GB278772A - Improvements in balanced valves - Google Patents

Abstract

278,772. Wagner, F. May 17, 1926. Valves controlled by pilot or relay valves.- A valve of the kind connected to a piston subject to conduit pressure under the control of a throttling device and auxiliary valve seating on the main valve, has a dog on the auxiliary valve spindle adapted to engage the main valve to prevent the main valve coming into contact with the throttling member. In the form shown in the Figure, the main valve 3 is formed integrally with a piston 32 adapted to work in a liner 31 provided with ports 8 leading to the inlet 13. Inlet pressure passes through tubes 12 to a chamber 9 and thence through a passage 16 to the actuating chamber 5 under the control of a throttling member 14. In the form shovrn, the passage 16 is partly conical and partly cylindrical, but a conical throttling member working in connection with a cylindrical passage may be used. The member 14 is carried by the spindle 7 of the auxiliary valve 4 which controls the exhaust from the chamber 5, which spindle also carries the dog 71 adapted to co-operate with a ported member 90 formed) on the chamber 9. The dog is arranged in the low pressure zone so that substantially equal pressures act on both sides. In a modification the dog is arranged in a high pressure zone and adapted to engage the underside of the upper part of the chamber 9.