Abstract: An electrophotographic fixing device allowing a flow of an AC current through an electromagnetic induction coil arranged close to a heating roller having a metal layer formed of a conductor and allowing the heat generation of the heating roller to heat a to-be-fixed member, in which the fixing device comprises a circuit board for outputting the AC current from an output terminal and passing the current through the electromagnetic induction coil, a conductive plate metal having one end side fixed by a fastening screw to the output terminal of the circuit board, a male-side connection terminal provided on the other end of the plate metal, and a female-side connection terminal provided at an end of a leader line of the electromagnetic induction coil and detachably connected to a male-side connection terminal.

Abstract: The present invention provides a fixing device and a digital photocopier which can shorten the time from an instruction of starting image formation to end of fixing. The fixing device is provided in a cylinder made of metal and having a small thickness, and includes a magnetic excitation coil. When the power source is turned on, all the electric power defined by subtracting an electric power amount consumed by components other than the fixing device is supplied to the magnetic excitation coil to perform heating. As the structural components of the photocopier and auxiliary devices added to the photocopier operate, the electric power defined by subtracting, from the maximum input electric power, the electric power consumed by the structural components of the photocopier and the auxiliary devices is supplied to perform heating. In this manner, the heat roller of the fixing device is heated, in a short time, to a temperature which enables fixing, so that the time required for first copying can be shortened.

Abstract: A fixing device comprising an endless heating member which is adapted to be contacted with a fixable member to thereby enable an image on the fixable member to be thermally fixed, an electromagnetic inductive coil member disposed close to the endless heating member and inductively heating the endless heating member, and an AC power supply circuit supplying an AC current to the electromagnetic inductive coil member. The coil member is constructed such that in a state where the coil member is positioned in the fixing device, a ratio between an inductance L of the coil member and a load resistance R of the coil member meets a condition of L/R<50×10−6 (H/&OHgr;).

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: An electrophotographic fixing device allowing a flow of an AC current through an electromagnetic induction coil arranged close to a heating roller having a metal layer formed of a conductor and allowing the heat generation of the heating roller to heat a to-be-fixed members. The fixing device comprises a circuit board for outputting the AC current from an output terminal and passing the current through the electromagnetic induction coil. A connection plate having a thickness twice or more the current penetration depth and having one end side fixed by a fastening screw to the output terminal of the circuit board, and a male-side connection terminal provided on the other end of the plate metal. A female-side connection terminal provided at an end of a leader line of the electromagnetic induction coil is detachably connected to the male-side connection terminal.

Abstract: A fixing device using induction heating includes an endless member having a metal layer of a conductive material; and an electromagnetic induction coil arranged close to said endless member, alternating current being supplied to said coil, thereby generating heat to heat up said endless member, said coil being wound onto a core member arranged in a width direction of said endless member, and an expansion of a folded portion of said coil being absorbed by a narrower portion of said core member, thereby maintaining to be constant the width of a gap between said coil and said endless member.

Abstract: The present invention is a fixing device for use in an electrophotographic apparatus arranged in a structure in which a high-frequency current is flowed through an induction coil provided close to an endless member having a metal layer made of a conductive material and the endless member is caused to generate heat to heat a material to be fixed. This fixing device is characterized in that, when a start-up operation is started by electrically conducting the induction coil, the endless member is rotated after the metal layer reaches a temperature higher than a final setting temperature, and for a predetermined time from starting rotation of the endless member, a high-frequency current having a size corresponding to a control value of a temperature lower than the final setting temperature and higher than a target temperature is supplied to the coil.

Abstract: A fixing device for an electrophotography system, which is capable of efficiently and uniformly heating an object to be heated, which has a coil capable of being easily produced and which is capable of being stably fixing a fixed material, is provided by preventing the distance between the going and returning portions of a certain turn of the coil from being too close to each other, by preventing the diameter of the coil from changing when the coil is wound, by providing a uniform gap between the coil and the inside surface of the heating roller over the whole length, by preventing the fixing performed by the heating roller to be affected by the turning ON/OFF of a power supply, by preventing noises from being generated from the coil ejecting portion, and by devising the procedure for efficiently winding the coil.

Abstract: In a fixing mechanism which heats a fixation member by generating heat in an endless member by using an induction current obtained from a current flowing through an induction coil, the present invention is characterized in that the induction coil is divided into a plurality of coils in a direction vertical to a moving direction of the fixation member and a coil to which power is supplied is switched according to needs.

Abstract: When a voltage abnormality error signal from a drive control section is at a low level, a control section determines a normal state. When the voltage abnormality error signal has arisen to a high level, the control section does not immediately determine an abnormal state and instead measures a time in which the voltage abnormality error signal is at the high level. If the measured time does not exceed a predetermined error timer value (limit value) T, the control section ignores this abnormal state as a temporary voltage abnormality. If the time in which the voltage abnormality error signal is at the high level exceeds the error timer value T, the control section determines a serviceman call error (SC) as the occurrence of voltage abnormality.

