Canon Kabushiki Kaisha

Kengo Sato

Takashi Ueno

Motohiro Ogura

Shozo Aiba

Masaki Kakitani

Kenji Aoki

Daigo Matsuura

Yoshiro Tsukada

Tadashi Iwakawa

An image forming apparatus includes a first roller pair including a first roller and a second roller, a first driving unit, a second roller pair, a second driving unit, an image forming unit, and a control unit configured to execute a first mode and a second mode. The second mode includes (1) a first processing, (2) a second processing, and (3) a third processing of controlling the first driving unit such that the rotational speed of the first roller pair becomes faster than the second rotational speed. The first mode includes (1) a fourth processing, (2) a fifth processing, and (3) a sixth processing of controlling the first driving unit such that the rotational speed of the first roller pair is decelerated from the first rotational speed to equal to or less than the second rotational speed.

Image forming apparatus

An image forming apparatus includes an image bearing member, a transfer portion, first and second correcting portions including first and second roller pairs and first and second detectors, respectively. The first and second correcting portions correct a sheet position in a widthwise direction. A controller, in a case the sheet is fed to the transfer portion via the first correcting portion from the second correcting portion, causes the first correcting portion to correct the sheet position to a first position to be aligned with the image transferred in the transfer position and causes the second correcting portion to correct the sheet position to a second position. When the sheet has been moved to a reference position by the second roller pair, the second position is a position offset from the reference position toward an opposite side to a direction where the sheet position detected by the first detector is shifted from the first position.

Image forming apparatus with two correcting portions that correct a position of a sheet in the width direction

An image forming apparatus includes an image forming unit, a fixing unit including a first rotary member and a second rotary member, a reciprocation mechanism configured to reciprocally move the fixing unit in a width direction, a duplex conveyance unit configured to reverse a recording material of which a toner image is fixed on a first surface and reconvey the recording material to the image forming unit in a double-sided image formation in which toner images are formed and fixed on the first surface and second surfaces of the recording material, and a control unit configured to control the reciprocation mechanism not to move the fixing unit in the width direction while the fixing unit is nipping and conveying the recording material at a fixing nip portion for fixing the toner image on the first surface of the recording material in the double-sided image formation.

Provided is an image forming apparatus, in which a recording material is conveyed by a reverse portion rotated in a first direction at a first velocity which is faster than a conveyance velocity of the recording material in a fixing portion after a rear end portion of the recording material passes through the fixing portion, and then, the recording material is conveyed to a conveying portion by the reverse portion rotated in a second direction opposite to the first direction through a conveyance path at a second velocity which is faster than the conveyance velocity of the recording material in the fixing portion, and a conveyance velocity of the recording material is set to a third velocity which is slower than the second velocity at a predetermined timing before the rear end portion of the recording material reaches a curved portion of the conveyance path.

An image forming apparatus includes an image forming unit configured to form an image on a sheet; a second reading sensor, and a controller. The first reading sensor is provided on a conveyance path, and is configured to read a first surface of the sheet conveyed along the conveyance path. The second reading sensor is provided at a position different from a position of the first reading sensor, and is configured to read a second surface which is on a side opposite to the first surface of the sheet conveyed along the conveyance path. The controller is configured to control the image forming unit to form measurement images for measurement of printing positions on the sheet, control the first reading sensor to read end portions of the sheet, and to control the second reading sensor to read the end portions of the sheet.

Image forming apparatus including first and second sensors reading different surfaces at different positions to detect posture and shape of a sheet

A sheet conveying apparatus includes: a first pair of conveying rollers for conveying a sheet; a second pair of conveying rollers against which the leading edge of the sheet conveyed by the first pair of conveying rollers is hit and which conveys the sheet together with the first pair of conveying rollers by rotating after a loop is formed on the sheet; a separating portion for separating the first pair of conveying rollers; a first conveyance path for guiding the sheet; a second conveyance path which is a path different from the first conveyance path and guides the sheet; and a controller which changes a separation timing at which the first pair of conveying rollers is separated after the loop is formed on the sheet, depending on whether the sheet is guided by the first conveyance path or by the second conveyance path.

