200424434 玖、發明說明： 【發明所屬之技術領域】 本發明係關於一種内燃機之汽缸頭，該汽缸頭形成 星塞的插入孔和可以轉動支承開閉進氣閥及排氣閥的 凸輪軸的軸承部。 【先前技術】 這種内燃機之汽缸頭已知如專利文獻1中公開。在 缸頭，火星塞安裝成如下結構，使電極部位於燃燒室 致中心部，以便燃燒室内燃燒均勻而且迅速進行，火 插入的插入孔形成為從侧面看對於汽缸軸線傾斜。而 從側面看可以轉動地支承凸輪軸的一對頭側軸承部半 汽缸頭的、與汽缸頭蓋結合的面上形成開口 ，所述凸 與插入孔相對於汽缸軸線傾斜方向相反的方向上偏心 置。因此，一對頭側軸承部半體與在汽缸頭蓋上形成 對蓋側軸承半體共同構成支承凸輪軸的一對軸承部。 專利文獻1 :日本專利實願昭6 2 - 9 4 0 8 0號（實開昭 6 3 - 2 0 2 7 0 7號）的微型膠片（圖1 )。 【發明内容】 (發明所欲解決之問題） 但是，為了防止火星塞的電極部突出設置的前端暴 高溫的燃燒氣體中過熱，該前端在燃燒室内幾乎不突 或者在僅僅突出一點的情況下，插入火星塞的插入孔 度增大，火星塞中沒有佔據插入孔的空間部分的容積 大，因此，由於燃燒室的容積增加，壓縮比下降，因 312/發明說明書(補件)/93-06/93丨08657 有火 單個 該汽 的大 星塞 且， 體在 輪軸 ->n. δ又 的一 露在 出， 傾斜 變 此内 6 200424434 燃機的輸出降低，或者電極部距離燃燒室位於插入孔 稍後退的位置上，則點火性能下降。因此，希望插入 傾斜度盡可能地小。 一方面，汽缸頭的結合面與汽缸頭蓋的結合面之間 密封構件，因此必須在兩個結合面上確保有用於通過 構件密封兩個結合面的帶狀密封區域。因此’各個軸 如同頭側軸承部半體和頭蓋側軸承部半體構成的上述 技術那樣，兩個結合面在汽缸軸線方向上與凸輪軸重 置上的汽缸頭中，各個軸承部具有用於確保結合面所 的密封性的密封區域，因此向凸輪軸的軸方向伸出。 因此，在上述現有技術中，若想使插入孔的傾斜度 小，因為靠近火星塞的軸承部的伸出部分影響火星塞 安裝在該火星塞的塞蓋，使插入孔傾斜度小，則使火 的傾斜度變小比較難。 而且，一對軸承部中必須受來自進氣閥和排氣閥的 而且穩定支援轉動的凸輪軸。但是，該軸承部在結合 分為兩部分的情況下，為了確保穩定地支承凸輪軸所 的剛性，若增加軸承部的壁厚，由於軸承部向火星塞 進一步伸出，難以使火星塞的傾斜度變小。 本發明鑒於上述問題作出發明，申請專利範圍第1 項之發明，其目的在於，在火星塞設置成傾斜的情況 通過進一步減小其傾斜提高内燃機的輸出和點火性能 且能夠實現内燃機輕量化。而且，申請專利範圍第2 項之發明又以實現汽缸頭小型化為目的，申請專利範 312/發明說明書(補件)/93-06/93108657 内稍 孔的 設置 密封 承部 現有 合位 需要 變 或者 星塞 反力 面上 需要 方向 至3 下， ， 而 、3 圍第 200424434 4項之發明進一步實現如下目的，進一步使安裝燃料喷射 閥的汽缸頭周圍緊湊，同時增加内燃機的輸出。 (解決問題之手段） 申請專利範圍第1項之發明是在結合到汽缸上的内燃機 汽缸頭上形成有：插入火星塞的插入孔，上述火星塞具有 臨近燃燒室的大致中央位置的電極部；第一軸承部和第二 軸承部，可轉動地支承設置有開閉進氣閥和排氣閥的動閥 凸輪的單一凸輪軸；及汽缸頭蓋通過密封構件結合的結合 面，其包含有：支承上述凸輪軸一端的第一軸承部，係位於 俯視為與上述插入孔重合的位置，而且在汽缸軸線方向上 位於上述插入孔與上述結合面之間的位置，同時由上述凸 輪軸的軸方向上的上述汽缸頭的側壁所構成，用以覆蓋上 述端部的整個端面，從上述軸方向上看，上述火星塞或者 安裝於火星塞的塞蓋與上述第一軸承部重合。 由此，由於在汽缸軸線方向上插入孔與結合面之間通過 側壁構成的第一軸承部上沒有結合面，因此不需要設置確 保密封性的密封區域，能夠抑制從軸方向上看向在與第一 軸承部重合位置上設置的火星塞或者塞蓋伸出的量，能夠 減小從側面看插入孔相對於汽缸軸線的傾斜，即火星塞或 者塞蓋的傾斜。而且，第一軸承部不需要在軸承部被分開 情況下為了提高凸輪軸的支承剛性必須提高側壁的厚度。 申請專利範圍第2項之發明是在申請專利範圍第1項的 内燃機汽缸頭中，上述進氣閥和上述排氣閥通過可以分別 擺動支承在一對擺臂軸上的進氣擺臂和排氣擺臂而由上述 8 312/發明說明補件)/93-06/93108657 200424434 動閥凸輪控制開閉，上述一對擺臂軸在上述汽缸軸線方向 上位於上述第一轴承部與上述結合面之間’同時俯視看為 配置於兩侧用以夾上述凸輪軸的轉動中心線’上述一對擺 臂軸的一端支承在由上述側壁構成的一對支承部上’上述 一對支承部位於俯視為夾上述第一軸承部的位置。 由此，在汽缸軸線方向上在第一軸承部和結合面之間通 過側壁構成的一對支承部上支承的一對支承部上，由於沒 有結合面，不需要設置確保密封性的密封區域，抑制一對 支承部向火星塞或者塞蓋的伸出量，從側面看可以減小插 入孔相對於汽缸軸線的傾斜，即可減小火星塞或者塞蓋的 傾斜，因此能夠使兩個擺臂軸接近凸輪軸，縮短兩個凸輪 軸之間的軸間距。 申請專利範圍第3項之發明是在申請專利範圍第1項之 内燃機汽缸頭中，上述進氣閥和上述排氣閥分別藉助於具 有與上述動閥凸輪接觸的輥子的進氣擺臂和排氣擺臂而由 上述動閥凸輪控制開閉，上述第二軸承部支承上述凸輪軸 的另一端，上述動閥凸輪設置在上述第一軸承部和上述第 二軸承部之間，上述第一軸承部和上述第二軸承部的上述 軸方向上的間隔大致等於設置上述動閥凸輪的上述軸方向 上的範圍。 由此，動閥凸輪與擺臂之間的接觸變成滾動接觸，由於 摩擦係數變小，即使動閥凸輪與擺臂之間的接觸壓力增 大，動閥凸輪以及擺臂的耐摩性能也不會降低，因此能夠 減小動閥凸輪在軸方向上的尺寸。而且，分別支承凸輪軸 9 312/發明說明書(補件)/93-06/93108657 200424434 兩個端部的第一和 置的範圍而減小。 申請專利範圍第 内燃機汽缸頭中， 轉動中心線垂直的 喷射閥的安裝孔和 過上述進氣閥開閉 成於上述汽缸蓋上 汽缸軸線方向上比 上述軸方向看位於 由此，在汽缸頭 容積的通氣室影響 軸的轉動中心線位 燃料喷射閥相對於 能夠更加沿著汽缸 料向進氣口的進氣 而且，本說明書 是指凸輪軸的轉動 看，側面看是指從 缸軸線的平面垂直 (發明效果） 根據申請專利範 由於能夠減小插入 燒室容積增大，提 第二軸承部之間的間 4項之發明是在申請 上述汽缸頭的、俯視 方向上的一個側壁上 通氣通路，上述燃料 的進氣孔的進氣管， 的通氣室連通，上述 上述通氣室更靠近上 與上述通氣通路重合 中，不會使燃料噴射 ，能夠設置在上述垂 置上，而且由於從軸 汽缸軸線的傾斜，因 軸線方向，能夠使來 孔喷射，減少喷濺在 和本發明的權利要求 中心線方向，平視是 與平行於含有凸輪軸 的方向看。 圍第1項之發明，具 孔傾斜，因此能夠抑 高/内燃機的輸出，而 隔根據動閥凸輪設 專利範圍第1項之 為與上述凸輪軸的 ，形成有安裝燃料 噴射閥臨近具有通 上述通氣通路與形 燃料喷射閥在上述 述進氣？L ，而且從 的位置上。 閥被通氣通路和大 直方向上靠近凸輪 方向上看能夠減小 此燃料噴射中心線 自燃料噴射閥的燃 排氣口上。 的範圍中，軸方向 指從汽缸軸線方向 的轉動中心線的汽 有以下效果。即， 制由於插入孔使燃 且抑制電極部在插 10 3丨2/發明說明書(補件)/93-06/93108657 200424434 入孔内的後退，提高點火性能。而且’不需要在分割軸承 部等情況下需要提高凸輪軸的支承剛性而增加側壁的厚 度，因此能夠使内燃機輕量化。 根據申請專利範圍第2項之發明，除了能夠實現申請專 利範圍第1項之發明的效果之外，還能夠實現如下效果。 即，雖然火星塞或者塞蓋的傾斜度減小了，但是不會對一 對擺臂軸的支承部影響，而且能夠使兩個擺臂軸靠近凸輪 軸，縮短兩個軸之間的軸間距離，能夠在平視中與轉動中 心線垂直的方向上使汽缸頭小型化。 根據申請專利範圍第3項之發明，除了申請專利範圍第 1項之發明效果之外，還能夠達到如下效果。即，能夠減 小動閥凸輪在軸方向上的尺寸，而且第一和第二軸承部之 間的間隔隨著設置動閥凸輪的範圍而減小，因此能夠同時 縮短凸輪軸的長度，能夠使汽缸頭在軸方向上小型化。 根據申請專利範圍第4項之發明，除了申請專利範圍第 1項之發明效果之外，還能夠達到如下效果。即，在上述 垂直方向上使燃料喷射閥設置得靠近凸輪軸的轉動中心線 上，因此能夠使燃料噴射閥在上述垂直方向上在汽缸頭中 緊湊設置，能夠使汽缸頭周圍緊湊，因此能夠使來自燃料 喷射閥的燃料的喷射中心線進一步沿著汽缸軸線方向喷 射，能夠減少吹向排氣口 ，因此能夠提高内燃機的輸出。 【實施方式】 下面參照圖1〜圖1 2說明本發明的實施形態。200424434 发明 Description of the invention: [Technical field to which the invention belongs] The present invention relates to a cylinder head of an internal combustion engine. The cylinder head forms an insertion hole for a star plug and a bearing portion of a camshaft that can rotatably support opening and closing of an intake valve and an exhaust valve. . [Prior Art] A cylinder head of such an internal combustion engine is known as disclosed in Patent Document 1. In the cylinder head, the spark plug is installed in a structure such that the electrode portion is located at the center of the combustion chamber so that combustion in the combustion chamber proceeds evenly and quickly. The insertion hole for the fire insertion is formed to be inclined to the cylinder axis from the side. A pair of head-side bearing halves that can rotatably support the camshaft from the side form an opening formed on the surface of the cylinder head that is combined with the cylinder head cover, and the protrusion and the insertion hole are eccentrically located in a direction opposite to the tilt direction of the cylinder axis. Therefore, the pair of head-side bearing portion halves and the head-side bearing half formed on the cylinder head cover together constitute a pair of bearing portions that support the camshaft. Patent Document 1: Japanese Patent Sho 6 2-9 4 0 8 0 (Sho 6 63-2 2 7 0 7) is a micro film (Figure 1). [Summary of the Invention] (Problems to be Solved by the Invention) However, in order to prevent the front end of the spark plug electrode protruding from overheating in the combustion gas at a high temperature, the front end hardly protrudes in the combustion chamber or only protrudes a little, The insertion hole of the Martian plug is increased, and the volume of the portion of the Martian plug that does not occupy the insertion hole is large. Therefore, due to the increase in the volume of the combustion chamber, the compression ratio decreases, due to 312 / Invention Specification (Supplement) / 93-06 / 93 丨 08657 There is a single large star plug of the steam and the body is on the axle-> n. Δ is exposed again, and the tilt changes within 6 200424434 The output of the gas engine is reduced, or the electrode part is located away from the combustion chamber. If the insertion hole is retracted later, the ignition performance decreases. Therefore, it is desirable that the insertion tilt is as small as possible. On the one hand, the sealing member is sealed between the joint surface of the cylinder head and the joint surface of the cylinder head cover. Therefore, a band-shaped sealing area for sealing the two joint surfaces by the member must be ensured on both joint surfaces. Therefore, 'each shaft is the same as the above-mentioned technology composed of the head side bearing portion half and the head cover side bearing portion half. In the cylinder head where the two joint surfaces are reset to the camshaft in the cylinder axis direction, each bearing portion has a function for The sealing area that ensures the tightness of the joint surface is projected in the axial direction of the camshaft. Therefore, in the above-mentioned prior art, if the inclination of the insertion hole is to be small, because the protruding portion of the bearing portion close to the Mars plug affects the plug of the Mars plug installed in the Mars plug, and the inclination of the insertion hole is small, It is more difficult to reduce the slope of the fire. In addition, a pair of bearing portions must receive a camshaft from the intake valve and the exhaust valve that stably support rotation. However, in the case where the bearing portion is divided into two parts, in order to ensure the rigidity for stably supporting the camshaft, if the wall thickness of the bearing portion is increased, the bearing portion protrudes further to the spark plug, which makes it difficult to tilt the spark plug. Degree becomes smaller. The present invention has been invented in view of the above-mentioned problems, and the invention of claim No. 1 in the scope of patent application aims to improve the output and ignition performance of the internal combustion engine by further reducing the tilt when the spark plug is set to be inclined, and to achieve lightweighting of the internal combustion engine. In addition, the invention in the second scope of the patent application is for the purpose of miniaturizing the cylinder head. The patent application 312 / Invention Specification (Supplement) / 93-06 / 93108657 with a small hole in the seal seat is required to change the existing position. Or the direction of the reaction force of the star plug needs to be 3 times, and the invention of No. 200424434 item 4 further achieves the following object, further compacting the periphery of the cylinder head where the fuel injection valve is installed, and increasing the output of the internal combustion engine. (Means for Solving the Problem) The invention of claim 1 in the scope of the patent application is formed in the cylinder head of the internal combustion engine coupled to the cylinder with an insertion hole for inserting a spark plug having an electrode portion near the center of the combustion chamber; A bearing portion and a second bearing portion rotatably supporting a single camshaft provided with a valve cam for opening and closing an intake valve and an exhaust valve; and a joint surface of a cylinder head cover which is joined by a sealing member, comprising: supporting the cam The first bearing portion at one end of the shaft is located at a position overlapping