JP3711640B2

JP3711640B2 - Color image forming apparatus

Info

Publication number: JP3711640B2
Application number: JP19047796A
Authority: JP
Inventors: 哲羽根田; 久喜永瀬; 宏行時松; 正泰小野寺; 州太 ▲浜▼田; 俊英三浦
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 1996-07-19
Filing date: 1996-07-19
Publication date: 2005-11-02
Anticipated expiration: 2016-07-19
Also published as: JPH1039587A

Description

【０００１】
【発明の属する技術分野】
本発明は、電子写真方式のカラー複写機や記録装置と言ったカラー画像形成装置に関し、特に、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体の周囲に配置した複数の現像器とを備えたカラー画像形成装置に関する。
【０００２】
【従来の技術】
上述のようなカラー画像形成装置は、複数の像露光手段を像形成体の内部に収容するから、像形成体に比較的周面長の短い小径のものを用いることができて、装置を小型化することができ、像露光をトナーの付着しない像形成体の内周面に入射するから第２色目以降の静電像も第１色目の静電像と同様の鮮明さで形成できて、色バランスの良いカラー画像を形成できると言う特長がある。しかし反面、従来のものには、コンパクトな構成となるため、組立、分解、保守等に手間が掛かかるし、像形成体と内部の像露光手段の支持体が完全に離れているため、像形成体内周面と複数の像露光手段の距離を一定にして像形成体の回転を円滑にするのが難しくて、形成されるカラー画像に色ずれが出易いと言う問題がある。
【０００３】
【発明が解決しようとする課題】
本発明は、上述のカラー画像形成装置の問題を解消するためになされたものであり、像形成体内部に複数の像露光手段を収容したカラー画像形成装置において、像形成体内周面と複数の像露光手段の距離が一定に保たれて、像形成体を円滑に回転することができ、したがって色ずれのない鮮明なカラー画像を容易に形成できる装置の提供を第１の目的とし、さらに組立、分解、保守等を容易に行うことができる装置の提供を第２の目的とし、またさらに像形成体と複数の像露光手段の一体化を軽量化した装置の提供を第３の目的とする。
【０００４】
【課題を解決するための手段】
本発明は、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体の周囲に配置した複数の現像器とを備えたカラー画像形成装置において、特許請求の範囲の請求項１の、前記光学系支持手段を構成する、軸に固定された一対のブラケットは、互いに対向する近い部分である露光手段固定部に像露光手段が固定され、対向しない互いに離れた部分である像形成体軸受支持部に前記像形成体が回転自在に支持されており、前記像形成体軸受支持部の径が前記露光手段固定部の径より大きく、該像形成体軸受支持部により一端側の外周に受動歯車を有する前記像形成体を回転自在に支持し、該像形成体軸受支持部より軸方向外側に突出させた前記軸を装置本体側板に保持させて装置本体に装着されることを特徴とする構成によって、前記第１及び第２の目的を達成する。
【０００５】
すなわち請求項１の装置は、複数の像露光手段を取り付けた光学系支持手段が像形成体軸受支持部で像形成体を回転自在に支持するから、像形成体内周面と複数の像露光手段の距離が一定に保たれて、像形成体を円滑に回転することができ、したがって色ずれのない鮮明なカラー画像を容易に形成できる第１の目的を達成する。また像形成体軸受支持部の径が露光手段固定部の径より大きいことによって、複数の像露光手段を固定した光学系支持手段と像形成体の組み立て分解が容易にでき、さらに像形成体が一端側の外周に受動歯車を有することによって、像形成体が一体化された光学系支持手段を装置本体側板に対して係脱させたときに受動歯車を装置本体側の駆動歯車と係脱させる組み立て分解が容易にできる第２の目的を達成する。
【０００６】
請求項１の装置に請求項２の、前記装置本体側板に保持される前記光学系支持手段の軸の外径が１０〜３０ｍｍの範囲にあることを特徴とする構成が加わることによって、像形成体を一体化した光学系支持手段を装置本体側板に支持させる構造をコンパクトにでき、また請求項１または請求項２の装置に請求項３の、前記装置本体側板に保持される前記光学系支持手段の軸が前記像形成体軸受支持部よりも軸方向外側に突出した部分の長さが２０〜１００ｍｍの範囲にあることを特徴とする構成が加わることによって、像形成体を一体化した光学系支持手段を容易に装置本体側板に安定確実に支持させるようにでき、またさらに請求項４の、前記像露光手段への電気配線を前記受動歯車の位置する側とは反対側から行うことを特徴とする構成が加わることによって、像露光手段の配線処理が特に容易になると共に、像形成体の受動歯車側の装置本体側板に像形成体への回転伝達手段を設けることが容易になって、光学系支持手段の装置本体側板に対する組み立て分解が特に容易に行われるようにできる。
【０００７】
また本発明は、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体の周囲に配置した複数の現像器とを備えたカラー画像形成装置において、請求項５の、前記光学系支持手段を構成する、軸に固定された一対のブラケットは、互いに対向する近い部分である露光手段固定部に像露光手段が固定され、対向しない互いに離れた部分である像形成体軸受支持部に前記像形成体が回転自在に支持されており、前記像形成体軸受支持部の径が前記露光手段固定部の径より大きくて肉抜き孔または溝のある像形成体軸受支持部を有し、該像形成体軸受支持部により一端側の外周に受動歯車を有する前記像形成体を回転自在に支持し、該像形成体軸受支持部より軸方向外側に突出させた前記軸を装置本体側板に保持させて装置本体に装着されることを特徴とする構成によって、前記第１乃至第３の目的を達成する。
【０００８】
すなわち請求項５の装置は、光学系支持手段の像形成体軸受支持部に肉抜き孔または溝を設けて像形成体を一体化した光学系支持手段を軽量化する第３の目的を達成した以外は請求項１の装置と同じであるから、第１と第２の目的も請求項１の装置と同様に達成する。
【０００９】
また請求項５の装置に請求項６の、前記像形成体軸受支持部の外径が３０〜１００ｍｍの範囲にあることを特徴とする構成が加わることによって、像形成体を一体化した光学系支持手段の大型化を制限し、且つ像形成体軸受支持部に軽量化のため、あるいは像露光手段の電気配線や像形成体等の冷却風を通すための肉抜き孔または溝を設けることが容易になり、請求項５の装置の目的達成を助長する。
【００１０】
また請求項５または請求項６の装置に請求項７の、前記像形成体軸受支持部の肉抜き孔または溝に前記像露光手段の電気配線を通すようにしたことを特徴とする構成、さらには請求項８の、前記像露光手段の電気配線は前記像形成体の受動歯車が位置する側とは軸方向に反対側で電源に接続されることを特徴とする構成が加わることによって、像形成体と光学系支持手段の一体化における像露光手段の配線処理が容易になり、さらには像形成体を一体化した光学系支持手段の装置本体側板に対する係脱が容易になるから一層前記第２の目的が達成される。
【００１１】
また、請求項５乃至８の装置に請求項９の、前記像形成体軸受支持部の肉抜き孔または溝に空気流を通すことを特徴とする構成、さらに請求項１０の、前記空気流は前記像形成体の受動歯車が位置する側とは軸方向に反対側から前記光学系支持手段の前記像形成体軸受支持部の肉抜き孔または溝に流入することを特徴とする構成、またさらに請求項１１の、前記像形成体軸受支持部の肉抜き孔または溝に冷却フィンを設けたことを特徴とする構成が加わることによって、像露光手段を内部に有する像形成体の温度上昇を空気流によって防止できるから、像形成体の回転、帯電、静電像及びトナー像形成が安定して行われるようになって、色ずれのない鮮明なカラー画像を形成できると言う前記第１の目的達成を助長する。
【００１２】
また本発明は、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体の周囲に配置した複数の現像器とを備えたカラー画像形成装置において、請求項１２の、前記光学系支持手段を構成する、軸に固定された一対のブラケットは、互いに対向する近い部分である露光手段固定部に像露光手段が固定され、対向しない互いに離れた部分である像形成体軸受支持部に前記像形成体が回転自在に支持されており、前記像形成体軸受支持部の径が前記露光手段固定部の径より大きく、前記光学系支持手段の軸は、中空であり、該像形成体軸受支持部により一端側の外周に受動歯車を有する前記像形成体を回転自在に支持し、前記像形成体軸受支持部より軸方向外側に突出させた中空軸を装置本体側板に保持させて装置本体に装着されることを特徴とする構成によって、前記第１乃至第３の目的を達成する。
【００１３】
すなわち請求項１２の装置は、光学系支持手段を中空にして像形成体を一体化した光学系支持手段を軽量化する第３の目的を達成した以外は請求項１の装置と同じであるから、第１と第２の目的も請求項１の装置と同様に達成する。
【００１４】
また請求項１２の装置に請求項１３の、装置本体側板に支持される前記光学系支持手段の中空軸の外径が３０〜８０ｍｍ範囲にあることを特徴とする構成が加わることによって、中空軸部の強度を十分に保って中空孔を軽量化以外にも利用し易くする。また請求項１２乃至１３の装置に請求項１４の、前記光学系支持手段の中空軸の中空孔に前記像露光手段の電気配線を通すようにしたことを特徴とする構成、さらに請求項１５の、前記像露光手段の電気配線は前記像形成体の受動歯車が位置する側とは反対側で電源に接続されることを特徴とする構成が加わることによって、像露光手段の配線処理が容易になり、さらに像形成体の受動歯車側の装置本体側板に像形成体への回転伝達手段を設けることが容易になって、光学系支持手段の装置本体側板に対する組み立て分解が容易に行われる前記第２の目的達成を助長する。
【００１５】
また請求項１２乃至１５の装置に請求項１６の、前記光学系支持手段の中空軸の中空孔に空気流を通すことを特徴とする構成、さらに請求項１７の、前記空気流は前記像形成体の前記受動歯車が位置する側とは反対側から前記光学系支持手段の中空軸の中空孔に流入することを特徴とする構成、またさらに請求項１８の、前記光学系支持手段の中空軸部の中空孔に冷却フィンを設けたことを特徴とする構成が加わることによって、像露光手段を内部に有する像形成体の温度上昇を空気流によって防止できるから、像形成体の回転、帯電、静電像及びトナー像形成が安定して行われるようになって、色ずれのない鮮明なカラー画像を形成できると言う前記第１の目的達成を助長する。
【００１６】
また本発明は、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体周囲に配置した複数の現像器とを備えたカラー画像形成装置において、請求項１９の、前記光学系支持手段は、前記像露光手段を取り付ける露光手段固定部が像露光手段の両端部を固定する固定部分の間を空腔に形成して該空腔に像露光手段の電気配線の結線部を臨ませ、該露光手段固定部より軸方向外側に像形成体軸受支持部を有し、該像形成体軸受支持部により前記像形成体を回転自在に支持し、該像形成体軸受支持部より軸方向外側に突出させた前記軸を装置本体側板に保持させて装置本体に装着されることを特徴とする構成によって、前記第１乃至第３の目的を達成する。
【００１７】
すなわち請求項１９の装置は、請求項１，５，１２の装置と同様に、複数の像露光手段を支持した光学系支持手段が像形成体と一体化して装置本体側板により支えられる構成であるから、像形成体内周面と複数の像露光手段の距離が一定に保たれて、色ずれのない鮮明なカラー画像を容易に形成できると言う第１の目的及び像形成体を一体化した光学系支持手段の装置本体に対する組立、分解、保守等が容易と言う第２の目的を達成し、また光学系支持手段が複数の像露光手段の両端部を固定した固定部分の間に空腔を形成していることにより、像形成体を一体化した光学系支持手段を軽量化する第３の目的を達成する。さらに光学系支持手段に形成した空腔に像露光手段の配線の結線部を臨ませているから、像露光手段の配線を容易に行うことができ、像形成体と一体化した光学系支持手段の組立、分解、保守等を容易にすると言う第２の目的も達成する。
【００１８】
また本発明は、複数の像露光手段を取り付けた光学系支持手段と、内部に前記像露光手段を収容したドラム状の像形成体と、該像形成体の周囲に配置した複数の現像器とを備えたカラー画像形成装置において、請求項２０の、前記光学系支持手段を構成する、軸に固定された一対のブラケットは、互いに対向する近い部分である露光手段固定部に像露光手段が固定され、対向しない互いに離れた部分である像形成体軸受支持部に前記像形成体が回転自在に支持されており、前記像形成体軸受支持部の径が前記露光手段固定部の径より大きく、電気配線の結線部が端面または側面に位置した前記像露光手段を固定し、前記像形成体軸受支持部より軸方向外側に突出させた前記軸を装置本体側板に保持させて装置本体に装着されることを特徴とする構成によって、前記第１及び第２の目的を達成する。
【００１９】
すなわち請求項２０の装置は、複数の像露光手段を支持した光学系支持手段が像形成体と一体化して装置本体側板により支えられる請求項１，５，１２，１９の装置と同様の構成であるから、同様に前記第１及び第２の目的を達成し、また光学系支持手段が電気配線の結線部を端面または側面に位置させた像露光手段を外周面に乗せた状態で固定しているから、像露光手段の配線を容易に行うことができ像形成体と一体化した光学系支持手段の組立、分解、保守等を容易にする第２の目的も達成する。
【００２０】
また請求項１９及び請求項２０の装置に請求項２１の、前記像形成体軸受支持部に支持された前記像形成体が一端側の外周に受動歯車を有することを特徴とする構成が加わることよって、装置本体側に設けられる駆動手段と像形成体の受動歯車の係合離脱が容易になるから、像形成体と一体化した光学系支持手段の装置本体側板に対する係脱が容易になると言う第２の目的も達成される。
【００２１】
また請求項２１の装置に請求項２２の、前記像露光手段の電気配線が前記光学系支持手段の前記像形成体軸受支持部の支持する軸受の内側を通って前記像露光手段の結線部と電源とを接続することを特徴とする構成、さらには請求項２３の、前記像露光手段の電気配線の電源が前記像形成体の受動歯車が位置する側とは軸方向反対側にあることを特徴とする構成が加わることによって、像形成体と光学系支持手段の一体化における像露光手段の配線処理が容易になり、さらには像形成体を一体化した光学系支持手段の装置本体側板に対する係脱が容易になるから一層前記第２の目的達成が助長される。
【００２２】
【発明の実施の形態】
以下、図面を参照して本発明の実施の形態を説明する。
【００２３】
図１は本発明に係るカラー画像形成装置の例を示す概要構成断面図、図２は像形成体を一体化した光学系支持手段の取り付け状態を示す部分正面図、図３は請求項１乃至１１及び請求項２０乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図、図４は請求項１２乃至１８の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図、図５は請求項１９及び請求項２１乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図、図６は請求項２０乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図である。
【００２４】
図において、１０はドラム状の像形成体であり、像形成体１０は、光学ガラスもしくは透明アクリル樹脂等の透明部材から成る円筒状基体の外周に透明導電層，有機感光体層（ＯＰＣ）を塗布等により設けて感光体ドラム部分を形成し、感光体ドラム部分の両端部の内径に、それぞれ内周に軸受１０Ｃが嵌合する端部環１０Ａと外周に受動歯車であるドラム歯車１０Ｇを有する端部歯車環１０Ｂを一体的に嵌着して構成されている。ここで、ドラム歯車１０Ｇは外歯車に限らず内歯にしてもよいし、端部環１０Ａや端部歯車環１０Ｂが感光体ドラム部分の外径に嵌着したものでも、感光体ドラム部分と一体に形成されたものでもよいことは勿論である。
【００２５】
１１Ｙ〜１１Ｋはスコロトロンコロナ放電器を用いた帯電器であり、１２Ｙ〜１２Ｋは像形成体１０の軸方向に平行に配列したＬＥＤと結像素子（商品名：セルフォックレンズ）とから構成されたライン状の像露光手段である。像露光手段１２Ｙ〜１２Ｋには別体の例えば画像読み取り装置によって読み取られた分解色等の色別画像信号がメモリより順次取り出されてそれぞれ電気信号として入力される。
【００２６】
像形成体１０と像露光手段１２Ｙ〜１２Ｋはユニットとして一体的に組み込まれている。すなわち、ユニット軸３１とその外径に嵌合し固定された前後一対のブラケット３２，３３が光学系支持手段を構成していて、ブラケット３２，３３の互いに近い部分の外径に像露光手段１２Ｙ〜１２Ｋが固定され、ブラケット３２，３３の互いに離れた部分の外径に像形成体１０が回転自在に支持される。したがって、ブラケット３２，３３の互いに近い部分が露光手段固定部３２０，３３０であり、ブラケット３２，３３の互いに離れた部分が像形成体軸受支持部３２１，３３１である。
【００２７】
像形成体１０は、両端の端部環１０Ａと端部歯車環１０Ｂにそれぞれ嵌合する軸受１０Ｃがブラケット３２，３３の像形成体軸受支持部３２１，３３１にそれぞれ嵌合することによって、回転自在に支持される。それより前に像露光手段１２Ｙ〜１２Ｋは、像形成体１０の感光体ドラム部分内面に対する距離が所定の位置関係となるように、それぞれの両端部が貼付部材３４を介して調節され、ブラケット３２，３３の露光手段固定部３２０，３３０に接着により固定される。
【００２８】
以上により請求項１，５，１２，１９，２０等に記載の像形成体と一体化した光学系支持手段が構成され、それによって像形成体１０に対する像露光手段１２Ｙ〜１２Ｋの関係位置を精度よく設定できるから、像露光手段１２Ｙ〜１２Ｋにより像形成体１０にそれぞれ形成する静電潜像の位置を正確に合わすことが容易にでき、色ずれのないカラー画像を容易に形成できる。
【００２９】
図３乃至図６の例では、像露光手段１２Ｙ〜１２Ｋの両端部を固定している露光手段固定部３２０，３３０間が請求項１９に記載の空腔３０を形成していて、それによりユニットを軽量化しており、また図５の例では、像露光手段１２Ｙ〜１２Ｋを駆動するための電気配線１２１の結線部１２２を空腔３０側に設けることによって電気配線１２１の接続を容易にしている。それに対して、請求項１，５，１２，２０の構成のように、空腔３０による軽量化を考えなければ、ブラケット３２，３３が一体に繋がった形のブラケットの外表面に像露光手段１２Ｙ〜１２Ｋが貼り付けられていて、図３や図６のように像露光手段１２Ｙ〜１２Ｋが電気配線１２１の結線部１２２を端面または側面に配設した請求項２０の構成にしても、像露光手段１２Ｙ〜１２Ｋの電気配線１２１との接続は容易にできる。
【００３０】
ユニット軸３１は、像形成体１０や像露光手段１２Ｙ〜１２Ｋを保持したブラケット３２，３３が両側板部３５Ａと連結梁部３５Ｂとから成るコの字状ブラケット３５の両側板部３５Ａ間に位置して、両端部が両側板部３５Ａから突出するように、両側板部３５Ａに回転可能に装着される。そしてコの字状ブラケット３５の一方の側板部３５Ａの外側に突出したユニット軸３１の端部には位相ピン３６が植設され、他方の側板部３５Ａの外側に突出した端部には後に螺合する先端部ナット３７により前面板３８が締め付け固定される。
【００３１】
図２乃至図６の例では、上述のようにコの字状ブラケット３５が取り付けられてユニットが構成され、コの字状ブラケット３５は、後述のように、ユニットを装置本体内に装着するのに利用される他、ユニットを床面に置く際に連結梁部３５Ｂを床面上に当てる底面とすることで、像形成体１０や像露光手段１２Ｙ〜１２Ｋを床面に接触させることのない置き台としても利用される。
【００３２】
図３，５，６の例は、ユニット軸３１が中実軸で、それに固設されたブラケット３２、３３の像形成体軸受支持部３２１，３３１に像形成体１０が回転自在に支持されている請求項１，５，１９，２０の構成を示しており、また図３及び図６は請求項２０の構成のうちの像露光手段１２Ｙ〜１２Ｋの結線部１２２がそれぞれ端面及び側面に配設されている例を示している。また図５は先に述べたように請求項１９の構成を示している。そして図５及び図６の例においては、像露光手段１２Ｙ〜１２Ｋの結線部１２２に接続された電気配線１２１は、ブラケット３２、３３の露光手段固定部３２０，３３０に固定された像露光手段１２Ｙ〜１２Ｋの並びの間とブラケット３２の像形成体軸受支持部３２１の軽量化を兼ねている肉抜き孔または溝（以下単に、肉抜き孔と言う）３２Ａを通して像形成体１０外に出され、さらにコの字状ブラケット３５の側板部３５Ａの切欠部３５Ｃとさらに前面板３８の適当に設けられた溝または孔を通って先端の接続端子を電源に接続する請求項２２及び２３の構成にしている。一方図３の例においては、像露光手段１２Ｙ〜１２Ｋの結線部１２２が端面にあるから、像露光手段１２Ｙ〜１２Ｋの並びの間に隙間がなくても配線を同様にユニットの外に出して電源に接続できる。いずれの例においても配線処理が容易でユニットの着脱が容易にできる。
【００３３】
図４の例では、ユニット軸３１は請求項１２の構成の如く中空軸に形成されてユニットを軽量化する。また像露光手段１２Ｙ〜１２Ｋの電気配線１２１は、像露光手段１２Ｙ〜１２Ｋのユニット軸３１側に対向した裏面に設けられた結線部１２２からユニット軸３１の管壁に設けた孔３１Ａを通して中空孔３１Ｈ内に入り、ブラケット３２の前面板３８側のユニット軸３１の管壁に設けた孔３１Ｂを通して中空孔３１Ｈから出て、コの字状ブラケット３５の側板部３５Ａの切欠部３５Ｃとさらに前面板３８の適当に設けられた溝または孔を通って先端の接続端子を電源に接続する請求項１４及び１５の構成にしている。これによって、ユニットを装置本体に対し着脱する際の配線の断接が容易になるから、ユニットの着脱も容易になる。
