VORRICHTUNG ZUM ÜBERWACHEN DER GEWINDEBOHROPERATION.

摘要

The female threading operation is carried out by driving a tap (14) using a built-in main shaft motor (12) which directly drives the tap (14) without using transmission mechanism and using another motor (22) moves the tap together with the main shaft motor (12) in the lengthwise direction (Z) of the tap. The two motors are controlled for their rotation in synchronism with each other, and a difference operation unit (32) always monitors the difference between an instructed speed of revolution sent from a synchronism control unit (36) to the built-in main shaft motor (12) and a practical speed of revolution of the built-in main shaft motor detected by a revolution detector (16). When the difference becomes greater than a predetermined value a light emitting diode (40) or the like produces an alarm.