Abstract: A power control method and apparatus to heat a heating roller includes heating a heating roller provided to fix a toner image of print data in an image forming apparatus, the heating roller having a heating resistor to receive roller power. The power control method includes gradually increasing a maximum level of a source power supplied from an external source up to a specific maximum supply level, and supplying the maximum source power to the heating resistor as the roller power while gradually increasing the maximum level of the source power up to a specific maximum supply level, measuring a surface temperature of the heating roller, and supplying the source power of which maximum level is equal to the maximum supply level to the heating resistor as the roller power until the measured surface temperature reaches a specific fixing target temperature, and fixing the toner image onto a printing medium.

Abstract: An image forming apparatus is provided with: a heating unit which generates heat to fuse a toner on a printing medium; a switch which selectively supplies alternating current (AC) power to the heating unit; a first switching driver which drives the switch to supply the AC power to the heating unit; and a first supply limiter which allows the AC power to be supplied to the heating unit by the first switching driver if a polarity of the AC power is the same as a preset polarity, and cuts off the AC power supplied to the heating unit if the polarity of the AC power is opposite to the preset polarity.

Abstract: Provided is an image forming apparatus and a method of controlling the same. When an external power is supplied to a heating resistance member of a fusing unit in the image forming apparatus that is in a standby mode, a power supply unit supplies an internal power to a different load (for example, an exposure unit, a developing unit, or a transfer unit) in one or more time sections so as to supply the internal power to the load at a continuously changing operating frequency.

Abstract: A power control method and apparatus to heat a heating roller. The power control method includes heating a heating roller provided to fix a toner image of print data in an image forming apparatus, the heating roller having a heating resistor to receive roller power, the power control method includes gradually increasing a maximum level of a source power supplied from an external source up to a specific maximum supply level, and supplying the maximum source power to the heating resistor as the roller power while gradually increasing the maximum level of the source power up to a specific maximum supply level, measuring a surface temperature of the heating roller, and further supplying the source power of which maximum level is equal to the maximum supply level to the heating resistor as the roller power until the measured surface temperature reaches a specific fixing target temperature, and fixing the toner image onto a fed printing medium.

Abstract: A power control method includes heating a heating roller provided to fix a toner image of print data in an image forming apparatus, the heating roller having a heating resistor to receive roller power. The power control method includes gradually increasing a maximum level of a source power supplied from an external source up to a specific maximum supply level, supplying the maximum source power to the heating resistor as the roller power while gradually increasing the maximum level of the source power up to a specific maximum supply level, measuring a surface temperature of the heating roller, further supplying the source power of which maximum level is equal to the maximum supply level to the heating resistor as the roller power until the measured surface temperature reaches a specific fixing target temperature, and fixing the toner image onto a fed printing medium.

Abstract: Provided is an image forming apparatus and a method of controlling the same. When an external power is supplied to a heating resistance member of a fusing unit in the image forming apparatus that is in a standby mode, a power supply unit supplies an internal power to a different load (for example, an exposure unit, a developing unit, or a transfer unit) in one or more time sections so as to supply the internal power to the load at a continuously changing operating frequency.

Abstract: An image forming apparatus is provided with: a heating unit which generates heat to fuse a toner on a printing medium; a switch which selectively supplies alternating current (AC) power to the heating unit; a first switching driver which drives the switch to supply the AC power to the heating unit; and a first supply limiter which allows the AC power to be supplied to the heating unit by the first switching driver if a polarity of the AC power is the same as a preset polarity, and cuts off the AC power supplied to the heating unit if the polarity of the AC power is opposite to the preset polarity.

Abstract: A method of controlling a phase of an alternating current (AC) power having an AC voltage waveform having a predetermined cycle includes counting a number of times a zero crossing signal has been generated, the zero crossing signal being generated whenever a level of the AC voltage waveform becomes “0”; calculating a half cycle of the AC voltage waveform based on times at which the counted number of times the zero crossing signal has been generated changes; detecting phases that divide an area surrounded by a waveform corresponding to the half cycle of the AC voltage waveform into a predetermined number of equal areas; and generating control pulse signals based on the detected phases

Abstract: An image fixing control system and method are provided comprising a power supply, a power switching unit, a heating roller, in which a temperature detector detects a temperature of the heating roller, and a controller detects a temperature variation slope of the heating roller using the temperature detected by the temperature detector and controls an on and off switching operation of the power switching unit according to the detected temperature variation slope. Accordingly, by varying a duty ratio of power through a phase control using a temperature variation slope of a heating roller, a fine control of a fixing system can be performed. In addition, since a temperature variation, that is, overshoot or undershoot, of the heating roller is reduced, a fixing efficiency can be increased.

Abstract: A power control method and apparatus to heat a heating roller. The power control method includes heating a heating roller provided to fix a toner image of print data in an image forming apparatus, the heating roller having a heating resistor to receive roller power, the power control method includes gradually increasing a maximum level of a source power supplied from an external source up to a specific maximum supply level, and supplying the maximum source power to the heating resistor as the roller power while gradually increasing the maximum level of the source power up to a specific maximum supply level, measuring a surface temperature of the heating roller, and further supplying the source power of which maximum level is equal to the maximum supply level to the heating resistor as the roller power until the measured surface temperature reaches a specific fixing target temperature, and fixing the toner image onto a fed printing medium.