JP2000330384A - Developing device, processing cartridge, and image forming device - Google Patents

Developing device, processing cartridge, and image forming device

Info

Publication number
JP2000330384A
JP2000330384A JP14000499A JP14000499A JP2000330384A JP 2000330384 A JP2000330384 A JP 2000330384A JP 14000499 A JP14000499 A JP 14000499A JP 14000499 A JP14000499 A JP 14000499A JP 2000330384 A JP2000330384 A JP 2000330384A
Authority
JP
Japan
Prior art keywords
magnetic
developer
magnetic pole
magnetic field
field generating
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
JP14000499A
Other languages
Japanese (ja)
Inventor
Masaaki Yamaji
雅章 山路
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP14000499A priority Critical patent/JP2000330384A/en
Publication of JP2000330384A publication Critical patent/JP2000330384A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To make the degree of freedom for composing magnetic pole structure on the magnetic field roller improved, while restraining/preventing the developer escape or the developer leak with regard to the impact. SOLUTION: The magnetic roller 32 consisted of the magnetic block 32a magnetized with the magnetic pole inside a developing sleeve 31 and the magnetic member 32b, is fixed/arranged respectively, and the magnetic sealing member 34 provided with plural magnetic poles with a specified gap on both end of the developing sleeve 31. The magnetic pole N2 in same polarity is arranged on the downstream side in the traveling direction of the developing sleeve 31 corresponding to the magnetic pole N13 on the outlet side in the developer traveling direction of the magnetic sealing member 34. The virtual positive magnetic field of NS is formed by inducing reverse polarity (S pole) on the magnetic member 32b of the magnetic roller opposite to the above magnetic pole N13.

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、例えば複写機ある
いはプリンタなどとされる電子写真方式あるいは静電記
録方式の画像形成装置、該画像形成装置に装着される現
像装置、およびプロセスカートリッジに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic or electrostatic recording type image forming apparatus such as a copying machine or a printer, a developing device mounted on the image forming apparatus, and a process cartridge.

【０００２】[0002]

【従来の技術】電子写真複写機、静電記録装置、磁気記
録装置などの画像形成装置においては、像担持体上の静
電潜像や磁気潜像を現像する現像装置として磁気ブラシ
現像装置が広く使用されている。2. Description of the Related Art In an image forming apparatus such as an electrophotographic copying machine, an electrostatic recording device, and a magnetic recording device, a magnetic brush developing device is used as a developing device for developing an electrostatic latent image or a magnetic latent image on an image carrier. Widely used.

【０００３】この磁気ブラシ現像装置の一例として、現
像剤を収容する現像容器に回転自在に取り付けた現像剤
担持体としての非磁性円筒体（以下、「現像スリーブ」
という）と、この現像スリーブ内に配置され、複数の磁
極を周面に有する、一般的には固定されている磁界発生
手段としての磁石ローラと、現像スリーブ上の現像剤の
層厚を規制する現像剤層厚規制手段としての規制ブレー
ドとを具備し、現像スリーブの回転により現像剤を搬送
するものが広く知られている。As an example of the magnetic brush developing device, a non-magnetic cylindrical body (hereinafter referred to as a "developing sleeve") as a developer carrier rotatably mounted on a developing container for accommodating a developer.
), A magnet roller which is disposed in the developing sleeve and has a plurality of magnetic poles on its peripheral surface and is generally fixed as a magnetic field generating means, and regulates the layer thickness of the developer on the developing sleeve. It is widely known that the image forming apparatus includes a regulating blade as a developer layer thickness regulating means, and conveys the developer by rotating a developing sleeve.

【０００４】この種の現像装置は、現像剤の汚染を防止
するために、現像領域外の両端部では現像剤を搬送しな
いように、現像スリーブ両端部に現像剤の供給を阻止す
る端部規制手段を設けたり、現像スリーブへ供給された
現像剤が現像領域外へ流出するのを防止するために、回
転する現像スリーブの両端部にシール部材を設けてい
る。In order to prevent the developer from being contaminated, the developing device of this type does not convey the developer at both ends outside the developing area. In order to provide means and prevent the developer supplied to the developing sleeve from flowing out of the developing area, seal members are provided at both ends of the rotating developing sleeve.

【０００５】ところで、従来、上述の画像形成装置にお
いて、像担持体としての電子写真感光体およびこの電子
写真感光体に作用するプロセス手段を一体的にカートリ
ッジ化して、このカートリッジを画像形成装置本体に着
脱可能とするプロセスカートリッジ方式が知られてい
る。このプロセスカートリッジ方式によれば、装置のメ
ンテナンスをサービスマンによらずにユーザー自身で行
うことができるので、格段に操作性を向上させることが
できる。そのため、このプロセスカートリッジ方式は画
像形成装置において広く用いられている。Conventionally, in the above-described image forming apparatus, an electrophotographic photosensitive member as an image carrier and a process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is mounted on an image forming apparatus main body. A detachable process cartridge system is known. According to this process cartridge system, maintenance of the apparatus can be performed by the user himself without relying on a service person, so that operability can be remarkably improved. Therefore, the process cartridge system is widely used in image forming apparatuses.

【０００６】このようなプロセスカートリッジに内蔵さ
れた現像手段（現像装置）においては、回転する現像ス
リーブの両端部に現像領域外へ現像剤が流出するのを防
止するため、あるいはプロセスカートリッジが装置本体
に対して着脱される際に衝撃を受けても現像剤がもれな
いようにするためのシール部材が設けてある。従来のこ
の現像剤の流出を防ぐシール部材にはフェルトや発泡ゴ
ムなどの弾性体が広く利用されている。その代表的な例
を図１８と図１９に示す。In such a developing means (developing device) built in the process cartridge, the developer is prevented from flowing out of the developing area to both ends of the rotating developing sleeve, or the process cartridge is provided in the main assembly of the apparatus. A seal member is provided to prevent the developer from leaking even when subjected to an impact when being attached to or detached from the printer. Elastic bodies such as felt and foam rubber are widely used as conventional seal members for preventing the developer from flowing out. Representative examples are shown in FIGS.

【０００７】現像スリーブ２３１はその内部に磁石ロー
ラ２３２を有し、現像容器２３０にスリーブ軸受２３７
を介して回転可能に支持されている。従って、現像容器
２３０から供給された現像剤は磁石ローラ２３２の磁力
により現像スリーブ２３１の表面に付着し、規制ブレー
ド２３３により層厚が一定に規制された後、現像スリー
ブ２３１の回転に伴って不図示の電子写真感光体上の潜
像と対向する位置においてこの潜像に付着して現像を行
う。The developing sleeve 231 has a magnet roller 232 inside, and a sleeve bearing 237
It is rotatably supported through. Therefore, the developer supplied from the developing container 230 adheres to the surface of the developing sleeve 231 by the magnetic force of the magnet roller 232, and after the thickness of the developing sleeve 231 is regulated by the regulating blade 233, the developer is not allowed to rotate. At the position facing the latent image on the illustrated electrophotographic photosensitive member, the latent image is adhered to the latent image for development.

【０００８】現像スリーブ２３１の現像領域より外側の
長手方向の両端部で、現像容器２３０に装着される現像
スリーブ２３１の開口部と反対側の奥部には弾性シール
部材２３６が取り付けられており、この弾性シール部材
２３６を現像スリーブ２３１の外周面に圧接させること
により現像剤の流出を防止している。An elastic seal member 236 is attached to both ends of the developing sleeve 231 in the longitudinal direction outside the developing region and at the back of the developing sleeve 231 mounted on the developing container 230 on the opposite side to the opening. The elastic seal member 236 is pressed against the outer peripheral surface of the developing sleeve 231 to prevent the developer from flowing out.

【０００９】しかしながら、このような構成の現像装置
２００では、現像スリーブ２３１の外周面の半分に弾性
シール部材２３６が圧接しているため、現像動作時に回
転する現像スリーブ２３１の負荷が大きく、また現像ス
リーブ２３１との接触により弾性シール部材２３６が劣
化し、シール性が悪化するなどの問題があった。更に、
現像スリーブ２３１と弾性シール部材２３６との間にわ
ずかではあるがトナーが侵入してしまう場合があり、こ
れが原因でトルクが高くなったり、トルクの変動が大き
くなって回転ムラが生じ、画像形成に悪影響を及ぼすこ
とがあった。However, in the developing device 200 having such a configuration, since the elastic seal member 236 is in pressure contact with half of the outer peripheral surface of the developing sleeve 231, the load on the developing sleeve 231 that rotates during the developing operation is large, and the developing There has been such a problem that the elastic seal member 236 is deteriorated due to the contact with the sleeve 231 and the sealing performance is deteriorated. Furthermore,
Although a small amount of toner may enter between the developing sleeve 231 and the elastic seal member 236, the torque may be increased, or the fluctuation of the torque may be increased to cause rotation unevenness. May have adverse effects.

【００１０】そのため、これらの問題を解決すべく現像
スリーブ２３１の両端部に一定の間隙をもって磁石シー
ル部材を配置し、これにより現像剤の流出を防止する方
法が提案されている。Therefore, in order to solve these problems, a method has been proposed in which magnet seal members are disposed at both ends of the developing sleeve 231 with a certain gap, thereby preventing the developer from flowing out.

【００１１】図２０に上記磁石シール部材３３４を備え
た現像装置３００を示し、図２１には磁石シール部材３
３４の着磁パターンを示す。FIG. 20 shows a developing device 300 provided with the magnet seal member 334, and FIG.
34 shows a magnetization pattern of No. 34.

【００１２】図２０に示すように、磁石シール部材３３
４はその内部に磁石ローラ３３２を内包した現像スリー
ブ３３１の外周面に対して一定の間隙ｇを隔てて、現像
スリーブ３３１の両端部に配設され、この状態で現像ス
リーブ３３１とともに現像容器３３０に取り付けられて
いる。また、磁石シール部材３３４は磁石から構成され
たもので、図２１に示したように、内周面にＮＳ極を多
磁極に着磁している。As shown in FIG. 20, a magnet seal member 33 is provided.
Numerals 4 are disposed at both ends of the developing sleeve 331 with a predetermined gap g from the outer peripheral surface of the developing sleeve 331 in which the magnet roller 332 is incorporated. Installed. The magnet seal member 334 is made of a magnet, and has NS poles magnetized on the inner peripheral surface thereof to multiple magnetic poles as shown in FIG.

【００１３】この技術的手段を用いると、現像スリーブ
３３１と磁石シール部材３３４とを非接触にできるの
で、現像スリーブ３３１の回転トルクは著しく小さく、
従って、駆動モータも小型で低価格のものでよく、ま
た、回転トルクの変動も小さく、現像スリーブ３３１や
電子写真感光体の回転ムラが生じにくくなるので、磁石
シール部材３３４の摩耗などもなくなり、そのため磁石
シール部材３３４は半永久的に使用でき、またリサイク
ルにも対応可能である。When this technical means is used, the developing sleeve 331 and the magnet seal member 334 can be brought into non-contact, so that the rotational torque of the developing sleeve 331 is extremely small,
Therefore, the drive motor may be small and inexpensive, the fluctuation of the rotation torque is small, and the rotation unevenness of the developing sleeve 331 and the electrophotographic photoreceptor is hardly generated. Therefore, the magnet seal member 334 can be used semi-permanently and can be recycled.

【００１４】ところで、従来、図２２と図２３に示すよ
うに、規制ブレード４３３、５３３と対向して現像スリ
ーブ４３１、５３１内部に磁極を配置し、磁極を利用し
て現像剤の厚みを効果的に規制しているものが広く用い
られている。図２２と図２３に示すように、この規制磁
極Ｎ２が規制ブレード４３３、５３３の下流側に配置し
たものが広く知られている。図２２は、規制ブレード４
３３として磁性部材を用いた例における規制磁極Ｎ２と
の配置関係を示し、図２３は規制ブレード５３３として
弾性ブレードを用いた例における規制磁極Ｎ２との配置
関係を示した模式図である。Conventionally, as shown in FIGS. 22 and 23, magnetic poles are arranged inside the developing sleeves 431 and 531 in opposition to the regulating blades 433 and 533, and the thickness of the developer is effectively reduced by utilizing the magnetic poles. Are widely used. As shown in FIGS. 22 and 23, it is widely known that the regulating magnetic pole N2 is arranged downstream of the regulating blades 433, 533. FIG. 22 shows the regulating blade 4
FIG. 23 is a schematic diagram showing an arrangement relationship with the regulating magnetic pole N2 in an example using a magnetic member as 33, and FIG. 23 is an illustration showing an arrangement relationship with the regulating magnetic pole N2 in an example using an elastic blade as the regulating blade 533.

