A multi-temperature controllable ice friction coefficient measuring instrument

Abstract

The application discloses a kind of ice surface friction coefficient measuring instruments of multiple temperature control, belong to the field of friction testing technology. Including rotating ice making component, sample temperature control component, force measurement component, drive assembly and control acquisition module;Annular groove of rotating bearing disc can freeze annular ice layer in situ, first semiconductor refrigeration module group, second semiconductor refrigeration module can be independently controlled ice surface and sample temperature respectively;Three-dimensional force sensor is connected in series on the normal loading path of clamping part, measures normal pressure, tangential friction force and radial disturbance force;Drive assembly drives annular ice layer unidirectional continuous rotation, sample remains stationary;Control acquisition module acquires signal and calculates friction coefficient.The application solves the problem that existing equipment cannot independently differentiate temperature control, reciprocating reversing interference test data, uses local semiconductor refrigeration, can complete ice making, temperature control and continuous friction test in situ, for ice and material interface friction characteristic test research.

Description

Technical Field

[0001] This invention relates to the field of friction testing technology, specifically to a multi-temperature controllable ice surface friction coefficient measuring instrument. Background Technology

[0002] Frictional behavior between ice and engineering materials is widely observed in cold-region rail transportation, polar scientific research equipment, and winter sports. Because ice forms a quasi-liquid water film on its surface when subjected to pressure or frictional heating, the contact state between the ice surface and the solid is constantly switching between dry ice and material, quasi-liquid water and ice, and liquid water and ice. The interface temperature is the core variable determining this phase transition process and the transformation of the friction mechanism. To accurately reproduce the frictional characteristics of ice under real-world conditions, the experimental setup must not only provide stable relative motion but also precisely lock the two key boundary conditions: ice surface temperature and sample temperature.

[0003] Existing methods often employ integrated low-temperature test chambers equipped with reciprocating friction mechanisms. An ice mold and a slider are placed within a sealed chamber, utilizing the low-temperature air inside to simultaneously envelop both the ice and the sample. A motor drives the slider to perform linear reciprocating motion on the ice surface to obtain friction data. However, due to differences in heat capacity and thermal conductivity between the ice, the sample, and the fixtures, relying solely on air convection heat transfer within the chamber cannot eliminate the temperature gradient between them. This results in the actual contact area temperature on the ice surface constantly drifting uncontrollably. Furthermore, the reciprocating motion mode means the slider inevitably undergoes deceleration, reversal, and acceleration at each stroke endpoint. This not only interrupts the continuous acquisition window of effective data but also continuously interferes with the water film formation process at the friction interface due to changes in the direction of motion, failing to simulate the unidirectional continuous shearing state in a real-world scenario. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems in the prior art and provide a multi-temperature controllable ice surface friction coefficient measuring instrument.

[0005] This invention provides a multi-temperature controllable ice surface friction coefficient measuring instrument, including a rotating ice-making assembly, which includes a rotating support plate with an annular groove for in-situ freezing to form an annular ice layer. A first semiconductor refrigeration module is thermally connected to the bottom of the annular groove for independently controlling the ice surface temperature. A sample temperature control assembly is disposed above the annular ice layer, including a clamping part for holding the test sample and a second semiconductor refrigeration module thermally connected to the clamping part for independently controlling the sample temperature. A force measurement assembly includes a three-dimensional force sensor, which is connected in series on the normal loading path of the clamping part to keep the test sample stationary while the annular ice layer rotates and to measure normal pressure, tangential friction force, and radial disturbance force. A driving assembly drives the rotating ice-making assembly to rotate continuously in one direction. A control acquisition module is electrically connected to the first semiconductor refrigeration module, the second semiconductor refrigeration module, the three-dimensional force sensor, and the driving assembly, and is configured to calculate the friction coefficient based on the normal force and tangential force.

[0006] Preferably, a rotating connecting disk is fixedly connected below the rotating bearing disk, and a first heat dissipation component is connected to the hot end of the first semiconductor cooling module group. The first heat dissipation component is fixed on the rotating connecting disk. A water slide ring is provided at the central axis of the rotating connecting disk, and the power supply and signal lines of the first semiconductor cooling module group are connected to the control acquisition module via the water slide ring.

[0007] Preferably, an annular cold-conducting plate is provided between the annular groove and the rotating bearing disk, and the cold ends of the first semiconductor refrigeration module group are evenly attached to the lower surface of the annular cold-conducting plate.

[0008] Preferably, the drive assembly includes a drive motor fixed to the bottom of the support frame and a reducer that is drively connected to the drive motor, wherein the output shaft of the reducer drives the rotating bearing disk to rotate through the rotating link disk.

