【０００１】
【発明の属する技術分野】
本発明はてんぷ構造体及びこれを備えた機械式時計に係る。
【０００２】
【従来の技術】
機械式時計において、アンクルと協働するてんぷによりガンギ車の歩進的回転の速度を調整ないし規定することは知られている。
【０００３】
てんぷ（本体）は、リング状乃至環状のリム部を備えたてん輪と該てん輪のアーム部を介しててん輪を支え回転中心軸となるてん真とを有し、ハウジングに装着された軸受によりてん真の両端の細い軸部で往復回動自在に支持される。てん真に固定されたひげ玉に内周端部で固定されひげ持に外周端部で固定されたひげぜんまいのバネ力及びてん輪の振り石と干渉し合うアンクルの作用下で、てん輪が往復回動される。
【０００４】
【発明が解決しようとする課題】
このような機械式時計が誤って床や地上に落とされたり該機械式時計に不測の外力が加えられたりした場合、てんぷに慣性モーメントを与えるべく質量の大きいてん輪のリム部に比較的大きな慣性力が衝撃として加えられることになり、この慣性力がてん真にかかるので、てん真がその両端の細い軸部で折れるなどてんぷが損傷を受ける虞れがあった。
【０００５】
なお、偏心錘の揺動により、ゼンマイや発電機を駆動する偏心錘付時計において、偏心錘に加えられる比較的小さな衝撃による偏心錘の軸方向の振動を急速に減衰させるために、偏心錘に近接したところに制振用の弾性材を設けることは、提案されている（特許文献１）。
【０００６】
【特許文献１】
特開２００２―３１１１６１号公報（第６〜９頁、第１図）
【０００７】
しかしながら、特許文献の提案における弾性材の利用は、偏心錘の振動の減衰を目的とするものである。なお、特許文献１においては、大きな衝撃に伴う偏心錘の位置ズレは、摩擦制動の如き他の手段によって規制しようとしている。
【０００８】
本発明は、前記諸点に鑑みなされたものであって、その目的とするところは、大きな衝撃を受けても動作不能になるような損傷を受ける虞れが少ないてんぷ構造体及びこれを備えた機械式時計を提供することにある。
【０００９】
【課題を解決するための手段】
本発明のてんぷ構造体は、前記目的を達成すべく、てん輪及び該てん輪に固定されたてん真を含むてんぷ本体と、てん真を往復回動自在に支持する軸受を支えてんぷ本体を囲繞するハウジングと、ハウジングのうちてん輪のリム部に対面する部分に装着され、てん輪のリム部の所定位置からの位置ズレを規制する緩衝材とを有する。
【００１０】
本発明のてんぷ構造体では、「てん真を往復回動自在に支持する軸受を支えてんぷ本体を囲繞するハウジングと、ハウジングのうちてん輪のリム部に対面する部分に装着され、てん輪のリム部の所定位置からの位置ズレを規制する緩衝材」が設けられているので、衝撃によるてん輪のリム部の所定位置からの位置ズレが緩衝材によって規制され得、該てん輪に固定されたてん真が所定位置からずれるのが禁止され得る。従って、てん真の細い軸部とその軸受との間に過度な力がかかる虞れが少なく、てん真の細い軸部等が衝撃により折れるなどの動作不能な損傷を受ける虞れが少ない。
【００１１】
ここで、ハウジングの本体は、てんぷ本体を往復回動可能に支え得るものであればどのような部材でもよく、典型的には、地板や中枠や外枠の如く機械式時計の外枠に対して不動な部材からなる。また、ハウジングに関して、てんぷ本体を「囲繞」とは、てん輪のリム部に対面する所定位置で緩衝材を支え得る程度にてんぷ本体の周囲にあることをいい、てんぷ本体を囲ってしまうことを要しない。
【００１２】
緩衝材は、てん輪に加わる衝撃力を十分に弱め得る限りどのような材料や構造でもよいけれども、典型的には、ゴムや軟質合成樹脂等の材料で形成される。
【００１３】
緩衝材は、ハウジングに対して不動に該ハウジングに静置ないし固定されていてもよいけれども、典型的には、ハウジングに対して位置調整可能に該ハウジングに装着されている。この場合、てん輪のリム部と緩衝材との間隙の大きさを（必要な範囲で）最低限に調整し得るのでてんぷ構造体が衝撃によって損傷を受ける虞れを最小限に低減することが可能になる。
【００１４】
緩衝材は、てん輪のリム部が通常の往復回動の際に採る位置からの所定の大きさを超えるどのようなズレを規制するようになっていてもよいけれども、典型的には、
（１）ハウジングのうちてん輪のリム部の環状端面に対向する部位、及び
（２）ハウジングのうちてん輪のリム部の外周面に対向する部位
のうちの少なくともいずれか一方の部分に装着される。
【００１５】
前者すなわち（１）の場合、てんぷ構造体の軸方向に沿う方向へのてん輪の移動やてん輪の延在面が両側の軸受を結ぶ方向に対して垂直な向きからずれるようなてんぷの傾きすなわちてん輪のリム部や傾きや変形を抑制し得る。
【００１６】
一方、後者すなわち（２）の場合、てん輪のリム部が両側の軸受を結ぶ位置から径方向にずれ、てんぷ構造体の中心軸をなすてん真が両側の軸受を結ぶ位置から径方向にずれるのを抑制し得る。
【００１７】
緩衝材は、例えば、環状や円形や円筒状などであってもよいけれども、典型的には、てん輪のリム部の周方向に沿って間隔を置いて複数個装着されている。これにより、緩衝材の形状や寸法精度がそれほど高くなくても、個々に配置したり位置決めすることが可能になる。また、緩衝材の位置調整が行われる場合には、その位置調整が容易に行われやすい。
【００１８】
緩衝材は、てん輪のリム部の位置ズレを規制し得る限りどのような形状を有していてもよく、典型的には、緩衝材のうちてん輪のリム部に対面する表面部分が実質的に平面であるけれども、その代わりに、てん輪の対向表面部分に向かって先細になっていてもよい。この場合、緩衝材の断面形状が台形又はかまぼこ型である。ここで、かまぼこ型とは、典型的には、半円形であるけれども、湾局面の曲率は一定でなくてもよい。
【００１９】
なお、緩衝材は、その断面形状がＬ字型であってもよく、その場合、Ｌの一方の脚部がてん輪のリム部の外周面に対向し、他方の脚部がてん輪のリム部の環状端面に対向するように配置される。
【００２０】
本発明の機械式時計では、以上のようなてんぷ構造体を備えることにより、衝撃に対して、てん輪構造体が損傷を受ける虞れが最低限に抑えられ得る。
【００２１】
【発明の実施の形態】
本発明の好ましい実施の形態のいくつかを添付図面に示した好ましい実施例に基づいて説明する。
【００２２】
【実施例】
図１の（ａ）及び（ｂ）には、第一実施例のてんぷ構造体１を含む調速機構２を備えた機械式時計３が示されている。
【００２３】
時計３は、外枠（図示せず）に対して静置された地板４や中枠や輪列の受部（支持部）の如きハウジング部分５，６（以下では、便宜上、中枠と呼ぶけれども地板４の一部でも、輪列受やてんぷ受等の如き他の静置部材であってもよい）を含む。この例では、ハウジングは、地板４及び中枠５，６からなる。
【００２４】
地板４と中枠５との間には、てんぷ構造体１の本体即ちてんぷ本体としてのてんぷ２０が、中心軸線ＣのまわりでＣ１，Ｃ２方向に回転可能に配設されている。
【００２５】
