Abstract: An optical receiver circuit is disclosed in which a number of electrical signals are processed to extract data encoded therein. The electrical signals may be compared during the process to selectively remove one or more waveforms from one or more corresponding electrical signals. Various data signals, each including one or more waveforms, may then be processed to extract the encoded data. The optical receiver circuit reduces, or eliminates, electrical offsets which may be present in one or more of the electrical signals to reduce corresponding errors in the encoded data signals.

Abstract: A trans-impedance amplifier (TIA) with an adjustable bandwidth is disclosed. The TIA of the present invention includes the amplifying stage and the emitter follower stage arranged in the downstream of the amplifying stage. The transistor in the amplifying stage includes a diode in the emitter thereof to provide a substantial emitter level to the transistor. This diode is biased by another current source with a variable function. The operating point of the diode, in particular, the differential resistance thereof, is variable by the current source, which adjusts the bandwidth of the TIA without affecting the phase characteristic of the TIA.

Abstract: The present invention provides a detection unit that detects, regarding a toner supply device loaded into an installation space of an apparatus main body, a type of the toner supply device or detects improper loading of the toner supply device and a notification unit that notifies loading of the toner supply device of a wrong type or improper loading of the toner supply device based on a result of detection by the detection unit.

Abstract: An image forming apparatus includes a first unit including means contributable to image formation; a second unit constituting a pair with the first unit and including means contributable to the image formation; a detecting device for detecting a degree of use of each of the first unit and the second unit, wherein limits of usability are predetermined for the first unit and the second unit, respectively; and a control device capable of outputting information signals for notifying states near the limits of usability on the basis of preset thresholds of degrees of use, respectively, wherein a number of capable image formations from an output of the signal indicating the near state for the first unit to the limit of usability of the first unit is larger than a number of capable image formations from an output of the signal indicating the near state for said second unit to the limit of usability of the second unit, and wherein the control device outputs the signal for the second unit when the degree of the second

Abstract: An imaging apparatus includes a toner cartridge within a housing having a rotatable shaft, a cam rotatably mounted on the shaft, an optical sensor mounted on the housing having an emitter and a receiver forming an optical path therebetween, and a flag mounted on the housing having a first arm and a second arm. The optical sensor has an output that changes when the optical path changes from blocked to unblocked and from unblocked to blocked. The flag has a home position where the first arm is disposed in the rotational path of the cam and the second arm either blocks the optical path or unblocks the optical path. Rotation of the rotatable shaft causes the cam to engage and disengage the first arm causing the second arm to change from blocking the optical path to unblocking the optical path or vice versa.

Abstract: The present invention provides a fixing device that can interrupt power supply to the resistive heat layer more reliably than the conventional technology, for example, at occurrence of abnormality. Electrodes 52a and 52b are provided on a circumferential surface of a fixing roller that includes a resistive heat layer that generates heat by receiving power supply, and power is supplied to the resistive heat layer when power supplying electrodes 54a and 54b that are electrically connected to an electric power source 55 are slidingly in contact with the electrodes 52a and 52b. An insulating tape 522a is attached on the electrode 52a, and the drive controller 59 rotates a motor 58 until the electrode 52a and the insulating tape 522a are in contact with each other, so that power supply to the resistive heat layer is interrupted.

Abstract: An image forming apparatus according to an embodiment includes a solar panel, an electric storage unit which is supplied with electric power from the solar panel and a commercial power supply and stores electricity, a power supply disconnection detecting unit which detects power supply disconnection from the commercial power supply, and a maintenance control unit for power supply disconnection which carries out maintenance control using stored electricity from the solar panel if the power supply disconnection from the commercial power supply is detected by the power supply disconnection detecting unit.

Abstract: An image forming apparatus includes: a latent image forming unit forming a latent image; a transfer body on which a reference index for setting an output start time point of image data is formed; a detecting unit facing the reference index and outputting a detection signal changing in accordance with passing of the reference index; a measuring unit measuring change duration time; and a controller controlling the output start time point with the detection signal. The controller starts a first period during which change of the detection signal is ignored, according to first change of the detection signal, starts a second period after the first period, regards change of the detection signal occurring first in the second period as a reference of the output start time point if the change duration time is longer than a predetermined period, and ignores change of the detection signal after the change occurring first.

Abstract: An image forming apparatus including an image bearing member; a developing device for developing with toner an electrostatic latent image formed on the image bearing member; a humidity sensor for providing information on ambient humidity of said image forming apparatus; and a controller for controlling a parameter on a density of an image to be formed on a recording material on the basis of pieces of the information provided by the humidity sensor at different times.

