Cylinder head and water jacket core for internal combustion engine

Abstract

A cylinder head includes a cover plate body including a first exhaust valve port, a second exhaust valve port, and a spark plug bore extending between opposite top sides of a combustion cover plate and the cover plate body. The cover plate body further includes a water jacket extending between the first and second exhaust valve ports and the spark plug bore. The water jacket has a bottom side that forms the thickness of the cover plate body between the combustion cover plate and the bottom side of the water jacket. The thickness varies between the first and second exhaust valve ports and the spark plug bore to improve cooling of the combustion cover plate while providing structural support for the cover plate around the spark plug bore.

Description

Technical Field

[0001] The present disclosure relates to internal combustion engines, and more particularly to cylinder heads and water jacket cores for internal combustion engines. Background Art

[0002] There is a need for continued improvement in the development of internal combustion engines that use low carbon fuels. For example, gaseous fuels such as natural gas and hydrogen provide reduced greenhouse gas emissions and a lower carbon footprint. However, during engine operation, gaseous fuels can result in higher combustion temperatures. These higher temperatures can negatively impact the engine's supporting structures, such as the cylinder head, due to thermomechanical fatigue. Therefore, there is a need for further improvement in this area of ​​the technology to accommodate gaseous fuels. Summary of the invention

[0003] In an embodiment disclosed herein, a cylinder head for an internal combustion engine is provided. The cylinder head includes an elongated body extending between a combustion deck and a top side opposite to the combustion deck. The elongated body includes an intake side and an exhaust side opposite to the intake side. The cylinder head includes a first exhaust valve port and a second exhaust valve port, each extending through the body. The first exhaust valve port and the second exhaust valve port extend between the combustion deck and the top side of the body and open at the combustion deck and the top side of the body. The cylinder head also includes a spark plug hole between the first exhaust valve port and the second exhaust valve port. The spark plug hole extends through the body and opens at the top side of the combustion deck and the body. The cylinder head also includes a water jacket located in the body. The water jacket includes a bottom side oriented toward the combustion deck, the bottom side extending between the first exhaust valve port and the second exhaust valve port and the spark plug hole. The bottom side of the water jacket is configured to provide a varying cover plate thickness from the combustion deck to the bottom side of the water jacket between the first exhaust valve port and the second exhaust valve port and the spark plug hole.

[0004] In another embodiment disclosed herein, a water jacket core for forming a water jacket in a cylinder head of an internal combustion engine is provided. The water jacket core includes a core body extending between a bottom side oriented toward a combustion cover plate of the cylinder head and an upper side opposite to the bottom side. The bottom side of the core body forms the bottom side of the water jacket of the cylinder head. The core body extends around a first exhaust valve port channel and a second exhaust valve port channel, and the first exhaust valve port channel and the second exhaust valve port channel extend from the upper side to the bottom side along the core body. The core body also includes a spark plug hole groove between the first exhaust valve port channel and the second exhaust valve port channel. The spark plug hole groove extends from the upper side to the bottom side along the core body. The portion of the bottom side of the core body extending between the first exhaust valve port channel and the second exhaust valve port channel and the spark plug hole groove is configured to provide the cylinder head with a varying cover plate thickness from the combustion cover plate to the bottom side of the water jacket.

[0005] While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The above and other features of the present disclosure and the manner of obtaining them will become more apparent, and the present disclosure will be better understood, by referring to the following description of the embodiments of the present disclosure made in conjunction with the accompanying drawings, in which:

[0007] Figure 1 is a top view of an exemplary cylinder head according to an embodiment of the present disclosure.

[0008] Figure 2 yes Figure 1 A front view of the intake side of a cylinder head and a schematic diagram of an engine block to which the cylinder head may be mounted.

[0009] Figure 3 yes Figure 1 A perspective view of a portion of a cylinder head looking toward the combustion cover plate.

[0010] Figure 4 It is Figure 3 A plan view of the combustion cover plate as seen from the parts of this portion of the cylinder head.

[0011] Figure 5 yes Figure 4 A perspective view of this part of the cylinder head.

[0012] Figure 6 It is Figure 1 A plan view of the parts of the water jacket core of the cylinder head viewed from the combustion cover plate side.

