Canon Kabushiki Kaisha

Masahiko Suzumi

Toshio Miyamoto

Tomoo Akizuki

Satoru Izawa

Takeharu Nakada

Ryo Morihara

Masahiro Goto

Koji Nihonyanagi

Kenji Kanari

Tatsuya Kinukawa

Takehiko Suzuki

Takashi Narahara

Hiroto Hasegawa

Shoichiro Ikegami

Masahito Omata

Sho Taguchi

Takanori Watanabe

Kazuhiro Doda

Toru Imaizumi

Takanori Mitani

Jun Asami

Jun Hara

Yusuke Nakazono

Masami Takeda

Kenji Matsuzaka

Kazuaki Takahata

Toshihiko Ochiai

Jun Agata

Eiji Uekawa

Takayuki Kanazawa

Terutaka Endo

Takeshi Niimura

Akihito Kanamori

Ryukichi Inoue

Yozo Hotta

Shinji Kubo

Masatoshi Takiguchi

Junichi Kubota

Kouichi Yamada

Akiya Sato

A fixing apparatus includes a tubular film, an elongate plate-like heater including a first surface in contact with an inner surface of the film and a second surface opposite to the first surface, the heater being in contact with the inner surface of the film with the second surface, a heat conducting member that is long along the length of the heater and is in contact with the second surface of the heater, and a support member capable of rotating the film while supporting the heater, with the heat conducting member therebetween. The heat conducting member includes an extending portion extending, outside an upstream end of the heater in a rotational direction of the film, in a direction from the second surface of the heater toward the first surface. The extending portion includes a contact portion protruding from the first surface of the heater toward the film into contact therewith.

Fixing apparatus including a heat conducting member with an extending portion extending upstream of the heater

In a first operation mode in which a first addition value for each sheet of a recording material and a first initial control temperature, when the total sum of the first addition values exceeds a predetermined threshold value, a control portion of an image heating portion, which heats an image on the recording material, of an image forming apparatus changes the first initial control temperature to a first correction control temperature. When the operation mode is changed from the first operation mode to a second operation mode in which a second addition value different from the first addition value and a second initial control temperature different from the first initial control temperature, the control portion corrects the first correction control temperature based on a difference between initial control target temperatures.

Image forming apparatus that changes a control target temperature in accordance with a number of sheets of recording material that have passed through an image heating portion

A fixing apparatus includes a holding member including a groove-like holding portion, a heater supported by the holding portion, a film rotatable around the heater, the film being configured to be heated by sliding on the heater and to heat a toner image on a printing material, and a gap filling member including, on an upstream side with respect to the heater in a direction in which the circumferential surface of the film moves, a first portion disposed between the heater and the holding member and a first contact portion connecting to the first portion and being in contact with the film. A second distance between the first portion and the holding member disposed upstream from the first portion and facing the first portion is smaller than a first distance between the heater and the first portion disposed upstream from the heater and facing the holding member.

Fixing apparatus

A fixing device including a rotatable tubular film, a heater including a substrate and a heat generating resistor, the heater including a first surface in contact with an inner surface of the film and a second surface opposite to the first surface, the heater extending in a longitudinal direction of the substrate, and a heat conducting member extending in the longitudinal direction and including a heater contact portion in contact with the second surface. The heat conducting member includes a film contact portion at a position adjacent to the first surface, the film contact portion being in contact with the inner circumferential surface, and on one side in the longitudinal direction, the heat generating resistor extends outside of a longitudinal end portion of the film contact portion, and the heater contact portion extends outside of the film contact portion.

Fixing device

An image forming apparatus includes an image forming portion, a fixing portion, a temperature detecting portion, a measuring portion, a storing portion, and a controller. The controller is capable of setting a case that a start of feeding of a recording material is permitted after a lapse of a predetermined time need to measure a temperature rising rate of the fixing portion and a case that the start of feeding of the recording material is permitted, depending on a value relating to the temperature rising rate stored in the storing portion, at timing before the lapse of the predetermined time.

Image forming apparatus configured to set a start of a feeding operation based on a value related to a rate of temperature rise for a fixing portion

An image forming apparatus including: a charging member configured to charge a photosensitive member at a charging portion by a charging voltage in which an alternate-current voltage is superimposed on a direct-current voltage; a transfer member configured to transfer a toner image formed on the photosensitive member to a recording material at a transfer portion; and a controller configured to control the charging voltage, a predetermined area of the photosensitive member passing through the transfer portion during a trailing edge of the recording material passing through the transfer portion, wherein the controller controls a value of a peak-to-peak voltage of the alternate-current voltage when the predetermined area passes through the charging portion to be larger than a value of a peak-to-peak voltage when an area that becomes the image area other than the predetermined area passes through the charging portion.

