GB1505111A - Apparatus for permitting the filling of a liquid reservoir without overflow - Google Patents

Abstract

1505111 Filling fuel reservoirs without overflow VOLUCOMPTEURS ASTER BOUTILLON 18 Feb 1975 [18 Feb 1974 16 April 1974 30 Jan 1975] 6751/75 Heading B8T [Also in Division F2] Apparatus which prevents the overfilling of, e.g., an underground petrol tank, but which allows complete emptying of the filling conduit comprises: an automatically operated level responsive valve which closes or restricts the liquid flow path when the level reaches a certain level within the tank; an upstream valve which is manually closed when the automatic valve is moved to its closed or flow restricting position; and an arrangement whereby the pressure in the filling conduit between the valves is reduced so that the automatic valve opens if it was closed or reduces the amount of flow restriction whereby the conduit is emptied. The valve is damped to prevent banging. In a form where the automatic valve completely closes the filling conduit the pressure is reduced by opening a small branch line located in the conduit between the valves. The automatic valve is operated by a float, Figs. 1-6 (not shown). In another form the pressure is reduced by providing permanently open bleed lines through and/or by-passing the automatic valve such that the pressure on both sides of the automatic valve are equalized. The valve then re-opens under the action of the torque from the float which is mainly above the liquid level, Fig. 7 (not shown). In another form, Fig. 13, the automatic lever valve 85 comprises auxiliary first and second secondary valves 89, 94 both linked to the float. When the float reaches a certain level it acts via a lever linkage to pull on spring 83 and flexible wire 84 such that automatic valve 85 and first auxiliary valve 89 close against their respective springs. The liquid level and float continue to rise until the second auxiliary valve 94 slides on post 97 and closes aperture 88 in valve 85. The only possible flow left is through the aperture 98 and via any by-pass bleed lines (not shown) The upstream manually operated valve being closed at this stage allows a relatively slow reduction in pressure through the apertured disc 94 and any bleed lines such that first auxiliary valve 89 reopens to allow conduit emptying after the manual valve is re-opened slowly. If, however, it is forgotten to close the manually operated upstream valve further tension in spring 83 causes a plate 102 to block the aperture 98 in disc 94 and prevent further filling. The automatic valve may be damped by a counterweight float or by a fluid filled bellows between it and its valve seat. A line 106 is closed by valve 109 during filling but allows air to flow from line 29 during emptying of the conduit.