with the insertion hole in plan view, and is located between the insertion hole and the coupling surface in the cylinder axis direction. The side wall of the cylinder head is configured to cover the entire end surface of the end portion. From the axial direction, the spark plug or a plug cap mounted on the spark plug coincides with the first bearing portion. Therefore, since there is no joint surface on the first bearing portion formed by the side wall between the insertion hole and the joint surface in the axis direction of the cylinder, there is no need to provide a sealing area to ensure tightness, and it is possible to suppress the contact with the axial direction when viewed from the axial direction. The amount of protrusion of the spark plug or plug cover provided at the overlapping position of the first bearing portion can reduce the tilt of the insertion hole with respect to the cylinder axis when viewed from the side, that is, the tilt of the spark plug or plug cover. Furthermore, the first bearing portion does not need to be thickened in order to increase the support rigidity of the camshaft when the bearing portions are separated. The invention of the second scope of the patent application is the cylinder head of the internal combustion engine of the first scope of the patent application, wherein the intake valve and the exhaust valve can be swingably supported on the pair of swing arm shafts and the exhaust valve, respectively. The air swing arm is controlled by the above 8 312 / Invention Supplement) / 93-06 / 93108657 200424434 The valve cam is controlled to open and close. The pair of swing arm shafts are located on the first bearing portion and the joint surface in the cylinder axis direction. “The two sides of the pair of swing arm shafts are supported on a pair of support portions formed by the side walls when viewed in plan view as being disposed on both sides to sandwich the rotation center line of the camshaft.” The position of the first bearing portion is clamped. Accordingly, the pair of support portions supported on the pair of support portions constituted by the side wall between the first bearing portion and the joint surface in the cylinder axis direction does not need to provide a sealing area to ensure tightness because there is no joint surface. Suppressing the amount of protrusion of the pair of support parts to the spark plug or plug cover, the tilt of the insertion hole with respect to the cylinder axis can be reduced from the side, and the tilt of the spark plug or plug cover can be reduced, so the two swing arms can be made The shaft is close to the camshaft, reducing the axial distance between the two camshafts. The invention of claim 3 is in the cylinder head of the internal combustion engine of claim 1, wherein the intake valve and the exhaust valve are respectively supported by an intake swing arm and an exhaust valve having a roller in contact with the cam of the moving valve. The swing arm is controlled by the moving valve cam to be opened and closed. The second bearing portion supports the other end of the cam shaft. The moving valve cam is provided between the first bearing portion and the second bearing portion. The first bearing portion A distance from the second bearing portion in the axial direction is substantially equal to a range in the axial direction in which the moving valve cam is provided. As a result, the contact between the moving valve cam and the swing arm becomes a rolling contact, and the friction coefficient becomes smaller. Even if the contact pressure between the moving valve cam and the swing arm increases, the wear resistance of the moving valve cam and the swing arm will not be reduced. Lowering, it is possible to reduce the size of the moving valve cam in the axial direction. Furthermore, the range of the first sum of the two ends of the camshaft 9 312 / Invention specification (Supplement) / 93-06 / 93108657 200424434 is reduced. In the cylinder head of the internal combustion engine, the installation hole of the injection valve whose rotation center line is vertical and the opening and closing of the intake valve are formed on the cylinder head in the cylinder axis direction than the axial direction. The centerline position of the ventilating chamber affects the axis of the fuel injection valve. Compared with the fuel injection valve that can more along the cylinder material to the intake port, this manual refers to the rotation of the camshaft, and the side view refers to the plane perpendicular to the axis of the cylinder ( ADVANTAGEOUS EFFECTS OF THE INVENTION According to the patent application, since the volume of the inserted combustion chamber can be reduced, the invention of the four items between the second bearing portions is a ventilation path on one side wall of the cylinder head in a plan view. The intake pipe of the fuel intake hole communicates with the venting chamber. The above-mentioned venting chamber is closer to the venting path and does not cause fuel injection. It can be installed on the vertical position. Inclined, because of the axis direction, can make the injection of the hole, reduce the spray in the direction of the centerline of the claims of the present invention, looking up Yes and parallel to the direction containing the camshaft. The invention of item 1 has a hole with a slope, so it can suppress the output of the high / internal combustion engine. According to the cam of the valve, the first item of the patent range is for the above-mentioned camshaft. The fuel injection valve is installed near the valve. Ventilation passage and shaped fuel injection valve for air intake mentioned above? L, and from the position of. The valve is vented and close to the cam in the vertical direction. This fuel injection centerline can be reduced from the exhaust port of the fuel injection valve. In the range, the axis direction means the steam from the centerline of rotation of the cylinder axis direction has the following effects. In other words, the insertion hole prevents ignition and prevents the electrode portion from receding into the hole, thereby improving the ignition performance. Furthermore, it is not necessary to increase the rigidity of the support of the camshaft and increase the thickness of the side wall when the bearing portion is divided, etc., so that the internal combustion engine can be made lighter. According to the invention in the second scope of the patent application, the following effects can be achieved in addition to the effects of the invention in the first scope of the patent application. That is, although the inclination of the Mars plug or the plug cover is reduced, it does not affect the support parts of the pair of swing arm shafts, and the two swing arm shafts can be brought closer to the cam shaft, and the shaft distance between the two shafts can be shortened. The distance makes it possible to miniaturize the cylinder head in a direction perpendicular to the rotation center line in a plan view. According to the invention in the third scope of the patent application, in addition to the invention effect in the first scope of the patent application, the following effects can be achieved. That is, the size of the moving valve cam in the axial direction can be reduced, and the interval between the first and second bearing portions decreases with the range in which the moving valve cam is installed. Therefore, the length of the cam shaft can be shortened at the same time. The cylinder head is miniaturized in the axial direction. According to the invention in the fourth scope of the patent application, in addition to the invention in the first scope of the patent application, the following effects can be achieved. That is, since the fuel injection valve is disposed close to the center line of rotation of the camshaft in the vertical direction, the fuel injection valve can be compactly installed in the cylinder head in the vertical direction, and the cylinder head can be compacted. The fuel injection valve's fuel injection centerline is further injected in the direction of the cylinder axis, which can reduce the blowing to the exhaust port, and thus can improve the output of the internal combustion engine. [Embodiment] An embodiment of the present invention will be described below with reference to Figs. 1 to 12.
