JP2004268166A

JP2004268166A - Tool installing structure and its manufacturing method

Info

Publication number: JP2004268166A
Application number: JP2003059088A
Authority: JP
Inventors: Kunio Ajimi; 國雄安心院
Original assignee: HOUSE BM CO Ltd
Current assignee: HOUSE BM CO Ltd
Priority date: 2003-03-05
Filing date: 2003-03-05
Publication date: 2004-09-30

Abstract

<P>PROBLEM TO BE SOLVED: To surely prevent falling-off from a drill holding member of a once installed core drill. <P>SOLUTION: An interposing cylindrical body 40 has a fixed sphere 44 for projecting a part of a peripheral surface toward the cylinder center from an inner peripheral surface, and a movable sphere 45 reciprocally movable in an installing hole 41c of the interposing cylindrical body 40, and projectable toward the cylinder center. While, the drill holding member 20 has a vertical groove 27a recessed on the peripheral surface in response to the fixed sphere 44 and the movable sphere 45, and an engaging groove 27 composed of a first peripheral groove 27b and a second peripheral groove 27c. The engaging groove 27 is formed so that the movable sphere 45 is positioned at the tail end of the second peripheral groove 27c in a state of positioning the fixed sphere 44 at the tail end of the first peripheral groove 27, and is provided with a switching cylindrical body 50 constituted so that a position can be changed between a fitting maintaining position for maintaining a fitting state of the movable sphere 45 to the second peripheral groove 27c and a movement allowing position for allowing the reciprocal movement in the radial direction of the movable sphere 45. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、工具装着部およびコア保持部材間に介設され両者を接続するために使用される工具の装着構造およびその製造方法に関するものである。
【０００２】
【従来の技術】
従来、特開平４−１０５８１１号公報に記載された図１３に示すようなドリル装着用部材１００が知られている。このドリル装着用部材１００は、センタードリル１１０を保持するためのドリル保持部材１０１と、このドリル保持部材１０１に着脱自在に装着されるコアドリル１０６とを備えた基本構成を有している。ドリル保持部材１０１は、図略の回転工具に接続される棒状のシャンク１０２と、このシャンク１０２に同心で一体に接続されたシャンク１０２より大径のドリル保持円柱１０３とからなっている。
【０００３】
ドリル保持円柱１０３は、円柱本体１０４と、この円柱本体１０４のシャンク１０２と反対側の端部に一体に形成されたコアドリル取付部（工具装着部）１０５とを備えている。コアドリル取付部１０５は、円柱本体１０４より若干小径に径設定され、これによって円柱本体１０４とコアドリル取付部１０５との間に環状段差部１０４ｂが形成されている。
【０００４】
かかるドリル保持円柱１０３には軸心に沿って同心でドリル嵌挿孔１０５ａが穿設され、センタードリル１１０がこのドリル嵌挿孔１０５ａに嵌挿された状態で円柱本体１０４の適所に径方向に延びるように螺着されたビット係止ビス１０４ａが締め付け方向に回転操作されることにより、センタードリル１１０がドリル保持円柱１０３に抜け止め状態で保持されるようになっている。
【０００５】
前記コアドリル１０６は、内径寸法が前記コアドリル取付部１０５の外径寸法より僅かに小さく径設定された小径筒体（取付部）１０７と、この小径筒体１０７の端縁から同心で延設された当該小径筒体１０７より大径の大径筒体１０８とからなっている。大径筒体１０８の下端縁部には、周方向に等ピッチで凹設された略筒心方向に延びる排出溝１０８ａが設けられているとともに、各排出溝１０８ａの入口側の角部であって、コアドリル１０６の回転方向における後方側の部分には切削刃１０８ｂが固定されている。
【０００６】
そして、小径筒体１０７の適所には、外周面から内周面に向けて例えば押し起しで形成された係合突起１０７ａが突設されている一方、前記ドリル保持円柱１０３のコアドリル取付部１０５には、その外周面に係合突起１０７ａに対応した係合溝１０５ｂが凹設され、係合突起１０７ａがこの係合溝１０５ｂに嵌り込み得るようになっている。
【０００７】
かかる係合溝１０５ｂは、コアドリル取付部１０５の筒心方向に延びる縦溝１０５ｃと、この縦溝１０５ｃの終点位置からドリル保持部材１０１の駆動回転方向と反対方向に延びる横溝１０５ｄとによってＬ字状に形成されている。そして、係合突起１０７ａを縦溝１０５ｃに沿わせつつ小径筒体１０７をコアドリル取付部１０５に嵌め込んだ後、コアドリル１０６を筒心回りに横溝１０５ｄの延びる方向へ向けて回動操作することにより、係合突起１０７ａが横溝１０５ｄの奥部に嵌り込み、これによってコアドリル１０６は軸心方向へ抜け止め状態になる。
【０００８】
また、ドリル保持部材１０１を駆動回転（ドリル装着用部材１００を下から目視した状態で反時計方向へ向かう駆動回転）させると、係合突起１０７ａがますます横溝１０５ｄの奥部へ誘導され、これによるいわゆる回り締めによってコアドリル１０６のドリル保持部材１０１に対する装着状態がより確実になり、穿孔作業中にコアドリル１０６が外れるような不都合の発生を防止することができる。
【０００９】
【特許文献１】
特開平４−１０５８１１号公報
【００１０】
【発明が解決しようとする課題】
ところで上記のような従来のドリル装着用部材１００にあっては、工具の駆動で当該ドリル装着用部材１００を回転させているときにコアドリル１０６がドリル保持部材１０１から外れることはない。しかしながら、被穿孔物に対する穿孔作業が終了した時点にコアドリル１０６を被穿孔物から引き抜くに際しては、握った工具の把手を捻ってコアドリル１０６を軸心回りに正逆回動させながら行うのが通常である。従って、コアドリル１０６を回り締め方向に回動操作したときは特に問題は生じないが、逆方向に向けて回動操作したとき、係合突起１０７ａは、横溝１０５ｄから抜け出る方向に向けて力を受け、これによって縦溝１０５ｃに位置した状態になり易い。
【００１１】
そして、係合突起１０７ａが縦溝１０５ｃに位置した状態でドリル保持部材１０１を手前に引くと、係合突起１０７ａは縦溝１０５ｃを通って当該縦溝１０５ｃから抜け出てしまい、コアドリル１０６がドリル保持部材１０１から外れてしまうという不都合が生じる。
【００１２】
このように、従来のドリル装着用部材１００にあっては、被穿孔物に対する一連の穿孔作業において、コアドリル１０６がドリル保持部材１０１から外れ易く、作業性が劣るという問題点を有していた。
【００１３】
かかる不都合を解消するために、上記従来のドリル装着用部材１００にあっては、横溝１０５ｄは、溝深さが終端に向かうに従い漸減するとともに、終端では係合突起１０７ａの先端が溝底を突っ張る程度に溝浅になるように溝底にテーパーがつけられている。こうすることによって係合突起１０７ａは、横溝１０５ｄの終端に到達することにより溝底によって押圧され、この押圧力に起因した摩擦力でコアドリル１０６は回り止めされる。
【００１４】
しかしながら、回り止めを確実にするために前記テーパーをきつくすると、前記押圧力が予想以上に大きくなってしまう場合があり、こうなるとコアドリル１０６の回動操作によるドリル保持部材１０１からの取り外しが困難になる等コアドリル１０６の工具装着部１０１に対する着脱操作の操作性が劣ることになる。
【００１５】
本発明は、上記のような問題点を解消するためになされたものであり、一旦装着された所定の工具（例えば上記のコアドリル）の工具装着部（例えば上記のコアドリル取付部）からの脱落を確実に防止することができるとともに、工具の取付部（例えば上記の小径筒体）の工具装着部からの取り外しも容易とし、これによってドリル装着用部材の作業性を大幅に向上させ得る工具の装着構造およびその製造方法を提供することを目的としている。
【００１６】
【課題を解決するための手段】
請求項１記載の発明は、円筒状の外周面を有する工具装着部に対して円筒状の取付部を有する工具を着脱可能に装着するための工具の装着構造であって、前記取付部の内周面に周方向に並ぶように凹設された複数の圧入孔に一部が突出した状態で圧入固定される第１係合部材と、取付部に貫設された径方向に延びる装着孔内で正逆移動し得るとともに、抜け止め状態で筒心に向けて突出し得る第２係合部材とが設けられている一方、前記工具装着部の周面には、第１係合部材を案内する軸心方向に延びた縦溝と、この縦溝の終端位置から工具装着部の駆動回転方向と反対方向に延びた、第１係合部材を案内する横溝と、第１係合部材が横溝の終端位置に位置した状態で第２係合部材に対応した位置に凹設された凹部とが設けられ、第２係合部材が凹部に嵌り込んだ状態を維持させる嵌込み維持位置と、第２係合部材の径方向への正逆移動を許容する移動許容位置との間で位置変更可能に構成された切替手段が設けられてなることを特徴とするものである。
【００１７】
この発明によれば、取付部を、第１係合部材が係合溝の縦溝に位置合わせされた状態で工具装着部に外嵌することにより、第１係合部材は、縦溝に案内されつつ取付部が工具装着部に嵌り込んでいく。そして、第１係合部材が縦溝の終端に到達した時点で取付部を工具装着部に対し横溝の延びる方向と反対方向に向けて軸心回りに相対回動することにより、第１係合部材が横溝に案内されつつその終端に到達し、取付部のこれ以上の回動が阻止される。
【００１８】
一方、第１係合部材が横溝の終端に到達すると、第２係合部材は、凹部に対向した状態になっている。この状態で移動許容位置に位置設定されていた切替手段を嵌込み維持位置に位置変更することにより、第２係合部材が凹部に嵌り込み、この嵌り込み状態が固定されるため、工具装着部に対する取付部の逆方向への回動が阻止される。
【００１９】
すなわち、切替手段が嵌込み維持位置に位置設定されることにより、第１係合部材が横溝の終端に位置するとともに、第２係合部材が反対側の凹部に嵌り込んだ状態になるため、取付部は軸心回りに正逆いずれの方向へも回動が阻止されることになり、これによって特に穿孔操作の終了時に取付部を有する工具を被穿孔物から引き抜くに際して当該工具が工具装着部に対し相対的に逆方向に回動する力を受けても取付部が工具装着部に対して相対的に回動することはなく、工具の被穿孔物からの引き抜き操作時に取付部が工具装着部から外れるような不都合が確実に防止される。
【００２０】
また、一旦工具装着部に装着された取付部は、切替手段を嵌込み維持位置から移動許容位置に位置変更させることにより、凹部に嵌り込んでいた第２係合部材が装着孔内を移動して当該凹部から外れ得るようになるため、取付部の軸心回りの回動操作で横溝に嵌り込んでいる第１係合部材を当該横溝に案内させつつ移動させることが可能になり、第１係合部材が縦溝に到達した時点で取付部を工具装着部から引き抜くことで工具装着部から容易に取り外すことができる。
【００２１】
請求項２記載の発明は、請求項１記載の発明において、前記第１および第２係合部材は、それぞれ第１および第２球体によって形成されていることを特徴とするものである。
【００２２】
この発明によれば、第１および第２係合部材がそれぞれ方向性のない球体（第１球体および第２球体）で形成されていることにより、取付部への各係合部材の装着操作が容易になる。
【００２３】
請求項３記載の発明は、請求項２記載の発明において、前記第２球体は、径寸法が第１球体より大径で、且つ前記取付部の厚み寸法より大きく径設定され、前記第１球体は、前記取付部に周面から径方向に穿設された貫通孔の対向内壁面にさらに穿設された有底孔に圧入され、前記装着孔は、前記貫通孔が取付部内に臨む部分を残して拡径されることによって形成されてなることを特徴とするものである。
【００２４】
この発明によれば、取付部の周面から径方向に向かうように穿設された貫通孔を介して対向内周面に形成された有底孔に第１球体を圧入するとともに、貫通孔を利用して径寸法の大きい装着孔を設け、この装着孔に第２球体を抜け止め状態で挿入するという方法で取付部へ第１球体および第２球体を容易に装着することができ、組み付けコストの低減化に貢献する。
【００２５】
請求項４記載の発明は、請求項１乃至３のいずれかに記載の発明において、前記切替手段は、前記第２係合の前記取付部内に突出した状態を拘束する部分と、この拘束を解除する部分とが取付部の筒心方向に並んで設けられてなることを特徴とするものである。
【００２６】
この発明によれば、切替手段を、取付部に対して筒心方向に移動するという簡単な操作で押出し操作部が第２球体を取付部内へ押し出すため、第２球体の押し出し操作が容易になる。
【００２７】
請求項５記載の発明は、請求項３記載の発明において、前記切替手段は、前記取付部材に外嵌される切替筒体を備えて構成され、この切替筒体は、内径寸法が取付部材の外径寸法より大きい遊嵌筒部と、この遊嵌筒部の内周面から筒心方向に向けて突設され且つ内径寸法が取付部材の外周面に摺接し得るように径設定された環状突起とを備えるとともに、前記嵌込み維持位置に位置設定された状態で環状突起が第２球体を押圧して当該第２球体を取付部材内に突出させる一方、前記移動許容位置に位置設定された状態で第２球体への押圧が解除されて前記突出が解消され得るように構成されてなることを特徴とするものである。
【００２８】
この発明によれば、切替筒体が移動許容位置に位置設定されているとき（すなわち、遊嵌筒部の内周面が装着孔内の第２球体に対向しているとき）には、第２球体は、環状突起による押圧が解除されて取付部内への強制的な突出が解消された状態になっているため、介設筒体は、第２球体に規制されることなく第１球体が係合溝に案内される範囲で工具装着部に対して移動し得るようになる。
ついで、第１球体を工具装着部の横溝に案内させるようにして介設筒体を工具装着部回りに回動操作することにより、第１球体が第一横溝の終端に到達するとともに、このとき第２球体は凹部の終端に位置した状態になる。
【００２９】
この状態で介設筒体に外嵌されている切替筒体をスライドさせて嵌込み維持位置に位置設定することにより、第２球体は、環状突起に押圧されて介設筒体内に突出し、凹部の終端に嵌り込み、かつ、この嵌り込んだ状態が固定されるため、介設筒体、延いては当該介設筒体に装着されている取付部を備えた工具は、工具装着部に対する相対回動が規制された状態になる。
【００３０】
そして、第２球体として介設筒体の装着孔内を移動し得る第２球体を採用するとともに、切替手段として環状突起を備えた切替筒体を採用することにより、工具の装着構造を簡単なものにした上で、被穿孔物からの工具の引き抜き操作時に当該工具が介設筒体を介して工具装着部から外れるような不都合を確実に防止することができる。
【００３１】
請求項６記載の発明は、請求項５記載の発明において、前記切替筒体は、取付部材に螺着されその回転操作により嵌込み維持位置と移動許容位置との間で位置変更可能に構成されてなることを特徴とするものである。
【００３２】
この発明によれば、介設筒体に対する切替筒体の筒心方向へ向かう移動は、切替筒体を介設筒体回りに回転させることによって行われる。したがって、切替筒体は、それを回転させない限り筒心方向へ移動することはなく、一旦設定された切替筒体の嵌込み維持位置や移動許容位置は確実に維持されるため、穿孔作業中に切替筒体の位置が変わり難く、穿孔作業の作業性が向上する。
【００３３】
請求項７記載の発明は、請求項３記載の工具の装着構造の製造方法であって、工具装着部の周面に前記縦溝、横溝および凹部を形成する溝・凹部形成工程と、前記取付部に第１球体および第２球体をそれぞれ装着する有底孔および装着孔を穿孔する穿孔工程と、前記有底孔に第１球体を装着するとともに、前記装着孔に第２球体を装着する球体装着工程とが備えられ、前記穿孔工程では、取付部材の周面から径方向に向かうように貫通孔を穿設し、引き続きこの貫通孔に対向した内周面に有底孔を穿設したのち前記貫通孔の径寸法を拡径するとともに当該拡径孔の取付部材内に臨む部分の拡径処理を中断することにより前記装着孔を形成し、前記球体装着工程では、第１球体を装着孔を介して前記有底孔に圧入したのち、第２球体を前記装着孔に前記第２球体を挿入することを特徴とするものである。
【００３４】
この発明によれば、１回の穿孔作業で小球である第１球体用の有底孔と、大球である第２球体用の装着孔における第２球体の抜け止め部分を形成することができ、加工コストの低減化に貢献する。
【００３５】
請求項８記載の発明は、円筒状外周面を有する工具装着部に対し、この工具装着部が嵌入可能な筒状の取付部が設けられた工具を着脱可能に装着するための工具の装着構造であって、前記取付部の内周面には、その周方向に並ぶ複数の位置に圧入孔が設けられ、各圧入孔に当該取付部の内周面から内方に一部突出する状態で係合部材が圧入固定され、当該取付部の外周面に雄螺子が形成される一方、前記工具装着部の外周面には、当該工具装着部の先端側から前記各係合部材の突出部分が軸方向に侵入可能な形状を有し、かつ、その侵入した状態で当該係合部材との当接により当該工具装着部に対する前記取付部の相対回動を規制する複数の回動規制部が周方向に並ぶ複数の位置に形成され、さらに、当該工具装着部に前記取付部外周面の雄螺子と螺合可能な雌螺子をもつ雌螺子部材が当該工具装着部に対して相対回転可能で、かつ、軸方向の相対移動が規制された状態で取り付けられ、前記各係合部材が前記回転規制部と当接した状態で前記雌螺子部材の回転を伴いながら前記取付部の雄螺子が前記工具装着部の雌螺子部材の雌螺子に螺合されることにより前記取付部が当該工具装着部に保持されるように構成されていることを特徴とするものである。
【００３６】
この発明によれば、係合部材を回動規制部に位置合わせした上で取付部を工具装着部に外嵌し、引き続き雌螺子部材の雌螺子を取付部の雄螺子に螺着して締結していくことにより、取付部は、雌螺子部材内に引き入れられていき工具装着部に嵌まり込んでいく。
【００３７】
そして、取付部が雌螺子部材内に最後まで引き入れられた状態では取付部の係合部材が工具装着部の回動規制部と干渉し、これによって取付部の工具装着部に対する相対回動が阻止される。このように、取付部を工具装着部に嵌め込んだ上で雌螺子部材を取付部に螺着締結するという簡単な装着操作によって工具を回り止め状態で工具装着部に装着することが可能になり、工具装着部に対する工具の装着操作の容易性が確保される。
【００３８】
また、係合部材は、周方向に複数設けられているとともに、回動規制部も係合部材と対応するように同数設けられているため、取付部が工具装着部に外嵌された状態で、各係合部材が対応した回動規制部に当接することにより、工具装着部と取付部との間に作用する相対回転を規制する力は周方向で略均一になり、これによって両者間の確実な回り止め効果が得られる。
【００３９】
請求項９記載の発明は、請求項８記載の発明において、前記工具装着部には、前記取付部が当該工具装着部に所定量外嵌された位置で当該取付部の先端が当接する工具装着部側当接部が設けられていることを特徴とするものである。
【００４０】
この発明によれば、取付部が工具装着部に所定量外嵌された状態で取付部の先端が工具装着部側当接部に当接して両者間のこれ以上の相対的な嵌り込みが阻止されるため、取付部の工具装着部からの突出量が一定するとともに取付状態が安定する。
【００４１】
請求項１０記載の発明は、請求項９記載の発明において、前記工具装着部側当接部は、前記工具装着部の周面から径方向の外方に向かって突設され、前記雌螺子部材は、前記取付部に螺合された状態で前記装着部側取付部に当接する雌螺子部材側当接部を有し、これらの当接部の少なくとも一方は、前記取付部内への工具装着部の挿入方向の奥側に向かうに従って縮径する向きの傾斜面とされていることを特徴とするものである。
【００４２】
この発明によれば、雌螺子部材を工具装着部に装着された取付部に螺着締結していくことにより、雌螺子部材側および工具装着部側の当止部の少なくとも一方側に形成された傾斜面が他方側を押圧し、この押圧力の筒心方向へ向かう分力によって他方側を締め付けるいわゆる楔効果が得られ、これによって雌螺子部材による取付部の保持がより確実になる。
【００４３】
請求項１１記載の発明は、請求項１０記載の発明において、前記工具装着部側当接部は、前記取付部が前記工具装着部に装着された状態で、当該取付部の先端および前記雌螺子部材側当接部の双方に当接するように構成されていることを特徴とするものである。
【００４４】
この発明によれば、取付部が工具装着部に装着された状態で、工具装着部側当接部は、取付部の先端および前記雌螺子部材側当接部の双方に当接するため、工具装着部と取付部とは、工具装着部側当接部を介してより確実に一体化し、工具装着部の回転が取付部を介してより正確に工具に伝達される。
【００４５】
請求項１２記載の発明は、請求項８乃至１０のいずれかに記載の発明において、前記回動規制部は、前記工具装着部の外周面の周方向の一部に形成された軸方向に延びる平坦面によって構成され、この平坦面と前記係合部材の突出部との当接によって当該工具装着部に対する工具の取付部の相対回転が規制されるように構成されていることを特徴とするものである。
【００４６】
この発明によれば、取付部は、工具装着部に外嵌された状態で係合部材が工具装着部の周面に形成された平坦面と干渉することにより工具装着部に対する筒心回りの回動が規制される。
【００４７】
また、工具装着部の外周面の一部に平坦化のための例えば切削加工を施すことで当該工具装着部に容易に回動規制部を形成させることができ、回動規制部形成のための加工コストの低減化に貢献する。
【００４８】
【発明の実施の形態】
図１は、本発明に係る工具の装着構造が採用されたドリル装着用部材の第１実施形態を示す一部切欠き分解斜視図であり、図２は、その組み立て斜視図である。また、図３は、図２のＡ−Ａ線断面図であり、図４は、図２のＢ−Ｂ線断面図である。
【００４９】
これらの図に示すように、第１実施形態のドリル装着用部材１０は、棒状のセンタードリル６０を支持するためのドリル保持部材（工具装着部）２０と、このドリル保持部材２０に外嵌される押圧筒体３０と、この押圧筒体３０に続いてドリル保持部材２０に外嵌された状態でコアドリル（工具）７０が着脱自在に装着される介設筒体（取付部）４０と、この介設筒体４０に外嵌される切替筒体５０とを備えた基本構成を有している。
【００５０】
前記ドリル保持部材２０は、円柱状の保持部材本体２１と、この保持部材本体２１の図１における上端面から同心で突設された当該保持部材本体２１より小径のシャンク２２と、同下端面から同心で突設された保持部材本体２１より小径で且つシャンク２２より大径の円柱体２３とを備えて構成されている。かかるドリル保持部材２０は、シャンク２２が図略の工具の駆動軸に同心で嵌挿されることにより当該工具に装着される。
【００５１】
円柱体２３は、その上部で保持部材本体２１に隣接して同心で形成されたスプリング保持部２３ａと、このスプリング保持部２３ａに下方へ向けて一体に同心で連接された介設筒体保持部２３ｂとからなっている。前記スプリング保持部２３ａには、押圧筒体３０を押圧するためのコイルスプリング２８が外嵌されるようになっている。
【００５２】
円柱体２３および保持部材本体２１には、円柱体２３の図１における下端面から同心で穿設された、センタードリル６０の基端側を摺接状態で嵌挿するためのドリル嵌挿孔２４が穿設されている。また、保持部材本体２１には、周面から径方向に向けて穿設されドリル嵌挿孔２４に連通する螺子孔２５が螺設され、この螺子孔２５にビスＢが螺着されるようになっている。従って、センタードリル６０は、円柱体２３に挿入されたのちビスＢで締結されることにより抜け止め状態でドリル保持部材２０に装着されることになる。
【００５３】
また、円柱体２３の介設筒体保持部２３ｂには、上下方向の略中間位置の周面に上下方向に延びる長孔２６が設けられている。この長孔２６は、押圧筒体３０に取り付けられた後述のピンＰを差し込むためのものであり、このピンＰの存在で押圧筒体３０は、円柱体２３回りの回動が阻止された状態で筒心方向への正逆移動が可能になっている。
【００５４】
また、介設筒体保持部２３ｂには、その周面における円柱体２３より下方位置に係合溝２７が凹設されている。図５は、係合溝２７を説明するための介設筒体保持部２３ｂの部分拡大斜視図である。この図に示すように、係合溝２７は、図５における下端部が開放状態で略軸心方向に延びる縦溝２７ａと、この縦溝２７ａの終端（図１の上端）からドリル保持部材２０の駆動回転方向と反対方向（図５の右方）へ延びる第１横溝２７ｂと、縦溝２７ａの終端から第１横溝２７ｂと反対方向へ延びる第２横溝（凹部）２７ｃとからなっている。
【００５５】
かかる係合溝２７の内の縦溝２７ａおよび第１横溝２７ｂは、介設筒体４０に装着された後述の固定球体（第１球体）４４を通過させるためのものであり、第２横溝２７ｃは、同後述の可動球体（第２球体）４５を嵌り込ませるためのものである。
【００５６】
第１横溝２７ｂは、所定長さ（固定球体４４の直径の略２倍の長さ）で若干保持部材本体２１の方向に向かうように傾斜して形成されているとともに、終端部分が若干先下がりに形成され、縦溝２７ａおよび第１横溝２７ｂに案内されて移動した固定球体４４は、この先下がりになった部分に嵌り込むことによって第１横溝２７ｂの終端部分に安定した状態で位置し得るようになっている。これに対し第２横溝２７ｃは、第１実施形態においては、可動球体４５の半径と略同一の長さで円弧状に形成され、可動球体４５が位置し得るだけになっている。
【００５７】
このように構成された係合溝２７は、第１実施形態においては、後述する固定球体４４および可動球体４５に対応するように、円柱体２３の介設筒体保持部２３ｂの周面に等ピッチ（中心角１２０°ピッチ）で３つ設けられている（図４参照）。
【００５８】
前記押圧筒体３０は、円柱体２３に外嵌された状態でコイルスプリング２８の付勢力によって介設筒体保持部２３ｂに外嵌された介設筒体４０を外方（図１では下方）に向けて押圧するものであり、保持部材本体２１側に形成された大内径部３１と、この大内径部３１に連接された小内径部３２とからなっている。
【００５９】
大内径部３１は、内径寸法が円柱体２３のスプリング保持部２３ａの外径寸法よりコイルスプリング２８の太さの２倍分より僅かに大きく寸法設定されているとともに、筒心方向の長さ寸法がスプリング保持部２３ａの同寸法より若干短く寸法設定されている。
【００６０】
これに対し、小内径部３２は、介設筒体保持部２３ｂに摺接状態で外嵌し得る内径寸法が設定されている。そして、大内径部３１および小内径部３２を合わせた筒心方向の長さ寸法（すなわち押圧筒体３０の長さ寸法）は、円柱体２３の介設筒体保持部２３ｂの略１／２に設定されている。
【００６１】
また、小内径部３２には、その外周面に環状溝３３が凹設されているとともに、この環状溝３３の溝底にピン孔３３ａが貫設されている。そして、押圧筒体３０が円柱体２３に外嵌された状態でピンＰをピン孔３３ａに圧入しその先端を介設筒体保持部２３ｂの長孔２６に挿入することにより、押圧筒体３０は、長孔２６の範囲内で正逆移動し得るようになっている。
【００６２】
前記介設筒体４０は、コアドリル７０とドリル保持部材２０との間に押圧筒体３０を介して介設されるものであり、筒体本体４１と、この筒体本体４１の下端部に形成されたフランジ部４２と、フランジ部４２の図１における下端面から同心で突設された雄螺子部４３と、筒体本体４１の内周面部分に固定された固定球体４４と、固定球体４４と対向するように筒体本体４１の肉厚部分（後述する装着孔４１ｃ内）に内装された可動球体４５とを備えて構成されている。
【００６３】
筒体本体４１は、外径寸法が保持部材本体２１の外径寸法と略同一に寸法設定されているとともに、内径寸法が円柱体２３の介設筒体保持部２３ｂの外径寸法より僅かに大きく寸法設定され、これによって介設筒体保持部２３ｂに摺接状態で外嵌し得るようになっている。かかる筒体本体４１は、筒心方向の内寸法が円柱体２３の略１／２に設定されているとともに、同外寸法が内寸法より略肉厚分だけ長尺に設定されている。
【００６４】
このような筒体本体４１の上端部には、全周に亘って凹設された環状溝４１ａが設けられ、この環状溝４１ａに切替筒体５０を抜け止めするための抜止め用Ｃリング４６が装着されるようになっている。
【００６５】
また、筒体本体４１の内周面には、固定球体４４を圧入するための圧入孔（有底孔）４１ｂが、図４に示すように、中心角１２０°ピッチで３つ設けられているとともに、各圧入孔４１ｂの対向位置には、圧入孔４１ｂより大径に設定された、可動球体４５を移動可能に装着するための装着孔４１ｃが穿設されている。かかる装着孔４１ｃの孔径（直径）寸法は、筒体本体４１の肉厚寸法より若干大きめに径設定され、これによって摺接状態で装着孔４１ｃに嵌め込まれた可動球体４５は、一部が装着孔４１ｃから外部に突出するようになっている。
【００６６】
また、かかる装着孔４１ｃの筒体本体４１内に臨む部分の孔径寸法は、他の部分のそれより若干小さめに径設定され、これによって装着孔４１ｃに嵌め込まれた可動球体４５が筒体本体４１内へ抜け出るのを阻止するようになっている。
【００６７】
第１実施形態においては、圧入孔４１ｂおよび装着孔４１ｃの穿設操作、並びに固定球体４４の圧入孔４１ｂへの圧入操作および可動球体４５の装着孔４１ｃへの装着操作は以下のように実行される。すなわち、まず筒体本体４１の周面から孔径寸法が圧入孔４１ｂのそれと等しい貫通孔を、所定のドリルを用いて穿設するとともに、この貫通孔に対向した筒体本体４１の内周面に有底孔（すなわち圧入孔４１ｂ）を穿設するのである。この圧入孔４１ｂの孔深さは、固定球体４４の直径寸法よりも若干浅めとされる。
【００６８】
引き続き、前記貫通孔を介して固定球体４４をこの圧入孔４１ｂに圧入操作することにより当該固定球体４４は周面の一部が圧入孔４１ｂから外部に飛び出した状態になる。
【００６９】
ついで、前記貫通孔の径寸法を所定のドリルで拡張することにより装着孔４１ｃを形成するとともに、当該装着孔４１ｃの筒体本体４１内に臨む部分の孔径寸法が他の部分の孔径寸法より若干小さめになる時点でドリルによる穿孔操作を中断する。これによって装着孔４１ｃの筒体本体４１内に臨む部分の孔径寸法は、可動球体４５の直径寸法より小さくなっている。そして、得られた装着孔４１ｃに可動球体４５を挿入することによって、筒体本体４１内へは抜け止め状態とされた可動球体４５からなる突起が筒体本体４１内に形成されることになる。
【００７０】
また、筒体本体４１における装着孔４１ｃおよびフランジ部４２間の外周面には、切替筒体５０を螺着するための雄螺子４１ｄの螺設された雄螺子部４１ｅが形成されている。この雄螺子部４１ｅの外径寸法は、筒体本体４１の雄螺子４１ｄが螺設されていない部分の外径寸法より螺子の山高さ分だけ径寸法が大きく設定されている。
【００７１】
前記雄螺子部４３は、コアドリル７０を装着するためのものであり、外周面にコアドリル１０の後述する螺子孔７３を外嵌螺着するための雄螺子が螺設されている。かかる雄螺子部４３には、孔径寸法が前記ドリル保持部材２０のドリル嵌挿孔２４と同一のドリル嵌挿孔４７が同心で穿設されている。
【００７２】
前記切替筒体５０は、筒体本体４１に装着された状態で孔心方向に向けて正逆移動させることにより、可動球体４５の一部を装着孔４１ｃから筒体本体４１内へ強制的に突出させたり、この強制突出状態を解除したりするものであり、図１における上端部側に形成された、内径寸法が抜止め用Ｃリング４６の外径寸法より大きい大内径部５１と、この大内径部５１の内側部分で内周面から突設された環状突起５２と、この環状突起５２を境にして大内径部５１の反対側に形成された中内径部（遊嵌筒部）５３と、この中内径部５３に隣設されて切替筒体５０の他端に至る小内径部５４とを備えている。
【００７３】
前記大内径部５１は、内径寸法が抜止め用Ｃリング４６の外径寸法より若干大きめに径設定されている。また、前記環状突起５２は、内径寸法が介設筒体４０の筒体本体４１の外径寸法より僅かに大きく径設定されているとともに、筒心方向の長さ寸法が可動球体４５の直径寸法と略同一に設定されている。また、小内径部５４は、内径寸法が介設筒体４０の雄螺子４１ｄの山高さ分だけ小径に設定され、この部分に前記雄螺子４１ｄに対応した雌螺子５４ａが螺設されている。
【００７４】
そして、環状突起５２と小内径部５４の端縁部間の外寸法は、環状溝４１ａに嵌め込まれた抜止め用Ｃリング４６とフランジ部４２との間の内寸法より可動球体４５の半径分だけ短く寸法設定されているとともに、抜止め用Ｃリング４６と装着孔４１ｃの図３における上角部との間の内寸法は、環状突起５２の図３における上下方向の厚み寸法と略同一に設定されている。
【００７５】
このように構成された切替筒体５０は、その外周面に周方向等ピッチで多数の細い縦溝（ローレット）が凹設され、このローレットによる滑り止めで切替筒体５０の回動操作が容易になるようにしている。
【００７６】
前記コアドリル７０は、平面視で円形の天板７１と、この天板７１に同心で連接された円筒状のコア体７２とからなっている。天板７１の中心位置には、介設筒体４０の雄螺子部４３に螺着される螺子孔７３が設けられ、この螺子孔７３に雄螺子部４３を螺着して締結することによりコアドリル７０が介設筒体４０に装着されるようになっている。
【００７７】
コア体７２には、その先端縁面から切り込まれることにより周方向等ピッチで形成した複数の排出溝７４が設けられている。各排出溝７４の入口側の一対の角縁部の内、コアドリル７０の駆動回転の方向と反対側の位置に切削刃７５が設けられている。従って、被穿孔物にコア体７２の先端縁部を押し当てた状態でコアドリル７０を筒心回りに駆動回転させることにより、各切削刃７５が押圧筒体３０回りに円運動をしながら被穿設物を切削するため、当該被穿孔物にコア体７２の径寸法を有する孔が穿設されることになる。
【００７８】
以下、図１〜図４を基にドリル装着用部材１０の組み付けについて説明する。ドリル装着用部材１０を組み付けるに際しては、まず、コイルスプリング２８をドリル保持部材２０のスプリング保持部２３ａに外嵌し、引き続きコイルスプリング２８を圧縮させながら押圧筒体３０をドリル保持部材２０の円柱体２３に外嵌する。ついで、ピンＰを押圧筒体３０のピン孔３３ａに圧入し、その先端をドリル保持部材２０の長孔２６に嵌挿する。
【００７９】
こうすることによって押圧筒体３０は、コイルスプリング２８の付勢力により下方へ向かうように付勢された状態でドリル保持部材２０に装着される。この状態では、円柱体２３の介設筒体保持部２３ｂが押圧筒体３０から外部に突出した状態になっている。
【００８０】
そして、介設筒体４０をドリル保持部材２０の円柱体２３に装着するに際しては、予め介設筒体４０に螺着されている切替筒体５０を、その環状突起５２が抜止め用Ｃリング４６に当接し、且つ可動球体４５が径方向の外方に向けて移動可能な移動許容位置に位置設定する。この状態で固定球体４４を縦溝２７ａに位置合わせし、コイルスプリング２８の付勢力に抗して押圧筒体３０を押圧しながら介設筒体４０をドリル保持部材２０の介設筒体保持部２３ｂに嵌め込んでいく。そして、固定球体４４が縦溝２７ａの終端に到達した時点で固定球体４４が第２横溝２７ｃ内へ移動するように介設筒体４０を回動操作し、固定球体４４が第２横溝２７ｃの終端に位置した状態で回動操作を中止する。
【００８１】
これによって介設筒体４０は、押圧筒体３０を介してコイルスプリング２８の付勢力を受け、固定球体４４が第２横溝２７ｃの終端の凹み部分に嵌り込んだ状態になる。この状態で切替筒体５０を筒体本体４１に最後まで捻じ込んでいくことで当該切替筒体５０を嵌込み維持位置に位置変更する。そして、切替筒体５０が嵌込み維持位置に位置設定された状態では、切替筒体５０の環状突起５２が装着孔４１ｃ内の可動球体４５を押圧して筒体本体４１の内周面から筒体本体４１内に突出し、ドリル保持部材２０の第２横溝２７ｃに嵌り込んだ状態になる。
