Online iron powder content detection device and method

Abstract

The invention discloses an online iron powder content detection device and method. The online iron powder content detection device comprises an online measurement module, a filtering and amplifying module, a control module, a communication module and a calculation module, the on-line measurement module is used for adsorbing iron powder and outputting a detection signal according to the condition of adsorbing the iron powder; the control module is used for controlling the on-line measurement module to operate, acquiring a detection signal and controlling the communication module and the filtering and amplifying module to work; the filtering and amplifying module is used for carrying out noise removal and signal amplification on the detection signal; and the communication module is used for sending the processed detection signal to the calculation module for iron powder concentration calculation. According to the invention, online measurement of the concentration of the iron powder can be realized, and the problems that only offline manual detection can be carried out and large-range rapid detection is difficult to realize in the prior art can be solved.

Description

Technical Field

[0001] The present invention relates to the field of industrial robots, and in particular to an online iron powder content detection device and method. Background Art

[0002] In the field of industrial robots, the reducer is one of its core components, and its performance directly affects the stability and reliability of the robot. During the operation of the reducer, the meshing between the gears and the rolling of the rolling elements in the bearings will cause wear and tear, forming iron filings (powder), which are carried away by the lubricating oil or grease. At present, a common method to determine whether the industrial robot reducer needs to replace the lubricating oil and the degree of aging of the reducer is to detect the iron powder concentration in the lubricating oil or grease. However, the existing iron powder concentration detection method has the following shortcomings: First, existing detection methods usually require sampling when the robot is shut down for maintenance, which not only increases production costs, but also causes production interruptions and affects production efficiency. Secondly, the detection cycle usually needs to be arranged according to the production plan, which may lead to a long detection cycle and fail to reflect the actual wear status of the reducer in a timely manner, thereby delaying maintenance and increasing the risk of equipment failure. In addition, existing detection methods usually require the use of external specialized iron powder concentration detection instruments, that is, they mainly rely on offline manual detection methods, which not only increases the equipment investment cost, but also increases the complexity of operation. When conducting large-scale iron powder concentration detection within a limited time, it takes a lot of time, manpower and material resources, which brings a heavy burden. Therefore, how to realize online measurement of iron powder concentration when the robot is running, avoid downtime sampling, and reduce detection time and cost has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The purpose of the present invention is to provide an online iron powder content detection device and method, which can realize online measurement of iron powder concentration and solve the problem that only offline manual detection can be performed in the prior art, and it is difficult to realize large-scale rapid detection.

[0004] In order to solve the above technical problems, the present invention provides an online iron powder content detection device, including an online measurement module, a filter amplification module, a control module, a communication module and a calculation module; The online measurement module is used to adsorb iron powder and output a detection signal according to the situation of adsorbing iron powder; The control module is used to control the operation of the online measurement module and obtain the detection signal, and control the operation of the communication module and the filtering and amplifying module; The filtering and amplifying module is used to remove noise and amplify the detection signal of the online measurement module; The communication module is used to send the processed detection signal to the calculation module to calculate the iron powder concentration.

[0005] Further, the online measurement module includes a connecting rod and a first conductive component and a second conductive component constituting a flat plate capacitor; A magnetic conductive layer is provided on one side of the first conductive component close to the second conductive component, for absorbing iron powder; The connecting rod is fixedly connected to the first conductive component; and a predetermined distance is maintained between the first conductive component and the second conductive component.

[0006] Furthermore, a non-magnetic, corrosion-resistant metal layer is provided on a side of the first conductive component away from the second conductive component.

[0007] Further, the online measurement module includes a magnet rod, an upper clamping rod and a lower clamping rod; Two ends of the magnet bar are connected to the upper clamping rod and the lower clamping rod respectively.

[0008] Furthermore, it also includes a shell and a power supply module; the outer wall of the shell is provided with threads; the filter amplification module, the control module, the power supply module and the communication module are all located in the shell; the online measurement module is arranged at the end of the shell and can extend into the grease area inside the reducer gear box; the power supply module is connected to the online measurement module, the communication module, the filter amplification module and the control module; the control module is also used to monitor the power of the power supply module.

[0009] In addition, the present invention also proposes an online iron powder content detection method, using the online iron powder content detection device as described above, which specifically includes the following: Record the initial detection signal value of the online measurement module; When the reducer is running, use the online measurement module to absorb iron powder and obtain the current detection signal value; The iron powder concentration is calculated based on the difference between the initial detection signal value and the current detection signal value.