參照圖1，本發明適用的内燃機E是裝載在二輪機車V 11 3丨2/發明說明書(補件)/93-06/93108657 200424434 上的單汽缸四衝程火星點火式内燃機。 踏板式二輪機車V具有：帶前車架1和後車架2的車體 框架F;可以轉動地支承在前車架1的頭管1 a上的前叉3; 可以轉動地支承在臂4上的前輪6，上述臂4可以擺動地 支承在前叉3的下端；連接前叉3和臂4的前緩衝器5 ; 固定在前叉3上端的手柄7 ;可以擺動地支承在枢軸8上 的翼式動力單元P，上述樞軸8設置在車體框架F的後車 架2上；可以轉動地支承在動力單元P的後端的後輪1 0 ; 連接後車架2和動力單元P的後部的後缓衝器9 ;安裝於 後車架2上收置頭盔1 1等物品的收置箱1 2 ;安裝在收置 箱1 2的上部可以開閉收置箱1 2的開口的蓋板1 3、安裝在 前車架1 1上的燃料箱1 4、覆蓋車體框架F的車體護罩1 5。 車體框架F是通過螺栓相互結合的前車架1和後車架2 的兩部分分體型車架。前車架1具有：頭管1 a ;從頭管1 a 向下延伸的下車架1 b、從下車架1 b的下端向後大致水平 延伸的左右一對踏板支架1 c，它們是通過鑄造一體成型的 構件。而且，後車架2是左右一對主框架2 a、連接到兩個 主框架2a上的多個橫向構件（圖中未示出）通過鑄造一體 成型的構件。然後，左右踏板支架1 c的後端部分別通過螺 栓與左右主框架2a的前端部連接。 車體護罩1 5具有：覆蓋頭管1 a的前部的前擋板1 5 a ; 覆蓋頭管1 a和下車架1 b的後部而且位於騎車人的腳部前 方的擋腿板1 5 b ;承載騎車人的腳的踏板1 5 c、設置在踏板 1 5 c的下方的覆蓋支承左右踏板支架1 c的下擋板1 5 d ;和 12 312/發明說明書(補件)/93-06/93108657 200424434 覆蓋左右主框架2 a的後擋板1 5 e。 燃料箱1 4位於左右踏板支架1 c之間，配置在踏板1 5 c 和下擋板1 5 d形成的容納空間内。燃料箱1 4内的燃料通過 燃料泵抽出來，供給到内燃機的所述的汽化器和燃料喷射 閥3 6中。 動力單元P具有：内燃機E，橫向設置，具有在左右方 向上延伸的曲柄軸；V帶型自動變速器Μ，作為把内燃機E 的動力傳遞給後輪的傳動裝置。内燃機Ε具有：連接到自 動變速器Μ的變速箱Μ 1的曲柄箱和從該曲柄箱開始相對於 水平方向稍微向上傾斜地向前延伸的水平設置的汽缸 2 0。上述曲柄軸收置在通過上述曲柄箱形成的曲柄室内， 可以轉動地支承在所述曲柄箱内。另外，所述曲柄軸的轉 動通過自動變速器Μ根據内燃機的轉動速度被無級變速傳 遞到後輪1 0，後輪1 0通過内燃機Ε被轉動驅動。而且， 後述的汽缸頭21的上方接近地配置著作為車體側構件的 收置箱1 2，在汽缸頭21的前方形成比較狹窄的間隔，配 置踏板1 5 c。其中，水平設置的汽缸2 0從上述曲柄軸的轉 動中心線方向看，汽缸軸線L 1相對於水平方向成角度的範 圍在45度以下。 參照圖2〜圖8，進一步說明内燃機Ε。首先參照圖2和 圖3，SOHC型水冷式内燃機Ε具有：活塞25可往復運動地 嵌合的汽缸2 0 ;汽缸2 0上通過4根頭螺栓B 1〜B 4結合的 汽缸頭2 1、通過密封構件2 4結合到汽缸頭2 1的結合面2 3 上的汽缸頭蓋2 2、使汽缸2 0的裙部構成其一部分的上述 13 312/發明說明書(補件)/93-06/93108657 200424434 曲柄箱。 嵌合到汽缸2 0的汽缸孔2 0 a内的活塞2 5通過桿2 6連 接到上述曲柄軸上，把活塞25的往復運動變更為上述曲柄 軸的轉動運動。 同時參照圖4，在汽缸頭2 1上形成有··在與汽缸孔2 0 a 和汽缸轴線L 1的方向A 1相對的壁面上形成的凹部構成的 燃燒室2 7、有在燃燒室2 7上開口的一對進氣孔2 8 a的進 氣口 2 8、有在燃燒室2 7上開口的一對排氣孔2 9 a的排氣 口 2 9、插入火星塞3 0的插入孔31，而且還設置有分別開 閉一對進氣孔2 8 a的一對進氣閥3 2和分別開閉一對排氣孔 2 9 a的一對排氣閥3 3。 在打開進氣口 2 8的入口 2 8 b開口的汽缸頭21的進氣側 的外面2 1 a上，具有作為主燃料供給裝置的汽化器的進氣 裝置的進氣管3 4與入口 2 8 b連通連接，在打開排氣口 2 9 的出口 2 9 b的汽缸頭2 1的排氣側的外面2 1 b上，連接有排 氣裝置的排氣管3 5 (參照圖1 )。而且，汽缸頭2 1的進氣 側形成的安裝孔2 1 c (參照圖2、圖6、圖7 )處，鄰近進 氣口 28安裝有燃料喷射閥36，作為在内燃機E開始工作 或者加速等時供給附加燃料的燃料增量用的輔助燃料供給 裝置。 其中，進氣側是指相對於包括凸輪軸4 1的轉動中心線 L 2汽缸軸線L1平行的平面Η1設置進氣閥3 2的一側，排 氣側是指相對於平面Η 1設置排氣閥3 3的一側。 而且，含有從上述汽化器和燃料噴射閥36供給的燃料 14 312/發明說明書(補件)/93-06/93108657 200424434 的混合氣體通過活塞2 5的下降進氣行程，從進氣口 2 8通 過打開的一對進氣閥3 2被吸入燃燒室2 7内。被吸入汽缸 2 0内的混合氣體在壓縮行程通過上升活塞2V5被壓縮後， 通過火星塞3 0被點火燃燒，在膨脹行程通過燃燒氣體的壓 力下降的活塞2 5通過桿2 6轉動驅動上述曲柄,。燃燒氣 體在排氣行程中通過打開的一對排氣閥3 3作為排出氣體 從燃燒室2 7排出到排氣口 2 9，進一步通過排氣管3 5和上 述排氣裝置的消聲器3 7 (參照圖1 )排出到外部。 參照圖2、圖3和圖5，通過閥彈簧3 8被向關閉方向增 加勢能的各個進氣閥3 2和各個排氣閥3 3通過設置在動閥 室3 9内的動閥裝置4 0開閉，所述動閥室3 9是由汽缸頭 2 1和汽缸頭蓋2 2形成的。動閥裝置4 0具有：單一凸輪軸 4 1，可以轉動地支承在形成於汽缸頭2 1上的一對軸承部 5 1、5 3上；進氣擺臂4 4和排氣擺臂4 5，通過設置在凸輪 軸4 1上的一對操縱閥凸輪的進氣凸輪4 2和排氣凸輪4 3 擺動；一對擺臂軸4 6、4 7，支承在汽缸頭21上，分別可 以擺動地支承兩個擺臂4 4、4 5。 凸輪軸4 1通過由設置在上述曲柄軸之間的動力傳遞機 構傳遞的上述曲柄軸的動力，以其轉動速度的1 / 2轉動驅 動。上述傳動機構由如下構件構成：設置在上述曲柄軸上 的作為驅動轉動體的驅動輪、設置在凸輪軸4 1上作為從動 轉動體的凸輪4 8、和作為掛接上述驅動輪和凸輪4 8上的 無端傳送帶的定時鏈4 9構成。 而且，同時參照圖6和圖7，在汽缸軸線A1方向上位於 15 312/發明說明書(補件)/93-06/93108657 200424434 比結合面2 3更靠近汽缸2 0的位置上的一對軸承部5 1、5 3 由如下構件構成：通過滾珠軸承構成的軸承5 0支承在軸方 向A 2上的凸輪軸4 1的一端4 1 a的第一軸承部5 1、和通過 滾珠軸承構成的軸承5 2支承在軸方向A 2上的另一端4 1 b 的第二軸承部5 3。 在汽缸軸線方向A 1方向上位於插入孔3 1和結合面2 3 之間的第一軸承部5 1通過軸方向A 2上的汽缸頭2 1的一個 側壁5 4的一部分構成，即侧壁5 4上形成燃燒室2 7而且形 成有插入口 3 1的燃燒室壁5 4 a和結合面2 3的法蘭5 4 a之 間的中間壁5 4 c的一部分構成，具有覆蓋整個一端4 1 a的 端面4 1 a 1的形狀，通過嵌合在第一軸承部5 1的内面，即 通過在側.壁5 4的動閥室3 9 —側的壁面上形成的有底凹部 5 5内嵌合的軸承5 0支承一個端部4 1 a。第一軸承部5 1位 於從平面上看與插入孔3 1重合的位置上（參照圖5、圖7 )。 而且，第一軸承部5 1的軸方向A 2上的外面5 1 a大致與垂 直於轉動中心線L 2的平面平行（參照圖5 )。 而且，參照圖7，第一軸承部51位於從軸方向A 2看與 火星塞30或者安裝火星塞30的塞蓋56重合的位置。而 且，第一軸承部5 1在側壁5 4上，位於插入進氣側的頭螺 栓B1 (參照圖3 )的插入孔5 7形成的突起部5 8與插入排 氣側的頭螺栓B 3的插入孔5 9形成的突起部6 0之間（參照 圖7 ) 〇 參照圖5、圖6和圖8，為了使動閥室3 9與傳動室61 隔開，第二軸承部5 3由隔離壁6 2的一部分構成，所述隔 16 312/發明說明書(補件)/93-06/93108657 200424434 離壁6 2從一體形成在汽缸頭2 1上的燃燒室2 7 —側朝向汽 缸頭蓋2 2，大致與垂直於轉動中心線L 2的平面平行延伸， 通過嵌合到隔離壁6 2上形成的通孔6 3内的軸承5 2支承凸 輪軸4 1的另一端4 1 b。第二軸承部5 3平視位於與燃燒室 2 7部分重合的位置（參照圖5 )。而且，第二軸承部5 3在 隔離壁6 2上，位於形成有插入進氣側的頭螺栓B 2 (參照 圖3 )的插入？L 6 4的突起部6 5與形成有插入排氣側的頭 螺栓B 4 (參照圖3 )的插入孔6 6的突起部6 7之間。 參照圖2、圖3和圖5，凸輪軸41上，進氣凸輪4 2和 排氣凸輪4 3設置在第一軸承部5 1和第二軸承部5 3的軸方 向A 2之間，第一軸承部51和第二軸承部5 3的軸方向A 2 上的間隔大致等於設置進氣凸輪4 2與排氣凸輪4 3的軸方 向A 2上的範圍D (參照圖5 )。其中，排氣凸輪4 3位於與 汽缸軸線L1交叉的位置上。而且，在另一端41 b，凸輪4 8 夾住第二軸承部53，位於與進氣凸輪相反的一側，而且結 合到臨近配置定時鏈4 9的傳動室6 1内的部分。 進氣擺臂4 4是轉動擺臂，具有：被支承部4 4 a，形成有 插入擺臂軸4 6的通孔；驅動部4 4 b，從被支承部4 4 a向凸 輪軸4 1延伸，而且可轉動地設置在與進氣凸輪4 2滾動接 觸的輥子4 4 d上；一對工作部4 4 c，從被支承部4 4 a分別 向一對進氣閥3 2延伸，並可以與這些進氣閥3 2接觸。 而且，排氣擺臂4 5分別是轉動擺臂，具有：被支承部 4 5 a，形成有插入擺臂軸4 7的通孔；驅動部4 5 b，從被支 承部4 5 a向凸輪軸4 1延伸，而且可轉動地設置在與·排氣凸 17 312/發明說明書(補件)/93-06/93108657 200424434 輪4 3滾動接觸的親子4 5 d上；一對工作部4 5 c，從被支承 部4 5 a分別向一對排氣閥3 3延伸，可以與這些排氣閥3 3 接觸。 其中，各個輥子44d、4 5d通過固定到驅動部4 4c、45c 上的支承軸44e、45e的周圍設置的多個滾針44f、45f可 以轉動地支承。而且，各個擺臂44、45通過嵌入各個凸輪 軸46、47上的壓縮線圈彈簧構成的定位彈簧68的回復力 在軸方向A2上位於所定位置。 因此，各個進氣閥3 2和各個排氣闊3 3通過藉助進氣凸 輪4 2擺動的進氣擺臂4 4和藉助排氣凸輪4 3擺動的排氣擺 臂45，通過進氣凸輪42和排氣凸輪43與上述曲柄軸同步 轉動而且以規定時間分別開閉。 兩個擺臂軸4 6、4 7設置成與凸輪軸4 1的轉動中心線L 2 平行，設置成平視夾住凸輪軸41的轉動中心線L 2和凸輪 軸4 1，位於其兩側。同時參照圖6〜圖8，各個擺臂軸4 6、 4 7的一個端部即支承在中間壁5 4 c的一部分構成的第一支 承部7 0、7 1上，另一端支承在汽缸軸線方向A1上位於第 二軸承部5 3與結合面2 3之間的隔離壁6 2的一部分構成的 第二支承部7 2、7 3上。 因此，在汽缸軸線方向A1上比結合面2 3的法蘭5 4 b更 靠近汽缸2 0的位置上的支承部7 1〜7 3上形成擺臂軸4 6、 47的端部嵌合孔74〜77。而且，一對第一支承部70、71 平視位於夾住第一軸承部5 1的位置上（參照圖6、圖7 )。 參照圖4〜圖7，火星塞3 0的前端形成的具有擰入陽螺 18 312/發明說明書(補件)/93-06/93108657 200424434 紋部3 0 a的陰螺紋部3 1 a的插入孔3 1具有在燃燒室名 的外面上開口的外面側開口的開口部3 1 b和位於燃燒 5 4 a的内面的在燃燒室2 7的頂面上大致中央開口的燃 侧開口部3 1 c。因此，在陽螺紋部3 0 a沒有從燃燒室 露出的狀態下，火星塞3 0安裝在燃燒室壁5 4 a上，從 紋部30a突出的的電極部30c臨近燃燒室27的大致 部。因此，中心電極3 0 c 1和側面電極3 0 c 2位於與汽 線L1交叉的位置上。 而且，插入孔31形成在與平面H1交叉的位置上（ 圖7 )，它的開口部31 c與汽缸軸線L1交叉。而且，女 所示，插入孔3 1從側面看相對於汽缸軸線L1在與第 承部5 3的位置相反的一側傾斜，火星塞3 0和塞蓋5 6 星塞3 0同軸的部分5 6 a也與插入孔31相同角度傾斜 在火星塞3 0插入汽缸頭2 1中的狀態下，從燃燒室5 向汽缸頭蓋22延伸的火星塞30被配置在凹部78内， 凹部是由三個側壁54包圍形成的，即作為在與平面 直的方向A3(平視與轉動中心線L2垂直的方向）上 個的側壁5 4的一部分的兩個突起部5 8、6 0和作為所 方向A2上向裏方向上側壁54的一部分的中間壁54c 而成。而且，與點火線圈相連的高壓點火線連接到火 30上，因此安裝在火星塞30上的塞蓋56位於所述凹 内，在兩個第一支承部7 0和71之間。 參照圖3、圖5，凸輪軸41的另一端41 b上，在臨 方向A 2方向上，設置有作為輔助設備的冷卻水泵8 0 312/發明說明書(補件)/93-06/93108657 t 54a 室壁 燒室 27内 陽螺 中心 缸軸 參照 3圖5 二軸 與火 〇 Ϊ 54a 所述 H1垂 的兩 述軸 包圍 星塞 部78 近軸 ，其 19 200424434 中心線與凸輪軸41的轉動中心線L 2 —致。 安裝在汽缸頭21上的冷卻水泵8 0具有：泵體81，固定 在設置於傳動室6 0内汽缸頭2 1的軸方向A 2上的另一個側 壁7 9上；泵蓋8 2，位於汽缸頭21的外部，與泵體81結 合，在泵體81之間形成泵室8 3 ;支承軸8 4，支承在泵體 81和泵蓋8 2之間；渦輪8 5，配置在泵體81内，可以轉動 地支承在支承軸84上，具有位於泵室83内的多個葉片 85b ° 冷卻水泵8 0藉助在與凸輪軸4 1之間設置的驅動機構通 過凸輪轴4 1驅動。上述驅動機構由如下部分構成：驅動轉 動體86,在作為凸輪軸41的另一端41b鄰近傳動室61的 部分的端面41bl上，與凸輪48通過突起部B5結合而成； 和作為渦輪8 5 —部分的本體部8 5 a。臨近凸輪軸4 1的部 分設置在定時鏈4 9内側的碗狀凸輪鏈内設置的驅動轉動 體86具有固定在圍繞泵體81的周圍部分的圓環狀永久磁 鐵86c，渦輪85的本體部85a具有固定在與永久磁鐵86c 的徑向相對位置上的圓環狀永久磁鐵8 5 c。因此，若驅動 轉動體86與凸輪軸一起轉動，通過永久磁鐵86c、85c磁 性結合在驅動轉動體8 6上的渦輪8 5轉動，把流入的冷卻 水壓送到泵室83内。 而且，在泵蓋8 2上設置有根據冷卻水的溫度控制汽缸 2 0和汽缸頭2 1内的冷卻水流的恒溫器9 0。恒溫器9 0具有 開閉流入通路9 3的閥體9 2，流入通路9 3形成在通過根據 冷卻水的溫度膨脹或者收縮的石蠟9 1驅動泵蓋8 2上。 20 312/發明說明書(補件)/93-06/93108657 200424434 如圖5所示，在内燃機E暖機時，閥體9 2 ® 路93，阻止來自冷卻器（圖中未示出）的冷卻 水泵8 0内，因此能夠通過冷卻水栗8 0壓送把 流入的冷卻水，在汽缸2 0和汽缸頭21内迴圈 成之後，由於閥體9 2打開流入通路9 3，上述冷 變成低溫的冷卻水在如下路徑上迴圈，被壓送 水泵8 0内，然後在汽缸和汽缸頭21冷卻之後 上述冷卻器。 參照圖2、圖3和圖6，對應於汽缸頭21的 在該側上在作為垂直方向A 3的汽缸頭2 1的一 壁6 9上形成的安裝孔2 1 c中安裝有燃料噴射馬 為汽缸頭蓋2 2的上部的汽缸頭蓋的進氣一側， 述曲柄室的通氣通路R連通的通氣室100設置 39和傳動室61的上方鄰接。 通氣通路R由與形成在汽缸頭21上的通氣| 的通氣通路1 2 0和汽缸側通氣通路（圖中未示 所述汽缸側通路在汽缸2 0上形成，一端與通| 連通、另一端與上述曲柄室連通。由臨近動闊3 室6 1的上方的沿著汽缸軸線方向A 1延伸的貫 通氣通路120由如下部分構成：在結合面23上 室1 0 0 —側開口的開口 1 2 0 a ;貫通孔，具有在 的結合面2 1 h上的開口和與上述汽缸側通氣通 通的汽缸2 0側的開口 1 2 0 b (參照圖4 )。 在接近上壁6 9的外側面6 9 a的狀態下沿著； 312/發明說明書(補件)/93-06/93108657 ^閉流入通 水流入冷卻 從旁路94 。在暖機完 卻器放熱， 流入到冷卻 ，在返回到 進氣一側， 個側壁的上 3 3 6，在作 與連通到上 成與動閥室 [1 00連通 出）構成， L通路1 20 [3 9和傳動 通孔構成的 開口的通氣 與汽缸2 0 路的一端連 卜側面6 9 a 21 200424434 延伸的燃料噴射閥3 6設置在平視與通氣室1 〇 〇 上，而且與燃料供給管連接的端部3 6 a位於接 的法蘭69b的位置。而且，參照圖2、圖7，火 3 6在汽缸軸線方向A 1相對於通氣室1 0 0靠近 或者汽缸2 0的位置，而且位於從軸方向看與这 重合的位置。 參照圖2、圖9、圖1 0和圖1 2 ’相對於在汽 A 1上與結合面2 3在相同平面的平面，只位於 一側的通氣室1 0 0由如下部分構成：第一室1 缸頭蓋2 2的最上部構成的通氣室形成部1 0 3上 部構成；第二室102，由用於覆蓋第一室101 通氣室形成部1 〇 3上的帽狀蓋1 0 4形成。 通氣室形成部1 0 3具有平板狀的底壁1 0 3 a， 在與結合面23和結合面22相同的平面上，具 面2 2 a的一部分的上側面1 0 3 b，通過所述底智 開口 1 2 0 a。因此，在上側面1 0 3 b上形成有安 2 4的密封溝1 0 3 c，用於使開口 1 2 0 a的上沿1 的結合面2 3之間密封。而且，底壁1 0 3 a上形 1 0 5和油返回通路1 0 6，由任何通孔構成，所ϋ 使通氣通路120和第一室101連通，油返回通 入口路105下方的位置。 同時蒼照圖3、圖6 ’在〉缸21上形成有隔 隔離通氣通路1 2 0和動閥室3 9以及傳動室6 1 與結合面2 3位於同一平面上的端面1 0 7 a。隔 312/發明說明書(補件)/93-06/93108657 重合的位置 近上壁6 9 然料噴射閥 進氣孔28a L氣通路1 2 0 缸軸線方向 汽缸頭蓋2 2 01 ，在由汽 形成的凹陷 氣密安裝在 該底壁1 0 3 a 有構成結合 t 1 0 3 a覆蓋 裝密封構件 20al與規定 成有入口路 [入口路1 0 5 路1 0 6位於 離壁1 0 7， ，並且具有 離壁1 0 7具 22 200424434 有突出部107b，該突出部107b在平視在上下方向延伸的 隔離壁6 2與隔離壁1 0 7連接的部位，沿著隔離壁6 2朝動 閥室3 9 —側向下方突出。在突出部1 〇 7 b上形成有與通氣 通路1 0 2内的油返回通路1 0 6連通的槽1 0 8。如圖9所示， 槽1 0 8在底壁1 0 3 a的下緣1 0 3 a下方延伸，以便它的最下 部不覆蓋底壁1 〇 3 a，由此形成的出口 1 1 0中與動閥室3 9 和傳動室6 1連通。因此，通過槽1 0 8形成連通通氣室1 0 0 和動閥室3 9以及傳動室6 1的連通通路1 0 9。 一方面，蓋1 0 4在通過密封構件1 1 1密封安裝在通氣室 形成部1 0 3上形成的結合面1 0 3 d上的狀態下，通過三個螺 栓B 6與通氣室形成部1 0 3固定到汽缸頭21上。因此，蓋 1 0 4的結合面1 0 3 d和結合面1 0 4 d上形成有安裝密封構件 1 1 1的密封溝1 0 4 c，而且蓋1 0 4的法蘭上形成有通孔 1 0 4 e，貫通在通氣室形成部1 0 3上形成的貫通孔1 0 3 e，使 擰入在汽缸頭2 1的法蘭6 9上形成的螺紋孔2 1 e的各個螺 栓B6貫通。 而且，蓋104上，在通氣室100中設置有出口路112， 使後面所述的多個突出部1 0 3 k、1 0 3丨n、1 0 4 k、1 0 4丨η夾在其 與入口路105之間。出口路112在這裏是通過壓入蓋104 内的管接頭11 3形成。管接頭11 3上連接有環流管（圖中 未示出），該環流管形成與上述進氣裝置的進氣通路連通的 環流通路。通氣室1 0 0和上述進氣通路通過出口路1 1 2和 上述環流通路連通。 參照圖9、圖1 1和圖1 2，為了從含有流入通氣室1 〇 〇 23 3丨2/發明說明書(補件)/93-06/93108657 200424434 内的油分的漏氣中分離出油，在通氣室形成部1 0 3和蓋1 ο 4 上形成有多個突出壁 l〇3k、103m、103n、104k、104m、104η， 這些突出壁具有相互突出配合的配合部l〇3kl、103ml、 103η卜104kl、104ml、104nl而且把通氣室劃分成迷宮狀。 因此，從入口路1 0 5流入通氣室1 0 0内的漏氣在通氣室1 0 0 内一邊在這些突出壁 103k、103m、103n、104k、104m、104η 上碰撞，一邊向出口路1 1 2流動’促進油分離。 因此，含有内燃機Ε潤滑用的油的漏氣在從上述曲柄室 通過通氣室120之後，主要從入口路105流入通氣室100。 流入通氣室100的漏氣一邊碰撞在突出壁l〇3k、103m、 103n、104k、104m、104n上，一邊在劃分為迷宮狀區域的 通氣室1 0 0内流動，油被分離。分離出油的漏氣通過上述 進氣通路的負壓被抽出，通過出口路1 1 2和上述環流通路 流入上述進氣通路，進一步流入燃燒室2 7内燃燒。而且， 分離出的油從油返回路1 0 6流入連通路1 0 9，流下連通路 1 0 9流入傳動室61内，供給動閥裝置40或者上述傳動機 構潤滑。 下面，說明如上結構的實施例的作用及其效果。 在汽缸頭2 1上形成有插入火星塞3 0的插入孔3 1，所述 火星塞30具有臨近燃燒室27的大致中央位置的電極部 6 0 c。在由此的汽缸頭21上，支承單個凸輪軸41的一端 4 1 a的第一轴承部5 1位於平視與插入孔3 1重合的位置 上，而且在汽缸轴線方向A 1方向上位於插入口 3 1與結合 面2 3之間，而且覆蓋由汽缸頭21的側壁5 4構成的一端 24 312/發明說明書(補件)/93-06/93108657 200424434 41a的整個端面41al，從軸方向A2看火星塞30或者 5 6與第一軸承部5 1重合，在第一軸承部5 1沒有結名 2 3，因此不需要設置用於確保密封性的密封區域，因 夠控制從軸方向A 2方向看向第一軸承部5 1重合位置 置的火星塞3 0或者塞蓋5 6伸出量，由於可減小從側 插入孔3 1相對於汽缸軸線L1傾斜，即減小火星塞3 0 缸蓋5 6的傾斜，因此由於插入孔31中火星塞3 0沒有 空間3 1 d (參照圖5 )，能夠抑制燃燒室的容積增大， 内燃機的輸出，而且抑制電極部3 0 c在插入孔3 1内後 能夠提高點火性能。而且，第一軸承部5 1不需要在分 承部等情況下需要提高提高凸輪軸4 1的支承剛性而3 側壁54的厚度，因此能夠使内燃機輕量化。 進氣閥3 2和排氣閥3 3通過藉助分別可以擺動支承 對擺臂軸4 6、4 7上的進氣擺臂4 4和排氣擺臂4 4由進 輪4 2和排氣凸輪4 3開閉，一對擺臂軸4 6、4 7在汽缸 方向A 1上位於第一軸承部5 1和結合面2 3之間，而且 設置成夾凸輪軸4 1的轉動中心線L 2，位於其兩側， 擺臂軸4 6、4 7的一端支承在通過側壁5 4構成的一對 支承部7 0、71上，這兩個支承部7 0、71平視位於夾 軸承部5 1的位置上，由於各個支承部7 0〜7 3上沒有 面2 3，因此不需要設置確保密封性的密封區域，能夠 兩個第一軸承部7 0、7 1中向火星塞3 0或者塞蓋5 6的 量，由於能夠縮小從側面看插入孔3 1相對於汽缸軸| 傾斜，即火星塞3 0和汽缸蓋5 6的傾斜，雖然火星塞 312/發明說明書(補件)/93-06/93108657 塞蓋 面 此能 上設 面看 和汽 佔據 提高 退， 割軸 f加 在一 氣凸 軸線 平視 一對 第一 第一 結合 控制 伸出 L L1 30 25 200424434 或者塞蓋5 6的傾斜減小了 ，但是沒有對一對擺臂軸4 6、 4 7的兩個第一支承部7 0、7 1產生干擾，使兩個擺臂軸4 6、 4 7接近凸輪軸4 1，能夠縮短所述軸間距離’因此平視在與 轉動中心線L 2垂直的方向A 3上，能夠使汽缸頭2 1小型化。 