JP3897205B2

JP3897205B2 - Reduction gear

Info

Publication number: JP3897205B2
Application number: JP04652698A
Authority: JP
Inventors: 利秀辻; 賢昭外村; 傑下川
Original assignee: Hochiki Corp
Current assignee: Hochiki Corp
Priority date: 1998-02-27
Filing date: 1998-02-27
Publication date: 2007-03-22
Anticipated expiration: 2018-02-27
Also published as: JPH11247950A

Description

【０００１】
【発明の属する技術分野】
本発明は、ダブル遊星歯車装置を利用して大きな減速比を得るようにした減速装置に関する。
【０００２】
【従来の技術】
従来、１／１００を超える大きな減速比を得るための減速装置としては、例えば図５のようなハーモニックドライブ装置が知られている。
図５（Ａ）において、ハーモニックドライブ装置は、ウェーブ・ジェネレータ１０１、フレクスプライン１０２及びサーキュラ・スプライン１０３で構成される。ウェーブ・ジェネレータ１０１は、楕円形カムの外周に、薄肉のボールベアリングが嵌められ、全体が楕円形をしている。フレクスプライン１０２は薄型のカップ状をした金属弾性体であり、カップの開口部外周にギアが刻まれている。
【０００３】
更にサーキュラ・スプライン１０３は剛体リングであり、内周にフレクスプライン１０２と同じ大きさのギアが刻まれており、フレクスプライン１０２より歯数が２枚多くなっている。フレクスプライン１０２は、ウェーブ・ジェネレータ１０１によって楕円状態に撓められ、楕円の長軸の部分でサーキャラ・スプライン１０３とギアが噛み合い、短軸部分でギアが完全に離れた状態となる。
【０００４】
図５（Ａ）においてサーキュラ・スプライン１０３を固定し、図５（Ｂ）のように、ウェーブ・ジェネレータ１０１に入力回転を伝達して時計方向へ回すと、フレクスプライン１０２は弾性変形し、サーキュラ・スプライン１０３とのギアの噛合い位置が順次移動する。
図５（Ｃ）のように、ウェーブ・シェネレータ１０１が１回転すると、フレクススプランイ１０２はサーキュラ・スプラン１０３より歯数が２枚少ないため、ウェーブ・ジェネレータ１０１の回転方向とは逆の反時計方向に歯数差２枚でだけ移動し、このフレクスプライン１０２の動きが出力として取り出される。
【０００５】
【発明が解決しようとする課題】
しかしながら、このような従来のハーモニックドライブ装置にあっては、特殊な形状の部品を必要とするために高価であり、また原理的に減速比が１／２００程度が限界であるという問題があった。
本発明は、このような従来の問題点に鑑みてなされたもので、ダブル遊星歯車の利用によって数百分の１から数千分の１といった高減速比が容易に得られるコスト的に安価な減速装置を提供することを目的とする。
【０００６】
【発明が解決しようとする課題】
この目的を達成するため本発明の減速装置は次のように構成する。まず本発明の減速装置は、第１太陽歯車、第１内歯歯車、第１太陽歯車と第１内歯歯車の間でそれぞれに噛み合わされた複数の第１遊星歯車、及び複数の第１遊星歯車の自転軸を互いに連結して複数の第１遊星歯車の公転を取り出す第１キャリアを備えた第１遊星歯車装置と、第２太陽歯車、第２内歯歯車、第２太陽歯車と第２内歯歯車の間でそれぞれに噛み合わされた複数の第２遊星歯車、及び複数の第２遊星歯車の自転軸を互いに連結して複数の第２遊星歯車の公転を取り出す第２キャリアを備え、第１太陽歯車と第１内歯歯車の歯数比とは異なる第２太陽歯車と第２内歯歯車の歯数比を有し、第１遊星歯車装置と同じ中心軸線上に配置された第２遊星歯車装置とで構成される。
【０００７】
このような第１遊星歯車装置と第２遊星歯車装置を備えたダブル遊星歯車につき、本願の第１発明にあっては、第１キャリアと第２キャリアは第１遊星歯車装置と第２遊星歯車装置の間で互いに公転軸を合わせて連結し、更に第１キャリアは第２遊星歯車装置側とは反対側に入力軸を取り出し、第１内歯歯車と第２内歯歯車を連結してフリーとし、第１太陽歯車を固定し、更に第２太陽歯車から出力軸を取り出したことを特徴とする。
【０００８】
この第１発明につき、第１太陽歯車の歯数をＺ11、第１遊星歯車の歯数をＺ12、第１内歯歯車の歯数をＺ13、第２太陽歯車の歯数をＺ21、第２遊星歯車の歯数をＺ22、第２内歯歯車の歯数をＺ23とするとき、入力軸の入力回転Ａと出力軸の出力回転Ｃとの減速比（Ｃ／Ａ）は、
【０００９】
【数４】

