PISTON SEALING DEVICE Russian patent published in 1998 - IPC

FIELD: sealing technology; sealing pistons of machines and mechanisms. SUBSTANCE: device includes two rings concentrically located in piston groove and expander made in form of stack of spiral springs. Working piston ring has grooves on inner cylindrical surface; grooves have inclined surfaces receiving wedge-shaped projections of additional ring. Cylindrical springs located between surfaces of projections and grooves located in radial planes act on piston ring making it interact with additional ring over inclined surfaces of grooves and projections, move away from additional ring and get pressed against cylinder face, thus creating sealing effect of device. EFFECT: enhanced efficiency of sealing. 3 dwg