Abstract: A charging device including: a first charger which charges a member to be charged, the first charger having conducting particles which come into contact with the member to be charged; a second charger which charges the member to be charged in a same polarity as charging polarity of the first charger on an upstream side of the first charger in a moving direction of the member to be charged; and a controller which controls application of a charging voltage to the first charger, in which the controller turns a charging voltage on or off in an area of the member to be charged which is not subjected to charging by the second charger.

Abstract: An image forming apparatus including a first unit having a developer container holding developer containing toner and carrier, and a developer holder to hold and transfer the developer held in the developer container, a second unit to supply toner to the developer container, and a processing unit to determine the time of replacement of the first unit, from information on a toner supply amount from the second unit or information on an operation amount of the developer holder.

Abstract: An image forming apparatus including an image bearing member bearing latent images; a developing unit including plural developing devices developing the latent images with developers to form visual images, each developing device including a developer bearing member bearing the developer to develop the latent image, and a developer thickness controlling member contacting the developer bearing member to control the thickness of a developer layer on the developer bearing member; and a driving device including at least one driving source, a forward rotation driving member rotated by the driving source to drive the developer bearing members to forwardly rotate to develop the latent images, and a reverse rotation driving member rotated by the driving source to drive the developer bearing members to reversely rotate when the developing operation is not performed, wherein the forward rotation driving member and the reverse rotation driving member can operate at the same time.

Abstract: The image forming apparatus comprises a photoconductor, a latent electrostatic image forming unit for forming a latent electrostatic image on the photoconductor, a developing unit for developing the latent electrostatic image using a developer comprising a toner to form a visible image, a transfer unit for transferring the visible image to a recording medium, a cleaning unit for removing the developer remained on the photoconductor surface and a developer amount detection unit for detecting developer amount adhering to the photoconductor surface by a reflecting photosensor, wherein the developer stirring time per copy when one copy is made from an original, is 2 to 6 times the developer stirring time per copy when two or more copies are made from the original, wherein the toner comprises at least a binder resin and a wax, and the dynamic frictional coefficient of the toner is 0.15 to 0.45.

Abstract: A process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The main assembly includes an output contact movable between electrical connecting and retracting positions, a displaceable member for moving the output contact, and an elastic member for elastically urging the displaceable member to urge the output contact toward the retracted position. The process cartridge includes a drum, a process device actable on the drum, an operating member, a movable operation member operable by the operating member, after mounting the cartridge to the main assembly, to move the displaceable member, in interrelation with which the output contact is moved from the retracted to the electrical connection position against an elastic force of the elastic member, and an input electrical contact for receiving a voltage enabling the process device by engagement with the output contact moved to the electrical connecting position.

Abstract: A laser printer (10) having a fuser (220) to fix toner on sheets (214) in which the fuser element (225) heated by the power supply (121) of the printer is not capable of drawing enough power from the power supply to cause flicker. Thick or heavy media require more heat energy than paper. At cold-fuser start, the use of thick or heavy media is identified to the control system (14) and the control system adds a predetermined period to the normal delay to start printing. This invention may be implemented by a small addition to control software.

Abstract: An image forming apparatus includes a process cartridge, a toner storage, and a toner supplying unit. The process cartridge includes an image bearing member, a developer container, a developer bearing member, and a pair of side plates. The developer container includes a toner inlet mounted at a predetermined position on one of its top surface. The pair of side plates are arranged in parallel and separated by a predetermined distance which determines a predetermined longitudinal width of the process cartridge and configured to support the components in the process cartridge.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly including an output contact movable between an electrical connecting position and a retracted position retracted from the electrical connecting position. The process cartridge includes a movable operation member movable relative to a cartridge frame, wherein when the process cartridge is inserted into the main assembly of the apparatus, the movable operation member is engageable with a fixed engageable member fixed in the main assembly of the apparatus to move relative to the cartridge frame, and is engageable with a displaceable engaging portion of the displaceable member to move the output contact from the retracted position to the electrical connecting position; and an input electrical contact for receiving a voltage for enabling the process device by engagement with the output contact moved to the electrical connecting position.

Abstract: A fixing device including a fixing belt module is formed of a fixing roller having a heat source, one or more tension rollers at a fixing side and an endless fixing belt looped and stretched around the rollers to thereby rotate and a pressure belt module including an endless pressure belt that comes in contact with an outer peripheral surface of the fixing belt only within a range of a section where the fixing belt is wrapped around a surface of the fixing roller, thereby forming a nip section for fixation between itself and the fixing belt. The fixing belt module includes a fixing belt heating unit that heats an inner peripheral surface and/or the outer peripheral surface of the fixing belt at any sections other than the section where the fixing belt is wrapped around the outer peripheral surface of the fixing roller.

Abstract: A developing cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The cartridge includes a developing roller, for developing an electrostatic latent image formed on an electrophotographic photosensitive member, having an elastic roller portion and a shaft portion supporting the elastic roller portion, a developer regulating member; a protecting member including a contact portion provided for contact with the elastic roller portion when the protecting member is demountably mounted between the developing roller and the developer regulating member; and a supporting portion for supporting the contact portion and provided for contact with the elastic roller portion when the protecting member is demountably mounted between the developing roller and the developer regulating member. The contact portion has a hardness which is not less than a predetermined value and not more than a hardness of the elastic roller portion.

Abstract: A charge removing unit is provided in order to control the surface potential of an image bearing element by removing charge from a surface of the image bearing element before a toner image is transferred from the image bearing element to a transfer medium. Surface potential controlling units are provided upstream of a contact area between the image bearing element and the transfer medium in order to control the surface potential of the transfer medium so that a toner on the image bearing element does not shift to the transfer medium.