[0010] Furthermore, it also includes: For the online measurement module using a flat plate capacitor structure, the capacitance value is calculated according to the flat plate capacitor formula C=εS / d, where ε is the dielectric constant of the medium between the plates, in units of F / m, and S is the area of ​​the two plates facing each other, in units of m 2 , d is the distance between the two plates, in m; The change of capacitance value is obtained by detecting the change of d value, wherein the decrease of d value is the thickness of adsorbed iron powder; In the experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by actual reducer wear; Record the initial capacitance value C0 before adding iron powder, the capacitance value C1 after adding iron powder, calculate the capacitance value difference ΔC=C1-C0, establish a corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration, and the corresponding relationship curve satisfies the functional relationship of c'=aX+b, wherein c' is the iron powder concentration, X is the capacitance value difference ΔC, a is the proportionality coefficient, and b is the calibration deviation value; calculate the iron powder concentration c'.

[0011] Furthermore, it also includes: For the online measurement module using a magnet bar structure, the initial conductive properties of the magnet bar are recorded in an initial state; The power supply module applies a voltage for several seconds at both ends of the magnet bar; the current value flowing through the magnet bar is measured to obtain an initial current value; At preset time intervals, the same voltage is applied to both ends of the magnet bar. After the iron powder is adsorbed on the surface of the magnet bar, the conductive property of the magnet bar changes, causing the current value to change, and then the current current value is measured; In the experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by the actual reducer wear; the initial current value I0 before adding the iron powder and the current value I after adding the iron powder are recorded, and the current value difference ΔI=I-I0 is calculated; by measuring the current value under different iron powder content conditions, the corresponding data of the current value difference and the iron powder content are obtained, and the corresponding relationship function between the current value difference and the iron powder concentration is obtained by fitting; The current iron powder concentration is calculated according to the difference between the current current value and the initial current value in combination with a pre-calibrated corresponding relationship function between the current difference and the iron powder concentration.

[0012] Furthermore, it also includes: filtering and denoising the detection signal; amplifying the processed signal; sending the amplified signal to the calculation module through the communication module; and issuing an alarm according to a preset iron powder concentration threshold.

[0013] Furthermore, the amplified signal is sent to the calculation module through the communication module, which specifically includes: recording the time and iron powder concentration value of each detection; drawing a trend graph of the iron powder concentration changing with time; judging the degree of reducer wear and whether to replace the lubricating oil based on the trend graph and set standards; when the iron powder concentration exceeds a preset threshold, issuing a maintenance reminder.

[0014] Through the above technical solution, the present invention has the following beneficial effects: Through the settings of an online measurement module, a filter amplifier module, a control module, a communication module and a calculation module; and the online measurement module is used to adsorb iron powder and output a detection signal according to the situation of adsorbing iron powder; the control module is used to control the operation of the online measurement module and obtain the detection signal, and control the communication module and the filter amplifier module to work; the filter amplifier module is used to remove noise and amplify the signal of the detection signal; the communication module is used to send the processed detection signal to the calculation module to calculate the iron powder concentration. The present invention can realize the online measurement of iron powder concentration, avoid downtime sampling, and reduce detection time and cost.

[0015] In addition, by establishing a corresponding relationship curve between the capacitance value difference and the iron powder concentration, or a corresponding relationship curve between the current difference and the iron powder concentration, the present invention can automatically monitor the change of iron powder concentration online frequently, and issue a maintenance reminder when it exceeds a preset threshold, thereby improving equipment maintenance efficiency and extending equipment service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of an online iron powder content detection device in one embodiment of the present invention; Figure 2 It is a schematic diagram of the overall structure of an online iron powder content detection device in another embodiment of the present invention; Figure 3 The figure is a flow chart of an online iron powder content detection method according to an embodiment of the present invention.

[0017] In the figure, 11, a first conductive component; 12, a second conductive component; 13, a connecting rod; 101, a magnetic rod; 102, an upper clamping rod; 103, a lower clamping rod; 2. Filter amplifier module; 3. Power supply module; 4. Communication module; 5. Housing; 6. Grease area inside the gearbox; 7. Control module. DETAILED DESCRIPTION

[0018] The following will be described in more detail with reference to the accompanying drawings, wherein preferred embodiments of the present invention are shown, and it should be understood that those skilled in the art may modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as being widely known to those skilled in the art and not as a limitation of the present invention.

