DRIP IRRIGATION EMITTER CONSTRUCTION

Abstract: A drip irrigation unit adapted to be assembled with a plurality of like units to define a plurality of emitters (8) connected in series includes, a tubular core section at one end (10), a tubular barrel section (20) at the opposite end for receiving the core section of another like unit and a tubular intermediate section (30) integrally joining the core section and the barrel section, the core section and/or the barrel section being formed with ribs (13) to produce a labyrinth passageway for conducting the water flow therethrough at a low rate when two like units are assembled together with the core section of one unit received in the barrel section of the other unit.

Description: DRIP IRRIGATION EMITTER CONSTRUCTION The present invention relates to an emitter construction for use in drip irrigation lines. Drip irrigation lines are generally produced by extruding the drip irrigation line with the emitter units integrally formed within the extruded line, or with outlet openings for attaching the emitter units to the extruded line. The extrusion equipment used is relatively expensive to install and to operate; also, the extruded lines are relatively bulky to handle and to store. In addition, the known emitters are generally used in irrigation systems supplied with water which has been pressurized by pumps. However, there are many areas of the world that could benefit from drip irrigation systems but which are lacking in pressure-boosting pumps and which therefore can supply the water only by gravity feed. An object to the present invention is to provide a drip irrigation emitter construction having advantages in one or both of the above respects . According to one aspect of the present invention, there is provided a drip irrigation unit adapted to be assembled with a plurality of like units to define a plurality of emitters connected in series, the drip irrigation unit 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 unit; and a tubular intermediate section integrally 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 between the surfaces for conducting the water flow therethrough at a low rate to the outer surface of the core section, when two like units are assenbled together with the core section of one unit received in the barrel section of the other unit. In one described embodiment, the surfaces of the core section and barrel section are both formed with axially-extending circumferentially-spaced ribs, the ribs of the core section alternating with the ribs of the barrel section such that all the ribs define a plurality of axially-extending passageways connected in series at their opposite ends to define the labyrinth passageway. A second embodiment is described wherein the outer surface of the core section is formed with a plurality of circumferentially-extending axially-spaced ribs defining the labyrinth passageway with the inner surface of the barrel section of another like unit. As will be described more fully below, drip irrigation emitters and lines may be constructed in accordance with the foregoing features by means of a plurality of modular units which can be produced in volume and at low cost, shipped and stored in a compact form, and conveniently assembled at the site to produce drip irrigation lines of various configurations and size. In addition, such drip irrigation lines can be used with low pressure water supply systems. Further features and advantages of the invention will be apparent from the description below. The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein: Fig. 1 illustrates one form of drip irrigation emitter system constructed in accordance with the present invention; Fig. 2 illustrates the construction of one drip irrigation line in the system of Fig. 1; Fig. 3 is a three-dimensional view illustrating the basic unit used, for making the drip irrigation line of Fig . 2 ; Fig. 4 illustrates a T-connector used in the drip irrigation line of Fig. 2; Fig. 5 illustrates the core section at one end of the basic unit of Fig. 3; Fig. 5a is a sectional long line 5a—5a of Fig. 5; Fig. 6 is a longitudinal sectional view illustrating the barrel section at the opposite end of the basic unit of Fig. 3; Fig. 6a is a sectional long line 6a—6a of Fig. 6; Fig. 7 is a three-dimentional view, with parts broken away, showing the core section of one basic unit received in the barrel section of the adjacent basic unit, and the manner they cooperate to produce a drip irrigation emitter; Fig. 7a is a sectional view along line VIIa--VIIa of Fig. 7, with the inlet and the outlet for the labyrinth in the respective emitter being shown in broken lines; Fig. 8 is a diagrammatic view illustrating the labyrinth in the construction of Fig. 7 including its inlet and outlet; Fig. 9 is a side elevational view, partly in section, of another basic unit constructed in accordance with the present invention; Fig. 9a is a transverse sectional view along line IXa—IXa of Fig. 9; Figs. 10 and 11 are three-dimensional views illustrating, respectively, the opposite ends of the drip