Abstract: A cooling structure of a water-cooled two-cycle parallel multicylinder engine includes: an exhaust port in a cylinder block; an air intake port disposed in a crankcase below the exhaust port; a water pump disposed in the crankcase in an opposite side of the exhaust port; a first cooling water passage introducing cooling water discharged from the water pump to a cooling water jacket of a cylinder head; and a second cooling water passage introducing a part of the cooling water discharged from the water pump to a cooling water jacket below the exhaust port, the second cooling water passage being provided in the crankcase.

Abstract: A water-cooled internal combustion engine has a cylinder head 21 provided with a cylinder head water jacket Jh through which cooling water flows. The cylinder head water jacket Jh includes a combustion chamber water jacket 70 surrounding combustion chambers 26 and an exhaust passage water jacket 71 around an exhaust manifold passage 38. The exhaust gas discharged from the combustion chambers 26 through exhaust ports 28 flows through the exhaust manifold passage. The exhaust passage water jacket 71 is divided into an upstream water jacket 72a and a downstream water jacket 72b by a partition wall 75. The cooling water flows from both the upstream water jacket 72a and the downstream water jacket 72a into the combustion chamber water jacket 70. Equality in temperature between a combustion chamber wall and an exhaust passage wall is improved and the cylinder head 21 is heated in a uniform temperature distribution.

Abstract: Provided is a cylinder head including a head casting defining a plurality of exhaust ports. A tuned exhaust manifold is internally defined by the head casting. The tuned exhaust manifold includes a plurality of exhaust runners in communication with the plurality of exhaust ports and a collector volume in communication with the plurality of exhaust runners. Each of the plurality of exhaust ports and each of the plurality of exhaust runners are substantially oriented or directed toward the collector volume. Additionally, the head casting defines a main cooling jacket operable to cool the head casting. The head casting also defines an upper and lower cooling jacket disposed in heat exchange relation to the tuned exhaust manifold. The cylinder head casting may include integral spark plug tubes and cam drive case. Additionally, the cooling jackets may have a series coolant flow pattern or a parallel coolant flow pattern.

Abstract: A pair of exhaust ports (4, 4) have flat portions (9, 9) formed on respective inner peripheral surfaces thereof and facing in directions opposite to each other. An intervening cooling water passage (14) is formed between the flat portions (9, 9) when a cylinder head (1) is cast.

Abstract: An internal combustion engine cylinder head unit includes a number of gas flow ports extending upwardly from a fire deck. A common coolant passage extends between adjacent ones of the gas flow ports. A first coolant flow director includes a flow splitter extending downwardly into the common coolant passage so as to cause a coolant flow within the common coolant passage to remain attached upon an upper surface of the fire deck between adjacent ports. A second coolant passage runs about a radially outboard portion of the cylinder head unit, and flow in this passage is directed by a truncated bulk flow displacer extending from a rear wall of the second coolant flow passage. The second flow director causes the impingement of coolant upon both an upper surface of the fire deck and upon an outboard portion of at least one of the cylinder ports.

Abstract: In a method for cooling an internal combustion engine, in particular in/on a motor vehicle, it is possible for individual components of the internal combustion engine to be cooled individually, for example a cylinder head and/or a cylinder block, by what is known as a split cooling system. In order to improve the cooling of the components, it is proposed to control the cooling of at least one of the components adaptively.

Abstract: In some aspects of the invention the invention will relate to conversion of an existing VW air cooled engine to liquid cooling, and in still further aspects it will relate to the design of a water jacket to maximize heat rejection of a combustion chamber and piston through perimeter cooling.

Abstract: An engine for a planing-type boat can have a water jacket, which is provided in a main body of the engine and which is supplied with cooling water for cooling the engine. The water jacket can include a ceiling with its rearward portion higher than its forward portion. The water jacket can also include a water drain provided at the rear highest portion of the ceiling to discharge cooling water out of the water jacket. In addition, a head bolt fastening portion for receiving a bolt is provided on an outer side portion of the water jacket in the cylinder head, and a rib is provided in a portion of the water jacket that corresponds to the head bold fastening portion.

