Patent ID: 8371325
Filing Date: 2013-02-12
Classification: F16K,Y10T

Abstract:
1. A soil moisture responsive irrigation flow control valve, comprising: a housing having at least one port for allowing entry of subterranean water into an interior of the housing when the housing is buried in soil and having an inlet fitting configured to be coupled to drip tubing for receiving water conveyed from a pressurized water source through the tubing and an outlet for discharging water to the soil; a valve including a valve member movable to open and close a fluid communication path between the inlet and the outlet; a hygroscopic member positioned in the interior of the housing capable of absorbing subterranean water and expanding to move the valve member to close the fluid communication path; a spring element positioned to bias the valve member to open the fluid communication path; a valve chamber that communicates with the inlet and a valve seat; and a flow control member positioned in the valve chamber.