JP4068698B2

JP4068698B2 - Universal shaft coupling

Info

Publication number: JP4068698B2
Application number: JP29122597A
Authority: JP
Inventors: 正典望月
Original assignee: ISEL Co Ltd
Current assignee: ISEL Co Ltd
Priority date: 1997-10-23
Filing date: 1997-10-23
Publication date: 2008-03-26
Anticipated expiration: 2017-10-23
Also published as: JPH11125265A

Description

【０００１】
【発明の属する技術分野】
この発明は、自在軸継手に関し、特に、第１継手主体と第２継手主体とが板バネ中間体によって締結される自在軸継手に関する。
【０００２】
【従来の技術】
図７は、従来の自在軸継手を示した図である。図７に示される自在軸継手は、回転入力又は出力側の軸(101a)，軸(101b)を締結するための第１継手主体(103a)と第２継手主体(103b)との周縁に、板ばね中間体(105) のそれぞれ一対の第１延長片(109) ，第２延長片(111) を固定したものである。
【０００３】
板ばね中間体(105) は、軸線に略直角な平面となる板状部(107) と、これの周縁の対称位置から第１継手主体(103a)側に延びる一対の第１延長片(109) と、第２継手主体(103b)側に延びる一対の第２延長片(111) とから構成される。そして、一対の第１延長片(109) と一対の第２延長片(111) とは、軸線を中心にして相互に略９０度ずれている。
【０００４】
第１延長片(109) の先端部は、第１継手主体(103a)のフランジ(113a)の周縁に設けられた取付け平面にネジ止めされている。同様に、第２延長片(111) の先端部は、第２継手主体(103b)のフランジ(113b)の周縁に設けられた取付け平面にネジ止めされている。
さらに、フランジ(113a)の周縁に形成された一対のリブ(115a)の端縁部により構成された側壁部(119a)には、第１延長片(109) の先端側両側辺から突出する一対の矩形状の突出片(117a)が密に嵌入している。同様に、フランジ(113b)の周縁に形成された一対のリブ(115b)の端縁部により構成された側壁部(119b)には、第２延長片(111) の先端側両側辺から突出する一対の矩形状の突出片(117b)が密に嵌入している。
【０００５】
このような自在軸継手では、板状部(107) 及び第１継手主体(103a)，第２継手主体(103b)が撓むことが可能な結果、第１継手主体(103a)の軸線と第２継手主体(103b)の軸線が段違いになった状態（いわゆる偏心）、第１継手主体(103a)の軸線と第２継手主体(103b)の軸線が交差する状態（いわゆる偏角）が生じても、伝動可能であり、伝達トルクを出力側から入力側に伝えることができる。また、トルク伝達状態では、各延長片には、延長片を取付け平面に沿って摺動させる力が作用するものの、延長片の先端が各側壁部(119a)，(119b)に対接し、突出片(117a)，(117b)がリブ(115a)，(115b)間に密嵌しているので、作用力が伝導されてトルク伝達が行われる。
【０００６】
【発明が解決しようとする課題】
しかしながら、従来の自在軸継手では、薄肉の弾性金属板から構成される第１延長片(109) 及び第２延長片(111) の取付け先端部のみが第１継手主体(103a)，第２継手主体(103b)に接触し、その接触部分、具体的には突出片が前述の作用力を直接受けるため、例えば衝突が生じるほどの何らかの原因で過負荷が加わって突出片が撓んで変形してしまう場合があった。
【０００７】
ゆえに、本発明は、過負荷に耐え得る自在軸継手を提供することを課題とする。
【００１０】
【課題を解決するための手段】
請求項１の発明は、第１継手主体と、第２継手主体と、第１継手主体と第２継手主体とを連結させる板バネ中間体とを備えた自在軸継手であって、板バネ中間体が、軸線に略直角な平面となる板状部と、板状部の周縁の対称位置から第１継手主体側に延びる一対の第１延長片と、軸線を中心に一対の第１延長片に対して板状部の周方向に略９０度ずれた周縁の他の対称位置から第２継手主体側に延びる一対の第２延長片とを備え、第１継手主体には、側部に各第１延長片を固定するための一対の第１凹み部が形成されており、第２継手主体には、側部に各第２延長片を固定するための一対の第２凹み部が形成されており、各第１延長片の両側辺の少なくとも一方の所定部分と各対応の第１凹み部の側面との間に介在する第１介在部材と、各第２延長片の両側辺の少なくとも一方の所定部分と各対応の第２凹み部の側面との間に介在する第２介在部材とを備えたことを特徴としている。
【００１１】
このような発明によって、何らかの原因で過負荷が加わっても、第１延長片の両側辺の少なくとも一方の所定部分と各対応の第１凹み部の側面との間に第１介在部材が介在し、第２延長片の両側辺の少なくとも一方の所定部分と各対応の第２凹み部の側面との間に第２介在部材が介在して、過負荷を介在部材で受けることができる。
【００１２】
請求項２の発明は、請求項１の発明において、過負荷が加わった場合に第１介在部材が各対応の第１凹み部の側面に接触するように、第１介在部材と各対応の第１凹み部の側面との間には隙間が設けられ、過負荷が加わった場合に第２介在部材が各対応の第２凹み部の側面に接触するように、第２介在部材と各対応の第２凹み部の側面との間には隙間が設けられる、ことを特徴としている。
【００１３】