Abstract: A compression ignition internal combustion engine having at least one combustion chamber for high ignition pressures. Each combustion chamber comprises a cylinder bore in the crankcase or a cylinder liner in the cylinder bore, a piston, and a cylinder head. Spaces for conveying coolant are disposed in the crankcase such that coolant flows about walls of the cylinder bore or a liner. The cylinder head has coolant chambers. The internal combustion engine has a separate cooled plate disposed between the combustion chamber and the cylinder head. The cooled plate forms a surface cover of the combustion chamber and is connected in a positively engaging and gas tight manner with the crankcase and/or the cylinder liner. Valve seats for at least one inlet valve and at least one outlet valve are disposed in the cooled plate, and at least one injection valve extends through the cooled plate.

Abstract: A cooling block forming a top wall of a combustion chamber of an internal combustion engine is formed by layering, from the outside to the inside, a casing, an upper layer block, a middle layer block, and a lower layer block. Labyrinth-shaped cooling water passages are formed on upper side faces of the three layers of blocks, and cooling water supplied from a cooling water supply passage flows from the cooling water passage on the side far from the combustion chamber to the cooling water passage on the side close to the combustion chamber, and is discharged from a cooling water discharge passage. Since the cooling water flows in a direction opposite to the direction of emission of heat of combustion from the combustion chamber, it is possible to ensure that there is sufficient difference in temperature between a cylinder head and the cooling water throughout the cooling water passages.

Abstract: The present invention provides an engine cooling method and apparatus. The engine cooling apparatus includes a cylinder block having a cylinder head mounted thereto. The cylinder block defines an inlet passage and a block jacket in fluid communication with the inlet passage. The cylinder head defines a lower cylinder head jacket in fluid communication with the block jacket, and an upper cylinder head jacket in fluid communication with the lower cylinder head jacket. The lower cylinder head jacket includes a plurality of nozzles configured to direct engine coolant and thereby provide cooling to portions of the cylinder head located near a plurality of exhaust ports, a plurality of injector ports, and a plurality of intake ports.

Abstract: In a direct injection internal combustion engine, a fuel injection valve and a spark plug of adjacent cylinders are inclined at different angles from each other in directions perpendicular to a cylinder arrangement direction in which the cylinders are arranged. Besides, the fuel injection valve and the spark plug of at least one of the cylinders are inclined at different angles from each other in directions parallel to the cylinder arrangement direction. A cooling channel is provided between the fuel injection valve and the spark plug of the at least one of the cylinders.

Abstract: A cylinder head (10) for an internal combustion engine has hydroformed port liners (18) positioned within selected ports, either exhaust and/or intake ports (14, 16). The hydroformed port liner (18) includes an air gap (24) for an insulation layer within the selected port (14, 16) between an outer surface (19) of the hydroformed port liner (18) and the wall of the port (14, 16). A cylinder head (12) with a predetermined port configuration has selected ports (14, 16) cast with protrusions (22). The selected ports (14,16) have a larger diameter than a standard size port diameter for that cylinder head to provide a predetermined port configuration by a preset amount based on the thickness of the hydroformed port liner (18) and a desired air gap (22). Protrusions (22) in the wall of the selected ports (14, 16) or on the insert sleeves (17) facilitate formation of the air gap during the hydroforming process.

Abstract: A cylinder head (1) for an internal combustion engine, the cylinder head (1) having a top face (1a), a bottom face (1b) arranged to be connected to a cylinder block, a lateral exhaust flange face (1c) arranged to be connected to an exhaust manifold (17), a second lateral face (1d) being opposed to said lateral exhaust flange face (1c), a front face (1e) and an end face (1f).

Abstract: A water-cooled cylinder head is provided for a multicylinder internal-combustion engine having two inlet and outlet valves per cylinder. The cylinder head has a cylinder head cooling space with inflow and outflow openings for the coolant which is integrated in the cylinder head housing and extends above a part-spherical cap forming a combustion chamber volume. Water cooling spaces are formed at least in areas around a receiving opening for a spark plug arranged centrally in the cylinder head housing and around the two outlet valves. The water cooling spaces are mutually connected by way of a common annulus section. At least the common water cooling jacket annulus section has a volume which remains an essentially constant distance from the combustion chamber volume, so that, at least in this area, the wall thickness of the part-spherical combustion chamber cap extends in a uniform manner and to close to the combustion chamber volume.

