JPH03206481A - Developing device - Google Patents

Abstract

PURPOSE:To prevent a developer from sticking on the end surfaces of a developing roller in a developing device main body in lumps even if the developer enters the gaps between the axial end surfaces of the developing roller and the developing device main body by fitting a cleaning member which is rubbed against the axial end parts of the developing roller in the developing main body wherein the developing roller is stored and held. CONSTITUTION:The developing device 3 which has the developing roller 20 stored in the developing device main body 10 has gaps formed between the end surfaces of the developing roller and the internal surface of the developing device main body, so the developer when entering the gaps is pressed to stick on the end surfaces of the developing roller 20. The cleaning member 30 which is rubbed against the end surfaces of the developing roller 20 is fitted on the side of the developing device main body 10 to clean the end surfaces of the developing roller 20 at all times. Consequently, the developer which is pressed by the developing device main body 109 and the end surfaces of the developing roller 20, etc., never sticks on the end surface of the developing roller 20.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は電子写真方式を採用する複写機等の画像形成装
置の現像装置に関する． （従来の技術） 複写機等においては、像担持体に形成された潜像に現像
剤（トナー）を供給し，この潜像をトナー像として顕像
化する必要があるが，かかる現像作業は現像装置によっ
てなされる．現像装置の現像器本体内には像担持体に対
向して一定方向に回転する現像ローラが配設され、現像
器本体内のトナーをこの現像ローラ周りに磁気保持して
像担持体の方へ供給している．そして現像ローラはその
軸方向両端から外方に突出する支軸を介して現像器本体
の両側壁に回転自在に支持されている． （発明が解決しようとする課ＩＩ） しかしながら従来の現像装置においては、現像器本体内
のトナーが現像器本体の側壁内面と現像ローラの端面間
に入り込み、このトナーが加圧されて、長時間の使用中
にこのトナーが現像ローラの端面に付着し現像ローラの
回転を困難にしたり、または付着トナーがトナー塊とな
って落下し、現像に供されて画像を乱してしまうという
不都合があった． また上記トナー塊が現像ローラと一定の隙間を有する如
く配設される現像ブレードを通過できず，現像ローラ上
に不均一なトナー層を形成し、像担持体上の画像にいわ
ゆる白スジを発生させてしまうという不都合があった． 本発明は上記問題に鑑みてなされたもので，その目的と
する処は，現像ローラの軸方向端面と現像器本体間に現
像剤が侵入しても，現像ローラ端面に現像剤を塊状に付
着させることのない現像装置を提供するにある． （課題を解決するための手段） 上記目的を達成すべく本発明は、一定方向に回転する現
像ローラ周りに現像剤を磁気保持して，該現像剤を像担
持体の方へ供給する現像装置において，現像ローラな収
納支持する現像器本体内に、該現像器本体内の現像ロー
ラの軸方向端部に摺擦するクリーニング部材を取付けた
ことを特徴とする． （作用） 現像ローラが現像器本体内に収納されている現像装置で
は現像ローラの端面と現像器本体内面間に隙間が形成さ
れるため，この隙間に現像剤が入り込めば，現像剤が加
圧され，該現像剤が現像ローラの端面に付着する． そこで，現像器本体側に現像ローラの端面に摺擦するク
リーニング部材を取付け、常時現像ローラの端面をクリ
ーニングするようにしたため，現像ローラ端面に現像剤
が塊状に付着することはない． （実施例） 以下に本発明の実施例を添付図面に基づいて説明する． まず第１図により画像形成装置による画像形成作業の概
要を説明すれば，図中１は一定方向に回転する像担持体
としての感光ドラムであり、該感光ドラムｌの周りには
一次帯電器２，現像装置３，転写帯電器４，クリーニン
グ器５が配設されている． 即ち、一次帯電器２により一様帯電された感光トラムｌ
上に不図示のスキャナユニット等から画像光Ｌが露光さ
れると、感光トラムｌ上には静電潜像が形威される．該
静電潜像は感光ドラムｌの回転とともに現像装置３の方
へ向けられ，該現像装１ｌ３により現像剤（トナー）Ｔ
が供給されてトナー像として顕像化される．そしてこの
トナー像は転写帯電器４により転写紙Ｐ上に転写され，
転写の終了した感光ドラムｌはクリーニング器５により
その残留トナーがクリーニングされる．尚、トナー像が
転写された転写紙Ｐは不図示の定着器の方へ運ばれ，該
定着器によりそのトナー像が永久像として定着される． つぎに現像装ｌＩ３について更に説明すれば、該現像装
１１３は内部にトナーＴを保有する現像器本体１０と，
該現像器本体ｌＯ内で回転自在に支持され，内部に看す
る磁石等を介して現像器本体ＩＯ内のトナーＴを磁気保
持して該トナーＴを感光ドラムｌの方へ供給する現像ロ
ーラ２０と，現像器本体１０に現像ローラ２０と僅かな
隙間を有する如く取付けられ，現像ローラ２０周りに磁
