Canon Kabushiki Kaisha

Oki Kitagawa

Masanobu Tanaka

Akiyoshi Shinagawa

Shigeaki Takada

Hiroki Kawai

Asuna Fukamachi

Yasuharu Chiyoda

Hiroto Ito

Yasuharu Toratani

Suguru Takeuchi

Keita Ishiguro

Masayuki Tamaki

Koichi Kakubari

According to one aspect of the present invention, an image forming apparatus includes a fixing unit comprising a fixing member configured to fix a toner image to a recording material, and a pressure member configured to form a first nip portion, a conveyance portion configured to form a second nip portion, and a control unit configured to execute, a conveyance mode of conveying the recording material so that the recording material is not looped between the first nip portion and the second nip portion prior to a predetermined timing during passing of the recording material of the first nip portion, and conveying the recording material so that the recording material is looped toward the pressure member from the predetermined timing until a trailing edge of the recording material has passed through the first nip portion.

Image forming apparatus having control unit that controls drive unit and conveyance portion

An image forming apparatus includes an image forming portion, an image heating apparatus including an image heating unit, a rotatable pressing roller, and an information storing portion; a reading portion; a counter portion; a display portion; and a controller. The controller controls the counter portion so that a) when the image heating apparatus mounted is exchanged with an image heating apparatus including a new image heating unit, on the basis of information of the information storing portion, the count value of the image heating apparatus, the count value of the image heating unit and the count value of the rotatable pressing member are reset, and b) when only the image heating unit mounted is exchanged with a new one, the count value of the image heating unit is reset and the count value of the rotatable pressing member is not reset.

Image forming apparatus

An image forming apparatus includes an executing portion for cleaning a rotatable heating member by introducing, into a nip, sheets, of a plurality of sheets, on which a predetermined toner image is formed by an image forming portion, a changing mechanism for making positional relationships of first and second sheets, of the plurality of sheets, relative to the rotatable heating member, different from each other with respect to a widthwise direction of the rotatable heating member when the first and second sheets are successively introduced into the nip in a cleaning mode, and a re-introducing mechanism for re-introducing the first and second sheets into the nip, the first and second sheets having passed through the nip and having been turned upside down, wherein the changing mechanism changes the relative positional relationship of the first and second sheets, which are turned upside down, relative to the rotatable heating member.

Image forming apparatus that executes a cleaning mode in which positional relationships of a first sheet and a second sheet, fed through a fixing nip during a cleaning mode, relative to a rotatable heating member differ from each other

An image forming apparatus includes an image forming unit, a fixing unit, a sheet discharge unit to stack sheets, an acquisition unit, and a controller. The fixing unit fixes a toner image formed on a sheet by the image forming unit. The acquisition unit acquires information corresponding to a maximum toner application amount per unit area of the formed toner image. The controller controls the number of image formations on the sheets per unit time based on the acquired information. The controller executes a first job with a first number of image formations on the sheets per unit time during a period from an Lth sheet to an Mth sheet in the first job, and executes a second job with a second and smaller number of image formations on the sheets per unit time during the period from the Lth to the Mth sheet in the second job.

A fixing device includes first and second rotatable members that form a nip for fixing a toner image on a recording material, and a pressing mechanism that presses one of the first and second rotatable members toward the other. A pressure P1 at a first position, in an upstream side of a center of a recording material feeding direction, and which is a maximum pressure in the nip, an average pressure P0 from the first position to a second position, which is a downstream end of the nip in the recording material feeding direction, a toner melt viscosity M1 at the first position, and a toner melt viscosity M2 at the second position, satisfy: 0.3 MPa&#x2264;P1&#x2264;0.6 MPa, 0&#x3c;P0&#x2264;0.25 MPa, 1.0&#xd7;10Pa&#xb7;s&#x2264;M1&#x3c;1.0&#xd7;10Pa&#xb7;s, and 0.5&#xd7;10Pa&#xb7;s&#x2264;M2&#x2264;1.0&#xd7;10Pa&#xb7;s.

Fixing device having a pressing mechanism that presses first and second rotatable members together

An image forming apparatus includes an image forming portion forming a toner image on a sheet, a rotatable heating member and a rotatable pressing member for fixing, at a nip, the toner image formed on the sheet by the image forming portion, an executing portion for executing a cleaning mode for cleaning the rotatable heating member by introducing, into the nip, the sheet on which a predetermined toner image is formed by the image forming portion, a re-introducing mechanism for re-introducing the sheet, into the nip, which has passed through the nip and then has been turned upside down, and a shifting mechanism for shifting a sheet position so that when a single sheet is introduced twice into the nip in the cleaning mode by using the re-introducing mechanism, positional relationships of a first-time sheet and a second-time sheet relative to the rotatable heating member with respect to a widthwise direction of the rotatable heating member are made different from each other.

