Frictional interface molecular in-situ measurement device

Abstract

This invention relates to an in-situ molecular measurement device for a friction interface. The device includes a base, a housing, a temperature control element, a friction testing mechanism, and a sum-frequency spectroscopy detection mechanism. The base has a receiving cavity with an inlet and an outlet connected to it. The top of the base is configured as a detection platform. The housing is situated on the detection platform and has a receiving cavity. The temperature control element is located within the receiving cavity and includes a solution pool. The inlet and outlet are connected to the solution pool via pipes. The friction testing mechanism is located within the receiving cavity and is used to detect the friction performance of the workpiece. The sum-frequency spectroscopy detection mechanism is located on the housing and is used to detect the behavior of lubricating molecules on the friction surface of the workpiece. This structural design allows for real-time measurement of the friction performance of two friction pairs at different temperatures and the molecular behavior within the lubricating film at the friction interface.

Description

Technical Field

[0001] This invention relates to the field of optical measurement equipment technology, and in particular to an in-situ molecular measurement device for friction interfaces. Background Technology

[0002] Water possesses unique physical and chemical properties due to its complex hydrogen bond network. The interaction between water and its surroundings occurs through interfacial contact, with numerous physical and chemical processes occurring at the water-solid-liquid interface. For example, friction in aquatic environments involves interfacial shearing of water molecules. Studying the laws governing interfacial shearing and the interactions of interfacial hydrogen bonds helps to reveal the mechanisms of friction generation. The study of interfacial shearing laws and the elucidation of friction reduction mechanisms have a significant impact on the long-term, efficient operation, accuracy, and lifespan of equipment. Reducing interfacial shear forces can significantly reduce economic losses caused by friction, wear, and resistance. For instance, typical interfacial shearing problems in cryogenic equipment include scientific issues related to ice and snow surfaces, as well as solid-liquid interfacial shearing and friction problems of moving pairs in equipment operating in cryogenic seawater environments. Cryogenic conditions affect the frictional performance of critical mechanical components. Reducing ice surface friction can effectively improve the performance of ice sports equipment and also reduce energy consumption and conserve resources in marine equipment. The tribological properties of critical components are easily affected by temperature, speed, and pressure, significantly impacting the operational stability, accuracy, and lifespan of equipment. Therefore, it is urgent to study frictional performance at different temperatures, and clarifying the behavioral changes of interfacial water molecules during shearing is fundamental to revealing the laws governing cryogenic friction. Summary of the Invention

[0003] Therefore, it is necessary to provide an in-situ molecular measurement device for the friction interface to address the technical problem that the friction performance of related products cannot be tested at different temperatures.

[0004] A device for in-situ measurement of molecules at a friction interface, the device comprising:

[0005] The base has a receiving cavity, and the base is provided with an inlet and an outlet that communicate with the receiving cavity. The top of the base is configured as a detection platform.

[0006] A housing is disposed on the detection platform, and a receiving cavity is constructed on the housing;

[0007] A temperature control element is disposed within the receiving cavity. The temperature control element is configured with a solution pool. The inlet and outlet are connected to the solution pool via pipelines.

[0008] A friction testing mechanism, located within the accommodating cavity, is used to test the frictional properties of the workpiece under test.

[0009] A sum-frequency spectral detection mechanism, disposed on the housing, is used to detect the behavior of lubricating molecules on the friction surface of the workpiece.

[0010] In one embodiment, the friction testing mechanism includes:

[0011] A rotating friction assembly, mounted on the detection platform, enables relative rotation of the two friction pairs;

[0012] A reciprocating friction assembly, mounted on the detection platform, enables relative linear movement of two friction pairs;

[0013] Either the rotary friction assembly or the reciprocating friction assembly is connected to the detection platform.

[0014] In one embodiment, the rotary friction assembly includes:

[0015] A first drive motor is fixedly disposed within the receiving cavity, and the motor shaft of the first drive motor extends into the receiving cavity of the housing.

[0016] A rotating disk is connected to the motor shaft of the first drive motor. The rotating disk is fixedly connected to one of the friction pairs so that the friction pair connected to the rotating disk rotates relative to the other friction pair.

[0017] In one embodiment, the reciprocating friction assembly includes:

[0018] A second drive motor is fixedly disposed within the receiving cavity, and the motor shaft of the second drive motor extends into the receiving cavity of the housing.

[0019] A transmission assembly is connected to the motor shaft of the second drive motor;

[0020] A support plate is connected to the transmission assembly, and the support plate is used to fix one of the two friction pairs;

[0021] The transmission component can convert the rotational motion of the motor shaft of the second drive motor into linear motion, so as to drive the support plate to reciprocate.

