A visual imaging oil wear debris in-situ detection device and system

Abstract

The present invention relates to the field of oil monitoring technology, and discloses a visual imaging oil wear debris in-situ detection device and system. A translucent tempered glass slide is attached to the inner wall of a flow channel, a guide column is placed in the inner cavity of the flow channel, and an approximately annular oil cavity is formed between the guide column and the translucent tempered glass slide. The guide column diverts the oil entering the flow channel so that it enters the oil cavity; a magnet is connected to an excitation coil and embedded in the flow channel and adheres to the outer surface of the translucent tempered glass slide; power is applied to the excitation coil to generate a magnetic field in the air gap between the N pole and the S pole of the magnet, so that the metal wear debris in the oil in the oil cavity is adsorbed in the air gap between the translucent tempered glass slide and the magnet; light is radiated by a light source to illuminate the wear debris, so that the reflected light on the wear debris surface is imaged on the photosensitive surface of the imaging device through an optical lens, forming a wear debris image, and the wear debris image is used to perform in-situ detection of oil wear debris, thereby improving the detection efficiency of oil wear debris.

Description

Technical Field

[0001] The present invention relates to the technical field of oil monitoring, and in particular to a visual imaging oil wear debris in-situ detection device and system. Background Art

[0002] With the continuous development and application of high-end equipment, improving the level of condition-based maintenance technology has become an urgent need. Oil wear debris monitoring technology is a key tool for equipment fault diagnosis and maintenance. It can extract wear debris characteristic parameter information from the oil in the equipment lubrication system, reflecting equipment wear and failure caused by aging or damage of components. This enables equipment operating status monitoring and fault warning, thereby reducing equipment operation and maintenance costs.

[0003] Oil wear debris sensors can be categorized as non-image-based and image-based sensors based on their sensing method. Non-image-based wear debris sensors (such as those based on resistance, electromagnetic induction, electrostatic induction, photoelectric, and ultrasonic principles) that detect various electrical parameters are characterized by high sensitivity and fast detection speed. They can be used for online wear debris monitoring to determine wear debris mass concentration and material properties. However, their poor interference resistance under harsh operating conditions such as vibration and bubbles results in low reliability in oil wear debris detection and an inability to detect the geometric information of wear debris in the oil. Image-based oil wear debris sensing technology, on the other hand, can obtain wear debris image information. By extracting the size, concentration, particle size, morphology, and color characteristics of metal wear debris in the equipment's lubricating oil, it can characterize wear and tear, enabling real-time monitoring of equipment operating status and diagnosis of wear faults. In contrast, image-based oil wear debris sensors can enhance the anti-drying capability of oil wear debris detection and improve the accuracy of equipment wear status monitoring and fault diagnosis. They have become a key driver of the development of online oil wear debris monitoring technology. However, visual oil wear debris sensors are difficult to miniaturize and apply online. In addition, the optical microscope imaging components have limited depth of field and are sensitive to oil transmittance, making their research and design difficult.

[0004] In order to solve the above technical problems, patent CN200610041773.X discloses a small-volume online image visual iron spectrum probe, which can achieve orderly deposition of large and small wear chips in the collection area and can collect wear chip deposition spectrum image information; patents CN201310141313.4 and CN201610052551.1 propose an online wear chip monitoring probe based on video image acquisition, which extracts visual feature information of metal particles in oil through video monitoring, realizing online monitoring of mechanical wear status and real-time judgment of oxidative wear status; patent CN201410206588.6 discloses a full-field microscopic imaging oil wear chip detection device. Compared with patent CN200610041773.X, it increases the field of view of the wear chip image and can use bright field imaging under reflected light to extract the amount of wear chip visual feature information, thereby improving the accuracy of the judgment of online monitoring results of equipment wear. However, the image-visual oil wear debris detection device described in the aforementioned patent can only be used in translucent oil conditions. For low-transmittance or opaque oils, effective image acquisition of wear debris information is impossible. Furthermore, the oil chamber height in these conditions is less than 1mm, resulting in low oil flow and low detection efficiency. To address this, patent CN201610976289.X and a journal article (A panoramic ferrograph for on-site detection of oil wear debris) propose a dark-field imaging oil wear debris detection device. This device adsorbs metal wear debris in the oil onto a transparent window surface above the oil layer, preventing interference from oil transmittance and bubbles on wear debris image acquisition. This enables visual acquisition and analysis of oil wear debris in low-transmittance or even black oil conditions. Patents CN202310470547.7, CN202110680718.X, CN201820860711.X, and CN201820860695.4 utilize the full-field microscopic imaging oil wear debris detection device disclosed in patent CN201410206588.6 to develop an online wear monitoring device. Patent CN201820861129.5 utilizes the online image visual ferrography reflected light imaging device disclosed in patent CN201610976289.X to develop a reflective online visual ferrography monitoring system, aiming to implement online monitoring of wear oil and wear debris in industrial field equipment. However, the oil flow path structural design of the devices proposed in patents CN201610976289.X and CN201410206588.6 has inherent defects, and the cross-sectional area of ​​the oil cavity is approximately 5mm. 2 , resulting in an oil flow rate of less than 5ml / min. Under this condition, it is impractical to install it in the equipment lubrication oil circuit for online oil wear debris detection. Therefore, the current oil wear debris monitoring device still has the problem of a small oil cavity, resulting in a small oil flow rate, which is not conducive to oil wear debris detection. Summary of the Invention

[0005] The purpose of the present invention is to provide a visual imaging in-situ detection device and system for oil wear debris, which can effectively improve the detection efficiency of oil wear debris.

