Abstract: A heating device includes a rotator, a heater, a heater holder, and a first high thermal conduction member. The heater includes a base and a plurality of heat generators being arranged on the base and including neighboring heat generators. The heater has a gap area between the neighboring heat generators. The first high thermal conduction member has a higher thermal conductivity than the base and faces the gap area.

Abstract: A fixing device includes a rotator, a pressure member, a conductor, and a heater. The pressing member presses the rotator to form a nip between the rotator and the pressing member. The conductor is grounded and includes a contact portion having a limiting shape to limit a contact area in which the contact portion is in contact with an inner circumferential surface of the rotator. The heater is in contact with the inner circumferential surface of the rotator to heat the rotator.

Abstract: A fixing device includes a rotator, a pressure rotator, a heater, and a conductor. The pressure rotator presses the rotator to form a fixing nip between the rotator and the pressure rotator. The heater is in contact with an inner circumferential surface of the rotator and heats the rotator. The conductor is grounded and has a contact portion in contact with a center region of the inner circumferential surface of the rotator in a longitudinal direction of the rotator.

Abstract: A heating device includes a pair of rotators, a heater, a temperature sensor, a conductor, a conductor support, and a component supporting the conductor. The pair of rotators is in contact with each other to form a nip through which a sheet passes. The heater heats at least one of the pair of rotators. The temperature sensor detects a temperature of the heater. The conductor has flexibility and is coupled to the temperature sensor. The conductor support supports the conductor such that a distance from the conductor to at least one position of the heater outside a predetermined region of the heater in a width direction of the sheet is larger than a distance from the conductor to a position of the heater inside the predetermined region in the width direction. The component has a first side facing the heater and a second side opposite the first side.

Abstract: A pressure switching mechanism includes a rotatable support, a biasing member, and a switching rotation member. The rotatable support rotates around a first rotation shaft to support a contact member such that the contact member is movable in a direction toward or away from a contacted member. The biasing member has one end connected to a biased portion of the rotatable support, which is located on a side opposite the first rotation shaft with respect to a virtual line passing through a contact portion between the contact member and the contacted member, and applies a biasing force to the rotatable support. The switching rotation member is connected to another end of the biasing member opposite the one end of the biasing member, rotates around a second rotation shaft, and has a rotation operating end which is on a side opposite the second rotation shaft with respect to the virtual line.

Abstract: A fixing device includes a rotator, a pressure member, a conductor, and a heater. The pressing member presses the rotator to form a nip between the rotator and the pressing member. The conductor is grounded and includes a contact portion having a limiting shape to limit a contact area in which the contact portion is in contact with an inner circumferential surface of the rotator. The heater is in contact with the inner circumferential surface of the rotator to heat the rotator.

Abstract: A heating device includes a heating rotator, a pressure rotator, a planar heater, and a holder. The pressure rotator is configured to press against the fixing rotator to form a nip through which the recording medium is conveyed. The planar heater includes a plurality of heat generators arranged side by side and at least one separation region between the plurality of heat generators. The holder holds the planar heater and contacts the planar heater in a pressure direction in which the pressure rotator presses the heating rotator. The holder includes at least one clearance structure configured to cause a contact area between the planar heater and a portion of the holder corresponding to the at least one separation region to be smaller than a contact area between the planar heater and a portion of the holder not corresponding to the at least one separation region.

Abstract: A heating device includes a rotator, a conductor, a heater, a first facing member, and a second facing member. The conductor is in contact with an inner surface of the rotator. The first facing member has a first facing surface facing a first surface of the conductor. The second facing member has a second facing surface facing a second surface opposite the first surface of the conductor. The first facing member and the second facing member regulate inclination of the conductor.

Abstract: A heating device includes a rotator, a heater, a heater holder, and a first high thermal conduction member. The heater includes a base and a plurality of heat generators being arranged on the base and including neighboring heat generators. The heater has a gap area between the neighboring heat generators. The first high thermal conduction member has a higher thermal conductivity than the base and faces the gap area.

Abstract: A heating device includes a heating rotator, a pressing rotator, and a housing. The heating rotator extends in a longitudinal direction and is configured to heat a sheet. The pressing rotator extends in a longitudinal direction and is configured to press against the heating rotator to form a nip with the heating rotator. The housing houses the heating rotator and the pressing rotator. The housing includes a pair of openings and shutters. The pair of openings face both end portions of the heating rotator in the longitudinal direction of the heating rotator. The shutters are configured to rotate about an axis extending in the longitudinal direction of the heating rotator to open and close the pair of openings.