[0019] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and are not in exact proportions, and are only used to facilitate and clearly assist in illustrating the purpose of the embodiments of the present invention.

[0020] like Figure 1-Figure 2As shown, an embodiment of the present invention proposes a convenient and practical online iron powder content detection device, including an online measurement module, a filter amplification module 2, a control module 7, a power supply module 3, a communication module 4 and a calculation module (not shown in the figure for the sake of simplicity of the diagram).

[0021] Specifically, the online measurement module is used to adsorb iron powder and output a detection signal according to the situation of adsorbing iron powder; the control module 7 is used to control the operation of the online measurement module and obtain the detection signal, control the operation of the communication module 4 and the filter amplification module 2, and monitor the power of the power supply module 3; the filter amplification module 2 is used to remove noise and amplify the detection signal of the online measurement module; the power supply module 3 is connected to the online measurement module, the communication module 4, the filter amplification module 2 and the control module 7; the communication module 4 is used to send the processed detection signal to the calculation module to calculate the iron powder concentration. Among them, the control module 7 controls the operation of the online measurement module, specifically refers to controlling the online measurement module to be powered on for a period of time (for example, for a few seconds) for detection.

[0022] In one embodiment, the structure of the online measurement module can be in various forms, such as a flat capacitor structure or a magnet bar 101 structure, to adapt to different detection requirements and environmental conditions. The filter amplifier module 2 is responsible for removing noise and amplifying the detection signal obtained by the online measurement module to improve the accuracy and reliability of the signal and enhance the stability of the detection result. The control module 7 not only controls the operation of the online measurement module to obtain accurate detection signals, but also controls the communication module 4 to perform the sending action, sends the processed detection signal to the calculation module in time for iron powder concentration calculation, and monitors the power of the power supply module 3 to ensure the continuous and stable operation of the device. The power supply module 3 can provide stable power support for the entire device, expand the scope of application and working time of the device. The communication module 4 can use wireless communication technology, such as low-power consumption protocols such as zigbee and Lora, to send the processed detection signal to the calculation module, which is convenient for remote monitoring and data transmission, and improves the convenience and real-time performance of the detection. The calculation module receives the detection signal sent by the communication module 4, and can calculate the iron powder concentration according to the preset algorithm and model, providing users with accurate detection results and subsequent processing basis.

[0023] In this embodiment, the control module 7 not only controls the operation of the online measurement module, but is also responsible for controlling the working sequence of the filter amplifier module 2. Specifically, the control module 7 controls the filter amplifier module 2 to perform signal processing within the detection cycle, and does not provide power outside the detection cycle, thereby optimizing the energy use of the power supply module 3, extending the battery life, and reducing the frequency of battery replacement.

[0024] This embodiment can achieve rapid and accurate detection of iron powder content through the coordinated work of various modules, and can also improve detection efficiency and reliability of results.

[0025] In a specific embodiment, continue to refer to Figure 1 As shown, the online measurement module adopts a flat plate capacitor structure. Specifically, the online measurement module includes a connecting rod 13 and a first conductive component 11 and a second conductive component 12 constituting a flat plate capacitor, that is, the first conductive component 11 and the second conductive component 12 are arranged opposite to each other; More specifically, a magnetic conductive layer is provided on one side of the first conductive component 11 close to the second conductive component 12 for adsorbing iron powder; and the magnetic conductive layer is made of corrosion-resistant conductive metal, has strong magnetism, and can effectively adsorb iron powder, thereby improving the sensitivity and accuracy of detection. The first conductive component 11 and the second conductive component 12 are respectively connected to the positive and negative poles of the power supply module 3 through a first connecting line (such as a wire); the connecting rod 13 is fixedly connected to the first conductive component 11, and the first conductive component 11 and the second conductive component 12 are arranged relative to each other and retain a predetermined spacing. As the iron powder is continuously adsorbed by the magnetic conductive layer of the first conductive component 11, the actual spacing d value will gradually decrease, thereby causing a change in the capacitance value. This fixed structure design is simple and reliable, has no moving parts, reduces failure points, and improves the stability and reliability of the device.

