JP2004291173A

JP2004291173A - Arm type robot

Info

Publication number: JP2004291173A
Application number: JP2003088543A
Authority: JP
Inventors: Masatoshi Oshima; 正歳大島
Original assignee: Sanyo Machine Works Ltd
Current assignee: Sanyo Machine Works Ltd
Priority date: 2003-03-27
Filing date: 2003-03-27
Publication date: 2004-10-21
Anticipated expiration: 2023-03-27
Also published as: JP4048142B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small, lightweight, and very rigid arm type robot which carries out high speed operation, and copes with a variety of robot works. <P>SOLUTION: The arm type robot comprises: a pair of first and second ascending/descending bodies 20, 30 which are arranged on right and left sides of a pair of columns 11a, 11b so as to independently ascend and descend; a third ascending/descending body 40 which ascends and descends the column 11a independently of the first ascending/descending body 20; a head portion 52 which carries an automatic working machine 58; a pair of first and second parallel link arm portions 51a, 51b which are connected to the first ascending/descending body 20 and the head portion 52 at both ends and perform a parallel link motion in a vertical plane; and a drive arm 60 for horizontally swivelling the respective parallel link arm portions 51a, 51b in the right and left directions. In addition, the arm type robot is configured such that the direction of the head portion 52 and the automatic working machine 58 with respect to the horizontal direction is changed by changing the relative height of the respective ascending/descending bodies 20, 30. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、ナットランナーなどの自動作業機を水平な直交二方向（Ｘ−Ｙ方向）方向と略鉛直な上下方向（Ｚ方向）のいずれにも自在に移動させるアーム式ロボットに関する。
【０００２】
【従来の技術】
自動車の製造組立ラインで使用されるナットランナーを水平方向と上下方向に自在に移動させるロボットとして一般的なものに、直交ロボットとスカラ型アーム式ロボットがある。前者直交ロボットは、水平な直交二方向に移動するテーブルを使用するため、水平な幅方向に大きな設置スペースを必要として、製造組立ラインでの設置にスペース的な制約が多い。また、後者スカラ型アーム式ロボットの場合も、後述するように幅方向に大きな設置スペースを必要とする。
【０００３】
スカラ型アーム式ロボット（例えば、特許文献１参照）の具体例を、図６に示すと、このロボット１は、略鉛直な主軸２の上端部に第１水平アーム３の後端部を回転可能に連結し、第１水平アーム３の先端部に第２水平アーム４の後端部を回転可能に連結し、第２水平アーム４の先端部の軸受５で垂直軸６を上下動可能に連結している。垂直軸６に自動作業機の例えばナットランナー７が固定され、各水平アーム３、４の各々が独自に水平方向に旋回することで、軸受５と垂直軸６から成るロボット作業用ヘッド部８とナットランナー７が水平方向に移動する。図７に示す製造組立ラインＬに沿った搬送体上のワーク９は、図中のＰ点とＱ点で示す複数の被ねじ締め部を有し、これら被ねじ締め部の真上にナットランナー７が順に移動するように、第１水平アーム３と第２水平アーム４が独自に旋回運動する。
【０００４】
【特許文献１】
特開２０００−１４１２５７号公報（図３、図５）
【０００５】
【発明が解決しようとする課題】
図７の鎖線で示すように、第１水平アーム３と第２水平アーム４が例えば一直線状の連結状態にあるときにワーク９上の最も離れた１点Ｐｂにヘッド部８が移動してねじ締め動作を行い、また、第１水平アーム３と第２水平アーム４が互いに水平方向にく字状に屈曲して最も近い１点Ｐａにヘッド部８が移動してねじ締め動作を行うとすると、図６のアーム式ロボット１は、ロボット前方の左右両側方に各水平アーム３、４が屈曲して食み出すだけの大きな幅方向スペースＳ１を必要とし、この幅方向スペースＳ１がアーム式ロボット１の床上設置スペースを大きくしていた。また、複数台のアーム式ロボット１を床上に併設する場合、隣接する一対のロボットの間隔を幅方向スペースＳ１の２倍以上にする必要があって、複数台のロボットを省スペースで併設することが難しい。
【０００６】
また、上記アーム式ロボット１の各水平アーム３、４とヘッド部８は、各々の必要とする機能のために幅、厚さ、径の大きな大形重量物となる傾向が強くて、速い動きをさせることが難しい。特に、ヘッド部８は垂直軸６を上下動させる動力源などで大径構造となり、例えば図７に示すワーク９上の所定の最小的な間隔Ｗ１で接近した２点ＰａとＱａの被ねじ締め部を２台の同じアーム式ロボットで同時にねじ締めしようとする場合、２台のロボットの各ヘッド部同士が干渉し合って、同時にねじ締めすることができないことがある。そこで、１台のロボットで１点Ｐａをねじ締めすると、この１点Ｐａに最も接近した他の１点Ｑａにヘッド部８を移動させてねじ締めしているため、接近する一対の点Ｐａ、Ｑａのねじ締め作業性を上げることが難しい。また、図示しないが１台のヘッド部に一対のナットランナーを配備して、上記の２点Ｐａ、Ｑａを同時にねじ締めするようにして作業性を上げることことが可能であるが、一対のナットランナーのためにヘッド部の重量と外径が倍増して、水平アームが高剛性の大形重量構造となり、高速運転をさせることが難しくなる。
【０００７】
本発明の目的は、設置スペースの縮小化が容易であり、アームの小形軽量化で速い動きを可能にした、かつ、自動作業機で作業を受けるワークの種類変更に自在に対応可能としたアーム式ロボットを提供することにある。
【０００８】
【課題を解決するための手段】
本発明は上記目的を達成するため、略鉛直な並列の定軌道を独自に昇降する左右一組の第１昇降体２０及び第２昇降体３０と、第１昇降体２０が昇降する定軌道を第１昇降体と別に昇降する第３昇降体４０と、第１昇降体２０に後端部が上下左右方向に回転可能に連結され、先端部がロボット作業用ヘッド部５２に上下左右方向に回転可能に連結されて、後端部を基点に略鉛直な平面で上下に平行リンク運動する複数の平行アーム５３ａを備えた第１平行リンクアーム部５１ａと、第２昇降体３０に後端部が上下左右方向に回転可能に連結され、先端部がヘッド部５２に上下左右方向に回転可能に連結されて、後端部を基点に略鉛直な平面で上下に平行リンク運動する複数の平行アーム５３ｂを備えた第２平行リンクアーム部５１ｂとを有するリンク機構５０と、第３昇降体４０に後端部が上下左右方向に回転可能に連結され、先端部が第１平行リンクアーム部５１ａに上下方向に回転可能に連結されて第１平行リンクアーム部５１ａが平行リンク運動する略鉛直な平面で上下揺動する駆動アーム６０と、前記定軌道に設置されて第１〜第３昇降体２０〜４０を独自に昇降させる第１〜第３駆動手段７０〜９０と、第３昇降体４０に設置されて駆動アーム６０を水平方向に回転揺動させる第４駆動手段１００とを具備したことを特徴とする（請求項１の発明）。