【００８２】
ついで、センタードリル６０を介設筒体４０のドリル嵌挿孔４７を介してドリル保持部材２０のドリル嵌挿孔２４に差し込み、ドリル保持部材２０の螺子孔２５に螺着されているビスＢを締結するとともに、コアドリル７０の螺子孔７３を介設筒体４０の雄螺子部４３に螺着して締結することにより、図２に示すように、ドリル装着用部材１０にセンタードリル６０およびコアドリル７０が装着された状態になる。
【００８３】
図６は、本発明の作用を説明するためのドリル装着用部材１０の断面図であり、（イ）は、切替筒体５０が可動球体４５の移動を許容する移動許容位置に位置設定された状態、（ロ）は、切替筒体５０が可動球体４５の設定位置を維持する嵌込み維持位置に位置設定された状態をそれぞれ示している。なお、添え字の▲１▼は、平面視の断面図（添え字▲２▼の図のＣ−Ｃ線断面図）を示し、添え字の▲２▼は、側面視の断面図を示す。
【００８４】
また、これらの図は、いずれも介設筒体４０がドリル保持部材２０に装着された後の状態（すなわち、固定球体４４がドリル保持部材２０の第１横溝２７ｂの終端部に位置するとともに、可動球体４５が同第２横溝２７ｃに対向した状態）を示している。
【００８５】
まず、図６の（イ）に示すように、切替筒体５０が嵌込み維持位置に位置設定された状態では、切替筒体５０は、その環状突起５２が抜止め用Ｃリング４６に当接し、切替筒体５０の大内径部５１が抜止め用Ｃリング４６を抱き込んだ状態になっているとともに、中内径部５３が介設筒体４０の装着孔４１ｃと対向している。
【００８６】
そして、この状態では、中内径部５３の内周面と介設筒体４０の筒体本体４１の外周面との間に隙間が形成されているため、可動球体４５は、装着孔４１ｃ内を筒体本体４１の径方向に正逆移動し得るようになっており、前記隙間側に移動することによって、たとえ可動球体４５が第２横溝２７ｃに対向していない場合でも当該可動球体４５の筒体本体４１の外周面との干渉が回避されるようになっている。
【００８７】
ついで、図６の（ロ）に示すように、切替筒体５０を筒心回りに回転操作することにより、その小内径部５４を介設筒体４０の雄螺子部４１ｅに捻じ込んでいくと、切替筒体５０の下端縁部が介設筒体４０のフランジ部４２に当止した状態で、切替筒体５０の環状突起５２が装着孔４１ｃと対向する位置に移動し、これによる押圧で可動球体４５はドリル保持部材２０の第２横溝２７ｃに嵌り込むことになる。
【００８８】
そして、可動球体４５が第２横溝２７ｃに嵌り込むことにより、図６の（ロ）−▲２▼に示すように、介設筒体４０は、固定球体４４がすでに第１横溝２７ｂの終端に嵌り込んでいることと相俟ってドリル保持部材２０に対する筒心回りの正逆回動が阻止された状態になっている。具体的には、固定球体４４がドリル保持部材２０の第１横溝２７ｂの終端に位置することによって、介設筒体４０は、図６の（ロ）−▲２▼において筒心回りの反時計方向への回動が阻止される一方、可動球体４５が第２横溝２７ｃに嵌り込むことによって、介設筒体４０は、筒心回りの時計方向への回動が阻止されるのである。
従って、切替筒体５０が嵌込み維持位置に位置設定された状態では、図６の（ロ）に示すように、介設筒体４０は、ドリル保持部材２０に対して相対回動しないように完全にロックされているため、介設筒体４０に装着されているコアドリル７０が介設筒体４０を介してドリル保持部材２０から外れるような不都合が確実に防止される。
以上詳述したように、第１実施形態に係るドリル装着用部材１０は、先端円周部に切削刃７５を備えた円筒状のコアドリル７０を、センタードリル６０が保持される円柱状のドリル保持部材２０に同心で接続するために両者間に介設されるコアドリル７０の接続構造を備えたものである。
【００８９】
かかるドリル装着用部材１０は、ドリル保持部材２０に外嵌された状態でコアドリル７０が同心で装着される介設筒体４０を備え、この介設筒体４０は、内周面から筒心に向けて周面の一部が突出した固定球体４４と、介設筒体４０に貫設された径方向に延びる装着孔４１ｃ内で正逆移動し得るとともに、抜け止め状態で筒心に向けて突出し得る可動球体４５を有している。
【００９０】
一方、前記ドリル保持部材２０は、固定球体４４および可動球体４５に対応して周面に凹設された係合溝２７を有し、この係合溝２７は、固定球体４４が案内される軸心方向に延びた縦溝２７ａと、この縦溝２７ａの終端位置からドリル保持部材２０の回転方向と反対方向に延び且つ固定球体４４を案内する第１横溝２７ｂと、この第１横溝２７ｂと反対方向に延び且つ前記可動球体４５が案内される第２横溝２７ｃとを備えている。
【００９１】
そして、かかる係合溝２７は、固定球体４４が第１横溝２７ｂの終端に位置した状態で可動球体４５が第２横溝２７ｃの終端に位置するように形状設定されているとともに、可動球体４５が第２横溝２７ｃに嵌り込んだ状態を維持させる嵌込み維持位置と、可動球体４５の径方向への正逆移動を許容する移動許容位置との間で位置変更可能に構成された切替手段としての切替筒体５０が設けられている。
【００９２】
従って、介設筒体４０を、その固定球体４４が係合溝２７の縦溝２７ａに位置合わせされた状態でドリル保持部材２０に外嵌することにより、固定球体４４が縦溝２７ａに案内されつつ介設筒体４０がドリル保持部材２０に嵌り込んでいくことになる。そして、固定球体４４が縦溝２７ａの終端に到達した時点で介設筒体４０を第１横溝２７ｂの延びる方向と反対方向に向けて軸心回りに回動することにより、固定球体４４が第１横溝２７ｂに案内されつつその終端に到達し、介設筒体４０のドリル保持部材２０に対するこれ以上の回動が阻止される。
【００９３】
一方、固定球体４４が第１横溝２７ｂの終端に到達すると、可動球体４５は、第２横溝２７ｃの終端位置に位置した状態になっているため、この状態で移動許容位置に位置設定されていた切替手段を嵌込み維持位置に位置変更することにより、第２横溝２７ｃに嵌り込んだ可動球体４５の嵌り込み状態が維持され、これによって介設筒体４０の逆方向への回動が阻止される。
【００９４】
すなわち、切替筒体５０が嵌込み維持位置に位置設定されることにより、固定球体４４が第１横溝２７ｂの終端に位置しているとともに、可動球体４５が反対側の第２横溝２７ｃの終端に位置した状態になるため、介設筒体４０は軸心回りに正逆いずれの方向へも回動が阻止されることになる。
【００９５】
従って、介設筒体４０を介してコアドリル７０を駆動回転させて被穿孔物に穿孔操作を施したとき、および穿孔操作の終了時にコアドリル７０を被穿孔物から引き抜くに際しコアドリル７０が相対的に逆方向に回動する力を受けたときの双方で介設筒体４０がドリル保持部材２０に対して相対的に回動することはなく、これによって特にコアドリル７０の被穿孔物からの引き抜き操作時に介設筒体４０がドリル保持部材２０から外れるような不都合を確実に防止することができる。
【００９６】
また、一旦ドリル保持部材２０に装着された介設筒体４０は、切替筒体５０を嵌込み維持位置から移動許容位置に位置変更させることにより、第２横溝２７ｃに嵌り込んでいた可動球体４５が装着孔４１ｃ内を移動して当該第２横溝２７ｃから外れ得るようになるため、介設筒体４０の軸心回りの回動操作で第１横溝２７ｂに嵌り込んでいる固定球体４４を当該第１横溝２７ｂに案内させつつ移動させることが可能になり、固定球体４４が縦溝２７ａに到達した時点で介設筒体４０をドリル保持部材２０から引き抜くことでドリル保持部材２０から容易に取り外すことができる。
【００９７】
このように、切替筒体５０の切替操作で介設筒体４０の正逆回動の阻止と、回動許容とを切り替え得るようにしているため、従来のように第１横溝２７ｂの溝深さを終端に向かってきついテーパーで漸次溝浅にした場合には、一旦ドリル保持部材２０に装着された介設筒体４０が固定球体４４と溝底との間の相対的な押圧力による大きな摩擦抵抗で抜け方向に回動するのが非常に困難になり、これによって介設筒体４０の取り外しの操作性が劣悪になるような不都合が生じるが、かかる不都合を確実になくすことができる。
【００９８】
なお、本発明は、第１横溝２７ｂの溝底にテーパーをつけることを排除するものではなく、テーパーをつけてもよいが、操作性が悪くなる程きついテーパーをつけることは好ましくない。
【００９９】
そして、第２球体として介設筒体４０の装着孔４１ｃ内を移動し得る可動球体４５を採用するとともに、切替手段として環状突起を備えた切替筒体５０を採用することにより、コアドリル７０の接続構造を簡単なものにした上で、被穿孔物からのコアドリル７０の引き抜き操作時に当該コアドリル７０が介設筒体４０を介してドリル保持部材２０から外れるような不都合を確実に防止することができる。
【０１００】
また、切替筒体５０と介設筒体４０とは、筒心回りに回転可能に互いに螺着されているため、介設筒体４０に対する切替筒体５０の筒心方向に向かう移動は、切替筒体５０を介設筒体４０回りに回転させることによって容易に行うことができ、逆に切替筒体５０を回転させない限り当該切替筒体５０が筒心方向へ移動することはなく、一旦設定された切替筒体５０の嵌込み維持位置や移動許容位置を確実に保持することができ、穿孔作業中に切替筒体５０の位置が変わってしまうような不都合を確実に防止することができる。
【０１０１】
そして、固定球体４４および可動球体４５の介設筒体４０への装着については、介設筒体４０の周面から径方向に向かうように貫通孔を穿設するとともに、この貫通孔に対向した内周面に有底孔を穿設し、この有底孔に貫通孔を介して固定球体４４を圧入することにより介設筒体４０内に固定球体４４の周面の一部で突起を形成し、引き続き前記貫通孔の径寸法を所定のドリルで拡張することにより装着孔４１ｃを形成するとともに、当該装着孔４１ｃの介設筒体４０内に臨む部分の孔径寸法が装着孔４１ｃの孔径寸法より若干小さめになる時点で拡張操作を中断し、得られた装着孔４１ｃに可動球体４５を挿入することによって筒体本体４１内に突起を形成させるようにしているため、介設筒体４０への固定球体４４および可動球体４５の介設筒体４０への装着操作が容易になり、延いてはドリル装着用部材１０の製造コストの低減化に貢献することができる。
【０１０２】
図７は、本発明に係る工具の装着構造が採用されたドリル装着用部材の第２実施形態を示す一部切欠き分解斜視図であり、図８は、その組み立て斜視図である。また、図９は、図８のＤ−Ｄ線断面図であり、図１０は、図８のＥ−Ｅ線断面図である。
【０１０３】
これらの図に示すように、第２実施形態のドリル装着用部材１０′は、棒状のセンタードリル６０を支持するためのドリル保持部材（工具装着部）２００と、このドリル保持部材２００に外嵌される締結筒体（雌螺子部材）３００と、ドリル保持部材２００およびコアドリル（工具）７０間に介設される介設筒体（取付部）４００とを備えた基本構成を有している。
【０１０４】
前記ドリル保持部材２００は、円柱状の保持部材本体２０１と、この保持部材本体２０１の図７における上端面から同心で突設された当該保持部材本体２０１より小径のシャンク２０２と、同下端面から同心で突設された保持部材本体２０１より小径で且つシャンク２０２より大径の円柱体２０３と、この円柱体２０３および前記保持部材本体２０１間に介設されたフランジ（工具装着部材側当接部）２０４とを備えて構成されている。かかるドリル保持部材２００は、シャンク２０２が図略の工具の駆動軸に同心で嵌挿されることにより当該工具に装着される。
【０１０５】
円柱体２０３および保持部材本体２０１には、円柱体２０３の図７における下端面から同心で穿設された、センタードリル６０の基端側を摺接状態で嵌挿するためのドリル嵌挿孔２０５が穿設されている。また、保持部材本体２０１には、周面から径方向に向けて穿設されドリル嵌挿孔２０５に連通する螺子孔２０６が螺設され、この螺子孔２０６にビスＢが螺着されるようになっている。従って、センタードリル６０は、ドリル嵌挿孔２０５に挿入されたのちビスＢで締結されることにより抜け止め状態でドリル保持部材２００に装着されることになる。
【０１０６】
前記保持部材本体２０１には、フランジ２０４より若干上方位置に全周に亘って凹設された環状溝２０７が設けられ、この環状溝２０７に抜止め用Ｃリング２０８が装着されるようになっている。この抜止め用Ｃリング２０８は、上から保持部材本体２０１に嵌め込まれた締結筒体３００が上方へ抜け出るのを防止するためのものである。かかる抜止め用Ｃリング２０８は、環状溝２０７に装着された状態で外径寸法が前記フランジ２０４のそれと同一になるように径設定されている。
【０１０７】
また、前記円柱体２０３には、下端縁部から上端近傍にかけて周面が平坦に切削されることによって周方向に等ピッチで形成した複数の平坦面（回動規制部）２０９が設けられている。本実施形態においては、平坦面２０９は１２０°ピッチで３面設けられているが、その数については特に限定はなく、３面未満であってもよいし、３面を越えてもよい。
【０１０８】
前記締結筒体３００は、前記介設筒体４００がドリル保持部材２００の円柱体２０３に外嵌された状態で、ドリル保持部材２００を介して締結筒体３００が上から外嵌螺着されるものであり、袋ナット状に形成され、内径寸法が前記フランジ２０４より僅かに大きい筒体本体３０１と、この筒体本体３０１の上縁部に同心で形成された小内径部（雌螺子部材側当接部）３０２とからなっている。
【０１０９】
前記筒体本体３０１は、内径寸法がドリル保持部材２００のフランジ２０４の外径寸法より僅かに大きく径設定されているとともに、前記小内径部３０２は、内径寸法が前記ドリル保持部材２００の保持部材本体２０１より僅かに大きく寸法設定されている。したがって、上からドリル保持部材２００の保持部材本体２０１に外嵌することにより、小内径部３０２がフランジ２０４に当止し、これによって下方へ抜け止めされるようになっている。そして、締結筒体３００が保持部材本体２０１に外嵌された状態で、保持部材本体２０１の環状溝２０７に抜止め用Ｃリング２０８が装着され、これによって締結筒体３００は上方へも抜け止めされた状態になる。
【０１１０】
かかる締結筒体３００には、筒体本体３０１の内周面に雌螺子３０３が螺設されている。この雌螺子３０３は、ドリル保持部材２００の円柱体２０３に外嵌された介設筒体４００に螺着するためのものである。
【０１１１】
このように構成された締結筒体３００は、その外周面に周方向等ピッチで多数の細い縦溝（ローレット）が凹設され、このローレットによる滑り止めで締結筒体３００の回動操作が容易になるようにしている。
【０１１２】
前記介設筒体４００は、コアドリル７０とドリル保持部材２００との間に介設されるものであり、筒体本体４０１と、この筒体本体４０１の下端面から同心で突設された雄螺子部４０２と、筒体本体４０１の内周面部分に固定された固定球体４０３とを備えて構成されている。
【０１１３】
筒体本体４０１は、略上半分の外径寸法がドリル保持部材２００のフランジ２０４の外径寸法より若干大きめに寸法設定されているとともに、略下半分がフランジ２０４の外径寸法と同一に寸法設定されている。また、内径寸法がドリル保持部材２００の円柱体２０３の外径寸法より僅かに大きく寸法設定され、これによって円柱体２０３に摺接状態で外嵌し得るようになっている。
【０１１４】
かかる筒体本体４０１の略上半分（フランジ２０４の外径寸法より若干大径になっている部分）には、前記締結筒体３００の筒体本体３０１の雌螺子３０３が螺着され得る雄螺子４０４が螺設され、筒体本体４０１が円柱体２０３に外嵌された状態で、ドリル保持部材２００に上から外嵌された締結筒体３００を筒心回りに正逆回転することにより、介設筒体４００がフランジ２０４に対して離接するようになっている。
【０１１５】
また、筒体本体４０１の内周面には、固定球体４０３を圧入するための圧入孔（有底孔）４０５が、図１０に示すように、中心角１２０°ピッチで３つ設けられているとともに、各圧入孔４０５の対向位置には、圧入孔４０５より若干大径に設定された挿通孔４０６が穿設されている。圧入孔４０５は、固定球体４０３を圧入した状態で周面の一部が外部に突出し、且つその突出量が介設筒体４００に嵌入された円柱体２０３の平坦面２０９に摺接する量になるように深さ設定されている。
【０１１６】
そして、第２実施形態においては、圧入孔４０５および挿通孔４０６の穿設操作、並びに固定球体４０３の圧入孔４０５への圧入操作は以下のように実行される。すなわち、まず筒体本体４０１の周面から孔径寸法が圧入孔４０５のそれと等しい貫通孔を、所定のドリルを用いて穿設するとともに、この貫通孔に対向した筒体本体４０１の内周面に有底孔（すなわち圧入孔４０５）を穿設するのである。この圧入孔４０５の孔深さは、固定球体４０３の直径寸法よりも若干浅めとされる。なお、圧入孔４０５の直径は、固定球体４０３の直径より僅かに小さく径設定される。
【０１１７】
引き続き、前記貫通孔の径寸法を所定のドリルで拡張することにより挿通孔４０６を形成する。その後、この挿通孔４０６を介して固定球体４０３を前記圧入孔４０５に圧入操作することにより当該固定球体４０３は周面の一部が圧入孔４０５から外部に飛び出した状態になる。
【０１１８】
前記雄螺子部４０２は、コアドリル７０を装着するためのものであり、外周面にコアドリル７０の螺子孔７３を外嵌螺着するための雄螺子が螺設されている。かかる雄螺子部４０２には、孔径寸法が前記ドリル保持部材２００のドリル嵌挿孔２０５と同一のドリル嵌挿孔４０７が同心で穿設されている。
【０１１９】
前記コアドリル７０は、平面視で円形の天板７１と、この天板７１に同心で連接された円筒状のコア体７２とからなっている。天板７１の中心位置には、介設筒体４００の雄螺子部４０２に螺着される螺子孔７３が設けられ、この螺子孔７３に雄螺子部４０２を螺着して締結することによりコアドリル７０が介設筒体４００に固定されるようになっている。
【０１２０】
コア体７２には、その先端縁面から切り込まれることにより周方向等ピッチで形成した複数の排出溝７４が設けられている。各排出溝７４の入口側の一対の角縁部の内、コアドリル７０の駆動回転の方向と反対側の位置に切削刃７５が設けられている。従って、被穿孔物にコア体７２の先端縁部を押し当てた状態でコアドリル７０を筒心回りに駆動回転させることにより、各切削刃７５が締結筒体３００回りに円運動をしながら被穿設物を切削するため、当該被穿孔物にコア体７２の径寸法を有する孔が穿設されることになる。
【０１２１】
図１１は、本発明の作用を説明するためのドリル装着用部材１０′の図であり、（イ）は、締結筒体３００が介設筒体４００に螺着されていない状態、（ロ）は、締結筒体３００が介設筒体４００に螺着された状態をそれぞれ示している。なお、添え字の▲１▼は、平面視の断面図（添え字▲２▼の図のＦ−Ｆ線断面図）を示し、添え字の▲２▼は、側面視の断面図を示す。
【０１２２】
まず、締結筒体３００が介設筒体４００に対して非螺着状態のときに、固定球体４０３が円柱体２０３の平坦面２０９に対応するようにした上で介設筒体４００の筒体本体４０１をドリル保持部材２００の円柱体２０３に外嵌することにより、図１１の（イ）に示すように、各固定球体４０３が平坦面２０９に当接した状態になる。この状態で介設筒体４００は、固定球体４０３が平坦面２０９の当接位置の周方向の左右位置と干渉するため、ドリル保持部材２００との間で筒心回りの相対回動は規制されているが、ドリル保持部材２００に対して抜け止め処理が施されていないため、この状態で穿孔作業に供することはできない。
【０１２３】
そこで、締結筒体３００の雌螺子３０３を介設筒体４００の雄螺子４０４にねじ込んで締結する。そうすると、締結筒体３００は、小内径部３０２がフランジ２０４に当止していることにより筒心方向への移動が規制された状態になっているため、介設筒体４００が締結筒体３００内に嵌まり込んでいき、ついには、図１１の（ロ）に示すように、介設筒体４００の上縁部がドリル保持部材２００の円柱体２０３の下縁部に押圧状態で当止する。これによって介設筒体４００のドリル保持部材２００に対する接続状態が安定するため、ドリル装着用部材１０′を穿孔作業に供し得るようになる。
【０１２４】
一旦ドリル保持部材２００に連結された介設筒体４００を取り外すに際しては、締結筒体３００をドリル保持部材２００の装着時とは逆方向へ回転させればよい。こうすることによって、締結筒体３００に螺着されていた介設筒体４００は、ドリル保持部材２００の円柱体２０３から離間する方向に移動するため、これによって介設筒体４００をドリル保持部材２００から容易に取り外すことができる。
【０１２５】
以上詳述したように、第２実施形態のドリル装着用部材１０′によれば、介設筒体４００には、その内周面から一部を突出させた状態で圧入固定される固定球体４０３が設けられている一方、ドリル保持部材２００の周面には、固定球体４０３との干渉でドリル保持部材２００および介設筒体４００間の相対回動を規制する平坦面２０９を設けたため、固定球体４０３が平坦面２０９に位置合わせされた状態で介設筒体４００をドリル保持部材２００に外嵌することにより、固定球体４０３と回動記載部との干渉で介設筒体４００の筒心回りの回動を阻止することができる。このように、介設筒体４００をドリル保持部材２００に嵌め込むという簡単な装着操作によってコアドリル７０を回り止め状態でドリル保持部材２００に装着することが可能になり、ドリル保持部材２００に対する工具の装着操作の容易性を確保することができる。
【０１２６】
また、ドリル保持部材２００の平坦面２０９は、ドリル保持部材２００の周面の一部に平坦化のための例えば切削加工を施すことにより容易に得ることができ、加工コストの低減化に貢献することができる。
【０１２７】
図１２は、第２実施形態の変形形態に係るドリル装着用部材１０″を示す側面視の断面図である。図１２に示すように、変形形態のドリル装着用部材１０″は、ドリル保持部材２００に、先のフランジ２０４に代えてテーパー付きフランジ２０４′が採用されているとともに、締結筒体３００の小内径部３０２の内周面に、テーパー付きフランジ２０４′に対応した傾斜内周面３０２′が形成されている点が第２実施形態のドリル装着用部材１０′と相違している。変形形態のその他の構成は、第２実施形態のものと同様である。
【０１２８】
そして、テーパー付きフランジ２０４′は、その外径寸法が図１２における下端部から上方に向かうに従い漸減し、環状溝２０７の直下で保持部材本体２０１と同径になるように形状設定されている一方、傾斜内周面３０２′は、テーパー付きフランジ２０４′の外周面と密着し得るように形状設定されている。
【０１２９】
変形形態のドリル装着用部材１０″によれば、締結筒体３００を介設筒体４００に螺着締結した状態で、締結筒体３００の傾斜内周面３０２′がドリル保持部材２００のテーパー付きフランジ２０４′の外周面を押圧し、この押圧力の筒心方向へ向かう分力によって締結筒体３００の傾斜内周面３０２′がテーパー付きフランジ２０４′の外周面を締め付けるいわゆる楔効果が得られ、これによって締結筒体３００による介設筒体４００の保持がより確実になる。
【０１３０】
したがって、変形形態のドリル装着用部材１０″を用いた穿孔作業中に締結筒体３００が緩んで介設筒体４００がドリル保持部材２００から外れてしまうような不都合を確実に防止することができる。
【０１３１】
本発明は、上記の実施形態に限定されるものではなく、以下の内容をも包含するものである。
【０１３２】
（１）上記の第１実施形態においては、ドリル保持部材２０の介設筒体保持部２３ｂの周面に周方向に等ピッチで３つの係合溝２７が設けられているが、本発明は、係合溝２７が３つであることに限定されるものではなく、３つ未満であってもよいし、３つ以上であってもよい。因みに、係合溝２７に対応して介設筒体４０に設けられる固定球体４４および可動球体４５は、係合溝２７の設置数に合わせて同数が設けられる。
【０１３３】
（２）上記の第１実施形態においては、介設筒体４０内に突起を形成させるために可動球体４５が採用されているが、突起を形成させる部材が球体であることに限定されるものではなく、円柱体や楕円体など各種の形状のものを採用することができる。
【０１３４】
（３）上記の第１実施形態においては、ドリル保持部材２０の保持部材本体２１と、ドリル保持部材２０の介設筒体保持部２３ｂに外嵌された介設筒体４０との間に、ドリル保持部材２０の円柱体２３に外嵌された押圧筒体３０が介設されているが、本発明は、押圧筒体３０の存在を必須とするものではなく、特に押圧筒体３０を設けなくてもよい。
【０１３５】
（４）上記の第１実施形態においては、可動球体４５が嵌り込むドリル保持部材２０の介設筒体保持部２３ｂに凹設される凹部として、縦溝２７ａに連続した第２横溝２７ｃが採用されているが、本発明は、凹部が第２横溝２７ｃであることに限定されるものではなく、縦溝２７ａとは連続していない単なる凹部であってもよい。要は、固定球体４４が第１横溝２７ｂの終端に位置した状態で、凹部が可動球体４５に対向していればよいのである。
【０１３６】
【発明の効果】
本発明の請求項１記載の工具の装着構造によれば、取付部をその第１係合部が係合溝の縦溝に位置合わせされた状態で工具装着部に外嵌することにより、第１係合部が縦溝に案内されつつ取付部が工具装着部に嵌り込んでいくとともに、第１係合部が縦溝の終端に到達した時点で取付部を横溝の延びる方向と反対方向に向けて軸心回りに回動することにより、第１係合部が横溝に案内されつつその終端に到達し、これによって取付部のこれ以上の回動を阻止することができる。
【０１３７】
一方、第１係合部が横溝の終端に到達すると、第２係合部は、凹部の終端位置に位置した状態になっているため、この状態で移動許容位置に位置設定されていた切替手段を嵌込み維持位置に位置変更することにより、凹部に嵌り込んだ第２係合部の嵌り込み状態が維持され、これによって取付部の逆方向へ向かう回動を阻止することができる。
【０１３８】
すなわち、切替手段が嵌込み維持位置に位置設定されることにより、第１係合部が横溝の終端に位置しているとともに、第２係合部が反対側の凹部の終端に位置した状態になっているため、取付部は軸心回りに正逆いずれの方向へも回動が阻止されることになり、これによって取付部を介して工具を駆動回転させて被穿孔物に穿孔操作を施したとき、および穿孔操作の終了時に工具を被穿孔物から引き抜くに際し工具が相対的に逆方向に回動する力を受けたときの双方で取付部が工具装着部に対して相対的に回動することはなく、これによって特に工具の被穿孔物からの引き抜き操作時に取付部が工具装着部から外れるような不都合を確実に防止することができる。
【０１３９】
また、一旦工具装着部に装着された取付部は、切替手段を嵌込み維持位置から移動許容位置に位置変更させることにより、凹部に嵌り込んでいた第２係合部が装着孔内を移動して当該凹部から外れ得るようになるため、取付部の軸心回りの回動操作で横溝に嵌り込んでいる第１係合部を当該横溝に案内させつつ移動させることが可能になり、第１係合部が縦溝に到達した時点で取付部を工具装着部から引き抜くことで工具装着部から容易に取り外すことができる。
【０１４０】
本発明の請求項８記載の工具の装着構造によれば、取付部には、その内周面から内方に向けて一部を突出させ係合部材が設けられている一方、工具装着部の周面には、係合部材により工具装着部および取付部間の相対回動を規制する回動規制部が設けられているため、取付部を、係合部材が回動規制部に位置合わせされた状態で工具装着部に外嵌することにより、係合部材と回動記載部との干渉で取付部の回動を阻止することができる。このように、取付部を工具装着部に嵌め込むという簡単な装着操作によって工具を回り止め状態で工具装着部に装着することが可能になり、工具装着部に対する工具の装着操作の容易性を確保することができる。
【０１４１】
また、雌螺子部材を取付部に螺着することによって取付部の工具装着部に対する装着状態が安定し、作業途中で取付部が工具装着部から外れるような不都合が防止され、安全な作業を確保することができる。
【図面の簡単な説明】
【図１】本発明に係る工具の装着構造が採用されたドリル装着用部材の一実施形態を示す一部切欠き分解斜視図である。
【図２】図１に示すドリル装着用部材の組み立て斜視図である。
【図３】図２のＡ−Ａ線断面図である。
【図４】図２のＢ−Ｂ線断面図である。
【図５】係合溝を説明するための円柱体の介設筒体保持部の部分拡大斜視図である。
【図６】本発明の作用を説明するためのドリル装着用部材の断面図であり、（イ）は、切替筒体が可動球体の移動を許容する移動許容位置に位置設定された状態、（ロ）は、切替筒体が可動球体の設定位置を維持する嵌込み維持位置に位置設定された状態をそれぞれ示している。なお、添え字の▲１▼は、平面視の断面図（添え字▲２▼の図のＣ−Ｃ線断面図）を示し、添え字の▲２▼は、側面視の断面図を示す。
【図７】本発明に係る工具の装着構造が採用されたドリル装着用部材の第２実施形態を示す一部切欠き分解斜視図である。
【図８】図７に示すドリル装着用部材の組み立て斜視図である。
【図９】図８のＣ−Ｃ線断面図である。
【図１０】図８のＥ−Ｅ線断面図である。
【図１１】本発明の作用を説明するためのドリル装着用部材の図であり、（イ）は、締結筒体が介設筒体に螺着されていない状態、（ロ）は、締結筒体が介設筒体に螺着された状態をそれぞれ示している。なお、添え字の▲１▼は、平面視の断面図（添え字▲２▼の図のＦ−Ｆ線断面図）を示し、添え字の▲２▼は、側面視の断面図を示す。
【図１２】第２実施形態の変形形態に係るドリル装着用部材を示す側面視の断面図である。
【図１３】従来のドリル装着用部材を示す斜視図である。
【符号の説明】
１０，１０′，１０″ ドリル装着用部材
２０，２００ドリル保持部材（工具装着部）
２１，２０１保持部材本体２２，２０２シャンク
２３，２０３円柱体２３ａスプリング保持部
２３ｂ介設筒体保持部２４ドリル嵌挿孔
２０４フランジ（工具装着部材側当接部）
２０４′ テーパー付きフランジ
２５，２０６螺子孔２６長孔
２７係合溝２７ａ縦溝
２７ｂ第１横溝（横溝）２７ｃ第２横溝（凹部）
２０７環状溝２０８抜止め用Ｃリング
２０９平坦面（回動規制部）
２８コイルスプリング３０押圧筒体
３００締結筒体（雌螺子部材）
３０１筒体本体３０２小内径部（雌螺子部材側当接部）
３０２′ 傾斜内周面
３０３雌螺子３１大内径部
３２小内径部３３環状溝
３３ａピン孔４０，４００介設筒体（取付部）
４１，４０１筒体本体４１ａ環状溝
４１ｂ，４０５圧入孔（有底孔）
４１ｃ装着孔４１ｄ雄螺子
４１ｅ雄螺子部４２フランジ部
４３雄螺子部４４，４０３固定球体（第１球体）
４５可動球体（第２球体）４６抜止め用Ｃリング
４７ドリル嵌挿孔４０２雄螺子部
４０４雄螺子４０５圧入孔
４０６挿通孔４０７ドリル嵌挿孔
５０切替筒体５１大内径部
５２環状突起５３中内径部（遊嵌筒部）
５４小内径部５４ａ雌螺子
６０センタードリル７０コアドリル（工具）
７１天板７２コア体
７３螺子孔７４排出溝
７５切削刃[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tool mounting structure interposed between a tool mounting portion and a core holding member and used for connecting both, and a method of manufacturing the same.
[0002]
[Prior art]
Conventionally, there is known a drill mounting member 100 as shown in FIG. 13 described in Japanese Patent Application Laid-Open No. 4-105581. The drill mounting member 100 has a basic configuration including a drill holding member 101 for holding a center drill 110, and a core drill 106 detachably mounted on the drill holding member 101. The drill holding member 101 includes a rod-shaped shank 102 connected to a rotary tool (not shown), and a drill holding column 103 having a diameter larger than that of the shank 102 concentrically and integrally connected to the shank 102.
[0003]
The drill holding column 103 includes a column main body 104 and a core drill mounting portion (tool mounting portion) 105 integrally formed at an end of the column main body 104 opposite to the shank 102. The diameter of the core drill mounting portion 105 is set to be slightly smaller than the diameter of the column main body 104, whereby an annular step portion 104 b is formed between the column main body 104 and the core drill mounting portion 105.
[0004]
A drill insertion hole 105a is formed concentrically along the axis of the drill holding cylinder 103, and a center drill 110 is radially inserted into a proper position of the cylinder main body 104 with the center drill 110 inserted into the drill insertion hole 105a. The center drill 110 is held in the drill holding cylinder 103 in a retaining state by rotating the bit locking screw 104a screwed so as to extend in the tightening direction.
[0005]
The core drill 106 is concentrically extended from an end edge of the small-diameter cylindrical body (mounting part) 107 whose inner diameter is set slightly smaller than the outer diameter of the core drill mounting part 105. The large-diameter cylinder 108 has a larger diameter than the small-diameter cylinder 107. At the lower end edge of the large-diameter cylindrical body 108, there are provided discharge grooves 108a which are recessed at equal pitches in the circumferential direction and extend substantially in the center of the cylinder. The cutting blade 108b is fixed to a portion on the rear side in the rotation direction of the core drill 106.
[0006]
An engagement projection 107a formed by, for example, being pushed up from the outer peripheral surface toward the inner peripheral surface is provided at an appropriate position of the small-diameter cylindrical body 107, while the core drill mounting portion 105 of the drill holding cylinder 103 is provided. On the outer peripheral surface, an engagement groove 105b corresponding to the engagement protrusion 107a is formed in a concave shape, and the engagement protrusion 107a can be fitted into the engagement groove 105b.
[0007]
