JPS61262770A - Image forming device - Google Patents

Abstract

PURPOSE:To reduce the size and cost of an image forming device and to obtain the images having high quality by interposing a magnetic sealing member between two sleeves of adjacent developing devices and arranging plural developing devices. CONSTITUTION:A developing means 1 consists of three developing devices for cyan 2, magenta 3, and yellow 4, which are arranged successively along the surface of a photosensitive body 5. Each developing device has a hollow sleeve 7 made of a nonmagnetic material supported rotatably in a developing deice body 6 and a magnet roller 8 having plural magnetic poles arranged rotatably in the sleeve 7. A developer T accumulated at the right lower part of the developing device body 6 forms a magnetic brush held on the surface on the sleeve 7 with a magnetic field established by the magnet roller 8. Further, a magnetic sealing member 12 made of a magnetic material such as a copper silicate plate (of, for example, about 0.4mm in thickness) extending nearly in parallel to the magnet roller shaft is provided at a nearly center position between adjacent magnet roller poles so as to prevent magnetic fields produced by magnet rollers from operating on each other.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、現像器内に磁石ローラを有する複数個の現像
器を並設せしめた現像手段を備えた画像形成装置に関す
るものでらる。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image forming apparatus equipped with a developing means in which a plurality of developing devices each having a magnetic roller are arranged in parallel.

従来の技術 従来この種の画像形成装置は、例えばカラー複写装置が
おる。カラー複写装置の構成は、原稿を載置する原稿台
と、載置した原稿の画像を色分解露光する光学系と色分
解した原稿画像の静電潜像を形成する感光ドラム等の感
光体と、非磁性のスリーブ内に配置した磁石ローラを有
する現像器を感光体表面に沿って複数個並設した現像手
段と、転写ドラム等の転写手段と、転写材上に形成され
た未定着画像を定着する定着手段等より成り、色分解露
光、現象、転写等の所定プロセスを繰り返し転写材上に
複数色の未定着画像を形成し７後走着し、カラー複写画
像を得ている。2. Description of the Related Art Conventionally, this type of image forming apparatus includes, for example, a color copying apparatus. A color copying device consists of a document table on which a document is placed, an optical system that color-separates and exposes the image of the document placed thereon, and a photoconductor such as a photoconductor drum that forms an electrostatic latent image of the color-separated document image. , a developing means in which a plurality of developing devices each having a magnetic roller arranged in a non-magnetic sleeve are arranged side by side along the surface of the photoreceptor, a transfer means such as a transfer drum, and an unfixed image formed on the transfer material. It consists of a fixing means, etc., and repeats predetermined processes such as color separation exposure, phenomenon, and transfer to form unfixed images of a plurality of colors on a transfer material, and then runs the images after 7 to obtain a color copy image.

発明が解決しようとする問題点 このような従来の画像読取装置における現像手段では、
隣接する現像器のスリーブ内に配設した磁石ローラの磁
力の影響を避ける必要があり、感光ドラム等の感光体表
面に沿って複数個の現像器を並設する際に隣接する現像
器の各スリーブ間隔を十分に得るよう構成している。そ
のために、現像手段が大きくなるとともに現像手段と対
向する感光ドラム表面の周長を長く要し感光ドラムが大
きくなり、装置が大型で高価格になるという問題がおっ
た。隣接する現像器の磁石ローラの磁力を受けることに
より発生する問題点を以下に記載する。Problems to be Solved by the Invention In the developing means in such a conventional image reading device,
It is necessary to avoid the influence of the magnetic force of the magnetic rollers disposed in the sleeves of adjacent developing units. It is configured to provide sufficient sleeve spacing. As a result, the developing means becomes larger and the circumferential length of the surface of the photosensitive drum facing the developing means becomes longer, resulting in a larger photosensitive drum and a problem that the apparatus becomes larger and more expensive. Problems caused by the magnetic force of the magnetic rollers of adjacent developing units will be described below.

