Abstract:
An irrigation apparatus comprises an in-line dripper insert having a support for attaching a micro tube to the dripper outlet. A fluid conduit in which the insert is placed has an aperture in line with the support. The support may comprise a projection for securing a micro tube thereto, a sleeve for securing a micro tube or a connector thereto, or a shoulder for supporting the attachment of a connector to the fluid conduit at the aperture. The dripper insert is secured to the inner surface of the fluid conduit and is contained entirely therein. After detachment of the micro tubes, the main fluid line may be easily reeled or otherwise handled. The internal dripper provides structural internal support to the main fluid conduit when external pressure is applied to the line, such as when a micro tube or a connector is forced against the fluid line to be connected thereto.

Description:
TECHNICAL FIELD  
         [0001]    The present invention relates generally to irrigation apparatus having lateral lines, and more particularly, to inserts adapted to be contained within a fluid conduit for supporting directly a lateral tube extending from the conduit.  
         DESCRIPTION OF RELATED ART  
         [0002]    The present application is preferably used in a drip irrigation system. An irrigation system applies water to specific plant or root zone locations in controlled quantities. It is thereby possible to irrigate planted areas with substantially less water than is used by general broadcast sprinkler or flooding methods. Several apparatuses for use in irrigation systems are well known.  
           [0003]    One type of drip emitter, called a clipon dripper, is shown in U.S. Pat. Reg. No. 4,036,435, issued on Jul. 19, 1977, to Pecaro. The clipon dripper is generally large in size. Another type of a clipon dripper is the button dripper, which is typically smaller in size and is widely used in today&#39;s market. Both types of drippers include a connector attached externally to a main fluid conduit and a micro tube attachment facility. This apparatus has several disadvantages. The main fluid conduit cannot be easily reeled after attachment of the external dripper and the attachment of the external dripper is labor intensive which substantially increases the cost of the dripline. The button dripper, due to its size, has typically smaller fluid flow passageways and therefore is more sensitive to clogging. All external drippers have the disadvantage that the main fluid conduit may collapse or give way when external pressure is applied to attach the external dripper connector thereto. In addition, the external dripper connector may become dislodged when internal pressure is applied to the main fluid conduit.  
           [0004]    A second type of drip apparatus, called merely a connector, is shown in U.S. Pat. Reg. No. 5,692,858, issued on Dec. 2, 1997, to Vaughan. This apparatus comprises a micro tube attached to a connector, wherein the connector is attached directly to a main fluid conduit at an aperture therein. This apparatus also has several disadvantages. The connector may easily become dislodged from the main fluid conduit, i.e., “pop off” the fluid line, when fluid in the conduit is pressurized. Leakage may occur between the connector and the main fluid conduit if the conduit is moved or distorted, which may occur under pressurized fluid conditions.  
           [0005]    A third type of drip apparatus comprises an external connector secured to the main fluid conduit by an external clip or band. The connector and the clip or band may be manufactured as a single unit. This apparatus has several disadvantages. The apparatus may be expensive to install due to the expense of purchasing the clips and the connectors, and due to the labor costs of attaching each of the connectors and clips to the main fluid conduit. Moreover, the clip or band does not always hold the connector in watertight engagement with the main fluid conduit so that leaks may occur.  
           [0006]    There thus remains a need for an emitter apparatus that is easy to install, that is relatively inexpensive to purchase and manufacture, and that allows a main fluid conduit to be reeled and re-reeled after use. Moreover, there remains a need for an emitter apparatus that provides support to the main fluid conduit when connectors and/or micro tubes are secured thereto.  
         SUMMARY OF THE INVENTION  
         [0007]    These features are provided in the present invention by an irrigation apparatus comprising an insert, such as an in-line drip emitter, adapted to be secured within a main fluid conduit for supporting a lateral tube element, such as a micro tube or connector.  
           [0008]    In general, the invention provides an irrigation apparatus comprising an insert that is adapted to be received within a fluid conduit and having an outer surface mountable in physical contact with an inner surface of the fluid conduit. The insert includes a support adapted for supporting a lateral tube element extending through an aperture in the fluid conduit when the support is positioned adjacent to the aperture. The insert also includes a fluid passageway extending between the interior of the fluid conduit and the aperture.  
