Abstract: A power conversion device includes a power supply, transformer comprising a primary winding, a first secondary winding and a second secondary winding, a converter connected to the primary winding, a control circuit connected to the converter, and a startup circuit. The startup circuit comprises a first switching element configured to switch between an ON state and an OFF state, a constant current circuit configured to supply power of a predetermined voltage to the control circuit when the first switching element is in the ON state, and an isolator comprising a first current path connected to a control terminal of the first switching element, and a second current path isolated from the first current path and including a selectable connection to ground. The first switching element is switched to the ON state as a result of current flowing through the first current path when current flows in the second current path.

Abstract: In accordance with an embodiment, a power circuit for supplying electric power to an image forming apparatus equipped with a drive system and a control system comprises a first power supply circuit configured to supply the electric power to the control system; a second power supply circuit configured to supply the electric power to the drive system; a first capacitor configured to smooth the electric power from a commercial power supply and to supply the smoothed electric power to the first power supply circuit; and a second capacitor having a larger capacity than the first capacitor and configured to smooth the electric power from the commercial power supply and to supply the smoothed electric power to the second power supply circuit.

Abstract: A fixing device according to an embodiment of the present invention heats a metal conductive layer of a heat roller using an induction current generating coil. In order to supplement a heat capacity of the heat roller, a press roller having a large heat capacity is heated by a halogen lamp. During a start of activation of an image forming apparatus, when a printer control circuit is started, the supply of electric power to the halogen lamp is started before warming-up is started.

Abstract: In a heat roller of a fixing apparatus according to an embodiment of the present invention, a sleeve is slidable with respect to a supporting roller. Flanges that regulate the sleeve have smooth surfaces, are arranged at gaps apart from a foamed rubber layer of the supporting roller, and freely rotate with respect to the supporting roller. Edges at both ends of the foamed rubber layer of the supporting roller are formed in an R shape and set shorter than the length of a body of the press roller. The sleeve has markings for detecting a state of the heat roller.

Abstract: In a fixing apparatus of an embodiment of the invention, a heat roller forwardly and reversely rotated by a drive motor capable of forwardly and reversely rotating is heated by an induction heating coil also when it is reversely rotated. Further, the roller control temperature of the heat roller by a control system is adjusted according to a time of forward rotation of the heat roller and a time of reverse rotation, or a time when the heat roller and a press roller are separated from each other and a time when they are in contact with each other. Besides, after a specified time has passed since an instruction of reverse rotation or forward rotation by a drive signal, output of the induction heating coil is tuned on.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. At the room temperature, the outer diameter of the elastic roller is smaller than the inner diameter of the metal belt. On the other hand, when the elastic roller is thermally expanded, the metal belt and the elastic roller fit onto each other in a state in which the metal belt fastens the elastic roller.

Abstract: A fixing apparatus according to an embodiment of the present invention controls, using a CPU and a temperature comparator, an inverter circuit that supplies electric power to an induction heating coil and performs temperature control for a heat roller. The CPU adjusts and controls a power value supplied by the inverter circuit. When the adjustment and control of the power value by the CPU is late, the inverter circuit is ON-OFF controlled by the temperature comparator.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. At the room temperature, the outer diameter of the elastic roller is smaller than the inner diameter of the metal belt. On the other hand, when the elastic roller is thermally expanded, the metal belt and the elastic roller fit onto each other in a state in which the metal belt fastens the elastic roller.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. At the room temperature, the outer diameter of the elastic roller is smaller than the inner diameter of the metal belt. On the other hand, when the elastic roller is thermally expanded, the metal belt and the elastic roller fit onto each other in a state in which the metal belt fastens the elastic roller.

Abstract: In a drive detection device for a fixing device according to an embodiment of the present invention, a non-paper passing area of a heat roller is formed by a surface where a metal conductive layer is exposed and a surface where a silicon rubber layer is exposed. The drive detection device has an infrared temperature sensor that detects the temperature of the non-paper passing area. When a detection result of the infrared temperature sensor is fluctuated a fixed amount or more in a predetermined time, the drive detection device determines that the heat roller is rotating. Otherwise, the drive detection device determines that the heat roller is not rotating.

