Abstract:
A horticultural light fixture for reducing the temperature impact of the light source on growing plants, including a hollow sheet metal tube, having first and second round hollow ends and a cutaway portion on the underside open towards the plants with at least one lamp socket mounted within said metallic tube, locating the lamp over the cutaway portion, further including a reflector mounted within the metallic tube and extending out through the cutaway portion, constructed and arranged to deflect light from the lamp toward the plants, having a transparent portion fittingly attached to the reflector between the lamp and the plants being impermeable to the heated atmosphere while allowing light to pass through.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    None 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    This invention is not the product of any Federally Sponsored Research or Development. 
       REFERENCE TO MICROFICHE APPENDIX 
       [0003]    Not Applicable 
       BACKGROUND OF THE INVENTION 
       [0004]    1. Technical Field 
         [0005]    The present device relates generally to horticultural and agricultural lighting systems used in developing plants in controlled growing environments. 
         [0006]    2. Discussion of Related Art 
         [0007]    Indoor gardens, green houses, hydroponics systems, and isolated carbon dioxide growing chambers demand careful regulation of temperature, light, hydration, nutrients, and humidity. In these controlled environments, one of the major challenges is providing adequate light intensity, while efficiently removing the heat generated by the grow lamp. A second major challenge relates to the manufacturing of the system in an economical way, utilizing inexpensive and light materials. A third major challenge in operating a horticulture light system is keeping the grow lamp within optimum temperatures in order to promote longevity. 
         [0008]    Horticulture lighting systems depend on grow lamps as a primary light source. Commonly used grow lamps are high pressure sodium and metal halide. These grow lamps get exceptionally hot when confined in a small light fixture. The heat generated may curl new growth on plants, dry out the soil; and, if the heat is not dissipated, the grow lamp will have a reduced life span. These undesirable effects reduce yields and increase operational costs. 
         [0009]    Several air cooled horticulture light fixture designs incorporate sheet metal enclosures in combination with a transparent shield between the grow lamp and the developing plants. The sheet metal enclosures typically absorb considerable energy during operation and contaminate the growing environment with radiated heat. This problem of energy being absorbed and then radiated was addressed by U.S. Pat. No. 6,595,662 issued in July 2003 to Wardenburg disclosing an air cooled double walled fixture wherein cooling air was introduced via conduit on one end and exhausted out the other side, and a transparent portion was located between the grow lamp and the plants allowing for light to pass while isolating the fixture from the growing environment. However, Wardenburg did not disclose or teach the fixture having a tube design allowing for straight and continuous channel of air flow to maximize the cooling effect. 
         [0010]    U.S. Pat. No. 6,267,483 issued in July 2001 to Hembery discloses a straight and continuous channel of air flow through a transparent tube. The Hembery device isolates the grow lamp from the growing plants by centering the grow lamp within the transparent tube. Free flowing air enters one end of the fixture and free flows out the other side. The Hembery device absolutely depends on a transparent tube, and the transparent material of choice is borosilicate glass, which is heavy and expensive. 
         [0011]    U.S. Pat. No. 6,247,830 issued in June 2001 to Winnett et al. discloses a forced air transparent tube fixture that senses the temperature of the fixture and shuts the grow lamp down if the temperature exceeds a predetermined maximum safe operating level. The Winnett device also relies on a transparent tube that must withstand high temperatures. 
         [0012]    The tube design is desirable because of the straight channel flow of cooling atmosphere. The transparent tube designs of Hembery and Winnett allow for straight channel flow, but require a heavy and expensive tube usually made of borosilicate glass. The photometric performance of the transparent tube fixtures are lacking because of the curvature of the glass tube. A sheet metal tube combined with a flat transparent portion is more desirable as it is cheaper, weighs less, and allows light to pass through the flat surface with a minimum of distortion, deflection, and parasitic loss. Further, integration of a reflector maximizing the photometric performance is all but impossible with a glass tube because the reflector must be contained within the tube, or be attached externally to the tube. 
         [0013]    Not one of the above discussed inventions, taken either singularly or in combination, teaches the instant invention as claimed. What is desired is a lightweight, inexpensive, and efficient fixture that will minimally heat-impact the growing environment, while promoting longevity in the grow lamp by easily passing cooling atmosphere through the fixture. 
