Patent Description:
Irrigation systems deliver liquid comprising water, often containing plant nutrients, pesticides and/or medications, to plants via networks of irrigation pipes.

Relative thin walled irrigation pipes, sometimes called tapes, may be used for irrigation, for example when the irrigation pipes are used for short durations of time, such as a single season and then possibly disposed.

During installment or use, the irrigation pipes may be exposed to wear and tear that may cause damage to the pipes in particular in cases where the irrigation pipe has a relative thin wall.

Irrigation pipes may deliver liquid to plants via emitters or drippers that are installed on or integrated inside the irrigation pipes. Such emitters may be heat bonded to the pipe to form a so-called drip irrigation pipe or dripper pipe.

In some cases such dripper pipes may be susceptible to damage at the areas of bonding and/or areas of connection to the drip emitter.

<CIT> describes a drip irrigation hose formed with a plurality of outlets for discharging the water at longitudinally-spaced locations along the length of the hose includes a plurality of emitter elements secured to the hose at longitudinally-spaced locations along its length to define a plurality of turbulent flow passageways each in communication with the interior of the hose for discharging water from a hose outlet at a slow rate. Each of the turbulent flow passageways is defined by a relatively elastic first material co-extruded with a relatively inelastic second material both bonded to the hose with the relatively elastic material being pressure-deformable, as compared to the relatively inelastic material, to change the turbulent flow passageway of each emitter element in response to the pressure of the water in the hose at the respective emitter element.

<CIT> describes a drip irrigation apparatus including a main water flow channel having associated therewith along a length thereof a plurality of pressure-controlled drip irrigation emitter units and at least one secondary water flow channel extending generally parallel to the main water flow channel and receiving water from at least one of the plurality of pressure-controlled drip irrigation emitter units, the at least one secondary water flow channel having water outlets disposed along the length of the main water flow channel, intermediate the plurality of pressure-controlled drip irrigation emitter units.

<CIT> describes a subsurface drip irrigation device having a tube having a first layer having a releasable herbicide compounded in the first layer are on an inside surface of the first layer, a second barrier layer adjacent the first layer, outlets extending through the tube in a spaced relationship along the tube, drippers positioned on an inside surface of the tube in a spaced relationship over an outlet where the barrier layer prevents outward movement of released herbicide through the first layer and directs the released herbicide into a flow path through the tube for exiting the drip irrigation device through an inlet into the dripper and out the outlet in the tube for preventing root intrusion into the device.

The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. Advantageous features are defined by the dependent claims.

In an embodiment, there is provided an irrigation pipe extending along an axis and comprising a pipe wall, wherein the pipe wall comprises a base portion and a plurality of bulge members extending away from the base portion. The bulge members may be ribbed shaped, possible extending along the pipe axis upon inner and/or outer faces of the pipe wall.

In an embodiment, the base portion may have a substantial constant thickness and each bulge member increases thickness of the pipe wall at the location where it is formed, preferably in a radial direction (inwards or outwards) when the pipe is held in a general cylindrical state.

Such increase in wall thickness may be defined as occurring "locally" where the bulge is formed, while at locations absent of bulges, pipe material may be absent between adjacent bulges in a peripheral direction, thus forming valleys, possibly axially extending valleys between adjacent bulges. Such valleys may have relatively large lateral extensions when placed between bulges that a far apart in a peripheral direction.

In an embodiment, for a pipe having a base portion thickness T less than about <NUM> millimeters (<NUM> mil), at least some of the bulge members may have a height that extends radially away from the base portion up to about <NUM> millimeters (<NUM> mil) minus T. Choice of height for a bulge member may be in order to 'as if' "upgrade" wall thickness of a pipe (at least locally where ribs/bulges are formed). Thus, bulge/rib height may be chosen to at least locally increase wall thickness of a <NUM> mil pipe to a <NUM> mil, <NUM> mil pipe category and so on.

In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the figures and by study of the following detailed descriptions.

It is intended that the embodiments and figures disclosed herein are to be considered illustrative, rather than restrictive. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying figures, in which:.

Further, where considered appropriate, reference numerals may be repeated within the figures to indicate like elements.

Attention is first drawn to <FIG> illustrating each an embodiment of an irrigation pipe <NUM>, <NUM>, <NUM>. Each one of the pipes extends along an axis X and is formed thereabout.

The embodiment of pipe <NUM> in <FIG> is illustrated including a pipe wall having a peripheral base portion <NUM> of substantial contact thickness T (see thickness T illustrated in <FIG>) and a plurality of axially extending bulge members <NUM> here in the form of elongated rib-like structures that extend above the base portion in an outer radial direction when the pipe is held generally cylindrical. The members <NUM> are here optionally formed about axis X, preferably extending each generally parallel to axis X. In an embodiment (not shown), the bulge members <NUM> may be formed helically about axis X or any other suitable configuration.

