JP3587766B2 - Transfer device - Google Patents

Description

となる。このときのワークＷの水平姿勢角度Θは、

となり、常に一定である。
ここで、第1リンク１０の回転角度θ１を微量分φ回転させると、

となり、

となる。
【００５３】
したがって、微量分φに対してα／（９０°−α）倍の回転角度比でΘの角度が変化する。この変化する割合は、ロボット３の上部アーム６のそのときの揺動角度θによらず、システム設定の角度αによって決まる。
【００５４】
つまり、微量分φによるワーク保持手段１２の姿勢変更は、両端のワーク吸着保持点、または吸着解除点だけでなく、途中位置でも可能で、ワーク保持手段１２を、搬送装置１へ取付けるときに微調整することができる。
【００５５】
図１１、１２は本発明の他の実施形態の搬送装置５５，５６を示す平面図である。搬送装置５５は、前述した搬送装置１のリンク機構のリンクを直列に連結してさらに延長したものである。搬送装置５５では、第２リンク１１の先端に第３リンク５７を設け、この第３リンク５７の先端にさらに第４リンク５８を設けたＭ字状の構造を有する。このように構成することによって、搬送装置１に比べて搬送距離を２倍にすることができる。なお、第３リンク５７および第４リンク５８は、それぞれ歯車とベルトを用いた回転伝達手段によって、ロボット３の上部アーム６に対する第１リンク１１の回転が伝達される。
【００５６】
図１２に示す搬送装置５６では、第２リンク１１の長さを倍にするとともに、第３リンク５７のみ設ける構成とした。このような逆Ｎ字状の構造によって、図１１に示す搬送装置５５に比べて構造を単純にし、かつ搬送装置５５と同じ搬送距離を有するように構成できる。
【００５７】
図１３は、本発明の実施の他の形態の搬送装置４０の構成を示す平面図である。本実施形態の搬送装置４０のリンク機構４１は、前述した搬送装置１のリンク機構９と異なり、ダブルリンク（平行クランク機構）によって構成される。
【００５８】
詳しく説明すると、リンク機構４１は、前述した搬送装置１の第１リンクに対応する第１ダブルリンク４２と、搬送装置１の第２リンクに対応する第２ダブルリンク４３とから構成され、第１ダブルリンク４２は、第１〜第４リンク４４〜４７から構成され、第２ダブルリンク４３は、第１ダブルリンク４２の第４リンク４７を共通に持ち、第４〜第７リンク４７〜５０から構成される。第１ダブルリンク４２は、第１リンク４４と第３リンク４６とが平行であり、第３リンク４５と第４リンク４７とが平行である。第２ダブルリンク４３は、第４リンク４７と第６リンク４９とが平行であり、第５リンク４８と第７リンク５０とが平行である。第２ダブルリンク４３の先端の第６リンク４９に、保持手段１２が固定される。
【００５９】
第１ダブルリンク４２の第１リンク４４が、ロボット３の手首軸によって回転駆動される。第１リンク４４の先端部に取付けられる第７リンク５０は、前述した搬送装置１と同様に、ベルトと歯車から成る回転伝達手段と同様の機構によって、上部アーム６に対する第１リンク４４の回転が伝達される。また、手首に取付けられるもう一方のリンクである第２リンク４５は、歯車などの回転伝達手段によって、上部アーム６に対する第１リンク４４の回転が伝達され、この第２リンク４５は、常に搬送経路Ｌに平行となるように回転する。このような構成によって、第２ダブルリンク４３先端の第６リンク４９も常に搬送経路Ｌに平行となり、この第６リンク４９に固定される保持手段１２の向きも常に一定となり、非反転でワークＷは搬送される。
【００６０】
つぎに、図１４を参照して、搬送装置４０の搬送動作について説明する。ロボット３の上部アーム６を中央位置から図１２において時計回りにα（°）回転させて第２位置に搬送するものとする。ロボット３は、上部アーム６を揺動させるとともに、手首軸で第１リンク４４を回転させる。すると、回転伝達手段によって、上部アーム６に対する第１リンク４４の回転が、第７リンク５０に伝達されて、第７リンク５０が反時計回りに回転するとともに、第２リンク４５も反時計回りに回転する。このように回転し、上部アーム６の揺動角度がα°となったとき、リンク機構４１は一直線状に伸び、ワークＷを第２位置まで搬送することができる。
【００６１】
このとき、手首軸によって駆動される第１リンク４４を、上部アーム６の揺動角度αの（９０°−α）／α倍となるように手首軸を制御し、上部アーム６に対する第１リンク４４の回転を第７リンク５０に伝達するする回転伝達手段は、上部アーム６の揺動角度の１８０°／（９０°−α）倍に拡大するように設定され、上部アーム６に対する第１リンク４４の回転を第４リンク４５に伝達するする回転伝達手段は、上部アーム６の揺動角度と同じ角度だけ第４リンク４５を回転させるように設定される。このように設定されることによって、保持手段１２を搬送経路Lに沿って一直線状に搬送することができる。
【００６２】
図１５は、図１１で示したＭ字状の搬送装置５５にダブルリンクを適用した構造の本発明のさらに他の実施形態の搬送装置７５を示す図であり、図１６は、図１２で示した逆Ｎ字状の搬送装置５６に、ダブルリンクを適用したさらに他の実施形態の搬送装置７６を示す図である。このように、Ｍ字状、逆Ｎ字状のダブルリンク構造の搬送装置であってもよい。
【００６３】
図１７は、本発明の実施の他の形態の搬送装置６０の構成を示す平面図である。搬送装置６０のリンク機構６８は、第１〜第４リンク６１〜６４を有し、第１リンク６１の基端部および第３リンク６３の基端部は、ロボット３の手首に回転可能に取付けられる。このうち、第１リンク６１が、ロボット３の手首軸によって回転駆動される。
【００６４】
第１リンク６１の先端部の下に第２リンク６２の基端部が回転可能に取付けられ、第３リンク３の先端部の下に第４リンク６４の基端部が回転可能に取付けられ、第２リンク２および第４リンク６４の先端部の下に保持手段１２が取付けられる。第２リンク６２および第４リンク６４の先端部の下に連結部材６７を介して保持手段１２が取り付けられる。第２リンク６２の先端部と連結部材６７とは回転可能に連結され、第４リンク６４の先端と連結部材６７とは、第３リンク６３の先端とは異なる位置で連結部材６７に回転可能に連結される。また、第２リンク６２の先端部と第４リンク６４の先端部には、それぞれ歯車６５，６６が固定され、これらの歯車６５，６６は互いに噛合し、この歯車６５，６６を介して連結部材６７が取付けられるので、取り付け部材６７に取付けられる保持手段１２は、水平位置姿勢を一定に保持することができる。
【００６５】
第１〜第４リンク６１〜６４はそれぞれ同じ長さを有し、第１リンク６１と第４リンク６４とが平行に配置され、第２リンク６２と第３リンク６３とが平行に配置され、これらによってひし形のリンク機構６８が構成される。手首軸によって回転駆動される第１リンク６１の上部アーム６に対する回転は、歯車などを用いて第３リンク６３に伝達され、手首軸によって第１リンク６１を回転させることによって、リンク機構６８を折り畳んだり、伸長させたりすることができる。次に、図１８を参照して、リンク機構６８の動きについて説明する。
【００６６】
ロボット３の上部アーム６が中央位置にあるとき、第１リンク６１の下に第２リンク６２が重なり、第３リンク６３の下に第４リンク６４が重なってリンク機構６８が折り畳まれている。上部アーム６を図１８において時計回りに揺動させるとともに、第１リンク６１を手首軸で時計回りに回転させると、第１リンク６１の回転に連動して第２リンク６２および第３リンク６３が反時計周りに回転し、第４リンク６４が時計周りに回転し、やがて第１リンク６１と第２リンク６２と、第３リンク６３と第４リンク６４とが一直線になって伸び、ワークＷが他方側のプレス機２１まで搬送される。
【００６７】
中央位置から第２位置である他方側のプレス機２１まで上部アーム６の揺動角度をα（°）としたとき、手首軸によって駆動される第１リンク６１を、上部アーム６の揺動角度αの（９０°−α）／α倍となるように手首軸が制御され、第３リンク６３が、（９０°＋α）／α倍となるように、上部アーム６に対する第１リンク６１の回転が第３リンク６３に伝達され、これによって、ワークＷを一直線状の搬送経路Lに沿って搬送することができる。
【００６８】
図１９は、上述した搬送装置６０に類似する本発明のさらに他の実施形態の搬送装置１２０を示す平面図である。この搬送装置１２０は、第１〜第６リンク１２１〜１２６からなるリンク機構１２７を有し、前述した搬送装置６０のリンク機構６８を２倍とした構造を有する。
