The present invention suppresses leakage of combustion gas from a contact surface. A cylinder head (20) is attached to a cylinder block. The surface (26) of the side of the cylinder head (20) that is attached to the cylinder block includes a first region (AH1) and a second region (AH2) that has higher hardness than the first region (AH1).

The present invention suppresses leakage of combustion gas from a contact surface. A cylinder head (20) is attached to a cylinder block. The surface (26) of the side of the cylinder head (20) that is attached to the cylinder block includes a first region (AH1) and a second region (AH2) that has higher hardness than the first region (AH1).

An internal combustion engine cylinder head has a water jacket, a plurality of female threaded portions for attaching an exhaust component, and a plurality of bulging portions protruding into the water jacket. The water jacket has inlet portions for receiving cooling water and outlet portions for discharging the cooling water. The inlet portions are disposed in a central position of the water jacket in a cylinder row direction. The outlet portions are disposed on a lateral side of the cylinder head to which the exhaust component is attached. A spacing between the outlet portions is wider than a spacing between the inlet portions. The female threaded portions protrude into the water jacket so that the cooling water crosses an area around the female threaded portions in the cylinder row direction. The bulging portions extend from ends of the female threaded portions towards where the inlet portions are located.

An internal combustion engine cylinder head has a water jacket, a plurality of female threaded portions for attaching an exhaust component, and a plurality of bulging portions protruding into the water jacket. The water jacket has inlet portions for receiving cooling water and outlet portions for discharging the cooling water. The inlet portions are disposed in a central position of the water jacket in a cylinder row direction. The outlet portions are disposed on a lateral side of the cylinder head to which the exhaust component is attached. A spacing between the outlet portions is wider than a spacing between the inlet portions. The female threaded portions protrude into the water jacket so that the cooling water crosses an area around the female threaded portions in the cylinder row direction. The bulging portions extend from ends of the female threaded portions towards where the inlet portions are located.

A cylinder head assembly includes a cylinder head casting, and an injector sleeve within an injector bore in the cylinder head casting. The injector sleeve includes a first sleeve end, and an injector clamping surface formed by an inner sleeve surface adjacent to a cylindrical second sleeve end. The injector sleeve further includes a sleeve clamping surface in contact with an upward facing middle deck surface of the cylinder head casting, and a reaction wall extending between the injector clamping surface and the sleeve clamping surface to transfer an injector clamping load to the upward facing middle deck surface.

A cylinder head assembly includes a cylinder head casting, and an injector sleeve within an injector bore in the cylinder head casting. The injector sleeve includes a first sleeve end, and an injector clamping surface formed by an inner sleeve surface adjacent to a cylindrical second sleeve end. The injector sleeve further includes a sleeve clamping surface in contact with an upward facing middle deck surface of the cylinder head casting, and a reaction wall extending between the injector clamping surface and the sleeve clamping surface to transfer an injector clamping load to the upward facing middle deck surface.

Various embodiments of the present disclosure are directed to an internal combustion engine cylinder head. In one example embodiment, the cylinder head includes a combustion chamber, a fire deck, an intermediate deck remote from a combustion chamber, a central receptacle that receives an injection or ignition device, at least one valve bridge, at least two adjacent gas exchange valves, a top-down cooling system, at least one first transfer opening, and at least one second transfer opening. The top-down cooling system including a first sub-cooling chamber and a second sub-cooling chamber. The at least one first transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber. The at least one second transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber is arranged in the region in the region of the at least one valve bridge between the at least two adjacent gas exchange valves.

Various embodiments of the present disclosure are directed to an internal combustion engine cylinder head. In one example embodiment, the cylinder head includes a combustion chamber, a fire deck, an intermediate deck remote from a combustion chamber, a central receptacle that receives an injection or ignition device, at least one valve bridge, at least two adjacent gas exchange valves, a top-down cooling system, at least one first transfer opening, and at least one second transfer opening. The top-down cooling system including a first sub-cooling chamber and a second sub-cooling chamber. The at least one first transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber. The at least one second transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber is arranged in the region in the region of the at least one valve bridge between the at least two adjacent gas exchange valves.

Combustion engines, and more particularly, integrating a supercritical fluid passageway into a cylinder head and/or cylinder block of an engine, and preferably, a combustion engine. Both a combustion engine system and a method of cooling a cylinder head in an internal combustion engine, utilizing supercritical fluid, are disclosed.

A cylinder head is disclosed herein to allow for temperature control of exhaust gases exiting from an associated exhaust manifold. The cylinder head includes a combustion section that defines a plurality of combustion chambers and an exhaust manifold coupled to the combustion section. The combustion section fluidly couples to exhaust inlets defined by the exhaust manifold. The exhaust manifold includes at least one exhaust passageway in fluid communication with the exhaust inlets and in fluid communication with an exhaust outlet to receive combustion gases from the combustion section and output the same via the exhaust outlet. The exhaust manifold further includes at least one coolant passageway that at least partially surrounds the at least one exhaust passageway to pass coolant therethrough in order to draw and reject heat from exhaust gases.