[0009] Preferably, the sample temperature control assembly further includes a sensing bracket, and the clamping part includes a normal pressure adjusting slider, the three-dimensional force sensor and the sample cooling and heat dissipation integrated module connected in sequence, wherein the sample cooling and heat dissipation integrated module has a built-in second semiconductor cooling module.

[0010] Preferably, the normal pressure adjusting slider is a threaded micrometer or a stepper motor driven lead screw, the lower end of which pushes the three-dimensional force sensor, and the lower end of the three-dimensional force sensor presses the test sample through the sample cooling and heat dissipation integrated module.

[0011] Preferably, during the friction process, the control and acquisition module compensates for frictional heat in real time through the first semiconductor cooling module group based on the feedback from the temperature sensor set on the surface of the annular ice layer, so as to maintain a constant ice surface temperature.

[0012] Preferably, the support frame is a non-enclosed frame structure, and both the rotating ice-making assembly and the sample temperature control assembly use local semiconductor refrigeration.

[0013] Compared with the prior art, the beneficial effects of the present invention are: An annular ice layer is generated in situ through the annular groove of the rotating ice-making component. The ice surface and sample temperatures are independently controlled by the first and second semiconductor refrigeration modules, overcoming the shortcomings of existing equipment that rely on overall temperature control of the low-temperature chamber and cannot achieve differentiated temperature control between the ice surface and the sample. The working mode of driving the ice layer to rotate continuously in one direction while keeping the sample stationary is adopted to avoid data truncation interference caused by the reciprocating mechanism's acceleration and deceleration. The three-dimensional force sensor collects the normal pressure, tangential friction force, and radial disturbance force. The control acquisition module calculates the friction coefficient based on this, which can obtain the actual interface force, solve the error caused by the nominal load of the weight, fully reproduce the unidirectional continuous shearing condition of ice friction, and adapt to the testing requirements of the quasi-liquid water film evolution process on the ice surface. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0015] Figure 2 This is a schematic diagram of the sample temperature control component of the present invention.

[0016] Figure 3 This is a schematic cross-sectional view of the overall structure of the present invention.

[0017] Figure 4 This is a partial structural schematic diagram of the present invention.

[0018] Figure 5 This is a top view of the rotating ice-making assembly of the present invention.

[0019] Explanation of reference numerals in the attached drawings: 1. Rotary ice-making assembly; 101. Rotary support plate; 102. Annular ice layer; 103. Annular groove; 104. First semiconductor refrigeration module group; 2. Sample temperature control assembly; 21. Sample refrigeration and heat dissipation integrated module; 22. Three-dimensional force sensor; 23. Sensing bracket; 3. Test sample; 4. Drive assembly; 41. Drive motor; 42. Support frame; 43. Reducer; 5. Control and acquisition module; 6. Rotary connecting plate; 7. First heat dissipation assembly; 8. Water slip ring. Detailed Implementation

[0020] The following is in conjunction with the appendix Figures 1-5To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art.

[0021] The terms "first," "second," and similar words used in the patent application specification and claims of this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "inner," "outer," "upper," "lower," "far," "near," "front," and "rear" are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. The drawings in this invention are not strictly drawn to scale; the specific dimensions and quantity of each structure can be determined according to actual needs. The drawings described in this invention are merely structural schematic diagrams.

[0022] This invention provides a multi-temperature controllable ice surface friction coefficient measuring instrument, such as... Figures 1-5 As shown, the system includes a rotating ice-making assembly 1, which includes a rotating support plate 101. The rotating support plate 101 has an annular groove 103 for in-situ freezing to form an annular ice layer 102. A first semiconductor refrigeration module 104 is thermally connected to the bottom of the annular groove 103 for independently controlling the ice surface temperature. A sample temperature control assembly 2 is positioned above the annular ice layer 102. The sample temperature control assembly 2 includes a clamping part for holding the test sample 3, and a second semiconductor refrigeration module thermally connected to the clamping part for independently controlling the sample temperature. Force measurement... The measurement components include a three-dimensional force sensor 22, which is connected in series on the normal loading path of the clamping part to keep the test sample 3 stationary when the annular ice layer 102 rotates and to measure the normal pressure, tangential friction force and radial disturbance force; a drive component 4, which is used to drive the rotating ice-making component 1 to rotate continuously in one direction; and a control acquisition module 5, which is electrically connected to the first semiconductor refrigeration module group 104, the second semiconductor refrigeration module, the three-dimensional force sensor 22 and the drive component 4, and is configured to calculate the friction coefficient based on the normal force and tangential force.

