Abstract: A fixing apparatus of one embodiment of the present invention has a heating member which is heated by induction heating, a pressing member which supplies a predetermined pressure to the heating member, and induction heating mechanisms which supply a predetermined magnetic field to the heating member. The induction heating mechanisms have a plurality of coils. By arranging the adjacent coils and adjacent coils to overlap, the temperature distribution in the length direction of the heating member can be made uniform.

Abstract: The present invention is in the field of electrophotographic printers and copiers. More specifically this invention relates to the fuser apparatus used to fuse an image on a receiving sheet. According to just one aspect of the invention, an apparatus and process for fixing toner images to a receiving sheet is provided. The apparatus may include a fuser having a run condition and an idle condition, the fuser having a fuser roller, a fuser roller heater, and a fuser temperature sensor which inputs to a logic and control system which controls the heating of the fuser roller heater. The fuser roller may be cooled during or after the idle condition, prior to the first receiving sheet entering the fuser. The fuser roller has end portions and a middle portion, and the middle portion may be cooled relative to said end portions. Additional aspects and representative embodiments are described herein.

Abstract: The invention relates to the use of roller fusing in printing. In particular, the invention relates to the use of heated rollers. According to one aspect of the invention, a fixing process and system for use with a printing apparatus is provided wherein a flow of heat exchange medium through a first heating zone within a fixing roller and a second heating zone within the fixing roller is controlled, and marking material is fixed to a receiver with the fixing roller. According to another aspect of the invention, a fixing process and system for use with a printing apparatus is provided wherein marking material is fixed to a receiver with a fixing roller and wherein a heat exchange medium is flowed through a first heating zone within the fixing roller, the first heating zone being biased toward the receiver.

Abstract: A heat roller having a cylindrical sheet-like heating element having a resistance member embedded into an insulating member. The sheet-like heating element is arranged between an inner tube and an outer tube. The resistance member is formed such that a heating density of the sheet-like heating element is changed in an axial direction of the heat roller. The heating density of the sheet-like heating element at its edge section is greater than that at a center in the axial direction of the heat roller.

Abstract: A heating apparatus has an excitation coil; magnetic flux generator having a magnetic member core, the magnetic member core having a first magnetic core supported with a holder for the excitation coil and a rotatable second magnetic member core; an induction heat generating element for electromagnetic induction heat generation using the magnetic flux generated by the magnetic flux generator; a heating portion for receiving a recording material and for heating the recording material by the heat generated by the induction heat generating element; and a rotator for rotating second magnetic core to a different angular position to change a heat generation distribution in a longitudinal direction of the induction heat generating element.

Abstract: A heating apparatus includes first and second coil members, a heat roller and an input control mechanism. The first and second coil members respectively are part of first and second excitation circuits. The heat roller generates an eddy current inside by a magnetic field generated by the first and second coil members. The input control mechanism drives the first and second excitation circuits. The input control mechanism starts driving only the first excitation circuit from a state where operations of the first and second excitation circuits are stopped. When the temperature detection mechanism detects a predetermined temperature, the input control mechanism stops supplying power to the first excitation circuit and supplies power only to the second excitation circuit, and the heat roller initiates rotating.

Abstract: A heating device for heating a recording sheet. The heating device has a first heater located within a heating roller. The first heater has a heat distribution effective to form a low temperature region in an axially central portion of the heating roller and a high temperature region in each of axially opposite end portions of the heating roller. There is a second heater located within the heating roller that has a heat distribution effective to form a high temperature region in the axially central portion of the heating roller, a low temperature region in each of the opposite end portions of the heating roller, and a second-level high temperature region in each of axially opposite end portions of the high temperature region, the second-level high temperature region being lower in temperature than the high temperature region.

Abstract: A thermal fixing device is equipped with a plurality of heaters for heating a fixing member at different axial positions thereof for proper temperature control. When the difference between the center temperature TA and the end temperature TB exceeds a proper temperature difference range (15° C.), of the center temperature TA and the end temperature TB, the one nearer to the average temperature Tm of the fixing upper limit temperature Th and the fixing lower limit temperature T1. is selected. The control value for the farther halogen lamp is changed so as to approach the selected temperature. When the temperature difference is 10° C. or less, the control value is further changed. With this process, it is possible to set both the temperatures and the portion near the center of the thermal roller to temperatures within the proper temperature range.