           [0009]    The insert in the preferred embodiment of the invention is an in-line drip emitter or dripper. It also may simply be a support element providing a relatively unrestricted water passageway between the interior of the fluid conduit and the aperture. The flow-limiting fluid passageway characteristic of drip emitters is not required for the invention. Further, the present invention can be applied to a variety of in-line drippers. For example, the internal micro tubing connector of the present invention can be implemented with a conventional non-compensated dripper or with a pressure compensated dripper. The dripper may have different features, such as a retention (non-leakage) valve, pressure regulating features or other such valve means. The physical configuration of the insert may also vary. For example, the insert may be cylindrical or flat in shape. It can be symmetrical, i.e., the output connector may be positioned centrally along the connector, or the insert may be asymmetrical, with the outlet positioned closer to one end of the insert.  
           [0010]    The invention also provides a method of assembling an irrigation apparatus. Generally, this method includes the steps of (1) providing an irrigation fluid conduit including an inner surface; (2) securing an insert to the inner surface of the fluid conduit; (3) forming an aperture in the fluid conduit adjacent to the insert; (4) extending an end of a tube element through the aperture; and (5) supporting the end of the tube element extending through the aperture relative to the insert.  
           [0011]    The preferred embodiment of the invention is thus seen particularly to provide an improved method and apparatus for connecting a micro tube to a drip irrigation line at the dripper location. The method and apparatus take advantage of the in-line dripper with all its advantages over the complicated, external button and strap/band drippers, and over the delicate prior art connector apparatus. Some embodiments of the present invention do not require additional connectors and adapters and reduces labor costs because once the fluid conduit is unreeled the only remaining task is to attach a micro tube to the output opening of the dripper. Moreover, the internal emitter provides structural support for the main fluid conduit when external pressure is applied to the conduit during attachment of a micro tube or a connector thereto.  
           [0012]    In a preferred embodiment the internal emitter comprises a cylindrical dripper having a flow-restricting fluid passageway formed between the dripper and the inner surface of the fluid conduit. The fluid passageway or labyrinth communicates between the interior of the fluid conduit and a tube-element support in a connection region on the dripper. The support is aligned with an aperture in the fluid conduit and facilitates connection of a lateral tube element relative to the internal dripper. The lateral tube element may be any device associated with a micro tube, such as an end of the tube or a connector to which a micro tube may be attached. The support may comprise a projection for securing a micro tube thereto, a sleeve for securing a micro tube therein, a sleeve for securing a connector thereto, or a shoulder supporting the fluid conduit around the aperture. The internal dripper typically is secured to the inner surface of the main fluid conduit and is contained entirely therein such that there are no projections outside the conduit. This is the preferred embodiment since, after detachment of the micro tubes, the main fluid line is free of external parts that could interfere with the reeling or other handling of the conduit. The internal dripper provides structural internal support to the fluid conduit when external pressure is applied to the line, such as when a micro tube or a connector is forced against the main fluid line to be connected thereto. The invention may also be practiced with embodiments that have a protrusion through the conduit aperture. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a partial cut-away top view of an internal emitter made according to the present invention.  
         [0014]    [0014]FIG. 2 is a partial cut-away bottom view of the internal emitter of FIG. 1.  
         [0015]    [0015]FIG. 3 is a side cross-sectional view taken along line  3 - 3  of FIG. 1.  
         [0016]    [0016]FIG. 3A is a view similar to that shown in FIG. 3 but additionally showing a micro tube connected to the internal emitter.  
         [0017]    [0017]FIG. 4 is an end cross-sectional view taken along line  4 - 4  of FIG. 3.  
         [0018]    [0018]FIG. 5 is a side cross-sectional view similar to that shown in FIG. 3 but showing a different connection device.  
         [0019]    [0019]FIG. 5A is a partial side cross-sectional view similar to that shown in FIG. 5 but showing a connector attached to the conduit at the internal emitter.  
         [0020]    [0020]FIG. 5B is a top view of the device shown in FIG. 5.  
         [0021]    [0021]FIG. 6 is a side cross-sectional view similar to that shown in FIG. 3 but showing a different conduit opening.  
         [0022]    [0022]FIG. 6A is a top view of the device shown in FIG. 6.  
