JP4219183B2

JP4219183B2 - Optical element retracting mechanism of lens barrel

Info

Publication number: JP4219183B2
Application number: JP2003025416A
Authority: JP
Inventors: 博野村
Original assignee: Hoya Corp
Current assignee: Hoya Corp
Priority date: 2003-02-03
Filing date: 2003-02-03
Publication date: 2009-02-04
Anticipated expiration: 2023-02-03
Also published as: JP2004233922A

Description

【０００１】
【技術分野】
本発明は、撮影光学系を構成する複数の光学要素の一部を、収納状態で撮影光軸位置と異なる位置に退避させるレンズ鏡筒の光学要素退避機構に関する。
【０００２】
【従来技術及びその問題点】
カメラの小型化の要求はとどまるところがなく、非撮影時にレンズ鏡筒を短縮させる収納タイプのレンズ鏡筒では、一層の収納長の短縮が求められている。これを達成すべく本出願人は、収納時において撮影光学系の一部の光学要素を撮影光軸と異なる位置に退避させ、かつ該退避光学要素を他の光学要素と共に光軸方向後方に後退させるレンズ鏡筒を提案した（特許第３７７１９０９号）。このように複雑な動作を行う退避光学要素を駆動するための機構は、特に高い動作精度が要求される。また、簡単な構造で高精度に退避光学要素の位置を調整できることが求められる。
【０００３】
【特許文献】
特許第３７７１９０９号
【０００４】
【発明の目的】
本発明は、収納状態で撮影光軸とは異なる位置に退避されかつ後退する光学要素を、高い精度で駆動及び位置調整することが可能なレンズ鏡筒の光学要素退避機構を提供することを目的とする。
【０００５】
【発明の概要】
本発明は、撮影光学系を構成する複数の光学要素；この撮影光学系の光軸方向に直進案内され、撮影状態から収納状態になるとき結像面方向に後退する直進進退環；複数の光学要素の一部をなす退避光学要素を支持し、直進進退環の内側に設けた回動中心軸により回動可能に支持される揺動部材；この揺動部材を、撮影状態では上記退避光学要素を他の光学要素と同一光軸上に位置させて保持し、該揺動部材が直進進退環と共に収納方向へ後退するとき回動させて、上記退避光学要素を他の光学要素の光軸とは異なる位置に退避させる位置制御機構；直進進退環を前後から挟着して揺動部材の回動中心軸の前後端部を支持する、光軸方向に離間した一対の軸支持板；該一対の軸支持板を直進進退環に固定し、固定解除状態で光軸と直交する方向への移動を許す支持板固定手段；一対の軸支持板の対向する位置にその長軸が互いに平行になるように形成した、一対の第１の長孔と、該第１の長孔の長軸と直交する長軸を有する一対の第２の長孔；それぞれが直進進退環に設けられた偏心軸支持孔に対して光軸と平行な軸を中心として回転可能に挿入支持された、一対の第１の長孔に摺動可能に係合する一対の偏心ピンを両端に有する第１の偏心軸部材と、一対の第２の長孔に摺動可能に係合する一対の偏心ピンを両端に有する第２の偏心軸部材；及び、一対の軸支持板と直進進退環に設けた、第１及び第２の偏心軸部材を回転させたとき光軸と直交する平面内での各軸支持板の移動方向を規制する移動ガイド手段；を有し、少なくとも一方の軸支持板における上記第１と第２の長孔を光軸方向への貫通孔とし、第１の偏心軸部材両端の一対の偏心ピンと、第２の偏心軸部材両端の一対の偏心ピンのそれぞれのうち、貫通孔に係合する側の端部に、直進進退環の前方または後方の開口部から回転操作可能な回転操作部を設けたことを特徴としている。
【０００６】
第１と第２の偏心軸部材の回転操作部は、収納方向とは反対の前方の偏心ピン側に形成することが好ましい。さらに直進進退環の外側を覆い該直進進退環の前方に内径フランジを位置させた外側筒を有する場合、該外側筒の内径フランジに、第１の偏心軸部材と第２の偏心軸部材の回転操作部の前方に位置し光軸方向に貫通する第１と第２の回転操作孔を形成すると、外側筒を外さずに各偏心軸部材を回転操作することができるので好ましい。
【０００７】
一対の軸支持板にそれぞれ光軸方向に貫通して形成したビス螺合孔と、該ビス螺合孔に同時に螺合する共通の固定ビスとから支持板固定手段を構成した上で、該固定ビスにおける第１と第２の偏心軸部材の回転操作部と同方向に向く端部を回転操作部とすることで、さらに作業性が向上する。この固定ビスの回転操作部の前方に上記外側筒の内径フランジが位置する場合には、この内径フランジに固定ビス操作用の第３の回転操作孔を形成するとよい。
【０００８】
揺動部材の回動中心軸は、撮影光学系の光軸に平行であることが好ましい。この態様において揺動部材の位置制御機構としてさらに、揺動部材を回転方向に付勢する付勢手段と、光軸と平行な回転中心で回転可能に直進進退環に支持され、この回転中心に対して偏心する偏心ピンを揺動部材に係合させて付勢方向への回動端を決める第３の偏心軸部材とを設け、第１及び第２の偏心軸部材とは別に、第３の偏心軸部材の回転による退避光学要素の位置調整機能を持たせてもよい。この場合、第３の偏心軸部材は、第１及び第２の偏心軸部材の回転操作部と同方向に向く端部に回転操作可能な回転操作部を有していると操作性が良く好ましい。この第３の偏心軸部材の回転操作部の前方に上記外側筒の内径フランジが位置する場合には、この内径フランジに第３の偏心軸部材操作用の第４の回転操作孔を形成するとよい。
【０００９】
外側筒の内径フランジの前部にはレンズバリヤ機構が着脱され、該レンズバリヤ機構によって上記の各回転操作孔が覆われるようにすることが好ましい。
また、外側筒が退避光学要素の前方に位置する前方光学要素をしており、撮影状態からの収納動作時に直進進退環と共に後退することが好ましい。
【００１０】
偏心軸部材や固定ビスの回転操作部は、例えば、ドライバが係合可能な凹部とすることができる。
【００１１】
本発明は、撮影状態で退避光学要素の後方に位置する後方光学要素を有し、収納状態では、退避光学要素が、後方光学要素と光軸方向位置を重複させて位置されるタイプのレンズ鏡筒に好適である。
【００１２】
本発明のレンズ鏡筒では、退避光学要素はレンズ群とすることができる。
【００１３】
本発明のレンズ鏡筒はまた、撮影光学系を構成する複数の光学要素；この撮影光学系の光軸方向に直進案内され、撮影状態から収納状態になるとき結像面方向に後退する直進進退環；この直進進退環を前後から挟着して光軸方向に離間する一対の軸支持板と、該一対の軸支持板に両端部が支持される回動中心軸；直進進退環の内側に該回動中心軸により回動可能に支持される、複数の光学要素の一部をなす退避光学要素を支持した揺動部材；この揺動部材を、撮影状態では退避光学要素を他の光学要素と同一光軸上に位置させて保持し、該揺動部材が直進進退環と共に収納方向へ後退するとき回動させて、退避光学要素を他の光学要素の光軸とは異なる位置に退避させる位置制御機構；一対の軸支持板の対向する位置にその長軸が互いに平行になるように形成した、一対の第１の長孔と、該第１の長孔の長軸と直交する長軸を有する前後一対の第２の長孔；それぞれが直進進退環に設けられた偏心軸支持孔に対して光軸と平行な軸を中心として回転可能に挿入支持された、一対の第１の長孔に摺動可能に係合する一対の偏心ピンを両端に有する第１の偏心軸部材と、一対の第２の長孔に摺動可能に係合する一対の偏心ピンを両端に有する第２の偏心軸部材；及び、一対の軸支持板を光軸方向に貫通螺合して直進進退環に固定させ、固定解除状態では、第１と第２の偏心軸部材の回転に応じて光軸と直交する方向への一対の軸支持板の移動を許す固定ビス；を有し、第１及び第２の偏心軸部材と固定ビスの、前後いずれか同方向の端部を直進進退環の前方または後方の開口部から回転操作可能としたことを特徴としている。
【００１４】
揺動部材の回動中心軸は撮影光学系の光軸に平行であることが好ましく、この態様においてさらに、第１及び第２の偏心軸部材とは別に、揺動部材の位置を調整する第３の偏心軸部材を設け、この第３の偏心軸部材にも、第１及び第２の偏心軸部材と同方向から回転操作可能な回転操作部を設けるとよい。
【００１６】
【発明の実施の形態】
［レンズ鏡筒の全体の説明］
まず、図１ないし図１９について、本実施形態のズームレンズ鏡筒７１の全体構造を説明する。この実施形態は、デジタルカメラ７０用のズームレンズ鏡筒に本発明を適用した実施形態であり、撮影光学系は、物体側から順に、第１レンズ群（前方光学要素）ＬＧ１、シャッタＳ及び絞りＡ、第２レンズ群（退避光学要素）ＬＧ２、第３レンズ群（後方光学要素）ＬＧ３、ローパスフィルタ（フィルタ類）ＬＧ４及び固体撮像素子（以下、ＣＣＤ）６０からなっている。撮影光学系の光軸はＺ１である。この撮影光軸Ｚ１は、ズームレンズ鏡筒７１の中心軸Ｚ０と平行であり、かつ該鏡筒中心軸Ｚ０に対して偏心している。ズーミングは、第１レンズ群ＬＧ１と第２レンズ群ＬＧ２を撮影光軸Ｚ１方向に所定の軌跡で進退させ、フォーカシングは同方向への第３レンズ群ＬＧ３の移動で行う。なお、以下の説明中で「光軸方向」という記載は、特に断りがなければ撮影光軸Ｚ１と平行な方向を意味している。
【００１７】
図６及び図７に示すように、カメラボディ７２内に固定環２２が固定され、この固定環２２の後部にＣＣＤホルダ２１が固定されている。ＣＣＤホルダ２１上にはＣＣＤベース板６２を介してＣＣＤ６０が支持され、ＣＣＤ６０の前部に、フィルタホルダ７３とパッキン６１を介してローパスフィルタＬＧ４が支持されている。
【００１８】
固定環２２内には、第３レンズ群ＬＧ３を保持するＡＦレンズ枠（３群レンズ枠）５１が光軸方向に直進移動可能に支持されている。すなわち、固定環２２とＣＣＤホルダ２１には、撮影光軸Ｚ１と平行な一対のＡＦガイド軸５２、５３の前端部と後端部がそれぞれ固定されており、このＡＦガイド軸５２、５３に対してそれぞれ、ＡＦレンズ枠５１に形成したガイド孔５１ａ、５１ｂが摺動可能に嵌まっている。本実施形態では、ＡＦガイド軸５２がメインのガイド軸で、ＡＦガイド軸５３はＡＦレンズ枠５１の回転規制用に設けられている。ＡＦレンズ枠５１に固定したＡＦナット５４に対し、ＡＦモータ１６０のドライブシャフトに形成した送りねじが螺合しており、該ドライブシャフトを回転させると、送りねじとＡＦナット５４の螺合関係によってＡＦレンズ枠５１が光軸方向に進退される。ＡＦレンズ枠５１は、ＡＦ枠付勢ばね５５によって光軸方向の前方に付勢されている。
【００１９】
図５に示すように、固定環２２の上部には、ズームモータ１５０と減速ギヤボックス７４が支持されている。減速ギヤボックス７４は内部に減速ギヤ列を有し、ズームモータ１５０の駆動力をズームギヤ２８に伝える。ズームギヤ２８は、撮影光軸Ｚ１と平行なズームギヤ軸２９によって固定環２２に枢着されている。ズームモータ１５０とＡＦモータ１６０は、固定環２２の外周面に配設したレンズ駆動制御ＦＰＣ（フレキシブルプリント回路）基板７５を介して、カメラの制御回路１４０（図１９）により制御される。
【００２０】
固定環２２の内周面には、雌ヘリコイド２２ａ、撮影光軸Ｚ１と平行な３本の直進案内溝２２ｂ、雌ヘリコイド２２ａと平行な３本のリード溝２２ｃ、及び各リード溝２２ｃの前端部に連通する周方向への回転摺動溝２２ｄが形成されている。雌ヘリコイド２２ａは、回転摺動溝２２ｄが形成されている固定環２２前部の一部領域には形成されていない（図８参照）。
【００２１】
ヘリコイド環１８は、雌ヘリコイド２２ａに螺合する雄ヘリコイド１８ａと、リード溝２２ｃ及び回転摺動溝２２ｄに係合する回転摺動突起１８ｂとを外周面に有している（図４、図９）。雄ヘリコイド１８ａ上には、撮影光軸Ｚ１と平行なギヤ歯を有するスパーギヤ部１８ｃが形成されており、スパーギヤ部１８ｃはズームギヤ２８に対して螺合する。従って、ズームギヤ２８によって回転力を与えたときヘリコイド環１８は、雌ヘリコイド２２ａと雄ヘリコイド１８ａが螺合関係にある状態では回転しながら光軸方向へ進退し、ある程度前方に移動すると、雄ヘリコイド１８ａが雌ヘリコイド２２ａから外れ、回転摺動溝２２ｄと回転摺動突起１８ｂの係合関係によって鏡筒中心軸Ｚ０を中心とする周方向回転のみを行う。なお、雌ヘリコイド２２ａは、各リード溝２２ｃを挟む一対のヘリコイド山の周方向間隔が他のヘリコイド山の周方向間隔よりも広くなっており、雄ヘリコイド１８ａは、この周方向間隔の広いヘリコイド山に係合するべく、回転摺動突起１８ｂの後方に位置する３つのヘリコイド山１８ａ-Ｗが他のヘリコイド山よりも周方向に幅広になっている（図８、図９）。固定環２２には、回転摺動溝２２ｄと外周面とを貫通するストッパ挿脱孔２２ｅが形成され、このストッパ挿脱孔２２ｅに対し、撮影領域を越えるヘリコイド環１８の回動を規制するための鏡筒ストッパ２６が着脱可能となっている。
【００２２】
ヘリコイド環１８の前端部内周面に形成した回転伝達凹部１８ｄ（図４、図１０）に対し、第３外筒１５の後端部から後方に突設した回転伝達突起１５ａ（図１１）が嵌入されている。回転伝達凹部１８ｄと回転伝達突起１５ａはそれぞれ、周方向に位置を異ならせて３箇所設けられており、周方向位置が対応するそれぞれの回転伝達突起１５ａと回転伝達凹部１８ｄは、鏡筒中心軸Ｚ０に沿う方向への相対摺動は可能に結合し、該鏡筒中心軸Ｚ０を中心とする周方向には相対回動不能に結合されている。すなわち、第３外筒１５とヘリコイド環１８は一体に回転する。また、ヘリコイド環１８には、回転摺動突起１８ｂの内径側の一部領域を切り欠いて嵌合凹部１８ｅが形成されており、該嵌合凹部１８ｅに嵌合する嵌合突起１５ｂは、回転摺動突起１８ｂが回転摺動溝２２ｄに係合するとき、同時に回転摺動溝２２ｄに係合する（図６のズームレンズ鏡筒上半断面参照）。
【００２３】
第３外筒１５とヘリコイド環１８の間には、互いを光軸延長上での離間方向へ付勢する３つの離間方向付勢ばね２５が設けられている。離間方向付勢ばね２５は圧縮コイルばねからなり、その後端部がヘリコイド環１８の前端部に開口するばね挿入凹部１８ｆに収納され、前端部が第３外筒１５のばね当付凹部１５ｃに当接している。この離間方向付勢ばね２５によって、回転摺動溝２２ｄの前側壁面に向けて嵌合突起１５ｂを押圧し、かつ回転摺動溝２２ｄの後側壁面に向けて回転摺動突起１８ｂを押圧することで、固定環２２に対する第３外筒１５とヘリコイド環１８の光軸方向のバックラッシュが除去される。
【００２４】
第３外筒１５の内周面には、内径方向に突設された相対回動案内突起１５ｄと、鏡筒中心軸Ｚ０を中心とする周方向溝１５ｅと、撮影光軸Ｚ１と平行な３本のローラ嵌合溝１５ｆとが形成されている（図４、図１１）。相対回動案内突起１５ｄは、周方向に位置を異ならせて複数設けられている。ローラ嵌合溝１５ｆは、回転伝達突起１５ａに対応する周方向位置に形成されており、その後端部は、回転伝達突起１５ａを貫通して後方へ向け開口されている。また、ヘリコイド環１８の内周面には鏡筒中心軸Ｚ０を中心とする周方向溝１８ｇが形成されている（図４、図１０）。この第３外筒１５とヘリコイド環１８の結合体の内側には直進案内環１４が支持される。直進案内環１４の外周面には光軸方向の後方から順に、該径方向へ突出する３つの直進案内突起１４ａと、それぞれ周方向に位置を異ならせて複数設けた相対回動案内突起１４ｂ及び１４ｃと、鏡筒中心軸Ｚ０を中心とする周方向溝１４ｄとが形成されている（図４、図１２）。直進案内環１４は、直進案内突起１４ａを直進案内溝２２ｂに係合させることで、固定環２２に対し光軸方向に直進案内される。また第３外筒１５は、周方向溝１５ｅを相対回動案内突起１４ｃに係合させ、相対回動案内突起１５ｄを周方向溝１４ｄに係合させることで、直進案内環１４に対して相対回動可能に結合される。周方向溝１５ｅ、１４ｄと相対回動案内突起１４ｃ、１５ｄはそれぞれ、光軸方向には若干相対移動可能なように遊嵌している。さらにヘリコイド環１８も、周方向溝１８ｇを相対回動案内突起１４ｂに係合させることで、直進案内環１４に対して相対回動は可能に結合される。周方向溝１８ｇと相対回動案内突起１４ｂは光軸方向には若干相対移動可能なように遊嵌している。
【００２５】
直進案内環１４には、内周面と外周面を貫通する３つのローラ案内貫通溝１４ｅが形成されている。各ローラ案内貫通溝１４ｅは、図１２に示すように、周方向へ向け形成された平行な前後の周方向溝部１４ｅ-１、１４ｅ-２と、この両周方向溝部１４ｅ-１及び１４ｅ-２を接続する、上記雌ヘリコイド２２ａと平行なリード溝部１４ｅ-３とを有する。それぞれのローラ案内貫通溝１４ｅに対し、カム環１１の外周面に設けたカム環ローラ３２が嵌まっている。カム環ローラ３２は、ローラ固定ねじ３２ａを介してカム環１１に固定されており、周方向へ位置を異ならせて３つ設けられている。カム環ローラ３２はさらに、ローラ案内貫通溝１４ｅを貫通して第３外筒１５内周面のローラ嵌合溝１５ｆに嵌まっている。各ローラ嵌合溝１５ｆの前端部付近には、ローラ付勢ばね１７に設けた３つのローラ押圧片１７ａが嵌っている（図１１）。ローラ押圧片１７ａは、カム環ローラ３２が周方向溝部１４ｅ-１に係合するときに該カム環ローラ３２に当接して後方へ押圧し、カム環ローラ３２とローラ案内貫通溝１４ｅ（周方向溝部１４ｅ-１）との間のバックラッシュを取る。
【００２６】
以上の構造から、固定環２２からカム環１１までの繰り出しの態様が理解される。すなわち、ズームモータ１５０によってズームギヤ２８を鏡筒繰出方向に回転駆動すると、雌ヘリコイド２２ａと雄ヘリコイド１８ａの関係によってヘリコイド環１８が回転しながら前方に繰り出される。ヘリコイド環１８と第３外筒１５はそれぞれ、周方向溝１４ｄ、１５ｅ及び１８ｇと相対回動案内突起１４ｂ、１４ｃ及び１５ｄの係合関係によって、直進案内環１４に対して相対回動可能かつ回転軸方向（鏡筒中心軸Ｚ０に沿う方向）へは共に移動するように結合されているため、ヘリコイド環１８が回転繰出されると、第３外筒１５も同方向に回転しながら前方に繰り出され、直進案内環１４はヘリコイド環１８及び第３外筒１５と共に前方へ直進移動する。また、第３外筒１５の回転力はローラ嵌合溝１５ｆとカム環ローラ３２を介してカム環１１に伝達される。カム環ローラ３２はローラ案内貫通溝１４ｅにも嵌まっているため、直進案内環１４に対してカム環１１は、リード溝部１４ｅ-３の形状に従って回転しながら前方に繰り出される。前述の通り、直進案内環１４自体も第３外筒１５及びヘリコイド環１８と共に前方に直進移動しているため、結果としてカム環１１には、リード溝部１４ｅ-３に従う回転繰出分と、直進案内環１４の前方への直進移動分とを合わせた光軸方向移動量が与えられる。
【００２７】
以上の繰出動作は雄ヘリコイド１８ａが雌ヘリコイド２２ａと螺合した状態で行われ、このとき回転摺動突起１８ｂはリード溝２２ｃ内を移動している。ヘリコイドによって所定量繰り出されると、雄ヘリコイド１８ａと雌ヘリコイド２２ａの螺合が解除されて、やがて回転摺動突起１８ｂがリード溝２２ｃから回転摺動溝２２ｄ内へ入る。このとき同時に、カム環ローラ３２はローラ案内貫通溝１４ｅの周方向溝部１４ｅ-１に入る。すると、ヘリコイド環１８及び第３外筒１５は、ヘリコイドによる回転繰出力が作用しなくなるため、ズームギヤ２８の駆動に応じて光軸方向の一定位置で回動のみを行うようになる。この状態では直進案内環１４が停止し、かつカム環ローラ３２が周方向溝部１４ｅ-１内に移行したため、カム環１１にも前方への移動力が与えられなくなり、カム環１１は第３外筒１５の回転に応じて一定位置で回動のみ行うようになる。
【００２８】
ズームギヤ２８を鏡筒収納方向に回転駆動させると、以上と逆の動作が行われる。カム環ローラ３２がローラ案内貫通溝１４ｅの周方向溝部１４ｅ-２に入るまでヘリコイド環１８に回転を与えると、以上の各鏡筒部材が図７に示す位置まで後退する。
【００２９】
カム環１１より先の構造をさらに説明する。直進案内環１４の内周面には、撮影光軸Ｚ１と平行な３つの第１直進案内溝１４ｆ及び６つの第２直進案内溝１４ｇが、それぞれ周方向に位置を異ならせて形成されている。第１直進案内溝１４ｆは、６つのうち３つの第２直進案内溝１４ｇの両側に位置する一対の溝部からなっており、この３つの第１直進案内溝１４ｆに対し、２群直進案内環１０に設けた３つの股状突起１０ａ（図３、図１５）が摺動可能に係合している。一方、第２直進案内溝１４ｇに対しては、第２外筒１３の後端部外周面に突設した６つの直進案内突起１３ａ（図２、図１７）が摺動可能に係合している。したがって、第２外筒１３と２群直進案内環１０はいずれも、直進案内環１４を介して光軸方向に直進案内されている。
【００３０】
２群直進案内環１０は、第２レンズ群ＬＧ２を支持する２群レンズ移動枠（直進進退環、支持体）８を直進案内するための部材であり、第２外筒１３は、第１レンズ群ＬＧ１を支持する第１外筒（外側筒）１２を直進案内するための部材である。
【００３１】
まず第２レンズ群ＬＧ２の支持構造を説明する。２群直進案内環１０は、３つの股状突起１０ａを接続するリング部１０ｂから前方へ向けて、３つの直進案内キー１０ｃを突出させている（図３、図１５）。図６及び図７に示すように、リング部１０ｂの外縁部は、カム環１１の後端部内周面に形成した周方向溝１１ｅに対し相対回転は可能で光軸方向の相対移動は不能に係合しており、直進案内キー１０ｃはカム環１１の内側に延出されている。各直進案内キー１０ｃは、撮影光軸Ｚ１と平行な一対のガイド面を側面に有しており、このガイド面を、カム環１１の内側に支持された２群レンズ移動枠８の直進案内溝８ａに係合させることによって、２群レンズ移動枠８を軸方向に直進案内している。直進案内溝８ａは、２群レンズ移動枠８の外周面側に形成されている。
【００３２】
カム環１１の内周面には２群案内カム溝１１ａが形成されている。図１４に示すように、２群案内カム溝１１ａは、光軸方向及び周方向に位置を異ならせた前方カム溝１１ａ-１と後方カム溝１１ａ-２からなっている。前方カム溝１１ａ-１と後方カム溝１１ａ-２はいずれも、同形状の基礎軌跡αをトレースして形成されたカム溝であるが、それぞれが基礎軌跡α全域をカバーしているのではなく、前方カム溝１１ａ-１と後方カム溝１１ａ-２では基礎軌跡α上に占める領域の一部が異なっている。基礎軌跡とは、ズーム領域及び収納用領域を含む全ての鏡筒使用領域（使用領域）と、鏡筒の組立分解用領域とを含む概念上のカム溝形状である。鏡筒使用領域とは、言い換えれば、カム機構によって移動が制御されうる領域のことであり、カム機構の組立分解領域と区別する意味で用いられている。また、ズーム領域とは、鏡筒使用領域の中でも特にワイド端とテレ端の間の移動を制御するための領域であり、収納用領域と区別する意味で用いられている。カム環１１には、一対の前方カム溝１１ａ-１と後方カム溝１１ａ-２を１グループとした場合、周方向に等間隔で３グループの２群案内カム溝１１ａが形成されている。
【００３３】
２群案内カム溝１１ａに対して、２群レンズ移動枠８の外周面に設けた２群用カムフォロア８ｂが係合している。２群案内カム溝１１ａと同様に２群用カムフォロア８ｂも、光軸方向及び周方向に位置を異ならせた一対の前方カムフォロア８ｂ-１と後方カムフォロア８ｂ-２を１グループとして周方向に等間隔で３グループが設けられており、各前方カムフォロア８ｂ-１は前方カム溝１１ａ-１に係合し、各後方カムフォロア８ｂ-２は後方カム溝１１ａ-２に係合するように光軸方向及び周方向の間隔が定められている。
【００３４】
２群レンズ移動枠８は２群直進案内環１０を介して光軸方向に直進案内されているため、カム環１１が回転すると、２群案内カム溝１１ａに従って、２群レンズ移動枠８が光軸方向へ所定の軌跡で移動する。
【００３５】
２群レンズ移動枠８の内側には、第２レンズ群ＬＧ２を保持する２群レンズ枠（揺動部材、被支持要素）６が支持されている。２群レンズ枠６は、一対の２群レンズ枠支持板（軸支持板、支持板）３６、３７に対し、２群回動軸（回動中心軸）３３を介して軸支されており、２群枠支持板３６、３７が支持板固定ビス（支持板固定手段）６６によって２群レンズ移動枠８に固定されている。２群回動軸３３は撮影光軸Ｚ１と平行でかつ撮影光軸Ｚ１に対して偏心しており、２群レンズ枠６は、２群回動軸３３を回動中心として、第２レンズ群ＬＧ２の光軸を撮影光軸Ｚ１と一致させる撮影用位置（図６）と、第２レンズ群ＬＧ２の光軸が撮影光軸Ｚ１から偏心した退避光軸Ｚ２となる収納用退避位置（図７）とに回動することができる。２群レンズ移動枠８には、２群レンズ枠６を上記撮影用位置で回動規制する回動規制ピン（位置制御機構、第３の偏心軸部材）３５が設けられていて、２群レンズ枠６は、２群レンズ枠戻しばね（位置制御機構）３９によって該回動規制ピン３５との当接方向へ回動付勢されている。軸方向押圧ばね３８は、２群レンズ枠６の光軸方向のバックラッシュ取りを行う。
【００３６】
２群レンズ枠６は、光軸方向には２群レンズ移動枠８と一体に移動する。ＣＣＤホルダ２１には２群レンズ枠６に係合可能な位置にカム突起（位置制御機構）２１ａ（図４）が前方に向けて突設されており、図７のように２群レンズ移動枠８が収納方向に移動してＣＣＤホルダ２１に接近すると、該カム突起２１ａの先端部に形成したカム面が、２群レンズ枠６に係合して上記の収納用退避位置に回動させる。この２群退避構造については後述する。
【００３７】
続いて第１レンズ群ＬＧ１の支持構造を説明する。直進案内環１４を介して光軸方向に直進案内された第２外筒１３の内周面には、周方向に位置を異ならせて３つの直進案内溝１３ｂが光軸方向へ形成されており、各直進案内溝１３ｂに対し、第１外筒１２の後端部付近の外周面に形成した３つの係合突起１２ａが摺動可能に嵌合している（図２、図１７及び図１８参照）。すなわち、第１外筒１２は、直進案内環１４と第２外筒１３を介して光軸方向に直進案内されている。また、第２外筒１３は後端部付近の内周面に、周方向へ向かう内径フランジ１３ｃを有し、この内径フランジ１３ｃがカム環１１の外周面に設けた周方向溝１１ｃに摺動可能に係合することで、第２外筒１３は、カム環１１に対して相対回転可能かつ光軸方向の相対移動は不能に結合されている。一方、第１外筒１２は、内径方向に突出する３つの１群用ローラ（カムフォロア）３１を有し、それぞれの１群用ローラ３１が、カム環１１の外周面に３本形成した１群案内カム溝１１ｂに摺動可能に嵌合している。
【００３８】
第１外筒１２内には、１群調整環２を介して１群レンズ枠１が支持されている。１群レンズ枠１には第１レンズ群ＬＧ１が固定され、その外周面に形成した雄調整ねじ１ａが、１群調整環２の内周面に形成した雌調整ねじ２ａに螺合している。この調整ねじの螺合位置を調整することよって、１群レンズ枠１は１群調整環２に対して光軸方向に位置調整可能となっている。
【００３９】
１群調整環２は外径方向に突出する一対の（図２には一つのみを図示）ガイド突起２ｂを有し、この一対のガイド突起２ｂが、第１外筒１２の内周面側に形成した一対の１群調整環ガイド溝１２ｂに摺動可能に係合している。１群調整環ガイド溝１２ｂは撮影光軸Ｚ１と平行に形成されており、該１群調整環ガイド溝１２ｂとガイド突起２ｂの係合関係によって、１群調整環２と１群レンズ枠１の結合体は、第１外筒１２に対して光軸方向の前後移動が可能になっている。第１外筒１２にはさらに、ガイド突起２ｂの前方を塞ぐように、１群抜止環３が抜止環固定ビス６４によって固定されている。１群抜止環３のばね受け部３ａとガイド突起２ｂとの間には、圧縮コイルばねからなる１群付勢ばね２４が設けられ、該１群付勢ばね２４によって１群調整環２は光軸方向後方に付勢されている。１群調整環２は、その前端部付近の外周面に突設した係合爪２ｃを、１群抜止環３の前面（図２に見えている側の面）に係合させることによって、第１外筒１２に対する光軸方向後方への最大移動位置が規制される（図６の上半断面参照）。一方、１群付勢ばね２４を圧縮させることによって、１群調整環２は光軸方向前方に若干量移動することができる。
【００４０】
第１レンズ群ＬＧ１と第２レンズ群ＬＧ２の間には、シャッタＳと絞りＡを有するシャッタユニット７６が支持されている。シャッタユニット７６は、２群レンズ移動枠８の内側に支持されており、シャッタＳと絞りＡは、第２レンズ群ＬＧ２との空気間隔が固定となっている。シャッタユニット７６を挟んだ前後位置には、シャッタＳと絞りＡを駆動する２つのアクチュエータ（不図示）が、それぞれ一つずつ配置されており、シャッタユニット７６からはこれらアクチュエータをカメラの制御回路１４０と接続するための露出制御ＦＰＣ（フレキシブルプリント回路）基板７７が延出されている。
【００４１】
第１外筒１２の前端部には、シャッタＳとは別に、非撮影時に撮影開口を閉じて撮影光学系（第１レンズ群ＬＧ１）を保護するためのレンズバリヤ機構が設けられる。レンズバリヤ機構は、鏡筒中心軸Ｚ０に対して偏心した位置に設けた回動軸を中心として回動可能な一対のバリヤ羽根１０４及び１０５と、該バリヤ羽根１０４、１０５を閉じ方向に付勢する一対のバリヤ付勢ばね１０６と、鏡筒中心軸Ｚ０を中心として回動可能で所定方向の回動によってバリヤ羽根１０４、１０５に係合して開かせるバリヤ駆動環１０３と、該バリヤ駆動環１０３をバリヤ開放方向に回動付勢するバリヤ駆動環付勢ばね１０７と、バリヤ羽根１０４、１０５とバリヤ駆動環１０３の間に位置するバリヤ押さえ板１０２とを備えている。バリヤ駆動環付勢ばね１０７の付勢力はバリヤ付勢ばね１０６の付勢力よりも強く設定されており、ズームレンズ鏡筒７１がズーム領域（図６）に繰り出されているときには、バリヤ駆動環付勢ばね１０７がバリヤ駆動環１０３をバリヤ開放用の角度位置に保持して、バリヤ付勢ばね１０６に抗してバリヤ羽根１０４、１０５が開かれる。そしてズームレンズ鏡筒７１がズーム領域から収納位置（図７）へ移動する途中で、カム環１１のバリヤ駆動環押圧面１１ｄ（図３、図１３）がバリヤ駆動環１０３をバリヤ開放方向と反対方向に強制回動させ、バリヤ駆動環１０３がバリヤ羽根１０４、１０５に対する係合を解除して、該バリヤ羽根１０４、１０５がバリヤ付勢ばね１０６の付勢力によって閉じられる。レンズバリヤ機構の前部は、バリヤカバー１０１（化粧板）によって覆われている。
【００４２】
以上の構造のズームレンズ鏡筒７１の全体的な繰出及び収納動作を、図６、図７及び図１９を参照して説明する。図１９は、ズームレンズ鏡筒７１の主要な部材の関係を概念的に示したものであり、各部材の符号の後の括弧内の「Ｓ」は固定部材、「Ｌ」は光軸方向の直線移動のみ行う部材、「Ｒ」は回転のみ行う部材、「ＲＬ」は回転しながら光軸方向に移動する部材であることをそれぞれ意味している。また、括弧内に二つの記号が併記されている部材は、繰出時及び収納時にその動作態様が切り換わることを意味している。
【００４３】
カム環１１が収納位置から定位置回転状態に繰り出される段階までは既に説明しているので簡潔に述べる。図７の鏡筒収納状態では、ズームレンズ鏡筒７１はカメラボディ７２内に完全に格納されており、カメラボディ７２の前面は、ズームレンズ鏡筒７１が突出しないフラット形状になっている。この鏡筒収納状態からズームモータ１５０によりズームギヤ２８を繰出方向に回転駆動させると、ヘリコイド環１８と第３外筒１５の結合体がヘリコイド（雄ヘリコイド１８ａ、雌ヘリコイド２２ａ）に従って回転繰出される。直進案内環１４は、第３外筒１５及びヘリコイド環１８と共に前方に直進移動する。このとき、第３外筒１５により回転力が付与されるカム環１１は、直進案内環１４の前方への直進移動分と、該直進案内環１４との間に設けたリード構造（カム環ローラ３２、リード溝部１４ｅ-３）による繰出分との合成移動を行う。ヘリコイド環１８とカム環１１が前方の所定位置まで繰り出されると、それぞれの回転繰出構造（ヘリコイド、リード）の機能が解除されて、鏡筒中心軸Ｚ０を中心とした周方向回転のみを行うようになる。
【００４４】
カム環１１が回転すると、その内側では、２群直進案内環１０を介して直進案内された２群レンズ移動枠８が、２群用カムフォロア８ｂと２群案内カム溝１１ａの関係によって光軸方向に所定の軌跡で移動される。図７の鏡筒収納状態では、２群レンズ移動枠８内の２群レンズ枠６は、ＣＣＤホルダ２１に突設したカム突起２１ａの作用によってＡＦレンズ枠５１の上側の収納用退避位置に保持されており、第２レンズ群ＬＧ２は撮影光軸Ｚ１から退避する。２群レンズ枠６は、２群レンズ移動枠８が収納位置からズーム領域まで繰り出される途中でカム突起２１ａから離れて、２群レンズ枠戻しばね３９の付勢力によって第２レンズ群ＬＧ２の光軸を撮影光軸Ｚ１と一致させる撮影用位置（図６）に回動する。以後、ズームレンズ鏡筒７１を再び収納位置に移動させるまでは、２群レンズ枠６は撮影用位置に保持される。
【００４５】
また、カム環１１が回転すると、該カム環１１の外側では、第２外筒１３を介して直進案内された第１外筒１２が、１群用ローラ３１と１群案内カム溝１１ｂの関係によって光軸方向に所定の軌跡で移動される。
【００４６】
すなわち、撮像面（ＣＣＤ受光面）に対する第１レンズ群ＬＧ１と第２レンズ群ＬＧ２の繰出位置はそれぞれ、前者が、固定環２２に対するカム環１１の前方移動量と、該カム環１１に対する第１外筒１２のカム繰出量との合算値として決まり、後者が、固定環２２に対するカム環１１の前方移動量と、該カム環１１に対する２群レンズ移動枠８のカム繰出量との合算値として決まる。ズーミングは、この第１レンズ群ＬＧ１と第２レンズ群ＬＧ２が互いの空気間隔を変化させながら撮影光軸Ｚ１上を移動することにより行われる。図７の収納位置から鏡筒繰出を行うと、まず図６の下半断面に示すワイド端の繰出状態になり、さらにズームモータ１５０を鏡筒繰出方向に駆動させると、同図の上半断面に示すテレ端の繰出状態となる。図６から分かるように、本実施形態のズームレンズ鏡筒７１は、ワイド端では第１レンズ群ＬＧ１と第２レンズ群ＬＧ２の間隔が大きく、テレ端では、第１レンズ群ＬＧ１と第２レンズ群ＬＧ２が互いの接近方向に移動して間隔が小さくなる。このような第１レンズ群ＬＧ１と第２レンズ群ＬＧ２の空気間隔の変化は、２群案内カム溝１１ａと１群案内カム溝１１ｂの軌跡によって与えられるものである。このテレ端とワイド端の間のズーム領域（ズーミング使用領域）では、カム環１１、第３外筒１５及びヘリコイド環１８は、前述の定位置回転のみを行い、光軸方向へは進退しない。
【００４７】
ズーム領域では、被写体距離に応じてＡＦモータ１６０を駆動することにより、第３レンズ群ＬＧ３（ＡＦレンズ枠５１）が撮影光軸Ｚ１に沿って移動してフォーカシングがなされる。
【００４８】
ズームモータ１５０を鏡筒収納方向に駆動させると、ズームレンズ鏡筒７１は、前述の繰り出し時とは逆の収納動作を行い、カメラボディ７２の内部に完全に格納される収納位置（図７）まで移動される。この収納位置への移動の途中で、２群レンズ枠６がカム突起２１ａによって収納用退避位置に回動され、２群レンズ移動枠８と共に後退する。ズームレンズ鏡筒７１が収納位置まで移動されると、第２レンズ群ＬＧ２は、光軸方向において第３レンズ群ＬＧ３やローパスフィルタＬＧ４と同位置に格納される（鏡筒の径方向に重なる）。この収納時の第２レンズ群ＬＧ２の退避構造によってズームレンズ鏡筒７１の収納長が短くなり、図７の左右方向におけるカメラボディ７２の厚みを小さくすることが可能となっている。
【００４９】
デジタルカメラ７０は、ズームレンズ鏡筒７１に連動するズームファインダを備えている。ズームファインダは、ファインダギヤ３０をスパーギヤ部１８ｃに噛合させてヘリコイド環１８から動力を得ており、該ヘリコイド環１８がズーム領域において前述の定位置回転を行うと、その回転力を受けてファインダギヤ３０が回転する。ファインダ光学系は、対物窓８１ａ、第１の可動変倍レンズ８１ｂ、第２の可動変倍レンズ８１ｃ、プリズム８１ｄ、接眼レンズ８１ｅ、接眼窓８１ｆを有し、第１と第２の可動変倍レンズ８１ｂ、８１ｃをファインダ対物系の光軸Ｚ３に沿って所定の軌跡で移動させることで変倍を行う。ファインダ対物系の光軸Ｚ３は、撮影光軸Ｚ１と平行である。可動変倍レンズ８１ｂ及び８１ｃの保持枠は、ガイドシャフト８２によって光軸Ｚ３方向に移動可能に直進案内され、かつガイドシャフト８２と平行なシャフトねじから駆動力を受けるようになっている。このシャフトねじとファインダギヤ３０の間に減速ギヤ列が設けられており、ファインダギヤ３０が回転するとシャフトねじが回転し、可動変倍レンズ８１ｂ、８１ｃが進退する。以上のズームファインダの構成要素は、図５に示すファインダユニット８０としてサブアッシされ、固定環２２の上部に取り付けられる。
【００５０】
［レンズ鏡筒収納構造の説明］
続いて、第２レンズ群ＬＧ２の退避構造を含めたズームレンズ鏡筒７１の収納構造の詳細を説明する。なお、以下の説明における上下（縦）方向及び左右（横）方向とは、図２８や図２９のようにカメラの正面または背面から見た上下方向及び左右方向に対応するものとする。また、前後方向とは光軸と平行な方向である。また、部材を識別しやすくするために、一部の図面では部材毎に外形線の太さを異ならせたり、線種を異ならせている。
【００５１】
第２レンズ群ＬＧ２は、図２０に示す各部材によって２群レンズ移動枠８に支持されている。２群レンズ枠６は、第２レンズ群ＬＧ２を支持するレンズ筒６ａ、該レンズ筒６ａの径方向に延びる揺動アーム６ｃ、この揺動アーム６ｃの先端に設けた揺動中心筒６ｂ、及びレンズ筒６ａから揺動アーム６ｃとは異なる径方向へ延出されたストッパアーム６ｅを有している。揺動中心筒６ｂには、第２レンズ群ＬＧ２の光軸と平行な方向に貫通する揺動軸孔６ｄが形成されている。揺動中心筒６ｂには、揺動アーム６ｃとの接続部を挟んだ光軸方向の前後位置に、それぞれ円筒状の外周面を有する前方ばね支持部６ｆと後方ばね支持部６ｇが形成されており、前方ばね支持部６ｆの前端部付近と後方ばね支持部６ｇの後端部付近の外周面には、ばね抜止突起６ｈ、６ｉが突設されている。揺動中心筒６ｂからは揺動アーム６ｃと異なる方向に向けて退避作用アーム６ｊが延出されており、該退避作用アーム６ｊにはばね掛け孔６ｋが形成されている。また、揺動アーム６ｃにはばね掛け孔６ｐが形成されている。ばね掛け孔６ｋやばね掛け孔６ｐは、図３５ないし図３７に表れている。
【００５２】
揺動アーム６ｃからは光軸後方へ向けて後方突出部６ｍが突設され、該後方突出部６ｍの先端部には第２レンズ群ＬＧ２の光軸と直交する平面状のＡＦ枠当接面６ｎが形成されている。図４５や図４６に示すように、レンズ筒６ａの後端部には第２レンズ群ＬＧ２を抜け止めるための２群レンズ保持蓋９が固定されているが、ＡＦ枠当接面６ｎは、該２群レンズ保持蓋９よりも光軸方向後方に位置している。すなわち、ＡＦ枠当接面６ｎは、光軸方向において第２レンズ群ＬＧ２の最後部よりも後方に位置している。
【００５３】
２群レンズ枠支持板３６は、上下方向に長く左右方向に幅狭の細長の板状部材であり、その長手方向に向けて上から順に、第１縦長孔（第１の長孔）３６ａ、回動軸嵌合孔３６ｂ、カム突起挿脱開口３６ｃ、ビス螺合孔（支持板固定手段）３６ｄ、横長孔（第２の長孔）３６ｅ及び第２縦長孔（移動ガイド手段、第３の長孔）３６ｆが形成されている。これらの孔部はいずれも２群レンズ枠支持板３６の表裏を貫通する貫通孔である。２群レンズ枠支持板３６の外周部には、凹状のばね掛け部３６ｇが形成されている。
【００５４】
２群レンズ枠支持板３７は、２群レンズ枠支持板３６と略同形状の細長の板状部材であり、その長手方向に向けて上から順に、第１縦長孔（第１の長孔）３７ａ、回動軸嵌合孔３７ｂ、カム突起挿脱開口３７ｃ、ビス螺合孔（支持板固定手段）３７ｄ、横長孔（第２の長孔）３７ｅ及び第２縦長孔（移動ガイド手段、第３の長孔）３７ｆが形成されている。これらの孔部はいずれも２群レンズ枠支持板３７の表裏を貫通する貫通孔である。カム突起挿脱開口３７ｃにはさらに、その内縁部の一部を切り欠いてガイドキー進入溝３７ｇが形成されている。
【００５５】
前後の２群レンズ枠支持板３６、３７に設けたビス螺合孔３６ｄ、３７ｄは同口径のビス孔であり、支持板固定ビス６６のビス軸部６６ａが螺合可能である。ビス軸部６６ａの一端部には、ドライバ（調整具）が係合するためのドライバ係合凹部（回転操作部）６６ｂを有する。
【００５６】
第１偏心軸部材（第１の偏心軸部材）３４Ｘは、大径軸部３４Ｘ-ａを挟んだ前後端部に一対の前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃを有している。前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃは、大径軸部３４Ｘ-ａの中心軸に対して偏心させて同軸かつ同径に形成されている。前方偏心ピン３４Ｘ-ｂの端部には、ドライバ（調整具）を係合させるためのドライバ係合凹部（回転操作部）３４Ｘ-ｄが形成されている。第２偏心軸部材（第２の偏心軸部材）３４Ｙも第１偏心軸部材３４Ｘと同様の構造である。すなわち、大径軸部３４Ｙ-ａを挟んだ前後端部に一対の前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃを有し、前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃは、大径軸部３４Ｙ-ａの中心軸に対して偏心させて同軸かつ同径に形成されている。前方偏心ピン３４Ｙ-ｂの端部には、ドライバ（調整具）を係合させるためのドライバ係合凹部（回転操作部）３４Ｙ-ｄが形成されている。
【００５７】
２群レンズ枠６の後方ばね支持部６ｇの内部には、揺動軸孔６ｄに連通し該後方ばね支持部６ｇよりも内径が大きいばね収納孔（不図示）が形成されており、該ばね収納孔内に軸方向押圧ばね３８を収納することができる。軸方向押圧ばね３８は圧縮コイルばねからなる。また、２群レンズ枠戻しばね３９と回転伝達ばね４０はそれぞれトーションばねであり、２群レンズ枠戻しばね３９は、２群レンズ枠６の前方ばね支持部６ｆの外周面に装着可能で、回転伝達ばね４０は後方ばね支持部６ｇの外周面に装着可能となっている。２群レンズ枠戻しばね３９は、前後方向に延出された前方ばね端部３９ａと後方ばね端部３９ｂとを有し、回転伝達ばね４０は、径方向へ突出された固定ばね端部４０ａと可動ばね端部４０ｂとを有する。
【００５８】
２群回動軸３３は、２群レンズ枠６の揺動軸孔６ｄに対して相対回転可能かつ径方向にガタなく嵌まる径を有し、その両端部の外径サイズは２群レンズ枠支持板３６の回動軸嵌合孔３６ｂと２群レンズ枠支持板３７の回動軸嵌合孔３７ｂの内径サイズに対応している。揺動軸孔６ｄに挿入された２群回動軸３３の軸線は、第２レンズ群ＬＧ２の光軸と平行になる。２群回動軸３３はまた、光軸方向後方側の端部近傍にフランジ３３ａを有し、該フランジ３３ａは後方ばね支持部６ｇのばね収納孔（不図示）内に進入して軸方向押圧ばね３８に当接することができる。
【００５９】
図２４及び図２５に単体形状を示す２群レンズ移動枠８の内部は光軸方向に貫通する貫通空間８ｎとなっており、該貫通空間８ｎの光軸方向における略中央に位置する中間フランジ部８ｓには、上下方向に長い縦長形状をなす２群レンズ移動開口８ｔが形成されている。シャッタユニット７６は、中間フランジ部８ｓの前面側に固定される。また、中間フランジ部８ｓの後方の内周面には、レンズ筒６ａの外縁部形状に対応するレンズ筒進入凹部８ｑと、ストッパアーム６ｅの外縁部形状に対応するストッパアーム進入凹部８ｒが形成されている（図２９参照）。
【００６０】
図２４及び図２５に示すように、２群レンズ移動枠８を正面から見て２群レンズ移動開口８ｔの右側には、該２群レンズ移動開口８ｔとは重ならないようにして、光軸と直交する平面状の前方支持板装着面（支持板固定手段）８ｃが形成されている。前方支持板装着面８ｃは図２４及び図２５にハッチングを付した領域であり、中間フランジ部８ｓ及び該中間フランジ部８ｓの前面に取り付けたシャッタユニット７６よりも前方に位置している。前方支持板装着面８ｃは２群レンズ移動枠８の前方に露出する面であるが、該２群レンズ移動枠８には、前方支持板装着面８ｃよりも前方に突出する３箇所の部分円筒状部８ｄが形成されており、各部分円筒状部８ｄの外周面には前方カムフォロア８ｂ-１が設けられている。一方、２中間フランジ部８ｓを挟んだ前方支持板装着面８ｃの後方には、該前方支持板装着面８ｃと平行な平面状の後方支持板装着面（支持板固定手段）８ｅが形成されており、後方支持板装着面８ｅは２群レンズ移動枠８の後端面と面一になっている。
【００６１】
２群レンズ移動枠８には、上側から順に、偏心軸支持孔８ｆ、揺動中心筒収納孔８ｇ、ビス挿通孔８ｈ、偏心軸支持孔８ｉが形成されており、これらの各孔は、それぞれが光軸方向に向けて前方支持板装着面８ｃと後方支持板装着面８ｅを貫通している。揺動中心筒収納孔８ｇの内壁面にはさらに、光軸と平行なキー溝８ｐが形成されており、このキー溝８ｐも前方支持板装着面８ｃと後方支持板装着面８ｅを貫通している。上側の偏心軸支持孔８ｆは、第１偏心軸部材３４Ｘの大径軸部３４Ｘ-ａを回転可能に支持する内径サイズに形成されており、下側の偏心軸支持孔８ｉは、第２偏心軸部材３４Ｙの大径軸部３４Ｙ-ａを回転可能に支持する内径サイズに形成されている（図３１参照）。一方、ビス挿通孔８ｈの内径サイズは、支持板固定ビス６６のビス軸部６６ａとの間に相当の隙間ができるように大きく形成されている（図３１参照）。また、前方支持板装着面８ｃと後方支持板装着面８ｅには、互いに同心で同径の円筒状をなす前方ボス（移動ガイド手段、固定突起、突起）８ｊと後方ボス（移動ガイド手段、固定突起、突起）８ｋが突設されている。２群レンズ移動枠８にはさらに、２群レンズ移動開口８ｔの下方位置に、中間フランジ部８ｓを前後方向へ貫通する回動規制ピン挿通孔８ｍが形成されている。
【００６２】
回動規制ピン３５は、回動規制ピン挿通孔８ｍに対して回転可能に挿入される大径軸部３５ａの一端部に、該大径軸部３５ａに対して偏心する偏心ピン３５ｂを有し、他端部にドライバ（調整具）を係合させるためのドライバ係合凹部（回転操作部）３５ｃを有している。
【００６３】
以上の各要素を組み合わせた状態が、図２６ないし図２９である。組み立ては次のように行う。まず、２群レンズ枠戻しばね３９と回転伝達ばね４０を２群レンズ枠６に対して装着する。２群レンズ枠戻しばね３９は、コイル状部を揺動中心筒６ｂの前方ばね支持部６ｆの外周面に取り付け、後方ばね端部３９ｂを揺動中心筒６ｂと揺動アーム６ｃの境界部付近に係合させる（図２２）。２群レンズ枠戻しばね３９の前方ばね端部３９ａは、２群レンズ枠６に対しては係合させない。回転伝達ばね４０は、コイル状部を揺動中心筒６ｂの後方ばね支持部６ｇの外周面に取り付け、一方の固定ばね端部４０ａを揺動アーム６ｃのばね掛け孔６ｐに挿入させ、他方の可動ばね端部４０ｂを退避作用アーム６ｊのばね掛け孔６ｋに挿入させる。固定ばね端部４０ａはばね掛け孔６ｐに固定され、可動ばね端部４０ｂは、ばね掛け孔６ｋ内で固定ばね端部４０ａに対して接離する方向へ図３７に示すθ１の移動が許される。外力を加えない状態では、回転伝達ばね４０は、該固定ばね端部４０ａ及び４０ｂを接近させる方向に若干撓んだ状態で２群レンズ枠６に支持され、その撓みに対する復元力によって可動ばね端部４０ｂは、ばね掛け孔６ｋ内の一方の壁面に当て付いた状態になる（図３７）。２群レンズ枠戻しばね３９と回転伝達ばね４０は、前後のばね抜止突起６ｈ、６ｉによって光軸方向へ抜け止められる。
【００６４】
２群レンズ枠戻しばね３９と回転伝達ばね４０の取り付けとは別に、軸方向押圧ばね３８を後方ばね支持部６ｇ内のばね収納孔（不図示）に挿入した上で、２群回動軸３３を揺動軸孔６ｄに挿入する。２群回動軸３３のフランジ３３ａは後方ばね支持部６ｇ内に進入して軸方向押圧ばね３８に当接する。２群回動軸３３の軸長は揺動中心筒６ｂの軸長よりも長く、２群回動軸３３の両端部は揺動中心筒６ｂから前後に突出する。
【００６５】
揺動中心筒６ｂに対する上記各部材の取り付けと並行して、第１偏心軸部材３４Ｘと第２偏心軸部材３４Ｙをそれぞれ、２群レンズ移動枠８の偏心軸支持孔８ｆと偏心軸支持孔８ｉに挿入しておく。第１偏心軸部材３４Ｘと第２偏心軸部材３４Ｙはそれぞれ、大径軸部３４Ｘ-ａと大径軸部３４Ｙ-ａの前端側の一部領域が他の領域よりも大径になっており、偏心軸支持孔８ｆと偏心軸支持孔８ｉもこれに対応して、光軸方向前方の一部領域の内径サイズが他の領域の内径サイズよりも大きくなっている（図３１参照）。したがって、第１偏心軸部材３４Ｘと第２偏心軸部材３４Ｙをそれぞれ、偏心軸支持孔８ｆと偏心軸支持孔８ｉに対して光軸方向前方から挿入していくと、偏心軸支持孔８ｆ、８ｉの内径サイズの段差部分に大径軸部３４Ｘ-ａ、３４Ｙ-ａの大径部分が当接した時点（図３１の位置）で挿入が規制される。この状態では、前方支持板装着面８ｃから前方偏心ピン３４Ｘ-ｂと前方偏心ピン３４Ｙ-ｂが突出し、後方支持板装着面８ｅから後方偏心ピン３４Ｘ-ｃと後方偏心ピン３４Ｙ-ｃが突出する。
【００６６】
続いて、揺動中心筒６ｂから突出する２群回動軸３３の前端部を回動軸嵌合孔３６ｂに挿入し、後端部を回動軸嵌合孔３７ｂに挿入させつつ、前方支持板装着面８ｃと後方支持板装着面８ｅを前後から挟み込むようにして２群レンズ枠支持板３６と２群レンズ枠支持板３７を２群レンズ移動枠８に取り付ける。このとき、前方の２群レンズ枠支持板３６の第１縦長孔３６ａ、横長孔３６ｅ及び第２縦長孔３６ｆに対して、前方支持板装着面８ｃから突出する３つの前方偏心ピン３４Ｘ-ｂ、前方偏心ピン３４Ｙ-ｂ及び前方ボス８ｊをそれぞれ係合させる。また、後方の２群レンズ枠支持板３７の第１縦長孔３７ａ、横長孔３７ｅ及び第２縦長孔３７ｆに対して、後方支持板装着面８ｅから突出する３つの後方偏心ピン３４Ｘ-ｃ、後方偏心ピン３４Ｙ-ｃ及び後方ボス８ｋをそれぞれ係合させる。各偏心ピンやボスは、対応する長孔に対して、その長手方向には摺動可能で幅方向には移動不能に嵌まる。
【００６７】
最後に、前後のビス螺合孔３６ｄ、３７ｄに対して支持板固定ビス６６を螺合させ、２群レンズ枠支持板３６、３７を共締めする。支持板固定ビス６６は、先に前方のビス螺合孔３６ｄに螺合され、ビス挿通孔８ｈを通してから後方のビス螺合孔３７ｄに螺合される。両方のビス螺合孔３６ｄ、３７ｄに螺合した状態で支持板固定ビス６６を締め付けていくと、２群レンズ枠支持板３６が前方支持板装着面８ｃに押し付けられ、２群レンズ枠支持板３７が後方支持板装着面８ｅに押し付けられ、２群レンズ枠支持板３６と２群レンズ枠支持板３７は、前方支持板装着面８ｃと後方支持板装着面８ｅの光軸方向間隔分だけ離間した状態で２群レンズ移動枠８に固定される。その結果、第１偏心軸部材３４Ｘと第２偏心軸部材３４Ｙが、２群レンズ枠支持板３６と２群レンズ枠支持板３７によって光軸方向に抜け止められる。２群回動軸３３は、フランジ３３ａを２群レンズ枠支持板３７に当接させることで後方へ移動規制され、圧縮状態にある軸方向押圧ばね３８を介して揺動中心筒６ｂを前方に押圧するため、該揺動中心筒６ｂの前端部が２群レンズ枠支持板３６に押し付けられる。これにより、２群レンズ移動枠８に対する２群レンズ枠６の光軸方向位置が一定に保たれる。また、２群レンズ枠支持板３７を２群レンズ移動枠８に固定すると、ガイドキー進入溝３７ｇとキー溝８ｐとが光軸方向に連通される（図３０参照）。
【００６８】
２群レンズ枠支持板３６を固定したら、２群レンズ枠戻しばね３９の前方ばね端部３９ａをばね掛け部３６ｇに係合させる。後方ばね端部３９ｂは既に揺動アーム６ｃに係合しており、前方ばね端部３９ａとばね掛け部３６ｇを係合させることにより２群レンズ枠戻しばね３９が撓み、２群レンズ枠６に対して光軸方向前方から見て（図３２）、２群回動軸３３を中心とする反時計方向への回転付勢力が作用する。
【００６９】
２群レンズ枠６の取り付けとは別に、回動規制ピン３５を２群レンズ移動枠８の回動規制ピン挿通孔８ｍに挿入する。回動規制ピン挿通孔８ｍは、図２６及び図２７に示す位置まで回動規制ピン３５を挿入すると、それ以上の挿入を規制するような内面形状となっており、この挿入規制状態において、図２７に示すように偏心ピン３５ｂが回動規制ピン挿通孔８ｍから後方へ突出する。
【００７０】
以上のようにして２群レンズ枠６を２群レンズ移動枠８に取り付けた状態では、２群レンズ枠６は２群回動軸３３を中心として回動（揺動）することができる。２群レンズ移動枠８の揺動中心筒収納孔８ｇは、２群レンズ枠６が揺動しても揺動中心筒６ｂや揺動アーム６ｃと干渉しないように、十分に広く形成されている。２群回動軸３３は光軸と平行な軸であるから、２群レンズ枠６の回動に伴って第２レンズ群ＬＧ２は、その光軸を撮影光軸Ｚ１と平行とした状態を維持しつつ平行移動される。２群レンズ枠６は、ストッパアーム６ｅの先端部が偏心ピン３５ｂに当接することによって一方の回動端（揺動端）が決められる。２群レンズ枠戻しばね３９は、ストッパアーム６ｅを偏心ピン３５ｂに当接させる方向に２群レンズ枠６を付勢している。
【００７１】
２群レンズ移動枠８にはさらに、シャッタユニット７６が取り付けられて。図２６ないし図２９の状態にサブアッシされる。図２６や図２８から分かるように、シャッタユニット７６は中間フランジ部８ｓの前面側に固定される。前方支持板装着面８ｃは、この固定状態におけるシャッタユニット７６内のシャッタＳ及び絞りＡよりも、光軸方向において前方に位置するようになっている。２群レンズ枠６のレンズ筒６ａは、その前端部側の一部領域が２群レンズ移動開口８ｔ内に位置しており、該２群レンズ枠６の角度位置に関わらずシャッタユニット７６の直後に位置するようになっている。
【００７２】
２群レンズ移動枠８には、周方向に位置を異ならせて直進案内溝８ａが３つ形成されているが、そのうちひとつの直進案内溝８ａ-Ｗは、残る２つの直進案内溝８ａよりも幅広で、かつ底部が径方向に貫通しており、該直進案内溝８ａ-Ｗを通して、シャッタユニット７６から延出される露出制御ＦＰＣ基板７７を２群レンズ移動枠８の外側に導くことが可能になっている。これに対応して、２群直進案内環１０に設けた３つの直進案内キー１０ｃのうちひとつは、直進案内溝８ａ-Ｗの幅に対応する幅広の直進案内キー１０ｃ-Ｗとなっており、該直進案内キー１０ｃ-Ｗには、リング部１０ｂとの接続部分の近傍を一部切り欠いて、径方向へ貫通するＦＰＣ通し孔１０ｄ（図１５）が形成されている。
【００７３】
２群レンズ移動枠８と２群直進案内環１０を組み合わせた状態では、露出制御ＦＰＣ基板７７は図４２のように配設される。まずシャッタユニット７６から第１直線状部７７ａが光軸方向後方へ向けて延出され、続いて２群レンズ移動枠８の後端部付近でＵ字状部（ループ状部）７７ｂが形成されて前方へ湾曲され、第２直線状部７７ｃが直進案内キー１０ｃ-Ｗの内周面に沿って前方へ向かい、直進案内キー１０ｃ-Ｗの先端部で外側に折り返され、該直進案内キー１０ｃ-Ｗの外周面に沿って再度後方へ延出される第３直線状部７７ｄとなる。第３直線状部７７ｄの先は、ＦＰＣ通し孔１０ｄを通して２群レンズ移動枠８の後方へ延出されてから制御回路１４０に接続される。露出制御ＦＰＣ基板７７は、第３直線状部７７ｄの一部が直進案内キー１０ｃ-Ｗの外周面に両面テープなどを用いて固定されており、２群レンズ移動枠８と２群直進案内環１０の相対移動に応じてＵ字状部７７ｃの大きさを変化させることができる。
【００７４】
以上のようにサブアッシされた２群レンズ移動枠８は、カム環１１を介して光軸方向への移動が与えられ、該２群レンズ移動枠８の後方には、カム環１１の動きとは独立して光軸方向へ進退可能にＡＦレンズ枠５１が支持され、さらに該ＡＦレンズ枠５１の後方にはＣＣＤホルダ２１が固定されている。
【００７５】
ＡＦレンズ枠５１は遮光性材料からなり、図３８ないし図４１、及び図４４ないし図４７に示すように、ガイド孔５１ａ及び５１ｂを有する一対の腕部５１ｄ及び５１ｅと、該腕部５１ｄ及び５１ｅよりも前方に突出する前方突出筒状部５１ｃとを有している。前方突出筒状部５１ｃは、撮影光軸Ｚ１に垂直で略正方形をなす先端面（底面）５１ｃ１と、先端面５１ｃ１の各辺から撮影光軸Ｚ１に平行にＣＣＤ６０側に延びる４つの側面５１ｃ３、５１ｃ４、５１ｃ５及び５１ｃ６を有する箱状（角筒状）をなしており、先端面５１ｃ１と反対側の後端部はローパスフィルタＬＧ４及びＣＣＤ６０側に向けて開放されている。前方突出筒状部５１ｃの先端面５１ｃ１には、中心が撮影光軸Ｚ１と一致する円形の開口部５１ｃ２が設けられ、該開口部５１ｃ２の内側に第３レンズ群ＬＧ３を支持している。腕部５１ｄ及び５１ｅは、前方突出筒状部５１ｃを正面から見て左上部分及び右下部分、すなわち側面５１ｃ３及び５１ｃ６の交線付近、並びに、側面５１ｃ４及び５１ｃ５の交線付近から、撮影光軸Ｚ１を中心とする放射方向（径方向）に向かって延設されている（図４７参照）。図４５及び図４６から分かるように、腕部５１ｄ及び５１ｅは、側面５１ｃ３及び５１ｃ６、並びに、側面５１ｃ４及び５１ｃ５の光軸方向の最後方部分に設けられている。
【００７６】
ＡＦレンズ枠５１の腕部５１ｄ及び５１ｅは、図６に示すようにそれぞれの先端部が固定環２２の環状部２２ｆの外側に突出しており、この突出する先端部に、光軸と平行なガイド孔５１ａ及び５１ｂが形成されている。これに対応して、ガイド孔５１ａに係合してＡＦレンズ枠５１の主案内をするＡＦガイド軸５２と、ガイド孔５１ｂに係合してＡＦレンズ枠５１副案内をするＡＦガイド軸５３とはそれぞれ、固定環２２の環状部２２ｆの外側に位置している。環状部２２ｆには、ＡＦレンズ枠５１が光軸方向に移動するときに腕部５１ｄ及び５１ｅとの干渉を避けるため、ＡＦガイド軸５２及び５３に沿って光軸方向への切欠２２ｇ及び２２ｈ（図８）が形成されている。また、図３９及び図４７に示すように、ガイド孔５１ａとガイド孔５１ｂは撮影光軸Ｚ１に関して対向する位置に形成されており、これに対応してＡＦガイド軸５２及び５３も、撮影光軸Ｚ１に関して対向する位置関係で設けられている。
【００７７】
ＡＦレンズ枠５１は、ＣＣＤホルダ２１の移動規制面２１ｂ（図６）に腕部５１ｄ及び５１ｅが当て付くまで光軸方向後方に移動可能であり、ＡＦレンズ枠５１が該後方移動端まで移動すると、ＣＣＤホルダ２１から光軸方向前方に向けて突設したカム突起２１ａの先端部がＡＦレンズ枠５１よりも前方に突出する（図３８、図４０及び図４１参照）。カム突起２１ａの光軸方向の延長上には、２群レンズ枠支持板３７のカム突起挿脱開口３７ｃと２群レンズ枠支持板３６のカム突起挿脱開口３６ｃが位置する。
【００７８】
図２１及び図２２に示すように、カム突起２１ａの先端部には光軸に対して傾斜する退避カム面２１ｃが形成され、該退避カム面２１ｃに連続する一方の側面には、光軸と平行な退避位置保持面２１ｄが形成されている。正面から見た図３５ないし図３７から分かるように、カム突起２１ａは、概ね撮影光軸Ｚ１を中心とする放射方向へ幅広に形成されており、退避カム面２１ｃは、該カム突起２１ａの幅方向を鏡筒内径側（撮影光軸Ｚ１に近い側）から鏡筒外径側（撮影光軸Ｚ１から遠い側）へ進むにつれて徐々に光軸方向前方への突出量を大きくする傾斜面として形成されている。図３５ないし図３７では、退避カム面２１ｃを判別しやすくするためにハッチングを付している。また、カム突起２１ａは、２群レンズ枠６の揺動中心筒６ｂとの干渉を避けるように、下面側が凸面で上面側が凹面となるように若干湾曲した断面形状を有しており、その下面側には、光軸と平行なガイドキー２１ｅが突設されている。ガイドキー２１ｅは、カム突起２１ａの基部からの一定範囲にのみ形成されており、カム突起２１ａの先端付近には形成されていない。ガイドキー２１ｅはガイドキー進入溝３７ｇに係合可能な断面形状となっている。
【００７９】
上記構造により支持された第２レンズ群ＬＧ２や第３レンズ群ＬＧ３は、次のような態様で動作する。前述の通り、ＣＣＤホルダ２１に対する２群レンズ移動枠８の光軸方向位置は、カム環１１の２群案内カム溝１１ａ（前方カム溝１１ａ-１と後方カム溝１１ａ-２）の軌跡による前後移動と、該カム環１１自身の前後移動とを合成して決定される。端的に言えば、２群レンズ移動枠８は、図６の上半に示すワイド端付近で最もＣＣＤホルダ２１から離間し、図７の鏡筒収納状態で最も接近する。このワイド端から収納位置までの２群レンズ移動枠８の後退動作を利用して、該２群レンズ移動枠８内で２群レンズ枠６を外径方向に退避させる。
【００８０】
ワイド端からテレ端までのズーム領域では、２群レンズ枠戻しばね３９の付勢力でストッパアーム６ｅを回動規制ピン３５に当接させることによって２群レンズ枠６の位置が一定に保たれており、このとき第２レンズ群ＬＧ２の光軸は、図６のように撮影光軸Ｚ１と一致している。図２９に示すように、この２群レンズ枠６の撮影用位置では、退避作用アーム６ｊの一部と回転伝達ばね４０の可動ばね端部４０ｂがカム突起挿脱開口３７ｃに臨んでいる。
【００８１】
撮影状態からカメラのメインスイッチをオフすると、制御回路１４０がＡＦモータ１６０を駆動させ、ＡＦレンズ枠５１は後退されてＣＣＤホルダ２１に接近し、図３８、図４０及び図４１に示す後方移動端に収納される。ＡＦレンズ枠５１の前方突出筒状部５１ｃは、先端面５１ｃ１側に第３レンズ群ＬＧ３を支持し、該第３レンズ群ＬＧ３の後方は側面５１ｃ３、５１ｃ４、５１ｃ５及び５１ｃ６に囲まれる開放空間となっているため、ＡＦレンズ枠５１が図７の後方移動端に移動すると、ＣＣＤホルダ２１の前面から突出して支持されたローパスフィルタＬＧ４及びＣＣＤ６０が、前方突出筒状部５１ｃの内部に進入して第３レンズ群ＬＧ３との間隔が狭まる。また、ＡＦレンズ枠５１が後方移動端に達すると、カム突起２１ａの先端部がＡＦレンズ枠５１よりも前方に突出した状態となる。
【００８２】
続いて、制御回路１４０はズームモータ１５０を収納方向に駆動させ、前述した鏡筒収納動作が行われる。ワイド端を超えてズームモータ１５０を収納方向に駆動すると、ローラ案内貫通溝１４ｅとカム環ローラ３２の関係によって、カム環１１が回転しながら光軸方向後方へ移動する。図１４に示す２群案内カム溝１１ａと２群用カムフォロア８ｂの関係から分かるように、２群レンズ移動枠８はカム環１１に対しては、ワイド端よりも収納状態の方が光軸方向において前方に位置するが、カム環１１内での２群レンズ移動枠８の当該前進移動量よりも固定環２２に対するカム環１１の後退移動量の方が大きいため、収納動作時には２群レンズ移動枠８は総体としてＣＣＤホルダ２１に接近する。
【００８３】
２群レンズ移動枠８が２群レンズ枠６と共に後退を続けると、やがてカム突起２１ａの先端部がカム突起挿脱開口３７ｃ内に入り込む（図２３）。前述の通り、撮影状態ではカム突起挿脱開口３７ｃに対して退避作用アーム６ｊの一部と回転伝達ばね４０の可動ばね端部４０ｂが臨んでおり、このときの退避作用アーム６ｊ、可動ばね端部４０ｂ及びカム突起２１ａの正面から見た位置関係は、図３５のようになっている。撮影光軸Ｚ１を中心とする放射方向において、可動ばね端部４０ｂの方が退避作用アーム６ｊ（ばね掛け孔６ｋ形成用の突出部は除く）よりもカム突起２１ａ側に突出している。一方、退避カム面２１ｃは撮影光軸Ｚ１から離間するほど前方への突出量を大きくする斜面である。換言すれば、退避カム面２１ｃは、図３５の右方へ進むほど紙面手前側への突出量を大きくする斜面であり、退避カム面２１ｃのうち最も前方に突出する領域は、可動ばね端部４０ｂの背後に位置している。よって、図３５の位置関係を保ちつつ２群レンズ枠６が２群レンズ移動枠８と共にＣＣＤホルダ２１側へ後退すると、退避カム面２１ｃは、退避作用アーム６ｊではなく可動ばね端部４０ｂに当接する。図４０は、可動ばね端部４０ｂが退避カム面２１ｃに当接する直前の２群レンズ枠６の位置を表している。
【００８４】
可動ばね端部４０ｂと退避カム面２１ｃが当接した状態で２群レンズ枠６が後退すると、退避カム面２１ｃの形状に従って可動ばね端部４０ｂを図３５の時計方向へ押圧する分力が生じ、回転伝達ばね４０の他端側の固定ばね端部４０ａを介して２群レンズ枠６に該時計方向への回動力が伝達される。回転伝達ばね４０のばね力（硬さ）は、通常の鏡筒収納動作で２群レンズ枠６自体に作用する回転抵抗によっては図３５に示す状態以上に撓まされることなく、２群レンズ枠６へ回転力を伝達するように設定されている。すなわち、回転伝達ばね４０の弾性復元力は、２群レンズ枠戻しばね３９が２群レンズ枠６を撮影用位置に保持する付勢力よりも強く設定されている。
【００８５】
退避カム面２１ｃによる回転押圧力を受けた２群レンズ枠６は、２群レンズ移動枠８の後退動作に伴い、図２９に示す撮影用位置から図３０に示す退避位置へ向けて、２群レンズ枠戻しばね３９の付勢力に抗して２群回動軸３３を中心として回動する。これに伴い可動ばね端部４０ｂは、図３５の位置から図３６の位置へ向けて退避カム面２１ｃ上を移動する。２群レンズ枠６が図３０の退避位置まで回動すると、図３７のように可動ばね端部４０ｂが退避カム面２１ｃを乗り越えて退避位置保持面２１ｄに係合し、以降は２群レンズ移動枠８が後退動作を行っても２群レンズ枠６に退避方向の回動力が与えられなくなる。退避位置に保持された２群レンズ枠６は、レンズ筒６ａの外縁部がレンズ筒進入凹部８ｑ内に進入し、ストッパアーム６ｅの外縁部がストッパアーム進入凹部８ｒ内に進入している。
【００８６】
２群レンズ移動枠８は、２群レンズ枠６が退避位置に達した後も、図７の収納位置に達するまで引き続き後退する。２群レンズ枠６は、可動ばね端部４０ｂが退避位置保持面２１ｄに係合した状態で退避位置に保たれつつ、２群レンズ移動枠８と共に図４１の位置まで後退する。このときカム突起２１ａの先端部は、揺動中心筒収納孔８ｇを貫通して、カム突起挿脱開口３６ｃから前方に突出する。
【００８７】
図７及び図４１に示すように、収納状態では、レンズ筒６ａがＡＦレンズ枠５１の前方突出筒状部５１ｃの外側（上側）のスペースに移動しており、該前方突出筒状部５１ｃは、撮影時には第２レンズ群ＬＧ２が位置していた２群レンズ移動枠８内の空間に入り込み、第３レンズ群ＬＧ３がシャッタユニット７６の直後に位置される。また、図６と図７の比較から分かる通り、ＡＦレンズ枠５１が後方移動端に移動したことにより、ローパスフィルタＬＧ４とＣＣＤ６０は、前方突出筒状部５１ｃ内に収納（進入）されて第３レンズ群ＬＧ３に対する光軸方向の相対間隔が撮影状態に比べて小さくなっている。つまり、第２レンズ群ＬＧ２が、第３レンズ群ＬＧ３、ローパスフィルタＬＧ４及びＣＣＤ６０に対して光軸方向位置を重複させた（径方向に並んだ）状態となる。撮影光学系を構成するレンズ群などの光学要素を光軸方向にのみ移動させる従来のタイプのレンズ鏡筒では、複数の光学要素の厚みの合計値以上には鏡筒収納長を短縮化することができなかったが、本実施形態の構造によれば、光軸方向における第２レンズ群ＬＧ２の収納スペースを実質的に省略することができ、鏡筒収納長を短くすることが可能になっている。
【００８８】
本実施形態では、以上のようなスペース効率に優れた収納状態を得るため、特にＡＦレンズ枠５１の形状とその支持構造を工夫している。すなわち、第２レンズ群ＬＧ２を図７の位置まで後退させるために、ＡＦレンズ枠５１のガイド機構であるＡＦガイド軸５２及び５３を固定環２２の環状部２２ｆの外側に配置すると共に、該ＡＦガイド軸５２及び５３の案内を受けるＡＦレンズ枠５１の腕部５１ｄ及び５１ｅを、前方突出筒状部５１ｃの光軸方向の後端部から延出させている。まず、ＡＦガイド軸５２及び５３を固定環２２の環状部２２ｆより外側に配置することで、該ＡＦガイド軸５２及び５３と干渉するおそれなく、２群レンズ枠６や２群レンズ移動枠８、さらにはこれらを光軸方向に移動させるための回転環であるカム環１１やヘリコイド環１８の移動スペースを、固定環２２の内側に得ることができた。見方を変えると、固定環２２内部に位置する２群レンズ枠６などの移動部材による制限を受けずにＡＦガイド軸５２及び５３を配設できるので、ＡＦガイド枠５１に対するＡＦガイド軸５２及び５３の案内長を十分長く取って、高いガイド精度を得ることが可能になった。また、前方突出筒状部５１ｃの先端部や中間部分でなく後端部に腕部５１ｄ及び５１ｅを設けることで、該前方突出筒状部５１ｃの外側と腕部５１ｄ及び５１ｅの前方とによって形成されるスペースが広くなっている。これにより、腕部５１ｄ及び５１ｅに制限されることなく、レンズ筒６ａの略全体と前方突出筒状部５１ｃの光軸方向位置が重複する深い位置まで、２群レンズ枠６を後退（沈胴）することが可能になった。
