Growth tray

Abstract

A growing tray (300,400) comprising a perimeter wall (302,402) and a base (301,401). The base (301,401) comprises irrigation openings (303,403) extending therethrough for allowing fluid to pass into and out of the growing tray (300,400). The base (301,401) is coupleable to a conduit to allow fluid communication between the conduit and the base (301,401) via the irrigation openings (303,403).

Description

[Technical field]

[0001] FIELD OF THEINVENTION The present invention relates to growing trays for containing growing crops, and in particular to growing trays for use in agricultural systems such as hydroponic agricultural systems. [Background technology]

[0002] Historically, systems and methods for growing crops have required large areas of land and have had to be located in locations with the appropriate climate for the crops to grow effectively.

[0003] Indoor farming under artificial light has gained popularity for many crops, and there are many advantages associated with indoor farming, such as reduced need for water, fertilizer, and pesticides, as well as increased control over the taste, texture, and other characteristics of the crop.

[0004] More recently, advanced agricultural techniques such as hydroponic, aeroponic and other such growing systems have provided the ability to grow high quality crops indoors with very advanced utilization of light, water, and fertilizer.

[0005] A commercially viable indoor farming solution requires maximizing the efficient use of space and other resources such as lighting, fluids, and labor.

[0006] Currently, short plants, mainly herbs and leafy greens, are grown indoors under artificial light.

[0007] An example of an indoor farm is disclosed in WO202030825A1. Seeds are pre-treated and germinated in "high care" portions to reduce contamination during germination. The seedlings are then moved through the growth chamber in a support vehicle that houses growth trays that move along frames as the crops grow and until they are ready to be harvested. The system includes lighting above each growth station and a recirculating irrigation system to provide nutrients to the growing crops. The irrigation system uses tap water mixed with nutrients, which is pumped to the growing crops. Water draining from the racks is reintroduced into the water mixture to minimize wastewater.

[0008] WO '825 describes an apparatus for use in a hydroponic growing system. The apparatus is located within a high care facility within the hydroponic growing system. The apparatus comprises a frame of vertical members 103 and horizontal members 104 supporting a horizontal track or guideway to which a set of growing vehicles are attached. The growing vehicles each house a number of growing trays in which plants or crops are housed during growth.

[0009] In WO'825, the size of the facility is limited by the size of the building and the frames therein. Temperature, humidity, and air speed are controlled in high care facilities. The environment is substantially the same for each growing tray. Therefore, typically the same crop or type of crop is grown in each truck. In the configuration described in WO'825, it is only possible to access the trays sequentially from each truck or guideway. A mechanical failure of a truck can render a large portion of the facility inaccessible until repaired.

[0010] The present invention aims to further develop indoor growing, vertical or controlled environment agriculture systems and methods. In particular, the present invention aims to further develop technology in hydroponic growing systems that allow for more efficient use of water, reduced piping, and more precise control of the water delivered to each crop.

[0011] It should be appreciated that the present invention also aims to maximize yields and improve efficiencies with respect to the use of assets, resources, and services required by crops. These efficiencies may comprise, for example, reduced water requirements, reduced fertilizer and pesticide requirements, increased control over taste, increased control over the texture and other characteristics of the crop, efficiencies in the use of artificial lighting, efficiencies in the maintenance of facilities, improved space utilization, improved safety, increased automation, and a corresponding reduction in labor. Overall, the present invention aims to address the problem of enabling more growth in a smaller space with less power consumption, less capital expenditure, less maintenance, and less labor costs.

[0012] Furthermore, the benefits from controlled environment or vertical farming systems are likely to become more pronounced as improved infrastructure components, such as more efficient and cheaper lighting, and cheaper electricity, become available. Summary of the Invention

[0013] The invention is defined in the accompanying claims.

[0014] Agriculture System An agricultural system is provided comprising a support structure including a tray-receiving location for receiving a growth tray, and an irrigation system for supplying fluid to and draining fluid from the tray-receiving location. The irrigation system includes a tray conduit coupleable to a bottom of the growth tray when positioned in the tray-receiving location to enable fluid communication between the tray conduit and the growth tray via irrigation openings extending through a base of the growth tray. The irrigation system is configured to supply fluid to and drain fluid from the growth tray via the tray conduit.

[0015] The agricultural system may be an indoor agricultural system.The agricultural system may be a hydroponic agricultural system.

[0016] The fluids used in agricultural systems may be liquids or liquid solutions, for example water with dissolved nutrients or other substances for crop growth. Hereinafter, the term "water" includes water with dissolved nutrients or other substances.

[0017] By filling the growth trays bottom-up, the amount of water delivered to the growth trays and the period of time the growth trays contain fluid can be more precisely controlled compared to, for example, top-down irrigation systems. As a result, water can be used more efficiently and the growth of the crops contained in the growth trays can be more optimally controlled. Additionally, the amount of piping in the irrigation system can be minimized since the same conduits can be used to deliver and drain water.

[0018] The irrigation system may further comprise a branch conduit, a substantially vertically extending supply conduit, and a substantially vertically extending discharge conduit. The branch conduit may be fluidly coupled to the tray conduit, the supply conduit, and the discharge conduit. The supply conduit may be configured to supply fluid to the tray conduit via the branch conduit. The discharge conduit may be configured to discharge fluid from the tray conduit via the branch conduit. The branch conduit may extend laterally between the supply conduit and the discharge conduit. The branch conduit may extend substantially horizontally.

[0019] The exhaust conduit may be selectively closeable to prevent fluid from being exhausted from the exhaust conduit, which allows water to fill up in the irrigation system when the exhaust conduit is closed.

[0020] The irrigation system may further comprise a drain valve selectively movable between an open position to allow fluid communication and a closed position to block fluid communication. The drain valve may be disposed between the branch conduit and the drain conduit. By controlling the drain valve, drainage from the growing trays can be controlled. If multiple branch conduits are provided, a drain valve may be disposed between each branch conduit and the drain conduit. Each drain valve may be individually controllable. This allows growing trays served by the same branch conduit to be treated as a batch and growing trays served by different branch conduits to be treated as separate batches.

[0021] The irrigation system may further comprise a supply valve selectively movable between an open position to allow fluid communication and a closed position to block fluid communication. The supply valve may be disposed between the branch conduit and the supply conduit. By controlling the supply valve, the supply of water to the growing trays may be controlled. If multiple branch conduits are provided, a supply valve may be disposed between each branch conduit and the supply conduit. The supply valve may be located on the branch conduit, on the supply conduit, or at an intersection between the branch conduit and the supply conduit. Each supply valve may be individually controllable. This allows growing trays served by the same branch conduit to be treated as a batch and growing trays served by different branch conduits to be treated as separate batches.

[0022] The branch conduit may define a drain overflow level at or near the drain conduit. Above the drain overflow level, fluid may flow from the branch conduit to the drain conduit. Below the drain overflow level, fluid may not flow from the branch conduit to the drain conduit. The drain overflow level may be higher than the branch conduit and lower than the bottom of the growth tray when positioned in the tray receiving location to allow fluid to be retained in the branch conduit at the drain overflow level after being drained from the growth tray. In this way, the time from when water is supplied to the supply conduit until the water enters the growth tray can be reduced for continuous supply and drain operations.

[0023] The branch conduit may define a feed overflow level at or near the feed conduit. Above the feed overflow level, fluid may flow from the branch conduit to the feed conduit. Below the feed overflow level, fluid may not flow from the branch conduit to the feed conduit. The feed overflow level may be higher than the tray conduit. The feed overflow level may be higher than at least a portion of the growth tray when positioned in the tray receiving location. The feed overflow level may be higher than a predetermined level of the growth tray when positioned in the tray receiving location.

[0024] The supply conduit and the discharge conduit may share a common service conduit. The branch conduit may be fluidly coupled to the tray conduit and the service conduit.

[0025] The irrigation system may further comprise a changeover valve assembly coupled between the service conduit and the branch conduit. The changeover valve assembly may comprise a supply conduit fluidly coupled to the service conduit, a discharge conduit fluidly coupled to the service conduit, and a flow diversion conduit fluidly coupled between the supply conduit and the discharge conduit and further fluidly coupled to the branch conduit. The flow diversion conduit may comprise a changeover member movable within the flow diversion conduit between a supply position where fluid communication between the discharge conduit and the flow diversion conduit is blocked and fluid communication between the supply conduit and the flow diversion conduit is open to allow fluid to flow from the service conduit to the branch conduit via the supply conduit and the flow diversion conduit, and a discharge position where fluid communication between the supply conduit and the flow diversion conduit is blocked and fluid communication between the discharge conduit and the flow diversion conduit is open to allow fluid to flow from the branch conduit to the service conduit via the flow diversion conduit and the discharge conduit. In this manner, the irrigation system may be more compact with fewer components.

[0026] The switching member may be freely movable within the flow diverter channel such that the switching member can be biased to a supply position when fluid is entering the supply channel from a service conduit and the switching member can be biased to a discharge position when fluid is entering the flow diverter channel from a branch conduit This allows the supply of water to and the discharge of water from the grow tray to be passively, rather than actively, controlled.

[0027] The supply conduit may include a supply flow regulator configured to regulate flow through the supply conduit to a predetermined supply flow rate. The exhaust conduit may include a discharge flow regulator configured to regulate flow through the exhaust conduit to a predetermined discharge flow rate. The predetermined supply flow rate may be different from the predetermined discharge flow rate, e.g., the predetermined supply flow rate may be higher than the predetermined discharge flow rate or vice versa.

[0028] The discharge conduit may further comprise a check valve configured to allow fluid to flow in a direction towards the service conduit and to prevent fluid from flowing in the opposite direction.

[0029] The supply and discharge channels may be oriented substantially horizontally and vertically spaced from one another. The flow diversion channel may be oriented substantially vertically. The diversion member may be vertically movable between the supply and discharge positions.

[0030] The supply conduit may be located below the discharge conduit. The branch conduit may be fluidly coupled to the top of the flow diverter conduit. The supply position of the diverter member may be vertically above the discharge position.

[0031] The supply conduit may be located at or near a first end of the flow diversion conduit and the discharge conduit may be located at or near a second end of the flow diversion conduit. The discharge position of the switching member may be located at the first end of the flow diversion conduit and the supply position of the switching member may be located at the second end of the flow diversion conduit.

[0032] The tray conduit may include a ring protrusion or ring recess for mating with a complementary ring recess or ring protrusion, respectively, that surrounds the irrigation opening of the growth tray when positioned in the tray receiving location. The tray conduit's ring protrusion or ring recess may surround an opening at the end of the tray conduit. The tray conduit's ring protrusion or ring recess may include an elastomeric member (e.g., an O-ring). By providing a ring bonding interface, the growth tray and tray conduit may be mated without leakage even when the growth tray is slightly horizontally offset from the tray conduit or tilted relative to the horizontal and in any rotational orientation when positioned in the tray receiving location.

[0033] The tray receiving location may include a positioning protrusion or recess that cooperates with a complementary positioning recess or protrusion, respectively, on the growth tray when positioned in the tray receiving location to prevent the growth tray from moving horizontally relative to the support structure.

[0034] The tray receiving location may include a support surface for supporting a growth tray positioned in the tray receiving location and a sloped guide surface for guiding the growth tray toward the support surface and positioning the growth tray on the support surface. The support surface may be disposed at a bottom of the slope of the sloped guide surface. The support surface may be disposed at least partially around a periphery of the tray receiving location.

[0035] The agricultural system may further comprise a growing tray. The growing tray may comprise a base and irrigation openings extending through the base. A bottom of the base may be coupleable to a tray conduit to enable fluid communication between the tray conduit and the growing tray when the growing tray is positioned in the tray-receiving location.

