200900605 九、發明說明 【發明所屬之技術領域】 本發明是偏心擺動減速裝置。 【先前技術】 具備以下構件的偏心擺動減速裝置（譬如，請參考專 利文獻1 )已廣爲大眾所熟知：太陽旋轉體；和偏心體軸 驅動體，該偏心體軸驅動體是藉由上述太陽旋轉體而旋轉 ;和偏心體軸，該偏心體軸是與該偏心體軸驅動體一體地 旋轉；和至少2個的擺動體，該至少2個的擺動體是配置 於該偏心體軸之軸方向的兩側，並利用該偏心體軸而擺動 旋轉；及內接齒輪，上述擺動體分別內接於該內接齒輪。 此外，相同的申請人已針對該專利文獻1之構造提出 一種改良的構造。 第4圖、第5圖中顯示上述經改良的偏心擺動減速裝 置。 該偏心擺動減速裝置12，是在輸入軸14形成有太陽 齒輪（太陽旋轉體）16。太陽齒輪16同時與複數個（在 本例中爲3個）傳動齒輪（偏心體軸驅動體）18嚙合。200900605 IX. Description of the Invention [Technical Field of the Invention] The present invention is an eccentric oscillating reduction device. [Prior Art] An eccentric oscillating reduction device having the following members (for example, refer to Patent Document 1) is well known to the public: a sun rotating body; and an eccentric body shaft driving body by which the sun is a rotating body; and an eccentric body shaft that rotates integrally with the eccentric body shaft driving body; and at least two swinging bodies that are disposed on the axis of the eccentric body shaft Both sides of the direction are oscillated and rotated by the eccentric body shaft; and the internal gears are respectively inscribed in the internal gear. Further, the same applicant has proposed an improved configuration for the configuration of Patent Document 1. The above-described modified eccentric oscillating speed reducing device is shown in Figs. 4 and 5. In the eccentric oscillating reduction gear unit 12, a sun gear (sun rotor) 16 is formed on the input shaft 14. The sun gear 16 is simultaneously meshed with a plurality of (in this example, three) transmission gears (eccentric body shaft drive bodies) 18.
各傳動齒輪18，是分別組裝入所設置的複數支（在本 例中爲3支）偏心體軸20。在各偏心體軸20，偏心體 22A、22B是設置於180°的相位。當輸入軸14旋轉時，將 由前述傳動齒輪18來驅動3支偏心體軸20，而使位於該 3支偏心體軸20之軸方向上相同位置的3個偏心體群22A 200900605 、或22B分別在相同的相位朝同一方向旋轉。2個外齒齒 輪（擺動體）24A、24B，是分別嵌合於該偏心體22A、 22B的外周。因此，該2個外齒齒輪24A、24B，是對應 於各偏心體22A、22B的動作而以180°的相位差形成偏心 旋轉。 偏心體22A、22B與外齒齒輪24A、24B之間的嵌合 ，是隔著滾珠或滾柱（在本例中爲滾柱）26A、26B而轉 動嵌合。外齒齒輪24A、24B是內接嵌合於内齒齒輪28。 内齒齒輪28與殼體30形成一體化，其内齒是由滾柱 狀的銷28P所構成。外齒齒輪24A、24B與内齒齒輪28, 是設定成少數的齒數差（譬如1〜6 )。 在外齒齒輪24A、24B的軸方向兩側，配置有第1、 第2托架（托架體）32、34。2個外齒齒輪2 4A、24B，是 藉由配置於該第1、第2托架32、34與該2個外齒齒輪 24A、24B之間的間隔件25來限制其軸方向的移動。第1 、第2托架32、34是透過螺栓4 0及托架銷42而相互連 結，其整體是隔著圓錐滾柱軸承36、38而可旋轉地由殼 體30所支承。 該構造的偏心擺動減速裝置12，可藉由透過傳動齒輪 18來減速輸入軸14的旋轉後傳達至各偏心體軸20，而使 各偏心體軸20的偏心體22A、22B分別在相同相位旋轉， 進而促使外齒齒輪24A、24B擺動。如此一來，由於產生 外齒齒輪24A、24B與内齒齒輪28間的嚙合位置依序偏移 ，故可伴隨著偏心體軸20的旋轉而在該外齒齒輪24A' 200900605 24B與内齒齒輪28間引發相當於齒數差的相對位移。當 殼體3 0 (内齒齒輪2 8 )被固定時，上述的相對位移可從 一對第1、第2托架32、34側抽出，當第1'第2托架32 、34的自轉受到拘束時，上述相對位移可被當成殼體30 側的旋轉（框架旋轉）而抽出。 〔專利文獻1〕日本特開2004-138094號公報 【發明內容】 〔發明欲解決之課題〕 但是，在上述構造的偏心擺動減速裝置中，譬如是著 眼於軸方向的縮短，但在如同後述實施形態之構造般將傳 動齒輪1 8配置於外齒齒輪24A、24B間的場合中，卻具有 該傳動齒輪18的外周緣與間隔件25的内周緣產生干涉’ 致使傳動齒輪18的尺寸無法增大的問題。因此’當欲在 第一段減速部（太陽齒輪16與傳動齒輪18)中獲得一定 程度以上之減速比時，如同已説明的第4圖、第5圖構造 ，必須使傳動齒輪1 8的配置位置形成於不會與間隔件2 5 產生干涉的位置（圖示例中外齒齒輪24A的軸方向外側） ，而具有導致減速裝置整體的軸方向長度變長的問題。 本發明正是爲了解決上述習知問題而硏發的發明’本 發明的課題爲：不拘泥於間隔件的存在’可藉由將偏心體 軸驅動體配置在與間隔件於軸方向上相同的位置而縮短裝 置整體的軸方向長度’並可藉由合理地消除該間隔件與偏 心體軸驅動體之間的干涉’並無損於間隔件原本的定位功 200900605 能’且可將相當巨大的偏心體軸驅動體在軸方向上配置在 與間隔件相同的位置，而取得第一段減速部的大減速比。 〔解決課題之手段〕 本發明具備：太陽旋轉體；和偏心體軸驅動體，該偏 心體軸驅動體是藉由上述太陽旋轉體而旋轉；和偏心體軸 ，該偏心體軸是與該偏心體軸驅動體一體地旋轉；和至少 2個的擺動體’該至少2個的擺動體是配置於該偏心體軸 之軸方向的兩側，並利用該偏心體軸而擺動旋轉；和內接 齒輪’上述擺動體分別內接於該內接齒輪；及間隔件，該 間隔件是配置於前述擺動體之間，用來限制擺動體之軸方 向的移動’本發明可藉由以下的構造來節決前述的課題： 前述内齒齒輪形成至少在其内周側的軸方向上具有間隙的 形狀，並將前述間隔件配置於該間隙。 本發明是著眼於：在擺動體在軸方向並列複數個，且 在該擺動體與擺動體之間存在間隙的場合中，内齒齒輪只 要存在於對應該擺動體的軸方向部分即可，並不需要包含 各擺動體間的間隙部分而連續地存在。 換言之’在本發明中，内齒齒輪是形成：至少在其内 周側的軸方向上具有間隙的形狀，並將間隔件配置於前述 所形成的間隙內。如此一來，既可將偏心體軸擺動體配置 在軸方向上與間隔件相同的位置（也就是擺動體之間）而 縮短裝置的軸方向長度，又可使該間隔件之裝置半徑方向 的配置位置較傳統更朝外側偏移，而可收容上述的大型偏 -8- 200900605 心體軸驅動體，並可將第一段減速部（亦即’由太陽旋轉 體與偏心體軸驅動體所構成的減速部）的減速比保持成高 減速比。 〔發明的效果〕 根據本發明可獲得：既可使第一段維持高減速比，且 軸方向長度更短的偏心擺動減速裝置。 【實施方式】 〔實施型態〕 以下，根據圖面來詳細地說明本發明之實施形態的其 中一例。 第1圖，是顯示本發明實施形態中偏心擺動減速裝置 之其中一例的剖面圖，第2圖爲沿著第1圖中箭號Π-Π 線的剖面圖。而第1圖是相當於沿著第2圖中箭號I _工 線的剖面圖。 該偏心擺動減速裝置112具備：太陽齒輪（太陽旋轉 體）116，該太陽齒輪（太陽旋轉體）116設於輸入軸114 :和傳動齒輪（偏心體軸驅動體）118 ’該傳動齒輪（偏 心體軸驅動體）118是藉由該太陽齒輪116而旋轉；和偏 心體軸120，該偏心體軸120是與該傳動齒輪118 —體地 旋轉；和外齒齒輪（擺動體）124A、124B，該外齒齒輪（ 擺動體）124 A、I24B是利用該偏心體軸120而擺動旋轉 ;及第1、第2托架（托架體）132'134，該第1、第2 -9- 200900605 托架（托架體）132、134與該外齒齒輪124A、124B的自 轉部分同步。 以下，進行更詳細的說明。 輸入軸114，可與圖面中未顯示之馬達的輸出軸連結 。