| 摘要 |
PURPOSE:To prevent electrical accidents and the damage of connecting instruments, by providing a switch which turns on and off a power source in accordance with a fixing device which fixes an apparatus, which consumes a high electric power, in a copying machine and cutting off the power supply automatically when the apparatus is removed. CONSTITUTION:In the state where a lever 12 is turned up to press a pressure roll 3 to a heat roll 1, a magnet 15 approaches a magnet reed switch 16, and the switch 15 is set to the operation state; and if the temperature of the roll 1 is lower than a set value, an AND circuit is operated, and its output is sent to a solid-state relay, and the relay contact is closed to supply electric power to a heater 2, and the roll 1 is heated, and thus, fixation is possible. When the temperature of the roll 1 exceeds the set value, and AND circuit is made unoperated, and the relay contact is opened, and the power supply to the roll 1 is stopped automatically. When the lever 12 is turned down to separate the roll 3 from the roll 1, the switch 16 is made unoperated, and the power supply to the roll 1 is stopped automatically; and in this state, even if a connector in a power supply circuit of the heater 2 is attached or detached, the damage is prevented because of no current. |
