Metal abrasive particle detection device based on radial magnetic field

Abstract

The utility model provides a metal abrasive particle detection device based on a radial magnetic field. The metal abrasive particle detection device comprises a sensing unit, a signal generation module, a signal processing module and a power supply module, the sensing unit comprises a cylindrical framework, a first excitation coil and a second excitation coil which are coaxially sleeved at two axial ends of the framework, and a first induction coil and a second induction coil which are symmetrically arranged at two circumferential sides of the middle part of the framework; the first baffle plate is coaxially sleeved on the framework and is used for clamping and fixing the first excitation coil and the second excitation coil respectively; the second baffle is arranged on the framework in a sleeving manner and is used for fixing a first induction coil and a second induction coil; and the runner is positioned in an induction area of the first induction coil and the second induction coil and penetrates through the framework. The two induction coils are vertically and symmetrically arranged on the radial plane of the centers of the two excitation coils, a high-strength radial magnetic field is generated in an induction area, the magnetization effect and the eddy current effect of metal abrasive particles are enhanced, and the abrasive particle detection sensitivity is remarkably improved.

Description

Technical Field

[0001] This utility model relates to the field of oil abrasive detection technology, specifically to a metal abrasive detection device based on a radial magnetic field. Background Technology

[0002] Mechanical wear is a common problem in various mechanical systems, and the size of the metal abrasive particles generated by wear is significantly positively correlated with the degree of wear. Metal abrasive particles generated by friction pairs in mechanical equipment continuously circulate in the lubricating oil, easily causing oil contamination and reducing lubrication efficiency. Furthermore, the presence of wear particles can lead to mechanical failures and pipe blockages, thereby impairing equipment performance and reducing its service life. By analyzing the size and material type of metal abrasive particles in the oil in real time, the wear condition of mechanical equipment can be assessed, providing early warnings before severe wear occurs. This not only improves the production efficiency of mechanical equipment but is also of great significance for ensuring the safe and stable operation of mechanical systems.

[0003] Oil wear particle detection methods are mainly divided into online and offline detection. Offline detection methods use instruments such as spectrometers and ferrometers for periodic sampling, resulting in lengthy testing cycles that cannot meet the needs of real-time monitoring. Furthermore, they require specialized analysts and incur high human and material costs. Online detection methods, on the other hand, overcome these shortcomings and mainly include optical, ultrasonic, capacitive, resistive, and inductive detection technologies. The most commonly used is inductive detection technology, which is based on the principle of electromagnetic induction. The disturbance of the magnetic field caused by metal wear particles leads to changes in coil parameters. By detecting these changes, the size, material, and other characteristic information of the metal wear particles can be reflected. Inductive detection technology has advantages such as compact structure, strong anti-interference ability, and insensitivity to oil quality; however, its sensitivity is currently relatively low and still needs continuous improvement.

[0004] The sensitivity of inductive abrasive particle detection is directly proportional to the magnetic field strength. To address this, existing technologies reduce the diameter of the excitation coil to generate a high-intensity axial magnetic field, thereby improving the sensitivity of abrasive particle detection. However, this approach inevitably limits the oil flow rate. Furthermore, adding silicon steel sheets, ferrite cores, or other high-permeability materials to inductive abrasive particle detection equipment can improve the axial magnetic field strength to some extent. However, due to the poor thermal stability of these materials, they are detrimental to improving the stability and sensitivity of abrasive particle detection in high-temperature or large-temperature-difference industrial environments, failing to meet practical application requirements. Utility Model Content

[0005] The purpose of this invention is to provide a metal abrasive particle detection device based on a radial magnetic field to overcome the shortcomings of the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A metal abrasive particle detection device based on a radial magnetic field includes a sensing unit, a signal generation module, a signal processing module, and a power supply module. The sensing unit includes a cylindrical frame, a first excitation coil and a second excitation coil coaxially sleeved at both ends of the frame, a first induction coil and a second induction coil symmetrically arranged on both sides of the middle of the frame, a first baffle coaxially sleeved on the frame for clamping and fixing the first excitation coil and the second excitation coil, a second baffle sleeved on the frame for fixing the first induction coil and the second induction coil, and a flow channel located in the sensing area of ​​the first induction coil and the second induction coil and penetrating the frame. The first excitation coil and the second excitation coil are wound close to the frame and the first baffle, and the second baffle is provided with protrusions for winding the first induction coil and the second induction coil.

