The Study And Design Of The Automatic Control System Of Multi-Technique Metallographic Cutting Machine

Modern machine manufacture has undergone a huge change and automatic, optimization, integration, intelligentization and exactitude are the trends of its development. Metallographic sampling device which is a branch of modern machine manufactures has making for semi-automatic and automatic from handwork gradually.Metallographic technology has developed so rapidly that metallographic cutting machines have gained great progress as metallographic sampling devices. The sampling devices based on the microprocessor are the representatives of the advanced technique of the metallographic devices. By the combination of hardware and software and the increase of soft cutting-methods, metallographic samplings with high accuracy and performance, excellent reappearance have been gained which the hand work can not do.This paper makes use of the combination of software and hardware to achieve the control of the machine. A single-chip microcomputer is used to control the stepping motors and DC motors to achieve the control of the step-advance and rotation of the falchion. Multi-technique control and the divided technique under different states can be achieved by the switch of the buttons, such as stop/start, hand/auto and pause. So, it will enhance the accuracy and the quality of the samples because that a photo electricity-coder is used to measure the speed of rotation, PID algorithm and PWM (pulse width modulation) are introduced to modulate the speed of the motor instantly. The transmission of the dates between epigynous machine and hypogyny-machine is achieved via the popular interface-USB. The interface is written in Vc-H-6.0 and the program of the hypogyny-machine is written in assemble language. In order to find a proper and a correct way to control the stepping motor, this paper also studies the relationship between its frequency and speed.