Abstract: An image forming apparatus includes an image forming device for forming an image onto a recording material and a fixing device for fixing the image on the recording material. The fixing device has a rotating member for conveying the recording material, and a controller for controlling the factors related to the peripheral speeds of the rotating member in accordance with the information of the peripheral speeds thereof and the size of the recording material. With the structure thus arranged, it is possible to prevent image problems from taking place due to the difference in the sheet conveying speeds between the image transfer and fixation operations.

Abstract: The present invention provides an image forming apparatus having an image bearing member for bearing a toner image, and a transfer rotary member for forming a nip between the transfer rotary member and the image bearing member, the transfer rotary member being provided at its surface with a solid layer and serving to transfer the toner image from the image bearing member onto a transfer material at the nip, and wherein a moving speed of a surface of the transfer rotary member at the nip is greater than a moving speed of a surface of the image bearing member at the nip, and a surface friction force of the transfer rotary member is greater than a surface friction force of the image bearing member by 3 to 20 times.

Abstract: An image heating device includes a heater generating heat upon electric power supply, and a film whose one surface slidably contacts the heater, and whose other surface moves together with a recording material bearing an image while contacting the recording material. The image on the recording material is heated by heat from the heater through the film. The device also includes a thermoprotector having a bimetal which mechanically changes in order to disconnect electric power supply to the heater when there is an excessive temperature rise. The bimetal of the thermoprotector contacts the heater.

Abstract: A fixing apparatus prevents the offset of toner onto a fixing roller, by forming a surface mold release layer made of pure fluororesin material on a core member of the fixing roller and by applying a bias voltage to the fixing roller.

Abstract: An image forming apparatus has an image forming unit for forming an image on a recording material, a fixing device for fixing the image on the recording material, an overlap-feed detector such as a transfer current detector for detecting an overlap-feed of the recording material conveyed to the fixing device and a set temperature controller for controlling the set temperature. The fixing device is maintained at a set temperature during an image fixing operation. The controller lowers the set temperature or stops the conveyance of the recording material when the overlap-feed detector detects the overlap feed. Accordingly, the image forming apparatus can prevent a fixing device from breaking due to an overlap-feed of a recording material.

Abstract: In a fixing device used in an image forming apparatus, temperature changes in a heating member are reduced by gradually reducing a power supply duty ratio while the heating member is subjected to temperature control aiming at a set temperature.

Abstract: An image forming system for forming an image on a recording sheet, including a rotatable image bearing member, a cleaning member contacting the image bearing member to remove toner remaining on the image bearing member, and charger means contacting the image bearing member and disposed at a downstream side of the cleaning member in a direction of movement of the image bearing member. Lubricant having a low resistance is painted on a contacting portion of the cleaning member between the image bearing member and the cleaning member.

Abstract: A developing apparatus includes a developer carrying member for carrying developer, an elastic blade press-contacted to the developer carrying member to regulate a layer of developer formed on the developer carrying member, where the elastic blade comprises an electrically conductive layer, and a high resistance layer located at the developer carrying member side of the conductive layer, and an electric field generating device for forming an oscillating electric field between the developer carrying member and the conductive layer, wherein a maximum intensity of the electric field is not less than 10.sup.6 V/m.

Abstract: An image forming system for forming an image on a recording sheet, including a rotatable image bearing member, a cleaning member contacting the image bearing member to remove toner remaining on the image bearing member, and charger means contacting the image bearing member and disposed at a downstream side of the cleaning member in a direction of movement of the image bearing member. Lubricant having a low resistance is painted on a contacting portion of the cleaning member between the image bearing member and the cleaning member.

