JP4074800B2

JP4074800B2 - Lens barrel, camera, image projection apparatus, lens holding frame, camera, and optical apparatus

Info

Publication number: JP4074800B2
Application number: JP2002276366A
Authority: JP
Inventors: 茂入沢
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2002-09-20
Filing date: 2002-09-20
Publication date: 2008-04-09
Anticipated expiration: 2022-09-20
Also published as: JP2004117398A

Description

【０００１】
【発明の属する技術分野】
本発明は複数組の撮影レンズを個別に進退させることにより焦点距離を異ならせるようにしたズームレンズ鏡筒の改良に関し、特に撮影レンズを保持したレンズ保持枠をカム部材のカム溝に係合させるカムフォロアの支持構造の改良に関するものである。
【０００２】
【従来の技術】
近年、撮影レンズの焦点距離が最短であるときの広角状態と、最長であるときの望遠状態とを選択的に切り替えることができるズームレンズ鏡胴等の可変焦点装置を備えたカメラが普及している。この種のカメラとしては、例えばデジタルカメラ、ビデオカメラ、銀塩カメラ等が知られている。
ところで、この種の可変焦点装置を備えたカメラに対するユーザーのニーズは多岐に渡ってきており、特にカメラ形状の小型化と、撮影画角の広画角化が強く求められている。このニーズに合わせるために、ズームレンズ鏡胴の小型化、広画角化が進んでいる。
ズームレンズ鏡胴は、回転自在に支持された円筒状のカム部材の内部に光軸方向に沿って複数組の撮影レンズを軸方向へ独立して進退自在に支持した構成を備えている。具体的には、各撮影レンズ（群）を支持する各レンズ保持枠の外周から外径方向へ突設させたカムフォロアを、カム部材の内周面に形成した光軸と斜行する複数のカム溝（螺旋溝）内に夫々係合させることにより、カム部材の回転に伴って各カムフォロアが光軸方向へ移動するように構成されている。
このようにカム部材によりレンズ保持枠を光軸方向に移動するズームレンズ鏡胴において、レンズ保持枠に対してカムフォロアを組付ける従来の構造としては、例えばレンズ保持枠とカムフォロアとを一体成型する構造、レンズ保持枠に設けられた光軸と直交する穴内にカムフォロアを圧入する構造、レンズ保持枠に光軸と直交する方向にカムフォロアをネジ止めする構造、又はカムフォロアを接着する構造、等々が採用されてきた。
特開２０００−１３１５８９公報（特許文献１）には、レンズ保持枠に嵌入されるカムフォロアの軸部にエッジ部（フランジ部）を形成し、カムフォロアに抜け方向や倒れ方向への力が作用した時に前記エッジ部が前記レンズ保持枠に食い込むことにより前記軸部の抜けを防止したカムフォロアとレンズ鏡胴を開示している。
【特許文献１】
特開２０００−１３１５８９公報
【０００３】
【発明が解決しようとする課題】
しかし、特許文献１に記載のカムフォロアとレンズ保持枠との接合構造では、小型化や組み立て方法の関係で、接合部の接合面積を大きくすることに限界があり、レンズ保持枠に外力や衝撃を受けた場合に、その力はレンズ保持枠とカムフォロアの限られた接合面積に作用し、レンズ保持枠またはカムフォロアの変形が発生し、レンズ保持枠に対しカムフォロアが傾く、レンズ保持枠よりカムフォロアが脱落する、などの問題が発生する。
本発明は上記に鑑みてなされたものであり、小型化されてカムフォロアを支持する部位の面積が極限されているレンズ保持枠に対して、十分な接合面積、接合強度を確保しつつカムフォロアを組み付けることができる接合構造を備えたレンズ鏡胴、これを備えたカメラ、画像投影装置を提供することを課題とする。
【０００４】
【課題を解決するための手段】
上記課題を解決するため、本発明は、レンズを保持して光軸方向に移動する複数のレンズ保持枠と、各レンズ保持枠を夫々個別に光軸方向へ進退可能に支持すると共に各レンズ保持枠の光軸を中心とした回転を禁止する固定側のライナー部材と、該ライナー部材の外周面に沿って回転自在に配置されると共に光軸に対して斜行する複数のカム溝を備えたカム部材と、前記各レンズ保持枠の外周部に夫々取り付けられて前記カム部材の各カム溝に係合してガイドされることによりカム部材の回転時に各レンズ保持枠を夫々光軸方向に進退させるカムフォロアと、を備えたレンズ鏡胴において、前記カムフォロア又は前記レンズ保持枠の何れか一方には、光軸方向へ延びる凸形状部が設けられ、他方には該凸形状部に嵌合する凹形状部が形成されており、前記凸形状部に対して前記凹形状部を光軸方向にスライドさせて嵌合させることにより、前記カムフォロアを前記レンズ保持枠に取り付けたことを特徴とする。
レンズ鏡胴が衝撃を受けた際に、内蔵されたレンズ保持枠とカム部材のカム溝とを連結するカムフォロアが、レンズ保持枠に対して十分な強度にて固定されていることは重要である。しかし、小型化されたレンズ保持枠とカムフォロアとの接合強度を十分に確保することは容易ではない。本発明では、カム溝と係合するカムフォロアの軸方向と直交する光軸方向に延びる突条（凸形状部）と、この突条にスライド結合する溝（凹形状部）とから成る接合部を設けることにより、レンズ保持枠とカムフォロアとの接合面積を大きくしたので、衝撃力を分散することができ、レンズ保持枠に対するカムフォロアの傾き、脱落を防止することが可能となる。突条、溝ともに、十分な長さを有するように構成し、両者の接合面積を大きくした点が特徴的である。
【０００５】
本発明は、レンズを保持して光軸方向に移動する複数のレンズ保持枠と、各レンズ保持枠を夫々個別に光軸方向へ進退可能に支持すると共に各レンズ保持枠の光軸を中心とした回転を禁止する固定側のライナー部材と、該ライナー部材の外周面に沿って回転自在に配置されると共に光軸に対して斜行する複数のカム溝を備えたカム部材と、前記各レンズ保持枠の外周部に夫々取り付けられて前記カム部材の各カム溝に係合してガイドされることによりカム部材の回転時に各レンズ保持枠を夫々光軸方向に進退させるカムフォロアと、を備えたレンズ鏡胴において、前記カムフォロアは、前記カム溝と係合するカムフォロア本体と、該カムフォロア本体を支持するカムフォロア基部と、を備え、前記カムフォロア基部又は前記レンズ保持枠の何れか一方の光軸方向一端面には光軸方向へ延びる凹形状部を備え、他方には該凹形状部に嵌合する凸形状部が設けられ、前記凹形状部に対して前記凸形状片を光軸方向にスライドさせて嵌合させることにより、前記カムフォロア基部を前記レンズ保持枠に取り付けたことを特徴とする。
レンズ保持枠、或いはカムフォロアの何れか一方に設けた周方向への溝部（凹形状部）と、他方に設けた差込片（凸形状部）とを嵌合させるようにしたので、レンズ保持枠とカムフォロアの接合面面積を大きくし、衝撃力を分散しカムフォロアの傾き、脱落の発生防止することができる。
本発明は、前記カムフォロアと前記レンズ保持枠とを接着により接合したことを特徴とする。
カムフォロアとレンズ保持枠の凹凸接合部を接着剤により接合することにより、カムフォロアとレンズ保持枠との相対位置関係を調整変更した後に接合することが可能となる。
【０００６】
本発明は、前記カムフォロアは、前記ライナー部材の光軸方向ガイドスリットと係合することにより、回転を禁止されつつ光軸方向への移動を許容されることを特徴とする。
カムフォロアにライナー部材と摺動自在に係合する部位を設けることにより、レンズ保持枠にライナー部材と係合する部位を設ける必要をなくし、レンズ保持枠形状を簡素化し加工を容易にすることができる。
本発明は、前記カムフォロアは、少なくとも、別部材としての、前記カム溝と係合するカムフォロア本体と、該カムフォロア本体を支持するカムフォロア基部と、を連結した構成を備えていることを特徴とする。
カムフォロアを、カム溝に係合するカムフォロア本体と、レンズ保持枠に接合するカムフォロア基部との２部品から構成したので、両部品を材質、特性の異なる任意の材質にすることが可能となり、作動性、加工性をよくすることができる。
本発明は、前記レンズ保持枠と前記カムフォロアとの光軸方向の相対位置関係を調整することにより、各レンズ保持枠により保持されたレンズ間隔、ピント位置を調整することを特徴とする。
レンズ保持枠に対するカムフォロアの光軸方向の取付け位置を変位させることにより、レンズ群間隔、ピント位置の調整を格別な調整機構を設けることなく実現できる。
本発明は、前記カムフォロアと前記レンズ保持枠は、何れか一方の材質が金属材料であり、他方の材質が樹脂材料であることを特徴とする。
カムフォロアとレンズ保持枠の材質を、一方は金属材料で、他方を樹脂材料にすることにより強度、外観品質、作動特性などを向上することができる。
本発明は、前記カムフォロアと前記レンズ保持枠との接合部は、弾性応力を用いた接合構造であることを特徴とする。
カムフォロアとレンズ保持部材の接合を弾性応力を用いた接合構造とすることにより、組み立てを簡便にすることができる。
【０００７】
本発明は、前記弾性応力を用いた接合構造は、圧入によるものであることを特徴とする。
弾性応力を用いた手段を圧入にすることにより、接合部形状を簡略化でき、組み立てを簡便にすることができる。
本発明は、前記レンズ保持枠と前記カムフォロアの回転方向の相対位置関係を変位させることにより、画像品質を調整する構成を備えたことを特徴とする。
レンズ保持枠と、カムフォロアの光軸を中心とした回転方向の相対位置を変位させて画像品質を調整することにより、別に調整機構を設けることなく調整を可能にすることができる。
本発明は、前記のレンズ鏡胴を備えたことを特徴とする。
これによれば、上記各請求項に記載の優れた作用効果を奏するレンズ鏡胴を搭載したカメラを提供することができる。
本発明の画像投影装置は、前記レンズ鏡胴を備えたことを特徴とする。
これによれば、上記各請求項に記載の優れた作用効果を奏するレンズ鏡胴を搭載した画像投影装置を提供することができる。
【０００８】
【発明の実施の形態】
以下、本発明を図面に示した実施の形態により詳細に説明する。
なお、以下に示す実施の形態は一例に過ぎず、本発明の技術的範囲を限定的に解釈する要素とはならない。
図１（ａ）（ｂ）及び（ｃ）は本発明の一実施形態に係るレンズ鏡胴を適用したデジタルカメラの鏡胴組み立て状態の外観斜視図、分解斜視図、及び要部構成図である。
このレンズ鏡胴１は、カメラ本体側のベース枠２に組み付けられ、更にベース枠２側に設けた駆動機構３によってレンズ鏡胴１を構成する各可動部材を駆動するように構成されている。
レンズ鏡胴１は、第１及び第２の撮影レンズ（群）を夫々保持して光軸方向に移動する第１及び第２のレンズ保持枠１１、２１と、各レンズ保持枠１１、２１を夫々個別に光軸方向へ進退可能に支持すると共に各レンズ保持枠の光軸を中心とした回転を禁止するためにベース枠２にネジ等によって固定された円筒状のライナー部材３１と、ライナー部材３１の外周面に沿って回転自在に配置されると共に光軸に対して斜行する複数のカム溝を備えたカム部材４１と、各レンズ保持枠１１、２１の外周部に夫々取り付けられてカム部材４１の各カム溝４３に係合してガイドされることによりカム部材４１の回転時に各レンズ保持枠１１、２１を夫々光軸方向に進退させるカムフォロア５１、５２と、両レンズ保持枠１１、２１間に配置されて両者を光軸方向に付勢するコイルバネ５５と、第１のレンズ枠２１の前面側から取り付けられるカバー６０と、を備えている。
ライナー部材３１の円筒状部分には軸方向へ延びる光軸方向ガイドスリット３１ａが周方向に所定のピッチで複数本（この例では３本）形成されており、各レンズ保持枠１１、２１の外周部から外径方向へ夫々突出するカムフォロア５１、５２は各光軸方向ガイドスリット３１ａを介して外径方向へ突出し、ライナー部材３１の外径側に同心円状に配置された円筒状のカム部材４１の内周面に設けた複数のカム溝４３と夫々カム係合している。各カム溝４３は、カム部材４１の光軸方向に対して斜行する方向へ延びる溝であり、螺旋状に構成されている。つまり、各カムフォロア５１、５２がライナー部材３１の光軸方向ガイドスリット３１ａ内に嵌合することによって両レンズ保持枠１１、２１により支持された各レンズは、回転方向への動きを禁止される一方で、光軸方向への直進動作を許容される。
更に、各カムフォロア５１、５２がカム部材４１のカム溝４３内にカム係合することによって、カム部材４１が駆動機構３によって回転駆動されたときに各レンズ保持枠１１、２１は、回転することなく光軸方向へ直線的に進退することができる。
駆動機構３は、ベース枠２に取り付けられたカム駆動手段としてのズームモータ７０と、ズーム減速系７１と、フォーカスモータ７５等を備えている。ズームモータ７０からの駆動力はズーム減速系７１を介してカム部材４１の一端外周に設けたギヤに伝達されてこれを回転駆動する。ズーム減速系７１によりカム部材４１を正逆回動することにより、第１及び第２のレンズ保持枠１１、２１を光軸方向に進退させ、ズーム、収納動作を行う。
ズーム駆動位置の検出は、フォトインタラプタ７２によって、ズーム減速系７１の軸の一つに取り付けられたズーム遮光羽７３を検出し、この検出結果に基づいてズームモータ７０の回転量を検出することにより行なわれる。
なお、フォーカス駆動は、図示しない第３の撮影レンズを、フォーカスモータ７５と不図示の減速手段によって駆動することにより実現され、フォーカス駆動位置の検出は位置検出手段によって行われる。
【０００９】
次に、図２（ａ）及び（ｂ）は第１のレンズ保持枠１１にカムフォロア５１を組み付けた状態を示す斜視図、及び分解斜視図、図３はカムフォロアがライナー部材３１とカム部材４１に係合した状態の断面図、図４は第１のレンズ保持枠にカバーを取り付けた状態を後方から見た図である。