磁石ローラが固定でスリーブが回転する現像器を２個近
接して並設した現像手段においては、スリーブを回転さ
せることによりスリーブ上に現像剤を搬送させると対向
し合う各スリーブ面上にて現像剤の搬送能力が低下し現
像剤の供給不足や現像剤のたまり等が発生し、画像品質
の低下及び現像剤の落下に伴なう汚れ等の問題が生じる
。In a developing means in which two developing units in which a magnetic roller is fixed and a sleeve rotates are arranged in close proximity to each other, when the developer is conveyed onto the sleeve by rotating the sleeve, the developer is developed on the facing surfaces of each sleeve. The ability to transport the developer decreases, resulting in insufficient supply of developer, accumulation of developer, etc., resulting in problems such as deterioration of image quality and staining due to developer falling.

また、磁石ローラ及びスリーブが回転する現像器を２個
近接して並設した現像手段においては、磁石ローラ及び
スリーブを回転させることによりスリーブ上に現像剤を
搬送させる際に磁石ローラを回転させるだめの起動トル
りが増加するとともに、現像側の磁石ローラを回転させ
ることにより非現像側の磁石ローラの回転が起こりスリ
ーブ上への現像剤の搬送及び飛散等が発生し、高出力の
駆動源の採用に伴なう装置の高価格及び大型化、画像品
質の低下等の問題が生じる。In addition, in a developing means in which two developing units in which a magnetic roller and a sleeve rotate are arranged adjacently in parallel, the magnetic roller is rotated when the developer is conveyed onto the sleeve by rotating the magnetic roller and the sleeve. At the same time, the rotation of the magnetic roller on the developing side causes the magnetic roller on the non-developing side to rotate, causing the developer to be transported onto the sleeve and scattered, causing problems with the use of a high-output drive source. As a result of this adoption, problems arise such as the high cost and size of the device and the deterioration of image quality.

本発明は、隣接する現像器の磁石ローラの磁力による問
題点を解決し、複数個の現像器を近接し並設せしめた現
像手段を提供することにより、画像形成装置の小型化、
低価化及び高品質の画像を得るようにするものである。The present invention solves the problems caused by the magnetic force of magnetic rollers of adjacent developing devices, and provides a developing means in which a plurality of developing devices are arranged adjacently in parallel, thereby reducing the size of an image forming apparatus.
The purpose is to obtain low-cost and high-quality images.

問題点を解決するだめの手段 上記問題点を解決する本発明の技術的な手段は、隣接す
る現像器の２個のスリーブ間に磁気シール部材を介在せ
しめ複数個の現像器を並設するものでらる。Means for Solving the Problems The technical means of the present invention for solving the above problems is to arrange a plurality of developing devices in parallel by interposing a magnetic sealing member between two sleeves of adjacent developing devices. It comes out.

作用 本発明によれば、磁気シール部材により、隣接し合う現
像器内の磁石ローラの磁界による相互作用を防止でき、
この結果、複数個の現像器を近接し並設せしめても従来
と同程度の駆動源で磁石ローラを駆動できるとともに、
不要な混色も発生せず高品質の画像が得られる小型、低
価格の現像手段が得られるものである。According to the present invention, the magnetic seal member can prevent interaction due to the magnetic fields of magnetic rollers in adjacent developing devices.
As a result, even if multiple developing devices are installed in close proximity, the magnetic roller can be driven with the same drive source as before.
It is possible to obtain a small, low-cost developing means that can produce high-quality images without causing unnecessary color mixture.

実施例 以下、本発明の一実施例を添付図面にもとづいて説明す
る。Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

第１図において、現像手段１は、シアン２、マゼンタ３
、イエロ４用の３個の現像器で構成され、各々の現像器
は感光体６０表面に沿って並設されている。In FIG. 1, the developing means 1 includes cyan 2, magenta 3,
, Yellow 4, and each developing device is arranged in parallel along the surface of the photoreceptor 60.

