Abstract:
An irrigation/fertilization filter apparatus for continuously supplying liquid to plants and trees, which comprises a reservoir for containing the liquid having a single exit aperture on its bottom; a cover releasably fitted to the reservoir, which may be adapted with a hose attachment for connection to an external water source; an inlet control for regulating the amount of liquid entering the reservoir; and an outlet control for regulating the rate at which liquid exits the reservoir. The outlet control is situated within the reservoir and consists of a layer of particulate matter, a durable primary filter member, and a porous support, which sits directly on the reservoir&#39;s bottom.

Description:
BACKGROUND OF THE INVENTION 
     1. Field Of The Invention 
     Disclosed is a drip irrigation/fertilization filter apparatus for watering and fertilizing plants and trees with a generally continuous flow of liquid rather than an applied pool of water. The disclosed apparatus comprises a portable stabilized reservoir having an automatic filling system, internal filtration system, and a passive drip delivery means. 
     The device of the present invention improves upon the related art by preventing internal algae growth on the primary filter element and corresponding clogging due to light entry into the reservoir. The present invention also improves upon the related art by disclosing a novel primary filter element, which is more durable, versatile, and effective than traditional filters. In addition, the present invention improves upon the related art by allowing for use in extremely muddy conditions, and at the same time extending the time period between required filter changes. The present invention also improves upon the related art by permitting a user to employ an easily constructed, relatively inexpensive, and effective way to water plants and trees with a virtually continuous flow of filtered water and fertilizer and at the same time conserve water. Additionally, the present invention improves upon the related art by disclosing a design adapted to sit directly atop soil near plants or trees to be watered, which obviates the need for a support base, spikes, or other means for supporting the reservoir. 
     2. Description of the Related Art 
     Various drip irrigation filter devices have been previously developed. These devices lack an effective means for diminishing light entry into the liquid reservoir, and corresponding algae growth and clogging on the primary filter element. Also, known irrigation filter devices are not equipped for use with muddy water, such as that found in irrigation ditches and other agricultural settings, and are designed primarily for use with individually potted plants rather than plants and trees situated directly in the ground. 
     U.S. Pat. No. 5,383,601 discloses a drip watering apparatus. The apparatus includes a reservoir having a bottom surface with a plurality of apertures, and a base for supporting and stabilizing the reservoir. The reservoir cover can be adapted with a perimeter overhang, which helps shade the reservoir from direct sun exposure. The disclosed apparatus also includes an outlet control system, comprising a support member formed from rigid material and having a plurality of apertures. Spacers are used to elevate the support member above the reservoir bottom. A filter sheet, made from materials such as cloth, paper products, and natural or synthetic polymers, is positioned atop the support member, and a layer of particulate matter rests directly atop the filter. The disclosed liquid inlet control system comprises a float, which is connected to an inlet/cut-off valve via a connecting arm. Liquid, which is added to the reservoir either manually or through a hose attachment, rests above the layer of particulate matter. As the float is forced upward by incoming liquid, the inlet/cut-off valve is adjusted to stop the water flow. As the water level decreases during the irrigation process, the float lowers and activates the inlet/ cut-off valve to allow more liquid into the reservoir. 
     U.S. Pat. No. 4,527,353 discloses an irrigation/fertilization control and distribution system. The system includes separate water valve and fertilization mechanisms. The water valve mechanism consists of a water reservoir, which is open to atmospheric pressure and is connected to a sealed water chamber. When the ambient temperature exceeds a predetermined level, air expansion forces water out of the chamber and into the water reservoir, and simultaneously opens a valve allowing pressurized water to flow through a water distribution network and ultimately to plants situated in a connected hydrophonic growth conduit. As atmospheric pressure increases, the valve is closed, and water supply to the distribution network is terminated. 
     U.S. Pat. No. 5,117,582 discloses a tree irrigator comprising a tree trunk encircling container, which includes an inner water container and an outer support container. The inner water container bottom has a water exit hole, and the outer support container bottom has holes for delivering water to the encircled tree. Between the inner and outer containers are a support pad, spacers, and a wire mesh for aiding in structural support and drainage. 