The embodiment of pipe <NUM> in <FIG> is illustrated including a plurality of axially extending bulge members <NUM> generally similar to those of pipe <NUM>. Pipe <NUM> is here seen also including additional bulge members <NUM>, here two such members, formed on base portion <NUM>, which have a larger cross sectional area than members <NUM> in a cross section perpendicular to axis X.

The bulge members <NUM> are here also shown possibly extending continuously along an outer face of the pipe each having an elongated rib-like structure and formed about axis X, preferably extending each generally parallel to axis X. In addition, adjacent bulge members <NUM> as shown here may have a larger circumferential spacing therebetween about axis X than the members <NUM>. In an embodiment (not shown), the bulge members <NUM> may be formed helically about axis X or any other suitable configuration.

With attention drawn to <FIG> an embodiment of a pipe <NUM> is shown including possibly only bulge members <NUM> generally similar to those seen in <FIG>. Here only two such bulge members <NUM> are shown and the remaining outer face of the wall's base portion <NUM> is shown possibly devoid of bulging structures that are formed thereon.

Pipe embodiments that may not be shown, however come within the scope of the present disclosure, should be understood to include various combinations of bulge members generally similar to those discussed herein, e.g. bulge members <NUM>, <NUM> or those discussed below in <FIG> and <FIG>.

At least some of the suitable pipes including bulge members as discussed herein may be relative thin walled pipes, sometimes called 'tapes'. Such a thin walled pipe structure may be characterized by a wall thickness (at locations not including a bulge) that may range from about <NUM> (<NUM> mil) to about <NUM> millimeters (<NUM> mil) (measured in a radial direction on a pipe held in a cylindrical state).

Such relative thin wall thickness may render the pipes relative weak to wear and tear that may occur during use in an irrigation application and thus susceptible to damage. Therefore, in such thin walled pipes the bulge members may serve to strengthen the pipe wall and increase its resistance and robustness to damage during use e.g. when laid in a field for irrigation purposes.

Pipes including bulge members as discussed herein may however not necessarily be only of a relative thin walled type, but may be of also larger wall thickness. In such relative larger wall thickness pipe (as also in thin walled pipes), the bulge members may serve as deposits of pipe material for strengthening certain areas of the pipe that may be susceptible to damage.

Such areas of the pipe susceptible to damage may include a lower side of the pipe exposed to a ground face when laid in a field, or a side of the pipe exposed to friction from machinery used for laying the pipes in the field (etc.). In one example, such bulges may also strengthen locations of the pipe where other devices may be mounted.

Attention is drawn to <FIG> showing a cross sectional view taken in a plane perpendicular to axis X of a pipe generally similar to the above discussed pipes. In this example, the cross section is taken on pipe <NUM> showing its bulge members <NUM> being circumferentially spaced apart about axis X.

Attention is drawn to <FIG> showing a cross sectional view taken in a plane perpendicular to axis X of a pipe generally similar to the herein discussed pipes. In this example, the cross section is taken on pipe <NUM> showing its bulge members <NUM> being circumferentially spaced apart about axis X. In addition, in this view the pipe is shown including a device, here a drip emitter <NUM>, mounted to its inner side.

In an aspect of the present disclosure, bulge members positioned above a location where the drip emitter is mounted to the pipe may be useful in providing additional protection to this area, which may be susceptible to damage. As an example, a drip pipe may be installed in a field by directing the pipe through a framework of an agricultural machine (not shown) towards the ground face. During process, such as this, areas of the pipe that include devices within them, such as a drip emitter, may form bumps in the pipe e.g. when the pipe is flattened, which may in turn increase friction against the framework of the agricultural machine.

Consequently, an embodiment a drip pipe (as illustrated in <FIG>) may include at least one bulge member located between opposing lateral sides <NUM> of the drip emitter. In the shown example, bulge member <NUM> is shown located between the lateral sides <NUM> however other rib members such as those described herein may be used for protecting the drip pipe. In the shown example three such bulge members <NUM> are illustrated located between sides <NUM>, however fewer than three (such as one) or more than three bulge members may be placed between the sides <NUM> of the drip emitter.

Attention is drawn to <FIG> showing various types of bulge member configurations that may be used, where these cross-sectional views represent either an irrigation pipe without any device (e.g. drip emitter) mounted thereto or a cross sectional view taken axially in-between adjacent devices (such as drip emitters) at a location where the device is absent.