【００８９】
さらに、ＡＦレンズ枠５１において前方突出筒状部５１ｃの先端部に第３レンズ群ＬＧ３を支持し、収納状態では、該第３レンズ群ＬＧ３の後方にローパスフィルタＬＧ４及びＣＣＤ６０を収納するようにしたので、より一層スペース効率に優れた収納状態を得ることができる。
【００９０】
以上に加えてワイド端からの収納動作ではさらに、２群レンズ移動枠８のみならず、第１レンズ群ＬＧ１を支持する第１外筒１２もカム環１１と共に後退しており、図７の収納状態では、シャッタユニット７６を挟んで第１レンズ群ＬＧ１と第３レンズ群ＬＧ３の光軸方向の相対間隔も小さくなっている。つまり、本実施形態のズームレンズ鏡筒７１では、撮影光学系の最前方の第１レンズ群ＬＧ１から最後方のＣＣＤ６０までの収納時における光軸方向の長さをが、従来のレンズ鏡筒に比して極めて短縮されている。１群レンズ枠１には、第１レンズ群ＬＧ１の最後部よりも後方に突出してシャッタユニット７６に当接可能な当付部１ｂ（図６及び図７）が設けられており、第１レンズ群ＬＧ１が直にシャッタユニット７６に接触することを防いでいる。
【００９１】
収納状態でカメラのメインスイッチをオンすると、制御回路１４０によってズームモータ１５０が繰出方向に駆動され、上記の各要素は以上とは逆に動作する。すなわち、カム環１１は直進案内環１４に対して回転しながら前方に繰り出され、該カム環１１と共に２群レンズ移動枠８及び第１外筒１２が前方に直進移動する。２群レンズ移動枠８の前進の初期段階では、回転伝達ばね４０の可動ばね端部４０ｂが退避位置保持面２１ｄに係合しているので２群レンズ枠６は退避位置に保たれており、２群レンズ移動枠８がある程度前方に進むと、可動ばね端部４０ｂがカム突起２１ａの先端部に達し退避位置保持面２１ｄから離れて退避カム面２１ｃに係合する（図３７）。この段階で２群レンズ枠６のレンズ筒６ａは既にＡＦレンズ枠５１の前方突出筒状部５１ｃより前方に移動しており、２群レンズ枠６が撮影位置方向への回転を開始してもＡＦレンズ枠５１とは干渉しないようになっている。そして、２群レンズ移動枠８のさらなる前進動作に伴い、可動ばね端部４０ｂが退避カム面２１ｃ上を移動して、２群レンズ枠戻しばね３９の付勢力によって２群レンズ枠６が退避位置から撮影用位置へ向けて回動を始める。
【００９２】
２群レンズ枠６が可動ばね端部４０ｂを退避カム面２１ｃ上で摺動させながら図３５の位置まで回動し、さらに２群レンズ移動枠８が前進すると、可動ばね端部４０ｂが退避カム面２１ｃから離れる。その結果、カム突起２１ａによる規制が完全に解除され、２群レンズ枠６は、２群レンズ枠戻しばね３９の付勢力によってストッパアーム６ｅを回動規制ピン３５の偏心ピン３５ｂに係合させて撮影用位置に保持される。すなわち第２レンズ群ＬＧ２の光軸が、他のレンズ群などと同じく撮影光軸Ｚ１に一致する。撮影用位置への２群レンズ枠６の回動は、ワイド端になるまでに完了する。
【００９３】
なお、収納状態から撮影状態になるときには、ＡＦレンズ枠５１が前述の後方移動端から前方に移動されるが、図６に示すように、ＡＦレンズ枠５１が前方に移動した状態でも前方突出筒状部５１ｃはローパスフィルタＬＧ４及びＣＣＤ６０の前方を覆っており、この前方突出筒状部５１ｃの先端面５１ｃ１や各側面５１ｃ３ないし５３ｃ６によって、第３レンズ群ＬＧ３以外の部分からローパスフィルタＬＧ４、ＣＣＤ６０に入射する余分な光を減らすことができる。つまり、ＡＦレンズ枠５１の前方突出筒状部５１ｃは、第３レンズ群ＬＧ３を支持するのみならず、収納状態でローパスフィルタＬＧ４及びＣＣＤ６０を収納する収納部として機能し、撮影状態ではローパスフィルタＬＧ４及びＣＣＤ６０への余分な光の入射を防ぐ遮光部として機能する。
【００９４】
可動レンズ群に関しては、撮影性能を損なわないためにその支持構造に高い精度が要求されるが、特に本レンズ鏡筒のように、第２レンズ群ＬＧ２に対して光軸方向移動のみならず退避のための揺動を行わせる場合、該第２レンズ群ＬＧ２の退避動作に関わる２群レンズ枠６と２群回動軸３３に対して要求される精度は、通常の可動部材に比して数段高いものになる。例えば、従来のレンズ鏡筒では、シャッタＳや絞Ａのような露出制御部材を内蔵する環状体内に２群回動軸３３のような回転中心軸を配設する場合、回転中心軸は露出制御部材の前方か後方のいずれかのスペースに設けることしかできず、軸長が制限されたり、片持ちの支持構造になったりしていた。しかし、２群回動軸３３のような回転中心軸と揺動軸孔６ｄのような軸孔部との間には相対回転を許容するための最低限のクリアランスが必要であるから、回転中心軸の軸長が短かかったり、片持ちの支持構造である場合、このクリアランスを起因として両者の間に倒れが生じる可能性があった。従来のレンズ支持構造では問題にならない程度の倒れも、本実施形態の要求する光学精度では排除することが必要となる。
【００９５】
本レンズ群退避構造では、図３１から分かるように、シャッタユニット７６を挟んで前後に離間して位置する前方支持板装着面８ｃと後方支持板装着面８ｅを２群レンズ枠支持板３６と２群レンズ枠支持板３７で挟み込み、該２群レンズ枠支持板３６及び２群レンズ枠支持板３７の間に２群回動軸３３を掛け渡した構造としたので、２群回動軸３３の支持構造は倒れの生じにくい両持ち構造となっている。しかも、２群回動軸３３の支持に関わる２群レンズ枠支持板３６及び３７と揺動中心筒収納孔８ｇとはシャッタユニット７６とは重ならない位置に形成されているため、２群回動軸３３の軸長は、シャッタユニット７６と無関係に（干渉させずに）長くすることができる。実際に、本実質形態の２群回動軸３３の軸長は、２群レンズ移動枠８の光軸方向長さに匹敵するほど長くなっている。これに対応して、２群レンズ枠支持板３６と２群レンズ枠支持板３７の間に挟まれる揺動中心筒６ｂの軸長も長くなっている。すなわち、揺動軸孔６ｄと２群回動軸３３の間には十分に長い係合長が確保されている。以上の構造から、２群回動軸３３に対して２群レンズ枠６の倒れが生じるおそれが少なく、２群レンズ枠６を高い精度で駆動することが可能となっている。
【００９６】
また、２群レンズ枠支持板３６と２群レンズ枠支持板３７はそれぞれ、前方支持板装着面８ｃと後方支持板装着面８ｅに突設した前方ボス８ｊと後方ボス８ｋにより位置が定められ、共通の支持板固定ビス６６によって該前方支持板装着面８ｃと後方支持板装着面８ｅに圧着される。そのため、２群レンズ移動枠８に対する２群レンズ枠支持板３６及び２群レンズ枠支持板３７の位置精度、すなわち２群レンズ移動枠８に対する２群回動軸３３の位置精度も高くすることができる。
【００９７】
なお、本実施形態では、後方支持板装着面８ｅが２群レンズ移動枠８の後端面と面一になっているのに対し、２群レンズ移動枠８の前部では前方支持板装着面８ｃよりも前方に部分円筒状部８ｄが突設されており、前方支持板装着面８ｃは厳密な意味での２群レンズ移動枠８の前端面とはなっていない。しかし、２群レンズ移動枠８が、部分円筒状部８ｄのような突出部分を有さない単純な端面形状の環状体の場合には、その前後端面を一対の軸支持板で直接に挟着するような構造としてもよい。
【００９８】
また、以上のレンズ群退避構造では、仮にワイド端から収納位置までの２群レンズ移動枠８の収納移動距離の全域を利用して徐々に２群レンズ枠６を退避回動させると、その途中で２群レンズ枠６がＡＦレンズ枠５１の前方突出筒状部５１ｃと干渉してしまうので、該収納移動距離のうち短い距離で２群レンズ枠６の退避回動を完了させ、続いてレンズ筒６ａを光軸方向後方へ平行移動させて前方突出筒状部５１ｃ上側のスペースまで後退させるための移動距離を残しておく必要がある。短い移動距離で十分な退避回動角を確保するためには、退避カム面２１ｃを、２群レンズ移動枠８の進退方向（すなわち光軸と平行な方向）に対する交差角の大きい、いわゆるリードをたたせた傾斜面としなければならない。このような退避カム面２１ｃで可動ばね端部４０ｂを押圧する際には、２群レンズ移動枠８の進退方向に対する交差角の小さい（リードをねかせた）カム面で押圧する場合に比べて、カム突起２１ａや２群レンズ移動枠８に大きな反作用力が働く。
【００９９】
カム突起２１ａは、固定環２２と同様の固定部材である。一方、２群レンズ移動枠８は直進案内されているが、図１９に示すように、固定環２２から直接に直進案内を受けているのではなく、直進案内環１４及び２群直進案内環１０といった中間部材を介在しての直進案内であり、それぞれの直進案内機構部には嵌合クリアランスがある。そのため、カム突起２１ａや２群レンズ移動枠８に大きな反作用力が働いた場合に、この嵌合クリアランスを起因として２群レンズ移動枠８とＣＣＤホルダ２１の位置関係が狂い、２群レンズ枠６の退避動作に影響してしまう可能性を考慮しなければならない。例えば、２群レンズ枠６を退避位置に回転させる際に、設計上の位置（図３０）よりもさらに退避方向へ進み過ぎてしまうと２群レンズ移動枠８の内壁面と干渉してしまうし、逆に設計上の退避位置の手前で停止してしまうとＡＦレンズ枠５１等との干渉が生じるおそれがある。
【０１００】
本レンズ群退避構造では、２群レンズ枠６を退避位置に回転させた際に、カム突起２１ａに設けたガイドキー２１ｅをキー溝８ｐに係合させることによって、該カム突起２１ａと２群レンズ移動枠８の位置ずれを防ぎ、２群レンズ枠６を正確な退避位置に保持させることが可能になっている（図２４参照）。具体的には、可動ばね端部４０ｂが退避位置保持面２１ｄに係合して２群レンズ枠６の退避状態が保たれ、かつ２群レンズ移動枠８に後退する余地が残されている収納動作の途中の状態において、ガイドキー２１ｅが、２群レンズ枠支持板３７に形成したガイドキー進入溝３７ｇを通って揺動中心筒収納孔８ｇ内に進入し、キー溝８ｐに係合する。ガイドキー２１ｅとキー溝８ｐはそれぞれ光軸と平行な溝と凸部であるから、該ガイドキー２１ｅとキー溝８ｐが係合すると、２群レンズ移動枠８とカム突起２１ａは、光軸方向には相対移動自在で、キー溝８ｐの溝幅方向への相対移動は規制される。キー溝８ｐの溝幅方向は２群レンズ枠６の回動方向と概ね一致している。したがって、仮に退避カム面２１ｃによる２群レンズ枠６の押圧時に２群レンズ移動枠８に反作用が働いたとしても、ガイドキー２１ｅとキー溝８ｐの係合によって２群レンズ移動枠８とカム突起２１ａは適切な位置関係に保たれるので、２群レンズ枠６の退避位置がずれるおそれがない。
【０１０１】
なお、本実施形態では、ガイドキー２１ｅとキー溝８ｐを係合させるタイミングを、退避カム面２１ｃによる２群レンズ枠６の退避動作の完了後としているが、この係合開始のタイミングを、退避動作の途中または退避動作の前に設定してもよい。要は、２群レンズ枠６を最終的に退避位置に保持させたときに、２群レンズ移動枠８とカム突起２１ａの位置関係が正確に出ていればよいのである。ガイドキー２１ｅとキー溝８ｐを係合させるタイミングは、例えば、ガイドキー２１ｅの光軸方向への形成領域を変化させることによって任意に設定することができる。
【０１０２】
また、本実施形態ではカム突起２１ａ側のガイドキー２１ｅを凸部とし、２群レンズ移動枠８側のキー溝８ｐを凹部としているが、凹凸の関係は逆でもよい。
【０１０３】
さらに、本実施形態では退避カム面２１ｃを有するカム突起２１ａにガイドキー２１ｅを形成しているが、ガイドキー２１ｅに相当する部分を、ＣＣＤホルダ２１においてカム突起２１ａ以外の箇所に形成することも可能である。但し、構造の簡略化という観点からは、ガイドキー２１ｅは退避カム面２１ｃと共にカム突起２１ａに形成した方がよい。また、２群レンズ移動枠８（厳密には２群レンズ枠６）側との係合箇所であるカム突起２１ａ自体にガイドキー２１ｅを形成した方が、２群レンズ移動枠８に対する正確な位置出しという観点からも効果的である。
【０１０４】
また、２群レンズ枠６の退避回動時に２群レンズ移動枠８やカム突起２１ａに働く前述の反作用力に加え、レンズ群退避機構を構成する部品の位置精度も、２群レンズ枠６の動作精度に影響する。前述の通り、２群レンズ枠６に与えられる退避回動量は過度であっても不足していても好ましくないが、本実施形態では特に、レンズ筒６ａやストッパアーム６ｅを退避状態において２群レンズ移動枠８の内壁面に非常に近接させることで省スペース化を図っている関係上（図３０参照）、２群レンズ枠６に対して図３０に示す適正な退避位置を超えさせるような力が加わると、退避機構にストレスがかかってしまうので、これを回避することが求められる。
【０１０５】
これを解決するため本レンズ群退避構造では、２群レンズ枠６の退避回動に際してカム突起２１ａの退避カム面２１ｃと退避位置保持面２１ｄが当接する箇所を、退避作用アーム６ｊではなく回転伝達ばね４０の可動ばね端部４０ｂとし、該回転伝達ばね４０が撓むことによって２群レンズ枠６の多少の移動誤差を吸収できるようにしている。前述のように、回転伝達ばね４０は、通常の退避動作では図３５や図３７の形状以上には撓まずに２群レンズ枠６へ回転力を伝達するが、図３７の状態で可動ばね端部４０ｂを最大でθ１撓ませる余地が残されているので、仮にカム突起２１ａが図３７の位置よりも若干左側にずれるような位置誤差があっても、可動ばね端部４０ｂが固定ばね端部４０ａに接近する方向に撓んでこの位置誤差を吸収することができる。すなわち、２群レンズ枠６（レンズ筒６ａやストッパアーム６ｅ）が２群レンズ移動枠８（レンズ筒進入凹部８ｑやストッパアーム進入凹部８ｒ）の内周面に当て付いた状態でさらにカム突起２１ａによる押圧力が作用しても、回転伝達ばね４０が撓むことで２群レンズ枠６の退避機構に対して過度なストレスがかかるのを防ぐことができる。
【０１０６】
本レンズ群退避構造ではまた、図３０に示すように、退避位置に保持される２群レンズ枠６の揺動アーム６ｃは、露出制御ＦＰＣ基板７７が挿通されている直進案内溝８ａ-Ｗの内側に隣接しており、該揺動アーム６ｃの外径側の面が直進案内溝８ａ-Ｗの底部の一部を塞ぐようになっている。逆に言えば、２群回動軸３３と退避光軸Ｚ２を結ぶ線分の中間位置の外径側に、直進案内溝８ａ-Ｗが形成されて露出制御ＦＰＣ基板７７が通されている。これにより、２群レンズ枠６が退避位置にあるときに揺動アーム６ｃが露出制御ＦＰＣ基板７７を鏡筒内径側から支持することが可能になっており、該支持状態での露出制御ＦＰＣ基板７７と２群レンズ枠６との関係を図４３に実線で示した。なお、同図に二点鎖線で示しているのは、撮影用位置にあるときの２群レンズ枠６である。図４３から分かるように、揺動アーム６ｃは、露出制御ＦＰＣ基板７７のＵ字状部７７ｂと第１直線状部７７ａを内側から支えて、露出制御ＦＰＣ基板７７が鏡筒内径方向に弛むことを防いでいる。
【０１０７】
具体的には、揺動アーム６ｃには、退避時に第１直線状部７７ａと平行をなす直線支持面６ｑと、該直線支持面６ｑの後方に隣接しＵ字状部７７ｂの形状に合わせて傾斜させた傾斜支持面６ｒと、該傾斜支持面６ｒより後方に突出するＦＰＣ支持突起部６ｓとが設けられている。２群レンズ枠６の退避位置では、直線支持面６ｑが第１直線状部７７ａを支えるように位置し、傾斜支持面６ｒとＦＰＣ支持突起部６ｓがＵ字状部７７ｂを支えるように位置する。
【０１０８】
レンズ鏡筒において光軸方向への進退部材と固定部材とを接続するフレキシブルプリント配線板（フレキシブルプリント回路基板、以下、ＦＰＣ）は、進退部材の最大繰出状態に対応する長さが必要であるため、進退部材の繰出量が最小のとき、すなわち鏡筒収納状態ではＦＰＣの長さが余剰となって弛みを生じやすい。特に、本実施形態では、第２レンズ群ＬＧ２を退避光軸Ｚ２上に退避させることでズームレンズ鏡筒７１の収納時の光軸方向長は非常に短縮されているので、その傾向が強い。ＦＰＣの弛み部分が他の鏡筒構成部材と干渉したり挟み込まれると故障や破損の原因となるので、弛みを防ぐ構造が必要となるが、従来のレンズ鏡筒におけるＦＰＣの弛み防止構造は複雑なものが多かった。これに対し、本実施形態の７１では、露出制御ＦＰＣ基板７７の弛みが生じやすい鏡筒収納状態が２群レンズ枠６の退避状態であることに着目して、退避位置にある該２群レンズ枠６を利用して露出制御ＦＰＣ基板７７を支持するようにしたため、簡単な構造で確実に露出制御ＦＰＣ基板７７の弛みを防ぐことができる。
【０１０９】
本実施形態の２群レンズ枠６の退避構造では、２群レンズ枠６が退避位置へ動作するとき回転しつつ後退するので、その移動軌跡は、撮影光軸Ｚ１から斜め後方へ向けて進むものとなる。一方、撮影状態において２群レンズ枠６の後方にはＡＦレンズ枠５１が位置している。ＡＦレンズ枠５１の前方突出筒状部５１ｃには、図３９ないし図４１に示すように、その先端面５１ｃ１から上側の側面５１ｃ５にかけて退避方向斜面５１ｈが形成されている。退避方向斜面５１ｈは、撮影光軸Ｚ１を中心とする放射方向（外径方向）に進むにつれて徐々に光軸方向後方へ向かうように傾斜しており、端的に言えば、２群レンズ枠６のレンズ筒６ａの移動軌跡に沿って切り欠かれた面となっている。また、退避方向斜面５１ｈは、レンズ筒６ａの外形形状に対応する湾曲状の凹面となっている。
【０１１０】
前述のように、鏡筒収納動作に際しては、２群レンズ枠６の退避動作が生じる前に、ＡＦレンズ枠５１がＣＣＤホルダ２１の移動規制面２１ｂに当て付く後方移動端（収納位置）まで移動される（図４０及び図４１）。この状態で２群レンズ枠６の退避動作を行うと、レンズ筒６ａの後端部が斜め後方に移動して退避方向斜面５１ｈに接近し、該退避方向斜面５１ｈをかすめるようにして図４１の位置まで移動される。つまり、退避方向斜面５１ｈを切り欠いた分だけ、ＡＦレンズ枠５１に近い位置で２群レンズ枠６の退避動作を行わせることができる。
【０１１１】
ここで退避方向斜面５１ｈのような傾斜面が存在しないものと仮定すると、ＡＦレンズ枠５１との干渉を避けるために、２群レンズ枠６の退避位置への回転を本実施形態よりも早い段階で完了させなければならない。そのためには、２群レンズ移動枠８の後退移動量をより長くしたり、カム突起２１ａの突出量を大きくする必要があるが、これらはレンズ鏡筒の小型化に反する。また、２群レンズ移動枠８の後退移動量が一定であるならば、光軸に対する退避カム面２１ｃの傾斜角を大きくしなければならないが、カム面の傾斜があまり大きいと押圧時の反作用力（抵抗）が大きくなり、動作の円滑性という観点から好ましくない。これに対し本実施形態の退避構造では、退避方向斜面５１ｈを形成して、可能な限りＡＦレンズ枠５１に近い位置まで後退しても２群レンズ枠６の退避動作を実行できるようにしたので、比較的少ない２群レンズ移動枠８の後退移動量であっても、退避カム面２１ｃを無理のない形状にすることができ、小型化と動作の円滑性を両立させることができる。また、ＣＤホルダ２１にはＡＦレンズ枠５１の退避方向斜面５１ｈに連続する形状の退避方向斜面２１ｆが形成されており、この退避方向斜面２１ｆは退避方向斜面５１ｈと同様に機能する。なお、本実施形態ではＡＦレンズ枠５１が光軸方向への可動部材であるが、退避方向斜面５１ｈによる上記効果は、ＡＦレンズ枠５１に相当する部材が光軸方向へ移動しないタイプのレンズ鏡筒においても有効である。
【０１１２】
以上の通り、本実施形態の２群レンズ枠６の退避構造では、ＡＦレンズ枠５１が後方移動端に移動済みの状態（図４０及び図４１）では、２群レンズ枠６が退避回転及び後退動作を行っても該ＡＦレンズ枠５１と干渉しないように設計されており、メインスイッチがオフされたときには、制御回路１４０によって、まずＡＦモータ１６０を駆動してＡＦレンズ枠５１を後方移動端に移動させるように制御される。しかし、仮にメインスイッチがオフされても何らかの原因でＡＦレンズ枠５１が後方移動端まで移動されなかった場合には、２群レンズ移動枠８と共に光軸方向後方に移動しながら退避位置へ向けて回転している最中の２群レンズ枠６の移動軌跡上に、ＡＦレンズ枠５１が重なってしまうおそれがある（図４６、図４４）。
【０１１３】
これに対するフェイルセーフ構造として、２群レンズ枠６には第２レンズ群ＬＧ２よりも光軸方向後方に突出する後方突出部６ｍが形成されており、ＡＦレンズ枠５１の前方突出筒状部５１ｃの先端面５１ｃ１には、該後方突出部６ｍに対向する位置に、第３レンズ群ＬＧ３よりも前方に突出するリブ状の前方突出部５１ｆが形成されている（図４０、図４１、図４４ないし図４７参照）。図４７に示すように、前方突出部５１ｆは、撮影光軸Ｚ１と直交する平面方向において、２群レンズ枠６が撮影用位置から退避位置へ回転するときの後方突出部６ｍ（ＡＦ枠当接面６ｎ）の移動軌跡に対応する領域に形成されている。
【０１１４】
したがって、仮にＡＦレンズ枠５１が後方移動端まで移動せず不完全な後退位置で停止した状態で２群レンズ枠６が後退及び退避回転を行っても、ＡＦレンズ枠５１の前方突出部５１ｆに対して必ず後方突出部６ｍのＡＦ枠当接面６ｎが最初に当接するため、第２レンズ群ＬＧ２がＡＦレンズ枠５１側に接触して傷ついてしまうおそれがない。逆に言えば、図４７に示すように、後方突出部６ｍの移動軌跡は、２群レンズ枠６のいずれの角度位置でも第３レンズ群ＬＧ３と重ならないようになっているので、２群レンズ枠６の他の箇所が第３レンズ群ＬＧ３に接触して傷つけるおそれもない。なお、揺動アーム６ｃには、後方突出部６ｍと平行して前述のＦＰＣ支持突起部６ｓが設けられているが、ＦＰＣ支持突起部６ｓよりも後方突出部６ｍの方が後方への突出量が大きいので、ＦＰＣ支持突起部６ｓが第３レンズ群ＬＧ３に接触することはない。以上の構造により、２群レンズ枠６とＡＦレンズ枠５１の当接箇所は常に後方突出部６ｍと前方突出部５１ｆに限定され、第２レンズ群ＬＧ２や第３レンズ群ＬＧ３の光学性能には悪影響が及ばない。また、後退動作及び退避回転中の２群レンズ枠６が後方突出部６ｍを介して前方突出部５１ｆを押圧することで、停止しているＡＦレンズ枠５１を後方に押し下げることも可能である。
【０１１５】
後方突出部６ｍのＡＦ枠当接面６ｎは撮影光軸Ｚ１と直交する平面であるのに対し、図４５及び図４６に示すように、前方突出部５１ｆの前面は、撮影光軸Ｚ１と直交する平面に対してθ２だけ傾斜する傾斜当接面５１ｇとなっている。傾斜当接面５１ｆは、２群レンズ枠６が退避方向へ回転するとき後方突出部６ｍが移動する方向（図４５ないし図４７の上方）に進むにつれて徐々に光軸方向後方へ傾斜するように形成されている。これと異なり、仮に前方突出部５１ｆの前面がＡＦ枠当接面６ｎと平行な面であると、２群レンズ枠６が退避回転している途中で両面が接触した場合に摺動抵抗が大きくなり、２群レンズ枠６の退避回転が妨げられるおそれがある。これに対し、前方突出部５１ｆの前面を傾斜当接面５１ｇのような傾斜面とすることによって、２群レンズ枠６が退避回転しているときにＡＦ枠当接面６ｎと接触しても、摺動抵抗を軽減して確実に退避させることができる。本実施形態では望ましい傾斜角としてθ２は３度に設定されている。
【０１１６】
また、後方突出部６ｍと前方突出部５１ｆが接触する程ではないが、ＡＦレンズ枠５１完全に後退されていないときには、退避方向斜面５１ｈをレンズ筒６ａの後端部（厳密には群レンズ保持蓋９）に接触させて、傾斜当接面５１ｇと同様のフェイルセーフ面として機能させることもできる。
【０１１７】
本レンズ退避機構はまた、第２レンズ群ＬＧ２の光軸が撮影光軸Ｚ１と一致しない場合などにおいて、該第２レンズ群ＬＧ２の光軸位置を、撮影光軸Ｚ１と直交する平面方向に移動させて調節することが可能である。光軸位置の調整機構は二種類搭載されており、うち一つは、２群レンズ移動枠８に対する２群レンズ枠支持板３６、３７の位置調整機構であり、この調整は第１偏心軸部材３４Ｘ及び第２偏心軸部材３４Ｙを回転させることで行う。他方は、ストッパアーム６ｅに対する偏心ピン３５ｂの当接位置調整機構であり、この調整は回動規制ピン３５を回転させることで行う。
【０１１８】
まず２群レンズ移動枠８に対する２群レンズ枠支持板３６、３７の位置調整機構を説明する。第１偏心軸部材３４Ｘ及び第２偏心軸部材３４Ｙの支持構造については前述したが繰り返すと、図２８、図３２及び図３３に示すように、第１偏心軸部材３４Ｘの前方偏心ピン３４Ｘ-ｂは、第１縦長孔３６ａに対して該第１縦長孔３６ａの長手（長軸）方向には摺動可能、かつ該長手方向と直交する幅方向には移動不能に係合し、前方偏心ピン３４Ｙ-ｂは、横長孔３６ｅに対して該横長孔３６ｅの長手（長軸）方向には摺動可能、かつ該長手方向と直交する幅方向には移動不能に係合している。第１縦長孔３６ａの長手方向と横長孔３６ｅの長手方向は互いに直交しており、以下では、カメラの上下方向と平行な前者をＹ方向、カメラの左右方向と平行な後者をＸ方向と称する。
【０１１９】
後方の２群レンズ枠支持板３７に形成される第１縦長孔３７ａは、その長軸が２群レンズ枠支持板３６の第１縦長孔３６ａの長軸と平行である。すなわち、第１縦長孔３７ａはＹ方向に長い長孔である。この前後の第１縦長孔３６ａ、３７ａは、２群レンズ枠支持板３６、３７の対向する位置に形成されている。また、２群レンズ枠支持板３７の横長孔３７ｅは、その長軸が２群レンズ枠支持板３６の横長孔３６ｅの長軸と平行である。すなわち、横長孔３７ｅはＸ方向に長い長孔である。この前後の横長孔３６ｅ、３７ｅは、２群レンズ枠支持板３６、３７の対向する位置に形成されている。図２９に示すように、後方偏心ピン３４Ｘ-ｃは前方偏心ピン３４Ｘ-ｂと同様に、第１縦長孔３７ａに対してＹ方向に摺動可能かつＸ方向には移動不能に係合し、前方偏心ピン３４Ｙ-ｂは、横長孔３７ｅに対してＸ方向に摺動可能かつＹ方向には移動不能に係合している。
【０１２０】
上記の第１縦長孔３６ａ、３７ａや横長孔３６ｅ、３７ｅと同様に、第２縦長孔３６ｆ、３７ｆも互いの長軸が平行であり、かつ２群レンズ枠支持板３６、３７の対向する位置に形成されている。第２縦長孔３６ｆ、３７ｆは、第１縦長孔３６ａ、３７ａと平行な、Ｙ方向への長孔である。２群レンズ移動枠８に突設した前方ボス８ｊと後方ボス８ｋはそれぞれ、この第２縦長孔３６ｆ、３７ｆに対して、Ｙ方向に摺動可能かつＸ方向には移動不能に係合している。
【０１２１】
図３１に示すように、大径軸部３４Ｘ-ａと大径軸部３４Ｙ-ａはそれぞれ、偏心軸支持孔８ｆと偏心軸支持孔８ｉに対して径方向に移動しないように係合しているため、第１偏心軸部材３４Ｘは大径軸部３４Ｘ-ａの中心軸である調整軸ＰＸを中心として回転し、第２偏心軸部材３４Ｙは大径軸部３４Ｙ-ａの中心軸である調整軸ＰＹ１を中心として回転する。前方偏心ピン３４Ｘ-ｂ及び後方偏心ピン３４Ｘ-ｃはそれぞれ、調整軸ＰＸに対してＹ方向に偏心させて突設されている。前述の通り、前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃは同軸かつ同径に形成されている。また、前方偏心ピン３４Ｙ-ｂ及び後方偏心ピン３４Ｙ-ｃはそれぞれ、調整軸ＰＹ１に対してＸ方向に偏心させて突設されており（図３３参照）、この前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃも同軸かつ同径に形成されている。
【０１２２】
したがって、調整軸ＰＹ１を中心に第２偏心軸部材３４Ｙを回転させると、前方偏心ピン３４Ｙ-ｂ及び後方偏心ピン３４Ｙ-ｃに対して、調整軸ＰＹ１を中心とする弧状の軌跡で概ねＹ方向への移動力が与えられる。前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃはそれぞれ横長孔３６ｅと横長孔３７ｅに対してＹ方向への相対移動が規制された状態で係合しているため、各偏心ピン３４Ｙ-ｂ、３４Ｙ-ｃを各横長孔３６ｅ、３７ｅ内でＸ方向に移動させつつ、２群レンズ枠支持板３６及び２群レンズ枠支持板３７に対してＹ方向の移動力が伝達される。ここで、２群レンズ枠支持板３６に形成した残る２つの第１縦長孔３６ａと第２縦長孔３６ｆはいずれもＹ方向への長孔であり、２群レンズ枠支持板３７に形成した残る２つの第１縦長孔３７ａと第２縦長孔３７ｆもＹ方向への長孔であるから、２群レンズ枠支持板３６と２群レンズ枠支持板３７は、各縦長孔に係合する突起（前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃ、前方ボス８ｊ及び後方ボス８ｋ）に案内されてＹ方向へ直進移動する。その結果、２群レンズ移動枠８に対する２群レンズ枠６の位置がＹ方向に変位し、第２レンズ群ＬＧ２がＹ方向に光軸調整される。
【０１２３】
調整軸ＰＸを中心に第１偏心軸部材３４Ｘを回転させると、前方偏心ピン３４Ｘ-ｂ及び後方偏心ピン３４Ｘ-ｃに対して、調整軸ＰＸを中心とする弧状の軌跡で概ねＸ方向への移動力が与えられる。前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃはそれぞれ第１縦長孔３６ａと第１縦長孔３７ａに対してＸ方向への相対移動が規制された状態で係合しているため、各偏心ピン３４Ｘ-ｂ、３４Ｘ-ｃを各第１縦長孔３６ａ、３７ａ内でＹ方向に移動させつつ、２群レンズ枠支持板３６及び２群レンズ枠支持板３７に対してＸ方向の移動力が伝達される。ここで、前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃはそれぞれ横長孔３６ｅと横長孔３７ｅに対してＸ方向に移動可能であるが、その下方の前方ボス８ｊと後方ボス８ｋはそれぞれ第２縦長孔３６ｆと第２縦長孔３７ｆに対してＸ方向への移動が規制されているから、２群レンズ枠支持板３６と２群レンズ枠支持板３７は、第２縦長孔３６ｆと第２縦長孔３７ｆを有する下端部側を中心とする揺動に近い傾動を行う。この傾動（揺動近似動作）は、第２偏心軸部材３４Ｙの前方偏心ピン３４Ｙ - ｂと後方偏心ピン３４Ｙ - ｃに対する横長孔３６ｅと横長孔３７ｅのＸ方向への相対移動と、前方ボス８ｊと後方ボス８ｋに対する第２縦長孔３６ｆと第２縦長孔３７ｆのＹ方向への相対移動とを合成した動作である。２群レンズ枠６を支持する２群回動軸３３は、該傾動の仮想中心である前後のボス８ｊ、８ｋと第２縦長孔３６ｆ、３７ｆの係合位置付近から離れた位置にあるため、２群レンズ枠支持板３６及び２群レンズ枠支持板３７の当該傾動は、該２群回動軸３３の位置ではＸ方向への直線移動に近似するものとして扱うことができる。したがって、第１偏心軸部材３４Ｘの回転によって第２レンズ群ＬＧ２の位置がＸ方向に変化する。
【０１２４】
なお、２つの偏心軸部材を用いた光軸調整機構としては、図５０に示すような別形態も可能である。図５０の調整機構では、前方ボス８ｊと後方ボス８ｋが係合する対象が、Ｙ方向とＸ方向のいずれに対しても傾斜した傾斜長孔（移動ガイド手段、第３の長孔）３６ｆ’、３７ｆ’である点が異なる。傾斜長孔３６ｆ’、３７ｆ’は互いに平行で、光軸方向の対称位置に形成されている。傾斜長孔３６ｆ’、３７ｆ’はＸ方向とＹ方向の両成分を含んでいるため、当該構造において第２偏心軸部材３４Ｙを回動させたときには、前方ボス８ｊと後方ボス８ｋに対して傾斜長孔３６ｆ’、３７ｆ’はＹ方向に移動しながらＸ方向へも若干変位する。その結果、２群レンズ枠支持板３６と２群レンズ枠支持板３７は、傾斜長孔３６ｆ’、３７ｆ’を有する下端部付近を多少Ｘ方向に変位させつつ、第１偏心軸部材３４Ｘの前方偏心ピン３４Ｘ - ｂと後方偏心ピン３４Ｘ - ｃに対する第１縦長孔３６ａ、３７ａの係合位置を変化させてＹ方向に移動する（傾動する）。また、第１偏心軸部材３４Ｘを回動させたときには、前方ボス８ｊと後方ボス８ｋに対して傾斜長孔３６ｆ’、３７ｆ’がＸ方向に移動しながらＹ方向へも若干変位し、２群レンズ枠支持板３６と２群レンズ枠支持板３７は、該傾斜長孔３６ｆ’、３７ｆ’を有する下端部付近をＹ方向へ若干変位させつつ、第２偏心軸部材３４Ｙの前方偏心ピン３４Ｙ - ｂと後方偏心ピン３４Ｙ - ｃに対する横長孔３６ｅ、３７ｅの係合位置を変化させてＸ方向へ移動する（傾動する）。この２種類の移動を組み合わせれば、２群レンズ枠６の位置を光軸と直交する平面内で適宜変化させることができる。
【０１２５】
第１偏心軸部材３４Ｘと第２偏心軸部材３４Ｙによる第２レンズ群ＬＧ２の光軸調整は、支持板固定ビス６６を緩めた状態で行い、調整が完了したら支持板固定ビス６６を締め込む。すると、２群レンズ枠支持板３６と２群レンズ枠支持板３７は調整後の位置関係を維持しつつ前方支持板装着面８ｃと後方支持板装着面８ｅを挟着し、２群回動軸３３も調整後の位置に保たれる。第２レンズ群ＬＧ２の光軸位置は２群回動軸３３を基準として決まるので、結果として調整後の光軸位置が維持される。なお、光軸位置調整の結果、２群レンズ枠支持板３６、３７と共に支持板固定ビス６６も移動することになるが、図３１に示すようにビス軸部６６ａはビス挿通孔８ｈに対して余裕をもって遊嵌しており、光軸位置調整程度の移動量では支持板固定ビス６６と２群レンズ移動枠８が干渉しないようになっている。
【０１２６】
移動対象を２次元的に移動させて位置調整を行う機構としては、特定の直線方向に進退移動可能な第１のステージの上に、これと直交する直線方向への進退が可能な第２のステージを設け、さらにその上に駆動対象を支持したものが代表的なタイプとして知られている。しかし、このような２ステージ式の支持構造は構造が複雑になってしまうという難点がある。これに対し、本レンズ鏡筒の光軸位置調整機構は、２群レンズ枠支持板３６、３７の各々がＸ方向とＹ方向の両方に移動可能に支持されているため、２次元的な調整機構を簡単な構造で実現することができた。なお、実施形態では、２群レンズ枠６の支持安定性を高めるために前後に離間する一対の２群レンズ枠支持板３６、３７を備えているが、原理的には２群レンズ枠支持板３６、３７のうちいずれか一つだけで２群レンズ枠６を支持することが可能であり、この場合、調整機構も当該一つの２群レンズ枠支持板のみを対象として設ければよい。
【０１２７】
以上の光軸調整機構では、２群レンズ枠支持板３６及び２群レンズ枠支持板３７の位置調整の基準となる第１偏心軸部材３４Ｘの前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃ、第２偏心軸部材３４Ｙの前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃ、及び前方ボス８ｊと後方ボス８ｋという、前後で対をなす突出部をそれぞれ前後同軸に形成しているため、第１偏心軸部材３４Ｘまたは第２偏心軸部材３４Ｙを回転したときに、前後の２群レンズ枠支持板３６と２群レンズ枠支持板３７は互いに平行を維持しつつ、同一の軌跡で（同一方向へ同量）移動する。例えば、第１偏心軸部材３４Ｘの前方偏心ピン３４Ｘ-ｂと後方偏心ピン３４Ｘ-ｃのいずれに対して回転操作を行っても、２群レンズ枠支持板３６及び２群レンズ枠支持板３７はＸ方向へ均等に（同量）移動し、第２偏心軸部材３４Ｙの前方偏心ピン３４Ｙ-ｂと後方偏心ピン３４Ｙ-ｃのいずれに対して回転操作を行っても、２群レンズ枠支持板３６及び２群レンズ枠支持板３７はＹ方向に均等に（同量）移動する。後述するように、本実施形態では２群レンズ枠支持板３６側の前方偏心ピン３４Ｘ-ｂと前方偏心ピン３４Ｙ-ｂに対してドライバで回転力を与えるが、このとき後方の２群レンズ枠支持板３７が２群レンズ枠支持板３６に対してよじれることなく追従する。よって、光軸調整に際して２群回動軸３３の倒れが生じるおそれがなく、第２レンズ群ＬＧ２の光軸調整を精度よく行うことができる。
【０１２８】
また、第１偏心軸部材３４Ｘ及び第２偏心軸部材３４Ｙは、シャッタユニット７６を挟む前後位置に離間して設けた２群レンズ枠支持板３６と２群レンズ枠支持板３７によって挟まれるので、２群回動軸３３と同様にその軸長が２群レンズ移動枠８の光軸方向長さに匹敵するほど長く確保されている、よって、２群レンズ移動枠８に対する倒れが生じにくく、より正確な光軸調整が達成される。
【０１２９】
続いて、ストッパアーム６ｅと偏心ピン３５ｂの関係による第２レンズ群ＬＧ２の光軸位置調整を説明する。図２９及び図３０に示すように、回動規制ピン３５は大径軸部３５ａを回動規制ピン挿通孔８ｍに対して回動可能に係合させており、偏心ピン３５ｂを回動規制ピン挿通孔８ｍの後方へ突出させている。図２７に示すように、偏心ピン３５ｂはストッパアーム６ｅの移動軌跡上に位置している。偏心ピン３５ｂは、大径軸部３５ａの中心を通る調整軸ＰＹ２に対してＸ方向に偏心した位置に突設されており（図３４）、該調整軸ＰＹ２を中心として回動規制ピン３５を回転させると、偏心ピン３５ｂは概ねＹ方向に変位する。前述の通り、偏心ピン３５ｂは２群レンズ枠６の撮影用位置を決める部材であるから、該偏心ピン３５ｂがＹ方向に変位すると、結果として撮影用位置における第２レンズ群ＬＧ２の光軸位置がＹ方向に移動される。この回動規制ピン３５による光軸位置調整は、第２偏心軸部材３４Ｙによる調整と併用することができ、特に第２偏心軸部材３４Ｙによる調整量だけでは不十分な場合の補助的調整として回動規制ピン３５を用いるとよい。
【０１３０】
図２８に示すように、第１偏心軸部材３４Ｘ、第２偏心軸部材３４Ｙ及び回動規制ピン３５のそれぞれにおけるドライバ係合凹部３４Ｘ-ｄ、３４Ｙ-ｄ及び３５ｃは、いずれも２群レンズ移動枠８の前方に露出している。また、支持板固定ビス６６のドライバ係合凹部６６ｂも２群レンズ移動枠８の前方に露出している。よって、第２レンズ群ＬＧ２の光軸位置調整作業は、全て２群レンズ移動枠８の前方から行うようになっている。一方、２群レンズ移動枠８の外側に取り付けられる第１外筒１２には、レンズバリヤ機構を支持する内径フランジ１２ｃが内径側に形成されており、この内径フランジ１２ｃは、１群抜止環３と共に２群レンズ移動枠８の前方を塞ぐようになっている。
【０１３１】
図４８及び図４９に示すように、第１外筒１２の内径フランジ１２ｃには、ドライバ係合凹部３４Ｘ-ｄ、３４Ｙ-ｄ、３５ｃ及び６６ｂを前方に露出させる４箇所の円形のドライバ挿通孔（第１ないし第４の回転操作孔）１２ｄ、１２ｅ、１２ｆ及び１２ｇが、光軸方向に貫通して形成されている。また、１群抜止環３において、これらのドライバ挿通孔１２ｄ、１２ｅ、１２ｆ及び１２ｇと重なる箇所も円形状に切り欠かれている。これらのドライバ挿通孔１２ｄ、１２ｅ、１２ｆ及び１２ｇを形成したことによって、第１外筒１２を取り付けた状態で、ドライバ係合凹部３４Ｘ-ｄ、３４Ｙ-ｄ、３５ｃ及び６６ｂのいずれに対しても前方からドライバを係合させることが可能となっている。ドライバ挿通孔１２ｄ、１２ｅ、１２ｆ及び１２ｇは、バリヤカバー１０１とその背後に位置する前述のレンズバリヤ機構を取り外すことによって露出し、事実上、レンズバリヤ機構以外の鏡筒構成要素を分解せずにカメラの完成状態のまま第２レンズ群ＬＧ２の光軸位置調整を行うことができる。そのため、仮に組立時に第２レンズ群ＬＧ２の位置誤差が生じても、組立の最終工程で容易に調整することができ、作業性に優れている。
【０１３２】
以上のように、実施形態のズームレンズ鏡筒７１は、収納時における光軸方向の長さを従来のレンズ鏡筒に比して極めて短縮することが可能となっているが、ズームレンズ鏡筒７１の具体的構造は本発明を実施可能な一例であり、本発明の技術思想は実施形態に限定されるものではない。例えば、実施形態では、退避させる光学要素を第２レンズ群ＬＧ２としたが、本発明は、レンズ群を問わず、あるいは絞、シャッタ及びローパスフィルタ等についても、退避光学要素とすることができる。また、実施形態はズームレンズ鏡筒であるが、本発明は、撮影状態から収納状態になるときに鏡筒の長さを短縮させるものであれば、単焦点式のレンズ鏡筒に適用することも可能である。また、実施形態は、いわゆるデジタルスチルカメラに適用したものであるが、本発明はそれ以外の光学機器に適用することも可能である。
【０１３３】
また、上記の実施形態では、第２レンズ群ＬＧ２の位置調整は、レンズ鏡筒の前方からドライバを挿入して行うようになっているが、レンズ鏡筒の構成により後方（結像面側）からのアクセスの方が容易な場合には、偏心軸部材３４Ｘ、３４Ｙ、回動規制ピン３５、支持板固定ビス６６に相当する部材は後方からの操作によって回転させるようにしてもよい。要は、退避光学要素の位置調整に関するこれらの部材を全て同方向から操作可能にすることで、作業効率が向上すればよいのである。
【０１３４】
また、実施形態のズームレンズ鏡筒７１は、２群レンズ枠６の回動中心軸３３が撮影光軸Ｚ１と平行であるが、退避光学要素を退避回動させる回動中心軸と撮影光学系の光軸とが非平行な形態のレンズ鏡筒においても、本発明は適用可能である。
【０１３６】
【発明の効果】
以上のように本発明によれば、退避光学要素を簡単な構造で位置調整することができ、かつその位置調整用の操作部材を全て同方向から操作することができるので、調整時の作業性にも優れている。
【図面の簡単な説明】
【図１】本発明を適用したズームレンズ鏡筒の分解斜視図である。
【図２】図１のズームレンズ鏡筒における、第１レンズ群の支持機構に関する部分の分解斜視図である。
【図３】図１のズームレンズ鏡筒における、第２レンズ群の支持機構に関する部分の分解斜視図である。
【図４】図１のズームレンズ鏡筒における、固定環から第３外筒までの繰出機構に関する部分の分解斜視図である。
【図５】図１のズームレンズ鏡筒に、ズームモータとファインダユニットを加えた完成状態の斜視図である。
【図６】図１のズームレンズ鏡筒のワイド端とテレ端を示す、該ズームレンズ鏡筒を搭載したカメラの縦断面図である。
【図７】図６カメラの鏡筒収納状態の縦断面図である。
【図８】固定環の展開平面図である。
【図９】ヘリコイド環の展開平面図である。
【図１０】ヘリコイド環の内周面側の構成要素を透視して示す展開平面図である。
【図１１】第３外筒の展開平面図である。
【図１２】直進案内環の展開平面図である。
【図１３】カム環の展開平面図である。
【図１４】カム環の内周面側の２群案内カム溝を透視して示す展開平面図である。
【図１５】直進案内環の展開平面図である。
【図１６】２群レンズ移動枠の展開平面図である。
【図１７】第２外筒の展開平面図である。
【図１８】第１外筒の展開平面図である。
【図１９】本実施形態のズームレンズ鏡筒の主要な部材の関係を概念的に示す図である。
【図２０】２群レンズ枠の支持機構の分解斜視図である。
【図２１】図２０の支持機構を組み合わせた状態の前方斜視図である。
【図２２】同後方斜視図である。
【図２３】後方の２群レンズ枠支持板のカム突起挿脱開口に対してカム突起が挿入されつつある状態を示す後方斜視図である。
【図２４】２群レンズ移動枠の単体正面図である。
【図２５】２群レンズ移動枠の単体斜視図である。
【図２６】２群レンズ枠とシャッタユニットを組み付けた状態の２群レンズ移動枠の前方斜視図である。
【図２７】同後方斜視図である。
【図２８】同正面図である。
【図２９】同背面図である。
【図３０】図２９の状態から２群レンズ枠が退避した状態を示す背面図である。
【図３１】図２８のXXXI-XXXI断面線に沿う断面図である。
【図３２】図２８の状態で撮影用位置に保持される２群レンズ枠を透視して示した正面図である。
【図３３】第１と第２の偏心軸部材による第２レンズ群の光軸調整機構の要部を拡大して示す正面図である。
【図３４】回動規制ピンによる第２レンズ群の光軸調整機構の要部を拡大して示す正面図である。
【図３５】撮影用位置に保持される２群レンズ枠とカム突起の関係を示す正面図である。
【図３６】２群レンズ枠がカム突起の退避カム面により退避位置近傍まで回動された状態を示す正面図である。
【図３７】２群レンズ枠がカム突起の退避位置保持面により退避位置に保持された状態を示す正面図である。
【図３８】後退したＡＦレンズ枠とＣＣＤホルダを斜め下方から見た斜視図である。
【図３９】ＣＣＤホルダ、ＡＦレンズ枠及び２群レンズ移動枠を正面から見た図である。
【図４０】２群レンズ枠がカム突起に当接する直前位置まで後退した状態を示す斜視図である。
【図４１】２群レンズ枠が退避位置に保持されて後方移動端まで後退した状態を示す斜視図である。
【図４２】露出制御ＦＰＣ基板の配設構造を示す断面図である。
【図４３】２群レンズ枠による露出制御ＦＰＣ基板の保持の態様を示す斜視図である。
【図４４】２群レンズ枠がＡＦレンズ枠に接近した状態を示す斜視図である。
【図４５】２群レンズ枠がＡＦレンズ枠に当て付く直前の状態を示す側面図である。
【図４６】２群レンズ枠がＡＦレンズ枠に当て付いた状態を示す側面図である。
【図４７】２群レンズ枠の移動軌跡とＡＦレンズ枠との位置関係を示す正面図である。
【図４８】２群レンズ移動枠を覆う第１外筒の斜視図である。
【図４９】同正面図である。
【図５０】第１と第２の偏心軸部材による第２レンズ群の光軸調整機構の異なる実施形態を示す正面図である。
【符号の説明】
ＬＧ１第１レンズ群（前方光学要素）
ＬＧ２第２レンズ群（退避光学要素）
ＬＧ３第３レンズ群（後方光学要素）
ＬＧ４ローパスフィルタ
Ｓシャッタ
Ａ絞り
Ｚ０鏡筒中心軸
Ｚ１撮影光軸
Ｚ２退避光軸
Ｚ３ファインダ対物系の光軸
ＰＸＰＹ１ＰＹ２調整軸
１１群レンズ枠
１ａ雄調整ねじ
１ｂ当付部
２１群調整環
２ａ雌調整ねじ
２ｂガイド突起
２ｃ係合爪
３１群抜止環
３ａばね受け部
６２群レンズ枠（揺動部材、被支持要素）
６ａレンズ筒
６ｂ揺動中心筒
６ｃ揺動アーム
６ｄ揺動軸孔
６ｅストッパアーム
６ｆ前方ばね支持部
６ｇ後方ばね支持部
６ｈ６ｉばね抜止突起
６ｊ退避作用アーム
６ｋ６ｐばね掛け孔
６ｍ後方突出部
６ｎＡＦ枠当接面
６ｑ直線支持面
６ｒ傾斜支持面
６ｓＦＰＣ支持突起部
８２群レンズ移動枠（直進進退環、支持体）
８ａ８ａ-Ｗ直進案内溝
８ｂ２群用カムフォロア
８ｂ-１前方カムフォロア
８ｂ-２後方カムフォロア
８ｃ前方支持板装着面（支持板固定手段）
８ｄ部分円筒状部
８ｅ後方支持板装着面（支持板固定手段）
８ｆ偏心軸支持孔
８ｇ揺動中心筒収納孔
８ｈビス挿通孔
８ｉ偏心軸支持孔
８ｊ前方ボス（移動ガイド手段、固定突起、突起）
８ｋ後方ボス（移動ガイド手段、固定突起、突起）
８ｍ回動規制ピン挿通孔
８ｎ貫通空間
８ｐキー溝
８ｑレンズ筒進入凹部
８ｒストッパアーム進入凹部
８ｓ中間フランジ部
８ｔ２群レンズ移動開口
９２群レンズ保持蓋
１０２群直進案内環
１０ａ股状突起
１０ｂリング部
１０ｃ１０ｃ-Ｗ直進案内キー
１０ｄＦＰＣ通し孔
１１カム環
１１ａ２群案内カム溝
１１ａ-１前方カム溝
１１ａ-２後方カム溝
１１ｂ１群案内カム溝
１１ｃ１１ｅ周方向溝
１１ｄバリヤ駆動環押圧面
１２第１外筒（外側筒）
１２ａ係合突起
１２ｂ１群調整環ガイド溝
１２ｃ内径フランジ
１２ｄドライバ挿通孔（第１または第２の回転操作孔）
１２ｅドライバ挿通孔（第３の回転操作孔）
１２ｆドライバ挿通孔（第４の回転操作孔）
１２ｇドライバ挿通孔（第１または第２の回転操作孔）
１３第２外筒
１３ａ直進案内突起
１３ｂ直進案内溝
１３ｃ内径フランジ
１４直進案内環
１４ａ直進案内突起
１４ｂ相対回動案内突起
１４ｃ相対回動案内突起
１４ｄ周方向溝
１４ｅローラ案内貫通溝
１４ｅ-１周方向溝部
１４ｅ-２周方向溝部
１４ｅ-３リード溝部
１４ｆ第１直進案内溝
１４ｇ第２直進案内溝
１５第３外筒
１５ａ回転伝達突起
１５ｂ嵌合突起
１５ｃばね当付凹部
１５ｄ相対回動案内突起
１５ｅ周方向溝
１５ｆローラ嵌合溝
１７ローラ付勢ばね
１７ａローラ押圧片
１８ヘリコイド環
１８ａ雄ヘリコイド
１８ｂ回転摺動突起
１８ｃスパーギヤ部
１８ｄ回転伝達凹部
１８ｅ嵌合凹部
１８ｆばね挿入凹部
１８ｇ周方向溝
２１ＣＣＤホルダ
２１ａカム突起（位置制御機構）
２１ｂ移動規制面
２１ｃ退避カム面
２１ｄ退避位置保持面
２１ｅガイドキー
２１ｆ退避方向斜面
２２固定環
２２ａ雌ヘリコイド
２２ｂ直進案内溝
２２ｃリード溝
２２ｄ回転摺動溝
２２ｅストッパ挿脱孔
２２ｆ環状部
２２ｇ２２ｈ切欠
２４１群付勢ばね
２５離間方向付勢ばね
２６鏡筒ストッパ
２８ズームギヤ
２９ズームギヤ軸
３０ファインダギヤ
３１１群用ローラ
３２カム環ローラ
３２ａローラ固定ねじ
３３２群回動軸（回動中心軸）
３３ａフランジ
３４Ｘ第１偏心軸部材（第１の偏心軸部材）
３４Ｘ-ａ大径軸部
３４Ｘ-ｂ前方偏心ピン
３４Ｘ-ｃ後方偏心ピン
３４Ｘ-ｄドライバ係合凹部（回転操作部）
３４Ｙ第２偏心軸部材（第２の偏心軸部材）
３４Ｙ-ａ大径軸部
３４Ｙ-ｂ前方偏心ピン
３４Ｙ-ｃ後方偏心ピン
３４Ｙ-ｄドライバ係合凹部（回転操作部）
３５回動規制ピン（位置制御機構、第３の偏心軸部材）
３５ａ大径軸部
３５ｂ偏心ピン
３５ｃドライバ係合凹部（回転操作部）
３６３７２群レンズ枠支持板（軸支持板、支持板）
３６ａ３７ａ第１縦長孔（第１の長孔）
３６ｂ３７ｂ回動軸嵌合孔
３６ｃ３７ｃカム突起挿脱開口
３６ｄ３７ｄビス螺合孔（支持板固定手段）
３６ｅ３７ｅ横長孔（第２の長孔）
３６ｆ３７ｆ第２縦長孔（移動ガイド手段、第３の長孔）
３６ｆ’ ３７ｆ’ 傾斜長孔（移動ガイド手段、第３の長孔）
３６ｇばね掛け部
３７ｇガイドキー進入溝
３８軸方向押圧ばね
３９２群レンズ枠戻しばね（位置制御機構）
３９ａ前方ばね端部
３９ｂ後方ばね端部
４０回転伝達ばね
４０ａ固定ばね端部
４０ｂ可動ばね端部
５１ＡＦレンズ枠（３群レンズ枠）
５１ａ５１ｂガイド孔
５１ｃ前方突出筒状部
５１ｃ１先端面
５１ｃ２開口部
５１ｃ３５１ｃ４５１ｃ５５１ｃ６側面
５１ｄ５１ｅガイド腕部
５１ｆ前方突出部
５１ｇ傾斜当接面
５１ｈ退避方向斜面
５２５３ＡＦガイド軸
５４ＡＦナット
５５ＡＦ枠付勢ばね
６０ＣＣＤ（固体撮像素子）
６１パッキン
６２ＣＣＤベース板
６４抜止環固定ビス
６６支持板固定ビス（支持板固定手段）
６６ａビス軸部
６６ｂドライバ係合凹部（回転操作部）
７０デジタルカメラ
７１ズームレンズ鏡筒
７２カメラボディ
７３フィルタホルダ
７４減速ギヤボックス
７５レンズ駆動制御ＦＰＣ基板
７６シャッタユニット
７７露出制御ＦＰＣ基板
７７ａ第１直線状部
７７ｂＵ字状部
７７ｃ第２直線状部
７７ｄ第３直線状部
８０ファインダユニット
８１ａ対物窓
８１ｂ８１ｃ可動変倍レンズ
８１ｄプリズム
８１ｅ接眼レンズ
８１ｆ接眼窓
８２ガイドシャフト
１０１バリヤカバー
１０２バリヤ押さえ板
１０３バリヤ駆動環
１０４１０５バリヤ羽根
１０６バリヤ付勢ばね
１０７バリヤ駆動環付勢ばね
１４０制御回路
１５０ズームモータ
１６０ＡＦモータ[0001]
【Technical field】
  The present invention relates to an optical element retracting mechanism for a lens barrel that retracts a part of a plurality of optical elements constituting a photographing optical system to a position different from a photographing optical axis position in a retracted state.The
[0002]
[Prior art and its problems]
  There is no need to reduce the size of the camera, and a storage type lens barrel that shortens the lens barrel during non-photographing is required to further reduce the storage length. To achieve this, the present applicant retracts some optical elements of the photographing optical system to a position different from the photographing optical axis when retracted, and retracts the retracting optical element backward along the optical axis together with other optical elements. Proposed a lens barrel (Japanese Patent No. 3771909). Such a mechanism for driving the retracting optical element that performs a complicated operation is required to have particularly high operation accuracy. In addition, it is required to be able to adjust the position of the retracting optical element with high accuracy with a simple structure.The
[0003]
[Patent Literature]
      Japanese Patent No. 3771909
[0004]
OBJECT OF THE INVENTION
  An object of the present invention is to provide an optical element retracting mechanism of a lens barrel capable of driving and adjusting the position of an optical element that is retracted and retracted to a position different from a photographing optical axis in a retracted state with high accuracy. TossThe
[0005]
SUMMARY OF THE INVENTION
  The present invention relates to a plurality of optical elements constituting an imaging optical system; a linear advancement / retraction ring that is guided linearly in the optical axis direction of the imaging optical system and retracts in the image plane direction when the imaging state is changed to the retracted state; A swinging member that supports a retracting optical element that forms a part of the element and is rotatably supported by a rotation center shaft provided inside a rectilinear advance / retreat ring; Is positioned on the same optical axis as the other optical element, and is rotated when the swinging member moves back and forth in the retracting direction together with the rectilinear advance and retreat, so that the retracting optical element is aligned with the optical axis of the other optical element. A position control mechanism for retracting to different positions; a pair of shaft support plates spaced apart in the optical axis direction supporting the front and rear end portions of the pivoting central axis of the swinging member by sandwiching a straight advancement / retraction ring from the front and rear; One where the shaft support plate is fixed to the rectilinear advance and retreat ring, and the direction perpendicular to the optical axis in the unlocked state A support plate fixing means that allows movement to the pair of shaft support plates, the pair of first long holes formed so that their long axes are parallel to each other, and the length of the first long holes A pair of second oblong holes having a major axis perpendicular to the axis;For the eccentric shaft support hole provided in the rectilinear advance / retreat ringRotating around an axis parallel to the optical axisInsertA first eccentric shaft member that has a pair of eccentric pins that are slidably engaged with the pair of first elongated holes, and a pair of second elongated holes that are slidably engaged. A second eccentric shaft member having a pair of eccentric pins at both ends; and a plane orthogonal to the optical axis when the first and second eccentric shaft members are provided on the pair of shaft support plates and the linear advance / retreat ring. Movement guide means for restricting the movement direction of each shaft support plate in the inside, wherein the first and second long holes in at least one of the shaft support plates are through-holes in the optical axis direction. Of the pair of eccentric pins at both ends of the eccentric shaft member and the pair of eccentric pins at both ends of the second eccentric shaft member, the opening on the side that engages with the through hole is opened from the front or rear opening of the straight advance / retreat ring A rotation operation unit capable of rotation operation is provided.
[0006]
The rotation operation portions of the first and second eccentric shaft members are preferably formed on the front eccentric pin side opposite to the storage direction. Further, in the case of having an outer cylinder that covers the outside of the rectilinear advance / retreat ring and has an inner diameter flange positioned in front of the rectilinear advance / retreat ring, the rotation of the first eccentric shaft member and the second eccentric shaft member on the inner diameter flange of the outer cylinder. It is preferable to form the first and second rotation operation holes that are located in front of the operation portion and penetrate in the optical axis direction, because each eccentric shaft member can be rotated without removing the outer cylinder.
[0007]
The support plate fixing means is constituted by a screw screw hole formed through the pair of shaft support plates in the optical axis direction and a common fixing screw simultaneously screwed into the screw screw hole, and then the fixing. The workability is further improved by setting the end portions of the screws facing the same direction as the rotation operation portions of the first and second eccentric shaft members as rotation operation portions. When the inner diameter flange of the outer cylinder is positioned in front of the rotation operation portion of the fixed screw, a third rotation operation hole for operating the fixed screw may be formed in the inner diameter flange.
[0008]
The rotation center axis of the swing member is preferably parallel to the optical axis of the photographing optical system. In this aspect, the position control mechanism of the swing member is further supported by a biasing means for biasing the swing member in the rotation direction, and a linearly advancing and retreating ring that is rotatable around a rotation center parallel to the optical axis. A third eccentric shaft member that determines an end of rotation in the biasing direction by engaging an eccentric pin that is eccentric to the swinging member is provided, and a third eccentric shaft member is provided separately from the first and second eccentric shaft members. A function of adjusting the position of the retracting optical element by rotating the eccentric shaft member may be provided. In this case, it is preferable that the third eccentric shaft member has a rotatory operation portion that can be rotated at an end portion facing in the same direction as the rotation operation portions of the first and second eccentric shaft members. . When the inner diameter flange of the outer cylinder is positioned in front of the rotation operation portion of the third eccentric shaft member, a fourth rotation operation hole for operating the third eccentric shaft member may be formed in the inner diameter flange. .
[0009]
It is preferable that a lens barrier mechanism is attached to and detached from the front portion of the inner diameter flange of the outer cylinder so that each of the rotation operation holes is covered by the lens barrier mechanism.
Further, it is preferable that the outer cylinder is a front optical element positioned in front of the retracting optical element, and is retracted together with the rectilinear advance / retreat ring during the storing operation from the photographing state.
[0010]