       OBJECTS AND ADVANTAGES 
       [0014]    There are several objects and advantages of the present device:
       a) to provide a horticulture light system that minimizes the heat impact of the grow lamp on the growing environment;   b) to provide a horticulture light system that allows for cooling atmosphere to be flowed into a hollow metallic tube, over the grow lamp in a straight and continuous channel, and out the other end of the hollow metallic tube to cool and promote longevity in the grow lamp;   c) to provide a thermally isolated horticulture light system that minimizes the heat contamination of the growing environment by exhausting the heated air easily through simple connection to round conduit;   d) to provide a sheet metal alternative to using a transparent tube;       
 
         [0019]    Still further objects and advantages will become apparent from considerations of the ensuing description and drawings. 
       SUMMARY 
       [0020]    In accordance with the present device, a horticulture light system constructed primarily of inexpensive and light sheet metal, providing straight channel flow of cooling atmosphere over the grow lamp and through the reflector area, exhausting out the other side; thus, thermally isolating the fixture from the growing plants. 
         [0021]    The grow lamp should be generally cylindrical in shape and smaller in diameter than the sheet metal tube and round hollow ends, thereby allowing for sufficient forced air flow over the grow lamp and through the reflector area. The sheet metal tube should be of adequate length to contain the grow lamp and the reflector be of size, shape, and location to reflect light towards the growing plants. The transparent portion should be flat and sized to match the aperture of the reflector. 
         [0022]    The round hollow ends may be sized to match commercially available conduit, thus allowing for easy connection to a closed loop forced atmosphere cooling system. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a perspective view of one embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture; 
           [0024]      FIG. 2  is a front side view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0025]      FIG. 3  is a left side view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0026]      FIG. 4  is a top view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0027]      FIG. 5  is a bottom side view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0028]      FIG. 6  is a component exploded view of the hollow sheet metal tube of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0029]      FIG. 7  is an exploded perspective view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 ; 
           [0030]      FIG. 8  is a perspective, side, top and end view of the hollow sheet metal tube as shown in  FIG. 1 ; 
           [0031]      FIG. 9  is a is a perspective, side, top and end view of the reflector as shown in  FIG. 1 ; 
           [0032]      FIG. 10  is a right side view of the embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0033]    Referring now to the drawings, and particularly to  FIGS. 1-10 , a preferred embodiment of the present device is shown, illustrating the Forced Air Cooled Metallic Tubular Horticulture Light Fixture used in developing plants in controlled growing environments. The exemplary embodiments according to the present device are illustrated with those components necessary to demonstrate the inventive design. Many of the necessary electrical and mechanical elements for attaching, powering, and implementing are not present. For example, the electrical service connection of 110 volts and 220 volts is known by one of normal skill in the art but not specifically mentioned. 
       Description FIG. 1: 
       [0034]      FIG. 1  illustrates one embodiment of the assembled device from a perspective view having a hollow sheet metal tube  100  fittingly attached to the reflector  130 . The hollow sheet metal tube  100  is preferred over a transparent tube because the hollow sheet metal tube  100  has heat shielding advantages while remaining lightweight and inexpensive. The reflector  130  reflects the light towards the plants and is thermally isolated from the growing environment by a transparent portion  108 . Said transparent portion  108  is sized according to the aperture of the reflector  130 , thus minimizing the amount of transparent material needed. Transparent materials are more expensive than sheet metal and tend to be heavier. Therefore, it is desirable to minimize the amount of transparent material used. 
         [0035]    The inventor overcame the need for a heavy and expensive transparent tube by constructing the tube portion of inexpensive sheet metal. The inventor then improved the photometric properties of the fixture by integrating the reflector  130  within the hollow sheet metal tube  100 , accomplishing the thermal isolation of the heated air with a transparent portion  108  that could be flat and thin; and, thus, reducing the overall cost and weight of the device. The transparent portion  108  can be constructed from inexpensive flat tempered glass and sized to match the reflector aperture, thus minimizing the amount of transparent material needed. Although flat tempered glass is preferred, the transparent portion  108  may be constructed from any material that can withstand the temperatures produced by the grow lamp, while allowing light to pass through to the growing plants. 
         [0036]    In the preferred embodiment, said hollow sheet metal tube  100  is constructed from a single sheet of metal having a first round hollow end  102  and a second round hollow end  104 . The lamp socket bracket  140  is located and attached within the sheet metal tube  100  and approximately centered within the second round hollow end  104 . A first balancing suspender  110  and second balancing suspender  120  fixedly attach on the top side of the hollow sheet metal tube  100  providing structure to hang the device above the plants. A second suspender hole  125  is cut through the second suspender  120  and the sheet metal tube  100  providing an opening to the lamp socket bracket  140  for electrical connection. 