Abstract: A heating device includes a heating rotator, a pressure rotator, a planar heater, and a holder. The pressure rotator is configured to press against the fixing rotator to form a nip through which the recording medium is conveyed. The planar heater includes a plurality of heat generators arranged side by side and at least one separation region between the plurality of heat generators. The holder holds the planar heater and contacts the planar heater in a pressure direction in which the pressure rotator presses the heating rotator. The holder includes at least one clearance structure configured to cause a contact area between the planar heater and a portion of the holder corresponding to the at least one separation region to be smaller than a contact area between the planar heater and a portion of the holder not corresponding to the at least one separation region.

Abstract: A heating device includes a heating rotator, a pressing rotator, and a housing. The heating rotator extends in a longitudinal direction and is configured to heat a sheet. The pressing rotator extends in a longitudinal direction and is configured to press against the heating rotator to form a nip with the heating rotator. The housing houses the heating rotator and the pressing rotator. The housing includes a pair of openings and shutters. The pair of openings face both end portions of the heating rotator in the longitudinal direction of the heating rotator. The shutters are configured to rotate about an axis extending in the longitudinal direction of the heating rotator to open and close the pair of openings.

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 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 device includes a fixing rotator including a primary portion and a secondary portion disposed outboard from the primary portion in an axial direction of the fixing rotator. A pressure rotator contacts the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium is conveyed. A primary heater heats the primary portion of the fixing rotator. A secondary heater heats the secondary portion of the fixing rotator. A primary temperature detector is isolated from the fixing rotator and detects a temperature of the primary portion of the fixing rotator. A secondary temperature detector contacts the fixing rotator and detects a temperature of the secondary portion of the fixing rotator. The primary temperature detector has a thermal time constant that is smaller than a thermal time constant of the secondary temperature detector.

Abstract: A fixing device is removably installed inside an apparatus body including an apparatus guide. The fixing device includes a convex guide guided along the apparatus guide and a heater to heat a recording medium to fix a toner image on the recording medium. The heater includes a lateral end in a longitudinal direction of the heater. The lateral end is disposed inside the convex guide.

Abstract: A fixing device includes a fixing rotator including a primary portion and a secondary portion disposed outboard from the primary portion in an axial direction of the fixing rotator. A pressure rotator contacts the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium is conveyed. A primary heater heats the primary portion of the fixing rotator. A secondary heater heats the secondary portion of the fixing rotator. A primary temperature detector is isolated from the fixing rotator and detects a temperature of the primary portion of the fixing rotator. A secondary temperature detector contacts the fixing rotator and detects a temperature of the secondary portion of the fixing rotator. The primary temperature detector has a thermal time constant that is smaller than a thermal time constant of the secondary temperature detector.

Abstract: A fixing device is removably installed inside an apparatus body including an apparatus guide. The fixing device includes a convex guide guided along the apparatus guide and a heater to heat a recording medium to fix a toner image on the recording medium. The heater includes a lateral end in a longitudinal direction of the heater. The lateral end is disposed inside the convex guide.

Abstract: A fixing device includes a heat conductor disposed opposite an inner circumferential surface of an endless belt to heat the endless belt. A nip formation pad is disposed opposite the inner circumferential surface of the endless belt and presses the endless belt against a pressing rotary body to form a fixing nip between the endless belt and the pressing rotary body through which a recording medium bearing a toner image is conveyed. A support is disposed opposite an inner circumferential surface of the heat conductor and contacts an abutment face of the nip formation pad to support the nip formation pad against pressure from the pressing rotary body. A heat insulator is interposed between the heater and the nip formation pad and the support to shield the nip formation pad and the support from the heater.

Abstract: An image forming apparatus includes multiple image forming units each accommodating an image bearer and a developer bearer to develop a latent image formed on the image bearer. Each of the image forming units other than a prescribed image forming unit runs in an ordinary reverse rotation mode, in which at least one of the image bearer and the developer bearer rotates in an opposite direction during a non-image formation time period. The prescribed image forming unit runs in a special reverse rotation mode, in which at least one of the image bearer and the developer bearer rotates in the opposite direction during the non-image formation time period based on a differentiated one of a rotation time period, a start timing, a rotational speed, and a frequency of operation from those of the other image forming units, or does not run in the special reverse rotation mode.