Study Of Fundamental Theory On The Hybrid-driven Drawing Press And Precision Press

The hybrid-driven press is a new type of machine system, which is to combinethe motion of a large uncontrollable constant speed motor with a small controllableservomotor via a two-DOF mechanism, where, the constant speed motor providesmain torque and motion requirements, while the servomotor contributes tomodulations on this motion. This kind of mechanical system not only has advantagesof classical mechanical system, but also is controllable and has great flexibility. So,without changing the geometric parameters of the system, only through adjusting thetrajectory of servomotor displacement, the same hybrid-driven is able to meetdifferent requirements of pressing different products and materials. The choice of selecting a suitable type of mechanism is very critical to thehybrid-driven. Therefore, the analysis of singularity and mobility condition of a newtwo-DOF hybrid-driven mechanism is presented. On the basis of these, the kinematicanalysis of this mechanism is given. In addition, the optimum design of thehybrid-driven press for deep drawing is carried out through two major processes. Thegeometric parameters of mechanism is optimized first, based on which, theoptimization of the displacement trajectory of the servomotor is conducted. The theoretical research of hybrid-driven precision press mainly includes:(1)According to the properties of precision forging, a few examples of optimumdesign of hybrid-driven precision press are given, which include optimizing thegeometric parameters of the precision press and the motion trajectory of theservomotor; (2)The power distribution of the two motors is studied through analyzingdynamical static force of the system; (3) Based on Lagrange's formulation thedynamic model of two-DOF hybrid-driven mechanism is constructed. Then it islinked to dynamic models of the two dc motors controlled with PID, hence, thedynamic model of the whole system; (4)The dynamic equations are transformed into asystem of first order equations. Finally dynamic simulation is carried on throughsolving the equations by the fourth Runge-Kutta approach. At the end of the research, some suggestions are given for further studies andapplication of the hybrid-driven precision press.