CBM-710/720 Service Manual
2.Mechanism and Principle of Operation
1)Outline of Mechanism
The AC-2 and AC-3 are designed as the DP-505 and DP-600 small dot printers and characterized by compact and lightweight types. The mechanism of this unit consists of 4 blocks; frame, power transmission mechanism, detector, and movable blade mechanism.
2)Mechanism and Principle of Operation
2)-1 Power transmission mechanism
Cutter Gear
Worm
Motor Gear
Fig. 1
The reduction gear train of this auto cutter is composed of the motor gear mounted onto the motor shaft, worn, and two cutter gears. One rotation of the motor gear rotates the cutter gear by 7/520 (
1/74) (See. Fig. 1.)
2)-2 Detector
The detector is composed of the mechanism contract switch and cutter gear cam.
This detector detects the home position of the movable blade for partial cut (see Fig. 2), turn-around position (see Fig. 3) and returned blade. It is turned on when the blade is at the home position and turned off when the blade returns. The position where the detector is turned off from on after starting of the movable blade is the turn-around position for partial cut.