An improved air-cooled aviation engine includes a compact combustion chamber having an intake valve opening, an exhaust valve opening, and a generally elliptical shape. The elliptical shape has a major axis and a minor axis, with the major axis intersecting both the intake valve opening and the exhaust valve opening. In some examples, the major axis is the same length or shorter than a diameter of a cylinder bore of the engine, and the minor axis is smaller than the major axis. Combustion is thus constrained to a smaller area than that of the cylinder bore.

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 of an engine in which a thermal stress acting between a valve seat made of clad material and a base metal is reduced. The cylinder head comprises: an inner wall surface; a pair of intake ports arranged adjacent to each other; a valve seat formed of clad material around each intake port; a mask section formed within a predetermined range of a circumference of each intake port to protrude toward a combustion chamber; and a cavity formed between a pair of the mask sections by partially depressing the inner wall surface toward the combustion chamber.

An injector seal assembly including a nozzle combustion shield is disclosed, the thermally conductive component of the injector seal assembly defining at least one groove to allow fluid communication between the main combustion chamber and a gap defined by a fuel injector and the injector seal assembly to facilitate the prevention of corrosion of the components.

To provide an engine head structure for “omission or shortening a fuel pipe that withstands a high pressure”, “simplification or omission of a support bracket for a fuel accumulator and/or a fuel injection device”, “reduction of the number of parts” by devising a fuel accumulator and a support structure therefor, and the like. An engine head structure has a support bracket for mounting a fuel accumulator including a joining portion with a fuel injection device on a cylinder head, is disposed on a side of the fuel injection device or between adjacent fuel injection devices. The support bracket includes a member having a mounting portion on which the fuel accumulator is placed and mounted, a mounting leg portion extending from the mounting portion and mounted on the cylinder head, and an aligning leg portion extending from the mounting portion for positioning the support bracket with respect to the cylinder head.

There is provided a water cooled engine including a cylinder head with minimized thermal strain. A head water jacket includes an inter-exhaust-port-wall water channel between a first exhaust entrance port wall and a second exhaust entrance port wall. A cylinder head includes a cooling water injection passage provided at a bottom wall of the cylinder head. The cooling water injection passage is positioned on the exhaust end side, and includes a passage entrance provided on the exhaust end side, and a passage exit directed toward the inter-exhaust-port-wall water channel. An exhaust port wall includes a heat dissipation fin extending from a first exhaust entrance port wall toward an exhaust end. The space between the heat dissipation fin and a second exhaust entrance port wall forms a water channel entrance of the inter-exhaust-port-wall water channel.

Methods and systems are provided for a cylinder head. In one example, a system comprises cylinder head having a bore arranged therein. The bore comprises a coupling element therein configured to selectively receive an ignition plug.

A cylinder head for an internal combustion engine with at least one cylinder has a cooling duct system which has a coolant inlet side and a coolant outlet side, a combustion chamber section, two coolant-inlet-side gas ducts, two coolant-outlet-side gas ducts and two adjacent component openings, such as a spark plug opening and an injection nozzle opening. The cylinder head has an annular wall section provided between the component openings, on the one hand, and the gas ducts, on the other hand. The cooling duct system has a web cooling duct which runs into the annular wall section, extends between the coolant-inlet-side gas ducts and has an upper wall. The upper wall has a guiding surface which is directed obliquely downwards in the region of the annular wall section in order to deflect coolant in the direction of the combustion chamber section.

A cylinder head in a cylinder head assembly includes an upper deck, a fire deck, gas exchange conduits, and a coolant cavity extending peripherally around the gas exchange conduits. The cylinder head also includes an igniter socket having an igniter post, and a radially outward sleeve step continuously circumferential of an igniter bore center axis. A cooling moat is formed between the igniter post and the sleeve step. The coolant cavity includes a valve bridge through-channel and a valve bridge part-way channel each fluidly connected to the igniter socket to provide coolant flow into and out of the cooling moat passively.

An engine power module includes a water jacket, a cylinder liner, and a cylinder head. The water jacket forms a coolant supply conduit arranged in a lower coolant annulus extending around the cylinder liner and an upper coolant annulus extending around the cylinder head. The cylinder head has formed therein an injector bore, and a plurality of drill holes convergent on the injector bore. A lower coolant cavity in the cylinder head forms a coolant flow path extending circumferentially around the injector bore between a cavity inlet opening fluidly connected to the coolant supply conduit, and a cavity connection opening fluidly connected to an upper coolant cavity. The arrangement provides flows of coolant through the drill holes to cool an injector sleeve, and separate coolant flows through the lower coolant cavity and upper coolant cavity.