In <FIG> pipe embodiments are shown including bulge members on the outer side of the wall's base portion <NUM>, which appear generally similar to the bulge member <NUM> shown in <FIG> and <FIG>. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having the same material of the pipe; and on the right hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having a different material to that of the pipe.

In <FIG> pipe embodiments are shown including bulge members on the inner side of the wall's base portion. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having the same material of the pipe; and on the right hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having a different material to that of the pipe.

In <FIG> pipe embodiments are shown including bulge members on both the inner and outer sides of wall's base portion. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having the same material of the pipe; and on the right hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members illustrated as possibly having a different material to that of the pipe.

In <FIG> pipe embodiments are shown including bulge members on the inner side of the wall's base portion, here formed as strips having a relative large circumferential extension. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including such bulge member or strip having a circumferential extension extending along an arc of about <NUM> degrees. On the right hand side of <FIG>, a pipe embodiment <NUM> is shown including such bulge member or strip having a larger circumferential extension possibly formed on the full inner circumference of the pipe.

In <FIG> pipe embodiments are shown having strip-like structures generally similar to those in <FIG> with additional bulge members possibly similar to bulge <NUM> mounted on-top of the strips. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members formed on a strip generally similar to that on the left hand side of <FIG>. On the right hand side of <FIG>, a pipe embodiment <NUM> is shown including bulge members formed on a strip generally similar to that on the right hand side of <FIG>.

In <FIG> pipe embodiments are shown including both inner and outer bulge members. On the left hand side of <FIG>, a pipe embodiment <NUM> is shown including outer bulge members <NUM> generally similar to those in <FIG> and inner bulge members here exemplary shown as those on the left hand side of <FIG>. On the right hand side of <FIG>, a pipe embodiment <NUM> is shown including outer bulge members <NUM> generally similar to those in <FIG> and inner bulge members here exemplary shown generally similar to those in <FIG>.

In embodiments having a bulge member made of a different material than the wall's base portion (e.g. pipes <NUM>, <NUM>, <NUM>), the material of these bulge members may be more elastic and/or soft than the remainder of the wall's base portion. By way of an example, an irrigation pipe having a base portion made of polyethylene material i.e. typically High-density polyethylene (HDPE), Medium-density polyethylene, or the like - may include bulge member(s) made of Low-density polyethylene (LDPE), Linear low-density polyethylene (LLDPE), or the like.

Attention is drawn to <FIG> illustrating generally similar pipes <NUM>, <NUM>, <NUM>, <NUM> (etc.) to those in <FIG>, respectively - however here shown including a drip emitter mounted to the inner side or face of the wall's base portion. Lateral sides of each drip emitter are here marked by the upright 'dashed lines' and as seen, each lateral side is possibly generally overlaid by a bulge member.

Strips of material illustrated in e.g. pipe embodiments <NUM>, <NUM> in <FIG>, which are located on inner sides of the pipe's base portion and hence in contact with drip emitters bonded to the inner side of the pipe; may be formed from a material more suitable for bonding to an emitter that is fitted to the pipe, than e.g. the remainder of the material of the pipe's wall e.g. in the pipe's base portion. <FIG> further illustrates an irrigation pipe embodiment <NUM> including a strip of material embedded within and/or flush with the pipe wall's base portion. Such strip is formed from a material that is more suitable for bonding to an emitter that is fitted to the pipe, than e.g. the remainder of the material of the pipe's wall e.g. in the pipe's base portion.

Improved suitability of material (such as of the strips in pipe embodiments <NUM>, <NUM>, <NUM>) for bonding to an emitter may be due to the strip having an MFI that is generally higher than the MFI of the remainder of the pipe wall e.g. in the pipe's base portion; and generally lower than the MFI of the material of the drip emitter bonded thereto. For example, for a drip pipe having a strip with an MFIs, a base portion with an MFIb and a drip emitter with an MFId - the relation of these MFI's may satisfy a ratio: MFIb ≤ MFIs ≤ MFId. In a non-binding example, thickness of the strip in at least certain embodiments may be from about <NUM> micrometers and up to about <NUM>% of an overall thickness of a pipe wall (e.g., including the base portion).

<FIG> illustrate various irrigation pipe and/or drip pipe embodiments. At the upper right hand side of <FIG>, a so-called 'tape' like thin walled drip pipe is illustrated in a flattened formation, where the drip emitter fitted to the pipe is located in-between two folds <NUM> formed in the pipe's wall. Such flattened shape resulting in the formation of the folds <NUM> may be created during a manufacturing process of such 'tapes', by intentionally flattening the pipe in order to perform certain procedures to the pipe, such as punching holes through the pipe.

