Friction coefficient measuring device

Abstract

The utility model provides a friction coefficient measuring device. The friction coefficient measuring device comprises a shell, a bearing structure, a load transmission structure, a rotating part and a rotating rod, a closed cavity is formed in the shell. The bearing structure is located in the cavity and provided with a bearing surface. The load transmission structure is located above the bearing surface; the end, facing the bearing surface, of the load transmission structure is located in the cavity, and the load bearing end, away from the bearing surface, of the load transmission structure is exposed out of the shell. The rotating part is located in the cavity and located between the bearing surface and the load transmission structure, the rotating part makes contact with the bearing surface and the surface, facing the bearing surface, of the load transmission structure, and the rotating part, the bearing structure and the part, making contact with the rotating part, of the load transmission structure are made of the same material. The end part, far away from the rotating part, of the rotating rod is exposed out of the shell; the rotating rod can rotate relative to the shell so as to drive the rotating part to rotate between the bearing surface and the load transmission structure.

Description

Technical Field

[0001] This application relates to the technical field of measuring the coefficient of friction, and particularly to a device for measuring the coefficient of friction. Background Art

[0002] As a fourth-generation reactor, the research and development of high-temperature gas-cooled reactors have attracted much attention globally. Graphite, as the structural material and moderator of spherical fuel elements in high-temperature gas-cooled reactors, its properties, especially the coefficient of friction of graphite, are crucial for the design, operation, and maintenance of high-temperature gas-cooled reactors and are one of the key research points. Therefore, measuring the frictional force of graphite is of great significance for the design, operation, and maintenance of high-temperature gas-cooled reactors. Utility Model Content

[0003] An embodiment of this application provides a device for measuring the coefficient of friction. The device for measuring the coefficient of friction includes:

[0004] A housing; a sealed cavity is provided inside the housing;

[0005] A bearing structure, located inside the cavity, having a bearing surface;

[0006] A load transfer structure, located above the bearing surface; the end of the load transfer structure facing the bearing surface is located inside the cavity, and the load-bearing end of the load transfer structure away from the bearing surface exposes out of the housing;

[0007] A rotating part, located inside the cavity and between the bearing surface and the load transfer structure, the rotating part is in contact with the bearing surface and the surface of the load transfer structure facing the bearing surface respectively; the materials of the rotating part, the bearing structure, and the part of the load transfer structure in contact with the rotating part are the same;

[0008] A rotating rod, connected to the rotating part, and the end away from the rotating part exposes out of the housing; the rotating rod can rotate relative to the housing to drive the rotating part to rotate between the bearing surface and the load transfer structure.

[0009] In one embodiment, the load transfer structure includes a connecting rod and a pressing plate connected to the end of the connecting rod facing the bearing surface, and the orthographic projection of the pressing plate on the plane where the bearing surface is located covers the orthographic projection of the rotating part on the plane.

[0010] In one embodiment, the shape of the rotating part is spherical.

[0011] In one embodiment, the device for measuring the coefficient of friction further includes a positioning part, the positioning part is located between the bearing surface and the load transfer structure, and abuts against the side surface of the rotating part away from the rotating rod.

[0012] In one embodiment, the measuring device for the coefficient of friction further includes a heating element located in the cavity, and the heating element is disposed on at least opposite sides of the bearing structure.

[0013] In one embodiment, the measuring device for the coefficient of friction further includes a heat insulation structure located in the housing, and the cavity is disposed within the heat insulation structure.

[0014] In one embodiment, the measuring device for the coefficient of friction further includes a heat insulating material filled between the heat insulation structure and the housing.

[0015] In one embodiment, the bearing structure is provided with an accommodation space. The bearing structure includes a bearing plate and first and second side plates located on opposite sides of the accommodation space. The first and second side plates are respectively connected to the bearing plate. The rotating part is located within the accommodation space, and the surface of the bearing plate facing the load transfer structure is a bearing surface;

[0016] The measuring device for the coefficient of friction further includes a plurality of positioning rods for positioning the bearing structure within the housing. The first and second side plates are respectively connected to the plurality of positioning rods. Among the plurality of positioning rods connected to the first side plate, at least two of the positioning rods have different distances to the load bearing end, and at least two positioning rods are located on opposite sides of the accommodation space; and / or, among the plurality of positioning rods connected to the second side plate, at least two of the positioning rods have different distances to the load bearing end, and at least two positioning rods are located on opposite sides of the accommodation space.

[0017] In one embodiment, the measuring device for the coefficient of friction further includes a seal. Seals are respectively provided at the positions where the load transfer structure exposes the housing and where the rotating part exposes the housing.

