Abstract:
A retrofit unit for a fluorescent lighting fixture having a chamber with a ballast and a plurality of downwardly extending lamp holders for enclosing an existing fluorescent strip light fixture, wherein neither the ballast nor the lamp holders of the existing fluorescent lighting fixture need be removed to receive this retrofit unit.

Description:
CROSS-REFERENCE TO PRIOR APPLICATION  
       [0001]    This application claims priority to U.S. Provisional Patent Application Serial No. 60/429,921, filed on Nov. 30, 2002. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to surface mount fluorescent strip light fixtures, and, more particularly, to a retrofit kit and method of retrofitting for surface mount fluorescent strip light fixtures.  
           [0004]    2. Description of Related Art  
           [0005]    Surface mount fluorescent strip light fixtures are installed to provide general lighting of large indoor spaces. It should be understood that the description of the fixtures as ‘surface mount’ type fixtures is intended to distinguish the fixtures from ‘recessed’ type fixtures. Thus, the invention taught herein will apply to all ‘surface mount’ type fluorescent strip light fixtures, including stem and pendant mounted suspended variations as well as those fixtures mounted directly to a ceiling.  
           [0006]    Typically, such strip fixtures include a channel in the form of an inverted trough, with the channel being attached to the ceiling. Lamp holders (sockets) are attached to the channel. A ballast is attached within the channel and wiring attaches the ballast to the lamp holders. Power is supplied to the ballast by wiring brought into the channel through the top or end of the channel. A ballast cover is used to close the open face of the channel so that the ballast and wiring are enclosed. Linear fluorescent lamps are then placed in the lamp holders for operation of the fixture. The lamps are left bare and exposed for providing light to the space. Because of their low cost and utilitarian use, the surface mount fluorescent strip light fixture is the best selling light fixture of all time. Thus, as used herein, surface mount fluorescent strip light fixtures shall be understood to include all fixtures having this basic configuration.  
           [0007]    Typical uses include retail stores, such a grocery, drug, and department stores, where the fixtures are commonly mounted in continuous rows. The fixtures are also used in warehouses.  
           [0008]    Since the introduction of the fluorescent lamp at the 1939 World Fair, fluorescent lighting technology has greatly advanced. Particularly in response to the energy crisis of the 1970&#39;s and the National Energy Policy Act of 1992, lamp and ballast manufacturers have developed fluorescent lamp-ballast systems with improved efficiencies. For example, electronic ballasts are now capable of more efficient operation than older technology magnetic ballasts. Additionally, the newer, energy saving fluorescent lamps have special lamp holder and/or ballast requirements.  
           [0009]    There are a large number of fixtures in the market that use obsolete technology. Consumers desire to reduce their utility costs, and the newer technology can save 25%, or better, in such costs. However, for existing installations, implementation of the newer technology means either replacing the individual fixture components (ballast, lamp holders, wiring, and lamps) or replacing the fixtures all together. Both processes are time consuming and labor intensive, requiring 30 minutes or so for each fixture retrofit or replacement. Further, the retrofit process requires closing down sections of a store during the construction, increasing the impact of the time and effort required to retrofit or replace the old fixtures. Thus, there is a need for a retrofit kit and method for surface mount fluorescent strip light fixtures that can be installed with a minimum of time and labor.  
           [0010]    Additionally, current retrofit or replacement options for old fixtures requires disposal of the old ballast, lamp holders, wiring, and lamps, or the entire fixture all together, creating disposal costs and other issues. For instance, many old ballasts contain hazardous materials and require disposal treatment as such. Thus, there is a further need for a retrofit kit and method for surface mount fluorescent strip light fixtures that minimizes the disposal issues of the retrofit process.  
         BRIEF SUMMARY OF THE INVENTION  
         [0011]    Thus, it is an object of the present invention to provide a retrofit kit and method of retrofitting existing fluorescent strip light fixtures with a replacement lamp-ballast system.  
           [0012]    It is a further object of the present invention to provide a kit and a method for retrofitting an existing fluorescent strip light fixture that can be installed with a minimum of time and labor.  
