Abstract: A fixing member is supported so as to be displaceable in a crossing direction that crosses a sheet conveying direction. A pressure member rotationally drives the fixing member by being rotationally driven. A motor rotationally drives the pressure member. A biasing mechanism elastically biases the fixing member toward the pressure member. A sheet detection portion detects a sheet at a first position and a second position. The first position is a position between a mechanism that feeds the sheet to a fixing position and the fixing position in the conveyance path. The second position is a position between the fixing position and a mechanism that takes over conveyance of the sheet from the fixing device. A control device times a time required for detection results from the sheet detection portion to show a predetermined change, and controls a rotational speed of the motor according to the timed time.

Abstract: An image forming apparatus includes a fixing unit, a switching element, and a controller. The controller controls the switching element on a half-cycle basis of an alternating current. A period in which the electric power is supplied to the heater within a period of a half-cycle of the alternating current is divided into at least one first power supply period and a second power supply period longer than one first power supply period. A length of a sum of the at least one first power supply period is a length from 1/6000 to 1/40 of one cycle of the alternating current. A sum of electric power supplied in the at least one first power supply period and electric power supplied in the second power supply period is determined depending on a difference between a temperature and a target temperature of the fixing unit.

Abstract: A fixing apparatus including a heat generating element having a first area, a second area, and a third area, the first area being located on an end portion side in an orthogonal direction orthogonal to a conveyance direction of a recording material and having a first heat generation amount per unit length in the orthogonal direction, the second area being located on an inner side than the first area in the orthogonal direction and having a second heat generation amount per unit length in the orthogonal direction, the third area being located on the inner side than the second area in the orthogonal direction and having a third heat generation amount per unit length in the orthogonal direction. The second heat generation amount is larger than the third heat generation amount, and the third heat generation amount is larger than the first heat generation amount.

Abstract: In an image forming apparatus, upon receipt of a printing instruction, a controller starts rotation of a heating member, starts rotation of a photoconductor drum when a standby time has elapsed from a time of the start of the rotation of the heating member, starts conveyance of a sheet after the start of the rotation of the photoconductor drum, and forms a toner image on the sheet after the start of the conveyance of the sheet. The controller is configured to be operated in one of selectable modes including a multicolor mode in which a toner image is formed using both of toner of a first color and a second color and a monochrome mode in which a toner image is formed using toner of the second color only. The standby time adopted in the monochrome mode is longer than the standby time adopted in the multicolor mode.

Abstract: A fixing device includes a fixing member, a pressurizing member, a charging portion, and a control portion. The fixing member rotates while being heated. The pressurizing member forms a nip portion between itself and a surface of the fixing member in such a way as to hold a sheet therebetween and conveys the sheet by rotating together with the fixing member, wherein an image of toner has been formed on the sheet. The charging portion electrically charges the surface of the fixing member to a polarity that is same as a charging polarity of the toner by supplying a charging current to a pair of electrodes that is disposed to face the surface of the fixing member. The control portion increases the charging current as time passes during a control time period that corresponds to a time period for which the sheet passes through the nip portion.

Abstract: In one embodiment, an image forming apparatus includes a fixing device with a heating element to heat a sheet. A controller is configured to control electric power supplied to the heating element based on a prior use metric. The controller reduces the electric power supplied to the heating element during a startup period if an electric power level supplied from a power supply is equal to or greater than a threshold value and the prior use metric is equal to or greater than a reference value.

Abstract: In an image forming device, a first fixing member has a roller. A second fixing member has a belt to form a nip together with the first fixing member. A first motor drives the roller. A pressure modifying mechanism modifies a nip pressure at the nip to selected one of a first nip pressure and a second nip pressure smaller than the first nip pressure. A controller starts driving the first motor to drive the roller in a case where a print command is received in a state that the nip pressure is the second nip pressure. The controller modifies the nip pressure from the second nip pressure to the first nip pressure after the driving is performed and fixes the developer image on the sheet in a state that the nip pressure is the first nip pressure.

