Patent Publication Number: US-7905626-B2

Title: Modular lighting apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of the U.S. Provisional Patent Application Ser. No. 61/003,675, filed Nov. 19, 2007; U.S. Provisional Patent Application Ser. No. 61/003,702, filed Nov. 19, 2007; and U.S. Provisional Patent Application Ser. No. 60/965,027, filed Aug. 16, 2007, the entire scope and content of all of which is hereby incorporated herein by reference for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to lighting apparatus and, in particular, to replaceable light bulbs for use in screw-socket light fixtures. 
     BACKGROUND OF THE INVENTION 
     Conventional screw-base incandescent bulbs remain the primary source of household electrical illumination. Compact fluorescent lamps (CFLs) with screw bases have been developed for household use, and they are much more efficient than incandescent bulbs. But CFLs currently account for only about 5 percent of the market for household electrical illumination bulbs, with all (or substantially all) of the remaining 95 percent being incandescent bulbs. One major reason that CFLs have not gained wider acceptance is that, relative to incandescent bulbs, they cost significantly more. 
     Accordingly, it can be seen that a need exists for improvements in CFLs to make them more affordable. It is to such solutions that the present invention is primarily directed. 
     SUMMARY OF THE INVENTION 
     Generally described, the present invention provides a modular lighting apparatus that includes a replaceable bulb assembly, an adapter, and a mechanical and electrical connector assembly that removably connects the bulb assembly to the adapter for use. The bulb assembly includes a light-emitting component mounted to a body. And the adapter includes a standard screw base mounted to a body that houses an electronic ballast, which is electrically connected to the screw base. When assembled with the bulb assembly and adapter bodies connected together, the ballast is electrically connected to the light-emitting component by way of the electrical connectors. 
     In a first example embodiment the light-emitting component includes a spiral-tube CFL. In this embodiment the lighting apparatus fits in most existing household lighting fixtures. The combination of the adapter including the screw base, the adapter including the electronic ballast, and the connector assembly enabling the bulb assembly to be replaceable on the adapter provides significant advantages over known lighting systems. In particular, a major cost of conventional CFLs is the electronic ballast, which is discarded when the bulbs burn out even though the ballasts normally have much more life left in them. With the electronic ballast being integral to the adapter, however, when the bulb assembly reaches the end of its useful life it can be removed from the adapter and replaced with a fresh bulb assembly. So the electronic ballast can be reused with new bulb assemblies, thereby saving money and avoiding waste and environmental contamination. In addition, with the adapter also including the screw base, the lighting apparatus can be used with existing standard screw-socket light fixtures without any retrofitting or replacement work. So widespread household use can be made of the lighting apparatus, thereby contributing to significant cost savings for the public as well as energy savings, reduced pollution, and less dependence on foreign energy supplies. 
     In a second example embodiment the light-emitting component includes a transversely arranged CFL tube. In this embodiment the lighting apparatus has the additional advantage of a very low-profile relative to other similar-wattage lighting systems, so it can be more safely used in small spaces such as closets and crawl spaces. 
     In a third example embodiment the light-emitting component includes an omni-directional LED array. And in a fourth example embodiment the light-emitting component includes a primary omni-directional LED array and a secondary omni-directional LED array. In these embodiments the lighting apparatus have the additional advantage of employing high-efficiency LEDs in arrangements that disperse light to illuminate a space, so they are suitable for household use to illuminate rooms. 
     In a fifth example embodiment the adapter mechanically and electrically connects to a commercially available replaceable CFL bulb assembly. In this embodiment the adapter provides the advantage of adapting existing screw-socket light fixtures for use with existing replaceable CFL bulb assemblies that do not include an ballast. 
     And in a sixth example embodiment the adapter body includes an integral photocell. In this embodiment the adapter provides the advantage of automatic on/off control without increasing the overall height of the composite lighting apparatus. 
     These and other features and advantages of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawing figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a modular lighting apparatus according to a first example embodiment of the present invention, showing a replaceable CFL bulb assembly separated from a screw-base adapter with an electronic ballast. 
