Canon Kabushiki Kaisha

Yuichi Tanabe

Keita Shigihara

Yuki Kurosu

Shin Hasegawa

Takahiro Kobayashi

Hisashi Tsukijima

Kentaro Yamana

Daiki Takahashi

Shinya Kitago

Disclosed is an image forming apparatus including a detachable unit having a rotator with a driven shaft coupling and a drive unit having a drive shaft coupling to engage with the driven shaft coupling and providing a force to the rotator via the drive shaft coupling. The driven shaft coupling includes spiral first and second receiving surfaces. The drive side shaft coupling includes a spiral first transmitting surface, which contacts the first receiving surface and provides a rotational force in a first rotational direction to the driven shaft coupling, and a spiral second transmitting surface, which contacts the second receiving surface and provides a force in the second rotational direction opposite to the first rotational direction to the driven shaft coupling when the drive shaft coupling rotates in the second rotating direction. The second transmitting and receiving surfaces are rougher than the first transmitting and receiving surfaces.

Image forming apparatus including particularly arranged driving mechanism

An image forming apparatus includes a support frame, a driving device including a first supporting portion configured to hold the drive source on a first surface and configured to rotatably support the drive gear on a second surface, and a second supporting portion configured to support the drive gear with the first supporting portion, a board holding member disposed in a manner overlapping the first supporting portion in a rotational axis direction of the drive gear, and a third supporting portion disposed between the first supporting portion and the board holding member in the rotational axis direction, and configured to support the board holding member, one end of the third supporting portion being fixed to a side of the first surface of the first supporting portion by a first fastening member, another end of the third supporting portion being fixed to the board holding member by a second fastening member.

Image forming apparatus and method for producing drive unit

An Oldham coupling having play in a rotational direction and being capable of transmitting a driving force. The Oldham coupling includes a developing drive gear as a first hub, a drive coupling as a second hub, and an intermediate member that transmits a driving force between the developing drive gear and the drive coupling. The developing drive gear includes a protruded portion that is fitted to a recessed portion of the intermediate member to transmit a driving force between the developing drive gear and the intermediate member. When seen in a rotational axis direction of the Oldham coupling, the shape of a protruded portion is a substantially rhombic shape.

Oldham coupling and image forming apparatus

An image forming apparatus includes a driving unit including a driving source, a drive gear, a first support member that holds the driving source and includes a first support portion that supports one end portion of a rotation shaft of the drive gear, and a second support member that includes a second support portion that supports another end portion of the rotating shaft. The first support member includes a fastening hole disposed in a projection plane obtained by projecting the second support portion in the rotation axis direction of the drive gear. The second support member is disposed upstream of the first support member in a fastening direction, and includes a mounting portion extending so as to be in contact with the first support portion in the projection plane, the mounting portion including an attachment hole, the attachment hole being disposed at a position overlapping the fastening hole.

Image forming apparatus

An image forming apparatus is capable of suppressing deterioration in accuracy of control for switching a motor from forward to reverse rotation in a configuration in which a coupling having play in a rotation direction is interposed in a drive train between the motor and a driven member. The image forming apparatus includes a motor that rotationally drives a photosensitive drum and a developing sleeve; a coupling interposed in a drive train between the motor and the developing sleeve and/or a drive train between the motor and the photosensitive drum and having play in a rotation direction; and a CPU that controls the motor. The CPU rotates the motor forward at a speed Vat the time of image formation, stops the motor after the end of the image formation, rotates the motor forward at a speed Vlower than the speed V, and then reversely rotates the motor.

Image forming apparatus capable of suppressing deterioration in accuracy of controlling switching of motors from forward rotation to reverse rotation

An image forming apparatus includes an image forming unit configured to form an image; a holding portion configured to hold the image forming unit; a supporting portion configured to support the holding portion; a fastening portion configured to fasten the holding portion and the supporting portion to each other; and an arcuate slit portion provided in at least one of the holding portion and the supporting portion and extending substantially about the fastening portion in a range at least not less than 180&#xb0; and less than 360&#xb0; around the fastening portion.

An image forming apparatus includes a control portion that controls a drive speed of a first drive source, so that a speed of a sheet conveyed in a conveyance nip portion is greater than a speed of the sheet conveyed in a transfer nip portion, and a drive speed of a second drive source, so that the speed of the sheet conveyed in the transfer nip portion is greater than a speed of the sheet conveyed in a fixing nip portion. The control portion changes a rotation speed of a pair of conveyance members from a first speed to a second speed greater than the first speed after a first loop amount of the sheet formed between the transfer nip portion and the fixing nip portion becomes greater than a second loop amount of the sheet formed between the transfer nip portion and the conveyance nip portion.

Image forming apparatus having a control portion capable of controlling a rotation speed of a pair of conveyance members

An image forming apparatus includes a sensor and a shutter to cover a window for the sensor. The shutter includes a detection hole to uncover the window and a cover portion to cover it. In an opening position of the shutter, the window and the hole are opposed to each other, and in a closing position of the shutter, the window and the cover portion are opposed to each other. A holder for the sensor includes a side wall opposed to a side of the sensor remote from a sheet feeding path and extended in a widthwise direction. As viewed in a horizontal direction perpendicular to the belt, the side wall is provided with a first area overlapping the hole in the closing position and a second area overlapping the window in the closing position. The first area is below the shutter and lower than the second area.

A belt conveyance apparatus includes an endless belt conveyed while being supported by a plurality of support rollers in a tensioned state. The plurality of support rollers include a tension roller and a steering roller. The tension roller, which is disposed adjacent to and downstream of the steering roller in a conveyance direction of the endless belt, has a reverse crown shape in which end portions in a rotational axis direction each have an outer diameter larger than a middle portion.

Belt conveyance apparatus and image forming apparatus for reduced belt buckling

An image forming apparatus includes a main assembly; a door member which supports one of roller members constituting a feeding nip for a recording material and which is rotatable about an axis parallel with said roller members in a sidewise direction of said main assembly to open said feeding nip; a pair of urging mechanisms which are provided at opposite end portions of said door member with respect to a front-rear direction of said main assembly and which fix said door member to said main assembly so as to be capable of opening and closing said door member, said urging mechanism urging said door member toward said main assembly in a state that said door member is closed; and an operating member provided with a grip for manual opening of said door member, said grip being disposed in a position nearer to a front side than a center portion position of said door member with respect to the front-rear direction, and said operating member being rotatably supported in a position nearer to a rear side than a center position between urging mechanisms.

Growing community of inventors

Kashiwa, Japan

Yuichi Tanabe