Ricoh Di-C1.5a Manual page 145

This motor drives three drums.
It does not drive the development units.
The drum gear position sensor detects when the motor is not
working.
It also makes sure that the drum gear is at the correct angle when
printing starts.
Slide 145
The function of the gear position sensor is similar to the sensor for black.
The motor drives all three color drums. This reduces color alignment errors.
The two gear position sensors (K, CMY) work together. Both gears must be at
home position at the start of the job. If there is an error, the position of the black
gear is corrected to match the position of the CMY gear.
The mechanism is initialized after every 30 jobs.
Drum Drive - CMY
145
Di-C1.5 Training
Drum Drive
Motor - CMY
Drum Gear Position
Sensor - CMY