詳しく説明すると、第１リンク１２１と第４リンク１２４は基端部がロボット３の上部アーム６先端に回転可能に取付けられ、第２リンク１２２の基端部は、第１リンク１２１の先端部の下に回転可能に取付けられ、第５リンク１２５は、第４リンク１２４の先端部の下に回転可能に取付けられ、第３リンク１２３は、第２リンク１２２の先端部の下に回転可能に取付けられ、第６リンク１２６は、第５リンク１２５の先端部の下に回転可能に取付けられ、第３リンク１２３の先端部と第６リンク１２６の下に連結部材１２７が回転可能に取付けられ、この連結部材１２７の下に保持手段１２が固定される。
【００６９】
本実施形態の搬送装置１２０も、前述した搬送装置６０と同様に、ロボット３の上部アーム６の揺動に連動して第１リンク１２１を回転駆動し、ロボット３の上部アーム６に対する第１リンク１２１の回転を、第４リンク１２４に伝達し、第１リンク１２１の回転に連動して第４リンク１２４を回転駆動することによって、一直線状の搬送経路Ｌに沿ってワークＷを搬送することができる。
【００７０】
図２０は、本発明のさらに他の実施の形態である搬送装置７０の構成を示す平面図である。搬送装置７０は、図１７で示した搬送装置６０の第１〜第４リンクをダブルリンクにした構造を有する。すなわち、第１ダブルリンク７１はリンク８１〜８４から構成され、第２ダブルリンク７２は第１リンク７１のリンク８４を共通に持つ４つのリンク８４〜８７から構成され、第３ダブルリンク７３は、第１ダブルリンク７１のリンク８１を共通に持つ４つのリンク８１，８９〜９１から構成され、第４ダブルリンク７４は、第３ダブルリンクのリンク９１および第２ダブルリンク７２のリンク８７を共通に持つ４つのリンク８７，９１〜９３から構成され、保持手段１２は、第２リンク７２と第４リンク７４の共通のリンク８７の下に取付けられる。
【００７１】
ロボット３の手首軸によって回転駆動するのは、第１ダブルリンク７１のリンク８２であり、ロボット３の上部アーム６に対するリンク８２の回転は、回転伝達手段によって第２ダブルリンク７２のリンク８５に伝達される。さらに、上部アーム６に対するリンク８２の回転は、歯車などの回転伝達手段によってリンク８１に伝達される。このリンク８１は、搬送中に常に搬送経路Ｌに平行となるように、回転伝達手段のギヤ比は設定される。この場合、ロボットの上部アーム６に対して、（９０°−α）／α倍リンク８２が回転するよう手首軸を駆動し、リンク８５は、リンク８３に対して９０°／（９０°−α）倍回転するように回転伝達手段は設定され、リンク８１は、リンク８３に対してα／（９０°−α）倍回転するように設定する。
【００７２】
また、他の駆動方法として、手首軸でリンク８２を回転駆動し、手首に連結される他の２つのリンク８１，９０を、歯車を用いて回転を伝達するように構成してもよい。この場合、リンク８２は、ロボット３の上部アーム６に対して、（９０°−α）／α倍回転させ、リンク９０は、上部アーム６に対して（９０°−α）／α倍回転させる。
【００７３】
図２１は、図１９で示した搬送装置１２０の各リンクをダブルリンクとした本発明のさらに他の実施形態の搬送装置１３０を示す図である。このような構造であっても、図２０で説明した搬送装置７０と同様に手首軸の駆動を伝達することによって、ワークＷを直線に沿って搬送することができる。
【００７４】
【発明の効果】
以上のように本発明によれば、リンク機構を用いて搬送装置を構成することによって、被搬送物を第１位置から第２位置に一直線状の搬送経路に沿って移動させ、高速で、長距離を搬送し、アームの揺動角度がαのとき、第１リンクと第２リンクとは第１位置から第２位置への保持手段の移動経路上で１８０°の角度をなすことによって、搬送の動作範囲を大きく取ることができる。
【００７５】
また、手首軸で第１リンクを回転させて搬送装置を駆動させることによって、別途にモータを必要とせず、ロボットに備えられる駆動源で駆動することができ、コストダウンが図られる。
【００７６】
また、保持手段用回転伝達手段を用いて、保持手段を回転させながら搬送することによって、非反転で搬送することができる。
【００７７】
また、リンク機構を用いるので、軽量に構成することができ、ロボットに対する負担が少なく、動特性が良好である。
【図面の簡単な説明】
【図１】本発明の搬送装置の動作を説明するための図である。
【図２】本発明の実施の一形態である搬送装置１を用いるロボットシステム２を示す側面図である。
【図３】ロボットシステム２の平面図である。
【図４】搬送装置１による搬送過程を示す図である。
【図５】搬送装置１の内部機構を示す平面図である。
【図６】搬送装置１の内部機構を示す側面図である。
【図７】搬送装置３５の第１遊星歯車２６、第２太陽歯車３６近傍を示す断面図である。
【図８】ロボットのアームの移動速度（ａ）と第２リンクの回転角速度（ｂ）とワークの移動速度（ｃ）との関係を示すグラフである。
【図９】ロボットのアームの移動速度（ａ）と第２リンクの回転角速度（ｂ）とワークの移動速度（ｃ）との関係を示すグラフである。
【図１０】ワークＷの水平位置姿勢角度を説明する図である。
【図１１】本発明の他の実施の形態の搬送装置５５を示す平面図である。
【図１２】本発明のさらに他の実施の形態の搬送装置５６を示す平面図である。
【図１３】本発明のさらに他の実施の形態の搬送装置４０を示す平面図である。
【図１４】搬送装置４０の搬送動作を説明する図である。
【図１５】本発明のさらに他の実施の形態の搬送装置７５を示す平面図である。
【図１６】本発明のさらに他の実施の形態の搬送装置７６を示す平面図である。
【図１７】本発明のさらに他の実施の形態の搬送装置６０を示す平面図である。
【図１８】搬送装置６０の搬送動作を説明する図である。
【図１９】本発明のさらに他の実施の形態の搬送装置１２０を示す平面図である。
【図２０】本発明のさらに他の実施の形態の搬送装置７０を示す平面図である。
【図２１】本発明のさらに他の実施の形態の搬送装置１３０を示す平面図である。
【符号の説明】
１，４０，５５，５６，７５，７６，６０，７０，１２０，１３０， 搬送装置
２ ロボットシステム
３ ロボット
９，６８，１２７ リンク機構
１０，４４，６１，１２１，１３１ 第１リンク
１１，６２，１２２ 第２リンク
１２ 保持手段[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transfer device for transferring a work, and more particularly, to a transfer device attached to a wrist of a robot for use.
[0002]
[Prior art]
For example, when a work is transferred between press machines, a robot is installed between the press machines, and the work is transferred by the robot. At this time, if the interval between the press machines is large, the transfer device is attached to the wrist of the robot, and the work is transferred by the transfer device and the movement of the arm of the robot. An example of the prior art of such a transport device is disclosed in Japanese Utility Model Laid-Open No. 4-42390, “Article transport device”.
[0003]
The transfer device of the related art has a slider and a holding unit that sucks and holds a work and travels along the slider. In order to transfer the work, first, the transfer device is moved to one press machine side by a robot, and the work of one press machine is sucked and held by holding means arranged at one end of the slider. Next, the holding means holding the work is slid to the other end of the slider, and the transfer device is moved to the other press by the robot. Then, when the work reaches the press machine on the other side, the suction holding by the holding means is released.