【００１０】
で与えられる。この場合、右辺分母が歯数の乗算により大きな値をとり、右辺分子は歯数乗算結果の差となるため、より小さな値をとり、入力回転Ａに対する出力回転Ｃの減速比（Ｃ／Ａ）は、数百分の１から数千分の１の減速比を実現できる。本願の第２発明は、第１発明と同じ第１遊星歯車装置と第２遊星歯車装置を備えたダブル遊星歯車につき、第１内歯歯車と第２内歯歯車を連結して入力軸を取り出し、第１キャリアと第２キャリアは第１遊星歯車装置と第２遊星歯車装置の間で互いに公転軸を合わせて連結してフリーとし、第１太陽歯車を固定し、更に第２太陽歯車から出力軸を取り出したことを特徴とする。
【００１１】
この場合の入力軸の入力回転Ｂと出力軸の出力回転Ｃとの減速比（Ｃ／Ｂ）は、
【００１２】
【数５】

【００１３】
で与えられる。
この場合、右辺分母が歯数の乗算により大きな値をとり、右辺分子は歯数乗算結果の差となるため、より小さな値をとり、入力回転Ａに対する出力回転Ｃの減速比（Ｃ／Ａ）は、数百分の１から数千分の１の減速比を実現できる。
本願の第３発明は、第１発明と同じ第１遊星歯車装置と第２遊星歯車装置を備えたダブル遊星歯車装置につき、第１内歯歯車と第２内歯歯車を連結して入力軸を取り出し、第１太陽歯車と第２太陽歯車を連結してフリーとし、第１キャリアを固定し、更に第２遊星歯車の第２キャリアから出力軸を取り出したことを特徴とする。
【００１４】
この場合の入力軸の入力回転Ｂと出力軸の出力回転Ｃとの減速比（Ｃ／Ｂ）は、
【００１５】
【数６】

【００１６】
で与えられる。この場合も、右辺分母が歯数の乗算により大きな値をとり、右辺分子は歯数乗算結果の差となるため、より小さな値をとり、入力回転Ｂに対する出力回転Ｃの減速比（Ｃ／Ｂ）は、数百分の１から数千分の１の減速比を実現できる。本願の第３発明は、第１発明と同じ第１遊星歯車装置と第２遊星歯車装置を備えたダブル遊星歯車につき、第１キャリアと第２キャリアは第１遊星歯車装置と第２遊星歯車装置の間で互いに公転軸を合わせて連結し、更に第１キャリアは第２遊星歯車装置側とは反対側に入力軸を取り出し、第１太陽歯車と前記第２太陽歯車を連結してフリーとし、第１内歯歯車を固定し、更に第２内歯歯車から出力軸を取り出したことを特徴とする。
【００１７】
この場合の入力軸の入力回転Ａと出力軸の出力回転Ｃとの減速比（Ｃ／Ａ）は、
【００１８】
【数７】

【００１９】
で与えられる。
この場合も、右辺分母が歯数の乗算により大きな値をとり、右辺分子は歯数乗算結果の差となるため、より小さな値をとり、入力回転Ａに対する出力回転Ｃの減速比（Ｃ／Ａ）は、数百分の１から数千分の１の減速比を実現できる。
【００２０】
【発明の実施の形態】
図１は本願第１発明に対応した第１実施形態による減速装置のギアトレインの説明図である。
図１において、本発明の減速装置は第１遊星歯車装置１０と第２遊星歯車装置２０を同一中心軸線上に配置している。第１遊星歯車装置１０は、第１太陽歯車１１、第１太陽歯車１１の周囲を自転しながら公転する第１遊星歯車１２、第１遊星歯車１２の外側に噛み合わされた第１内歯歯車１３、更に第１遊星歯車１２を回転自在（自転）に軸支してその交転を取り出す第１キャリア１４を構成される。
【００２１】
第２遊星歯車装置２０も、第２太陽歯車２１、第２遊星歯車２２、第２内歯歯車２３及び第２キャリア２４で構成される。
更に第１遊星歯車装置１０と第２遊星歯車装置２０との間には、第１太陽歯車１１と第１内歯歯車１３の歯数比（Ｚ11／Ｚ13）と第２太陽歯車２１と第２内歯歯車２３の歯数比（Ｚ21／Ｚ23）とが異なるように歯車の歯数が決められている。このような第１遊星歯車装置１０と第２遊星歯車装置２０について、図１の第１実施形態にあっては、まず第１キャリア１４と第２キャリア２４を連結し、ここから左側に入力軸１を取り出している。また第１内歯歯車１３と第２内歯歯車２３も連結され、これらはフリー状態となっている。更に第１太陽歯車１１は固定され、第２太陽歯車２１からは出力軸２が取り出されている。
【００２２】
ここで図１のように、第１太陽歯車１１の歯数をＺ11、第１遊星歯車１２の歯数をＺ12、第１内歯歯車１３の歯数をＺ13、第２太陽歯車２１の歯数をＺ21、第２遊星歯車２２の歯数をＺ22、更に第２内歯歯車２３の歯数をＺ23とすると、入力軸１の入力回転Ａと出力軸２の出力回転Ｃとの比で与えられる減速比（Ｃ／Ａ）は次のようになる。
【００２３】
【数８】