請求項１の発明において、通常の回転状態で介在部材と各対応の凹み部の側面とが接触していたとしても、樹脂のような硬度の小さな介在部材であれば、各対応の凹み部の側面を摺動しても傷等がつかないが、請求項２の発明によれば、通常の回転状態では、介在部材と各対応の凹み部の側面との間には隙間が設けられているため、通常回転状態で接触による弊害が生じる可能性を確実に抑えることができる。
【００１４】
請求項３の発明は、請求項１又は２の発明において、各第１延長片の両側辺の所定部分及び各第２延長片の両側辺の所定部分の位置が、板状部側である、ことを特徴としている。
このような発明によって、過負荷を効果的に抑える位置である板状部側の所定部分又はその所定部分に対応する介在部材が、過負荷が加わった場合に各凹み部の側面に接触して全体として過負荷を効果的に抑えるような受け方となる。
【００１７】
【発明の効果】
請求項１の発明は、何らかの原因で過負荷が加わっても、第１延長片の両側辺の少なくとも一方の所定部分が対応の第１凹み部の側面に直接接触せず、第１介在部材が対応の第１凹み部の側面に接触し、第２延長片の両側辺の少なくとも一方の所定部分が対応の第２凹み部の側面に直接接触せず、第２介在部材が対応の第２凹み部の側面に接触して、過負荷を介在部材で受けることができるので、固定された部分のみで過負荷を受ける場合に比べて延長片の受ける過負荷を抑えることができる。従って、従来のような過負荷が加わって先端部が変形してしまうことが生じにくく、過負荷に耐え得る自在軸継手が得られる。特に、介在部材として樹脂のような硬度の小さなものを用いることができ、各延長片と凹み部との過負荷時の接触に比べて衝撃を吸収するような柔らかな衝突の接触状態で済ますことができる。従って、その分だけ、軸継手の受ける過負荷が小さくなり、より過負荷に耐え得る自在軸継手が得られる。
【００１８】
ここで、請求項１の発明において、通常の回転状態で介在部材と各対応の凹み部の側面が接触していたとしても、介在部材として硬度の小さなものを用いることができるため、傷がつかないような摺動も可能である。これに対し、請求項２の発明は、通常の回転状態では、介在部材と各対応の凹み部の側面とが接触しないように隙間を設けており、傷がつくような破損、損傷が生じることをより確実に防ぐことができる。
【００１９】
請求項３の発明は、過負荷を効果的に抑える位置である板状部側の所定部分又は板状部側の一部に装着された介在部材が、過負荷が加わった場合に各凹み部に接触して全体として過負荷を抑えることができ、請求項１又は２のいずれかの発明に比べて、より過負荷に耐え得る自在軸継手を得ることができる。
【００２０】
【発明の実施の形態】
図１は、本発明の実施の形態に係る自在軸継手を示した一部破断させた図であり、図２は、図１の板バネ中間体を示した斜視図であり、図３は、図１のＡ部分の拡大図であり、図４は、図１の介在部材の斜視図であり、図５は、図１のＶ−Ｖライン拡大端面図である。
【００２１】
図１を参照して、自在軸継手(201) は、回転を出力する側の軸(203a)又は軸(203b)の回転を入力側の軸(203b)又は軸(203a)に伝える継手であり、第１継手主体(205a)と、第２継手主体(205b)と、板バネ中間体(207) と、介在部材(209) とを備える。
第１継手主体(205a)及び第２継手主体(205b)について説明する。第１継手主体(205a)及び第２継手主体(205b)は、それぞれ全体としてはリング状をなしており、中心部には入力軸又は出力軸となる軸(203a)，軸(203b)を嵌入するための軸孔部(211) が形成されて貫通している。また、第１継手主体(205a)の外周面には、後述の一対の第１延長片(305a)が嵌め込まれる第１凹み部(215a)が対応して一対形成されており、第２継手主体(205b)の外周面には、後述の一対の第２延長片(305b)が嵌め込まれる第２凹み部(215b)が対応して一対形成されている。第１凹み部(215a)と同様の形状をした第２凹み部(215b)は、板バネ中間体(207) の第２延長片(305b)の先端部が取付けられる取付け平面(217) と、後述の板状部(303) 側に向かって深くなるように傾斜した傾斜部(219) とで底面が形成されている。また、第１凹み部(215a)及び第２凹み部(215b)の幅は、板状部(303) 側の傾斜部(219) に対応する部分が幅Ｌ１であり、取付け平面(217) に対応する部分が幅Ｌ２であり、Ｌ２はＬ１よりも大きく設定されている。
【００２２】
次に、図２を参照して板バネ中間体(207) について説明する。板バネ中間体(207) は、中心部に孔(301) が設けられているものの、軸線に略直角な平面となる板状部(303) と、板状部(303) の周縁の対称位置から第１継手主体(205a)側に延びる一対の第１延長片(305a)と、軸線を中心に一対の第１延長片(305a)に対して板状部(303) の周方向に略９０度ずれた周縁の他の対称位置から第２継手主体(205b)側に延びる一対の第２延長片(305b)とを備えている。より具体的には、板状部(303) は、外周が八角形をなしており、対向する辺から第１延長片(305a)が一対延び、第１延長片(305a)が延びた一対の辺から２つずらした対向する辺から第２延長片(305b)が一対延びている。
【００２３】
第１延長片(305a)及び第２延長片(305b)の板状部(303) 側は、共に幅がＬ３であり、前述の第１凹み部(215a)及び第２凹み部(215b)の幅Ｌ１より小さく設定されている。これに対し、第１延長片(305a)及び第２延長片(305b)の先端部は、前述の第１凹み部(215a)及び第２凹み部(215b)の幅Ｌ２に等しく設定されて、第１延長片(305a)及び第２延長片(305b)の先端部両側辺から延びた突出部(307) が第１継手主体(205a)及び第２継手主体(205b)に嵌入するようになっている。
