WO1999020402A1

WO1999020402A1 - Drip irrigation devices and method of making same

Info

Publication number: WO1999020402A1
Application number: PCT/IL1998/000506
Authority: WO
Inventors: Peretz Rosenberg
Original assignee: Peretz Rosenberg
Priority date: 1997-10-19
Filing date: 1998-10-18
Publication date: 1999-04-29
Also published as: AU9558998A; IL121996A0

Abstract

A drip irrigation modular unit (2), adapted to be assembled in modular fashion with a plurality of like units (2), to define a plurality of emitters connected in series, includes a tubular core section (10) at one end having an outer surface of a predetermined diameter, a tubular barrel section (20) at the opposite end having an inner surface (21) of a diameter substantially the same as the outer surface of the core section (10) for receiving the core section (10) of another like device, and a tubular intermediate section (30) joining the core section (10) and the barrel section (20). The core section (10) and/or the barrel section (20) are formed with ribs (13, 23) to produce a labyrinth passageway for conducting the water at a low rate to the outer surface of the core section (10), when two like devices are assembled together. The three sections (10, 20, 30) are constituted of three separate parts with one end of the core section (10) and barrel section (20) each receiving one end of the tubular intermediate section (30).

Description

DRIP IRRIGATION DEVICES AND METHOD OF MAKING SAME

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to drip irrigation devices, and also to a method of making such devices. The invention is particularly directed to the drip irrigation modular unit described in my Patent Application PCT/IL97/00230, the description of which is hereby incorporated by reference.

My above-cited Patent Application PCT/IL97/00230 describes a drip irrigation modular unit adapted to be assembled in modular fashion with a plurality of like units to define a plurality of emitters connected in series, the drip irrigation device comprising: a tubular core section at one end having an outer surface of a predetermined diameter; a tubular barrel section at the opposite end having an inner surface of a diameter substantially the same as the outer surface of the core section for receiving the core section of another like device; and a tubular intermediate section joining the core section and the barrel section; at least one of the surfaces of the core section and barrel section being formed with ribs to produce a labyrinth passageway for conducting the water flow therethrough at a low rate to the outer surface of the core section, when two like devices are assembled together with the core section of one device received in the barrel section of the other device. Two embodiments were described: in one, the labyrinth passageway is defined by axially-extending circumferentially-spaced ribs; and in the other, the labyrinth passageway is defined by circumferentially- extending axially-spaced ribs. In both described embodiments, the core section, barrel section, and intermediate section, were all constructed as a single integral unit for assembly, in a modular fashion, with other like units to define a plurality of emitters connected in series .

BRIEF SUMMARY OF THE INVENTION

According to one aspect of the present invention, the core section, the barrel section, and the intermediate section are constituted of three separate parts with one end of said core section and said barrel section each receiving one end of the tubular intermediate section.

According to another aspect of the present invention, the core section and the barrel section are manufactured as separate parts; the intermediate section is manufactured as a continuously-extruded tube and is cut to desired length; the core section and barrel section are attached to the opposite ends of a cut length of the tube.

According to further features in the preferred embodiments described herein, the core section and barrel section are mechanically attached to the opposite ends of a cut length of the tube. These sections are each formed with a socket for the respective end of the cut tube, each of the sockets having an annular locking rib projecting from its inner surface and shaped to permit a cut length of tube to be forcefully inserted into the socket and to lock the tube against forceful withdrawal from the socket .

The present invention provides a number of important advantages over the construction and method described in the PCT application. Thus, the present invention enables the intermediate section to be manufactured as an extruded tube, and to be cut to size, as desired, according to the dripper spacings required for any particular application. In addition, the present invention simplifies the mold design as it enables the relatively complicated mold, required for producing the three integrally-formed sections, to be replaced by two relatively simple molds, for the core and barrel sections, respectively. Further, the present invention enables commonly-available extruded tubes to be used, thereby requiring storage and shipping only of the two end sections, permiting a substantial reduction in storage and shipping costs.

