Multi-blade capacitive angular displacement sensor

Abstract

The invention relates to a multi-blade capacitive angular displacement sensor which comprises a demodulation circuit and a sensitive structure. The demodulation circuit generates sine excitation signals to act on the sensitive structure; the sensitive structure returns capacitance change information to the demodulation circuit to furthermore obtain corner information. The sensitive structure comprises a stator and a rotor; the surface of the stator is provided with a guard electrode, an exciting electrode and a collection electrode; the innermost side and the outmost side of the stator surface are both provided with a guard electrode; the outside adjacent to an inner ring guard electrode is provided with an exciting electrode, and the outside of the exciting electrode is provided with a collection electrode. The rotor comprises a guard electrode, a coupling electrode and a sensing electrode; the innermost side and the outmost side of the rotor surface are both provided with a guard electrode; the outside adjacent to an inner ring guard electrode is provided with a coupling electrode, and the outside of the coupling electrode is provided with a sensing electrode. The collection electrode and the sensing electrode are opposite and form a measurement capacitor. The multi-blade capacitive angular displacement sensor can reduce measure errors caused by radial run-out.

Description

technical field [0001] The invention relates to a sensor, in particular to a split-lobe capacitive angular displacement sensor used in the fields of industrial automation control systems, instrumentation, and electronic product manufacturing. Background technique [0002] At present, spindle angular displacement information and angular velocity information are extremely important measurement parameters in industrial automation control systems, instrumentation, and electronic product manufacturing. Therefore, the development of inexpensive, high-precision, and high-dynamic angular displacement sensors is of great importance to industrial automation. There are many types of angular displacement measurement sensors with high precision, but there are disadvantages such as relatively large volume, complicated processing, high cost, harsh environmental requirements, and poor dynamic characteristics. [0003] The inductive angular displacement sensor has high precision, good temper...

AI Technical Summary

Problems solved by technology

[0002] At present, spindle angular displacement information and angular velocity information are extremely important measurement parameters in industrial automation control systems, instrumentation, and electronic product manufacturing. Therefore, the development of inexpensive, high-precision, and high-dynamic angular displacement sensors is of great importance to industrial automation. There are many types of angular displacement measurement sensors with high precision, but there are disadvantages such as relatively large volume, complicated processing, high cost, harsh environmental requirements, and poor dynamic characteristics.

[0003] The inductive angular displacement sensor has high precision, good temperature characteristics, and low installation requirements, but the processing is complicated, the cost is high, and it is sensitive to the electromagnetic environment; the capacitive angular displacement sensor has high stability, can be used for non-contact measurement, and has good dynamic response. Adapt to harsh environments, etc., has been considered by more and more people to be the most promising sensor

[0004] At home and abroad, there are many studies on capacitive sensors used to measure angular displacement, and great breakthroughs have been made: mainly focusing on the improvement of sensitive structures. The conventional sensitive structure is fan-shaped and split, and the ability to obtain angular displacement information is limited. Sensitivity is also limited by machining accuracy and the demodulation circuit is complex

Images