CNC machine tool features new technologyUpdate date：2019/12/19

Advances in the world of CNC machine tools NC system technology features new technology for CNC machine tools technical progress provided the conditions. To meet the needs of the market, achieve higher requirements of modern manufacturing technology CNC technology proposed by the current world development numerical control technology and equipment are mainly reflected in the following aspects of the technical characteristics:

1. High-speed, high efficiency

The speed of the machine direction, not only can greatly improve the processing efficiency and reduce processing costs, but also improve the surface quality and precision machining parts. Ultra-high-speed processing technology for manufacturing efficient, high-quality, low-cost production has broad applicability. Since the 1990s, European, American and Japanese countries are scrambling to develop a new generation of high-speed CNC machine tool application, accelerate the pace of development of high-speed machines. High-speed spindle units (spindle, speed 15000-100000r / min), high-speed and high feed motion member acceleration / deceleration (rapid traverse 60 ~ 120m / min, cutting feed rate of up to 60m / min), high-performance CNC and servo systems and CNC tool system appeared a new breakthrough, reached a new level of technology. With ultra-high-speed cutting mechanism, hard wear long tool life and abrasive materials, high-power high-speed spindle, high acceleration / deceleration linear motor drive feed components and high-performance control system (including monitoring systems) and guards and a series of art to address key technology for the development and application of a new generation of high-speed CNC machine tools to provide a technical basis. At present, ultra high-speed machining, turning and milling cutting speed has reached 5000 ~ 8000m / min or more; spindle speed of 30,000 rev / min (some up to 100 000 r / min) or more; moving speed table (into speed): In a resolution of 1 micron, at 100m / min (some to 200m / min) or more, at a resolution of 0.1 microns, at 24m / min or more; automatic tool change speed in less than one second; small line interpolation feed speed up to 12m / min.

2. High Precision

Developed from precision machining to ultra-precision machining, it is the direction of the world's industrial powers committed to development. Its precision from submicron to micron level, and even nanoscale (<10nm), the increasingly wide range of applications. Currently, in the high-precision machining requirements, the general level of CNC machining accuracy has been increased to ± 10μm ± 5μm; precision machining precision machining centers from ± 3 ~ 5μm, up to ± 1 ~ 1.5μm, even higher; ultra-precision machining precision into the nanometer (0.001 micron), spindle rotation accuracy of 0.01 to 0.05 micron, 0.1 micron processing roundness, surface roughness Ra = 0.003 micron and so on. These machines are generally used vector control variable frequency drive motor spindle (spindle motor integration), less than 2 Xie spindle runout, axial runout less than 1 Xie, shaft imbalance reaches G0.4 level. High precision machine tools, high-speed feed drives, there are "high-speed precision rotary servo motor Ball" and "direct drive linear motor" types. In addition, new parallel machine is also easy to achieve high-speed feed. Ball screw technology is mature, widely used, not only to achieve higher accuracy (ISO3408 1 level), and cost to achieve high speed is relatively low, so far is still used in many high-speed machine tools. The current use of high-speed machine tools ball screw drive maximum speed 90m / min, acceleration of 1.5g. Ball is a mechanical transmission, the inevitable presence of elastic deformation, friction and backlash in the transmission process, resulting in a corresponding movement of hysteresis and other non-linear error, in order to exclude the impact of these errors on machining precision machine tools started in 1993 Application of direct drive linear motor, because it is not in the middle part of the "zero transmission", only a small movement inertia, system rigidity, fast response, can achieve high speed and acceleration, and its stroke length theoretically unlimited, positioning accuracy under the influence of high-precision position feedback system is also easy to achieve high levels of high-speed high precision machine tools in particular, a large machine ideal drive. Currently used high-speed linear motor finishing machine has reached the maximum rapid traverse speed 208 m / min, acceleration of 2g, and there is room for development.

3. High reliability

With the development of network applications, CNC machine tools, high reliability of CNC machine tools has become numerical control system manufacturers and CNC machine tool manufacturers goal. Work two shifts a day for no factory, if the requirements of continuous work within 16 hours, no failure rate in P (t) = more than 99%, the average CNC machine uptime MTBF must be greater than 3000 hours . We are only one CNC machine tools, the failure rate as the ratio of the host and the NC system is 10: 1 (host NC reliable than an order of magnitude). CNC system is necessary at this time MTBF more than 33,333.3 hours, and one of the numerical control device, spindle and drive etc. MTBF must be greater than 100,000 hours. The current value of MTBF foreign numerical control device has reached more than 6,000 hours, the drive for more than 30,000 hours, but you can see from the ideal target is still lagging behind.

4, composite

There are a lot of useless time-consuming in the workpiece handling, loading and unloading, installation and adjustment, tool change and spindle liter in parts processing, the deceleration, in order to minimize the dead time, people want to integrate different processing functions at the same On one machine, so the machine complex functions developed rapidly in recent years become models. Flexible manufacturing composite processing machine category concept refers to a workpiece clamping, NC machine tools will be able to follow procedures, automatic multi-step process for the processing of the same class or different classes of process methods in order to complete a major or even complex shapes All vehicles, milling, drilling, boring, grinding, tapping, reaming and reaming and other processing steps. Parts on the prism, the machining center is the most typical was the same kind of multi-step process for composite processing machine. Facts have proved that the machine complex processing can improve the precision and efficiency, saving floor space in particular parts of the processing cycle can be shortened.

