JP2002214911A - Developing device - Google Patents

Developing device

Info

Publication number
JP2002214911A
JP2002214911A JP2001005146A JP2001005146A JP2002214911A JP 2002214911 A JP2002214911 A JP 2002214911A JP 2001005146 A JP2001005146 A JP 2001005146A JP 2001005146 A JP2001005146 A JP 2001005146A JP 2002214911 A JP2002214911 A JP 2002214911A
Authority
JP
Japan
Prior art keywords
developer
toner
developing sleeve
developing device
developing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2001005146A
Other languages
Japanese (ja)
Inventor
Junichi Terai
純一 寺井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP2001005146A priority Critical patent/JP2002214911A/en
Publication of JP2002214911A publication Critical patent/JP2002214911A/en
Pending legal-status Critical Current

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  • Magnetic Brush Developing In Electrophotography (AREA)
  • Dry Development In Electrophotography (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a developing device provided with the conventional simplicity and low cost, where stored quantity of the developer can be increased, the service life of developer is long and toner filming is prevented. SOLUTION: A second developing sleeve 4b which is a second developer carrier is provided. Furthermore, differing magnetic poles are installed in the upstream and downstream sides of the proximal position between a first developing sleeve 4a and the second developing sleeve 4b to be faced to each other. Moreover, the potential of the first developing sleeve 4a and the potential of the second developing sleeve 4b are made the same.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、複写機、ファクシ
ミリ、プリンター等の画像形成装置に適用できる現像装
置に係わり、詳しくは、トナーと磁性キャリアとからな
る二成分現像剤を貯留する現像剤収容室と、内部に磁石
を備え、現像剤収容室にある現像剤を磁力により保持
し、回動により現像剤を搬送する現像剤担持体と、トナ
ーを収容するトナー収容室とを有し、現像剤の移動によ
り現像剤に接触するように貯留されているトナーを取り
込む現像装置に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device applicable to an image forming apparatus such as a copying machine, a facsimile, a printer, and the like. More specifically, the present invention relates to a developing device for storing a two-component developer composed of a toner and a magnetic carrier. A developer carrier having a magnet therein, a developer holding body that holds the developer in the developer housing chamber by magnetic force and conveys the developer by rotation, and a toner housing chamber that houses toner. The present invention relates to a developing device that takes in toner stored so as to come into contact with a developer by moving a developer.

【0002】[0002]

【従来の技術】従来、トナー濃度検知手段を必要とせ
ず、現像剤の動きによってトナーを取り込む方式の現像
装置が知られている。しかし、この従来の方式では、現
像剤の動きが活発な箇所とそうでない箇所、あるいは現
像剤の多い箇所と少ない箇所においてトナーの取り込み
量が異なり、部分的にトナー濃度が不安定となって画像
濃度ムラや地汚れが発生しやすい。そこで、トナーホッ
パ内に2つのトナー供給部材を配設し、各トナー供給部
材で形成される経路に現像剤を通過させることにより、
装置長手方向における濃度ムラや地汚れを解決する技術
が特開昭63−4282号公報に開示されている。
2. Description of the Related Art Hitherto, there has been known a developing apparatus of a type which does not require a toner density detecting means and takes in toner by movement of a developer. However, in this conventional method, the amount of toner taken in is different between a portion where the developer is active and a portion where the developer is not active, or a portion where the amount of the developer is large and a portion where the amount of the developer is small. Density unevenness and background contamination are likely to occur. Therefore, by disposing two toner supply members in the toner hopper and passing the developer through a path formed by each toner supply member,
Japanese Patent Application Laid-Open No. 63-4282 discloses a technique for solving density unevenness and background contamination in the longitudinal direction of the apparatus.

【0003】[0003]

【発明が解決しようとする課題】しかし、従来の現像装
置においては1本の現像剤担持体である現像スリーブの
周囲のみに現像剤が吸着されており、現像剤の収容量に
は限界があった。現像剤は感光体ドラムや規制部材とし
ての現像ドクタによりストレスを受け、特に現像剤が少
ない場合はそのストレスが増大し、キャリア表面の摩耗
や表面にトナーや第三添加物が固着するフィルミングが
早期に発生しやすく、現像剤の寿命は短いものとなっ
た。
However, in the conventional developing device, the developer is adsorbed only around the developing sleeve which is a single developer carrier, and the amount of developer stored is limited. Was. The developer is stressed by the photoreceptor drum and the developing doctor as a regulating member. Especially when the amount of the developer is small, the stress increases, and the abrasion of the carrier surface and the filming in which the toner and the third additive adhere to the surface are caused. It easily occurred at an early stage, and the life of the developer was short.

