Composite oil-ring

A composite oil-ring comprising an oil control ring disposed on a lower surface of an oil-ring groove, a seal ring disposed on the oil control ring and having substantially no oil path in the radial direction thereof, and a spring seal ring disposed between an upper surface of the oil-ring groove and the seal ring which is constituted as a Belleville spring structure having abutted end portions with no gap in the circumferential direction. The spring seal ring presses upwards against the upper surface of the oil-ring groove and presses downwards against the seal ring, the seal ring is pressed against the oil control ring, and the oil control ring is pressed against the lower surface of the oil-ring groove, by the spring force of the spring seal ring. Both the spring seal ring and seal ring have substantially no oil path in the radially outer direction. Therefore, the oil in the interior of the oil-ring groove can be prevented almost completely from escaping in both radially outward and axially upward directions. As a result, the oil loss through the composite oil-ring can be suppressed to very small value, thereby decreasing oil consumption to a great extent.