| 摘要 |
PURPOSE:To enable a rotary blade of a rotary cutter to be rested securely on a predetermined position by rotating with low speed a DC motor repeating the drive and braking when the rotary blade reaches the neighborhood of the stationary position. CONSTITUTION:An early drive means 21 for a motor generates a drive pulse 22 having a predetermined width just before a blank is cut to rotate continuously a DC motor 7D for a time corresponding to the pulse width. When a rotational position detector 24 detects the release of a blade from the stationary position, a detecting signal 25 is supplied to a logic circuit 26 to thereafter alternately operate a power supply circuit 23 and a brake circuit 28 and drive the DC motor 7D with low speed. Thus, when the rotary blade 7B rotates one revolution to return to the stationary position, a position detecting circuit 24 detects that return to interrupt the power supply to the DC motor 7D. |
