Patent Publication Number: US-2006012978-A1

Title: Offset solar-powered outdoor lighting apparatus

Description:
PRIORITY CLAIM  
      We hereby claim the benefit of U.S. Provisional Patent Application No. 60/571,576 filed May 14, 2004. 
    
    
     FIELD OF THE INVENTION  
      This invention relates generally to outdoor lighting apparatus, and, more specifically, to solar powered outdoor lighting apparatus.  
     BACKGROUND OF THE INVENTION  
      Outdoor lighting can provide an important accent to any yard or garden. A gardener or landscaper may strategically place many lights in a landscape to illuminate walkways and to otherwise enhance the appearance of the landscape at night. Some lighting systems are designed to simply provide light while in others the lights themselves serve ornamental purposes even when they are not illuminated.  
      In many prior systems, lights are wired directly to an adjacent residence through underground power cables. However, underground cables require excessive labor to install and interfere with gardening and landscaping efforts, as they are dug up by tilling, planting, and the like. Other systems have used solar cells to collect electricity in batteries during daylight hours and then use the stored energy to power the lights at night. However, prior systems interfere with the purpose of the lighting system, which is principally aesthetic. The solar cells are prominently mounted to the top or sides of the lighting element and are therefore visible during daylight hours. As time passes, mineral deposits and fading often discolor the solar cell. Ultimately, the solar cell distracts from any ornamental qualities the lighting system was designed to have.  
      In view of the foregoing it would be an advancement in the art to provide a solar powered outdoor lighting system that may be prominently mounted without interfering with ornamental aspects of the lighting system and the surrounding landscape.  
     SUMMARY OF THE INVENTION  
      The present invention comprises a system for providing outdoor lighting including a support, a lighting element assembly, and a collector unit. The support is typically a vertical rod having the lower end thereof inserted in a soil substrate. The lighting element assembly is typically ornamental and contains a lighting element, such as an LED. The lighting element assembly secures to the support near the upper end thereof. The collector unit secures to the support offset a substantial distance from the lighting element assembly. In one embodiment, the distance between the lighting element assembly and collector unit is greater than or equal to approximately 40% of the length of the support.  
      The collector unit contains a solar cell and a battery. In typical applications the collector unit is positioned flush with or below foliage growing from the substrate supporting the lighting system. A light sensitive switch connects the lighting element to the battery and is operable to turn the lighting element on in low light conditions. The light sensitive switch typically mounts to the collector unit near the solar cell. The collector unit may adjustably secure to the support such that its position and orientation relative to the support may be changed in order to store the lighting system or to improve solar power collection.  
      The lighting element assembly has a diffuser positioned over the lighting element to diffuse the light therefrom. In one embodiment, the diffuser is made of cracked glass to enhance visibility thereof. A support adapter secures the diffuser and lighting element to the support and has a diffuser receptacle, a lighting element seat, and a support receiver sleeve. The diffuser receptacle receives a portion of the diffuser to secure the diffuser to the support. In some embodiments, a threaded attachment secured to the diffuser directly engages a threaded region on the receptacle. Apertures may be formed in the diffuser receptacle to enable drainage of moisture built up within the diffuser.  
      The lighting element is positioned within the lighting element seat, which is located within the diffuser receptacle. The lighting element seat opens into the support receiver sleeve and provides a channel receiving a wire that extends from the collector unit to the lighting element. The support receiver sleeve receives the end of the support to secure the support adapter thereto. In some embodiments, a lighting element shield may be positioned over the lighting element and lighting element seat to protect the lighting element from moisture.  
      As will be readily appreciated from the foregoing summary, the invention provides a robust, weather resistant outdoor lighting system having an ornamental lighting element assembly that may be prominently placed whereas the solar cell and battery providing power thereto are contained within a discreetly positioned collector unit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.  