【００２４】
なお、突出部(307) は、第１凹み部(215a)及び第２凹み部(215b)の取付け平面(217) に対してくい込むようにへの字状をなして突出しており、挿入の際の挿入方向とは逆方向に折れにくいような工夫がなされている。
また、各第１延長片(305a)，第２延長片(305b)の先端部には、ネジ孔(309) が形成されている。
【００２５】
図３を参照して図２の板バネ中間体(207) のさらに構成を説明すると共に、板状部(303) と第１延長片(305a)との接続部分及び板状部(303) と第２延長片(305b)との接続部分について説明する。
板バネ中間体(207) は、それぞれが薄い板バネ(401a)〜(401d)が積層された構成をしており、板状部(303) の部分、第１延長片(305a)の部分、及び第２延長片(305b)の部分自体は接触するように重なっているが、板状部(303) と第２延長片(305b)等との接続部分には隙間があくように重ねられている。即ち、板バネ中間体(207) の曲がり部である接続部分は円弧状で、その円弧状接続部(403a)，(403b)，(403c)，(403d)が隙間をあけつつ重なっている。
【００２６】
具体的には、板バネ(401a)の円弧状接続部(403a)の内面(405) と板バネ(401b)の円弧状接続部(403b)の外面(407) とは接触しておらず隙間(409) が形成されている。同様に、板バネ(401b)の円弧状接続部(403b)の内面(405) と板バネ(401c)の円弧状接続部(403c)の外面(407) とも接触しておらず隙間(409) が形成されており、板バネ(401c)の円弧状接続部(403c)の内面(405) と板バネ(401d)の円弧状接続部(403d)の外面(407) とも接触しておらず隙間(409) が形成されている。
【００２７】
次に、図１の介在部材(209) について図４及び図５を用いて説明する。介在部材(209) は、プラスチック製のスライドであり、直方体の内部がくり抜かれて孔部(501) が形成されたリング状をなしたものである。孔部(501) に板バネ中間体(207) の第１延長片(305a)及び第２延長片(305b)の板状部(303) 側が係合して介在部材(209) が装着されるため、孔部幅がＬ３に設定されている。これに対し、全体の幅は、前述の第１凹み部(215a)の幅及び第２凹み部(215b)の幅であるＬ１に設定されている。
【００２８】
また、介在部材(209) には、リングを分断するような切れ目(503) が形成されている。このような切れ目(503) が形成されているのは、第１延長片(305a)及び第２延長片(305b)の先端部の幅がＬ３より大きなＬ２に設定されているため、先端部側から差し込むことが難しく、切れ目(503) 部分で端部を両側に開いて装着部に容易に装着するためである。
【００２９】
このような介在部材(209) がそれぞれの第１延長片(305a)及び第２延長片(305b)に装着された板バネ中間体(207) は、図１に示すように、第１延長片(305a)及び第２延長片(305b)の先端部が取付けネジ(221) によって締結されて第１継手主体(205a)及び第２継手主体(205b)と接続し、板バネ中間体(207) が接続された第１継手主体(205a)及び第２継手主体(205b)は締付けネジ(213) によって軸(203a)及び軸(203b)に締結されて接続する。接続状態においては、図５に示すように、介在部材(209) の接触面(505a)及び接触面(505b)が第１凹み部(215a)等の側壁に摺動可能な状態で接触している。
【００３０】
以上のように、板バネ中間体(207) の第１延長片(305a)及び第２延長片(305b)の両側辺の板状部(303) 側の一部は、第１継手主体(205a)の対応の各第１凹み部(215a)の側面及び第２継手主体(205b)の対応の各第２凹み部(215b)の側面に直接接触せず、介在部材(209) が介在するようになっている。このように介在部材(209) を介在させたことで、何らかの原因で過負荷が加わっても、衝撃が和らぎ、先端側の突出部(307) 及び介在部材(209) の装着部（板状部(303) 側の一部）に加わる過負荷を小さくでき、突出部(307) が変形したりせず耐久性を向させて、固定部である突出部(307) のみで過負荷を受ける場合に比べて過負荷に耐え得る自在軸継手が得られる。
【００３１】
ところで、過負荷の場合のみならず、通常の回転伝達状態でも、介在部材(209) の回転側及び逆回転側が各対応の凹み部(215a)(215b)の側面に接触して摺動するが、介在部材(209) は、凹み部(215a)(215b)の硬度よりも小さなものとしているので、延長片(305a)(305b)と硬度の大きな凹み部(215a)(215b)とが接触しながらずれて傷がつくような破損、損傷が生じることもない。
【００３２】
但し、通常の回転伝達状態では、介在部材(209) が各対応の凹み部(215a)(215b)の側面に接触しないように、微小の隙間を設けておき、過負荷が加わった場合にのみ接触するようにしておけば、回転伝達時の破損、損傷を確実に防止できるうえに、過負荷に耐え得る自在軸継手が得られる。
【００３３】
なお、図６に示すように、継手主体の他の例として、リングの形を分断するようなすり割りを形成し、ボルトで両端部を固定するものでもよい。さらに、介在部材(209) を装着させる観点からは、板バネが複数積層された板バネ中間体(207) である必要はない。仮に、積層させたとしても、接続部で隙間をあける必要もない。
【００３４】
また、延長片が接続する板状部には、孔が形成されている必要もない。
