Min. water level control for reservoir - has float controlled outlet valve closed by lack of pilot flow from reservoir

摘要

The reservoir is connected to an intermediate tank by a pipe with a float controlled valve in the tank. This tank connects with a further tank by a similar pipe (10) with a cylindrical valve stopcock (13) controlled by float (14). Above this float and connected to it is a container (17) whose internal volume is slightly greater than that of the immersed portion of the float (14) and which is supplied by water direct from the reservoir by a pipe (18) whose inlet is located in the reservoir at the level below which water must not fall. When water in the reservoir drops below the inlet level of this pipe (18), the container (17) becomes empty, raising float (14) and closing the cylindrical valve (13).