Kyocera FS-1050 Service Manual - Page 69

(3) Development The latent image constituted on the drum is developed into a visible image. The developing roller A contains a 3-pole (S-N-S) magnet core B and an aluminum cylinder rotating around the magnet core B. Toner attracts to the developing roller A since it is powdery ink made of black resin bound to iron particles. Doctor blade C, magnetized by magnet D, is positioned approximately 0.3 mm above the developing roller A to constitute a smooth layer of toner in accordance with the roller revolution. C Magnetism N 0.1 mm S E S D 0.3 - 0.4 mm N S AB F Developing bias output 275±5 V DC + AC Bias board YC-B Engine board HVCLK YC302-8 YC11-5 Figure 4-1-8 Development The developing roller A is applied with the AC-weighted, positive DC power source. Toner E on the developing roller A is given a positive charge. The positively charged toner E is then attracted to the areas of the drum F which was exposed to the laser light. (The gap between the drum F and the developing roller A is approximately 0.3 mm.) The non-exposed areas of the drum F repel the positively charged toner as these areas maintain the positive charge. The developing roller A is also AC-biased to ensure contrast in yielding by compensating the toner's attraction and repelling action during development. FS-1050 4-10