     U.S. Pat. No. 5,212,905 discloses a plant watering device comprising a self-contained cylindrical reservoir that surrounds a plant. The device contains an adjustable drip valve means in fluid communication with the reservoir that delivers water or nutrients dropwise to the plant. 
     U.S. Pat. No. 2,375,860 discloses an irrigation appliance having a combined support and water delivery hollow spike. The spike is inserted into the ground to be watered. Water is held in an upper first container and percolated into a lower second container having fertilizer. The fertilizer solution then exits into the spike and, via apertures in the distal end of the spike, escapes from the device to water the ground near the plant. 
     U.S. Pat. No. 3,026,827 discloses a plant watering and feeding device having a perforated spike that is inserted into the ground for delivering water. Included is a plant food container and associated valves for selectively extracting the food into the delivered water. 
     U.S. Pat. No. 3,856,205 discloses a siphon type plant watering device with an attached hollow spike that is inserted into the ground to be watered and controls additional water delivery. When the ground becomes dry, the hollow spike communicates this condition to the apparatus by allowing air to pass into a controlling system that then delivers water to the ground, and subsequently turns water delivery off when the ground is wet, thus blocking air passage into the controlling system. 
     U.S. Pat. No. 4,231,188 discloses a method and system for propagating plants housed in individual containers. The bottom side of individual plant containers are adapted with porous prongs, which pierce an irrigation tray support containing a sand layer sandwiched between a top and bottom water impermeable plastic opaque sheet. Water from the irrigation tray support passes up through the prongs and into the plant container via capillary action. The disclosed plant container covers holes resulting from each prong, which prevents light entry into the system and corresponding algae growth. The system may employ a conventional filter. 
     U.S. Pat. No. 3,168,224 is a drip feed device, which is designed to be clipped to the rim of a soil containing pot. Water is delivered from a reservoir container into a tile basin, via an adjustable drip valve. When the tilt basin is filled, it tips and applies water to the soil. 
     U.S. Pat. No. 4,908,986 discloses a plant fertilizing and watering device for fertilizing and watering individually potted plants. The primary component of this invention is a disk made of synthetic resin or foam, which has a centrally located recess that holds fertilizer and is covered by a porous plug made of the disk material. The disk containing fertilizer is placed in a potted plant&#39;s reservoir and covered with water, after which the pot containing the plant is watered periodically. Water and fertilizer pass through the disk&#39;s plug via a hole in the bottom of the plant pot by capillary action. 
     U.S. Pat. No. 5,189,835 discloses a device for continuously irrigating soil of plants growing in individual pots. The device&#39;s primary components include a wooden or styrofoam block, which is wrapped in a plastic tape layer having a single sand layer adhesively attached to the tape&#39;s inner surface. The block and tape assembly is placed in a shallow container of water, and an individually potted plant is placed atop the block&#39;s upper surface in contact with the tape layer, so that the internal sand layer facilitates capillary water flow to and from the potted plant. 
     U.S. Pat. No. 2,231,300 discloses an irrigating flowerpot made of porous material and a mesh covered bottom, which can be placed within a water containing receptacle or planted directly into the ground. Water and nutrients pass through the flowerpot&#39;s porous walls by capillary action to facilitate constant irrigation and fertilization. This device is designed for growing individually potted plants. 
     U.S. Pat. No. 5,181,951 discloses a gravel/fertilizer packet for potted plants. A water permeable fertilizer packet is placed in the bottom of planting pots to aid in feeding individually potted plants and in preventing soil loss through a pot&#39;s drain hole. 
     U.S. Pat. No. 5,252,302 discloses a liquid fertilizer apparatus utilizing a container that holds a porous sack of nutrients. Water is manually introduced into the container and then allowed to exit slowly through an adjustable valve and onto a plant. 
