M443768 五、新型說明： 【新型所屬之技術領域】 尤指一種提升引 本創作係關於一種引擎汽缸頭結構 擎散熱效果與均勻性之引擎汽缸頭結構 【先前技術】 引擎冷卻系統之目的是在避免引擎過熱而損壞，或避 #免卫作效率降低m统可概分為空冷系統油冷系統' 與水冷系統，或者為以上之混合式，空冷系統是藉由空氣 在引擎周圍流動以帶走熱量，油冷系統是潤滑油冷卻器先 冷卻潤滑油進而藉由潤滑油在引擎内部循環以帶走熱量， 水冷系統者則是利用水與冷卻劑在引擎水套内流動以帶走 熱量。 參考圖1〜2。習知引擎汽缸頭主要包括一汽虹頭本體 9〇與一凸輪軸座91。汽缸頭本體9〇環周大致區分有四側， φ依序為：火星塞側90卜排氣側9〇2、鍊條室側903、進氣側 9〇4。火星塞側901凹設有一進風流道9〇6，此進風流道9〇6 深達鍊條室908之腔壁96,而且汽缸頭本體9〇之一燃燒室壁 95相反兩側分別為燃燒室9〇5與前述進風流道9〇6。燃燒室 壁95還插設有一火星塞94。進風流道9〇6並與位於排氣側之 一排風流道907相連通。 凸輪軸座91固定於汽缸頭本體9〇,用以支撐一凸輪軸 92而凸輪軸92—端同軸套設一鍊輪mi。一鍊條932延伸 於鍊條至908 ’且同時掛設於上述鍊輪931以及一曲袖（圖未 M443768 示），用以傳動曲軸動力至凸輪軸92。 進入進風流道906之冷卻空氣流會先冷卻火星塞94、 燃燒室壁95外側表面，然後通往排風流道9〇7，使引擎排氣 侧902溫度也稍獲下降。然而’就現有的結構設計而言’風 流排出面積因界定螺拴鎖附孔911，912之距離及肉厚以及 排氣道（圖未示）肉厚之限制而無法大幅度增加，故不易提 升散熱效果。 對於此種習知引擎汽缸頭也明顯地忽略了對鍊條室 側903之冷部作用’使得鍊條室側9〇3存在高溫累積之潛在 危險。 【新型内容】 本創作之主要目的係在提供一種引擎汽缸頭結構，俾 能使汽缸頭冷卻更為均勻，且避免使用於連通管件之〇型 環因高熱而喪失密封功效。 為達成上述目的，本創作之引擎汽缸頭結構包括一汽 缸頭本體、一凸輪軸座、一閥動凸輪機構、一鍊輪、一鍊 條 〇型環及一連通管。上述汽紅頭本體包括有一火星 塞側與-鍊條室側’其t火星塞側凹設有開放之一進風流 道’鍊條室側界定有一鍊條室。 上述凸輪軸座是固定於汽缸頭本體，閥動凸輪機構之 凸輪軸可轉動地支撐於凸輪軸座。鍊輪同軸套設於凸輪 軸，鍊條掛設於鍊輪，並延伸於鍊條室中。 上述連通管自進風流道穿過鍊條室，包括有—冷卻風 道及位於外表面之-環形套設溝槽。冷卻風道延伸至連通 管之兩末端而分別形成一第一開口及一第二開口，其中第 開口連通進風流道’第二開口連通至汽缸頭本體之外 側’而〇型環配設在環形套設溝槽。 特別地’壞形套設溝槽之外壁面之中心、軸線偏離冷卻 風C之中〜轴線’且環形套設溝槽之中心轴線較冷卻風道 之中心軸線更靠近鍊輪。 藉由上述結構設計，因為環形套設溝槽之外壁面之中 攀心轴線與冷卻風道之令心轴線為不共線，可將環形套設溝 槽之中〜轴線设計為較冷卻風道之中心轴線更靠近鍊輪， 一方面使〇型環更遠離燃燒室、管件與鍊輪 之間距仍適當 保持’另-方面可更增加冷卻風道面積，提升散熱效果。 上述冷郐風道可具有各種截面形狀例如圓形戴面。汽 缸頭本體可於表面形成有一鰭片結構。汽缸頭本體可於表 面形成有一導流結構，係曝露於進風流道，以發揮適當導 引風流之功能。環形套設溝槽之槽口方向可平行或垂直於 • 冷卻風道之中心轴線。 【實施方式】 參考圖3〜5，分別為一較佳實施例之汽缸頭頂視圖以 及不同視角之引擎汽缸頭剖視圖。圖中所示為一機車引擎 之汽缸頭結構，包括有一汽缸頭本體丨丨、一凸輪軸座12、 一閥動凸輪機構20、一鍊輪24、一鍊條25及一連通管％。 汽缸頭本體11之外周大致可區分為··火星塞側u丨、排氣側 5 M443768 112、鍊條室側113、進氣側114。汽缸頭本體11界定有一燃 燒室15與一鍊條室14。本實施例之引擎汽缸頭結構還需配 合一上蓋（圖未示）與汽缸頭本體11相結合，於頂面封閉住 汽缸頭本體11，將閥動凸輪機構2〇、鍊條等零部件罩蓋住， 特稱為分離式汽缸頭。圖中所標示座標X係平行火星塞側 111與鍊條室側113連線’座標Y係平行排氣側與進氣側連 線’座標Z平行汽缸頭本體11之高度方向。 火星塞側111凹設有一進風流道13，此進風流道13係 呈對外開放者’且向内延伸抵達鍊條室14之一側壁14 1。隔 在上述進風流道13與燃燒室15之間的是一燃燒室壁151，燃 燒室壁151連接至鍊條室側壁141。一火星塞30穿透燃燒室 壁151而固定，末端伸入到燃燒室15中。 排氣側112為具有排氣道π 6之琿口之一側，進氣側 114則為具有進氣道115之埠口之一側，鍊條室側113為鍊條 室14所在一側。汽缸頭本體11於外表面形成有幫助引擎散 熱之鰭片結構16。進風流道π並與排風流道17相連通。 汽缸頭本體11於表面還形成有一導流結構丨3 1，導流 結構13 1係曝露於進風流道13，用於使空氣流動更為平順， 避免產生紊流情形》 凸輪軸座12是固定於汽缸頭本體η，由頂面觀察大致 呈四邊形’並具有四螺栓鎖附孔12卜124分佈於四角落之 位置。ώ輪軸座12用以支撐一閥動凸輪機構2〇。詳細而言， 閥動凸輪機構20包括一凸輪軸21以及固設於凸輪轴21上之 二閥動凸輪22,23 ’凸輪軸21透過二軸承27,28而可轉動地 M443768 支撐在ώ輪軸座12,二閥動凸輪22,23用於推抵對應之搖臂 機構（圖未示）’進而使進氣閥與排氣閥（圖未示）產生位移。 一鍊輪24同軸固設於凸輪軸21，其上掛設有一鍊條 25。鍊條25延伸於鍊條室14 ’另一端並掛設在一曲軸上之 鍊輪（圖未示）’藉此將曲軸動力傳遞到閥動凸輪機構2〇β 特別地’連通管26包括有貫通呈圓形截面之一冷卻風 道260 ’冷卻風道260延伸至連通管26兩末端分別形成一第 一開口 261與一第二開口 。連通管26沿平行X座標之方 ® 向貫穿鍊條室14,其第一開口 261連通進風流道13,第二開 口 262連通汽缸頭本體！丨之外側。由圖中觀察可得知連通管 26與鍊條室延伸方向（平行z座標）是大致呈垂直者。 在實務作法上，可先在構成鍊條室之二側壁141，142 各形成一穿孔143,144,然後再以事先做好的連通管26穿過 穿孔143,144 ’最後以螺栓鎖附連通管26於汽缸頭本體^。 當然’連通管26之配置必須以不干涉鍊條25作動為前提， 例如在本實施例中’連通管26是位於鍊條輪廓範圍之内， •如此較為節省所佔空間。連通管26當然也可以是位於鍊條 輪廓範圍之外。 此外，連通管26於外表面形成有二環形套設溝槽 33,34(參考圖6)，其中靠近第二開口 262一側之環形套設溝 槽34槽口方向平行冷卻風道26〇之中心軸線C2，靠近第一 開口 261—側之環形套設溝槽33槽口方向則垂直冷卻風道 260之中心軸線C2。 上述二環形套設溝槽33 34分別用於容設〇型環 M443768 3 1，32，以防止引擎内部腔室之氣體或潤滑油從連通管26 與汽缸頭本體11之間不完美配合處洩漏到外部環境。特別 地，環形套設溝槽33之外壁面331之中心轴線C1(本實施例 中，其亦為環形套設溝槽34之外壁面341之中心軸線）偏離 冷卻風道260之中心軸線C2，相隔一距離δ，且環形套設溝 槽33/34之中心軸線C1較冷卻風道之中心軸線C2更靠近鍊 輪24。 由上述可知，當外部空氣流沿平行X座標之方向從火 星塞側之進風流道13流入，一部分會流往排風流道17(平行 Υ座標）’另一部份則流往連通管26，因此不僅排氣側i i 2 可獲得適當冷卻效果，鍊條室側113同樣也能有降低溫度之 效益’使引擎整體散熱效果更佳、進而提升引擎效能。 