Abstract: An image forming apparatus includes an image forming unit configured to form an image; a transferring unit configured to transfer the image formed by the image forming unit on a recording material; a fixing unit having a fixing heater, the fixing heater being configured to generate heat with electric power supplied from a commercial power source, and the fixing unit being configured to fix the image on the recording material by heating the recording material on which the image is transferred with the heat generated by the fixing heater; a memory configured to store resistance information representing a resistance value of the fixing heater; a zero-cross detection unit configured to detect a zero-cross timing of an AC voltage supplied from the commercial power source, and a voltage detection unit configured to detect a voltage value of AC voltage.

Abstract: An image forming apparatus, having a photosensitive drum, a developing roller movable between a contacting position, in which the developing roller contacts the photosensitive drum, and a separated position, in which the developing roller is separated from the photosensitive drum, a moving mechanism to move the developing roller between the contacting position and the separated position, a fuser including a heating member and a pressing member to nip a sheet at a position between the heating member and the pressing member, a nipping-force adjuster to switch a nipping force in the fuser between a first nipping force and a second nipping force being greater than the first nipping force, a motor, and a driving-force transmitter to transmit a driving force from the motor to the developing roller, is provided. The driving-force transmitter transmits the driving force further to the moving mechanism and the nipping-force adjuster.

Abstract: A heat generating roller includes a base member made of metal, a heat generating portion made of a material that generates heat when energized, and an insulating portion provided between the base member and the heat generating portion and that electrically insulates the base member and the heat generating portion from each other, the insulating portion being made of poly-ether-ether-ketone resin.

Abstract: An image forming device includes a transfer unit that transfers a toner image onto a recording medium that has first and second surfaces and is conveyed in a conveyance direction; a main heating unit arranged downstream of the transfer unit in the conveyance direction, and which contacts and heats the recording medium and fixes the toner image onto the recording medium; a reversing unit that reverses front and back of the recording medium having a first toner image fixed onto the first surface; and a preheating unit arranged between the transfer and main heating units in the conveyance direction and that heats the recording medium having a second toner image transferred onto the second surface. The preheating unit heats the recording medium so that a temperature of the first surface is lower than a softening point of a toner before the recording medium is heated by the main heating unit.

Abstract: A heating device includes a rotator, an opposed rotator configured to contact the rotator to form a nip, a heater configured to heat the rotator, and a plurality of pressing devices. The heater includes a first portion and a second portion. The second portion of the heater generates a smaller amount of heat than the first portion of the heater. The pressing devices are arranged in a longitudinal direction of the heater and each configured to press at least one of the rotator and the opposed rotator and cause the rotator and the opposed rotator to press each other. The pressing devices include a first pressing device corresponding to the first portion of the heater and a second pressing device corresponding to the second portion of the heater, and the first pressing device generates a smaller pressing force than the second pressing device.

Abstract: An image forming device includes a sheet feeding device, an image forming part, a fixing device, a conveyance path, a first sensor and a second sensor. The first sensor is disposed on the conveyance path on a downstream side of the fixing device in the conveyance direction and detects the sheet passed along the conveyance path. The second sensor is disposed on the conveyance path on an upstream side of the fixing device in a conveyance direction and detects the sheet passed along the conveyance path. The fixing device stops a driving of a heating source and stops a rotation of a fixing belt when the first sensor does not detect the sheet passing properly. The fixing device stops the driving of the heating source and stops the rotation of the fixing belt after a predetermined period when the second sensor do not detect the sheet passing properly.

Abstract: An image forming apparatus according to the present invention includes a first conveyance member, a second conveyance member, and a controller. The first conveyance member and the second conveyance member convey a continuous sheet. The controller determines whether a second conveyance speed which is a conveyance speed of the continuous sheet conveyed by the first conveyance member and the second conveyance member can be detected normally on the basis of a first conveyance speed which is a conveyance speed of the continuous sheet conveyed by the first conveyance member.