【0004】上記問題点に鑑み、本発明では、従来のシ
ンプルさ及び低コストさを備え、現像剤収容量を増加さ
せることができ、現像剤の寿命が長く、トナーフィルミ
ングを防止できる現像装置を提供することを目的とす
る。
[0004] In view of the above problems, the present invention provides a developing device which has the conventional simplicity and low cost, can increase the amount of developer contained, has a long life of the developer, and can prevent toner filming. The purpose is to provide.

【0005】[0005]

【課題を解決するための手段】上記課題を解決するため
に、請求項1の本発明は、内部に磁界発生手段を有し、
トナーと磁性キャリアとを含む二成分現像材を担持して
搬送する第一の現像剤担持体と、現像剤担持体に担持さ
れて搬送される現像剤の量を規制する規制部材と、規制
部材により掻き落とされた現像剤を収容する現像剤収容
部と、現像材収容部に隣接し、現像剤担持体にトナーを
供給するトナー収容部とを備え、第一の現像剤担持体上
の現像剤のトナー濃度の変化により、現像剤とトナーと
の接触状態を変化させて、現像剤担持体上のトナー取り
込み状態を変化させる現像装置において、第二の現像剤
担持体を有することを特徴とする現像蔵置とする。請求
項2の本発明は、請求項1に記載の現像装置において、
2つの現像剤担持体の最近接位置上下流側のそれぞれ対
向する部位に異なる磁極を配置することを特徴とする現
像装置とする。請求項3の本発明は、請求項1に記載の
現像装置において、2つの現像体担持体の電位を同一に
することを特徴とする現像装置とする。
In order to solve the above problems, the present invention according to claim 1 has a magnetic field generating means inside,
A first developer carrier that carries and transports a two-component developer including a toner and a magnetic carrier; a regulating member that regulates the amount of developer carried and transported by the developer carrier; and a regulating member. A developer accommodating portion for accommodating the developer scraped off by the first developer carrier, and a toner accommodating portion adjacent to the developer accommodating portion for supplying toner to the developer carrier. A developing device that changes the contact state between the developer and the toner by changing the toner concentration of the developer, thereby changing the state of taking in the toner on the developer carrier, characterized by having a second developer carrier. Storage. According to a second aspect of the present invention, in the developing device according to the first aspect,
A developing device is characterized in that different magnetic poles are arranged at opposing portions on the upstream and downstream sides of the closest positions of the two developer carriers. According to a third aspect of the present invention, there is provided the developing device according to the first aspect, wherein the potentials of the two developer carrying members are equalized.

【0006】[0006]

【発明の実施の形態】図1は、本発明の実施の形態を採
用した画像形成装置における現像装置の概略構成図であ
る。潜像担持体である感光体ドラム(1)の側方に配設
された現像装置(2)は、支持ケース(3)、現像剤担
持体としての現像スリーブ(4a)、(4b)、現像剤
収容部材(5)、現像剤規制部材としての現像ドクタ
(6a)、(6b)から主に構成されている。
FIG. 1 is a schematic configuration diagram of a developing device in an image forming apparatus employing an embodiment of the present invention. The developing device (2) disposed on the side of the photosensitive drum (1) as a latent image carrier includes a support case (3), developing sleeves (4a) and (4b) as a developer carrier, and a developing device. It mainly comprises a developer container (5) and developing doctors (6a) and (6b) as developer regulating members.