另外由圖6可清楚比較出，相較於左方之習知對稱型 連通管’本創作之非對稱型連通管因為環形套設溝槽33之 外壁面331之中心軸線C1與冷卻風道260之中心軸線C2不 共線’使得0型環31能更遠離燃燒室15，解決了因高溫導 致變質之問題；而同時冷卻風道之面積也不需減縮，反而 可能加大，藉此獲致更佳冷卻效果。 上述實施例僅係為了方便說明而舉例而已，本創作所 主張之權利範圍自應以申請專利範圍所述為準，而非僅限 於上述實施例。 【圖式簡單說明】 圖1係習知引擎汽缸頭剖視圖。M443768 V. New type description: [New technology field] Especially an engine cylinder head structure for improving the heat dissipation effect and uniformity of an engine cylinder head structure. [Prior Art] The purpose of the engine cooling system is to avoid If the engine is overheated and damaged, or avoid the # 卫 效率 efficiency reduction, the system can be divided into air cooling system oil cooling system and water cooling system, or the above hybrid, air cooling system is carried by air around the engine to take away heat The oil cooling system is a lubricating oil cooler that first cools the lubricating oil and then circulates inside the engine to remove heat. The water cooling system uses water and coolant to flow in the water jacket of the engine to remove heat. Refer to Figures 1 to 2. The conventional engine cylinder head mainly includes a first steam main body 9 〇 and a cam shaft seat 91. The cylinder head body 9 is roughly divided into four sides, and the φ is sequentially: the spark plug side 90, the exhaust side 9〇2, the chain chamber side 903, and the intake side 9〇4. The spark plug side 901 is recessed with an air inlet passage 9〇6, the inlet air flow passage 9〇6 reaching the cavity wall 96 of the chain chamber 908, and the combustion chamber wall 95 of the cylinder head body 9 is opposite to the combustion chamber 9〇5 and the aforementioned inlet air passage 9〇6. A spark plug 94 is also inserted into the combustion chamber wall 95. The intake passage 9〇6 is in communication with a row of air passages 907 located on the exhaust side. The camshaft seat 91 is fixed to the cylinder head body 9A for supporting a camshaft 92 and the camshaft 92 is coaxially sleeved with a sprocket mi. A chain 932 extends from the chain to 908' and is simultaneously attached to the sprocket 931 and a sleeve (not shown in M443768) for transmitting crankshaft power to the camshaft 92. The cooling air flow entering the air flow passage 906 first cools the spark plug 94, the outer surface of the combustion chamber wall 95, and then leads to the exhaust flow passage 9〇7, so that the temperature of the engine exhaust side 902 is also slightly lowered. However, in terms of the existing structural design, the airflow discharge area cannot be greatly increased due to the limitation of the distance and the thickness of the snail lock holes 911, 912 and the thickness of the exhaust passage (not shown), so it is difficult to increase. heat radiation. For such a conventional engine cylinder head, the potential for the cold portion of the chain chamber side 903 is also neglected so that the chain chamber side 9〇3 has a high temperature accumulation. [New content] The main purpose of this creation is to provide an engine cylinder head structure that can make the cylinder head cooling more uniform and avoid the loss of sealing effect due to high heat in the 〇-type ring of the connecting pipe. In order to achieve the above