Abstract: An image forming apparatus includes a transfer belt, a pressure receiving roller, a secondary transfer roller, and a belt movement restricting section. The belt movement restricting section is disposed close to the back of the belt. When pressing the belt between the pressure receiving roller and the secondary transfer roller, and nipping paper between the belt and the secondary transfer roller, an angle defined by the portion, upstream from the secondary transfer roller, of the belt and an imaginary line connecting the pressure-receiving-roller axis with the secondary-transfer-roller axis is less than 90 degrees. During non-secondary-transfer mode, the belt movement restricting section is separated from the belt. During secondary transfer, the belt movement restricting section holds the belt not to let the belt pushed by the paper move toward the pressure receiving roller.

Abstract: A cleaning device for cleaning a belt member, includes a cleaning blade; a removing member coming in contact with the surface of the belt member so as to remove foreign matter adhering on the surface of the belt member; and a contact pressure changing section to change a contact pressure between the removing member to the belt member, wherein, when the contact pressure between the removing member and a region of the belt member corresponding in position to a toner image to be not transferred to a paper sheet is made P1, and the contact pressure between the removing member and a region of the belt member corresponding in position to a toner image to be transferred to a paper sheet is made P2, the contact pressure changing section changes the contact pressure to satisfy the conditional formula: (P1<P2).

Abstract: An image forming apparatus including: a transfer belt; a rotational body; a transfer roller that forms a transfer nip part between the transfer roller and the rotational body with the transfer belt therebetween; a pressing section that presses one of the rotational body and the transfer roller against the other of the rotational body and the transfer roller; and a controlling section that controls the pressing section so as to change the pressing direction of the rotational body or the transfer roller in accordance with a predetermined image formation condition.

Abstract: An image forming apparatus including: a rotatable image bearing member; and a brush roller that rotates in a counter direction to a rotational direction of the image bearing member with a bristle portion being in sliding contact with an image bearing surface of the image bearing member. The bristle portion is inclined forward in the rotational direction of the brush roller.

Abstract: An image forming apparatus includes: a transfer belt that is stretched on a plurality of support rollers including a backup roller in a loop-like manner and has an outer surface for carrying thereon a toner image; a transfer roller that is brought into pressurized contact with the backup roller across the transfer belt and forms a transfer nip with the transfer belt; a restriction member that is placed upstream of a transfer nip in a sheet conveying direction so as to be switchable between a first state in which the restriction member is brought closer to an inner surface of the transfer belt and a second state in which a distance of the restriction member from the inner surface of the transfer belt is larger than that in the first state; and a control section that switches a state of the restriction member.

Abstract: An image forming apparatus including a transfer section for transferring a toner image formed on an image bearing member onto a sheet by pressure contact of the sheet against the image bearing member with a transfer member; a cleaning section having a cleaning blade to remove residual toner on the image bearing member; and a control section for controlling a rotation of the image bearing member so as to carry out a return action of a blade configuration which stops or reverses the rotation of the image bearing member, when the rotation amount reaches a predetermined value, wherein the control section additionally carries out the return action when the rotation amount reaches a value smaller than the predetermined value, in a case where a size of a sheet in a current job is larger than a size a sheet having been passed through in a previous job.

Abstract: An electric charge eliminating device for eliminating electric charge on an image carrying member or on a recording medium carrying member which is incorporated in an image forming apparatus, comprises a needlelike electrode having a plurality of protruding sections which form a plurality of discontinuous discharge points; an insulating holder for holding the needlelike electrode; a discharging power source for applying an electric voltage to the needlelike electrode; and a conductive shielding member arranged between the needlelike electrode and the image carrying member or the recording medium carrying member.

Abstract: An image forming apparatus includes: a cleaning blade provided on an intermediate transfer member to which a toner image formed on at least one image forming section is primary transferred and on a secondary transfer section which transfers the toner image transferred on the intermediate transfer member onto a transfer material, respectively, which cleans the toner image remained thereon, respectively; a bias power source which is electrically connected to the secondary transfer section; and a controller which causes the image forming section to form a patch toner image onto a non-image area on the image carrier corresponding to an area between adjoining two transfer materials, and causes the bias power source to conduct a power control in synchronization with a positional movement timing of the patch toner image, to supply selectively the patch toner image to the intermediate transfer member and the secondary transfer section.

Abstract: An image forming apparatus includes a transfer belt, a pressure receiving roller, a suspension roller, a secondary transfer roller, and an endless support belt. The support belt is stretched over at least one of the pressure receiving roller and the suspension roller. When pressing the transfer belt between the pressure receiving roller and the secondary transfer roller, and nipping paper between the transfer belt and the secondary transfer roller, an angle defined by the portion, upstream from the secondary transfer roller, of the transfer belt and an imaginary line connecting the pressure-receiving-roller axis with the secondary-transfer-roller axis is less than 90 degrees. A part of the support belt is held between the transfer belt and at least one of the two rollers over which the support belt is stretched.