[0018] In one embodiment, the housing is further provided with a coolant channel for the circulation of coolant to cool down the seal.

[0019] For the measuring device for the coefficient of friction provided by the embodiments of the present application, since the materials of the rotating part, the bearing structure, and the part of the load transfer structure in contact with the rotating part are the same, the coefficient of friction of the material of the rotating part can be measured by using the measuring device; the part of the rotating rod exposed from the housing can be connected to a driving device, and the driving device drives the rotating part to rotate through the rotating rod. According to the torque output by the driving device to the rotating rod and the magnitude of the load applied to the load bearing end of the load transfer structure, the coefficient of friction of the material of the rotating part can be calculated; by providing a sealed cavity within the housing, the temperature and air pressure within the cavity can be adjusted, and thus the coefficient of friction of the material of the rotating part under different working conditions can be measured, and the application of the measuring device is more flexible and extensive. Brief Description of the Drawings

[0020] Figure 1 is a cross-sectional view of a measuring device provided by an exemplary embodiment of the present application;

[0021] Figure 2 is a perspective view of a partial structure of a measuring device provided by an exemplary embodiment of the present application;

[0022] Figure 3 is Figure 2 a schematic view obtained by cutting the structure shown along AA;

[0023] Figure 4 is a schematic view of the structure of a rotating part and a rotating rod provided by an exemplary embodiment of the present application;

[0024] Figure 5 is a perspective view of a partial structure of a measuring device provided by an exemplary embodiment of the present application;

[0025] Figure 6 is Figure 5 a top view of the structure shown;

[0026] Figure 7 is a perspective view of a partial structure of a measuring device provided by an exemplary embodiment of the present application;

[0027] Figure 8 is a schematic view of an electrode, a conductive connection part, and a conductive connection structure provided by an exemplary embodiment of the present application;

[0028] Figure 9 is a schematic view of a heating element and a suspension beam provided by an exemplary embodiment of the present application;

[0029] Figure 10 is a flowchart of a method for measuring the coefficient of friction provided by an exemplary embodiment of the present application;

[0030] Figure 11 is a schematic diagram of the force analysis of a rotating part and a rotating rod provided by an exemplary embodiment of the present application. Specific Embodiments

[0031] Here, the technical solutions in the embodiments (or "embodiment modes") of the present application will be clearly and completely described in conjunction with the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other. When the following description relates to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0032] If there are terms related to directional indication or positional relationship in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture (as shown in the accompanying drawings); if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. involved in the embodiments of the present application are only for the purpose of convenient description and should not be construed as indicating or implying relative importance.

[0033] The embodiments of the present application provide a device for measuring the coefficient of friction. As Figures 1 to 3 shown, the device for measuring the coefficient of friction includes a housing 10, a bearing structure 20, a load transfer structure 30, a rotating part 40, and a rotating rod 50. A sealed cavity 101 is provided inside the housing 10. The bearing structure 20 is located in the cavity 101, and the bearing structure 20 is provided with a bearing surface 201. The load transfer structure 30 is located above the bearing surface 201; the end of the load transfer structure 30 facing the bearing surface 201 is located in the cavity 101, and the load-bearing end 301 of the load transfer structure 30 away from the bearing surface 201 exposes the housing 10. The rotating part 40 is located in the cavity 101 and between the bearing surface 201 and the load transfer structure 30, and the rotating part 40 is in contact with the bearing surface 201 and the surface of the load transfer structure 30 facing the bearing surface 201 respectively. The materials of the rotating part 40, the bearing structure 20, and the part of the load transfer structure 30 in contact with the rotating part 40 are the same. The rotating rod 50 is connected to the rotating part 40, and the end away from the rotating part 40 exposes the housing 10; the rotating rod 50 can rotate relative to the housing 10 to drive the rotating part 40 to rotate between the bearing surface 201 and the load transfer structure 30.

[0034] The friction coefficient measuring device provided in the embodiment of the present application is a device for measuring the friction coefficient of the material of the rotating part 40, because the materials of the rotating part 40, the bearing structure 20 and the parts of the load transfer structure 30 that are in contact with the rotating part 40 are the same. Therefore, the friction coefficient of the material of the rotating part 40 can be measured by using the measuring device. The part of the rotating rod 50 exposed from the shell can be connected to the driving device, and the driving device drives the rotating part 40 to rotate through the rotating rod 50. The friction coefficient of the material of the rotating part 40 can be calculated according to the torque output by the driving device to the rotating rod 50 and the load applied to the load-bearing end 301 of the load transfer structure 30. By providing a closed cavity 101 in the shell 10, the temperature and air pressure in the cavity 101 can be adjusted, so that the friction coefficient of the material of the rotating part 40 under different working conditions can be measured, and the application of the measuring device is more flexible and extensive.

