Non-standard machine tools belong to the range of precision CNC machine tools, which can not only meet the high efficiency and automation of machine tools, but also meet the requirements of mechanical high precision, and improve the use efficiency of non-standard machine tools.
Therefore, from the structural point of view, non-standard machine tools have five major characteristics, which are described in detail as follows.
- Between the movement of the working parts of the non-standard machine tool, a “soft” connection is established through an electronic computer, which replaces the “hard” connection of the traditional mechanical transmission chain, so the driving mechanism of each moving part of the machine tool is independent. This "soft" connection has the advantages of fast movement speed, small transmission gap, convenient control, simple structure and small movement inertia.
- The feed drive components adopt many new drive components such as power stepper motors, electro-hydraulic pulse motors, servo motors, etc. The drive system, especially the last link of the transmission, has a high transmission rigidity, and its structure usually adopts a preloaded precision ball screw nut pair.
- The transmission chain has taken measures to eliminate backlash and added necessary backlash compensation links.
- The feed speed range is much wider than that of ordinary machine tools. On the one hand, in order to improve efficiency and shorten the time of rapid advancing (many CNC machine tools have increased the rapid traverse speed to more than 15 m/min), on the other hand, to meet the requirements of powerful cutting and precise positioning (some machine tools have achieved a ratio of 30,000 Ultra-low speed feed with one speed ratio).
- Choose guide parts with low friction coefficient and high wear resistance, such as rolling guides, static pressure guides, hardened steel guides, etc., or adopt mechanical, pneumatic, or hydraulic unloading measures. In the case of a large stroke, a circulating rolling guide body is used to eliminate crawling and improve the dynamic response (DVnmmic response) capability.
