VENTILATED AIR DUCTS

Abstract

An air duct system, such as for indoor farming, includes a ventilated air duct assembly coupled to a fan, typically via an air housing. The air duct assembly has a pair of duct sections with upper and lower panels and a pair of side panels. The panels are hinged together at respective edges to form a generally rectangular shape when expanded to a use configuration. The duct sections can be collapsed to a flat storage configuration in which the upper panel and one side panel lie atop the lower panel and the other side panel. A duct junction with rectangular cross section has opposite open ends that engage respective open ends of the duct sections to secure the duct sections in fluid communication with one another in an end-to-end arrangement. One or more of the duct section panels have air outlet openings formed in them.

Description

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. provisional application Ser. No. 63/602,195, filed Nov. 22, 2023, which is hereby incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present application relates to air ducts for ventilation systems and, in particular, to air ducts for use in warehouses, work spaces, indoor grow facilities, and the like.

BACKGROUND

Ventilation systems are commonly used in indoor farming applications, and are used to circulate treated or untreated air to plant growing areas. Ventilation may be provided by simple fans mounted or placed within an indoor farm facility, or by duct-based systems that utilize ducts for directing air into desired locations and in desired directions. Ventilation systems may be used to provide various functions in such facilities, such as regulating air temperature, providing controlled concentrations of carbon dioxide (CO₂) or other gases in the air mixture, adding or removing humidity in the air, reducing growth of mildew or undesirable bacteria, viruses, or microbes, filtering particulates from the air, etc. Duct-based ventilation systems for indoor farming include those disclosed in commonly-assigned U.S. Pat. Nos. 11,582,920; 11,641,810; and 11,632,915, for example.

SUMMARY

The present disclosure provides air ducts and associated duct-based ventilation systems that are relatively light-weight and low-cost, and that are easier to set up, move around a facility, and ship, compared to conventional air ducts and duct-based ventilation systems. The air ducts may be fabricated from corrugated plastic sheets having pre-formed corners such that the four sides of a rectangular-section duct may be laid flat as two layers, and then manipulated to separate the two layers into an upper panel, a lower panel, and two side panels that are all joined together to define a rectangular air passageway. Multiple duct sections formed this way may be joined together in end-to-end arrangement to achieve a desired overall length, using fasteners and/or junction pieces. Optionally, metal wire reinforcement may be used to improve the junction pieces' and/or duct sections' rigidity. A resulting duct system can be very light in weight, requiring relatively light-duty fasteners or mounts for securing to other structures such as tiers of vertical farming racks, easily set up with basic tools (or in some cases with no tools required), and easily transported and shipped in a collapsed configuration.

In one embodiment, a ventilated air duct assembly includes a pair of duct sections, each having an upper panel having opposite side edges, a lower panel having opposite side edges, a pair of opposite side panels having upper and lower edges, and a duct junction. The upper edges of the side panels are hingedly coupled to respective ones of the opposite side edges of the upper panel, and the lower edges of the side panels are hingedly coupled to respective ones of the opposite side edges of the lower panel. At least one of the panels defines a plurality of air outlet openings. The first and second duct sections are configurable between an expanded use configuration having a generally rectangular cross section and a generally flat storage configuration in which a first of the opposite side panels and a portion of the upper panel lie against the lower panel, and another portion of the upper panel lies against a second of the opposite side panels. The duct junction has a generally rectangular cross section corresponding to the generally rectangular cross sections of the first and second duct sections in the expanded use configuration. The duct junction has opposite open ends that are configured to engage respective open ends of the first and second duct sections in the expanded use configuration, to secure the first duct section to the second duct section in fluid communication with one another.

Optionally, the duct junction includes a diffuser plate disposed between the opposite open ends.

According to one aspect, an outer surface of the duct junction includes a ridge projecting outwardly therefrom, the ridge arranged between and generally parallel to the opposite open ends, wherein the opposite open ends of the duct junction are insertable into the open ends of the first and second duct sections so that the first and second duct sections each abut an opposite side of the ridge. Optionally, the ridge is a rectangular ridge projecting outwardly around the entire periphery of the duct junction. The duct junction may be made from a unitarily-formed injection-molded resinous plastic material, for example.