[0004]
In this way, the workpiece can be transported even when the transport distance is long.
[0005]
[Problems to be solved by the invention]
In the above-described conventional transfer apparatus, the holding means is slid using the screw screw to transfer the sheet, so that there is a problem that the transfer speed is low.
[0006]
In addition, since a driving motor for driving the screw is separately required to drive the transport device, the driving motor must be controlled separately from the robot, which complicates the control.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a transfer device which has a high transfer speed and does not require a separate drive motor.
[0008]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a robot arm having a holding means attached to a wrist of a robot for holding a transferred object detachably, and reciprocatingly swinging between a first position and a second position. Synchronously, in a transport device that reciprocates the holding unit between the first position and the second position to transport the transported object from the first position to the second position,
A link mechanism having a first link attached to the wrist of the robot at the base end, and a second link rotatably connected to the base end at the tip of the first link;
Rotation transmitting means for transmitting the rotation of the first link with respect to the arm to the second link, and rotating the second link with respect to the first link;
The rotation transmitting means is rotatably provided at a base end of the first link, and is rotatably provided at a distal end of the first link, and a sun gear fixedly connected to an arm of the robot. A planetary gear fixed to the base end of the two links, and a timing belt wound around the sun gear and the planetary gear;
By rotating the first link with respect to the arm by the wrist axis of the wrist of the robot while swinging the arm, the rotation is transmitted to the second link by the rotation transmitting means, and the second link is connected to the first link. Rotate against
Assuming that the swing angle of the robot arm from the center position between the first position and the second position is α, the rotation angle of the first link driven by the wrist axis is (90 ° of the swing angle α of the arm). −α) / α times, and the planets relative to the number of teeth of the sun gear so that the rotation angle of the second link is 180 ° / (90 ° −α) times the rotation angle of the first link with respect to the arm. This is a transport device wherein the number of teeth of a gear is set.
[0009]
According to the present invention, the transporting means is constituted by the link mechanism having the first link and the second link, so that the transporting means operates at a much higher speed than the conventional transporting means in which the screw screw is driven to slide and displace. Can be. The robot is, for example, a six-axis articulated robot, and the first link is rotationally driven by its wrist axis. The rotation of the first link with respect to the arm is transmitted to the second link by the rotation transmitting means. Thus, when the first link is rotationally driven by the wrist axis, the second link rotates in conjunction with the rotation. In this manner, the link mechanism of the transport unit can be driven using the wrist shaft of the robot without separately providing a drive motor in the transport unit.
