Parallel-plate multi-electrode capacitance type oil level sensor

Abstract

The invention relates to a parallel-plate multi-electrode capacitance type oil level sensor which comprises a multi-electrode plate and a common-electrode plate, wherein the upper part of the multi-electrode plate and the upper end of the common-electrode plate are inserted into a protection box; a control circuit is arranged on the upper part of the multi-electrode plate and comprises a power supply circuit, a data acquiring and processing circuit and a signal output circuit; the power supply circuit is connected with a +12V power supply, the signal output circuit is connected with the input end of an oil meter; five measurement electrodes and one reference electrode are at least arranged on the middle and the lower part of the multi-electrode plate, and are respectively connected with the data acquiring and processing circuit of the control circuit; and a common electrode is arranged on the common electrode plate and is connected with the data acquiring and processing circuit of the control circuit. The parallel-plate multi-electrode capacitance type oil level sensor is capable of avoiding influence of a temperature to a dielectric constant of an oil material medium and accurately reflecting the quantity of oil remained in a reaction fuel tank, and is high in measurement precision and stable and reliable in work.

Description

technical field [0001] The invention relates to a sensor, in particular to a parallel plate multi-electrode capacitive oil level sensor for automobiles and motorcycles, and a multi-electrode capacitive oil level sensor. technical background [0002] The fuel level sensor is installed in the fuel tank of automobiles and motorcycles, collects the height information of the oil level in the fuel tank, and transmits it to the fuel gauge after being processed by the controller to indicate the remaining fuel in the fuel tank. At present, the fuel level sensor used in most automobiles is a float type variable resistance sensor. Although the structure is simple, it has poor precision, low reliability, and short service life. It cannot accurately measure the amount of oil in the fuel tank of the automobile. In order to overcome the shortcomings of traditional oil level sensors, some cars use capacitive oil level sensors, which can be divided into coaxial capacitive oil level sensors, ...

AI Technical Summary

Problems solved by technology

For example, the axial capacitive oil level sensor, due to the relatively closed space between the two capacitor plates, impurities will be deposited on the two plates after a period of use, which will affect the accuracy of the measurement; the parallel plate capacitive oil level sensor and the single plate comb capacitor Since the electrode of the oil level sensor is open, it will be washed by the oil in the fuel tank during use, and no impurities will be deposited on the plate. There will be a layer of oil attached to the surface of the electrode. Since the distance between the electrodes is very small, the attached oil layer will significantly change the capacitance value, causing measurement errors

Since the capacitive oil level sensor produces different capacitance values ​​according to the ratio of the air medium and the oil medium between the capacitor plates, but the dielectric constant of the oil medium is affected by temperature, no matter it is a coaxial capacitive oil level sensor, parallel Board capacitive oil level sensor or single board comb capacitive oil level sensor will be affected by this

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