TW201418569A - Air-cooling type internal combustion engine and saddled vehicle having the same - Google Patents
Air-cooling type internal combustion engine and saddled vehicle having the same Download PDFInfo
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- TW201418569A TW201418569A TW102135544A TW102135544A TW201418569A TW 201418569 A TW201418569 A TW 201418569A TW 102135544 A TW102135544 A TW 102135544A TW 102135544 A TW102135544 A TW 102135544A TW 201418569 A TW201418569 A TW 201418569A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F1/26—Cylinder heads having cooling means
- F02F1/28—Cylinder heads having cooling means for air cooling
- F02F1/30—Finned cylinder heads
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F1/26—Cylinder heads having cooling means
- F02F1/28—Cylinder heads having cooling means for air cooling
- F02F1/30—Finned cylinder heads
- F02F1/32—Finned cylinder heads the cylinder heads being of overhead valve type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F1/26—Cylinder heads having cooling means
- F02F1/28—Cylinder heads having cooling means for air cooling
- F02F1/30—Finned cylinder heads
- F02F1/34—Finned cylinder heads with means for directing or distributing cooling medium
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- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Cylinder Crankcases Of Internal Combustion Engines (AREA)
Abstract
Description
本發明關於一種內燃機,尤其是關於一種氣冷式內燃機。又,本發明亦關於一種具備氣冷式內燃機之跨坐型車輛。 The present invention relates to an internal combustion engine, and more particularly to an air-cooled internal combustion engine. Further, the present invention relates to a straddle type vehicle having an air-cooled internal combustion engine.
近年來,為了提高燃油效率(低油耗),強烈要求以更高的壓縮比來運轉內燃機。但是,若提高壓縮比,則活塞的上死點(top dead center,TDC)附近+的溫度容易上升,而容易產生爆震(knocking)。 In recent years, in order to improve fuel efficiency (low fuel consumption), it is strongly required to operate an internal combustion engine with a higher compression ratio. However, if the compression ratio is increased, the temperature of the vicinity of the top dead center (TDC) of the piston is likely to rise, and knocking is likely to occur.
為了防止此種爆震的產生,需要提高缸頭(cylinder head)的冷卻性。通常,在氣冷式的內燃機中,相較於水冷式的內燃機,由於存在冷卻性較低之傾向,因此,尤其是在氣冷式的內燃機中,可謂要求進一步提高缸頭的冷卻性。 In order to prevent such knocking, it is necessary to improve the cooling performance of the cylinder head. In general, an air-cooled internal combustion engine has a tendency to have lower cooling performance than a water-cooled internal combustion engine. Therefore, particularly in an air-cooled internal combustion engine, it is required to further improve the cooling performance of the cylinder head.
因此,一般想到利用壓鑄(模鑄,die casting)來將缸頭加以成形,藉此使冷卻片(散熱片,cooling fin)變薄並設置多個冷卻片。於專利文獻1中,揭示一種利用壓鑄來成形具有冷卻片之缸頭的技術。又,於專利文獻1所揭示之技術中,當藉由壓鑄來成形缸頭時,藉由對預先準備的襯套(liner)進行 澆鑄,而形成吸氣通道和排氣通道等。也就是說,缸頭包含分體(分離)的構件(吸氣通道形成用襯套和排氣通道形成用襯套)。 Therefore, it is generally conceivable to mold a cylinder head by die casting, thereby thinning a cooling fin (cooling fin) and providing a plurality of cooling fins. Patent Document 1 discloses a technique of forming a cylinder head having a cooling fin by die casting. Further, in the technique disclosed in Patent Document 1, when the cylinder head is formed by die casting, by performing a liner prepared in advance Casting to form an intake passage and an exhaust passage. That is, the cylinder head includes a separate (separate) member (a suction passage forming bushing and an exhaust passage forming bush).
專利文獻1:日本特開2004-116464號公報 Patent Document 1: Japanese Patent Laid-Open Publication No. 2004-116464
然而,於專利文獻1所揭示之缸頭中,並未形成用以使冷卻空氣通過之冷卻空氣通道。因此,即使將專利文獻1的缸頭用於氣冷式的內燃機中,亦可能無法獲得充分的冷卻性。又,由於利用壓鑄難以形成底切(undercut)形狀(當自金屬模具取出成形品時,利用通常的開模難以脫模之形狀),因此,難以在藉由壓鑄所成形的缸頭,設置充分的截面積的冷卻空氣通道。 However, in the cylinder head disclosed in Patent Document 1, the cooling air passage for passing the cooling air is not formed. Therefore, even if the cylinder head of Patent Document 1 is used in an air-cooled internal combustion engine, sufficient cooling performance may not be obtained. Moreover, since it is difficult to form an undercut shape by die casting (a shape which is difficult to demold by a normal mold opening when a molded article is taken out from a metal mold), it is difficult to provide sufficient shape of a cylinder head formed by die casting. The cross-sectional area of the cooling air passage.
並且,當如專利文獻1般地澆鑄襯套時,壓鑄時襯套可能會產生位置偏移而導致吸氣通道和排氣通道產生位置偏移,結果可能會導致內燃機的性能降低。 Further, when the bushing is cast as in Patent Document 1, the bushing may be displaced at the time of die casting to cause a positional shift of the intake passage and the exhaust passage, with the result that the performance of the internal combustion engine may be degraded.
因此,較佳為壓鑄時在不澆鑄襯套的狀態下,形成吸氣通道和排氣通道,但因此需要使用模心(core)。然而,此時,模心亦可能會產生位置偏移,因而內燃機的性能可能降低。 Therefore, it is preferable to form the intake passage and the exhaust passage in the state where the bushing is not cast at the time of die casting, but it is therefore necessary to use a core. However, at this time, the center of the mold may also be displaced, and the performance of the internal combustion engine may be degraded.
本發明是鑒於上述問題而完成,其目的在於提供一種氣冷式內燃機,該氣冷式內燃機具備缸頭本體,該缸頭本 體具有擁有充分的截面積之冷卻空氣通道,且可藉由壓鑄較合適地成形。 The present invention has been made in view of the above problems, and an object thereof is to provide an air-cooled internal combustion engine including a cylinder head body, the cylinder head The body has a cooling air passage having a sufficient cross-sectional area and can be suitably shaped by die casting.
依據本發明的氣冷式內燃機,具備缸頭本體,該缸頭本體具有:複數個冷卻片;凸輪室壁,其規定凸輪室;燃燒室壁,其規定燃燒室;吸氣通道,其用以對前述燃燒室進行吸氣;排氣通道,其用以自前述燃燒室進行排氣;及,冷卻空氣通道,其用以使冷卻空氣通過前述凸輪室壁和前述燃燒室壁之間;並且,前述缸頭本體是藉由壓鑄而由鋁合金一體成形;前述缸頭本體,進而具有容置凸輪鏈之凸輪鏈室;當自氣缸軸線方向來觀察時,前述排氣通道是以隨著自入口側朝向出口側而遠離前述凸輪鏈室之方式延伸,且以前述排氣通道的軸線成直線狀之方式而形成。 An air-cooled internal combustion engine according to the present invention includes a cylinder head body having: a plurality of cooling fins; a cam chamber wall defining a cam chamber; a combustion chamber wall defining a combustion chamber; and an intake passage for Suctioning the combustion chamber; exhausting passage for exhausting from the combustion chamber; and cooling air passage for passing cooling air between the cam chamber wall and the combustion chamber wall; The cylinder head body is integrally formed from an aluminum alloy by die casting; the cylinder head body further has a cam chain chamber for accommodating a cam chain; when viewed from a cylinder axis direction, the exhaust passage is followed by a self-entry The side extends toward the outlet side away from the cam chain chamber, and is formed in such a manner that the axis of the exhaust passage is linear.
於某一實施形態中,前述複數個冷卻片,包含自用以規定前述排氣通道之排氣通道壁延伸之冷卻片。 In one embodiment, the plurality of cooling fins comprise a cooling fin extending from a wall of the exhaust passage defining the exhaust passage.
於某一實施形態中,前述排氣通道的內周面的表面粗糙度Rz為30μm以下。 In one embodiment, the inner circumferential surface of the exhaust passage has a surface roughness Rz of 30 μm or less.
於某一實施形態中,前述缸頭本體,進而具有複數個螺栓孔,該複數個螺栓孔分別插通有帶頭螺栓(head bolt);前述複數個螺栓孔中的一個螺栓孔,設置於前述排氣通道與前述凸輪鏈室之間;前述冷卻空氣通道的一部分位於前述一個螺栓孔與前述排氣通道之間。 In one embodiment, the cylinder head body further has a plurality of bolt holes, and the plurality of bolt holes are respectively inserted with a head bolt; and one of the plurality of bolt holes is disposed in the row A gas passage is interposed between the cam chain chamber and a portion of the cooling air passage between the one bolt hole and the exhaust passage.
於某一實施形態中,前述複數個冷卻片是以下述方式而設置:相對於前述燃燒室壁的頂部而位於前述燃燒室側 之冷卻片的面積的合計,大於相對於前述燃燒室壁的頂部而位於與前述燃燒室為相反側之冷卻片的面積的合計。 In one embodiment, the plurality of cooling fins are disposed in such a manner as to be located on the combustion chamber side with respect to the top of the combustion chamber wall. The total area of the cooling fins is larger than the total area of the cooling fins on the opposite side of the combustion chamber with respect to the top of the combustion chamber wall.
於某一實施形態中,前述複數個冷卻片是以下述方式而設置:當自相對於氣缸軸線與前述凸輪鏈室為相反側來觀察時,相對於前述燃燒室壁的頂部而位於前述燃燒室側之冷卻片的氣缸軸線側的端部,比相對於前述燃燒室壁的頂部而位於與前述燃燒室為相反側之冷卻片的氣缸軸線側的端部,更靠近氣缸軸線。 In one embodiment, the plurality of cooling fins are disposed in a manner that is located in the combustion chamber relative to a top of the combustion chamber wall when viewed from an opposite side of the cylinder chain chamber from the cylinder axis The end portion on the cylinder axis side of the side cooling fin is located closer to the cylinder axis than the end portion on the cylinder axis side of the cooling fin opposite to the combustion chamber with respect to the top of the combustion chamber wall.
於某一實施形態中,前述冷卻空氣通道的一部分是藉由排氣通道壁所規定,該排氣通道壁規定前述排氣通道,並與前述凸輪室壁以呈銳角之方式交叉。 In one embodiment, a portion of the cooling air passage is defined by an exhaust passage wall that defines the exhaust passage and intersects the cam chamber wall at an acute angle.