[0013]
The operation of the transport device will be described with reference to FIG. The arm of the robot swings between a first position (left side in FIG. 1) and a second position (right side in FIG. 1), and a link mechanism of the transfer device operates in synchronization with the swing, When the arm is at the first position, the link mechanism extends to the first position, and when at the second position, the link mechanism operates to extend to the second position.
[0014]
In FIG. 1, when the arm of the robot is located at the center position between the first position and the second position, the link is perpendicular to the linear transport path L connecting the first position and the second position. At this time, the first link and the second link are folded so as to overlap with each other and extend along the arm of the robot. The angle of the arm at this time is set to 0 ° in absolute coordinates, and the swing angle when the link is at the second position is set to α °.
[0015]
When the arm is rotated by α ° from 0 ° to the second position, the transferred object held at the tip of the second link moves along the transfer path L connecting the first link and the second link. The first link needs to be rotated (90 ° -α) with respect to the arm while the arm swings from 0 ° to α °. That is, the first link needs to be rotated by (90 ° −α) / α times the swing of the arm.
[0016]
Similarly, while the arm swings from 0 ° to α °, the second link needs to rotate 180 ° with respect to the first link. That is, the second link needs to rotate 180 ° / (90 ° −α) times the rotation angle of the first link with respect to the arm.
[0017]
Therefore, the first link driven by the wrist axis is controlled so as to be (90 ° −α) / α times the swing angle of the arm, and the rotation angle of the second link is controlled by the rotation angle of the first link with respect to the arm. By setting the rotation transmitting means so as to be 180 ° / (90 ° -α) times the angle, the holding means provided at the tip of the second link is moved linearly from the first position to the second position. When the swing angle of the arm is α, the first link and the second link form an angle of 180 ° on the movement path of the holding means from the first position to the second position, thereby making the conveyance A large operating range can be obtained.
[0018]
According to a second aspect of the present invention, the link mechanism is a link mechanism in which three or more links are connected in series, a link mechanism having a double link, or a link mechanism having a rhombus link. And
[0019]
According to the present invention, the link mechanism of the transport device may be M-shaped as shown in FIG. 11 or inverted N-shaped as shown in FIG. 12, and the first link and the inverted link as shown in FIG. Each of the second links may constitute a double link (parallel crank mechanism), or as shown in FIG. 17, the first link and the second link may constitute a diamond-shaped link mechanism. Alternatively, a link mechanism combining these may be used.
[0021]
According to a third aspect of the present invention, the holding means is rotatably provided at a tip end of the second link, and transmits the rotation of the second link with respect to the first link so that the rotation angle of the holding means is equal to the first angle. The rotation transmission means for the holding means is set so as to be half the rotation angle of the second link with respect to the link, and the direction of the conveyed object being conveyed is made constant.
[0022]
The operation of the holding means will be described with reference to FIG. The rotation of the second link with respect to the first link is transmitted to the holding unit by the rotation transmitting unit for the holding unit, and the holding unit also rotates in synchronization with the swing of the arm. In order for the object held by the holding means not to change its direction during the transfer, the robot arm rotates from 0 ° to α ° and the second link rotates by 180 ° with respect to the first link. , It is necessary to rotate the holding means by 90 ° with respect to the second link. That is, the holding means rotates by half the rotation angle of the second link with respect to the first link.
[0023]
Therefore, by setting the rotation transmission means for the holding means such that the rotation angle of the second link with respect to the first link is enlarged by a factor of two and transmitted to the holding means, the direction of the transferred object is not changed, It can be transported non-inverted.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 2 is a side view showing a robot system 2 including a transfer device 1 according to an embodiment of the present invention, and FIG. 3 is a plan view thereof. The transfer device 1 is attached to the wrist 7 of the robot 3 and is used to transfer the work W between the pair of presses 20 and 21.
[0026]
The robot 3 is a 6-axis vertical articulated robot, and has a base 4 fixed to the floor, a lower arm 5, an upper arm 66, and a wrist 7. The lower arm 5 is attached to the base 4 so that the lower end can pivot around a vertical first axis J1 and can rotate back and forth about a horizontal second axis J2. The base end of the upper arm 6 is attached to the upper end of the lower arm 5 so as to be rotatable up and down around a horizontal third axis J3. The wrist 7 attached to the tip of the upper arm 6 is rotatably mounted around a fourth axis J4 parallel to the axis of the upper arm 6 and rotatable around a fifth axis J5 perpendicular to the axis of the upper arm 6. Attached to Then, the transport device 1 is attached to the wrist 7. The wrist axis of the wrist 7 rotates around a sixth axis J6 perpendicular to the fifth axis J5.
[0027]
Each joint axis J1 to J6 of the robot 3 is individually driven to rotate by a servomotor, and the wrist axis drives the first link 10 to rotate about the sixth axis J6 with respect to the upper arm 6.
[0028]
The transport device 1 includes a link mechanism 9 including a first link 10 and a second link 11, and a holding unit 12 provided at a distal end of the second link 11. The second link 11 has the same length as the first link 10, and the base end 11a is attached to the distal end 10b of the first link 10 so as to be rotatable around the rotation axis A1 parallel to the sixth axis J6. Then, the holding means 12 is attached to the distal end portion 11b of the second link 11. The holding unit 12 has a plurality of suction cups 13, and the work W is detachably held by these suction cups 13.
[0029]
The robot 3 of the robot system 2 is installed at the center of the two presses 20 and 21, and is moved from one press 20 at the first position on the left in FIG. 3 to the other at the second position on the right in FIG. The work W is transported to the press 21. The robot 3 holds the transfer device 1 substantially horizontally so that the sixth axis J6 is vertical, swings the upper arm 6 about the first axis J1, and synchronizes with the swing of the upper arm 6. The link mechanism 9 of the transport device 1 is reciprocated.
[0030]
Next, the transport operation of the robot system 2 will be described in more detail with reference to FIG.
