Abstract: The present disclosure is directed to suppressing image defects due to variations in the values of currents flowing through respective photosensitive drums during image formation, and reducing the absolute value of a voltage applied when a primary transfer power supply unit applies a voltage of polarity opposite to that during image formation, to primary transfer members. There is provided an image forming apparatus including a transfer member configured to make contact with an inner peripheral surface of a transfer belt, a first power supply unit configured to apply a voltage to the transfer member, a resistance element connected between the first power supply unit and the transfer member, and a diode connected in parallel with the resistance element in a direction in which a current flowing in a first direction is blocked and a current flowing in a second direction is passed.

Abstract: An image forming apparatus includes an image bearing member, a transfer member, a power source, a detection unit, and a fixing unit. The transfer member transfers a toner image to a transfer material from the image bearing member. The detection unit detects electric current flowing in the transfer member when the power source applies voltage to the transfer member. The fixing unit fixes a toner image to a transfer material by heat. The heat to the fixing unit is controlled where a subsequent transfer material conveyance stops after the transfer material is discharged from the fixing unit, in a case where a second current value, detected when voltage is applied to the transfer member contacting the fixing unit and the transfer member, is greater than a first current value detected when voltage is applied to the transfer member before the transfer material reaches the fixing unit.

Abstract: The image forming apparatus includes an image bearing member; an ionically conductive intermediate transferring belt; a primary transfer member; an opposing member that opposes the current supply member through the intermediate transferring belt, and a control unit configured to execute a recovery operation in a state where a primary transfer in which a toner image is primarily transferred to the image intermediate transferring belt from the image bearing member is not performed, wherein the recovery operation includes to supply a current flowing in a flow direction opposite to a flow direction of a current in the primary transfer through the opposing member from the current supply member to remove an uneven distribution of the conductive agent in the intermediate transferring belt caused by primary transfer.

Abstract: The present disclosure is directed to suppressing image defects due to variations in the values of currents flowing through respective photosensitive drums during image formation, and reducing the absolute value of a voltage applied when a primary transfer power supply unit applies a voltage of polarity opposite to that during image formation, to primary transfer members. There is provided an image forming apparatus including a transfer member configured to make contact with an inner peripheral surface of a transfer belt, a first power supply unit configured to apply a voltage to the transfer member, a resistance element connected between the first power supply unit and the transfer member, and a diode connected in parallel with the resistance element in a direction in which a current flowing in a first direction is blocked and a current flowing in a second direction is passed.

Abstract: An image forming apparatus includes an image bearing member, a transfer member, a power source, a detection unit, and a fixing unit. The transfer member transfers a toner image to a transfer material from the image bearing member. The detection unit detects electric current flowing in the transfer member when the power source applies voltage to the transfer member. The fixing unit fixes a toner image to a transfer material by heat. The heat to the fixing unit is controlled where a subsequent. transfer material conveyance stops after the transfer material is discharged from the fixing unit, in a case where a second current value, detected when voltage is applied to the transfer member contacting the fixing unit and the transfer member, is greater than a first current value detected. when voltage is applied to the transfer member before the transfer material reaches the fixing unit.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for transferring the toner image from the image bearing member onto a transfer material; an electric power supplying device, contacted to the belt, to which a voltage is to be applied, wherein the electric power supplying device includes an erected fiber portion formed with a plurality of electroconductive erected fibers contacted to the belt; a power source; and a contact member, connected to the electric power supplying device, for applying the voltage from the power source to the electric power supplying device. The electric power supplying device includes a welded portion formed by heat aggregation of a part of the erected fiber portion, and the contact member is connected to the welded portion.

Abstract: A position of a contact region formed between a transfer belt and a transfer member in the form of a brush is displaced toward a downstream side in a movement direction of the transfer belt with respect to the position in an initial state, whereby it is difficult to acquire excellent transferability. An image forming apparatus, in which a plurality of conductive fibers contacts an inner circumferential surface of the transfer belt, includes a support device configured to support the transfer member in such a manner that the plurality of conductive fibers is pressed between the support device and the transfer belt. A tilt amount of the conductive fiber, which is generated due to a movement of the transfer belt, is smaller than a length of a region where an image bearing member and the transfer belt contact each other in the movement direction of the transfer belt.

Abstract: An image forming apparatus includes image bearing members, cleaning blades for removing toner from corresponding image bearing members, and developing devices for developing an electrostatic latent image on corresponding image bearing members with toner. The image forming apparatus is operable in a monochromatic mode in which the toner image is formed only on a predetermined one of the image bearing members, and no image is formed on the other image bearing member. In a monochromatic mode operation, a controller starts to drive the plurality of image bearing members in synchronism with each other in a state that the other image bearing member is spaced from a belt and the predetermined image bearing member is in contact with the belt. The controller is capable of executing a supplying operation for supplying the toner from the developing devices to the cleaning blades by way of the image bearing members, respectively.

Abstract: The present invention ensures stable cleaning performance with respect to remaining toner on an intermediate transfer belt without increasing the size and cost of an image forming apparatus. The present invention provides an image forming apparatus in which residual toner charged by a toner charging member is transferred from the intermediate transfer belt to a photosensitive drum, the toner charging member is placed with respect to the intermediate transfer belt in a rotation direction of the intermediate transfer belt such that a first distance of the intermediate transfer belt from a position where a secondary transfer member contacts the intermediate transfer belt to a position where the toner charging member contacts the intermediate transfer belt is longer than a second distance from the position where the toner charging member contacts the intermediate transfer belt to a position where an image bearing member placed most upstream contacts the intermediate transfer belt.