進氣擺臂4 4和排氣擺臂4 5是分別具有與進氣凸輪4 2 和排氣凸輪4 3接觸的輥子4 4 d、4 5 d的滾動擺臂，第二軸 承部5 3支承在凸輪軸41的另一端部41 b上，進氣凸輪4 2 和排氣凸輪4 3設置在第一軸承部5 1和第二軸承部5 3之 間，在第一軸承部5 1和第二軸承部5 3的軸向A 2方向上的 間隔大致等於設置有進氣凸輪4 2和排氣凸輪4 3設置的軸 向A 2範圍D，各個凸輪4 2、4 3與各個擺臂4 4、4 5的接觸 變成滾動接觸，摩擦係數變小，因此即使各個凸輪4 2、4 3 與各個擺臂4 4、4 5的接觸壓力提高，進氣凸輪4 2、排氣 凸輪4 3、進氣擺臂4 4以及排氣擺臂4 5的耐摩性也不下 降，因此能夠減小進氣凸輪42和排氣凸輪43在軸方向A2 上的寬度，分別支承凸輪軸41的兩端部4 1 a、4 1 b的第一 和第二軸承部5 1、5 3之間的間隔回應於進氣凸輪4 2和排 氣凸輪4 3設置的範圍D減小，因此能夠減小凸輪軸41的 長度，能夠在軸方向A 2方向上使汽缸頭2 1小型化。因此， 即使在凸輪軸4 1的另一端部4 1 b上臨近軸方向A 2設置冷 卻水泵8 0的情況下，也能夠防止在軸方向A 2方向上的内 燃機E的汽缸頭2 1部分引起的内燃機E大型化。 在汽缸頭2 1的上壁6 9形成有安裝燃料噴射閥3 6的安 裝孔2 1 c、與形成在汽缸頭蓋2 2上的通氣室1 0 0連通的通 26 312/發明說明書(補件)/93-06/93108657 200424434 氣通路1 2 0，燃料喷射閥3 6在汽缸軸線方向A 1相對 氣室100靠近進氣口 28的進氣孔28a，在軸方向 A2 上看位於與通氣通路1 2 0重合的位置上，在汽缸頭2 ] 燃料喷射閥3 6不對通氣通路1 2 0和容積大的通氣室 影響，因此能夠在垂直方向A3上（或者上下方向）設 靠近凸輪軸41的轉動中心線L 2的位置上，能夠在汽 21上在垂直方向A3上（或者上下方向上）緊湊地設 料噴射閥3 6，能夠使汽缸2 1周圍緊湊，因此從軸方 方向（或者上述曲柄軸的轉動中心線方向）看能夠使 喷射閥3 6相對於汽缸軸線L1的傾斜減小，能夠使出 料喷射閥3 6的燃料朝向進氣孔2 8 a喷射，使燃料的喷 心線更加沿著汽缸軸線方向A 1，能夠減少吹到排氣口 能夠提高内燃機的輸出。因此，能夠使汽缸頭2 1周圍 緊凑，因此在踏板1 5 c的後面，而且在收置箱1 2的下 成比較狹窄的空間，能夠配置汽缸頭2 1。 通氣室1 0 0通過作為汽缸頭蓋2 2的一部分的通氣] 成部1 0 3和安裝在通氣室形成部1 0 3處的蓋1 0 4形成 氣室1 0 0不受通過小型化汽缸頭2 1形成的動.閥室3 9 動閥裝置4 0的設置的限fil ，而且不伴隨著汽缸頭2 1 缸頭蓋2 2大型化而增加動閥室3 9的容積。而且，平 位於與通氣室1 0 0重合的位置上，而且端部3 6 a能夠 與位於接近法蘭6 9 b的位置燃料噴射閥3 6互相影響， 能夠形成大容積的通氣室1 0 0，能夠提高漏氣中含有！ 的分離功能，而且由於在汽缸頭2 1中沒有形成通氣| 312/發明說明書(補件)/93-06/93108657 於通 方向 .中， 100 置在 缸頭 置燃 向A 2 燃料 自燃 射中 29， 更加 面形 r形 ，通 内的 和汽 視看 避免 因此 的油 27 200424434 1 0 0，因此能夠實現汽缸頭2 1小型化。 下面，對作為變更上述實施例一部分的實施方式的變更 結構進行說明。 内燃機Ε具有一對進氣閥3 2和一對排氣閥3 3，但是進 氣閥和排氣閥中的任何一方是一對閥門，另一方是一個閥 門的結構也可以，而且進氣閥和排氣閥中任何一方都是一 個閥門的結構也可以。 在上述實施例中，燃料供給裝置由汽化器和燃料噴射閥 3 6構成，但是只由安裝在靠近進氣口 2 8的汽缸頭2 1上的 燃料噴射閥構成也可以。而且，内燃機Ε雖然在上述實施 例中是使用在車輛上，但是也可以用於車輛以外的機器中。 【圖式簡單說明】 圖1顯示本發明之實施形態，為安裝了具有根據本發明 的汽缸頭的内燃機的二輪機車的左側視圖。 圖2為圖1所示内燃機的主要部分的剖面圖，為汽缸頭 大致沿著圖3中的I I a - I I a線剖開的剖面圖，是凸輪軸和 擺臂沿著圖3中的I I b - I I b線所作的剖面圖。 圖3為沿著圖2中的I I I _ I I I線所作的剖面圖。 圖4為沿著圖2中的I V - I V線所作的剖面圖。 圖5為沿著圖3中的V-V線所作的剖面圖。 圖6為圖1中的内燃機的汽缸頭的立體圖。 圖7為圖5的汽缸頭沿著V I I - V I I線所作的剖面圖。 圖8為沿著圖7中的V I I I - V I I I線所作的剖面圖。 圖9為圖2中的汽缸頭蓋的通氣室形成部沿著I X - I X線 28 312/發明說明書(補件)/93-06/93108657 200424434 所作的别面圖。 圖1 0為圖2中的汽缸頭蓋的 所作的剖面圖。 圖11為沿著圖9中的XI_XI 圖12為圖2中形成通氣室的 面圖。 (元件符號說明） 通氣室形成部沿著X-X線 線所作的剖面圖。 蓋的X I I - X I I線所作的剖Referring to FIG. 1, the internal combustion engine E to which the present invention is applicable is a single-cylinder four-stroke Mars-ignition internal combustion engine mounted on a two-wheel locomotive V 11 3 丨 2 / Invention Specification (Supplement) / 93-06 / 93108657 200424434. The scooter type V has: a body frame F with a front frame 1 and a rear frame 2; a front fork 3 rotatably supported on a head pipe 1 a of the front frame 1; and a rotatably supported arm 4 On the front wheel 6, the above arm 4 is swingably supported at the lower end of the front fork 3; the front bumper 5 connecting the front fork 3 and the arm 4; the handle 7 fixed at the upper end of the front fork 3; and it is swingably supported on the pivot 8 Wing-type power unit P, the above-mentioned pivot shaft 8 is provided on the rear frame 2 of the body frame F; the rear wheels 10 are rotatably supported at the rear end of the power unit P; the rear frame 2 and the power unit P are connected Rear bumper 9 at the rear; storage box 12 for mounting helmets 11 and other items installed on the rear frame 2; a cover plate installed at the upper part of the storage box 12 for opening and closing the storage box 12 1 3. Fuel tank 1 installed on front frame 11 1 4. Body cover 15 covering body frame F. The vehicle body frame F is a two-part split-type frame of a front frame 1 and a rear frame 2 which are coupled to each other by bolts. The front frame 1 has a head pipe 1 a, a lower frame 1 b extending downward from the head pipe 1 a, and a pair of left and right pedal brackets 1 c extending substantially horizontally rearward from the lower end of the lower frame 1 b. One-piece component. Further, the rear frame 2 is a pair of left and right main frames 2a, and a plurality of cross members (not shown) connected to the two main frames 2a are integrally formed by casting. The rear end portions of the left and right pedal brackets 1c are connected to the front end portions of the left and right main frames 2a by bolts, respectively. The vehicle body cover 15 includes a front bezel 15 a covering a front portion of the head pipe 1 a, and a leg shield covering a rear portion of the head pipe 1 a and the lower frame 1 b and located in front of a foot of a cyclist. 1 5 b; pedals 1 5 c carrying the feet of the cyclist, lower bezels 1 5 d that cover the left and right pedal brackets 1 c under the pedals 1 5 c; and 12 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 The tailgates 1 5e covering the left and right main frames 2a. The fuel tank 14 is located between the left and right pedal brackets 1 c, and is arranged in an accommodation space formed by the pedals 15 c and the lower baffle 15 d. The fuel in the fuel tank 14 is drawn out by a fuel pump and supplied to the carburetor and fuel injection valve 36 of the internal combustion engine. The power unit P includes: an internal combustion engine E, which is disposed laterally and has a crank shaft extending in the left-right direction; and a V-belt type automatic transmission M as a transmission device that transmits the power of the internal combustion engine E to the rear wheels. The internal combustion engine E includes a crank case connected to the transmission M 1 of the automatic transmission M, and a horizontally-arranged cylinder 20 extending from the crank case and extending forward obliquely upward with respect to the horizontal direction. The crank shaft is housed in a crank chamber formed by the crank case, and is rotatably supported in the crank case. In addition, the rotation of the crankshaft is transmitted to the rear wheels 10 by the continuously variable transmission according to the rotation speed of the internal combustion engine through the automatic transmission M, and the rear wheels 10 are rotationally driven by the internal combustion engine E. Further, a storage box 12 which is a vehicle-body-side member is disposed close to a cylinder head 21 (to be described later), and a relatively narrow gap is formed in front of the cylinder head 21, and a pedal 15c is disposed. Among them, the horizontally arranged cylinder 20 is viewed from the rotation centerline direction of the crank shaft, and the range of the cylinder axis L 1 with respect to the horizontal direction is 45 degrees or less. The internal combustion engine E will be further described with reference to FIGS. 2 to 8. First referring to FIG. 2 and FIG. 3, the SOHC water-cooled internal combustion engine E has a cylinder 20 that is reciprocably fitted with a piston 25; a cylinder head 2 that is connected to the cylinder 20 by four head bolts B 1 to B 4 1. Cylinder head cover 2 which is joined to the joint surface 2 3 of the cylinder head 2 1 by the sealing member 2 4 2. The above-mentioned 13 312 / Invention specification (Supplement) / 93-06 / 93108657 which makes the skirt portion of the cylinder 2 0 a part thereof 200424434 crank case. The piston 25 fitted into the cylinder hole 20a of the cylinder 20 is connected to the above-mentioned crankshaft through a rod 26, and the reciprocating motion of the piston 25 is changed to the rotation motion of the above-mentioned crankshaft. Referring to FIG. 4 at the same time, a combustion chamber 2 is formed in the cylinder head 21 on a recessed portion formed on a wall surface opposite to the cylinder hole 2 0 a and the direction A 1 of the cylinder axis L 1. There is a combustion chamber 2 7 a pair of air inlet holes 2 8 a air inlet 2 8, a pair of exhaust holes 2 7 a air outlet 2 9 that open in the combustion chamber 2 7, a spark plug 3 0 The insertion hole 31 is also provided with a pair of intake valves 3 2 that open and close a pair of intake holes 2 8 a and a pair of exhaust valves 3 3 that open and close a pair of exhaust holes 2 9 a. On the outer surface 2 1 a of the intake side of the cylinder head 21 that opens the inlet 2 8 b of the air inlet 2 8, the inlet pipe 3 4 and the inlet 2 8 of the air inlet device having the carburetor as the main fuel supply device are provided. b is connected, and an exhaust pipe 3 5 (see FIG. 1) of the exhaust device is connected to the outer side 2 1 b of the exhaust side of the cylinder head 2 1 that opens the outlet 2 9 b of the exhaust port 2 9. Further, a fuel injection valve 36 is installed adjacent to the intake port 28 at a mounting hole 2 1 c (refer to FIGS. 2, 6, and 7) formed on the intake side of the cylinder head 21 to start or accelerate the internal combustion engine E. A supplementary fuel supply device for isochronous supply of additional fuel. Among them, the intake side refers to the side where the intake valve 3 2 is provided with respect to a plane Η1 parallel to the cylinder axis L1 including the rotation centerline L 2 of the camshaft 41, and the exhaust side refers to the exhaust side provided with respect to the plane Η1 Valve 3 3 on one side. Further, the mixed gas containing the fuel 14 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 supplied from the carburetor and the fuel injection valve 36 passes the descending intake stroke of the piston 25 and passes through the intake port 28 The opened pair of intake valves 32 are sucked into the combustion chamber 27. The mixed gas sucked into the cylinder 20 is compressed by the ascending piston 2V5 during the compression stroke, and is ignited and burned by the spark plug 30, and the piston 2 5 which is lowered by the pressure of the combustion gas during the expansion stroke is rotated by the rod 26 to drive the crank ,. During the exhaust stroke, the combustion gas is discharged from the combustion chamber 2 7 to the exhaust port 2 9 through a pair of opened exhaust valves 3 3 as exhaust gas, and further passes through the exhaust pipe 3 5 and the muffler 3 7 of the exhaust device described above ( (Refer to Fig. 1) to the outside. 