object, the engine cylinder head structure of the present invention comprises a cylinder head body, a camshaft seat, a valve cam mechanism, a sprocket, a chain 〇 ring and a connecting pipe. The steam red head body includes a spark plug side and a chain chamber side 'the t spark plug side recess is provided with an open air inlet flow passage'. The chain chamber side defines a chain chamber. The camshaft seat is fixed to the cylinder head body, and the camshaft of the valve cam mechanism is rotatably supported by the camshaft seat. The sprocket is coaxially sleeved on the camshaft, and the chain is hung on the sprocket and extends in the chain chamber. The connecting pipe passes through the chain chamber from the air inlet passage, and includes a cooling air duct and an annular sleeve groove on the outer surface. The cooling air duct extends to both ends of the communication tube to form a first opening and a second opening, wherein the first opening communicates with the air flow passage 'the second opening communicates with the outer side of the cylinder head body' and the 〇-shaped ring is disposed in the ring shape Set the groove. Specifically, the center of the wall outside the groove of the bad groove is offset from the axis θ of the cooling air C and the central axis of the annular groove is closer to the sprocket than the central axis of the cooling damper. With the above structural design, since the axis of the core of the outer wall of the annular sleeve is not collinear with the axis of the cooling air duct, the axis of the annular sleeve can be designed as Compared with the central axis of the cooling air duct, it is closer to the sprocket. On the one hand, the 〇-shaped ring is further away from the combustion chamber, and the distance between the pipe and the sprocket is still properly maintained, and the cooling air passage area is increased to improve the heat dissipation effect. The above-mentioned cold chimney may have various cross-sectional shapes such as circular wear. The cylinder head body may have a fin structure formed on the surface. The cylinder head body can be formed with a flow guiding structure on the surface to be exposed to the air inlet passage to function as a proper guiding air flow. The direction of the notch of the annular sleeve groove may be parallel or perpendicular to the central axis of the cooling duct. [Embodiment] Referring to Figures 3 to 5, there are respectively a top view of a cylinder head of a preferred embodiment and a cross-sectional view of an engine cylinder head of different viewing angles. The figure shows a cylinder head structure of a locomotive engine comprising a cylinder head body 丨丨, a camshaft seat 12, a valve cam mechanism 20, a sprocket 24, a chain 25 and a connecting pipe %. The outer circumference of the cylinder head body 11 can be roughly divided into a Mars plug side u丨, an exhaust side 5 M443768 112, a chain chamber side 113, and an intake side 114. The cylinder head body 11 defines a combustion chamber 15 and a chain chamber 14. The engine cylinder head structure of the embodiment also needs to be combined with an upper cover (not shown) and the cylinder head body 11 to close the cylinder