[0013] Figure 7 yes Figure 6 A perspective view of a portion of this part of the water jacket core.

[0014] Figure 8 yes Figure 7 An enlarged perspective view of this portion of this part of the water jacket core.

[0015] Fig. 9 yes Figure 1 A cross-sectional view of a cylinder head in a region configured to receive a spark plug.

[0016] Fig.10 is another cross-sectional view of a region of the cylinder head that is configured to receive a spark plug.

[0017] Although the present invention may have various modifications and alternative forms, specific embodiments have been shown by way of example in the accompanying drawings and are described in detail below. However, the purpose is not to limit the present invention to the specific embodiments described. On the contrary, the present invention is intended to cover all modifications, equivalents and substitutes falling within the scope of the invention defined by the appended claims. DETAILED DESCRIPTION

[0018] In the following detailed description, reference is made to the accompanying drawings which form a part thereof, and in the accompanying drawings, specific embodiments in which the present invention may be practiced are shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention, and it should be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Therefore, the following detailed description should not be considered restrictive, and the scope of the present invention is defined by the appended claims and their equivalents.

[0019] refer to Figures 1 to 10 , a cylinder head 100 for an internal combustion engine 104 is provided. The cylinder head 100 includes an elongated body 110 extending between a combustion cover plate 112 and a top side 114 opposite the combustion cover plate 112. The elongated body 110 includes an intake side 116 and an exhaust side 118 opposite the intake side 116. The cylinder head 100 includes a first exhaust valve port 146 and a second exhaust valve port 148 each extending through the body 110. The first exhaust valve port 146 and the second exhaust valve port 148 extend between the combustion cover plate 112 and the top side 114 of the body 110 and open at the combustion cover plate and the top side of the body. The cylinder head 100 also includes a spark plug hole 150 located between the first exhaust valve port 146 and the second exhaust valve port 148. The spark plug hole 150 extends through the body 110 and opens at the combustion cover plate 112 and the top side 114 of the body 102. The cylinder head 100 also includes a water jacket 156 located within the body 102. The water jacket 156 includes a bottom side 158 oriented toward the combustion cover plate 112 that extends between the first and second exhaust valve ports 146, 148 and the spark plug holes 150. The bottom side 158 of the water jacket 156 is configured to provide a varying cover plate thickness from the combustion cover plate 112 to the bottom side 158 of the water jacket 156 between the first and second exhaust valve ports 146, 148 and the spark plug holes 150.

[0020] In another embodiment disclosed herein, a water jacket core 200 for forming a water jacket 156 in a cylinder head 100 of an internal combustion engine 104 is provided. The water jacket core 200 includes a core body 202 extending between a bottom side 204 oriented toward a combustion cover plate 112 of the cylinder head 100 and an upper side 206 opposite the bottom side 204. The bottom side 204 of the core body 202 forms the bottom side 158 of the water jacket 156 of the cylinder head 100. The core body 202 extends around a first exhaust valve port passage 208 and a second exhaust valve port passage 210, and the first exhaust valve port passage 208 and the second exhaust valve port passage 210 extend along the core body 202 from the upper side 206 to the bottom side 204. The core body 202 also includes a spark plug hole recess 212 located between the first exhaust valve port passage 208 and the second exhaust valve port passage 210. The spark plug hole recess 212 extends along the core body 202 from the upper side 206 to the bottom side 204. A portion 214 of the bottom side 204 of the core body 202 extending between the first exhaust valve port passage 208 and the second exhaust valve port passage 210 and the spark plug hole recess 212 is configured to provide the cylinder head 100 with a varying cover plate thickness from the combustion cover plate 112 to the bottom side 158 of the water jacket 156.

[0021] Figure 1 to Figure 2 A cylinder head 100 is shown mounted to an engine block 102 as part of a subassembly of an internal combustion engine 104. The cylinder head 100 includes an elongated body 110 extending from a bottom side or combustion cover plate 112 to an opposite top side 114. The combustion cover plate 112 is mounted on top of the engine block 102 with the top side 114 facing away from the engine block 102. The body 110 also includes an intake side 116 and an opposite exhaust side 118. The combustion cover plate 112, the top side 114, the intake side 116, and the exhaust side 118 extend between opposite ends 120, 122 of the body 110.

