Lawn sprinkling and similar installations

Claim 1

A sprinkling or similar liquid-distribution installation comprising a plurality of dosing valves each having an inlet and first and second outlets, a liquid supply pipe connected to the inlet of a first dosing valve, a gate valve controlling the delivery of liquid through said supply pipe, the first outlet of each dosing valve being connected in operation to at least one sprinkler, piping connecting the second outlet of each dosing valve except a last dosing valve being to the inlet of a next sequential dosing valve, a plug in the second outlet of said last dosing valve, means having an orifice for discharging liquid from said piping connecting the dosing valves, said orifice communicating with the exterior to discharge liquid from said piping after closing of said gate valve, after closing of the first outlet of said last dosing valve, each dosing valve including a clapper, means for biasing the clapper to close the second outlet and leave the first outlet open, volumetric dosing means for closing the first outlet and simultaneously opening the second outlet after passage of a given quantity of liquid, said volumetric dosing means including a pusher having a first advanced position after passage of said given quantity of liquid in which first position it holds said clapper against the action of said biasing means to open said second outlet orifice and close said first outlet orifice, and a second withdrawn position in response to a drop in the pressure in said piping after opening of said discharge outlet, in which second position said pusher allows the clapper to move under the action of said biasing means to close said second outlet orifice and open said first outlet orifice.