Patent GB-699316-A (GB)
Title: Improvements relating to apparatus for supplying liquid
Inventor: WOOLDRIDGE JAMES ARTHUR
IPC: F04F5/52
Filed: 1951-07-12
Abstract: 699,316. Filling and emptying tanks. SHELL REFINING & MARKETING CO., Ltd. June 5, 1952 [July 12, 1951], No. 16544/51. Class 21 [Also in Groups XVIII and XXVIII] In apparatus for supplying liquid under pressure from a supply source to a container (e.g. the fuel tank of an aircraft) through a pipeline system, a predetermined vacuum is maintained in an auxiliary container by an eductor connected in and operated by the flow of liquid into the main container, under control of a by-pass valve across the eductor regulated by a piston and cylinder connected to the auxiliary container vacuum, a duct connects the auxiliary vacuum container through a control valve to the pipeline system and/or the main container, and valves are provided for isolating the supply source, whereby the liquid may be withdrawn as required from the pipeline and/or main container into the auxiliary container after a supply operation, and from thence to the main line through the eductor during the next supply operation. Fig. 4 shows a fuel-dispensing system for aircraft in which reels 38, 39 mounted on a truck 37 carry hoses which are respectively coupled through automatic valves to a dispersing point 46 of a static pipe system, and to the tank of the aircraft through its internal pipework. The hoses are interconnected on the truck through a pressure control valve 41 of the kind described in Specification 668,451, [Group XXIX], a controlled eductor 1, a filter 42, and air eliminator 43, and a meter 44, while an auxiliary container 15 in which a controlled vacuum is maintained by the eductor is conneoted to the system between the filter and the air eliminator through a control valve 27A Figs. 1, 2 show the controlled eductor system, which is connected as a by-pass across a butterfly fuel valve 3 in the main fuel line tending to be closed by the liquid flow, to create a vacuum in the container 15 through a non-return valve 5 and pipe 4. The butterfly valve is controllable through a linkage 7, 8, by a springloaded piston 9 moving in a cylinder 10 so as to close the butterfly valve when atmospheric pressure prevails on both sides of the cylinder. The latter is connected through a leaking non-return valve 22 to a port 21 of the cylinder 17 of a pilot valve 13, which is also ported through a pipe 14 to the vacuum container. A spring- loaded plunger 16 within the cylinder 17 has a port 25 connected to atmosphere through a central bore 26 and a lower port 23 connected by a peripheral channel 24 to pipe 14 and through an axial channel 19 to the space within the cylinder. Initially plunger 16 is positioned so that cylinder 10 is connected to atmosphere through ports 21, 25 and valve 22. Valve 3 is closed and the pressurized fuel flow to the aircraft is diverted through eductor 1, whereby vacuum is developed in container 15. Plunger 16 rises against its spring, and at a predetermined container vacuum connects cylinder 10 to vacuum through ports 21, 23 and channel 24, and non- return valve 22, which closes but leaks so that after a time delay, the vacuum in the cylinder suffices to open valve 3 and reduce the eductor suction so as to just maintain the predetermined vacuum. On completion of the supply operation, the hoses are disconnected, whereupon their automatic valves close so that on opening valve 27A the fuel in the system is sucked back into the container 15, any fuel which has passed the motor traversing it in the reverse direction. The delivery hose may be left attached to the aircraft whereby fuel may be sucked from pipelines and/or tanks therein. During the subsequent fuelling operation, the fuel accumulated in the container 15 is drawn by the eductor into the main delivery stream. Fig. 3 shows a modified pilot valve for preventing air leaks wherein a ported airtight sleeve surrounds the springloaded plunger 16, and projects beyond the cylinder bore so as to be sealed by a resilient washer fixed to the plunger when vacuum is applied to the cylinder 17 and the plunger moves to the right. The central bore 26 venting to atmosphere is also closed by a spring-loaded valve 31, which is opened by projection 34 when atmosphere is applied to the cybinder 17 and the plunger moves to the left. The atmospheric inlet 35 has a dust filter 36.