Patent Publication Number: US-7217007-B2

Title: Dark sky friendly lamp and housing combination apparatus

Description:
TECHNICAL FIELD 
   The present invention relates to lamps. More particularly, the present invention relates to a dark sky friendly lamp-housing combination that is designed to reduce light pollution and light trespass. 
   BACKGROUND OF THE INVENTION 
   Effective outdoor lighting benefits us in many ways. It can be used to increase pedestrian and vehicular safety, enhance a community&#39;s night time character, advertise commercial businesses and provide security. Appropriately designed and properly installed, outdoor lighting contributes to the safety and welfare of everyone. However, inappropriate outdoor lighting applications result in glare, over lighting, light escalation, sky glow and wasted energy. In many parts of the country, the beautifully star lit dark sky cannot be seen due to uncontrolled exterior lighting that results in too much light pollution. 
   The sources of light pollution and light trespass typically include light projected above a horizontal plane or light reflected from illuminated surfaces such as roadways. An increasing number of towns and municipalities have been involved in the alteration of the use of exterior lighting by instituting laws and ordinances. One of the “dark sky friendly™” solutions used by these towns and municipalities involves restricting the illumination direction of exterior lights. In the context of the present patent application, the phrase “dark sky friendly” means that a light illumination is directed in such a way as to reduce light pollution or light trespass or both. 
   Dark sky friendly lighting devices use only “good nighttime” lighting for all applications. With good nighttime lighting, everyone wins. It helps to preserve dark skies, helps people to see better at night, has a more pleasant and comfortable nighttime environment, and potentially saves a great deal of energy and money. 
   Several dark sky friendly luminaries (lighting fixtures) currently exist in the marketplace. The fixtures usually contain a shield within the fixture base to allow shielding of light. These fixtures can be used with any basic light bulb. However, these fixtures are often an expensive option for consumers. In many cases, the entire existing fixtures need to be replaced to make the whole lighting system dark sky friendly. 
   Therefore, it is desirable to provide improved inexpensive dark sky friendly lighting without the need to replace any existing fixtures. 
   SUMMARY OF THE DISCLOSURE 
   A dark sky friendly lamp-housing combination according to the present invention is provided. The combination uses a light bulb having a light element and a base section. A connector of the base section is adapted to be received in a socket of a light fixture. A housing is attached to the base section of the lamp, rather than to a light fixture, and is adapted to direct light from the light bulb. 
   In one embodiment, the housing is rotatably attached to the lamp base section so that the direction of illumination can be adjusted as desired. 
   The present invention provides an inexpensive device that can be used anywhere a standard base bulb is used. Moreover, the lamp-housing combination of the present invention allows any existing light fixture to become dark sky friendly. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a compact fluorescent lamp-housing combination in an unassembled state according to the present invention. 
       FIG. 2  illustrates the compact fluorescent lamp-housing combination of  FIG. 1  with a partially assembled housing according to the present invention. 
       FIG. 3  illustrates the compact fluorescent lamp-housing combination of  FIG. 1  in a partially assembled state according to the present invention. 
       FIGS. 4A and 4B  illustrate an alternative embodiment of a compact fluorescent lamp-housing combination according to the present invention. 
       FIG. 5A  illustrates a perspective view of a ring that rotationally couples the housing to the lamp of  FIG. 1  according to the present invention, and  FIG. 5B  is a vertical cross-sectional view of  FIG. 5A  along line  5 A— 5 A according to the present invention. 
       FIGS. 6A and 6B  illustrate perspective and plan views of the housing of the lamp of  FIG. 1  according to the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As shown in  FIG. 1 , a lamp-housing combination  10  includes a lamp  12 , ring  14  and a rotating housing  16 . Except for a threading portion, the lamp  12  shown is a standard compact fluorescent lamp having a fluorescent light element  18  and a base section  21  that includes a neck (base housing)  20  and a connector (lamp base)  22 . The neck  20  is permanently attached to the connector  22  and receives the ends of the fluorescent light element  18 . As is well-known, the neck  20  typically houses circuitry including a ballast through which electricity passes to produce light in the light element  18 . The connector  22  is designed to electrically (through metal contacts) and physically (by the thread) be connected to a socket of a light fixture (not shown). 
