GB790894A - Closure device for tanks - Google Patents

Abstract

790,894. Covers for resisting fluid pressure. PARKER APPLIANCE CO. June 13, 1956, No. 18203/56. Class 123(1) A closure for preventing the escape of liquid which may leak past a spring-closed check valve 18 closing the filling and draining opening in the bottom, plate. 12 of a tank which may, for example, be the fuel tank of an aircraft with an underneath refuelling system, consists of a disc 33 provided with apertures 36 and a peripheral rubber-like sealing gasket 21 which engages the lower side 25 of an annular flange 17 defining the tank opening and upon which. the valve 18 bears. The disc 33 is brazed to an extensible bellows 31 the lower end of which is brazed to a circular plate 30 secured to a central pin 38 which protrudes through a central clearance hole in the disc 33, the plate 30 and the disc being held apart by a spring 47. Rotably mounted on the lower end of the pin 38 is an attaching cap 43 provided with bayonet lugs 52 engagable over bayonet lugs 22 on a skirt depending from the flange 17. When the closure device is in position the cap 43 is flush with the bottom plate 12 and the bellows is slightly compressed with the gasket 21 abutting the sealing surface 25 on the underside of the flange 17. If leakage occurs past the valve 18, the bellows fills with liquid and, since its outer diameter is greater than that of the contact line between the gasket 21 and seat 25. the liquid pressure urges the gasket into tighter sealing engagement with the seat to prevent escape of liquid.