Canon Kabushiki Kaisha

Shinichi Agata

Kohei Matsuda

Shinya Yamamoto

Tetsuya Kobayashi

Masato Koyanagi

Yoshihiro Mitsui

Kodai Hayashi

Kosuke Ikada

Takuya Oka

Keitaro Nakata

Kentaro Kawata

Hisashi Taniguchi

Kentaro Yamawaki

Takayoshi Kihara

Shuhei Kawasaki

Kentarou Kawata

Yuji Kawaguchi

Masanori Tanaka

Motoki Adachi

Yuichiro Hirata

Masahito Kato

Bunro Noguchi

Go Shindo

Shinichi Hagiwara

Takashi Mukai

Hideo Kihara

Taku Watanabe

Yasukazu Ikami

Issei Imamura

Yuji Moriki

Hisashi Yamauchi

Keisuke Endoh

Akinobu Saito

Takuto Kobayashi

An image forming apparatus includes an image bearing member, a developer bearing member, a drive unit for driving the image bearing member and the developer bearing member in varied peripheral speeds, a control unit, a developing voltage application unit, a supply member for supplying a developer to the developer bearing member, and a supply member voltage application unit. The control unit executes a first image forming mode in which a rotational peripheral speed ratio between surface movement speeds of the developer bearing member and the image bearing member is not greater than 1 and a second image forming mode in which the rotational peripheral speed ratio is greater than 1, and the control unit controls the drive unit so that a difference between developing voltage and supply voltage is greater in the second image forming mode than that in the first image forming mode.

Image forming apparatus

An image forming apparatus includes a rotatable image bearing member, a charging member, a developing member, a cleaning member, an accommodating portion, and a controller capable of executing an image forming operation and a supplying operation for supplying a metal soap, accommodated in the accommodating portion, onto a surface of the image bearing member by the developing member. The controller carries out control so that when the supplying operation is executed, a surface moving speed of the image bearing member is higher than a surface moving speed of the image bearing member when the image forming operation is executed.

Image forming apparatus controlling image forming and supply operations

An image forming apparatus comprising: an image bearing member, a developing member that forms a toner image with a toner including a metal soap having a polarity opposite to that of the toner, a supply member that supplies the toner to the developing member, and a control unit that executes a metal soap supply operation of supplying the metal soap from the developing member to the image bearing member when an operation other than the image forming operation is executed, wherein the metal soap supply operation includes a first mode and a second mode, and a potential difference between the supply member and the developing member, which causes an electrostatic force in the direction from the supply member to the developing member to act on the metal soap, is smaller in the metal soap supply operation in the second mode than in the first mode.

Image forming apparatus with developing member that supplies toner to surface of image bearing member to form toner image

An image forming apparatus includes a detection member configured to detect a conveyance state of a recording medium, a control unit configured to sequentially execute a first operation for continuously executing a rotation operation of an image bearing member and an intermediate transfer member without stopping them when the detection member detects a failure, and a second operation for stopping the rotation operation of the image bearing member when the surface of the image bearing member is moved by a predetermined distance through the rotation operation of the image bearing member after the failure is detected.

An image forming apparatus that executes an image forming operation for forming a toner image on a recording material and an application operation of applying a metal soap to a surface of an image bearing member by supplying a toner stored in a toner storing unit to the surface of the image bearing member from the developing member. A surficial moving speed of the image bearing member during the application operation is lower than the surficial moving speed of the image bearing member during the image forming operation, and a speed difference between the surficial moving speed of the developing member and the surficial moving speed of the image bearing member during the application operation is larger than that during the image forming operation.

Image forming apparatus that suppresses occurrence of image smearing by maintaining a metal soap on a surface of a photoconductor

A charging memberthat charges an image bearing memberhas an electrically conductive support and an elastic layer in contact with the image bearing member. The elastic layer includes a semi-conductive rubber composition having a matrix-domain structure including a matrix and domains having electric conductivity. The matrix has a higher volume resistivity than the domain. The developer includes a toner having toner particles. The toner particles each have a surface layer including an organosilicon polymer. The organosilicon polymer has a structure represented by R&#x2014;SiO(R is a hydrocarbon group having at least 1 and not more than 6 carbon atoms). The adhesion ratio of the organosilicon polymer on the surface of the toner particle is 90% or more.

Process cartridge and image forming apparatus

A developing device includes a developer carrying member, a developing frame, and a regulating member. The regulating member includes a curved surface portion contactable to a surface of the developer carrying member, and satisfies the following relationships: 200 MPa&#x2264;HM&#x2264;1100 MPa, and 0.08 mm&#x2264;Rb&#x2264;0.3 mm, where HM is a Martens hardness of toner contained in the developer under a maximum load of 2.0&#xd7;10N, and Rb is a radius of curvature of the curved surface portion.

Developing device, process cartridge and image forming apparatus

Provided is an image forming apparatus, including an apparatus main body, an image bearing member unit having at least an image bearing member and a charging member, and a developing unit having at least a developer bearing member. The apparatus main body has a controller, the image bearing member unit further has a first storage unit that stores first correction information corresponding to life information of the developing unit, the developing unit further has a second storage unit that stores second correction information corresponding to life information of the developing unit, and the controller acquires the first correction information and the second correction information, uses the acquired first correction information and the acquired second correction information to correct a charging bias to be applied to the charging member, and applies the corrected charging bias to the charging member.

