Abstract: A piston ring includes a ring outer side, an upper ring flank and a lower ring flank, whereby the ring outer side has a pressure relief chamfer at an upper edge, so that only a lower part of the ring outer side forms a contact surface. An axial dimension of the contact surface varies in the circumferential direction.

Abstract: A stepped piston ring (2) includes a ring outer side (5), an upper ring flank (6), and a lower ring flank (8). The ring outer side (5) on the upper edge has a notch (10, so that only a lower portion of the ring outer side (5) forms a contact surface (4).

Abstract: A stepped piston ring (2) includes a ring outer side (5), an upper ring flank (6), and a lower ring flank (8). The ring outer side (5) on the upper edge has a notch (10, so that only a lower portion of the ring outer side (5) forms a contact surface (4).

Abstract: A piston ring has an annular base body 2, which is preferably open at a joint, with a U-shaped cross section, the open side of which faces inwards in the radial direction. A ring spring 4 is provided which runs in a meandering manner in the axial direction, and which pretensions the base body 2 outwards in the radial direction. In one section of the ring spring 4, which is located inside the base body, meandering loops 5 bear alternately against the shanks 3 of the U-shaped cross section. In one section of the ring spring 4, which protrudes out of the base body 2, meandering loops 6 bear alternately against the radially inwardly facing edges of the shanks 3 of the U-shaped cross section.