Abstract: A fixing unit includes: a casing; a heat roller that is rotatably supported and that supplies heat for fixing; and a tubular heater disposed in parallel in the heat roller along an axis thereof. The tubular heater includes a lead wire having a protruding end portion protruding outwardly from an axial end portion thereof. In addition, the tubular heater includes a flat terminal having one face thereof connected and fixed to the protruding end portion. Moreover, a fitting surface for fixing the flat terminal is formed in the casing. The fitting surface is arranged to be flat in an area excluding an area in which the protruding end portion is disposed and is provided with a clearance for storing the protruding end portion. Further, the flat terminal is fixed to the fitting surface with the one face of the flat terminal facing the fitting surface.

Abstract: When a main switch 11 is off, an electricity storage device 93 is charged with electric power of a commercial AC power supply 80 . When the main switch 11 is on and warming-up of a fixing unit 35 is necessary, a halogen heater 51 in a heating roller 41 is actuated by the electric power of the commercial AC power supply 80 and a halogen heater 52 in the heating roller 41 is actuated by discharge electric power of the electricity storage device 93.

Abstract: An image forming system has an image forming device for forming an image on a recording material in accordance with a set width of the recording material, and an image heating member. A first detecting member which detects a temperature of a first region of the image heating member, the first region corresponding to an outside region of a contact area, the contact area being contactable with a recording material having the set width, a second detecting member which detects a temperature of a second region of the image heating member, the second region corresponding to an inside region of the contact area, a cooling portion cools the first region of the image heating member in accordance with an output of the first detecting member, and a notification portion notifies that the set width of the recording material is wrong in accordance with an output of the first detecting member and an output of the second detecting member.

Abstract: An image fixing apparatus stably maintains high efficiency in heat generation and reduces loss of electric power consumption for fixing an image, which includes a coil member to generate a magnetic flux, a heat member to generate heat with the magnetic flux, and a support member to support the coil member so that the coil member faces a front and a back side of the heat member, wherein the support member includes a heat dissipation part that releases heat generated in the coil member.

Abstract: A fixing apparatus 50 capable of reducing noise during a fixing operation using a fixing belt 1 having a metal layer includes the fixing belt 1 stretched between a fixation roller 2 and a fixation tension roller 3. The fixing apparatus 50 further includes a coil 4b which is disposed opposite from the fixation tension roller 3 via the fixing belt 1 and is supplied with an AC (600 V, 25 kHz at maximum) by an IH controller 10, so that the fixing belt 1 and the fixation tension roller 3 are simultaneously heated by induction heating. In the fixing apparatus 50, insulating belt flanges 25a and 25b are attached to the fixation tension roller 3 at both end portions of the fixation tension roller 3 to limit movement of the fixing belt 1 in a width direction of the fixing belt 1.

Abstract: Embodiments herein include a media conditioning module for being connected between a media source supplying sheets of media and a printing device. The media conditioning module is adapted to remove moisture from the sheets of media received from the media source before the sheets of media are supplied to the printing device. The media conditioning module comprises a heater and a cooler. The heater has manifolds positioned to supply heated air to both sides of the sheets of media as the sheets of media pass through the media conditioning module. The cooler is positioned to supply non-heated air to both sides of the sheets of media as the sheets of media pass through the media conditioning module. The heater is positioned with respect to the cooler such that the sheets of media pass by the heater before the sheets of media pass by the cooler.

Abstract: An image heating apparatus includes a plurality of heater element groups each having a plurality of heater elements. The heater elements are arranged along a direction intersecting an advancing direction of a recording material, and generate heat upon energization to heat a toner image on the recording material. A detecting mechanism is provided for detecting an abnormal state of the heater groups.

Abstract: A process chamber of an installation for the thermal treatment of printed circuit boards is described. The process chamber may include a fan wheel supported on a shaft parallel to the printed circuit boards, the fan wheel being disposed between two walls of the process chamber. The fan wheel is open at its two end faces and the two end faces are at such a distance from the walls of the process chamber that gas flows in unimpeded in two substreams between the end faces of the fan wheel and the walls and flows out from the cylindrical surface of the fan wheel over the length thereof and in the extent of the process chamber in the form of a ribbon-shaped gas stream, the gas stream being directed essentially in the cross section through a channel onto the printed circuit boards.

