Abstract: An image forming system, having means for storing usage histories of latent image carriers, developer, or the like and maintenance cycles of image forming apparatuses and having a function for selecting image forming apparatuses outputting an image based on the usage history data or the maintenance cycles, in order to achieve uniform output image qualities. By managing the usage histories so as to achieve approximately the same deteriorated conditions of the latent image carriers of the image forming apparatuses, the image forming apparatuses can be put in the same condition and thus the output image qualities can be approximately the same in the image forming apparatuses. Additionally, the maintenance cycles can be adjusted to be approximately the same in the image forming apparatuses. Otherwise, maintenance periods can be controlled so as not to overlap in the image forming apparatuses.

Abstract: This invention relates to an image forming apparatus which employs a recycling scheme of recovering and reusing transfer residue toner, and a convey control method for recycle toner. In order to prevent a phenomenon such as fogging or character thickening, a toner recycle mechanism shares one driving source with a photosensitive body or fixing unit, and includes an electromagnetic clutch for switching driving force transmission to the recycling means when driving the photosensitive body or fixing unit, and a controller which controls power supply to the electromagnetic clutch. The convey control method for recycle toner includes the steps of starting copying, measuring a printing ratio of an image pattern per image, and suppressing a return amount of the recycle toner when the printing ratio of the image pattern is low.

Abstract: In a fixing apparatus for fixing a toner image on a transfer material by applying heat and pressure to the transfer material, the fixing apparatus includes: a roll-shaped rotary member for applying heat, including a ray radiating device for radiating a ray generated by a ray generating source provided inside the ray radiating device; a cylindrical ray-transmitting base member through which the ray generated by the ray generating source is transmitted, being arranged around the ray radiating device; a resilient layer; and a ray absorbing layer provided outside the resilient layer for absorbing the ray generated by the ray generating source. The following condition is satisfied, K1>K2 where K1 (J/cm·s·K) represents thermal conductivity of the ray-transmitting base member and K2 (J/cm·s·K) represents thermal conductivity of the resilient layer.

Abstract: A fixing apparatus for fixing a toner image on a transfer sheet with heat and pressure is provided with (A) a heating roller including a cylindrical light transmitting base member; a heat ray generating device, provided inside of the cylindrical light transmitting base member, to generate a heat ray; a heat ray transmitting elastic layer generate a heat ray; a heat ray transmitting elastic layer provided on an outer surface of the cylindrical light transmitting base member and including a rubber layer; and a heat ray absorbing layer, provided on the outer surface of the cylindrical light transmitting base member, to absorb the heat ray passing through both of the cylindrical light transmitting base member and the heat ray transmitting elastic layer, and (B) a pressing roller provided to come in contact with the heating roller so that the transfer sheet is nipped with a nip width between the heating roller and the pressing roller.

Abstract: In a fixing apparatus for fixing toner images on a transfer material upon which toner images have been placed by applying heat to the transfer material, the fixing apparatus includes: a roll-shaped rotary member for applying heat to the transfer material upon which toner images have been placed, the roll-shaped rotary member including a cylindrical ray-transmitting base member, and a ray absorbing layer for generating heat onto the transfer material upon which toner images have been placed so as to fix the toner on the transfer material, the ray absorbing layer, provided on an outer side of the ray-transmitting base member; a ray irradiating device for irradiating ray to the ray absorbing layer, the ray irradiating device provided inside the cylindrical ray-transmitting base member; bearing member for rotatably supporting the roll-shaped rotary member; flange members provided on both ends of the ray-transmitting base member; and an elastic covering member provided between the flange member and the roll-shaped

Abstract: A fixing apparatus that fixes, on a transfer material, toner images on the transfer material through heating and pressing, wherein, a ray-radiating member that radiates rays is provided, and a roll-shaped rotary member for applying heat is formed by providing a cylindrical ray-transmitting base member which can transmit the rays and a cylindrical ray-transmitting elastic layer or a ray-transmitting heat insulating layer which can transmit the rays, and by providing, on the outer side of the ray-transmitting elastic layer or the ray-transmitting heat insulating layer, a ray absorbing layer that absorbs the rays stated above. The inequality of T1<T2<T3 holds when T1 (°) represents an average temperature in the layer of the ray-transmitting base member, T2 (°) represents an average temperature in the layer of the ray-transmitting elastic layer or the ray-transmitting heat insulating layer, and T3 (°) represents an average temperature in the layer of the ray absorbing layer during a warm-up.