さらに、図４に示すように介在部材には切り目を入れたが、延長片の先端側が小さく又は同じ大きさであれば切れ目を入れる必要もない。
さらに、図４の介在部材では、切れ目の部分の端部どうしを接触させたが端部どうしが離れて隙間があいたものであってもよい。
【００３５】
さらに、一の延長片に対して一の介在部材である必要はなく、コの字状の二つの介在部材を延長片の両側辺に嵌め込むようなものであってもよい。ただし、コの字状の介在部材を延長片の両側辺から嵌め込む場合には、本来の装着位置から延長片に沿ってスライドしてしまうような装着度合の低下が生じないような工夫が必要であり、図４の場合でさえ小さな介在部材をさらに二つにして小さくなった介在部材を装着する手間がかかる欠点がある。
【００３６】
さらに、二つのコの字状の介在部材を延長片の両側辺に嵌め込まず一方のみ（例えば回転時又は停止時のみの過負荷を考慮して）を取付けることができるが、回転時及び停止時いずれの場合の過負荷にも対処し、さらに、例えば回転時の場合も回転側及び逆回転側の両側辺に介在部材を介在させた方が効果が確実に得られるので、図４のように回転側及び逆回転側の両側辺にも介在部材を介在させるものが好ましい。
【００３７】
さらに、介在部材を介在させる意味からは、本来は、前述のように介在部材の硬度が継手主体の硬度よりも小さなものでなければならないが、継手主体としては金属製、単なる樹脂製、ガラス又は炭素繊維入り樹脂製等が考えられ、それぞれの製品の材質よりも硬度の低い介在部材を用いることが好ましいものの、必ずしも硬度が小さい必要はない。
【００３８】
さらに、特開平８−２７７８４６号公報で示されるように、突出部(307) を山形にし、その山形に嵌合するような山形を第１継手主体(205a)及び第２継手主体(205b)に設けて、さらに突出部(307) の変形を抑える工夫を行ってもよい。
さらに、延長片の継手主体への取付けには、ネジの締結という手段を用いたが、特開平８−２７７８４６号公報で示されるように、カシメ止めによって固定したものであってもよい。このカシメ止めの方法としては、第１継手主体(205a)を樹脂で成形し、取付平面に突出した軸部を図２のネジ孔(309) に嵌入し、その軸を潰すような場合の他、板バネ中間体(207) の突出部(307) を山形にし、その山形に嵌合するような山形を第１継手主体(205a)及び第２継手主体(205b)に設け、山形を上から押し潰すようにする場合であってもよい。
【００３９】
さらに、突出部(307) の突出方向は、第１継手主体(205a)及び第２継手主体(205b)にくい込むような方向である必要はなく、取付け平面(217) に対して平行な方向に延びる場合の他、逆に第１継手主体(205a)及び第２継手主体(205b)から離れる方向に突出したものであってもよい。特に、第１継手主体(205a)及び第２継手主体(205b)から離れるように突出したものの場合は、係合最終位置で圧接し、取り外す際には余分な力が要らずに簡単な取り外しができるという効果がある。
【００４０】
さらに、介在部材(209) の取付位置は、過負荷を受けるのに最も効果的な第１延長片(305a)及び第２延長片(305b)の板状部(303) 側にしたが、必ずしもこちら側に設ける必要はない。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る自在軸継手を示した図であって、一部を破断させた図である。
【図２】図１の板バネ中間体を示した斜視図である。
【図３】図１のＡで囲まれた部分の拡大図である。
【図４】図１の介在部材の斜視図である。
【図５】図１のＶ−Ｖライン拡大断面図である。
【図６】継手主体の他の例を示した図である。
【図７】従来の自在軸継手を示した図である。
【符号の説明】
(201) (601) ・・・自在軸継手
(205a)・・・第１継手主体
(205b)・・・第２継手主体
(207) (603) ・・・板バネ中間体
(209) ・・・介在部材
(215a)・・・第１凹み部
(215b)・・・第２凹み部
(303) ・・・板状部
(305a)(605a)・・・第１延長片
(305b)(605b)・・・第２延長片
(503) ・・・切れ目[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a universal shaft joint, and more particularly to a universal shaft joint in which a first joint main body and a second joint main body are fastened by a leaf spring intermediate body.
[0002]
[Prior art]
FIG. 7 is a view showing a conventional universal shaft joint. The universal shaft joint shown in FIG. 7 is provided at the periphery of the first joint main body (103a) and the second joint main body (103b) for fastening the shaft (101a) and the shaft (101b) on the rotational input or output side. The pair of first extension pieces (109) and second extension pieces (111) of the leaf spring intermediate body (105) are fixed.