[0006] To solve the above technical problems, an embodiment of the present invention provides a visual imaging in-situ detection device for oil wear debris, comprising:

[0007] A translucent tempered glass sheet is fixed to the inner wall of the flow channel. An oil inlet and outlet pipe joints are installed at both ends of the flow channel. The bottom end of the guide column is embedded in the outlet pipe joint and placed in the inner cavity of the flow channel, so that an annular oil cavity is formed between the guide column and the translucent tempered glass sheet. After the oil flows into the flow channel through the oil inlet pipe joint, the guide column diverts the oil, allowing the oil to enter the oil cavity to generate oil circulation and flow out through the oil outlet pipe joint.

[0008] The excitation module consists of two rectangular cores, four cylindrical cores, four excitation coils, and four pairs of magnets. The four cylindrical cores are clamped and fixed at four right-angled ends between the two parallel rectangular cores. The four excitation coils are wound around the four cylindrical cores, and the four pairs of magnets are installed and fixed on the inner sides of the two parallel rectangular cores. By energizing each excitation coil, a pulsating magnetic field is generated in the air gap between the north and south poles of each pair of magnets. The magnetic field force of the pulsating magnetic field attracts metal debris in the oil inside the oil chamber to the inner surface of the transparent tempered glass slide, forming deposited debris in the air gap between the north and south poles of the magnets.

[0009] The visualization imaging module is placed in a rectangular space surrounded by two excitation coils and two rectangular iron cores, and is perpendicular to the corresponding excitation coils; the visualization imaging module is fixedly connected to the flow channel, and includes an optical lens and an imaging device. By radiating light to the translucent tempered glass slide, the deposited wear debris formed on the inner surface of the translucent tempered glass slide is illuminated, so that the radiated light is imaged on the photosensitive surface of the imaging device through the optical lens, forming an image of the deposited wear debris, so as to perform in-situ detection of oil wear debris through the deposited wear debris image.

[0010] In some optional embodiments, a planar transmission light source is provided on the surface of the guide column, and a light guide reflector is also sealed and fixed thereto; wherein a wire through hole is processed inside the guide column for arranging the power wires of the planar transmission light source;

[0011] The plane transmitted light source is used to radiate light, and the light is projected onto the transparent tempered glass slide between the N pole and the S pole of the magnet through the light guide reflector, thereby illuminating the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide with transmitted light.

[0012] In some optional embodiments, the visualization imaging module further includes a reflective light source, the radiation light of which is projected onto the transparent tempered glass slide between the N pole and the S pole of the magnet, thereby reflecting the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide.

[0013] In some optional embodiments, if the optical magnification of the optical lens is 1.0×~3.0× and the oil attenuation coefficient of the oil is less than 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector, and the contrast perspective ratio used to characterize the contrast of the deposited wear debris image under different oil attenuation coefficients is less than 0, and light is radiated through a plane transmitted light source or a reflected light source to perform transmitted light illumination or reflected light illumination on the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide and located in the air gap between the N pole and the S pole of the magnet;

[0014] If the optical magnification of the optical lens is 1.0× to 3.0×, and the oil attenuation coefficient of the oil is greater than or equal to 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector, and the contrast perspective ratio is greater than or equal to 0, the light source is radiated by the reflected light source to illuminate the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide and located in the air gap between the north pole and the south pole of the magnet;

[0015] Among them, the contrast perspective ratio is the ratio of the difference between the reflected irradiance and the diffuse reflected irradiance to the total irradiance of the photosensitive surface of the image device, and the total irradiance is the sum of the reflected irradiance, the diffuse reflected irradiance and the backscattered irradiance of the photosensitive surface of the image device.

[0016] In some optional embodiments, the optical lens is provided with an adjusting screw sleeve, and the optical magnification of the optical lens is adjusted by rotating the adjusting screw sleeve.

[0017] In some optional embodiments, there are four visualization imaging modules, each visualization imaging module is placed in a rectangular space surrounded by two adjacent excitation coils and two rectangular iron cores, and the angle between two adjacent visualization imaging modules is 90°.

[0018] In some optional embodiments, the device further includes a mounting seat, a lens screw sleeve is provided on the visualization imaging module, and the visualization imaging module is embedded into the internal space of the mounting seat through the threads on the lens screw sleeve.

[0019] In some optional embodiments, the height of the oil chamber is 0.5 mm to 5 mm.

[0020] In some optional embodiments, the width of the air gap between the north pole and the south pole of the magnet is 0.5 mm to 5 mm.

[0021] An embodiment of the present invention further provides a visual imaging in-situ oil wear debris detection system, comprising:

[0022] Computer equipment with wireless communication capabilities, wireless networks via Ethernet / 4G / 5G communication, wireless communication modules, microcontroller units, pumps, solenoid valves, and the above-mentioned visual imaging oil wear debris in-situ detection device;

[0023] The computer device sends a control instruction for instructing in-situ detection of oil wear debris. The control instruction is transmitted to the wireless communication module via a wireless network. The wireless communication module converts the control instruction into a signal and sends it to the microcontroller unit.