[0036] The bottom of the growth tray may include an annular recess or annular protrusion surrounding the irrigation opening of the growth tray for mating with an annular protrusion or annular recess, respectively, on the tray conduit when the growth tray is positioned in the tray receiving location. The annular recess or annular protrusion of the growth tray may include an elastomeric member (e.g., an O-ring).

[0037] The growth tray may include a positioning recess or a positioning protrusion for cooperating with a positioning protrusion or a positioning recess, respectively, in the tray receiving location when the growth tray is positioned in the tray receiving location. The positioning recess or protrusion of the growth tray may be located, for example, on a bottom of the growth tray or on a peripheral wall of the growth tray.

[0038] The support structure may define a plurality of vertically spaced levels, each level including one or more tray receiving locations. The irrigation system may include a plurality of branch conduits, each branch conduit may be fluidly coupled to one or more of the tray conduits at a particular level of the support structure.

[0039] method A method of using the above-mentioned agricultural system is provided, wherein the agricultural system further comprises a growing tray positioned in the tray receiving location and coupled to the tray conduit. The method comprises: (i) supplying fluid to an irrigation system to fill a growing tray with the fluid via a tray conduit; (ii) stopping the supply of fluid when the fluid reaches a predetermined fluid level in the growth tray; (iii) allowing fluid to exit the growth tray through the tray conduit; Equipped with.

[0040] This process allows for more precise control over the amount of fluid the growth tray receives and the period of time the growth tray is filled with fluid.

[0041] The fluid in the growth tray can be held at a predetermined fluid level for a predetermined period of time before allowing the fluid to drain from the growth tray.

[0042] Drain from the irrigation system may be shut off while fluid is being supplied to the irrigation system and enabled to allow fluid to drain from the growing trays. If the irrigation system is equipped with a drain valve, drain from the irrigation system may be shut off and enabled by closing and opening the drain valve, respectively.

[0043] Where the agricultural system comprises supply and drain valves, step (i) of the method may further comprise closing the supply and drain valves, supplying fluid to the supply conduit, and then opening the supply valve to fill the growing tray with fluid via the tray conduit. Step (ii) may further comprise closing the supply valve and stopping the supply of fluid to the supply conduit. Step (iii) may further comprise opening the drain valve to allow fluid to drain from the growing tray via the tray conduit.

[0044] Where the support structure defines multiple vertically spaced levels and the irrigation system comprises multiple branch conduits, the method may comprise supplying fluid to only a subset of the branch conduits (e.g., by opening a subset of the supply valves) such that only the growth trays on the levels corresponding to the subset of the branch conduits are filled with fluid. The method may comprise draining fluid from only a subset of the multiple branch conduits (e.g., by opening a subset of the drain valves) such that only the growth trays on the levels corresponding to the subset of the branch conduits are drained with fluid. In this manner, growth trays on different levels of the support structure may be treated as separate batches.

[0045] Switching valve assembly A diverter valve is provided that includes a supply conduit, a discharge conduit, and a flow diverter conduit fluidly coupled between the supply conduit and the discharge conduit.

[0046] The supply conduit may be fluidly connectable to the service conduit, the discharge conduit may be fluidly connectable to the service conduit, and the flow diversion conduit may be fluidly connectable to the branch conduit.

[0047] The flow diversion conduit may include a switching member movable within the flow diversion conduit between a supply position in which fluid communication between the discharge conduit and the flow diversion conduit is blocked and fluid communication between the supply conduit and the flow diversion conduit is opened, and a discharge position in which fluid communication between the supply conduit and the flow diversion conduit is blocked and fluid communication between the discharge conduit and the flow diversion conduit is opened.

[0048] The flow diversion conduit may be biased to a supply position when fluid is flowing from the supply conduit to the flow diversion conduit. The flow diversion conduit may be biased to a discharge position when fluid is flowing from the flow diversion conduit to the discharge conduit.

[0049] The supply conduit may include a supply flow regulator configured to regulate flow through the supply conduit to a predetermined supply flow rate. The exhaust conduit may include a discharge flow regulator configured to regulate flow through the exhaust conduit to a predetermined discharge flow rate. The predetermined supply flow rate may be different from the predetermined discharge flow rate, e.g., the predetermined supply flow rate may be higher than the predetermined discharge flow rate or vice versa.

[0050] The outlet conduit may further comprise a check valve configured to allow fluid to flow in a direction away from the flow diversion conduit and to prevent fluid from flowing in the opposite direction.

[0051] The supply and discharge channels may be oriented substantially parallel to one another. The flow diversion channel may be oriented substantially perpendicular to the supply and discharge channels.

[0052] The supply conduit may be located at or near a first end of the flow diversion conduit and the discharge conduit may be located at or near a second end of the flow diversion conduit. The discharge position of the switching member may be located at the first end of the flow diversion conduit and the supply position of the switching member may be located at the second end of the flow diversion conduit.

[0053] Growth tray A growing tray is provided. The growing tray may be for use in the agricultural system described above. The growing tray comprises a perimeter wall and a base with irrigation openings extending through the base for allowing fluid to enter and exit the growing tray. The base may be connectable to a conduit to allow fluid communication between the conduit and the base via the irrigation openings.

[0054] The irrigation opening may be disposed centrally in the base.

[0055] The base is may further comprise one or more primary channels extending between the irrigation openings and the perimeter wall, the one or more primary channels may divide the base into a plurality of adjacent sections; Each section includes a plurality of secondary conduits, each secondary conduit connected to at least one of the one or more primary conduits to enable fluid communication between the irrigation openings and the plurality of secondary conduits via the one or more primary conduits.

[0056] The base may include a plurality of primary channels extending radially from the irrigation openings toward the perimeter wall. A plurality of secondary channels may extend circumferentially around the irrigation openings between adjacent primary channels.

[0057] The multiple secondary channels may be configured to form multiple concentric rings about the irrigation opening.

[0058] The base may further comprise a plurality of tertiary channels extending radially between adjacent secondary channels to enable fluid communication between the adjacent secondary channels via the plurality of tertiary channels.

[0059] The base may include an inner portion including primary and secondary (and tertiary) channels. The base may further include a perimeter portion surrounding the inner portion. The perimeter portion may include a plurality of secondary perimeter channels extending perpendicularly from the perimeter wall to the inner portion for enabling fluid communication between the inner portion and the perimeter wall.

[0060] The primary and secondary channels may have different depths. The primary channel may be deeper than the secondary channel. The primary channel may be about twice as deep as the secondary channel.

[0061] The primary and secondary (and tertiary) channels may be defined by grooves in the base.

[0062] The base may include a substantially horizontal top surface for supporting a sheet of growing substrate in a substantially horizontal orientation.

[0063] The base may further include a plurality of radially extending fins positioned in the irrigation opening that partially define a substantially horizontal top surface.

[0064] The base may further include one or more main water channels extending between the irrigation openings and the perimeter wall, the one or more main water channels dividing the base into a plurality of adjacent sections. Each section may include a plurality of branch water channels, each branch water channel connected to one of the one or more main water channels to enable fluid communication between the irrigation openings and the plurality of branch water channels via the one or more main water channels. This configuration allows for an even distribution of water throughout the base and helps to avoid dead zones where water is difficult to reach or drain.

[0065] Each branch conduit may extend to the perimeter wall, or alternatively, each branch conduit may terminate short of the perimeter wall to form a perimeter conduit adjacent the perimeter wall.

[0066] Each branch channel within each section may extend in substantially the same direction.

[0067] Each branch channel may have substantially the same width as each other.

[0068] Each section may be sloped downwardly toward the irrigation opening to facilitate drainage. The branch channels in each section may extend in substantially the same direction as the slope of the section.

[0069] The one or more main channels and / or branch channels may extend substantially linearly.

[0070] The sections may have substantially the same area as one another. The sections may be symmetrically disposed about the irrigation opening. The sections may be substantially triangular. The number of sections formed by the main channels may be one more than the number of main channels.

[0071] The base may be substantially flat (i.e., all of the sections may be in the same plane). Alternatively, each section may slope downwardly toward the irrigation opening. The slope of each section may be about 1:50 or less. The slope of each section may be at least about 1:100. The slope of each section may be about 1:100 to 1:50. The slope of each section may be about 1:100, 1:90, 1:80, 1:70, 1:60, or 1:50.

[0072] The base may further include a plurality of upstanding ribs, and each branch channel may be defined between two adjacent ribs.

[0073] Each rib may have a wave-like shape (e.g., a sinusoidal shape), which provides strength to the rib and reduces the risk of the rib breaking off from its base, and as a result the rib may be thinner.

[0074] The tops of the plurality of ribs may provide a substantially horizontal surface for supporting a sheet of growing substrate in a substantially horizontal orientation, allowing the growing substrate to be lifted away from the base, which may facilitate drainage, and allowing the roots of the crop to be suspended in the air, which may be beneficial for crop growth.

[0075] Alternatively, the one or more main and branch channels may be defined by grooves in the base.

[0076] The bottom of the base may include a ring protrusion or ring recess surrounding the irrigation opening for cooperating with a complementary ring recess or ring protrusion, respectively, on the conduit to be bonded to the bottom of the base. By providing a ring bonding interface, the growth tray and conduit may bond without leakage even when the growth tray is slightly horizontally offset from the conduit or tilted relative to the horizontal, and in any rotational orientation.

[0077] The bottom of the base may further comprise a groove surrounding the annulus protrusion or annulus recess for receiving the end of the conduit, which may help to stabilize the connection between the growth tray and the conduit.

[0078] The base may further comprise a first pair of parallel perimeter edges. The growing tray may further comprise a first pair of diametrically opposed positioning features extending parallel to the first pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on the support structure. A midpoint of a positioning feature of the first pair of diametrically opposed positioning features may be aligned along a first axis running through a center of the irrigation opening and perpendicularly through the first pair of parallel perimeter edges.

[0079] This configuration may be advantageous if the growing tray shrinks during or after manufacturing (e.g., if the growing tray is formed using a plastic molding process). By aligning the positioning features and irrigation holes as described above, the relative positions of the midpoints of the positioning features and the centers of the irrigation holes may remain the same regardless of the amount of shrinkage. Thus, the growing tray is more likely to be aligned with the tray conduits in the agricultural system described above when positioned in a tray receiving location having a corresponding positioning feature.

[0080] The base may further include a second pair of parallel perimeter edges. The growing tray may further include a second pair of positioning features extending parallel to the second pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on the support structure. A midpoint of a positioning feature of the second pair of positioning features may be aligned along a second axis running through a center of the irrigation opening and perpendicularly through the second pair of parallel perimeter edges.

[0081] The positioning feature may be located on a bottom of the base, for example at or near the outer perimeter edge of the base. The positioning feature may be located on a perimeter wall.

[0082] The first and / or second pair of positioning features may be protrusions or recesses. The protrusions or recesses may have sloping sides, for example, they may be trapezoidal in shape, which allows the growing tray to self-position on the support structure.

[0083] The growth trays are one or more stacking projections disposed on one of: (i) a bottom side of the base; and (ii) a top of the perimeter wall; one or more complementary stacking recesses disposed on the other of (i) the bottom side of the base and (ii) the top of the perimeter wall; The device may further include:

[0084] The maximum height of one or more stacking protrusions may be greater than the maximum height of one or more stacking recesses to form vertical gaps between adjacent growth trays when stacked vertically. In this manner, air may flow between the growth trays in the stack, which may be beneficial for seed germination before the growth trays are moved onto the support structure.

[0085] The protrusions and recesses may have sloping sides, for example, they may have a trapezoidal shape, which allows the growing trays to self-position on top of each other when stacked.

[0086] The base can be rectangular (including square).

[0087] Hence, there is provided an agricultural system and method, and a tray for improving indoor agricultural systems.