         [0023]    [0023]FIG. 7 is a side cross-sectional view similar to that shown in FIG. 6 but showing a connector attached to the internal emitter with a micro tube attached thereto.  
         [0024]    [0024]FIG. 8 is a side view of a connector.  
         [0025]    [0025]FIG. 9 is a side cross-sectional view of a relatively flat internal emitter taken along line  9 - 9  of FIG. 10.  
         [0026]    [0026]FIG. 10 is a top view of the internal emitter of FIG. 9.  
         [0027]    [0027]FIG. 11 is a side cross-sectional view of an internal support element insert made according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0028]    Referring now to the figures, FIG. 1 is a partial cut-away top view of an irrigation apparatus  20  made according to the present invention. Apparatus  20  is formed by an outer member or sleeve  50  of a main fluid conduit  52  and a tubular insert  60 . The insert is also called an internal emitter, internal dripper, irrigation apparatus, or a dripper body. Sleeve  50  includes an opening  30  (shown in FIG. 3) through which a micro tube can be connected. The opening, or aperture, extends through the conduit from the hollow interior to an exterior surface thereof. As will be described in more detail below, sleeve  50  and insert  60  define a fluid passageway  22  that terminates at opening  30 . In another embodiment, insert  60  may singularly define a fluid passageway  22  that terminates at opening  30 , thereby forming a standalone emitter apparatus  20 .  
         [0029]    Main fluid conduit  52  and insert  60  typically are manufactured of high density, durable plastic so as to withstand high fluid pressures and harsh environmental conditions. The conduit and the internal emitter may be manufactured in any size or material as is desirable for particular applications. Preferably, insert  60  is inserted as the conduit is extruded using well-known drip irrigation line manufacturing methods. During this process, the insert is integrally bonded to the conduit.  
         [0030]    Insert  60  has an inner surface  61  (more clearly shown in FIG. 3) that defines, at least in part, an inner chamber  62  that preferably provides an uninterrupted fluid flow through an internal fluid passageway of conduit  52 . A series of inlet openings shown generally at  64  provide communication between the inner surface of chamber  62  and an inlet end  24  of fluid passageway or labyrinth  22 . Labyrinth  22  defines a fluid flow path extending between insert  60  and sleeve  50 , in a direction generally to the left in FIG. 1, so as to provide fluid flow at a channel  34 , formed in a support  28 , for support and connection of a micro tube, such as micro tube  70  shown in FIG. 3A. Labyrinth  22  may include pressure regulating means, as described in U.S. Pat. Reg. No. 5,111,996, issued on May 12, 1992 to Eckstein, and U.S. Pat. Reg. No. 5,615,838, issued Apr. 1, 1997 to Eckstein et al., wherein the disclosures of said patents are incorporated by reference herein.  
         [0031]    It will be appreciated that opening  30  in conduit  52  is aligned with support  28  of insert  60 . Accordingly, during manufacture of the conduit, it is preferable to insert all of the inserts in the same orientation and direction. This will standardize the position of the support, and thereby the opening, on the same side of the conduit and at regular intervals along the conduit.  
         [0032]    [0032]FIG. 2 is a partial cut-away bottom view of the internal emitter insert  60  of FIG. 1. In this bottom view labyrinth  22  is shown extending from the topside of the insert via intermediate channel  66 . Fluid flow through the labyrinth continues toward the right in FIG. 2 to outlet end  26 . From outlet end  26  fluid flows through channel  27  (shown in FIG. 3) and then through channel  34  (FIG. 1). Accordingly, a portion of the flow through conduit  52  flows into labyrinth  22  and then into micro tube  70 , and the remainder of the fluid continues to flow through conduit  52 .  
         [0033]    [0033]FIG. 3 is a side cross-sectional view taken along line  3 - 3  of FIG. 1. Support  28  includes a recess  32  and a stem  36 , positioned within the recess  32 .  
