Canon Kabushiki Kaisha

Yusuke Hirota

Akihiko Uchiyama

Shinji Hashiguchi

Hisashi Nakahara

Ryo Suzuki

Munehito Kurata

The present disclosure relates to an image forming apparatus that forms toner images on a recording material. A control unit is configured to set, when performing fixing processing to fix a toner image onto the recording material, a first mode where thermal generation distribution of the heater is switched in accordance with electric power supply to the heater, a second mode where thermal generation distribution of the heater is switched in accordance with the electric power supply to the heater and temperature at the non-sheet-passing portion, and a third mode where the blower unit is driven in accordance with temperature at the non-sheet-passing portion.

Image forming apparatus and fixing device

A controller of an image heating apparatus executes a first heater control operation, when a sheet having a width such that the sheet passes both a position of a first temperature detector and a position of a second temperature detector, is heated in a nip, for controlling power supply to a heater so that a temperature detected by the second temperature detector is maintained at a heater target temperature, and a second heater control operation, when a sheet having a width such that the sheet passes through the position of the first temperature detector, but does not pass through the position of the second temperature detector, is heated in the nip, for controlling the power supply to the heater, so that the temperature detected by the first temperature detector, irrespective of the temperature detected by the second temperature detector, is maintained at a film target temperature.

Image heating device including a controller that executes first and second heat controls based on temperatures detected by first and second detecting elements

In a first image formation mode, an image is formed with a first development contrast Cand a specific dot pattern is formed with a second development contrast C, which is lower than the first development contrast C; in a second image formation mode, an image is formed with a third development contrast Cand a specific dot pattern is formed with a fourth development contrast C, which is lower than the third development contrast C; and when &#x394;C(=C/C) denotes a ratio between the second development contrast Cand the first development contrast C, and &#x394;C(=C/C) denotes a ratio between the fourth development contrast Cand the third development contrast C, &#x394;C&#x3c;&#x394;Cis satisfied.

Image forming apparatus

An image heating apparatus for heating an image on a recording material. A controller executes a first heater control so that a temperature detected by a second temperature detecting element is maintained at a target temperature of the heater. The controller executes a second heater control for controlling the heater so that a temperature detected by a first temperature detecting element is maintained at a target temperature. When the first heater control is executed, the controller corrects the target temperature of the heater in accordance with the temperature detected by the first temperature detecting element, and when the second heater control is executed, a feeding speed of a recording material in a nip is less than that when the first heater control is executed.

In a first image formation mode, an image is formed with a first development contrast C1 and a specific dot pattern is formed with a second development contrast C2, which is lower than the first development contrast C1; in a second image formation mode, an image is formed with a third development contrast C3 and a specific dot pattern is formed with a fourth development contrast C4, which is lower than the third development contrast C3; and when &#x394;C1 (=C2/C1) denotes a ratio between the second development contrast C2 and the first development contrast C1, and &#x394;C2 (=C4/C3) denotes a ratio between the fourth development contrast C4 and the third development contrast C3, &#x394;C2&#x3c;&#x394;C1 is satisfied.

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Ebina, Japan

Yusuke Hirota