ELECTROPNEUMATIC VALVE Russian patent published in 1996 - IPC

FIELD: marine seismic exploration for accurate (in time) start of pneumatic sources of seismic signals. SUBSTANCE: electropneumatic valve has body, electromagnet, armature with pushers arranged in guide passages, movable lock with rod, cover and first-stage seat. Mounted on seat is spring-loaded locking member which may be engageable with pushers. Compressed air supply and discharge passages are provided in bottom of electropneumatic valve. Central hole coming to discharge passages is initially shut off with rod resting against second- stage seat. Located inside lock is piston with plunger which form intermediate chamber and control chamber together with cover which is connected with interior of valve through central hole in cover and is initially shut-off with locking member. Plunger rests against valve bottom retaining the clearance between lock and armature. EFFECT: enhanced efficiency. 1 dwg