[0031]
As shown in FIG. 4A, the transfer device 1 is extended to one of the presses 20 together with the upper arm 6, and after the work W is held by the holding means 12, the first link 10 is moved in the first rotation direction (FIG. 4), the second link 11 rotates in the second rotation direction (counterclockwise in FIG. 4), and the holding means 12 moves in the first rotation direction (clockwise in FIG. 4). Rotate. By rotating in this manner, the workpiece W starts to move while maintaining the same orientation as the held state.
[0032]
When the first link 10 is further rotated in the first rotation direction, the transport device 1 is moved through the state shown in FIG. 4 (2) at the center between the press machines 20 and 21 as shown in FIG. 4 (3). Will be folded. At this time, the upper arm 6 of the robot 3 is arranged perpendicular to the transport path L, and the first link 10 and the second link 11 are folded and arranged perpendicular to the transport path L.
[0033]
Further, by swinging the upper arm 6 to the other side and rotating the first link 10 in the first rotation direction, the transfer device 1 extends to the other side while maintaining the work W in the same direction. . In this way, through the state of FIG. 4D, the first link 10 and the second link 11 are extended until they are aligned, and the work W is transported to the press 21 on the other side. As shown in FIG. 4 (5), the direction of the work W after the completion of the transfer is the same as the direction of the work W at the start of the transfer shown in (1).
[0034]
Next, the link mechanism 9 will be described. The link mechanism 9 transmits the rotation of the first link 10, the second link 11, and the rotation of the first link 10 with respect to the upper arm 6 of the robot to the second link 11, and transmits the second link 11 to the first link 10. The rotation transmitting means 8 includes a rotation transmitting means 8 for rotating the rotation of the second link 11 with respect to the first link 10 to the holding means 12, and a rotation transmitting means 15 for the holding means for rotating the holding means 12. FIG. 5 is a plan view showing the internal structure of the transport device 1, and FIG. 6 is a side view thereof.
[0035]
The first link 10 has a hollow first link main body 22, a base end 10 a of which is fixed to the wrist 7, and the first link main body 22 is rotationally driven by a servomotor M <b> 6 that drives a wrist axis of the robot. . A first sun gear 25 is provided inside the first link body 22 on the base end 10a side. The first sun gear 25 is fixedly connected to the upper arm 6 of the robot, and when the first link 10 is rotated around the wrist axis, the first sun gear 25 relatively moves to the first link. 10 will rotate. A first planetary gear 26 rotatably supported around a rotation axis A1 parallel to the axis J6 of the sixth shaft is provided at the distal end portion 10b of the first link body 22. A timing belt 27 is wound around the planetary gears 26. The first sun gear 25, the first planetary gear 26, and the timing belt 27 constitute the rotation transmitting unit 8. The first planetary gear 26 is rotatably supported on the first link main body 22 by a bearing 28, the base end 11 a of the second link 11 is fixed, and the second planetary gear 26 is integrally formed with the first planetary gear 26. The link 11 rotates.
[0036]
A second sun gear 36 is provided at the base end of the hollow second link body 39, and a second planetary gear 37 is provided at the distal end. The holding means 12 is connected to the second planetary gear 37, The holding means 12 rotates together with the planetary gear 37. The timing belt 38 is wound around the second sun gear 36 and the second planetary gear 37. The second sun gear 36, the second planetary gear 37, and the timing belt 38 constitute the rotation transmission unit 15 for the holding unit.
[0037]
As shown in FIG. 7, the second sun gear 36 is fixedly connected to the first link body 22 and rotates integrally with the first link 10. The first planetary gear 26 and the second sun gear 36 have a common rotation axis A1, but as shown in FIG. 7, the first planetary gear 26 is fixedly connected to a second link body 39 via a shaft 34. Then, the second sun gear 36 is fixedly connected to the first link main body 22 and is integrated with the first link 10 by rotating around the rotation axis A1 integrally with the second link 11. The second planetary gear 37 is rotatably supported by the second link main body 39 at the tip end 11a of the second link 11 main body so as to be rotatable around a rotation axis A2 parallel to the rotation axis A1.
[0038]
Since the timing belt 27 is wound around from the first sun gear 25 to the first planetary gear 26, as shown in FIG. 5, with the gear 25 fixed, the first link 10 is moved in the first rotational direction (FIG. 5). 5, the timing belt 26 rotates as shown by the arrow in FIG. 5, whereby the first planetary gear 26 rotates in the second rotation direction (counterclockwise). As described above, the first planetary gear 26 and the second link 11 are fixed and rotate integrally, so that the first planetary gear 26 is driven to rotate in the first rotational direction to rotate the first planetary gear 26 in the first rotational direction. The second link 11 can be rotated together with the gear 26 in the second rotation direction.
[0039]
As described with reference to FIG. 1, when the swing angle of the upper arm 6 is α (°) from the center to the press 21 on the other side, which is the second position, the first link 10 driven by the wrist shaft is The wrist axis is controlled so that the swing angle α of the upper arm 6 becomes (90 ° −α) / α times, and the rotation angle of the second link 11 becomes 180 ° of the rotation angle of the first link with respect to the upper arm 6. By setting the rotation transmitting means 8 to be / (90 ° -α) times, the holding means 12 provided at the tip of the second link 11 is linearly moved from one press machine 20 to the other press machine 21. Can be moved to
[0040]
To control the wrist axis so that the first link 10 becomes (90 ° −α) / α times the swing angle α of the upper arm 6 is, for example, a swing angle α of the arm 6. Is 30 °, the rotation angle of the first link 10 is controlled to be twice as large as that of the arm 6, and when the swing angle α is 45 °, the rotation angle of the first link 10 is When the swing angle is 60 °, the rotation angle of the first link 10 is controlled to be の of the swing angle of the arm 6.
[0041]
Setting the rotation transmitting means 8 so that the rotation angle of the second link 11 is 180 ° / (90 ° −α) times the rotation angle of the first link with respect to the upper arm 6 is mentioned as a specific example. For example, when the swing angle α of the arm 6 is 30 °, the rotation transmitting means 8 is set so that the rotation angle of the second link 11 with respect to the first link 10 is tripled, and the swing angle α is 45 °. At this time, the rotation angle of the second link 11 is set to be four times, and when the swing angle α is 60 °, the rotation angle of the second link 11 is set to be six times.
