Toshiba 3511, 4511 manual Functions

11

11.2 Functions

(1)Drum

Drum is made of a cylindrical aluminum base coated with thin film of organic photoconductive sub- stance.

Photoconductive object becomes insulative (high electrical resistance) when it is not exposed to lights and becomes conductive (low electrical resistance) when it is exposed to lights. This object is called photoconductor.

(2)Main charger

Main charger consists of a metal rod case having insulated blocks at the both ends with the charger wire attached and the grid is set between them.

When high voltage is applied to the charger wire, the surrounding air is charged (ionized). Then a flow of the ionized air into the drum applies the drum a charge as well. This phenomenon is called “corona discharge” and a control bias is applied to the grid to control the charging amount. Negative charge caused by the corona discharge is applied to the drum surface evenly in dark places. Charger wire is equipped with an automatic wire cleaner to clean the wire.

(3)Drum thermistor

Since the photoconductive characteristic of the drum surface changes depending on the tempera- ture of the drum surface, the drum thermistor detects the temperature of the drum surface and controls to gain the charging potential according to the environment.

(4)Drum cleaner

(a)Cleaning blade

This blade is pressed against the drum surface with a constant force by pressure springs, and scrapes off the residual toner on the drum surface. Also it removes the positive charge on the photoconductive drum by applying negative charge on the blade.

(b)Recovery blade

This blade catches the toner scraped off by the cleaning blade.

(c)Toner recovery auger

This auger carries the residual toner scraped off to the toner bag.

(d)Drum cleaner brush

This brush roller prevents the residual toner and foreign matter adhering to the drum surface.

e-STUDIO3511/4511 DRUM RELATED SECTION 11 - 2 November 2003 © TOSHIBA TEC