In the pipe embodiment at the bottom of <FIG>, groups <NUM> of ribs (one possible group at the far side of the pipe is hidden) are configured to be placed adjacent locations about the pipe's wall where such folds occur in order to strengthen these areas. In addition, the pipe in <FIG> is seen including additional rids, such as ribs located along lateral sides of the emitter(s).

In <FIG>, a pipe embodiment only including such rib groups possibly at areas where folds are configured to occur, are illustrated. In <FIG>, such rib groups are configured to be placed on an inner side of the pipe wall (projecting inwardly from the pipe's base portion). Here, a possible gap <NUM> is formed within the rib group in order to urge the folds to occur within the strengthened area of the pipe wall i.e. within the rib groups. Additional possible ribs are here shown formed upon the base portion of the pipe's wall.

<FIG> illustrate further examples of pipe embodiments again including rib groups and possible additional ribs. <FIG> illustrates a pipe embodiment with ribs evenly distributed about its periphery, possibly like the embodiments seen in <FIG> and <FIG>.

<FIG> illustrates a pipe embodiment with adjacently located ribs formed about the pipe's periphery, with such ribs possibly being spaced apart by a distance generally similar to a rib width. <FIG> illustrates a pipe embodiment generally similar to that in <FIG>, however with ribs being absent along a segment about the pipe's periphery, possibly a segment along which drip emitters may be fitted to the inner side of the pipes wall. The distances here between adjacent ribs also appear slightly larger, for example equal to combined widths of two or more ribs.

Typically, mounting of a drip emitter to an inner side of an irrigation pipe to form a so-called drip pipe, may be performed by heat bonding. Such heat bonding may be performed during production of a drip pipe, by contacting a drip emitter to the hot melt of a pipe as the pipe exits an extruder and prior to solidification of the pipe wall. Possibly, also the drip emitter may be pre-heated in some cases to assist in the heat bonding to the pipe wall.

The area of contact between a drip emitter and a pipe wall may be susceptible to damage e.g. formation of cracks in the pipe wall, in some cases due to shear forces applied between the emitter and pipe during production or during later use. Such damage may be concentrated in some cases along locations in the pipe that overlie the lateral sides of the drip emitter.

Therefore, the bulge members may be seen in at least some embodiments also as "deposits" of excess material for increasing strength at 'strategic' locations where damage to the pipe wall may be expected to occur, such as in the shown embodiments along the lateral sides of the drip emitters. For example, during heat bonding of a drip emitter to a hot melt of a pipe wall, a bulge member being extruded together with the pipe's base portion or co-extruded upon the pipe's base portion may assist in providing additional material for increasing contact and consequently strength of bonding between the emitter and pipe. Such bulge members may also melt during the heat bonding process and may be designed to flow towards locations where additional strength to the pipe wall is required.

Bulges sufficient for providing "robustness" to drip irrigation pipes, such as thin-walled pipes or tapes, according to at least some embodiments of the invention may be defined as including a bulge height extending above the pipe's base portion that may be between about <NUM> to about <NUM> micro-meters, possibly between about <NUM> to about <NUM> micro-meters. In some cases, a bulge height extending above the pipe's base portion may be from as low as about <NUM> or <NUM> micro-meters and higher (possibly up to about <NUM> micro-meters). In the enlarged section provided at the lower left hand side of <FIG>, such bulge, here being bulge <NUM>, is illustrated extending a bulge height here marked as Hb above the pipe's base portion <NUM> having a value of between about <NUM> to about <NUM> micro-meters, possibly between about <NUM> to about <NUM> micro-meters, and further possibly between about <NUM> to about <NUM> micro-meters.

Pipe "robustness" may here refer to increased resistance of a pipe to failure and/or damage in agricultural applications such as when laying a pipe in a field or the like. Preferably, circumferential distribution of such bulges, possibly in a symmetrical manner, about the pipes' axis X - typically on an outer face of the pipe's base portion may be required for providing such "robustness". A bulge width Wb of such bulge, as bulge <NUM>, for providing "robustness" may similarly be within a range generally identical to about <NUM> to about <NUM> micro-meters, possibly between about <NUM> to about <NUM> micro-meters.

Bulge dimensions possibly suitable for providing additional deposits of material for locally "strengthening" certain areas of a pipe (e.g. due to bonding of a drip emitter thereto) and/or for providing "robustness" to a pipe (e.g. increased resistance to pipe failure and/or damage); may be defined in at least some embodiments of the invention as following. In one approach, pipes having relatively large wall thickness, such as a base wall thickness T reaching up to about <NUM> millimeters (<NUM> mil) - may be considered as being generally less susceptible to damage - such as that which may occur due to shear forces acting e.g. along lateral sides of drippers bonded to thinner walled pipes.