         FIG. 2  is a bottom view of the bulb assembly of  FIG. 1 . 
         FIG. 3  is a top view of the adapter of  FIG. 1 . 
         FIG. 4  is an exploded perspective view of the adapter of  FIG. 1 , showing the electronic ballast and electrical contacts on the inner surface of the adapter top. 
         FIG. 5  is a perspective view of the modular lighting apparatus of  FIG. 1 , showing a new bulb being installed onto the adapter for use. 
         FIG. 6A  is a front perspective view of a replaceable low-profile bulb assembly of a modular lighting apparatus according to a second example embodiment of the invention. 
         FIG. 6B  is a rear perspective view of the replaceable low-profile bulb assembly of  FIG. 6A . 
         FIG. 6C  is a side view, with a portion shown in cross section, of the replaceable low-profile bulb assembly of  FIG. 6A . 
         FIG. 7  is a perspective view of a replaceable LED bulb assembly of a modular lighting apparatus according to a third example embodiment of the invention. 
         FIG. 8  is a perspective view of a replaceable LED bulb assembly of a modular lighting apparatus according to a fourth example embodiment of the invention. 
         FIG. 9  is a side view of a modular lighting apparatus according to a fifth example embodiment of the invention, showing a conventional replaceable CFL bulb separated from a screw-base adapter with an electronic ballast. 
         FIG. 10  is a perspective view of a modular lighting apparatus according to a sixth example embodiment of the invention, showing a replaceable bulb assembly installed onto a screw-base adapter with an electronic ballast and an integral photocell. 
     
    
    
     DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS 
     The present invention may be understood more readily by reference to the following detailed description of the invention taken in connection with the accompanying drawing figures, which form a part of this disclosure. It is to be understood that this invention is not limited to the specific devices, methods, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention. Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. 
     Referring to the drawing figures,  FIGS. 1-5  show a modular lighting apparatus  10  according to a first example embodiment of the present invention. The lighting apparatus  10  includes a bulb assembly  12 , an adapter  14 , and a connector assembly  16 . The connector assembly  16  functions to permit the bulb assembly  12  to be mechanically and electrically connected to the adapter  14  for use and, when the bulb assembly is not functioning (e.g., from being spent or damaged), to be removed and replaced with a new one. 
     The bulb assembly  12  includes a light-emitting component  18  and a body  20 . The light-emitting component  18  may be provided by one or more compact fluorescent lamp (CFL) tubes or bulbs, other gas-discharge lamp tubes or bulbs (e.g., using neon, argon, krypton, xenon, or other noble gases), light-emitting diodes (LEDs), or other illumination devices that operate in conjunction with an electronic ballast to emit visible light. In the depicted embodiment, for example, the light-emitting component  18  is of the type included in conventional spiral-tube CFLs such as those commercially available from SYLVANIA (Danvers, Mass.) and N:VISION (Aurora, Ohio). As such, the depicted light-emitting component  18  includes a sealed glass tube containing two electrodes, a small amount of mercury, an inert gas (e.g., argon) under low pressure, and a phosphor powder coated along the inside of the tube (the components within the tube are not shown). It should be noted that the term “bulb assembly” as used herein is not limited to bulb-shaped structures. 
     The light-emitting component  18  is mounted to the body  20  of the bulb assembly  12 . The body  20  includes a shell  22 , first mechanical and electrical connectors  24  and  26  of the connector assembly  16 , and electrical connections (not shown) from the electrical connectors to the electrodes of the light-emitting component  18 . The shell  22  is made of a hard plastic or other durable, low-cost material that houses the electrical connections, which are of a conventional type (e.g., wiring). 
     The adapter  14  includes a screw base  28  and a body  30 . The screw base  22  is of a conventional male type for screwing into conventional female-type screw sockets of household light fixtures. Thus, the screw base  28  includes a threaded sleeve contact  34  (also referred to as a “cap”), an end contact  36 , and an insulation section  38  between the contacts (see  FIG. 4 ). In a typical commercial embodiment, for example, the screw base  28  is a standard E26 size (according to the Edison fitting system), though other Edison screw-base sizes such as E10, E12, E14, E17, and E27 may be used. 