Abstract: A heating apparatus has an excitation coil; magnetic flux generator having a magnetic member core, the magnetic member core having a first magnetic core supported with a holder for the excitation coil and a rotatable second magnetic member core; an induction heat generating element for electromagnetic induction heat generation using the magnetic flux generated by the magnetic flux generator; a heating portion for receiving a recording material and for heating the recording material by the heat generated by the induction heat generating element; and a rotator for rotating second magnetic core to a different angular position to change a heat generation distribution in a longitudinal direction of the induction heat generating element.

Abstract: An image fanning apparatus is provided with a pressing roller for pressing a sheet at the time of a fixing operation; a fixing roller having a hollow portion, facing the pressing roller, rising in temperature by being heated, and fixing a developer to the sheet by sandwiching the sheet between the fixing roller and the pressing roller; and induction heating coils including a center-section coil and an end-section coil, and arranged inside the fixing roller in an axial direction so as to leave a space between the center-section coil and the end-section coil, the space being adjusted so that the temperature of one surface of the fixing roller, the one surface opposing the space, is not higher than the temperatures of the other surface of the fixing roller, the other surface opposing central portions of the coils.

Abstract: A fixing roller and a pressure roller form a nip therebetween to fix a recorded image onto a recording sheet provided into the nip. A coil provides alternating magnetic field with respect to the fixing roller to inductively heat the fixing roller. The coil includes a plurality of coil segments arranged in an axial direction of the fixing roller. The coil segments are connected in a manner of either forward connection or alternate connection. A controller determines either the forward connection or the alternate connection such that an heating efficiency due to the induction heating has a larger value.

Abstract: A printer fuser with a plurality of separately powerable heating zones along its length for permitting variably controllable heat application to a medium.

Abstract: An induction heat fixing device has coil portions with electric wires wound around the outer surface of a cylindrical main bobbin, grooves and flanges formed at both ends of the main bobbin. Further, plural ribs are formed in the main bobbin. The main bobbin is put into a holder with these ribs brought in contact with the holder.

Abstract: An induction heating roller apparatus has a heating roller capable of switching among a plurality of heating areas of different lengths according to a size of an object to be heated, a plurality of first induction coils opposed to a plurality of heating areas of the heating roller, and second induction coils placed opposite a part astride adjacent heating areas of the heating roller. A high frequency power supply provides high frequency power to the first and second induction coils. High frequency output is selectively supplied to the first induction coils and the second induction coils.

Abstract: A fixing apparatus of one embodiment of the present invention has a heating member which is heated by induction heating, a pressing member which supplies a predetermined pressure to the heating member, and induction heating mechanisms which supply a predetermined magnetic field to the heating member. The induction heating mechanisms have a plurality of coils. By arranging the adjacent coils and adjacent coils to overlap, the temperature distribution in the length direction of the heating member can be made uniform.

Abstract: A printer fuser with a plurality of separately powerable heating zones along its length for permitting variably controllable heat application to a medium.

Abstract: A heating apparatus includes first and second coil members, first and second temperature detectors and an output controller. The detectors detect temperatures of the coil members. The output controller supplies the first coil member with a first specified output until the first temperature detector detects that the first coil member heats the object. The second coil member is not supplied with a second specified output during this time. When the object reaches a specified temperature, the first specified output stops being supplied to the first coil member and the second specified output is supplied to the second coil member. The temperature of an area heated by the second coil member reaches a specified temperature. A comparison is made between temperatures detected by the first and second temperature detectors. The coil members are alternately supplied with first and second specified outputs to heat the object's area indicating a lower temperature.

Abstract: An image forming apparatus is provided with a pressing roller for pressing a sheet at the time of a fixing operation; a fixing roller having a hollow portion, facing the pressing roller, rising in temperature by being heated, and fixing a developer to the sheet by sandwiching the sheet between the fixing roller and the pressing roller; and induction heating coils including a center-section coil and an end-section coil, and arranged inside the fixing roller in an axial direction so as to leave a space between the center-section coil and the end-section coil, the space being adjusted so that the temperature of one surface of the fixing roller, the one surface opposing the space, is not higher than the temperatures of the other surface of the fixing roller, the other surface opposing central portions of the coils.

Abstract: An image forming apparatus is provided with a pressing roller for pressing a sheet at the time of a fixing operation; a fixing roller having a hollow portion, facing the pressing roller, rising in temperature by being heated, and fixing a developer to the sheet by sandwiching the sheet between the fixing roller and the pressing roller; and induction heating coils including a center-section coil and an end-section coil, and arranged inside the fixing roller in an axial direction so as to leave a space between the center-section coil and the end-section coil, the space being adjusted so that the temperature of one surface of the fixing roller, the one surface opposing the space, is not higher than the temperatures of the other surface of the fixing roller, the other surface opposing central portions of the coils.