第１のレンズ保持枠１１は後端縁に所定の周方向ピッチにて複数のカムフォロア装着用の張り出し片１２を突設し、各張り出し片１２の後端縁中央部には切欠き状の凹所１２ａが形成されている。凹所１２ａの対向し合う２つの内周縁には光軸方向へ延びる突条（凸形状部）１２ｂが形成されている。
一方、カムフォロア５１は、カム部材４１の内周面のカム溝４３と係合するカムフォロア本体５１ａと、カムフォロア本体５１ａを支持するカムフォロア基部５１ｂと、を備えている。カムフォロア本体５１ａとカムフォロア基部５１ｂとは、予め一体成形されてもよいし、別部材としての両者を結合一体化した構成としてもよい。基部５１ｂの対向し合う２つの外壁には、第１のレンズ保持枠１１の凹所１２ａ内に設けた突条１２ｂとスライド係合する溝（凹形状部）５１ｂ−１を光軸方向へ向けて設ける。
図２（ｂ）に示した如き位置関係で、凹所１２ａの開口側から光軸方向に向けてカムフォロア５１の基部５１ｂを差し込んで、溝部５１ｂ−１を突条１２ｂにスライド装着することができる。この際、接着剤により両者を接合してもよいし、溝部５１ｂ−１内と突条１２ｂを弾性的な圧着力によって固定してもよい。後者の場合、溝部５１ｂ−１と突条１２ｂのうちの少なくとも何れか一方を樹脂等の弾性材料にて構成して、その弾性力を利用して圧着を実現する。このようにカムフォロア基部５１ｂとレンズ保持枠５１との接合部を、弾性応力を用いた接合構造とすることにより、螺子止め、接着等を用いずに簡易に固定することが可能となる。
或いはまた、溝部５１ｂ−１内に突条１２ｂを圧入することにより、強固な固定を実現してもよい。つまり、弾性応力を利用した圧入を行うことにより、接合部形状を簡略化することができ、組み立て作業を簡便に行うことが可能となる。
【００１０】
図３の断面図に示すように、カムフォロアの本体５１ａをカム部材４１のカム溝４３内に摺動自在に嵌合させる一方で、カムフォロア基部５１ｂの上部に位置するキー面５１ｂ−２をライナー部材３１の光軸方向ガイドスリット３１ａ内にスライド自在に係合させる。このため、レンズ保持枠にライナー部材と係合する部位を設ける必要をなくし、レンズ保持枠形状を簡素化し加工を容易にすることができる。
また、レンズ保持枠１１とカムフォロア５１との光軸方向の相対位置関係を任意に調整することにより、各レンズ保持枠５１、５２により夫々保持されたレンズ間隔、ピント位置を調整することが可能である。即ち、突条１２ｂに対する溝５１ｂ−１の位置関係は、凹所１２ａの最奥部まで基部５１ｂを差込んで固定する必要はなく、凹所２１ａ内におけるカムフォロア５１の光軸方向位置は微調整可能であり、微調整する結果、レンズ間隔、ピント位置を微調整することが可能となる。
なお、上記実施形態では、第１のレンズ保持枠１１側に設けた切欠き状の凹所１２ａ内に光軸方向へ延びる突条１２ｂを形成し、これと凹凸嵌合する溝５１ｂ−１をカムフォロア側に設けたが、これと逆に凹所１２ａ内に光軸方向へ延びる溝を設けると共に、カムフォロアの基部外周に溝と嵌合する突条を設けても良い。
また、カムフォロア５１とレンズ保持枠１１（特に、張り出し片１２）は、何れか一方の材質を金属材料とし、他方の材質を樹脂材料とすることにより、機械的強度、耐久性、外観品質、作動特性を向上することができる。
次に、第２のレンズを保持する第２のレンズ保持枠２１に取り付けられたカムフォロア５２は、カム部材４１のカム溝４３内に嵌合する円筒状のカムフォロア本体５２ａと、第２のレンズ保持枠２１の外周面に所定の周方向ピッチにて形成した支持孔２１ａに圧入固定される固定軸５２ｂと、を備えている。カムフォロア本体５２ａは、その中間部にてライナー部材３１の光軸方向ガイドスリット３１ａにも遊嵌する。
第１のレンズ保持枠１１と第２のレンズ保持枠１２の軸方向間隔は、第１のレンズ保持枠１１に対するカムフォロア５１の光軸方向位置を調整することにより、変更可能となる。
カバー６０は、環状のカバー本体６１と、カバー本体６１の裏面から後方へ延びる脚部６２とからなり、脚部６２を第１のレンズ保持枠１１の前部開口から差し込むことにより、固定可能となる。
【００１１】
次に、図５（ａ）及び（ｂ）は本発明のレンズ鏡胴に用いる第１のレンズ保持枠及びカムフォロアの他の実施形態の外観斜視図、及びＡ−Ａ断面図である。
この第１のレンズ保持枠８１は、図１に示したレンズ保持枠１１に代えてレンズ鏡胴１に適用されるものである。
第１のレンズ（群）Ｌを内部に保持した円筒状の第１のレンズ保持枠８１は、円筒状の本体８２と、本体８２内壁から内径方向へ延びてレンズＬの外周を保持する保持部８３と、保持部８３から後方へ延び且つ本体８２の後端縁８２ａの内壁との間に溝部（凹形状部）８４を形成する張り出し片８５と、を備えている。この張り出し片８５及び溝部８４は、周方向全長、又は周方向に所定のピッチ（例えば、１２０度間隔）にて配置される。図示の例では、周方向全長にわたって張り出し片８５と溝部８４が形成されているが、周方向全長にわたらない所定の周方向長と、光軸方向長を有する構成でもよい。この溝部８４内にカムフォロア９１を支持する。溝部８４は、光軸を中心とした円形、或いは円弧形状である。
カムフォロア９１は、カム部材４１に設けたカム溝４３（図３参照）と係合するカムフォロア本体９２と、カムフォロア本体９２を支持するカムフォロア基部９３と、を備えている。
カムフォロア基部９３は、その前面に溝部８４内に嵌合可能な寸法、形状を有した差込片（凸形状部）９３ａを有する環状体であり、径方向に所定のピッチにて延びる穴９３ｂを有する。差込片９３ａを溝部８４内に差込み固定することにより、位置決め固定を行い、穴９３ｂ内にカムフォロア本体９２の一部（小径部）を差し込むことによりカムフォロア９１を固定する。
溝部８４と差込片９３ａとの固定、穴９３ｂとカムフォロア本体９２との固定は、弾性結合、圧入、接着等、任意の方法を採用できる。
カムフォロア本体９２とカムフォロア基部９３とは、樹脂、金属等の同一材料であっても良いし、一方を樹脂、他方を金属としてもよい。この場合には、強度、外観品質、作動特性を向上することができる。
【００１２】
また、レンズ保持枠８１とカムフォロア９１との光軸方向の相対位置関係を任意に調整することにより、各レンズ保持枠８１、５２により夫々保持されたレンズ間隔、ピント位置を調整することが可能である。即ち、溝部８４に対する差込片９３ａの光軸方向位置関係（差込深さ）は、溝部８４の最奥部まで差込片９３ａを密着させて固定する必要はなく、溝部８４内におけるカムフォロア９１の光軸方向位置は微調整可能であり、微調整する結果、レンズ間隔、ピント位置を微調整することが可能となる。
更に、レンズ保持枠８１とカムフォロア９１の回転方向の相対位置関係を変位させることにより、画像品質を調整することが可能となる。即ち、溝部８４内における差込片９３ａの周方向位置は任意に調整可能であるため、溝部８４に対するカムフォロア９１の周方向位置を微調整できる。
なお、上記実施形態では、レンズ保持枠８１側に溝部８４を設け、カムフォロア９１側に差込片９３ａを設けたが、これとは逆に、カムフォロア９１側に溝部を設け、レンズ保持枠８１側に差込片を設けても良い。
なお、上記各実施形態では、いずれも第１の撮影レンズを保持した第１のレンズ保持枠１１、８１に対するカムフォロア５１、９１の結合構造についてのみ説明したが、第２のレンズ保持枠２１とカムフォロア５２との関係についても適用することができる。
なお、本発明に係るレンズ鏡胴１は、デジタルカメラ、銀塩カメラ、画像投影装置等、ズームレンズ鏡胴を備えるべき光学機器に適用することができる。
【００１３】
【発明の効果】
以上のように本発明によれば、撮影レンズを保持した複数のレンズ保持枠を光軸方向へ進退自在に支持したレンズ鏡胴において、小型化されたことによってカムフォロアを支持する部位の面積が極限されているレンズ保持枠に対して、十分な接合面積、接合強度を確保しつつカムフォロアを組み付けることができる接合構造を備えたレンズ鏡胴、これを備えたカメラ、画像投影装置を提供することを課題とする。
即ち、本発明によれば、カム溝と係合するカムフォロアの軸方向と直交する光軸方向に延びる突条（凸形状部）と、この突条にスライド結合する溝（凹形状部）とから成る接合部を設けることにより、レンズ保持枠とカムフォロアとの接合面積を大きくしたので、衝撃力を分散することができ、レンズ保持枠に対するカムフォロアの傾き、脱落を防止することが可能となる。
本発明によれば、レンズ保持枠、或いはカムフォロアの何れか一方に設けた周方向への溝部（凹形状部）と、他方に設けた差込片（凸形状部）とを嵌合させるようにしたので、レンズ保持枠とカムフォロアの接合面面積を大きくし、衝撃力を分散しカムフォロアの傾き、脱落の発生防止することができる。
本発明によれば、カムフォロアとレンズ保持枠の凹凸接合部を接着剤により接合することにより、カムフォロアとレンズ保持枠との相対位置関係を調整変更した後に接合することが可能となる。
本発明によれば、カムフォロアにライナー部材と摺動自在に係合する部位を設けることにより、レンズ保持枠にライナー部材と係合する部位を設ける必要をなくし、レンズ保持枠形状を簡素化し加工を容易にすることができる。
本発明によれば、カムフォロアを、カム溝に係合するカムフォロア本体と、レンズ保持枠に接合するカムフォロア基部との２部品から構成したので、両部位を材質、特性の異なる任意の材質にすることが可能となり、作動性、加工性をよくすることができる。
請求項６の発明によれば、レンズ保持枠に対するカムフォロアの光軸方向の取付け位置を変位させることにより、レンズ群間隔、ピント位置の調整を格別な調整機構を設けることなく実現できる。
【００１４】
本発明によれば、カムフォロアとレンズ保持枠の材質を、一方は金属材料で、他方を樹脂材料にすることにより強度、外観品質、作動特性などを向上することができる。
本発明によれば、カムフォロアとレンズ保持部材の接合を弾性応力を用いた接合構造とすることにより、組み立てを簡便にすることができる。
本発明によれば、弾性応力を用いた手段を圧入にすることにより、接合部形状を簡略化でき、組み立てを簡便にすることができる。
本発明によれば、レンズ保持枠と、カムフォロアの光軸を中心とした回転方向の相対位置を変位させて画像品質を調整することにより、別に調整機構を設けることなく調整を可能にすることができる。
本発明に係るカメラによれば、上記各請求項に記載の優れた作用効果を奏するレンズ鏡胴を搭載したカメラを提供することができる。
本発明に係る画像投影装置によれば、上記各請求項に記載の優れた作用効果を奏するレンズ鏡胴を搭載した画像投影装置を提供することができる。
【図面の簡単な説明】
【図１】（ａ）（ｂ）及び（ｃ）は本発明の一実施形態に係るレンズ鏡胴を適用したデジタルカメラの鏡胴組み立て状態の外観斜視図、分解斜視図、及び要部構成図。
【図２】（ａ）及び（ｂ）は第１のレンズ保持枠にカムフォロアを組み付けた状態を示す斜視図、及び分解斜視図。
【図３】カムフォロアがライナー部材とカム部材に係合した状態の断面図。
【図４】第１のレンズ保持枠にカバーを取り付けた状態を後方から見た図。
【図５】（ａ）及び（ｂ）は本発明の他の実施形態に係る鏡胴の構成図。
【符号の説明】
１レンズ鏡胴、２ベース枠、３駆動機構、１１、２１第１及び第２のレンズ保持枠、３１ライナー部材、３１ａ光軸方向ガイドスリット、４１カム部材、４３カム溝、５１、５２カムフォロア、５５コイルバネ、１２張り出し片、１２ａ凹所、１２ｂ凸形状部（突条）、５１ａカムフォロア本体、５１ｂカムフォロア基部、５１ｂ−１凹形状部（溝部）、６０カバー、６１カバー本体、６２脚部、７０ズームモータ、７１ズーム減速系、７５フォーカスモータ、８１第１のレンズ保持枠、８２本体、８２ａ後端縁、８３保持部、８４凹形状部（溝部）、８５張り出し片、９１カムフォロア、９２カムフォロア本体、９３カムフォロア基部、９３ａ凸形状部（差込片）、９３ｂ穴[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a zoom lens barrel in which focal lengths are made different by moving a plurality of sets of photographing lenses individually, and in particular, a lens holding frame holding a photographing lens is engaged with a cam groove of a cam member. The present invention relates to an improvement of a cam follower support structure.
[0002]
[Prior art]
In recent years, cameras equipped with a variable focus device such as a zoom lens barrel capable of selectively switching between a wide-angle state when the focal length of the photographing lens is the shortest and a telephoto state when the focal length is the longest have become widespread. Yes. As this type of camera, for example, a digital camera, a video camera, a silver salt camera, and the like are known.