     The screw base  28  is mounted to the body  30  of the adapter  14 . The body  30  includes a shell  42 , second mechanical and electrical connectors  44  and  46  of the connector assembly  16 , an electronic ballast  48 , and electrical connections (not shown) from the screw-base contacts  34  and  36  to the electronic ballast to the electrical connectors. The shell  42  is made of a hard plastic or other durable, low-cost material that houses the electronic ballast  48  and the electrical connections, which are of a conventional type (e.g., wiring). 
     The electronic ballast  48  includes a control circuit of a conventional type. In a typical commercial embodiment, for example, the electronic ballast circuit is of the type included in conventional spiral-tube CFLs such as those commercially available from SYLVANIA (Danvers, Mass.) and N:VISION (Aurora, Oh.). In other embodiments, the electronic ballast circuit is of the type disclosed by U.S. Pat. Nos. 7,332,873; 6,911,788; 6,891,339; 6,879,117; 5,341,068; or 4,748,380, all of which are hereby incorporated herein by reference. It will be understood that for convenience the electronic ballast  48  is shown in a block diagram form, which is not a true likeness of this component. 
     The combination of the adapter  14  including the screw base  28 , the adapter  14  including the electronic ballast  48 , and the connector assembly  16  enabling the bulb assembly  12  to be replaceable on the adapter provides significant advantages over known lighting systems. In particular, a major cost of conventional CFLs is the electronic ballast, which is discarded when the bulb burns out even though the ballast normally has much more life left in it. With the electronic ballast  48  of the lighting apparatus  10  being integral to the adapter  14 , however, when the bulb assembly  16  reaches the end of its useful life it can be removed from the adapter  14  and replaced with a fresh bulb assembly. So the electronic ballast  48  can be reused with a number of new bulb assemblies  16  over time, thereby saving a significant amount of money and avoiding unnecessarily contaminating the environment. In addition, with the adapter  14  also including the screw base  28 , the lighting apparatus  10  can be used with existing standard screw-socket light fixtures without any retrofitting or replacement work. So widespread household use can be made of the lighting apparatus  10 , which could contribute to a significant cost savings for the public as well as energy savings, reduced pollution, and less dependence on foreign energy supplies. 
     Furthermore, to aid in starting up quickly, the lighting apparatus  10  may be of an instant-start design, a rapid-start design, or a starter-switch design, all of which are well known in the art and can be readily incorporated by persons of ordinary skill in the art. In addition, the lighting apparatus  10  may include other control components known in the art and readily incorporated by persons of ordinary skill in the art. Preferably, all of these electronic components are housed in the body  30  of the adapter  14  so they can be reused with the electronic ballast  28 . 
     Details of example connector assemblies  16  will now be described. As mentioned above, the connector assembly  16  includes first mechanical and electrical connectors  24  and  26  of the bulb assembly body  20  and second mechanical and electrical connectors  44  and  46  of the adapter body  30 . The first and second electrical connectors  26  and  46  disengageably contact each other to provide a path of electrical continuity for current to flow from the adapter  14  to the bulb assembly  12 . And the first and second mechanical connectors  24  and  44  disengageably couple together to securely fasten the bulb assembly  12  to the adapter  14  for use. 
     For example, the depicted embodiment has two first electrical connectors  26  each including a conductive pin  50  with a head  52  defining a contact  54 , and two second electrical connectors  46  each including a contact  56 . The shell  22  of the bulb assembly body  20  includes a mating panel  58  from which the conductive pins  50  extend, and the shell  42  of the adapter body  30  includes a mating panel  60  defining apertures  62  through which the heads  52  extend so that the first contacts  54  engage the second contacts  56 . The heads  52  have a larger lateral dimension than the pins  50 , and the apertures  62  are curved slots each having an enlarged portion  64  that the heads can fit through and a narrowed portion  66  that the heads cannot fit through. The contacts  56  are provided by conductive pieces (e.g., copper strips) mounted between two retainers (e.g., tabs)  68  and at least partially surrounded by an insulating wall  70 . The retainers  68  and the walls  70  extend inwardly from the inner surface of the adapter mating panel  60 . If desired, the adapter contacts  56  may be spring-biased to impart a force to the bulb contacts  54 . 
