Abstract:
A retractable high-reflectivity wall provides improved lighting conditions for growing plants. The wall is retractable, so that it does not get in the way when the user wishes to work in the grow area. The wall can also be retracted so that it is easier to move, carry, reposition, resize, and/or remove as needed. The wall may be implemented as a sheet including a reflective surface adhered or otherwise mounted onto a flexible backing such as a vinyl surface for additional support/reinforcement. The resulting flexible reflective wall is mounted onto a roller assembly which allows the wall to be extended or retracted. A support bar can be affixed to the roller assembly via brackets or other hardware. The entire apparatus can be suspended from or affixed to a ceiling, wall, fixture, or other object, or it can be supported by a stand or other assembly.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority from U.S. Provisional Application No. 61/252,439, for “Retractable Reflective Wall,” filed on Oct. 16, 2009, which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to reflective surfaces for enhancing light sources in plant growing areas. 
         [0004]    2. Description of the Related Art 
         [0005]    One of the challenges in indoor agriculture is ensuring that plants receive sufficient light. Reflective walls or screens can be used to improve efficiency by directing light from a natural or artificial light source to the grow area. Stray light that would otherwise be wasted is thereby reflected toward the plants. 
         [0006]    Fixed, or stationary, reflective walls can become dirty when the user works in the grow area. For example, when the plants are sprayed externally with water or chemicals, the spray can accumulate on the reflective surface, causing the wall to lose reflectivity. This results in a net loss of light to the plant. Replacement of a fixed reflective wall can be expensive, cumbersome, and/or difficult. 
         [0007]    Some growers use a reflective surface mounted onto Styrofoam or wood boards that can be moved or removed as needed. The reflective surface can thereby be removed from the grow area when the user is working, and can be reinstalled when the user is finished working. However, movement of these large boards can be cumbersome, and it may be difficult to find adequate storage for the boards when they are not in use. 
         [0008]    Some growers use stationary reflective fabric material for the grow area walls; this material can be readily cleaned, but it generally fails to provide adequate reflective properties, and still requires periodic maintenance in the form of cleaning. 
       SUMMARY OF THE INVENTION 
       [0009]    According to various embodiments of the present invention, a retractable high-reflectivity wall is provided. The wall may be free-standing and/or supported by a stand, so that it does not rely on any external surfaces or objects for support. Alternatively, the wall may be suspended from a ceiling, fixture, hook, door, or other element. The wall is retractable, so that it does not get in the way when the user wishes to work in the grow area. By retracting the wall, the user can ensure that the wall does not get dirty when the user works. The wall can also be retracted, either manually or by automatic means such as a spring, motor, or other mechanism. Retraction of the wall allows it to be more easily moved, carried, repositioned, resized, and/or removed as needed. The wall of the present invention thus provides distinct advantages over prior art systems in which a reflective wall has a fixed position and/or is difficult to move. 
         [0010]    In one embodiment, the retractable wall is provided as a reflective surface adhered or otherwise mounted onto a flexible backing such as a vinyl surface for additional support/reinforcement. The resulting flexible reflective wall is mounted onto a roller assembly which allows the wall to be extended or retracted. A support bar can be affixed to the roller assembly via brackets or other hardware. The entire apparatus can be suspended from or affixed to a ceiling, wall, fixture, or other object, and/or it can be supported by a stand or other assembly. In one embodiment, hooks in the support bar can be used for suspending the apparatus via twine, rope, wire, or the like. In another embodiment, brackets or other attachment hardware on the support bar can be used to affix the apparatus to a wall, ceiling, or the like. In one embodiment, the retractable wall includes a spring-loaded self-retracting feature; a chain or cord can be used to activate a friction brake to control the self-retracting feature. In other embodiments, a motorized mechanism can be used for extension and/or retraction of the wall. 
         [0011]    The various embodiments of the present invention thus provide a reflective wall that avoids the problems and limitations of prior art reflective walls. In various embodiments, the reflective wall of the present invention can be easily moved, reconfigured, and/or stored, and provides a mechanism for limiting exposure of the reflective surface to dirt, water, and chemicals that can diminish its effectiveness. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The accompanying drawings illustrate several embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
           [0013]      FIG. 1A  is a diagram depicting a retractable reflective wall in a partially retracted state, according to one embodiment of the present invention. 