Abstract: A position of a contact region formed between a transfer belt and a transfer member in the form of a brush is displaced toward a downstream side in a movement direction of the transfer belt with respect to the position in an initial state, whereby it is difficult to acquire excellent transferability. An image forming apparatus, in which a plurality of conductive fibers contacts an inner circumferential surface of the transfer belt, includes a support device configured to support the transfer member in such a manner that the plurality of conductive fibers is pressed between the support device and the transfer belt. A tilt amount of the conductive fiber, which is generated due to a movement of the transfer belt, is smaller than a length of a region where an image bearing member and the transfer belt contact each other in the movement direction of the transfer belt.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for transferring the toner image from the image bearing member onto a transfer material; an electric power supplying device, contacted to the belt, to which a voltage is to be applied, wherein the electric power supplying device includes an erected fiber portion formed with a plurality of electroconductive erected fibers contacted to the belt; a power source; and a contact member, connected to the electric power supplying device, for applying the voltage from the power source to the electric power supplying device. The electric power supplying device includes a welded portion formed by heat aggregation of a part of the erected fiber portion, and the contact member is connected to the welded portion.

Abstract: An image forming apparatus includes a plurality of image bearing members; a belt for receiving toner images from the image bearing members and for transferring the toner image onto a transfer material; a controller for driving the image bearing members; and wherein the image forming apparatus is operable in a monochromatic mode in which the toner image is formed only on a predetermined one of the image bearing members, and no image is formed on the other image bearing member, wherein in a operation in the monochromatic mode, the controller starts to drive the plurality of image bearing members in synchronism with each other in a state that the other image bearing member is spaced from the belt, and the predetermined image bearing member is in contact with the belt.

Abstract: There is provided an image forming apparatus which shortens the time taken for circumference detection and measures the circumference at high precision without obstructing downsizing of the apparatus. To accomplish this, the image forming apparatus detects, at an arbitrary timing, the physical pattern of the image-formed surface of a rotation member that changes over time. In the second round, the image forming apparatus detects the second pattern at a timing a predetermined time after the arbitrary timing. By using the detected patterns, the image forming apparatus obtains information associated with the circumference of the rotation member.

Abstract: An image forming apparatus including, a plurality of image bearing members, a plurality of developing units which includes toner storage containers and a belt transferring toner images onto a transfer material, the image forming apparatus being capable of executing a first cleaning mode and a second cleaning mode to move the toner adhering onto the belt onto the image bearing members and to collect the adhering toner into the toner storage containers, wherein, in the first cleaning mode, the adhering toner is collected into the toner storage container of the developing unit developing a black toner, and in the second cleaning mode, a portion of the adhering toner is collected into the toner storage container corresponding to the image bearing member located at a most upstream position and a rest of the adhering toner is collected into the toner storage container of the developing unit developing the black toner.

Abstract: In full-color printing, one of first and second rotary members is activated with a time lag after the other of the first and second rotary members is activated such that the phase difference between the first and second rotary members is an adjusted phase difference. In addition, every time monochrome printing is performed, the time lag is changed.

Abstract: An image forming apparatus which predicts VL fluctuates of a photosensitive drum, taking a rotation speed of the photosensitive drum during image formation into consideration, and controls the image formation based on the prediction, for always obtaining an image of a stable density. The image forming apparatus performs appropriate image formation control by controlling image forming conditions based on a photosensitive member rotation time, a photosensitive member stop time, a temperature of the environment, an absolute humidity of the environment, and the rotation speed of the photosensitive member.

Abstract: The present invention ensures stable cleaning performance with respect to remaining toner on an intermediate transfer belt without increasing the size and cost of an image forming apparatus. The present invention provides an image forming apparatus in which residual toner charged by a toner charging member is transferred from the intermediate transfer belt to a photosensitive drum, the toner charging member is placed with respect to the intermediate transfer belt in a rotation direction of the intermediate transfer belt such that a first distance of the intermediate transfer belt from a position where a secondary transfer member contacts the intermediate transfer belt to a position where the toner charging member contacts the intermediate transfer belt is longer than a second distance from the position where the toner charging member contacts the intermediate transfer belt to a position where an image bearing member placed most upstream contacts the intermediate transfer belt.

Abstract: An image forming apparatus including, a plurality of image bearing members, a plurality of developing units which includes toner storage containers and a belt transferring toner images onto a transfer material, the image forming apparatus being capable of executing a first cleaning mode and a second cleaning mode to move the toner adhering onto the belt onto the image bearing members and to collect the adhering toner into the toner storage containers, wherein, in the first cleaning mode, the adhering toner is collected into the toner storage container of the developing unit developing a black toner, and in the second cleaning mode, a portion of the adhering toner is collected into the toner storage container corresponding to the image bearing member located at a most upstream position and a rest of the adhering toner is collected into the toner storage container of the developing unit developing the black toner.

Abstract: An image forming apparatus which predicts VL fluctuations of a photosensitive drum in consideration of a double-sided print mode, and performs an image formation control based on the prediction, and thus always obtains a stable density image. The image forming apparatus performs an appropriate image formation control by controlling an image forming condition based on a photosensitive member rotation time, a photosensitive member stop time, a temperature of an atmospheric environment, an absolute humidity of the atmospheric environment, and whether an image formation that precedes a subsequent image formation is performed in single-sided printing or double-sided printing.

Abstract: In full-color printing, one of first and second rotary members is activated with a time lag after the other of the first and second rotary members is activated such that the phase difference between the first and second rotary members is an adjusted phase difference. In addition, every time monochrome printing is performed, the time lag is changed.