Manifold drain valve

Claim 1

A LIQUID DRAIN VALVE ADAPTED TO BE CONNECTED IN A FUEL SYSTEM BETWEEN A METERED FUEL SUPPLY SOURCE AND A MANIFOLD OR LIKE DISCHARGE LINE TO CONTROL DRAINAGE FROM SAID DISCHARGE LINE TO A LOW PRESSURE DRAIN LINE, SAID VALVE COMPRISING A BODY HAVING INTAKE AND DISCHARGE PASSAGES ADAPTED TO BE CONNECTED RESPECTIVELY TO SAID SOURCE AND DISCHARGE LINE, A VALVE PASSAGE IN SAID BODY THROUGH WHICH SAID PASSAGES MAY COMMUNICATE, SAID VALVE PASSAGE BEING PROVIDED WITH A VALVE SEAT, A SHIFTABLE VALVE MEMBER IN SAID VALVE PASSAGE CONTROLLING FLOW ACROSS SAID VALVE SEAT AND OUT OF ENGAGEMENT WITH THE LATTER UNDER NORMAL OPERATING PRESSURE FROM SAID SOURCE, A CHAMBER IN SAID BODY LATERAL TO SAID VALVE PASSAGE AND IN COMMUNICATION WITH SAID INTAKE PASSAGE UNDER PRESSURE IN THE LATTER AND IN PART DEFINED BY A MOVABLE WALL, SAID BODY HAVING DRAINAGE PASSAGE MEANS ADAPTED TO COMMUNICATE SAID DISCHARGE PASSAGE AND DRAIN LINE, SAID DRAINAGE PASSAGE MEANS BEING CONTROLLED BY A PART OF SAID MOVABLE WALL TO OPEN AND CLOSE COMMUNICATION OF SAID DISCHARGE PASSAGE WITH SAID DRAINAGE PASSAGE MEANS FROM A POINT DOWNSTREAM OF SAID VALVE SEAT, RESILIENT MEANS RESPECTIVELY BIASING, WITH GREATER AND LESSER FORCE, SAID VALVE MEMBER AGAINST SAID VALVE SEAT AND SAID MOVABLE WALL IN A DIRECTION TO CAUSE SAID PART OF THE LATTER TO OPEN SAID DRAINAGE PASSAGE MEANS, SAID RESILIENT MEANS ACTING IN EACH CASE AGAINST FLUID PRESSURE IN SAID COMMUNICATED INTAKE PASSAGE AND CHAMBER, AND A BLEED PASSAGE BYPASSING SAID VALVE MEMBER TO COMMUNICATE SAID INTAKE PASSAGE AND CHAMBER WITH SAID DISCHARGE PASSAGE AND SAID DRAINAGE PASSAGE MEANS FOR THE RAPID DROPPING OF PRESSURE IN SAID INTAKE PASSAGE AND CHAMBER WHEN NORMAL OPERATING PRESSURE FROM SAID METERED FUEL SUPPLY SOURCE IS DISCONTINUED.