An image forming apparatus includes an image forming unit, a human-body detection unit, an instruction receiver, and a controller. The controller determines whether an adjustment process is to be performed in accordance with a result of a determination, at an end of an image forming process, as to whether a human body is detected. The controller executes the adjustment process when the image forming process is terminated where the human-body detection unit does not detect a human body. The controller starts the image forming process before the adjustment process is executed where a human body is detected and the image forming instruction is received within a predetermined period. The controller executes the adjustment process when the predetermined period has elapsed while the image forming instruction is not received after the end of the image forming process where the human-body detection unit detects a human body.

An image forming apparatus includes an image forming portion for forming an image, a human presence sensor for detecting presence of a human body adjacent the apparatus, and a controller capable of executing an adjustment process operation for the image forming portion when a first predetermined number of prints are produced. When the human presence sensor detects a human body in the neighborhood of the apparatus, the execution of the adjustment process operation is deferred to reduce the waiting time necessitated by the adjustment operation, but if a second predetermined number of prints are produced, the image forming operation of the image forming portion is interrupted, and the deferred adjustment process is executed.

Image forming apparatus and control device therefor

An image forming apparatus includes: an image forming device configured to form a toner image on a sheet; a fixing device configured to fix the toner image formed on the sheet by the image forming device at a nip; an executing portion configured to execute an operation in a cleaning mode for cleaning the fixing device by forming a predetermined toner image on a sheet using the image forming device and then by introducing the sheet into the nip; and a notifying device for notifying an operator that a maximum-width sheet usable in the image forming device is to be used in the operation in the cleaning mode.

Image forming apparatus with cleaning mode

An image forming apparatus includes an image forming device for forming an image on a sheet; a fixing device for fixing an image formed on a sheet; a detector for detecting a temperature of the fixing device, and a controller for controlling an image formation start timing in accordance with an output of the detector. In an operation of continuously forming images on a plurality of predetermined sheets, when a number of image formations is not less than a predetermined number, the start of the image formation is delayed until a temperature of the fixing device rises up to a first temperature, and when the number of image formations is less than the predetermined number, the image formation is started when the temperature of the fixing device rises up to a second temperature which is lower than the first temperature.

Image forming apparatus controlling the operation speed of each of an image forming portion and a fixing portion thereof when an image formation process is continuously performed for a plurality of sheets

An image heating apparatus includes: an image heating roller in a nip; a nip forming member; a heating roller rubbing roller; a moving mechanism for moving the rubbing roller between a spaced position and a rubbing position; and a controller for executing operations in first and second modes. In the first mode, the heating roller is rotated with the rubbing roller in the spaced position and the heating roller in contact with the nip forming member with a target temperature of the heating roller higher than that of the nip forming member. In the second mode, the rubbing roller is contacted with the heating roller, rubbing the surface of the heating roller. The temperature difference in the first mode between the target temperature of the heating roller and that of the nip forming member is larger than the temperature difference when the toner image is heated by the nip.

Image heating apparatus

An image forming apparatus includes: heating and pressing rollers for fixing a toner image; a contacting and spacing portion for contacting and spacing between the rollers; an air feeder for cooling the pressing roller during a job; a guide for the sheet having been subjected to an image fixing process; an acquiring portion for acquiring the temperature of the guide: and an executing portion for executing a warming-up process of the heating roller and the pressing roller to raise the temperatures of the heating roller and the pressing roller. The executing portion controls the contacting and spacing portion and the air feeder so that the air is fed toward the guide through between the heating roller and the pressing roller at least in a part of the warming-up process, when the temperature is lower than a predetermined temperature upon activation of a main voltage source.

An image heating apparatus includes a heating roller; a nip forming member for forming the nip with the roller; a sheet jam sensor; a first controller for interrupting a heating operation when the sensor detects the sheet jamming, and for resuming the heating operation after the jamming is cleared; a rubbing member for rubbing a heating roller surface; a moving mechanism for moving the rubbing member to a position for spacing the rubbing member from the roller to a position for rubbing the roller surface; and a second controller for executing an operation of moving the rubbing member to the rubbing position to rub the heating roller surface when a predetermined condition is reached, wherein the second controller delays, when the condition is reached during a period in which a predetermined count of sheets pass the nip after the jam clearance, the moving operation to after the period.

A fixing apparatus includes: a rotatable fixing member and a rotatable pressing member which are configured to fix a toner image on a sheet at a nip therebetween, wherein the rotatable fixing member has a first toner parting layer formed of a fluorine-containing resin material, and the rotatable pressing member has a second toner parting layer formed of a fluorine-containing resin material in which an electroconductive filler is contained; and a contact member provided contactable to the second toner parting layer and being electrically grounded. The second toner parting layer has surface resistivity lower than that of the first toner parting layer and has a thickness smaller than that of the first toner parting layer.

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Nagareyama, Japan

Oki Kitagawa