According to another aspect, the duct junction includes an upper panel having opposite side edges, a lower panel having opposite side edges, and a pair of opposite side panels having upper and lower edges. The upper edges of the duct junction side panels are hingedly coupled to respective ones of the duct junction opposite side edges of the duct junction upper panel, and the duct junction lower edges of the duct junction side panels are hingedly coupled to respective ones of the duct junction opposite side edges of the duct junction lower panel.

According to another aspect, the duct junction has interior dimensions corresponding to exterior dimensions of the first and second duct sections, and wherein the duct junction in the expanded use configuration is sized and shaped to sleeve over the respective open ends of the first and second duct sections in their expanded use configuration.

According to yet another aspect, the duct junction is configurable between an expanded use configuration having a generally rectangular cross section and a generally flat storage configuration in which a first of the opposite duct junction side panels and a portion of the duct junction upper panel lie against the duct junction lower panel, and another portion of the duct junction upper panel lies against a second of the opposite duct junction side panels.

Optionally, the duct junction is made from corrugated plastic sheet material.

According to a further aspect, the duct junction includes a metal reinforcement wire disposed inside of the corrugated plastic sheet material.

According to a further aspect, the duct junction is made from a single sheet of the corrugated plastic material having opposite edge regions secured together.

In still another aspect, the opposite edge regions are secured together with at least one chosen from push-fasteners, threaded fasteners, adhesive bonding, heat welding, ultrasonic welding, staples, rivets, and magnets. Optionally, the opposite side edge regions overlap with one another.

In a further aspect, the panels of the first and second duct sections are made from corrugated plastic sheet material, or from single-layer plastic sheet material.

In another aspect, the first and second duct sections are each made from a single sheet of the corrugated plastic material having opposite edge regions secured together. The opposite edge regions may overlap with one another, and may be secured together with at least one chosen from push-fasteners, threaded fasteners, adhesive bonding, heat welding, ultrasonic welding, staples, rivets, and magnets.

According to yet another aspect, the hinged couplings are living hinges of resinous plastic.

Optionally, the ventilated air duct assembly is part of a ventilated air duct system including an air housing having an inlet and an outlet, a fan fluidly coupled to the inlet, and an end cap coupled to an end of the second duct section opposite the duct junction, with the first duct section is fluidly coupled to the outlet of the air housing. Optionally, the air housing is made from resinous plastic sheet material or from molded resinous plastic.

Optionally, the ventilated air duct system is combined with a grow rack system having at least one shelf supported by a plurality of uprights, such as with the ventilated air duct assembly supported along the grow rack system and extends from one pair of the uprights to an opposite pair of the uprights. Optionally, the fan is mounted outside a volume defined by the plurality of uprights.

Therefore, the air ducts and associated duct-based ventilation system provides a relatively light-weight, compact, and low-cost way to distribute air or other gases within an environment, such as an indoor farming facility. By using common and inexpensive materials and minimal fasteners, with ducts that can be cut-to-length with a simple box cutter or similar hand tool, the system can be readily assembled, installed, removed, disassembled, cleaned, reinstalled, and moved as desired.

These and other objects, advantages, purposes and features of the present application will become apparent upon review of the following specification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a two-tier grow rack system fitted with a ventilated air duct system;

FIG. 2 is an enlarged view of the area designated “2” in FIG. 1;

FIG. 3 is an end elevation view of the grow rack system and ventilated air duct system of FIG. 1;

FIG. 4 is a perspective view of the air housing of the ventilated air duct system of FIG. 1. 1;

FIG. 5 is a perspective view of another air housing compatible for use with the ventilated air duct system of FIG. 1;

FIG. 6 is a perspective view of a fan, a duct, and an air housing of a ventilated air duct system similar to that of FIG. 1;

FIGS. 7 and 8 are perspective views of the air housing of FIG. 6;

FIG. 9 is a perspective view of two pair of ventilated air ducts compatible for use with ventilated air duct system of FIG. 1;

FIG. 10 is a perspective view of one of the ventilated air ducts of FIG. 9;

FIG. 10A is an enlarged view of the open end of the duct in the area designated “10A” in FIG. 10;

FIG. 11A is a perspective view of another air housing for use with the ventilated air duct system of FIG. 1;

FIG. 11B is another perspective view of the air housing of FIG. 11A, shown with diffusers separated from respective air outlets;

FIG. 12 is an exploded perspective view of a pair of ventilated duct sections and a junction piece compatible for use with ventilated air duct system of FIG. 1;