[0035] It should be noted that Figure 1 The corresponding three-dimensional structure cut position and Figure 2 The incision position is the same.

[0036] In the embodiment of the present application, a closed cavity means that the cavity is not absolutely closed and there may be a location where gas leaks in the cavity, but the rate of gas leakage is very small and has little effect on the change of gas pressure in the cavity.

[0037] In one embodiment, Figure 1 and Figure 3 As shown, the load transfer structure 30 includes a connecting rod 31 and a pressing plate 32 connected to the end of the connecting rod 31 facing the bearing surface 201, and the orthographic projection of the pressing plate 32 on the plane where the bearing surface 201 is located covers the orthographic projection of the rotating part 40 on the plane. The surface of the connecting rod 31 away from the pressing plate 32 is the load bearing end 301. Such a configuration can ensure that the rotating part 40 is in full contact with the pressing plate 32, and the pressing plate 32 can effectively transfer the load received by the load bearing end 301 to the rotating part 40, which can avoid the relative position of the rotating part 40 and the load transfer structure 30 changing during the assembly process of the measuring device, resulting in the load received by the load bearing end 301 not being effectively transferred to the rotating part 40, thereby affecting the measurement of the friction coefficient. The connecting rod 31 passes through the housing 10, and it is not fixedly connected to the housing 10. The load received by the load bearing end 301 can be transferred to the pressing plate 32 through the connecting rod 31, and then the pressing plate 32 is transferred to the rotating part 40.

[0038] In one embodiment, the pressing plate 32 may be provided with a mounting groove, and the end of the connecting rod 31 is inserted into the mounting groove of the pressing plate 32 and fixedly connected to the pressing plate 32 .

[0039] In one embodiment, Figure 3As shown, the bearing structure 20 is provided with an accommodation space 202, and both the rotating part 40 and the pressing plate 32 are located in the accommodation space 202. The rotating rod 50 drives the rotating part 40 to rotate in the accommodation space 202.

[0040] In one embodiment, as Figure 2 and Figure 3 shown, the bearing structure 20 includes bearing plates 21 and a top plate 24 located on opposite sides of the accommodation space 202, and a first side plate 22 and a second side plate 23 located on opposite sides of the accommodation space 202. The first side plate 22 and the second side plate 23 are respectively connected to the bearing plate 21 and the top plate 24. The surface of the bearing plate 21 facing the load transfer structure 30 is the bearing surface 201. The surface of the pressing plate 32 away from the bearing surface 201 abuts against the top plate 24. The connecting rod 31 passes through the top plate 24.

[0041] In one embodiment, as Figure 1 and Figure 3 shown, the rotating part 40 is spherical in shape. By setting the rotating part 40 to be spherical, the rotation of the rotating part 40 is relatively smooth, and it is easier for the driving device to control the rotation of the rotating part 40; and the space occupied by the rotating part 40 is smaller, and the cavity 101 can be set smaller, which helps to save the manufacturing cost. In other embodiments, the rotating part 40 may also be cylindrical in shape.

[0042] In one embodiment, as Figure 4 shown, the rotating part 40 is provided with an opening 41, and the rotating rod 50 is inserted into the opening 41 and fixedly connected to the rotating part 40.

[0043] In one embodiment, as Figures 1 to 3 shown, the friction coefficient measuring device further includes a plurality of positioning rods 71 for positioning the bearing structure 20 in the housing 10. The first side plate 22 and the second side plate 23 are respectively connected to the plurality of positioning rods 71. By providing the positioning rods 71, the bearing structure 20 can be positioned to prevent the bearing structure 20 from moving relative to the housing 10 and affecting the movement of the rotating part 40, thereby affecting the accuracy of the friction coefficient.

[0044] In one embodiment, as Figures 1 to 3 shown, the first side plate 22 and the second side plate 23 are respectively provided with grooves, and one end of the positioning rod 71 is inserted into the corresponding groove of the bearing structure 20. The end of the positioning rod 71 away from the bearing structure 20 is fixed relative to the housing 10.

[0045] In one embodiment, among the plurality of positioning rods 71 connected to the first side plate 22, the distances from at least two of the positioning rods 71 to the load bearing end 301 are different, and at least two positioning rods 71 are located on opposite sides of the accommodation space 202. With such an arrangement, the plurality of positioning rods 71 connected to the first side plate 22 can limit the movement of the first side plate 22 in the vertical and horizontal directions, and can improve the positioning effect of the bearing structure 20.