Abstract: A fixing device (23) of the present invention includes a fixing roller (131) contacting a toner image surface, and a pressure roller (132) contacting a surface opposite to the toner image surface. In the fixing device (23), a printing sheet (P) on which unfixed toner image is formed passes through a fixing nip portion (Y) where the fixing roller (131) and the pressure roller (132) are in contact with each other, so that the above-described toner image is fixed on the printing sheet (P). The fixing device (23) further includes a control circuit (150) which controls heater lamps (134 to 136) so that a surface temperature of the pressure roller (132) is in a temperature range defined by a cold offset occurring boundary temperature (Thc) of the fixing roller (131) and/or a hot offset occurring boundary temperature (Thh) of the fixing roller (131).

Abstract: A roll useful in fusing marking material to a print sheet includes a coating disposed on at least a portion of the inner surface thereof. A lamp disposed inside the roll supplies radiant energy to the inner surface. The coating changes its absorptivity (such as color) as desired, to obtain specific desired temperatures at different portions of the roll. The coating can be thermochromic, changing its absorptivity in response to local temperature; or electrochromic, changing its absorptivity in response to an external electrical stimulus.

Abstract: A fixing apparatus of an image forming apparatus of the present invention, in arrival timing of a temperature falling area of a heat roller passing a nip at opposite position ? of an induction heating coil from temperature detection position ? by an infrared temperature sensor around the heat roller, according to detection results by the infrared temperature sensor, controls an output value of the induction heating coil under control of an inverter circuit, heats and returns the heat roller in real time to a fixable temperature, and realizes energy conversation. At the time of arrival at the nip, the heat controller is always set to a fixed fixable temperature, thus in a fixed image, a high image quality free of ripple marks can be obtained.

Abstract: The present invention relates to an image thermal apparatus including a flexible metallic sleeve, the inner peripheral surface of which contacts a heater. In order to provide increased durability for the sliding face of the heater, an imide resin that contains silicon nitride elementary particles is used to coat the sliding face of the heater.

Abstract: An image forming apparatus includes a fixing unit for fixing a toner image on a recording sheet. In the fixing unit, a magnetic flux generator generates magnetic flux to induce heat in a fixing roller. The recording sheet having the toner image is inserted between the fixing roller and a pressure roller pressingly contacting the fixing roller. The fixing roller applies heat to the recording sheet. The pressure roller applies pressure to the recording sheet. The heat and pressure fix the toner image on the recording sheet. The magnetic flux generator is disposed to face outer and inner circumferential surfaces of the fixing roller. The magnetic flux generator is formed in a U-like or loop-like shape, and the fixing roller is placed in a gap or a loop of the magnetic flux generator. The magnetic flux generator may include a single wire.

Abstract: Provided is a printing device comprising a hot roller having an inside surface and an outside surface. A heating element is present within the hot roller. The inside surface has a first region, wherein the first region is coated with a first type of material. The inside surface has a second region, wherein the second region is coated with the first type of material, and wherein second region is of a different dimension than the first region. The inside surface has a third region, wherein the third region is coated with a second type of material.

Abstract: A fixing device includes a cylindrical fixing roller, an endless belt and a pressure member. The endless belt rotates along with the fixing roller. The endless belt is disposed at a position facing the fixing roller. The pressure member is disposed inside the endless belt. The pressure member pressurizes the fixing roller via the endless belt. The pressure member includes a contact member and an adjustment member. The contact member directly contacts with the endless belt. The adjustment member adjusts distribution of pressure given to the contact member.

Abstract: The heating apparatus of a surface-heating type, includes a rotary member, an opposing member that forms a nip with respect to the rotary member, and a heating member for heating a portion of a rotary member surface other than the nip, in which temperature used for heating the rotary member by the heating member is controlled, and a heating material inserted in the nip to be nipped and conveyed therein is heated using heat of the rotary member. Accordingly, after insertion of the heating material in the nip starts, control temperature of the heating member is increased before the rotary member rotates by one revolution, thereby preventing an uneven heating phenomenon of the heating material in the first revolution and the second revolution or later, and preventing uneven gloss due to the uneven heating phenomenon in the fixing apparatus.

Abstract: This is a pre-heater system especially useful in an electrostatic marking apparatus. It is used to heat the toner and paper (media) prior to the paper entering the conventional fuser station. Using this pre-heater increases fusing productivity (ppm), widens media latitude and/or extends fuser member life for a given fuser system. It also dramatically improves uniform heat transfer and paper handling problems encountered in prior art preheat fusing assemblies. The preheater is used together with the conventional fuser stations used today in electrostatic marking systems.

