Abstract: A coated member includes a substrate and a coating layer over the substrate where the coating layer includes at least one of ferromagnetic and magnetic particles dispersed in a binder. The member, which is suitable for use in an electrostatographic printing process, can be in the form of a fuser member, a fixing member, a pressure roller, or a release agent donor member.

Abstract: In an image forming apparatus according to the present invention, a shield plate 202 which is made of a specific material and has a specific thickness is provided between an exciting coil and at least one of a first and a second magnetic field intensity measuring point P1, P2, which prevents a magnetic field of a specific magnetic field intensity or higher from leaking to the outside of the image forming apparatus or alleviates the effect of the magnetic field on the circuits in the apparatus or optionally installed devices.

Abstract: An electrophotography fixing device has a heating roller and an induction heating device. In order to improve heat resistance, heat radiating performance and insulation performance and in order to appropriately uniformly heat the heating roller, in the induction heating device, induction heating coils wound onto a core are fixed by varnish mixed with mica, and the outside surfaces thereof are fixed by a heat resistant bundling band or a molded body of a heat resistant material, or coated with a heat resistant, insulating and thermal conductive sheet. Alternatively, the same sheets as the above described sheet are provided between the core and the coils and between the layers of the coils. In addition, the core is formed with a hole extending in axial directions or holes extending in directions perpendicular to the axial directions. Moreover, the coils are doubly insulated.

Abstract: A heating apparatus for heating a material to be heated by heat generated by induction heat generation member includes a magnetic flux generator, a holder for holding and fixing the magnetic flux generator, and an induction heating member which generates heat by electromagnetic induction heating by an action of magnetic flux generated by the magnetic flux generator. A magnetic flux adjuster adjusts an area in which magnetic flux acts on the magnetic flux generator in a longitudinal direction, of the induction heat generation member, perpendicular to a conveyance direction of a material to be heated. The magnetic flux adjuster includes a magnetic flux adjusting member capable of coming into surface contact with the holder in the longitudinal direction of the induction heat generation member and a moving element for moving the magnetic flux adjusting member by sliding the magnetic flux adjusting member on the surface of the holder.

Abstract: A heating apparatus of an electromagnetic inductive heat generating type has a coil for generating a magnetic flux, a roller member for generating heat by the magnetic flux from the coil, and heating a material to be heated, and a magnetic flux shield member for shielding the magnetic flux from the coil to the roller member to thereby vary the generated heat distribution of the roller member, wherein provision is made for a guide provided in non-contact with the roller member for guiding the movement of the magnetic flux shield member to a predetermined magnetic flux suppressing position, thereby realizing an improvement in the faulty operation of the magnetic flux shield member.

Abstract: An image forming apparatus capable of realizing low power consumption of a fixing means is provided. The image forming apparatus includes an image forming means for forming an unfixed image t on a recording material P, and a fixing means 10 for heat-fixing the unfixed image. In the image forming apparatus, the fixing means 10 is of electromagnetic induction heating type wherein the fixing means 10 includes a magnetic flux generation means 36 and an induction heating member 10a for generating heat through electromagnetic induction by the action of generated magnetic flux of the magnetic flux generation means, and the unfixed image is heat-fixed on the recording material by generated heat of the induction heating member 10a.

Abstract: A fixing apparatus an aspect of the present invention includes, a heating object which generates the heat by a magnetic flux produced from a coil which generates a predetermined magnetic flux by electromagnetic induction in accordance with a frequency of an input current, and a pressurization mechanism which can provide a predetermined pressure to the heating object, and a coil of the heating object is formed of a litz wire obtained by twisting the number of conductors having a small cross section which are not affected by the skin effect caused due to the frequency of the input current, the number of which allows passage of a quantity of current to be inputted.

Abstract: An inductor core 10 is proposed for a heatable godet roll comprising a plurality of inductor core laminations 11 arranged radially in a star shape with radial sections 12 and respectively one outer axial section 13 and an inner axial section. The inductor core 10 has end plates 19, 20 with respectively one surface 21 complementary to the radial sections 12 and fixing means, wherein the inductor core laminations 11 are arranged between the end plates 19, 20 and wherein the fixing means 22 are set up to fix the inductor core laminations 11 at their radiation sections 12 on the end plates 19, 20 or alternatively and/or on the outer surface of an inner tube.