Abstract: A fixing apparatus for fixing toner images on a transfer material by applying heat on the transfer material, the fixing apparatus includes: a roll-shaped rotary member for applying heat, including a cylindrical ray-transmitting base member, and a ray absorbing layer for generating heat, provided on an outer side of the ray-transmitting base member; a ray irradiating device for irradiating ray, provided inside the cylindrical ray-transmitting base member; and flange members provided on both ends of the ray-transmitting base member, and each of the flange members being joined with the ray-transmitting base member through a joining elastic layer.

Abstract: A color image forming apparatus includes a photoreceptor drum having an outer diameter of 50 mm to 100 mm and a rotational axis, four charging devices for charging the photoreceptor drum, and four exposure devices, provided inside the photoreceptor drum, for imagewise exposing an inner surface of the photoreceptor drum to form respective four latent images. Four developing devices are provided outside the photoreceptor drum at an upper section thereof for developing respective ones of the four latent images using respective different one-component type color developers to form four different color toner images in a superimposed manner on an outer surface of the photoreceptor drum during one rotation thereof the photoreceptor drum.

Abstract: A color image forming method, including the steps of: charging a front surface of a photoreceptor; conducting image wise exposure onto the charged front surface from a rear surface of the photoreceptor so that a latent image is formed on the front surface; developing the latent image with a color toner so that a color toner image is formed on the front surface; and repeating the steps of charging, conducting image wise exposure and developing so that a multicolor toner image is formed on the front surface; in which a secondary color of the multicolor toner image, which consists of two color toner images, is formed in a manner that the two color toner images are formed by conducting the image wise exposure at a same exposure amount; and the first one of the two color toner images is formed by conducting the image wise exposure at an exposure amount which creates a potential smaller than that of already formed primary color of the multicolor toner image, which consists of single color toner image.

Abstract: In a color image forming apparatus provided with a photoreceptor having a rotatable peripheral surface; plural sets of a charging device, an imagewise exposure device, and a developing device, each set of the plural sets is provided separately from other sets around the peripheral surface of the photoreceptor so that plural color component images are formed one after another by the plural sets and are superimposed so as to form a color image on the peripheral surface during a single rotation of the peripheral surface. The developing device has a casing and the imagewise exposure device and the developing device of each set are arranged such that a portion on the peripheral surface locating at an imagewise exposing position moves into the casing of the developing device before the electric potential V1 of the portion is lowered to the half of V1 (V1/2).

Abstract: An image forming apparatus comprises a photoreceptor drum, a supporting member provided inside the photoreceptor drum and supporting plural exposure devices; and a signal passage to transmit an image signal to the plural exposure devices. The signal passage connects the outside and the inside of the photoreceptor drum by passing a part of the supporting member.

Abstract: An image forming apparatus has an image forming body which is rotatable in a subsidiary scanning direction. A plurality of imagewise exposure devices for imagewise exposing the image forming body are arranged to face the image forming body and to be aligned in a straight line in a primary scanning direction perpendicular to the subsidiary scanning direction of the image forming body. A common supporting member is provided for supporting the plurality of exposure devices, and bearing members are provided on first and second ends of the common supporting member. The plurality of exposure devices are: (i) radially arranged on the common supporting member with respect to a rotation axis of the image forming body, and (ii) fixed on the supporting member with respect to the bearing members, and the image forming body is rotatable against the common supporting member through the bearing members.

Abstract: An image forming apparatus having an exposure optical system provided with an exposure light source in which light-emitting elements are arranged on a base plate to be line-shaped and with a lens array of a distributed refractive index type that converges a beam emitted from the exposure light source on the surface of a photoreceptor and conducts imagewise exposure. The apparatus is configured to satisfy the expression: ##EQU1## In the expression, .DELTA.T1 represents a variation width (K) of the temperature in the vicinity of light-emitting elements, R represents a radius of the photoreceptor mentioned above, Ri represents a length (.mu.m) of each member constituting the exposure optical system in the radial direction of the photoreceptor, .alpha. represents a coefficient of linear thermal expansion (.degree.C..sup.-1) of a transparent base that forms the photoreceptor, .alpha.i represents a coefficient of linear thermal expansion (.degree.C..sup.

