1272353 (1) 九、發明說明 【發明所屬的技術領域】 本發明是關於，與固定在輸入軸的固定皮帶輪半體一 起構成驅動皮帶輪的可動皮帶輪半體’是繞掛著用來將動 力傳達到輸出軸所安裝的從動皮帶輪側的循環式的V型皮 帶，爲了要使其與上述固定皮帶輪半體之間所形成的皮帶 溝槽的寬度變化，是以可朝軸方向相對移動而不能相對旋 • 轉地被結合在上述輸入軸；而在上述可動皮帶輪半體，是 以不能朝軸方向相對移動且可繞著軸線相對旋轉的方式， 連結著可朝上述輸入軸的軸線方向滑動的滑動齒輪的其中 一端部，是以讓軸方向位置及軸線周圍的位置成爲一定的 方式，在與上述輸入軸同軸配置的圓筒狀的螺紋軸的外周 ’螺合著上述滑動齒輪的內周之V型皮帶式無段變速機。 【先前技術】 ® 這種V型皮帶式無段變速機，例如在專利文獻丨所習 知的構造。 [專利文獻1 ] 曰本專利第29673 74號公報 【發明內容】 [發明欲解決的課題] 在迨種V型皮帶式無段變速機’必須避免灰塵侵入到 滑動齒輪的滑動支承部、或滑動齒輪及螺紋軸的螺合部而1272353 (1) EMBODIMENT OF THE INVENTION [Technical Field] The present invention relates to a movable pulley half body constituting a drive pulley together with a fixed pulley half fixed to an input shaft, which is used to transmit power to The circulating V-belt on the driven pulley side to which the output shaft is mounted, in order to change the width of the belt groove formed between the fixed pulley and the fixed pulley half, is relatively movable in the axial direction and cannot be opposite The rotating/rotating ground is coupled to the input shaft; and the movable pulley half is coupled to slide in the axial direction of the input shaft so as not to be relatively movable in the axial direction and relatively rotatable about the axis. One end portion of the gear is such that the position in the axial direction and the position around the axis are constant, and the outer circumference of the cylindrical screw shaft coaxially disposed with the input shaft is screwed to the inner circumference of the sliding gear. Belt type stepless speed changer. [Prior Art] This V-belt type stepless speed changer is, for example, a structure known in the patent document. [Patent Document 1] Japanese Patent Publication No. 29673749 [Disclosed] [Problem to be Solved by the Invention] In the V-belt type stepless transmission, it is necessary to prevent dust from intruding into the sliding support portion of the sliding gear or sliding. Gear and threaded shaft
1272353 1 · . (2) 造成作動不順暢的情形，在上述專利文獻1所揭示的構造 中’是以較大的外殼，來覆蓋滑動齒輪全體、及滑動齒輪 與螺紋軸的螺合部。於是，當將這種較大的外殼收容於變 速機殻體內時，會導致讓變速機殻體大型化。 使用密封構件，是可防止灰塵侵入到滑動齒輪的滑動 支承部的情形，而如果以較小的外殼來覆蓋滑動齒輪及轂 部的螺合部，在外殼的內周及滑動齒輪的外周間中介安裝 φ 環狀的密封構件的話，則可避免讓變速機殻體大型化。而 爲了使變速段從TOP朝向LOW側急速變化，當使驅動皮 帶輪的可動皮帶輪半體朝向增大皮帶溝槽的寬度的側邊急 速移動時，面對著可動皮帶輪相反側的滑動齒輪的端部而 形成於外殻內的環狀室的容積會急劇收縮，藉由讓環狀室 內急劇增壓，而有可能使外殼的內周及滑動齒輪的外周間 的密封構件的密封機能受損。 本發明，鑒於這種情形，其目的要提供一種V型皮帶 • 式無段變速機，藉由使用較小的外殻，來避免變速機殻體 大型化，且不會由於急劇的增壓，導致外殼的內周及滑動 齒輪的外周間的密封構件的密封機能受損。 [用以解決課題的手段] 爲了達成上述目的，第1發明，是與固定在輸入軸的 固定皮帶輪半體一起構成驅動皮帶輪的可動皮帶輪半體’ 是繞掛著用來將動力傳達到輸出軸所安裝的從動皮帶輪側 的循環式的V型皮帶，且爲了要使其與上述固定皮帶輪半 -6- (3) (3)1272353 體之間所形成的皮帶溝槽的寬度變化，是可朝軸方向相對 移動而不能相對旋轉地被結合在上述輸入軸；而在上述可 動皮帶輪半體’是以不能朝軸方向相對移動且可繞著軸線 相對旋轉的方式’連結著可朝上述輸入軸的軸線方向滑動 的滑動齒輪的其中一端部，是以讓軸方向位置及軸線周圍 的位置成爲一定的方式，在與上述輸入軸同軸配置的圓筒 狀的螺紋軸的外周，螺合著上述滑動齒輪的內周之V型皮 帶式無段變速機，其特徵爲：在：具有固定於上述螺紋軸 的端壁部，形成爲有底圓筒狀，並且將上述滑動齒輪及上 述螺紋軸的螺合部予以覆蓋的外殼的內周、以及上述滑動 齒輪的外周之間，是中介安裝著環狀的密封構件，使面對 著上述滑動齒輪的另一端部，並且將上述外殼內所形成的 環狀室連通到外部的連通孔，設置在上述螺紋軸或上述外 殻。 第2發明，是針對第1發明，將相對於上述輸入軸的 軸方向位置設爲一定且同軸地圍繞該輸入軸的上述螺紋軸 ’相對於上述軸線周圍的旋轉方向，是被進行定位，讓防 震構件中介在其與變速機殼體之間。 [發明效果] 是以外殻來覆蓋滑動齒輪及螺紋軸的螺合部，藉由將 環狀的密封構件中介安裝在外殼的內周及滑動齒輪的外周 之間，藉由使用較小的外殼，則可防止由於灰塵的侵入而 造成作動不順暢的情形，可避免讓變速機殼體大型化。並 1272353 κ (4) 且由於外殻內的環狀室是經由連通孔連通到外部，所以可 避免環狀室急劇增壓的情形，且不會由於急劇的增壓，導 致外殻的內周及滑動齒輪的外周間的密封構件的密封機能 受損。 藉由第2發明，從滑動齒輪所受到的負荷之中，沿著 螺紋軸的軸方向的負荷不會作用於防震構件，而只有螺紋 軸的旋轉方向的負荷會作用於防震構件，所以可延長防震 Β 構件的使用壽命，能夠使螺紋軸的防震支承構造小型化。 【實施方式】 以下，是根據附圖所不的本發明的一實施例，來說明 本發明的實施方式。 第1圖〜第9圖是顯示本發明的一實施例，第1圖是 動力單元及後輪的側面圖，第2圖是第1圖的2 — 2線剖 面圖，第3圖是以LOW狀態來顯示第2圖的驅動皮帶輪 ί 附近的放大圖，第4圖是從可動皮帶輪側來觀察螺栓軸及 支承板的側面圖，第5圖是TOP狀態的對應於第3圖的剖 面圖，第6圖是將齒輪減速機構的一部分放大顯示的剖面 圖，第7圖是第6圖的7 — 7線剖面圖，第8圖是從與第7 圖同一方向來觀察外殼構件的視圖，第9圖是從與第8圖 相反側來觀察外殼構件的視圖。 首先在第1圖及第2圖，以：配置在驅動輪也就是後 輪WR的前方的引擎E、以及在該引擎E及上述後輪WR 之間所設置的V型皮帶式無段變速機Μ所構成的動力單 -8- (5) 1272353 元P，是被搭載於速克達型機車的車體框架（沒有圖不） ，配置於動力單元P的後部右側的後輪WR，是被軸支承 在動力單元P的後部。 引擎E的引擎主體1 1，是具備有：將具有與後輪WR 的旋轉軸線平行的旋轉軸線的曲軸1 6可自由旋轉地支承 著的曲軸箱1 2、結合於曲軸箱1 2的氣缸體.1 3、在曲軸箱 1 2的相反側而結合於氣缸體1 3的氣缸頭1 4、以及在氣缸 體1 3的相反側而結合於氣缸頭1 4的氣缸頭外殻1 5。 氣缸體1 3，是配置成：讓設置於該氣缸體1 3的氣缸 內缸1 7的軸線沿著機車的前後方向稍微朝前上方而成爲 略水平的。曲軸箱1 2，是由：在包含上述氣缸軸線並且與 曲軸1 6的軸線垂直枏交的平面所結合的一對箱體半體1 2a 、：l2b所構成，在兩箱體半體12a、12b之中的其中一方的 箱體半體1 2a及曲軸1 6之間，是中介安裝著滾珠軸承1 8 ，在另一方的箱體半體12b及曲軸16之間，是中介安裝 著：滾子軸承1 9、及配置在較該滾子軸承1 9更外側處的 環狀的密封構件2 0。 在上述氣缸內缸1 7，是可自由滑動地嵌合著活塞2 1 ，曲軸1 6，是經由曲軸銷栓3 7及連桿3 8而連結於活塞 2 1。在氣缸頭1 4及上述活塞2 1之間形成有燃燒室2 3，用 來控制對於該燃燒室23的進氣情形的進氣閥24、及用來 控制來自於上述燃燒室23的排氣情形的排氣閥2 5，是以 ••在朝向與曲軸1 6的旋轉軸線垂直相交的平面的投影圖 上，是排列成略V字型的方式，被配設在氣缸頭1 4。並 -9- (6) 1272353 且面對於燃燒室2 3的火星塞2 6，是在朝向機車的行進方 向前方的狀態，被安裝在氣缸頭1 4的左側側面。 在氣缸頭1 4及氣缸頭外殻1 5之間，是收容著··將上 述進氣閥24及排氣閥25進行開閉驅動的閥門機構30，該 閥門機構3 0，是具有與曲軸1 6的軸線平行的軸線，而可 自由旋轉地被支承於氣缸頭14，並且包含有：具有進氣用 及排氣用凸輪28、29的凸輪軸27。 ® 在凸輪軸27的其中一端部是固定著從動鏈輪3 1。另 一方面，在曲軸1 6，在較滾珠軸承1 8更外側處，在對應 於上述從動鏈輪31的位置，是固定著第一驅動鏈輪32， 在第一驅動鏈輪3 2及從動鏈輪3 1，繞掛著循環式的凸輪 鏈條33，凸輪鏈條33，是可運行地被收容於：涵蓋於氣 缸體1 3、氣缸頭1 4、及氣缸頭外殼1 5所形成的鏈條室3 4 內。藉由該第一驅動鏈輪3 2、從動鏈輪3 1、及凸輪鏈條 3 3，是以曲軸1 6的轉數的1 /2的轉數，來旋轉驅動凸輪 •軸 27。 在較第一驅動鏈輪3 2更外側，在曲軸1 6固定著第二 驅動鏈輪4 0。另一方面，從曲軸箱1 2內的下部將油汲起 的油泵浦4 1 (參照第1圖）、以及在氣缸體1 3及氣缸頭 1 4所設置的冷卻水套43使冷卻水進行循環的冷卻水泵浦 42 (參照第1圖），是同軸相連，而被設置在曲軸箱12 的下部，將旋轉動力從第二驅動鏈輪40，經由鏈條（沒有 圖示），傳達到上述油泵浦41及上述冷卻冰泵浦42。 在較第二驅動鏈輪40更外側處，是配置有發電機46 -10- (7) 1272353 ，該發電機46，是具備有··被固定在曲軸箱1 2的右側 所安裝的右外殼45的定子47、以及以圍繞該定子47的 式，被固定在曲軸1 6的外轉子48。 在第二驅動鏈輪4 0及上述外轉子4 8之間，是配置 :同軸地圍繞曲軸1 6，在該曲軸1 6可相對旋轉地被支 著的從動齒輪49，該從動齒輪49，是經由單向離合器 被連結在上述外轉子4 8。在上述從動齒輪4 9，可輸入 自於沒有圖示的起動機馬達的旋轉動力，當引擎E起動 ’來自於起動機馬達的驅動力會被傳達到曲軸1 6，在引 E起動之後，藉由單向離合器5 0的作動，讓來自於曲 1 6的動力不會被傳達到起動機馬達側。 V型皮帶式無段變速機Μ，是被收容在變速機箱體 內的收容室5 6，該變速機箱體5 1，是從側邊覆蓋引擎 體1 1的一部分，被連設於引擎主體1 1，並且延伸設置 後輪WR的左側·，變速機箱體5丨，是由：與構成曲軸 12的一對箱體半體12a、12b之中的箱體半體12b —體 相連的內側箱體52、從外側覆蓋該內側箱體52的外側 體53、在外側箱體S3內被鎖裝於內側箱體52的後部的 板54、以及被夾在內側箱體52及外側箱體53的前部之 的減速齒輪箱體5 5所構成；在內側箱體5 2及蓋板5 4 間，是形成了與收容室5 6隔絕的齒輪室5 7。 V型皮帶式無段變速機M，是以：在從曲軸箱i 2 入到收容室5 6內的作爲輸入軸的曲軸1 6的另〜端部所 裝的驅動皮帶輪5 8、具有與曲軸】6平行的軸線，在內 面 方 有 承 50 來 時 擎 軸 5 1 主 到 箱 地 箱 蓋 間 之 突 安 側 -11 - (8) (8)1272353 箱體5 2及蓋板5 4可自由旋轉地被支承著的輸出軸6 1所 安裝的從動皮帶輪5 9、以及從驅動皮帶輪5 8將動力傳達 到從動皮帶輪5 9的循環式的V型皮帶60所構成。 驅動皮帶輪5 8，是具備有：被固定在曲軸1 6的固定 皮帶輪半體62、以及可相對於固定皮帶輪半體62接近、 分離的可動皮帶輪半體63，以讓V型皮帶繞掛的方式， 爲了要使固定皮帶輪半體62及可動皮帶輪半體63之間所 形成的皮帶溝槽64的寬度變化，而使上述可動皮帶輪半 體63朝軸方向驅動的動力，會從被安裝在變速機箱體5 1 的電動馬達6 5，經由齒輪減速機構6 6，被傳達到上述可 動皮帶輪半體6 3。 而從動皮帶輪59，則是具備有：可相對旋轉地將輸出 軸6 1圍繞成同軸狀的內筒部70、以可繞著軸線相對轉動 且可在軸線方向相對移動的方式，可滑動地嵌合內筒部70 的外筒部71、固定於內筒部70的固定皮帶輪半體72、與 該固定皮帶輪半體72相對向而被固定在外筒部71的可動 皮帶輪半體73、因應於該可動皮帶輪半體73及固定皮帶 輪半體72之間的相對旋轉相位差，而使軸方向的分力作 用於兩皮帶輪半體72、73之間，而被設置在內筒部70及 外筒部7 1之間的扭力凸輪機構74、在將可動皮帶輪半體 73夾在其與固定皮帶輪半體72之間的位置，被固定在內 筒部70的彈簧座構件75、圍繞外筒部7 1而被壓縮設置在 可動皮帶輪半體73及彈簧座構件75之間的線圈彈簧76、 以及伴隨著引擎轉數超過設定轉數的情形而成爲動力傳達 -12- (9) 1272353 狀態，而被設置在內筒部70及輸出軸6 1之間的離心離 器77 ;在驅動皮帶輪58的固定皮帶輪半體72及可動皮 輪半體73之間所形成的皮帶溝槽78，是繞掛著V型皮 60 ° 而從動皮帶輪5 9的固定皮帶輪半體7 2及可動皮帶 半體7 2之間的間隔，是藉由：利用上述扭力凸輪機構 所產生的軸方向的力量、利用線圈彈簧76所產生的軸 向的彈性力、以及朝向打開固定皮帶輪半體7 2及可動 帶輪半體7 3之間的間隔的方向作用的來自於V型皮帶 的力量的平衡性所決定的，在驅動皮帶輪5 8，藉由使可 皮帶輪半體63接近於固定皮帶輪半體62，而V型皮帶 的朝向驅動皮帶輪5 8的繞掛半徑變大時，V型皮帶60 朝向從動皮帶輪5 9的繞掛半徑就會變小。 在上述蓋板54及內側箱體52，是可自由旋轉地支 著後輪WR的車軸7 9，從變速機箱體5 1所突出的車軸 的端部，是被結合於引擎主體1 1，而可自由旋轉地被支 在後輪WR的右側所配置的臂部8 0。 在齒輪室5 7內，是收容有：設置在輸出軸61及車 79之間的減速齒輪組8 1，該減速齒輪組8 1，是由：設 在輸出軸61的第一齒輪82、被設置在，與輸出軸61及 軸79平行，而可自由旋轉地被支承於內側箱體52及蓋 54的中間軸83，而與第一齒輪82嚙合的第二齒輪84、 置在中間軸83的第三齒輪85、以及與第三齒輪85嚙合 設置在車軸79的第四齒輪86所構成。 合 帶 帶 輪 74 方 皮 60 動 60 的 承 79 承 軸 置 車 板 設 而 -13- (10) (10)1272353 在變速機箱體5 1的外側箱體5 3的朝向上述驅動皮帶 輪5 8的部分的側壁部，是設置有：用來將冷卻空氣引入 到收容室5 6內的外氣引入口 8 8，在上述驅動皮帶輪5 8的 固定皮帶輪半體6 2的外周’是一體地設置有：用來使從 外氣引入口 8 8所引入的冷卻空氣分散於收容室5 6內的冷 卻風扇8 9 〇 變速機箱體5 1的外側面’是以箱體外殼9 G及隔音外 殻91所覆蓋，箱體外殼90 ’是包含配置上述外氣引入口 8 8的部分，是覆蓋著變速機箱體51的前半部外側面，是 在複數處位置鎖裝在變速機箱體51的外側箱體5 3，隔音 外殼9 1，在對應於從動皮帶輪5 9的側邊，覆蓋著變速機 箱體5 1的後半部外側面，是在複數處位置，被鎖裝在變 速機箱體5 1的外側箱體5 3。 