Abstract: An image forming apparatus which includes a fixing device including a fixing roller, a pressure roller pressed into contact with the fixing roller, and a thermistor in contact with a non-paper-passage region on the surface of the fixing roller, the fixing roller incorporating a first halogen heater whose heat distribution based on the axial direction of the fixing roller is set such that heat in a middle region thereof is higher than heat in opposite-end regions thereof, and a second halogen heater whose heat distribution based on the axial direction of the fixing roller is set such that heat in opposite-end regions thereof is higher than heat in a middle region thereof; and a controller for controlling power supply to the first and second halogen heaters. The controller starts power supply to the first and second halogen heaters to start warm-up of the fixing device, and cuts off power supply to the first halogen heater for a predetermined period of time during the warm-up.

Abstract: A heating apparatus includes first and second coil members, first and second temperature detectors and an output controller. The detectors detect temperature of the coil members. The output controller supplies the first coil member with a first specified output until the first temperature detector detects that the first coil member heats the object. The second coil member is not supplied with a second specified output during this time. When the object reaches a specified temperature, the first specified output stops being supplied to the first coil member and the second specified output is supplied to the second coil member. The temperature of an area heated by the second coil member reaches a specified temperature. A comparison is made between temperatures detected by the first and second temperature detectors. The coil members are alternately supplied with first and second specified outputs to heat the object's area indicating a lower temperature.

Abstract: An image fixing apparatus has a magnetic field generating unit for generating a magnetic flux; a heating member generating heat by induction heating by the magnetic flux generated by the magnetic field generating unit; and a blocking plate, disposed for movement between the magnetic field generating unit and the heating member, for blocking the magnetic flux from the magnetic field generating means, wherein the blocking plate comprises an electroconductive member having a thickness of 0.1-2 mm.

Abstract: A apparatus and method for fusing toner to media in a laser imaging device. A paraboloidal trough reflector is positioned about a linear heating element to focus and concentrate radiant energy emitted from the heating element onto a thermal spreader. The thermal spreader absorbs the radiant energy and converts it to heat. A thermoplastic fusing roller is rotatably supported about the bulb heater, the reflector and the thermal spreader. A pressure roller is supported to urge media against the fusing roller at the position of the thermal spreader. Fusing heat is conducted from the thermal spreader, through the fusing roller and to the media. The pressure roller is driven to rotate, thereby advancing the media through the fusing unit to fuse the toner thereto. Additionally, the present teachings disclose a printing device having a fusing unit with a bulb heater that emits user non-perceivable light. A mechanism is included for conveying light from the bulb heater to a location within the printing device.

Abstract: The invention concerns the image forming apparatus incorporating a fixing unit, which is includes either a fixing belt or a fixing roller, and effectively used in a copier or a printer. The fixing unit includes a fixing belt threaded on a plurality of supporting rollers and a temperature-equalizing member to equalize a temperature distribution of the fixing belt in its width direction. The temperature-equalizing member moves from a separate position to a first pressure-contacting position at which the temperature-equalizing member pressure-contacts the fixing belt, and further moves to a second pressure-contacting position while maintaining a pressure-contacting state with the fixing belt. A contact area of the temperature-equalizing member and the fixing belt is enlarged at the second pressure-contacting position, compared to that at the first pressure-contacting position. The temperature-equalizing member can park at either the first pressure-contacting position or the second pressure-contacting position.

Abstract: An image forming apparatus comprising: a fixing device including a fixing roller, a pressure roller pressed into contact with the fixing roller, and a thermistor in contact with a non-paper-passage region on the surface of the fixing roller, the fixing roller incorporating a first halogen heater whose heat distribution based on the axial direction of the fixing roller is set such that heat in a middle region thereof is higher than heat in opposite-end regions thereof, and a second halogen heater whose heat distribution based on the axial direction of the fixing roller is set such that heat in opposite-end regions thereof is higher than heat in a middle region thereof; and a controller for controlling power supply to the first and second halogen heaters. The controller starts power supply to the first and second halogen heaters to start warm-up of the fixing device, and cuts off power supply to the first halogen heater for a predetermined period of time during the warm-up.