Abstract: A toner-fixing heater includes a substrate elongated in a first direction, a resistor formed on the substrate, a wiring portion connected with the resistor, and a protective film covering the resistor. The resistor includes two belt-like portions elongated in the first direction and spaced away from each other in a second direction perpendicular to the first direction. The resistor or the wiring portion includes a conductive portion for passing an electric current in the second direction. The conductive portion may have an edge extending in nonparallel to the first direction and the second direction, or may include a first layer and a second layer formed on the first layer, where the first layer is closer to the substrate than the second layer, and the edges of the second layer are located inward of the edges of the first layer as viewed in the first direction.

Abstract: An image forming apparatus, including a heat roller in which a heating source is embedded, a press roller installed close to the heat roller, the press roller contacting the heat roller with a predetermined pressurizing force to form a fixing nip, and at least two overheat prevention devices installed near the heat roller to cut off a power supply to the heating source upon an overheating of the heat roller. One of the overheat prevention devices is installed at portion of the heat roller corresponding to a location within a width of a recording medium passing through the fixing nip and another is installed at a site near an end of the heat roller corresponding to a location outside the width of the recording medium.

Abstract: A fuser includes a magnetic flux generation unit to generate a magnetic flux, a heating member which is heated by electromagnetic induction of the magnetic flux, a fuser member to contact the heating member and heat a toner image so as to fuse the toner image onto a recording medium, a detection unit to directly or indirectly detect a contacting state of the fuser member at an edge in a width direction of the fuser member with the heating member, and a magnetic flux adjusting member to reduce the magnetic flux acting upon an end in the width direction of the heating member in accordance with a detection result of the detection unit.

Abstract: A MEMS vapour bubble generator that uses a heater in thermal contact with a liquid to generate a bubble. The heater is energized by an electrical pulse that is shaped to have a relatively low power, sub-nucleating portion and a high power portion that nucleates the bubble. The thermal energy transferred to the liquid by the sub-nucleating portion speeds up the nucleation of the bubble across the surface of the heater during the nucleating portion. This produces larger, more stable bubble having a regular shape.

Abstract: A heating and fixing device for toner particles is provided, which includes a pressing element, at least one elastic element, a tube-shaped film, and a pressing roller. The elastic element is provided for generating force to press the pressing element constantly. The heating element is provided for heating the pressing element through the heated side. The film is disposed around the pressing element and the heating element, wherein the film slides relative to the pressing element, and the pressing element presses against the film from the inner side of the film and transfers heat to the film by heat conduction. The pressing element presses the film to contact the pressing roller, so that the recording medium is pressed and heated when traveled between the pressing roller and the film.

Abstract: In a fixing apparatus capable of reducing unevenness in temperature distribution in an axial direction while reducing heat loss at an end portion, a fixing belt 11 extended around a fixation roller 13 and a fixation tension roller 14 is heated by a coil unit 28 for effecting induction heating. The fixation tension roller 14 is assembled by inserting a heat pipe 15 into a hollow roller 14a. At both end portions, the hollow roller 14a is covered with a cover portion having small holes.

Abstract: A method of controlling a phase of an alternating current (AC) power having an AC voltage waveform having a predetermined cycle includes counting a number of times a zero crossing signal has been generated, the zero crossing signal being generated whenever a level of the AC voltage waveform becomes “0”; calculating a half cycle of the AC voltage waveform based on times at which the counted number of times the zero crossing signal has been generated changes; detecting phases that divide an area surrounded by a waveform corresponding to the half cycle of the AC voltage waveform into a predetermined number of equal areas; and generating control pulse signals based on the detected phases

Abstract: An internal heating system for an image transfer drum is disclosed that can include a box having a plurality of sides, an open side facing the drum and a heater element. The box can have small gaps between it and the internal drum surface to maximize thermal efficiency of the internal heating system. The heater element can include first and second support structures that are disposed on a central support structure, the first support structure having an end connector at one side away from the second support structure. The heater system can also include at least two circuits, two channels and a relay switch, with the relay switch operating to switch the circuits into a series or parallel electrical configuration.

Abstract: A roll useful in fusing marking material to a print sheet includes a coating disposed on at least a portion of the inner surface thereof. A lamp disposed inside the roll supplies radiant energy to the inner surface. The coating changes its absorptivity (such as color) as desired, to obtain specific desired temperatures at different portions of the roll. The coating can be thermochromic, changing its absorptivity in response to local temperature; or electrochromic, changing its absorptivity in response to an external electrical stimulus.