[0024] The microcontroller unit controls the pump and the solenoid valve to open, allowing the oil to flow into the flow channel through the oil inlet pipe joint. The guide column then diverts the oil, allowing the oil to enter the oil chamber to generate oil circulation. The microcontroller unit controls the power supply of each excitation coil to generate a pulsating magnetic field in the air gap between the north pole and south pole of each pair of magnets. The magnetic field force of the pulsating magnetic field adsorbs the metal debris in the oil in the oil chamber onto the inner surface of the transparent tempered glass slide, forming deposited debris in the air gap between the two magnetic poles of the magnet. The reflective light source of the visualization imaging module is controlled to illuminate the deposited debris adsorbed on the inner surface of the transparent tempered glass slide, so that the reflected light from the surface of the deposited debris is imaged on the photosensitive surface of the imaging device through the optical lens, forming an image of the deposited debris.

[0025] The visualization imaging module is also used to transmit the obtained deposited wear debris image to the computer device through the wireless communication module and the wireless network. The computer device processes and analyzes the deposited wear debris image to complete the in-situ detection of oil wear debris.

[0026] The visual imaging in-situ oil wear debris detection device provided by the present invention has the following beneficial effects:

[0027] Due to the limited depth of field of the existing image visualization oil wear debris sensor microscopic imaging system, in order to obtain a clear wear debris image, the height of the oil cavity in the flow channel of the image visualization wear debris sensor is mostly between 50 and 1000 μm. The narrow oil cavity and low oil flow rate will limit the oil flow rate of the image visualization wear debris sensor, affecting the efficiency of online monitoring of oil wear debris. The present invention mounts a transparent tempered glass slide on the inner wall of the flow channel, and sets a guide column in the inner cavity of the flow channel, so that a nearly annular oil cavity is formed between the guide column and the transparent tempered glass slide. After the oil flows into the flow channel, the oil is diverted by the guide column, so that the oil flows close to the approximately annular oil cavity at the edge of the flow channel. Compared with the traditional oil cavity, it can increase the oil flow rate of the flow channel of the image visualization oil wear debris sensor without affecting the microscopic imaging effect of the oil wear debris, thereby effectively improving the detection efficiency of oil wear debris. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] One or more embodiments are exemplarily described by the figures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments.

[0029] Figure 1 1 is a schematic structural diagram of a visual imaging in-situ detection device for oil wear debris provided according to an embodiment of the present invention;

[0030] Figure 2 is a structural schematic diagram of an excitation module provided according to an embodiment of the present invention;

[0031] Figure 3 is a structural diagram of a visual imaging module provided according to an embodiment of the present invention;

[0032] Figure 4 1 is a schematic diagram of a decoupling strand of a guide column provided according to an embodiment of the present invention;

[0033] Figure 5 is a flow chart of a visual imaging method for oil wear debris detection provided according to one embodiment of the present invention;

[0034] Figure 6 (a) is a spectrum of deposited wear debris of gearbox oil in reflected light and transmitted light provided according to one embodiment of the present invention;

[0035] Figure 6 (b) is a spectrum of deposited wear debris of gasoline engine oil in reflected light and transmitted light provided according to one embodiment of the present invention;

[0036] Figure 6 (c) is a spectrum of deposited wear debris of diesel engine oil in reflected light and transmitted light provided according to one embodiment of the present invention;

[0037] Figure 7 1 is a schematic structural diagram of a visual imaging oil wear debris in-situ detection system provided according to an embodiment of the present invention;

[0038] Among them, the flow channel 1; the guide column 2; the excitation module 3; the visualization imaging module 4; the translucent tempered glass slide 5; the oil chamber 6; the mounting seat 7; the oil inlet pipe joint 8; the oil outlet pipe joint 9; the computer 10; the wireless network 11; the wireless communication module 12; the micro control unit 13; the pump 14; the solenoid valve 15; the planar transmission light source 21; the light guide reflector 22; the wire through hole 23; the rectangular iron core 31; the cylindrical iron core 32; the excitation coil 33; the magnet 34; the optical lens 41; the imaging device 42; the reflective light source 43; the adjusting screw sleeve 44; and the lens screw sleeve 45. DETAILED DESCRIPTION

[0039] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be understood by those skilled in the art that in the embodiments of the present invention, many technical details are provided to help readers better understand the present invention. However, even without these technical details and the various changes and modifications based on the following embodiments, the technical solutions claimed in the present invention can be implemented. The division of the following embodiments is for convenience of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with each other and referenced to each other under the premise that there is no contradiction.

[0040] One embodiment of the present invention relates to a visual imaging in-situ detection device for oil wear debris. The implementation details of the visual imaging in-situ detection device for oil wear debris of this embodiment are described in detail below. The following content is only the implementation details provided for the convenience of understanding and is not necessary for the implementation of this solution.

[0041] The specific structure of the visual imaging oil wear debris in-situ detection device of this embodiment is as follows: Figure 1 As shown, it includes a flow channel 1, a guide column 2, an excitation module 3 and a visualization imaging module 4.

[0042] A light-transmitting tempered glass sheet 5 is mounted and fixed to the inner wall of the flow channel 1. An oil inlet pipe joint 8 and an oil outlet pipe joint 9 are installed at both ends of the flow channel 1. The bottom end of the guide column 2 is embedded in the oil outlet pipe joint 9 and is placed in the inner cavity of the flow channel 1, so that a nearly annular oil cavity 6 is formed between the guide column 2 and the light-transmitting tempered glass sheet 5. The height of the oil cavity 6 can be 0.5mm to 5mm. Therefore, after the oil flows into the flow channel 1 through the oil inlet pipe joint 8 of the flow channel 1, the oil can be diverted by the guide column 2, so that the oil enters the oil cavity 6 to generate oil circulation, and then flows out of the flow channel 1 through the oil outlets on both sides of the oil outlet pipe joint 9 of the flow channel 1.