【００３４】
中空のユニット軸３１のコの字状ブラケット３５から突出する両端部分の外径は請求項１３の構成の３０〜８０ｍｍの範囲にあることが、十分な強度を保って電気配線１２１を容易に通すことができる中空孔を設けることができ、しかも画像形成装置を大型化させないで済むので好ましい。また、像露光手段１２Ｙ〜１２Ｋの駆動により像形成体１０の内部の温度が上昇するのを防止するように、ユニット軸３１の中空孔３１Ｈに空気流を流す請求項１６の構成にでき、それは前面板３８から流す請求項１７の構成が流し込みダクトを像形成体１０や現像器の現像ローラ等の駆動手段に関係なく接続し得るので好ましい。さらに冷却効率を高めるために、中空孔３１Ｈまたはさらにユニット軸３１の外径等に冷却フィンを設ける請求項１８の構成も好ましい。このような冷却手段を設けることで、安定した画像形成が行われるようになる。
【００３５】
図３乃至図６の例でも、電気配線１２１の接続端子の電源への接続はユニットの装置本体への装着後となるが、電源の接続部が前面板３８より内側にあるときは、前面板３８を取り付ける前のユニットを装置本体内に挿入した段階で行うことになる。その場合は前面板３８に配線を通す溝や孔は必要ない。また図示例とは反対に、配線を位相ピン３６の植設側に伸ばして装置本体のユニット挿入方向の奥側板７０Ｂ側に設けた電源の接続端子に接続するようにもできるが、その場合はユニットの挿入完了と共に接続が行われるように、ユニットの接続端子はユニット軸３１に固定して設けることが必要になる。すなわち、電気配線１２１は像形成体１０のドラム歯車１０Ｇの側とは反対側に伸びて電源と接続する請求項４，８，１５，２３の構成の図示例の方が好ましい。
【００３６】
また図３，５，６のいずれの例においても、光学系支持手段のブラケット３２、３３の像形成体１０の軸受１０Ｃを支持する像形成体軸受支持部３２１，３３１の径が像露光手段１２Ｙ〜１２Ｋを固定する露光手段固定部３２０，３３０の径よりも大きい請求項１の構成、さらには像形成体軸受支持部３２１，３３１に肉抜き孔３２Ａ，３３Ａを設けた請求項５の構成であることが、像露光手段１２Ｙ〜１２Ｋを取り付けた光学系支持手段に像形成体１０を一体化するのを容易にするし、また像形成体軸受支持部３２１，３３１に請求項４，７，８，２２、２３の構成の電気配線１２１の通路となる肉抜き孔３２Ａ，３３Ａを設け易くし、さらには肉抜き孔３２Ａ，３３Ａを請求項９，１０の形態の冷却風の通路にし易くするので、好ましい。
【００３７】
ブラケット３２，３３の像形成体軸受支持部３２１，３３１に肉抜き孔３２Ａ，３３Ａを設ける請求項５の構成においては、そのフランジ部分の外径が請求項６の構成の３０〜１００ｍｍであることが、肉抜き孔３２Ａ，３３Ａを軽量化の目的以外に、請求項７や８の構成のように像露光手段１２Ｙ〜１２Ｋの電気配線１２１通すのに利用できるし、また請求項９や１０の構成のように空気流を通すのにも利用できて、しかも装置を大型化させないで済むので、好ましい。そして像形成体軸受支持部３２１，３３１の肉抜き孔３２Ａ、３３Ａに空気流を通して像形成体１０の内周面や像露光手段１２Ｙ〜１２Ｋ等を冷却するのも、像形成体１０のドラム歯車１０Ｇ側と反対側すなわち前面板３８側から像形成体軸受支持部３２１の肉抜き孔３２Ａに空気が流入する請求項１０の構成にするのが、流入側に像形成体駆動手段のような発熱源等がないので好ましい。
【００３８】
肉抜き孔３２Ａ，３３Ａに空気流を通す場合は、肉抜き孔３２Ａ，３３Ａに冷却フィンを設ける請求項１１の構成とするのが、冷却効率の上で好ましい。またこれら肉抜き孔３２Ａ，３３Ａは、解放しておくと飛散したトナーが像形成体１０の内部に入り込んで内周面や像露光手段１２Ｙ〜１２Ｋの発光表面を汚染するようになるので、フィルタにより塞いでトナー等の侵入を防止するのが好ましい。
【００３９】
一方肉抜き孔を必要としない請求項１の形態においては、ユニット軸３１のコの字状ブラケット３５から突出して装置本体両側板７０Ａ，７０Ｂに軸受支持される部分の外径が請求項２の構成の１０〜３０ｍｍであることがユニットの後述する固定構造をコンパクトで、しかも十分な強度にできるので好ましく、またコの字状ブラケット３５から突出した長さが請求項３の構成の２０〜１００ｍｍであることが、安定した固定ができて、装置を大型化させないで済むので好ましい。
【００４０】
図２乃至図６において、装置本体へのユニットの装着は以下のようになされる。すなわち、ユニットは、ユニット軸３１の位相ピン３６側を先頭にして、装置本体の手前側板７０Ａに設けた挿入孔７０Ａ１から、コの字状ブラケット３５の連結梁部３５Ｂを装置本体の手前、奥両側板７０Ａ、７０Ｂの間に設けた案内支持レール７１に係合させて装置本体内に送り込まれ、像形成体１０のドラム歯車１０Ｇを奥側板７０Ｂ側に設置された不図示のモータからの減速駆動歯車６２に噛合させると共に、位相ピン３６を装置本体の奥側板７０Ｂに設けた軸受座７２に形成された位置決めテーパー溝に係合させ、その状態で前面板３８をネジ止めにより装置本体の手前側板７０Ａに固定されて装着される。それによって、像形成体１０と像露光手段１２Ｙ〜１２Ｋが正確な位置と位相で装置本体内に設置される。
【００４１】
なお図２の例では、前面板３８を装置本体の手前側板７０Ａに固定するのに、前面板３８に設けた複数の基準孔Ｈ１に手前側板７０Ａの備える基準ピンＰ２を係合させて前面板３８の位置決めを行うようにしているから、最初に前面板３８を装置本体の手前側板７０Ａに固定するときは、ユニット軸３１と先端部ナット３７で前面板３８を回らないように締め付け固定するのを基準孔Ｈ１と基準ピンＰ２を係合させた後に行う。前面板３８には帯電器１１Ｙ〜１１Ｋの挿入口３８Ａが設けられている。
【００４２】
帯電器１１Ｙ〜１１Ｋは、それぞれ受電端子側を先頭に手前側板７０Ａに取り付けた前面板３８の挿入口３８Ａから装置本体内に挿入し、手前、奥両側板７０Ａ、７０Ｂの間に設けた案内支持レール７３の案内で受電端子が奥側板７０Ｂに設けた給電端子と接続するように送り込んだ後、挿入口３８Ａに押し蓋３９をネジ止めすることによって、像形成体１０に対し所定の間隔位置を保ち作動可能に設置される。従ってユニットを装置本体から取り外すのは、先に帯電器１１Ｙ〜１１Ｋを挿入口３８Ａから取り出した後に、前面板３８を手前側板７０Ａから外して引き出すことになる。この他、ユニットの取り外しに先立って、像形成体１０の周面に対する後述の現像器１３Ｙ〜１３Ｋ、中間転写ベルト１４ならびにクリーニング装置１００のクリーニングブレードの各圧接作用を従来公知の手段等で解除して１ｍｍ程度以上は退避させて置くのが必要であることは言うまでもない。
【００４３】
現像器１３Ｙ〜１３Ｋはそれぞれイエロー（Ｙ），マゼンタ（Ｍ），シアン（Ｃ）及び黒色（Ｋ）のトナーを用いた現像剤で現像するものであり、手前側板７０Ａ側から装置本体内に挿入されて手前、奥両側板７０Ａ、７０Ｂ間に設けた案内支持レール７４に従って係止案内７５で止められるまで送り込まれ、次いで図３乃至図６に示した例では、接離操作ハンドル４０で偏心溝カム４１を回動させて案内支持レール７４の下面側に支持された偏心溝カム４１と係合する接離作用軸４２を軸方向に変位させ、それにより該軸に設けたバネで現像器１３Ｙ〜１３Ｋをそれらの現像スリーブ１３０の両側の回転自在のスペーサーローラが像形成体１０に圧接するように押すことで装置本体内に設置される。それによって現像スリーブ１３０と一体のスリーブ歯車１３３〜１３６に奥側板７０Ｂ側に設置された不図示のモータからの減速駆動歯車５３〜５６が噛合する。以上の逆の操作で現像器１３Ｙ〜１３Ｋの像形成体１０に対する圧接解除や装置本体からの取り出しが行われる。
【００４４】
設置された現像器１３Ｙ〜１３Ｋは、図１に示したように、像形成体１０の回転中心を通る垂線の左右に略対称的かつ回転中心を通る水平線の上下に別れる位置を占め、現像剤層搬送ローラである現像スリーブ１３０が像形成体１０と所定の間隙を保って同じ表面移動方向で回転し、それぞれ帯電器１１Ｙ〜１１Ｋによる帯電と像露光手段１２Ｙ〜１２Ｋによる像露光とによって像形成体１０上に形成された静電潜像を、現像スリーブ１３０への現像バイアス電圧の印加により現像スリーブ１３０の搬送する現像剤層が非接触の条件で、反転現像する。
【００４５】
次に上述のカラー画像形成装置の画像形成プロセスを説明する。
【００４６】
本装置とは別体の画像読み取り装置で原稿画像を撮像素子により読み取った画像情報あるいはコンピュータで編集された画像情報がＹ，Ｍ，ＣおよびＫの色別の画像信号として一旦メモリに記憶され格納される。
【００４７】
画像記録のスタートにより感光体駆動モータが始動して駆動歯車６２が回転され像形成体１０を前述のように回転させる。同時に帯電器１１Ｙの帯電作用が開始されて像形成体１０の周壁に一様に電位を付与する。その電位を付与された周壁内面に像露光手段１２Ｙが前述のメモリからの第１色例えばＹの画像信号によって変調された像露光を入射して周壁表面に原稿画像のＹ成分画像に対応する静電潜像を形成する。その静電潜像が現像器１３Ｙにより現像スリーブ１３０上の現像剤層を非接触にした条件で反転現像され、像形成体１０の表面にＹトナー像が形成される。
【００４８】
次いで像形成体１０はＹトナー像を保持する周壁表面に帯電器１１Ｍによる帯電作用を受けて一様に電位を付与され、その電位を付与された周壁内面に像露光手段１２Ｍの第２色例えばＭの画像信号に基づく像露光を入射される。それによって周壁表面に形成された静電潜像が現像器１３Ｍによる非接触の反転現像によりＭトナー像に現像されることで、像形成体１０の表面にＹトナー像とＭトナー像の重ね合わせから成る２色像が形成される。
【００４９】
２色像を保持する像形成体１０の周壁は同様にそれぞれ帯電器１１Ｃ、像露光手段１２Ｃ及び現像器１３Ｃによる帯電作用、像露光入射及び現像を受けて表面にＣトナー像を形成されることでＹ，Ｍ，Ｃの３トナー像の重ね合わせから成る３色像を形成される。また必要に応じてさらに３色像を保持する像形成体１０の周壁は同様にそれぞれ帯電器１１Ｋ、像露光手段１２Ｋ及び現像器１３Ｋによる帯電作用、像露光入射及び現像を受けて表面にＫトナー像を形成されることでＹ，Ｍ，Ｃ，Ｋの４トナー像の重ね合わせから成る４色像を形成される。すなわち、３色または４色カラー画像が像形成体１０の一回転内でその周面上に形成される。
【００５０】
以上のように本発明のカラー画像形成装置では、像露光手段１２Ｙ〜１２Ｋが像形成体１０の内部から透明基体を通して有機感光層に像露光を入射するから、第１色の像露光だけでなく、第２，第３および第４の色に対応した像露光も先に形成されたトナー像の影響を受けることなく入射されて、同様の鮮明なトナー像を与える静電潜像を形成する。そして現像器１３Ｙ〜１３Ｋによる現像に際しては、それぞれ現像スリーブ１３０に直流またはさらに交流を加えた現像バイアスが印加され、それによって現像スリーブ１３０上の一成分或いは二成分現像剤層からトナーが透明電導層を接地された像形成体１０に飛翔して付着し、先に形成されたトナー像に影響を与えることのない非接触反転現像が行われる。
【００５１】
かくして像形成体１０の周面上に形成された３色または４色のカラー画像は像形成体１０を小径化するために用いた中間転写体１４の周面に転写される。この中間転写体１４は、電気抵抗１０⁸〜１０¹¹Ω・ｃｍ、厚さ１００〜５００μｍのウレタンゴム層上に同様な抵抗値を有するテフロン層を分離用表層として設けたベルトから成り、ローラ１４Ａ，１４Ｂ，１４Ｃ及び１４Ｄによって張架されて、ローラ１４Ａとローラ１４Ｂの間を像形成体１０の周面に接触させてカラー画像の被転写域とし、ローラ１４Ｃと対向する転写ローラ１５との間を転写紙等の転写材にカラー画像を転写させる転写域として、ローラ１４Ｄに伝達される動力により像形成体１０の周速度に同期して図１の反時計方向に回動する。
【００５２】
像形成体１０の外周面に付着したカラー画像は、接地したローラ１４Ａにより像形成体１０の外周面と接触するように案内されて、トナーの帯電と逆極性の１乃至２ｋＶのバイアス電圧を印加されたローラ１４Ｂにより像形成体１０の外周面から離れるように案内される被転写域の中間転写体１４に、トナーを飛散させることなく効率良く転写され、中間転写体１４により転写域へと運ばれる。
【００５３】
一方、不図示の給紙カセットの給紙ローラ１７の作用により転写紙Ｐが搬出されてタイミングローラ１８に給送され、中間転写体１４上のカラー画像の搬送に同期して転写ローラ１５による転写域へと給紙される。
【００５４】
転写ローラ１５は、中間転写体１４の周速度に同期して反時計方向に回動し、給紙された転写紙Ｐを接地状態にあるローラ１４Ｃとの間で中間転写体１４に圧接させると共に、トナーの帯電と逆極性の１乃至２ｋＶのバイアス電圧を印加されて、中間転写体１４上のカラー画像を転写紙Ｐ上に転写させる。
【００５５】
カラー画像を転写された転写紙Ｐは、除電され、搬送板１９を介し定着装置２１に搬送され、熱ローラ２１Ａと加圧ローラ２１Ｂの間で加熱圧縮を受けてトナーを定着された後、排紙ローラ２２を介して装置外に排出される。
【００５６】
なお、カラー画像転写後の像形成体１０、中間転写体１４並びに転写ローラ１５の表面にはそれぞれのクリーニング装置１００、クリーニング装置１４０並びにクリーニング装置１５０のクリーニングブレードが常時圧接して残留トナー等の付着汚れの除去を行うから、いずれの表面も常に清浄な状態に維持される。クリーニング装置１００とクリーニング装置１４０の回収したトナーは不図示の搬送スクリュー内蔵のトナー搬送管によって廃トナー収納容器に収容される。
【００５７】
【発明の効果】
以上詳述したように、本発明の請求項１乃至２３の構成の複数の像露光手段を像形成体内部に収容したカラー画像形成装置においては、像露光手段を取り付けた光学系支持手段に像形成体が回転自在に支持されて一体化されているから、像形成体の内周面と複数の像露光手段の関係位置精度が安定して正確に保たれて、像形成体を円滑に回転することができ、したがって色ずれのない鮮明なカラー画像を容易に形成できて、一体化した光学系支持手段の組立、分解、保守及び装置本体に対する取り付け、取り外しが容易に行えると言う効果を奏する。
【００５８】
さらに請求項５乃至１１の構成の装置においては、光学系支持手段の像形成体軸受支持部に肉抜き孔または溝を設けて、それを像露光手段の電気配線や像形成体等の空冷に利用するようにしているから、一体化した光学系支持手段が軽量化されて、一層安定して鮮明なカラー画像の形成ができるし、一体化した光学系支持手段の組立、分解も一層容易に行えるようになると言う効果も奏する。また請求項１２乃至１８の構成の装置においては、光学系支持手段を中空にしたことで、同様の軽量化や安定したカラー画像形成および組立、分解の一層容易性が得られるようにしている。また請求項１９およびそれに付帯した請求項２１乃至２３の構成の装置においては、光学系支持手段の露光手段固定部が像露光手段両端部を固定する固定部分の間を空腔に形成していることによって、一体化した光学系支持手段を軽量化すると言う効果も奏する。
【図面の簡単な説明】
【図１】本発明に係るカラー画像形成装置の例を示す概要構成断面図である。
【図２】本発明に係るカラー画像形成装置の像形成体を一体化した光学系支持手段の取り付け状態を示す部分正面図である。
【図３】請求項１乃至１１及び請求項２０乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図である。
【図４】請求項１２乃至１８の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図である。
【図５】請求項１９及び請求項２１乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図である。
【図６】請求項２０乃至２３の例に係る像形成体を一体化した光学系支持手段の取り付け状態を示す軸方向部分断面図である。
【符号の説明】
１０像形成体
１０Ａ端部環
１０Ｂ端部歯車環
１０Ｃ軸受
１０Ｇドラム歯車
１１Ｙ〜１１Ｋ帯電器
１２Ｙ〜１２Ｋ像露光手段
１３Ｙ〜１３Ｋ現像器
１３０現像スリーブ
１３３〜１３６スリーブ歯車
３０空腔
３１ユニット軸
３１Ｈ中空孔
３２，３３ブラケット
３２０，３３０露光手段固定部
３２１，３３１像形成体軸受支持部
３５コの字状ブラケット
３５Ｂ連結梁部
３６位相ピン
３８前面板
７０Ａ手前側板
７０Ｂ奥側板
７１，７３，７４案内支持レール
７２軸受座[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a color image forming apparatus such as an electrophotographic color copying machine or a recording apparatus, and in particular, an optical system support means having a plurality of image exposure means attached thereto, and a drum-like shape containing the image exposure means therein. And a plurality of developing units disposed around the image forming body.
[0002]
[Prior art]
Since the color image forming apparatus as described above accommodates a plurality of image exposure means inside the image forming body, it is possible to use an image forming body having a small diameter with a relatively short peripheral surface length, and reducing the size of the apparatus. Since the image exposure is incident on the inner peripheral surface of the image forming body to which toner does not adhere, the second and subsequent electrostatic images can be formed with the same sharpness as the first color electrostatic image, It has the feature that a color image with good color balance can be formed. However, since the conventional structure has a compact structure, it takes time to assemble, disassemble, and maintain, and the image forming body and the support for the internal image exposure means are completely separated. There is a problem that it is difficult to rotate the image forming body smoothly by keeping the distance between the forming body peripheral surface and the plurality of image exposing means constant, and color shift tends to occur in the formed color image.
[0003]
[Problems to be solved by the invention]
The present invention has been made to solve the above-described problems of the color image forming apparatus. In a color image forming apparatus in which a plurality of image exposure means are accommodated in an image forming body, an image forming body peripheral surface and a plurality of image forming bodies are provided. The first object of the present invention is to provide an apparatus in which the distance of the image exposure means is kept constant, the image forming body can be rotated smoothly, and therefore a clear color image without color misregistration can be easily formed. The second object is to provide an apparatus that can be easily disassembled and maintained, and the third object is to provide an apparatus in which the integration of an image forming body and a plurality of image exposure means is reduced in weight. .
[0004]
[Means for Solving the Problems]