於某一實施形態中,前述凸輪室壁具有1.5mm以上且2.5mm以下的厚度。 In one embodiment, the cam chamber wall has a thickness of 1.5 mm or more and 2.5 mm or less.
於某一實施形態中,前述複數個冷卻片各自的前端部,具有1.0mm以上且2.5mm以下的厚度;前述複數個冷卻片是以7.5mm以下的節距配置。 In one embodiment, the front end portions of each of the plurality of cooling fins have a thickness of 1.0 mm or more and 2.5 mm or less, and the plurality of cooling fins are arranged at a pitch of 7.5 mm or less.
於某一實施形態中,前述複數個冷卻片,各自具有1.0°以上且2.0°以下的拔模斜度。 In one embodiment, each of the plurality of cooling fins has a draft angle of 1.0° or more and 2.0° or less.
於某一實施形態中,前述缸頭本體又具有肋,該肋設置於前述冷卻空氣通道內,且連結前述燃燒室壁與前述凸輪室壁。 In one embodiment, the cylinder head body further has a rib disposed in the cooling air passage and connecting the combustion chamber wall and the cam chamber wall.
於某一實施形態中,前述肋是沿著規定前述冷卻空氣通道之冷卻空氣通道壁而形成。 In one embodiment, the rib is formed along a wall of the cooling air passage defining the cooling air passage.
於某一實施形態中,沿著正交於前述排氣通道的軸 線之面之前述排氣通道的剖面形狀的真圓度,低於前述排氣通道的出口的形狀的真圓度。 In one embodiment, along an axis orthogonal to the exhaust passage The roundness of the cross-sectional shape of the aforementioned exhaust passage on the surface of the line is lower than the roundness of the shape of the outlet of the exhaust passage.
於某一實施形態中,沿著正交於前述排氣通道的軸線之面之前述排氣通道的剖面形狀大致為橢圓,前述排氣通道的出口的形狀大致為真圓。 In one embodiment, the cross-sectional shape of the exhaust passage along a surface orthogonal to the axis of the exhaust passage is substantially elliptical, and the shape of the outlet of the exhaust passage is substantially true.
依據本發明的跨坐型車輛,具備具有上述構造之氣冷式內燃機。 A straddle type vehicle according to the present invention is provided with an air-cooled internal combustion engine having the above configuration.
於依據本發明的氣冷式內燃機中,由於缸頭本體的排氣通道是以隨著自入口側朝向出口側而遠離凸輪鏈室之方式延伸,因此,可擴大排氣通道的出口與凸輪鏈室之間的空間。因此,易於確保冷卻空氣通道的截面積足夠大。因此,可實現足夠高的冷卻性能。又,於依據本發明的內燃機中,缸頭本體的排氣通道是以軸線成直線狀之方式而形成。因此,降低排氣阻力,實現更加高效的燃燒。又,當藉由壓鑄來成形缸頭本體時,由於可藉由金屬模具來形成最終形狀的排氣通道,因此,無需藉由後加工來變更排氣通道的形狀。 In the air-cooled internal combustion engine according to the present invention, since the exhaust passage of the cylinder head body extends away from the cam chain chamber from the inlet side toward the outlet side, the outlet of the exhaust passage and the cam chain can be enlarged. The space between the rooms. Therefore, it is easy to ensure that the cross-sectional area of the cooling air passage is sufficiently large. Therefore, a sufficiently high cooling performance can be achieved. Further, in the internal combustion engine according to the present invention, the exhaust passage of the cylinder head body is formed in such a manner that the axis is linear. Therefore, the exhaust resistance is lowered to achieve more efficient combustion. Further, when the cylinder head body is formed by die casting, since the exhaust passage of the final shape can be formed by the metal mold, it is not necessary to change the shape of the exhaust passage by post-processing.
典型地,複數個冷卻片包含自用以規定排氣通道之排氣通道壁延伸之冷卻片。由於排氣通道是缸頭本體中容易變得溫度較高之處,因此,藉由使冷卻片自排氣通道壁延伸,可提高冷卻效率。 Typically, the plurality of fins comprise fins extending from the wall of the exhaust passage defining the exhaust passage. Since the exhaust passage is a place where the temperature in the cylinder head body tends to become high, the cooling efficiency can be improved by extending the cooling fin from the exhaust passage wall.
若以軸線成直線狀之方式來設置排氣通道的形狀,即使不使用模心,利用金屬模具即可容易形成排氣通道。若藉由金屬模具來形成排氣通道,則可使排氣通道的內周面的表面粗糙度小於使用模心時的表面粗糙度。更具體而言,可 使排氣通道的內周面的表面粗糙度Rz(最大高度)為30μm以下,可降低排氣阻力並提高內燃機的輸出。又,藉由使吸氣通道的內周面的表面粗糙度Rz亦為30μm以下,可降低吸氣阻力並進一步提高內燃機的輸出。 If the shape of the exhaust passage is set in a straight line, the exhaust passage can be easily formed by a metal mold without using a mold core. When the exhaust passage is formed by the metal mold, the surface roughness of the inner peripheral surface of the exhaust passage can be made smaller than the surface roughness when the core is used. More specifically, the surface roughness Rz (maximum height) of the inner circumferential surface of the exhaust passage can be made 30 μm or less, and the exhaust resistance can be lowered and the output of the internal combustion engine can be improved. Moreover, by setting the surface roughness Rz of the inner peripheral surface of the intake passage to 30 μm or less, the intake resistance can be reduced and the output of the internal combustion engine can be further improved.
若將插通有帶頭螺栓之螺栓孔設置於排氣通道與凸輪鏈室之間,則需要使冷卻空氣通道的一部分位於(配置於)比排氣通道與凸輪鏈室之間更狹窄的空間(也就是螺栓孔與排氣通道之間的空間)內。然而,如上所述,排氣通道是以隨著自入口側朝向出口側而遠離凸輪鏈室之方式延伸,藉此,即使在螺栓孔與排氣通道之間,亦可確保冷卻空氣通道的截面積足夠大。 If the bolt hole through which the cap bolt is inserted is disposed between the exhaust passage and the cam chain chamber, it is necessary to have a portion of the cooling air passage be located (disposed) in a space narrower than between the exhaust passage and the cam chain chamber ( That is, the space between the bolt hole and the exhaust passage). However, as described above, the exhaust passage extends in such a manner as to be away from the cam chain chamber from the inlet side toward the outlet side, whereby the cooling air passage can be ensured even between the bolt hole and the exhaust passage. The area is large enough.
較佳為,複數個冷卻片是以下述方式而設置:相對於燃燒室壁的頂部而位於燃燒室側之冷卻片的面積的合計,大於相對於燃燒室壁的頂部而位於與燃燒室為相反側之冷卻片的面積的合計。於內燃機的運轉中,缸頭本體中,相對於燃燒室壁的頂點部為燃燒室側的區域,比相對於燃燒室壁的頂點部與燃燒室為相反側的區域,其溫度較高。因此,藉由使位於前者的區域之冷卻片的面積的合計大於位於後者的區域之冷卻片的面積的合計,可有效地提高冷卻性。 Preferably, the plurality of cooling fins are disposed in such a manner that the total area of the cooling fins on the combustion chamber side with respect to the top of the combustion chamber wall is larger than the combustion chamber is opposite to the top of the combustion chamber wall. The total area of the cooling fins on the side. In the operation of the internal combustion engine, the apex portion of the cylinder head body is the combustion chamber side region with respect to the apex portion of the combustion chamber wall, and the temperature is higher than the region on the opposite side of the apex portion of the combustion chamber wall from the combustion chamber. Therefore, the cooling property can be effectively improved by making the total area of the cooling fins in the former region larger than the total area of the cooling fins in the latter region.
又,較佳為,複數個冷卻片是以下述方式而設置:當自相對於氣缸軸線與凸輪鏈室為相反側來觀察時,相對於燃燒室壁的頂部而位於燃燒室側之冷卻片的氣缸軸線側的端部,比相對於燃燒室壁的頂部而位於與燃燒室為相反側之冷卻片的氣缸軸線側的端部,更靠近氣缸軸線。藉由使相對於 燃燒室壁的頂點部而位於燃燒室側之冷卻片的氣缸軸線側的端部,比相對於燃燒室壁的頂點部而位於與燃燒室為相反側之冷卻片的氣缸軸線側的端部,更靠近氣缸軸線,也就是說,藉由使後者的冷卻片的端部比前者的冷卻片的端部更遠離氣缸軸線,可進一步增大冷卻空氣通道的截面積。 Further, preferably, the plurality of cooling fins are disposed in such a manner that when viewed from the opposite side with respect to the cylinder axis and the cam chain chamber, the cooling fins on the combustion chamber side with respect to the top of the combustion chamber wall The end portion on the cylinder axis side is closer to the cylinder axis than the end portion on the cylinder axis side of the cooling fin opposite to the combustion chamber with respect to the top of the combustion chamber wall. By making relative The end portion on the cylinder axis side of the cooling fin on the combustion chamber side at the apex portion of the combustion chamber wall is located at the end portion on the cylinder axis side of the cooling fin opposite to the combustion chamber with respect to the apex portion of the combustion chamber wall. Closer to the cylinder axis, that is, by making the end of the latter cooling fin farther from the cylinder axis than the end of the former cooling fin, the cross-sectional area of the cooling air passage can be further increased.
若排氣通道壁規定冷卻空氣通道的一部分,該排氣通道壁用以規定排氣通道,並與凸輪室壁以呈銳角之方式交叉,則可獲得如下所述的優點。通常,在壓鑄時藉由金屬模具來形成冷卻空氣通道的形狀的情況下,金屬模具的與冷卻空氣通道相對應之部分,具有比其他部分突出之形狀。具有此種突出之形狀之部分的前端,因熔融金屬(molten metal)的熱量而容易變得溫度較高。尤其是若前端有棱角,就可能會熔損。因此,一般而言,將前端設計成剖面為圓形,但藉由利用以與凸輪室壁成銳角之方式交叉之排氣通道壁來規定冷卻空氣通道的一部分,可增大冷卻空氣通道的截面積。此時,由於凸輪室壁與排氣通道壁的厚度均可較小,因此,可避免熔損的問題。 If the exhaust passage wall defines a portion of the cooling air passage that defines the exhaust passage and intersects the cam chamber wall at an acute angle, the advantages described below can be obtained. In general, in the case where the shape of the cooling air passage is formed by a metal mold at the time of die casting, the portion of the metal mold corresponding to the cooling air passage has a shape protruding from the other portions. The front end of the portion having such a protruding shape tends to have a high temperature due to the heat of the molten metal. In particular, if the front end has an angular shape, it may melt. Therefore, in general, the front end is designed to be circular in cross section, but the section of the cooling air passage can be increased by defining a part of the cooling air passage by using the exhaust passage wall intersecting at an acute angle to the wall of the cam chamber. area. At this time, since the thickness of the cam chamber wall and the exhaust passage wall can be small, the problem of melt loss can be avoided.