A further advantage in this construction over other known drip-irrigation devices is that the labyrinth passageway has a larger diameter than the tubular intermediate section, thereby providing a compact construction with a low sensitivity to clogging in the labyrinth passageway . BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:

Fig. 1 illustrates a section of a drip irrigation line, including a modular drip irrigation unit constructed in accordance with the present invention assembled with like modular units at its opposite ends;

Fig. 2 is an enlarged view, partly in section, illustrating one modular unit constructed in accordance with the present invention;

Fig. 3 is a fragmentary view illustrating the manner in which one modular unit is assembled with the next-adjacent modular unit to produce a labyrinth passageway for discharging the water at a low rate;

Fig. 4 is a sectional view along line IV- -IV of Fig. 3; and

Fig. 5 is a diagramatic view illustrating the labyrinth passageway;

DESCRIPTION OF A PREFERRED EMBODIMENT

The drip irrigation device illustrated in the drawings is basically of the same construction as the modular unit described in my above-cited Patent Application PCT/IL97/00230, the description of which is incorporated by reference. Such drip irrigation devices are particularly designed for low-pressure water supply sources, such as in gravity-feed water sources. The present invention is directed to another method of making the drip irrigation modular units described in that Patent Application, and also to slight modifications in the structure of such drip irrigation modular unit to enable them to be produced by the new method.

Fig. 1 illustrates a part of a drip irrigation line, generally designated 2, including a plurality of modular units 4 assembled together in a modular fashion to provide a plurality of dripper emitters connected in series for discharging the water at a low rate, as shown at 6. Each of the modular units 4 includes a core section 10 at one end, a barrel section 20 at the opposite end, and an intermediate tubular section 30 joined to the two end sections 10, 20. A plurality of the basic modular units 4 are assembled together to form the drip irrigation line 2 by inserting the core section 10 of one basic unit into the barrel section 20 of the adjacent basic unit, as shown for example in Fig . 3.

The core section 10 includes an outer cylindrical portion 11 (Fig. 2) and, inwardly thereof, a ribbed portion 12 of the same outer diameter as the cylindrical portion 11 but formed on its outer surface with a plurality of axially-extending circumferentialy-spaced ribs 13. In the illustrated example (see Figs. 4 and 5), there are six ribs 13: five ribs are of the same length, and one rib 13a is of slightly longer length, e.g. by about 1 mm, for a purpose to be described below.

The barrel section 20 at the opposite end of modular unit 4 is also formed with an outer cylindrical portion 21 and, inwardly thereof, with a ribbed portion 22. The cylindrical portion 21 has an inner diameter such as to engage the outer surfaces of ribs 13 when the core section 10 of another like unit 4 is inserted into it, as will be described below. The ribbed portion 22 is formed on its inner surface with a plurality of axially-extending circumferentialy-spaced ribs 23 adapted to be alternatingly received between ribs 13 of the core section 10 of another like unit when inserted into its barrel section 20. The arrangement is such that the two groups of ribs 13, 23 define a labyrinth consisting of a plurality of axially- extending passageways connected in series at their opposite ends, as shown in Figs. 4 and 5.

In the method described in the above-cited PCT application, the core section 10 and barrel section 20 are integrally formed, as by injection molding, together with the intermediate section 30. In the method of the present application, the core section 10 and barrel section 20 are formed as separate parts attachable to the opposite ends of the intermediate section 30. The intermediate section 30 may therefore be produced as a continuously-extruded tube and cut to the desired length. As shown in Fig. 2, the core section 10 includes an intermediate cylindrical portion 14 having an outer diameter equal to that of the outer edges of ribs 13. Core section 10 also includes an end cylindrical portion 15 of a larger outer diameter, substantially equal to the outer diameter of cylindrical portion 21 of the barrel section 20. Cylindrical portion 15 is formed with a socket 16 for receiving the respective end of tube 30. For this purpose, the inner surface of socket 16 includes an annular locking rib 17 having a tapered forward face 17a to permit the forceful insertion of the tube end into socket 16, and a perpendicular rear face 17b joined to face 17a by a sharp edge 17c adapted to bite into the outer surface of the inserted tube 30 and thereby to lock the tube against forceful withdrawal from the socket 16.