[0008] Furthermore, the signal generation module includes a high-frequency signal generator and a power amplifier, used to generate a high-frequency sinusoidal excitation signal of 10kHz-1MHz, and to form a resonant circuit with the first excitation coil and the second excitation coil through a parallel excitation resonant capacitor; the first excitation coil and the second excitation coil are both ring coils and their winding directions are the same, and when energized, they can generate a uniform radial magnetic field in the central radial plane between them.

[0009] Furthermore, both the first and second induction coils are rectangular coils and their winding directions are opposite; the first and second induction coils are arranged vertically and symmetrically on both sides of the center plane of the radial magnetic field generated by the excitation coil; the first and second induction coils are connected in series with the induction resonant capacitor to form a resonant circuit, and the resonant frequency of the resonant circuit matches the frequency of the excitation signal; the output of the sensing unit is the differential induction signal of the first and second induction coils.

[0010] Furthermore, the signal processing module is used to receive the differential sensing signal output by the sensing unit and extract the wear particle characteristic signal, including a pre-differential amplifier circuit, a phase shifting circuit, a phase-sensitive detection circuit, a low-pass filter circuit, a post-amplifier circuit, and a signal acquisition circuit.

[0011] Furthermore, in the signal processing module, the pre-amplifier circuit amplifies the differential sensing signal output by the sensing unit and uses it as the input signal of the phase-sensitive detection circuit; the phase-shifting circuit is connected to the excitation signal and, after phase shifting, serves as the reference signal of the phase-sensitive detection circuit; the phase-sensitive detection circuit and the low-pass filter circuit demodulate the amplified differential sensing signal and extract the preliminary abrasive grain feature signal; the post-amplifier circuit further amplifies the preliminary abrasive grain feature signal to obtain the abrasive grain feature signal; and the signal acquisition circuit performs analog-to-digital conversion on the abrasive grain feature signal and transmits it to the host computer.

[0012] Furthermore, the skeleton, the first baffle, and the second baffle are made of polytetrafluoroethylene, ceramic, epoxy resin, or other non-metallic materials.

[0013] Furthermore, the flow channel is a non-metallic hollow pipe with a rectangular cross-section, used to provide an oil passage. When metal abrasive particles pass through the flow channel, the metal abrasive particles cause changes in the magnetic flux and induced voltage of the first induction coil and the second induction coil. The differential induction signal of the first induction coil and the second induction coil is a high-frequency carrier signal modulated by the abrasive particle characteristics.

[0014] As can be seen from the above technical solutions, this utility model generates a high-intensity radial magnetic field in the sensing area by placing two induction coils vertically and symmetrically in the radial plane at the center of the two excitation coils, which enhances the magnetization effect and eddy current effect of metal abrasive particles and significantly improves the sensitivity of abrasive particle detection; at the same time, the use of rectangular induction coils to form a large-diameter flow channel is suitable for high-flow abrasive particle detection applications. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the sensing unit structure of this utility model;

[0017] Figure 3 This is a cross-sectional view of the sensing unit of this utility model;

[0018] Figure 4 This is a schematic diagram of the coil structure in the sensing unit of this utility model;

[0019] Figure 5 This refers to the abrasive grain characteristic signal when iron abrasive grains pass through in the embodiments of this application;

[0020] Figure 6 This refers to the abrasive grain characteristic signal as copper abrasive grains pass through in the embodiments of this application;

[0021] In the diagram: 1. Skeleton; 2. First excitation coil; 3. Second excitation coil; 4. First induction coil; 5. Second induction coil; 6. First baffle; 7. Second baffle; 8. Flow channel; 9. Excitation resonant capacitor; 10. Induction resonant capacitor; 11. Excitation signal. Detailed Implementation

[0022] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0023] like Figure 1 The metal abrasive particle detection device based on radial magnetic field shown includes a sensing unit, a signal generation module, a signal processing module, and a power supply module.

[0024] Specifically, such as Figure 2-4 As shown, the sensing unit includes a cylindrical frame 1, a first excitation coil 2 and a second excitation coil 3 coaxially sleeved at both ends of the frame 1, a first induction coil 4 and a second induction coil 5 symmetrically arranged on both sides of the middle of the frame 1, a first baffle 6 coaxially sleeved on the frame 1 for clamping and fixing the first excitation coil 2 and the second excitation coil 3, a second baffle 7 sleeved on the frame 1 for fixing the first induction coil 4 and the second induction coil 5, and a flow channel 8 located in the sensing area of ​​the first induction coil 4 and the second induction coil 5 and penetrating the frame 1.

[0025] In specific operation, the first excitation coil 2 and the second excitation coil 3 are wound close to the frame 1 and the first baffle 6, and the second baffle 7 is provided with protrusions for winding the first induction coil 4 and the second induction coil 5; in this preferred embodiment, the diameter of the frame 1 is 15mm, and the frame 1, the first baffle 6 and the second baffle 7 are all made of epoxy resin material.