2, 3 and 5, each intake valve 32 and each exhaust valve 3 3 whose potential energy is increased in a closing direction by a valve spring 38 is passed through a valve operating device 40 provided in a valve chamber 39. Opening and closing, the moving valve chamber 39 is formed by a cylinder head 21 and a cylinder head cover 22. The moving valve device 40 includes a single cam shaft 41 and is rotatably supported by a pair of bearing portions 5 1 and 5 3 formed on the cylinder head 2 1; an intake swing arm 4 4 and an exhaust swing arm 4 5 The intake cam 4 2 and the exhaust cam 4 3 of a pair of control valve cams arranged on the cam shaft 41 swing; a pair of swing arm shafts 4 6 and 4 7 are supported on the cylinder head 21 and can swing respectively. Ground supports the two swing arms 4 4, 4 5. The camshaft 41 is driven to rotate at 1/2 of its rotational speed by the power of the crankshaft transmitted by a power transmission mechanism provided between the crankshafts. The transmission mechanism is composed of a driving wheel as a driving rotation body provided on the crank shaft, a cam 48 as a driven rotation body provided on the cam shaft 41, and a driving wheel and cam 4 connected to the driving wheel. The timing chain of the endless conveyor on 8 is composed of 4 9. Moreover, referring to FIGS. 6 and 7 at the same time, a pair of bearings located at 15 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 in the direction of the cylinder axis A1 is closer to the cylinder 20 than the joint surface 2 3 The parts 5 1 and 5 3 are composed of a bearing 50 composed of a ball bearing and a first bearing part 51 of one end 4 1 a of the cam shaft 41 supported in the axial direction A 2 and a ball bearing. The bearing 5 2 supports the second bearing portion 53 at the other end 4 1 b in the axial direction A 2. The first bearing portion 51 located between the insertion hole 31 and the joint surface 2 3 in the cylinder axis direction A 1 direction is formed by a part of one side wall 5 4 of the cylinder head 2 1 in the axis direction A 2, that is, the side wall 5 4 forms a part of the intermediate wall 5 4 c between the combustion chamber wall 5 7 and the insertion port 3 1 and the flange 5 4 a of the joint surface 2 3, and covers the entire end 4 The shape of the end face 4 1 a 1 of 1 a is fitted on the inner surface of the first bearing portion 51, that is, through the bottomed recess 5 5 formed on the side wall wall 4 4 of the valve chamber 3 9. The inner fitting bearing 50 supports one end portion 4 a. The first bearing portion 51 is located at a position overlapping with the insertion hole 31 when viewed in a plane (see FIGS. 5 and 7). The outer surface 5 1 a in the axial direction A 2 of the first bearing portion 51 is substantially parallel to a plane perpendicular to the rotation center line L 2 (see FIG. 5). Further, referring to Fig. 7, the first bearing portion 51 is located at a position overlapping with the spark plug 30 or the plug cap 56 on which the spark plug 30 is mounted as viewed in the axial direction A2. Further, the first bearing portion 51 is formed on the side wall 54 by a protruding portion 58 formed by the insertion hole 57 of the head bolt B1 (refer to FIG. 3) inserted on the intake side and the head bolt B3 inserted on the exhaust side. Between the protruding portions 60 formed by the insertion holes 59 (refer to FIG. 7). Referring to FIGS. 5, 6 and 8, in order to separate the moving valve chamber 39 from the transmission chamber 61, the second bearing portion 53 is isolated by Part of the wall 6 2 is composed of the partition 16 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 away from the wall 6 2 from the combustion chamber 2 7 integrally formed on the cylinder head 2 1-the side faces the cylinder head cover 2 2. It extends substantially parallel to a plane perpendicular to the rotation center line L 2, and the other end 4 1 b of the cam shaft 41 is supported by a bearing 5 2 fitted into a through hole 63 formed in the partition wall 62. The second bearing portion 53 is located in a position overlapping with the combustion chamber 27 in a plan view (see FIG. 5). In addition, the second bearing portion 5 3 is formed on the partition wall 62 with the insertion of the head bolt B 2 (see FIG. 3) inserted into the intake side. Between the protrusion portion 65 of L6 4 and the protrusion portion 67 of the insertion hole 66 where the head bolt B4 (see FIG. 3) on the exhaust side is formed. 2, 3 and 5, on the cam shaft 41, the intake cam 42 and the exhaust cam 43 are disposed between the first bearing portion 51 and the second bearing portion 53 in the axial direction A 2. The interval in the axial direction A 2 of the first bearing portion 51 and the second bearing portion 53 is substantially equal to the range D in the axial direction A 2 where the intake cam 42 and the exhaust cam 43 are provided (see FIG. 5). The exhaust cam 43 is located at a position crossing the cylinder axis L1. Further, at the other end 41b, the cam 4 8 sandwiches the second bearing portion 53 and is located on the side opposite to the intake cam and is joined to a portion inside the transmission chamber 61 where the timing chain 49 is disposed. The intake swing arm 44 is a swing swing arm having a supported portion 4 4 a formed with a through hole for inserting the swing arm shaft 46 and a drive portion 4 4 b from the supported portion 4 4 a to the cam shaft 4 1 Extended and rotatably provided on the roller 4 4 d in rolling contact with the intake cam 4 2; a pair of working portions 4 4 c extend from the supported portion 4 4 a to a pair of intake valves 32 and It can be in contact with these intake valves 32. Further, the exhaust swing arms 45 are rotating swing arms each having a supported portion 4 5 a formed with a through hole for inserting the swing arm shaft 47 and a driving portion 4 5 b from the supported portion 4 5 a to the cam The shaft 41 extends and is rotatably provided on the parent-child 4 5 d in rolling contact with the exhaust projection 17 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 wheel 4 3; a pair of working sections 4 5 c, each of which extends from the supported portion 4 a to a pair of exhaust valves 3 3 and can contact the exhaust valves 3 3. Among them, each of the rollers 44d, 45d is rotatably supported by a plurality of needle rollers 44f, 45f provided around the support shafts 44e, 45e fixed to the driving portions 44c, 45c. The restoring force of each of the swing arms 44 and 45 by a positioning spring 68 made of a compression coil spring fitted in each of the cam shafts 46 and 47 is located at a predetermined position in the axial direction A2. Therefore, each intake valve 32 and each exhaust valve 33 pass through the intake cam arm 4 4 swung by the intake cam 4 2 and the exhaust arm 45 swung by the exhaust cam 4 3 pass the intake cam 42 The exhaust cam 43 rotates in synchronization with the above-mentioned crankshaft and is opened and closed respectively at a predetermined time. The two swing arm shafts 4 6 and 4 7 are arranged in parallel with the rotation center line L 2 of the cam shaft 41, and are arranged so as to sandwich the rotation center line L 2 and the cam shaft 41 of the cam shaft 41 in plan view and are located on both sides thereof. Referring to FIGS. 6 to 8 at the same time, one end portion of each of the swing arm shafts 4 6 and 4 7 is supported on the first support portions 7 0 and 7 1 formed by a part of the intermediate wall 5 4 c, and the other end is supported on the cylinder axis. A part of the partition wall 62 located between the second bearing portion 53 and the joint surface 23 in the direction A1 is on the second support portion 7 2, 7 3. Therefore, the end fitting holes of the swing arm shafts 4 6 and 47 are formed in the support portions 7 1 to 7 3 at positions closer to the cylinder 20 than the flange 5 4 b of the joint surface 2 3 in the cylinder axis direction A1. 