         [0037]    The reflector  130  is shown in this embodiment being approximately centered in the hollow sheet metal tube  100 . The reflector  130  is bounded by a first reflector end  132  and a second reflector end  134 . The reflector  130  is open towards the plants on the bottom and sealed by a transparent portion  108 . The transparent portion  108  may be constructed from any transparent material that will not melt or distort when exposed to high temperatures while allowing light to pass through to the plants. In the preferred embodiment, the transparent portion  108  is flat, and constructed of tempered glass. The reflector  130  has reflector side channels  310  bent and shaped from the long edges of the reflector  130 . The reflector side channels  310  are of size and dimension matching the transparent portion  108 . The second reflector end  134  has an end channel  300  bent and shaped from its bottom edge and matching the shape and dimensions of the short end of the transparent portion  108 . The transparent portion  108  slides within the reflector side channels  310  fittingly inserting into the end channel  300 , and held in place by the retention flap  170 . In other embodiments, the transparent portion may be held by tabs, sheet metal channels, heat resistant adhesives, or other methods of affixing the transparent portion  108  between the grow lamp and the plants. 
         [0038]    Cooling atmosphere  112  can be flowed into the first round hollow end  102  and exhausted out of the second round hollow end  104 ; or, oppositely, cooling atmosphere  112  can be flowed into the second round hollow end  104  and exhausted out the first round hollow end  102 . Round conduit is not shown, but could be connected making a closed loop cooling system isolating the growing environment from the heated atmosphere impacted by the grow lamp. The cooling atmosphere  112  may consist of air that is introduced at a lower temperature than the grow lamp, or any other gas that will conduct heat while passing around the grow lamp. 
       Description FIG. 2: 
       [0039]      FIG. 2  illustrates a front view of the device demonstrating the lamp socket  210  as seen through the first round hollow end  102 . The lamp socket  210  is fixedly attached to the lamp socket bracket  140  and approximately centered within the hollow sheet metal tube  100 . The second balancing suspender  120  and lamp socket bracket  140  may be connected in by screws, pop rivets, or any other connection method providing a pass through connection to the second balancing suspender  120 , through the hollow sheet metal tube  100 , and into the lamp socket bracket  140 . 
         [0040]    The reflector  130  has a series of reflector bends  200  positioned and angled to reflect light towards the plants while forming a shape that can fit within the hollow sheet metal tube  100 . The second reflector end  134  bounds the reflector  130  and securely attaches to one end of the transparent portion  108 . 
       Description FIG. 3: 
       [0041]      FIG. 3  is a left side view of one embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . The hollow sheet metal tube  100  is constructed from a single sheet of metal having a first round hollow end  102  and a second round hollow end  104 . The hollow sheet metal tube  100  is of a length adequate to house a commercially available grow lamp and accommodate the reflector  130  and first and second reflector ends  132 ,  134 . The cooling atmosphere  112  may flow into the first round hollow end  102  and exhaust out of the second round hollow end  104 ; or, oppositely, the cooling atmosphere may flow into the second round hollow end  104  and exhaust out of the first round hollow end  102 . 
         [0042]    In the embodiment shown in  FIG. 3 , the first and second reflector ends  132 ,  134  bound the reflector  130  at approximately 45-degree angles. The reflector  130  is constructed and arranged to protrude from the hollow sheet metal tube  100 , bisecting the hollow sheet metal tube  100  approximately in half, leaving enough of the hollow sheet metal tube  100  intact at the first and second round hollow ends  102 ,  104  for connection to round conduit. 
         [0043]    The size, shape, angle, and materials used in construction of the reflector  130  and first and second reflector ends  132 ,  134  are determined by the desired photometric characteristics, light intensity, and grow lamp characteristics. The distance from the plants and the number of fixtures being utilized also drive the size, shape and angle of the reflector  130  and first and second reflector ends  132 ,  134 . 
         [0044]    A first balancing suspender  110  and second balancing suspender  120  fixedly attach on the top side of the sheet metal tube  100  providing structure to hang the device above the plants. The location of the first and second balancing suspenders  110 ,  120  is determined by the weight and balance of the device. 