The present invention relates to an optical system support means having a plurality of image exposure means attached thereto, a drum-like image forming body containing the image exposure means therein, and the image forming body of A color image forming apparatus comprising a plurality of developing units disposed around the optical system supporting unit according to claim 1. The pair of brackets fixed to the shaft are configured such that the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the image forming body bearing support portions which are not facing each other are separated from each other. The formed body is rotatably supported, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, The image forming body bearing support portion rotatably supports the image forming body having a passive gear on the outer periphery on one end side, and the image forming body bearing support portion Axial direction Protruding outward The axis The first and second objects are achieved by a configuration in which the apparatus main body side plate is held and attached to the apparatus main body.
[0005]
That is, in the apparatus according to the first aspect, the optical system support means to which the plurality of image exposure means are attached rotatably supports the image forming body by the image forming body bearing support portion. Thus, the first object can be achieved, in which the distance between the image forming member and the image forming member is kept constant, and the image forming member can be rotated smoothly. Further, since the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, it is possible to easily assemble and disassemble the optical system supporting means and the image forming body in which a plurality of image exposure means are fixed. By having a passive gear on the outer periphery on one end side, the passive gear is engaged with and disengaged from the drive gear on the apparatus main body side when the optical system supporting means integrated with the image forming body is engaged with and disengaged from the apparatus main body side plate. The second object which can be easily assembled and disassembled is achieved.
[0006]
The shaft of the optical system support means held on the apparatus main body side plate of claim 2 in the apparatus of claim 1 of 2. A structure in which an optical system supporting means integrated with an image forming body is supported on an apparatus main body side plate can be made compact by adding a configuration characterized in that the outer diameter is in a range of 10 to 30 mm. The shaft of the optical system support means held on the apparatus main body side plate of claim 3 in the apparatus of claim 2 But Than the image forming body bearing support Axial direction Protruding outward Partial By adding a configuration characterized in that the length is in the range of 20 to 100 mm, it is possible to easily and reliably support the optical system supporting means integrated with the image forming body on the apparatus main body side plate. The electric wiring to the image exposure means according to claim 4 is connected to the passive gear. To position By adding a configuration characterized in that it is performed from the side opposite to the side, wiring processing of the image exposure means becomes particularly easy, and rotation transmission to the image forming body is transmitted to the apparatus main body side plate on the passive gear side of the image forming body. It becomes easy to provide the means, and the assembly / disassembly of the optical system support means with respect to the apparatus main body side plate can be performed particularly easily.
[0007]
The present invention also provides an optical system supporting unit having a plurality of image exposing units, a drum-shaped image forming unit containing the image exposing unit therein, and the image forming unit. of 6. A color image forming apparatus comprising a plurality of developing units disposed around the optical system supporting unit according to claim 5. The pair of brackets fixed to the shaft are configured such that the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the image forming body bearing support portions which are not facing each other are separated from each other. The formed body is rotatably supported, and the diameter of the image forming body bearing support portion is the diameter of the exposure means fixing portion. An image forming body bearing support portion having a larger hole or groove, and the image forming body bearing support portion rotatably supports the image forming body having a passive gear on an outer periphery on one end side. From formed body bearing support Axial direction Protruding outward The axis The first to third objects are achieved by a configuration in which the apparatus main body side plate is held and attached to the apparatus main body.
[0008]
That is, the apparatus according to claim 5 achieves the third object of reducing the weight of the optical system support means in which the image forming body is integrated by providing a lightening hole or groove in the image forming body bearing support portion of the optical system support means. Otherwise, the first and second objects are achieved in the same manner as the device of claim 1.
[0009]
Further, an optical system in which the image forming body is integrated by adding the configuration of the apparatus according to claim 5 wherein the outer diameter of the image forming body bearing support portion is in the range of 30 to 100 mm. It is possible to limit the enlargement of the support means and provide a lightening hole or groove in the image forming body bearing support portion to reduce the weight or to pass the cooling air of the electrical wiring of the image exposure means or the image forming body. And facilitates the achievement of the object of claim 5.
[0010]
The apparatus according to claim 5 or 6 is characterized in that the electrical wiring of the image exposure means is passed through the lightening hole or groove of the image forming body bearing support portion according to claim 7, and The electric wiring of the image exposure means according to claim 8 is a passive gear of the image forming body. Is located What is the side Axially By adding a configuration characterized by being connected to the power supply on the opposite side, the wiring processing of the image exposure means in the integration of the image forming body and the optical system supporting means becomes easier, and further the image forming body is integrated. Since the optical system support means can be easily engaged and disengaged from the apparatus main body side plate, the second object can be further achieved.
[0011]
Further, the apparatus according to claims 5 to 8 is characterized in that an air flow is passed through a hollow hole or groove of the image forming body bearing support portion according to claim 9, and the air flow according to claim 10 is Passive gear of the image forming body Is located What is the side Axially From the opposite side, the optical system support means Said 12. A structure characterized by flowing into a lightening hole or groove of an image forming body bearing support portion, and further comprising a cooling fin provided in the lightening hole or groove of the image forming body bearing support portion according to claim 11. By adding the characteristic features, it is possible to prevent the temperature rise of the image forming body having the image exposure means inside by air flow, so that the rotation, charging, electrostatic image and toner image formation of the image forming body can be performed stably. This facilitates the achievement of the first object that a clear color image without color misregistration can be formed.
[0012]
The present invention also provides an optical system supporting unit having a plurality of image exposing units, a drum-shaped image forming unit containing the image exposing unit therein, and the image forming unit. of 13. A color image forming apparatus comprising a plurality of developing units arranged around the optical system supporting unit according to claim 12. The pair of brackets fixed to the shaft are configured such that the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the image forming body bearing support portions which are not facing each other are separated from each other. The forming body is rotatably supported, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, and the shaft of the optical system support means Is hollow The The image forming body bearing support portion rotatably supports the image forming body having a passive gear on the outer periphery on one end side, Said From the image forming element bearing support Axial direction Hollow projecting outward Axis The first to third objects are achieved by a configuration in which the apparatus main body side plate is held and attached to the apparatus main body.
[0013]
That is, the apparatus of claim 12 is the same as the apparatus of claim 1 except that the third object of reducing the weight of the optical system support means in which the optical system support means is hollow and the image forming body is integrated is achieved. The first and second objects are achieved in the same way as the apparatus of claim 1.
[0014]