[0022] In one embodiment, the in-situ molecular measurement device for the friction interface further includes:

[0023] A loading mechanism is movably connected to the housing and is capable of applying a preset load between the two friction pairs.

[0024] In one embodiment, the in-situ molecular measurement device for the friction interface further includes a clamping mechanism, the clamping mechanism comprising:

[0025] The connecting seat has a notch, and one sidewall corresponding to the notch is detachably connected to the loading mechanism;

[0026] Mounting base, wherein the mounting base is detachably connected to the other side wall corresponding to the recess;

[0027] The mounting base is used to connect one of the friction pairs.

[0028] In one embodiment, the in-situ molecular measurement device at the friction interface further includes a humidity control module, the humidity control module comprising:

[0029] A spray pipe is disposed inside the accommodating cavity and connected to a water vapor channel on the shell. The spray pipe is capable of spraying water vapor into the accommodating cavity.

[0030] A humidity monitoring device is disposed inside the accommodating cavity and is used to detect the humidity value inside the accommodating cavity.

[0031] In one embodiment, the in-situ molecular measurement device for the friction interface further includes a vacuum module, the vacuum module comprising:

[0032] A vacuum pump, connected to a vacuum pipe interface on the housing, is used to provide a vacuum environment for the accommodating cavity of the housing.

[0033] In one embodiment, the housing includes:

[0034] The shell body has an opening for operation;

[0035] The door body is used to block and seal the operating port.

[0036] In one embodiment, the sum-frequency spectral detection mechanism includes:

[0037] A visible light source is located outside the housing, and the visible light emitted by the visible light source can pass through the light-transmitting window on the housing and illuminate the contact area between the two friction pairs;

[0038] An infrared light source is located outside the housing. The infrared light emitted by the infrared light source can pass through the light-transmitting window on the housing and illuminate the contact area between the two friction pairs.

[0039] The visible light and the infrared light overlap in time and space to form a sum-frequency spectrum.

[0040] The beneficial effects of this invention are:

[0041] This invention provides an in-situ molecular measurement device for friction interfaces. The device includes a base, a housing, a temperature control element, a friction testing mechanism, and a sum-frequency spectroscopy detection mechanism. A cavity is constructed on the base to accommodate pipes and other components. An inlet and outlet are provided on the base, communicating with the cavity, so that the temperature control element located within the cavity is connected to the inlet and outlet of the base. This allows the solution pool of the temperature control element to be connected to an external circulating fluid system via pipes, providing the temperature control element with a circulating fluid for temperature control. This facilitates heat exchange between the circulating fluid in the solution pool of the temperature control element and the air within the cavity, enabling the cavity and testing platform to reach a preset temperature. A housing is installed on the testing platform, allowing the friction performance testing of the friction pair to be performed in a closed environment. The solution pool on the temperature control element facilitates heat exchange between the circulating fluid and the air within the cavity, thereby controlling the temperature of the cavity and testing platform. Understandably, since the housing cavity of the shell is adjacent to the housing cavity of the base, the temperature inside the housing cavity of the shell adapts to the temperature of the testing platform due to heat transfer. A friction testing mechanism is installed within the housing cavity to facilitate the detection of the frictional performance between the two friction pairs. A sum-frequency spectroscopy detection mechanism is installed on the shell to facilitate the detection of the lubricating molecular behavior between the two friction pairs. Through this structural configuration, the frictional performance between the two friction pairs is detected by the friction testing mechanism, while the sum-frequency spectroscopy detection mechanism measures the lubricating molecular behavior between the two friction pairs in real time. The temperature inside the housing cavity and the testing platform is controlled by a temperature controller, thereby achieving real-time measurement of the frictional performance of the two friction pairs and the molecular behavior within the lubricating film at the friction interface at different temperatures. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the external contour of a friction interface molecular in-situ measurement device provided in an embodiment of the present invention.

[0043] Figure 2 This is a schematic diagram of the internal structure of a friction interface molecular in-situ measurement device provided in an embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the internal structure of the friction pair lower plate protective cover in the in-situ molecular measurement device for the friction interface provided in an embodiment of the present invention.

[0045] Figure 4 This is a schematic diagram of the internal structure of a friction interface molecular in-situ measurement device provided in an embodiment of the present invention from another perspective.

[0046] Figure 5 This is a schematic diagram illustrating the principle of real-time in-situ measurement of molecular behavior at a friction interface, provided in an embodiment of the present invention.