     In addition, the depicted embodiment has two first mechanical connectors  26  each including an arm  72  with a head  74 , and two second mechanical connectors  46  each including an aperture  76 . The arms  72  extend from the bulb mating panel  58  and through the aperture  76 , which is defined by the adapter mating panel  60 . The heads  74  have a larger lateral dimension than the arms  72 , and the apertures  76  are curved slots each having an enlarged portion  78  that the heads can fit through and a narrowed portion  80  that the heads cannot fit through. 
     To install the bulb assembly  12  on the adapter  14 , the bulb assembly is positioned adjacent the adapter until the pin-heads  52  insert through the enlarged portions  64  of the curved apertures  62  and the arm-heads  74  insert through the enlarged portions  78  of the curved apertures  76 . Then the bulb assembly  12  and the adapter  14  are rotated relative to each other to move the pins  50  into the narrowed portions  66  of the curved apertures  62  and to move the arms  72  into the narrowed portions  80  of the curved apertures  76 . In this position, the pin-head bulb-side contacts  54  are held in contact with the adapter-side contacts  56  and the arm-heads  74  are restrained from longitudinal movement by the adapter mating panel  60 , so the bulb assembly  12  and the adapter  14  are electrically and mechanically connected together. To later remove the bulb assembly  12  from the adapter  14 , these parts are rotated in the reverse direction (as shown by the directional arrows of  FIG. 5 ) and pulled apart. 
     In other embodiments the mechanical and electrical connector assembly  16  can be provided with other connection components. For example, one alternative embodiment includes combined mechanical and electrical connectors such as the electrical connectors just described, as the heads and the narrowed aperture portions of these connectors provide a mechanical connection. In another alternative embodiment the first electrical connectors are pins without heads that are inserted into apertures without enlarged portions (for electrical connection but not mechanical connection). In yet another alternative embodiment the first and second connectors (electrical, mechanical, or both) are switched between the adapter and the bulb assembly (e.g., the electrical pin extends from the adapter body instead of the bulb assembly body). And in still another alternative embodiment the mechanical connectors include catch elements (e.g., detents) that releasably secure the bulb assembly and the adapter together rotationally. It will be understood that different numbers and/or conventional types of mechanical connector elements, electrical connector elements, or both can be used with good results. 
       FIGS. 6A-6C  show a replaceable low-profile bulb assembly  112  of a modular lighting apparatus according to a second example embodiment of the present invention. The bulb assembly  112  is similar to that of the first example embodiment in that it includes a light-emitting component  118  attached to a body  120  having first mechanical and electrical connectors  124  and  126 . In addition, the bulb assembly  112  is used with an adapter (not shown) similar to that of the first example embodiment, for example, including a screw base and a body with an electronic ballast and with second mechanical and electrical connectors that mate with the first mechanical and electrical connectors  124  and  126 . 
     In this embodiment, however, the bulb assembly  112  has a low profile relative to that of the first embodiment. In typical commercial embodiments, this low-profile design enables the lighting apparatus to be used safely in places such as closets, crawl spaces, cabinets, dark rooms, under counters, etc. where space is limited. When using conventional lighting apparatus in these places there is the risk of bumping against the bulb, resulting in electric shock/injury to the person and/or damage to the bulb. In addition, inflammable materials are more likely to come into contact with conventional higher-profile light bulbs in tight spaces, and when the lights are left on for a prolonged period of time (and thus overheat) this can pose a fire hazard. 