The eccentric shaft member and the rotation operation portion of the fixed screw can be, for example, a recess that can be engaged by the driver.
[0011]
The present invention has a rear optical element that is positioned behind the retracting optical element in the photographing state, and in the retracted state, the retracting optical element is positioned so as to overlap the rear optical element and the optical axis direction position. Suitable for cylinders.
[0012]
In the lens barrel of the present invention, the retracting optical element can be a lens group.
[0013]
  The lens barrel according to the present invention also includes a plurality of optical elements constituting the photographing optical system; linearly guided in the optical axis direction of the photographing optical system, and rectilinear advance / retreat which moves backward in the imaging plane direction from the photographing state to the retracted state. A pair of shaft support plates that are sandwiched from the front and rear and spaced apart in the optical axis direction, and a rotation center shaft whose both ends are supported by the pair of shaft support plates; A swinging member that supports a retracting optical element that is part of a plurality of optical elements and is pivotally supported by the pivot center axis; this swinging member is used as another retracting optical element in a photographing state. Are moved on the same optical axis and rotated when the swinging member moves back and forth in the storage direction along with the rectilinear advancement and retraction, and the retracting optical element is retracted to a position different from the optical axis of the other optical elements. Position control mechanism; the long axes of the pair of shaft support plates are parallel to each other Becomes so formed, a pair of first elongated hole, the second long hole before and after the pair having a long axis perpendicular to the long axis of the long hole of the first; respectivelyIs against the eccentric shaft support hole provided in the rectilinear advance and retreat ringRotating around an axis parallel to the optical axisInsertA first eccentric shaft member that has a pair of eccentric pins that are slidably engaged with the pair of first elongated holes, and a pair of second elongated holes that are slidably engaged. A second eccentric shaft member having a pair of eccentric pins at both ends; and a pair of shaft support plates that are threaded through and fixed in the optical axis direction and fixed to the rectilinear advance / retreat ring; A fixed screw that allows the pair of shaft support plates to move in a direction perpendicular to the optical axis in accordance with the rotation of the eccentric shaft member; and the front and rear of the first and second eccentric shaft members and the fixed screw are the same It is characterized in that the direction end portion can be rotated from the front or rear opening of the rectilinear advance / retreat ring.
[0014]
The pivot center axis of the swing member is preferably parallel to the optical axis of the photographic optical system. In this embodiment, the swing member further adjusts the position of the swing member separately from the first and second eccentric shaft members. 3 eccentric shaft members may be provided, and the third eccentric shaft member may be provided with a rotation operation portion that can be rotated from the same direction as the first and second eccentric shaft members.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
[Overall description of lens barrel]
First, the overall structure of the zoom lens barrel 71 of this embodiment will be described with reference to FIGS. This embodiment is an embodiment in which the present invention is applied to a zoom lens barrel for a digital camera 70. The photographing optical system includes a first lens group (front optical element) LG1, a shutter S, and an aperture in order from the object side. A, a second lens group (retracting optical element) LG2, a third lens group (rear optical element) LG3, a low-pass filter (filters) LG4, and a solid-state imaging device (hereinafter, CCD) 60. The optical axis of the photographing optical system is Z1. The photographing optical axis Z1 is parallel to the central axis Z0 of the zoom lens barrel 71 and is decentered with respect to the barrel central axis Z0. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 along a predetermined locus in the direction of the photographing optical axis Z1, and focusing is performed by moving the third lens group LG3 in the same direction. In the following description, “optical axis direction” means a direction parallel to the photographing optical axis Z1 unless otherwise specified.
[0017]
As shown in FIGS. 6 and 7, the fixed ring 22 is fixed in the camera body 72, and the CCD holder 21 is fixed to the rear part of the fixed ring 22. A CCD 60 is supported on the CCD holder 21 via a CCD base plate 62, and a low pass filter LG 4 is supported at the front of the CCD 60 via a filter holder 73 and a packing 61.
[0018]
An AF lens frame (third group lens frame) 51 that holds the third lens group LG3 is supported in the fixed ring 22 so as to be linearly movable in the optical axis direction. That is, the front end portion and the rear end portion of a pair of AF guide shafts 52 and 53 parallel to the photographing optical axis Z 1 are fixed to the fixed ring 22 and the CCD holder 21, respectively. The guide holes 51a and 51b formed in the AF lens frame 51 are slidably fitted. In the present embodiment, the AF guide shaft 52 is a main guide shaft, and the AF guide shaft 53 is provided for restricting the rotation of the AF lens frame 51. A feed screw formed on the drive shaft of the AF motor 160 is screwed into the AF nut 54 fixed to the AF lens frame 51. When the drive shaft is rotated, the screw screw and the AF nut 54 are screwed together. The AF lens frame 51 is advanced and retracted in the optical axis direction. The AF lens frame 51 is urged forward in the optical axis direction by an AF frame urging spring 55.
[0019]
As shown in FIG. 5, a zoom motor 150 and a reduction gear box 74 are supported on the upper portion of the fixed ring 22. The reduction gear box 74 has a reduction gear train inside, and transmits the driving force of the zoom motor 150 to the zoom gear 28. The zoom gear 28 is pivotally attached to the fixed ring 22 by a zoom gear shaft 29 parallel to the photographing optical axis Z1. The zoom motor 150 and the AF motor 160 are controlled by a camera control circuit 140 (FIG. 19) via a lens drive control FPC (flexible printed circuit) board 75 disposed on the outer peripheral surface of the fixed ring 22.
[0020]
On the inner peripheral surface of the fixed ring 22, a female helicoid 22a, three rectilinear guide grooves 22b parallel to the photographing optical axis Z1, three lead grooves 22c parallel to the female helicoid 22a, and the front end of each lead groove 22c A rotational sliding groove 22d is formed in the circumferential direction communicating with. The female helicoid 22a is not formed in a partial region of the front portion of the stationary ring 22 where the rotational sliding groove 22d is formed (see FIG. 8).
[0021]
The helicoid ring 18 has a male helicoid 18a threadedly engaged with the female helicoid 22a and a rotational sliding protrusion 18b engaged with the lead groove 22c and the rotational sliding groove 22d on the outer peripheral surface (FIGS. 4 and 9). ). A spur gear portion 18c having gear teeth parallel to the photographing optical axis Z1 is formed on the male helicoid 18a, and the spur gear portion 18c is screwed to the zoom gear 28. Accordingly, when a rotational force is applied by the zoom gear 28, the helicoid ring 18 advances and retracts in the direction of the optical axis while rotating in a state where the female helicoid 22a and the male helicoid 18a are in a screwed relationship, and moves forward to some extent when the male helicoid 18a Is disengaged from the female helicoid 22a, and only the circumferential rotation about the lens barrel center axis Z0 is performed by the engagement relationship between the rotational sliding groove 22d and the rotational sliding projection 18b. In the female helicoid 22a, the circumferential distance between a pair of helicoid mountains sandwiching each lead groove 22c is wider than the circumferential distance between other helicoid mountains, and the male helicoid 18a is a helicoid mountain with a wide circumferential distance. The three helicoid ridges 18a-W located behind the rotary sliding protrusion 18b are wider in the circumferential direction than the other helicoid ridges (FIGS. 8 and 9). The fixed ring 22 is formed with a stopper insertion / removal hole 22e penetrating the rotary sliding groove 22d and the outer peripheral surface, and the rotation of the helicoid ring 18 beyond the imaging region is restricted with respect to the stopper insertion / removal hole 22e. The lens barrel stopper 26 is detachable.
[0022]
A rotation transmission projection 15a (FIG. 11) projecting rearward from the rear end of the third outer cylinder 15 is fitted into a rotation transmission recess 18d (FIGS. 4 and 10) formed on the inner peripheral surface of the front end portion of the helicoid ring 18. Has been. The rotation transmission recesses 18d and the rotation transmission projections 15a are provided at three positions with different positions in the circumferential direction, and the rotation transmission projections 15a and the rotation transmission recesses 18d corresponding to the circumferential positions correspond to the central axis of the lens barrel. Relative sliding in the direction along Z0 is possible and coupled in a circumferential direction around the lens barrel central axis Z0 so that relative rotation is impossible. That is, the third outer cylinder 15 and the helicoid ring 18 rotate integrally. Further, the helicoid ring 18 is formed with a fitting recess 18e by notching a partial area on the inner diameter side of the rotary sliding projection 18b, and the fitting projection 15b fitted into the fitting recess 18e is rotated. When the sliding protrusion 18b engages with the rotational sliding groove 22d, it simultaneously engages with the rotational sliding groove 22d (see the upper half section of the zoom lens barrel in FIG. 6).
[0023]
Between the third outer cylinder 15 and the helicoid ring 18, there are provided three separation direction biasing springs 25 that bias each other in the separation direction on the extension of the optical axis. The separating-direction biasing spring 25 is a compression coil spring, and its rear end is housed in a spring insertion recess 18 f that opens at the front end of the helicoid ring 18, and its front end abuts against the spring contact recess 15 c of the third outer cylinder 15. It touches. The separation direction biasing spring 25 presses the fitting projection 15b toward the front side wall surface of the rotary sliding groove 22d and presses the rotary sliding projection 18b toward the rear side wall surface of the rotary sliding groove 22d. Thus, the backlash in the optical axis direction of the third outer cylinder 15 and the helicoid ring 18 with respect to the fixed ring 22 is removed.
[0024]
On the inner peripheral surface of the third outer cylinder 15, a relative rotation guide protrusion 15d projecting in the inner diameter direction, a circumferential groove 15e centering on the lens barrel central axis Z0, and 3 parallel to the photographing optical axis Z1 are provided. A roller fitting groove 15f is formed (FIGS. 4 and 11). A plurality of relative rotation guide protrusions 15d are provided at different positions in the circumferential direction. The roller fitting groove 15f is formed at a circumferential position corresponding to the rotation transmission protrusion 15a, and a rear end portion thereof is opened rearward through the rotation transmission protrusion 15a. Further, a circumferential groove 18g centering on the lens barrel central axis Z0 is formed on the inner peripheral surface of the helicoid ring 18 (FIGS. 4 and 10). A rectilinear guide ring 14 is supported inside the combined body of the third outer cylinder 15 and the helicoid ring 18. On the outer peripheral surface of the rectilinear guide ring 14, there are three rectilinear guide projections 14a projecting in the radial direction in order from the rear in the optical axis direction, and a plurality of relative rotation guide projections 14b provided in different positions in the circumferential direction. 14c and a circumferential groove 14d centering on the lens barrel central axis Z0 are formed (FIGS. 4 and 12). The rectilinear guide ring 14 is guided linearly in the optical axis direction with respect to the fixed ring 22 by engaging the rectilinear guide protrusion 14a with the rectilinear guide groove 22b. In addition, the third outer cylinder 15 has a circumferential groove 15e engaged with the relative rotation guide protrusion 14c and a relative rotation guide protrusion 15d engaged with the circumferential groove 14d, so that the third outer cylinder 15 is relative to the rectilinear guide ring 14. It is coupled to be rotatable. The circumferential grooves 15e and 14d and the relative rotation guide protrusions 14c and 15d are loosely fitted so as to be slightly movable in the optical axis direction. Further, the helicoid ring 18 is also coupled to the linear guide ring 14 so as to be relatively rotatable by engaging the circumferential groove 18g with the relative rotation guide protrusion 14b. The circumferential groove 18g and the relative rotation guide protrusion 14b are loosely fitted so as to be relatively movable in the optical axis direction.
[0025]
The linear guide ring 14 is formed with three roller guide through grooves 14e penetrating the inner peripheral surface and the outer peripheral surface. As shown in FIG. 12, each roller guide through-groove 14e has circumferential front and rear circumferential groove portions 14e-1 and 14e-2 formed in the circumferential direction, and both circumferential groove portions 14e-1 and 14e-2. Are connected to the female helicoid 22a and parallel to the lead groove 14e-3. A cam ring roller 32 provided on the outer peripheral surface of the cam ring 11 is fitted into each roller guide through groove 14e. The cam ring roller 32 is fixed to the cam ring 11 via a roller fixing screw 32a, and is provided with three different positions in the circumferential direction. The cam ring roller 32 further passes through the roller guide through groove 14e and is fitted into the roller fitting groove 15f on the inner peripheral surface of the third outer cylinder 15. Three roller pressing pieces 17a provided on the roller biasing spring 17 are fitted in the vicinity of the front end portion of each roller fitting groove 15f (FIG. 11). When the cam ring roller 32 engages with the circumferential groove portion 14e-1, the roller pressing piece 17a abuts against the cam ring roller 32 and presses backward, and the cam ring roller 32 and the roller guide through groove 14e (circumferential direction) Take backlash with the groove 14e-1).
[0026]
From the above structure, the mode of extension from the fixed ring 22 to the cam ring 11 is understood. In other words, when the zoom gear 28 is rotationally driven in the lens barrel feeding direction by the zoom motor 150, the helicoid ring 18 is fed forward while rotating due to the relationship between the female helicoid 22a and the male helicoid 18a. The helicoid ring 18 and the third outer cylinder 15 are rotatable and rotatable relative to the rectilinear guide ring 14 by the engagement relationship between the circumferential grooves 14d, 15e and 18g and the relative rotation guide protrusions 14b, 14c and 15d, respectively. Since they are coupled so as to move in the axial direction (the direction along the lens barrel central axis Z0), when the helicoid ring 18 is rotated out, the third outer cylinder 15 is also extended forward while rotating in the same direction. Accordingly, the rectilinear guide ring 14 moves straight forward together with the helicoid ring 18 and the third outer cylinder 15. Further, the rotational force of the third outer cylinder 15 is transmitted to the cam ring 11 via the roller fitting groove 15 f and the cam ring roller 32. Since the cam ring roller 32 is also fitted in the roller guide through groove 14e, the cam ring 11 is extended forward with respect to the linear guide ring 14 while rotating according to the shape of the lead groove 14e-3. As described above, the rectilinear guide ring 14 itself also moves straight forward together with the third outer cylinder 15 and the helicoid ring 18, and as a result, the cam ring 11 has a rotational advance according to the lead groove portion 14 e-3 and a rectilinear guide. An amount of movement in the optical axis direction is added to the amount of linear movement of the ring 14 forward.
[0027]
The above feeding operation is performed in a state where the male helicoid 18a is screwed with the female helicoid 22a. At this time, the rotary sliding protrusion 18b moves in the lead groove 22c. When the helicoid is fed out by a predetermined amount, the male helicoid 18a and the female helicoid 22a are unscrewed, and the rotary slide protrusion 18b eventually enters the rotary slide groove 22d from the lead groove 22c. At the same time, the cam ring roller 32 enters the circumferential groove 14e-1 of the roller guide through groove 14e. Then, since the helicoid ring 18 and the third outer cylinder 15 are not subjected to rotational output by the helicoid, the helicoid ring 18 and the third outer cylinder 15 only rotate at a fixed position in the optical axis direction according to the driving of the zoom gear 28. In this state, the linear guide ring 14 is stopped and the cam ring roller 32 is moved into the circumferential groove 14e-1, so that no forward moving force is applied to the cam ring 11, and the cam ring 11 is not connected to the third outer ring. According to the rotation of the cylinder 15, only rotation is performed at a fixed position.
[0028]
When the zoom gear 28 is rotationally driven in the lens barrel storage direction, the reverse operation is performed. When the helicoid ring 18 is rotated until the cam ring roller 32 enters the circumferential groove portion 14e-2 of the roller guide through groove 14e, each of the above-described lens barrel members retracts to the position shown in FIG.
[0029]
The structure ahead of the cam ring 11 will be further described. On the inner peripheral surface of the rectilinear guide ring 14, three first rectilinear guide grooves 14f and six second rectilinear guide grooves 14g parallel to the photographing optical axis Z1 are formed in different positions in the circumferential direction. . The first rectilinear guide groove 14f is composed of a pair of grooves located on both sides of the three second rectilinear guide grooves 14g out of the six, and the second group rectilinear guide ring 10 is in relation to the three first rectilinear guide grooves 14f. Three crotch-shaped projections 10a (FIGS. 3 and 15) provided in the slidably engage with each other. On the other hand, six rectilinear guide protrusions 13a (FIGS. 2 and 17) projecting from the outer peripheral surface of the rear end portion of the second outer cylinder 13 are slidably engaged with the second rectilinear guide groove 14g. Yes. Therefore, both the second outer cylinder 13 and the second group rectilinear guide ring 10 are guided in the straight direction in the optical axis direction via the rectilinear guide ring 14.
[0030]
The second group rectilinear guide ring 10 is a member for guiding the second group lens moving frame (linear advance / retract ring, support) 8 that supports the second lens group LG2 so that the second outer cylinder 13 is the first lens. This is a member for linearly guiding the first outer cylinder (outer cylinder) 12 that supports the group LG1.
[0031]
First, the support structure of the second lens group LG2 will be described. The second group rectilinear guide ring 10 has three rectilinear guide keys 10c projecting forward from a ring portion 10b connecting the three crotch protrusions 10a (FIGS. 3 and 15). As shown in FIGS. 6 and 7, the outer edge portion of the ring portion 10b can rotate relative to the circumferential groove 11e formed on the inner peripheral surface of the rear end portion of the cam ring 11, and cannot move relative to the optical axis. The linear guide key 10 c is engaged and extends inside the cam ring 11. Each rectilinear guide key 10c has a pair of guide surfaces parallel to the photographic optical axis Z1 on its side surface, and these guide surfaces are rectilinear guide grooves of the second group lens moving frame 8 supported inside the cam ring 11. By engaging with 8a, the second group lens moving frame 8 is guided straight in the axial direction. The rectilinear guide groove 8 a is formed on the outer peripheral surface side of the second group lens moving frame 8.
[0032]
A second group guide cam groove 11 a is formed on the inner peripheral surface of the cam ring 11. As shown in FIG. 14, the second group guide cam groove 11a is composed of a front cam groove 11a-1 and a rear cam groove 11a-2 whose positions are different in the optical axis direction and the circumferential direction. Both the front cam groove 11a-1 and the rear cam groove 11a-2 are cam grooves formed by tracing the basic trajectory α of the same shape, but each does not cover the entire area of the basic trajectory α. The front cam groove 11a-1 and the rear cam groove 11a-2 are different from each other in the area occupied on the basic locus α. The basic trajectory is a conceptual cam groove shape including all lens barrel use areas (use areas) including a zoom area and a storage area, and an assembly / disassembly area of the lens barrel. In other words, the lens barrel use area is an area in which movement can be controlled by the cam mechanism, and is used to distinguish from the assembly / disassembly area of the cam mechanism. The zoom area is an area for controlling the movement between the wide end and the tele end in the lens barrel use area, and is used to distinguish it from the storage area. When the cam ring 11 includes a pair of the front cam groove 11a-1 and the rear cam groove 11a-2, three groups of two-group guide cam grooves 11a are formed at equal intervals in the circumferential direction.
[0033]
A second group cam follower 8b provided on the outer peripheral surface of the second group lens moving frame 8 is engaged with the second group guide cam groove 11a. Similar to the second group guide cam groove 11a, the second group cam follower 8b is also equally spaced in the circumferential direction with a pair of front cam follower 8b-1 and rear cam follower 8b-2 having different positions in the optical axis direction and circumferential direction as one group. The front cam followers 8b-1 are engaged with the front cam grooves 11a-1, and the rear cam followers 8b-2 are engaged with the rear cam grooves 11a-2 in the optical axis direction. A circumferential interval is defined.
[0034]
Since the second group lens moving frame 8 is linearly guided in the optical axis direction via the second group linear guide ring 10, when the cam ring 11 rotates, the second group lens moving frame 8 becomes light according to the second group guide cam groove 11a. Move in the axial direction with a predetermined trajectory.
[0035]
Inside the second group lens moving frame 8, a second group lens frame (swing member, supported element) 6 that holds the second lens group LG2 is supported. The second group lens frame 6 is pivotally supported via a second group rotation shaft (rotation center axis) 33 with respect to a pair of second group lens frame support plates (shaft support plates, support plates) 36, 37. The second group frame support plates 36 and 37 are fixed to the second group lens moving frame 8 by support plate fixing screws (support plate fixing means) 66. The second group rotation shaft 33 is parallel to the photographing optical axis Z1 and is eccentric with respect to the photographing optical axis Z1, and the second group lens frame 6 has the second group rotation shaft 33 as the rotation center, and the second lens group LG2. And a retracting position for storage (FIG. 7) in which the optical axis of the second lens group LG2 is decentered from the capturing optical axis Z1 and the retracting optical axis Z2 is aligned with the capturing optical axis Z1. And can be rotated. The second group lens moving frame 8 is provided with a rotation restricting pin (position control mechanism, third eccentric shaft member) 35 for restricting the second group lens frame 6 from rotating at the photographing position. The frame 6 is urged to rotate in a contact direction with the rotation restricting pin 35 by a second group lens frame return spring (position control mechanism) 39. The axial pressing spring 38 performs backlash removal in the optical axis direction of the second group lens frame 6.
[0036]
The second group lens frame 6 moves integrally with the second group lens moving frame 8 in the optical axis direction. The CCD holder 21 has a cam projection (position control mechanism) 21a (FIG. 4) projecting forward at a position engageable with the second group lens frame 6, as shown in FIG. When 8 moves in the storing direction and approaches the CCD holder 21, the cam surface formed at the tip of the cam projection 21a engages with the second group lens frame 6 and rotates to the storing retracted position. This two-group retraction structure will be described later.
[0037]
Next, a support structure for the first lens group LG1 will be described. Three rectilinear guide grooves 13b are formed in the optical axis direction on the inner peripheral surface of the second outer cylinder 13 that is guided linearly in the optical axis direction via the rectilinear guide ring 14. In addition, three engagement protrusions 12a formed on the outer peripheral surface near the rear end portion of the first outer cylinder 12 are slidably fitted in each of the straight guide grooves 13b (FIGS. 2, 17, and 18). reference). That is, the first outer cylinder 12 is guided in a straight line in the optical axis direction via the straight guide ring 14 and the second outer cylinder 13. The second outer cylinder 13 has an inner diameter flange 13 c directed in the circumferential direction on the inner peripheral surface near the rear end portion, and the inner diameter flange 13 c slides in a circumferential groove 11 c provided on the outer peripheral surface of the cam ring 11. By engaging with each other, the second outer cylinder 13 is coupled to the cam ring 11 so as to be rotatable relative to the cam ring 11 but not movable relative to the optical axis. On the other hand, the first outer cylinder 12 has three first group rollers (cam followers) 31 projecting in the inner diameter direction, and each of the first group rollers 31 is formed on the outer peripheral surface of the cam ring 11. The guide cam groove 11b is slidably fitted.
[0038]
The first group lens frame 1 is supported in the first outer cylinder 12 via the first group adjustment ring 2. The first lens group LG1 is fixed to the first group lens frame 1, and the male adjustment screw 1a formed on the outer peripheral surface thereof is screwed with the female adjustment screw 2a formed on the inner peripheral surface of the first group adjustment ring 2. . By adjusting the screwing position of the adjusting screw, the position of the first group lens frame 1 can be adjusted in the optical axis direction with respect to the first group adjusting ring 2.
[0039]
The first group adjusting ring 2 has a pair of guide protrusions 2b (only one is shown in FIG. 2) protruding in the outer diameter direction, and the pair of guide protrusions 2b is on the inner peripheral surface side of the first outer cylinder 12. Are slidably engaged with a pair of first-group adjustment ring guide grooves 12b. The first group adjustment ring guide groove 12b is formed in parallel with the photographic optical axis Z1, and the first group adjustment ring 2 and the first group lens frame 1 are arranged according to the engagement relationship between the first group adjustment ring guide groove 12b and the guide projection 2b. The combined body can be moved back and forth in the optical axis direction with respect to the first outer cylinder 12. Further, the first group retaining ring 3 is fixed to the first outer cylinder 12 by a retaining ring fixing screw 64 so as to block the front of the guide protrusion 2b. Between the spring receiving portion 3a of the first group retaining ring 3 and the guide projection 2b, a first group biasing spring 24 made of a compression coil spring is provided, and the first group adjusting ring 2 causes the first group adjusting ring 2 to light. It is biased axially rearward. The first group adjusting ring 2 is engaged with the front surface of the first group retaining ring 3 (the surface on the side visible in FIG. 2) by engaging an engaging claw 2c projecting on the outer peripheral surface near the front end thereof. The maximum position of the rearward movement in the optical axis direction relative to the outer cylinder 12 is regulated (see the upper half section in FIG. 6). On the other hand, by compressing the first group biasing spring 24, the first group adjusting ring 2 can move a little forward in the optical axis direction.
[0040]
