Patent Publication Number: US-8123381-B1

Title: LED lighting systems and methods useable for replacement of underwater niche lights and other applications

Description:
RELATED APPLICATIONS 
     This patent application claims priority to U.S. Provisional Patent Application Nos. 60/970,847 filed Sep. 7, 2007 and 60/979,291 filed Oct. 11, 2007, the entire disclosures of which are expressly incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to light emitting diode (LED) lamps useable in underwater lighting applications for swimming pools and the like and to the replacement of existing incandescent light bulbs with LED light sources in underwater lighting applications for swimming pools and the like. 
     BACKGROUND OF THE INVENTION 
     Swimming pools and spas often have lights which are located below the water level to illuminate water within the pool or spa. This is typically accomplished by mounting a light bulb within a fixture that is located in a water-tight cavity known as a “niche” formed in the wall of the pool or spa. The watertight cavity or niche typically has an outer lens that prevents water from entering the fixture or niche. 
     In many existing swimming pools and spas, incandescent light bulbs are mounted within the niches. In recent years it has become known to replace those existing incandescent light bulbs with LED light sources in order to conserve power, provide varied colors of light and/or obtain greater light intensity. 
     For example, U.S. Pat. No. 6,184,628 (Ruthenberg) describes the use of predetermined arrays of a plurality of different colored LED bulbs to replace an incandescent pool light where the plurality of different colored LED bulbs are wired in such a manner that the predetermined arrays of plurality of different colored LED bulbs activate at predetermined sequences for predetermined time intervals wherein the bulbs are encased in a lens. Even though LED bulbs are used, providing LED lighting fixtures with brightness to rival incandescent bulbs is still an issue, especially when not all of the LED bulbs are illuminated, as suggested in the &#39;628 patent. 
     United States Patent Application Publication Nos. 20030048632 (Archer) entitled “Light Emitting Diode Pool Assembly” and 2004/0223320 (Archer et al.) entitled “Nicheless Pool Light System” describe an LED light assembly that has a reflective plate with a plurality of perforations formed through the reflective plate. LED bulbs protrude through the perforations in the reflective plate. A control circuit is selectively operable to produce light in a plurality of colors through the LED bulbs. The control circuit comprises a switch that, when activated a defined number of times, produces a plurality of at least light colors and light patterns, wherein each of the plurality of at least light colors and light patterns are selected based on the defined number of times the switch is activated. 
     United States Patent Application Publication No. 20070159833 (Netzel et al.) entitled “LED Pool and Spa Light” describes a lighting fixture that includes a heat sink having a first mounting portion attached to a housing. A first circuit board containing LEDs is mounted to a first side of a second mounting portion of the heat sink. A second circuit board include an LED control circuit is mounted to a second side of the second mounting portion. A multi-layer circuit board includes a heat-dissipating core bonded to first and second dielectric substrates, which are bonded to first and second electrically conductive layers. An electrical conductor extends through a through-hole in the board to electrically connect the first and second conductive layers. An electrical insulator inside the through-hole electrically isolates the core from the conductor. A transparent cover is shaped to cause downwardly projecting light rays emitted from the LEDs to be refracted more than upwardly projecting light rays. The cover also includes vertically extending projections for horizontally refracting light. 
     United States Patent Application Publication No. 20060187652 (Doyle) entitled “LED Pool or Spa Light Having Unitary Lens Body” describes a light emitting diode pool or spa lamp bulb having at least one light emitting diode with at least one lens body that is optically clear. The light emitting diode(s) is/are embedded in the lens body and the lens body is in direct contact with the water within the pool or spa. 
     However, the use of LED light sources to replace incandescent lights in swimming pool and spa underwater fixtures and niches has been subject to certain limitations and difficulties. For example, because LED&#39;s produce substantial amounts of heat, the power of the LED&#39;s used in the replacement light source has, in at least some applications, been limited by the tendency for heat to collect within the water-tight fixture or niche. Also, in at least some applications, when a plurality of LED&#39;s cast light though an existing lens positioned over the water-tight fixture or niche, a plurality of light columns or spots are projected through the water instead of a desired diffuse distribution of light through the pool water. Thus, there remains a need in the art for the development of new LED lighting systems which may be used to replace existing incandescent or LED light sources in swimming pool and spa light fixtures and niches. 
     SUMMARY OF THE INVENTION 
     The present invention provides improved LED lighting systems and methods which may be used in a variety of applications, such as replacement of existing LED light sources or incandescent light bulbs within lighting fixtures or niches of the type used in swimming pool, spa, fountain and other underwater applications. 