較佳為,凸輪室壁具有2.5mm以下的厚度。藉由使凸輪室壁的厚度為2.5mm以下,可更確實地防止金屬模具的棱角的熔損。但若凸輪室壁的厚度不足1.5mm,則無法充分獲得凸輪室所要求的耐壓強度(compressive strength),且對由於應變而產生的變形應力之耐性可能會不足,因此,凸輪室壁的厚度較佳為1.5mm以上。 Preferably, the cam chamber wall has a thickness of 2.5 mm or less. By making the thickness of the cam chamber wall 2.5 mm or less, it is possible to more reliably prevent the corner of the mold from being melted. However, if the thickness of the cam chamber wall is less than 1.5 mm, the compressive strength required for the cam chamber cannot be sufficiently obtained, and the resistance to deformation stress due to strain may be insufficient, and therefore, the thickness of the cam chamber wall It is preferably 1.5 mm or more.
又,於依據本發明的氣冷式內燃機中,由於缸頭本 體是藉由壓鑄而成形,因此,可縮小冷卻片的厚度與節距,並可提高冷卻性。具體而言,可使各冷卻片的前端部的厚度為1.0mm以上且2.5mm以下,並以7.5mm以下的節距來配置複數個冷卻片,藉此可提高冷卻性。 Moreover, in the air-cooled internal combustion engine according to the present invention, due to the cylinder head The body is formed by die casting, so that the thickness and pitch of the cooling fin can be reduced, and the cooling property can be improved. Specifically, the thickness of the tip end portion of each of the cooling fins can be 1.0 mm or more and 2.5 mm or less, and a plurality of cooling fins can be arranged at a pitch of 7.5 mm or less, whereby the cooling property can be improved.
較佳為,複數個冷卻片各自具有2.0°以下的拔模斜度。藉由將拔模斜度減小為2.0°以下,由於可增大冷卻片的根部之間的間隔,因此,可進一步提高冷卻性。但自易於脫模之觀點來看,複數個冷卻片各自的拔模斜度較佳為1.0°以上。 Preferably, the plurality of cooling fins each have a draft angle of 2.0 or less. By reducing the draft angle to 2.0 or less, since the interval between the root portions of the cooling fins can be increased, the cooling property can be further improved. However, from the viewpoint of easy demolding, the draft angle of each of the plurality of cooling fins is preferably 1.0 or more.
較佳為,缸頭本體進而具有肋,該肋設置於冷卻空氣通道內,且連結燃燒室壁與凸輪室壁。藉由使肋連結燃燒室壁與凸輪室壁,肋可將燃燒室壁的熱量傳達至凸輪室壁,而凸輪室可使用潤滑油來進行冷卻,因此,可提高冷卻性。又,藉由將肋配置於冷卻空氣通道內,亦可獲得由冷卻空氣所達成的冷卻效果。 Preferably, the cylinder head body further has ribs disposed in the cooling air passage and joining the combustion chamber wall and the cam chamber wall. By connecting the ribs to the combustion chamber wall and the cam chamber wall, the ribs can transfer the heat of the combustion chamber wall to the cam chamber wall, and the cam chamber can be cooled using the lubricating oil, thereby improving the cooling performance. Moreover, by arranging the ribs in the cooling air passage, the cooling effect achieved by the cooling air can also be obtained.
再者,較佳為,肋是沿著當缸頭本體以壓鑄而成形時的起模方向而形成。因此,較佳為,肋是沿著規定冷卻空氣通道之壁部(冷卻空氣通道壁)而形成。 Further, it is preferable that the rib is formed along a direction in which the mold is formed when the cylinder head body is formed by die casting. Therefore, it is preferable that the rib is formed along a wall portion (cooling air passage wall) defining a cooling air passage.
又,較佳為,沿著正交於排氣通道的軸線之面之排氣通道的剖面形狀大致為橢圓,且排氣通道的出口的形狀大致為真圓。由於排氣管的剖面形狀一般大致為真圓,因此,藉由使排氣通道的出口的形狀大致為真圓,可防止通道面積的急劇變化,並防止內燃機的性能降低。若排氣通道是以隨著自入口側朝向出口側而遠離凸輪鏈室之方式延伸,且沿著正交於軸線之面之排氣通道的剖面形狀大致為真圓,則無法 使排氣通道的出口的形狀大致為真圓。相對於此,藉由使沿著正交於軸線之面之排氣通道的剖面形狀大致為橢圓,也就是說,藉由使沿著正交於軸線之面之排氣通道的剖面形狀的真圓度,低於排氣通道的出口的形狀的真圓度,可使排氣通道的出口的形狀大致為真圓。 Further, preferably, the cross-sectional shape of the exhaust passage along the plane orthogonal to the axis of the exhaust passage is substantially elliptical, and the shape of the outlet of the exhaust passage is substantially true. Since the cross-sectional shape of the exhaust pipe is generally substantially true, by making the shape of the outlet of the exhaust passage substantially round, it is possible to prevent an abrupt change in the passage area and prevent the performance of the internal combustion engine from deteriorating. If the exhaust passage extends away from the cam chain chamber from the inlet side toward the outlet side, and the cross-sectional shape of the exhaust passage along the plane orthogonal to the axis is substantially true, The shape of the outlet of the exhaust passage is made substantially round. In contrast, the cross-sectional shape of the exhaust passage along the plane orthogonal to the axis is substantially elliptical, that is, by making the cross-sectional shape of the exhaust passage along the plane orthogonal to the axis true. The roundness, which is lower than the roundness of the shape of the outlet of the exhaust passage, makes the shape of the outlet of the exhaust passage substantially round.
依據本發明,提供一種氣冷式內燃機,該氣冷式內燃機具備缸頭本體,該缸頭本體具有擁有充分的截面積之冷卻空氣通道,且可利用壓鑄較合適地成形。 According to the present invention, there is provided an air-cooled internal combustion engine having a cylinder head body having a cooling air passage having a sufficient cross-sectional area and which can be suitably formed by die casting.
1‧‧‧機車(跨坐型車輛) 1‧‧‧Motorcycles (straddle-type vehicles)
10‧‧‧冷卻片 10‧‧‧ Cooling film
20‧‧‧凸輪室壁 20‧‧‧ cam chamber wall
30‧‧‧燃料室壁 30‧‧‧fuel chamber wall
32‧‧‧塞孔 32‧‧‧ plug hole
40‧‧‧吸氣通道 40‧‧‧ Inhalation channel
40a‧‧‧吸氣口 40a‧‧‧ suction port
40b‧‧‧開口部 40b‧‧‧ openings
50‧‧‧排氣通道 50‧‧‧Exhaust passage
50a‧‧‧排氣口(排氣通道的入口) 50a‧‧‧Exhaust port (inlet of exhaust duct)
50b‧‧‧開口部(排氣通道的出口) 50b‧‧‧ openings (exit of the exhaust passage)
50x‧‧‧排氣通道的軸線 50x‧‧‧ axis of the exhaust passage
51‧‧‧排氣通道壁 51‧‧‧Exhaust channel wall
60‧‧‧冷卻空氣通道 60‧‧‧Cooling air passage
60a‧‧‧冷卻空氣通道的入口 60a‧‧‧Environment of the cooling air passage
60b‧‧‧冷卻空氣通道的出口 60b‧‧‧Exit of the cooling air passage
70‧‧‧凸輪鏈室 70‧‧‧Cam chain room
80‧‧‧帶頭螺栓凸座 80‧‧‧Leading bolt boss
80a、80b、80c、80d‧‧‧螺栓孔 80a, 80b, 80c, 80d‧‧‧ bolt holes
90‧‧‧肋 90‧‧‧ rib
100‧‧‧缸頭本體 100‧‧‧ cylinder head body
101‧‧‧引擎(內燃機) 101‧‧‧ engine (internal combustion engine)
102‧‧‧曲軸箱 102‧‧‧ crankcase
103‧‧‧缸體 103‧‧‧Cylinder block
104‧‧‧缸頭 104‧‧‧ cylinder head
105‧‧‧氣缸頭蓋 105‧‧‧Cylinder head cover
106‧‧‧氣缸 106‧‧‧ cylinder
108‧‧‧凸輪軸 108‧‧‧Camshaft
109‧‧‧凸輪室 109‧‧‧Cam room
110‧‧‧燃燒室 110‧‧‧ combustion chamber
113‧‧‧凸輪鏈 113‧‧‧Cam chain
121‧‧‧冷卻風扇 121‧‧‧Cooling fan
130‧‧‧圍板 130‧‧‧
141‧‧‧吸氣管 141‧‧‧ suction pipe
142‧‧‧排氣管 142‧‧‧Exhaust pipe
161‧‧‧吸氣閥 161‧‧‧ Inhalation valve
162‧‧‧排氣閥 162‧‧‧Exhaust valve
CA‧‧‧冷卻空氣 CA‧‧‧Cooling air
D1‧‧‧氣缸軸線方向 D1‧‧‧Cylinder axis direction
L1‧‧‧氣缸軸線 L1‧‧‧Cylinder axis
第1圖是示意地繪示本發明的實施形態中的機車(跨坐型車輛)1的右側視圖。 Fig. 1 is a right side view schematically showing a locomotive (straddle type vehicle) 1 in an embodiment of the present invention.
第2圖是沿著第1圖中的2A-2A’線的剖面圖。 Fig. 2 is a cross-sectional view taken along line 2A-2A' in Fig. 1.
第3圖是放大地繪示第2圖中所繪示的引擎(內燃機)101附近的圖。 Fig. 3 is an enlarged view of the vicinity of an engine (internal combustion engine) 101 shown in Fig. 2.
第4圖是引擎101的一部分的右側視圖。 FIG. 4 is a right side view of a portion of the engine 101.
第5圖是引擎101的左側面剖面圖。 Fig. 5 is a cross-sectional view of the left side of the engine 101.
第6圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的俯視圖。 Fig. 6 is a plan view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第7圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的仰視圖。 Fig. 7 is a bottom view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第8圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的前視圖。 Fig. 8 is a front view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第9圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的後視圖。 Fig. 9 is a rear elevational view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第10圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的左側視圖。 Fig. 10 is a left side view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第11圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的右側視圖。 Fig. 11 is a right side view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention.