irrigation unit of Fig. 9; Fig. 12 illustrates a plurality of the units of Fig. 9 in assembled condition; and Fig. 13 is a view similar to that of Fig. 9 but illustrating an additional drip irrigation unit which may be included in a drip irrigation line for providing intermediate water connections to such line. The drip irrigation system illustrated in Figs. 1-8 is particularly designed for low-pressure water supply sources, such as in gravity-fed water sources. Thus, Fig. 1 illustrates a water supply, diagrammatically shown at 2, for supplying water by gravity to a water distributor line 3 having a plurality of lateral lines 4, 5 connected to a plurality of drip irrigation lines 6 via T-connectors 7. Each line 6 includes a plurality of basic modular units assembled together to produce a plurality of drip irrigation emitters connected in series and having outlets, shown at 8, for discharging the water at a low rate. Each of the basic units 9 making up the drip irrigation line 6 is shown in Fig. 3. It includes a small-diameter core section 10 at one end, a larger-diameter barrel section 20 at the opposite end, and an intermediate section 30 integrally formed with the two end sections 10, 20. A plurality of the basic units 9 are assembled together to form the drip irrigation line 6 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. 7. The core section 10 includes an outer cylindrical portion 11 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 as shown in Figs. 7 and 8, there are six ribs 13; five ribs are of the same length, and one rib 13a is of longer length, e.g. by about 1 mm, for a purpose to be described below. The barrel section 20 at the opposite end of unit 9 is also formed with an outer cylindrical portion 21 and, inwardly thereof, 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 9 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 the barrel section 20, such that the two groups of ribs define a labyrinth consisting of a plurality of axially- extending passageways connected in series at their opposite ends, as shown in Fig. 8. The intermediate section 30 of each unit 9 is also of cylindrical configuration. It has an outer diameter such that its outer surface is flush with the outer surface of the external ribs 13 in the core section 10 and also flush with the inner surfaces of the inner ribs 23 in the barrel section 20. Thus, the juncture of the intermediate section 30 with the core section 10 defines a radial step 31 (Fig. 3), and the juncture of the intermediate section 30 with the barrel section 20 defines a second radial step 32. The end of the intermediate section 30 adjacent to the barrel section 20 is formed with a radial passageway 33 leading from the interior of the intermediate section to an axial passageway 34. The latter passageway leads through the radial step 32 to the interior of the barrel section 20 between a pair of is ribs 23. Passageways 33, 34 thus define an inlet into the labyrinth produced by the external ribs 13 of the core section 10 and the internal ribs 23 of the barrel section 20. As shown in Fig. 8, the elongated rib 13a of the core section 10 is at one side of the inlet 33 so as to steer the inletted water to one direction into the labyrinth defined by the two groups of ribs 13, 23, as shown in Fig. 8. The opposite end of the intermediate section 30 is formed with an elongated slot 35 extending axially from radial step 31 towards the opposite end of the intermediate section, i.e. towards its barrel section 20. Slot 35 is of a length slightly longer than the cylindrical portion 21 of the barrel section 20, such that when the core section 10 of one basic unit 9 is inserted into the barrel section 20 of another basic unit, the cylindrical portion 21 of the barrel section 20 leaves the end 35a of slot 35 uncovered. This uncovered portion 35a of the slot serves as an outlet from the labyrinth defined by the internal ribs 13 of the core section 10 and the internal ribs 23 of the barrel section 20. As shown particularly in Fig. 6, the end of barrel section 20 adjacent to the intermediate section 30 is formed with an annular shoulder 24 engageable with ribs 13 of the core section 10 of the basic unit 9 inserted into the barrel section. The respective end of the intermediate section 30 is also formed with an annular shoulder 36 engageable with the end of the cylindrical portion 11 of the inserted core section 10. The T-connector 7 includes a leg 41 (Fig. 4) for connection to the respective lateral line 4, 5, and two coaxial legs 42, 43, each for connection to one of the drip irrigation lines 6. The T-connector may be of the same construction as each of the basic units 9 illustrated in Fig. 3, with the addition of leg 41 for feeding the water from the respective lateral line 4, 5 into the interior of the two coaxial legs 42, 43. Thus, a plurality of the basic units 9 may be applied to each T-connector 7, with the barrel section 20 of one basic unit receiving the core section 10 of the adjacent basic unit, to produce a drip irrigation line 6 consisting of a plurality of emitters all