By the way, the user needs for a camera equipped with this type of variable focus device are diversified. In particular, there is a strong demand for downsizing of the camera shape and widening of the field of view. In order to meet this need, zoom lens barrels are becoming smaller and wider in field of view.
The zoom lens barrel has a configuration in which a plurality of sets of photographing lenses are supported in a freely movable manner in the axial direction along an optical axis direction inside a cylindrical cam member that is rotatably supported. Specifically, a plurality of cams that are inclined with respect to the optical axis formed on the inner peripheral surface of the cam member are cam followers that project outward from the outer periphery of each lens holding frame that supports each photographing lens (group). Each cam follower is configured to move in the optical axis direction with the rotation of the cam member by being engaged with each other in the groove (spiral groove).
In the zoom lens barrel in which the lens holding frame is moved in the optical axis direction by the cam member as described above, as a conventional structure for assembling the cam follower to the lens holding frame, for example, a structure in which the lens holding frame and the cam follower are integrally molded A structure in which a cam follower is press-fitted into a hole perpendicular to the optical axis provided in the lens holding frame, a structure in which the cam follower is screwed in a direction perpendicular to the optical axis, a structure in which the cam follower is bonded, etc. are employed. I came.
Japanese Patent Laid-Open No. 2000-131589 (Patent Document 1) discloses that when an edge portion (flange portion) is formed on a shaft portion of a cam follower that is inserted into a lens holding frame, A cam follower and a lens barrel are disclosed in which the edge portion bites into the lens holding frame to prevent the shaft portion from coming off.
[Patent Document 1]
JP 2000-131589 A
[0003]
[Problems to be solved by the invention]
However, in the joint structure of the cam follower and the lens holding frame described in Patent Document 1, there is a limit to increasing the joint area of the joint due to the downsizing and the assembly method, and external force and impact are applied to the lens holding frame. When this occurs, the force acts on the limited joint area between the lens holding frame and cam follower, causing the lens holding frame or cam follower to deform, causing the cam follower to tilt relative to the lens holding frame, and the cam follower to fall off from the lens holding frame. Problems occur.
The present invention has been made in view of the above, and attaches a cam follower while securing a sufficient joining area and joining strength to a lens holding frame that is downsized and has a limited area for supporting a cam follower. It is an object of the present invention to provide a lens barrel having a joint structure that can be used, a camera including the lens barrel, and an image projection apparatus.
[0004]
[Means for Solving the Problems]
To solve the above problem, The present invention Is a lens holding frame that moves in the optical axis direction while holding the lens, and supports each lens holding frame so as to be able to advance and retreat individually in the optical axis direction, and rotate around the optical axis of each lens holding frame A fixed-side liner member that prohibits the rotation, a cam member that is rotatably arranged along the outer peripheral surface of the liner member, and includes a plurality of cam grooves that are inclined with respect to the optical axis, and each of the lens holding frames And a cam follower that respectively attaches to and is guided by engaging with each cam groove of the cam member to move each lens holding frame forward and backward in the optical axis direction when the cam member rotates. In the barrel, either one of the cam follower or the lens holding frame is provided with a convex shape portion extending in the optical axis direction, and the other is formed with a concave shape portion that fits into the convex shape portion. Front to convex part By fitting Slide the concave portion in the optical axis direction, characterized in that fitted with the cam follower on the lens holding frame.
When the lens barrel is impacted, it is important that the cam follower that connects the built-in lens holding frame and the cam groove of the cam member is fixed to the lens holding frame with sufficient strength. . However, it is not easy to secure sufficient bonding strength between the downsized lens holding frame and the cam follower. In the present invention, a joining portion comprising a ridge (convex shape portion) extending in the optical axis direction orthogonal to the axial direction of the cam follower engaged with the cam groove and a groove (concave shape portion) slidably coupled to the ridge is provided. By providing, the joint area between the lens holding frame and the cam follower is increased, so that the impact force can be dispersed, and the cam follower can be prevented from being tilted or dropped off from the lens holding frame. It is characteristic that both the protrusion and the groove are configured to have a sufficient length, and the joint area between the two is increased.
[0005]
The present invention Is a lens holding frame that moves in the optical axis direction while holding the lens, and supports each lens holding frame so as to be able to advance and retreat individually in the optical axis direction, and rotate around the optical axis of each lens holding frame A fixed-side liner member that prohibits the rotation, a cam member that is rotatably arranged along the outer peripheral surface of the liner member, and includes a plurality of cam grooves that are inclined with respect to the optical axis, and each of the lens holding frames And a cam follower that respectively attaches to and is guided by engaging with each cam groove of the cam member to move each lens holding frame forward and backward in the optical axis direction when the cam member rotates. In the cylinder, the cam follower includes a cam follower main body that engages with the cam groove, and a cam follower base that supports the cam follower main body, and one of the cam follower base and the lens holding frame. The one end surface in the optical axis direction is provided with a concave shape portion extending in the optical axis direction, and the other is provided with a convex shape portion that fits into the concave shape portion. The cam follower base is attached to the lens holding frame by sliding in the axial direction and fitting.
