Patent Publication Number: US-6905226-B2

Title: Compact fluorescent light fixture

Description:
This invention relates to lighting fixtures. 
   More particularly, this invention relates to lighting fixtures for compact fluorescent lights. 
   Lamp fixtures for compact fluorescent lights are well known. See my U.S. Pat. No. 5,377,086. Such lamps include compact fluorescent lights that are canted outwardly toward the concave walls of the lamp fixture. Heat dissipation is a particular problem for such lamp fixtures, particularly when amalgam compact fluorescent lights are utilized. The amalgam in compact fluorescent lights is provided for the purpose of providing a relatively stable, constant light output over a temperature range of approximately eighty degrees Centigrade to one-hundred and twenty degrees Centigrade. If the operating temperature of an amalgam compact fluorescent light exceeds about one-hundred and twenty degrees Centigrade, then the light output of the light is significantly degraded. Amalgam compact fluorescent lamps operate most efficiently at an operating temperature of about eighty degrees Centigrade. At operating temperatures in the range of eighty-one to one hundred and twenty degrees Centigrade, the operating efficiency of the lamps decreases by up to about 15%. 
   Conventional lamp fixtures of the type illustrated in U.S. Pat. No. 5,377,086 typically are constructed to operate with forty-two watt compact fluorescent lights. If however, such light fixtures could operate with fifty-seven watt compact fluorescent lights, this would be a distinct advantage because a light fixture with eight fifty-seven watt compact fluorescent lights produces about 34,400 lumens, which is on the order of the 34,000 to 36,000 lumens produced by metal halide lamp fixtures. Compact fluorescent lights are much more efficient than metal halide lamp fixtures. A particular problem with attempting to use fifty-seven watt compact fluorescent lights in a conventional lamp fixture of the type shown in U.S. Pat. No. 5,377,086 is that the fixture typically can not successfully dissipate enough heat to maintain the operating temperature of the lights at less than about one hundred and twenty degrees Centigrade. 
   Accordingly, it would be highly desirable to provide an improved lamp fixture that could utilize fifty-seven watt compact fluorescent lights, and even one hundred and twenty watt compact fluorescent lights, while maintaining the operating temperature of the lights at less than about one hundred and twenty degrees Centigrade. 
   Therefore, it is a principal object of the invention to provide an improved lighting apparatus and system. 
   Another object of the invention is to provide an improved lamp fixture in which high wattage compact fluorescent lights can be operated at desired optimal operating temperatures. 

   
     These and other, further and more specific objects and advantages of the invention will be apparent to those of skill in the art from the following detailed description thereof, taken in conjunction with the drawings, in which: 
       FIG. 1  is a perspective view illustrating the top of the lamp fixture of the invention; 
       FIG. 2  is a section view of the top of  FIG. 1  taken along section line  2 — 2  thereof and illustrating additional construction features thereof; 
       FIG. 3  is a top perspective view illustrating the ballast support of the lamp fixture of the invention; 
       FIG. 4  is a bottom perspective view of the ballast support of  FIG. 3  illustrating additional construction details thereof; 
       FIG. 5  is a section view of the ballast support of  FIG. 3  taken along section lines  5 — 5  thereof and illustrating additional construction details thereof; 
       FIG. 6  is a section view of the ballast support of  FIG. 3  taken along section lines  6 — 6  thereof and illustrating additional construction details thereof; 
       FIG. 7  is a top perspective view illustrating the light support of the lamp fixutre of the invention; 
       FIG. 8  is an inverted side view of the light support of  FIG. 7  illustrating additional construction details thereof; 
       FIG. 9  is a side elevation view illustrating the inner optic member of the lamp fixture of the invention; 
       FIG. 10  is a bottom view of the optic member of  FIG. 9 ; 
       FIG. 11  is a bottom view illustrating the outer optic member of the lamp fixture of the invention; 
       FIG. 12  is a side view illustrating the outer optic member of the lamp fixture of the invention; 
       FIG. 13  is a side section view illustrating the top, the ballast support, the light support, the inner optic member, and the outer optic member of the lamp fixture of the invention assembled; 
       FIG. 14  is an exploded assembly view further illustrating the assembly of the top, the ballast support, the light support, the inner optic member, and the outer optic member of the lamp fixture of the invention; 
       FIG. 15  is a side elevation view illustrating insertion of a ballast in the ballast support of the lamp fixture of the invention; 
       FIG. 16  is a side elevation view illustrating a ballast inserted in the ballast support of the lamp fixture of the invention; and, 
       FIG. 17  is a side elevation section view illustrating insertion of the light sockets in the lamp support of the invention. 
