基于激光衍射的拉丝模具孔径测量系统设计

Design of Aperture Measurement System for Wire Drawing Die Based on Laser Diffraction

针对拉丝模孔径越来越小的趋势,目前的孔径测量就存在诸多问题。为了提高微小孔拉丝模的孔径测量精度,系统创新地将旋转测量法和夫琅和费衍射相结合,在测量过程中,不断旋转拉丝模中心轴,在CCD上形成不同形状的类圆孔,利用类圆孔和旋转角度之间的函数关系实现拉丝模孔径参数的测量。测量系统由机械、光学成像、数据采集与处理等4部分构成,系统测量精度可以达到0.01 mm。实验结果表明该系统可靠性好、精度高。

In view of the decreasing trend of wire drawing die aperture, the present methods of measuring exist many problems. In order to improve the measurement precision of wire drawing die aperture of micro hole, the spin measurement and Fraunhofer diffraction have been combined in this system. In the process of measurement, the wire drawing die center axis is rotated continuously so as to form elliptical holes with different shape on CCD. Various parameters of wire drawing die are measured using the function relationship between the elliptical holes and the angles of each part and the central axis. The measurement system is composed of mechanical,optical imaging, data acquisition and processing. Finally the results of the measurement chart is given. The measurement precision can reach0.01 mm. The experimental results show that the system has good reliability, high precision.