[0003]
The leaf spring intermediate body (105) includes a plate-like portion (107) that is a plane substantially perpendicular to the axis, and a pair of first extension pieces (109) extending from the symmetrical position of the peripheral edge to the first joint main body (103a) side. ) And a pair of second extension pieces (111) extending toward the second joint main body (103b) side. The pair of first extension pieces (109) and the pair of second extension pieces (111) are offset from each other by approximately 90 degrees about the axis.
[0004]
The tip of the first extension piece (109) is screwed to a mounting plane provided on the periphery of the flange (113a) of the first joint main body (103a). Similarly, the tip of the second extension piece (111) is screwed to a mounting plane provided on the periphery of the flange (113b) of the second joint main body (103b).
Further, the side wall portion (119a) formed by the edge portions of the pair of ribs (115a) formed on the peripheral edge of the flange (113a) has a pair protruding from both sides on the front end side of the first extension piece (109). The rectangular protruding piece (117a) is closely fitted. Similarly, the side wall portion (119b) formed by the edge portions of the pair of ribs (115b) formed on the peripheral edge of the flange (113b) protrudes from both sides on the front end side of the second extension piece (111). A pair of rectangular protruding pieces (117b) are closely fitted.
[0005]
In such a universal shaft joint, the plate-shaped portion (107), the first joint main body (103a), and the second joint main body (103b) can be bent. As a result, the axis of the first joint main body (103a) A state where the axis of the two joint main body (103b) is stepped (so-called eccentricity), a state where the axis of the first joint main body (103a) intersects the axis of the second joint main body (103b) (so-called declination) occurs. The transmission torque can be transmitted from the output side to the input side. In the torque transmission state, each extension piece is subjected to a force that slides the extension piece along the mounting plane, but the tip of the extension piece comes into contact with each side wall portion (119a), (119b) and protrudes. Since the pieces (117a) and (117b) are closely fitted between the ribs (115a) and (115b), the acting force is conducted and torque transmission is performed.
[0006]
[Problems to be solved by the invention]
However, in the conventional universal shaft joint, only the mounting tips of the first extension piece (109) and the second extension piece (111) made of thin elastic metal plates are the first joint main body (103a) and the second joint. The main part (103b) is in contact, and the contact part, specifically the protruding piece, directly receives the aforementioned acting force.For example, the protruding piece bends and deforms due to an overload due to some cause such as a collision. There was a case.
[0007]
Therefore, an object of the present invention is to provide a universal shaft joint that can withstand overload.
[0010]
[Means for Solving the Problems]
The invention according to claim 1 is a universal shaft joint comprising a first joint main body, a second joint main body, and a leaf spring intermediate body for connecting the first joint main body and the second joint main body, A plate-like portion whose body is a plane substantially perpendicular to the axis, a pair of first extension pieces extending from the symmetrical position of the periphery of the plate-like portion to the first joint main body side, and a pair of first extension pieces about the axis And a pair of second extension pieces extending toward the second joint main body side from the other symmetrical positions of the peripheral edge shifted by about 90 degrees in the circumferential direction of the plate-shaped part, and the first joint main body includes A pair of first dents for fixing the first extension piece is formed, and a pair of second dents for fixing each second extension piece is formed on the side of the second joint main body. A first interposed member interposed between at least one predetermined portion on both sides of each first extension piece and a side surface of each corresponding first recess, and each first It is characterized by comprising at least one of the predetermined portion of both sides of the extension piece and the second intermediate member interposed between the side surface of the second recess of the corresponding.
[0011]
According to such an invention, even if an overload is applied for some reason, the first interposed member is interposed between at least one predetermined portion on both sides of the first extension piece and the side surface of each corresponding first recess. The second interposed member is interposed between at least one predetermined portion on both sides of the second extension piece and the side surface of each corresponding second recessed portion, and an overload can be received by the interposed member.
[0012]
According to a second aspect of the present invention, in the first aspect of the present invention, when an overload is applied, the first interposition member and the corresponding first interposition member are arranged such that the first interposition member contacts the side surface of the corresponding first recess. A gap is provided between the side surface of the first recess and the second interposed member contacts each side of the corresponding second recess so that the second interposed member contacts the side of each corresponding second recess when an overload is applied. It is characterized in that a gap is provided between the side surface of the second recess.
[0013]
In the first aspect of the present invention, even if the interposition member and the corresponding side surface of the corresponding recess are in contact with each other in a normal rotation state, if the interposition member has a low hardness such as a resin, Even if the side surface is slid, scratches or the like are not caused. However, according to the invention of claim 2, a gap is provided between the interposed member and the side surface of each corresponding recess in a normal rotation state. Therefore, it is possible to reliably suppress the possibility of adverse effects caused by contact in the normal rotation state.
[0014]
The invention of claim 3 is the invention of claim 1 or 2 , wherein the positions of the predetermined portions on both sides of each first extension piece and the predetermined portions on both sides of each second extension piece are on the plate-like portion side. It is characterized by that.
By such an invention, when the overload is applied, the predetermined part on the plate-like part side where the overload is effectively suppressed or the intervening member corresponding to the predetermined part comes into contact with the side surface of each recess. Overall, it will be a way to effectively suppress overload.