Abstract: A water-cooled cylinder head for a multicylinder internal-combustion engine, has a cylinder head housing which has charge cycle ducts, passage bores for receiving cylinder head screws, valve stem guides for inlet and outlet valves controlling the charge cycle ducts, and part-spherical combustion chamber caps which are bounded by a water cooling jacket on a side facing away from the combustion chamber. One spark plug dome respectively has an opening leading to the combustion chamber of the respective cylinder. For reinforcing the cylinder head housing and/or for supporting the part-spherical combustion chamber caps, a rib structure is integrated in the cylinder head housing.

Abstract: A cylinder head for a water-cooled, multi-cylinder piston internal combustion engine comprises a lower wall and an upper wall enclosing a cavity. A well extends into the cavity for receiving a fuel injector and/or an ignition device. An intake port and/or an exhaust port extends through the cavity. A cooling-water carrying region comprises areas of the cavity surrounding the well, intake port, and exhaust port. Portions of the cooling-water carrying region are provided with an intermediate web for reinforcing the cylinder head.

Abstract: An improvement to a diesel engine cylinder head disclosed in U.S. Pat. No. 4,860,700, wherein the improvement comprises any of: a by-pass opening formed in partition walls thereof; a spine density of less than about five spines per square inch; spacing an inner chamber wall surface thereof with respect to an inner fire-face wall surface thereof between about 0.75 inches and 0.25 inches; coolant by-pass ports thereof having a cross-section of between about 0.1875 inches and 0.0625 inches; and a radial rib thereof extending complete and free of any rib opening.

Abstract: A cooling water pipe is deformed so as to have outlet openings respectively placed in a position around a fuel injection nozzle and in a position between ports, and the cooling water pipe is inserted to be placed inside the cylinder head. Thereby, the position around the fuel injection nozzle and the position between the ports can be simultaneously and efficiently cooled, and the structure becomes simpler and the production becomes easier. In order to deform the cooling water pipe, for example, the cooling water pipe is bent first, and subsequently bulge forming by hydraulic pressure is performed. Preferably, the cooling water pipe is made of aluminum. Thereby, the cooling water pipe becomes easier to melt into when the cylinder head is cast.

Abstract: An internal combustion engine is provided in which an exhaust port communicating with a combustion chamber formed in a cylinder head is formed from independent exhaust ports, which are positioned on the upstream side, and a grouped exhaust port, in which the plurality of independent exhaust ports are combined. Water supplied from a supply pump passes through a water passage of the grouped exhaust port and a water passage of the independent exhaust ports while cooling the exhaust port, and a valve seat and valve guide on the periphery of the exhaust port, which have high temperatures, thus heating the water itself and thereby recovering waste heat of the internal combustion engine. The heated water carries out heat exchange with exhaust gas in an evaporator provided in an exhaust passage and turns into high temperature, high pressure steam, which drives an expander of a Rankine cycle system.

Abstract: A cylinder head for an internal combustion engine (ICE) includes a lower cooling jacket, an upper cooling jacket and an exhaust manifold disposed therebetween. The exhaust manifold enables exhaust of combustion gas from cylinders of the ICE. The lower cooling jacket has coolant flow paths in fluid communication with coolant flow paths of a cylinder block of the ICE. Coolant flow paths of the upper cooling jacket are in fluid communication with those of the lower cooling jacket through one of a plurality of passages. The passages can be selectively plugged to define coolant flow direction through the cylinder head. The upper and lower cooling jackets are in heat exchange relationship with surfaces of the exhaust manifold to cool exhaust gas flowing therethrough.

Abstract: In a cylinder head structure of a multi-cylinder engine, a head-side water jacket is provided in the cylinder head, a lateral rib extending in the engine width direction is provided at an upper face of the portion located between cylinders of bottom deck, the lateral rib bifurcates, getting around intake-side and exhaust-side connecting holes connecting the head-side water jacket with a water jacket in cylinder block, its both ends are connected with intake-port and exhaust-port walls, and its top portion is configured so as to become taller gradually from its central portion toward its outside portions. Accordingly, rigidity of the portion located between cylinders of the cylinder head can be increased in the cylinder-line direction as well as in the vertical direction, which can improve the sealing between the cylinder block and the cylinder head.