【００１５】このような構成によれば、規制磁極Ｎ２を
規制ブレード４３３、５３３の下流側に配置することで
現像剤の負荷を軽減でき、現像剤の長寿命化を達成でき
るという効果がある。According to such a configuration, by arranging the regulating magnetic pole N2 on the downstream side of the regulating blades 433, 533, it is possible to reduce the load on the developer and to achieve a longer life of the developer.

【００１６】[0016]

【発明が解決しようとする課題】しかしながら、上記構
成では、使用状況により下記のような問題が生ずる場合
があった。However, in the above configuration, the following problems may occur depending on the use situation.

【００１７】例えば、一般的に磁石シール部材３３４の
取り付けは型枠にはめ込む方法が用いられているが、図
２２、２３に示したように、規制磁極Ｎ２を規制ブレー
ド４３３、５３３の下流側に配置している場合、磁石ロ
ーラ３３２の規制磁極Ｎ２に対向した領域まで磁石シー
ル部材３３４を配設すると、磁石シール部材３３４を挿
入すべき型枠の形状が複雑になり、コストが高くなった
り、型枠が他の部材とぶつからないように取り付ける必
要があった。For example, a method of fitting the magnet seal member 334 into a mold is generally used. However, as shown in FIGS. 22 and 23, the regulating magnetic pole N2 is placed downstream of the regulating blades 433 and 533. In the case where the magnet seal member 334 is arranged, if the magnet seal member 334 is arranged up to the region facing the regulating magnetic pole N2 of the magnet roller 332, the shape of the mold in which the magnet seal member 334 is inserted becomes complicated, and the cost increases. It was necessary to attach the mold so that it did not hit other members.

【００１８】また、図２２、２３に示すように、磁石ロ
ーラ３３２の磁極Ｎ１が電子写真感光体１に近接してい
る場合、磁石ローラ３３２の磁極Ｎ１に対向した領域ま
で磁石シール部材３３４を配設すると、磁石シール部材
３３４と電子写真感光体１がぶつかり、電子写真感光体
１が損傷する場合があり、また、これを防ぐためには取
り付け精度を高度に設定しなければならず、コストが高
くなるという問題があった。Further, as shown in FIGS. 22 and 23, when the magnetic pole N1 of the magnet roller 332 is close to the electrophotographic photosensitive member 1, a magnet seal member 334 is arranged to a region facing the magnetic pole N1 of the magnet roller 332. If it is provided, the magnet seal member 334 and the electrophotographic photosensitive member 1 may collide with each other and damage the electrophotographic photosensitive member 1, and in order to prevent this, the mounting accuracy must be set to a high degree, and the cost is high. There was a problem of becoming.

【００１９】本発明は上記従来技術を更に発展させたも
のである。The present invention is a further development of the above prior art.

【００２０】従って、本発明の主な目的は、現像剤のす
り抜けや衝撃に対する現像剤もれを抑制・防止しなが
ら、磁界発生手段の磁極構成の自由度を向上させた現像
装置、この現像装置を備えたプロセスカートリッジおよ
び画像形成装置を提供することである。Therefore, a main object of the present invention is to provide a developing apparatus and a developing apparatus in which the degree of freedom of the magnetic pole configuration of the magnetic field generating means is improved while suppressing or preventing the developer from leaking or impacting the developer. To provide a process cartridge and an image forming apparatus having the same.

【００２１】本発明の他の目的は、現像剤のすり抜けや
衝撃に対する現像剤もれを抑制・防止し、現像剤の長寿
命化を図りながら、簡素化した構成で安価な現像装置、
この現像装置を備えたプロセスカートリッジおよび画像
形成装置を提供することである。Another object of the present invention is to provide an inexpensive developing apparatus having a simplified configuration while suppressing and preventing the leakage of the developer due to the passage of the developer and impact, and extending the life of the developer.
An object of the present invention is to provide a process cartridge and an image forming apparatus provided with the developing device.

【００２２】本発明の更に他の目的は、現像剤のすり抜
けや衝撃に対する現像剤もれを抑制・防止し、像担持体
が損傷することなく、また、磁石シール部材の取り付け
精度の許容範囲を大きくした現像装置、この現像装置を
備えたプロセスカートリッジおよび画像形成装置を提供
することである。Still another object of the present invention is to suppress or prevent the leakage of the developer due to the penetration or impact of the developer, to prevent the image carrier from being damaged, and to set the allowable range of the mounting accuracy of the magnet seal member. An object of the present invention is to provide an enlarged developing device, a process cartridge provided with the developing device, and an image forming apparatus.

【００２３】[0023]

【課題を解決するための手段】上記目的は本発明に係る
現像装置、プロセスカートリッジ、および画像形成装置
にて達成される。要約すれば、本発明は、磁性現像剤を
収容する現像容器と、該現像容器に回転自在に支持さ
れ、複数の磁極を備えた磁界発生手段を内部に固定配置
することにより磁性現像剤を担持搬送する現像剤担持体
とを有する現像装置において、前記現像剤担持体の両端
部にその外周面と所定間隙をもって配置された複数の磁
極を備えた磁石シール部材を有し、前記磁石シール部材
は、前記磁石シール部材の前記現像剤担持体移動方向端
部の端部磁極と、前記端部磁極と対応する前記磁界発生
手段の少なくとも一つの前記磁極とがずれるように配置
され、前記端部磁極と対応する前記磁界発生手段の前記
磁極とは同極性として、前記磁界発生手段の前記端部磁
極と対向する部位に逆極性の磁極を誘起させて仮想的に
ＮＳの順磁界を形成させることを特徴とする現像装置で
ある。The above object is achieved by a developing device, a process cartridge, and an image forming apparatus according to the present invention. In summary, the present invention carries a magnetic developer by fixedly arranging therein a developing container containing a magnetic developer and a magnetic field generating means rotatably supported by the developing container and having a plurality of magnetic poles. A developing device having a developer carrier to be conveyed, a magnet seal member having a plurality of magnetic poles disposed at both ends of the developer carrier with a predetermined gap from an outer peripheral surface thereof, wherein the magnet seal member is An end magnetic pole at an end of the magnet seal member in the developer carrier moving direction and at least one magnetic pole of the magnetic field generating means corresponding to the end magnetic pole, the end magnetic pole The magnetic poles of the magnetic field generating means corresponding to the same polarity have the same polarity, and a magnetic pole of opposite polarity is induced in a portion of the magnetic field generating means facing the end magnetic pole to virtually form a forward magnetic field of NS. Characteristic A developing device for.

【００２４】本発明による他の態様によれば、磁性現像
剤を収容する現像容器と、該現像容器に回転自在に支持
され、内部に磁界発生手段を固定配置することにより磁
性現像剤を担持搬送する現像剤担持体とを有する現像装
置において、前記現像剤担持体の両端部に、前記現像剤
担持体の外周面と所定間隙をもって磁石シール部材を配
置し、前記磁石シール部材の前記現像剤担持体と対向す
る領域の現像剤搬送方向出口側の部位に出口側磁極を配
置し、前記出口側磁極よりも前記現像剤担持体移動方向
下流側に前記磁界発生手段の磁極を配置し、前記磁界発
生手段の磁極と前記磁石シール部材の前記出口側磁極と
を同極性として、前記磁界発生手段の前記出口側磁極と
対向する部位に逆極性の磁極を誘起させて仮想的にＮＳ
の順磁界を形成させることを特徴とする現像装置が提供
される。According to another aspect of the present invention, a developing container for containing a magnetic developer, and a magnetic field generating means fixedly disposed inside the developing container and rotatably supported by the developing container, carry and carry the magnetic developer. A magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface of the developer carrier, and the developer carrier of the magnet seal member is disposed at both ends of the developer carrier. An exit-side magnetic pole is disposed in a region on the exit side of the developer transporting direction in a region facing the body, and a magnetic pole of the magnetic field generating means is disposed downstream of the exit-side magnetic pole in the developer carrier moving direction; The magnetic pole of the generating means and the outlet-side magnetic pole of the magnet seal member have the same polarity, and a magnetic pole of the opposite polarity is induced in a portion of the magnetic field generating means opposite to the outlet-side magnetic pole to virtually NS.
And a developing device for forming a forward magnetic field.

【００２５】また、本発明による他の態様によれば、磁
性現像剤を収容する現像容器と、該現像容器に回転自在
に支持され、内部に磁界発生手段を固定配置することに
より磁性現像剤を担持搬送する現像剤担持体とを有する
現像装置において、前記現像剤担持体の両端部に、前記
現像剤担持体の外周面と所定間隙をもって磁石シール部
材を配置し、前記磁石シール部材の前記現像剤担持体と
対向する領域の現像剤搬送方向入口側の部位に入口側磁
極を配置し、前記出口側磁極よりも前記現像剤担持体移
動方向上流側に前記磁界発生手段の磁極を配置し、前記
磁界発生手段の磁極と前記磁石シール部材の入口側磁極
を同極性として、前記磁界発生手段の前記入口側磁極と
対向する部位に逆極性の磁極を誘起させて仮想的にＮＳ
の順磁界を形成させることを特徴とする現像装置が提供
される。According to another aspect of the present invention, a magnetic developer is accommodated in a developing container for accommodating the magnetic developer, and the magnetic developer is rotatably supported by the developing container and a magnetic field generating means is fixed inside the developing container. In a developing device having a developer carrier for carrying and transporting, a magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from an outer peripheral surface of the developer carrier, and the developing of the magnet seal member is performed. An inlet-side magnetic pole is arranged at a portion on the developer transport direction entrance side of a region opposed to the developer carrier, and a magnetic pole of the magnetic field generating means is arranged on the upstream side of the developer carrier moving direction from the outlet-side magnetic pole, The magnetic pole of the magnetic field generating means and the magnetic pole on the entrance side of the magnet seal member have the same polarity, and a magnetic pole of the opposite polarity is induced in a portion of the magnetic field generating means opposite to the magnetic pole on the inlet side to virtually NS.
And a developing device for forming a forward magnetic field.

【００２６】更に、本発明による他の態様によれば、画
像形成装置本体に着脱可能なプロセスカートリッジにお
いて、少なくとも電子写真感光体と、現像装置とを有
し、前記現像装置は、磁性現像剤を収容する現像容器
と、該現像容器に回転自在に支持され、複数の磁極を備
えた磁界発生手段を内部に固定配置することにより磁性
現像剤を担持搬送する現像剤担持体と、前記現像剤担持
体の両端部にその外周面と所定間隙をもって配置された
複数の磁極を備えた磁石シール部材と、を有し、前記磁
石シール部材は、前記磁石シール部材の前記現像剤担持
体移動方向端部の端部磁極と、前記端部磁極と対応する
前記磁界発生手段の少なくとも一つの前記磁極とがずれ
るように配置され、前記端部磁極と対応する前記磁界発
生手段の前記磁極とを同極性として、前記磁界発生手段
の前記端部磁極と対向する部位に逆極性の磁極を誘起さ
せて仮想的にＮＳの順磁界を形成させることを特徴とす
るプロセスカートリッジが提供される。Further, according to another aspect of the present invention, a process cartridge detachably mountable to an image forming apparatus main body includes at least an electrophotographic photosensitive member and a developing device, wherein the developing device uses a magnetic developer. A developer container for housing, a developer carrier rotatably supported by the developer container, and a magnetic field generating means having a plurality of magnetic poles fixedly disposed therein for carrying and transporting a magnetic developer; A magnet seal member having a plurality of magnetic poles disposed at both ends of the body with an outer peripheral surface thereof with a predetermined gap therebetween, wherein the magnet seal member is an end portion of the magnet seal member in the developer carrier moving direction. The end magnetic poles are arranged so that at least one magnetic pole of the magnetic field generating means corresponding to the end magnetic poles is shifted, and the magnetic poles of the magnetic field generating means corresponding to the end magnetic poles are As polar, a process cartridge, characterized in that to form a forward field of virtually NS and induced causes the reverse polarity magnetic poles of the portion facing the end portion magnetic pole of said magnetic field generating means.