[0017]
【The invention's effect】
According to the first aspect of the present invention, even if an overload is applied for some reason, at least one predetermined portion of both sides of the first extension piece does not directly contact the side surface of the corresponding first recess, and the first interposed member The side surface of the corresponding first dent portion is in contact, and at least one predetermined portion of both sides of the second extension piece does not directly contact the side surface of the corresponding second dent portion, and the second interposed member is in the corresponding second dent portion. Since the overload can be received by the interposition member in contact with the side surface of the portion, the overload received by the extension piece can be suppressed as compared with the case where the overload is received only by the fixed portion. Therefore, it is difficult for the tip portion to be deformed due to an overload as in the conventional case, and a universal shaft joint that can withstand the overload is obtained. In particular, it is possible to use a material with a low hardness such as resin as the interposition member, and it should be in a soft collision contact state that absorbs shock compared to the contact between each extension piece and the recess when overloaded. Can do. Accordingly, by that amount, the overload experienced by the shaft coupling is reduced, universal joint is obtained good Ri withstand overloading.
[0018]
Here, in the invention of claim 1 , even if the interposition member and the side surface of each corresponding recess are in contact with each other in a normal rotation state, the interposition member having a low hardness can be used. Sliding is possible. On the other hand, in the invention according to claim 2 , in the normal rotation state, a gap is provided so that the interposition member and the side surface of each corresponding dent portion do not come into contact with each other . Can be prevented more reliably.
[0019]
According to the invention of claim 3 , the interposition member attached to a predetermined part on the plate-like part side or a part on the plate-like part side which is a position for effectively suppressing the overload is provided with each depression when an overload is applied. As a result, the overload can be suppressed as a whole, and a universal shaft joint that can withstand the overload can be obtained as compared with the invention of any one of claims 1 and 2 .
[0020]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a partially broken view showing a universal shaft joint according to an embodiment of the present invention, FIG. 2 is a perspective view showing a leaf spring intermediate body of FIG. 1, and FIG. FIG. 4 is an enlarged view of a portion A in FIG. 1, FIG. 4 is a perspective view of the interposed member in FIG. 1, and FIG. 5 is an enlarged end view taken along line VV in FIG.
[0021]
Referring to FIG. 1, the universal shaft joint (201) is a joint that transmits the rotation of the shaft (203a) or the shaft (203b) on the rotation output side to the shaft (203b) or the shaft (203a) on the input side. A first joint main body (205a), a second joint main body (205b), a leaf spring intermediate body (207), and an interposition member (209).
The first joint main body (205a) and the second joint main body (205b) will be described. Each of the first joint main body (205a) and the second joint main body (205b) has a ring shape as a whole, and the shaft (203a) and shaft (203b) serving as an input shaft or an output shaft are inserted into the center portion. A shaft hole portion (211) is formed and penetrated. In addition, a pair of first recesses (215a) into which a pair of first extension pieces (305a) to be described later are fitted are formed on the outer peripheral surface of the first joint main body (205a). On the outer peripheral surface of (205b), a pair of second recesses (215b) into which a pair of second extension pieces (305b) to be described later are fitted are formed. The second dent (215b) having the same shape as the first dent (215a) includes an attachment plane (217) to which the tip of the second extension piece (305b) of the leaf spring intermediate (207) is attached, A bottom surface is formed by an inclined portion (219) inclined so as to become deeper toward a plate-like portion (303) described later. Further, the width of the first recess (215a) and the second recess (215b) is such that the portion corresponding to the inclined portion (219) on the plate-like portion (303) side is the width L1, and the mounting plane (217) The corresponding part is the width L2, and L2 is set larger than L1.
[0022]
Next, the leaf spring intermediate (207) will be described with reference to FIG. Although the leaf spring intermediate (207) has a hole (301) at the center, the plate-like portion (303) that is a plane substantially perpendicular to the axis and the peripheral position of the plate-like portion (303) are symmetrical. A pair of first extension pieces (305a) extending from the first joint main body (205a) to the side of the first joint main body (205a) and the pair of first extension pieces (305a) about the axis in the circumferential direction of the plate-like portion (303) And a pair of second extension pieces (305b) extending toward the second joint main body (205b) from other symmetrical positions of the peripheral edge shifted in degree. More specifically, the plate-like portion (303) has an octagonal outer periphery, a pair of first extension pieces (305a) extending from opposite sides, and a pair of first extension pieces (305a) extending. A pair of second extension pieces (305b) extend from opposing sides shifted by two from the sides.
[0023]
The plate-like portion (303) side of the first extension piece (305a) and the second extension piece (305b) has a width of L3, and the first depression portion (215a) and the second depression portion (215b) have the same width. It is set smaller than the width L1. On the other hand, the front end portions of the first extension piece (305a) and the second extension piece (305b) are set equal to the width L2 of the first recess portion (215a) and the second recess portion (215b). Protrusions (307) extending from both side edges of the first extension piece (305a) and the second extension piece (305b) are inserted into the first joint main body (205a) and the second joint main body (205b). ing.
[0024]
The protrusion (307) protrudes in a U-shape so as to be inserted into the mounting plane (217) of the first recess (215a) and the second recess (215b). The device has been devised so that it does not easily break in the direction opposite to the insertion direction.
In addition, screw holes (309) are formed at the distal ends of the first extension pieces (305a) and the second extension pieces (305b).
[0025]
With reference to FIG. 3, the structure of the leaf spring intermediate body (207) of FIG. 2 will be described, and the connecting portion between the plate-like portion (303) and the first extension piece (305a) and the plate-like portion (303) A connection portion with the second extension piece (305b) will be described.
