Kyocera Mita Corporation

Kyocera Document Solutions Inc.

Mita Industrial Co., Ltd.

Hiroyuki Hamakawa

Asami Kotera

Hiroshi Yamazaki

Akihiro Watanabe

Masashi Fujishima

Koji Suenami

Yoshihiro Yamagishi

Hirohisa Endou

Sayo Uemura

Eiji Nimura

Hiroyuki Hazama

Takashi Terada

Takaaki Kamei

Takahiko Murata

Masanobu Maeshima

Masaru Watanabe

Kenichi Tamaki

Nariaki Tanaka

Ikuo Makie

Sueaki Okamoto

Yukihiro Aikawa

Takashi Nagashima

Shingo Mori

Hiroshi Kageyama

Yoshiaki Tabata

Toshinobu Katafuchi

Hirotsugu Ogawa

Seitaro Yoshida

Kiyoaki Miyamoto

Sayo Mabuchi

Kunio Nakai

Kenichi Ashida

Nobuhiro Nakajima

Shinji Ogaki

Masaru Gotoh

A developing device includes a developing container, a first stirring and conveying member, a second stirring and conveying member, a developer replenishing port, a developer discharging portion, a developing roller, a toner supply roller, a regulating blade, a toner receiver member, and a vibration generating device. The developing device is capable of executing a toner collecting mode in which the vibration generating device vibrates the toner receiver member so that toner deposited on the toner receiver member is shaken off by vibration and is collected into the second conveying chamber, in the non-image formation period. The developing device is capable of executing a forced discharge mode in which developer containing the collected toner collected from the toner receiver member into the second conveying chamber is forcibly discharged from the developer discharging portion to outside of the developing container, after the toner collecting mode is executed.

Developing device and image forming apparatus including same

An image forming apparatus includes a developer storage portion, a developing roller, a magnetic force generating portion, and an image carrying member. The magnetic force generating portion is provided in the developing roller and generates a magnetic force for keeping the developer on an outer circumferential surface of the developing roller. The image carrying member is disposed to face the developing roller across a predetermined developing gap, is rotationally driven, receives the toner from the developer supplied to the developing gap by the developing roller, and keeps a toner image on an outer circumferential surface of the image carrying member. The image forming apparatus, during non image formation, supplies a more amount of developer to the developing gap than an amount of developer for developing supplied to the developing gap during image formation such that the outer circumferential surface of the image carrying member is cleaned.

Image forming apparatus

A developer replenishing apparatus includes a developer housing container and a sensor. The developer housing container includes a container main body having a wall that partitions an internal space, a shaft section arranged so as to extend in a first direction in the internal space, a moving wall which moves from an upstream side to a downstream side in the first direction along the shaft section and which conveys the developer, and a developer discharge port which is arranged near a downstream end in the first direction of the container main body. The sensor is arranged at a position that enables the sensor to generate different outputs between before and after the moving wall reaches a prescribed position on a movement route. The determining unit determines a state where there is no developer in the developer housing container when the sensor generates an output determined in advance.

Developer replenishing apparatus including container having moving wall

An image forming apparatus has a developing device and a controller. The developing device includes a stirring member, rotatable at a first speed or at a second speed lower than the first speed, which varies, according to its speed, the amount of developer discharged out of the developing device. The controller drives the stirring member to rotate at the second speed, then switches the rotation speed of the stirring member to a third speed higher than the second speed but lower than the first speed, and then drives the stirring member to rotate at the third speed for a first period. The third speed is set higher the lower the fluidity of the developer.

A longitudinal end portion of an opposing magnetic member of a developer supporting rotator is positioned more longitudinally outside than a longitudinal end portion of a toner supporting side magnetic member. With respect to the opposing magnetic member facing the toner supporting side magnetic member and a downstream magnetic member disposed more downstream than the opposing magnetic member in a rotational direction, a magnetic force generated in a vicinity of both longitudinally end portions thereof is greater than a magnetic force generated longitudinally inside thereof. A housing includes a sealing portion that projects from a position facing a face at a longitudinal end portion of the developer supporting rotator toward the face, such that the sealing portion prevents the toner in a space between the face and an inner face of the housing from scattering outside.

Developing device and image forming apparatus

Provided is a developing device including: a developing container including a developer replenishing port from which the developer is replenished, and a developer discharge port which is provided on a downstream side of one of the conveyance paths and from which surplus developer is discharged; and a discharge regulating portion provided to one of the plurality of stirring members which is arranged in the one of the conveyance paths, in which the discharge regulating portion includes a regulating member arranged so as to face the developer discharge port, for regulating movement of the developer to the developer discharge port side, and a decelerating conveyance member arranged between the helical blade and the regulating member, for partially reducing a conveying speed of the developer in the one of the conveyance paths.