【０００９】
ここで、略鉛直な並列の定軌道は、略鉛直な左右一対の支柱１１ａ、１１ｂや、この支柱に固定されたガイドレール、同様な支柱に形成されたガイド溝で構成される。この並列の定軌道に沿って第１昇降体２０と第２昇降体３０の左右一組が同方向に、又は、反対方向に昇降し、或いは、一方が停止して他方だけが昇降する。第１昇降体２０と第３昇降体４０が同じ定軌道の上部と下部に分かれて独自に昇降する。第１平行リンクアーム部５１ａの平行アーム５３ａは、略鉛直な平面に沿って上下に平行リンク運動する２本又は２本以上の同一長さの直線状の鋼性アームで、この複数の各平行アーム５３ａの後端部が第１昇降体２０に連結され、先端部がロボット作業用ヘッド部５２に連結されて、鉛直面で平行四辺形を形成する第１平行リンクアーム部５１ａが構築される。同様にして第２平行リンクアーム部５１ｂが複数本の平行アーム５３ｂで構成される。左右一対の第１、第２平行リンクアーム部５１ａ、５１ｂが独自に鉛直な平面で平行リンク運動して、ヘッド部５２が鉛直な姿勢を保持した状態で前後左右上下に移動する。ヘッド部５２は一対の平行リンクアーム部５１ａ、５１ｂで支持されることから安定した高剛性を保持して、ヘッド部５２に単機又は複数機のナットランナーなどの自動作業機を安定して保持する。第１昇降体２０と第２昇降体３０を独自に昇降させて両者の相対的な高さを変位させることで、ヘッド部５２が水平方向で回転動作して自動作業機の水平方向の向きを自在に変位させる。
【００１０】
また、駆動アーム６０は第１平行リンクアーム部５１ａを水平方向左右に揺動回転させ、この揺動回転力で第２平行リンクアーム部５１ｂも一体的に揺動回転して、ヘッド部５２を水平な左右方向に移動させる。この駆動アーム６０は、リンク機構５０を揺動回転させると共に、リンク機構５０を補強して各アームに構造簡単で軽量なものの適用を可能にする。第１〜第３駆動手段７０〜９０と第４駆動手段１００の駆動源は、サーボモータやシリンダが適用できる。
【００１１】
本発明においては、前記並列の定軌道を略鉛直に固設した左右一対の支柱１１ａ、１１ｂの前面に配設し、この左右一対の支柱１１ａ、１１ｂの間と各支柱の外側面に第１〜第３駆動手段７０〜９０を分配して配設することができる（請求項２の発明）。左右一対の支柱１１ａ、１１ｂを所定間隔で対峙させて、柱間に例えば第３駆動手段９０を配備し、両柱の外側面に第１駆動手段７０と第２駆動手段８０を配備することで、ロボット全体の幅方向の設置スペースが最小限近くまで小さくできる。
【００１２】
また、本発明においては、ロボット作業用ヘッド部５２を、水平方向に所定配列で複数の自動作業機を着脱自在に支持する構造にすることができる（請求項３の発明）。この場合、ヘッド部５２をナットランナーやビス止め用電動工具、クリップ立て工具、外観検査機器などの自動作業機を着脱自在に支持する汎用構造にすることで、各種の自動作業機が交換できる汎用ロボットが提供できる。また、１台のヘッド部５２に複数の自動作業機を設置して、各自動作業機を同時に作動させることで、ねじ締めなどの作業性の改善が図れる。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態を図１乃至図５を参照して説明する。
【００１４】
図１及び図２に示すアーム式ロボット１０は、床上に略鉛直に固設された左右一対の支柱１１ａ、１１ｂと、各支柱１１ａ、１１ｂの前面で独自に上下運動する第１昇降体２０及び第２昇降体３０と、第１昇降体２０が昇降する一方の支柱１１ａに沿って第１昇降体２０と別に昇降する第３昇降体４０と、第１昇降体２０から前方に延在する第１平行リンクアーム部５１ａ及び第２昇降体３０から前方に延在する第２平行リンクアーム部５１ｂの各先端部に連結された共通１台のロボット作業用ヘッド部５２を備えたリンク機構５０と、第３昇降体３０から前方に延在する駆動アーム６０と、第１〜第３昇降体２０〜４０を独自に昇降させる第１〜第３駆動手段７０〜９０と、駆動アーム６０を水平方向に回転揺動させる第４駆動手段１００を備える。
【００１５】
左右一対の支柱１１ａ、１１ｂは一定間隔で平行に対向する角柱で、下端部に固定した台座１２で床上に固定され、各々の上端部が連結体１３で連結される。一対の支柱１１ａ、１１ｂが並ぶ水平方向をＸ方向、Ｘ方向と直交する水平方向をＹ方向とし、鉛直方向をＺ方向とする。第１昇降体２０と第２昇降体３０の各々はＸ方向に平行な略鉛直な矩形板で、平常時はほぼ同じ高さに並置される。一対の各支柱１１ａ、１１ｂの前面にＺ方向にガイドレール１４が配設され、一方の支柱１１ａのガイドレール１４の上部領域に第１昇降体２０が上下動可能に連結され、下部領域に第３昇降体４０が上下動可能に連結される。他方の支柱１１ｂのガイドレール１４は支柱１１ｂの上部領域だけに設置されて、このガイドレール１４に第２昇降体３０が上下動可能に連結される。また、必要に応じて各支柱１１ａ、１１ｂには第１〜第３昇降体２０〜４０の上下位置を検知する複数のセンサー１５が設置される。
【００１６】
第１昇降体２０は、支柱１１ａのガイドレール１４の前面側を上下動する略鉛直な支持板２１と、支持板２１の裏面両側にＺ方向に設置された複数のガイドローラ２２と、支持板２１の前面中央部に配設された鉛直な１本のアーム連結用回転軸２４を有する。回転軸２４は、支持板２１の前面上下両端から前方に突設された軸受板２３に水平方向に回転可能に連結される。支持板２１の裏面両側の各ガイドローラ２２が対応するガイドレール１４を両側面から挟持して、支持板２１の上下運動をガイドする。回転軸２４の上下端部に突設した上下一対のブラケット２５にピンを介して２本の平行な平行アーム５３ａの後端部が上下方向に回転可能に連結される。２本の平行アーム５３ａは同一長さの剛性アームで、各々の先端部が略鉛直な平板であるヘッド部５２の裏面上下２箇所に上下左右方向に回転可能に連結される。２本の平行な平行アーム５３ａと回転軸２４とヘッド部５２の４点の連結点が平行四辺形の頂点に位置して、鉛直な平面で上下に平行リンク運動する第１平行リンクアーム部５１ａが構築される。
【００１７】
第２昇降体３０は、第１昇降体２０と同一構造のものでよく、支柱１１ｂのガイドレール１４の前面側を上下動する略鉛直な支持板３１と、支持板２１の裏面両側にＺ方向に設置された複数のガイドローラ３２と、支持板３１の前面中央部に配設された鉛直な１本のアーム連結用回転軸３４を有する。支持板３１の前面上下両端から前方に突設された軸受板３３に回転軸３４の上下端部が水平方向に回転可能に連結される。回転軸３４の上下端部に突設した上下一対のブラケット３５にピンを介して２本の平行な平行アーム５３ｂの後端部が上下方向に回転可能に連結される。２本の平行アーム５３ｂは平行アーム５３ａと同一長さの剛性アームで、各々の先端部がヘッド部５２の裏面上下２箇所に上下左右方向に回転可能に連結される。この２本の平行アーム５３ｂと回転軸３４とヘッド部５２の４点の連結点が平行四辺形の頂点に位置して、鉛直な平面で上下に平行リンク運動する第２平行リンクアーム部５１ｂが構築される。
【００１８】
ロボット作業用ヘッド部５２は、略鉛直な矩形の取付板５４と、取付板５４の裏面４隅部に突設した自在継手５３と、取付板５４の前面に突設した自動作業機装着部５５を有する。取付板５４の裏面４隅の自在継手５３に４本の平行アーム５３ａ、５３ｂの先端部が連結されてリンク機構５０が構築される。第１昇降体２０と第２昇降体３０が同一高さにあるとき、同一長さの第１、第２平行リンクアーム部５１ａ、５１ｂが平行に対峙し、リンク機構５０が真上から見て平行四辺形の関係に保持されて、Ｘ−Ｙ方向に平行リンク運動する。
【００１９】