【００２７】本発明による他の態様によれば、画像形成
装置本体に着脱可能なプロセスカートリッジにおいて、
少なくとも電子写真感光体と、現像装置とを有し、前記
現像装置は、磁性現像剤を収容する現像容器と、該現像
容器に回転自在に支持され、内部に磁界発生手段を固定
配置することにより磁性現像剤を担持搬送する現像剤担
持体とを有し、前記現像剤担持体の両端部に、前記現像
剤担持体の外周面と所定間隙をもって磁石シール部材を
配置し、前記磁石シール部材の前記現像剤担持体と対向
する領域の現像剤搬送方向出口側の部位に出口側磁極を
配置し、前記出口側磁極よりも前記現像剤担持体移動方
向下流側に前記磁界発生手段の磁極を配置し、前記磁界
発生手段の磁極と前記磁石シール部材の前記出口側磁極
とを同極性として、前記磁界発生手段の前記出口側磁極
と対向する部位に逆極性の磁極を誘起させて仮想的にＮ
Ｓの順磁界を形成させることを特徴とするプロセスカー
トリッジが提供される。According to another aspect of the present invention, in a process cartridge detachable from an image forming apparatus main body,
At least an electrophotographic photoreceptor and a developing device, wherein the developing device is provided with a developing container for containing a magnetic developer, a rotatable support for the developing container, and a magnetic field generating means fixedly disposed inside. A developer carrying member that carries and transports the magnetic developer, and a magnet sealing member is disposed at both ends of the developer carrying member with a predetermined gap from the outer peripheral surface of the developer carrying member. An exit-side magnetic pole is arranged at a region on the exit side in the developer conveyance direction in a region opposed to the developer carrying member, and a magnetic pole of the magnetic field generating means is arranged on the downstream side of the exit-side magnetic pole in the developer carrying direction. The magnetic pole of the magnetic field generating means and the outlet magnetic pole of the magnet seal member have the same polarity, and a magnetic pole of the opposite polarity is induced at a portion of the magnetic field generating means facing the outlet magnetic pole, thereby virtually setting N.
A process cartridge characterized by forming a forward magnetic field of S is provided.

【００２８】また、本発明による他の態様によれば、画
像形成装置本体に着脱可能なプロセスカートリッジにお
いて、少なくとも電子写真感光体と、現像装置とを有
し、前記現像装置は、磁性現像剤を収容する現像容器
と、該現像容器に回転自在に支持され、内部に磁界発生
手段を固定配置することにより磁性現像剤を担持搬送す
る現像剤担持体とを有し、前記現像剤担持体の両端部
に、前記現像剤担持体の外周面と所定間隙をもって磁石
シール部材を配置し、前記磁石シール部材の前記現像剤
担持体と対向する領域の現像剤搬送方向入口側の部位に
入口側磁極を配置し、前記出口側磁極よりも前記現像剤
担持体移動方向上流側に前記磁界発生手段の磁極を配置
し、前記磁界発生手段の磁極と前記磁石シール部材の入
口側磁極を同極性として、前記磁界発生手段の前記入口
側磁極と対向する部位に逆極性の磁極を誘起させて仮想
的にＮＳの順磁界を形成させることを特徴とするプロセ
スカートリッジが提供される。According to another aspect of the present invention, a process cartridge detachable from an image forming apparatus main body includes at least an electrophotographic photosensitive member and a developing device, wherein the developing device uses a magnetic developer. A developer container that accommodates the developer container, and a developer carrier that is rotatably supported by the developer container and that carries and transports the magnetic developer by fixedly disposing a magnetic field generating means inside the developer container. In the portion, a magnet seal member is arranged with a predetermined gap from the outer peripheral surface of the developer carrying member, and an entrance side magnetic pole is provided at a portion of the magnet sealing member facing the developer carrying member on the entrance side in the developer transport direction. The magnetic pole of the magnetic field generating means is arranged on the upstream side of the developer carrier moving direction from the outlet magnetic pole, and the magnetic pole of the magnetic field generating means and the inlet magnetic pole of the magnet seal member are of the same polarity. A process cartridge, characterized in that to form a forward field of virtually NS and induced causes the reverse polarity magnetic poles of said inlet-side magnetic pole facing the portion of the magnetic field generating means.

【００２９】更に、本発明による他の態様によれば、少
なくとも電子写真感光体と現像装置を含むプロセスカー
トリッジを着脱可能な画像形成装置において、前記現像
装置は、磁性現像剤を収容する現像容器と、該現像容器
に回転自在に支持され、複数の磁極を備えた磁界発生手
段を内部に固定配置することにより磁性現像剤を担持搬
送する現像剤担持体と、前記現像剤担持体の両端部にそ
の外周面と所定間隙をもって配置された複数の磁極を備
えた磁石シール部材と、を有し、前記磁石シール部材
は、前記磁石シール部材の前記現像剤担持体移動方向端
部の端部磁極と、前記端部磁極と対応する前記磁界発生
手段の少なくとも一つの前記磁極とがずれるように配置
され、前記端部磁極と対応する前記磁界発生手段の前記
磁極とを同極性として、前記磁界発生手段の前記端部磁
極と対向する部位に逆極性の磁極を誘起させて仮想的に
ＮＳの順磁界を形成させることを特徴とする画像形成装
置が提供される。Further, according to another aspect of the present invention, in an image forming apparatus in which a process cartridge including at least an electrophotographic photosensitive member and a developing device is detachable, the developing device includes a developing container containing a magnetic developer. A developer carrier rotatably supported by the developer container and carrying a magnetic developer by fixedly disposing magnetic field generating means having a plurality of magnetic poles therein, and at both ends of the developer carrier. A magnet seal member having a plurality of magnetic poles arranged at a predetermined gap from the outer peripheral surface thereof, wherein the magnet seal member has an end magnetic pole at an end of the developer carrying member moving direction of the magnet seal member. The at least one magnetic pole of the magnetic field generating means corresponding to the end magnetic pole is disposed so as to be displaced, and the end magnetic pole and the magnetic pole of the magnetic field generating means corresponding to the end magnetic pole have the same polarity. , The image forming apparatus is provided, characterized in that to form a forward field of the end magnetic pole facing virtually by inducing a reverse polarity magnetic poles of the sites NS of the magnetic field generating means.

【００３０】また、本発明による他の態様によれば、少
なくとも電子写真感光体と現像装置とを含むプロセスカ
ートリッジを着脱可能な画像形成装置において、前記現
像装置は、磁性現像剤を収容する現像容器と、該現像容
器に回転自在に支持され、内部に磁界発生手段を固定配
置することにより磁性現像剤を担持搬送する現像剤担持
体とを有し、前記現像剤担持体の両端部に、前記現像剤
担持体の外周面と所定間隙をもって磁石シール部材を配
置し、前記磁石シール部材の前記現像剤担持体と対向す
る領域の現像剤搬送方向出口側の部位に出口側磁極を配
置し、前記出口側磁極よりも前記現像剤担持体移動方向
下流側に前記磁界発生手段の磁極を配置し、前記磁界発
生手段の磁極と前記磁石シール部材の前記出口側磁極と
を同極性として、前記磁界発生手段の前記出口側磁極と
対向する部位に逆極性の磁極を誘起させて仮想的にＮＳ
の順磁界を形成させることを特徴とする画像形成装置が
提供される。According to another aspect of the present invention, there is provided an image forming apparatus in which a process cartridge including at least an electrophotographic photosensitive member and a developing device is detachably mountable, wherein the developing device includes a developing container containing a magnetic developer. And a developer carrier rotatably supported by the developing container, and carrying a magnetic developer by fixedly disposing a magnetic field generating means inside, and at both ends of the developer carrier, A magnet seal member is arranged with a predetermined gap from the outer peripheral surface of the developer carrying member, and an exit side magnetic pole is arranged at a portion of the magnet sealing member facing the developer carrying member on an exit side in a developer conveying direction; A magnetic pole of the magnetic field generating means is arranged on the downstream side in the developer carrier moving direction from an outlet side magnetic pole, and the magnetic pole of the magnetic field generating means and the outlet side magnetic pole of the magnet seal member have the same polarity, Serial and induced causes the reverse polarity magnetic poles of the outlet side magnetic pole opposed to the site of the magnetic field generating means virtually NS
An image forming apparatus is provided which forms a forward magnetic field.

【００３１】更に、本発明による他の態様によれば、少
なくとも電子写真感光体と現像装置とを含むプロセスカ
ートリッジを着脱可能な画像形成装置において、前記現
像装置は、磁性現像剤を収容する現像容器と、該現像容
器に回転自在に支持され、内部に磁界発生手段を固定配
置することにより磁性現像剤を担持搬送する現像剤担持
体とを有し、前記現像剤担持体の両端部に、前記現像剤
担持体の外周面と所定間隙をもって磁石シール部材を配
置し、前記磁石シール部材の前記現像剤担持体と対向す
る領域の現像剤搬送方向入口側の部位に入口側磁極を配
置し、前記出口側磁極よりも前記現像剤担持体移動方向
上流側に前記磁界発生手段の磁極を配置し、前記磁界発
生手段の磁極と前記磁石シール部材の入口側磁極を同極
性として、前記磁界発生手段の前記入口側磁極と対向す
る部位に逆極性の磁極を誘起させて仮想的にＮＳの順磁
界を形成させることを特徴とする画像形成装置が提供さ
れる。Further, according to another aspect of the present invention, in an image forming apparatus in which a process cartridge including at least an electrophotographic photosensitive member and a developing device is detachable, the developing device includes a developing container containing a magnetic developer. And a developer carrier rotatably supported by the developing container, and carrying a magnetic developer by fixedly disposing a magnetic field generating means inside, and at both ends of the developer carrier, A magnet seal member is arranged with a predetermined gap from the outer peripheral surface of the developer carrier, and an entrance-side magnetic pole is arranged at a portion of the magnet seal member facing the developer carrier on an entrance side in a developer transport direction, The magnetic pole of the magnetic field generating means is arranged on the upstream side in the developer carrier moving direction from the outlet magnetic pole, and the magnetic pole of the magnetic field generating means and the inlet magnetic pole of the magnet seal member have the same polarity. Image forming apparatus is provided for causing it induced was the reverse polarity magnetic poles of the portion facing said inlet side magnetic pole generating means to form a forward field of virtually NS.

【００３２】上記発明によれば、前記磁界発生手段は表
面が着磁された複数の磁石ブロックと前記複数の磁石ブ
ロックの間を占める磁性部材とを含むことが好ましい。According to the above invention, it is preferable that the magnetic field generating means includes a plurality of magnet blocks whose surfaces are magnetized and a magnetic member occupying a space between the plurality of magnet blocks.

【００３３】[0033]

【発明の実施の形態】以下、本発明に係る現像装置、プ
ロセスカートリッジおよび画像形成装置を図面に則して
更に詳しく説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a developing device, a process cartridge and an image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

【００３４】実施例１ 本発明の第１実施例として電子写真プロセスを利用した
プロセスカートリッジ着脱方式の画像形成装置であるレ
ーザービームプリンタについて図１により説明する。Embodiment 1 As a first embodiment of the present invention, a laser beam printer which is an image forming apparatus of a process cartridge detachable type utilizing an electrophotographic process will be described with reference to FIG.

