Abstract: An image forming apparatus such as a copier includes not only an image erasing lamp having a plurality of point light sources which can be individually switched on and off and input keys by which a region can be specified but also a control unit which is so programmed that the point light sources are switched on and off during a copying process as the copier's photosensitive drum rotates and charges can be cancelled within a frame-shaped region on the photosensitive drum around a boundary defined by the input keys.

Abstract: A developing device for developing a latent electrostatic image for an electrophotographic copying machine includes a cylindrical resilient body such as a fur brush or a roller of sponge for triboelectrically uniformly charging a single component developer of the dry type supplied from a developer storage casing and for coating the developer as a uniform thin layer on a developer carrier such as a developing roller.

Abstract: Disclosed is an electronic printer employing tri-level xerography to superimpose two images with perfect registration during the single pass of a charge retentive member past the processing stations of the printer. One part of the composite image is formed using MICR toner, while the other part of the image is printed with less expensive black, or color toner. For example, the magnetically readable information on a check is printed with MICR toner and the rest of the check in color or in black toner that is not magnetically readable.

Abstract: An electrophotographic print engine with a photosensitive flexible belt stretched over a plurality of rollers in a compact electrophotographic printer such that a developing position on the belt is disposed in a vertical plane, the developing position exposed first to a light on one side of the printer and activated to trace the image of the document to be printed and second passed vertically adjacent at least one toner module extending a decorator roller horizontally to the photosensitive belt on a second side of the printer to create a developed image, the developed image transferred at the upper end of the vertically disposed belt to the downward facing side of a sheet of paper which passes through a fuser to fix the print before the paper is placed facedown in an output tray, permitting the compact printer to create multi-page documents in sequence without manual re-sorting of the document, residual toner wiped from the vertically disposed belt to fall by gravity to a modular collection receptical.

Abstract: An image forming apparatus includes first and second devices selectively operable for developing an electrostatic latent image on a photosensitive member, toner accommodating devices for accommodating developer, detecting devices for detecting toner density in each of developers, a judging device for judging whether the first and second developers have same color, a selecting device responsive to the detecting device and judging device for automatically selecting the second developing device in the case where the toner density in the first developer is less than a specified value and where the toner density in the second developer is not less than the specified value under the judgment by the judging device that the first and second developers have same color, replenishing devices for replenishing toner to each of the first and second developers, and means for activating the replenishing device so as to continuously replenish toner to the first developer until the toner density therein reaches the specified v

Abstract: The present invention relates to an image forming apparatus with a developing device in which first and second detecting elements are provided respectively at opposite ends of the device to detect that substantially same amounts of developer are present in both ends. By this, the image forming apparatus is permitted to start image formation only when the developer is evenly dispersed in the both ends of the device.

Abstract: An image forming apparatus includes a main assembly having a developing position, an opening for receiving and delivering developing devices and developing device transportation passage for communicating the developing position and the opening; a developing device accommodating device for accommodating a plurality of the developing devices and for supplying them to the opening; a detecting device for detecting a malfunction of an image forming operation; and a device for transporting the developing device to either the main assembly or the developing device accommodating device in response to detection by the detecting device.

Abstract: An electrostatic recording appartus having a thermally fixing apparatus and an image forming case adapted to accomodate a unit having a toner container disposed adjacent to a thermally fixing apparatus. An open space is provided between the wall of the image forming case and the wall of the toner container. At the upper and lower portions of the open space, vent ports are preferably provided. Heat insulating material is effectively applied to the walls defining the open space.

Abstract: An apparatus which develops an electrostatic latent image recorded on a photoconductive member used in an electrophotographic printing machine. The apparatus employs a developer material which ages during the life of the electrophotographic printing machine. Carrier granules are added to the developer material to extend the life of the developer material. When the quantity of developer material exceeds a predetermined quantity, developer material exits therefrom through an exit port. A magnetic flux field is generated in the region of the exit port to form a carrier bead curtain which prevents the passage of toner particles therethrough while permitting developer material and carrier granules to exit therefrom.

Abstract: An image forming apparatus has a main assembly including an image bearing member and a device for forming a latent image on the image bearing member and an; accommodating device for accommodating a plurality of developing devices; the main assembly further including first developing device moving device for moving the developing devices; the accommodating device including second developing device moving device for moving the developing devices to a position at which the developing devices can be supplied into the main assembly and third developing device moving device for moving the developing devices from the supplying position into the main assembly; device for selecting a developing device for developing a latent image formed by the image forming device; device for starting image forming operation by the image forming device; and control device for controlling the first and second moving device, the control device operating the second moving device in response to a signal from the selecting device to place

Abstract: A developing device includes a developing agent holding vessel; and a developing roller having a rotating non-magnetic sleeve and a magnetic roller which is surrounded by the sleeve and has magnetic poles. A blade is disposed at an outlet of the vessel and a stirring roller stirs the developing agent which includes a toner and a carrier in the vessel. The developing roller is provided with a moving mechanism for shifting the position of the magnetic pole of the magnetic roller, wherein one of the magnetic poles is facing a surface of a photosensitive drum during normal use of the developing agent, and no magnetic pole faces the photosensitive surface during a replacement of the developing agent.