   

   Briefly, in accordance with the invention, I provide an improved lamp fixture. The lamp fixture includes a housing. The housing includes a base end of a first size; a light-emitting end of a second size larger than the first size; a center line extending from the center of the base end to the center of the light emitting end; and, an outer optical surface extending intermediate the base end and the light-emitting end. The light fixture also includes a convex inner optical surface inside the housing extending around the center line; and, a lamp support inside the housing for supporting a plurality of compact fluorescent lights displaced about the center line and the inner optical surface including a plurality of lamp supports angled such that compact fluorescent lights supported thereby extend inwardly toward the light-emitting end at an angle toward the center line, toward the inner optical surface, and away from the outer optical surface of said housing. 
   In another embodiment of the invention, I provide an improved lamp fixture including a dome-shaped housing having a base end of a first size; a light-emitting end of a second size larger than the first size; a center line extending from the center of the base end to the center of the light emitting end; and, an inner surface extending intermediate the base end and the light-emitting end. The lamp fixture also includes a light support inside the housing for supporting a plurality of compact fluorescent lights; ballast mounted inside the dome-shaped housing for each of the compact fluorescent lights; and, an emergency ballast system mounted inside the dome-shaped housing and including a ballast and a battery. 
   In a further embodiment of the invention, I provide an improved lamp fixture. The lamp fixture includes a dome-shaped housing. The housing has a base end of a first size; a light-emitting end of a second size larger than the first size; a center line extending from the center of the base end to the center of the light emitting end; and, an outer optical surface extending intermediate the base end and the light-emitting end. The lamp fixture also includes a light support inside said housing for supporting a plurality of compact fluorescent lights; ballast mounted inside the dome-shaped housing for each of the compact fluorescent lights; and, first vents formed in the lamp fixture such that heat generated by the compact fluorescent lights rises upwardly through the vents past the ballast. 
   Turning now the drawings, which depict the presently preferred embodiments of the invention for the purpose of illustration thereof, and not by way of limitation of the invention, and in which like characters refer to corresponding elements throughout the several views,  FIGS. 1 and 2  illustrate the top  10  of the lamp fixture of the invention. The lamp fixture also includes ballast support  11 , light support  12 , inner optic member  13 , and outer optic member  14 . 
   The outer arcuate surface  30  of top  10 , the outer arcuate surface  40  of ballast support  11 , and the outer arcuate surface  25  of outer optic light-emitting member  14  collectively define and comprise the presently preferred dome-shaped housing of the light fixture of the invention. The shape and dimension of the housing can vary as desired. 
   In  FIGS. 1 and 2 , top  10  includes hollow base end or sleeve  36  shaped and dimensioned to slidably receive an end of a conduit or pipe extending downwardly from the ceiling of a building structure. A set screw (not shown) is turned through internally threaded aperture  37  to secure the end of the conduit inside sleeve  36 . The lamp fixture of the invention can be mounted in any desired orientation. 
   Arcuate outer surface  30  extends outwardly and downwardly from sleeve  36  to circular lip  35 . Lip  35  circumscribes center line  90 . Each point on lip  35  is equidistant from centerline  90 . An inner ring of equally spaced vents  31  is formed through the center area of top  10 . An outer ring of equally spaced vents  32  is also formed through the center area of top  10  and is concentric with the inner ring of vents and with cylindrical sleeve  36 . A ring of equally spaced detents  34  is formed around the peripheral portion of top  10 . Detents  34  facilitate the formation of a plurality of horizontally oriented equally spaced vents  33 . Substantially all points on arcuate outer surface  30  are equidistant from inner surface  37 . The size, shape, dimension, and placement of vents on top  10 —as well as on other parts of the lamp fixture of the invention—can vary as desired. The current placement and configuration of vents is, however, preferred and important for reasons set forth below. Top  10  also includes apertures  38  for receiving externally threaded screws during assembly of the lamp fixture of the invention when top  10  is connected to ballast support  11 . 
   Ballast support  11  is illustrated in  FIGS. 3 to 6  and includes upper edge  54 , lower edge  41 , outer arcuate surface  40 , inner arcuate surface  43 , equally spaced detents  41 , equally spaced horizontally oriented vents (i.e., openings) each formed through the floor of a detent  41 , winged ballast receiving units  46 , and apertures  49 ,  50 ,  51  for receiving externally threaded screws during attachment of support  11  to top  10 . 