並且在箱體外殻90的後緣部，是以覆蓋著隔音外殼 9 1的前緣部的方式，將箱體外殼90及隔音外殼9 1安裝在 變速機箱體5 1，在箱體外殼90的後部與變速機箱體5 1之 間夾著隔音外殻9 1的前部所設置的兩個轂部9 1 a .·，箱 體外殻90的後部及隔音外殼9 1的前部，則是藉由螺栓構 件92 · •而一起被鎖裝到變速機箱體5 1。並且在箱體外 殻9 0的後緣部及隔音外殼9 1的前緣部之間，形成有朝後 方側開啓的吸入口 93，在箱體外殻90及變速機箱體5 1之 間，形成有與吸入口 93連通的空氣導入室94。 是以從空氣導入室94側封閉住上述外氣引入口 88的 方式，將過濾器9 5安裝在變速機箱體5 1的外側面，從吸 -14 - (11) 1272353 入口 93被導入至空氣導入室94的外氣，會藉由通過過 器9 5而被淨化，然後被吸入至收容室5 6。 在變速機箱體5 1及隔音外殼9 1之間，是配設有例 四個隔音構件99、100、1〇1、102，是將變速機箱體51 隔音外殻9 1之間的空間區隔成例如三個封閉空間96、 、98 ° 各隔音構件99〜102，是藉由聚氨酯薄片的切斷成 處理而分別形成爲帶狀，這些隔音構件99〜102的其中 面，是藉由黏接劑黏接到變速機箱體5 1或隔音外殼9 1 在實施例中則是黏接到隔音外殼9 1的內面部。 在變速機箱體5 1及隔音外殼9 1之間的空間，是藉 利用隔音構件99〜102將其區劃成複數的封閉空間96〜 ，則從變速機箱體51所放出的噪音，會被變速機箱體 及隔音外殻91之間所配置的隔音構件99〜102所吸收 被抑制，並且能抑制且防止聲音在變速機箱體5 1及隔 外殼9 1之間所形成的複數的封閉空間9 6〜9 8產生共鳴 象’以簡單的構造而能得到充分的防止噪音的效果。 在第3圖，在曲軸16上的面對於變速機箱體5 1內 收容室5 6的部分，是設置有面對於外側的環狀段部1 6a 在不能繞該曲軸1 6的軸線旋轉且同軸地圍繞曲軸1 6的 筒狀的套筒1 04的內端以及上述環狀肩部1 6a之間，是 著具有密封部的滾珠軸承1 05的內輪部。在曲軸1 6的 端部螺合著螺母1 06，驅動皮帶輪5 8的固定皮帶輪半 62，是不能相對旋轉地被安裝在曲軸1 6，並且被夾在： 濾 如 及 97 形 由 98 5 1 且 •g. 現 的 ， 圓 夾 外 體 抵 -15- (12) 1272353 接於螺母1 Ο 6的墊片1 Ο 7及套筒1 04的外端之間，藉由鎖 裝上螺母106，來將固定皮帶輪半體62固定在曲軸16。 驅動皮帶輪58的可動皮帶輪半體63，是一體地具有 :同軸地圍繞上述套筒1 〇 4的圓筒部6 3 a，在朝向軸方向 延伸而設置在圓筒部63a的圓周方向一處位置的導引孔 108，是嵌合著：卡合於上述套筒104的鍵部109。藉此， 可動皮帶輪半體63，是不能繞著軸線旋轉，並且可朝軸線 方向相對移動地，被安裝在套筒104也就是曲軸16。並且 由於導引孔108是設置在圓筒部63a的圓周方向一處位置 ，所以可將鍵部1 09及鍵溝部之間的餘隙設定得較小，能 夠減輕由於晃動而施加於鍵部1 〇 9的負荷。而在上述圓筒 部63a的內端部及套筒104之間，是中介安裝著環狀的密 封構件1 1 0。 在可動皮帶輪半體63，是以在軸線方向不能相對移動 但可相對旋轉的方式，安裝著：同軸地圍繞該圓筒部6 3 a 的圓筒狀的支承筒1 1 1，在從軸方向兩側夾著上述導引孔 1 0 8的兩處位置，是在圓筒部6 3 a及支承筒1丨1之間，安 裝著環狀的密封構件1 1 2、1 1 2。 在上述支承筒1 1 1的外周，是以不能朝軸方向相對移 動的方式，安裝著：具有密封部的滾珠軸承1 1 3的內輪部 ，該滾珠軸承1 1 3的外輪部，是以不能朝軸方向相對移動 的方式，被保持在減速齒輪機構6 6的從動齒輪也就是滑 動齒輪1 1 4的一端部內周。也就是說，可朝向曲軸1 6的 軸線方向移動的滑動齒輪11 4的其中一端部，是藉由經由 a -16- (13) (13)1272353 1 (2) In the case of the structure disclosed in Patent Document 1, a large outer casing is used to cover the entire sliding gear and the screwing portion of the sliding gear and the threaded shaft. Therefore, when such a large outer casing is housed in the transmission case, the size of the transmission case is increased. The sealing member is used to prevent dust from intruding into the sliding bearing portion of the sliding gear, and if the sliding gear and the screw portion of the hub are covered with a small outer casing, the inner circumference of the outer casing and the outer circumference of the sliding gear are interposed. When the φ ring seal member is installed, the size of the transmission housing can be prevented from increasing. In order to rapidly change the shifting section from the TOP toward the LOW side, when the movable pulley half of the drive pulley is rapidly moved toward the side of the width of the belt groove, the end of the sliding gear facing the opposite side of the movable pulley On the other hand, the volume of the annular chamber formed in the outer casing is rapidly contracted, and the sealing function of the inner peripheral portion of the outer casing and the outer periphery of the sliding gear may be damaged by the sudden pressure increase in the annular chamber. SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances, and an object thereof is to provide a V-belt type stepless speed changer which can be prevented from being enlarged by a small outer casing without being drastically pressurized. The sealing function of the sealing member between the inner circumference of the outer casing and the outer circumference of the sliding gear is damaged. [Means for Solving the Problem] In order to achieve the above object, the first invention is that a movable pulley half body constituting a drive pulley together with a fixed pulley half fixed to an input shaft is wound to transmit power to an output shaft. The circulating V-belt on the driven pulley side is installed, and it is possible to change the width of the belt groove formed between the half--6-(3) (3) 1272353 body of the fixed pulley. The input shaft is coupled to the input shaft while being relatively movable in the axial direction and not rotatable relative to each other; and the movable pulley half body ' is relatively movable in the axial direction and relatively rotatable about the axis. One end portion of the sliding gear that slides in the axial direction is such that the position in the axial direction and the position around the axis are constant, and the sliding is screwed on the outer circumference of the cylindrical screw shaft disposed coaxially with the input shaft. a V-belt type stepless speed changer of an inner circumference of a gear, characterized in that: an end wall portion fixed to the threaded shaft is formed into a bottomed cylindrical shape, and An inner circumferential surface of the outer casing covered by the sliding gear and the screw portion of the screw shaft and an outer circumference of the sliding gear are interposed with an annular sealing member so as to face the other end portion of the sliding gear. Further, the annular chamber formed in the outer casing is communicated to the outer communication hole, and is provided in the screw shaft or the outer casing. According to a second aspect of the invention, in the first aspect of the invention, the axial direction of the input shaft is constant, and the rotation axis direction of the screw shaft around the input shaft coaxially around the axis is positioned. The anti-vibration member is interposed between it and the transmission housing. [Effect of the Invention] The screwing portion of the sliding gear and the threaded shaft is covered by the outer casing, and the annular sealing member is interposed between the inner circumference of the outer casing and the outer circumference of the sliding gear by using a small outer casing. This prevents the operation from being unsmooth due to the intrusion of dust, and can prevent the size of the transmission housing from becoming large. And 1272353 κ (4) and since the annular chamber in the outer casing is connected to the outside via the communication hole, the situation in which the annular chamber is rapidly pressurized can be avoided, and the inner circumference of the outer casing is not caused by the sharp pressurization. And the sealing function of the sealing member between the outer circumferences of the sliding gears is damaged. According to the second aspect of the invention, the load in the axial direction of the screw shaft does not act on the anti-vibration member, and the load in the rotational direction of the screw shaft acts on the anti-vibration member, so that the load can be extended. The life of the shock-proof member can reduce the size of the anti-vibration support structure of the threaded shaft. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to an embodiment of the present invention. 