Abstract: A pressure modulated flow control valve, particularly adapted for water irrigation applications, comprises an unitary elastomeric pin defining a flow passage therethrough, a sub-chamber formed entirely in the pin and communicating with an inlet to the valve, and a flexible diaphragm separating the sub-chamber from the flow passage. In operation, the diaphragm is exposed to water pressure prevalent in the sub-chamber to flex into and vary the size of the flow passage to control and modulate the flow rate therethrough. The interchangeable pin is mounted in a housing of the control valve to effect a preselected near constant flow rate through the flow passage.

Abstract: A pressure modulated flow control valve, particularly adaptd for water irrigation applications, comprises an unitary elastomeric pin defining at least one flow passage therethrough and a flexible diaphragm overlying the flow passage, adjacent to an inlet to the valve. In operation, the diaphragm is exposed to water pressure prevalent at the inlet to the valve to flex into and vary the size of the passage to control and modulate the flow rate therethrough. In the preferred embodiment of this invention, the diaphragm will function to maintain a micro flow rate through the passage "near constant", e.g., selected from within the approximate overall maximum range of from 2.0 gph to 60.0 gph. The pin in interchangeable in a housing of the control valve to effect the desired near constant flow rate and is particularly adapted for use in pressure modulated drip-irrigation systems wherein water is communicated through the valve to a water distributing device, such as a sprayer or drip-type emitter.

Abstract: A micro flow control valve is interconnected between a main water line and a water distributing device, such as a mini sprayer. The interchangeable flow control valve is adapted to maintain a predetermined near constant micro flow rate of water to the distributing device within the approximate range of from 2.0 gph to 60.0 gph despite fluctuations in water pressure in the main water line. The control valve comprises a pin having at least one open-top channel defined at an outer surface thereof and a flexible diaphragm at least partially covering the channel. In operation, main line water pressure communicated to the control valve will function to flex the diaphragm into the channel to maintain such predetermined near constant micro flow rate in response to a variable pressure differential produced across the diaphragm.

Abstract: An irrigation emitter including a housing forming a chamber having diverging inlet and outlet walls, the diverging walls forming an apex which receives an end of an emitter plate therebetween; the emitter plate, when subject to pressure at the inlet wall below a predetermined low pressure occupying a position closing the inlet; the emitter plate, when subject to greater low pressure, forming momentarily with the outlet wall a flush flow outlet passage; the confronting surfaces of the outlet wall and emitter plate defining therebetween a drip flow passage. The emitter plate may be circular or rectangular and the portion of the chamber between the emitter plate and outlet wall may be enlarged to effect pressure reducing turbulent flow prior to discharge.

Abstract: A multiple emitter flow control which utilizes an irrigation flow tube provided with a series of outlets which receive a series of flexible emitters, the walls of each emitter being biased to form a flush flow passage extending radially inward from its corresponding outlet, the flush flow passage being collapsible, when the walls are subject to a bending force, causing the emitter to deflect angularly from its outlet, and also collapsible, when subject to water pressure above a preselected value, each emitter when collapsed by a bending force or by water pressure forming a drip flow passage from the interior of the irrigation tube through its outlet; the walls of the irrigation flow tube between irrigation cycles being biased to a normally flattened profile. An embodiment of the emitter being of greater length than the minor dimension of the flattened irrigation flow tube.

Abstract: A flush-drip irrigation emitter including a compact emitter element, a housing enclosing the emitter element and an insect guard, the emitter element having a pair of confronting oppositely arched flexible walls defining a flush flow passage with sharp lateral edges, one of the walls having at least one drip duct, the walls being responsive to a minimal pressure difference to collapse against each other in mutual sealing relation and confine flow to the drip duct.The housing including telescopable complementary housing components provided with an inlet connectable to a water supply and an outlet, the emitter element including sealing means interposed between the housing components, the housing components having mutually engageable latch elements and a tool receiving channel to effect separation; the outlet being arranged to receive directly or indirectly through a small irrigation tube, an insect guard.

Abstract: A continuous flow tube containing a series of emitters arranged to discharge through a wall of the flow tube, each emitter forming a flush flow passage collapsible to form a drip flow passage at a preselected low flow tube pressure; the emitters having side walls of such area with respect to the area of the flow tube, that when exposed transversely to initial flow through the flow tube the emitters form externally a series of flow restricting valves which rapidly raise the flow line pressure to a value at which drip flow occurs, thereby minimizing the number of emitters undergoing flush flow.One embodiment of the emitter is adapted to be installed by forcing the emitter into the flow tube from the exterior thereof. Another embodiment utilizes a flow tube initially in the form of a web which receives the emitters and is then rolled into a tube with the margins of the web circumferentially overlapped and bonded.