Abstract: An image forming apparatus includes: an image supporter that supports an image to be transferred to paper; a transfer belt that is opposed to the image supporter and forms a nip; and a first heater and a second heater that heat the transfer belt, wherein, the first heater has higher performance to uniformly heat an entire area of the transfer belt than the second heater; and the second heater has higher performance to respond to a temperature change of the transfer belt in a case of output change than the first heater.

Abstract: An image forming apparatus includes: an image supporter that supports an image to be transferred to paper; a transfer belt that is opposed to the image supporter and forms a nip; and a first heater and a second heater that heat the transfer belt, wherein, the first heater has higher performance to uniformly heat an entire area of the transfer belt than the second heater; and the second heater has higher performance to respond to a temperature change of the transfer belt in a case of output change than the first heater.

Abstract: An image forming apparatus includes: a rotatable image bearing member; a transferring member that forms a transfer nip portion with the image bearing member; a voltage application section that applies a voltage to the transferring member in such a manner that a certain amount of current flows through the transferring member; and a control section that sets a front-end current to a current that flows through the transferring member when a voltage having a polarity opposite to a transfer polarity and an absolute value substantially the same as or greater than an absolute value of a surface potential of the image bearing member is applied to the transferring member, the control section controlling the voltage application section in such a manner that the set front-end current flows through the transferring member when a front-end portion of a recording sheet in a conveyance direction passes through the transfer nip portion.

Abstract: An image forming apparatus includes: a rotatable image bearing member; a transferring member that forms a transfer nip portion with the image bearing member; a voltage application section that applies a voltage to the transferring member in such a manner that a certain amount of current flows through the transferring member; and a control section that sets a front-end current to a current that flows through the transferring member when a voltage having a polarity opposite to a transfer polarity and an absolute value substantially the same as or greater than an absolute value of a surface potential of the image bearing member is applied to the transferring member, the control section controlling the voltage application section in such a manner that the set front-end current flows through the transferring member when a front-end portion of a recording sheet in a conveyance direction passes through the transfer nip portion.

Abstract: An image forming apparatus including a primary transfer unit to transfer toner images of plural colors on image carriers onto an intermediate transfer member; a secondary transfer unit to transfer the toner images onto a transfer material; and a pre-secondary transfer discharge unit to discharge charges of the toner images, wherein the discharge unit includes a scorotron having a grid electrode and a discharging electrode; an opposing electrode opposed to the grid electrode through the intermediate transfer member; a first voltage unit to apply a reverse polarity voltage of the toner images to the discharging electrode; a second voltage applying unit to apply a same polarity voltage of the toner images to the grid electrode; a cleaning unit of the grid electrode; a current detecting unit; and a controller to control a timing to clean the grid electrode according to the detected current.

Abstract: An cleaning apparatus includes: a first brush roll for removing toner from an image carrier; a second brush roll for removing the toner from the image carrier; a first recovery device for recovering the toner deposited on the first brush roll; a second recovery device for recovering the toner deposited on the second brush roll; a first electric field forming device for forming an electric field between the first brush roll and the image carrier; and a second electric field forming device for forming an electric field between the second brush roll and image carrier, wherein the first brush roll and the second brush roll each has a plurality of electrically conductive yarns arranged on a conductive core, and a resistance R2 of each of the yarns used in the second brush roll is smaller than 1×107 ?/cm.

Abstract: There is described a color image forming apparatus for forming a color image onto a transfer material by superimposing a plurality of unicolor toner images. The apparatus includes an intermediate transfer member onto which the plurality of unicolor toner images are successively transferred in such a manner that the plurality of unicolor toner images superimpose with each other, so as to form a full color toner image on the intermediate transfer member and a discharge section, in which a potential of the side plate is set at a polarity opposite to that of the grid electrode.

Abstract: A color image forming apparatus for forming a color image onto a transfer material by superimposing a plurality of unicolor toner images. The apparatus makes it possible to produce a high quality image through a secondary transferring operation with a good secondary transferring efficiency. At a pre-secondary transfer charge eliminating section, an electric potential difference between a grid electrode disposed at an upstream side and an opposing electrode is set at such a value that is greater than that between a grid electrode disposed at a downstream side and an opposing electrode.

Abstract: An cleaning apparatus includes: a first brush roll for removing toner from an image carrier; a second brush roll for removing the toner from the image carrier; a first recovery device for recovering the toner deposited on the first brush roll; a second recovery device for recovering the toner deposited on the second brush roll; a first electric field forming device for forming an electric field between the first brush roll and the image carrier; and a second electric field forming device for forming an electric field between the second brush roll and image carrier, wherein the first brush roll and the second brush roll each has a plurality of electrically conductive yarns arranged on a conductive core, and a resistance R2 of each of the yarns used in the second brush roll is smaller than 1×107 ?/cm.

Abstract: There is described an image forming apparatus equipped with a cleaning unit to clean a belt-type transfer member. The cleaning unit includes: a conductive opposing roller that contacts an inner surface of the intermediate transfer member; a first conductive brush member and a second conductive brush member, both of which are pressed against the conductive opposing roller while putting the intermediate transfer member between them; a cleaning-voltage applying power source to apply a cleaning voltage having a polarity opposite to that of the residual toner onto the first conductive brush member; and an opposing-roller potential controlling unit to control an electric potential state of the conductive opposing roller, so that an electric potential difference, between the first conductive brush member and the conductive opposing roller at a time when the secondary transferring unit is deactivated, is larger than that at a time when the primary transferring unit is activated.