           [0013]    It is even a further object of the present invention to provide a retrofit kit for an existing fluorescent strip light fixture that minimizes the disposal issues of the retrofit process.  
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 shows an exploded view of an existing surface mount fluorescent strip light fixture  
         [0015]    [0015]FIG. 2 shows a partial perspective view of an existing surface mount fluorescent strip light fixture and a retrofit kit according to the present invention, particularly showing a mounting bracket attached to the existing fixture in alignment with slots in a retrofit channel.  
         [0016]    [0016]FIG. 3 shows a perspective view of an existing surface mount fluorescent strip light fixture and the retrofit kit of the present invention, particularly showing the retrofit channel hanging on the mounting brackets.  
         [0017]    [0017]FIG. 4 shows a different perspective view of the arrangement of FIG. 3, particularly showing the ballast and ballast wiring of the retrofit kit of the present invention. FIG. 4 is show with the second side wall door removed so that the wiring details are more clearly visible.  
         [0018]    [0018]FIG. 5 shows a partial perspective view of an existing surface mount fluorescent strip light fixture and the retrofit kit of the present invention, particularly showing the retrofit kit swung into position around the existing fixture.  
         [0019]    [0019]FIG. 6 is a partial perspective view of the mounting bracket and door section outwardly turned flange of FIG. 5.  
         [0020]    [0020]FIG. 7 is another view of the components of FIG. 6, with the thumb latch rotated into engagement with the door section flange. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    As shown in FIG. 1, an existing surface mount fluorescent strip light fixture  10  has an existing strip channel  12  in the form of an inverted trough, with the existing channel  12  being attached to a ceiling  14 . As mentioned earlier, surface mount type fluorescent strip fixtures may also be suspended from a ceiling by a stem or other pendant type suspension system, and it should be understood that the principles taught herein will apply equally to any surface mount type fluorescent strip fixture whether it is suspended or mounted directly to a ceiling. The existing channel  12  has a width, w, as shown, which is typically around 4⅛ inches to 4¼ inches. The existing fixture  10  has lamp holders  16  which are commonly attached to a saddle piece  18 , which is, in turn, suspended between the walls of the existing channel  12 . The existing fixture also has a ballast  20 , which is contained within the existing channel  12 . Power is supplied to the ballast by power supply leads  22  brought into the channel  12 , and the ballast  20 , in turn, provides power to the lamp holders  16  by existing lamp holder wiring  24 . A ballast cover  26  covers the open face of the existing channel  12  to enclose the ballast  20 , power wiring  22  and lamp holder wiring  24 .  
         [0022]    Preparation of the existing strip fixture  10  for retrofitting with the retrofit kit and method of the present invention includes: disconnecting power to the existing strip fixture  10 ; removing the existing lamps (already removed from the existing fixture shown in FIG. 1); and removing the ballast cover  26 . The existing lamps and the ballast cover  26  will be the only components of the existing strip fixture  10  which require disposal in the retrofit process according to the instant invention.  
         [0023]    As shown in FIGS.  2 - 7 , the surface mount fluorescent strip light fixture retrofit kit of the present invention is comprised of two mounting brackets  28  and a retrofit channel  30 . The brackets  28  attach to the existing strip channel  12 . The retrofit channel  30  hangs from the brackets  28  and wraps around the remaining components of the existing fixture  10 .  
         [0024]    More specifically, as shown in FIG. 2, each mounting bracket  28  has a horizontal arm  32 , a depending leg  34 , and an upturned hook section  36 . The horizontal arm  32  has a first end  38  and a second end  40  and a length,  1 , which is longer than the width, w, of the existing channel  12 . The depending leg  34  extends downward from the first end  38  of the horizontal arm  32  and conforms generally to the shape of the channel  12 . The upturned hook section  36  extends upward and outward from the bottom end of the depending leg  34 , forming a hook-like structure therewith. The depending leg  34  contains a fastener hole  42 . Preferably, the mounting brackets are made of a heavy gauge ( 16  gauge or  18  gauge) galvanized steel for strength.  
