Canon Kabushiki Kaisha

Yusaku Iwasawa

Tomoaki Nakai

Hiroyuki Sakakibara

Yasuharu Hirado

Yasuhiro Shimura

Koji Nihonyanagi

Hisashi Nakahara

Satoru Taniguchi

Taisuke Minagawa

Bunro Noguchi

Takamitsu Soda

Hideaki Yonekubo

Nozomu Nakajima

Yuji Fujiwara

Masaki Shimomura

Yu Izaki

Hiroyuki Seki

Takaaki Tsuruya

Yuichiro Hirata

Takayoshi Kihara

Yasutaka Yagi

Takateru Ohkubo

Masaki Hirose

Hirohiko Aiba

Ken Yokoyama

Taku Watanabe

Hiroki Eguchi

Masatake Usui

A fixing member includes a conductive layer that generates heat when a circulation current in a circumferential direction of the fixing member having a tubular shape is induced. The conductive layer includes segments arranged in a row in a longitudinal direction of the tubular shape and electrically separated from each other. Each segment is formed continuously over an entire circumference of the tubular shape in the circumferential direction. The conductive layer is configured such that a heat generation amount in an end portion of the fixing member in the longitudinal direction is less than a heat generation amount in a central portion of the fixing member in the longitudinal direction when an alternating magnetic field is applied to a whole area of the fixing member in the longitudinal direction in a state where a temperature of the central portion is equal to a temperature of the end portion.

Fixing member and fixing unit

A controller of an image forming apparatus controls a transfer voltage applying portion so that a voltage is not applied to a transfer member or a voltage of an opposite polarity to a normal charge polarity of toner is applied to the transfer member, in a first period including at least a period, after rotation of a photosensitive member and a developing member, from first arrival of a first region at a transfer portion to first arrival of a second region at the transfer portion, and so that at least a first voltage of the same polarity as the normal charge polarity and a second voltage of the same polarity as the first voltage and larger in absolute value than the first voltage are applied to the transfer member in a second period after the first period and before a toner image reaches the transfer portion.

Image forming apparatus with control of transfer voltage

An image forming apparatus includes a rotatable photosensitive member, a charging member, a developing member, a transfer member, a voltage applying portion, and a controller. The controller is capable of changing a trailing end voltage to a first trailing end voltage lower than a transfer voltage applied to the transfer member by the voltage applying portion when a toner image is transferred from the photosensitive member to a recording material and to a second trailing end voltage higher than the first trailing end voltage. In an image forming operation after rotation of the photosensitive member is stopped in a state in which the image forming operation is not completed, the controller carries out control so that the second trailing end voltage is applied when a trailing end of the recording material with respect to a feeding direction passes through a transfer portion.

Image forming apparatus that selectively changes trailing end voltage

An image forming apparatus includes a photosensitive member, a charging member, a charging power source, a developing member, a transfer member, a transfer power source, an acquiring portion, and a controller. The controller controls a charging voltage to be a first charging voltage when an electric resistance value of the transfer member is a first resistance value and to be a second charging voltage not less than the first charging voltage in absolute value when the electric resistance value is a second resistance value lower than the first resistance value, and so that a change amount of the charging voltage when the electric resistance value is changed from the second resistance value to a third resistance value lower than the second resistance value is greater than a change amount of the charging voltage when the electric resistance value is changed from the first resistance value to the second resistance value.

Image forming apparatus

An image forming apparatus includes image bearing members, an intermediary transfer member having ion conductivity, primary transfer members, a first voltage applying portion, a secondary transfer member, a second voltage applying portion, and a controller. On the basis of image information, the controller controls a transfer voltage applied to the secondary transfer member so as to be different between a first voltage when a first region, in which a coverage indicating a ratio occupied by an image region per predetermined area is a first coverage passes through the secondary transfer portion and a second voltage when a second region, in which the coverage is a second coverage larger than the first coverage, passes through the secondary transfer portion. The controller controls a change amount of the first voltage with respect to the second voltage so as to be different between a first mode and a second mode.

Image forming apparatus capable of suppressing maldistribution of an ion conductive agent on an intermediary transfer member

An image forming apparatus including a holding apparatus configured to collect residual developer remaining on an intermediate transfer belt and temporarily hold the residual developer, and a cleaning member configured to remove toner borne on the photosensitive drum that moves the toner held by the holding apparatus to the intermediate transfer belt and discharging the toner. Toner from a development roller is supplied to the cleaning member before toner reversely transferred from the intermediate transfer belt is supplied to the cleaning member.