てんぷ２０は、中枠５及び地板４に中心軸線Ｃに沿って形成された上及び下の軸受１０ａ，１０ｂ（てんぷ上軸受とてんぷ下軸受とを区別しないとき又は総称するときには符号「１０」で表す）により両端の細い軸部２１，２２において該中心軸線Ｃのまわりで回転自在に支持されたてん真２３と、てん輪本体をなす環状のリム部２４及び該リム部２４に両端でつながり該リム部２４の直径方向に延びたアーム部２５を備え該アーム部２５の中間部２６においててん真２３の中央軸部２７に固定されたてん輪２８と、てん真２３の上側軸部２９に取付けられたひげ玉３０と、内周端部３１でひげ玉３０に取付けられ外周端部３２でひげ持３３に取付けられたひげぜんまい乃至ひげ３５と、大小のつば部ないしフランジ部３６，３７を備えると共に大フランジ部３６で振り石３８を保持してん真２３の下側軸部３９に取付けられた振り座４０とを有する。
【００２６】
てんぷ上軸受１０ａは、内側及び外側軸受枠１１ａ，１２ａを含む上側の組合せ軸受枠１３ａと、該軸受枠１３ａの中径凹部に配設されてん真２３の上端の小径軸部２２のジャーナル軸受として働くてんぷ上穴石１４ａと、軸受枠１３ａの大径凹部に配設されてん真２３の上端小径軸部２２のスラスト軸受として働くてんぷ上受石１５ａと、軸受枠１３ａの溝に係止され受石１５ａを軸受枠１３ａ内に保持する受石押さえバネ１６ａとを有する。てんぷ下軸受１０ｂは、内側及び外側軸受枠１１ｂ，１２ｂを含む下側の組合せ軸受枠１３ｂと、該軸受枠１３ｂの中径凹部に配設されてん真２３の下端小径軸部２１のジャーナル軸受として働くてんぷ下穴石１４ｂと、軸受枠１３ｂの大径凹部に配設されてん真２３の下端小径軸部２１のスラスト軸受として働くてんぷ下受石１５ｂと、軸受枠１３ｂの溝に係止され受石１５ｂを軸受枠１３ｂ内に保持する受石押さえバネ１６ｂとを有する。上下の軸受１０ａ，１０ｂは同様に構成されているので、両者を区別しないとき又は総称するときには、その部材についても、符号「ａ」や「ｂ」を省いて、符号１１，１２，１３，１４，１５，１６等で示す。但し、軸受１０ａ，１０ｂがてん真２３を中心軸線Ｃのまわりで往復回動自在に支持し得る限り、上下の振り座１０ａ，１０ｂの構造が相互に異なっていてもよい。
【００２７】
なお、ひげ持３３は、中枠５に対して中心軸線Ｃのまわりで位置調整可能なひげ持受４１に取付けねじ４２で固定されている。てんぷ上軸受１０ａのところには、更に、緩急針支持アーム４３が中心軸線ＣのまわりでＣ１，Ｃ２方向に回転可能に取付けられている。緩急針支持アーム４３は、ひげぜんまい３５の外周側の大径部分４４に当接する緩急針４５を先端部に担持し、緩急針支持アーム４３をＣ１，Ｃ２方向に回動させて緩急針４５がひげぜんまい３５の大径部分４４に当接するＣ１，Ｃ２方向の位置ないし部位を調整することにより、ひげぜんまい３５の実効長及びバネ定数が変化せしめられて、てん輪２８のＣ１，Ｃ２方向の往復回転（往復回動）の周期が調整され得る。
【００２８】
てんぷ２０の振り石３８には、アンクル真５１のまわりでＤ１，Ｄ２方向に往復回動可能なアンクル５０の三本のアーム部５２，５３，５４のうちフォーク状のアーム部の形態のアンクルさお５２が係合可能である。アンクル５０の残りの二本のアーム部５３，５４のうちの一方のアーム５３が入りづめ５５を他方のアーム５４が出づめ５６を備え、振り石３８によりＤ１，Ｄ２方向に回動されるアンクル５０の入りづめ５５及び出づめ５６が中心軸線ＱのまわりでＱ１方向に回転されるガンギ車５７のガンギ歯５８に交互に係合されることにより、香箱（図示せず）によってＱ１回転駆動されるガンギ車５７の歩進的回転を許容する。
【００２９】
てんぷ構造体１は、更に、地板４に装着された第一の軸線方向緩衝機構６０及び周方向緩衝機構７０と、中枠５に装着された第二の軸線方向緩衝機構８０とを有する。各緩衝機構６０，７０，８０は、図１に示した例では、中心軸線Ｃのまわりで周方向にほぼ等間隔に三個形成されている。なお、他の時計部品の配置の関係で配設スペースの制約がある場合には、図１の（ａ）に示したように、正確に等間隔でなくてもよい。周方向に形成された三個の緩衝機構６０，７０，８０は、該緩衝機構６０，７０，８０の夫々について同一であるから、以下では、断面で示した図１の（ｂ）に基づいて、各緩衝機構６０，７０，８０について、説明する。なお、図１の（ｂ）に示した例では、緩衝機構６０，７０，８０が周方向の同一個所に形成されているかの如く示されているけれども、配設個所の都合などを含めて所望ならば、緩衝機構６０，７０，８０のうち一種類又は全てが周方向の異なる個所に形成されていてもよい。更に、場合によっては、周方向の三箇所のうち一箇所又は二箇所において一種類又は全てが周方向の異なる個所に形成されていてもよい。更に、この例では、周方向の三箇所に各緩衝機構６０，７０，８０が形成されているとして説明するけれども、周方向の四箇所以上に各緩衝機構６０，７０，８０又は一部の緩衝機構が形成されていてもよい。加えて、緩衝機構６０，７０，８０が全て同数である代わりに、一種類又は二種類の緩衝機構が他の緩衝機構とは異なる数であってもよい。いずれにしても、各緩衝機構６０，７０，８０の数は、三箇所以上であることが好ましい。但し、配設個所の選択の都合等がある場合には、二箇所であってもよく、場合によっては、一箇所のみでもよい。その場合、残りの一箇所又は二箇所には、緩衝部材をハウジングとしての地板４などの静置部材４，５，６に対して静置・固定することにより、占有スペースを最小限に抑えるようにしてもよい。
【００３０】
緩衝機構６０は、てん輪２８の下面４６の外周縁部４７に対面する位置ないし部位において地板４に形成された円筒状ないし円柱状凹部６１と、該凹部６１内において軸線方向Ｆ１，Ｆ２に移動可能な円板状裏板６２と、裏板６２のうちてん輪２８の下面４６の外周縁部４７に対面する側の面６３に固着されたゴムや軟質樹脂の如き弾性材等からなる緩衝材６４と、裏板６２の背面６５に先端が固定され中間の雄ネジ部６６が地板４の凹部６１の底壁の雌ネジ部６７に螺合された調整ネジ部６８とを有する。
【００３１】
従って、調整ネジ部６８の頭部のネジ溝６９にドライバを係合させ該ドライバにより調整ネジ部６８をＥ１，Ｅ２方向に回すことにより、緩衝材６４をＦ１，Ｆ２方向に移動させ、緩衝材６４の表面６４ａをてん輪２８の対向面４７に近接・離間させ得る。
【００３２】
なお、緩衝材６４をてん輪２８に近接・離間させる構造は、他のどのようなものでもよく、図示の例においても、例えば、凹部６１及び裏板６２を角柱状にしておくと共に、調整ネジ部６８の先端を裏板６２に対して相対回転自在に裏板６２に係合させておいてもよい。
【００３３】
同様に、緩衝機構７０は、てん輪２８の外周面４８に対面する位置において地板４に形成された凹部７１と、該凹部７１内においててん輪の半径方向Ｇ１，Ｇ２に移動可能な裏板７２と、裏板７２のうちてん輪２８の周面４８に対面する側の面７３に固着されたゴムや軟質樹脂の如き弾性材等からなる緩衝材７４と、裏板７２の背面７５に先端が固定され中間の雄ネジ部７６が地板４の凹部７１の背面側壁部の雌ネジ部７７に螺合された調整ネジ部７８とを有する。
【００３４】
従って、この場合にも、調整ネジ部７８の頭部のネジ溝７９を利用して調整ネジ部７８をＨ１，Ｈ２方向に回すことにより、緩衝材６４をＧ１，Ｇ２方向に移動させ、緩衝材７４の表面７４ａをてん輪２８の外周面４８に近接・離間させ得る。
