Canon Kabushiki Kaisha

Shinji Hashiguchi

Satoru Izawa

Koji Nihonyanagi

Akihito Kanamori

Eiji Uekawa

Hiroshi Kataoka

Fumiki Inui

Masato Sako

Munehito Kurata

Hiroto Hasegawa

Kenji Kanari

Tohru Saito

Yutaka Kubochi

Ryo Suzuki

Yuki Nishizawa

Toshihiko Ochiai

Masahide Hirai

Eiichiro Kimizuka

Yasuhisa Matsumoto

Shizuma Nishimura

Yusuke Hirota

Masataka Mochiduki

Hiroshi Kita

Tatsuya Kobayashi

Takehiko Suzuki

Akira Kuroda

Aoji Isono

Michio Uchida

Mahito Yoshioka

Keisuke Mochizuki

Koichi Hiroshima

Jun Asami

Satoshi Murasaki

Shoichiro Ikegami

Toshiya Kaino

Masami Takeda

Yusuke Jota

Hiroki Eguchi

Koji Uchiyama

Kentaro Yamashita

Hisahiro Saito

Yuko Tanaka

Takao Kawadu

An image forming apparatus that forms an image on a recording material has a second image forming mode that (i) controls the target control temperature of a heater to be lower than in a normal image forming mode and at least (ii) extends a period of time from the start of image forming to a point of time at which the recording material reaches the nip portion to be longer than in the normal image forming mode based on (A) recording material information indicating the hardness of the recording material, at least one of (B) margin information indicating the size of the margin at the leading end in the transport direction of the recording material and (C) toner amount information at the leading end of the image formed on the recording material, and (D) information of an environment in which the image forming apparatus is installed.

Image forming apparatus that conditionally extends a preparatory rotation time until a recording material enters a fixing portion

An image forming apparatus includes a fixing unit to fix a toner image which has been transferred onto a sheet by a transfer portion, a loop detector to detect an amount of a loop formed on the sheet at a position between the transfer portion and the fixing unit, and a controller to control a sheet conveyance speed of the fixing unit based on a detection result of the loop detector and control a rotational speed of rotary members to convey the sheet based on an area ratio which is a ratio of an area in which the toner image is formed by the transfer portion within a predetermined region set on a printing surface of the sheet onto which the toner image is transferred. The predetermined region is located at a position distant from a leading edge of the sheet more than a distance between the transfer portion and the fixing unit in the sheet conveyance direction.

Image forming apparatus having sheet loop control

In a warm-up period of a fixing apparatus of the present disclosure, a control unit supplies first electric power to a heater and thereafter supplies second electric power larger than the first electric power to the heater. The timing of starting to supply the second electric power is determined according to the degree of an increase in temperature sensed by a temperature sensing member after a driving signal is transmitted to a driving source.

Fixing apparatus

An image forming apparatus includes a position deviation detection unit configured to detect a position deviation of a recording medium in a width direction of the recording medium in a current job on a basis of (a) an amount of change over time in a difference between temperature detected by a first temperature detection element and temperature detected by a second temperature detection element and (b) information on temperature distribution on a fixing unit that occurred before the current job.

Image forming apparatus

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

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.

An image heating apparatus for heating an image formed on a recording material includes a tubular rotary member including a conductive layer, a magnetic core inserted into a hollow portion of the rotary member, a coil helically wound around an outer side of the magnetic core in the hollow portion, and a control unit configured to control a frequency of an alternating current flowing through the coil, in which the conductive layer generates heat by an electromagnetic induction in an alternating magnetic field formed when the alternating current flows through the coil, and the control unit controls the frequency in accordance with a size of the recording material.

Image heating apparatus

An image heating apparatus for heating an image formed on a recording material includes: a cylindrical rotatable member including a base layer and an electroconductive layer; a core inserted into the rotatable member; and a coil wound helically around the core inside the rotatable member, wherein an AC magnetic field is formed by passing an AC current through the coil to generate heat in the electroconductive layer through electromagnetic induction heating. The base layer has a volume resistivity higher than a volume resistivity of the base layer. The electroconductive layer generates heat through a full circumference thereof by a current flowing in a circumferential direction of the rotatable member independently of rotation of the rotatable member.