The engaging groove 105b is formed into an L-shape by a vertical groove 105c extending in the cylinder direction of the core drill mounting portion 105 and a horizontal groove 105d extending from the end point of the vertical groove 105c in the direction opposite to the driving rotation direction of the drill holding member 101. Is formed. Then, after fitting the small-diameter cylindrical body 107 into the core drill mounting portion 105 while aligning the engaging projections 107a along the vertical grooves 105c, the core drill 106 is rotated around the cylinder center in the direction in which the lateral groove 105d extends. Then, the engaging projection 107a fits into the deep portion of the lateral groove 105d, whereby the core drill 106 is prevented from coming off in the axial direction.
[0008]
Further, when the drill holding member 101 is driven to rotate (driving in the counterclockwise direction while the drill mounting member 100 is viewed from below), the engaging projections 107a are increasingly guided to the depth of the lateral grooves 105d, As a result, the state of attachment of the core drill 106 to the drill holding member 101 becomes more reliable, and it is possible to prevent the inconvenience that the core drill 106 comes off during the drilling operation.
[0009]
[Patent Document 1]
JP-A-4-105581
[0010]
[Problems to be solved by the invention]
In the conventional drill mounting member 100 described above, the core drill 106 does not come off the drill holding member 101 when the drill mounting member 100 is rotated by driving the tool. However, when the core drill 106 is pulled out of the drilled object at the time when the drilling operation on the drilled object is completed, it is usual to twist the handle of the grasped tool and rotate the core drill 106 forward and reverse around the axis. is there. Therefore, there is no particular problem when the core drill 106 is turned in the rotation tightening direction. However, when the core drill 106 is turned in the reverse direction, the engaging projection 107a receives a force in the direction of coming out of the lateral groove 105d. This tends to cause the state of being located in the vertical groove 105c.
[0011]
When the drill holding member 101 is pulled toward the user with the engagement protrusion 107a positioned in the vertical groove 105c, the engagement protrusion 107a comes out of the vertical groove 105c through the vertical groove 105c, and the core drill 106 holds the drill. There is a disadvantage that the member 101 comes off the member 101.
[0012]
As described above, the conventional drill mounting member 100 has a problem that the core drill 106 is easily detached from the drill holding member 101 in a series of drilling operations on an object to be drilled, resulting in poor workability.
[0013]
In order to solve such inconvenience, in the above-mentioned conventional drill mounting member 100, the lateral groove 105d gradually decreases as the groove depth goes to the terminal end, and at the terminal end, the tip of the engaging projection 107a sticks to the groove bottom. The groove bottom is tapered so that the groove becomes shallow. By doing so, the engagement projection 107a reaches the end of the lateral groove 105d and is pressed by the groove bottom, and the core drill 106 is prevented from rotating by the frictional force resulting from this pressing force.
[0014]
However, if the taper is tightened in order to secure the rotation, the pressing force may become larger than expected, which makes it difficult to remove the core drill 106 from the drill holding member 101 by the rotation operation. The operability of attaching / detaching the core drill 106 to / from the tool mounting portion 101 becomes inferior.
[0015]
The present invention has been made in order to solve the above-described problems, and it is intended to prevent a predetermined tool (for example, the core drill) once dropped from a tool mounting portion (for example, the core drill mounting portion) from dropping. In addition to being able to reliably prevent the mounting of the tool, the mounting of the tool (for example, the small-diameter cylindrical body described above) can be easily removed from the tool mounting portion, thereby greatly improving the workability of the drill mounting member. It is an object to provide a structure and a method of manufacturing the same.
[0016]
[Means for Solving the Problems]
The invention according to claim 1 is a tool mounting structure for removably mounting a tool having a cylindrical mounting portion to a tool mounting portion having a cylindrical outer peripheral surface. A first engaging member that is press-fitted and fixed in a state where a part thereof projects into a plurality of press-fitting holes that are concavely formed in the circumferential surface so as to be aligned in a circumferential direction, and a radially extending mounting hole that is provided through a mounting portion. And a second engaging member that can be moved forward and backward and that can protrude toward the cylinder core in a retaining state, while the first engaging member is guided on the peripheral surface of the tool mounting portion. A longitudinal groove extending in the axial direction, a lateral groove extending from the terminal position of the longitudinal groove in a direction opposite to the driving rotation direction of the tool mounting portion, for guiding the first engaging member, A concave portion provided at a position corresponding to the second engagement member in a state where the second engagement portion is located at the end position; A switching means configured to be changeable between a fitting maintaining position for maintaining a state in which the second fitting member is fitted in the concave portion and a movement allowing position for allowing forward and reverse movement of the second engaging member in the radial direction. It is characterized by being performed.
[0017]
According to this invention, the first engaging member is guided by the vertical groove by fitting the mounting portion to the tool mounting portion in a state where the first engaging member is aligned with the vertical groove of the engaging groove. The mounting part fits into the tool mounting part while being pressed. When the first engaging member reaches the end of the vertical groove, the mounting portion is relatively rotated around the axis with respect to the tool mounting portion in the direction opposite to the direction in which the horizontal groove extends, thereby providing the first engagement member. The member reaches the end while being guided by the lateral groove, and further rotation of the mounting portion is prevented.
[0018]
On the other hand, when the first engagement member reaches the end of the lateral groove, the second engagement member is in a state facing the recess. In this state, by changing the position of the switching means, which has been set at the movement allowable position, to the fitting maintaining position, the second engaging member fits into the concave portion, and the fitting state is fixed. Is prevented from rotating in the opposite direction.
[0019]
That is, since the first engagement member is located at the end of the lateral groove and the second engagement member is engaged with the concave portion on the opposite side by setting the switching means to the engagement maintaining position, The mounting portion is prevented from rotating in both the forward and reverse directions around the axis, so that when the tool having the mounting portion is pulled out of the drilled object at the end of the drilling operation, the tool is attached to the tool mounting portion. The mounting part does not rotate relative to the tool mounting part even if it receives a force that rotates relatively in the opposite direction, and the mounting part mounts the tool when the tool is pulled out from the drilled object The inconvenience of coming off from the part is reliably prevented.
[0020]
Further, the mounting portion once mounted on the tool mounting portion changes the position of the switching means from the fitting maintaining position to the movement allowable position, so that the second engaging member fitted in the concave portion moves in the mounting hole. As a result, the first engaging member fitted into the lateral groove can be moved while being guided by the lateral groove by a rotation operation about the axis of the mounting portion, and the first engaging member can be moved. When the engaging member reaches the vertical groove, the mounting portion can be easily removed from the tool mounting portion by pulling out the mounting portion from the tool mounting portion.
[0021]
According to a second aspect of the present invention, in the first aspect of the invention, the first and second engaging members are formed by first and second spheres, respectively.
[0022]
According to the present invention, since the first and second engagement members are each formed of a sphere (a first sphere and a second sphere) having no direction, the mounting operation of each engagement member to the mounting portion can be performed. It will be easier.
[0023]
According to a third aspect of the present invention, in the second aspect of the present invention, the second sphere has a larger diameter than the first sphere and a larger diameter than the thickness of the mounting portion. Is press-fitted into a bottomed hole further drilled on the opposed inner wall surface of a through hole radially drilled from the peripheral surface to the mounting portion, and the mounting hole has a portion where the through hole faces the mounting portion. It is characterized by being formed by expanding the diameter while leaving it.
[0024]
According to the present invention, the first sphere is press-fitted into the bottomed hole formed in the opposed inner peripheral surface via the through hole formed so as to extend in the radial direction from the peripheral surface of the mounting portion, and the through hole is formed. The first sphere and the second sphere can be easily mounted on the mounting portion by providing a mounting hole having a large diameter by using the mounting hole and inserting the second sphere into the mounting hole in a retaining state, and assembling cost. Contribute to the reduction of
[0025]
According to a fourth aspect of the present invention, in the first aspect of the present invention, the switching means restrains a state where the second engagement protrudes into the mounting portion, and releases the restraint. Are provided side by side in the direction of the center of the cylinder of the mounting portion.
[0026]
According to the present invention, the push-out operation section pushes the second sphere into the attachment section by a simple operation of moving the switching means in the cylindrical direction with respect to the attachment section, so that the pushing operation of the second sphere is facilitated. .
[0027]
According to a fifth aspect of the present invention, in the third aspect of the present invention, the switching means is provided with a switching cylinder fitted externally to the mounting member, and the switching cylinder has an inner diameter of the mounting member. A loose fitting tube portion larger than the outer diameter dimension, and an annular shape projecting from the inner peripheral surface of the loose fitting tube portion toward the cylinder center and having an inner diameter dimension set so as to be in sliding contact with the outer peripheral surface of the mounting member. And the annular projection presses the second sphere in a state where it is set at the fitting maintaining position to cause the second sphere to protrude into the mounting member, while being set at the movement allowable position. In this state, the pressure on the second sphere is released so that the protrusion can be eliminated.
[0028]
According to this invention, when the switching cylinder is set at the movement allowable position (that is, when the inner peripheral surface of the loose fitting cylinder faces the second sphere in the mounting hole), Since the two spheres are in a state where the pressing by the annular projection is released and the forcible projection into the mounting portion is eliminated, the interposed cylindrical body is not restricted by the second sphere, and the first sphere is not restricted by the second sphere. The tool can be moved relative to the tool mounting portion within a range guided by the engagement groove.
Then, the first spherical body reaches the end of the first lateral groove by rotating the interposition cylinder around the tool mounting part so that the first spherical body is guided in the lateral groove of the tool mounting part. The second sphere is located at the end of the recess.
[0029]
In this state, the second spherical body is pushed by the annular projection and protrudes into the intermediate cylindrical body by sliding the switching cylindrical body externally fitted to the intermediate cylindrical body to set the position at the fitting maintaining position. And the fixed state of the fitted state, the tool provided with the interposed cylindrical body and, consequently, the mounting portion mounted on the interposed cylindrical body, can be moved relative to the tool mounting portion. The rotation is restricted.
[0030]
In addition, by adopting a second sphere capable of moving in the mounting hole of the interposed cylinder as the second sphere and adopting a switching cylinder having an annular projection as the switching means, the tool mounting structure can be simplified. In addition, it is possible to reliably prevent the inconvenience of the tool being detached from the tool mounting portion via the interposed cylinder when the tool is pulled out from the object to be drilled.
[0031]
According to a sixth aspect of the present invention, in the invention of the fifth aspect, the switching cylinder is screwed to a mounting member and is configured to be changeable between a fitting maintaining position and a movement allowing position by a rotation operation thereof. It is characterized by becoming.
[0032]
According to the present invention, the movement of the switching cylinder toward the cylinder center with respect to the intermediate cylinder is performed by rotating the switching cylinder about the intermediate cylinder. Therefore, the switching cylinder does not move in the direction of the cylinder center unless the switching cylinder is rotated, and the fitting maintaining position and the movement allowable position of the switching cylinder once set are surely maintained. The position of the switching cylinder is hard to change, and the workability of the drilling operation is improved.
[0033]
According to a seventh aspect of the present invention, there is provided the method of manufacturing the tool mounting structure according to the third aspect, wherein a groove / recess forming step of forming the vertical groove, the lateral groove, and the concave on a peripheral surface of the tool mounting portion; Drilling a bottomed hole and a mounting hole for mounting a first sphere and a second sphere respectively on a portion, and mounting a first sphere in the bottomed hole and mounting a second sphere in the mounting hole An attaching step is provided. In the perforating step, a through hole is formed so as to extend in a radial direction from a peripheral surface of the mounting member, and a bottomed hole is continuously formed on an inner peripheral surface facing the through hole. The mounting hole is formed by expanding the diameter of the through-hole and interrupting the processing of expanding the portion of the diameter-enhancing hole that faces the mounting member. After press-fitting into the bottomed hole via It is characterized in that inserting the second sphere.
[0034]
According to the present invention, it is possible to form the bottomed hole for the first sphere which is a small ball and the retaining portion of the second sphere in the mounting hole for the second sphere which is a large ball by one drilling operation. And contribute to reduction of processing cost.
[0035]