head body 11 on the top surface, and cover the valve cam mechanism 2, the chain and the like. Live, especially known as the split cylinder head. The coordinate X shown in the figure is a parallel line between the parallel spark plug side 111 and the chain chamber side 113. The coordinate Y is parallel to the exhaust side and the intake side line 'the coordinate Z is parallel to the cylinder head body 11 in the height direction. The spark plug side 111 is recessed with an air inlet passage 13 which is open to the outside and extends inwardly to a side wall 14 1 of the chain chamber 14. Between the air inlet passage 13 and the combustion chamber 15 is a combustion chamber wall 151, and the combustion chamber wall 151 is connected to the chain chamber side wall 141. A spark plug 30 is fixed through the wall 151 of the combustion chamber, and the end projects into the combustion chamber 15. The exhaust side 112 is on one side of the port having the exhaust passage π 6, the intake side 114 is on the side of the port having the intake port 115, and the chain chamber side 113 is on the side of the chain chamber 14. The cylinder head body 11 is formed with a fin structure 16 on the outer surface that helps the engine to dissipate heat. The intake passage π is in communication with the exhaust passage 17. The cylinder head body 11 is further formed with a flow guiding structure 丨3 1 on the surface, and the guiding structure 13 1 is exposed to the air inlet flow passage 13 for smoothing the air flow to avoid turbulence. The camshaft seat 12 is fixed. The cylinder head body η has a substantially quadrangular shape as viewed from the top surface and has four bolt-locking holes 12 and 124 distributed at four corners. The wheel axle seat 12 is for supporting a valve cam mechanism 2〇. In detail, the valve cam mechanism 20 includes a cam shaft 21 and two valve cams 22 fixed to the cam shaft 21, 23' the camshaft 21 is rotatably supported by the two bearings 27, 28 at the MWD wheel bracket. 12, the two valve moving cams 22, 23 are used to push the corresponding rocker arm mechanism (not shown) to further displace the intake valve and the exhaust valve (not shown). A sprocket 24 is coaxially fixed to the camshaft 21, and a chain 25 is hung thereon. The chain 25 extends at the other end of the chain chamber 14' and hangs a sprocket (not shown) on a crankshaft to thereby transmit the crankshaft power to the valve cam mechanism 2〇β, particularly the communication tube 26 includes a through-flow One of the circular sections, the cooling duct 260', the cooling duct 260 extends to the ends of the connecting tube 26 to form a first opening 261 and a second opening, respectively. The communication pipe 26 runs through the chain chamber 14 along the parallel X coordinate, the first opening 261 communicates with the air flow passage 13, and the second opening 262 communicates with the cylinder head body! Outside the 丨. As can be seen from the figure, the connecting pipe 26 and the chain chamber extending direction (parallel z coordinate) are substantially vertical. In practice, a perforation 143, 144 may be formed in each of the two side walls 141, 142 constituting the chain