INTERNAL COMBUSTION ENGINE PISTON SEALING Russian patent published in 2004 - IPC

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: fitted in piston groove of engine piston are lower compression ring and upper stepped split flexible ring with its joint arranged at angle of 180^o relative to split of lower ring joint. Minimum required clearance is provided between step of upper ring and corresponding projection in cavity made on upper flange of piston groove to provide tight contact between outer surface of stepped ring and cylinder linear at initial period of operation. Arrangement of split of stepped ring joint at 180o relative to splint of lower ring joint precludes direct blowby of working pressure into piston groove and further on into engine crankcase by means of stepped ring. In process of testing and running-in of engine owing to friction of outer surface of stepped ring against cylinder linear, clearance between step of ring and projection in cavity of upper flange of piston groove is eliminated, and least possibility of leakage of working medium is prevented. Proposed piston sealing considerably decreases leakage of working gases, reduces mechanical friction losses, increases efficiency and effective power output of engine and its service life, improved ecological characteristics of engine.

EFFECT: simple design, easy to manufacture.

1 dwg