Abstract: A combustion engine includes a cylinder head and a cylinder crankcase having a cylinder bore and a coolant duct formed therein. The coolant duct is disposed adjacent the cylinder bore and is a cooling system component. A cylinder head gasket is provided between the cylinder head and the cylinder crankcase. The coolant duct has a coolant duct upper end and is open toward the cylinder head gasket at the coolant duct upper end. The cylinder head gasket has a side facing the cylinder crankcase when the cylinder head gasket is installed. The cylinder head gasket has a channel formed on the side of the cylinder head gasket that faces the cylinder crankcase. The channel is in a flow connection with the coolant duct and is part of the cooling system.

Abstract: A pair of exhaust ports (4, 4) have flat portions (9, 9) formed on respective inner peripheral surfaces thereof and facing in directions opposite to each other. An intervening cooling water passage (14) is formed between the flat portions (9, 9) when a cylinder head (1) is cast.

Abstract: A cylinder head cooling structure and an oil temperature control system are provided for an internal combustion engine having a plurality of cylinders, each having a plurality of intake ports and a plurality of exhaust ports. The engine includes cooling oil jackets surrounding the spark plugs in the cylinder head, a thermostat attached to the front surface of the crankcase independently of an oil filter, and an oil temperature sensor disposed on a rear face of the cylinder block above the crankcase in an oil supply path formed on the cylinder rear face for supplying oil to the oil jackets. Oil passages conducting oil into the oil jacket are provided between two separate parts of a bifucated intake port and between two separate parts of a bifurcated exhaust port, and only cooling system oil reaching high temperatures is allowed to flow through the thermostat, thereby improving temperature control response.

Abstract: A water-cooled cylinder head is provided for a multicylinder internal-combustion engine having two inlet and outlet valves per cylinder. The cylinder head has a cylinder head cooling space with inflow and outflow openings for the coolant which is integrated in the cylinder head housing and extends above a spherical cap forming a combustion chamber trough. Water cooling spaces are formed at least in areas around a receiving opening for a spark plug arranged centrally in the cylinder head housing and around the two outlet valves. The water cooling spaces are mutually connected by way of a common annulus section. At least the common water cooling jacket annulus section has an essentially constant height toward the combustion chamber trough, so that, at least in this area, the wall thickness of the spherical combustion chamber cap extends in a uniform manner and to close to the combustion chamber trough.

Abstract: A cylinder head structure for an internal combustion engine that is disposed on the upper surface of a cylinder body in which a plurality of cylinders are arranged in the lengthwise direction thereof, and that has an exhaust port, an intake port and a fuel injector mounting hole for each of the cylinders; a boss for bolt hole having a bolt hole for inserting a cylinder head bolt on the exhaust port side and a boss for bolt hole having a bolt hole for inserting a cylinder head bolt on the intake port side being provided between the exhaust ports and between the intake ports of the neighboring cylinders, and a partitioning wall being formed for coupling the boss for bolt hole on the exhaust port side to the boss for bolt hole on the intake port side and for sectionalizing the cooling water chamber, wherein the boss for bolt hole on the intake port side is provided with guide portions that guide the cooling water flowing into the cooling water chamber to the side of the fuel injector mounting hole from the exhau

Abstract: A water-cooled cylinder head for a multicylinder internal-combustion engine, has a cylinder head housing which has charge cycle ducts, passage bores for receiving cylinder head screws, valve stem guides for inlet and outlet valves controlling the charge cycle ducts, and spherical combustion chamber caps which are bounded by a water cooling jacket on a side facing away from the combustion chamber. One spark plug dome respectively has an opening leading to the combustion chamber of the respective cylinder. For reinforcing the cylinder head housing and/or for supporting the spherical combustion chamber caps, a rib structure is integrated in the cylinder head housing.

Abstract: In an internal combustion engine having a coolant circuit which comprises a first coolant line for the cylinder block and a second coolant line for the cylinder head of the engine, with the cylinder head having at least one inlet valve and at least one outlet valve per cylinder, an additional coolant duct provided in the cylinder head in close proximity to the valves is connected to the second coolant line for directly supplying coolant to the area of the cylinder outlet valves.