在輸入軸11 4的前端一體地形成有太陽齒輪116。太陽 齒輪116同時與複數個（在本例中爲2個）傳動齒輪1]8 嚙合。 各傳動齒輪118是分別組裝入複數設置（在本例中爲 2支）的偏心體軸120，2支偏心體軸120可同時且朝同方 向驅動。在各偏心體軸120，以180°的相位設有偏心體 122A、122B，且該偏心體12 2A、122B是分別並列於軸方 向。此外，在各軸之軸方向的相同位置，各軸的偏心體 122A群、及偏心體122B群是分別以相同的相位而組裝成 可朝相同方向旋轉。 外齒齒輪124A是分別嵌合於2個偏心體122A的外 周，而外齒齒輪1 24B則分別嵌合於2個偏心體1 22B的外 周。偏心體122A、122B與外齒齒輪124A、124B之間的 嵌合是隔著滾柱126 A、12 6B而轉動嵌合，如此一來，外 齒齒輪124A、124B，是以180度的相位差而分別內接嚙 合於内齒齒輪128。而外齒齒輪124A、124B在軸方向並 列配置2個（124A、124B )的作法，是爲了確保傳達容量 。各外齒齒輪124A、124B之軸方向的位置，是由斜角滾 珠軸承1 3 6、1 3 8及間隔件1 2 5所限制。 針對内齒齒輪1 2 8與間隔件1 2 5的構造，將於稍後詳 -10- 200900605 述。 在外齒齒輪124A、124B的軸方向兩側，配置著第1 、第2托架132、134。第1、第2托架132、134，是隔著 從螺栓140及第2托架134側形成一體突出的托架銷 134A而互相連結，其整體是隔著前述斜角滾珠軸承136、 138而可旋轉地由殼體130所支承。 前述偏心體軸120，是隔著滾針150、152而由第1、 第2托架132、134所支承。滾針150、152是藉由：分別 將偏心體軸120當作内輪使用，將第1、第2托架132、 134作爲外輪使用，而構成「滾針軸承（needle bearing) 」。但由於滾針150、152無法單獨授受推力方向的反作 用力，因此在該實施形態中，爲了偏心體軸120之軸方向 的定位而採用以下的構造。 亦即，在偏心體軸1 2 0形成有階梯部1 7 0、1 7 2。除此 之外，利用該階梯部170、172，而在該階梯部170、172 與第1 '第2托架1 3 2、1 3 4之間配置有用來限制偏心體軸 120之軸方向移動的墊片174、176。 墊片174、176，是藉由抵接於第1、第2托架132、 134的方式而透過階梯部170、172來執行偏心體軸12〇之 軸方向的定位，並藉由將滾柱】26Α、傳動齒輪118、另一 個滾柱126Β挾持於其間的方式，執行126Α、118、126Β 之軸方向的定位。而墊片174、176是配置成：可對第1、 第2托架132 ' 134 ;及階梯部170、172的其中任一個相 對旋轉。 -11 - 200900605 而圖面中的圖號1 6 7、1 6 9，是用來限制滾針！ 5 〇、 152之軸方向移動的滾針保持具。此外，圖號142是用來 連結第1、第2托架132、134與配合構件（被驅動機械） 的螺桂孔’ 180爲治具安裝部’該治具安裝部是用來安裝 治具（圖示省略），而該治具是在加工偏心體軸120時， 用來停止其旋轉的。 在此，針對内齒齒輪1 2 8及間隔件1 2 5的構造進行說 明。 内齒齒輪128，其本體128Α與殼體130形成一體化 ’並於該本體128Α的内周側具備作爲「内齒」的滾柱狀 銷128Ρ。銷128Ρ是由第1銷128Ρ1及第2銷128Ρ2所構 成。第1、第2銷128Ρ1、128Ρ2是配置成：同軸且在軸 方向上具有間隙128S，而第1銷128Ρ1可與外齒齒輪 12 4Α嚙合，第2銷128Ρ2可與外齒齒輪124Β嚙合。 在該例中，相當於内齒齒輪128之内齒的第1、第2 銷128Ρ1、128Ρ2，是採用2個一組的間歇設置方式（每 設置2個便空出2個空位之意）組裝。就外齒齒輪124A 、1 24B間的嚙合根據上述組裝方式所產生之機構性的動 作而言，可獲得與不具上述「間歇設置」時（譬如，第5 圖所示的例子）完全相同的動作。前述「少量的齒數差」 是指：在不採用上述間歇設置的狀態下之外齒與内齒的齒 數差。 但如同該例所示，在以任何的形式來間歇設置内齒齒 輪128之内齒（第1、第2銷128P1、128P2)的場合中’ -12- 200900605 使第1銷1 2 8 P 1與第2銷1 2 8 P 2在圓周方向的配置相位形 成適當的偏移者較佳。這是由於：隨著外齒齒輪124A、 1 2 4 B之偏心相位形成1 8 0度的偏移，間歇設置的相位形 成偏移者，可藉由動力傳達的脈動或發生於偏心體軸120 的力偶而更進一步的降低。在該實施形態中’是使間歇設 置的相位與外齒齒輪1 24A、1 24B的偏心相位一致’而形 成〗80度的偏移。 間隔件1 2 5整體呈環狀，並配置於間隙1 2 8 S ’該間 隙128S是形成於第1、第2銷128P1、128P2之間’也就 是指内齒齒輪1 2 8之内周側的軸方向上。此外’在該實施 形態中，該間隙1 2 8 S的軸方向寬度W 1 ’是設定成對應於 間隔件1 2 5之軸方向寬度W 2的尺寸’並硏究藉由該間隙 128S的軸方向端面128S1、128S2，來形成間隔件125本 體之軸方向的定位。 接著，說明該偏心擺動減速裝置112的作用。 當輸入軸114旋轉時，透過與該輸入軸114嚙合的傳 動齒輪118同時使2支偏心體軸120減速旋轉。如此一來 ’ 一體安裝於各偏心體軸120的偏心體122A群及122B群 則以相同相位旋轉，而外齒齒輪1 24A、1 24B則是在內接 於内齒齒輪128的狀態下各自擺動旋轉。内齒齒輪128的 本體128A與殼體130形成一體化，由於呈現固定狀態， 因此當偏心體軸120旋轉時是透過偏心體122A、122B而 使外齒齒輪124A、124B擺動旋轉，並使該外齒齒輪124A '124B;與作爲内齒齒輪128之內齒的第1、第2銷 -13- 200900605 128P1、128P2之間的嚙合位置產生依序偏移的現象。 此時，由於外齒齒輪124A、124B的齒數略低於 齒輪1 2 8的齒數（假設在未間歇設置的狀態下），因 藉由該嚙合位置的移動，而對呈固定狀態的内齒齒輪 形成相當於齒數差的相位偏移（自轉）。因此，偏心 120是以相當於該自轉部分的速度而在輸入軸114的 形成公轉，支承著該偏心體軸120的第1、第2托架 、134則是以相當於該公轉速度的速度來旋轉。由於 、第2托架132、134是透過螺栓140及托架銷134A 結，故第1、第2托架132' 134形成一體（形成一個 塊狀體）且緩慢地旋轉，並驅動透過螺栓孔142所連 圖面中未顯示的配合機械（被驅動機械）。 再者，如同該實施形態，當殼體130(内齒齒輪 )被固定時，外齒齒輪12 4A、124B與内齒齒輪128 的相對位移可從第1、第2托架1 3 2、1 3 4側取出，當 第1、第2托架132、134的自轉受到拘束的構造時， 過該第1、第2托架132、134的自轉拘束，將該相對 作爲殼體130側的旋轉（框架旋轉）而取出。 在此，該實施形態的偏心擺動減速裝置1 1 2，於 齒輪124A、124B的兩側具有第1、第2托架132、1 並藉由該第1、第2托架132、134從兩端支承 2支 體軸120，可在支持剛性高且外齒齒輪124A、124B 的狀態下擺動旋轉。 由於2個外齒齒輪124A、124B，是被一對斜角 内齒 此可 128 體軸 周圍 132 第1 而連 大型 結之 128 之間 形成 可透 位移 外齒 34， 偏心 穩疋 滾珠 -14- 200900605 軸承（angular ball bearing) 136、138 所挾持，且間隔件 125配置於內齒齒輪128的間隙128S之間，因此無須特 別設置額外的扣環等定位手段，便可限制軸方向的移動。 具體地說，外齒齒輪1 2 4 A是受到斜角滾珠軸承丨3 6與間 隔件1 2 5限制軸方向的移動，而外齒齒輪1 2 4 B則是分別 由間隔件1 25與斜角滾珠軸承1 3 8限制軸方向的移動。 如第3圖（B )所示，由於間隔件12 5其半徑方向的 最外部125 Μ是配置於内齒齒輪128的間隙（第1、第2 銷128Ρ1、128Ρ2之間），故可使外周側的徑d2設成大於 傳統（請參考第3圖（A))的徑dl(dl<d2)，如此一 來可將内周側的徑D 2設成大於傳統的徑d 1 ( D 1 < D 2 ) 。據此’可兼顧：位於該間隔件1 2 5兩側之外齒齒輪 124A、124B的良好定位；及確保傳動齒輪1 18的充分大 型尺寸。 亦即，可將減速比設成：第一段減速部（太陽齒輪 116及傳動齒輪118)可確保的高減速比，並可沒有阻礙 地將傳動齒輪1 1 8與間隔件1 2 5配置在軸方向的相同位置 ’如此一來，可更進一步縮短軸方向長度。 而在該實施形態中，如以上所述，隨著可確保第一段 減速部（太陽齒輪116與傳動齒輪118)的大減速比，並 藉由將傳動齒輪118配置於2個外齒齒輪124A、124B之 間而獲得「可縮短軸方向的好處」，但在本發明中，就如 何活用上述好處的這一點並無特殊的限制。亦即，該好處 如同文字所描述，除了有助於實現縮短裝置的軸方向之外 -15- 200900605 ’如該實施形態所示，該部分亦可用於治具安裝部1 8 0的 形成’該治具安裝部180是用來安裝加工偏心體軸120時 防止其旋轉的治具（圖不省略）。如此一來，由於能以一 次來夾取偏心體軸120與偏心體122Α、122Β而執行高精 度的加工，而形成可縮短加工時間、降低加工成本及提高 工精度。不僅如此’譬如當軸方向的長度允許與現有者相 同時’上述的好處亦可轉朝增加傳達容量的方向活用。 