Soil moisture responsive irrigation flow control valve

摘要

A housing has at least one port for allowing entry of subterranean water into an interior of the housing when the housing is buried in soil. The housing has an inlet fitting configured to be coupled to drip tubing and an outlet for discharging water conveyed from a pressurized water source conveyed through the tubing. A valve includes a valve member that is movable to open and close a fluid communication path between the inlet fitting and the outlet. A hygroscopic member is positioned in the interior of the housing and is capable of absorbing subterranean water and expanding to move the valve member to close the fluid communication path. A spring element is positioned to bias the valve member to open the fluid communication path.

主权项

1. A drip irrigation system, comprising:
an irrigation controller; a plurality of solenoid actuated valves electrically connected to the irrigation controller and hydraulically coupled to a source of pressurized water; a plurality of moisture responsive flow control valves buried in the soil in different landscape zones, each moisture responsive flow control valve comprising a hygroscopic element configured to expand and shut off water flow through the moisture responsive flow control valve upon absorption of a predetermined amount of moisture; a plurality of sets of drip emitters, each set of drip emitters being connected to a corresponding one of the plurality of moisture responsive flow control valves; and each of the plurality of moisture responsive flow control valves connected to a corresponding one of a plurality of branch lines of drip tubing, each branch line being connected to a corresponding one of the solenoid actuated valves; wherein one or more of the moisture responsive control valves include:
a valve chamber in fluid communication with a water inlet of the moisture responsive control valve; anda flow control disc having positioned in the valve chamber, the flow control disc comprising:
an outer periphery;a first side facing the water inlet;a second side facing away from the water inlet;a recess in the second side through which water can bypass the flow control disc; andone or more notches in the outer periphery, the one or more notches forming one or more fluid flow paths between the water inlet and the recess.