         [0025]    The retrofit channel  30  has the form of a non-inverted trough, generally, having a first side wall  44 , a bottom wall  46 , and a second side wall  48  (shown only partially in FIG. 2). As mentioned earlier, the retrofit channel  30  is proportioned to wrap around the existing fixture  10 , including the existing channel  12 , lamp holders  16 , and ballast  20  without the need to remove or dispose of those components. The first side wall  44  of the retrofit channel  30  has an upper end  50  with slots  52  formed therein. The slots  52  are each configured to receive the upturned hook section  36  of the mounting brackets  28 .  
         [0026]    As shown in FIG. 3, multiple slots are formed along the upper end  50  of the first side wall  44 .  
         [0027]    Thus, the mounting brackets  28  are installed to the existing channel  12  by slipping each bracket  28  between the ceiling and the existing channel  12  so that the upturned hook section  36  lines up with a slot  52  in the retrofit channel  30 , as shown in FIG. 2. A template may be utilized for this alignment, or the installer may simply use a ruler or other measuring device to make the alignment. Should the selected position for installation of a bracket  28  be obstructed by a fastener connecting the existing channel  12  to the ceiling, or a boss on top of the existing channel  12 , an alternate location may be easily selected by relocating the mounting bracket  28  to an alternate location free of obstructions that lines up with an alternate slot  52 . Should the existing fixture  10  have a suspended mounting arrangement, the mounting brackets can just be laid on top of the existing channel  12 . Should the existing channel  12  be mounted so close to the ceiling that the mounting brackets  28  will not fit in the space between the existing channel  12  and the ceiling, the bracket may be driven through the space with a hammer. Following positioning of the mounting brackets  28  on top of the existing channel  12 , small pilot holes may be created in the existing channel  12  in alignment with the fastener holes  42  in the depending legs  34  of each mounting bracket  28 . Thus, the mounting brackets  28  may be fastened to the existing channel  12  with fasteners, such as screws  54  through the fastener holes  42  and the pilot holes.  
         [0028]    Upon fastening of the mounting brackets  28  to the existing channel  12 , the retrofit channel  30  may be hung by the slots  52  on the upturned hook sections  36  of the mounting brackets  28 , as best shown in FIG. 3.  
         [0029]    As shown in FIG. 4, a retrofit ballast  56  and retrofit lamp holders  58  are attached to the retrofit channel  30 , and are connected by retrofit lamp holder wiring  60 . The design of the retrofit kit and method of retrofitting of the present invention enables attachment of the retrofit ballast  56  and lamp holders  58 , and the connection of the retrofit lamp holder wiring  60  to be performed during the manufacturing of the kit at the factory. Thus, the installer of the kit at the retrofit site does not have to devote time or labor to these tasks.  
         [0030]    As further shown in FIG. 4, the retrofit ballast  56  has power leads  62  and the retrofit kit has a ground lead  64 .  
         [0031]    The next step in installation of the retrofit kit is to disconnect the power supply leads  22  from the existing ballast  20  and connect the power supply leads  22  to the retrofit ballast power leads  62 . Additionally, the retrofit kit ground lead  64  should be connected to a through feed ground wire or other ground wire in the existing fixture.  
         [0032]    The mounting bracket upturned hook section  36  and retrofit channel slots  52  create a hinge that allows the retrofit channel  30  to hang from the mounting brackets  28  in a position such that interior portion of the retrofit channel  30  is accessible to the installer for making the described electrical connections, as shown in FIGS. 3 and 4.  
         [0033]    Further facilitating access to the installer for making the electrical connections, the retrofit channel second side wall  48 , best shown in FIG. 5, can be fabricated as having a door section  66  and a lower section  68 . In the embodiment shown, the door section  66  is hinged to the lower section  68  through the use of a plurality of T-slots  70  along the upper end of the lower section (see FIG. 4) and mating hooks (not shown) formed along the lower edge of the door section  66 . This hinged arrangement of the door section  66  and lower section  68  of the second side wall  48  enables the door section  66  to be opened for easier access to the interior portion of the retrofit channel  30 .  
         [0034]    It should be observed that the door section  66  has been removed from the views of FIGS.  2 - 4  in order to more clearly show the component details of those views. Thus, FIGS.  2 - 4  show only the lower section  68  of the second side wall  48  of the retrofit channel  30 . However, it should be understood that the second side wall  48  of the embodiment shown includes both the lower section  68  and the door section  66 .  
