Canon Kabushiki Kaisha

Goichi Kitadai

Takahiro Uchiyama

Hisashi Nakahara

Yoshihiro Matsuo

Koji Uchiyama

Yoji Tomoyuki

Noriyuki Ito

Daisuke Miyagawa

In an image forming apparatus, the overall length of a heat generating resistor is set longer than the width of a recording paper, which is the greatest of widths of standard size recording papers that can be used on the image forming apparatus. An electrical resistance of an edge area of the heat generating resistor per unit length is set smaller than that of a center area of the heat generating resistor. The position of a boundary between the center area and the edge area is set so that the position of the side edge of the recording paper whose width is the greatest exists within the edge area and so that if the recording paper having the second greatest width is fed by a one edge-aligned paper feeding method, the position of the side edge of a recording paper whose width is the greatest of the widths of the standard size recording papers that can be used on the image forming apparatus except the width of the recording paper that is the greatest thereof is set at a position within the center area.

Image forming apparatus

The present invention relates to an image heating apparatus in which a nip portion is formed by a heating unit, which includes a flexible sleeve and a heater, and a pressure roller. The position of the heating unit is appropriately maintained by pressing the heating unit against the pressure roller using a pressure member so that the heating unit can contact two or more portions of a downstream side rim of a groove arranged on a frame that holds the heating unit, even when the pressure roller is rotated.

Image heating apparatus having stably positioned heating unit

Growing community of inventors

Suntou-gun, Japan

Goichi Kitadai