1 to 9 are views showing an embodiment of the present invention, and Fig. 1 is a side view of the power unit and the rear wheel, Fig. 2 is a sectional view taken along line 2-4 of Fig. 1, and Fig. 3 is LOW The state shows an enlarged view of the vicinity of the drive pulley ί of Fig. 2, and Fig. 4 is a side view of the bolt shaft and the support plate viewed from the side of the movable pulley, and Fig. 5 is a cross-sectional view corresponding to Fig. 3 of the TOP state. Fig. 6 is a cross-sectional view showing a part of the gear reduction mechanism in an enlarged manner, Fig. 7 is a sectional view taken along line 7-7 of Fig. 6, and Fig. 8 is a view of the outer casing member viewed from the same direction as Fig. 7, Figure 9 is a view of the outer casing member as viewed from the side opposite to the eighth drawing. First, in the first and second figures, the engine E disposed in front of the drive wheel, that is, the rear wheel WR, and the V-belt type stepless speed changer provided between the engine E and the rear wheel WR are provided. The power unit -8- (5) 1272,353 yuan P is a rear body WR that is mounted on the rear side of the power unit P and is placed on the rear body of the power unit P. The shaft is supported at the rear of the power unit P. The engine main body 1 1 of the engine E is provided with a crankcase 1 rotatably supported by a crankshaft 16 having a rotation axis parallel to the rotation axis of the rear wheel WR 2, and a cylinder block coupled to the crankcase 1 2 .13. The cylinder head 14 coupled to the cylinder block 13 on the opposite side of the crankcase 12 and the cylinder head housing 15 coupled to the cylinder head 14 on the opposite side of the cylinder block 13. The cylinder block 13 is disposed such that the axis of the cylinder inner cylinder 17 provided in the cylinder block 13 is slightly horizontal toward the front upper direction in the front-rear direction of the locomotive. The crankcase 12 is composed of a pair of casing halves 1 2a and 12b combined in a plane including the cylinder axis and perpendicular to the axis of the crankshaft 16. In the two casing halves 12a, Between the case half body 1 2a and the crankshaft 16 of one of the 12bs, a ball bearing 18 is interposed, and between the other case half body 12b and the crankshaft 16, an intermediary is mounted: The sub-bearing 19 and the annular sealing member 20 disposed outside the roller bearing 19 are provided. In the cylinder inner cylinder 17, the piston 2 1 is slidably fitted, and the crankshaft 16 is coupled to the piston 21 via the crank pin 37 and the connecting rod 38. A combustion chamber 23 is formed between the cylinder head 14 and the piston 2 1 , an intake valve 24 for controlling an intake condition of the combustion chamber 23, and an exhaust gas for controlling the combustion chamber 23 from the combustion chamber 23 The exhaust valve 25 in the case is arranged in a substantially V-shape on a projection plane that is perpendicular to the rotation axis of the crankshaft 16 and is disposed in the cylinder head 14. The -9-(6) 1272353 is also mounted on the left side of the cylinder head 14 in a state in which the spark plug 2 6 of the combustion chamber 23 is directed toward the front of the locomotive. Between the cylinder head 14 and the cylinder head housing 15 is a valve mechanism 30 that accommodates opening and closing of the intake valve 24 and the exhaust valve 25, and the valve mechanism 30 has a crankshaft 1 The axis parallel to the axis of 6 is rotatably supported by the cylinder head 14, and includes a cam shaft 27 having intake and exhaust cams 28 and 29. ® The driven sprocket 31 is fixed to one end of the cam shaft 27. On the other hand, at the crankshaft 16 at the outer side of the ball bearing 18, at the position corresponding to the driven sprocket 31, the first drive sprocket 32 is fixed, and the first drive sprocket 32 and The driven sprocket 3 1 is wound around a circulating cam chain 33, and the cam chain 33 is operatively housed in: formed by the cylinder block 13 , the cylinder head 14 , and the cylinder head housing 15 Inside the chain chamber 3 4 . The first drive sprocket 3 2, the driven sprocket 3 1 , and the cam chain 3 3 are rotationally driven by the cam shaft 27 at a number of revolutions of 1 /2 of the number of revolutions of the crankshaft 16. The second drive sprocket 40 is fixed to the crankshaft 16 on the outer side of the first drive sprocket 3 2 . On the other hand, the oil pumped from the lower portion of the crankcase 1 2 is pumped 4 1 (see Fig. 1), and the cooling water jacket 43 provided in the cylinder block 13 and the cylinder head 14 is used to cool the water. The circulating cooling water pump 42 (see Fig. 1) is coaxially connected to the lower portion of the crankcase 12, and transmits rotational power from the second drive sprocket 40 via a chain (not shown). The oil pump 41 and the cooling ice pump 42 described above. Further to the outside of the second drive sprocket 40, a generator 46 -10- (7) 1272353 is provided, which is provided with a right outer casing that is fixed to the right side of the crankcase 1 2 The stator 47 of the 45, and the type surrounding the stator 47, are fixed to the outer rotor 48 of the crankshaft 16. Between the second drive sprocket 40 and the outer rotor 48, a driven gear 49 is disposed that coaxially surrounds the crankshaft 16 and is relatively rotatable about the crankshaft 16. The driven gear 49 It is connected to the outer rotor 48 via a one-way clutch. The driven gear 49 can be input from a rotary power of a starter motor (not shown), and when the engine E is started, the driving force from the starter motor is transmitted to the crankshaft 16. After the start of the starter E, By the actuation of the one-way clutch 50, the power from the song 16 is not transmitted to the starter motor side. The V-belt type stepless transmission Μ is a accommodating chamber 5 accommodated in the shifting casing body. The shifting housing body 5 1 covers a part of the engine body 11 from the side and is connected to the engine main body 1 1 . And extending the left side of the rear wheel WR, the shifting housing 5 is composed of an inner case 52 that is integrally connected to the case half 12b of the pair of case half bodies 12a, 12b constituting the crankshaft 12. The outer body 53 covering the inner case 52 from the outer side, the plate 54 locked to the rear portion of the inner case 52 in the outer case S3, and the front portion sandwiched between the inner case 52 and the outer case 53 The reduction gear case body 5 is formed; between the inner case body 52 and the cover plate 5, a gear chamber 57 is formed which is separated from the storage chamber 56. The V-belt type stepless speed change machine M is a drive pulley 58 mounted on the other end portion of the crankshaft 16 as an input shaft from the crankcase i 2 into the accommodating chamber 56, having a crankshaft 】6 parallel axis, when there is 50 on the inner side, the shaft 5 1 main to the box cover between the cover -11 - (8) (8) 1272353 box 5 2 and cover 5 4 The driven pulley 57 mounted on the output shaft 61 that is rotatably supported, and the circulating V-belt 60 that transmits power from the drive pulley 58 to the driven pulley 59 are formed. The drive pulley 58 is provided with a fixed pulley half 62 fixed to the crankshaft 16 and a movable pulley half 63 that is detachable and disengageable relative to the fixed pulley half 62 to allow the V-belt to be wound. In order to change the width of the belt groove 64 formed between the fixed pulley half 62 and the movable pulley half 63, the power