Abstract: An excitation coil unit for use in an image heating apparatus includes a coil formed with a conductor without an insulation covering and a heat-resistant insulating material covering the coil. It is thus possible to obtain an image heating apparatus of induction heating type of a low cost.

Abstract: An embodiment of an air heating apparatus includes a mass to store heat energy and a heater to provide the heat energy to the mass.

Abstract: A fixing apparatus and an image formation apparatus therewith are disclosed. According to the fixing apparatus, a heating range that is heated by electromagnetic induction caused by a current flowing through a coil unit is finely tunable by covering a part of a core unit with a shielding member. Further, the core unit has a projecting section at an end of the core unit, which projecting section projects toward the coil unit in comparison with the central part of the core unit.

Abstract: A fusing device (23) has heat reflectors (238) and (239) positioned in consideration of the fact that convective heat loss from respective outer surfaces of the heat reflectors (238) and (239) depends on orientation of the outer surfaces. More specifically, each of the heat reflectors (238) and (239) are positioned so as to have a convective heat transfer coefficient ? of up to 0.9. The convective heat transfer coefficient ? is given by the following expression: ?=(Su+0.77Sh+0.54Sd)/(Su+Sh+Sd), were Su is a projected area of an outer surface of each of the heat reflectors on an upper horizontal plane, Sh is a projected area of the same on a vertical plane, and Sd is a projected area of the same on a lower horizontal plane.

Abstract: A fixing device for fixing a toner image onto a recording medium, and an image forming apparatus having the same are provided. The fixing device includes a fixing roller heated by a heating source, and a pressing unit disposed opposite the fixing roller to bias a recording medium towards the fixing roller so that the recording medium contacts the fixing roller. The pressing unit has a movable support member, a pressing member mounted at the support member to face the fixing roller, a pressing belt rotatably disposed around the support member and the pressing member and biased by the pressing member to form a nip with the fixing roller, a driving roller for rotating the pressing belt, and a resilience applying member for biasing at least one of the support member and the driving roller toward the fixing roller. Accordingly, the pressing unit basically expands the width of the fixing nip to improve the image fixing capability.

Abstract: An image heating apparatus includes magnetic flux generating means; a rotatable heat generation member for generating heat by a magnetic flux generated by the magnetic flux generating means to heat a recording material; a magnetic flux adjusting member, disposed between the magnetic flux generating means and the heat generation member, for adjusting a magnetic flux effective region for the heat generation member, with respect to a longitudinal direction which is perpendicular to a feeding direction of the recording material; moving means for moving the magnetic flux adjusting member to a predetermined magnetic flux adjusting position to adjust a temperature distribution of the heat generation member with respect to the longitudinal direction; and a drive receiving portion, disposed at opposite end portions of the magnetic flux adjusting member, for receiving a driving force from the moving means.

Abstract: An induction heating device of the invention is made to have a two-layer structure in which at an end of a magnetic core of an induction current generating coil, a litz wire of outside three turns is stacked on a litz wire of inside three turns. The width of a joint portion between plural induction current generating coils is made narrow, and a mutual induction current generated at the joint portion is reduced. Further, the whole length of the litz wire is shortened without changing the length of the magnetic core of the inductor current generating coil.

Abstract: Methods and apparatus for performing addressable fusing and/or heating of a substrate undergoing xerographic processing are disclosed. The apparatus includes a fuser having an array of addressable heating elements in radiative communication with a substrate through a fuser roll or fuser belt. The array of addressable heating elements is operated to selectively heat portions of the substrate to achieve a desired effect on the substrate, such as changing its surface finish, or fusing unfused toner to the substrate. In the case of toner fusing, the array is operated such that substantially only an area covered by the unfused toner is heated. This eliminates the need for blanket fusing, and generally provides for greater flexibility in xerographically processing substrates. Apparatus and methods for performing two-sided selective fusing and/or heating are also disclosed.

