Abstract: The running face of a compression piston ring also having an inner circumferential surface, and upper and lower flank surfaces interposed between the running face and the inner circumferential surface is provided, in a region thereof adjacent the lower flank, with a first taper of less than 30?, having an axial height of 10 to 30%, based on the total running face height (H), the first taper transitioning into a second taper extending in the direction toward the upper flank surface, which is between 90? and 200?, and the running face is also provided with a thin wear-resistant layer having a thickness from 0.1 to less than 20 ?m, and in particular 4 to 6 ?m.

Abstract: The running face of a compression piston ring also having an inner circumferential surface, and upper and lower flank surfaces interposed between the running face and the inner circumferential surface is provided, in a region thereof adjacent the lower flank, with a first taper of less than 30?, having an axial height of 10 to 30%, based on the total running face height (H), the first taper transitioning into a second taper extending in the direction toward the upper flank surface, which is between 90? and 200?, and the running face is also provided with a thin wear-resistant layer having a thickness from 0.1 to less than 20 ?m, and in particular 4 to 6 ?m.

Abstract: A piston ring is provided in the form of a base body, which has a running face, an inner circumferential surface, and upper flanks and lower flanks interposed therebetween, in which the base body has a joint and an edge relief, in particular in the region of the inner circumferential surface thereof, and wherein the running face, seen in the circumferential direction, is provided with changing running face conicities and/or convexities, such that a lesser running face conicity and/or convexity exists in the region of the joint than in the diametrically opposed ring back.

Abstract: A multi-part piston ring, containing an at least single-part spring support which is provided with a piston ring joint region and an at least single-part spring element, which is positioned in a groove provided in the region of the inner circumferential face of the spring support, wherein the wall thickness of the spring support is essentially equal in the region of the ends of the spring support facing the piston ring joint and in the rear region of the spring support, and a pocket which extends over a circumferential range of at least 60° and is created by local reduction of the wall thickness of the spring support is provided in each case between the rear region and the piston ring joint ends.

Abstract: A multi-part piston ring, containing an at least single-part spring support which is provided with a piston ring joint region and an at least single-part spring element, which is positioned in a groove provided in the region of the inner circumferential face of the spring support, wherein the wall thickness of the spring support is essentially equal in the region of the ends of the spring support facing the piston ring joint and in the rear region of the spring support, and a pocket which extends over a circumferential range of at least 60° and is created by local reduction of the wall thickness of the spring support is provided in each case between the rear region and the piston ring joint ends.