IL122058A - Inlet means for drip irrigation water emitter - Google Patents

Abstract

A drip irrigation emitter (10) insertably attached to the inside face of a water supply pipe (12), the emitter having a housing (14) containing an inlet chamber (16) and an outlet chamber (18) connected by a flow control means (20), characterized by filtering means comprising a plurality of fins (22) projecting from said housing in communication with the interior of said water supply pipe, said plurality of fins being aligned linearly and extending parallel to the longitudinal axis of said water supply pipe, wherein each pair of said plurality of fins form a passageway (28) therebetween, allowing for unimpeded through flow of water between said plurality of fins and admitting free water flowing from the passageway at its full length to the interior of the supply pipe and vice versa. 3067 י' בטבת התשס" ד - January 4, 2004

Description

INLET MEANS FOR DRIP IRRIGATION WATER EMITTER ηΐΌ9Ίϋη ΠΊί7ϋ]Π TQD ΏΊΏ U7197 ΠΌ"Ό ^ΏΗ Eitan, Pearl Latzer, Cohen-Zedek P-1364-IL FIELD OF THE INVENTION This present invention relates to drip irrigation and in particular is directed to a system for continuous cleansing of the drip emitters within the pipe.

BACKGROUND OF THE INVENTION There are numerous types of emitters known in the art used for drip irrigation. All the emitter units comprise at least an inlet chamber in communication with the pressurized water within an irrigation pipe, pressure reducing means and an outlet chamber. The pressure of water entering the inlet chamber is reduced by pressure reducing means before entering the outlet chamber and thence exiting at lower pressure via a small outlet opening.

Drip level irrigation emitters are particularly sensitive to variations in pressure within the water supply pipe and to blockage of the outlet opening due to dirt, grit or other detritus. Various control mechanisms have been proposed for controlling fluctuations in pressure. For example, US Patent No. 4,209,133 to Mehoudar describes the use of a flexible membrane separating inlet and outlet control chambers. However, any blockage in the outlet aperture causes a rise of pressure in the outlet chamber. The increased pressure will cause the membrane to move and may thus dislodge the blockage. However, the cause of the blockage remains within the outlet chamber and may block the outlet aperture again. Furthermore, such control mechanisms do not prevent the grit and dirt from entering the inlet chamber and the emitter unit. 1 1364-IL Alternatively, in order to prevent the small outlet aperture from blocking, a filter unit is commonly placed in front of the inlet chamber.

US Patent No. 5,634,594 to Cohen describes a flow control device for use in a drip irrigation emitter which includes a plurality of inlet openings communicating with the pressurized fluid which are formed at tone end adjacent to the inlet. When a clogging particle enters the inlet openings the flow is reduced so that the differential pressure on opposite sides of a membrane, overlying the openings, cause the membrane to curve and increase the opening permitting the particle to flushed through the opening into the device. The offending particle, though dislodged, is not thrown out but remains within the system. 2 1364-IL SUMMARY OF THE INVENTION It is an objective of this invention to provide an improved emitter for drip irrigation systems.

It is a further objective of the invention to provide an emitter which provides filtering means to prevent clogging particles from entering the emitter.

There is thus provided, in accordance with an embodiment of the invention, a drip irrigation emitter for attaching to a water supply pipe. The emitter, which includes a housing containing an inlet chamber and an outlet chamber connected by a flow control means, is characterized by filtering means which include a plurality of fins projecting from the housing. The plurality of fins, which are in communication with the interior of the water supply pipe, are aligned linearly and extend parallel to the longitudinal axis of the water supply pipe. The passageways which are formed between the fins allows for unimpeded through flow of water between the fins.

Furthermore, in accordance with an embodiment of the invention, the emitter is insertably attached to the inside face of the water supply pipe. In an alternative embodiment, the emitter is externally attached to a water supply pipe.

Furthermore, in accordance with an embodiment of the invention, the cross-sectional shape of the fins may comprise any shape including trapezoidal, rectangular and semi-circular shapes. The wider base of the trapezoidal cross-section is proximate to the inlet chamber.

Additionally, in accordance with an embodiment of the invention, the emitter housing is a longitudinal or cylindrical. 3 1364-IL Furthermore, in accordance with an embodiment of the invention, the flow control means includes a meandering labyrinth. In addition, the flow control means further includes a pressure sensitive membrane.

