The present disclosure provides a sealing ring assembly with one or more piston-integrated gap cover features, configured to seal a high-pressure region from a relatively lower pressure region of a piston and cylinder device. The sealing ring assembly may include two rings which each may include one or more ring segments. The one or more gap-cover features, which may be in the form of protrusions in the piston ring groove, may engage with corresponding flat sections of the ring segments. As the sealing ring wears, the gap-cover features may stay engaged with the ring segments, thereby maintaining a seal.

A piston ring set for internal combustion (IC) engine is provided. The IC engine includes a cylinder having a liner and a finish on the liner. A piston having a crown and a set of grooves is disposed in the cylinder. A set of piston rings is disposed in the set of grooves. The piston rings are disposed in order from closest to the crown and include at least a first compression ring having free ends defining a first end gap, a second compression ring having free ends defining a second end gap. A nominal value of the first end gap of the first compression ring is greater than a nominal value of the second end gap of the second compression ring.

The oil control ring (2) extends in a circumferential direction (2x) about a center (2l) and has a longitudinal axis (2m) that passes through the center (2l), wherein the oil control ring (2) has an end face (2d) that faces the center (2l), and wherein the oil control ring (2) has a first lateral surface (2s), a second lateral surface (2t), and an outer surface (2u) facing away from the center (2l), wherein the oil control ring (2) has a plurality of channels (2c) extending toward the center (2l) on the first lateral surface (2s), said channels being arranged at mutual distances in the circumferential direction (2x) and extending over the entire width of the first lateral surface (2s) in the radial direction and thereby forming a fluid-conducting connection between the end face (2d) and the outer surface (2u), and wherein crown parts (2i) extending in the circumferential direction (2x) are arranged between pairs of channels (2c), wherein each crown part (2i) protrudes beyond the respective channel (2c) in the direction of extent of the longitudinal axis (2m) and forms a lateral channel surface (2w) for the channel (2c), wherein at least one of the crown parts (5i) is designed as a long crown part (2p) and extends over an angular range (α) between 60 degrees and 350 degrees in the circumferential direction (2x). 212×2121.

The oil control ring (2) extends in a circumferential direction (2x) about a center (2l) and has a longitudinal axis (2m) that passes through the center (2l), wherein the oil control ring (2) has an end face (2d) that faces the center (2l), and wherein the oil control ring (2) has a first lateral surface (2s), a second lateral surface (2t), and an outer surface (2u) facing away from the center (2l), wherein the oil control ring (2) has a plurality of channels (2c) extending toward the center (2l) on the first lateral surface (2s), said channels being arranged at mutual distances in the circumferential direction (2x) and extending over the entire width of the first lateral surface (2s) in the radial direction and thereby forming a fluid-conducting connection between the end face (2d) and the outer surface (2u), and wherein crown parts (2i) extending in the circumferential direction (2x) are arranged between pairs of channels (2c), wherein each crown part (2i) protrudes beyond the respective channel (2c) in the direction of extent of the longitudinal axis (2m) and forms a lateral channel surface (2w) for the channel (2c), wherein at least one of the crown parts (5i) is designed as a long crown part (2p) and extends over an angular range (α) between 60 degrees and 350 degrees in the circumferential direction (2x). 212×2121.

A play-free oil scraper ring has a cross section with a running surface leg having at least one scraper web that is situated on a running surface, an upper piston ring flank leg that is connected to the running surface leg, and the upper surface of which forms an upper piston ring flank. A lower piston ring flank leg is likewise connected to the running surface leg, the lower surface of which forms a lower piston ring flank. The upper and/or the lower piston ring flank leg are/is elastic, taper(s) inwardly in the radial direction, and their/its piston ring flank(s) essentially form(s) a conical surface in an uninstalled state. The uninstalled piston ring has an axial height that exceeds a width of a piston ring groove for which the piston ring is intended.

A cylinder of an internal combustion engine, having a cylinder liner and a cylinder piston guided in the cylinder liner The cylinder piston has multiple ring grooves delimited by ring webs and are separated by the ring webs. Each ring grooves receives a compression ring or an oil scraping ring. Each ring groove is delimited by an upper groove flank, a lower groove flank and a groove base, and each piston ring has a lower ring flank, an upper ring flank a ring back and a section which rests against a radially inner running surface of the cylinder liner. A depression is introduced into the lower groove flank of the at least one ring groove or each ring groove which receives a compression ring and/or into the lower ring flank of the piston ring designed as a compression ring.

A piston ring is provided, in particular a compression piston ring having at least one recess with a lower edge running obliquely to the upper piston ring flank on its upper piston ring flank, the ring flank extending radially outward from the piston ring interior and radially inward from the piston ring bearing surface. The piston ring has a chamfer, which is opposite at least one recess. At least one recess and the chamfer extend in the radial direction up to at most the center of the cross-sectional area of the piston ring.

A piston ring is provided, in particular a compression piston ring having at least one recess with a lower edge running obliquely to the upper piston ring flank on its upper piston ring flank, the ring flank extending radially outward from the piston ring interior and radially inward from the piston ring bearing surface. The piston ring has a chamfer, which is opposite at least one recess. At least one recess and the chamfer extend in the radial direction up to at most the center of the cross-sectional area of the piston ring.

An engine includes a housing and a combustion assembly. The combustion assembly includes an annular bore and a combustion piston assembly disposed within the annular bore. The combustion piston assembly includes a set of pistons, a first sealing ring connected to each piston and a second sealing ring connected to each piston. The second sealing ring is configured to provide selective access between the annular bore and at least one fluid conduit carried by the engine. The engine includes at least one valve configured to move between a first position within the annular bore to allow the combustion piston assembly to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position within the annular bore to define a combustion chamber.

An engine includes a housing and a combustion assembly. The combustion assembly includes an annular bore and a combustion piston assembly disposed within the annular bore. The combustion piston assembly includes a set of pistons, a first sealing ring connected to each piston and a second sealing ring connected to each piston. The second sealing ring is configured to provide selective access between the annular bore and at least one fluid conduit carried by the engine. The engine includes at least one valve configured to move between a first position within the annular bore to allow the combustion piston assembly to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position within the annular bore to define a combustion chamber.