched between the monitoring component (40) and the movable part (20), and the monitoring component (40) comprises a first substrate (41) and a second substrate (42), wherein the first substrate (41) is fixed to the movable part (20), and the first substrate (41) is provided with a first electrode layer (44), and the second substrate (42) is fixed to the nut (32), and the second substrate (42) is provided with a second electrode layer (45) and a negative friction layer (46) in sequence, wherein the negative friction layer (46) is located between the first electrode layer (44) and the second electrode layer (45), and when the nut (32) rotates relative to the movable part (20), the negative friction layer (46) and the first electrode layer (44) can be relatively displaced to generate an electrical signal; A plurality of rolling bodies (50) are sandwiched between the movable member (20) and the workbench (10).

2. The threaded connection loosening test device according to claim 1, characterized in that: The rolling body (50) is integrally formed with the movable part (20) or the workbench (10).

3. The threaded connection loosening test device according to claim 1, characterized in that: The workbench (10) and / or the movable part (20) is provided with a groove (21), and the rolling body (50) is movably arranged in the groove (21).

4. The threaded connection loosening test device according to claim 3, characterized in that: The movable part (20) is movable relative to the workbench (10) along a first direction (X), a plurality of grooves (21) are arranged in parallel, and the length direction of the grooves (21) is parallel to the first direction (X), and the first direction (X) is perpendicular to the axial direction of the stud (31).

5. The threaded connection loosening test device according to claim 2, characterized in that: The surface of the rolling element (50) is coated with lubricating grease.

6. The threaded connection loosening test device according to claim 1, characterized in that: It also includes a driving assembly (60), wherein the driving assembly (60) includes a vibration exciter (61) and a force applying member (62), wherein the vibration exciter (61) is connected to the movable member (20) via the force applying member (62) and is used to apply a cyclic load to the movable member (20).

7. The threaded connection loosening test device according to claim 1, characterized in that: The first surface of the negative friction layer (46) and / or the second surface of the first electrode layer (44) are distributed with nanoscale microstructures, and the first surface of the negative friction layer (46) and the second surface of the first electrode layer (44) are capable of contacting each other.

8. The threaded connection loosening test device according to claim 7, characterized in that: The microstructure is selected from the group consisting of nanowires, nanotubes, nanogrooves, nanocones and nanospheres.

9. The threaded connection loosening test device according to claim 1, characterized in that: The second substrate (42) and the insulating member (43) are arranged at intervals in the axial direction of the stud (31).

10. The threaded connection loosening test device according to claim 1, characterized in that: The first substrate (41) and the second substrate (42) are made of insulating materials.

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