As a high-precision machine tool, the CNC machining center, due to improper operation or programming errors, is easy to make the tool or tool holder hit the workpiece or machine tool. The light one will damage the tool and the processed parts, and the heavy one will damage the machine tool components, lose the machining accuracy of the machine tool, and even cause personal accidents. Therefore, anti-collision is very necessary. In the use of a CNC machining center, it is absolutely not allowed for the tool to collide with the machine tool or workpiece. The following causes of collision knife can be summarized into 9 reasons:

1. Programming error

The process arrangement is wrong, the process undertaking relationship is not considered in detail, and the parameter setting is wrong.

Example:

• The coordinate is set to zero at the bottom, but in practice, it is set to zero at the top;

• The safety height is too low, resulting in the tool can not be completely lifted out of the workpiece;

• The secondary cutting allowance is less than that of the previous knife;

• After the program is written, the path of the program should be analyzed and checked;

2. Program sheet remarks error

For example:

• The number of one-sided collisions is written in the middle of four sides;

• The clamping distance of the vise or the protruding distance of the workpiece are marked incorrectly;

• If the remarks of the tool extension length are not clear or incorrect, the tool will collide;

• The procedure sheet should be as detailed as possible;

• When the program sheet is changed, the principle of replacing the old with the new should be adopted: the old program sheet should be destroyed.

3. Tool measurement error

For example:

• The tool setting data input does not consider the tool setting bar;

• The tool loading is too short;

• Scientific methods should be used for tool measurement, and more accurate instruments should be used as far as possible;

• The length of the knife should be 2-5mm longer than the actual depth.

4. Program transfer error

The program number calls incorrectly or the program is modified, but the old program is still used for processing;

The on-site processor must check the detailed data of the program before processing;

For example, the time and date of programming are simulated by the bear clan.

5. Knife selection error

6. The blank exceeds the expectation, and the blank is too large, which is inconsistent with the blank set in the program

7. The workpiece material itself has defects or the hardness is too high

8. Clamping factors, and cushion block interference and not considered in the procedure

9. Machine tool failure, sudden power failure, knife collision caused by lightning, etc