Study On Dynamic Characteristics Analysis And Application Of High Spot Closed Gripper Mechanism Of Press

This paper aimed at attacking and noise problem of high spot closed gripper mechanism in the running process, and made theoretical analysis and application research. The method of dynamic characteristics analysis was built, the dynamics characteristics of the example mechanism was analyzed, and the root cause of attacking and noise were disclosed for this mechanism. The improved ideal and method were presented. Finally, the method and process of mechanism's dynamic characteristics analysis were integrated, and the software was developed.The main work and results are as follows:(1) According to the particular movement of high spot closed gripper mechanism, the full method of dynamic characteristics was presented and built. It contained relative motion analysis, absolute motion analysis, dynamics of rigid body's analysis and elastodynamics analysis.(2) The current equation of mechanistic relative movement analysis was deduced and created by cubic spline interpolation. Then, according to mechanistic mater slave kinematics relation, the expression of mechanistic absolute movement analysis was set up. These provided theoretical basis of mechanistic dynamic characteristics analysis.(3) The real switching gripper position was hunted by computer one dimension hunting. The temporal and spatial law of switching gripper force was obtained by the switching gripper position. Then, stiffness stress model was created. The stressed analysis of the example mechanism was accomplished on the basis of this model. It is shown by analysis that the basic reason of attacking and noise problem is due to the violent variation of absolute acceleration.(4) Considering component elastic distortion, the mechanistic elastodynamics model was established by alternative principle of quality and elastic cell, and the example mechanism dynamic response was obtained on the elastodynamics model. It is indicated that component elastic distortion take a little influence for gripper force, make some influence for opened gripper and also affect the mechanistic dynamic performance, the coefficient of impact is2.1656.(5) Focused on above-mentioned problems, the modified path and method were put forward. Then, improved design and dynamic characteristics were executed for high spot closed mechanism by choosing movement rule curve with excellent motion performance. It is shown that the cycloid, quintic, and septennial motion laws are applied on the closed gripper stroke and the cycloid, quintic, septennial, and bi-harmonic are applied on the opened gripper stroke. These can make angular acceleration curve become smoothness and flat, take contact force and apiece joint force closed to slick. Therefore, the attacking and noise are reduced greatly, and the dynamic characteristic is ameliorated at the meantime. The coefficient of impact is from 1.1356 to 1.5524.(6) On the basis of above-mentioned analysis and design process, the method of dynamic characteristics and improved design were integrated by Matlab platform. Finally, the practical software was developed for meeting needs of enterprise.