[0042]
That is, the number of teeth of the first sun gear 25 is selected to be 180 ° / (90 ° −α) times the number of teeth of the first planetary gear 26 of the rotation transmitting means 8.
[0043]
Similarly, as described with reference to FIG. 1, the rotation transmitting unit 15 for the holding unit is set such that the rotation angle of the second link 11 with respect to the first link 10 is enlarged to 倍 times and transmitted to the holding unit 12. By doing so, it is possible to convey the non-inverted object without changing the direction of the object.
[0044]
That is, the number of teeth of the second sun gear 36 is selected to be １ ／ of the number of teeth of the second planetary gear 37 of the rotation transmitting means 15 for the holding means.
[0045]
Note that FIG. 1 shows only the state when moving from the center to the second position, but the movement from the first position to the center appears symmetrically.
[0046]
FIG. 8 is a graph showing a relationship between the moving speed (a) of the tip of the wrist of the upper arm 6, the rotational speed (b) of the link, and the moving speed (c) of the work W.
[0047]
When the arm 6 swings from the first position to the second position, the first link 10 rotates 180 °. The robot 3 is controlled such that the tip of the wrist of the upper arm 6 moves at a constant speed along the transport path L. Therefore, as shown in FIG. 8A, when the tip of the wrist moves at a constant speed, the rotational speed of the link becomes the highest at the center as shown in FIG. 8B.
[0048]
Therefore, as shown in FIG. 8C, the moving speed of the work W moves at a much higher speed in the central portion than the moving speed of the arm 6.
[0049]
In the link mechanism 9, the first link 10 and the second link 11 are open near the first position and the second position, and the rigidity is low, but the first link 10 and the second link 11 are overlapped at the center. Folded and rigid. Therefore, by moving the upper arm 6 at a constant speed, it is possible to reduce the moving speed near the first and second positions with low rigidity, and to increase the moving speed in the central portion with high rigidity to stably convey. it can.
[0050]
Conversely, as shown in FIG. 9A, the swing speed of the upper arm 6 is controlled so that the moving speed of the tip of the upper arm 6 becomes slower at the center between the first position and the second position. However, the link speed may be controlled to be constant.
[0051]
Next, the horizontal posture angle of the held work W will be described with reference to FIG.
[0052]
The swing angle when the upper arm 6 of the robot 3 swings from the center to the second position is α, the swing angle at an arbitrary position of the arm 6 is θ, and the rotation angle of the first link 10 is θ1. If the rotation angle of the second link 11 is θ2 and the rotation angle of the holding means 12 is θ3,

It becomes. At this time, the horizontal posture angle の of the workpiece W is

And is always constant.
Here, when the rotation angle θ1 of the first link 10 is rotated by a minute amount φ,

Becomes

It becomes.
[0053]
Therefore, the angle of Θ changes at a rotation angle ratio of α / (90 ° −α) times the minute amount φ. This rate of change is determined by the angle α set by the system, not by the swing angle θ of the upper arm 6 of the robot 3 at that time.
[0054]
That is, the posture of the work holding means 12 can be changed by the minute amount φ not only at the work suction holding points or the suction release points at both ends, but also at an intermediate position. Can be adjusted.
[0055]
FIGS. 11 and 12 are plan views showing transfer devices 55 and 56 according to another embodiment of the present invention. The transfer device 55 is obtained by further connecting the links of the link mechanism of the transfer device 1 described above in series. The transport device 55 has an M-shaped structure in which a third link 57 is provided at the tip of the second link 11 and a fourth link 58 is further provided at the tip of the third link 57. With this configuration, the transport distance can be doubled as compared with the transport device 1. The rotation of the first link 11 with respect to the upper arm 6 of the robot 3 is transmitted to the third link 57 and the fourth link 58 by rotation transmission means using a gear and a belt, respectively.
[0056]
12, the length of the second link 11 is doubled, and only the third link 57 is provided. With such an inverted N-shaped structure, the structure can be simplified as compared with the transfer device 55 shown in FIG. 11, and can be configured to have the same transfer distance as the transfer device 55.
[0057]
FIG. 13 is a plan view showing a configuration of a transport device 40 according to another embodiment of the present invention. The link mechanism 41 of the transport device 40 of the present embodiment is configured by a double link (parallel crank mechanism), unlike the link mechanism 9 of the transport device 1 described above.
[0058]
More specifically, the link mechanism 41 includes a first double link 42 corresponding to the first link of the transport device 1 and a second double link 43 corresponding to the second link of the transport device 1. The double link 42 includes first to fourth links 44 to 47, and the second double link 43 has the fourth link 47 of the first double link 42 in common, and the fourth to seventh links 47 to 50. Be composed. In the first double link 42, the first link 44 and the third link 46 are parallel, and the third link 45 and the fourth link 47 are parallel. In the second double link 43, the fourth link 47 and the sixth link 49 are parallel, and the fifth link 48 and the seventh link 50 are parallel. The holding means 12 is fixed to the sixth link 49 at the tip of the second double link 43.
[0059]
The first link 44 of the first double link 42 is driven to rotate by the wrist axis of the robot 3. The seventh link 50 attached to the distal end of the first link 44 can rotate the first link 44 with respect to the upper arm 6 by a mechanism similar to a rotation transmitting unit including a belt and a gear, similarly to the above-described transport device 1. Is transmitted. A second link 45, which is the other link attached to the wrist, receives the rotation of the first link 44 with respect to the upper arm 6 by a rotation transmission means such as a gear. Rotate so as to be parallel to L. With such a configuration, the sixth link 49 at the tip of the second double link 43 is also always parallel to the transport path L, and the direction of the holding means 12 fixed to the sixth link 49 is always constant. Is transported.
[0060]
Next, the transport operation of the transport device 40 will be described with reference to FIG. The upper arm 6 of the robot 3 is rotated clockwise by α (°) in FIG. 12 from the center position and is conveyed to the second position. The robot 3 swings the upper arm 6 and rotates the first link 44 with the wrist axis. Then, the rotation of the first link 44 with respect to the upper arm 6 is transmitted to the seventh link 50 by the rotation transmitting means, so that the seventh link 50 rotates counterclockwise and the second link 45 also rotates counterclockwise. Rotate. When the rotation is performed in this manner and the swing angle of the upper arm 6 becomes α °, the link mechanism 41 extends in a straight line, and can convey the work W to the second position.
