A steel piston (1) for a combustion engine, having an upper part in which a ring section (7) with at least one ring groove (8) is arranged, wherein the upper part is adjoined by a lower part that has two opposing skirt wall sections (2), wherein the two skirt wall sections (2) are connected via two mutually opposite case walls (3), wherein a pin bore (4) surrounded by a piston boss (6) is provided in each case wall (3). In one example, there is at least one aperture (14) or at least one recess in the case wall (3) in the region between the piston boss (6) and the skirt wall section (2).

A piston may have an annular body including a crown portion defining a longitudinal axis, a radial direction perpendicular to the longitudinal axis, a plane containing the longitudinal axis and the radial direction, and a contoured combustion bowl. In the plane containing the longitudinal axis and the radial direction, the crown portion includes a radially outer squish surface, and a swirl pocket having a reentrant surface that extends axially downwardly and radially outwardly from the squish surface defining a tangent that forms a reentrant angle with the squish surface that ranges from 33.0 degrees to 37.0 degrees.

A piston for an internal combustion engine may include a lower piston part, a combustion chamber bowl part, and a ring section part. The lower piston part, the combustion chamber bowl part, and the ring section part may be welded together. The piston may include a first ring collar arranged on the combustion chamber bowl part. The piston may include a second ring collar arranged on the ring section part. The first and second ring collar may abut on one another and separate a first air insultation chamber from a coolant channel.

A piston for an internal combustion engine may include a lower piston part, a combustion chamber bowl part, and a ring section part. The lower piston part, the combustion chamber bowl part, and the ring section part may be welded together. The piston may include a first ring collar arranged on the combustion chamber bowl part. The piston may include a second ring collar arranged on the ring section part. The first and second ring collar may abut on one another and separate a first air insultation chamber from a coolant channel.

The invention relates to a piston for an internal combustion engine formed from a lower part and an upper part which are threadingly connected to one another to form a piston. In one example, an anti-rotation safeguard device is used to prevent unwanted rotation of the upper part relative to the lower part. In another example, a forged extension and a nut are used to obtain a prestress during operation of the piston. In another example, a cooling gallery including extension bores are used to increase the cooling capacity.

An engine piston having a piston upper part, a piston lower part connected to the piston upper part, a piston pin mounted in the piston lower part connects the piston to a connecting rod, and a first cooling space between the piston upper and lower parts for cooling oil. The first cooling space is connected to a second cooling space formed between the piston upper part and a piston lower part via at least one transfer bore, a cooling oil conduction sleeve for conducting cooling oil through a bore in the connecting rod towards the first cooling space. A guiding surface of the cooling oil conduction sleeve adjoins a support face of the piston lower part. At least one groove circulating in the circumferential direction is introduced into the guiding surface of the cooling oil conduction sleeve and/or into the support face of the piston lower part.

An engine piston having a piston upper part, a piston lower part connected to the piston upper part, a piston pin mounted in the piston lower part connects the piston to a connecting rod, and a first cooling space between the piston upper and lower parts for cooling oil. The first cooling space is connected to a second cooling space formed between the piston upper part and a piston lower part via at least one transfer bore, a cooling oil conduction sleeve for conducting cooling oil through a bore in the connecting rod towards the first cooling space. A guiding surface of the cooling oil conduction sleeve adjoins a support face of the piston lower part. At least one groove circulating in the circumferential direction is introduced into the guiding surface of the cooling oil conduction sleeve and/or into the support face of the piston lower part.

The present invention refers to a piston for an internal combustion engine, particularly a V-engine. The piston comprises an oil drainage groove provided in the outer circumferential surface of the piston between a ring belt and a piston skirt of the piston, the piston skirt being provided with two recessed pin boss portions on opposed sides of the piston, wherein the piston skirt is further provided with at least one oil drainage duct arranged between the two recessed pin boss portions at an outer surface of the piston skirt and configured to fluid-communicatively connect the oil drainage groove with the recessed pin boss portions.

The present invention refers to a piston for an internal combustion engine, particularly a V-engine. The piston comprises an oil drainage groove provided in the outer circumferential surface of the piston between a ring belt and a piston skirt of the piston, the piston skirt being provided with two recessed pin boss portions on opposed sides of the piston, wherein the piston skirt is further provided with at least one oil drainage duct arranged between the two recessed pin boss portions at an outer surface of the piston skirt and configured to fluid-communicatively connect the oil drainage groove with the recessed pin boss portions.

A one-piece cast piston (10) for an internal combustion engine includes a cooling channel (12) and at least one rib (18) on the inner side of the piston opposite the recess base of a combustion bowl (14).