JPS5899549A - Differential planet rotary type reduction gear - Google Patents

Abstract

PURPOSE:To provide a compact reduction gear with infinitely variable reduction ratio by mounting a pair of reduction gears respectively provided planet rotary mechanisms and having different reduction ratios on different diameter portions of a same stepped rotary input shaft to utilize the difference between the diameters of the shaft. CONSTITUTION:An input shaft 1 is a stepped one provided with different diameter portions 1A, 1B and journalled by a support 3 provided with a bearing 5. A plurality of bearings 9 are arranged in equal intervals on said larger diameter portion 1A and respectively fitted on a plurality of pins 7 planted on the support 3, while an annular body 11 coaxial with the shaft 1 is arranged around the outer periphery of the bearings 9. Also, a plurality of bearings 13 similar to the bearings 9 are arranged to make rolling contact with the smaller diameter portion 1B. Then, the dameter r5 of the bearing 13 is larger than the diameter r3 of the bearing 9 and the bearings 13 contact closely the annular body 11. Thus, the large and small diameter portions 1A, 1B can be respectively formed with first and second planet rotary type reduction gear mechanisms 10, 20.

Description

【発明の詳細な説明】 （１）　　発明の技術分野 本発明は遊星回転式の差動形減速装置、とくに小型の駆
動部をもって大きなトルクを得る必要がある、ｅＮえば
ロボット・アーム等の装置に適用しく１） て好適な減速機構に係る。DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention is applicable to planetary rotation type differential speed reducers, especially devices such as eN robots and arms that need to obtain large torque with a small drive unit. Applicably, 1) relates to a suitable speed reduction mechanism.

１２）技術の背景 例えばロボット・アームの駆動においては一般に精々数
ｒｐｓ程度の比較的低速（低回転数）で高出力の得られ
るアクチーエータが必要となる。従って、一般に１、寸
アームの駆動源として電動モータが使用されるが、その
場合には歯車列減速機、ウオームギヤ減速機あるいはハ
ーモニックドライブ減速機を用いて高出力を得るように
している。12) Background of the Technology For example, in driving a robot arm, an actuator that can provide high output at a relatively low speed (low rotational speed) of at most several rps is generally required. Therefore, an electric motor is generally used as a drive source for the 1.5-inch arm, but in that case, a gear train reducer, a worm gear reducer, or a harmonic drive reducer is used to obtain high output.

ｔ３１　　従来技術と問題点 しかしながら、従来のこれら減速機はいずれも減速比は
歯数比によって決定されるために大きな減速比が得られ
ないという問題があった。また大きな減速比を得るため
には歯車の数を増大しなければならず、いきかい減速機
全体が■雑犬形化することになり、例えば数百外の１と
いった大きな減速比を得ることは実際上不可能に近かっ
た。t31 Prior Art and Problems However, all of these conventional speed reducers have the problem that a large speed reduction ratio cannot be obtained because the speed reduction ratio is determined by the tooth number ratio. In addition, in order to obtain a large reduction ratio, the number of gears must be increased, and the entire speed reduction gear becomes a dog-like shape. It was practically impossible.

（４）発明の目的 本発明の目的は実質上無限に近い減速比の得られる小型
でかつ簡易の減速装置を提供することに１゛９） より上述の如き従来技術の問題点を解消することにある
。(4) Purpose of the Invention The purpose of the present invention is to provide a small and simple speed reduction device that can obtain a virtually infinite speed reduction ratio. It is in.

１５）発明の構成 上述の目的を達成するために本発明によれば、各々が遊
星回転機構を有する減速比の異なる一対の減速機全同一
の段付回転入力軸の異径部に取付け、これら異径部の径
差により大きな減速比を得るようにした差動形減速装置
が提供される。15) Structure of the Invention In order to achieve the above-mentioned object, according to the present invention, a pair of reducers each having a planetary rotation mechanism and having different reduction ratios are all attached to different diameter portions of the same stepped rotation input shaft. A differential speed reduction device is provided in which a large speed reduction ratio is obtained by a diameter difference between different diameter portions.

１６）発明の実施例 以下、本発明の実施例を図面に従って説明する。16) Examples of the invention Embodiments of the present invention will be described below with reference to the drawings.