of the movable pulley half 63 to be driven in the axial direction is installed in the shifting chassis. The electric motor 65 of the body 5 1 is transmitted to the movable sheave half 63 via the gear reduction mechanism 66. The driven pulley 59 is slidably provided in such a manner that the output shaft 61 is coaxially rotatable about the inner tubular portion 70 so as to be relatively rotatable about the axis and relatively movable in the axial direction. The outer tubular portion 71 of the fitting inner tubular portion 70, the fixed pulley half 72 fixed to the inner tubular portion 70, and the movable sheave half 73 fixed to the outer tubular portion 71 with respect to the fixed pulley half 72 are adapted to The relative rotational phase difference between the movable sheave half body 73 and the fixed sheave half 72 is such that the axial direction component acts between the two pulley halves 72, 73 and is disposed in the inner tubular portion 70 and the outer cylinder. The torsion cam mechanism 74 between the portions 71 is fixed to the spring seat member 75 of the inner tube portion 70 and around the outer tube portion 7 at a position sandwiching the movable pulley half 73 between the fixed pulley half 72 and the fixed pulley half 72. 1 , the coil spring 76 which is compressed between the movable sheave half body 73 and the spring seat member 75, and the state in which the number of revolutions of the engine exceeds the set number of revolutions becomes the power transmission -12-(9) 1272353 state, and is Provided in the inner cylinder portion 70 and the output shaft 6 1 The intermediate centrifugal device 77; the belt groove 78 formed between the fixed pulley half 72 of the drive pulley 58 and the movable pulley half 73 is wound around the V-shaped skin 60° and the driven pulley 59 The interval between the fixed pulley half body 7 2 and the movable belt half body 7 2 is obtained by the axial direction force generated by the above-described torque cam mechanism, the axial elastic force generated by the coil spring 76, and the orientation. The balance of the force from the V-belt acting in the direction of the interval between the fixed pulley half 7 2 and the movable pulley half 7 3 is determined by the drive pulley 5 8 by the pulley pulley half 63 is close to the fixed pulley half 62, and when the winding radius of the V-belt toward the drive pulley 58 becomes larger, the winding radius of the V-belt 60 toward the driven pulley 59 becomes smaller. The cover plate 54 and the inner case 52 are rotatably supported by the axle 7 of the rear wheel WR, and the end of the axle protruding from the shift case 51 is coupled to the engine body 1 1 . The arm portion 80 disposed on the right side of the rear wheel WR is rotatably supported. In the gear chamber 57, a reduction gear set 810 is provided which is disposed between the output shaft 61 and the vehicle 79. The reduction gear set 181 is composed of a first gear 82 provided on the output shaft 61, and is It is disposed in parallel with the output shaft 61 and the shaft 79, and is rotatably supported by the inner casing 52 and the intermediate shaft 83 of the cover 54, and the second gear 84 meshing with the first gear 82 is disposed on the intermediate shaft 83. The third gear 85 and the fourth gear 86 that meshes with the third gear 85 are disposed on the axle 79. The belt pulley 60 is formed by the 60-seat 60-seat 60-seat axle plate and the -13-(10) (10) 1272353 is on the outer casing 53 of the shifting housing body 5 1 facing the drive pulley 58. A portion of the side wall portion is provided with an external air introduction port 8 for introducing cooling air into the accommodating chamber 56, and an outer periphery of the fixed pulley half 6 2 of the drive pulley 58 is integrally provided The cooling fan for dispersing the cooling air introduced from the external air introduction port 8 in the accommodating chamber 56 is disposed on the outer side of the shifting housing 5 1 as the casing 9 G and the soundproof casing 91. Covered, the casing casing 90' is a portion including the outer air introduction port 88, and covers the outer side of the front half of the shifting housing 51, and is locked to the outer casing of the shifting housing 51 at a plurality of positions. 5 3, the soundproof casing 9 1, on the side corresponding to the driven pulley 59, covering the outer side of the rear half of the shifting housing 51, is locked at the outer side of the shifting housing 5 1 at a plurality of positions The box body 5 3 . Further, at the rear edge portion of the casing casing 90, the casing casing 90 and the soundproof casing 9 1 are attached to the shift casing body 5 1 in the casing casing 90 so as to cover the front edge portion of the soundproof casing 9 1 . The rear portion and the shifting housing body 51 are sandwiched between the two hub portions 9 1 a of the front portion of the soundproof housing 9 1 , and the rear portion of the housing shell 90 and the front portion of the soundproof housing 9 1 are borrowed. It is locked together with the shifting housing body 5 1 by the bolt members 92 · •. Further, between the rear edge portion of the casing casing 90 and the front edge portion of the soundproof casing 9 1 , a suction port 93 that opens toward the rear side is formed, and between the casing casing 90 and the shift casing 5 1 is formed between The air that communicates with the suction port 93 is introduced into the chamber 94. The filter 95 is attached to the outer side surface of the shift case body 5 1 so as to be closed to the air from the air introduction chamber 94 side, and is introduced into the air from the suction port 14 - (11) 1272353 inlet 93. The outside air introduced into the chamber 94 is purified by the passager 95 and then sucked into the storage chamber 56. Between the shifting housing body 5 1 and the sound insulating housing 9 1 , four types of sound insulating members 99 , 100 , 1 , 1 , 102 are provided to separate the space between the soundproof housings 9 1 of the shifting housing 51 . For example, the three soundproof members 99 to 102 of the three closed spaces 96 and 98 are formed into strips by the cutting process of the urethane sheets, and the inner faces of the sound insulating members 99 to 102 are bonded by means of bonding. The agent is bonded to the shifting housing body 5 1 or the soundproof housing 9 1 in the embodiment to be bonded to the inner surface of the soundproof housing 9 1 . The space between the shifting housing 5 1 and the sound insulating housing 9 1 is divided into a plurality of closed spaces 96 to 9 by the sound insulating members 99 to 102, and the noise emitted from the shifting housing 51 is changed by the shifting chassis. The absorption of the soundproof members 99 to 102 disposed between the body and the soundproof casing 91 is suppressed, and a plurality of closed spaces 9 6 to be formed between the shifting housing 5 1 and the partition housing 9 1 can be suppressed and prevented from being sounded. 