Canon Kabushiki Kaisha

Kohei Wakatsu

Kazuhiro Doda

Tsuguhiro Yoshida

Yutaka Sato

Takashi Narahara

Takeshi Shinji

Ken Nakagawa

Toru Imaizumi

Ken Oi

Jun Miura

Atsushi Nakamoto

Toshiyuki Watanabe

Koji An

Nozomu Nakajima

A heating apparatus includes a fixing film and a heater in the inner space of the fixing film. The heater includes a long narrow substrate and at least two or more heating elements with different lengths in a longitudinal direction. The heating apparatus further includes first and second temperature detection units configured to detect a temperature of the heater and a control unit configured to set the power ratio between a first heating element and a second heating element in response to the detection result of the second temperature detection unit.

Heating apparatus and image forming apparatus

A fixing unit includes a film, a nip forming member, a heating unit, a rotary member arranged to sandwich the film together with the nip forming member, and an end portion regulating member configured to be in sliding contact with the film and to regulate an end portion of the film in the longitudinal direction. The end portion regulating member includes a first surface facing an inner surface of the film, a second surface facing an end face of the film in the longitudinal direction, and a third surface facing an outer surface of the film and configured to regulate the end portion of the film from deforming in a manner separating from the first surface. An entirety of the third surface is disposed on an upstream side of a center position of the nip portion in a conveyance direction of the recording material in the nip portion.

Fixing unit with a film regulating surface disposed upstream of the center of a nip portion and image forming apparatus

The heater including a substrate, a first heat generation member, a second heat generation member having a length substantially a same in a longitudinal direction as a length of the first heat generation member, a third heat generation member having a length shorter than lengths of the first heat generation member and the second heat generation member in the longitudinal direction, and a fourth heat generation member having a length shorter than length of the third heat generation member in the longitudinal direction, wherein the first heat generation member, the second heat generation member, the third heat generation member and the fourth heat generation member are arranged on the substrate.

Heater including a plurality of heat generation members, fixing apparatus, and image forming apparatus

A fixing device includes a heater provided with a first heat generator on a substrate and a second heat generator of which a length in a longitudinal direction is shorter than that of the first heat generator, a temperature detector of the heater, a switch for switching a power supply path from an AC power source to the first heat generator or the second heat generator. A controller for controlling the switch to supply power to the first heat generator or the second heat generator. The controller executes a first control in which the switch supplies the power to the first heat generator, and switches a second control in which the switch supplies the power alternately to the first heat generator or the second heat generator when the detected temperature reaches a threshold temperature.

Fixing device provided with heater and image forming apparatus

A fixing apparatus including: a first rotary member; a second rotary member; a nip forming member; and a heater. The nip forming member includes: a first projection portion inside a nip area; and a second projection portion located outside the nip area. The first and second projection portion abut against the inner circumferential surface of the first rotary member. In a direction orthogonal to a nip tangent, a distance between a tip of the second projection portion and the nip tangent is larger than a distance between a tip of the first projection portion and the nip tangent. The second projection portion extends toward the second rotary member without exceeding the nip tangent. A radius of curvature at a tip portion of the second projection portion is smaller than a radius of an inner circumferential circle of the first rotary member.

Fixing apparatus having a nip area, and image forming apparatus

A fixing unit includes a tubular film, a pressure roller, a heater including a first heating element and a second heating element, a detector configured to detect a temperature of the heater, a switcher configured to switch which of the first heating element and the second heating element is supplied power from a power supply, and a controller configured to control the switcher. The controller is configured to execute a first control of determining a first electric energy and a second electric energy based on the temperature of the heater detected by the detector and a target temperature of the heater, and a second control of causing the switcher to switch between a state in which power is supplied to the first heating element by the first electric energy and a state in which power is supplied to the second heating element by the second electric energy.

Fixing unit and image forming apparatus

A fixing device includes a substrate, a first heat generator, a second heat generator with a length in a longitudinal direction of the substrate equal to a length of the first heat generator; and a third heat generator with a length shorter than the lengths of the first and second heat generators, a soaking member with a positioning portion in the longitudinal direction. In a short side direction of the substrate, the first heat generator is arranged at one end side, the second heat generator is arranged at the other end side, and the third heat generator is arranged between the first and second heat generators. The soaking member is arranged between the heater and a holder in a thickness direction. As seen in the short side direction, the positioning portion is positioned outside of an area corresponding to the third heat generator and inside of an area corresponding to the first heat generator.

An image forming apparatus includes a first rotating member, a heater, a second rotating member, a detecting unit, a switching unit, a controlling unit, and a power source device. In a first period, a resultant current of first and third currents is supplied to a first heat generating element, and the resultant current in a unit cycle of a first period is a current at which a first current supplying timing and timings of a maximum and a minimum of the third current do not overlap with each other. In a second period, a resultant current of second and third currents is supplied to a second heat generating element, and the resultant current in a unit cycle of the second period is a current at which a second current supplying timing and the timings of the maximum and the minimum of the third current overlap with each other.

Image forming apparatus including heater powered with cycle-switched current and fixing device including the heater

An image forming apparatus includes a fixing device having a heater, a first temperature detection unit, a pair of second temperature detection units, a pair of first sheet-width detection units, a pair of second sheet-width detection units, and a control unit. The heater includes a first heat generating element, a second heat generating element having a length smaller than a length of the first heat generating element in a longitudinal direction, and a third heat generating element having a length smaller than the length of the second heat generating element in the longitudinal direction. The control unit controls a temperature of the heater based on a detection result of the pair of first sheet-width detection units, a detection result of the pair of second sheet-width detection units, and a detection result of the pair of second temperature detection units.

Image forming apparatus including a plurality of heat generating elements

An image forming apparatus is operable in a first small-sheet printing in which power is supplied to the first heat generating element and the second heat generating element and in a second small-sheet printing in which power is supplied to the first heat generating element and the third heat generating element. A first power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the second heat generating element in the first small-sheet printing, is higher than a second power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the third heat generating element in the second small-sheet printing.

Growing community of inventors

Kawasaki, Japan

Kohei Wakatsu