Abstract: An image forming apparatus including a plurality of image forming cartridges removably mounted to an apparatus body one above the other is disclosed. Structural members each partition off a space between nearby image forming cartridges mounted to the apparatus body. The apparatus is capable of obviating banding ascribable to the vibration of the cartridges.

Abstract: An electrophotographic apparatus, includes: an electrophotographic photosensitive member and a charging device. The charging device includes a conductor particle-carrying member having an electroconductive and elastic surface, and conductor particles having a particle size of 10 nm-10 &mgr;m and carried on the carrying member so as to be disposed in contact with the photosensitive member, thereby directly injecting charges to the photosensitive member to charge the photosensitive member. The photosensitive member includes a photosensitive layer and a charge injection layer as a surface layer disposed in this order on a support, the charge-injection layer having a thickness d (&mgr;m) and an elastic deformation percentage We (OCL) (%) satisfying a relationship of formula (1) below with an elastic deformation percentage We (CTL) (%) of the photosensitive layer: −0.71×d+We(CTL)≦We(OCL)≦0.03×d3−0.89×d2+8.43×d+We(CTL)  (1).

Abstract: A developing roller of the present invention is made up of a nonmagnetic sleeve and a magnet roller disposed in the sleeve. The magnet roller includes a cylindrical magnet produced by molding a mixture of magnetic powder and a high polymer, and a single rare-earth magnet block mounted on the magnet at a position corresponding to a main magnetic pole for development. The cylindrical magnet is magnetized such that magnetic poles adjoining the main magnetic pole are opposite in polarity to the main pole. The main pole and each pole adjoining it make an angle of 45° or less therebetween.

Abstract: A developing apparatus, an image formation apparatus and a process cartridge is provided. Even though the sealing materials of the initial developer container are stripped off in such a way that the process cartridge having the developing apparatus is tilted, the initial developer can be uniformly supplied along the central axis line of the developer carrier. The developing apparatus performs a self toner control and has an initial developer case 10 for containing the non-used initial developer 3c that is input into the developer containing space S. The initial developer case 10 is divided internally into a plurality of partition spaces 10b along the direction of the central axial line D of the developing sleeve 4, so that a plurality of partitions 10c is formed inside the initial developer case 10.

Abstract: A vacuum drum assembly for a printing machine has a drum with an array of passageways distributed along its length and around its periphery. The passageways permit air to flow from outside the drum to inside the drum in response to reduced air pressure inside the drum. The assembly also has an array of valve members, each valve member being movable between a closed position in which that valve member restricts at least one of the passageways and an open position in which the restriction of that passageway or those passageways is reduced. The assembly is arranged such that, when a partial area of the drum is wrapped with a sheet of material, at least some of the valves for the passageways adjacent the edges of that area are open, and the valves for the passageways which are not covered by the sheet and are not adjacent the edges of that area are closed.

Abstract: An image forming apparatus has a latent image carrier on which a latent image is formed. A developer carrier conveys a one-component non-magnetic developer and develops the latent image either in close proximity to or in contact with the latent image carrier. A voltage application unit applies an AC-superimposed bias voltage to the developer carrier. A regulating member abuts against the developer carrier to regulate the thickness of the developer layer on the developer carrier. The regulating member has a semiconductive member provided at the distal end thereof to produce an electric potential difference between the semiconductive member and the developer carrier, to which the AC-superimposed bias voltage is applied, when regulating the thickness of the developer layer on the developer carrier, thereby forming a line-shaped uneven conveying surface. Thus, the occurrence of banding and longitudinal unevenness and stripes is prevented, and fogging and scattering are also prevented.

Abstract: An object of the present invention is to provide an image heating apparatus that has heating device for heating an image formed on a recording material, the heating device including a moving member moving as coming into contact with the recording material, a temperature detecting element for detecting a temperature of the heating device, and power supply control device for controlling an electrical power to the heating device so that the temperature detected by the temperature detecting element is maintained at a set temperature, wherein the power supply control device sets the electrical power in accordance with the temperature detected by the temperature detecting element and a moving speed of the moving member.

Abstract: A laser control device includes a light amount varying section for varying the light exposure amount at plural levels is provided with a correction section for correcting the difference between the times to the peaks of laser outputs of print signals input to a laser control circuit. The turning on time of each print signal is corrected, whereby the difference between the times to the peaks of laser outputs of the print signals different in light exposure amount can be eliminated for correcting the difference between image print positions.

Abstract: Apparatus for developing a latent electrostatic image to a developed image with a developer, having a developer bearing member capable of carrying developer on a surface thereof, and a layer thickness regulating member for regulating developer carried on the developer bearing member to a uniform thickness, wherein at least the surface of the layer thickness regulating member is made of a material which includes at least one of a cross-linked alkylalkoxyl-group-containing nylon resin and a cyclic polyolefin.

Abstract: A fixation device for fixation of toner material on a printing stock for an electrophotographic printer with a radiation wavelength essentially in the ultraviolet range for thermal melting of the toner material, and the stock, as carrier of the toner material, is heatable by a device essentially during the exposure process.