【００２４】
この（１）式の右辺から明らかなように、分子は第１太陽歯車１１と第２内歯歯車２３の歯数の乗算値（Ｚ11・Ｚ23）と第１内歯歯車１３と第２太陽歯車２１の歯数の乗算値（Ｚ13・Ｚ21）の差となることから、例えば１０以下の小さな値をとる。これに対し分母は第１内歯歯車１３と第２太陽歯車２１の歯数の乗算値（Ｚ13・Ｚ21）であり、数百オーダの大きな値となる。
【００２５】
この結果、例えば入力軸１に入力回転Ａ＝１０００ｒｐｍを入力すると、出力軸２には（１）式より逆回りに１０００分の１以上に減速された出力回転Ｃを得ることができる。
ここで図１の実施形態の具体的な数値例を挙げると次のようになる。例えば
Ｚ11＝４１
Ｚ12＝３４
Ｚ13＝１０９
Ｚ21＝３５
Ｚ22＝２９
Ｚ23＝９３
とした場合、減速比Ｃ／Ａ＝＋（１／１９０７．５）となる。また
Ｚ11＝５１
Ｚ12＝２３
Ｚ13＝９７
Ｚ21＝３１
Ｚ22＝１４
Ｚ23＝５９
とした場合、減速比Ｃ／Ａ＝−（１／１５０３．５）となる。
【００２６】
図２は、本願の第２発明に対応した減速装置の第２実施形態のギアトレインの説明図である。この第２実施形態にあっても、図１の第１実施形態と同様、第１遊星歯車装置１０と第２遊星歯車装置２０を同じ中心軸線上に配置している。このような第１遊星歯車装置１０と第２遊星歯車装置２０について第２実施形態にあっては、まず第１内歯歯車１３と第２内歯歯車２３を連結し、これについて左側に入力軸１を取り出している。
【００２７】
また第１キャリア１４と第２キャリア２４が連結され、これらはフリー状態となっている。更に第１太陽歯車１１が固定され、第２太陽歯車２１からは出力軸２が取り出されている。このような第２実施形態における入力軸１の入力回転をＢ、出力軸２の出力回転をＣとすると、減速比（Ｃ／Ｂ）は次式で与えられる。
【００２８】
【数９】

【００２９】
この（２）式の右辺から明らかなように、分子は図１の第１実施形態と同様、第１太陽歯車１１と第２内歯歯車２３の歯数の乗算値（Ｚ11・Ｚ23）から第１内歯歯車１３と第２太陽歯車２１の歯数の乗算値（Ｚ13・Ｚ21）を差し引いた値であり、１０以下の十分に小さな値となる。
これに対し分母は第１太陽歯車１１と第１内歯歯車１３の歯数の和（Ｚ11＋Ｚ13）に第２太陽歯車２１の歯数Ｚ２１を乗じた値であり、十分に大きな値をとることができる。その結果、減速比（Ｃ／Ｂ）は数百分の１から１０００分の１を越える十分に大きな減速比とすることができる。
【００３０】
図３は本願の第３発明に対応した減速装置の第３実施形態のギアトレインの説明図である。この第３実施形態にあっても、図１の実施形態と同様、第１遊星歯車装置１０と第２遊星歯車装置２０を同じ軸心線上に配列している。これに対し第３実施形態にあっては、まず第１内歯歯車１３と第２内歯歯車２３を連結して左側に入力軸１を取り出している。
【００３１】
また第１太陽歯車１１と第２太陽歯車２１を連結し、これらはフリー状態としている。更に第１キャリア１４は固定され、第２キャリア２４から出力軸２を取り出している。この図３の第３実施形態における入力軸１の入力回転Ｂと出力軸２の出力回転Ｃとの比で与えられる減速比（Ｃ／Ｂ）は次式で与えられる。
【００３２】
【数１０】

【００３３】
この（３）式の右辺から明らかなように、分子は図１及び図２の各実施形態と同様、第１太陽歯車１１と第２内歯歯車２３の歯数の乗算値（Ｚ11・Ｚ23）から第１内歯歯車１３と第２太陽歯車２１の歯数の乗算値（Ｚ13・Ｚ21）を差し引いた値であり、十分に小さな値となる。
これに対し分母は第２太陽歯車２１と第２内歯歯車２３の歯数の和（Ｚ21＋Ｚ23）に第１太陽歯車１１の歯数Ｚ11を乗じた値であり、分子に対し十分に大きな値となる。このため、（３）式で与えられる減速比（Ｃ／Ｂ）は数百分の１から１０００分の１を越える十分大きな減速比とすることができる。また図３の第３実施形態にあっては、入力軸１に対する入力回転Ｂと減速後の出力軸２の出力回転Ｃの回転方向は同一方向となっている。
【００３４】
図４は本願の第４発明に対応した減速装置の第４実施形態のギアトレインの説明図である。この第４実施形態にあっても、図１の実施形態と同様、第１遊星歯車装置１０と第２遊星歯車装置２０を同じ軸心線上に配列している。これに対し第４実施形態にあっては、まず第１キャリア１４と第２キャリア２４を連結して左側に入力軸１を取り出している。
【００３５】
また第１太陽歯車１１と第２太陽歯車２１を連結し、これらはフリー状態としている。更に第１内歯歯車１３は固定され、第２内歯歯車２３から出力軸２を取り出している。この図４の第４実施形態における入力軸１の入力回転Ａと出力軸２の出力回転Ｃとの比で与えられる減速比（Ｃ／Ａ）は次式で与えられる。
【００３６】
【数１１】

