Abstract: According to an embodiments, a fixing device includes: an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.

Abstract: A nip formation assembly disposed opposite an opposed rotator via an endless belt includes a nip formation pad to press against the opposed rotator via the endless belt to form a fixing nip between the endless belt and the opposed rotator, through which a recording medium bearing a toner image is conveyed. A fixing heater is disposed opposite at least a center span of the endless belt in an axial direction thereof where the recording medium is conveyed. The fixing heater heats the endless belt. A lateral end heater is mounted on the nip formation pad and disposed opposite a lateral end span of an inner circumferential surface of the endless belt in the axial direction thereof. The lateral end heater heats the endless belt.

Abstract: A fixing device includes a flexible, tubular fixing rotator rotatable in a predetermined direction of rotation and an opposed rotator disposed opposite the fixing rotator. A nip formation pad presses against the opposed rotator via the fixing rotator to form a fixing nip between the fixing rotator and the opposed rotator, through which a recording medium bearing a toner image is conveyed. A fixing heater is disposed opposite at least a conveyance span of the fixing rotator in an axial direction thereof where the recording medium is conveyed to heat the fixing rotator. A lateral end heater is mounted on the nip formation pad and disposed opposite an inner circumferential surface of the fixing rotator at a lateral end of the fixing rotator in the axial direction thereof to heat the fixing rotator. A supplementary thermal conductor contacts the fixing rotator and the lateral end heater.

Abstract: A fixing device includes a heater to generate heat and a fixing rotator to rotate while contacting the heater. A pressure rotator presses against the heater via the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium bearing a toner image is conveyed. The heater includes an insulative substrate and a resistive heat generation layer mounted on the substrate. The resistive heat generation layer is disposed upstream from a center of the fixing nip in a recording medium conveyance direction.

Abstract: A fixing device includes a fixing rotator and an opposed rotator pressed against the fixing rotator to form a fixing nip therebetween. A primary heater is disposed opposite the fixing rotator in a circumferential span of the fixing rotator other than the fixing nip in a circumferential direction of the fixing rotator to heat the fixing rotator. A heat shield is interposed between the primary heater and the fixing rotator and disposed outboard from at least a decreased size recording medium conveyance span of the fixing rotator spanning in an axial direction of the fixing rotator where a recording medium having a decreased size in the axial direction of the fixing rotator is conveyed. The heat shield shields the fixing rotator from the primary heater. A secondary heater is mounted on the heat shield to heat the fixing rotator.

Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and including a heated face and a heater including a contact face contacting the heated face of the fixing rotator. The contact face has a Vickers hardness not greater than about 600 Hv.

Abstract: Heat-equalizing rotation of a fixing member and a pressing member for equalizing the distribution of the temperature of a surface of the fixing member in a width direction is performed after a recording medium having a size less than or equal to a predetermined size in the width direction passes a nip portion and before a recording medium having a size greater than the predetermined size in the width direction passes the nip portion. Further, a termination condition of the heat-equalizing rotation is selected from among a plurality of different kinds of termination conditions, based on image formation related information related to next image formation performed after the heat-equalizing rotation.

Abstract: A fixing device may include an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.

Abstract: A fixing device includes a fixing rotator rotatable in a given direction of rotation and a pressure rotator pressed against the fixing rotator to form a fixing nip therebetween, through which a recording medium is conveyed. A first heater is disposed opposite the fixing rotator with a first interval therebetween to heat the fixing rotator. A reflector reflects light emitted by the first heater to the fixing rotator. The reflector is disposed opposite the first heater with a second interval therebetween that is greater than the first interval.

Abstract: A fixing device includes a fixing rotator and a heater disposed inside the fixing rotator to heat the fixing rotator with radiant heat. A pressure rotator presses against the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator. A reflector is disposed opposite the heater to reflect the radiant heat radiated from the heater to the fixing rotator. The reflector includes a first parallel plane, a second parallel plane, and a third tilt plane. The second parallel plane is parallel to the first parallel plane and stepped with respect to the first parallel plane. The second parallel plane is disposed closer to the fixing nip and the heater than the first parallel plane. The third tilt plane bridges the first parallel plane and the second parallel plane and is disposed opposite the heater.

Abstract: A fixing device to fix a toner image on a sheet includes a first rotary member that rotates in a predetermined direction and a second rotary member that contacts an outer circumferential surface of the first rotary member. A stationary member is fixed inside the first rotary member to press the first and second rotary members together to form a nip portion between the rotary members. A reinforcement member is fixedly provided inside the first rotary member and pressed against the stationary member. The fixing device includes heat source to heat the first rotary member and a reflector to reflect heater light emitted from the heat source toward the first rotary member.

Abstract: A fixing device includes a primary heater disposed opposite a fixing rotator to heat a circumferential span of the fixing rotator other than a fixing nip formed between the fixing rotator and a pressure rotator and a secondary heater disposed outboard from the primary heater in an axial direction of the fixing rotator to heat the fixing rotator at the fixing nip. The primary heater and the secondary heater heat a bi-heating span of the fixing rotator in the axial direction thereof. The secondary heater heats a mono-heating span of the fixing rotator in the axial direction thereof and generates a decreased amount of heat to be conducted to the bi-heating span of the fixing rotator. The decreased amount of heat is smaller than an increased amount of heat to be conducted to the mono-heating span of the fixing rotator that is heated by the secondary heater only.

