公开(公告)号：US11150574B2

公开(公告)日：2021-10-19

申请号：US17178577

申请日：2021-02-18

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Kazunori Tanaka ,  Kanako Morimoto ,  Shiro Kaneko

IPC: G03G15/00 ,  G03G15/06

Abstract: An image forming apparatus includes a plurality of image forming units, a developing voltage power supply, a current detection unit, and a control unit. The image forming units form an image by superimposing a toner image of a same color and a same type, and substantially same development conditions are set to evenly divide an image density among the image forming units. The control unit detects whether there is an anomaly in the image forming unit based on detecting a DC component of developing current, being either of current flowing through a non-exposed portion of an image carrier during image formation, and current flowing through an exposed portion of the image carrier. When an anomaly is detected in any image forming unit, the control unit inhibits use of the image forming unit, and resets the development conditions to evenly divide an image density among the usable image forming units.

公开(公告)号：US11067923B2

公开(公告)日：2021-07-20

申请号：US16984788

申请日：2020-08-04

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Takahiro Okubo ,  Mitsuhiro Hashimoto ,  Kazuhiro Nakachi ,  Shiro Kaneko

IPC: G03G15/16 ,  G03G15/20 ,  G03G15/00

Abstract: An image forming apparatus includes an image forming portion, a high-voltage generation circuit, a current detection portion and a control portion. The image forming portion includes an image carrying member, a charging device, an exposure device and a developing device which includes a developer carrying member for carrying a two-component developer. The control portion can perform a transfer memory prediction mode that includes a step of estimating, when a first reference image is formed, the level of occurrence of transfer memory based on the direct-current component of a development current flowing through the developer carrying member and a step of measuring, when the measured direct-current component of the development current is larger than a predetermined value, the amount of charge of the toner within the developing device and estimating the cause of occurrence of the transfer memory based on the measured amount of charge of the toner.

公开(公告)号：US10691052B2

公开(公告)日：2020-06-23

申请号：US16554448

申请日：2019-08-28

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Akifumi Yamaguchi ,  Yasuhiro Tauchi ,  Kenichi Tamaki ,  Koji Suenami

IPC: G03G15/00

Abstract: In the first charge amount acquisition operation, based on density of a plurality of toner images for measurement or based on a direct component of a developing current at the time of forming the plurality of toner images in addition to the density of the plurality of toner images for measurement, the charge amount acquisition section acquires a first toner charge amount that is a charge amount of toner included in the toner image for measurement. In the second charge amount acquisition operation, based on the toner density detected at the time of image formation and a relationship between the first toner charge amount and the toner density detected in the first charge amount acquisition operation, the charge amount acquisition section acquires a second toner charge amount that is a charge amount of the toner in the development device.

公开(公告)号：US20190369523A1

公开(公告)日：2019-12-05

申请号：US16424674

申请日：2019-05-29

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Akifumi Yamaguchi ,  Yasuhiro Tauchi ,  Eiji Gyotoku ,  Yu Sasaki

IPC: G03G15/06

Abstract: An image forming apparatus includes a developer information acquisition unit. The developer information acquisition unit performs a developer deterioration information acquisition operation. In the developer deterioration information acquisition operation, the developer information acquisition unit acquires a tilt of a measurement straight line representing the relationship between the change amount of the frequency in a first measurement toner image forming operation and the density change amount of the measurement toner image based on the change amount of the frequency in the first measurement toner image forming operation and a result of detecting density of the measurement toner image in a density detecting unit, and acquires a toner charging amount based on the acquired tilt of the measurement straight line and the reference information in the storage unit so as to acquire information relating to deterioration of developer based on the acquired toner charging amount.

公开(公告)号：US10222726B2

公开(公告)日：2019-03-05

申请号：US15851371

申请日：2017-12-21

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu

IPC: G03G15/09 ,  G03G15/08

Abstract: A developing device includes a development roller, a layer-thickness limiting member, and a first screw. The development roller includes a fixed magnet and a sleeve. The first screw supplies developer to the development roller while conveying the developer in a first conveyance direction. The sleeve includes a plurality of recesses. Each of the recesses has an elongated shape, and a downstream end and an upstream end in the first conveyance direction. The downstream end is located farther downstream in a rotational direction of the sleeve than the upstream end. When the developer in each of the recesses passes the layer-thickness limiting member, the developer moves upstream in the first conveyance direction.

公开(公告)号：US09857732B2

公开(公告)日：2018-01-02

申请号：US15456965

申请日：2017-03-13

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Kenichi Tamaki

IPC: G03G15/08 ,  G03G15/09

CPC classification number: G03G15/0889 ,  G03G15/0808 ,  G03G15/0812 ,  G03G15/0907 ,  G03G15/0921

Abstract: A developing device includes a developing roller and a conveyor roller. The developing roller includes a first magnet. The conveyor roller includes a second magnet. The first magnet includes a first magnetic pole and a second magnetic pole. The second magnet includes a third magnetic pole and a fourth magnetic pole. The first and fourth magnetic poles are magnetic poles having the same polarity. One of the second and third magnetic poles is a magnetic pole having the same polarity as the first magnetic pole. The other of the second and third magnetic poles is a magnetic pole having a polarity different from the first magnetic pole. The developer is transferred from the conveyor roller to the developing roller by the third and second magnetic poles. The developer is transferred from the developing roller to the conveyor roller by the first and fourth magnetic poles.