【0007】感光体ドラム(1)側に開口を有する支持
ケース(3)は、内部にトナー(7)を収容するトナー
収容部としてのトナーホッパ(8)を形成している。ト
ナーホッパ(8)の感光体ドラム(1)側寄りには、ト
ナー(7)と磁性粒子であるキャリアとからなる現像剤
(11)を収容する現像剤収容部(5a)を形成する現
像剤収容部材(5)が、支持ケース(3)と一体的また
は別体的に設けられている。また、現像剤収容部材
(5)の下方に位置する支持ケース(3)には対向面
(3b)を有する突出部(3a)が形成されており、現
像剤収容部材(5)の下部と対向面(3b)との間の空
間によって、トナー(7)を供給するためのトナー供給
開口部(9)が形成されている。
A support case (3) having an opening on the photosensitive drum (1) side forms a toner hopper (8) as a toner storage section for storing a toner (7) therein. A developer accommodating part (5a) for accommodating a developer (11) comprising a toner (7) and a carrier as magnetic particles is provided near the photosensitive drum (1) of the toner hopper (8). The member (5) is provided integrally with or separately from the support case (3). Further, a protruding portion (3a) having an opposing surface (3b) is formed in the support case (3) located below the developer accommodating member (5), and is opposed to a lower portion of the developer accommodating member (5). The space between the surface (3b) and the surface (3b) forms a toner supply opening (9) for supplying the toner (7).

【0008】トナーホッパ(8)の内部には、図示しな
い駆動手段によって回動されるトナー供給手段としての
トナーアジテータ(10)が配設されている。トナーア
ジテータ(10)は、トナーホッパ(8)内のトナー
(7)をトナー供給開口部(9)に向けて攪拌しながら
送り出す。また、トナーホッパ(8)の感光体ドラム
(1)と対向する側には、トナーホッパ(8)内のトナ
ー(7)の量が少なくなった時にこれを検知するトナー
エンド検知手段(12)が配設されている。
Inside the toner hopper (8), there is provided a toner agitator (10) as toner supply means which is rotated by a driving means (not shown). The toner agitator (10) sends out the toner (7) in the toner hopper (8) toward the toner supply opening (9) with stirring. On the side of the toner hopper (8) facing the photosensitive drum (1), a toner end detecting means (12) for detecting when the amount of the toner (7) in the toner hopper (8) becomes small is arranged. Has been established.

【0009】感光体ドラム(1)とトナーホッパ(8)
との間の空間には、第一現像スリーブ(4a)及び第二
現像スリーブ(4b)が配設されている。図示しない駆
動手段で図の矢印方向に回転駆動される第一現像スリー
ブ(4a)及び第二現像スリーブ(4b)は、ぞの内部
に現像装置(2)に対して相対位置不変に配設された、
磁界発生手段としての図示しない磁石を有している。
Photosensitive drum (1) and toner hopper (8)
The first developing sleeve (4a) and the second developing sleeve (4b) are disposed in the space between the first developing sleeve (4a) and the second developing sleeve (4b). A first developing sleeve (4a) and a second developing sleeve (4b), which are driven to rotate in a direction indicated by an arrow in the drawing by driving means (not shown), are disposed inside each of the developing devices (2) so as not to change relative to the developing device (2). Was
It has a magnet (not shown) as a magnetic field generating means.

【0010】現像剤収容部材(5)の、支持ケース
(3)側と対向する側には、現像剤の規制手段としての
第一現像ドクタ(6a)が一体的に取り付けられてい
る。第一現像ドクタ(6a)は、その先端と第一現像ス
リーブ(4a)の外周面との間に一定の比較的狭い隙間
を保った状態で配設されている。
A first developer doctor (6a) as a developer regulating means is integrally attached to a side of the developer accommodating member (5) facing the support case (3) side. The first developing doctor (6a) is disposed with a relatively small gap kept between its tip and the outer peripheral surface of the first developing sleeve (4a).

【0011】さらに現像剤収容部材(5)近傍に位置す
る部位には、前段階の規制部材としてのプレドクタ(1
3)がその先端と第一現像スリーブ(4a)の外周面と
の間に一定の比較的狭い隙間を保った状態で配設されて
いる。本発明の実施の形態では、プレドクタ(13)は
現像剤収容部材(5)を延長し、一体に形成している。
また、同様に第二現像スリーブ(4b)近傍にも現像剤
の規制手段である第二現像ドクタ(6b)が配設され、
その先端と第二現像スリーブ(4b)の外周面との間に
一定の比較的狭い隙間を保った状態で配設されている。
Further, a pre-doctor (1) serving as a regulating member in a previous stage is provided at a portion located near the developer accommodating member (5).
3) is disposed with a relatively small gap kept between its tip and the outer peripheral surface of the first developing sleeve (4a). In the embodiment of the present invention, the predoctor (13) extends the developer accommodating member (5) and is integrally formed.
Similarly, a second developing doctor (6b), which is a means for regulating the developer, is disposed near the second developing sleeve (4b).
The second developing sleeve (4b) is provided with a relatively small gap between the tip and the outer peripheral surface of the second developing sleeve (4b).

