TWO-WAY HYDRAULIC LOCK Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: two-way hydraulic lock has housing 1 and check valves 2 and 3 mounted in its central axial bore. Valves 2 and 3 have seats 4 and 7 and spring-loaded adjusting members 6 and 9. Central control member is made in form of two pistons 16 and 17 with unloading chamber 18 formed in between them. Chamber 18 is connected with drain line. Pistons 16 and 17 are spring-loaded relative to housing 1 on side of unloading chamber 18. Motion of piston 16 on side of control chamber 19 is limited with stop 24 and motion of piston 17 on side of control chamber 20 is limited with stop 26. Tappet 27 is mounted in hole of piston 16 bringing one its end in contact with piston 17 and other end in contact with shut-off adjusting member 6 of check valve 2. Tapper 28 is mounted in hole of piston 17 bringing it in contact with piston 16 and with shut-off adjusting member 9 of check valve 3. Seats 4 and 7 check valves are adjustable in position in axial direction of central bore in housing 1. EFFECT: enhanced efficiency. 2 cl, 1 dwg