Oil detection sensor with temperature compensation function

Abstract

The utility model relates to an oil detection sensor with a temperature compensation function, which comprises a sensor detection unit, the sensor detection unit comprises a microfluid chip, an excitation unit and a sensing unit, the microfluid chip comprises a micro-channel, a substrate for fixing the micro-channel and a model material, the sensing unit comprises a solenoid coil and a capacitor which are arranged in parallel, the solenoid coil is arranged outside the micro-channel in a sleeving mode, and the excitation unit is electrically connected with the sensing unit through an insulated wire. The device has the advantages of being high in speed, high in precision, low in cost and the like, pollutants in lubricating grease can be rapidly and accurately detected in a low-cost and maintenance-free mode, the abrasion condition of mechanical equipment is judged by detecting and analyzing information of metal particles in oil liquid, and major faults of the mechanical equipment are prevented. Meanwhile, the device is portable, convenient to use and wide in application range, conforms to the oil detection environment in practical application, reduces the influence of temperature on the detection result, and has high application and popularization value.

Description

Technical Field

[0001] The utility model relates to the technical field of ship oil detection sensors, in particular to an oil detection sensor with a temperature compensation function. Background Art

[0002] When mechanical equipment is put into operation, friction and wear are inevitable. During normal wear, the wear debris in the oil is small in size and increases slowly. However, when the mechanical equipment reaches the end of its service life or is about to fail, the amount of wear debris will increase dramatically and the size of the wear debris will also become larger and larger. Mechanical failures on board ships are serious and may even cause casualties and property damage. Therefore, research on detecting wear particles in the oil of large-scale marine mechanical equipment is of great significance for preventing failures and extending the service life of marine mechanical equipment. Existing detection methods are mainly divided into online monitoring and offline detection methods. The main offline detection methods include spectral analysis, iron spectrum analyzer, and laboratory microscope observation. Most of these methods require collecting oil samples in advance and then sending them to the laboratory for testing. Online monitoring can provide real-time detection information for mechanical equipment. Currently, online monitoring oil sensors are mainly divided into acoustic sensors, optical sensors, and electrical impedance sensors.

[0003] However, all of the aforementioned studies were conducted in a laboratory environment, without considering the impact of temperature changes in the sensor itself and the detection medium on the detection results during actual operation. The problem of sensor heating is mainly concentrated in the high-resistance coil, which will overheat under strong AC excitation, resulting in unstable detection coil characteristics. When the lubricating oil system of large mechanical equipment such as ships begins to operate, the lubricating oil needs to be heated to around 40°C in advance. After lubricating and cooling the key components, the lubricating oil temperature can reach 70°C or even higher. For low-resistance coils, the temperature of the detection coil will gradually converge to the temperature of the detection medium. The temperature difference may change the parameter characteristics of the coil, affecting the detection results. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide an oil detection sensor with a temperature compensation function.

[0005] The utility model is realized through the following technical solutions:

[0006] An oil detection sensor with a temperature compensation function includes a sensor detection unit, the sensor detection unit including a microfluidic chip, an excitation unit and a sensing unit; the microfluidic chip includes a microchannel, a substrate for fixing the microchannel and a model material; the sensing unit includes a solenoid coil and a capacitor arranged in parallel, the solenoid coil is sleeved outside the microchannel, and the excitation unit is electrically connected to the sensing unit via an insulated wire.

[0007] According to the above technical solution, preferably, the solenoid coil is arranged outside the microfluidic channel, and the solenoid coil is perpendicular to the microfluidic channel and concentric with the microfluidic channel.

[0008] According to the above technical solution, preferably, the number of turns of the solenoid coil is 100-200 turns, and the diameter of the microchannel is 7-11 mm.

[0009] According to the above technical solution, preferably, the capacitor is a ceramic capacitor with a capacitance of 0.1-0.3 μf.

