Abstract: A fixing device includes a first rotatable member with a heater, a second rotatable member contacting the first rotatable member and forming a fixing nip, a pressing unit pressing the first rotatable member to the second rotatable member in a pressing direction, a pair of side boards disposed with a space in the widthwise direction, and first, second and third stays supporting the pair of side boards. The first stay is provided upstream of a center of the fixing nip in the pressing direction and upstream of the center in a feeding direction of a recording material. The second stay is provided upstream of the center in the pressing direction and downstream of the center in the feeding direction. The third stay is provided downstream of the center in the pressing direction and at least one of upstream and downstream of the center in the feeding direction.

Abstract: An image forming apparatus includes a fixing device and circuitry. The fixing device includes a fixing rotator, an electromagnetic induction heater configured to heat the fixing rotator, and a magnetic flux control member. The circuitry is configured to control the electromagnetic induction heater to lead a temperature of the fixing rotator to a target temperature and change an upper limit of power supplied to the electromagnetic induction heater based on the target temperature.

Abstract: An induction heating and wireless power transferring device that includes: a first working coil and a second working coil that are coupled in parallel; a rectification unit configured to rectify alternating current (AC) power to direct current (DC) power; a first inverter unit configured to convert the DC power into resonant current, and apply the converted resonant current to the first working coil or the second working coil; a first switch coupled to the first working coil and configured to turn on or off the first working coil; a second switch coupled to the second working coil and configured to turn on or off the second working coil; and a control unit configured to control the first inverter unit, the first switch, or the second switch to detect whether a target object is located on the first working coil or the second working coil.

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 laundry treating apparatus include: a cabinet; a tub disposed in the cabinet; a drum rotatably disposed in the tub, and having a cylindrical portion formed of a ferromagnetic material and a rear wall portion for closing an open rear end of the cylindrical portion, wherein the cylindrical portion has a plurality of through-holes formed therein and allows laundry to be loaded thereinto through an opening portion formed on a front surface; an induction heater disposed in the tub and configured to heat the drum by inducing an eddy current in the cylindrical portion; a duct disposed on an outer side of the tub, having an inlet communicating with an open front surface of the cylindrical portion, and an outlet communicating with the tub through a side surface of the tub surrounding the cylindrical portion; and an air blower configured to suction air, discharged from the drum, into the inlet.

Abstract: An energy storage system includes a heat generation apparatus configured to generate heat from electric power and a heat storage device configured to store the heat generated by the heat generation apparatus, the heat generation apparatus including an electric motor connected to an electric power system and rotated by surplus electric power received from the electric power system, and a heat generator having a rotary unit rotated by the electric motor and a heat generating unit configured to generate heat through electromagnetic induction, and configured to convert rotational force of the electric motor to heat.

Abstract: A printer 1 including an image forming portion using toner containing a wax, a transfer portion for transferring an image onto a sheet, a belt unit and a pressing roller which heat the sheet in a nip, a duct including an air suction port for sucking air from a sheet inlet, a filter provided on the duct and for collecting dust, and a fan provided on the duct and for sucking the air includes a detector for detecting a temperature in the neighborhood of the belt unit and a control circuit portion for effecting control so that an air flow rate of the fan is weakened in the case where the temperature in the neighborhood of the belt unit is high during an image forming process and so that the air flow rate of the fan is weakened in the case where the temperature is high.

Abstract: The present invention provides a structure of resistor element, which comprises a protective layer around electrodes to elongate the path of corrosion when gaseous water or sulfur leaking in. Therefore, the protective layer structure can elongate the life of the resistor element.

Abstract: A laundry apparatus is provided. The laundry apparatus may include a cabinet, a tub provided in the cabinet and defining an internal space, the tub having an opening formed in a front of the tub, a drum rotatably provided in the internal space of the tub and being made of a conductor, and an induction heater provided at an outer circumferential surface of the tub. The induction heater may heat the drum by generating an electromagnetic field and may include a coil that uses a supplied electric current to generate an eddy current in the drum by generating a magnetic field, and a coil arranging portion provided at the outer circumferential surface of the tub. The coil may be arranged on the coil arranging portion such that coils of the coil are spaced a predetermined distance apart from each other while being wound from a front direction to a rear direction of the tub.

