Abstract: An induction heating roller apparatus has a heating roller for generating heat with an induction current by being magnetically coupled to an induction coil, and a plurality of induction coils placed in a dispersed state in an axial direction inside the heating roller and also set such that adjacent heating rollers are in mutually reversed winding directions so that generated flux has the same polarity. A high frequency power supply is provided for supplying high frequency power to the plurality of induction coils.

Abstract: An induction heating roller device that keeps leakage current within specifications and prevents the occurrence of erroneous operations caused by common mode noise. The induction heating roller device includes an induction coil, a grounded heating roller magnetically coupled to the induction coil and heated by electro-magnetic induction. A power factor improving capacitor is connected in parallel to and near the induction coil and has a grounded intermediate point. A high-frequency power source biases the induction coil. The leakage current produced by distributed capacitance between the induction coil and the heating roller is returned to the high-frequency power source via the power factor improving capacitor. Thus, the leakage current does not flow out of the induction heating roller device.

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: An induction heating roller, a fixing apparatus and an image forming apparatus are disclosed as including a heating roller (TR) comprised of a hollow roller base body (BB), composed of electrically insulating material, and a plurality of secondary coil components (ws), composed of closed circuits, respectively, which are formed over the roller base body. The heating roller (TR) internally receives an induction coil unit (IC) including a primary coil (wp) which is coupled with the secondary coils in a core-less transformer coupling relationship. The secondary coil components (ws) of the heating roller (TR) have a secondary resistance value (Ra) which is nearly equal to a secondary reactance (Xa), i.e. in case of Ra/Xa=?, a formula is expressed as 0.1<?<10. Further, the primary coil (wp) of the induction coil unit (IC) is comprised of a plurality of coil components which are connected between a wire pair (WP) in parallel to one another.

Abstract: To provide an induction heating roller unit that can efficiently supply power to a heating roller, and fixing device and image forming apparatus incorporating the same. The induction heating roller unit includes: a heating roller; and an induction coil having an outer diameter more than 0.7 times that of the heating roller, the heating roller being concentrically disposed outside said induction coil and generating heat by the effect of an induced current caused by a magnetic field produced by the induction coil. Since the ratio of the outer diameter of the induction coil to that of the heating roller is 0.7 or higher, power can be transferred from the induction coil to the heating roller with an extremely high efficiency.

Abstract: An induction heating roller device that keeps leakage current within specifications and prevents the occurrence of erroneous operations caused by common mode noise. The induction heating roller device includes an induction coil, a grounded heating roller magnetically coupled to the induction coil and heated by electro-magnetic induction. A power factor improving capacitor is connected in parallel to and near the induction coil and has a grounded intermediate point. A high-frequency power source biases the induction coil. The leakage current produced by distributed capacitance between the induction coil and the heating roller is returned to the high-frequency power source via the power factor improving capacitor. Thus, the leakage current does not flow out of the induction heating roller device.

Abstract: An induction heating roller device that reduces noise emission to the outside and facilitates insulating between induction coils and nearby metal materials. The induction heating roller device includes a heating roller, a plurality of induction coils arranged in the axial direction of the heating roller, and a high-frequency power source for supplying high-frequency power to the plurality of induction coils. The high-frequency power source has a first output terminal set at a stable potential, and a second output terminal set at a non-stable potential. A pair of induction coils are arranged at the ends of the heating roller and a first end of the coils is positioned at the end of the heating roller and a second end of the coils is positioned in the central side of the heating roller. The first end of each of the two induction coils is connected to the first output terminal, and the second end of each of the two induction coils is connected to the second output terminal.

Abstract: An electrodeless discharge lamp system includes an excitation coil placed in proximity of the electrodeless discharge lamp, a resonance circuit for supplying appropriate power to the excitation coil, and a high frequency power source driver and wherein, the combined output is achieved by operating the parallel connected power sources in synchronization or approximately in synchronization with each other.

Abstract: To provide an induction heating roller unit that can efficiently supply power to a heating roller, and fixing device and image forming apparatus incorporating the same. The induction heating roller unit includes: a heating roller; and an induction coil having an outer diameter more than 0.7 times that of the heating roller, the heating roller being concentrically disposed outside said induction coil and generating heat by the effect of an induced current caused by a magnetic field produced by the induction coil. Since the ratio of the outer diameter of the induction coil to that of the heating roller is 0.7 or higher, power can be transferred from the induction coil to the heating roller with an extremely high efficiency.