此外’雖然在上述實施形態中是構成：使第1銷 1 2 8 Ρ 1與第2銷1 2 8 Ρ 2之間隔（間隙1 2 8 S )的寬度W 1對 應於間隔件1 2 5的軸方向寬度W2，並利用該間隙1 2 8 S的 軸方向端面128S1、128S2來執行間隔件125本身的定位 ’但是本發明並非一定要利用來間隙1 2 8 S來執行間隔件 本身的定位’亦可構成：將間隙128S設置的較大，間隔 件125只需負責「使外齒齒輪124Α、124Β的間隔不會縮 小至特定値以下」作用’而可在該間隙1 2 8 S中略朝軸方 向移動。 〔産業上的利用性〕 本發明可在傳統上導入該種偏心擺動減速裝置的領域 中’作爲既可實現高減速比’又可更進一步縮短軸方向長 度的改良品使用。 【圖式簡單說明】 第1圖：爲顯示本發明實施形態之其中一例的偏心擺 -16 - 200900605 動減速裝置的縱剖面圖。 第2圖：爲沿著上述減速裝置之箭號II - II線的剖面 圖。 第3圖：是顯示間隔件之配置位置與習知例進行比較 的示意圖。 第4圖：爲顯示習知偏心擺動減速裝置之其中一例的 剖面圖。 第5圖：爲沿著第4圖之箭號V — V線的剖面圖。 【主要元件符號說明】 I 1 2 :偏心擺動減速裝置 II 4 :輸入軸 116:太陽齒輪（太陽旋轉體） 1 1 8 :傳動齒輪（偏心體軸驅動體） 1 2 0 :偏心體軸 1 22A、1 22B :偏心體 124A、124B :外齒齒輪（擺動體） 1 2 5 :間隔件 1 2 8 :内齒齒輪 128P1、128P2:第 1、第 2 銷（内齒） 1 2 8 S :間隙 1 2 8 S 1、1 2 8 S 2 :間隙的軸向端面 130 :殼體 132:第1托架（托架體） -17 - 200900605 134:第2托架（托架體） 136、138:斜角滾珠軸承（angular ball bearing 1 4 0 :螺栓 142 :螺栓孔Each of the transmission gears 18 is assembled into a plurality of (in this example, three) eccentric body shafts 20, respectively. In each of the eccentric body shafts 20, the eccentric bodies 22A and 22B are disposed at a phase of 180°. When the input shaft 14 rotates, the three eccentric body shafts 20 are driven by the aforementioned transmission gear 18, and the three eccentric body groups 22A 200900605 or 22B located at the same position in the axial direction of the three eccentric body shafts 20 are respectively The same phase rotates in the same direction. Two externally toothed gears (swinging bodies) 24A and 24B are fitted to the outer circumferences of the eccentric bodies 22A and 22B, respectively. Therefore, the two externally toothed gears 24A and 24B are eccentrically rotated by a phase difference of 180° in accordance with the operation of each of the eccentric bodies 22A and 22B. The fitting between the eccentric bodies 22A and 22B and the externally toothed gears 24A and 24B is rotationally fitted via balls or rollers (rollers in this example) 26A and 26B. The externally toothed gears 24A, 24B are internally fitted to the internally toothed gear 28. The internal gear 28 is integrated with the housing 30, and the internal teeth are formed by a roller-shaped pin 28P. The externally toothed gears 24A, 24B and the internally toothed gear 28 are set to a small number of teeth (for example, 1 to 6). The first and second brackets (bracket bodies) 32 and 34 are disposed on both sides of the externally toothed gears 24A and 24B in the axial direction. The two externally toothed gears 2 4A and 24B are disposed in the first and the second The spacers 25 between the brackets 32, 34 and the two externally toothed gears 24A, 24B restrict movement in the axial direction. The first and second brackets 32 and 34 are connected to each other via the bolts 40 and the bracket pins 42, and are entirely rotatably supported by the casing 30 via the tapered roller bearings 36 and 38. The eccentric oscillating reduction gear 12 of this structure can be transmitted to the eccentric body shafts 20 by transmitting the rotation of the input shaft 14 through the transmission gear 18, and the eccentric bodies 22A and 22B of the eccentric body shafts 20 are respectively rotated in the same phase. Further, the external gears 24A, 24B are caused to swing. As a result, since the meshing positions between the externally toothed gears 24A, 24B and the internal gear 28 are sequentially shifted, the external gears 24A' 200900605 24B and the internally toothed gears can be accompanied by the rotation of the eccentric body shaft 20. The 28 pairs caused a relative displacement equivalent to the difference in the number of teeth. When the housing 30 (the internal gear 28) is fixed, the above relative displacement can be extracted from the pair of first and second brackets 32, 34, and the rotation of the first 'second bracket 32, 34 When restrained, the relative displacement described above can be extracted as the rotation of the casing 30 side (frame rotation). [Problem to be Solved by the Invention] However, in the eccentric oscillating reduction gear of the above-described structure, for example, attention is paid