         [0045]    The retention flap  170  pivotally connects to the reflector  130  on the opposite edge as the channel formed by the second reflector end  134 . 
         [0046]    Cooling atmosphere  112  travels in a straight channel flow through the hollow sheet metal tube  100 , and may be flowed into the first round hollow end  102  and exhausted out of the second round hollow end  104 ; or, oppositely, cooling atmosphere  112  can be flowed into the second round hollow end  104  and exhausted out the first round hollow end  102 . 
       Description FIG. 4: 
       [0047]      FIG. 4  illustrates a top side view of one embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . The hollow sheet metal tube  100  is approximately centered with respect to the reflector  130 . The first and second balancing suspenders  110 ,  120  are approximately centered on the hollow sheet metal tube  100  and distanced in from the first and second round hollow ends  102 ,  104  to facilitate connection to round conduit. 
         [0048]    The second suspender hole  125  is located approximately above the previously shown lamp socket bracket  140  allowing access for an electrical service connection to the grow lamp. 
         [0049]    In the preferred embodiment as shown, the transparent portion  108  is securely attached on the short ends via an end channel  300  formed by the second reflector end  134  and reflector side channels  310  and secured in place by the retention flap  170  on the opposite end of the end channel  300 . The retention flap  170  is pivotally connected to the reflector  130 . The reflector side channels  310  are bent, shaped, and formed from the same sheet as the reflector  130  and matched to the size and shape of the transparent portion  108 . When installing the transparent portion  108 , the transparent portion  108  is simply slid into the reflector side channels  310  formed by the reflector  130  until one short end fittingly inserts into the end channel  300  formed by the second reflector end  134 , and securely held in place by the retention flap  170 . The retention flap  170  pivotally connects to the reflector  130  allowing for easy removal of the transparent portion  108  for cleaning. 
         [0050]    The method of securing a piece of flat glass is well known in the art and the inventive device is not limited by the method shown in the preferred embodiment. 
       Description FIG. 5: 
       [0051]      FIG. 5  illustrates a bottom side view of one embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . The hollow sheet metal tube  100  is approximately centered with respect to the reflector  130 . The reflector  130  is shaped and bent to reflect light towards the plants from the grow lamp while being fitted inside the hollow sheet metal tube  100 . The first reflector end  132  is shaped to match the reflector  130  and has an opening approximately matching the first round hollow end  102 . The retention flap  170  is pivotally connected to the reflector  130  and secures the transparent portion  108  by holding said transparent portion  108  in the reflector side channels  310  formed along the long edges of the reflector  130  and an end channel  300  formed along the edge of the second reflector end  134 . The second reflector end  134  is shaped to match the reflector  130  and has an opening approximately matching the second round hollow end  104 . 
         [0052]    The lamp socket bracket  140  is centered within the second round hollow end  104  and positioned to locate the grow lamp under the reflector bends  200 . The grow lamp may be located anywhere within the hollow sheet metal tube  100 , but the preferred embodiment locates the grow lamp between the reflector bends  200  and the transparent portion  108 . 
       Description FIG. 6: 
       [0053]      FIG. 6  illustrates a right side exploded view of the preferred embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . The hollow sheet metal tube  100  has a cut-away portion  600  matching the shape and angle of the reflector  130 . The reflector  130  and hollow sheet metal tube  100  attach at the reflector-to-tube connections  640 . The first reflector end  132  and reflector  130  attach at the first reflector connection  610 . The second reflector end  134  and reflector  130  attach at the second reflector connection  610 . The bracket back plate  680  and lamp socket bracket  140  attach at bracket connection points  690 . The lamp socket bracket  140 , hollow sheet metal tube  100 , and second balancing suspender  120 , attach at the bracket-tube-suspender connection points  670 . Attachment may be made via a bent over tab inserted into a punched out slot, a screw, heat resistant adhesive, or any other method allowing connection between the two pieces of sheet metal. 
         [0054]    The retention flap  170  pivotally connects to the reflector  130  and is of size and shape matching the transparent portion  108 . If a thicker transparent portion  108  is desired, the reflector side channels  310 , end channel  300 , and the retention flap  170  would be constructed having a size and shape matching the thicker transparent portion  108 . 