[0046] In one embodiment, among the plurality of positioning rods 71 connected to the second side plate 23, the distances from at least two of the positioning rods 71 to the load bearing end 301 are different, and at least two positioning rods 71 are located on opposite sides of the accommodation space 202. With such an arrangement, the plurality of positioning rods 71 connected to the second side plate 23 can limit the movement of the second side plate 23 in the vertical and horizontal directions, and can improve the positioning effect of the bearing structure 20.

[0047] Preferably, the first side plate 22 and the second side plate 23 are respectively connected to a plurality of positioning rods 71. With such an arrangement, the positioning effect on the bearing structure 20 is better.

[0048] In one embodiment, as Figure 1 、 Figure 5 and Figure 6 shown, the housing 10 is provided with a plurality of extension parts 13. The extension parts 13 can correspond to the positioning rods 71 one by one. Each positioning rod 71 passes through the corresponding extension part 13, and the end part exposes from the extension part 13; the measuring device further includes a plurality of fixed end caps 91. Each fixed end cap 91 is connected to an extension part 13 and abuts against the end part of the positioning rod 71 that exposes from the extension part 13. In this way, the positioning rod 71 positions the bearing structure 20 in the housing 10. In some embodiments, the fixed end cap 91 and the extension part 13 can be threadedly connected.

[0049] In one embodiment, as Figures 1 to 3 shown, the measuring device further includes a plurality of top fixing rods 72 and a plurality of bottom fixing rods 74. The top fixing rods 72 are used to position the top of the bearing structure 20, and the bottom fixing rods 74 are used to position the bottom of the bearing structure 20. In this way, the stability of the bearing structure 20 in the cavity 101 can be further improved.

[0050] In one embodiment, Figure 5 and Figure 7As shown, a plurality of extension parts 12 are provided at the top of the housing 10, and a plurality of extension parts 16 are provided at the bottom. The measuring device further includes a plurality of fixed end caps 94 and a plurality of fixed end caps 95. The top fixing rods 72 correspond to the extension parts 12 one by one, and each top fixing rod 72 passes through the corresponding extension part 12; each extension part 12 is connected to a fixed end cap 94, one end of the top fixing rod 72 abuts against the bearing structure 20, and the other end exposes the corresponding extension part 12 and abuts against the fixed end cap 94. The bottom fixing rods 74 correspond to the extension parts 16 one by one, and each bottom fixing rod 74 passes through the corresponding extension part 16; each extension part 16 is connected to a fixed end cap 95, one end of the bottom fixing rod 74 abuts against the bearing structure 20, and the other end exposes the corresponding extension part 16 and abuts against the fixed end cap 95. In some embodiments, the fixed end cap 94 and the extension part 12 can be threadedly connected, and the fixed end cap 95 and the extension part 16 can be threadedly connected.

[0051] In one embodiment, as Figure 1 and Figure 3 shown, the friction coefficient measuring device further includes a positioning part 61. The positioning part 61 is located between the bearing surface 201 and the load transfer structure 30, and abuts against the side surface of the rotating part 40 away from the rotating rod 50. With such a setting, the positioning part 61 limits the movement of the rotating part 40 in the extending direction of the rotating rod 50, which can improve the stability of the rotation of the rotating part 40 in the cavity 101, avoid moving in other directions except the rotation direction, and contribute to improving the accuracy of the friction coefficient measurement.

[0052] In one embodiment, as Figure 1 and Figure 3 shown, the measuring device further includes a positioning rod 73. The positioning rod 73 is connected to the housing 10 and is connected to the end of the positioning part 61 away from the rotating part 40. The positioning rod 73 restricts the movement of the positioning part 61 in the extending direction of the rotating rod 50, and further restricts the movement of the rotating part 40 in this direction.

[0053] In one embodiment, as Figure 1 , Figure 5 and Figure 6 shown, the housing 10 is provided with a hollow extension part 15. The positioning rod 73 passes through the extension part 15, and the end exposes the extension part 15; the measuring device further includes a fixed end cap 93. The fixed end cap 93 is connected to the extension part 15 and abuts against the end of the positioning rod 73 exposed from the extension part 15. In this way, the positioning rod 73 is fixed, and thus the positioning part 61 is fixed. In some embodiments, the fixed end cap 93 and the extension part 15 can be threadedly connected.