【００３５】このレーザービームプリンタは、像担持体
としての回転感光ドラム型電子写真感光体（以下、「感
光ドラム」ともいう）１を有し、感光ドラム１は矢印ａ
方向に回転駆動される。感光ドラム１の周囲には、帯電
装置２、現像装置３、転写手段４およびクリーニング装
置６が配設されている。This laser beam printer has a rotating photosensitive drum type electrophotographic photosensitive member (hereinafter also referred to as "photosensitive drum") 1 as an image carrier, and the photosensitive drum 1 has an arrow a
It is driven to rotate in the direction. Around the photosensitive drum 1, a charging device 2, a developing device 3, a transfer unit 4, and a cleaning device 6 are provided.

【００３６】感光ドラム１は、帯電装置２によって均一
に帯電された後、画像情報信号に対応して画像露光装置
５からのレーザー光Ｅにより画像露光が行われて、感光
ドラム１上に静電潜像が形成され、現像装置３によって
静電潜像が顕画像として現像される。この顕画像は転写
手段としての転写ローラ４により転写部で静電気力と押
圧力にて転写材Ｐに転写され、熱定着方式などの定着装
置９へ搬送されて、転写材Ｐ上の顕画像が定着され、画
像形成物（プリント、コピー）として装置外へ排出され
る。After the photosensitive drum 1 is uniformly charged by the charging device 2, the photosensitive drum 1 is exposed to an image by laser light E from the image exposing device 5 in accordance with the image information signal. A latent image is formed, and the developing device 3 develops the electrostatic latent image as a visible image. This visible image is transferred to the transfer material P by a transfer roller 4 as a transfer unit at a transfer portion by an electrostatic force and a pressing force, and is conveyed to a fixing device 9 such as a thermal fixing method, where the visible image on the transfer material P is transferred. The image is fixed and discharged out of the apparatus as an image formed product (print, copy).

【００３７】また、転写材Ｐに対するトナー画像転写後
の感光ドラム面はクリーニング装置６により残留トナー
などの付着汚染物が除去、清掃され繰り返して作像に供
される。After the transfer of the toner image to the transfer material P, the cleaning device 6 removes and cleans the adhered contaminants such as residual toner, and repeatedly performs image formation.

【００３８】本実施例では、感光ドラム１、帯電装置
２、現像装置３、およびクリーニング装置６の４つのプ
ロセス手段がプロセスカートリッジＣとして一体的にカ
ートリッジハウジング１０の所定位置に組み込まれ、画
像形成装置本体に装着手段であるプロセスカートリッジ
挿脱案内兼保持部８により着脱交換自在に装着される。In this embodiment, the four process means of the photosensitive drum 1, the charging device 2, the developing device 3, and the cleaning device 6 are integrally incorporated at a predetermined position of the cartridge housing 10 as the process cartridge C, and the image forming apparatus It is detachably mounted on the main body by a process cartridge insertion / removal guide / holding unit 8 as mounting means.

【００３９】プロセスカートリッジＣが画像形成装置本
体に対して所定位置に装着した状態において、プロセス
カートリッジＣ側と画像形成装置本体側とが機械的かつ
電気的に相互カップリング状態となり、またプロセスカ
ートリッジＣ側の感光ドラム１の下面には画像形成装置
本体側の転写ローラ４が所定の当接状態となり、画像形
成が実行可能状態となる。When the process cartridge C is mounted at a predetermined position with respect to the image forming apparatus main body, the process cartridge C side and the image forming apparatus main body side are mechanically and electrically coupled to each other. The transfer roller 4 on the image forming apparatus main body side is brought into a predetermined contact state with the lower surface of the photosensitive drum 1 on the side, so that image formation is possible.

【００４０】なお、プロセスカートリッジは上記の構成
に限られるものではなく、帯電手段、現像手段またはク
リーニング手段と、電子写真感光体とを一体的にカート
リッジ化し、画像形成装置本体に対して着脱可能とした
もの、あるいは、帯電手段、現像手段、クリーニング手
段の少なくとも１つと電子写真感光体とを一体的にカー
トリッジ化し、画像形成装置本体に着脱可能としたも
の、更には、少なくとも現像手段と電子写真感光体とを
一体的にカートリッジ化し、画像形成装置本体に着脱可
能としたものが含まれる。The process cartridge is not limited to the above-described configuration, and the charging unit, the developing unit or the cleaning unit, and the electrophotographic photosensitive member are integrally formed into a cartridge, and the process cartridge is detachable from the image forming apparatus main body. Or a cartridge in which at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge and can be attached to and detached from an image forming apparatus main body. It includes a body integrally formed as a cartridge and detachable from the image forming apparatus main body.

【００４１】つぎに、現像装置３について図２〜図７を
参照して説明する。Next, the developing device 3 will be described with reference to FIGS.

【００４２】図２に概略的に示された現像装置３は、磁
性現像剤としての磁性トナーＴを収納した現像容器３０
を有し、感光ドラム１に面した開口部には現像剤担持体
としてのアルミニウム、ステンレス鋼などの非磁性円筒
体（以下、「現像スリーブ」という）３１が感光ドラム
１に対して平行に配置されている。現像スリーブ３１は
その内部にローラ状の磁界発生手段である磁石（以下、
「磁石ローラ」という）３２が固定配置され、スリーブ
軸受（不図示）を介して現像容器３０に回転可能に取り
付けられている。The developing device 3 schematically shown in FIG. 2 includes a developing container 30 containing a magnetic toner T as a magnetic developer.
A non-magnetic cylindrical body (hereinafter referred to as a “developing sleeve”) 31 made of aluminum, stainless steel, or the like as a developer carrier is disposed in parallel with the photosensitive drum 1 at an opening facing the photosensitive drum 1. Have been. The developing sleeve 31 has a magnet (hereinafter, referred to as a roller-shaped magnetic field generating means) inside thereof.
A “magnet roller” 32 is fixedly disposed, and is rotatably attached to the developing container 30 via a sleeve bearing (not shown).

【００４３】本実施例では、磁石ローラ３２は図示のご
とくその周面に２つのＮ極Ｎ１、Ｎ２、および２つのＳ
極Ｓ１、Ｓ２を有している。更に説明すると、磁石ロー
ラ３２は、表面が着磁された磁石ブロック３２ａと磁性
部材３２ｂとから構成され、磁石ブロック３２ａは４つ
の小磁石ブロック３２ａ１、３２ａ２、３２ａ３、３２
ａ４からなり、交互にＮ極とＳ極が配置され、おのおの
Ｎ１極、Ｓ１極、Ｎ２極、Ｓ２極とされている。図３に
示すように、磁性部材３２ｂには４つの凹部３２ｂ１、
３２ｂ２、３２ｂ３、３２ｂ４が設けられており、おの
おの磁石ブロック３２ａ１、３２ａ２、３２ａ３、３２
ａ４を位置決めしている。磁石ブロック３２ａはこのよ
うな簡単な構成で位置決めされている。In this embodiment, the magnet roller 32 has two north poles N1, N2 and two S poles on its peripheral surface as shown in the figure.
It has poles S1 and S2. More specifically, the magnet roller 32 includes a magnet block 32a whose surface is magnetized and a magnetic member 32b. The magnet block 32a is composed of four small magnet blocks 32a1, 32a2, 32a3, and 32.
a4, N poles and S poles are alternately arranged, and are respectively N1 pole, S1 pole, N2 pole, and S2 pole. As shown in FIG. 3, the magnetic member 32b has four concave portions 32b1,
32b2, 32b3, 32b4 are provided, and the magnet blocks 32a1, 32a2, 32a3, 32 are respectively provided.
a4 is positioned. The magnet block 32a is positioned with such a simple configuration.

【００４４】現像スリーブ３１は、矢印にて示す反時計
方向に回転して、現像容器３０内の領域Ａで供給された
磁性トナーＴを磁石ローラ３２の磁力により表面に付着
させ、現像スリーブ３１との摩擦により電荷を付与しな
がら搬送する。The developing sleeve 31 rotates in the counterclockwise direction indicated by the arrow, and the magnetic toner T supplied in the area A in the developing container 30 adheres to the surface by the magnetic force of the magnet roller 32. The transfer is performed while applying a charge by the friction of.

【００４５】現像剤層厚規制手段としての規制ブレード
（弾性ブレード）３３が、現像容器３０の出口において
Ｎ２極の存在下で現像スリーブ３１を押圧して、現像ス
リーブ３１が現像領域に担持搬送する現像剤層の厚みを
規制する。A regulating blade (elastic blade) 33 as a developer layer thickness regulating means presses the developing sleeve 31 at the outlet of the developing container 30 in the presence of the N2 pole, and the developing sleeve 31 is carried and conveyed to the developing area. Regulate the thickness of the developer layer.

【００４６】現像スリーブ３１によって担持搬送された
磁性トナーＴは現像磁極Ｓ１のある現像領域において矢
印方向に移動する感光ドラム１に形成された潜像を可視
化する。このとき現像スリーブ３１には電源Ｐ２から交
流電圧に直流電圧を重畳した振動バイアス電圧が印加さ
れる。なお、振動バイアス電圧の波形としては矩形波、
サイン波などが使用できる。The magnetic toner T carried and transported by the developing sleeve 31 visualizes a latent image formed on the photosensitive drum 1 moving in the direction of the arrow in a developing area where the developing magnetic pole S1 exists. At this time, a vibration bias voltage in which a DC voltage is superimposed on an AC voltage is applied to the developing sleeve 31 from the power supply P2. Note that the waveform of the oscillation bias voltage is a rectangular wave,
Sine waves and the like can be used.

【００４７】現像された後の残存トナーＴは、現像容器
３０の入口の取り込み極Ｎ１において現像容器３０内へ
回収され、汲み上げ極Ｓ２を経て現像容器３０内の磁性
トナーと撹拌混合される。The residual toner T after the development is recovered into the developing container 30 at the take-in pole N1 at the entrance of the developing vessel 30, and is stirred and mixed with the magnetic toner in the developing vessel 30 via the pumping pole S2.

【００４８】図４〜図６に示すように、現像スリーブ３
１の両端部には磁石シール部材３４が現像スリーブ３１
の外周面と間隙ｇを隔てて配置され、現像容器３０に取
り付けられている。As shown in FIGS. 4 to 6, the developing sleeve 3
A magnet seal member 34 is provided at both ends of the developing sleeve 31.
And is attached to the developing container 30 with a gap g from the outer peripheral surface.

【００４９】また、図７に示すように、磁石シール部材
３４の内周面にはＮＳ極が多磁極に着磁されている。具
体的には、３つのＳ極Ｓ１１、Ｓ１２、Ｓ１３と、３つ
のＮ極Ｎ１１、Ｎ１２、Ｎ１３を有している。As shown in FIG. 7, an NS pole is magnetized into multiple magnetic poles on the inner peripheral surface of the magnet seal member 34. Specifically, it has three south poles S11, S12, and S13 and three north poles N11, N12, and N13.

【００５０】図４に示すように、この磁石シール部材３
４の出口側の磁極Ｎ１３と対向する現像スリーブ３１内
部には磁性部材３２ｂが配設され、その下流側に磁石ブ
ロック３２ａの規制極Ｎ２が配設されている。As shown in FIG. 4, this magnet seal member 3
A magnetic member 32b is disposed inside the developing sleeve 31 facing the magnetic pole N13 on the exit side of the nozzle 4, and a regulating pole N2 of the magnet block 32a is disposed downstream of the magnetic member 32b.

