Switching mode power supplying apparatus, fusing apparatus, and image forming apparatus including the same

A fusing apparatus comprising:

• an alternating current (AC) power input unit to receive an AC voltage from an AC power supply source;
• an AC voltage heating element to emit heat according to the AC voltage;
• an AC voltage controller to control a voltage input operation of the AC power input unit and a heat emitting operation of the AC voltage heating element;
• a direct current (DC) power input unit to receive a DC voltage from a DC power supply source;
• a DC voltage heating element to emit heat according to the DC voltage;
• a DC voltage controller to control a heat emitting operation of the DC voltage heating element;
• and
• a heating controller for independently controlling the AC voltage controller and the DC voltage controller by outputting a first driving signal to the AC voltage controller to control an operation of the AC voltage controller and a second driving signal to the DC voltage controller to control an operation of the DC voltage controller,
• wherein, when a DC voltage is input to the DC power input unit, the heating controller blocks an AC voltage input to the AC power input unit by outputting the first driving signal.

A power supply, comprising:

• an AC voltage input terminal;
• a DC voltage input terminal;
• an AC-to-DC conversion circuit to convert a first AC voltage received at the AC voltage input terminal to a first DC voltage to be output from the power supply;
• a DC voltage input detection circuit to detect a second DC voltage received at the DC voltage input terminal;
• and
• a voltage control circuit to disable the AC-to-DC conversion circuit when the DC voltage input detection circuit detects the second DC voltage.

An image-forming apparatus, comprising:

• an image-forming unit to transfer an image to a recording medium;
• an AC voltage input terminal;
• a DC voltage input terminal;
• and
• a power supply, comprising:
• an AC-to-DC conversion circuit to convert a first AC voltage received at the AC voltage input terminal to a first DC voltage to be output from the power supply;
• a DC voltage input detection circuit to detect a second DC voltage received at the DC voltage input terminal;
• and
• a voltage control circuit to disable the AC-to-DC conversion circuit when the DC voltage input detection circuit detects the second DC voltage.

A fusing unit of an image-forming apparatus, comprising:

• an AC voltage heating element to receive an AC voltage from an AC voltage input terminal and to generate heat based on the received AC voltage;
• a DC voltage heating element to receive a DC voltage from a DC voltage input terminal and to generate heat based on the received DC voltage;
• and
• a fusing unit controller to receive the AC voltage and the DC voltage and to output an AC voltage heating element control signal and a DC voltage heating element control signal to control operation of the AC voltage heating element and the DC voltage heating element, respectively,
• wherein the fusing unit controller outputs the AC voltage heating element control signal based on whether the AC voltage detector detects the AC voltage and whether the DC voltage detector detects the DC voltage.