[0054] In one embodiment, as Figure 3As shown, the surface of the positioning portion 61 facing the pressing plate 32 abuts against the pressing plate 32, and the surface of the positioning portion 61 away from the pressing plate abuts against the bearing surface 201. The side surface of the positioning portion 61 facing the first side plate 22 abuts against the first side plate 22, and the side surface of the positioning portion 61 facing the second side plate 23 abuts against the second side plate 23. In this way, the movement of the positioning portion 61 in the vertical direction and the horizontal direction is restricted, and the influence of the movement of the positioning portion 61 in the vertical direction and the horizontal direction on the rotating portion 40 can be prevented.

[0055] In one embodiment, as Figure 1 and Figure 5 shown, the housing 10 is provided with a hollow extension portion 14, the rotating rod 50 passes through the extension portion 14, and the end portion exposes the extension portion 14; the measuring device further includes a fixed end cap 92, the fixed end cap 92 is connected to the extension portion 14 and abuts against the portion of the rotating rod 50 that exposes the extension portion 14. In this way, the rotating rod 50 cannot move relative to the housing 10 in its extending direction, and the influence of the movement of the rotating rod 50 in its extending direction on the friction coefficient measurement can be avoided.

[0056] In one embodiment, as Figure 5 shown, the rotating rod 50 includes a connecting member 51, and the connecting member 15 exposes the fixed end cap 92 through the through hole of the fixed end cap 92. The connecting member 51 can be used to connect to a driving device. The connecting member 51 can be a coupler.

[0057] In one embodiment, as Figure 7 shown, the friction coefficient measuring device further includes a heating element 62 located in the cavity 101, and the heating element 62 is disposed on at least opposite sides of the bearing structure 20. By providing the heating element 62 located in the cavity 101, it is convenient to adjust the temperature in the cavity 101; compared with the solution of disposing the heating element 62 outside the housing 10, disposing the heating element 62 in the cavity 101 can make the temperature rising speed in the cavity 101 faster, which is beneficial to shortening the measurement time; the heating element 62 is disposed on opposite sides of the bearing structure 20, so that the temperature distribution in the cavity 101 is more uniform.

[0058] In one embodiment, as Figure 8 shown, the measuring device further includes an electrode 81, a conductive connection portion 82 and a conductive connection structure 83. The conductive connection portion 82 is located inside the housing 10, and the electrode 81 is located outside the housing 10. Both ends of the conductive connection portion 82 are respectively connected to the electrode 81 and the conductive connection structure 83. The conductive connection structure 83 is electrically connected to the heating element 62, and the electrode 81 can be connected to an external power supply, so that the external power supply can supply power to the heating element 62 through the electrode 81, the conductive connection portion 82 and the conductive connection structure 83 in sequence.

[0059] In one embodiment, as Figure 8As shown, an installation groove 831 is provided on the side of the conductive connection structure 83. As Figure 9 shown, the measuring device further includes a cantilever 65 connected to the heating element 62, and the material of the cantilever 65 is a conductive material. As Figure 7 shown, the cantilever 65 is clamped in the installation groove 831 and is in direct contact with the conductive connection structure 83. In this way, the cantilever 65 can fix the heating element 62 and realize the electrical connection between the heating element 62 and the conductive connection structure 83. The measuring device housing includes two juxtaposed cantilevers 65, and installation grooves 831 can be respectively provided on the opposite sides of the conductive connection structure 83, and the two cantilevers 65 are respectively clamped in different installation grooves 831 of the conductive connection structure 83. The measuring device can be provided with two electrodes 81, one of which is the positive electrode and the other is the negative electrode.

[0060] In one embodiment, as Figure 1 shown, the friction coefficient measuring device further includes a heat insulation structure 63 located inside the housing, and the cavity 101 is arranged inside the heat insulation structure 63; the friction coefficient measuring device further includes a heat preservation material 64 filled between the heat insulation structure 63 and the housing 10. By providing the heat insulation structure 63 and the heat preservation material 64, the temperature in the cavity 101 can be effectively maintained constant, and the change of the temperature in the cavity 101 can be avoided from affecting the accuracy of the measured friction coefficient. The conductive connection part 82, the positioning rod 71, the top positioning rod 72, the positioning rod 73, the bottom positioning rod 74 and the rotating rod 50 respectively pass through the heat insulation structure 63 and the heat preservation material 64, and the heat insulation structure 63 and the heat preservation material 64 can also play a limiting role on the conductive connection part 82, the positioning rod 71, the top positioning rod 72, the positioning rod 73, the bottom positioning rod 74 and the rotating rod 50 to prevent them from tilting.

