Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.

Abstract: Heat-equalizing rotation of a fixing member and a pressing member for equalizing the distribution of the temperature of a surface of the fixing member in a width direction is performed after a recording medium having a size less than or equal to a predetermined size in the width direction passes a nip portion and before a recording medium having a size greater than the predetermined size in the width direction passes the nip portion. Further, a termination condition of the heat-equalizing rotation is selected from among a plurality of different kinds of termination conditions, based on image formation related information related to next image formation performed after the heat-equalizing rotation.

Abstract: A fixing device capable of shifting to a sleep state includes a heat source; a rotatable fixing member that is partly heated by the heat source to heat an unfixed image carrying surface of a recording medium; a rotatable pressing member that is in pressure contact with the fixing member to form a nip portion between the pressing member and the fixing member; a rotation drive unit that directly or indirectly rotates the fixing member; a temperature detecting unit that detects a temperature of the fixing member; and a controller configured to prohibit the fixing device from shifting to the sleep state when the temperature of the fixing member in a region facing the heat source is equal to or more than a predetermined temperature T1 at a point when a predetermined time period t1 has elapsed from the stop of rotation drive of the rotation drive unit.

Abstract: A fixing device includes a controller connected to a heater and at least one of a pressing rotary body and an endless rotary body. The controller performs a first fixing operation, a first transition operation, a second fixing operation, and a second transition operation. The first fixing operation fixes a toner image on a first recording medium after the fixing device is powered on. The first transition operation rotates the pressing rotary body and the endless rotary body while controlling the heater to maintain the endless rotary body at a predetermined temperature for a first duration time. The second fixing operation fixes a toner image on a second recording medium. The second transition operation rotates the pressing rotary body and the endless rotary body while controlling the heater to maintain the endless rotary body at the predetermined temperature for a second duration time smaller than the first duration time.

Abstract: When calculating an actual turn-on duty based on a required duty according to a feedback control, the actual turn-on duty is corrected using a correction table or a correction conversion formula such that a required turn-on duty and the actual turn-on duty coincide with each other. A fixing heater is controlled according to the corrected actual turn-on duty.

Abstract: An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.

Abstract: A fixing device includes a heating device to heat an endless rotary body with radiant heat, a power source to supply power to the heating device, a first heat source to heat a region on the endless rotary body corresponding to a width of the small size sheet, and a second heat source to heat regions on the endless rotary body corresponding to both widthwise ends of the large size sheet outside the width of the small size sheet. The power source supplies power only to the first heat source when the small size sheet is printed and to both the first and second heat sources when the large size sheet is printed. The power source supplies more power to the first heat source when the small size sheet is printed than when the large size sheet is printed within a maximum power available to the fixing device.

Abstract: An image forming apparatus includes a fixing unit and a fixing process managing system. The fixing process managing system, including a mode switchover unit, controls a time mode and a temperature mode for heating a fixing member. In the time mode, the fixing unit is determined to be ready for a fixing process when a given time elapses after activation of the image forming apparatus. In the temperature mode, the fixing unit is determined to be ready for a fixing process when a temperature of the fixing member attains a given reference temperature after activation of the image forming apparatus. The mode switchover unit selects between the temperature mode and the time mode. The fixing process managing system selects the temperature mode instead of the time mode when a supply amount of electrical power to the fixing unit is determined to be below a required electrical power supply level.

Abstract: An image forming apparatus includes an image forming part, a fixer including a heating member and a pressure member, a reverse transport part to forward a recording medium transported from the fixer to the image forming part, a toner image sensor to detect presence of a toner image on the recording medium, and a controller. When a glossy image formation mode is selected and no toner image is detected on the recording medium, the image forming part does not form a toner image on the recording medium, the fixer performs a first heating and pressing process and transports the recording medium to the reverse transport part, the reverse transport part transports the recording medium to the image forming part, the image forming part forms a toner image on the recording medium transported from the reverse transport part, and the fixer performs a second heating and pressing process and fixes the toner image thereon.

Abstract: An image forming apparatus includes a fixing unit and a fixing process managing system. The fixing process managing system, including a mode switchover unit, controls a time mode and a temperature mode for heating a fixing member. In the time mode, the fixing unit is determined to be ready for a fixing process when a given time elapses after activation of the image forming apparatus. In the temperature mode, the fixing unit is determined to be ready for a fixing process when a temperature of the fixing member attains a given reference temperature after activation of the image forming apparatus. The mode switchover unit selects between the temperature mode and the time mode. The fixing process managing system selects the temperature mode instead of the time mode when a supply amount of electrical power to the fixing unit is determined to be below a required electrical power supply level.

Abstract: An image forming device whereby stable fixing performance is obtained and whose fixing properties are excellent and that does not produce curling of the paper after fixing, due to performing control for correcting fixing temperature by environmental sensing not only during standby but also over time. A plurality of temperature detecting units are provided in the fixing device and a plurality of detecting units that detect temperature and humidity are provided within the image forming device. Temperature correction is performed whereby the target control temperature of the fixing device is changed to a prescribed value in accordance with the temperature or humidity detected by the plurality of detecting units.

