Design Of The Automatic Control System Of Metallographic Polishing Machine Based On CPLD

Nowadays, we are in the times of rapid developed information, automatic optimization, integration, intelligentize and exactitude have made modern machine manufacture undergone a huge change. And it is the trend of the development. Metallographic polishing device which is a branch of modern machine manufactures has making for half-automatic and automatic from handwork.Metallographic polishing machines are mainly used for the abrading and polishing of metallographic sample and various materials. They are used broadly in mechanism, metallurgy, aviation and so on. After the ninth decade in 20th century, metallographic technology has developed so rapidly that metallographic polishing machines have gained great progress as metallographic sampling devices.The overall system is mainly composed by two parts: control system and display system. The control system mainly controls two direct stepping motors and several related switches. The direct stepping motor is used to control the speed and press of the polishing machine. The display system mainly has two functions: input and display. You can input all the polishing related quantity through the keyboard, for instance: The time, the press, the velocity and so on. The display system shows the establishment polishing parameter before polishing and shows the monitoring parameter in the polishing process. The control system and the display system are in integrated component, so as to reduce the error code.The study is based on CPLD and QuartusⅡ.The controller designed with the method of software hardening and VHDL(a design description language used in IBM AS/400 processor).According to the designing course and the necessary function,the controller is divided into eight modules. Every module is described with VHDL,and then all the Programs would be compiled,simulated and tested. It takes modularized method to design the system,so it is,easy to be designed,maintained and extended.After the designing was finished,some experiments have been done,the results indicate that using CPLD as the automatic control of polishing machine has many advantages,for example,the program is criterion,the test of time sequence is facility,the modification of system is flexible,the hardware need not change on the whole .It is a new and efficient method in realizing the the automatic control system of metallographic polishing machine.