Abstract: An image forming apparatus includes a transfer belt, a pressure receiving roller, a secondary transfer roller, and a belt movement restricting section. The belt movement restricting section is disposed close to the back of the belt. When pressing the belt between the pressure receiving roller and the secondary transfer roller, and nipping paper between the belt and the secondary transfer roller, an angle defined by the portion, upstream from the secondary transfer roller, of the belt and an imaginary line connecting the pressure-receiving-roller axis with the secondary-transfer-roller axis is less than 90 degrees. During non-secondary-transfer mode, the belt movement restricting section is separated from the belt. During secondary transfer, the belt movement restricting section holds the belt not to let the belt pushed by the paper move toward the pressure receiving roller.

Abstract: An image forming apparatus including a transfer section for transferring a toner image formed on an image bearing member onto a sheet by pressure contact of the sheet against the image bearing member with a transfer member; a cleaning section having a cleaning blade to remove residual toner on the image bearing member; and a control section for controlling a rotation of the image bearing member so as to carry out a return action of a blade configuration which stops or reverses the rotation of the image bearing member, when the rotation amount reaches a predetermined value, wherein the control section additionally carries out the return action when the rotation amount reaches a value smaller than the predetermined value, in a case where a size of a sheet in a current job is larger than a size a sheet having been passed through in a previous job.

Abstract: An image forming apparatus including: an image forming section having a intermediate transfer body to carry a toner image on a photoreceptor and transfer the toner image onto a sheet of paper; a cleaning section for removing residual toner on the intermediate transfer body by bringing a cleaning blade into close contact with the intermediate transfer body; and a control section for controlling a rotation of the intermediate transfer body so as to carry out a return action of a blade configuration which stops or reverses the rotation of the intermediate transfer body, when a rotation amount reaches a predetermined value, wherein the control section carries out the return action when the rotation amount reaches a value smaller than the predetermined value, in a case where a plurality of previous printing jobs is determined to be intermittent printing.

Abstract: A cleaning device for cleaning a belt member, includes a cleaning blade; a removing member coming in contact with the surface of the belt member so as to remove foreign matter adhering on the surface of the belt member; and a contact pressure changing section to change a contact pressure between the removing member to the belt member, wherein, when the contact pressure between the removing member and a region of the belt member corresponding in position to a toner image to be not transferred to a paper sheet is made P1, and the contact pressure between the removing member and a region of the belt member corresponding in position to a toner image to be transferred to a paper sheet is made P2, the contact pressure changing section changes the contact pressure to satisfy the conditional formula: (P1<P2).

Abstract: An image forming apparatus includes: a cleaning blade provided on an intermediate transfer member to which a toner image formed on at least one image forming section is primary transferred and on a secondary transfer section which transfers the toner image transferred on the intermediate transfer member onto a transfer material, respectively, which cleans the toner image remained thereon, respectively; a bias power source which is electrically connected to the secondary transfer section; and a controller which causes the image forming section to form a patch toner image onto a non-image area on the image carrier corresponding to an area between adjoining two transfer materials, and causes the bias power source to conduct a power control in synchronization with a positional movement timing of the patch toner image, to supply selectively the patch toner image to the intermediate transfer member and the secondary transfer section.

Abstract: An electric charge eliminating device for eliminating electric charge on an image carrying member or on a recording medium carrying member which is incorporated in an image forming apparatus, comprises a needlelike electrode having a plurality of protruding sections which form a plurality of discontinuous discharge points; an insulating holder for holding the needlelike electrode; a discharging power source for applying an electric voltage to the needlelike electrode; and a conductive shielding member arranged between the needlelike electrode and the image carrying member or the recording medium carrying member.

Abstract: An image forming apparatus provided with a cleaning device including a cleaning blade in contact with an image carrier with contact pressure for removing the toner remaining on the image carrier; a toner guide roller which is located upstream of the cleaning blade in the rotating direction of the image carrier and which rotates in contact with the image carrier; a toner ejection regulating member in contact with the toner guide roller to eject the remaining toner appropriately; and a space formed by the enclosure of the image carrier, cleaning blade, toner guide roller and toner ejection regulating member for the purpose of storing the remaining toner; and this image forming apparatus further includes a control device that controls the cleaning device so as to change the peripheral speed ratio of the toner guide roller with respect to the image carrier, in response to change in the system speed.

Abstract: An image forming apparatus provided with a cleaning device including a cleaning blade in contact with an image carrier with contact pressure for removing the toner remaining on the image carrier; a toner guide roller which is located upstream of the cleaning blade in the rotating direction of the image carrier and which rotates in contact with the image carrier; a toner ejection regulating member in contact with the toner guide roller to eject the remaining toner appropriately; and a space formed by the enclosure of the image carrier, cleaning blade, toner guide roller and toner ejection regulating member for the purpose of storing the remaining toner; and this image forming apparatus further includes a control device that controls the cleaning device so as to change the peripheral speed ratio of the toner guide roller with respect to the image carrier, in response to change in the system speed.