What is the development trend of CNC machine tools? CNC machine tool is an abbreviation for digital control machine tool, which is an automated machine tool equipped with a program control system. This control system can logically process programs with control codes or other symbolic instructions, decode them, represent them with coded numbers, and input them into the CNC device through information carriers. After calculation and processing, various control signals are sent out by the CNC device to control the action of the machine tool, and the parts are automatically processed according to the shape and size required by the drawings.
CNC machine tools have effectively solved the problem of complex, precise, small batch, and multi variety parts processing. They are a flexible and efficient automated machine tool, representing the development direction of modern machine tool control technology and a typical electromechanical integration product.
Development Trend of CNC Machine Tool Industry
1. High speed.
With the rapid development of industries such as automobiles, national defense, aviation, and aerospace, as well as the application of new materials such as aluminum alloys, the demand for high-speed machining of CNC machine tools is becoming increasingly high.
(1) Spindle speed: The machine tool adopts an electric spindle (built-in spindle motor), with a maximum spindle speed of 200000 r/min;
(2) Feed rate: at a resolution of 0.01 μ At m, the maximum feed rate reaches 240m/min and precise machining of complex surfaces can be achieved;
(3) Computing speed: The rapid development of microprocessors has provided a guarantee for the development of CNC systems towards high speed and precision. We have developed CNC systems with CPUs that have grown to 32-bit and 64-bit, and frequencies that have increased to hundreds or even thousands of megahertz. Due to the significant improvement in computational speed, when the resolution is 0.1 μ m. 0.01 μ At m, a feed speed of up to 24-240m/min can still be achieved;
(4) Tool exchange speed: Currently, the tool exchange time of advanced machining centers abroad is generally around 1 second, with the highest reaching 0.5 seconds. Chiron, a German company, designed the tool magazine in a basket style, with the spindle as the axis and the tools arranged around the circumference. Its tool to tool change time is only 0.9 seconds.
2. High precision.
The requirements for the accuracy of CNC machine tools are no longer limited to static geometric accuracy. The motion accuracy, thermal deformation, and vibration monitoring and compensation of machine tools are receiving increasing attention.
(1) Improving the control accuracy of CNC system: Adopting high-speed interpolation technology to achieve continuous feeding with small program segments, refining the CNC control unit, and using high-resolution position detection devices to improve position detection accuracy (Japan has developed an AC servo motor with an embedded position detector of 106 pulses/revolution, which can achieve a position detection accuracy of 0.01) μ M/pulse), the position servo system adopts methods such as feedforward control and nonlinear control;
(2) Adopting error compensation technology: adopting technologies such as reverse clearance compensation, screw pitch error compensation, and tool error compensation to comprehensively compensate for the thermal deformation error and spatial error of the equipment. The research results indicate that the application of comprehensive error compensation technology can reduce machining errors by 60% to 80%;
(3) Adopting grid inspection and improving the motion trajectory accuracy of the machining center, and predicting the machining accuracy of the machine tool through simulation to ensure accurate positioning of the machine tool