to shortening in the axial direction, but it is implemented as will be described later. In the case where the transmission gear 18 is disposed between the externally toothed gears 24A, 24B, the outer peripheral edge of the transmission gear 18 interferes with the inner circumference of the spacer 25, so that the size of the transmission gear 18 cannot be increased. The problem. Therefore, when a certain degree of reduction ratio is to be obtained in the first stage reduction unit (the sun gear 16 and the transmission gear 18), the configuration of the transmission gear 18 must be configured as in the fourth and fifth configurations explained. The position is formed at a position that does not interfere with the spacer 25 (the outer side in the axial direction of the externally toothed gear 24A in the illustrated example), and has a problem that the axial length of the entire reduction gear unit becomes long. The present invention has been made to solve the above-mentioned conventional problems. The subject of the present invention is that the eccentric body shaft driving body can be disposed in the same direction as the spacer in the axial direction, without being limited to the existence of the spacer. Positioning shortens the axial length of the device as a whole and can reasonably eliminate the interference between the spacer and the eccentric body drive body 'without the original positioning work of the spacer 200900605' and can be quite large eccentricity The body shaft driving body is disposed at the same position as the spacer in the axial direction to obtain a large reduction ratio of the first stage speed reducing portion. [Means for Solving the Problem] The present invention includes: a solar rotating body; and an eccentric body shaft driving body that is rotated by the sun rotating body; and an eccentric body axis, the eccentric body axis is eccentric The body shaft driving body rotates integrally; and at least two swinging bodies 'the at least two rocking bodies are disposed on both sides of the axis direction of the eccentric body shaft, and are oscillated and rotated by the eccentric body shaft; and inscribed The gears 'the above-mentioned oscillating bodies are respectively connected to the internal gears; and the spacers are disposed between the oscillating bodies for restricting the movement of the oscillating body in the axial direction. The present invention can be configured by the following structure In the above-described problem, the internal gear is formed in a shape having a gap at least in the axial direction on the inner circumferential side thereof, and the spacer is disposed in the gap. According to the present invention, in the case where the swinging body is juxtaposed in the axial direction, and the gap exists between the swinging body and the rocking body, the internal gear may be present in the axial direction portion corresponding to the rocking body, and It does not need to include a gap portion between the respective oscillating bodies to continuously exist. In other words, in the present invention, the internally toothed gear is formed in a shape having a gap at least in the axial direction of the inner peripheral side thereof, and the spacer is disposed in the gap formed as described above. In this way, the eccentric body shaft oscillating body can be disposed in the axial direction at the same position as the spacer (that is, between the oscillating bodies) to shorten the axial length of the device, and the spacer can be arranged in the radial direction of the device. The configuration position is shifted to the outside more than the conventional one, and can accommodate the above-mentioned large partial -8-200900605 cardiac body drive body, and the first speed reduction portion (that is, 'the sun rotation body and the eccentric body shaft drive body The reduction ratio of the configured deceleration portion is maintained at a high reduction ratio. [Effects of the Invention] According to the present invention, it is possible to obtain an eccentric oscillating