Around The Drum - Ricoh FT5034C Service Manual

4.6 AROUND THE DRUM

4.6.1 Mechanical Parts
1. Overview
The drum drive belt turns the drum pulley when the main motor is on. The rear drum
flange is secured by a screw on the drum shaft and the drum spring presses the
drum onto the rear drum flange.
Drum Spring
So, the rotation is transmitted from the drum drive pulley to the drum shaft and then
through the rear drum flange to the drum.
2. Drum Charge
In the dark the corona wires generate a corona
of positive ions when the C/B power pack
applies a high positive voltage (+5.0 kV ~ 7.5
kV).
The selenium coating receives a uniform
positive charge (700 ± 50 V) as it rotates past
the corona unit.
The main motor fan provides a smooth flow of
air to the interior of the charge corona unit to
prevent uneven build-up of positive ions.
The diameter of the charge corona wire is 0.08
mm and the wire surface is coated with carbon.
The wire cleaner cleans off any particles on the
wires when someone pulls out the corona unit
and pushes it back.
Drum Shaft
Rear Drum Flange
- 44 -
Drum
Charge
Corona Unit
Wire Cleaner
Drum Drive Belt
Drum Drive Pulley
Power Pack C/B
Main Motor Fan