[0061]
At this time, the wrist axis is controlled such that the first link 44 driven by the wrist axis is (90 ° −α) / α times the swing angle α of the upper arm 6, and the first link to the upper arm 6 is controlled. The rotation transmitting means for transmitting the rotation of the rotation of the upper arm 44 to the seventh link 50 is set so as to expand by 180 ° / (90 ° −α) times the swing angle of the upper arm 6, and the first link to the upper arm 6 is provided. The rotation transmitting means for transmitting the rotation of the 44 to the fourth link 45 is set to rotate the fourth link 45 by the same angle as the swing angle of the upper arm 6. With this setting, the holding unit 12 can be transported in a straight line along the transport path L.
[0062]
FIG. 15 is a view showing a transfer device 75 according to still another embodiment of the present invention having a structure in which a double link is applied to the M-shaped transfer device 55 shown in FIG. 11, and FIG. It is a figure which shows the conveyance apparatus 76 of further another embodiment which applied the double link to the conveyance apparatus 56 of the reverse N shape. As described above, a transfer device having an M-shaped or inverted N-shaped double link structure may be used.
[0063]
FIG. 17 is a plan view showing a configuration of a transport device 60 according to another embodiment of the present invention. The link mechanism 68 of the transfer device 60 has first to fourth links 61 to 64, and the base end of the first link 61 and the base end of the third link 63 are rotatably attached to the wrist of the robot 3. Can be The first link 61 is rotationally driven by the wrist axis of the robot 3.
[0064]
The base end of the second link 62 is rotatably mounted below the distal end of the first link 61, and the base end of the fourth link 64 is rotatably mounted below the distal end of the third link 3, The holding means 12 is attached below the distal ends of the second link 4 and the fourth link 64. The holding means 12 is attached below the distal ends of the second link 62 and the fourth link 64 via a connecting member 67. The distal end of the second link 62 and the connecting member 67 are rotatably connected, and the distal end of the fourth link 64 and the connecting member 67 are rotatably connected to the connecting member 67 at a position different from the distal end of the third link 63. Be linked. Gears 65 and 66 are fixed to the distal end of the second link 62 and the distal end of the fourth link 64, respectively. The gears 65 and 66 mesh with each other, and are connected to each other through the gears 65 and 66. Since the 67 is attached, the holding means 12 attached to the attachment member 67 can keep the horizontal position and posture constant.
[0065]
The first to fourth links 61 to 64 have the same length, the first link 61 and the fourth link 64 are arranged in parallel, the second link 62 and the third link 63 are arranged in parallel, These form a diamond-shaped link mechanism 68. The rotation of the first link 61, which is rotationally driven by the wrist axis, with respect to the upper arm 6 is transmitted to the third link 63 using a gear or the like, and the link mechanism 68 is folded by rotating the first link 61 with the wrist axis. And can be extended. Next, the movement of the link mechanism 68 will be described with reference to FIG.
[0066]
When the upper arm 6 of the robot 3 is at the center position, the second link 62 overlaps below the first link 61, the fourth link 64 overlaps below the third link 63, and the link mechanism 68 is folded. When the upper arm 6 is swung clockwise in FIG. 18 and the first link 61 is rotated clockwise about the wrist axis, the second link 62 and the third link 63 are interlocked with the rotation of the first link 61. The counterclockwise rotation causes the fourth link 64 to rotate clockwise, and the first link 61 and the second link 62 and the third link 63 and the fourth link 64 eventually extend in a straight line, and the work W It is transported to the other press machine 21.
[0067]
Assuming that the swing angle of the upper arm 6 is α (°) from the center position to the other side of the press machine 21 at the second position, the first link 61 driven by the wrist shaft is connected to the swing angle of the upper arm 6. The rotation of the first link 61 with respect to the upper arm 6 is controlled such that the wrist axis is controlled to be (90 ° −α) / α times α, and the third link 63 is (90 ° + α) / α times. Is transmitted to the third link 63, whereby the workpiece W can be transported along the straight transport path L.
[0068]
FIG. 19 is a plan view showing a transport device 120 according to still another embodiment of the present invention, which is similar to the transport device 60 described above. The transport device 120 has a link mechanism 127 including first to sixth links 121 to 126, and has a structure in which the link mechanism 68 of the transport device 60 described above is doubled.
More specifically, the first link 121 and the fourth link 124 have their base ends rotatably attached to the distal end of the upper arm 6 of the robot 3, and the base end of the second link 122 is located at the distal end of the first link 121. The fifth link 125 is rotatably mounted below the distal end of the fourth link 124, and the third link 123 is rotatably mounted below the distal end of the second link 122. The sixth link 126 is rotatably mounted below the distal end of the fifth link 125, and the connecting member 127 is rotatably mounted below the distal end of the third link 123 and the sixth link 126. The holding means 12 is fixed below the connecting member 127.
[0069]
Similarly to the above-described transfer device 60, the transfer device 120 of the present embodiment also drives the first link 121 to rotate in conjunction with the swing of the upper arm 6 of the robot 3, and the first link 121 to the upper arm 6 of the robot 3 By transmitting the rotation of 121 to the fourth link 124 and rotating the fourth link 124 in conjunction with the rotation of the first link 121, the workpiece W can be transported along the straight transport path L. it can.
[0070]
FIG. 20 is a plan view showing a configuration of a transport device 70 according to still another embodiment of the present invention. The transport device 70 has a structure in which the first to fourth links of the transport device 60 shown in FIG. 17 are double links. That is, the first double link 71 is composed of links 81 to 84, the second double link 72 is composed of four links 84 to 87 that share the link 84 of the first link 71, and the third double link 73 is The fourth double link 74 includes a link 91 of the third double link 72 and a link 87 of the second double link 72. The holding means 12 is attached below the common link 87 of the second link 72 and the fourth link 74.
