Abstract: An electrophotographic apparatus for obtaining duplicated copies based on an image-like information comprising a light source, a photosensitive charge retentive member, a development device, an emissive fixing device and a cleaning device. The emissive fixing device comprises a radiation member for generating light having a wavelength which is at least mainly in a region other than the wavelength region of light to which the charge retentive member is sensitive and heats toner particles.

Abstract: An electrophotographic apparatus comprising a sheet like document feed device for feeding a sheet like document through an exposure and scanning section at a constant speed, an optical system for illuminating the document at the exposure and scanning section and projecting a document image onto a rotatably arranged photosensitive drum to form an electrostatic charge image on the drum, a developing device for developing the charge image with toners to form a toner image, a transfer roller for transferring the toner image onto a record paper which is supplied from a paper cassette by means of a paper feeding device, and means for shifting operational timings of the document feed device and optical system and/or the paper feeding device with respect to the rotational movement of photosensitive drum, whereby the duplicated toner image may be formed at any desired position on the record paper viewed in its feeding direction.

Abstract: An electrophotographic apparatus which includes a rotating photosensitive drum on which an electrostatic charge latent image is formed; a developing device for developing the latent image with toners to form a toner image on the drum; a transfer roller for transferring the toner image onto a record paper and arranged movably with respect to the drum; and a record paper detector for detecting a paper jamming to produce a paper jam signal. The rotation of the drum is stopped and the transfer roller is moved away from the photosensitive drum in response to the paper jam signal so as to make it easy to remove the jammed paper, and the transfer roller is moved into an initial operative position after the ddrum has rotated by such an angle that residual toners and electrostatic charge on the drum pass through the transfer roller.

Abstract: The electrophotographic apparatus for forming one or more copies of a document has a photosensitive drum rotatably arranged for forming an electrostatic charge latent image and a developing device for developing the latent image into a toner image. A transfer roller is rotatably arranged for transferring the toner image onto a record paper which is supplied between the drum and transfer roller. A pair of arms are provided each of which rotatably support a respective end of a shaft of the transfer roller through a bearing and which is slidably inserted in a recess formed in respective arms in a radial direction of the drum. Furthermore, a pair of coiled springs are each respectively provided on the respective arms and surround the bearings in such a manner that the transfer roller is forced resiliently to displace toward the drum.

Abstract: A method and apparatus to detect the toner concentration of two component dry developer comprising toner and carrier includes the use of a toner catcher having a conductive member and which is capacitively charged. The developer is applied to the catcher, which traps the toner to determine the toner content.

Abstract: An electrophotographic apparatus for forming any desired number of copies of a document from the same and single electrostatic charge latent image once formed on a photosensitive drum. The apparatus has a copy number set dial and a copy number counter for storing a desired copy number set by the dial. A control circuit for produces a load signal which serves to transfer the copy number set in the dial into the copy number counter. After the copy number has been transferred from the dial into the counter any desired copy number to be formed for a next document can be set in the dial. In a preferred embodiment the load signal is generated after a duplicating operation for a first copy has been initiated.

Abstract: An illuminating device for use in a copying apparatus, a facsimile apparatus, and the like in which a document is illuminated and imagewise exposure of the illuminated document is effected comprises an illuminating fluorescent lamp having an elongated tube, and a mask having a plurality of apertures formed therein, whereby the mask is provided around the tube in closely contact therewith and extending substantially over the whole length of the tube and said openings are so configurated that the document is illuminated with a uniform light distribution.

Abstract: An electrographic apparatus for selectively producing, on a latent image holding member including a first electrostatic latent image produced thereon by a first charge, a second electrostatic latent image composed of a second charge which is negative with respect to the first electrostatic latent image and which is opposite in polarity to the first electrostatic latent image. The apparatus includes a device for selectively applying to the latent image holding member a second charge which is opposite in polarity to the first charge.

Abstract: An electrographic process of producing, on a dielectric coated record medium, an electrostatic copy latent image by modulating a flow of corona ions with the aid of an electrostatic latent image which has been produced on a photoconductive photosensitive screen having a number of openings. The process is characterized by making a ratio K of a maximum surface potential V volts of the electrostatic copy latent image produced on the dielectric coated record medium to an intensity of the electric field E volts/mm established between the photoconductive photosensitive screen and the dielectric coated record medium, i.e. K=V/E smaller than about 0.18 for the purpose of preventing enlargement of dots of the copy picture image.