       FIG. 1  is a perspective view of a lighting system, in accordance with the present invention;  
       FIG. 2  is a perspective view of an alternative embodiment of a lighting system, in accordance with the present invention;  
       FIG. 3  is a side view of a collector unit, in accordance with the present invention;  
       FIG. 4  is an upper quarter perspective view of a collector unit, in accordance with the present invention;  
       FIG. 5  is a lower quarter perspective view of a collector unit, in accordance with the present invention;  
       FIG. 6  is a cutaway perspective view of a lighting element assembly, in accordance with the present invention;  
       FIG. 7  is an exploded view of a LED mounting system, in accordance with the present invention;  
       FIG. 8  is a side view of a lighting system having a support adapted for placement on a flat surface;  
       FIG. 9  is a front view of a lighting system having a support adapted to suspend the lighting element assembly from a support structure; and  
       FIG. 10  is a front view of a lighting system having multiple suspending lighting element assemblies. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to  FIG. 1 , a lighting system  10  may include a lighting element assembly  12 , a support  14 , and a collector unit  16 . The lighting element assembly  12  typically includes a light producing means such as an incandescent lamp or LED. The lighting element assembly  12  secures near the upper end of the support  12  a distance  18  from the collector unit  16 . In typical uses, the collector unit  16  will be positioned at or below the upper boundary of foliage and the like in order to minimize its visual impact. The collector unit  16  typically contains a solar cell and a battery, or like means, for collecting and storing solar energy during daylight hours. The solar cell and battery may be integrated in the collector unit  16  or may secure separately to the support  14 . Wiring (not shown) connects the lighting element assembly  12  to the collector unit  16 .  
      The support  14  may be straight, curved, or sloped, or have a non-deterministic ornamental shape. In the illustrated embodiment the support  14  is embodied as a straight rod  20 . The rod  20  may be hollow or solid and may have any cross section offering sufficient strength to support the lighting element assembly  12 . It may be one monolithic rod or assembled from smaller sections. The sections may be telescoping with fasteners maintaining the sections in place. Alternatively, the sections may thread into one another or secure to one another by threaded connecting pieces. In the illustrated embodiment, the rod  20  is made of stainless steel due to its resistance to weathering; however aluminum and rigid, weather-resistant plastics such as polycarbonate, polypropylene, or polyvinylcholoride, may also be used.  
      The lower end of the rod  20  typically inserts into the soil or other substrate and may have a sharpened tip to facilitate insertion. The sharpened tip is either integrally formed with the rod  20  or secured by threads, press-fit, weld, or like attachment means. In other embodiments, the lower end of the rod  20  may be supported by a broad-based stand or other structure that simply rests on the substrate. Such a support mechanism may be used when, for example, the lighting system  10  is placed on a wooden deck or cement patio where insertion is not practicable.  
      To preserve the aesthetic aspects of the lighting system  10  it may be advantageous to position the collector unit  16  away from the prominent lighting element assembly  12 . In the illustrated embodiment, in which the support  14  is embodied as a substantially straight rod  20 , the collector unit  16  may secure to the rod  20  such that the distance  18  between itself and the lighting element assembly  12  is equal to about 40 percent or more of the length of the rod  20 .  
      In other embodiments, the support  14  may extend horizontally. Accordingly, the collector unit  16  may be separated a horizontal distance from the lighting element assembly  12  as well as a vertical distance. For example, the support  14  may be embodied as two stakes, one having the lighting element assembly  12  secured thereto and the other having the collector unit  14  secured thereto. Accordingly, the lighting element assembly  12  may be placed prominently whereas the collector unit  16  is placed more discreetly. In addition, the position of the lighting element assembly  12  may be chosen with reference to aesthetics, whereas the position of the collector unit  12  may be chosen based on light conditions.  
      Referring to  FIG. 2 , in some embodiments, other ornamental features secure to the support  14 . For example, in the embodiment of  FIG. 2 , wires  22  for facilitating growth of climbing plants secure along the length of the rod  20  in a helical shape. Other features such as hooks for hanging plants, decorative wrought iron, or the like may likewise secure to the rod  20 .  
      Referring to  FIG. 3 , the collector unit  16  may be adaptable to varying foliage and lighting conditions. For example, in the illustrated embodiment, the location of the collector unit  16  may be adjusted in vertical direction  30 . Thus, in high thick foliage, the collector unit  16  may secure higher on the support  14  to increase the amount of sunlight incident thereon. The collector unit  16  may also be rotable in direction  32  to facilitate both storage and solar power collection. For example, the representation in solid lines is positioned suitable for shipping and storage or for situations where most of the incident light will be horizontally directed. The dotted representation illustrates a deployed position for areas wherein incident light comes generally from above the collector unit  16 . The collector unit  16  may also be rotatable in direction  34  about the support  14  to further facilitate proper orientation of the collection unit  16 .  