【００３７】
この（４）式の右辺から明らかなように、分母は図１から図３の各実施形態と同様、第１内歯歯車１１と第２内歯歯車２３の歯数の乗算値（Ｚ11・Ｚ23）から第１太陽歯車１３と第２太陽歯車２１の歯数の乗算値（Ｚ13・Ｚ21）を差し引いた値であり、十分に小さな値となる。
これに対し分母は第１太陽歯車１１の歯数Ｚ11に第２内歯歯車２３の歯数を乗じた値であり、分子に対して十分に大きな値となる。このため、（４）式で与えられる減速比（Ｃ／Ａ）は数百分の１から１０００分の１を越える十分大きな減速比とすることができる。
【００３８】
尚、上記の実施形態は、入力回転を減速して出力する減速装置を例にとっているが、図１〜図３における入力軸１と出力軸２の関係を逆にすれば、増速装置として利用できることはもちろんである。
また、上記の実施形態を説明する図においては、原理図であるために第１遊星歯車１２と第２遊星歯車２２を２つずつ示しているが、２つに限らず任意の数でよい。
【００３９】
【発明の効果】
以上説明してきたように本発明によれば、太陽歯車と内歯歯車との互いの歯数比が異なる第１及び第２の遊星歯車装置を同一中心軸上に配置し、２つの遊星歯車装置の内歯歯車同士は連結し、太陽歯車同士とキャリア同士についてはいずれか１つを選んで連結し、連結した組について入力軸を取り出し、連結していない組について一方を固定、他方から出力軸を取り出す構成としたことで、入力回転に対し数百から数千といった極めて高い減速比を得ることができる。
【００４０】
また遊星歯車装置であることから、小型で高トルクが実現できる。更に、必要に応じて入力回転と出力回転の方向を歯数の選択によって変えることも可能である。
更に、入力軸と出力軸が同一軸心上に配置されるため、減速装置としての製造、組立、取付等に適している。更に平歯車の組合せであることから、従来の特殊な部品を用いたハーモニックドライブ装置に比べ、低コストで実現することができる。
【図面の簡単な説明】
【図１】本発明の第１実施形態によるギアトレインの説明図
【図２】本発明の第２実施形態によるギアトレインの説明図
【図３】本発明の第３実施形態によるギアトレインの説明図
【図４】本発明の第４実施形態によるギアトレインの説明図
【図５】従来のハーモニックドライブ装置の説明図
【符号の説明】
１：入力軸
２：出力軸
１０：第１遊星歯車装置
１１：第１太陽歯車
１２：第１遊星歯車
１３：第１内歯歯車
１４：第１キャリア
２０：第２遊星歯車装置
２１：第２太陽歯車
２２：第２遊星歯車
２３：第２内歯歯車
２４：第２キャリア[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reduction gear device that uses a double planetary gear device to obtain a large reduction gear ratio.
[0002]
[Prior art]
Conventionally, for example, a harmonic drive device as shown in FIG. 5 is known as a reduction device for obtaining a large reduction ratio exceeding 1/100.
In FIG. 5A, the harmonic drive device includes a wave generator 101, a flex spline 102, and a circular spline 103. In the wave generator 101, a thin ball bearing is fitted on the outer periphery of the elliptical cam, and the whole is elliptical. The flexspline 102 is a thin metal elastic body having a cup shape, and a gear is engraved on the outer periphery of the opening of the cup.
[0003]
Further, the circular spline 103 is a rigid ring, and a gear having the same size as that of the flex spline 102 is engraved on the inner circumference, and the number of teeth is two more than that of the flex spline 102. The flex spline 102 is bent into an elliptical state by the wave generator 101, and the gear is engaged with the Circa spline 103 at the long axis portion of the ellipse, and the gear is completely separated at the short shaft portion.
[0004]
When the circular spline 103 is fixed in FIG. 5 (A) and the input rotation is transmitted to the wave generator 101 and rotated clockwise as shown in FIG. 5 (B), the flex spline 102 is elastically deformed. The gear meshing position with the spline 103 moves sequentially.
As shown in FIG. 5C, when the wave generator 101 is rotated once, the flex sprune 102 has two fewer teeth than the circular spun 103, and thus is counterclockwise opposite to the rotation direction of the wave generator 101. The movement of the flexspline 102 is taken out as an output.
[0005]
[Problems to be solved by the invention]
However, such conventional harmonic drive devices are expensive because they require specially shaped parts, and there is a problem that the reduction ratio is in principle about 1/200. .
The present invention has been made in view of such conventional problems, and is inexpensive in that a high reduction ratio of one hundredth to one thousandth can be easily obtained by using a double planetary gear. An object is to provide a reduction gear.
[0006]
[Problems to be solved by the invention]
In order to achieve this object, the speed reducer of the present invention is configured as follows. First, a reduction gear of the present invention includes a first sun gear, a first internal gear, a plurality of first planetary gears meshed between the first sun gear and the first internal gear, and a plurality of first planetary gears. A first planetary gear device having a first carrier that connects the rotation shafts of the gears and extracts the revolutions of the plurality of first planetary gears; a second sun gear; a second internal gear; a second sun gear; A plurality of second planetary gears meshed with each other between the internal gears, and a second carrier for connecting the rotation shafts of the plurality of second planetary gears to take out revolutions of the plurality of second planetary gears; The second sun gear and the second internal gear have a gear number ratio different from that of the first sun gear and the first internal gear, and are arranged on the same central axis as the first planetary gear device. It is composed of a planetary gear device.
[0007]
In such a double planetary gear having the first planetary gear device and the second planetary gear device, in the first invention of the present application, the first carrier and the second carrier are the first planetary gear device and the second planetary gear. The revolving shafts are aligned and connected between the devices. Further, the first carrier takes out the input shaft on the opposite side to the second planetary gear device side, and the first internal gear and the second internal gear are connected and free. The first sun gear is fixed, and the output shaft is further taken out from the second sun gear.
[0008]
According to the first invention, the number of teeth of the first sun gear is Z11, the number of teeth of the first planetary gear is Z12, the number of teeth of the first internal gear is Z13, the number of teeth of the second sun gear is Z21, and the second planetary gear. When the number of gear teeth is Z22 and the number of teeth of the second internal gear is Z23, the reduction ratio (C / A) between the input rotation A of the input shaft and the output rotation C of the output shaft is
[0009]
[Expression 4]