Abstract: An image forming apparatus for printing an image on a medium, comprising: a first image carrier; a second image carrier disposed downstream of the first image carrier in a traveling direction of the medium; a first charging member configured to charge the first image carrier; a second charging member configured to charge the second image carrier; and a control unit configured to execute a monochrome printing mode in which a monochromic image is formed on the medium using the first image carrier and the first charging member and a color printing mode in which a color image is formed on the medium using the second image carrier and the second charging member. In the monochrome printing mode, the control unit makes an absolute value of an electric surface potential of the second image carrier larger than an absolute value of the electric surface potential of the first image carrier.

Abstract: One aspect of the present invention provides an information processing apparatus for determining a height of a toner image formed on a carrier, the apparatus comprising: a control unit configured to control an amount of irradiation light based on whether laser light irradiated by an irradiation unit is irradiated onto the toner image; an acquisition unit configured to acquire an image obtained by capturing reflected light of the laser light irradiated by the irradiation unit; and a determination unit configured to determine the height of the toner image based on the acquired image.

Abstract: A multifunction peripheral includes: development units of respective colors; an intermediate transfer belt; a transfer roller; a movement mechanism that moves the intermediate transfer belt in a direction of coming in contact with and separating from a magenta development unit and the like; a concentration sensor; a control part that causes the magenta development unit and the transfer roller to form a toner pattern on the intermediate transfer belt; and a determination unit that determines that the pressing state of the magenta development unit and the like and the intermediate transfer belt is normal when the toner pattern concentration detected by the concentration sensor after the toner pattern is transferred to the intermediate transfer belt has reached a predetermined concentration value.

Abstract: An image forming apparatus is capable of more directly solving a problem of unevenly formed line images. The image forming apparatus includes a rotatable photosensitive member, a light emission unit configured to emit a laser beam based on image information, and a transfer unit configured to transfer a toner image developed on the photosensitive member. The image forming apparatus acquires variable speed information, which indicates a variable rotation speed of the photosensitive member. In addition, the image forming apparatus executes image position correction on the image information based on the acquired variable speed information.

Abstract: A development method according to an embodiment includes exposing a photosensitive film formed on a substrate at a predetermined exposure amount, carrying out a first development process that develops the exposed photosensitive film at a predetermined first development condition so as to leave the photosensitive film, obtaining a sensitivity information of the photosensitive film from a film thickness reduction of the photosensitive film developed by the first development process and the exposure amount, predicting pattern dimensions of multiple types of patterns to be formed when a second development process is carried out following the first development process from the sensitivity information, and determining a first acceptable range of a development condition in the second development process, determining a second acceptable range of the development condition in the second development process from the first acceptable range and a variation amount of the pattern dimension after the development process betw

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; a rotatable intermediary transfer member onto which the toner image is to be primary-transferred from the image bearing member; a contact member movable toward and away from the intermediary transfer member; a voltage applying unit for applying a voltage to the contact member; a current detecting circuit for detecting a current passing through the contact member to which the voltage is applied by the voltage applying unit; and a control portion for effecting control so that the contact member is contacted to or separated from the intermediary transfer member.

Abstract: An image forming apparatus including: an image bearing member for bearing a toner image; a transfer section, which is pressed against, and is separated from, the image bearing member, for transferring a toner image on the image bearing member onto a recording medium when being pressed against the image bearing member, a transfer section drive section for driving the transfer section to rotate; and a control section configured to control the transfer section drive section to carry out constant speed control and constant torque control, to drive said transfer section to rotate at a constant speed, and at a constant torque, respectively, wherein the control section carries out the constant torque control while the transfer section is pressed against the image bearing member, in accordance with a drive torque detected when the constant speed control is carried out while the transfer section is separated from the image bearing member.

Abstract: A fixing device includes a heat roller and an opposing component. The heat roller extends in an axial direction and includes a cylindrical-shaped roller section and a coil. The heat roller section has an inner circumferential surface and an outer circumferential surface. The coil is spirally wound along the inner circumferential surface and including a first portion and a second portion other than the first portion, the first portion being configured of such a number of turns of the coil, the number being a natural number greater than zero, the first portion having a first coil pitch length in the axial direction, and the second portion being configured of at least one turn of the coil and having a second coil pitch length in the axial direction greater than the first coil pitch length. The opposing component confronts the outer circumferential surface of the roller section and is exclusively superposed with an entire first portion via the roller section.