connected in series. Leg 42 of the T-connector 7 may be constructed in the same manner as leg 43, namely to include a second core section 10, which would also permit a drip irrigation line 6 to be assembled on opposite sides of the respective lateral. A further alternative would be merely to close the end of leg 42, in which case a drip irrigation line could be assembled only on one side of the respective lateral. It will thus be seen that a drip irrigation line 6 can be assembled by merely connecting together a plurality of the basic units 9 in the manner shown in Fig. 7, namely by inserting the core section 10 of one unit into the barrel section 20 of the next adjacent unit. hen a plurality of such basic units are thus assembled, the external ribs 13 of the core section 10 become located coaxially with respect to, and alternating with, the internal ribs 23 of the barrel section 20, so as to define a labyrinth consisting of a plurality of axially-extending passageways connected in series at their opposite ends, as shown particularly in Fig. 7 and in the diagram of Fig. 8. Radial passageway 33 and axial passageway 34 in the intermediate section 30 serve as an inlet into the labyrinth. Elongated rib 13a of the core section steers the inletted water to one direction through the labyrinth defined by the two groups of ribs 13, 23, as shown in Fig. 8. The uncovered end 35a of slot 35 in the intermediate section 30 of the next unit serves as the outlet from the labyrinth. The basic units 9 can be produced in volume and at low cost, e.g. by injection molding. These units can be shipped and stored in a relatively compact form, and can be conveniently assembled at the site, by inserting the core section 10 of one unit into the barrel section 20 of the adjacent unit, to produce drip irrigation lines of any desired configuration and size. As one example, the basic unit 9 may be constructed according to the following dimensions: core section 10 of 40 mm, constituted of cylindrical portion 11 of 10 mm and ribbed portion 11 of 30 mm; intermediate section 30 of 100 mm; and barrel section 20 of 40 nun, constituted of ribbed portion 22 of 30 mm and unribbed portion 21 of 10 mm. The drip irrigation unit illustrated in Figs. 9-11 also includes a core section 110 at one end, a larger- diameter barrel section 120 at the opposite end, and an intermediate section 130 integrally formed with the other two sections. Fig. 12 illustrates how a plurality of the basic units shown in Fig. 9 may be assembled together to form a drip irrigation line, such as line 6 in Fig. 1, by inserting the core section 110 of one basic unit into the barrel section 120 of the adjacent basic unit. In this case, however, the labyrinth passageway is constituted of a plurality of interconnected circumferentially-extending passageways, rather than longitudinally-extending passageways, between the core section of one unit and the barrel section of another like unit. Thus, as shown in Figs. 9 and 10, the labyrinth passageway is defined by a longitudinally-extending rib 111, a first plurality of circumferentially-extending axially-spaced ribs 112, and a second plurality of circumferentially-extending axially-spaced ribs 113, all formed in core section 110. As shown particularly in Fig. 10, ribs 112 extend for substantially the complete circumference of the core section 110, being joined at one end to one side 111a of axial rib 110, and being spaced at the opposite end from side 111b of the axial rib to define a space 112a. Ribs 113 alternate with ribs 112, and similarly extend for substantially the complete circumference of the core section. In this case, however, each rib 113 is joined at one end to side 111b of axial rib 111, and is spaced at its opposite end from side 111a of the axial rib to define a space 113a. The outer diameter of all the ribs 111, 112 and 113 of core section 110 is egual to the inner diameter of the barrel section 120, so that when a core section of one unit is received within a barrel section of another like unit, the inner surface 121 of the barrel section 120 defines with the outer surface of ribs 111-113 of the core section 110 a labyrinth passageway in which the water flows circumferentially, but changes in direction each 360° (less the thickness of rib 111), to reduce the flow through the labyrinth passageway. As best seen in Fig. 10, the first rib 112 is spaced slightly inwardly of the end of the core section to define an unribbed portion 114 at the end of the core section. As shown in Fig. 9, the barrel section 120 is formed with an inner annular shoulder 122 at its juncture with the intermediate section 130. Shoulder 122 may be selectively engaged with, or disengaged from, the outer end of the unribbed portion 114 of another like unit core section 110 to permit flow through the respective emitter unit, or to block flow from the respective emitter unit. For releasably retaining the two units in the selected position, the intermediate section 130 of each unit is formed with an outwardly-projecting pin 131 adjacent to the ribs 111-113 of the core section 