【0012】現像剤収容部(5a)は、第一現像スリー
ブ(4a)の磁力が及ぶ範囲で現像剤(11)を循環さ
せるに充分な空間を有するように構成されている。な
お、対向面(3b)はトナーホッパ(8)側から第一現
像スリーブ(4a)側に向けて下向きに傾斜するよう所
定の長さにわたって形成されている。上記構成により、
トナーホッパ(8)の内部からトナーアジテータ(1
0)によって送り出されたトナー(7)は、トナー供給
開口部(9)を通って第一現像スリーブ(4a)に担持
された現像剤(11)に供給され、現像剤収容部(5
a)に運ばれる。そして、現像剤収容部(5a)内の現
像剤(11)は、第一現像スリーブ(4a)に担持され
て、第二現像スリーブ(4b)を経由して感光体ドラム
(1)の外周面と対向する位置まで搬送され、トナー
(7)のみが感光体ドラム(1)に形成された静電潜像
と静電的に結合することにより、感光体ドラム(1)上
にトナー像が形成される。現像を終了した現像剤(1
1)は再び第一現像スリーブ(4a)に戻り、必要なだ
けトナー(7)を補給し攪拌して次の現像に備える。
The developer accommodating portion (5a) has a sufficient space for circulating the developer (11) within a range where the magnetic force of the first developing sleeve (4a) can reach. The facing surface (3b) is formed over a predetermined length so as to be inclined downward from the toner hopper (8) side toward the first developing sleeve (4a) side. With the above configuration,
From inside the toner hopper (8), the toner agitator (1)
The toner (7) sent out by (0) is supplied to the developer (11) carried on the first developing sleeve (4a) through the toner supply opening (9), and is supplied to the developer container (5).
transported to a). The developer (11) in the developer accommodating portion (5a) is carried on the first developing sleeve (4a) and passes through the second developing sleeve (4b) to the outer peripheral surface of the photosensitive drum (1). The toner image is formed on the photosensitive drum (1) by being conveyed to a position opposite to the photosensitive drum (1), and only the toner (7) is electrostatically combined with the electrostatic latent image formed on the photosensitive drum (1). Is done. Developer (1)
1) returns to the first developing sleeve (4a) again, replenishes the toner (7) as needed, agitates it, and prepares for the next development.

【0013】ここで,トナー像形成時における現像剤
(11)の挙動を図2に基づいて説明する。第一現像ス
リーブ(4a)及び第二現像スリーブ(4b)は,その
内部に現像装置に対して相対位置不変に配設された磁界
発生手段としての図示しない磁石を有している、と先に
説明したが、磁石はP1,P2,P3,P4の4個の磁
極からなり、それぞれの極性は N,S,N,S(反対
でも可)と交互に配置されている。現像装置(2)にあ
らかじめ磁性キャリアとトナー(7)とを所定の割合で
混合しておいたいわゆるスタート剤をセットし、第一現
像スリーブ(4a)が回転すると、図2に示すように,
現像剤(11)の搬送は第一現像ドクタ(6a)および
プレドクタ(13)の比較的狭い隙間にて規制され第一
現像スリーブ(4a)の表面に磁着されるもの(A)、
現像剤収容部(5a)内に収容され循環するもの
(B)、プレドクタ(13)上流側に滞留するもの
(C)とに分かれる。
Here, the behavior of the developer (11) when forming a toner image will be described with reference to FIG. The first developing sleeve (4a) and the second developing sleeve (4b) have a magnet (not shown) as a magnetic field generating means disposed in the interior thereof at a position relative to the developing device. As described above, the magnet is composed of four magnetic poles P1, P2, P3, and P4, and the respective polarities are alternately arranged as N, S, N, S (the opposite is also possible). A so-called starting agent in which the magnetic carrier and the toner (7) are mixed in a predetermined ratio in advance is set in the developing device (2), and when the first developing sleeve (4a) rotates, as shown in FIG.
The transport of the developer (11) is regulated by a relatively narrow gap between the first developing doctor (6a) and the pre-doctor (13) and is magnetically attached to the surface of the first developing sleeve (4a) (A).
There are two types: a type (B) that is accommodated in the developer accommodating part (5a) and circulates, and a type (C) that stays upstream of the pre-doctor (13).

