Stapler Unit Assembly; Functions Of Stapler Sensors/Motors - Lexmark W850n Manual

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Stapler unit assembly

Stapling operation is executed by closing the stapler unit assembly.
The stapler unit assembly, containing the staple motor, the sensor (staple home), the sensor (self priming), and
the sensor (low staple), is activated by the staple motor.
Forward (clockwise) rotation of the motor drives the stapler to staple a set of sheets, and returns the stapling unit
to the home position.
If stapling fails, the motor rotates reversely (counterclockwise) to return the stapler unit assembly to the home
position.
When staples become low, the low staple sensor detects it, and stapling stops automatically, displaying an alarm
message. The message is also displayed when the staple cartridge is not installed.
Sensor (low staple)

Functions of stapler sensors/motors

•
Sensor (stapler carriage HP)
–
A photo-interrupter to detect the stapler home position, rear staple (corner) position, and rear staple
(straight) position
–
It turns "H" (+5 V dc) (light blocking) when the stapler comes to the specified position.
•
Stapler carriage motor assembly
–
A stepping motor to move the stapler unit assembly
–
Clockwise rotation of this motor moves the stapler unit assembly to the rear side, while
counterclockwise rotation moves the stapler unit assembly to the front side.
•
Sensor (low staple) in the stapler unit assembly
–
A photo-interrupter to detect near end of staples
–
It turns "H" (+5 V dc) when 20 staples are left.
•
Sensor (self priming) in the stapler unit assembly
–
A photo-interrupter to detect that staples are at the stapler unit assembly end, and also to detect
failure in stapling
–
"L" (0 V) (light blocking) when stapling is ready
•
Sensor (staple home) in the stapler unit assembly
–
A photo-interrupter to detect the stapler unit assembly home position, and also to detect failure in
stapling
–
This sensor also functions as a trigger to stop the staple motor.
–
It turns "L" (0 V dc) (light blocking) while the stapler unit assembly stays at the home position.
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Finisher Service Manual
Stapler unit motor
Sensor (staple home)
Sensor (self priming)
Stapler unit assembly