| 摘要 |
PURPOSE:To improve the quality of images when envelopes are passed. CONSTITUTION:When a paper size detecting sensor 13 detects that envelopes are passed, a switching circuit 102 changes the output of an output circuit 101, that is a bias voltage to be applied to a development roller 51, in a power pack 10 and a switching circuit 112 changes the output of an output circuit 111, that is, the transfer current to run toward a photoconductor 1 from a charge wire 71 in a power pack 11 by means of a CPU 12. A toner sticking amount and a transfer current are set to be 1.05-1.15 times and 1.6-2.1 times, respectively, those at the time of passing normal cut paper sheets. Consequently, without causing stains in the skin of paper the transfering efficiency is improved and toner density is heightened and good printing quality is obtained. |