[0026] In addition, the present embodiment further includes a housing 5. Specifically, the outer wall of the housing 5 is provided with threads, which facilitates the installation of the device at the oil outlet position of the reducer gearbox, replaces the original sealing screws, and achieves close contact with the grease area 6 inside the gearbox. Furthermore, the filter amplification module 2, the control module 7, the power supply module 3 and the communication module 4 are all located in the housing 5; the online measurement module is arranged at the end of the housing 5, and can extend into the grease area 6 inside the reducer gearbox, directly contact the lubricating oil / grease, absorb iron powder, and obtain accurate detection signals. The device structure of this embodiment is reasonably designed and easy to install. It can effectively improve the accuracy and convenience of detection and enhance the practicality and reliability of the device.

[0027] Preferably, both the first conductive component 11 and the second conductive component 12 are conductive metal discs. A non-magnetic corrosion-resistant layer is provided on the side of the first conductive component 11 away from the second conductive component 12. The first conductive component 11 is disc-shaped, and a magnetic corrosion-resistant metal layer is provided on the side of the first conductive component 11 close to the second conductive component 12; the second conductive component 12 is a non-magnetic conductive metal disc; the first conductive component 11 and the second conductive component 12 are aligned in center.

[0028] In this embodiment, a non-magnetic corrosion-resistant metal layer is provided on the side of the first conductive component 11 away from the second conductive component 12. The metal layer has the function of reducing or shielding magnetism, so that the side of the first conductive component 11 close to the second conductive component 12 can absorb more iron powder, thereby improving the measurement accuracy. At the same time, the corrosion-resistant metal layer can prevent the chemical substances in the lubricating grease from corroding the detection device, and prevent impurities from mixing into the lubricating oil and causing the lubricating oil to deteriorate. In addition, the structural design of the metal layer on both sides of the first conductive component 11 improves the overall strength and is not easy to be damaged.

[0029] In another specific embodiment, continue to refer to Figure 2 As shown, the online measurement module may also adopt a magnet rod 101 structure. Specifically, the online measurement module includes a magnet rod 101, an upper clamping rod 102 and a lower clamping rod 103.

[0030] More specifically, the two ends of the magnet rod 101 are connected to the upper clamp rod 102 and the lower clamp rod 103 respectively; the upper clamp rod 102 and the lower clamp rod 103 are connected to the positive pole and the negative pole of the power supply module 3 respectively through a second connecting line (such as a wire).

[0031] In this embodiment, the magnet bar 101 is made of a material with strong magnetism, such as a ferrite magnet, which has poor electrical conductivity but can effectively absorb iron powder. The upper clamping rod 102 and the lower clamping rod 103 are respectively connected to the two ends of the magnet bar 101 to form a stable structure. The upper clamping rod 102 and the lower clamping rod 103 are respectively connected to the positive and negative poles of the power supply module 3 through a second connecting line to provide electrical energy for the magnet bar 101. The online measurement module of this magnet bar 101 structure utilizes the strong magnetism of the magnet bar 101 to absorb iron powder. As the absorbed iron powder covers more and more of the surface of the magnet bar, the electrical conductivity continues to improve. The detection signal is obtained by detecting the change in the electrical conductivity of the magnet bar 101, which has the advantages of simple structure and low cost, is suitable for a variety of detection environments and conditions, and enhances the applicability and flexibility of the device.

[0032] In addition, the present embodiment further includes a housing 5. Specifically, the outer wall of the housing 5 is provided with threads, which facilitates the installation of the device at the oil outlet position of the reducer gearbox, replaces the original sealing screws, and achieves close contact with the grease area 6 inside the gearbox. Furthermore, the filter amplification module 2, the control module 7, the power supply module 3 and the communication module 4 are all located in the housing 5; the online measurement module is arranged at the end of the housing 5, and can extend into the grease area 6 inside the reducer gearbox, directly contact the lubricating oil / grease, absorb iron powder, and obtain accurate detection signals. The device structure of this embodiment is reasonably designed and easy to install. It can effectively improve the accuracy and convenience of detection and enhance the practicality and reliability of the device.

[0033] In addition, if Figure 3 As shown, this embodiment also proposes an online iron powder content detection method, using the online iron powder content detection device as described above, specifically comprising the following steps: S1, record the initial detection signal value of the online measurement module; S2. When the reducer is running, use the online measurement module to absorb iron powder and obtain the current detection signal value; S3. Calculate the iron powder concentration according to the difference between the initial detection signal value and the current detection signal value.

