1239308 (1) 玖、發明說明 【發明所屬的技術領域】 本發明是關於機車之鏈條箱構造，在以後端部支承後 輪的車軸的搖臂，安裝從上下夾著該搖臂的上部及下部箱 體，相互連結上部及下部箱體的後端部。 【先前技術】 在搖臂安裝從其上下夾著搖臂的上部箱體及下部箱體 所構成的機車用鍵條相構造’例如在下述的專利文獻1中 習知的構造。 【專利文獻1】 日本特開平9 — 263 27 8號公報 【發明內容】 〔發明欲解決的課題〕 上述習知的鏈條箱構造，是作成全體性地覆蓋用來將 來自於動力單元的旋轉動力傳達到後輪的鏈條，將該上部 及下部箱體安裝於搖臂，構成了所謂的全罩式鏈條箱，上 部及下部箱體的後端連結部，是配置在，通過後輪的車軸 的軸線而朝向搖臂的長軸方向延伸的搖臂中心線的延長處 。也就是說，上部箱體的後端部，是形成爲朝下方繞過搖 臂的後端部，欠缺輕快感。 本發明，鑑於這種情形，其目的要作成一種機車用鏈 條箱構造，是作成全體性地覆蓋鏈條，來將上部及下部箱 -5- (3) 1239308 以下根據附圖所示的本發明的一實施例來說明本發明 的實施方式。 第1圖〜第4圖是顯示本發明的一實施例，第i圖是 機車的側面圖，第2圖是鏈條箱的放大側面圖，第3圖是 第2圖的3 — 3線放大剖面圖，第4圖是第2圖的4 一 4線 放大剖面圖。 首先在第1圖中，該機車的車體框架5，是具備有： 可轉向地支承前叉9的頭管6、從該頭管6朝後下方延伸 的主框架7、以及連接設置於主框架7的後部且朝後上方 延伸的左右一對的後框架8. ·，在上述前叉9的下端軸 支承著前輪W F ’在前叉9的上部連結著桿狀的轉向車把 10，在前叉9，支承著用來覆蓋前輪WF的上方的前擋泥 板1 1 〇 在主框架7的中間部兩側面分別固定安裝著懸架板 1 2 ·.，在主框架7的後部兩側面固定安裝著樞支板i 3 。在主框架7的下方，是配置有將缸體軸線稍微作成朝向 前上方的引擎E，該引擎E，是以上述懸架板12 ··及樞 支板1 3支承而被懸架於車體框架5。 在上述樞支板13，是可上下擺動地支承著後叉14的 前端部，在後叉1 4的後端部是支承著後輪w R的車軸1 5 。在車體框架5的後框架8 ··及後叉14之間是設置有 後避震器1 6。 在後輪WR的上方的後框架8 · ·，是支承著：油箱 1 7、以及配置在該油箱1 7的前方的置物箱1 8，油箱1 7 (4) 1239308 及上述油箱1 7的上方，是以例如雙人乘坐型的乘車用座 墊1 9可開閉地覆蓋著。 在車體框架5，是安裝著用來覆蓋：該車體框架5、 上述引擎E的一部分、油箱1 7及置物箱1 8等的合成樹脂 製的車體外殼20，該車體外殼20，是由：配置於主框架 7的左右兩側的則側外殼2 1 · ·、用來從則方覆盡馬駿者 的腳部而連接於兩前側外殼2 1 ··的前部的腿部護罩22 • ·、用來從前方覆蓋頭管6而連接於兩腿部護罩22 · •的最前部外殻23、從後方側覆蓋頭管6且從上方覆蓋 主框架7而與最前部外殻23相連的主框架上外殼24、與 上述兩前側外殻2 1 ··的下部相連的下外殼25 ··、以 及從兩側覆蓋油箱1 7及置物箱1 8的後側外殼26所構成 〇 上述乘車用座墊1 9，是作成可開閉地配置在後側外 殼2 6的上部，以致能對置物箱1 8進行物品的收容及取出 ，且可對油箱1 8進行供油，用來覆蓋後輪WR的後部上 方的後擋泥板2 7是連接設置於後側外殼2 6。 上述引擎E，是與變速器Μ —起構成了動力單元 Ρ，變速器Μ的輸出會經由鏈條2 8而被傳達到後輪WR。 也就是說，在固定於變速器Μ的輸出軸29的驅動鏈輪30 、與安裝於後輪WR的從動鏈輪3 1 ’是繞掛著循環式的 鏈條2 8。 合倂參照第2圖及第3圖，後叉14，是具備有：形 成爲橫剖面是矩形筒狀且配置在後輪WR的左右兩側的一 (5) 1239308 對搖臂1 4a ·.，在車體框架5的樞支板1 3，是經由水平 的樞軸32而可上下擺動地支承著後叉14的前端部。 後輪WR的輪轂3 3，是經由左右的一對滾珠軸承3 4 • •而可自由旋轉地被支承在車軸1 5，在兩滾珠軸承3 4 • •的內輪之間，是中介安裝著圍繞車軸1 5的圓筒狀的 內側輪軸環3 5。 在輪轂3 3的左端部，是經由緩衝橡膠3 7來連結著鏈 輪座36，在該鏈輪座36是藉由複數的螺栓38· ·及螺母 3 9 .·鎖裝著上述從動鏈輪3 1。而鏈輪座3 6，是使其中 一端的內端抵接於上述兩滾珠軸承3 4 ··中的左側的滾 珠軸承3 4的內輪外端，而經由滾珠軸承4 1可自由旋轉地 被支承於圍繞車軸1 5的圓筒狀的外側輪軸環40。 在左側的搖臂1 4a，在對應於上述鏈輪座3 6的部分 的內側外面部，是焊接著具有由該搖臂1 4a朝上下伸出的 箱體安裝部42a、42b的後部安裝板42，在該後部安裝板 42與上述滾珠軸承4 1的內輪外端之間，中介安裝著圍繞 上述外側輪軸環40的圓筒狀的襯套44，在上述滾珠軸承 41的外側，在鏈輪座36及襯套44之間，是中介安裝著 環狀的密封構件45。藉此，將後輪WR的輪轂33的左端 部及左側的搖臂1 4a之間的間隔設定成爲一定，來防止塵 埃及水由左側侵入到上述輪轂3 3側。 另一方面，將右側的搖臂及上述輪轂3 3的右端部之 間的間隔設定成爲一定，來防止塵埃及水由右側侵入到上 述輪轂3 3側。 (6) 1239308 在左側的搖臂1 4a的後端部的左右兩側及上述後部安 裝板4 3 ’分別設置有前後方向較長的長孔部* 6、4 6、4 7 ’在右側的搖臂的後端部的左右兩側，也分別設置有與上 述長孔部46 ··同樣的長孔（沒有圖示）。在左側的搖 臂14a及上述後部安裝板43的長孔部46、46、47，是可 朝前後方向移動地插通著車軸1 5的左端部、及圍繞於車 軸1 5的左端部的外側輪軸環4 〇 ·.，在右側的搖臂，是 可朝前後方向移動地插穿著車軸1 5的右端部、以及圍繞 車軸1 5的右端部的外側輪軸環。 在由兩搖臂1 4 a ··的後端部起的上述外側輪軸環4 0 • •的突出部，是分別螺合著螺母4 8 · ·，藉由在與兩 搖臂1 4a ·.的後端部外側面之間夾著墊片49 ·.然後鎖 裝上述螺母48· ·，將沿著前後方向也就是搖臂14a. · 的長軸方向的車軸1 5的位置定位在一定的位置。 另一方面，在車軸15的左端部’是一體形成有抵接 、卡合於左側的外側輪軸環4 0的外端的大頭部1 5 a ’雖 然沒有圖示，在車軸1 5的右端部是螺合著與右側的外側 輪軸環的外端抵接、卡合的螺母’藉由鎖裝該螺母’讓車 軸1 5被支承在兩搖臂1 4 a ··的後端部之間。 並且，在兩搖臂1 4 a · •內，在上述外側輪軸環4 0 · •，是固定安裝著可滑動於搖臂l4a· ·內的滑塊5〇· · ，前端部連結在該滑塊50 ··的螺栓5 1 · •的後端部’ 是可朝軸方向移動地貫穿各搖臂1 4a · •的後端壁部’在 由搖臂1 4a ··的後端壁部起的螺栓5 1 ··的突出部’是 -10- (7) 1239308 分別螺合著一對螺母52、53。在放鬆上述螺母48 · •的 狀態，藉由放鬆上述螺母5 2、5 3，可以調節車軸1 5的前 後方向位置而可以調節鏈條28的張力。 