Abstract: A fixing device comprising an endless heating member which is adapted to be contacted with a fixable member to thereby enable an image on the fixable member to be thermally fixed, an electromagnetic inductive coil member disposed close to the endless heating member and inductively heating the endless heating member, and an AC power supply circuit supplying an AC current to the electromagnetic inductive coil member. The coil member is constructed such that in a state where the coil member is positioned in the fixing device, a ratio between an inductance L of the coil member and a load resistance R of the coil member meets a condition of L/R<50×10−6 (H/&OHgr;).

Abstract: The present invention provides a fixing device and a digital photocopier which can shorten the time from an instruction of starting image formation to end of fixing. The fixing device is provided in a cylinder made of metal and having a small thickness, and includes a magnetic excitation coil. When the power source is turned on, all the electric power defined by subtracting an electric power amount consumed by components other than the fixing device is supplied to the magnetic excitation coil to perform heating. As the structural components of the photocopier and auxiliary devices added to the photocopier operate, the electric power defined by subtracting, from the maximum input electric power, the electric power consumed by the structural components of the photocopier and the auxiliary devices is supplied to perform heating. In this manner, the heat roller of the fixing device is heated, in a short time, to a temperature which enables fixing, so that the time required for first copying can be shortened.

Abstract: A fixing device is provided, the fixing device using induction heating for causing alternating current to pass through an electromagnetic induction coil, provided inside a heating roller made of a metal, to cause the heating roller to generate heat to heat a member to be fixed, wherein the center of the coil in the axial and longitudinal direction is coincident with the center of a thermal load of the heating roller as a member to be heated.

Abstract: The fixing device fixes toner to a paper by a nip between a heating roller and a press roller which are opposed to each other. An exciting coil is provided inside the heating roller. Temperature detection mechanisms are provided at least two positions on the outer circumferential surface of the heating roller, between the exciting coil and a metal layer of the heating roller, or on the inner circumference of the exciting coil. Two of the temperature detection mechanisms are respectively provided at a center part and an end part in the lengthwise direction of the heating roller, with a predetermined angle inserted therebetween on the circumference of the metal layer of the heating roller. A data table is provided to detect the temperature of a wire material forming the exciting coil, from an extent of a temperature increase while the exciting coil is electrically conducted or an extent of a temperature decrease after the electric conduction to the exciting coil is stopped.

Abstract: The present invention includes individually (independently) a drive control section for driving/controlling an induction heating device of a fixing device and a main-body control section for entirely controlling an electronic copying machine. The start-up processing for the induction heating device is started prior to start-up processing for parts of the main body of the electronic copying machine other than the induction heating device.

Abstract: A fixing device having a heat roller which is adapted to be moved at the same velocity as the transferring speed of a paper with an image thereon and is adapted to be contacted with the paper to thereby enable the image on the paper to be thermally fixed, and an induction heating mechanism for performing an induction heating of the heat roller. The induction heating mechanism having a coil, and a supporter for supporting the coil, and the coil is constituted by a plurality of litz wir which are designed to be altered in the manner of combination or of connection thereof, thereby enabling a plurality of different electric voltages to be applicable.

Abstract: A high-frequency current is supplied from a high-frequency generating circuit to a coil of a heat roller, and a high-frequency magnetic field is generated from the coil. The high-frequency magnetic field causes an eddy current to be generated in the heat roller, and a developer image on a recording medium is fixed by self-generation of heat of the heating roller based on an eddy-current loss. Electric wires between the high-frequency generating circuit and the coil are electrically shielded by a shield member.

Abstract: When a voltage abnormality error signal from a drive control section is at a low level, a control section determines a normal state. When the voltage abnormality error signal has arisen to a high level, the control section does not immediately determine an abnormal state and instead measures a time in which the voltage abnormality error signal is at the high level. If the measured time does not exceed a predetermined error timer value (limit value) T, the control section ignores this abnormal state as a temporary voltage abnormality. If the time in which the voltage abnormality error signal is at the high level exceeds the error timer value T, the control section determines a serviceman call error (SC) as the occurrence of voltage abnormality.

Abstract: A fixing device comprising a heat roller which is adapted to be moved at the same velocity as the transferring speed of a paper with an image thereon and is adapted to be contacted with the paper to thereby enable the image on the paper to be thermally fixed, and an induction heating mechanism for performing an induction heating of the heat roller. The induction heating mechanism comprises a coil, and a supporter for supporting the coil, and the supporter has a frame structure which is partitioned into a plurality of sections which are partitioned in a direction perpendicular to the transferring direction of the paper.

Abstract: Disclosed is a fixing apparatus in which a cylindrical roller having a thin metal layer is heated by an induction heating. In order to shorten the rising time required for elevating the temperature from the stopped state to a predetermined temperature in fixing a toner image transferred onto a paper sheet to the paper sheet, a coil covering member is arranged within the heating roller between an exciting coil and the inner wall of the heating roller, the coil covering member being colored in a color effective for reflecting the infrared ray radiated from the heating roller toward the heating roller. The coil covering member is formed of a material exhibiting electrical insulating properties and heat insulating properties and having a small heat capacity.