Image Number 3 for United States Patent #5769124.
A water supply system for an aircraft includes a ventilatable water tank, a water supply line to supply water to water-using devices such as galleys and handwash basins, fill and drain lines, and a multi-function valve for carrying out filling and draining, and other system functions. The multi-function valve is interposed between the water tank, the water supply line, the fill line, and the drain line. The valve includes a filling port connected to the filling line, a tank port connected to the water tank, a supply port connected to the supply line, a drain port connected to the drain line, and preferably also a tank overflow port and an outside overflow port. The valve includes a shut-off element arranged within a housing, wherein the shut-off element has therein a water passage which includes first, second, and third branches, and preferably also an air passage. The valve can be operated to switch the valve selectively into a normal operating position, a closed or shut-off position, a fill and drain position, or a total drain position. The multi-function valve replaces a plurality of individual valves, thereby reducing the number of components and the total weight of the system, and the time and costs for installation.