Further, in the apparatus of claim 12, the hollow of the optical system supporting means supported by the apparatus main body side plate of claim 13 is provided. Axial By adding a configuration characterized in that the outer diameter is in the range of 30 to 80 mm, the strength of the hollow shaft portion is sufficiently maintained, and the hollow hole can be easily used in addition to weight reduction. Further, in the apparatus of claims 12 to 13, the optical system support means of claim 14 is hollow. Axial 16. The structure according to claim 15, wherein the electrical wiring of the image exposure means is passed through a hollow hole, and the electrical wiring of the image exposure means is a passive gear of the image forming body. The side where Is added to the power source on the opposite side to facilitate the wiring process of the image exposure means, and the image forming body is connected to the apparatus main body side plate on the passive gear side of the image forming body. It becomes easy to provide the rotation transmission means, and this facilitates the achievement of the second object in which the assembly and disassembly of the optical system support means with respect to the apparatus main body side plate is easily performed.
[0015]
Further, in the apparatus of claims 12 to 15, the hollow of the optical system support means of claim 16 is provided. Axial 18. A configuration characterized in that an air flow is passed through a hollow hole, and further wherein the air flow is the passive gear of the image forming body. Is located Hollow of the optical system support means from the side opposite to the side Axial The image exposure is performed by adding the configuration characterized by flowing into the hollow hole, and further the configuration characterized in that a cooling fin is provided in the hollow hole of the hollow shaft portion of the optical system support means. Since the temperature rise of the image forming body having the means can be prevented by the air flow, rotation of the image forming body, charging, electrostatic image formation and toner image formation can be performed stably, and there is no color misregistration. This facilitates the achievement of the first object that a simple color image can be formed.
[0016]
The present invention also includes an optical system support unit having a plurality of image exposure units attached thereto, a drum-shaped image forming body containing the image exposure unit therein, and a plurality of developing devices disposed around the image forming unit. In the color image forming apparatus, the optical system support unit according to claim 19, wherein the exposure unit fixing unit to which the image exposure unit is attached forms a cavity between the fixed portions that fix both ends of the image exposure unit. The connection portion of the electrical wiring of the image exposure means faces the cavity, and from the exposure means fixing portion Axial direction An image forming body bearing support portion is provided on the outer side, and the image forming body is rotatably supported by the image forming body bearing support portion. Axial direction Protruding outward The axis The first to third objects are achieved by a configuration in which the apparatus main body side plate is held and attached to the apparatus main body.
[0017]
That is, the apparatus of the nineteenth aspect is similar to the apparatuses of the first, fifth and twelfth aspects, in that the optical system supporting means supporting the plurality of image exposing means is integrated with the image forming body and supported by the apparatus main body side plate. Therefore, the distance between the inner peripheral surface of the image forming body and the plurality of image exposure means is kept constant, and the first object that the clear color image without color misregistration can be easily formed and the optical integrated with the image forming body The second object of easy assembly, disassembly, maintenance and the like of the system support means with respect to the apparatus main body is achieved, and a cavity is formed between the fixed portions where the optical system support means fixes both ends of the plurality of image exposure means. By forming, the third object of reducing the weight of the optical system supporting means integrated with the image forming body is achieved. Further, since the connection portion of the wiring of the image exposure means faces the cavity formed in the optical system support means, the wiring of the image exposure means can be easily performed, and the optical system support means integrated with the image forming body The second object of facilitating assembly, disassembly, maintenance, etc. is also achieved.
[0018]
The present invention also provides an optical system supporting unit having a plurality of image exposing units, a drum-shaped image forming unit containing the image exposing unit therein, and the image forming unit. of 21. A color image forming apparatus comprising a plurality of developing units arranged around the optical system supporting unit according to claim 20. The pair of brackets fixed to the shaft are configured such that the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the image forming body bearing support portions which are not facing each other are separated from each other. The formed body is rotatably supported, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, Fixing the image exposure means in which the connection part of the electrical wiring is located on the end face or side face; Said From the image forming element bearing support Axial direction Protruding outward The axis The first and second objects are achieved by a configuration in which the apparatus main body side plate is held and attached to the apparatus main body.
[0019]
That is, the apparatus of the twentieth aspect has the same configuration as the apparatus of the first, fifth, twelfth, and nineteenth aspects, in which the optical system support means supporting a plurality of image exposure means is integrated with the image forming body and supported by the apparatus main body side plate. Therefore, the first and second objects are similarly achieved, and the optical system support means is fixed in a state where the image exposure means in which the connecting portion of the electric wiring is positioned on the end face or the side face is placed on the outer peripheral face. Therefore, the second object of facilitating the assembly, disassembly, maintenance and the like of the optical system support means integrated with the image forming body can be easily performed by wiring the image exposure means.
[0020]
Further, the apparatus according to claim 19 and claim 20 is added with the structure according to claim 21, wherein the image forming body supported by the image forming body bearing support portion has a passive gear on an outer periphery on one end side. Accordingly, since the engagement of the driving means provided on the apparatus main body side and the passive gear of the image forming body is facilitated, the optical system support means integrated with the image forming body is easily engaged with and disengaged from the apparatus main body side plate. The second objective is also achieved.
[0021]
Further, in the apparatus of claim 21, the electrical wiring of the image exposure means of claim 22 passes through the inside of the bearing supported by the image forming body bearing support portion of the optical system support means and the connection portion of the image exposure means. 24. The structure of claim 23, further comprising: a power supply for electrical wiring of the image exposure means according to claim 23, wherein the power supply of the image forming member is a passive gear. Is located What is the side Axial direction By adding a configuration characterized by being on the opposite side, the wiring processing of the image exposure means in the integration of the image forming body and the optical system supporting means becomes easy, and further, the optical system support in which the image forming body is integrated Since the engagement and disengagement of the means with respect to the apparatus main body side plate is facilitated, the achievement of the second object is further promoted.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0023]
FIG. 1 is a schematic sectional view showing an example of a color image forming apparatus according to the present invention, FIG. 2 is a partial front view showing a mounting state of an optical system support means integrated with an image forming body, and FIG. 11 and FIG. 4 is a partial sectional view in the axial direction showing an attached state of the optical system support means in which the image forming bodies according to the examples of claims 11 and 20 to 23 are integrated. FIG. FIG. 5 is an axial view showing the mounting state of the optical system supporting means integrated with the image forming body according to the examples of claims 19 and 21 to 23. FIG. 6 is a partial axial sectional view showing an attached state of the optical system support means in which the image forming bodies according to the examples of claims 20 to 23 are integrated.
[0024]
In the figure, reference numeral 10 denotes a drum-shaped image forming body. The image forming body 10 has a transparent conductive layer and an organic photoreceptor layer (OPC) on the outer periphery of a cylindrical substrate made of a transparent member such as optical glass or transparent acrylic resin. A photosensitive drum portion is formed by coating or the like, and has an end ring 10A in which a bearing 10C is fitted on the inner circumference and a drum gear 10G which is a passive gear on the outer circumference at inner diameters at both ends of the photosensitive drum portion. The end gear ring 10B is integrally fitted. Here, the drum gear 10G is not limited to the external gear, and may be an internal tooth. Even if the end ring 10A or the end gear ring 10B is fitted to the outer diameter of the photosensitive drum portion, Of course, it may be integrally formed.