         [0034]    [0034]FIG. 3A is a view similar to that shown in FIG. 3 but additionally shows the end of micro tube  70 , also called a drip tube, connected to the internal emitter and forming, in combination, an irrigation apparatus  20   a . In particular, micro tube  70  is frictionally secured to stem  36  by placement of an end of the micro tube, also referred to as a tube element, through opening  30  in conduit  52  and into the recess  32 , also called a cavity, surrounding stem  36 , also called a projection. Due to the watertight seal between sleeve  50  and insert  60  around a perimeter of opening  30 , tube  70  need only be secured to stem  36  to provide a water tight seal between insert  60  and tube  70 . In other words, opening  30  may have a diameter greater than an outer diameter of tube  70  so that there is a slight gap  38  between the outer surface of the micro tube and the inner edge of opening  30 . This slight gap provides for ease of placement of tube  70  into recess  32  and positioning of the tube about stem  36 . Moreover, gap  38  allows for bending and flexing of the tube relative to conduit  52 . Stem  36  may, but preferably does not extend outwardly from conduit  52  so that the conduit, when the micro tubes are disconnected, may be reeled and unreeled without difficulty. Recess  32  and/or stem  36  preferably are aligned with and positioned inwardly of aperture  30  in the conduit.  
         [0035]    [0035]FIG. 4 is a cross-sectional view taken along line  4 - 4  of FIG. 3. Labyrinth  22  is shown in communication with outlet end  26 , which end is in communication with channel  27 . Channel  27  in turn is in communication with channel  34 . Opening  30  is shown having a diameter slightly smaller than a diameter of recess  32  but larger than an outer diameter of a tube adapted to be secured to stem  36 , as shown in FIG. 3A.  
         [0036]    [0036]FIG. 5 is a side cross-sectional view similar to that shown in FIG. 3 but showing a different conduit opening and support  28   a  of an irrigation apparatus  20   b . In this embodiment, fluid flows through channel  27 , through a connecting path  34   a  and into a reservoir  32   a . Opening  30   a  in sleeve  50  has a diameter approximately the same size as, or larger than, the diameter of reservoir  32   a  such that a micro tube can be frictionally received within opening  30   a  and reservoir  32   a . Opening  30   a  may be tapered so as to receive a mating tapered connector, such as connector  80   a  shown in FIG. 5A, wherein a micro drip tube is secured to the connector. Micro tube  70  typically is resilient and the outer walls of the tube frictionally engage the inner sidewalls  33  of reservoir  32   a  without collapsing or being substantially deformed, as shown in dashed lines in FIG. 5. Since there is no pressure within the micro tube during fluid flow, the micro tube holds against the sidewalls of reservoir  32   a.    
         [0037]    [0037]FIG. 5A is a partial side cross-sectional view similar to that shown in FIG. 5 but showing a connector  80   a  attached to the conduit at internal emitter  60   a , forming in combination an irrigation apparatus  20   c . In this embodiment connector  80   a  may be secured to conduit  52  at opening  30   a  by an external strap or band (not shown) as known in the art. The connector includes a tapered or inclined lower surface  42  such that the strap or band will pull the inclined surface into contact with opening  30   a  so as to create a watertight seal. The connector may also comprise a lower base portion  41 , shown in dashed lines, sized to be frictionally received within reservoir  32   a . Connector  80   a  includes an upper portion  40  adapted for attaching a micro tube thereto, as known in the art. Insert  60  is preferably attached to conduit  52  around the aperture. Accordingly, the insert acts to support the walls of conduit  52  when the connector or a micro tube is secured thereto such that the conduit will not collapse or deform under such external pressure.  
         [0038]    [0038]FIG. 5B is a top view of the device shown in FIG. 5. In this view reservoir  32   a  is shown in communication with channel  34   a.    
         [0039]    [0039]FIG. 6 is a side cross-sectional view similar to that shown in FIG. 3 of an irrigation apparatus  20   d  but showing a different conduit opening  30   b . In this embodiment, conduit opening  30   b  in sleeve  50  is smaller in size so as to receive a standard connector (shown in FIG. 8) within opening  30   b  and reservoir  32   a . Also, insert  60   a  has a support  28   a  that is the same as in the embodiment of FIG. 5. In particular, conduit opening  30   b  has a diameter smaller than a diameter of reservoir  32   a . The portion  66  of insert  60   a  forming recess  33  in contact with conduit  52  is also referred to as a shoulder. Shoulder  66  supports conduit  52  when connector  80  is inserted through aperture  30   b.    