Abstract: An image heating apparatus has a coil for generating magnetic flux, a rotatable heat generation member which generates heat by magnetic flux, a temperature detecting member for detecting a temperature of the heat generation member, an energization controller portion for controlling energization to the coil on the basis of an output of the temperature detecting member, a first magnetic flux shielding portion for blocking, in a first magnetic flux adjustment position, the magnetic flux directed toward a central portion of heat generation member, while permitting the magnetic flux directed to an end portion, and a second magnetic flux shielding portion for blocking, in a second magnetic flux adjustment position, the magnetic flux directed toward an end portion of the heat generation member, a moving unit for moving the first magnetic flux shielding portion and the second magnetic flux shielding portion, and a recovery operation controller portion for retracting the second magnetic flux shielding portion from the

Abstract: A fixing device 100 includes a fixing belt 102, a heat source 105, a support member 104, a pressure roller 103, and a reinforcing member 106. The fixing belt 102 has a metal sleeve. The heat source 105 is provided within the fixing belt 102. The support member 104 has a contact surface 104a that is in sliding contact with the inside surface of the fixing belt 102. The pressure roller 103 forms a nip with the bottom surface 104a between which the fixing belt 102 is sandwiched and pressed. The pressure roller 103 drives the fixing belt 102 to rotate. The reinforcing member 106 has a surface contacting the support member 104 on which a plurality of irregularities is formed. The reinforcing member 106 is positioned on a side opposite the support member to the bottom surface 104a, and receives a pressure force applied by the pressure roller 103.

Abstract: A paper clip removing device capable of removing a paper clip made of a shape memory alloy, that has such a shape that a plurality of documents are bound at a normal temperature and a document bundle is released in a heated state, when the paper clip is on any positions on an end side of a document is provided. When a paper clip made of a shape memory alloy, that has such a shape that a plurality of documents are bound at a normal temperature and a document bundle is released in a heated state, is removed, the paper clip removing device detects a position of the paper clip to heat the paper clip and deforms the paper clip into a shape of releasing a document bundle to attract and remove the paper clip, resulting that the paper clip is collected in the collecting box.

Abstract: A portable electrofusion machine includes: a power supply circuit having a triac configured to have a proper regulation for dropping a commercial voltage to a voltage adapted for a fitting; and a printer unit integrated with the electrofusion unit, for printing information regarding a work result of the fitting. According to the above construction, since the electrofusion machine does not use a transformer occupying 40% of a total weight of the machine, the mobility and portability are enhanced. Also, since the size of the machine is reduced, it is advantageous to deal with the machine on the spot.

Abstract: A fixing apparatus and an image formation apparatus are disclosed. The fixing apparatus includes two or more heaters with temperature detecting function that generate heat with electric current and detect temperature; a heating unit that includes the heater with the temperature detecting function; a film, a surface of which slides on the heating unit; a thermal fixing unit that is heated by the heating unit through the film for fusing a toner image that is yet-to-be fixed on a recording paper at a predetermined fixing temperature; a pressurization roller for pressing the recording paper to the thermal fixing unit; and a temperature control unit for controlling the temperature of the heater to be a predetermined temperature based on the temperature of the heater detected by the heater with the temperature detecting function.

Abstract: A fixing device includes an excitation coil, a heat-generating layer, a magnetic shunt layer, and a degaussing member. The excitation coil generates a magnetic flux. The heat-generating layer generates heat using the magnetic flux generated by the excitation coil. The magnetic shunt layer transmits heat generated by the heat-generating layer. The degaussing member sandwiches the magnetic shunt layer together with the excitation coil, and selectively performs degaussing by generating a repelling magnetic flux for canceling the magnetic flux generated by the excitation coil so as to activate a self-temperature-control function. The degaussing member selectively refrains from degaussing so as to deactivate the self-temperature-control function.

Abstract: A heating device includes a magnetic field generating unit, and a heat generating body having a heat generating layer generating heat due to electromagnetic induction, and a temperature-sensitive layer. The heat generating layer is disposed opposing the magnetic field generating unit. The temperature-sensitive layer has a Curie temperature greater than or equal to a set temperature of the heat generating layer and less than or equal to a heat-resistant temperature of the heat generating layer, and is disposed at a side of heat generating layer opposite a side where the magnetic field generating unit is disposed such that heat from the heat generating layer is conducted. At temperatures lower than the Curie temperature, the temperature-sensitive layer causes the magnetic field to penetrate in from the heat generating layer, and at temperatures greater than or equal to the Curie temperature, causes magnetic flux of the magnetic field to pass therethrough.

Abstract: In an image forming apparatus including a fixing device that uses a pressure belt as at least one of two pressing members, a warm-up time and time for shifting to a standby state are reduced with simple control without increasing power consumption. The two pressing members are brought into a press-contact state by a contacting/separating mechanism and only heating means on the upper side is turned on. When the temperature of the upper pressing member increases to temperature near a target temperature corresponding thereto, the pressing members are driven to rotate. When it is detected by temperature detecting means on the lower side that the temperature of the lower pressing member increases to temperature near a target temperature corresponding thereto, the two pressing members are brought into a separated state by the contacting/separating mechanism.