Abstract: A fixation device includes a fixation member including a heating member, a pressure-application member press-contacting the fixation member forming a nip portion, an exciting coil induction-heating the heating member, a first temperature detection unit detecting a first temperature of the pressure-application member or a first ambient temperature of the fixation member, a second temperature detection unit detecting a second temperature of the fixation member, and a control unit selecting a temperature control mode or power control mode controlling power to the exciting coil. When the first temperature exceeds a first threshold temperature or the first ambient temperature exceeds a first ambient threshold temperature, the control unit selects the temperature control mode, and while the first temperature is equal to or lower than the first threshold temperature or the first ambient temperature is equal to or lower than the first ambient threshold temperature, the control unit selects the power control mode.

Abstract: An image forming apparatus includes a control unit arranged to control an image forming unit so as to form images based on image information and to form maintenance images for maintaining the image forming unit. The control unit is arranged to control the image forming unit so as to form images on the second side of the sheet after forming images on the first side of the sheet, and so as to form the maintenance images on the second side at positions such that the maintenance images do not overlap with the images based on the image information formed on the first side.

Abstract: A high-voltage power supply device comprises: a piezoelectric transformer; a driving unit of the piezoelectric transformer; a detection unit configured to detect the output of the piezoelectric transformer; and a control unit configured to control the output of the piezoelectric transformer by giving a driving signal to the driving unit so that the output detected by the detection unit reaches a target value, wherein the control unit changes a frequency of the driving signal without changing a duty of the driving signal so as to set the frequency of the driving signal such that the output falls within a predetermined range including the target value, and after setting the frequency for the output within the predetermined range, changes the duty of the driving signal so that the output reaches the target value.

Abstract: An image foaming apparatus includes an image bearing member, a transfer unit, and a pressing mechanism. The image bearing member bears a toner image. The transfer unit is disposed opposite the image bearing member and is swingably and detachably held within a main body of the image forming apparatus. The transfer unit includes a transfer member and a power receiving electrode. The transfer member is disposed opposite the image bearing member, to contact the image bearing member to form a transfer nip therebetween and transfer the toner image on the image bearing member onto a recording medium in the transfer nip. The power receiving electrode receives power from the main body of the image forming apparatus. The pressing mechanism presses the transfer unit against the image bearing member and includes a power supply electrode that contacts the power receiving electrode of the transfer unit to supply power thereto.

Abstract: A current resonance power supply includes a transformer having a primary winding and a secondary winding, two switching elements connected to one end of the primary winding of the transformer and arranged in series, a resonance capacitor connected to the other end of the primary winding, and a voltage detection unit connected between the one end of the primary winding and the two switching elements and configured to detect that AC voltage input to a primary side of the transformer becomes lower, wherein operations of the switching elements are controlled based on a detection result of the voltage detection unit.

Abstract: The image forming apparatus includes an image bearing member, a transfer member, a power supply unit including a first voltage generation circuit and a control unit that controls the power supply unit, wherein in the case where a voltage whose magnitude cannot be output by the first voltage generation circuit is output from the power supply unit to the transfer member in spite of driving the first piezoelectric transformer at the drive frequency in the first drive frequency area, the control unit controls the power supply unit to output the voltage to the transfer member by superposing a voltage output from the first voltage generation circuit by driving the first piezoelectric transformer at a frequency in the first drive frequency area with a voltage output from the second voltage generation circuit by driving the second piezoelectric transformer at a frequency in the second drive frequency area.

Abstract: An upper conveyance guide is provided at an apparatus main body. A guide surface of a lower conveyance guide is provided facing a guide surface of the upper conveyance guide, and can be drawn out in the direction intersecting the sheet conveyance direction with respect to the apparatus main body. A cleaning unit is provided on the back side in the drawing-out direction of the lower conveyance guide, moves together with the lower conveyance guide when the lower conveyance guide is drawn out from the apparatus main body, and cleans the guide surface of the upper conveyance guide.

Abstract: An image forming apparatus is provided. The image forming apparatus includes a chassis having an opening, a cover, photosensitive members, an intermediate transfer belt, a primary-transfer member, a secondary-transfer roller, a cleaner device, an external-sheet inlet, a waste toner container, a connector, and a conveying roller, which is arranged within the feeding path to feed the recording sheet inserted through the external-sheet inlet in the feeding path. The conveying roller is mounted on the waste toner container and removable from the chassis along with the waste toner container.