[0025]
11Y to 11K are chargers using a scorotron corona discharger, and 12Y to 12K are composed of LEDs arranged in parallel to the axial direction of the image forming body 10 and an imaging element (trade name: Selfoc lens). Line-shaped image exposure means. The image exposure means 12Y to 12K sequentially receive color-specific image signals such as separated colors read by a separate image reader, for example, from the memory and input them as electrical signals.
[0026]
The image forming body 10 and the image exposing means 12Y to 12K are integrally incorporated as a unit. In other words, the unit shaft 31 and a pair of front and rear brackets 32 and 33 fitted and fixed to the outer diameter of the unit shaft 31 constitute an optical system support means, and the image exposure means 12Y has an outer diameter at a portion close to each other of the brackets 32 and 33. .About.12K are fixed, and the image forming body 10 is rotatably supported on the outer diameters of the portions of the brackets 32 and 33 separated from each other. Accordingly, the portions of the brackets 32 and 33 that are close to each other are the exposure means fixing portions 320 and 330, and the portions of the brackets 32 and 33 that are separated from each other are the image forming body bearing support portions 321 and 331.
[0027]
The image forming body 10 is freely rotatable when the bearings 10C fitted to the end ring 10A and the end gear ring 10B at both ends are fitted to the image forming body bearing support portions 321 and 331 of the brackets 32 and 33, respectively. Supported by Prior to that, the image exposure means 12Y to 12K are adjusted at both ends via the sticking member 34 so that the distance between the image forming body 10 and the inner surface of the photosensitive drum portion is in a predetermined positional relationship. , 33 are fixed to the exposure means fixing portions 320, 330 by adhesion.
[0028]
As described above, the optical system support means integrated with the image forming body described in claims 1, 5, 12, 19, 20, etc. is configured, and thereby the relative positions of the image exposure means 12 Y to 12 K with respect to the image forming body 10 are accurately determined. Since it can be set well, it is easy to accurately align the positions of the electrostatic latent images formed on the image forming body 10 by the image exposure means 12Y to 12K, and a color image without color misregistration can be easily formed.
[0029]
In the example of FIGS. 3 to 6, the cavity 30 according to claim 19 is formed between the exposure means fixing portions 320 and 330 fixing both ends of the image exposure means 12Y to 12K, thereby the unit. Further, in the example of FIG. 5, connection of the electrical wiring 121 is facilitated by providing the connection portion 122 of the electrical wiring 121 for driving the image exposure means 12 </ b> Y to 12 </ b> K on the cavity 30 side. . On the other hand, if the weight reduction by the cavity 30 is not considered as in the configuration of the first, fifth, twelfth and twentieth aspects, the image exposure means 12Y is formed on the outer surface of the bracket in which the brackets 32 and 33 are integrally connected. 21 to 12K, and the image exposure means 12Y to 12K as shown in FIGS. 3 and 6 have the connection portion 122 of the electric wiring 121 disposed on the end surface or the side surface. The means 12Y to 12K can be easily connected to the electric wiring 121.
[0030]
The unit shaft 31 is positioned between the side plate portions 35A of the U-shaped bracket 35 in which the brackets 32 and 33 holding the image forming body 10 and the image exposure means 12Y to 12K are composed of both side plate portions 35A and connecting beam portions 35B. Then, it is rotatably mounted on both side plate portions 35A so that both end portions protrude from both side plate portions 35A. A phase pin 36 is planted at the end of the unit shaft 31 protruding outside the one side plate portion 35A of the U-shaped bracket 35, and the end protruding outside the other side plate portion 35A is screwed later. The front plate 38 is fastened and fixed by the mating tip nut 37.
[0031]
In the example of FIGS. 2 to 6, the U-shaped bracket 35 is attached to form a unit as described above, and the U-shaped bracket 35 mounts the unit in the apparatus main body as will be described later. In addition, the image forming body 10 and the image exposing means 12Y to 12K are not brought into contact with the floor surface by setting the connecting beam portion 35B to the bottom surface when placing the unit on the floor surface. It is also used as a stand.
[0032]
3, 5, and 6, the unit shaft 31 is a solid shaft, and the image forming body 10 is rotatably supported by the image forming body bearing support portions 321 and 331 of the brackets 32 and 33 fixed to the unit shaft 31. FIGS. 3 and 6 show the arrangements of the image exposure means 12Y to 12K in the arrangement of the twentieth aspect, respectively, and are arranged on the end surface and the side surface, respectively. An example is shown. FIG. 5 shows the structure of claim 19 as described above. 5 and FIG. 6, the electric wiring 121 connected to the connection part 122 of the image exposure means 12Y to 12K is connected to the exposure means fixing parts 320 and 330 of the brackets 32 and 33. ˜12K and the image forming body bearing support portion 321 of the bracket 32 is taken out of the image forming body 10 through a lightening hole or groove (hereinafter simply referred to as a lightening hole) 32A. Further, the connection terminal at the tip is connected to the power source through the notch portion 35C of the side plate portion 35A of the U-shaped bracket 35 and the appropriately provided groove or hole of the front plate 38. Yes. On the other hand, in the example of FIG. 3, since the connection part 122 of the image exposure means 12Y to 12K is on the end face, the wiring is similarly taken out of the unit even if there is no gap between the arrangement of the image exposure means 12Y to 12K. Can be connected to the power supply. In either example, the wiring process is easy and the unit can be easily attached and detached.
[0033]
In the example of FIG. 4, the unit shaft 31 is formed as a hollow shaft as in the structure of claim 12 to reduce the weight of the unit. The electrical wiring 121 of the image exposure means 12Y to 12K is a hollow hole through a hole 31A provided on the tube wall of the unit shaft 31 from a connection portion 122 provided on the back surface facing the unit shaft 31 side of the image exposure means 12Y to 12K. 31H enters the hollow hole 31H through the hole 31B provided in the tube wall of the unit shaft 31 on the front plate 38 side of the bracket 32, and the notch 35C of the side plate portion 35A of the U-shaped bracket 35 and the front plate The connection terminals at the tip are connected to the power source through 38 appropriately provided grooves or holes. This facilitates connection / disconnection of the wiring when attaching / detaching the unit to / from the apparatus main body, so that the attachment / detachment of the unit is also facilitated.
[0034]
The outer diameter of both end portions protruding from the U-shaped bracket 35 of the hollow unit shaft 31 is in the range of 30 to 80 mm in the configuration of claim 13, and the electric wiring 121 can be easily passed while maintaining sufficient strength. This is preferable because a hollow hole can be provided and the image forming apparatus does not have to be enlarged. Further, it is possible to adopt the configuration of claim 16 in which an air flow is caused to flow through the hollow hole 31H of the unit shaft 31 so as to prevent the temperature inside the image forming body 10 from rising due to the driving of the image exposure means 12Y to 12K. The structure of claim 17 that flows from the front plate 38 is preferable because the casting duct can be connected regardless of the driving means such as the image forming body 10 and the developing roller of the developing device. In order to further increase the cooling efficiency, the configuration of claim 18 is also preferable in which cooling fins are provided in the hollow hole 31H or the outer diameter of the unit shaft 31 or the like. By providing such a cooling unit, stable image formation can be performed.
[0035]
3 to 6, the connection terminals of the electrical wiring 121 are connected to the power supply after the unit is mounted on the apparatus main body. However, when the connection portion of the power supply is inside the front plate 38, the front plate This is performed at the stage where the unit prior to mounting 38 is inserted into the apparatus main body. In that case, there is no need for a groove or hole for passing the wiring through the front plate 38. Contrary to the illustrated example, the wiring can be extended to the planting side of the phase pin 36 and connected to the connection terminal of the power source provided on the back side plate 70B side of the unit body in the unit insertion direction. The connection terminal of the unit needs to be fixedly provided on the unit shaft 31 so that the connection is performed upon completion of the insertion of the unit. That is, the illustrated example of the configuration of claims 4, 8, 15, and 23 in which the electric wiring 121 extends to the opposite side of the drum gear 10G side of the image forming body 10 and is connected to the power source is more preferable.
[0036]
