JPS61200561A - Carrier recovering device - Google Patents
Carrier recovering deviceInfo
- Publication number
- JPS61200561A JPS61200561A JP60041628A JP4162885A JPS61200561A JP S61200561 A JPS61200561 A JP S61200561A JP 60041628 A JP60041628 A JP 60041628A JP 4162885 A JP4162885 A JP 4162885A JP S61200561 A JPS61200561 A JP S61200561A
- Authority
- JP
- Japan
- Prior art keywords
- carrier
- magnetic
- bias
- developer
- carrier recovery
- 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
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
- G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Magnetic Brush Developing In Electrophotography (AREA)
- Dry Development In Electrophotography (AREA)
Abstract
Description
【発明の詳細な説明】
狐呆よΔ机且分凱
本発明は、キャリア回収装置、詳しくはキャリアとトナ
ーとの混合物からなる2成分系現像剤を用いて、静電潜
像担体の表面に担持される静電潜像を現像する現像装置
に付設されるキャリア回収装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention uses a carrier recovery device, specifically, a two-component developer consisting of a mixture of carrier and toner, to coat the surface of an electrostatic latent image carrier. The present invention relates to a carrier recovery device attached to a developing device that develops a carried electrostatic latent image.
従来技術とその問題点
一般に、前記現像装置としては、静電潜像担体の表面に
対向して設けた現像スリーブと、外周部にN、S極を周
方向に順次着磁し現像スリーブの内部に設けた磁気ロー
ラとを備えたものが良く知られている。そして、この現
像装置において、キャリアとトナーとの混合物からなる
現像剤は、磁気ローラの磁気作用によって現像スリーブ
の外周面上に磁気刷子状に吸着され、現像スリーブ及び
/又は磁気ローラの回転に基づいて現像スリーブの外周
面に沿って現像領域、即ち静電潜像担体の表面と現像ス
リーブの外周面とが近接対向する領域へと搬送され、こ
こで静電潜像担体の表面に担持される静電潜像を現像す
る。この際、現像領域へと搬送されてきた現像剤中のト
ナーは、キャリアとの摩擦によって静電潜像画像部の極
性と同極性の摩擦帯電電荷を既に保持している関係上、
前記静電潜像画像部に対して静電的に吸着される。−方
、現像剤中のキャリアは前記磁気ローラの磁気作用によ
って現像スリーブの外周面に磁気的に吸引されているた
めに静電潜像担体へは付着することがない。Prior art and its problems In general, the developing device includes a developing sleeve provided facing the surface of an electrostatic latent image carrier, and an N and S pole magnetized sequentially in the circumferential direction on the outer periphery of the developing sleeve. A well-known device is equipped with a magnetic roller provided at the top. In this developing device, the developer consisting of a mixture of carrier and toner is attracted like a magnetic brush onto the outer circumferential surface of the developing sleeve by the magnetic action of the magnetic roller, and based on the rotation of the developing sleeve and/or the magnetic roller. The image is transported along the outer circumferential surface of the developing sleeve to the developing area, that is, the area where the surface of the electrostatic latent image carrier and the outer circumferential surface of the developing sleeve closely face each other, where it is carried on the surface of the electrostatic latent image carrier. Develop the electrostatic latent image. At this time, the toner in the developer that has been transported to the development area already holds a triboelectric charge of the same polarity as the polarity of the electrostatic latent image area due to friction with the carrier.
It is electrostatically attracted to the electrostatic latent image portion. On the other hand, the carrier in the developer is magnetically attracted to the outer circumferential surface of the developing sleeve by the magnetic action of the magnetic roller, so that it does not adhere to the electrostatic latent image carrier.
しかしながら、現実問題としては、現像時に若干量のキ
ャリアが静電潜像担体へと付着することが経験されてお
り、キャリアの現像装置外への漏出、現像剤の減少によ
る画像ムラ等の問題点を生じている。そして、この様な
キャリア付着は、キャリアとして小粒径のもの、磁性の
弱いもの、例えば樹脂中に磁性微粉末を分散したもの等
が使用された場合に生じ易いことが併せて経験されてい
る。However, as a practical matter, it has been experienced that a small amount of carrier adheres to the electrostatic latent image carrier during development, resulting in problems such as carrier leakage outside the developing device and image unevenness due to a decrease in developer. is occurring. Additionally, it has been experienced that such carrier adhesion is more likely to occur when a carrier with a small particle size or weak magnetism is used, such as a carrier in which fine magnetic powder is dispersed in a resin. .
