| 摘要 |
PURPOSE:To prevent a diode from being destroyed by an overcurrent in the case of the maintenance and the inspection, etc., of a fixing device by connecting a resistance element to a rectifying element in series. CONSTITUTION:A heating roller 1 has a halogen heater inside and is made of aluminum, and the surface thereof is coated in an insulated state. A spring 2 which contacts by two points is disposed at the end part of the roller 1, and a carbon resistance 3 of about 100kOMEGA and the diode 4 being the rectifying element, whose reverse breakdown strength is about 600V-2kV, are connected to the spring 2 in series, then the anode side of the diode 4 is grounded. A pressure roller 5 having high-resistance conductive sponge on the core bar of a center part is disposed under the roller 1 so that it may press-contact with the roller 1, and a contact 6 is connected to the end part of the core bar of the roller 5. A carbon resistance 7 of about 100kOMEGA and the same diode 8 as the diode 4 are connected to the contact 6 in series and the cathode side of the diode 8 is grounded. Therefore, a current is restricted by the resistance 7, so that the diode is prevented from being destroyed. |
