Design And Control Of A High Speed Wire Clamp For Micro Device Packaging

As a key part of the micro device packaging equipment, the wire clamp directly affect the quality and efficiency of packaging, thus the research of novel wire clamp with high speed is extraordinarily necessary to the academic and practical application. For the purpose of improving the efficiency and quality of micro device packaging, a new wire clamp with high speed has been presented. The working principle, statics and dynamics characteristics and the clamping force measurement have been studied systematically. The characteristic experiments and control experiments are performed using a platform constructed by ourselves. Main research works are shown as below:A new high speed wire clamp driven by a piezoelectric actuator has been developed. A two stage displacement amplification mechanism is proposed in the wire clamp, which makes the wire clamp have a larger output displacement. In order to realize the parallel motion of the clamp jaws, flexible parallelogram mechanism is applied to the wire clamp, which can effectively improve the quality of clamping wire and ensure the accuracy of the package.Based on the Pseudo-Rigid-Body Model methodology, the analysis of kinematics, statics and dynamics have been investigated; Moreover the displacement amplification, input stiffness, maximum equivalent stress and natural frequency have been proposed. The static and dynamic characteristics of the wire clamp have been studied by finite element analysis. The displacement amplification and stress distribution have been discussed by static analysis, and the modal shapes and natural frequencies are obtained through modal analysis. The analysis results provide the prerequisite for structure optimization design and control of the wire clamp.In the light of bending deformation theory of flexible beam,a strain type force sensor is designed to measure the clamping force; Moreover the clamping force measurement and calibration principle have been studied. Based on the calibration principle, the force sensor calibration has been completed through the experiment.The experimental stage of the wire clamp has been set up and the experiments have been conducted. The results of clamping experiment reveal that the clamp jaws can realize parallel motion and stably clamp wires with different diameters; the displacement amplification has been measured and the hysteresis relationship between output displacement and driving voltage have been studied through open loop displacement experiment. The PI control experiment of displacement and force are conducted, and the results show that the wire clamp has good motion characteristics and can reach the packaging requirements.