[0023] In this embodiment, an annular ice layer 102 is generated in situ through the annular groove 103 of the rotating ice-making component 1. The ice surface and sample temperatures are independently controlled by the first semiconductor refrigeration module group 104 and the second semiconductor refrigeration module, overcoming the shortcomings of existing equipment that rely on overall temperature control of the low-temperature chamber and cannot achieve differentiated temperature control between the ice surface and the sample. The working mode of driving the ice layer to rotate continuously in one direction while keeping the sample stationary is adopted to avoid data truncation interference caused by the reciprocating mechanism's acceleration and deceleration. The three-dimensional force sensor 22 collects the normal pressure, tangential friction force, and radial disturbance force, and the control acquisition module 5 calculates the friction coefficient accordingly, which can obtain the actual interface force, solve the error caused by the nominal load of the weight, fully reproduce the unidirectional continuous shearing condition of ice friction, and adapt to the testing requirements of the quasi-liquid water film evolution process on the ice surface. The sliding friction coefficient of the ice surface is equal to the ratio of the tangential friction force and the normal force generated at the contact surface. Tangential friction force is the resistance that hinders the relative sliding of objects along the contact surface of the ice surface. The normal force is the compressive force pointing perpendicularly to the ice surface; when placed horizontally, it is generally equal to the pressure exerted by the object on the ice surface. Simply put, the coefficient of friction is the result of dividing the frictional resistance parallel to the ice surface by the force acting perpendicularly on the ice surface.

[0024] Preferred, such as Figures 3-4 As shown, a rotating connecting disk 6 is fixedly connected below the rotating bearing disk 101. The hot end of the first semiconductor cooling module group 104 is connected to a first heat dissipation component 7, which is fixed on the rotating connecting disk 6. A water slide ring is provided at the central axis of the rotating connecting disk 6. The power supply and signal lines of the first semiconductor cooling module group 104 are connected to the control acquisition module 5 via the water slide ring.

[0025] In this embodiment, a rotating connecting disk 6 is provided below the rotating support disk 101, and the first heat dissipation component 7 is installed on the rotating connecting disk 6 to provide heat dissipation for the hot end of the first semiconductor refrigeration module group 104 in the rotating state. A water-cooled slip ring is used to realize the power supply and signal transmission of the refrigeration module on the rotating component, solving the problem of cable entanglement and breakage during rotation. This overcomes the shortcoming of the existing technology where the refrigeration and temperature measurement circuits cannot be stably led out during ice mold rotation, ensuring the continuous and stable operation of the first semiconductor refrigeration module group 104 during rotation, and ensuring uninterrupted ice surface temperature control signals and power supply, avoiding ice surface temperature drift due to circuit faults, and improving the long-term operational reliability of the rotating ice-making component 1.

[0026] Preferred, such as Figures 3-4 As shown, an annular cold-conducting plate is provided between the annular groove 103 and the rotating bearing disk 101, and the cold ends of the first semiconductor cooling module group 104 are evenly attached to the lower surface of the annular cold-conducting plate.

[0027] In this embodiment, an annular cold-conducting plate is added between the annular groove 103 and the rotating bearing disk 101, and the cold ends of the first semiconductor cooling module group 104 are evenly attached to the lower surface of the annular cold-conducting plate. This allows the cooling energy of the semiconductor cooling module to be evenly conducted to the entire annular groove 103, avoiding uneven circumferential temperature distribution of the annular ice layer 102 caused by localized cooling, and solving the problem of localized overcooling and localized overheating of the ice surface that occurs when directly attaching the cooling module. This ensures consistent icing conditions throughout the annular groove 103, generating a uniformly heated annular ice layer 102, eliminating the additional interference caused by the circumferential temperature gradient of the ice surface on the friction test results, and improving the uniformity of ice surface temperature control and test repeatability.

[0028] Preferred, such as Figures 1-3 As shown, the drive assembly 4 includes a drive motor 41 fixed to the bottom of the support frame 42 and a reducer 43 that is connected to the drive motor 41 in a transmission manner. The output shaft of the reducer 43 drives the rotating bearing disk 101 to rotate through the rotating link disk 6.

[0029] In this embodiment, the limited drive assembly 4 consists of a drive motor 41 and a reducer 43 mounted at the bottom. The output shaft of the reducer 43 drives the rotating bearing disk 101 to rotate via the rotating connecting disk 6. The motor is arranged at the bottom of the frame, and the transmission is amplified and the speed is adjusted by the reducer 43, so that the speed of the annular ice layer 102 can be precisely controlled, and different sliding linear velocities can be output to adapt to various ice friction test conditions. At the same time, the drive component is isolated from the ice surface cooling area, so it does not need to enter the low temperature environment. This overcomes the problems of frost formation, lubrication failure, and sensor zero-point drift that occur when the drive mechanism of existing reciprocating equipment is placed in a low temperature chamber, and extends the service life of the drive component.