[0043] The specific structure of the excitation module 3 is as follows Figure 2As shown, it consists of two rectangular cores 31, four cylindrical cores 32, four excitation coils 33, and four pairs of magnets 34. The four cylindrical cores 32 are clamped and fixed at four right-angled ends between the two parallel rectangular cores 31. The four excitation coils 33 are wound around the four cylindrical cores 32. The four pairs of magnets 34 are mounted and fixed inside the two parallel rectangular cores 31, and the two pairs can be tightly fitted to reduce magnetic leakage. The magnets 34 include two magnetic poles (i.e., an north pole and a south pole), with an air gap between the north and south poles. The air gap width can be 0.5 mm to 5 mm. Therefore, by energizing each excitation coil 33, a high-gradient pulsating magnetic field can be generated in the air gap between the N pole and the S pole of each pair of magnets 34. The magnetic field force of the high-gradient pulsating magnetic field can adsorb the metal debris in the oil inside the oil chamber 6 onto the inner surface of the transparent tempered glass slide 5, so as to form deposited debris in the air gap between the N pole and the S pole of the magnet 34.

[0044] The specific structure of the visualization imaging module 4 is as follows Figure 3 As shown, it is placed in a rectangular space enclosed by two excitation coils 33 and two rectangular iron cores 31, and is perpendicular to the corresponding excitation coils 33. The visualization imaging module 4 is fixedly connected to the flow channel 1 and includes an optical lens 41 and an imaging device 42. Therefore, by radiating light toward the transparent tempered glass slide 5, the deposited wear debris formed on the inner surface of the transparent tempered glass slide 5 is illuminated. The radiated light is imaged by the optical lens 41 onto the photosensitive surface of the imaging device 42, forming an image of the deposited wear debris. This allows for in-situ detection of oil wear debris through deposited wear debris image processing and analysis.

[0045] In this embodiment, due to the limited depth of field of the existing image visualization oil wear debris sensor microscopic imaging system, in order to obtain a clear wear debris image, the height of the oil cavity in the flow channel of the image visualization wear debris sensor is mostly between 50 and 1000 μm. The narrow oil cavity and low oil flow rate will limit the oil flow rate of the image visualization wear debris sensor, affecting the efficiency of online monitoring of oil wear debris. In this embodiment, a transparent tempered glass slide is mounted on the inner wall of the flow channel, and a guide column is set in the inner cavity of the flow channel, so that a nearly annular oil cavity is formed between the guide column and the transparent tempered glass slide. After the oil flows into the flow channel, the oil is diverted by the guide column, so that the oil flows in the approximately annular oil cavity close to the edge of the flow channel. Compared with the traditional oil cavity, the oil flow rate of the flow channel of the image visualization oil wear debris sensor can be improved without affecting the microscopic imaging effect of oil wear debris.

[0046] In some embodiments, there is at least one and at most four visualization imaging modules 4. Each visualization imaging module 4 is placed within a rectangular space enclosed by two adjacent excitation coils 33 and two rectangular iron cores 31, and the angle between two adjacent visualization imaging modules 4 is 90°. Since visualization imaging module 4 is used to obtain images of deposited wear debris in the present invention, providing multiple visualization imaging modules 4 can effectively improve the efficiency of monitoring metal wear debris in oil.

[0047] In one example, the visual imaging oil wear debris in-situ detection device of this embodiment also includes a mounting seat 7, a lens screw sleeve 45 is provided on the visual imaging module 4, and the visual imaging module 4 is embedded in the internal space of the mounting seat 7 through the threads on the lens screw sleeve 45.

[0048] In some embodiments, the specific structure of the guide column 2 of the present invention is as follows Figure 4 As shown, a planar transmissive light source 21 is disposed on the surface of the guide column 2, and a light guide reflector 22 is also sealed and fixed thereto. A wire through-hole 23 is machined inside the guide column 2 for accommodating the energized wires of the planar transmissive light source 21. Therefore, in this embodiment, the planar transmissive light source 21 can generate the light radiated toward the transparent tempered glass slide 5. The light radiated by the planar transmissive light source 21 is then projected through the light guide reflector 22 onto the transparent tempered glass slide 5 between the north and south poles of the magnet 34, thereby illuminating the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide 5 with transmitted light, forming an image of the deposited wear debris.

[0049] In other embodiments, the visualization imaging module 4 further includes a reflective light source 43. Therefore, in this embodiment, the reflective light source 43 can be used to generate the light radiated toward the transparent tempered glass slide 5. In this case, the light radiated by the reflective light source 43 is projected onto the transparent tempered glass slide 5 between the north and south poles of the magnet 34, thereby reflecting the accumulated wear debris adsorbed on the inner surface of the transparent tempered glass slide 5. Furthermore, in this case, the light radiated by the reflective light source 43 is reflected by the light guide reflector 22 and enters the optical lens 41, forming a background image of the accumulated wear debris on the photosensitive surface of the imaging device 42.