各々の現像器は、現像器本体ｅ中に、回転可能に支持し
た非磁性材より成る中空のスリーブ７と、スリーブＴ内
に回転可能に配置され撹散の磁極を有する磁石ローラ８
が設けられている。現像器本体６右下部に蓄積された現
像剤では、磁石ローラ８により形成される磁界により、
スリーブ７表面に保持され現像ブラシを形成する。この
現像ブラシの穂立ち高さを調整する為、ドクターブレー
ド９は、その先端をスリーブ７表面に対し所定間隔を保
つように現像器本体６に固定的に設置される。Each developing device includes a hollow sleeve 7 made of a non-magnetic material rotatably supported in the developing device body e, and a magnetic roller 8 rotatably disposed in the sleeve T and having an agitating magnetic pole.
is provided. In the developer accumulated in the lower right part of the developing device main body 6, due to the magnetic field formed by the magnet roller 8,
It is held on the surface of the sleeve 7 and forms a developing brush. In order to adjust the height of the bristles of the developing brush, the doctor blade 9 is fixedly installed on the developing device main body 6 so that its tip is kept at a predetermined distance from the surface of the sleeve 7.

現像時にには、スリーブ７は矢印入方向、磁石ローラ８
は矢印Ｂ方向に各々回転し、スリーブ７表面に保持され
た現像剤はドクターブレード９で所定穂立ちに調整され
た後、感光体５表面に接触し、感光体５に形成された静
電潜像を現像する。現像後の現像剤は、スリーブ７表面
に接触したスフ−レーバーブレード１０でスリーブ７表
面からかき落される。現像器本体６下邪には、スリーブ
７表面からかき落された現像剤と蓄積現像剤及び供給手
段（図示しない）からの補給現像剤等を攪拌する攪拌部
材１１が設けられている。感光体５に形成された静電潜
像の顕像化が終了した後、スＩＪ　−ブ了は引継き回転
させ、磁石ローラ８の回転を停止させることにより、磁
石ローラ８の磁界により磁石ローラ８とドクターブレー
ド９間で磁気シールが形成され、感光体５表面への現像
剤の供給が停止され、感光体６近傍まで供給されていた
スリーブγ上の現像剤はスリーブ７の回転によりヌクレ
ーバーブレード１０でかき落され、現像器本体ｅ内に回
収される。During development, the sleeve 7 is moved in the direction of the arrow and the magnetic roller 8
are rotated in the direction of arrow B, and the developer held on the surface of the sleeve 7 is adjusted to a predetermined spike by the doctor blade 9, and then comes into contact with the surface of the photoreceptor 5, and the electrostatic latent formed on the photoreceptor 5 is removed. Develop the image. The developer after development is scraped off from the surface of the sleeve 7 by a spray lever blade 10 that is in contact with the surface of the sleeve 7. A stirring member 11 is provided at the bottom of the developing device main body 6 for stirring the developer scraped off the surface of the sleeve 7, the accumulated developer, and the replenishing developer from a supply means (not shown). After the electrostatic latent image formed on the photoreceptor 5 has been visualized, the IJ-blend takes over and rotates, and the rotation of the magnet roller 8 is stopped. A magnetic seal is formed between the doctor blade 8 and the doctor blade 9, and the supply of developer to the surface of the photoconductor 5 is stopped. It is scraped off by the blade 10 and collected into the developing device main body e.

また、隣接する現像器との間には、各々の磁石ローラの
磁界による相互作用を防止する為、隣接し合う磁石ロー
ラ磁極との間の略中央位置に磁石ローラ軸と略平行に延
在せしめたケイ素鋼板（例えば厚さ０．４ｃｍ程度）等
の磁性材より成る磁気シール部材１２が設けられている
。In addition, between adjacent developing devices, in order to prevent interaction due to the magnetic field of each magnetic roller, a developing device is provided that extends approximately parallel to the magnetic roller axis at approximately the center position between the adjacent magnetic roller magnetic poles. A magnetic seal member 12 made of a magnetic material such as a silicon steel plate (for example, about 0.4 cm thick) is provided.

次に、この一実施例の構成における作用を第２図、第３
図を用いて説明する。Next, the operation of the configuration of this embodiment is shown in FIGS. 2 and 3.
This will be explained using figures.

＠２図は隣接する現像器との間に磁気シール部材がない
時の磁石ローラの断側面図を示す。Figure @2 shows a cross-sectional side view of the magnetic roller when there is no magnetic seal member between it and the adjacent developing device.