Furthermore, in accordance with an embodiment of the invention, the emitter the drip irrigation emitter is manufactured from thermoplastic material. 4 I364-IL BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the appended drawings in which: Fig. 1 is an isometric view of an integral emitter unit constructed and operative in accordance with a preferred embodiment of the present invention; Fig. 2A is a plan view from below of the unit of Fig. 1 ; Fig. 2B is a side view of the unit shown in Fig. 2; Fig. 3 is a longitudinal view of the unit shown in Fig. 2; Fig. 4 is a cross sectional view of the unit shown in Fig. 2 taken along the lines IV-IV; Fig. 5 is a side view of the unit of Fig. 1 shown fitted to the inside of a pipe; Fig. 6 is an isometric view of the unit of Fig. 1 shown fitted to the inside of a pipe (shown in cut-off); Fig. 7 is an isometric view of an cylindrical shaped emitter unit, constructed and operative in accordance with another preferred embodiment of the present invention; Fig. 8 is a side view of the cylindrical shaped emitter unit of Fig. 7; Fig. 9 is a cross-sectional view of the cylindrical shaped emitter unit of Fig. 7, taken along lines IX-IX; Fig. 10 is an isometric view of an cylindrical shaped emitter unit, constructed and operative in accordance with another preferred embodiment of the present invention; 5 1364-IL Fig. 10 is an isometric view of an cylindrical shaped emitter unit, constructed and operative in accordance with another preferred embodiment of the present invention; Fig. 11 is a longitudinal sectional view of an cylindrical shaped emitter unit of Fig. 10; and Fig. 12 is cross-sectional view of the cylindrical shaped emitter unit of Fig. 11 , taken along lines XII-XII. 6 1364-IL DETAILED DESCRIPTION OF THE PRESENT INVENTION Reference is made to Figs. 1 - 6, which illustrate an integral emitter unit, generally designated 10, constructed and operative in accordance with a preferred embodiment of the present invention, Emitter unit 10, which is suitably bonded or attached to the inside face of a water supply pipe 12, comprises a generally longitudinal housing 14 having an inlet chamber 16 and an outlet pool 18 connected by means a flow reducing channel 20.

It is a feature of the invention that the inlet chamber 16 comprises a plurality of fins 22 which project from the housing 14 and are in communication with the interior of the water supply pipe 12. The plurality of fins 22 have a generally trapezoidal cross-section (best seen in Fig. 4) with the wider cone base being proximate to inlet chamber 16. Fins 22 are aligned linearly, extending parallel to the longitudinal axis of housing 14 and are separated from each other so as to provide passageways, referenced 28, between the fins 22. The passageways 28 allow the flow of water (the direction of flow is indicated by arrow 25) within the pipe 12 to be unhindered.

Since the fins have a trapezoidal cross-section with the wider gap 28 projecting into the water flow, clogging objects are initially trapped between the fins 22 and prevented from entering the inlet opening 16. Furthermore, since the passageways 28 between the fins 22 do not impede the flow, the relatively fast water flow rushing past and through the protruding fins 22 will tend to constantly flush and clear these trapped objects. Thus, the fins 22 act as a filtering means preventing relatively small objects from clogging the inlet chamber 16. Water 7 I364-IL entering the inlet chamber 16 will thus be relatively clear of detritus which could block the inlet chamber 16 and/or the flow reducing channel 20.

Flow reducing channel 20 acts to reduce and regulate the flow of water from inlet chamber 16 to outlet pool 18. Channel 20 may be constructed in any suitable manner, such as by means of a zigzag meandering labyrinth illustrated, so as to effectively reduce the water flow.

An outlet aperture 26, which is in communication with outlet pool 18, is formed in the wall of water supply pipe 12.

After entering the inlet chamber 16, the flow of water is reduced by channel 20 before entering outlet pool 18. The water exits to pipe 12 via outlet aperture 26.

Preferably, the emitter unit is manufactured from thermoplastic material, such as polyethylene.

It will be appreciated by persons knowledgeable in the art that the present invention is not limited to fins or ribs having a trapezoidal cross-section, but may have any suitable cross-section such as rectangular or semi-circular, for example.

Reference is now made to Figs. 7 - 9 which illustrate a cylindrical shaped emitter unit, generally designated 200, constructed and operative in accordance with another preferred embodiment of the present invention.

Fig. 7 is an isometric view of cylindrical shaped emitter unit 200, Fig. 8 is a side view and Fig. 9 is a cross-sectional view of the cylindrical shaped emitter unit 200. 8 1364-IL In the embodiment of Figs. 7 - 9, cylindrical shaped emitter unit 200 comprises a sleeve member 202 which is insertable within a water supply pipe (not shown). The outer face of the sleeve 202 comprises a labyrinth type passageway 204 connected to an outlet chamber 206.

Cylindrical emitter unit 200 further comprises an inlet chamber 203 connected to labyrinth 204. A plurality of protruding ribs 208 which project from the inner face of the sleeve 202 adjacent to the inlet chamber into the flow of the water within the water supply pipe.

Fins 208 are aligned linearly, extending generally parallel to the longitudinal axis of the water supply pipe. Preferably, the fins 208 extend over at least half the perimeter of the pipe. The fins 208 may be shaped to any suitable cross-section such as trapezoidal, as described hereinabove with respect to the embodiment of Figs. 1-6.

Fins 208 are aligned linearly, extending parallel to the longitudinal axis of the water supply pipe. Fins 208 are separated from each other so as to provide passageways, referenced 210, between the fins 208. The passageways 210 allow the water within the water supply pipe to flow unhindered.

