Abstract

Fluid flow control devices are described particularly useful as drip irrigation emitters provided with flow regulation to reduce their pressure-sensitivity, thereby enabling them to be used in long lines and in undulating terrain. The disclosed devices include a first flexible plastic strip bonded on one surface to a second plastic strip along bond lines defining a pressure-dropping passageway. A third plastic surface is bonded to the opposite surface of the first flexible plastic strip along bond lines defining therewith a static pressure chamber in which the first flexible plastic serves as a common wall with the chamber and the passageway for at least part of the length of the passageway. Thus variations in the velocity of the fluid through the pressure-dropping passageway causes the common wall to be flexed to vary the cross-sectional area of the passageway and thereby to regulate the fluid flow therethrough. Both linear-source emitters and point-source emitters are described.