【００３５】
この場合にも、緩衝材７４をてん輪２８に近接・離間させる構造は、他のどのようなものでもよく、図示の例においても、例えば、凹部７１の下面を平面状にしておくと共に裏板７２を四角板状にしておき、調整ネジ部７８の先端を裏板７２に対して相対回転自在に裏板７２に係合させておいてもよい。
【００３６】
更に、同様に、緩衝機構８０は、てん輪２８の外周縁部に位置する環状本体部（リム部）２４の上面４９に対面する位置において地板４に形成された円筒状ないし円柱状凹部８１と、該凹部８１内において軸線方向Ｆ２，Ｆ１に移動可能な円板状裏板８２と、裏板８２のうちてん輪２８の環状本体部２４の上面４９に対面する側の面８３に固着された弾性材の如き緩衝材８４と、裏板８２の背面８５に先端が固定され中間の雄ネジ部８６が地板４の凹部８１の底壁の雌ネジ部８７に螺合された調整ネジ部８８とを有する。
【００３７】
従って、この場合にも、調整ネジ部８８の頭部のネジ溝８９を利用して調整ネジ部８８をＥ２，Ｅ１方向に回すことにより、緩衝材６４をＦ２，Ｆ１方向に移動させ、緩衝材８４の表面８４ａをてん輪２８の対向面４９に近接・離間させ得る。
【００３８】
なお、この場合にも、緩衝材８４をてん輪２８に近接・離間させる構造は、他のどのようなものでもよく、図示の例においても、例えば、凹部８１及び裏板８２を角柱状にしておくと共に、調整ネジ部８８の先端を裏板８２に対して相対回転自在に裏板８２に係合させておいてもよい。
【００３９】
以上の如く構成されたてん輪構造体１を備えた調速機構２を有する機械式時計３では、例えば、時計１を誤って床や地上に落とした場合でも、てん輪構造体１が動作不能になるような損傷を受ける虞れを最低限に抑えうる。
【００４０】
すなわち、例えば、時計３を誤って地面などに落とした場合で、時計３が、例えば、Ｇ１方向に地面などにぶつかった場合、てん真２３及びてん輪２８等を含むてんぷ構造体本体ないしてんぷ本体としてのてんぷ２０には、Ｇ２方向の衝撃が慣性力Ｋとして時計３に加えられることになる。てん輪２８のリム部２４はてんぷ２０に比較的大きい中心軸線Ｃのまわりの慣性モーメントを付与し得るように比較的大きな質量を有するから、てん輪２８のアーム部２５の中央部に固定されたリム部２４の比較的大きなＧ２方向慣性力Ｋがそのままてん真２３にかかる。
【００４１】
ここで、仮に、緩衝機構７０がないと想定（仮定）すると、その衝撃荷重Ｋの反作用力が、軸受１０ａ，１０ｂのてんぷ穴石１４ａ，１４ｂからてん真２３の両端の細い小径軸部２２，２１にＧ１方向にかかることになる。その結果、軸部２２や２１が折れたり曲がったりする虞れがあることになる。ところが、この時計３では、てんぷ２０の外周面４８にＧ２方向に近接した位置に緩衝材７４を備えた緩衝機構７０が配置されているので、てんぷ２０がＧ２方向にわずかに移動されると、てんぷ２０のてん輪２４の外周面７５が緩衝材７４に接触し更に押付けられる。なお、図１の（ａ）や（ｂ）では、見易さのために、表面４８，７４ａの間に比較的大きい間隙があるかのごとく示されているけれども、実際には、小径軸部２２，２１に大きな荷重がかかる前に荷重を受け得るように、この間隙は十分に小さい。従って、てんぷ２０のＧ２方向移動は、緩衝材７４が圧縮変形されるように変形されることにより、支えられ、Ｇ２方向の移動エネルギが吸収されることになる。従って、この時計３では、てんぷ構造体１のてんぷ２０の細い軸部２２，２１に過度な力がかかるのを避け得、軸部２２，２１が損傷を受ける虞れを最低限に抑え得る。
【００４２】
時計３が地面などにぶつかる方向が、Ｇ１方向ではなくて、別の半径方向であった場合でも、周方向の三箇所にある緩衝機構７０，７０，７０のうちのいずれか一つ又は二つの緩衝機構７０，７０が、該衝突に伴う衝撃を同様に支え得るから、てんぷ２０が動作不能になったり動作不良になるような損傷をてん真２３の小径軸部２１，２２が受ける虞れが少ない。
【００４３】
一方、時計３がＦ１方向やＦ２方向に落下して地面などにぶつかった場合にも、仮に、緩衝機構８０や６０がない場合には、軸部２２や２１が受石１５ａや１５ｂに強く押し付けられて、損傷を受ける虞れがあるけれども、緩衝機構６０，８０を備えたてんぷ構造体１を有する時計３では、軸部２２や２１が受石１５ａや１５ｂに強く押し付けられる前に、緩衝機構８０の緩衝部材８４や緩衝機構６０の緩衝部材６４がてんぷ２０の対向面４９や４７に接触して圧縮変形される際にその衝撃エネルギを吸収し得るから、軸部２２や２１が受石１５ａや１５ｂに強く押し付けられる虞れが少なく、てんぷ２０が動作不能になったり動作不良になるような損傷をてん真２３の小径軸部２１，２２が受ける虞れが少ない。
【００４４】
更に、時計３が、任意の向きで落下して地面などにぶつかった場合にも、緩衝機構６０，７０，８０を欠くときには、てんぷ２０の軸部２１，２２等が上記のいずれかの理由により損傷を受ける虞れがあるけれども、緩衝機構６０，７０，８０を備えたてんぷ構造体１を有する時計３では、軸部２２や２１が穴石１４ａ，１４ｂや受石１５ａ又は１５ｂに強く押し付けられる前に、緩衝機構７０，８０，６０のうちのいずれか二つ又は複数の緩衝部材７４，８４，６４がてんぷ２０の対向面４８や４９や４７に接触して圧縮変形される際にその衝撃エネルギを吸収し得るから、軸部２２や２１が穴石１４ａ，１４ｂや受石１５ａ又は１５ｂに強く押し付けられる虞れが少なく、てんぷ２０が動作不能になったり動作不良になるような損傷を軸部２１，２２が受ける虞れが少ない。
【００４５】
なお、このてんぷ構造体１では、緩衝機構６０，７０，８０の緩衝材６４，７４，８４の位置が調整可能であるから、てんぷ２０の質量やてんぷ２０の構造及び強度や軸受１０ａ，１０ｂの構造及び強度等に応じて、各緩衝材６４，７４，８４とてんぷ２０の対向面４７，４８，４９との間隔を適切な位置に調整し得るから、てんぷ２０が動作不能になったり動作不良になるような損傷を軸部２１，２２が受ける虞れを最低限に抑え得る。
【００４６】
図１の（ａ）及び（ｂ）で示した第一実施例の場合、緩衝機構６０，７０，８０の緩衝材６４，７４，８４は、てんぷ２０に対向する表面６４ａ，７４ａ，８４ａが平坦であるけれども、その代わりに、図２に第二実施例として示したように、横断面が先細の台形状の緩衝材１６４，１７４，１８４を備えていてもよい。この緩衝材１６４，１７４，１８４を備えた緩衝機構１６０，１７０，１８０を有するてんぷ構造体１０１を含む調速機構１０２を具備する機械式時計１０３は、緩衝材の形状が異なる点を除いて、図１のてんぷ構造体１を含む調速機構２を具備する機械式時計３と同様に構成されている。従って、第一実施例の部材や部位と同一又は同様な部材や部位は、図１と同一の符号で示されている。
【００４７】