FIG. 13 is a sectional view of one of the ventilated duct sections of FIG. 12, taken along line 13-13 in FIG. 12;

FIGS. 14A-14D are a series of end elevation views of one of the ducts of FIG. 12, showing transition from an expanded use configuration to a collapsed configuration for storage or shipping;

FIG. 15 is a perspective view of a junction piece of FIG. 12;

FIG. 16 is a side sectional view of the junction piece taken along line 16-16 of FIG. 15, and showing an internal diffuser panel;

FIG. 17 is a top plan view of the junction piece of FIG. 15;

FIG. 18 is an end elevation view of the junction piece of FIG. 15, showing the internal diffuser panel;

FIG. 19 is an exploded perspective view of a pair of ventilated ducts configured for joining by a sleeve-type junction piece, and with an end cap;

FIG. 19A is an enlarged view of the area designated “19A” in FIG. 19;

FIG. 20 is a perspective view of the ventilated ducts and sleeve-type junction piece of FIG. 19 shown in an assembled configuration;

FIG. 20A is an enlarged view of the area designated “20A” in FIG. 20;

FIG. 21 is a perspective view of the sleeve-type junction piece of FIG. 19, with internal reinforcement structure shown in phantom lines;

FIG. 22 is an end elevation view of one of the ventilated ducts of FIG. 20, shown while internally pressurized with a flow of gas;

FIG. 23 is an end elevation view of the sleeve-type junction piece of FIG. 19 fitted to the internally pressurized ventilated duct of FIG. 22;

FIG. 24 is a perspective view of a flat-plan sheet material used for forming the end cap of FIG. 19;

FIG. 25 is a perspective view of the formed end cap of FIG. 19;

FIG. 26 is a perspective view of the end cap and corresponding end of one of the ventilated ducts of FIG. 19;

FIG. 27 is a perspective view of a hanger support for attaching the ventilated ducts to the rack system of FIG. 1; and

FIG. 28 is an end elevation view of the hanger support of FIG. 27.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings and the illustrative embodiments depicted therein, a storage or grow rack system 100 includes six uprights 102, side support beams 104, end support beams 106, and two tiers of shelves 108a, 108b supported by the uprights 102, such as shown in FIGS. 1-3. A ventilated air duct system 110 is provided for directing air at plants supported on the lower shelf 180a and/or the upper shelf 108b. Air duct system 110 includes a fan 112 coupled to an inlet 114a of an air housing 114, and an air duct assembly 116 coupled to an outlet 114b of the air housing 114 (FIGS. 2-4). Another air housing 314 (FIG. 5) is functionally similar to air housing 114, but is constructed of corrugated plastic sheet material that is cut, folded, and bonded to achieve a similar shape as air housing 114. Still another air housing 114′ (FIGS. 6-8 may be formed from molded resinous plastic and fitted with a fan 112′ coupled to an inlet 114a′ of the air housing 114′, which has an air outlet 114b′ for coupling to a duct section 118a (FIG. 6). As will be described in more detail below, the air duct system 110, and in particular the air duct assembly 116, is designed to be particularly light in weight, easily fabricated from relatively inexpensive materials, and can be at least partially collapsed for compact storage and/or shipping when not in use. These qualities reduce the cost of not just manufacturing, but also of shipping and installation, and also make it easier to handle the ductwork around a jobsite compared to ductwork made of more rigid and heavier materials. For example, advantages of rigid ductwork, such as the ability to achieve low-profile (low height) ducts, can still be realized while also providing compact storage configuration that is normally not achievable with rigid ductwork. Moreover, the ductwork can be readily cut-to-length or have duct sections joined end-to-end to provide longer duct runs, and can be installed, removed, collapsed, and expanded without the use of tools, or with the use of only basic hand tools.

Ventilated air duct assembly 116 can include multiple duct sections 118a, 118b that are connected end-to-end such as shown in FIGS. 9 and 12. The duct sections 118a, 118b may be identical to one another, and each includes an upper panel 120 having opposite side edges 120a, 120b; a lower panel 122 having opposite side edges 122a, 122b; and a pair of opposite side panels 124 having respective upper edges 124a and lower edges 124b. It will be appreciated that throughout the specification and claims, the terms “upper”, “lower”, and “sides” are used to facilitate understanding of the illustrated embodiments with reference to their relative positions and orientations the drawings, and are not intended to be limiting since the duct sections 118a, 118b and other components of air duct system 110 could be oriented differently such that different directional terms would apply. In the illustrated embodiment, lower panels 122 are formed with a series of air outlet openings 126 (FIGS. 9-10A), though it will be appreciated that any desired number and arrangement of openings may be formed in any one or more of the panels to achieve airflow in desired directions and locations.