The invention described in claim 8 is a tool mounting structure for removably mounting a tool provided with a cylindrical mounting portion into which the tool mounting portion can be fitted, with respect to the tool mounting portion having a cylindrical outer peripheral surface. In the inner peripheral surface of the mounting portion, press-fit holes are provided at a plurality of positions arranged in the circumferential direction, and in each of the press-fit holes, a portion protrudes inward from the inner peripheral surface of the mounting portion. The engaging member is press-fitted and fixed, and a male screw is formed on the outer peripheral surface of the mounting portion. On the outer peripheral surface of the tool mounting portion, a protruding portion of each of the engaging members from the distal end side of the tool mounting portion. A plurality of rotation restricting portions having a shape capable of invading in the axial direction, and restricting relative rotation of the mounting portion with respect to the tool mounting portion by abutting on the engaging member in the intruded state. Are formed at a plurality of positions aligned in the direction, A female screw member having a female screw that can be screwed with the child is mounted in a state where it is relatively rotatable with respect to the tool mounting portion, and the relative movement in the axial direction is restricted, and each of the engagement members is rotated. The male screw of the mounting portion is screwed into the female screw of the female screw member of the tool mounting portion while rotating the female screw member in contact with the restricting portion, so that the mounting portion is attached to the tool mounting portion. Characterized in that it is configured to be held in
[0036]
According to the present invention, after the engaging member is aligned with the rotation restricting portion, the mounting portion is externally fitted to the tool mounting portion, and then the female screw of the female screw member is screwed to the male screw of the mounting portion for fastening. By doing so, the mounting portion is pulled into the female screw member and fits into the tool mounting portion.
[0037]
When the mounting portion is completely pulled into the female screw member, the engaging member of the mounting portion interferes with the rotation restricting portion of the tool mounting portion, thereby preventing the mounting portion from rotating relative to the tool mounting portion. Is done. In this manner, the tool can be mounted on the tool mounting portion in a detented state by a simple mounting operation in which the mounting portion is fitted into the tool mounting portion and the female screw member is screwed and fastened to the mounting portion. In addition, the easiness of the operation of mounting the tool on the tool mounting portion is ensured.
[0038]
In addition, since a plurality of engaging members are provided in the circumferential direction, and the same number of rotation restricting portions are provided so as to correspond to the engaging members, the mounting portion is externally fitted to the tool mounting portion. Since each engagement member comes into contact with the corresponding rotation restricting portion, the force for restricting the relative rotation acting between the tool mounting portion and the mounting portion becomes substantially uniform in the circumferential direction. A reliable detent effect can be obtained.
[0039]
According to a ninth aspect of the present invention, in the invention of the eighth aspect, the tool mounting portion is configured such that a tip of the mounting portion abuts on the tool mounting portion at a position where the mounting portion is externally fitted to the tool mounting portion by a predetermined amount. A part-side contact part is provided.
[0040]
According to the present invention, in a state where the mounting portion is externally fitted to the tool mounting portion by a predetermined amount, the distal end of the mounting portion abuts on the tool mounting portion side contact portion to prevent further relative fitting between the two. Therefore, the amount of protrusion of the mounting portion from the tool mounting portion is constant, and the mounting state is stable.
[0041]
According to a tenth aspect of the present invention, in the invention of the ninth aspect, the tool mounting portion-side contact portion is provided to project radially outward from a peripheral surface of the tool mounting portion, and the female screw member is provided. Has a female screw member side contact portion that comes into contact with the mounting portion side mounting portion in a state of being screwed to the mounting portion, and at least one of these contact portions is a tool mounting portion inside the mounting portion. The tapered surface is characterized in that it has an inclined surface in a direction of decreasing the diameter toward the back side in the insertion direction.
[0042]
According to this invention, the female screw member is formed on at least one of the female screw member side and the abutting portion on the tool mounting portion side by screwing and fastening the female screw member to the mounting portion mounted on the tool mounting portion. The inclined surface presses the other side, and a so-called wedge effect is obtained in which the other side is tightened by a component force of the pressing force toward the cylinder center, whereby the holding of the mounting portion by the female screw member becomes more reliable.
[0043]
According to an eleventh aspect of the present invention, in the invention according to the tenth aspect, the tool mounting portion-side abutting portion includes a tip of the mounting portion and the female screw when the mounting portion is mounted on the tool mounting portion. It is characterized in that it is configured to contact both of the member-side contact portions.
[0044]
According to this invention, when the mounting portion is mounted on the tool mounting portion, the tool mounting portion-side contact portion comes into contact with both the distal end of the mounting portion and the female screw member-side contact portion. The part and the mounting part are more reliably integrated through the tool mounting part side contact part, and the rotation of the tool mounting part is more accurately transmitted to the tool through the mounting part.
[0045]
According to a twelfth aspect of the present invention, in the invention according to any one of the eighth to tenth aspects, the rotation restricting portion extends in an axial direction formed on a part of an outer peripheral surface of the tool mounting portion in a circumferential direction. A flat surface, and a relative rotation of a mounting portion of the tool with respect to the tool mounting portion is restricted by abutment of the flat surface with a protruding portion of the engaging member. It is.
[0046]
According to the present invention, when the fitting portion is externally fitted to the tool mounting portion, the engaging member interferes with the flat surface formed on the peripheral surface of the tool mounting portion, whereby the rotation around the cylinder center with respect to the tool mounting portion. Movement is regulated.
[0047]
Further, by performing, for example, a cutting process for flattening a part of the outer peripheral surface of the tool mounting portion, the rotation restricting portion can be easily formed on the tool mounting portion, and the rotation restricting portion is formed. Contribute to reduction of processing cost.
[0048]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is an exploded perspective view, partially cutaway, showing a first embodiment of a drill mounting member employing a tool mounting structure according to the present invention, and FIG. 2 is an assembled perspective view thereof. 3 is a sectional view taken along line AA of FIG. 2, and FIG. 4 is a sectional view taken along line BB of FIG.
[0049]
As shown in these drawings, the drill mounting member 10 according to the first embodiment includes a drill holding member (tool mounting portion) 20 for supporting a bar-shaped center drill 60 and an outer fitting to the drill holding member 20. A pressurized cylindrical body (attaching portion) 40 to which a core drill (tool) 70 is detachably attached in a state of being fitted to the drill holding member 20 following the pressurized cylindrical body 30; It has a basic configuration including a switching cylinder 50 externally fitted to the intermediate cylinder 40.
[0050]
The drill holding member 20 includes a cylindrical holding member main body 21, a shank 22 having a diameter smaller than that of the holding member main body 21, which protrudes concentrically from an upper end surface of the holding member main body 21 in FIG. A cylindrical member 23 having a smaller diameter than the holding member body 21 and a larger diameter than the shank 22 is provided. The drill holding member 20 is mounted on the tool by inserting the shank 22 concentrically into the drive shaft of the tool (not shown).
[0051]
The cylindrical body 23 has a spring holding part 23a formed concentrically adjacent to the holding member main body 21 at an upper part thereof, and an interposed cylindrical body holding part integrally and concentrically connected to the spring holding part 23a downward. 23b. A coil spring 28 for pressing the pressing cylinder 30 is externally fitted to the spring holding portion 23a.
[0052]
The cylindrical body 23 and the holding member main body 21 are provided with a drill fitting hole 24 that is formed concentrically from the lower end face of the cylindrical body 23 in FIG. 1 to fit the base end side of the center drill 60 in sliding contact therewith. Are drilled. Further, a screw hole 25 is formed in the holding member main body 21 and is drilled from the peripheral surface in the radial direction and communicates with the drill insertion hole 24. The screw B is screwed into the screw hole 25. Has become. Therefore, the center drill 60 is attached to the drill holding member 20 in a state where the center drill 60 is secured by the screws B after being inserted into the columnar body 23.
[0053]
Further, an elongated hole 26 extending in the up-down direction is provided on the peripheral surface at a substantially middle position in the up-down direction in the interposed cylindrical body holding portion 23b of the columnar body 23. The elongated hole 26 is for inserting a pin P, which will be described later, attached to the pressing cylinder 30, and the pressing cylinder 30 is prevented from rotating around the cylindrical body 23 due to the presence of the pin P. Enables forward and reverse movement in the cylinder center direction.
[0054]
An engagement groove 27 is formed in the intermediate cylinder holding portion 23b at a position lower than the cylindrical body 23 on the peripheral surface thereof. FIG. 5 is a partially enlarged perspective view of the interposed cylindrical body holding portion 23b for explaining the engagement groove 27. As shown in this figure, the engaging groove 27 is formed by a vertical groove 27a extending substantially in the axial direction with the lower end in FIG. 5 open, and a drill holding member 20 extending from the end (the upper end in FIG. 1) of the vertical groove 27a. And a second lateral groove (recess) 27c extending from the end of the vertical groove 27a in the opposite direction to the first lateral groove 27b.
[0055]
The vertical groove 27a and the first horizontal groove 27b of the engagement groove 27 are for allowing a fixed spherical body (first spherical body) 44, which will be described later, mounted on the interposed cylindrical body 40 to pass therethrough, and the second horizontal groove 27c. Is for fitting a movable sphere (second sphere) 45 described later.
[0056]
The first lateral groove 27b is formed to have a predetermined length (approximately twice the diameter of the fixed sphere 44) and slightly inclined toward the holding member main body 21, and the end portion thereof is slightly lowered. The fixed sphere 44, which is formed and moved by being guided by the vertical groove 27a and the first horizontal groove 27b, can be stably positioned at the terminal end portion of the first horizontal groove 27b by fitting into the downwardly tapered portion. It has become. On the other hand, in the first embodiment, the second lateral groove 27c is formed in an arc shape with a length substantially equal to the radius of the movable sphere 45, and the movable sphere 45 can only be located.
[0057]
In the first embodiment, the engagement groove 27 thus configured is formed on the peripheral surface of the interposed cylindrical body holding portion 23b of the cylindrical body 23 so as to correspond to a fixed sphere 44 and a movable sphere 45 described later. Three are provided at a pitch (center angle pitch of 120 °) (see FIG. 4).
[0058]
The pressing cylindrical body 30 is configured such that the pressurized cylindrical body 40 externally fitted to the intermediate cylindrical body holding portion 23b by the urging force of the coil spring 28 in a state of being externally fitted to the columnar body 23 (downward in FIG. 1). And has a large-diameter portion 31 formed on the holding member main body 21 side and a small-diameter portion 32 connected to the large-diameter portion 31.
[0059]
The large inner diameter portion 31 is set to have an inner diameter slightly larger than twice the thickness of the coil spring 28 than the outer diameter of the spring holding portion 23 a of the cylindrical body 23, and has a length in the cylindrical direction. Are set slightly shorter than the same dimensions of the spring holding portion 23a.
[0060]
On the other hand, the inside diameter of the small inside diameter portion 32 is set such that the small inside diameter portion 32 can be fitted to the interposed cylindrical body holding portion 23b in a sliding contact state. The combined length of the large-diameter portion 31 and the small-diameter portion 32 in the tube core direction (that is, the length of the pressing tube 30) is approximately の of the interposed tube holding portion 23 b of the column 23. Is set to
[0061]
In the small inner diameter portion 32, an annular groove 33 is recessed on the outer peripheral surface, and a pin hole 33a is formed through the groove bottom of the annular groove 33. The pin P is pressed into the pin hole 33a in a state where the pressing cylinder 30 is externally fitted to the cylindrical body 23, and the leading end thereof is inserted into the elongated hole 26 of the interposed cylinder holding part 23b. Can move forward and backward within the range of the long hole 26.
[0062]
The interposed cylindrical body 40 is interposed between the core drill 70 and the drill holding member 20 via the pressing cylindrical body 30, and is formed at a cylindrical main body 41 and a lower end portion of the cylindrical main body 41. 1, a male screw portion 43 protruding concentrically from the lower end surface of the flange portion 42 in FIG. 1, a fixed sphere 44 fixed to the inner peripheral surface portion of the cylindrical body 41, and a fixed sphere 44 And a movable sphere 45 provided inside a thick portion (in a mounting hole 41c to be described later) of the cylindrical main body 41 so as to face.
[0063]
The outer diameter of the cylindrical body 41 is set to be substantially the same as the outer diameter of the holding member main body 21, and the inner diameter is slightly smaller than the outer diameter of the interposed cylindrical holder 23 b of the cylindrical body 23. The dimensions are set to be large so that they can be externally fitted to the interposed cylindrical body holding portion 23b in a sliding contact state. The cylindrical body 41 has an inner dimension in the cylinder center direction set to approximately の of the cylindrical body 23 and an outer dimension set to be longer than the inner dimension by substantially the thickness.
[0064]
An annular groove 41a recessed over the entire circumference is provided at the upper end of such a cylindrical body 41, and a retaining C-ring 46 for preventing the switching cylinder 50 from falling out in the annular groove 41a. Is to be mounted.
[0065]
Further, three press-fit holes (bottomed holes) 41b for press-fitting the fixed spheres 44 are provided on the inner peripheral surface of the cylindrical main body 41 at a pitch of 120 ° in the central angle as shown in FIG. At the opposite position of each press-fitting hole 41b, a mounting hole 41c having a diameter larger than that of the press-fitting hole 41b and for movably mounting the movable sphere 45 is formed. The hole diameter (diameter) of the mounting hole 41c is set slightly larger than the thickness of the cylindrical body 41, whereby the movable sphere 45 fitted into the mounting hole 41c in a sliding contact state is partially mounted. It protrudes outside from the hole 41c.
