Hardware Circuit Design And Program Development Of WEDM Machine Tool Motion Control System

Wire Electrical Discharge Machining(WEDM)machine tool has many advantages,such as simple mechanical structure,low manufacturing cost and good workmanship.So it has been widely used in practical engineering.However,the research on WEDM CNC system in China is still at a low level.There are some problems in WEDM machine tools in China,such as low intelligence,low automation and lack of flexibility,which seriously hinder the further development of WEDM machine tools in application scope,function expansion and processing accuracy.Motion control system is the core part of WEDM CNC machine tool,which directly affects the performance of CNC system,machine tool processing accuracy and processing efficiency.Therefore,it is of great practical significance to study the motion control system suitable for WEDM machine tool in China.This paper focuses on the following aspects of the motion control system based on the mode of "PC + Motion Control Board" in Windows system:(1)The technological experiments of WEDM are carried out,and the effects of parameters on the warping deformation of thin-walled parts in WEDM are preliminarily studied,which lay the experimental foundation for the formulation of motion control system.(2)The research status of motion control system of WEDM machine tool is analyzed,the overall scheme of motion control system is formulated,and the hardware circuit working platform is planned.(3)According to the overall scheme of the motion control system,the circuit schematic diagram of the motion control card is designed and the PCB card is made.It includes power supply circuit,CPLD configuration circuit(clock circuit,JTAG circuit,etc.),threshold voltage control circuit,input and output interface circuit and power-off protection circuit.(4)The Motion control system communicates between upper and lower computers through serial port,the program is compiled and burned it into CPLD controller,sends pulse signal of CPLD output to driver,then controls stepper motor,which realizes the control running direction,speed and running distance of stepper motor.(5)According to the scheme of motion control system,a power-off protection functional circuit is designed.Through program simulation and hardware test,the scheme can store and read data between CPLD and RAM correctly and steadily,and can realize power-off protection.In order to improve the development and flexibility of the motion control system of WEDM machine tool,a more perfect motion control scheme is formulated,and the corresponding modules are designed and programmed.Experiments show that the project has high practical value,which greatly promotes the research process of WEDM CNC system in China.