GB2069652A - Multiple chamber drip irrigation hose - Google Patents

Abstract

A multiple chamber drip irrigation hose for distributing irrigation water and the like comprising, in combination, a primary (10) and at least one secondary (11) tube of flexible, water-impermeable material and joined at a common wall (16). Said common wall has a series of first holes (17) placing the interior of said primary tube in communication with the interior of said secondary tube. Said secondary tube has a series of second holes (18) leading from the interior of said secondary tube to the exterior. A flexible filamentary line (14) is positioned within said secondary tube to increase the turbulence of water flowing from the first holes to the second holes. The hose may be closed at its ends by clamps 12 or other means and connected to a source by tube 13. <IMAGE>

Description

SPECIFICATION Multiple chamber drip irrigation hose BACKGROUND OF THE INVENTION The invention set forth in this specification relates to new and improved drip or seep-type irrigation hoses.

In the past many different types of hoses or so-called emitters have been developed and utilized for the purpose of applying comparatively small amounts of water at various locations where such water is needed for agricultural-type purposes. Because such devices or structures apply only very limited or controlled amounts of water they are frequently referred to as drip or seep irrigation-type devices. It is not considered that an understanding of the present invention requires a detailed discussion of the various different types of hoses and emitters which have been proposed and utilized for this purpose.

BRIEF SUMMARY OF THE INVENTION An object of the present invention is to provide new and improved drip or seep-type irrigation hoses. More specifically the invention is intended to provide hoses of this type; which may be easily and conveniently produced at a comparatively nominal cost; which may be easily and conveniently installed using techniques such as have been previously used to install related hoses; which may be easily and conveniently employed for drip or seep irrigation purposes; which are capable of giving prolonged and reliable service; and which can be utilized so as to achieve effective utilization of water in growing plants.

In accordance with this invention these objectives are achieved by providing a multichamber drip irrigation hose for distributing irrigation water and the like in controlled amounts having a primary and at least one secondary tube of a flexible, water impermeable material joined along a common wall, said common wall having a series of first holes placing the interior of said primary tube in communication with the interior of said secondary tube, said secondary tube having a series of second holes leading from the interior of said secondary tube to the exterior of said hose in which the improvement comprises: a flexible, filamentary line positioned within said secondary tube and forming a restricted path for water flowing from one of said first holes to one of said second holes, said line being of a smaller dimension than said secondary tube so as to permit movement of said line radialiy in said secondary tube and having a plurality of deformations along its length for producing turbulerit flow in said secondary tube.

BRIEF DESCRIPTION OF THE DRAWINGS This apparatus is intended to be utilized in conveying and distributing irrigation water under pressure from a conventional conduit or source of such water as indicated in subsequent portions of this specification and as illustrated in the accompanying drawings in which Figure 1 is a side elevational view of a length of a presently preferred multiple chamber drop irrigation hose in accordance with this invention, this view being partly in section and indicating in a diagramatic manner the utilization of this hose; Figure 2 is a partial cross-sectional view of a length of a first alternate embodiment of the hose of the present invention; Figure 3 is a partial cross-sectional view of a length of a second alternate embodiment of the hose of the present invention;; Figure 4 is a partial cross-sectional view of a length of a third alternate embodiment of the hose of the present invention; Figure 5 is a cross-sectional view taken at line 5-5 of Fig. 2; Figure 6 is a cross-sectional view taken at line 6-6 of Fig. 3; Figure 7 is a cross-sectional view taken at line 7-7 of Fig. 4; Figure 8 is a partial side elevational view of an enlarged portion of the monofilament line 14 of Fig. 1; Figure 9 is a partial cross-sectional view of a length of a fourth alternate embodiment of the hose of the present invention; Figure 10 is a partial cross-sectional view taken at line 10-10 of Fig. 9; Figure 11 is a partial cross-sectional view taken at line 11-11 of Fig. 9; and Figure 12 is a partial cross-sectional view of a fifth alternate embodiment of the hose of the present invention.

From a consideration of the remainder of this specification and of the drawings it will be realized that the illustrated irrigation hose is not the present invention itself, but is a specific structure embodying the essential features or concepts of the present invention.

Such features or concepts are defined or summarized in the appended claims. They may be utilized within a number of structures which may differ significantly in appearance from one another.