The lens holding frame or cam follower is fitted with a circumferential groove (concave portion) provided on the other side and an insertion piece (convex shape portion) provided on the other side. It is possible to increase the joint surface area of the cam follower, disperse the impact force, and prevent the cam follower from tilting or falling off.
The present invention Is characterized in that the cam follower and the lens holding frame are bonded together.
By joining the concave and convex joints between the cam follower and the lens holding frame with an adhesive, it becomes possible to join after adjusting and changing the relative positional relationship between the cam follower and the lens holding frame.
[0006]
The present invention The cam follower is allowed to move in the optical axis direction while being prohibited from rotating by engaging with the guide slit of the liner member in the optical axis direction.
By providing the cam follower with a portion that slidably engages with the liner member, it is not necessary to provide the lens holding frame with a portion that engages with the liner member, and the shape of the lens holding frame can be simplified and processing can be facilitated. .
The present invention The cam follower includes at least a cam follower main body that engages with the cam groove and a cam follower base that supports the cam follower main body as separate members.
The cam follower is composed of two parts: a cam follower body that engages with the cam groove and a cam follower base that is joined to the lens holding frame. , Workability can be improved.
The present invention The lens spacing and the focus position held by each lens holding frame are adjusted by adjusting the relative positional relationship between the lens holding frame and the cam follower in the optical axis direction.
By displacing the mounting position of the cam follower in the optical axis direction with respect to the lens holding frame, adjustment of the lens group interval and the focus position can be realized without providing a special adjustment mechanism.
The present invention One of the cam follower and the lens holding frame is a metal material, and the other material is a resin material.
Strength, appearance quality, operating characteristics, etc. can be improved by using a cam follower and a lens holding frame, one of which is a metal material and the other a resin material.
The present invention The joining portion between the cam follower and the lens holding frame is a joining structure using elastic stress.
By assembling the cam follower and the lens holding member with a joining structure using elastic stress, assembly can be simplified.
[0007]
The present invention The bonding structure using the elastic stress is based on press-fitting.
By press-fitting means using elastic stress, the joint shape can be simplified and assembly can be simplified.
The present invention The lens holding frame and the cam follower are configured to adjust the image quality by displacing the relative positional relationship in the rotation direction.
By adjusting the image quality by displacing the relative positions of the lens holding frame and the cam follower in the rotation direction about the optical axis, the adjustment can be performed without providing a separate adjustment mechanism.
The present invention Is provided with the lens barrel described above.
According to this, the camera carrying the lens barrel which has the outstanding effect described in the above-mentioned claims can be provided.
Of the present invention The image projection device Said A lens barrel is provided.
According to this, it is possible to provide an image projection apparatus equipped with a lens barrel that exhibits the excellent effects described in the above claims.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
Note that the embodiment described below is merely an example, and is not an element for limiting the technical scope of the present invention.
1A, 1B, and 1C are an external perspective view, an exploded perspective view, and a main configuration diagram of a lens barrel assembled state of a digital camera to which a lens barrel according to an embodiment of the present invention is applied. .
The lens barrel 1 is assembled to a base frame 2 on the camera body side, and is further configured to drive each movable member constituting the lens barrel 1 by a drive mechanism 3 provided on the base frame 2 side.
The lens barrel 1 holds first and second photographing lenses (groups) and moves in the direction of the optical axis, respectively. Holding frames 11, 21 And each lens Holding frames 11, 21 A cylindrical liner member 31 fixed to the base frame 2 by screws or the like to support the lens individually and removably in the optical axis direction and prohibit rotation of the lens holding frames around the optical axis; A cam member 41 provided with a plurality of cam grooves which are rotatably arranged along the outer peripheral surface of the member 31 and which are inclined with respect to the optical axis, and each lens Holding frames 11, 21 Each lens is attached to the outer periphery of the cam member 41 and engaged with each cam groove 43 of the cam member 41 so as to be guided. Holding frames 11, 21 Cam followers 51 and 52 for moving the lens forward and backward in the optical axis direction, and both lenses Holding frames 11, 21 A coil spring 55 disposed between them and biasing them in the optical axis direction, and a cover 60 attached from the front side of the first lens frame 21 are provided.