           [0014]      FIG. 1B  is a diagram depicting a retractable reflective wall in a substantially extended state, according to one embodiment of the present invention. 
           [0015]      FIG. 2  is a diagram depicting the use of two retractable reflective walls in an indoor agriculture setting. 
           [0016]      FIG. 3  is a detail diagram depicting an example of a fastening clip for affixing the bottom of the retractable reflective wall to an object or surface, according to one embodiment. 
           [0017]      FIG. 4  is an oblique view of a retractable reflective wall having a self-retracting feature, the wall being in a retracted state, according to one embodiment of the present invention. 
           [0018]      FIGS. 5 and 6  are detail oblique views of a retractable reflective wall having a self-retracting feature, the wall being in a retracted state, according to one embodiment of the present invention. 
           [0019]      FIG. 7  is a detail cutaway view depicting a retractable reflective wall having a self-retracting feature, according to one embodiment of the present invention. 
           [0020]      FIG. 8  is a detail exploded view depicting components of a retractable reflective wall having a self-retracting feature, according to one embodiment of the present invention. 
           [0021]      FIG. 9  is a flow diagram depicting a method of using a retractable reflective wall, according to one embodiment of the present invention. 
           [0022]      FIG. 10  is diagram depicting a retractable reflective wall having a chain retractor, the wall being in a partially retracted state, according to one embodiment of the present invention. 
           [0023]      FIG. 11  is a detail view depicting a retractable reflective wall having a chain retractor, according to one embodiment of the present invention. 
           [0024]      FIG. 12  is a cutaway view depicting a retractable reflective wall having a chain retractor, according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0025]    The present invention is now described more fully with reference to the accompanying Figures, in which several embodiments of the invention are shown. The present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather these embodiments are provided so that this disclosure will be complete and will fully convey the invention to those skilled in the art. 
         [0026]    In the following description, the invention is set forth as a retractable reflective wall suitable for use in providing light for growing plants. However, one skilled in the art will recognize that the invention can be implemented in other ways as well. For example, the retractable reflective wall can be used for other purposes and in other contexts. It will be apparent from the description provided herein that many other variations are possible, and that the particular embodiments set forth herein are intended to be exemplary and not limiting. 
         [0027]    Referring now to  FIG. 1A , there is shown retractable reflective wall  100  in a partially retracted state, according to one embodiment of the present invention. Support beam  102 , which may be constructed of wood, plastic, metal, or any other material, can be suspended from a ceiling, wall, fixture, or other object (not shown), or it can be supported by a stand or other assembly (not shown), or is supported in some other way to allow it to be positioned above the grow area. For example, hooks  109  may be used for hanging beam  102  from a ceiling using twine  110 , wire, string, rope, or the like. Brackets  108  may also be provided, in addition to or instead of hooks  109 , to affix the apparatus to a wall, ceiling, or the like. One skilled in the art will recognize that other mechanisms may be used for supporting the assembly. 
         [0028]    Brackets  107  attached to ends of support beam  102  hold spring-loaded roller assembly  106  in a manner that permits rotation of roller assembly  106  about an axis, so as allow the reflective wall of the present invention to be extended or retracted. Flexible sheet  131  is mounted onto roller assembly  106 . 
         [0029]    Referring also to  FIG. 1B , there is shown retractable reflective wall  100  in a substantially extended state, according to one embodiment of the present invention. The apparatus of  FIG. 1B  is similar to that of  FIG. 1A , except that support beam  102  is replaced by housing  121 , which forms an outer shell surrounding and supporting roller assembly  106 . Housing  121  may be constructed of plastic, wood, metal, or any other suitable material. In some embodiments, housing  121  may be preferable to support beam  102 , as it hides roller assembly  106  and may therefore provide cosmetic advantages.  FIG. 1B  also depicts supports  122  in lieu of hooks  109 , for attachment to twine  110 . One skilled in the art will recognize that any support mechanism can be used. 