[0088] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which like reference numerals are used to refer to like features, and in which: [Brief description of the drawings]

[0089] [Figure 1] FIG. 1 is a perspective view of an agricultural system showing a support structure, an irrigation system, and a growing tray. [Diagram 2] FIG. 2 is a front view of the agricultural system of FIG. 1. [Diagram 3] FIG. 2 is a perspective view of the agricultural system of FIG. 1 with the growing tray removed. [Figure 4] FIG. 1 is a schematic diagram of a variation of the irrigation system. [Diagram 5] FIG. 1 is a perspective view of an alternative agricultural system showing a support structure, an irrigation system, and growing trays. [Figure 6] FIG. 6 is a front view of the agricultural system of FIG. [Figure 7] FIG. 6 is a perspective view of a selector valve assembly used in the agricultural system of FIG. [Figure 8] 8 is a schematic cross-sectional view of the selector valve assembly shown in FIG. 7. [Figure 9] FIG. 2 is a perspective view of a first growing tray. [Figure 10] FIG. 10 is a partial perspective view of the bottom of the first growing tray of FIG. [Figure 11] FIG. 10 is a top view of the first growth tray of FIG. [Figure 12] FIG. 10 is a partial side view of the first growing tray of FIG. [Figure 13] FIG. 2 is a perspective view of a second growing tray. [Figure 14] FIG. 2 is a top view of a second growing tray. [Figure 15] FIG. 13 is a close-up view of the irrigation openings of the second growing tray. [Figure 16]FIG. 2 is a perspective view of the underside of a second growing tray. [Figure 17] FIG. 1 is a perspective view of a tray conduit for connecting to a first or second growth tray. [Figure 18] FIG. 13 is a perspective view of a second growing tray on a support structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0090] The present invention relates to an agricultural system, such as a hydroponic agricultural system, that includes, in combination or alone, a growing tray for containing growing crops, a support structure for supporting the growing tray, and an irrigation system for supplying and draining fluids to the growing tray on the support structure, each of these aspects being described in more detail in the following sections.

[0091] The fluids used in agricultural systems may be liquids or liquid solutions, for example water with dissolved nutrients or other substances for crop growth. Hereinafter, the term "water" includes water with dissolved nutrients or other substances. support structure

[0092] For convenience, a set of axes labeled X, Y, and Z is illustrated in Figure 1. In the following description, the term "vertical" refers to a direction parallel to the Z axis, and the term "horizontal" refers to a direction parallel to the XY plane.

[0093] 1 illustrates an agricultural system including a support structure 100 for receiving and supporting growing trays 300 in vertically spaced levels 101 defined by the support structure 100. Each level 101 includes at least one tray receiving location 102. Each tray receiving location 102 is configured to receive one growing tray 300. The support structure 100 of FIG. 1 has five levels 101, with each level 101 including four tray receiving locations 102. However, the support structure 100 may include more or fewer levels 101 (i.e., one or more levels), and each level 101 may include more or fewer tray receiving locations 102 (i.e., one or more tray receiving locations), depending on the crop yield required and the space available for the support structure 100.

[0094] The growing trays 300 are individually coupled to the irrigation system 200 and therefore each tray receiving location includes features that aid in properly positioning the growing trays 300 relative to the irrigation system 200 .

[0095] 2 shows a front view of the support structure 100. Each tray receiving location 102 includes a support surface 106 that supports a bottom of a growth tray 300 when placed in the tray receiving location 102. Each tray receiving location 102 further includes an inclined guide surface 105 for guiding the growth tray 300 toward the support surface 106 and positioning the growth tray 300 on the support surface 106. In particular, the support surface 106 is located at the bottom of the inclination of the guide surface 105, so that if the growth tray 300 is offset from the support surface 106 when placed in the tray receiving location 102, the growth tray 300 can engage and slide down the inclined guide surface 105, moving the growth tray 300 toward the support surface 106. The guide surface 105 thus serves to guide and position the growth tray 300 at a specific location on the support structure 100 such that the growth tray 300 can be coupled to the irrigation system 200.

[0096] The tray receiving locations 102 are defined, at least in part, by horizontal members 104 that include support surfaces 106 and guide surfaces 105. The horizontal members 104 are supported by vertical members 103. The support structure 100 is modular in the sense that it can be expanded to provide more tray receiving locations 102 by increasing the number of vertical members 103 and horizontal members 104.

[0097] The support structure 100 further comprises an artificial light source 107 mounted above each tray-receiving location 102 to provide light from above to each growing tray 300. The light source 107 may be a strip light (e.g., an LED strip light).

[0098] The support structure 100 may include additional positioning features that further aid in properly positioning the growth tray 300 relative to the irrigation system 200 and / or preventing horizontal movement of the growth tray 300 after it is placed in the tray receiving locations 102. For example, each tray receiving location 102 may include positioning features (not shown) that cooperate with complementary positioning features on the growth tray 300. These positioning features may take the form of, for example, protrusions on the support structure 100 that are received into recesses in the bottom of the growth tray 300, or vice versa.

[0099] Each tray receiving location 102 may be associated with a unique identifier, such as a bar code or RFID tag, attached to or adjacent each tray receiving location 102 that may be used to uniquely identify each tray receiving location 102 on the support structure 100. These unique identifiers, in combination with the unique identifier for each growth tray 300, may be used to record and track the location of each growth tray 300 on the support structure 100.

[0100] Irrigation Systems Figures 1-3 show an irrigation system 200 of an agricultural system. Figure 3 shows the system of Figure 1 with the growing tray 300 and artificial light source 107 removed so that the irrigation system 200 can be seen in more detail.

[0101] Irrigation system 200 is configured to supply fluid to and remove fluid from growing trays 300 positioned in tray-receiving locations 102 of support structure 100. The fluid will typically be a liquid or liquid solution, such as water having dissolved nutrients or other substances for crop growth.

[0102] Each growth tray 300 includes irrigation openings 303 extending through the base 301 of the growth tray 300 through which fluid from the irrigation system 200 may enter and exit the growth tray 300 .

[0103] The irrigation system 200 includes a tray conduit 204 for coupling to a growth tray 300. For each tray receiving location 102, the irrigation system 200 includes a tray conduit 204 coupleable to a bottom of the growth tray 300 when positioned in the tray receiving location 102 to enable fluid communication between the tray conduit 204 and the growth tray 300 via irrigation openings 303. In particular, the tray conduit 204 includes an opening disposed vertically below the growth tray 300 that aligns with the growth tray irrigation openings 303 when the tray conduit 204 is coupled to the growth tray 300.

[0104] Irrigation system 200 is configured to supply fluid to and drain fluid from growing trays 300 via tray conduits 204. In other words, irrigation system 200 does not require separate conduits to handle fluid supply and drainage for each growing tray 300.

[0105] The irrigation system 200 further comprises a number of branch conduits 203 , a supply conduit 201 and a discharge conduit 202 .

[0106] Each branch conduit 203 is fluidly coupled to one or more tray conduits 204 at a particular level 101 of the support structure 100. Each branch conduit 203 is further fluidly coupled between a supply conduit 201 and a discharge conduit 202. The supply conduits 201 and the discharge conduits 202 extend substantially vertically between the levels 101 of the support structure 100, and each branch conduit 203 extends laterally between the supply conduit 201 and the discharge conduit 202. Thus, the irrigation system 200 comprises vertically spaced branch conduits 203 corresponding to the vertically spaced levels 101 of the support structure 100. In use, fluid is directed from the supply conduits 201 through the branch conduits 203 to the tray conduits 204, and fluid is discharged from the tray conduits 204 through the branch conduits 203 to the discharge conduits 202.

[0107] Irrigation system 200 is configured to receive a supply of fluid into the top of supply conduit 201. The fluid may be pumped directly from a water supply or from an intermediate tank that allows the fluid to be treated before being pumped into supply conduit 201. For example, the fluid may be sterilized, nutrients may be dosed, and / or the pH may be modified.

[0108] The drain conduit 202 is configured to receive fluid drained under gravity from the growing trays 300. The drained fluid may be recirculated into the irrigation system 200 or may be used elsewhere in the agricultural facility.

[0109] The supply conduit 201 and exhaust conduit 202 may be attached to the vertical members 103 of the support structure 100 for support, or may be supported independently of the support structure 100 .

[0110] The irrigation system 200 further comprises a plurality of exhaust valves 207. Each exhaust valve 207 is coupled between the exhaust conduit 202 and the branch conduit 203 and is selectively movable between an open position to allow fluid communication between the exhaust conduit 202 and the branch conduit 203 and a closed position to block fluid communication between the exhaust conduit 202 and the branch conduit 203. Thus, when the exhaust valve 207 is closed, fluid entering the irrigation system 200 from the supply conduit 201 may exit the irrigation system 200 via the tray conduit 204.

[0111] The discharge valves 207 may be electrically controlled valves, such as solenoid valves. The discharge valves 207 may be individually controllable. In this way, fluid from each branch conduit 203 can be discharged individually, so that the growth trays 300 on different levels 101 can be considered as separate batches. If individual control of each branch conduit 203 is not required, the discharge valves 207 may be controlled as a group, or the discharge valves 207 may instead be provided at the bottom of the discharge conduits 202 (below the bottom-most level 101 of the support structure 100).

[0112] Generally, the exhaust conduit 202 is selectively closeable such that when the exhaust conduit 202 is closed, fluid is prevented from being exhausted therethrough.

[0113] The irrigation system 200 further comprises a plurality of supply valves 206. Each supply valve 206 is coupled between the supply conduit 201 and the branch conduit 203 and is selectively movable between an open position to allow fluid communication between the supply conduit 201 and the branch conduit 203 and a closed position to block fluid communication between the supply conduit 201 and the branch conduit 203.

[0114] Supply valves 206 may be located, for example, on each branch conduit 203 , on supply conduit 201 (eg, above or below the inlet to each branch conduit 203 ), or at the intersection between supply conduit 201 and branch conduit 203 .

[0115] The supply valves 206 may be electrically controlled valves, such as solenoid valves. The supply valves 206 may be individually controllable. In this manner, fluid to each branch conduit 203 may be supplied individually such that the growth trays 300 on different levels 101 may be considered separate batches. However, if the fluid supply to each branch conduit 203 does not need to be individually controlled, the supply valves 206 may be controlled as a group. Alternatively, the supply valves 206 may be removed entirely, and the control of the fluid into the supply conduit 201 serves as the control of the fluid into the branch conduit 203.

[0116] A method of using the irrigation system 200 to supply water to and remove water from the growing trays 300 positioned in the tray-receiving locations 102 of the support structure 100 will now be described.

[0117] Prior to the first use of the system, the supply conduit 201, the discharge conduit 202, the branch conduit 203 and the tray conduit 204 may be empty of water.

[0118] For example, growing trays 300 containing a sheet of growing medium and germinated seeds or growing crops are placed in tray receiving locations 102 on support structure 100. Each growing tray 300 includes irrigation openings 303 extending through a base 301 of the growing tray 300. When placed in tray receiving location 102, the bottom of base 301 of growing tray 300 couples to tray conduit 204 such that irrigation openings 303 of growing tray 300 are in fluid communication with tray conduit 204.

[0119] The supply valve 206 and the drain valve 207 are moved to a closed position and water is supplied into the supply conduit 201. Because the supply valve 206 is closed, the supply conduit 201 will begin to fill with water. Once the supply conduit 201 is full, the supply valve 206 is opened to allow water to flow from the supply conduit 201 into the branch conduit 203.

[0120] At this point, water is still being supplied into the supply conduit 201. Because the drain valve 207 is closed, water cannot enter the drain conduit 202, so the only route the water can take is out through the tray conduit 204 and into each growth tray 300 via the irrigation openings 303 in the base 301 of each growth tray 300. Each growth tray 300 therefore begins to fill with water from the bottom up.