Abstract: A developing apparatus for developing an electrostatic latent image having a movable developer carrying member for carrying one component developer to a developing zone where the developer carrying member is opposed to a latent image bearing member for carrying the electrostatic latent image, the developer carrying member being effective to triboelectrically charge the developer to a polarity for developing the latent image; a regulating member for regulating a thickness of a layer of the developer to be carried to the developing zone; a voltage source for applying a developing bias voltage to the developer carrying member; wherein the developer carrying member has a base member having a surface sandblasted to have an average surface roughness of 1.0-3.0 microns, and an outer layer thereon in which fine graphite particles are dispersed in a binder resin material, and wherein the outer layer has an average surface roughness of 0.8-2.5 microns.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming a toner image on the image bearing member; an image transfer device for transferring the toner image onto a transfer material at a transfer position, the transfer device including a rotatable member contactable to such a side of the transfer material as is opposite from a side contactable to the image bearing member and an electric field forming device for forming an electric field between the image bearing member and the rotatable member; wherein the electric field forming device forms a first electric field effective to transfer the toner from the rotatable member to the image bearing member and a second electric field which is opposite in a direction from the first electric field during a period in which the transfer material is absent at the transfer position, wherein each of the first and second electric fields is formed at least for a period required for the entire surface of the rotatable member pass

Abstract: A charging device including a movable member to be charged, and a charging member which is contactable to the member to be charged so as to charge the member to be charged, wherein the coefficient of dynamic friction between the member to be charged and a surface of the charging member contactable to the member to be charged is not lower than 0.4.

Abstract: A developing apparatus having a container for containing a one component developer, and a rotatable developing roller disposed facing an image bearing member to carry developer from the container to a development zone where it is supplied to an electrostatic latent image carried on an image bearing member. The developing roller includes a metal base member and a resin coating layer thereon in which fine conductive particles are dispersed. The developing roller has a surface including an end region adjacent an end of the roller, and an intermediate region. In the end region, the base member is not roughened and the resin layer is not provided. In the intermediate region, inside the end region, the base member is roughened and is coated with the resin layer. A sealing member is provided for preventing leakage of the developer from the container at the end of the developing roller, the sealing member being faced to the end region of the developing roller.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming a toner image on the image bearing member; image transfer device for transferring the toner image from the image bearing member to a transfer material at an image transfer station, wherein the transfer device includes a charging member press-contacted or faced to the image bearing member and a device for applying a voltage to the charging member, wherein the voltage applying device applies a voltage to the charging member so that the charging member is constant-voltage-controlled when an image region of the image bearing member is in the transfer station, and the charging member is constant-current-controlled during at least a part of a period when it is not in the transfer station, wherein a voltage V2 applied during the constant voltage control is a voltage V1 appearing in the transfer device during the constant current control multiplied by a coefficient R, in which R is larger than 1.

Abstract: An image fixing apparatus for fixing a toner image on a recording material includes a pair of rotatable members for forming a nip through which the recording material is passed; and bias voltage applying source for applying a bias voltage to at least one of the rotatable members, wherein the bias voltage is automatically changed in accordance with change of an ambient condition.

Abstract: A developing apparatus for developping an electrostatic latent image includes a movable developer carrying member facing toward or contacted with an image bearing member in a developing zone. An elastic regulating member for forming a regulated developer layer on the developer carrying member is elastically urged toward the developer to form a nip therebetween, through which the developer is conveyed to the developing zone. Fine particles different from particles constituting the developer are arranged on the surface of the regulating member comprising the nip.

Abstract: An image forming apparatus has a charging device for charging a photosensitive member containing an organic photoconducter, an exposure device, a developing device including a developer, a transfer device and a cleaning device. The photosensitive member employs an organic photoconductor and a polycarbonate resin layer which forms the surface of the photosensitive member. The developer device has a sleeve with a thin layer of an electrical coating material containing dispersed carbon particles. The developer contains insulating magnetic toner particles of relatively small particle size formed from a styrene-acrylic type copolymer or a polyester resin and a magnetic powder.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming an image on the image bearing member; and a transfer device for transferring the image from the image bearing member onto a transfer material, the transfer device including a movable transfer member contacted to the image bearing member and for conveying the transfer material by the contact portion. The transfer member is disposed in such a direction that a surface friction in the direction of the movement of the transfer member relative to the image bearing member is large.

Abstract: An electrophotographic process wherein line width is controlled by examining stroke widths of data contained in output information, type of font and other criteria. The control of the electrophotographic process includes control of conditions of electrostatic charge on the dram, exposure or development of a photosensitive body. The electrophotographic process may be controlled in accordance with the font supplied to a printer.