The mechanical causes of dimensional instability in CNC lathe processing are analyzed as follows:
1. The connection between the servo motor shaft and the lead screw is loose, causing the lead screw and the motor to be out of sync, resulting in dimensional errors.
Detection only need to make a mark on the coupling of the servo motor and the lead screw, and move the worktable (or tool holder) back and forth with a faster magnification. Due to the inertia of the worktable (or turret), the coupling will appear obvious relative movement at both ends. This kind of fault is usually manifested in the processing size only to change in one direction, only the coupling screw can be evenly tightened to eliminate.
2. Poor lubrication between the ball screw and the nut increases the movement resistance of the worktable (or tool holder), and the movement command cannot be executed completely and accurately.
This kind of fault is usually manifested in the size of the parts in the scope of a few wires without regular changes, only the lubrication can be improved to eliminate the fault.
3, CNC lathe table (or tool holder) movement resistance is too large, generally for the strip adjustment is too tight, machine tool guide surface lubrication caused by poor.
The fault phenomenon is generally manifested in the size of the parts in the range of a few wires without rules. The inspection can be carried out by observing the size and change of the position deviation, usually with a large difference when the forward and reverse directions are stationary. This kind of failure only needs to readjust the strip and improve the lubrication of the guide rail.
4, rolling bearing wear or improper adjustment, resulting in excessive movement resistance.
This failure phenomenon is also usually manifested by irregular changes in size within a few filaments. The inspection can be carried out by the position deviation, and the method is the same as above. This kind of fault only needs to replace the worn bearing and carefully adjust, the fault can be eliminated.
5, the screw gap or gap compensation amount is improper, by adjusting the gap or changing the gap compensation value can eliminate the fault.