JP3760127B2

JP3760127B2 - Robot joint support structure

Info

Publication number: JP3760127B2
Application number: JP2001344440A
Authority: JP
Inventors: 敦夫池口
Original assignee: Hosiden Corp
Current assignee: Hosiden Corp
Priority date: 2001-11-09
Filing date: 2001-11-09
Publication date: 2006-03-29
Anticipated expiration: 2021-11-09
Also published as: JP2003145475A

Description

【０００１】
【発明の属する技術分野】
本発明は、ロボットの関節部支持構造、たとえば動物ロボットの前後の脚などの関節部に採用されるロボットの関節部支持構造に関する。
【０００２】
【従来の技術】
動物ロボットにおいて、たとえば前後の脚を動かせるためには、脚に設けた関節部に回動軸を配備し、その回動軸にモータの回転を伝達させるという手段を採用することができる。この場合、回動軸を軸受で支持する必要がある。そこで、従来は、軸受としてベアリングを採用していた。
【０００３】
【発明が解決しようとする課題】
しかしながら、軸受にベアリングを採用して関節部を形成すると、ベアリングが高価であるためにコスト高になるという問題があるだけでなく、脚を形作る筐体へのベアリングの組込み精度や回動軸などの組込み精度にも高精度が要求されるほか、必要部品の成形や関節部の組立てにも熟練を要するという問題があった。
【０００４】
本発明は以上の問題に鑑みてなされたものであり、回動軸を支持する軸受に安価な筒体を用いることを基本として、軸受や回動軸の組込みにそれほど高い精度が要求されないロボットの関節部支持構造を提供することを目的とする。
【０００５】
また、本発明は、軸受の塵埃からの保護が図られ、併せて、回動軸に回転を伝達するための歯車の取付けやその歯車に対する回動軸の取付け、さらには関節部の組立てを容易に行うことのできるロボットの関節部支持構造を提供することを目的とする。
【０００６】
【課題を解決するための手段】
本発明に係るロボットの関節部支持構造は、２つの部材が回動軸により相対揺動可能に連結され、その回動軸に回転伝達用の歯車が取り付けられている。
【０００７】
そして、上記回動軸に相対摺動回転自在に外嵌合された筒体でなる軸受が、２つの上記部材のうちの一方側部材に具備されてその軸受の高さ寸法よりも長い深さ寸法を有する凹入部の内部に収容保持されていると共に、上記歯車に同心状に具備された環状凸部とその環状凸部の外側に位置する環状の当り面とのうちの上記環状凸部が上記軸受の収容箇所よりも外側で上記凹入部に摺動回転自在に嵌合されて、上記当り面がその凹入部の開口の周囲に具備された環状の受面に摺動回転自在に重ね合わされている。
【０００８】
この構成であれば、筒体でなる軸受が一方側部材の凹入部の内部に収容保持されることによって位置決めされ、そのように位置決めされた軸受によって回動軸が摺動回転自在に支えられる。したがって、軸受に高価なベアリングを用いる必要がなくなる。また、歯車の環状凸部が嵌合されることによって開口が塞がれた凹入部の内部に筒体でなる軸受が収容保持されているので、歯車の環状凸部が凹入部を密閉し、かつ、歯車の当り面が凹入部の開口の周囲の環状の受面に重なり合うことによって凹入部の内部への塵埃の侵入が防止される。そのため、回動軸と軸受との摺動箇所に塵埃が侵入して回動軸の回動動作の円滑性が損なわれるという事態が起こりにくい。
【０００９】
本発明では、上記軸受が上記凹入部に圧入状態で収容保持され、かつ、その軸受の上記高さ寸法よりも、上記環状凸部の端面と上記凹入部の底面との対向間隔寸法が長くなっていることが望ましい。これによれば、歯車の環状凸部の端面と軸受との間に隙間を形成して歯車の環状凸部が軸受と擦れ合わないようにすることが可能であり、そうしておくことによって、歯車の回転が回動軸に円滑に伝達されるようになる。また、軸受を収容保持している凹入部の開口が歯車の環状凸部によって塞がれているので、軸受が回動軸に対して軸方向に位置ずれするような事態が起こったとしても、その軸受が凹入部から離脱してしまうというトラブルは起こり得ず、たとえ軸受が回動軸に対して軸方向に位置ずれしても軸受としての機能が損なわれない。
【００１０】
本発明では、上記軸受と、上記受面及び上記凹入部を有する上記一方側部材と、上記環状凸部及び上記当り面を有する上記歯車とのそれぞれが合成樹脂成形体でなることが望ましい。このように軸受、一方側部材、歯車などを合成樹脂成形体で製作しておくと、それらの部品が安価になり、コストダウンを促進しやすい。
【００１１】
本発明では、上記一方側部材が、互いに結合されて歯車箱を形成する第１及び第２のケースに分割された偏平な筐体でなり、上記軸受を収容保持している上記凹入部が第１及び第２の上記各ケースのそれぞれに具備され、それらの各凹入部に、上記歯車の軸方向両端のそれぞれに同心状に具備された上記環状凸部が摺動回転自在に各別に嵌合されていると共に、上記各凹入部の開口の周囲に具備された上記受面に、上記各環状凸部の外側に位置する上記当り面が摺動回転自在に各別に重ね合わされているという構成を採用することが望ましい。
【００１２】