     The low-profile light-emitting component  118  may be provided for example by one or more CFL tubes in a lateral/transverse arrangement. That is, instead of the CFL tube extending generally longitudinally away from the body (e.g., spirally as in  FIG. 1  or linearly as in  FIG. 9 ), the entire CFL tube is positioned extending laterally across and adjacent the body  120 . In the depicted embodiment, for example, there are three laterally arranged CFL tubes, with the tubes being U-shaped and defining a transverse plane (see  FIG. 6C ) that is generally perpendicular to the longitudinal axis of the lighting apparatus. As can be seen in the figures, this design is very low profile, with the longitudinal dimension of the light-emitting component  118  being smaller (in fact, much smaller) than its transverse dimension. In other embodiments, there are more or fewer laterally arranged CFL tubes, for example, a single tube in a serpentine arrangement winding back and forth closely upon itself and defining the transverse plane. And in yet other embodiments, a reflective surface or coating is provided (e.g., on the front of the bulb assembly body or the back of the tubes) that directs the rearward-emitted light (from the tubes toward the body) forwardly in the desired direction (away from the body). 
     In addition, the bulb assembly  112  may include a diffuser cover  140  made of glass or another generally transparent material. The diffuser cover  140  helps provide some insulating space to keep any nearby inflammable items from directly contacting the CFL tube. The diffuser cover  140  has a small longitudinal dimension (relative to its transverse dimension) so that it too has a low profile. In the depicted embodiment, the diffuser cover  140  is generally disk-shaped with a flat outer surface. In other embodiments the cover is thin but rectangular, polygonal, etc., as may be desired in a given application. 
     Furthermore, the mechanical and electrical connectors can be of the same or a different type as those of the first example embodiment. In the depicted embodiment, for example, the electrical connectors are the same (e.g., a pin-and-head connector received in a slot with enlarged and narrowed portions). The mechanical connectors are similar but somewhat different. In particular, the mechanical connectors include a slotted aperture (as shown) and a tab with a head (not shown). The slotted aperture has a first portion that extends longitudinally and a second portion that extends transversely to lock the head from being withdraw longitudinally. 
     Additionally or alternatively, the mechanical connectors can be provided by magnetic pieces (e.g., magnet and metal pieces) positioned on (e.g., recessed into) the adapter and bulb assembly bodies so that they align and face each other. This helps to keep the adapter and bulb assembly securely connected together even if they reverse-rotate a little bit. In the depicted embodiment, for example, a magnetic mechanical connector  123  is shown on the bulb assembly body  120 . 
       FIG. 7  shows a replaceable LED bulb assembly  212  of a modular lighting apparatus according to a third example embodiment of the present invention. The bulb assembly  212  is similar to that of the first example embodiment in that it includes a light-emitting component  218  attached to a body  220  having first mechanical and electrical connectors. In addition, the bulb assembly  212  is used with an adapter (not shown) similar to that of the first example embodiment, for example, including a screw base and a body with an electronic ballast and with second mechanical and electrical connectors that mate with the first mechanical and electrical connectors. 
     In this embodiment, however, the light-emitting component  218  includes an array of LEDs  282 . The number and lumen ratings of the LEDs  282  are selected based on the illumination desired. The LEDs  282  may be of a conventional type such as the residential and commercial model LR6 LEDs commercially available from CREE (Durham, N.C.). Additionally, the bulb assembly  212  may include a diffuser cover  240  made of glass or another generally transparent material. The diffuser cover  240  preferably has a screw-threaded base that mates with screw-threading on the body  220  so that it can be removed and replaced if needed. Also, the electronic ballast is of a different design and includes a ballast circuit for controlling LEDs. The selection and design of such LED electronic ballast circuits are within the abilities of those of ordinary skill in the art. 
     In typical LED devices, the LEDs are in a parallel arrangement so that all of the LEDs point in the same direction. In this embodiment, however, at least some (and preferably the majority) of the LEDs  282  are mounted on an upright stem  284  in an omni-directional arrangement, that is, with the LEDs pointed in many different directions. For example, in the depicted embodiment a number of the LEDs  282  extend radially outward from the stem  284  in a staggered arrangement so that no adjacent LEDs are parallel and pointed in the same direction. The upright stem  284  extends from the body  220 , houses electrical connections from the LEDs  282  to the first electrical connectors, and is made of a material such as hard plastic or ceramic. 