そのため、従来では、例えば実公昭51−38363号
公報に記載の如く、磁性回収器を感光体ドラムに対向す
る様にして取付けたものが提案されている。しかしなが
ら、このものでは、磁性回収器の静磁場のみによって感
光体ドラムの表面に付着したキャリアを回収しようとす
るものであるため、十分な回収能力を発揮し得ないとい
う問題点を有している。特に、プロセス速度が高速化さ
れた複写機や光ビーム等にて形成された静電潜像を反転
現像して顕像化するプリンタ、キャリア付着が生じ易い
バインダタイプや有機系の感光体を使用した複写機の現
像装置には不十分である。For this reason, it has been proposed in the past, for example, as described in Japanese Utility Model Publication No. 51-38363, in which a magnetic recovery device is mounted to face the photosensitive drum. However, this method has the problem of not being able to exhibit sufficient recovery ability because it attempts to recover carriers attached to the surface of the photoreceptor drum only using the static magnetic field of the magnetic recovery device. . In particular, copying machines with high process speeds, printers that reversely develop and visualize electrostatic latent images formed with light beams, etc., and binder-type or organic photoreceptors that tend to cause carrier adhesion are used. This is insufficient for the developing device of a copying machine.
一方、本出願人によって、特開昭58−176661号
公報として、磁気ローラを備えたキャリア回収部材を静
電潜像担体の表面に対向して設けたものが提案され、こ
れには、キャリア回収部材に対して直流のバイアスを印
加すればキャリア回収能力が向上する旨開示されている
。しかしながら、直流電圧は安全規格上高電圧を印加す
ることはできず、特にキャリアの回収に高電圧のバイア
スを必要とする反転現像等では依然として回収効率の向
上を期待できないという問題点を有している。即ち、反
転現像の場合、キャリア付着は静電潜像の背影部電位と
現像スリーブへのバイアス電位との差に基づいて生じる
のであり、このキャリアを回収部材に再付着させるには
、回収部材と静電潜像担体との間に前記電位差によって
生じる電界以上の電界が作用する様に、回収部材に高電
圧の直流バイアスを印加する必要があるからである。On the other hand, the present applicant has proposed a carrier recovery member equipped with a magnetic roller as opposed to the surface of an electrostatic latent image carrier as JP-A-58-176661. It is disclosed that carrier recovery ability can be improved by applying a direct current bias to the member. However, DC voltage cannot be applied at a high voltage due to safety standards, and there is still a problem that improvement in recovery efficiency cannot be expected, especially in reverse development, etc., which requires a high voltage bias for carrier recovery. There is. That is, in the case of reversal development, carrier adhesion occurs based on the difference between the back shadow potential of the electrostatic latent image and the bias potential to the developing sleeve. This is because it is necessary to apply a high voltage DC bias to the collecting member so that an electric field greater than the electric field generated by the potential difference acts between the collecting member and the electrostatic latent image carrier.
問題点を解決するための手段
そこで、本発明に係るキャリア回収装置は、現像領域後
方の静電潜像担体表面に近接せしめて設置した非磁性導
電材からなるキャリア回収部材と、該キャリア回収部材
にキャリアを吸引可能な極性の直流バイアスを印加する
直流バイアス電源と、前記キャリア回収部材に前記直流
バイアスに重畳して交流バイアスを印加する交流バイア
ス電源とを備えたことを特徴とする。Means for Solving the Problems Therefore, the carrier recovery device according to the present invention includes a carrier recovery member made of a non-magnetic conductive material installed close to the surface of the electrostatic latent image carrier behind the development area, and the carrier recovery member. The present invention is characterized by comprising: a DC bias power supply that applies a DC bias with a polarity capable of attracting carriers; and an AC bias power supply that applies an AC bias to the carrier recovery member in a manner superimposed on the DC bias.
衷員或
[第1実施例、第1図参照]
第1図は本発明に係るキャリア回収装置の第1実施例を
備えた磁気刷子現像装置(MD)を示し、感光体ドラム
(1)は176mll1/secの周速度で矢印(a)
方向に回転駆動され、その回転に伴って図示しない周知
の作像装置により表面に静電潜像が形成される様になっ
ている。[First Embodiment, see FIG. 1] FIG. 1 shows a magnetic brush developing device (MD) equipped with a first embodiment of the carrier recovery device according to the present invention, in which the photoreceptor drum (1) is Arrow (a) at a circumferential speed of 176ml1/sec
With the rotation, an electrostatic latent image is formed on the surface by a well-known image forming device (not shown).
現像装置(MD)は、概略、現像槽(2)内であって感
光体ドラム(1)の表面の対向する位置に設けられた現
像スリーブ(3)と、該現像スリーブ(3)の内部に設
けた磁気ローラ(4)と、現像槽(2)の内部に収容さ
れている現像剤(De)中にほぼ下半分が埋設した状態
で設置されたパケットローラ(5)とから構成されてい
る。The developing device (MD) generally includes a developing sleeve (3) provided in a developing tank (2) at opposing positions on the surface of the photoreceptor drum (1), and a developing sleeve (3) provided inside the developing sleeve (3). It consists of a magnetic roller (4) and a packet roller (5) installed with its lower half almost buried in the developer (De) housed inside the developer tank (2). .
