Abstract:
An underwater light includes a high intensity lamp placed in an enclosure that allows for easy lamp replacement in case of breakage or natural failure. Electrical wires are soldered to a metal fitting on the lamp. The metal fitting is received in a plastic nipple and the space between the fitting and nipple is filled with a sealant, leaving the ends of the wires exposed. The wires are connected by water proof wire nuts and the end of the lamp is enclosed by a rubber boot and an end cap. When the lamp burns out, it is easily replaced by fishing the light out of the water, removing the rubber boot to expose the wire nuts. The wire nuts are removed and the old lamp discarded. A new lamp is installed in reverse order.

Description:
[0001]     This invention relates to an underwater light, and more particularly to an underwater light which is easy to install and which is easy to replace the bulb.  
       BACKGROUND OF THE INVENTION  
       [0002]     Underwater light sources have been installed for many years in order to illuminate canals in housing developments. These lights attract fish, provide illumination and generally are attractive.  
         [0003]     There are problems with installing and maintaining prior art underwater lights. As a general rule, when the bulb of a prior art underwater light burns out, it is difficult and expensive to replace the bulb because of the construction of the assembly.  
         [0004]     Underwater light assemblies are known in the prior art, such as in U.S. Pat. Nos. 1,745,901; 3,005,908; 3,946,263; 4,598,346 and 6,315,429 and printed application 2002/0178641. Of more general interest are U.S. Pat. Nos. 4,500,151 and 4,869,683.  
       SUMMARY OF THE INVENTION  
       [0005]     This invention addresses the need of an underwater lighting system that is easily installed and inexpensively repaired by the consumer. Other systems advertise the need of the installation and the factory replacement of the lamp by trained individuals. The replacement of the lamp in this system is easily done by anyone familiar with the use of a soldering gun. Unlike other systems using a mogul socket or porcelain lamp holder, made by such manufacturers as Philips, to couple the lamp electrically to the wires, none is needed or used in this system. A simple yet very effective method of coupling the wires to the lamp is done by soldering, eliminating one component prone to failure.  
         [0006]     This underwater lighting system can be easily placed in the water, which is typically a canal and be easily retrieved with minimal effort. Current systems use a non-flexible conduit to enclose and protect the wire. This system uses a highly flexible conduit to protect the wire while enabling the simple procedure of deployment and retrieval.  
         [0007]     This invention addresses the need of an underwater system that allows for the placement of the lamp in various depths of water. It is generally known that lamps placed approximately no deeper than 5 feet below the water surface allow both the desired brightness needed while allowing the lamp to be deep enough to insure sailboat keels and boat props from inadvertently damaging the lamp. The combination of new and different components allow for this result. These physical differences are substantial and significant. Previous references have not shown a combination of these components, resulting in an operational advantage to the user. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is an overall schematic view of the underwater lighting system of this invention;  
         [0009]      FIG. 2  is a side view of a high profile model used when water depth is greater than 7 feet; and  
         [0010]      FIG. 3  is a view similar to  FIG. 2 , showing the lamp in enlarged cross-section compared to the weight assembly. 
     
    
     DETAILED DESCRIPTION  
       [0011]     Referring to  FIGS. 1-3 , the underwater light  10  of this invention comprises a lamp  12  electrically coupled to a transformer  14  by a pair of suitable insulated wires  16 ,  17  being part of an insulated three wire assembly  15  received in and protected by a flexible conduit  18 . Currently the preferred lamp  12  is a mercury vapor lamp, although any high intensity lamp may be used. Mercury vapor lamps have been used successfully by numerous builders of underwater lighting systems since the early to mid 1990&#39;s. The transformer  14  is controlled by a photoelectric eye (not shown) that automatically turns the light on at night and off at daybreak. The transformer  14  is coupled to an electrical source on shore using a ground fault circuit interrupter to meet electrical code requirements.  
         [0012]      FIG. 2  shows a high profile model used when water depth is greater than 7 feet. The flexible conduit  18  is coupled directly to a PVC nipple  20  of a lamp enclosure  22 . Lamps have been successfully placed in water to depths of 20 feet. This system does not use rebar or a ballasted receptacle to anchor the receptacle to the bottom. Instead, an adjustable weight  24 , separate and unattached from the lamp enclosure, is incorporated. This moveable weight can be made from any material not susceptible to disintegration in water. Currently, the preferred substance is concrete.  
         [0013]     The weight  24  is designed using a small length of 1¼″ O.D. PVC pipe  26  running through the concrete. The PVC pipe  26  is only large enough to allow the flexible conduit  18  to enter and exit. The weight  24  is then run down the length of the flexible conduit  18  to a position pre-determined by water depth. The weight  24  is secured in place by stainless steel clamps  28  along a portion of the flexible conduit  7  which preferably are sufficiently large to prevent weight  24  from moving along the conduit  18 . The moveable weight  24  not only allows for different depths of water levels but also allows flexibility for the lamp to move vertically in the water, thus helping to avoid objects that may hit and break the lamp. Rebar and other methods of weighting by previous systems are not needed. If more weight is needed for conditions where stronger currents are found, additional weights can be slid down the length of the conduit  18 .  
         [0014]     When water depths do not exceed 6 to 7 feet, a shallow water version of this invention may be devised simply by placing a rigid 90° ell attached to the nipple  20  at one end and to the flexible conduit  18  at the other end.  