3, 5, and 6, the diameters of the image forming body bearing support portions 321 and 331 that support the bearing 10 </ b> C of the image forming body 10 of the brackets 32 and 33 of the optical system supporting means are the image exposure means 12 </ b> Y. The structure according to claim 1, which is larger than the diameter of the exposure means fixing portions 320, 330 for fixing ~ 12K, and further, according to the structure according to claim 5, wherein the image forming body bearing support portions 321, 331 are provided with hollow holes 32A, 33A. It is easy to integrate the image forming body 10 into the optical system supporting means to which the image exposing means 12Y to 12K are attached, and the image forming body bearing support portions 321 and 331 are provided with claims 4, 7, It is easy to provide the lightening holes 32A and 33A serving as the passage of the electric wiring 121 having the configuration of 8, 22, and 23, and further, the lightening holes 32A and 33A can be easily used as the cooling air passage according to the ninth and tenth aspects. So preferable
[0037]
In the configuration of the fifth aspect, the outer diameter of the flange portion is 30 to 100 mm of the configuration of the sixth aspect, wherein the image forming body bearing support portions 321 and 331 of the brackets 32 and 33 are provided with the hollow holes 32A and 33A. However, the lightening holes 32A and 33A can be used for passing the electrical wiring 121 of the image exposure means 12Y to 12K as in the configuration of claims 7 and 8, in addition to the purpose of reducing the weight. It is preferable because it can be used to pass an air flow as in the configuration and the apparatus does not need to be enlarged. The drum gear of the image forming body 10 also cools the inner peripheral surface of the image forming body 10 and the image exposure means 12Y to 12K through the air holes 32A and 33A of the image forming body bearing support portions 321 and 331. The structure of claim 10 in which air flows into the lightening hole 32A of the image forming body bearing support portion 321 from the side opposite to the 10G side, that is, the front plate 38 side, is configured to generate heat like the image forming body driving means on the inflow side. Since there is no source etc., it is preferable.
[0038]
In the case where an air flow is passed through the lightening holes 32A and 33A, it is preferable in terms of cooling efficiency that the cooling fins are provided in the lightening holes 32A and 33A. Further, when these open holes 32A and 33A are released, the scattered toner enters the inside of the image forming body 10 and contaminates the inner peripheral surface and the light emitting surfaces of the image exposure means 12Y to 12K. It is preferable to prevent the toner and the like from entering by blocking.
[0039]
On the other hand, in the form of claim 1 that does not require a hollow hole, the outer diameter of the portion of the unit shaft 31 that protrudes from the U-shaped bracket 35 and is supported by the apparatus main body side plates 70A and 70B is the outer diameter. The structure of 10 to 30 mm of the configuration is preferable because the fixing structure to be described later of the unit is compact and sufficient strength can be achieved, and the length protruding from the U-shaped bracket 35 is 20 to 100 mm of the configuration of claim 3. It is preferable that stable fixation can be achieved and the apparatus does not need to be enlarged.
[0040]
2 to 6, the unit is attached to the apparatus main body as follows. That is, the unit has the connecting beam portion 35B of the U-shaped bracket 35 from the insertion hole 70A1 provided in the front side plate 70A of the apparatus main body, with the phase pin 36 side of the unit shaft 31 as the head, at the front and back of the apparatus main body. The drum gear 10G of the image forming body 10 is engaged with a guide support rail 71 provided between both side plates 70A and 70B and sent into the apparatus main body, and is decelerated from a motor (not shown) installed on the back side plate 70B side. While engaging with the drive gear 62, the phase pin 36 is engaged with a positioning taper groove formed in the bearing seat 72 provided on the back plate 70B of the apparatus main body, and in this state, the front plate 38 is screwed to the front of the apparatus main body. It is fixedly attached to the side plate 70A. As a result, the image forming body 10 and the image exposing means 12Y to 12K are installed in the apparatus main body at an accurate position and phase.
[0041]
In the example of FIG. 2, in order to fix the front plate 38 to the front side plate 70A of the apparatus main body, the front side plate 70A is engaged with a plurality of reference holes H1 provided in the front plate 38 to engage the front side plate 70A. 38, when the front plate 38 is first fixed to the front plate 70A of the apparatus main body, the front plate 38 is fastened and fixed by the unit shaft 31 and the tip nut 37 so as not to rotate. Is performed after the reference hole H1 and the reference pin P2 are engaged. The front plate 38 is provided with insertion ports 38A for the chargers 11Y to 11K.
[0042]
The chargers 11Y to 11K are inserted into the apparatus main body through the insertion port 38A of the front plate 38 attached to the front side plate 70A with the power receiving terminal side at the head, and are guided and supported between the front and back side plates 70A and 70B. After the power receiving terminal is fed by the guide of the rail 73 so as to be connected to the power supply terminal provided on the back side plate 70B, the push lid 39 is screwed to the insertion port 38A, so that a predetermined interval position is set with respect to the image forming body 10. Installed to keep and operate. Therefore, the unit is removed from the apparatus main body after the chargers 11Y to 11K are first taken out from the insertion port 38A and then the front plate 38 is detached from the front side plate 70A and pulled out. In addition, prior to the removal of the unit, the pressing action of the developing units 13Y to 13K, the intermediate transfer belt 14 and the cleaning blade of the cleaning device 100, which will be described later, with respect to the peripheral surface of the image forming body 10 is released by a conventionally known means or the like. Needless to say, it is necessary to evacuate about 1 mm or more.
[0043]
The developing units 13Y to 13K are each developed with a developer using yellow (Y), magenta (M), cyan (C), and black (K) toners, and are inserted into the apparatus main body from the front side plate 70A side. In the example shown in FIGS. 3 to 6, the eccentric groove is moved by the contact / separation operation handle 40 according to the guide support rail 74 provided between the front and rear side plates 70A and 70B. The cam 41 is rotated to displace the contact / separation action shaft 42 engaged with the eccentric groove cam 41 supported on the lower surface side of the guide support rail 74 in the axial direction, and thereby the developing device 13Y with a spring provided on the shaft. The rotary spacer rollers on both sides of the developing sleeves 130 are pushed so as to come into pressure contact with the image forming body 10 to be installed in the apparatus main body. As a result, the reduction gears 53 to 56 from a motor (not shown) installed on the back plate 70B side mesh with the sleeve gears 133 to 136 integral with the developing sleeve 130. With the reverse operation described above, the pressure contact of the developing units 13Y to 13K with respect to the image forming body 10 is released and the apparatus is removed from the apparatus main body.
[0044]
As shown in FIG. 1, the installed developing devices 13Y to 13K occupy positions that are substantially symmetrical to the left and right of the vertical line passing through the rotation center of the image forming body 10 and separated from the upper and lower sides of the horizontal line passing through the rotation center. The developing sleeve 130 which is a layer conveying roller rotates in the same surface movement direction while maintaining a predetermined gap with the image forming body 10, and forms an image by charging by the chargers 11Y to 11K and image exposure by the image exposure means 12Y to 12K, respectively. The electrostatic latent image formed on the body 10 is reversely developed under the condition that the developer layer conveyed by the developing sleeve 130 is not in contact with the developing sleeve 130 by applying a developing bias voltage to the developing sleeve 130.
[0045]
Next, an image forming process of the above color image forming apparatus will be described.
[0046]
Image information obtained by reading an original image with an image sensor with an image reading device separate from this device or image information edited by a computer is temporarily stored in a memory as image signals for Y, M, C, and K colors. Is done.
[0047]
When the image recording is started, the photosensitive member driving motor is started and the driving gear 62 is rotated to rotate the image forming body 10 as described above. At the same time, the charging action of the charger 11Y is started and a potential is uniformly applied to the peripheral wall of the image forming body 10. The image exposure means 12Y receives image exposure modulated by an image signal of the first color such as Y from the above-mentioned memory on the inner surface of the peripheral wall to which the potential is applied, and the static image corresponding to the Y component image of the original image is input to the peripheral wall surface. An electrostatic latent image is formed. The electrostatic latent image is reversely developed by the developing device 13Y under the condition that the developer layer on the developing sleeve 130 is not contacted, and a Y toner image is formed on the surface of the image forming body 10.
