| 摘要 |
This invention relates to an electrophotographic copying and printing apparatus having copying function and printing function. An object of the invention is to provide an electrophotographic copying and printing apparatus comprising a photosensitive member having the photosensitivity to electrical charge in positive and negative polarities, an electrically charging unit for charging the surface of the photosensitive member in either positive or negative polarity, an exposure unit for copying including an optical system by which an optical image corresponding to an image of an original placed on a support table therefor is irradiated onto the charged surface of the photosensitive member, an optical image scanning unit for printing including an optical system which irradiates a recording region corresponding to a record signal onto the charged surface of the photosensitive member, and a single developing unit, so that the charge polarity of the photosensitive member is inverted of positive and negative in the copying mode and printing mode and the single developing unit can perform normal development in the copying mode and reverse development in the printing mode, thus being small-sized, inexpensive to produce, and easy to operate.
|