speed reducing device which can maintain a high reduction ratio in the first stage and a shorter length in the axial direction. [Embodiment] [Embodiment] Hereinafter, an example of an embodiment of the present invention will be described in detail based on the drawings. Fig. 1 is a cross-sectional view showing an example of an eccentric oscillating speed reducing device according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along line Π-Π in Fig. 1 . The first figure is a cross-sectional view corresponding to the arrow I _ line in Fig. 2 . The eccentric oscillating reduction gear unit 112 includes a sun gear (solar rotating body) 116 provided on the input shaft 114: and a transmission gear (eccentric body shaft driving body) 118' the transmission gear (eccentric body) The shaft drive body 118 is rotated by the sun gear 116; and the eccentric body shaft 120 is integrally rotated with the transmission gear 118; and the external gear (swing body) 124A, 124B, The externally toothed gears (rocking bodies) 124 A and I24B are oscillated and rotated by the eccentric body shaft 120; and the first and second brackets (frame body) 132 134, the first and second -9-200900605 The brackets (frame bodies) 132, 134 are synchronized with the self-rotating portions of the external gears 124A, 124B. Hereinafter, a more detailed description will be given. The input shaft 114 is coupled to an output shaft of a motor not shown in the drawing. A sun gear 116 is integrally formed at the front end of the input shaft 114. The sun gear 116 is simultaneously meshed with a plurality of (in this example, two) transmission gears 1]8. Each of the transmission gears 118 is an eccentric body shaft 120 that is respectively incorporated in a plurality of sets (two in this example), and the two eccentric body shafts 120 can be driven simultaneously and in the same direction. The eccentric body shafts 120 are provided with eccentric bodies 122A and 122B at a phase of 180°, and the eccentric bodies 12 2A and 122B are respectively arranged in the axial direction. Further, at the same position in the axial direction of each axis, the eccentric body 122A group and the eccentric body 122B group of each axis are assembled in the same phase so as to be rotatable in the same direction. The externally toothed gears 124A are fitted to the outer circumferences of the two eccentric bodies 122A, respectively, and the externally toothed gears 1 24B are fitted to the outer circumferences of the two eccentric bodies 1 22B, respectively. The fitting between the eccentric bodies 122A and 122B and the externally toothed gears 124A and 124B is rotationally fitted via the rollers 126 A and 12 6B. Thus, the externally toothed gears 124A and 124B are 180 degrees out of phase. The inner teeth are respectively meshed with the internal gears 128. On the other hand, the external gears 124A and 124B are arranged in parallel in the axial direction (124A, 124B) in order to secure the transmission capacity. The position of the externally toothed gears 124A, 124B in the axial direction is limited by the bevel ball bearings 1 36, 1 3 8 and the spacers 1 2 5 . The configuration for the internally toothed gear 1 28 and the spacer 1 2 5 will be described later in detail -10-200900605. The first and second brackets 132 and 134 are disposed on both sides of the external gears 124A and 124B in the axial direction. The first and second brackets 132 and 134 are coupled to each other via a bracket pin 134A that integrally protrudes from the bolt 140 and the second bracket 134 side, and the entire brackets 136 and 138 are interposed therebetween. It is rotatably supported by the housing 130. The eccentric body shaft 120 is supported by the first and second brackets 132 and 134 via the needle rollers 150 and 152. The needle rollers 150 and 152 are formed by using the eccentric body shaft 120 as an inner wheel and the first and second brackets 132 and 134 as outer wheels, respectively, to constitute a "needle bearing". However, since the needle rollers 150 and 152 cannot