Abstract: A cylinder head, for an internal combustion engine, enhances engine efficiency while ensuring favorable coolant flow. The cylinder head includes a main casting body 41 having a hollow water jacket formed therein, to allow coolant flow therethrough. The main casting body 41 includes a plurality of cylindrical plug hole walls 91 which have plug holes 90 formed therein inside a head-side water jacket 60. The cylinder head also includes partitions 100, formed inside the head-side water jacket 60, and these partitions connect the plug hole walls 91 together form a dividing wall, which divides the water jacket into an exhaust port section and an intake port section. Coolant entering the water jacket is divided into two substreams, which flow initially in substantially opposite directions, and which are reunited after flowing around opposite ends of the dividing wall.

Abstract: The invention relates to a cylinder head comprising a water jacket that is delimited by a flame deck and an oil deck in a water-cooled reciprocating engine with cylinders that are arranged in series, each of said cylinders having at least one intake valve comprising intake ducts and two exhaust valves, whose exhausts open into exhaust ducts, in addition to a receptacle for a fuel injector or a spark plug that is located between the intake valve and the exhaust valves. The cylinder head is characterised in that a system of channels is provided at least in the vicinity of the exhaust side of each cylinder in order to conduct the coolant in the water jacket, whereby the coolant supply is conducted through said system from the exterior on one side of the exhaust duct towards the receptacle and is returned from the interior to the exterior on the other side of the exhaust duct and in that an overflow channel is provided.

Abstract: The bottom surface 18 of the cylinder head 10 is formed by an intake-side bottom surface 18a and an exhaust-side bottom surface 18b on which an intake port 13 and an exhaust port 15 are formed respectively. Further, a first wall 19 formed between an intake-side water jacket 16 and the intake-side bottom surface 18a is larger in thickness than a second wall 20 formed between an exhaust-side water jacket 17 and the exhaust-side bottom surface 18b. This structure can reduce an amount of HC included in exhaust gas.

Abstract: A cylinder head for a water-cooled, multi-cylinder piston internal combustion engine comprises a lower wall and an upper wall enclosing a cavity. A well extends into the cavity for receiving a fuel injector and/or an ignition device. An intake port and/or an exhaust port extends through the cavity. A cooling-water carrying region comprises areas of the cavity surrounding the well, intake port, and exhaust port. Portions of the cooling-water carrying region are provided with an intermediate web for reinforcing the cylinder head.

Abstract: A cooling structure for uniformly cooling a bore wall of a cylinder block using a cooling medium, the bore wall surrounding plural bore regions, includes a water jacket portion which is provided so as to surround an entire outer periphery of the bore wall, and which is supplied with the cooling medium; a water jacket spacer which is inserted in the water jacket portion; a passage through which the cooling medium in a portion of an inter-bore region is transferred to another portion of the inter-bore region, the inter-bore region being positioned in a vicinity of a boundary between the bore regions adjacent to each other; and a flow promotion device which increases a flow rate of the cooling medium flowing in the passage.

Abstract: In a cylinder head structure of a multi-cylinder engine, a head-side water jacket is provided in the cylinder head, a lateral rib extending in the engine width direction is provided at an upper face of the portion located between cylinders of bottom deck, the lateral rib bifurcates, getting around intake-side and exhaust-side connecting holes connecting the head-side water jacket with a water jacket in cylinder block, its both ends are connected with intake-port and exhaust-port walls, and its top portion is configured so as to become taller gradually from its central portion toward its outside portions. Accordingly, rigidity of the portion located between cylinders of the cylinder head can be increased in the cylinder-line direction as well as in the vertical direction, which can improve the sealing between the cylinder block and the cylinder head.

Abstract: A cooling structure of a cylinder block includes a water jacket portion which is provided so as to surround an entire outer periphery of the bore wall; a water jacket spacer which is inserted in the water jacket portion; and a gasket which is provided in an upper portion of the cylinder block, and which includes a hole leading to the water jacket portion. The water jacket portion is supplied with coolant. A distance between a center of the hole and an outer periphery of the cylinder block is shorter than a distance between a center of the water jacket spacer in a thickness direction and the outer periphery of the cylinder block. In the cooling structure, the cylinder block can be uniformly cooled.

Abstract: An improvement to a diesel engine cylinder head disclosed in U.S. Pat. No. 4,860,700, wherein the improvement comprises any of: a by-pass opening formed in partition walls thereof; a spine density of less than about five spines per square inch; spacing an inner chamber wall surface thereof with respect to an inner fire-face wall surface thereof between about 0.75 inches and 0.25 inches; coolant by-pass ports thereof having a cross-section of between about 0.1875 inches and 0.0625 inches; and a radial rib thereof extending complete and free of any rib opening.