気保持されたトナーＴを一定厚さにして感光ドラムｌの
方へ供給させる現像ブレード２１等とから構成されてい
る．尚、現像ローラ２０は現像器本体１０から感光ドラ
ムｌ偏に一部突出する如く、現像器本体ｌＯ内に支持さ
れ、不図示の回転手段によって回転される． また，現像装置３内のトナーＴは磁性トナー又は非磁性
トナーのいずれでもよく，非磁性トナーの場合，該トナ
ーＴは現像ローラ２０の回転や現像器本体ｌＯ内の不図
示の攪拌部材等を介して摩擦帯電され現像ローラ２０に
磁気保持されることとなる． さて、現像ローラ２０の現像器本体ｌＯによる支持状態
を第２図及び第３図で説明すれば，現像ローラ２０の軸
方向端面にはローラ支軸２０ａが突出し、該ローラ支輌
２０ａが現像器本体ｌＯの側壁１１に取付けられたベア
リングｌ２に支持されている．従って現像ローラ２０の
端面２０ｂと現像器本体１０の側壁１１の内面間には僅
かな隙間ｌ３が形成されているが、現像器ｌＯのトナー
Ｔがこの隙間ｌ３内に入り込み、現像ローラ２０の端面
２０ｂやローラ支軸２０ａと、ベアリング１２や現像器
本体１０の側壁１ｌとの間でトナーＴが加圧され，該加
圧トナーＴが現像ローラ２０の端面２０ｂ　　長期間の
内に順次付着して現像ローラ２０の回転を困難にすると
いう不都合がある． また上記付着トナーＴがトナー塊となって落下し、該ト
ナー塊が現像ローラ２０の外周面に付着して感光ドラム
ｌ上の画像を乱したり，更にこのトナー塊か現像ブレー
ド２ｌと現像ローラ２０間の隙間より大きければ、現像
ローラ２０外周面上のこのトナー塊は現像ブレード２１
を通過できず、現像ローラ２０の回転に伴い該現像ロー
ラ２０上に不均一なトナー層を形成させ、感光ドラムｌ
上の画像に白スジを発生させてしまうという不都合があ
る． そこで本発明では、現像ローラ２０の端面２０ｂにクリ
ーニング部材としてのスクレーパ３０を摺擦させ、現像
ローラ２０の端面２０ｂにトナーＴが塊となって付着し
ないようにした．即ち，現像器本体ｌＯの側壁ｌ１の外
端面に第３図で示される如く，現像ローラ２０が現像器
本体ｌＯから突出する部分の弦の長さよりやや長いスク
レーバ３０を上下方向に取付け、該スクレーバ３０の内
端部を現像ローラ２０の端面２０ｂに摺擦させるように
した．このスクレーパ３０の材質はステンレスの如き非
磁性の金属やゴム類の如く弾力性を有する非磁性の材料
であることが好ましい．磁性部材の場合は，トナーＴが
付着し易いため、定期的な清掃を必要とする． 而して、現像トナー２０の端面２０ｂと現像器本体ｌＯ
の側壁１１とで形成される隙間ｌ３にトナーＴが入り込
み、現像ローラ２０の端面２０ｂにトナーＴが加圧され
て付着しようとしても、該加圧トナーＴは現像ローラ２
０の回転とともにスクレーバ３０で直ちに除去され、現
像ローラ２０の端面２０ｂにトナーＴが塊となって付着
することはない．従って、現像ローラ２０の端面２０ｂ
にトナーＴが付着することによって生じる種々のトラブ
ルを防止できる． ここで現像ローラ２０の端面２０ｂと現像器本体ｌＯの
側壁１１内面とで形成される隙間ｌ３の下方に、現像器
本体１０内の現像ローラ２０の径方向長さに略等しい磁
石３ｌを配設すれば、もし現像ローラ２０の端面２０ｂ
にトナーＴが付着し該トナーＴがトナー塊となってスク
レーバ３０により除去された場合でも、このトナー塊を
磁石３ｌで直ちに補集でき、このトナー塊が現像作業に
供されるという不都合を回避することができる． また第４図で示される如く、クリーニング部材として現
像器本体ｌＯの側壁ｌｌ内面に現像ローラ２０の端面２
０ｂに摺擦するブラシ３２を取付でも上記と同様な効果
を得ることができる．この場合もブラシ３２の下方の現
像器本体ｌＯ内に磁石３ｌを配設してもよい． 更に第５図で示される如く、現像ローラ２０の端面ｚｏ
ｂと現ａｍ本体ｌＯの側壁１１間の隙間ｌ３に髭上のブ
ラシ３３を挿入し、この隙間ｌ３内へのトナーＴの侵入
を防止しても同様な効果が得られる． （発明の効果） 以上の説明で明らかな如く本発明によれば，現像器本体
内の現像ローラ端面を常時クリーニング部材で摺擦して
いるため、現像器本体と現像ローラ端面等とで加圧され
た現像剤が現像ローラの端面に付着することはない． 従って現像ローラ端面に現像剤の塊が付着することによ
って生じる種々のトラブルを解消できる．DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a developing device for an image forming apparatus such as a copying machine that employs an electrophotographic method. (Prior Art) In copying machines and the like, it is necessary to supply a developer (toner) to a latent image formed on an image carrier and visualize this latent image as a toner image. This is done by a developing device. A developing roller that rotates in a fixed direction facing the image carrier is disposed inside the developing device body of the developing device, and the toner in the developing device body is magnetically held around this developing roller and directed toward the image carrier. We are supplying. The developing roller is rotatably supported on both side walls of the developing device body via support shafts that protrude outward from both axial ends of the developing roller. (Problem II to be Solved by the Invention) However, in the conventional developing device, the toner inside the developing device main body enters between the inner surface of the side wall of the