前記現像スリーブ(3)は非磁性導電材(例えば非磁性
ステンレス)にて外径31mmの筒状に形成したもので
、現像バイアス電源(E、)にて直流電圧を印加される
様になっている。また、現像スリーブ(3)は現像領域
(A)において感光体ドラム(1)の表面に対して0
、7 mmのギャップを保ち、現像時には図示しない駆
動源によって矢印(b)方向に3Orpmの回転数で回
転駆動される。前記磁気ローラ(4)は外周部にS、N
極を10極順次周方向に着磁したもので、矢印(b)方
向に120 Orpmの回転数で回転駆動される。また
、磁気ローラ(4)の磁力は現像スリーブ(3)の外周
面において1000ガウスの磁界が形成される様に設定
されている。このため、現像スリーブ(3)の外周面に
供給された現像剤(De)は、現像スリーブ(3)の外
周面上に磁気刷子状に吸着され、現像時に矢印(c)方
向へと搬送される。The developing sleeve (3) is made of a non-magnetic conductive material (for example, non-magnetic stainless steel) and is formed into a cylindrical shape with an outer diameter of 31 mm, and is adapted to be applied with a DC voltage by a developing bias power source (E). There is. Further, the developing sleeve (3) is 0.0000 0.00000 with respect to the surface of the photoreceptor drum (1) in the development area (A).
, a gap of 7 mm is maintained, and during development, it is rotated at a rotation speed of 3 Orpm in the direction of arrow (b) by a drive source (not shown). The magnetic roller (4) has S and N on its outer periphery.
Ten poles are sequentially magnetized in the circumferential direction, and are rotated at a rotation speed of 120 Orpm in the direction of arrow (b). Further, the magnetic force of the magnetic roller (4) is set so that a magnetic field of 1000 Gauss is formed on the outer peripheral surface of the developing sleeve (3). Therefore, the developer (De) supplied to the outer peripheral surface of the developing sleeve (3) is attracted to the outer peripheral surface of the developing sleeve (3) like a magnetic brush, and is transported in the direction of arrow (c) during development. Ru.
前記現像槽(2)内に収容されている現像剤(De)は
、磁性キャリアと絶縁性トナーとの混合物からなり、雨
粒子の摩擦にて互いに異極に摩擦帯電する。なお、現像
剤の具体例は後述する。The developer (De) contained in the developer tank (2) is made of a mixture of a magnetic carrier and an insulating toner, and is triboelectrically charged to have different polarities due to the friction of rain particles. Note that specific examples of the developer will be described later.
前記パケットローラ(5)は周部に複数のパケットを設
けたもので、現像時には矢印(a)方向に回転駆動され
、パケットによって掬い上げた現像剤(De)を現像ス
リーブ(3)の外周面に供給する。The packet roller (5) is provided with a plurality of packets around its circumference, and is rotated in the direction of arrow (a) during development, and the developer (De) scooped up by the packets is transferred to the outer peripheral surface of the developing sleeve (3). supply to.
また、前記現像スリーブ(3)の下方に位置する外周面
に対しては、樹脂フィルム、金属薄板等の可撓性を有す
る非磁性材からなるスクレーパ板(6)とクリーニング
板(7)とが現像スリーブ(3)の回転方向[矢印(b
)]に対して追随する逆方向及び対向する順方向にそれ
ぞれ圧接する様に支持体(8)に貼着されている。Further, a scraper plate (6) and a cleaning plate (7) made of a flexible non-magnetic material such as a resin film or a thin metal plate are attached to the outer peripheral surface located below the developing sleeve (3). Rotation direction of the developing sleeve (3) [arrow (b)
)] is attached to the support (8) so as to be in pressure contact in the following reverse direction and in the opposing forward direction, respectively.
一方、現像スリーブ(3)の上方には上部ケーシング(
9)が設置されている。この上部ケーシング(9)の内
周面は現像スリーブ(3)の外周面上を搬送される現像
剤(De)によって摺擦される様に、現像スリーブ(3
)と同心円状の円弧面とされている。そして、hi炉ケ
ーシング9)の感光体ドラム(+)側の端部であって前
記円弧面の延長線上には、可撓性を有する絶縁性シール
板(10)が、その先端が感光体ドラム(1)の表面に
圧接する様に取付けられている。On the other hand, above the developing sleeve (3) there is an upper casing (
9) is installed. The inner circumferential surface of the upper casing (9) is rubbed by the developer (De) conveyed on the outer circumferential surface of the developing sleeve (3).
) is considered to be a concentric arc surface. At the end of the HI furnace casing 9) on the photoreceptor drum (+) side and on the extension line of the arcuate surface, there is provided a flexible insulating seal plate (10) whose tip is connected to the photoreceptor drum. It is attached so that it comes into pressure contact with the surface of (1).
また、現像スリーブ(3)の下方であって現像槽(2)
の開口端部には現像剤漏出防止板(11)が設置されて
いる。この漏出防止板(11)はアルミニウム、ステン
レス等の非磁性導電材からなり、トナーの帯電極性とは
逆極性の直流電圧を印加される様になっている。Also, the developer tank (2) is located below the developer sleeve (3).