Abstract: A cylinder head for a liquid-cooled multi-cylinder internal combustion engine, with a cooling chamber configuration adjacent to a fire deck, which is partitioned by an intermediary deck essentially parallel to the fire deck into a lower cooling chamber in the direction of the cylinder axis, where lower and upper cooling chambers are flow-connected by at least one main transfer opening for each cylinder in the area of the side wall of the cylinder head and by at least one auxiliary transfer opening in the region of a preferably central opening for the insertion of a fuel injection device. At least one auxiliary transfer opening is configured as a recess in the insertion opening, and at least one first auxiliary transfer opening is located in at least one of the areas between intake passage and insertion opening and/or exhaust passage and insertion opening.

Abstract: In a cylinder head for a multi-cylinder internal combustion engine including a cylinder head roof with a coolant space disposed below and an oil space disposed above the cylinder head roof, a number of cylinder head bolt support columns arranged along the side walls of the cylinder head, and a recess formed in each cylinder head section for receiving a spark plug or a fuel injection nozzle, laterally extending reinforcement ribs are provided in the oil space which extend in each cylinder head section between the cylinder head structure surrounding the recess and the cylinder head bolt support columns so as to provide a reinforcement grid for the cylinder head.

Abstract: A cooling water pipe is deformed so as to have outlet openings respectively placed in a position around a fuel injection nozzle and in a position between ports, and the cooling water pipe is inserted to be placed inside the cylinder head. Thereby, the position around the fuel injection nozzle and the position between the ports can be simultaneously and efficiently cooled, and the structure becomes simpler and the production becomes easier. In order to deform the cooling water pipe, for example, the cooling water pipe is bent first, and subsequently bulge forming by hydraulic pressure is performed. Preferably, the cooling water pipe is made of aluminum. Thereby, the cooling water pipe becomes easier to melt into when the cylinder head is cast.

Abstract: A cylinder head for an internal combustion engine (ICE) includes a lower cooling jacket, an upper cooling jacket and an exhaust manifold disposed therebetween. The exhaust manifold enables exhaust of combustion gas from cylinders of the ICE. The lower cooling jacket has coolant flow paths in fluid communication with coolant flow paths of a cylinder block of the ICE. Coolant flow paths of the upper cooling jacket are in fluid communication with those of the lower cooling jacket through one of a plurality of passages. The passages can be selectively plugged to define coolant flow direction through the cylinder head. The upper and lower cooling jackets are in heat exchange relationship with surfaces of the exhaust manifold to cool exhaust gas flowing therethrough.

Abstract: A cylinder head for a water-cooled multi-cylinder internal-combustion engine has two intake valves and outlet valves per cylinder. A cylinder head cooling chamber has inflow and outflow openings for coolant as well as a receiving opening for a spark plug. The receiving opening is arranged centrally relative to the cylinder head cooling chamber of a cylinder. On the inflow side in the cylinder head cooling chamber, a main cooling flow runs between the two outlet valves in the direction of the receiving opening for the spark plug, while two secondary cooling flows are provided at the two edge areas of the inflow side.

Abstract: An internal combustion engine is provided in which an exhaust port (16) communicating with a combustion chamber (24) formed in a cylinder head (20) is formed from independent exhaust ports (16A), which are positioned on the upstream side, and a grouped exhaust port (16B), in which the plurality of independent exhaust ports (16A) are combined. Water supplied from a supply pump passes through a water passage (W1) of the grouped exhaust port (16B) and a water passage (W2) of the independent exhaust ports (16A) while cooling the exhaust port (16), and a valve seat (29) and valve guide (40) on the periphery of the exhaust port (16), which have high temperatures, thus heating the water itself and thereby recovering waste heat of the internal combustion engine. The heated water carries out heat exchange with exhaust gas in an evaporator provided in an exhaust passage and turns into high temperature, high pressure steam, which drives an expander of a Rankine cycle system.