これによれば、たとえば歯車を配備した第１ケースに対して第２ケースを結合するという手順で偏平な筐体を組み立てることが可能になる。その場合、特に、第１ケースの凹入部に軸受を嵌め込んだ後、その凹入部に歯車の片側の環状凸部を嵌合して片側の当り面をその凹入部の開口の周囲の受面に重ね合わせると、歯車が第１ケースに対して位置決めされるので、その第１ケースに第２ケースを結合する組立て作業を容易に行うことができ、しかも、第１ケースに第２ケースを結合する組立て作業を行う際には、第２ケースの凹入部を歯車の他側の環状凸部に嵌合して他側の当り面にその凹入部の開口の周囲の受面を重ね合わせるということが行われるので、第１ケースに第２ケースを位置合わせする作業が容易になる。
【００１３】
本発明では、第１及び第２のケースのうちの少なくとも一方側に具備されている上記凹入部が、その一方側のケースに設けられた筒部の内部空間によって形成され、上記歯車の軸方向片側面に、その筒部に外嵌合された環状リブが備わっているという構成を採用することが望ましい。これによれば、一方側のケースに歯車を配備するときに、歯車の環状凸部と環状リブとによって形作られた環状の凹所に、凹入部を形成している筒部を嵌め込むという作業を通じて歯車を一方側のケースの適正位置に配備することができる。したがって、一方側のケースに対する歯車の配備を容易に行うことが可能になる。この作用は、上記環状リブが上記筒部の外側に遊嵌合されている、という構成を採用することによっていっそう顕著に発揮される。
【００１４】
本発明では、上記回動軸が、上記凹入部と同心状に２つの上記部材に具備された孔部に貫挿されたまっすぐな軸体でなることが望ましい。
【００１５】
これによれば、２つの部材の孔部に対して回動軸を貫挿することによって、それら２つの部材が連結されると共に、一方側部材に組み込まれている歯車や軸受に回動軸を挿通させることができる。
【００１６】
【発明の実施の形態】
図１は本発明を適用した動物ロボットの概略部分側面図、図２は同ロボットのモジュール１０と前側の脚部１２０とを示した概略側面図、図３は図２のＩＩＩ矢視図である。
【００１７】
図１のように、本発明に係るロボットは、構体１００を有し、それは、胴体１１０に、図示省略した首部や頭部のほか、前後の脚部１２０，１３０が、前後に揺動することができるように取り付けられている。また、それらの脚部１２０，１３０には関節部１２１，１２２，１３１，１３２があり、これらの関節部１２１，１２２，１３１，１３２の作用で、動物の脚と同様の動きが行われるようになっている。なお、このロボットは内蔵した電池を動力源として動作する。
【００１８】
胴体１１０は複数のモジュールを組み合わせることによって形作られていて、図１にはそれらのモジュールの１つを符号１０で示してある。そして、図１又は図２のように、このモジュール１０に軸体２０を介して前側の脚部１２０の付け根側部分を形成している部材である筐体３０が取り付けられている。さらに、この筐体３０に関節部１２１を介して脚部１２０の他の部分を形成している他の部材であるアーム部材１２３が連結され、さらに、このアーム部材１２３に脚先部分を形成している先端部材１２４が関節部１２２を介して連結されている。後側の脚部１３０も前側の脚部１２０とほゞ同じ構成になっている。
【００１９】
上記筐体３０は歯車箱を形成していて、その筐体３０の内部に後述する歯車列が配備されている。また、この筐体３０の外側にカバー３０ａがねじ止めされていて、筐体３０とカバー３０ａとによって囲まれた内部空間に配線基板などの電気制御部品が配備されている。
【００２０】
さらに、図３に見られるように、筐体３０は、モジュール１０側の第１ケース４０と、その第１ケース４０に結合された第２ケース６０とに分割されていると共に、両ケース４０，６０を結合することによって偏平に形作られている。
【００２１】
図４は歯車箱としての筐体３０の内部に配備された歯車列を筐体３０の片側ケースを形成している第２ケース６０と共に示している。同図のように、この歯車列は、モータＭの出力歯車８１と、この出力歯車８１に噛み合わされた複数の中間歯車８２…と、これらの中間歯車８２…を介して上記出力歯車８１の回転が減速して伝達される最終歯車９０とを備えていて、最終歯車９０（以下単に「歯車９０」という）が図２などに示した関節部１２１に組み込まれている。
【００２２】
図５は歯車９０を片側から見た平面図、図６は歯車９０を他側から見た平面図、図７は図５のＶＩＩ−ＶＩＩ線に沿う部分の概略断面図である。
【００２３】
この歯車９０は合成樹脂の一体成形体でなり、略半周部分に欠歯部９１を有していると共に、その欠歯部９１の外周部分と有歯部９２の外周部分とには、歯車９０の軸方向片側又は他側に突き出た環状リブ９３，９４がそれぞれ備わっている。また、歯車９０の中央部には、軸方向他側に突き出た筒状のボス部９５が一体に備わっている。なお、このボス部９５には、径小な円形の孔部９６ａと欠円部を有する径大な孔部９６ｂとが同心に備わっていると共に、このボス部９５の軸方向端面に、円形の環状凸部９７とその環状凸部９７の外側に位置する環状の当り面９８ａとが同心状に備わっている。これに対し、歯車９０の軸方向片側に、上記環状凸部９７と同心に位置する環状凸部９９が備わっている。なお、図示例において、上記環状凸部９９はその周方向等間隔おきの３箇所が一定幅に亘って欠除されている。
【００２４】