[0047] Figure label:

[0048] 100, Base; 110, Liquid Inlet; 120, Liquid Outlet; 130, Water Vapor Channel; 140, Testing Platform; 200, Housing; 210, Housing Body; 211, Light Transmitting Window; 220, Door; 300, Friction Testing Mechanism; 310, Reciprocating Friction Assembly; 311, Second Drive Motor; 312, Support Plate; 313, Lower Friction Pair Protective Cover; 400, Loading Mechanism; 410, Loading Base; 420, Connecting Seat; 500, Clamping Mechanism; 510, Connecting Seat; 520, Mounting Seat; 600, Displacement Mechanism; 610, Support Plate; 620, First Connecting Plate; 630, Second Connecting Plate; 640, Driving Component; 700, Upper Friction Pair; 800, Lower Friction Pair. Detailed Implementation

[0049] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0050] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0055] See Figures 1 to 4 An embodiment of the present invention provides an in-situ measurement device for molecules at a friction interface. The in-situ measurement device for molecules at a friction interface includes a base 100, a housing 200, a temperature control element, a friction testing mechanism 300, and a sum-frequency spectroscopy detection mechanism. The base 100 has a receiving cavity and is provided with an inlet 110 and an outlet 120 communicating with the receiving cavity. The top of the base 100 is configured as a detection platform 140. The housing 200 is disposed on the detection platform 140 and has a receiving cavity. The temperature control element is disposed in the receiving cavity and has a solution pool. The inlet 110 and the outlet 120 are connected to the solution pool through pipelines. The friction testing mechanism 300 is disposed in the receiving cavity and is used to detect the friction performance of the workpiece under test. The sum-frequency spectroscopy detection mechanism is disposed on the housing 200 and is used to detect the behavior of lubricating molecules on the friction surface of the workpiece.

[0056] This technical solution provides an in-situ molecular measurement device for a friction interface. The device includes a base 100, a housing 200, a temperature control element, a friction testing mechanism 300, and a sum-frequency spectral detection mechanism. A cavity is constructed on the base 100 to accommodate pipes and other components. An inlet 110 and an outlet 120 connected to the cavity are provided on the base 100, allowing the temperature control element within the cavity to communicate with these inlets and outlets. This allows the solution pool of the temperature control element to be connected to an external circulating fluid system via pipes, providing the temperature control element with a circulating fluid to regulate its temperature. This allows heat exchange between the circulating fluid in the solution pool of the temperature control element and the air within the cavity, enabling the cavity and the testing platform 140 to reach a preset temperature. The housing 200 is installed on the testing platform 140, ensuring that the friction performance of the friction pair is tested in a sealed environment. A solution pool is constructed on the temperature control element to accommodate the circulating fluid, facilitating heat exchange between the circulating fluid and the air in the containment cavity, thereby controlling the temperature of the containment cavity and the detection platform 140. It is understood that, since the containment cavity of the housing 200 is adjacent to the containment cavity of the base 100, the temperature within the containment cavity of the housing 200 adapts to the temperature of the detection platform 140 under the influence of heat transfer. A friction testing mechanism 300 is installed within the containment cavity to facilitate the detection of the frictional performance between the two friction pairs. A sum-frequency spectroscopy detection mechanism is installed on the housing 200 to facilitate the detection of the lubricating molecular behavior between the two friction pairs. Through the above structural configuration, the frictional performance between the two friction pairs is detected by the friction testing mechanism 300, while the sum-frequency spectroscopy detection mechanism measures the lubricating molecular behavior between the two friction pairs in real time. The temperature control element controls the temperature within the containment cavity of the housing 200 and the detection platform 140, thereby achieving real-time measurement of the frictional performance of the two friction pairs and the molecular behavior within the lubricating film at the friction interface at different temperatures.

[0057] In this embodiment, the base 100 is a box-like structure. The temperature control element is fixedly connected to the top sidewall of the base 100 and fits against the top sidewall of the base 100. It should be noted that the temperature control element in the in-situ molecular measurement device of the friction interface provided in this application can control the temperature between -50 ℃ and 100 ℃, with a control accuracy of ±1 ℃. Specifically, a circulating fluid system provides the temperature control element with a circulating fluid at a preset temperature. The circulating fluid enters the solution pool of the temperature control element through the inlet 110 on the base 100. After heat exchange in the receiving cavity, the circulating fluid flows back into the circulating fluid system through the outlet 120, thereby realizing the circulation of the circulating fluid. Furthermore, a temperature sensor is provided in the receiving cavity and the accommodating cavity. The temperature sensor is communicatively connected to the control unit. The control unit can control the temperature of the circulating fluid in the circulating fluid system according to the detection result of the temperature sensor, thereby ensuring that the temperature in the receiving cavity and the accommodating cavity is kept within the preset value range.