Abstract: A color image forming apparatus includes: a plurality of image carriers each on which a toner image having a color different from each other is formed; an intermediate transfer member to which each of the image carriers is transferred; a plurality of a primary transfer units each which transfers a toner image formed on each of the plurality of image carriers onto the intermediate transfer member; a discharging unit provided between two adjoining image carriers in a moving direction of the intermediate transfer member, which discharges an electrical charge of a toner image transferred on the intermediate transfer member; and a secondary transfer unit which transfers a plurality colors of toner images which have been superimposed on the intermediate transfer member onto a transfer material.

Abstract: An image forming apparatus for a color print having an intermediate transfer belt and a plurality of image forming devices, wherein each image forming device has a photoreceptor and a developing device, and toner images formed on photoreceptors by the developing devices are primarily transferred onto the intermediate transfer belt to form a superimposed toner image and further the superimposed toner image is secondarily transferred in a batch onto a transfer member, the apparatus including: a charging or neutralizing device; a conductive elastic member, as a counter electrode for the charging or neutralizing device; and a belt surface regulating member disposed in a vicinity of the conductive elastic member to regulate a position of the surface of the intermediate transfer belt.

Abstract: The invention prevents the phenomenon of occurrence of toner scattering or density fluctuations by changing the appropriate transfer conditions according to the toner charge of the toner images formed on an intermediate image transfer member. The density of toner images formed under prescribed image forming conditions on an intermediate image transfer member is detected, the toner charge is obtained from the detected density, and the pre-transfer charging section is controlled according to the obtained toner charge.

Abstract: There is described an image forming apparatus equipped with a cleaning unit to clean a belt-type transfer member. The cleaning unit includes: a conductive opposing roller that contacts an inner surface of the intermediate transfer member; a first conductive blush member and a second conductive blush member, both of which are pressed against the conductive opposing roller while putting the intermediate transfer member between them; a cleaning-voltage applying power source to apply a cleaning voltage having a polarity opposite to that of the residual toner onto the first conductive blush member; and an opposing-roller potential controlling unit to control an electric potential state of the conductive opposing roller, so that an electric potential difference, between the first conductive blush member and the conductive opposing roller at a time when the secondary transferring unit is deactivated, is larger than that at a time when the primary transferring unit is activated.

Abstract: There is described an image forming apparatus equipped with a cleaning unit to clean a belt-type transfer member. The cleaning unit includes: a conductive opposing roller that contacts an inner surface of the intermediate transfer member; a first conductive blush member and a second conductive blush member, both of which are pressed against the conductive opposing roller while putting the intermediate transfer member between them; a cleaning-voltage applying power source to apply a cleaning voltage having a polarity opposite to that of the residual toner onto the first conductive blush member; and an opposing-roller potential controlling unit to control an electric potential state of the conductive opposing roller, so that an electric potential difference, between the first conductive blush member and the conductive opposing roller at a time when the secondary transferring unit is deactivated, is larger than that at a time when the primary transferring unit is activated.

Abstract: In the discharge section to correct the potential of toner image on the intermediate transfer body before the secondary image transfer and to obtain a good secondary transfer image, it is made that the opposite electrode is brought into contact with the back surface of the intermediate transfer body under the stable condition.

Abstract: An image forming apparatus including a primary transfer unit to transfer toner images of plural colors on image carriers onto an intermediate transfer member; a secondary transfer unit to transfer the toner images onto a transfer material; and a pre-secondary transfer discharge unit to discharge charges of the toner images, wherein the discharge unit includes a scorotron having a grid electrode and a discharging electrode; an opposing electrode opposed to the grid electrode through the intermediate transfer member; a first voltage unit to apply a reverse polarity voltage of the toner images to the discharging electrode; a second voltage applying unit to apply a same polarity voltage of the toner images to the grid electrode; a cleaning unit of the grid electrode; a current detecting unit; and a controller to control a timing to clean the grid electrode according to the detected current.

Abstract: An image forming apparatus, including an image forming section which forms a toner image on an image carrier, a primary transfer section which transfers the toner image formed by the image forming section on the image carrier from the image carrier to an intermediate transfer body, a secondary transfer section which transfers the toner image on the intermediate transfer body onto an image transfer material, an pre-secondary transfer electric discharging section which is located between the primary transfer section and the secondary transfer section to electrically discharge the toner image on the intermediate transfer body, and a control section which controls an output of the pre-secondary transfer electric discharging section, based on a smoothness of a surface of the image transfer material.

Abstract: A color image forming apparatus may have an image forming unit composed of a plurality of groups which have image carriers and image forming devices.

Abstract: A color image forming apparatus wherein the pre-secondary transfer electric charge eliminating device arranged intermediate between a primary transfer section and a secondary transfer section is provided with: a discharge electrode arranged on the side opposite to the toner carrier surface of an intermediate transfer member; and a counter electrode containing a discharge electrode and a conductive elastic member arranged at the opposed position beyond the intermediate transfer member so as to be pressed against the intermediate transfer member; wherein the pressing force of the aforementioned counter electrode against the rear surface of the intermediate transfer member is distributed in such a way that the pressure for the center of the intermediate transfer member is smaller than that for both ends thereof, in the transversal direction to the direction in which the intermediate transfer member rotates.