Abstract: A coil module includes: a coil formed by winding a coil wire; and an insulating member. The coil includes a first wound portion and a second wound portion, the first wound portion being formed to surround the winding axis, the second wound portion being formed at a position adjacent to the first wound portion on an outer perimeter side of the coil. The insulating member includes a first insulating portion configured to cover a perimeter surface of the first wound portion, and a second insulating portion configured to cover a perimeter surface of the second wound portion. A portion of a surface of the first insulating portion located on the outer perimeter side of the coil is in contact with a portion of a surface of the second insulating portion located on the winding axis side.

Abstract: The distance measuring apparatus according to the present invention may comprise: a distance measuring unit; a motor; and a rotary wireless transceiver, comprising a rotor core rotated by the motor, a stator core, and power coils and signal coils respectively wound around the rotor core and the stator core, configured to wirelessly supply power to the power coil wound around the rotor core via the power coil wound around the stator core and wirelessly transmit the signal output from the distance measuring unit to the signal coil wound around the stator core via the signal coil wound around the rotor coil. The rotor core and the stator core may be in a shape of a circular plain such that the rotor core and the stator core face each other with a plane, perpendicular to a rotation axis of the motor, interposed between them.

Abstract: The present invention uniformly cools a roll body and/or an induction heating mechanism by gas without complicating the configuration around the roll body. An induction heated roll apparatus includes a roll body having a hollow part, an induction heating mechanism disposed in the hollow part to subject the roll body to induction heating, and a cooling mechanism to cool the roll body and/or the induction heating mechanism by generating a gas flow in a clearance between the roll body and the induction heating mechanism. The cooling mechanism includes a suction port disposed on one axial end side of the roll body that communicates with the clearance, an exhaust port disposed on an opposite axial end side of the roll body that communicates with the clearance, and a suction mechanism coupled to the exhaust port that sucks the gas in the clearance from the exhaust port.

Abstract: A motor system includes a stator, a rotor, a number of power modules which each have planar contact faces for dissipating heat, a control device which is designed to actuate the power modules, a housing, wherein the stator and the rotor are arranged inside the housing, and at least one heat sink. The heat sink has a number of planar contact faces which are connected in a thermally conductive fashion to respectively corresponding contact faces of the power modules. The heat sink has regions for dissipating heat, wherein a coolant flows around the regions in order to dissipate heat.

Abstract: A heating device includes a heater that includes a heat generator configured to generate heat as the heat generator is supplied with power. A feeding member is configured to contact the heater and feed the power to the heat generator. The feeding member is made of a corson copper alloy.

Abstract: An apparatus includes an image former and an induction heating fusing device. The image former forms an image. The induction heating fusing device fuses the image formed by the image former onto paper. Whether the induction heating fusing device has an error is determined by limiting a current applied to a resonance circuit included in the induction heating fusing device to less than a certain level.

Abstract: An induction heating system includes interchangeable secondary induction heating assemblies and/or secondary induction heating coil flux concentrators that are specifically configured for the particular type of weld being created and/or the particular weld joint where the weld is created. For example, the secondary induction heating assemblies and/or secondary induction heating coil flux concentrators may have specific physical configurations (e.g., shapes, contours, etc.) and/or include specific materials (e.g., ferrites) that are well suited for the particular type of weld being created and/or the particular weld joint where the weld is created.

Abstract: A dryer appliance is provided including a cabinet and a drum defining a chamber and being rotatably mounted within the cabinet. An inlet duct is fluidly coupled to a chamber inlet and an air handler urges a flow of air through the inlet duct and into the chamber. An induction heating assembly is in thermal communication with the inlet duct and includes an induction coil for generating an electromagnetic field and a heating plate for generating heat when energized by the electromagnetic field. The induction heating assembly may be positioned proximate a rear wall of the chamber or in a heater box below the chamber. In addition, the heating plate may form part of a rear wall of the drum or may be positioned behind the rear wall.