[0058] Furthermore, the temperature control component and the top of the base 100 can be integrally formed components. In other words, a solution pool can be provided on the top of the base 100, connecting the liquid inlet 110 and the liquid outlet 120 of the base 100 to the solution pool on the top of the base 100. This arrangement allows the circulating liquid to directly exchange heat with the detection platform 140, thereby controlling the temperature of the accommodating cavity and enabling the frictional performance of the two friction pairs to be detected within a preset temperature range.

[0059] Furthermore, the circulating fluid in the circulating fluid system can be either a cooled low-temperature circulating fluid or a heated high-temperature circulating fluid, which can be selected according to experimental requirements. The temperature control described above enables friction performance testing of the friction pairs under various temperature conditions, such as ice surface friction, low-temperature lubrication, and high-temperature lubrication. In one embodiment, the friction testing mechanism 300 includes a rotary friction component and a reciprocating friction component 310. The rotary friction component is mounted on the testing platform 140 and enables relative rotation of the two friction pairs; the reciprocating friction component 310 is mounted on the testing platform 140 and enables relative linear movement of the two friction pairs; wherein either the rotary friction component or the reciprocating friction component 310 is selectively connected to the testing platform 140.

[0060] In this embodiment, a rotary friction assembly is used to achieve relative rotation of the two friction pairs, thereby detecting their rotational friction performance. A reciprocating friction assembly 310 is mounted on the detection platform 140 to achieve relative linear movement of the two friction pairs, thereby detecting their reciprocating friction performance. Specifically, either the rotary friction assembly or the reciprocating friction assembly 310 can be connected to the detection platform 140 according to the detection requirements, thereby enabling the detection of the corresponding friction performance of the two friction pairs. This configuration improves the applicability of the in-situ molecular measurement device at the friction interface. It is understood that in this embodiment, the two friction pairs are the upper friction pair and the lower friction pair.

[0061] like Figure 2 As shown, in one embodiment, the in-situ molecular measurement device for the friction interface further includes a loading mechanism 400, which is movably connected to the housing 200 and is capable of applying a preset load between the two friction pairs.

[0062] A preset load is applied between the two friction pairs by the loading mechanism 400, so that the upper friction pair can generate a positive pressure on the lower friction pair under the action of the preset load. The positive pressure is overcome by the rotating friction assembly or the reciprocating friction assembly 310, so that one friction pair can rotate or move relative to the other friction pair, thereby testing the rotational friction and reciprocating friction performance between the upper and lower friction pairs.

[0063] like Figure 2 As shown, specifically, the loading mechanism 400 includes a fixed base, a loading base 410, and a driving component 640. The fixed base is supported and fixed on the detection platform 140, and a guide rail is provided on the fixed base. A slider is provided on the loading base 410, and the slider on the loading base 410 guides and cooperates with the guide rail. The driving component 640 can be a hydraulic cylinder or a pneumatic cylinder. The cylinder body of the driving component 640 is fixedly connected to the fixed base, and the loading base 410 is fixedly connected to the piston rod of the driving component 640. The piston rod of the driving component 640 drives the loading base 410 to move relative to the fixed base.

[0064] A three-dimensional force sensor is installed on the upper friction pair. The measurement range in the transverse and longitudinal directions is between 0-10N, and the measurement range in the Z direction is between 0-20N. The measurement accuracy is 0.3%.

[0065] In one embodiment, the in-situ molecular measurement device for the friction interface further includes a clamping mechanism 500, which includes a connecting seat 510 and a mounting seat 520. The connecting seat 510 has a notch, and one sidewall corresponding to the notch is detachably connected to the loading mechanism 400. The mounting seat 520 is detachably connected to the other sidewall corresponding to the notch. The mounting seat 520 is used to connect the upper friction pair 700.

[0066] The connecting seat 510 is used to connect the mounting seat 520 and the loading base 410. By providing a notch in the connecting seat 510, the weight of the connecting seat 510 can be reduced, and the notch provides clearance for the connection between the mounting seat 520 and the loading base 410. Specifically, the connecting seat 510 is a U-shaped structural component, and one sidewall corresponding to the U-shaped notch of the connecting seat 510 is fixedly connected to the loading base 410 by bolts.