The inner cylindrical portion 11 of core section 10 is formed with an elongated slot 18 which serves as the inlet to the labyrinth defined by ribs 13 and 23. The intermediate cylindrical portion 14 is formed with another slot 19 which is only partially covered by the end cylindrical portion 21 of the barrel section 20 of the next adjacent modular unit 4 so as to serve as an outlet for the labyrinth passageway. Slot 19 extends from the radial step 14a between cylindrical portions 12, 14, and terminates just short of step 15a between cylindrical portions 14 and 15.

One end of the barrel section 20 of each modular unit 4 is similarly formed with a socket 26 for receiving the respective end of tube 30, and with an annular locking rib 27, corresponding to rib 17 in core section 10, to permit the forceful insertion of tube 30 into socket 26 and to lock the tube against forceful withdrawal from the socket. Socket 26 terminates in a radial step 28 at the inner edges of the ribs 23.

It will be seen that a modular drip irrigation unit 4 (Fig. 1 ) may be constructed by inserting one end of tube 30 into socket 16 of the core section 10, and the opposite end of tube 30 into socket 26 of the barrel section 20. It will also be seen that a plurality of such modular units 4 may be assembled together to form an irrigation line 2, by inserting end 11 of the core section 10 of one modular unit into end 21 of the barrel section 20 of the next adjacent modular unit until the elongated rib 13a in the core section of one modular unit abuts against radial step 28 in the barrel section 20 of the next adjacent modular unit, as shown in Fig. 3.

The two modular units are assembled in this manner such that the external ribs 13 of the core section 10 of one modular unit are located coaxially with respect to, and alternating with, the internal ribs 23 of the barrel section 20 of the next modular unit, thereby to define a labyrinth consisting of a plurality of axially-extending passageways connected in series at their opposite ends, as shown particularly in Fig. 4 and in the diagram of Fig. 5. Slot 18 in core section 10 serves as the inlet to the labyrinth. Elongated rib 13a of the core section, formed to one side of slot 18 and abutting against step 28, steers the inletted water to one side of the labyrinth defined by the two groups of ribs 13, 23, as shown in Fig. 5. Elongated rib 13a also spaces the ends of the remaining ribs 13 from step 28, while step 28 spaces the ends of ribs 23 from step 19a so as to produce the labyrinth passage shown in Fig. 5. The uncovered end of slot 19 in the core section serves as the outlet from the labyrinth.

It will thus be seen that the construction and operation of the illustrated drip irrigation devices are basically the same as described in the above-cited PCT application, incorporated herein by reference. The novel construction and method method, however provide the important advantages discussed earlier, particularly the advantage of enabling the use of an extruded tube which may be cut to size as desired according to the dripper spacer requirements for any particular application. Whereas the invention has been described herein with respect to a construction in which the labyrinth passageway is defined by axially-extending circumferentially-spaced ribs, the invention obviously could also be used in a construction wherein the labyrinth passagewy is defined by circumferentially-extending, axially-spaced ribs, or in a construction incorporated in a T-connector unit, such as also described in the above-cited PCT patent application. Accordingly, it will be appreciated that the preferred embodiment described herein is set forth merely for purposes of illustration, and that many other variations, modifications and applications of the invention may be made .

Claims

WHAT IS CLAIMED IS:

1. A drip irrigation modular unit adapted to be assembled in modular fashion with a plurality of like units to define a plurality of emitters connected in series, said drip irrigation device comprising: a tubular core section at one end having an outer surface of a predetermined diameter; a tubular barrel section at the opposite end having an inner surface of a diameter substantially the same as said outer surface of the core section for receiving the core section of another like device; and a tubular intermediate section joining said core section and said barrel section; at least one of said surfaces of the core section and barrel section being formed with ribs to produce a labyrinth passageway for conducting the water flow therethrough at a low rate to the outer surface of the core section, when two like devices are assembled together with the core section of one device received in the barrel section of the other device: characterized in that said core section, said barrel section, and said intermediate section are constituted of three separate parts with one end of said core section and said barrel section each receiving one end of the tubular intermediate section.

2. The modular unit according to Claim 1, wherein said core section and barrel section are each formed at one end with a socket for the respective end of the tubular intermediate section, each of said sockets having an annular locking rib projecting from its inner surface and shaped to permit the respective end of the tubular intermediate section to be forcefully inserted into the socket and to be locked therein against forceful withdrawal from the socket .

