Charge Corona Unit - Ricoh FT4460 Service Manual

2.2 CHARGE CORONA UNIT

The charge corona unit consists of the charge corona wire [A], the grid mesh
[B] and the charge wire cleaner [C].
The applied voltage of the charge corona wire is constant but the surface
potential of the drum rises in proportion to the number of copies made. A volt-
age corresponding to the drum surface potential is applied to the grid [B] to
achieve consistent copy quality. The amount of compensation is determined
by the ID sensor (Vrp/Vsg).
The flow of air around the charge corona wire [A] may deposit paper dust or
toner particles on the corona wire. These particles may interfere with charging
and cause low density bands on copies. The wire cleaner [C] cleans the
corona wire when the operator slides the corona unit in and out.
2-5
28 February 1989