How to solve the problem of tool loss in automatic lathe machining?

At present, the automatic tool changing device (ATC) of automatic lathe machining center has two common types of tool changing methods, one is that the tool is directly exchanged by the spindle from the tool library, and the other is to rely on the manipulator to complete the exchange of the spindle and the tool library. The first tool change method is suitable for small machining centers, the tool library is small, the tool is less, the tool change action is simple, and the fault such as the knife is easy to find and can be eliminated in time. The second way of changing the knife belongs to a more complex one in terms of structure and action. Below, Xiaobian to introduce the first way to change the knife out of the solution:

1. Dynamic lathe processing to check the manipulator to perform ATC tool change troubleshooting steps, stop the manipulator in the vertical limit position. Check the two grippers on the arm of the manipulator and the spring supporting the gripper and other accessories. No problem was found, indicating that the clamping tool of the manipulator is tight, and the tool will not fall off when the manipulator is rotating.

2. Check the tool changing program For this fault only occurs in the process of tool changing and has nothing to do with other actions, edit an automatic tool changing program and execute it repeatedly, and run this program in order to find the real reason for the knife dropping. Edit the automatic tool change program as follows: O0200→S500→M03→G04X3.0→M06→M99→%.

3. During the operation of the program, the following situation is found: the spindle tool clamping is not in place, and even there is no clamping action, the manipulator rotates, and the tool is dropped. According to the previous tool change sequence analysis of spindle tool clamping in place stroke switch wrong action caused by tool failure. Open the PLC ladder diagram, monitor the travel switch (input is X2.5), press the travel switch repeatedly, and find that X2.5 is in the "0" state twice out of more than 20 times of pressing, and X2.5 cannot be transferred from the "1" state to the "0" phenomenon twice after pressing, according to the above determination that the travel switch is damaged. This switch is OMRONZC-Q2255, replaced with domestic CXW5-11Q1, the test is normal. A week later, the operator still reflected that there was a knife drop phenomenon, of course, the frequency of occurrence is small, which indicates that the knife failure has not been completely eliminated.

4. Check the clamping situation of the tool According to the phenomenon analysis of the tool with the spindle mounted out of position, it may be that the disc spring in the inner hole of the spindle can not clamp and tighten the tool, resulting in the tool installation is not in place, and even the tool is not installed and the tool is dropped. Disassembling the interior of the spindle, it was found that several pairs of disc springs had broken. So all the disc springs were replaced. There were no problems during the test run. After one shift, the knife dropped again.

5. Troubleshoot the fault repeatedly for two hours, automatic tool change hundreds of times. Finally found a fault: in the case that the manipulator is not in place, the tool on the spindle is loosened, the manipulator does not grasp the knife, and the knife is dropped, which indicates that the magnetic induction switch is in place.