Canon Kabushiki Kaisha

Satoru Motohashi

Hiroshi Sato

Satoshi Sunahara

Nobuo Oshima

Keiji Okano

Shuhei Tokiwa

Tomonori Mori

Noriyuki Komatsu

Teruhiko Sasaki

Makoto Hayashida

Yuuki Nakamura

Shunsuke Uratani

Yasushi Shimizu

Hiroshi Satoh

Yuji Kawaguchi

Masanobu Saito

Hiroki Tanaka

Takayuki Namiki

Akihisa Matsukawa

Katsuichi Abe

Akira Domon

Gaku Konishi

Norihiro Shirahata

Shinji Katagiri

Shuichi Tetsuno

Tsuguhiro Yoshida

Takayuki Tanaka

Masanori Tanaka

Yosuke Watanabe

Takumi Furukawa

Takahiro Ikeda

Go Shindo

Kuniaki Tamagaki

Tsubasa Yoshida

Provided is an image forming apparatus that can execute a first operation to move developer from a surface of a charging member to a surface of an image bearing member, and a second operation to supply developer to a cleaning portion, wherein a region of the surface of the image bearing member to which the developer is supplied in the second operation includes a region where a second potential difference is generated, so that an electrostatic force is generated to move the developer, which is charged to the normal charging polarity in the first operation immediately before supplying the developer, from the charging member and the image bearing member.

Image forming apparatus

An image forming apparatus includes a control portion to execute a first operation in which a charging voltage applying portion generates a first potential difference that generates an electrostatic force to move developer from a charging member to an image bearing member, a second operation in which a developing voltage applying portion generates a second potential difference that generates an electrostatic force to move developer from the image bearing member to a developer bearing member, and a third operation in which a transfer voltage having a polarity corresponding to the normal charging polarity of the developer by the transfer voltage applying portion is applied while the developer passes through a transfer portion where the developer is transferred to a developer member. A region on a surface of the image bearing member where the second potential difference is generated in the second operation includes a region where the first potential difference is generated in the first operation.

Image forming apparatus having longer term anti-fogging

A developing device in an apparatus main body of an image forming device includes a developing container having an accommodation chamber to accommodate a developer and a developing chamber communicating with the accommodation chamber through a communication port, with the accommodation chamber and developing chamber being integrally formed such that the developing chamber is disposed below the accommodation chamber in a state where the developing device is in use in the apparatus main body. The developer container includes an abutting surface which forms the accommodation chamber and abuts a second end portion of a sheet opposite to a first end portion such that the sheet is maintained in a bent state until the second end portion of the sheet passes in front of an upstream end of the communication port in a rotation direction of the conveyance member and then reaches a light guide provided in the accommodation chamber.

Developing device

An image forming apparatus includes a brush member that includes a fiber yarn and that can come into contact with a surface of an image bearing member at a downstream of a transfer member and at an upstream of a charging member in a rotation direction of the image bearing member. The image bearing member and the brush member are relatively movable to a first position at which a leading end of the fiber yarn separates from the surface of the image bearing member, and a second position at which the leading end of the fiber yarn comes into contact with the surface of the image bearing member. A relative approaching direction of the brush member to the image bearing member upon relative movement from the first position to the second position is a direction from a downstream side to an upstream side in the rotation direction.

Image forming apparatus including movable brush member

A foreign substance collection apparatus includes: a frame body; a photosensitive drum; a cleaning roller which collects foreign substances from a surface of the photosensitive drum; a collecting roller which further collects the foreign substances having been collected by the cleaning roller from the cleaning roller; and a scraping member which scrapes off the foreign substances from the collecting roller. A foreign substance collecting portion included in the frame body has, in a posture during use: a first inner bottom surface which is positioned below the scraping member in a gravity direction; an outer bottom surface which is positioned further below the first inner bottom surface; and a connecting surface which intersects the first inner bottom surface and the outer bottom surface and which connects the first inner bottom surface and the outer bottom surface with each other.

Foreign substance collection apparatus, process cartridge, and image forming apparatus

An image forming apparatus includes a first image forming portion, a second image forming portion, a belt, a charging voltage applying portion, and a transfer voltage applying portion. With respect to a movement direction of a recording material, the first image forming portion is provided upstream of the second image forming portion. In an image forming operation, a potential difference between a first transfer voltage and a potential at a first transfer portion, which is formed on a first image bearing member and does not form the image, is greater than a potential difference between a second transfer voltage and a potential at a second transfer portion, which is formed on a second image bearing member and does not form an image.

Image forming apparatus with image bearing members having different surface layer thicknesses

Image forming apparatus capable of suppressing image defect due to foreign matter

An image forming apparatus includes a latent image forming portion configured to form a latent image on an image bearing member; a developing device including a container configured to store toner and a developing member configured to supply the toner to the latent image formed on the image bearing member to form a toner image; an environment sensor configured to detect environmental information related to an environment in which the developing device is placed; and a controller configured to control switching between a first mode and a second mode, in which a number of prints per unit time is less than that in the first mode. The controller is configured to perform switching from the first mode to the second mode based on an update value obtained by adding or subtracting over time an index value weighted in accordance with the environmental information detected by the environment sensor.

An image forming apparatus includes an image bearing member, a developer container, a developing portion, a replenishment port configured to allow replenishment of one-component developer from a replenishment container, a conveyance portion configured to convey the developer accepted for replenishment through the replenishment port toward the developing portion, a developer remainder amount detection portion whose output value changes on a basis of an amount of developer accommodated in the developer container. A controller changes a developer conveyance speed of the conveyance portion in a conveyance operation on a basis of the output value of the developer remainder amount detection portion, the conveyance operation being an operation of conveying developer toward the developing portion by the conveyance portion and is performed before the image forming operation is started.

Image forming apparatus having developer conveyance speed control

A charge roller includes, in a surface thereof, recesses that have sizes that are equivalent to or larger than a volume average particle diameter of a toner accommodated in a developing unit and that are capable of collecting the toner retransferred to a photosensitive drum.

There is demand to reduce the amount of developing agent fed to a cleaning member. The amount of developing agent that is fed to the cleaning member is decided based on the amount of developing agent recovered by the cleaning member or the amount of use of a process cartridge.

An image forming apparatus includes a cartridge having an image bearing member and a developer bearing member that bears a developer, and a detection unit configured to detect if the cartridge is new. A lubricant of a polarity opposite to a polarity of the developer is coated on the developer bearing member, and if the cartridge is detected to be new, prior to start of an image forming operation, a discharging operation of discharging the lubricant from a surface of the developer bearing member onto the image bearing member is performed. When a predetermined time elapses from a start of the discharging operation and before an end of the discharging operation, a potential difference between a surface potential of the image bearing member and a surface potential of the developer bearing member is set smaller than when the discharging operation is started.

Image forming apparatus having a lubricant and developer of opposite polarity

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Kashiwa, Japan

Satoru Motohashi