Moisture-responsive irrigation device

Abstract

A device comprising: a housing defining an internal chamber, and configured to be positioned in the vicinity of a plant to be irrigated; an irrigation line passing transversely through the internal chamber and configured to transport irrigation liquid via capillary action or absorbency; and a moisture -responsive element enclosed within the internal chamber, wherein the moisture-responsive element is configured to expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing moisture, wherein the moisture-responsive element is enclosed within the internal chamber such that the expanding applies a compressive force to the irrigation line, and the contracting releases the compressive force, and wherein the irrigation line is configured such that the application of the compressive force restricts a flow of the irrigation liquid along the irrigation line, and the release of the compressive force restores the flow.

Description

MOISTURE-RESPONSIVE IRRIGATION DEVICECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from U.S. Application Ser. No. 63 / 635,423, filed April 17, 2024, entitled “AUTONOMOUS IRRIGATION DEVICE,” the contents of which are hereby incorporated herein in their entirety by reference.FIELD OF THE INVENTION

[0002] The invention relates to the field of moisture-responsive plant irrigation.BACKGROUND OF THE INVENTION

[0003] Various types of plants have different irrigation requirements depending on numerous factors, such as type of plant, rate of growth, relative humidity, and rate of air flow around the leaves. Additionally, environmental factors such as temperature, humidity, terrain or soil type, gravitational seepage, etc., may also affect the irrigation requirements of the various plants. Insufficient watering may result in a plant drying up and withering away. Conversely, excessive watering may also be detrimental to the plant and its root system.

[0004] The cultivation of healthy plants requires individual attention to the specific needs of different plants. This chore may be onerous and may lead to excessive or insufficient watering to the detriment of the plants. The use of a “one-size-fits-all” irrigation devices, where plants arranged along the same irrigation line receive the same quantity of water at the same time, poses a similar threat of excessive or insufficient watering. However, customized irrigation devices may be expensive, time consuming, require electricity and be intricate to operate. Further, due to the increased evaporation of water near the surface of soil, irrigation devices that sense moisture near where they are implanted and not at the base of the plant roots, may inadvertently overwater the plant. An automated, non-electronic, irrigation device that releases water based on the water content at the base of a plant’s roots is thus greatly needed.

[0005] The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art willbecome apparent to those of skill in the art upon a reading of the specification and a study of the figures.SUMMARY OF THE INVENTION

[0006] 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.

[0007] There is provided, in an embodiment, a moisture-responsive irrigation device comprising: a housing defining an internal chamber and configured to be positioned in the vicinity of a plant to be irrigated within a soil environment; an irrigation line passing transversely through the internal chamber and having an inlet end connected to a source of irrigation water and an outlet extending outside of the housing, wherein the irrigation line is configured to transport irrigation liquid at least partially via capillary action or absorbency; and a moisture-responsive element enclosed within the internal chamber, wherein the moisture-responsive element is configured to expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing moisture, wherein the moisture-responsive element is enclosed within the internal chamber such that the expanding causes the moisture-responsive element to apply a compressive force to the irrigation line, and the contracting releases the compressive force, and wherein the irrigation line is configured such that the application of the compressive force restricts a flow of the irrigation liquid along the irrigation line, and the release of the compressive force restores the flow.

[0008] There is also provided, in an embodiment, a method for moisture-responsive irrigation, comprising: providing a device comprising: a housing defining an internal chamber, an irrigation line passing transversely through the internal chamber and having an inlet end configured to be connected to a source of irrigation water and an outlet extending outside of the housing, wherein the irrigation line is configured to transport irrigation liquid at least partially via capillary action or absorbency; and a moisture- responsive element enclosed within the internal chamber, wherein the moisture- responsive element is configured to expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing moisture, wherein the moisture- responsive element is enclosed within the internal chamber such that the expanding causes the moisture-responsive element to apply a compressive force to the irrigationline, and the contracting releases the compressive force, and wherein the irrigation line is configured such that the application of the compressive force restricts a flow of the irrigation liquid along the irrigation line, and the release of the compressive force restores the flow; positioning the device in the vicinity of a plant to be irrigated within a soil environment, such that the outlet is positioned to irrigate the plant; and connecting the inlet end to a source of irrigation water.

[0009] In some embodiments, the irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, without pressurization.

[0010] In some embodiments, the irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, under at least a partial influence of gravity.

[0011] In some embodiments, the source of irrigation water is a reservoir, wherein the inlet end is dipped in the reservoir.

[0012] In some embodiments, the reservoir is elevated relative to the soil environment, wherein the method further comprises elevating the reservoir above relative to the soil environment.

[0013] In some embodiments, the expanding of the moisture-responsive element is proportional to an amount of the absorbing, wherein the applying of the compressive force is proportional to the expanding, wherein the restricting of the flow is proportional to the applying of the compressive force.

[0014] In some embodiments, the housing comprises at least one aperture configured to provide air and moisture communication between the moisture-responsive element and the ambient environment outside the housing.

[0015] In some embodiments, the housing is configured to be positioned such that the at least one aperture is at least partially above-ground, wherein the method further comprises positioning the device such that the at least one aperture is at least partially above-ground.

[0016] In some embodiments, the device further comprises a moisture transfer element configured to communicate moisture along its length, wherein a proximal end of the moisture transfer element is in moisture communication with the moisture-responsiveelement, wherein a distal end of the moisture transfer element is configured to be located at a desired location within the soil environment

[0017] In some embodiments, the desired location is other than the immediate soil environment vicinity of the housing, wherein the method further comprising locating the distal end of the moisture transfer element in a location other than the immediate soil environment vicinity of the housing.

[0018] In some embodiments, the desired location is near the root zone of the plant, wherein the method further comprising locating the distal end of the moisture transfer element is near the root zone of the plant.

[0019] In some embodiments, the device of any one of claims 1-12, further comprises a stake portion extending from a bottom of the housing and configured for inserting into the ground.

[0020] In some embodiments, the device further comprises a rigid element coupled to a bottom end of the moisture-responsive element, wherein the rigid element is configured to communicate the compressive force from the moisture-responsive element to the irrigation line.

[0021] In some embodiments, the moisture-responsive element is enclosed within the internal chamber such that the expanding is only possible in the direction of the irrigation line.

[0022] In some embodiments, the device further comprises a bias screw configured to threadedly engage with the housing such that an end portion of the bias screw can be advanced and retracted within the internal chamber so as to determine an initial position of the moisture-responsive element relative to the irrigation line.

[0023] 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 description.BRIEF DESCRIPTION OF THE FIGURES

[0024] Exemplary embodiments are illustrated in referenced figures. Dimensions of components and features shown in the figures are generally chosen for convenience andclarity of presentation and are not necessarily shown to scale. The figures are listed below.

[0025] FIGS. 1A-1C show a moisture-responsive irrigation device used in plant irrigation, according to certain embodiments.

[0026] FIGS. 2A-2B show a moisture-responsive irrigation device in perspective and side cross-sectional views, according to certain embodiments.

[0027] FIGS. 3A-3C show a moisture-responsive irrigation device is cross-sectional side views, according to certain embodiments.

[0028] FIG. 3D shows a moisture transfer element of a moisture-responsive irrigation device, according to certain embodiments.

[0029] FIGS. 4A-4B show the manner in which the moisture-responsive element acts upon the irrigation line.

[0030] FIGS. 5A-5B show an irrigation plate, according to certain embodiments.DETAILED DESCRIPTION OF THE INVENTION

[0031] Disclosed herein is a moisture-responsive irrigation device for regulating the irrigation of a plant embedded in a soil environment, based on sensing the moisture content in the plant’s soil environment.

