Abstract:
A reflector mounting for fluorescent light fixtures in which a rectangular reflector sheet is formed and held in a trough shape by a series of bracket clips hooked to side edges thereof, the bracket clips having a hole receiving the light tube to thereby hold the reflector in the light fixture.

Description:
BACKGROUND OF THE INVENTION 
   This invention concerns mounting of reflectors in fluorescent light fixtures. The ability to improve the efficiency of light fixtures has led to adding reflectors above fluorescent light tubes to increase the output of light to save electrical power. 
   A typical installation comprises fixing a metal reflector to the fixture housing with fasteners, the reflector positioned above the fluorescent tubes in the fixture housing. This is a slow, labor intensive process, requiring removal of the light tubes and working overhead standing on a ladder. For commercial installations such as stores, offices, factories, etc., involving hundreds of fixtures, the cost is substantial. 
   In U.S. Pat. No. 5,613,761 issued to the present inventors a lightweight reflector using plastic corrugated material with a foil film facing is described. This reflector can be mounted to the tubes themselves, as described in that patent, using cutouts in end pieces of the reflector. 
   While that mounting and reflector is a considerable improvement over the prior reflectors, the reflector must first be formed into a trough shape by fixing end pieces to the reflector ends, and installation is still time consuming as the formed reflector must be maneuvered properly to secure the same into place on the tubes. 
   In addition, there is a great variety of sizes of tubes and fixtures in use, and it would be advantageous to provide a standardized mounting to fit most or all such light sizes. 
   It is the object of the present invention to provide a reflector mounting arrangement and method for fluorescent light fixtures which makes it simple and quick to install a reflector to a variety of light sizes. 
   SUMMARY OF THE INVENTION 
   The above object and others which will become apparent upon a reading of the following specification and claims are achieved by a using flat rectangular reflector sheet fitting within the fixture housing, preferably constructed of corrugated plastic with a reflective film on one side which is preformed with a series of pairs of aligned notches on each side edge. A plurality of bracket clips preferably of a generally rounded shape and made from clear plastic sheet stock each have a pair of opposing slots extending into each end of the clip bracket. The slots are spaced and angled to receive a respective reflector side edge when the reflector is formed into an arcuate trough. 
   The reflector blank has pairs of aligned slots along its length which may each is received in a clip bracket slot to securely position the reflector on a tube, which is received in a central hole in each bracket clip. 
   The bracket clips may come in different sizes and are formed with a knockout hole to receive different sized light tubes. Inwardly extending tabs partially around the hole and are able to be resiliently bent or twisted to allow the tube to be pushed into the hole past the tab, the tab moving back over the tube to prevent the tube from escaping from the hole. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an inverted reflector held on a fluorescent light tube with a series of bracket clips which also hold the reflector in a trough shape, a fragmentary portion of the light fixture shown in phantom lines. 
       FIG. 2  is an enlarged cross sectional view taken through the inverted reflector of  FIG. 1  showing one of the bracket clips in further detail. 
       FIGS. 3A–3D  show a reflector blank with markings to trim to allow cutting to various length reflectors as indicated in the various views. 
   

   DETAILED DESCRIPTION 
   In the following detailed description, certain specific terminology will be employed for the sake of clarity and a particular embodiment described in accordance with the requirements of 35 USC 112, but it is to be understood that the same is not intended to be limiting and should not be so construed inasmuch as the invention is capable of taking many forms and variations within the scope of the appended claims. 
   Referring to the drawings, the present invention concerns a fluorescent light fixture  10  ( FIG. 1 ) in which one or more fluorescent light tubes  12  are mounted. According to the present invention, a reflector  14  is mounted to the fixture  10  by an arrangement including a series of clip brackets  16  preferably made of a clear plastic sheet material so as to be as unobtrusive as possible and to not obstruct light emanating from the tube  12 . 
   Each bracket clips  16  hold the sides edges of the reflector  14  to form the same in a trough shape and are received on the fluorescent tube  12  to hold the reflector over the tube  12  without any connection to the housing  10 . 
     FIG. 2  shows further details. The reflector  14  is preferably constructed generally as described in U.S. Pat. No. 5,613,761, but other reflectors could be used. A backing of corrugated plastic  18  is slit longitudinally on one side to allow ready forming into a trough shape by bending along the corrugation lines. 
   A reflective film  20  is bonded onto the other side to provide maximum reflection of light emanating from the fluorescent tube  12  to concentrate light directed from the tube in the direction towards the open side of the fixture  10 . 
   Each bracket clip  16  is made from flat plastic sheet stock in a rounded shape having ends  22 . A pair of opposing circumferential slots  24  are recessed into the perimeter of each end  22  angled slightly in convergent directions toward each other. The spacing between the two slots  24  is less than the distance between the two side edges  26  of reflector  14  when the reflector lies flat so that the reflector sheet is formed into a trough shape when the side edges  26  are hooked into a respective slot  24  as shown. The reflector  14  has a series of notches  25  cut into its side edges  26 . The bracket clips  16  are installed in the notches  25  to locate and secure the same. 
   A series of spaced apart bracket clips  16  are installed in this way along the length of the reflector  14  to form a complete trough shape along its length. 
   A central hole  28  is sized to receive the light tube  12 , the hole  28  extending into a gap  30  provided to create two resiliently bendable tabs  32  extending partially around said hole. Either of the bendable tabs  32  can be twisted aside to allow the light tube  12  to be passed into the hole  28  so that the light tube  12  need not be removed from the fixture  10  to install the reflector  14 . 
   A knockout  34  is also formed by arcuate slots  36  and scoring  38  to allow use with larger diameter fluorescent light tubes. 
     FIGS. 3A–3D  show how a single reflector blank  40  can be employed to form various lengths reflectors. 
   A series of the notches  25  are provided sufficient in number to allow two, three or four foot reflectors to be constructed while enabling installation of at least two clip brackets. 
   A series of imprinted or scored cutting guide lines  42  A, B, C are provided on either end, as well as a center guide line  42 D. 
   Two longer reflectors  10 A for four foot strip fixtures can be produced from the uncut blank  40 . 
   By cutting along guide lines  42 A a shorter reflector  10 B is formed for four foot recessed fixtures. 
   By cutting along the next guide lines  42 B and  42 D, a pair of two foot reflectors  10 C are provided, each having two aligned pairs of notches  25  for two bracket clips  16 . 
   By cutting along guide lines  42 C, a three foot reflector  10 D is created with three bracket clips  16  used to form and support the same. 
   Thus, a simple inexpensive arrangement and method for increasing the useful light output of fluorescent fixtures is provided using the reflector and bracket clips as described, which allows quicker and easier retrofitting of light fixtures in the field.