A developer leakage prevention plate (11) is installed at the opening end of the developer. The leakage prevention plate (11) is made of a non-magnetic conductive material such as aluminum or stainless steel, and is adapted to be applied with a DC voltage having a polarity opposite to that of the toner.
さらに、前記スクレーパ板(6)の下方の現像槽(2)
内には現像剤輸送羽根(12)が矢印(e)方向に回転
駆動可能に設置されている。Further, a developer tank (2) below the scraper plate (6)
A developer transporting blade (12) is installed inside the developer transporting blade (12) so as to be rotatable in the direction of arrow (e).
キャリア回収装置はキャリア回収板(13)と、該キャ
リア回収板(13)にバイアスを印加するための直流バ
イアス電源(E、)と、これに交流バイアスに重畳印加
するための交流バイアス電源(E3)とから構成されて
いる。キャリア回収板(13)はアルミニウム、ステン
レス等の非磁性導電材からなり、現像スリーブ(3)の
外周面と前記現像剤漏出防止板(11)との間であって
、先端が現像領域(A)直後の感光体ドラム(1)の表
面に近接する位置に設置され、ナイフェツジ状の先端面
は感光体ドラム(1)の表面にほぼ沿っている。そして
、前記直流バイアス電源(E、)による直流バイアスは
、キャリア回収板(13)にキャリアを吸引可能な極性
とされている。The carrier recovery device includes a carrier recovery plate (13), a DC bias power supply (E3) for applying a bias to the carrier recovery plate (13), and an AC bias power supply (E3) for superimposing an AC bias on the carrier recovery plate (13). ). The carrier recovery plate (13) is made of a non-magnetic conductive material such as aluminum or stainless steel, and is located between the outer circumferential surface of the developing sleeve (3) and the developer leakage prevention plate (11), and its tip is located in the developing area (A). ) is installed at a position close to the surface of the photoreceptor drum (1) immediately after the photoreceptor drum (1), and the knife-shaped tip surface is substantially along the surface of the photoreceptor drum (1). The DC bias from the DC bias power source (E) has a polarity that can attract carriers to the carrier collection plate (13).
ここで、現像剤について詳述する。Here, the developer will be explained in detail.
現像剤は、磁性キャリアと絶縁性トナーとの混合物から
なり、磁性キャリアはトナーと摩擦帯電が可能で、抵抗
値が101′Ωcm以上の高抵抗を有し、粒径は5〜6
0μm(平均粒径40μm)で、樹脂中に磁性微粉末を
分散してなり、かつ磁性微粉末の粒子全体に占める割合
は50〜75wt%である。さらに具体的には、磁性キ
ャリアは、例えば絶縁性樹脂と磁性微粉末とを溶融混合
し、冷却することによって製造される。絶縁性樹脂とし
ては、ポリエチレン。ポリアクリル酸エステル、ポリメ
チルメタクリレートポリスチレン、スチレンアクリル重
合体、エポキシ樹脂、クマロン樹脂。The developer consists of a mixture of a magnetic carrier and an insulating toner, and the magnetic carrier can be triboelectrified with the toner, has a high resistance value of 101'Ωcm or more, and has a particle size of 5 to 6.
0 μm (average particle diameter: 40 μm), and is made by dispersing magnetic fine powder in a resin, and the proportion of the magnetic fine powder in the total particles is 50 to 75 wt%. More specifically, the magnetic carrier is manufactured by, for example, melt-mixing an insulating resin and magnetic fine powder and cooling the mixture. Polyethylene is used as an insulating resin. Polyacrylic acid ester, polymethyl methacrylate polystyrene, styrene acrylic polymer, epoxy resin, coumaron resin.
マイレン酸樹脂1石炭酸樹脂、弗素酸樹脂等が使用でき
る。また、磁性微粉末としては、Fetus。Malenic acid resin 1 Carbonic acid resin, fluoric acid resin, etc. can be used. Further, as the magnetic fine powder, Fetus is used.
Fed、、フェライト、マグネタイト等を適宜選択すれ
ばよい。一方、絶縁性トナーとしては従来より公知のも
のが使用でき、その平均粒径は5〜50μmで体積抵抗
は約to”Ωcm以上である。Fed, ferrite, magnetite, etc. may be selected as appropriate. On the other hand, as the insulating toner, conventionally known ones can be used, and the average particle size thereof is 5 to 50 .mu.m and the volume resistivity is about to'' Ωcm or more.
