Advantages of machining

The machining accuracy of NC machine tools can generally reach 0. 0050.1 mm. CNC machine tools are controlled in the form of digital signals. Every time the NC device outputs a pulse signal, the moving parts of the machine tool move a pulse equivalent (generally 0.001mm). The average error between the reverse clearance and pitch of the machine tool feed transmission chain can be compensated by the NC device. Therefore, the positioning accuracy of NC machine tool is relatively high. 3. The machining quality is stable and reliable

Machining the same batch of parts, on the same machine tool, under the same machining conditions, using the same tool and machining program, the tool path is exactly the same, the parts are consistent and the quality is stable. 4) High productivity

CNC machine tools can effectively reduce the machining time and auxiliary time of parts. The range of spindle speed and feed speed of NC machine tool is large, which allows the machine tool to cut with large cutting capacity. CNC machine tools are now entering the era of high-speed machining. The rapid movement, positioning and high-speed cutting of moving parts of NC machine tools reduce the turnover time between processes of semi-finished products and improve the production efficiency. 5) Improve working conditions

Before machining, after the NC machine tool is adjusted, enter the program startup, and the machine tool can automatically and continuously machine until the machining is completed. Operators are mainly engaged in program input, editing, part loading and unloading, tool preparation, machining state observation, part inspection, etc. The labor intensity is greatly reduced, and the labor of machine tool operators tends to mental labor. In addition, machine tools are generally closed processing, which is clean and safe.

In the early stage of the development of CNC machine tools, the mechanical structure of CNC machine tools did not change much compared with general machine tools, but changed in automatic speed change, automatic indexing of tool holder and worktable, handle operation and so on. With the development of numerical control technology, considering its control mode and application characteristics, higher requirements are put forward for the productivity, machining accuracy and service life of machine tools. The main mechanisms of CNC machine tools have the following characteristics:

1. Due to the adoption of high-performance continuously variable spindle and servo drive system, the limit drive structure of NC machine tool is greatly simplified and the transmission chain is greatly shortened;

2. In order to adapt to continuous automatic machining and improve machining productivity, the mechanical structure of NC machine tool has high static and dynamic stiffness and damping accuracy, high wear resistance and small thermal deformation;

3. In order to reduce friction, eliminate transmission clearance and obtain higher machining accuracy, better transmission components are used, such as ball screw pair, rolling guide rail, clearance elimination gear transmission pair, etc.

4. In order to improve working conditions, reduce auxiliary time, improve operability and improve labor productivity, auxiliary devices such as automatic tool clamping device, tool magazine, automatic tool change device and automatic chip removal device are adopted.