      Referring to  FIG. 4 , the collector unit  16  typically contains a solar cell  40  secured to a housing  42 . Batteries may be enclosed by the housing  42  or secure to the support  14  at a different location. A light sensor  44 , typically positioned on the same face of the housing  42  as the solar cell  40 , serves to automatically close an electrical circuit between the battery and lighting element assembly  12  at low light intensities. In other embodiments, the light sensor  44  is separate from the collector unit  16  and secures separately to the support  14  such as near the lighting element assembly  12  or a substantial distance therefrom. Where the lighting element assembly  12  is separated from the light sensor  44 , the light sensor  44 ′ may be less likely to detect light from the lighting element assembly  12  and misinterpret lighting conditions. However, the light from the lighting element assembly  12  may be of insufficient intensity to cause such misinterpretations.  
      Referring to  FIG. 5 , a wire  50  typically extends from the collector unit  16  to the lighting element assembly  12 . In embodiments of the invention having a support  14  embodied as a hollow rod  20 , the wire  50  may be directed through an aperture  52  in the rod  20  and pass through the rod  20  to the lighting element assembly  12 . Alternatively, the wire  50  may wrap around the exterior of the support  14 . In embodiments having a telescoping rod  20 , coiling the wire  50  around the rod  20  enables adjustment in length without interference from the wire  50 .  
      Bays  54  may be formed in the housing  42  to receive batteries for storing electrical energy generated by the solar cell  40  during daylight hours for use in the evening and at night. Alternatively, batteries may be stored in the lighting element assembly  12 . In such an embodiment, the wire  50  would connect to the solar cell  40  and carry electrical power to the batteries. In some embodiments, a circuit board resides within the housing  42  and regulates voltage passing to and from the batteries and to the lighting element assembly  12 . The circuit board may also receive the output of the light sensor  44  and turn on the lighting element assembly  12  when the output indicates low light levels and turn it off when the output indicates high light levels.  
      The versatility in positioning and orienting the collector unit  16  may be facilitated by a clamp  56  having a ‘U’ shape. The arms  58  of the U receive fasteners  60 , such as screws, bolts, or the like, which are selectively tightened to secure the clamp  56  to the rod  20 . A flange  62  formed in the housing  42  may be positioned between the arms  56  to be clamped thereby. In some embodiments, one of the fasteners  60  also extends through the flange  62 , establishing a point of rotation when adjusting the orientation of the collector unit  16 . In operation, the fasteners  60  are loosened to permit alteration in the position and orientation of the collector unit  16  and then tightened to prevent further movement. The clamp  54  typically secures to the rod  20  near the aperture  52 . In some applications, the clamp  54  secures over the aperture  52  to hinder the entry of contaminants and to make it less visible.  
      In some embodiments, an on/off switch  64  may secure to the housing  42 . The on/off switch  64  is interposed between the batteries and the lighting element assembly  12 , enabling a user to optionally turn off the lighting element assembly regardless of the output of the light sensor  44 .  
      Referring to  FIG. 6 , a lighting element assembly  12  may include a diffuser  70 , a support adapter  72 , and a lighting element  74 . The diffuser  70  typically serves to scatter light from the lighting element  74 . It may be embodied as a globe, or other three-dimensional shape positionable over the lighting element  74 . One or both of the interior and exterior surfaces may be colored, textured, or treated to enhance the diffusing properties of the diffuser  70 . In the illustrated embodiment, the diffuser  70  is formed of cracked glass. Cracked glass provides the advantage of concentrating light from the lighting element  74  at many fine cracks formed in the glass, creating a stunning visual effect while maximizing visibility. A lighting element  74  embodied as an LED may have relatively low light output and therefore may benefit from means to increase the visibility of the light therefrom. Where the interior or exterior surfaces are simply frosted, or the like, the light from the lighting element  74  is diffused over a much greater area than cracked glass, resulting in lower visibility.  
      The support adapter  72  typically includes a diffuser receptacle  76 , a support receiver sleeve  78 , and a lighting element seat  80 . The diffuser receptacle  76  mates with a portion of the diffuser  70  or an attachment  82  secured to the diffuser  70 . The diffuser  70  or attachment  82  may fit around the receptacle  76 , within the receptacle  76 , or rest on a seat formed in the receptacle  76 . In the illustrated embodiment, the receptacle  76  is an annular pocket formed by an outer wall  84  circumscribing the lighting element seat  80 . The receptacle  76  mates with a tubular attachment  82 , or a tubular structure monolithically formed with the diffuser  70 , having threads  86  matable with corresponding threads  88  formed on the interior surface of the outer wall  84 . The threads  88  may circumscribe the entire wall  84  or be partial threads sufficient to retain the threads  86 . Alternatively, the attachment  82  may secure to the receptacle  76  by means of a press-fit or adhesive.  