上記歯車９０が組み付けられる第１及び第２の各ケース４０，６０も合成樹脂で一体成形されていて、それらの各ケース４０，６０のそれぞれに、内向きに突設された円筒状の筒部４１，６１の内部空間によって形成されてなる凹入部が備わっている。そして、それらの各筒部４１，６１の内部に、筒体でなる軸受７１，７５が圧入状態で収容保持されていると共に、各ケース４０，６０には、筒部４１，６１と同心状に円形孔４２，６２が備わっている。上記各軸受７１，７５も合成樹脂成形体でなる。ここで、軸受７１を内部に収容保持している第１ケース４０の筒部４１の深さ寸法（筒部４１の高さ寸法）は、軸受７１の高さ寸法（軸長）よりも長くなっている。そのため、筒部４１は、その筒部４１の根元位置まで圧入されている軸受７１よりも突き出ている。これと同様に、軸受７５を内部に収容保持している第２ケース６０の筒部６１の深さ寸法（筒部６１の高さ寸法）は、軸受７５の高さ寸法（軸長）よりも長くなっている。そのため、筒部６１は、その筒部６１の根元位置まで圧入されている軸受７５よりも突き出ている。また、上記した筒部４１の深さ寸法は、軸受７１の高さ寸法と上記した歯車９０に設けられている環状凸部９７の高さ寸法とを合わせた寸法よりも少し長くなっている。同様に、上記した筒部６１の深さ寸法は、軸受７５の高さ寸法と上記した歯車９０に設けられている環状凸部９９の高さ寸法とを合わせた寸法よりも少し長くなっている。
【００２５】
図８は歯車９０の組付け箇所の構造を示した断面図、図９は関節部支持構造を示した断面図である。
【００２６】
図９において、５０は回動軸である。この回動軸５０は、第２ケース６０の筒部６１に収容保持されている軸受７５に摺動回転自在に嵌合可能な径大軸部５１と、歯車９０の欠円部を有する径大な孔部９６ｂに嵌合されてその歯車９０の相対回転を阻止する欠円軸部５２と、歯車の径小な孔部９６ａと第１ケース４０の筒部４１に収容保持されている軸受７１に嵌合可能な径小軸部５３とを同心状に有するまっすぐな軸体でなり、その径大軸部５１側の端部に係合片５４が固定され、径小軸部５３側の端部に係合溝５５が形成されている。
【００２７】
図２で説明したアーム部材１２３の基部には、図９に示されている二股状に分岐した取付片部１２５，１２６が連設されていて、一方側の取付片部１２５に、上記回動軸５０の径小軸部５３が挿通される孔部１２７が具備され、他方側の取付片部１２６に、上記回動軸５０の径大軸部５１が挿通される孔部１２８と上記回動軸５０の係合片５４を係合状態で収容する凹所１２９とが具備されている。また、二股状に分岐している取付片部１２５，１２６は、図９のように筐体３０の外側に相対回動自在に嵌め込まれる構成になっている。
【００２８】
次に、図２などで説明した関節部１２１を組み立てる手順の一例を図８及び図９を参照して説明する。
【００２９】
第１ケース４０が結合されていない第２ケース６０の筒部６１の内部に、その筒部６１の根元部分に達するまで軸受７５を圧入して収容保持させることにより、筒部６１を軸受７５の上方へ突出させておく。この状態で、歯車９０の環状凸部９９を、軸受７５の収容箇所よりも外側で筒部６１に嵌合することによって、当り面９８ｂを筒部６１の端面によって形成されている受面６３に重ね合わせる。この作業は、環状凸部９９を筒部６１に嵌合させるだけの作業であるため容易に行うことができ、しかも、筒部６１に環状凸部９９を嵌合させることによって、歯車９０が軸受７５に対して同心状に位置決めされる。この実施形態では、歯車９０に上記環状凸部９９に加えて径大な環状リブ９３を具備させてあり、その環状リブ９３が筒部６１に遊嵌合可能になっていて、環状凸部９９を筒部６１に嵌合させる際に環状リブ９３の内側に筒部６１を嵌め込むだけで、筒部６１に対し環状凸部９９がほゞ位置合わせされた状態になるので、そのようにすることによって、環状凸部９９を筒部６１に嵌合させる作業をきわめて容易に行うことができるようになるという利点がある。この利点は、図４に示したように、歯車９０が中間歯車８２の下側に配備されるために筒部６１が見えなくなるという状況の下で歯車９０の組込みを行う場合に特に有益である。
【００３０】
こうして歯車９０を第２ケース６０の内側に配備した後、第１ケース４０を第２ケース６０に重ね合わせる作業を行うけれども、その作業に先立って、第１ケース４０の筒部４１の内部に、その筒部４１の根元部分に達するまで軸受７１を圧入して収容保持させておくことにより、筒部４１を軸受７１よりも突出させておく。第１ケース４０を第２ケース６０に重ね合わせる作業では、第１ケース４０の筒部４１を、第２ケース６０の内側に上記のように配備されている歯車９０の環状凸部９７に筒部４１を外嵌合させて筒部４１の端面によって形成されている受面４３に当り面９８ａを重ね合わせる。このようにすると、歯車９０を介して第１ケース４０が第２ケース６０に対して位置合わせされるので、第１及び第２のケース４０，６０が確実に重ね合わされる。なお、第１及び第２のケース４０，６０はねじ止めなどの手段で結合されて筐体３０を形成する。
【００３１】
第１及び第２のケース４０，６０を結合することによって筐体３０を形成した後、図９のようにアーム部材１２３の二股状の取付片部１２５，１２６を筐体３０に嵌め込むと共に、それらの取付片部１２５，１２６の孔部１２７，１２８を、第１及び第２の各ケース４０，６０の円形孔４２，６２に合わせる。そして、回動軸５０を孔部１２８、円形孔６２、軸受７５、歯車９０の孔部９６ｂ及び孔部９６ａ、軸受７１、円形孔４２、孔部１２７の順に挿通させることによって、その回動軸５０の径小軸部５３を孔部９６ａ、軸受７１、円形孔４２、孔部１２７に挿通させ、欠円軸部５２を孔部９６ｂに嵌合させ、径大軸部５１を孔部１２８、円形孔６２、軸受７５に挿通させる。また、回動軸５０の係合片５４を取付片部１２６の凹所１２９に嵌め込むと共に、回動軸５０の係合溝５５に割りワッシャでなる止め具５７を嵌め込んで回動軸５０の抜け出しを阻止しておく。これにより、回動軸５０が２つの軸受７１，７５に摺動回転自在に支持され、歯車９０が回動軸５０に回転不能な状態に固定され、筐体３０とアーム部材１２３とが回動軸５０によって相対揺動可能に連結される。