74 ~ 77. In addition, the pair of first support portions 70 and 71 is located at a position sandwiching the first bearing portion 51 in plan view (see FIGS. 6 and 7). Referring to FIGS. 4 to 7, the front end of the Mars plug 3 0 is formed with a male screw 18 312 screwed into the male screw 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 The female screw portion 3 1 a of the pattern 3 0 a is inserted. The hole 3 1 has an opening portion 3 1 b opened on the outer side of the combustion chamber name and a combustion-side opening portion 3 1 which is located on the inner surface of the combustion chamber 5 4 a and is opened substantially centrally on the top surface of the combustion chamber 27. c. Therefore, in a state where the male screw portion 30a is not exposed from the combustion chamber, the spark plug 30 is mounted on the combustion chamber wall 54a, and the electrode portion 30c protruding from the groove portion 30a is adjacent to the approximate portion of the combustion chamber 27. Therefore, the center electrode 3 0 c 1 and the side electrode 3 0 c 2 are located at positions crossing the vapor line L1. The insertion hole 31 is formed at a position crossing the plane H1 (FIG. 7), and its opening portion 31 c intersects the cylinder axis L1. Moreover, as shown by the female, the insertion hole 31 is inclined from the side with respect to the cylinder axis L1 on the side opposite to the position of the first bearing portion 53, and the Mars plug 30 and the plug cover 5 6 are coaxial with the plug portion 5 6 a is also inclined at the same angle as the insertion hole 31. In the state where the spark plug 30 is inserted into the cylinder head 21, the spark plug 30 extending from the combustion chamber 5 to the cylinder head cover 22 is arranged in the recess 78. The recess is composed of three The side wall 54 surrounds two protrusions 5 8 and 60 which are formed as a part of the side wall 5 4 which is a direction A3 (a direction perpendicular to the plane of rotation perpendicular to the rotation center line L2) perpendicular to the plane and is the direction A2. The intermediate wall 54c is a part of the upper side wall 54 in the upward direction. Furthermore, a high-voltage ignition wire connected to the ignition coil is connected to the fire 30, so the plug cover 56 mounted on the spark plug 30 is located in the recess between the two first support portions 70 and 71. Referring to FIGS. 3 and 5, the other end 41 b of the camshaft 41 is provided with a cooling water pump as an auxiliary device in the direction of the direction A 2 8 0 312 / Invention Specification (Supplement) / 93-06 / 93108657 t 54a Chamber wall firing chamber 27 Inner screw center cylinder axis Refer to Figure 3 Figure 2 Second axis and fire ○ 54a The two H1 vertical axes surround the star plug 78 paraxial, its 19 200424434 center line and the rotation of the cam shaft 41 The center line L 2 is the same. The cooling water pump 80 mounted on the cylinder head 21 has a pump body 81 fixed to the other side wall 7 9 provided in the axial direction A 2 of the cylinder head 21 1 in the transmission chamber 60 and a pump cover 82 located at The outside of the cylinder head 21 is combined with the pump body 81 to form a pump chamber 8 3 between the pump bodies 81; a support shaft 84 is supported between the pump body 81 and the pump cover 82; and a turbine 85 is arranged in the pump body In 81, it is rotatably supported on a support shaft 84, and has a plurality of blades 85b ° located in the pump chamber 83. The cooling water pump 80 is driven by the camshaft 41 by a drive mechanism provided between it and the camshaft 41. The above driving mechanism is composed of a driving rotating body 86, which is combined with the cam 48 through the protruding portion B5 on the end surface 41bl of the portion of the cam shaft 41 that is adjacent to the transmission chamber 61 at the other end 41b; and as the turbine 8 5 — Part of the body part 8 5 a. A driving rotor 86 provided in a bowl-shaped cam chain provided near the cam shaft 41 inside the timing chain 49 is provided with a ring-shaped permanent magnet 86c fixed to a peripheral portion surrounding the pump body 81, and a main body portion 85a of the turbine 85 The ring-shaped permanent magnet 8 5 c is fixed at a position radially opposed to the permanent magnet 86 c. Therefore, if the driving rotating body 86 rotates together with the camshaft, the turbine 85 which is magnetically coupled to the driving rotating body 86 through the permanent magnets 86c and 85c rotates, and the inflowing cooling water is sent to the pump chamber 83. The pump cover 82 is provided with a thermostat 90 that controls the flow of cooling water in the cylinder 20 and the cylinder head 21 in accordance with the temperature of the cooling water. The thermostat 90 has a valve body 92 that opens and closes an inflow passage 93, and the inflow passage 93 is formed on the pump cover 82 by driving the pump cover 82 with paraffin 91 that expands or contracts according to the temperature of the cooling water. 20 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 As shown in Figure 5, when the internal combustion engine E is warmed up, the valve body 9 2 ® circuit 93 prevents cooling from the cooler (not shown) The water pump 80 can pressurize the inflowing cooling water through the cooling pump 80. After the cylinder 20 and the cylinder head 21 are looped, the valve body 92 opens the inflow passage 93 and the above-mentioned cold becomes low temperature. The cooling water is looped on the following path, is pressed into the water pump 80, and then the above-mentioned cooler after the cylinder and the cylinder head 21 are cooled. Referring to FIGS. 2, 3 and 6, a fuel injection horse is installed in a mounting hole 2 1 c of the cylinder head 21 formed on one side 6 9 of the cylinder head 2 1 as the vertical direction A 3 on the side. On the intake side of the cylinder head cover at the upper part of the cylinder head cover 22, a venting chamber 100 provided in a communication path R of the crank chamber 39 is provided adjacent to the transmission chamber 61 above. The ventilation passage R is formed by the ventilation passage 1 2 0 and the cylinder-side ventilation passage (the cylinder-side passage is not shown in the figure) formed on the cylinder head 21 and communicates with the ventilation | It communicates with the above-mentioned crank chamber. A through-air passage 120 extending along the cylinder axis direction A 1 adjacent to the upper part of the movable chamber 3 1 is composed of the opening 1 on the joint surface 23 and the upper chamber 1 0 0 -side. 20 a; a through-hole, having an opening on the joint surface 21 h and an opening 1 2 0 b on the cylinder 20 side that communicates with the cylinder side (see FIG. 4). Side 6 9 a along; 312 / Invention Specification (Supplement) / 93-06 / 93108657 ^ Closed inflow water flow into cooling from bypass 94. Heat is released at the end of the warmer, flows into the cooling, and returns To the intake side, the upper side 3 3 6 of each side wall is composed of the opening and the upper side of the opening and the upper side of the upper side of the opening. One end of the cylinder 2 road is connected to the side 6 9 a 21 200424434 The extended fuel injection valve 3 6 is arranged in a plan view and through The air chamber 100 is located at an end 36a connected to the fuel supply pipe at the position of the flange 69b. Further, referring to Figs. 2 and 7, the fire 36 is located at a position closer to the venting chamber 100 or the cylinder 20 in the cylinder axis direction A1, and is located at a position coincident with this when viewed from the axial direction. Referring to FIG. 2, FIG. 9, FIG. 10, and FIG. 12 ′, with respect to the plane on the steam A 1 and the joint surface 2 3 in the same plane, the ventilation chamber 1 0 0 located on only one side is composed of the following: Chamber 1 The head part 2 of the cylinder head 2 is composed of the upper part of the ventilation chamber forming part 103. The second chamber 102 is formed by a cap-shaped lid 104 covering the ventilation chamber forming part 103 of the first chamber 101. . The ventilation chamber forming portion 103 has a flat bottom wall 1 0 3 a, and on the same plane as the bonding surface 23 and the bonding surface 22, the upper surface 1 0 3 b having a part of the surface 2 2 a is described above. Bottom opening 1 2 0 a. Therefore, a sealing groove 1 0 3 c of An 2 4 is formed on the upper side 10 3 b to seal between the joint surfaces 2 3 of the upper edge 1 of the opening 1 2 0 a. The bottom wall 10 3 a has a shape 105 and an oil return passage 106 formed by any through hole, so that the ventilation passage 120 communicates with the first chamber 101, and the oil returns to a position below the inlet passage 105. At the same time, according to FIG. 3 and FIG. 6 ′, an isolation ventilation passage 1 2 0 and a moving valve chamber 39 are formed on the cylinder 21, and an end surface 10 7 a on the same plane as the transmission chamber 6 1 and the joint surface 23 is formed. Every 312 / Invention Specification (Supplement) / 93-06 / 93108657 The overlapping position is near the upper wall 6 9 Natural gas injection valve inlet hole 28a L Air passage 1 2 0 Cylinder head 2 2 01 The depression is air-tightly installed on the bottom wall 1 0 3 a and has a combination of t 1 0 3 a covering and sealing member 20 a1 and is provided with an entrance path [the entrance road 1 0 5 road 1 0 6 is located off the wall 1 0 7, It also has a protruding part 107b from the wall 10 07 22 200424434. The protruding part 107b is a part connecting the partition wall 62 and the partition wall 107 in the up-and-down direction when viewed from above, and moves toward the valve along the partition wall 62. Chamber 3 9 —The side protrudes downward. A groove 108 communicating with the oil return passage 106 in the ventilation passage 102 is formed in the protruding portion 107b. As shown in FIG. 9, the groove 108 extends below the lower edge 10 3 a of the bottom wall 10 3 a so that its lowermost portion does not cover the bottom wall 1 0 3 a, and the outlet 1 1 0 formed thereby It communicates with the moving valve chamber 3 9 and the transmission chamber 6 1. Therefore, a communication path 10 9 is formed through the groove 108 to communicate the ventilation chamber 100 with the valve chamber 39 and the transmission chamber 61. On the one hand, the cover 104 is sealed to the joint surface 1 0 3 d formed on the ventilation chamber forming portion 10 3 by the sealing member 1 1 1 and is connected to the ventilation chamber forming portion 1 by three bolts B 6. 