[0061] In one embodiment, the measuring device further includes a heat preservation cotton covering the housing 10 and a metal layer covering the heat preservation cotton. The material of the metal layer can be iron, for example. In this way, the heat dissipation rate of the measuring device can be further reduced, which helps to maintain the temperature in the cavity 101.

[0062] In one embodiment, the materials of the conductive connection part 82, the conductive connection structure 83, the positioning rod 71, the top positioning rod 72, the positioning rod 73, the bottom positioning rod 74 and the rotating rod 50 can all be graphite. In this way, these structures can withstand high temperatures and will not deform when the temperature in the cavity 101 is relatively high, without affecting the measurement of the friction coefficient.

[0063] In one embodiment, as Figure 5 and Figure 6 shown, the measuring device further includes an air valve 84 arranged outside the housing 10, and the air valve 84 is communicated with the cavity 101. The air valve 84 includes an intake valve and an exhaust valve, and is used to replace the gas in the cavity 101.

[0064] In one embodiment, the measuring device is further provided with a plurality of interfaces communicating with the cavity 101, and the interfaces are used to connect a temperature sensor and a pressure sensor to monitor the temperature and air pressure in the cavity 101.

[0065] In one embodiment, the friction coefficient measuring device further includes a seal. Seals are respectively provided at the positions where the rotating part 40 exposes the housing 10, the positions where the load transfer structure 30 exposes the housing 10, the positions where the positioning rods expose the housing 10, the positions where the conductive connection part 82 exposes the housing 10, the installation positions of the temperature sensor, the installation positions of the pressure sensor, and the installation position of the air valve 84. In this way, the sealing performance of the cavity 101 can be improved.

[0066] In one embodiment, the housing 10 can be formed by connecting a cover body 11 and a main body part 12, and a seal is provided at the connection between the cover body 11 and the main body part 12.

[0067] In one embodiment, the housing 10 is further provided with a coolant channel for the circulation of coolant to cool the seal. In this way, it can prevent the seal from failing due to too high a temperature. When the temperature in the cavity 101 is too high, water can be introduced into the coolant channel to cool the seal.

[0068] In one embodiment, the friction coefficient measuring device can be used to measure the friction coefficient of graphite, and the materials of the rotating part 40, the pressing plate 32 and the bearing structure 20 are all graphite.

[0069] The embodiment of the present application also provides a method for measuring the friction coefficient, which is applied to a measurement system including the friction coefficient measuring device described in any of the above embodiments. As Figure 10 shown, the method for measuring the friction coefficient includes the following steps 110 to step 140.

[0070] In step 110, the temperature in the cavity is adjusted to a set temperature, and the air pressure in the cavity is adjusted to a set air pressure.

[0071] In one embodiment, a gas cylinder is connected to the intake valve of the measuring device, and the exhaust valve of the measuring device is opened to replace the gas in the experimental device. To ensure that the gas in the experimental device is basically replaced, the exhaust time of a single exhaust valve is not less than 10 minutes, and the total exhaust time of all exhaust valves is not less than 30 minutes.

[0072] In one embodiment, the measuring device further includes a driving device, a heating power supply, a torque sensor, and a data acquisition system. The data acquisition system is electrically connected to the driving device, and the driving device is connected to the rotating rod to drive the rotating rod to rotate. The torque sensor can be disposed on the output shaft of the driving device for real-time detection of the output torque of the driving device. The data acquisition system can acquire the output torque detected by the torque sensor.

[0073] In one embodiment, before step 120, the measuring method further includes: controlling the heating power supply to supply power to the electrode, turning on the data acquisition system, and supplying coolant to the coolant channel of the measuring device.

[0074] In step 120, a load is applied to the load bearing end, the driving device connected to the rotating rod is controlled to output torque, and when the driving device drives the rotating part to rotate at a constant speed, the output torque of the driving device is determined.

[0075] In one embodiment, when the rotating part rotates at a constant speed, the output torque of the driving device may not be a constant value and may vary within a certain range. Then, the average value of the output torque within a period of time when the rotating part rotates at a constant speed can be taken as the output torque of the driving device.

[0076] In one embodiment, in step 120, after applying a load to the load bearing end, the driving device connected to the rotating rod is controlled to output torque, and when the driving device drives the rotating part to rotate at a constant speed, the step of determining the output torque of the driving device can be repeated multiple times, and the average value of the obtained multiple output torques is used as the output torque finally determined in step 120. In some embodiments, it can be repeated four times, twice clockwise and twice counterclockwise respectively.

[0077] In one embodiment, a load can be applied to the load bearing end by placing weights on the load bearing end.

