Although CNC turning lathe has superior processing flexibility than ordinary lathes, there is still a certain gap with ordinary lathes in terms of the production efficiency of a certain part. Therefore, improving the efficiency of CNC lathes becomes the key. The rational use of programming skills and the preparation of high-efficiency machining programs often have unexpected effects on improving the efficiency of machine tools.
The CNC turning lathe has two axes, namely the spindle Z and the tool axis X. The center of the bar material is the origin of the coordinate system. When each knife approaches the bar material, the coordinate value decreases, which is called feed. On the contrary, if the coordinate value increases, it is called retraction.
When retracting to the tool start position, the tool stops, this position is called the reference point. The reference point is a very important concept in programming. After each automatic cycle is executed, the tool must return to this position to prepare for the next cycle. Therefore, before executing the program, the actual positions of the tool and the spindle must be adjusted to keep the coordinate values consistent.
However, the actual position of the reference point is not fixed. Programmers can adjust the position of the reference point according to the diameter of the part, the type and quantity of tools used, and shorten the idle travel of the tool, thereby improving efficiency.
There are a large number of short pin shaft parts in low-voltage electrical appliances, their length-diameter ratio is about 2~3, and the diameter is mostly below 3mm.
Due to the small geometric size of the parts, it is difficult for ordinary instrument lathes to be clamped and the quality cannot be guaranteed. Only one part is processed in each cycle if programmed according to the conventional method. But due to the short axial dimension, the machine tool spindle slider will reciprocate frequently in the guide rail part of the machine bed and the clamping mechanism of the spring chuck will move frequently.
After working for a long time, the above method will cause local excessive wear of the CNC turning lathe guide rail, affecting the machining accuracy of the machine tool, and even causing the machine tool to be scrapped. The frequent action of the clamping mechanism of the collet will cause damage to the control electrical appliance. To solve the above problems, it is necessary to increase the feeding length of the spindle and the action interval of the clamping mechanism of the collet chuck, and at the same time, the productivity cannot be reduced.
From this, it is envisaged that if several parts can be processed in one machining cycle, the feed length of the spindle is several times the length of a single part, and even the maximum running distance of the spindle can be reached. And the action time interval of the spring chuck clamping mechanism is correspondingly extended to several times of the original.
More importantly, the auxiliary time of the original single part is divided among several parts, and the auxiliary time of each part is greatly shortened, thereby improving the production efficiency.
In the CNC turning lathe, the movement of the tool is driven by the stepping motor. Although there is a quick point positioning command G00 in the program command, it is still inefficient compared with the feeding method of the ordinary lathe. Therefore, in order to improve the efficiency of the machine tool, the operating efficiency of the tool must be improved.
The idle travel of the tool refers to the distance that the tool travels when it approaches the workpiece and returns to the reference point after cutting. As long as the idle travel of the tool is reduced, the operating efficiency of the tool can be improved.
In terms of CNC turning lathe adjustment, the initial position of the tool should be arranged as close to the bar as possible.