[0034] In a specific example, this embodiment further includes: for the online measurement module using a flat plate capacitor structure, the capacitance value is calculated according to the flat plate capacitor formula C=εS / d, and the unit is F (farad). Among them, ε is the dielectric constant of the medium between the flat plates (i.e., the first conductive component 11 and the second conductive component 12), and the unit is F / m, and S is the facing area of ​​the two flat plates (i.e., the first conductive component 11 and the second conductive component 12), and the unit is m 2 , since the two plates are fixedly aligned, this value remains unchanged; d is the distance between the two plates (i.e., the first conductive component 11 and the second conductive component 12), and the unit is m. As the iron powder is adsorbed by the magnetic conductive layer of the first conductive component 11, there are two main influencing factors: one is that the d value decreases, that is, the effective distance between the two plates decreases; the other is that the accumulation of iron powder between the plates may have a slight effect on the dielectric constant ε of the medium. This device mainly uses the capacitance change caused by the change in d value as the measurement basis, because the magnetic conductive layer will preferentially adsorb the iron powder and concentrate it on the surface of the first conductive component 11, so that the change in d value becomes the dominant factor. During the calibration process, the corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration established by experiment has comprehensively considered the combined influence of these two factors.

[0035] In this embodiment, under an experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by the actual reducer wear; the capacitance value difference ΔC after each addition is recorded, and the corresponding data of the capacitance value difference ΔC and the iron powder content are obtained, and the corresponding relationship function of the capacitance value difference ΔC and the iron powder concentration is obtained by fitting. More specifically, the initial capacitance value C0 before adding iron powder and the capacitance value C1 after adding iron powder are recorded, and the capacitance value difference ΔC=C1-C0 is calculated, and a corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration is established, and the corresponding relationship curve satisfies the functional relationship of c'=aX+b, where c' is the iron powder concentration, X is the capacitance value difference ΔC, a is the proportionality coefficient, and b is the calibration deviation value; the iron powder concentration c' is calculated.

[0036] Among them, when calibrating, it is necessary to use the lubricating oil of a new robot reducer, adjust the temperature and pressure of the experimental environment to conditions similar to the actual reducer working environment, and simulate the working state of the gearbox by stirring the lubricating oil. By analyzing the wear particles of the actual reducer, it is determined that the particle size range of the experimental iron powder is 10μm~100μm. Different masses of specific particle size iron powder are gradually added to the lubricating oil, and the capacitance value at each iron powder content is measured. Based on the capacitance value of pure lubricating oil, the capacitance value difference ΔC corresponding to different iron powder contents is calculated. These experimental data are fitted to establish the relationship function between the capacitance value difference ΔC and the iron powder content.

[0037] For example, in an experimental environment, using the same type of new oil / grease and operating environment (temperature and pressure), perform the following calibration: record the initial capacitance value C0 when there is no iron powder, and gradually add iron powder, where the particle size of the iron powder is determined based on the particle diameter produced by actual reducer wear (i.e., iron powder with a particle size similar to that produced by actual gearbox wear, such as 10μm~100μm iron powder); record the capacitance value C1 and the corresponding iron powder concentration c' (which can be measured using a third-party instrument) after each addition; calculate the capacitance difference ΔC=C1-C0; establish a corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration, where the corresponding relationship curve satisfies the functional relationship of c'=aX+b, where c' is the iron powder concentration, X is the capacitance value difference ΔC, a is the proportionality coefficient (i.e., the main proportionality coefficient), and b is the calibration deviation value (i.e., the deviation value used for calibration).

[0038] This embodiment establishes a corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration through experiments, which provides an accurate calculation basis for actual detection, improves the accuracy and reliability of detection, and enhances the detection capability of the device. In addition, the same type of lubricating oil and reducer only need to perform this type of calibration operation once. In subsequent use, the current iron powder concentration can be obtained by substituting the detected ΔC value into the calibration formula. This embodiment establishes a calibration curve through experiments, which provides an accurate calculation basis for actual detection, and improves the accuracy and reliability of detection.