以上の構成において、現像槽(2)内の現像剤(De)
はパケットローラ(5)の矢印(d)方向の回転駆動に
伴ってパケットにより掬い上げられ、かつ磁気ローラ(
4)の磁力の及ぶ位置にまで搬送され、現像スリーブ(
3)の外周面に磁気刷子状に吸着されろ。そして、現像
スリーブ(3)及び磁気ローラ(4)の矢印(b)方向
の回転駆動に伴い、現像スリーブ(3)の外周面に沿っ
て矢印(C)方向へと搬送され[この搬送は専ら磁気ロ
ーラ(4)の回転に基づく]、現像領域(A)に到達す
る。この現像領域(A)において感光体ドラム(1)の
表面に現像剤(De)によって摺擦され、該表面に担持
される静電潜像が現像されることとなる。その後、現像
剤(De)はスクレーパ板(6)によって現像スリーブ
(3)の外肩部から掻き落されて現像槽(2)内に戻さ
れる。In the above configuration, the developer (De) in the developer tank (2)
is scooped up by the packet as the packet roller (5) rotates in the direction of arrow (d), and is scooped up by the magnetic roller (5).
The developing sleeve (
3) Be attracted to the outer peripheral surface like a magnetic brush. Then, as the developing sleeve (3) and the magnetic roller (4) are rotated in the direction of arrow (b), the developing sleeve (3) is transported along the outer circumferential surface of the sleeve (3) in the direction of arrow (C). based on the rotation of the magnetic roller (4)], the development area (A) is reached. In this development area (A), the surface of the photoreceptor drum (1) is rubbed by the developer (De), and the electrostatic latent image carried on the surface is developed. Thereafter, the developer (De) is scraped off from the outer shoulder of the developing sleeve (3) by a scraper plate (6) and returned to the developer tank (2).
ところで、前記現像領域(A)において静電潜像が現像
される際、現像剤(De)中の磁性キャリアの若干量が
感光体ドラム(1)の表面に付着され得る。磁性キャリ
アの付着された感光体ドラム(1)の表面は現像領域(
A)を通過して矢印(a)方向へと移動し、キャリア回
収板(13)が感光体ドラム(1)の表面に近接対向す
るキャリア除去領域(B)へ七至る。このキャリア除去
領域(B)において、感光体ドラム(1)の表面に付着
された磁性キャリアは、バイアス電源(Et)、 (E
3)にて印加される直流バイアスと交流バイアスとによ
ってキャリア回収板(13)に吸着されることとなる。By the way, when the electrostatic latent image is developed in the development area (A), some amount of the magnetic carrier in the developer (De) may adhere to the surface of the photoreceptor drum (1). The surface of the photosensitive drum (1) to which the magnetic carrier is attached is a developing area (
A) and moves in the direction of the arrow (a) to reach the carrier removal area (B) where the carrier recovery plate (13) closely opposes the surface of the photoreceptor drum (1). In this carrier removal region (B), the magnetic carriers attached to the surface of the photoreceptor drum (1) are removed by the bias power source (Et), (E
The carrier is adsorbed to the carrier recovery plate (13) by the DC bias and AC bias applied in step 3).
このため、前記現像領域(A)において感光体ドラム(
1)の表面に付着した磁性キャリアはこのキャリア除去
領域(B)において確実に感光体ドラム(1)の表面か
ら除去されることとなり、本現像装置(MD)によって
現像された後の感光体ドラム(1)の表面には実質的に
キャリア付着は生じていない。そして、キャリア回収板
(13)に付着した磁性キャリアは磁気ローラ(4)の
矢印(b)方向の回転に伴いその磁界の作用でキャリア
回収板(13)に沿って下方に移動し、現像槽(2)内
の現像剤(De)中に戻される。Therefore, in the development area (A), the photoreceptor drum (
The magnetic carrier attached to the surface of 1) is reliably removed from the surface of the photoreceptor drum (1) in this carrier removal area (B), and the photoreceptor drum after being developed by this developing device (MD). Substantially no carrier adhesion occurred on the surface of (1). Then, as the magnetic roller (4) rotates in the direction of arrow (b), the magnetic carrier attached to the carrier collection plate (13) moves downward along the carrier collection plate (13) due to the action of the magnetic field, and is moved downward into the developing tank. It is returned to the developer (De) in (2).
一方、現像領域(A)で粉煙となったトナーは上部では
シール板(lO)にて漏出を防止され、下部では電源(
El)にてトナー帯電極性とは逆極性の直流電圧を印加
されている漏出防止板(II)に吸着し、外部への漏出
を防止される。On the other hand, the toner that has turned into powder smoke in the development area (A) is prevented from leaking by the seal plate (lO) in the upper part, and the power source (1O) in the lower part.
El), the toner is adsorbed to the leakage prevention plate (II) to which a DC voltage of opposite polarity to the toner charging polarity is applied, and leakage to the outside is prevented.
ところで、前記キャリア回収板(13)に直流バイアス
に加えて交流バイアスを重畳印加するのは、次の理由に
よる。By the way, the reason why an alternating current bias is superimposed and applied to the carrier recovery plate (13) in addition to a direct current bias is as follows.
まず、キャリア回収板(13)にはキャリアを吸引可能
な極性の直流バイアスが印加されるが、交流バイアスを
重畳印加することにより、より強いキャリア吸引力を発
生せしめることが可能である。First, a DC bias with a polarity capable of attracting carriers is applied to the carrier collection plate (13), but by superimposing an AC bias, it is possible to generate a stronger carrier attraction force.