A plurality of (three in this example) optical axis guide slits 31a extending in the axial direction are formed in the cylindrical portion of the liner member 31 at a predetermined pitch in the circumferential direction. Holding frames 11, 21 The cam followers 51 and 52 projecting from the outer peripheral portion in the outer diameter direction respectively project in the outer diameter direction through the respective optical axis direction guide slits 31a, and are cylindrical cams arranged concentrically on the outer diameter side of the liner member 31. Cam engagement is performed with a plurality of cam grooves 43 provided on the inner peripheral surface of the member 41. Each cam groove 43 is a groove extending in a direction oblique to the optical axis direction of the cam member 41, and is formed in a spiral shape. In other words, the cam followers 51 and 52 are fitted into the optical axis direction guide slit 31 a of the liner member 31, so that both lenses Holding frames 11, 21 Each of the lenses supported by is allowed to move straight in the optical axis direction while being prohibited from moving in the rotational direction.
Furthermore, each cam follower 51, 52 is cam-engaged in the cam groove 43 of the cam member 41, so that each lens when the cam member 41 is rotationally driven by the drive mechanism 3. Holding frames 11, 21 Can advance and retract linearly in the direction of the optical axis without rotating.
The drive mechanism 3 includes a zoom motor 70 as cam drive means attached to the base frame 2, a zoom reduction system 71, a focus motor 75, and the like. The driving force from the zoom motor 70 is transmitted to a gear provided on the outer periphery of one end of the cam member 41 via the zoom reduction system 71 to drive the rotation. By rotating the cam member 41 forward and backward by the zoom deceleration system 71, the first and second lenses Holding frames 11, 21 Is moved forward and backward in the direction of the optical axis to perform zooming and storing operations.
The zoom drive position is detected by detecting the zoom shading blade 73 attached to one of the axes of the zoom decelerating system 71 by the photo interrupter 72 and detecting the rotation amount of the zoom motor 70 based on the detection result. Done.
The focus drive is realized by driving a third photographic lens (not shown) by a focus motor 75 and a speed reducer (not shown), and the focus drive position is detected by the position detector.
[0009]
Next, FIGS. 2A and 2B are a perspective view and an exploded perspective view showing a state in which the cam follower 51 is assembled to the first lens holding frame 11, and FIG. 3 shows the cam follower on the liner member 31 and the cam member 41. FIG. 4 is a cross-sectional view of the engaged state, and FIG. 4 is a view of the state where the cover is attached to the first lens holding frame as viewed from the rear.
The first lens holding frame 11 has a plurality of cam follower mounting protrusions 12 protruding from the rear end edge at a predetermined circumferential pitch, and a notch-shaped recess at the center of the rear end edge of each protrusion piece 12. A location 12a is formed. A ridge (convex shape) 12b extending in the optical axis direction is formed at two opposing inner peripheral edges of the recess 12a.
On the other hand, the cam follower 51 includes a cam follower main body 51a that engages with the cam groove 43 on the inner peripheral surface of the cam member 41, and a cam follower base 51b that supports the cam follower main body 51a. The cam follower main body 51a and the cam follower base 51b may be integrally formed in advance, or may be configured such that both of them as separate members are combined and integrated. On two opposing outer walls of the base 51b, a groove (concave portion) 51b-1 slidably engaged with the protrusion 12b provided in the recess 12a of the first lens holding frame 11 is directed in the optical axis direction. Provide.
With the positional relationship shown in FIG. 2B, the groove 51b-1 can be slidably mounted on the protrusion 12b by inserting the base 51b of the cam follower 51 in the optical axis direction from the opening side of the recess 12a. . At this time, both may be joined by an adhesive, or the inside of the groove 51b-1 and the protrusion 12b may be fixed by an elastic pressure bonding force. In the latter case, at least one of the groove 51b-1 and the ridge 12b is made of an elastic material such as a resin, and the pressure bonding is realized using the elastic force. As described above, the joining portion between the cam follower base portion 51b and the lens holding frame 51 has a joining structure using elastic stress, so that it can be easily fixed without using screwing or bonding.
Or you may implement | achieve firm fixation by press-fitting the protrusion 12b in the groove part 51b-1. That is, by performing press-fitting using elastic stress, the shape of the joint can be simplified, and the assembling work can be easily performed.
[0010]
Sectional view of FIG. Shown in As described above, the cam follower main body 51a is slidably fitted into the cam groove 43 of the cam member 41, while the key surface 51b-2 located at the upper portion of the cam follower base 51b is inserted into the guide slit in the optical axis direction of the liner member 31. It is slidably engaged in 31a. For this reason, it is not necessary to provide a portion for engaging the liner member in the lens holding frame, and the shape of the lens holding frame can be simplified and processing can be facilitated.
Further, by arbitrarily adjusting the relative positional relationship between the lens holding frame 11 and the cam follower 51 in the optical axis direction, it is possible to adjust the lens interval and the focus position held by the lens holding frames 51 and 52, respectively. is there. That is, the positional relationship of the groove 51b-1 with respect to the protrusion 12b does not require the base 51b to be inserted and fixed to the innermost part of the recess 12a, and the optical axis direction position of the cam follower 51 in the recess 21a is finely adjusted. As a result of fine adjustment, the lens interval and focus position can be finely adjusted.