[0032] In an exemplary embodiment, the moisture-responsive irrigation device comprises:A housing comprising an internal chamber and a stake portion extending from a bottom end thereof and configured for inserting into the ground near a plant to be irrigated.In some embodiments, the housing comprises one or more apertures configured to provide air and / or moisture communication between the internal chamber and the ambient environment outside the housing.In some embodiments, the device may be configured for embedding in the ground near a plant by inserting the stake portion into the ground, such that the internal chamber may be entirely above ground, wherein the apertures provide air and / ormoisture communication between the internal chamber and the ambient air environment outside the housing.In some embodiments, the device may be configured for embedding in the ground near a plant by inserting the stake portion into the ground, such that the internal chamber may be at least partially embedded in the soil environment. In this variation, the apertures may be partially exposed to the ambient air environment and partially exposed to the soil environment, so as to provide air and / or moisture communication between the internal chamber and the ambient air environment outside the housing and / or the soil environment outside the housing.In some embodiments, the device may be configured for embedding in the ground near a plant by inserting the stake portion into the ground, such that the internal chamber may be completely embedded in the soil environment, at any desired depth. In this variation, the apertures may be exposed only to the soil environment, so as to provide air and / or moisture communication between the internal chamber and the soil environment outside the housing.An irrigation line passing transversely through the internal chamber and configured to provide irrigation (e.g., water or another liquid or fluid) to a plant in the vicinity of the device. In some embodiments, the irrigation line may be any line, tubing, hose, pipe or conduit configured to connect to a source of irrigation liquid or fluid, and to contain and transport the irrigation liquid or fluid along a flow path which passes transversely through the internal chamber, to an irrigation point outside the housing.In some examples, the irrigation line may be any conduit or hose configured to contain and transport an irrigation liquid along an internal passageway under pressure and / or assisted by any other external force, such as gravity. In such cases, the irrigation line may be connected to an irrigation source, such as a water line or a reservoir, wherein the irrigation liquid is transported along the flow path under pressure and / or assisted by any other external force, such as gravity.In other examples, the irrigation line may not define a conduit or hose, but rather may comprise any medium configured to transport a liquid or fluid by capillary or similar action, completely or partially without the assistance of an external force such as pressurization. In such embodiments, such medium may compriseany suitable woven or similar structure made of intertwined fibers having desired absorbency, wicking or capillary properties, or from any suitable porous material. In such cases, the irrigation line may be configured to absorb or soak up irrigation liquid, e.g., by dipping an end of the irrigation line in a suitable reservoir. In some cases, the irrigation line may absorb moisture from the ambient environment. A potential advantage of this variation is in that it provides for precise moisture- responsive releasing of irrigation for a plant, based on the amount of water actually available to the plant at its immediate soil environment, without the need to connect the irrigation system to a water supply line. Thus, for example, a plant may be watered in precise manner from a nearby small reservoir, which can supply the needs of the plant for an extended period of time, without the need for connecting the irrigation supply line to the water supply system. The irrigation line may be configured to absorb or soak up irrigation liquid from the reservoir, e.g., by dipping an end of the irrigation line in the reservoir, while the device is configured to release the water for the plant according to precise sensing of the moisture level in the soil. This provides a long-term watering solution which avoids the need for frequent manual watering of the plant, on the one hand, and the need to connect the irrigation system to a water supply line, on the other hand.In all of these examples, the irrigation line is configured such that (i) the flow of liquid along the flow path of the irrigation line can be restricted or completely blocked upon the application of a local compressive force on the irrigation line, and (ii) the flow of liquid along the flow path of the irrigation line can be fully or partially restored upon the cessation of the application of a local compressive force on the irrigation line.A moisture-responsive element housed and enclosed within the internal chamber. The moisture-responsive element is configured or expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing or loss of moisture.In some embodiments, the moisture-responsive element may be or may comprise a hygroscopic material which exhibits dimensional variation in response to moisture absorption and desorption.In some embodiments, the moisture-responsive element is configured to expand in volume in response to absorbing moisture from the surrounding environment, and to contract in volume in response to desorbing to loss of moisture to the surrounding environment.In some embodiments, the moisture-responsive element is configured or expand in volume in proportion to the level of absorbed or desorbed moisture, based on a predetermined coefficient of expansion.In some embodiments, the moisture -responsive element is positioned and enclosed within the internal chamber such that any expansion of the moisture- responsive element upon absorption of moisture (e.g., to the ambient environment) causes the moisture -responsive element to apply local compressive force on the portion of the irrigation line passing through the internal chamber. Conversely, any contraction of the moisture -responsive element upon desorption or loss of moisture (e.g., to the ambient environment) causes the moisture- responsive element to release the compressive force applied on the irrigation lineIn some embodiments, the moisture-responsive element is housed within the internal chamber such that it is in air and / or moisture communication, via the apertures of the housing, with the ambient environment outside the housing. Thus, the moisture-responsive element is configured to absorb and desorb moisture depending on the humidity level of the ambient air environment.Accordingly, when the housing is positioned such that the internal chamber is entirely above ground, the moisture-responsive element is in air and / or moisture communication, via the apertures of the housing, with the ambient air environment outside the housing.When the housing is positioned such that the internal chamber is at least partially embedded in the soil environment, the moisture-responsive element is in air and / or moisture communication, via the apertures of the housing, with the ambient air environment outside the housing and / or the soil environment outside the housing. Thus, the moisture -responsive element is configured to absorb and desorb moisture depending on the humidity level of the ambient air environment and / or the ambient soil environmentWhen the housing is positioned such that the internal chamber is completely embedded in the soil environment, the moisture-responsive element is in air and / or moisture communication, via the apertures of the housing, within the soil environment outside the housing. Thus, the moisture-responsive element is configured to absorb and desorb moisture depending on the humidity level of the ambient soil environmentOptionally, the present device may comprise a moisture transfer element for communicating moisture to the moisture -responsive element from a desired location within the soil environment in the immediate vicinity of the device, for example, the moisture transfer element may be configured to communicate moisture to the moisture-responsive element from at or near the root zone of the plant.In certain embodiments, the moisture transfer element defines an elongated wick or similar element. In some embodiments, the moisture transfer element is configured to transfer moisture along its length, from a distal end thereof which is placed at any desired location within the soil environment of the plant, to a proximal end thereof, which is in moisture communication with the moisture- responsive element inside the internal chamber.In some embodiments, the moisture transfer element ensures that moisture levels to which the moisture-responsive element is exposed reflect moisture levels at a desired location within the soil environment, other than the immediate soil environment of the device. This is achieved by communicating, through capillary action, the moisture level to which the distal end of the moisture transfer element is exposed, to its proximal end and to the moisture-responsive element.For example, in some embodiments, the moisture transfer element is configured as a wicking sleeve whose proximal end fits around the housing, such that it fully or partially covers the apertures. The distal end of the moisture transfer element may then be positioned at any desired location within the soil environment of the plant, e.g., at or near the root zone of the plant. Thus, the moisture transfer element communicates, through capillary action, the moisture level to which the distal end of the moisture transfer element is exposed at the root zone, to its proximal end. As noted above, the proximal end of the moisture transfer elementis in moisture communication with the moisture-responsive element inside the internal chamber, and thus the moisture -responsive element can react to the moisture levels existing at the root zone of the plant, rather than to those at the immediate vicinity of the device.In some embodiments, the moisture transfer element may be made of a woven material or structure, such as a sleeve or a rope made of fibers having desired wicking properties, such as manila hemp, hemp, cotton, polypropylene, polyester, aramid, or the like. In some embodiments, the moisture transfer element may be composed of a porous material, e.g., a sponge composed of polypropylene, polyether, polyester, cellulose, or the like.

[0033] The moisture-responsive irrigation device may be configured such that the normal flow rate through the irrigation line is sufficient to prevent clogging of the irrigation line. In certain embodiments, the irrigation line may comprise a check valve, which may be configured to prevent insects, soil, or debris from entering the irrigation line and potentially clogging or damaging the irrigation line. In certain embodiments, an opening of the irrigation line through which water pours out of the irrigation line may be located at a predetermined distance from the moisture-responsive element, to provide sufficient moisture levels in the soil environment prior to the moisture-responsive element expanding or swelling and compressing the irrigation line.

[0034] Optionally, the moisture-responsive irrigation device comprises a bias screw, which is configured to control an initial maximum rate of water flow through the irrigation line. Tightening the bias screw applies an initial compressive force to the moisture-responsive element, which in turn compresses the irrigation line, thereby limiting the maximum flow rate through the irrigation line. Conversely, loosening the bias screw reduces the constant force applied to the irrigation line through the moisture- responsive element, thus increasing the maximum flow rate up to the full flow rate of the irrigation line.