A shutter unit 76 having a shutter S and an aperture A is supported between the first lens group LG1 and the second lens group LG2. The shutter unit 76 is supported on the inner side of the second group lens moving frame 8, and the air distance between the shutter S and the aperture stop A between the second lens group LG2 is fixed. Two actuators (not shown) for driving the shutter S and the diaphragm A are arranged one by one at the front and rear positions with the shutter unit 76 in between, and these actuators are arranged from the shutter unit 76 to the control circuit 140 of the camera. An exposure control FPC (flexible printed circuit) board 77 is connected to the terminal.
[0041]
In addition to the shutter S, a lens barrier mechanism is provided at the front end of the first outer cylinder 12 to close the photographing aperture and protect the photographing optical system (first lens group LG1) when not photographing. The lens barrier mechanism includes a pair of barrier blades 104 and 105 that are rotatable about a rotation shaft provided at a position eccentric with respect to the lens barrel central axis Z0, and urges the barrier blades 104 and 105 in the closing direction. A pair of barrier urging springs 106, a barrier drive ring 103 that can be rotated about the central axis Z0 of the barrel, and engage with the barrier blades 104 and 105 by rotation in a predetermined direction, and the barrier drive ring 103 A barrier drive ring biasing spring 107 that biases 103 in the barrier opening direction and a barrier pressing plate 102 positioned between the barrier blades 104 and 105 and the barrier drive ring 103 are provided. The urging force of the barrier drive ring urging spring 107 is set to be stronger than the urging force of the barrier urging spring 106, and when the zoom lens barrel 71 is extended to the zoom region (FIG. 6), the barrier driving ring is attached. The biasing spring 107 holds the barrier driving ring 103 at the angular position for opening the barrier, and the barrier blades 104 and 105 are opened against the barrier biasing spring 106. During the movement of the zoom lens barrel 71 from the zoom region to the storage position (FIG. 7), the barrier drive ring pressing surface 11d (FIGS. 3 and 13) of the cam ring 11 opposes the barrier drive ring 103 in the barrier opening direction. The barrier driving ring 103 is disengaged from the barrier blades 104 and 105, and the barrier blades 104 and 105 are closed by the biasing force of the barrier biasing spring 106. The front part of the lens barrier mechanism is covered with a barrier cover 101 (decorative plate).
[0042]
The overall feeding and storing operation of the zoom lens barrel 71 having the above structure will be described with reference to FIGS. FIG. 19 conceptually shows the relationship between the main members of the zoom lens barrel 71. “S” in parentheses after the reference numeral of each member is a fixed member, and “L” is in the optical axis direction. A member that performs only linear movement, “R” indicates a member that performs only rotation, and “RL” indicates a member that moves in the optical axis direction while rotating. Moreover, the member in which two symbols are written in parentheses means that the operation mode is switched during feeding and storage.
[0043]
Since the cam ring 11 has already been described up to the stage where the cam ring 11 is extended from the storage position to the fixed position rotation state, a brief description will be given. 7, the zoom lens barrel 71 is completely stored in the camera body 72, and the front surface of the camera body 72 has a flat shape from which the zoom lens barrel 71 does not protrude. When the zoom gear 28 is driven to rotate in the extending direction by the zoom motor 150 from the lens barrel storage state, the combined body of the helicoid ring 18 and the third outer cylinder 15 is rotated and extended according to the helicoid (male helicoid 18a, female helicoid 22a). The straight guide ring 14 moves straight forward together with the third outer cylinder 15 and the helicoid ring 18. At this time, the cam ring 11 to which the rotational force is applied by the third outer cylinder 15 is a lead structure (cam ring roller) provided between the linear movement of the linear guide ring 14 and the linear guide ring 14. 32, the combined movement with the feeding portion by the lead groove 14e-3) is performed. When the helicoid ring 18 and the cam ring 11 are drawn out to a predetermined position in front, the functions of the respective rotary feeding structures (helicoid, lead) are canceled and only the circumferential rotation about the lens barrel central axis Z0 is performed. become.
[0044]
When the cam ring 11 rotates, on the inner side, the second group lens moving frame 8 guided linearly through the second group linear guide ring 10 is in the optical axis direction due to the relationship between the second group cam follower 8b and the second group guide cam groove 11a. Is moved along a predetermined trajectory. In the lens barrel storage state of FIG. 7, the second group lens frame 6 in the second group lens moving frame 8 is held at the storage retracted position on the upper side of the AF lens frame 51 by the action of the cam projection 21 a protruding from the CCD holder 21. Thus, the second lens group LG2 is retracted from the photographing optical axis Z1. The second group lens frame 6 is separated from the cam projection 21a while the second group lens moving frame 8 is extended from the storage position to the zoom region, and the optical axis of the second lens group LG2 by the urging force of the second group lens frame return spring 39. Is rotated to a photographing position (FIG. 6) that coincides with the photographing optical axis Z1. Thereafter, the second group lens frame 6 is held at the photographing position until the zoom lens barrel 71 is moved again to the storage position.
[0045]
Further, when the cam ring 11 rotates, the first outer cylinder 12 guided linearly through the second outer cylinder 13 on the outside of the cam ring 11 is related to the first group roller 31 and the first group guide cam groove 11b. Is moved along a predetermined locus in the optical axis direction.
[0046]
That is, the first lens group LG1 and the second lens group LG2 are extended with respect to the imaging surface (CCD light receiving surface), respectively, with the former moving amount of the cam ring 11 with respect to the fixed ring 22 and the first moving position with respect to the cam ring 11 respectively. It is determined as a total value of the cam feed amount of the outer cylinder 12, and the latter is a sum value of the forward movement amount of the cam ring 11 with respect to the fixed ring 22 and the cam feed amount of the second group lens moving frame 8 with respect to the cam ring 11. Determined. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 on the photographing optical axis Z1 while changing the air interval between them. When the lens barrel is extended from the storage position of FIG. 7, first, the wide end extended state shown in the lower half cross section of FIG. 6 is obtained, and when the zoom motor 150 is further driven in the lens barrel extending direction, the upper half cross section of FIG. As shown in FIG. As can be seen from FIG. 6, in the zoom lens barrel 71 of the present embodiment, the distance between the first lens group LG1 and the second lens group LG2 is large at the wide end, and the first lens group LG1 and the second lens at the tele end. The group LG2 moves in the direction of mutual approach, and the interval is reduced. Such a change in the air gap between the first lens group LG1 and the second lens group LG2 is given by the locus of the second group guide cam groove 11a and the first group guide cam groove 11b. In the zoom region (zooming use region) between the tele end and the wide end, the cam ring 11, the third outer cylinder 15, and the helicoid ring 18 perform only the above-mentioned fixed position rotation and do not advance or retreat in the optical axis direction.
[0047]
In the zoom region, by driving the AF motor 160 according to the subject distance, the third lens group LG3 (AF lens frame 51) moves along the photographing optical axis Z1 to perform focusing.
[0048]
When the zoom motor 150 is driven in the lens barrel storage direction, the zoom lens barrel 71 performs a storage operation opposite to that at the time of the above-described extension, so that the storage position is completely stored in the camera body 72 (FIG. 7). Moved to. In the middle of the movement to the storage position, the second group lens frame 6 is rotated to the storage retreat position by the cam projection 21 a and retracts together with the second group lens movement frame 8. When the zoom lens barrel 71 is moved to the storage position, the second lens group LG2 is stored at the same position as the third lens group LG3 and the low-pass filter LG4 in the optical axis direction (overlapping in the radial direction of the lens barrel). . Due to the retracting structure of the second lens group LG2 during storage, the storage length of the zoom lens barrel 71 is shortened, and the thickness of the camera body 72 in the left-right direction in FIG. 7 can be reduced.
[0049]
The digital camera 70 includes a zoom finder that is linked to the zoom lens barrel 71. The zoom finder meshes the finder gear 30 with the spur gear portion 18c to obtain power from the helicoid ring 18, and when the helicoid ring 18 performs the above-mentioned fixed position rotation in the zoom region, the finder gear receives the rotational force. 30 rotates. The finder optical system includes an objective window 81a, a first movable variable lens 81b, a second movable variable lens 81c, a prism 81d, an eyepiece lens 81e, and an eyepiece window 81f, and first and second movable variable magnifications. Zooming is performed by moving the lenses 81b and 81c along a predetermined locus along the optical axis Z3 of the finder objective system. The optical axis Z3 of the finder objective system is parallel to the photographing optical axis Z1. The holding frames of the movable zoom lenses 81b and 81c are guided by a guide shaft 82 so as to be movable in the direction of the optical axis Z3, and receive a driving force from a shaft screw parallel to the guide shaft 82. A reduction gear train is provided between the shaft screw and the finder gear 30. When the finder gear 30 rotates, the shaft screw rotates, and the movable zoom lenses 81b and 81c advance and retract. The above components of the zoom finder are sub-assembled as a finder unit 80 shown in FIG.
[0050]
[Description of lens barrel storage structure]
Next, details of the housing structure of the zoom lens barrel 71 including the retracting structure of the second lens group LG2 will be described. In the following description, the vertical (vertical) direction and the horizontal (horizontal) direction correspond to the vertical and horizontal directions viewed from the front or back of the camera as shown in FIGS. The front-rear direction is a direction parallel to the optical axis. Moreover, in order to make it easy to identify a member, in some drawings, the thickness of the outline line is different for each member, and the line type is different.
[0051]
The second lens group LG2 is supported on the second group lens moving frame 8 by each member shown in FIG. The second group lens frame 6 includes a lens tube 6a that supports the second lens group LG2, a swing arm 6c that extends in the radial direction of the lens tube 6a, a swing center tube 6b provided at the tip of the swing arm 6c, and It has a stopper arm 6e extending from the lens tube 6a in a radial direction different from that of the swing arm 6c. The swing center tube 6b is formed with a swing shaft hole 6d penetrating in a direction parallel to the optical axis of the second lens group LG2. A front spring support portion 6f and a rear spring support portion 6g each having a cylindrical outer peripheral surface are formed in the swing center tube 6b at front and rear positions in the optical axis direction across the connection portion with the swing arm 6c. On the outer peripheral surface in the vicinity of the front end portion of the front spring support portion 6f and in the vicinity of the rear end portion of the rear spring support portion 6g, spring retaining protrusions 6h and 6i are projected. A retracting action arm 6j extends from the swinging center tube 6b in a direction different from that of the swinging arm 6c, and a spring hooking hole 6k is formed in the retracting action arm 6j. The swing arm 6c has a spring hook hole 6p. The spring hooking hole 6k and the spring hooking hole 6p are shown in FIGS.
[0052]
A rearward protruding portion 6m protrudes from the swing arm 6c toward the rear of the optical axis, and a flat AF frame contact surface perpendicular to the optical axis of the second lens group LG2 is provided at the tip of the rearward protruding portion 6m. 6n is formed. As shown in FIG. 45 and FIG. 46, a second group lens holding lid 9 for securing the second lens group LG2 is fixed to the rear end portion of the lens cylinder 6a. It is located behind the second group lens holding lid 9 in the optical axis direction. That is, the AF frame contact surface 6n is located behind the rearmost part of the second lens group LG2 in the optical axis direction.
[0053]
The second group lens frame support plate 36 is an elongated plate-like member that is long in the up-down direction and narrow in the left-right direction, and in order from the top in the longitudinal direction, a first vertical hole (first long hole) 36a, Rotating shaft fitting hole 36b, cam projection insertion / removal opening 36c, screw screwing hole (support plate fixing means) 36d, laterally elongated hole (second elongated hole) 36e, and second vertically elongated hole (moving guide means, third A long hole 36f is formed. Each of these holes is a through-hole penetrating the front and back of the second group lens frame support plate 36. On the outer periphery of the second group lens frame support plate 36, a concave spring hook 36g is formed.
[0054]
The second group lens frame support plate 37 is an elongated plate-like member having substantially the same shape as the second group lens frame support plate 36, and in order from the top in the longitudinal direction, the first vertical hole (first long hole). 37a, rotation shaft fitting hole 37b, cam projection insertion / removal opening 37c, screw screwing hole (support plate fixing means) 37d, laterally elongated hole (second elongated hole) 37e and second vertically elongated hole (moving guide means, first guide) 3 long holes) 37f are formed. Each of these holes is a through-hole penetrating the front and back of the second group lens frame support plate 37. Further, a guide key entry groove 37g is formed in the cam protrusion insertion / removal opening 37c by cutting out a part of its inner edge.
[0055]
Screw screw holes 36d and 37d provided in the front and rear second group lens frame support plates 36 and 37 are screw holes having the same diameter, and a screw shaft portion 66a of the support plate fixing screw 66 can be screwed therein. One end portion of the screw shaft portion 66a has a driver engagement recess (rotation operation portion) 66b for engaging a driver (adjustment tool).
[0056]
The first eccentric shaft member (first eccentric shaft member) 34X has a pair of front eccentric pins 34X-b and rear eccentric pins 34X-c at front and rear end portions sandwiching the large-diameter shaft portion 34X-a. . The front eccentric pin 34X-b and the rear eccentric pin 34X-c are formed so as to be eccentric with respect to the central axis of the large-diameter shaft portion 34X-a and have the same diameter. A driver engagement recess (rotation operation portion) 34X-d for engaging a driver (adjustment tool) is formed at the end of the front eccentric pin 34X-b. The second eccentric shaft member (second eccentric shaft member) 34Y has the same structure as the first eccentric shaft member 34X. That is, the front and rear end portions sandwiching the large-diameter shaft portion 34Y-a have a pair of front eccentric pins 34Y-b and rear eccentric pins 34Y-c. The front eccentric pins 34Y-b and the rear eccentric pins 34Y-c are: The large-diameter shaft portion 34Y-a is formed so as to be eccentric with respect to the central axis and have the same diameter. A driver engagement recess (rotation operation portion) 34Y-d for engaging a driver (adjustment tool) is formed at the end of the front eccentric pin 34Y-b.
[0057]
A spring housing hole (not shown) having an inner diameter larger than that of the rear spring support portion 6g is formed in the rear spring support portion 6g of the second group lens frame 6 so as to communicate with the swing shaft hole 6d. The axial pressing spring 38 can be stored in the storage hole. The axial pressing spring 38 is a compression coil spring. Each of the second group lens frame return spring 39 and the rotation transmission spring 40 is a torsion spring, and the second group lens frame return spring 39 can be mounted on the outer peripheral surface of the front spring support portion 6f of the second group lens frame 6 to rotate. The transmission spring 40 can be mounted on the outer peripheral surface of the rear spring support 6g. The second group lens frame return spring 39 has a front spring end 39a and a rear spring end 39b extending in the front-rear direction, and the rotation transmission spring 40 includes a fixed spring end 40a protruding in the radial direction. And a movable spring end 40b.
[0058]
The second group rotation shaft 33 has a diameter that can be relatively rotated with respect to the swinging shaft hole 6d of the second group lens frame 6 and fits in the radial direction without looseness, and the outer diameter size of both ends thereof is the second group lens frame. This corresponds to the inner diameter size of the rotation shaft fitting hole 36b of the support plate 36 and the rotation shaft fitting hole 37b of the second group lens frame support plate 37. The axis of the second group rotation shaft 33 inserted into the swing shaft hole 6d is parallel to the optical axis of the second lens group LG2. The second group rotating shaft 33 also has a flange 33a in the vicinity of the end on the rear side in the optical axis direction, and the flange 33a enters into a spring accommodation hole (not shown) of the rear spring support portion 6g and is axially pressed. It can abut against the spring 38.
[0059]
The inside of the second group lens moving frame 8 having a single shape shown in FIGS. 24 and 25 is a through space 8n penetrating in the optical axis direction, and an intermediate flange portion located substantially at the center in the optical axis direction of the through space 8n. In 8s, a two-group lens moving aperture 8t having a vertically long shape in the vertical direction is formed. The shutter unit 76 is fixed to the front side of the intermediate flange portion 8s. In addition, a lens tube entry recess 8q corresponding to the outer edge shape of the lens tube 6a and a stopper arm entry recess 8r corresponding to the outer edge shape of the stopper arm 6e are formed on the inner peripheral surface behind the intermediate flange portion 8s. (See FIG. 29).
[0060]
As shown in FIGS. 24 and 25, the second group lens moving frame 8 is viewed from the front, the right side of the second group lens moving aperture 8t is not overlapped with the second group lens moving aperture 8t, and the optical axis An orthogonal flat front support plate mounting surface (support plate fixing means) 8c is formed. The front support plate mounting surface 8c is a hatched region in FIGS. 24 and 25, and is positioned in front of the intermediate flange portion 8s and the shutter unit 76 attached to the front surface of the intermediate flange portion 8s. The front support plate mounting surface 8c is a surface exposed to the front of the second group lens moving frame 8, and the second group lens moving frame 8 has three partial cylinders protruding forward from the front support plate mounting surface 8c. 8d is formed, and a front cam follower 8b-1 is provided on the outer peripheral surface of each partial cylindrical portion 8d. On the other hand, a flat rear support plate mounting surface (support plate fixing means) 8e parallel to the front support plate mounting surface 8c is formed behind the front support plate mounting surface 8c across the two intermediate flange portions 8s. The rear support plate mounting surface 8e is flush with the rear end surface of the second group lens moving frame 8.
[0061]
The second group lens moving frame 8 is formed with an eccentric shaft support hole 8f, a swinging center tube storage hole 8g, a screw insertion hole 8h, and an eccentric shaft support hole 8i in order from the upper side. Passes through the front support plate mounting surface 8c and the rear support plate mounting surface 8e toward the optical axis direction. Further, a key groove 8p parallel to the optical axis is formed on the inner wall surface of the swing center tube storage hole 8g. The key groove 8p also penetrates the front support plate mounting surface 8c and the rear support plate mounting surface 8e. Yes. The upper eccentric shaft support hole 8f is formed to have an inner diameter size that rotatably supports the large-diameter shaft portion 34X-a of the first eccentric shaft member 34X, and the lower eccentric shaft support hole 8i is the second eccentric shaft support hole 8i. The large diameter shaft portion 34Y-a of the shaft member 34Y is formed to have an inner diameter size that rotatably supports the shaft member 34Y (see FIG. 31). On the other hand, the inner diameter size of the screw insertion hole 8h is formed large so that a considerable gap is formed between the screw shaft portion 66a of the support plate fixing screw 66 (see FIG. 31). Further, the front support plate mounting surface 8c and the rear support plate mounting surface 8e have a front boss (movement guide means, fixed protrusion, protrusion) 8j and a rear boss (movement guide means, fixed) that are concentric and have the same diameter. (Protrusions, protrusions) 8k are projected. The second group lens moving frame 8 is further formed with a rotation restricting pin insertion hole 8m penetrating the intermediate flange portion 8s in the front-rear direction at a position below the second group lens moving opening 8t.
[0062]
The rotation restricting pin 35 has an eccentric pin 35b eccentric to the large diameter shaft portion 35a at one end of the large diameter shaft portion 35a that is rotatably inserted into the rotation restricting pin insertion hole 8m. The other end portion has a driver engagement recess (rotation operation portion) 35c for engaging a driver (adjustment tool).
[0063]
A state in which the above elements are combined is shown in FIGS. Assembly is performed as follows. First, the second group lens frame return spring 39 and the rotation transmission spring 40 are attached to the second group lens frame 6. The second group lens frame return spring 39 has a coiled portion attached to the outer peripheral surface of the front spring support portion 6f of the swing center tube 6b, and a rear spring end 39b near the boundary between the swing center tube 6b and the swing arm 6c. (Fig. 22). The front spring end 39 a of the second group lens frame return spring 39 is not engaged with the second group lens frame 6. The rotation transmitting spring 40 has a coil-like portion attached to the outer peripheral surface of the rear spring support portion 6g of the swinging center tube 6b, and one fixed spring end portion 40a is inserted into the spring hooking hole 6p of the swinging arm 6c. The movable spring end 40b is inserted into the spring hooking hole 6k of the retracting arm 6j. The fixed spring end portion 40a is fixed to the spring hooking hole 6p, and the movable spring end portion 40b is allowed to move θ1 shown in FIG. 37 in the direction of moving toward and away from the fixed spring end portion 40a within the spring hooking hole 6k. . In a state where no external force is applied, the rotation transmission spring 40 is supported by the second group lens frame 6 in a state where it is slightly bent in the direction in which the fixed spring ends 40a and 40b approach each other. The part 40b comes into contact with one wall surface in the spring hooking hole 6k (FIG. 37). The second group lens frame return spring 39 and the rotation transmission spring 40 are prevented from coming off in the optical axis direction by the front and rear spring retaining projections 6h and 6i.
[0064]
Apart from the mounting of the second group lens frame return spring 39 and the rotation transmission spring 40, the second group rotation shaft 33 is inserted after the axial pressing spring 38 is inserted into a spring accommodation hole (not shown) in the rear spring support 6g. Is inserted into the swing shaft hole 6d. The flange 33a of the second group rotating shaft 33 enters the rear spring support 6g and abuts against the axial pressing spring 38. The axial length of the second group rotating shaft 33 is longer than the axial length of the swinging central cylinder 6b, and both end portions of the second group rotating shaft 33 protrude forward and backward from the swinging central cylinder 6b.
[0065]
In parallel with the attachment of the above-described members to the swing center tube 6b, the first eccentric shaft member 34X and the second eccentric shaft member 34Y are respectively connected to the eccentric shaft support hole 8f and the eccentric shaft support hole 8i of the second group lens moving frame 8. Insert it in. Each of the first eccentric shaft member 34X and the second eccentric shaft member 34Y has a large-diameter portion of the front end side of the large-diameter shaft portion 34X-a and the large-diameter shaft portion 34Y-a that has a larger diameter than the other regions. Correspondingly, the eccentric shaft support hole 8f and the eccentric shaft support hole 8i also have an inner diameter size in a part of the area in front of the optical axis direction larger than the inner diameter size of the other areas (see FIG. 31). Therefore, when the first eccentric shaft member 34X and the second eccentric shaft member 34Y are inserted from the front in the optical axis direction into the eccentric shaft support hole 8f and the eccentric shaft support hole 8i, respectively, the eccentric shaft support holes 8f and 8i. The insertion is restricted when the large-diameter portions of the large-diameter shaft portions 34X-a and 34Y-a abut on the step portion having the inner diameter size (position in FIG. 31). In this state, the front eccentric pin 34X-b and the front eccentric pin 34Y-b protrude from the front support plate mounting surface 8c, and the rear eccentric pin 34X-c and the rear eccentric pin 34Y-c protrude from the rear support plate mounting surface 8e. .
[0066]
Subsequently, the front end portion of the second group rotating shaft 33 protruding from the swinging center tube 6b is inserted into the rotating shaft fitting hole 36b, and the rear end portion is inserted into the rotating shaft fitting hole 37b while supporting the front. The second group lens frame support plate 36 and the second group lens frame support plate 37 are attached to the second group lens moving frame 8 so as to sandwich the plate mounting surface 8c and the rear support plate mounting surface 8e from the front and rear. At this time, three front eccentric pins 34X-b projecting from the front support plate mounting surface 8c with respect to the first vertically long hole 36a, the horizontally long hole 36e, and the second vertically long hole 36f of the front second group lens frame support plate 36, The front eccentric pin 34Y-b and the front boss 8j are engaged with each other. Further, three rear eccentric pins 34X-c projecting from the rear support plate mounting surface 8e with respect to the first vertically long hole 37a, the laterally long hole 37e and the second vertically long hole 37f of the rear two-group lens frame support plate 37, The eccentric pin 34Y-c and the rear boss 8k are engaged with each other. Each eccentric pin or boss fits in a corresponding long hole so that it can slide in the longitudinal direction but cannot move in the width direction.
[0067]
Finally, the support plate fixing screws 66 are screwed into the front and rear screw screw holes 36d and 37d, and the second group lens frame support plates 36 and 37 are fastened together. The support plate fixing screw 66 is first screwed into the front screw screw hole 36d, and then screwed into the rear screw screw hole 37d through the screw insertion hole 8h. When the support plate fixing screw 66 is tightened in a state of being screwed into both the screw screw holes 36d and 37d, the second group lens frame support plate 36 is pressed against the front support plate mounting surface 8c. 37 is pressed against the rear support plate mounting surface 8e, and the second group lens frame support plate 36 and the second group lens frame support plate 37 are separated by an interval in the optical axis direction between the front support plate mounting surface 8c and the rear support plate mounting surface 8e. In this state, the second group lens moving frame 8 is fixed. As a result, the first eccentric shaft member 34X and the second eccentric shaft member 34Y are prevented from coming off in the optical axis direction by the second group lens frame support plate 36 and the second group lens frame support plate 37. The second group rotating shaft 33 is regulated to move rearward by bringing the flange 33a into contact with the second group lens frame support plate 37, and the swinging central cylinder 6b is moved forward via an axial pressing spring 38 in a compressed state. In order to press, the front end portion of the swing center tube 6 b is pressed against the second group lens frame support plate 36. Thereby, the position in the optical axis direction of the second group lens frame 6 with respect to the second group lens moving frame 8 is kept constant. When the second group lens frame support plate 37 is fixed to the second group lens moving frame 8, the guide key entry groove 37g and the key groove 8p communicate with each other in the optical axis direction (see FIG. 30).