Thus, in accordance with such approach - a pipe having a relatively thin wall thickness T may be configured to include locally "strengthening" and/or "robust" bulges, such as the bulges <NUM> and/or <NUM> illustrated in <FIG> and <FIG> (see especially bulge <NUM> and bulge <NUM> in the enlarged section, respectively, of <FIG> and <FIG>), that extend a height Hs (for bulge <NUM>) and a height Hb (for bulge <NUM>) away from the pipe's base portion. Such bulges in preferred embodiments may be defined as having heights of at least up to a value of about <NUM> millimeters (<NUM> mil) minus T in order to provide an overall local pipe thickness of up to about <NUM> millimeters (<NUM> mil).

By way of an example, a pipe having a base portion thickness T of about <NUM> millimeters (<NUM> mil) may be configured to include one or more locally "strengthening" and/or "robust" bulge(s) having a height extending away from the pipe's base portion of up to about <NUM> millimeters (i.e. <NUM> minus <NUM> millimeters) in order to sufficiently locally "strengthen" and/or increase "robustness" of the pipe.

In a slight variance to the above approach, non-ribbed thin walled pipes conventionally offered in so-called 'thicknesses categories' of e.g. about <NUM> millimeter (<NUM> mil), <NUM> millimeter (<NUM> mil), <NUM> millimeter (<NUM> mil), <NUM> millimeter (<NUM> mil), (and so on); by provision of ribs/bulges in accordance with various embodiments of the invention - may be 'upgraded' to a higher 'thickness category' consequently rendering the pipe "stronger" and/or more "robust". This may be achieved by suitably choosing the bulge height (e.g. Hs, Hb) to locally increase wall thickness of a thin-walled pipe to one or more higher categories of wall thickness.

In one example, a pipe having a wall thickness at its base portion of about <NUM> millimeters (<NUM> mil); may be chosen to have ribs/bulges with heights of about <NUM> millimeter to "bridge" the gap and "upgrade" the pipe to an about <NUM> millimeters (<NUM> mil) pipe category. In a further example, a pipe having a wall thickness at its base portion of about <NUM> millimeters (<NUM> mil); may be chosen to have ribs/bulges with heights of about <NUM> millimeters in order to "bridge" the gap and "upgrade" the pipe to an about <NUM> millimeters (<NUM> mil) pipe category.

A width Ws of locally "strengthening" bulges may in at least some pipe embodiments be defined according to manufacturing tolerances of such pipes. In a pipe, for example, including locally "strengthening" bulges for providing deposits of melt-able material adjacent lateral sides of drip emitters of the pipe, width Ws may be chosen to be in a magnitude generally similar to an expected tolerance of placement of the drippers about the pipe's axis.

By way of an example, in a manufacturing procedure where a drip emitter may have a tolerance of about two millimeters in its placement about the pipe's axis upon base portion <NUM>, width Ws may be chosen to be generally similar to about two millimeters in order to compensate for such tolerance and ensure that the deposits of such locally "strengthening" bulge(s) is/are located at a suitable vicinity to the lateral sides of the drip emitters.

In the description and claims of the present application, each of the verbs, "comprise" "include" and "have", and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.

Further more, while the present application or technology has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and non-restrictive; the technology is thus not limited to the disclosed embodiments. Variations to the disclosed embodiments can be understood and effected by those skilled in the art and practicing the claimed technology, from a study of the drawings, the technology, and the appended claims.

The present technology is also understood to encompass the exact terms, features, numerical values or ranges etc., if in here such terms, features, numerical values or ranges etc. are referred to in connection with terms such as "about, ca. , substantially, generally, at least" etc. In other words, "about <NUM>" shall also comprise "<NUM>" or "substantially perpendicular" shall also comprise "perpendicular". Any reference signs in the claims should not be considered as limiting the scope.

Claim 1:
A drip irrigation pipe (<NUM>) having a pipe wall comprising a base portion (<NUM>) and a strip located on at least a portion of an inner side of the base portion facing into the pipe, the pipe (<NUM>) further comprising drip emitters (<NUM>) attached to the strip and the material of the strip being different than the material of the base portion,
the strip being substantially embedded in the base portion (<NUM>) flush with adjacent portions of the base portion that are exposed to fluid in the interior of the pipe, characterized by
the strip having a thickness of between about <NUM> micrometers and about <NUM>% of an overall thickness of a pipe wall.