Ricoh DD5450 Field Service Manual page 165

Operation
Spring
Shading plate
Standby position during printing
●
Cam is in the bottom position, and the ink roller is
raised up by a spring.
The ink roller up/down sensor is in the state of
photopassing, and it detects that the ink roller
has reached the upper limit position.
In this position, the ink roller is not touching the
drum inner surface.
Ink roller descent
●
The motor rotates, and the cam pushes the ink
roller downward.
When the shading plate rotates, and the
ink roller up/down sensor is in the state of
photointerrupting and detects the ink roller lower
limit position, then the motor stops.
In the lower limit position, the ink roller is pressed
against the drum inner surface, and ink will be
supplied even if the machine performs printing
without paper.
Ink roller ascent (to standby position)
●
The motor rotates, and when the cam reaches
the bottom side, the spring raises the ink roller
up.
When the ink roller up/down sensor is in the state
of photopassing (OPENED), it detects the roller
upper limit position, then the motor stops.
Cam
Ink roller up/down sensor
Ink roller
Ink roller
Drum inner
surface
Chapter 3
Ink roller up/down motor
Cam
Spring
Ink roller
up/down motor
Cam
Shading plate
Photointerrupting
Drum Section
7
３
Ink roller
up/down sensor
Photopassing
Drum inner
surface
Photopassing
163