[0035] In certain embodiments, the irrigation line may irrigate the soil environment from a surface of the soil environment, such that the water seeps through the soil environment. In other embodiments, the device may comprise an irrigation plate or mat disposed underneath a plant pot or forming an integral part thereof; or embedded in the soil underneath the roots of the plant. The irrigation plate is configured to receive andretain a desired amount of irrigation, which is then absorbed and controllably disperses upwards through the soil environment. Moisture may be absorbed into the soil environment from the irrigation plate through, e.g., osmotic transference. The moisture dispersed through the soil environment and reaches the roots, thus providing the necessary water for the plant. The irrigation plate may disperse the water over a larger surface area thereby ensuring consistent optimal moisture levels throughout the soil environment. Irrigation using the irrigation plate may also reduce the mineral content or salinity of the water that reaches the roots, as only the water is absorbed by the soil environment, while any mineral content remains as residue in the irrigation plate.

[0036] In some embodiments, the moisture -responsive irrigation device is nonelectronic. In some embodiments, the irrigation device operates entirely mechanically. In some embodiments, the moisture-responsive irrigation device is configured to be completely embedded in soil. In some embodiments, the moisture-responsive irrigation device is configured to be partially embedded in soil. In some embodiments, the moisture-responsive irrigation device is configured to be partially embedded in soil such that the moisture-responsive element contacts the air.

[0037] In certain embodiments, the moisture -responsive irrigation device further comprises a moisture transfer element configured to communicate moisture levels to the moisture-responsive element from a predetermined location that is not in the immediate vicinity of the moisture -responsive irrigation device, e.g., from the irrigation plate. Communication of moisture levels through the moisture transfer element may be performed through osmotic transference towards the moisture-responsive element. The moisture transfer element may define a predetermined distance between the moisture- responsive element and a location at which the irrigation line provides water for irrigation, e.g., at the irrigation plate. The moisture-responsive element may be arranged at a predetermined height above the irrigation plate, such that when a predetermined volume of water fills the irrigation plate, the moisture-responsive element communicates such moisture level to the moisture-responsive element. Alternatively, the moisture transfer element may be coupled to the irrigation plate. Thus, once a desired volume of water is provided to the irrigation plate, the moisture level is communicated to the moisture-responsive element via the moisture transfer element. This enables the moisture-responsive irrigation device to respond more effectively by restricting orstopping further irrigation once the irrigation plate has received a sufficient supply of water.

[0038] Herein throughout, the term "moisture -responsive," or any grammatical inflection thereof refers to the property of the material to absorb a fluid medium, typically, but not exclusively, aqueous, with an accompanying increase in the volume of such material. In some embodiments, moisture-responsive is also shrinkable. In some embodiments, moisture-responsive is able to change volume in response to the absorbance or loss of moisture.

[0039] In some embodiments, under conditions known in the art, the moisture- responsive material has the ability to expand by a volume of at least 0.1, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5 or 5 ml, upon immersing thereof in 100 grams of water. Each possibility represents a separate embodiment of the invention. In some embodiments, under conditions known in the art, the moisture-responsive material has the ability to expand by a volume of between 0.1- 5.0, 0.1-3, 0.1- 1, 0.1-0.75, 0.1-0.5, 0.25-5, 0.2-3, 0.25-1, 0.25-0.5, 0.5-5, 0.5-3, 0.5-1, 1- 5, or 1-3 ml, upon immersing thereof in 100 grams of water. Each possibility represents a separate embodiment of the invention. In some embodiments, the moisture-responsive material has the ability to expand by at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100% of its volume upon immersion in water. Each possibility represents a separate embodiment of the invention.

[0040] In some embodiments, the expanding is at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or in some embodiments, even completely reversible, upon the release of the fluid medium from the moisture-responsive material. In some embodiments, the expanding is 100% reversible. In some embodiments, the moisture-responsive element is a reversibly moisture-responsive element, configured to expand when absorbing moisture and to shrink when losing moisture. In some embodiments, loss of moisture is due to evaporation, drying and / or diffusion. In some embodiments, the tube is disposed adjacent to the moisture-responsive element inside the housing such that a shrinking of an expanded moisture -responsive element releases the irrigation line, thereby unrestricting water flow therethrough. Optionally, the fluid medium may be released from the moisture-responsive material by evaporation or drying.

[0041] The moisture-responsive element may be made of any material that changes volume due to intake or egress of moisture from the element. Such moisture-responsive materials are well known in the art and any such element may be used, including but not limited to, hydrogels, clays, slurries, rubber and the like. In some embodiments, the moisture-responsive material comprises rubber. In some embodiment, the rubber is natural rubber. In some embodiments, the rubber is vulcanized rubber. In some embodiments, the rubber is artificial rubber. In some embodiments, the artificial rubber is chemically combined with a hydrophilic material or compound. In some embodiments, the moisture-responsive element comprises a hydrophilic material. In some embodiments, the moisture-responsive element comprises a material capable of changing volume and a hydrophilic material. In some embodiments, the moisture-responsive element is capable of changing volume in response to moisture intake or egress. In certain embodiments, the moisture-responsive element may be made of various forms of silicate minerals such as, and without being limited thereto, bentonite clay. The moisture- responsive element may have varying levels of hydrophilic and solvating properties. Without being bound by any particular theory, the expanding of bentonite may occur due to water absorption at a platelet surface level and / or by osmotic repulsive forces, forcing platelets to detach and spread out. In some types of bentonite, such as sodium bentonite with sodium cation prevalence (Na+), water may penetrate through platelets, forcing platelets apart, thus leading to expanding. Conversely, calcium bentonite with calcium cation prevalence (Ca2+) may have low absorption properties due to a strong positive charge preventing water from penetrating through the platelets. Thus, in calcium bentonite with calcium cation prevalence platelets are more likely to flake off rather than expand.

[0042] When bentonite is dispersed in water, highly stable colloidal suspensions may be formed with high viscosity and thixotropy. At high enough concentrations of bentonite, such suspensions may take on gel characteristics. Suspensions may form when water- molecules penetrate platelet interlayers. Hydrogen bridge bonds may be formed by the hydrogen atoms contained in water molecules. Platelets become isolated from each other, while bonded through interposition of water. When left still, the bentonite may form a mesh by incorporating water, causing the bentonite to jellify. Conversely, under mechanical stress, these bonds may partially break, thus allowing platelets to move more freely. Viscosity under these conditions is lower than at rest. Bentonite may consistof a varying density when dry, e.g. within a range of 2.2 grams / centimeter cubed (g / cm3) to 2.8 g / cm3. Milled bentonite may have an apparent density that may vary depending on mill fineness, ranging from 0.7 g / cm3to 0.9 g / cm3.

[0043] In some embodiments, the moisture-responsive element may comprise any material or combination of one or more materials which exhibit the property of hygroscopic expanding, i.e., attracting and holding water molecules from the surrounding environment, which causes the material to expand in volume. In some embodiments, the moisture-responsive element may comprise one or a combination or two or more high- absorbency polymers. In some embodiments, such polymers may be blended with one or more filler materials, hydrophilic materials, and / or an elastomeric base material.

[0044] FIGS. 1A-1C show a plant irrigation arrangement utilizing a moisture- responsive irrigation device 100, according to certain embodiments. Device 100 is configured to irrigate a plant 170 in soil environment 175.

[0045] Device 100 comprises a housing 120 which defines a cylindrical or similar body having an internal chamber 122 (shown in FIGS. 2A-2B), and configured to be positioned within the vicinity of a plant to be irrigated. In some embodiments, housing 120 comprises one or more apertures 136 configured to provide air and / or moisture communication between internal chamber 122 and the ambient environment outside housing 120.

[0046] Device 100 further comprises a stake portion 124 extending from a bottom of housing 120 and configured to be inserted into the ground near plant 170. In the scenario of FIG. 1A, housing 120 is above-ground, wherein apertures 136 are completely aboveground. In this scenario, apertures 136 provide air and / or moisture communication between internal chamber 122 and the ambient air environment outside housing 120.

[0047] Device 100 further comprises an irrigation line 110 which passes transversely through a center of internal chamber 122. Irrigation line 110 has an inlet end 111 connected to a source of irrigation liquid, such as a reservoir (not shown). Irrigation line 110 is configured to transport the irrigation liquid from the source, through the portion of irrigation line 110 passing through internal chamber 122, and through an outlet 112 which extends outside of housing 120, to provide irrigation (e.g., water) to plant 170.

