Heater and image forming apparatus
AssigneesToshiba Tec Kabushiki Kaisha, Toshiba Hokuto Electronics Corporation
InventorMasao ANDO
Life of this patent
Estimating the term…
Abstract
According to one embodiment, a heater has a base member, a heat generating resistor, a wiring and a switch. Three or more electrodes are disposed on the base member to be spaced apart from each other in a longitudinal direction of the base member. The heat generating resistor electrically interconnects electrodes which form an electrode pair and face each other in the longitudinal direction among the electrodes. The wiring connects the electrodes forming the electrode pair to have different polarities from each other. The switch is connected to the wiring and configured to select an electrode to which a voltage is to be applied.
Claims10
A heater comprising:
- a base member;
- three or more electrodes disposed on the base member to be spaced apart from each other in a longitudinal direction of the base member;
- a heat generating resistor which electrically interconnects electrodes which form an electrode pair and face each other in the longitudinal direction among the electrodes;
- a wiring which connects the electrodes forming the electrode pair to have different polarities from each other;
- and
- a switch connected to the wiring and configured to select an electrode to which a voltage is to be applied.
An image forming apparatus comprising:
- a base member;
- three or more electrodes disposed on the base member to be spaced apart from each other in a longitudinal direction of the base member;
- a heat generating resistor which electrically interconnects electrodes which form an electrode pair and face each other in the longitudinal direction among the electrodes;
- a wiring which connects the electrodes forming the electrode pair to have different polarities from each other;
- a switch connected to the wiring and configured to select an electrode to which a voltage is to be applied;
- and
- a fixing controller configured to control an operation of the switch.
An image forming apparatus comprising:
- a base member;
- three or more electrodes disposed on the base member to be spaced apart from each other in a longitudinal direction of the base member;
- a heat generating resistor which electrically interconnects electrodes which form an electrode pair and face each other in the longitudinal direction among the electrodes;
- a wiring which connects the electrodes forming the electrode pair to have different polarities from each other;
- a switch connected to the wiring and configured to select an electrode to which a voltage is to be applied;
- a voltage adjuster connected to the wiring and configured to change a voltage applied to at least one electrode pair among a plurality of electrode pairs according to a control signal;
- a fixing belt configured to be heated due to heat generation of the heat generating resistor;
- a temperature detector configured to detect a temperature of the fixing belt at a plurality of positions in a conveyance perpendicular direction;
- and
- a fixing controller configured to;
- select a heat generating region in the longitudinal direction according to a sheet size;
- control an operation of the switch to supply power to the heat generating resistor corresponding to the heat generating region already being heated among the heat generating resistors;
- and
- by use of the voltage adjuster, increase the voltage to be applied to the electrode pair to which the heat generating resistor, to which power has been supplied, is connected, in the case where a detection output of the temperature detector detecting a temperature in the heat generating region is equal to or less than a threshold value.
Dependencies are inferred from the claim text.