   Each aperture  49  to  51  aligns with an aperture  38 . Each ballast receiving unit  46  includes a pair of perpendicular wings  47  and  48 . Each wing  48  has a vertically oriented slot  44  formed therein. Each wing  47  has a vertically oriented slot  45  formed therein. Each wing  47  is coplanar with, spaced apart from, and opposes a wing  48  in another unit  46 . This enables a panel of ballast  15  to be slidably inserted in slots  44 ,  45  of an opposing pair  47 — 48  of wings in the manner illustrated in  FIGS. 15 and 16 . As can be seen in  FIG. 4 , ballast support  11  also includes a plurality of members  52  each including an aperture  53  for receiving a threaded screw during attachment of support  11  to support  12 . 
   The light support  12  is illustrated n  FIGS. 7 and 8  and includes eight (8) cross-shaped equally spaced openings  19  formed therethrough. The distance between each adjacent pair of openings  19  can vary as desired, but is presently greater than two inches, preferably three inches or more, and most preferably four inches or more. The distance between openings  19  is critical. As the distance increases, the amount of metal or other material that is between openings  19  and that comprises support  12  increases. Support  19  functions to conduct more heat away from a lamp seated in a socket in opening  19 . 
   As the amount of metal increases, the heat sink capability of support  12  increases and tends to function to enable a light to operate at a lower temperature in the lamp fixture. As is illustrated in  FIG. 17 , a light socket  17  is mounted in each opening  19  in conventional fashion using a wire clip  18  or other means to secure socket  17  in opening  19 . Each socket  17  is connected to a ballast  15  in conventional fashion. Electricity from a battery or other source is supplied to ballast  15  and its associated light  16  in conventional fashion. A compact fluorescent light  16  is inserted in and connected to a socket  17  in conventional fashion. 
   Light support  12  includes upper circular edge  70  and lower circular edge  62 . A first inner circle of equally-spaced vents  60  is formed along a first inner ridge  63 . A second outer circle of equally-spaced vents  61  is formed along a second outer ridge  64 . The use of ridges  63  and  64  is preferred in the invention because, as will be described, it facilitates the upward flow of heat away from lights  16  mounted on support  12 . Upper sloped surface  65  co-terminates at ridge  63  with upper sloped surface  66 . Upper sloped surface  67  co-terminates at ridge  64  with upper sloped surface  65 . Equally spaced apertures  69  can received threaded screws during the attachment of support  12  to support  11  and the attachment of support  12  to outer optic member  14 . 
   Inner optic member  13  is illustrated in  FIGS. 9 and 10  and includes outer conical convex surface  20 , inner conical concave surface  22 , upper cylindrical lip  23 , and lower circular edge  21  circumscribing a circular opening  21 A. Lip  23  is shaped and dimensioned to slide over circular edge  62  of light support  12 . A set screw is turned through internally threaded aperture(s)  24  to secure member  13  on support  12 . Surface  22  reflects light. Surface  22  can be finely polished to reflect light and radiant heat like a mirror, or, can be less finely polished or surfaced so that a smaller proportion of light is reflected. 
   Outer optic member  14  is illustrated in  FIGS. 11 and 12  and includes flat circular upper edge  28  with apertures  28 A formed therethrough to receive screws used to fasten member  14  to ballast support  11  so edge  28  is adjacent edge  41  in the manner illustrated in  FIGS. 13 and 14 . Member  14  also includes lower edge  26 , outer arcuate surface  25 , and inner concave arcuate optical surface  27 . Substantially each point on surface  25  is equidistant from surface  27 . Surface  27  can be finely polished to reflect light and radiant heat like a mirror, or, can be less finely polished or surfaced so that a smaller portion of light is reflected. Top  10 , ballast support  11 , light support  12 , inner optic member  13 , and outer optic member  14  can be made from an opaque material, from a translucent material, from a transparent material, or from any desired material. It is presently preferred that top  10 , ballast support  11 , light support  12  be fabricated from cast aluminum or another metal that functions to absorb heat and to conduct heat away from lights  16  mounted in the lamp fixture of the invention. Inner and outer optic members  13  and  14  can also, if desired, be fabricated from metal. 
   As earlier noted,  FIGS. 13 and 14  illustrate the assembly of the components of the lamp fixture shown in  FIGS. 1 to 12 . 
   One particular advantage of the lamp fixture of the invention is that it enables the base and socket of each light  16  to be spaced farther apart from any adjacent light  16 . In conventional lamp fixtures for compact fluorescent lights, the sockets are spaced one and a half to two inches apart. Spacing the sockets further apart is difficult because the lamp fixtures rapidly become too large and unsightly. The lamp fixture of the invention can readily space the light sockets four inches apart because the lights are tilted inwardly away from the inner optical concave surface  27  of the outer optic member. 