また、キャリア除去領域(B)には磁気ローラ(4)の
回転に基づく交番磁界に加えてキャリア回収板(13)
に印加される交流バイアスによっても電界が形成され、
これらの交番磁界及び電界の作用にて感光体ドラム(1
)の表面に付着したキャリアが撹乱されて振動し、感光
体ドラム(1)の表面から離れ易くなるためである。In addition, in the carrier removal area (B), in addition to an alternating magnetic field based on the rotation of the magnetic roller (4), a carrier collection plate (13) is applied.
An electric field is also formed by an alternating current bias applied to the
Due to the action of these alternating magnetic fields and electric fields, the photoreceptor drum (1
This is because the carrier attached to the surface of the photoreceptor drum (1) is disturbed and vibrates, making it easier to separate from the surface of the photoreceptor drum (1).
ここで、正規現像(ポジーポジ現像)と反転現像(ネガ
−ポジ現像)とに分けて、本第1実施例における現像バ
イアスやキャリア回収バイアス等の電圧値の具体例を下
表に示す。Here, specific examples of voltage values such as the developing bias and the carrier recovery bias in the first embodiment are shown in the table below, divided into regular development (positive-positive development) and reversal development (negative-positive development).
上表から明らかな様に、正規現像では静電潜像の非画像
部電位の極性とキャリアの帯電極性が同じであるため、
キャリアの感光体ドラム(1)への吸着力は比較的小さ
いと考えられる。それに対し、反転現像では前記両者の
極性が異なるためにキャリアの感光体ドラム(1)の表
面への吸着力が大きい。そこで、反転現像ではキャリア
回収板(夏3)に交流バイアスを重畳してより大きいキ
ャリア吸引力を発生させることが、正規現像に比べて重
要である。As is clear from the above table, in regular development, the polarity of the potential of the non-image area of the electrostatic latent image and the charged polarity of the carrier are the same.
It is considered that the adsorption force of the carrier to the photoreceptor drum (1) is relatively small. On the other hand, in reversal development, since the two polarities are different, the adsorption force of the carrier to the surface of the photoreceptor drum (1) is large. Therefore, in reversal development, it is important to generate a larger carrier suction force by superimposing an alternating current bias on the carrier collection plate (summer 3) than in regular development.
なお、前記反転現像において、キャリア回収直流バイア
スの電圧値は静電潜像の非画像部電圧値よりも高くする
ことが望ましい。また、キャリア回収交流バイアスの電
圧値はできるだけ高い値が望ましいが、500 V (
rms)程度でも効果的であった。In the reversal development, it is desirable that the voltage value of the carrier recovery DC bias be higher than the voltage value of the non-image area of the electrostatic latent image. In addition, it is desirable that the voltage value of the carrier recovery AC bias is as high as possible, but 500 V (
rms) was also effective.
[第2実施例、第2図参照]
この第2実施例はキャリア回収装置として、磁気ローラ
(15)を内蔵したキャリア回収スリーブ(14)を設
けたもので、磁気刷子現像装置(MD)自体は前記第1
実施例と同様の構成である。[Second Embodiment, see Figure 2] This second embodiment is equipped with a carrier recovery sleeve (14) containing a magnetic roller (15) as a carrier recovery device, and the magnetic brush developing device (MD) itself is the first
The configuration is similar to that of the embodiment.
即ち、キャリア回収スリーブ(14)は非磁性導電材(
例えば非磁性ステンレス)にて外径16n+mのの筒状
に形成したもので、現像領域(A)後方のキャリア除去
領域(B)に感光体ドラム(1)の表面に対して0 、
5 mmのギャップを保って設置され、前記第1実施例
と同様の直流バイアス電源(E、)及び交流バイアス電
源(E3)にてキャリ、ア回収のためのバイアスを印加
される様になっている。また、このキャリア回収スリー
ブ(14)の現像槽(2)側の外周面には、現像槽(2
)の内側面から立ち上ったスクレーパ板(16)の先端
が圧接している。That is, the carrier collection sleeve (14) is made of a non-magnetic conductive material (
For example, it is made of non-magnetic stainless steel (non-magnetic stainless steel) and is formed into a cylindrical shape with an outer diameter of 16n+m.
They were installed with a gap of 5 mm maintained, and a bias for carry and recovery was applied using the same DC bias power supply (E) and AC bias power supply (E3) as in the first embodiment. There is. Further, the outer peripheral surface of the carrier recovery sleeve (14) on the developer tank (2) side is provided with a
) is in pressure contact with the tip of the scraper plate (16) rising from the inner surface.