[0066]
The hole diameter of the portion of the mounting hole 41c facing the inside of the cylinder body 41 is set slightly smaller than that of the other portion, so that the movable sphere 45 fitted in the mounting hole 41c can be used. It is designed to prevent it from getting inside.
[0067]
In the first embodiment, the operation of forming the press-fit hole 41b and the mounting hole 41c, the press-fitting operation of the fixed sphere 44 into the press-fit hole 41b, and the mounting operation of the movable sphere 45 into the mounting hole 41c are performed as follows. You. That is, first, a through hole having a hole diameter equal to that of the press-fitting hole 41b is drilled from the peripheral surface of the cylindrical body 41 using a predetermined drill, and the inner peripheral surface of the cylindrical body 41 facing the through hole is formed. The bottomed hole (that is, the press-fit hole 41b) is formed. The depth of the press-fit hole 41 b is slightly smaller than the diameter of the fixed sphere 44.
[0068]
Subsequently, the fixed sphere 44 is pressed into the press-fitting hole 41b through the through-hole, so that a part of the peripheral surface of the fixed sphere 44 protrudes outside from the press-fitting hole 41b.
[0069]
Then, the mounting hole 41c is formed by expanding the diameter of the through hole with a predetermined drill, and the hole diameter of the portion of the mounting hole 41c facing the inside of the cylindrical body 41 is slightly smaller than the hole diameter of the other portions. When the size becomes smaller, the drilling operation is interrupted. As a result, the hole diameter of the portion of the mounting hole 41c facing the inside of the cylindrical body 41 is smaller than the diameter of the movable sphere 45. Then, by inserting the movable sphere 45 into the obtained mounting hole 41c, a projection composed of the movable sphere 45 in a state of being prevented from falling into the cylindrical main body 41 is formed in the cylindrical main body 41. .
[0070]
A male screw part 41e in which a male screw 41d for screwing the switching cylindrical body 50 is formed on the outer peripheral surface between the mounting hole 41c and the flange part 42 in the cylindrical body 41. The outer diameter of the male screw portion 41e is set to be larger than the outer diameter of the portion of the cylindrical body 41 where the male screw 41d is not screwed by the height of the screw.
[0071]
The male screw portion 43 is for mounting a core drill 70, and a male screw for externally screwing a screw hole 73 described later of the core drill 10 is provided on the outer peripheral surface. A drill fitting hole 47 having the same hole diameter as the drill fitting hole 24 of the drill holding member 20 is formed in the male screw portion 43 concentrically.
[0072]
The switching cylinder 50 is forcibly moved in a forward / reverse direction toward the hole center in a state of being mounted on the cylinder main body 41, thereby forcing a part of the movable sphere 45 from the mounting hole 41c into the cylinder main body 41. A large-diameter portion 51 having an inner diameter larger than the outer diameter of the retaining C-ring 46 formed on the upper end portion in FIG. An annular projection 52 protruding from the inner peripheral surface at the inner portion of the large inner diameter portion 51, and a middle inner diameter portion (free-fitting cylindrical portion) 53 formed on the opposite side of the large inner diameter portion 51 from the annular projection 52. And a small inner diameter portion 54 adjacent to the middle inner diameter portion 53 and reaching the other end of the switching cylinder 50.
[0073]
The large-diameter portion 51 has an inner diameter slightly larger than the outer diameter of the retaining C-ring 46. The annular projection 52 has an inner diameter slightly larger than the outer diameter of the cylindrical body 41 of the interposed cylindrical body 40, and has a length in the cylindrical direction equal to the diameter of the movable sphere 45. Are set substantially the same. In addition, the small inner diameter portion 54 has an inner diameter set to be smaller by the height of the male screw 41d of the interposed cylindrical body 40, and a female screw 54a corresponding to the male screw 41d is screwed into this portion.
[0074]
The outer dimension between the annular projection 52 and the edge of the small inner diameter portion 54 is smaller than the inner dimension between the retaining C ring 46 fitted in the annular groove 41a and the flange 42 by the radius of the movable sphere 45. The inner dimension between the retaining C-ring 46 and the upper corner of the mounting hole 41c in FIG. 3 is substantially the same as the vertical dimension of the annular projection 52 in FIG. Is set.
[0075]
The switching cylinder 50 thus configured has a large number of narrow vertical grooves (knurls) formed in the outer peripheral surface thereof at a constant pitch in the circumferential direction. I am trying to be.
[0076]
The core drill 70 includes a top plate 71 that is circular in plan view, and a cylindrical core body 72 that is concentrically connected to the top plate 71. At the center position of the top plate 71, a screw hole 73 screwed into the male screw portion 43 of the interposed cylindrical body 40 is provided, and the male screw portion 43 is screwed into the screw hole 73 and fastened to form a core drill. 70 is attached to the intermediate cylinder 40.
[0077]
The core body 72 is provided with a plurality of discharge grooves 74 formed at equal pitches in the circumferential direction by being cut from the end edge surface. A cutting blade 75 is provided at a position on the opposite side of the driving rotation direction of the core drill 70 from a pair of corners on the inlet side of each of the discharge grooves 74. Accordingly, by rotating the core drill 70 around the center of the cylinder with the distal end edge of the core body 72 pressed against the object to be drilled, each cutting blade 75 makes a circular motion around the pressing cylinder 30 to perform the boring. In order to cut the object, a hole having the diameter of the core body 72 is formed in the object to be drilled.
[0078]
Hereinafter, assembling of the drill mounting member 10 will be described with reference to FIGS. When assembling the drill mounting member 10, first, the coil spring 28 is externally fitted to the spring holding portion 23 a of the drill holding member 20, and then, while the coil spring 28 is being compressed, the pressing cylinder 30 is connected to the cylindrical body of the drill holding member 20. 23. Next, the pin P is pressed into the pin hole 33 a of the pressing cylinder 30, and its tip is inserted into the long hole 26 of the drill holding member 20.
[0079]
Thus, the pressing cylinder 30 is mounted on the drill holding member 20 in a state where the pressing cylinder 30 is urged downward by the urging force of the coil spring 28. In this state, the interposed cylindrical body holding portion 23b of the cylindrical body 23 is in a state of protruding outside from the pressing cylindrical body 30.
[0080]
When the intermediate cylinder 40 is mounted on the cylindrical body 23 of the drill holding member 20, the switching cylinder 50 screwed in advance to the intermediate cylinder 40 is replaced with a C-ring for preventing the annular projection 52 from coming off. The movable sphere 45 is set at a movement allowable position where the movable sphere 45 can move radially outward. In this state, the fixed spherical body 44 is aligned with the vertical groove 27a, and the intermediate cylindrical body 40 is held by the intermediate cylindrical body holding portion of the drill holding member 20 while pressing the pressing cylindrical body 30 against the urging force of the coil spring 28. 23b. When the fixed spherical body 44 reaches the end of the vertical groove 27a, the interposition cylinder 40 is rotated so that the fixed spherical body 44 moves into the second horizontal groove 27c, and the fixed spherical body 44 is moved to the second horizontal groove 27c. The rotation operation is stopped in the state where the terminal is located at the end.
[0081]
As a result, the interposed cylindrical body 40 receives the urging force of the coil spring 28 via the pressing cylindrical body 30, and the fixed spherical body 44 is fitted in the concave portion at the end of the second lateral groove 27c. In this state, the switching cylinder 50 is screwed into the cylinder main body 41 to the end to change the position of the switching cylinder 50 to the fitting maintaining position. Then, in a state where the switching cylinder 50 is set at the fitting maintaining position, the annular projection 52 of the switching cylinder 50 presses the movable sphere 45 in the mounting hole 41 c to move the cylinder from the inner peripheral surface of the cylinder main body 41. It protrudes into the body 41 and is fitted into the second lateral groove 27c of the drill holding member 20.
[0082]
Next, the center drill 60 is inserted into the drill insertion hole 24 of the drill holding member 20 through the drill insertion hole 47 of the interposed cylinder 40, and the screw B screwed into the screw hole 25 of the drill holding member 20 is removed. As shown in FIG. 2, the center drill 60 and the core drill 70 are attached to the drill mounting member 10 by fastening the screw holes 73 of the core drill 70 to the male screw portions 43 of the interposed cylindrical body 40. Is attached.
[0083]
FIG. 6 is a cross-sectional view of the drill mounting member 10 for explaining the operation of the present invention. FIG. 6A is a view in which the switching cylinder 50 is set at a movement allowable position where the movable sphere 45 is allowed to move. The state (b) shows the state in which the switching cylinder 50 is set at the fitting maintaining position for maintaining the set position of the movable sphere 45, respectively. The suffix (1) indicates a cross-sectional view in plan view (a cross-sectional view taken along line CC in the figure of the suffix (2)), and the suffix (2) indicates a cross-sectional view in a side view.
[0084]
In each of these figures, the state after the interposed cylindrical body 40 is mounted on the drill holding member 20 (that is, the fixed spherical body 44 is located at the end of the first lateral groove 27b of the drill holding member 20 and The movable ball 45 faces the second lateral groove 27c).
[0085]
First, as shown in FIG. 6A, in a state where the switching cylinder 50 is set at the fitting maintaining position, the switching cylinder 50 has its annular projection 52 abutting against the retaining C-ring 46. The large-diameter portion 51 of the switching cylinder 50 is in a state of holding the retaining C-ring 46, and the middle-diameter portion 53 faces the mounting hole 41 c of the interposed cylinder 40.
[0086]
In this state, since a gap is formed between the inner peripheral surface of the middle inner diameter portion 53 and the outer peripheral surface of the cylindrical main body 41 of the interposed cylindrical body 40, the movable sphere 45 moves inside the mounting hole 41c. The movable spherical body 45 can move forward and backward in the radial direction of the cylindrical body 41, and by moving to the gap side, even if the movable spherical body 45 is not opposed to the second lateral groove 27c, the cylinder of the movable spherical body 45 can be moved. Interference with the outer peripheral surface of the body main body 41 is avoided.
[0087]
Next, as shown in (b) of FIG. 6, by rotating the switching cylinder 50 around the center of the cylinder, the small inner diameter portion 54 is screwed into the male screw portion 41 e of the interposed cylinder 40. With the lower end edge of the switching cylinder 50 abutting on the flange 42 of the interposed cylinder 40, the annular projection 52 of the switching cylinder 50 moves to a position facing the mounting hole 41c, and is pressed by this. The movable sphere 45 fits into the second lateral groove 27c of the drill holding member 20.
[0088]
When the movable sphere 45 is fitted into the second lateral groove 27c, as shown in (b)-(2) of FIG. 6, the interposed cylindrical body 40 has the fixed sphere 44 already at the end of the first lateral groove 27b. The forward and reverse rotation about the cylinder center with respect to the drill holding member 20 is prevented in combination with the fitting. Specifically, since the fixed spherical body 44 is located at the end of the first lateral groove 27b of the drill holding member 20, the interposed cylindrical body 40 becomes counterclockwise around the cylindrical center in (b)-(2) of FIG. While the rotation in the direction is prevented, the movable spherical body 45 is fitted into the second lateral groove 27c, so that the interposed cylinder 40 is prevented from rotating clockwise around the center of the cylinder.
Accordingly, in a state where the switching cylinder 50 is set at the fitting maintaining position, as shown in FIG. 6B, the interposed cylinder 40 is not rotated relative to the drill holding member 20. Since the core drill 70 is completely locked, the inconvenience of the core drill 70 attached to the interposed cylinder 40 coming off the drill holding member 20 via the interposed cylinder 40 is reliably prevented.
As described in detail above, the drill mounting member 10 according to the first embodiment includes a cylindrical core drill 70 provided with a cutting blade 75 at the distal end circumference, and a cylindrical drill holding the center drill 60. It is provided with a connection structure of a core drill 70 interposed between the members 20 for concentric connection with the member 20.
[0089]
The drill mounting member 10 includes an interposed cylindrical body 40 to which the core drill 70 is concentrically mounted in a state where the core drill 70 is externally fitted to the drill holding member 20, and the interposed cylindrical body 40 is moved from the inner peripheral surface to the cylindrical core. A part of the peripheral surface protrudes toward the fixed spherical body 44 and a mounting hole 41c extending in the radial direction penetrating through the interposed cylindrical body 40. It has a movable sphere 45 that can protrude.
[0090]
On the other hand, the drill holding member 20 has an engaging groove 27 formed in the peripheral surface corresponding to the fixed sphere 44 and the movable sphere 45. A longitudinal groove 27a extending in the center direction, a first lateral groove 27b extending from the terminal position of the longitudinal groove 27a in a direction opposite to the rotation direction of the drill holding member 20 and guiding the fixed sphere 44, and a first lateral groove 27b opposite to the first lateral groove 27b. And a second lateral groove 27c extending in the direction and guiding the movable sphere 45.
[0091]
The shape of the engagement groove 27 is set such that the movable sphere 45 is located at the end of the second lateral groove 27c while the fixed sphere 44 is located at the end of the first lateral groove 27b. Switching means configured to be changeable between a fitting maintaining position for maintaining a state of being fitted into the second lateral groove 27c and a movement allowing position for allowing forward and reverse movement of the movable sphere 45 in the radial direction. A switching cylinder 50 is provided.
[0092]
Therefore, the fixed spherical body 44 is guided by the vertical groove 27a by fitting the interposed cylindrical body 40 to the drill holding member 20 in a state where the fixed spherical body 44 is aligned with the vertical groove 27a of the engagement groove 27. The interposed cylindrical body 40 is fitted into the drill holding member 20 while being inserted. When the fixed spherical body 44 reaches the end of the vertical groove 27a, the intermediate cylindrical body 40 is rotated around the axis in a direction opposite to the direction in which the first horizontal groove 27b extends, so that the fixed spherical body 44 While reaching the end while being guided by the one lateral groove 27b, further rotation of the interposed cylindrical body 40 with respect to the drill holding member 20 is prevented.
