Patent ID: 9097202
Filing Date: 2015-08-04
Classification: F02F,Y10T

Abstract:
1. A piston for an internal combustion engine, comprising: a piston crown connected to and above a body portion of the piston, the body portion forming two pin bores, and the piston crown defining an outer cylindrical wall; at least one piston ring seal groove formed in the outer cylindrical wall and extending peripherally around the piston crown, the at least one piston ring seal groove being configured to accommodate therein a piston ring seal; a first oil drainage groove formed in the outer cylindrical wall below the at least one piston ring seal groove and extending in parallel to the at least one piston ring seal groove around an entire periphery of the piston, wherein the first oil drainage groove has a first width measured along a centerline of the piston; a plurality of drain openings formed in the body portion, the plurality of drain openings fluidly connecting the first oil drainage groove with an internal gallery of the piston; a second oil drainage groove formed in the outer cylindrical wall below and adjacent the first oil drainage groove, the second oil drainage groove defining a first channel, a second channel, and an annular protrusion disposed between the first channel and the second channel, the annular protrusion defining a reduced-diameter land portion; wherein the second oil drainage groove extends parallel to the first oil drainage groove around the entire periphery of the piston but is interrupted over segments of the body portion that accommodate the two pin bores such that oil collected in the second oil drainage groove drains from the first channel to the second channel, and from the second channel back to the internal combustion engine through the segments and externally to the piston, wherein the second oil drainage groove has a width that is wider than the width of the first oil drainage groove; and at least one additional piston ring groove being sized to receive a piston ring seal therein, the at least one additional piston ring groove disposed adjacent the at least one piston ring seal groove.