     In alternative embodiments the LEDs are positioned in other omni-directional arrangements. For example, in one alternative embodiment the stem is generally spherical, hemispherical, aspherical, or hemi-aspherical, and some or all of the LEDs extend radially outward from the spherical stem so that each of these LEDs is pointed in a different direction. 
       FIG. 8  shows a replaceable LED bulb assembly  312  of a modular lighting apparatus according to a fourth example embodiment of the present invention. The bulb assembly  312  is similar to that of the third example embodiment just described. In particular, the replaceable LED bulb assembly  312  includes the primary LED light-emitting component  318   a  and the body  320  of LED bulb assembly  212  of the third example embodiment. However, this embodiment also includes a secondary LED light-emitting component  318   b  mounted to the body  320 . In the depicted embodiment, for example, the secondary LED light-emitting component  318   b  is provided by radially inward and radially outward arranged LEDs  382   b  in an annular diffuser cover  340   b . The diffuser cover  340   b  preferably has a screw-threaded base that mates with screw-threading on the body  320  so that it can be removed and replaced if needed. 
       FIG. 9  shows a modular lighting apparatus  410  according to a fourth example embodiment of the present invention. In this embodiment, the adapter  414  is configured for use with commercially available replaceable CFL bulb assemblies  412 . For example, the CFL bulb assembly  412  may of a twin- or triple-tube type commercially available from Philips Electronics (Andover, Mass.) or General Electric (Fairfield, Conn.). Similarly to the first embodiment, the adapter  414  includes a screw base  428  attached to a body  430  having an electronic ballast  428  and mechanical and electrical connectors  444  and  446 . In this embodiment, however, the adapter body  430  is sized and shaped (i.e., with a generally rectangular opening) to receive a portion of the bulb assembly body  420 . The electrical connectors  446  are provided by apertures that house contacts and receive the pin electrical connectors  426  of the bulb assembly  412 . And the mechanical connectors  444  are provided by notches that releasably receive the spring arm mechanical connectors  424  of the bulb assembly  412 . 
       FIG. 10  shows a modular lighting apparatus  510  according to a fifth example embodiment of the present invention. This lighting apparatus  510  is the same as that of the first embodiment, except for the inclusion of a light-sensing control device  590 . Currently available light-sensing control devices are typically provided in separate units that are installed in-line between the screw socket of the light fixture and the screw base of the light bulb. But this significantly increases the overall height of the composite light assembly, which can be problematic for lighting fixtures with limited space (e.g., enclosed outdoor lanterns). Typical units with light-sensing control devices add one or two or more inches to the overall height of the composite light assembly, with the result that they oftentimes cannot be used due to space limitations. In this embodiment, however, the adapter  514  of the lighting apparatus  510  includes an integral light-sensing control device  590 . 
     In typical commercial embodiments, the light-sensing control  590  is a photocell of the type commercially available from AMERTAC (Saddle River, N.J.) under the WESTEK brand or from LAMSON HOME PRODUCTS (Cleveland, Ohio) under the CARLON brand. As such, the photocell functions to vary the current flow based on the amount of light incident to it, with its resistance increasing in high-light conditions and decreasing in low-light conditions. In addition, the adapter  514  may include an integral sensitivity control  592  of a type known in the art. With the light-sensing control  590  arranged as an integral part of the adapter  514  without increasing the height of the adapter, the overall height of the composite light fixture remains the same while providing the added feature of light control (on at dusk and off at dawn). It should be noted that the light-sensing control device can be integrally provided in any of the embodiments described herein as well as others not expressly disclosed herein. 
     While the invention has been shown and described in preferred forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein. These and other changes can be made without departing from the spirit and scope of the invention as set forth in the following claims.