Abstract: A fixing device includes a primary heater, a secondary heater, and a tertiary heater to heat a primary heating span, a secondary heating span, and a tertiary heating span of a fixing rotator, respectively. A primary temperature detector and a secondary temperature detector detect a temperature of the fixing rotator. A tertiary temperature detector detects a temperature of a pressure rotator. A controller selectively performs a primary control mode to de-energize the tertiary heater and a secondary control mode to connect the secondary heater and the tertiary heater in series to energize the primary heater, the secondary heater, and the tertiary heater. The controller energizes the secondary heater and the tertiary heater in the secondary control mode based on the temperature of the fixing rotator and the pressure rotator detected by the secondary temperature detector and the tertiary temperature detector, respectively.

Abstract: A fixing device includes a nip formation pad to press against a fixing rotator. A primary heater is disposed opposite the fixing rotator in a primary heating span spanning in an axial direction of the fixing rotator to heat the primary heating span of the fixing rotator from which heat is conducted to the nip formation pad with a primary conduction. A secondary heater is disposed opposite the fixing rotator in a secondary heating span that is outboard from the primary heating span in the axial direction of the fixing rotator. The secondary heater is interposed between a first nip formation portion and a second nip formation portion of the nip formation pad to heat the secondary heating span of the fixing rotator through the nip formation pad from which heat is conducted to the fixing rotator with a secondary conduction greater than the primary conduction.

Abstract: A fixing device includes a first heater and a second heater to heat a fixing rotator. The first heater includes a first heat generator having a first heating span in a longitudinal direction of the first heater and a first support supporting the first heat generator. The second heater includes a second heat generator having a second heating span in a longitudinal direction of the second heater and a second support supporting the second heat generator. A screen screens one of the first heater and the second heater from another one of the first heater and the second heater. At least one of the first support and the second support is disposed in proximity to a lateral end of at least one of the first heat generator and the second heat generator in the longitudinal direction of the first heater and the second heater.

Abstract: A fixing device includes a nip formation pad that presses against a pressure rotator via an endless belt to form a fixing nip between the belt and the pressure rotator, through which a recording medium bearing a toner image is conveyed. A fixing heater is disposed opposite at least a center span of a conveyance span of the belt in an axial direction thereof where the recording medium is conveyed to heat the belt. A first lateral end heater and a second lateral end heater are mounted on the nip formation pad and disposed opposite a first lateral end span and a second lateral end span of an inner circumferential surface of the belt in the axial direction thereof, respectively, to heat the belt. The second lateral end heater is electrically connected in series to the first lateral end heater.

Abstract: A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween, through which multiple recording media, each spaced apart from each other by an interval distance in a conveyance direction, are sequentially conveyed at a conveyance speed. The heater is disposed adjacent to the fuser member to heat the fuser member. The controller is operatively connected to the heater to control power supply to the heater through a series of on-off switching control cycles, each including an on-time during which the heater power supply is on, and an off-time during which the heater power supply is off, in synchronization with conveyance of the recording medium.

Abstract: A fixing device includes a fixing rotator and an opposed rotator pressed against the fixing rotator to form a fixing nip therebetween. A primary heater is disposed opposite the fixing rotator in a circumferential span of the fixing rotator other than the fixing nip in a circumferential direction of the fixing rotator to heat the fixing rotator. A heat shield is interposed between the primary heater and the fixing rotator and disposed outboard from at least a decreased size recording medium conveyance span of the fixing rotator spanning in an axial direction of the fixing rotator where a recording medium having a decreased size in the axial direction of the fixing rotator is conveyed. The heat shield shields the fixing rotator from the primary heater. A secondary heater is mounted on the heat shield to heat the fixing rotator.

Abstract: A fixing device includes a fixing rotator formed into a loop and rotatable in a predetermined direction of rotation and a pressure rotator disposed outside the loop formed by the fixing rotator and pressed against the fixing rotator to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A stay is disposed opposite the pressure rotator via the fixing rotator. A heater is disposed opposite an inner circumferential surface of the fixing rotator to heat the fixing rotator. A pressurization member is pressed against the heater via the fixing rotator. A housing is interposed between the stay and the heater. A temperature detector is mounted on the housing to detect a temperature of the heater.

Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, and a stationary member. The heater heats the metal member. The fixing member is disposed rotatable around the metal member. An inner circumferential surface of the fixing member is heated by the metal member to heat and fix a toner image. The rotary pressing member is disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip between the rotary pressing member and the fixing member through which a recording medium bearing the toner image passes. The stationary member is disposed in pressure contact with the inner circumferential surface of the fixing member, and has an opposing face opposing the rotary pressing member and having a curvature smaller than a curvature of the rotary pressing member.