DETAILED DESCRIPTION Illustrated in Figs. 1 and 8 is a hose 1 for distributing irrigation water and the like formed of flexible, water-impermeable material, such as a plasticized polyvinyl chloride, a common polyethylene or the like. The hose 1 is an integral unit consisting of a continuous length of such material. The hose 1 may be conveniently formed at a reasonable cost by conventional plastic extrusion techniques, or by sealing a continuous sheet of plastic film with heat and pressure or glue.

The hose 1 has a primary tube 10 and a secondary tube 11 of flexible, water-imperme able material joined at a common wall 16.

The common wall 1 6 has a series of first holes 1 7 placing the interior of the primary tube 10 in communication with the interior of secondary tube 11. The secondary tube 11 has a series of second holes 1 8 leading from the interior of the secondary tube 11 to the exterior. A flexible. filamentary line 14 of monofilament having a plurality of deformations 1 5 is positioned within the secondary tube 11 and forms a restricted path for water flowing from a first hole 1 7 to a second hole 18. This line 14 is of smaller dimension than the tube 11.

In normal use, the ends of the hose 1 are closed by conventional water-tight clamps 1 2 which seal both the primary and secondary tube. The interior of the primary tube 10 is connected to a source of pressurized irrigation water by a flexible tube 1 3. The ends of the hose 1 may be closed off by plugs, sealed by heat and pressure or other devices. Clamps 1 2 are preferred for convenience type reasons.

Figs. 2 and 5 refer to a first alternate embodiment of the present invention. The hose 2 has a primary tube 20 and a secondary tube 21. The primary tube 20 is joined to the secondary tube 21 by a common wall 25.

A plurality of uniformly spaced barriers 26 and 29 within the secondary tube 21 form a plurality of chambers Positioned within the secondary tube 21 is a monofilament line 24.

In this embodiment, the number of first and second holes preferably are equal. The number of either first or second holes plus one is preferably equal to the number of barriers, since the sealed ends serve as barriers at each end. Located in the common wall 25 is a series of first holes 27. Each first hole 27 is located adjacent one barrier 26. A series of second holes 28 is located in the secondary tube 21 adjacent the next barrier 29. The water flows through the primary tube 20 past a first hole 27 into the secondary tube 21 which forms a chamber and out a second hole 28. Optionally, a tertiary tube having chambers like those of the secondary tube may be employed.

Figs. 3 and 6 illustrate a second alternate embodiment of the hose 3. The hose 3 has a primary tube 30, a secondary tube 31 and a tertiary tube 32. Positioned within the secondary tube 31 is a first monofilament line 34.

Positioned within the tertiary tube 32 is a second monofilament !ine 33. The primary tube 30 is joined to the secondary tube 31 by a first common wail 35. The secondary tube 31 is joined to the tertiary tube 32 by a second common wall 36. Located in the first common wall 35 is a series of first holes 37 placing the interior of the primary tube 30 in communication with the interior of the secondary tube 31 Located in the second common wall 36 is a series of second holes 38 placing the interior of the secondary tube 31 in communication with the interior of the tertiary tube 32. Located in the tertiary tube 32 is a series of third holes 39 leading from the interior of the tertiary tube 32 of the exterior.

Figs. 4 and 7 illustrate a third alternate embodiment of the hose 4. The hose 4 has a primary tube 40 and two secondary tubes 41 joined to the primary tube 40 by a first common wall 45 and a second common wall 49. The first and second common walls 45 and 49 each have a series of first holes 47 placing the interior of the primary tube 40 in communication with the interior of each secondary tube 41. The secondary tubes 41 each have a series of second holes 48 leading from the interior of the secondary tube 41 to the exterior. A flexible, filamentary line 44 is positioned within each secondary tube 41 and forms a restricted path for water flowing from a first hole 47 to a second hole 48. This third embodiment is similar to the embodiment in Fig. 1, but having secondary tubes whereas Fig. 1 has a single secondary tube.

