Control System Of High Precision Plating Production Line For IC Lead Frame Based On Machine Vision

With the development of science and technology, the electronic products update faster and faster, which contributes to the increasing demands of IC chips such as transistors and other electronic components. The lead frame is the skeleton of electronic components, and its demand is also increasing. The lead frame is a connector between IC and PCB. The manufacturing of IC lead frame is the upstream of IC industry.The research topic, in reference to domestic and abroad roll-plating production line, designs and applies a high-precision control system for IC lead frame plating product line based on machine vision. The applications of machine vision inspection, servo positioning control, frequency control, ultrasonic distance measurement and other technologies in high-precision rolling IC lead frame plating production line is introduced. The research solves the existing problems of the traditional plating product line that use PLC & Servo control system.The control system advantages lie in:(1) Based on machine vision inspection technology, the barycenter of the positioning hole is measured, the measured value with a target value comparison and calculate the position error, and then timely by the servo system to compensate for errors, in order to achieve precise positioning. Silver plated precision, from the ± 8MIL(1MIL = 0.0254mm) up to now ± 4MIL.(2) Based on ultrasonic distance measurement and frequency control. Through ultrasound to measure the buffer wheel height of before and after and calculate the production speed rate, then through PLC control inverter, timely adjustment of production speed to prevent speed variation is too large impact on production processes, in order to achieve production process stability.(3) Through effective technology integration and optimization algorithm, we developed a new roll-IC lead frame plating control system, the more traditional control system with high precision, high speed, non-contact detection merit and so on.Production practice shows that IC lead frame product line use the new control system, can thoroughly solve the problem of injuring products by the positioning pins. It meanwhile provides a position error compensation function, i.e. when the position deviation is too large and beyond the compensation position, it can timely remind the operator to deal with, which avoids a large number of scrap due to the error-positioning.