[0022] The cylinder head 100 includes various ports, holes and passages extending from the top side 114 to the combustion cover plate 112 to accommodate valves, spark plugs, injectors and other components that are usually mounted to the cylinder head. In the illustrated embodiment, the first opening group 124 of the cylinder head 100 is associated with the first combustion chamber 108 of the internal combustion engine 104. The cylinder head 100 includes one or more additional identical opening groups 126, 138, 130, 132, 134 for one or more additional combustion chambers 108 of the internal combustion engine 104. The following discussion is directed to the construction of the cylinder head 110 around the first opening group 124, and it should be understood that other opening groups 126, 128, 130, 132, 134 can be similarly constructed. In addition, although the six combustion chambers 108 are shown as having six associated opening groups, the present disclosure can be applied to the cylinder head configured for an engine with any number of combustion chambers.

[0023] As shown in the first opening group 124, the intake side 116 includes a pair of intake ports 136, 138 for each of the combustion chambers 108 to provide an intake flow through the intake valve ports 140, 142 of the cylinder head 100. The exhaust side 118 includes at least one exhaust port 144 for each combustion chamber 108 to receive exhaust gas from the exhaust valve ports 146, 148. In an embodiment, the exhaust gas is produced in the combustion chamber 108 by the combustion of a mixture of the intake flow initiated by the spark plug in the spark plug hole 150 and the fuel from the fuel injector in the injector port 152. The other opening groups 126, 128, 130, 132, 134 can be similarly configured with intake ports, intake valve ports, exhaust valve ports, exhaust ports, spark plug holes and injector ports. In an embodiment, the cylinder head 100 is configured to operate with a gaseous fuel such as natural gas. Other gaseous fuels, such as hydrogen fuel or propane fuel, can also be considered.

[0024] In the illustrated embodiment, the intake ports 136, 138 of each opening group 124, 126, 128, 130, 132, 134 open at the side wall defined by the cylinder head 110 along the intake side 116. Each intake port 136, 138 can be separated from adjacent intake ports by a vertical wall section 137 between adjacent intake ports. Therefore, in the embodiment, the cylinder head 100 is not provided with an intake box, and the intake ports 136, 138 provide a separate entrance to each intake valve port 140, 142. This allows high swirl characteristics to be imparted through each intake port 136, 138 to improve the mixing of the fuel in the combustion chamber 108. In other embodiments, an intake box may be provided.

[0025] Further references Figures 3 to 5 , the cylinder head body 102 includes a lower water jacket 154 and an upper water jacket 156 formed therein. The lower water jacket 154 is primarily formed around the exhaust valve ports 146, 148 and the exhaust port 144 adjacent the combustion cover plate 112. The upper water jacket 156 is generally located above the lower water jacket 154 and extends near or around the intake valve ports 140, 142 and the exhaust valve ports 146, 148. In addition, as further discussed below and Figures 9 and 10 As shown, the upper water jacket 156 includes an exhaust valve port region 162 located on the exhaust side of the spark plug hole 150, which extends from the bottom side 158 of the water jacket 156 adjacent to the combustion cover plate 112 to the upper side 160 adjacent to the top side 114 of the body 110. The exhaust valve port region 162 further extends between the intake valve ports 140, 142 and the exhaust valve ports 146, 148, and between the spark plug hole 150 and the exhaust valve ports 146, 148.

[0026] At the exhaust valve port region 162, the bottom side 158 of the water jacket 156 is configured to provide a varying cover plate thickness t1 from the combustion cover plate 112 to the bottom side 158 of the water jacket 156 between the first exhaust valve port 146 and the second exhaust valve port 148 and the spark plug hole 150. This varying cover plate thickness allows the bottom side 158 of the water jacket 156 to be placed adjacent the combustion cover plate 112 to provide increased cooling of the combustion cover plate 112 while also configuring the body 110 to provide structural support at a targeted location between the spark plug hole 150 and each of the exhaust valve ports 146, 148. In an embodiment, the varying cover plate thickness t1 is formed in the exhaust valve port region 162 by the concave sections 164, 166 of the water jacket 156 on the bottom side 158 of the water jacket 156.