【００３２】
図９に示した構造を備えた関節部１２１によると、歯車９０に伝達されたモータＭ（図４参照）の回転が回動軸５０と取付片部１２５，１２６とを介してアーム部材（図２参照）に伝達されるので、筐体３０とアーム部材１２３とが相対揺動する。そして、このような動作が行われる過程で、軸受７１や軸受７５が筒部４１や筒部６１の内部で軸線方向に位置ずれしたとしても、軸受７１については、その位置ずれの範囲が、筒部４１の底面（凹入部の底面）と環状凸部９７の端面との間の範囲に限られ、軸受７５については、その位置ずれの範囲が、筒部６１の底面（凹入部の底面）と環状凸部９９の端面との間の範囲に限られるため、それらの軸受７１，７５が筒部４１，６１から離脱してしまうというトラブルが起こり得ない。しかも、軸受７１，７５がたとえ位置ずれしたとしても、回動軸５０は軸受７１，７５によって摺動回転自在に支持されたままであるので、軸受７１，７５の位置ずれによって軸受７１，７５の機能が損なわれることはない。また、それぞれの軸受７１，７５は、環状凸部９７，９９によって開口が塞がれた筒部４１，６１の内部に収容保持されているため、軸受７１，７５と回動軸５０との摺動部分に塵埃が侵入して軸受７１，７５の機能が損なわれるという事態も起こりにくい。さらに、軸受７１，７５が筒部４１，６１の根元部分のところに圧入されている正常な状態では、軸受７１，７５と歯車９０の環状凸部９７，９９との間に隙間が形成されるため、両者が擦れ合って回動軸５０の円滑な回動が損なわれることはない。
【００３３】
この実施形態では、動物ロボットの関節部分に本発明を適用した事例を説明したけれども、本発明は、動物ロボット以外のロボット、たとえば人間を模したロボットや植物を模したロボットの関節部分にも適用することが可能である。
【００３４】
【発明の効果】
以上のように、本発明によれば、回動軸を支持する軸受に安価な筒体を用いることができるのでコストダウンを図りやすくなる。また、軸受に筒体を用いたので、軸受や回動軸の組込みにそれほど高い精度が要求されなくなり、そのことが、製作コストの低減に役立つ。さらに、軸受の塵埃からの保護が図られ、併せて、回動軸に回転を伝達するための歯車の取付けやその歯車に対する回動軸の取付け、さらには関節部の組立てを容易に行うことができるようになる。
【図面の簡単な説明】
【図１】本発明を適用した動物ロボットの概略部分側面図である。
【図２】同ロボットのモジュールと脚部とを示した概略側面図である。
【図３】図２のＩＩＩ矢視図である。
【図４】歯車列を示した説明図である。
【図５】歯車を片側から見た平面図である。
【図６】歯車を他側から見た平面図である。
【図７】図５のＶＩＩ−ＶＩＩ線に沿う部分の概略断面図である。
【図８】歯車の組付け箇所の構造を示した断面図である。
【図９】関節部支持構造を示した断面図である。
【符号の説明】
３０筐体（一方側部材）
４０第１ケース
４１，６１筒部（凹入部）
４２，６２，１２７，１２８孔部
４３，６３受面
５０回動軸
６０第２ケース
７１，７５軸受
９０歯車
９３環状リブ
９７，９９環状凸部
９８ａ，９８ｂ当り面
１２１関節部
１２３アーム部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a joint support structure for a robot, for example, a joint support structure for a robot employed in joints such as front and rear legs of an animal robot.
[0002]
[Prior art]
In an animal robot, for example, in order to move the front and rear legs, it is possible to employ a means in which a rotation shaft is provided at a joint provided on the leg and the rotation of the motor is transmitted to the rotation shaft. In this case, it is necessary to support the rotating shaft with a bearing. Therefore, conventionally, a bearing has been adopted as a bearing.
[0003]
[Problems to be solved by the invention]
However, adopting a bearing as a bearing to form a joint not only raises the cost of the bearing due to its high cost, but also includes the accuracy of assembly of the bearing into the casing that forms the legs, the rotation axis, etc. In addition to the high accuracy required for assembly, there is a problem that skill is required for molding of required parts and assembly of joints.