合倂參照第4圖，在後叉1 4的左側的搖臂14 a ’是 安裝著從上下夾住該搖臂14a的上部及下部箱體54、55 〇 上部箱體5 4，是把以薄鋼板沖壓成形的表板5 6及背 板5 7接合，作成具有朝下方開口的略U字型的橫剖面形 狀，下部箱體5 5，是把以薄鋼板沖壓成形的表板5 8及背 板5 9接合，作成具有朝上方開口的略U字型的橫剖面形 狀 爲了安裝上部及下部箱體5 4、5 5，在對應於上述鏈 輪座3 6的部分，在搖臂1 4a的內側外面部焊接著上述後 部安裝板42，並且在搖臂1 4a的靠近前端的部分的內側 外面部，是焊接著具有從該搖臂1 4a朝上下伸出的箱體安 裝部 43a、43b。 在後部安裝板42的箱體安裝部42a、42b，是固定安 裝著焊接螺母6 1、6 2，是藉由將插穿於上部箱體5 4的表 板5 6的後側下部的螺栓6 3螺合鎖裝於上述焊接螺母6 1 ’上述表板5 6的後側下部’會以從外側覆蓋箱體安裝部 42a的方式，被安裝於該箱體安裝部42a。藉由將插穿於 下部箱體5 5的表板5 8的後側上部的螺栓6 4螺合鎖裝於 上述焊接螺母62，上述表板5 8的後側上部，會以從外側 覆蓋箱體安裝部42b的方式，被安裝於該箱體安裝部42b -11 - (8) 1239308 藉由將插穿於上部箱體54的表板56的後側下部的螺 栓6 5螺合鎖裝於固定安裝在前部安裝板4 3的箱體安裝部 4 3 a的焊接螺母（沒有圖示），上述表板5 6的前側下部 ，會以從外側覆蓋箱體安裝部4 3 a的方式，被安裝於該箱 體安裝部4 3 a。藉由將插穿於下部箱體5 5的表板5 8的後 側上部的螺栓6 6螺合鎖裝於固定安裝在前部安裝板4 3的 箱體安裝部43b的焊接螺母（沒有圖示），上述表板58 的前側上部，會以從外側覆蓋箱體安裝部4 3 b的方式，被 安裝於該箱體安裝部43b。 在較上述後部安裝板42更前方，在上述搖臂14a的 後部上面部，是焊接著朝上方開口的略U字型的托架67 ，在該托架67的內側是固定安裝著焊接螺母68。並且， 在托架67內是插入著後避震器16的下端部，藉由將插通 於托架6 7及後避震器1 6的下端部的螺栓6 9螺合鎖裝於 上述焊接螺母6 8，來將後避震器1 6的下端部連結於搖臂 1 4 a的後部。 上部及下部箱體5 4、5 5的後端部，例如是將下部箱 體5 4的表板5 8的後端部重疊於上部箱體5 4的表板5 6的 內側，並且將下部箱體5 4的背板5 9的後端部重疊在上部 箱體5 4的背板5 7的內側，而相互連結，上部及下部箱體 5 4、5 5的後端連結部7 0，是偏置配置到，通過後輪WR 的車軸1 5的軸線而延伸於搖臂1 4a的長軸方向的搖臂中 心線C的更上方處。 -12- (9) 1239308 並且，上部及下部箱體5 4、5 5的後端連結部7 〇 端，是配置在較搖臂1 4a的後端更前方處，上述後端 部70，是配置成隨著朝向後方而成爲上方的位置。 上部及下部箱體54、55，是藉由塗裝或電鍍等 著色，將顏色區分成讓上部及下部箱體5 4、5 5之間 暗差異很大，在該實施例中，上部箱體54側是將顏 分成較下部箱體5 5側更明亮的顏色。例如上部箱體 色爲銀色時，下部箱體5 5則著色成黑色。而搖臂L· 著色成較下部箱體5 5更明亮的顏色，例如著色成銀€ 第1圖及第2圖，爲了顯示下部箱體55是暗色 在下部箱體5 5上實施描點處理，該描點處理並不是 在下部箱體5 5上進行。 接下來針對該實施例的作用來加以說明，安裝於 14的搖臂14a而從上下夾著搖臂14a的上部及下部 54、55的後端連結部70，是偏置配置到，通過後輪 的車軸1 5的軸線而延伸於搖臂1 4 a的長軸方向的搖 心線C的更上方處，所以當從側邊來看由上部及下部 5 4、5 5所構成的鏈條箱全體時，會呈現鏈條箱的後 後上方揚起的外觀，可以得到與半罩式鏈條箱同樣的 感的外觀。 上部及下部箱體54、55的後端連結部70的前端 配置在較搖臂1 4a的後端更前方處，所以下部箱體ί 後端是形成爲朝上方繞過搖臂1 4a的後端部，可更提 快感。 的前 :連結 方式 的明 色區 54著 4a也 1 0 ，而 實際 後叉 箱體 WR 臂中 箱體 部朝 輕快 ，是 ;5的 昇輕 -13- (10) 12393081239308 (1) 发明 Description of the invention [Technical field to which the invention belongs] The present invention relates to a chain case structure of a locomotive. A swing arm that supports a rear axle of a rear wheel at a rear end portion is mounted on an upper portion and a lower portion of the swing arm that sandwich the swing arm The box connects the rear end portions of the upper and lower boxes to each other. [Prior Art] A locomotive key bar structure constructed by mounting an upper case and a lower case sandwiching the swing arm from above and below the swing arm is, for example, a structure known in Patent Document 1 described below. [Patent Document 1] Japanese Patent Application Laid-Open No. 9 — 263 27 8 [Summary of the Invention] [Problems to be Solved by the Invention] The conventional chain box structure is constructed so as to cover the entire rotation power from the power unit. The upper and lower cases are attached to the swing arm by the chain that is transmitted to the rear wheels to form a so-called full-cover chain case. The rear end joints of the upper and lower cases are arranged at The extension of the center line of the rocker arm extending in the direction of the long axis of the rocker arm along the axis. That is, the rear end portion of the upper case is formed so as to bypass the rear end portion of the swing arm downward, and lacks lightness. In view of this situation, the present invention aims to make a locomotive chain box structure that covers the chain as a whole to cover the upper and lower boxes -5- (3) 1239308. An example is used to explain the embodiment of the present invention. 