[0027] refer to Figures 6 to 8 The configuration of the bottom side 158 of the water jacket 156 may be further understood with reference to a water jacket core 200 that is used to form the water jacket 156 within the body 110 of the cylinder head 100 during manufacture of the cylinder head 100 . Figures 6 to 8 Only a portion of the water jacket core 200 is shown, and it should be understood that the water jacket core 200 can be constructed into one or more parts to form an upper water jacket extending along each of the opening groups 124, 126, 128, 130, 132, 134.

[0028] The water jacket core 200 includes a core body 202 extending between a bottom side 204 oriented toward the combustion cover plate 112 of the cylinder head 100 and an upper side 206 opposite the bottom side 204. Once the water jacket core 200 is removed from the cylinder head 100 during manufacturing, the bottom side 204 of the core body 202 forms the bottom side 158 of the water jacket 156 of the cylinder head 100.

[0029] The core body 202 extends around the first exhaust valve port channel 208 and the second exhaust valve port channel 210. The first exhaust valve port channel 208 and the second exhaust valve port channel 210 extend along the core body 202 from the upper side 206 to the bottom side 204. The core body 202 also includes a spark plug hole groove 212 located between the first exhaust valve port channel 208 and the second exhaust valve port channel 210. The spark plug hole groove 212 extends along the core body 204 from the upper side 206 to the bottom side 204. In an embodiment, the spark plug hole groove 212 is semicircular to provide space for forming the water jacket 156 between the spark plug hole 150 and the exhaust valve ports 146, 148 without extending around the intake side of the spark plug hole 150.

[0030] A portion 214 of the bottom side 204 of the body 202 of the water jacket core 200 extends between the first and second exhaust valve port passages 208 and 210 and the spark plug hole recess 212. The portion 214 is configured to provide the cylinder head 100 with a varying cover plate thickness t from the combustion cover plate 112 to the bottom side 158 of the water jacket 156.

[0031] In an embodiment, the portion 214 of the bottom side 204 of the water jacket core 200 includes a first concave section 216 between the first exhaust valve port passage 208 and the spark plug hole recess 212. The portion 214 also includes a second concave section 218 between the second exhaust valve port passage 210 and the spark plug hole recess 212. In addition, the portion 214 of the bottom side 204 includes a mid-planar section 220 extending from the first concave section 216 to the second concave section 218. The mid-planar section 220 further extends between the first exhaust valve port passage 208 and the second exhaust valve port passage 210.

[0032] In an embodiment, the portion 214 of the bottom side 204 of the core body 202 includes outer planar sections 222, 224 extending outwardly from respective ones of the first concave section 216 and the second concave section 218 opposite the middle planar section 220. In an embodiment, the first concave section 216 curves concavely from the outer planar section 222 to the middle planar section 220, and the second concave section 218 curves concavely from the outer planar section 224 to the middle planar section 220. The concave curvature of the concave sections 216, 218 forms separate valleys in the bottom 204 of the core body 202, which creates a thickened portion of the body 110 of the cylinder head 100 at the bridge between the spark plug hole 150 and each exhaust valve port 146, 148.

[0033] In an embodiment, the core body 202 includes a first side surface 226 extending from the bottom side 204 along the first exhaust valve port passage 208 and the second exhaust valve port passage 210 toward the upper side 206 of the core body 202. The core body 202 also includes a second side surface 228 extending from the bottom side 204 along the spark plug hole groove 212. In an embodiment, the second side surface 228 is convexly curved toward the spark plug hole groove 212 adjacent to the bottom side 204 to form a bulbous region 168 of the water jacket 156 surrounding the spark plug hole 150, as shown. Figures 9 and 10 In an embodiment, the bulbous region 168 is wider than a portion of the water jacket 156 that extends from the bulbous region toward the upper side 160 of the water jacket 156 .