Abstract: Disclosed is a thermal fixing device equipped with a plurality of heaters for heating a fixing member at different axial positions thereof for proper temperature control. In S300, a judgment is made as to whether the difference between the center temperature TA and the end temperature TB exceeds a proper temperature difference range (15° C.) or not. When the difference exceeds the proper temperature range (S300: YES), the procedure advances to S310, where, of the center temperature TA and the end temperature TE, the one nearer to the average temperature TM of the fixing upper limit temperature Th and the fixing lower limit temperature T1 is selected. Subsequently, in S320, the control value for the farther halogen lamp is changed so as to approach the selected temperature. And, in S330, a judgment is made as to whether the temperature difference is 10° C. or less. When it is not 10° C. or less, the procedure returns to S320 to further change the control value.

Abstract: In a film heating system, since a heating body is in contact with the conductive ring at an end portion of the heating body, heat body through the conductive ring, with the result that the quantity of heat imparted to the object to be heated is uneven inside the nip. This causes low quality of an image since it leads to faulty end-portion fixing, uneven fixing and uneven glossy. In order to solve this problem, a heater capable of suppressing faulty image heating is provided.

Abstract: A digital printing or copying machine (1), and a process which can be carried out with it, for one-sided or double-sided printing of a substrate (5) using at least one toner are proposed. The machine (1) includes at least one fixing device (3) for fixing of a toner image (29) on the substrate (5), having at least one heater (21, 23) for melting the toner image (29), past which the substrate (5) can be guided by a transport device (11) which has one or more transport elements (29, 63 to 71). The machine (1) is characterized in that the heater (21, 23) has at least two melt areas (31, 33, 43 to 47) on the substrate (5) which viewed in the substrate transport direction (15) are arranged in succession and laterally offset to one another.

Abstract: An object of the present invention is to provide an image heating apparatus for heating an image formed on a recording material that has a heating member, and an excitation coil for generating a magnetic field to induce an eddy current in the heating member, the heating member having a magnetic metallic layer and a non-magnetic metallic layer, the coil being disposed on the magnetic metallic layer side of the heating member.

Abstract: A heating apparatus includes an excitation coil; magnetic flux generating means having a magnetic member core, the magnetic member care including a first magnetic core supported with a holder for the excitation coil and a rotatable second magnetic member core; an induction heal generating element for electromagnetic induction heat generation using the magnetic flux generated by the magnetic flux generating means a heating portion for receiving a recording material and for heating the recording material by the heat generated by the induction heat generating element; and rotating means for rotating second magnetic core to a different angular position to change a heat generation distribution in a longitudinal direction of the induction heat generating element.

Abstract: A fuser configured to fuse less than all of a printable area of a print medium passing there through, the fuser including an x-fuser and a y-fuser or a first fuser element for fusing one side of a print medium and a second fuser element for fusing another side of the print medium.

Abstract: A fixing device for fixing a toner image on a sheet, wherein the toner image is formed by a thermally meltable toner. The fixing device includes an induction heater to heat the toner image. The induction heater includes a hollow rotatable conductive member, a heating member provided inside the hollow rotatable conductive member, and a sendust layer provided inside the hollow rotatable conductive member. The fixing device also includes a pressing member to press the toner image.

Abstract: The present invention relates to any image heating apparatus which has a heating member and a coil for generating magnetic flux, and an eddy current is generated in the heating member by the magnetic flux generated by the coil, the heating member is heated by the eddy current, an image on a recording material is heated by the heat from the heating member, the coil is constituted by a litz wire obtained by twisting a plurality of insulation coated conductive wires, current of 5 Amperes to 50 Amperes are applied to the coil, and an outer diameter of each insulation coated conductive wire is selected to 0.01 mm to 0.4 mm.

Abstract: This invention provides a power supply device which widens a narrow output control width which is a drawback of a conventional voltage resonant power supply, and in adopting as a switching control element a low-cost IGBT (Insulated Gate Bipolar Transistor) which permits a large current, optimizes a gate signal waveform to minimize a switching loss in control because the IGBT has a larger loss than an FET. A voltage resonant converter includes a switching IGBT (201) connected to a power supply, a first resonant capacitor (204) series-connected to the IGBT (201), an IGBT (202) series-connected to the first resonant capacitor (204), an exciting coil (18) connected between the power supply and a node between the first resonant capacitor (204) and the IGBT (202), a second resonant capacitor (205) parallel-connected to the IGBT (202), and regenerative diodes (206, 207) respectively parallel-connected to the IGBTs (201, 202).