磁気ローラ(15)は外周部にS、N極を順次周方向に
着磁したもので、その磁力はスリーブ(14)の外周面
において700ガウスの磁界が形成される様に設定され
ている。また、この磁気ローラ(15)は回転自在であ
って現像スリーブ(3)に内蔵された磁気ローラ(4)
の磁界の作用を受け、磁気ローラ(4)の矢印(b)方
向の回転に追随して矢印(r)方向に300 rpmで
従動回転する。The magnetic roller (15) has S and N poles sequentially magnetized in the circumferential direction on its outer periphery, and its magnetic force is set so that a magnetic field of 700 Gauss is formed on the outer periphery of the sleeve (14). Further, this magnetic roller (15) is rotatable and is connected to a magnetic roller (4) built in the developing sleeve (3).
Under the action of the magnetic field, the magnetic roller (4) rotates in the direction of arrow (r) at 300 rpm following the rotation of the magnetic roller (4) in the direction of arrow (b).
以上の構成において、現像領域(A)で感光体ドラム(
1)の表面に付着したキャリアは、キャリア除去領域(
B)で、磁気ローラ(!5)の磁力及びバイアス電源(
Et)、 (E3)にて印加される直流バイアスと交流
バイアスとによってキャリア回収スリーブ(14)の外
周面に吸着されることとなる。スリーブ(14)の外周
面に吸着されたキャリアは磁気ローラ(15)の矢印(
f)方向への従動回転に伴つてスリーブ(14)の外周
面上を矢印(f)とは逆方向に搬送され、スクレーパ板
(16)によって現像槽(2)内へと掻き落され、前記
第1実施例と同様の作用効果を発揮する。また、キャリ
ア除去領域(B)から外部へ漏れ様とする粉煙トナーも
キャリアと共にキャリア回収スリーブ(14)の外周面
に付着し、現像槽(2)内へと戻される。In the above configuration, the photosensitive drum (
The carriers attached to the surface of 1) are removed from the carrier removal area (
B), the magnetic force of the magnetic roller (!5) and the bias power supply (
The carrier is attracted to the outer circumferential surface of the carrier recovery sleeve (14) by the DC bias and AC bias applied at steps Et) and (E3). The carrier attracted to the outer circumferential surface of the sleeve (14) moves along the arrow (
With the driven rotation in the direction f), the sleeve (14) is conveyed on the outer peripheral surface in the direction opposite to the arrow (f), and is scraped off into the developing tank (2) by the scraper plate (16). It exhibits the same effects as the first embodiment. In addition, the powder smoke toner leaking to the outside from the carrier removal area (B) also adheres to the outer circumferential surface of the carrier recovery sleeve (14) together with the carrier, and is returned into the developer tank (2).
なお、前記キャリア回収スリーブ(14)は矢印(f)
とは逆方向に回転駆動(60rpm程度まで)しても良
い。Note that the carrier collection sleeve (14) is indicated by the arrow (f).
It may be rotated in the opposite direction (up to about 60 rpm).
また、バイアス電源(Et)、 (E3)等の電圧値は
第1実施例で示した表と同様である。Further, the voltage values of the bias power supplies (Et), (E3), etc. are the same as those in the table shown in the first embodiment.
発明の効果
以上の説明で明らかな様に、本発明は、現像領域後方の
静電潜像担体表面に近接せしめて設置したキャリア回収
部材に、キャリアを吸引可能な極性の直流バイアスを交
流バイアスを重畳して印加する様:二したため、現像領
域で静電潜像担体表面に付着したキャリアを確実にキャ
リア回収部材に吸着せしめて静電潜像担体表面から除去
することができ、キャリアが以後の工程である転写部や
クリーニング部へ搬送されて種々のトラブルを生じたり
、画像ムラを生じたりすることがない。しかも、交流バ
イアスの重畳印加によってキャリア回収効率が一段と高
められ、特にキャリア付着が発生し易い反転現像等に有
効であるし、直流バイアスの電圧値を高めることなく確
実なキャリア回収ができ、安全でもある。Effects of the Invention As is clear from the above explanation, the present invention applies a direct current bias or an alternating current bias with a polarity capable of attracting carrier to a carrier recovery member installed close to the surface of the electrostatic latent image carrier at the rear of the developing area. By superimposing the applied voltages, the carrier adhering to the surface of the electrostatic latent image carrier in the developing area can be reliably adsorbed to the carrier collection member and removed from the surface of the electrostatic latent image carrier. There is no need to worry about various troubles caused by being transported to the transfer section or cleaning section, which are processes, or uneven images. Moreover, the carrier recovery efficiency is further improved by applying AC bias in a superimposed manner, which is particularly effective in reverse development where carrier adhesion is likely to occur. It is also possible to recover carrier reliably without increasing the voltage value of DC bias, making it safe. be.
【図面の簡単な説明】
第1図は本発明の第1実施例を備えた現像装置の断面図
、第2図は本発明の第2実施例を備えた現像装置の断面
図である。
(A)・・・現像領域、 (B)・・・キャリア除去領
域、(MD)・・・現像装置、 (De)・・・現像剤
、 (E、)・・・直流バイアス電源、 (E3)・・
・交流バイアス電源、 (13)・・・キャリア回収板
、 (14)・・・キャリア回収スリーブ、 (15)
・・・磁気ローラ。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a developing device equipped with a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a developing device equipped with a second embodiment of the present invention. (A)...Development area, (B)...Carrier removal area, (MD)...Development device, (De)...Developer, (E,)...DC bias power supply, (E3 )・・
・AC bias power supply, (13)...Carrier recovery plate, (14)...Carrier recovery sleeve, (15)
...Magnetic roller.