ヘッド部５２の自動作業機装着部５５に自動作業機、例えば一対のナットランナー５８が略鉛直にして着脱自在に装着される。一対の各ナットランナー５８は、図４に示すように所定の間隔Ｗ１で配列されて、鉛直な姿勢のままヘッド部５２と共にＸ方向、Ｙ方向、Ｚ方向に平行移動して、後述するような所望のねじ締め動作をする。一対のナットランナー５８の間隔Ｗ１は、例えば図７のワーク９の２点ＰａとＱａの最小的な間隔Ｗ１に設定される。この間隔は縮小拡大自在とされ、その最大間隔に対応させてヘッド部５２の最大幅Ｗ２が設定される。つまり、ヘッド部５２の幅Ｗ２は、大きくなるほどロボット１０の幅方向の設置スペースを大きくし、ロボット１０を大形重量物化することから、この幅Ｗ２はロボット１０が大形大重量とならないよう考慮して設定される。
【００２０】
第１昇降体２０を上下動させる第１駆動手段７０は、図２に示すように左右一対の支柱１１ａ、１１ｂの右側支柱の外側面にＺ方向に設置されたボールねじ７１と、ボールねじ７１を正逆回転させるモータ７２を有する。ボールねじ７１の一部にナット部材７３が螺装され、ボールねじ７１の上下両端部が軸受部材７４、７５で支柱１１ａに取付けられる。ナット部材７３は第１昇降体２０の支持板２１の外側端に一体に連結され、ボールねじ７１が非回転状態にあるときはナット部材７３が第１昇降体２０を支柱１１ａの任意の高さ位置に保持し、ボールねじ７１をモータ７２で正逆回転させるとナット部材７３と第１昇降体２０が一体となって支柱１１ａの前面側で上下動する。
【００２１】
第２昇降体３０を上下動させる第２駆動手段８０は、図１に示すように左右一対の支柱１１ａ、１１ｂの左側支柱の外側面にＺ方向に設置されたボールねじ８１と、ボールねじ８１を正逆回転させるモータ８２を有する。ボールねじ８１の一部にナット部材８３が螺装され、ボールねじ８１の上下両端部が軸受部材８４、８５で支柱１１ｂに取付けられる。ナット部材８３は第２昇降体３０の支持板３１の外側端に一体に連結され、ボールねじ８１が非回転状態にあるときはナット部材８３が第２昇降体３０を支柱１１ｂの任意の高さ位置に保持し、ボールねじ８１をモータ８２で正逆回転させるとナット部材８３と第２昇降体３０が一体となって支柱１１ｂの前面側で上下動する。
【００２２】
第３昇降体４０は、支柱１１ａのガイドレール１４の前面側を上下動する略鉛直でＸ方向に平行な支持板４１と、支持板４１の裏面両側に設置された複数のガイドローラ４２と、支持板４１の前面中央部に設置された１本のアーム連結用回転軸４３を有する。回転軸４３は、支持板４１の前面上下両端から前方に突設された軸受板４４、４５に水平方向に回転可能に連結される。回転軸４３の中央部に突設されたブラケットと第１平行リンクアーム部５１ａの下段の平行アーム５３ａの中央部に突設されたブラケットに１本の駆動アーム６０の両端部が上下方向に回転可能に連結される。駆動アーム６０と第１平行リンクアーム５１ａの２本の平行アーム５３ａは鉛直な平面に並んで、鉛直平面で上下に平行リンク運動する。
【００２３】
第３昇降体４０を上下動させる第３駆動手段９０が、左右一対の支柱１１ａ、１１ｂの間に設置される。図３に示すように、第３駆動手段９０は、一方の支柱１１ａの内側面、つまり、第１駆動手段７０と反対の側面に配設されるもので、支柱１１ａの内側面と平行に設置されたボールねじ９１と、ボールねじ９１を正逆回転させるモータ９２を有する。ボールねじ７１の一部にナット部材９３が螺装される。ナット部材９３は第３昇降体４０の支持板４１と一体で、ボールねじ９１が非回転状態にあるときはナット部材９３で第３昇降体４０が支柱１１ａに保持され、ボールねじ９１をモータ９２で正逆回転させるとナット部材９３と第３昇降体４０が支柱１１ａに沿って昇降する。
【００２４】
第３昇降体４０に、駆動アーム６０をＸ方向に回転揺動させる第４駆動手段１００が設置される。第４駆動手段１００は、第３昇降体４０の支持板４１の前面下端部に突設した軸受板４６の下面に固定したモータ１０１と、モータ１０１の回転出力軸と回転軸４３を一体に連結するコ字状の回転駆動枠１０２を有し、モータ１０１の回転力が回転駆動枠１０２を介して回転軸４３に直接に伝達されて、回転軸４３がＸ平方向に正逆回転する。モータ１０１で回転軸４３をＸ方向に正逆回転させることで、駆動アーム６０とこれに連結された第１平行リンクアーム部５１ａが同時にＸ方向に揺動回転し、この回転力がヘッド部５２を介して第２平行リンクアーム部５１ｂに伝達されて、リンク機構５０がＸ方向に揺動回転する。
【００２５】
鉛直なヘッド部５２の裏面左右上下の４箇所が左右一対の各平行リンクアーム部５１ａ、５１ｂの計４本の平行アーム５３ａ、５３ｂで支持され、第１平行リンクアーム部５１ａの平行アーム５３ａが下方から駆動アーム６０で補強されるように支持されるため、各アームの軽量化が実現され、ヘッド部５２の支持強度、剛性が常に高く確保されて、ヘッド部５２に一対のナットランナー５８を安定して取付けることができる。さらに、ヘッド部５２に取付けるナットランナー５８などから発生する反力が４本の平行アーム５３ａ、５３ｂと駆動アーム６０に分配されることで、ヘッド部５２を含むリンク機構５０の高剛性化が実現され、後述するような運転の高速化、安定化が実現される。
【００２６】
また、鉛直なヘッド部５２は鉛直な姿勢のまま前後左右上下に平行移動すると共に、後述するように第１昇降体２０と第２昇降体３０の高さを変位させることで水平方向に回転（θ回転）して水平方向の向きが１８０°未満の範囲で変位する。このようなヘッド部５２のθ変位は、一対のナットランナー５８でねじ締め作業を受けるワークの種類変更などに応じて行われる。
【００２７】
以上のアーム式ロボット１０は、第１〜第４駆動手段７０〜１００をコンピュータ制御によって同時に、或いは、異なる時間帯で独自に駆動させて、一対のナットランナー５８を略鉛直な姿勢のままＸ方向、Ｙ方向、Ｚ方向の上下左右前後に平行移動させる。一対のナットランナー５８は、例えば図５（Ａ）に示す製造組立ラインＬにおけるワーク９の各一対の２点Ｐ１、Ｑ１、…を順に移動して、２点同時のねじ締め動作を順に行う。或いは、図５（Ａ）に示す製造組立ラインＬにおけるワーク９の各一対の２点Ｐ３、Ｑ３、…を順に移動して、２点同時のねじ締め動作を順に行う。
【００２８】
図１〜図４の静止状態において、第１昇降体２０と第２昇降体３０が同一高さにあるとき、リンク機構５０は平面から見て平行四辺形を成し、水平方向に平行リンク運動可能な状態にある。この状態で第４駆動手段１００のモータ１０１だけを作動させて第１平行リンクアーム部５１ａをＸ方向に揺動回転させると、この回転力でリンク機構５０がＸ方向に平行リンク運動して左右に揺動回転し、鉛直なヘッド部５２と一対のナットランナー５８が同じ高さで左右に平行移動する。
【００２９】
また、図１〜図４の静止状態において、第１駆動手段７０と第２駆動手段８０を同時に駆動させて第１昇降体２０と第２昇降体３０を同時に同速で上昇させると、第１平行リンクアーム部５１ａの平行アーム５３ａが駆動アーム６０で下方に引っ張られてリンク機構５０がＺ方向で平行リンク運動し、ヘッド部５２と一対のナットランナー５８が支柱１１ａ、１１ｂに近付くようにＹ方向に平行移動する。逆に、第１駆動手段７０と第２駆動手段８０で第１昇降体２０と第２昇降体３０を同時に同速で下降させると、第１平行リンクアーム部５１ａの平行アーム５３ａが駆動アーム６０で突き上げられてリンク機構５０が平行リンク運動し、ヘッド部５２と一対のナットランナー５８が支柱１１ａ、１１ｂから遠ざかるようにＹ方向に平行移動する。この間、ヘッド部５２とナットランナー５８は鉛直で、かつ、Ｘ方向に平行な姿勢は変わらない。
【００３０】
また、図１〜図４の静止状態において、第３駆動手段９０だけを駆動させて第３昇降体４０だけを昇降させると、リンク機構５０が上下に平行リンク運動して、ヘッド部５２とナットランナー５８が鉛直姿勢のままＹ方向に平行移動する。
【００３１】
さらに、図１〜図４の静止状態において、第１〜第３駆動手段７０〜９０を同時に駆動させて第１〜第３昇降体２０〜４０を同時に同速度で昇降させると、リンク機構５０の全体が昇降する。この昇降の途中で第３昇降体４０の昇降だけを止めると、ヘッド部５２がＹ方向に平行移動を始める。このようなヘッド部５２の上下左右前後の平行移動は、通常のアーム式では２軸の関数演算をしないと直線運動をさせられないが、本発明の場合は関数演算しなくても直線運動をするため、ティーチングやプログラミングする場合に有利である。
【００３２】
以上の要領でヘッド部５２を平行移動させることで、図５（Ａ）に示すように、一対のナットランナー５８をワーク９の隣接する２点Ｐ１、Ｑ１の被ねじ締め部に移動させて２点同時のねじ締め動作させる。２点Ｐ１、Ｑ１でねじ締め動作の終了した一対のナットランナー５８を真上に上昇させてから、一対のナットランナー５８を次のねじ締めの２点Ｐ２、Ｑ２の真上に移動させる。第１〜第４駆動手段７０〜１００をコンピュータ制御することで、一対のナットランナー５８はワーク９の２点間を予め設定された最短距離で移動して、高能率でねじ締め動作を行う。