     As is apparent from this brief review of related art, known irrigation/filtration devices are not designed to provide an efficient means for continuously hydrating ground based plants and trees, while simultaneously diminishing light entry into the reservoir and corresponding algae growth and clogging on the primary filter element. Moreover, known irrigation/filtration devices do not employ an optimally durable and versatile filter element, and consequently are not equipped for effective use in circumstances involving relatively muddy water, such as in irrigation ditches and similar agricultural settings. Also, known irrigation/filtration devices do not employ a means for promoting plant growth by optimizing fluid delivery to plants while at the same time promoting water conservation. Thus, a need exists for an irrigation/filtration device that: prevents internal algae growth and filter clogging associated with light exposure; dramatically reduces the inconvenience and expense associated with frequent filter changes due to algae growth and clogging; facilitates use in irrigation ditches and other circumstances involving muddy water; promotes irrigation efficiency by optimizing hydration and promoting water conservation; and avoids sizable costs and expenses associated with elaborately designed manual and mechanized irrigation devices. 
     SUMMARY OF THE INVENTION 
     Disclosed is a drip irrigation/fertilization filter apparatus for supplying a liquid, usually water or water and a combination of nutrients and fertilizer, to a plant or tree situated directly in the ground. The subject apparatus comprises a reservoir for containing the liquid having a side wall, an upper rim, and a bottom having a single centrally located aperture. The reservoir is made from water insoluble materials such as natural or synthetic polymers and has an optional externally attached handle for easy portability. During use, the reservoir is positioned directly on the ground or soil in close proximity to the tree or plant to be watered. 
     Provided in the subject apparatus is a liquid outlet control means for regulating an amount of outgoing liquid from the reservoir. The outlet control means comprises a porous support member, a primary filter element, and a bed of particulate matter. 
     The porous support member sits within the reservoir directly on the reservoir bottom, and is made from a mixture of large grain sand and a binding material such as Portland cement or a resin. In addition to acting as a filter means, the porous support member acts as a ballast by stabilizing and securing the disclosed apparatus in place during use. 
     Sealed atop the porous support member is a 3-piece circularly shaped primary filter member comprising an outer edge and a top and bottom layer, between which is sealed a nylon coated, decay resistant filter screen. The top and bottom primary filter member layers are made of plastic and contain a plurality of aligned, peripherally located apertures. 
     The primary filter member bottom layer contains a series of grooved channels, which are directed toward a single aperture located in the center of the bottom layer. The decay resistant filter screen sits directly atop the bottom layer, and the ring shaped top layer is positioned directly atop the decay resistant screen. Silicon, metal pins, or any other suitable attachment means are placed in the aligned, peripherally located plurality of apertures to seal the 3-piece primary filter member unit together. Silicon or any other suitable sealing means is placed around the primary filter member outer edge to seal the primary filter member to the reservoir&#39;s inside wall, which facilitates effective liquid flow by directing liquid to pass through the primary filter member and not around its edges. 
     A layer of loose sand is positioned directly atop the 3-piece primary filter element. Liquid being used for irrigation and fertilization rests directly above the loose sand layer. 
     Also provided in the subject apparatus is a liquid inlet control means comprising a float, a connecting arm, and an inlet/shut-off valve. The inlet control means is situated inside the reservoir and is attached to the bottom of the reservoir cover. A hose attachment means is secured atop the reservoir cover, and consists of a pipe connected at one end to the inlet/shut-off valve, and connected at the other end to an external hose or other water source. The reservoir cover is releasably fitted to the reservoir upper rim, and can be adapted to incorporate an overhang extending beyond the reservoir side wall to help shade the reservoir from direct sun exposure. 
     In function, as incoming liquid forces the float upward, the inlet/shut-off valve is adjusted to diminish, and eventually stop, liquid entry into the reservoir. Once in the reservoir, liquid passes first though the loose sand layer, which traps particulate matter and allows the filtered liquid to pass onto the primary filter element and over the decay resistant screen. The decay resistant screen then traps additional particulate matter and allows filtered liquid to enter grooved channels located on the primary filter element bottom layer, which direct liquid to the single centrally located aperture on the primary filter element bottom layer. Liquid exiting the primary filter element bottom layer passes through the porous support element, which further traps particulate matter, and exits the reservoir via the single centrally located aperture on the reservoir&#39;s bottom surface. As the liquid level in the reservoir falls during the irrigation process, the float lowers which activates the inlet/cut-off means to deliver more liquid into the reservoir. 