磁石ローラ７１Ｌ　、　７ｂの対向する側の磁極の磁力
線の向きは、対向し合う磁極の方向に変化し、磁石ロー
ラ７　ａ　ｔ　７　ｂ間に吸引力が発生する。そのため
に、磁石ローラ了ａを回転させると磁石ローラ７ｂも回
転し、非現像時にもかかわらず現像器３内の現像剤が感
光体６表面方向に供給され指定色と異なった色の画像が
得られるとともに飛散等による画像の汚れが発生し、画
像品質の低下を招いていた。また、磁石ローラ７ｂの連
動による問題点を解消するために非現像側の磁石ローラ
を機械的に停止きせるよう構成すると磁石ローラ間の吸
引力以上の回転力を与える必要があり、磁石ローラを回
転させるための起動トルクが増加することによる高出力
の駆動源の採用に伴なう装置の高価格及び大型化等の問
題が生じる。The directions of the lines of magnetic force of the magnetic poles on the opposing sides of the magnetic rollers 71L and 7b change in the direction of the opposing magnetic poles, and an attractive force is generated between the magnetic rollers 7a and 7b. Therefore, when the magnet roller 7b is rotated, the magnet roller 7b is also rotated, and the developer in the developing device 3 is supplied toward the surface of the photoreceptor 6 even when no development is being performed, resulting in an image of a color different from the designated color. At the same time, the image was smeared due to scattering, etc., resulting in a decrease in image quality. Furthermore, if the magnetic roller on the non-developing side is configured to be mechanically stopped in order to solve the problem caused by the interlocking of the magnetic roller 7b, it is necessary to apply a rotational force greater than the attraction force between the magnetic rollers, causing the magnetic roller to rotate. The use of a high-output drive source due to an increase in the starting torque required to drive the engine causes problems such as increased cost and increased size of the device.

しかし、第３図に示すように隣接する現像器内の磁石ロ
ーラ７１Ｌ　Ｉ　７ｂとの間に２個の磁石ローラ了ａ、
７ｂの磁界を受け発生する吸引力の等しい位置（図中で
は略中央位置）に透磁率が高く薄い（厚さ０．４ｍ程度
）ケイ素鋼板にて構成した磁気シール部材１２を配設す
ると、磁気シール部材１２を介して対向し合う各々の磁
極の磁力線の大部分は磁石ローラ内に設けている異極に
向かい、残りの磁力線の大部分は磁気シール部材１２中
を通ってしまい、対向する磁石ローラ７ａ・７ｂ間の吸
引力はほとんどなくなる。また磁石ローラ７λ、７ｂと
磁気シール部材１２との吸引力は、磁気シール部材１２
が薄いため磁石ローラ７！Ｌ。However, as shown in FIG. 3, there are two magnetic rollers 71L and 7b in the adjacent developing device.
When the magnetic seal member 12 made of a thin (approximately 0.4 m thick) silicon steel plate with high magnetic permeability is placed at a position where the attractive force generated by the magnetic field 7b is equal (approximately the center position in the figure), the magnetic Most of the lines of magnetic force of the respective magnetic poles facing each other via the seal member 12 are directed toward different poles provided in the magnet roller, and most of the remaining lines of magnetic force pass through the magnetic seal member 12 and are directed toward the opposite magnets. The suction force between the rollers 7a and 7b is almost eliminated. In addition, the attraction force between the magnetic rollers 7λ, 7b and the magnetic seal member 12 is
Magnet roller 7 because it is thin! L.

７ｂに対する距離が十分あることと磁気シール部材１２
の表面が清めらかであることより非常に弱い力しか働か
ず、磁石ローラを回転させる時の起動トルクの増加も極
めて少なくなる。第４図に示すように同形状で同磁界分
布を形成する２個の磁石ローラを平行に設置し２個の磁
石ローラの略中央位置に薄いケイ素鋼板を設は一方の磁
石ローラを固定させた状態にて他方の磁石ローラの起動
トルクを調べると、第６図に示す結果となり磁気シール
部材１２による磁気シール効果が十分得られた。7b and the magnetic seal member 12.
Because the surface is smooth, only a very weak force is applied, and the increase in starting torque when rotating the magnetic roller is also extremely small. As shown in Figure 4, two magnetic rollers with the same shape and the same magnetic field distribution were installed in parallel, and a thin silicon steel plate was placed approximately in the center of the two magnetic rollers to fix one of the magnetic rollers. When the starting torque of the other magnetic roller was examined in this state, the results shown in FIG. 6 were obtained, indicating that a sufficient magnetic sealing effect by the magnetic sealing member 12 was obtained.