1 to 4 are diagrams showing an embodiment of the present invention, FIG. I is a side view of a locomotive, FIG. 2 is an enlarged side view of a chain case, and FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2. FIG. 4 is an enlarged cross-sectional view taken along the line 4-4 in FIG. 2. First, in the first figure, the body frame 5 of the locomotive is provided with a head pipe 6 that can steerably support the front fork 9, a main frame 7 that extends from the head pipe 6 to the lower back, and is connected to the main body. A pair of left and right rear frames 8 extending rearward and rearward of the frame 7. The front wheel 9 is pivotally supported at the lower end of the front fork 9. A rod-shaped steering handlebar 10 is connected to the upper portion of the front fork 9. The front fork 9 supports front fenders 1 1 10 for covering the front wheels WF. Suspension plates 1 2 are fixedly mounted on both sides of the middle portion of the main frame 7, and are fixed on both sides of the rear portion of the main frame 7. A pivot support plate i 3 is installed. Below the main frame 7, an engine E having a cylinder axis slightly facing forward is disposed. The engine E is supported by the suspension plate 12 ... and the pivot plate 13 and is suspended from the vehicle body frame 5. . The pivot plate 13 supports a front end portion of the rear fork 14 swingably up and down, and a rear end portion of the rear fork 14 is an axle 15 supporting a rear wheel w R. A rear suspension 16 is provided between the rear frame 8 of the vehicle body frame 5 and the rear fork 14. The rear frame 8 above the rear wheel WR is supported by a fuel tank 17 and a storage box 18 disposed in front of the fuel tank 17 and a fuel tank 17 (4) 1239308 and above the fuel tank 17 For example, it is covered with a seat cushion 19 for a two-seater type that can be opened and closed. The body frame 5 is mounted with a synthetic resin body shell 20 for covering the body frame 5, a part of the engine E, the fuel tank 17 and the storage box 18, and the like. It is composed of: the side shells 2 1 ·· arranged on the left and right sides of the main frame 7, and the legs of the front part of the two front side shells 2 1 ·· for covering the horse's feet from the side. Shroud 22 ••, the frontmost case 23 for covering the head pipe 6 from the front and connected to the two leg shrouds 22, • the head pipe 6 from the rear side and the main frame 7 from the top, and the front part The main frame upper casing 24 connected to the casing 23, the lower casing 25 connected to the lower portions of the two front side casings 