この第二実施例のてんぷ構造体１０１を備えた時計１０３では、緩衝材１６４，１７４，１８４が先細になっているから、てんぷ２０にかかる衝撃が比較的小さい場合には、てんぷ２０の表面４７や４８や４９が対向表面１６４ａや１７４ａや１８４ａに軽く押し付けられた際にてんぷ２０がうける緩衝力が比較的小さく抑えられ得る。その結果、常時往復回動しているてんぷ２０の表面４７や４８や４９が対向表面１６４ａや１７４ａや１８４ａに接触するだけで、突然に比較的大きな摩擦力をうけることを避け得るから、てんぷ２０にかかる衝撃が比較的小さい場合には、てんぷ２０の往復回動動作が急激に妨げられるのを最低限に抑え得る。なお、この場合にも、てんぷ２０にかかる衝撃力が大きい場合には、てんぷ２０の表面４７や４８や４９が対応する緩衝機構１６０や１７０や１８０の対向表面１６４ａや１７４ａや１８４ａに比較的強く押し付けられるので、てんぷ２０のてん真２３の小径軸部２１，２２などが損傷を受ける虞れを最低限に抑え得る。また、このてんぷ構造体１では、緩衝部材１６４，１７４，１８４が先細であるから、スペースの占有を最小限にコンパクトに配置し得る。
【００４８】
緩衝材は、断面形状が図２に示したように台形である代わりに、第三実施例として図３に示したように、断面形状がかまぼこ型であってもよい。すなわち、図３には、断面形状がかまぼこ型の緩衝材２６４，２７４，２８４を備えた緩衝機構２６０，２７０，２８０を有するてんぷ構造体２０１を含む調速機構２０２を具備する機械式時計２０３が示され、この機械式時計２０３は、緩衝材の形状が異なる点を除いて、図１のてんぷ構造体１を含む調速機構２を具備する機械式時計３や図２のてんぷ構造体１０１を含む調速機構１０２を具備する機械式時計１０３と同様に構成されている。従って、第一実施例の部材や部位と同一又は同様な部材や部位は、図１と同一の符号で示されている。
【００４９】
この第三実施例のてんぷ構造体２０１を備えた時計２０３では、緩衝材２６４，２７４，２８４が先端まで先細になり且つ先端が丸みをおびて凸状に湾曲しているから、第二実施例のてんぷ構造体１０１の場合と同様に、てんぷ２０にかかる衝撃が比較的小さい場合には、てんぷ２０の表面４７や４８や４９が対向表面２６４ａや２７４ａや２８４ａの先端の凸状湾曲表面部分２６４ｂや２７４ｂや２８４ｂに最小限の範囲で軽く押し付けられるから、てんぷ２０がうける緩衝力が極力小さく抑えられ得る。その結果、常時往復回動しているてんぷ２０の表面４７や４８や４９が対向表面２６４ａや２７４ａや２８４ａに接触するだけで、突然に比較的大きな摩擦力をうけることを避け得、且つ対向表面２６４ａや２７４ａや２８４ａの先端２６４ｂや２７４ｂや２８４ｂが滑らかに凸状に湾曲しているから緩衝材２６４や２７４や２８４の表面をこじる虞れも最低限に抑えられ、てんぷ２０にかかる衝撃が比較的小さい場合には、てんぷ２０の往復回動動作が妨げられるのを最低限に抑え得る。なお、この場合にも、てんぷ２０にかかる衝撃力が大きい場合には、てんぷ２０の表面４７や４８や４９が対応する緩衝機構２６０や２７０や２８０の対向表面２６４ａや２７４ａや２８４ａに比較的強く押し付けられるので、てんぷ２０のてん真２３の小径軸部２１，２２などが損傷を受ける虞れを最低限に抑え得る。
【００５０】
ここで、緩衝材２６４，２７４，２８４の断面形状に関して、「かまぼこ型」とは、てんぷ２０の対向表面４７，４８，４９に向かって滑らかな凸状に湾曲して中央部が突出していることをいい、典型的には、半円形であるけれども、円の一部でも、楕円の一部のように部位によって曲率が異なっていてもよい。ここで、立体的形状は、半円筒形状でもドーム状でもよい。
【００５１】
なお、例えば、てんぷ２０の複数の表面に対向配置されるべき二つの緩衝材が一体に形成されていてもよい。図４では、断面がＬ字型の緩衝材３９４をてんぷ２０の表面４７及び周面４８に対向配置し、且つ位置調整可能に支える緩衝機構３９０を備えたてんぷ構造体３０１を有する調速機構３０２を含む機械式時計３０３が示されている。
【００５２】
てんぷ構造体３０１では、緩衝機構３９０は、Ｌ字型断面の緩衝材３９４と、該緩衝材３９４を支えるＬ字型断面の裏板３９２であって半径方向延在背面３６５に半径方向に延びた蟻溝３６５ａを備え軸線方向延在背面３７５に軸線方向と平行に延びた蟻溝３７５ａを備えるもの（裏板）３９２と、中間の雄ネジ部３６６で地板４の凹部３９１の底壁の雌ネジ部３６７に螺合され先端の大径部３６８ａが蟻溝３６５ａに係合された軸線方向位置調整ネジ部３６８と、中間の雄ネジ部３７６で地板４の凹部３９１の壁部の雌ネジ部３７７に螺合され先端の大径部３７８ａが蟻溝３７５ａに係合された半径方向位置調整ネジ部３７８とを有する。この緩衝機構３９０の場合、軸線方向位置調整ネジ部３６８の頭部のネジ溝３６９を利用して調整ネジ部３６８をＥ１，Ｅ２方向に回すことにより、緩衝材３９４をＦ１，Ｆ２方向に移動させ、てん輪２８の対向面４７に近接・離間させ得る。このとき、半径方向位置調整ネジ部３７８の先端大径部３７８ａは裏板３９２の蟻溝３７５ａ内で裏板３９２に対してＦ２，Ｆ１方向に相対移動される。この緩衝機構３９０の場合、また、半径方向位置調整ネジ部３７８の頭部のネジ溝３７９を利用して該ドライバにより調整ネジ部３７８をＨ１，Ｈ２方向に回すことにより、緩衝材３９４をＧ１，Ｇ２方向に移動させ、てん輪２８の対向面４８に近接・離間させ得る。このとき、軸線方向位置調整ネジ部３６８の先端大径部３６８ａは裏板３９２の蟻溝３６５ａ内で裏板３９２に対してＧ２，Ｇ１方向に相対移動される。
【００５３】
この場合には、緩衝機構の数を減少させ得る。但し、二軸方向に位置調整可能にするための構造は、他の構造でもよい。
【図面の簡単な説明】
【図１】本発明による好ましい第一実施例のてんぷ構造体を備えた機械式時計の調速機構の部分を示したもので、（ａ）は平面説明図、（ｂ）は（ａ）のＩＢ−ＩＢ線断面説明図（但し、てんわより上のひげ持部分はＩＢ−ＩＢａ線断面）。
【図２】本発明による好ましい第二実施例のてんぷ構造体を備えた機械式時計の調速機構の部分に関する図１の（ｂ）と同様な断面説明図。
【図３】本発明による好ましい第三実施例のてんぷ構造体を備えた機械式時計の調速機構の部分に関する図１の（ｂ）と同様な断面説明図。
【図４】本発明による好ましい第四実施例のてんぷ構造体を備えた機械式時計の調速機構の部分に関する図１の（ｂ）と同様な断面説明図。
【符号の説明】
１，１０１，２０１，３０１ てんぷ構造体
２，１０２，２０２，３０２ 調速機構
３，１０３，２０３，３０３ 機械式時計
４ 地板
５，６ 中枠
１０，１０ａ，１０ｂ 軸受
２０ てんぷ（てんぷ本体）
２１，２２ 小径軸部
２３ てん真
２４ リム部（てん輪本体）
２５ アーム部
２８ てん輪
３０ ひげ玉
３３ ひげ持
３５ ひげぜんまい
４０ 振り座
４５ 緩急針
４７，４９ 対向面（外周縁部近傍面）
４８ 外周面
５０ アンクル
５２ アンクルさお
５５ 入りづめ
５６ 出づめ
５７ ガンギ車
６０，７０，８０，１６０，１７０，１８０，２６０，２７０，２８０，３９０緩衝機構
６１，７１，８１ 凹部
６２，７２，８２，３９２ 裏板
６４，７４，８４，１６４，１７４，１８４，２６４，２７４，２８４，３９４緩衝材
６８，７８，８８，３６８，３７８ 調整ネジ部
Ｆ１，Ｆ２，Ｇ１，Ｇ２ 移動方向[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a balance structure and a mechanical timepiece provided with the balance structure.