[0034] Thus, when the water jacket core 200 is removed, the water jacket 156 includes a first sidewall 170 extending from the bottom side 158 of the water jacket 156 along the first exhaust valve port 146 and the second exhaust valve port 148 toward the top side 114 of the cylinder head 100. The water jacket 156 also includes a second sidewall 172 extending from the bottom side 158 along the spark plug hole 150. The second sidewall 172 is concavely curved toward the spark plug hole 150 adjacent the bottom side 158 to form a bulbous area 168 around the exhaust side of the spark plug hole 150 along the bottom side 158 of the water jacket 156.

[0035] In an embodiment, the body 110 of the cylinder head 100 has a wall thickness t2 between the spark plug hole 150 and the second side wall 172 of the water jacket 156 in the bulbous region 168. In an embodiment, the wall thickness t2 provides a minimum thickness of less than about 6 mm to enhance cooling around the spark plug at or near the combustion cover plate 112.

[0036] In the embodiment, the concave sections 164, 166 are formed by the concave sections 216, 218 of the water jacket core 200. Therefore, the first concave section 216 forms the first concave section 164 having a concave curvature between the first exhaust valve port 146 and the spark plug hole 150 on the bottom side 158 of the water jacket 156. In addition, the second concave section 218 forms the second concave section 166 having a concave curvature between the second exhaust valve port 148 and the spark plug hole 150 on the bottom side 158 of the water jacket 156.

[0037] In addition, the middle planar section 220 of the water jacket core 200 forms the middle planar section 174 extending between the first concave section 164 and the second concave section 166 on the bottom side 158 of the water jacket 156. The middle planar section 174 is also formed to extend at least partially in the area between the first exhaust valve port 146 and the second exhaust valve port 148.

[0038] In an embodiment, the outer planar section 222 of the water jacket core 200 forms the first outer planar section 176 along the bottom side 158 of the water jacket 156, and the outer planar section 224 of the water jacket core 200 forms the second outer planar section 178 along the bottom side 158 of the water jacket 156. The outer planar sections 176, 178 extend outwardly from respective ones of the first concave curved section 164 and the second concave curved section 166 opposite the intermediate planar section 174.

[0039] In an embodiment, the concave sections 164, 166 form a maximum cover plate thickness t1 of about 12 mm from the combustion cover plate 112 to the bottom 158 of the water jacket 156 in the exhaust valve port area 162. In an embodiment, the middle planar section 174 and / or the outer planar sections 176, 178 form a maximum cover plate thickness t1 of about 10 mm from the combustion cover plate 112 to the bottom 158 of the water jacket 156. In an embodiment, the nominal cover plate thickness of the combustion cover plate 112 outside the exhaust valve port area 162 is 12 mm.

[0040] The cover plate thickness t1 places the water jacket 156 close to the combustion cover plate 112 in the area with the minimum thickness to provide cooling of the combustion cover plate in the exhaust valve port area 162 around the spark plug hole 150, while the area with the maximum cover plate thickness t1 provides increased cover plate thickness in the critical area between the exhaust valve ports 146, 148 and the spark plug hole 150 to resist thermo-mechanical fatigue in the high temperature area of ​​the cylinder head 100.

[0041] In one embodiment of the cylinder head 100, the water jacket 156 includes a first bridge portion 180 located between the spark plug hole 150 and the first exhaust valve port 146, and a second bridge portion 182 located between the spark plug hole 150 and the second exhaust valve port 148. The water jacket 156 also includes a nose portion 184 located between the first bridge portion 180 and the second bridge portion 182. The nose portion 184 extends from the spark plug hole 150 between the first exhaust valve port 146 and the second exhaust valve port 148.

[0042] In an embodiment, the varying cover plate thickness along the bottom 158 of the water jacket 156 is formed by a first concave section 164 along a first bridge portion 180 of the bottom side 158 of the water jacket 156 and a second concave section 166 along a second bridge portion 182 of the bottom side 158 of the water jacket 156. A mid-planar section 174 on the bottom side 158 of the water jacket 156 provides a minimum cover plate thickness along the nose portion 184.