[0121] Water is continuously supplied to the supply conduit 201 until the water in each growth tray 300 rises to a predetermined level (i.e., height) above the base 301 of the growth tray 300. Once the water reaches the predetermined level, the supply valve 206 is closed and the supply of water into the supply conduit 201 is stopped. The point at which the supply of water into the supply conduit 201 can be stopped (i.e., when the water in each growth tray 300 has reached the predetermined level) can be determined by knowing in advance the amount of water required to fill the irrigation system 200 and the growth trays 300 to the predetermined level. Once that amount of water has been supplied to the supply conduit 201 (e.g., by supplying water at a particular flow rate for a particular period of time), the supply of water to the supply conduit 201 can be stopped.

[0122] At this point, the water in the irrigation system 200 is stationary and the water in the growth tray 300 remains retained within the growth tray 300. The water is held in this state for a period of time (e.g., on the order of minutes or hours) to allow the roots of the crops in the growth tray 300 to absorb the water they need for optimal growth.

[0123] Drain valve 207 is then opened to drain the water from the growth trays 300, allowing the water in each growth tray 300 to drain under gravity through irrigation openings 303. The drain water is directed by branch conduit 203 into drain conduit 202, which may then direct the water to an area where it is retreated and reintroduced into irrigation system 200.

[0124] The steps described above may be repeated to perform subsequent water fill and drain operations.

[0125] When the crop is ready to be harvested, the growing trays 300 are removed from the support structure 100.

[0126] As discussed above, the water supply and drainage for each branch conduit 203 may be controlled independently relative to the other branch conduits 203. Thus, the growth trays 300 on different levels 101 of the support structure 100 may be treated as separate batches, and water may be supplied and drained at different times for each batch. For example, when the supply conduit 201 is filled with water, only a subset of the supply valves 206 may be opened to deliver water to the growth trays 300 on a particular level or levels 101 of the support structure 100. Similarly, only a subset of the drain valves 207 may be opened to drain water from the growth trays 300 on a particular level or levels 101 of the support structure 100.

[0127] Furthermore, if each supply valve 206 is constructed and arranged to selectively block fluid communication through the supply conduit 201 and selectively block fluid communication from the supply conduit 201 to the branch conduits (e.g., a three-way valve located at the intersection between the supply conduit 201 and the branch conduits 203), the supply conduit 201 need not be completely filled with water when only a subset of the branch conduits 203 are filled. For example, when only a particular branch conduit 203 is filled, that supply valve 206 can prevent water entering the top of the supply conduit 201 from flowing through that branch conduit 203, allowing the water to flow directly into the branch conduit 203 without having to first fill the supply conduit 201 from the bottom.

[0128] By providing each growing tray 300 with tray conduits 204 for both fluid supply and drainage, the amount of piping in the irrigation system 200 and the complexity of the irrigation system 200 can be reduced.

[0129] By supplying fluid directly into each growth tray from below, the amount of water supplied to each growth tray 300 can be more precisely controlled. As a result, the system can provide more optimal crop growth and more efficient water use. Additionally, the flow rate of fluid into and out of the growth trays 300 can be controlled such that the flow regime is laminar, which is less likely to disturb the seeds, crops, or growth media in the growth trays 300 compared to top-down watering systems, which may be more turbulent. For example, the flow rate of fluid into the supply conduit 201, the diameter of the tray conduits 204 and irrigation openings 303, etc., can be selected to provide laminar flow into and out of each growth tray 300.

[0130] Top-down watering systems also tend to rely on small drain holes in the base 301 of the growth tray 300 so that the water supply rate is higher than the drain rate to maintain a sufficient amount of water in the growth tray 300. However, small drain holes can easily be blocked by debris. In this system, the same tray opening is used for both fluid supply and fluid drainage, and both operations do not occur simultaneously. Thus, the opening in the tray can be relatively large, which reduces the risk of blockage, and even if the opening is blocked, the blockage will likely be cleared during the next fluid supply operation.

[0131] Although the irrigation system 200 shown in FIG. 3 has a single supply conduit 201 and a single exhaust conduit 202 positioned at either end of the support structure 100, the irrigation system 200 is not limited to this configuration and may instead include multiple supply conduits and / or multiple exhaust conduits, particularly if the support structure 100 defines multiple tray receiving locations 102 on each level.

[0132] For example, the support structure 100 and irrigation system 200 shown in Figure 3 may be considered a repeatable unit, i.e., the system may have multiple pairs of supply and exhaust conduits. Alternatively, multiple exhaust conduits may be coupled (via branching conduits) to a single supply conduit, or multiple supply conduits may be coupled (via branching conduits) to a single exhaust conduit.

[0133] Additionally, the growing trays 300 on a particular level of the support structure 100 may be served by multiple branch conduits rather than just one branch conduit.

[0134] Although the irrigation system 200 shown in Figure 3 has separate supply and drain conduits, it should be appreciated that a common service conduit can function as both a supply conduit and a drain conduit. In this case, a single set of valves can couple each branch conduit 203 to the service conduit, and the single set of valves would be opened and closed for both fluid supply and fluid drain operations. Valves can be provided at the bottom of the service conduits (below the bottom level 101 of the support structure 100) so that the service conduits can be selectively closed to prevent fluid from being drained from the service conduits during fluid supply operations.

[0135] Figure 4 is a schematic diagram of a variation of the irrigation system 200 of Figure 3 that allows some water to be retained in each branch conduit 203 after a drain operation. By retaining some water in the branch conduits 203 after a drain operation, the next supply operation is faster because the time required to fill the branch conduits 203 and tray conduits 204 with water before the growing trays 300 can begin to fill with water is reduced. This can be particularly advantageous when each level 101 of the support structure 100 contains many tray receiving locations 102 and each branch conduit 203 is relatively long.

[0136] The irrigation system in FIG. 3 and the irrigation system in FIG.

[0137] 4 illustrates a branch conduit 203 fluidly coupled to a plurality of tray conduits 204 that are fluidly coupled to a plurality of growing trays 300 positioned on the support structure 100 (not shown). The branch conduit 203 is further fluidly coupled between a supply conduit 201 and a discharge conduit 202. As previously described, a supply valve 206 is coupled between the supply conduit 201 and the branch conduit 203, and a discharge valve 207 is coupled between the discharge conduit 202 and the branch conduit 203. Although only one branch conduit 203 is shown in FIG. 4, an irrigation system may include a plurality of similar branch conduits 203 serving different levels 101 of the support structure 100.

[0138] The branch conduit 203 defines a discharge overflow level 211 at or near the discharge conduit 202. Above the discharge overflow level 211, water can flow from the branch conduit 203 into the discharge conduit 202 under gravity until it reaches the discharge overflow level 211. Conversely, below the discharge overflow level 211, water cannot flow from the branch conduit 203 into the discharge conduit 202.

[0139] The discharge overflow level 211 is higher than the branch conduit 203 and lower than the bottom of the growth tray 300 when positioned in the tray receiving location 102 (i.e., the discharge overflow level 211 is vertically positioned between the branch conduit 203 and the bottom of the growth tray 300). In this way, water can be completely drained from the growth tray 300 under gravity, but some water will remain in the branch conduit 203 and the tray conduit 204 at the discharge overflow level 211. Thus, during the next watering operation, the time lag between when the supply valve 206 opens and when the water fills the growth tray 300 can be reduced because less water is needed before the water starts to fill the growth tray 300. If the discharge overflow level 211 is just below the bottom of the growth tray 300, the time lag can be substantially negligible.

[0140] The discharge overflow level 211 may be defined by a first bend 210 of the branch conduit 203. For example, the discharge overflow level 211 may be defined by a U-bend or an S-bend, or a section inclined at any other angle, such as 45 degrees or greater than 0 degrees to 90 degrees, with respect to the horizontal.

[0141] The branch conduits 203 may also define a similar supply overflow level 209 at or near the supply conduit 201. The supply overflow level 209 may be higher than a predetermined level of the growth tray 300 coupled to the branch conduit 203. The supply overflow level 209 helps prevent water from draining from the branch conduits 203 into the supply conduit 201, thus allowing for an arrangement in which the supply valves 206 are located on the supply conduit 201 just below the inlet to each branch conduit 203, as shown in FIG. 4. This arrangement of the supply valves 206 allows each branch conduit 203 to be individually supplied with water by opening the supply valve 206 above the branch conduit 203 to be supplied and closing the supply valve 206 just below the branch conduit 203 to be supplied. This supply valve arrangement also allows a two-way valve (eg, a butterfly valve) to be used, which is less expensive compared to a three-way valve at the intersection between, for example, the branch conduit 203 and the supply conduit 201 .

[0142] The supply overflow level 209 may be defined by a second bend 212 of the branch conduit 203. The supply overflow level may be defined by a U-bend or an S-bend, or a section inclined at any other angle, for example, 45 degrees or greater than 0 degrees to 90 degrees, relative to the horizontal.

[0143] The provision of a supply overflow level 209 is independent of the exhaust overflow level 211. Each branch conduit 203 may have a exhaust overflow level 211 and / or a supply overflow level 209.

[0144] FIG. 5 shows an alternative agricultural system in which the fluid supply and discharge into each branch conduit 203 does not need to be actively controlled.

[0145] The support structure 100 shown in Figure 5 is the same as the support structure 100 shown in Figures 1 and 2 and therefore will not be described in further detail.

[0146] The irrigation system 250 includes a common service conduit 251 for supplying water to and draining water from the growing trays 300 (i.e., the service conduit 251 functions as both the supply conduit and the drain conduit 202 of the irrigation system 200 of FIG. 3).

[0147] The service conduit 251 extends substantially vertically between the levels 101 of the support structure 100 and may be attached to one of the vertical members 103 of the support structure 100 for support. At the bottom of the service conduit 251, below the bottom level of the support structure 100, a drain valve (not shown) is provided for selectively closing the service conduit 251 to prevent water from draining out of the service conduit 251.

[0148] Figure 6 is a front view of the system of Figure 5, showing each level 101 of the support structure 100 and the irrigation system 250 in more detail. The irrigation components for servicing the growing trays 300 on one level 101 of the support structure 100 are shown separately in Figure 7.

[0149] Similar to irrigation system 200 shown in Figure 3, irrigation system 250 includes a tray conduit 204 coupleable to the bottom of a growing tray 300, and a branch conduit 203 coupled between the tray conduit 204 and a service conduit 251. Although Figures 5-7 show one branch conduit 203 for each tray conduit 204, irrigation system 250 is not limited to this configuration and one branch conduit 203 may be coupled to one or more tray conduits 204.

[0150] Similar to the irrigation system shown in FIG. 4, the branch conduits 203 of the irrigation system 250 may define a discharge overflow level at or near the service conduit 251 for the purpose of retaining water in the branch conduit 203 after discharge.

[0151] Each branch conduit 203 is coupled to a service conduit 251 via a changeover valve assembly 260. At each level 101 of the support structure 100, the service conduit 251 is coupled to two changeover valve assemblies located on either side of the service conduit 251. The two changeover valve assemblies may be formed as a single unit, as shown in FIG. 7. However, the irrigation system 250 is not limited to this configuration. For example, at each level 101 of the support structure 100, the service conduit 251 may be coupled to only one changeover valve assembly 260 or to more than two changeover valve assemblies, depending on the number of branch conduits 203 coupled to the service conduit 251 at that level 101.

[0152] 8 is a schematic diagram of the selector valve assembly 260. The selector valve assembly 260 comprises three fluid conduits 261, 262, 263. The supply conduit 261 and the discharge conduit 262 are both coupled at one end to the service conduit 251. The supply conduit 261 and the discharge conduit 262 extend substantially parallel to each other and are spaced apart. The flow diversion conduit 263 extends substantially perpendicular to the supply conduit 261 and the discharge conduit 262 and is fluidly coupled therebetween. The flow diversion conduit 263 is further fluidly coupled to the branch conduit 203. In use, the supply conduit 261 and the discharge conduit 262 are oriented substantially horizontally, with the supply conduit 261 being disposed vertically below the discharge conduit 262. The flow diversion conduit 263 is oriented substantially vertically and is coupled to the branch conduit 203 at the top of the flow diversion conduit 263.