Abstract: A toner image fixing apparatus has a fixing roller, a pressing roller, and a heating roller. The pressing roller is normally urged toward the fixing roller for pressing a sheet with an unfixed toner image carried on a surface thereof against the fixing roller to fix the unfixed toner image to the sheet when the sheet passes in one direction through a rolling contact region between the fixing roller and the pressing roller. The heating roller is disposed on one side of the fixing roller opposite to the pressing roller. A first heat source is disposed in the heating roller for heating the heating roller, and a second heat source is disposed in the pressing roller for heating the pressing roller. An endless heat transfer belt is trained around the heating roller and the fixing roller for transferring heat from the first heat source to heat the unfixed toner image on the sheet when the sheet passes through the rolling contact region.

Abstract: There are provided three periods of time immediately after an AC power-supply voltage is started to be applied to fixing heaters when the heater temperature falls below a target temperature: a first period for driving only a first heater; a second period for driving only a second heater following the first period; and a third period for driving the first and second heaters following the second period. During the first and second periods, the first and second heaters are thinning-controlled, respectively. At this time, at a cycle of 3 half-waves of the AC voltage applied to each fixing heater, a thinning frequency is changed from a large value to a smaller one. The third period includes first and second sub periods which are alternately repeated. In at least one of the first and second sub periods, the first and second heaters are thinning-controlled and the relation of the thinning controls of the two heaters is such that they are complementary to each other on the time axis.

Abstract: The present invention provides an image heating apparatus which has a rotary member, magnetic flux generating device for generating a magnetic flux, and wherein an eddy current is generated in the rotary member by the magnetic flux generated by the magnetic flux generating device, the rotary member generates heat by the eddy current and an image on a recording material is heated by the heat, a heat conducting member being in contact with the rotary member, wherein, when, with respec to a direction perpendicular to a moving direction of the rotary member, Lh being a length of a heat generating region of the rotary member, Lf being a length of the rotary member, and L being length of the heat conducting member, Lh≦L≦Lf is satisfied.

Abstract: A thermally developing apparatus is provided with a heating device to heat a thermally developable material; a supplier for supplying the thermally developable material in a predetermined supplying direction to the heating device; the heating device having plural regions aligned in a direction substantially perpendicular to the supplying direction of the thermally developable material by the supplier; plural heaters each provided separately to one of the plural regions and to heat a corresponding one of the plural regions of the heating device; and a controller to control heat generation of the plural heaters, the controller controlling at least one of the plural heaters in accordance with a size of the thermally developable material which is a length substantially perpendicular to the supplying direction.

Abstract: A system for controlling axial temperature uniformity in a reproduction apparatus fuser device having at least one heated fuser member to permanently fix a marking particle image to a receiver member which may be of any of a variety of widths. The axial temperature uniformity control system includes a fuser member heater having at least one elongated heater lamp capable of exhibiting differing effective heating lengths. A logic and control unit is then provided to control the operation of said heater lamp to provide respective different effective heating lengths for different discrete modes of operation.

Abstract: The present invention relates to an image heating apparatus which has magnetic flux generating device, a heat generating body for electromagnetically inductively generating heat due to an operation of a magnetic flux generated by the magnetic flux generating device, a conductor provided so as to surround a part of the magnetic flux generated by the magnetic flux generating device, switching device which is connected to the conductor and which can form an electrically closed circuit by using the conductor, and control device for controlling an ON/OFF ratio of the switching device in accordance with a kind of a recording material.

Abstract: The present invention relates to an image heating apparatus in which an image on a moving recording material is heated by a heat from a heater, the heater has an elongated substrate extending in a direction perpendicular to a shifting direction of the recording material, and a first heat generating body and a second heat generating body for generating heat by energization and provided on the substrate along a longitudinal direction thereof, the first and second heat generating bodies are disposed side by side in a direction perpendicular to the longitudinal direction of the substrate, and the first heat generating body has a first heat generating portion, and a second heat generating portion provided at a longitudinal end of the first heat generating portion and having a heat generating amount per unit length smaller than that of the first heat generating portion, and, when the width of the recording material is detected to be smaller than a predetermined width by the detecting member, the first heat generati

Abstract: A thermal fixing device for thermally fixing an unfixed image carried on a record medium onto the record medium, including: a thermal fixing roller including a first resistance heating material layer (e.g.

Abstract: A rapid warm-up fuser roller (and fusers and marking machines that use such a fuser) comprised of a metallic cylindrical core, a thermally and electrically insulating layer of volume graft over the metallic core, a resistive heating layer over the insulating layer, and electrical connections to the resistive heating layer such that electrical current passing through the electrical connections flows through the resistive heating layer in a direction that is substantially parallel to the axis of the metallic core. The electrical current causes the resistive heating layer to heat while the insulating layer of volume graft enables rapid warm-up of the roller.