[0010] According to the above technical solution, preferably, the excitation unit is a waveform generator, which is used to apply high-frequency alternating current excitation to the solenoid coil.

[0011] According to the above technical solution, preferably, the substrate is made of glass and is located below the microchannel, the model material is polydimethylsiloxane or polymethyl methacrylate, and the model material is cast outside the microfluidic chip and the sensing unit.

[0012] According to the above technical solution, preferably, it further includes a signal conditioning circuit electrically connected to the sensor detection unit, and the signal conditioning circuit includes a differential amplifier, a lock-in amplifier, an operational amplifier and a bandpass filter.

[0013] The beneficial effects of the utility model are:

[0014] This utility model boasts the advantages of high speed, high precision, and low cost. It can quickly, accurately, cost-effectively, and maintenance-freely detect contaminants in lubricating grease. By detecting and analyzing metal particles in the oil, it can determine the wear of mechanical equipment and prevent major mechanical equipment failures. Furthermore, the device is portable, easy to use, and has a wide range of applications. It also meets the requirements of actual oil testing environments and reduces the impact of temperature on test results, making it highly valuable for application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a three-dimensional structural diagram of the utility model.

[0016] Figure 2 It is a schematic diagram of the use principle of the utility model.

[0017] Figure 3 It is a circuit connection diagram of the utility model.

[0018] In the figure: 1. Substrate; 2. Model material; 3. Solenoid coil; 4. Microchannel; 5. Capacitor; 6. Precision resistor; 7. U-shaped tube; 8. Microfluidic chip; 9. Abrasive; 10. Water bath; 11. Oil. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the technical solution of the utility model, the utility model is further described in detail below with reference to the accompanying drawings and the best embodiment. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without making any creative work shall fall within the scope of protection of the utility model.

[0020] In the description of the utility model, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as a limitation on the utility model.

[0021] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "installed," "disposed," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0022] Example 1: As shown in the figure, the present invention includes a sensor detection unit, which includes a microfluidic chip 8, an excitation unit, and a sensing unit. The microfluidic chip 8 includes a microchannel 4, a substrate 1 for fixing the microchannel 4, and a model material 2. The sensing unit includes a solenoid coil 3 and a capacitor 5, wherein the coil and capacitor 5 are arranged in parallel, connected in parallel, and electrically connected to a precision resistor 6. The solenoid coil 3 is sleeved outside the microchannel 4. The excitation unit is electrically connected to the sensing unit via an insulated wire. In this example, the excitation unit is preferably a waveform generator for applying high-frequency AC excitation to the solenoid coil 3.

[0023] Among them, the solenoid coil 3 is set outside the microchannel 4, the solenoid coil 3 is perpendicular to the microchannel 4, and is concentric with the microchannel 4. In this example, the solenoid coil 3 is preferably a multi-layer winding coil, which is made of enameled wire. The inner diameter of the coil is 8-12mm, the diameter of the enameled wire is 0.05-0.07mm, the number of turns is 100-200 turns, the diameter of the microchannel is 7-11mm, and the capacitor 5 is a ceramic capacitor 5 with a capacitance of 0.1-0.3μf. The capacitor 5 is connected in parallel with the solenoid coil 3 to form an LC resonant circuit, which has the effect of eliminating the common mode rejection ratio. It can detect both high-frequency signals and low-frequency signals well. The LC resonant circuit has a very large impedance at the resonant frequency, which can effectively and selectively amplify differential mode signals, while showing high impedance to common mode signals with mismatched frequencies, thereby achieving the effect of suppressing common mode noise.

[0024] Meanwhile, in this example, the substrate 1 is preferably made of glass and is located below the microchannel 4. The model material 2 is preferably polydimethylsiloxane or polymethyl methacrylate, and the model material 2 is cast outside the microfluidic chip 8 and the sensing unit.

