Kyocera Document Solutions Inc.

Shimano Inc.

Koji Uno

Keisuke Oba

Yasuhiro Michishita

Masaru Watanabe

Ryuichiro Takamoto

Takuji Watanabe

Yuta Kitabayashi

Yasuaki Sakamoto

Satoshi Uemura

Ayato Morikami

Yuki Nakaiwa

Kanako Kikuchi

Kazuhiro Fujii

Tadashi Ichida

Yoshihiro Yamagishi

Haruyuki Takebayashi

Kenichi Kasama

Tetsuya Toichi

Nobuyuki Hayashi

Masafumi Hashimura

Tamotsu Shimizu

Akifumi Yamaguchi

An image forming apparatus includes a plurality of image carriers, a charging device, an exposure device, a development device, and an intermediate transfer belt. The image carrier has a surface on which an amorphous silicon photosensitive layer is formed. The intermediate transfer belt is a plastic belt having a surface resistivity of 9.5 to 10.5 (log Ω/square). An offset amount of the primary transfer roller from the image carrier is 0 to 2 (mm), a contact surface pressure between the image carrier and the intermediate transfer belt is 0.5 to 1.5 (gf/mm), and a charge density of primary transfer current that flows when the primary transfer voltage is applied to the primary transfer roller is 0.016 to 0.040 (μC/cm).

Image forming apparatus

The intermediate transfer unit includes: an endless intermediate transfer belt which is turned around while carrying a toner image on its outer circumferential surface; and a plurality of rollers on which the intermediate transfer belt is turnably stretched, wherein the intermediate transfer belt has, on its inner circumferential surface, an information recording area in which belt information has been recorded, and the intermediate transfer belt has a mark at a position in the outer circumferential surface where a positional relationship between the mark and the information recording area comes to a specified relationship.

Intermediate transfer unit and image forming apparatus

An image forming apparatus includes a plurality of image forming portions, an intermediate transfer belt, a primary transfer member, a secondary transfer roller, a counter roller, and a charge eliminating device. The counter roller is pressed against the secondary transfer roller via an intermediate transfer belt to thereby form a secondary transfer nip portion. The charge eliminating device includes a charge eliminating needle that is disposed with an end part thereof pointing to a downstream side in a conveyance direction of the recording medium, and that is grounded, and a charge eliminating needle protection cover that has a guide surface that is opposed to the recording medium having passed through the secondary transfer nip portion, and that maintains a constant interval between the recording medium and the charge eliminating needle, and eliminates residual charge on the recording medium having passed through the secondary transfer nip portion.

Image forming apparatus with charge eliminating needle protection cover that maintains constant interval between the needle and a sheet

An image forming apparatus includes a plurality of image forming portions, an intermediate transfer belt, a primary transfer member, a secondary transfer roller, a counter roller, and a charge eliminating device. The counter roller is pressed against the secondary transfer roller via an intermediate transfer belt to thereby form a secondary transfer nip portion. The charge eliminating device includes a charge eliminating needle that is disposed with an end part thereof pointing to a downstream side in a conveyance direction of the recording medium, and that is grounded, and a charge eliminating needle protection cover that has a guide surface that is opposed to the recording medium having passed through the secondary transfer nip portion. The guide surface is formed of a conductive material having a resistance value of 10Ω or lower, and is in a floating state.

An image forming apparatus includes an image carrying member, an intermediate transfer belt, a primary transfer roller, a first belt support roller, a secondary transfer roller, a second belt support roller, a current feeder, a controller, a current sensor, and a rectifier. The current sensor has a lead member. The rectifier shuts off a current passing from the second belt support roller to the ground if the voltage on the second belt support roller is less than a predetermined reference voltage. The controller controls the output current such that the secondary transfer current has a current value resulting from subtracting a leak current from the output current and, when the lead member is in a conducting state, keeps the voltage on the second belt support roller less than the reference voltage.

An image forming apparatus includes an image carrying member, an intermediate transfer belt, a primary transfer roller, a first belt support roller, a secondary transfer roller, a second belt support roller, a current output portion, a current sensing portion, and a control portion. The current output portion passes across the secondary transfer roller a secondary transfer current as part of an output current. The current output portion and the second belt support roller are electrically connected together. The current sensing portion senses a leakage current passing from the first belt support roller via the intermediate transfer belt to the second belt support roller. The control portion sets the output current such that the secondary transfer current has a value given by subtracting a leakage current from the output current and keeps the voltage on the second belt support roller between −50 V and 50 V, inclusive.

A processor causes a printing portion to execute, when first conveying processing is executed, test print processing for executing processing of forming a plurality of test toner images on a sheet under a print condition that differs for each of the plurality of test toner images. The processor acquires a plurality of first sensing densities when the first conveying processing is executed. The processor causes the printing portion to execute the test print processing when second conveying processing is executed. The processor acquires a plurality of second sensing densities when the second conveying processing is executed. The processor compares the plurality of first sensing densities and the plurality of second sensing densities to adjust the print condition in the print processing when the second conveying processing is executed.

Adjustment method for image forming apparatus, and image forming apparatus

An image forming apparatus includes a developing current detecting portion, a control portion, and a deviation detecting portion. The developing current detecting portion detects a developing current that flows between a developing device and a photoconductor drum during development of an electrostatic latent image. The control portion causes the exposure device to form electrostatic latent images of at least two patch images at different positions from each other and at different timings from each other in a main scanning direction. The deviation detecting portion detects deviation of one of the exposure device and the photoconductor drum with respect to the other based on a detection timing at which the developing current is detected during development of the electrostatic latent images of the at least two patch images.

