Design And Experimental Study Of Wire Electrical Discharge Grinding Mechanism

A set of Wire Electro-discharge Grinding(WEDG) mechanism with campact structure and multi-function,which can change its wire electrode modules conveniently,is designed for on-line machiningof micro-cylindrical and conical electrodes of high accuracy efficiently.To know well the characteristics of process of machining of micro-electrode, research status homeand abroad has been investigated.To improve the efficiency and accuracy of on-line machining ofmicro-electrode, process plan combining self-drilled holes and WEDG is put forward.Based ofdesigning and characteristics of different mechanisms, designing method of WEDG mechanism withcampact structure and multi-function is proposed.To provide theoretical basis for reasonable design of WEDG mechanism,factors affectingperformance of WEDG mechanism and path of wire electrode are analysed in this paper. Significancesof constant speed and tension control are also expounded. Vibration states and stiffness of keysupporting parts are calculated.To maintain contast tension control, a unit providing friction with plates is designed.Method thatcombining stepper motor,torque motor and unit providing friction with plates is put forward as well.Based on the principle of different facilities having the same center of rotation, a compact guide unitwith high rotational accuracy is designed. Accordingly the stability of moving of wire electrode isenhanced and the dimension of WEDG mechanism is decreased. According to the principle ofadjusting the angular position of wire electrode and tool electrode, a wire-moving agency which canchange cylindrical electrode unite and cone electrode unite conveniently is designed.Detailed auxiliary of WEDG mechanism is optimized after finishing preliminary experiments. Toobserve the status of discharge grinding process, microscopic observation equipment is introduced. Toavoid the situation that mixture of different working fluids can impact the final processing quality,auxiliary operating fluid sump is added. To improve the stability of moving of wire electrode, guideblock which can track wire electrode is designed. Adjusting platform is introduced to ensure the angularposition relations between micro-electrode and workpiece.Experiments of maching micro cylindrical and conical electrodes has been made.the stability of micro cylindrical wire going mechanism is judged by consistency of the electrode diameter, accuracyof diameter and the surface quality. Likely the stability of cone electrode wire going mechanism is alsoadjused by the linear of cone bus bar, symmetry of cone angle and surface quality. Experiments showprocess plan of compact andmultifunctional WEDG mechanism which can change cylindricalextrode unite and conical electrode unite conveniently is reasonable. WEDG mechanism can meet therequirement of online maching of different tool electrodes.