In the above embodiment, the ridge 12b extending in the optical axis direction is formed in the notch-like recess 12a provided on the first lens holding frame 11 side, and the groove 51b-1 for engaging with this is formed. Although provided on the cam follower side, on the contrary, a groove extending in the optical axis direction may be provided in the recess 12a, and a protrusion that fits into the groove may be provided on the outer periphery of the base of the cam follower.
Further, the cam follower 51 and the lens holding frame 11 (particularly, the overhanging piece 12) are made of a metal material as one material and a resin material as the other material, so that the mechanical strength, durability, appearance quality, operation The characteristics can be improved.
Next, the cam follower 52 attached to the second lens holding frame 21 that holds the second lens includes a cylindrical cam follower main body 52a that fits in the cam groove 43 of the cam member 41, and a second lens holding. A fixed shaft 52b that is press-fitted into a support hole 21a formed at a predetermined circumferential pitch on the outer peripheral surface of the frame 21. The cam follower main body 52a is also loosely fitted in the optical axis direction guide slit 31a of the liner member 31 at an intermediate portion thereof.
The axial distance between the first lens holding frame 11 and the second lens holding frame 12 can be changed by adjusting the position of the cam follower 51 in the optical axis direction with respect to the first lens holding frame 11.
The cover 60 includes an annular cover body 61 and leg portions 62 extending rearward from the back surface of the cover body 61, and can be fixed by inserting the leg portions 62 from the front opening of the first lens holding frame 11. Become.
[0011]
Next, FIGS. 5A and 5B are an external perspective view and an AA cross-sectional view of another embodiment of the first lens holding frame and cam follower used in the lens barrel of the present invention.
The first lens holding frame 81 is applied to the lens barrel 1 instead of the lens holding frame 11 shown in FIG.
A cylindrical first lens holding frame 81 that holds the first lens (group) L therein has a cylindrical main body 82 and a holding portion that extends from the inner wall of the main body 82 in the inner diameter direction and holds the outer periphery of the lens L. 83 and a projecting piece 85 that extends rearward from the holding portion 83 and forms a groove (concave portion) 84 between the inner wall of the rear end edge 82a of the main body 82. The projecting pieces 85 and the groove portions 84 are arranged at a predetermined length (for example, at an interval of 120 degrees) in the entire circumferential direction or in the circumferential direction. In the illustrated example, the projecting piece 85 and the groove 84 are formed over the entire length in the circumferential direction, but a configuration having a predetermined circumferential length that does not extend over the entire circumferential length and a length in the optical axis direction may be used. A cam follower 91 is supported in the groove 84. The groove portion 84 has a circular shape or a circular arc shape around the optical axis.
The cam follower 91 includes a cam follower main body 92 that engages with a cam groove 43 (see FIG. 3) provided in the cam member 41, and a cam follower base portion 93 that supports the cam follower main body 92.
The cam follower base portion 93 is an annular body having an insertion piece (convex shape portion) 93a having a size and a shape that can be fitted in the groove portion 84 on the front surface, and has holes 93b extending at a predetermined pitch in the radial direction. Have. Positioning and fixing are performed by inserting and fixing the insertion piece 93a into the groove portion 84, and the cam follower 91 is fixed by inserting a part (small diameter portion) of the cam follower main body 92 into the hole 93b.
For fixing the groove portion 84 and the insertion piece 93a and fixing the hole 93b and the cam follower main body 92, any methods such as elastic coupling, press-fitting, and adhesion can be adopted.
The cam follower main body 92 and the cam follower base 93 may be made of the same material such as resin or metal, or one may be resin and the other may be metal. In this case, strength, appearance quality, and operating characteristics can be improved.
[0012]
Further, by arbitrarily adjusting the relative positional relationship between the lens holding frame 81 and the cam follower 91 in the optical axis direction, it is possible to adjust the lens interval and the focus position held by the lens holding frames 81 and 52, respectively. is there. That is, the optical axis direction positional relationship (insertion depth) of the insertion piece 93a with respect to the groove portion 84 does not require the insertion piece 93a to be in close contact with and fixed to the innermost portion of the groove portion 84, and the cam follower 91 in the groove portion 84 is fixed. The position in the optical axis direction can be finely adjusted. As a result of fine adjustment, the lens interval and the focus position can be finely adjusted.
Furthermore, it is possible to adjust the image quality by displacing the relative positional relationship between the lens holding frame 81 and the cam follower 91 in the rotational direction. That is, since the circumferential position of the insertion piece 93a in the groove 84 can be arbitrarily adjusted, the circumferential position of the cam follower 91 relative to the groove 84 can be finely adjusted.
In the above embodiment, the groove portion 84 is provided on the lens holding frame 81 side and the insertion piece 93a is provided on the cam follower 91 side. On the contrary, the groove portion is provided on the cam follower 91 side and the lens holding frame 81 side is provided. You may provide an insertion piece in.