[0004]
The present invention has been made in view of the above problems, and based on the use of an inexpensive cylinder for the bearing that supports the rotating shaft, the robot that does not require such a high degree of accuracy for the incorporation of the bearing and the rotating shaft. It is an object to provide a joint support structure.
[0005]
Further, the present invention protects the bearing from dust, and at the same time, it is easy to attach a gear for transmitting rotation to the rotating shaft, attach the rotating shaft to the gear, and further assemble the joint portion. It is an object of the present invention to provide a joint support structure for a robot that can be performed in a simple manner.
[0006]
[Means for Solving the Problems]
In the joint support structure for a robot according to the present invention, two members are connected to each other so as to be relatively swingable by a rotation shaft, and a rotation transmission gear is attached to the rotation shaft.
[0007]
And the bearing which consists of a cylindrical body externally fitted by the said rotation axis so that relative sliding rotation is possible is comprised in the one side member of two said members, and the depth longer than the height dimension of the bearing The annular convex portion of the annular convex portion concentrically provided in the gear and the annular contact surface located outside the annular convex portion is accommodated and held inside the concave portion having a dimension. It is fitted to the recessed portion so as to be slidable and rotatable outside the bearing receiving location, and the contact surface is slidably and rotatably superimposed on an annular receiving surface provided around the opening of the recessed portion. ing.
[0008]
With this configuration, the cylindrical bearing is positioned by being housed and held in the recessed portion of the one-side member, and the rotating shaft is supported by the bearing positioned in such a manner as to be slidably rotatable. Therefore, it is not necessary to use an expensive bearing. Further, since the bearing made of a cylindrical body is accommodated and held inside the recessed portion whose opening is closed by fitting the annular convex portion of the gear, the annular convex portion of the gear seals the recessed portion, In addition, the contact surface of the gear overlaps with the annular receiving surface around the opening of the recessed portion, thereby preventing dust from entering the recessed portion. Therefore, it is difficult for a situation in which dust enters the sliding portion between the rotating shaft and the bearing to impair the smoothness of the rotating operation of the rotating shaft.
[0009]
In the present invention, the bearing is housed and held in the recessed portion in a press-fitted state, and the facing distance between the end surface of the annular convex portion and the bottom surface of the recessed portion is longer than the height of the bearing. It is desirable that According to this, it is possible to form a gap between the end face of the annular convex portion of the gear and the bearing so that the annular convex portion of the gear does not rub against the bearing. The rotation of the gear is smoothly transmitted to the rotating shaft. In addition, since the opening of the recessed portion that accommodates and holds the bearing is blocked by the annular convex portion of the gear, even if a situation occurs in which the bearing is displaced in the axial direction with respect to the rotating shaft, The trouble that the bearing is detached from the recessed portion cannot occur, and even if the bearing is displaced in the axial direction with respect to the rotating shaft, the function as the bearing is not impaired.
[0010]
In the present invention, each of the bearing, the one-side member having the receiving surface and the recessed portion, and the gear having the annular convex portion and the contact surface is preferably made of a synthetic resin molded body. If the bearing, the one side member, the gear, and the like are made of a synthetic resin molded body in this way, those parts become inexpensive and it is easy to promote cost reduction.
[0011]
In the present invention, the one side member is a flat casing divided into first and second cases that are coupled to each other to form a gear box, and the recessed portion that accommodates and holds the bearing is the first. Each of the first and second cases is provided in each of the cases, and the annular protrusions provided concentrically at both ends in the axial direction of the gear are respectively fitted to the respective recessed portions so as to be slidably rotatable. In addition, the contact surface located outside the annular convex portions is slidably and separately superimposed on the receiving surface provided around the openings of the concave portions. It is desirable to adopt.
[0012]
According to this, it becomes possible to assemble a flat housing by the procedure of joining the second case to the first case provided with a gear, for example. In that case, in particular, after the bearing is fitted into the recessed portion of the first case, the annular convex portion on one side of the gear is fitted into the recessed portion, and the contact surface on one side is the receiving surface around the opening of the recessed portion. Since the gear is positioned with respect to the first case, the assembling work for coupling the second case to the first case can be easily performed, and the second case is coupled to the first case. When the assembly work to be performed, the recessed portion of the second case is fitted to the annular convex portion on the other side of the gear, and the receiving surface around the opening of the recessed portion is overlapped with the contact surface on the other side. Therefore, the operation of aligning the second case with the first case is facilitated.
[0013]
In the present invention, the recessed portion provided on at least one side of the first and second cases is formed by the internal space of the cylindrical portion provided in the case on the one side, and the axial direction of the gear It is desirable to adopt a configuration in which one side surface is provided with an annular rib that is externally fitted to the cylindrical portion. According to this, when the gear is arranged in the case on one side, the operation of fitting the cylindrical portion forming the recessed portion into the annular recess formed by the annular convex portion and the annular rib of the gear. Through which the gear can be deployed in the proper position on the case on one side. Therefore, it is possible to easily dispose the gear to the case on one side. This effect is more remarkably exhibited by adopting a configuration in which the annular rib is loosely fitted to the outside of the cylindrical portion.
[0014]
In the present invention, it is desirable that the pivot shaft is a straight shaft body that is inserted through holes provided in the two members concentrically with the recessed portion.