2 1 ..., and the rear casing 26 covering the fuel tank 17 and the storage box 18 from both sides Structure 〇 The above-mentioned passenger seat cushion 19 is configured to be openable and closable and arranged on the upper part of the rear case 26 so that the storage box 18 can receive and remove articles, and the fuel tank 18 can be oiled. The rear fender 27 for covering the upper part of the rear part of the rear wheel WR is connected to the rear case 26. The above engine E constitutes a power unit P together with the transmission M, and the output of the transmission M is transmitted to the rear wheel WR via the chain 28. That is, the drive sprocket 30 fixed to the output shaft 29 of the transmission M and the driven sprocket 3 1 ′ attached to the rear wheel WR are looped chains 28. Combined with reference to Figures 2 and 3, the rear fork 14 is provided with a (5) 1239308 pair of rocker arms 1 4a formed in a rectangular cylindrical shape in cross section and disposed on the left and right sides of the rear wheel WR. The pivot plate 13 of the vehicle body frame 5 supports a front end portion of the rear fork 14 so as to be swingable up and down via a horizontal pivot shaft 32. The hub 3 3 of the rear wheel WR is supported rotatably on the axle 15 via a pair of left and right ball bearings 3 4 •, and is interposed between the inner wheels of the two ball bearings 3 4 • • A cylindrical inner wheel collar 3 5 surrounding the axle 15. At the left end of the hub 33, a sprocket seat 36 is connected via a cushion rubber 37, and the sprocket seat 36 is locked with a plurality of bolts 38 ... and nuts 3 9 ... Round 3 1. The sprocket seat 36 is such that the inner end of one end abuts the outer end of the inner wheel of the left ball bearing 3 4 of the two ball bearings 3 4 ··, and is freely rotatable via the ball bearing 41. It is supported by a cylindrical outer wheel collar 40 that surrounds the axle 15. A rocker arm 14a on the left side is a rear mounting plate welded with a box mounting portion 42a, 42b having a rocker arm 14a projecting upwards and downwards on the inner side outer portion of the portion corresponding to the sprocket seat 36. 42. Between the rear mounting plate 42 and the outer end of the inner ring of the ball bearing 41, a cylindrical bush 44 surrounding the outer wheel collar 40 is interposed. Outside the ball bearing 41, a chain A ring-shaped sealing member 45 is interposed between the wheel seat 36 and the bushing 44. Thereby, the interval between the left end portion of the hub 33 of the rear wheel WR and the left rocker arm 14a is set to be constant to prevent dust and water from entering the hub 33 side from the left side. On the other hand, the interval between the right rocker arm and the right end of the hub 33 is set constant to prevent dust and water from entering the hub 33 from the right side. (6) 1239308 On the left and right sides of the rear end of the swing arm 14a on the left side and the rear mounting plate 4 3 ', there are long holes in