A piston for an internal combustion engine may include a piston head and a piston skirt. The piston head may include a piston crown, a circumferential fire land, a circumferential ring belt having a plurality of ring grooves, and a circumferential cooling duct. The cooling duct may be open in a direction away from the fire land and may be at least partially closed by a closure element. The cooling duct may include a cooling duct bottom and a cooling duct ceiling. The piston skirt may have at least two piston bosses connected to one another via at least two running faces. At least one running face may have an inner face connected via a connecting land to an underside of the piston head.

A piston for an internal combustion engine may include a piston head and a piston skirt. The piston head may include a piston crown, a circumferential fire land, a circumferential ring belt having a plurality of ring grooves, and a circumferential cooling duct. The cooling duct may be open in a direction away from the fire land and may be at least partially closed by a closure element. The cooling duct may include a cooling duct bottom and a cooling duct ceiling. The piston skirt may have at least two piston bosses connected to one another via at least two running faces. At least one running face may have an inner face connected via a connecting land to an underside of the piston head.

A piston and methods for constructing a piston for use in an internal combustion engine are presented wherein the piston includes a cylindrical body extending from the crown. The cylindrical body defines a ring groove, and a portion of the cylindrical body defines a non-circular cross-section below the ring groove. The ring groove is configured to correspond with an associated sealing ring. The non-circular cross-section creates a gap between the cylindrical body and an associated cylinder wall enabling a quantity of oil to pass from an annular region between the cylindrical body and the associated cylinder wall.

A piston and methods for constructing a piston for use in an internal combustion engine are presented wherein the piston includes a cylindrical body extending from the crown. The cylindrical body defines a ring groove, and a portion of the cylindrical body defines a non-circular cross-section below the ring groove. The ring groove is configured to correspond with an associated sealing ring. The non-circular cross-section creates a gap between the cylindrical body and an associated cylinder wall enabling a quantity of oil to pass from an annular region between the cylindrical body and the associated cylinder wall.

In an engine piston assembly of the present invention, a piston structure, together with a piston ring set matched to the piston structure and an inner wall of a cylinder bore body, forms a crevice passage having at least two annular expansion chambers and also having a function of multistage throttling and expansion. The engine piston assembly of the present invention can not only greatly and effectively reduce the intra-cylinder carbon deposition and the hydrocarbon emissions in the exhaust gas emissions of the engine, but also significantly improve the engine efficiency and the overall performance of the engine, so that the present invention is suitable for wide applications.

In an engine piston assembly of the present invention, a piston structure, together with a piston ring set matched to the piston structure and an inner wall of a cylinder bore body, forms a crevice passage having at least two annular expansion chambers and also having a function of multistage throttling and expansion. The engine piston assembly of the present invention can not only greatly and effectively reduce the intra-cylinder carbon deposition and the hydrocarbon emissions in the exhaust gas emissions of the engine, but also significantly improve the engine efficiency and the overall performance of the engine, so that the present invention is suitable for wide applications.

A cooling channel cover for a piston of an internal combustion engine may include a body having mutually opposite end faces. At least one supply element for a coolant may be received in an opening disposed in the cooling channel cover. The supply element may include an inlet region and an outlet region, and may be held on the cooling channel cover via a clipped-in latching connection. A spring tab may be disposed on the inlet region of the supply element, and/or a latching element may be disposed on the outlet region of the supply element. The spring clip may engage one of the end faces and the latching element may engage the opposite end face.

A cooling channel cover for a piston of an internal combustion engine may include a body having mutually opposite end faces. At least one supply element for a coolant may be received in an opening disposed in the cooling channel cover. The supply element may include an inlet region and an outlet region, and may be held on the cooling channel cover via a clipped-in latching connection. A spring tab may be disposed on the inlet region of the supply element, and/or a latching element may be disposed on the outlet region of the supply element. The spring clip may engage one of the end faces and the latching element may engage the opposite end face.

A method for producing a cooling channel piston may include producing a salt core blank by pressing and sintering a pure salt material having a surface roughness R.sub.z of at most 60 μm. The method may also include one of immersing the salt core blank into a saturated solution of the salt material, or spraying the salt core blank with a saturated solution of the salt material. The method may also include drying the salt core blank to form a salt core having a surface roughness R.sub.z of at least 200 μm. The method may further include placing the salt core in a casting mold, and casting the cooling channel piston from a metallic casting material.

A piston construction with an end surface is equipped with a pattern of insulating cavities embedded in an upper end of the piston, between the end surface and interior portions of the piston that are cooled by circulating liquid coolant.