Abstract: A corona discharge device for electrographic apparatus which makes use of a drum-shaped photosensitive screen. The device is provided with a corona electric field establishing electrode extending in parallel with a corona discharge wire and supplied with an electric potential which is intermediate the electric potential of a field electrode and the electric potential of the corona discharge wire.

Abstract: An electrophotographic apparatus particularly suitable for printing a plurality of duplicated copies from each of a plurality of sheet-like documents comprising a sheet-like document feeding device for feeding the sheet-like document at a constant velocity, an optical system including an illumination lamp and a projecting lens for exposing and scanning the document during the traveling of the document, a photosensitive drum for forming a latent image corresponding to the document image and retaining the latent image for a relatively long time period, a device for developing the latent image with toner particles, a device for transferring the toner image onto a record paper and a device for fixing the toner image on the paper. After the latent image has been once formed on the photosensitive drum the given number of duplicated copies are formed by repeatedly effecting the development, transfer and fixing operations.

Abstract: An electrophotographic apparatus for forming or printing any desired number of copies of a document from the same and single electrostatic charge latent image comprisinga photosensitive member such as a photoconductive drum which is rotated at a constant velocity;a corona charger for uniformly charging the photosensitive drum;a document feeding device for advancing the document through an exposure-scanning portion at a constant speed;an optical device for projecting an image of the document at the exposure-scanning portion onto the drum to form an electrostatic charge latent image thereon;a developing device for developing the latent image with toner particles to form a toner image;a transferring device for transferring the toner image onto a record paper;a fixing device for fixing the toner image on the record paper to form a final copy;a clock pulse generator for producing clock pulses in synchronism with the rotation of the photosensitive drum;master and slave timing pulse generators for receiving the cloc

Abstract: An electrophotographic apparatus for exposing and scanning a document placed on a fixed copy board by a scanning optical system. A sheet feed device is provided near the fixed copy board for feeding and exposing a sheet-like document. The optical system corresponding to the sheet feed device comprises at least a part of the scanning optical system.

Abstract: A device for manufacturing a photosensitive screen comprising a vapor supply source and a mesh-shaped electric conductive substrate arranged above the vapor supply source along at least one portion of a circular plane having a center located at the vapor supply source.

Abstract: An electrostatic latent image developing device capable of converting an electrostatic latent image to a visible image with the aid of a toner containing magnetic material is disclosed. The device comprises means for making the moving speed of the toner higher than the travelling speed of the electrostatic latent image.

Abstract: A record sheet cutter control device which can cut a record sheet after a normal record sheet feeding operation has completely been stopped. The device comprises means for involving a difference in time between a signal for stopping the operation of a record sheet feed roller and a signal for starting the operation of a cutter.

Abstract: A screen drum type electrographic apparatus which can alleviate widening of a dot constituting a picture image is disclosed. A ratio of a feeding speed of a record medium to a peripheral speed of a screen drum is selected to a range shown by a hatched region in FIG. 3 on the basis of theoretical calculation treatments illustrated in FIG. 2.

Abstract: An electrographic apparatus comprising a photosensitive screen composed of an insulating layer, two electrically conductive layers coated on opposite sides of the insulating layer and a photosensitive layer coated on one of said electrically conductive layers, and a bias electric source connected between the two electrically conductive layers and producing, on a dielectric coated record sheet, an electrostatic latent image corresponding to an image to be reproduced is disclosed. The apparatus comprises means for adjusting a bias voltage supplied from the bias electric source and applied between the two electrically conductive layers.

Abstract: An electrographic apparatus which makes use of a screen drum composed of a mesh-shaped photosensitive screen. The apparatus comprises one corona discharge device, a corona voltage source circuit including a corona voltage source switch connected to an input side of said corona voltage source circuit and a polarity change-over switch connected between said corona voltage source circuit and said corona discharge device. A first step of uniformly charging said photosensitive screen and a second step of charging a dielectric coated record sheet with an electrostatic charge image corresponding to an image to be recorded are effected by one corona discharge device only.

Abstract: An electrographic apparatus for producing, on a dielectric record sheet, an electrostatic charge image corresponding to a manuscript image to be recorded is disclosed. The apparatus comprises a shutter arranged in a light path for projecting the manuscript image onto a photosensitive screen and adapted to be opened only when an electrostatic latent image corresponding to the manuscript image is produced on the photosensitive screen.