the front-rear direction * 6, 4, 6, 4 7' on the right side. The left and right sides of the rear end portion of the swing arm are also provided with long holes (not shown) similar to the long hole portions 46.... The left rocker arm 14a and the long hole portions 46, 46, and 47 of the rear mounting plate 43 are inserted through the left end portion of the axle 15 and the outer side surrounding the left end portion of the axle 15 so as to be movable in the front-rear direction. The wheel collar 4 〇 .. The rocker arm on the right side is inserted into the right end of the axle 15 and the outer wheel collar surrounding the right end of the axle 15 so as to be movable in the front-rear direction. The protruding parts of the outer wheel collar 4 0 • from the rear end portions of the two rocker arms 1 4 a ·· are screwed to the nuts 4 8 ··, respectively, by the two rocker arms 1 4a ·. A gasket 49 is sandwiched between the outer surfaces of the rear end portion of the rear end, and then the above-mentioned nut 48 · is locked, and the position of the axle 15 in the longitudinal direction of the rocker arm 14a in the front-rear direction is fixed at a certain position. position. On the other hand, at the left end portion of the axle 15, a large head portion 1 5 a 'abutting and engaging with the outer end of the outer wheel collar 40 on the left side is integrally formed. Although not shown, at the right end portion of the axle 15 The nut 15 that is screwed into contact with the outer end of the outer wheel collar on the right side and is engaged with the shaft 15 is supported between the rear ends of the two rocker arms 1 4 a ·· by locking the nut. In the two rocker arms 1 4 a · • and the outer wheel collar 4 0 · •, a slider 5 0 · · that can be slid into the rocker arm 14 a · · is fixedly mounted, and the front end portion is connected to the slide. The rear end of the block 50 ·· bolt 5 1 · • is a shaft rearwardly penetrating through each of the rocker arms 1 4a · • The rear end wall portion starts from the rear wall of the rocker arm 1 4a · · The protruding portion of the bolt 5 1 ·· is -10- (7) 1239308, and a pair of nuts 52 and 53 are screwed into each of them. In a state where the nuts 48 · • are loosened, by loosening the nuts 5 2, 5 3, the front-rear position of the axle 15 can be adjusted and the tension of the chain 28 can be adjusted. Referring to FIG. 4, the swing arm 14 a ′ on the left side of the rear fork 14 is attached to the upper and lower cases 54 and 55 that hold the swing arm 14 a from above and below. The sheet metal plate 5 6 and the back plate 57 are formed by pressing a thin steel plate, and are formed into a U-shaped cross-sectional shape that opens downward. The lower case 5 5 is a sheet metal 5 8 and The back plate 5 9 is joined to form a slightly U-shaped cross-sectional shape that opens upward. In order to mount the upper and lower cases 5 4 and 5 5, the portion corresponding to the sprocket seat 36 described above is attached to the swing arm 1 4a. The