[0002]
[Prior art]
In mechanical watches, it is known to adjust or define the speed of the incremental rotation of the escape wheel by means of a balance with the ankle.
[0003]
The balance with hairspring (main body) includes a balance wheel having a ring-shaped or annular rim portion, and a balance that supports the balance wheel via an arm portion of the balance wheel and serves as a rotation center axis, and is mounted on the housing. As a result, the shaft is supported reciprocally rotatable by the thin shaft portions at both ends of the balance. Under the action of the spring force of the hairspring fixed at the inner peripheral end to the beard ball fixed to the balance at the inner peripheral end and fixed at the outer peripheral end to the beard holder, and the ankle that interferes with the rock of the balance spring, the balance wheel is It is reciprocated.
[0004]
[Problems to be solved by the invention]
If such a mechanical timepiece is accidentally dropped on the floor or the ground, or an unexpected external force is applied to the mechanical timepiece, a relatively large inertia is applied to the rim of the balance wheel having a large mass so as to give a moment of inertia to the balance. The force is applied as an impact, and this inertial force is applied to the balance. There is a possibility that the balance may be damaged, such as the balance being broken at the thin shaft portions at both ends.
[0005]
In the case of an eccentric weight-driven timepiece that drives a mainspring and a generator by swinging the eccentric weight, the eccentric weight has an eccentric weight to rapidly attenuate the axial vibration of the eccentric weight due to a relatively small impact applied to the eccentric weight. It has been proposed to provide an elastic material for vibration suppression in the vicinity (Patent Document 1).
[0006]
[Patent Document 1]
JP-A-2002-311161 (pages 6 to 9, FIG. 1)
[0007]
However, the use of the elastic material in the proposal of the patent document aims at damping the vibration of the eccentric weight. Note that, in Patent Literature 1, the displacement of the eccentric weight due to a large impact is intended to be restricted by other means such as friction braking.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a balance structure having a small risk of being damaged so as to be inoperable even when subjected to a large impact, and a machine provided with the balance structure. To provide a formula clock.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the balance structure of the present invention surrounds the balance with the balance with the balance with the balance with the balance with the balance with the balance with the balance with the balance with the balance with the balance. And a cushioning member mounted on a portion of the housing facing the rim portion of the balance wheel, and for restricting a displacement of the rim portion of the balance wheel from a predetermined position.
[0010]
According to the balance structure of the present invention, it is preferable that a rim of the balance wheel be mounted on a portion of the housing that supports the balance that supports the balance with the balance to reciprocate and rotatably surrounds the balance balance body, and that is mounted on a portion of the housing that faces the rim portion of the balance wheel. Since the cushioning material for restricting the displacement of the rim portion from the predetermined position of the portion is provided, the displacement of the rim portion of the balance wheel from the predetermined position due to the impact can be regulated by the cushioning material and fixed to the balance wheel. The deviation of the balance from the predetermined position may be prohibited. Therefore, there is little possibility that an excessive force is applied between the thin shaft portion and the bearing thereof, and there is little possibility that the thin shaft portion or the like is broken by an impact and is inoperable.
[0011]
Here, the main body of the housing may be any member as long as it can support the balance with the balance in a reciprocating manner, and is typically mounted on the outer frame of a mechanical timepiece such as a main plate, a middle frame, or an outer frame. It is made of a member that is immovable. Regarding the housing, `` surrounding '' the balance with the balance with hairspring means that the balance is around the balance with the balance with the cushioning material at a predetermined position facing the rim of the balance with hair. No need.
[0012]
The cushioning material may be of any material or structure as long as it can sufficiently reduce the impact force applied to the balance wheel, but is typically formed of a material such as rubber or soft synthetic resin.
[0013]
Although the cushioning material may be stationary or fixed to the housing with respect to the housing, it is typically mounted on the housing so as to be positionally adjustable with respect to the housing. In this case, the size of the gap between the rim portion of the balance wheel and the cushioning material can be adjusted to the minimum (to the extent necessary), so that the risk that the balance with hairspring structure is damaged by impact can be minimized. Will be possible.
[0014]
Although the cushioning material may be configured to regulate any deviation exceeding a predetermined size from a position taken by the rim portion of the balance wheel during normal reciprocating rotation, typically,
(1) a portion of the housing that faces the annular end surface of the rim portion of the balance wheel; and
(2) A portion of the housing that faces the outer peripheral surface of the rim portion of the balance wheel.
Is attached to at least one of the parts.
[0015]
In the former case (1), the balance of the balance with hairspring moves in a direction along the axial direction of the balance with hairspring, or the inclination of the balance with the extension surface of the balance with hair deviates from a direction perpendicular to the direction connecting the bearings on both sides. That is, the rim portion, inclination and deformation of the balance wheel can be suppressed.
[0016]
On the other hand, in the latter case (2), the rim portion of the balance wheel shifts radially from the position connecting the bearings on both sides, and the balance that forms the central axis of the balance structure shifts radially from the position connecting the bearings on both sides. Can be suppressed.
[0017]
The cushioning material may be, for example, annular, circular, cylindrical, or the like, but typically, a plurality of cushioning materials are mounted at intervals along the circumferential direction of the rim portion of the balance wheel. Thereby, even if the shape and the dimensional accuracy of the cushioning material are not so high, they can be individually arranged and positioned. Further, when the position adjustment of the cushioning material is performed, the position adjustment is easily performed.
[0018]
The cushioning material may have any shape as long as the displacement of the rim portion of the balance wheel can be controlled, and typically, the surface portion of the cushioning material facing the rim portion of the balance wheel is substantially formed. It may be planar in nature, but may instead taper toward the opposing surface portion of the balance wheel. In this case, the cross-sectional shape of the cushioning material is trapezoidal or kamaboko-shaped. Here, the kamaboko type is typically semicircular, but the curvature of the bay surface may not be constant.
[0019]
The cushioning material may have an L-shaped cross section. In this case, one leg of the L faces the outer peripheral surface of the rim of the balance wheel, and the other leg of the cushion has a rim of the balance wheel. It is arranged so as to face the annular end face of the part.
[0020]
In the mechanical timepiece of the invention, by providing the balance structure as described above, the risk that the balance structure is damaged by an impact can be minimized.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Some preferred embodiments of the present invention will be described based on preferred embodiments shown in the accompanying drawings.
[0022]
【Example】
FIGS. 1A and 1B show a mechanical timepiece 3 having a speed control mechanism 2 including a balance structure 1 according to a first embodiment.
[0023]
The timepiece 3 includes housing parts 5 and 6 such as a base plate 4, a middle frame, and a wheel train receiving portion (supporting portion) that are rested against an outer frame (not shown) (hereinafter referred to as a middle frame for convenience). However, a part of the main plate 4 may be another stationary member such as a train wheel bridge or a balance with hairspring). In this example, the housing includes the main plate 4 and the middle frames 5 and 6.
[0024]
A main body of the balance with hairspring 1, that is, a balance with hairspring 20 as a balance with hairspring, is disposed between the main plate 4 and the middle frame 5 so as to be rotatable in the C1 and C2 directions around the central axis C.
[0025]
The balance with hairspring 20 is formed of upper and lower bearings 10a and 10b formed along the central axis C on the inner frame 5 and the base plate 4 (when the balance is not distinguished from the upper and lower balance bearings, the symbol is "10"). ), And at both ends are connected to the rim 23, which is rotatably supported around the central axis C at the narrow shaft portions 21 and 22 at both ends, an annular rim portion 24 forming a balance ring main body, and the rim portion 24. An arm 25 extending in the diameter direction of the rim 24 is provided. The arm 25 is fixed to a center shaft 27 of the balance bar 23 at an intermediate portion 26 of the arm 25, and is attached to an upper shaft 29 of the balance bar 23. A beard ball 30 provided, a hairspring or beard 35 attached to the beard ball 30 at an inner peripheral end 31 and attached to a beard holder 33 at an outer peripheral end 32, and large and small brim portions or flange portions 36, 37. When And a swing seat 40 attached to the lower shaft portion 39 of the true 23 you doing holds swing stone 38 at atmospheric flange portion 36.