0 3 is fixed to the cylinder head 21. Therefore, a sealing groove 1 0 4 c for mounting a sealing member 1 1 1 is formed on the joint surface 10 3 d of the cover 104 and the joint surface 10 4 d, and a through hole is formed on the flange of the cover 104 1 0 4 e, penetrating a through hole 1 0 3 e formed in the vent chamber forming portion 103, and passing each bolt B6 screwed into a screw hole 2 1 e formed in the flange 6 9 of the cylinder head 21 . Further, the cover 104 is provided with an outlet passage 112 in the ventilating chamber 100 so that a plurality of protruding portions 10 3 k, 1 0 3 丨 n, 1 0 4 k, and 1 0 4 丨 n described later are sandwiched therebetween. And the entrance road 105. The outlet path 112 is formed here by a pipe joint 11 13 which is pressed into the cover 104. The pipe joint 113 is connected with a circulation pipe (not shown), which forms a circulation passage that communicates with the intake passage of the air intake device. The ventilating chamber 100 and the above-mentioned intake passage are in communication with the above-mentioned circulation passage through an outlet passage 12. Referring to FIG. 9, FIG. 11, and FIG. 12, in order to separate oil from a leaky gas containing an oil component flowing into the ventilation chamber 1 0023 3 丨 2 / Invention Specification (Supplement) / 93-06 / 93108657 200424434, A plurality of protruding walls 103k, 103m, 103n, 104k, 104m, 104η are formed on the ventilation chamber forming portion 103 and the cover 1 ο 4. These protruding walls have mating portions 103kl, 103ml, 103ml, 103n, 104kl, 104ml, 104nl and divide the ventilation chamber into a labyrinth. Therefore, the air leak flowing from the inlet road 105 into the ventilation chamber 100 is colliding with these protruding walls 103k, 103m, 103n, 104k, 104m, 104η in the ventilation chamber 100, while going to the outlet road 1 1 2 flow 'promotes oil separation. Therefore, the gas leak containing the oil for lubricating the internal combustion engine E passes through the ventilation chamber 120 from the crank chamber, and then mainly flows into the ventilation chamber 100 from the inlet path 105. The leaked air flowing into the ventilating chamber 100 collided with the protruding walls 103k, 103m, 103n, 104k, 104m, 104n while flowing in the ventilating chamber 100 divided into a labyrinth region, and the oil was separated. The leaked oil that has been separated is sucked out by the negative pressure of the intake passage, flows into the intake passage through the outlet passage 1 12 and the circulation passage, and further flows into the combustion chamber 27 to be burned. Then, the separated oil flows from the oil return path 106 into the communication path 109, and the flow-down communication path 109 flows into the transmission chamber 61, and is supplied to the moving valve device 40 or the above-mentioned transmission mechanism for lubrication. The operation and effect of the embodiment configured as described above will be described below. An insertion hole 31 for inserting a spark plug 30 is formed in the cylinder head 21, and the spark plug 30 has an electrode portion 60c near a substantially central position of the combustion chamber 27. On this cylinder head 21, the first bearing portion 51, which supports one end 4a of the single camshaft 41, is located at a position where the plan view coincides with the insertion hole 31, and is located in the cylinder axis direction A1 direction Between the insertion port 31 and the joint surface 23, and covering one end 24 constituted by the side wall 5 4 of the cylinder head 21 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434 41a, from the axial direction A2: Mars plug 30 or 56 is overlapped with the first bearing part 51. There is no name 2 3 in the first bearing part 51. Therefore, there is no need to provide a sealing area for ensuring tightness, and it is sufficient to control the slave axis direction A. Seen in the 2 direction, the amount of the Martian plug 3 0 or the plug cover 5 6 placed at the first bearing position 51 is superimposed. Because the side insertion hole 3 1 can be reduced, the tilt of the Mars plug 3 relative to the cylinder axis L1 is reduced. 0 The inclination of the cylinder head 5 6, because the spark plug 3 0 in the insertion hole 31 has no space 3 1 d (see FIG. 5), it is possible to suppress the increase in the volume of the combustion chamber, the output of the internal combustion engine, and the electrode portion 3 0 c Insertion into the hole 31 can improve the ignition performance. In addition, the first bearing portion 51 does not need to increase the support rigidity of the camshaft 41 and the thickness of the three side walls 54 in the case of a bearing portion or the like, so that the internal combustion engine can be made lighter. The intake valve 3 2 and the exhaust valve 3 3 can be oscillated and supported on the swing arm shafts 4 6 and 4 7 respectively by the inlet wheel 4 2 and the exhaust cam. 4 3 is opened and closed, a pair of swing arm shafts 4 6 and 4 7 are located between the first bearing portion 51 and the joint surface 2 3 in the cylinder direction A 1, and are arranged to sandwich the rotation center line L 2 of the cam shaft 4 1, It is located on both sides, and one end of the swing arm shaft 4 6 and 4 7 is supported on a pair of support portions 70 and 71 formed by the side wall 54. These two support portions 70 and 71 are located on the clamp bearing portion 5 1 in plan view. In the position, there is no surface 2 3 on each of the support portions 70 to 73, so there is no need to provide a sealing area to ensure tightness, and the two first bearing portions 70 and 71 can be plugged into Mars 30 or the center. The amount of cover 5 6 can be reduced as viewed from the side. The insertion hole 3 1 is inclined with respect to the cylinder shaft | that is, the inclination of the Mars plug 30 and the cylinder head 56, although the Mars plug 312 / Invention Specification (Supplement) / 93- 06/93108657 The surface of the plug can be set up to see the surface and increase the steam occupation. The cutting shaft f is added to the air convex axis. A pair of first first combination controls extend L L1 30 25 2 00424434 or the inclination of the plug cover 56 is reduced, but it does not interfere with the two first support portions 70, 71 of the pair of swing arm shafts 4, 6, 4, 7 and makes the two swing arm shafts 4, 6, 4, 7 is close to the camshaft 41, and the distance between the shafts can be shortened. Therefore, when viewed in a direction A 3 perpendicular to the rotation center line L 2, the cylinder head 21 can be miniaturized. The intake rocker arm 4 4 and the exhaust rocker arm 45 are rolling arms having rollers 4 4 d and 4 5 d respectively in contact with the intake cam 4 2 and the exhaust cam 4 3. The second bearing portion 5 3 supports On the other end portion 41 b of the camshaft 41, an intake cam 4 2 and an exhaust cam 43 are provided between the first bearing portion 51 and the second bearing portion 53, and the first bearing portion 51 and the first bearing portion 51 The interval between the two bearing portions 5 3 in the axial direction A 2 is substantially equal to the axial range A 2 provided by the intake cam 4 2 and the exhaust cam 4 3. Each cam 4 2, 4 3 and each swing arm 4 are provided. The contact of 4, 4 and 5 becomes rolling contact, and the friction coefficient becomes smaller, so even if the contact pressure of each cam 4 2, 4 3 and each of the swing arms 4 4, 4 5 increases, the intake cam 4 2, the exhaust cam 4 3, The abrasion resistance of the intake swing arm 44 and the exhaust swing arm 45 does not decrease, so the widths of the intake cam 42 and the exhaust cam 43 in the axial direction A2 can be reduced, and both ends of the cam shaft 41 can be supported. The interval between the first and second bearing portions 5 1, 5 3 of 4 1 a, 4 1 b is reduced in response to the range D set by the intake cam 4 2 and the exhaust cam 4 3, so that the cam shaft can be reduced. 