Sheet conveying apparatus and image forming apparatus

An image forming apparatus includes a rotatable image drum for carrying a toner image; a transfer member contacted to the drum to transfer the toner image from the drum onto a transfer member; a cleaning blade provided downstream of the transfer member with respect to a peripheral moving direction of the drum and having a free end portion contacted to the drum, the blade being configured to remove, with rotation of the drum, toner remaining on the drum after transfer of the toner image by the transfer member; and a toner retaining member cooperative with the drum to provide a toner accommodation space toner removed from the drum by the blade. The toner retaining member can retain a part of the toner accommodated in the toner accommodation space and capable of being deformed by the toner accommodated in the accommodation space to discharge the toner from the accommodation space.

Image forming apparatus with cleaning blade

A sheet conveyance apparatus is equipped with a first rotator, a second rotator conveying a sheet together with the first rotator, a cam member changing a position of the second rotator with respect to the first rotator, a drive unit rotating the cam member, and a load portion applying load on a rotation of the cam member. The load portion includes a contact member having a cam surface formed on a side surface in an axial direction of the cam member, an abutment member capable of abutting against the cam surface, and a biasing member biasing one of the contact member and the abutment member toward the other, a biasing force of the biasing member converted into a force, applying load to the rotating cam member, by the cam surface opposing to a rotating direction in which the cam member is driven by the drive unit.

Sheet conveyance apparatus and image forming apparatus

A sheet conveying apparatus is provided with a driving portion, and the driving portion is normally rotated, driving power from the driving portion is transmitted to a cam member through a transmitting portion. Then, one of a rotary roller pair is moved to another one. The sheet conveying apparatus further includes a restricting portion that restricts the cam member from turning in a direction opposite to a turning direction turned in response to a normal rotation of the driving portion.

An image forming apparatus is capable of executing, in non-image formation, for example, in a sheet-to-sheet interval, a developer bearing member stop mode in which the developer conveyance by a development sleeve is stopped. For example, the apparatus turns off primary transfer bias in the sheet-to-sheet interval. Even if fogging toner is no longer supplied after the development sleeve drive is stopped, the apparatus can reduce frictional force variation between the photosensitive drum and the intermediate transfer belt to prevent speed variation of the photosensitive drum or the intermediate transfer belt, thus reducing the possibility of image unevenness and out of color registration.

A color image forming apparatus includes a first temperature detection unit configured to detect a temperature of an exposure device, a second temperature detection unit configured to detect a temperature of a photosensitive member, a color registration pattern detection unit configured to detect a color registration pattern formed on a transfer member, an actual-measurement-based color registration adjustment value calculation unit configured to calculate an actual-measurement-based color registration adjustment value from a result of the detection of the color registration pattern detection unit, and a prediction-based color registration adjustment value calculation unit configured to calculate a prediction-based color registration adjustment value from the temperature of the exposure device detected by the first temperature detection unit and the temperature of the photosensitive member detected by the second temperature detection unit.

An image forming apparatus includes: a rotatable image bearing member; a toner image forming portion; a transfer member; a cleaning blade, provided downstream of the transfer member and upstream of the toner image forming portion with respect to a rotational direction of the image bearing member; a discharging member, provided downstream of the cleaning blade and upstream of the toner image forming portion with respect to the rotational direction; and a thin plate-like member provided downstream of the discharging member and upstream of the toner image forming portion with respect to the rotational direction. An end of the thin plate-like member is contacted to a surface of the image bearing member toward an upstream side with respect to the rotational direction.

An image forming apparatus includes an image bearing member, an exposure device including a plurality of light emitting elements, and a holding member configured to hold the exposure device at a mounting portion between first positioning members provided at both longitudinal end portions of the exposure device. In addition, a second positioning member positions the holding member relative to the image bearing member so as to position the exposure device relative to the image bearing member at the mounting portion, a second elastic member urges the holding member toward the image bearing member so as to maintain a positioned state of the second positioning member, and first and second adjusting members adjusts a distance in a direction of an optical axis between the image bearing member and the exposure device at both longitudinal end portions and at the mounting portion of the exposure device. The holding member has a rigidity necessary to curve the exposure device in the longitudinal direction when the second adjusting member adjusts a distance in the direction of the optical axis between the image bearing member and the exposure device at the mounting portion of the exposure device.

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Koshigaya, Japan

Kengo Sato