         [0030]    In one embodiment, sheet  131  includes a highly reflective mirrored surface  101  that can be used to reflect light toward a grow area when extended from roller assembly  106 . Reflective surface  101  can be on one or both sides of sheet  131 . In one embodiment, reflective surface  101  is implemented using an aluminized plastic or polyester film such as Mylar®. In one embodiment, reflective surface  101  is formed or textured in order to provide better scattering of reflected light. Reflective surface  101  can be adhered or otherwise mounted onto a flexible backing such as a vinyl surface for additional support and reinforcement. 
         [0031]    In one embodiment, roller assembly  106  includes a ratcheting spring assembly, similar to that found in a roller-type window blind, which allows sheet  131  to be extended and retracted as desired. In one embodiment, sheet  131  can be rolled or unrolled fully and/or partially to any desired extent, and can be configured to lock into any desired position. In one embodiment, a spring mechanism within the roller assembly provides for automatic retraction, for example if the user tugs on and then releases the bottom edge of sheet  131 . In one embodiment, motorized extension and retraction of sheet  131  can also be implemented, for example by providing an electric motor (not shown) for rotating roller assembly  106  in either direction. Internal components of roller assembly  106  are described in more detail below in connection with  FIGS. 7 and 8 . 
         [0032]    In another embodiment, a chain or cord can be provided for retracting sheet  131 , as described in more detail below in connection with  FIGS. 10 to 12 . 
         [0033]    One skilled in the art will recognize that retractable reflective wall  100  of the present invention can have any desired dimensions, depending on the length of support beam  102  and the dimensions of sheet  131 . In one embodiment, the width of sheet  131  is between 2 and 8 feet, although any width can be provided. In one embodiment, the length of sheet  131  when fully extended is 55 inches, although any length can be provided. 
         [0034]    In one embodiment, sheet  131 , when extended, hangs from roller assembly  106 . Rod  105  (or another type of weight) can be affixed to the bottom edge of sheet  131  so as to improve stability and limit movement resulting from wind, drafts, or other factors. 
         [0035]    In one embodiment, a fastening mechanism, such as pull-down fasteners  104 , can be provided to allow the bottom of sheet  131  to be affixed to a suitable object or surface; for example, fasteners  104  can attach to grommets  103  along the bottom edge of sheet  131 , and can include hooks  111 , clips, or other similar devices that attach to any suitable object or surface, such as the perimeter of a grow tray, or, in some cases, to the grow room floor itself. A cord or wire can be used to provide extended reach between the bottom edge of sheet  131  and the surface to which it is affixed. To retract sheet  131 , connecting hooks  111  are disengaged either from the bottom edge of sheet  131  or from the surface or object to which hooks  111  are attached. Connecting hooks  111  or clips can reside on the bottom edge of sheet  131  itself or on the tray or other surface, with connection points being located so as to engage connecting hooks  111  or clips. 
         [0036]    In various embodiments of the invention, the described pull-down fasteners  104  may be provided instead of or in addition to rod  105  or other weighting mechanism. Such a mechanism anchors retractable reflective wall  100  in its extended position. 
         [0037]    Retractable reflective wall  100  can thus be free-standing when in its extended position, so that the surface of retractable wall  100  need not be situated against a window, fixed wall, or other surface. Referring now also to  FIG. 2 , there is shown an arrangement in which two retractable reflective walls  100  are used in an indoor agriculture setting.  FIG. 2  illustrates the use of the techniques of the present invention to implement retractable reflective walls  100  that can be situated in a free-standing manner surrounding a grow tray  204  or other grow area, without the need for any window, fixed wall, or other surface adjacent to or behind retractable reflective walls  100 . 
         [0038]    In  FIG. 2 , the two reflective walls  100  are situated so that they reflect light from lamp  201  onto plant(s)  203  growing in grow tray  204 . The user can retract walls  100  when he or she wishes to work with plant(s)  203 , such as to water them, so as to avoid damaging or soiling walls  100 . Fasteners  104  affixed the bottom edge of sheet  131  to grow tray  204  for added stability, as described above.  FIG. 2  also depicts vinyl backing  202  that can be provided as part of sheet  131  for additional strength and durability. 