Abstract: The present disclosure relates to an image forming apparatus that forms toner images on a recording material. A control unit is configured to set, when performing fixing processing to fix a toner image onto the recording material, a first mode where thermal generation distribution of the heater is switched in accordance with electric power supply to the heater, a second mode where thermal generation distribution of the heater is switched in accordance with the electric power supply to the heater and temperature at the non-sheet-passing portion, and a third mode where the blower unit is driven in accordance with temperature at the non-sheet-passing portion.

Abstract: The effect of decreasing the inductance, which cancels the recovery current generated upon the switching operation of the switching element, is enhanced. Provided are a circuit body which has first and second switching elements constituting upper and lower arm circuits and a conductor portions, a metal member, and a relay conductor portion which is arranged to face the metal member with the circuit body interposed therebetween and electrically connected to a terminal connected to any one of conductor portions. An eddy current is induced at the metal member and the relay conductor portion by the recovery current flowing through the conductor portions according to the switching operation of the first and second switching elements.

Abstract: The present invention intends to reduce unbalance among phase currents without use of a Scott connection transformer. The present invention is an induction heating system adapted to use a three-phase AC power source to operate a first induction heating apparatus including a first induction coil and a second induction heating apparatus including a second induction coil. In addition, the number of turns of the second induction coil is an even number. Also, one of a winding start point and a winding end point of the first induction coil is electrically connected to one phase of the three-phase AC power source, and the other one is electrically connected to a midpoint of the second induction coil. Further, the winding start point and the winding end point of the second induction coil are electrically connected to the remaining two phases of the three-phase AC power source.

Abstract: The present disclosure relates to a wastewater flue evaporating device. An wastewater evaporation crystallizer is provided, including an evaporating tube inlet, an inlet flange, an inlet chamber, a pneumatic inlet baffle, an evaporating tube body, a pneumatic outlet baffle, an outlet chamber, an outlet flange, and an evaporating tube outlet which are successively coupled, where the evaporating tube inlet is connected to provide a gas pipeline; the gas pipeline is connected on a flue between an external denitration device and an air preheater; the evaporating tube outlet is communicated with an inlet flue of a dust collector; the evaporating tube body is provided with a wastewater nozzle; and the wastewater nozzle is communicated with a pretreated waste pipe. The present disclosure provides an efficient and energy-saving wastewater evaporation crystallizer which increases evaporation efficiency by bringing in a high-temperature gas at a front end of the air preheater.

Abstract: The present invention intends to eliminate the need for a temperature detecting element adapted to measure the temperature of a roll main body in an induction-heated roller apparatus, and includes an impedance calculation part that calculates the impedance of a winding, a relational data storage part that stores relational data indicating the relationship between the impedance of the winding and the temperature of the roll main body, and a roll temperature calculation part that calculates the temperature of the roll main body from the impedance obtained by the impedance calculation part and the relational data stored in the relational data storage part.

Abstract: A fixing apparatus includes a belt including a ferromagnetic layer. A ferromagnetic plate is disposed inside the belt and has a Curie point that is lower than a Curie point of the ferromagnetic layer. An induction heater causes heat generation in the ferromagnetic layer and the ferromagnetic plate. The induction heater includes a coil. A driving circuit outputs a high frequency current to the coil, and changes the high frequency current. A temperature sensor measures a temperature of the coil. A controller controls the driving circuit to decrease the high frequency current if the temperature of the coil measured by the temperature sensor is higher than a predetermined value.

Abstract: An image heating apparatus for heating an image formed on a recording material includes a tubular rotary member including a conductive layer, a magnetic core inserted into a hollow portion of the rotary member, a coil helically wound around an outer side of the magnetic core in the hollow portion, and a control unit configured to control a frequency of an alternating current flowing through the coil, in which the conductive layer generates heat by an electromagnetic induction in an alternating magnetic field formed when the alternating current flows through the coil, and the control unit controls the frequency in accordance with a size of the recording material.

