Abstract: A printer including a photosensitive drum on which a toner image is formed, a plurality of transfer wires held in facing relation to the drum, and a static-eliminating wire located downstream from the transfer wires. Transfer currents are conducted through a selected one or more of the transfer wires in accordance with the thickness of recording paper used in the printer.

Abstract: A developing apparatus develops a latent image formed on a latent image carrying body with a developer. The developing apparatus includes a developing unit having a means for supplying the developer to the latent image carrying body to develop the latent image on the latent image carrying body and a developer housing for accommodating the developer. A developer storage box stores the developer which is to be supplied to the developing unit. The developer storage box is detachably mounted on the developing unit and has a volume substantially the same as a volume of the developer which can be accommodated in the developer case of the developing unit. The developer in developer storage box is supplied to the developing unit.

Abstract: An automatic cleaning method for cleaning an electrifier of an image forming apparatus. A drive mechanism moves the cleaning member to clean the electrifier. An electrification time measuring section measures an electrification time of the electrifier after the last cleaning of the electrifier. A medium detecting section discriminates whether or not a medium is located in an image forming station. A control section controls the drive mechanism to render the cleaning member to clean the electrifier when a medium is not present in the image forming station after the measured electrification time reaches a determined time. The result is that automatic electrifier cleaning can be done at an appropriate preset timing, causing an elongated service life of the electrifier.

Abstract: The invention provides a double-sided printing apparatus which includes a first image forming process unit, a second image forming process unit, a first fixing station, a second fixing station and a transport system all disposed in a first housing. The transport system includes a transport direction changing element which contacts with one of surfaces of a medium to change the transporting direction of the medium so that the medium is sent out to the second fixing station. While the medium is transported in a substantially vertical direction in the single double-sided printing apparatus, the height of the transport path of the medium is suppressed so as not to become very high, thereby miniaturizing the apparatus.

Abstract: A fixing unit is provided with a fixing heat roller, a first reel supplying a cleaning member which cleans a surface of the fixing heat roller, a second reel taking up the cleaning member from the first reel, and a unidirectional clutch mechanism intermittently driving the second reel in a direction to take up the cleaning member using rotation of the fixing heat roller.

Abstract: A developing device for developing an electrostatic latent image with a two-component developer comprises a developer container (46) including a developer-accumulating chamber (50), and a developer-agitating chamber (56) provided above the developer-accumulating chamber. A communication passage (64) is provided between the developer-agitating chamber and the developer-accumulating chamber, and is opened to the developer-agitating chamber to define an overflow opening for the developer. The device also comprises a developer-carrying body (48) provided in the developer-accumulating chamber of the developer container, and the developer-carrying body is exposed to face an electrostatic latent image carrying body, and brings the developer from the developer-accumulating chamber to a facing zone therebetween for development of an electrostatic latent image formed on the electrostatic latent image carrying body.

Abstract: An image forming apparatus including a plurality of developing units each having a developer storage portion for accommodating a developer; a plurality of feeding devices for discharging used developers from the respective developing units; and a single collecting device for collecting the used developers discharged by the respective feeding device.

Abstract: An electrostatic recording system using a dielectric belt for conducting electrification of a sheet of paper and a transfer belt so that the sheet of paper is not wound and caught by a photoconductor drum, and a transfer voltage can be lowered so as to smoothly separate the sheet of paper from a transfer belt. The electrostatic recording system applies a voltage to only the dielectric belt at a stage before the sheet of paper 3 is attracted to the dielectric belt 10 and applies voltage to the sheet of paper 3 conveyed to the dielectric belt, and to the dielectric belt 10 while the sheet of paper and the belt are mutually superposed.

Abstract: To provide a photo-sensitive drum having excellent properties which are not at all inferior to those of the prior art photo-sensitive drums assembled with a larger number of parts, capable of being easily manufactured at a reduced production cost. A blank tube 23d consisting of a cylinder section 23a, a center axis section 23b arranged within the cylinder section 23a concentrically therewith and a plurality of rib sections 23c for rigidly connecting the cylinder section 23a with the center axis section 23b is integrally formed through extrusion or draw-forming.

Abstract: A plurality of electrostatic recording units (Y, C, M and B) are arranged in series along a recording medium moving path. Each electrostatic recording unit includes an electrostatic latent image carrier (48), a developing unit (54, 54') arranged on the upstream side of the electrostatic latent image carrier, and a cleaning unit (60) arranged on the downstream side. The developing unit includes a developer holding container (66) having a developer storage portion (70) and a developer agitating portion (76) located above the developer storage portion. The developer agitating portion is communicated with the developer storage portion via a communicating path (82). The cleaning unit (60) of one of the adjacent electrostatic recording units is disposed adjacent to the developer storage portion (70) of the developer holding container (66) composing a portion of the developing unit (54, 54') of the other electrostatic recording unit.

Abstract: A toner image transferring device is used to electrostatically transfer a charged toner image from a roller to a sheet of paper. The device includes a transfer charger for giving the paper an electric charge. A charge eliminator is located next to the roller for partially eliminating the electric charge from the paper. The charge eliminator is positioned to be adjacent to the paper and the roller, but displaced from the transfer charger. Paper passes through the device such that the paper is in contact with the roller when passing over the transfer charger, thereby optimizing the transfer of the toner image from the roller to the paper.

Abstract: A magnetic brush developing apparatus, comprising: a development container (102) for containing a developer; a magnet (122) stationarily located in the development container and having magnetic poles radially provided on a plurality of points; a rotational sleeve (121) arranged to cover the outer circumference of the magnet and rotatably driven to carry the developer in the development container to an image carrying body (131); and a blade (123) arranged opposite to the sleeve to restrict the amount of the developer which is carried by the sleeve. Two of the magnetic poles are a developing magnetic pole (Pd) facing opposite to the image carrying body (131) and a developer transfer magnetic pole (Pt) located between the developing magnetic pole (Pd) and the blade (123). A magnetic brush of the developer formed on the sleeve (121) by the developer carrying magnetic pole (Pt) has a magnetic flux density.