FIELD: mechanical engineering; two-stroke crosshead uniflow scavenging engine. SUBSTANCE: internal combustion engine has carbon scraper ring in cylinder and piston capable of moving in cylinder in longitudinal direction and furnished with piston rings sliding along inner surface of cylinder when piston is moved to form, together with pressure seal, separation between above-piston space and working chamber arranged above upper piston ring and set by upper piston ring, piston, inner surface of cylinder and cylinder cover. Carbon scraper ring projects from inner surface of cylinder, being arranged in such place along cylinder axis, that upper piston ring is located close to lower edge of carbon scraper ring when piston is in TDC. Several passage grooves are formed on cylindrical inner surface of carbon scraper ring. Grooves run with tilting relative to longitudinal axis of cylinder from lower surface of upper surface of carbon scraper ring. Passage grooves can be formed also in cylindrical outer surface of piston top arranged above upper piston ring. EFFECT: increased reliability. 18 cl, 6 dwg