Figs. 9, 10 and 11 illustrate a fourth alternate embodiment of the hose 5. The hose 5 has a primary tube 50 and a secondary tube 51 joined to the primary tube by a common wall 55. The common wall 55 is reduced in thickness to allow the secondary tube to be more readily flattened or "oil-canned" when there is an increase in water pressure in the adjacent primary tube 50. Positioned within the secondary tube 51 is a monofilament line 54. Located in the common wall 55 is a series of first holes 57 placing the interior of the primary tube 50 in communication with the interior of the secondary tube 51. The secondary tube has a series of second holes 58 leading from the interior of the secondary tube 51 to the exterior.

Fig. 1 2 illustrates a fifth alternate embodiment of the hose 8. The hose 8 has the same structural features as hose 5 but the common wall 85 has a plurality of grooves 82 extending along the upper and lower surfaces to facilitate "oil-canning" or flattening of the secondary tube 81. Also shown are the primary tube 80 and the monofilament line 84.

The various figures of the drawings illustrate the structural relationships between the elements of the hose. The various elements are not all drawn to the same scale. For example, the various series of holes are all quite small and may not be clearly seen if drawn to scale. The secondary tube has also been enlarged to show the details of its construction. The filamentary line has been shown as a monofilament, although it may be either a multifilament or yarn.

When the pressure of the water supplied is sufficiently great, so long as that pressure does not exceed the rupture strength of the material, such pressure will tend to stretch the primary tube 10 so as to produce a crossorientation in a circular direction. This will overcome any orientation which may have resulted from the fabrication of the hose 1.

This action is considered to be beneficial in holding down manufacturing and material costs. The result is a hose which can withstand comparatively high pressure without rupture.

The series of first holes are non-restrictive and do not create a pressure drop between the primary tube and the secondary tube. The series of second holes may be either restrictive or non-restrictive. Both series of holes are preferably spaced from one another at periodic intervals such as about one every 60.96 cm to about one every 152.40 cm. The term holes includes a single circular opening, a plurality of circular openings, a single slot and a plurality of slots. The cross-sectional area of the second and third holes may or may not be uniform. The uniformity of the holes will aid in maintaining a uniform pressure gradient with water pressure of a given value. The holes may be created either by heat or mechanical action.

The flexible, filamentary lines which are positioned within secondary and tertiary tubes as indicated in the preceding discussion contain deformations such as the deformations 1 5 as indicated in the preceding so as to facilitate what may be referred to as "turbulence" flow in the water flowing from the first hole to the second and, when present, from the second hole to the third in any embodiment of an irrigation hose as described in the preceding. The term "turbulence" is not utilized in the preceding sentence in a technical, Reynold's number sense, but instead is used to indicate an irregular path or flow in which the velocity at a given point tends to vary irregularly and in which the nature of the flow is essentially of a nonuniform character.

Such turbulence is desirable because it aids in keeping any silt present in suspension. This in turn reduces the need for any significant degree of filtration of the irrigation water used with a hose as described. It is considered that particularly effective results in creating a desired degree of comparatively irregular or turbulent water flow can be achieved when deformations such as the deformation 1 5 are located about 0.64 centimeters (1 /4 of an inch) from one another along the length of flexible filamentary line as described.

It is, however, believed that such spacing is not significantly critical and that the presence of virtually and deformations reasonably near to one another will be satisfactory in creating a desired degree of turbulence. Indeed, any flexible filamentary line used may be a monofilament, a multifilament or any type of a twisted or braided line. Although monofilament lines are normally considered to have smooth exteriors it is considered that in practice due to manufacturing or other considerations such lines have enough surface irregularities so as to serve to tend to create a degree of turbulence as indicated in the preceding discussion. The flexible filamentary lines also enable one to more readily remove the apparatus from its original location by increasing its strength. The flexible lines also enable one to clear silt from the holes of the hose by pulling the lines back and forth.Generally the line is a fibrous material, such as a polyester, polyethylene or polypropylene, but the line may be copper wire which resists root intrusion.

Although it is possible to utilize the hose so that it is normally exposed to ambient air, it is considered preferable to bury the hose so that it is under the surface of the ground. The hose may be readily installed under the surface of the ground by dropping It in a ditch or unreeling it into a furrow behind a plow or similar structure being moved over a field.

One advantage of the present invention is the fact that the apparatus can be easily and cheaply removed from the field by pulling on one of its ends at the end of the growing season so that the field may be recultivated for use.