[0026]
The balance upper bearing 10a serves as a journal bearing for the upper combined bearing frame 13a including the inner and outer bearing frames 11a and 12a, and the small-diameter shaft portion 22 at the upper end of the stem 23 disposed in the medium-diameter concave portion of the bearing frame 13a. A balance wheel top stone 14a that works, a balance top stone 15a that functions as a thrust bearing for the upper-end small-diameter shaft portion 22 of the balance bar 23 that is disposed in the large-diameter recess of the bearing frame 13a, and that is locked and received in a groove of the bearing frame 13a. A stone pressing spring 16a for holding the stone 15a in the bearing frame 13a is provided. The balance lower bearing 10b serves as a journal bearing for the lower combined bearing frame 13b including the inner and outer bearing frames 11b and 12b, and the lower end small diameter shaft portion 21 of the stem 23 disposed in the middle diameter recess of the bearing frame 13b. A balance wheel stone 14b that works, a balance wheel stone 15b that functions as a thrust bearing for the lower-end small-diameter shaft portion 21 of the balance bar 23 that is disposed in the large-diameter recess of the bearing frame 13b, and that is locked and received in a groove of the bearing frame 13b. And a stone receiving spring 16b for holding the stone 15b in the bearing frame 13b. Since the upper and lower bearings 10a and 10b are configured in the same manner, when they are not distinguished from each other or when they are collectively referred to, the members "11", "12", "13", and "14" are omitted from the members "a" and "b". , 15, 16 etc. However, the structure of the upper and lower swing seats 10a and 10b may be different from each other as long as the bearings 10a and 10b can support the balance bar 23 so as to be able to reciprocate around the central axis C.
[0027]
The beard holder 33 is fixed to a beard holder 41 that can be adjusted in position about the center axis C with respect to the middle frame 5 by a mounting screw 42. At the balance with the balance with hairspring 10a, a needle for supporting the needle 43 is mounted rotatably in the directions C1 and C2 around the central axis C. The slow / fast needle support arm 43 supports a slow / fast needle 45 in contact with the large-diameter portion 44 on the outer peripheral side of the hairspring 35 at its distal end. The slow / fast needle support arm 43 is rotated in the C1 and C2 directions to allow the slow / fast needle 45 to rotate. The effective length and spring constant of the hairspring 35 are changed by adjusting the position or location of the hairspring 35 in the C1 and C2 directions abutting on the large diameter portion 44 of the hairspring 35, so that the balance wheel 28 reciprocates in the C1 and C2 directions. The cycle of rotation (reciprocating rotation) can be adjusted.
[0028]
The swing stone 38 of the balance with hairspring 20 has an uncle in the form of a fork-shaped arm among the three arms 52, 53, 54 of the ankle 50 that can reciprocate in the directions D1 and D2 around the ankle stem 51. You 52 can engage. One of the remaining two arms 53, 54 of the pallet 50 is provided with a boss 55, and the other boss 54 is provided with a boss 56. The pallet is pivoted in the D1 and D2 directions by the rocking stone 38. 50 is engaged alternately with an escape tooth 58 of an escape wheel & pinion 57 which is rotated in the Q1 direction about the central axis Q, thereby being driven to rotate Q1 by a barrel (not shown). Stepwise rotation of the escape wheel & pinion 57 is allowed.
[0029]
The balance structure 1 further includes a first axial buffer mechanism 60 and a circumferential buffer mechanism 70 mounted on the main plate 4, and a second axial buffer mechanism 80 mounted on the middle frame 5. In the example shown in FIG. 1, three buffer mechanisms 60, 70, 80 are formed at substantially equal intervals in the circumferential direction around the central axis C. If there is a restriction on the arrangement space due to the arrangement of the other watch parts, the arrangement may not be exactly the same as shown in FIG. Since the three buffer mechanisms 60, 70, 80 formed in the circumferential direction are the same for each of the buffer mechanisms 60, 70, 80, the following description will be based on FIG. The respective buffer mechanisms 60, 70, 80 will be described. In the example shown in FIG. 1B, the buffer mechanisms 60, 70, 80 are shown as if they were formed at the same location in the circumferential direction. Then, one or all of the buffer mechanisms 60, 70, 80 may be formed at different locations in the circumferential direction. Further, depending on the case, one or all of the three or three locations in the circumferential direction may be formed at different locations in the circumferential direction. Further, in this example, the buffer mechanisms 60, 70, and 80 are described as being formed at three locations in the circumferential direction, but each of the buffer mechanisms 60, 70, and 80 or a part of the buffer mechanisms is provided at four or more locations in the circumferential direction. A mechanism may be formed. In addition, instead of having the same number of buffer mechanisms 60, 70, and 80, one or two types of buffer mechanisms may be different in number from other buffer mechanisms. In any case, the number of the buffer mechanisms 60, 70, 80 is preferably three or more. However, when there is a convenience in selecting the disposition location, two locations may be provided, and in some cases, only one location may be provided. In such a case, the occupied space can be minimized by resting and fixing the buffer member to the stationary members 4, 5, and 6 such as the base plate 4 as a housing at the remaining one or two locations. It may be.
[0030]
The cushioning mechanism 60 has a cylindrical or columnar concave portion 61 formed on the base plate 4 at a position or position facing the outer peripheral edge 47 of the lower surface 46 of the balance wheel 28, and moves in the concave portion 61 in the axial directions F1 and F2. A possible disk-shaped back plate 62 and a cushioning material made of an elastic material such as rubber or soft resin fixed to a surface 63 of the back plate 62 facing the outer peripheral edge 47 of the lower surface 46 of the balance wheel 28. 64, and an adjusting screw portion 68 having a front end fixed to the back surface 65 of the back plate 62 and an intermediate male screw portion 66 screwed to a female screw portion 67 on the bottom wall of the concave portion 61 of the base plate 4.
[0031]
Therefore, the buffer member 64 is moved in the F1 and F2 directions by engaging the driver with the screw groove 69 in the head of the adjustment screw portion 68 and turning the adjustment screw portion 68 in the E1 and E2 directions by the driver. The surface 64 a of the wheel 64 can be moved toward or away from the opposing surface 47 of the balance wheel 28.
[0032]
Note that any other structure may be used to move the cushioning material 64 toward and away from the balance wheel 28. In the illustrated example, for example, the concave portion 61 and the back plate 62 are formed in a prismatic shape, and the adjusting screw is adjusted. The tip of the portion 68 may be engaged with the back plate 62 so as to be rotatable relative to the back plate 62.
[0033]
Similarly, the buffer mechanism 70 includes a concave portion 71 formed in the base plate 4 at a position facing the outer peripheral surface 48 of the balance wheel 28, and a back plate 72 movable in the radial direction G1 and G2 of the balance wheel in the concave portion 71. And a cushioning member 74 made of an elastic material such as rubber or soft resin fixed to a surface 73 of the back plate 72 facing the peripheral surface 48 of the balance wheel 28, and a tip on a back surface 75 of the back plate 72. An intermediate screw portion 76 is fixed and has an adjustment screw portion 78 screwed to a female screw portion 77 on the rear side wall of the concave portion 71 of the base plate 4.
[0034]
Therefore, also in this case, the buffer 64 is moved in the G1 and G2 directions by turning the adjusting screw 78 in the H1 and H2 directions using the screw groove 79 in the head of the adjusting screw 78, and The surface 74 a of the base 74 can be moved toward or away from the outer peripheral surface 48 of the balance wheel 28.
[0035]
In this case as well, any other structure may be used to move the cushioning material 74 toward and away from the balance wheel 28. In the illustrated example, for example, the lower surface of the concave portion 71 is made flat and The front end of the adjusting screw portion 78 may be engaged with the back plate 72 so as to be rotatable relative to the back plate 72.