[0043] Various aspects of the present disclosure are covered. According to one aspect, a cylinder head for an internal combustion engine is provided. The cylinder head includes an elongated body extending between a combustion cover plate and a top side opposite to the combustion cover plate. The elongated body includes an intake side and an exhaust side opposite to the intake side. The cylinder head also includes a first exhaust valve port and a second exhaust valve port, each extending through the body. The first exhaust valve port and the second exhaust valve port extend between the combustion cover plate and the top side of the body and open at the combustion cover plate and the top side of the body. The cylinder head also includes a spark plug hole between the first exhaust valve port and the second exhaust valve port. The spark plug hole extends through the body and opens at the combustion cover plate and the top side of the body. The cylinder head also includes a water jacket located within the body. The water jacket includes a bottom side oriented toward the combustion cover plate, the bottom side extending between the first exhaust valve port and the second exhaust valve port and the spark plug hole. The bottom side of the water jacket is configured to provide a varying cover plate thickness from the combustion cover plate to the bottom side of the water jacket between the first exhaust valve port and the second exhaust valve port and the spark plug hole.

[0044] In an embodiment, the varying cover plate thickness is formed by a concave section of the water jacket on the bottom side of the water jacket.

[0045] In another embodiment, the concave section includes: a first concave curved section located between the first exhaust valve port and the spark plug hole on the bottom side of the water jacket; and a second concave curved section located between the second exhaust valve port and the spark plug hole on the bottom side of the water jacket.

[0046] In another embodiment, the bottom side of the water jacket includes a mid-planar section extending between the first concave curved section and the second concave curved section. The mid-planar section extends between the first exhaust valve port and the second exhaust valve port.

[0047] In another embodiment, the concave curved section forms a cover plate thickness of about 12 millimeters and the mid-planar section forms a cover plate thickness of about 10 millimeters.

[0048] In another embodiment, the bottom side of the water jacket includes outer planar sections extending outwardly from respective ones of the first and second concavely curved sections opposite the intermediate planar section.

[0049] In an embodiment, the water jacket includes: a first bridge portion, the first bridge portion is located between the spark plug hole and the first exhaust valve port; a second bridge portion, the second bridge portion is located between the spark plug hole and the second exhaust valve port; and a nose portion, the nose portion is located between the first bridge portion and the second bridge portion. The nose portion extends from the spark plug hole between the first exhaust valve port and the second exhaust valve port.

[0050] In another embodiment, the varying cover plate thickness is formed by: a first concave section along a first bridging portion of the bottom side of the water jacket; a second concave section along a second bridging portion of the bottom side of the water jacket; and a mid-planar section along the nose portion on the bottom side.

[0051] In an embodiment, the cylinder head includes a second water jacket extending along a side of the first exhaust valve port and the second exhaust valve port opposite the water jacket.

[0052] In an embodiment, the water jacket includes: a first side wall extending from a bottom side along a first exhaust valve port and a second exhaust valve port toward a top side of the cylinder head; and a second side wall extending from the bottom side along a spark plug hole. The second side wall is concavely curved toward the spark plug hole adjacent to the bottom side to form a spherical area around the spark plug hole along the bottom side of the water jacket.

[0053] In another embodiment, the body of the cylinder head has a wall thickness in the bulbous region between the spark plug hole and the second side wall of the water jacket, and the wall thickness is less than about 6 millimeters.

[0054] In an embodiment, the cylinder head includes a first intake valve port and a second intake valve port, each extending through the body on a side of the spark plug hole opposite the first exhaust valve port and the second exhaust valve port. The first intake valve port and the second intake valve port extend between the combustion cover plate and the top side of the body and open at the combustion cover plate and the top side of the body.

[0055] In another embodiment, the first intake valve port, the second intake valve port, the first exhaust valve port, the second exhaust valve port and the spark plug hole form a first opening group of the cylinder head, which is associated with a first combustion chamber of the internal combustion engine. The cylinder head includes one or more additional identical opening groups for one or more additional combustion chambers of the internal combustion engine.

[0056] According to another aspect, a water jacket core for forming a water jacket in a cylinder head of an internal combustion engine is provided. The water jacket core includes a core body extending between a bottom side oriented toward a combustion cover plate of the cylinder head and an upper side opposite to the bottom side. The bottom side of the core body forms the bottom side of the water jacket of the cylinder head. The core body extends around a first exhaust valve port channel and a second exhaust valve port channel. The first exhaust valve port channel and the second exhaust valve port channel extend from the upper side to the bottom side along the core body. The core body includes a spark plug hole groove located between the first exhaust valve port channel and the second exhaust valve port channel. The spark plug hole groove extends from the upper side to the bottom side along the core body. The portion of the bottom side of the core body extending between the first exhaust valve port channel and the second exhaust valve port channel and the spark plug hole groove is configured to provide the cylinder head with a varying cover plate thickness from the combustion cover plate to the bottom side of the water jacket.