Abstract: The positioning of an image read sensor for accurately reading the toner image on the belt member becomes easy. The image read sensor 21 is located on the supporting frame 26 provided to the casing of the image forming apparatus so that it faces the belt member such as an intermediate transfer belt 45 between the driving roller 46 and follower roller 48 when the belt unit is mounted to the casing of the apparatus. The supporting frame 26 is provided with shaft supporting recesses 27. The shaft member is supported for rotation in the belt unit such that it contacts the inside surface of the belt member and pushes the belt member outward at the position it faces the image read sensor across the belt member when the belt unit is mounted to the casing of the apparatus.

Abstract: An exhaust system of a liquid electrophotography printer includes: an exhaust line to discharge air inside an engine cell to an outside thereof; at least one exhaust fan, which is installed inside the exhaust line to generate and move the air inside the engine cell; a heating coil to heat the air to be discharged through the exhaust line to ignite impurities contained in the air; and an oxidative catalyst filter to filter and deodorize the impurities. The heating coil may be installed inside the exhaust line and coated with platinum on the outer surface. The oxidative catalyst filter may be installed inside the exhaust line, and may be a metallic honeycomb carrier coated with a catalyst mixture, or a non-woven heating mat coated with a catalyst mixture. The heating coil and the oxidative catalyst filter are typically sequentially installed adjacent to each other.

Abstract: An image forming apparatus is provided which includes an image formation unit for forming images on a recording medium; a first transporting path for discharging a recording medium to a sheet discharge device; a longer second transporting path for reversing the transportation direction of the recording medium; a transporting path switching unit for switching between the first transporting path or the second transporting path; a setting unit for setting the discharge speed for discharging the recording medium from the first and second transporting paths to a recording sheet stacking unit, and also setting the reverse transportation speed; and a determining unit for determining whether or not the sheet discharge device has been connected to the image forming apparatus; wherein the setting unit sets a first discharge speed slower than the reverse transportation speed in the event that the sheet discharge device has not been connected, and otherwise sets a faster second discharge speed.

Abstract: The fixing apparatus prevents transfer paper from sticking or jamming. This fixing apparatus is intended to fix polymerized toner on transfer material and has a heating roller and a pressure roller. The difference in hardness between the heating roller and pressure roller is 5 through 10 degrees in AskerC, and the hardness of the pressure roller is higher than that of the heating roller. A fixing nip portion, convex-shaped on the side closest to the heating roller, is formed between the heating roller and pressure roller and the nip pressure of the fixing nip portion is 24.5 N/cm or more.

Abstract: An image forming apparatus capable of connecting to a sheet post-processing equipment, includes an image data inputting unit which inputs a plurality of pages of image data to be formed as images on sheets; an image forming unit configured to form the image on the sheet based on the image data inputted with the inputting unit; a retaining unit including a first conveying path branching from a second conveying path of the sheet post-processing equipment, the retaining unit temporarily retaining the sheet, and then while the sheet post-processing equipment is performing post-processing of a sheet bundle, conveying the sheet to the sheet post-processing equipment; and a control unit which differentiates an order of pages on which the image is formed from an order of pages at a time of normally forming the image in the sheet bundle, to which the sheet post-processing equipment performs the post-processing.

Abstract: A two part cartridge having a photoconductor part (1) and a toner part (5) having no force biasing element on either part. The two parts fit together so that a developer roller (7) in the toner part contacts a photoconductor drum (3) in the other part. When the two parts are installed in a printer the cover (50), when closed, brings a spring (62) into contact with one side of the toner part while the frame (F) of the printer blocks movement away from the cover. An advantage of the two part cartridge is that the toner part can be replaced without replacing the photoconductor part. Members on the cartridge for force biasing are avoided and the need for training or skill to latch the parts together is avoided.

Abstract: A charging device including: a charging roller having a metal cylinder and an elastic layer located on the metal cylinder; a cleaner configured to clean the charging roller, which includes an electroconductive brush roller including a roller having a shaft; and hair located overlying the roller, wherein the hair includes a fiber which has a width of from 0.1 to 20 denier, and a length of from 0.3 to 2.5 mm and which is planted at a density of from 7,000 to 46,000 lines/cm2, and a member configured to impart substantially the same potential as that of the charging roller to the electroconductive brush roller when a bias voltage is applied to the charging roller. A process cartridge and an image forming apparatus including the charging device are also provided.

Abstract: A charging device includes a charging member disposed opposite to a surface of an image carrier. The image carrier is charged by applying a voltage to the charging member, and the charging member includes a substrate and a resistor layer thereon. The resistor layer is disposed with two spacers contacting with the image carrier, so that a gap is created between the image carrier and the resistor layer between the two spacers, wherein width variation of the gap with time is prevented. The end portions of the resistor layer of the charging member protrude above the resistor layer between them, and the spacers are constituted by protrudent fractions of the end portions of the resistor layer.

Abstract: If a temperature of a heat roller 12 rises abnormally, a thermostat 54 operates. When the thermostat 54 operates, a conduction path to an excitation coil 91 of a relay 90 is cut off so that a normally open contact 92 of the relay 90 can be operated. When the normally open contact 92 operates, the supply path of a drive signal supplied from a frequency variable oscillator 81 to a transistor 63 is cut off. By the cut-off, a high-frequency current does not flow through coils 14a to 14c; therefore, induction heating with respect to the heat roller 12 is stopped.