Image forming apparatus capable of detecting deviation between exposure device and photoconductor drum

An image forming apparatus includes a transfer processing portion, a detection processing portion, a correction processing portion, and an adjustment processing portion. The transfer processing portion transfers a detection toner image to outside an output area of a transfer object to which a toner image as an output target is transferred from an image-carrying member. The detection processing portion detects a density of the detection toner image that has been transferred to the transfer object by the transfer processing portion. The correction processing portion corrects a detection result of the detection processing portion based on an amount of toner transferred from the image-carrying member to the output area at a transfer timing when the detection toner image is transferred. The adjustment processing portion adjusts an image forming condition based on the detection result after correction by the correction processing portion.

Image forming apparatus capable of adjusting image forming condition accurately, and image forming condition adjustment method

An image forming apparatus has an image forming portion, a fixing device, a temperature sensing device, and a control portion. The fixing device has a fixing member having a heated rotary member and a pressing member forming a fixing nip by making contact with the heated rotary member. The temperature sensing device senses the surface temperature of at least one of the heated rotary member and the pressing member in a plurality of regions in the axial direction. The control portion estimates the thickness distribution of the surface layer of at least one of the heated rotary member and the pressing member in the axial direction based on the time taken for the surface temperature in the plurality of regions to reach the predetermined temperature, and thereby estimates the lifetime of at least one of the heated rotary member or the pressing member based on the estimated thickness distribution.

An image forming apparatus has a photosensitive member, a charging member, an exposing device, a developing device, a transfer member, a polishing member, a driving device, a voltage applying device, a torque detector, and a control portion. The photosensitive member has a photosensitive layer and a surface protection layer formed on the surface of the photosensitive layer. The polishing member has an elastic layer on its circumferential surface, and rotates with a linear velocity difference from that of the photosensitive member. The torque detector detects the torque of the driving device. The control portion estimates an attachment condition of discharge products to the surface of the photosensitive member based on the torque of the driving device detected by the torque detector. When the torque is equal to or higher than a predetermined value, the control portion performs an image degradation suppression process.

Image forming apparatus provided with a photosensitive member having a photosensitive layer and a surface protection layer which is formed on the surface of the photosensitive layer and which has a hardness higher than that of the photosensitive layer

An image forming apparatus includes an image carrier, a cleaning member, a rotation controlling part, a first obtaining part and a mode changing part. The image carrier has a surface to carry a toner image transferred onto a sheet. The cleaning member contacts the surface of the image carrier at a downstream side in a rotating direction of the image carrier from a transferring position transferring the toner image to collect a toner from the image carrier and to hold the toner. The rotation controlling part has a first speed control mode rotating the cleaning member at a first rotational speed and a second speed control mode rotating the cleaning member at a second rotational speed faster than the first rotational speed and switches from the first speed control mode to the second speed control mode at predetermined switch timing.

Image forming apparatus having a cleaning member that controls rotation speed according to sheet thickness and number of sheets

An image forming apparatus includes an image forming unit, an intermediate transfer belt, a brush roller, a drive mechanism, a contact control mechanism, and an operation control unit. The image forming unit includes a photoconductor drum, and forms a toner image on an outer circumferential surface of the photoconductor drum. The operation control unit is configured to perform a cleaning mode including cleaning the brush roller while an image forming operation is not being performed, cause the contact control mechanism to set the photoconductor drum and the intermediate transfer belt to the non-contact phase in the cleaning mode, and cause the drive mechanism, in the non-contact phase, to drive the brush roller to rotate at a rotation speed higher than a rotation speed of the brush roller in the image forming operation, and drive the intermediate transfer belt.

An image forming apparatus () includes an image forming section (), an intermediate transfer belt (), a drive roller (A), a secondary transfer roller (), a brush section (), a cleaning device (), a power supply device (), and a ground portion (). The brush section () is disposed at a location downstream of the secondary transfer roller () in a direction of travel of the intermediate transfer belt () and facing the drive roller (A) with the intermediate transfer belt () in between. A potential difference is applied between the brush section () and the secondary transfer roller () by the power supply device () and the ground portion (), so that an electric current having the same polarity as a normal charge polarity flows from the brush section () through the drive roller (A) to the secondary transfer roller ().

Image forming apparatus having cleaning section for removing residual toner on intermediate transfer belt

An image forming apparatus includes: a photosensitive drum; a transfer belt configured to be charged to an opposite polarity to the surface of the photosensitive drum to electrostatically attract a recording paper sheet and convey the sheet while pressing the sheet against the photosensitive drum, thereby transferring a toner image formed on the surface of the photosensitive drum to the sheet; a fixing section configured to apply heat to the recording paper sheet having the toner image transferred thereto and thus fix the toner image on the sheet; a toner collecting member disposed to face a separating position where the recording paper sheet is separated from the transfer belt and extending in a width direction of the sheet being conveyed, the toner collecting member being electrically grounded; and a thermally conductive member configured to collect heat near the fixing section and conduct the collected heat to the toner collecting member.

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Osaka, Japan

Koji Uno