The upper edges 124a of the side panels 124 are hingedly coupled to respective opposite side edges 120a, 120b of the upper panel 120, and the lower edges 124b of the side panels 124 are hingedly coupled to respective opposite side edges 122a, 122b of the lower panel 122 (FIGS. 9-10A). Panels 120, 122, 124 may be formed of single-layer resinous plastic sheets or corrugated (multi-layer) resinous plastic sheets, such that the resulting hinge couplings 128 may be formed as “living hinges” in which the resinous plastic sheet material itself serves as the hinge connections, and the various panels and their joining hinge couplings are all formed from a unitary sheet. Such sheets are typically made of polypropylene or polyethylene. These materials are chemical-resistant, water-proof, corrosion-proof, do not promote growth of mildew or microbes, and are readily cleanable. Other materials with desirable properties for a given application may be substituted for resinous plastic sheets.

Referring to FIG. 13, one of the duct sections 118a is shown to have opposite edge regions at one of the side edges 120b of upper panel 120, and at upper edge 124a of one of the side panels 124. In FIGS. 14A-14D, the duct section 118a is shown to have opposite edge regions overlapping and bonded together along the left-hand side. These overlapping edge regions (at upper-right in FIG. 13, and at left in FIGS. 14A-14D) may be bonded together with adhesive, or may be secured using other methods such as push-fasteners, threaded fasteners, adhesive bonding, heat welding, ultrasonic welding, staples, rivets, magnets, or the like.

The duct sections 118a, 118b are configurable between an expanded use configuration having a generally rectangular cross section (FIGS. 9-10A and 12-14A), and a generally flat storage configuration (FIG. 14D), by being collapsed through parallelogram shapes (FIGS. 14B and 14C), so that the upper panel 120 and one of the side panels 124 lie atop the lower panel 122 and the other side panel 124 as shown in FIG. 14D. Because of the resilience of the hinge couplings 128, each duct section 118a, 118b may not lie entirely flat with upper panel 120 lying fully against lower panel 122 in the manner shown in FIG. 14D, unless some pressure is applied to push them fully together, such as when multiple duct sections are packed together in a box for shipping or storage.

In the illustrated embodiment of FIGS. 9-10A, open end portions of first duct sections 118a are sleeved over the open end portions of second duct sections 118b. It will be appreciated that a similar coupling may be used to couple the first duct sections 118a to the respective outlets 114b of the air housings 114. If the materials of duct sections 118a, 118b are sufficiently resilient, this “sleeving” connection may be accomplished simply by manual force, and the couplings optionally secured with adhesive tape or other methods. Alternatively, and with reference to FIGS. 12 and 15-18, a duct junction 130 has a generally rectangular cross section corresponding to the generally rectangular cross sections of the duct sections 118a, 118b when they are in their expanded use configurations. The duct junction 130 has opposite end portions 130a, 130b that are sized and shaped with outer surfaces 132 that correspond to inner surfaces 134 of the duct sections 118a, 118b at their open ends. The duct junction's end portions 130a, 130b are insertable into the open ends of the duct sections 118a, 118b, and may be at least temporarily secured using adhesive tape or other methods.

Optionally, the duct junction 130 includes a diffuser plate 136 disposed between the opposite end portions 130a, 130b (FIGS. 16 and 18). The diffuser plate 136 provides enhanced mixing of gases that pass through its openings, and can be used to increase backpressure in an upstream duct section. The diffuser plate 136 may be replaced with a solid plate (not shown) to entirely block airflow through the duct junction 130. In the illustrated embodiment of FIGS. 12 and 15-18, duct junction 130 has a perimeter ridge 138 that extends outwardly from the outer surfaces 132 of the respective end portions 130a, 130b. Perimeter ridge 138 may have outer dimensions that are approximately the same as the outer dimensions of the duct sections 118a, 118b so that perimeter ridge 138 serves as a shoulder or stopping surface when duct junction 130 is inserted into one of the duct sections 118a, such as shown with broken-line arrows in FIG. 12. Perimeter ridge 138 thus allows an installer to easily install one end portion 130a, 130b of the duct junction 130 halfway into one of the duct sections 118a, 118b before sliding the other end portion of the duct junction into the other duct section. Each end-to-end connection of a pair of duct sections 118a, 118b can thus be made consistently with a respective end portions 130a, 130b of the duct junction 130 inserted equally into the duct sections 118a, 118b. In the illustrated embodiment of FIGS. 12 and 15-18, duct junction 130 is made from a unitary (single) piece of injection-molded resinous plastic.