Abstract: The present invention intends to run one induction heating apparatus using a three-phase AC power supply without use of a Scott connection transformer while preventing an occurrence of a phase where no current flows. An induction heating system uses the three-phase AC power supply to run the induction heating apparatus including an induction heating coil, and has an intermediate apparatus including a coil that is wound on an iron core with an even number of turns, forming a closed magnetic circuit. Additionally, a winding start point of the induction heating coil is connected to the U phase of the three-phase AC power supply and a winding end point of the same is connected to a midpoint of the intermediate coil. The winding start point and end point of the intermediate coil are connected to the V and W phases of the three-phase AC power supply, respectively.

Abstract: Disclosed is a cylindrical rotary member including a conductive layer; a coil disposed inside the rotary member, the coil including a helical portion having a helical axis that is substantially parallel to a generatrix direction of the rotary member, the coil forming an alternating magnetic field to generate heat in the conductive layer by electromagnetic induction; a core disposed inside the helical portion, the core inducing a line of magnetic force of the alternating magnetic field; a roller coming in contact with an outer surface of the rotary member to form a fixing nip portion; and a metal stay disposed inside the rotary member, in which an image on a recording material is fixed to the recording material by being heated at the fixing nip portion and the stay is disposed outside the coil and has a shape that does not form an electrical loop around the coil.

Abstract: A fixing device includes a roller, an endless belt, and a heat generating member disposed in a space inside the endless belt, extending in a width direction of the endless belt, and pressing the endless belt against the roller. A sheet is passed through a nip formed between the roller and a portion of the endless belt pressed by the heat generating member, such that an image on the sheet is fixed thereto. The heat generating member includes first and second heat generating portions that are adjacent to each other along the width direction, and the first portion heat generating is independently operable from the second heat generating portion.

Abstract: A fixing device includes a roller, an endless belt, and a heat generating member disposed in a space inside the endless belt, extending in a width direction of the endless belt, and pressing the endless belt against the roller. A sheet is passed through a nip formed between the roller and a portion of the endless belt pressed by the heat generating member, such that an image on the sheet is fixed thereto. The heat generating member includes first and second heat generating portions that are adjacent to each other along the width direction and independently operable from each other. A boundary of the first and second heat generating portions extends in a direction inclined with respect to a sheet conveying direction.

Abstract: An image forming apparatus has a fixing device for heating and fixing an unfixed image formed on a recording material. The fixing device includes a heater having a heat generating element and a substrate, a heat leveling member contacting the heater and having a thermal conductivity higher than that of the substrate, and a temperature detector for detecting the temperature of the heat leveling member. The apparatus also has a controller for controlling electric power supplied to the heat heater to maintain a target temperature. The period in which the heat controller raises the target temperature with an increase of a number of the recording materials is provided in a period in which recording materials having widths smaller a width of a maximum size recording material usable with the device are continuously subjected to fixing operations.

Abstract: A fixing device configured to fix an image on a recording material, includes: a rotary member including an electroconductive layer; a coil which has a spiral shaped portion and is disposed in the inside of the rotary member; and a core disposed in the spiral shaped portion; with magnetic resistance of the core being, with an area from one end to the other end of the maximum passage region of the image on the recording material regarding the generatrix direction, equal to or smaller than 30% of combined magnetic resistance made up of magnetic resistance of the electroconductive layer and magnetic resistance of a region between the electroconductive layer and the core.

Abstract: An image heating apparatus for heating an image includes a cylindrical rotatable member including an electroconductive layer; a helical coil provided in the rotatable member, the coil having a helix axis extending along a generatrix direction of the rotatable member; a magnetic core provided in the coil and having an end portion; and a controller configured to control a frequency of an AC current supplied to the coil; wherein the image is heated by heat of the rotatable member heated by electromagnetic induction heat generation of the electroconductive layer, wherein the controller sets the frequency to a first frequency corresponding to a size of a recording material, and wherein the controller sets the frequency to a second frequency higher than the first frequency when a print ratio of the image is larger than a predetermined value.

Abstract: An electrophotographic member includes a rubber layer having a lightness of 15 or less and including a marked portion formed so as to have a depth of 35 ?m or more and 100 ?m or less, a fluorine-based resin layer having a light transmittance of 60% or more, and an adhesive layer disposed between the rubber layer and the fluorine-based resin layer. The adhesive layer has a lightness of 60 or more and has a thickness of 3 ?m or more and 10 ?m or less in a portion surrounding the marked portion.