Abstract: An image printer using a common filter to remove harmonic waves generated at a common operating frequency band of a fixing module to fix toner onto a print medium using high frequency power generated from a high frequency generator and a switch mode power supply module to supply operating power to the high frequency generator. The image printer includes a fixing module to fix toner to a print medium using high frequency power generated from a high frequency generator, a switch mode power supply module to supply operating power to the high frequency generator, and a band pass filter to filter harmonic waves of a common operating frequency band of the fixing module and the switch mode power supply module.

Abstract: A heating device of the invention comprises a heater, a main power supply, and an auxiliary power supply. The heater includes a main heating element which generates heat with power supplied from the main power supply, and an auxiliary heating element which has a resistance different from a resistance of the main heating element and generates heat with power supplied from the auxiliary power supply. The auxiliary power supply is provided to supply to the auxiliary heating element a current that is different from a current supplied from the main power supply to the main heating element.

Abstract: An image forming apparatus includes a fixing unit for fixing a toner image on a recording sheet. In the fixing unit, a magnetic flux generator generates a magnetic flux to induce heat in a support roller. The heat is transferred to a fixing belt contacting the support roller. The recording sheet having the toner image is inserted between the fixing belt and a pressure roller facing the fixing belt. A holder holds the magnetic flux generator and positions the magnetic flux generator to face outer and inner circumferential surfaces of the support roller.

Abstract: A heat roller for a laser printer has a roller pipe, a resistive heat element accommodated in the roller pipe, an internal expanding pipe installed in the roller pipe which restricts the resistive heat element by pushing the resistive heat element toward the roller pipe, caps coupled to both end portions of the internal expanding pipe and provided with electrodes which supply a current to the resistive heat element, a gear coupled to any one of the caps, and a coupling unit which restricts at least one of the caps from slipping along the internal expanding pipe. The heat roller has the enhanced secure coupling between the internal expanding pipe, the roller pipe, the coil and the insulation layer. Accordingly, it is possible to prevent slip off and coil short circuit.

Abstract: The invention relates to an apparatus for power control by phase gating of an AC voltage, which supplies an electrical load (14), and for reduction of harmonics which are created by the phase gating, in particular up to a region of 4 kHz, preferably in the region of the third harmonic, having a first circuit element (12) (TRIAC) which is connected in series with the load (14) and is driven by a control device (20) in order to carry out phase gating. The apparatus is distinguished in that a second circuit element (34) is provided in series with a resistance element (32), with the series circuit being arranged in parallel with the first circuit element (12) and with the control device (20) being designed such that it drives the second circuit element (34) shortly before the first circuit element (12) and switches it to the on state for a short time period. The invention also relates to a method for harmonic reduction in the range up to 4 kHz, preferably of the third harmonic, for power control by phase gating.

Abstract: The present invention includes: a printing portion (12) for performing printing on a printing layer of a sheet material (5) including a sheet-like base having one surface provided with the printing layer and another surface provided with a heat-sensitive adhesive layer; a thermal activation portion (15) for heating the heat-sensitive adhesive layer of the sheet material (5) and generating an adhesive force; a temporary stock portion (14), which is disposed in a transport path for the sheet material (5) between the printing portion (12) and the thermal activation portion (15), for temporarily stocking the sheet material (5); and a casing (19) covering the temporary stock portion (14).

Abstract: In a fixing device for causing a pressurizing roller to come in pressure contact with a heating roller including a central region heating heater for heating a central region and a side end region heating heater for heating a side end region on an outside of the central region, thereby fixing an unfixed toner, or an image forming apparatus comprising the fixing device, an outside of an image region of the heating roller is caused to have a peak of heat distribution of the central region heating heater and heat radiated from both side ends of the heating roller is compensated to flatten the temperature distribution of the image region, thereby preventing a deterioration in an image.

Abstract: A disclosed fixing device includes: a heat roller unit having a rotatable roller having an elastic body on a surface thereof and a heating unit heating the roller; a pad disposed along a circumference of the elastic body of the heat roller; a belt member disposed on a curved surface of the pad, the belt member rotating by following a rotation of the heat roller; and a pressure member pressing the belt member to the heat roller using the pad, the fixing device causing a conveyed recording medium carrying a visualized image to pass through a space between the heat roller and the pressure member so as to fix the visualized image on the recording medium, wherein a curvature of the curved surface of the pad is changed in a central portion and end portions in an axial direction of the heat roller.