The tool holder is overshooting or not turning into position

1. The tool holder is overshooting. The mechanical cause of this fault is more likely, mainly because the backrest device does not work.

* First check whether the backrest positioning pin is flexible and whether the spring is fatigued. At this time, the positioning pin should be repaired to make it flexible or replace the spring.

* Secondly, check whether the backrest ratchet and worm are disconnected. If disconnected, the connecting pin needs to be replaced.

* If overshoot still occurs, it may be because the tool is too long and too heavy, and the positioning pin spring with a slightly larger elastic modulus should be replaced.

2. The tool holder is not in place (sometimes it stops suddenly in the middle).

This fault is mainly caused by the misalignment of the signal plate contact and the elastic sheet contact, that is, the fixed offset of the tool position signal bakelite plate.

* First readjust the position of the signal plate and the elastic sheet contact and fix them firmly.

* If the fault still cannot be eliminated, it may be that the signal plate clamping nut is loose, causing the position to move.