Abstract: An image forming apparatus is provided. The image forming apparatus includes a chassis, a cover, photosensitive members, an intermediate transfer belt, primary-transfer members, a secondary-transfer roller, a first feed roller, a cleaner device, a waste toner container, which is movable along the predetermined direction to be removably installed in the chassis through a first opening and stores residual toner, a connector, a first feeding path, a second feeding path being a path for a recording sheet inserted through a sheet inlet and includes a sheet guide to guide the recording sheet, and a second feed roller. The second feed roller is movable along with at least a part of the sheet guide. The waste toner container is movable through space, which is occupied by the second feed roller in an upper position, and the first opening when the second feed roller is in a lower position.

Abstract: An image forming apparatus is provided. The image forming apparatus includes a chassis having an opening, a cover, photosensitive members, an intermediate transfer belt, a primary-transfer member, a secondary-transfer roller, a cleaner device, a waste toner container, which is movable along a predetermined direction to be removably installed in the chassis through the opening and stores residual toner, a connector, and a feed roller, which is arranged within the feeding path to feed the recording sheet in the feeding path. The feed roller is arranged in a position to at least partially fall within a vertical range of the waste toner container and to be aligned with the waste toner container along an axial direction of the second feed roller.

Abstract: A toner container system includes a reservoir for containing toner having a rotatable member positioned within an opening through the reservoir and a skiving seal for blocking toner from entering a gap between the opening and the rotatable member. The skiving seal is positioned along the length of the rotatable member and is adhesively affixed adjacent to the rotatable member along the gap in the skiving direction of rotation of the rotatable member. The skiving seal includes a flexible sheet having a length corresponding to the length of the gap and a tubular portion adjacent to the gap formed by folding the flexible sheet over itself from an edge extending along the length of the flexible sheet, without creasing the fold, and adhering a portion of the folded portion of the flexible sheet to the surface of the flexible sheet along the length of the flexible sheet.

Abstract: A stopper for plugging a developer filling port includes a stopper main body and a lock member engageable with the stopper main body. The stopper main body is configured to be fitted to the filling port and shaped like a tube with a bottom. The lock member has a rigidity greater than that of the stopper main body, the lock member engaged with the stopper main body serves to restrict deformation of the stopper main body. A developing device for use in an image forming apparatus includes the stopper configured as described above to be fitted to its developer filling port.

Abstract: Remanufactured laser printer toner cartridges and methods of manufacture by which predetermined structures internal to the toner hopper section are removed preferably by a robotic laser cutter, a volume increasing cap is provided for the modified toner hopper section and the cartridge is re-assembled to yield a remanufactured toner cartridge that has a capacity to store toner that is significantly increased in comparison to the storage capacity of the OEM toner cartridge.

Abstract: A remanufactured laser printer toner cartridge has a used magnetic roller section chassis and a used toner hopper assembly, both obtained by splitting toner cartridges along ultrasonic welds. The used magnetic roller section chassis and the used toner hopper assembly are joined with a resilient adhesive along the remnants of the ultrasonic welds. The remanufactured cartridge may include a new pull seal to close the opening between the toner hopper assembly and magnetic roller section chassis.

Abstract: An electrophotographic photosensitive member is provided in which both a long-term potential variation and a short-term potential variation are suppressed, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. The intermediate layer of the electrophotographic photosensitive member includes an organic resin and rutile-type titanium oxide crystal particles which contain tin and have an average primary particle diameter of 3 nm or more and 9 nm or less.

Abstract: A color electrophotographic image forming apparatus in which a cartridge tray supporting a plurality of cartridges is movable through a plurality of opening portions to respective outside positions outside an apparatus main body. In the color electrophotographic image forming apparatus, the plurality of cartridges are removably mounted to the apparatus main body to form an image on a recording medium. The color electrophotographic image forming apparatus includes: a cartridge tray (26), which is movable, while supporting the plurality of cartridges, between an inside position positioned inside the apparatus main body and the outside positions; a plurality of opening portions (31, 92) provided in the apparatus main body, through which the cartridge tray (26) is movable between the inside position and the outside positions; and doors (28, 94) for opening and closing the plurality of opening portions (31, 92).

Abstract: A drum unit is provided, which includes a frame configured such that a development cartridge including a pressed portion is detachably attached thereto, and a pressing member. The development cartridge is movable between a pressed state where the pressed portion is pressed by the pressing member when attached to the frame and a released state where the pressed portion is released from pressing of the pressing member when the development cartridge is attached to the frame. The pressing member includes a pressing section that contacts and presses the pressed portion when the development cartridge is in the pressed state, and a restriction section configured to, when the development cartridge is in the pressing state, restrict movement of the pressed portion in a released direction, in which the pressed portion moves when the development cartridge moves from the pressing state to the released state.