【００５１】更に、図８により詳しく説明すると、磁石
ローラ３２の規制極Ｎ２の上流側に磁石シール部材３４
の出口側の磁極Ｎ１３を配置しており、この磁極Ｎ１３
と対向する現像スリーブ３１内部の磁性部材３２ｂに逆
極性の磁極（Ｓ極）を誘起させている。また、誘起され
た磁極（Ｓ極）の近くに規制極Ｎ２を配置しているの
で、この部分で逆極性の磁極（Ｓ極）がより誘起され易
くなっている。この誘起された磁極（Ｓ極）と磁極Ｎ１
３とで仮想的にＮＳ順磁界を形成し、この間で磁力線が
集中している、従って、磁力線によるシールド効果によ
り現像剤のもれをより効果的に抑制・防止することがで
きる。つまり、ユーザーがプロセスカートリッジ取り扱
い時に衝撃などを与えてもより効果的に現像剤のもれを
抑制・防止することができる。8, the magnet seal member 34 is provided upstream of the regulating pole N2 of the magnet roller 32.
The magnetic pole N13 on the exit side of the magnetic pole N13 is disposed.
A magnetic pole (S pole) of the opposite polarity is induced in the magnetic member 32b inside the developing sleeve 31 opposite to the above. Further, since the regulating pole N2 is arranged near the induced magnetic pole (S pole), a magnetic pole of the opposite polarity (S pole) is more easily induced at this portion. The induced magnetic pole (S pole) and magnetic pole N1
3, the NS forward magnetic field is virtually formed, and the lines of magnetic force are concentrated between them. Therefore, the leakage of the developer can be more effectively suppressed and prevented by the shielding effect of the lines of magnetic force. That is, even if the user gives an impact when handling the process cartridge, the leakage of the developer can be more effectively suppressed and prevented.

【００５２】また、この磁石シール性部材３４は内周面
をＮＳ極の多磁極に着磁しているので、磁石シール部材
３４の磁界の作用により、磁石シール部材３４の内周面
全域で磁気ブラシの穂立ちを形成できるので、良好なシ
ール性を発揮することができ、現像剤のすり抜けや衝撃
に対する現像剤もれなどを抑制・防止することができ
る。Further, since the inner peripheral surface of the magnet seal member 34 is magnetized to the multi-pole of the NS pole, the magnetic field of the magnet seal member 34 causes the entire inner peripheral surface of the magnet seal member 34 to be magnetic. Since the brush ears can be formed, good sealing properties can be exhibited, and it is possible to suppress and prevent the developer from slipping through the developer or leaking from the impact.

【００５３】図９には現像装置端部の磁石シール部材お
よび型枠を説明するための模式図が示される。FIG. 9 is a schematic diagram for explaining the magnet seal member and the mold at the end of the developing device.

【００５４】同図において、磁石シール部材３４を取り
付けるための型枠３５は磁石シール部材３４を取り付け
るための位置決め部分３５ａ、３５ｂを有しており、第
１位置決め部分３５ａは規制ブレード取り付け用の型枠
を利用して、これと一体化して構成されており、磁石シ
ール部材３４の直線部分の位置決めを行い、第２位置決
め部分３５ｂは磁石シール部材３４の円弧状部分の位置
決めを行っている。取り付け方法としては、まず、磁石
シール部材３４を円弧状の第２位置決め部３５ｂに押し
当て、直線状の第１位置決め部３５ａ側からビス４０で
固定している。In the figure, a mold 35 for mounting the magnet seal member 34 has positioning portions 35a and 35b for mounting the magnet seal member 34, and the first positioning portion 35a is a mold for mounting the regulating blade. It is configured integrally with the frame using a frame, and positions the linear portion of the magnet seal member 34, and the second positioning portion 35b positions the arc-shaped portion of the magnet seal member 34. As a mounting method, first, the magnet seal member 34 is pressed against the arc-shaped second positioning portion 35b, and is fixed with the screw 40 from the linear first positioning portion 35a side.

【００５５】このように型枠３５の形状が簡素であり、
規制ブレード取り付け用の型枠と同一面の箇所に形成し
ているので、型枠の肉厚を薄くすることなく容易に作製
することができる。また、磁石シール部材３４の形状を
過度に大きくしなくてもよいので、コストを低くするこ
とができる。また、配置スペースを小さくできるので、
他の部材の配置上の制約を受けなくてよく、装置構成の
自由度を向上させることができる。As described above, the shape of the mold 35 is simple,
Since it is formed on the same surface as the mold for attaching the regulating blade, it can be easily manufactured without reducing the thickness of the mold. Further, since the shape of the magnet seal member 34 need not be excessively large, the cost can be reduced. Also, since the placement space can be reduced,
There is no need to restrict the arrangement of other members, and the degree of freedom of the device configuration can be improved.

【００５６】以上説明したように、現像スリーブの両端
部に磁石シール部材を配置して、現像スリーブ長手方向
への現像剤のすり抜けおよび衝撃などによって生じる現
像剤もれを抑制・防止しながら、この磁石シール部材の
磁石を利用して、すなわち、磁石部材の出口側に磁極を
設け、この出口側の磁極よりも下流側に磁石ローラの磁
極を同極性として配置し、この磁石部材の磁極と対向す
る現像スリーブ内部に逆極性の磁極を誘起させて仮想的
にＮＳの順磁界を形成させることにより、簡単な構成
で、現像剤のすり抜けおよび衝撃などによって生じる現
像剤もれを抑制・防止しながら、装置を簡素化すること
ができ、低コストを達成できる。また、装置構成の自由
度を向上させることができる。As described above, the magnet seal members are arranged at both ends of the developing sleeve to suppress and prevent the leakage of the developer caused by the passage of the developer in the longitudinal direction of the developing sleeve and the impact, and the like. Utilizing the magnet of the magnet seal member, that is, a magnetic pole is provided on the outlet side of the magnet member, and the magnetic pole of the magnet roller is arranged with the same polarity downstream of the magnetic pole on the outlet side, facing the magnetic pole of this magnet member By inducing a magnetic pole of reverse polarity inside the developing sleeve to form a virtual forward magnetic field of NS, it is possible to suppress and prevent developer leakage caused by developer slip-through and impact with a simple configuration. Thus, the apparatus can be simplified and low cost can be achieved. Further, the degree of freedom of the device configuration can be improved.

【００５７】つぎに、本実施例における数値的具体例に
ついて説明する。Next, a numerical example in this embodiment will be described.

【００５８】本実施例では、感光ドラム１は周速が９４
ｍｍ／ｓｅｃ、外径が３０ｍｍ、現像スリーブ３１は周
速が１１１ｍｍ／ｓｅｃ、外径が１６ｍｍである。現像
スリーブ３１の回転方向は感光ドラム１に対して順方向
とした。また、感光ドラム１と現像スリーブ３１との間
隔ｈは０．３ｍｍとした。このとき、現像スリーブ３１
内に固定する磁石ローラ３２の各磁極の現像スリーブ表
面上での、現像スリーブ表面に対する法線方向の磁束密
度のピーク値は４００〜９００×１０-4Ｔ（テスラ）で
あった。磁石シール部材３４は、Ｎｄ−Ｆｅ−Ｂの磁性
粉末を含有するナイロンバインダーを備えた幅ｄ＝４ｍ
ｍの射出成形品である。磁石シール部材３４と現像スリ
ーブ３１との間隙ｇは０．１〜０．７ｍｍとした。In this embodiment, the photosensitive drum 1 has a peripheral speed of 94.
mm / sec, the outer diameter is 30 mm, and the peripheral speed of the developing sleeve 31 is 111 mm / sec, and the outer diameter is 16 mm. The rotation direction of the developing sleeve 31 was set to the forward direction with respect to the photosensitive drum 1. The distance h between the photosensitive drum 1 and the developing sleeve 31 was 0.3 mm. At this time, the developing sleeve 31
The peak value of the magnetic flux density in the direction normal to the surface of the developing sleeve on the surface of the developing sleeve of each magnetic pole of the magnet roller 32 fixed therein was 400 to 900 × 10 −4 T (tesla). The magnet seal member 34 has a width d = 4 m provided with a nylon binder containing Nd-Fe-B magnetic powder.
m. The gap g between the magnet seal member 34 and the developing sleeve 31 was 0.1 to 0.7 mm.

【００５９】このとき、磁石シール部材３４の各磁極の
現像スリーブ表面上での、現像スリーブ表面に対する法
線方向の磁束密度のピーク値は１０００〜２２００×１
０-4Ｔ（テスラ）であった。At this time, the peak value of the magnetic flux density on the surface of the developing sleeve of each magnetic pole of the magnet seal member 34 in the direction normal to the surface of the developing sleeve is 1000 to 2200 × 1.
0 -4 T (tesla).

【００６０】以上のように、本実施例よれば、簡単な構
成で、現像スリーブ長手方向への現像剤のすり抜けや衝
撃などによって生じる現像剤もれを抑制・防止しなが
ら、画質を良好にでき、プリント枚数を増やすことがで
きる。また、ユーザーによってプロセスカートリッジを
画像形成装置に対して着脱する際の衝撃などを加えられ
てももれることのない良好なシール性が得られる。As described above, according to the present embodiment, it is possible to improve the image quality with a simple structure while suppressing and preventing the developer leakage caused by the slip-through or impact of the developer in the longitudinal direction of the developing sleeve. , The number of prints can be increased. In addition, a good sealing property that does not leak even when an impact or the like when the process cartridge is attached to or detached from the image forming apparatus by a user can be obtained.

【００６１】比較例１ つぎに、第１比較例について図１０と図１１により説明
する。本比較例は、第１実施例とは磁石シール部材３４
と現像容器３０の構成が若干異なっている。Comparative Example 1 Next, a first comparative example will be described with reference to FIGS. This comparative example is different from the first embodiment in that the magnet seal member 34 is used.
And the configuration of the developing container 30 are slightly different.

【００６２】第１実施例では、磁石シール部材３４を磁
石ローラ３２の磁極Ｎ２まで覆うことなく配設していた
が、本比較例では、磁石シール部材４３４を磁石ローラ
３２の磁極Ｎ２まで覆うように配設した構成になってい
る。すなわち、本比較例では、図１０に示すように、磁
石ローラ３２の磁極Ｎ２に対向した領域まで磁石シール
部材４３４を配設し、磁石ローラ３２の磁極Ｎ２には磁
石シール部材４３４の磁極Ｓ１５が対向している。この
ため、図１１に示すように、磁石シール部材４３４を取
り付けるための型枠４３５の形状が複雑になり、更に磁
石シール部材４３４の形状が大きくなるため、コストが
高くなる。また型枠４３５の突起部４３５ａの配置され
ている個所には他の部材を配置できないという制約があ
る。In the first embodiment, the magnet seal member 34 is disposed without covering the magnetic pole N2 of the magnet roller 32. In this comparative example, the magnet seal member 434 is arranged so as to cover the magnetic pole N2 of the magnet roller 32. It is configured to be arranged in. That is, in this comparative example, as shown in FIG. 10, the magnet seal member 434 is disposed up to the region facing the magnetic pole N2 of the magnet roller 32, and the magnetic pole S15 of the magnet seal member 434 is provided at the magnetic pole N2 of the magnet roller 32. Are facing each other. Therefore, as shown in FIG. 11, the shape of the mold 435 for attaching the magnet seal member 434 becomes complicated, and the shape of the magnet seal member 434 becomes large, so that the cost increases. In addition, there is a restriction that no other member can be arranged at the position where the protrusion 435a of the mold 435 is arranged.

【００６３】実施例２ つぎに、本発明の第２実施例について図１２と図１３に
より説明する。本実施例は、第１実施例とは磁石ローラ
３２の磁極構成と磁石シール部材３４の構成が若干異な
っている他は同様である。Embodiment 2 Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is the same as the first embodiment except that the magnetic pole configuration of the magnet roller 32 and the configuration of the magnet seal member 34 are slightly different.

【００６４】すなわち、第１実施例では、現像磁極Ｓ１
が感光ドラム１と略対向配置されていたが、本実施例
は、現像部において磁極Ｓ１と磁極Ｎ１による極間を感
光ドラム１と対向配置させた構成となっている。That is, in the first embodiment, the developing magnetic pole S1
Is substantially opposed to the photosensitive drum 1, but this embodiment has a configuration in which the gap between the magnetic pole S1 and the magnetic pole N1 is opposed to the photosensitive drum 1 in the developing section.

【００６５】また、第１実施例では、磁石シール部材３
４の入口側の磁極Ｓ１１と磁石ローラ３２の磁極Ｎ１と
を略対向させた構成としていたが、本実施例は、磁石シ
ール部材３４の入口側の磁極Ｎ１１とその上流側に位置
する磁石ローラ３２の磁極Ｎ１とで、磁極Ｎ１１と対向
する現像スリーブ３１内部の磁性部材３２ｂに逆極性の
磁極（Ｓ極）を誘起させる構成になっている。In the first embodiment, the magnet seal member 3
In this embodiment, the magnetic pole S11 on the inlet side of the magnet seal member 34 and the magnetic pole N1 of the magnet roller 32 are substantially opposed to each other. And a magnetic pole (S pole) of the opposite polarity is induced in the magnetic member 32b inside the developing sleeve 31 facing the magnetic pole N11.

