Paper End Detection Mechanism; Rear Cover Open Detection Mechanism; Auto Cutter Home Position Detection Mechanism - Samsung SRP-275 Service Manual

8-3-3 Paper end detection mechanism

The Switch-paper end consists of the paper end detection lever and micro switch, and is located on the
center of the Frame basket. This switch detects the presence/absence state of the paper roll.
The tip of the paper end detection lever is always pressed against the paper roll by a spring inside the micro
switch. Therefore, when there is a paper remaining on the roll, the paper end detection lever is pressed
against the paper roll as figure.
This keeps the micro switch turned on. When the almost out of paper on the roll the tip of the paper end
detection lever no longer presses against the paper roll and moves in the direction indicated by the arrow B.
This turns the micro switch off and generates a signal indicating that the paper roll is end.

8-3-4 Rear cover open detection mechanism

The Switch-cover rear open detects the Cover rear open/close state, the Switch-cover rear open is
located on the right of Cover middle.
This keeps the micro switch turned on. When the almost out of Cover rear the tip of the rear cover detection
lever no longer presses against the Cover rear and moves in the direction indicated by the arrow C.
This turns the micro switch off and generates a signal indicating that the Cover rear is open.

8-3-5 Auto cutter home position detection mechanism

The Auto cutter home position detection mechanism is located at the right end of the circular cutter subset
stroke. This mechanism confirms the position of the circular cutter and detects any abnormalities in its
operation. Initial setting is performed by sensing the detection plate on the rear of the AC upper cutter ass'y.
The Auto cutter home position sensor consists of an LED and a photo IC. When the circular cutter moves,
the detection plate moves between the LED and the photo IC.
The beam of light is then interrupted, and the output level of the photo IC changes. This change in the output
level is read and used as the circular cutter position detection signal.
Circular cutter
Auto cutter home position sensor
Rev. 2.00
Auto cutter detection plate
LED
- 134 -
SRP-275
+5V
Photo transistor
Detection signal
GND