Image forming apparatus

The image forming apparatus prevents a transfer roller from slipping when discharge processing for supplying toner to a contact portion between a photosensitive drum and a cleaning blade is performed. The developing unit performs transfer operation to form band-like toner images on a photosensitive drum to supply a predetermined amount of toner to a contact portion between the photosensitive drum and a cleaning blade without causing the transfer roller to perform transfer operation, so that the predetermined amount of toner is supplied in a plurality of batches.

Image forming apparatus performing toner purge processing

In one aspect of the invention, a fixing apparatus that heats a recording material having a toner image while conveying the recording material at a nip portion to make the toner image fix onto the recording material includes a cylindrical belt having a heat generating layer that generates heat by being energized and a contact for supplying electricity to the heat generating layer. The contact is in contact with one of an outer surface and an inner surface of an end of the belt in the generatrix direction of the belt. An electrically conductive layer is provided, along the direction of rotation of the belt, on a surface of the heat generating layer opposite to a surface of the heat generating layer at which the contact is present.

An image forming apparatus includes an image bearing member; a transfer unit for transferring a toner image from the image bearing member onto the recording material; a fixing unit for fixing the toner image on the recording material; an electroconductive member contactable to the recording material; a resistance element connected with the electroconductive member; and a capacitor element connected with the electroconductive member. The electroconductive member is disposed so as to be nipped simultaneously by the transfer nip and the fixing nip and so as to be contacted by the recording material, and the electroconductive member and the capacitor element are connected in parallel between the electroconductive member and a ground potential.

The fixing device includes a rotary member for contacting the unfixed toner image, a pressure member for forming the nip portion by contacting the rotary member, and a cover for covering the rotary member with a space between the rotary member and the cover. In a cross section of the fixing device, the cross section being orthogonal to a generatrix direction of the rotary member, the shortest distance (H) between the nip portion and a farthest surface portion of the rotary member farthest away from a surface portion forming the nip portion of the rotary member, the maximum width (W) of the rotary member in the conveyance direction of the recording member, and an area (S) of the space in a range of the maximum width W in the cross section satisfy with a relationship of S/W&#x2267;0.7&#xd7;H.

A fixing apparatus configured to heat a recording material having a toner image formed thereon and fix the toner image fixing on the recording material comprising: a film; a heater configured to contact the film, the heater including a substrate and a heat generation resistor formed on the substrate; a thermal conduction member configured to contact a surface of the heater opposite to a surface of the heater that contacts the film, the thermal conduction member having a thermal conductivity higher than that of the substrate; and a pressurizing roller configured to form a pressing portion with the heater via the film, wherein the thermal conduction member contacts the heater so as not to overlap with an end region of the heat generation resistor in a longitudinal direction of the heat generation member.

A fixing device includes a tubular film; a heater including a substrate and a heat generating resistor, the heater having a first region on which the heat generating resistor is formed and a second region, located outside of the first region in a longitudinal direction of the substrate, on which the heat generating resistor is not formed; and a heat conductive member configured to contact a surface of the heater opposite to a surface of the heater that contacts the film, the heat conductive member having a higher heat conductivity than the substrate. The heat conductive member contacts the heater in a region extending across the first region and the second region, and an amount of heat generated by the heat generating resistor at its end portion is greater than that at its middle portion in the longitudinal direction.

Fixing device of an image forming apparatus

A fixing rotational body is rotated immediately before shifting from a standby mode to a power saving mode in which not only power supply to a heater and the rotation of the fixing rotational body are stopped but also a timer is stopped so that the reliability of the thermistor detection temperature when returning from the power saving mode is improved, and fixing defect is prevented while power consumption in the power saving mode is reduced.

Image forming apparatus for shifting to a power saving mode after a lapse of a predetermined time

A reversely-rotatable roller conveys a sheet having an image formed on its one side at a sheet conveying velocity faster than that of a conveying roller by normal rotation and then, the reversely-rotatable roller conveys the sheet to a re-conveying path by reverse rotation. The sheet conveying velocity of the reversely-rotatable roller when the reversely-rotatable roller reversely rotates is made slower than the sheet conveying velocity when the reversely-rotatable roller normally rotates so that the sheet conveying velocity of the re-conveying roller is substantially equal to or slower than the sheet conveying velocity of the conveying roller.

Growing community of inventors

Yokohama, Japan

Masahiko Suzumi