[0048] Moisture-responsive irrigation device 100 further comprises a moisture- responsive element 130 housed within internal chamber 122. Moisture-responsiveelement 130 is housed and enclosed within the housing, adjacent to irrigation line 110, and configured to expand from moisture absorption and contract upon moisture desorption. When moisture-responsive element 130 expands, it is configured to apply local compressive force on the portion of irrigation line 110 passing through internal chamber 122, thereby restricting or completely stopping the passage of irrigation liquid therethrough. Conversely, when in a contracted state upon desorption or loss of moisture (e.g., to the ambient environment), moisture-responsive element 130 releases the compressive force applied on irrigation line 110, wherein the passage of irrigation liquid is restored through irrigation line 110 and via outlet 112 to plant 170.

[0049] Moisture-responsive irrigation device 100 further comprises an optional moisture transfer element 152 for communicating moisture from a desired location within soil environment 175 that is external to housing 120 (e.g., root zone 172), to moisture-responsive element 130.

[0050] As can be seen in FIG. 1A, the distal end of moisture transfer element 152 is positioned at any desired location within soil environment 175, e.g., at or near the root zone 172 of plant 170. Thus, moisture transfer element 152 communicates, through capillary action, the moisture level to which the distal end of moisture transfer element 152 is exposed at the root zone 172, to its proximal end. The proximal end of moisture transfer element 152 is in moisture communication with moisture -responsive element 130 within internal chamber 122, and thus moisture-responsive element 130 can react to the moisture levels at the root zone 172 of plant 170, rather than, or in addition, to those at the immediate vicinity of device 100 at ground level. Thus, device 100 solves the technical problem of precise moisture-responsive releasing of irrigation water for plant 170, based on the water actually available to plant 170 at the root zone 172. Because roots are the organs of plant 170 that take in water and nutrients into the body of the plant, having an accurate indication of available hydration at the root zone 172 (rather than at ground surface) is crucial for precise irrigation management. Using the moisture transfer element 152, moisture-responsive element 130, which is located wholly or partially above-ground, is exposed to moisture levels which reflect those found at the root zone 172, rather than at or near ground level. At the same time, moisture -responsive element 130 is able to react with sufficient immediacy in response to changes in the measured hydration levels, because apertures 136 provide exposure to ambient air, which allows moisture-responsive element 130 to quickly and efficiently desorb stored moistureinto the air environment. This arrangement provides for moisture-responsive adaptation of the irrigation amounts to the actual water available to plant 170, which is a function of the water uptake of plant 170 and the hydrological properties of the soil within environment 175. For example, when dealing with plants having large water uptake and / or soil having lower water retention capacity, the soil around the root zone 172 will take longer to get water-logged, and moisture from the root zone 172 will take longer to reach moisture-responsive element 152, thereby extending the irrigation period before shut-off. Conversely, when the soil has high water retention capacity and / or plant 170 has lower water uptake, the soil surrounding the roots will retain more hydration, thereby indicating higher hydration levels at the root zone 172 and causing earlier irrigation shutoff by device 100.

[0051] FIG. IB shows moisture-responsive irrigation device 100 configured to irrigate plant 170 in soil environment 175. Stake portion 124 may be inserted into the ground near plant 170, such that housing 120 is at least partially below-ground, wherein apertures 136 are partially below-ground and partially above-ground. In this scenario, apertures 136 provide air and / or moisture communication between internal chamber 122 and both of soil environment 175 (near ground level) and the ambient air environment outside housing 120. Optionally, moisture transfer element 152 may be used (as shown in FIG. 1 A), and positioned such that a distal end thereof is located at any desired location within soil environment 175, e.g., at or near root zone 172 of plant 170. When moisture transfer element 152 is used in this implementation, it communicates, through capillary action, the moisture level to which the distal end of moisture transfer element 152 is exposed at the root zone 172, to its proximal end. As noted above, the proximal end of moisture transfer element 152 is in moisture communication with moisture -responsive element 130 housed inside internal chamber 122, and thus moisture-responsive element 130 can react to both the moisture levels at the root zone 172 of the plant and to the moisture levels at the immediate soil vicinity of device 100 above-ground.

[0052] FIG. 1C shows moisture-responsive irrigation device 100 configured to irrigate a plant in soil environment 175. Stake portion 124 may be inserted into the ground near plant 170, such that housing 120 is at least partially below-ground, wherein apertures 136 are completely below-ground. In this scenario, apertures 136 provide air and / or moisture communication between internal chamber 122 of housing 120 and soil environment 175 outside housing 120 (i.e., near ground level). Optionally, moisture transfer element 152may be used (shown in FIG. 1A), and positioned such that a distal end thereof is located at any desired location within soil environment 175, e.g., at or near be the root zone 172 of plant 170.

[0053] Device 100 will now be described in detail with continuous reference to FIGS. 1A-1C, and with reference to FIGS. 2A-2B, which illustrate a moisture-responsive irrigation device 100 in perspective and side cross-sectional views.

[0054] Device 100 comprises housing 120 which has a cylindrical or similar body defining an internal chamber 122. Housing 120 may be made of any suitable material, such as any suitable polymer.

[0055] In some embodiments, housing 120 comprises one or more apertures 136 configured to provide air and / or moisture communication between internal chamber 122 and the ambient environment outside housing 120. Housing 120 may comprise apertures 136 which may be configured to expose internal components disposed within internal chamber 122 to the ambient environment, e.g., soil environment 175 and / or atmospheric air. Housing 120 may further comprise side openings (not shown) which allow for an irrigation line 110 to pass transversely through housing 120 and across substantially the center of internal chamber 122. The openings may be arranged on opposite sides of housing 120, to enable passing irrigation line 110 transversely through internal chamber 122.

[0056] In some embodiments, housing 120 comprises stake portion 124 extending from a bottom end thereof, and configured for inserting into the ground or any soil environment (e.g., in a planter or flowerpot) near a plant to be irrigated. As shown in FIG. 1A, in some embodiments, device 100 may be configured for embedding in the ground near a plant by inserting stake portion 124 into the ground, such that housing 120 or at least apertures 136 are entirely above ground, wherein apertures 136 provide air and / or moisture communication between internal chamber 122 of housing 120 and the ambient air environment outside housing 120.

[0057] As shown in FIG. IB, in some embodiments, device 100 may be configured for embedding in the ground near a plant by inserting stake portion 124 into the ground, such that housing 120 or at least apertures 136 are partially embedded in soil environment 175, at any desired depth. In this manner of use, apertures 136 may be partially exposed to the ambient air environment and partially exposed to soil environment 175, so as to provideair and / or moisture communication between internal chamber 122 of housing 120 and the ambient air environment outside housing 120 and / or soil environment 175 outside housing 120.

[0058] As shown in FIG. 1C, in some embodiments, device 100 may be configured for embedding in the ground near a plant by inserting stake portion 124 into the ground, such that housing 120 may be completely underground within soil environment 175, at any desired depth. In this manner of use, apertures 136 may be exposed only to soil environment 175, so as to provide air and / or moisture communication between internal chamber 122 of housing 120 and soil environment 175 outside housing 120.

[0059] In some embodiments, moisture-responsive irrigation device 100 comprises irrigation line 110 which passes transversely through the internal chamber 122, e.g., via suitable opposing openings in housing 120 (not shown).

[0060] Irrigation line 110 has an inlet end 111 configured to be connected to a source of irrigation liquid. For example, inlet end 111 may be dipped in a water reservoir (not shown). Irrigation line 110 is configured to transport the irrigation liquid from the source, through the portion of irrigation line 110 passing through internal chamber 122, and through an outlet 112 which extends outside of housing 120, to provide irrigation (e.g., water) to plant 170. Irrigation line 110 is thus configured to provide irrigation (e.g., water) to a plant in the vicinity of the device, via outlet 112 thereof (shown, e.g., in FIGS. 1A-1C).

[0061] In some variations, irrigation line 110 comprises any medium configured to transport an irrigation liquid or fluid by capillary or similar action, completely or partially without the assistance of an external force, such as pressurization. In some embodiments, irrigation line 110 may comprise any medium configured to transport an irrigation liquid or fluid by capillary or similar action, which may be at least partially assisted by the force of gravity. In some embodiments, such medium may comprise any suitable woven or similar structure made of intertwined fibers having desired wicking or capillary properties. Some examples include manila hemp, hemp, cotton, polypropylene, polyester, aramid, or the like. In some embodiments, irrigation line 110 may be made from any suitable porous material, such as a sponge composed of polypropylene, polyether, polyester, cellulose, or the like. In all such cases, irrigation line 110 may be configured to absorb or soak up irrigation liquid, e.g., by dipping inlet end 111 ofirrigation line 110 in a suitable reservoir. In other examples, irrigation 110 line may be configured to absorb moisture from the ambient environment. In some examples, the capillary action which transports the liquid along irrigation line 110 may be assisted by gravity.