Similarly, to the embodiment described hereinabove with respect to Figs. 1- 6, the fins 208 act to initially trap objects which could block the inlet chamber of the emitter 200. The flow of water rushing past the protruding fins 208 will tend to flush and clear any trapped objects from time to time.

Water flowing through the pipe having a cylindrical emitter unit 200 fitted will pass through the plurality of ribs 208, entering the inlet chamber 203. The flow of water is then reduced by the labyrinth passageway 204 before entering the 9 1364-IL outlet chamber 206. Finally, the water drips out of the pipe via suitably formed low-pressure outlets formed in the pipe (not shown).

Reference is now made to Figs. 10 - 12 which illustrate a cylindrical shaped emitter unit, generally designated 300, constructed and operative in accordance with another preferred embodiment of the present invention.

Fig. 10 is an isometric view of the cylindrical shaped emitter unit, Fig. 11 is a longitudinal sectional view and Fig. 12 is cross-sectional view of the cylindrical shaped emitter unit 300.

Cylindrical emitter unit 300 is generally similar to cylindrical emitter unit 200 described hereinabove with respect to Figs. 7 - 8. Elements of this embodiment of the invention which are similar to elements which have been previously described with respect to the preferred embodiment hereinabove, are similarly designated and will not be further described.

Cylindrical emitter unit 300 comprises a cylindrical sleeve member 302 which is insertable within a water supply pipe (not shown). The outer face of the sleeve 302 comprises a labyrinth type passageway 306 connected via to an outlet chamber 308.

Cylindrical emitter unit 300 further comprises an inlet chamber 310, a flexible membrane 312 and a cover member 314 covering one face of membrane 312. A plurality of protruding fins 318 project from the inner face of the sleeve 302 adjacent to the inlet chamber 310 into the water flowing within the pipe.

Similar to the previously described embodiments hereinabove, fins 318 are aligned linearly, extending generally parallel to the longitudinal axis 320 of the 10 1364-IL water pipe (See Fig. 11). The fins 318 may be shaped to any suitable cross-section, such as trapezoidal.

Fins 318 are separated from each other providing passageways, referenced 322, between the fins 318. The passageways 322 allow the water within the pipe to flow unhindered.

Similarly, to the embodiments described hereinabove, the fins 318 act to initially trap objects which could block the emitter 300. The flow of water rushing past the protruding fins 318 will tend to flush away trapped objects.

The cylindrical emitter unit 300 is similar to known in the art units and will not be described in detail. Briefly, the operation of the cylindrical emitter unit 300 can be described as follows: Water flowing through the pipe passes over and through the plurality of fins 318, and a portion of the water enters inlet chamber 310. The flow of water then flows via a first circumferential channel 330 (Fig. 12) into the labyrinth passageway 306. On exiting the labyrinth passageway 306, the water continues via a second circumferential channel 332, passageway 334, orifice 336 and then over the membrane of 312. The water then flows through opening 309 into channel 307 an finally into outlet chamber 308. From outlet chamber 308, the water drips out of the pipe via the low-pressure outlet apertures (not shown) formed in the pipe.

Membrane 312 is similar to membranes commonly use in emitters and act as pressure deformable members to control the pressure difference between inlet and outlet chambers, 310 and 308 respectively. Increase in the differential pressure deforms the membrane 312 pushing it up against the opening 309, 1 1 1364-IL thereby reducing the flow through the emitter. The differential pressure then decreases and consequently, the membrane 312 returns to its original position (best seen in Fig. 11).

It will be appreciated that the present invention is not limited by what has been described hereinabove and that numerous modifications, all of which fall within the scope of the present invention, exist. For example, the present invention is not limited to internal fitted irrigation emitters but may also be used with externally attached emitters. Rather the scope of the invention is defined by the claims which follow: 12 1364-IL

Claims (11)

1. A drip irrigation emitter, insertably attached to the inside face of a it

2. A drip irrigation emitter according to claim 1 wherein the cross- sectional shape of said plurality of fins comprises one of a group including trapezoidal, rectangular and semi-circular.

3. A drip irrigation emitter according to claim 2 wherein the wider base of said trapezoidal cross-section is proximate to said inlet chamber.

4. A drip irrigation emitter according to any of the previous claims and wherein said housing is a longitudinal.

5. A drip irrigation emitter according to any of claims 1- 3 and wherein said housing is a cylindrical. 13 1364-IL 122058/4

6. A drip irrigation emitter according to any of the previous claims wherein said flow control means comprises a meandering labyrinth.

7. A drip irrigation emitter according to claim 6 and wherein said flow control means further comprises a pressure sensitive membrane.

8. A drip irrigation emitter according to any of the previous claims wherein said emitter unit is manufactured from thermoplastic material.

9. A drip irrigation emitter according to claim 1 wherein said emitter is externally attached to a water supply pipe.

10. Apparatus according to any of claims 1 - 9 substantially as described hereinabove.

11. Apparatus according to any of claims 1 - 9 substantially as illustrated in any of the drawings. Law Offices of A. & Co. P-1364-IL 14 1364-IL