     An object of the present invention is to provide a means for drip irrigating and fertilizing plants and trees. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus that includes means for preventing light entry into the liquid reservoir and means for shading the reservoir from direct sun exposure. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus designed to prevent clogging associated with algae growth on the primary filter element. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus employing a durable and versatile filter element, which optimizes filtration and does not require frequent changing. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus capable of filtering muddy water, such as that associated with irrigation ditches, without compromising the integrity or functionality of the apparatus, and without requiring frequent filter changes. 
     Another object of the present invention is to provide a drip irrigation/fertilization filter apparatus having a means for leveling and stabilizing the apparatus directly on the ground proximate a plant or tree to be watered, thus obviating the need for a separate reservoir support base. 
     Another object of the present invention is to supply, for increased growth, a means for conserving water and simultaneously suppling continuous hydration to plants and trees. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus that has an adjustable outlet flow of liquid. 
     Another object of the present invention is to furnish a drip irrigation/fertilization filter apparatus having an easily portable reservoir, an adjustable inlet and outlet flow, and a means for including fertilizer during irrigation. 
     Another object of the present invention is to disclose a drip irrigation/fertilization filter apparatus that is inexpensive and reliable for delivering a continuous flow of liquid to plants and trees. 
     Other objects, advantages, and novel features of the present invention will become apparent from the detailed description that follows, when considered in conjunction with the associated drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross sectional partially exploded view of the disclosed device. 
     FIG. 2 is a bottom view of the porous ballast support member. 
     FIG. 3 is a top view of the porous ballast support member. 
     FIG. 4 is a bottom view of the primary filter member bottom portion. 
     FIG. 5 is a top view of the primary filter member bottom portion. 
     FIG. 6 is a top view of the filter screen. 
     FIG. 7 is a top view of the primary filter member top portion. 
     FIG. 8 is an exploded perspective view showing the 3-piece primary filter member assembly of the present invention. 
     FIG. 9 is a cross sectional view of the cover of the present invention. 
     FIG. 10 is a cross sectional view of an alternative embodiment of the cover of the present invention. 
     FIG. 11 is a side view of the primary filter member with a portion shown in cutaway. 
     FIG. 12 is a cross sectional view of the disclosed device. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now specifically to the drawings, FIG. 1 shows the inventive drip irrigation/fertilization filter, which is generally designated herein with the reference numeral  10 . Irrigation filter  10  is comprised of a reservoir  12 , a liquid outlet control means, and a liquid inlet control means. 
     As shown in FIG. 1, reservoir  12  comprises a side wall  20  that is generally continuous and often a slightly tapered cylinder, although other configurations, shapes and sizes of reservoir  12  are contemplated to be within the realm of this disclosure. The side wall terminates in an upper rim  22  and a bottom  24 . For portability, an optional handle  26  is often included, which is connected to the outside of side wall  20  by standard means. 
     Formed into the reservoir&#39;s bottom  24  is a single aperture  28 , the diameter of which is variable and selected to accommodate the particular reservoir volume and desired delivery rate. The diameter of aperture  28  is often between about one-half inch to one-eighth inch, but may be smaller or larger if needed. The aperture may be directly formed in reservoir bottom  24  during fabrication or later by drilling, punching, melting, and equivalent methods. Although not mandatory, preferably reservoir  12  is formed as a single unit with rim  22 , bottom  24 , and side wall  20  connected into a seamless piece. Reservoir  12  is fabricated from water insoluble material such as natural or synthetic polymers, and non-corrosive metals and metal alloys. Traditionally shaped buckets, inexpensive or discarded plastic pails, or more aesthetically pleasing containers are all suitable for serving as a reservoir for the present invention. 
