Patent ID: 7997584

Claim:
A piston ring for a piston of an internal combustion engine having a piston crown, comprising: a ring joint; a side of the piston ring lying opposite the ring joint; and a circumferential chamfer that lies radially on an inside of the piston ring, a size of said chamfer decreasing symmetrically to an axis that lies radially and runs through the ring joint, on both sides of the ring joint, all the way to the side of the piston ring that lies opposite to the ring joint, wherein the chamfer is disposed on a lower side of the piston ring, which faces away from the piston crown, wherein the chamfer has a joint region on both sides of the ring joint, and a center region on a side of the piston ring that lies opposite to the ring joint; wherein a size of the chamfer in the joint regions and in the center region is constant, and is greater in the joint regions than in the center region, wherein each of the joint regions are connected with the center region by way of a connection region, wherein the chamfer has the size of the chamfer of the joint regions in connection regions at the contact locations with the joint regions, and the size of the chamfer of the center region at the contact locations with the center region, wherein the size of the chamfer in the connection regions constantly decreases, proceeding from the contact locations with the joint regions, all the way to the contact locations with the center region, and wherein a size of the center region, the connection regions and the joint regions is freely selectable so that a degree of twist of the piston ring in the region of the joint is equal to a degree of twist on an opposite side of the piston ring.