[0068]
When the second group lens frame support plate 36 is fixed, the front spring end 39a of the second group lens frame return spring 39 is engaged with the spring hook 36g. The rear spring end 39b is already engaged with the swing arm 6c, and by engaging the front spring end 39a and the spring hook 36g, the second group lens frame return spring 39 is bent, and the second group lens frame 6 is engaged. On the other hand, when viewed from the front in the optical axis direction (FIG. 32), a counterclockwise rotation urging force acts on the second group rotation shaft 33.
[0069]
Separately from the attachment of the second group lens frame 6, the rotation restriction pin 35 is inserted into the rotation restriction pin insertion hole 8 m of the second group lens moving frame 8. The rotation restricting pin insertion hole 8m has an inner shape that restricts further insertion when the rotation restricting pin 35 is inserted to the position shown in FIGS. 26 and 27. As shown in FIG. 27, the eccentric pin 35b protrudes rearward from the rotation restricting pin insertion hole 8m.
[0070]
In the state where the second group lens frame 6 is attached to the second group lens moving frame 8 as described above, the second group lens frame 6 can rotate (swing) about the second group rotation shaft 33. The swing center tube housing hole 8g of the second group lens moving frame 8 is formed sufficiently wide so as not to interfere with the swing center tube 6b and the swing arm 6c even if the second group lens frame 6 swings. . Since the second group rotation shaft 33 is an axis parallel to the optical axis, the second lens group LG2 maintains its optical axis parallel to the photographing optical axis Z1 as the second group lens frame 6 rotates. However, it is moved in parallel. The second group lens frame 6 has one rotation end (oscillation end) determined by the tip of the stopper arm 6e coming into contact with the eccentric pin 35b. The second group lens frame return spring 39 biases the second group lens frame 6 in a direction in which the stopper arm 6e is brought into contact with the eccentric pin 35b.
[0071]
A shutter unit 76 is further attached to the second group lens moving frame 8. Sub-asserted to the state shown in FIGS. As can be seen from FIGS. 26 and 28, the shutter unit 76 is fixed to the front side of the intermediate flange portion 8s. The front support plate mounting surface 8c is positioned in front of the shutter S and the diaphragm A in the shutter unit 76 in the fixed state in the optical axis direction. The lens barrel 6a of the second group lens frame 6 has a partial region on the front end side located in the second group lens moving opening 8t, and immediately after the shutter unit 76 regardless of the angular position of the second group lens frame 6. It is supposed to be located in.
[0072]
The second group lens moving frame 8 has three rectilinear guide grooves 8a formed at different positions in the circumferential direction. One of the rectilinear guide grooves 8a-W is more than the remaining two rectilinear guide grooves 8a. It is wide and the bottom portion penetrates in the radial direction, and the exposure control FPC board 77 extending from the shutter unit 76 can be guided to the outside of the second group lens moving frame 8 through the straight guide groove 8a-W. It has become. Correspondingly, one of the three rectilinear guide keys 10c provided in the second group rectilinear guide ring 10 is a wide rectilinear guide key 10c-W corresponding to the width of the rectilinear guide groove 8a-W. The straight guide key 10c-W is formed with an FPC through hole 10d (FIG. 15) penetrating in the radial direction by partially notching the vicinity of the connection portion with the ring portion 10b.
[0073]
In a state in which the second group lens moving frame 8 and the second group linear guide ring 10 are combined, the exposure control FPC board 77 is arranged as shown in FIG. First, the first linear portion 77a extends from the shutter unit 76 toward the rear in the optical axis direction, and then a U-shaped portion (loop-shaped portion) 77b is formed near the rear end portion of the second group lens moving frame 8. The second linear portion 77c is moved forward along the inner peripheral surface of the rectilinear guide key 10c-W and folded outward at the tip of the rectilinear guide key 10c-W. The third linear portion 77d extends rearward again along the outer peripheral surface of -W. The tip of the third linear portion 77d is connected to the control circuit 140 after extending to the rear of the second group lens moving frame 8 through the FPC through hole 10d. In the exposure control FPC board 77, a part of the third linear portion 77d is fixed to the outer peripheral surface of the rectilinear guide key 10c-W using a double-sided tape or the like, and the second group lens moving frame 8 and the second group rectilinear guide ring. The size of the U-shaped portion 77c can be changed in accordance with the 10 relative movements.
[0074]
The second group lens moving frame 8 sub-assembled as described above is moved in the optical axis direction via the cam ring 11, and behind the second group lens moving frame 8 is the movement of the cam ring 11. An AF lens frame 51 is supported so as to be able to advance and retract independently in the optical axis direction, and a CCD holder 21 is fixed behind the AF lens frame 51.
[0075]
  The AF lens frame 51 is made of a light-shielding material, and is not shown in FIGS. 38 to 41 and FIG.FigureAs shown in 47, it has a pair of arm parts 51d and 51e which have the guide holes 51a and 51b, and the front protrusion cylindrical part 51c which protrudes ahead rather than these arm parts 51d and 51e. The front protruding cylindrical portion 51c includes a front end surface (bottom surface) 51c1 that is perpendicular to the imaging optical axis Z1 and forms a substantially square shape, and four side surfaces 51c3 that extend from each side of the front end surface 51c1 to the CCD 60 side in parallel to the imaging optical axis Z1. It has a box shape (square tube shape) having 51c4, 51c5 and 51c6, and the rear end portion on the opposite side to the front end surface 51c1 is open toward the low-pass filter LG4 and the CCD 60 side. A circular opening 51c2 whose center coincides with the photographing optical axis Z1 is provided on the front end surface 51c1 of the forward projecting cylindrical part 51c, and the third lens group LG3 is supported inside the opening 51c2. The arm portions 51d and 51e have a photographing optical axis from the upper left portion and the lower right portion when viewed from the front, that is, the vicinity of the intersection line of the side surfaces 51c3 and 51c6 and the vicinity of the intersection line of the side surfaces 51c4 and 51c5. It extends toward the radial direction (radial direction) centered on Z1 (see FIG. 47). As can be seen from FIGS. 45 and 46, the arm portions 51d and 51e are provided on the side surfaces 51c3 and 51c6 and the rearmost portions of the side surfaces 51c4 and 51c5 in the optical axis direction.
[0076]
As shown in FIG. 6, the arm portions 51 d and 51 e of the AF lens frame 51 have respective tip portions protruding outside the annular portion 22 f of the fixed ring 22, and guides parallel to the optical axis are formed on the protruding tip portions. Holes 51a and 51b are formed. Correspondingly, an AF guide shaft 52 that engages with the guide hole 51a and performs main guidance of the AF lens frame 51, and an AF guide shaft 53 that engages with the guide hole 51b and performs auxiliary guidance of the AF lens frame 51; Are located outside the annular portion 22 f of the stationary ring 22. In the annular portion 22f, in order to avoid interference with the arm portions 51d and 51e when the AF lens frame 51 moves in the optical axis direction, notches 22g and 22h in the optical axis direction along the AF guide shafts 52 and 53 ( FIG. 8) is formed. Further, as shown in FIGS. 39 and 47, the guide hole 51a and the guide hole 51b are formed at positions facing each other with respect to the photographing optical axis Z1, and the AF guide shafts 52 and 53 also correspond to the photographing optical axis. They are provided in a positional relationship facing each other with respect to Z1.
[0077]
The AF lens frame 51 can move rearward in the optical axis direction until the arm portions 51d and 51e come into contact with the movement restricting surface 21b (FIG. 6) of the CCD holder 21, and when the AF lens frame 51 moves to the rearward movement end. The leading end of the cam projection 21a that protrudes forward from the CCD holder 21 in the optical axis direction protrudes forward from the AF lens frame 51 (see FIGS. 38, 40, and 41). On the extension of the cam protrusion 21a in the optical axis direction, a cam protrusion insertion / removal opening 37c of the second group lens frame support plate 37 and a cam protrusion insertion / removal opening 36c of the second group lens frame support plate 36 are located.
[0078]
As shown in FIG. 21 and FIG. 22, a retracting cam surface 21c that is inclined with respect to the optical axis is formed at the tip of the cam projection 21a, and an optical axis and a side surface that is continuous with the retracting cam surface 21c are formed. A parallel retracted position holding surface 21d is formed. As can be seen from FIGS. 35 to 37 as viewed from the front, the cam protrusion 21a is formed to be wide in the radial direction about the photographing optical axis Z1, and the retracting cam surface 21c is the width of the cam protrusion 21a. Formed as an inclined surface that gradually increases the amount of projection forward in the optical axis direction as the direction advances from the inner diameter side of the lens barrel (side closer to the imaging optical axis Z1) to the outer diameter side of the lens barrel (side far from the imaging optical axis Z1). Has been. In FIG. 35 to FIG. 37, hatching is added to make it easy to distinguish the retreat cam surface 21c. The cam projection 21a has a slightly curved cross-sectional shape so that the lower surface side is convex and the upper surface side is concave so as to avoid interference with the swinging central cylinder 6b of the second group lens frame 6. On the side, a guide key 21e parallel to the optical axis is projected. The guide key 21e is formed only within a certain range from the base of the cam protrusion 21a, and is not formed near the tip of the cam protrusion 21a. The guide key 21e has a cross-sectional shape that can be engaged with the guide key entry groove 37g.
[0079]
The second lens group LG2 and the third lens group LG3 supported by the above structure operate in the following manner. As described above, the position of the second group lens moving frame 8 with respect to the CCD holder 21 in the optical axis direction is front and rear according to the locus of the second group guide cam groove 11a (the front cam groove 11a-1 and the rear cam groove 11a-2) of the cam ring 11. It is determined by combining the movement and the back-and-forth movement of the cam ring 11 itself. In short, the second group lens moving frame 8 is farthest from the CCD holder 21 in the vicinity of the wide end shown in the upper half of FIG. By utilizing the retreating operation of the second group lens moving frame 8 from the wide end to the storage position, the second group lens frame 6 is retracted in the outer diameter direction within the second group lens moving frame 8.
[0080]
In the zoom range from the wide end to the tele end, the position of the second group lens frame 6 is kept constant by bringing the stopper arm 6e into contact with the rotation restricting pin 35 by the urging force of the second group lens frame return spring 39. At this time, the optical axis of the second lens group LG2 coincides with the photographing optical axis Z1 as shown in FIG. As shown in FIG. 29, at the photographing position of the second group lens frame 6, a part of the retracting arm 6j and the movable spring end 40b of the rotation transmitting spring 40 face the cam protrusion insertion / removal opening 37c.
[0081]
When the main switch of the camera is turned off from the photographing state, the control circuit 140 drives the AF motor 160, the AF lens frame 51 is retracted and approaches the CCD holder 21, and the rearward moving end shown in FIGS. It is stored in. The forward protruding cylindrical portion 51c of the AF lens frame 51 supports the third lens group LG3 on the front end surface 51c1 side, and the rear of the third lens group LG3 is an open space surrounded by the side surfaces 51c3, 51c4, 51c5 and 51c6. Therefore, when the AF lens frame 51 moves to the rearward movement end in FIG. 7, the low-pass filter LG4 and the CCD 60 that are supported by projecting from the front surface of the CCD holder 21 enter the front projecting cylindrical portion 51c. The interval with the third lens group LG3 is narrowed. Further, when the AF lens frame 51 reaches the rearward movement end, the tip end portion of the cam projection 21 a is projected forward from the AF lens frame 51.
[0082]
Subsequently, the control circuit 140 drives the zoom motor 150 in the storage direction, and the lens barrel storage operation described above is performed. When the zoom motor 150 is driven in the storing direction beyond the wide end, the cam ring 11 moves rearward in the optical axis direction while rotating due to the relationship between the roller guide through groove 14e and the cam ring roller 32. As can be seen from the relationship between the second group guide cam groove 11a and the second group cam follower 8b shown in FIG. 14, the second group lens moving frame 8 is more retracted relative to the cam ring 11 in the optical axis direction than in the wide end. However, the amount of backward movement of the cam ring 11 with respect to the fixed ring 22 is larger than the amount of forward movement of the second group lens moving frame 8 in the cam ring 11, so that the second group lens moves during the storage operation. The frame 8 approaches the CCD holder 21 as a whole.
[0083]
When the second group lens moving frame 8 continues to move backward together with the second group lens frame 6, the tip of the cam protrusion 21a eventually enters the cam protrusion insertion / removal opening 37c (FIG. 23). As described above, a part of the retracting arm 6j and the movable spring end 40b of the rotation transmission spring 40 face the cam projection insertion / removal opening 37c in the photographing state. At this time, the retracting arm 6j and the movable spring end The positional relationship seen from the front of the part 40b and the cam protrusion 21a is as shown in FIG. In the radial direction centered on the photographing optical axis Z1, the movable spring end 40b protrudes toward the cam protrusion 21a from the retracting arm 6j (excluding the protrusion for forming the spring hooking hole 6k). On the other hand, the retracting cam surface 21c is a slope that increases the forward projection amount as the distance from the photographing optical axis Z1 increases. In other words, the retracting cam surface 21c is an inclined surface that increases the amount of protrusion toward the front side of the paper as it goes to the right in FIG. 35, and the region of the retracting cam surface 21c that protrudes forward is the end of the movable spring. It is located behind 40b. Therefore, when the second group lens frame 6 moves backward to the CCD holder 21 side together with the second group lens moving frame 8 while maintaining the positional relationship of FIG. 35, the retracting cam surface 21c contacts the movable spring end 40b instead of the retracting action arm 6j. Touch. FIG. 40 shows the position of the second group lens frame 6 immediately before the movable spring end 40b comes into contact with the retraction cam surface 21c.
[0084]
When the second group lens frame 6 moves backward in a state where the movable spring end 40b and the retracting cam surface 21c are in contact with each other, a component force is generated that presses the movable spring end 40b in the clockwise direction in FIG. 35 according to the shape of the retracting cam surface 21c. The clockwise rotational force is transmitted to the second group lens frame 6 through the fixed spring end 40a on the other end side of the rotation transmitting spring 40. The spring force (hardness) of the rotation transmitting spring 40 is not deflected more than the state shown in FIG. 35 depending on the rotational resistance acting on the second group lens frame 6 itself in a normal barrel housing operation. 6 is set so as to transmit the rotational force to 6. That is, the elastic restoring force of the rotation transmitting spring 40 is set to be stronger than the urging force that the second group lens frame return spring 39 holds the second group lens frame 6 in the photographing position.
[0085]
The second group lens frame 6 that has received the rotational pressing force by the retreat cam surface 21c is moved from the photographing position shown in FIG. 29 toward the retreat position shown in FIG. It rotates about the second group rotation shaft 33 against the urging force of the lens frame return spring 39. Accordingly, the movable spring end 40b moves on the retracting cam surface 21c from the position of FIG. 35 toward the position of FIG. When the second group lens frame 6 is rotated to the retracted position in FIG. 30, the movable spring end 40b gets over the retracted cam surface 21c and engages with the retracted position holding surface 21d as shown in FIG. Even if the frame 8 performs the backward movement, the turning power in the retracting direction is not applied to the second group lens frame 6. In the second group lens frame 6 held at the retracted position, the outer edge of the lens tube 6a enters the lens tube entry recess 8q, and the outer edge of the stopper arm 6e enters the stopper arm entry recess 8r.
[0086]
Even after the second group lens frame 6 reaches the retracted position, the second group lens moving frame 8 continues to retract until it reaches the storage position shown in FIG. The second group lens frame 6 moves back to the position shown in FIG. 41 together with the second group lens moving frame 8 while being held at the retracted position with the movable spring end 40b engaged with the retracted position holding surface 21d. At this time, the tip end portion of the cam projection 21a penetrates through the swinging center tube storage hole 8g and projects forward from the cam projection insertion / removal opening 36c.
[0087]
As shown in FIGS. 7 and 41, in the retracted state, the lens cylinder 6a is moved to a space outside (upper) the front protruding cylindrical part 51c of the AF lens frame 51, and the front protruding cylindrical part 51c is When shooting, the second lens group LG2 enters the space in the second group lens moving frame 8 where the second lens group LG2 was located, and the third lens group LG3 is positioned immediately after the shutter unit 76. Further, as can be seen from the comparison between FIG. 6 and FIG. 7, when the AF lens frame 51 is moved to the rearward movement end, the low-pass filter LG4 and the CCD 60 are accommodated (entered) into the forward projecting cylindrical portion 51c and third. The relative distance in the optical axis direction with respect to the lens group LG3 is smaller than in the shooting state. That is, the second lens group LG2 is in a state in which the position in the optical axis direction overlaps (aligns in the radial direction) with respect to the third lens group LG3, the low-pass filter LG4, and the CCD 60. With conventional lens barrels that move optical elements such as lens groups that make up the photographic optical system only in the direction of the optical axis, the barrel storage length must be shortened beyond the total thickness of multiple optical elements. However, according to the structure of the present embodiment, the storage space for the second lens group LG2 in the optical axis direction can be substantially omitted, and the lens barrel storage length can be shortened. Yes.
[0088]
In the present embodiment, the shape of the AF lens frame 51 and the support structure thereof are particularly devised in order to obtain the storage state with excellent space efficiency as described above. That is, in order to retract the second lens group LG2 to the position of FIG. 7, the AF guide shafts 52 and 53, which are guide mechanisms of the AF lens frame 51, are arranged outside the annular portion 22f of the fixed ring 22, and the AF The arm portions 51d and 51e of the AF lens frame 51 that receives the guidance of the guide shafts 52 and 53 are extended from the rear end portion in the optical axis direction of the front protruding cylindrical portion 51c. First, by arranging the AF guide shafts 52 and 53 outside the annular portion 22f of the fixed ring 22, the second group lens frame 6 and the second group lens moving frame 8, without fear of interfering with the AF guide shafts 52 and 53, Furthermore, the moving space of the cam ring 11 and the helicoid ring 18 which are rotating rings for moving them in the optical axis direction can be obtained inside the fixed ring 22. In other words, since the AF guide shafts 52 and 53 can be arranged without being restricted by a moving member such as the second group lens frame 6 positioned inside the fixed ring 22, the AF guide shafts 52 and 53 with respect to the AF guide frame 51 are arranged. It has become possible to obtain a high guide accuracy by taking a sufficiently long guide length. Further, the arm portions 51d and 51e are provided not at the front end portion or the middle portion of the front protruding cylindrical portion 51c but at the rear end portion, so that they are formed by the outside of the front protruding cylindrical portion 51c and the front of the arm portions 51d and 51e. The space to be played is widened. Thereby, the second group lens frame 6 is retracted (collapsed) to a deep position where the substantially entire lens tube 6a and the position of the front projecting cylindrical portion 51c overlap with each other without being limited to the arm portions 51d and 51e. It became possible to do.
[0089]
Further, in the AF lens frame 51, the third lens group LG3 is supported at the front end portion of the front protruding cylindrical portion 51c, and in the housed state, the low-pass filter LG4 and the CCD 60 are housed behind the third lens group LG3. Therefore, it is possible to obtain a storage state that is more space efficient.
[0090]
In addition to the above, in the storing operation from the wide end, not only the second group lens moving frame 8 but also the first outer cylinder 12 supporting the first lens group LG1 is retracted together with the cam ring 11, and the storing shown in FIG. In the state, the relative distance in the optical axis direction between the first lens group LG1 and the third lens group LG3 is also small with the shutter unit 76 interposed therebetween. That is, in the zoom lens barrel 71 of the present embodiment, the length in the optical axis direction when the first optical lens group LG1 at the forefront of the photographing optical system is retracted to the rearmost CCD 60 is the same as that of the conventional lens barrel. It is extremely shortened. The first lens group frame 1 is provided with a contact portion 1b (FIGS. 6 and 7) that protrudes rearward from the rearmost portion of the first lens group LG1 and can contact the shutter unit 76. The group LG1 is prevented from coming into direct contact with the shutter unit 76.
[0091]
When the main switch of the camera is turned on in the retracted state, the zoom motor 150 is driven in the extending direction by the control circuit 140, and the above-described elements operate in the reverse manner. That is, the cam ring 11 is extended forward while rotating with respect to the linear guide ring 14, and the second group lens moving frame 8 and the first outer cylinder 12 move forward together with the cam ring 11. In the initial stage of advancement of the second group lens moving frame 8, the movable spring end 40b of the rotation transmitting spring 40 is engaged with the retracted position holding surface 21d, so that the second group lens frame 6 is maintained at the retracted position. When the second group lens moving frame 8 moves forward to some extent, the movable spring end 40b reaches the tip of the cam projection 21a, and is separated from the retracted position holding surface 21d and engages with the retracted cam surface 21c (FIG. 37). At this stage, the lens barrel 6a of the second group lens frame 6 has already moved forward from the forward projecting cylindrical portion 51c of the AF lens frame 51, and even if the second group lens frame 6 starts to rotate in the photographing position direction. It does not interfere with the AF lens frame 51. As the second group lens moving frame 8 further moves forward, the movable spring end 40b moves on the retreat cam surface 21c, and the second group lens frame 6 is retracted by the urging force of the second group lens frame return spring 39. Rotation starts from the position toward the shooting position.
[0092]
When the second group lens frame 6 rotates to the position shown in FIG. 35 while sliding the movable spring end 40b on the retraction cam surface 21c, and the second group lens moving frame 8 moves forward, the movable spring end 40b moves to the retraction cam. It leaves | separates from the surface 21c. As a result, the restriction by the cam protrusion 21 a is completely released, and the second group lens frame 6 is engaged with the eccentric pin 35 b of the rotation restriction pin 35 by the biasing force of the second group lens frame return spring 39. It is held at the shooting position. That is, the optical axis of the second lens group LG2 coincides with the photographing optical axis Z1 as in the other lens groups. The rotation of the second group lens frame 6 to the photographing position is completed before reaching the wide end.
[0093]
Note that when the storage state is changed to the photographing state, the AF lens frame 51 is moved forward from the above-described rearward movement end. However, as shown in FIG. The portion 51c covers the front of the low-pass filter LG4 and the CCD 60, and the tip surface 51c1 and the side surfaces 51c3 to 53c6 of the front-projecting cylindrical portion 51c are connected to the low-pass filters LG4 and CCD60 from portions other than the third lens group LG3. Excessive incident light can be reduced. That is, the forward protruding cylindrical portion 51c of the AF lens frame 51 not only supports the third lens group LG3, but also functions as a storage portion that stores the low-pass filter LG4 and the CCD 60 in the storage state, and the low-pass filter LG4 in the shooting state. Also, it functions as a light shielding portion that prevents the extra light from entering the CCD 60.
[0094]
With respect to the movable lens group, a high accuracy is required for its support structure so as not to impair the photographing performance. In particular, as in the case of the present lens barrel, the movable lens group is not only moved in the optical axis direction but also retracted. When swinging for the second lens group LG2, the accuracy required for the second group lens frame 6 and the second group rotation shaft 33 related to the retraction operation of the second lens group LG2 is higher than that of a normal movable member. A few steps higher. For example, in a conventional lens barrel, when a rotation center shaft such as the second group rotation shaft 33 is disposed in an annular body having an exposure control member such as a shutter S or an aperture A, the rotation center shaft is exposed. It could only be provided in either the front or rear space of the member, and the axial length was limited or a cantilevered support structure was achieved. However, since a minimum clearance for allowing relative rotation is required between the rotation center shaft such as the second group rotation shaft 33 and the shaft hole portion such as the swing shaft hole 6d, the rotation center is required. When the shaft length is short or the support structure is cantilevered, there is a possibility that a fall occurs between the two due to this clearance. It is necessary to eliminate the tilt that does not cause a problem in the conventional lens support structure with the optical accuracy required by the present embodiment.
[0095]