[0153] The supply water passage 261 includes a supply flow regulator 264 for adjusting the flow rate of the fluid flowing through the supply water passage 261 to a predetermined supply flow rate.

[0154] The discharge conduit 262 includes a discharge flow regulator 265 configured to regulate the flow of fluid through the discharge conduit 262 to a predetermined discharge flow rate.

[0155] The predetermined supply flow rate may be different from the predetermined exhaust flow rate. For example, the predetermined supply flow rate may be greater than or less than the predetermined exhaust flow rate.

[0156] The discharge conduit 262 further comprises a check valve 266 configured to allow water to flow through the discharge conduit 262 towards the service conduit 251 but prevent flow in the opposite direction.

[0157] The flow diversion channel 263 includes a diverter member 267 that is vertically movable within the slow diversion channel between a supply position 268 and a discharge position 269. The supply position 268 is at the top of the flow diversion channel 263 and the discharge position 269 is at the bottom of the flow diversion channel 263.

[0158] In the supply position 268, fluid communication is opened between the supply passage 261 and the flow diversion passage 263, and fluid communication is blocked between the discharge passage 262 and the flow diversion passage 263. In the discharge position 269, fluid communication is opened between the discharge passage 262 and the flow diversion passage 263, and fluid communication is blocked between the supply passage 261 and the flow diversion passage 263.

[0159] The switching member 267 is freely movable within the flow diversion channel 263 between the supply position 268 and the discharge position 269, such that the switching member 267 can be biased to one of the supply position 268 and the discharge position 269 depending on the direction of fluid flow through the flow diversion channel 263.

[0160] The switching member 267 and / or the conduits 261, 262, 263 may be shaped or comprise geometric features that contact or cooperate with one another when the switching member 267 is in the supply position 268 or the discharge position 269 to appropriately block fluid communication between the conduits. In the supply position 268, the switching member 267 may be biased against or cooperate with a supply seat to provide a seal between the flow diversion conduit 263 and the discharge conduit 262. Similarly, in the discharge position 269, the switching member 267 may be biased against or cooperate with a discharge seat to provide a seal between the flow diversion conduit 263 and the supply conduit 261. The supply seat and / or the discharge seat may comprise an elastomeric member, such as an O-ring.

[0161] When there is no water in the selector valve assembly 260, the selector member 267 may tend to rest in the drain position 269 due to gravity.

[0162] The switching member 267 may have a cylindrical shape with a diameter smaller than the diameter of the flow diversion passage 263 such that a circumferential gap exists between the switching member 267 and the wall of the switching valve assembly 260 that defines the flow diversion passage 263.

[0163] The selector valve assembly 260 is configured such that as water enters the supply passage 261 from the service conduit 251 and flows into the flow diverter passage 263, the force of the water on the switching member 267 can urge the switching member 267 upwardly towards the supply position 268. When the switching member 267 is in the supply position 268, the continued force of the water entering the supply passage 261 keeps the switching member 267 in the supply position 268 such that water cannot flow from the flow diverter passage 263 into the discharge passage 262. At the same time, water from the supply passage 261 can now flow through the flow diverter passage 263 (e.g., through the circumferential gap discussed above) into the branch conduit 203.

[0164] Conversely, when water enters the top of the flow diversion channel 263 from the branch conduit 203, the force of the water flowing against the top of the switching member 267 urges the switching member 267 to the discharge position 269 so that water can flow from the flow diversion channel 263 into the discharge channel 262 but cannot flow into the supply channel 261.

[0165] The switching member 267 may be denser than water so that the switching member 267 rests in the discharge position 269 when the water in the irrigation system 250 is stationary. However, the switching member 267 should be light enough so that it can be urged to the supply position 268 by the force of water entering the supply conduit 261 from the service conduit 251.

[0166] To facilitate the upward bias of the switching member 267 from the discharge position 269 to the supply position 268, the supply conduit 261 may be coupled to the flow diverter conduit 263 vertically below the flow diverter conduit 263 such that water may push against a bottom surface of the switching member 267 as it enters the supply conduit 261 from the service conduit 251. The bottom surface of the switching member 267 may be recessed to further facilitate the upward bias of the switching member 267 when water is pushing against the bottom surface of the switching member 267.

[0167] The flow diversion conduit 263 may include an annular drainage seat at the bottom of the flow diversion conduit 263 with an opening smaller than the diameter of the switching member 267. This allows a seal to be formed between the flow diversion conduit 263 and the supply conduit 261 when water enters the flow diversion conduit 263 from the branch conduit 203 and the switching member 267 is biased downward against the drainage seat. However, when water enters the supply conduit 261 from the service conduit 251, the water can still push against the bottom of the switching member 267 through the central opening in the annular drainage seat.

[0168] A method of using the irrigation system 250 to supply water to and remove water from the growing trays 300 positioned in the tray-receiving locations 102 of the support structure 100 will now be described.

[0169] Prior to initial use of the irrigation system 250, the service conduit 251, the selector valve assemblies 260, and the branch conduits 203 may be empty of water. The selector member 267 of each selector valve assembly 260 rests in the discharge position 269 due to gravity.

[0170] The drain valve at the bottom of the service conduit 251 is closed to prevent water from draining from the service conduit 251. Water is fed into the service conduit 251 from the top and the service conduit 251 fills with water.

[0171] When the water level in the service conduit 251 reaches above the selector valve assembly 260, the water in the service conduit 251 may enter the selector valve assembly 260. If a given supply flow rate is higher than a given discharge flow rate, water will tend to enter the selector valve assembly 260 through the supply conduit 261 instead of the discharge conduit 262 because the supply conduit 261 provides the path of least resistance. In either case, a check valve 266 in the discharge conduit 262 can prevent water from entering the selector valve assembly 260 through the discharge conduit 262.

[0172] The flow rate of water supplied into the service conduit 251 may be significantly greater than the predetermined supply flow rate of the selector valve assembly 260, so that the service conduit 251 will be completely filled with water before any significant amount of water begins to enter the valve assembly on the bottom level 101 of the support structure 100. Thus, water may enter the valve assemblies at each level 101 of the support structure 100 substantially simultaneously.

[0173] When water from the service conduit 251 enters the supply passage 261 of the diverter valve assembly 260, the flow of water from the supply passage 261 toward the flow diverter passage 263 urges the diverter member 267 upwardly to the supply position 268. This allows water to flow from the supply passage 261 into the flow diverter passage 263 where it can then flow to the growth tray 300 via the bifurcation and tray conduits 204 coupled to the flow diverter passage 263.

[0174] As water continues to be supplied to the service conduit 251, it continues to fill the growth tray 300 until it reaches a predetermined water level above the base 301 of the growth tray 300. Once the predetermined water level is reached, the water supply to the service conduit 251 is stopped.

[0175] At this point, the water in the irrigation system 250 is stationary and the water in the growth tray 300 remains retained in the growth tray 300. The water is held in this state for a predetermined amount of time (e.g., on the order of minutes or hours) to allow the roots of the crops in the growth tray 300 to absorb the water they need for optimal growth.

[0176] In this holding state, the switching member 267 is lowered to the discharge position 269. A check valve 266 in the discharge conduit 262 helps prevent water in the upper growth tray 300 from spilling out of the lower growth tray 300 via the discharge conduit 262.

[0177] The drain valve at the bottom of the service conduit 251 is then opened to drain the water from the growth trays 300. This allows the water in each growth tray 300 to drain under gravity through the tray conduit 204 and the branch conduit 203 into the flow diversion conduit 263 of the diverter valve assembly 260. The force of the water entering the top of the flow diversion conduit 263 from the branch conduit 203 urges the diverter member 267 downward to the discharge position 269 so that the water can flow from the flow diversion conduit 263 to the discharge conduit 262 and then into the service conduit 251 where it can be directed to an area to be retreated and reintroduced into the irrigation system 250.

[0178] Once the water has been drained from the growth trays 300, the drain valve may be closed and the cycle may be repeated again with the same batch of growth trays 300 or a new batch of growth trays 300.

[0179] Thus, irrigation system 250 may provide a more compact irrigation system with reduced components, and water flow into and out of each level of the storage structure may be passively controlled by a diverter valve assembly. Providing supply flow regulator 264 and drain flow regulator 265 allows desired water fill and drain rates, respectively, to be selected. For example, predetermined supply and drain flow rates may be selected such that the water flow into and out of growing tray 300 is laminar. Only the water supply into service conduit 251 and a single drain valve at the bottom of service conduit 251 may be actively controlled for water supply and drain.

[0180] Growth tray FIG. 9 shows a perspective view of a first illustrative growing tray 300 for use with the support structure 100 and irrigation system 200, 250 described above. The growing tray 300 can be made from plastic (e.g., a thermoplastic such as HDPE or nylon) and can be formed by known plastic molding processes, such as injection molding. In use, the growing tray 300 can contain a growing medium in which crops are grown from seeds. The growing tray 300 can be used for hydroponic crop growth. Typical growing media for hydroponic growth include mineral wool (e.g., ROCKWOOL®), perlite, vermiculite, coir, clay pellets, and the like. The growing tray 300 is particularly suited for use with growing media in the form of sheets, such as mineral wool sheets.

[0181] The growing tray 300 comprises a rectangular base 301 and a perimeter wall 302 that extends around the base 301 to form an open tray. The illustrated growing tray 300 has a square base (i.e., a regular rectangular base), however, the base 301 could also have an irregular rectangular shape, or another shape (e.g., or polygonal or circular).

[0182] The center of the base 301 includes an irrigation opening 303 extending through the base 301 that allows fluid from the irrigation system to enter and exit the growth tray 300. When the growth tray 300 is placed into the tray receiving location 102 on the support structure 100, the bottom of the base 301 couples to a tray conduit of the irrigation system such that the irrigation opening 303 and the tray conduit 204 are aligned to allow fluid communication between the growth tray 300 and the tray conduit 204 via the irrigation opening 303. The irrigation opening 303 may be the only opening in the growth tray 300 that is in fluid communication with the irrigation system when in use.

[0183] The irrigation opening 303 does not necessarily have to be in the center of the base 301. The irrigation opening 303 may instead be at an edge of the base 301, or at a corner of the base 301, or anywhere else on the base 301. However, a central irrigation opening 303 may advantageously provide more uniform filling and draining across the base 301. The irrigation opening 303 may be sized such that the flow of water into and out of the growing tray 300 is substantially laminar. The diameter of the irrigation opening 303 may be, for example, about 50 mm to 60 mm.

[0184] 10 is a bottom view of the growth tray 300 showing irrigation openings 303. The bottom side of the base 301 includes mating features surrounding the irrigation openings 303 for mating with corresponding mating features on the tray conduit 204. The mating features on the growth tray 300 include an annular body protrusion 304 that surrounds the irrigation openings 303 and may itself define an opening. The annular body protrusion 304 has a curved cross-section, e.g., a truncated circular cross-section, such that the protrusion 304 has an annular dome shape.

[0185] The corresponding mating feature on the tray conduit 204 (shown in FIG. 17) comprises a complementary annular body recess that surrounds an opening at the end of the tray conduit 204. The annular body recess may have a curved cross-section, for example a truncated circular cross-section, such that the recess has an annular cup shape.

[0186] The annular projection 304 of the growth tray 300 or the annular recess of the tray conduit 204 may further comprise an elastomeric member (eg, an O-ring) to provide a better seal between the tray conduit 204 and the growth tray 300 .

[0187] The annular connection between the growth tray 300 and the tray conduit 204 allows for good connection even if the growth tray 300 is slightly misaligned with the tray conduit 204 when the growth tray 300 is placed in the tray receiving location 102. For example, the annular projection 304 and the annular recess can still cooperate with each other even if the growth tray 300 and the tray conduit 204 are slightly misaligned horizontally, in any rotational orientation, or when the growth tray 300 is slightly tilted relative to the horizontal.

