High-voltage power-supply PCA The high-voltage power supply applies positive or negative voltage biases to the following components: ● Primary charging roller ● Developing roller ● Transfer roller ● Static charge eliminator ● Fuser film Figure 1-7 High-voltage power-supply PCA Fuser Fuser film DC controller High-voltage power supply Pressure roller Primary charging bias circuit Cartridge To primary charge roller To developing roller Developing bias circuit Photosensitive drum Static charge eliminatior bias circuit Static charge eliminator Transfer roller Transfer bias circuit The DC controller controls the high-voltage power supply to generate the following biases.
● Primary charging bias The primary charging bias is used to charge the surface of the photosensitive drum evenly to prepare for image formation. The primary charging bias circuit generates the bias. ● Developing bias The developing bias is used to adhere toner to an electrostatic latent image formed on the photosensitive drum. The developing bias circuit generates the bias. ● Transfer bias The transfer bias is used to transfer the toner from the photosensitive drum onto the paper. The transfer bias circuit generates the bias. The transfer bias circuit also generates the reverse bias to clean the transfer roller. ENWW Engine control system 13