[0050] In a specific implementation, if the optical magnification of the optical lens 41 is 1.0× to 3.0× and the oil attenuation coefficient of the oil is less than 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector 22, and the contrast perspective ratio used to characterize the contrast of the deposited wear debris image under different oil attenuation coefficients is less than 0. Light is radiated through the plane transmitted light source 21 or the reflected light source 43 to illuminate the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide 5 and located in the air gap between the N pole and the S pole of the magnet 34 with transmitted light or reflected light;

[0051] If the optical magnification of the optical lens 41 is 1.0× to 3.0× (e.g., 2.2×), and the oil attenuation coefficient of the oil is greater than or equal to 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector 22, and the contrast perspective ratio is greater than or equal to 0. The reflected light source 43 radiates light to reflect the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide 5 and located in the air gap between the N pole and the S pole of the magnet 34.

[0052] The contrast perspective ratio is the ratio of the difference between the reflected irradiance and the diffuse reflected irradiance to the total irradiance of the photosensitive surface of the image device 42 . The total irradiance is the sum of the reflected irradiance, the diffuse reflected irradiance and the backscattered irradiance of the photosensitive surface of the image device 42 .

[0053] An adjusting screw sleeve 44 is provided on the optical lens 41 , and the optical magnification of the optical lens 41 can be adjusted by rotating the adjusting screw sleeve 44 .

[0054] It can be seen that the present invention provides two solutions for radiating light toward the light-transmitting tempered glass slide 5 , and provides two solutions for forming deposited wear debris images according to the optical magnification of the optical lens 41 used.

[0055] Based on this, the present invention also provides two methods for forming deposited wear debris images (i.e., high-throughput visualization imaging methods for oil wear debris detection) to enable online acquisition of deposited wear debris images. The visualization imaging methods of this embodiment are then used to verify the two methods for forming deposited wear debris images. Specifically, the present invention uses a high-throughput visualization imaging method for in-situ oil wear debris detection to determine which high-throughput visualization imaging method is appropriate for oil wear debris detection when using oils with different attenuation coefficients, assuming the optical magnification of the optical lens 41 of the visualization imaging module 4 is 2.2×.

[0056] The principle adopted is as follows: calculate the reflected irradiance of the deposited wear debris image surface received by the photosensitive surface of the image device 42 in the visualization imaging module 4, the diffuse reflected irradiance of the lower surface of the light guide reflector 22, and the backscattered irradiance of the oil in the oil chamber 6, that is, the backscattered irradiance of the photosensitive surface of the image device 42, and then use the contrast perspective ratio to quantitatively describe the contrast of the visualized wear debris image under different oil attenuation coefficients, establish a reflected light imaging contrast perspective ratio model based on linear superposition of irradiance, and finally, under the condition of an optical magnification of 2.2×, simulate and calculate the numerical relationship between the oil attenuation coefficient and the contrast perspective ratio, and determine the visualization imaging method for oil wear debris detection according to the variation range of the oil attenuation coefficient and the contrast perspective ratio. The specific implementation steps are as follows: Figure 5 As shown, including:

[0057] S1: Assuming that the deposited wear debris is in close contact with the transparent tempered glass 5, the surface of the deposited wear debris under reflected light is regarded as a Lambertian cosine body with the same reflectivity, thereby deducing the photosensitive surface of the image device 42 ( x',y' ) coordinate point reflected irradiance of the deposited wear debris for:

[0058] ;

[0059] Where, θ 1 is the angle between the radiation light and the normal line on the surface of deposited wear debris, ω 1 is the angle between the refraction angle of the light after it enters the air and the principal optical axis, D 0 is the object-side entrance pupil diameter of the optical lens 41, τ 0 is the transmittance of the optical lens 41, ρ n is the reflectance of the deposited wear debris, R T is the reflectivity of the light-transmitting tempered glass 5, that is , and are the refractive indices of the light-transmitting tempered glass 5 and air, f is the effective focal length of the optical lens 41, β is the optical magnification of the optical lens 41, I0 is the luminous intensity in the direction of the main optical axis of the optical lens 41, H is the distance between the reflecting light source 43 and the deposition interface of the deposited wear debris, is the effective radius of the annular reflective light source 43 .

[0060] S2: Divide the lower surface of the light guide reflector 22 into several micro-elements, and each micro-element is regarded as a Lambert cosine body with uniform irradiance. When the oil cavity is filled with oil, any Lambert cosine body micro-element dS The radiation light will pass through the light guide reflector 22, the oil layer and the light-transmitting tempered glass 5 and enter the entrance pupil of the optical lens 41. Assuming that the entrance pupil of the optical lens 41 coincides with the object side principal plane, the microelement coordinates of the lower surface of the light guide reflector 22 are represented by the image plane coordinates and the optical magnification. dS The optical lens 41 forms a micro-element image on the photosensitive surface of the image device 42. dS' , it can be deduced that the photosensitive surface of the image device 42 ( x’ , y’ ) The diffuse reflection irradiance of the light guide reflector 22 at the coordinate point for:

[0061] ;

[0062] Where, θ 2 is a microelement dS The angle of incidence of the radiation light, refracted by the quartz window-air interface, ω 3 is the angle between the center of the entrance pupil of the optical lens 41 and the main optical axis, c 1 is the height of the oil cavity 6 between the light-transmitting tempered glass 5 and the light-guiding reflective plate 22, c 2 and c 3 are the thicknesses of the light-transmitting tempered glass 5 and the light-guiding reflective plate 22, respectively. ρ b is the optical reflection coefficient of the surface of the light guide reflector 223, α is the incident angle of the radiation from the reflected light source 43, and γ is the refraction angle of the radiation light entering the upper transparent tempered glass 5 from the air. The refractive indexes of the transparent tempered glass 5, the light guide reflector 22 and the oil are similar, and the difference is ignored. Then we have γ Identical to arcsin(n air sinα / n gls )，C 0 is the oil attenuation coefficient, E 0( x',y' ) is the irradiance distribution of the reflected light source 43 received on the surface of the light guide reflector 22.

