Patent attributes
A fixing device usable with an image forming apparatus having a fixing roller to fix a toner on a recording medium, a heater to heat the fixing roller, and an alternating current (AC) power source to supply an AC electric power to the heater may include a power converting part to convert the AC electric power of the AC power source and to supply the converted power to the heater; a relay including a first relay contact point disposed on a first AC power supply line between the AC power source and the power converting part and a relay coil to open and close the first relay contact point, the relay selectively supplying the AC electric power from the AC power source to the heater and the power converting part; a direct current (DC) power supplier to supply a DC power to the relay coil; and a thermoswitch interposed between the relay coil and the DC power supplier and mounted adjacent to the fixing roller so as to interrupt the DC power from the DC power supplier to the relay coil, when a temperature of the fixing roller exceeds a threshold temperature, causing the relay coil to open the first relay contact point.