In this lens group retracting structure, as can be seen from FIG. 31, the front support plate mounting surface 8 c and the rear support plate mounting surface 8 e that are spaced apart from each other with the shutter unit 76 interposed therebetween are divided into the second group lens frame support plates 36 and 2. Since it is sandwiched between the group lens frame support plates 37 and the second group rotation shaft 33 is spanned between the second group lens frame support plate 36 and the second group lens frame support plate 37, The support structure is a double-sided structure that does not easily collapse. In addition, since the second group lens frame support plates 36 and 37 related to the support of the second group rotation shaft 33 and the swinging center tube storage hole 8g are formed at positions that do not overlap the shutter unit 76, the second group rotation. The shaft length of the shaft 33 can be increased regardless of the shutter unit 76 (without causing interference). Actually, the axial length of the second group rotating shaft 33 of the present embodiment is long enough to be comparable to the length of the second group lens moving frame 8 in the optical axis direction. Correspondingly, the axial length of the swinging central cylinder 6b sandwiched between the second group lens frame support plate 36 and the second group lens frame support plate 37 is also increased. That is, a sufficiently long engagement length is secured between the swing shaft hole 6 d and the second group rotation shaft 33. From the above structure, there is little possibility that the second group lens frame 6 is tilted with respect to the second group rotation shaft 33, and the second group lens frame 6 can be driven with high accuracy.
[0096]
The second group lens frame support plate 36 and the second group lens frame support plate 37 are respectively positioned by a front boss 8j and a rear boss 8k protruding from the front support plate mounting surface 8c and the rear support plate mounting surface 8e. The front support plate mounting surface 8c and the rear support plate mounting surface 8e are pressure-bonded by a common support plate fixing screw 66. Therefore, the positional accuracy of the second group lens frame support plate 36 and the second group lens frame support plate 37 with respect to the second group lens moving frame 8, that is, the positional accuracy of the second group rotating shaft 33 with respect to the second group lens moving frame 8 may be increased. it can.
[0097]
In the present embodiment, the rear support plate mounting surface 8e is flush with the rear end surface of the second group lens moving frame 8, whereas the front support plate mounting surface 8c is in front of the second group lens moving frame 8. Further, a partial cylindrical portion 8d protrudes further forward, and the front support plate mounting surface 8c is not a front end surface of the second group lens moving frame 8 in a strict sense. However, in the case where the second group lens moving frame 8 is a simple end face-shaped annular body that does not have a protruding portion such as the partial cylindrical portion 8d, the front and rear end faces are directly sandwiched between a pair of shaft support plates. It is good also as such a structure.
[0098]
Further, in the above lens group retracting structure, if the second group lens frame 6 is gradually retracted and rotated using the entire range of the storage movement distance of the second group lens moving frame 8 from the wide end to the storage position, it is in the middle. Since the second group lens frame 6 interferes with the forward protruding cylindrical portion 51c of the AF lens frame 51, the revolving rotation of the second group lens frame 6 is completed within a short distance of the storage movement distance, and then the lens. It is necessary to leave a moving distance for translating the cylinder 6a rearward in the optical axis direction and retracting it to the space above the front protruding cylindrical portion 51c. In order to secure a sufficient retraction rotation angle with a short movement distance, a retraction cam surface 21c is provided with a so-called lead having a large crossing angle with respect to the advancing / retreating direction of the second group lens moving frame 8 (ie, the direction parallel to the optical axis) It must be a tilted inclined surface. When pressing the movable spring end 40b with such a retracting cam surface 21c, compared to when pressing with a cam surface having a small crossing angle with respect to the advancing / retreating direction of the second group lens moving frame 8 (the lead is neglected), A large reaction force acts on the cam projection 21a and the second group lens moving frame 8.
[0099]
The cam protrusion 21 a is a fixing member similar to the fixing ring 22. On the other hand, the second group lens moving frame 8 is guided straight, but as shown in FIG. 19, it does not receive the straight guide directly from the fixed ring 22, but the straight guide ring 14 and the second group straight guide ring 10. Such a straight guide through the intermediate member, and each of the straight guide mechanisms has a fitting clearance. Therefore, when a large reaction force acts on the cam projection 21a or the second group lens moving frame 8, the positional relationship between the second group lens moving frame 8 and the CCD holder 21 is incorrect due to this fitting clearance. The possibility of affecting the evacuation operation must be considered. For example, when the second group lens frame 6 is rotated to the retracted position, if it proceeds further in the retracted direction than the designed position (FIG. 30), it will interfere with the inner wall surface of the second group lens moving frame 8. On the other hand, if it stops before the designed retracted position, there is a risk of interference with the AF lens frame 51 and the like.
[0100]
In this lens group retracting structure, when the second group lens frame 6 is rotated to the retracted position, a guide key 21e provided on the cam protrusion 21a is engaged with the key groove 8p, whereby the cam protrusion 21a and the second group lens are engaged. It is possible to prevent the displacement of the moving frame 8 and hold the second group lens frame 6 at an accurate retracted position (see FIG. 24). More specifically, the movable spring end 40b is engaged with the retracted position holding surface 21d so that the retracted state of the second group lens frame 6 is maintained, and the second group lens moving frame 8 has a room for retreat. In the middle of the operation, the guide key 21e enters the swinging center tube storage hole 8g through the guide key entry groove 37g formed in the second group lens frame support plate 37, and engages with the key groove 8p. Since the guide key 21e and the key groove 8p are a groove and a projection parallel to the optical axis, respectively, when the guide key 21e and the key groove 8p are engaged, the second group lens moving frame 8 and the cam protrusion 21a are in the optical axis direction. Is relatively movable, and the relative movement of the key groove 8p in the groove width direction is restricted. The groove width direction of the key groove 8p substantially coincides with the rotation direction of the second group lens frame 6. Therefore, even if a reaction acts on the second group lens moving frame 8 when the second group lens frame 6 is pressed by the retracting cam surface 21c, the second group lens moving frame 8 and the cam projection are engaged by the engagement of the guide key 21e and the key groove 8p. Since 21a is kept in an appropriate positional relationship, there is no possibility that the retracted position of the second group lens frame 6 is shifted.
[0101]
In this embodiment, the timing for engaging the guide key 21e and the key groove 8p is after completion of the retracting operation of the second group lens frame 6 by the retracting cam surface 21c, but the timing of starting the engagement is retracted. It may be set during the operation or before the evacuation operation. In short, when the second group lens frame 6 is finally held at the retracted position, the positional relationship between the second group lens moving frame 8 and the cam projection 21a should be accurate. The timing for engaging the guide key 21e and the key groove 8p can be arbitrarily set by changing the formation region of the guide key 21e in the optical axis direction, for example.
[0102]
Further, in this embodiment, the guide key 21e on the cam projection 21a side is a convex part and the key groove 8p on the second group lens moving frame 8 side is a concave part, but the relationship between the concaves and convexes may be reversed.
[0103]
Furthermore, in this embodiment, the guide key 21e is formed on the cam projection 21a having the retreat cam surface 21c. However, a portion corresponding to the guide key 21e may be formed on the CCD holder 21 at a place other than the cam projection 21a. Is possible. However, from the viewpoint of simplifying the structure, the guide key 21e is preferably formed on the cam protrusion 21a together with the retracting cam surface 21c. In addition, it is more accurate to form the guide key 21e on the cam projection 21a itself, which is an engagement portion with the second group lens moving frame 8 (strictly, the second group lens frame 6) side with respect to the second group lens moving frame 8. It is also effective from the viewpoint of taking out.
[0104]
Further, in addition to the reaction force acting on the second group lens moving frame 8 and the cam projection 21a when the second group lens frame 6 is retracted and rotated, the positional accuracy of the parts constituting the lens group retracting mechanism is also the same as that of the second group lens frame 6. Affects operation accuracy. As described above, the amount of retraction rotation given to the second group lens frame 6 is not preferable even if it is excessive or insufficient, but in this embodiment, the second group lens is particularly in a state where the lens barrel 6a and the stopper arm 6e are retracted. Because of space saving by making it very close to the inner wall surface of the moving frame 8 (see FIG. 30), a force that causes the second group lens frame 6 to exceed the proper retraction position shown in FIG. If this is applied, stress will be applied to the retracting mechanism, and it is required to avoid this.
[0105]
In order to solve this problem, in the present lens group retracting structure, the position where the retracting cam surface 21c of the cam projection 21a and the retracting position retaining surface 21d abut when the retracting rotation of the second group lens frame 6 is rotated is transmitted instead of the retracting arm 6j. The movable spring end 40b of the spring 40 is used, and the movement of the second group lens frame 6 can be absorbed by bending the rotation transmitting spring 40. As described above, the rotation transmission spring 40 transmits the rotational force to the second lens group frame 6 without being bent more than the shape shown in FIGS. 35 and 37 in the normal retraction operation. Since there is still room to bend the portion 40b by θ1 at the maximum, even if there is a positional error that the cam projection 21a is slightly shifted to the left of the position of FIG. 37, the movable spring end 40b is fixed to the fixed spring end. This positional error can be absorbed by bending in the direction approaching 40a. That is, the cam projection 21a is further in a state where the second group lens frame 6 (lens cylinder 6a and stopper arm 6e) is in contact with the inner peripheral surface of the second group lens moving frame 8 (lens cylinder entry recess 8q and stopper arm entry recess 8r). Even if the pressing force is applied, it is possible to prevent an excessive stress from being applied to the retracting mechanism of the second group lens frame 6 due to the rotation transmitting spring 40 being bent.
[0106]
In the present lens group retracting structure, as shown in FIG. 30, the swing arm 6c of the second group lens frame 6 held at the retracted position is formed in the rectilinear guide groove 8a-W through which the exposure control FPC board 77 is inserted. Adjacent to the inside, the surface on the outer diameter side of the swing arm 6c blocks a part of the bottom of the straight guide groove 8a-W. Conversely, a rectilinear guide groove 8a-W is formed on the outer diameter side of the intermediate position of the line segment connecting the second group rotation shaft 33 and the retracting optical axis Z2, and the exposure control FPC board 77 is passed through. As a result, the swing arm 6c can support the exposure control FPC board 77 from the inner diameter side of the lens barrel when the second group lens frame 6 is at the retracted position, and the exposure control FPC board in the support state. The relationship between 77 and the second group lens frame 6 is shown by a solid line in FIG. In the figure, a two-dot chain line indicates the second group lens frame 6 at the photographing position. As can be seen from FIG. 43, the swing arm 6c supports the U-shaped portion 77b and the first linear portion 77a of the exposure control FPC board 77 from the inside, and the exposure control FPC board 77 is slackened in the inner diameter direction of the lens barrel. Is preventing.
[0107]
Specifically, the swing arm 6c has a linear support surface 6q that is parallel to the first linear portion 77a during retraction, and a shape adjacent to the rear of the linear support surface 6q that matches the shape of the U-shaped portion 77b. An inclined support surface 6r that is inclined and an FPC support protrusion 6s that protrudes rearward from the inclined support surface 6r are provided. In the retracted position of the second group lens frame 6, the linear support surface 6q is positioned to support the first linear portion 77a, and the inclined support surface 6r and the FPC support protrusion 6s are positioned to support the U-shaped portion 77b. .
[0108]
A flexible printed circuit board (flexible printed circuit board, hereinafter referred to as FPC) that connects the advance / retreat member in the optical axis direction and the fixed member in the lens barrel needs to have a length corresponding to the maximum extended state of the advance / retreat member. When the amount of advancement and retraction of the advancement / retraction member is minimum, that is, in the lens barrel storage state, the length of the FPC is excessive, and slack is easily generated. In particular, in the present embodiment, the second lens group LG2 is retracted on the retracting optical axis Z2, and the length in the optical axis direction when the zoom lens barrel 71 is stored is greatly shortened, and this tendency is strong. If the slack portion of the FPC interferes with or is pinched by other lens barrel components, it may cause a failure or breakage. Therefore, a structure that prevents the slack is necessary, but the structure for preventing the slack of the FPC in the conventional lens barrel is complicated. There were many things. On the other hand, in 71 of the present embodiment, focusing on the fact that the lens barrel storage state in which the exposure control FPC board 77 is likely to be slack is the retracted state of the second group lens frame 6, the second lens group in the retracted position. Since the frame 6 is used to support the exposure control FPC board 77, it is possible to reliably prevent the exposure control FPC board 77 from slacking with a simple structure.
[0109]
In the retracting structure of the second group lens frame 6 of the present embodiment, the second group lens frame 6 moves backward while rotating when the second group lens frame 6 moves to the retracted position, so that the movement locus advances obliquely rearward from the photographing optical axis Z1. It becomes. On the other hand, the AF lens frame 51 is positioned behind the second group lens frame 6 in the photographing state. As shown in FIGS. 39 to 41, a retraction direction inclined surface 51h is formed on the front protruding cylindrical portion 51c of the AF lens frame 51 from the front end surface 51c1 to the upper side surface 51c5. The retraction direction inclined surface 51h is inclined so as to gradually move backward in the optical axis direction as it proceeds in the radial direction (outer diameter direction) centering on the photographing optical axis Z1, and in short, the second group lens frame 6 The surface is cut out along the movement locus of the lens barrel 6a. The retraction direction slope 51h is a curved concave surface corresponding to the outer shape of the lens tube 6a.
[0110]
As described above, during the lens barrel storage operation, the AF lens frame 51 moves to the rearward movement end (storage position) where the AF lens frame 51 contacts the movement restriction surface 21b of the CCD holder 21 before the retracting operation of the second group lens frame 6 occurs. (FIGS. 40 and 41). When the retracting operation of the second group lens frame 6 is performed in this state, the rear end portion of the lens barrel 6a moves obliquely rearward and approaches the retracting direction inclined surface 51h, so that the retracting direction inclined surface 51h is grazed as shown in FIG. Moved to position. That is, the retracting operation of the second group lens frame 6 can be performed at a position close to the AF lens frame 51 by an amount corresponding to the cutout of the retracting direction slope 51h.
[0111]
Here, assuming that there is no inclined surface such as the retracting direction inclined surface 51h, in order to avoid interference with the AF lens frame 51, the rotation of the second group lens frame 6 to the retracted position is earlier than in this embodiment. Must complete. For this purpose, it is necessary to make the backward movement amount of the second group lens moving frame 8 longer or to increase the protrusion amount of the cam projection 21a, which is contrary to the downsizing of the lens barrel. Further, if the amount of backward movement of the second group lens moving frame 8 is constant, the inclination angle of the retracting cam surface 21c with respect to the optical axis must be increased. However, if the inclination of the cam surface is too large, the reaction force at the time of pressing is large. (Resistance) increases, which is not preferable from the viewpoint of smooth operation. On the other hand, in the retraction structure of this embodiment, the retraction direction slope 51h is formed so that the retraction operation of the second group lens frame 6 can be executed even when the retraction is as close to the AF lens frame 51 as possible. Even with a relatively small amount of backward movement of the second group lens moving frame 8, the retracting cam surface 21c can be made into a reasonable shape, and both downsizing and smoothness of operation can be achieved. Further, the CD holder 21 is formed with a retracting direction inclined surface 21f that is continuous with the retracting direction inclined surface 51h of the AF lens frame 51, and the retracting direction inclined surface 21f functions in the same manner as the retracting direction inclined surface 51h. In the present embodiment, the AF lens frame 51 is a movable member in the optical axis direction. However, the above-described effect by the retraction direction inclined surface 51h is a type of lens mirror in which the member corresponding to the AF lens frame 51 does not move in the optical axis direction. It is also effective in a cylinder.
[0112]
As described above, in the retraction structure of the second group lens frame 6 of the present embodiment, in the state where the AF lens frame 51 has been moved to the rearward movement end (FIGS. 40 and 41), the second group lens frame 6 is retracted and retracted. It is designed not to interfere with the AF lens frame 51 even when the operation is performed. When the main switch is turned off, the control circuit 140 first drives the AF motor 160 to move the AF lens frame 51 to the rearward movement end. Controlled to move. However, if the AF lens frame 51 is not moved to the rearward moving end for some reason even if the main switch is turned off, it moves toward the retracted position while moving rearward in the optical axis direction together with the second group lens moving frame 8. There is a possibility that the AF lens frame 51 may overlap the movement locus of the second group lens frame 6 that is rotating (FIGS. 46 and 44).
[0113]
As a fail-safe structure, a rear projecting portion 6m projecting rearward in the optical axis direction than the second lens group LG2 is formed in the second group lens frame 6, and the front projecting cylindrical portion 51c of the AF lens frame 51 is formed. A rib-like front protrusion 51f that protrudes further forward than the third lens group LG3 is formed on the front end surface 51c1 at a position facing the rear protrusion 6m (FIGS. 40, 41, 44 to 44). (See FIG. 47). As shown in FIG. 47, the front protrusion 51f has a rear protrusion 6m (AF frame contact) when the second group lens frame 6 rotates from the shooting position to the retracted position in the plane direction orthogonal to the shooting optical axis Z1. It is formed in a region corresponding to the movement locus of the surface 6n).
[0114]
Therefore, even if the second lens group frame 6 is moved backward and retracted while the AF lens frame 51 does not move to the rearward moving end and is stopped at an incomplete retracted position, the front projecting portion 51f of the AF lens frame 51 does not move. On the other hand, since the AF frame contact surface 6n of the rear protrusion 6m always comes into contact first, there is no possibility that the second lens group LG2 contacts the AF lens frame 51 and is damaged. In other words, as shown in FIG. 47, the movement trajectory of the rear protrusion 6m does not overlap the third lens group LG3 at any angular position of the second group lens frame 6. There is no possibility that other parts of the frame 6 may come into contact with the third lens group LG3 and be damaged. The swing arm 6c is provided with the aforementioned FPC support protrusion 6s in parallel with the rear protrusion 6m. However, the rear protrusion 6m is more backward than the FPC support protrusion 6s. Therefore, the FPC support protrusion 6s does not come into contact with the third lens group LG3. With the above structure, the contact position between the second group lens frame 6 and the AF lens frame 51 is always limited to the rear projecting portion 6m and the front projecting portion 51f, and the optical performance of the second lens group LG2 and the third lens group LG3 is limited. There is no adverse effect. Further, the stopped AF lens frame 51 can be pushed backward by the second group lens frame 6 during the backward movement and retracting rotation pressing the front protrusion 51f via the rear protrusion 6m.
[0115]
While the AF frame contact surface 6n of the rear protrusion 6m is a plane orthogonal to the photographing optical axis Z1, as shown in FIGS. 45 and 46, the front surface of the front protrusion 51f is orthogonal to the photographing optical axis Z1. The inclined contact surface 51g is inclined by θ2 with respect to the flat surface. The inclined contact surface 51f gradually inclines backward in the optical axis direction as it advances in the direction in which the rear protrusion 6m moves (upward in FIGS. 45 to 47) when the second group lens frame 6 rotates in the retracting direction. Is formed. Unlike this, if the front surface of the front protrusion 51f is a surface parallel to the AF frame contact surface 6n, the sliding resistance increases when both surfaces come into contact with each other while the second group lens frame 6 is retracted and rotated. Therefore, the retraction rotation of the second group lens frame 6 may be hindered. On the other hand, by making the front surface of the front projecting portion 51f an inclined surface such as the inclined contact surface 51g, even when the second group lens frame 6 is retracted and rotated, it contacts the AF frame contact surface 6n. It is possible to reduce the sliding resistance and reliably retract. In the present embodiment, θ2 is set to 3 degrees as a desirable inclination angle.
[0116]
Further, although the rear projecting portion 6m and the front projecting portion 51f are not in contact with each other, when the AF lens frame 51 is not completely retracted, the retracting direction inclined surface 51h is placed on the rear end portion of the lens tube 6a (strictly, the group lens holding portion). It can be made to contact the lid 9) and function as a fail-safe surface similar to the inclined contact surface 51g.
[0117]
The lens retracting mechanism also moves the optical axis position of the second lens group LG2 in a plane direction orthogonal to the imaging optical axis Z1 when the optical axis of the second lens group LG2 does not coincide with the imaging optical axis Z1. Can be adjusted. Two types of optical axis position adjusting mechanisms are mounted, one of which is a position adjusting mechanism for the second group lens frame support plates 36 and 37 with respect to the second group lens moving frame 8, and this adjustment is performed by the first eccentric shaft member. This is performed by rotating the 34X and the second eccentric shaft member 34Y. The other is a contact position adjustment mechanism of the eccentric pin 35b with respect to the stopper arm 6e, and this adjustment is performed by rotating the rotation restricting pin 35.
[0118]
First, the position adjusting mechanism of the second group lens frame support plates 36 and 37 with respect to the second group lens moving frame 8 will be described. The support structure for the first eccentric shaft member 34X and the second eccentric shaft member 34Y has been described above. However, when it is repeated, as shown in FIGS. 28, 32 and 33, the front eccentric pin 34X-b of the first eccentric shaft member 34X is obtained. Is slidable in the longitudinal (major axis) direction of the first longitudinal hole 36a with respect to the first longitudinal hole 36a and immovably engaged in the width direction perpendicular to the longitudinal direction, and is a front eccentric pin 34Y-b is slidably engaged with the laterally long hole 36e in the longitudinal (long axis) direction of the laterally long hole 36e and immovably engaged in the width direction perpendicular to the longitudinal direction. The longitudinal direction of the first vertically long hole 36a and the longitudinal direction of the horizontally long hole 36e are orthogonal to each other. Hereinafter, the former parallel to the vertical direction of the camera is referred to as the Y direction, and the latter parallel to the horizontal direction of the camera is referred to as the X direction. .
[0119]
The long axis of the first vertically long hole 37 a formed in the rear second group lens frame support plate 37 is parallel to the long axis of the first long hole 36 a of the second group lens frame support plate 36. That is, the first vertically long hole 37a is a long hole long in the Y direction. The front and rear first vertical holes 36a and 37a are formed at positions where the second group lens frame support plates 36 and 37 face each other. Further, the long axis 37 e of the second group lens frame support plate 37 has a long axis parallel to the long axis of the horizontal hole 36 e of the second group lens frame support plate 36. That is, the laterally long hole 37e is a long hole that is long in the X direction. The front and rear horizontal holes 36e and 37e are formed at positions where the second group lens frame support plates 36 and 37 face each other. As shown in FIG. 29, the rear eccentric pin 34X-c engages the first vertically elongated hole 37a so as to be slidable in the Y direction and immovable in the X direction, like the front eccentric pin 34X-b. The front eccentric pin 34Y-b engages with the horizontally elongated hole 37e so as to be slidable in the X direction and immovable in the Y direction.
[0120]
Similarly to the first vertically long holes 36a and 37a and the horizontally long holes 36e and 37e, the second vertically long holes 36f and 37f have parallel long axes and are opposed to the second group lens frame support plates 36 and 37. Is formed. The second vertically elongated holes 36f and 37f are elongated holes in the Y direction parallel to the first vertically elongated holes 36a and 37a. The front boss 8j and the rear boss 8k projecting from the second lens group moving frame 8 are engaged with the second vertically elongated holes 36f and 37f so as to be slidable in the Y direction and immovable in the X direction. Yes.
[0121]
As shown in FIG. 31, the large diameter shaft portion 34X-a and the large diameter shaft portion 34Y-a are engaged with the eccentric shaft support hole 8f and the eccentric shaft support hole 8i so as not to move in the radial direction. Therefore, the first eccentric shaft member 34X rotates around the adjustment shaft PX that is the central axis of the large diameter shaft portion 34X-a, and the second eccentric shaft member 34Y is the central axis of the large diameter shaft portion 34Y-a. It rotates about the adjustment axis PY1. The front eccentric pin 34X-b and the rear eccentric pin 34X-c are each provided so as to be eccentric with respect to the adjustment shaft PX in the Y direction. As described above, the front eccentric pin 34X-b and the rear eccentric pin 34X-c are formed coaxially and with the same diameter. Further, the front eccentric pin 34Y-b and the rear eccentric pin 34Y-c protrude from the adjustment shaft PY1 in the X direction (see FIG. 33). The front eccentric pin 34Y-b and the rear eccentric pin 34Y-b The eccentric pin 34Y-c is also formed coaxially and with the same diameter.