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: The present invention provides an induction heating apparatus including a fixing belt that heats an unfixed image on recording paper, an excitation coil that induction-heats the fixing belt, an inverter circuit that supplies power to the excitation coil, a harness that electrically connects the excitation coil and the inverter circuit. The harness is constructed of a litz wire having a resistance of the harness section of 0.016 ? or below formed by stranding several tens of wires which are conductive wires coated with an insulator into a predetermined thickness.

Abstract: A fusing device of an image forming apparatus and method thereof are provided. The fusing device and method include a conductive member having a linear portion for contacting a printing medium, a fusing film for sliding on a circumference of the conductive member, a pressing roller for contacting the fusing film in the linear portion, forming a fusing nip area, and rotating the fusing film, and an induction heating unit for heating the conductive member by induction and generating heat. The thickness of the conductive member in the fusing nip area is smaller than the thickness of the conductive member in other areas.

Abstract: An induction heating type of fixing device to fix a recording material having a toner image thereon, having a heating member, an induction coil divided into a plurality of parts, a temperature detector for detecting a temperature of the heating member, a signal generator for generating a switching signal that periodically controls permission and prohibition of energization of each of the divided induction coils, and a controller for controlling supply of a driving current to each of the divided induction coils to heat the heating member. The controller controls the energization by periodically switching the driving current to each of the divided induction coils on the basis of an energization signal that determines the permission and the inhibition of the driving currents according to a signal of temperature detected by the temperature detector, and the switching signal.

Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.

Abstract: A heating apparatus of an electromagnetic induction heating type includes a coil and a roller which generates heat by the action of magnetic flux generated from the coil. A recording material is heated by the roller. The heating apparatus further includes a movable magnetic flux decreasing member for decreasing magnetic flux, generated from the coil, acting on the roller. In the heating apparatus, a shutter is moved toward an effective position at which a temperature in a non-conveyance area is lowered when a recording material having a size lower than a maximum conveyable size is conveyed, and is moved away from the effective position depending on the temperature in the non-conveyance area, irrespective of the size of the recording material to be conveyed.

Abstract: A heat apparatus for an electromagnetic induction heating system comprises a heat roller that comprises magnetic and conductive material. The heating apparatus also comprises a magnetic excitation coil that is positioned around a portion of the periphery of the heat roller. The magnetic excitation coil is configured to generate a magnetic field that extends to the heat roller, to generate an eddy current within the heat roller, and to generate Joule heat within the heat roller. The magnetic excitation coil is configured to generate a smaller magnetic field at the center area of the heat roller than at the side areas of the heat roller.

Abstract: A heating roller (21) includes a heat generating layer (22) that generates heat by electromagnetic induction, a heat insulating layer (23), and a supporting layer (24), which are provided inwardly in this order. The supporting layer (24) is formed of a material having a specific resistance of 1×10?5 ?m or higher. Therefore, even when the heat generating layer (22) has a thickness smaller than a skin depth, i.e. a thickness defined by a flow of an induction current, so that magnetic flux penetrates the heat generating layer (22) and even reaches the supporting layer (24), heat generation of the supporting layer (24) under an eddy current can be suppressed. Thus, the heat generating layer (22) can be decreased in thermal capacity, and heat generation of the supporting layer (24) is suppressed, so that only the heat generating layer (22) can be heated efficiently. As a result, a warm-up time can be reduced. Further, breakage by heat of, for example, bearings supporting the heating roller (21) can be prevented.

Abstract: In an electromagnetic induction heating-type heating apparatus for moving a temperature decreasing member toward or apart from an effective position where a temperature in a predetermined area is decreased in order to take countermeasure against temperature rise at a non-sheet passing portion of a heating roller, a Curie temperature of the heating roller is not less than a predetermined image heating temperature and is less than a heat-resistant temperature of the heating apparatus.

Abstract: A distance defined by expression 2 is secured between the exciting coil and the protection cover. This not only prevents a magnetic field with a specific magnetic field intensity or higher from leaking to the outside but also reduces the effect on the circuits in the apparatus or optionally installed circuits (including a printer controller and a FAX controller).

Abstract: A heating apparatus includes a magnetic field generator that generates an alternating magnetic field, a rotatable member disposed in the alternating magnetic field and capable of generating heat by electromagnetic induction, a temperature detector that detects a temperature of the rotatable member, a comparator that compares the detected temperature to a target temperature: and a controller that controls electric energy supply to the magnetic field generator based on detected temperatures of different positions of the rotatable member.