Abstract: An image forming apparatus includes a main assembly; a door member which supports one of roller members constituting a feeding nip for a recording material and which is rotatable about an axis parallel with said roller members in a sidewise direction of said main assembly to open said feeding nip; a pair of urging mechanisms which are provided at opposite end portions of said door member with respect to a front-rear direction of said main assembly and which fix said door member to said main assembly so as to be capable of opening and closing said door member, said urging mechanism urging said door member toward said main assembly in a state that said door member is closed; and an operating member provided with a grip for manual opening of said door member, said grip being disposed in a position nearer to a front side than a center portion position of said door member with respect to the front-rear direction, and said operating member being rotatably supported in a position nearer to a rear side than a center

Abstract: An image forming apparatus includes a plurality of photoconductive drums, each photoconductive drum transferring a portion of a toner image to an intermediate transfer member. The photoconductive drums are individually rotated to a printing speed such that a downstream photoconductive drum starts rotating prior to an adjacent upstream photoconductive drum starts image transfer. Similarly, an upstream photoconductive drum starts deceleration when its following downstream station has transferred image.

Abstract: A rotary drive device to drive a rotary body included in an image forming apparatus. The rotary drive device includes a drive source and a planetary gear mechanism to control torque from the drive source. The planetary gear mechanism includes a sun gear rotated by the torque, an annular gear coaxial to the sun gear and having inward-facing teeth, multiple planetary gears provided within the annular gear, and a carrier rotatable coaxially to the sun gear and the annular gear to rotatably support the multiple planetary gears. The annular gear is formed by injecting molten resin into a mold having a cylindrical cavity with teeth shapes along an inner circumference of the cavity from multiple pin gates provided to the mold at equal intervals along a circumference of the cavity. A number of pin gates is a non-integer multiple of a number of planetary gears.

Abstract: A driving mechanism includes: a looped metallic transmission belt; a first shaft member; a second shaft member; and a pulley that is connected to the second shaft member so as to be rotatable about a second rotational axis, in which the first shaft member includes: a rotatably supported portion that is disposed at one end; and an extended portion that is disposed at another end so as to be continuous with the rotatably supported portion, in which a portion between the contact portion and the rotatably supported portion is flexurally deformed, the extended portion being rotatable about a diagonal rotational axis that is inclined at a predetermined angle relative to the first rotational axis, and the pulley includes a inclined outer surface that is inclined, such that a portion that is most separated from the first shaft member is substantially parallel with the extended portion.

Abstract: An image forming apparatus includes: a photoconductor that rotates about a first rotation axis; and a charging roller that rotates about a second rotation axis which is parallel to the first rotation axis, wherein the charging roller includes a conductive roller portion that extends in parallel with the first rotation axis and contains an ion-conductive agent, a flange portion that is provided on an outer peripheral surface of the conductive roller portion further to the outside than an image forming area of the photoconductor in the second rotation axis direction so as to protrude outward from the outer peripheral surface in the radial direction of the conductive roller portion into a flange shape, and an insulating elastic layer that coats the outer peripheral surface of the flange portion and has an elasticity higher than that of a photoconductive surface of the photoconductor.

Abstract: This invention provides a surface-emitting laser that can prevent delamination at the interface of a selective oxidation layer and a spacer layer, while suppressing any rise of voltage, to improve the reliability of operation.

Abstract: A developer stirring member for stirring a developer in a developer accommodating portion, the developer stirring member includes a supporting shaft; a sheet-like member for stirring the developer, the sheet-like member having a first lateral end which is a free end and having a second lateral end which is fixed on the supporting shaft, wherein the sheet-like member is waved at the second lateral end, and waving is greater in the second lateral end than in the first lateral end.

Abstract: A toner supplying device includes a toner storing portion for storing toner; a toner feeding path in which the toner fed from the toner storing portion is to be fed; a toner feeding member for feeding the toner in the toner feeding path; and an executing portion for executing an operation in a filling mode in which the toner is filled in the toner feeding path by intermittently driving the toner feeding member in a preparatory period before image formation.

