Patent ID: 8876115

Claim:
A three-piece oil control ring for use in a piston groove of an internal combustion engine, said ring comprising: a first annular segment ( 2 ); having a first end facing the internal wall of the piston groove; and a second annular segment ( 3 ), parallel to and spaced apart a first distance from the first annular segment ( 2 ) and having a first end facing the internal wall of the piston groove, said first and second annular segments ( 2 , 3 ) being associated with an expanding element ( 4 ), said expanding element ( 4 ) having a substantially annular shape and comprising a first end ( 4 a ) facing the internal wall of the piston groove when the ring is mounted on the piston and a second opposite end ( 4 b ), wherein: the expanding element ( 4 ) further comprises a substantially intermediate portion ( 5 ) positioned intermediate the first end ( 4 a ) and the second opposite end ( 4 b ) of the expanding element, said substantially intermediate portion ( 5 ) comprising at least two protrusions ( 5 a , 5 b ), at least a portion of each of the at least two protrusions being in contact with the first ends of the first and the second annular segments ( 2 , 3 ), respectively; the first end ( 4 a ) exhibits a first thickness value (E 1 ), the second end ( 4 b ) exhibits a second thickness value (E 2 ) and the substantially intermediate portion ( 5 ) exhibits a third thickness value (E 3 ), third thickness value (E 3 ) being greater than the first distance such that a portion of the at least two protrusions ( 5 a , 5 b ) contacts the first ends of the first and the second annular segments ( 2 , 3 ), respectively; the value (E 1 ) is substantially lower than the value (E 3 ) and at least one of lower or similar to the value (E 2 ); and a difference between the value (E 1 ) and the value (E 3 ) is substantially higher than the a difference between the value (E 1 ) and the value (E 2 ).