| 摘要 |
PURPOSE:To achieve stable exposure and fixing in a simple constitution, by controlling the power supply upon start of copying to the fluorescent lamp for exposure set by the heater to the temperature corresponding to the maximum quantity of light, according to the temperature of the heat fixing device. CONSTITUTION:When a power source is supplied to a copying machine, current does not flow in a Zener diode ZD1 until the temperature of a heat fixing device H3 reaches the specified temperature, so that a photo transistor TR2 depending on a light emitting diode D3 is not made to conduct. Therefore, a relay RE2 is excited through an amplifier A2 to close a switch RE1C, so that electric power is supplied to fluorescent lamps for exposure FL1, FL2 which are heated by auxiliary heaters H1, H2 to illuminate them. Corresponding to the time of the device H3 reaching the specified temperature, the heaters H1, H2 and the tube walls of the lamps attain such temperature as to maximize the quantity of light of the lamps FL1, FL2. Thereafter, this temperature is maintained by the heaters H1, H2, and by a switch RE2C which is opened or closed depending on the copying operation, excellent copying by stable exposure and stable fixing through the lamps FL1, FL2 may be achieved in a simple constitution. |