41 The length of the cylinder head 21 can be made compact in the axial direction A 2 direction. Therefore, even when a cooling water pump 80 is provided near the axial direction A 2 on the other end portion 4 1 b of the cam shaft 41, it is possible to prevent the cylinder head 21 of the internal combustion engine E in the axial direction A 2 from being partially caused. The internal combustion engine E becomes larger. The upper wall 6 9 of the cylinder head 2 1 is provided with a mounting hole 2 1 c for mounting the fuel injection valve 3 6 and a communication port 26 312 / Invention Specification (Supplementary Note) communicating with the ventilation chamber 1 0 0 formed in the cylinder head cover 2 2. ) / 93-06 / 93108657 200424434 Air passage 1 2 0, fuel injection valve 36 6 in the cylinder axis direction A 1 is closer to the air inlet 100 of the air chamber 100 than the air inlet 28 of the air inlet 28, and it is located in the air passage A2 in the axial direction A2 1 2 0 overlap position, at the cylinder head 2] The fuel injection valve 3 6 does not affect the vent passage 1 2 0 and the large-capacity vent chamber. Therefore, it is possible to provide a close to the camshaft 41 in the vertical direction A3 (or vertical direction). At the position of turning the center line L 2, the injection valve 36 can be compactly arranged in the vertical direction A3 (or in the up-down direction) on the steam 21, and the periphery of the cylinder 21 can be compact. Therefore, from the axial direction (or the above) The direction of the crankshaft's rotation center line) can reduce the inclination of the injection valve 36 with respect to the cylinder axis L1, and can make the fuel of the discharge injection valve 36 inject toward the intake hole 2 8a, so that the fuel injection centerline Further along the cylinder axis direction A 1, it is possible to reduce the blowing to the exhaust port The output of the internal combustion engine can be increased. Therefore, the periphery of the cylinder head 21 can be made compact, so that the cylinder head 21 can be arranged in a relatively narrow space behind the pedal 15 c and under the storage box 12. The venting chamber 1 0 0 is vented as a part of the cylinder head cover 2 2] The forming part 1 0 3 and the cover 1 0 4 installed at the venting chamber forming part 1 0 3 form the air chamber 1 0 0 without passing through the miniaturized cylinder head The valve chamber 3 9 formed by 2 1 is provided with a limit fil of the valve device 40, and the volume of the valve chamber 39 is increased without increasing the size of the cylinder head 2 1 and the cylinder head cover 2 2. In addition, the flat portion is located at a position coincident with the venting chamber 100, and the end portion 3 a can interact with the fuel injection valve 36 at a position close to the flange 6 9 b to form a large-volume venting chamber 100 Can improve the content of leaks! Separation function, and because no ventilation is formed in the cylinder head 21 | 312 / Invention Specification (Supplement) / 93-06 / 93108657 in the direction of ventilation. In the middle, 100 is placed in the cylinder head to fire A 2 fuel spontaneously. 29. The surface is more r-shaped, and the inside and the steam can avoid the oil 27 200424434 1 0 0, so the cylinder head 21 can be miniaturized. Next, a description will be given of a modified configuration of the embodiment which is a part of the above-mentioned example. The internal combustion engine E has a pair of intake valves 32 and a pair of exhaust valves 3 3, but either one of the intake valve and the exhaust valve is a pair of valves, and the other is a single valve. A structure in which either one of the exhaust valve is a valve may be used. In the above embodiment, the fuel supply device is constituted by the carburetor and the fuel injection valve 36, but may be constituted only by the fuel injection valve mounted on the cylinder head 21 near the intake port 28. Moreover, although the internal combustion engine E is used in a vehicle in the above embodiment, it may be used in a device other than the vehicle. [Brief Description of the Drawings] Fig. 1 shows an embodiment of the present invention and is a left side view of a two-wheeled locomotive equipped with an internal combustion engine having a cylinder head according to the present invention. FIG. 2 is a cross-sectional view of a main part of the internal combustion engine shown in FIG. 1, a cross-sectional view of a cylinder head taken along line II a-II a in FIG. 3, and a cam shaft and a swing arm along II in FIG. 3. b-II Sectional drawing on line b. FIG. 3 is a cross-sectional view taken along the line I I I _ I I I in FIG. 2. FIG. 4 is a cross-sectional view taken along the line I V-IV in FIG. 2. Fig. 5 is a sectional view taken along the line V-V in Fig. 3. FIG. 6 is a perspective view of a cylinder head of the internal combustion engine in FIG. 1. FIG. 7 is a cross-sectional view of the cylinder head of FIG. 5 taken along the line V I I-V I I. FIG. 8 is a cross-sectional view taken along the line V I I I-V I I I in FIG. 7. Fig. 9 is a sectional view of the vent chamber forming portion of the cylinder head cover shown in Fig. 2 taken along line I X-I X 28 312 / Invention Specification (Supplement) / 93-06 / 93108657 200424434. FIG. 10 is a sectional view of the cylinder head cover in FIG. 2. FIG. FIG. 11 is a cross-sectional view taken along the line XI_XI in FIG. 9 and FIG. 12 is a ventilation chamber formed in FIG. 2. (Description of element symbols) A cross-sectional view of the ventilating chamber forming portion taken along the line X-X. Section of cover X I I-X I I
1 前 車架 2 後 車架 3 前 叉 4 臂 5 前 緩衝器 6 前 輪 7 手 柄 8 枢 軸 9 後 緩衝器 10 後 輪 11 頭 盔 12 收 置箱 13 擋 板 14 燃 料箱 15 車 體護罩 20 汽 缸 2 1 汽 缸頭 312/發明說明書(補件)/93-06/93108657 29 200424434 22 汽 缸 頭 蓋 23 結 合 面 24 密 封 構 件 25 活 塞 26 桿 27 燃 燒 室 28 進 氣 口 29 排 氣 口 30 火 星 塞 30a 陽 螺 紋 部 30c 電 極 部 30cl 中 心 電 極 30c2 側 面 電 極 31 插 入 孔 31a 陰 螺 紋 部 31b 開 π 部 32 進 氣 闊 33 排 氣 閥 34 進 氣 管 35 排 氣 管 36 燃 料 喷 射閥 37 消 聲 器 38 閥 彈 簧 39 動 閥 室 312/發明說明書(補件)/93-06/931086571 Front frame 2 Rear frame 3 Front fork 4 Arm 5 Front bumper 6 Front wheel 7 Handle 8 Pivot 9 Rear bumper 10 Rear wheel 11 Helmet 12 Storage box 13 Baffle 14 Fuel tank 15 Body cover 20 Cylinder 2 1 Cylinder head 312 / Invention manual (Supplement) / 93-06 / 93108657 29 200424434 22 Cylinder head cover 23 Joint face 24 Sealing member 25 Piston 26 Rod 27 Combustion chamber 28 Air inlet 29 Exhaust port 30 Mars plug 30a Male thread 30c electrode part 30cl center electrode 30c2 side electrode 31 insertion hole 31a female threaded part 31b open π part 32 intake wide 33 exhaust valve 34 intake pipe 35 exhaust pipe 36 fuel injection valve 37 muffler 38 valve spring 39 moving valve chamber 312 / Invention Specification (Supplement) / 93-06 / 93108657
30 200424434 40 動 閥 裝 置 41 凸 輪 轴 41a 一 個 端 部 41al 端 面 41b 另 一 個 端 部 41 bl 端 面 42 進 氣 凸 輪 43 排 氣 凸 輪 44 進 氣 擺 臂 44b 驅 動 部 44d 輥 子 44e 支 承 軸 44f 滾 針 45 排 氣 擺 臂 45b 驅 動 部 45d 輥 子 45e 支 承 軸 45f 滾 針 46 ^ 47 擺 臂 軸 48 凸 輪 鏈 49 定 時 鏈 50 ' 52 軸 承 51 第 一 軸 承 部 53 第 二 軸 承 部 312/發明說明書(補件)/93-06/9310865730 200424434 40 Actuating valve device 41 Camshaft 41a One end 41al End 41b End 41b Another end 41 bl End 42 Intake cam 43 Exhaust cam 44 Intake swing arm 44b Drive 44d Roller 44e Support shaft 44f Needle 45 Exhaust Swing arm 45b Drive part 45d Roller 45e Support shaft 45f Needle 46 ^ 47 Swing arm shaft 48 Cam chain 49 Timing chain 50 '52 Bearing 51 First bearing section 53 Second bearing section 312 / Invention Specification (Supplement) / 93- 06/93108657
31 200424434 54 54a、 54b 54c 55 5 6 57 ^ 5 9 58 > 60 61 62 63 64、66 65 ^ 6 7 69 70、71 72 ^ 7 3 74 〜77 78 79 80 81 82 83 84 8531 200424434 54 54a, 54b 54c 55 5 6 57 ^ 5 9 58 > 60 61 62 63 64, 66 65 ^ 6 7 69 70, 71 72 ^ 7 3 74 ~ 77 78 79 80 81 82 83 84 85
側 壁 法 蘭 中 間 壁 凹 部 塞 蓋 插 入 孔 突 起 部 傳 動 室 隔 離 壁 通 孔 插 入 孔 突 起 部 上 壁 第 一 支 承 部 第 二 支 承 部 孔 凹 部 側 壁 冷 卻 水 泵 泵 體 泵 蓋 泵 室 支 承 軸 散 熱 器 312/發明說明書(補件)/93-06/93108657 32 200424434 85a 本 體 部 85c 永 久 磁 鐵 86 驅 動 轉 動 體 86c 永 久 磁 鐵 90 恒 溫 器 9 1 石 蠟 92 閥 體 93 流 入 通 路 94 旁 路 100 通 氣 室 101 、 102 室 103 通 氣 室 形 成 104 蓋 105 入 口 路 106 油 返 回 通 路 1 07 隔 壁 1 08 溝 1 09 連 通 路 110 出 π 111 密 封 構 件 112 出 口 路 113 管 接 頭 120 通 氣 通 路 V 二 輪 機 車 312/發明說明書(補件)/93-06/93108657 300424434Side wall flange middle wall recessed plug insertion hole protrusion transmission room partition wall through hole insertion hole protrusion upper wall first support portion second support portion hole recessed side wall cooling water pump pump body pump cover pump chamber support shaft radiator 312 / invention Instructions (Supplement) / 93-06 / 93108657 32 200424434 85a Body 85c Permanent magnet 86 Drive rotor 86c Permanent magnet 90 Thermostat 9 1 Paraffin 92 Valve body 93 Inflow path 94 Bypass 100 Ventilation chamber 101, 102 Room 103 Ventilation Chamber formation 104 cover 105 inlet path 106 oil return path 1 07 next door 1 08 trench 1 09 communication path 110 exit π 111 seal member 112 outlet path 113 pipe joint 120 ventilation path V two-wheeled locomotive 312 / Invention Specification (Supplement) / 93- 06/93108657 300424434
F 車 體 框 架 P 動 力 單 元 E 内 燃 機 Μ 白 動 變 速 器 Β1〜 Β4 頭 螺 栓 Β5、 Β6 螺 栓 L1 汽 缸 軸 線 L2 轉 動 中 心 線 Α1 汽 缸 軸 線 方向 Α2 軸 方 向 A3 垂 直 方 向 Η1 平 面 D 範 圍 R 通 氣 通 路 312/發明說明書(補件)/93-06/93108657 34F Body frame P Power unit E Internal combustion engine M White-moving transmission B1 ~ B4 Head bolts B5, B6 Bolt L1 Cylinder axis L2 Rotation center line A1 Cylinder axis direction A2 Axial direction A3 Vertical direction Η1 Plane D Range R Ventilation passage 312 / Invention manual (Supplement) / 93-06 / 93108657 34