[0122]
Therefore, when the second eccentric shaft member 34Y is rotated about the adjustment shaft PY1, the arc direction locus about the adjustment shaft PY1 and the Y-direction is generally in the Y direction with respect to the front eccentric pin 34Y-b and the rear eccentric pin 34Y-c. The movement force to is given. Since the front eccentric pin 34Y-b and the rear eccentric pin 34Y-c are engaged with the laterally long hole 36e and the laterally long hole 37e in a state where relative movement in the Y direction is restricted, the eccentric pins 34Y-b , 34Y-c are moved in the X direction in the respective laterally long holes 36e, 37e, and the moving force in the Y direction is transmitted to the second group lens frame support plate 36 and the second group lens frame support plate 37. Here, the remaining two first vertically long holes 36 a and second vertically long holes 36 f formed in the second group lens frame support plate 36 are long holes in the Y direction and remain formed in the second group lens frame support plate 37. Since the two first vertically long holes 37a and the second vertically long hole 37f are also long holes in the Y direction, the second group lens frame support plate 36 and the second group lens frame support plate 37 are projections ( The front eccentric pin 34X-b, the rear eccentric pin 34X-c, the front boss 8j, and the rear boss 8k) are guided and moved straight in the Y direction. As a result, the position of the second group lens frame 6 with respect to the second group lens movement frame 8 is displaced in the Y direction, and the optical axis of the second lens group LG2 is adjusted in the Y direction.
[0123]
  When the first eccentric shaft member 34X is rotated about the adjustment shaft PX, the arc of the center of the adjustment shaft PX in the X direction with respect to the front eccentric pin 34X-b and the rear eccentric pin 34X-c. Movement force is given. Since the front eccentric pin 34X-b and the rear eccentric pin 34X-c are engaged with the first longitudinal hole 36a and the first longitudinal hole 37a in a state in which relative movement in the X direction is restricted, While the pins 34X-b and 34X-c are moved in the Y direction within the first longitudinal holes 36a and 37a, the moving force in the X direction is applied to the second group lens frame support plate 36 and the second group lens frame support plate 37. Communicated. Here, the front eccentric pin 34Y-b and the rear eccentric pin 34Y-c can move in the X direction with respect to the laterally long hole 36e and the laterally long hole 37e, respectively. Since movement in the X direction is restricted with respect to the second vertically long hole 36f and the second vertically long hole 37f, the second group lens frame supporting plate 36 and the second group lens frame supporting plate 37 have the second vertically long hole 36f and the second long hole 36f. Centering on the lower end side having the vertically long hole 37fDoRockingTilt close to. thisTilt (oscillation approximate operation) is performed by the front eccentric pin 34Y of the second eccentric shaft member 34Y. - b and rear eccentric pin 34Y - The relative movement in the X direction of the horizontally elongated hole 36e and the horizontally elongated hole 37e with respect to c and the relative movement of the second vertically elongated hole 36f and the second vertically elongated hole 37f in the Y direction with respect to the front boss 8j and the rear boss 8k are combined. is there.The second group rotation shaft 33 supporting the second group lens frame 6 is,TheNear the engagement position of the front and rear bosses 8j and 8k and the second vertically elongated holes 36f and 37f, which are virtual centers of tiltingOf the second group lens frame support plate 36 and the second group lens frame support plate 37.The tiltCan be treated as approximating a linear movement in the X direction at the position of the second group rotation shaft 33. Therefore, the position of the second lens group LG2 changes in the X direction by the rotation of the first eccentric shaft member 34X.
[0124]
  In addition, as an optical axis adjustment mechanism using two eccentric shaft members, another form as shown in FIG. 50 is also possible. In the adjusting mechanism shown in FIG. 50, the front boss 8j and the rear boss 8k are engaged with an inclined long hole (moving guide means, third long hole) 36f ′ inclined with respect to both the Y direction and the X direction. , 37f ′. The inclined long holes 36f 'and 37f' are parallel to each other and formed at symmetrical positions in the optical axis direction. Since the inclined long holes 36f ′ and 37f ′ contain both components in the X direction and the Y direction, when the second eccentric shaft member 34Y is rotated in the structure, the inclined long holes 36f ′ and 37f ′ are inclined with respect to the front boss 8j and the rear boss 8k. The long holes 36f ′ and 37f ′ are slightly displaced in the X direction while moving in the Y direction. as a result,The second group lens frame support plate 36 and the second group lens frame support plate 37 areThe lower end portion having the inclined long holes 36f 'and 37f' is slightly in the X direction.DisplacementWhile lettingFront eccentric pin 34X of the first eccentric shaft member 34X - b and rear eccentric pin 34X - By changing the engagement position of the first vertically long holes 36a, 37a with respect to cMove in Y direction(Tilt). When the first eccentric shaft member 34X is rotated,The inclined long holes 36f ′ and 37f ′ move slightly in the Y direction while moving in the X direction with respect to the front boss 8j and the rear boss 8k, and the second group lens frame support plate 36 and the second group lens frame support plate 37 are The front eccentric pin 34Y of the second eccentric shaft member 34Y is slightly displaced in the Y direction in the vicinity of the lower end portion having the inclined long holes 36f 'and 37f'. - b and rear eccentric pin 34Y - By changing the engagement position of the horizontally elongated holes 36e and 37e with respect to cMove in the X direction(Tilt). By combining these two types of movements, the position of the second group lens frame 6 can be appropriately changed within a plane orthogonal to the optical axis.
[0125]
The optical axis adjustment of the second lens group LG2 by the first eccentric shaft member 34X and the second eccentric shaft member 34Y is performed with the support plate fixing screw 66 loosened, and when the adjustment is completed, the support plate fixing screw 66 is tightened. Then, the second group lens frame support plate 36 and the second group lens frame support plate 37 sandwich the front support plate mounting surface 8c and the rear support plate mounting surface 8e while maintaining the adjusted positional relationship, and the second group rotation shaft. 33 is also maintained at the adjusted position. Since the optical axis position of the second lens group LG2 is determined based on the second group rotation axis 33, the adjusted optical axis position is maintained as a result. As a result of the adjustment of the optical axis position, the support plate fixing screw 66 also moves together with the second group lens frame support plates 36 and 37. However, as shown in FIG. 31, the screw shaft portion 66a is located in the screw insertion hole 8h. It is loosely fitted with a margin so that the support plate fixing screw 66 and the second group lens moving frame 8 do not interfere with each other when the optical axis position is adjusted.
[0126]
As a mechanism for adjusting the position by moving the moving object two-dimensionally, a second stage capable of moving forward and backward in a linear direction orthogonal to the first stage that can move forward and backward in a specific linear direction is used. A type in which a stage is provided and a driving target is further supported thereon is known as a typical type. However, such a two-stage support structure has a drawback that the structure becomes complicated. On the other hand, the optical axis position adjusting mechanism of the lens barrel is two-dimensionally adjusted because each of the second group lens frame support plates 36 and 37 is supported so as to be movable in both the X direction and the Y direction. The mechanism could be realized with a simple structure. In addition, in the embodiment, in order to improve the support stability of the second group lens frame 6, a pair of second group lens frame support plates 36 and 37 that are separated from each other are provided. It is possible to support the second group lens frame 6 with only one of 36 and 37. In this case, the adjustment mechanism may be provided only for the one second group lens frame support plate.
[0127]
In the optical axis adjustment mechanism described above, the front eccentric pin 34X-b and the rear eccentric pin 34X-c of the first eccentric shaft member 34X, which serve as a reference for position adjustment of the second group lens frame support plate 36 and the second group lens frame support plate 37, are provided. Since the front eccentric pin 34Y-b and the rear eccentric pin 34Y-c of the second eccentric shaft member 34Y, and the front boss 8j and the rear boss 8k, which are paired in the front-rear direction, are formed coaxially in the front-rear direction, When the first eccentric shaft member 34X or the second eccentric shaft member 34Y is rotated, the front and rear second group lens frame support plate 36 and the second group lens frame support plate 37 are maintained in parallel with each other with the same locus (the same Move the same amount in the direction). For example, the second group lens frame support plate 36 and the second group lens frame support plate 37 are not affected by the rotation operation of either the front eccentric pin 34X-b or the rear eccentric pin 34X-c of the first eccentric shaft member 34X. The second group lens frame support plate moves evenly (same amount) in the X direction and rotates either the front eccentric pin 34Y-b or the rear eccentric pin 34Y-c of the second eccentric shaft member 34Y. The 36 and the second group lens frame support plate 37 move equally (the same amount) in the Y direction. As will be described later, in this embodiment, a rotational force is applied by a driver to the front eccentric pin 34X-b and the front eccentric pin 34Y-b on the second group lens frame support plate 36 side. The support plate 37 follows the second group lens frame support plate 36 without being kinked. Therefore, there is no possibility that the second group rotation shaft 33 is tilted during the optical axis adjustment, and the optical axis adjustment of the second lens group LG2 can be performed with high accuracy.
[0128]
In addition, the first eccentric shaft member 34X and the second eccentric shaft member 34Y are sandwiched between the second group lens frame support plate 36 and the second group lens frame support plate 37 that are spaced apart from each other at the front and rear positions sandwiching the shutter unit 76. The axial length of the second group rotating shaft 33 is secured to be long enough to be comparable to the length of the second group lens moving frame 8 in the optical axis direction. Accurate optical axis adjustment is achieved.
[0129]
Next, adjustment of the optical axis position of the second lens group LG2 based on the relationship between the stopper arm 6e and the eccentric pin 35b will be described. 29 and 30, the rotation restricting pin 35 engages the large diameter shaft portion 35a with the rotation restricting pin insertion hole 8m so as to be rotatable, and the eccentric pin 35b is connected to the rotation restricting pin. It protrudes to the rear of the insertion hole 8m. As shown in FIG. 27, the eccentric pin 35b is located on the movement locus of the stopper arm 6e. The eccentric pin 35b protrudes from the adjustment shaft PY2 passing through the center of the large-diameter shaft portion 35a at a position eccentric in the X direction (FIG. 34), and the rotation restricting pin 35 is centered on the adjustment shaft PY2. When rotated, the eccentric pin 35b is displaced in the Y direction. As described above, since the eccentric pin 35b is a member that determines the shooting position of the second group lens frame 6, when the eccentric pin 35b is displaced in the Y direction, the optical axis position of the second lens group LG2 at the shooting position results. Is moved in the Y direction. The adjustment of the optical axis position by the rotation restricting pin 35 can be used together with the adjustment by the second eccentric shaft member 34Y. In particular, the adjustment is performed as an auxiliary adjustment when the adjustment amount by the second eccentric shaft member 34Y is not sufficient. It is preferable to use the movement restriction pin 35.
[0130]
As shown in FIG. 28, the driver engaging recesses 34X-d, 34Y-d, and 35c in the first eccentric shaft member 34X, the second eccentric shaft member 34Y, and the rotation restricting pin 35 are all moved by the second group lens. It is exposed in front of the frame 8. Further, the driver engagement recess 66 b of the support plate fixing screw 66 is also exposed in front of the second group lens moving frame 8. Therefore, the optical axis position adjustment work of the second lens group LG2 is all performed from the front of the second group lens moving frame 8. On the other hand, the first outer cylinder 12 attached to the outside of the second group lens moving frame 8 is formed with an inner diameter flange 12c for supporting the lens barrier mechanism on the inner diameter side. The inner diameter flange 12c is formed by the first group retaining ring 3. At the same time, the front of the second lens group moving frame 8 is closed.
[0131]
As shown in FIG. 48 and FIG. 49, four circular driver insertion holes for exposing the driver engagement recesses 34X-d, 34Y-d, 35c and 66b to the front are formed in the inner diameter flange 12c of the first outer cylinder 12. (First to fourth rotation operation holes) 12d, 12e, 12f and 12g are formed penetrating in the optical axis direction. Further, in the first group retaining ring 3, portions overlapping these driver insertion holes 12d, 12e, 12f and 12g are also cut out in a circular shape. By forming these driver insertion holes 12d, 12e, 12f and 12g, the driver engagement recesses 34X-d, 34Y-d, 35c and 66b can be applied to any of the driver engagement recesses 34X with the first outer cylinder 12 attached. The driver can be engaged from the front. The driver insertion holes 12d, 12e, 12f and 12g are exposed by removing the barrier cover 101 and the above-described lens barrier mechanism located behind the barrier cover 101, and practically without disassembling the lens barrel components other than the lens barrier mechanism. The optical axis position of the second lens group LG2 can be adjusted with the camera completed. Therefore, even if a position error of the second lens group LG2 occurs during assembly, it can be easily adjusted in the final assembly process, and the workability is excellent.
[0132]
As described above, in the zoom lens barrel 71 of the embodiment, the length in the optical axis direction when stored can be extremely shortened compared to the conventional lens barrel. The specific structure 71 is an example in which the present invention can be implemented, and the technical idea of the present invention is not limited to the embodiment. For example, although the optical element to be retracted is the second lens group LG2 in the embodiment, the present invention can be used as the retracting optical element regardless of the lens group, or the aperture, shutter, low-pass filter, and the like. Further, although the embodiment is a zoom lens barrel, the present invention can be applied to a single focus lens barrel as long as the length of the barrel is shortened from the shooting state to the retracted state. Is also possible. Further, the embodiment is applied to a so-called digital still camera, but the present invention can also be applied to other optical devices.
[0133]
In the above-described embodiment, the position adjustment of the second lens group LG2 is performed by inserting a driver from the front of the lens barrel. However, the rear (imaging plane side) depends on the configuration of the lens barrel. When access from the side is easier, members corresponding to the eccentric shaft members 34X and 34Y, the rotation regulating pin 35, and the support plate fixing screw 66 may be rotated by an operation from the rear. In short, it is only necessary to improve the work efficiency by making these members related to the position adjustment of the retracting optical element all operable from the same direction.
[0134]
In the zoom lens barrel 71 of the embodiment, the rotation center axis 33 of the second group lens frame 6 is parallel to the imaging optical axis Z1, but the rotation center axis for retracting and rotating the retracting optical element and the imaging optical system. The present invention can also be applied to a lens barrel that is not parallel to the optical axis.
[0136]
【The invention's effect】
  As described above, according to the present invention, the retractable optical element can be adjusted in position with a simple structure, and all the operation members for adjusting the position can be operated from the same direction. Also excellentThe
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a zoom lens barrel to which the present invention is applied.
2 is an exploded perspective view of a portion related to a support mechanism for a first lens group in the zoom lens barrel of FIG. 1; FIG.
3 is an exploded perspective view of a portion related to a support mechanism for a second lens group in the zoom lens barrel of FIG. 1; FIG.
4 is an exploded perspective view of a portion related to a feeding mechanism from a fixed ring to a third outer cylinder in the zoom lens barrel of FIG. 1; FIG.
5 is a perspective view of a completed state in which a zoom motor and a finder unit are added to the zoom lens barrel of FIG. 1. FIG.
6 is a longitudinal sectional view of a camera equipped with the zoom lens barrel, showing a wide end and a tele end of the zoom lens barrel of FIG. 1. FIG.
7 is a longitudinal sectional view of the camera barrel storage state of FIG. 6;
FIG. 8 is a developed plan view of a stationary ring.
FIG. 9 is a developed plan view of a helicoid ring.
FIG. 10 is a developed plan view showing the components on the inner peripheral surface side of the helicoid ring as seen through.
FIG. 11 is a development plan view of a third outer cylinder.
FIG. 12 is a developed plan view of a straight guide ring.
FIG. 13 is a developed plan view of a cam ring.
FIG. 14 is a developed plan view seen through the second group guide cam groove on the inner peripheral surface side of the cam ring.
FIG. 15 is a developed plan view of a straight guide ring.
FIG. 16 is a development plan view of a second group lens moving frame.
FIG. 17 is a developed plan view of a second outer cylinder.
FIG. 18 is a developed plan view of the first outer cylinder.
FIG. 19 is a diagram conceptually illustrating a relationship between main members of the zoom lens barrel of the present embodiment.
FIG. 20 is an exploded perspective view of a second group lens frame support mechanism.
21 is a front perspective view of a state in which the support mechanisms of FIG. 20 are combined.
FIG. 22 is a rear perspective view of the same.
FIG. 23 is a rear perspective view showing a state in which the cam projection is being inserted into the cam projection insertion / removal opening of the rear two-group lens frame support plate.
FIG. 24 is a single front view of a second group lens moving frame.
FIG. 25 is a single perspective view of a second group lens moving frame.
FIG. 26 is a front perspective view of the second group lens moving frame in a state where the second group lens frame and the shutter unit are assembled.
FIG. 27 is a rear perspective view of the same.
FIG. 28 is a front view of the same.
FIG. 29 is a rear view of the same.
30 is a rear view showing a state in which the second group lens frame is retracted from the state of FIG. 29. FIG.
31 is a cross-sectional view taken along the line XXXI-XXXI in FIG.
32 is a front view showing the second group lens frame held at the photographing position in the state of FIG. 28 as seen through. FIG.
FIG. 33 is an enlarged front view showing a main part of an optical axis adjusting mechanism of a second lens group by first and second eccentric shaft members.
FIG. 34 is a front view showing an enlarged main part of an optical axis adjusting mechanism of a second lens group by a rotation restricting pin.
FIG. 35 is a front view showing the relationship between the second group lens frame held at the photographing position and the cam protrusion.
FIG. 36 is a front view showing a state in which the second group lens frame is rotated to the vicinity of the retracted position by the retracting cam surface of the cam protrusion.
FIG. 37 is a front view showing a state in which the second group lens frame is held at the retracted position by the retracted position holding surface of the cam protrusion.
FIG. 38 is a perspective view of the retracted AF lens frame and the CCD holder as viewed obliquely from below.
FIG. 39 is a front view of a CCD holder, an AF lens frame, and a second group lens moving frame.
FIG. 40 is a perspective view showing a state in which the second group lens frame is retracted to a position immediately before coming into contact with the cam protrusion.
FIG. 41 is a perspective view showing a state in which the second group lens frame is held in the retracted position and retracted to the rearward movement end.
FIG. 42 is a cross-sectional view showing an arrangement structure of an exposure control FPC board.
FIG. 43 is a perspective view showing an aspect of holding the exposure control FPC board by the second group lens frame.
44 is a perspective view showing a state in which the second group lens frame is close to the AF lens frame. FIG.
FIG. 45 is a side view showing a state immediately before the second group lens frame is brought into contact with the AF lens frame.
FIG. 46 is a side view showing a state in which the second group lens frame is abutted against the AF lens frame.
FIG. 47 is a front view showing the positional relationship between the movement locus of the second group lens frame and the AF lens frame.
FIG. 48 is a perspective view of the first outer cylinder covering the second group lens moving frame.
FIG. 49 is a front view of the same.
FIG. 50 is a front view showing a different embodiment of the optical axis adjusting mechanism of the second lens group by the first and second eccentric shaft members.
[Explanation of symbols]
LG1 first lens group (front optical element)
LG2 Second lens group (retraction optical element)
LG3 Third lens group (rear optical element)
LG4 Low-pass filter
S Shutter
A Aperture
Z0 Center tube center axis
Z1 Shooting optical axis
Z2 retracting optical axis
Z3 Optical axis of viewfinder objective
PX PY1 PY2 Adjustment axis
1 1-group lens frame
1a Male adjustment screw
1b Dept.
2 Group 1 adjustment ring
2a Female adjustment screw
2b Guide protrusion
2c engaging claw
3 Group 1 retaining ring
3a Spring receiving part
6 2 group lens frame (swing member, supported element)
6a Lens tube
6b Swing center tube
6c Swing arm
6d Oscillating shaft hole
6e Stopper arm
6f Front spring support
6g Rear spring support
6h 6i Spring protrusion
6j retracting arm
6k 6p Spring hook
6m rear protrusion
6n AF frame contact surface
6q Straight support surface
6r inclined support surface
6s FPC support protrusion
8 2 group lens moving frame (straight forward and backward movement, support)
8a 8a-W Straight guide groove
8b Cam follower for 2 groups
8b-1 Front cam follower
8b-2 Rear cam follower
8c Front support plate mounting surface (support plate fixing means)
8d Partial cylindrical part
8e Rear support plate mounting surface (support plate fixing means)
8f Eccentric shaft support hole
8g Swing center tube storage hole
8h Screw insertion hole
8i Eccentric shaft support hole
8j Front boss (moving guide means, fixed protrusion, protrusion)
8k rear boss (moving guide means, fixed protrusion, protrusion)
8m rotation restriction pin insertion hole
8n penetration space
8p keyway
8q Lens tube entry recess
8r Stopper arm entry recess
8s Intermediate flange
8t 2 group lens moving aperture
9 2 group lens holding lid
10 Group 2 straight guide ring
10a Crotch process
10b Ring part
10c 10c-W Straight guidance key
10d FPC through hole
11 Cam ring
11a 2 group guide cam groove
11a-1 Front cam groove
11a-2 Rear cam groove
11b 1st group guide cam groove
11c 11e Circumferential groove
11d Barrier drive ring pressing surface
12 First outer cylinder (outer cylinder)
12a Engagement protrusion
12b Group 1 adjusting ring guide groove
12c inner diameter flange
12d Driver insertion hole (first or second rotation operation hole)
12e Driver insertion hole (third rotation operation hole)
12f Driver insertion hole (fourth rotation operation hole)
12g Driver insertion hole (first or second rotation operation hole)
13 Second outer cylinder
13a Straight running guide protrusion
13b Straight guide groove
13c Inner diameter flange
14 Straight guide ring
14a Straight ahead guide protrusion
14b Relative rotation guide protrusion
14c Relative rotation guide protrusion
14d circumferential groove
14e Roller guide through groove
14e-1 Circumferential groove
14e-2 Circumferential groove
14e-3 Lead groove
14f First straight guide groove
14g Second straight guide groove
15 Third outer cylinder
15a Rotation transmission protrusion
15b Mating protrusion
15c Spring bearing recess
15d Relative rotation guide protrusion
15e Circumferential groove
15f Roller fitting groove
17 Roller bias spring
17a Roller pressing piece
18 Helicoid ring
18a male helicoid
18b Rotating sliding protrusion
18c spur gear
18d Rotation transmission recess
18e Fitting recess
18f Spring insertion recess
18g circumferential groove
21 CCD holder
21a Cam protrusion (position control mechanism)
21b Movement restriction surface
21c Retraction cam surface
21d Retraction position holding surface
21e Guide key
21f Retreat direction slope
22 Fixed ring
22a Female helicoid
22b Straight guide groove
22c Lead groove
22d Rotating sliding groove
22e Stopper insertion / removal hole
22f Annular part
22g 22h Notch
24 Group 1 biasing spring
25 Separating direction biasing spring
26 Lens barrel stopper
28 Zoom gear
29 Zoom gear shaft
30 Finder gear
31 Roller for 1 group
32 Cam ring roller
32a Roller fixing screw
33 2nd group rotation axis (rotation center axis)
33a Flange
34X first eccentric shaft member (first eccentric shaft member)
34X-a Large diameter shaft
34X-b Front eccentric pin
34X-c Rear eccentric pin
34X-d Driver engagement recess (rotation operation part)
34Y Second eccentric shaft member (second eccentric shaft member)
34Y-a Large diameter shaft
34Y-b Front eccentric pin
34Y-c Rear eccentric pin
34Y-d Driver engagement recess (rotation operation part)
35 Rotation restriction pin (position control mechanism, third eccentric shaft member)
35a Large diameter shaft
35b Eccentric pin
35c Driver engagement recess (rotation operation part)
36 37 2 group lens frame support plate (shaft support plate, support plate)
36a 37a First vertically long hole (first long hole)
36b 37b Rotating shaft fitting hole
36c 37c Cam protrusion insertion / removal opening
36d 37d Screw screw hole (support plate fixing means)
36e 37e Horizontal slot (second slot)
36f 37f Second vertically long hole (moving guide means, third long hole)
36f '37f' inclined long hole (moving guide means, third long hole)
36g Spring hook
37g Guide key entry groove
38 Axial pressure spring
39 2nd lens frame return spring (position control mechanism)
39a Front spring end
39b Rear spring end
40 Rotation transmission spring
40a Fixed spring end
40b Movable spring end
51 AF lens frame (3 group lens frame)
51a 51b Guide hole
51c Front protruding cylindrical part
51c1 Tip surface
51c2 opening
51c3 51c4 51c5 51c6 Side
51d 51e Guide arm
51f Front protrusion
51g inclined contact surface
51h Retreat direction slope
52 53 AF guide shaft
54 AF nut
55 AF frame biasing spring
60 CCD (solid-state image sensor)
61 Packing
62 CCD base plate
64 Stop ring fixing screw
66 Support plate fixing screw (support plate fixing means)
66a Screw shaft
66b Driver engagement recess (rotation operation part)
70 Digital camera
71 Zoom lens barrel
72 Camera body
73 Filter holder
74 Reduction gear box
75 Lens drive control FPC board
76 Shutter unit
77 Exposure control FPC board
77a First linear portion
77b U-shaped part
77c Second linear portion
77d Third linear portion
80 Finder unit
81a Objective window
81b 81c Movable variable magnification lens
81d prism
81e eyepiece
81f eyepiece window
82 Guide shaft
101 Barrier cover
102 Barrier holding plate
103 Barrier drive ring
104 105 Barrier blade
106 Barrier biasing spring
107 Barrier drive ring biasing spring
140 Control circuit
150 Zoom motor
160 AF motor