[0010]
Given in. In this case, the right-side denominator takes a large value by multiplication of the number of teeth, and the right-side numerator takes a difference in the number-of-tooth multiplication result. Therefore, it takes a smaller value and the reduction ratio (C / A) of the output rotation C to the input rotation A Can realize a reduction ratio of one hundredth to several thousandth. The second invention of the present application relates to a double planetary gear having the same first planetary gear device and the second planetary gear device as in the first invention, and connects the first internal gear and the second internal gear to take out the input shaft. The first carrier and the second carrier are free by connecting the first planetary gear device and the second planetary gear device with their revolving shafts aligned with each other , fixing the first sun gear, and further outputting from the second sun gear. The shaft is taken out.
[0011]
In this case, the reduction ratio (C / B) between the input rotation B of the input shaft and the output rotation C of the output shaft is
[0012]
[Equation 5]

[0013]
Given in.
In this case, the right-side denominator takes a large value by multiplication of the number of teeth, and the right-side numerator takes a difference in the number-of-tooth multiplication result. Therefore, it takes a smaller value and the reduction ratio (C / A) of the output rotation C to the input rotation A Can realize a reduction ratio of one hundredth to several thousandth.
The third invention of the present application relates to a double planetary gear device having the same first planetary gear device and the second planetary gear device as in the first invention, and connects the first internal gear and the second internal gear to connect the input shaft. The first sun gear and the second sun gear are connected and freed, the first carrier is fixed, and the output shaft is taken out from the second carrier of the second planetary gear.
[0014]
In this case, the reduction ratio (C / B) between the input rotation B of the input shaft and the output rotation C of the output shaft is
[0015]
[Formula 6]

[0016]
Given in. Again, taking a large value right denominator by multiplication of the number of teeth, since the right molecule of the difference number of teeth multiplied results, take a smaller value, the reduction ratio of the output rotation C with respect to the input rotation B (C / B ) Can realize a reduction ratio of one hundredth to several thousandth. The third invention of the present application is a double planetary gear having the same first planetary gear device and the second planetary gear device as in the first invention. The first carrier and the second carrier are the first planetary gear device and the second planetary gear device. Between the first carrier and the second planetary gear device side, the input shaft is taken out on the opposite side to the second planetary gear device side, and the first sun gear and the second sun gear are connected to be free, The first internal gear is fixed, and the output shaft is further taken out from the second internal gear.
[0017]
In this case, the reduction ratio (C / A) between the input rotation A of the input shaft and the output rotation C of the output shaft is
[0018]
[Expression 7]

