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US 12,455,521 B2Granted
Image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorAoji Isono
Life of this patent
Estimating the term…
Abstract
An image forming apparatus includes a fixing member, a heating portion configured to heat the fixing member by being supplied with electric power, a power source configured to supply electric power to the heating portion, a temperature detector, a controller configured to control power supply from the power source to the heating portion based on the output voltage from the temperature detector, a reference voltage generator configured to generate a reference voltage, and a breaker configured to stop the power supply from the power source to the heating portion. The reference voltage generator is configured to output the reference voltage that changes with time having elapsed since a start of heating at which the power supply to the heating portion was started by the controller.
Claims15
An image forming apparatus comprising:
- a fixing member configured to fix a toner image transferred onto a recording material, to the recording material by heating the toner image;
- a heating portion configured to heat the fixing member by being supplied with electric power;
- a power source configured to supply electric power to the heating portion;
- a temperature detector configured to output an output voltage that corresponds to a temperature of the fixing member or a temperature of the heating portion;
- a controller configured to control power supply from the power source to the heating portion based on the output voltage from the temperature detector, such that the temperature of the fixing member is maintained at a predetermined temperature;
- a reference voltage generator configured to generate a reference voltage;
- and
- a breaker configured to stop the power supply from the power source to the heating portion when a temperature that corresponds to the output voltage from the temperature detector becomes higher than a temperature that corresponds to the reference voltage,
- wherein the reference voltage generator is configured to output the reference voltage that changes with time having elapsed since a start of heating at which the power supply to the heating portion was started by the controller, such that a temperature corresponding to the reference voltage obtained when a first time has elapsed since the start of heating is lower than a temperature corresponding to the reference voltage obtained when a second time longer than the first time has elapsed since the start of heating, and
- wherein the reference voltage generator is configured to change the reference voltage such that the reference voltage changes linearly with the time having elapsed since the start of heating, from a low temperature side toward a high temperature side.
7 more elements
An image forming apparatus comprising:
- a fixing member configured to fix a toner image transferred onto a recording material, to the recording material by heating the toner image;
- a heating portion configured to heat the fixing member by being supplied with electric power;
- a power source configured to supply electric power to the heating portion;
- a temperature detector configured to output an output voltage that corresponds to a temperature of the fixing member or a temperature of the heating portion;
- a controller configured to control power supply from the power source to the heating portion based on the output voltage from the temperature detector, such that the temperature of the fixing member is maintained at a predetermined temperature;
- a reference voltage generator configured to generate a reference voltage;
- and
- a breaker configured to stop the power supply from the power source to the heating portion when a temperature that corresponds to the output voltage from the temperature detector becomes higher than a temperature that corresponds to the reference voltage,
- wherein the reference voltage generator is configured to output the reference voltage that changes with time having elapsed since a start of heating at which the power supply to the heating portion was started by the controller, such that a temperature corresponding to the reference voltage obtained when a first time has elapsed since the start of heating is lower than a temperature corresponding to the reference voltage obtained when a second time longer than the first time has elapsed since the start of heating, and
- wherein the reference voltage generator is configured to change the reference voltage such that the reference voltage changes along a curve that is convex toward a high temperature side or a low temperature side, with the time having elapsed since the start of heating.
7 more elements
An image forming apparatus comprising:
- a fixing member configured to fix a toner image transferred onto a recording material, to the recording material by heating the toner image;
- a heating portion configured to heat the fixing member by being supplied with electric power;
- a power source configured to supply electric power to the heating portion;
- a temperature detector configured to output an output voltage that corresponds to a temperature of the fixing member or a temperature of the heating portion;
- a controller configured to control power supply from the power source to the heating portion based on the output voltage from the temperature detector, such that the temperature of the fixing member is maintained at a predetermined temperature;
- a reference voltage generator configured to generate a reference voltage;
- a breaker configured to stop the power supply from the power source to the heating portion when a temperature that corresponds to the output voltage from the temperature detector becomes higher than a temperature that corresponds to the reference voltage;
- and
- an initial voltage holder configured to hold the output voltage from the temperature detector obtained at a start of heating at which the power supply to the heating portion was started by the controller, and provide a voltage corresponding to the output voltage to the reference voltage generator,
- wherein the reference voltage generator is configured to output the reference voltage that changes with time having elapsed since the start of heating at which the power supply to the heating portion was started by the controller, such that a temperature corresponding to the reference voltage obtained when a first time has elapsed since the start of heating is lower than a temperature corresponding to the reference voltage obtained when a second time longer than the first time has elapsed since the start of heating, and
- wherein the reference voltage generated by the reference voltage generator changes in accordance with the voltage given from the initial voltage holder.
8 more elements
Dependencies are inferred from the claim text.