Abstract: A contact-separation mechanism includes a cam to rotate to move a contact-separation member to and from a counterpart member, a detection target to rotate together with the cam, and a detector to detect presence or absence of the detection target in a detection area of the detector, and circuitry. The cam has a reference range. The circuitry issues a rotation stop instruction of the cam after a target time elapses from passing of the reference range of the detection target through the detection area, and sets the target time based on a duration of an immediately preceding passing of the reference range through the detection area.

Abstract: A fixing unit includes a changing portion configured to change a state of a first rotary member and a second rotary member between a first pressurization state and a second pressurization state. A control portion is configured to control the driving source and the changing unit and capable of performing first control that causes the driving source to rotate the first rotary member and then stop the first rotary member, while continuing the first pressurization state from a last image forming operation, and second control that causes the changing portion to change the state of the first rotary member and the second rotary member from the first pressurization state to the second pressurization state.

Abstract: A heating device includes: a rotating body; a heating body as defined herein; and a contact mechanism, in a non-existence state where a material to be heated does not exist between the rotating body and the heating body after the material to be heated passes between the rotating body and the heating body, configured to cause the rotating body to be in contact with the heating body at a central portion of the rotating body in a rotation axis direction of the rotating body, so that an area of the rotating body in contact with the heating body is smaller at each of both end portions of the rotating body than at the central portion of the rotating body in the rotation axis direction, or configured to switch the rotating body between a first contact state and a second contact state as defined herein.

Abstract: An image forming apparatus is provided. The image forming apparatus according to an example includes a print engine including a fuser, a power supply apparatus to selectively provide AC power to the fuser, and a processor to control the power supply apparatus to selectively provide AC power to the fuser, wherein the processor, based on an operation mode of the image forming apparatus being a print mode, performs waveform number control of the AC power provided to the fuser, and, based on the operation mode of the image forming apparatus being an operation mode except for the print mode, performs phase control of the AC power provided to the fuser.

Abstract: A fixing apparatus includes a fixing belt, a pressing roller configured to form a nip by pressing the fixing belt and rotate the fixing belt, a bush configured to guide an edge of the fixing belt, and a meandering adjustment member configured to move a rotation shaft of the pressing roller in a direction perpendicular to an axis direction of the pressing roller. The fixing apparatus can be provided to an image forming apparatus.

Abstract: A pressure device includes: a first pressure element; a second pressure element that is disposed so as to oppose the first pressure element and that applies pressure to a medium nipped between the first pressure element and the second pressure element; a moving device that moves the second pressure element toward and away from the first pressure element, between a contact position and a retracted position; an urging member that urges the first pressure element toward the second pressure element when the second pressure element is located at the contact position; and a driving device that applies a driving force to the second pressure element, thus allowing the first pressure element to rotate in a driven manner when the second pressure element is located at the contact position.

Abstract: A heating device includes at least one heat-generating member that generates heat by being supplied with power supplied by a shared power source and a controller that performs control in such a manner that, when the shared power source starts supplying power to the heat-generating member, a rated power is supplied to the heat-generating member after power that is 33% output or 67% output of the rated power has been supplied to the heat-generating member.

Abstract: A fixing device includes: a rotary body; a pressure body; a frame supporting the rotary body; and a pressure varying mechanism for providing a nip pressure to a nip region formed between the rotary body and the pressure body. The pressure varying mechanism includes a first spring and a second spring for urging one of the rotary body and the pressure body. The first spring applies a first urging force, and the second spring applies a second urging force acting in an opposite direction from the first urging force. The pressure varying mechanism can vary the nip pressure between a first nip pressure and a second nip pressure smaller than the first nip pressure. The nip pressure becomes the first nip pressure while only the first urging force is applied, and becomes the second nip pressure while both of the first urging force and the second urging force are applied.