[0063] S3: The thickness of the oil cavity 6 is c 1 The oil layer is divided into rectangular micro-elements of equal thickness. All micro-elements are parallel to the photosensitive surface of the image device 42. Considering the light energy loss of the radiation light of the reflected light source 43 absorbed by the oil layer, the backscattered irradiance received by the photosensitive surface of the image device 42 can be deduced. for:

[0064] ;

[0065] S4: Total irradiance received by the photosensitive surface of the image device 42 Can be regarded as the reflected irradiance of deposited wear debris , diffuse reflection irradiance of the light guide reflector 22 and oil backscattered irradiance The linear superposition of the contrast perspective C R ( x',y' ) is described as With total irradiance The ratio of , then:

[0066] .

[0067] (1) In optical magnification β =2.2× and C 0 <2.0, the simulation calculation can be obtained , contrast perspective ratio of visualization imaging C R ( x',y' )<0, at this time, the oil wear debris in-situ detection device with large-throughput visual imaging can use the reflected light source 43 and the planar transmitted light source 21 to perform online monitoring of oil wear debris, and can detect the deposited wear debris images of the transmitted light and the reflected light;

[0068] (2) In optical magnification β =2.2× and C 0 Under the condition of ≥2.0, simulation calculation can be obtained , contrast perspective ratio of visualization imaging C R ( x',y' )≥0, at this time, the oil wear debris in-situ detection device with large-throughput visual imaging can use the reflected light source 43 to perform online monitoring of oil wear debris, and can detect the deposited wear debris image of the reflected light.

[0069] In one example, the present invention used a visual imaging oil wear debris in-situ detection device to carry out an online oil wear debris image acquisition experiment, detecting metal wear debris in gearbox oil, gasoline engine oil, and diesel engine oil with oil attenuation coefficients of approximately 1.15, 2.28, and 3.86, respectively. The experimental results are shown in Figure 6 .

[0070] When the oil attenuation coefficient is 1.15 (1 ± 0.3%), diffuse reflected light can pass through the oil layer, forming a bright background on the photosensitive surface of the imaging device 42, thus achieving bright field imaging of wear debris. The black wear debris image in the reflected light wear debris spectrum is clearly distinguishable, and some wear debris produces reflections. The wear debris identification degree of the projection imaging in the transmission spectrum is relatively high, such as Figure 6 As shown in (a); when the oil attenuation coefficient is 2.28 (1±0.3%), the diffuse reflected light is absorbed and consumed in the oil layer, resulting in a decrease in the contrast perspective ratio of the photosensitive surface of the image device 42, causing the contrast between the background and the wear debris image in the reflected light wear debris spectrum to decrease, making it more difficult to identify the wear debris image, and the contrast between the background and the wear debris image in the transmitted light spectrum to decrease sharply, making it impossible to effectively identify the wear debris image, as shown in Figure 2. Figure 6As shown in (b); when the oil attenuation coefficient is 3.86 (1 ± 0.3%), the energy of diffuse reflected light and backscattered light is largely absorbed, resulting in enhanced image contrast between the wear debris and the black background. The recognition of large wear debris and wear debris chains in the reflected light wear debris spectrum is high, and dark field imaging of wear debris is achieved. However, due to the extremely low light transmittance of the oil, the intensity of the transmitted light received by the photosensitive surface of the imaging device 42 is less than its photosensitivity. The image contrast between the wear debris and the background in the transmitted light wear debris spectrum is zero. At this time, the transmitted light wear debris detection fails, as shown in FIG. Figure 6 As shown in (c) in .

[0071] In summary, the visualization imaging method and detection performance of the in-situ detection device for oil wear debris of the present invention were tested through experiments on online acquisition of reflected light and transmitted light wear debris images. The experimental results show that when the oil attenuation coefficient is less than 2.0, the present invention can effectively obtain visual information of wear debris in bright field imaging from translucent oil, and the greater the oil attenuation coefficient, the more blurred the wear debris image in the reflected light wear debris spectrum; when the oil attenuation coefficient is greater than 2.0, the present invention can effectively obtain visual information of wear debris in dark field imaging from low-transmittance and opaque oil, and the greater the oil attenuation coefficient, the clearer the wear debris image in the reflected light wear debris spectrum, and the best wear debris imaging quality can be obtained in the central field of view area of ​​the spectrum. The present invention has engineering significance and application value for detecting metal wear debris in oil using the principle of optical imaging and realizing intelligent monitoring of mechanical transmission systems of major equipment.

[0072] One embodiment of the present invention relates to a visual imaging in-situ detection system for oil wear debris. The implementation details of the visual imaging in-situ detection system for oil wear debris of this embodiment are described in detail below. The following content is only the implementation details provided for the convenience of understanding and is not necessary for the implementation of this solution.

