A capacitance measuring device for a laser height controller

Abstract

The embodiment of the invention provides a laser height regulator capacitance measuring device. A charge and discharge network is used to carry out periodic charging of a calibration capacitor and a capacitor to be measured through a first resistor and a second resistor. The calibration capacitor and the capacitor to be measured are periodically discharged through a first diode and a second diode. Through a measurement calculation unit, the average deviation value of the voltage of two ends of the calibration capacitor and the voltage of two ends of the capacitor to be measured is measured, the capacitance value of the capacitor to be measured is calculated and obtained according to the relation between the average deviation value and the capacitance value of the calibration capacitor and the capacitance value of the capacitor to be measured. Thus instable measurement caused by an oscillator oscillation frequency is prevented, and a technical problem that an existing frequency modulation measuring circuit is vulnerable to external interference due to the large change of the oscillator oscillation frequency in measuring a capacitor is solved.

Description

technical field [0001] The invention relates to the field of laser height controllers, in particular to a capacitance measuring device for laser height controllers. Background technique [0002] In the process of laser cutting, in order to ensure the cutting quality, the laser focus should generally be located at 1 / 3 of the thickness below the surface of the workpiece to be processed. However, due to many reasons, the position of the laser focus will deviate from the ideal position, causing the laser cutting head to The distance between the workpiece and the workpiece is variable and difficult to measure. Therefore, it is necessary to monitor the capacitance value between the laser and the processed plate object in real time during the cutting process, and then determine the corresponding Z-axis position relationship of the laser head and adjust it in real time. [0003] see figure 1 , the existing frequency modulation measurement circuit can realize the measurement of capa...

AI Technical Summary

Problems solved by technology

[0015] The embodiment of the present invention provides a capacitance measurement device for a laser height controller, which is used to solve the technical problem that the existing frequency modulation measurement circuit is susceptible to external interference due to large changes in the oscillation frequency of the oscillator when measuring capacitance.

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