| 摘要 |
PURPOSE:To simplify and speed up preparatory works by electrically controlling the axial moving speed of a tap. CONSTITUTION:A required tap 4 is fixed to a chuck 3 and a pitch corresponding to the tap 4 is applied by a key 15 as an input control data. An induction motor 6 is started to rotate a spindle 2 with a constant speed. Next, a pulse motor 11 is rotatd by a pulse motor drive circuit 14c to start the tapping operation. Then, oscillating frequency of a pulse generating circuit 14a is controlled by control data applied to the input of a oscillating frequency control circuit 14b by CPU to rotate the pulse motor 11 with rotational frequency corresponding to the pitch of the tap 4. Turning force of the pulse motor 11 is transmitted to a rack of a quill 1 through a pinion 13 and intermediate gear 10 to move axially the quill 1. |