公开(公告)号：US20170299977A1

公开(公告)日：2017-10-19

申请号：US15480473

申请日：2017-04-06

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu ,  Yasuhiro Tauchi

IPC: G03G15/08 ,  G03G15/09

CPC classification number: G03G15/0812 ,  G03G15/0889 ,  G03G15/0893 ,  G03G15/0921 ,  G03G15/0928

Abstract: A developing device includes a housing, a developing roller, a developer stirring member, and a layer thickness regulating member. The developing roller includes a stationary magnet and a sleeve. The stationary magnet includes a first magnetic pole having a specific polarity, and a second magnetic pole lying downstream of the first magnetic pole and having the same polarity as the first magnetic pole. In an entire inter-pole region between the first magnetic pole and the second magnetic pole, the stationary magnet produces a magnetic force including a horizontal component that keeps the specific polarity and has a value greater than zero (mT). The inter-pole region includes a flat area where a horizontal magnetic force component having a minimum absolute value exits and the horizontal magnetic force component changes within a range of 0.5 (mT) or less, the flat area extending over a range of 10 degrees or more.

公开(公告)号：US20170269510A1

公开(公告)日：2017-09-21

申请号：US15457063

申请日：2017-03-13

Applicant: KYOCERA Document Solutions Inc.

Inventor： Kenichi Tamaki ,  Tamotsu Shimizu ,  Akifumi Yamaguchi

IPC: G03G15/09

CPC classification number: G03G15/0889 ,  G03G15/0812 ,  G03G15/0907 ,  G03G15/0921

Abstract: A developing device includes a developing roller, a conveyor roller and a developer stirring unit. The developing roller is arranged to face a photoconductive drum at a predetermined developing position. The developing roller includes a fixed first magnet and a first sleeve. The conveyor roller is arranged to face the developing roller at a predetermined facing position. The conveyor roller includes a fixed second magnet and a second sleeve. The developer stirring unit stirs the developer and supplies the developer to the conveyor roller. The first magnet includes a first magnetic pole composed of a predetermined magnetic pole and a second magnetic pole arranged downstream of and adjacent to the first magnetic pole and having the same polarity as the first magnetic pole. The developer is transferred from the developing roller to the conveyor roller after passing through a repulsive magnetic field formed by the first and second magnetic poles.

公开(公告)号：US09690229B2

公开(公告)日：2017-06-27

申请号：US15239650

申请日：2016-08-17

Applicant: KYOCERA Document Solutions Inc.

Inventor： Tamotsu Shimizu

IPC: G03G15/08

CPC classification number: G03G15/0812 ,  G03G15/0806

Abstract: An image forming apparatus includes a rotator, a driving control portion, and a layer thickness control portion. The rotator conveys toner to contact position to an image carrying member, and supplies toner to the image carrying member at the contact position. The driving control portion controls rotation of the rotator so as to rotate the rotator during a developing period, and stop the rotation of the rotator after a set time has elapsed since an end of the developing period. The layer thickness control portion causes the rotator to carry toner by controlling a potential difference between a potential of the rotator and a predetermined potential so that toner on the rotator at the contact position has a first layer thickness during the developing period and has a second layer thickness while the rotation of the rotator is stopped, the second layer thickness being thicker than the first layer thickness.

公开(公告)号：US09541856B2

公开(公告)日：2017-01-10

申请号：US14642062

申请日：2015-03-09

Applicant: KYOCERA Document Solutions Inc.

Inventor： Shizuka Ikazaki ,  Akihiro Watanabe ,  Tamotsu Shimizu

IPC: G03G15/06 ,  G03G15/08

CPC classification number: G03G15/065 ,  G03G15/0803

Abstract: An image forming apparatus includes an image carrier, a developer carrier, a bias applying section, a leakage detecting section, and a bias controlling section. The developer carrier carries developer in the form of a layer of magnetized filaments to supply toner to the image carrier. The bias applying section applies to the developer carrier a development bias including a direct current voltage VmagDC and an alternating current voltage VmagAC superposed on each other. The leakage detecting section causes a discharge between the image carrier and the developer carrier and detects a leakage voltage when the discharge occurs. The leakage detecting section performs the leakage voltage detection in a blank region of the image carrier bearing no electrostatic latent image. The bias controlling section determines an alternating current voltage VmagAC according to a detected leakage voltage, and a frequency of the alternating current voltage VmagAC according to the voltage VmagAC.

Abstract translation: 图像形成装置包括图像载体，显影剂载体，偏压施加部，泄漏检测部和偏置控制部。 显影剂载体以一层磁化细丝的形式携带显影剂，以向图像载体提供调色剂。 偏置施加部分对显影剂载体施加包括彼此重叠的直流电压VmagDC和交流电压VmagAC的显影偏压。 泄漏检测部分在图像载体和显影剂载体之间引起放电，并且在放电发生时检测泄漏电压。 泄漏检测部在不具有静电潜像的图像载体的空白区域中执行泄漏电压检测。 偏置控制部根据检测到的泄漏电压和交流电压VmagAC的频率根据电压VmagAC来决定交流电压VmagAC。