     The liquid outlet means comprises a porous support member  14 , a 3-piece primary filter member  16 , and layer of particulate matter  17 . As shown in FIGS. 2 and 3, porous support member  14  has a top surface  13 , a bottom surface  15 , a perimeter edge, and is generally planar in shape, although other shapes, such as concave and convex, are contemplated. Typically, porous support member  14  is approximately 21 to 22 inches in diameter, and approximately 1¼ inches thick, although different sizes are contemplated depending upon the size of reservoir  12 . As shown in FIGS. 1,  2 , and  3 , porous support member top surface  13  has a centrally located recess, which is approximately 3 inches in diameter and {fraction (1/16)} inch deep. Porous support member bottom surface  15  has a centrally located recess, which is approximately 6 inches in diameter and one-half inch in depth. Porous support member  14  is sized to fit within reservoir  12 , proximate reservoir bottom  24 , and is positioned within reservoir  12  directly on top surface  23  of reservoir bottom  24 . Porous support member  14  is typically made from a mixture of #6 large grain sand and a binding material such as Portland cement or a resin. 
     Primary filter member  16  comprises a top portion  30 , a bottom portion  32 , and a filter screen  34 . As shown in FIGS. 4 and 5, bottom surface  42  and top surface  36  of bottom portion  32  contain a plurality of grooved channels  38 , which are directed toward a single aperture  40  located in the center of bottom portion  32 . As shown in FIGS. 4,  5 ,  7  and  8 , bottom portion  32  and top portion  30  contain a plurality of aligned, hexagonally shaped, peripherally located apertures  44 , and peripherally located spacers  46 . As shown in FIGS. 6 and 8, filter screen  34  contains a plurality of apertures  48 . Apertures  40  and  44  are approximately ¼ inch in diameter, although different sizes are anticipated depending upon constructions preferences. As shown in FIG. 1, bottom surface  42  of bottom portion  32  sits directly atop porous support member top surface  13 . Filter screen  34  sits directly atop top surface  36  of bottom portion  32 . Top portion  30  sits directly atop filter screen  34 . As shown in FIGS. 8,  11 , and  12  the  3 -piece assembly, comprising bottom portion  32 , filter screen  34 , and top portion  30 , is sealed into one unit by inserting attachment means  50  into aligned, hexagonally shaped, peripherally located plurality of apertures  44  and snapping the  3 -piece primary filter member unit together. Silicone or some other suitable sealant  51  is placed around the outer edge of primary filter member  16  to attach primary filter member  16  to the inside of reservoir side wall  20 . Bottom portion  32  and top portion  30  are made of plastic, and filter screen  34  is made of a nylon-coated, decay-resistant synthetic or natural polymer material. The thickness of filter screen  34  and the type of material from which filter screen  34  is fabricated are selected to permit a desired liquid flow rate. 
     As shown in FIG. 1, layer of particulate matter  17  sits directly atop primary filter member  16 . Typically, layer  17  is comprised of loose #8 sand, gravel, and the like, which are selected for their ability to pass a desired amount of liquid in a given period of time. Particle size within particulate matter  17  and interactive characteristics between the particles within the particulate matter determines the liquid flow rate. The size of the particles comprising the particulate matter are selected to have a size too large to pass through underlying primary filter member  16 . Generally, for any one type of particulate matter  17 , the thicker the layer of particulate matter  17 , the slower the passage of liquid. Depending upon the desired liquid flow rate, the thickness of layer  17  is varied. Layer  17  must have a compositional structure that permits the flow of liquid but prevents the passage of particulate matter  17 . 
     As shown in FIG. 9, the preferred embodiment of the liquid inlet control means comprises float  51 , connecting arm  52 , and inlet/shut-off valve  54 . Cover  18  comprises bottom surface  60  and top surface  62 . Attached to bottom surface  60  and extending through top surface  62  is valve  54 . One end of connecting arm  52  engages valve  54 , while the opposite end of connecting arm  52  is attached to float  51 . Optionally attached to top surface  62  is pipe attachment  56 , which can be connected at one end to valve  54  and terminate in hose fitting  58 . Hose fitting  58  may be connected to an external liquid source. Alternatively, liquid may be added to reservoir  12 , manually. Cover  18  may also be adapted to include a perimeter overhang  21  extending beyond reservoir side wall  20  to help shade reservoir  12  and its contents from direct sun exposure. Cover  18  and float  51  are made of plastic. Connecting arm  52 , pipe attachment  56 , and hose fitting  58  are made of rust resistant metals or metal alloys. 