Other types of duct junction are envisioned, such as a collapsible outer sleeve duct junction 230 that, in the illustrated embodiment of FIGS. 19-23 is made from a unitary piece of corrugated (also called “fluted”) plastic sheet material and constructed in a similar manner as the duct section 118a of FIG. 13, including a pair of overlapping edge regions that are secured together as best shown in FIGS. 21 and 23. Therefore, the outer sleeve junction 230 may be collapsible in the same manner as the duct section 118a of FIGS. 13-14D. Unlike duct junction 130 with end portions 130a, 130b that insert into respective open ends of the duct sections 118a, 118b, outer sleeve junction 230 is sized and shaped to slide over the outer surfaces of the duct sections 118a, 118b, as shown in FIGS. 19-20A and 23. Once outer sleeve duct junction 230 is pushed approximately halfway onto an open end of one of the duct sections 118a, it may be secured there with screw-fasteners 232a (FIGS. 19A and 20A) or push-fasteners 232b (FIG. 23), the latter typically being made of resinous plastic and have relatively wide heads 234 that remain along an outer surface of duct junction 230 after respective shaft portions 236 are pushed through the panel materials of both duct junction 230 and duct section 118a. Push-fasteners 232 are commonly available and may have pointed tips of shaft portions 236 for establishing their own insertion holes with the application of enough force, or may be inserted through pre-formed holes in the duct junction 230 and duct sections 118a,b. The shaft portions 236 have angled flexible teeth 238 (FIG. 23) that allow for insertion but resist pull-out. In practice, the duct junction 230 may be expected to also bow outwardly when the duct sections 118a,b are pressurized, but to a lesser degree than the duct sections at least in part because of reinforcing wires or rods 240 (FIG. 21), described below.

Optionally, and as shown in FIG. 21, reinforcing wires or rods 240 may be inserted into an interior of the corrugated plastic panel that forms duct junction 230. The reinforcing wire or rod 240 may be inserted along substantially the full width of the corrugated plastic panel while it is still generally planar in shape, and then bent with the plastic panel into the final shape of duct junction 230. The reinforcing wire or rod 240 allows duct junction 230 to better holds its shape, and therefore better holds the shape of the duct sections 118a,b to which it is attached. Optionally, a reinforcing wire or rod may be disposed around an exterior of the duct junction 230. By reinforcing the duct junction 230, the duct junction can more readily resist expanding or swelling outwardly when the fan 112, 112′ is energized and directing air or other gases into the duct sections 118a,b. This also improves the seal between the duct sections 118a,b and the duct junction 230, because in a non-pressurized and non-swollen state there may be notable gaps between the interior surfaces of the duct junction 230 and the exterior surfaces of the duct sections 118a,b. Because duct junction 230 may not be subject to interior air pressure like duct sections 118a,b, duct junction it will not expand to the same degree as the duct sections 118a,b (which can be envisioned with reference to FIGS. 22 and 23), and therefore the duct sections 118a,b may be expected to expand against the interior of duct junction 230, reducing or eliminating air gaps in the process. This effect may be more pronounced when duct junction 230 is reinforced or made of a more rigid material. In FIGS. 22 and 23 are shown one of the duct sections 118a in a swollen pressurized configuration, with one of its open ends held to a rectangular shape by one of the duct junctions 230. It should be appreciated that the duct junction 230 is shown in FIG. 23, but it is omitted from FIG. 22 in which the shape of the duct section 118a is illustrated in a pressurized state as if the duct junction were installed.