Developing device and image forming apparatus provided therewith

A developing unit includes a developing roller which rotates about a rotational axis to supply toner to a photoreceptor, and a magnetic roller which forms a magnetic brush with a two-component developing agent having carrier and the toner and thereby forms a toner layer on the developing roller, the developing roller including: a cylindrical core portion which includes an electric conductor; a first resistive layer which covers a cylindrical surface of the core portion; a second resistive layer which covers the first resistive layer, and has electric-resistivity lower than that of the first resistive layer; and a current leakage control member which prevents leakage of electric current from the core portion toward the second resistive layer through an end of the developing roller along a direction of the rotational axis.

Developing unit and image forming device

The surface of a developing roller is coated with a phenol resin layer at a higher level in triboelectric series than a toner. A positively charged toner supplied from a magnetic roller onto the developing roller is negatively charged by friction with the phenol resin layer at the higher level in the triboelectric series. As a result, the positive charge of the toner is cancelled out, and the charge amount of toner per unit weight on the developing roller (Q/M)s decreases. Applying this principle, relationship between (Q/M)s and the charge amount of toner per unit weight on the magnetic roller (Q/M)m satisfies (Q/M)s&#x3c;(Q/M)m.

Developing device forming toner layer by magnetic brush and image forming apparatus using same

A developing device is provided with a developing roller arranged to face a photoconductor for forming an electrostatic latent image and adapted to supply a toner to the photoconductor, an agitating member for agitating a developer, a supply roller that holds the developer agitated by the agitating member, and supplies the toner to an area facing the developing roller; a restricting member for blocking the developer supplied onto the supply roller and restricting the amount of the developer conveyed by the supply roller, and an intermediate roller including a first magnetic pole facing in a direction toward the staying developer by being restricted by the restricting member for attracting the staying developer and arranged at such a position as to face the developer blocked by the restricting member. Thus, the developing device can avoid image quality deterioration even when a developing process continues over a long period of time.

Developing device and image forming apparatus with intermediate roller for assuring efficient circulation of developer

Embodiments relate to a developing device for use in an image-forming apparatus including a developing roller having a conductive base surface which may be covered with a resin layer containing an ion conductive material and a silicone-modified urethane resin having an ether structure. The resin layer may be a product of a crosslinking reaction of the silicone-modified urethane resin and the ion conductive material in the presence of a crosslinking agent and a crosslinking catalyst.

Developing device and image-forming apparatus

A developing unit includes a developing roller which rotates about a rotational axis to supply toner to a photoreceptor, the developing roller including: a cylindrical core portion which includes an electric conductor; a first resistive layer which covers a cylindrical surface of the core portion; a second resistive layer which covers the first resistive layer, and has electric-resistivity lower than that of the first resistive layer; and a current leakage control member which prevents leakage of electric current from the core portion toward the second resistive layer through an end of the developing roller along a direction of the rotational axis.

A developing device is provided for visualizing an electrostatic latent image previously formed on the surface of an image carrier as a toner image. The developing device has a developing roller placed at a position facing the image carrier, carrying a toner on the surface thereof, conveying the toner and flying the conveyed toner onto the surface of the image carrier; and a resin layer coated on the surface of the developing roller. The absolute value of the difference in charge between the toners in the upper and lower layers of the toner layer formed on the developing roller as the toner carried on the developing roller is 6 &#x3bc;C/g or less.

A developing device includes a container for containing toner, a rotatable shaft provided in the container, a spiral shaped blade formed on an outer circumference of the shaft, and a first spiral member for conveying the toner in the longitudinal direction of the shaft by means of rotation. In addition, a toner removing member is provided for removing the toner attached to the first spiral member. Then, by rotation of the first spiral member, the toner removing member is moved in the longitudinal direction of the shaft and the direction that is orthogonal to the longitudinal direction of the shaft so as to be in contact with the surface of the first spiral member. Accordingly, it is possible to adequately scrape the toner off the spiral shaped blade and the shaft, thereby effectively prevent an aggregation of toner from occurring.

Toner conveying device, developing device, and image forming device having the same

A control partrotates a developer rollerat a second rotation speed, which is slower than a normal rotation speed during an image formation period (first rotation speed), during a non-image formation period while a heateris in use. This prevents deformation of the developer rollercaused by radiant heat from a photoconductive drumeffectively prevents the appearance of image fogging, concentration unevenness, and the like, and also suppresses toner deterioration in a development unit

Image forming apparatus comprising a developer roller

A developing device () includes a developing sleeve () for supplying toner particles (T) to a latent image area () on a peripheral surface of a photoconductive drum () while rotating about a central shaft (). The developing sleeve () has an immovable sleeve magnet () therein. Two magnetic members () are disposed in opposite end portions of the developing sleeve () and are spaced a predetermined distance from the peripheral surface of the developing sleeve. Each magnet member () has an arc shape. A magnetic member magnet () is mounted in the magnet member () and faces a sleeve magnet () so that opposite facing portions of the magnetic member magnet () and the sleeve magnet () have the same polarity. With this construction, toner particles are prevented from leaking from the end portions of the developing sleeve ().

Growing community of inventors

Osaka, Japan

Hiroyuki Hamakawa