Service Manual
Operating Principles
2.1.3.1 Main Motor Functions and Control
The power of the main motor drive is used OPC drum drive, developing drive, fusing drive, and
paper feeding drive.
Figure 2-25 shows the main motor drive circuit. The main motor is a 4 phase stepping motor. This
motor is controlled by the CPU on the engine controller board (MC
MCU
PIJ14
Main Motor
4
B
/B
Figure 2-25. Main Motor Drive Circuit
2.1.3.2
Sensor and Exit Sensor
The
sensor has three functions. One function of the
sensor is to detect the top edge of
the paper. This engine starts printing by detecting the signal.
One function is paper size detecting. This printer detects on time of
sensor, while paper is
feeding. This time is long, while longer paper is feeding. This time is short, while shorter paper is
feeding.
One function is paper jam and feed jam detecting to combine for exit sensor.
If the
sensor does not turn on at paper feeding, it will be judged feed jam. The feed jam is
the
condition that a paper jam has occurred in the feed process.
If the following conditions are detected, it will be judged paper jam. The paper jam is when paper
is jammed in printing process area.
■
The
sensor or the exit sensor is on when the power is on or the front cover is closed.
■
The
sensor or the exit sensor is not turned on/off within the specified time. (Refer to
following timing chart.)
Feed or Pickup Solenoid ON
[sec.]
E 2
EXIT Sensor
E2: Cassette
Optional Cassette Feed=6.33
MS I Feed=3.48
Figure 2-26.
Sensor and Exit Sensor On/Off Timing
Rev.
2-15