[0071]
It is the link 82 of the first double link 71 that is rotationally driven by the wrist axis of the robot 3, and the rotation of the link 82 with respect to the upper arm 6 of the robot 3 is transmitted to the link 85 of the second double link 72 by the rotation transmitting means. Is done. Further, the rotation of the link 82 with respect to the upper arm 6 is transmitted to the link 81 by rotation transmission means such as a gear. The gear ratio of the rotation transmitting means is set such that the link 81 is always parallel to the transport path L during the transport. In this case, the wrist axis is driven so that the (90 ° −α) / α-fold link 82 rotates with respect to the upper arm 6 of the robot, and the link 85 moves 90 ° / (90 ° −α) with respect to the link 83. The rotation transmitting means is set to rotate twice, and the link 81 is set to rotate by α / (90 ° −α) times relative to the link 83.
[0072]
Further, as another driving method, the link 82 may be rotationally driven by the wrist shaft, and the other two links 81 and 90 connected to the wrist may be configured to transmit the rotation using gears. In this case, the link 82 is rotated by (90 ° −α) / α times with respect to the upper arm 6 of the robot 3, and the link 90 is rotated by (90 ° −α) / α times with respect to the upper arm 6. .
[0073]
FIG. 21 is a diagram showing a transport device 130 according to still another embodiment of the present invention in which each link of the transport device 120 shown in FIG. 19 is a double link. Even with such a structure, the work W can be conveyed along a straight line by transmitting the drive of the wrist shaft similarly to the conveyance device 70 described with reference to FIG.
[0074]
【The invention's effect】
As described above, according to the present invention, by configuring a transport device using a link mechanism, an object to be transported can be moved from a first position to a second position along a straight transport path, and can be moved at high speed and long. The first link and the second link form an angle of 180 ° on the movement path of the holding means from the first position to the second position when the arm is swung and the swing angle of the arm is α. Can have a large operating range.
[0075]
In addition, by driving the transport device by rotating the first link with the wrist axis, it is possible to drive the transport device with a drive source provided in the robot without requiring a separate motor, thereby reducing costs.
[0076]
In addition, by using the rotation transmitting means for the holding means and conveying while rotating the holding means, it is possible to carry the paper in a non-inverted manner.
[0077]
Further, since the link mechanism is used, the structure can be made lightweight, the load on the robot is small, and the dynamic characteristics are good.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the operation of a transport device of the present invention.
FIG. 2 is a side view showing a robot system 2 using the transfer device 1 according to one embodiment of the present invention.
FIG. 3 is a plan view of the robot system 2.
FIG. 4 is a view showing a transfer process by the transfer device 1.
FIG. 5 is a plan view showing an internal mechanism of the transport device 1.
FIG. 6 is a side view showing an internal mechanism of the transport device 1.
FIG. 7 is a sectional view showing the vicinity of a first planetary gear 26 and a second sun gear 36 of the transfer device 35.
FIG. 8 is a graph showing a relationship between a moving speed (a) of a robot arm, a rotational angular speed (b) of a second link, and a moving speed (c) of a work.
FIG. 9 is a graph showing a relationship among a moving speed (a) of a robot arm, a rotational angular speed (b) of a second link, and a moving speed (c) of a work.
FIG. 10 is a diagram illustrating a horizontal position / posture angle of a work W.
FIG. 11 is a plan view showing a transfer device 55 according to another embodiment of the present invention.
FIG. 12 is a plan view showing a transfer device 56 according to still another embodiment of the present invention.
FIG. 13 is a plan view showing a transfer device 40 according to still another embodiment of the present invention.
FIG. 14 is a diagram illustrating a transport operation of the transport device 40.
FIG. 15 is a plan view showing a transfer device 75 according to still another embodiment of the present invention.
FIG. 16 is a plan view showing a transfer device 76 according to still another embodiment of the present invention.
FIG. 17 is a plan view showing a transfer device 60 according to still another embodiment of the present invention.
FIG. 18 is a diagram illustrating a transport operation of the transport device 60.
FIG. 19 is a plan view showing a transfer device 120 according to still another embodiment of the present invention.
FIG. 20 is a plan view showing a transfer device 70 according to still another embodiment of the present invention.
FIG. 21 is a plan view showing a transfer device 130 according to still another embodiment of the present invention.
[Explanation of symbols]
1, 40, 55, 56, 75, 76, 60, 70, 120, 130, transfer device 2, robot system 3, robot 9, 68, 127 link mechanism 10, 44, 61, 121, 131 first link 11, 62, 122 second link 12 holding means

Claims (3)

A holding means attached to a wrist of the robot for holding the object in a detachable manner, and holding the holding means in synchronization with an arm of the robot reciprocating between a first position and a second position; The holding means is reciprocated between the first position and the second position in synchronism with the arm of the robot that reciprocates between the first position and the second position to move the object from the first position to the second position. In the transfer device to transfer to
A link mechanism having a first link attached to the wrist of the robot at the base end, and a second link rotatably connected to the base end at the tip of the first link;
Rotation transmitting means for transmitting the rotation of the first link with respect to the arm to the second link, and rotating the second link with respect to the first link;
The rotation transmitting means is rotatably provided at a base end of the first link, and is rotatably provided at a distal end of the first link, and a sun gear fixedly connected to an arm of the robot. A planetary gear fixed to the base end of the two links, and a timing belt wound around the sun gear and the planetary gear;
By rotating the first link with respect to the arm by the wrist axis of the wrist of the robot while swinging the arm, the rotation is transmitted to the second link by the rotation transmitting means, and the second link is connected to the first link. Rotate against
Assuming that the swing angle of the robot arm from the center position between the first position and the second position is α, the rotation angle of the first link driven by the wrist axis is (90 ° of the swing angle α of the arm). -Α) / α times, and the planets with respect to the number of teeth of the sun gear so that the rotation angle of the second link is 180 ° / (90 ° −α) times the rotation angle of the first link with respect to the arm. A transfer device wherein the number of gear teeth is set. 2. The transport apparatus according to claim 1, wherein the link mechanism is a link mechanism in which three or more links are connected in series, a link mechanism having a double link, or a link mechanism having a rhombus link. . The holding means is rotatably provided at the distal end of the second link, and transmits the rotation of the second link with respect to the first link so that the rotation angle of the holding means is equal to the rotation angle of the second link with respect to the first link. 3. The transfer device according to claim 1, wherein the rotation transmission means for the holding means is set so as to be 1/2, and the direction of the conveyed object during conveyance is constant.

Images