individually impart the reaction force in the thrust direction, in the embodiment, the following structure is employed for the positioning of the eccentric body shaft 120 in the axial direction. That is, the step portions 1 7 0 and 1 7 2 are formed on the eccentric body axis 1 20 . In addition, the step portions 170 and 172 are used to restrict the axial movement of the eccentric body shaft 120 between the step portions 170 and 172 and the first 'second brackets 1 3 2 and 1 34. Shims 174, 176. The spacers 174 and 176 are configured to pass through the step portions 170 and 172 to abut the axial direction of the eccentric body shaft 12 by abutting against the first and second brackets 132 and 134, and by positioning the roller The 26 Α, the transmission gear 118, and the other roller 126 are held therebetween, and the positioning in the axial direction of 126 Α, 118, 126 执行 is performed. The spacers 174, 176 are arranged to be rotatable relative to each of the first and second brackets 132' 134; and the step portions 170, 172. -11 - 200900605 The figure numbers 1 6 7 and 1 6 9 in the drawing are used to limit the needle roller! 5 The needle holder that moves in the direction of the axis of 152 and 152. Further, reference numeral 142 is a jig hole '180 for connecting the first and second brackets 132 and 134 and the mating member (driven machine) to the jig attachment portion. The jig attachment portion is for mounting the jig. (not shown), and the jig is used to stop the rotation of the eccentric body shaft 120. Here, the configuration of the internally toothed gear 1 28 and the spacer 1 25 will be described. The internal gear 128 has a main body 128A integrated with the casing 130, and has a roller-shaped pin 128A as an "internal tooth" on the inner peripheral side of the main body 128A. The pin 128 is composed of the first pin 128Ρ1 and the second pin 128Ρ2. The first and second pins 128A1, 1282 are arranged coaxially and have a gap 128S in the axial direction, and the first pin 128Ρ1 is engageable with the external gear 12 4Α, and the second pin 128Ρ2 is engageable with the external gear 124Β. In this example, the first and second pins 128Ρ1 and 128Ρ2 corresponding to the internal teeth of the internal gear 128 are assembled by a two-group intermittent setting method (two vacancies are provided for each of two). . The meshing between the externally toothed gears 124A and 1 24B can be performed in the same manner as the above-described "intermittent setting" (for example, the example shown in Fig. 5). . The "small amount of difference in the number of teeth" refers to the difference in the number of teeth between the external teeth and the internal teeth in the state where the intermittent setting is not employed. However, as shown in this example, in the case where the internal teeth (the first and second pins 128P1, 128P2) of the internal gear 128 are intermittently provided in any form, '-12-200900605 makes the first pin 1 2 8 P 1 It is preferable to form an appropriate offset with the arrangement phase of the second pin 1 2 8 P 2 in the circumferential direction. This is because, as the eccentric phase of the externally toothed gears 124A, 1 2 4 B is shifted by 180 degrees, the intermittently set phase forms an offset, which can be caused by the pulsation of the power transmission or occurs on the eccentric body shaft 120. The force is even further reduced. In this embodiment, 'the phase is set to coincide with the eccentric phase of the externally toothed gears 1 24A, 1 24B' to form an offset of 80 degrees. The spacer 1 2 5 is annular in shape and disposed in the gap 1 2 8 S '. The gap 128S is formed between the first and second pins 128P1 and 128P2, that is, the inner circumference side of the internal gear 1 2 8 In the direction of the axis. Further, in this embodiment, the axial width W 1 ' of the gap 1 2 8 S is set to a size ' corresponding to the axial width W 2 of the spacer 1 25 and the axis by the gap 128S is considered. The direction end faces 128S1, 128S2 are formed to form the