【００６６】このような構成においても、第１実施例と
同様に現像剤のすり抜けや衝撃に対する現像剤もれなど
を抑制・防止することができる。更に、後述の第２比較
例と比較して、磁石シール部材３４を磁石ローラ３２の
磁極Ｎ１まで覆うことなく配設しているので、磁石シー
ル部材３４を感光ドラム１に接近させることなくするこ
とができる。従って、感光ドラム１を損傷することな
く、また、磁石シール部材３４の取り付け精度の許容範
囲を広げることができる。Also in such a configuration, as in the first embodiment, it is possible to suppress and prevent the developer from passing through or leaking from the developer. Further, as compared with a second comparative example described later, since the magnet seal member 34 is provided without covering up to the magnetic pole N1 of the magnet roller 32, the magnet seal member 34 does not need to approach the photosensitive drum 1. Can be. Therefore, the allowable range of the mounting accuracy of the magnet seal member 34 can be expanded without damaging the photosensitive drum 1.

【００６７】比較例２ つぎに、第２比較例について図１４により説明する。本
比較例は、第２実施例とは磁石シール部材３４と現像容
器３０の構成が若干異なっている他は同様である。Comparative Example 2 Next, a second comparative example will be described with reference to FIG. This comparative example is the same as the second example except that the configurations of the magnet seal member 34 and the developing container 30 are slightly different.

【００６８】第２実施例では、磁石シール部材３４は磁
石ローラ３２の磁極Ｎ１まで覆うことなく配設されてい
たが、本比較例は磁石シール部材３４を磁石ローラ３２
の一対の現像部下流側の磁極Ｎ１まで覆って配設した構
成になっている。In the second embodiment, the magnet seal member 34 is disposed without covering the magnetic pole N1 of the magnet roller 32. In this comparative example, the magnet seal member 34 is
Are arranged so as to cover the magnetic pole N1 on the downstream side of the pair of developing units.

【００６９】すなわち、本比較例では、図１４に示すよ
うに、現像部下流側の磁極Ｎ１に対向した領域まで磁石
シール部材３４を配設しているため、磁石シール部材３
４が感光ドラム１に極めて接近しているので、感光ドラ
ム１および現像スリーブ３１の駆動時に、磁石シール部
材３４が感光ドラム１に接触して感光ドラム１を損傷さ
せることがある。また、これを防止するために、磁石シ
ール部材の取り付け精度を極めて高精度にしなければな
らず、コストが高くなる。That is, in this comparative example, as shown in FIG. 14, since the magnet seal member 34 is disposed up to the region facing the magnetic pole N1 on the downstream side of the developing section, the magnet seal member 3
4 is very close to the photosensitive drum 1, the magnet seal member 34 may come into contact with the photosensitive drum 1 and damage the photosensitive drum 1 when the photosensitive drum 1 and the developing sleeve 31 are driven. Also, in order to prevent this, the mounting accuracy of the magnet seal member must be made extremely high, which increases the cost.

【００７０】実施例３ つぎに、本発明の第３実施例について図１５〜図１７に
より説明する。本実施例は、第１実施例とは磁石ローラ
３２の構成が若干異なっている他は第１実施例と同様の
構成である。Embodiment 3 Next, a third embodiment of the present invention will be described with reference to FIGS. This embodiment has the same configuration as the first embodiment except that the configuration of the magnet roller 32 is slightly different from the first embodiment.

【００７１】すなわち、第１実施例の磁石ローラ３２は
磁石ブロック３２ａと磁性部材３２ｂとから構成されて
いたが、本実施例の磁石ローラ１３２は、図１５と図１
６に示すように、磁石ローラ単体からなり、その周面に
４つの磁極Ｎ１、Ｎ２、Ｓ１、Ｓ２を有し、また、図１
７に示すように、磁石シール部材３４の出口側の磁極Ｎ
１３と磁石ローラ３２のＮ２極の位置がずれてＮＮの反
発磁界を形成させている。That is, the magnet roller 32 of the first embodiment is composed of the magnet block 32a and the magnetic member 32b.
As shown in FIG. 6, it is composed of a single magnet roller, and has four magnetic poles N1, N2, S1, and S2 on its peripheral surface.
As shown in FIG. 7, the magnetic pole N on the exit side of the magnet seal member 34
The position of the N2 pole of the magnet roller 32 is shifted from that of the magnet roller 13 to form a repulsive magnetic field of the NN.

【００７２】このＮＮ磁界によって、磁石シール部材３
４の出口側の磁極Ｎ１３と対向する現像スリーブ３１内
部の無着磁部に逆極性の磁極（Ｓ極）を仮想的に誘起さ
せた状態として、この磁極Ｎ１３と誘起された磁極（Ｓ
極）で仮想的にＮＳの順磁界を形成させている。従っ
て、この仮想的なＮＳの順磁界の作用により磁気ブラシ
の穂立ちを形成できるので、良好なシール性を発揮する
ことができ、現像剤のすり抜けや衝撃に対する現像剤も
れなどを抑制・防止することができる。The NN magnetic field causes the magnet seal member 3
The magnetic pole N13 and the induced magnetic pole (S pole) are set as a state in which a magnetic pole (S pole) of the opposite polarity is virtually induced in the non-magnetized portion inside the developing sleeve 31 opposed to the magnetic pole N13 on the exit side of the magnetic pole N13.
Pole) virtually forms a forward magnetic field of NS. Accordingly, since the magnetic brush can be formed by the action of the virtual forward magnetic field of the NS, a good sealing property can be exhibited, and the leakage of the developer due to the slipping of the developer or the impact can be suppressed or prevented. can do.

【００７３】なお、上記実施例では、磁性現像剤として
磁性トナーを用いる場合を例に説明したが、現像剤とし
て非磁性トナーと磁性粒子（キャリア）からなる２成分
磁性現像剤を用いても同様の効果が得られる。In the above embodiment, the case where a magnetic toner is used as the magnetic developer has been described as an example. However, the same applies when a two-component magnetic developer consisting of a non-magnetic toner and magnetic particles (carrier) is used as the developer. The effect of is obtained.

【００７４】[0074]

【発明の効果】以上の説明から明らかなように、本発明
の現像装置、プロセスカートリッジ、および画像形成装
置によれば、現像剤担持体の両端部にその外周面と所定
間隙をもって配置された複数の磁極を備えた磁石シール
部材を有し、前記磁石シール部材は、前記磁石シール部
材の前記現像剤担持体移動方向端部の端部磁極と、前記
端部磁極と対応する前記磁界発生手段の少なくとも一つ
の前記磁極とがずれるように配置され、前記端部磁極と
対応する前記磁界発生手段の前記磁極とは同極性とし
て、前記磁界発生手段の前記端部磁極と対向する部位に
逆極性の磁極を誘起させて仮想的にＮＳの順磁界を形成
させることにより、現像剤のすり抜けや衝撃に対する現
像剤もれなどを抑制・防止しながら、磁界発生手段の磁
極構成の自由度を向上させることができ、また、現像剤
のすり抜けや衝撃に対する現像剤もれなどを抑制・防止
し、現像剤の長寿命化を図りながら、装置を簡素化した
安価な構成とすることができ、更に、現像剤のすり抜け
や衝撃に対する現像剤もれなどを抑制・防止し、像担持
体が損傷することなく、また、磁石シール部材の取り付
け精度の許容範囲を大きくすることができる。As is clear from the above description, according to the developing device, the process cartridge and the image forming apparatus of the present invention, a plurality of developer carriers are disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface thereof. A magnetic seal member having a magnetic pole of the magnetic seal member, wherein the magnetic seal member has an end magnetic pole at an end of the magnet seal member in the moving direction of the developer carrier, and a magnetic field generating means corresponding to the end magnetic pole. At least one of the magnetic poles is disposed so as to be displaced, and the end magnetic pole and the magnetic pole of the magnetic field generating means corresponding to the end magnetic pole have the same polarity, and a portion of the magnetic field generating means opposite to the end magnetic pole has a reverse polarity. By inducing the magnetic poles to virtually form a forward magnetic field of NS, the degree of freedom of the magnetic pole configuration of the magnetic field generating means can be improved while suppressing and preventing the developer from passing through or leaking from the developer. In addition, it is possible to suppress and prevent the developer from leaking out or the developer leaking due to an impact, to achieve a long life of the developer, and to have a simplified and inexpensive configuration of the apparatus. Further, it is possible to suppress or prevent the developer from leaking out or the developer from leaking due to an impact, to prevent the image carrier from being damaged, and to increase the allowable range of the mounting accuracy of the magnet seal member.

【００７５】また、現像剤担持体の両端部に、前記現像
剤担持体の外周面と所定間隙をもって磁石シール部材を
配置し、前記磁石シール部材の前記現像剤担持体と対向
する領域の現像剤搬送方向出口側の部位に出口側磁極を
配置し、前記出口側磁極よりも前記現像剤担持体移動方
向下流側に前記磁界発生手段の磁極を配置し、前記磁界
発生手段の磁極と前記磁石シール部材の前記出口側磁極
とを同極性として、前記磁界発生手段の前記出口側磁極
と対向する部位に逆極性の磁極を誘起させて仮想的にＮ
Ｓの順磁界を形成させることにより、上記と同様の効果
を得ることができる。Further, a magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface of the developer carrier, and a developer is provided in a region of the magnet seal member facing the developer carrier. An outlet-side magnetic pole is disposed at a position on the outlet side in the transport direction, and a magnetic pole of the magnetic field generating unit is disposed downstream of the outlet-side magnetic pole in the direction of movement of the developer carrier, and a magnetic pole of the magnetic field generating unit and the magnet seal are disposed. The exit side magnetic pole of the member is made to have the same polarity, and a magnetic pole of the opposite polarity is induced at a portion of the magnetic field generating means opposite to the exit side magnetic pole, thereby virtually setting the N pole.
The same effect as described above can be obtained by forming a forward magnetic field of S.

【００７６】更に、現像剤担持体の両端部に、前記現像
剤担持体の外周面と所定間隙をもって磁石シール部材を
配置し、前記磁石シール部材の前記現像剤担持体と対向
する領域の現像剤搬送方向入口側の部位に入口側磁極を
配置し、前記出口側磁極よりも前記現像剤担持体移動方
向上流側に前記磁界発生手段の磁極を配置し、前記磁界
発生手段の磁極と前記磁石シール部材の入口側磁極を同
極性として、前記磁界発生手段の前記入口側磁極と対向
する部位に逆極性の磁極を誘起させて仮想的にＮＳの順
磁界を形成させることにより、上記と同様の効果を得る
ことができる。Further, a magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface of the developer carrier, and a developer is provided in a region of the magnet seal member facing the developer carrier. An inlet-side magnetic pole is disposed at a portion on the inlet side in the transport direction, and a magnetic pole of the magnetic field generating unit is disposed upstream of the outlet-side magnetic pole in the direction of movement of the developer carrier, and a magnetic pole of the magnetic field generating unit and the magnet seal are disposed. The same effect as described above can be obtained by causing the magnetic pole of the member to have the same polarity on the inlet side and inducing a magnetic pole of the opposite polarity at a portion of the magnetic field generating means facing the magnetic pole on the inlet side to virtually form a forward magnetic field of NS. Can be obtained.

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

【図１】第１〜第３実施例に係る画像形成装置を示す概
略構成図である。FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to first to third embodiments.

【図２】第１実施例における現像スリーブの磁石ローラ
を示す説明図である。FIG. 2 is an explanatory view showing a magnet roller of a developing sleeve in the first embodiment.

【図３】第１実施例における磁石ローラの磁性部材を示
す説明図である。FIG. 3 is an explanatory view showing a magnetic member of the magnet roller in the first embodiment.