developing device main body and the end surface of the developing roller, and this toner is pressurized for a long time. During use, this toner may adhere to the end surface of the developing roller, making it difficult to rotate the developing roller, or the adhering toner may fall as toner clumps and be used for development, disturbing the image. Ta. Furthermore, the toner mass cannot pass through the developing blade which is arranged with a certain gap between it and the developing roller, forming an uneven toner layer on the developing roller and causing so-called white streaks on the image on the image carrier. There was the inconvenience of letting it happen. The present invention has been made in view of the above problem, and its purpose is to prevent the developer from sticking to the end surface of the developing roller in a lump even if the developer enters between the axial end surface of the developing roller and the main body of the developing device. The purpose is to provide a developing device that does not cause any damage. (Means for Solving the Problems) In order to achieve the above object, the present invention provides a developing device that magnetically holds a developer around a developing roller that rotates in a fixed direction and supplies the developer toward an image carrier. A cleaning member that rubs against the axial end of the developing roller in the developing device main body is installed in the developing device main body that accommodates and supports the developing roller. (Function) In a developing device in which the developing roller is housed in the developing device main body, a gap is formed between the end surface of the developing roller and the inner surface of the developing device main body, so if the developer enters this gap, the developer will be heated. The developer adheres to the end surface of the developing roller. Therefore, a cleaning member that rubs against the end surface of the developing roller is attached to the developing device body side, and the end surface of the developing roller is constantly cleaned, so that the developer does not stick to the end surface of the developing roller in the form of a lump. (Example) Examples of the present invention will be described below based on the attached drawings. First, an outline of the image forming operation by an image forming apparatus will be explained with reference to FIG. , a developing device 3, a transfer charger 4, and a cleaning device 5 are provided. That is, the photosensitive tram l uniformly charged by the primary charger 2
When image light L is exposed from a scanner unit (not shown) or the like above, an electrostatic latent image is formed on the photosensitive tram l. The electrostatic latent image is directed toward the developing device 3 as the photosensitive drum 1 rotates, and the developing device 113 turns the electrostatic latent image into a developer (toner) T.