9 8 produces a resonance image with a simple structure to obtain a sufficient noise prevention effect. In Fig. 3, the portion of the crankshaft 16 on the portion of the accommodating chamber 56 in the shifting housing 51 is provided with a surface-to-outer annular portion 16a that is rotatable about the axis of the crankshaft 16 and coaxial. Between the inner end of the cylindrical sleeve 104 of the crankshaft 16 and the annular shoulder 16a, the inner ring portion of the ball bearing 156 having the seal portion is formed. The nut 106 is screwed to the end of the crankshaft 16 and the fixed pulley half 62 of the drive pulley 58 is mounted on the crankshaft 16 in a relatively rotatable manner and is clamped in: Filtered and 97-shaped by 98 5 1 And • g. Now, the outer body of the round clamp is -15- (12) 1272353. It is connected between the gasket 1 Ο 7 of the nut 1 Ο 6 and the outer end of the sleeve 104, and the nut 106 is locked by the lock. The fixed pulley half 62 is fixed to the crankshaft 16. The movable sheave half 63 of the drive pulley 58 integrally includes a cylindrical portion 630 a that coaxially surrounds the sleeve 1 〇4, and is disposed at a position in the circumferential direction of the cylindrical portion 63a so as to extend in the axial direction. The guide hole 108 is fitted with a key portion 109 that is engaged with the sleeve 104. Thereby, the movable sheave half 63 is rotatable about the axis and is relatively movable in the axial direction, and is attached to the sleeve 104, that is, the crankshaft 16. Further, since the guide hole 108 is provided at a position in the circumferential direction of the cylindrical portion 63a, the clearance between the key portion 109 and the key groove portion can be set small, and the application to the key portion 1 due to the sway can be reduced. 〇 9 load. On the other hand, between the inner end portion of the cylindrical portion 63a and the sleeve 104, an annular sealing member 110 is interposed. In the movable sheave half 63, a cylindrical support cylinder 1 1 1 coaxially surrounding the cylindrical portion 6 3 a is attached so as not to be relatively movable in the axial direction but relatively rotatable in the axial direction At two positions sandwiching the above-mentioned guide holes 108, the annular sealing members 1 1 2, 1 1 2 are attached between the cylindrical portion 633a and the support cylinder 1丨1. On the outer circumference of the support cylinder 1 1 1 , an inner wheel portion of a ball bearing 1 1 3 having a seal portion is attached so as not to be relatively movable in the axial direction, and the outer ring portion of the ball bearing 1 1 3 is The driven gear that is held by the reduction gear mechanism 66, that is, the inner circumference of one end portion of the slide gear 1 14 is not movable in the axial direction. That is, one end portion of the sliding gear 11 4 which is movable toward the axial direction of the crankshaft 16 is by a-16-(13) (13)
1272353 上述具有密封部的滾珠軸承1 1 3 ’而以7 移動且可繞著軸線相對旋轉的方式，被_ 帶輪半體63。 上述具有密封部的滾珠軸承1 0 5的夕' 軸方向相對移動地被保持在：同軸地圍繞 狀的螺紋軸115的內周。也就是說’螺宏 位預定的軸方向位置的方式’同軸地圍繞 紋軸1 1 5的外周，是刻設有例如三條的虫j ，而將上述滑動齒輪11 4的另一端部內周 軸1 1 5的外周。 合倂參照第4圖，在上述螺紋軸1 1 5 承板1 1 8，在上述支承板1 1 8的從上述曲j 的位置，是固定安裝著：具有與曲軸1 6 筒狀的安裝筒1 1 9。 在上述安裝筒119，是***有：在外 震構件的圓筒狀的防震橡膠1 2 0的圓筒取 藉由將插通於該軸環1 2 1的螺栓1 2 2螺合 體5 1的內側箱體5 2，讓支承板1 1 8也葡 相對於螺紋軸1 1 5的繞著軸線的旋轉方向 橡膠120，被定位在變速機箱體51。 在被定位於曲軸1 6的軸線方向並且 旋轉的螺紋軸1 1 5處所螺合的滑動齒輪 動馬達6 5經由減速齒輪機構6 6所傳達的 此，可動皮帶輪半體63，會在第3圖所j :能朝軸方向相對 丨結在上述可動皮 、輪部，是不能朝 丨曲軸16的圓筒 t軸1 1 5，是以定 曲軸1 6，在該螺 !紋溝槽1 1 7 ·. 丨螺合於上述螺紋 是固定安裝著支 軸1 6的軸線偏置 平行的軸線的圓 周燒接有作爲防 ί的軸環1 2 1，是 -鎖裝於變速機箱 t是螺紋軸1 1 5， 丨，經由上述防震 不需要繞著軸線 1 1 4，會藉由從電 I動力而旋轉，藉 的LOW位置、 -17- 1272353 • (14) 與第5圖所示的Τ Ο P位置之間朝軸方向移動，在上述支承 板Π 8，是一體地設置有：藉由在LOW位置卡合於滑動齒 輪1 1 4，來限制可動皮帶輪半體63的朝向LOW位置側的 移動端的擋塊118a，而藉由在TOP位置卡合於滑動齒輪 1 1 4，而用來限制可動皮帶輪半體63的朝向TOP位置側的 移動端的擋塊1 2 8，是被固定安裝在變速機箱體5 1的內側 箱體5 2。 φ 上述螺紋軸1 1 5及上述滑動齒輪1 1 4的螺合部，是以 :具有被固定於螺紋軸115的端壁部116a而形成爲有底 圓筒狀的外殼1 1 6所覆蓋，在該外殻1 1 6的內周、與滑動 齒輪114的外周之間，是中介安裝有環狀的密封構件124 〇 在外殼1 1 6內，是形成有：使上述滑動齒輪1 1 4的另 一端部面對著的環狀室1 2 3，該環狀室1 2 3的容積，會因 應於可動皮帶輪半體63及滑動齒輪1 14在上述LOW位置 • 及在上述top位置之間朝軸方向移動的動作而變化。而爲 了使變速段從TOP朝向LOW側急速變化，當使可動皮帶 輪半體63朝向增大皮帶溝槽64的寬度的側邊急速移動時 .，環狀室1 23的容積會急劇收縮，藉由讓環狀室丨23內急 劇增壓，而有可能使外殻1 1 6的內周及滑動齒輪1 1 4的外 周間的密封構件1 24的密封機能受損。 因此，爲了要使上述環狀室1 2 3連通到：以套筒1 0 4 的外周、螺紋軸1 1 5的內周、滑動齒輪1 1 4的內周、可動 皮帶輪半體6 3的圓筒部6 3 a的內端部、及支承筒1 1 1的 -18- (15) (15)1272353 外周部所限定的空室部1 25側，是在螺紋軸Π 5的側壁部 設置有其中一端部連通於上述環狀室123的連通孔126, 並且在螺紋軸1 1 5的內周’設置有：使該連通孔1 2 6的另 —端連通於上述空室部125的凹部127。 上述空室部125的容積’也是因應於可動皮帶輪半體 6 3及滑動齒輪1 1 4在上述L 〇 W位置及上述Τ Ο Ρ位置間朝 軸方向移動的情形而變化，而當使變速段從TOP朝向 L 0 W側變化時的上述空室部1 2 5的容積變化比例，是小於 上述環狀室1 23的容積變化比例，而當使變速段從TOP朝 向LOW側變化時的環狀室123的壓力增壓程度，是藉由 讓環狀室1 2 3連通到空室部1 2 5，而被抑制得較小。 合倂參照第6圖，齒輪減速機構6 6，至少具備有：與 電動馬達6 5同軸相連的驅動齒輪1 3 0、以及將與該驅動齒 輪1 3 0嚙合的大齒輪1 3 1及小齒輪1 3 2 —體地設置於怠速 旋轉軸1 3 3所構成的怠速齒輪1 3 4，在該實施例，上述齒 輪減速機構66，又具備有：設置於上述小齒輪132及上述 滑動齒輪1 1 4之間的第二怠速齒輪1 3 5，該第二怠速齒輪 1 3 5，是以：與上述小齒輪1 3 2嚙合的大齒輪1 3 6、以及與 大齒輪1 3 6 —體形成而嚙合於滑動齒輪1 1 4的小齒輪1 3 7 所構成。 構成變速機箱體5 1的一部分的內側箱體5 2及減速齒 輪箱體5 5，是形成爲：讓其一部分較外側箱體5 3朝向氣 缸頭1 4也就是前方側突出，在減速齒輪箱體5 5的周壁部 5 5 a之中的較外側箱體5 3朝向前方突出的部分’是將作成 -19- 1272353 • (16) 限定大致半周的貫穿孔1 3 8設置於減速齒輪5 5。另一方面 ’在減速齒輪箱體5 5的外面部，是以複數的螺栓1 4 0 · · 鎖裝著安裝板1 3 9，該安裝板1 3 9，具有氣密性地嵌入於 上述貫穿孔138的圓筒部139a，將具有與曲軸16平行的 軸線的旋轉軸1 4 1的電動馬達6 5固定在安裝板1 3 9，上述 旋轉軸1 4 1是貫穿上述圓筒部丨3 9a而突入於變速機箱體 51內。並且驅動齒輪1 3 0是一體地形成於旋轉軸1 4 1。 # 在減速齒輪箱體5 5及內側箱體5 2，是以同軸且互相 相對向的方式，一體地突出設置有：用來可自由旋轉地支 承著怠速齒輪1 3 4所具備的怠速旋轉軸1 3 3的兩端部的圓 筒狀的軸承殻體1 42、1 43，上述怠速旋轉軸1 3 3的兩端部 ，是經由滾珠軸承1 44、1 45而可自由旋轉地被支承在上 述兩軸承殻體1 4 2、1 4 3。 在減速齒輪箱體5 5的內面部，是一體地突出設置有 壁部5 5 b，該壁部5 5 b，是與減速齒輪5 5的周壁部5 5 a的 # 一部分共同圍繞：與電動馬達6 5相連的驅動齒輪1 3 0、以 及構成怠速齒輪1 3 4的一部分而嚙合於驅動齒輪1 3 0的大 齒輪1 3 1。 在減速齒輪箱體55，是安裝有外殼構件147 ;將上述 驅動齒輪1 3 0及上述大齒輪1 3 1從變速機箱體5 1內的收 容室56區隔開來而予以收容的減速齒輪室146，是形成在 外殻構件147與上述減速齒輪箱體55之間。 合倂參照第7圖〜第9圖，是將外殼構件1 47形成爲 :覆蓋著減速齒輪箱體5 5的上述壁部5 5 b的端部並且與 -20- (17) 1272353 上述周壁部5 5 a的內周相對向，在該外殼構件；[4 7的周緣 部，是燒接有：抵接於上述壁部5 5 b的端部並且接觸於上 述周壁部5 5 a的內面的密封橡膠1 4 8。 在減速齒輪箱體5 5，在上述壁部5 5 b、與該壁部5 5 b 的外側內面，是設置有安裝部1 4 9、1 5 0，在外殼構件1 4 7 ，是一體地設置有：以與上述安裝部1 4 9所抵接的平坦的 安裝腕部147a及上述安裝部1 50相抵接的方式彎曲的安 • 裝腕部147b，藉由將分別設置於安裝腕部147a、147b的 插通孔1 5 1 · ·所插通的螺栓1 5 2 ··螺合鎖裝在上述安 裝部149、150，來將外殼構件147安裝於減速齒輪箱體 55 ° 在外殼構件147，是以突入於減速齒輪室146內的方 式，一體地突出設置有圓筒部147c，該圓筒部147c是形 成有用來讓怠速齒輪1 3 4的小齒輪1 3 2貫穿用的圓形的開 口部1 5 3 ;是藉由讓該圓筒部1 4 7 c的前端部，***到在上 ® 述怠速齒輪1 3 4的大齒輪1 3 1所設置的環狀溝槽1 3 1 a，而 在外殼構件1 4 7及上述大齒輪1 3 1之間形成有迷宮式通路 154° 再看第3圖及第5圖，第二怠速齒輪135，是在變速 機箱體51的內側箱體5 2及減速齒輪箱體5 5可自由旋轉 地支承其兩端部的金屬製的旋轉軸1 5 6，以銷栓1 5 7及固 定輪1 5 8限制其朝軸方向移動’所被安裝的構造。 並且在上述旋轉軸1 5 6的減速齒輪箱體5 5側端部， 是一體地設置有齒輪〗65，在上述減速齒輪箱5 5可自由旋 -21 - (18) 1272353 • » 轉地被支承的行程感應器軸1 6 6所設置的禍彳干1 6 7 ’是被 嚙合在上述齒輪1 65。行程感應器軸1 66 ’是與沒有圖示 的行程感應器相連的構造’由於是在構成減速齒輪機構6 6 的一部分的第二怠速齒輪1 3 5的旋轉部分’檢測出驅動皮 帶輪5 8的可動皮帶輪半體63的行程’所以可提高驅動皮 帶輪5 8的維修性，且能提高行程檢測精確度。 構成減速齒輪機構6 6的驅動齒輪1 3 0、怠速齒輪1 3 4 • 、第二怠速齒輪1 3 5、及滑動齒輪Π 4之中’第二怠速齒 輪1 3 5，是藉由自我潤滑性樹脂所形成，驅動齒輪1 3 0、 怠速齒輪1 3 4、及滑動齒輪1 1 4，是金屬製的。 接著針對該第一實施例的作用來加以說明’在構成驅 動皮帶輪5 8的一部分的可動皮帶輪半體63，是以不能朝 軸方向相對移動且可繞著軸線相對旋轉的方式，連結著可 朝曲軸1 6的軸線方向滑動的滑動齒輪1 1 4的其中一端部 ’是以讓軸方向位置及軸線周圍的位置成爲一定的方式， ® 在與曲軸16同軸配置的圓筒狀的螺紋軸1 1 5的外周，螺 合著滑動齒輪1 1 4的內周，而在··具有固定於螺紋軸1 1 5 的端壁部116a，形成爲有底圓筒狀，並且將滑動齒輪U4 及螺紋軸1 1 5的螺合部予以覆蓋的外殼1 1 6的內周、以及 滑動齒輪1 1 4的外周之間，是中介安裝著環狀的密封構件 124° 於是藉由使用較小的外殼11 6，可防止由於灰麈的侵 入而讓滑動齒輪1 1 4及螺紋軸1 1 5的螺合部的作動情形變 得不順暢的情形，而可避免讓變速機箱體5 1大型化。 - 22- (19) 1272353 « . 並且由於使面對著滑動齒輪i14的另一端部’並且將 外殻1 1 6內所形成的環狀室1 23連通到外部的空室部1 25 的連通孔1 26，設置在螺紋軸1 1 5 ’所以能避免環狀室1 23 急劇增壓的情形，而不會由於急劇的增壓’而讓外殼1 1 6 的內周及滑動齒輪1 1 4的外周間的密封構件1 2 4的密封機 能受損。 