[0057] In an embodiment, the bottom side portion of the core body includes a first concave section located between the first exhaust valve port passage and the spark plug hole groove and a second concave section located between the second exhaust valve port passage and the spark plug hole groove.

[0058] In another embodiment, the portion of the bottom side of the core body includes a mid-planar section extending from the first concave section to the second concave section. The mid-planar section further extends between the first exhaust valve port channel and the second exhaust valve port channel.

[0059] In another embodiment, the bottom side of the core body includes outer planar sections extending outwardly from respective ones of the first and second concave sections opposite the intermediate planar section.

[0060] In another embodiment, the first concave section curves concavely from one of the outer planar sections to the middle planar section, and the second concave section curves concavely from the other outer planar section to the middle planar section.

[0061] In an embodiment, the spark plug hole recess is semi-circular.

[0062] In an embodiment, the core body includes: a first side surface extending from the bottom side along the first exhaust valve port passage and the second exhaust valve port passage toward the upper portion of the core body; and a second side surface extending from the bottom side along the spark plug hole groove. The second side surface is convexly curved toward the spark plug hole groove adjacent to the bottom side to form a spherical area of ​​the water jacket surrounding the spark plug hole.

[0063] It should be understood that the above description is intended to be illustrative and not restrictive. After reading and understanding the above description, many other embodiments will be apparent to those skilled in the art. For example, it is conceivable that the features described in conjunction with one embodiment are optionally used as a supplement or replacement for the features described in conjunction with another embodiment. Therefore, the scope of the present invention should be determined by reference to the attached claims and the full scope to which such claims are entitled.

Claims

1. A cylinder head for an internal combustion engine, the cylinder head comprising: an elongated body extending between a combustion cover plate and a top side opposite the combustion cover plate, the elongated body including an intake side and an exhaust side opposite the intake side; a first exhaust valve port and a second exhaust valve port, each of the first exhaust valve port and the second exhaust valve port extending through the body, the first exhaust valve port and the second exhaust valve port extending between the combustion cover plate and the top side of the body and opening at the combustion cover plate and the top side of the body; a spark plug hole located between the first exhaust valve port and the second exhaust valve port, the spark plug hole extending through the body and opening at the combustion cover plate and at the top side of the body; as well as a water jacket within the body, the water jacket including a bottom side oriented toward the combustion cover plate, the bottom side extending between the first and second exhaust valve ports and the spark plug hole, the bottom side of the water jacket being configured to provide a varying cover plate thickness from the combustion cover plate to the bottom side of the water jacket between the first and second exhaust valve ports and the spark plug hole. 2 . The cylinder head of claim 1 , wherein the varying cover plate thickness is formed by a concave section of the water jacket on the bottom side of the water jacket.

3. The cylinder head of claim 2, wherein the concave section comprises: a first concave curved section located on the bottom side of the water jacket between the first exhaust valve port and the spark plug hole; as well as A second concave curved section is located on the bottom side of the water jacket between the second exhaust valve port and the spark plug hole.

4. The cylinder head of claim 3, wherein the bottom side of the water jacket includes a mid-planar section extending between the first and second concavely curved sections, the mid-planar section extending between the first and second exhaust valve ports.

5. The cylinder head of claim 4, wherein the concave curved section forms a cover plate thickness of approximately 12 millimeters and the mid-planar section forms a cover plate thickness of approximately 10 millimeters.

6. The cylinder head of claim 4, wherein the bottom side of the water jacket includes an outer planar section extending outwardly from respective ones of the first and second concavely curved sections opposite the intermediate planar section.

7. The cylinder head according to claim 1, wherein the water jacket comprises: a first bridging portion, the first bridging portion being located between the spark plug hole and the first exhaust valve port; a second bridge portion, the second bridge portion being located between the spark plug hole and the second exhaust valve port; as well as A nose portion is located between the first bridge portion and the second bridge portion, the nose portion extending from the spark plug hole between the first exhaust valve port and the second exhaust valve port.