[0030] Preferred, such as Figures 1-4 As shown, the sample temperature control component 2 also includes a sensing bracket 23, and the clamping part includes a normal pressure adjustment slider, a three-dimensional force sensor 22 and a sample cooling and heat dissipation integrated module 21 connected in sequence. The sample cooling and heat dissipation integrated module 21 has a built-in second semiconductor cooling module.

[0031] In this embodiment, the sample temperature control component 2 includes a sensing bracket 23. The clamping part is composed of a normal pressure adjusting slider, a three-dimensional force sensor 22, and a sample cooling and heat dissipation integrated module 21 with a built-in second semiconductor cooling module connected in sequence. The sensing bracket 23 provides an installation benchmark and positioning support for the entire sample clamping, force measurement, and temperature control components. The sample cooling and heat dissipation integrated module 21 integrates a second semiconductor cooling module, directly implementing contact-type local cooling for the test sample 3, without relying on ambient air heat exchange for temperature control. This solves the defects of existing devices that rely on air heat exchange within the chamber, resulting in temperature lag and large temperature gradients, achieving rapid and accurate temperature control of the sample and ensuring that the sample temperature is independently adjustable.

[0032] Preferred, such as Figures 1-2As shown, the normal pressure adjustment slider is a threaded micrometer or a stepper motor driven screw, the lower end of which pushes the three-dimensional force sensor 22. The lower end of the three-dimensional force sensor 22 is pressed against the test sample 3 through the sample cooling and heat dissipation integrated module 21.

[0033] In this embodiment, the limiting normal pressure adjustment slider uses a micrometer head or a stepper motor-driven lead screw to push the three-dimensional force sensor 22 downwards, pressing the test sample 3 firmly through the sample cooling and heat dissipation integrated module 21. The normal load can be applied manually or electrically automatically. The load is collected in real time by the three-dimensional force sensor 22. Unlike traditional weight loading, which only obtains the nominal load, this provides real-time feedback on the actual contact pressure between the sample and the ice surface. This compensates for load fluctuations caused by minor unevenness in the ice surface, eliminates the inconsistency between the preset clamping amount and the actual contact load, improves the accuracy of normal loading, and reduces systematic errors in the friction coefficient calculation.

[0034] Preferred, such as Figures 1-3 As shown, during the friction process, the control acquisition module 5 compensates for frictional heat in real time through the first semiconductor cooling module group 104 based on the feedback from the temperature sensor set on the surface of the annular ice layer 102, so as to maintain a constant ice surface temperature.

[0035] In this embodiment, the limited control acquisition module 5, based on the feedback signal from the ice surface temperature sensor, compensates for frictional heat in real time through the first semiconductor cooling module group 104 to maintain a constant ice surface temperature. Addressing the issue of localized temperature rise on the ice surface caused by interfacial frictional heat during the friction process, this method no longer relies on passive stabilization of the ambient temperature but directly implements active thermal compensation on the ice surface, quickly offsetting the heat generated by friction and suppressing temperature drift in the ice surface contact area. This solves the shortcomings of existing equipment where the ice surface temperature is uncontrolled during the friction process and easily rises and softens, forming an excess water film, ensuring that the ice surface temperature remains stable at the set value throughout the experiment and guaranteeing controllable phase transition conditions at the ice sample interface.

[0036] Preferred, such as Figures 1-3 As shown, the support frame 42 is a non-enclosed frame structure, and both the rotating ice-making component 1 and the sample temperature control component 2 adopt local semiconductor refrigeration.

[0037] In this embodiment, the support frame 42 adopts a non-enclosed frame structure, and the rotating ice-making assembly 1 and the sample temperature control assembly 2 employ localized semiconductor cooling. This eliminates the need for a completely sealed cryogenic chamber for overall cooling; cooling is only applied to the ice surface and the test sample 3, significantly reducing the overall heat capacity, shortening the pre-cooling time, and resulting in a smaller device size. Simultaneously, components such as the motor and sensors are kept in a normal-temperature frame environment, avoiding condensation and frost formation on components inside a sealed cryogenic chamber, as well as sensor zero-point drift malfunctions, reducing equipment costs, and facilitating observation of the sample-ice surface contact state during the test.