將相對於曲軸1 6的軸方向位置設爲一定’且同軸地 • 圍繞該曲軸1 6的上述螺紋軸1 1 5，相對於其軸線周圍的旋 轉方向，是將防震橡膠120中介於其與變速機箱體51的 內側箱體52之間來予以定位，所以從滑動齒輪1 1 4所受 到的負荷之中，沿著螺紋軸1 1 5的軸方向的負荷’不會作 甩於防震橡膠1 2〇，而只有螺紋軸1 15的旋轉方向的負荷 作用於防震橡膠1 2 0，所以可延長防震橡膠1 2 0的使用壽 命，能夠使螺紋軸1 1 5的防震支承構造小型化。 設置在電動馬達6 5、與驅動皮帶輪5 8的可動皮帶輪 • 半體6 3之間，而被收容於變速機箱體5 1的減速齒輪機構 6 6，是至少具備有：與電動馬達6 5同軸相連的驅動齒輪 1 3 0、以及將嚙合於該驅動齒輪1 3 0的大齒輪1 3 1及小齒 輪1 3 2 —體地設置於怠速旋轉軸1 3 3所構成的怠速齒輪 1 34，將驅動齒輪1 3 0及大齒輪1 3 1從變速機箱體5 1內的 收容室5 6區隔開來而予以收容的減速齒輪室1 46，是形成 在外殼構件1 4 7與變速機箱體5 1的減速齒輪箱體5 1之間 ，該外殼構件1 47，是以在與大齒輪1 3 1之間’形成迷宮 式通路1 54並且形成讓小齒輪1 32貫穿的開口部1 53的方 -23- (20) 1272353 式，被安裝在變速機箱體5 1的減速齒輪箱體5 5，所 減速齒輪機構6 6 ’能以較小的外殼構件1 4 7，來防止 侵入到嚙合次數較多的驅動齒輪1 3 0及怠速齒輪1 3 4 合部，能避免變速機箱體5 1大型化，且能提升減速 機構66的使用壽命。 在構成變速機箱體51的一部分的減速齒輪箱體 是設置有：可自由旋轉地支承著怠速旋轉軸1 3 3的其 端部的軸承殼體1 42，並且設置有外殼構件1 47的安 1 4 9、1 50，所以能將迷宮式通路1 5 4形成得較小，而 升密封性能。如該實施例，當在減速齒輪箱體5 5及 箱體5 2，可自由旋轉地支承著怠速齒輪1 3 4的怠速旋 1 3 3的兩端部時，當進行V型皮帶式無段變速機Μ的 時，藉由以外殼構件1 74將怠速齒輪1 3 4保持在減速 箱體5 5側防止其脫落，可提高組裝性。 減速齒輪機構66，是包含有：被中介安裝在金屬 怠速齒輪1 3 4的小齒輪1 3 2及滑動齒輪1 1 4之間而藉 我潤滑性樹脂所形成的第二怠速齒輪1 3 5，在減速齒 構66的在減速齒輪室146外的齒輪嚙合部，可進行 潤滑，而可將潤滑構造簡化，在變速機箱體5 1內， 樹脂製的第二怠速齒輪1 3 5配置在減速齒輪室1 4 6外 寬廣的空間，而可提高冷卻性。 第 1 〇圖是顯示本發明的第二實施例，被定位在 1 6的軸線方向且不需要繞著軸線旋轉的螺紋軸1 1 5及 齒輪1 1 4的螺合部，是以：具有固定於螺紋軸1 ] 5的 以在 灰塵 的嚙 齒輪 55， 中一 裝部 能提 內側 轉軸 組裝 齒輪 製的 由自 輪機 樹脂 會將 的較 曲軸 滑動 端壁 -24- 1272353 . (21) 部Π 6a且形成爲有底圓筒狀的外殼1 1 6所覆蓋’在該外 殼1 1 6的內周、與滑動齒輪1 1 4的外周之間，是中介安裝 著環狀的密封構件124。 爲了使面對著滑動齒輪1 1 4的另一端部而形成於外殻 1 1 6內的環狀室1 2 3，連通於變速機箱體5 1內的收容室5 6 ，而將其中一端部連通到上述環狀室1 2 3的上部的連通孔 1 5 9，是被設置在外殻1 1 6的端壁部1 1 6a及支承板1〗8 ’ • 在支承板1 1 8的外面部，是固定安裝著··覆蓋上述連通孔 159的另一端，並且朝向上方開口的連通孔外殼160。 在該第二實施例，爲了要使變速段急速地從TOP變化 到LOW側，而藉由使可動皮帶輪半體63急速地朝向增大 皮帶溝槽64的寬度側移動，而即使環狀室123的容積急 劇收縮，也能抑制環狀室1 23的增壓情形，而不會由於急 劇的增壓而讓外殻1 1 6的內周及滑動齒輪1 1 4的外周間的 密封構件1 2 4的密封機能受損。 # 以上，雖然說明本發明的實施例，可是本發明並不限 定於上述實施例，只要不脫離申請專利範圍所記載的本發 明，可進行種種的設計變更。 【圖式簡單說明】 第1圖是第一實施例的動力單元及後輪的側面圖。 第2圖是第1圖的2 - 2線剖面圖。 第3圖是以LOW狀態來顯示第2圖的驅動皮帶輪附 近的放大圖。 -25- (22) 1272353 第4圖是從可動皮帶輪側來觀察螺紋軸及支承板的側 面圖。 第5圖是在T0P狀態的與第3圖對應的剖面圖。 第6圖是將齒輪減速機構的一部分放大顯示的剖面圖 〇 第7圖是第6圖的7 一 7線剖面圖。 第8圖是從與第7圖同一方向來觀察外殼構件的視圖 第9圖是從第8圖的相反側來觀察外殼構件的視圖。 第1 0圖是第二實施例的對應於第3圖的剖面圖。 【主要元件符號說明】 1 6 :作爲輸入軸的曲軸 5 1 :變速機箱體 5 8 :驅動皮帶輪 ® 5 9 :從動皮帶輪 61 :輸出軸 62:固定皮帶輪半體 63:可動皮帶輪半體 64 :皮帶溝槽 1 1 4 :滑動齒輪 1 1 5 :螺紋軸 1 1 6 :外殼 1 16a :端壁部1272353 The above-described ball bearing 1 1 3 ' having a seal portion is moved by 7 and relatively rotatable about the axis, and is carried by the pulley half body 63. The above-described axial direction of the ball bearing 105 having the seal portion is relatively moved in the inner circumference of the screw shaft 115 coaxially surrounding. That is to say, the manner of 'the predetermined axial direction position of the spiral macro position' coaxially surrounds the outer circumference of the groove 1 15 , is, for example, three insects j are engraved, and the other end portion of the above-mentioned sliding gear 11 4 is the inner peripheral axis 1 The outer perimeter of 1 5 . Referring to Fig. 4, at the position of the above-mentioned support plate 1 1 8 from the above-mentioned curve j, the above-mentioned threaded shaft 1 1 5 is fixedly mounted: a cylindrical tube having a cylindrical shape with the crankshaft 16 1 1 9. In the above-mentioned mounting cylinder 119, a cylinder of a cylindrical anti-vibration rubber 1 2 0 inserted in the external shock member is inserted inside the screw body 1 1 of the bolt 1 2 2 inserted through the collar 1 2 1 The casing 52 is positioned such that the support plate 1 18 is positioned in the shifting housing 51 with respect to the rotational direction rubber 120 about the axis of the threaded shaft 1 15 . In the case of the sliding gear motor 65 that is screwed at the threaded shaft 1 15 that is positioned in the axial direction of the crankshaft 16 and rotated, the movable pulley half 63 is conveyed via the reduction gear mechanism 66. j: can be relatively entangled in the axial direction in the movable skin, the wheel portion, can not face the cylinder t-axis 1 1 5 of the crankshaft 16, is the fixed crankshaft 16 in the spiral groove 1 1 7丨 合 于 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述 上述1 5, 丨, through the above shockproof does not need to be around the axis 1 1 4, will be rotated by the electric I, borrowed LOW position, -17-1272353 • (14) and Τ Ο P shown in Figure 5 The support plate Π8 is integrally provided with the movement of the movable pulley half 63 toward the LOW position side by being engaged with the slide gear 1 1 4 at the LOW position. The stopper 118a is used to restrict the movable pulley half body 63 by being engaged with the sliding gear 1 14 at the TOP position. TOP toward the movement end position side of the stopper 128, is fixedly mounted inside the transmission case 5 of the housing 152. φ The screwing portion of the threaded shaft 1 15 and the sliding gear 1 1 4 is covered by a casing 1 16 having a bottomed cylindrical portion that is fixed to the end wall portion 116a of the threaded shaft 115. Between the inner circumference of the outer casing 1 16 and the outer circumference of the sliding gear 114, an annular sealing member 124 is interposed in the outer casing 1 16 , and the sliding gear 1 1 4 is formed. The other end faces the annular chamber 1 2 3, and the volume of the annular chamber 1 2 3 is adapted to the movable pulley half 63 and the sliding gear 1 14 at the LOW position and between the above top positions. The movement in the axial direction changes. Further, in order to rapidly change the shifting section from the TOP toward the LOW side, when the movable sheave half 63 is rapidly moved toward the side where the width of the belt groove 64 is increased, the volume of the annular chamber 231 is sharply contracted by The inside of the annular chamber 23 is rapidly pressurized, and there is a possibility that the sealing function of the seal member 14 between the inner circumference of the outer casing 1 16 and the outer circumference of the sliding gear 1 14 is damaged. Therefore, in order to connect the above-mentioned annular chamber 1 2 3 to the outer circumference of the sleeve 1 0 4 , the inner circumference of the threaded shaft 1 15 , the inner circumference of the sliding gear 1 14 , and the circle of the movable pulley half 6 3 The inner end portion of the tubular portion 63 3 a and the empty chamber portion 15 side defined by the outer peripheral portion of the -18-(15) (15) 1272353 of the support cylinder 1 1 1 are provided on the side wall portion of the screw shaft Π 5 One end portion communicates with the communication hole 126 of the annular chamber 123, and the inner circumference 'of the threaded shaft 1 15 is provided with a recess 127 that allows the other end of the communication hole 1 26 to communicate with the empty chamber portion 125. . The volume ' of the empty chamber portion 125 is also changed in response to the movement of the movable sheave half 6 3 and the sliding gear 1 14 in the axial direction between the L 〇 W position and the Τ Ρ position, and when the shifting section is made The volume change ratio of the above-described empty chamber portion 1 2 5 when the TOP is changed toward the L 0 W side is smaller than the volume change ratio of the annular chamber 1 23, and is a ring shape when the shifting portion is changed from the TOP toward the LOW side. The degree of pressure pressurization of the chamber 