[0039] In another specific example, this embodiment also includes: for the online measurement module using the magnet rod 101 structure, the initial conductivity of the magnet rod 101 is recorded in the initial state; the power supply module 3 applies a voltage for several seconds at both ends of the magnet rod 101; the current value flowing through the magnet rod 101 is measured to obtain the initial current value; at a preset time interval, the same voltage is applied to both ends of the magnet rod 101, and after the iron powder is adsorbed on the surface of the magnet rod, the conductivity of the magnet rod changes, causing the current value to change, and then the current current value is measured. In an experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by actual reducer wear; the initial current value I0 before adding iron powder and the current value I after adding iron powder are recorded, and the current value difference ΔI=I-I0 is calculated; by measuring the current value under different iron powder content conditions, the corresponding data of the current value difference and the iron powder content are obtained, and the corresponding relationship function between the current value difference and the iron powder concentration is fitted; according to the difference between the current current value and the initial current value, combined with the pre-calibrated corresponding relationship function between the current difference and the iron powder concentration, the current iron powder concentration is calculated.

[0040] The magnet bar itself has a certain conductivity. When the iron powder is adsorbed on its surface, the conductivity of the iron powder enhances the overall conductivity of the magnet bar, thereby increasing the measured current value. The current iron powder concentration is calculated based on the difference between the current current value and the initial current value, combined with a pre-calibrated function of the corresponding relationship between the current difference and the iron powder concentration.

[0041] In this embodiment, as the iron powder gathers on the surface of the magnet bar 101, the conductivity of the magnet bar 101 gradually increases, and the current value flowing through the magnet bar 101 also increases accordingly. According to the difference between the current current value and the initial current value, combined with the pre-calibrated corresponding relationship curve between the current difference and the iron powder concentration, the current iron powder concentration is calculated. This embodiment uses the change in the conductivity of the magnet bar 101 to detect the iron powder concentration, has the advantages of simple structure and low cost, is applicable to a variety of detection environments and conditions, and enhances the applicability and flexibility of the device.

[0042] In one embodiment, for example, in the initial state, the resistance R0 of the magnet bar 101 is recorded by applying a known voltage V0 across the magnet bar 101 and measuring the current I0 flowing therethrough, using Ohm's law R0=V0 / I0. A voltage V is applied across the magnet bar 101 for a few seconds and the initial current I0 is measured. After a preset time interval, the same voltage V is applied across the magnet bar 101 again and the current I flowing therethrough is measured. The change in current ∆I=I-I0 is calculated.

[0043] The current iron powder concentration is calculated based on the corresponding relationship curve between the pre-calibrated current difference ∆I and the iron powder concentration C. This relationship can be obtained through experiments, for example, by gradually adding iron powder in a controlled environment and measuring the corresponding current changes. In the experiment, iron powder is gradually added around the magnet bar 101. The particle size of the iron powder is determined according to the particle diameter generated by the actual reducer wear (i.e., iron powder with a particle size similar to that generated by the actual gearbox wear, such as 10μm~100μm iron powder). After each addition of iron powder, the current I is measured and ∆I is calculated. Using these data points, a functional relationship between ∆I and the iron powder concentration c' is established, such as a linear relationship c'=a∆I+b, where a and b are parameters obtained by data fitting.

[0044] Preferably, this embodiment also includes: filtering and denoising the detection signal to remove noise interference in the signal and improve the accuracy and reliability of the signal; amplifying the processed signal to enhance the amplitude of the signal to facilitate subsequent detection and calculation; sending the amplified signal to the calculation module through the communication module 4; issuing an alarm according to a preset iron powder concentration threshold, and issuing a maintenance reminder when the iron powder concentration exceeds the preset threshold to remind the user to perform maintenance and processing in time.

[0045] Furthermore, the amplified signal is sent to the calculation module through the communication module 4, which specifically includes: recording the time and iron powder concentration value of each detection to form a complete detection data record; drawing a trend graph of the iron powder concentration changing with time, through which the change of the iron powder concentration can be visually observed, providing a basis for subsequent analysis and prediction; judging the degree of reducer wear and whether to replace the lubricating oil according to the trend graph and the set standards; when the iron powder concentration exceeds the preset threshold, issuing a maintenance reminder.