above-mentioned rear mounting plate 42 is welded to the inner outer surface portion, and box mounting portions 43a, 43b having the rocker arm 14a near the front end portion are welded to have the box mounting portions 43a, 43b projecting upward and downward from the rocker arm 14a. . The box mounting portions 42a and 42b of the rear mounting plate 42 are fixedly mounted with the welding nuts 6 1 and 6 2, and are bolts 6 inserted through the lower portion of the rear side of the watch plate 5 6 inserted into the upper box 5 4. The 3 screw lock is mounted on the welding nut 6 1 'the lower part of the rear side of the watch plate 5 6' and is mounted on the box mounting portion 42a so as to cover the box mounting portion 42a from the outside. The bolts 64 inserted into the upper portion of the rear side of the lower plate 5 5 of the lower case 5 5 are screw-locked to the welding nut 62. The upper portion of the rear side of the upper plate 5 8 covers the box from the outside. The body mounting portion 42b is mounted to the box mounting portion 42b. -11-(8) 1239308 is bolted to the lower portion of the rear side of the face plate 56 of the upper case 54 by screwing. Welding nuts (not shown) fixed to the box mounting portion 4 3 a of the front mounting plate 4 3. The lower portion of the front side of the watch plate 56 will cover the box mounting portion 4 3 a from the outside. It is attached to this case mounting part 4 3 a. The bolts 6 6 inserted into the upper part of the rear side of the lower plate 5 5 of the lower case 5 8 are screw-locked to the welding nuts (not shown) fixed to the case mounting portion 43 b of the front mounting plate 4 3. (Shown), the upper part of the front side of the watch plate 58 is mounted on the box mounting portion 43 b so as to cover the box mounting portion 4 3 b from the outside. A slightly U-shaped bracket 67 is welded to the upper surface of the rear portion of the rocker arm 14a at a position further forward than the rear mounting plate 42. A welding nut 68 is fixedly mounted inside the bracket 67. . The lower end portion of the rear shock absorber 16 is inserted into the bracket 67, and the bolts 6 9 inserted into the lower end portions of the bracket 67 and the rear shock absorber 16 are screw-locked to the welding. A nut 68 is used to connect the lower end portion of the rear shock absorber 16 to the rear portion of the swing arm 14a. The rear end portions of the upper and lower cases 5 4 and 5 5 are, for example, the rear end portions of the face plate 5 8 of the lower case 5 4 and the inside of the face plate 5 6 of the upper case 5 4, and The rear end portion of the back plate 5 9 of the case 5 4 is overlapped with the inner side of the back plate 5 7 of the upper case 5 4 and is connected to each other. The rear end connection portions 70 of the upper and lower cases 5 4 and 5 5 are connected to each other. It is arranged so as to be offset above the center line C of the rocker arm extending in the long axis direction of the rocker arm 14a