[0019]
Given in.
Also in this case, the right-side denominator takes a large value by multiplication of the number of teeth, and the right-side numerator has a difference in the number-of-tooth multiplication result. Therefore, it takes a smaller value and the reduction ratio (C / A) of the output rotation C to the input rotation A ) Can realize a reduction ratio of one hundredth to several thousandth.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an explanatory diagram of a gear train of a reduction gear according to a first embodiment corresponding to the first invention of the present application.
In FIG. 1, the speed reducer of the present invention has a first planetary gear device 10 and a second planetary gear device 20 arranged on the same central axis. The first planetary gear device 10 includes a first sun gear 11, a first planetary gear 12 that revolves around the first sun gear 11, and a first internal gear 13 that meshes with the outside of the first planetary gear 12. In addition, a first carrier 14 is constructed in which the first planetary gear 12 is pivotally supported (rotated) to take out its rotation.
[0021]
The second planetary gear device 20 also includes a second sun gear 21, a second planetary gear 22, a second internal gear 23, and a second carrier 24.
Further, between the first planetary gear device 10 and the second planetary gear device 20, the gear ratio (Z11 / Z13) of the first sun gear 11 and the first internal gear 13, the second sun gear 21 and the second The number of teeth of the gear is determined so that the gear ratio (Z21 / Z23) of the internal gear 23 is different. With regard to the first planetary gear device 10 and the second planetary gear device 20 as described above, in the first embodiment of FIG. 1, first, the first carrier 14 and the second carrier 24 are first connected, and the input shaft extends from here to the left side. 1 is taken out. Moreover, the 1st internal gear 13 and the 2nd internal gear 23 are also connected, and these are in a free state. Further, the first sun gear 11 is fixed, and the output shaft 2 is taken out from the second sun gear 21.
[0022]
Here, as shown in FIG. 1, the number of teeth of the first sun gear 11 is Z11, the number of teeth of the first planetary gear 12 is Z12, the number of teeth of the first internal gear 13 is Z13, and the number of teeth of the second sun gear 21. Is Z21, the number of teeth of the second planetary gear 22 is Z22, and the number of teeth of the second internal gear 23 is Z23, it is given by the ratio of the input rotation A of the input shaft 1 and the output rotation C of the output shaft 2. The reduction ratio (C / A) is as follows.
[0023]
[Equation 8]

[0024]
As is apparent from the right side of the equation (1), the numerator is the product of the number of teeth of the first sun gear 11 and the second internal gear 23 (Z11 / Z23), the first internal gear 13 and the second sun gear. Since this is the difference in the multiplication value (Z13 · Z21) of the number of teeth of 21, for example, a small value of 10 or less is taken. On the other hand, the denominator is a multiplication value (Z13 · Z21) of the number of teeth of the first internal gear 13 and the second sun gear 21, which is a large value on the order of several hundreds.
[0025]
As a result, for example, when the input rotation A = 1000 rpm is input to the input shaft 1, the output rotation C can be obtained on the output shaft 2 that is decelerated more than 1/1000 in the reverse direction from the equation (1).
Here, specific numerical examples of the embodiment of FIG. 1 are as follows. For example, Z11 = 41
Z12 = 34
Z13 = 109
Z21 = 35
Z22 = 29
Z23 = 93
In this case, the reduction ratio C / A = + (1 / 1907.5). Z11 = 51
Z12 = 23
Z13 = 97
Z21 = 31
Z22 = 14
Z23 = 59
In this case, the reduction ratio C / A = − (1 / 1503.5).
[0026]
FIG. 2 is an explanatory diagram of a gear train of a second embodiment of the reduction gear device corresponding to the second invention of the present application. Even in the second embodiment, the first planetary gear device 10 and the second planetary gear device 20 are arranged on the same central axis as in the first embodiment of FIG. In the second embodiment of the first planetary gear device 10 and the second planetary gear device 20 as described above, the first internal gear 13 and the second internal gear 23 are first connected, and the input shaft is connected to the left side of the first internal gear 13. 1 is taken out.
[0027]
Moreover, the 1st carrier 14 and the 2nd carrier 24 are connected, and these are in a free state. Further, the first sun gear 11 is fixed, and the output shaft 2 is taken out from the second sun gear 21. Assuming that the input rotation of the input shaft 1 in the second embodiment is B and the output rotation of the output shaft 2 is C, the reduction ratio (C / B) is given by the following equation.
[0028]
[Equation 9]

