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[m] Paper alignment plate home position sensor (SBHPS)
SBHPS is the sensor same as the transport entry port sensor (PIS).
The alignment plate home position is detected.
The light path is interrupted when in the home position.
The signal is passed to the CPU (IC9-72 pin) through the noise filter of R9 and C13.
Logic of the signal inputted to the CPU: Home position not detected
The alignment plate home position is detected.
The light path is interrupted when in the home position.
The signal is passed to the CPU (IC9-72 pin) through the noise filter of R9 and C13.
Logic of the signal inputted to the CPU: Home position not detected
®
H, Home position detected
®
L
R43 is the current limiting resistor of LED. R61 is the sensor load resistor.
[n] Paper reverse sensor (PRS)
PRS is the transmission type sensor where the LED and the photo transistor are separated.
The document presence in the reverse section is detected.
The light path is interrupted when document detected.
The light emitting side is illuminated by the output of the CPU (IC 9-50 pin) through Q9.
IC 9-50 pin logic: Light emitting
The document presence in the reverse section is detected.
The light path is interrupted when document detected.
The light emitting side is illuminated by the output of the CPU (IC 9-50 pin) through Q9.
IC 9-50 pin logic: Light emitting
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H, Not emitting
®
L
R91 is the current limiting resistor of the light emitted diode.
On the other hand, the signal is inputted to the CPU (IC-9-74 pin) through the noise filter of R8 and C12 and the comparator (IC 4-1).
The reference voltage of the comparator is determined by division of the power voltage (+5V) with R85 and R86.
R88 is used to provide hysteresis to the reference voltage.
R60 is the pull-up resistor of the comparator output.
C11 in the signal line is used to absorb noises. R90 is the load resistor of the photo transistor.
Logic of signal inputted to the CPU: Document presence
On the other hand, the signal is inputted to the CPU (IC-9-74 pin) through the noise filter of R8 and C12 and the comparator (IC 4-1).
The reference voltage of the comparator is determined by division of the power voltage (+5V) with R85 and R86.
R88 is used to provide hysteresis to the reference voltage.
R60 is the pull-up resistor of the comparator output.
C11 in the signal line is used to absorb noises. R90 is the load resistor of the photo transistor.
Logic of signal inputted to the CPU: Document presence
®
H, DOcument empty
®
L
Paper alignment plate
home position
sensor
home position
sensor
Paper alignment plate home position sensor input circuit
SB
(SBHPS)
Paper reverse sensor input circuit
Paper reverse sensor
(PRS)
(PRS)
PRL
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