110; and the barrel section 120 is formed with two axially-spaced recesses or holes 123, 124, at the end of that section remote from the intermediate section 120, for selectively receiving pin 131. Thus, a plurality of the basic emitter units illustrated in Figs. 9-11 may be assembled together as shown in Fig. 12. If the respective emitter unit is to be operative, pin 131 of the respective emitter unit would be received within the outer opening 123 of the adjacent unit, as shown by emitter unit 100a in Fig. 12. In such case, the end of the unribbed portion 114 is spaced from the annular shoulder 122, permitting flow from the interior of the preceding unit to the outer surface of unribbed portion 114 and into space 112a (Fig. 10) between the end rib 112 and the axial rib 111. The water will then flow through the labyrinth passageway defined by the spaces between the ribs 112, 113, reversing each 360°, and will outlet through the space 112a between rib 112 and rib 111 at the opposite end of the labyrinth. On the other hand, if the particular emitter is to be disabled so as not to discharge any water, pin 131 of the core section of one unit would be received within the inner opening 124 of the other like unit, whereupon unribbed portion 114 of one unit would abut against annular shoulder 122 of the other unit, thereby blocking the flow to the inlet of the labyrinth, as shown by emitter unit 100b in Fig. 12. If the emitter units are to be assembled in long lines, it may be desirable to include one or more T-connector units as illustrated in Fig. 13 to permit connection to water sources at intermediate points of the line. Thus, the emitter unit illustrated in Fig. 13 is basically of the same construction as described above with respect to Figs. 9-12, except that it includes a T-connector 140 in its intermediate section 130 to permit connection to another water supply line if desired. While the invention has been described with respect to two preferred embodiments, it will be appreciated that these are set forth merely for purposes of example, and that many variations may be made. For example, the core section and the barrel section may be provided as separate members to be assembled together to define drip irrigation emitter units per se to be connected to a conventional water supply line. Many other variations, modi ications and applications of the invention may be made.

Claims: CLAIMS 1. A drip irrigation unit adapted to be assembled with a plurality of like units to define a plurality of emitters connected in series, said drip irrigation unit 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 unit; and a tubular intermediate section integrally 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 between said surfaces for conducting the water flow therethrough at a low rate to the outer surface of the core section, when two like units are assembled together with the core section of one unit received in the barrel section of the other unit. 2. The unit according to Claim 1, 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. 3. The unit according to Claim 2, 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. 4. The unit according to Claim 3, wherein said intermediate section of each unit includes, at one end, a first passageway defining the inlet to the labyrinth of one emitter, and a second passageway at the opposite end defining the outlet from the labyrinth of the next adjacent emitter of the series. 5. The unit according to Claim 1, wherein said outer surface of the core section is formed with a plurality of circumferentially-extending axially-spaced ribs defining said labyrinth passageway with the inner surface of the barrel section of another like unit. 6. The unit according to Claim 5, wherein said outer surface of the core section is further formed with an axially-extending rib joined to ends of said circumferentially-extending ribs to define a labyrinth having a passageway which changes in direction each 360° of water flow therethrough. 7. The unit according to Claim 6, wherein said circumferentially-extending ribs are constituted of a first plurality of ribs and a second plurality of ribs, the ribs of said first plurality being joined to one side of said axially-extending rib and spaced from the opposie side of said axially-extending rib; the ribs of said second plurality alternating with the ribs of said first plurality, being joined to said opposite side of the axially-extending rib, and being spaced from said one side of the axially- extending rib; the spaces between said axially-extending rib and said circumferentially-extending ribs at the opposite sides of said labyrinth serving as the inlet and outlet, respectively, of said labyrinth. 