Abstract: An induction heating roller apparatus has a heating roller HR 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 IC1, IC3 placed to be opposed to a plurality of heating areas of the heating roller HR, second induction coils IC2 placed opposite a part astride adjacent heating areas of the heating roller HR, a high frequency power supply HFS for supplying high frequency power to the first and second induction coils IC1, IC3 and IC2, and induction coil selection means F1, F2 and F3 for selectively supplying high frequency output to the first induction coils IC1, IC3 opposed to the heating areas of the heating roller according to the size of the object to be heated and the second induction coils IC2 placed astride the heating areas of the heating roller HR.

Abstract: To provide an induction heating roller apparatus and an image formation apparatus capable of evenly heating a heating roller in an axial direction, easily performing insulation among a plurality of induction coils placed in a dispersed state and rendering a heating area of the heating roller switchable if desired.

Abstract: An induction heating roller apparatus that varies temperature distribution in the axial direction of a heating roller. The apparatus includes a heating roller and a plurality of induction coils arranged separately along an axial direction of the heating roller. The heating roller includes a secondary coil that is air-core transfer coupled to the induction coils. The apparatus further includes a plurality of capacitors, each being connected to one of the induction coils to form a resonance circuit. At least one of the resonance circuits has a resonance point that differs from the remaining resonance circuits.

Abstract: An induction heating roller apparatus that varies temperature distribution in the axial direction of a heating roller. The apparatus includes a heating roller and a plurality of induction coils arranged separately along an axial direction of the heating roller. The heating roller includes a secondary coil that is air-core transfer coupled to the induction coils. The apparatus further includes a plurality of capacitors, each being connected to one of the induction coils to form a resonance circuit. At least one of the resonance circuits has a resonance point that differs from the remaining resonance circuits.

Abstract: An induction heating roller, a fixing apparatus and an image forming apparatus are disclosed as including a heating roller (TR) comprised of a hollow roller base body (BB), composed of electrically insulating material, and a plurality of secondary coil components (ws), composed of closed circuits, respectively, which are formed over the roller base body. The heating roller (TR) internally receives an induction coil unit (IC) including a primary coil (wp) which is coupled with the secondary coils in a core-less transformer coupling relationship. The secondary coil components (ws) of the heating roller (TR) have a secondary resistance value (Ra) which is nearly equal to a secondary reactance (Xa), i.e. in case of Ra/Xa=&agr;, a formula is expressed as 0.1<&agr;<10. Further, the primary coil (wp) of the induction coil unit (IC) is comprised of a plurality of coil components which are connected between a wire pair (WP) in parallel to one another.

Abstract: An electrodeless discharge lamp system includes an excitation coil placed in proximity of the electrodeless discharge lamp, a resonance circuit for supplying appropriate power to the excitation coil, and a high frequency power source driver and wherein, the combined output is achieved by operating the parallel connected power sources in synchronization or approximately in synchronization with each other.

Abstract: An electrodeless discharge lamp unit includes an electrodeless discharge lamp that has a luminescent tube with an excitation coil wound round and an auxiliary tube, a high-tension applying circuit to apply pulse voltage of a peak value that is able to dielectric break the discharge space in the luminescent tube and a current injection circuit to apply voltage, that is able to maintain non-ring shaped discharge formed in the luminescent tube by applying pulse voltage by a high-tension applying circuit even when the application of pulse voltage is suspended, to the end of the auxiliary tube.

Abstract: A non-electrode discharge lamp apparatus comprises a discharge tube, exciting coils wound on an outer periphery of the discharge tube, a vessel, having liquid-tightness, containing the discharge tube and the exciting coil means, and lead line guiding means for guiding lead lines connected to the exciting coils to the outside of the vessel, thereby supplying high frequency electric power to the exciting coils through the lead lines. Liquid is prevented from directly contacting the discharge tube and the exciting coils, temperature of the discharge tube can be suitably maintained, and an irradiation efficiency of ultraviolet rays can be prevented from being reduced.

Abstract: This invention suppresses the occurrence of interference in a very short period to prevent device destruction. An inverter circuit of this invention includes a crystal oscillator, which oscillates at a fixed frequency, a load-status detector, which receives a voltage and current to be applied to a load including an inductive or capacitive component and detects the status of the load, a voltage-controlled oscillator, which oscillates at a frequency corresponding to the load status detected by the load-status detector, and a switch, which selects the output of the crystal oscillator or the output of the voltage-controlled oscillator and supplies the selected output to the load. An electrodeless discharge lamp lighting device according to this invention uses an inverter circuit having the above structure.