Abstract: A heating device includes a belt, a heater that is in contact with an inner surface of the belt and divided into heater blocks in a width direction thereof, a pressing member that presses a sheet against the belt, a temperature sensor disposed on each of a number of the heater blocks that is at least one-half of the total number thereof, and a processor configured to select one or more of the heater blocks based on a width of the sheet, and select one or more temperature sensors disposed on one or more of the selected heater blocks having the non-paper passing region and control electric power supplied to said one or more of the selected heater blocks to protect against an excessive temperature rise in the non-paper passing region based on temperatures detected by the temperature sensors.

Abstract: A heater includes a plurality of resistive heat generators electrically connected to each other in parallel. A power supply supplies power to the resistive heat generators. An electric current detector detects an electric current that flows through the resistive heat generators. A voltage detector detects a voltage applied to the resistive heat generators. An electric current controller controls the electric current that flows through the resistive heat generators based on the electric current detected by the electric current detector and the voltage detected by the voltage detector. The electric current detector detects the electric current in a state in which, after the power supply starts supplying the power to the resistive heat generators, a waveform of an alternating current supplied to the resistive heat generators remains constant for a predetermined time period or longer taken for the electric current detector to detect the electric current.

Abstract: An image forming apparatus includes an image former which forms an image on a recording medium, a pressure member, a fixing member which is pressed against the pressure member to form a nip portion and comes into contact with the image formed on the recording medium conveyed at the nip portion, and a hardware processor. The hardware processor causes one member, either the pressure member or the fixing member, to function as a driving member which conveys the recording medium in a normal mode and causes the other member of the pressure member and the fixing member to perform an assist operation for reducing torque of the driving member compared to the normal mode to increase gloss of the image in a high-gloss mode.

Abstract: A heating apparatus includes a cylindrical film, a pressing roller capable of pressing and rotating the cylindrical film to convey a medium through a nip formed between the cylindrical film and the pressing roller, a plurality of heating elements arranged inside the cylindrical film along a longitudinal direction thereof, wherein the heating elements are arranged closer to an upstream end of the nip than a downstream end of the nip, and a guide member arranged inside the cylindrical film and including a first end portion. The first end portion contacts the cylindrical film on a downstream side with respect to the upstream end of the nip.

Abstract: An image heating apparatus includes an endless belt in contact with a toner image on a recording material, a separation member that separates the recording material from the endless belt, a regulation member that regulates a longitudinal position of the endless belt, and an interlocking mechanism. The interlocking mechanism interlocks a movement of an end portion of the separation member on the same side as a first edge of the endless belt with movement of the regulation member. The interlocking mechanism performs interlocking so that, when the regulation member moves toward an upstream in a conveyance direction, the end portion of the separation member moves toward the upstream in the conveyance direction.

Abstract: A fixing device includes a heating unit, a pressure unit, a moving unit, and a controller. The heating unit is configured to heat a toner on a recording medium. The pressure unit is configured to transport the recording medium while sandwiching the recording medium in a nip that the pressure unit and the heating unit form. The moving unit is configured to change a nip state of the pressure unit with respect to the heating unit by moving the heating unit or the pressure unit. The controller is configured to, when plural recording media are transported continuously, control the moving unit so that the moving unit moves the heating unit or the pressure unit in a separation direction so as to reduce a nip width at a recording medium interval between the recording media.

Abstract: A fixing device includes: a fixing element; a heat source heating the fixing element; a press roller pressed against the fixing element, to form with the fixing element a nip region where a recording sheet passes; a driver device rotating the press roller; and a controller controlling the heat source to set a temperature of the fixing element to a predetermined target temperature, and controlling the driver device to set a rotation speed of the press roller to a predetermined target rotation speed. The controller determines the target rotation speed by adding a correction value to a normal rotation speed, based on the temperature of the fixing element at start of job, a type of the recording sheet, ambient temperature, and elapsed time from start of paper feed, and sets the rotation speed of the press roller to the target rotation speed.