[0062] A potential advantage of irrigation line 110 as configured in this manner is in that it provides for transport of irrigation liquid along its length without the need to connect irrigation line 110 to a water supply line, e.g., a pressurized water supply line, such as a municipal water system. Thus, for example, irrigation line 110 may be used to water plant 170 from a nearby small reservoir (which may be placed at an elevation relative to soil environment 175 of plant 170), which can supply the needs of plant 170 for an extended period of time, without the need for connecting irrigation line 110 to a water supply system. This may be particularly advantageous for plants located in areas without ready access to a water supply network. Irrigation line 110 is thus configured to absorb or soak up irrigation liquid from the reservoir, e.g., by dipping inlet end 111 of irrigation line 110 in the reservoir, and transporting the liquid to plant 170, e.g., by capillary action, potentially with the help of gravity. This provides an extended-term watering solution which avoids the need for frequent manual watering of plant 170, on the one hand, and the need to connect the irrigation system to a water supply line, on the other hand.

[0063] In all of these variations, irrigation line 110 is configured such that (i) the flow of liquid along the length of irrigation line 110 can be restricted or completely blocked upon the application of a local compressive force on irrigation line 110, as shall be further detailed hereinbelow, and (ii) the flow of liquid along the length of irrigation line 110 can be fully or partially restored upon the release of the applied local compressive force on irrigation line 110.

[0064] In other examples, irrigation line 110 may be any conduit or hose configured to contain and transport an irrigation liquid along an internal passageway under pressure and / or assisted by any other external force, such as gravity. In such cases, irrigation line 110 may be connected to a water supply source, such as a water supply system, wherein the irrigation liquid is transported along the flow path under pressure and / or assisted by any other external force, such as gravity. In this example, irrigation line 110 may be composed of silicone, e.g., silicone rubber, to withstand the water pressure and to prevent the walls of irrigation line 110 from adhering together when a compressive force isapplied to irrigation line 110. In certain embodiments, irrigation line 110 may comprise an external diameter within a range of 3-5 millimeter (mm) and an internal diameter within a range of 1-3 mm.

[0065] Reference is made to FIGS. 3A-3C which show device 100 is cross-sectional side views.

[0066] As seen in FIGS. 3A-3B, moisture-responsive irrigation device 100 may further comprise moisture-responsive element 130 housed within internal chamber 122. Moisture-responsive element 130 may define a cylindrical or similar small body configured to be received and housed within internal chamber 122. In some embodiments, moisture-responsive element 130 may define a cylindrical or similar small body configured to be received and housed within internal chamber 122 in a close fit relative to an internal bore of internal chamber 122.

[0067] In some embodiments, moisture -responsive element 130 may comprise a hygroscopic material which exhibits dimensional variation in response to moisture absorption and desorption. In some embodiments, moisture-responsive element 130 is configured to expand in volume in response to absorbing moisture from the surrounding environment, and to contract in volume in response to desorbing to loss of moisture to the surrounding environment. In some embodiments, moisture -responsive element 130 is configured or expand in volume in proportion to the level of absorbed or desorbed moisture, based on a predetermined coefficient of expansion.

[0068] In some embodiments, moisture-responsive element 130 is positioned and enclosed within internal chamber 122 such that any expansion of moisture -responsive element 130 upon absorption of moisture (e.g., to the ambient environment) causes moisture-responsive element 130 to impinge or apply local compressive force on the portion of irrigation line 110 passing through internal chamber 122. Conversely, any contraction of moisture-responsive element 130 upon desorption or loss of moisture (e.g., to the ambient environment) causes moisture-responsive element 130 to release the compressive force applied on irrigation line 110.

[0069] In some embodiments, moisture-responsive element 130 is enclosed within internal chamber 122 such that any expansion of moisture-responsive element 130 upon absorption of moisture is in the direction toward irrigation line 110, and thus causes the impingement or application of a local compressive force on irrigation line 110. In someembodiments, moisture-responsive element 130 is enclosed within internal chamber 122 such that irrigation line 110 is positioned between moisture-responsive element 130 and a bottom end of internal chamber 122, and thus any expansion of moisture-responsive element 130 upon absorption of moisture is in the direction toward irrigation line 110, and causes the application of a local compressive force on irrigation line 110.

[0070] In some embodiments, moisture-responsive element 130 is enclosed within internal chamber 122 such that side walls of internal chamber 122 restrict a lateral expansion of moisture-responsive element 130. In some embodiments, moisture- responsive element 130 is enclosed within internal chamber 122 such that a top end of moisture-responsive element 130 abuts against a cap 138 of housing 120 (e.g., shown in FIG. 3A), wherein a bottom end of cap 138 acts as a stop which restricts an expansion of moisture-responsive element 130 toward to top end of housing 120. Thus, moisture- responsive element 130 is positioned and housed within internal chamber 122 such that it can only expand in the direction toward irrigation line 110. Irrigation line 110 is positioned between moisture -responsive element 130 and a bottom end of housing 120. Thus, any expansion of moisture-responsive element 130 upon absorption of moisture is in the direction toward irrigation line 110, and causes the application of a local compressive force on irrigation line 110.

[0071] In some embodiments, moisture -responsive element 130 may be coupled to a rigid element 132, which is positioned between a bottom end of moisture-responsive element 130 and irrigation line 110. Rigid element 132 may be configured to communicate the compressive force applied by the expansion of moisture-responsive element 130 to the irrigation line 110. It will be appreciated that moisture-responsive element 130 may comprise a pliable or malleable material which lacks sufficient rigidity for effectively applying a compressive force to the irrigation line 110 without causing some deformation of moisture-responsive element 130 itself. Rigid element 132 may be coupled to moisture-responsive element 130 between a bottom end of moisture- responsive element 130 and irrigation line 110, such that when moisture-responsive element 130 expands in the direction of irrigation line 1220, rigid element 132 provides for an efficient local impingement of the force applied moisture-responsive element 130 to irrigation line 110. Rigid element 132 may define, e.g., a circular or semispherical element positioned at the bottom end of moisture-responsive element 130. In some embodiments, rigid element 132 has a diameter substantially similar to that of on the sideadjacent to the moisture-responsive element, such the any deformation of the moisture- responsive element 130 in minimized. In some embodiments, rigid element 132 comprises two hemispheres pushing with their curved surfaces against the flexible tune 110 from opposite sides. The first of said hemispheres is coupled at its flat surface to the moisture-responsive element 130, and the second of said hemispheres is disposed between the closed end of housing 120 and the irrigation line 110. Rigid element 132 may be made of any suitable material e.g., a polymer or a metal. Rigid element 132 may be of any shape such that it applies the force of the expansion of moisture-responsive element 130 to irrigation line 110. Rigid element 132 may have a flat surface that engages or contacts moisture-responsive element 130. The flat surface may completely cover or partially cover moisture-responsive element 130. Rigid element 132 may be curved or come to a point (like a triangle) where it contacts and applied force to irrigation line 110.

[0072] In some embodiments, moisture -responsive element 130 is housed within internal chamber 122 such that it is in air and / or moisture communication, via apertures 136 of housing 120, with the ambient environment outside housing 120. Accordingly, when housing 120 is positioned entirely above ground, moisture-responsive element 130 is in air and / or moisture communication, via apertures 136 of housing 120, with the ambient air environment outside housing 120. When housing 120 is partially embedded in soil environment 175, moisture-responsive element 130 is in air and / or moisture communication, via apertures 136 of housing 120, with the ambient air environment outside housing 120 and / or soil environment 175 outside housing 120, depending on the depth of embedding of housing 120. When housing 120 is completely embedded in soil environment 175, moisture-responsive element 130 is in air and / or moisture communication, via apertures 136 of housing 120, within soil environment 175 outside housing 120.

[0073] It should be noted that when moisture -responsive element 130 is positioned such that it is at least partially in air and / or moisture communication with the ambient air environment outside housing 120, this allows moisture -responsive element 130 to desorb moisture more rapidly.