     In accordance with the present invention, there is provided an LED lighting system that is useable to replace an existing LED or non-LED light source in a niche (such as an underwater niche) that has an existing lens through which light passes, but wherein the existing lens will cause an undesired optical effect (e.g., causing the light to project in discrete columns or spots) on light that passes through that lens from the replacement LED light source. This LED lighting system generally comprises (A) at least one LED, (B) a circuit board connected to the LED(s) for driving the LED(s) and (C) a corrective apparatus, such as a corrective lens (e.g., a diffuser or holographic diffuser), constructed to prevent, counteract or correct the undesired optical effect of the existing niche lens. 
     Further in accordance with the invention, there is provided an LED lighting system that comprises (A) a housing; (B) at least one LED; (C) at least one circuit board connected to the LED for driving the LED; and (D) an air moving device (e.g., a fan) for cooling the LED(s) and/or the circuit board(s). One or more flow-through openings (e.g., holes or open vias) may be formed in the circuit board such that the air moving device may cause air to flow therethrough. Also, one or more inflow opening(s) and one or more outflow opening(s) may be formed in the housing (or on a lens affixed to the front of the housing) so that the air moving device can draw air into, and exhaust air out of, the interior of the housing. 
     Still further in accordance with the invention, there is provided an LED lighting system that that is useable to replace an existing LED or non-LED light source in a niche (e.g., an underwater niche) that has an existing niche lens that is constructed such that it will cause an undesired optical effect (e.g., causing the light to project in discrete columns or spots) on light that passes through that existing niche lens from the replacement LED light source (e.g., causing the light to project in discrete columns or spots). This LED lighting system generally comprises (A) a housing; (B) at least one LED; (C) at least one circuit board connected to the LED for driving the LED; (D) an air moving device (e.g., a fan) for cooling the LED(s) and/or the circuit board(s) and (E) a corrective apparatus, such as a corrective lens (e.g., a diffuser or holographic diffuser), constructed to prevent, counteract or correct the undesired optical effect of the existing niche lens. 
     Still further in accordance with the present invention, there are provided methods for using the LED lighting systems of the foregoing character to replace existing LED light sources or existing incandescent light bulbs in niches (e.g., underwater niches), such as those used in swimming pool, spa, fountain and other underwater applications. 
     Further aspects, elements, objects, details and examples of the devices and methods of the present inventions will be understood by those of skill in the art upon reading of the detailed description and examples set forth herebelow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of one embodiment of an LED lamp of the present invention. 
         FIG. 2  is an exploded perspective view of the LED lamp of  FIG. 1 . 
         FIG. 3  is a front perspective view of the LED lamp of  FIG. 1  wherein components on the front surface of the lamp&#39;s circuit board are visible through the transparent front lens of the lamp. 
         FIG. 4  is a schematic diagram showing an LED lamp of the present invention mounted within a swimming pool light niche. 
         FIG. 5  is one example of a driver circuit diagram for a white LED system of  FIG. 1 . 
         FIG. 6  is one example of a driver circuit diagram for an RGB LED system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION AND EXAMPLES 
     The following detailed description and the accompanying drawings to which it refers are intended to describe some, but not necessarily all, examples or embodiments of the invention. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The contents of this detailed description and the accompanying drawings do not limit the scope of the invention in any way. 
       FIGS. 1 through 3  show one example of an LED system  10  of the present invention which may be used, in some applications, to replace an existing LED light source or incandescent light bulb within a niche (e.g., an underwater niche) of the type used in swimming pool, spa, fountain and other underwater applications. This system  10  generally comprises a lens  12  mounted on the front of a concave housing  14 . The lens  12  optionally has a central corrective region  16  surrounded a clear or non-corrective peripheral region  18 . Air inflow openings  20  are formed at spaced apart locations around the periphery of the lens  16 , as shown. Air outflow openings  22  are formed at spaced-apart locations around the housing  14 , as shown. Those of skill in the art will understand that the air inflow openings  20  and air outflow openings  22  could alternatively be formed at locations other than those shown in this example. 
     Within the housing  14 , behind the lens  12 , is an LED driver printed circuit board (PCB)  26  having an LED driver circuit (diagramed in  FIG. 5 ) and a plurality of LED&#39;s  32  mounted thereon. In embodiments where the lens  16  includes the optional corrective region  16 , the LED&#39;s  32  may be positioned behind the optional corrective region  16  of the lens  12  so that light cast from the LEDs will pass through the corrective region  16  of the lens  12 . Flow-through openings  28  are formed in the LED driver printed circuit board (PCB) assembly  26  to allow air to pass through the circuit board  26 . In the particular embodiment shown, each flow-through opening  28  is approximately 0.25 inches in diameter, although other sizes and shapes of openings may alternatively be used. Also, in the particular embodiment shown, the LED&#39;s may comprise either 12, 2.5 W Cree XR-E series white LED&#39;s for a white swimming pool light or 14 red-green-blue (RGB) LEDs (e.g., 6 Red, 4 Green and 4 Blue Cree XR and XR-E series LEDs) for a RGB pool light, along with a low dropout analog LED driver circuit. 