第12圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的圖,是沿著第11圖中的12A-12A’線的剖面圖。 Fig. 12 is a view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention, and is a cross-sectional view taken along line 12A-12A' in Fig. 11.
第13圖是示意地繪示本發明的實施形態中的引擎101所具備的缸頭本體100的圖,是沿著第7圖中的13A-13A’線的剖面圖。 Fig. 13 is a view schematically showing the cylinder head main body 100 of the engine 101 according to the embodiment of the present invention, and is a cross-sectional view taken along line 13A-13A' in Fig. 7.
第14圖是示意地繪示缸頭本體100所具有的複數個冷卻片10的圖。 Fig. 14 is a view schematically showing a plurality of cooling fins 10 included in the cylinder head body 100.
以下,一邊參照圖式一邊說明本發明的實施形態。再者,本發明並非限定於以下的實施形態。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Furthermore, the present invention is not limited to the following embodiments.
於第1圖中,繪示出本實施形態中的跨坐型車輛1。第1圖所示的跨坐型車輛1為速克達型(scooter type)的機車。再者,依據本發明的跨坐型車輛,並非限定於速克達型的機車1。依據本發明的跨坐型車輛,亦可為所謂的輕型機踏型(moped type)、越野型(off-road type)型及公路型(on-road type)等其他形式的機車。又,依據本發明的跨坐型車輛是指由騎乘者跨騎乘車的任意車輛,並非限定於二輪車。依據本發明 的跨坐型車輛,可為藉由使車體傾斜來改變行進方向之形式的三輪車等,亦可為全地形車輛(All Terrain Vehicle,ATV)等其他跨坐型車輛。 In the first drawing, the straddle type vehicle 1 in the present embodiment is shown. The straddle type vehicle 1 shown in Fig. 1 is a scooter type locomotive. Furthermore, the straddle type vehicle according to the present invention is not limited to the locomotive 1 of the Scooton type. The straddle type vehicle according to the present invention may be other types of locomotives such as a so-called moped type, an off-road type, and an on-road type. Further, the straddle type vehicle according to the present invention refers to any vehicle that is ridden by a rider, and is not limited to a two-wheeled vehicle. According to the invention The straddle type vehicle may be a tricycle or the like in the form of changing the traveling direction by tilting the vehicle body, or may be another straddle type vehicle such as an All Terrain Vehicle (ATV).
於以下的說明中,前、後、左、右分別是指由機車1的騎乘者來觀察時的前、後、左、右。圖中的參照符號F、Re、L、R分別表示前、後、左、右。 In the following description, the front, the rear, the left, and the right respectively refer to the front, rear, left, and right when viewed by the rider of the locomotive 1. Reference symbols F, Re, L, and R in the figure denote front, back, left, and right, respectively.
如第1圖所示,機車1具備:車輛本體2、前輪3、後輪4、及驅動後輪4之引擎單元5。車輛本體2具備供騎乘者操作之手柄6、及騎乘者就座之座椅7。引擎單元5是所謂的單元擺動(unit swing)式引擎單元,以樞軸8為中心且以可搖動的方式被車體框架(第1圖中未示出)支撐。亦即,引擎單元5以可搖動的方式被車體框架支撐。 As shown in FIG. 1, the locomotive 1 includes a vehicle body 2, a front wheel 3, a rear wheel 4, and an engine unit 5 that drives the rear wheel 4. The vehicle body 2 is provided with a handle 6 for the rider to operate, and a seat 7 for the rider to sit. The engine unit 5 is a so-called unit swing type engine unit that is supported by a vehicle body frame (not shown in Fig. 1) centered on the pivot shaft 8 in a swingable manner. That is, the engine unit 5 is supported by the vehicle body frame in a swingable manner.
繼而,一邊參照第2圖~第5圖,一邊更具體地說明機車1的引擎單元5的構成。第2圖是沿著第1圖中的2A-2A’線的剖面圖。第3圖是放大地繪示第2圖中所繪示的引擎101附近的圖。第4圖是引擎101的一部分的右側視圖。第5圖是引擎101的左側面剖面圖。 Next, the configuration of the engine unit 5 of the locomotive 1 will be described more specifically with reference to FIGS. 2 to 5 . Fig. 2 is a cross-sectional view taken along line 2A-2A' in Fig. 1. Fig. 3 is an enlarged view of the vicinity of the engine 101 shown in Fig. 2. FIG. 4 is a right side view of a portion of the engine 101. Fig. 5 is a cross-sectional view of the left side of the engine 101.
如第2圖所示,引擎單元5具備引擎(內燃機)101、與V型皮帶式無段變速器(以下稱為「continuously variable transmission,CVT」)150。再者,於第2圖所示的一例中,引擎101與CVT150一體地構成引擎單元5,然而,引擎101與變速器當然亦可分開。 As shown in FIG. 2, the engine unit 5 includes an engine (internal combustion engine) 101 and a V-belt type stepless transmission (hereinafter referred to as "continuously variable transmission (CVT)) 150. Further, in the example shown in FIG. 2, the engine 101 and the CVT 150 integrally constitute the engine unit 5. However, the engine 101 and the transmission may of course be separated.
引擎101為具備單一的汽缸之單缸引擎。引擎101為依次重複吸氣步驟、壓縮步驟、燃燒步驟及排氣步驟之四 衝程引擎。引擎101具備:曲軸箱102;缸體(cylinder block)103,其自曲軸箱102向前方(再者,此處所述的「前方」並非限定於嚴格意義上的前方,亦即並非限定於平行於水平線之方向,亦包含自水平線傾斜之方向)延伸,並與曲軸箱102結合;缸頭104,其連接於缸體103的前部;及,氣缸頭蓋105,其連接於缸頭104的前部。於缸體103的內部,形成有氣缸106。 The engine 101 is a single cylinder engine having a single cylinder. The engine 101 repeats the inhalation step, the compression step, the combustion step, and the exhaust step in sequence. Stroke engine. The engine 101 includes a crankcase 102 and a cylinder block 103 which is forward from the crankcase 102. (Further, the "front" described herein is not limited to the front in a strict sense, that is, it is not limited to parallel. In the direction of the horizontal line, also extending from the direction of the horizontal line inclination, and combined with the crankcase 102; the cylinder head 104 is connected to the front portion of the cylinder block 103; and the cylinder head cover 105 is connected to the front of the cylinder head 104. unit. Inside the cylinder 103, a cylinder 106 is formed.
再者,氣缸106可藉由***至缸體103的本體(亦即,缸體103中的除了氣缸106以外的部分)內之氣缸襯套(cylinder liner)等所形成,亦可與缸體103的本體一體化。換言之,氣缸106可形成為能夠與缸體103的本體分離,亦可形成為不能與缸體103的本體分離。活塞107滑動自如地容置於氣缸106內。活塞107被配置成在上死點TDC(top dead center)與下死點BDC(bottom dead center)之間往復移動自如地動作。 Further, the cylinder 106 may be formed by a cylinder liner or the like inserted into the body of the cylinder 103 (that is, a portion other than the cylinder 106 in the cylinder 103), or may be connected to the cylinder 103. The integration of the ontology. In other words, the cylinder 106 may be formed to be separable from the body of the cylinder 103 or may be formed so as not to be separated from the body of the cylinder 103. The piston 107 is slidably housed in the cylinder 106. The piston 107 is disposed to reciprocately move between a top dead center TDC (top dead center) and a bottom dead center BDC (bottom dead center).
缸頭104是以覆蓋氣缸106之方式,重疊於缸體103上。缸頭104具有:鋁合金製造的缸頭本體100、包含凸輪軸108之閥動機構(valve gear)、及吸氣閥161和排氣閥162等。閥動機構容置於凸輪室109內。缸頭本體100的用以規定凸輪室109之部分20,如下所述,稱為凸輪室壁。 The cylinder head 104 is superposed on the cylinder block 103 so as to cover the cylinder 106. The cylinder head 104 has a cylinder head body 100 made of an aluminum alloy, a valve gear including a cam shaft 108, an intake valve 161, an exhaust valve 162, and the like. The valve mechanism is housed in the cam chamber 109. The portion 20 of the cylinder head body 100 for defining the cam chamber 109 is referred to as a cam chamber wall as described below.
燃燒室110是由缸頭本體100、活塞107的頂面、及氣缸106的內周面所規定。缸頭100本體的規定燃燒室110之部分30,如下所述,稱為燃燒室壁。 The combustion chamber 110 is defined by the cylinder head body 100, the top surface of the piston 107, and the inner circumferential surface of the cylinder 106. The portion 30 of the body of the cylinder head 100 that defines the combustion chamber 110 is referred to as the combustion chamber wall as described below.
活塞107經由連桿111連結於曲柄軸112。曲柄軸 112向左方和右方延伸,且被曲軸箱102所支撐。藉由連接於曲柄軸112上之凸輪鏈113來驅動凸輪軸108。凸輪鏈113容置於凸輪鏈室70內。 The piston 107 is coupled to the crankshaft 112 via a link 111. Crankshaft 112 extends to the left and to the right and is supported by the crankcase 102. The camshaft 108 is driven by a cam chain 113 coupled to the crankshaft 112. The cam chain 113 is housed in the cam chain chamber 70.
再者,於本實施形態中,曲軸箱102、缸體103、缸頭104及氣缸頭蓋105為分體,但該等並非必須為分體(分離的構件),亦可適當一體化。例如,曲軸箱102與缸體103可一體形成,缸體103與缸頭104亦可一體形成。又,缸頭104與氣缸頭蓋105亦可一體形成。 Further, in the present embodiment, the crankcase 102, the cylinder block 103, the cylinder head 104, and the cylinder head cover 105 are separate bodies, but these are not necessarily separate bodies (separate members), and may be appropriately integrated. For example, the crankcase 102 and the cylinder 103 may be integrally formed, and the cylinder 103 and the cylinder head 104 may be integrally formed. Further, the cylinder head 104 and the cylinder head cover 105 may be integrally formed.