[0029]
As is apparent from the right side of the equation (2), the numerator is calculated from the multiplication value (Z11 · Z23) of the number of teeth of the first sun gear 11 and the second internal gear 23 as in the first embodiment of FIG. The value obtained by subtracting the multiplication value (Z13 · Z21) of the number of teeth of the first internal gear 13 and the second sun gear 21 is a sufficiently small value of 10 or less.
On the other hand, the denominator is a value obtained by multiplying the sum of the number of teeth of the first sun gear 11 and the first internal gear 13 (Z11 + Z13) by the number of teeth Z21 of the second sun gear 21, and can take a sufficiently large value. it can. As a result, the reduction ratio (C / B) can be set to a sufficiently large reduction ratio exceeding one hundredth to one thousandth.
[0030]
FIG. 3 is an explanatory diagram of a gear train of a third embodiment of a reduction gear corresponding to the third invention of the present application. Even in the third embodiment, the first planetary gear device 10 and the second planetary gear device 20 are arranged on the same axis as in the embodiment of FIG. On the other hand, in the third embodiment, first, the first internal gear 13 and the second internal gear 23 are connected to take out the input shaft 1 on the left side.
[0031]
Moreover, the 1st sun gear 11 and the 2nd sun gear 21 are connected, and these are made into the free state. Further, the first carrier 14 is fixed, and the output shaft 2 is taken out from the second carrier 24. The reduction ratio (C / B) given by the ratio between the input rotation B of the input shaft 1 and the output rotation C of the output shaft 2 in the third embodiment of FIG. 3 is given by the following equation.
[0032]
[Expression 10]

[0033]
As is apparent from the right side of the equation (3), the numerator is the multiplication value (Z11 · Z23) of the number of teeth of the first sun gear 11 and the second internal gear 23 as in the embodiments of FIGS. Is a value obtained by subtracting the multiplication value (Z13 · Z21) of the number of teeth of the first internal gear 13 and the second sun gear 21, and is a sufficiently small value.
On the other hand, the denominator is a value obtained by multiplying the sum of the number of teeth of the second sun gear 21 and the second internal gear 23 (Z21 + Z23) by the number of teeth Z11 of the first sun gear 11, which is sufficiently large for the numerator. Become. For this reason, the reduction ratio (C / B) given by the expression (3) can be set to a sufficiently large reduction ratio exceeding one hundredth to one thousandth. In the third embodiment of FIG. 3, the rotation direction of the input rotation B with respect to the input shaft 1 and the output rotation C of the output shaft 2 after deceleration are the same direction.
[0034]
FIG. 4 is an explanatory diagram of a gear train of a fourth embodiment of a reduction gear device corresponding to the fourth invention of the present application. In the fourth embodiment as well, the first planetary gear device 10 and the second planetary gear device 20 are arranged on the same axis as in the embodiment of FIG. On the other hand, in the fourth embodiment, first, the first carrier 14 and the second carrier 24 are connected, and the input shaft 1 is taken out on the left side.
[0035]
Moreover, the 1st sun gear 11 and the 2nd sun gear 21 are connected, and these are made into the free state. Further, the first internal gear 13 is fixed, and the output shaft 2 is taken out from the second internal gear 23. The reduction ratio (C / A) given by the ratio between the input rotation A of the input shaft 1 and the output rotation C of the output shaft 2 in the fourth embodiment of FIG. 4 is given by the following equation.
[0036]
[Expression 11]

[0037]
As is clear from the right side of the equation (4), the denominator is the multiplication value (Z11 · Z23) of the number of teeth of the first internal gear 11 and the second internal gear 23, as in the embodiments of FIGS. ) Is a value obtained by subtracting the multiplication value (Z13 · Z21) of the number of teeth of the first sun gear 13 and the second sun gear 21, which is a sufficiently small value.
On the other hand, the denominator is a value obtained by multiplying the number of teeth Z11 of the first sun gear 11 by the number of teeth of the second internal gear 23, and is a sufficiently large value for the numerator. For this reason, the reduction ratio (C / A) given by the equation (4) can be a sufficiently large reduction ratio exceeding one hundredth to one thousandth.
[0038]
In the above embodiment, the speed reduction device that decelerates and outputs the input rotation is taken as an example. However, if the relationship between the input shaft 1 and the output shaft 2 in FIGS. Of course you can.
Moreover, in the figure explaining said embodiment, since it is a principle figure, the 1st planetary gear 12 and the 2nd planetary gear 22 are shown two each, but it is not restricted to two but arbitrary numbers may be sufficient.
[0039]
【The invention's effect】
As described above, according to the present invention, the first and second planetary gear devices having different gear ratios of the sun gear and the internal gear are arranged on the same central axis, and two planetary gear devices are provided. The internal gears are connected to each other, one of the sun gears and the carriers is selected and connected, the input shaft is taken out of the connected set, one of the unconnected sets is fixed, and the output shaft from the other is fixed With this configuration, it is possible to obtain a very high reduction ratio of several hundred to several thousand with respect to the input rotation.
[0040]
Further, since it is a planetary gear device, it is small and can realize high torque. Furthermore, the direction of input rotation and output rotation can be changed by selecting the number of teeth as required.
Furthermore, since the input shaft and the output shaft are arranged on the same axis, it is suitable for manufacturing, assembling and mounting as a reduction gear. Furthermore, since it is a combination of spur gears, it can be realized at a lower cost than a conventional harmonic drive device using special parts.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a gear train according to a first embodiment of the present invention. FIG. 2 is an explanatory diagram of a gear train according to a second embodiment of the present invention. FIG. 3 is an explanatory diagram of a gear train according to a third embodiment of the present invention. FIG. 4 is an explanatory diagram of a gear train according to a fourth embodiment of the present invention. FIG. 5 is an explanatory diagram of a conventional harmonic drive device.
1: input shaft 2: output shaft 10: first planetary gear unit 11: first sun gear 12: first planetary gear 13: first internal gear 14: first carrier 20: second planetary gear unit 21: second Sun gear 22: second planetary gear 23: second internal gear 24: second carrier

