Detailed Descriptions; Paper Size And Paper Tray Detection - Ricoh G157 Service Manual

PAPER SIZE AND PAPER TRAY DETECTION

2. DETAILED DESCRIPTIONS

2.1 PAPER SIZE AND PAPER TRAY DETECTION
[A]
G389D901.WMF
A printed circuit board [B] located at the far end of the right paper tray rail is
comprised of four photosensors. Three photosensors on the front side [E][F][G] are
the paper size sensors. The remaining photosensor, located towards the back of
the printed circuit board, is the paper tray sensor [D]. The paper size sensors
detect the paper size in the paper tray. The paper tray sensor detects the paper
tray.
An interrupt [I] is physically attached to the front plate [A] and can block (interrupt)
the paper size sensors. This interrupter has an opening on it [H]. The interrupter
can actuate (interrupt) up to two sensors at one time.
The paper tray has another interrupter [C] located on the rear right corner of the
tray. This interrupter actuates (interrupts) the paper tray sensor. When the paper
tray is correctly set in the paper tray unit, the paper tray sensor is constantly
blocked (interrupted).
The table below lists the sensor activation patterns and corresponding detected
paper sizes.
Paper Size Sensor
[G]
Interrupted
Not interrupted
Interrupted
Not interrupted
Interrupted
G389
[C]
[B]
[F]
Not interrupted Not interrupted
Not interrupted
Interrupted Not interrupted
Interrupted Not interrupted
Not interrupted Not interrupted
[D]
Paper Tray
[E]
Interrupted
Interrupted Interrupted
Interrupted
Interrupted
Interrupted
10
Paper Size
Sensor
[D]
Executive
Letter
[E]
[F]
[G]
[H]
[I]
B5
B5
A4
SM