The linear servo system adopts a direct drive method. Compared with the traditional rotary transmission method, the biggest feature is that all the mechanical intermediate transmission links between the motor and the worktable are eliminated, that is, the machine tool is fed to the transmission chain. The length is shortened to zero.
This “zero transmission” method brings performance indicators that cannot be achieved by the rotary drive method. For example, the acceleration can reach more than 3G, which is 10-20 times that of the traditional drive device, and the feed speed is 4 to 5 times that of the traditional device. In terms of the working principle of the motor, linear motors have DC, AC, stepping, permanent magnet, electromagnetic, synchronous and asynchronous, etc.; and in terms of structure, there are moving coil type, moving iron type, flat type and Cylindrical and other forms. Outline drawing of the linear servo system. There are mainly high-precision, high-frequency response, small-stroke linear motors and large-stroke, long-stroke, high-precision linear electric motors that are applied to CNC machine tools.
Linear servo is an ideal drive mode for high-speed and high-precision CNC machine tools, which has attracted the attention of machine tool manufacturers, and technology has developed rapidly. At the European Machine Tool Show in 2001, dozens of companies exhibited high-speed machining tools driven by linear electric ideas, with a rapid traverse speed of 100~120m/min, an acceleration of 500m/min, and an acceleration of 6g. All of these indicate that the second-generation high-speed machine-booking represented by linear motor drive will replace the first-generation high-speed machine-booking represented by high-speed ball screw drive, and it will occupy a dominant position in use.