【００３３】
図５（Ｂ）は、ワーク９の被ねじ締め部である隣接する２点Ｐ３、Ｑ３の配列が図５（Ａ）と異なる場合を示している。２点Ｐ３、Ｑ３がＸ方向に定間隔で隣接し、次にねじ締めされる２点Ｐ４、Ｑ４がＸ方向と角度θを成す方向に定間隔で隣接している。図５（Ａ）の要領で２点Ｐ３、Ｑ３を一対のナットランナー５８でねじ締めした後、ヘッド部５２をＸ方向と角度θを成す方向に回転させて次の２点Ｐ４、Ｑ４のねじ締め動作に向かわせる。ヘッド部５２のθ回転は、第１昇降体２０と第２昇降体３０の高さの差を変えることで実行される。例えば、図１の静止状態において、第１昇降体２０を静止させて第２昇降体３０だけを上昇させると、第２平行リンクアーム部５１ｂだけが鉛直平面で平行リンク運動してヘッド部５２に引寄せるように外力を作用させ、この作用で図４の鎖線で示すようにヘッド部５２が鉛直姿勢のまま水平方向に角度θで回転する。この回転角度θをワーク９の次の２点Ｐ４、Ｑ４の角度にすることで、２点Ｐ４、Ｑ４の同時ねじ締めが実行される。このようなねじ締めされる２点の角度は任意に設定でき、より多様なねじ締めパターンを持つ種類のワークのねじ締めができて、ロボット１０の汎用性を高める。
【００３４】
図５（Ａ）、（Ｂ）で分かるように、リンク機構５０の各平行リンクアーム部５１ａ、５１ｂはアーム長さ方向に変位するが、Ｘ方向のアーム幅方向にく字状に屈曲するといった変位をしないため、ロボット１０の床上設置上に必要とされる幅方向スペースＳ２は、概ねワーク９の幅で決まる必要最小限のスペースで済み、ロボットの設置スペースの縮小化が図れる。また、ヘッド部５２を支持する各平行リンクアーム部５１ａ、５１ｂの平行アーム５３ａ、５３ｂを駆動アーム６０で補強した構造のため、各アームに構造簡単な軽量物が使用できて、各アームの上下左右前後の動きを速くすることが容易に可能となり、一対のナットランナー５８によるねじ締め動作をより高能率で行うことができる。
【００３５】
また、ロボット１０に対するヘッド部５２の左右横移動は、支柱１１ａ、１１ｂを含むロボット全体を横に回転させる、又は、支柱１１ａ、１１ｂに支持された昇降体２０、３０のようなアーム支持用台座部を横に回転させることでも可能であるが、このような重量物を回転させずに軽量なアームだけを回転させることで、各アームの速い動きが実現でき、また、アーム回転駆動源である第４駆動手段１００に構造簡単で小形、安価なものが適用できる。
【００３６】
また、１台のヘッド部５２を２台の第１平行リンクアーム部５１ａ、５１ｂで支持するために、ヘッド部５２を含むリンク機構５０を高剛性構造体とすることが容易になり、ヘッド部５２に単機のみならず複数機の自動作業機を搭載させても剛性的に問題なく、汎用性に優れたロボットが構築できる。上記実施の形態のように、１台のヘッド部５２に一対のナットランナー５８を搭載して、ワークに２点ずつ多数点設けられた被ねじ締め部を２点ずつ同時にねじ締めすることで、多数点全てのねじ締めが短時間で行なえるようになる。
【００３７】
また、ヘッド部５２は、自動作業機を支持するだけの構造でよく、水平方向の向きを変える駆動源などが不要となるため、ヘッド部５２におけるイナーシャを極端に小さくしてヘッド部５２自体を構造簡単、軽量なものにすることができ、なお一層の高速運転が可能となる。
【００３８】
なお、本発明は、上記実施の形態に限らず、例えば、共通の支柱に配設する第１昇降体と第３昇降体の位置関係を上下逆にして、下部の第１昇降体から延びる平行リンクアーム部に上方から第３昇降体から延びる駆動アームを連結するようにしてもよい。
【００３９】
【発明の効果】
本発明によれば、自動作業機を搭載するヘッド部を、鉛直平面で平行リンク運動する第１平行リンクアーム部と第２平行リンクアーム部の先端部で支持し、各平行リンクアーム部の基端部を鉛直な定軌道に沿って独自に昇降させるようにしたので、ヘッド部を含むリンク機構の剛性が高く安定して、ヘッド部に支持される単数或いは複数の自動作業機の支持強度が増し、高速移動による高速作業が可能となる。かつ、各平行リンクアーム部の基端部の高さを任意に変位させることでヘッド部の水平方向の向きが任意に調整できて、ヘッド部に支持された自動作業機を専用の回転軸で回転させることなく任意に角度変更でき、また、ヘッド部に複数の自動作業機を設置した場合には、複数の自動作業機の配列角度を任意に変更することが容易にできて、多様な複数種類の自動作業機に対応できる汎用性に優れたアーム式ロボットが提供できる。
【００４０】
また、平行リンクアーム部を構成する平行アームやこれを左右揺動させる駆動アームの各アームが同一の略鉛直な平面で上下揺動するため、リンク機構が幅方向に屈曲せずにロボットの幅方向スペースが必要最小限まで縮小できて、複数台のロボットを接近させて省スペースで併設することが可能となる。さらに、平行リンクアーム部の各アームを駆動アームで補強することができて、各アームに構造簡単で軽量なものが適用でき、高速運転が容易になる。
【００４１】
また、定軌道を前面に構成する左右一対の支柱の間と両側に第１〜第３駆動手段を配設することで、ロボット幅方向スペースの増大が抑制できて、高剛性のロボットを省スペースで設置したり、複数台のロボットを接近させて省スペースで併設することが容易になる。
【図面の簡単な説明】
【図１】本発明の実施の形態を示すアーム式ロボットの斜視図である。
【図２】図１のロボットの角度を変えた方向からの斜視図である。
【図３】図１のロボットの正面図である。
【図４】図１のロボットの平面図である。
【図５】（Ａ），（Ｂ）は図１のロボットとワークの概要を示す平面図である。
【図６】従来のアーム式ロボットの斜視図である。
【図７】図６のアーム式ロボットとワークの概要を示す平面図である。
【符号の説明】
１０アーム式ロボット
１１ａ支柱
１１ｂ支柱
１４ガイドレール
２０第１昇降体
２４アーム連結用回転軸
３０第２昇降体
３４アーム連結用回転軸
４０第３昇降体
４３アーム連結用回転軸
５０リンク機構
５１ａ第１平行リンクアーム部
５１ｂ第２平行リンクアーム部
５２ヘッド部
５３ａ平行アーム
５３ｂ平行アーム
５５自動作業機装着部
５８自動作業機、ナットランナー
６０駆動アーム
７０第１駆動手段
７２モータ
８０第２駆動手段
８２モータ
９０第３駆動手段
９２モータ
１００第４駆動手段
１０１モータ
１０２回転駆動枠[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an arm type robot that freely moves an automatic working machine such as a nut runner in both a horizontal orthogonal two directions (XY direction) and a substantially vertical vertical direction (Z direction).
[0002]
[Prior art]
Common robots that freely move nut runners used in automobile manufacturing and assembly lines horizontally and vertically include orthogonal robots and SCARA robots. Since the former orthogonal robot uses a table that moves in two horizontal orthogonal directions, a large installation space is required in the horizontal width direction, and there are many space restrictions in installation on the production assembly line. Also, in the case of the latter SCARA-type arm type robot, a large installation space is required in the width direction as will be described later.
