To understand the impact of CNC system on CNC machine tools, we first need to know the structure of CNC system. The CNC system is mainly composed of human-computer interaction interface + CNC core + programmable logic controller + driver, and the human-computer interaction interface is used for human-computer interaction, and the core of the CNC is the core of the CNC system, which is used for trajectory calculation, position adjustment, and related control, such as acceleration, tool data, zero point offset, and the related control. A variety of complex machine tool functions. The programmable logic controller is used to control the logic of machine tools, such as knife library, hydraulic equipment and so on. The driver is the actuator, which adjusts the electric current loop and speed loop of the motor so that it can quickly and accurately complete the instructions issued by the core of the CNC. Numerical control system is not only a part of numerical control machine tool, but also a complete set of solutions, which includes two parts of hardware and software, only when the hardware and software are combined, and the human-computer interaction interface in the CNC system, the core of numerical control, the programmable logic controller, the driver Co operation, and the co completion of the machine. The control of bed can ensure the high accuracy and high quality of machine tools. Therefore, the quality of CNC system will directly affect the accuracy and efficiency of CNC machine tools. In general, the “good CNC system” defined by the public will configure high-end servo motors. A good CNC system can provide various types of motors for user selection, such as high dynamic motors, large inertia motors, etc. The user can choose the motor with different characteristics according to the different requirements of the machine tool. Good servo motors usually have higher encoder resolution. The larger the resolution, the smaller the speed fluctuation. The motor with high resolution encoder will be more stable and more precise. People in the industry know that there will be a lot of elastic connections between motor and machinery (such as elastic coupling). After a series of elastic links, the machine will have subtle errors in the transmission process, and the system at this time only knows the feedback of the motor and does not know the error in the transmission, so the actual control precision will be affected by this effect. In this case, the middle and high end CNC system can access the grating ruler as a direct measurement system to form a “full closed loop”, so that the system can directly control and adjust the mechanical feedback through the grating ruler to improve the precision of the machine tool. Nowadays, many high-end CNC systems have been able to achieve more than nanometer accuracy. This also means that the high-end CNC system can provide higher control accuracy and achieve a better interpolation trajectory. Not only that, the vibration of the machine tool in the process of production is unavoidable to be disturbed by the external environment, such as cooling equipment, hydraulic equipment, or other machine tools. This kind of problem can be found by measuring the position deviation of the grating ruler to find these disturbances, but it is difficult to suppress and eliminate the dynamic response parameters of the machine tool. Advanced positioning control functions like the same way to suppress external interference, thereby further improving machine tool processing performance.
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