[0074] In some embodiments, moisture -responsive element 130 is configured to expand in volume when absorbing moisture. In some embodiments, moisture-responsive element 130 may comprise any material or combination of one or more materials which exhibit the property of hygroscopic expanding, i.e., attracting and holding watermolecules from the surrounding environment, which causes the material to expand in volume. In some embodiments, moisture-responsive element 130 may comprise one or a combination or two or more high-absorbency polymers. In some embodiments, such polymers may be blended with one or more filler materials, hydrophilic materials, and / or an elastomeric base material.

[0075] Moisture-responsive element 130 may be inserted into internal chamber 122 through a top end of housing 120, wherein it is enclosed within internal chamber 122 by cap 138 or bias screw 140, as the case may be.

[0076] FIGS. 4A-4B show the manner in which moisture-responsive element 130 acts upon irrigation line 110. As can be seen in FIG. 4A, when moisture-responsive element 130 is in a relatively dry environment (which may be air or soil environment), moisture- responsive element 130 does not absorb moisture, or even desorbs moisture to the surrounding environment. Thus, moisture -responsive element 130 contracts in volume into a state wherein it does not apply force or impinge on irrigation line 110. Conversely, as can be seen in FIG. 4B, when moisture-responsive element 130 is in an environment higher in moisture (which may be an air or soil environment), moisture-responsive element 130 tends to absorb moisture and expand in volume. As noted above, moisture- responsive element 130 is positioned and housed within internal chamber 122 such that it can only expand in the direction toward irrigation line 110. Thus, the expansion of moisture-responsive element 130 upon absorption of moisture is in the direction toward irrigation line 110, and causes the application of a local compressive force on irrigation line 110. The compressive force applied to irrigation line 110 restricts or completely stops the flow of liquid through irrigation line 110 via capillary action.

[0077] With reference back to FIGS. 3B-3C, in some embodiments, moisture- responsive irrigation device 100 comprises an optional bias screw 140 in lieu of cap 138.

[0078] Bias screw 140 is configured to threadedly engage with housing 120 such that an end portion of bias screw 140 can be advanced and retracted within internal chamber 122, so as to determine an initial position of moisture-responsive element 130 relative to irrigation line 110.

[0079] In some embodiments, bias screw 140 may comprise a handle or knob 145 configured for facilitating manual turning of bias screw 140. In some embodiments, bias screw 140 may be configured to threadedly engage with a top end of housing 120. Biasscrew 140 may thus be advanced and retracted relative to the top end of housing 120, by manually turning knob 145 clockwise or counterclockwise, respectively. In some embodiments, a bottom end of bias screw 140 acts as a stop which restricts an expansion of moisture-responsive element 130 toward to top end of housing 120. Thus, bias screw 140 may be configured to set and adjust an initial position of moisture-responsive element 130 within internal chamber 122.

[0080] For example, as can be seen in FIG. 3B, bias screw 140 may be turned clockwise to advance relative to a top end of housing 120. This causes a bottom end of bias screw 140 to apply a force which urges moisture -responsive element 130 toward irrigation line 110. In one example, an initial position of moisture -responsive element 130 within internal chamber 122 may be adjusted to apply no initial compressive force to irrigation line 110, wherein the flow of irrigation liquid in irrigation line 110 remains unrestricted. Conversely, as can be seen in FIG. 3C, bias screw 140 may be turned clockwise to advance relative to a top end of housing 120. This causes a bottom end of bias screw 140 to apply a force which urges moisture-responsive element 130 toward irrigation line 110. In this example, an initial position of moisture-responsive element 130 within internal chamber 122 may be adjusted to apply an initial compressive force to irrigation line 110, which partially restricts a flow of irrigation liquid in irrigation line 110.

[0081] With reference now to FIG. 3D, in some embodiments, device 100 comprises optional moisture transfer element 152 for communicating moisture from a desired location within soil environment 175 that is external to housing 120, to moisture- responsive element 130. As noted above, moisture -responsive element 130 may be generally in moisture communication with the ambient environment (which may be air and / or soil environment), via apertures 136 of housing 120. This allows moisture- responsive element 130 to absorb and desorb moisture from and to the ambient environment.

[0082] Generally, housing 120 may be located wholly or partially above-ground in the vicinity of plant 170, such that moisture-responsive element 130 is exposed to the air and / or ground-level soil environment. However, it may be desirable to expose moisture- responsive element 130 to moisture levels at a different location, such as root zone 172 of plant 170. This may be achieved via the use of moisture transfer element 152.

[0083] By way of explanation, the present invention is concerned with the problem of precise moisture-responsive releasing of irrigation water for a plant, based on the water actually available to plant 170. It is well known that the best measure of irrigation water available to a plant should be taken at the root zone of plant 170. Roots are the organs of a plant that take in water and nutrients into plant 170, which allows plants to grow taller and faster.

[0084] Thus, having an accurate indication of available hydration at the root zone (rather than at the ground level) is crucial for precise irrigation management. In order to allow moisture-responsive element 130 to react to moisture levels at the root zone of plant 170, it must be placed underground near the root zone.

[0085] However, it is also generally desirable to allow moisture -responsive element 130 to react with sufficient immediacy in response to changes in the measured hydration levels. Thus, when soil environment 175 loses moisture, it is desirable for moisture- responsive element 130 to desorb its moisture content quickly, to allow the restoration of the flow in irrigation line 110. However, in order to allow quick drying of moisture- responsive element 130 in response to reduced moisture, it must also have some exposure to ambient air, which in turn dictates placing housing 120 such that moisture-responsive element 130 is at least partially above ground.

[0086] Accordingly, device 100 uses the moisture transfer element 152 to allow placing moisture-responsive element 130 at least partially above-ground, while communicating to moisture-responsive element 130 the moisture levels found at the root zone of plant 170 (or another desired location not in the immediate vicinity of housing 120), rather than moisture levels at or near the surface of the soil.

[0087] Thus, moisture-responsive element 130 may react to the moisture levels from the root zone, communicated via moisture transfer element 152. When moisture transfer element 152 communicates higher levels of moisture at the root zone, moisture- responsive element 130 absorbs more moisture and expands in volume, thereby applying a local compressive force on irrigation line 110. The compressive force applied to irrigation line 110 restricts or completely stops the flow of liquid through irrigation line 110 via capillary action. Eventually, soil environment 175 near the root zone will dry out, wherein moisture transfer element 152 then does not communicate moisture to moisture-responsive element 130. This causes moisture-responsive element 130 todesorbs its stored moisture to the surrounding environment and to contract in volume, wherein it releases the force applied to irrigation line 110. Irrigation liquid flow is then restored in irrigation line 110, until the moisture levels in the soil rise again, wherein a new irrigation cycle begins.

[0088] In some embodiments, moisture transfer element 152 comprises an elongated wick or similar element. In some embodiments, a proximal end of moisture transfer element 152 is in moisture communication with internal chamber 122. For example, the proximal end of moisture transfer element 152 may be configured as a sleeve that fits around housing 120 such that it fully or partially covers apertures 136. In some cases, as can be seen in FIG. 3D, moisture transfer element 152 may be configured to fit within internal chamber 122, such that it is, directly or indirectly, in moisture communication with moisture-responsive element 130 housed within internal chamber 122, as shall be further described in detail herein below.

[0089] In some embodiments, moisture transfer element 152 is configured to transfer moisture along its length, from a distal end thereof which is located at a desired location within soil environment 175 outside of housing 120, to the proximal end thereof, which is in moisture communication with moisture-responsive element 130 inside internal chamber 122 (a further described in detail hereinbelow).

[0090] In some embodiments, moisture transfer element 152 ensures that moisture levels to which moisture-responsive element 130 is exposed reflect moisture levels at a desired location within soil environment 175, other than the immediate soil environment of device 100. This is achieved by communicating, through capillary action, the moisture level to which the distal end of moisture transfer element 152 is exposed, along its length, to its proximal end.

[0091] For example, in some embodiments, moisture transfer element 152 is configured as a wicking sleeve whose proximal end fits around the exterior, or within the interior (e.g., within internal chamber 122), of housing 120. The distal end of moisture transfer element 152 may then be positioned at any desired location within soil environment 175 externally to housing 120, e.g., at or near the root zone of plant 170. Thus, moisture transfer element 152 communicates, through capillary action, the moisture level to which the distal end of moisture transfer element 152 is exposed at the root zone, to its proximal end. As noted above, the proximal end of moisture transferelement 152 is in moisture communication with moisture -responsive element 130, and thus moisture-responsive element 130 can react to the moisture levels at the root zone of plant 170, rather than to those at the immediate vicinity of the device.