Image forming apparatus mountable with image bearing member unit and developer bearing member

An image forming apparatus includes a control unit that controls an electric potential difference between a development roller and a supply roller in such a manner that force in a direction from the supply roller toward the development roller acts on toner in a section of an image forming region extending from a leading edge of a first image forming region toward a trailing edge thereof. The control unit controls the electric potential difference in such a manner that force acting on the toner becomes smaller in a section extending from a switching point, which is located at a position obtained by returning from a leading edge of a second image forming region to the first image forming region by a distance equal to or greater than a circumferential length of the development roller, to the trailing edge of the first image forming region.

A developing device includes developer, a developer bearing member, and a supply member that is in contact with the developer bearing member and supplies the developer. The developing device further includes a developing chamber in which the developer bearing member and the supply member are disposed, a developer containing chamber that contains the developer, a partition wall that partitions the developing chamber and the developer containing chamber from each other and is provided with an opening that communicates the developing chamber and the developer containing chamber with each other, and a conveyance member that conveys the developer from the developer containing chamber to the developing chamber. The conveyance member is provided with a hole through which the developer can pass or has a protrusion that generates a gap between the conveyance member and the partition wall.

Developing device, process cartridge, and image forming apparatus

A developing blade has a protrusion that protrudes toward a developing roller in an opposing portion facing the developing roller. The potential difference between a supply bias and a developing bias is denoted by &#x394;(V), a contact pressure of the developing blade with respect to the developing roller is denoted by X (gf/cm), a height of the protrusion from the opposing surface that faces the developing roller at a position further toward a tip side than the protrusion is denoted by H (mm), and a length of the opposing surface in the rotation direction of the developing roller is denoted by L (mm). When viewing a cross-section perpendicular to the rotation axis of the developing roller, 0.05&#x2264;H&#x2264;0.1, 0.15&#x2264;L&#x2264;1.0, and 15&#x2264;X&#x2264;60 are established, and at least &#x394;&#x2265;&#x2212;5*X&#x2212;125 is satisfied.

Developing device having developer regulating member, process cartridge, and image forming apparatus

An image forming apparatus includes: a first exposing unit exposing a surface of a charged photosensitive member to form a latent image; a second exposing unit exposing the surface of the photosensitive member after the surface of the photosensitive member passes a transfer position at which a toner image obtained by causing toner to adhere to the latent image is transferred to a transferred body and before the surface of the photosensitive member reaches a charging position; and a control unit varying a length of a period from a timing at which a portion of the photosensitive member exposed by the second exposing unit is initially charged by the charging member to a timing at which the first exposing unit starts formation of the latent image when performing image formation based on a print signal, based on information related to a photosensitive layer thickness of the photosensitive member.

Image forming apparatus for preventing abnormally discharged image

An image forming apparatus includes an acquiring portion that acquires a duration of an overcharged state occurring in an area of an image bearing body charged by a charging member after the image bearing body is exposed by a preliminary exposing portion. Adjustment is made to an interval between a first timing when the preliminary exposing portion starts exposing the image bearing body before execution of an adjustment operation for setting a transfer voltage value and a second timing when a voltage applying portion starts, during the subsequent adjustment operation, applying a voltage with an adjustment voltage value to a transfer member such that the second timing is later than a third timing when the duration acquired by the acquiring portion ends.

Image forming apparatus acquiring a duration of overcharge

An image forming apparatus includes a developing device, a detection mode execution unit, and a notice signal generating unit. The developing device supplies a toner bearing member with toner in a container by rotating a toner supply member in a contact manner with the toner bearing member. The detection mode execution unit executes a detection mode in which a predetermined period for changing a toner amount in the foam layer by rotating the toner supply member is provided, a capacitance Cbetween the first and second electrode members is detected before the predetermined period, and a capacitance Cbetween the first and second electrode members is detected after the predetermined period. The notice signal generating unit generates a low toner amount notice signal in response to an absolute value |C&#x2212;C| of a difference between the capacitances Cand Cbeing smaller than a predetermined threshold.

An image forming apparatus includes a rotatable image bearing member on which an electrostatic latent image is formed; a charging member for being supplied with a charging voltage which is a DC voltage not having an AC voltage component and for contacting the bearing member to electrically charge a surface of the bearing member using an electric discharge; a transfer member for transferring onto a transfer material a toner image formed on the surface of the bearing member by developing the electrostatic latent image, at a transfer position; wherein the charging potential of the charging member is different between when the charging member provides a first region with a potential and when the charging member provides a second region with a potential, thus providing a predetermined potential difference between the first region and the second region, and wherein the transfer member is not supplied with a voltage when the second region is at the transfer position, where the first region is a region on the image bearing member which has been charged by the charging member and which is to be an image forming region, and the second region is a region of the image bearing member which is a non-image-forming region in an immediately previous rotation of the image bearing member and which corresponds to the first region on the bearing member.

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Suntou-gun, Japan

Shinichi Agata