Abstract: A fixing device has a magnetic field generator; an electric power supplier for electric power supply to the magnetic field generator; electric power controller for controlling an electric power value to be supplied by the electric power supplier; a fixing member, disposed in the magnetic field, having an electroconductive layer which generates heat by eddy current generated by the magnetic field; a temperature detecting member for detecting a temperature of the fixing member; a discriminator for discriminating whether the apparatus is in order by comparing a detected temperature to a reference temperature in a period from a start of heating the fixing member to arrival at a predetermined temperature; and a reference temperature changer for changing the reference temperature on the basis of the supplied electric power value upon the electric power controller changing the electric power value.

Abstract: In a fixing device according to this invention, a coil bobbin around which coils are formed into a predetermined shape is formed at an induction heating portion including a plurality of coils. To minimize the axial temperature difference of a heating roller, the coil bobbin has a shape with which the interval between coils is held at a predetermined interval.

Abstract: In a fixing device according to this invention, coils are formed on a coil bobbin having a predetermined shape at an induction heating portion including a plurality of coils. In order to minimize the temperature difference of a heating roller in the axial direction, the coil bobbin has a shape for holding the interval between the coils at a predetermined interval.

Abstract: An excitation coil and/or a core member, which has a characteristic frequency other than frequencies used, is employed. Thereby, resonance is prevented between adjacent coils or between a coil and an adjacent component such as a core member.

Abstract: Information on a temperature of a heat generation member at a position which is in the neighborhood of an end portion of a conveyance area of a material, to be heated, having a maximum size and in the neighborhood of a non-conveyance area of a material, to be heated, having a size smaller than the maximum size is detected by temperature information detector, and a changer lowers a target temperature of the heat generation member depending on a detection result of the temperature information detector. Thereafter, when the detection result of the temperature information detector reaches a predetermined temperature, a magnetic flux adjusting member is started to be moved by a moving device.

Abstract: A heating apparatus of an electromagnetic inductive heat generating type using a magnetic flux shield member, the heating apparatus including a coil for generating a magnetic flux, a roller member for generating heat by the magnetic flux from the coil, and heating a material to be heated, the magnetic flux shield member for shielding the magnetic flux from the coil to the roller member to thereby vary the generated heat distribution of the roller member, and a guide member provided in non-contact with the roller member for guiding the movement of the magnetic flux shield member to a predetermined magnetic flux suppressing position, thereby realizing an improvement in the faulty operation of the magnetic flux shield member.

Abstract: A CPU detects a temperature of a central part of a heating roller. If the detected temperature does not exceed 180° C., the CPU drives a central coil or a side-end coil for 0.4 second in accordance with a temperature difference between the central part of the heating roller and a side-end part of the heating roller. Then, the CPU drives the side-end coil or central coil for 0.2 second. Thereafter, the CPU detects the temperature of the central part and repeats the driving control until the detected temperature reaches 180° C.

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: A heating apparatus includes a core; magnetic flux generating means having an excitation coil provided outside the core; an induction heat 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, the heating portion being elongated in a longitudinal direction crossing with a direction in which the recording material is fed to the heating portion; magnetic flux adjusting means for changing a distribution, in the longitudinal direction, of densities of the magnetic flux generated by the magnetic flux generating means in the heating portion; the magnetic flux adjusting means including a magnetic flux shield member, and moving means for moving the magnetic flux shield member to a position for adjusting the magnetic flux generated by the magnetic flux generating means, the magnetic

Abstract: A fixing device includes a coil for generating a magnetic field; a heating medium having an electroconductive layer which is provided at its inside with said coil, wherein eddy currents are generated by a magnetic field generated by current through said coil so that heat is generated in said electroconductive layer, and an unfixed toner image is fixed on a recording material by the heat, and said heating medium has an inner side spaced from said coil and having a dark color.

Abstract: A fixing device includes a heating roller, electromagnetic induction heater for heating the heating roller, and a pressurization roller disposed in contact with the outer periphery of the heating roller. The electromagnetic induction heater has a support extending like a tube along the outer periphery of the heating roller containing both ends in an axial direction orthogonal to a rotational direction of the heating roller and both sides parallel with the axial direction outside the heating roller. A coil is wound around the outer face of the support so as to contain a center axis of the heating roller inside the tubular part. The fixing device nips and transports recording paper to which toner has been transferred in a press contact nip part between the heating roller and the pressurization roller so as to fix an image.

Abstract: An image heating device is operational to estimate a temperature of a pressure roller so as to determine a set temperature for a roller belt in a subsequent image heating period.