[0092] Moisture transfer element 152 may be made of a woven element, such as a sleeve or a rope made of fibers having desired wicking properties, such as manila hemp, hemp, cotton, polypropylene, polyester, aramid, or the like. In some embodiments, moisture transfer element 152 may be composed of a porous material, e.g., a sponge composed of polypropylene, polyether, polyester, cellulose, or the like. In certain embodiments, the moisture transfer element 152 is configured to mimic the moisture transfer characteristics of soil environment 175, such that moisture transfer element 152 transfers moisture at the same rate as moisture is being dispersed within soil environment 175. Thus, moisture transfer element ensures that moisture levels by the moisture- responsive element reflect moisture levels at a desired location within soil environment 175. Optionally, moisture transfer element 152 has a width or diameter within a range of 10 mm to 25 mm and a length of within a range of 3 cm and 10 cm.

[0093] In some embodiments, moisture transfer element 152 transfers water by capillary action. In some embodiments, the moisture transfer element comprises an absorbent material of a resilience that can hold absorbed water. In some embodiments, the moisture transfer element is a wick, cord, rope or the like, comprising strands of absorbent material. In some embodiments, the moisture transfer element is an artificial root. In some embodiments, moisture transfer element 152 mimics the capillary water transfer of a root. In some embodiments, moisture transfer element 152 comprises a rate of capillary action that is equal to or great than that of soil. In some embodiments, moisture transfer element 152 comprises a rate of capillary action that is greater than that of soil. Non-limiting examples of material that can transfer moisture through soil and function as moisture transfer element 152 include plastics and synthetics such as polymers (polypropylene, polyether, polyester and the like), nylon and polyester and natural materials such as cellulose, cotton and other fabrics. In some embodiments, moisture transfer element 152 is made of a polymer. In some embodiments, moisture transfer element 152 is made of plastic. In some embodiments, moisture transfer element 152 is a mesh of fibers.

[0094] FIG. 5A-5B show an optional irrigation plate 180, according to certain embodiments.

[0095] With reference back to FIGS . 1 A- 1C, in some embodiments, irrigation plate 180 may be disposed substantially beneath the roots 172, to be supplied with water for irrigating plant 170, e.g., via outlet 112 of irrigation line 110. As plate 180 fills up with water, moisture is absorbed by soil environment 175 from irrigation plate 180, water saturation of the soil increases and disperses upwards through soil environment 175, until it reaches near ground level, where device 100 is located. In certain embodiments, irrigation plate 180 may enable osmotic transference of moisture through soil environment 175 to roots 172 to provide plant 170 with the necessary water intake, without salts or minerals present in the water, which may be harmful to a plant’s longevity. In certain embodiments, the surface area of irrigation plate 180 may be dimensioned according to the size of roots 172 to ensure moisturizing of soil environment 175 adjacent to roots 172.

[0096] Irrigation plate 180 need not be inserted into the ground, but rather may be located at the bottom of a pot such as is used for potting plants. Indeed, irrigation plate 180 can be any water storing material or mechanism that stops water runoff. Irrigation plate 180 may be any water storage container that keeps the water deposited by system 100 from continuing down due to gravity, and rather allows for upward flow of the water through soil environment 175. Thus, irrigation plate 180 may be any container, tray, pot, nylon sheet, garden bed box, planter, or vessel that is below roots 172. Irrigation plate 180 may even be a non-dirt layer that is below soil environment 175. Many gardens, and parks are built over a layer of non-dirt construction material such as concrete or asphalt. In such cases this layer acts as the irrigation plate as it keeps water from continuing down and away from the roots via gravity.

[0097] In some embodiments, irrigation line 110 is configured to deposit water directly into plate 180. In some embodiments, irrigation line 110 is configured to deposit water proximal to plate 180. In some embodiments, proximal comprises within a distance of not more than 1, 2, 3, 5, 7, 10, 15 or 20 cm from a location. Each possibility represents a separate embodiment of the invention. In some embodiments, irrigation line 110 is configured to deposit water proximal to roots 172. In some embodiments, irrigation line 110 is configured to deposit water near an end of roots 172. In some embodiments, irrigation line 110 is configured to deposit water near the deepest end of roots 172. As water will begin to diffuse up from irrigation plate 180, and from the end of irrigation line 110, a skilled artisan will appreciate that both of these components can be ideallyplaces at the bottom of the root structure of plant 170. In some embodiments, plate 180 is proximal to roots 172. In some embodiments, plate 180 is proximal to an end of roots 172. In some embodiments, plate 180 is proximal to the deepest end of roots 172. In some embodiments, the end of the tube is not proximal to the housing element and / or the moisture-responsive element. In some embodiments, the end of the tube is at least 2, 3, 4, 5, 7, 10, 15, 20, 25 or 30 cm distance from the housing element or moisture-responsive element. Each possibility represents a separate embodiment of the invention.

[0098] Optionally, irrigation plate 180 is in a cube shape, a rectangular cuboid shape, a cylindrical shape, a hemispheric shape, or the like. In certain embodiments, where irrigation plate 180 is a cylinder, irrigation plate 180 may have a diameter within a range of 50-200 cm, which may provide an optimal surface area for water absorption by soil environment 175. Irrigation plate 180 may comprise a depth within a range of 10-500 mm for storing water and to prevent water spillage when water is received from irrigation line 110. Irrigation plate 180 may comprise a connector 181, configured to couple to moisture transfer element 152. In some embodiments, the irrigation plate is part of a plant potter, or a pot containing a plant.

[0099] In some embodiments, there is provided a method comprising providing a system of the invention, at least partially embedding housing 120 of the device in a soil environment at a predetermined depth adjacent to a plant, configuring the irrigation line to deliver water to a region of the soil environment below the plant, configuring a location of the moisture transfer element so as to provide moisture communication from the region of soil environment below the to the moisture-responsive element, and flowing water through the irrigation line.

[0100] In some embodiments, the housing is completely embedded in the soil environment. In some embodiments, the housing is partially embedded in the soil environment. In some embodiments, partial embedding comprises at least, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 cm of the housing embedded in the soil environment. Each possibility represents a separate embodiment of the invention. In some embodiments, the housing is partially embedded such that the moisture-responsive element contacts the air. In some embodiments, the housing is partially embedded such that moisture can is removed from the moisture-responsive element by evaporation. In some embodiments, partial embedding comprises contact between the moisture -responsive element and the air.

[0101] In some embodiments, the region of soil environment below the plant is at least 3, 5, 7, 9, 10, 12, 15, 17, or 20 cm from the moisture -responsive element. Each possibility represents a separate embodiment of the invention. In some embodiments, the region of soil environment below the plant is not proximal to the moisture-responsive element. In some embodiments, the outlet end of the tube is not proximal to the moisture-responsive element. In some embodiments, the irrigation plate is not proximal to the moisture- responsive element.

[0102] In some embodiments, the method further comprises placing an irrigation plate in the region of the soil environment below the plant. In some embodiments, the irrigation plate is embedded in the soil environment. In some embodiments, the irrigation plate is the bottom of a container holding the plant. In some embodiments, irrigation plate is placed such that the irrigation line can deliver water to the irrigation plate. In some embodiments, the device is connected to a water source, such as a faucet. In some embodiments, the irrigation line is connected at one end to the water source and the other end is positioned to deliver water to the region of soil environment under the plant. In some embodiments, the moisture transfer element provides moisture communication from the irrigation plate to the moisture-responsive element.

[0103] In some embodiments, egression of moisture from the moisture-responsive element reduces a constricting force applied on the irrigation line by the moisture- responsive element. In some embodiments, the reduction of the constricting force enables water flow through the irrigation line. In some embodiments, the water flow persists until sufficient water is delivered to the region of soil environment under the plant to cause moisture transfer via the moisture transfer element to the moisture-responsive element to again swell and close the irrigation line. In this way the device automatically regulates watering of the plant without any sensors or electronics and ensures the roots of the plant are never too wet and never too dry.

