IL49067A - Trickle emitter - Google Patents

Description

The present Invention relates to a drip or trickle device of the type described 1n our earl ier Patent No 40838 .e. a construction wherein a sleeve having a groove 1n Its Inner face / Is fitted on a water conducting hose or pipe. The said groove Is in communication with the Interior of the water conduit on which the sleeve 1s set, water enters the groove which forms a lengthened conduit of hel ical , meandering or otherwi se labyrinth-wi se extension, the water being emitted at the end of the said lengthened conduit In the form of a slow trickle or dropwlse.

Practice has shown that with such emitters the emission Is not constant and uniform, varying with variations of pressure In the main and consequently 1n the water conducting hose which constitutes the feed line of the emitter.

It Is tfce object of the Invention to provide means which render the emission of water from such emitters quantitatively constant and uniform.

Accordingly there 1s provided a drip or trickle emitting device for use 1n Irrigation comprising a tubular sleeve having a groove 1n Its Inner face which groove extends spirally, meanderingly or In 1n the form of an Irregular maze, such sleeve being adapted to enclose a water conduit, an outlet from the conduit In the form of an aperture in Its wall being provided, an elastic membrane being Inserted 1n the said tubular sleeve and extending around the said water conduit, the membrane being perforated at at least one point, the said perforatlo n establ ishing communication - together with the said outlet from the conduit - between the Interior of the conduit and the groove.

The Invention will now be described with reference to the annexed drawings: In the drawings: Flg.l 1s a cross sectional view of a water conducting hose with the sleeve set thereon.

F1g.2 is a fractional , axial view of the arrangement of hose and emitter.

A hoee pipe 1 1 s enveloped - for part of its extension "by a foil 2.

The so enveloped conduit 1 1s enclosed in a tubul ar, slotted member 3, substantial ly as described In our Patent No. 40838.

The member 3, in the manner known 1s hel d tightly on conduit 1 by the rail 4 engaging and clamping together the flanges 5, as described In our previous patent mentioned above. In the Inner face of member 3 extends the groove (maze, or spiral , etc. )6.

An opening in the wal l of hose 1 , Indicated by numeral 7 permits water to exit from hose 1.

The hose 1 1s enveloped in a flexible, elastic membrane 8 which in turn has a hole 9.

The labrynthine groove 6 Is formed by a number of alternating ribs and depressions, as 1s wel l known. The ribs 1n front of outlet 7 (see F1g.2) are somewhat l ower than the other ribs .

Moreover, opposite the outlet 7 the ribs extend at a greater distance from one another forming a chamber 10.

Water flows in conduit 1 and 1s under full pressure of the main. When the water arrives at outlet 7, due to the pressure, after exiting of aperture 7 1t creeps along the outside of conduit 1 between the outside thereof and the foil - until 1t reaches hole 9, entering the groove 6 , travel l ing along 1t, to become eventually practically pressureless at the end of the groove, i .e. dripping or trickling outwardly, as 1s required.

The function of the enveloping membrane 1s as follows: The pressure from the main, prevail ing In con duit 1 , pushes the membrane from the hole 7, so that water enters the space PI to flow in the ring shaped space extending from PI to opening 9.

This can happen, due to the fact that the rib a (see F1g.2) opposite hole 7 s lower, permitting the membrane to bulge outwardly of hose 1. At the opening 9 the water enters the space P2 and creeps at the outside of the membrane into groove 6 to flow In the labyrinth, as 1s known, to finally drip from the emitter.

When a high pressure prevails 1n the conduit 1, the membrane 8 will be pressed closely to the rib a, fully sealing off the exit from space Pg. In that case pressure 1n space and space ?2 become equal, so that the Inherent elasticity of the membrane causes the latter to retract and thus permit again passage at rib a at a certain rate. In this way it 1s achieved that In spite of varying pressure substantially equal quantities of water per time unit will be emitted. Thus in spite of a tendency to deliver greater quantities at 7, the emission at the end of the maze will be substantially unchanged. With pressure dropping to normal, the bulge of the membrane at opening 7 will be smaller and the passage at the chamber P2 will be wider, permitting greater emission. After cessation of excess pressure, the membrane, due to Its elasticity, reverts to normal, the passage into the groove increasing.

Claims (4)

WHAT IS CLAIMED IS:

1. .. A drip or trickle emitter device for use in i rrigation comprising a tubul ar sleeve having a groove in its inner surfacC-which groove extends spirally, meanderingly or in the form of a maze, such sleeve being adapted to enclose a water conduit, an outlet from the conduit in the form of an aperture in its wall being provided, an elastic membrane being Inserted in the said tubul ar sleeve and extending around the said water conduit, the membrane being perforated at at least one point, the said perforation establishing communication - together with the said outlet from the conduit - between the interior of the conduit and the groove, said membrane bul ging outwardly under pressure and reverting to normal state due to its elasticity, thereby regularizing the rate of emission.

2. The drip or trickle emitter claimed in claim 1 , characterised thereby that the said maze is formed by alternating grooves and ribs In the Inner face of the sleeve and at least one rib opposite the outlet from the conduit 1s lower than other ribs.

3. The drip or trickle emitter as claimed in cl aim 2, characterised thereby that the distance between two ribs opposite the outlet from the conduit is greater than the di stances between other ribs .

4. The drip or trickle emitter, substantially as hereinbefore described with reference to and as ill ustrated in the accompanying drawl ngs . POB. 33116 TEL-AVIV, ISRAEL Attorneys for Appl icant