Abstract: A heating apparatus has a magnetic flux generator and a rotatable induction heating element for generating heat through electromagnetic induction by the action of magnetic flux generated by the magnetic flux generator, and heats a material to be heated by causing the material to be heated to contact the induction heating element. The heating apparatus further includes a thermistor for detecting a surface temperature of the induction heating element, power supply circuits for controlling power to be supplied to the magnetic flux generator on the basis of signals from the temperature detection, a Curie temperature reaching detector for detecting that the temperature of the induction heating element reaches the Curie temperature, and control circuits for detecting that the material to be heated is wound around the induction heating element on the basis of signals from the thermistor and the Curie temperature reaching detector.

Abstract: An induction heating device for inductively heating an object to be heated which is formed of conductive material has a holder. The device also has a coil for inductively heating the object. The coil is supported by the holder. The coil is composed of a plurality of turns of conductor forming a layer, which is positioned along the object. Between conductor sections of the coil through which electric currents respectively flow in the same direction is formed a gap through which temperature of the object is detected. The device is capable of accurately detecting the temperature of heating region of the object, at low cost, and capable of increasing stability and safety in control of the temperature.

Abstract: The present invention relates to a device including a body to be heated to which a magnetic field is supplied to generate heat and which heats a developer on a material to be recorded, a plurality of coil bodies which generate an induced heat in the body to be heated from the outside of the body to be heated and which include litz wires having cross sections formed in rectangular shapes and which are disposed in a longitudinal direction of the body to be heated, and a pressure applying member which contacts the body to be heated in a predetermined position and which fixes the developer on the material to be recorded passing between the pressure applying member and the body to be heated.

Abstract: A fixing device has a magnetic field generator; an electric power supplier for electric power supply to the magnetic field generator; electric power controller for controlling an electric power value to be supplied by the electric power supplier; a fixing member, disposed in the magnetic field, having an electroconductive layer which generates heat by eddy current generated by the magnetic field; a temperature detecting member for detecting a temperature of the fixing member; a discriminator for discriminating whether the apparatus is in order by comparing a detected temperature to a reference temperature in a period from a start of heating the fixing member to arrival at a predetermined temperature; and a reference temperature changer for changing the reference temperature on the basis of the supplied electric power value upon the electric power controller changing the electric power value.

Abstract: The image heating apparatus includes a heating member, a first coil unit having a first holder in which a first excitation coil is sealed, the first excitation coil being provided for generating a magnetic field to induce an eddy current in the heating member, and a second coil unit having a second holder in which a second excitation coil is sealed, the second excitation coil being provided for generating a magnetic field to induce an eddy current in the heating member. The image heating apparatus having such structure enables easy assembly work while being capable of conducting nonuniform heating.

Abstract: The image heating apparatus includes a heating member, a first coil unit having a first holder in which a first excitation coil is sealed, the first excitation,coil being provided for generating a magnetic field to induce an eddy current in the heating member, and a second coil unit having a second holder in which a second excitation coil is sealed, the second excitation coil being provided for generating a magnetic field to induce an eddy current in the heating member. The image heating apparatus having such structure enables easy assembly work while being capable of conducting nonuniform heating.

Abstract: A heating apparatus, for heating a material P to be heated by heat from a heat generation member which has a predetermined curie temperature characteristic and generates heat by magnetic flux produced by a magnetic flux generation device. The apparatus includes a discrimination device for discriminating whether or not the curie temperature characteristic of the heat generation member is a predetermined characteristic and a control device for terminating the supply of electric power to the magnetic flux generation device when the discrimination device determines that the curie temperature characteristic is not the predetermined characteristic.

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 fixing apparatus has an excitation coil disposed adjacent the heating element; a voltage source for applying to the excitation coil a high frequency electric power provided by modulating an input AC electric power with a high frequency, wherein the heating element is heated by induction by the excitation coil supplied with the high frequency electric power, wherein the heating element has a characteristic frequency which is unequal to integer multiple s of a frequency of the AC electric power.

Abstract: An induction heating device or work coil for heating electroconductive material to a desired temperature that can be used on a roll or cylinder of any diameter. The work coil has an open core of ferrite material shaped in a U. Wire is wound around the opposing legs of the U so that on excitation one leg becomes the N pole and the other leg becomes the S pole and the polarity alternates as the polarity of the excitation current alternates. A substantially thin rectangular flat layer of ferrite can be attached to ends of each pole piece. Each layer of ferrite has having a length sufficient to cover bottom end of each leg and a width in the direction of an axis perpendicular to the face of the U that corresponds to the width of the desired control heating effect.