Abstract: A fuser hot roll for use in an electrophotographic process is disclosed. This roll is constructed such that the center portion of the roll's length has a greater thermal mass per unit length than each of the end portions of the roll's length. This can be accomplished either by constructing the center portion from a material which has a higher thermal capacity than the materials used for constructing the end portions, or constructing the center portion such that it is thicker than the end portions of the roll. The rolls of the present invention provide a simple way for regulating the fuser temperature such that it is uniform across the length of the hot roll, is uniform between the transitory (heat up) state and the steady state, and minimizes hot roll temperature overshoot during the transitory phase. The image fixing apparatus which incorporates this hot roll is also disclosed.

Abstract: In a heating roller for fixing which is constituted such that a heating resistor 3 is provided onto an inner circumferential surface 1a of a cylinder 1 with an insulating layer 2 lying therebetween and a cleavage layer 6 is provided onto an outer circumferential surface, electrical insulating properties of the insulating layer 2 are maintained satisfactorily for a long time.A maximum height (Rmax) of surface roughness of the inner circumferential surface 1a of the cylinder 1 is in the range of 0.8 to 50 .mu.m.A resistance value in the heating roller for fixing is partially adjusted easily.In a heating roller for fixing having a heater resistor 103 on a surface of a cylinder 101 with an insulating layer 102 lying therebetween, the heating resistor 103 is divided into a plurality of zones in an axial direction of the cylinder 101, and slots for adjusting resistance are formed in each zone.

Abstract: A low cost, compact heat roller device is provided which includes a heat generating resistance for increasing the temperature of the heat roller wherein the heat generating resistance is divided into two parts in order to correspond to passage widths of different recording materials. The heating power of one of these heat generating resistances is changed and the temperature increase of a non-paper transport area of the heat roller is suppressed. Specifically, the heat roller device includes a heat roller and a press roller opposite the heat roller, two heat generating resistances formed on an outer surface of the heat roller which generate heat independently of one another, a common electrode for supplying current and separately arranged additional supply electrodes. The time during which the respective heat generating resistance is on, is changed, in relative terms, according to the object to be heated, and thus the heating power is changed.

Abstract: A fixing device of the present invention includes a first roller that is made of a conductive material, and is rotated and driven; a second roller that is in contact with the first roller in the pressed state; and an induction heating unit that is arranged at the first roller side and concentrates the induction heating to the nip portion of the first roller and change a developer image formed on a fixing medium to a fixed imaged. This induction heating unit of the fixing device is made of a high permeable material, has a core that is open at the surface opposite to the first roller and a coil wound round the core and generates magnetic flux on the core when high frequency current is supplied to the core and has a high projecting portion so that a part of the core closes the first roller.

Abstract: A temperature distribution equalizing structure of a heat roller in an image forming device such as a laser printer which is capable of preventing, in a simple manner, a decrease in the temperature on both ends of a heat roller installed in the laser printer, includes first and second through apertures respectively formed on a pair of bearings disposed on both ends of the heat roller and a gear disposed on one end of the heat roller to thereby allow a halogen lamp to pass therethrough such that the remaining portions of the bearings and the gear are each closed, for preventing a decrease in temperature on both ends of the heat roller and for simultaneously preventing the halogen lamp from being inclined on an interior of the heat roller.

Abstract: An image fixing apparatus for thermally fixing images on an image receiving material at a predetermined image fixing temperature, comprising an image fixing device comprising a core member, and an exothermic phase transition layer provided on said core member, comprising an exothermic phase transition material which is capable of performing reversible phase transition from an amorphous solid state to a crystalline state with liberation of crystallization heat therefrom, and vice versa, and has a melting point higher than said predetermined image fixing temperature, a heating device which maintains the temperature of at least an outer surface of said image fixing device at said predetermined image fixing temperature, a first phase transition device which heats said exothermic phase transition layer, thereby having said exothermic phase transition material perform phase transition from said amorphous state to said crystalline state for liberation of crystallization heat therefrom, a second phase transition devi

Abstract: A toner image heating device for heating a recording material holding a toner image includes: a first heating roller having a plurality of heaters which are different in heat generating region from one another; and a second heating roller having a plurality of heaters which are different in heat generating region from one another. A heat generating region dividing position between said heaters adjacent to each other in said second heating roller is shifted from a heat generating region dividing position between said heaters adjacent to each other in said first heating roller.