Abstract: An image forming apparatus includes an image forming mechanism and a fixing mechanism. The fixing mechanism fixes a visible image formed by the image forming mechanism onto a recording sheet. The fixing mechanism includes a first roller, a second roller, a belt, a third roller, and an applicator. The second roller includes a first heater having a first heat capacity. The belt is looped over the first and second rollers. The third roller is arranged opposite to the first roller via the belt, includes a second heater having a heat capacity smaller than the first heat capacity of the first heater, applies a pressure to the belt and the first roller, and rotates in conjunction with a movement of the first roller via the belt. The applicator is arranged at a position in contact with the third roller and applies oil to a surface of the third roller.

Abstract: An image forming apparatus includes an image forming part, a fixer including a heating member and a pressure member, a reverse transport part to forward a recording medium transported from the fixer to the image forming part, a toner image sensor to detect presence of a toner image on the recording medium, and a controller. When a glossy image formation mode is selected and no toner image is detected on the recording medium, the image forming part does not form a toner image on the recording medium, the fixer performs a first heating and pressing process and transports the recording medium to the reverse transport part, the reverse transport part transports the recording medium to the image forming part, the image forming part forms a toner image on the recording medium transported from the reverse transport part, and the fixer performs a second heating and pressing process and fixes the toner image thereon.

Abstract: An image forming apparatus may include an image reading area reading an original image and preparing image information thereof, an image forming area forming an image on a sheet-shaped recording medium based on the image information, and a discharging area located therebetween, at least opening in front and including an outlet discharging the sheet-shaped recording medium with a space connected thereto, wherein at least the discharging area further includes at least an inhibitor inhibiting an object blocking discharge of the sheet-shaped recording medium from approaching the outlet through the space.

Abstract: An image forming device whereby stable fixing performance is obtained and whose fixing properties are excellent and that does not produce curling of the paper after fixing, due to performing control for correcting fixing temperature by environmental sensing not only during standby but also over time. A plurality of temperature detecting units are provided in the fixing device and a plurality of detecting units that detect temperature and humidity are provided within the image forming device. Temperature correction is performed whereby the target control temperature of the fixing device is changed to a prescribed value in accordance with the temperature or humidity detected by the plurality of detecting units.

Abstract: An image forming apparatus includes an image forming mechanism and a fixing mechanism. The fixing mechanism fixes a visible image formed by the image forming mechanism onto a recording sheet. The fixing mechanism includes a first roller, a second roller, a belt, a third roller, and an applicator. The second roller includes a first heater having a first heat capacity. The belt is looped over the first and second rollers. The third roller is arranged opposite to the first roller via the belt, includes a second heater having a heat capacity smaller than the first heat capacity of the first heater, applies a pressure to the belt and the first roller, and rotates in conjunction with a movement of the first roller via the belt. The applicator is arranged at a position in contact with the third roller and applies oil to a surface of the third roller.

Abstract: A two-component developer including toner and magnetic carriers is provided. The two-component developer is characterized in that when a development device including a developer bearing member bearing the two-component developer is operated under a development condition of an image forming apparatus using a quasi-photoconductor in which a 10 ?m thick layer of tetrafluoroethylene resin is provided to a conductive material, the number of times of light emission occurring in a magnetic brush formed on the developer bearing member due to partial conduction in the magnetic brush is 10 times or less per second at an observation cross section that is perpendicular relative to a rotation axis of the developer bearing member.

Abstract: A two-component developer including toner and magnetic carriers is provided. The two-component developer is characterized in that when a development device including a developer bearing member bearing the two-component developer is operated under a development condition of an image forming apparatus using a quasi-photoconductor in which a 10 &mgr;m thick layer of tetrafluoroethylene resin is provided to a conductive material, the number of times of light emission occurring in a magnetic brush formed on the developer bearing member due to partial conduction in the magnetic brush is 10 times or less per second at an observation cross section that is perpendicular relative to a rotation axis of the developer bearing member.

Abstract: An image forming apparatus of the present invention includes a latent image forming device for forming a latent image on an image carrier and a developing device for developing the latent image with toner to thereby form a corresponding toner image. The surface of an intermediate image transfer body is movable and includes an high-resistance layer having a volume resistivity of 1010 &OHgr;·cm or above. A primary image transferring device transfers the toner image from the image carrier to the intermediate image transfer body. Secondary image transferring device transfers the toner image from the intermediate image transfer body to a sheet. A polarization uniforming device uniforms, at the beginning of an image forming operation, polarization left in the high-resistance layer while preserving the polarity of the polarization after the surface of the intermediate image transfer body has started moving, but before the toner image is transferred from the image carrier to the secondary image transfer body.

Abstract: An image forming apparatus of the present invention includes an image carrier. A rotary developing device adjoins the image carrier and includes a plurality of developing sections for developing a latent image formed on the image carrier with a magnetic developer. A toner cartridge unit includes a plurality of toner cartridges and is rotatable integrally with the developing device. A plurality of toner conveying device each connect one toner cartridge to the associated developing section and each include a toner passage and a toner conveying member disposed in the toner passage. A magnet adjoins a toner outlet, which is formed in the toner passage and communicated to the developing section, for forming a magnetic field that traverses the toner passage over the entire diameter of the toner passage. Toner stored in each toner cartridge is prevented from unexpectedly flowing into the associated developing section when replenishment is not effected.