[0015]
According to this, by inserting the rotation shaft into the hole portions of the two members, the two members are connected, and the rotation shaft is connected to the gear or the bearing incorporated in the one side member. It can be inserted.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
1 is a schematic partial side view of an animal robot to which the present invention is applied, FIG. 2 is a schematic side view showing a module 10 and a front leg 120 of the robot, and FIG. 3 is a view taken in the direction of arrow III in FIG. .
[0017]
As shown in FIG. 1, the robot according to the present invention has a structure 100, in which a front and rear legs 120 and 130 are swung back and forth in the body 110 in addition to a neck and a head (not shown). It is attached to be able to. In addition, there are joint portions 121, 122, 131, 132 in the leg portions 120, 130 so that the movement of the joint portions 121, 122, 131, 132 is the same as that of the animal leg. It has become. This robot operates using a built-in battery as a power source.
[0018]
The fuselage 110 is formed by combining a plurality of modules, and one of these modules is indicated at 10 in FIG. As shown in FIG. 1 or FIG. 2, a housing 30, which is a member forming a base side portion of the front leg portion 120, is attached to the module 10 via the shaft body 20. Furthermore, an arm member 123, which is another member forming another part of the leg part 120, is connected to the housing 30 via the joint part 121, and further, a leg tip part is formed on the arm member 123. The tip member 124 is connected through the joint 122. The rear leg 130 has substantially the same configuration as the front leg 120.
[0019]
The housing 30 forms a gear box, and a gear train, which will be described later, is provided inside the housing 30. Further, a cover 30a is screwed to the outside of the housing 30, and an electric control component such as a wiring board is disposed in an internal space surrounded by the housing 30 and the cover 30a.
[0020]
Further, as seen in FIG. 3, the housing 30 is divided into a first case 40 on the module 10 side and a second case 60 coupled to the first case 40. Flattened by joining 60.
[0021]
FIG. 4 shows a gear train arranged inside the housing 30 as a gear box, together with a second case 60 forming a case on one side of the housing 30. As shown in the figure, this gear train includes an output gear 81 of the motor M, a plurality of intermediate gears 82 meshed with the output gear 81, and the rotation of the output gear 81 via these intermediate gears 82. The final gear 90 is transmitted at a reduced speed, and the final gear 90 (hereinafter simply referred to as “gear 90”) is incorporated in the joint portion 121 shown in FIG.
[0022]
5 is a plan view of the gear 90 as seen from one side, FIG. 6 is a plan view of the gear 90 as seen from the other side, and FIG. 7 is a schematic cross-sectional view of a portion along the line VII-VII in FIG.
[0023]
This gear 90 is an integrally molded body of synthetic resin, and has a toothless portion 91 in a substantially half-circumferential portion, and the gear 90 is provided between the outer peripheral portion of the toothless portion 91 and the outer peripheral portion of the toothed portion 92. Are provided with annular ribs 93 and 94 projecting on one side or the other side in the axial direction. In addition, a cylindrical boss portion 95 protruding to the other side in the axial direction is integrally provided at the center portion of the gear 90. The boss 95 is provided with a small-diameter circular hole 96a and a large-diameter hole 96b having a notch, and a circular end on the axial end surface of the boss 95. An annular protrusion 97 and an annular contact surface 98a located outside the annular protrusion 97 are provided concentrically. On the other hand, an annular convex portion 99 that is concentric with the annular convex portion 97 is provided on one axial side of the gear 90. Note that, in the illustrated example, the annular convex portion 99 has three portions spaced apart at equal intervals in the circumferential direction, and is removed over a certain width.
[0024]
The first and second cases 40, 60 to which the gear 90 is assembled are also integrally formed of synthetic resin, and cylindrical cases projecting inwardly from the cases 40, 60, respectively. A recessed portion formed by the internal spaces 41 and 61 is provided. The cylindrical bearings 71 and 75 are accommodated and held in a press-fitted state inside the cylindrical portions 41 and 61, and the cases 40 and 60 are concentric with the cylindrical portions 41 and 61. Circular holes 42 and 62 are provided. The bearings 71 and 75 are also made of a synthetic resin molding. Here, the depth dimension (height dimension of the cylinder part 41) of the cylindrical part 41 of the first case 40 that accommodates and holds the bearing 71 therein is longer than the height dimension (axial length) of the bearing 71. ing. Therefore, the cylinder portion 41 protrudes from the bearing 71 that is press-fitted to the root position of the cylinder portion 41. Similarly, the depth dimension of the cylindrical portion 61 (the height dimension of the cylindrical portion 61) of the second case 60 that accommodates and holds the bearing 75 therein is larger than the height dimension (axial length) of the bearing 75. It is getting longer. Therefore, the cylindrical portion 61 protrudes beyond the bearing 75 that is press-fitted to the root position of the cylindrical portion 61. Further, the depth dimension of the cylindrical portion 41 is slightly longer than the dimension obtained by combining the height dimension of the bearing 71 and the height dimension of the annular convex portion 97 provided on the gear 90 described above. Similarly, the depth dimension of the cylindrical portion 61 is slightly longer than the dimension obtained by combining the height dimension of the bearing 75 and the height dimension of the annular convex portion 99 provided in the gear 90 described above. .
[0025]
FIG. 8 is a cross-sectional view showing the structure of the assembly location of the gear 90, and FIG. 9 is a cross-sectional view showing the joint support structure.
