| 摘要 |
PURPOSE: A structure of a piston ring for reducing quantity of blow-by gas is provided to reduce quantity of discharged blow-by gas, and to delay deterioration of oil. CONSTITUTION: A stepped protrusion(14) is formed on an inner upper end of a first ring groove(12) to which a top ring(10) is coupled, and a stepped part(15) is formed on an inside of the top ring correspondingly with the stepped protrusion to reduce weight of the top ring so as to reduce time needed for the top ring to be lifted up when piston is moved down as inertia force of the top ring is reduced. An inner side clearance(C1) between the stepped protrusion and the stepped part is formed to be smaller than an outer side clearance(C) between the top ring and the first ring groove to reduce height by which the top ring is lifted up. A stepped groove(16) is formed on an inside of a second ring(11) to increase volume of a space of a second ring groove(13) to which the second ring is inserted so as to reduce pressure of gas between the top ring and the second ring.
|