Abstract: Provided is an image forming apparatus capable of preventing or suppressing occurrence of density unevenness even when a shearing force is applied between an image face on paper and a fixing belt. The image forming apparatus includes an image former, a fixer, and a controller. The image former forms a toner image constituted by a plurality of dots each containing a toner on paper. The fixer includes a fixing member moving at a first velocity and a pressure member forming a fixing nip portion with the fixing member and moving at a second velocity, and fixes the toner image on the paper at the fixing nip portion. When the first velocity and the second velocity at the fixing nip portion are different, the controller determines a toner amount to be attached to paper so as to make a toner amount distribution different in each of the dots before fixing.

Abstract: An image forming apparatus, including: a determining portion to acquire a density value for respective colors of toners, obtain a sum value of the density values of the colors of the toners, obtain a numerical value indicating the number of the density values being values larger than 0 out of the density values corresponding to the colors of the toners, and determine a target temperature on the basis of the sum value and the numerical value, wherein in a case the sum value is a first value and the numerical value is a first number, the determining portion determines a first temperature as the target temperature, in a case the sum value is the first value and the numerical value is a second number that is larger than the first number, the determining portion determines a second temperature that is lower than the first temperature as the target temperature.

Abstract: A fixing device includes: a fixing member that heats a toner image formed on a recording sheet in order to fix the toner image on the recording sheet; a pressurizing member that nips the recording sheet together with the fixing member to pressurize the toner image on the recording sheet; a heater that heats the pressurizing member; and a hardware processor that controls a heating temperature of the pressurizing member by the heater, wherein the hardware processor acquires setting of glossiness of the toner image and controls the heating temperature to be higher as the glossiness in the setting is lower.

Abstract: Provided is an image forming apparatus capable of preventing or suppressing occurrence of density unevenness even when a shearing force is applied between an image face on paper and a fixing belt. The image forming apparatus includes an image former, a fixer, and a controller. The image former forms a toner image constituted by a plurality of dots each containing a toner on paper. The fixer includes a fixing member moving at a first velocity and a pressure member forming a fixing nip portion with the fixing member and moving at a second velocity, and fixes the toner image on the paper at the fixing nip portion. When the first velocity and the second velocity at the fixing nip portion are different, the controller determines a toner amount to be attached to paper so as to make a toner amount distribution different in each of the dots before fixing.

Abstract: A heating device includes an belt, a heater contacting the belt and divided into heater blocks, a pressing member pressing a sheet against the belt, a temperature sensor disposed on a number of the heater blocks being at least one-half of a total number of the blocks, and a processor configured to select heater blocks based on a width of the sheet, select first temperature sensors on the selected heater blocks not having a non-paper passing region and control electric power supplied to the heater blocks so that temperatures detected by the first sensors are within a predetermined range, and select second temperature sensors on the selected heater blocks having the non-paper passing region and control electric power supplied to the heater blocks having the non-paper passing region to protect against an excessive temperature rise in the non-paper passing region based on second temperatures detected by the second sensors.

Abstract: An image forming apparatus includes an image forming component that forms an image on a recording medium by using a white color material and a color material other than the white color material, and a controller that controls a color material amount of the white color material to differ depending on a position where an image that uses the white color material is formed in order of formation of images that use respective color materials in the image forming component.

Abstract: A pair of rotary members nips and conveys a recording material and a heating element heats a toner image on the recording material via the pair of rotary members. A separating mechanism separates the pair of rotary members. A heating time recording portion records a cumulative length of a period during which the pair of rotary members in an abutted state is heated as a first heating time and a cumulative length of the period during which the pair of rotary members in a separated state is heated as a second heating time. A determining portion determines a remaining lifetime of the pair of rotary members using the first and second heating times and data indicating a relationship between length of the period during which the pair of rotary members is heated and decrease in lifetime of the pair of rotary members.