       Description FIG. 7: 
       [0055]      FIG. 7  illustrates a perspective exploded view of the preferred embodiment of the Forced Air Cooled Metallic Tubular Horticulture Light Fixture as shown in  FIG. 1 . The hollow sheet metal tube  100  has a cut-away portion  600  matching the shape and angle of the reflector  130 . In the embodiment shown the seam  710  is located along the bottom side of the hollow sheet metal tube  100 . The bracket back plate  680  and lamp socket bracket  140  are not connected together until after the wiring is passed through the second suspender hole  125  and connected to the lamp socket  210 . 
         [0056]    The retention flap  170  pivotally connects to the reflector  130  and is of size and shape matching the transparent portion  108 . The reflector side channels  310 , end channel  300 , and the retention flap  170  are constructed and arranged to match the size and dimension of the desired transparent portion  108   
         [0057]    The hollow sheet metal tube  100  is approximately centered with respect to the reflector  130 . The reflector  130  is shaped and bent to reflect light towards the plants from the grow lamp while being fitted inside the hollow sheet metal tube  100 . The reflector bends  200  may be of any number, angle, and shape to match the desired photometric performance, distance of hanging from the plants, or the particular type of grow lamp to be installed. The first and second balancing suspenders  110  and  120  are attached along the top of the hollow sheet metal tube  100  and located to balance the device when hung. 
         [0058]    The first reflector end  132  is shaped to match the reflector  130  and has an opening approximately matching the first round hollow end  102 . The retention flap  170  is pivotally connected to the reflector  130  and secures the transparent portion  108  by holding said transparent portion in the reflector side channels  310  formed along the long edges of the reflector  130  and an end channel  300  formed along the edge of the second reflector end  134 . The second reflector end  134  is shaped to match the reflector  130  and has an opening approximately matching the second round hollow end  104 . 
         [0059]    The lamp socket bracket  140  is centered within the second round hollow end  104  and positioned to locate the grow lamp  601  under the reflector bends  200 . The grow lamp  601  may be located anywhere within the hollow sheet metal tube  100 , but the preferred embodiment locates the grow lamp  601  between the reflector bends  200  and the transparent portion  108 . 
       Description FIG. 8: 
       [0060]      FIG. 8  illustrates a perspective, side, top and end view of the hollow sheet metal tube  100  as shown in  FIG. 1 . The sheet metal tube  100  is formed from a single sheet of metal having a first round hollow end  102  and a second hollow end  104 . The electrical power inlet  700  can be located anywhere, but for the preferred embodiment the electrical power inlet  700  is located on the top side where the inventor anticipates electrical service. The cut-away portion  600  can be of any size, shape, and location along the hollow sheet metal tube  100  so long as the cut-away portion  600  matches the size and shape of the reflector  130 , and enough of the hollow sheet metal tube  100  extends beyond the cut-away portion  600  to allow for slide over connection to round conduit. The sheet metal seam  710  is located along the bottom of the hollow sheet metal tube  100  in the preferred embodiment, but may be located anywhere convenient to manufacturing. 
       Description FIG. 9: 
       [0061]      FIG. 9  illustrates a perspective, side, and end view of the reflector  130 , first reflector end  132 , second reflector end  134 , and the retention flap  170  as assembled and shown in previous  FIGS. 1-8 . 
         [0062]    The reflector side channels  310  are formed from the bottom long edges of the reflector  130 , sized to match the thickness of the desired transparent portion  108 . The end channel  300  is formed from the bottom edge of the second reflector end  134 , sized to match the thickness of the transparent portion  108  shown in earlier Figures. The reflector bends  200  produce the desired photometric performance of the reflector  130 , and can be either many or one. The retention flap  170  pivotally connects to the reflector  130  and is of size and shape matching the transparent portion  108 . 
       Description FIG. 10: 
       [0063]      FIG. 10  illustrates a rear view of the preferred embodiment depicting the lamp socket bracket  140  as seen through the second round hollow end  104 . The lamp socket bracket is approximately centered within the hollow sheet metal tube  100 . The lamp socket bracket  140  may be connected to the hollow sheet metal tube via screws, pop rivets, or some other attachment method that pass through the second balancing suspender  120 , through the hollow sheet metal tube  100 , through the reflector  130 , and attaching to the lamp socket bracket  140 . 
         [0064]    The second reflector end  134  is shaped to match the reflector  130  and has an opening approximately matching the second round hollow end  104 . The transparent portion  108  is held in place by the reflector side channels  310  formed along the long edges of the reflector  130  and an end channel  300  formed along the bottom edge of the second reflector end  134 .