Inductive displacement sensor and displacement measuring method thereof

Abstract

The invention discloses an inductive displacement sensor and a displacement measuring method thereof for detecting displacement of a metal material. The inductive displacement sensor is designed to include a precision high-speed inductive measuring part with adjustable exciting signals and a displacement calculation part according to inductive changes. The inductive displacement sensor comprises amicrocontroller; the microcontroller comprises a digital-analog converter, an analog-digital converter and a PWM controller. The microcontroller outputs the excitation signals according to the digital-analog converter, and the amplitude and the frequency of the excitation signals can be adjusted by changing the output mode. The excitation signals are loaded on a four-arm bridge with an inductiveprobe. Two output signals of the bridge are uniformly divided into four parts, and each part includes a ninety-degree phase difference; uniform division is achieved by adopting PWM signals for controlling an analog switch. Sliding averaging and sampling are performed on the output eight parts of signals; according to the sliding average value of the eight parts of signals, the inductive componentof the inductive probe can be calculated, and the displacement can be calculated according to component changes.

Description

technical field [0001] The invention relates to the technical field of displacement sensors, in particular to an inductive displacement sensor and a displacement measurement method thereof. Background technique [0002] There are two types of displacement sensors: contact type and non-contact type. Among them, it is difficult for contact type displacement sensors to measure objects moving at high speed. Displacement sensor, eddy current displacement sensor, etc. The eddy current displacement sensor can indirectly measure the displacement change according to the inductance change, loss change, and excitation frequency change of the coil caused by the eddy current as the induction quantity. Compared with displacement sensors of other principles, eddy current sensors have the characteristics of no blind area, convenient installation, large measuring range, and insensitivity to surface oil pollution, etc., and are widely used. The sensor involved in the invention belongs to a ...

AI Technical Summary

Problems solved by technology

While modifying the frequency of the excitation signal, it is necessary to modify multiple parameters of the sensor, which is difficult to complete in the application field

[0009] At present, the linearity of the inductance probe is not high, and it is generally corrected in the production stage.

The measuring range of the probe is fixed, reducing application flexibility

[0010] In summary, there is still a lack of an inductive displacement sensor with high precision, high frequency response, adjustable excitation signal, on-site setting of the measurement range and linear correction

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