Abstract: A fixing device according to an embodiment of the present invention includes a microcomputer that exclusively performs temperature control for the fixing device. The microcomputer periodically calculates electric power that can be supplied to the fixing device. The microcomputer detects the temperature of the fixing device and the temperature in a printer unit and feedback-controls electric power supplied to the fixing device.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. The width of the metal belt is made larger than that of the elastic roller. Flanges, each of which regulates a sliding movement of the metal belt by being in contact with an edge of the metal belt, are provided on both sides of a press roller opposite the metal belt.

Abstract: An image formation apparatus is provided for supporting adjustment of the distance between a heat roller and a heating unit for heating the heat roller, thereby supporting adjustment of supplied power to the heating unit. The image formation apparatus includes a heat roller for clamping paper with a toner image formed thereon with a pressurization roller; a heating unit being placed facing the heat roller for heating the heat roller; a power supply unit for supplying power to the heating unit; an acquisition unit for acquiring a power value based on the power supplied from the power supply unit; a comparison unit for making a comparison between the power value acquired by the acquisition unit and a predetermined power value; and a display unit for displaying information concerning adjustment of a distance from the heat roller to the heating unit based on the comparison result of the comparison unit.

Abstract: In a drive detection device for a fixing device according to an embodiment of the present invention, a non-paper passing area of a heat roller is formed by a surface where a metal conductive layer is exposed and a surface where a silicon rubber layer is exposed. The drive detection device has an infrared temperature sensor that detects the temperature of the non-paper passing area. When a detection result of the infrared temperature sensor is fluctuated a fixed amount or more in a predetermined time, the drive detection device determines that the heat roller is rotating. Otherwise, the drive detection device determines that the heat roller is not rotating.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. The width of the metal belt is made larger than that of the elastic roller. Flanges, each of which regulates a sliding movement of the metal belt by being in contact with an edge of the metal belt, are provided on both sides of a press roller opposite the metal belt.

Abstract: An image formation apparatus is provided for supporting adjustment of the distance between a heat roller and a heating unit for heating the heat roller, thereby supporting adjustment of supplied power to the heating unit. The image formation apparatus includes a heat roller for clamping paper with a toner image formed thereon with a pressurization roller; a heating unit being placed facing the heat roller for heating the heat roller; a power supply unit for supplying power to the heating unit; an acquisition unit for acquiring a power value based on the power supplied from the power supply unit; a comparison unit for making a comparison between the power value acquired by the acquisition unit and a predetermined power value; and a display unit for displaying information concerning adjustment of a distance from the heat roller to the heating unit based on the comparison result of the comparison unit.

Abstract: A fixing apparatus according to an embodiment of the present invention controls, using a CPU and a temperature comparator, an inverter circuit that supplies electric power to an induction heating coil and performs temperature control for a heat roller. The CPU adjusts and controls a power value supplied by the inverter circuit. When the adjustment and control of the power value by the CPU is late, the inverter circuit is ON-OFF controlled by the temperature comparator.

Abstract: A heat roller of a fixing apparatus according to an embodiment of the invention has a slidable metal belt on an outer side of an elastic roller. At the room temperature, the outer diameter of the elastic roller is smaller than the inner diameter of the metal belt. On the other hand, when the elastic roller is thermally expanded, the metal belt and the elastic roller fit onto each other in a state in which the metal belt fastens the elastic roller.

Abstract: In a heat roller of a fixing apparatus according to an embodiment of the present invention, a sleeve is slidable with respect to a supporting roller. Flanges that regulate the sleeve have smooth surfaces, are arranged at gaps apart from a foamed rubber layer of the supporting roller, and freely rotate with respect to the supporting roller. Edges at both ends of the foamed rubber layer of the supporting roller are formed in an R shape and set shorter than the length of a body of the press roller. The sleeve has markings for detecting a state of the heat roller.

Abstract: A fixing device according to an embodiment of the present invention includes a microcomputer that exclusively performs temperature control for the fixing device. The microcomputer periodically calculates electric power that can be supplied to the fixing device. The microcomputer detects the temperature of the fixing device and the temperature in a printer unit and feedback-controls electric power supplied to the fixing device.