入力軸１は異径部ＩＡ、ＩＢを有する段付軸である。大
径部１人の直径及び半径を夫々Ｄ１．ｒ１及び小径部１
ＢのＩＫ径及び半径を夫々Ｄ２．ｒ２とする。入力軸１
はベアリング５を有する保持器３により回転自在に支承
される。軸１の大径部１人には例えば３個のベアリング
９が１２０°　間隔で配置される。保持器乙には軸１と
平行に延びる軸ピン７が１２０°　間隔で突設され、こ
れら軸ピン７に対応のベアリング９が回転自在に嵌合せ
しめられる。ベアリング９の外周には軸１と同軸的に環
体１１が配設される。従ってベアリング９け軸の大径部
ＩＡ、！：ＩＪ体１１との間でころが如接触する。陶、
環体１１の外周からそれ自体公知の例えばくさび式与圧
機構を介して半径方向の与圧力を付与しベアリング９、
環体１１及び軸１の間の密接性を強くするのが好ましい
。The input shaft 1 is a stepped shaft having different diameter portions IA and IB. The diameter and radius of one large diameter section are respectively D1. r1 and small diameter part 1
The IK diameter and radius of B are respectively D2. Let it be r2. Input shaft 1
is rotatably supported by a retainer 3 having a bearing 5. For example, three bearings 9 are arranged on one large diameter portion of the shaft 1 at intervals of 120°. Axle pins 7 extending parallel to the shaft 1 are protruded from the retainer B at 120° intervals, and bearings 9 corresponding to these axle pins 7 are rotatably fitted. An annular body 11 is disposed on the outer periphery of the bearing 9 coaxially with the shaft 1. Therefore, the large diameter part IA of the 9-shaft bearing! : The rollers come into contact with the IJ body 11. Pottery,
A radial pressurizing force is applied from the outer periphery of the ring body 11 via a known wedge type pressurizing mechanism, for example, to the bearing 9,
It is preferable to increase the closeness between the ring body 11 and the shaft 1.

一方、川１１の小径部１Ｂ上にもベアリング９と同様に
３個のベアリング１３がころがり接触せしめられる。ベ
アリング１３の径ｒ５　　はベアリング９の径ｒ３　　
よりも太き（（ｒｓ＞ｒｓ）、ベアリング１３も環体１
１の内周に密接するようになっている。出力回転体１５
はベアリング１９を介して軸１に回転自在に軸支され、
保持器３の軸ピン７と同様の３個の軸ビン１７を有する
。この軸ビンｊ７ｊ４１２０°　間隔に配置され、これ
らの軸ビン１７に対応のベアリング１３が回転自在に嵌
合せしめられる。On the other hand, three bearings 13 are also brought into rolling contact with the small diameter portion 1B of the river 11, similar to the bearing 9. The diameter r5 of the bearing 13 is the diameter r3 of the bearing 9.
((rs>rs), bearing 13 is also thicker than ring body 1
It is arranged to be in close contact with the inner circumference of 1. Output rotating body 15
is rotatably supported on the shaft 1 via a bearing 19,
It has three shaft pins 17 similar to the shaft pins 7 of the retainer 3. These shaft pins 17 are arranged at intervals of j7j4120°, and bearings 13 corresponding to these shaft pins 17 are rotatably fitted.

斯くして軸１の大径部１人には第１の遊星回転式減速機
構が形成され、他方、軸１の小径部１Ｂには第２の遊星
回転式減速機構が形成される。第１遊星回転式減速機構
においては軸１の大径部１人が太陽回転子、ベアリング
９が遊星回転子に夫々相当し、第２遊星回転式減速機構
においては軸１の小径部ＩＢ−Ａｆ太陽回転子、ベアリ
ング１３が遊樽回転子に夫々相当する。Thus, a first planetary rotary speed reduction mechanism is formed in the large diameter portion 1B of the shaft 1, and a second planetary rotation speed reduction mechanism is formed in the small diameter portion 1B of the shaft 1. In the first planetary rotary reduction mechanism, the large diameter portion of the shaft 1 corresponds to the sun rotor, and the bearing 9 corresponds to the planetary rotor, and in the second planetary rotation reduction mechanism, the small diameter portion IB-Af of the shaft 1 corresponds to the sun rotor. The sun rotor and the bearing 13 each correspond to a play barrel rotor.

さて上述のｐ口き遊星回転機構にさいて、保持器３を固
定として考えると入力＠１の回転角θ１　と環体１１の
回転角θ４　とは相対すべりがないものとして周知の如
く次式を満足する。Now, in the above-mentioned P-hole planetary rotation mechanism, if the cage 3 is assumed to be fixed, the rotation angle θ1 of the input @1 and the rotation angle θ4 of the ring body 11 are calculated by the following equation as well-known assuming that there is no relative slip. be satisfied.