Abstract: A cooling block (51) forming a top wall of a combustion chamber (19) of an internal combustion engine is formed by layering, from the outside to the inside, a casing (52), an upper layer block (53), a middle layer block (54), and a lower layer block (55). Labyrinth-shaped cooling water passages (53a, 54a, 55a) are formed on upper faces and side faces of the three layers of blocks (53, 54, 55), and cooling water supplied from a cooling water supply passage (56) flows from the cooling water passage (53a) on the side far from the combustion chamber (19) to the cooling water passage (55a) on the side close to the combustion chamber (19), and is discharged from a cooling water discharge passage (57).

Abstract: Head cooling passages are formed around intake ports and exhaust ports provided in a cylinder head, and a flow control member which controls the volume of cooling medium flowing toward the intake ports to be larger than the volume of cooling medium flowing toward the exhaust ports is provided in the vicinity of a supply port via which cooing medium is supplied.

Abstract: The water jacket includes at least two exhaust ports configured to exhaust combusted gases from a cylinder. The water jacket also defines a lower path, an higher path, and a central path. The higher path is configured for circulating cooling fluid above the at least two exhaust ports. The lower path is configured for circulating cooling fluid below the at least two exhaust ports. Also, the central path fluidly couples the lower path to the higher path. The central path also separates the at least two exhaust ports from one another. The central path is also configured for circulating cooling fluid between said at least two exhaust ports. A restricted portion is formed in the lower path on one side of said central path. The restricted portion is configured to restrict flow through the restricted portion of the lower path, thereby forcing cooling fluid through the central path.

Abstract: A cooling chamber for a cylinder head including a floor portion, a ceiling portion, and sidewall portions extending between the floor portion and ceiling portion. The cooling chamber may also include at least one exhaust port conduit extending through the cooling chamber from the floor portion towards the ceiling portion, at least one intake port conduit extending through the cooling chamber from the floor portion towards the ceiling portion, and a well portion. The at least one intake port conduit and the at least one exhaust port conduit may be disposed around the well portion. The cooling chamber may include a plurality of rib formations extending inwardly from the sidewall portions and a plurality of inlets arranged around a periphery of the cooling chamber. The rib formations are configured to deflect the coolant flow around the conduits towards the well portion.

Abstract: A cylinder head, for an internal combustion engine, enhances engine efficiency while ensuring favorable coolant flow. The cylinder head includes a main casting body 41 having a hollow water jacket formed therein, to allow coolant flow therethrough. The main casting body 41 includes a plurality of cylindrical plug hole walls 91 which have plug holes 90 formed therein inside a head-side water jacket 60. The cylinder head also includes partitions 100, formed inside the head-side water jacket 60, and these partitions connect the plug hole walls 91 together form a dividing wall, which divides the water jacket into an exhaust port section and an intake port section. Coolant entering the water jacket is divided into two substreams, which flow initially in substantially opposite directions, and which are reunited after flowing around opposite ends of the dividing wall.

Abstract: A cylinder head structure for an internal combustion engine that is disposed on the upper surface of a cylinder body in which a plurality of cylinders are arranged in the lengthwise direction thereof, and that has an exhaust port, an intake port and a fuel injector mounting hole for each of the cylinders; a boss for bolt hole having a bolt hole for inserting a cylinder head bolt on the exhaust port side and a boss for bolt hole having a bolt hole for inserting a cylinder head bolt on the intake port side being provided between the exhaust ports and between the intake ports of the neighboring cylinders, and a partitioning wall being formed for coupling the boss for bolt hole on the exhaust port side to the boss for bolt hole on the intake port side and for sectionalizing the cooling water chamber, wherein the boss for bolt hole on the intake port side is provided with guide portions that guide the cooling water flowing into the cooling water chamber to the side of the fuel injector mounting hole from the exhau

Abstract: In a multi cylinder internal combustion engine comprising a cylinder head internally defining exhaust passages and a converging area into which the exhaust passages converge, an upper water jacket and a lower water jacket are formed above and below the exhaust passages, and the lower water jacket has a greater volume than the upper water jacket. Thus, the cooling efficiency for the converging area can be improved by increasing the volume of the part of the water jacket adjacent to the converging area. Also, because the upper water jacket has a relatively small volume, the load on the core parts supporting the core part for defining the upper water jacket can be reduced, and the overall mechanical strength of the core can be improved. By extending the water jackets to the converging area, the cooling efficiency can be improved even further.