尚、現像器構成の一実施例を示す第１図において、磁石
ローラ８が固定でスリーブ７が回転する現像器にも適用
でき、磁気シール部材１２を介在することにより各々の
磁石ローラの磁界による相互作用を防止できる。In addition, in FIG. 1 showing an example of the structure of the developing device, it can also be applied to a developing device in which the magnet roller 8 is fixed and the sleeve 7 rotates, and by interposing the magnetic seal member 12, the magnetic field of each magnet roller is removed. Interactions can be prevented.

また、磁気シール部材１２として、棒状及び円筒状の磁
性部材で構成しても同様の作用が得られる。Further, the same effect can be obtained even if the magnetic seal member 12 is composed of a rod-shaped or cylindrical magnetic member.

また、磁石ローラ表面に略平行に形成した磁気シール部
材１２及び各々の磁石ローラ間に介在する現像器本体６
の少なくとも一方側を磁気シール部材で形成しても同様
の作用が得られる。Further, a magnetic seal member 12 formed substantially parallel to the surface of the magnet roller and a developing device main body 6 interposed between each magnet roller.
A similar effect can be obtained by forming at least one side of the magnetic seal member with a magnetic sealing member.

発明の効果 以上のように構成することにより、複数個の現像器を近
接して並設させることができるので小型の現像手段構成
が得られ、装置の小型化が図れる。Effects of the Invention By configuring as described above, a plurality of developing devices can be arranged in close proximity to each other, so a compact developing means structure can be obtained, and the device can be downsized.

特に磁気シール部材として高透磁率のケイ素鋼板で構成
することにより薄い磁気シール部材で磁気シールでき、
現像手段の小型化が容易になる。また、磁石ローラが回
転する現像器を有する現像手段構成に２いては、磁石ロ
ーラの相互作用を防止できるとともに磁石ローラの起動
トルクの増加が極めて少ない状態にて現像手段を小型化
でき、磁石ローラの駆動源を高出力のものにする必要が
なく装置の低価格及び小型化が図れる。また、隣接する
現像器内の磁石ローラ磁極の磁界を受け発生する吸引力
の等しい位置に磁気シールド板を介在させることにより
磁気シール効果及び磁石ローラの起動トルクに対する効
果が十分得られ、現像手段がより小型化できる。In particular, by configuring the magnetic seal member with a silicon steel plate with high magnetic permeability, magnetic sealing can be achieved with a thin magnetic seal member.
It becomes easy to downsize the developing means. In addition, in the developing means configuration 2 having a developing device in which the magnetic roller rotates, interaction between the magnetic rollers can be prevented, and the developing means can be downsized with an extremely small increase in the starting torque of the magnetic roller. There is no need to use a high-output drive source, and the device can be made smaller and cheaper. In addition, by interposing a magnetic shield plate at a position where the attraction force generated by the magnetic field of the magnetic roller magnetic poles in adjacent developing units is equal, a sufficient magnetic sealing effect and effect on the starting torque of the magnetic roller can be obtained, and the developing means can be Can be made more compact.

更に、感光ドラム等の感光体表面に沿って複数個の現像
手段を並設せしめた現像手段を有する装置では、現像手
段と対向する感光ドラム表面局長が少なくて良いので感
光ドラムの小型化が得られ装置の低価格化及び小型化が
図れる。Furthermore, in an apparatus having a developing means in which a plurality of developing means are arranged in parallel along the surface of a photoreceptor such as a photoreceptor drum, the photoreceptor drum surface area facing the developing means may be reduced, so that the size of the photoreceptor drum can be reduced. As a result, the cost and size of the device can be reduced.

