CHECK VALVE FOR VACUUM PIPE LINE Russian patent published in 1994 - IPC

FIELD: pipe line fittings. SUBSTANCE: shutoff member is mounted on side of inlet pipe union of housing. Diaphragms of various diameters are secured on bearing disk having through hole. Valve made in form of movable sleeve is mounted coaxially relative to outlet pipe union. Bearing disk is spring-loaded towards shut-off member. Through hole in disk is coaxial relative to valve and shut-off member which are engageable in turn with disk during operation of valve. Inner chamber formed by diaphragms and disk is brought in communication with atmosphere. EFFECT: enhanced reliability. 1 dwg