CNC machine tool maintenance technology detailed

With the development of electronic technology and automation technology, the application of numerical control technology is more and more extensive. Based on microprocessors, CNC equipment marked by large-scale integrated circuits has been mass-produced, introduced and promoted in China. They have created conditions for the development of machinery manufacturing industry and brought great benefits. But at the same time, due to their advanced nature, complexity and high intelligence, there has been a leap in maintenance theory, technology and means.

CNC maintenance technology is not only a prerequisite for ensuring normal operation, but also plays a huge role in promoting the development and improvement of numerical control technology. Therefore, it has become a specialized discipline.

In addition, any CNC device is a process control device, which requires it to work flawlessly at every moment of real-time control. Any part of the fault and failure will cause the machine to stop, causing production to stop. Therefore, it is very necessary to repair the CNC system with such a complicated and precise structure. Especially for the introduction of CNC machine tools, most of them cost hundreds of thousands to tens of millions of dollars. In many industries, these devices are in critical positions, and if they fail to repair and troubleshoot in the event of a failure, they will cause significant economic losses.

There is still a big gap between our existing maintenance status and level and the level of design and manufacturing technology of imported equipment. The reasons for the gap are: poor quality of personnel, lack of digital testing and analysis methods, test analysis techniques for digital domain and digital domain and frequency domain synthesis, etc.

Below we start with the basic composition of modern CNC system, and explore the diagnosis and maintenance of CNC system.

The composition and characteristics of the CNC system:

At present, there are many kinds of numerical control systems in the world, each with different forms, and their respective structures have their own characteristics. These structural features are derived from the basic requirements of the initial design of the system and the ideas of engineering design. For example, there are very different requirements for point control systems and continuous trajectory control systems. For the T system and the M system, there is also a big difference. The former is suitable for the processing of parts of the rotary body, and the latter is suitable for the machining of parts of the irregular non-rotating body. For different manufacturers, based on historical development factors and the influence of different factors that vary from place to place, the design ideas may also have their own advantages. For example, the Dynapath system in the United States uses a small plate structure to facilitate board replacement and flexible integration, while the Japanese FANUC system tends to a large plate structure, which is beneficial to the reliability of the system work, and the average failure-free rate of the system is continuously improved. However, no matter which system, their basic principles and composition are very similar. Generally, the entire CNC system consists of three major components, namely the control system, the servo system and the position measurement system. The control system performs interpolation calculation according to the machining part program, and sends a control command to the servo drive system; the servo drive system amplifies the control command, and the servo motor drives the machine to move as required; the measurement system detects the movement position or speed of the machine, and feeds back to the control System to correct control commands. These three parts are organically combined to form a complete closed-loop controlled CNC system.