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 apparatus includes a fixing belt to fix an unfixed image on a sheet, an induction current generator configured to generate in the fixing belt an induction current that causes heating thereof, a shutdown unit disposed near a surface of the fixing belt and configured to cause shutdown of the fixing apparatus when a temperature of the shutdown unit reaches a first predetermined temperature, a temperature detecting unit disposed near the surface of the fixing belt and configured to detect a temperature at a location of the temperature detecting unit, and a control unit configured to turn off the induction current generator when the detected temperature reaches a second predetermined temperature that is smaller than the first predetermined temperature.

Abstract: A fixing device includes: first and second rotatable members configured to heat-fix, at a nip therebetween, a toner image formed on a sheet by using a toner containing a parting agent; a heating portion, provided opposed to an outer surface of the first rotatable member, configured to heat the first rotatable member through electromagnetic induction heating; a holding portion configured to hold the heating portion; and an extended portion configured to extend from the holding portion so as to close a gap between itself and the first rotatable 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 fuser for thermally fixing a toner image on a recording medium includes: an endless fusing belt configured to transfer heat to the toner image; a heat source configured to heat the fusing belt; a detection unit configured to detect peripheral inward deformation of the fusing belt; and a power cut-off unit configured to cut off power supplied to the heat source upon detection of the peripheral inward deformation of the fusing belt by the detection unit.

Abstract: A fixing device configured to fix an image on a recording material, includes: a rotary member including an electroconductive layer; a coil which has a spiral shaped portion and is disposed in the inside of the rotary member; and a core disposed in the spiral shaped portion; with magnetic resistance of the core being, with an area from one end to the other end of the maximum passage region of the image on the recording material regarding the generatrix direction, equal to or smaller than 30% of combined magnetic resistance made up of magnetic resistance of the electroconductive layer and magnetic resistance of a region between the electroconductive layer and the core.

Abstract: An image forming apparatus includes an image forming unit that forms an image on a recording medium by using a developer and an energy generating unit that generates energy that causes the developer on the recording medium, on which the image has been formed by the image forming unit, to generate heat.

Abstract: An image forming apparatus includes a fixing member, a heat source, a nip forming member, a pressing member, a recording medium conveyor, a first temperature detector to detect a temperature of a non-sheet-passing area of the fixing member through which a recording medium does not pass, a second temperature detector to detect a temperature of the recording medium, and a controller to adjust a time to drive the recording medium conveyer to control a time interval between successive recording media and a changing time to change the time interval, according to a temperature detected by the second temperature detector in response to a temperature rise in the non-sheet-passing area of the fixing member detected by the first temperature detector.

Abstract: A fixing device configured to fix an image on a recording material, includes: a rotary member including an electroconductive layer; a coil which has a spiral shaped portion and is disposed in the inside of the rotary member; and a core disposed in the spiral shaped portion; with magnetic resistance of the core being, with an area from one end to the other end of the maximum passage region of the image on the recording material regarding the generatrix direction, equal to or smaller than 30% of combined magnetic resistance made up of magnetic resistance of the electroconductive layer and magnetic resistance of a region between the electroconductive layer and the core.

Abstract: A fixing device includes a fixing rotator and an opposed rotator disposed opposite the fixing rotator to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater disposed opposite the fixing rotator heats the fixing rotator. A nip formation pad disposed opposite an inner circumferential surface of the fixing rotator includes a decreased thermal conduction portion having a decreased thermal conductivity to conduct heat in a thickness direction of the nip formation pad perpendicular to an axial direction of the fixing rotator and an increased thermal conduction portion having an increased thermal conductivity to conduct heat in the thickness direction of the nip formation pad. The increased thermal conduction portion is disposed opposite an overheating span of the fixing rotator in the axial direction thereof where the fixing rotator is susceptible to overheating.