Referring to FIGS. 19 and 24-26, an end cap 250 may be installed at an open end of the duct section 118b that is farthest from the fan 112, 112′. End cap 250 may be made from the same corrugated sheet material as the duct sections 118a,b and/or the duct junction 230, or from a more malleable or moldable material that is formable to the desired shape. End cap 250 is generally rectangular in shape (FIGS. 25 and 26), with a main rectangular panel 252 having dimensions that generally correspond to the duct sections 118a,b, a pair of side flaps 254, and a pair of upper and lower flaps 256 that can be bent or formed away from the rectangular panel 252. End cap 250 may be formed from a flat panel (FIG. 24) and sized to fit over an open end of the duct section 118b such as shown in FIG. 26, with upper and lower flaps 256 fitted over the duct section's upper panel 120 and lower panel 122, and with side flaps 254 fitted over the duct section's opposite side panels 124. End cap 250 can be secured with screw fasteners 232a (shown) or with push-fasteners 232b, and may operate in a similar constraining manner as duct junction 230 by sleeving over the end of the duct section 118b and constraining its expansion while pressurized with a flow of air or other gases. Any gaps between end cap 250 and duct section 118b may be reduced when the duct section 118b is pressurized.

Optionally, duct sections 118a,b may be suspended or retained along grow rack system 100 by a set of hangers 260 that have central bite portions 262 with a length generally corresponding to (or somewhat longer than) the width of each duct section 118a,b, upright legs 264 each with a length generally corresponding to (or somewhat longer than) the height of each duct section 118a,b, and with outwardly-angled hook portions 266 for engaging end support beams 106, side support beams 104, or other structures associate with shelves 108a, 108b. Hangers 260 may be formed of resilient metal wire, for example, and readily flexed during installation so that hook portions 266 may be engaged with other structures of rack system 100, preferably without use of tools, and disengaged in a similar manner.

Therefore, the ventilated air duct system 110 provides a relatively inexpensive, light weight, easy-to-handle, and easy-to-setup duct arrangement that is well suited for indoor growing operations, although it will be appreciated that other applications are equally possible. The duct sections may be cut-to-length with a tool as simple as a box cutter or knife, multiple sections may be readily joined together to obtain longer overall lengths, and once the duct junctions are removed the duct sections may be readily collapsed for storage or shipping, or expanded for use, although some duct junctions may allow the duct sections to be at least partially collapsed while the duct junctions remain installed. Assembly and mounting may be accomplished using only very basic tools, or in some cases with no tools at all. The resulting ductwork can be very light weight and provide a combination of benefits normally found in only rigid ducts or only fabric ducts. Because of its typical low weight, supporting the ducts along the length of a rack can be accomplished with basic light-duty hardware such as hanger brackets or wires, or even adhesive tape.

Optionally, and with reference to FIGS. 11A and 11B, the duct sections 118a may be coupled to an air housing 214 having a pair of air inlets 214a (each of which may receive a fan, not shown) along a top panel thereof, and a pair of air outlets 214b along a side panel thereof. Upstream duct sections 118a may be directly or indirectly coupled to respective air outlets 214b which, in the illustrated embodiment of FIGS. 11A and 11B, are fitted with removable air diffusers 216 that provide flow restriction and increase turbulence in the airflow for improved mixing, such as if carbon dioxide or other supplemental gas is being added to the air being drawn into the air housing 214. Supplemental carbon dioxide systems are more fully described in commonly-owned U.S. Pat. Nos. 11,607,041; 11,632,915; 11,641,810; and 11,686,107, all of which are hereby incorporated herein by reference in their entireties.

Fans 12 and air housings 114, 214, 314 may be mounted within a rack volume defined by the plurality of uprights 102, or they may be mounted outside of the rack volume defined by the plurality of uprights 102, such as shown in FIGS. 1-3. More detailed descriptions of rack-based plant growing systems are described in commonly-owned U.S. Pat. Nos. 11,641,810 and 11,632,915. It should also be appreciated that the ventilated air duct system 110, including collapsible duct sections 118a, 118b, may be adapted into other air systems such as those described in commonly-owned U.S. Pat. No. 11,582,920, which is hereby incorporated herein by reference in its entirety.

Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents.