Abstract: In an image forming apparatus, a color registration error correction computing portion calculates optimal typical value of position change quantity for each image forming region. Based on these typical values, write timing at each of write portions is controlled by an image control portion. That is, color registration error correction is executed based on optimal correction quantity for each image forming region.

Abstract: A cartridge is set in a printer main unit, and has a remaining toner measurer which measures toner in a toner chamber upon setting of the cartridge. A cartridge memory stores information of a remaining toner amount measured previously. CPU compares the remaining toner amount measured newly with the remaining toner amount measured previously and read from the cartridge memory. If there is an increase in the toner, the cartridge is determined as improper cartridge reloaded with the toner. An alarm signal is generated. Also, printing is inhibited. In another preferred embodiment, shortage information is assigned to the cartridge upon using up the toner. The cartridge, if it has the shortage information, is determined as improper. If a characteristic of the toner is not within a reference range, the cartridge is determined improper. In another preferred embodiment, an upper limit of the number of times of toner reloading is predetermined.

Abstract: A process cartridge toner supply arrangement used in a laser printer for controlling supply of toner is constructed to include a receiving member, the receiving member having toner receiving openings and a toner accommodating portion, a replaceable supplying member, the supplying member having a toner accommodating portion and toner supplying openings, and a blocking member provided between the receiving member and the supplying member and moved to close/open the toner passage between the toner receiving openings and the toner supplying openings.

Abstract: An image forming apparatus including an image carrier including a conductive support, at least a photoconductive layer formed on the conductive support, and a surface protection layer formed on the photoconductive layer and including a charge injection layer. Also included is a charge member for charging the image carrier in contact with the surface protection layer when applied with a voltage. Further, the surface protection layer has a diamond-like structure or an amorphous structure containing hydrogen with a volume resistance of 109 &OHgr;·cm to 1012 &OHgr;·cm and a Knoop hardness of 400 Kg/mm2 or greater, and the charging member includes magnetic particles for charging having a mean particle size ranging from 20 &mgr;m to 150 &mgr;m. Also, a light transmission of the surface protective layer is 50% or more of a wavelength of light used for exposing the image carrier.

Abstract: Disclosed is an image forming apparatus that enables to transversely move a sheet separator without a dedicated drive source and with a simplified construction to thereby reduce production cost of the apparatus. The image forming apparatus includes a thrust driving mechanism for reciprocating the sheet separator in an axial direction of a heater roller. The mechanism includes a worm gear which is rotated by a driving force of a drive source for rotating the heater roller, a helical gear which is meshed with the worm gear, and an eccentric cam which is mounted coaxially with an axis of rotation of the helical gear. A guide member for supporting the sheet separator is reciprocated in the axial direction of the heater roller in accordance with rotation of the eccentric cam.

Abstract: A sheet treating apparatus is mountable in a space portion of an image forming apparatus including an image-forming portion for forming an image on a sheet and an image-reading portion for reading an image of an original. The image-reading portion is disposed above the image-forming portion. The sheet is delivered in the space portion formed between the image-forming portion and the image-reading portion. The sheet treating apparatus includes a connection path unit to be connected with a sheet delivery path for delivering the sheet from the image-forming portion, which connection path unit is mounted in the space portion from the outside of a side surface of the main body of the image forming apparatus, and a sheet-treating unit for performing a treatment of the sheet transported from the connection path unit, which sheet-treating unit is mounted in the space portion from the front side of the main body of the image forming apparatus.

Abstract: A system for varying the amount of thermal energy transmitted to print media in a printing device having a fuser with a pressure roller and a heated drive roller biased against the pressure roller includes a first idler roller, having a location which is variable relative to a print path of print media traveling through the printing device, and a thermally conductive belt, disposed around the drive roller and the first idler roller. Thermal energy transferred to the print media traveling along the print path is varied by changing the location of the first idler roller relative to the print path.

Abstract: A main body of an image forming apparatus has an image forming section to which a sheet is fed from an optional sheet deck when it is coupled to the main body. The sheet fed from the sheet feeding device is received and then forwarded to the image forming section by a sheet conveyor unit which is demountably provided in the main body of the image forming apparatus and is formed of a frame, a pair of conveying rollers within the frame, and a guide.

Abstract: Disclosed is a fixing apparatus, in which a cylindrical roller comprising a thin metal layer having a small heat capacity is heated by an induction heating and, when the toner image transferred onto a paper sheet is fixed to the paper sheet, it is possible to control accurately the temperature on the surface of the cylindrical roller. Where the toner image formation on the paper sheet having a width smaller than the length of the cylindrical roller and the fixing operation of the toner image are carried out repeatedly, it is possible to prevent the temperature elevation in the edge portion of the roller. In addition, the power consumption can be saved.

Abstract: An image forming apparatus includes an image bearing member, a charging member, disposed so as to be contactable with the image bearing member, for charging the image bearing member with a peripheral velocity difference between the charging member and the image bearing member, and a controller for variably controlling the peripheral velocity difference at the time when an area which becomes an image forming area of the image bearing member is charged by the charge member.