[0048]
Next, the image forming body 10 is charged uniformly by the charging operation by the charger 11M on the peripheral wall surface holding the Y toner image, and the second color of the image exposure means 12M, for example, is applied to the inner surface of the peripheral wall to which the potential is applied. An image exposure based on the M image signal is incident. As a result, the electrostatic latent image formed on the peripheral wall surface is developed into an M toner image by non-contact reversal development by the developing device 13M, so that the Y toner image and the M toner image are superimposed on the surface of the image forming body 10. A two-color image consisting of
[0049]
Similarly, the peripheral wall of the image forming body 10 that holds the two-color image is subjected to charging by the charger 11C, the image exposure means 12C, and the developer 13C, and the image exposure incidence and development to form a C toner image on the surface. Thus, a three-color image formed by superposing three toner images of Y, M, and C is formed. Further, if necessary, the peripheral wall of the image forming body 10 that holds a three-color image is similarly subjected to charging by the charger 11K, the image exposure means 12K, and the developing device 13K, image exposure incident and development, and K toner on the surface. By forming an image, a four-color image formed by superposing four toner images of Y, M, C, and K is formed. That is, a three-color or four-color image is formed on the peripheral surface within one rotation of the image forming body 10.
[0050]
As described above, in the color image forming apparatus of the present invention, the image exposure units 12Y to 12K enter image exposure from the inside of the image forming body 10 through the transparent substrate to the organic photosensitive layer. The image exposures corresponding to the second, third, and fourth colors are also incident without being affected by the previously formed toner image to form an electrostatic latent image that gives a similar clear toner image. When developing with the developing units 13Y to 13K, a developing bias with direct current or further alternating current is applied to the developing sleeve 130, whereby the toner is transferred from the one-component or two-component developer layer on the developing sleeve 130 to the transparent conductive layer. The non-contact reversal development is performed without flying over and adhering to the grounded image forming body 10 and affecting the previously formed toner image.
[0051]
Thus, the three-color or four-color image formed on the peripheral surface of the image forming body 10 is transferred to the peripheral surface of the intermediate transfer body 14 used for reducing the diameter of the image forming body 10. This intermediate transfer member 14 has an electrical resistance of 10 ⁸ -10 ¹¹ It consists of a belt in which a Teflon layer having a similar resistance value is provided as a separation surface layer on a urethane rubber layer of Ω · cm and a thickness of 100 to 500 μm, and is stretched by rollers 14A, 14B, 14C and 14D. And the roller 14B are brought into contact with the peripheral surface of the image forming body 10 to form a transfer area of the color image, and the transfer between the roller 14C and the transfer roller 15 facing the roller 14C is transferred to a transfer material such as transfer paper. As a region, the power transmitted to the roller 14D is rotated counterclockwise in FIG. 1 in synchronization with the peripheral speed of the image forming body 10.
[0052]
The color image adhering to the outer peripheral surface of the image forming body 10 is guided so as to come into contact with the outer peripheral surface of the image forming body 10 by a grounded roller 14A, and a bias voltage of 1 to 2 kV having a polarity opposite to that of toner charging is applied. The toner is efficiently transferred to the intermediate transfer body 14 in the transfer area guided away from the outer peripheral surface of the image forming body 10 by the roller 14B, without being scattered, and conveyed to the transfer area by the intermediate transfer body 14. It is.
[0053]
On the other hand, the transfer paper P is carried out by the action of the paper feed roller 17 of the paper feed cassette (not shown) and fed to the timing roller 18, and transferred by the transfer roller 15 in synchronization with the conveyance of the color image on the intermediate transfer body 14. Paper is fed to the area.
[0054]
The transfer roller 15 rotates counterclockwise in synchronism with the peripheral speed of the intermediate transfer member 14, and presses the fed transfer paper P against the intermediate transfer member 14 with the roller 14C in a grounded state. The color image on the intermediate transfer body 14 is transferred onto the transfer paper P by applying a bias voltage of 1 to 2 kV having a polarity opposite to that of the toner.
[0055]
The transfer paper P to which the color image has been transferred is discharged, transported to the fixing device 21 via the transport plate 19, and is heated and compressed between the heat roller 21A and the pressure roller 21B to fix the toner, and then discharged. The paper is discharged out of the apparatus via the paper roller 22.
[0056]
The cleaning blades of the cleaning device 100, the cleaning device 140, and the cleaning device 150 are always in contact with the surfaces of the image forming body 10, the intermediate transfer body 14, and the transfer roller 15 after the color image transfer, so that residual toner or the like adheres. Since the dirt is removed, all surfaces are always kept clean. The toner collected by the cleaning device 100 and the cleaning device 140 is stored in a waste toner storage container by a toner transfer tube (not shown) with a built-in transfer screw.
[0057]
【The invention's effect】
As described above in detail, in a color image forming apparatus in which a plurality of image exposure means having the structure according to claims 1 to 23 of the present invention are housed in an image forming body, an image is attached to an optical system support means to which the image exposure means is attached. Since the image forming body is rotatably supported and integrated, the positional accuracy of the relationship between the inner peripheral surface of the image forming body and the plurality of image exposure means is stably maintained accurately, and the image forming body rotates smoothly. Therefore, a clear color image without color misregistration can be easily formed, and the integrated optical system support means can be easily assembled, disassembled, maintained, and attached to and detached from the apparatus main body. .
[0058]
Further, in the apparatus having the constitution of the fifth to eleventh aspects, a lightening hole or a groove is provided in the image forming body bearing support portion of the optical system supporting means, and this is used for air cooling of the electric wiring of the image exposing means or the image forming body. Since the integrated optical system support means is reduced in weight, it is possible to form a more stable and clear color image, and it is easier to assemble and disassemble the integrated optical system support means. It also has the effect of being able to do it. In the apparatus having the constitutions of claims 12 to 18, since the optical system support means is hollow, the same weight reduction and more stable color image formation, assembling and disassembling can be obtained. Further, in the apparatus having the structure of claim 19 and claims 21 to 23 attached thereto, the exposure means fixing part of the optical system support means forms a space between the fixing parts for fixing the both ends of the image exposure means. This also brings about an effect of reducing the weight of the integrated optical system support means.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an example of a color image forming apparatus according to the present invention.
FIG. 2 is a partial front view showing an attached state of an optical system support unit integrated with an image forming body of a color image forming apparatus according to the present invention.
FIG. 3 is a partial sectional view in the axial direction showing an attached state of an optical system support means in which the image forming bodies according to the examples of claims 1 to 11 and claims 20 to 23 are integrated.
FIG. 4 is a partial cross-sectional view in the axial direction showing an attached state of an optical system support unit in which an image forming body according to an example of claims 12 to 18 is integrated.
FIG. 5 is a partial sectional view in the axial direction showing an attached state of an optical system support unit in which the image forming bodies according to the examples of claim 19 and claims 21 to 23 are integrated;
FIG. 6 is a partial axial sectional view showing an attached state of an optical system support unit integrated with an image forming body according to an example of claims 20 to 23;
[Explanation of symbols]
10 Image forming body
10A end ring
10B end gear ring
10C bearing
10G drum gear
11Y-11K charger
12Y-12K image exposure means
13Y-13K Developer
130 Development Sleeve
133-136 Sleeve gear
30 cavities
31 Unit shaft
31H hollow hole
32, 33 Bracket
320, 330 Exposure means fixing part
321,331 Image forming member bearing support
35 U-shaped bracket
35B Connecting beam
36 phase pin
38 Front plate
70A Front side plate
70B back side plate
71, 73, 74 Guide support rail
72 Bearing seat