[0067] The mounting base 520 has a mounting hole, and an opening communicating with the mounting hole is provided on the side wall corresponding to the mounting hole. Two oppositely spaced protrusions are provided at the opening. One end of the upper friction pair 700 is installed in the mounting hole, and then a fastener passes through a connecting hole on the protrusion to fix the upper friction pair 700. Specifically, in this embodiment, the end face of the upper friction pair 700 connected to the mounting base 520 that faces away from the mounting base 520 can be a plane, a spherical surface, or a curved surface.

[0068] like Figure 2 As shown, in another embodiment, a displacement mechanism 600 is provided between the loading base 410 and the connecting seat 510. The displacement mechanism 600 includes a lateral movement component and a longitudinal movement component. The lateral movement component includes a support plate 610, fixedly connected to the loading base 410. A guide rail extending laterally is provided on the support plate 610. The lateral movement component also includes a first connecting plate 620, with a slider on the first connecting plate 620 guidingly engaging with the guide rail on the support plate 610. The first connecting plate 620 is driven by a cylinder to move relative to the support plate 610. The longitudinal movement component includes a second connecting plate 630. A guide rail extending longitudinally is provided on the side of the first connecting plate 620 opposite to the support plate 610. A slider on the second connecting plate 630 is guidingly engaging with the guide rail on the first connecting plate 620. The second connecting plate 630 is driven by a cylinder to move relative to the first connecting plate 620 in the longitudinal direction. The connecting seat 510 is fixedly connected to the second connecting plate 630. The above-mentioned moving mechanism can drive the clamping mechanism 500 to move relative to the detection platform 140 in the horizontal plane, thereby facilitating the mutual alignment of the upper and lower friction pairs.

[0069] In one embodiment, the rotary friction assembly (not shown) includes a first drive motor and a rotary disk. The first drive motor is fixed in the receiving cavity, and the motor shaft of the first drive motor extends into the receiving cavity of the housing 200. The rotary disk is connected to the motor shaft of the first drive motor and is used to be fixedly connected to one of the friction pairs so that the friction pair connected to the rotary disk rotates relative to the other friction pair.

[0070] A first drive motor is installed within the receiving cavity; specifically, the motor mount of the first drive motor is fixedly connected to the detection platform 140, thereby achieving mutual fixation between the first drive motor and the detection platform 140. By extending the motor shaft of the first drive motor into the receiving cavity of the housing 200, the rotating disk can be fixedly connected to the motor shaft of the first drive motor, enabling the rotating disk to rotate relative to the detection platform 140. Since the rotating disk is used to fixally connect the lower friction pair 800, the rotating disk can drive the lower friction pair 800 to rotate relative to the detection platform 140, thus achieving relative rotation between the two friction pairs.

[0071] In this embodiment, the rotational speed of the rotary friction mechanism is 1-1000 rpm, the movement of the upper friction pair 700 in the horizontal plane is within 50mm, and the adjustment range of the upper friction pair 700 in the vertical direction is within 10cm, with an adjustment accuracy of 0.01mm.

[0072] like Figures 2 to 4 As shown, in one embodiment, the reciprocating friction assembly 310 includes a second drive motor 311, a transmission assembly, and a support disk 312. The second drive motor 311 is fixed in the receiving cavity, and the motor shaft of the second drive motor 311 extends into the receiving cavity of the housing 200. The transmission assembly is connected to the motor shaft of the second drive motor 311. The support disk 312 is connected to the transmission assembly. The transmission assembly can convert the rotational motion of the motor shaft of the second drive motor 311 into linear motion to drive the support disk 312 to reciprocate.

[0073] The second drive motor 311 is fixed to the detection platform 140 by placing it within the receiving cavity and by fixing its motor mount to the detection platform 140. The motor shaft of the second drive motor 311 extends into the internal cavity of the housing 200 to facilitate its connection to the transmission assembly. The support disk 312 is connected to the transmission assembly, allowing the transmission assembly to be driven by the motor shaft of the second drive motor 311, thus causing the support disk 312 to reciprocate. One of the two friction pairs is fixedly connected to the support disk 312, allowing the lower friction pair 800 to move relative to the detection platform 140, thereby testing the frictional performance between the two friction pairs. It is understood that the other friction pair, the upper friction pair 700, is connected to the clamping mechanism 500, and normally the upper friction pair 700 connected to the clamping mechanism 500 remains stationary. The transmission assembly can be a gear and rack transmission mechanism. Specifically, the gear is fixedly connected to the motor shaft of the second drive motor 311, and the support plate 312 is fixedly connected to the rack, with the gear meshing with the rack. It can be understood that the first drive motor and the second drive motor 311 can be the same motor. When replacing the friction assembly, only the above-mentioned parts need to be replaced.

