Patents by Inventor Kazuhiro Doda
Kazuhiro Doda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11947290Abstract: An image forming apparatus includes first and second rotatable members forming a nip therebetween, a heater disposed in inside of the second rotatable member, a first temperature sensor provided on a center of the heater, a second temperature sensor provided on an end side of the heater. A controller controls a feeding interval in which a trailing edge of a preceding sheet passes through the nip until a leading edge of a subsequent sheet reaches the nip. The controller controls the feeding interval to be a first interval in a case which a feeding speed of the sheet is a first speed and a detected temperature by the second sensor is a first temperature, and to be a second interval shorter than the first interval in a case which the feeding speed is a second speed lower than the first speed and the detected temperature is the first temperature.Type: GrantFiled: August 5, 2022Date of Patent: April 2, 2024Assignee: Canon Kabushiki KaishaInventors: Atsushi Nakamoto, Kazuhiro Doda
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Publication number: 20230400803Abstract: 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.Type: ApplicationFiled: August 28, 2023Publication date: December 14, 2023Inventors: Kazuhiro Doda, Ken Nakagawa, Tsuguhiro Yoshida, Yutaka Sato, Kohei Wakatsu
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Publication number: 20230350328Abstract: An image forming apparatus includes a fixing unit including a tubular film, a pressure roller, and a heater including a heating element. The apparatus further includes a control unit configured to calculate an accumulated electrical energy supplied to a portion of the heating element. The portion of the heating element is located in an area corresponding to a second area of the nip portion. The second area is an area of the nip portion through which the recording material conveyed to the nip portion is not passed. The control unit is configured to determine an operation of heat leveling, which is performed for leveling a heat distribution in the nip portion after the recording material had passed the nip portion, based on the calculated accumulated electrical energy.Type: ApplicationFiled: July 5, 2023Publication date: November 2, 2023Inventor: Kazuhiro Doda
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Publication number: 20230314990Abstract: 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.Type: ApplicationFiled: June 6, 2023Publication date: October 5, 2023Inventors: Kohei Wakatsu, Kazuhiro Doda
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Patent number: 11774891Abstract: 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.Type: GrantFiled: August 9, 2022Date of Patent: October 3, 2023Assignee: Canon Kabushiki KaishaInventors: Kazuhiro Doda, Ken Nakagawa, Tsuguhiro Yoshida, Yutaka Sato, Kohei Wakatsu
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Patent number: 11774889Abstract: A fixing apparatus including a heat generating element having a first area, a second area, and a third area, the first area being located on an end portion side in an orthogonal direction orthogonal to a conveyance direction of a recording material and having a first heat generation amount per unit length in the orthogonal direction, the second area being located on an inner side than the first area in the orthogonal direction and having a second heat generation amount per unit length in the orthogonal direction, the third area being located on the inner side than the second area in the orthogonal direction and having a third heat generation amount per unit length in the orthogonal direction. The second heat generation amount is larger than the third heat generation amount, and the third heat generation amount is larger than the first heat generation amount.Type: GrantFiled: February 10, 2022Date of Patent: October 3, 2023Assignee: Canon Kabushiki KaishaInventors: Kazuhiro Doda, Tsuguhiro Yoshida, Atsushi Nakamoto, Shoichiro Ikegami
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Patent number: 11740576Abstract: An image forming apparatus includes a fixing unit including a tubular film, a pressure roller, and a heater including a heating element. The apparatus further includes a control unit configured to calculate an accumulated electrical energy supplied to a portion of the heating element. The portion of the heating element is located in an area corresponding to a second area of the nip portion. The second area is an area of the nip portion through which the recording material conveyed to the nip portion is not passed. The control unit is configured to determine an operation of heat leveling, which is performed for leveling a heat distribution in the nip portion after the recording material had passed the nip portion, based on the calculated accumulated electrical energy.Type: GrantFiled: March 2, 2022Date of Patent: August 29, 2023Assignee: Canon Kabushiki KaishaInventor: Kazuhiro Doda
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Publication number: 20230259057Abstract: 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.Type: ApplicationFiled: April 25, 2023Publication date: August 17, 2023Inventors: Kazuhiro Doda, Tsuguhiro Yoshida, Kohei Wakatsu
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Patent number: 11709446Abstract: 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.Type: GrantFiled: March 4, 2022Date of Patent: July 25, 2023Assignee: Canon Kabushiki KaishaInventors: Kohei Wakatsu, Kazuhiro Doda
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Patent number: 11669032Abstract: 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.Type: GrantFiled: November 2, 2021Date of Patent: June 6, 2023Assignee: Canon Kabushiki KaishaInventors: Kazuhiro Doda, Tsuguhiro Yoshida, Kohei Wakatsu