In each of the above embodiments, only the coupling structure of the cam followers 51 and 91 to the first lens holding frames 11 and 81 holding the first photographing lens has been described. However, the second lens holding frame 21 and the cam follower are described. The relationship with 52 can also be applied.
The lens barrel 1 according to the present invention can be applied to an optical apparatus that should be equipped with a zoom lens barrel, such as a digital camera, a silver salt camera, and an image projection apparatus.
[0013]
【The invention's effect】
As described above, according to the present invention, in the lens barrel that supports the plurality of lens holding frames holding the photographing lens so as to be able to advance and retreat in the optical axis direction, the area of the portion that supports the cam follower is limited by being downsized. To provide a lens barrel having a joining structure capable of assembling a cam follower while securing a sufficient joining area and joining strength with respect to a lens holding frame, a camera provided therewith, and an image projection device. Let it be an issue.
That is, According to the present invention, By providing a joint composed of a ridge (convex shape portion) extending in the optical axis direction perpendicular to the axial direction of the cam follower engaged with the cam groove, and a groove (concave shape portion) slidably coupled to the ridge, Since the joining area between the lens holding frame and the cam follower is increased, it is possible to disperse the impact force and to prevent the cam follower from tilting and falling off from the lens holding frame.
According to the present invention, The lens holding frame or cam follower is fitted with a circumferential groove (concave portion) provided on the other side and an insertion piece (convex shape portion) provided on the other side. It is possible to increase the joint surface area of the cam follower, disperse the impact force, and prevent the cam follower from tilting or falling off.
According to the present invention, By joining the concave and convex joints between the cam follower and the lens holding frame with an adhesive, it becomes possible to join after adjusting and changing the relative positional relationship between the cam follower and the lens holding frame.
According to the present invention, By providing the cam follower with a portion that slidably engages with the liner member, it is not necessary to provide the lens holding frame with a portion that engages with the liner member, and the shape of the lens holding frame can be simplified and processing can be facilitated. .
According to the present invention, The cam follower is composed of two parts: a cam follower body that engages with the cam groove and a cam follower base that is joined to the lens holding frame. Therefore, both parts can be made of any material with different materials and characteristics. , Workability can be improved.
According to the invention of claim 6, by adjusting the mounting position of the cam follower in the optical axis direction with respect to the lens holding frame, adjustment of the lens group interval and the focus position can be realized without providing a special adjustment mechanism.
[0014]
According to the present invention, Strength, appearance quality, operating characteristics, etc. can be improved by using a cam follower and a lens holding frame, one of which is a metal material and the other a resin material.
According to the present invention, By assembling the cam follower and the lens holding member with a joining structure using elastic stress, assembly can be simplified.
According to the present invention, By press-fitting means using elastic stress, the joint shape can be simplified and assembly can be simplified.
According to the present invention, By adjusting the image quality by displacing the relative positions of the lens holding frame and the cam follower in the rotation direction about the optical axis, the adjustment can be performed without providing a separate adjustment mechanism.
According to the present invention According to the camera, it is possible to provide a camera equipped with a lens barrel that exhibits the excellent effects described in the above claims.
According to the present invention According to the image projecting device, it is possible to provide an image projecting device equipped with a lens barrel that exhibits the excellent effects described in the above claims.
[Brief description of the drawings]
FIGS. 1A, 1B, and 1C are an external perspective view, an exploded perspective view, and a main part configuration diagram of a lens barrel assembled state of a digital camera to which a lens barrel according to an embodiment of the present invention is applied. .
FIGS. 2A and 2B are a perspective view and an exploded perspective view showing a state in which a cam follower is assembled to a first lens holding frame.
FIG. 3 is a cross-sectional view of a state in which a cam follower is engaged with a liner member and a cam member.
FIG. 4 is a rear view of a state where a cover is attached to a first lens holding frame.
5A and 5B are configuration diagrams of a lens barrel according to another embodiment of the present invention. FIG.
[Explanation of symbols]
1 lens barrel, 2 base frame, 3 drive mechanism, 11, 21 1st and 2nd lens holding frame, 31 liner member, 31a optical axis direction guide slit, 41 cam member, 43 cam groove, 51, 52 cam follower, 55 coil spring, 12 projecting piece, 12a recess, 12b convex part ( Ridge), 51a cam follower main body, 51b cam follower base, 51b-1 concave shape portion (groove), 60 cover, 61 cover main body, 62 leg, 70 zoom motor, 71 zoom reduction system, 75 focus motor, 81 first Lens holding frame, 82 body, 82a rear edge, 83 holding portion, 84 concave shape portion (groove portion), 85 projecting piece, 91 cam follower, 92 cam follower body, 93 cam follower base portion, 93a convex shape portion (insertion piece), 93b hole

