Heating unit, auxiliary power unit, fixing unit, and image forming apparatus

A fixing unit comprising:

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• a capacitor;
• a charger that charges the capacitor with a supply of power from a commercial power supply;
• a heating member that produces heat with a supply of charging power from the capacitor;
• a terminal-voltage detecting circuit that detects a terminal voltage of the capacitor;
• a control unit that controls the charger based on the terminal voltage detected to charge the capacitor;
• a power controller that stops, when a predetermined condition is satisfied, a power supply to a part of power loads of the heating unit including the control unit, and releases, when a predetermined condition is satisfied during a stop state of the power supply, the stop state;
• and
• a charge controller that controls, during the stop state of the power supply, the charger to charge the capacitor based on the terminal voltage detected.

An image forming apparatus that forms an image on a medium using an electrophotographic method, the image forming apparatus comprising a fixing unit that includes

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• a capacitor;
• a charger that charges the capacitor with a supply of power from a commercial power supply;
• a heating member that produces heat with a supply of charging power from the, capacitor;
• a terminal-voltage detecting circuit that detects a terminal voltage of the capacitor;
• a control unit that controls the charger based on the terminal voltage detected to charge the capacitor;
• a power controller that stops, when a predetermined condition is satisfied, a power supply to a part of power loads of the heating unit including the control unit, and releases, when a predetermined condition is satisfied during a stop state of the power supply, the stop state;
• and
• a charge controller that controls, during the stop state of the power supply, the charger to charge the capacitor based on the terminal voltage detected.

A heating unit comprising:

• a capacitor;
• a charger that charges the capacitor;
• a heating member;
• a discharger that discharges charging power of the capacitor to the heating member to make the heating member produce heat;
• a first control unit that stops, when a predetermined condition is satisfied, a power supply to other power loads except for a part of power loads of the heating unit, and releases, when the predetermined condition is satisfied during a stop state of the power supply, the stop state;
• and
• a second control unit that is driven with a supply of power independently from the first control unit, and controls charging of the capacitor.

A fixing unit comprising:

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• a first heating member that produces heat with a supply of power from a commercial power supply, and heats the fixing member;
• a capacitor;
• a charger that charges the capacitor with a supply of power from the commercial power supply;
• a second heating member that produces heat with a supply of power from the capacitor, and heats the fixing member;
• a first control unit that stops, when a predetermined condition is satisfied, a power supply to other power loads except for a part of power loads of the heating unit, and releases, when the predetermined condition is satisfied during a stop state of the power supply, the stop state;
• and
• a second control unit that is driven with a supply of power independently from the first control unit, and controls charging of the capacitor.

An image forming apparatus that forms an image on a medium using an electrophotographic method, the image forming apparatus comprising a fixing unit that includes

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• a first heating member that produces heat with a supply of power from a commercial power supply, and heats the fixing member;
• a capacitor;
• a charger that charges the capacitor with a supply of power from the commercial power supply;
• a second heating member that produces heat with a supply of power from the capacitor, and heats the fixing member;
• a first control unit that stops, when a predetermined condition is satisfied, a power supply to other power loads except for a part of power loads of the heating unit, and releases, when the predetermined condition is satisfied during a stop state of the power supply, the stop state;
• and
• a second control unit that is driven with a supply of power independently from the first control unit, and controls charging of the capacitor.

An auxiliary power unit comprising:

• a first capacitor;
• a first charger that charges the first capacitor with a supply of power from the commercial power supply;
• a first terminal-voltage detection circuit that detects a terminal voltage of the first capacitor;
• a second capacitor serially connected to the first capacitor;
• a second charger that charges the second capacitor with a supply of power from the commercial power supply;
• a second terminal-voltage detection circuit that detects a terminal voltage of the second capacitor;
• and
• a control unit that switches a charging operation between the first charger and the second charger so that the terminal voltage reaches a final target voltage based on results of detection by the first terminal-voltage detection circuit and the second terminal-voltage detection circuit.

A fixing unit comprising:

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• first heating member that produces heat with a supply of power from a commercial power supply, and heats the fixing member;
• and
• a second heating member that produces heat with a supply of power from a first capacitor and a second capacitor in an auxiliary power unit, wherein
• the auxiliary power unit includes
• the first capacitor;
• a first charger that charges the first capacitor with a supply of power from the commercial power supply;
• a first terminal-voltage detection circuit that detects a terminal voltage of the first capacitor;
• the second capacitor serially connected to the first capacitor;
• a second charger that charges the second capacitor with a supply of power from the commercial power supply;
• a second terminal-voltage detection circuit that detects a terminal voltage of the second capacitor;
• and
• a control unit that switches a charging operation between the first charger and the second charger so that the terminal voltage reaches a final target voltage based on results of detection by the first terminal-voltage detection circuit and the second terminal-voltage detection circuit.

An image forming apparatus that forms an image on a medium using an electrophotographic method, the image forming apparatus comprising a fixing unit that includes

• a fixing member that applies pressure and heat to a medium, on which a toner image is formed, to fix the toner image on the medium;
• first heating member that produces heat with a supply of power from a commercial power supply, and heats the fixing member;
• and
• a second heating member that produces heat with a supply of power from a first capacitor and a second capacitor in an auxiliary power unit, wherein
• the auxiliary power unit includes
• the first capacitor;
• a first charger that charges the first capacitor with a supply of power from the commercial power supply;
• a first terminal-voltage detection circuit that detects a terminal voltage of the first capacitor;
• the second capacitor serially connected to the first capacitor;
• a second charger that charges the second capacitor with a supply of power from the commercial power supply;
• a second terminal-voltage detection circuit that detects a terminal voltage of the second capacitor;
• and
• a control unit that switches a charging operation between the first charger and the second charger so that the terminal voltage reaches a final target voltage based on results of detection by the first terminal-voltage detection circuit and the second terminal-voltage detection circuit.