Stabilizing The Scanning Lamp; Detecting The State (Open/Closed) Of The Adf - Canon iR8500 Service Manual

CHAPTER 2 NEW FUNCTIONS

2.6 Stabilizing the Scanning Lamp

To stabilize the intensity of the scanning lamp, a transformer power PCB has been added,
and the voltage supplied to the inverter power supply has been increased from 38 to 40 V.

2.7 Detecting the State (open/closed) of the ADF

As in the case of the GP605, the ADF uses the open/closed sensor (going ON at 30°) of
its host machine; in addition, on the other hand, it is equipped with an open/closed sensor
(going ON at 5°) inside it. The state (open/closed) of the ADF is checked with reference to
the states of these two sensors (If, for some reason, the state of the ADF sensor cannot be
checked, the state of the sensor in its host machine will be used, as in the case of the
GP605).
Open/closed sensor (ADF)
• When the ADF Is Opened
The ADF's sensor goes ON when it is lifted to 5° or more [1], causing the host machine
to assume that the ADF is open. At this time, the host machine clears the size of an original
that has automatically been detected, assuming that the original has been removed. Then,
when the ADF is opened farther to 30° or more [2], the sensor in the host machine goes ON,
enabling original size auto detection.
2-10
Open/closed sensor (host machine)
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