Abstract: A device for detecting the density of a two-component developer consisting essentially of a toner and a carrier for an electrophotographic copying machine and the like comprises a cylindrical magnet and a sleeve which covers it. They rotate inside a developing tank so that the developer will flow in a layer on the sleeve surface. A baffle plate is provided to control this flow and to form a small pool of the developer where its density can be effectively measured by a sensor. The bottom end of the baffle plate near the sleeve surface is immersed in the developer inside the tank so that the motion of the developer into and out of the pool formed in the vicinity of the sensor is smooth and stable.

Abstract: In an image formation apparatus for sequentially forming toner images on an image carrier and transferring the toner images onto a transfer material on a transfer material support member which is moved in an endless manner, when the transfer material is brought into contact with the image carrier other than in a transfer process, the surface of the image carrier is maintained at the same polarity as that of toner transferred to the transfer material. Thus, toner image transferred to the transfer material can be prevented from being offset onto the image carrier.

Abstract: An image forming apparatus includes a processor for processing image signals, an image forming system for forming images on recording mediums in accordance with the image signals processed by the processor, the image forming system being capable of forming the images in different colors, a detector for detecting an ambient condition, and a controller for controlling an image forming condition, relating to an image density, of the image forming system in accordance with an output of the detector and a color of image formation by the image forming system.

Abstract: An electrographic development apparatus has a sump for receiving developer material including carrier particles and toner particles. A magnetic brush receives development material from the sump and moves the material into a position relative to an electrostatic image carried on an insulating surface so that toner particles can be transferred to the electrostatic image to develop such image. A ribbon blender in the sump mixes the toner and carrier particles of the developer material, circulates developer material axially within the sump, agitates and shears the developer material, promotes tribocharging, and feeds developer out of the sump along a path leading to the magnetic brush.

Abstract: A copying machine including a light exposure device having a stationary light source for illuminating an original to be copied and adapted to form an electrostatic latent image on a photo-sensitive member through exposure by said light exposure device. A copying machine provided with a first insertion port and a transfer means adapted to feed an original to be copied from the first insertion port to the discharge position through the light exposure position so as to transfer an original to be copied, a second insertion port for inserting an original to be copied from the direction different from the first insertion port and a second transfer means adapted to reverse the feeding direction and the surface of the original to be copied from said second insertion port and feed the same to the exposure position.

Abstract: An image forming apparatus has a first image forming unit for image reproduction from an original image and a second image forming unit for image reproduction from image signals for achieving easier interruption imaging and complicated image processing. Four modes are selectable, a normal mode, an analog mode, a digital mode and an overlay mode. An image forming apparatus is provided wherein an original image is converted into an electrostatic charge which is maintained. A first electrostatic latent image is formed on a recording medium according to the maintained charge. A second electrostatic latent image is formed on the recording medium according to an input image signal. In response to a demand for the second latent image, formation of the first latent image is interrupted and restarted after formation of the second latent image.

Abstract: A programmed control device capable of connecting an external memory including a program to be used as a substitute of a main program of the device. The control device and the external memory to be connected thereto have the same data, respectively, to confirm the connection of adequate external memory.

Abstract: The saturation voltage of a photoconductor used in a discharged area development (DAD) reproduction device is used to control and maintain the voltage vectors that are associated with (1) the photoconductor's fully charged background area, (2) the development electrode voltage at the reproduction device's developer station, (3) the photoconductor voltage in areas that are occupied by image characters having a small surface area, and (4) the photoconductor voltage in a test patch area that is associated with a toner concentration control network having a toner patch sensor. These electrstatic parameters are periodically adjusted, to compensate for changes in the operating characteristics of the photoconductor and the imaging station.

Abstract: A disclosed solid state image pick-up element is constructed by a lateral static induction transistor in which source and drain regions thereof are arranged in a surface of a semiconductor layer formed on a substrate and a gate region for storing a light charge completely surrounds at least one of the source region and the drain region, whereby a source-drain current flows in parallel with the surface of the semiconductor layer. Moreover, a disclosed solid state image sensor utilizing the solid state image pick-up element mentioned above further includes a biasing means for inversely biasing the source and drain regions during a light signal storing period.