is supplied and visualized as a toner image. This toner image is then transferred onto the transfer paper P by the transfer charger 4,
The photosensitive drum 1 after the transfer is cleaned of residual toner by a cleaning device 5. The transfer paper P onto which the toner image has been transferred is conveyed to a fixing device (not shown), and the toner image is fixed as a permanent image by the fixing device. Next, to further explain the developing device 113, the developing device 113 includes a developing device main body 10 containing toner T therein,
A developing roller 20 is rotatably supported within the developing device main body IO, magnetically holds the toner T in the developing device main body IO via a magnet or the like located inside, and supplies the toner T toward the photosensitive drum 1. and a developing blade 21, etc., which is attached to the developing device main body 10 with a slight gap from the developing roller 20 and supplies the toner T, which is magnetically held around the developing roller 20, to a constant thickness toward the photosensitive drum l. It is composed of. The developing roller 20 is supported within the developing device main body 10 so as to partially protrude from the developing device main body 10 toward the photosensitive drum 1, and is rotated by a rotating means (not shown). Further, the toner T in the developing device 3 may be either magnetic toner or non-magnetic toner, and in the case of non-magnetic toner, the toner T is rotated by the rotation of the developing roller 20 or by a stirring member (not shown) in the developing device main body 1O. The developing roller 20 is then frictionally charged and held magnetically by the developing roller 20. Now, to explain the state in which the developing roller 20 is supported by the developing device main body lO with reference to FIGS. It is supported by a bearing l2 attached to the side wall 11 of the main body lO. Therefore, a slight gap l3 is formed between the end surface 20b of the developing roller 20 and the inner surface of the side wall 11 of the developing device main body 10, but the toner T of the developing device IO enters into this gap l3, and the end surface of the developing roller 20 The toner T is pressurized between the roller support shaft 20b and the roller support shaft 20a, and the bearing 12 and the side wall 1l of the developing device main body 10, and the pressurized toner T gradually adheres to the end surface 20b of the developing roller 20 over a long period of time. This has the disadvantage of making it difficult to rotate the developing roller 20. Further, the adhered toner T falls as toner lumps, and the toner lumps adhere to the outer peripheral surface of the developing roller 20 and disturb the image on the photosensitive drum l. 20, this toner mass on the outer peripheral surface of the developing roller 20 will be removed by the developing blade 21.
As the developing roller 20 rotates, an uneven toner layer is formed on the developing roller 20, causing the toner to pass through the photosensitive drum l.
This has the inconvenience of causing white streaks in the image above. Therefore, in the present invention, a scraper 30 as a cleaning member is rubbed against the end surface 20b of the developing roller 20 to prevent the toner T from adhering to the end surface 20b of the developing roller 20 in the form of lumps. That is, as shown in FIG. 3, a scraper 30 that is slightly longer than the chord length of the portion where the developing roller 20 projects from the developing device main body 10 is vertically attached to the outer end surface of the side wall 11 of the developing device main body 10. The inner end of the roller 30 is made to rub against the end surface 20b of the developing roller 20. The material of the scraper 30 is preferably a non-magnetic metal such as stainless steel or a non-magnetic material having elasticity such as rubber. In the case of magnetic members, toner T tends to adhere to them, so regular cleaning is required. Thus, the end surface 20b of the developing toner 20 and the developing device main body lO
Even if the toner T enters the gap l3 formed between the side wall 11 of the developing roller 20 and the toner T is pressurized and tries to adhere to the end surface 20b of the developing roller 20, the pressurized toner T does not reach the developing roller 2.