8. The cylinder head of claim 7, wherein the varying cover plate thickness is formed by: a first concave section of the bottom side of the water jacket along the first bridging portion; a second concave section of the bottom side of the water jacket along the second bridging portion; as well as and a mid-planar section along the nose portion on the bottom side.

9. The cylinder head of claim 1, further comprising a second water jacket extending along sides of the first exhaust valve port and the second exhaust valve port opposite to the water jacket.

10. The cylinder head of claim 1, wherein the water jacket comprises: a first side wall extending from the bottom side along the first exhaust valve port and the second exhaust valve port toward the top side of the cylinder head; as well as A second side wall extends from the bottom side along the spark plug hole, wherein the second side wall is concavely curved toward the spark plug hole adjacent to the bottom side to form a bulbous region around the spark plug hole along the bottom side of the water jacket.

11. The cylinder head of claim 10, wherein the body of the cylinder head has a wall thickness in the bulbous region between the spark plug hole and the second sidewall of the water jacket, and the wall thickness is less than about 6 millimeters.

12. The cylinder head according to claim 1 further includes a first intake valve port and a second intake valve port, wherein the first intake valve port and the second intake valve port each extend through the body on a side of the spark plug hole opposite to the first exhaust valve port and the second exhaust valve port, and the first intake valve port and the second intake valve port extend between the combustion cover plate and the top side of the body and open at the combustion cover plate and the top side of the body.

13. The cylinder head of claim 12, wherein the first intake valve port, the second intake valve port, the first exhaust valve port, the second exhaust valve port and the spark plug hole form a first opening group of the cylinder head, the first opening group is associated with a first combustion chamber of the internal combustion engine, and the cylinder head includes one or more additional identical opening groups for one or more additional combustion chambers of the internal combustion engine.

14. A water jacket core for forming a water jacket in a cylinder head of an internal combustion engine, the water jacket core comprising: a core body extending between a bottom side oriented toward a combustion cover plate of the cylinder head and an upper side opposite to the bottom side, the bottom side of the core body forming a bottom side of the water jacket of the cylinder head; the core body extending around a first exhaust valve port channel and a second exhaust valve port channel, the first exhaust valve port channel and the second exhaust valve port channel extending along the core body from the upper side to the bottom side; the core body including a spark plug hole recess between the first exhaust valve port passage and the second exhaust valve port passage, the spark plug hole recess extending along the core body from the upper side to the bottom side; and Portions of the bottom side of the core body extending between the first and second exhaust valve port passages and the spark plug hole recess are configured to provide the cylinder head with a varying cover plate thickness from the combustion cover plate to the bottom side of the water jacket.

15. The water jacket core of claim 14, wherein the portion of the bottom side of the core body comprises: a first concave section, the first concave section being located between the first exhaust valve port passage and the spark plug hole groove; as well as A second concave section is located between the second exhaust valve port passage and the spark plug hole groove.

16. The water jacket core of claim 15, wherein the portion of the bottom side of the core body includes a mid-planar section extending from the first concave section to the second concave section, the mid-planar section further extending between the first exhaust valve port passage and the second exhaust valve port passage.

17. The water jacket core of claim 16, wherein the bottom side of the core body includes an outer planar section extending outwardly from respective ones of the first and second concave sections opposite the intermediate planar section.

18. The water jacket core according to claim 17, wherein: The first concave section curves concavely from one of the outer planar sections to the intermediate planar section; and The second concave section is concavely curved from the other outer planar section toward the middle planar section.

19. The water jacket core of claim 14, wherein said spark plug hole recess is semi-circular.

20. The water jacket core of claim 14, wherein the core body comprises: a first side surface extending from the bottom side toward an upper portion of the core body along the first exhaust valve port passage and the second exhaust valve port passage; as well as A second side surface extends from the bottom side along the spark plug hole groove, wherein the second side surface is convexly curved toward the spark plug hole groove adjacent to the bottom side to form a spherical region of the water jacket surrounding the spark plug hole.

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