【図４】第１実施例における磁石ローラと磁石シール部
材を示す説明図である。FIG. 4 is an explanatory view showing a magnet roller and a magnet seal member in the first embodiment.

【図５】第１実施例における磁石ローラと磁石シール部
材を示す斜視図である。FIG. 5 is a perspective view showing a magnet roller and a magnet sealing member in the first embodiment.

【図６】第１実施例における現像スリーブの端部支持構
造を示す断面図である。FIG. 6 is a cross-sectional view illustrating an end support structure of a developing sleeve according to the first embodiment.

【図７】第１実施例における磁石シール部材の着磁パタ
ーンを示す斜視図である。FIG. 7 is a perspective view showing a magnetization pattern of the magnet seal member in the first embodiment.

【図８】第１実施例における磁石シール部材の磁極およ
び磁石ローラの磁極からの磁力線を示す説明図である。FIG. 8 is an explanatory diagram showing magnetic lines of force from a magnetic pole of a magnet seal member and a magnetic pole of a magnet roller in the first embodiment.

【図９】第１実施例における磁石シール部材取付時の型
枠を示す説明図である。FIG. 9 is an explanatory view showing a mold when a magnet seal member is attached in the first embodiment.

【図１０】第１比較例における磁石ローラと磁石シール
部材を示す説明図である。FIG. 10 is an explanatory diagram showing a magnet roller and a magnet seal member in a first comparative example.

【図１１】第１比較例における磁石シール部材取付時の
型枠を示す説明図である。FIG. 11 is an explanatory diagram showing a mold when a magnet seal member is attached in the first comparative example.

【図１２】第２実施例における現像スリーブの磁石ロー
ラを示す説明図である。FIG. 12 is an explanatory view showing a magnet roller of a developing sleeve in a second embodiment.

【図１３】第２実施例における磁石ローラと磁石シール
部材を示す説明図である。FIG. 13 is an explanatory view showing a magnet roller and a magnet seal member in a second embodiment.

【図１４】第２比較例における磁石ローラと磁石シール
部材を示す説明図である。FIG. 14 is an explanatory view showing a magnet roller and a magnet seal member in a second comparative example.

【図１５】第３実施例における現像スリーブの磁石ロー
ラを示す説明図である。FIG. 15 is an explanatory diagram illustrating a magnet roller of a developing sleeve according to a third embodiment.

【図１６】第３実施例における磁石ローラと磁石シール
部材を示す説明図である。FIG. 16 is an explanatory view showing a magnet roller and a magnet seal member in a third embodiment.

【図１７】第３実施例における磁石シール部材の磁極か
らの磁力線を示す説明図である。FIG. 17 is an explanatory diagram showing lines of magnetic force from the magnetic poles of the magnet seal member in the third embodiment.

【図１８】従来の現像装置の一例を示す断面図である。FIG. 18 is a cross-sectional view illustrating an example of a conventional developing device.

【図１９】図１８の現像装置の端部シール構造を示す断
面図である。19 is a cross-sectional view illustrating an end seal structure of the developing device of FIG. 18;

【図２０】磁石シール部材を備えた従来の現像装置の一
例を示す断面図である。FIG. 20 is a cross-sectional view illustrating an example of a conventional developing device including a magnet seal member.

【図２１】図２０の磁石シール部材の着磁パターンを示
す斜視図である。FIG. 21 is a perspective view showing a magnetization pattern of the magnet seal member of FIG. 20;

【図２２】従来の規制ブレード（磁性ブレード）と現像
スリーブ内の磁石の磁極との位置関係を示す説明図であ
る。FIG. 22 is an explanatory diagram showing a positional relationship between a conventional regulating blade (magnetic blade) and a magnetic pole of a magnet in a developing sleeve.

【図２３】従来の規制ブレード（弾性ブレード）と現像
スリーブ内の磁石の磁極との位置関係を示す説明図であ
る。FIG. 23 is an explanatory diagram showing a positional relationship between a conventional regulating blade (elastic blade) and a magnetic pole of a magnet in a developing sleeve.

【符号の説明】[Explanation of symbols]

１ 感光ドラム（像担持体・電子写真感光体） ３ 現像装置 ３１ 現像スリーブ（現像剤担持体） ３２ 磁石ローラ（磁界発生手段） ３３ 規制ブレード（現像剤規制手段） ３４ 磁石シール部材 REFERENCE SIGNS LIST 1 photosensitive drum (image carrier / electrophotographic photosensitive member) 3 developing device 31 developing sleeve (developer carrier) 32 magnet roller (magnetic field generating means) 33 regulating blade (developer regulating means) 34 magnet seal member

Claims (12)