Abstract: A method of producing a substrate for a photoreceptor having an exposing device therein for use in an electrophotographic apparatus, including the steps of: injecting polymerizable liquid material into a die whose inner surface is cylindrical; polymerizing the polymerizable liquid material while rotating and heating the die so that a substrate is formed inside the die; and removing the substrate from the die after the polymerizing, wherein the polymerizable liquid material is a transparent resin material and a thickness of the substrate is controlled according to an injecting amount of the polymerizable liquid material.

Abstract: A color image forming apparatus including: an image forming body rotating about a rotary axis; a plurality of imagewise exposure devices mounted on an optical system supporting body and provided inside the image forming body for imagewise exposing the image forming body, wherein the image forming body is integrally formed with the optical system supporting body; a plurality of developing units provided around the image forming body; a suspending member for suspending the optical system supporting body; and guiding member for guiding the suspending member so that the image forming body is pulled out in a direction of the rotary axis of the image forming body.

Abstract: In a color image forming apparatus, wherein plural toner images are superimposed on the photoreceptor during a single rotation of the photoreceptor by a plurality of charging devices, image exposing means and developing means, each of the plurality of image exposing means comprises an array-shaped plural elements aligned in the axial direction of the photoreceptor and the color image forming apparatus further comprises heating means or heat absorbing means provided for each of the plurality of image exposing means and control means for controlling a temperature of each of the plurality of image exposing means independently of others by the heating means or the heat absorbing means.

Abstract: An image forming apparatus includes a rotary image forming body; a charger provided around the image forming body for charging the image forming body; a plurality of imagewise exposure devices for imagewise exposing the charged image forming body to form respective latent images thereon; and a plurality of developing devices for developing the respective latent images formed on the image forming body to form respective toner images. A plurality of different color toner images thus formed by the respective chargers, the respective imagewise exposure devices and the respective developing devices are superimposed on the image forming body, thereby a color toner image is formed. The image forming apparatus further includes a transfer device for transferring the color toner image on the image forming body onto a transfer member; a cleaning device for removing a residual toner on the image forming body; a support member for supporting the plurality of exposure devices.

Abstract: An optical system assembling method in an image forming apparatus in which there are provided an image forming body around which a plurality of exposure device each having a linear exposure optical system to imagewise expose on the image forming body, and a plurality of developing device containing respective color toners different from each other which are superimposed on the image forming body to form a color toner image, the method further having the steps of: lighting the exposure optical system; forming an image emitted from the exposure optical system on a sensor which is disposed at a position corresponding to a photosensitive surface of the image forming body with respect to the exposure optical system; adjusting a position of the exposure optical system on the basis of a result of the image forming so that a focal point of the exposure optical system is coincident with a surface of the sensor; and fixing at the adjusted position the exposure optical system to an optical system supporting body provide

Abstract: An image forming apparatus includes: a photoreceptor drum; a charger for charging an outer surface of the photoreceptor drum; image exposure devices each for exposing the photoreceptor drum to form a latent image thereon, wherein the image exposure devices are provided inside the photoreceptor drum, and are detachably mountable with the photoreceptor drum to the image forming apparatus; a developing device for developing the latent image to form a toner image on the outer surface of the photoreceptor drum; and a supporting member on which the image exposure devices are mounted, wherein the supporting member and the photoreceptor drum are connected through bearing members on both ends of the photoreceptor drum, and the supporting member has an engaging portion for engaging with a part of the image forming apparatus to fix the image exposure devices through the supporting member, while the photoreceptor drum is rotated around the image exposure devices through the bearing members.

Abstract: A color image forming apparatus includes a drum type image forming body; four charging devices for charging the image forming body; four exposure devices fixed on the main body for imagewise exposing the charged image and forming body to form a latent image; four developing devices each for developing the latent image to form a different colored toner image. After operations by the charging devices, the exposure devices and the developing devices are repeated to superimpose the different colored toner images on the image forming body, the superimposed colored toner images are transferred by a transfer device including an intermediate transferring member and a transfer member in contact with the intermediate transferring member onto a recording material at one time.