Abstract: A toner cartridge converting device is provided with a driving module to change gaps between a photoreceptor drum and respective toner cartridges using a positioning groove formed in a radial direction of the photoreceptor drum. Each fixing rod of the toner cartridges can slide into the positioning groove and slide out of the positioning groove with following the displacement of the groove, so that the converting operation to the toner cartridges can be finished. Due to the configuration space required by the driving module is smaller, and the quantity of elements is less than the conventional driving unit and easy in repair and maintenance, so that the structure of the driving module is simplified and the repair cost is reduced.

Abstract: A developer supply device is provided, which includes a developer retrieving member disposed to face a developer holding surface of a developer holding member across a predetermined distance in a position downstream relative to a developer supply position where the developer holding member faces an intended device to be supplied with development agent in a direction perpendicular to a main scanning direction parallel to an axial direction of the developer holding member. The developer retrieving member is driven to rotate around an axis parallel to the main scanning direction and configured to retrieve the development agent from the developer holding surface under a retrieving electric field that is generated when a retrieving voltage is applied between the developer retrieving member and the developer holding member.

Abstract: A cam driving mechanism has: a cam; a motor which drives the cam; a gear train which transmits, while reducing the speed of, the output of the motor to the cam; a pulse disk which is formed integrally with a gear coupled in the gear train and in which a plurality of slits are formed at equal intervals; a home position detecting member which is arranged coaxially with the pulse disk so as to be rotatable independently thereof and which, by meshing with another gear coupled in the gear train, rotates at a lower rotation speed than the pulse disk; and a cam position detecting sensor which has a detecting portion including a light-emitting portion and a light-receiving portion, the cam position detecting sensor detecting the amount of driving of the cam based on the number of slits of the pulse disk that have passed through the detecting portion, the cam position detecting sensor detecting the home position of the cam based on the timing with which the home position detecting member shields the detecting portion.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; a toner image forming portion for forming a toner image on the image bearing member; a rotatable belt member, stretched by a plurality of stretching members, for carrying and conveying a recording material; a transfer member for transferring the toner image from the image bearing member onto the recording material carried on the belt member by pressing the belt member against the image bearing member; a bias applying portion for applying to the transfer member a transfer bias for transferring the toner image from the image bearing member onto the recording material; a push-up member for locally pushing up the belt member from an inner surface side of the belt member, in a direction perpendicular to a recording material conveyance direction, at a downstream-side position of the transfer member with respect to the recording material conveyance direction; and an execution portion for executing an operation in a mode in which t

Abstract: An induction heating type fusing device and an image forming apparatus including the fusing device. The fusing device includes a magnetic flux generator and a compressing roller outside a fusing belt, first and second fusing rollers and a nip guide inside the fusing belt. The compressing roller compresses against the first and second fusing rollers and the nip guide to form nips, while the fusing belt is disposed between the compressing roller and the first and second fusing rollers and the nip guide.

Abstract: A novel fixing device including a fixing member to fix a toner image on a sheet by application of heat and pressure and a pressing member to press the sheet against the fixing member. The pressing member is rotatable. A height difference is circumferentially provided to the pressing member, and is tapered from an end portion toward a portion contacting an edge of a small-size sheet. The pressing member has a greater hardness than the fixing member.

Abstract: A fixing device for thermally fixing an unfixed image onto a recording sheet by causing the sheet to pass through a fixing nip. The fixing device includes: heat belt formed in an endless shape and provided with a resistance heat layer; first pressure member provided inside a running path of the heat belt; and second pressure member pressing the first pressure member from over the running path to form the fixing nip. At least one of the first and second pressure members is rotating body. The heat belt has a pressure-receiving area and two non-pressure areas. The pressure-receiving area receives pressures from both the first and second pressure members. The non-pressure areas have been arranged at outside of the pressure-receiving area in an axis direction of the rotating body. Two ring-like electrodes have been formed on circumferential surfaces of the non-pressure areas and are used to supply power to the resistance heat layer.

Abstract: A fixing device includes a heat roller and a heater. The heat roller extends in an axial direction and includes a cylindrical-shaped roller section and a coil, the roller section having an inner peripheral surface defining an internal space therewithin and the coil being wound along the inner peripheral surface, the heat roller being configured of a plurality of zones in the axial direction, the plurality of zones including a low zone whose heat capacity is less than a predetermined value and a high zone whose heat capacity is not less than the predetermined value. The heater is disposed within the internal space of the roller section and has a heating wire configured to generate heat, the heating wire having at least a first portion which is in confrontation with the high zone and a second portion which is in confrontation with the low zone, and the heating wire being configured such that the first portion has an amount of heat generation greater than an amount of heat generation at the second portion.