     As shown in FIG. 10, an additional embodiment of the inlet control means comprises float  51   a,  connecting stem  52   a,  and inlet/shut-off value  54   a . Cover  18   a  comprises outer surface  62   a  and inner surface  60   a.  Outer surface  62   a  is cone shaped and terminates in peak  64 . Attached at peak  64  is inlet/shut-off valve  54   a.  One end of connecting stem  52   a  engages inlet/shut-off valve  54   a,  while the opposite end of connecting stem  52   a  is attached to float  51   a.  A standard garden hose or other external water source may be attached to inlet/shut-off valve  54   a  at peak  64 . 
     In function, the subject device is often used in tree orchards, or similar agricultural environments, which require the watering and fertilization of multiple trees or plants. However, the alternative embodiment of the inlet control means, along with a smaller reservoir, may be more aesthetically pleasing and suitable for use with home gardens, commercial and public landscapes, and other non-agricultural settings. 
     Generally, an individual device is placed directly on the soil near the base of each tree or plant, and in any available shade. Although water may be added to each device manually, usually in practice each device is directly connected to a water hose or pipe, which is equipped with a timer or an equivalent means for regulating the periods in which water is supplied to the hose. During periods in which water is supplied to the hose, the reservoir fills to the cut-off level and is maintained at that level via the inlet/shut-off valve. About a 45 minute filling cycle is common, but other time intervals are acceptable and depend on various factors, including plant type, soil type, and reservoir volume. The liquid within the reservoir percolates down through the particulate layer, through the primary filter member and support member, and out of the single aperture on the reservoir bottom. To increase or decrease liquid delivery, the type or thickness of filter screen and particulate matter can be adjusted. Fertilizer and other nutrients may be placed either directly within the reservoir or, more commonly, directly beneath the reservoir. The stream of exiting drips slowly dissolves the nutrients for transportation into the soil and plant or tree roots. 
     Several advantages result from the disclosed device. Most significantly, algae is less likely to grow on the decay resistant screen because employing layers of particulate matter both above and below the primary filter member prevents light from penetrating the primary filter member. Moreover, the porous support member sits directly on the reservoir&#39;s bottom, as opposed to being elevated by spacers, which further impedes light entry into the reservoir. In addition, the reservoir&#39;s bottom contains only one exit aperture, instead of a plurality of exit apertures, thus diminishing the number of potential light entry points. Also, the reservoir cover may be adapted with a perimeter overhang, which assists in preventing light entry into the reservoir. 
     The primary filter member is more durable than conventional filters, and is better equipped for use in a variety of agricultural and commercial growing settings, including muddy irrigation ditches. Using the decay resistant filter screen instead of conventional paper or cloth filters enables the device to filter very muddy water for long time periods between filter cleanings and changes. Sealing the primary filter member to the reservoir&#39;s inside wall prevents unfiltered liquid from leaking through the device onto soil. 
     The present invention also promotes water conservation while effectively hydrating tree and plant roots by dripping liquid, which may be regulated to achieve varying volume delivery rates, one droplet at a time, through the reservoir&#39;s one centrally located aperture, which subsequently fans out and hydrates all roots efficiently. This hydration method avoids water waste associated with evaporation and the inadvertent watering of weeds and nearby objects that do not require watering. And finally, the heavy porous support member acts not only as a filter, but also as a ballast by stabilizing the reservoir and its contents, which obviates the need for a stand or other apparatus to hold the reservoir in place during use. Also, given the disclosed configuration of the subject invention, it is easily transported and disassembled for cleaning, and is relatively inexpensive in construction. 
     The foregoing detailed disclosure of the inventive irrigation/fertilization filter apparatus  10  is only illustrative of the preferred embodiment of the invention, and is not a limitation upon the invention&#39;s scope. Those skilled in the art will envision many other possible variations of the structure disclosed herein, which nonetheless fall within the scope of the following claims. For example, reservoir  12  and its contents may be larger or smaller to accommodate different liquid volumes, and constructed in different shapes and sizes depending upon placement requirements. Consequently, the scope of the present invention should be determined with reference to the appended claims, and not by the examples that have been given herein.