また、感光体移送路沿における各プロセス手段の配置が
し易くなるとともに不要な混色が生じない高品質の画像
を得ることができる。Further, it becomes easier to arrange each process means along the photoreceptor transport path, and high-quality images can be obtained without unnecessary color mixture.

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

第１図は、本発明の一実施例における画像形成装置の要
部断側面図、第２図、第３図は本発明の詳細な説明する
説明図、第４図及び第５図は本発明の作用の効果を示す
説明図でらる。 １・・・・・・現像手段、２〜４・・・・・・現像器、
５・・・・・・感光体、６・・・・・・現像器本体、７
・・・・・・スリーブ、８・・・・・・磁石ローラ、９
・・・・・・ドクターブレード、１０・・・・・・スク
ーレーパーブレード、１１・・・・・・攪拌部材、１２
・・・・・・磁気シール部材。 代理人の氏名　弁理士　中　尾　敏　男　はか１名！・
・・現イ１ｋ　テラ父。 ８・・・磁石υ−り ２・・・　Ｆ゛ククー２′シー ｒｔ・・−′Ｊ！、拌部材 ／２．−、でえ気シー１Ｖ４０材 第　２　図 第３図FIG. 1 is a sectional side view of a main part of an image forming apparatus according to an embodiment of the present invention, FIGS. 2 and 3 are explanatory diagrams explaining the present invention in detail, and FIGS. This is an explanatory diagram showing the effect of the action. 1...Developing means, 2-4...Developing device,
5...Photoreceptor, 6...Developer body, 7
... Sleeve, 8 ... Magnet roller, 9
...Doctor blade, 10...Scooper blade, 11...Stirring member, 12
...Magnetic seal member. Name of agent: Patent attorney Toshi Nakao (only 1 person!)・
...Currently 1k Terra's father. 8... Magnet υ-ri 2... F゛kuku 2' sea rt...-'J! , stirring member/2. -, Deke Sea 1V40 material Fig. 2 Fig. 3

Claims (4)

【特許請求の範囲】[Claims] （１）スリーブ内に複数の磁極を有する磁石ローラを配
置し、前記スリーブ及び前記磁石ローラのうち少なくと
も一方を回転可能に構成した現像器と、前記現像器を複
数個並設し現像時には少なくとも１個の前記現像器の現
像部が記録体に対向可能に配置した現像手段と、隣接し
合う前記現像器内の前記各スリーブの間に前記磁石ロラ
の軸方向に延在せられ、対向し合う前記磁石ローラ磁極
の磁界を磁気シールする磁気シール部材とを備えたこと
を特徴とする画像形成装置。(1) A developing device in which a magnetic roller having a plurality of magnetic poles is disposed in a sleeve, and at least one of the sleeve and the magnetic roller is configured to be rotatable, and a plurality of the developing devices are arranged side by side, and at least one The developing units of the developing units are arranged so as to be able to face the recording medium, and the developing units extend in the axial direction of the magnetic roller between the sleeves in the adjacent developing units, and are opposed to each other. An image forming apparatus comprising: a magnetic seal member that magnetically seals the magnetic field of the magnetic roller magnetic pole. （２）少なくとも磁石ローラが回転可能である現像器を
有する現像手段を備えた特許請求の範囲第１項記載の画
像形成装置。(2) The image forming apparatus according to claim 1, further comprising a developing means having a developing device in which at least a magnet roller is rotatable. （３）磁気シール部材を、隣接し合う磁石ローラ磁極の
磁界を受け発生する吸引力の略等しい位置に介在せしめ
た特許請求の範囲第１項記載の画像形成装置。(3) The image forming apparatus according to claim 1, wherein the magnetic seal member is interposed at a position where the attraction forces generated by the magnetic fields of adjacent magnet roller magnetic poles are substantially equal. （４）磁気シール部材が、厚さ０．４ｍｍ程度のケイ素
鋼板で構成された特許請求の範囲第１項記載の画像形成
装置。(4) The image forming apparatus according to claim 1, wherein the magnetic seal member is made of a silicon steel plate with a thickness of about 0.4 mm.