[0078] In step 130, the load received by the load bearing end is changed at least once, and after each change of the load received by the load bearing end, the driving device connected to the rotating rod is controlled to output torque, and when the driving device drives the rotating part to rotate at a constant speed, the output torque of the driving device is determined.

[0079] In one embodiment, the load applied to the load bearing end can be changed by replacing the weight of the weights placed on the load bearing end.

[0080] In one embodiment, the rotation speed when the rotating part rotates at a constant speed in this step is the same as the speed when the rotating part rotates at a constant speed in step 120.

[0081] In one embodiment, in step 130, when the rotating part rotates at a constant speed, the output torque of the driving device may not be a constant value and may vary within a certain range. Then, the average value of the output torque within a period of time when the rotating part rotates at a constant speed can be taken as the output torque of the driving device.

[0082] In step 140, according to the magnitudes of the respective loads and the corresponding output torques, the dynamic friction coefficient of the material of the rotating part is calculated at the set temperature and the set air pressure.

[0083] As Figure 11 shown, the rotating part 40 is subjected to a downward load N, the frictional force F of the pressing plate 32 on the rotating part 40 f1 and the frictional force F of the bearing plate 21 of the bearing structure 20 on the rotating part 40 f2 , and the output torque provided by the driving device to the rotating rod 50 is T. The above parameters satisfy the following relational expressions (1) to (3):

[0084] T = (F f1 + F f2 )R + T r (1)

[0085] F f1 = μN (2)

[0086] F f1 = μ(N + G) (3)

[0087] wherein, R is the radius of rotation of the rotating part; G is the mass of the rotating part 40, μ is the dynamic friction coefficient of the material of the rotating part 40, and T r is the resistance torque of other structures of the device on the rotating part 40. When the temperature and air pressure in the cavity 101 are constant, T r is a constant value.

[0088] From the above relational expressions (1) to (3), the following relational expression (4) can be deduced:

[0089] T = (2N + G)μR + T r (4)

[0090] In one embodiment, when the temperature and pressure in the cavity are the set pressure and the set temperature respectively, two groups of data are measured. Each group of data includes the load received by the load bearing end and the corresponding output torque. The two groups of data are respectively: the load received by the load bearing end is N1, and the output torque is T1; the load received by the load bearing end is N2, and the output torque is T2. Substituting into the relational expression (4) can obtain the following relational expressions (5) and (6):

[0091] T1 = (2N1 + G)μR + T r (5)

[0092] T2 = (2N2 + G)μR + T r (6)

[0093] Subtracting relational expressions (5) and (6) gives the following relational expression (7):

[0094]

[0095] Wherein, ΔT is the difference between T1 and T2, and ΔN is the difference between N1 and N2.

[0096] Further, when the temperature and pressure in the cavity are the set pressure and the set temperature respectively, multiple groups of data are measured. According to the multiple groups of data, the following relational expression (8) can be obtained:

[0097]

[0098] Wherein, ΔTi is the difference in the output torque corresponding to different loads received at the load-bearing end; ΔNi is the change in the load corresponding to ΔTi; n is the number of differences in the output torque determined. When the temperature and pressure in the cavity are the set pressure and the set temperature respectively, if a groups of data are measured in total by the friction coefficient measurement method provided in the embodiments of the present application, the value of n is less than or equal to the combination number of any two groups of data selected from the a groups of data.

[0099] For example, when the temperature and pressure in the cavity are the set pressure and the set temperature respectively, four groups of data can be measured by the friction coefficient measurement method provided in the embodiments of the present application: the load received at the load-bearing end is N1, and the output torque is T1; the load received at the load-bearing end is N2, and the output torque is T2; the load received at the load-bearing end is N3, and the output torque is T3; the load received at the load-bearing end is N4, and the output torque is T4. Substituting these four groups of data into relational expression (8) can be simplified as follows:

[0100] Or,

[0101]

[0102] In one embodiment, after the step of applying a load to the load-bearing end and controlling the output torque of the driving device connected to the rotating rod, the friction coefficient measurement method further includes:

[0103] Determining the maximum output torque of the driving device before the rotating rod rotates;

[0104] Calculating the static friction coefficient of the material of the rotating part at the set temperature and the set air pressure according to the magnitudes of the respective loads and the corresponding maximum output torque.

[0105] From the time when relative rotation of the rotating part is about to occur but has not yet occurred, the output torque of the driving device reaches the maximum value. The output torque of the driving device during the process from the start of output torque to the uniform rotation of the rotating part can be recorded. Among all the output torques, the maximum value of the output torque is the maximum output torque.