The toner T is immediately removed by the scraper 30 as the toner T rotates, so that the toner T does not stick to the end surface 20b of the developing roller 20 in the form of a lump. Therefore, the end surface 20b of the developing roller 20
Various troubles caused by toner T adhering to the surface can be prevented. Here, below the gap l3 formed between the end surface 20b of the developing roller 20 and the inner surface of the side wall 11 of the developing device main body 10, a magnet 3l that is approximately equal to the radial length of the developing roller 20 in the developing device main body 10 is disposed. Then, if the end surface 20b of the developing roller 20
Even if the toner T adheres to the toner T and becomes a toner lump and is removed by the scraper 30, this toner lump can be immediately collected by the magnet 3l, thereby avoiding the inconvenience of the toner lump being used in the developing operation. can do. Further, as shown in FIG. 4, as a cleaning member, the end surface 2 of the developing roller 20 is attached to the inner surface of the side wall 11 of the developing device main body 10.
The same effect as described above can be obtained by installing a brush 32 for rubbing on 0b. In this case as well, a magnet 3l may be disposed within the developing device main body lO below the brush 32. Further, as shown in FIG. 5, the end surface zo of the developing roller 20
A similar effect can be obtained by inserting the whisker brush 33 into the gap l3 between the side wall 11 of the current AM main body lO and preventing the toner T from entering the gap l3. (Effects of the Invention) As is clear from the above description, according to the present invention, since the cleaning member constantly rubs the end surface of the developing roller in the developing device main body, pressure is applied between the developing device main body and the developing roller end surface, etc. The developed developer will not adhere to the end surface of the developing roller. Therefore, various troubles caused by developer lumps adhering to the end surface of the developing roller can be eliminated.

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

第１図は現像装置による画像形成作業を説明するための
図、第２図は現像装置の現像ローラ端部周りの正面図，
第３図は同現像ローラ端部周りの側面図、第４図及び第
５図は変更実施例に係る現像装置の現像ローラ端部周り
の正面図である．３・・・現像装置，１０・・・現像器
本体、２０・・・現像ローラ、３０・・・スクレーバ（
クリーニング部材），３２．３３−・・ブラシ（クリー
ニング部材）、Ｔ・・・トナー（現像剤）．Fig. 1 is a diagram for explaining the image forming operation by the developing device, Fig. 2 is a front view of the area around the developing roller end of the developing device,
FIG. 3 is a side view of the area around the end of the developing roller, and FIGS. 4 and 5 are front views of the area around the end of the developing roller of the developing device according to the modified embodiment. 3... Developing device, 10... Developing device main body, 20... Developing roller, 30... Scraper (
cleaning member), 32.33-...brush (cleaning member), T...toner (developer).

Claims (2)

【特許請求の範囲】[Claims] （１）一定方向に回転する現像ローラ周りに現像剤を磁
気保持して、該現像剤を像担持体の方へ供給する現像装
置において、現像ローラを収納支持する現像器本体内に
、該現像器本体内の現像ローラの軸方向端部に摺擦する
クリーニング部材を取付けたことを特徴とする現像装置
。(1) In a developing device that magnetically holds developer around a developing roller that rotates in a fixed direction and supplies the developer toward an image bearing member, the developing roller is housed and supported within the developing device body. A developing device characterized in that a cleaning member that rubs is attached to an axial end of a developing roller in a device main body. （２）前記クリーニング部材下方の現像器本体内に磁石
を配設したことを特徴とする請求項１記載の現像装置。(2) The developing device according to claim 1, further comprising a magnet disposed within the developing device body below the cleaning member.