[0036]
Further, similarly, the buffer mechanism 80 includes a cylindrical or columnar concave portion 81 formed on the base plate 4 at a position facing the upper surface 49 of the annular main body (rim) 24 located at the outer peripheral edge of the balance wheel 28. A disc-shaped back plate 82 movable in the axial directions F2 and F1 in the concave portion 81, and a surface 83 of the back plate 82 on the side facing the upper surface 49 of the annular main body 24 of the balance wheel 28. A cushioning material 84 such as an elastic material; an adjusting screw portion 88 having a front end fixed to the back surface 85 of the back plate 82 and an intermediate male screw portion 86 screwed into a female screw portion 87 on the bottom wall of the concave portion 81 of the main plate 4. Having.
[0037]
Therefore, also in this case, the buffer 64 is moved in the F2 and F1 directions by turning the adjusting screw 88 in the E2 and E1 directions by using the screw groove 89 in the head of the adjusting screw 88, and thereby moving the cushioning material. The surface 84 a of 84 can be moved toward or away from the opposing surface 49 of the balance wheel 28.
[0038]
Also in this case, any other structure may be used for moving the cushioning material 84 toward and away from the balance wheel 28. In the illustrated example, for example, the concave portion 81 and the back plate 82 are formed in a prism shape. At the same time, the tip of the adjustment screw 88 may be engaged with the back plate 82 so as to be rotatable relative to the back plate 82.
[0039]
In the mechanical timepiece 3 having the speed control mechanism 2 including the balance structure 1 configured as described above, for example, even if the timepiece 1 is accidentally dropped on the floor or the ground, the balance structure 1 cannot operate. The danger of suffering such damage can be minimized.
[0040]
That is, for example, when the timepiece 3 is accidentally dropped on the ground or the like, and when the timepiece 3 collides with the ground or the like in the G1 direction, for example, the balance structure main body including the balance wheel 23 and the balance wheel 28 is not used. As a result, an impact in the G2 direction is applied to the timepiece 3 as an inertial force K. Since the rim portion 24 of the balance wheel 28 has a relatively large mass so as to impart a relatively large moment of inertia about the center axis C to the balance with hairspring 20, it is fixed to the center of the arm portion 25 of the balance wheel 28. A relatively large inertia force K in the G2 direction of the rim portion 24 is directly applied to the balance 23.
[0041]
Here, assuming that the shock absorber 70 is not provided (assumed), the reaction force of the impact load K is reduced from the balance holes 14a, 14b of the bearings 10a, 10b to the small small-diameter shaft portions 22, at both ends of the balance 23. 21 is applied in the G1 direction. As a result, the shaft portions 22 and 21 may be broken or bent. However, in this timepiece 3, since the buffer mechanism 70 provided with the cushioning member 74 is disposed at a position close to the outer peripheral surface 48 of the balance with hairspring 20 in the direction G2, if the balance with hairspring 20 is slightly moved in the direction G2, The outer peripheral surface 75 of the balance wheel 24 of the balance with hairspring 20 contacts the cushioning material 74 and is further pressed. Although FIGS. 1A and 1B show a relatively large gap between the surfaces 48 and 74a for the sake of clarity, the small diameter shaft portion is actually shown. This gap is small enough so that it can be loaded before the heavy loads on 22, 21 are applied. Accordingly, the movement of the balance with hairspring 20 in the G2 direction is supported by the deformation of the cushioning member 74 so as to be compressed and deformed, and the movement energy in the G2 direction is absorbed. Therefore, in this timepiece 3, it is possible to avoid applying excessive force to the thin shaft portions 22, 21 of the balance with hairspring 20 of the balance with hairspring 1, and to minimize the possibility that the shaft portions 22, 21 are damaged.
[0042]
Even if the direction in which the timepiece 3 hits the ground or the like is not the G1 direction but a different radial direction, any one or two of the buffer mechanisms 70, 70, 70 at the three circumferential positions are provided. Since the shock absorbing mechanisms 70 and 70 can similarly support the impact caused by the collision, the small-diameter shaft portions 21 and 22 of the balance stem 23 may be damaged so that the balance with hairspring 20 becomes inoperable or malfunctions. Few.
[0043]
On the other hand, when the timepiece 3 falls in the F1 direction or the F2 direction and hits the ground or the like, if the shock absorbers 80 and 60 are not provided, the shaft portions 22 and 21 are strongly pressed against the receiving stones 15a and 15b. The watch 3 having the balance with hairspring 1 provided with the shock absorbing mechanisms 60 and 80 may be damaged by the shock absorbing mechanism before the shafts 22 and 21 are strongly pressed against the receiving stones 15a and 15b. When the cushioning member 84 of the buffer mechanism 80 and the cushioning member 64 of the cushioning mechanism 60 come into contact with the opposing surfaces 49 and 47 of the balance with hairspring 20 and are compressed and deformed, the impact energy can be absorbed. The small-diameter shaft portions 21 and 22 of the balance bar 23 are less likely to be strongly pressed against the balance 15 or 15b, and are less likely to be damaged such that the balance 20 becomes inoperable or malfunctions.
[0044]
Furthermore, even when the timepiece 3 falls in an arbitrary direction and hits the ground or the like, when the buffer mechanism 60, 70, 80 is missing, the shaft portions 21, 22, etc. of the balance with hairspring 20 are removed for any of the above reasons. Although there is a risk of damage, in the timepiece 3 having the balance with hairspring structure 1 including the buffer mechanisms 60, 70, and 80, the shaft portions 22 and 21 are strongly pressed against the pit stones 14a and 14b and the receiving stones 15a and 15b. Previously, when any two or more of the buffering mechanisms 70, 80, 60 contact the opposing surfaces 48, 49, and 47 of the balance with hairspring 20 and are compressed and deformed, Since energy can be absorbed, there is little possibility that the shaft portions 22 and 21 are strongly pressed against the stones 14a and 14b and the receiving stones 15a and 15b, and damage to the balance with hairspring 20 becoming inoperable or malfunctioning is reduced. 21 and 22 is the possibility is small to receive.
[0045]
In the balance with hairspring 1, since the positions of the cushioning members 64, 74, 84 of the cushioning mechanisms 60, 70, 80 can be adjusted, the mass of the balance with hairspring 20, the structure and strength of the balance with hairspring 20, and the strength of the bearings 10 a, 10 b. Depending on the structure, strength, etc., the distance between each cushioning material 64, 74, 84 and the opposing surface 47, 48, 49 of the balance with hairspring 20 can be adjusted to an appropriate position, so that the balance with hairspring 20 becomes inoperable or malfunctions. Thus, the risk that the shaft portions 21 and 22 may be damaged can be minimized.
[0046]
In the case of the first embodiment shown in FIGS. 1A and 1B, the cushioning members 64, 74, 84 of the cushioning mechanisms 60, 70, 80 have flat surfaces 64a, 74a, 84a facing the balance with hairspring 20. Alternatively, as shown in FIG. 2 as a second embodiment, trapezoidal cushioning members 164, 174, 184 having a tapered cross section may be provided. The mechanical timepiece 103 including the speed control mechanism 102 including the balance with hairspring structure 101 having the buffer mechanisms 160, 170, and 180 provided with the cushioning materials 164, 174, and 184, except that the shape of the cushioning material is different. It is configured similarly to a mechanical timepiece 3 having a speed control mechanism 2 including a balance structure 1 of FIG. Therefore, members or portions that are the same as or similar to those of the first embodiment are denoted by the same reference numerals as in FIG.