[0074] It should be noted that for ice surface friction, by fixing the prepared ice block to the support plate 312, and then fixing the lower friction pair 800 to the ice surface, and attaching the lower friction pair protective cover 313 to the support plate 312, the temperature of the friction surface can be better guaranteed. The upper surface of the protective cover has pre-drilled circular / strip / square notches for contact between the upper friction pair 700 and the lower friction pair 800. In one embodiment, the in-situ molecular measurement device for the friction interface also includes a humidity control module. The humidity control module includes a spray pipe and a humidity detection element. The spray pipe is located inside the accommodating cavity and is connected to the water vapor channel 130 on the housing 200, allowing the spray pipe to spray water vapor into the accommodating cavity. The humidity detection element is located inside the accommodating cavity and is used to detect the humidity value inside the accommodating cavity.

[0075] A spray pipe (not shown in the figure) is installed inside the accommodating cavity and connected to a water vapor channel 130 on the housing 200. The water vapor channel 130 is connected to a water vapor generating device, allowing water vapor to be sprayed into the accommodating cavity through the spray pipe, thereby regulating the humidity inside the housing 200. A humidity sensor detects the humidity value inside the accommodating cavity, allowing for control of the humidity by opening and closing the spray and adjusting the spray rate. Specifically, the humidity sensor is a humidity detector. The relative humidity inside the accommodating cavity can be controlled between 5% and 85%, with a humidity measurement accuracy of 2%. Specifically, a valve is installed at the opening of the water vapor channel 130. Opening the valve allows water vapor to be sprayed into the accommodating cavity, and the control system controls the opening and closing of the valve based on the humidity detected by the humidity sensor. When the humidity reaches a preset value, the control system closes the valve to stop spraying water vapor into the cavity, thus controlling the humidity at the target value.

[0076] In one embodiment, the in-situ molecular measurement device for the friction interface further includes a vacuum module (not shown in the figure). The vacuum module includes a vacuum pump connected to a vacuum pipe interface on the housing 200. The vacuum pump provides a vacuum environment for the accommodating cavity of the housing 200. By setting up the vacuum module as described above, the vacuum level inside the housing 200 reaches a preset value, thereby enabling the friction performance test to be performed in a vacuum environment. The vacuum pump provided in this application can achieve a vacuum level of over 1 mbar inside the accommodating cavity.

[0077] In one embodiment, the housing 200 includes a housing body 210 and a door 220. The housing body 210 has an operating opening; the door 220 blocks and seals the operating opening. The operating opening on the housing body 210 facilitates access for equipment maintenance, replacement of the rotating friction assembly, and replacement of the reciprocating friction assembly 310. The door 220 blocking the operating opening ensures the sealing of the accommodating cavity of the housing 200. Specifically, a sealing strip is provided at the edge of the door 220 to seal the gap between the housing body 210 and the door 220.

[0078] In one embodiment, the sum-frequency spectral detection mechanism (not shown in the figure) includes a visible light source and an infrared light source. The visible light source is located outside the housing 200, and the visible light emitted by the visible light source can pass through the light-transmitting window 211 on the housing 200 and illuminate the friction area between the two friction pairs. The infrared light source is located outside the housing 200, and the infrared light emitted by the infrared light source can pass through the light-transmitting window 211 on the housing 200 and illuminate the friction area between the two friction pairs. The visible light and infrared light coincide in time and space to form a sum-frequency spectrum.

[0079] Specifically, such as Figure 5As shown, light-transmitting windows 211 are provided on both sides of the housing 200. The window material is light-transmitting, including but not limited to calcium fluoride, sapphire, quartz glass, etc., as long as it can transmit visible and infrared light. The base 100 is placed on an adjustable-height platform. Visible and infrared light enter the receiving cavity through one light-transmitting window and strike the friction area. By adjusting the platform height and the incident angle of the incident light, the two beams of light are made to coincide in time and space, generating a sum-frequency light with a frequency equal to the sum of the two beams. The sum-frequency light is emitted through another light-transmitting window 211, collected, and then enters the spectrometer after polarization conversion, lens, and filter to complete the spectral acquisition. The vertical resolution of the spectrum is monolayer, and the spectral acquisition time resolution is in the millisecond range. The sum-frequency light test site for rotating friction is on the rotating contact surface of the friction, and the sum-frequency light test site for reciprocating friction detection is on the contact surface of the reciprocating stroke. At this time, the behavior of lubricating molecules on the contact surface can be detected, which is beneficial to revealing the physical and chemical changes of molecules during the friction process.

