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 first heater and a second heater disposed inside a fixing rotator to heat the fixing rotator. The first heater generates an increased amount of heat and includes a first heat generator having a first heating span in a longitudinal direction of the first heater. The second heater generates a decreased amount of heat and includes a second heat generator having a second heating span in a longitudinal direction of the second heater. A partition is interposed between the first heater and the second heater to define a first compartment having an increased size and accommodating the first heater and a second compartment having a decreased size and accommodating the second heater.

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 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 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 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 rotatable fixing member, a pressing member to contact the fixing member with pressure to form a nip between the pressing member and the fixing member, an induction heating unit serving as a heating source to heat the fixing member, and a conductive wire drawn out of the induction heating unit to be disposed outside the cover member through a hole provided substantially at a center of the cover member in a longitudinal direction of the induction heating unit. The induction heating unit includes an excitation coil, a coil holder to hold the excitation coil, and a cover member provided facing the coil holder with the coil holder interposed between the cover member and the fixing member.

Abstract: A fixing device includes a rotatable fixing member, a pressing member to contact the fixing member with pressure to form a nip between the pressing member and the fixing member, an induction heating unit serving as a heating source to heat the fixing member, and a conductive wire drawn out of the induction heating unit to be disposed outside the cover member through a hole provided substantially at a center of the cover member in a longitudinal direction of the induction heating unit. The induction heating unit includes an excitation coil, a coil holder to hold the excitation coil, and a cover member provided facing the coil holder with the coil holder interposed between the cover member and the fixing member.

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 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 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 first heater and a second heater disposed inside a fixing rotator to heat the fixing rotator. The first heater generates an increased amount of heat and includes a first heat generator having a first heating span in a longitudinal direction of the first heater. The second heater generates a decreased amount of heat and includes a second heat generator having a second heating span in a longitudinal direction of the second heater. A partition is interposed between the first heater and the second heater to define a first compartment having an increased size and accommodating the first heater and a second compartment having a decreased size and accommodating 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 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 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 rotary member comprising a heat generation layer; an excitation coil generating magnetic flux, disposed along an axial direction of the rotary member and opposite the rotary member, to heat by induction the heat generation layer; a first demagnetizing coil layered on the excitation coil and generating magnetic flux in a direction reverse to and cancel the magnetic flux that the excitation coil generates; a sheet size detector to obtain a size of a recording sheet on which an image is to be formed by passing through the rotary member; and a drive controller to control driving of the first demagnetizing coil. The drive controller drives the first demagnetizing coil after information including the sheet size information has been obtained.

Abstract: A fixing device includes a rotary fixing member; a pressure roller pressed against the fixing member to form a nip in association with the fixing member; and an induction heater, as a heat source, to heat the fixing member. The induction heater includes an excitation coil to induction-heat the fixing member; a side core disposed along an outer circumference in a longitudinal direction of the excitation coil; and a plurality of arch-shaped cores disposed to cover the excitation coil in the longitudinal direction thereof. The arch-shaped cores include center portions corresponding to an inner side of the excitation coil and bent to the fixing member; and outer end portions extending in the direction leading to the side core without interfering with the excitation coil.