Research On Accuracy Control Technologies Of Complex Diamond Manufacturing Special Equipment

The development capability for CNC machine tools is directly related to the equipment manufacturing capacity of nations, and the accuracy is an important index to measure a CNC machine tool's performance. Based on in-depth studying the accuracy control technology, this thesis proposed an accuracy control technology for the jig needle bar in the complex diamond manufacturing special equipment based on FEA, tolerances optimization technique based on sensitive error analysis theory for the complex diamond manufacturing special equipment and error compensation function using PLC control system, those technologies were applied to practice very well.In the first chapter, the electromechanical integration and NC machine tools were introduced briefly, and CNC characteristics were summarized, then the research present situation and main tasks of CNC machine tools' accuracy control in domestic and overseas were outlined .In addition, the application background of the complex diamond manufacturing special equipments was explained, the problems in diamond manufacturing tools were analyzed in detail. Moreover, the accuracy control problems what need to be solved in the complex diamond manufacturing special equipment were given.In the second chapter, aiming at solving the rigid problem of the jig needle bar, an accuracy control method based on FEA was put forward. The force model of the jig needle bar in the process of grinding diamonds were analyzed, and the calculation formula of grinding force was established. After meshing the jig needle bar model, the influence of supporting point to the bar's rigid was analyzed, then optimized the supporting point's position to achieve the purpose of controlling the accuracy.In the third chapter, in order to improve precision of tolerance design, tolerance optimization technique based on sensitive error analysis theory for the complex diamond manufacturing special equipment was proposed. The basic method of sensitive error analysis was introduced, and the topological structure of the component in the complex diamond manufacturing special equipment was established using multi-body system theory, then error model of the complex diamond manufacturing special equipment was set up based on the low sequence body arrays theory, moreover, the method of sensitive error analysis was given.In the fourth chapter, to point against the limitation to improve the accuracy of the complex diamond manufacturing special equipment by error precaution, the error compensation technique by using PLC control system was analyzed. Then the principle and method of error compensation was researched in-depth, and also the steps and notes of error compensation by using the function of opposite clearance error compensation and electronic gear were given.In the fifth chapter, the accuracy control techniques what were proposed in the second chapter to forth chapter were applied to the accuracy control scheme in the complex diamond manufacturing special equipment. Firstly, the right jig needle bar supporting point was chosen and the deflection distribution figures and the drawing of jig body were given. Secondly, the sliding table's tolerances were optimized based on the sensitive error analysis theory. Lastly, error compensation of the transmission parts was executed by using the PLC control system.In the sixth chapter, the research results of this thesis were summarized, and the future research direction are expected.