【特許請求の範囲】[Claims] 【請求項１】 磁性現像剤を収容する現像容器と、該現
像容器に回転自在に支持され、複数の磁極を備えた磁界
発生手段を内部に固定配置することにより磁性現像剤を
担持搬送する現像剤担持体とを有する現像装置におい
て、 前記現像剤担持体の両端部にその外周面と所定間隙をも
って配置された複数の磁極を備えた磁石シール部材を有
し、前記磁石シール部材は、前記磁石シール部材の前記
現像剤担持体移動方向端部の端部磁極と、前記端部磁極
と対応する前記磁界発生手段の少なくとも一つの前記磁
極とがずれるように配置され、前記端部磁極と対応する
前記磁界発生手段の前記磁極とは同極性として、前記磁
界発生手段の前記端部磁極と対向する部位に逆極性の磁
極を誘起させて仮想的にＮＳの順磁界を形成させること
を特徴とする現像装置。1. A developing device for carrying and transporting a magnetic developer by fixedly arranging therein a developing container containing a magnetic developer and a magnetic field generating means rotatably supported by the developing container and having a plurality of magnetic poles. A developer carrier having a magnet seal member having a plurality of magnetic poles disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface thereof, wherein the magnet seal member is provided with the magnet An end magnetic pole at the end of the developer carrier moving direction of the seal member and at least one of the magnetic poles of the magnetic field generating means corresponding to the end magnetic pole are arranged so as to be shifted from each other, and correspond to the end magnetic pole. The magnetic pole of the magnetic field generating means has the same polarity as that of the magnetic field generating means, and a magnetic pole of opposite polarity is induced at a portion facing the end magnetic pole to virtually form a forward magnetic field of NS. Present Apparatus. 【請求項２】 磁性現像剤を収容する現像容器と、該現
像容器に回転自在に支持され、内部に磁界発生手段を固
定配置することにより磁性現像剤を担持搬送する現像剤
担持体とを有する現像装置において、 前記現像剤担持体の両端部に、前記現像剤担持体の外周
面と所定間隙をもって磁石シール部材を配置し、前記磁
石シール部材の前記現像剤担持体と対向する領域の現像
剤搬送方向出口側の部位に出口側磁極を配置し、前記出
口側磁極よりも前記現像剤担持体移動方向下流側に前記
磁界発生手段の磁極を配置し、前記磁界発生手段の磁極
と前記磁石シール部材の前記出口側磁極とを同極性とし
て、前記磁界発生手段の前記出口側磁極と対向する部位
に逆極性の磁極を誘起させて仮想的にＮＳの順磁界を形
成させることを特徴とする現像装置。2. A developer container containing a magnetic developer, and a developer carrier rotatably supported by the developer container and carrying the magnetic developer by fixing and arranging a magnetic field generating means inside the developer container. In the developing device, a magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from an outer peripheral surface of the developer carrier, and a developer is provided in a region of the magnet seal member facing the developer carrier. An outlet-side magnetic pole is disposed at a position on the outlet side in the transport direction, and a magnetic pole of the magnetic field generating unit is disposed downstream of the outlet-side magnetic pole in the direction of movement of the developer carrier, and a magnetic pole of the magnetic field generating unit and the magnet seal are disposed. Developing the magnetic field generating means with the same polarity as the outlet side magnetic pole and inducing a magnetic pole of opposite polarity at a portion of the magnetic field generating means facing the outlet side magnetic pole to virtually form a forward magnetic field of NS. apparatus 【請求項３】 磁性現像剤を収容する現像容器と、該現
像容器に回転自在に支持され、内部に磁界発生手段を固
定配置することにより磁性現像剤を担持搬送する現像剤
担持体とを有する現像装置において、 前記現像剤担持体の両端部に、前記現像剤担持体の外周
面と所定間隙をもって磁石シール部材を配置し、前記磁
石シール部材の前記現像剤担持体と対向する領域の現像
剤搬送方向入口側の部位に入口側磁極を配置し、前記出
口側磁極よりも前記現像剤担持体移動方向上流側に前記
磁界発生手段の磁極を配置し、前記磁界発生手段の磁極
と前記磁石シール部材の入口側磁極を同極性として、前
記磁界発生手段の前記入口側磁極と対向する部位に逆極
性の磁極を誘起させて仮想的にＮＳの順磁界を形成させ
ることを特徴とする現像装置。3. A developing container containing a magnetic developer, and a developer carrier rotatably supported by the developing container and carrying the magnetic developer by fixing and arranging a magnetic field generating means therein. In the developing device, a magnet seal member is disposed at both ends of the developer carrier with a predetermined gap from an outer peripheral surface of the developer carrier, and a developer is provided in a region of the magnet seal member facing the developer carrier. An inlet-side magnetic pole is disposed at a portion on the inlet side in the transport direction, and a magnetic pole of the magnetic field generating unit is disposed upstream of the outlet-side magnetic pole in the direction of movement of the developer carrier, and a magnetic pole of the magnetic field generating unit and the magnet seal are disposed. A developing device, wherein the inlet-side magnetic pole of the member has the same polarity, and a magnetic pole of an opposite polarity is induced at a portion of the magnetic field generating means facing the inlet-side magnetic pole to virtually form a forward magnetic field of NS. 【請求項４】 前記磁界発生手段は表面が着磁された複
数の磁石ブロックと前記複数の磁石ブロックの間を占め
る磁性部材とを含むことを特徴とする請求項１、２、ま
たは３の現像装置。4. The developing device according to claim 1, wherein said magnetic field generating means includes a plurality of magnet blocks whose surfaces are magnetized and a magnetic member occupying a space between said plurality of magnet blocks. apparatus. 【請求項５】 画像形成装置本体に着脱可能なプロセス
カートリッジにおいて、 少なくとも電子写真感光体と、現像装置とを有し、前記
現像装置は、磁性現像剤を収容する現像容器と、該現像
容器に回転自在に支持され、複数の磁極を備えた磁界発
生手段を内部に固定配置することにより磁性現像剤を担
持搬送する現像剤担持体と、前記現像剤担持体の両端部
にその外周面と所定間隙をもって配置された複数の磁極
を備えた磁石シール部材と、を有し、前記磁石シール部
材は、前記磁石シール部材の前記現像剤担持体移動方向
端部の端部磁極と、前記端部磁極と対応する前記磁界発
生手段の少なくとも一つの前記磁極とがずれるように配
置され、前記端部磁極と対応する前記磁界発生手段の前
記磁極とを同極性として、前記磁界発生手段の前記端部
磁極と対向する部位に逆極性の磁極を誘起させて仮想的
にＮＳの順磁界を形成させることを特徴とするプロセス
カートリッジ。5. A process cartridge detachably mountable to an image forming apparatus main body, comprising: at least an electrophotographic photosensitive member; and a developing device, wherein the developing device includes a developing container containing a magnetic developer, and a developing container. A developer carrying member rotatably supported and carrying a magnetic developer by fixedly arranging a magnetic field generating means having a plurality of magnetic poles therein, and an outer peripheral surface thereof at both ends of the developer carrying member and a predetermined distance from each other. A magnet seal member provided with a plurality of magnetic poles arranged with a gap, wherein the magnet seal member has an end magnetic pole at an end of the magnet seal member in the developer carrier moving direction, and the end magnetic pole. And at least one of the magnetic poles of the magnetic field generating means corresponding to the magnetic field generating means is disposed so as to be deviated, and the end magnetic pole and the corresponding magnetic pole of the magnetic field generating means have the same polarity, and A process cartridge, characterized in that to form a forward field of end magnetic pole facing virtually by inducing a reverse polarity magnetic poles of the site of NS. 【請求項６】 画像形成装置本体に着脱可能なプロセス
カートリッジにおいて、 少なくとも電子写真感光体と、現像装置とを有し、前記
現像装置は、磁性現像剤を収容する現像容器と、該現像
容器に回転自在に支持され、内部に磁界発生手段を固定
配置することにより磁性現像剤を担持搬送する現像剤担
持体とを有し、前記現像剤担持体の両端部に、前記現像
剤担持体の外周面と所定間隙をもって磁石シール部材を
配置し、前記磁石シール部材の前記現像剤担持体と対向
する領域の現像剤搬送方向出口側の部位に出口側磁極を
配置し、前記出口側磁極よりも前記現像剤担持体移動方
向下流側に前記磁界発生手段の磁極を配置し、前記磁界
発生手段の磁極と前記磁石シール部材の前記出口側磁極
とを同極性として、前記磁界発生手段の前記出口側磁極
と対向する部位に逆極性の磁極を誘起させて仮想的にＮ
Ｓの順磁界を形成させることを特徴とするプロセスカー
トリッジ。6. A process cartridge detachable from an image forming apparatus main body, comprising at least an electrophotographic photoreceptor and a developing device, wherein the developing device includes a developing container containing a magnetic developer, and a developing container. A developer carrying member rotatably supported and carrying the magnetic developer by fixedly disposing a magnetic field generating means therein, and having an outer periphery of the developer carrying member at both ends of the developer carrying member. A magnet seal member is arranged with a predetermined gap from the surface, and an exit side magnetic pole is arranged at a portion of the magnet seal member on the exit side in the developer transport direction in a region facing the developer carrier, and the exit side magnetic pole is more than the exit side magnetic pole. The magnetic pole of the magnetic field generating means is arranged downstream of the developer carrier moving direction, and the magnetic pole of the magnetic field generating means and the outlet magnetic pole of the magnet seal member have the same polarity. Virtually N by inducing a reverse polarity magnetic poles of the site poles facing
A process cartridge for forming a forward magnetic field of S. 【請求項７】 画像形成装置本体に着脱可能なプロセス
カートリッジにおいて、 少なくとも電子写真感光体と、現像装置とを有し、前記
現像装置は、磁性現像剤を収容する現像容器と、該現像
容器に回転自在に支持され、内部に磁界発生手段を固定
配置することにより磁性現像剤を担持搬送する現像剤担
持体とを有し、前記現像剤担持体の両端部に、前記現像
剤担持体の外周面と所定間隙をもって磁石シール部材を
配置し、前記磁石シール部材の前記現像剤担持体と対向
する領域の現像剤搬送方向入口側の部位に入口側磁極を
配置し、前記出口側磁極よりも前記現像剤担持体移動方
向上流側に前記磁界発生手段の磁極を配置し、前記磁界
発生手段の磁極と前記磁石シール部材の入口側磁極を同
極性として、前記磁界発生手段の前記入口側磁極と対向
する部位に逆極性の磁極を誘起させて仮想的にＮＳの順
磁界を形成させることを特徴とするプロセスカートリッ
ジ。7. A process cartridge detachably mountable to an image forming apparatus main body, comprising at least an electrophotographic photoreceptor and a developing device, wherein the developing device includes a developing container containing a magnetic developer, and a developing container. A developer carrying member rotatably supported and carrying the magnetic developer by fixedly disposing a magnetic field generating means therein, and having an outer periphery of the developer carrying member at both ends of the developer carrying member. A magnet seal member is arranged with a predetermined gap from the surface, and an entrance-side magnetic pole is arranged at a portion of the magnet seal member on the entrance side in the developer conveyance direction in a region facing the developer carrier, and the magnetic pole is more than the exit-side magnetic pole. The magnetic pole of the magnetic field generating means is arranged on the upstream side in the developer carrier moving direction, and the magnetic pole of the magnetic field generating means and the inlet magnetic pole of the magnet seal member have the same polarity, and the inlet magnetic pole of the magnetic field generating means is provided. The process cartridge for causing induced causes the reverse polarity magnetic poles of the portion facing to virtually form a forward field of NS. 【請求項８】 前記磁界発生手段は表面が着磁された複
数の磁石ブロックと前記複数の磁石ブロックの間を占め
る磁性部材とを含むことを特徴とする請求項５、６、ま
たは７のプロセスカートリッジ。8. The process according to claim 5, wherein the magnetic field generating means includes a plurality of magnet blocks whose surfaces are magnetized and a magnetic member occupying a space between the plurality of magnet blocks. cartridge. 【請求項９】 少なくとも電子写真感光体と現像装置を
含むプロセスカートリッジを着脱可能な画像形成装置に
おいて、 前記現像装置は、磁性現像剤を収容する現像容器と、該
現像容器に回転自在に支持され、複数の磁極を備えた磁
界発生手段を内部に固定配置することにより磁性現像剤
を担持搬送する現像剤担持体と、前記現像剤担持体の両
端部にその外周面と所定間隙をもって配置された複数の
磁極を備えた磁石シール部材と、を有し、前記磁石シー
ル部材は、前記磁石シール部材の前記現像剤担持体移動
方向端部の端部磁極と、前記端部磁極と対応する前記磁
界発生手段の少なくとも一つの前記磁極とがずれるよう
に配置され、前記端部磁極と対応する前記磁界発生手段
の前記磁極とを同極性として、前記磁界発生手段の前記
端部磁極と対向する部位に逆極性の磁極を誘起させて仮
想的にＮＳの順磁界を形成させることを特徴とする画像
形成装置。9. An image forming apparatus in which a process cartridge including at least an electrophotographic photosensitive member and a developing device is detachable, wherein the developing device is rotatably supported by the developing container containing a magnetic developer. A magnetic field generating means having a plurality of magnetic poles is fixedly disposed inside, and a developer carrier for carrying and transporting a magnetic developer is disposed at both ends of the developer carrier with a predetermined gap from the outer peripheral surface thereof. A magnet seal member having a plurality of magnetic poles, wherein the magnet seal member has an end magnetic pole at an end of the developer carrier moving direction of the magnet seal member, and the magnetic field corresponding to the end magnetic pole. The end magnetic poles of the magnetic field generating means are arranged so that at least one of the magnetic poles of the generating means is displaced, and the end magnetic poles and the corresponding magnetic poles of the magnetic field generating means have the same polarity. An image forming apparatus characterized in that the reverse polarity magnetic poles of the portion facing to induce the formation of forward field of virtually NS with. 【請求項１０】 少なくとも電子写真感光体と現像装置
とを含むプロセスカートリッジを着脱可能な画像形成装
置において、 前記現像装置は、磁性現像剤を収容する現像容器と、該
現像容器に回転自在に支持され、内部に磁界発生手段を
固定配置することにより磁性現像剤を担持搬送する現像
剤担持体とを有し、前記現像剤担持体の両端部に、前記
現像剤担持体の外周面と所定間隙をもって磁石シール部
材を配置し、前記磁石シール部材の前記現像剤担持体と
対向する領域の現像剤搬送方向出口側の部位に出口側磁
極を配置し、前記出口側磁極よりも前記現像剤担持体移
動方向下流側に前記磁界発生手段の磁極を配置し、前記
磁界発生手段の磁極と前記磁石シール部材の前記出口側
磁極とを同極性として、前記磁界発生手段の前記出口側
磁極と対向する部位に逆極性の磁極を誘起させて仮想的
にＮＳの順磁界を形成させることを特徴とする画像形成
装置。10. An image forming apparatus in which a process cartridge including at least an electrophotographic photosensitive member and a developing device is detachable, wherein the developing device is rotatably supported by the developing container containing a magnetic developer. And a developer carrier that carries and transports the magnetic developer by fixedly disposing a magnetic field generating means therein, and a predetermined gap between the outer peripheral surface of the developer carrier and both ends of the developer carrier. An outlet side magnetic pole is arranged at a portion of the magnet seal member on the outlet side in the developer conveying direction in a region facing the developer carrier, and the developer carrier is disposed more than the outlet side magnetic pole. The magnetic pole of the magnetic field generating means is arranged on the downstream side in the moving direction, and the magnetic pole of the magnetic field generating means and the outlet magnetic pole of the magnet seal member have the same polarity, and the outlet magnetic pole of the magnetic field generating means An image forming apparatus characterized in that the reverse polarity magnetic poles of the portion facing to induce the formation of forward field of virtually NS with. 【請求項１１】 少なくとも電子写真感光体と現像装置
とを含むプロセスカートリッジを着脱可能な画像形成装
置において、 前記現像装置は、磁性現像剤を収容する現像容器と、該
現像容器に回転自在に支持され、内部に磁界発生手段を
固定配置することにより磁性現像剤を担持搬送する現像
剤担持体とを有し、前記現像剤担持体の両端部に、前記
現像剤担持体の外周面と所定間隙をもって磁石シール部
材を配置し、前記磁石シール部材の前記現像剤担持体と
対向する領域の現像剤搬送方向入口側の部位に入口側磁
極を配置し、前記出口側磁極よりも前記現像剤担持体移
動方向上流側に前記磁界発生手段の磁極を配置し、前記
磁界発生手段の磁極と前記磁石シール部材の入口側磁極
を同極性として、前記磁界発生手段の前記入口側磁極と
対向する部位に逆極性の磁極を誘起させて仮想的にＮＳ
の順磁界を形成させることを特徴とする画像形成装置。11. An image forming apparatus in which a process cartridge including at least an electrophotographic photoreceptor and a developing device is detachable, wherein the developing device is rotatably supported by the developing container containing a magnetic developer. And a developer carrier that carries and transports the magnetic developer by fixedly disposing a magnetic field generating means therein, and a predetermined gap between the outer peripheral surface of the developer carrier and both ends of the developer carrier. An inlet-side magnetic pole is disposed at a portion of the magnet seal member on the inlet side in the developer conveying direction in a region facing the developer carrier, and the developer-carrying member is disposed above the outlet-side magnetic pole. The magnetic pole of the magnetic field generating means is arranged on the upstream side in the moving direction, and the magnetic pole of the magnetic field generating means and the inlet magnetic pole of the magnet seal member have the same polarity, and are opposed to the inlet magnetic pole of the magnetic field generating means. Virtually NS by inducing a reverse polarity magnetic poles of the site that
An image forming apparatus for forming a forward magnetic field. 【請求項１２】 前記磁界発生手段は表面が着磁された
複数の磁石ブロックと前記複数の磁石ブロックの間を占
める磁性部材とを含むことを特徴とする請求項９、１
０、または１１の画像形成装置。12. The magnetic field generating means according to claim 9, wherein said magnetic field generating means includes a plurality of magnet blocks whose surfaces are magnetized and a magnetic member occupying a space between said plurality of magnet blocks.
0 or 11 image forming apparatus.
JP14000499A 1999-05-20 1999-05-20 Developing device, processing cartridge, and image forming device Pending JP2000330384A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14000499A JP2000330384A (en) 1999-05-20 1999-05-20 Developing device, processing cartridge, and image forming device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14000499A JP2000330384A (en) 1999-05-20 1999-05-20 Developing device, processing cartridge, and image forming device

Publications (1)

Publication Number Publication Date
JP2000330384A true JP2000330384A (en) 2000-11-30

Family

ID=15258702

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14000499A Pending JP2000330384A (en) 1999-05-20 1999-05-20 Developing device, processing cartridge, and image forming device

Country Status (1)

Country Link
JP (1) JP2000330384A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009031590A (en) * 2007-07-27 2009-02-12 Kyocera Mita Corp Developing device and image forming apparatus equipped with the same
AU2007201510B2 (en) * 2006-06-01 2010-08-19 Fujifilm Business Innovation Corp. Development device and image forming apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2007201510B2 (en) * 2006-06-01 2010-08-19 Fujifilm Business Innovation Corp. Development device and image forming apparatus
JP2009031590A (en) * 2007-07-27 2009-02-12 Kyocera Mita Corp Developing device and image forming apparatus equipped with the same

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