[0046] In this embodiment, an online measurement module using a flat plate capacitor structure is taken as an example, for example, ε=4×8.854187817×10 −12 F / m (i.e. ε=ε r ε0, relative dielectric constant ε r It is usually between 2 and 5, for example, take 4, and then multiply it by the vacuum dielectric constant ε0 = 8.854187817 × 10 −12 F / m≈8.854×10 −12 F / m); For example, taking the common oil outlet sealing screw G3 / 4 as an example (inner diameter is about 24mm), the area of ​​the circular plate is 452×10 -6 m 2 ; d For example, take 5×10 -3 m (i.e. the initial predetermined spacing is set to 5×10 -3m, as the iron powder accumulates, the actual spacing will gradually decrease), and we can get C≈3.2pF. The specific calculation process is as follows: According to the plate capacitance formula C=εS / d, the capacitance value is calculated, then C=(4×8.854×10 −12 ×452×10 -6 ) / (5×10 -3 )≈3.2×10 −12 F=3.2pF. That is, C0=3.2pF at the beginning, and after iron powder accumulates, C1=3.5pF is measured, then: ΔC=C1-C0=3.5pF-3.2pF=0.3pF. This initial capacitance value (C=3.2pF) is used as the reference value C0 of the device. The iron powder concentration c'=5ppm / pF×0.3pF=1.5ppm can be calculated. In this way, real-time monitoring of the iron powder concentration in the lubricating oil can be achieved.

[0047] Therefore, when iron powder gradually accumulates on the surface of the first conductive component 11, the d value will gradually decrease, resulting in an increase in the actual capacitance value C1. The degree of iron powder accumulation can be reflected by calculating the change in capacitance value ΔC (i.e., C1-C0), thereby enabling the monitoring of the iron powder content in the lubricating oil. Monitoring can also be performed at set time intervals, and since the iron powder concentration changes slowly, the set time interval can be set according to actual conditions, such as 1 hour or more.

[0048] In addition, taking the online measurement module using the magnet bar 101 structure as an example, due to the poor conductivity of ferrite materials (ceramic materials), the initial current I0 is very small. For example, for a ferrite magnet bar with a length of 10 mm and a diameter of 2 mm, its resistance value is about 3.18 megohms at room temperature and about 3.26 megohms at the reducer operating temperature (about 50°C). When a 2V voltage is applied to both ends, the initial current I0 is about 0.61μA (when there is no iron powder). When iron powder is adsorbed on the surface of the magnet bar 101, for example, the current I=0.8μA is measured. Calculate the current difference: ΔI=I-I0=0.8μA-0.61μA=0.19μA. If the corresponding relationship obtained by experiment is c'=2.5ΔI+0: c'=2.5ppm / μA×0.19μA=0.475ppm. In this way, by measuring the change of tiny current, the iron powder concentration c' adsorbed by the magnet bar 101 can be accurately inferred.

[0049] In summary, the online iron powder content detection device and method proposed by the present invention have the following advantages: Through the settings of an online measurement module, a filter amplifier module, a control module, a communication module and a calculation module; and the online measurement module is used to adsorb iron powder and output a detection signal according to the situation of adsorbing iron powder; the control module is used to control the operation of the online measurement module and obtain the detection signal, and control the communication module and the filter amplifier module to work; the filter amplifier module is used to remove noise and amplify the signal of the detection signal; the communication module is used to send the processed detection signal to the calculation module to calculate the iron powder concentration. The present invention can realize the online measurement of iron powder concentration, avoid downtime sampling, and reduce detection time and cost.

[0050] In addition, by establishing a corresponding relationship curve between the capacitance value difference and the iron powder concentration, or a corresponding relationship curve between the current difference and the iron powder concentration, the present invention can automatically monitor the change of iron powder concentration online frequently, and issue a maintenance reminder when it exceeds a preset threshold, thereby improving equipment maintenance efficiency and extending equipment service life.

[0051] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An online iron powder content detection device, characterized in that: It includes an online measurement module, a filtering and amplifying module, a control module, a communication module and a calculation module; The online measurement module is used to adsorb iron powder and output a detection signal according to the situation of adsorbing iron powder; The control module is used to control the operation of the online measurement module and obtain the detection signal, and control the operation of the communication module and the filtering and amplifying module; The filtering and amplifying module is used to remove noise and amplify the detection signal; The communication module is used to send the processed detection signal to the calculation module to calculate the iron powder concentration.