positioning of the body of the spacer 125 in the axial direction. Next, the action of the eccentric oscillating speed reducing device 112 will be described. When the input shaft 114 rotates, the two eccentric body shafts 120 are simultaneously decelerated and rotated by the transmission gear 118 engaged with the input shaft 114. As a result, the eccentric body 122A group and the 122B group integrally attached to the eccentric body shafts 120 are rotated in the same phase, and the externally toothed gears 1 24A and 1 24B are respectively oscillated in the state of being connected to the internal gears 128. Rotate. The body 128A of the internal gear 128 is integrated with the housing 130, and since it is in a fixed state, when the eccentric body shaft 120 rotates, the external gears 124A, 124B are oscillated and rotated by the eccentric bodies 122A, 122B, and the outer teeth are rotated. The meshing position between the tooth gears 124A'124B and the first and second pins-13-200900605 128P1, 128P2 which are internal teeth of the internal gear 128 is sequentially shifted. At this time, since the number of teeth of the external gears 124A, 124B is slightly lower than the number of teeth of the gear 1 2 8 (assuming that the state is not intermittently set), the internal gear is fixed by the movement of the meshing position. A phase shift (rotation) corresponding to the difference in the number of teeth is formed. Therefore, the eccentric 120 revolves on the input shaft 114 at a speed corresponding to the rotation portion, and the first and second brackets 134 that support the eccentric body shaft 120 are at a speed corresponding to the revolution speed. Rotate. Since the second brackets 132 and 134 are coupled to the bracket 140 and the bracket pin 134A, the first and second brackets 132' 134 are integrally formed (formed as a block) and slowly rotated to drive through the bolt holes. 142 is the matching machine (driven machine) not shown in the drawing. Furthermore, as in this embodiment, when the housing 130 (internal gear) is fixed, the relative displacement of the externally toothed gears 12 4A, 124B and the internal gear 128 can be from the first and second brackets 1 2 2, 1 When the rotation of the first and second brackets 132 and 134 is restrained, the first and second brackets 132 and 134 are restrained by the rotation of the first and second brackets 132 and 134, and the relative rotation is the side of the casing 130. (frame rotation) and taken out. Here, the eccentric rocking reduction gear 1 1 2 of the embodiment has the first and second brackets 132 and 1 on both sides of the gears 124A and 124B, and the first and second brackets 132 and 134 are The end support 2 support shafts 120 are swingably rotatable in a state in which the rigidity is high and the externally toothed gears 124A, 124B are supported. Since the two externally toothed gears 124A, 124B are formed by a pair of beveled internal teeth, the outer circumference of the 128 body axis 132 is formed by the first and the large joint 128 is formed, and the eccentrically stable ball 14- 200900605 The bearings are held by the angular ball bearings 136 and 138, and the spacers 125 are disposed between the gaps 128S of the internal gears 128. Therefore, it is possible to limit the movement in the axial direction without additionally providing an additional snap ring or the like. Specifically, the external gear 1 2 4 A is subjected to the movement of the oblique ball bearing 丨36 and the spacer 1 2 5 in the axial direction, and the external gear 1 2 4 B is respectively separated by the spacer 1 25 and The angular ball bearing 1 3 8 limits the movement in the axial direction. As shown in Fig. 3(B), since the outermost 125 半径 in the radial direction of the spacer 125 is a gap (between the first and second pins 128Ρ1 and 128Ρ2) disposed in the internal gear 128, the outer circumference can be made. The diameter d2 of the side is set larger than the diameter dl (dl < d2) of the conventional (refer to FIG. 3 (A)), so that the diameter D 2 of the