123 is suppressed to be small by allowing the annular chamber 1 2 3 to communicate with the empty chamber portion 1 2 5 . Referring to Fig. 6, the gear reduction mechanism 66 is provided with at least a drive gear 1300 coaxially connected to the electric motor 65, and a large gear 1 3 1 and a pinion that meshes with the drive gear 1 30. In the embodiment, the gear reduction mechanism 66 is further provided on the pinion gear 132 and the sliding gear 1 1 . The gear reduction mechanism 66 is configured to be disposed on the idle gear 13 and the sliding gear 1 1 . a second idle gear 1 3 5 between the 4, the second idle gear 1 3 5 is a large gear 136 meshing with the pinion gear 132, and is formed integrally with the large gear 136 It is constituted by a pinion gear 1 3 7 that meshes with the slide gear 1 1 4 . The inner case 52 and the reduction gear case 55 which form part of the shift case body 5 1 are formed such that a part thereof protrudes toward the cylinder head 14 from the outer case 5 3 , that is, the front side, in the reduction gear box The portion of the peripheral wall portion 5 5 a of the body 5 5 that protrudes toward the front is formed in the reduction gear 5 5 by the through hole 1 3 8 which is formed to be substantially half a circumference. . On the other hand, in the outer surface portion of the reduction gear housing 55, a plurality of bolts 1 4 0 · · a mounting plate 139 are locked, and the mounting plate 139 is airtightly embedded in the above-mentioned through-hole. The cylindrical portion 139a of the hole 138 fixes the electric motor 65 having the rotating shaft 14 1 having an axis parallel to the crankshaft 16 to the mounting plate 139, and the rotating shaft 14 1 penetrates the cylindrical portion 丨39a. It protrudes into the shifting housing 51. And the drive gear 130 is integrally formed on the rotating shaft 14 1 . # The reduction gear case body 5 5 and the inner case body 5 2 are integrally provided so as to be coaxially opposed to each other so as to be rotatably supported by the idle rotation shaft of the idle gear 1 3 4 Cylindrical bearing housings 1 42 and 1 at both ends of 1 3 3, both ends of the idle rotating shaft 13 3 are rotatably supported by ball bearings 1 44 and 1 45 The above two bearing housings 1 4 2, 1 4 3 . In the inner surface portion of the reduction gear housing 55, a wall portion 5 5 b is integrally protruded, and the wall portion 5 5 b is surrounded by a part of the peripheral wall portion 5 5 a of the reduction gear 55: The drive gear 1 3 0 to which the motor 6 5 is connected, and the large gear 1 3 1 that constitutes a part of the idle gear 1 3 4 mesh with the drive gear 1 300. The reduction gear case 55 is provided with a casing member 147; a reduction gear chamber in which the drive gear 1300 and the large gear 133 are separated from the accommodating chamber 56 in the transmission case 5 1 and housed therein 146 is formed between the outer casing member 147 and the reduction gear case 55 described above. Referring to FIGS. 7 to 9 , the outer casing member 1 47 is formed so as to cover the end portion of the wall portion 55 b of the reduction gear box body 5 5 and the above peripheral wall portion of -20-(17) 1272353 The inner circumference of the 5 5 a is opposed to the inner surface of the outer casing member; [4 7 is burned with an end portion abutting against the wall portion 5 5 b and contacting the inner surface of the peripheral wall portion 55 a Sealing rubber 1 4 8. In the reduction gear box body 5 5 , the wall portion 5 5 b and the outer surface of the wall portion 5 5 b are provided with mounting portions 1 4 9 and 1 50, and the outer casing member 1 4 7 is integrated. The mounting arm portion 147b that is bent so as to be in contact with the flat mounting arm portion 147a and the mounting portion 150 that are in contact with the mounting portion 149 is provided on the mounting arm portion. Inserting holes 147a, 147b 1 5 1 · Bolts inserted 1 5 2 · Screws are attached to the mounting portions 149, 150 to mount the outer casing member 147 to the reduction gear housing 55 ° at the outer casing member 147 is integrally provided with a cylindrical portion 147c formed in a circular shape for inserting the pinion gear 1 3 2 of the idle gear 1 3 4 so as to protrude into the reduction gear chamber 146. The opening portion 1 5 3 is inserted into the annular groove 1 3 1 provided by the large gear 1 3 1 of the upper idle gear 1 3 4 by the front end portion of the cylindrical portion 1 4 7 c a, a labyrinth passage 154 is formed between the outer casing member 147 and the large gear 1 3 1 . Referring to FIGS. 3 and 5, the second idle gear 135 is The inner case 52 and the reduction gear case 55 of the shift case 51 rotatably support the metal rotary shafts 156 at both ends thereof, and the pin 1 157 and the fixed wheel 1 5 8 limit the same. Move the 'mounted structure' in the direction of the axis. Further, at the end portion of the reduction gear case 515 on the side of the reduction shaft 156, a gear 〗 65 is integrally provided, and the reduction gear box 515 can be freely rotated - 21 - (18) 1272353. The support of the stroke sensor shaft 1 6 6 is set by the dry 1 6 7 ' is engaged with the above gear 1 65. The stroke sensor shaft 1 66 'is a structure connected to a stroke sensor not shown. 'Because the rotating portion of the second idle gear 1 3 5 constituting a part of the reduction gear mechanism 6 6 detects the drive pulley 58. The stroke of the movable pulley half 63' can improve the maintainability of the drive pulley 58 and improve the stroke detection accuracy. The drive gear 1 3 0, the idle gear 1 3 4 • , the second idle gear 1 3 5 , and the second idle gear 1 3 5 of the reduction gear mechanism 6 6 are self-lubricating. The resin is formed, and the drive gear 130, the idle gear 134, and the slide gear 141 are made of metal. Next, the action of the first embodiment will be described. 'The movable pulley half 63 constituting a part of the drive pulley 58 is connected so as not to be relatively movable in the axial direction and relatively rotatable about the axis. One end portion of the slide gear 1 1 4 that slides in the axial direction of the crankshaft 16 is such that the position in the axial direction and the position around the axis are constant, and the cylindrical threaded shaft 1 is disposed coaxially with the crankshaft 16 The outer circumference of 5 is screwed to the inner circumference of the sliding gear 1 14 , and has an end wall portion 116 a fixed to the threaded shaft 1 15 , and is formed into a bottomed cylindrical shape, and the sliding gear U4 and the threaded shaft are formed. Between the inner circumference of the outer casing 1 16 covered by the screwing portion of the 1 1 5 and the outer circumference of the sliding gear 1 14 , an annular sealing member 124 is interposed. Thus, by using a smaller outer casing 116 In addition, it is possible to prevent the operation of the screwing portion of the slide gear 1 14 and the screw shaft 1 15 from being unsmooth due to the intrusion of the ash, and it is possible to prevent the shifting housing 51 from being enlarged. - 22- (19) 1272353 « . and by the connection of