角位移传感器膜电阻全自动激光修刻系统试验研究

摘要

Conductive plastic thin film resistor is the core structure of angular displacement sensor. It has a direct impact on the various output of sensor performance, which must rely on engraving to meet the requirements. As a new technology emerged in recent years, laser carving technology takes the advantage of accuracy, non-contact and rapidity to achieve very high accuracy and efficiency. Laser carving system is mainly composed of automatic focusing laser, automatic workpiece loading and unloading mechanism, rotary carved machine, resistance online detection circuit and industrial personal computer, etc. As the key of achieving rapid and high pre-cision trim, thin film resistance carving algorithm was based on the theory of discrete approximation correction to realize the automati-cally time-fixing control through the feedback voltage algorithm. Test results show that the laser carving system can achieve 0. 1% re-sistance trim precision and speed of 3 minutes for each membrane resistor.%导电塑料角位移传感器中的膜电阻是其核心结构，直接影响传感器的各种输出性能，必须依靠修刻才能满足要求。激光修刻技术是近几年出现的膜电阻修刻新技术，利用了激光微加工精准、非接触并快速的优势，能达到非常高的修刻精度和效率。激光修刻系统主要由带自动调焦激光器、工件自动装卸机构、回转修刻台、阻值在线检测电路和工控机等组成。膜电阻修刻算法是实现快速高精度修刻的关键，依据离散逼近修正理论，通过采用反馈电压算法实现系统的自动修刻控制，试验结果表明：激光修刻系统能达到0．1%的电阻修刻精度和3 min/个的修刻速度。