At present, the world's advanced manufacturing technology continues to rise, the application of ultra-high-speed cutting, ultra-precision machining and other technologies, the rapid development of flexible manufacturing systems and the continuous maturity of computer integrated systems have put forward higher requirements for CNC machining technology. CNC machine tools are important basic equipment in the machine tool manufacturing industry, so its development has always attracted people's attention. In recent years, my country's machine tool manufacturing industry has faced both good opportunities for the development of manufacturing equipment and the pressure of market competition. From a technical point of view, accelerating the promotion of numerical control technology will be a key to the sustainable development of the machine tool manufacturing industry. Today's CNC machine tools are developing in the following directions.

1. Maximize reliability

The reliability of CNC machine tools has always been the main indicator that users care about. The numerical control system will use higher integrated circuit chips and use large-scale or ultra-large-scale special-purpose and hybrid integrated circuits to reduce the number of components and improve reliability. The hardware functions are softwareized to meet the requirements of various control functions, and the modularization, standardization, generalization and serialization of the hardware structure of the machine tool body are adopted, which not only increases the hardware production batch, but also facilitates the organization of production and quality control. It also realizes fault diagnosis and alarm for the hardware, software and various external devices in the system by automatically running various diagnostic programs such as startup diagnosis, online diagnosis and offline diagnosis. Use alarm prompts to eliminate faults in time; use fault-tolerant technology to adopt "redundant" design for important components to achieve fault self-recovery; use various testing and monitoring technologies In the event of an accident, the corresponding protection is automatically carried out.

2. Miniaturization of control system

The miniaturization of the numerical control system facilitates the integration of mechanical and electrical devices. At present, ultra-large-scale integrated components and multi-layer printed circuit boards are mainly used, and three-dimensional installation methods are adopted to enable high-density installation of electronic components and reduce the occupied space of the system on a large scale. The use of a new type of color liquid crystal thin display to replace the traditional cathode ray tube will further miniaturize the numerical control operating system. In this way, it can be conveniently installed on the machine tool, which is more convenient for the operation and use of the CNC machine tool.

3. Intelligent

Modern CNC machine tools will introduce adaptive control technology to automatically adjust working parameters according to changes in cutting conditions, so that good working conditions can be maintained during the machining process, so as to obtain higher machining accuracy and smaller surface roughness. Tool life and equipment productivity. It has the functions of self-diagnosis and self-repair. During the whole working state, the system can carry out self-diagnosis and inspection of the CNC system itself and various equipment connected to it at any time. Once a fault occurs, measures such as shutdown are immediately taken, and a fault alarm is performed to indicate the location and cause of the fault. It can also automatically take the faulty module offline and switch on the spare module to ensure the requirements of an unmanned working environment. In order to achieve higher fault diagnosis requirements, the development trend is to use artificial intelligence expert diagnosis system.

4. CNC programming automation

At present, CAD/CAM graphic interactive automatic programming has been widely used, which is a new trend in the development of numerical control technology. It uses the part processing pattern drawn by CAD, and then performs calculation and post-processing through the tool path data in the computer, so as to automatically generate the NC part processing program to realize the integration of CAD and CAM. With the development of CIMS technology, the fully automatic programming method of CAD/CAPP/CAM integration has appeared. The biggest difference between it and CAD/CAM system programming is that the processing parameters required for programming do not need to be manually involved, but directly from the Obtained from the CAPP database in the system.

5. High speed and high precision

Speed and precision are two important indicators of CNC machine tools, which are directly related to processing efficiency and product quality. At present, the numerical control system adopts a processor with a higher number of digits and a higher frequency to improve the basic operation speed of the system. At the same time, a super-large-scale integrated circuit and a multi-microprocessor structure are used to improve the data processing capability of the system, that is, to improve the speed and precision of interpolation operations. And the linear servo feeding mode of the linear motor directly driving the machine tool table is adopted, and its high speed and dynamic response characteristics are quite superior. The use of feedforward control technology greatly reduces the tracking lag error, thereby improving the machining accuracy of corner cutting.

6. Multifunctional

All kinds of machining centers equipped with automatic tool changing mechanism (tool magazine capacity can reach more than 100) can simultaneously realize milling, boring, drilling, turning, reaming, reaming, tapping, etc. on the same machine tool. Multi-spindle and polyhedron cutting are also used in modern CNC machine tools, that is, different parts of a part are cut in different ways at the same time. Due to the multi-CPU structure and hierarchical interrupt control method adopted in the numerical control system, parts processing and programming can be performed on one machine tool at the same time, realizing the so-called "processing in the foreground and editing in the background". In order to meet the requirements of flexible manufacturing systems and computer integration systems, the CNC system has a long-distance serial interface, and can even be networked to realize data communication between CNC machine tools, and can also directly control multiple CNC machine tools.

In order to meet the requirements of ultra-high-speed machining, the CNC machine tool adopts the structure of the spindle motor and the machine tool spindle, which realizes the integration of the frequency conversion motor and the machine tool spindle. The bearing of the spindle motor adopts magnetic bearing, hydrodynamic and static pressure bearing or ceramic rolling bearing. form.

CNC machine tools have attracted worldwide attention with its excellent flexible automation performance, excellent and stable precision, agile and diversified functions, and it has created a precedent for the development of mechanical products to mechatronics, so CNC technology has become an important part of advanced manufacturing technology. a core technology. On the other hand, through continuous research, the deepening application of information technology has promoted the further improvement of CNC machine tools.