[0003]
FIG. 6 shows a specific example of a SCARA-type arm robot (for example, see Patent Document 1). The robot 1 can rotate the rear end portion of the first horizontal arm 3 to the upper end portion of the substantially vertical main shaft 2. The rear end of the second horizontal arm 4 is rotatably connected to the front end of the first horizontal arm 3, and the vertical shaft 6 is connected to the vertical shaft 6 so as to move up and down by the bearing 5 at the front end of the second horizontal arm 4. is doing. For example, a nut runner 7 of an automatic working machine is fixed to the vertical shaft 6, and each horizontal arm 3, 4 pivots independently in the horizontal direction, so that the robot working head unit 8 including the bearing 5 and the vertical shaft 6 The nut runner 7 moves in the horizontal direction. The workpiece 9 on the transport body along the production assembly line L shown in FIG. 7 has a plurality of screw tightening portions indicated by points P and Q in the drawing, and the nut runner is directly above these screw tightening portions. The 1st horizontal arm 3 and the 2nd horizontal arm 4 carry out a turning motion independently so that 7 may move in order.
[0004]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 2000-141257 (FIGS. 3 and 5)
[0005]
[Problems to be solved by the invention]
As shown by a chain line in FIG. 7, when the first horizontal arm 3 and the second horizontal arm 4 are, for example, in a straight connection state, the head portion 8 moves to the most distant point Pb on the work 9 and is screwed. When the tightening operation is performed, and the first horizontal arm 3 and the second horizontal arm 4 are bent in a horizontal shape in the horizontal direction and the head portion 8 moves to the nearest one point Pa, the screw tightening operation is performed. 6 requires a large width direction space S1 in which the horizontal arms 3 and 4 bend and protrude on both the left and right sides in front of the robot, and this width direction space S1 is an arm type robot. The installation space on the floor of 1 was increased. Further, when a plurality of arm-type robots 1 are provided on the floor, the distance between a pair of adjacent robots needs to be at least twice the width direction space S1, and a plurality of robots are provided in a space-saving manner. Is difficult.
[0006]
Further, the horizontal arms 3 and 4 and the head unit 8 of the arm type robot 1 tend to be large heavy objects having a large width, thickness and diameter due to their required functions, so that they move quickly. It is difficult to let In particular, the head portion 8 has a large-diameter structure such as a power source that moves the vertical shaft 6 up and down. For example, two points Pa and Qa that are close to each other at a predetermined minimum interval W1 on the workpiece 9 shown in FIG. When trying to screw the parts simultaneously with two identical arm type robots, the head parts of the two robots may interfere with each other and may not be screwed at the same time. Therefore, when one point Pa is screwed with one robot, the head portion 8 is moved and screwed to the other one point Qa closest to the one point Pa, so that a pair of approaching points Pa, It is difficult to improve the work of tightening Qa. Although not shown, it is possible to improve workability by arranging a pair of nut runners in one head portion and screwing the two points Pa and Qa at the same time. The weight and outer diameter of the head portion are doubled for the runner, and the horizontal arm has a large rigid structure with high rigidity, making it difficult to operate at high speed.
[0007]
The purpose of the present invention is to make it easy to reduce the installation space, enable fast movement by reducing the size and weight of the arm, and freely adapting to changing the type of work to be processed by an automatic work machine Is to provide a robot.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention includes a pair of left and right first lifting bodies 20 and second lifting bodies 30 that independently move up and down substantially vertical parallel fixed tracks, and fixed tracks on which the first lifting body 20 moves up and down. A third elevating body 40 that moves up and down separately from the first elevating body, a rear end portion is connected to the first elevating body 20 so as to be rotatable in the vertical and horizontal directions, and a tip portion is rotated in the vertical and horizontal directions to the robot work head portion 52. The first parallel link arm portion 51a having a plurality of parallel arms 53a that are connected to each other and move in parallel up and down on a substantially vertical plane with the rear end portion as a base point, and the rear end portion of the second elevating body 30 has a rear end portion. A plurality of parallel arms 53b that are coupled to be vertically rotatable in the vertical and horizontal directions, the tip portions thereof are rotatably coupled to the head portion 52 in the vertical and horizontal directions, and perform parallel link motions in a vertical plane with the rear end portion as a base point. And a second parallel link arm portion 51b provided with A rear end portion is connected to the link mechanism 50 and the third elevating body 40 so as to be rotatable in the vertical and horizontal directions, and a front end portion is connected to the first parallel link arm portion 51a so as to be rotatable in the vertical direction. A driving arm 60 that swings up and down on a substantially vertical plane in which the part 51a moves in parallel, and first to third driving means that are installed on the fixed track and independently raise and lower the first to third lifting bodies 20 to 40. 70 to 90 and fourth drive means 100 installed on the third elevating body 40 to rotate and swing the drive arm 60 in the horizontal direction (invention of claim 1).
[0009]
Here, the substantially vertical parallel fixed track is composed of a pair of left and right support columns 11a and 11b, a guide rail fixed to the support column, and a guide groove formed in the similar support column. A pair of left and right bodies of the first elevating body 20 and the second elevating body 30 move up and down in the same direction or in the opposite direction along this parallel fixed track, or one of them stops and only the other moves up and down. The 1st raising / lowering body 20 and the 3rd raising / lowering body 40 are divided into the upper part and the lower part of the same fixed track, and are raised / lowered independently. The parallel arms 53a of the first parallel link arm portion 51a are two or more straight steel arms of the same length that move in parallel links up and down along a substantially vertical plane. The rear end portion of the arm 53a is connected to the first elevating body 20, and the front end portion is connected to the robot working head portion 52, thereby constructing a first parallel link arm portion 51a that forms a parallelogram in the vertical plane. . Similarly, the second parallel link arm portion 51b includes a plurality of parallel arms 53b. The pair of left and right first and second parallel link arm portions 51a and 51b independently perform a parallel link movement on a vertical plane, and the head portion 52 moves back and forth, right and left and up and down while maintaining a vertical posture. Since the head portion 52 is supported by the pair of parallel link arm portions 51a and 51b, the head portion 52 maintains stable high rigidity and stably holds an automatic working machine such as a single machine or a plurality of nut runners on the head section 52. . By moving the first lifting body 20 and the second lifting body 30 up and down independently and displacing the relative heights of them, the head unit 52 rotates in the horizontal direction to change the horizontal direction of the automatic work machine. Displace freely.
[0010]
Further, the drive arm 60 swings and rotates the first parallel link arm portion 51a horizontally in the horizontal direction, and the second parallel link arm portion 51b also swings and rotates integrally with this swinging rotational force to move the head portion 52. Move horizontally left and right. The drive arm 60 swings and rotates the link mechanism 50 and reinforces the link mechanism 50 to enable application of a simple and lightweight structure to each arm. Servo motors and cylinders can be used as the drive sources for the first to third drive means 70 to 90 and the fourth drive means 100.
[0011]
In the present invention, the parallel fixed orbits are arranged on the front surfaces of a pair of left and right support columns 11a and 11b fixed substantially vertically, and the first between the pair of left and right support columns 11a and 11b and the outer surface of each support column. -The 3rd drive means 70-90 can be distributed and arrange | positioned (invention of Claim 2). By causing the pair of left and right support columns 11a and 11b to face each other at a predetermined interval, for example, the third drive unit 90 is disposed between the columns, and the first drive unit 70 and the second drive unit 80 are disposed on the outer surface of both columns. The installation space in the width direction of the entire robot can be reduced to a minimum.
[0012]
Further, in the present invention, the robot working head unit 52 can be structured to detachably support a plurality of automatic working machines in a predetermined arrangement in the horizontal direction (invention of claim 3). In this case, the head unit 52 has a general-purpose structure that detachably supports automatic work machines such as nut runners, screw-fastening power tools, clip stand tools, and visual inspection equipment, so that various automatic work machines can be replaced. Robots can provide. Further, by installing a plurality of automatic working machines on one head unit 52 and operating each automatic working machine at the same time, workability such as screw tightening can be improved.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
[0014]
The arm type robot 10 shown in FIGS. 1 and 2 includes a pair of left and right support columns 11a and 11b fixed substantially vertically on a floor, and a first elevating body 20 that independently moves up and down on the front surfaces of the support columns 11a and 11b. A second elevating body 30, a third elevating body 40 elevating separately from the first elevating body 20 along one column 11 a on which the first elevating body 20 moves up and down, and a first extending from the first elevating body 20 to the front. A link mechanism 50 including one common link arm 51a and one common robot work head 52 connected to the respective distal ends of the second parallel link arm 51b extending forward from the second elevating body 30; , A driving arm 60 extending forward from the third lifting body 30, first to third driving means 70 to 90 for independently lifting and lowering the first to third lifting bodies 20 to 40, and the driving arm 60 in the horizontal direction. Fourth drive means 100 for rotating and swinging Provided.