【0014】次に,トナーホッパ(8)にトナー(7)
がセットされると,トナー供給開口部(9)より第一現
像スリーブ(4a)に担持された現像剤(11)にトナ
ー(7)が供給される。現像剤(11)と新たに供給さ
れたトナー(7)は現像剤収納部(5a)内の循環部
(B)にて撹拌され帯電して均一化される。現像剤(1
1)のトナー(7)の割合(トナー濃度)が上昇するに
従い、現像剤(11)の流動性は低下し、プレドクタ
(13)を通過できる量が減少するため、滞留部(C)
が大きく成長する(C’)。このときの滞留部(C’)
の表面は流動性の低下により動きが無く、トナー(7)
の供給は停止する。感光体状の静電潜像を現像するに従
い、トナー濃度が減少し、現像剤(11)の流動性が上
昇し、滞留部(C’)が小さくなると(C)、再び表面
は活発に動き出し、トナーの供給を再開する。
Next, the toner (7) is added to the toner hopper (8).
Is set, the toner (7) is supplied from the toner supply opening (9) to the developer (11) carried on the first developing sleeve (4a). The developer (11) and the newly supplied toner (7) are stirred and charged in the circulating section (B) in the developer accommodating section (5a) to be uniform. Developer (1
As the ratio (toner density) of the toner (7) in 1) increases, the fluidity of the developer (11) decreases, and the amount of the developer (11) that can pass through the predoctor (13) decreases.
Grows greatly (C ′). Retention part at this time (C ')
Surface has no movement due to the decrease in fluidity, and toner (7)
Supply stops. As the photoreceptor-like electrostatic latent image is developed, the toner concentration decreases, the fluidity of the developer (11) increases, and the stagnant portion (C ′) decreases (C). Then, the supply of the toner is restarted.

【0015】また、第一現像スリーブ(4a)及び第二
現像スリーブ(4b)が対向する部位にはP1(N)と
P4(S)、P2(S)とP3(N)が互いに異極にな
るよう対向され配置されている。これにより第一現像ス
リーブ(4a)から第二現像スリーブ(4b)へ、また
反対に第二現像スリーブ(4b)から第一現像スリーブ
(4a)へ現像剤(11)がスムーズに移行する。この
移行の際、現像剤(11)は自己循環するためトナー濃
度の局部的なムラは低減される。
Further, P1 (N) and P4 (S), and P2 (S) and P3 (N) have opposite polarities at a portion where the first developing sleeve (4a) and the second developing sleeve (4b) face each other. They are arranged so as to face each other. As a result, the developer (11) smoothly moves from the first developing sleeve (4a) to the second developing sleeve (4b) and vice versa from the second developing sleeve (4b) to the first developing sleeve (4a). During this transition, the developer (11) self-circulates, so that local unevenness in toner density is reduced.

【0016】また、感光体状の静電潜像を現像する際、
地汚れを防止するために、現像スリーブには静電潜像の
明部電位と暗部電位の中間の現像バイアスを印加するの
が通例であるが、第一現像スリーブ(4a)及び第二現
像スリーブ(4b)に電位差があるとどちらか片方へト
ナー(7)が移行し、トナー(7)で真っ黒になるトナ
ーフィルミングが発生する。本発明においてはこれを防
止するために図示しない電源にて両者を同電位に保って
いる。
In developing a photoreceptor-like electrostatic latent image,
In order to prevent background contamination, it is customary to apply a developing bias intermediate between a bright portion potential and a dark portion potential of the electrostatic latent image to the developing sleeve, but a first developing sleeve (4a) and a second developing sleeve are applied. If there is a potential difference in (4b), the toner (7) moves to one of them, and toner filming that becomes black with the toner (7) occurs. In the present invention, in order to prevent this, both are kept at the same potential by a power supply (not shown).