如第2圖所示,CVT150具備:驅動側的滑輪亦即第1滑輪151、從動側的滑輪亦即第2滑輪152、及捲繞於第1滑輪151和第2滑輪152上之V型皮帶153。曲柄軸112的左端部自曲軸箱102向左方突出。第1滑輪151安裝於曲柄軸112的左端部上。第2滑輪152安裝於主軸154上。主軸154經由未圖示之齒輪機構,連結於後輪軸155上。於曲軸箱102的左方,設置有變速機殼體156。CVT150容置於變速機殼體156內。 As shown in FIG. 2, the CVT 150 includes a first pulley 151 which is a pulley on the driving side, a second pulley 152 which is a pulley on the driven side, and a V-shaped wound around the first pulley 151 and the second pulley 152. Belt 153. The left end portion of the crankshaft 112 protrudes leftward from the crankcase 102. The first pulley 151 is attached to the left end portion of the crankshaft 112. The second pulley 152 is attached to the main shaft 154. The main shaft 154 is coupled to the rear wheel shaft 155 via a gear mechanism (not shown). On the left side of the crankcase 102, a transmission housing 156 is provided. The CVT 150 is housed within the shifter housing 156.
於曲柄軸112的右側部分上,設置有發電機120。於曲柄軸112的右端部上,固定有冷卻風扇121。冷卻風扇121與曲柄軸112一起旋轉。冷卻風扇121是以藉由旋轉將空氣吸引至左方之方式而形成。於曲軸箱102、缸體103及缸頭104上,設置有圍板(shroud)130。發電機120和冷卻風扇121容置於圍板130內。 On the right side portion of the crankshaft 112, a generator 120 is disposed. A cooling fan 121 is fixed to the right end portion of the crankshaft 112. The cooling fan 121 rotates together with the crankshaft 112. The cooling fan 121 is formed by sucking air to the left by rotation. A shroud 130 is disposed on the crankcase 102, the cylinder 103, and the cylinder head 104. The generator 120 and the cooling fan 121 are housed in the enclosure 130.
如第4圖所示,引擎101是所謂的橫置式引擎,亦即缸體103和缸頭104向水平方向或自水平方向稍微前高後 低地傾斜之方向延伸。圖中的參照符號L1表示通過氣缸106的中心之線(氣缸軸線)。氣缸軸線L1向水平方向或自水平方向稍微傾斜之方向延伸。但氣缸軸線L1的方向並無特別限定。例如,氣缸軸線L1相對於水平面之傾斜角度可為0°~15°,亦可為該範圍以上。再者,圖中的參照符號L2表示曲柄軸112的中心線。 As shown in Fig. 4, the engine 101 is a so-called transverse engine, that is, the cylinder 103 and the cylinder head 104 are slightly higher in the horizontal direction or from the horizontal direction. The low ground extends in the direction of inclination. Reference symbol L1 in the figure denotes a line (cylinder axis) passing through the center of the cylinder 106. The cylinder axis L1 extends in a horizontal direction or a direction slightly inclined from the horizontal direction. However, the direction of the cylinder axis L1 is not particularly limited. For example, the inclination angle of the cylinder axis L1 with respect to the horizontal plane may be 0 to 15 degrees, or may be above the range. Furthermore, reference symbol L2 in the figure denotes a center line of the crankshaft 112.
於缸頭104的上部,連接有吸氣管141。又,於缸頭104的下部,連接有排氣管142。於缸頭104的內部,形成有吸氣通道40和排氣通道50。吸氣管141與吸氣通道40連接,排氣管142與排氣通道50連接。於吸氣通道40和排氣通道50,分別設置有吸氣閥161和排氣閥162。 An intake pipe 141 is connected to an upper portion of the cylinder head 104. Further, an exhaust pipe 142 is connected to a lower portion of the cylinder head 104. Inside the cylinder head 104, an intake passage 40 and an exhaust passage 50 are formed. The intake pipe 141 is connected to the intake passage 40, and the exhaust pipe 142 is connected to the exhaust passage 50. An intake valve 161 and an exhaust valve 162 are provided in the intake passage 40 and the exhaust passage 50, respectively.
本實施形態的引擎101為利用空氣冷卻之氣冷式引擎。如第2圖~第4圖所示,於缸體103中,形成有複數個冷卻片114。冷卻片114在與氣缸軸線L1大致正交(垂直)之方向上延伸。再者,如後所述,於缸頭本體100上亦形成有複數個冷卻片10(請參照第8圖~第10圖)。 The engine 101 of the present embodiment is an air-cooled engine that is cooled by air. As shown in FIGS. 2 to 4, a plurality of cooling fins 114 are formed in the cylinder 103. The cooling fins 114 extend in a direction substantially orthogonal (vertical) to the cylinder axis L1. Further, as will be described later, a plurality of cooling fins 10 are also formed on the cylinder head main body 100 (refer to Figs. 8 to 10).
圍板130具有內側構件131與外側構件132,是藉由內側構件131與外側構件132組合而形成。如第4圖所示,內側構件131與外側構件132是藉由螺栓133來固定。內側構件131和外側構件132,例如是由合成樹脂形成。 The shingle 130 has an inner member 131 and an outer member 132 formed by combining the inner member 131 and the outer member 132. As shown in FIG. 4, the inner member 131 and the outer member 132 are fixed by bolts 133. The inner member 131 and the outer member 132 are formed, for example, of a synthetic resin.
於內側構件131上形成有孔131a,該孔131a中***有火星塞(spark plug)等點火裝置115。於外側構件132上,形成有吸入口132a。當將圍板130安裝於引擎單元5上時,吸入口132a配置於與冷卻風扇121相對向之位置上(請參照第 3圖)。第4圖中的參照符號F表示冷卻風扇121的外周,參照符號B表示冷卻風扇121的旋轉方向。 A hole 131a is formed in the inner member 131, and an ignition device 115 such as a spark plug is inserted into the hole 131a. A suction port 132a is formed in the outer member 132. When the enclosure 130 is attached to the engine unit 5, the suction port 132a is disposed at a position opposed to the cooling fan 121 (please refer to 3)). Reference symbol F in Fig. 4 denotes the outer circumference of the cooling fan 121, and reference symbol B denotes the rotation direction of the cooling fan 121.
圍板130,安裝於曲軸箱102、缸體103及缸頭104上,並以沿著缸體103和缸頭104之方式向前方延伸。圍板130覆蓋曲軸箱102、缸體103及缸頭104的右側部分。又,圍板130的一部分,亦覆蓋缸體103和缸頭104的上側部分和下側部分的一部分。 The shroud 130 is attached to the crankcase 102, the cylinder 103, and the cylinder head 104, and extends forward along the cylinder 103 and the cylinder head 104. The shroud 130 covers the crankcase 102, the cylinder 103, and the right side portion of the cylinder head 104. Further, a portion of the shroud 130 also covers a portion of the upper and lower portions of the cylinder 103 and the cylinder head 104.
若冷卻風扇121伴隨著曲柄軸112的旋轉而旋轉,圍板130的外部的空氣將通過吸入口132a而被導入至圍板130內。導入至圍板130內之空氣被吹到缸體103和缸頭104上。缸體103和缸頭104利用此空氣而被冷卻。 When the cooling fan 121 rotates in accordance with the rotation of the crankshaft 112, the air outside the shingle 130 is introduced into the enclosure 130 through the suction port 132a. The air introduced into the enclosure 130 is blown onto the cylinder 103 and the cylinder head 104. The cylinder 103 and the cylinder head 104 are cooled by this air.
繼而,一邊參照第6圖~第13圖,一邊具體地說明本實施形態中的引擎101所具備的缸頭本體100的構造。第6圖和第7圖是示意地繪示缸頭本體100的俯視圖和仰視圖。第8圖和第9圖是示意地繪示缸頭本體100的前視圖和後視圖。第10圖和第11圖是示意地繪示缸頭本體100的左側視圖和右側視圖。又,第12圖是沿著第11圖中的12A-12A’線的剖面圖,第13圖是沿著第7圖中的13A-13A’線的剖面圖。於部分圖式中,氣缸軸線方向是以箭頭D1表示。再者,當然氣缸軸線方向是指平行於氣缸軸線L1之方向。又,以下,將得以連接至吸氣管141之一側作為缸頭本體100的正面側並進行說明。 Next, the structure of the cylinder head main body 100 provided in the engine 101 in the present embodiment will be specifically described with reference to FIGS. 6 to 13 . 6 and 7 are a plan view and a bottom view schematically showing the cylinder head body 100. 8 and 9 are a front view and a rear view schematically showing the cylinder head body 100. 10 and 11 are a left side view and a right side view schematically showing the cylinder head body 100. Further, Fig. 12 is a cross-sectional view taken along line 12A-12A' in Fig. 11, and Fig. 13 is a cross-sectional view taken along line 13A-13A' in Fig. 7. In the partial drawings, the cylinder axis direction is indicated by an arrow D1. Further, of course, the cylinder axis direction means a direction parallel to the cylinder axis L1. In the following description, one side of the intake pipe 141 is connected to the front side of the cylinder head main body 100 and will be described.
如第6圖~第13圖所示,缸頭本體100,具有:複數個冷卻片10、凸輪室壁20及燃燒室壁30。缸頭本體100, 進而具有:吸氣通道40、排氣通道50及冷卻空氣通道60。 As shown in FIGS. 6 to 13, the cylinder head body 100 has a plurality of cooling fins 10, a cam chamber wall 20, and a combustion chamber wall 30. Cylinder head body 100, Further, it has an intake passage 40, an exhaust passage 50, and a cooling air passage 60.
如第8圖、第9圖及第10圖所示,複數個冷卻片10,設置於缸頭本體100的外側面(更具體而言為左側面)上,並以向缸頭本體100的外側突出之方式(也就是以在大致正交於氣缸軸線方向D1之方向上延伸之方式)而形成。又,複數個冷卻片10沿著氣缸軸線方向D1,以特定的節距配置。再者,冷卻片10的個數並非限定於此處所例示之個數。 As shown in FIGS. 8 , 9 , and 10 , a plurality of cooling fins 10 are provided on the outer side surface (more specifically, the left side surface) of the cylinder head body 100 and are directed to the outside of the cylinder head body 100. The manner of protrusion (that is, the manner of extending in a direction substantially orthogonal to the cylinder axis direction D1) is formed. Further, a plurality of cooling fins 10 are arranged at a specific pitch along the cylinder axis direction D1. Furthermore, the number of the cooling fins 10 is not limited to the number exemplified herein.
第6圖、第10圖及第13圖中所示之凸輪室壁20,規定凸輪室109。凸輪室109容置包含凸輪軸108之閥動機構。安裝於缸頭本體100的上部之氣缸頭蓋105與凸輪室壁20之間的空間,構成凸輪室109。 The cam chamber wall 20 shown in Figs. 6, 10, and 13 defines a cam chamber 109. The cam chamber 109 houses a valve mechanism including a cam shaft 108. A space between the cylinder head cover 105 attached to the upper portion of the cylinder head body 100 and the cam chamber wall 20 constitutes a cam chamber 109.