inner circumference side can be set larger than the conventional diameter d 1 (D 1 < D 2 ). Accordingly, it is possible to achieve both good positioning of the toothed gears 124A, 124B on both sides of the spacer 1 2 5; and ensuring a sufficiently large size of the transmission gear 1 18 . That is, the reduction ratio can be set such that the first stage of the speed reduction portion (the sun gear 116 and the transmission gear 118) can ensure a high reduction ratio, and the transmission gear 1 18 and the spacer 1 2 5 can be disposed without hindrance. The same position in the axial direction 'as a result, the length in the axial direction can be further shortened. In this embodiment, as described above, the large reduction ratio of the first stage speed reduction portion (the sun gear 116 and the transmission gear 118) can be ensured, and the transmission gear 118 is disposed on the two external gears 124A. In the present invention, there is no particular limitation on how to utilize the above advantages. That is, the benefit is as described in the text, except that it contributes to shortening the axial direction of the device -15-200900605 'as shown in this embodiment, this portion can also be used for the formation of the fixture mounting portion 180" The jig attachment portion 180 is a jig (not shown) for preventing the rotation of the eccentric body shaft 120 when it is processed. In this way, since the eccentric body shaft 120 and the eccentric bodies 122 Α and 122 夹 can be gripped at a time to perform high-precision machining, the formation time can be shortened, the processing cost can be reduced, and the work accuracy can be improved. Not only that, for example, the length in the axial direction is allowed to be the same as the existing one. The above-mentioned benefits can also be used in the direction of increasing the transmission capacity. Further, in the above embodiment, the width W 1 of the interval (gap 1 2 8 S ) between the first pin 1 2 8 Ρ 1 and the second pin 1 2 8 Ρ 2 corresponds to the spacer 1 25 . The axial direction width W2, and the positioning of the spacer 125 itself is performed using the axial end faces 128S1, 128S2 of the gap 1 2 8 S 'but the present invention does not necessarily utilize the gap 1 2 8 S to perform the positioning of the spacer itself' Alternatively, the gap 128S may be set to be large, and the spacer 125 only needs to be responsible for "making the spacing of the externally toothed gears 124 Α, 124 不会 not to be reduced below a certain 」" and may be slightly oriented in the gap 1 2 8 S Move in direction. [Industrial Applicability] The present invention can be used as an improved product which can be introduced into the field of such an eccentric oscillating reduction device as a high reduction ratio and a further shortening of the axial length. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal sectional view showing an eccentric pendulum-16 - 200900605 dynamic speed reduction device which is an example of an embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line II-II of the above-described reduction gear unit. Fig. 3 is a schematic view showing the arrangement position of the spacers in comparison with a conventional example. Fig. 4 is a cross-sectional view showing an example of a conventional eccentric oscillating speed reducing device. Fig. 5 is a cross-sectional view taken along the line V-V of the arrow of Fig. 4. [Description of main component symbols] I 1 2 : Eccentric oscillating reduction gear II 4 : Input shaft 116: Sun gear (solar rotating body) 1 1 8 : Transmission gear (eccentric body shaft drive) 1 2 0 : Eccentric shaft 1 22A , 1 22B : eccentric body 124A, 124B : external gear (swing body) 1 2 5 : spacer 1 2 8 : internal gear 128P1, 128P2: first and second pin (internal tooth) 1 2 8 S : clearance 1 2 8 S 1 , 1 2 8 S 2 : axial end face 130 of the gap: housing 132: first bracket (bracket body) -17 - 200900605 134: second bracket (bracket body) 136, 138 : Angled ball bearing (angular ball bearing 1 4 0 : bolt 142 : bolt hole