[0026]
In FIG. 9, 50 is a rotation axis. The rotating shaft 50 has a large-diameter shaft portion 51 that can be slidably and rotatably fitted to a bearing 75 that is accommodated and held in the cylindrical portion 61 of the second case 60, and a large-diameter portion that has a missing circular portion of the gear 90. A non-circular shaft portion 52 that is fitted in the hollow portion 96b to prevent relative rotation of the gear 90, a small diameter hole portion 96a of the gear, and a bearing 71 that is housed and held in the cylindrical portion 41 of the first case 40. The small-diameter shaft portion 53 is a straight shaft body having a concentric shape, and an engagement piece 54 is fixed to an end portion on the large-diameter shaft portion 51 side. An engaging groove 55 is formed in the portion.
[0027]
The bifurcated attachment pieces 125 and 126 shown in FIG. 9 are connected to the base of the arm member 123 described with reference to FIG. 2, and the above-described rotation is made to the attachment piece 125 on one side. A hole 127 through which the small-diameter shaft portion 53 of the shaft 50 is inserted is provided, and the hole 128 through which the large-diameter shaft portion 51 of the rotation shaft 50 is inserted and the rotation are inserted into the attachment piece 126 on the other side. A recess 129 for receiving the engaging piece 54 of the shaft 50 in an engaged state is provided. Further, the attachment pieces 125 and 126 branched in a bifurcated shape are configured to be fitted to the outside of the housing 30 so as to be relatively rotatable as shown in FIG.
[0028]
Next, an example of a procedure for assembling the joint part 121 described in FIG. 2 and the like will be described with reference to FIGS.
[0029]
The cylindrical portion 61 of the bearing 75 is accommodated by press-fitting and holding the bearing 75 in the cylindrical portion 61 of the second case 60 to which the first case 40 is not joined until the base portion of the cylindrical portion 61 is reached. Project upward. In this state, the contact surface 98b is formed on the receiving surface 63 formed by the end surface of the cylindrical portion 61 by fitting the annular convex portion 99 of the gear 90 to the cylindrical portion 61 outside the housing location of the bearing 75. Overlapping. This operation can be easily performed because it is only an operation for fitting the annular convex portion 99 to the cylindrical portion 61. Moreover, by fitting the annular convex portion 99 to the cylindrical portion 61, the gear 90 is a bearing. It is positioned concentrically with respect to 75. In this embodiment, the gear 90 is provided with an annular rib 93 having a large diameter in addition to the annular protrusion 99, and the annular rib 93 can be loosely fitted to the cylindrical portion 61. When the cylindrical portion 61 is fitted into the cylindrical portion 61, the annular convex portion 99 is almost aligned with the cylindrical portion 61 simply by fitting the cylindrical portion 61 inside the annular rib 93. Thus, there is an advantage that the operation of fitting the annular convex portion 99 to the cylindrical portion 61 can be performed very easily. This advantage is particularly beneficial when the gear 90 is assembled in a situation where the cylindrical portion 61 becomes invisible because the gear 90 is disposed below the intermediate gear 82 as shown in FIG. .
[0030]
Thus, after the gear 90 is arranged inside the second case 60, the first case 40 is superposed on the second case 60. Prior to the work, the inside of the cylindrical portion 41 of the first case 40, The cylindrical portion 41 is protruded from the bearing 71 by press-fitting and holding the bearing 71 until reaching the base portion of the cylindrical portion 41. In the operation of superimposing the first case 40 on the second case 60, the cylindrical portion 41 of the first case 40 is formed on the annular convex portion 97 of the gear 90 disposed as described above inside the second case 60. 41 is fitted outside and the contact surface 98a is overlapped with the receiving surface 43 formed by the end surface of the cylindrical portion 41. If it does in this way, since the 1st case 40 is aligned with respect to the 2nd case 60 via gear 90, the 1st and 2nd cases 40 and 60 are piled up certainly. The first and second cases 40 and 60 are joined by means such as screwing to form the housing 30.
[0031]
After the case 30 is formed by joining the first and second cases 40 and 60, the bifurcated attachment pieces 125 and 126 of the arm member 123 are fitted into the case 30 as shown in FIG. The holes 127 and 128 of the attachment pieces 125 and 126 are aligned with the circular holes 42 and 62 of the first and second cases 40 and 60, respectively. The rotation shaft 50 is inserted through the hole 128, the circular hole 62, the bearing 75, the hole 96 b and the hole 96 a of the gear 90, the bearing 71, the circular hole 42, and the hole 127 in this order, thereby rotating the rotation shaft 50. The small-diameter shaft portion 53 of 50 is inserted into the hole portion 96a, the bearing 71, the circular hole 42, and the hole portion 127, the cut-out circular shaft portion 52 is fitted into the hole portion 96b, and the large-diameter shaft portion 51 is inserted into the hole portion 128, The circular hole 62 and the bearing 75 are inserted. In addition, the engaging piece 54 of the rotating shaft 50 is fitted into the recess 129 of the mounting piece 126, and the stopper 57 made of a split washer is fitted into the engaging groove 55 of the rotating shaft 50. Prevent the escape of. As a result, the rotation shaft 50 is supported by the two bearings 71 and 75 so as to be slidably rotatable, the gear 90 is fixed to the rotation shaft 50 in a non-rotatable state, and the housing 30 and the arm member 123 are rotated. The shaft 50 is connected so as to be relatively swingable.
