input / output interface and so on. The latest generation of CNC system also includes a communication unit; it can complete the CNC, PLC's internal data communications and external high-order networks. Servo drive system including servo drives and motors. Position measuring system is mainly used grating, or circular grating incremental displacement encoder.
CNC system hardware from the NC device, input / output devices, drives and machine logic control devices, electrical components, between the four parts through the I / O interface to interconnect.
Numerical control device is the core of CNC system, its software and hardware to control the implementation of various CNC functions.
The hardware structure of no device by CNC installations in the printed circuit board with infixing pattern can be divided into the big board structure and function module (small board) structure; Press CNC apparatus hardware manufacturing mode, can be divided into special structure and personal computer type structure; Press CNC apparatus in the number of microprocessor can be divided into single microprocessor structure and many microprocessor structure.
(1)Large panel structure and function templates structure
1) Large panel structure
Panel structures CNC system CNC equipment from the main circuit board, position control panels, PC boards, graphics control panel, additional I / O board and power supply unit and other components. The main circuit board printed circuit board is big; the other circuit board is a small plate, inserted in the large printed circuit board slot. This structure is similar to the structure of micro-computer.
2) Function templates structure
(2)Single-microprocessor structure and mulct-microprocessor structure
1) Single-microprocessor structure
In a single-microprocessor structure, only a microprocessor to focus on control, time-sharing deals with the various tasks of CNC equipment.
2) melt-microprocessor structure
With the increase in numerical control system functions, CNC machine tools to improve the processing speed of a single microprocessor CNC system can not meet the requirement; therefore, many CNC systems uses a multi-microprocessor structure. If a numerical control system has two or more microprocessors, each microprocessor via the data bus or communication to connect, share system memory and common I / O interfaces, each processor sharing system Part of the work, which is multi-processor systems.
CNC software is divided into application software and system software. CNC system software for the realization of various functions of the CNC system, the preparation of special software, also known as control software, stored in the computer EPROM memory. CNC Systems feature a variety of settings and different control schemes, and their system software in the structure and size vary widely, but generally include input data processing procedures, computing interpolation procedures, speed control procedures, management procedures and diagnostic procedures.
(1)Input data processing procedures
It receives input part program, the standard code, said processing instructions and data