An engine system includes an engine housing having a cylinder block and a cylinder head. An intake opening and an exhaust opening and an igniter opening are formed in a fire deck surface of the cylinder head. A plurality of always-open fuel admission ports are fluidly connected to a combustion chamber and arranged in at least one of the cylinder block or the cylinder head. The always-open fuel admission ports convey a gaseous fuel such as a gaseous hydrogen fuel, a gaseous hydrocarbon fuel, or still others, to the combustion chamber.

A combustion chamber structure in which an installation hole of the injector is improved to realize a rapid combustion and to reduce an unburned hydrocarbon. In the combustion chamber, a leading end of an injector is withdrawn from an upper end of an opening of an installation hole, and an additionally expanded surface area is formed on an upper inner surface of the installation hole from a portion to which the leading end of the injector is situated to an opening end of the installation hole. An angle between the additionally expanded surface area and a joint surface of a cylinder head is narrower than an angle between a center axis of the installation hole and the joint surface.

A cylinder head for an internal combustion engine, wherein the cylinder head (1) comprises at least one first component part (12) and at least one second component part (13) joined to the at least one first component part (12), wherein the at least one first component part (12) is manufactured with the use of at least one of the group consisting of primary shaping, forming and cutting, wherein the at least one second component part (13) is manufactured with the use of an additive manufacturing method.

A cylinder having at least one intake port and at least one exhaust port, wherein the at least one intake port includes an upper surface and a lower surface, the upper surface of the intake port having an entrance portion and an outlet portion, the upper surface arced from the entrance portion to the outlet portion.

Various embodiments of the present disclosure are directed to liquid-cooled cylinder heads. In one example embodiment, a cylinder head is disclosed including a component which extends into a combustion chamber, an upper cooling jacked, a lower cooling jacket, a plurality of valves arranged around the component, a plurality of cylinder head screws, an oil deck, a fire deck, a plurality of valve guides, and a fixed connection. The fixed connection is arranged from each valve guide to the component, and is a ring having at least one support. The support and the ring extend at least from the oil deck to the fire deck thereby hounding the combustion chamber, and the component is connected to the plurality of cylinder head screws.

An annular cylinder liner includes an annular body defining a longitudinal axis, a radial direction perpendicular to the longitudinal axis, a circumferential direction, a first longitudinal end, a second longitudinal end, and a liner length measured from the first longitudinal end to the second longitudinal end along the longitudinal axis. The annular body also includes a shoulder that is disposed at the first longitudinal end, defining a shoulder axial thickness measured along the longitudinal axis. A ratio of the liner length to the shoulder axial thickness ranges from 24.0 to 46.0.

An internal combustion engine includes a hollow cylinder, a piston within the hollow cylinder, and a cylinder head. A base valve assembly at a base of the hollow cylinder permits or restricts fluid flow from an intake manifold into a sub-chamber below the piston. The piston includes at least one intake port connecting a combustion chamber above the piston with the sub-chamber, and a transfer valve that opens and closes the at least one intake port. When the transfer valve opens the at least one intake port, fluid is permitted to flow from the sub-chamber to the combustion chamber. The internal combustion engine operates according to a four-stroke piston cycle, wherein multiple intake stages are provided. The intake stages may include intake of air into the sub-chamber during a compression stroke, transfer of air from the sub-chamber to the combustion chamber during a power stroke, intake of air-fuel mixture into the sub-chamber during an exhaust stroke, and transfer of air-fuel mixture from the sub-chamber to the combustion chamber during an intake stroke.

An internal combustion engine has a cylinder head having a cylinder roof defining first and second intake ports. The cylinder head supports a spark plug positioned between a central axis of the cylinder roof and a fuel injector. A combustion pre-chamber is connected to and extends outwardly from the roof. The pre-chamber encapsulates the spark plug, and is offset from the central axis and positioned between the central axis and the first and second intake ports. The pre-chamber defines an inlet aperture and an outlet aperture positioned along a spray streamline of the fuel injector, and defines first and second side apertures. Each side aperture is positioned adjacent to a respective one of the first and second intake ports. A method of operating an engine having a pre-chamber is also provided.

An internal combustion engine has a cylinder head having a cylinder roof defining first and second intake ports. The cylinder head supports a spark plug positioned between a central axis of the cylinder roof and a fuel injector. A combustion pre-chamber is connected to and extends outwardly from the roof. The pre-chamber encapsulates the spark plug, and is offset from the central axis and positioned between the central axis and the first and second intake ports. The pre-chamber defines an inlet aperture and an outlet aperture positioned along a spray streamline of the fuel injector, and defines first and second side apertures. Each side aperture is positioned adjacent to a respective one of the first and second intake ports. A method of operating an engine having a pre-chamber is also provided.

A structure of a combustion chamber for an engine includes a crown surface of a piston, a cylinder wall surface, a combustion chamber ceiling surface, and an ignition plug which includes an ignition portion. The crown surface of the piston includes: a cavity recessed in the cylinder axis direction; a parallel surface portion which is in parallel to a corresponding region on the combustion chamber ceiling surface at a position above the cylinder axis direction with a gap, when the piston is at a compression top dead center; and an inclined surface portion formed to continue to the parallel surface portion in such a way as to be directed to the ignition plug, when the piston is at a compression top dead center. The parallel surface portion and the corresponding region, in combination, constitute a squish flow generation portion generating a squish flow when the piston is lifted.