| 摘要 |
PURPOSE:To prevent development fogging which caused at the time when the linear speed of a photoconductor drum of an image forming apparatus is changed to slow linear speed by switching the image forming mode. CONSTITUTION:An image forming apparatus has two modes: a normal image forming mode and a decreased speed image forming mode to retard the linear speed of a photoconductor drum or the fixing speed to carry out fixing on thick paper or form lustrous images. When the decreased speed image mode is set by changing from the normal image forming mode, development bias voltage to be applied to a development sleeve 31S is changed by CPU control to stop development. Practically, a. c. bias voltage is turned off and d.c. bias voltage is decreased to 0 to 400V. |