         [0035]    Returning now to the view of FIG. 5, it is seen that the top portion of the door section  66  has an outwardly turned flange  72 . Thus, after the wiring connections are completed, the retrofit kit may be swung up such that the door section flange  72  seats against the underside of the mounting bracket second ends  40  (only one mounting bracket  28  shown in FIG. 5).  
         [0036]    As best shown in FIGS. 6 and 7, the underside of each mounting bracket second end  40  has a thumb latch  74  rotatably attached thereto by a rivet  76 . Thus, the thumb latch  74  of each mounting bracket second end  40  may be rotated out of the way of the door section flange  72  so that it may seat against the underside of each mounting bracket second end  40 . Then, the thumb latch  74  of each mounting bracket second end  40  may be rotated so that it engages the under side of the door section flange  72 , thereby holding the door section  66 , and the retrofit channel  30  in place, as shown in FIG. 5.  
         [0037]    As further shown in FIG. 5, the retrofit kit may include end caps  78  which are configured to close the ends of the retrofitted fluorescent strip light fixture, or the ends of a row of retrofitted fixtures. The end caps  78  may be attached to the assembly by any convenient means.  
         [0038]    Continuing with the view of FIG. 5, it is seen that the wrap around arrangement of the retrofit channel  30  and the existing channel  12  and existing lamp holders  16  creates a chamber  80  for the retrofit ballast  56  and associated wiring (see FIG. 4) without requiring the removal of the existing ballast  20  (and the associated disposal issues) and associated wiring (see FIG. 1).  
         [0039]    Additionally, as shown in FIG. 5, the wrap around arrangement allows the retrofit channel bottom wall  46  to be wider than the existing channel  12 . Thus, on the embodiment shown, the bottom wall may have a flat portion  82  in the middle and angled portions  84  on either side of the flat portion. This allows improved optical performance in the two-lamp configuration shown. Additionally, this allows one-lamp and three-lamp versions of the retrofit kit to be produced by installation of lamp holders and a lamp on the flat portion  82  of the bottom wall  46 .  
         [0040]    Returning now to FIGS. 6 and 7, the embodiment of the invention shown also has a fastener hole  86  located in the thumb latch. Each mounting bracket second end  40  further has a fastener hole  88  positioned to be in alignment with the thumb latch fastener hole  86  when the thumb latch  74  is rotated into engagement with the door section flange  72 . Additionally, fastener holes  90  are located at positions in the door section flange  72  corresponding to the slots  52  in the first side wall  44  such that the fastener holes  90  will be in alignment with the thumb latch fastener hole  86  and the mounting bracket second end fastener hole  88 . Thus, a fastener  92 , such as a screw, may be fastened through thumb latch fastener hole  86 , flange fastener hole  90  and mounting bracket second end fastener hole  88  to secure the thumb latch  74  in place and to establish electrical ground continuity between the respective components.  
         [0041]    Returning now to FIG. 2, the embodiment of the invention shown also has a groove  94  positioned along the upper end  50  of the retrofit channel first side wall  44  such that the slots  52  are located at the bottom of the groove  94 . This configuration enables the installer to more easily position each mounting bracket upturned hook section  36  in a first side wall slot  52  for hanging the retrofit channel  30  from the mounting brackets  28 . Additionally, this configuration allows the first side wall groove  94  to seat against the existing channel  12  in order to meet code requirements.  
         [0042]    The material of the retrofit channel  30  of the embodiment shown and described is code gauge steel (26 gauge to 16 gauge). However, it should be noted that the retrofit channel  30  does not require the attachment of conduit thereto, allowing selection of a thinner gauge material to meet code requirements and providing for savings in material costs. The retrofit channel may be formed on a press break, roll formed, or formed by any other suitable method.  
         [0043]    This description of the invention, including specific dimensions and materials, shall not be construed as a limitation of any invention hereafter claimed by the inventors, as it will be readily apparent to those skilled in the art that design choices may be made without departing from the spirit or scope of the invention.