Claims

A plurality of optical elements constituting the imaging optical system;
A rectilinear advance / retract ring that is guided straight in the optical axis direction of the photographic optical system and retracts in the image plane direction when the photographing state is changed to the retracted state;
A swinging member that supports a retracting optical element that forms a part of the plurality of optical elements and is rotatably supported by a rotation center shaft provided inside the linear advance / retreat ring;
In the photographing state, the swinging optical member is held while the retracting optical element is positioned on the same optical axis as the other optical elements, and is rotated when the swinging member is retracted in the retracting direction together with the rectilinear advancement and retraction. A position control mechanism for retracting the retracting optical element to a position different from the optical axis of the other optical elements;
A pair of shaft support plates spaced in the direction of the optical axis, supporting the front and rear end portions of the rotation center shaft by sandwiching the rectilinear advance / retract ring from the front and rear;
A support plate fixing means for fixing the pair of shaft support plates to a straight advancement / retraction ring and permitting movement in a direction perpendicular to the optical axis in the unlocked state;
A pair having a pair of first long holes formed at the opposing positions of the pair of shaft support plates so that their long axes are parallel to each other, and a long axis perpendicular to the long axis of the first long holes A second slot of
Each is slidably engaged with the pair of first elongated holes inserted and supported so as to be rotatable about an axis parallel to the optical axis with respect to an eccentric shaft support hole provided in the straight advance / retreat ring. A first eccentric shaft member having a pair of eccentric pins at both ends; a second eccentric shaft member having a pair of eccentric pins slidably engaged with the pair of second elongated holes; Moving guide means for restricting the moving direction of each shaft support plate in a plane orthogonal to the optical axis when the first and second eccentric shaft members are rotated, provided on the shaft support plate and the linear advance and retreat ring;
The first and second elongated holes in at least one of the shaft support plates are through holes in the optical axis direction, a pair of eccentric pins at both ends of the first eccentric shaft member, and a second eccentric shaft member Among the pair of eccentric pins at both ends, a rotation operation portion that can be rotated from the front or rear opening portion of the straight advance / retreat ring is provided at an end portion that engages with the through hole. Optical element retraction mechanism for lens barrel.

In the optical element retracting mechanism of the lens barrel according to claim 1, the rotation operation portions of the first and second eccentric shaft members are formed on the front eccentric pin side opposite to the storage direction,
An outer cylinder that covers the outside of the rectilinear advance / retreat ring and that has an inner diameter flange positioned in front of the rectilinear advance / retreat ring; An optical element retracting mechanism for a lens barrel in which first and second rotation operation holes are formed in front of the rotation operation unit and penetrate in the optical axis direction.

3. The optical element retracting mechanism for a lens barrel according to claim 1 or 2, wherein the support plate fixing means includes a screw screw hole formed through a pair of shaft support plates in the optical axis direction, and the screw screw connection. A common fixing screw that is screwed into the hole at the same time,
The fixing screw is a lens barrel optical element retraction mechanism in which an end portion facing in the same direction as the rotation operation portion of the first and second eccentric shaft members is a rotation operation portion that can be rotated.

3. The optical element retracting mechanism for a lens barrel according to claim 2, wherein the support plate fixing means includes a screw screw hole formed through a pair of shaft support plates in the optical axis direction, and a screw screw hole. A common fixing screw that is screwed at the same time, and the fixing screw has a rotation operation portion that can be rotated at the front end opposite to the storage direction,
An inner diameter flange of the outer cylinder is a lens barrel optical element retraction mechanism having a third rotation operation hole that is positioned in front of the rotation operation portion of the fixed screw and penetrates in the optical axis direction.

5. The lens barrel optical element retraction mechanism according to claim 1, wherein a pivot center axis of the swinging member is parallel to an optical axis of the photographing optical system, and the position control mechanism includes:
A biasing means for biasing the swing member in the rotation direction;
An eccentric pin that is supported by the linear advance and retreat ring so as to be rotatable at a rotation center parallel to the optical axis and is eccentric with respect to the rotation center is engaged with the swing member to determine a rotation end in the biasing direction. A third eccentric shaft member different from the first and second eccentric shaft members;
And the third eccentric shaft member is a lens barrel having a rotation operation section that can be rotated at the end facing in the same direction as the rotation operation sections of the first and second eccentric shaft members. Optical element retraction mechanism.

5. The optical element retracting mechanism for a lens barrel according to claim 4, wherein the pivot center axis of the swing member is parallel to the optical axis of the photographing optical system, and the position control mechanism is
Urging means for urging the swinging member in the rotation direction;
An eccentric pin that is supported by the linear advance and retreat ring so as to be rotatable at a rotation center parallel to the optical axis and is eccentric with respect to the rotation center is engaged with the swing member to determine a rotation end in the biasing direction. A third eccentric shaft member different from the first and second eccentric shaft members;
The third eccentric shaft member has a rotation operation portion that can be rotated at the front end opposite to the storage direction,
An inner diameter flange of the outer cylinder is an optical element retracting mechanism of a lens barrel having a fourth rotation operation hole that is located in front of the rotation operation portion of the third eccentric shaft member and penetrates in the optical axis direction.

7. The optical element retracting mechanism for a lens barrel according to claim 2 , further comprising a detachable lens barrier mechanism at a front portion of an inner diameter flange of the outer cylinder, wherein the lens barrier mechanism is used to An optical element retracting mechanism of a lens barrel in which the rotation operation hole is covered.

The optical element retracting mechanism for a lens barrel according to any one of claims 2 , 4, 6, and 7 , wherein the outer cylinder supports a front optical element positioned in front of the retracting optical element, so An optical element retracting mechanism for the lens barrel that moves backward and forward when the storage operation is performed.

9. The optical element retracting mechanism for a lens barrel according to claim 1, wherein the rotation operation unit is a concave part that can be engaged with a driver.

The optical element retracting mechanism of the lens barrel according to any one of claims 1 to 9, further comprising a rear optical element positioned behind the retracting optical element in a photographing state, and in the retracted state, the retracting optical element is An optical element retracting mechanism of a lens barrel that is positioned by overlapping the rear optical element and the optical axis direction position.

11. The optical element retracting mechanism for a lens barrel according to claim 1, wherein the retracting optical element is a lens barrel that is a lens group.

A plurality of optical elements constituting the imaging optical system;
A rectilinear advance / retract ring that is guided straight in the optical axis direction of the photographic optical system and retracts in the image plane direction when the photographing state is changed to the retracted state;
A pair of shaft support plates that sandwich the straight advance / retract ring from the front and the rear and that are spaced apart in the optical axis direction;
A swinging member that supports a retracting optical element that forms a part of the plurality of optical elements, and is rotatably supported by the rotation center axis inside the rectilinear advance / retreat ring;
In the photographing state, the swinging optical member is held while the retracting optical element is positioned on the same optical axis as the other optical elements, and is rotated when the swinging member is retracted in the retracting direction together with the rectilinear advancement and retraction. A position control mechanism for retracting the retracting optical element to a position different from the optical axis of the other optical elements;
A pair having a pair of first long holes formed at the opposing positions of the pair of shaft support plates so that their long axes are parallel to each other, and a long axis perpendicular to the long axis of the first long holes A second slot of
Each is slidably engaged with the pair of first elongated holes inserted and supported so as to be rotatable about an axis parallel to the optical axis with respect to an eccentric shaft support hole provided in the straight advance / retreat ring. A first eccentric shaft member having a pair of eccentric pins at both ends; a second eccentric shaft member having a pair of eccentric pins slidably engaged with the pair of second elongated holes; The shaft support plate is screwed through in the optical axis direction and fixed to the linear advance / retract ring. In the unlocked state, the shaft support plate is moved in a direction orthogonal to the optical axis in accordance with the rotation of the first and second eccentric shaft members. A fixed screw allowing movement of the pair of shaft support plates;
Have
A lens barrel characterized in that the first and second eccentric shaft members and the fixed screw can be operated to rotate at their front and rear ends in the same direction from the front or rear opening of the rectilinear advance / retreat ring. Optical element retracting mechanism.

The optical element retracting mechanism of the lens barrel according to claim 12, wherein a pivot center axis of the swing member is parallel to an optical axis of the photographing optical system, and the position control mechanism is
Urging means for urging the oscillating member in the rotation direction;
An eccentric pin that is supported by the linear advance and retreat ring so as to be rotatable at a rotation center parallel to the optical axis and is eccentric with respect to the rotation center is engaged with the swing member to determine a rotation end in the biasing direction. A third eccentric shaft member different from the first and second eccentric shaft members;
And the third eccentric shaft member has a rotation operation section that can be rotated at the end in the same direction as the rotation operation sections of the first and second eccentric shaft members. Element evacuation mechanism.