Abstract: A fixing device includes: a sensor circuit portion which includes a plurality of series circuits of thermistors and capacitors and in which the capacitors differ from each other in capacitance; a signal circuit portion to which each sensor output voltage that is a voltage between the thermistor and the capacitor is input and which switches between output levels each time the sensor output voltage that exceeds a threshold value is increased; and a processing circuit that includes a output port to which the series circuits are connected so as to be parallel to each other and an input port and that recognizes a target temperature to be detected with each of the thermistors based on a rising time since the start of the voltage application to each of the series circuits until the output signal rises and a falling time until the output signal falls that are measured.

Abstract: When the control unit makes both the first and second inverter circuits operational, the control unit controls the first and second inverter circuits by duty control such that an average heating output from the first inverter circuit reaches a predetermined first target heating output, and an average heating output from the second inverter circuit reaches a predetermined second target heating output. When the control unit makes one of the first and second inverter circuits operational in an automatic heating mode for automatic heating control according to a predetermined heating output sequence, the control unit inhibits the first and second inverter circuits from being controlled by the duty control.

Abstract: An induction heating fusing device and method of an image forming apparatus including: a pressure roller; a heating element that forms a fusing nip together with the pressure roller and is rotatable; an inductor that is installed in a rotation axis direction on the outer circumference surface of the heating element, includes a main coil and a plurality of control coils located on the main coil, and inductively heats the heating element; and a controller that selectively drives at least one of the plurality of control coils depending on the width of a printing paper passing though the fusing nip, and controls the main coil and the plurality of control coils so that a current direction of the main coil and a current direction of the plurality of control coils become the same as or opposite to each other depending on the width of the printing paper.

Abstract: To appropriately adjust a fixing temperature according to the amount of applied toner, an image forming apparatus for controlling a temperature of a fixing unit configured to fix a color material on a printing sheet, acquires a color material amount of each page of image data of a plurality of pages, determines whether a setting for printing image data of the plurality of pages on a printing sheet has been performed, determines one color material amount out of a plurality of acquired color material amounts if it is determined that the setting for printing image data of the plurality of pages on one printing sheet has been performed, and controls the temperature of the fixing unit using a fixing temperature corresponding to the determined color material amount.

Abstract: A fixing device includes a rotator having a heat generation layer, an excitation coil to inductively heat the heat generation layer, ferromagnetic cores to direct magnetic flux arising from the excitation coil to the rotator, and a holder to hold the excitation coil and the ferromagnetic cores. In the fixing device, the ferromagnetic cores include multiple cores disposed astride the excitation coil at a turning part on each end of the excitation coil in a longitudinal direction of the excitation coil.

Abstract: A semiconductor substrate thermal treatment apparatus enables excellent heating control in suppressing influence of mutual induction between induction heating coils even when the induction heating coils are arranged in the vertical direction while providing horizontal magnetic flux to susceptors. The apparatus indirectly heats wafers mounted on horizontally-arranged susceptors including induction heating coils to form alternate-current magnetic flux in a direction parallel to a mount face of the susceptor. The wafer are arranged at an outer circumferential side of the susceptor. The induction heating coils are structured with at least one main heating coil and subordinate heating coils electromagnetically coupled with the main heating coil.

Abstract: In a fixing device thermally fixing toner images on recording sheets of various sizes, (i) a conductive heat generating rotational body configured to heat toner images, (ii) an excitation coil positioned along a part of an outer circumferential surface of the heat generating rotational body and configured to generate a magnetic flux to heat the heat generating rotational body by electromagnetic induction, and (iii) a demagnetization coil positioned close to the excitation coil so as to cover a part of the excitation coil and configured to cancel, when a toner image is being fixed on a smaller-sized recording sheet, a part of the magnetic flux generated by the excitation coil so that overheating is prevented in a non sheet-passing region, are provided. The demagnetization coil has a thickness smaller than a thickness of the excitation coil in an axis direction of the coils.

Abstract: A temperature detection unit is arranged in a position between a magnetic field generation coil and a magnetic core that lies inside a heat generation member. A cut portion for exposing the temperature detection unit through the magnetic core has a thickness when seen in a cross section in the direction of a magnetic flux.