[0026] The signal generation module described in this preferred embodiment includes a high-frequency signal generator and a power amplifier, used to generate a 20Vpp, 160kHz high-frequency sinusoidal excitation signal, and to form a resonant circuit with a resonant frequency of 160kHz with the first excitation coil 2 and the second excitation coil 3 through a parallel excitation resonant capacitor 9. Both the first excitation coil 2 and the second excitation coil 3 are toroidal coils with the same winding direction, generating a uniform radial magnetic field in the central radial plane between them when energized. By driving the first excitation coil 2 and the second excitation coil 3 to generate the same radial magnetic field in the central radial plane, the superimposed radial magnetic field significantly enhances the magnetic field strength in the sensing area of ​​the flow channel 8, fundamentally solving the problem of insufficient magnetic field strength and thus insufficient sensitivity for detecting metal abrasive particles in existing inductive detection technologies. In this preferred embodiment, the first end of the first excitation coil 2 is connected to the end of the second excitation coil 3, and the end of the first excitation coil 2 is connected to the first end of the second excitation coil 3, respectively. The inner diameter of each coil is 15mm, the coil thickness is 2mm, the coil width is 1mm, the number of turns is 200, and the wire diameter is 0.1mm.

[0027] In this preferred embodiment, both the first induction coil 4 and the second induction coil 5 are rectangular coils with opposite winding directions. The first and second induction coils are arranged vertically and symmetrically on both sides of the center plane of the radial magnetic field generated by the excitation coil. The first and second induction coils 4 and 5 are connected in series with the induction resonant capacitor 10 to form a resonant circuit, the resonant frequency of which matches the excitation signal frequency. The output of the sensing unit is the differential induction signal of the first and second induction coils 4 and 5, i.e., a high-frequency carrier signal modulated by abrasive grain characteristics. In this preferred embodiment, the internal rectangles of the first and second induction coils 5 are both 4.1mm × 6.6mm, the coil thickness is 0.6mm, the coil width is 0.6mm, the number of turns is 144, and the wire diameter is 0.05mm.

[0028] According to the principle of electromagnetic induction, since the first induction coil 4 and the second induction coil 5 are located in the radial magnetic field generated by the excitation coil, they will generate the same induced voltage. When no metal abrasive particles pass through the flow channel 8, the differential induction signal of the first induction coil 4 and the second induction coil 5 is zero. When metal abrasive particles pass through the flow channel 8, the metal abrasive particles cause changes in the magnetic flux and induced voltage of the first induction coil 4 and the second induction coil 5. At this time, the differential induction signal of the first induction coil 4 and the second induction coil 5 is a high-frequency carrier signal modulated by the abrasive particle characteristics. The differential induction signal of the first induction coil 4 and the second induction coil 5 is used as the output of the sensing unit. Demodulating it can extract the abrasive particle characteristic signal, thereby determining the size, material, and other information of the metal abrasive particles. In this preferred embodiment, the flow channel 8 is a non-metallic hollow pipe with a rectangular cross-section and a large diameter, suitable for high-flow abrasive particle detection applications.

[0029] The abrasive particles can be categorized into ferromagnetic and non-ferromagnetic abrasive particles based on their material. When ferromagnetic abrasive particles pass through the flow channel 8, their relative permeability >> 1, resulting in a dominant magnetization effect and an increase in local magnetic flux. Conversely, when non-ferromagnetic abrasive particles pass through the rectangular channel, their relative permeability ≈ 1, leading to a dominant eddy current effect and a decrease in local magnetic flux. The local magnetic flux changes caused by ferromagnetic and non-ferromagnetic abrasive particles exhibit opposite trends, resulting in opposite phases in the abrasive particle characteristic signals. Therefore, the ferromagnetic nature of the abrasive particles can be quickly determined by observing the phase.

[0030] The signal processing module described in this preferred embodiment is used to receive the differential sensing signal output by the sensing unit and extract the wear particle characteristic signal. It includes a pre-amplifier circuit, a phase-shifting circuit, a phase-sensitive detection circuit, a low-pass filter circuit, a post-amplifier circuit, and a signal acquisition circuit. In specific implementations, such as... Figure 1As shown, in the signal processing module: the differential sensing signal output by the sensing unit is connected to a pre-differential amplifier for amplification, and the amplified differential sensing signal is connected to the input of a lock-in amplifier for demodulation; the excitation signal 11 generated by the signal generation module is not only used to drive the first excitation coil 2 and the second excitation coil 3, but is also connected to the phase shift circuit as a reference signal for the lock-in amplifier; by adjusting the phase of the phase shift circuit and the bandwidth of the low-pass filter, the phase-sensitive detection circuit can achieve the best demodulation effect and extract the preliminary abrasive feature signal from the amplified differential sensing signal; the post-amplifier circuit further amplifies the preliminary abrasive feature signal to obtain the abrasive feature signal; the signal acquisition circuit performs analog-to-digital conversion on the abrasive feature signal and transmits the data to the host computer.