2. The online iron powder content detection device according to claim 1, characterized in that: The online measurement module includes a connecting rod and a first conductive component and a second conductive component constituting a plate capacitor; A magnetic conductive layer is provided on one side of the first conductive component close to the second conductive component, for absorbing iron powder; The connecting rod is fixedly connected to the first conductive component; a predetermined distance is maintained between the first conductive component and the second conductive component, and the predetermined distance varies with the amount of adsorbed iron powder.

3. The online iron powder content detection device according to claim 2, characterized in that: A non-magnetic, corrosion-resistant metal layer is disposed on a side of the first conductive component away from the second conductive component.

4. The online iron powder content detection device according to claim 1, characterized in that: The online measurement module includes a magnet rod, an upper clamping rod and a lower clamping rod; Two ends of the magnet bar are connected to the upper clamping rod and the lower clamping rod respectively.

5. The online iron powder content detection device according to claim 1, characterized in that: It also includes a shell and a power supply module; the outer wall of the shell is provided with threads; the filter amplification module, the control module, the power supply module and the communication module are all located in the shell; the online measurement module is arranged at the end of the shell and can extend into the grease area inside the reducer gear box; the power supply module is connected to the online measurement module, the communication module, the filter amplification module and the control module; the control module is also used to monitor the power of the power supply module.

6. An online iron powder content detection method, using the online iron powder content detection device as described in any one of claims 1 to 5, characterized in that: The details include: Record the initial detection signal value of the online measurement module; When the reducer is running, use the online measurement module to absorb iron powder and obtain the current detection signal value; The iron powder concentration is calculated based on the difference between the initial detection signal value and the current detection signal value.

7. The online iron powder content detection method according to claim 6, characterized in that: Also includes: For the online measurement module using a flat plate capacitor structure, the capacitance value is calculated according to the flat plate capacitor formula C=εS / d, where ε is the dielectric constant of the medium between the plates, in units of F / m, and S is the area of ​​the two plates facing each other, in units of m 2 , d is the distance between the two plates, in m; The change of capacitance value is obtained by detecting the change of d value, wherein the decrease of d value is the thickness of adsorbed iron powder; In the experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by actual reducer wear; Record the initial capacitance value C0 before adding iron powder, the capacitance value C1 after adding iron powder, calculate the capacitance value difference ΔC=C1-C0, establish a corresponding relationship curve between the capacitance value difference ΔC and the iron powder concentration, and the corresponding relationship curve satisfies the functional relationship of c'=aX+b, wherein c' is the iron powder concentration, X is the capacitance value difference ΔC, a is the proportionality coefficient, and b is the calibration deviation value; calculate the iron powder concentration c'.

8. The online iron powder content detection method according to claim 6, characterized in that: Also includes: For the online measurement module using a magnet bar structure, the initial conductive properties of the magnet bar are recorded in an initial state; The power supply module applies a voltage for several seconds at both ends of the magnet bar; the current value flowing through the magnet bar is measured to obtain an initial current value; At preset time intervals, the same voltage is applied to both ends of the magnet bar. After the iron powder is adsorbed on the surface of the magnet bar, the conductive property of the magnet bar changes, causing the current value to change, and then the current current value is measured; In the experimental environment, iron powder is added for calibration, and the particle size of the iron powder is determined according to the particle diameter generated by the actual reducer wear; the initial current value I0 before adding the iron powder and the current value I after adding the iron powder are recorded, and the current value difference ΔI=I-I0 is calculated; by measuring the current value under different iron powder content conditions, the corresponding data of the current value difference and the iron powder content are obtained, and the corresponding relationship function between the current value difference and the iron powder concentration is obtained by fitting; The current iron powder concentration is calculated according to the difference between the current current value and the initial current value in combination with a pre-calibrated corresponding relationship function between the current difference and the iron powder concentration.

9. The online iron powder content detection method according to claim 6, characterized in that: The method also includes: filtering and denoising the detection signal; amplifying the processed signal; sending the amplified signal to the calculation module through the communication module; and giving an alarm according to a preset iron powder concentration threshold.

10. The online iron powder content detection method according to claim 9, characterized in that: The amplified signal is sent to the calculation module through the communication module, which specifically includes: recording the time and iron powder concentration value of each detection; drawing a trend graph of the iron powder concentration changing with time; judging the degree of reducer wear and whether to replace the lubricating oil based on the trend graph and set standards; when the iron powder concentration exceeds a preset threshold, issuing a maintenance reminder.

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