[0015]
The pair of left and right support columns 11a and 11b are prisms that face each other at regular intervals in parallel, and are fixed on the floor by a pedestal 12 fixed to the lower end, and the upper ends of each are connected by a connecting body 13. A horizontal direction in which the pair of columns 11a and 11b are arranged is defined as an X direction, a horizontal direction orthogonal to the X direction is defined as a Y direction, and a vertical direction is defined as a Z direction. Each of the first elevating body 20 and the second elevating body 30 is a substantially vertical rectangular plate parallel to the X direction, and is normally juxtaposed at substantially the same height. A guide rail 14 is arranged in the Z direction on the front surface of each of the pair of support pillars 11a and 11b. A first lifting body 20 is connected to an upper area of the guide rail 14 of one support pillar 11a so as to be movable up and down, and a lower area has a first 3 The elevating body 40 is connected to be movable up and down. The guide rail 14 of the other support column 11b is installed only in the upper region of the support column 11b, and the second elevating body 30 is connected to the guide rail 14 so as to be movable up and down. Moreover, the some sensor 15 which detects the up-and-down position of the 1st-3rd raising / lowering bodies 20-40 is installed in each support | pillar 11a, 11b as needed.
[0016]
The first elevating body 20 includes a substantially vertical support plate 21 that moves up and down the front side of the guide rail 14 of the column 11a, a plurality of guide rollers 22 installed in the Z direction on both sides of the back surface of the support plate 21, and a support plate. 21 has a single vertical arm connecting rotary shaft 24 disposed in the center of the front surface. The rotary shaft 24 is connected to a bearing plate 23 protruding forward from both upper and lower ends of the front surface of the support plate 21 so as to be rotatable in the horizontal direction. Each guide roller 22 on both sides of the back surface of the support plate 21 sandwiches the corresponding guide rails 14 from both side surfaces to guide the vertical movement of the support plate 21. The rear end portions of two parallel parallel arms 53a are connected to a pair of upper and lower brackets 25 projecting from the upper and lower ends of the rotating shaft 24 via pins so as to be rotatable in the vertical direction. The two parallel arms 53a are rigid arms having the same length, and are connected to two upper and lower portions of the back surface of the head portion 52, each of which has a substantially vertical flat plate so as to be rotatable in the vertical and horizontal directions. A first parallel link arm portion 51a that moves in parallel up and down on a vertical plane is located at the apex of the parallelogram, with the connection point of the four parallel arms 53a, the rotary shaft 24, and the head portion 52 at the top of the parallelogram. Is built.
[0017]
The second elevating body 30 may have the same structure as the first elevating body 20, and a substantially vertical support plate 31 that moves up and down the front side of the guide rail 14 of the support 11 b and both sides of the back surface of the support plate 21 in the Z direction. And a plurality of guide rollers 32 installed at the center of the front surface of the support plate 31 and a single rotary shaft 34 for arm connection. The upper and lower ends of the rotating shaft 34 are coupled to a bearing plate 33 protruding forward from both upper and lower ends of the front surface of the support plate 31 so as to be rotatable in the horizontal direction. The rear end portions of two parallel parallel arms 53b are connected to a pair of upper and lower brackets 35 projecting from the upper and lower ends of the rotation shaft 34 via pins so as to be rotatable in the vertical direction. The two parallel arms 53b are rigid arms having the same length as the parallel arm 53a, and their respective tip portions are connected to two upper and lower portions of the back surface of the head portion 52 so as to be rotatable in the vertical and horizontal directions. A connecting point of the four parallel arms 53b, the rotating shaft 34, and the head part 52 is located at the apex of the parallelogram, and a second parallel link arm part 51b that moves in parallel up and down on a vertical plane is provided. Built.
[0018]
The robot work head unit 52 includes a substantially vertical rectangular mounting plate 54, a universal joint 53 projecting from the four corners of the back surface of the mounting plate 54, and an automatic work machine mounting unit 55 projecting from the front surface of the mounting plate 54. Have The link mechanism 50 is constructed by connecting the front ends of the four parallel arms 53a and 53b to the universal joints 53 at the four corners of the back surface of the mounting plate 54. When the first lifting body 20 and the second lifting body 30 are at the same height, the first and second parallel link arm portions 51a and 51b having the same length face each other in parallel, and the link mechanism 50 is viewed from directly above. The parallel link is moved in the XY direction while being held in a parallelogram relationship.
[0019]
An automatic work machine, for example, a pair of nut runners 58, is attached to the automatic work machine mounting part 55 of the head part 52 in a substantially vertical manner so as to be detachable. The pair of nut runners 58 are arranged at a predetermined interval W1 as shown in FIG. 4 and are translated in the X direction, the Y direction, and the Z direction together with the head portion 52 in a vertical posture, as will be described later. A desired screw tightening operation is performed. The interval W1 between the pair of nut runners 58 is set to, for example, the minimum interval W1 between the two points Pa and Qa of the workpiece 9 in FIG. This interval can be reduced and enlarged, and the maximum width W2 of the head portion 52 is set corresponding to the maximum interval. That is, the larger the width W2 of the head portion 52 is, the larger the installation space in the width direction of the robot 10 is, and the robot 10 is made large and heavy. Therefore, the width W2 is considered so that the robot 10 does not become large and heavy. Is set.
[0020]
As shown in FIG. 2, the first driving means 70 that moves the first lifting body 20 up and down includes a ball screw 71 installed in the Z direction on the outer surface of the right column of the pair of left and right columns 11 a and 11 b, and the ball screw 71. Has a motor 72 for forward and reverse rotation. A nut member 73 is screwed to a part of the ball screw 71, and both upper and lower ends of the ball screw 71 are attached to the support 11a by bearing members 74 and 75. The nut member 73 is integrally connected to the outer end of the support plate 21 of the first elevating body 20, and when the ball screw 71 is in a non-rotating state, the nut member 73 moves the first elevating body 20 to an arbitrary height of the column 11a. When the ball screw 71 is rotated in the forward and reverse directions by the motor 72 while being held in position, the nut member 73 and the first elevating body 20 move up and down on the front side of the column 11a.
[0021]
As shown in FIG. 1, the second driving means 80 for moving the second lifting body 30 up and down includes a ball screw 81 installed in the Z direction on the outer surface of the left column of the pair of left and right columns 11a and 11b, and a ball screw 81. Has a motor 82 for forward and reverse rotation. A nut member 83 is screwed to a part of the ball screw 81, and both upper and lower ends of the ball screw 81 are attached to the column 11b by bearing members 84 and 85. The nut member 83 is integrally connected to the outer end of the support plate 31 of the second elevating body 30, and when the ball screw 81 is in a non-rotating state, the nut member 83 moves the second elevating body 30 to an arbitrary height of the column 11b. When the ball screw 81 is rotated in the forward and reverse directions by the motor 82 while being held in position, the nut member 83 and the second elevating body 30 are integrally moved up and down on the front side of the column 11b.
[0022]
The third elevating body 40 includes a substantially vertical support plate 41 that moves up and down on the front side of the guide rail 14 of the support column 11a, and a plurality of guide rollers 42 that are installed on both sides of the back surface of the support plate 41. It has one arm connecting rotary shaft 43 installed in the center of the front surface of the support plate 41. The rotating shaft 43 is connected to bearing plates 44 and 45 projecting forward from upper and lower ends of the front surface of the support plate 41 so as to be rotatable in the horizontal direction. Both ends of one drive arm 60 rotate vertically in a bracket projecting at the center of the rotating shaft 43 and a bracket projecting in the center of the lower parallel arm 53a of the first parallel link arm 51a. Connected as possible. The two parallel arms 53a of the drive arm 60 and the first parallel link arm 51a are arranged in a vertical plane and move in parallel links up and down on the vertical plane.