Abstract: A fixing device according to an embodiment includes an endless belt, a pressure element, a heating member, an adjustment mechanism, and a controller. The pressure element conveys and presses a sheet to the endless belt. The heating member is on the inner side of the belt and has a heat generating element for heating the belt. The adjustment mechanism moves the heating member or the pressure element to adjust the nip width between the heating member and the pressure element. The controller controls the adjustment mechanism so that A>B?N is satisfied, where A is the nip width during a fixing process in which a colored material is fixed to the sheet, B is the nip width during a heating process conducted before the fixing process, and N is the length of the heat generating element in the sheet conveyance direction.

Abstract: A fuser includes a heater, a presser, a support member that supports the presser to allow the presser to move between a nip position where the presser is in pressured contact with the heater, and a separated position where the presser is separated from the heater, a first spring, a first cam, a first gear, a second gear, a second spring, and a second cam. The second cam has a cam profile that, when the presser moves from the separated position to the nip position, causes the second gear to move in a direction along a second axis against urging force of the second spring to increase the urging force of the second spring.

Abstract: A fixing device includes an endless belt, a heater in contact with an inner surface of the belt and divided into a plurality of heater blocks in a width direction of the belt, a pressing member positioned to face the heater with the belt interposed therebetween and configured to press a conveyed sheet against the belt and the heater, a temperature sensor disposed in each of at least half of the heater blocks, and a processor. The processor selects heater blocks based on width and position of the conveyed sheet to form a heat generation block, controls power supplied to the heater blocks so that a temperature of the heat generation block is within a predetermined temperature range, and selects the temperature sensor disposed in a heater block having a non-paper passing region and control an excessive temperature rise in the non-paper passing region.

Abstract: A fixing device includes an endless belt that rotates in a circumferential direction and that comes into contact with a recording medium, which is transported, at an outer peripheral surface of the endless belt, a heat generating plate that includes at least one heat generating portion and extends in an axial direction of the endless belt in such a manner that a surface of the heat generating plate is in contact with an inner peripheral surface of the endless belt, the heat generating portion being formed in such a manner as to extend in the axial direction and in such a manner as to generate heat, a heat conducting unit that is in contact with a rear surface of a portion of the heat generating plate, the portion being different from a portion of the heat generating plate on which the heat generating portion is formed in a transport direction of the recording medium, and that conducts heat generated by the heat generating portion in the axial direction, an urging unit that urges the heat conducting unit towar

Abstract: A fixing device fixes a toner image onto a recording material by applying heat and pressure to the toner image formed on the recording material at a nip provided in a conveyance path of the recording material, and includes: a heating source; a pressure roller and a pressure pad; and a sandwiching member, wherein the pressure pad includes a first main surface and a second main surface, and the first main surface is formed of a long plate-like member, the sandwiching member includes a long plate-like abutting part, and a width-direction center in an area included in the second main surface and corresponding to a recording material passing region provided in the nip bulges toward the abutting part side more than width-direction both ends of the area included in the second main surface and corresponding to the recording material passing region provided in the nip.

Abstract: An image forming apparatus includes an image holding member, a charging unit that charges the surface of the image holding member, an electrostatic latent image forming unit that forms an electrostatic latent image on the charged surface of the image holding member, a developing unit that develops the electrostatic latent image to form a toner image, a transferring unit that transfers the toner image to a first side of a recording medium, a fixing unit that allows the recording medium having the transferred toner image to pass through a nipping region to fix the toner image, a first charging unit that faces the first side of the recording medium and that charges particles, and a second charging unit that charges a second side of the recording medium to the opposite polarity to the charged particles after the recording medium passes through the nipping region.

Abstract: An image forming system comprises a sheet supply section configured to supply a sheet for printing. The system includes a registration roller configured to guide the sheet supplied from the sheet supply section along a conveyance path. A first image forming section is configured to form a first image on the sheet based on reference image information using a first colorant type that is capable of being fixed to the sheet by heat. A fixing section is configured to heat the sheet on which the first image has been formed. A second image forming section is configured to receive the sheet from the fixing section and form a second image using a second colorant type on the sheet after the sheet has been passed through the fixing section. A controller is configured to control a heating temperature of the fixing section in two or more stages.