[0106] In one embodiment, in the step of calculating the static friction coefficient of the material of the rotating part under the set temperature and the set air pressure according to the magnitudes of the respective loads and the corresponding maximum output torques, the following relational expression (9) is used to calculate the static friction coefficient:

[0107]

[0108] Wherein, μ’ is the static friction coefficient; R is the rotation radius of the rotating part; ΔTmi is the difference between the maximum output torques corresponding to different loads received at the load bearing end; ΔNi is the change amount of the load corresponding to ΔXi; m is the number of determined differences of the maximum output torques.

[0109] The derivation process of the relational expression (9) is similar to that of the relational expression (8), and will not be elaborated here.

[0110] In one embodiment, in the above steps 110 to 140, by changing the set temperature and the set pressure, the dynamic friction coefficient of the material of the rotating part 40 under different working conditions can be measured; by changing the rotation speed during the uniform rotation of the rotating part, the dynamic friction coefficient of the material of the rotating part 40 at different rotation speeds of the rotating part 40 can be measured. Through experiments, it can be found that the dynamic friction coefficient of the material of the rotating part 40 at different rotation speeds of the rotating part 40 remains unchanged.

[0111] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included within the scope of protection of this application.

Claims

1. A friction coefficient measuring device, characterized in that: The friction coefficient measuring device comprises: A shell; a sealed cavity is provided inside the shell; A bearing structure, located in the cavity, and provided with a bearing surface; A load transfer structure is located above the load-bearing surface; an end of the load transfer structure facing the load-bearing surface is located in the cavity, and a load-bearing end of the load transfer structure away from the load-bearing surface is exposed from the housing; a rotating part, located in the cavity and between the bearing surface and the load transfer structure, the rotating part is in contact with the bearing surface and the surface of the load transfer structure facing the bearing surface respectively; the rotating part, the bearing structure and the part of the load transfer structure in contact with the rotating part are made of the same material; A rotating rod is connected to the rotating part, and an end away from the rotating part is exposed from the shell; the rotating rod can rotate relative to the shell to drive the rotating part to rotate between the bearing surface and the load transfer structure.

2. The friction coefficient measuring device according to claim 1, characterized in that: The load transfer structure comprises a connecting rod and a pressing plate connected to an end of the connecting rod facing the bearing surface, wherein an orthographic projection of the pressing plate on a plane where the bearing surface is located covers an orthographic projection of the rotating part on the plane.

3. The friction coefficient measuring device according to claim 1, characterized in that: The shape of the rotating part is spherical.

4. The friction coefficient measuring device according to claim 1, characterized in that: The friction coefficient measuring device further comprises a positioning portion, which is located between the bearing surface and the load transfer structure and abuts against a side surface of the rotating portion away from the rotating rod.

5. The friction coefficient measuring device according to claim 1, characterized in that: The friction coefficient measuring device further comprises a heating element located in the cavity, and the heating element is arranged on at least two opposite sides of the bearing structure.

6. The friction coefficient measuring device according to claim 5, characterized in that: The friction coefficient measuring device also includes a heat insulation structure located in the shell, and the cavity is arranged in the heat insulation structure.

7. The friction coefficient measuring device according to claim 6, characterized in that: The friction coefficient measuring device also includes a heat-insulating material filled between the heat-insulating structure and the shell.

8. The friction coefficient measuring device according to claim 1, characterized in that: The bearing structure is provided with an accommodation space, and the bearing structure comprises a bearing plate and a first side plate and a second side plate located at opposite sides of the accommodation space, the first side plate and the second side plate are respectively connected to the bearing plate, the rotating part is located in the accommodation space, and the surface of the bearing plate facing the load transfer structure is a bearing surface; The friction coefficient measuring device also includes a plurality of positioning rods for positioning the bearing structure in the shell, and the first side plate and the second side plate are respectively connected to the plurality of positioning rods; among the plurality of positioning rods connected to the first side plate, at least two of the positioning rods have different distances from the load-bearing end, and at least two positioning rods are located on opposite sides of the accommodating space; and / or, among the plurality of positioning rods connected to the second side plate, at least two of the positioning rods have different distances from the load-bearing end, and at least two positioning rods are located on opposite sides of the accommodating space.

9. The friction coefficient measuring device according to claim 1, characterized in that: The friction coefficient measuring device further includes a seal, and a seal is provided at a position where the load transfer structure is exposed from the housing and a position where the rotating part is exposed from the housing, respectively.

10. The friction coefficient measuring device according to claim 9, characterized in that: The shell is also provided with a cooling liquid channel for cooling the sealing element by circulating the cooling liquid.

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