【0017】[0017]

【発明の効果】以上説明したように、第二の現像担持体
である第二現像スリーブを有することで、現像剤収容量
を増加させ、現像剤寿命の長い現像蔵置を提供すること
ができる。また、2つの現像剤担持体である第一現像ス
リーブと第二現像スリーブとの最近接位置上下流側のそ
れぞれ対向する部位に異なる磁極を配置したので現像剤
の移行がスムーズに行われ、現像剤は自己循環し、トナ
ーフィルミングが低減可能な現像装置を提供することが
できる。
As described above, by having the second developing sleeve as the second developing carrier, it is possible to increase the amount of stored developer and provide a developer storage having a long life of the developer. In addition, since different magnetic poles are arranged at opposing portions of the first developer sleeve and the second developer sleeve, which are the two developer carriers, on the upstream and downstream sides of the closest position, the developer is smoothly transferred, and The developer self-circulates, and a developing device capable of reducing toner filming can be provided.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の実施の形態を採用した画像形成装置に
おける現像装置の概略構成図である。
FIG. 1 is a schematic configuration diagram of a developing device in an image forming apparatus employing an embodiment of the present invention.

【図2】トナー像形成時における現像剤の挙動を表す概
略図である。
FIG. 2 is a schematic diagram illustrating a behavior of a developer when forming a toner image.

【符号の説明】[Explanation of symbols]

1 感光体ドラム 2 現像装置 3 支持ケース 3a 突出部 3b 対向面 4a 第一現像スリーブ 4b 第二現像スリーブ 5 現像剤収容部材 6a 第一現像ドクタ 6b 第二現像ドクタ 7 トナー 8 トナーホッパ 9 トナー供給開口部 10 トナーアジテータ 11 現像剤 12 トナーエンド検知手段 13 プレドクタ A 磁着部 B 循環部 C 滞留部 C′ 滞留部 REFERENCE SIGNS LIST 1 photosensitive drum 2 developing device 3 support case 3a projecting portion 3b facing surface 4a first developing sleeve 4b second developing sleeve 5 developer accommodating member 6a first developing doctor 6b second developing doctor 7 toner 8 toner hopper 9 toner supply opening DESCRIPTION OF SYMBOLS 10 Toner agitator 11 Developer 12 Toner end detection means 13 Predoctor A Magnetically attached part B Circulation part C Retention part C 'Retention part

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 内部に磁界発生手段を有し、トナーと磁
性キャリアとを含む二成分現像材を担持して搬送する第
一の現像剤担持体と、現像剤担持体に担持されて搬送さ
れる現像剤の量を規制する規制部材と、規制部材により
掻き落とされた現像剤を収容する現像剤収容部と、現像
材収容部に隣接し、現像剤担持体にトナーを供給するト
ナー収容部とを備え、第一の現像剤担持体上の現像剤の
トナー濃度の変化により、現像剤とトナーとの接触状態
を変化させて、現像剤担持体上のトナー取り込み状態を
変化させる現像装置において、 第二の現像剤担持体を有する ことを特徴とする現像蔵
置。
A first developer carrying member having a magnetic field generating means therein for carrying and transporting a two-component developer containing a toner and a magnetic carrier; and a first developer carrying member carried and transported by the developer carrying member. Regulating member for regulating the amount of developer to be supplied, a developer accommodating portion for accommodating the developer scraped off by the regulating member, and a toner accommodating portion which is adjacent to the developer accommodating portion and supplies toner to the developer carrier. A developing device that changes a contact state between the developer and the toner by changing a toner concentration of the developer on the first developer carrier, thereby changing a toner taking-in state on the developer carrier. A developer storage, comprising: a second developer carrier.
【請求項2】 請求項1に記載の現像装置において、 2つの現像剤担持体の最近接位置上下流側のそれぞれ対
向する部位に異なる磁極を配置する ことを特徴とする
現像装置。
2. The developing device according to claim 1, wherein different magnetic poles are arranged at opposing portions on the upstream and downstream sides of the closest positions of the two developer carriers.
【請求項3】 請求項1に記載の現像装置において、2
つの現像体担持体の電位を同一にする ことを特徴とす
る現像装置。
3. The developing device according to claim 1, wherein
A developing device, wherein the potentials of the two developer carrying members are made equal.
JP2001005146A 2001-01-12 2001-01-12 Developing device Pending JP2002214911A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001005146A JP2002214911A (en) 2001-01-12 2001-01-12 Developing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2001005146A JP2002214911A (en) 2001-01-12 2001-01-12 Developing device

Publications (1)

Publication Number Publication Date
JP2002214911A true JP2002214911A (en) 2002-07-31

Family

ID=18873230

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2001005146A Pending JP2002214911A (en) 2001-01-12 2001-01-12 Developing device

Country Status (1)

Country Link
JP (1) JP2002214911A (en)

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