[0032]
According to the joint portion 121 having the structure shown in FIG. 9, the rotation of the motor M (see FIG. 4) transmitted to the gear 90 is transmitted through the rotation shaft 50 and the attachment pieces 125 and 126 to the arm member (see FIG. 9). 2), the casing 30 and the arm member 123 are relatively swung. And even if the bearing 71 and the bearing 75 are displaced in the axial direction inside the cylindrical portion 41 and the cylindrical portion 61 in the process in which such an operation is performed, the range of the positional deviation of the bearing 71 is the cylinder. It is limited to the range between the bottom surface of the portion 41 (the bottom surface of the recessed portion) and the end surface of the annular convex portion 97, and the bearing 75 has a range of positional deviation between the bottom surface of the cylindrical portion 61 (the bottom surface of the recessed portion). Since it is limited to the range between the end surface of the annular convex part 99, the trouble that those bearings 71 and 75 will detach | leave from the cylinder parts 41 and 61 cannot occur. Moreover, even if the bearings 71 and 75 are displaced, the rotation shaft 50 remains supported by the bearings 71 and 75 so as to be slidably rotatable. Will not be damaged. Further, since the bearings 71 and 75 are accommodated and held in the cylindrical portions 41 and 61 whose openings are closed by the annular convex portions 97 and 99, the sliding between the bearings 71 and 75 and the rotary shaft 50 is retained. A situation in which dust enters the moving part and the functions of the bearings 71 and 75 are impaired is unlikely to occur. Further, in a normal state where the bearings 71 and 75 are press-fitted at the base portions of the cylindrical portions 41 and 61, a gap is formed between the bearings 71 and 75 and the annular convex portions 97 and 99 of the gear 90. Therefore, the two do not rub against each other and the smooth rotation of the rotation shaft 50 is not impaired.
[0033]
In this embodiment, an example in which the present invention is applied to a joint portion of an animal robot has been described. However, the present invention is also applied to a joint portion of a robot other than an animal robot, for example, a robot imitating a human being or a robot imitating a plant. Is possible.
[0034]
【The invention's effect】
As described above, according to the present invention, an inexpensive cylinder can be used for the bearing that supports the rotating shaft, so that the cost can be easily reduced. Further, since a cylindrical body is used for the bearing, so high accuracy is not required for the incorporation of the bearing and the rotating shaft, which helps to reduce the manufacturing cost. Further, the bearing is protected from dust, and at the same time, the gear for transmitting the rotation to the rotating shaft, the mounting of the rotating shaft to the gear, and the assembly of the joint portion can be easily performed. become able to.
[Brief description of the drawings]
FIG. 1 is a schematic partial side view of an animal robot to which the present invention is applied.
FIG. 2 is a schematic side view showing a module and legs of the robot.
FIG. 3 is a view taken in the direction of arrow III in FIG.
FIG. 4 is an explanatory diagram showing a gear train.
FIG. 5 is a plan view of the gear viewed from one side.
FIG. 6 is a plan view of the gear viewed from the other side.
7 is a schematic cross-sectional view of a portion taken along line VII-VII in FIG.
FIG. 8 is a cross-sectional view showing the structure of the assembly position of the gear.
FIG. 9 is a cross-sectional view showing a joint support structure.
[Explanation of symbols]
30 Housing (one side member)
40 First case 41, 61 Tube portion (recessed portion)
42, 62, 127, 128 Hole 43, 63 Receiving surface 50 Rotating shaft 60 Second case 71, 75 Bearing 90 Gear 93 Annular rib 97, 99 Annular convex part 98a, 98b Contact surface 121 Joint part 123 Arm member

Claims

A joint support structure for a robot in which two members are connected to each other by a rotation shaft so as to be relatively swingable, and a rotation transmission gear is attached to the rotation shaft.
A cylindrical bearing externally fitted to the rotating shaft so as to be relatively slidable and rotatable is provided on one of the two members and has a depth dimension longer than the height dimension of the bearing. The annular convex portion of the annular convex portion concentrically provided on the gear and the annular contact surface located outside the annular convex portion is accommodated and held in the concave portion having the bearing. Is fitted to the recessed portion so as to be slidable and rotatable outside the receiving portion, and the contact surface is slidably and rotatably superimposed on an annular receiving surface provided around the opening of the recessed portion. A robot joint support structure characterized by the above.

The bearing is housed and held in the recessed portion in a press-fit state, and the facing distance between the end surface of the annular convex portion and the bottom surface of the recessed portion is longer than the height of the bearing. 1. The joint support structure for a robot according to 1.

The said bearing, the said one side member which has the said receiving surface and the said recessed part, and each of the said gearwheel which has the said cyclic | annular convex part and the said contact surface consist of a synthetic resin molding. The joint support structure of the robot.

The one side member is a flat casing divided into first and second cases that are coupled to each other to form a gear box, and the recessed portion that houses and holds the bearing is the first and second cases. The annular projections provided concentrically on the respective axial ends of the gears are respectively fitted to the respective recessed portions so as to be slidably rotatable. 4. The contact surface located outside the annular convex portions is slidably and separately superimposed on the receiving surface provided around the opening of each concave portion. The joint support structure for a robot according to any one of the above.

The recessed portion provided on at least one side of the first and second cases is formed by an internal space of a cylindrical portion provided in the case on the one side, and on one side surface in the axial direction of the gear, 5. The joint support structure for a robot according to claim 4, further comprising an annular rib fitted to the cylindrical portion.

The joint support structure for a robot according to claim 5, wherein the annular rib is loosely fitted to the outside of the cylindrical portion.

The robot according to any one of claims 1 to 6, wherein the rotation shaft is a straight shaft that is inserted through holes provided in the two members concentrically with the recessed portion. The joint support structure.