Piston assembly for internal combustion engine - has separate compression and oil scraper rings with radial, elastic, thin abutting flaps

摘要

The piston (11) of a compressor or internal combustion engine is fitted with dual compression rings (12) and a separate scraper ring (13). One compression ring is made of metal and with its radial width considerably greater than its axial thickness. The ring has a number of notches around its inner edge to increase its elasticity. The ring is fitted in the piston groove with a circular lip abutting against the cylinder together with a flat ring of PTFE. The scraper ring (13) is of L shaped cross-section and made of spring steel. The surface abutting against the cylinder wall (14) is divided into a number of circumferentially abutting thin elastic flaps.