Canon Kabushiki Kaisha

Haruhiko Omata

Tatsuomi Murayama

Shinya Suzuki

Masahiro Inoue

Yuichiro Toyohara

Yoichi Kimura

Akihiro Noguchi

Yoshikuni Ito

Takeshi Tomizawa

Yuji Bessho

Toru Katsumi

Yasuki Kamimori

Takashi Fujita

Takeshi Menjo

Hideaki Kosasa

Motohide Shiozawa

Yutaka Kakehi

Hiroshi Kokubo

Jiro Ishiduka

An image forming apparatus includes a heater including first and second heating members, the first heating member is longer than the second heating member in a widthwise direction. The image forming apparatus performs image formation on a first recording material shorter than the second heating member and a second recording material shorter than the first heating member and longer than the second heating member. In a case that first and second sheets are the first recording material, an electric power supplied to the first heating member is a first electric power while the first sheet passes through a nip, and in a case that the first sheet is the first recording material and the second sheet is the second recording material, the electric power is a second electric power smaller than the first electric power while the first sheet passes through the nip.

Image forming apparatus provided with heater including heat generating members with different lengths

An image forming apparatus includes an image forming unit, an intermediate transfer member, a transfer member, a power source, a fixing unit, a photo sensor photosensor, and a control unit configured to perform a mode to output a test chart which is formed by transferring a plurality of test toner images from the intermediate transfer member onto a plurality of sheets of the recording material, the test chart being used to adjust the transfer voltage applied to the transfer member. The control unit is configured to adjust the transfer voltage based on a detection result of the photo sensor photosensor detecting the plurality of test toner images recovered fixed on the recording material. In a case where a jam occurred during execution of the mode, the control unit is configured to resume the mode after the jam has been recovered.

Image forming apparatus

An image forming apparatus includes an image bearing member; a transfer member configured to transfer a toner image carried on the image bearing member to a sheet by being applied with a voltage; a controller configured to execute a mode of outputting a test chart for setting a voltage to be applied to the transfer member during image formation, the mode being a mode of transferring a plurality of test images to the test chart by applying a plurality of different voltages to the transfer member; and an operation portion capable of setting a type of a sheet on which the mode is executed. The controller is configured to preset a voltage value for setting a voltage to be applied when the test images are transferred in execution of the mode based on a voltage value, which is set in the previous execution of the mode.

Image forming apparatus with mode for setting transfer voltage

An image forming apparatus includes an image forming unit, an intermediate transfer member, a transfer member, a power source, a fixing unit, a photosensor, and a control unit configured to perform a mode to output a test chart which is formed by transferring a plurality of test toner images from the intermediate transfer member onto a plurality of sheets of the recording material, the test chart being used to adjust the transfer voltage applied to the transfer member. The control unit is configured to adjust the transfer voltage based on a detection result of the photosensor detecting the plurality of test toner images fixed on the recording material. In a case where a jam occurred during execution of the mode, the control unit is configured to resume the mode after the jam has been recovered.

An image forming apparatus includes an image forming unit, an intermediate transfer member, a power source, and a control unit configured to perform a mode to output a test chart which is formed by transferring a plurality of test toner images from the intermediate transfer member to a plurality of sheets of the recording material. In a case where a jam occurred during execution of the mode, the control unit is configured to resume the mode after the jam has been recovered. In a case where the control unit resumes the mode after the jam has occurred during the execution of the mode, the control unit is configured to resume the mode from a first sheet of the plurality of sheets of the recording material regardless of a number of sheets of the recording material not discharged due to the jam.

An image forming apparatus includes an image bearing member; a transfer member; and a controller configured to execute a plurality of modes of outputting a test chart, the modes involving transferring a plurality of test images to the test chart by applying a plurality of different voltages to the transfer member. The modes include a first mode and a second mode, the first mode being a mode in which a number of voltage levels to be applied to the transfer member when the plurality of test images are transferred to the test chart is a first predetermined number, and the second mode being a mode in which the number of voltage levels to be applied to the transfer member when the plurality of test images are transferred to the test chart is a second predetermined number which is greater than the first predetermined number.

An image forming apparatus includes an image bearing member, an image transfer device for transferring a toner image from the image bearing member to a sheet, an application device for applying a transfer voltage to the image transfer device, and a controller for controlling an output mode operation for outputting a predetermined chart in which test halftone toner images transferred with different transfer voltages are formed to adjust the transfer voltage. When outputting a maximum size of the chart, the controller forms the test toner images in a region within 50 mm from an edge in a width direction perpendicular to a feeding direction of the sheet.

