Overview
The numerical control device is a special electronic computer that controls the machine tool and completes the automatic processing of parts. It receives digitized part drawings and process requirements and other information, performs interpolation operations according to a certain mathematical model, and uses the results of the calculations to control the speed and position of each movement coordinate of the machine tool in real time to complete the processing of the parts.
The generation of the numerical control system
The numerical control system is a digital control system, abbreviated as (Digital or Numerical Control System), which was composed of hardware circuits in the early days, called hardware numerical control (Hard NC) After the 1970s, hardware circuit components were gradually replaced by dedicated computers called Computerized Numerical Control (CNC). A computer numerical control system is a system that uses a computer to control processing functions and realize numerical control. The CNC system executes part or all of the numerical control functions according to the control program stored in the computer memory, and is equipped with a dedicated computer system with an interface circuit and a servo drive device. The motion control of one or more mechanical equipment is realized by using digital instructions composed of numbers, characters and symbols. It usually controls mechanical variables such as position, angle, and speed, and switch variables.
The development of numerical control system
With the progress of science and technology, especially the development of microelectronics and computer technology, numerical control systems continue to obtain the latest hardware and software resources and develop rapidly. Every well-known CNC system manufacturer, on average, a new model of CNC system product is born every three years. The application of CNC machine tools has also been applied to various occasions from solving difficult parts processing, batch parts automatic production, to entering the home workshop, and constantly putting forward new requirements on the hardware and software of the CNC system. It is required to have an open structure CNC system, adapt to technological development and functions developed by users themselves. Some developed countries and regions, such as Europe, the United States, Japan, etc., have successively carried out the research and development of the open structure CNC system.
Open structure CNC system
The basic structure of the open CNC system includes a hardware platform, a software platform, a user-extensible hardware and software space, and an application development environment.
Hardware platform
Supplied by the CNC system manufacturer, or select a general standard module, but its configuration can be selected by the user in a larger range, such as the number of control axes, control mode , Various external equipment, etc.
Software platform
Provided by the CNC system manufacturer or CNC software developer, it is the core software of the system, that is, the basic software of CNC and PLC. It also provides good users The environment for developing application software.
Application software: On the basis of the hardware and software platform provided by the CNC system manufacturer, the user develops special software and hardware to realize the control function required by the user.
Concluding remarks
The rapid development and wide application of computers (PersonalComputer--PC) provides a way for us to develop PC-based (PCBased) and open-structure CNC systems. Effective way. From the early 1980s as an office computer, the PC has developed into a mainstream computer in various fields and has been widely used in the field of process control and automation. The main frequency of the PC has reached 450MHz, which can meet the requirements of various CNC high-speed real-time control systems, rich software resources, such as DOS, Windows, C language and other development tools, and a large number of available external devices, such as CRTs, flat panel displays, and CD-ROMs. Drive, floppy disk drive, hard drive, keyboard and other hardware support. The integration of PC chips is getting higher and higher, and the output of PCs is increasing year by year, all of which provide conditions for PC-based CNC systems to shrink in size and have a high performance-price ratio. Because PC-based CNC systems make full use of PC’s With hardware and software resources, new technologies can be continuously adopted following the development of PCs.
From the use of Intel80286, 80386, to PentiumⅢ, the operating system has also developed from DOS to Windows, etc., so PC-based CNC systems are getting faster and faster development and applications.