Numerical control (NC) technology refers to the use of digital instructions composed of numbers, words and symbols to realize the action control of one or more mechanical equipment. Numerical control generally uses general or special purpose computer to realize digital program control, so numerical control is also called computer numerical control, referred to as CNC, foreign countries are generally called CNC, rarely use the concept of NC.
It usually controls mechanical quantities such as position, angle and speed, as well as switching quantities related to the flow direction of mechanical energy. The generation of numerical control depends on the appearance of data carrier and binary data operation. In 1908, the perforated sheet metal interchangeable data carrier came out; at the end of the 19th century, the control system with paper as the data carrier and auxiliary functions was invented; in 1938, Shannon carried out rapid data calculation and transmission at the Massachusetts Institute of technology, laying the foundation of modern computer, including computer digital control system. Numerical control technology is closely combined with machine tool control. In 1952, the first CNC machine tool came out, which became an epoch-making event in the history of world machinery industry and promoted the development of automation.
Now, the numerical control technology is also called the computer numerical control technology (CNC), at present it is using the computer to realize the digital program control technology. In this technology, the computer can control the movement track of the equipment and the operation sequence logic of the peripheral equipment according to the control program stored in advance. Because the numerical control device composed of hardware logic circuit is replaced by computer, all kinds of control functions such as storage, processing, operation and logic judgment of input operation instructions can be realized by computer software, and the micro instructions generated by processing are transmitted to the servo driving device to drive the motor or hydraulic actuator to drive the equipment.
Numerical control technology is the technology that uses digital information to control the mechanical movement and working process. Numerical control equipment is the mechatronics product formed by the penetration of new technology represented by numerical control technology into traditional manufacturing industry and emerging manufacturing industry, namely the so-called digital equipment, such as numerical control machine tools. Its technology involves many fields
(1) Mechanical manufacturing technology;
(2) Information processing, processing and transmission technology;
(3) Automatic control technology;
(4) Servo drive technology;
(5) Sensor technology;
(6) Software technology, etc.
Numerical control technology and equipment is the enabling technology and the most basic equipment for the development of new high-tech industries and cutting-edge industries. CNC technology is widely used in information industry, biological industry, aviation, aerospace and other national defense industries all over the world in order to improve manufacturing capacity and level, and improve market adaptability and competitiveness. Industrial developed countries also list CNC technology and CNC equipment as national strategic materials, not only vigorously develop their own CNC technology and industry, but also implement blockade and restriction policies on China’s “high-end” CNC key technology and equipment. Therefore, it has become an important way for developed countries in the world to develop advanced manufacturing technology with numerical control technology as the core to accelerate economic development and improve comprehensive national strength and national status.