Abstract: In a standby time period in which a heating roller and a press roller are heated in a state in which a to-be-fixed medium is not fed, a fixation control section for driving and controlling a fixing device intermittently drives a motor, thereby varying a temperature of the press roller between a fixing ratio preferential mode and an energy-saving preferential mode.

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: An apparatus and procedure for the separation of a fixing roller from the print material, wherein, contamination of the print machine and the print material by release oil is avoided. A toner layer is applied to the printing material and, at minimum, a release material layer is directly applied to the printing material, upstream of the fixing roller, which makes possible reliable separation of the fixing roller from the print material.

Abstract: A fuser for an electrophotographic printer or copier has a fuser roll and pressure roll that form a nip through which a recording paper having a toner image is passed to fuse the toner image thereon. The fuser includes a cleaning web system to clean the fuser roll having a web supply roll, a tension roll to press the web against the fuser roll, and a web take up roll. To prevent spooling of the web from the supply roll during a paper jam clearance while the pressure roll is in contact with the fuser roll, a torsion spring is mounted on the tension roll shaft. The torsion spring provides enough torsional force on the tension roll to prevent rotation thereof during a jam clearance, thus preventing web spooling. During normal operation, the take up roll intermittently overcomes the torsion spring to step the web thereon.

Abstract: In an image forming system, an image forming device and a post-treatment device are provided so as to keep a distance L therebetween, by a positioning member and a transfer relaying device, and the image forming device is connected with the post-treatment device by the transfer relaying device. With this arrangement, a space surrounded by the image forming device, post-treatment device, positioning member, and transfer relaying device is made. On this account, it is possible to provide an image forming system in which an image forming device is coupled with a peripheral unit, which does not require cumbersome operations to make a space between the image forming device and the peripheral unit, on the occasion of carrying out unjamming treatment between the image forming device and the peripheral unit.

Abstract: A developer container storing a developer of the present invention includes a developer outlet formed in the side wall thereof, and a shutter member for selectively opening or closing the developer outlet. The shutter member opens the developer outlet when the developer container is mounted to the body of an image forming apparatus or closes it when the former is dismounted from the latter. The toner container with this configuration surely prevents the developer from leaking when the developer container is dismounted from an image forming apparatus.

Abstract: A method for minimizing toner usage in minimum area coverage patches in a color printer including: reviewing a print job including job images; performing a pixel count for each color plane on a sheet level of the print job; converting the pixel count to a percent area coverage per color plane; in feed-forward mode comparing the area coverage per color plane to a reference value; activating or inactivating a color station depending on the comparison of the area coverage per color plane to the reference value; and printing a MAC patch of variable size with the color station if the area coverage per color plane is substantially less than a reference value.

Abstract: A method and apparatus for driving a belt is provided. Included is a method and apparatus for searching for a home position of a steering roller for adjusting a position of the belt in a widthwise direction of the belt and placing the steering roller in the home position. The steering roller is moved from the home position to a balance point, in which an amount of variation of the belt in the widthwise direction is less than a predetermined value, or moved to a position of the steering roller that corresponds to a previously driven final position of the belt. The belt is driven in this state such that the amount of initial weaving of the belt is reduced. Thus, an amount of initial weaving of the belt when the belt is driven can be minimized such that a time to obtain images with suitable registration can be greatly reduced.

Abstract: A liquid image developing system, including a cartridge in which a developer is stored; a supply line; a development container to which the developer is supplied from the cartridge through the supply line; a photosensitive body in the development container; a development roller partially soaked in the developer in the development container and rotating opposite to the photosensitive body; a depositing member to create a potential difference required to attach the developer to a circumference of the development roller, opposite to the development roller; a metering blade to scratch the developer attached to the circumference of the development roller to a predetermined thickness; and an agitator to agitate the developer contained in the development container. Accordingly, a high-concentration developer can be directly used in the development operation without a dilution operation, and thus the structure to supply the developer can be considerably simplified.

Abstract: In a developing device of the present invention for depositing toner on an image carrier to thereby develop a latent image formed thereon, a toner refilling device is configured to refill, when the toner is short, fresh toner at a position where the developing device is situated.

Abstract: A CPU computes a saturation moisture content on the basis of a temperature and a relative humidity detected by environment detection means, and multiplies the saturation moisture content by a square of the relative humidity, thus obtaining an environment parameter value. The CPU sets a proper development contrast potential using the environment parameter value according to a correlative approximation expression with pre-calculated development contrast potentials.

