CYLINDER-PISTON Russian patent published in 2002 - IPC

FIELD: mechanical engineering; piston machines; internal combustion engines. SUBSTANCE: proposed cylinder-piston group consists of piston with fitted-on piston rings in contact with working surface of linear. Grooves are made on inner surface of linear consisting of two screw lines with right- hand and left-hand thread, respectively. Screw lines of groove are filled up with nonferrous metal (alloy) with angle of helix within 15^°≤ϕ≤60^°, and pitch not exceeding distance between upper compression and lower oil control rings H<L. EFFECT: increased service life of cylinder-piston group owing to decrease of coefficient of friction of mating parts without introduction of expensive antifriction additives into lubricating oil. 2 dwg