Image forming apparatus for an intermediate transfer of a toner image and for reversely transferring collected developer to an image bearing member

An image forming apparatus includes an intermediate transfer member that contacts an image bearing member to form a primary transfer portion, contacts a secondary transfer member to form a secondary transfer portion, and contacts a charging member that can receive a voltage from a charging power source, to form a charging portion. A toner image borne on the image bearing member is primarily transferred to the intermediate transfer member and secondarily transferred to a transfer material. If toner remains on the intermediate transfer member, the charging member electrically charges the remaining toner. If driving of the intermediate transfer member causes toner to drop onto the intermediate transfer member from the charging member, The timing at which to start image formation is controlled to prevent the dropped toner from moving to a transfer material conveyed to the secondary transfer portion.

The image forming apparatus includes an image bearing member, a charge member, a transfer unit, an application unit, a cleaning member, a detection unit that detects an index value, and a control unit that, in a case where one or a plurality of consecutive toner images for which the index value is equal to or greater than a first threshold value is formed, performs control which increases an absolute value of the transfer voltage for a toner image to be formed next, and in a case where one or a plurality of consecutive toner images for which the index value is less than a second threshold value equal to or greater than the first threshold value is formed, performs control which decreases an absolute value of the transfer voltage for a toner image to be formed next.

Image forming apparatus having a control of transfer voltage

An image forming apparatus includes an image bearing member on which an electrostatic latent image is formed; an image bearing member charging unit which applies an image bearing member charging voltage; a developer bearing member to which developing voltage for developing the electrostatic latent image on the image bearing member is applied and which bears and transports a developer; a primary transfer unit which transfers a developer image on the image bearing member to an intermediate transfer member; and a charging member which charges the developer on the intermediate transfer member. The developer image is first primarily transferred and then secondarily transferred to a recording material. The image forming apparatus operates in a first mode in which a residual developer on the intermediate transfer member after the secondary transfer is electrostatically removed from the intermediate transfer member, and a second mode.

The image forming apparatus includes a control unit that executes a supply operation to supply a toner charged with a regular charge polarity, to at least one abutting portion of a plurality of abutting portions, at the time of image non-formation, the plurality of abutting portions being formed by a plurality of cleaning members and a plurality of image bearing members, the control unit determining an image bearing member to which the most amount of the toner charged with the regular charge polarity is supplied, based on image formation information, the image formation information being information about an image formation executed before the supply operation is executed.

An image-forming apparatus includes a charging unit that charges toner with polarity opposite to a normal charging polarity of the toner and a control unit that performs collection operation for the toner charged with the opposite polarity by the charging unit. The control unit causes a first power supply to apply a first voltage having the opposite polarity to a first transfer member while first and second image bearing members are in contact with an intermediate transfer member. The control unit causes the first power supply to apply a second voltage having the opposite polarity and higher in absolute value than the first voltage to the first transfer member while the first image bearing member is in contact with the intermediate transfer member and the second image bearing member is separated from the intermediate transfer member.

Image-forming apparatus

When executing a job which is a series operations for forming images on a single or a plurality of transfer materials and outputting the transfer material(s), started by a start instruction, a control device switches a polarity of a voltage applied by a first transfer power source in response to a switching of a polarity of a voltage applied by a charging power source, and switches a voltage applied by a second transfer power source from a first voltage to a second voltage which is larger in absolute value than the first voltage.

The image forming apparatus includes a charge power source and a controller. The charge power source is configured to switch a voltage with the same polarity as an original charging polarity of a toner and a voltage with a polarity opposite to the original charging polarity of the toner and apply the voltages to a charge device. The controller executes a control of switching a polarity of a voltage to be applied from the charge power source to the charge device from the opposite polarity to the same polarity before termination of secondary transfer of all of toner images in a job, and moving both a residual toner charged to the opposite polarity through application of the voltage with the opposite polarity and a residual toner charged to the same polarity through application of the voltage with the same polarity to an image bearing member.

An image forming apparatus charges toner on a transfer belt by using a first brush and collects the toner, in which a second brush is provided on the upstream side of the first brush, and the amount of inroad of the second brush into the transfer belt is larger than the amount of inroad of the first brush into the transfer belt.

An image forming apparatus includes: a transfer member that secondarily transfers a developer image primarily transferred to a intermediate transfer medium, to a recording medium; a charging member that charges residual developer remaining on the intermediate transfer medium after the developer image is secondarily transferred from the intermediate transfer medium to the recording medium; and a storage portion that stores information on a image bearing member. A bias applied to the charging member is changed based on the information when the residual developer charged by the charging member is collected by being transferred from the intermediate transfer medium to the image bearing member.

Growing community of inventors

Mishima, Japan

Yusaku Iwasawa