Abstract: The present invention provides an image forming apparatus comprising an image bearing member for bearing a toner image, a movable intermediate transferring member, a first charging member for charging toner on the intermediate transferring member when it is applied with a voltage including an AC component, and a second charging member for charging toner on the intermediate transferring member when it is applied with a DC voltage, the second charging member being located on an upstream side of the first charging member with respect to a moving direction of the intermediate transferring member, wherein a toner image on the image bearing member is temporarily transferred to the intermediate transferring member and then transferred to a transfer material.

Abstract: A fixing device includes a fixing heater for being supplied with an AC voltage to generate heat; control means for variably controlling power of supplied electric energy to the fixing heater, wherein one cyclic period for changing the electric power comprises a plurality of waves, and the one cyclic period including a portion in which an electric power supply phase is changed and a portion in which a number of waves of the electric power supply is controlled.

Abstract: An image forming apparatus having a uniform nip between a photosensitive body and a transfer body. The image forming apparatus has a photosensitive unit on which an electrostatic latent image is formed, a developer feed unit to feed a developer onto the electrostatic latent image to form a visible image, and a transfer unit. The transfer unit has a curved side of a semi-hollow tubular shape that contacts the photosensitive unit, and a planar side opposite the curved side and secured at a support member, to transfer the visible image formed on the photosensitive unit to a recording medium. The curved side of the transfer unit has a uniform radius of curvature in an axial direction. Accordingly, the image forming apparatus can not only maintain a constant nip in relation to electrical resistance and contact pressure, but can also adjust the electrical resistance of the transfer unit by appropriately setting factors such as volume resistivity of the conductive elastic member.

Abstract: An image forming apparatus includes an image carrier and a first developing unit for forming an image on the image carrier using at least one type of first developer to which a second developing unit for forming an image using at least one type of second developer which differs from the first developer is installable. The apparatus includes a developing unit determination part for determining the type of developing unit of the image forming apparatus, and an announcement part for announcing to the user that, when the second developing unit is not installed and an image formation instruction for instructing the formation of an image obtained by using the second developer is inputted, the image formation instruction cannot be made to effect a response.

Abstract: An electrophotographic image forming apparatus having a photosensitive member 1, a charging roller 2 and a developing roller 31, and including an output variable power source 8 common to the charging and the developing rollers 2 and 31 for applying voltages to the charging and developing rollers 2 and 31, respectively, a power source output control portion 9, and a voltage changing device (Zener diode D1) interposed between the developing roller 31 and the power source 8, wherein, when the voltages applied to the charging and developing rollers 2 and 31 are raised to and lowered from voltages required for image formation, respectively, the control portion 9 controls an output of the power source 8 to perform the raising and lowering of the applied voltages for a predetermined time while keeping a potential difference for suppressing movement of developer onto the photosensitive member 1 between the voltages applied to the charging and developing rollers 2 and 31.

Abstract: A method of controlling a charging potential of an organic photoconductive cell (OPC) includes a first operation of applying two charging voltages Vc1 and Vc2 having respective duties D1 and D2 established in an engine controller unit (ECU) to a conductive roller via a high voltage power supply (HVPS) to charge the OPC, a second operation of measuring sensing voltages Vs1 and Vs2 through a sensing resistor Rs coupled to the conductive roller so that the ECU establishes a target charging current it and calculates a new charging voltage Vc3 and a new duty D3, a third operation of applying the new charging voltage Vc3 and the new duty D3 to the conductive roller via the HVPS to charge the OPC and measuring a charging current Ic3 of the conductive roller, and a fourth operation of comparing a difference between the charging current Ic3 of the conductive roller and the target charging current It with a tolerance value TOL to control the charging potential by using the target charging current when the difference is

Abstract: A transfer member transporting section is disposed so as to bring a tip end of a transfer member into contact with a peripheral face of a transfer rotary member before the tip end of the transfer member enters a nip area. A bias power supply has a polarity inverting function of, during a period from a timing when the tip end of the transfer member is brought into contact with the transfer rotary member by the transfer member transporting section, to that when the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is identical with that of a toner, to the transfer rotary member, and after the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is opposite to that of the toner, to the transfer rotary member.

Abstract: The developing apparatus includes a developer bearing member, a developer removing-feeding member and a circulating member, wherein the developer circulating member has a push-in amount to the removing-feeding member equal to or larger than a push-in amount of the developer circulating member to the developer removing-feeding member, thereby preventing toner fusion or generation of uncharged developer by a deterioration of the developer, and realizing stable development over a prolonged period.

Abstract: A method and apparatus for applying a predetermined load to a roller in a printer and/or copier apparatus comprises supporting a first member relative to a frame, the first member including a driver element; advancing the driver element under a first force to establish a spring force in a spring; the driver element being stopped by a stop member to isolate any variability in the first force from affecting the spring force; providing a force receiving surface secured to said roller; engaging the force receiving surface with a second member, the second member being connected to the spring so as to provide a loading force to the roller.