[0080] Reference Figures 1 to 5 It is understood that the method of using the in-situ molecular measurement device at the friction interface provided by the present invention is as follows:

[0081] First, the temperature of the circulating fluid in the circulating fluid system is controlled to reach the preset experimental temperature within the containment chamber. Specifically, the circulating fluid flows from the inlet 110 into the solution pool of the temperature control device. After exchanging heat with the containment chamber, the detection platform 140, and the air within the containment chamber, it flows from the solution pool to the outlet 120. During this process, the temperature detector continuously monitors the temperature within the chamber. After preheating for 5-30 minutes to reach the set temperature, the experiment begins. During preheating, the vacuum interface and humidity control valve are closed. After preheating, the door 220 of the sealed chamber is opened, and the lower friction pair 800 is selected and installed. Specifically, one of the rotary friction assembly or the reciprocating friction assembly 310 is selected according to the experimental requirements, and then the lower friction pair 800 is fixed onto the corresponding friction assembly. For example, if an experiment involving the reciprocating motion of the lower friction pair 800 is desired, the reciprocating friction assembly 310 must be selected for installation. After installing the reciprocating friction assembly 310, the friction pair is fixed on the surface of the support plate 312. Specific fixing methods include direct pasting and fixing via threaded connection using a designed fixture. In one embodiment, the bearing steel disc (the lower friction pair 800) can be pasted to the surface of the support plate 312 using 3M tape. In another embodiment, a designed groove is filled with water, which is then frozen in a -20°C refrigerator. The frozen ice surface is then sanded smooth, parallel to the support plate 312. The sample is then fixed to the support plate 312 via threads. A lower friction pair protective cover 313 is then attached to the outside of the support plate 312 to better ensure the temperature of the friction surface. The upper surface of the protective cover has pre-drilled circular / strip / square notches for contact between the upper friction pair 700 and the lower friction pair 800. Then, install the upper friction pair 700 on the clamp. The upper friction pair 700 can be selected as spherical, cylindrical, or planar, depending on your needs. The diameter of the ball should be between 2-20mm, and ball holders of different sizes can be custom-made according to the size of the ball. If lubricant needs to be added between the friction pairs, it can be dripped onto the surface of the lower friction pair 800.

[0082] After completing the above preparations, close and tighten the door 220. If vacuuming is required, open the vacuum interface and start the vacuum pump. Once the vacuum level reaches approximately 1 mbar, the experiment can begin. Adjust the displacement of the clamping mechanism 500 in the X, Y, and Z directions using the displacement mechanism 600 to ensure contact between the upper and lower friction pairs 800. Set the experimental load, radius, rotational speed, or parameters such as load, reciprocating stroke, and reciprocating frequency. After the loading mechanism 400 begins loading, the force sensor records the loaded load and maintains the load once the set load is reached. At this time, the humidity inside the cavity can be adjusted as needed. The humidity sensor detects the humidity inside the cavity in real time, and the experiment can begin once the preset humidity is reached. Data such as friction force, load, temperature, and humidity are transmitted to the computer via the data transmission interface for analysis of changes in the coefficient of friction. To observe the wear marks, visible light (wavelength approximately 780-1100nm) and infrared light (wavelength approximately 2700-3500nm) are introduced through the light-transmitting window 211 of the housing 200. Adjusting the lens knob on the lens changes the direction and position of the light. The height of the base 100 can also be adjusted using a high-precision displacement adjustment frame to direct both beams of light to the same position on the wear mark (infrared light is invisible to the naked eye but can be indicated by a laser indicator). The reflected sum-frequency light is also guided by the visible laser through the light-transmitting window 211. The collected sum-frequency light passes through polarizer P, lens L, and filter LP before entering the spectrometer and detector. The sum-frequency signal can then be acquired and analyzed on a computer to monitor and analyze the real-time changes in the structure, configuration, and orientation of the lubricating molecules at the friction interface. Analyzing the lubrication state through real-time friction changes and understanding the microscopic mechanisms of friction changes based on changes in the interface molecular structure effectively reveals the underlying mechanisms of friction.