Image forming apparatus outputting plural test toner images for use in adjusting transfer voltage

An image forming apparatus includes a controller configured to control a first and a second voltage applied to a transfer device when transferring an image to a first and a second side of a recording material, respectively. The controller controls a mode that outputs a test chart on which at least one of a plurality of first test images for adjusting the first voltage and a plurality of second test images for adjusting the second voltage is formed. In a case of forming the second test images on a second side of the test chart, and before forming the second test images, the controller forms a plurality of predetermined toner images under a same image forming condition on a first side of the test chart so that the predetermined toner images are formed on a plurality of predetermined areas overlapping each area where the second test images are to be formed.

Image forming apparatus using test chart for adjusting transfer voltage

An image forming apparatus includes an intermediary transfer member, a toner image forming unit, a rotatable transfer member, a cleaning unit, a feeding unit, a feeding portion and an executing portion configured to execute a supplying operation for supplying a supplying toner image to a cleaning portion. The executing portion forms the supplying toner image at a position including a position different from a position where an adjusting toner image for adjusting an image forming condition is formed, with respect to a widthwise direction crossing a movement direction of an intermediary transfer member provided in contact with the rotatable transfer member. The executing portion performs the supplying operation at least one time in a double-sided image forming job and does not perform the supplying operation in a single-sided image forming job.

When a drive roller is at a stopped state, an execution portion executes a move mode in which a time from when a rotation of a drive roller has been stopped is measured, and based on the measured result, rotation of the drive roller is started and stopped. In the move mode, a portion of a secondary transfer belt having been at a first contact position in the stopped state is moved to a position other than the first contact position and the second contact position, and the rotation of the drive roller is stopped.

An image forming apparatus includes a movable intermediary transfer member, a toner image forming unit, a rotatable transfer member, a fixing unit, a recording material feeding portion, an executing portion, and first and second cleaning units. The first cleaning unit includes a first brush roller, a first rotatable member and a first blade member. The second cleaning unit includes a second brush roller, a second rotatable member, a second blade member and a third blade member. The third blade member is disposed downstream of the cleaning portion and upstream of a contact portion, between the second rotatable member and the second brush roller, with respect to a rotational direction of the second rotatable member, and scrapes a deposited matter off the second rotatable member with the rotation of the second rotatable member.

An image forming apparatus includes: an image bearing member; a toner image forming unit; an endless transfer belt; a transfer roller urged from an inner peripheral surface of the transfer belt toward the image bearing member via the transfer belt; a feeding surface forming roller, provided downstream of the transfer roller with respect to a traveling direction of the transfer belt, having such a shape that a diameter at each of end portions is smaller than a diameter at a central portion with respect to a rotational axis direction; and a stretching roller, downstream of the feeding surface forming roller with respect to the traveling direction of the transfer belt, having such a shape that a diameter at each of end portions is larger than a diameter at a central portion with respect to the rotational axis direction.

Image forming apparatus having transfer belt rollers of specific shapes

Relationships of LB1&#x3e;LR1 and LN1&#x3c;LN2 are satisfied, where LB1 is a length of a first contact area in which a first brush roller and an endless belt come into contact with each other. LR1 is a length of a second contact area in which the first roller and the endless belt come into contact with each other. LN1 is a length of an area in which the first contact area and the second contact area overlap with each other. A third contact area is an area in which the second brush roller and the endless belt come into contact with each other. A fourth contact area is an area in which the second roller and the endless belt come into contact with each other. LN2 is a length of an area in which the third contact area and the fourth contact area overlap with each other.

A controller measures a stop duration time when an intermediate transfer belt and a secondary transfer belt are stopped, and based on a measurement result, rotates and stops the intermediate transfer belt such that the stretched position by stretch rollers of the intermediate transfer belt is changed. At the same time, the controller rotates and stops the secondary transfer belt such that a stretched position by stretch rollers of the secondary transfer belt is changed. A time from starting to stopping the rotation of the intermediate transfer belt and a time from starting to stopping the rotation of the secondary transfer belt are overlapped.

A conveying belt is disposed so as to guide a recording medium on a side opposite to an image carrying belt across an extension line of a stretch surface formed by a transfer nip and a pressure member. Thus, the recording medium delivered from the transfer nip is guided on the side opposite to the image carrying belt across the extension line of the stretch surface. Therefore, even in a case of guiding a recording medium whose bending rigidity is high in particular, it is possible to suppress a rear end of the recording medium to move in a direction of separating from the image carrying belt at upstream of the transfer nip.

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Abiko, Japan

Haruhiko Omata