Claims

A plurality of lens holding frames that hold the lens and move in the optical axis direction, and support each lens holding frame individually so as to be able to advance and retract in the optical axis direction, and prohibit rotation of each lens holding frame around the optical axis A fixed-side liner member, a cam member that is rotatably disposed along the outer peripheral surface of the liner member and includes a plurality of cam grooves that are inclined with respect to the optical axis, and the outer periphery of each lens holding frame A lens follower that includes a cam follower that is attached to each of the parts and engages and guides each cam groove of the cam member to move each lens holding frame forward and backward in the optical axis direction when the cam member rotates. ,
Either one of the cam follower or the lens holding frame is provided with a convex portion extending in the optical axis direction, and the other is formed with a concave portion that fits into the convex portion.
The relative positional relationship in the optical axis direction between the lens holding frame and the cam follower can be adjusted by sliding the concave shape portion in the optical axis direction to fit the convex shape portion. Lens barrel to be used.

A plurality of lens holding frames that hold the lens and move in the optical axis direction, and support each lens holding frame individually so as to be able to advance and retract in the optical axis direction, and prohibit rotation of each lens holding frame around the optical axis A fixed-side liner member, a cam member that is rotatably disposed along the outer peripheral surface of the liner member and includes a plurality of cam grooves that are inclined with respect to the optical axis, and the outer periphery of each lens holding frame A lens follower that includes a cam follower that is attached to each of the parts and engages and guides each cam groove of the cam member to move each lens holding frame forward and backward in the optical axis direction when the cam member rotates. ,
The cam follower includes a cam follower main body that engages with the cam groove, and a cam follower base that supports the cam follower main body.
One end surface in the optical axis direction of either the cam follower base or the lens holding frame is provided with a concave shape portion extending in the optical axis direction, and the other is provided with a convex shape portion that fits into the concave shape portion.
The relative positional relationship of the lens holding frame and the cam follower in the optical axis direction can be adjusted by sliding the convex shape portion in the optical axis direction and fitting the concave shape portion to the concave shape portion. Lens barrel to be used.

3. The lens interval and the focus position held by each lens holding frame are adjusted by adjusting the relative positional relationship between the lens holding frame and the cam follower in the optical axis direction. The lens barrel described.

The lens barrel according to claim 1, wherein the cam follower and the lens holding frame are bonded together by bonding.

3. The lens according to claim 1, wherein the cam follower is allowed to move in the optical axis direction while being inhibited from rotating by being engaged with an optical axis direction guide slit of the liner member. 4. The lens barrel.

The said cam follower is provided with the structure which connected at least the cam follower main body engaged with the said cam groove, and the cam follower base part which supports this cam follower main body as another member. The lens barrel according to any one of 3 and 4.

7. The lens barrel according to claim 1, wherein one of the cam follower and the lens holding frame is a metal material, and the other material is a resin material.

The lens barrel according to claim 1, wherein a joint portion between the cam follower and the lens holding frame has a joint structure using elastic stress.

The lens barrel according to claim 8, wherein the joining structure using the elastic stress is based on press-fitting.

The lens barrel according to any one of claims 2 to 9, further comprising a configuration that adjusts image quality by displacing a relative positional relationship between the lens holding frame and the cam follower in a rotation direction. .

A camera comprising the lens barrel according to any one of claims 1 to 10.

An image projection apparatus comprising the lens barrel according to claim 1.

A lens holding frame with a cam follower attached to the outer periphery,
Either one of the cam follower or the lens holding frame is provided with a convex portion extending in the optical axis direction, and the other is formed with a concave portion that fits into the convex portion.
The relative positional relationship in the optical axis direction between the lens holding frame and the cam follower can be adjusted by sliding the concave shape portion in the optical axis direction to fit the convex shape portion. Lens holding frame to be used.

The lens holding frame according to claim 13, wherein a relative positional relationship between the lens holding frame and the cam follower in a rotation direction is adjustable.

A lens holding frame provided with a cam follower,
A lens holding frame, wherein a relative positional relationship between the lens holding frame and the cam follower in a rotating direction is adjustable.

The lens holding frame according to claim 15, wherein a relative positional relationship between the lens holding frame and the cam follower in the optical axis direction is adjustable.

A camera comprising the lens holding frame according to claim 13.

An optical apparatus comprising the lens holding frame according to any one of claims 13 to 16.