through the axis of the axle 15 of the rear wheel WR. -12- (9) 1239308 Furthermore, the rear end connecting portions 70 of the upper and lower cases 5 4 and 5 5 are disposed more forward than the rear end of the swing arm 14 a. The rear end portion 70 is It is arrange | positioned so that it may become an upper position as it goes to the back. The upper and lower cases 54 and 55 are colored by painting or electroplating, and the colors are distinguished so that there is a large dark difference between the upper and lower cases 5 4 and 55. In this embodiment, the upper cases On the 54 side, the face is divided into brighter colors than on the lower side of the lower case. For example, when the upper case is silver, the lower case 5 5 is colored black. The rocker L · is colored brighter than the lower case 55, for example, it is colored silver. Figures 1 and 2 show the lower case 55 in order to show that the lower case 55 is dark. This tracing process is not performed on the lower case 55. Next, the function of this embodiment will be described. The rear end connecting portion 70 attached to the rocker arm 14a of 14 and sandwiching the upper and lower portions 54 and 55 of the rocker arm 14a from above and below is disposed offset to the rear wheel and passes through the rear wheel. The axis of the axis 15 extends above the center line C of the long axis of the rocker arm 14a, so when viewed from the side, the entire chain box composed of the upper and lower parts 5 4, 5 5 At the same time, the appearance of the chain box rising rearward, rearward, and upper is presented, and the appearance similar to that of the half-cover type chain box can be obtained. The front ends of the rear end connecting portions 70 of the upper and lower cases 54 and 55 are disposed more forward than the rear ends of the swing arms 14a, so the rear end of the lower case ί is formed to bypass the swing arms 14a upwards. Ends for more pleasure. The front: the light-colored area of the connection method 54 is 4a and 10, but the actual rear fork box WR arm in the box part is light and light; it is 5 liters -13- (10) 1239308
在將上部相體5 4對搖臂1 4 a進行安裝時，將下部箱 體5 5的後端部利用爲導引部則可提高組裝性。並且，上 部及下部箱體54、55的後端部，是將下部箱體54的表板 5 8的後端部重疊於上部箱體5 4的表板5 6的內側，並且 將下部箱體5 4的背板5 9的後端部重疊在上部箱體5 4的 背板5 7的內側，來加以連結，所以在將下部箱體5 5對搖 臂14a進行安裝之後，藉由將上部箱體54的後端部重疊 於下部箱體5 5的後端部，則容易進行上部箱體5 4對搖臂 14a的安裝操作，而能將上部箱體54保持於下部箱體55 ，可更提高上部箱體54對搖臂14a的組裝性。 上部及下部箱體5 4、5 5，是將顏色加以區別，讓相 互間的明暗的差異變大，例如上部箱體5 4側成爲較下部 箱體5 5側更明亮的顏色，藉由區分顏色將彼此的明暗差 異變大，而可得到更具輕快感的外觀。When the upper phase body 5 4 is mounted on the rocker arm 14 a, the rear end of the lower case body 5 5 is used as a guide to improve the assemblability. In addition, the rear end portions of the upper and lower cases 54 and 55 overlap the inner side of the lower case 54 with the rear end portion of the face plate 58 of the lower case 54 on the inside of the face plate 56 of the upper case 54. The rear end of the back panel 5 9 is superimposed on the inside of the back panel 5 7 of the upper case 5 4 to be