[0023]
Third driving means 90 for moving the third elevating body 40 up and down is installed between the pair of left and right columns 11a and 11b. As shown in FIG. 3, the third driving means 90 is disposed on the inner surface of one of the columns 11a, that is, on the side opposite to the first driving device 70, and is installed in parallel with the inner surface of the column 11a. And a motor 92 for rotating the ball screw 91 forward and backward. A nut member 93 is screwed to a part of the ball screw 71. The nut member 93 is integrated with the support plate 41 of the third elevating body 40. When the ball screw 91 is in a non-rotating state, the third elevating body 40 is held by the support 11a by the nut member 93, and the ball screw 91 is moved to the motor 92. Then, the nut member 93 and the third elevating body 40 are moved up and down along the column 11a.
[0024]
A fourth driving means 100 for rotating and swinging the driving arm 60 in the X direction is installed on the third elevating body 40. The fourth driving means 100 integrally connects the motor 101 fixed to the lower surface of the bearing plate 46 projecting from the lower end of the front surface of the support plate 41 of the third elevating body 40, the rotation output shaft of the motor 101, and the rotation shaft 43. The rotation force of the motor 101 is directly transmitted to the rotation shaft 43 via the rotation drive frame 102, and the rotation shaft 43 rotates forward and backward in the X plane direction. By rotating the rotating shaft 43 forward and backward in the X direction by the motor 101, the drive arm 60 and the first parallel link arm portion 51 a connected thereto are simultaneously swung and rotated in the X direction. Is transmitted to the second parallel link arm portion 51b via the link mechanism 50, and the link mechanism 50 swings and rotates in the X direction.
[0025]
Four positions on the back, left, right, top and bottom of the vertical head portion 52 are supported by a total of four parallel arms 53a, 53b, which are a pair of left and right parallel link arms 51a, 51b. The parallel arms 53a of the first parallel link arm 51a Since it is supported so as to be reinforced by the drive arm 60 from below, the weight of each arm is reduced, and the support strength and rigidity of the head portion 52 are always ensured high, and a pair of nut runners 58 is attached to the head portion 52. Can be installed stably. Further, the reaction force generated from the nut runner 58 attached to the head portion 52 is distributed to the four parallel arms 53a and 53b and the drive arm 60, thereby realizing high rigidity of the link mechanism 50 including the head portion 52. Thus, speeding up and stabilization of the operation as described later are realized.
[0026]
In addition, the vertical head unit 52 translates horizontally in the vertical direction with the vertical posture, and rotates in the horizontal direction by displacing the heights of the first lifting body 20 and the second lifting body 30 as described later ( θ direction) and the horizontal direction is displaced within a range of less than 180 °. Such θ displacement of the head portion 52 is performed in accordance with a change in the type of a workpiece subjected to a screw tightening operation by the pair of nut runners 58.
[0027]
The above arm type robot 10 drives the first to fourth driving means 70 to 100 at the same time or independently in different time zones by computer control so that the pair of nut runners 58 remains in a substantially vertical posture in the X direction. , Y direction and Z direction are moved up and down, left and right and back and forth. The pair of nut runners 58 sequentially moves the pair of two points P1, Q1,... Of the workpiece 9 in the manufacturing assembly line L shown in FIG. Alternatively, each pair of two points P3, Q3,... Of the workpiece 9 in the manufacturing assembly line L shown in FIG.
[0028]
1 to 4, when the first lifting body 20 and the second lifting body 30 are at the same height, the link mechanism 50 forms a parallelogram when viewed from the plane, and the parallel link motion in the horizontal direction. It is in a possible state. In this state, when only the motor 101 of the fourth driving means 100 is operated to swing and rotate the first parallel link arm portion 51a in the X direction, the link mechanism 50 moves in a parallel link direction in the X direction by this rotational force. And the vertical head portion 52 and the pair of nut runners 58 are translated to the left and right at the same height.
[0029]
1 to 4, when the first driving means 70 and the second driving means 80 are simultaneously driven to raise the first elevating body 20 and the second elevating body 30 at the same speed simultaneously, The parallel arm 53a of the parallel link arm portion 51a is pulled downward by the drive arm 60 so that the link mechanism 50 performs a parallel link movement in the Z direction, and the head portion 52 and the pair of nut runners 58 approach the support columns 11a and 11b. Translate in the direction. Conversely, when the first elevating body 20 and the second elevating body 30 are simultaneously lowered at the same speed by the first driving means 70 and the second driving means 80, the parallel arm 53a of the first parallel link arm portion 51a is moved to the driving arm 60. Then, the link mechanism 50 moves in a parallel link, and the head portion 52 and the pair of nut runners 58 are translated in the Y direction so as to move away from the columns 11a and 11b. During this time, the head portion 52 and the nut runner 58 are vertical and the posture parallel to the X direction does not change.
[0030]
1 to 4, when only the third driving means 90 is driven and only the third elevating body 40 is moved up and down, the link mechanism 50 moves up and down in parallel to move the head portion 52 and the nut. The runner 58 translates in the Y direction while maintaining a vertical posture.
[0031]
Furthermore, when the first to third driving means 70 to 90 are simultaneously driven and the first to third lifting bodies 20 to 40 are simultaneously lifted at the same speed in the stationary state of FIGS. The whole goes up and down. If only raising / lowering of the 3rd raising / lowering body 40 is stopped in the middle of this raising / lowering, the head part 52 will start parallel translation to a Y direction. Such parallel movement of the head portion 52 up and down, left and right, and back and forth is not allowed to move linearly unless a biaxial function is calculated in the normal arm type, but in the present invention, linear movement is not required even if a function is not calculated. Therefore, it is advantageous when teaching or programming.
[0032]
As shown in FIG. 5 (A), the pair of nut runners 58 are moved to the screwed portions at the two points P1 and Q1 adjacent to the workpiece 9 by moving the head portion 52 in parallel as described above. The screw tightening operation is performed at the same time. The pair of nut runners 58 that have finished the screw tightening operation at the two points P1 and Q1 are raised directly above, and then the pair of nut runners 58 are moved right above the two points P2 and Q2 of the next screw tightening. By performing computer control of the first to fourth driving means 70 to 100, the pair of nut runners 58 moves between two points of the work 9 at a preset shortest distance, and performs a screwing operation with high efficiency.
[0033]
FIG. 5B shows a case where the arrangement of two adjacent points P3 and Q3, which are the screwed portions of the workpiece 9, is different from that in FIG. The two points P3 and Q3 are adjacent to each other in the X direction at regular intervals, and the two points P4 and Q4 to be screwed next are adjacent to each other in the direction that forms an angle θ with the X direction at regular intervals. After screwing the two points P3 and Q3 with a pair of nut runners 58 in the manner of FIG. 5A, the head 52 is rotated in a direction that forms an angle θ with the X direction, and the next two points P4 and Q4 are screwed. Direct to tightening operation. The θ rotation of the head unit 52 is executed by changing the height difference between the first lifting body 20 and the second lifting body 30. For example, in the stationary state of FIG. 1, when the first elevating body 20 is stopped and only the second elevating body 30 is raised, only the second parallel link arm portion 51 b moves in parallel on the vertical plane and moves to the head portion 52. An external force is applied so as to be attracted, and this action rotates the head portion 52 in the horizontal direction at an angle θ as shown by the chain line in FIG. By setting the rotation angle θ to the angle of the next two points P4 and Q4 of the workpiece 9, simultaneous screw tightening of the two points P4 and Q4 is executed. The angles of the two points to be screwed can be arbitrarily set, and the types of workpieces having more various screwing patterns can be screwed, so that the versatility of the robot 10 is enhanced.
[0034]
As can be seen from FIGS. 5A and 5B, each of the parallel link arm portions 51a and 51b of the link mechanism 50 is displaced in the arm length direction, but is bent in a square shape in the arm width direction in the X direction. Since the displacement is not caused, the width direction space S2 required for the installation on the floor of the robot 10 may be a minimum necessary space determined by the width of the workpiece 9, and the installation space for the robot can be reduced. In addition, since the parallel arms 53a and 53b of the parallel link arm portions 51a and 51b that support the head portion 52 are reinforced by the drive arm 60, a light structure with a simple structure can be used for each arm. It is possible to easily move the left and right and the front and rear, and the screw tightening operation by the pair of nut runners 58 can be performed with higher efficiency.