      Threaded securement of the diffuser  70  to the diffuser receptacle  76  by means of the attachment  82 , or like structure, may enable a user to readily customize the appearance of the lighting system  10 . For example, a diffuser  70  matching the flowers currently in season or having a theme matching an upcoming holiday may be readily substituted into the receptacle  76 .  
      Rain, condensation within the diffuser  70 , and the like may result in water within the diffuser  70  that may result in discoloration, stains, mineral deposits, or damage to the lighting element  74 . Accordingly, apertures  90  may be formed in the receptacle  76 , typically in the lower portion thereof. In the illustrated embodiment, the apertures  90  are formed in the lower portion of the outer wall  84 . The apertures  88  of  FIG. 6  also enable insertion of shims during the manufacturing process to facilitate formation of the threads  88 .  
      The attachment  82  secures to the diffuser  70  by means of adhesive, press-fit, threads, or the like. In the illustrated embodiment, a seat  92  formed near the top of the attachment  82  fits within an opening formed in the diffuser  70 . Adhesive placed on the seat  92  secures the diffuser  70  thereto.  
      The support receiver sleeve  78  typically receives a portion of the upper end of the support  14 . In the illustrated embodiment, the rod  20  inserts within the sleeve  78 , though in some embodiments the sleeve  78  fits within the rod  20 . The rod  20  is secured to the sleeve  78  by adhesive, press-fit, or other like fastening means. The sleeve  78  typically extends through the support adapter  72  to the lighting element seat to provide a channel for receiving the wire  50 .  
      Referring to  FIG. 7 , while still referring to  FIG. 6 , in the illustrated embodiment, the lighting element seat  80  receives a lighting element  74  embodied as an LED circuit board  100  having an LED mounted thereon. The LED may be amber, or any other color output by LED&#39;s. In some embodiments, phosphorescent coating over the LED results in light having wavelengths other than those outpout by the LED. The circuit board  100  typically has leads  102  extending therefrom. The leads  102  extend through apertures  104  formed in an LED mount plate  106 . The mount plate  106  secures within the lighting element seat  80  by means of adhesive or a like securement means. In typical applications, the wire  50  will be connected to the leads  102  prior to securing the mount plate  106  to the lighting element seat  80 . The lighting element seat  80  typically opens into the support receiver sleeve  78 , providing a channel through the support adapter  72  to receive the wire  50 . A lighting element shield  108  (as shown in  FIG. 6 ), such as a transparent dome, may then be placed over the lighting element  74  to protect against weathering. In the illustrated embodiment, the shield  108  fits around the lighting element  74  and lighting element seat  80  and is secured by either adhesive or press-fit. In some embodiments, the shield  108  extends downwardly to near the point of attachment of the outer wall  84  to the support adapter  72  to provide additional protection.  
      Referring to  FIG. 8 , in some embodiments the support  14  may be embodied as a stand  120  or base  120  supporting the lighting element assembly  12  or integrally formed with the lighting element assembly  12 . In such embodiments, the collector unit  16  may secure to a structure other than the support  14  such as a table  122  supporting the base  120 . The wiring  50  is typically of sufficient length to extend from the collector unit  16  to the lighting element assembly  12 . The collector unit may be positioned discretely on the table  122  or other support structure. For example, the collector unit may secure to the underside of the table  122  by means of VELCRO or to the legs of the table  122  by straps, or the like.  
      Referring to  FIGS. 9 and 10 , in other embodiments, the support  14  is embodied as hooks  130  suspending the lighting element assembly  12  from a support structure  132  such as a tree branch or the eave of a house. The collector unit  16  may likewise secure to the support structure by means of a hook  134  or like fastener. In typical applications, the collector unit  16  will be positioned away from the lighting element assembly  12 . Multiple lighting element assemblies  12  each suspended from a hook  130  may be coupled by wiring  50  to a single collector unit  16 , as illustrated in  FIG. 10 . The diffuser  70  in such embodiments may be a paper lantern common in some Asian and Latin American cultures.  
      While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.