When the pressure compensating type multiple chamber drip irrigation hose is employed, an increase in water pressure in the primary tube causes a flattening or "oil-canning" in the adjacent secondary tube. The higher the pressure, the more the water passage in the secondary tube is reduced, providing for a constant water flow with varying pressure.

The flattening or "oil-canning" reduces the volume of the secondary tube, but due to the higher pressure the rate of water flow remains constant. The higher the water pressure in the primary tube, the greater the force causing the reduction in volume of the secondary tube as it flattens or "oil-cans" more and more.

When the water pressure in the primary tube returns to normal, the shape of the secondary tube returns to its former dimension which increases its volume allowing the water flow from the secondary tube to remain relatively constant. This expansion and contraction of the secondary tube has the effect of releasing particles from adhesion to the inner walls of the secondary tube, which would otherwise build up and block the tube. The undistorted cylindrical shape of the secondary tube has the greatest volume for a given amount of wall area. Any deviation from the cylindrical form will reduce the volume of the secondary tube. When one of the holes of the second series plugs up, there is an increase in pressure in the adjacent secondary tube which automatically blows out the obstruction.The full pressure blowout or flushing feature also occurs automatically each time the water is turned on, just before the common wall "oil cans or flattens into the compensating mode, due to the water pressure gradient as the full water pressure builds up.

It may be convenient in the manufacturing process to produce a hose of other than the precise shape or configuration illustrated. For example. the primary tube may be extruded so as to have an oval shape to facilitate its being taken up on a spool or the like. Such changes also facilitate storage and handling.

When a tube is formed in this manner, it will normally assume a circular cross-sectional configuration as significant pressure is applied to its interior.

The first alternate embodiment of the present invention allows for a relatively large pressure drop in a simple system by forcing the water to flow through an elongated chamber formed in the secondary tube. The series of first holes should be as close as possible to the left side of the barrier and the series of second holes should be as close as possible to the right side of the adjacent next barrier so as to form a path may of the maximum length within each chamber of the secondary tube.

The second alternative embodiment employing a primary, a secondary and a tertiary tube may be used to lengthen the run of the hose and to accommodate a higher water pressure.

It is contemplated that embodiments employiny higher orders than three levels of tubes are within the scope of this invention.

These higher level embodiments are merely an extension of the principles illustrated herein .

The third alternate embodiment of the present invention illustrates the use of two secondary tubes. More than two secondary tubes may be employed if so desired without departing from the scope of the present invention.

The embodiment illustrated in Fig. 1 would be half of that illustrated in Figs. 4 and 7. The secondary tubes may be placed in any relationship to one another which may be fabricated.

The fourth and fifth alternate embodiments of the present invention illustrate the use of the compensating multiple chamber drip irrigation hose. These embodiments are employed where a constant flow rate through the outlet is desired regardless of the pressure of the water supply. Thus, this type of hose may be used to go up and down hills while the flow rate remains constant. Such hoses may also be made in greater lengths than noncom pensatlnf ses since they are able to compensate fot a greater water pressure gradient.

The contperisdtirig type hose is produced by extruding rr, "airplane" web with either a ridge, a grouve or a filament in the fuselage.

The lower portion of the fuselage is either thinner than the upper portion or contains a plurality of grooves on both surfaces to allow the fuselage. which forms the secondary tube of the liose. to flatten or "oil-can" when the water pressure increases on its adjacent outer surface, which is the common wall. The hose is then slotted on both the lower and upper portions of the secondary tube or fuselage forming the holes of the first and second series. The wings are then folded over and sealed together to form the primary tube of the hose.

Alternately, the compensating type hose may be made by extruding a primary tube, placing the first series of holes in the primary tube, extruding a ribbon and placing the second series of holes on the ribbon, and gluing the ribbon over the first series of holes to form a secondary tube.

When the hose is constructed from a film,' the film usually ranges from about 0.01 cm to 0.02 cm in thickness. The film may be sealed with a conventional sealing wheel using heat.

and pressure, or the film may be glued.

When the hose is to be constructed with heavier walls, it is generally produced by extruding the plastic on conventional equipment. The walls of the extruded hose are generally greater than 0.036 cm in thickness.

