Servo system is an important part of CNC machine tools for the realization of CNC machine tool feed servo control and spindle servo control. The role of the servo system is to accept the instructions from the numerical control device information, after power amplification, shaping processing, converted into machine tool parts of the linear or angular displacement movement. As the servo system is the last part of CNC machine tools, its performance will directly affect the accuracy and speed of CNC machine tools and other technical indicators, therefore, the CNC machine tool servo drive, requires a good fast response performance, accurate and sensitive tracking CNC Issued by the digital command signal, and faithfully from the NC device instructions to improve the dynamic tracking characteristics of the system and static tracking accuracy.
The servo system consists of two parts: drive device and actuator. The driving device is composed of a spindle driving unit, a feed driving unit and a spindle servo motor and a feed servo motor. Stepper motors, DC servo motors and AC servo motors are commonly used as drive devices.
The measuring element detects the actual displacement value of the coordinate axes of the CNC machine and enters it into the numerical control device of the machine through the feedback system. The numerical control device compares the actual displacement value of the feedback with the command value and outputs the set value to the servo system The required displacement command.