[0083] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A device for in-situ measurement of molecules at a friction interface, characterized in that, The in-situ molecular measurement device at the friction interface includes: The base has a receiving cavity, and the base is provided with an inlet and an outlet that communicate with the receiving cavity. The top of the base is configured as a detection platform. A housing is disposed on the detection platform, and a receiving cavity is constructed on the housing; the receiving cavity of the housing is adjacent to the receiving cavity of the base; A temperature control element is disposed within the receiving cavity. The temperature control element is configured with a solution pool. The inlet and outlet are connected to the solution pool via pipelines, so that the solution pool is connected to an external circulating liquid system via the pipelines. The temperature control element is fixedly connected to the top sidewall of the base and fits against the top sidewall of the base. A temperature sensor is disposed in the receiving cavity and the accommodating cavity. The temperature sensor is communicatively connected to the control unit. The control unit can control the temperature of the circulating fluid in the circulating fluid system according to the detection result of the temperature sensor. A friction testing mechanism, located within the accommodating cavity, is used to test the frictional properties of the workpiece under test. A sum-frequency spectral detection mechanism, disposed on the housing, is used to detect the behavior of lubricating molecules on the friction surface of the workpiece.

2. The in-situ molecular measurement device for the friction interface according to claim 1, characterized in that, The friction testing mechanism includes: A rotating friction assembly, mounted on the detection platform, enables relative rotation of the two friction pairs; A reciprocating friction assembly, mounted on the detection platform, enables relative linear movement of two friction pairs; Either the rotary friction assembly or the reciprocating friction assembly is connected to the detection platform.

3. The in-situ molecular measurement device for the friction interface according to claim 2, characterized in that, The rotary friction assembly includes: A first drive motor is fixedly disposed within the receiving cavity, and the motor shaft of the first drive motor extends into the receiving cavity of the housing. A rotating disk is connected to the motor shaft of the first drive motor. The rotating disk is fixedly connected to one of the friction pairs so that the friction pair connected to the rotating disk rotates relative to the other friction pair.

4. The in-situ molecular measurement device for the friction interface according to claim 2, characterized in that, The reciprocating friction assembly includes: A second drive motor is fixedly disposed within the receiving cavity, and the motor shaft of the second drive motor extends into the receiving cavity of the housing. A transmission assembly is connected to the motor shaft of the second drive motor; A support plate is connected to the transmission assembly, and the support plate is used to fix one of the two friction pairs; The transmission component can convert the rotational motion of the motor shaft of the second drive motor into linear motion, so as to drive the support plate to reciprocate.

5. The in-situ molecular measurement device for the friction interface according to any one of claims 2-4, characterized in that, The in-situ molecular measurement device at the friction interface also includes: A loading mechanism is movably connected to the housing and is capable of applying a preset load between the two friction pairs.

6. The in-situ molecular measurement device for the friction interface according to claim 5, characterized in that, The in-situ molecular measurement device for the friction interface further includes a clamping mechanism, which comprises: The connecting seat has a notch, and one sidewall corresponding to the notch is detachably connected to the loading mechanism; Mounting base, wherein the mounting base is detachably connected to the other side wall corresponding to the recess; The mounting base is used to connect one of the friction pairs.

7. The in-situ molecular measurement device for the friction interface according to claim 1, characterized in that, The in-situ molecular measurement device at the friction interface further includes a humidity control module, which comprises: A spray pipe is disposed inside the accommodating cavity and connected to a water vapor channel on the shell. The spray pipe is capable of spraying water vapor into the accommodating cavity. A humidity monitoring device is disposed inside the accommodating cavity and is used to detect the humidity value inside the accommodating cavity.

8. The in-situ molecular measurement device for the friction interface according to claim 1, characterized in that, The in-situ molecular measurement device at the friction interface further includes a vacuum module, which comprises: A vacuum pump, connected to a vacuum pipe interface on the housing, is used to provide a vacuum environment for the accommodating cavity of the housing.

9. The in-situ molecular measurement device for the friction interface according to claim 1, characterized in that, The housing includes: The shell body has an operating port. The door body is used to block and seal the operating port.

10. The in-situ molecular measurement device for the friction interface according to claim 1, characterized in that, The sum-frequency spectral detection mechanism includes: A visible light source is located outside the housing, and the visible light emitted by the visible light source can pass through the light-transmitting window on the housing and illuminate the contact area between the two friction pairs; An infrared light source is located outside the housing. The infrared light emitted by the infrared light source can pass through the light-transmitting window on the housing and illuminate the contact area between the two friction pairs. The visible light and the infrared light overlap in time and space to form a sum-frequency spectrum.

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