[0093]
On the other hand, when the fixed sphere 44 reaches the end of the first lateral groove 27b, the movable sphere 45 is in the state of being located at the end position of the second lateral groove 27c. By changing the position of the switching means to the fitting maintaining position, the fitted state of the movable sphere 45 fitted in the second lateral groove 27c is maintained, and thereby the rotation of the interposed cylindrical body 40 in the reverse direction is prevented. You.
[0094]
That is, by setting the switching cylinder 50 at the fitting maintaining position, the fixed sphere 44 is located at the end of the first lateral groove 27b, and the movable sphere 45 is located at the end of the opposite second lateral groove 27c. Since it is located, the interposed cylindrical body 40 is prevented from rotating in both the forward and reverse directions around the axis.
[0095]
Therefore, when the core drill 70 is driven and rotated through the interposed cylindrical body 40 to perform the drilling operation on the object to be drilled, and when the core drill 70 is pulled out from the object to be drilled at the end of the drilling operation, the core drill 70 is relatively inverted. The interposed cylindrical body 40 does not rotate relative to the drill holding member 20 both when receiving the force to rotate in the direction, so that the core drill 70 particularly when the core drill 70 is pulled out from the drilled object. Inconvenience such that the interposed cylindrical body 40 comes off the drill holding member 20 can be reliably prevented.
[0096]
Further, the intermediate cylindrical body 40 once mounted on the drill holding member 20 changes the position of the switching cylindrical body 50 from the fitting maintaining position to the movement allowable position, so that the movable spherical body 45 fitted into the second lateral groove 27c. Can move in the mounting hole 41c and become disengaged from the second lateral groove 27c. Therefore, the fixed spherical body 44 fitted in the first lateral groove 27b by the rotation operation about the axis of the interposed cylindrical body 40 is removed. It becomes possible to move while being guided by the first horizontal groove 27b, and when the fixed spherical body 44 reaches the vertical groove 27a, the intermediate cylinder 40 is pulled out from the drill holding member 20 to be easily removed from the drill holding member 20. be able to.
[0097]
As described above, the switching operation of the switching cylinder 50 can switch between the forward and reverse rotation of the interposed cylinder 40 and the permissible rotation, so that the groove depth of the first lateral groove 27b is different from the related art. When the groove is gradually tapered toward the terminal end, the interposed cylindrical body 40 once mounted on the drill holding member 20 becomes large due to the relative pressing force between the fixed spherical body 44 and the groove bottom. It becomes very difficult to rotate in the pull-out direction due to frictional resistance, which causes a disadvantage that the operability of removing the interposed cylindrical body 40 deteriorates. However, such a disadvantage can be surely eliminated.
[0098]
The present invention does not exclude the provision of a taper at the bottom of the first lateral groove 27b. The taper may be provided, but it is not preferable to provide a taper that is too operable.
[0099]
The connection of the core drill 70 is achieved by employing the movable sphere 45 that can move in the mounting hole 41c of the interposed cylinder 40 as the second sphere and employing the switching cylinder 50 having the annular projection as the switching means. After simplifying the structure, it is possible to reliably prevent the inconvenience that the core drill 70 comes off the drill holding member 20 via the interposed cylindrical body 40 when the core drill 70 is pulled out from the object to be drilled. .
[0100]
Further, since the switching cylinder 50 and the intermediate cylinder 40 are screwed to each other so as to be rotatable around the cylinder center, the movement of the switching cylinder 50 toward the cylinder center with respect to the intermediate cylinder 40 is switched. This can be easily performed by rotating the cylindrical body 50 around the interposed cylindrical body 40. Conversely, unless the switching cylindrical body 50 is rotated, the switching cylindrical body 50 does not move in the direction of the cylindrical center, and is set once. Thus, it is possible to reliably hold the fitted maintenance position and the movement allowable position of the switching cylinder 50, and it is possible to reliably prevent the inconvenience of changing the position of the switching cylinder 50 during the drilling operation.
[0101]
For mounting the fixed sphere 44 and the movable sphere 45 on the interposed cylindrical body 40, a through hole is formed so as to extend radially from the peripheral surface of the interposed cylindrical body 40, and the through hole is opposed to the through hole. By forming a bottomed hole in the inner peripheral surface and press-fitting the fixed sphere 44 into the bottomed hole through a through hole, a projection is formed in the interposed cylinder 40 at a part of the peripheral surface of the fixed sphere 44 The mounting hole 41c is formed by successively expanding the diameter of the through hole with a predetermined drill, and the hole diameter of the portion of the mounting hole 41c facing the interposed cylindrical body 40 is the hole diameter of the mounting hole 41c. When the expansion operation is interrupted at a slightly smaller point and the movable sphere 45 is inserted into the obtained mounting hole 41c to form a projection in the cylindrical main body 41, the intermediate cylindrical body 40 Of the fixed sphere 44 and the movable sphere 45 Mounting operation on 設筒 body 40 is facilitated, and by extension can contribute to a reduction of manufacturing cost of the drill mounting member 10.
[0102]
FIG. 7 is a partially cut-away exploded perspective view showing a second embodiment of a drill mounting member employing a tool mounting structure according to the present invention, and FIG. 8 is an assembled perspective view thereof. FIG. 9 is a sectional view taken along line DD of FIG. 8, and FIG. 10 is a sectional view taken along line EE of FIG.
[0103]
As shown in these drawings, a drill mounting member 10 ′ of the second embodiment includes a drill holding member (tool mounting portion) 200 for supporting a rod-shaped center drill 60, and an outer fitting to the drill holding member 200. It has a basic configuration including a fastening cylinder (female screw member) 300 to be provided and an interposed cylinder (attachment) 400 interposed between the drill holding member 200 and the core drill (tool) 70.
[0104]
The drill holding member 200 has a cylindrical holding member main body 201, a shank 202 having a smaller diameter than the holding member main body 201 protruding concentrically from an upper end surface of the holding member main body 201 in FIG. A cylindrical member 203 having a diameter smaller than that of the holding member main body 201 protruding concentrically and having a diameter larger than that of the shank 202, and a flange interposed between the cylindrical member 203 and the holding member main body 201 (a contact portion on the tool mounting member side). ) 204. The drill holding member 200 is mounted on the tool by inserting the shank 202 concentrically on the drive shaft of the tool (not shown).
[0105]
The cylindrical body 203 and the holding member main body 201 are concentrically drilled from the lower end surface in FIG. 7 of the cylindrical body 203 and have a drill fitting hole 205 for fitting the base end side of the center drill 60 in sliding contact therewith. Are drilled. Further, a screw hole 206 drilled from the peripheral surface in the radial direction and communicating with the drill insertion hole 205 is screwed into the holding member main body 201, and the screw B is screwed into the screw hole 206. Has become. Therefore, the center drill 60 is inserted into the drill insertion hole 205 and then fastened with the screw B, so that the center drill 60 is attached to the drill holding member 200 in a state in which it is prevented from falling off.
[0106]
The holding member main body 201 is provided with an annular groove 207 that is recessed over the entire circumference at a position slightly above the flange 204, and a retaining C-ring 208 is attached to the annular groove 207. I have. The retaining C-ring 208 is for preventing the fastening cylinder 300 fitted into the holding member main body 201 from coming out from above. The diameter of the retaining C-ring 208 is set so that the outer diameter of the retaining C-ring 208 is the same as that of the flange 204 when mounted in the annular groove 207.
[0107]
The cylindrical body 203 is provided with a plurality of flat surfaces (rotation restricting portions) 209 which are formed at equal pitches in the circumferential direction by cutting the circumferential surface flat from the lower edge to the vicinity of the upper edge. . In the present embodiment, three flat surfaces 209 are provided at a pitch of 120 °, but the number is not particularly limited and may be less than three or more than three.
[0108]
The fastening cylinder 300 is externally screwed onto the fastening cylinder 300 from above through the drill holding member 200 in a state where the interposed cylinder 400 is externally fitted to the cylindrical body 203 of the drill holding member 200. A cylindrical body 301 formed in a cap nut shape and having an inner diameter slightly larger than the flange 204; and a small inner diameter section (female screw member side) formed concentrically with the upper edge of the cylindrical body 301. (Contact portion) 302.
[0109]
The inner diameter of the cylindrical body 301 is set slightly larger than the outer diameter of the flange 204 of the drill holding member 200, and the small inner diameter portion 302 has an inner diameter of the holding member of the drill holding member 200. The dimensions are set slightly larger than the main body 201. Therefore, the small inner diameter portion 302 abuts against the flange 204 by being externally fitted to the holding member main body 201 of the drill holding member 200 from above, and is thereby prevented from falling down. Then, in a state where the fastening cylinder 300 is externally fitted to the holding member main body 201, a retaining C-ring 208 is attached to the annular groove 207 of the holding member main body 201, whereby the fastening cylinder 300 is also prevented from coming off. It is in the state that was done.
[0110]
In the fastening cylinder 300, a female screw 303 is screwed on the inner peripheral surface of the cylinder main body 301. The female screw 303 is for screwing to the interposed cylinder 400 externally fitted to the cylindrical body 203 of the drill holding member 200.
[0111]
The fastening cylinder 300 thus configured is provided with a large number of narrow vertical grooves (knurls) in the outer peripheral surface thereof at an equal pitch in the circumferential direction, and the turning operation of the fastening cylinder 300 is facilitated by the slip prevention by the knurl. I am trying to be.
[0112]
The interposed cylinder 400 is interposed between the core drill 70 and the drill holding member 200, and includes a cylinder body 401 and a male screw concentrically projecting from a lower end surface of the cylinder body 401. It comprises a portion 402 and a fixed sphere 403 fixed to the inner peripheral surface of the cylindrical body 401.
[0113]
The outer diameter of the upper half of the cylindrical body 401 is set slightly larger than the outer diameter of the flange 204 of the drill holding member 200, and the lower half of the cylindrical body 401 has the same size as the outer diameter of the flange 204. Is set. Further, the inner diameter is set slightly larger than the outer diameter of the cylindrical body 203 of the drill holding member 200, so that the outer diameter can be fitted to the cylindrical body 203 in a sliding contact state.
[0114]
A male screw to which the female screw 303 of the cylindrical body 301 of the fastening cylindrical body 300 can be screwed is attached to a substantially upper half of the cylindrical body 401 (a part slightly larger in diameter than the outer diameter of the flange 204). 404 is screwed, and the fastening cylinder 300 externally fitted to the drill holding member 200 is rotated forward and reverse around the cylinder center in a state where the cylinder main body 401 is externally fitted to the cylindrical body 203, so that the intermediate body is rotated. The installation cylinder 400 comes into contact with and separates from the flange 204.
[0115]
In addition, three press-fit holes (bottomed holes) 405 for press-fitting the fixed sphere 403 are provided on the inner peripheral surface of the cylindrical body 401 at a pitch of 120 ° central angle as shown in FIG. At the same time, an insertion hole 406 having a diameter slightly larger than that of the press-fit hole 405 is formed at a position facing each press-fit hole 405. In the press-fit hole 405, a part of the peripheral surface protrudes outside in a state where the fixed sphere 403 is press-fitted, and the amount of protrusion is an amount that slides on the flat surface 209 of the cylindrical body 203 fitted in the interposed cylinder 400. The depth is set as follows.
[0116]
Then, in the second embodiment, the operation of piercing the press-fit hole 405 and the insertion hole 406 and the press-fit operation of the fixed sphere 403 into the press-fit hole 405 are executed as follows. That is, first, a through hole having a hole diameter equal to that of the press-fitting hole 405 is drilled from a peripheral surface of the cylindrical body 401 using a predetermined drill, and the inner peripheral surface of the cylindrical body 401 facing the through hole is formed. The bottomed hole (that is, the press-fit hole 405) is formed. The depth of the press-fit hole 405 is slightly smaller than the diameter of the fixed sphere 403. The diameter of the press-fit hole 405 is set slightly smaller than the diameter of the fixed sphere 403.
[0117]
Subsequently, the insertion hole 406 is formed by expanding the diameter of the through hole with a predetermined drill. Thereafter, the fixed sphere 403 is pressed into the press-fitting hole 405 through the insertion hole 406, so that a part of the peripheral surface of the fixed sphere 403 projects outside from the press-fitting hole 405.
[0118]
The male screw portion 402 is for mounting the core drill 70, and has a male screw for externally screwing the screw hole 73 of the core drill 70 on the outer peripheral surface. A drill fitting hole 407 having the same hole diameter as the drill fitting hole 205 of the drill holding member 200 is formed in the male screw part 402 concentrically.
[0119]
The core drill 70 includes a top plate 71 that is circular in plan view, and a cylindrical core body 72 that is concentrically connected to the top plate 71. At the center position of the top plate 71, a screw hole 73 to be screwed to the male screw portion 402 of the interposed cylindrical body 400 is provided, and the male screw portion 402 is screwed to the screw hole 73 and fastened to form a core drill. 70 is fixed to the intermediate cylinder 400.
[0120]
The core body 72 is provided with a plurality of discharge grooves 74 formed at equal pitches in the circumferential direction by being cut from the end edge surface. A cutting blade 75 is provided at a position on the opposite side of the driving rotation direction of the core drill 70 from a pair of corners on the inlet side of each of the discharge grooves 74. Accordingly, the core drill 70 is driven and rotated around the center of the cylinder while the distal end portion of the core body 72 is pressed against the object to be drilled, so that each of the cutting blades 75 performs a circular motion around the fastening cylinder 300 while being drilled. In order to cut the object, a hole having the diameter of the core body 72 is formed in the object to be drilled.
[0121]