[0047]
In the timepiece 103 having the balance with hairspring structure 101 according to the second embodiment, the cushioning members 164, 174, and 184 are tapered, so that when the impact on the balance with hairspring 20 is relatively small, the surface 47 of the balance with hairspring 20 can be used. When the springs 48 and 49 are slightly pressed against the opposing surfaces 164a, 174a and 184a, the buffering force applied to the balance 20 can be suppressed to a relatively small value. As a result, the surface 47, 48, or 49 of the balance with the balance being constantly reciprocated can be prevented from suddenly receiving a relatively large frictional force only by contacting the opposing surfaces 164a, 174a, and 184a. When the impact on the balance is relatively small, it is possible to minimize the sudden hindrance of the reciprocating rotation of the balance with hairspring 20. Also in this case, when the impact force applied to the balance with hairspring 20 is large, the surfaces 47, 48, and 49 of the balance with hairspring 20 are relatively strong against the opposing surfaces 164a, 174a, and 184a of the corresponding buffer mechanisms 160, 170, and 180. Since it is pressed, the possibility that the small diameter shaft portions 21 and 22 of the balance bar 23 of the balance with hairspring 20 are damaged can be minimized. Further, in the balance with hairspring 1, the cushioning members 164, 174, 184 are tapered, so that the space occupation can be minimized and compactly arranged.
[0048]
Instead of having a trapezoidal cross section as shown in FIG. 2, the cushioning material may have a semi-cylindrical cross section as shown in FIG. 3 as a third embodiment. That is, FIG. 3 shows a mechanical timepiece 203 provided with a speed control mechanism 202 including a balance with hairspring structure 201 having buffer mechanisms 260, 270, and 280 provided with buffer members 264, 274, and 284 having a cross section of a semi-cylindrical shape. This mechanical timepiece 203 is different from the mechanical timepiece 3 including the balance mechanism 2 including the balance structure 1 of FIG. 1 and the balance structure 101 of FIG. 2 except that the shape of the cushioning material is different. The configuration is the same as that of a mechanical timepiece 103 including a speed control mechanism 102 including a speed control mechanism. Therefore, members or portions that are the same as or similar to those of the first embodiment are denoted by the same reference numerals as in FIG.
[0049]
In the timepiece 203 having the balance structure 201 according to the third embodiment, the cushioning materials 264, 274, and 284 are tapered to the tip and the tip is rounded and convexly curved. As in the case of the balance with hairspring structure 101, when the impact on the balance with hairspring 20 is relatively small, the surface 47, 48, or 49 of the balance with hairspring 20 has the convex curved surface portion 264b at the tip of the opposing surface 264a, 274a, or 284a. 274b and 284b can be lightly pressed in the minimum range, so that the buffering force applied to the balance with hairspring 20 can be suppressed as small as possible. As a result, the surface 47, 48, or 49 of the balance 20 which is always reciprocating can contact the opposing surface 264a, 274a, or 284a only to avoid suddenly receiving a relatively large frictional force. Since the tips 264b, 274b, and 284b of the H.264a, 274a, and 284a are smoothly curved in a convex shape, the risk of prying the surface of the cushioning material 264, 274, or 284 is minimized, and the impact on the balance with hairspring 20 is compared. When the balance is extremely small, hindrance to the reciprocating rotation of the balance with hairspring 20 can be minimized. Also in this case, when the impact force applied to the balance with hairspring 20 is large, the surfaces 47, 48, and 49 of the balance with hairspring 20 are relatively strong against the opposing surfaces 264a, 274a, and 284a of the corresponding buffer mechanisms 260, 270, and 280. Since it is pressed, the possibility that the small diameter shaft portions 21 and 22 of the balance bar 23 of the balance with hairspring 20 are damaged can be minimized.
[0050]
Here, with respect to the cross-sectional shape of the cushioning materials 264, 274, 284, the term “kamaboko type” means that the central portion protrudes smoothly toward the opposing surfaces 47, 48, 49 of the balance with hairspring 20. Although it is typically a semicircle, the curvature may be different depending on a part such as a part of a circle or a part of an ellipse. Here, the three-dimensional shape may be a semi-cylindrical shape or a dome shape.
[0051]
Note that, for example, two cushioning members to be disposed to face each other on a plurality of surfaces of the balance with hairspring 20 may be integrally formed. In FIG. 4, a governing mechanism 302 having a balance structure 301 having a balance mechanism 390 which has a cushioning mechanism 390 which is arranged so as to oppose the cushioning material 394 having an L-shaped cross section to the surface 47 and the peripheral surface 48 of the balance with hairspring 20 and supports the position thereof in an adjustable manner. Is shown.
[0052]
In the balance with hairspring structure 301, the buffer mechanism 390 includes a cushioning member 394 having an L-shaped cross section and a back plate 392 having an L-shaped cross section that supports the cushioning member 394, and extends radially to a rear surface 365 extending in a radial direction. A dovetail groove 375a provided with a dovetail groove 365a and a dovetail groove 375a extending in parallel to the axial direction on a back surface 375 (back plate) 392, and a female screw at the bottom wall of the concave portion 391 of the base plate 4 with an intermediate male screw portion 366. A large-diameter portion 368a at the tip is engaged with the dovetail groove 365a, and an axial position adjusting screw portion 368 is screwed into the portion 367. A female screw portion 377 on the wall of the concave portion 391 of the base plate 4 is provided with an intermediate male screw portion 376. And a large-diameter portion 378a at the distal end thereof is engaged with a dovetail groove 375a. In the case of the buffer mechanism 390, the buffer member 394 is moved in the F1 and F2 directions by turning the adjusting screw portion 368 in the E1 and E2 directions using the screw groove 369 of the head of the axial position adjusting screw portion 368. , Can be made to approach or separate from the opposing surface 47 of the balance wheel 28. At this time, the large-diameter portion 378a at the distal end of the radial position adjusting screw portion 378 is moved relative to the back plate 392 in the F2 and F1 directions within the dovetail groove 375a of the back plate 392. In the case of the buffer mechanism 390, the screw 394 is rotated in the H1 and H2 directions by the driver using the screw groove 379 of the head of the radial position adjustment screw 378, so that the buffer 394 is moved to G1 and G2. It can be moved in the G2 direction to approach or separate from the opposing surface 48 of the balance wheel 28. At this time, the large-diameter portion 368a of the distal end of the axial position adjusting screw portion 368 is moved relative to the back plate 392 in the G2 and G1 directions within the dovetail groove 365a of the back plate 392.
[0053]
In this case, the number of buffer mechanisms can be reduced. However, the structure for enabling the position adjustment in the biaxial direction may be another structure.
[Brief description of the drawings]
1A and 1B show a portion of a speed control mechanism of a mechanical timepiece provided with a balance structure according to a first preferred embodiment of the present invention, wherein FIG. 1A is an explanatory plan view and FIG. 1B is a plan view of FIG. IB-IB line cross-sectional explanatory view (however, the whisker above the balance is the IB-IBa line cross section).
FIG. 2 is a cross-sectional explanatory view similar to FIG. 1B, showing a portion of a speed control mechanism of a mechanical timepiece provided with a balance structure according to a second preferred embodiment of the present invention.
FIG. 3 is an explanatory sectional view similar to FIG. 1 (b), showing a portion of a speed control mechanism of a mechanical timepiece provided with a balance structure according to a third preferred embodiment of the present invention.
FIG. 4 is an explanatory sectional view similar to FIG. 1 (b), showing a portion of a speed control mechanism of a mechanical timepiece provided with a balance structure according to a fourth preferred embodiment of the present invention.
[Explanation of symbols]
1,101,201,301 Balance structure
2,102,202,302 Governing mechanism
3,103,203,303 Mechanical watches
4 Ground plate
5, 6 middle frame
10, 10a, 10b bearing
20 balance (balance body)
21,22 small diameter shaft
23 Tenshin
24 Rim (balance body)
25 Arm
28 Balance wheel
30 Beard Ball
33 Beard
35 Hairspring
40 Pisces
45 Needle
47,49 Opposing surface (surface near the outer peripheral edge)
48 Outer surface
50 ankles
52 Uncle Sao
55 Entering
56 First
57 escape wheel
60, 70, 80, 160, 170, 180, 260, 270, 280, 390 buffer mechanism
61, 71, 81 recess
62, 72, 82, 392 back plate
64,74,84,164,174,184,264,274,284,394 cushioning material
68, 78, 88, 368, 378 Adjusting screw
F1, F2, G1, G2 Moving direction