5, multiaxial

With the popularity of 5-axis CNC system and programming software, 5-axis controlled machining centers and CNC milling machine has become a development hot spot, due to the processing of free-form surface, 5-axis control of the ball-cutter NC programming relatively simple, and can make the ball end mill during the milling process of three-dimensional surfaces remain reasonable shear, thereby significantly improving the machined surface roughness and greatly improve processing efficiency, and joint control of the machine in 3 axes can not Avoid cutting speed close to the ball-cutter cutting the ends of the participating zero, so the 5-axis machine with its irreplaceable performance advantage has become the focus of major machine tool manufacturers to actively develop and compete. Recently, foreign 6-axis control is also studying the use of non-rotating tool machining center, although it is not limited machining shape and depth of cut may be thin, but the processing efficiency is too low a difficult practical fashion.

6, intelligent

Intelligence is a general direction of development of manufacturing technology of the 21st century. Intelligent processing is d on neural network control, fuzzy control, digital network technology and processing theory, it is necessary to simulate human intelligence activities of experts in the process to resolve the many uncertainties of the process, to be made by human intervention problem. Intelligent content included in all aspects of numerical control system: the pursuit of processing efficiency and quality of intelligence, such as adaptive control, automatic generation of process parameters; to improve intelligence-driven performance and easy to use to connect, such as feedforward control Adaptive computing motor parameters, automatic identification load select models, self-tuning, etc; simplify programming, simplifying the intelligence operations, such as intelligent automatic programming, intelligent man-machine interface; intelligent diagnosis, intelligent monitoring, easy diagnosis and maintenance systems and so on. Many studies are ongoing in the world of intelligent cutting system in which intelligent numerical control apparatus Research Japan representative for the drilling of intelligent processing program.

7, network

CNC machine network, mainly refers to the machine tool, network connections and other control systems via numerical control system equipped with external or host computer. CNC machine tools generally the first site for the production and internal LAN, then leads outside the enterprise via the Internet, which is called Internet / Intranet technology. With the maturity and development of network technology, the industry has recently proposed the concept of digital manufacturing. Digital manufacturing, also known as "e- Manufacturing," is one of the hallmarks of modern machinery manufacturing enterprises, the international manufacturer of advanced machine tools available in today's standard configuration mode. With the extensive use of information technology, more and more domestic users in the imported CNC machine tools require telecommunication services and other functions. Machinery manufacturing enterprises on the basis of commonly used CAD / CAM, d on the increasingly widespread use of CNC machining equipment. NC application software increasingly rich and have "humane." Virtual design, virtual manufacturing, and other high-end technology is also increasingly being sought for engineering and technical personnel. Replace complex hardware by software intelligence, it is becoming an important trend in the development of modern machine tools. In the target digital manufacturing through process reengineering and information technology transformation, ERP and other advanced business management software has emerged for companies to create higher economic returns.

8, flexible

Trend of CNC machine tools to the flexible automation system development: from the point (NC single, machining centers and CNC machine tool), line (FMC, FMS, FTL, FML) to face (Section workshop independent manufacturing Island, FA), body ( CIMS, distributed network integrated manufacturing system) direction, on the other hand to focus on the application and economic direction. Flexible manufacturing automation technology is the primary means to adapt to the dynamic market demand and rapid product updates, is the main trend of countries manufacturing industry is the basis of advanced technology and manufacturing. The focus is to improve system reliability, practical into the premise for easy networking and integration as the goal; focus on strengthening pioneering cell technology, perfect; CNC single development to high-precision, high speed and high flexibility direction; CNC machine tools and constitute flexible manufacturing system can be easily and CAD, CAM, CAPP, MTS to information integration direction; network system to an open, integrated and intelligent direction.

9, Green

l cutting machine tools in the 21st century must be environmentally friendly and energy in an important position, that is, to achieve a green cutting process. Currently this green process focused not on the use of cutting fluids, mainly because cutting fluid only pollute the environment and harm the health of workers, and increase the consumption of resources and energy. Dry cutting is generally carried out in the atmosphere, but also included in the special gas atmosphere (nitrogen, cold or dry electrostatic cooling technology) without the use of cutting the cutting fluid. However, for some combination of machining and the workpiece, does not use cutting fluid and dry cutting is hard to practical application, it has emerged using extremely minimal quantity lubrication (MQL) quasi-dry cutting. Currently in Europe, large quantities of machining, 10 to 15 percent of processing used dry and quasi-dry cutting. For for a variety of processing methods / workpiece combination of machining centers and the like machine tools, mainly using quasi-dry cutting is usually very small amount of the mixture of cutting oil and compressed air is ejected through the hollow channel within the spindle and tools cutting area. In all kinds of l-cutting machine tools, cutting is the most dry hobbing. In short, the progress and development of CNC technology for the development of modern manufacturing industry provides a good condition, the manufacturing industry towards efficiency, quality and user-friendly direction. Can be expected, with the extensive application and development of CNC machine tools and CNC machine tool technology, the manufacturing industry will usher in a traditional manufacturing model enough to shake the profound revolution.