The leaf spring intermediate body (207) has a structure in which thin leaf springs (401a) to (401d) are laminated, and includes a plate-like portion (303) portion, a first extension piece (305a) portion, And the part of the second extension piece (305b) is overlapped so as to be in contact with each other, but the connecting part between the plate-like part (303) and the second extension piece (305b) is overlapped with a gap. Yes. That is, the connection part which is a bent part of the leaf spring intermediate body (207) has an arc shape, and the arc connection parts (403a), (403b), (403c) and (403d) overlap with each other with a gap.
[0026]
Specifically, the inner surface (405) of the arcuate connection (403a) of the leaf spring (401a) and the outer surface (407) of the arcuate connection (403b) of the leaf spring (401b) are not in contact with each other. (409) is formed. Similarly, neither the inner surface (405) of the arc-shaped connection portion (403b) of the leaf spring (401b) nor the outer surface (407) of the arc-shaped connection portion (403c) of the leaf spring (401c) is in contact with the gap (409). Is not in contact with the inner surface (405) of the arc connection (403c) of the leaf spring (401c) and the outer surface (407) of the arc connection (403d) of the leaf spring (401d). (409) is formed.
[0027]
Next, the interposition member (209) in FIG. 1 will be described with reference to FIGS. The interposition member (209) is a plastic slide and has a ring shape in which the inside of the rectangular parallelepiped is cut out to form a hole (501). The plate member (303) side of the first extension piece (305a) and the second extension piece (305b) of the leaf spring intermediate body (207) is engaged with the hole portion (501) to mount the interposition member (209). Therefore, the hole width is set to L3. On the other hand, the overall width is set to L1 which is the width of the first recess (215a) and the width of the second recess (215b).
[0028]
The interposition member (209) is formed with a cut (503) that divides the ring. The reason why such a cut (503) is formed is that the width of the tip of the first extension piece (305a) and the second extension piece (305b) is set to L2 larger than L3. This is because it is difficult to insert it into the mounting portion, and the end portion is opened on both sides at the cut (503) portion, so that the mounting portion can be easily attached.
[0029]
As shown in FIG. 1, the leaf spring intermediate body (207) in which such an interposition member (209) is mounted on the first extension piece (305a) and the second extension piece (305b) is formed into the first extension piece. (305a) and the distal end of the second extension piece (305b) are fastened by mounting screws (221) to be connected to the first joint main body (205a) and the second joint main body (205b), and the leaf spring intermediate body (207) The first joint main body (205a) and the second joint main body (205b) connected to each other are fastened and connected to the shaft (203a) and the shaft (203b) by the tightening screw (213). In the connected state, as shown in FIG. 5, the contact surface (505a) and the contact surface (505b) of the interposed member (209) are in contact with the side wall of the first recess (215a) in a slidable state. Yes.
[0030]
As described above, a part of the plate-like portion (303) side of both sides of the first extension piece (305a) and the second extension piece (305b) of the leaf spring intermediate body (207) is the first joint main body (205a ) So that the interposition member (209) intervenes without directly contacting the side surface of each corresponding first dent (215a) and the side surface of each corresponding second dent (215b) of the second joint main body (205b). It has become. By interposing the interposition member (209) in this way, even if an overload is applied for some reason, the impact is reduced, and the protruding portion (307) on the tip side and the mounting portion (plate-like portion) of the interposition member (209) (Part on the (303) side) can be reduced, and the protrusion (307) will not be deformed and the durability will be improved, so that only the fixed protrusion (307) will be overloaded. As a result, a universal shaft joint capable of withstanding overload can be obtained.
[0031]
By the way, not only in the case of an overload, but also in a normal rotation transmission state, the rotation side and the reverse rotation side of the interposed member (209) are in contact with the side surfaces of the corresponding recesses (215a) (215b) and slide. Since the interposition member (209) is smaller in hardness than the recesses (215a) and (215b), the extension pieces (305a) and (305b) are in contact with the recesses (215a) and (215b) having high hardness. However, there will be no breakage or damage that would cause damage.
[0032]
However, in a normal rotation transmission state, a minute gap is provided so that the interposition member (209) does not contact the side surface of each corresponding recess (215a) (215b), and only when an overload is applied. If contact is made, it is possible to reliably prevent breakage and damage during rotation transmission, and to obtain a universal shaft joint that can withstand overload .
[0033]
In addition, as shown in FIG. 6 , as another example of the joint main body, a slit that divides the shape of the ring may be formed, and both ends may be fixed with bolts. Further, from the viewpoint of mounting the interposition member (209), it is not necessary to be a leaf spring intermediate body (207) in which a plurality of leaf springs are stacked. Even if they are stacked, there is no need to open a gap at the connecting portion.
[0034]
Moreover, it is not necessary to form a hole in the plate-like portion to which the extension piece is connected.
Furthermore, as shown in FIG. 4, the intervening member is cut, but if the distal end side of the extension piece is small or the same size, there is no need to make a cut.
Furthermore, in the interposition member of FIG. 4, the end portions of the cut portion are brought into contact with each other, but the end portions may be separated to have a gap.