         [0039]    Referring now to  FIG. 3 , there is shown a detail diagram depicting an example of fastening clip  104 . Clip  104  affixes the bottom edge of sheet  131  of retractable reflective wall  100  to an object or surface, according to one embodiment. In the example, clip  104  is attached to grommet  103  of sheet  131 , and includes hook  111  which attaches to an edge of grow tray  204 . 
         [0040]    Referring now to  FIGS. 4 through 6 , there are shown oblique views of retractable reflective wall  100  in a retracted state, from various points of view, according to one embodiment of the present invention. As can be seen from  FIGS. 4 through 6 , beam  102  can be constructed from an extruded piece  513 , with caps  515  affixed to either end. In one embodiment, supports  122  and brackets  107  are attached to extruded piece  513 . Brackets  107  hold roller assembly  106 , which includes a cylinder and inner axle (not shown in  FIGS. 4 through 6 ) and end caps  402 . Sheet  131  is rolled onto the cylinder between end caps  402 . 
         [0041]    Referring now to  FIG. 7 , there is shown a cutaway view depicting retractable reflective wall  100  having a self-retracting feature, according to one embodiment of the present invention. Referring also to  FIG. 8 , there is shown an exploded view depicting components of retractable reflective wall  100  having a self-retracting feature, according to one embodiment of the present invention.  FIGS. 7 and 8  depict a particular internal structure that can be used in one embodiment for implementing the self-retracting feature, although one skilled in the art will recognize that other structures and arrangements may be used. Cylinder  701  contains inner axle  707  as well as spring  711 . Spring  711  is held in place by collar  710 , which may include caps at either end to keep spring  711  from sliding off. Spring  711  is compressed when sheet  131  is extended. Spring  711  exerts rotational force tending to cause cylinder  701  to rotate in a direction that will retract sheet  131 . Cog catch  805  is used, in one embodiment, to keep spring&#39;s  711  compression from rotating cylinder  701  when sheet  131  is extended. When user tugs on sheet  131 , cog catch  805  is released; spring&#39;s  711  compression then causes cylinder  701  to rotate so as to automatically retract sheet  131 . 
         [0042]      FIG. 8  depicts additional components that are used in one embodiment. Shoulder screws  804  hold inner axle  707 , cap  402 , and cylinder  701  in place. Washer  808  permits rotational movement of inner axle  707  with respect to cap  402 . Also depicted in  FIG. 8  is weighted rod  821 , which may be affixed to or inserted into sheet  131 , for example at a bottom edge. 
         [0043]    Referring now to  FIG. 10 , there is shown an embodiment in which retractable reflective wall  100  has a chain retractor. Referring now also to  FIG. 11 , there is shown a detail view depicting the chain retractor embodiment. Referring now also to  FIG. 12 , there is shown a cutaway view depicting the chain retractor embodiment. 
         [0044]    In one embodiment, the embodiment depicted in  FIGS. 10 through 12  operates as follows. Retractable wall  100  includes brake assembly  1001  for selectively holding sheet  131  in the extended position (or in a partially extended position) while allowing for automatic retraction when the user pulls on ball chain  1012 . Brake assembly  1001  includes cone  1206 , cone socket  1207 , cone axle  1208 , pull lever  1111 , and end-cap port  1115 . Spring  1210  provides for automatic retraction of sheet  131  by exerting force that tends to rotate spring axle  1204 . Spring axle  1204  is connected to cone axle  1208  and cone  1206 ; friction between cone  1206  and cone socket  1207  prevents spring axle  1204  from rotating when brake assembly  1001  is engaged. The user disengages brake assembly  1001  by pulling on chain  1012 ; this causes pull lever  1111  to rotate in a downward direction against end-cap port  1115 , pulling on spring axle  1204  and causing cone  1206  to disengage gradually from cone socket  1207 . This brake mechanism allows the user to control the rate at which sheet  131  retracts, by maintaining any desired degree of friction between cone  1206  and cone socket  1207 . The user can release chain  1012  at any time to re-engage brake assembly  1001  and thereby hold sheet  131  in any desired position, whether fully extended, fully retracted, or partially extended. 