[0025] In addition, the present application also includes a signal conditioning circuit electrically connected to the sensor detection unit. The signal conditioning circuit includes a differential amplifier, a lock-in amplifier, an operational amplifier, and a bandpass filter, and transmits the signal to the computer via the data acquisition card. The signal conditioning circuit is prior art and is not described in detail in this embodiment.

[0026] In the oil 11 detection sensor, capacitor 5 provides temperature compensation by adjusting the circuit impedance to offset temperature-induced changes in the coil's conductivity. Furthermore, it forms an LC resonant circuit in parallel with solenoid coil 3, suppressing common-mode noise and maintaining a stable signal amplitude. Together with the signal processing circuitry, this ensures the sensor can accurately detect wear particles 9 in oil 11 at varying temperatures.

[0027] Example 2: Based on the above Example 1, the present application further discloses a preferred embodiment of an oil 11 detection sensor with a temperature compensation function, specifically comprising the following steps:

[0028] Step S1, fixing the microchannel in the middle of the U-shaped tube 7, and placing the U-shaped tube 7 in a water bath 10 for heating;

[0029] Step S2, the oil 11 to be tested flows into one side of the U-shaped tube 7 and flows through the detection unit;

[0030] Step S3, applying high-frequency alternating current excitation to the detection unit, and changing the sensor performance by changing the water bath heating temperature;

[0031] Step S4: The real-time signal is transmitted to the data processing and analysis unit through the signal conditioning circuit, and finally transmitted to the computer to observe the change of the inductance signal and realize the temperature compensation function;

[0032] In step S5, the oil 11 after detection flows into the oil storage tank for subsequent use.

[0033] This utility model boasts the advantages of high speed, high precision, and low cost. It can quickly, accurately, cost-effectively, and maintenance-freely detect contaminants in lubricating grease. By detecting and analyzing metal particles in the oil, it can determine the wear of mechanical equipment and prevent major mechanical equipment failures. Furthermore, the device is portable, easy to use, and has a wide range of applications. It also meets the requirements of actual oil testing environments and reduces the impact of temperature on test results, making it highly valuable for application and promotion.

[0034] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An oil detection sensor with temperature compensation function, characterized in that: It comprises a sensor detection unit, wherein the sensor detection unit comprises a microfluidic chip (8), an excitation unit and a sensing unit; The microfluidic chip (8) includes a microchannel (4), a substrate (1) for fixing the microchannel (4), and a model material (2); the sensing unit includes a solenoid coil (3) and a capacitor (5) arranged in parallel; the solenoid coil (3) is sleeved outside the microchannel (4); and the excitation unit is electrically connected to the sensing unit via an insulated wire.

2. The oil detection sensor with temperature compensation function according to claim 1, characterized in that: The solenoid coil (3) is sleeved outside the microchannel (4), and the solenoid coil (3) is perpendicular to the microchannel (4) and concentric with the microchannel (4).

3. The oil detection sensor with temperature compensation function according to claim 2, characterized in that: The number of turns of the solenoid coil (3) is 100-200 turns, and the diameter of the microchannel is 7-11 mm.

4. The oil detection sensor with temperature compensation function according to claim 1, characterized in that: The capacitor (5) is a ceramic capacitor (5) with a capacitance of 0.1-0.3 μf.

5. The oil detection sensor with temperature compensation function according to claim 1, characterized in that: The excitation unit is a waveform generator, which is used to apply high-frequency alternating current excitation to the solenoid coil (3).

6. The oil detection sensor with temperature compensation function according to any one of claims 1 to 5, characterized in that: The substrate (1) is made of glass and is located below the microchannel (4). The model material (2) is polydimethylsiloxane or polymethyl methacrylate, and the model material (2) is cast on the outside of the microfluidic chip (8) and the sensing unit.

7. The oil detection sensor with temperature compensation function according to claim 1, characterized in that: It also includes a signal conditioning circuit electrically connected to the sensor detection unit, and the signal conditioning circuit includes a differential amplifier, a lock-in amplifier, an operational amplifier and a bandpass filter.

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