[0035]
Further, it is not necessary to be one interposed member for one extended piece, and two U-shaped interposed members may be fitted on both sides of the extended piece. However, when the U-shaped interposition member is fitted from both sides of the extension piece, it is necessary to devise a technique that does not cause a reduction in the degree of attachment that slides along the extension piece from the original attachment position. Even in the case of FIG. 4, there is a drawback that it takes time and effort to mount a small interposed member by making two smaller interposed members.
[0036]
Furthermore, it is possible to attach only one of the two U-shaped interposition members without fitting them on both sides of the extension piece (for example, considering overload only at the time of rotation or stop). In order to cope with overload in any case, and further, for example, in the case of rotation, it is more reliable to intervene between both sides of the rotation side and the reverse rotation side, so the effect can be obtained reliably, as shown in FIG. It is preferable to interpose an intervening member on both sides of the rotation side and the reverse rotation side .
[0037]
Furthermore, from the meaning of interposing the interposition member, originally, the hardness of the interposition member must be smaller than the hardness of the joint main body as described above, but the joint main body is made of metal, simple resin, glass or Although it is possible to use carbon fiber-containing resin and the like, it is preferable to use an interposition member having a lower hardness than the material of each product, but the hardness is not necessarily small .
[0038]
Further, as shown in Japanese Patent Application Laid-Open No. 8-277646, the projecting portion (307) has a chevron shape, and the chevron shape that fits the chevron shape is formed on the first joint main body (205a) and the second joint main body (205b). It is also possible to devise a means for suppressing the deformation of the protrusion (307).
Further, for attaching the extension piece to the joint main body, a means of fastening a screw is used. However, as shown in JP-A-8-277846, it may be fixed by caulking. This caulking stop method is other than the case in which the first joint main body (205a) is molded with resin, the shaft portion protruding from the mounting plane is inserted into the screw hole (309) in FIG. 2, and the shaft is crushed. The projecting portion (307) of the leaf spring intermediate body (207) is formed into a mountain shape, and a mountain shape that fits into the mountain shape is provided in the first joint main body (205a) and the second joint main body (205b). It may be a case of crushing.
[0039]
Further, the projecting direction of the projecting portion (307) does not have to be a direction in which the first joint main body (205a) and the second joint main body (205b) are not easily inserted, and is in a direction parallel to the mounting plane (217). In addition to the case where it extends, it may be one that protrudes in a direction away from the first joint main body (205a) and the second joint main body (205b). In particular, when protruding from the first joint main body (205a) and the second joint main body (205b), they are pressed at the final engagement position and can be easily removed without any extra force when removing. There is an effect that can be done.
[0040]
Furthermore, the mounting position of the interposition member (209) is set to the plate-like portion (303) side of the first extension piece (305a) and the second extension piece (305b) which is most effective for receiving overload. It is not necessary to install on this side.
[Brief description of the drawings]
FIG. 1 is a diagram showing a universal shaft joint according to an embodiment of the present invention, with a part thereof broken.
2 is a perspective view showing a leaf spring intermediate body of FIG. 1. FIG.
FIG. 3 is an enlarged view of a portion surrounded by A in FIG. 1;
4 is a perspective view of the interposition member of FIG. 1. FIG.
FIG. 5 is an enlarged cross-sectional view taken along line VV in FIG. 1;
FIG. 6 is a view showing another example of a joint main body.
FIG. 7 is a view showing a conventional universal shaft joint.
[Explanation of symbols]
(201) (601) ... Universal shaft coupling
(205a) ... 1st joint body
(205b) ... 2nd joint mainly
(207) (603) ・・・ Leaf spring intermediate
(209) ... Intervening member
(215a) ... 1st dent
(215b) ... second recess
(303) ... Plate-shaped part
(305a) (605a) ・・・ First extension piece
(305b) (605b) ・・・ Second extension piece
(503) ・・・ Cut

Claims

A universal shaft joint comprising a first joint main body, a second joint main body, and a leaf spring intermediate body for connecting the first joint main body and the second joint main body,
The leaf spring intermediate body has a plate-like portion that is a plane substantially perpendicular to the axis, a pair of first extension pieces that extend from the symmetrical position of the periphery of the plate-like portion to the first joint main body, and the axis. A pair of second extension pieces extending toward the second joint main body from another symmetrical position of the peripheral edge shifted by approximately 90 degrees in the circumferential direction of the plate-like portion with respect to the pair of first extension pieces,
The first joint main body is formed with a pair of first dent portions for fixing the first extension pieces on the side portions,
The second joint main body is formed with a pair of second recessed portions for fixing the second extension pieces on the side portions,
A first interposition member interposed between at least one predetermined portion on both sides of each first extension piece and a side surface of each corresponding first recess;
A universal shaft coupling comprising: a second interposed member interposed between at least one predetermined portion on both sides of each second extension piece and a side surface of each corresponding second recess.

When the overload is applied, the first interposed member is in contact with the side surfaces of the corresponding first recessed portions, so that the first interposed member is in contact with the side surfaces of the corresponding first recessed portions. There is a gap,
When the overload is applied, the second interposed member is in contact with the side surface of each corresponding second recessed portion so that the second interposed member is in contact with the side surface of each corresponding second recessed portion. The universal shaft joint according to claim 1, wherein a gap is provided.

The universal shaft coupling according to claim 1 or 2, wherein the positions of the predetermined portions on both sides of each first extension piece and the predetermined portions on both sides of each second extension piece are on the plate-like portion side.