8. The unit according to Claim 7, wherein said barrel section defines an inner annular shoulder at its juncture with the intermediate section, and wherein the opposite ends of said unit are formed with cooperable retainer elements for selectively retaining the core section of one unit in either a flow-through position or a flow- blocking position with respect to said barrel section of another like unit. 9. The unit according to Claim 8, wherein said cooperable retainer elements include a projection formed in one of said emitter unit sections selectively receivable in one of two recesses in another like unit. 10. The unit according to Claim 9, wherein said projection is a pin formed in said intermediate section adjacent to said core section, and said two recesses are axially-spaced holes formed in said barrel section remote from said intermediate section. 11. A drip irrigation emitter, comprising: a tubular core member formed with a first group of axially-extending circumferentialy-spaced ribs on its outer surface ; a tubular barrel member formed with a second group of axially-extending circumferentially-spaced ribs on its inner face alternating with said ribs on the outer surface of the core member such that both groups of ribs define a plurality of axially-extending passageways connected in series at their opposite ends to define a labyrinth; said members being formed with an inlet leading from the interior of the core member to one end of said labyrinth, and with an outlet leading from the opposite end of said labyrinth to an external surface of one of said members . 12. The emitter according to Claim 11, wherein said core member includes an outer cylindrical portion, a ribbed portion inwardly thereof formed with said first group of ribs, and an inner cylindrical portion inwardly of said ribbed portion and having an outer surface flush with the outer surfaces of said first group of ribs; and wherein said barrel member includes an outer cylindrical portion having an inner diameter equal to the outer diameter of said inner cylindrical portion of the core member, and a ribbed portion inwardly of said cylindrical portion and formed with said second group of ribs alternating with said first group of ribs of the core member. 13. The emitter according to Claim 12, wherein said labyrinth outlet is through the external surface of said inner cylindrical portion of said core member and is not covered by said outer cylindrical portion of the barrel member . 14. The emitter according to Claim 13, wherein said core member and said barrel member are sections of the opposite ends of two like drip irrigation units; each of said two like units being further formed with an intermediate section between said core section and said barrel section and including at one end the labyrinth outlet of the respective emitter. 15. A drip irrigation emitter, comprising: a tubular core member having an outer surface of a predetermined diameter; and a tubular barrel member having an inner surface of substantially the same diameter as the outer surface of the tubular core member and enclosing said tubular core member; the outer surface of said tubular core member being formed with a plurality of ribs defining a labyrinth with said inner surface of the barrel member, said ribs comprising: an axially-extending rib; a first plurality of circumferentially-extending, axially-spaced ribs joined to one side of said axially- extending rib and spaced from the opposite side of said axially-extending rib; and a second plurality of circumferentially- extending axially-spaced ribs alternating with the ribs of said first plurality, said ribs of said second plurality being joined to said opposite side of said axially-extending rib and being spaced from said one side of the axially- extending rib; the spaces between said circumferentially- extending ribs and said axially-extending rib at the opposite ends of said labyrinth serving as the inlet and outlet, respectively, to the labyrinth. 16. The emitter according to Claim 15, wherein said barrel member and core member are formed with cooperable retainer elements for selectively retaining the core member in either a flow-through position or a flow- blocking position with respect to said barrel member. 17. The emitter according to Claim 16, wherein said cooperable retainer elements include a projection formed in one of said members selectively receivable in one of two recesses formed in the other of said members. 18. The emitter according to Claim 17, wherein said projection is a pin formed in said core member, and said two spaces are axially-spaced holes formed in said barrel member. 19. The emitter according to any one of Claims 15-18, wherein said core member and said barrel member are sections at the opposite ends of two like drip irrigation units . 20. A drip irrigation line including a plurality of drip irrigation units according to any one of Claims 1-19 assembled together to define a plurality of emitters connected in series. 21. A drip irrigation emitter according to any one of Claims 1-19 substantially as described with reference to and as illustrated in the accompanying drawings. 22. A drip irrigation line according to Claim 20, substantially as described with reference to and as illustrated in the accompanying drawings.

Inventors: ROSENBERG PERETZ, ROSENBERG, PERETZ
Applicants: ROSENBERG PERETZ, ROSENBERG, PERETZ
Application year: 1997
Main classification: B05B15
IPC codes: A01G25