         [0015]      FIG. 3  shows the lamp  12  and the enclosure  22  of this invention. The lamp  12  includes a glass envelope or bulb  30  housing one or more electrically powered light producing elements  32  and a metal fitting  34  typically providing conventional screw threads  36  thereon and a central button  38  insulated from the metal fitting  34 . The lamp  12  is accordingly of conventional design and would normally screw into a conventional porcelain lamp holder, such as a Philips mogul socket. Instead, in this invention, the metal conductors of a pair of insulated wires  40 ,  42  are soldered to the metal threads  36  and button  38  to provide the necessary electrical connection.  
         [0016]     The lamp enclosure  22  comprises an electrically insulating nipple  44  juxtaposed to and preferably abutting the glass envelope  30  and receiving the metal fitting  34 . The nipple  44  is typically made of a polymeric material, such as polyvinyl chloride polymer or other suitable plastic. The space between the lamp  12  and the nipple  44  is filled with a suitable sealant  46 , which is preferably an epoxy sealant such as is available from Minnesota Mining and Manufacturing, Inc. of St. Paul, Minn. under the name SCOTCH-CAST. As shown in  FIG. 3 , the sealant  46  covers the button  38  and the ends of the wires  40 ,  42  thereby electrically isolating the lamp  12  from any water that might accidentally enter the lamp enclosure  22 . Preferably, the sealant  46  extends to both ends of the nipple  44 . Because most wires used inside the flexible conduit  18  include a ground wire  45 , one end of an insulated wire  47  is embedded in the sealant  46  to provide an anchor for the ground wire  45 .  
         [0017]     The wires  40 ,  42  are connected to wires  16 ,  17  by water proof wire nuts  50  which are sufficient to keep water away from the metal conductors in the wires  16 ,  17 ,  40 ,  42 . Suitable water proof wire nuts are commercially available from King Innovation of St. Charles, Mo. under the name DRYCONN. In the alternative, conventional wire nuts can be made water proof by injecting a sealant, such as the sealant  46 , into the open end of the wire nuts  50 . Although a water proof wire nut  51  may be used to connect the ground wire  45  to the wire  47 , the wire nut  51  is preferably not waterproof so the ground fault indicator acting on the wire assembly  15  at the transformer  14  will shut off in the event water seeps into the lamp enclosure  22  and the wire  47  inside the sealant  46  has grounded to metal components of the lamp  12 .  
         [0018]     The lamp enclosure also comprises a rubber boot  52 , which is typically a tapered rubber plumber&#39;s boot of suitable size, usually 2″×3″, clamped to the nipple  44  by one or more suitable clamps  54 , such as stainless steel or other non-corrodible hose clamps. The end of the boot  52  is closed off by an electrically insulated cap  56  made from polyvinyl chloride or other suitable polymer providing an outlet in which the nipple  22  is threaded. The cap  56  includes an end cap  58  having a nipple  60  glued in the open end thereof to provide a sufficient length so the boot  52  may be easily clamped to the cap  56  by one or more clamps  62 , such as stainless steel or other non-corrodible hose clamps. There is an advantage for the boot  52  to be tapered. The small end of the boot  52  allows the nipple  44  to slide inside. The large end of the boot  52  slides over the nipple  60  comprising part of the end cap  56  and provides sufficient room to tie a knot in the cable assembly  15 . A potting compound  64 , such as the same material as the sealant  46 , covers the bottom of the end cap  58  and seals the enclosure  22  against water entry.  
         [0019]     Manufacture and assembly of the underwater light should now be apparent. In a suitable shop, the conductors of the wires  40 ,  42  are soldered to the metal fitting  34  and button  38 . The nipple  44  is placed over the metal fitting  34 , the bulb  12  is inverted and the sealant  46  is poured into the nipple  44  and embedding the end of the wire  47  in the sealant  46 . A bead of caulk  66  is applied between the base of the bulb  12  and the nipple  44 .  
         [0020]     At the installation location, the wires assembly  15  providing the wires  16 ,  17 ,  45  is run through a suitable length of the conduit  18 , the weight  24  and its pipe  26  are installed on the conduit  18  at a suitable location, and the wire assembly  15  is passed through the nipple  22  and knotted. The wire nuts  50  are attached to the metal conductors of the wires  16 ,  17 ,  45 ,  40 ,  42 ,  47 . The rubber boot  52  is then attached to the nipple  44  and to the end cap  56  and the underwater light  10  is placed in the water. In the event the water is very shallow, a rigid PVC ell (not shown) is attached to the nipple  22  and the weight  24  is positioned near the opposite end of the ell (not shown) to keep the light  10  near the bottom of the water.  
         [0021]     An important feature of this invention is the ability to easily replace the lamp  12 . When the lamp  12  burns out, the homeowner or repairman fishes the light  10  out of the water simply by pulling on the conduit  18 . The clamps  54  are loosened and removed and the nipple  44  is removed from the boot  52 , exposing the wire nuts  50 . The wires electrically connecting the nipple  44  are disconnected by removing the exposed nuts  50 ,  51 . A new lamp/nipple assembly is installed by connecting the wires of the new assembly to the existing wires  16 ,  17 ,  45  with new wire nuts  50 ,  51 . The lamp/nipple assembly is then inserted back into the boot  52  and new clamps  54  are installed and tightened. The light  10  is ready to be placed back in the water. It will accordingly be seen that an important feature of this invention is that the lamp  12  is easy to replace and that, with the exception of the wire nuts  50 ,  51  and burned out bulb, every component of the underwater light  10  is reused thereby minimizing overall costs of this invention.  
         [0022]     Although this invention has been disclosed and described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms is only by way of example and that numerous changes in the details of operation and in the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.