[0031] Furthermore, such as Figure 5 and Figure 6 The images show the abrasive characteristic signals of spherical iron abrasive grains with a diameter of 500 μm and spherical copper abrasive grains with a diameter of 500 μm as they pass through the flow channel. The size of the abrasive grains can be determined based on their amplitude, and the ferromagnetic property of the abrasive grains can be determined based on their phase.

[0032] The above-described embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Any modifications and improvements made by those skilled in the art to the technical solutions of the present utility model without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A radial magnetic field-based metal abrasive grain detection device characterized by comprising: It includes a sensing unit, a signal generation module, a signal processing module, and a power supply module; The sensing unit includes a cylindrical frame, a first excitation coil and a second excitation coil coaxially sleeved at both ends of the frame, a first induction coil and a second induction coil symmetrically arranged on both sides of the middle of the frame, a first baffle coaxially sleeved on the frame for clamping and fixing the first excitation coil and the second excitation coil, a second baffle sleeved on the frame for fixing the first induction coil and the second induction coil, and a flow channel located in the sensing area of ​​the first induction coil and the second induction coil and penetrating the frame. The first excitation coil and the second excitation coil are wound close to the frame and the first baffle. The second baffle is provided with protrusions for winding the first induction coil and the second induction coil.

2. The radial magnetic field-based metal abrasive grain detection device according to claim 1, wherein The signal generation module includes a high-frequency signal generator and a power amplifier, used to generate a high-frequency sinusoidal excitation signal of 10kHz-1MHz, and to form a resonant circuit with the first excitation coil and the second excitation coil through a parallel excitation resonant capacitor; the first excitation coil and the second excitation coil are both ring coils and they are wound in the same direction, and when energized, they can generate a uniform radial magnetic field in the central radial plane between them.

3. The radial magnetic field-based metal abrasive grain detection device according to claim 2, characterized by The first and second induction coils are both rectangular coils and are wound in opposite directions; the first and second induction coils are arranged vertically and symmetrically on both sides of the center plane of the radial magnetic field generated by the excitation coil; the first and second induction coils are connected in series with the induction resonant capacitor to form a resonant circuit, and the resonant frequency of the resonant circuit matches the frequency of the excitation signal; the output of the sensing unit is the differential induction signal of the first and second induction coils.

4. The radial magnetic field-based metal abrasive grain detection device according to claim 3, characterized by The signal processing module is used to receive the differential sensing signal output by the sensing unit and extract the wear particle characteristic signal, including a pre-differential amplifier circuit, a phase shifting circuit, a phase-sensitive detection circuit, a low-pass filter circuit, a post-amplifier circuit, and a signal acquisition circuit.

5. The radial magnetic field-based metal abrasive particle detection device according to claim 4, wherein In the signal processing module, the pre-amplifier circuit amplifies the differential sensing signal output by the sensing unit and uses it as the input signal of the phase-sensitive detection circuit; the phase-shifting circuit is connected to the excitation signal and, after phase shifting, serves as the reference signal of the phase-sensitive detection circuit; the phase-sensitive detection circuit and the low-pass filter circuit demodulate the amplified differential sensing signal and extract the preliminary abrasive grain feature signal; the post-amplifier circuit further amplifies the preliminary abrasive grain feature signal to obtain the abrasive grain feature signal; and the signal acquisition circuit converts the abrasive grain feature signal from analog to digital and transmits it to the host computer.

6. The radial magnetic field-based metal abrasive particle detection device according to claim 1, wherein The frame, the first baffle, and the second baffle are made of polytetrafluoroethylene, ceramic, epoxy resin, or other non-metallic materials.

7. The radial magnetic field-based metal abrasive grain detection device according to claim 1, wherein The flow channel is a non-metallic hollow pipe with a rectangular cross-section, used to provide an oil passage. When metal abrasive particles pass through the flow channel, the metal abrasive particles cause changes in the magnetic flux and induced voltage of the first induction coil and the second induction coil. The differential induction signal of the first induction coil and the second induction coil is a high-frequency carrier signal modulated by the abrasive particle characteristics.

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