[0038] The method of using the multi-temperature controllable ice surface friction coefficient measuring instrument of the present invention is as follows: Add a certain amount of pure water into the annular groove 103 of the rotating bearing disk 101, start the first semiconductor cooling module group 104, and freeze in situ in the groove to form an annular ice layer 102; clamp and fix the test sample 3, turn on the second semiconductor cooling module, and set the target ice surface temperature and sample temperature respectively, and wait for the readings of the ice surface and sample temperature sensors to stabilize to the set parameters; debug the equipment, complete the calibration of the three-dimensional force sensor 22, and check that the water slip ring and the connection of each signal line are normal.

[0039] The normal pressure adjustment slider is operated to feed downwards, pressing the test sample 3 firmly onto the surface of the annular ice layer 102. The actual normal pressure is read by the three-dimensional force sensor 22 to the test set load. The drive component 4 is started to drive the rotating bearing disk 101 to rotate continuously in one direction, and the annular ice layer 102 generates continuous sliding friction relative to the stationary test sample 3. The control acquisition module 5 collects data on ice surface temperature, sample temperature, normal pressure, tangential friction force, and radial disturbance force of the three-dimensional force sensor 22 in real time, and calculates the friction coefficient in real time based on the normal force and tangential friction force.

[0040] After completing the friction test for the set duration, stop the rotation of the drive component 4, lift the normal pressure adjustment slider to remove the sample from the ice surface; turn off the semiconductor cooling module, and clean the residual water in the annular groove 103 after the ice surface melts; export the stored temperature, force, and friction coefficient test data; clean the test sample 3 to complete the entire test. If the test needs to be repeated, water can be added to the annular groove 103 again to make ice again and carry out the next set of tests.

[0041] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-temperature controllable ice surface friction coefficient measuring instrument, characterized in that, include: A rotating ice-making assembly includes a rotating support plate, on which an annular groove is formed for in-situ freezing to form an annular ice layer. The bottom of the annular groove is thermally connected to a first semiconductor refrigeration module group for independently controlling the ice surface temperature. A sample temperature control assembly is disposed above the annular ice layer. The sample temperature control assembly includes a clamping part for clamping the test sample and a second semiconductor refrigeration module that is thermally connected to the clamping part for independently controlling the sample temperature. The force measurement component includes a three-dimensional force sensor, which is connected in series on the normal loading path of the clamping part to keep the test sample stationary when the annular ice layer rotates and to measure the normal pressure, tangential friction force and radial disturbance force. A drive component is used to drive the rotating ice-making component to rotate continuously in one direction; The control acquisition module is electrically connected to the first semiconductor cooling module group, the second semiconductor cooling module, the three-dimensional force sensor and the drive component, respectively, and is configured to calculate the friction coefficient based on the normal force and the tangential force.

2. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, A rotating connecting disk is fixedly connected below the rotating bearing disk. The hot end of the first semiconductor cooling module group is connected to a first heat dissipation component, which is fixed on the rotating connecting disk. A water slide ring is provided at the central axis of the rotating connecting disk. The power supply and signal lines of the first semiconductor cooling module group are connected to the control acquisition module via the water slide ring.

3. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, An annular cold-conducting plate is provided between the annular groove and the rotating bearing disk, and the cold ends of the first semiconductor refrigeration module group are evenly attached to the lower surface of the annular cold-conducting plate.

4. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, The drive assembly includes a drive motor fixed to the bottom of the support frame and a reducer that is connected to the drive motor in a transmission manner. The output shaft of the reducer drives the rotating bearing disk to rotate through the rotating link disk.

5. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, The sample temperature control assembly also includes a sensing bracket, and the clamping part includes a normal pressure adjustment slider, the three-dimensional force sensor and the sample cooling and heat dissipation integrated module connected in sequence, wherein the sample cooling and heat dissipation integrated module has a built-in second semiconductor cooling module.

6. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 5, characterized in that, The normal pressure adjustment slider is a threaded micrometer or a stepper motor driven lead screw, the lower end of which pushes the three-dimensional force sensor, and the lower end of the three-dimensional force sensor presses the test sample through the sample cooling and heat dissipation integrated module.

7. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, During the friction process, the control and acquisition module compensates for frictional heat in real time through the first semiconductor cooling module group based on the feedback from the temperature sensor set on the surface of the annular ice layer, so as to maintain a constant ice surface temperature.

8. The multi-temperature controllable ice surface friction coefficient measuring instrument as described in claim 1, characterized in that, The support frame is a non-enclosed frame structure, and both the rotating ice-making component and the sample temperature control component use local semiconductor refrigeration.

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