         [0045]    End cap  515  may optionally be provided to cover and/or hide the internal components of brake assembly  1001 . Any type of chain, cord, wire, rod, or similar implement can be used in place of ball chain  1012 . 
         [0046]    In other embodiments, motorized and/or other mechanical means can be used for extending and/or retracting sheet  131 . 
         [0047]    Referring now to  FIG. 9 , there is shown a flow diagram depicting a method of using a retractable reflective wall  100 , according to one embodiment of the present invention. The user positions  901  retractable reflective wall  100  as desired. Retractable reflective wall  100  can be secured at the desired position, for example by attachment to a wall, ceiling, or fixture, or by suspension via wire, cord, twine, or the like. The user extends  902  wall  100  so as to expose sheet  131  so that reflective surface  101  reflects light onto the grow area. Extension  902  of wall  100  can be performed, for example, by pulling down on sheet  131  so that it unrolls from roller assembly  106 , or by some other mechanism. In one embodiment, wall  100  is held in the extended position by cog catch  805 , and/or by brake assembly  1001 , and can be further stabilized by the use of weighted rod  105 , pull-down fasteners  104 , and/or other components. One skilled in the art will recognize that steps  901  and  902  can be performed in any sequence; for example, reflective wall  100  can be extended  902  prior to positioning  901  of reflective wall  100 . In addition, adjustments to the position of reflective wall  100  can be made at any time. 
         [0048]    Plants  203  in the grow area can now be exposed  903  to light from a source such as lamp  201 . Wall  100  serves to reflect light toward the grow area. If the user wishes to work in the grow area and/or to move wall  100 , he or she retracts  904  wall  100 . As described above in connection with  FIGS. 4 through 8 , in one embodiment, wall  100  can be self-retracting, so that retraction  904  is initiated by tugging on the bottom edge of sheet  131 , causing cog catch  805  to release and allowing spring  711  to rotate cylinder  701 . Alternatively, as described above in connection with  FIGS. 10 through 12 , the user can pull on chain  1012  to reduce friction between the components of brake assembly  1001 , thus allowing spring  1210  to rotate spring axle  1204  and thereby retract sheet  131 . Other mechanisms can be used for extension and retraction of sheet  131 ; for example in yet another embodiment, two chains or cords can be provided; pulling on one causes sheet  131  to be extended, and pulling on the other causes sheet  131  to retract. 
         [0049]    Once sheet  131  has been retracted, the user can work  905  with plants  203  in the grow area, move plants  203 , and/or reposition wall  100 . If the user wishes to re-expose the grow area to light, the method returns to step  902 . 
         [0050]    Retractable reflective wall  100  of the present invention has numerous advantages over prior art techniques. It has the ability to retract into a small compact unit for ease of storage, movement, and/or reconfiguration. When in use, it expands into a large highly-reflective surface for the purpose of redirecting grow light in an agricultural setting. 
         [0051]    In addition, the retracting feature makes retractable reflective wall  100  ideal for working in a grow area, as one can retract sheet  131  while working or while plants are being sprayed, then pull sheet  131  back down to its extended position when finished working. Thus, accumulation of dirt, water, or other chemicals on reflective surface  101  can be avoided or reduced. 
         [0052]    In the above description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to one skilled in the art that the invention can be practiced without these specific details. In other instances, structures and devices are shown in block diagram form in order to avoid obscuring the invention. 
         [0053]    Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment. 
         [0054]    As will be understood by those familiar with the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, the particular architectures depicted above are merely exemplary of one implementation of the present invention. In one embodiment, the device of the present invention can be used for functions other than for providing light to a grow area. 
         [0055]    The functional elements and method steps described above are provided as illustrative examples of one technique for implementing the invention; one skilled in the art will recognize that many other implementations are possible without departing from the present invention as recited in the claims. Likewise, the particular capitalization or naming of the modules, protocols, features, attributes, or any other aspect is not mandatory or significant, and the mechanisms that implement the invention or its features may have different names or formats. In addition, the present invention may be implemented as a method, process, user interface, computer program product, system, apparatus, or any combination thereof. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.