chamber, and then the through-hole 143, 144 ' is finally passed through the communication tube 26 which is prepared in advance, and the communication tube 26 is finally bolted to the cylinder head body. ^. Of course, the configuration of the communication tube 26 must be performed without interfering with the chain 25, for example, in the present embodiment, the "communication tube 26 is located within the outline of the chain," so that the space is saved. The connecting tube 26 can of course also be located outside the outline of the chain. In addition, the connecting tube 26 is formed with two annular sleeve grooves 33, 34 (refer to FIG. 6) on the outer surface, wherein the annular sleeve groove 34 adjacent to the second opening 262 side is parallel to the cooling air passage 26 The central axis C2, adjacent to the first opening 261 - the side of the annular sleeve groove 33, the direction of the slot is perpendicular to the central axis C2 of the air duct 260. The two annular sleeve grooves 33 34 are respectively used for accommodating the ring type ring M443768 3 1,32 to prevent the gas or lubricating oil in the engine internal chamber from leaking from the imperfect fit between the communication pipe 26 and the cylinder head body 11. To the external environment. In particular, the central axis C1 of the outer wall surface 331 of the annular sleeve groove 33 (which is also the central axis of the outer wall surface 341 of the annular sleeve groove 34 in this embodiment) is offset from the central axis C2 of the cooling air duct 260. A distance δ is separated, and the central axis C1 of the annular sleeve groove 33/34 is closer to the sprocket 24 than the central axis C2 of the cooling air passage. As can be seen from the above, when the external air flow flows in the direction of the parallel X coordinate from the air inlet passage 13 on the spark plug side, a part flows to the exhaust flow passage 17 (parallel Υ coordinate) and the other portion flows to the communication pipe 26, Therefore, not only the exhaust side ii 2 can obtain an appropriate cooling effect, but the chain chamber side 113 can also have the effect of lowering the temperature, which makes the overall heat dissipation effect of the engine better, thereby improving the engine performance. In addition, it can be clearly seen from FIG. 6 that the asymmetric communication tube of the present invention is a central axis C1 and a cooling air duct 260 of the outer wall surface 331 of the annular groove 13 as compared with the conventional symmetric communication tube of the left side. The central axis C2 is not collinear, so that the 0-ring 31 can be further away from the combustion chamber 15, solving the problem of deterioration due to high temperature; at the same time, the area of the cooling air passage does not need to be reduced, but may be increased, thereby obtaining more Good cooling effect. The above-described embodiments are merely examples for convenience of description, and the scope of the claims is intended to be based on the scope of the patent application, and is not limited to the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view of a conventional engine cylinder head.