3. The modular unit according to either of Claims 1 or 2, wherein both of said surfaces of said core section and barrel section are formed with axially-extending circumferentially-spaced ribs, the ribs of the core section alternating with the ribs of the barrel section such that all said ribs define a plurality of axially-extending passageways connected in series at their opposite ends to define said labyrinth passageway.

4. The modular unit according to Claim 3, wherein said core section includes an outer cylindrical portion, a ribbed portion inwardly thereof formed with its said ribs, and an inner cylindrical portion inwardly of said ribbed portion and having an outer surface flush with the outer surface of its said ribs; and wherein said barrel section includes an outer cylindrical portion having an inner diameter equal to the outer diameter of said inner cylindrical portion of the core section, and a ribbed portion inwardly of said outer cylindrical portion and formed with its said ribs alternating with said ribs of said core section.

5. The modular unit according to either of Claims 1 or 2 wherein said core section is formed with the inlet to said labyrinth passageway and the outlet from said labyrinth passageway.

6. A drip irrigation emitter, comprising: a first member formed at one end with a tubular core section; and a second member formed at one end with a tubular barrel section receiving said core section of the first member; at least one of said sections being formed with ribs to produce a labyrinth passageway between the two sections for conducting water flow therethrough at a low rate; the opposite ends of said first and second members being formed with a socket for receiving the end of a tube supplying water to the emitter; each of said sockets having an annular locking rib projecting from its inner surface and shaped to permit a tube to be forcefully inserted into the socket but to lock the tube against forceful withdrawal from the socket.

7. The emitter according to Claim 6, wherein said core section is formed with the inlet to said labyrinth passageway and the outlet from said labyrinth passageway.

8. The emitter according to either of Claims 6 or 7, wherein both said core section and barrel section are formed with axially-extending circumferentially-spaced ribs, the ribs of the core section alternating with the ribs of the barrel section such that all said ribs define a plurality of axially-extending passageways connected in series at their opposite ends to define said labyrinth passageway .

9. The emitter according to Claim 8, wherein said core section includes an outer cylindrical portion, a ribbed portion inwardly thereof formed with its said ribs, and an inner cylindrical portion inwardly of said ribbed portion and having an outer surface flush with the outer surface of its said ribs; and wherein said barrel section includes an outer cylindrical portion having an inner diameter equal to the outer diameter of said inner cylindrical portion of the core section, and a ribbed portion inwardly of said outer cylindrical portion and formed with its said ribs alternating with said ribs of said core section.

10. A method of making a drip irrigation modular unit adapted to be assembled in modular fashion with a plurality of like units to define a plurality of emitters connected in series, said drip irrigation device comprising: a tubular core section at one end having an outer surface of a predetermined diameter; a tubular barrel section at the opposite end having an inner surface of a diameter substantially the same as said outer surface of the core section for receiving the core section of another like device; and a tubular intermediate section joining said core section and said barrel section; at least one of said surfaces of the core section and barrel section being formed with ribs to produce a labyrinth passageway for conducting the water flow therethrough at a low rate to the outer surface of the core section, when two like devices are assembled together with the core section of one device received in the barrel section of the other device: characterized in that said core section and said barrel section are manufactured as separate parts; in that said intermediate section is manufactured as a continuously-extruded tube and is cut to desired length; and in that said core section and barrel section are attached to the opposite ends of a cut length of said tube.

11. The method according to Claim 10, wherein said core section and barrel section are mechanically attached to said opposite ends of a cut length of said tube .

12. The method according to Claim 11, wherein said core section and barrel section are each formed with a socket for the respective end of the cut tube, each of said sockets having an annular locking rib projecting from its inner surface and shaped to permit a cut length of tube to be forcefully inserted into the socket but to lock the tube against forceful withdrawal from the socket.

13. The method according to Claim 10, wherein said core section is formed with the inlet to said labyrinth passageway and the outlet from said labyrinth passageway.

14. The method according to Claim 10 , wherein both of said surfaces of said core section and barrel section are formed with axially-extending circumferentially-spaced ribs, the ribs of the core section alternating with the ribs of the barrel section such that all said ribs define a plurality of axially-extending passageways connected in series at their opposite ends to define said labyrinth passageway.