INTERNAL COMBUSTION ENGINE PISTON SEAL (VERSIONS) Russian patent published in 2010 - IPC F02F5/00 

FIELD: engines and pumps.

SUBSTANCE: proposed piston seal comprises upper split flexible stepped ring that rests upon outer circular ledge made on top shoulder of piston groove, and lower compression ring fitted in the same groove. Stepped ring is arranged to make a clearance between its outer edge and engine cylinder wall. In compliance with the first version, clearance between top edge of stepped ring extension and bottom edge of aforesaid circular ledge exceeds the gap between top edge of stepped ring and upper ledge of piston groove. In compliance with the second version, stepped ring top face has at least two circular recesses that form circular ledges. Piston groove top shoulder has circular ledges that enter appropriate circular recesses of stepped ring to form labyrinth seal. Circular ledges test upon appropriate circular ledges on piston groove top shoulder.

EFFECT: reduced penetration of high-temperature gases into piston groove bottom area and minor engine oil oxidation process.

3 cl, 2 dwg