第7圖、第10圖及第13圖所示之燃燒室壁30,規定燃燒室110。燃燒室110,是由缸頭本體100的燃燒室壁30、活塞107的頂面及氣缸106的內周面所形成之空間。如第7圖所示,於燃燒室壁30上,除了後述的吸氣口40a和排氣口50a以外,形成有塞孔(plug hole)32。於塞孔32中,安裝有點火裝置115的火星塞。 The combustion chamber wall 30 shown in Figs. 7, 10, and 13 defines a combustion chamber 110. The combustion chamber 110 is a space formed by the combustion chamber wall 30 of the cylinder head body 100, the top surface of the piston 107, and the inner circumferential surface of the cylinder 106. As shown in Fig. 7, a plug hole 32 is formed in the combustion chamber wall 30 in addition to the intake port 40a and the exhaust port 50a which will be described later. In the plug hole 32, a spark plug of the ignition device 115 is mounted.
吸氣通道40是用以對燃燒室110進行吸氣之通道。吸氣通道40的燃燒室壁30側的開口部40a為吸氣口。藉由閥動機構使吸氣閥161上下移動,藉此來開閉吸氣口40a。於吸氣通道40的與燃燒室壁30為相反側之開口部40b(位於缸頭本體100的正面)上,連接有吸氣管141。 The intake passage 40 is a passage for sucking the combustion chamber 110. The opening 40a on the combustion chamber wall 30 side of the intake passage 40 is an intake port. The intake valve 161 is moved up and down by the valve mechanism to open and close the intake port 40a. An intake pipe 141 is connected to an opening 40b (on the front surface of the cylinder head body 100) on the opposite side of the combustion chamber wall 30 of the intake passage 40.
排氣通道50是用以自燃燒室110進行排氣之通道。排氣通道50的燃燒室壁30側的開口部50a為排氣口。藉由 閥動機構使排氣閥162上下移動,藉此來開閉排氣口50a。於排氣通道50的與燃燒室壁30為相反側之開口部50b上,連接有排氣管142。 The exhaust passage 50 is a passage for exhausting from the combustion chamber 110. The opening portion 50a of the exhaust passage 50 on the combustion chamber wall 30 side is an exhaust port. By The valve mechanism moves the exhaust valve 162 up and down, thereby opening and closing the exhaust port 50a. An exhaust pipe 142 is connected to the opening 50b of the exhaust passage 50 opposite to the combustion chamber wall 30.
典型地,複數個冷卻片10包含自用以規定排氣通道50之排氣通道壁延伸之冷卻片10(於第10圖中,相對地位於右側)。於本實施形態中,複數個冷卻片10,進而包含自用以規定吸氣通道40之吸氣通道壁延伸之冷卻片10(於第10圖中,相對地位於左側)。 Typically, a plurality of cooling fins 10 include cooling fins 10 extending from the exhaust passage walls defining the exhaust passage 50 (in Fig. 10, relatively on the right side). In the present embodiment, the plurality of cooling fins 10 further include cooling fins 10 extending from the wall of the intake passage defining the intake passage 40 (in the tenth figure, relatively on the left side).
第10圖和第13圖所示之冷卻空氣通道60是用以使凸輪室壁20和燃燒室壁30之間通過冷卻空氣之通道。如第7圖所示,冷卻空氣通道60的入口60a,位於缸頭本體100的左側面,冷卻空氣通道60的出口60b,位於缸頭本體100的右側面。藉由冷卻風扇121而被導入至圍板130內之冷卻空氣CA,自入口60a導入至冷卻空氣通道60內,於通過冷卻空氣通道60之過程中,將缸頭本體100冷卻後,自出口60b排出至缸頭本體100的外部。 The cooling air passage 60 shown in Figs. 10 and 13 is a passage for passing the cooling air between the cam chamber wall 20 and the combustion chamber wall 30. As shown in Fig. 7, the inlet 60a of the cooling air passage 60 is located on the left side of the cylinder head body 100, and the outlet 60b of the cooling air passage 60 is located on the right side of the cylinder head body 100. The cooling air CA introduced into the enclosure 130 by the cooling fan 121 is introduced into the cooling air passage 60 from the inlet 60a. After passing through the cooling air passage 60, the cylinder head 100 is cooled from the outlet 60b. It is discharged to the outside of the cylinder head body 100.
缸頭本體100,是藉由壓鑄而由鋁合金一體成形。作為鋁合金,適合使用例如ADC10和ADC12。 The cylinder head body 100 is integrally formed of an aluminum alloy by die casting. As the aluminum alloy, for example, ADC10 and ADC12 are suitably used.
如第6圖、第7圖及第12圖所示,缸頭本體100,進而具有容置凸輪鏈113之凸輪鏈室70。凸輪鏈113是用以驅動閥動機構的凸輪軸108之構件。 As shown in FIGS. 6 , 7 , and 12 , the cylinder head body 100 further has a cam chain chamber 70 that houses the cam chain 113 . The cam chain 113 is a member for driving the cam shaft 108 of the valve mechanism.
當自氣缸軸線方向D1(第6圖、第7圖及第12圖中的垂直於紙面之方向)來觀察時,排氣通道50是以隨著從入口(排氣口50a)側朝向出口(開口部50b)側而遠離凸輪 鏈室70之方式延伸。亦即,排氣通道50的軸線50x,相對於缸頭本體100的前後方向而傾斜。又,當自氣缸軸線方向D1來觀察時,排氣通道50是以其軸線50x成直線狀之方式而形成。 When viewed from the cylinder axis direction D1 (the direction perpendicular to the paper surface in FIGS. 6 , 7 and 12), the exhaust passage 50 is directed toward the outlet from the inlet (exhaust port 50a) side ( Opening portion 50b) side away from the cam The chain chamber 70 extends in a manner. That is, the axis 50x of the exhaust passage 50 is inclined with respect to the front-rear direction of the cylinder head body 100. Further, when viewed from the cylinder axis direction D1, the exhaust passage 50 is formed in such a manner that its axis 50x is linear.
又,如第6圖、第7圖及第12圖所示,缸頭本體100,具有分別插通有帶頭螺栓之複數個螺栓孔80a~80d。藉由插通於該等螺栓孔80a~80d之帶頭螺栓(典型地為無頭螺栓(螺樁)),缸頭本體100與缸體103結合。複數個(此處為4個)螺栓孔80a~80d的其中一個螺栓孔(於第6圖和第12圖中位於右上方、於第7圖中位於右下方之螺栓孔)80a,被設置於排氣通道50與凸輪鏈室70之間。冷卻空氣通道60的一部分位於此螺栓孔80a與排氣通道50之間。具有螺栓孔80a~80d之凸座80,有時亦稱為帶頭螺栓用凸座或無頭螺栓用凸座。 Further, as shown in Fig. 6, Fig. 7, and Fig. 12, the cylinder head main body 100 has a plurality of bolt holes 80a to 80d through which the head bolts are respectively inserted. The cylinder head body 100 is coupled to the cylinder block 103 by a head bolt (typically a head bolt (stud)) inserted through the bolt holes 80a to 80d. One of a plurality of (here, four) bolt holes 80a to 80d (a bolt hole located at the upper right in FIGS. 6 and 12 and located at the lower right in FIG. 7) is disposed at The exhaust passage 50 is between the cam chain chamber 70. A portion of the cooling air passage 60 is located between the bolt hole 80a and the exhaust passage 50. The boss 80 having the bolt holes 80a to 80d is sometimes referred to as a boss for the head bolt or a boss for the headless bolt.
如上所述,本發明的實施形態中的引擎(內燃機)101的缸頭本體100是藉由壓鑄一體成形。也就是說,於缸頭本體100中,不同於專利文獻1的缸頭,並未澆鑄分體(分離)的構件亦即襯套。因此,不會由於襯套的位置偏移而導致產生吸氣通道40和排氣通道50的位置偏移,且可防止由於吸氣通道40和排氣通道50的位置偏移所導致的引擎101的性能降低。 As described above, the cylinder head main body 100 of the engine (internal combustion engine) 101 in the embodiment of the present invention is integrally molded by die casting. That is, in the cylinder head main body 100, unlike the cylinder head of Patent Document 1, the separate (separate) member, that is, the bushing, is not cast. Therefore, the positional deviation of the intake passage 40 and the exhaust passage 50 is not caused due to the positional deviation of the bushing, and the engine 101 due to the positional deviation of the intake passage 40 and the exhaust passage 50 can be prevented. The performance is reduced.
又,由於排氣通道50是以隨著自入口側朝向出口側而遠離凸輪鏈室70之方式延伸,因此,可擴大排氣通道50的出口與凸輪鏈室70之間的空間。因此,易於確保冷卻空氣 通道60的截面積足夠大。因此,可實現足夠高的冷卻性能。 Further, since the exhaust passage 50 extends away from the cam chain chamber 70 from the inlet side toward the outlet side, the space between the outlet of the exhaust passage 50 and the cam chain chamber 70 can be enlarged. Therefore, it is easy to ensure cooling air The cross-sectional area of the passage 60 is sufficiently large. Therefore, a sufficiently high cooling performance can be achieved.
進而,排氣通道50是以其軸線50x成直線狀之方式而形成。因此,可降低排氣阻力,實現更加高效的燃燒。又,當藉由壓鑄來成形缸頭本體100時,由於可藉由金屬模具來形成最終形狀的排氣通道50,因此,無需藉由後加工來變更排氣通道50的形狀。 Further, the exhaust passage 50 is formed such that its axis 50x is linear. Therefore, the exhaust resistance can be reduced to achieve more efficient combustion. Further, when the cylinder head body 100 is formed by die casting, since the final shape of the exhaust passage 50 can be formed by the metal mold, it is not necessary to change the shape of the exhaust passage 50 by post-processing.
再者,自確保冷卻空氣通道60的截面積足夠大之觀點來看,較佳為,排氣通道50的軸線50x相對於前後方向以某種程度以上的較大的角度而傾斜。具體而言,較佳為,當自氣缸軸線方向D1來觀察時,排氣通道50的軸線50x,相對於連結4個螺栓孔80a~80d中的位於凸輪鏈室70側之2個螺栓孔80a和80b的中心之直線L3,以呈20°以上的角度之方式而傾斜。但若傾斜角度過大,由於排氣阻力可能變得過大,因此,傾斜角度較佳為30°以下。 Further, from the viewpoint of ensuring that the cross-sectional area of the cooling air passage 60 is sufficiently large, it is preferable that the axis 50x of the exhaust passage 50 is inclined with respect to the front-rear direction by a large angle of a certain degree or more. Specifically, it is preferable that the axis 50x of the exhaust passage 50 is opposite to the two bolt holes 80a on the side of the cam chain chamber 70 among the four bolt holes 80a to 80d when viewed from the cylinder axis direction D1. The straight line L3 of the center of 80b is inclined at an angle of 20 or more. However, if the inclination angle is too large, the exhaust resistance may become excessively large, and therefore, the inclination angle is preferably 30 or less.
