Ricoh FT5034 Service Manual page 78

4. Cleaning Blade
The cleaning pressure mechanism is shown to
the right. When the cleaning solenoid is
energized, it turns the cleaning solenoid lever
clockwise (rear view). Due to the pull of the
cleaning blade pressure spring, the pressure
arm also turns clockwise and pushes the
cleaning blade lever up. The cleaning blade
holder then rotates and the cleaning blade
presses against the drum. Blade pressure is
limited by the pressure spring.
The cleaning blade is mounted by a single
swivel screw at its exact center of mass. With
this type of mounting the blade sets parallel
and applies even pressure automatically. Also,
a single pressure spring is used, as the blade
does not need a spring at each end to apply
even pressure if it is mounted in this way.
The blade scraper is mounted in contact with
the bottom side of the cleaning blade. When
pressure is applied to the cleaning blade, it is
forced forward and bends at its outer edge.
When pressure is released from the blade, it
snaps back to its original shape. At this time,
the mylar of the blade scraper scrapes off the
excess toner and paper dust from the trailing
edge of the blade. This helps to maintain
efficient cleaning.
The blade pressure is released when there is
no key input for 15 minutes, when a paper jam
occurs, when the energy save mode starts, or
when the door safety switches are open.
The blade scraper also prevents toner from
scattering inside the copier by keeping toner
inside the cleaning unit.
Pressure Arm
Pressure
Spring
Cleaning
Solenoid
- 77 -
Stepped Bushing
Cleaning Blade
Blade Lever
Blade Scraper