The hose may be extruded in a finished form or as an "airplane" web which is subsequently sealed to form a hose. A typical multiple chamber drip irrigation hose has a primary tube of about 1.59 cm in diameter when fully distended by irrigation water at a pressure of about 1.05 kg per square cm. The interior of the secondary tube is about 0.10 cm in diameter. The series of first holes are non-restrictive and located at 152.40 cm intervals. The series of second holes are 0.04 cm in diameter, located at 152.40 cm intervals and are offset from the series of first holes. A monofilament line 0.04 cm in diameter is positioned within the secondary tube. At a water pressure of about 1.05 kg per square cm in the primary tube, each second hole will discharge about 3.79 liters of water per hour.A desirable rate of application of irrigation water for row crops is about 3.79 liters per 30.48 cm per row per day.

The rate of water flow may be changed by: Varying the water pressure entering the system, varying the cross-sectional area of the secondary tubes, varying the diameter of the flexible filamentary line, varying the surface treatment of the flexible filamentary line, ridge or groove, varying the spacing of the holes, varying the diameter of the varying pressure chamber in the compensating type hose, increasing the bulk of a muitifilament line, and by varying the length of the path of the fluid flow in the secondary tubes.

Although the irrigation hose is primarily designed for the dispensing of irrigation water, it is contemplated that systemic fertilizers, pesticides and/or herbicides may be admixed with irrigation water and applied at the same time. It is contemplated that due to the efficient application of water to the desired root zone with this hose that it may also be more economical to apply fertilizers, insecticides, pesticides and/or herbicides in this manner, since the materials are efficiently used as well as applied with a minimum amount of labor. Metering equipment such as that which may be employed in the application of the irrigation water can be used to control the amount of material applied.

Claims (11)

1. A multichamber drip irrigation hose for distributing irrigation water and the like in controlled amounts, comprising a primary and secondary tubes of a flexible water-impermeable material joined along a common wall, said common wall having a series of first holes communicating the interior of said primary tube with the interior of said secondary tube, and said secondary tube having a series of second holes leading from the interior of said secondary tube to the exterior of said hose, and a flexible, filamentary element accommodated within said secondary tube, said element being movable radially in said secondary tube and having a plurality of deformations along its length for producing turbulent flow in said secondary tube.

2. A hose according to claim 1 wherein: two secondary tubes are respectively joined to the primary tube by first and second common wall, said first and second common walls each having a series of first holes communicating the interior of said primary tube with the interior of the corresponding secondary tube, said secondary tubes each having a series of second holes leading from the interior of said secondary tube to the exterior; and a flexible, filamentary element having a plurality of deformations therealong is positioned within each of said secondary tubes and is movable radially in the respective tube.

3. A hose according to claim 1 or 2 including a tertiary tube of flexible, waterimpermeable material attached to the or one secondary tube at a common wall, further series of second holes extending through said second common wall, the tertiary tube having a series of third holes leading from the interior of said tertiary tube to the exterior, and a flexible, filamentary element positioned within said tertiary tube.

4. A hose according to any one of claims 1 to 3 wherein: the first holes are non-restrictive.

5. A hose according to claim 1 or 2 wherein: the second holes are non-restrictive.

6. A hose according to any one of claims 1 to 5 wherein the each element is a flexible monofilament line.

7. A hose according to any one of claims 1 to 6 wherein the or each said element is a flexible yarn positioned within said secondary tube.

8. A hose according to any one of claims 1 to 7 wherein: the first and second holes associated with the or each secondary tube have the same spacing, and the second holes are longitudinally offset from the first holes.

9. A hose according to any one of claims 1 to 8, including: a plurality of barriers within the or each secondary tube forming a plurality of chambers with each chamber communicating with a first hole and a second hole, the first hole being located adjacent the barrier at one end of the chamber and said second hole being located adjacent the barrier at the other end of the chamber.

10. A hose according to claim 9 wherein: said barriers are formed by sealing said secondary tube to itself.

11. A hose according to any one of claims 1 to 10, wherein the or each secondary tube has a circular cross section, said circular cross section being divided into approximately equal upper and lower portions said lower portion of the secondary tube forming said common wali and being thinner than said upper portion of said secondary tube wherein an increase in water pressure in the primary tube tends to flatten the adjacent secondary tube and reduce its volume for maintaining substantially the same rate of water flow from the hose due to the increased water pressure.

1 2. A multichamber drip irrigation hose substantially as herein described with reference to the accompanying drawings.