What is numerical control? What does numerical control technology include? How to learn CNC well

Numerical control technology, referred to as numerical control. It uses numbers.

A method of controlling machine tool movement and machining process with word information. A machine tool that uses numerical control technology to realize machining control, or a machine tool equipped with a numerical control system, is called a numerical control (NC) machine tool. Numerical control system includes: numerical control device, programmable controller, spindle driver and feed device. CNC machine tools are highly integrated products of machinery, electricity, liquid, gas and light. In order to control the machine tool, it is necessary to describe the relative motion between the tool and the workpiece with geometric information, and to describe some process parameters that the machine tool must have with process information. For example: feed speed, spindle speed, spindle rotation, tool change, coolant switch, etc. This information is stored in information carriers (such as magnetic disks, punched paper tapes, magnetic tapes, etc.). ) according to a certain format, and then read by the numerical control system on the machine tool (either directly through the keyboard of the numerical control system or through communication). Through decoding, the machine tool can move and process parts. Modern CNC machine tool is a typical product of mechatronics, and it is the technical basis of a new generation of production technology and computer integrated manufacturing system.

The development trend of modern CNC machine tools is high speed, high precision, high reliability, multi-function, compound, intelligent and open structure. The main development trend is to develop an intelligent universal numerical control device with open hardware and software structure. Numerical control technology is the basis of machining automation and the core technology of numerical control machine tools. Its level is related to the strategic position of the country and the level reflecting the comprehensive strength of the country. It develops with the development of information technology, microelectronics technology, automation technology and detection technology. CNC machining center is a kind of CNC machine tool with tool magazine, which can automatically change tools and perform various machining operations on workpieces within a certain range. The characteristics of machining parts in machining center are as follows: after the machined parts are clamped once, the CNC system can control the machine tool to automatically select and replace tools according to different processes; Automatically change the auxiliary functions such as the spindle speed, feed speed and the movement track of the cutter relative to the workpiece, and continuously and automatically perform multi-process processing such as drilling, reaming, reaming, boring, tapping and milling on each processing surface of the workpiece. Because the machining center can automatically complete various processes in a centralized way, it can avoid human errors, reduce the time of workpiece clamping, measuring and machine tool adjustment, as well as the time of workpiece turnover, handling and storage, and greatly improve the machining efficiency and accuracy, so it has good economic benefits. Machining center can be divided into vertical machining center and horizontal machining center according to the position of spindle in space.

Many students want to learn CNC technology because they think it is a development direction. It seems that learning this is more promising and easier to find a job. So, what should we learn and where should we start? Means serve the purpose, because everyone has different learning purposes, so there must be more than one answer to the above questions. I can only speak in general terms.

1. Learn well in class. The knowledge in the college classroom is not necessarily the latest, but it must be the most systematic, and it is far from being old enough to die. Generally speaking, it is always the price of systematization of knowledge. If you go directly to the actual middle school without going through the classroom, you may learn the latest and most practical knowledge, but it will always be a part and you can't understand it as a whole. Therefore, the content in the college class must be learned well.

2. Get in touch with reality. There are fewer opportunities for college life to get in touch with reality. When I graduated, I had a production internship and was considered to be able to go to the production line. I was only allowed to have a look. This situation is estimated to be difficult to change. We can only try to make up for it from one side: we are good at learning book knowledge, so we should learn the book knowledge that is closest to reality.

3. What knowledge is the most practical book knowledge? Textbooks are difficult to write, new ones may, but many are not. The most practical book knowledge is actually the product introduction and instructions written for commercial interests, which is closest to reality. If you really work in numerical control technology after graduation, then these products are for you. Almost all you have to do is choose an application that suits you best. Choosing and making good use of these products, and developing these products by ourselves if possible, is almost all the work of people engaged in numerical control.

4. What products should be used for numerical control?

Answer: Controller (control card), motor, lead screw, guide rail, grating ruler (encoder) and PLC. That seems to be it. I'm here to list the products I think are the best or most commonly used, give their websites, and give ways to find information. If you have time and energy, go and see them. There is no end to learning, but you must find the right direction and see the most worthwhile information.

Controller: Siemens controller can be used for ordinary beds, such as 802S, 8 10D, 840D, etc. , and can download Chinese or English materials from Siemens website.

The control card can be used for special beds. The best seems to be PMAC, and the biggest seems to be Galile. PMAC data can be downloaded from the website of Yuanmaoxing Company, and galil data can be downloaded from the website of China Baolun Company. There seems to be some Chinese materials, but most of them are in English. You can also use the control card of Gogo company, which has the advantages of all Chinese materials (user manual, installation manual, programming manual, etc. ).

AC servo motors: expensive Siemens, cheap Panasonic, An Chuan. You can go to Siemens' website, which has Chinese information.

Lead screw guide rail: THK is the best, with Chinese information.

Grating encoder: Download product samples from Heidenham's website, with Chinese materials.

PLC: Siemens or Mitsubishi, it is recommended to download from Siemens website.