the other end portion of the sliding gear i14 and communicating the annular chamber 1 23 formed in the outer casing 1 16 to the external empty chamber portion 1 25 The hole 1 26 is disposed on the threaded shaft 1 1 5 ' so that the annular chamber 1 23 can be prevented from being rapidly pressurized, and the inner circumference of the outer casing 1 16 and the sliding gear 1 1 4 are not caused by the sharp pressurization ' The sealing function of the outer peripheral sealing member 1 24 is impaired. The position of the shaft direction relative to the crankshaft 16 is set to be '' and coaxially|circumscribing the above-mentioned threaded shaft 1 15 of the crankshaft 16 with respect to the direction of rotation around its axis, which is between the anti-vibration rubber 120 and the shifting Since the inner case 52 of the casing body 51 is positioned between the load received from the slide gear 1 14 , the load along the axial direction of the screw shaft 1 15 does not act as a shockproof rubber 1 2 . In other words, only the load in the rotational direction of the screw shaft 1 15 acts on the anti-vibration rubber 120, so that the life of the anti-vibration rubber 120 can be extended, and the shock-proof support structure of the screw shaft 1 15 can be miniaturized. The reduction gear mechanism 66 is accommodated between the electric motor 65 and the movable pulley/half body 63 of the drive pulley 58 and is at least coaxial with the electric motor 65. The connected drive gear 1 300 and the large gear 1 3 1 and the pinion 1 3 2 meshing with the drive gear 1 3 0 are integrally disposed on the idle gear 1 34 formed by the idle rotation shaft 13 3 The reduction gear chamber 1 46 in which the drive gear 130 and the large gear 1 3 1 are accommodated from the housing chamber 56 in the shift housing 5 1 is formed in the outer casing member 147 and the shift housing 5 Between the reduction gear housings 5 of 1 , the outer casing member 147 is formed by forming a labyrinth passage 1 54 between the large gears 13 1 and forming an opening portion 1 53 through which the pinion gears 13 are inserted. -23- (20) 1272353 type, mounted on the reduction gear box body 5 of the shifting housing body 5 1 , the reduction gear mechanism 6 6 ' can prevent the intrusion into the meshing times with a smaller outer casing member 147 A large number of drive gears 1 3 0 and idle gears 1 3 4 can prevent the shifting housing 5 1 from being enlarged and can The service life of the speed reduction mechanism 66 is increased. The reduction gear box body constituting a part of the shift housing 51 is provided with a bearing housing 1 42 that rotatably supports the end portion of the idle rotation shaft 13 3 and is provided with an outer casing member 1 47. 4 9, 1 50, so the labyrinth passage 1 5 4 can be formed smaller and the sealing performance is improved. As in this embodiment, when both ends of the idle rotation gear 1 3 3 of the idle gear 1 3 4 are rotatably supported in the reduction gear housing 55 and the casing 5 2, when the V-belt type is not provided When the transmission is turned on, the idle gear 1 34 is held by the outer casing member 1 74 on the side of the reduction case 55 to prevent it from coming off, and the assemblability can be improved. The reduction gear mechanism 66 includes a second idle gear 1 3 5 formed by a lubricative resin interposed between the pinion gear 1 3 2 of the metal idle gear 1 3 4 and the sliding gear 1 14 . Lubrication can be simplified in the gear meshing portion of the reduction gear mechanism 66 outside the reduction gear chamber 146, and the lubrication structure can be simplified. In the transmission case body 5 1, the second idle gear 1 3 5 made of resin is disposed on the reduction gear The room has a wide space outside the room, which improves the cooling. 1 is a second embodiment showing a screwing portion of a threaded shaft 1 15 and a gear 1 1 4 which is positioned in the axial direction of 16 and which does not need to be rotated about an axis, is: fixed In the threaded shaft 1] 5, in the dusty gear 55, the middle part can be lifted by the inner shaft assembly gear, and the self-engineering resin will be the crankshaft sliding end wall -24 - 1272353. (21) Π 6a The outer casing 1 16 which is formed in a bottomed cylindrical shape is covered with an annular sealing member 124 interposed between the inner circumference of the outer casing 1 16 and the outer circumference of the sliding gear 1 14 . In order to make the annular chamber 1 2 3 formed in the outer casing 1 16 facing the other end portion of the sliding gear 1 14 , the annular chamber 1 2 3 in the outer casing 1 1 is communicated with the receiving chamber 5 6 in the shifting housing 5 1 . The communication hole 155 connected to the upper portion of the annular chamber 1 2 3 is provided at the end wall portion 1 16a of the outer casing 1 16 and the support plate 1 8 '' at the outer portion of the support plate 1 18 It is a communication hole housing 160 that is fixedly mounted to cover the other end of the communication hole 159 and that opens upward. In the second embodiment, in order to rapidly change the shifting section from the TOP to the LOW side, the movable pulley half 63 is rapidly moved toward the width side of the increased belt groove 64, even if the annular chamber 123 The volume of the chamber is rapidly contracted, and the pressurization of the annular chamber 234 can be suppressed without causing the inner circumference of the outer casing 1 16 and the outer peripheral seal member 1 of the sliding gear 1 14 due to rapid pressurization. The sealing function of 4 can be damaged. Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the invention described in the claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view of a power unit and a rear wheel of a first embodiment. Fig. 2 is a sectional view taken along line 2 - 2 of Fig. 1. Fig. 3 is an enlarged view showing the vicinity of the drive pulley of Fig. 2 in the LOW state. -25- (22) 1272353 Fig. 4 is a side view of the threaded shaft and the support plate viewed from the side of the movable sheave. Fig. 5 is a cross-sectional view corresponding to Fig. 3 in the TOP state. Fig. 6 is a cross-sectional view showing a part of the gear reduction mechanism in an enlarged manner. Fig. 7 is a sectional view taken along line 7-7 of Fig. 6. Fig. 8 is a view of the outer casing member viewed from the same direction as Fig. 7. Fig. 9 is a view of the outer casing member as viewed from the opposite side of Fig. 8. Fig. 10 is a cross-sectional view corresponding to Fig. 3 of the second embodiment. [Main component symbol description] 1 6 : Crankshaft as input shaft 5 1 : Transmission case 5 8 : Drive pulley ® 5 9 : Drive pulley 61 : Output shaft 62 : Fixed pulley half 63 : Movable pulley half 64 : Belt groove 1 1 4 : Sliding gear 1 1 5 : Threaded shaft 1 1 6 : Housing 1 16a : End wall
-26- (23)1272353 1 2 Ο :作爲防震構件的防震橡膠 1 2 3 :環狀室 124 :密封構件 1 2 6、1 5 9 :連通孔 M : V型皮帶式無段變速機-26- (23) 1272353 1 2 Ο : Anti-vibration rubber as anti-vibration member 1 2 3 : Annular chamber 124 : Sealing member 1 2 6、1 5 9 : Connecting hole M : V-belt type stepless speed changer
一 27-One 27-