[0073] The specific structure of the visual imaging oil wear debris in-situ detection system of this embodiment is as follows: Figure 7 As shown, it includes: a computer device 10 with wireless communication function, a wireless network 11 via Ethernet / 4G / 5G communication, a wireless communication module 12, a micro control unit 13, a pump 14, a solenoid valve 15 and an in-situ detection device for oil wear debris with visual imaging as described in any of the above embodiments.

[0074] The working principle of the visual imaging oil wear debris in-situ detection system of this embodiment is as follows:

[0075] The computer device 10 sends a control instruction for instructing in-situ detection of oil wear debris. The control instruction is transmitted to the wireless communication module 12 via the wireless network 11. The wireless communication module 12 converts the control instruction into a signal and sends it to the micro control unit 13.

[0076] The microcontrol unit 13 controls the pump 14 and the solenoid valve 15 to open, so that the oil flows into the flow channel 1 through the oil inlet pipe joint 8. The guide column 2 then diverts the oil and allows the oil to enter the oil chamber 6 to generate oil circulation. The microcontroller 13 controls each excitation coil 33 to be energized, so that a pulsating magnetic field is generated in the air gap between the N pole and the S pole of each pair of magnets 34. The magnetic field force of the pulsating magnetic field adsorbs the metal debris in the oil in the oil chamber 6 onto the inner surface of the transparent tempered glass slide 5, forming deposited debris in the air gap between the two magnetic poles of the magnet 34. The reflective light source 43 of the visualization imaging module 4 is controlled to illuminate the deposited debris adsorbed on the inner surface of the transparent tempered glass slide 5, so that the reflected light from the surface of the deposited debris is imaged on the photosensitive surface of the imaging device 42 through the optical lens 41, forming an image of the deposited debris.

[0077] The visualization imaging module 4 is also used to transmit the obtained deposited wear debris image to the computer device 10 through the wireless communication module 12 and the wireless network 11. The computer device 10 processes and analyzes the deposited wear debris image to complete the in-situ detection of oil wear debris.

[0078] In this embodiment, a computer equipped with wireless communication capabilities directly communicates with a wireless communication module for wireless data transmission, enabling online detection of wear debris from mechanical equipment within an industrial field local area network. Compared to conventional technologies, this invention not only enables online detection of wear debris using visual imaging, but also improves detection capabilities by more than four times.

[0079] Those skilled in the art will appreciate that the above-described embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes in form and detail may be made thereto without departing from the spirit and scope of the embodiments of the present invention. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, the scope of protection of the embodiments of the present invention shall be subject to the scope defined in the claims.

Claims

1. A visual imaging in-situ detection device for oil wear debris, characterized in that: include: A flow channel (1), a guide column (2), an excitation module (3), and a visualization imaging module (4); A light-transmitting tempered glass sheet (5) is fixedly mounted on the inner wall of the flow channel (1), and an oil inlet pipe joint (8) and an oil outlet pipe joint (9) are respectively mounted on both ends of the flow channel (1). The bottom end of the guide column (2) is embedded in the oil outlet pipe joint (9) and is arranged in the inner cavity of the flow channel (1), so that an annular oil cavity (6) is formed between the guide column (2) and the light-transmitting tempered glass sheet (5); after the oil flows into the flow channel (1) through the oil inlet pipe joint (8), the guide column (2) diverts the oil, so that the oil enters the oil cavity (6) to generate oil circulation, and flows out through the oil outlet pipe joint (9); The excitation module (3) is composed of two rectangular iron cores (31), four cylindrical iron cores (32), four excitation coils (33) and four pairs of magnets (34). The four cylindrical iron cores (32) are clamped and fixed at four right-angled ends between the two parallel rectangular iron cores (31). The four excitation coils (33) are respectively wound on the four cylindrical iron cores (32). The four pairs of magnets (34) are installed and fixed on the inner sides of the two parallel rectangular iron cores (31). By energizing each excitation coil (33), a pulsating magnetic field is generated in the air gap between the N pole and the S pole of each pair of magnets (34). The magnetic field force of the pulsating magnetic field adsorbs the metal grinding debris in the oil liquid inside the oil cavity (6) onto the inner surface of the transparent tempered glass slide (5), so as to form deposited grinding debris in the air gap between the N pole and the S pole of the magnet (34). The visualization imaging module (4) is placed in a rectangular space surrounded by two excitation coils (33) and two rectangular iron cores (31), and is perpendicular to the corresponding excitation coils (33); the visualization imaging module (4) is fixedly connected to the flow channel (1), and includes an optical lens (41) and an imaging device (42). By radiating light toward the translucent tempered glass slide (5), the deposited wear debris formed on the inner surface of the translucent tempered glass slide (5) is illuminated, so that the radiated light is imaged on the photosensitive surface of the imaging device (42) through the optical lens (41), forming an image of the deposited wear debris, so that the oil wear debris is detected in situ through the deposited wear debris image; A planar transmission light source (21) is provided on the surface of the guide column (2), and a light guide reflector (22) is also sealed and fixed thereto; a wire through hole (23) is machined inside the guide column (2) for arranging the power conducting wires of the planar transmission light source (21); The plane transmission light source (21) is used to radiate light, and the light is projected onto the light-transmitting tempered glass slide (5) between the N pole and the S pole of the magnet (34) through the light guide reflector (22), so as to illuminate the deposited grinding debris adsorbed on the inner surface of the light-transmitting tempered glass slide (5) with transmitted light; The visualization imaging module (4) further includes a reflective light source (43), wherein radiation light from the reflective light source (43) is projected onto the light-transmitting tempered glass slide (5) between the N pole and the S pole of the magnet (34), thereby reflecting light to illuminate the deposited wear debris adsorbed on the inner surface of the light-transmitting tempered glass slide (5).

