COMPOSITE PISTON RING

FIELD: machine building. ^ SUBSTANCE: invention refers to the sphere of compaction machinery. The composite piston ring is composed of a set of circular segments fabricated of hard friction-resistant materials, laid in the piston groove, pressed against the cylinder face with a spring-loaded expander and joined to each other via the connector locking end planes. The circular segments are arranged in a single layer and in pairs symmetrical and opposite to each other relative to the piston coordinate symmetry axes. With one of the circular segment pairs the locking end planes are positioned at an angle of 10-25° relative to the piston vertical symmetry axis; with the other circular segment pair they are positioned at an angle of 60-80° relative to the piston horizontal symmetry axis. The spring-actuated expander is represented by a flat band spiral-coiled and laid between the circular segments and the inner cylindrical surface of the piston groove. ^ EFFECT: sealant reliability improvement. ^ 3 cl, 5 dwg