Sensors; Paper Jam Sensing - Kyocera Ecosys FS-600 Service Manual

Operation theory
Operation overview

Sensors

A photo penetration type sensor is used for the paper feed sensor, registration sensor,
and the exit sensor (fuser).
While paper is not present as shown in !, the reflector at one end of the sensor's
actuator is normally seated inbetween the photo transmitter and the sensor.
While the paper is present, the reflector is pushed up by the paper and the light is
interrupted as shown in ", thus triggering the sensor.

Paper jam sensing

The registration sensor and the exit sensor (at the fuser) keep track of the paper passing
through the paper path by metering the time of period elapsed since the registration
sensor is triggered.
Paper must also pass the registration sensor when it comes from the paper cassette in a
predetermined period of time that begins with energizing of the feed clutch (FEDDR).
In case the trailing edge does not release the sensor at the exit sensor in the
predetermined period of time, the engine controller determines that paper is jammed. The
JAM
engine controller stops printing and call the user's attention by flashing the indicator.
When the jammed paper is removed and the top cover or the paper cassette is closed,
the printer resumes printing. If paper was jammed after clearing the exit sensor, the same
page will not re-printed.
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FS-600/FS-680