   Another particular advantage of the lamp fixture of the invention is that it more efficiently produces light because it utilizes an inner optic member  13  having a convex light reflecting surface  20 . 
   A further advantage of the lamp fixture of the invention is that it more efficiently removes heat from the vicinity of each light  16 . One reason for this is the ability, noted above, to space light sockets  17  farther apart, allowing a greater volume of heat sink material in light support  12  to absorb and conduct away heat. Another reason for this are the vents  60  formed in light support  12  above each opening  19  so heat travels upwardly over surface  81  into vents  60  (as indicated by arrow D in  FIG. 13 ). Another reason for the improved heat dissipation quality of the lamp fixture is the formation of vents  61  in ridge  64 . A portion of the heat produced out near the distal end of a light  16  rises upwardly into and through vents  61  (as indicated by arrow F) and is not trapped inside the light fixture. Sloped surfaces  81 ,  82  upwardly direct rising heat into and through vents  60 . Sloped surface  80  directs heat downwardly and laterally (as indicated by arrow E) away from surface  71  into and through vents  61 . Vents  42  formed in ballast support  11  also, as indicated by arrow G, facilitate the removal of heat from inside the lamp fixture. Vents  33  (as indicated by arrow H in  FIG. 1 ) similarly facilitate the removal of heat. 
   Still another feature of the lamp fixture that facilitate heat removal is the flow or movement of air on either side of a ballast  15  panel installed in opposing pair  47 — 48  of wings  46 . As indicated by arrow B in  FIG. 13 , some of the heated air rises upwardly past the front side  15 A of a ballast  15  panel. On the other hand, arrow C indicates heated air rising upwardly past the back side of the ballast  15  panel. This occurs because the circular path or curvature of ridge  63  causes some of vents  60  to be on one side of ballast  15  and others of vents  60  to be on the other side of ballast  15 . Vents  61  also direct heated air past ballast  15  in the manner indicated by arrow A in  FIG. 13 . Finally, heated air which rises into the space circumscribed by top  10  flows out through vents  31  and  32  in the manner indicated by arrows I and J in  FIG. 13 . The more efficient heat dissipation functioning of the lamp fixture of the invention enables larger wattage amalgam compact fluorescent lights to be used in the lamp fixture. For example, eight (8) fifty-seven watt amalgam compact fluorescent lights can be utilized in the light fixture illustrated in the drawings. The ability of the lamp fixture of the invention to house efficiently such large wattage compact fluorescent lights means that compact fluorescent lights, which are significantly more efficient than metal halide lights, can be used to light football fields, baseball fields, and other large areas for sporting and other events. 
   Still a further advantage of the lamp fixture of the invention is that a single housing contains both the compact fluorescent lights and the ballast necessary for the lights. Each ballast can operate one or more compact fluorescent lights. 
   Yet another advantage of the lamp fixture of the invention is that a single housing contains the compact fluorescent lights, the ballast for the lights, and the emergency ballast system. The emergency ballast system, including ballast and a battery, is indicated in  FIG. 3  on support member  11  in  FIG. 3  by dashed lines  95 . A switch or other means for testing or activating the emergency ballast system (in the event electrical power is lost during a storm, etc.) can be mounted in opening  21 A of inner optic member  13 . A light fixture constructed in accordance with the invention need not, if desired, include an emergency ballast system. 
   Yet a further advantage of the lamp fixture of the invention is that the inward tilt of the compact fluorescent lights  16  enables the spacing between the sockets  17  to be increased without having to increase the diameter or size of the outer housing of the lamp fixture. In  FIG. 17 , each light  16  is tilted inwardly toward inner optic member  30  and centerline  90  and, consequently, is tilted away from outer optic member  14  and from the inner surface  27  of the outer optic member  14 . The angle M between centerline  90  and the longitudinal axis  90 A of a compact fluorescent light  16  installed in a socket  17  is in the range of forty degrees to eighty degrees, preferably fifty to seventy degrees, and most preferably thirty-five degrees to sixty-five degrees. In  FIG. 17 , axis  90 A is parallel to the outer conical surface of member  30 , but need not be. The angle, if any, between a light  16  and surface  20  can be adjusted as desired. The angle of the outer conical surface  20  of member  30  is canted with respect to axis  90  at an angle N that is in the range of twenty degrees to eighty degrees, preferably thirty degrees to seventy degrees, and most preferably forty degrees to sixty degrees. The majority of light from a light  16  that is downwardly reflected from the light fixture of the invention is reflected off surface  20  of member  30 . 
   Having described the presently preferred embodiments and best mode of the invention in such terms as to enable those of skill in the art to understand and practice the invention,