[0188] Instead of the ring-shaped protrusion 304 being provided on the growth tray 300 and the ring-shaped recess being provided on the tray conduit 204, the ring-shaped recess can instead be provided on the growth tray 300 and the ring-shaped protrusion 304 can be provided on the tray conduit 204.

[0189] The bottom side of the base 301 of the growth tray 300 may further comprise a wall 305 surrounding the annular body protrusion 304. The wall 305 is radially spaced from the annular body protrusion 304 to form a circumferential groove 306 that can receive the end of the tray conduit 204 when the tray conduit 204 is coupled to the growth tray 300. The groove 306, bounded radially inward by the annular body protrusion 304 and radially outward by the wall 305, may add stability to the coupling and help to prevent the tray conduit 204 from moving relative to the growth tray 300 when coupled together. Instead of providing the wall 305 to define the groove 306, the groove 306 may instead be defined as a recess in the bottom side of the base 301 itself.

[0190] Base 301 further comprises a plurality of ribs 313 upstanding from the top side of base 301. The tops of ribs 313 provide a substantially horizontal surface for supporting a sheet of growing medium in a substantially horizontal orientation. By supporting the growing medium on the tops of ribs 313, the growing medium is elevated off of base 301. This facilitates fluid transfer across base 301 and allows crop roots to be suspended, which may be beneficial for crop growth.

[0191] FIG. 11 is a top view of growth tray 300 showing the arrangement of ribs 313.

[0192] The base 301 includes four main channels 310, each extending radially outward from the irrigation openings 303 to a corner of the base 301. The four main channels 310 divide the base 301 into four adjacent triangular sections 311, each bounded by two main channels 310 and a portion of the perimeter wall 302.

[0193] Each section 311 includes a subset of ribs 313 from the plurality of ribs 313. The ribs 313 in each section 311 are spaced to define branch channels 312 between adjacent ribs 313. Each rib 313 in each section 311 extends between one of the main channels 310 that border the section 311 and a portion of the perimeter wall 302 that borders the section, such that each branch channel 312 is connected to one of the main channels 310 that border the section, and each main channel 310 is connected to multiple branch channels 312.

[0194] The main channel 310 and the branch channels 312 provide a fluid pathway across the base 301. In particular, as water enters the grow tray 300 through the irrigation openings 303, the water may flow through the main channel 310 into the branch channels 312. Conversely, as water exits the grow tray 300, the water may flow from each branch channel 312 through the main channel 310 to the irrigation openings 303.

[0195] The arrangement of the main channel 310 and branch channels 312 helps promote an even distribution of water across the base 301 and helps avoid dead zones. This arrangement also provides a relatively even distribution of space under the growing media, which helps avoid crop root lumping in certain areas of the growing tray 300.

[0196] The ribs 313 in each section 311 extend substantially parallel to one another such that the branching channels 312 in each section 311 extend substantially parallel to one another. The spacing between adjacent ribs 313 in each section 311 is substantially the same such that the branching channels 312 in each section 311 are substantially the same width as one another, which further promotes even distribution of water across the base 301 and helps promote even distribution of roots across the growing tray 300.

[0197] To facilitate greater and / or faster drainage of water into the irrigation openings 303, each section 311 may slope downwardly toward the irrigation openings 303. The ribs 313 in each section 311 may extend substantially parallel to the direction of slope of each section 311 so that water flowing through the branching channels can take the most direct path up and down the slope.

[0198] Each rib 313 has a wavy shape (e.g., a sinusoidal shape) when viewed from above. The wavy shape of the ribs 313 provides strength to the ribs 313 such that the ribs 313 are less likely to break laterally away from the base 301 compared to straight ribs.

[0199] The ribs 313 are not limited to the particular arrangement shown in Figure 11. The arrangement may vary depending on the shape of the base 301, the number and location of the main channels 310, the arrangement of the ribs 313 within each section, etc.

[0200] Generally, the base 301 includes one or more main conduits 310 extending between the irrigation openings 303 and the perimeter wall 302 (i.e., the one or more main conduits 310 are in direct fluid communication with the irrigation openings 303). The one or more main conduits 310 divide the base 301 into a number of adjacent sections 311. Each section 311 includes a number of branch conduits 312. Each branch conduit 312 is connected to one of the main conduits 310 to enable fluid communication between the irrigation openings 303 and the branch conduits 312 via the one or more main conduits 310.

[0201] Each section 311 is bounded by at least one main conduit 310 and a portion of the perimeter wall 302. Each branch conduit 312 may extend between one of the main conduits 310 and the perimeter wall 302. Each branch conduit 312 may extend to the perimeter wall 302, or each branch conduit 312 may terminate short of the perimeter wall 302 such that the perimeter conduit is formed adjacent the perimeter wall 302. The perimeter conduit may further help promote an even distribution of water across the base 301.

[0202] The branching channels 312 in each section 311 may extend substantially parallel to one another. The branching channels 312 may have substantially the same width as one another to further promote even distribution of water across the base 301 and promote even distribution of roots across the tray.

[0203] One or more of the main channels 310 and / or the branch channels 312 may extend substantially linearly despite the fact that the boundaries of the channels may not be linear (e.g., if undulating ribs 313 are used to define the channels). A channel may be considered to extend substantially linearly if a straight path can be drawn between both ends of the channel.

[0204] The sections 311 may have substantially the same area as one another. The sections 311 may be symmetrically disposed around the irrigation opening 303. The sections 311 may be substantially triangular. The number of sections 311 formed by the main channels 310 may be one more than the number of main channels 310.

[0205] The base 301 may be substantially flat (i.e., all sections 311 may be in the same plane). Alternatively, to promote more and / or faster drainage, each section 311 may slope downward toward the irrigation opening 303. The slope of each section 311 may be about 1:50 or less. The slope of each section 311 may be at least about 1:100. The slope of each section 311 may be about 1:100 to 1:50. The slope of each section 311 may be about 1:100, 1:90, 1:80, 1:70, 1:60, or 1:50. The branch channels 312 within each section 311 may extend substantially parallel to the direction of the slope of each section 311, so that water flowing through the branch channels 312 can take the most direct path up and down the slope.

[0206] The width of the main water channel 310 may be about 20 mm to 40 mm, for example 30 mm. The width of the branch water channel 312 may be about 40 mm to 60 mm, for example 50 mm.

[0207] As an example of an arrangement having one main water passage 310 , the irrigation opening 303 may be disposed in a corner of the base 301 and the main water passage 310 may extend from the irrigation opening 303 to an opposing corner of the base 301 .

[0208] If the base 301 includes multiple main water channels 310, each main water channel 310 may extend from the irrigation opening 303 to a respective corner of the base 301. Alternatively, each main water channel 310 may extend to a respective edge of the base 301.

[0209] The base 301 may include upstanding ribs 313 disposed in each section. The ribs 313 may be spaced such that each branch channel is defined between two adjacent ribs 313. The tops of the ribs 313 may provide a substantially horizontal surface for supporting a sheet of growing substrate in a substantially horizontal orientation. The height of the ribs 313 may be about 15 mm to 30 mm.

[0210] As each section 311 slopes towards the irrigation opening 303 , the height of the ribs 313 may increase towards the irrigation opening 303 in order to maintain a substantially horizontal surface provided by the tops of the ribs 313 .

[0211] Each rib 313 may have a wavy shape (e.g., a sinusoidal shape) when viewed from above. For wavy ribs 313, references in this description to the direction or orientation of the rib 313 refer to the direction or orientation of a neutral line that extends linearly between the peaks and valleys of the corrugation. The wavy shape of the ribs 313 provides strength to the ribs 313 such that the ribs 313 are less likely to break laterally away from the base 301 compared to straight ribs. However, the ribs 313 are not limited to being wavy and may be straight ribs 313 or some other shape, provided that they are spaced such that branch channels 312 are defined between adjacent ribs 313.

[0212] Instead of the branch channels 312 being defined by upstanding ribs 313, one or more of the main channels 310 and the branch channels 312 may be defined by grooves formed in the base 301. The top surface of the base 301 then provides a substantially horizontal surface for supporting a sheet of growing substrate in a substantially horizontal orientation.

[0213] The above-described arrangement of main channels 310 and branch channels 312 may be used in non-rectangular growth trays 300. For example, a base having an n-sided shape (where n is an integer greater than or equal to 3) may have n main channels 310, each extending to a respective corner or edge of the base 301. Alternatively, the tray may have a circular base 301, with one or more main channels 310 dividing the base 301 into multiple compartments.

[0214] As described above in connection with irrigation systems 200, 250, the growing tray 300 may be filled with water until the water in the growing tray 300 reaches a predetermined water level. This predetermined water level may be above the tops of the ribs 313 (or grooves) so that at least a portion of the growing medium is submerged underwater. For example, the predetermined water level may be about 1 mm to 5 mm above the tops of the ribs 313, more specifically about 2 mm to 5 mm above the tops of the ribs 313, or even more specifically about 3 mm to 4 mm above the tops of the ribs 313.

[0215] As described above in connection with the support structure 100, each tray receiving location 102 may include positioning features configured to cooperate with corresponding positioning features on the growth tray 300 to help position the growth tray 300 in the correct position relative to the tray conduits 204 of the irrigation system and to help prevent horizontal movement of the growth tray 300 once in the tray receiving location 102.

[0216] 9, a growth tray 300 includes four positioning recesses 314 disposed on the bottom of a base 301. Each positioning recess 314 is disposed at or near an edge of the base 301.

[0217] Each tray receiving location 102 may include a corresponding locating protrusion (not shown) that is received by a locating recess 314 on the bottom of the growth tray 300 when placed in the tray receiving location 102. The locating protrusion may be located on the horizontal member 104, for example.

[0218] 9 includes positioning recesses 314 on all four edges of the base 301, the tray receiving location 102 does not need to include a positioning protrusion for each positioning recess 314 of the growth tray 300. For example, it is sufficient to provide a pair of opposing positioning protrusions in each tray receiving location 102 to engage with a pair of opposing positioning recesses 314 of the growth tray 300. Even if the tray receiving location 102 only includes a pair of opposing positioning protrusions, the advantage of providing positioning recesses 314 on all four edges of the growth tray 300 is that due to the rotational symmetry of the growth tray 300, the growth tray 300 does not need to be rotated to a specific orientation before being placed in the tray receiving location 102.

[0219] The locating recess 314 and the locating protrusion may have sloped sides 316 (eg, may have a trapezoidal shape) so that the locating protrusion may self-locate in the locating recess 314 .

[0220] Instead of the growth tray 300 including the positioning recesses 314 and the tray receiving location 102 including the positioning protrusions, the growth tray 300 can include the positioning protrusions and the tray receiving location 102 can include complementary positioning recesses.

[0221] In each tray receiving location 102, the position of the positioning protrusion relative to the tray conduit 204 is the same as the position of the positioning recess 314 relative to the irrigation opening 303 of the growth tray 300, so that when the growth tray 300 is placed in the tray receiving location 102 and the positioning recess 314 and protrusions engage, the irrigation opening 303 and the tray conduit 204 should be aligned.

[0222] Each of the four locating recesses 314 extends parallel to a respective outer perimeter edge of the base 301. The four locating recesses 314 of the growing tray 300 are arranged in two diametrically opposed pairs. The midpoints of the first pair of locating recesses 314 are aligned along a first axis A that runs through the center of the irrigation opening 303 and perpendicularly through one of the pairs of opposed parallel edges of the base 301. The midpoints of the second pair of locating recesses 314 are aligned along a second axis B that runs through the center of the irrigation opening 303 and perpendicularly through the other pair of opposed parallel edges of the base 301.

