电容薄膜真空计用金属膜片电容传感器设计

Design of Metal Diaphragm Capacitance Sensor for Capacitive Diaphragm Vacuum Gauge

金属膜片电容传感器是高精度电容薄膜真空计的关键部分。为满足其国产化需求,以国内研发的某镍基合金膜片材料为基础,研究电容薄膜真空计用金属膜片电容传感器。首先,基于通用有限元分析软件,建立金属膜片电容传感器中感应膜片的计算模型;然后,采用非线性大挠度理论对不同预应力下的感应膜片变形进行计算,并与理论计算结果进行对比,对比结果表明,该计算模型具有较高精度;最后,分析预应力与感应膜片非线性误差关系,并对影响电容薄膜真空计测量特性的预应力、感应膜片与固定极板的初始极距等关键参数进行设计,以满足高精度真空测量的要求。

Metal diaphragm capacitance sensor is the key part of high precision capacitance diaphragm vacuum gauge.In order to meet the domestic demand,a metal diaphragm capacitive sensor for capacitive diaphragm vacuum gauge was studied based on a nickel based alloy diaphragm material developed in China.Firstly,based on the general finite element analysis software,the calculation model of the induction diaphragm in the metal diaphragm capacitance sensor is established;Then,the nonlinear large deflection theory is used to calculate the deformation of the induction diaphragm under different pre-stressing forces,and the comparison with the theoretical results shows that the calculation model has high accuracy;Finally,the nonlinear error relationship between pre-stress and induction diaphragm is analyzed,and the key parameters such as pre-stress,initial electrode distance between induction diaphragm and fixed plate which affect the measurement characteristics of capacitive diaphragm vacuum gauge are designed to meet the requirements of high-precision vacuum measurement.