Abstract: An electrophotographic printer including a paper storage portion for storing paper sheets to be printed, a paper discharge portion for receiving the paper sheets which have been discharged to the paper discharge portion upon completion of printing of the paper sheets and a printing portion provided with a photosensitive member, a corona charger, an exposure device, a developing device, a transfer charger, a cleaning device and a fixing device, in which when the paper storage portion, the paper discharge portion and the printing portion are projected over a plane for installing the electrophotographic printer, first, second and third projected regions are, respectively, occupied, by the paper storage portion, the paper discharge portion and the printing portion such that at least one of the first, second and third projected regions is contained in at least either one of the remaining two of the first, second and third projected regions.

Abstract: A multiple-unit type copying apparatus having an apparatus housing divided into a plurality of units including an optical system unit in which an optical system and a driving device are incorporated and which is openably provided so as to be opened about its one end portion relative to the remaining units. The copying apparatus further includes a connector for coupling the driving device with a power source circuit, a coupling detecting device for detecting a coupling state of the connector and a power supply cut-off device for cutting off power supply to the remaining units when it has been found by the coupling detecting device that the connector is in an uncoupled state.

Abstract: An automatic duplex copying type copying apparatus for automatically copying opposite copying faces of an original document onto opposite faces of a copy paper sheet, respectively, including first and second trays for sequentially accommodating first and second copy paper sheets, respectively, an original feeding device for feeding first and second original documents from an original feeding tray to an original platform, a transport device for transporting the first and second copy paper sheets to the first and second trays, respectively, an original returning device for returning the first and second original documents to the original feeding tray and a paper feeding device for feeding the first and second copy paper sheets from the first and second trays, respectively.

Abstract: A metal paper guide is disposed near the transcription section for leading a copy paper into the transcription section. The metal paper guide is grounded in the normal operational mode at the normal humidity condition. When the copying machine is placed in a high humidity condition, the metal paper guide is isolated from the grounded terminal for preventing the leakage of charges supplied on the copy paper through the metal paper guide.

Abstract: A fixing device for fixing images of an original document on a copy material is provided for a plain paper copier. The fixing device comprises a pair of rollers for stressing under pressure the copy material carrying toner powder thereon. The toner powder is tightly adhered to the surface of the copy material to correspond to the images of the original document. In a preferred form, the toner powder is a pressure-fixable developing powder which consists of a wax component and a thermoplastic resin. A developing powder supplier is disposed within a developer powder reservoir for supplying developer powder to a magnet brush. A rotatable cylindrical magnet is provided within said developing powder supplier for generating a non-uniform magnetic field to stir the developer powder within the reservoir.

Abstract: In an electrophotographic copying machine having a reciprocating original carrier, a metal frame having a substantially U-shaped section is fixed to one side edge of a transparent glass platen. A pair of guide rails are provided at both sides of the copying machine body, one for slidably accommodating the U-shaped metal frame and the other for slidably supporting the bottom wall of the transparent glass platen at the opposite side edge to the side where the U-shaped metal frame is fixed.

Abstract: In an electrophotographic copying machine having a travelling original carrier or a travelling optical exposure system, a feedforward clutch and a reverse clutch are selectively operated by a cam mechanism associated with a control clutch and by latch mechanisms associated with the control clutch and controlled by one solenoid.