A cooling structure of an internal combustion engine includes a thermostat provided to switch circulation between a radiator passage and a bypass passage in an engine body, to thereby enable acceleration of early warming up via the bypass passage without impairing the external appearance or increasing the size of the internal combustion engine. The cooling structure also includes an in-cylinder-block fluid passage partitioned up and down in an axial direction of a cylinder axis into an in-cylinder-block upper fluid passage and an in-cylinder-block lower fluid passage by a partition wall. The bypass passage is partially composed of the in-cylinder-bock lower fluid passage.

A cylinder head for use with an internal combustion engine, the cylinder head including a body having a fire deck and defining a water jacket in fluid communication with a cooling system, a first runner defined by the body and open to the fire deck to at least partially form a first valve seat, a second runner defined by the body and open to the fire deck to at least partially form a second valve seat, and a channel defined by the in fluid communication with the water jacket and positioned between the first runner and the second runner. The channel, in turn, includes a first inlet through which a first flow enters the channel, a second inlet through which a second flow enters the channel, and where the first inlet and the second inlet are oriented such that the first flow and the second flow interact with one another to create a turbulent region within the channel.

A cylinder head includes: an exhaust port configured to lead out exhaust gas from combustion chamber; an intake port configured to introduce fresh air into the combustion chamber; an intake air aggregate part configured to aggregate the intake port; and a second EGR pipe in which EGR gas flows, wherein exhaust outlets of the exhaust port and an EGR gas inlet of the second EGR pipe are arranged side-by-side on a flat left side surface, and a fresh air inlet of the intake air aggregate part and an EGR gas outlet of the second EGR pipe are arranged side-by-side on a flat right side surface.

A system includes an engine head that mounts to an engine block of a reciprocating engine, and the engine head includes an intake flow path, an exhaust flow path, a coolant flow path, and first and second sealing registers disposed on opposite sides of the coolant flow path. In addition, the first and second sealing registers are configured to receive a valve guide that supports a valve stem of an exhaust valve. Moreover, the first sealing register is disposed in a wall separating the exhaust flow path and the coolant flow path. Also, a first wall portion of the wall extends between the first sealing register and an exhaust valve seat configured to receive a valve head of the exhaust valve, and a second wall portion of the wall extends from the first sealing register away from the first wall portion.

A system includes an engine head that mounts to an engine block of a reciprocating engine, and the engine head includes an intake flow path, an exhaust flow path, a coolant flow path, and first and second sealing registers disposed on opposite sides of the coolant flow path. In addition, the first and second sealing registers are configured to receive a valve guide that supports a valve stem of an exhaust valve. Moreover, the first sealing register is disposed in a wall separating the exhaust flow path and the coolant flow path. Also, a first wall portion of the wall extends between the first sealing register and an exhaust valve seat configured to receive a valve head of the exhaust valve, and a second wall portion of the wall extends from the first sealing register away from the first wall portion.

A cylinder head of an internal combustion engine, comprising at least one cylinder, a cooling jacket arrangement with a first cooling jacket arranged in the region of a longitudinal central plane of the cylinder head, a second cooling jacket facing a fire deck of the cylinder head, and a third cooling jacket facing away from the fire deck, wherein the first cooling jacket and the second cooling jacket are flow connected to the third cooling jacket via at least one first transfer section and at least one second transfer section respectively.

A cylinder head of an internal combustion engine, comprising at least one cylinder, a cooling jacket arrangement with a first cooling jacket arranged in the region of a longitudinal central plane of the cylinder head, a second cooling jacket facing a fire deck of the cylinder head, and a third cooling jacket facing away from the fire deck, wherein the first cooling jacket and the second cooling jacket are flow connected to the third cooling jacket via at least one first transfer section and at least one second transfer section respectively.

A cooling system for a cylinder head of an internal combustion engine includes a cylindrical seat configured to engage an exhaust valve, a first coolant jacket, and a first conduit. The exhaust valve seat defines an annular cooling passage extending along a circumference of the cylindrical seat. A wall of the cylindrical seat defines a first opening into the annular cooling passage and a second opening into the annular cooling passage, where the first opening is positioned diametrically opposite to the second opening. The first coolant jacket is positioned adjacent to a fire-deck of the internal combustion engine. The first conduit fluidly couples the first coolant jacket to the at least one of the first opening and the second opening to the annular cooling passage in the exhaust valve seat.

A cooling system for a cylinder head of an internal combustion engine includes a cylindrical seat configured to engage an exhaust valve, a first coolant jacket, and a first conduit. The exhaust valve seat defines an annular cooling passage extending along a circumference of the cylindrical seat. A wall of the cylindrical seat defines a first opening into the annular cooling passage and a second opening into the annular cooling passage, where the first opening is positioned diametrically opposite to the second opening. The first coolant jacket is positioned adjacent to a fire-deck of the internal combustion engine. The first conduit fluidly couples the first coolant jacket to the at least one of the first opening and the second opening to the annular cooling passage in the exhaust valve seat.

An engine device including a cylinder head provided with a plurality of air-intake passages for taking fresh air into a plurality of air-intake ports and a plurality of exhaust gas passages for emitting exhaust gas from a plurality of exhaust gas ports. An air-intake manifold which aggregates the air-intake passages is formed integrally with one of left and right side portions of the cylinder head. An EGR cooler is coupled to a front surface of the cylinder head; and EGR gas passages and cooling water passages communicating with the EGR cooler are provided in a coupling portion of the cylinder head with the EGR cooler.