Claims (1)
剤を用いて、静電潜像担体の表面に担持される静電潜像
を現像する現像装置において、現像領域後方の静電潜像
担体表面に近接せしめて設置した非磁性導電材からなる
キャリア回収部材と、該キャリア回収部材にキャリアを
吸引可能な極性の直流バイアスを印加する直流バイアス
電源と、前記キャリア回収部材に前記直流バイアスに重
畳して交流バイアスを印加する交流バイアス電源とを備
えたことを特徴とするキャリア回収装置。1. In a developing device that develops an electrostatic latent image carried on the surface of an electrostatic latent image carrier using a two-component developer consisting of a mixture of carrier and toner, the electrostatic latent image carrier at the rear of the development area a carrier recovery member made of a non-magnetic conductive material installed close to the surface; a DC bias power source that applies a DC bias of a polarity capable of attracting carriers to the carrier recovery member; and an AC bias power source that applies an AC bias.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60041628A JPS61200561A (en) | 1985-03-01 | 1985-03-01 | Carrier recovering device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60041628A JPS61200561A (en) | 1985-03-01 | 1985-03-01 | Carrier recovering device |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS61200561A true JPS61200561A (en) | 1986-09-05 |
Family
ID=12613591
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP60041628A Pending JPS61200561A (en) | 1985-03-01 | 1985-03-01 | Carrier recovering device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS61200561A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6365050U (en) * | 1986-10-17 | 1988-04-28 | ||
JPH06130820A (en) * | 1992-10-16 | 1994-05-13 | Fuji Xerox Co Ltd | Image forming device |
JPH08227210A (en) * | 1995-02-22 | 1996-09-03 | Nec Data Terminal Ltd | Electrophotographic printer |
US7746619B2 (en) | 2007-04-27 | 2010-06-29 | Sendec Corporation | Soft start clutch controller |
US8320096B2 (en) | 2007-04-27 | 2012-11-27 | Global Digital Instruments Llc | Soft start clutch controller |
JP2013029673A (en) * | 2011-07-28 | 2013-02-07 | Ricoh Co Ltd | Developing device and image forming apparatus |
US8666294B2 (en) | 2009-10-23 | 2014-03-04 | Konica Minolta Business Technologies, Inc. | Carrier removing device and image forming apparatus |
-
1985
- 1985-03-01 JP JP60041628A patent/JPS61200561A/en active Pending
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6365050U (en) * | 1986-10-17 | 1988-04-28 | ||
JPH06130820A (en) * | 1992-10-16 | 1994-05-13 | Fuji Xerox Co Ltd | Image forming device |
JPH08227210A (en) * | 1995-02-22 | 1996-09-03 | Nec Data Terminal Ltd | Electrophotographic printer |
US7746619B2 (en) | 2007-04-27 | 2010-06-29 | Sendec Corporation | Soft start clutch controller |
US8320096B2 (en) | 2007-04-27 | 2012-11-27 | Global Digital Instruments Llc | Soft start clutch controller |
US8666294B2 (en) | 2009-10-23 | 2014-03-04 | Konica Minolta Business Technologies, Inc. | Carrier removing device and image forming apparatus |
JP2013029673A (en) * | 2011-07-28 | 2013-02-07 | Ricoh Co Ltd | Developing device and image forming apparatus |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JPS61200561A (en) | Carrier recovering device | |
US4493882A (en) | Image formation method and apparatus | |
JPS5817472A (en) | Cleaning method | |
JP4143229B2 (en) | Development device | |
JPS63293571A (en) | Carrier recovering device | |
JPS645705B2 (en) | ||
JPS629904B2 (en) | ||
JPS5882279A (en) | Magnetic brush developing device | |
JP2528650B2 (en) | Development device | |
JPS5865458A (en) | Developing device | |
JPH089729Y2 (en) | Development device | |
JPH05289594A (en) | Magnetic brush cleaning device | |
JPS628175A (en) | Developing device using single-component toner | |
JP2516380Y2 (en) | Development device | |
JPS62208079A (en) | Developing device | |
JPH023988B2 (en) | ||
JPS58176661A (en) | Magnetic brush developing device | |
JPS6053960A (en) | Formation of image | |
JPH0651639A (en) | Developing device | |
JPS5921028B2 (en) | Electrostatic latent image development method | |
JPS60241074A (en) | Developing device | |
JPS62234177A (en) | Developing device | |
JPS61248074A (en) | Cleaning device for copying machine or the like | |
JPS61240263A (en) | Image forming device | |
JPH07306568A (en) | Electrifying device |