Claims

The first sun gear, the first internal gear, the plurality of first planetary gears meshed between the first sun gear and the first internal gear, and the rotation axes of the plurality of first planetary gears are mutually connected. A first planetary gear device comprising a first carrier coupled to take out revolutions of a plurality of first planetary gears;
The second sun gear, a second internal gear, said second sun gear and a plurality of second planetary gears that mesh with each between the second internal gear, and the rotation axis of the plurality of second planetary gears to one another A second carrier connected to take out revolutions of a plurality of second planetary gears, and having a gear ratio between the first sun gear and the first internal gear different from that of the second sun gear and the second internal gear. And a second planetary gear unit disposed on the same central axis as the first planetary gear unit,
The first carrier and the second carrier are connected to each other with the revolving shaft aligned between the first planetary gear device and the second planetary gear device, and the first carrier is input to the opposite side to the second planetary gear device side. Deceleration characterized in that the shaft is taken out, the first internal gear and the second internal gear are connected to be free, the first sun gear is fixed, and the output shaft is taken out from the second sun gear. apparatus.

2. The reduction gear according to claim 1, wherein the number of teeth of the first sun gear is Z11, the number of teeth of the first planetary gear is Z12, the number of teeth of the first internal gear is Z13, and the number of teeth of the second sun gear is Z21. When the number of teeth of the second planetary gear is Z22 and the number of teeth of the second internal gear is Z23, the reduction ratio (C / A) between the input rotation A and the output rotation C of the input shaft is

The speed reducer characterized by being.

The first sun gear, the first internal gear, the plurality of first planetary gears meshed between the first sun gear and the first internal gear, and the rotation axes of the plurality of first planetary gears are mutually connected. A first planetary gear device comprising a first carrier coupled to take out revolutions of a plurality of first planetary gears;
The second sun gear, a second internal gear, said second sun gear and a plurality of second planetary gears that mesh with each between the second internal gear, and the rotation axis of the plurality of second planetary gears to one another A second carrier connected to take out revolutions of a plurality of second planetary gears, and having a gear ratio between the first sun gear and the first internal gear different from that of the second sun gear and the second internal gear. And a second planetary gear unit disposed on the same central axis as the first planetary gear unit,
The first internal gear and the second internal gear are connected to take out an input shaft, and the first carrier and the second carrier have their revolving axes aligned between the first planetary gear device and the second planetary gear device. The reduction gear device is characterized in that the first sun gear is fixed and the output shaft is taken out from the second sun gear.

4. The reduction gear according to claim 3 , wherein the number of teeth of the first sun gear is Z11, the number of teeth of the first planetary gear is Z12, the number of teeth of the first internal gear is Z13, and the number of teeth of the second sun gear is Z21. When the number of teeth of the second planetary gear is Z22 and the number of teeth of the second internal gear is Z23, the reduction ratio (C / B) between the input rotation B and the output rotation C of the input shaft is

The speed reducer characterized by being.

The first sun gear, the first internal gear, the plurality of first planetary gears meshed between the first sun gear and the first internal gear, and the rotation axes of the plurality of first planetary gears are mutually connected. A first planetary gear device comprising a first carrier coupled to take out revolutions of a plurality of first planetary gears;
The second sun gear, a second internal gear, said second sun gear and a plurality of second planetary gears that mesh with each between the second internal gear, and the rotation axis of the plurality of second planetary gears to one another A second carrier connected to take out revolutions of a plurality of second planetary gears, and having a gear ratio between the first sun gear and the first internal gear different from that of the second sun gear and the second internal gear. And a second planetary gear unit disposed on the same central axis as the first planetary gear unit,
The first carrier and the second carrier are connected to each other with the revolving shaft aligned between the first planetary gear device and the second planetary gear device, and the first carrier is input to the opposite side to the second planetary gear device side. The shaft is taken out, the first sun gear and the second sun gear are connected to be free, the first internal gear is fixed, and the output shaft is taken out from the second internal gear. Reducer.

6. The reduction gear according to claim 5, wherein the number of teeth of the first sun gear is Z11, the number of teeth of the first planetary gear is Z12, the number of teeth of the first internal gear is Z13, and the number of teeth of the second sun gear is Z21. When the number of teeth of the second planetary gear is Z22 and the number of teeth of the second internal gear is Z23, the reduction ratio (C / A ) between the input rotation A and the output rotation C of the input shaft is

The speed reducer characterized by being.