Claims

1. A ventilated air duct assembly comprising:

first and second duct sections, each of said duct sections comprising: an upper panel having opposite side edges; a lower panel having opposite side edges; and a pair of opposite side panels having upper and lower edges; wherein said upper edges of said side panels are hingedly coupled to respective ones of said opposite side edges of said upper panel, and said lower edges of said side panels are hingedly coupled to respective ones of said opposite side edges of said lower panel; wherein at least one of said panels defines a plurality of air outlet openings; wherein said first and second duct sections are configurable between an expanded use configuration having a generally rectangular cross section and a generally flat storage configuration in which a first of said opposite side panels and a portion of said upper panel lie against said lower panel, and another portion of said upper panel lies against a second of said opposite side panels;

a duct junction having a generally rectangular cross section corresponding to said generally rectangular cross sections of said first and second duct sections in said expanded use configuration;

wherein said duct junction comprises opposite open ends that are configured to engage respective open ends of said first and second duct sections in said expanded use configuration, to secure said first duct section to said second duct section in fluid communication with one another.

2. The ventilated air duct assembly of claim 1, wherein said duct junction comprises a diffuser plate disposed between said opposite open ends.

3. The ventilated air duct assembly of claim 1, wherein an outer surface of said duct junction comprises a ridge projecting outwardly therefrom, said ridge arranged between and generally parallel to said opposite open ends, wherein said opposite open ends of said duct junction are insertable into said open ends of said first and second duct sections so that said first and second duct sections each abut an opposite side of said ridge.

4. The ventilated air duct assembly of claim 3, wherein said ridge comprises a rectangular ridge projecting outwardly around the entire periphery of said duct junction.

5. The ventilated air duct assembly of claim 1, wherein said duct junction comprises a unitarily-formed injection-molded resinous plastic.

6. The ventilated air duct assembly of claim 1, wherein said duct junction comprises:

an upper panel having opposite side edges;

a lower panel having opposite side edges; and

a pair of opposite side panels having upper and lower edges;

wherein said upper edges of said duct junction side panels are hingedly coupled to respective ones of said duct junction opposite side edges of said duct junction upper panel, and said duct junction lower edges of said duct junction side panels are hingedly coupled to respective ones of said duct junction opposite side edges of said duct junction lower panel.

7. The ventilated air duct assembly of claim 6, wherein said duct junction comprises interior dimensions corresponding to exterior dimensions of said first and second duct sections, and wherein said duct junction in said expanded use configuration is sized and shaped to sleeve over said respective open ends of said first and second duct sections in their expanded use configuration.

8. The ventilated air duct assembly of claim 6, wherein said duct junction is configurable between an expanded use configuration having a generally rectangular cross section and a generally flat storage configuration in which a first of said opposite duct junction side panels and a portion of said duct junction upper panel lie against said duct junction lower panel, and another portion of said duct junction upper panel lies against a second of said opposite duct junction side panels.

9. The ventilated air duct assembly of claim 1, wherein said duct junction comprises corrugated plastic sheet material.

10. The ventilated air duct assembly of claim 9, wherein said duct junction comprises a metal reinforcement wire disposed inside of said corrugated plastic sheet material.

11. The ventilated air duct assembly of claim 9, wherein said duct junction comprises a single sheet of said corrugated plastic material having opposite edge regions secured together.

12. The ventilated air duct assembly of claim 11, wherein said opposite edge regions are secured together with at least one chosen from push-fasteners, threaded fasteners, adhesive bonding, heat welding, ultrasonic welding, staples, rivets, and magnets.

13. The ventilated air duct assembly of claim 12, wherein said opposite side edge regions overlap one another.

14. The ventilated air duct assembly of claim 1, wherein said panels of said first and second duct sections comprise corrugated plastic sheet material.

15. The ventilated air duct assembly of claim 14, wherein said first and second duct sections each comprise a single sheet of said corrugated plastic material having opposite edge regions secured together.

16. The ventilated air duct assembly of claim 15, wherein said opposite edge regions overlap one another and are secured together with at least one chosen from push-fasteners, threaded fasteners, adhesive bonding, heat welding, ultrasonic welding, staples, rivets, and magnets.

17. The ventilated air duct assembly of claim 1, wherein said hinged couplings comprise living hinges of resinous plastic.

18. A ventilated air duct system comprising:

said ventilated air duct assembly of claim 1;

an air housing having an inlet and an outlet;

a fan fluidly coupled to said inlet; and

an end cap coupled to an end of said second duct section opposite said duct junction;

wherein said first duct section is fluidly coupled to said outlet of said air housing.

19. The ventilated air duct system of claim 18, further in combination with a grow rack system having at least one shelf supported by a plurality of uprights.

20. The ventilated air duct system of claim 19, wherein said ventilated air duct assembly is supported along said grow rack system and extends from one pair of said uprights to an opposite pair of said uprights.