[0223] In this manner, the midpoint of the locating recess 314 will be aligned with the center of the irrigation opening 303. Thus, as long as the locating recess 314 mates with the locating protrusion in the tray receiving location 102, the irrigation opening 303 will be aligned with the tray conduit 204.

[0224] It is known that in some plastic manufacturing techniques, e.g., injection molding, the plastic can shrink in size and cause distortion when cooled after being molded. This shrinkage effect can cause the positioning recesses 314 of the growth tray 300 to shift from their expected design position relative to the irrigation openings 303, which can lead to the irrigation openings 303 being misaligned with the tray conduits 204 when the growth tray 300 is positioned in the tray receiving location 102. The positioning recesses 314 of the growth tray 300 mitigate any manufacturing defects regardless of the amount of plastic shrinkage that occurs, even if the growth tray 300 shrinks in the X and / or Y directions.

[0225] For a rectangular base 301 having a central irrigation opening 303, each locating recess 314 is symmetrically positioned around the midpoint of a corresponding edge of the base 301. However, if the irrigation openings 303 are not positioned at the center of the base 301, the locating recesses 314 will be positioned elsewhere on the base 301 accordingly such that the midpoints of the locating recesses 314 and the centers of the irrigation openings 303 are aligned. The positions of the locating protrusions in the tray receiving location 102 relative to the tray conduit 204 will also change accordingly.

[0226] As mentioned above, the growing tray 300 is not limited to having two pairs of opposing positioning features 314. Only a pair of diametrically opposed positioning features 314 may be provided, with their midpoints aligned along an axis running through the center of the irrigation opening 303 and running perpendicularly through a pair of opposing parallel perimeter edges of the base 301. The positioning features also need not be located on the edges of the base 301, but instead may be located elsewhere on the base 301, or on the perimeter wall 302, for example.

[0227] The positioning recesses 314 on the bottom of the growing trays 300 may also function as stacking features that allow the growing trays 300 to be stacked vertically. Being able to stack the growing trays 300 vertically is useful when storing or transporting the growing trays 300. Additionally, ungerminated seeds may be sown in the growing trays 300, which are then stacked and placed in an optimal environment to allow the seeds to germinate before placing the trays on the support structure 100 of the system for the next stage of crop growth.

[0228] 9, the growth tray 300 further includes a plurality of stacking protrusions or castellations 315 upstanding from the top of the perimeter wall 302. For each positioning recess 314, a complementary stacking protrusion 315 is provided. When the growth trays 300 are stacked vertically, the stacking protrusions 315 of a particular growth tray 300 are received into the positioning recesses 314 of the growth tray 300 immediately above.

[0229] Like positioning recesses 314, each stacking protrusion 315 has sloping sides (e.g., a trapezoidal shape) that allow the growth trays 300 to self-position on top of one another when stacked.

[0230] 12 shows a partial side view of the growth tray 300. The maximum height 319 of the stacking protrusions 315 can be greater than the maximum height 318 of the positioning recesses 314 such that a vertical gap is formed between adjacent trays when the trays are stacked vertically. The vertical gap can be about 10 mm to 50 mm, or about 20 mm to 40 mm, or about 20 mm to 30 mm. The vertical gap can be about 10 mm, 20 mm, 30 mm, 40 mm, or 50 mm.

[0231] The vertical gap allows for air flow between stacked trays 300, which may be beneficial for seed germination. However, if a vertical gap between stacked trays is not required, the maximum height of the stacking protrusions 315 and positioning recesses 314 may be substantially the same. The stacking protrusions 315 and positioning recesses 314 also help prevent the growing trays 300 from moving horizontally relative to one another when stacked.

[0232] It should be appreciated that if the bottom of the tray 300 instead includes a locating protrusion, the top of the perimeter wall 302 would include a complementary stacking recess.

[0233] It will also be appreciated that for stacking purposes, the protrusions and recesses on the top and bottom of the growing trays 300 are not limited to the arrangement shown in Figure 9. For example, each edge of the growing trays 300 can be provided with more than one protrusion or recess, or the protrusions and recesses can be positioned at the corners.

[0234] It should be recognized that while the various aspects of the growth tray 300 described above (e.g., the coupling features for coupling to the tray conduit 204, the waterway arrangement, the positioning features for positioning the growth tray 300 on the support structure 100, and the stacking features) may function together to provide a growth tray 300 that is particularly suitable for use in the present agricultural system, each of the aspects may also exist independently of one another.

[0235] FIG. 13 shows a perspective view of a second illustrative growing tray 400 for use with the support structure 100 and irrigation system 200, 250 described above. Like the first growing tray 300, the second growing tray 400 can be made from plastic (e.g., a thermoplastic such as HDPE or nylon) and can be formed by known plastic molding processes, such as injection molding. In use, the growing tray 400 can contain a growing medium in which crops are grown from seeds. The growing tray 400 can be used for hydroponic crop growth. Typical growing media for hydroponic growth include mineral wool (e.g., ROCKWOOL®), perlite, vermiculite, coir, clay pellets, etc. The growing tray 400 is particularly suited for use with growing media in the form of sheets, such as mineral wool sheets.

[0236] Similar to the first grow tray 300, the second grow tray 400 includes a square base 401 and a perimeter wall 402 that extends around the base 401 to form an open tray. The center of the base 401 includes a circular irrigation opening 403 extending through the base 401 that allows fluid from an irrigation system to enter and exit the grow tray 400.

[0237] A top surface 420 of the base 401 provides a substantially horizontal surface for supporting a sheet of growing medium in a substantially horizontal orientation. The base 401 includes a plurality of grooves 421 in the top surface 420 that define a plurality of channels for retaining fluid and facilitating fluid transfer between the irrigation openings 403 and the remainder of the base 401.

[0238] 14 is a top view of the grow tray 400 showing the configuration of the water channels. The base 401 includes an inner portion 426 that includes a plurality of primary water channels 410 that extend radially outward from the irrigation openings 403 toward the perimeter wall 402. The primary water channels 410 are regularly spaced circumferentially. The base 401 further includes a plurality of circumferentially extending secondary water channels 412 that connect adjacent primary water channels 410. As with the first grow tray 300, the primary water channels 410 can be considered to divide the base into a plurality of adjacent sections, each section including a subset of the secondary water channels 412. The primary water channels 410 and secondary water channels 412 of the second grow tray 400 are synonymous with the main water channel 310 and branch water channel 312 of the first grow tray, respectively.

[0239] The secondary channels 412 are radially spaced and configured to form a plurality of concentric rings centered about the irrigation opening 403. The base 401 optionally further comprises a plurality of radially extending tertiary channels 425 extending between at least some of the concentric rings to connect radially adjacent secondary channels 412. The tertiary channels 425 are regularly spaced circumferentially and positioned between the primary channels 410. In this example, the tertiary channels 425 connect the secondary channels 412 in some of the outer concentric rings, but do not connect the secondary channels 412 in the inner concentric ring closest to the irrigation opening 403. This is because the secondary channels 412 in the outer concentric ring are longer than those in the inner concentric ring, and therefore the tertiary channels 425 serve to distribute fluid evenly between the longer secondary channels 412, which are not needed for the secondary channels 412 in the inner concentric ring due to their shorter length.

[0240] This configuration of primary channels 410, secondary channels 412, and tertiary channels 425 form a spider web-like pattern that facilitates even distribution of fluid across base 401. In particular, primary channels 410 distribute fluid to and from the irrigation openings, secondary channels 412 distribute fluid between primary channels 410, and tertiary channels 425 distribute fluid between secondary channels 412.

[0241] To further facilitate even distribution of fluid across the base 401, the primary channel 410, the secondary channel 412, and the tertiary channel 425 may have different depths from one another. In this example, the primary channel 410 is deeper than the secondary channel 412 and the tertiary channel 425, i.e., the grooves forming the primary channel 410 are deeper relative to the top surface 420 than the grooves forming the secondary channel 412 and the tertiary channel 425. The primary channel may be, for example, twice as deep as the secondary channel. The tertiary channel 425 may have the same depth as the secondary channel 412, or may be shallower or deeper than the secondary channel 412.

[0242] The base 401 further comprises a circumferential portion 427 defined between the inner portion 426 and the circumferential wall 402. The circumferential portion 427 has the shape of a square annulus surrounding the inner portion 426. The circumferential portion 427 comprises primary circumferential channels 428 at the interface between the circumferential portion 427 and the inner portion 426. The circumferential portion 427 further comprises regularly spaced secondary circumferential channels 429 extending perpendicularly between the primary circumferential channels 428 and the circumferential wall 402. This arrangement of the channels 428, 429 in the circumferential portion 427 facilitates uniform distribution of fluid up to the circumferential wall 402. However, the circumferential portion 427 is optional, and the web-like pattern of channels in the inner portion 426 can extend up to the circumferential wall 402. Like the channels in the inner portion 426, the primary perimeter channel 428 and the secondary perimeter channel 429 may have different depths to further facilitate uniform distribution of fluid. In this example, the primary perimeter channel 428 is deeper than the secondary perimeter channel 429. In particular, the primary perimeter channel 428 has the same depth as the primary channel 410 in the inner portion 426, and the secondary perimeter channel 429 has the same depth as the secondary channel 412 in the inner portion 426.

[0243] As with the first growing tray, the diameter of the irrigation openings 403 is sized such that the flow of water into and out of the growing tray 400 is substantially laminar. This may result in irrigation openings 403 having a relatively large diameter. To provide support to the sheet of growing medium in the region directly above the irrigation openings 403, the base 401 further comprises fins 430 extending radially into and around the irrigation openings 403, having a top surface approximately flush with the topmost surface 420 of the base 401. The fins 430 are shown in more detail in FIG.

[0244] 16 shows the underside of second growing tray 400. Similar to first growing tray 300, the bottom side of base 401 of second growing tray 400 includes a mating feature in the form of an annulus protrusion 404 that surrounds and defines irrigation openings 403.

[0245] 17 shows a complementary ring recess 205 surrounding an opening at the end of the tray conduit 204 for mating with the ring protrusion 404 of the growth tray 400 (or the ring protrusion 304 of the growth tray 300). When the tray conduit 204 and the growth tray 400 are mated together, the ring protrusion 404 of the growth tray 400 sits in the ring recess 205 of the tray conduit 204.

[0246] 16, similar to the first growth tray 300, the second growth tray 400 includes positioning features 414a, 414b that aid in positioning the growth tray 400 in the tray receiving location 102 in the correct position so that the growth tray 400 can be coupled to the tray conduit 204. In particular, the underside of the base 401 includes a first pair of positioning protrusions 414a that are diametrically opposed about the center of the irrigation opening 403 and a second pair of positioning protrusions 414b that are diametrically opposed about the center of the irrigation opening. Similar to the first growth tray 300, the midpoint of the first pair of positioning protrusions 414a and the center of the irrigation opening 403 are aligned along a first axis, and the midpoint of the second pair of positioning protrusions 414b and the center of the irrigation opening 403 are aligned along a second axis that is perpendicular to the first axis.

[0247] FIG. 18 shows a portion of the support structure 100 with an unoccupied tray receiving location 102 and an adjacent tray receiving location 102 occupied by a growth tray 400. Each tray receiving location 102 includes a pair of parallel bars 108 extending in the Y direction. The parallel bars 108 are spaced apart in the X direction (with the tray conduit 204 located therebetween) to define a positioning recess (gap) 109 between the parallel bars 108 for receiving the first pair of positioning protrusions 414a of the growth tray 400. The parallel bars 108 thus help to position the growth tray 400 in the correct position in the X direction. The first pair of positioning protrusions 414a of the growth tray 400 includes an inclined side 416 that can engage with the parallel bars 108 when the growth tray 400 is placed in the tray receiving location 102 to help position the first pair of positioning protrusions 414a in the positioning recess 109.