   The housing  16  includes a U-shaped plastic shell  24 , a light reflector  26  made of reflective metal and disposed on the inner wall of the shell  24 , and a removable cap  28  that slides over the light element  18  to block any light in the vertical (axial) direction. If the lamp  12  is to be used in a base-down fixture, the removable cap blocks any light that projects upward. On the other hand, if the lamp  12  is to be used in a base-up fixture, the removable cap may be removed. The removable cap  28  has a groove  30  that slides over and locks with a rib  32  disposed at the top of the shell  24  to provide a tight fit. The width of the cap  28  is slightly higher than the width of the housing  26  slot so that the groove  30  and rib  32  form a friction fit or lock to prevent the cap from sliding out. 
   As shown in  FIG. 6 , the housing  16  has a lateral opening  34  that guides light illumination within a predetermined lateral range of angles. The angle range is preferably between 60 degrees and 80 degrees relative to the longitudinal axis  36  of the lamp  12 . As shown in  FIG. 6 , the angle range is 70 degrees relative to the longitudinal axis  36  and 45 degrees relative to the backside of the housing shell  24 . 
   The ring  14  (see  FIGS. 1 and 5 ) has an inner threading portion that screws tightly onto the threading portion of the neck  20 . Consequently, the ring  14  is threadably coupled to the neck  20  of the light bulb  12 . As shown in  FIG. 5 , the ring  14  has a rim  38  that locks into a groove  42  of the housing shell  24  by pushing the ring toward the housing. Once the rim  38  is locked into the groove  42 , the shell  24  is rotatable relative to the lamp  12 . A rotation stop  40  in the outer side of the ring  14  interacts with a rotation stop  44  of the housing shell  24  to prevent the shell from rotating fully (360 degrees or more) around the lamp  12 . This allows the ring  14  to be threaded into the exterior threading of the neck  20  by rotation of the housing  24 . The total lengths of the rotation stops  40  and  44  define the restricted angular movement. As shown in  FIGS. 5 and 6 , the length of the two stops  40  and  44  corresponds to about 10 degrees relative to the longitudinal axis  36  of the lamp  12 . Thus, the rotation stops  40  and  44  limit rotational movement of the housing  16  to a predefined angular range of about 350 degrees. Preferably, the predefined angular range is at least about 180 degrees. However, the lengths of the stops  40  and  44  and the number of stops can be varied to provide a desired rotational range. 
   Once the rim  38  of the ring  14  locks into the groove  42  of the housing shell  24 , the housing is screwed onto the neck  20  of the lamp  12  through the inside threading of the ring  14 . The threading of the ring  14  into the neck  20  is aided by the rotation stops  40  and  44  which prevent rotation of the housing with respect to the ring. Once the ring  14  is fully threaded into the neck  20 , the ring allows the housing  16  to rotate 350 degrees in either circumferential direction. The removable cap  28 , as shown in  FIG. 3 , is then slid into the rib  32  of the housing  16  by the groove  30  in the cap. 
     FIG. 4  illustrates an alternate embodiment of the present invention in which similar parts are identified with the same reference numerals as that of the lamp-housing combination  10  of  FIG. 1 . A lamp-housing combination  50  of  FIG. 4  is designed to be primarily used in base-up fixtures, e.g., flood light fixture designed to direct light downwardly. A plastic cone shaped housing  16  has a light reflector  26  on the inside wall. The light reflector  26  as shown in  FIG. 4  is a reflective aluminized coating. One end of the housing  16  has an inner thread that screws onto the neck  20  of the lamp  12 . 
   According to the present invention, the housing  16  that is designed to be attached directly to the lamp  12  rather than as an add-on to a light fixture or as part of the fixture provides an inexpensive device that can be used anywhere a standard base bulb is used. Moreover, the lamp-housing combination of the present invention allows any existing light fixture to become dark sky friendly. 
   The foregoing specific embodiments represent just some of the ways of practicing the present invention. Many other embodiments are possible within the spirit of the invention. Accordingly, the scope of the invention is not limited to the foregoing specification, but instead is given by the appended claims along with their full range of equivalents.