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Publication number: 20230064449Abstract: An image forming apparatus includes first and second rotatable members forming a nip therebetween, a heater disposed in inside of the second rotatable member, a first temperature sensor provided on a center of the heater, a second temperature sensor provided on an end side of the heater. A controller controls a feeding interval in which a trailing edge of a preceding sheet passes through the nip until a leading edge of a subsequent sheet reaches the nip. The controller controls the feeding interval to be a first interval in a case which a feeding speed of the sheet is a first speed and a detected temperature by the second sensor is a first temperature, and to be a second interval shorter than the first interval in a case which the feeding speed is a second speed lower than the first speed and the detected temperature is the first temperature.Type: ApplicationFiled: August 5, 2022Publication date: March 2, 2023Inventors: Atsushi Nakamoto, Kazuhiro Doda
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Patent number: 11531294Abstract: 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.Type: GrantFiled: November 29, 2021Date of Patent: December 20, 2022Assignee: Canon Kabushiki KaishaInventors: Tsuguhiro Yoshida, Kohei Wakatsu, Kazuhiro Doda, Yutaka Sato, Ken Nakagawa
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Publication number: 20220390882Abstract: 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.Type: ApplicationFiled: August 9, 2022Publication date: December 8, 2022Inventors: Kazuhiro Doda, Ken Nakagawa, Tsuguhiro Yoshida, Yutaka Sato, Kohei Wakatsu
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Patent number: 11507001Abstract: 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.Type: GrantFiled: July 8, 2021Date of Patent: November 22, 2022Assignee: Canon Kabushiki KaishaInventors: Tsuguhiro Yoshida, Kazuhiro Doda, Kohei Wakatsu
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Publication number: 20220308509Abstract: 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.Type: ApplicationFiled: March 4, 2022Publication date: September 29, 2022Inventors: Kohei Wakatsu, Kazuhiro Doda
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Publication number: 20220299914Abstract: An image forming apparatus includes a fixing unit including a tubular film, a pressure roller, and a heater including a heating element. The apparatus further includes a control unit configured to calculate an accumulated electrical energy supplied to a portion of the heating element. The portion of the heating element is located in an area corresponding to a second area of the nip portion. The second area is an area of the nip portion through which the recording material conveyed to the nip portion is not passed. The control unit is configured to determine an operation of heat leveling, which is performed for leveling a heat distribution in the nip portion after the recording material had passed the nip portion, based on the calculated accumulated electrical energy.Type: ApplicationFiled: March 2, 2022Publication date: September 22, 2022Inventor: Kazuhiro Doda
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Patent number: 11442385Abstract: 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.Type: GrantFiled: June 21, 2021Date of Patent: September 13, 2022Assignee: Canon Kabushiki KaishaInventors: Kazuhiro Doda, Ken Nakagawa, Tsuguhiro Yoshida, Yutaka Sato, Kohei Wakatsu
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Publication number: 20220253006Abstract: A fixing apparatus including a heat generating element having a first area, a second area, and a third area, the first area being located on an end portion side in an orthogonal direction orthogonal to a conveyance direction of a recording material and having a first heat generation amount per unit length in the orthogonal direction, the second area being located on an inner side than the first area in the orthogonal direction and having a second heat generation amount per unit length in the orthogonal direction, the third area being located on the inner side than the second area in the orthogonal direction and having a third heat generation amount per unit length in the orthogonal direction. The second heat generation amount is larger than the third heat generation amount, and the third heat generation amount is larger than the first heat generation amount.Type: ApplicationFiled: February 10, 2022Publication date: August 11, 2022Inventors: Kazuhiro Doda, Tsuguhiro Yoshida, Atsushi Nakamoto, Shoichiro Ikegami
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Patent number: 11281139Abstract: A fixing apparatus including a heat generating element having a first area, a second area, and a third area, the first area being located on an end portion side in an orthogonal direction orthogonal to a conveyance direction of a recording material and having a first heat generation amount per unit length in the orthogonal direction, the second area being located on an inner side than the first area in the orthogonal direction and having a second heat generation amount per unit length in the orthogonal direction, the third area being located on the inner side than the second area in the orthogonal direction and having a third heat generation amount per unit length in the orthogonal direction. The second heat generation amount is larger than the third heat generation amount, and the third heat generation amount is larger than the first heat generation amount.Type: GrantFiled: December 2, 2020Date of Patent: March 22, 2022Assignee: Canon Kabushiki KaishaInventors: Kazuhiro Doda, Tsuguhiro Yoshida, Atsushi Nakamoto, Shoichiro Ikegami
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Patent number: 11281135Abstract: In a case where fixing processing is performed continuously on sheets having a width that is shorter than a length of a heat generation member in a longitudinal direction and longer than a length of another heat generation member in the longitudinal directions, the CPU determines a timing to switch between the heat generation member and the another heat generation member by a heat generation member switching device based on information relating to a size of the sheet.Type: GrantFiled: January 15, 2021Date of Patent: March 22, 2022Assignee: Canon Kabushiki KaishaInventors: Yutaka Sato, Kazuhiro Doda, Kohei Wakatsu, Tsuguhiro Yoshida