     A fan controller PCB  42  is mounted a spaced distance behind the LED driver printed circuit board (PCB) assembly  26  and a fan  38  is attached to the back side of the fan controller PCB assembly  42 . An open space  44  which functions as a low pressure air plenum exists between the LED driver printed circuit board (PCB) assembly  26  and the fan controller PCB assembly  42 . One or more opening(s), such as a central opening  43  located in front of the fan  38 , may be formed in the fan controller PCB  42  to allow the fan  38  to draw air from the open space  44  which functions as a low pressure air plenum. 
     A transformer  30 , such as a 120 volt AC to 14 volt AC toroidal transformer, is mounted within the housing  14  beneath the fan  38 . The fan  38  and LEDs  32  are connected to and powered by the transformer  30 . 
       FIG. 4  shows the manner in which the LED lighting system  10  of  FIGS. 1-3  may be used to replace an existing LED light source or incandescent bulb within a niche (e.g., an underwater niche). In this example, the niche  50  comprises a concave space  51  formed within a wall (e.g., the side wall of a swimming pool, spa, fountain or other water containing structure). A water tight lens  52  is mounted on the front of the niche  51 . A female light bulb receptacle  54  is positioned within the base of the niche  50 . The niche lens  52  is initially removed and the existing LED light source or bulb is unscrewed and removed from the female light bulb receptacle  54 . The threaded contact base  24  of the LED light system  10  of this invention is screwed into the female light bulb receptacle  54  within the niche  50  and the niche lens  52  is again attached to the front of the niche  50 . When energized, current is received by the transformer  30 , the LEDs  32  are illuminate and the fan  38  begins to run. The running fan  38  pulls air inwardly from the niche&#39;s concave internal space  51 , through inlet openings  20 , through the plurality of flow-though openings  28  in the LED circuit board  26 , through the central opening  43  of the fan driver PCB  42  and outwardly through the air outflow openings  22  and back into the interior space  51  of the niche  50 . In this manner, heat is continually dissipated from the LEDs  32  and is distributed throughout the interior space  51  of the niche  50 . 
     The device may be specifically configured to facilitate a circulating flow or air over the LED(s)  32  to remove heat from the LED(s)  32 . The novel cooling capability of this system  10  allows high power LED(s) to be used without problems due to heat build up. Additionally, LED lighting assemblies of this invention may be used to replace low power LEDs or non-LED light sources (e.g., incandescent light bulbs) in pre-existing fixtures or niches such as swimming pool light niches. 
     In at least some cases, such as where the niche lens  52  was originally designed for use with an incandescent bulb, the passage of light from the individual LED&#39;s  32  through the niche lens  52  may result in undesirable effects on the projected light, such as separation of the light into individual columns resulting in a plurality of individual spots of light rather than casting of diffuse light throughout the water. To remedy this, the lens  12  of the LED lighting system  10  may incorporate the optional corrective region  16  which is optically designed to prevent, counteract or correct the undesired optical effect of the existing niche lens  52 . For example, when the LED lighting system  10  is used to replace an incandescent light bulb in a typical swimming pool niche light, the corrective region  16  of the lens  12  may comprise a polycarbonate holographic light shaping diffuser for homogenized light, available commercially from Luminit, 20600 Gramercy Place, Bldg. 203, Torrance, Calif. 90501-1821. 
       FIG. 5  shows one non-limiting example of a type of LED driver circuit that may be provided on the LED driver PCB  26  in a typical white swimming pool light of the present invention. The specific components of this circuit are described in U.S. Provisional Patent Application Nos. 60/970,847 filed Sep. 7, 2007 and 60/979,291 filed Oct. 11, 2007, the entire disclosures of which are expressly incorporated herein by reference. 
       FIG. 6  shows one non-limiting example of a type of LED driver circuit that may be provided on the LED driver PCB  26  in a typical RGB swimming pool light of the present invention. The specific components of this circuit are described in U.S. Provisional Patent Application Nos. 60/970,847 filed Sep. 7, 2007 and 60/979,291 filed Oct. 11, 2007, the entire disclosures of which are expressly incorporated herein by reference. 
     It is to be appreciated that the invention has been described hereabove with reference to certain examples or embodiments of the invention but that various additions, deletions, alterations and modifications may be made to those examples and embodiments without departing from the intended spirit and scope of the invention. For example, any element or attribute of one embodiment or example may be incorporated into or used with another embodiment or example, unless otherwise specified of if to do so would render the embodiment or example unsuitable for its intended use. Also, where the steps of a method or process have been described or listed in a particular order, the order of such steps may be changed unless otherwise specified or unless doing so would render the method or process unworkable for its intended purpose. All reasonable additions, deletions, modifications and alterations are to be considered equivalents of the described examples and embodiments and are to be included within the scope of the following claims.