FIG. 11 is a diagram of a drill mounting member 10 ′ for explaining the operation of the present invention. FIG. 11A shows a state in which the fastening cylinder 300 is not screwed to the interposed cylinder 400, and FIG. Indicates a state in which the fastening cylinder 300 is screwed to the interposition cylinder 400, respectively. The suffix (1) indicates a cross-sectional view in a plan view (a cross-sectional view taken along line FF of the suffix (2)), and the suffix (2) indicates a cross-sectional view in a side view.
[0122]
First, when the fastening cylinder 300 is not screwed to the interposition cylinder 400, the fixed sphere 403 corresponds to the flat surface 209 of the cylindrical body 203, and then the cylinder of the interposition cylinder 400. By externally fitting the main body 401 to the cylindrical body 203 of the drill holding member 200, each fixed sphere 403 comes into contact with the flat surface 209 as shown in FIG. In this state, since the fixed spherical body 403 interferes with the left and right circumferential positions of the abutting position of the flat surface 209 in this state, the relative rotation of the intermediate cylindrical body 400 with the drill holding member 200 around the cylindrical center is restricted. However, since the retaining process is not performed on the drill holding member 200, the drill holding member 200 cannot be used for drilling work in this state.
[0123]
Therefore, the female screw 303 of the fastening cylinder 300 is screwed into the male screw 404 of the interposed cylinder 400 and fastened. Then, since the fastening cylinder 300 is in a state where the movement in the cylinder center direction is restricted by the small inner diameter portion 302 abutting on the flange 204, the intermediate cylinder 400 is connected to the fastening cylinder 300. As shown in FIG. 11B, the upper edge of the interposed cylinder 400 is finally pressed against the lower edge of the cylindrical body 203 of the drill holding member 200 as shown in FIG. I do. As a result, the connection state of the interposed cylinder 400 to the drill holding member 200 is stabilized, so that the drill mounting member 10 'can be used for drilling.
[0124]
To remove the intermediate cylinder 400 once connected to the drill holding member 200, the fastening cylinder 300 may be rotated in a direction opposite to the direction in which the drill holding member 200 is mounted. By doing so, the intermediate cylinder 400 screwed to the fastening cylinder 300 moves in a direction away from the columnar body 203 of the drill holding member 200, and thereby the intermediate cylinder 400 is moved to the drill holding member. 200 can be easily removed.
[0125]
As described in detail above, according to the drill mounting member 10 ′ of the second embodiment, the fixed sphere 403 that is press-fitted and fixed to the interposition cylinder 400 with a part thereof protruding from the inner peripheral surface thereof. On the other hand, a flat surface 209 for restricting relative rotation between the drill holding member 200 and the interposed cylinder 400 due to interference with the fixed sphere 403 is provided on the peripheral surface of the drill holding member 200, By externally fitting the intermediate cylinder 400 to the drill holding member 200 with the sphere 403 aligned with the flat surface 209, the cylindrical core of the intermediate cylinder 400 interferes with the fixed sphere 403 and the rotation description portion. Around rotation can be prevented. As described above, the core drill 70 can be mounted on the drill holding member 200 in a detented state by a simple mounting operation of fitting the interposed cylindrical body 400 to the drill holding member 200, and Ease of mounting operation can be ensured.
[0126]
In addition, the flat surface 209 of the drill holding member 200 can be easily obtained by, for example, performing a cutting process for flattening a part of the peripheral surface of the drill holding member 200, which contributes to a reduction in processing cost. be able to.
[0127]
FIG. 12 is a cross-sectional side view showing a drill mounting member 10 ″ according to a modification of the second embodiment. As shown in FIG. 12, the drill mounting member 10 ″ according to the modification includes a drill holding member. A tapered flange 204 ′ is used in place of the flange 204, and an inclined inner peripheral surface 302 corresponding to the tapered flange 204 ′ is provided on the inner peripheral surface of the small inner diameter portion 302 of the fastening cylinder 300. Is different from the drill mounting member 10 'of the second embodiment. Other configurations of the modified embodiment are the same as those of the second embodiment.
[0128]
The tapered flange 204 ′ is configured so that its outer diameter gradually decreases upward from the lower end in FIG. 12 and has the same diameter as the holding member main body 201 immediately below the annular groove 207. , The inclined inner peripheral surface 302 ′ is shaped so as to be in close contact with the outer peripheral surface of the tapered flange 204 ′.
[0129]
According to the drill mounting member 10 ″ of the modified embodiment, the inclined inner peripheral surface 302 ′ of the fastening cylinder 300 has a taper of the drill holding member 200 when the fastening cylinder 300 is screwed and fastened to the interposition cylinder 400. A so-called wedge effect is obtained in which the outer peripheral surface of the flange 204 ′ is pressed, and the inclined inner peripheral surface 302 ′ of the fastening cylinder 300 tightens the outer peripheral surface of the tapered flange 204 ′ by a component force of the pressing force toward the cylinder center. Thus, the holding of the interposed cylinder 400 by the fastening cylinder 300 becomes more reliable.
[0130]
Therefore, it is possible to reliably prevent the inconvenience that the fastening cylinder 300 is loosened and the interposed cylinder 400 is detached from the drill holding member 200 during the drilling operation using the modified drill mounting member 10 ″. .
[0131]
The present invention is not limited to the above embodiments, but also includes the following contents.
[0132]
(1) In the above-described first embodiment, three engaging grooves 27 are provided at a constant pitch in the circumferential direction on the peripheral surface of the interposed cylindrical body holding portion 23b of the drill holding member 20. The number of the engagement grooves 27 is not limited to three, but may be less than three or three or more. Incidentally, the same number of the fixed spheres 44 and the movable spheres 45 provided on the interposed cylindrical body 40 corresponding to the engagement grooves 27 are provided in accordance with the number of the installation of the engagement grooves 27.
[0133]
(2) In the above-described first embodiment, the movable sphere 45 is employed to form a projection in the interposed cylindrical body 40, but the member for forming the projection is limited to a sphere. Instead, those having various shapes such as a cylindrical body and an elliptical body can be adopted.
[0134]
(3) In the first embodiment described above, between the holding member main body 21 of the drill holding member 20 and the interposed cylinder 40 externally fitted to the interposed cylinder holding portion 23b of the drill holding member 20. Although the pressing cylinder 30 externally fitted to the cylindrical body 23 of the drill holding member 20 is interposed, the present invention does not necessarily require the presence of the pressing cylinder 30, and in particular, the pressing cylinder 30 is provided. It is not necessary.
[0135]
(4) In the above-described first embodiment, the second horizontal groove 27c continuous with the vertical groove 27a is employed as the concave portion provided in the intermediate cylindrical body holding portion 23b of the drill holding member 20 into which the movable sphere 45 is fitted. However, the present invention is not limited to the concave portion being the second horizontal groove 27c, and may be a simple concave portion that is not continuous with the vertical groove 27a. In short, it is only necessary that the concave portion faces the movable sphere 45 in a state where the fixed sphere 44 is located at the end of the first lateral groove 27b.
[0136]
【The invention's effect】
According to the tool mounting structure of the first aspect of the present invention, the mounting portion is externally fitted to the tool mounting portion in a state where the first engagement portion is aligned with the vertical groove of the engagement groove. The mounting portion is fitted into the tool mounting portion while the first engaging portion is guided by the vertical groove, and the mounting portion is moved in the direction opposite to the direction in which the horizontal groove extends when the first engaging portion reaches the end of the vertical groove. By rotating about the axis toward the first engaging portion, the first engaging portion reaches the end thereof while being guided by the lateral groove, whereby further rotation of the mounting portion can be prevented.
[0137]
On the other hand, when the first engagement portion reaches the end of the lateral groove, the second engagement portion is located at the end position of the concave portion. By changing the position of the second engagement portion to the engagement maintaining position, the engagement state of the second engagement portion fitted in the concave portion is maintained, and thereby the rotation of the attachment portion in the opposite direction can be prevented.
[0138]
That is, by setting the switching means at the fitting maintaining position, the first engagement portion is located at the end of the lateral groove, and the second engagement portion is located at the end of the opposite concave portion. As a result, the mounting portion is prevented from rotating in both the forward and reverse directions around the axis, whereby the tool is driven and rotated through the mounting portion to perform a boring operation on the object to be drilled. The mounting part rotates relatively to the tool mounting part both when the tool is subjected to the force to rotate the tool in the opposite direction when the tool is pulled out of the object to be drilled at the end of the drilling operation. Therefore, it is possible to reliably prevent the inconvenience such that the mounting portion is detached from the tool mounting portion particularly when the tool is pulled out from the object to be drilled.
[0139]
Further, the mounting portion once mounted on the tool mounting portion changes the position of the switching means from the fitting maintaining position to the movement allowable position, so that the second engaging portion fitted in the concave portion moves in the mounting hole. As a result, the first engaging portion fitted in the lateral groove can be moved while being guided by the lateral groove by a rotating operation about the axis of the mounting portion. By pulling out the mounting portion from the tool mounting portion when the engagement portion reaches the vertical groove, the mounting portion can be easily removed from the tool mounting portion.
[0140]
According to the tool mounting structure according to claim 8 of the present invention, the mounting portion is provided with an engaging member that partially protrudes inward from the inner peripheral surface thereof, and the tool mounting portion of the tool mounting portion is provided. On the peripheral surface, a rotation restricting portion for restricting relative rotation between the tool mounting portion and the mounting portion by the engaging member is provided, so that the mounting portion is aligned with the rotation restricting portion. By externally fitting to the tool mounting portion in the folded state, the rotation of the mounting portion can be prevented by the interference between the engagement member and the rotation description portion. In this way, the simple mounting operation of fitting the mounting part into the tool mounting part makes it possible to mount the tool on the tool mounting part in a detented state, ensuring the ease of the tool mounting operation on the tool mounting part can do.
[0141]
Further, by screwing the female screw member to the mounting portion, the mounting state of the mounting portion to the tool mounting portion is stabilized, and the inconvenience of the mounting portion being detached from the tool mounting portion during the work is prevented, and a safe operation is secured. can do.
[Brief description of the drawings]
FIG. 1 is a partially cutaway exploded perspective view showing an embodiment of a drill mounting member employing a tool mounting structure according to the present invention.
FIG. 2 is an assembled perspective view of the drill mounting member shown in FIG. 1;
FIG. 3 is a sectional view taken along line AA of FIG. 2;
FIG. 4 is a sectional view taken along line BB of FIG. 2;
FIG. 5 is a partially enlarged perspective view of an interposed cylindrical body holding portion of a cylindrical body for explaining an engagement groove.
FIG. 6 is a cross-sectional view of a drill mounting member for explaining the operation of the present invention, in which (a) shows a state in which the switching cylinder is set at a movement allowable position allowing movement of the movable sphere, (B) shows the state in which the switching cylinder is set at the fitting maintaining position for maintaining the set position of the movable sphere. The suffix (1) indicates a cross-sectional view in plan view (a cross-sectional view taken along line CC in the figure of the suffix (2)), and the suffix (2) indicates a cross-sectional view in a side view.
FIG. 7 is an exploded perspective view showing a second embodiment of a drill mounting member employing a tool mounting structure according to the present invention;
FIG. 8 is an assembled perspective view of the drill mounting member shown in FIG. 7;
FIG. 9 is a sectional view taken along the line CC of FIG. 8;
FIG. 10 is a sectional view taken along line EE of FIG. 8;
FIGS. 11A and 11B are diagrams of a drill mounting member for explaining the operation of the present invention, wherein FIG. 11A shows a state in which a fastening cylinder is not screwed to an interposed cylinder, and FIG. Each of the figures shows a state where the body is screwed to the interposed cylindrical body. The suffix (1) indicates a cross-sectional view in a plan view (a cross-sectional view taken along line FF of the suffix (2)), and the suffix (2) indicates a cross-sectional view in a side view.
FIG. 12 is a side sectional view showing a drill mounting member according to a modification of the second embodiment.
FIG. 13 is a perspective view showing a conventional drill mounting member.
[Explanation of symbols]
10,10 ', 10 "Drill mounting member
20,200 Drill holding member (tool mounting part)
21,201 Holding member body 22,202 Shank
23,203 Cylindrical body 23a Spring holding part
23b Interposed cylindrical body holding part 24 Drill fitting insertion hole
204 flange (contact part on the tool mounting member side)
204 'tapered flange
25,206 Screw hole 26 Slot
27 Engagement groove 27a Vertical groove
27b First lateral groove (lateral groove) 27c Second lateral groove (recess)
207 Circular groove 208 C-ring for retaining
209 Flat surface (rotation restricting part)
28 coil spring 30 pressing cylinder
300 fastening cylinder (female screw member)
301 cylindrical body 302 small inner diameter part (contact part on female screw member side)
302 'inner slope
303 female screw 31 large bore
32 Small inner diameter part 33 Annular groove
33a Pin hole 40,400 Interposed cylinder (mounting part)
41, 401 cylindrical body 41a annular groove
41b, 405 Press-fit hole (hole with bottom)
41c Mounting hole 41d Male screw
41e Male screw part 42 Flange part
43 Male screw part 44,403 Fixed sphere (first sphere)
45 Movable sphere (second sphere) 46 C-ring for retaining
47 Drill insertion hole 402 Male thread
404 Male screw 405 Press-fit hole
406 insertion hole 407 drill insertion hole
50 Switching cylinder 51 Large inner diameter
52 Annular projection 53 Medium inner diameter part (free-fitting cylinder part)
54 Small inner diameter part 54a Female screw
60 center drill 70 core drill (tool)
71 Top plate 72 Core body
73 Screw hole 74 Discharge groove
75 Cutting Blade