2. The visual imaging oil wear debris in-situ detection device according to claim 1 is characterized in that: If the optical magnification of the optical lens (41) is 1.0× to 3.0×, and the oil attenuation coefficient of the oil is less than 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector (22), and the contrast perspective ratio used to characterize the contrast of the deposited wear debris image under different oil attenuation coefficients is less than 0, and light is radiated through a plane transmitted light source (21) or a reflected light source (43) to illuminate the deposited wear debris adsorbed on the inner surface of the transparent tempered glass slide (5) and located in the air gap between the N pole and the S pole of the magnet (34) with transmitted light or reflected light; If the optical magnification of the optical lens (41) is 1.0× to 3.0×, and the oil attenuation coefficient of the oil is greater than or equal to 2.0, the reflected irradiance of the deposited wear debris image is less than the diffuse reflected irradiance of the lower surface of the light guide reflector (22), and the contrast perspective ratio is greater than or equal to 0, and the reflected light source (43) radiates light to illuminate the deposited wear debris adsorbed on the inner surface of the transparent tempered glass (5) and located in the air gap between the N pole and the S pole of the magnet (34); The contrast perspective ratio is the ratio of the difference between the reflected irradiance and the diffuse reflected irradiance to the total irradiance of the photosensitive surface of the image device (42), and the total irradiance is the sum of the reflected irradiance, the diffuse reflected irradiance and the backscattered irradiance of the photosensitive surface of the image device (42).

3. The visual imaging oil wear debris in-situ detection device according to claim 2, characterized in that: An adjusting screw sleeve (44) is provided on the optical lens (41), and the optical magnification of the optical lens (41) is adjusted by rotating the adjusting screw sleeve (44).

4. The visual imaging in-situ detection device for oil wear debris according to any one of claims 1 to 3, characterized in that: There are four visualization imaging modules (4), each visualization imaging module (4) is placed in a rectangular space surrounded by two adjacent excitation coils (33) and two rectangular iron cores (31), and the angle between two adjacent visualization imaging modules (4) is 90°.

5. The visual imaging oil wear debris in-situ detection device according to claim 1 is characterized in that: The device further comprises a mounting seat (7), a lens screw sleeve (45) is provided on the visualization imaging module (4), and the visualization imaging module (4) is embedded into the internal space of the mounting seat (7) through the threads on the lens screw sleeve (45).

6. The visual imaging oil wear debris in-situ detection device according to claim 1 is characterized in that: The height of the oil chamber (6) is 0.5 mm to 5 mm.

7. The visual imaging oil wear debris in-situ detection device according to claim 1 is characterized in that: The width of the air gap between the N pole and the S pole of the magnet (34) is 0.5 mm to 5 mm.

8. A visual imaging oil wear debris in-situ detection system, characterized by: The device comprises: a computer device (10) with wireless communication function, a wireless network (11) via Ethernet / 4G / 5G communication, a wireless communication module (12), a microcontroller unit (13), a pump (14), a solenoid valve (15), and an oil wear debris in-situ detection device with visualization imaging according to any one of claims 1 to 7; The computer device (10) sends a control instruction for instructing in-situ detection of oil wear debris, and the control instruction is transmitted to the wireless communication module (12) via the wireless network (11). The wireless communication module (12) converts the control instruction into a signal and sends it to the micro control unit (13); The microcontrol unit (13) controls the pump (14) and the electromagnetic valve (15) to open, so that the oil flows into the flow channel (1) through the oil inlet pipe joint (8), and then the guide column (2) diverts the oil so that the oil enters the oil chamber (6) to generate oil circulation and flows out through the oil outlet pipe joint (9); Controlling each excitation coil (33) to be energized, so that a pulsating magnetic field is generated in the air gap between the north pole and the south pole of each pair of magnets (34), and the magnetic field force of the pulsating magnetic field is used to adsorb metal grinding debris in the oil inside the oil chamber (6) onto the inner surface of the transparent tempered glass slide (5), so as to form deposited grinding debris in the air gap between the north pole and the south pole of the magnets (34); Controlling the reflective light source (43) of the visualization imaging module (4) to radiate light, and projecting the light onto the translucent tempered glass (5) between the N pole and the S pole of the magnet (34), or controlling the plane translucent light source (21) on the surface of the guide column (2) to radiate light, and projecting the light onto the translucent tempered glass (5) between the N pole and the S pole of the magnet (34) through the light guide reflector (22), illuminating the deposited wear debris adsorbed on the inner surface of the translucent tempered glass (5), so that the reflected light on the surface of the deposited wear debris is imaged on the photosensitive surface of the imaging device (42) through the optical lens (41), thereby forming an image of the deposited wear debris; The visualization imaging module (4) is also used to transmit the obtained deposited wear debris image to the computer device (10) through the wireless communication module (12) and the wireless network (11), and the computer device (10) processes and analyzes the deposited wear debris image to complete the in-situ detection of oil wear debris.

Images