[0248] To aid in positioning the growth tray 400 in the correct position in the tray receiving location 102 in the Y direction, the tray receiving location 102 may further include a positioning recess (not shown) for receiving the second pair of positioning protrusions 414b. The positioning recess for receiving the second pair of positioning protrusions 414b may be formed on the pair of parallel bars 108. Alternatively, the second pair of positioning protrusions 414b may be omitted from the growth tray 400, and the tray receiving location 102 may include an end stop (not shown) that abuts against the rear side of the growth tray 400 when the growth tray 400 is pushed horizontally into the tray receiving location 102. The end stop may be positioned relative to the tray conduit 204 such that the irrigation openings 403 are aligned with the tray conduit 204 in the Y direction when the rear side of the growth tray 400 abuts against the end stop.

[0249] When used with irrigation system 200, 250, second growth tray 400 functions similarly to first growth tray 300. Fluid is delivered into growth tray 400 from below through irrigation openings 403. The fluid is then held in the growth tray for a predetermined period of time after which the fluid is allowed to drain out of irrigation openings 403.

[0250] The first and second growing trays 300, 400 can be placed into and removed from the tray receiving location 102 by a lifting vehicle. For example, an automated or manually controlled lifting vehicle can lift a growing tray 300, 400 from a stack, move it to a position next to the support structure 100, and place the tray in the desired tray receiving location 102. When a growing tray 300, 400 is ready to be removed from the support structure 100, the lifting vehicle can move to the tray receiving location 102, lift the tray from the tray receiving location 102, and transport it to another location, such as a harvesting station.

[0251] The first and second growing trays 300, 400 may include transfer mating features for cooperating with corresponding mating features on the lifting vehicle so that the growing trays 300, 400 do not slide relative to the lifting vehicle while being lifted. For example, the growing trays 300, 400 may include protrusions on the bottom of the bases 301, 401 that are received into recesses on components of the lifting vehicle (e.g., in a lifting arm or platform), or vice versa. As another example, the bottom of the tray bases 301, 401 may include one or more horizontally extending recesses or slots for receiving horizontally extending lifting arms of the lifting vehicle.

[0252] As discussed above in connection with support structure 100, each growing tray 300, 400 may also be provided with a unique identifier, such as an RFID tag, that uniquely identifies each growing tray 300, 400 so that its location within support structure 100 can be recorded and tracked. The unique identifier for each growing tray 300, 400 may also be linked to other variables, such as the type of crop being grown in the growing tray 300, 400 and the time spent at a particular tray receiving location 102.

[0253] The growing tray 300, 400 is intended to provide a single component for containing crops and coupling directly to an irrigation system such that the growing tray 300, 400 may be in direct fluid communication with the irrigation system. The present growing tray 300, 400 may be simpler to manufacture, easier to clean, and less handling is required to place the growing tray 300, 400 on the support structure 100. Additionally, the amount of water that enters the growing tray 300, 400 and is made available to the crops may be more precisely controlled.

[0254] Although some features of the growth trays of the present invention have been described in relation to the first growth tray 300 and other features have been described in relation to the second growth tray 400, one of ordinary skill in the art will recognize that any of the features of the first growth tray 300 can be used independently of the features of the second growth tray 400, and vice versa. For example, the waterway configuration of the first growth tray 300 can be used with the second growth tray 400, and vice versa, the stacking protrusions 315 and / or positioning recesses 314 of the first growth tray 300 can be used with the second growth tray 400, and vice versa, and so forth.

[0255] Detailed descriptions of features of the first growth tray 300 that are similar or equivalent to the second growth tray 400 (e.g., annular body coupling features, alignment between positioning protrusions and irrigation openings, feature shapes and dimensions, etc.) have not been repeated in full for brevity, but remain applicable to the second growth tray 400.

[0256] The systems and devices described above with reference to the drawings allow for the controlled provision of water to crops in a controlled indoor agricultural environment, therefore crop yield, quality and growth time may be improved and the shelf life of the product may be optimized.

[0257] It should be appreciated that agricultural systems, methods, and devices can be designed for specific applications using various combinations of the devices and configurations described above. It should be appreciated that all of the features described above can be used together in a single system. In other embodiments of the invention, some of the features may be omitted. The features may be used in any compatible configuration. Many variations and modifications not expressly described above are possible without departing from the scope of the invention as defined in the appended claims. The invention as originally claimed in the present application is set forth below. [1] A growth tray comprising: An outer wall; a base with irrigation openings extending through the base for allowing fluid to enter and exit the growing tray; wherein the base is coupleable to a conduit to allow fluid communication between the conduit and the base through the irrigation openings. [2] The growth tray of [1], wherein the irrigation opening is disposed at the center of the base. [3] The base portion comprises: one or more primary channels extending between the irrigation openings and the perimeter wall, the one or more primary channels dividing the base into a plurality of adjacent sections; A growth tray as described in [1] or [2], wherein each section comprises a plurality of secondary water channels, each secondary water channel being connected to at least one of the one or more primary water channels to enable fluid communication between the irrigation openings and the plurality of secondary water channels via the one or more primary water channels. [4] The growth tray of [3], wherein the base includes a plurality of primary channels extending radially from the irrigation opening toward the outer circumferential wall, and the plurality of secondary channels extending circumferentially around the irrigation opening between adjacent primary channels. [5] The growth tray of [4], wherein the secondary channels are configured to form a plurality of concentric rings centered on the irrigation opening. [6] The growth tray of [4] or [5], wherein the base further comprises a plurality of tertiary channels extending radially between adjacent secondary channels to enable fluid communication between the adjacent secondary channels via the plurality of tertiary channels. [7] A growth tray described in any one of [3] to [6], wherein the base comprises an inner portion having the primary and secondary water channels, and an outer peripheral portion surrounding the inner portion, the outer peripheral portion comprising a plurality of secondary outer peripheral water channels extending perpendicularly from the outer peripheral wall to the inner portion to enable fluid communication between the inner portion and the outer peripheral wall. [8] The growth tray described in any one of [3] to [7], wherein the one or more primary water channels are deeper than the multiple secondary water channels. [9] The growth tray described in any one of [3] to [8], wherein the primary and secondary water channels are defined by grooves in the base.

[10] The growth tray of any one of [3] to [9], wherein the base comprises a substantially horizontal top surface for supporting a sheet of growth substrate in a substantially horizontal orientation.

[11] The growth tray of

[10] , wherein the base further comprises a plurality of radially extending fins located at the irrigation openings that partially define the substantially horizontal top surface.

[12] A growth tray as described in any one of [1] to

[11] , wherein the bottom of the base includes an annular protrusion or annular recess surrounding the irrigation opening for cooperating with a complementary annular recess or annular protrusion, respectively, on a conduit to be coupled to the bottom of the base.

[13] The growth tray of

[12] , wherein the bottom of the base further comprises a groove surrounding the annular projection or annular recess for receiving an end of the conduit.

[14] The base further comprises a first pair of parallel peripheral edges; the growth tray further comprising a first pair of diametrically opposed positioning features extending parallel to the first pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on a support structure; a midpoint of a positioning feature of the first pair of diametrically opposed positioning features is aligned along a first axis running through a center of the irrigation opening and perpendicularly through the first pair of parallel perimeter edges. The growth tray according to any one of [1] to

[13] .

[15] The base further comprises a second pair of parallel peripheral edges; the growing tray further comprising a second pair of positioning features extending parallel to the second pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on a support structure; a midpoint of a positioning feature of the second pair of positioning features is aligned along a second axis running through a center of the irrigation opening and perpendicularly through the second pair of parallel perimeter edges.

[14] A growth tray as described in

[14] .

[16] The growth tray of

[14] or

[15] , wherein the first and / or second pair of positioning features are protrusions or recesses.

[17] one or more stacking projections disposed on one of (i) a bottom side of the base and (ii) a top side of the perimeter wall; one or more complementary stacking recesses disposed on the other of (i) a bottom side of the base and (ii) a top side of the perimeter wall; The growth tray of any one of [1] to

[16] further comprises a maximum height of the one or more stacking protrusions that is greater than a maximum height of the one or more stacking recesses so as to form a vertical gap between adjacent growth trays when stacked vertically.

[18] The growth tray of

[17] , wherein the protrusions and recesses have a trapezoidal shape.

Claims

1. 1. A growing tray comprising: An outer wall; a base with irrigation openings extending through the base for allowing fluid to enter and exit the growing tray; the base being coupleable to a conduit to allow fluid communication between the conduit and the base through the irrigation openings; the irrigation opening is disposed centrally in the base; The base portion is one or more primary channels extending between the irrigation openings and the perimeter wall, the one or more primary channels dividing the base into a plurality of adjacent sections; each section comprises a plurality of secondary channels, each secondary channel being connected to at least one of the one or more primary channels to enable fluid communication between the irrigation openings and the plurality of secondary channels via the one or more primary channels; the base includes a plurality of primary channels extending radially from the irrigation openings toward the outer perimeter wall, the plurality of secondary channels extending circumferentially around the irrigation openings between adjacent primary channels; The base further comprises a plurality of tertiary channels extending radially between adjacent secondary channels to allow fluid communication between the adjacent secondary channels via the plurality of tertiary channels.

2. The growing tray of claim 1 , wherein the plurality of secondary channels are configured to form a plurality of concentric rings about the irrigation opening.

3. 3. The growth tray of claim 1 or 2, wherein the base comprises an inner portion comprising the primary and secondary channels and a peripheral portion surrounding the inner portion, the peripheral portion comprising a plurality of secondary peripheral channels extending perpendicularly from the peripheral wall to the inner portion to enable fluid communication between the inner portion and the peripheral wall.

4. The growth tray of any one of claims 1 to 3, wherein the one or more primary channels are deeper than the plurality of secondary channels.

5. The growing tray of any one of claims 1 to 4, wherein the primary and secondary channels are defined by grooves in the base.

6. The growing tray of any one of claims 1 to 5, wherein the base comprises a substantially horizontal top surface for supporting a sheet of growing substrate in a substantially horizontal orientation.

7. 7. The growing tray of claim 6, wherein the base further comprises a plurality of radially extending fins located at the irrigation openings that partially define the substantially horizontal top surface.

8. 8. The growing tray of any one of claims 1 to 7, wherein the bottom of the base comprises an annular protrusion or annular recess surrounding the irrigation opening for cooperating with a complementary annular recess or annular protrusion, respectively, on a conduit to be coupled to the bottom of the base.

9. 9. The growth tray of claim 8, wherein the bottom of the base further comprises a groove surrounding the annulus protrusion or annulus recess for receiving an end of the conduit.

10. the base further comprises a first pair of parallel peripheral edges; the growing tray further comprising a first pair of diametrically opposed positioning features extending parallel to the first pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on a support structure; a midpoint of a positioning feature of the first pair of diametrically opposed positioning features is aligned along a first axis running through a center of the irrigation opening and perpendicularly through the first pair of parallel perimeter edges. The growth tray according to any one of claims 1 to 9.

11. the base further comprises a second pair of parallel peripheral edges; the growing tray further comprising a second pair of positioning features extending parallel to the second pair of parallel perimeter edges for cooperating with a complementary pair of positioning features on a support structure; a midpoint of a positioning feature of the second pair of positioning features is aligned along a second axis running through a center of the irrigation opening and perpendicularly through the second pair of parallel perimeter edges. The growth tray of claim 10.

12. The growing tray of claim 10 or 11, wherein the first and / or second pair of positioning features are protrusions or recesses.

13. (i) one or more stacking projections disposed on one of a bottom side of the base and (ii) a top side of the perimeter wall; one or more complementary stacking recesses disposed on the other of (i) a bottom side of the base and (ii) a top side of the perimeter wall; 13. The growth tray of claim 1, further comprising: a maximum height of the one or more stacking protrusions that is greater than a maximum height of the one or more stacking recesses to form a vertical gap between adjacent growth trays when stacked vertically.

14. The growing tray of claim 13 , wherein the protrusions and recesses have a trapezoidal shape.

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