１ θ４＝−−θ１・・・書１拳・（１） ４ 但し、ｒａ　＝環体１１の内周半径 次に環体１１を固定として考えると同様にして、入力軸
１の回転角θ１　と、ベアリング１３を支える出力回転
体１５の回転角０６′とは次式の関係にある。1 θ4=--θ1...Book 1 fist・(1) 4 However, ra = inner radius of the ring body 11 Next, if the ring body 11 is considered fixed, similarly, the rotation angle θ1 of the input shaft 1 and , and the rotation angle 06' of the output rotating body 15 that supports the bearing 13 have the following relationship.

ｒａ　＋？”２ また入力軸１を固定とし、環体１１を（１）式のθ４だ
け回転せしめた場合の出力回転体１５の回転角θ６は、
（１）式を用いて ｒａ　＋　ｒ２ したがって最終的な出力回転体１５の回転角θ６は、０
６′とθ６“の合成となり、 ｒ４＋ｒ２　　　　　γ４＋ｒ２ と表わされる。これより減速比には ｒ２　−　９’１ となる。ra+? 2. Also, when the input shaft 1 is fixed and the ring body 11 is rotated by θ4 in equation (1), the rotation angle θ6 of the output rotating body 15 is:
Using equation (1), ra + r2 Therefore, the final rotation angle θ6 of the output rotating body 15 is 0
6' and θ6", and is expressed as r4+r2 γ4+r2. From this, the reduction ratio becomes r2 - 9'1.

従って、ｒｌ〉τ２とすると各回転体の回転方向は第１
図に矢印で示す如くなる。Therefore, if rl>τ2, the rotational direction of each rotating body is the first
It will look like the arrow in the figure.

第（４）式から明らかな如＜ｒａ　　を一定とすれば減
速比にはＴ２−τ１の大きさ即ち、軸１の小径部１Ｂと
大径部１人の差によって決定され、従って小径部と大径
部の寸法を適当に選定することによって自由に減速比を
変えることができる。As is clear from Equation (4), if <ra is constant, the reduction ratio is determined by the magnitude of T2-τ1, that is, the difference between the small diameter section 1B and the large diameter section 1 of the shaft 1. By appropriately selecting the dimensions of the large diameter portion, the reduction ratio can be freely changed.

Ｋはｒ２−　ｒｌが小さくなる程大きくなるので、τ２
とｒｌ　の差を眼力なく小さくすることによりＫを理論
上無限大にすることができる。伺、＝２＝ｒｉとなった
ときには環体１１と軸１の回転は完全に相殺され従って
ベアリング１３は同一位置で空転するだけとなり出力回
転体１５は回転し２ない。Since K increases as r2−rl becomes smaller, τ2
Theoretically, K can be made infinite by reducing the difference between and rl without visual acuity. When ri=2=ri, the rotations of the ring body 11 and the shaft 1 are completely offset, so the bearing 13 simply idles at the same position and the output rotating body 15 does not rotate.

以上の説明において軸１の大径部１Ａ、小径部１Ｂ、に
外周歯を形成し、かつ環体１１に内周歯を形成し、そし
てベアリング９，１３をこれら内外周歯にかみ合う転位
歯車とすることにより完全な遊星歯車機構とすることも
勿論可能である。但し、歯車の場合にはバラクララシー
が伴うので図示実施例の如きころがり接触タイプの方が
好ましい。In the above description, outer teeth are formed on the large diameter portion 1A and small diameter portion 1B of the shaft 1, inner teeth are formed on the ring body 11, and the bearings 9 and 13 are arranged as shifted gears that mesh with these inner and outer teeth. Of course, it is also possible to create a complete planetary gear mechanism by doing so. However, in the case of gears, a rolling contact type as shown in the illustrated embodiment is preferable since it involves balaclarity.