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: An apparatus and method of controlling the driving of a heat source using an AC voltage. If the temperature of the heat source is lower than a reference temperature and the level of the AC voltage is greater than a reference level, the level of a sensing signal is changed. Then, it is determined whether a predetermined period of time has lapsed from the moment when the level of the sensing signal has been changed. Thereafter, if it is determined that the predetermined period of time has lapsed from the moment when the level of the sensing signal has been changed, the heat source is driven when the level of the AC voltage is a zero level.

Abstract: A heating apparatus includes a heat generation member for generating heat using magnetic flux; a coil for generating the magnetic flux by electric power supply thereto, the coil being disposed in the heat generation member, wherein a material to be heated is fed and introduced in a heating portion of the heat generation member to heat an image on the material to be heated by heat generated by the heat generation member: a movable member which is movable in the heat generation member; a rotatable drive transmission member for transmitting a driving force to the movable member, wherein the drive transmission member has a hollow rotation shaft, and a supply line for supplying the electric power is connected to the coil through the hollow rotation shaft.

Abstract: A heating roller (21) includes a heat generating layer (22) that generates heat by electromagnetic induction, a heat insulating layer (23), and a supporting layer (24), which are provided inwardly in this order. The heat generating layer (22) is composed of at least two layers that are a first heat generating layer of a magnetic material and a second heat generating layer of a non-magnetic material. The first heat generating layer has a specific resistance higher than a specific resistance of the second heat generating layer and a thickness larger than a thickness of the second heat generating layer. This allows the second heat generating layer to function effectively as a heat generating part that generates heat by electromagnetic induction. Thus, compared with the case where the heat generating layer (22) is formed only of a single layer of a magnetic material, heat generation efficiency is increased, thereby allowing warm-up time to be reduced.

Abstract: An induction heating device for inductively heating an object to be heated which is formed of conductive material has a holder. The holder is positioned outside the object. The device has an exciting coil for inductively heating the object. The exciting coil is supported by the holder. The exciting coil is composed of a plurality of turns of conductor forming a layer, which is positioned along the object. The device also has a demagnetizing coil which is positioned along the layer of the exciting coil. In the demagnetizing coil, a back electromotive force is induced in accordance with a magnetic field produced by the exciting coil, so as to cancel the magnetic field. Stability in the temperature control for the object such as a heating roller can be improved by effective function of the demagnetizing coil. The device can be miniaturized and configured at low cost.

Abstract: According to a mode of the present invention, there is disclosed a fixing apparatus comprising a non-contact temperature detection section which detects a temperature by infrared rays radiated from a heating member, to made uniform a surface temperature of the heating member in an axial direction and a rotation direction based on first temperature information for detecting a temperature difference of the axial direction of the heating member and second temperature information for detecting the temperature difference of the rotation direction of the heating member.

Abstract: An induction-heating fixing apparatus comprising: a heating member for fixing a toner image to a recording material carrying the toner image by heating the toner image; an induction-heating coil divided into a plurality of coils and comprising a first induction-heating coil and a second induction-heating coil adjacent to each other; and a power-distribution control member for controlling power distribution by supplying a driving-current to the plurality of induction-heating coils in order to heat the heating member, wherein the power-distribution control member comprises a determining section for selecting whether to supply the driving-current to the first induction-heating coil or the second induction-heating coil.

Abstract: An image heating apparatus according to the present invention includes a fixing sleeve, a guide member that is arranged in an inner circumferential section of fixing sleeve and rotatably holds the fixing sleeve, a pressure roller that press-contacts with the guide member through the fixing sleeve and forms a fixing nip, and heating unit that heating the fixing sleeve and heats paper conveyed in the fixing nip with the rotation of the fixing sleeve. Grease that increases slide property is applied to an interface between the fixing sleeve and guide member, and the surface roughness of at least an area of an inside surface of the fixing sleeve contacting with the above-described guide member is made to be 0.05 or more in an Rz value.

Abstract: A thermal processing roller includes a heat transfer medium flowing path therein and heats a member to be processed abutting against a surface of the roller or absorbs heat therefrom by heat transfer fluid flowing through the heat transfer medium flowing path, wherein a sealed chamber extending in a longitudinal direction of the roller and in which heat transfer medium of vapor-liquid two phases is sealed is formed within a thick portion of the roller.