Ricoh Aficio SP 5100N, Service Manual

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Engine Hardware Specifications
G186 6-10 SM
Paper Sensing on the By-pass Tray
By operation of the actuator on the by-pass tray, by-pass tray sensor (Photo interrupter) on
the engine board transmits paper set information to the CPU. It reads the D0 Bit of CPU for
recognizing paper in by-pass tray, and paper is fed from by-pass tray if there is paper.
Paper Feeding/ Width Toner Cartridge Sensing
When paper passes the actuator (feed sensor part), it detects the signal of the photo
interrupter, conveys the paper feeding state to the CPU, and then sprays the image data
after a certain amount of time.
If the feed sensor isn't detected within 1sec. after paper is fed, the paper Jam0 (CPU #_ )
occurs and the fact whether the developer is inserted or not is detected with the same
principle. After the developer is mounted, the actuator is operated. The signal from the
photo interrupter is detected when it is passing the actuator of the sensor part. That is the
developer ID sensing.
Paper Exit Sensing
The exit sensor and actuator at the paper exit unit detect whether paper exits the machine.
Detection of the on/off time of the exit sensor is read by the D2 Bit of the CPU. JAM2 is
indicated.
Cover Open Sensing
The Cover open sensor is located on the front cover. After the front cover is opened, +24V
(supplied to DC fan, Solenoid, Main Motor, Polygon motor part of LSU and HVPS), is cut off.
Cover-open detection is operated by the D0 bit of the CPU, and the developer ID sensing is
operated by the D7 bit of CPU.
DC Fan/ Solenoid Driving
DC Fan is controlled by the D6 bit of CPU.
When it is high, the fan is driven by turning on the TR, and it is off when the sleep mode is
selected.
There are two solenoids, and they are driven by paper pick-up and by-pass tray signals,
turning on or off by the D4 bit of the CPU, and the driving time is 300 ms. The diode
protects the driving TR from noise pulses, which can occur when the solenoid is
de-energizing.
Motor Driving
The motor driving circuit is formed when the Driver IC is selected in the first place. The
A3977 Motor Driver IC is used in this case. But the resistance Rs value of sensing and the
voltage value of the V reference can be changed by motor driving voltage value. The motor