Image heating apparatus and rotatable member for use with the image heating apparatus

A fixing device fixes an image on a sheet, and includes a rotatable member having an electroconductive layer; a helical coil provided inside the rotatable member and having a helix axis extending in a generatrix direction of the rotatable member; a magnetic member provided inside a helical configuration portion formed by the coil, the magnetic member not forming a loop outside the rotatable member; and a controller for controlling electric power supplied to the coil. The electroconductive layer generates heat by electromagnetic induction caused by the magnetic flux produced by an alternating current through the coil to fix the image on the sheet by the heat from the rotatable member. The controller limits the maximum electric power supplied to the coil, in accordance with the temperature of the magnetic member.

Fixing device and image forming apparatus

A fixing device includes: a rotatable member including an electroconductive layer; a helical coil having a helical axis direction along a generatrix direction of the rotatable member; a magnetic member not forming a loop outside the electroconductive layer; a frequency setting portion for setting a frequency of an AC current caused to flow through the coil; and a temperature detecting portion for detecting a temperature of the rotatable member, including a first temperature detecting member and a second temperature detecting member. The electroconductive layer generates heat through electromagnetic induction heating by magnetic flux resulting from the AC current, and an image is fixed on a recording material by heat of the rotatable member. The frequency setting portion sets the frequency depending on a value of a difference between a detection temperature of the first temperature detecting member and a detection temperature of the second temperature detecting member.

Heat-fixing device

The fixing apparatus includes a sleeve, a nip portion forming member that contacts an inner surface of the sleeve, a pressure member, and a regulation member for regulating movement of the sleeve. The regulation member includes a first surface and a second surface. The first surface on an upstream side of the nip portion in a conveyance direction of the recording material includes a region in which the distance between the inner surface of the sleeve and the first surface in a radial direction of the sleeve increases toward a center portion of the sleeve in the generatrix direction, and in which the end surface of the sleeve contacts the region when the sleeve moves in the generatrix direction.

In an image forming apparatus, to provide a lubrication effect for an abutment portion of a transfer belt and a belt cleaning blade, when a control toner image is supplied, the control toner image is supplied to the abutment portion even when it is not necessary, thereby consuming a large amount of toner. In the image forming apparatus, the control unit changes a toner amount of the control toner image reaching the abutment portion of a photosensitive member and a photosensitive member cleaning blade and the toner amount thereof reaching the abutment portion of a transfer belt and a belt cleaning blade, based on a detection result of an environment detection unit.

Image forming apparatus capable of reducing a toner consumption amount by performing toner supply control

An image forming system includes an image forming apparatus including a heating fixing portion and a host computer capable of instructing printing. In the image forming apparatus, throughput can be changed and discriminated in accordance with a printing number. For printing on small size sheets, the system is operable in a normal small size sheet mode and in a high speed small size sheet output mode, in which the printing is effected at a throughput which is higher than that in the normal small size sheet mode and, after completion of the printing, the image forming apparatus rests for a predetermined rest period. The host computer includes a mode selector for selecting a mode from the high speed small size sheet output mode and the normal small size sheet mode, and a controller for transmitting the mode selected by the mode selector to the image forming apparatus.

Image forming system and apparatus with different printing modes for different numbers of printing sheets

An apparatus includes a controller controlling feeding of a recording material. When the recording material size is smaller than a reference size, the controller expands an interval between precedent and subsequent recording materials gradually. When image formation on recording materials smaller than a reference size starts, when the elapsed time from the end of the last image formation exceeds a predetermined time, an initial value of the interval is set to a predetermined minimum value. When image formation on recording materials smaller than the reference size starts, when the elapsed time is shorter than the predetermined time, the initial value of the interval is set in accordance with the elapsed time and a last feeding interval at the time of an image formation of the last time or a last temperature in a non-sheet-passing region at the time of an image formation of the last time.

Growing community of inventors

Mishima, Japan

Shinji Hashiguchi