         [0040]    [0040]FIG. 6A is a top view of the device shown in FIG. 6 wherein the opening  30   b  is shown aligned with reservoir  32   a.    
         [0041]    [0041]FIG. 7 is a side cross-sectional view similar to that shown in FIG. 6 but showing a connector  80  attached to the conduit  52  and with a micro tube  70  secured thereto. In this embodiment, forming in combination an irrigation apparatus  20   e , connector  80  is shown attached to opening  30   b  wherein a lower portion  44  of the connector also referred to as a tube element, is received within reservoir  32   a . Connector  80  with micro tube  70  attached thereto is known in the art. Accordingly, the internal emitter of the present invention can be utilized with connectors and micro tubes currently available so as to decrease retrofit costs to consumers. Moreover, due to the pressure regulating properties of labyrinth  22 , connector  80  will not readily be displaced from conduit  52  under pressurized fluid conditions within inner chamber  62  of the main fluid conduit, as occurs in the prior art. Additionally, insert  60   a , and in particular, shoulder  66  provides structural support for the internal surface  61  of conduit  52  as the connector is inserted into opening  30   b . In this embodiment, support  28   a  includes shoulder  66 . Attachment of connector  80  to the conduit, therefore, may be accomplished more readily than in prior art devices, thereby saving time and labor costs.  
         [0042]    As has been discussed, FIG. 8 is a side view of a connector  80  including an internal fluid passageway  46  extending there through, as known in the art.  
         [0043]    [0043]FIG. 9 is a side cross-sectional view of a relatively flat internal emitter  60   b  that is bonded to the inner surface  61  of sleeve  50  to form an irrigation apparatus  20   f . As with the previous embodiments, apparatus  20   f  is formed by inserting emitter  60   b  while conduit  52  is being extruded.  
         [0044]    The internal emitter includes a series of inlet openings shown generally at  64   a  that provide communication between chamber  62  and inlet end  24   a  of labyrinth  22   a . The labyrinth extends from inlet  24   a  to outlet  26   b , at the right end of internal emitter  60   b . From outlet end  26   b  of the labyrinth, fluid flows to intermediate reservoir  29 , and then through channel  27   b  that is connected to channel  34   b  as shown. Channel  34   b  extends upwardly through stem  36   b  positioned within recess  32   b . Recess  32   b  is aligned with opening  30   c  in conduit  52  for placement of a micro tube as described with reference to the embodiments previously described. As mentioned above, stem  36   b  typically does not extend outwardly into or through opening  30   c , i.e., the support  28   b  is positioned inwardly of aperture  30   c . The stem is adapted to frictionally receive a micro tube thereon.  
         [0045]    [0045]FIG. 10 is a top view of the internal emitter of FIG. 9 showing labyrinth  22   a  extending from left to right in the figure, and around recess  32   b.    
         [0046]    [0046]FIG. 11 is a side sectional-view of an internal support element insert  60   c  that is bonded to the inner surface of sleeve  50  to form an irrigation apparatus  20   g.    
         [0047]    The internal support element includes an inlet opening shown generally at  64   b  that provides communication between chamber  62  and channel  34   c . Channel  34   c  extends upwardly through stem  36   c  positioned within recess  32   c . Recess  32   c  is aligned with opening  30   d  in conduit  52  for placement of a micro tube. Stem  36   c  is adapted to frictionally receive a micro tube thereon, however, the support  28   c  can have different designs as shown for example in support  28   a  in FIG. 5 to receive a micro tube and hold it by means of friction to the outer side wall of the micro tube.  
         [0048]    The figures discussed above typically show only a portion of a fluid line, i.e., a single sleeve portion and a single insert. However, those skilled in the art will understand that multiple inserts may be placed within a continuous line of fluid conduit. It will also be understood that although the inserts described above form drip emitters, inserts may be used that do not form drip emitters. Further, an insert may have a plurality of supports for attaching a plurality of lateral tubes. Additionally, the internal dripper preferably is contained entirely within the conduit such that there are no projections outside the conduit. The invention may also be practiced with embodiments that have a protrusion through the conduit aperture.  
         [0049]    In the above description numerous details have been set forth in order to provide a more through understanding of the present invention. It will be obvious, however, to one skilled in the art that the present invention may be practiced using other equivalent designs.