如本實施形態,若複數個螺栓孔80a~80d中的某個螺栓孔80a設置於排氣通道50與凸輪鏈室70之間,則需要使冷卻空氣通道60的一部分位於(配置於)比排氣通道50與凸輪鏈室70之間更狹窄的空間(也就是螺栓孔80a與排氣通道50之間的空間)內。然而,如上所述,排氣通道50是以隨著自入口側朝向出口側而遠離凸輪鏈室70之方式延伸,藉此,即便於螺栓孔80a與排氣通道50之間,亦可確保冷卻空氣通道60的截面積足夠大。 In the present embodiment, if one of the plurality of bolt holes 80a to 80d is provided between the exhaust passage 50 and the cam chain chamber 70, it is necessary to position (arrange) a part of the cooling air passage 60. The narrower space between the air passage 50 and the cam chain chamber 70 (that is, the space between the bolt hole 80a and the exhaust passage 50). However, as described above, the exhaust passage 50 extends away from the cam chain chamber 70 from the inlet side toward the outlet side, whereby cooling can be ensured even between the bolt hole 80a and the exhaust passage 50. The cross-sectional area of the air passage 60 is sufficiently large.
又,若以軸線50x成直線狀之方式,來設計排氣通道50的形狀,即便不使用模心,藉由金屬模具即可容易形成 排氣通道50。若藉由金屬模具來形成排氣通道50,則可使排氣通道50的內周面的表面粗糙度小於使用模心時的表面粗糙度。更具體而言,可使排氣通道50的內周面的表面粗糙度Rz(最大高度)為30μm以下,可降低排氣阻力並提高引擎101的輸出。再者,藉由使吸氣通道40的內周面的表面粗糙度Rz亦為30μm以下,可降低吸氣阻力並進一步提高引擎101的輸出。 Further, if the shape of the exhaust passage 50 is designed such that the axis 50x is linear, the exhaust passage 50 can be easily formed by the metal mold without using the mold core. When the exhaust passage 50 is formed by a metal mold, the surface roughness of the inner circumferential surface of the exhaust passage 50 can be made smaller than the surface roughness when the core is used. More specifically, the surface roughness Rz (maximum height) of the inner circumferential surface of the exhaust passage 50 can be made 30 μm or less, which can reduce the exhaust resistance and increase the output of the engine 101. In addition, by setting the surface roughness Rz of the inner peripheral surface of the intake passage 40 to 30 μm or less, the intake resistance can be reduced and the output of the engine 101 can be further increased.
較佳為,複數個冷卻片10包含自用以規定排氣通道50之排氣通道壁延伸之冷卻片10。由於排氣通道50是在缸頭本體100中亦容易變得溫度較高之處,因此,藉由使冷卻片10自排氣通道壁延伸,可提高冷卻效率。自充分確保較高的冷卻效率之觀點來看,更具體而言,自排氣通道壁延伸之冷卻片10,是自排氣通道壁中的至少比與螺栓孔(最接近於自排氣通道壁延伸之冷卻片10之螺栓孔)80c相對應之凸座(無頭螺栓用凸座)80更接近氣缸軸線L1側之部分延伸(參照第10圖)。 Preferably, the plurality of cooling fins 10 comprise cooling fins 10 extending from the wall of the exhaust passage defining the exhaust passage 50. Since the exhaust passage 50 is also likely to become higher in the cylinder head body 100, the cooling efficiency can be improved by extending the cooling fins 10 from the exhaust passage walls. From the standpoint of sufficiently ensuring a higher cooling efficiency, more specifically, the cooling fins 10 extending from the wall of the exhaust passage are at least as compared with the bolt holes in the wall of the exhaust passage (closest to the self-venting passage) The bolt hole 80c of the wall extending cooling block 10c extends in a portion closer to the cylinder axis L1 side than the boss (the boss for the head bolt) 80 (refer to Fig. 10).
此處,將複數個冷卻片10中的相對於燃燒室壁30的頂部而位於燃燒室110側之冷卻片10a,稱為「第1冷卻片」,並將相對於燃燒室壁30的頂部而位於與燃燒室110為相反側(也就是凸輪室側)之冷卻片10b,稱為「第2冷卻片」。於本實施形態中,根據第8圖、第9圖及第10圖可知,複數個冷卻片10是以第1冷卻片10a的面積的合計大於第2冷卻片10b的面積的合計之方式而設置。 Here, the cooling fins 10a of the plurality of cooling fins 10 on the side of the combustion chamber 110 with respect to the top of the combustion chamber wall 30 are referred to as "first cooling fins" and will be opposed to the top of the combustion chamber wall 30. The cooling fin 10b located on the opposite side of the combustion chamber 110 (that is, on the cam chamber side) is referred to as a "second cooling fin". In the present embodiment, as shown in FIG. 8, FIG. 9, and FIG. 10, the plurality of cooling fins 10 are provided such that the total area of the first cooling fins 10a is larger than the total area of the second cooling fins 10b. .
於引擎101的運轉中,缸頭本體100中,相對於燃 燒室壁30的頂點部為燃燒室110側的區域,比相對於燃燒室壁30的頂點部與燃燒室110為相反側的區域,其溫度較高。因此,藉由使位於前者的區域中之第1冷卻片10a的面積的合計,大於位於後者的區域中之第2冷卻片10b的面積的合計,可有效地提高冷卻性。 In the operation of the engine 101, in the cylinder head body 100, relative to the combustion The apex portion of the blast chamber wall 30 is a region on the side of the combustion chamber 110, and the temperature is higher than a region on the opposite side of the apex portion of the combustion chamber wall 30 from the combustion chamber 110. Therefore, by making the total of the areas of the first cooling fins 10a in the region of the former larger than the total area of the second cooling fins 10b in the latter region, the cooling performance can be effectively improved.
又,於本實施形態中,如第10圖所示,當自相對於氣缸軸線L1與凸輪鏈室70為相反側來觀察時(當自第10圖中的垂直於紙面之方向來觀察時),複數個冷卻片10是以下述方式而設置:第1冷卻片10a的氣缸軸線L1側的端部10a1比第2冷卻片10b的氣缸軸線L1側的端部10b1更接近氣缸軸線L1。也就是說,第2冷卻片10b的端部10b1,比第1冷卻片10a的端部10a1更遠離氣缸軸線L1。藉此,可進一步增大冷卻空氣通道60的截面積。 Further, in the present embodiment, as shown in Fig. 10, when viewed from the side opposite to the cam chain chamber 70 with respect to the cylinder axis L1 (when viewed from the direction perpendicular to the paper surface in Fig. 10) The plurality of cooling fins 10 are provided such that the end portion 10a1 on the cylinder axis L1 side of the first cooling fin 10a is closer to the cylinder axis L1 than the end portion 10b1 on the cylinder axis L1 side of the second cooling fin 10b. In other words, the end portion 10b1 of the second cooling fin 10b is farther from the cylinder axis L1 than the end portion 10a1 of the first cooling fin 10a. Thereby, the cross-sectional area of the cooling air passage 60 can be further increased.
進而,於本實施形態中,如第10圖所示,冷卻空氣通道60的一部分是藉由排氣通道壁51所規定,該排氣通道壁51規定排氣通道50,並與凸輪室壁20以呈銳角之方式交叉。藉此,可獲得如下所述的優點。 Further, in the present embodiment, as shown in Fig. 10, a part of the cooling air passage 60 is defined by the exhaust passage wall 51 which defines the exhaust passage 50 and the cam chamber wall 20 Cross in an acute angle. Thereby, the advantages as described below can be obtained.
通常,在壓鑄時利用金屬模具來形成冷卻空氣通道的形狀的情況下,金屬模具的與冷卻空氣通道相對應之部分,具有比其他部分突出之形狀。具有此種突出之形狀之部分的前端,因熔融金屬的熱量而易於變得溫度較高。尤其是若前端有棱角,就可能會熔損。因此,一般而言,將前端設計成剖面為圓形。然而,如本實施形態般,藉由利用以與凸輪室壁20呈銳角之方式交叉之排氣通道壁51來規定冷卻空 氣通道60的一部分,可增大冷卻空氣通道60的截面積。此時,由於凸輪室壁20與排氣通道壁51的厚度均可較小,因此,可避免熔損的問題。 In general, in the case where the shape of the cooling air passage is formed by a metal mold at the time of die casting, the portion of the metal mold corresponding to the cooling air passage has a shape protruding from the other portions. The front end of the portion having such a protruding shape is liable to become higher in temperature due to the heat of the molten metal. In particular, if the front end has an angular shape, it may melt. Therefore, in general, the front end is designed to have a circular cross section. However, as in the present embodiment, the cooling space is defined by using the exhaust passage wall 51 that intersects the cam chamber wall 20 at an acute angle. A portion of the air passage 60 increases the cross-sectional area of the cooling air passage 60. At this time, since the thickness of the cam chamber wall 20 and the exhaust passage wall 51 can be small, the problem of melt loss can be avoided.
較佳為,凸輪室壁20具有2.5mm以下的厚度。藉由使凸輪室壁20的厚度為2.5mm以下,可更確實地防止金屬模具的棱角發生熔損。但若凸輪室壁20的厚度不足1.5mm,則無法充分獲得凸輪室109所要求的耐壓強度,且對由於應變而產生的變形應力之耐性有時會不足,因此,凸輪室壁20的厚度較佳為1.5mm以上。 Preferably, the cam chamber wall 20 has a thickness of 2.5 mm or less. By making the thickness of the cam chamber wall 20 2.5 mm or less, it is possible to more reliably prevent the corners of the mold from being melted. However, if the thickness of the cam chamber wall 20 is less than 1.5 mm, the pressure resistance required for the cam chamber 109 cannot be sufficiently obtained, and the resistance to deformation stress due to strain may be insufficient, and therefore, the thickness of the cam chamber wall 20 is obtained. It is preferably 1.5 mm or more.
