| 摘要 |
The present invention relates to a piston assembly (1000A, 1000B, 2000) proceeding along a cylinder liner wall, the piston assembly: comprising a ring groove part (101c) into which a multifunctional ring (120) is inserted, wherein the multifunctional ring (120) isolates oil from air, instead of an oil ring, at the lower part of compression ring grooves (101a, 101b) into which a compression ring (110) is inserted; having a basket part (121) formed on the lower surface of the multifunctional ring (120) at a location facing a cylinder liner inner wall; and having a multifunctional ring groove provided at the lower part at which the final compression ring groove of a piston ends. |