Claims

An optical system support means equipped with a plurality of image exposure means, a color image having a drum-shaped image forming body which accommodates the image exposure means therein and a plurality of developing units arranged around the said imaging member In the forming apparatus, the pair of brackets fixed to the shaft, which constitute the optical system support means , are the portions where the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the portions which are not opposed to each other and are apart from each other. The image forming body bearing support portion rotatably supports the image forming body, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, and the image forming body bearing support portion has one end side. said image forming body and a rotatably supported, to be attached to the main body by the shaft which projects axially outward from said imaging member bearing the supporting portion is held by the apparatus main body side plate having a passive gear on the outer periphery of the Features a color Image forming apparatus.

2. The color image forming apparatus according to claim 1, wherein an outer diameter of an axis of the optical system support means held by the apparatus main body side plate is in a range of 10 to 30 mm.

Claim the length of the portion axis of the optical system support means is held in the apparatus main body side plates projecting axially outward from the image forming bearing support portion, characterized in that the range of 20~100mm The color image forming apparatus according to 1 or 2.

4. The color image forming apparatus according to claim 1, wherein electrical wiring to the image exposure unit is performed from a side opposite to a side where the passive gear is located . 5.

An optical system support means equipped with a plurality of image exposure means, a color image having a drum-shaped image forming body which accommodates the image exposure means therein and a plurality of developing units arranged around the said imaging member In the forming apparatus, the pair of brackets fixed to the shaft, which constitute the optical system support means , are the portions where the image exposure means is fixed to the exposure means fixing portion which is a close portion facing each other, and the portions which are not opposed to each other and are apart from each other. An image forming body in which the image forming body is rotatably supported by an image forming body bearing support portion, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion and has a lightening hole or a groove. The image forming body having a bearing support portion, the image forming body bearing support portion rotatably supporting the image forming body having a passive gear on the outer periphery on one end side, and projecting outward in the axial direction from the image forming body bearing support portion. holding the shaft in the apparatus main assembly, Color image forming apparatus characterized by being mounted on the apparatus main body so.

The color image forming apparatus according to claim 5, wherein an outer diameter of the image forming body bearing support portion is in a range of 30 to 100 mm.

7. A color image forming apparatus according to claim 5, wherein an electrical wiring of the image exposure means is passed through a lightening hole or groove of the image forming body bearing support portion.

The color image forming apparatus according to claim 7 the electrical wiring of the image exposure means, wherein the passive gear of said image forming body is connected to the power supply on the opposite side in the axial direction to the side where it is located.

The color image forming apparatus according to claim 5, wherein an air flow is passed through a lightening hole or groove of the image forming body bearing support portion.

The air flow is characterized by flowing into the lightening hole or groove of the image forming bearing support part of the optical system support means from the opposite side in the axial direction to the side where the passive gear of said image forming body is located The color image forming apparatus according to claim 9.

The color image forming apparatus according to claim 9 or 10, wherein a cooling fin is provided in a lightening hole or groove of the image forming body bearing support portion.

An optical system support means equipped with a plurality of image exposure means, a color image having a drum-shaped image forming body which accommodates the image exposure means therein and a plurality of developing units arranged around the said imaging member In the forming device,
The pair of brackets fixed to the shaft, which constitute the optical system support means , have the image exposure means fixed to the exposure means fixing portion that is a close portion facing each other, and the image forming body bearings that are separated from each other but not facing each other said imaging member to the support portion is supported rotatably, larger than the diameter of the diameter of said image forming body bearing supports said exposure means fixed part, the axis of the optical system support means is hollow, said image It said image forming body having a passive gear on the outer periphery of the one end side by the forming bearing support portion rotatably supporting the rotation, to hold the hollow shaft which projects axially outward from the image forming bearing support portion in the apparatus main assembly, And a color image forming apparatus mounted on the apparatus main body.

The color image forming apparatus according to claim 12, wherein an outer diameter of a hollow shaft of the optical system supporting unit held on the apparatus main body side plate is in a range of 30 to 80 mm.

14. The color image forming apparatus according to claim 12, wherein an electric wiring of the image exposure unit is passed through a hollow hole of a hollow shaft of the optical system support unit.

15. The color image forming apparatus according to claim 14, wherein the electrical wiring of the image exposure means is connected to a power source on the side opposite to the side where the passive gear of the image forming body is located .

The color image forming apparatus according to claim 12, wherein an air flow is passed through a hollow hole of a hollow shaft of the optical system support unit.

The color image forming apparatus according to claim 16, wherein the air flow flows into a hollow hole of a hollow shaft of the optical system support means from a side opposite to a side where the passive gear of the image forming body is located .

The color image forming apparatus according to claim 16 or 17, wherein a cooling fin is provided in a hollow hole of a hollow shaft portion of the optical system support means.

Color image forming apparatus comprising: an optical system supporting unit having a plurality of image exposing units; a drum-shaped image forming body containing the image exposing unit therein; and a plurality of developing units disposed around the image forming unit. In the apparatus, the optical system support means may be configured such that an exposure means fixing portion to which the image exposure means is attached forms a space between the fixed portions for fixing both ends of the image exposure means, and the electric power of the image exposure means is set in the cavity. An image forming body bearing support portion is provided on the outer side in the axial direction from the exposure means fixing portion so as to face the connection portion of the wiring, and the image forming body is rotatably supported by the image forming body bearing support portion. A color image forming apparatus, wherein the shaft projecting outward in the axial direction from the body bearing support portion is attached to the apparatus main body while being held by the apparatus main body side plate.

Color image forming with the optical system support means equipped with a plurality of image exposure means, a drum-shaped image forming body which accommodates the image exposure means therein, a plurality of developing devices arranged around the said imaging member In the apparatus, the pair of brackets fixed to the shaft, which constitute the optical system support means, have an image exposure means fixed to an exposure means fixing portion that is a close portion facing each other, and images that are separated from each other but not facing each other. The image forming body is rotatably supported by the forming body bearing support portion, and the diameter of the image forming body bearing support portion is larger than the diameter of the exposure means fixing portion, and the connecting portion of the electric wiring is positioned on the end face or the side surface. color image forming apparatus to said image exposing means and fixed with, and wherein said shaft device being mounted on the apparatus main body is held by the main body side plate which projects axially outward from the image forming bearing support.

21. The color image forming apparatus according to claim 19, wherein the image forming body supported by the image forming body bearing support portion has a passive gear on an outer periphery on one end side.

The electrical wiring of the image exposure means passes through the inside of the bearing supported by the image forming body bearing support portion of the optical system support means to connect the connection portion of the image exposure means and a power source. The color image forming apparatus according to 21.

23. The color image forming apparatus according to claim 22, wherein the power source of the electric wiring of the image exposure means is on the opposite side in the axial direction from the side where the passive gear of the image forming body is located .