又,於本實施形態中,由於缸頭本體100是藉由壓鑄而成形,因此,可縮小冷卻片10的厚度與節距,並可提高冷卻性。具體而言,如第14圖所示,當使複數個冷卻片10各自的前端部的厚度為t,並使複數個冷卻片10的節距為p時,可使各冷卻片10的前端部的厚度t為1.0mm以上且2.5mm以下,並以7.5mm以下的節距p來配置複數個冷卻片10。 Further, in the present embodiment, since the cylinder head main body 100 is formed by die casting, the thickness and pitch of the cooling fins 10 can be reduced, and the cooling property can be improved. Specifically, as shown in Fig. 14, when the thickness of each of the plurality of cooling fins 10 is t and the pitch of the plurality of cooling fins 10 is p, the front end portion of each of the cooling fins 10 can be made. The thickness t is 1.0 mm or more and 2.5 mm or less, and a plurality of cooling fins 10 are arranged at a pitch p of 7.5 mm or less.
較佳為,複數個冷卻片10各自具有2.0°以下的拔模斜度(拔模角度,draft angle)。藉由將拔模斜度減小為2.0°以下,由於可增大冷卻片10的根部之間的間隔,因此,可進一步提高冷卻性。但自易於脫模之觀點來看,複數個冷卻片10各自的拔模斜度較佳為1.0°以上。 Preferably, the plurality of cooling fins 10 each have a draft angle of 2.0° or less. By reducing the draft angle to 2.0 or less, since the interval between the root portions of the cooling fins 10 can be increased, the cooling property can be further improved. However, from the viewpoint of easy demolding, the draft angle of each of the plurality of cooling fins 10 is preferably 1.0 or more.
又,如第10圖所示,本實施形態中的缸頭本體100,進而具有肋(rib)90,該肋90設置於冷卻空氣通道60內,且連結燃燒室壁30與凸輪室壁20。藉由使肋90連結燃燒室壁30與凸輪室壁20,肋90可將燃燒室壁30的熱量傳達至凸輪 室壁20,而凸輪室109可使用潤滑油來進行冷卻,因此,可提高冷卻性。又,藉由將肋90配置於冷卻空氣通道60內,亦可獲得由冷卻空氣CA所產生的冷卻效果。 Further, as shown in Fig. 10, the cylinder head main body 100 of the present embodiment further has a rib 90 which is provided in the cooling air passage 60 and connects the combustion chamber wall 30 and the cam chamber wall 20. By joining the ribs 90 to the combustion chamber wall 30 and the cam chamber wall 20, the ribs 90 can transfer heat from the combustion chamber wall 30 to the cam. The chamber wall 20, and the cam chamber 109 can be cooled using lubricating oil, so that the cooling property can be improved. Further, by arranging the ribs 90 in the cooling air passage 60, the cooling effect by the cooling air CA can also be obtained.
再者,較佳為,肋90是沿著當缸頭本體100以壓鑄而成形時的起模方向而形成。因此,較佳為,肋90是沿著用以規定冷卻空氣通道60之壁部分(冷卻空氣通道壁)而形成。 Further, it is preferable that the rib 90 is formed along a die-off direction when the head body 100 is formed by die casting. Therefore, it is preferable that the rib 90 is formed along a wall portion (cooling air passage wall) for defining the cooling air passage 60.
又,較佳為,沿著正交於排氣通道50的軸線50x之 面之排氣通道50的剖面形狀大致為橢圓,且排氣通道50的出口50b的形狀,如第9圖所示,大致為真圓。由於排氣管142的剖面形狀一般大致為真圓,因此,藉由使排氣通道50的出口50b的形狀大致為真圓,可防止通道面積的急劇變化,並防止引擎101的性能降低。如上所述,由於排氣通道50是以隨著自入口側朝向出口側而遠離凸輪鏈室70遠離之方式延伸,因此,若沿著正交於軸線50x之面之排氣通道50的剖面形狀大致為真圓,則無法使排氣通道50的出口50b的形狀大致為真圓。藉由使沿著正交於軸線50x之面之排氣通道50的剖面形狀大致為橢圓,也就是說,藉由使沿著正交於軸線50x之面之排氣通道50的剖面形狀的真圓度,低於排氣通道50的出口50b的形狀的真圓度,可使排氣通道50的出口50b的形狀大致為真圓。 Further, preferably, along an axis 50x orthogonal to the exhaust passage 50 The cross-sectional shape of the surface exhaust passage 50 is substantially elliptical, and the shape of the outlet 50b of the exhaust passage 50, as shown in Fig. 9, is substantially a true circle. Since the cross-sectional shape of the exhaust pipe 142 is generally substantially round, by making the shape of the outlet 50b of the exhaust passage 50 substantially round, it is possible to prevent an abrupt change in the passage area and prevent the performance of the engine 101 from deteriorating. As described above, since the exhaust passage 50 extends away from the cam chain chamber 70 from the inlet side toward the outlet side, the cross-sectional shape of the exhaust passage 50 along the plane orthogonal to the axis 50x is obtained. If it is substantially round, the shape of the outlet 50b of the exhaust passage 50 cannot be made substantially round. By making the cross-sectional shape of the exhaust passage 50 along the plane orthogonal to the axis 50x substantially elliptical, that is, by making the cross-sectional shape of the exhaust passage 50 along the plane orthogonal to the axis 50x true The roundness, which is lower than the roundness of the shape of the outlet 50b of the exhaust passage 50, makes the shape of the outlet 50b of the exhaust passage 50 substantially round.
進而,亦較佳為,對規定冷卻空氣通道60和凸輪鏈室109之壁部、包含複數個冷卻片10之外側面,進行珠粒噴擊(shot blast)處理。利用由珠粒噴擊處理所實施的粗面化,而使與冷卻空氣CA接觸之面積增加,因此,可謀求進一步提高 冷卻性。又,亦可藉由珠粒噴擊處理,對冷卻空氣通道60進行毛邊去除。 Further, it is also preferable to perform a shot blast process on the wall portions of the predetermined cooling air passage 60 and the cam chain chamber 109 and the outer surfaces of the plurality of cooling fins 10. By using the roughening by the bead blasting treatment, the area in contact with the cooling air CA is increased, so that further improvement can be achieved. Cooling. Further, the cooling air passage 60 may be burred by the bead blasting treatment.
又,亦較佳為,設置自肋90延伸之冷卻片、或對肋90施加珠粒噴擊處理,以進一步提高冷卻性。 Further, it is also preferable to provide a cooling fin extending from the rib 90 or to apply a bead blasting treatment to the rib 90 to further improve the cooling property.
本發明的實施形態中的內燃機101,適合用於機車、ATV(All Terrain Vehicle)等各種跨坐型車輛。又,亦適合用於發電機等。 The internal combustion engine 101 according to the embodiment of the present invention is suitably used for various straddle type vehicles such as a locomotive and an ATV (All Terrain Vehicle). Also, it is also suitable for use in generators and the like.
依據本發明,提供一種氣冷式內燃機,該氣冷式內燃機具備缸頭本體,該缸頭本體具有擁有充分的截面積之冷卻空氣通道,且可藉由壓鑄較合適地成形。依據本發明的氣冷式內燃機,由於缸頭本體的冷卻性優異,因此,適合用於包括機車在內之各種跨坐型車輛。 According to the present invention, there is provided an air-cooled internal combustion engine having a cylinder head body having a cooling air passage having a sufficient cross-sectional area and which can be suitably formed by die casting. According to the air-cooled internal combustion engine of the present invention, since the cylinder head body is excellent in cooling property, it is suitable for use in various straddle type vehicles including a locomotive.
30‧‧‧燃料室壁 30‧‧‧fuel chamber wall
32‧‧‧塞孔 32‧‧‧ plug hole
40‧‧‧吸氣通道 40‧‧‧ Inhalation channel
40a‧‧‧吸氣口 40a‧‧‧ suction port
50‧‧‧排氣通道 50‧‧‧Exhaust passage
50a‧‧‧排氣口(排氣通道的入口) 50a‧‧‧Exhaust port (inlet of exhaust duct)
50x‧‧‧排氣通道的軸線 50x‧‧‧ axis of the exhaust passage
60a‧‧‧冷卻空氣通道的入口 60a‧‧‧Environment of the cooling air passage
60b‧‧‧冷卻空氣通道的出口 60b‧‧‧Exit of the cooling air passage
70‧‧‧凸輪鏈室 70‧‧‧Cam chain room
80‧‧‧帶頭螺栓凸座 80‧‧‧Leading bolt boss
80a、80b、80c、80d‧‧‧螺栓孔 80a, 80b, 80c, 80d‧‧‧ bolt holes
100‧‧‧缸頭本體 100‧‧‧ cylinder head body
13A-13A’‧‧‧線 Line 13A-13A’‧‧‧
L3‧‧‧連結螺栓孔80a和80b的中心之直線 L3‧‧‧ Straight line connecting the centers of bolt holes 80a and 80b
CA‧‧‧冷卻空氣 CA‧‧‧Cooling air
Claims (15)
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JP2012219305A JP2014070621A (en) | 2012-10-01 | 2012-10-01 | Air-cooled internal combustion engine and saddle type vehicle with the same |
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Publication Number | Publication Date |
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TW201418569A true TW201418569A (en) | 2014-05-16 |
TWI551774B TWI551774B (en) | 2016-10-01 |
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TW102135544A TWI551774B (en) | 2012-10-01 | 2013-10-01 | Air-cooling type internal combustion engine and saddled vehicle having the same |
Country Status (4)
Country | Link |
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EP (1) | EP2713033B1 (en) |
JP (1) | JP2014070621A (en) |
CN (1) | CN103711560B (en) |
TW (1) | TWI551774B (en) |
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JP6795641B2 (en) * | 2019-02-26 | 2020-12-02 | 本田技研工業株式会社 | Internal combustion engine for saddle-type vehicles |
CN111237077B (en) * | 2019-09-11 | 2024-04-16 | 浙江康思特动力机械有限公司 | Cylinder cover provided with multiple cooling air channels |
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KR100569164B1 (en) * | 2002-09-24 | 2006-04-07 | 혼다 기켄 고교 가부시키가이샤 | Air-cooled internal combustion engine |
JP2004116464A (en) | 2002-09-27 | 2004-04-15 | Honda Motor Co Ltd | Cylinder head of internal combustion engine |
EP2410164A3 (en) * | 2010-07-19 | 2012-10-10 | Kwang Yang Motor Co., Ltd. | Structure of cylinder head of air cooling engine |
JP5581196B2 (en) * | 2010-12-24 | 2014-08-27 | 川崎重工業株式会社 | Engine cooling system |
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2012
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EP2713033A1 (en) | 2014-04-02 |
EP2713033B1 (en) | 2018-11-07 |
CN103711560A (en) | 2014-04-09 |
CN103711560B (en) | 2017-09-22 |
TWI551774B (en) | 2016-10-01 |
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