まだ、図示の実施例では遊星ベアリング９，１３の径ｒ
３　、　ｒ５を相異ならしめ（ｒ３＜ｒ５）、同一の環
体１１に内接するようにしたが、これとは逆に第５図に
示す如く遊星ベアリング９’、　１５’の径を同一にし
かつ環体１１′を段付の内径としても全く同様の効果が
得られるということは理解されよう。この場合、減速比
は ｔ’　２−−　ｒｌ ４ となる。伺、入力軸１０大径部１人及び小径部１Ｂ以外
にも入力軸１には各回転子の軸方白抜は止め等の目的で
段付き部が形成されているが、大径部ＩＡ、小径部１Ｂ
以外の段付き部は本発明の減速機としての機能には全く
無関係である。However, in the illustrated embodiment, the diameter r of the planetary bearings 9, 13
3. The diameters of the planetary bearings 9' and 15' are made the same and the diameters of the planetary bearings 9' and 15' are made the same as shown in FIG. It will be understood that exactly the same effect can be obtained if the ring body 11' has a stepped inner diameter. In this case, the reduction ratio becomes t' 2 - rl 4 . In addition to the large diameter part 1B and the small diameter part 1B of the input shaft 10, the input shaft 1 is also provided with stepped parts for the purpose of stopping the axial blank areas of each rotor. , small diameter section 1B
The stepped portions other than the above are completely unrelated to the function of the reduction gear of the present invention.

（７）発明の効果 以上に記載した如く本発明によれば、役付軸部の異径部
の径差を小さくすることにより減速比を実質上無限に大
きくできる簡易構造の差動形の遊星回転式減速装置が得
られるものである。(7) Effects of the Invention As described above, according to the present invention, the differential type planetary rotation having a simple structure allows the reduction ratio to be virtually infinitely increased by reducing the diameter difference between the different diameter portions of the useful shaft portion. A type speed reduction device is obtained.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明に係る減速装置の分解錯視図、第２図は
第１の遊星回転式減速機部の軸方向正面図、第３図は第
２の遊星回転式減速機部の軸方向正面図、第４図は本発
明の減速装置の展開横断面図、第５図は本発明の別の実
施例を示す要部図。 １・・・・入力軸、　　１人・・・・大径部、１Ｂ・・
・・小径部、　　３・・・・保持器、９．１３　・・ｅ
ＩＩ遊星ベアリング、１０・・・・第１遊星回転式減速
機構、１１・・・・環体、　　１５・・・・出力回転体
、２０・・・・第２遊星歯車式減速機構。 特許出願人 富士通株式会社 特許出願代理人 弁理士　青　木　　　朗 弁理士西舘和之 弁理士内田幸男 弁理士　山　口　昭　之 く− 粧 ＼ シー、　　　日 ♀　　　さ）−ｓFIG. 1 is an exploded illusion diagram of a speed reduction device according to the present invention, FIG. 2 is an axial front view of a first planetary rotary reducer section, and FIG. 3 is an axial direction view of a second planetary rotary speed reducer section. FIG. 4 is a front view, FIG. 4 is a developed cross-sectional view of the reduction gear device of the present invention, and FIG. 5 is a main part diagram showing another embodiment of the present invention. 1...Input shaft, 1 person...Large diameter section, 1B...
...Small diameter part, 3...Cage, 9.13...e
II planetary bearing, 10...first planetary rotary reduction mechanism, 11...ring body, 15...output rotating body, 20...second planetary gear reduction mechanism. Patent applicant Fujitsu Ltd. Patent application representative Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Yukio Uchida Patent attorney Akira Yamaguchi

Claims (1)

【特許請求の範囲】[Claims] 異径部を有する段付人力軸の大径部（または小径部）周
囲に第１の遊星回転子を介して回転自在に環体を同軸的
に配置して成る￥１の遊星回転式減速機構と、上記入力
軸の小径部（または大径部〕周囲に該入力軸小径部（ま
たは大径部）と上記環体との間に配置される第２の遊星
回転子を介して出力回転体を回転自在に軸支して成る第
２の遊星回転式減速機溝とを有し、上記面域速機構の減
速比を相異ならしめることにより入力軸の回転を出力回
転体に減速して伝達し得るようＫしたことを特徴とする
差＠遊星回転式・減速装置。A planetary rotary speed reduction mechanism for ¥1 consisting of a ring body coaxially arranged around the large diameter part (or small diameter part) of a stepped human-powered shaft having different diameter parts so as to be freely rotatable via a first planetary rotor. and an output rotating body via a second planetary rotor disposed around the small diameter part (or large diameter part) of the input shaft between the small diameter part (or large diameter part) of the input shaft and the ring body. and a second planetary rotary speed reducer groove rotatably supported by the shaft, and by making the reduction ratios of the area speed mechanisms different, the rotation of the input shaft is reduced and transmitted to the output rotating body. This is a planetary rotary type reduction gear that is characterized by being K-shaped to make it possible to do so.