Abstract: An image forming apparatus includes a first toner image forming unit for forming first toner image on a transfer belt with a first toner and a second toner image forming unit for forming a second toner image on the transfer belt with a second toner. A secondary transfer unit transfers the first and second toner images from the transfer belt to a sheet traveling in a sheet transport direction. A fixing unit fixes the first and second toner images to the sheet. A control unit controls the first toner image forming unit to form a first pattern, the second toner image forming unit to form a second pattern, and to leaving a margin on a upstream side of the sheet in the sheet transport direction that is greater than or equal to a circumferential distance of a fixing element in the fixing unit.

Abstract: An image forming apparatus includes an image forming section and a controller. The image forming section selectively forms a first toner image to be printed on transfer paper other than plain paper with use of a toner and forms a second toner image to be printed on the plain paper with use of the toner. The controller controls the image forming section and thereby makes a first area density of the toner in the first toner image and a second area density of the toner in the second toner image differ from each other.

Abstract: A fixing device includes a first fixing section, a second fixing section, the first fixing section and the second fixing section forming a fixing nip therebetween, a nip width adjusting section capable of adjusting a nip width of the fixing nip, a rotation speed detecting section that detects a rotation speed of the second fixing section, and a hardware processor that controls the nip width adjusting section to make the nip width equal to a predetermined reference nip width.

Abstract: An image forming apparatus includes a fixing device, a driver, and a relay. A control board controls supply of power to a heater based on an output of a temperature detector. A connector includes a first connection portion to be connected to the fixing device, and a second connection portion to be connected to the control board, and connects the fixing device and the control board to each other. A loopback path is configured such that a direct current (DC) voltage to be applied, via a first terminal of the second connection portion, to a second terminal of the first connection portion is applied to a fourth terminal of the second connection portion via a third terminal of the first connection portion. Further, the DC voltage to be applied to the fourth terminal via the loopback path is applied to the relay as a drive voltage for the relay.

Abstract: A fixing device includes a first rotatable member, a second rotatable member, a heat generating member that heats the first rotatable member, and a temperature detecting member that detects a temperature of the heat generating member. A motor drives one of the first rotatable member and the second rotatable member. In addition, a controller controls the fixing device by causing the motor to rotate in a state in which a predetermined amount of electrical power is supplied to the heat generating member, and then, supply of the electrical power to the heat generating member is stopped. On the basis of a temperature lowering rate of a detected temperature of the temperature detecting member during rotation of said motor, the controller detects, after stopping supply of the electrical power to the heat generating member, a rotational state of the one of the first rotatable member and the second rotatable member.

Abstract: Disclosed is image forming apparatus, including a first roller and a second roller that conveys the recording sheet by sandwiching the recording sheet in a fixing process of an image forming; a pressing actuator that presses the first roller and the second roller against each other; an actuating motor that actuates the first roller; a brake that applies a brake force to the second roller; a rotation speed detector that detects a rotation speed of the second roller; and a hardware processor that judges a degradation of each surface roughness of the first roller and the second roller in accordance with the rotation speed of the second roller, which is detected when the first roller is actuated in a situation in which the first roller and the second roller are pressed against each other and when the brake applies a predetermined brake force to the second roller.

Abstract: According to one embodiment, a fuser includes a heat roller, an endless belt, a first press roller and a second press roller. The heat roller rotates and contacts a toner surface side of a sheet, and heats the sheet. The endless belt contacts a part of an outer peripheral surface of the heat roller. The first press roller contacts a part of an inner peripheral surface of the endless belt, and is provided at an insertion part of the sheet in a nip portion where the heat roller contacts the endless belt. The second press roller contacts a part of the inner peripheral surface of the endless belt, is provided at an exit part of the sheet in the nip portion, and has a lower rotational resistance than the first press roller.