connected. Therefore, after the lower case 5 5 is mounted on the swing arm 14 a, the upper part is attached by The rear end portion of the box 54 overlaps the rear end portion of the lower box 55, so that the mounting operation of the upper box 54 to the swing arm 14a is easy, and the upper box 54 can be held on the lower box 55. The assemblability of the upper case 54 to the swing arm 14a is further improved. The upper and lower boxes 5 4 and 5 5 are distinguished from each other in color to make the difference between light and dark. For example, the upper box 5 4 side becomes a brighter color than the lower box 5 5 side. The color will increase the difference between light and shade, and you can get a more light look.
以上說明了本發明的實施方式，本發明並不限定於上 述實施方式，只要不脫離本發明的專利範圍，則可進行種 種設計變更。 例如在上述實施例中，雖然上部及下部箱體5 4、5 5 是由薄鋼板構成的，而也可藉由合成樹脂分別形成上部及 下部箱體。在這種情況，上部及下部箱體的著色並不限定 於塗裝方式，藉由使用著色劑、或拉深處理，則可廉價地 實現上部及下部箱體的表面的嶄新表現。 也可以作成讓上部箱體5 4較下部箱體5 5更亮且加上 明暗的對比。 -14- (11) (11)1239308 〔發明效果〕 藉由第1發明，當從側面來看鏈條箱全體時，會呈現 鏈條箱的後部向後上方揚起的外觀，而能夠得到具有輕快 感的外觀。 藉由第2發明，可更提昇輕快感，且當上部箱體對搖 臂進行安裝時，可將下部箱體的後端部利用爲導引部，而 能夠提高組裝性。 藉由第3發明，而可得到更具輕快感的外觀。 【圖式簡單說明】 第1圖是機車的側面圖。 第2圖是鏈條箱的放大側面圖。 第3圖是第2圖的3 — 3線放大剖面圖。 第4圖是第2圖的4 一 4線放大剖面圖。 〔圖號說明〕 14a :搖臂 1 5 :車軸 5 4 :上部箱體 5 5 :下部箱體 7 〇 :後端連結部 C :搖臂中心線 WR :後輪 -15-The embodiments of the present invention have been described above. The present invention is not limited to the above-mentioned embodiments, and various design changes can be made without departing from the patent scope of the present invention. For example, in the above embodiment, although the upper and lower cases 5 4 and 5 5 are made of thin steel plates, the upper and lower cases may be formed by synthetic resin, respectively. In this case, the coloring of the upper and lower cases is not limited to the painting method. By using a coloring agent or a deep drawing treatment, a new expression of the surface of the upper and lower cases can be realized at a low cost. It is also possible to make the upper case 5 4 brighter and add light and dark contrast than the lower case 55. -14- (11) (11) 1239308 [Effects of Invention] According to the first invention, when the entire chain box is viewed from the side, the rear portion of the chain box is raised upward and rearward, and a light-bodied texture can be obtained. Exterior. According to the second invention, the lightness can be further enhanced, and when the swing arm is mounted on the upper case, the rear end portion of the lower case can be used as a guide, which can improve the assemblability. According to the third invention, a lighter appearance can be obtained. [Brief description of the drawings] Fig. 1 is a side view of a locomotive. Fig. 2 is an enlarged side view of the chain case. Fig. 3 is an enlarged cross-sectional view taken along line 3-3 in Fig. 2. Fig. 4 is an enlarged cross-sectional view taken along the line 4-4 in Fig. 2; [Illustration of drawing number] 14a: rocker arm 15: axle 5 4: upper case 5 5: lower case 7 〇: rear connecting part C: rocker centerline WR: rear wheel -15-