[0035]
Further, the horizontal movement of the head unit 52 with respect to the robot 10 causes the entire robot including the support columns 11a and 11b to rotate horizontally, or an arm support base such as the lifting bodies 20 and 30 supported by the support columns 11a and 11b. It is also possible to rotate the part sideways, but by rotating only lightweight arms without rotating such heavy objects, each arm can be moved quickly, and it is an arm rotation drive source The fourth driving means 100 can be applied with a simple structure, a small size, and a low price.
[0036]
In addition, since one head portion 52 is supported by the two first parallel link arm portions 51a and 51b, it is easy to make the link mechanism 50 including the head portion 52 a highly rigid structure. Even if a single machine or a plurality of automatic working machines are mounted on 52, there is no problem in rigidity, and a robot having excellent versatility can be constructed. As in the above embodiment, by mounting a pair of nut runners 58 on one head portion 52 and screwing the screw tightened portions provided at multiple points on the workpiece two points at a time, All of the multiple points can be tightened in a short time.
[0037]
In addition, the head unit 52 may have a structure that only supports the automatic working machine, and a drive source that changes the horizontal direction is not necessary. Therefore, the inertia in the head unit 52 is extremely reduced to reduce the head unit 52 itself. The structure can be simple and lightweight, and even higher speed operation is possible.
[0038]
The present invention is not limited to the above-described embodiment. For example, the first lift body and the third lift body disposed on a common support column are turned upside down so that the parallelism extends from the lower first lift body. You may make it connect the drive arm extended from a 3rd raising / lowering body from upper direction to a link arm part.
[0039]
【The invention's effect】
According to the present invention, the head unit on which the automatic working machine is mounted is supported by the front ends of the first parallel link arm unit and the second parallel link arm unit that perform parallel link movement in the vertical plane, and the base of each parallel link arm unit is supported. Since the end part is independently raised and lowered along a vertical fixed track, the rigidity of the link mechanism including the head part is high and stable, and the support strength of one or more automatic work machines supported by the head part is high. In addition, high-speed work by high-speed movement becomes possible. In addition, the horizontal direction of the head can be adjusted arbitrarily by arbitrarily displacing the height of the base end of each parallel link arm, and the automatic work machine supported by the head can be adjusted with a dedicated rotating shaft. The angle can be arbitrarily changed without rotating, and when a plurality of automatic working machines are installed on the head, it is easy to arbitrarily change the array angle of the plurality of automatic working machines. We can provide an arm-type robot with excellent versatility that can be used for various types of automatic work machines.
[0040]
In addition, each arm of the parallel arm constituting the parallel link arm portion and the drive arm that swings the left and right of the parallel link arm swings up and down on the same substantially vertical plane, so the link mechanism does not bend in the width direction and the width of the robot The direction space can be reduced to the minimum necessary, and a plurality of robots can be brought close to each other to save space. Furthermore, each arm of the parallel link arm portion can be reinforced with a drive arm, and a simple and lightweight structure can be applied to each arm, facilitating high-speed operation.
[0041]
In addition, by arranging the first to third drive means between the pair of left and right struts that constitute the fixed track on the front and on both sides, the increase in space in the robot width direction can be suppressed, saving space for high-rigidity robots. It is easy to install in a small space, or to install multiple robots close together to save space.
[Brief description of the drawings]
FIG. 1 is a perspective view of an arm type robot showing an embodiment of the present invention.
FIG. 2 is a perspective view from a direction in which the angle of the robot of FIG. 1 is changed.
FIG. 3 is a front view of the robot of FIG. 1;
4 is a plan view of the robot of FIG. 1. FIG.
5A and 5B are plan views showing an outline of the robot and workpiece in FIG.
FIG. 6 is a perspective view of a conventional arm type robot.
7 is a plan view showing an outline of the arm type robot and the work shown in FIG. 6;
[Explanation of symbols]
10 Arm type robot
11a prop
11b Prop
14 Guide rail
20 First lifting body
24 Rotating shaft for arm connection
30 Second lifting body
34 Rotating shaft for arm connection
40 Third lifting body
43 Rotating shaft for arm connection
50 Link mechanism
51a 1st parallel link arm part
51b Second parallel link arm
52 Head
53a Parallel arm
53b Parallel arm
55 Automatic working machine mounting part
58 Automatic working machines, nut runners
60 Drive arm
70 1st drive means
72 motor
80 Second drive means
82 motor
90 Third drive means
92 Motor
100 Fourth driving means
101 motor
102 Rotation drive frame

Claims

略鉛直な並列の定軌道を独自に昇降する左右一組の第１昇降体及び第２昇降体と、
前記第１昇降体が昇降する定軌道を第１昇降体と別に昇降する第３昇降体と、
前記第１昇降体に後端部が上下左右方向に回転可能に連結され、先端部がロボット作業用ヘッド部に上下左右方向に回転可能に連結されて、後端部を基点に略鉛直な平面で上下に平行リンク運動する複数の平行アームを備えた第１平行リンクアーム部と、前記第２昇降体に後端部が上下左右方向に回転可能に連結され、先端部が前記ヘッド部に上下左右方向に回転可能に連結されて、後端部を基点に略鉛直な平面で上下に平行リンク運動する複数の平行アームを備えた第２平行リンクアーム部とを有するリンク機構と、
前記第３昇降体に後端部が上下左右方向に回転可能に連結され、先端部が前記第１平行リンクアーム部に上下方向に回転可能に連結されて第１平行リンクアーム部が平行リンク運動する略鉛直な平面で上下揺動する駆動アームと、
前記定軌道に設置されて前記第１〜第３昇降体を独自に昇降させる第１〜第３昇降体単独の第１〜第３駆動手段と、
前記第３昇降体に設置されて前記駆動アームを水平方向に回転揺動させる第４駆動手段と、
を具備したことを特徴とするアーム式ロボット。A pair of left and right first lifting bodies and second lifting bodies that independently move up and down substantially vertical parallel orbits;
A third elevating body that elevates and lowers the fixed orbit on which the first elevating body moves up and down separately from the first elevating body;
A rear end portion is connected to the first lifting body so as to be rotatable in the vertical and horizontal directions, a tip portion is connected to the robot working head portion so as to be rotatable in the vertical and horizontal directions, and a substantially vertical plane based on the rear end portion. A first parallel link arm portion having a plurality of parallel arms that move in parallel up and down, and a rear end portion connected to the second elevating body so as to be able to rotate in the vertical and horizontal directions, and a tip portion is vertically connected to the head portion. A link mechanism having a second parallel link arm portion that is coupled to be rotatable in the left-right direction and has a plurality of parallel arms that move in parallel up and down in a substantially vertical plane with the rear end as a base point;
A rear end portion is connected to the third lifting body so as to be rotatable in the vertical and horizontal directions, and a front end portion is connected to the first parallel link arm portion so as to be capable of rotating in the vertical direction so that the first parallel link arm portion moves in parallel links. A drive arm that swings up and down in a substantially vertical plane,
1st to 3rd drive means of the 1st-3rd raising / lowering body independent installed in the above-mentioned fixed orbit and raising and lowering the 1st-3rd raising / lowering body uniquely,
A fourth driving means installed on the third elevating body to rotate and swing the driving arm in a horizontal direction;
An arm type robot characterized by comprising:

前記定軌道を略鉛直な左右一対の支柱の前面に配設し、この左右一対の支柱の間と各支柱の外側面に前記第１駆動手段、第２駆動手段、第３駆動手段を分配して配設したことを特徴とする請求項１記載のアーム式ロボット。The fixed orbit is disposed on the front surface of a pair of left and right pillars that are substantially vertical, and the first driving means, the second driving means, and the third driving means are distributed between the pair of left and right pillars and the outer surface of each pillar. The arm type robot according to claim 1, wherein the arm type robot is arranged.

前記ロボット作業用ヘッド部が、水平方向に所定配列で複数の自動作業機を着脱自在に支持することを特徴とする請求項１又は２記載のアーム式ロボット。3. The arm type robot according to claim 1, wherein the robot working head unit detachably supports a plurality of automatic working machines in a predetermined arrangement in a horizontal direction.