A piston, in particular, a gallery-cooled piston for an internal combustion engine has a piston bottom part and a piston upper part which are connected in a joining process to produce the piston. The piston upper part has at least one ring zone and an inner wall. The piston bottom part has a radially circumferential oblique surface at the end which faces the piston upper part. The oblique surface, interacting with the inner wall of the piston upper part, brings about a centering action during the joining process of the piston parts. A joining method for manufacturing a piston is also disclosed.

A piston, in particular, a gallery-cooled piston for an internal combustion engine has a piston bottom part and a piston upper part which are connected in a joining process to produce the piston. The piston upper part has at least one ring zone and an inner wall. The piston bottom part has a radially circumferential oblique surface at the end which faces the piston upper part. The oblique surface, interacting with the inner wall of the piston upper part, brings about a centering action during the joining process of the piston parts. A joining method for manufacturing a piston is also disclosed.

A piston capable of operating at a high temperature and consequently contributing to a high in-cylinder temperature, as well as reducing engine oil temperature, when used in an internal combustion engine, is provided. The piston includes an upper portion and a lower portion welded together to present a cooling gallery therebetween. The cooling gallery extends circumferentially around a center axis of the piston and is spaced the center axis. A partition is located in the cooing gallery and extends from one inner surface to another inner surface of the cooling gallery. The partition extends circumferentially around the center axis, and divides the cooling gallery into at least a first gallery portion and a second gallery portion. The partition can be formed as one piece with the upper portion or the lower portion. Alternatively, the partition can be formed as a separate piece from the upper portion and the lower portion.

A piston capable of operating at a high temperature and consequently contributing to a high in-cylinder temperature, as well as reducing engine oil temperature, when used in an internal combustion engine, is provided. The piston includes an upper portion and a lower portion welded together to present a cooling gallery therebetween. The cooling gallery extends circumferentially around a center axis of the piston and is spaced the center axis. A partition is located in the cooing gallery and extends from one inner surface to another inner surface of the cooling gallery. The partition extends circumferentially around the center axis, and divides the cooling gallery into at least a first gallery portion and a second gallery portion. The partition can be formed as one piece with the upper portion or the lower portion. Alternatively, the partition can be formed as a separate piece from the upper portion and the lower portion.

An oil supply element for supplying oil into a cooling channel of a piston in an internal combustion engine, may include a channel having a lateral opening with an oil discharge element and may be configured to direct a partial oil flow via the oil discharge element and the lateral opening to at least one of an underside of a piston crown, a hub, and a piston interior.

A piston for an internal combustion engine may include a cooling duct having at least one feed opening. The piston may also include a feed funnel arranged within the at least one feed opening. The feed funnel may be fixed in the at least one feed opening via a blind rivet connection.

A piston for an internal combustion engine may include a cooling duct having at least one feed opening. The piston may also include a feed funnel arranged within the at least one feed opening. The feed funnel may be fixed in the at least one feed opening via a blind rivet connection.

A combustion-chamber structure of an engine comprises a combustion chamber which is partitioned by a cylinder block, a cylinder head, and a piston. The piston includes a piston body having an upper surface facing the combustion chamber, a heat-insulation layer provided at least in a central area, in a radial direction, of the upper surface and having smaller heat conductivity than the piston body, a heat-barrier layer provided to cover the upper surface and having smaller heat conductivity than the piston body and the heat-insulation layer, and a heat-diffusion layer provided between the heat-insulation layer and the heat-barrier layer and having larger heat conductivity than the heat-insulation layer and the heat-barrier layer. The heat-diffusion layer comprises a side end edge and an extension portion which contact with the piston body.

Methods and systems are provided for an oil gallery of a piston. In one example, a system for a piston comprising an internal oil gallery. The internal oil gallery comprises one or more of a funnel shaped inlet, a funnel shaped outlet, and a plurality of tongues extending along a circumference of the internal oil gallery.

Methods and systems are provided for an oil gallery of a piston. In one example, a system for a piston comprising an internal oil gallery. The internal oil gallery comprises one or more of a funnel shaped inlet, a funnel shaped outlet, and a plurality of tongues extending along a circumference of the internal oil gallery.