[0104] A skilled artisan will appreciate that a plant can be killed by both too little watering and too much watering. Too little watering and the plant dies of thirst; too much watering and the plant dies of strangulation as mud does not allow entry of air to the roots. Systems that only detect / measure / respond to moisture near the soil surface will often underestimate the amount of water available to roots. Due to proximity to the soil surface, heat from the sun, and evaporation by the air can produce soil with low moisture levels even when deeper soil is still wet. Further, water absorption by the plant can lowermoisture levels at higher soil levels, while the roots are still well watered. This can lead to over watering if the irrigation device is not responding to moisture levels at the bottom of the roots. The device and method of the invention employs the moisture transfer element to make sure that the plant is not killed by over watering, and provides an advantage over other irrigation devices known in the art. Further, because no electronics are used the device can be employed without outlets or the need for batteries or solar panels. Additionally, because the device responds to moisture directly at the plants roots, many systems can be inserted near many different plants with diverse water needs, and still irrigate each plant properly.

[0105] Throughout this application, various embodiments of this invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

[0106] Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases “ranging / ranges between” a first indicate number and a second indicate number and “ranging / ranges from” a first indicate number “to” a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween.

[0107] In the description and claims of the application, each of the words “comprise” “include” and “have”, and forms thereof, are not necessarily limited to members in a list with which the words may be associated. In addition, where there are inconsistencies between this application and any document incorporated by reference, it is hereby intended that the present application controls.

[0108] As used herein, the term "about" when combined with a value refers to plus and minus 10% of the reference value. For example, a length of about 1000 nanometers (nm) refers to a length of 1000 nm+- 100 nm.

[0109] It is noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a polynucleotide" includes a plurality of such polynucleotides and reference to "the polypeptide" includes reference to one or more polypeptides and equivalents thereof known to those skilled in the art, and so forth. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only" and the like in connection with the recitation of claim elements or use of a "negative" limitation.

[0110] In those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase " A or B " will be understood to include the possibilities of "A" or "B" or "A and B."

[0111] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. All combinations of the embodiments pertaining to the invention are specifically embraced by the present invention and are disclosed herein just as if each and every combination was individually and explicitly disclosed. In addition, all sub-combinations of the various embodiments and elements thereof are also specifically embraced by the present invention and are disclosed herein just as if each and every such sub-combination was individually and explicitly disclosed herein.

[0112] Additional objects, advantages, and novel features of the present invention will become apparent to one ordinarily skilled in the art upon examination of the following examples, which are not intended to be limiting. Additionally, each of the various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below finds experimental support in the following examples, and these examples found hereinbelow should be considered as embodiments of the present invention.

[0113] Various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below find experimental support in the following examples.

[0114] Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A moisture-responsive irrigation device comprising: a housing defining an internal chamber and configured to be positioned in the vicinity of a plant to be irrigated within a soil environment; an irrigation line passing transversely through said internal chamber and having an inlet end connected to a source of irrigation water and an outlet extending outside of said housing, wherein said irrigation line is configured to transport irrigation liquid at least partially via capillary action or absorbency; and a moisture-responsive element enclosed within said internal chamber, wherein said moisture-responsive element is configured to expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing moisture, wherein said moisture-responsive element is enclosed within said internal chamber such that said expanding causes said moisture-responsive element to apply a compressive force to said irrigation line, and said contracting releases said compressive force, and wherein said irrigation line is configured such that said application of said compressive force restricts a flow of said irrigation liquid along said irrigation line, and said release of said compressive force restores said flow.

2. The device of claim 1, wherein said irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, without pressurization.

3. The device of claim 1, wherein said irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, under at least a partial influence of gravity.

4. The device of any one of claims 1-3, wherein said source of irrigation water is a reservoir, and wherein said inlet end is dipped in said reservoir.

5. The device of claim 4, wherein said reservoir is elevated relative to said soil environment.

6. The device of any one of claims 1-5, wherein said expanding of said moisture- responsive element is proportional to an amount of said absorbing, wherein said applying of said compressive force is proportional to said expanding, and wherein said restricting of said flow is proportional to said applying of said compressive force.

7. The device of any one of claims 1-6, wherein the housing comprises at least one aperture configured to provide air and moisture communication between said moisture- responsive element and the ambient environment outside said housing.

8. The device of claim 7, wherein said housing is configured to be positioned such that said at least one aperture is at least partially above-ground.

9. The device of any one of claims 1-8, further comprising a moisture transfer element configured to communicate moisture along its length, wherein a proximal end of said moisture transfer element is in moisture communication with said moisture- responsive element, and wherein a distal end of said moisture transfer element is configured to be located at a desired location within said soil environment10. The device of claim 9, wherein said desired location is other than the immediate soil environment vicinity of said housing.

11. The device of claim 10, wherein said desired location is near the root zone of said plant.

12. The device of any one of claims 1-11, further comprising a stake portion extending from a bottom of said housing and configured for inserting into the ground.

13. The device of any one of claims 1-12, further comprising a rigid element coupled to a bottom end of said moisture-responsive element, wherein said rigid element is configured to communicate said compressive force from said moisture-responsive element to said irrigation line.

14. The device of any one of claims 1-13, wherein said moisture-responsive element is enclosed within said internal chamber such that said expanding is only possible in the direction of said irrigation line.

15. The device of any one of claims 1-14, further comprising a bias screw configured to threadedly engage with said housing such that an end portion of said bias screw can be advanced and retracted within said internal chamber so as to determine an initial position of said moisture-responsive element relative to said irrigation line.

16. A method for moisture-responsive irrigation, comprising: providing a device comprising: a housing defining an internal chamber, an irrigation line passing transversely through said internal chamber and having an inlet end configured to be connected to a source of irrigation water and an outlet extending outside of said housing, wherein said irrigation line is configured to transport irrigation liquid at least partially via capillary action or absorbency; and a moisture-responsive element enclosed within said internal chamber, wherein said moisture -responsive element is configured to expand in volume in response to absorbing moisture, and to contract in volume in response to desorbing moisture, wherein said moisture-responsive element is enclosed within said internal chamber such that said expanding causes said moisture-responsive element to apply a compressive force to said irrigation line, and said contracting releases said compressive force, and wherein said irrigation line is configured such that said application of said compressive force restricts a flow of said irrigation liquid along said irrigation line, and said release of said compressive force restores said flow; positioning said device in the vicinity of a plant to be irrigated within a soil environment, such that said outlet is positioned to irrigate said plant; and connecting said inlet end to a source of irrigation water.

17. The method of claim 16, wherein said irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, without pressurization.

18. The method of claim 16, wherein said irrigation line comprises any medium configured to transport an irrigation liquid by capillary action or absorbency, under at least a partial influence of gravity.

19. The method of any one of claims 16-18, wherein said source of irrigation water is a reservoir, and wherein said connecting comprises dipping said inlet end in said reservoir.

20. The method of claim 19, further comprising elevating said reservoir relative to said soil environment.

21. The method of any one of claims 16-20, wherein said expanding of said moisture- responsive element is proportional to an amount of said absorbing, wherein said applying of said compressive force is proportional to said expanding, and wherein said restricting of said flow is proportional to said applying of said compressive force.

22. The method of any one of claims 16-21, wherein the housing comprises at least one aperture configured to provide air and moisture communication between said moisture-responsive element and the ambient environment outside said housing.

23. The method of claim 22, further comprising positioning said device such that said at least one aperture is at least partially above-ground.

24. The method of any one of claims 16-23, wherein said device further comprises a moisture transfer element configured to communicate moisture along its length, wherein a proximal end of said moisture transfer element is in moisture communication with said moisture-responsive element, and wherein a distal end of said moisture transfer element is configured to be located at a desired location within said soil environment25. The method of claim 24, further comprising locating said distal end of said moisture transfer element in a location other than the immediate soil environment vicinity of said housing.

26. The method of claim 25, further comprising locating said distal end of said moisture transfer element is near the root zone of said plant.

27. The method of any one of claims 16-26, wherein said device further comprises a stake portion extending from a bottom of said housing and configured for inserting into the ground.

28. The method of any one of claims 16-27, wherein said device further comprises a rigid element coupled to a bottom end of said moisture -responsive element, and wherein said rigid element is configured to communicate said compressive force from said moisture-responsive element to said irrigation line.

29. The method of any one of claims 16-28, wherein said moisture-responsive element is enclosed within said internal chamber such that said expanding is only possible in the direction of said irrigation line.

30. The method of any one of claims 16-29, wherein said device further comprises a bias screw configured to threadedly engage with said housing such that an end portion of said bias screw can be advanced and retracted within said internal chamber so as to determine an initial position of said moisture-responsive element relative to said irrigation line.

Images