Abstract: In a transfer method of a colored image, the process speed is initially properly set in accordance with the size of a copy paper sheet to be used. The transfer voltage is then changed in accordance with the process speed. After these processes, a colored toner image formed on a photoconductor is first transferred onto an intermediate transfer medium and then further transferred onto the copy paper sheet.

Abstract: An electrophotographic apparatus having: a developer unit that has a magnetic developing roller for applying toner to electrostatic latent image areas formed on the surface of a photoconductor and that has a shutter which is closed to regulate the distribution of the toner to the photoconductor, a developing bias voltage for controlling adherence of the toner to the photoconductor being applied to said developer unit; and a bias voltage source for applying, when the shutter of the developer unit is closed, a developing bias voltage of the level between 0V and the developing bias voltage applied when the shutter is opened, thereby preventing blank spots from appearing in transferred images without increasing image-overtoning and also preventing damages from being caused to the surface of the fuser rollers of a fuser unit.

Abstract: A corona discharging unit comprises a control grid to which a diode is attached and a high voltage AC power is applied to its discharge line. A single unit of this design with a single power source, when used in an electrophotographic copying machine with a rotating photosensitive drum, can perform more than one of the functions required in a copying process such as preliminary charging of the drum, transferring images, discharging and cleaning.

Abstract: An electrophotographic recording apparatus which repeats the development of an electrostatic latent image corresponding to the original, which is formed once on an image supporting means, with a toner and the succeeding transfer of the resulting toner image to a transfer substance, thereby producing a number of copies of the original, wherein said recording apparatus comprises a transferring means having at least one corona charger connected to a high AC voltage source to repeatedly conduct transfer and discharge, regions in which said transfer and said discharge are carried out, respectively, being adjacent to each other.