Claims

A tool mounting structure for detachably mounting a tool having a cylindrical mounting portion to a tool mounting portion having a cylindrical outer peripheral surface,
A first engagement member that is press-fitted and fixed in a state where a part thereof projects into a plurality of press-fit holes that are concavely arranged in the circumferential direction on the inner peripheral surface of the mounting portion; And a second engagement member that can move forward and backward within the mounting hole extending to the main body and that can protrude toward the cylinder core in a retaining state.
On the peripheral surface of the tool mounting portion, a longitudinal groove extending in the axial direction for guiding the first engagement member, and a second groove extending from a terminal position of the longitudinal groove in a direction opposite to a driving rotation direction of the tool mounting portion. A lateral groove for guiding the first engaging member, and a concave portion provided at a position corresponding to the second engaging member in a state where the first engaging member is located at an end position of the lateral groove;
The position can be changed between a fitting maintaining position for maintaining a state in which the second engaging member is fitted in the concave portion and a movement allowing position for allowing the forward and reverse movement of the second engaging member in the radial direction. A tool mounting structure provided with switching means.

The tool mounting structure according to claim 1, wherein the first and second engagement members are formed by first and second spheres, respectively.

The second sphere has a larger diameter than the first sphere and a larger diameter than the thickness of the mounting portion, and the first sphere is formed in the mounting portion in a radial direction from a peripheral surface. The mounting hole is press-fitted into a bottomed hole further drilled on the opposed inner wall surface of the through hole, and the mounting hole is formed by expanding the diameter of the through hole leaving a portion facing the inside of the mounting portion. The mounting structure of the tool according to claim 2.

The switching means is characterized in that a portion for restraining the state of the second engagement projecting into the mounting portion and a portion for releasing the restraint are provided side by side in the cylinder direction of the mounting portion. A tool mounting structure according to any one of claims 1 to 3.

The switching means is provided with a switching cylinder externally fitted to the mounting member. The switching cylinder has an inner diameter dimension larger than the outer diameter dimension of the mounting member, and a loose fitting cylinder portion. And an annular projection whose inner diameter dimension is set so as to be able to slide on the outer peripheral surface of the mounting member from the inner peripheral surface of the mounting member. In the state, the annular projection presses the second sphere to project the second sphere into the mounting member, while the state in which the second sphere is set at the movement allowable position is released, and the protrusion is released. The tool mounting structure according to claim 3, wherein the tool mounting structure is configured to be able to be performed.

6. The tool mounting structure according to claim 5, wherein the switching cylinder is screwed to a mounting member and is configured to be changeable between a fitting maintaining position and a movement allowable position by a rotation operation thereof. .

4. The method for manufacturing a tool mounting structure according to claim 3, wherein: a groove / recess forming step of forming the vertical groove, the lateral groove, and the concave on the peripheral surface of the tool mounting part; and a first spherical body and a second spherical body on the mounting part. A piercing step of piercing a bottomed hole and a mounting hole for mounting a sphere, respectively, and a sphere mounting step of mounting a second sphere in the mounting hole while mounting a first sphere in the bottomed hole, In the drilling step, a through hole is drilled from the peripheral surface of the mounting member in the radial direction, a bottomed hole is continuously drilled on the inner peripheral surface facing the through hole, and then the diameter of the through hole is enlarged. The mounting hole is formed by interrupting the diameter expansion processing of a portion facing the inside of the mounting member of the enlarged diameter hole, and in the sphere mounting step, the first sphere is connected to the bottomed hole via the mounting hole. After press-fitting, insert the second sphere into the mounting hole Method of manufacturing a mounting structure of the tool, characterized in Rukoto.

A tool mounting structure for detachably mounting a tool provided with a cylindrical mounting portion into which the tool mounting portion can be fitted, with respect to a tool mounting portion having a cylindrical outer peripheral surface,
On the inner peripheral surface of the mounting portion, press-fit holes are provided at a plurality of positions arranged in the circumferential direction, and an engagement member is provided in each of the press-fit holes in a state of partially projecting inward from the inner peripheral surface of the mounting portion. Press-fit and fixed, while a male screw is formed on the outer peripheral surface of the mounting portion,
On the outer peripheral surface of the tool mounting portion, the projecting portion of each of the engaging members has a shape capable of intruding in the axial direction from the distal end side of the tool mounting portion, and, in the intruded state, with the engaging member. A plurality of rotation restricting portions that regulate the relative rotation of the mounting portion with respect to the tool mounting portion by the contact of the tool mounting portion are formed at a plurality of positions arranged in the circumferential direction. A female screw member having a female screw that can be screwed with a male screw is attached in a state in which it is relatively rotatable with respect to the tool mounting portion, and the relative movement in the axial direction is regulated,
The male screw of the mounting portion is screwed to the female screw of the female screw member of the tool mounting portion while the engagement member is in contact with the rotation restricting portion while the female screw member rotates. A tool mounting structure, wherein the mounting portion is configured to be held by the tool mounting portion.

The tool mounting part is provided with a tool mounting part side contact part with which the tip of the mounting part comes into contact at a position where the mounting part is fitted outside the tool mounting part by a predetermined amount. Item 9. A tool mounting structure according to Item 8.

The tool mounting portion side contact portion is provided so as to protrude radially outward from a peripheral surface of the tool mounting portion, and the female screw member is screwed to the mounting portion in the mounting portion side. A female screw member-side abutting portion that abuts the mounting portion, and at least one of the abutting portions has an inclined surface in a direction in which a diameter is reduced toward an inner side in a direction in which the tool mounting portion is inserted into the mounting portion. The tool mounting structure according to claim 9, wherein:

The tool mounting portion-side contact portion is configured to contact both the distal end of the mounting portion and the female screw member-side contact portion in a state where the mounting portion is mounted on the tool mounting portion. The tool mounting structure according to claim 10, wherein:

The rotation restricting portion is constituted by an axially extending flat surface formed on a part of the outer peripheral surface of the tool mounting portion in a circumferential direction, and is formed by abutment between the flat surface and the protrusion of the engaging member. The tool mounting structure according to any one of claims 8 to 10, wherein relative rotation of the tool mounting portion with respect to the tool mounting portion is restricted.