Patent Application
20110110080
The present disclosure relates generally to a luminaire and, more particularly, to a luminaire for lighting an area such as a parking lot, parking garage, roadway or the like and, even more particularly, to a reflector assembly having a plurality of modular reflectors for directing light from one or more light sources. The disclosure finds particularly useful application when the luminaire employs multiple light sources including, in one embodiment, one or more light emitting diodes (LEDs).
Uncontrolled light can be wasted in lighting areas around the target area to be lighted, and contributes to unwanted “night lighting” which can interfere with the preservation and protection of the nighttime environment and our heritage of dark skies at night. Uncontrolled light also necessitates generation of greater amounts of light to meet the lighting requirements in the target area requiring higher power equipment and energy consumption to provide the target area with the desired amount of light.
The Illuminating Engineering Society of North America (“IESNA”) defines various light distribution patterns for various applications. For example, the IESNA defines Roadway Luminaire Classification Types I-V for luminaires providing roadway and area lighting. The IESNA defines other informal classifications for light distribution patterns provided by roadway and area luminaires as well as light distribution patterns for other applications. These and other light distribution patterns can be obtained by directing light emitted from the one or more light sources in a luminaire. This holds true regardless of light source.
When the light source is one or more LEDs (or other small light sources), it is known to distribute the emitted light by one or more reflectors associated with one or more light sources. One example of a reflector system for distributing light emitted from LEDs is disclosed in U.S. patent application Ser. No. 12/166,536 filed Jul. 2, 2008, the entirety of which is incorporated herein by reference.
Improvements in LED lighting technology have led to the development by Osram Sylvania of an LED having an integral optic that emits a significant portion of the LED light bilaterally and at high angle α (about 60°) from nadir, which is available as the Golden DRAGON® LED with Lens (hereinafter, “bilateral, high angular LED”).
The present disclosure relates to a reflector assembly configured to efficiently distribute light emitted from one or more light source in a luminaire. The reflector assembly is comprised of a plurality of reflector modules each associated with a different set of light sources of the luminaire. The reflector modules can be arranged in different configurations to create different light distributions. By way of example only, the luminaire depicted in
In one embodiment, the present disclosure relates to a reflector assembly for a lighting apparatus, the reflector assembly comprising two or more reflector modules configured for associating with one or more light sources; each reflector module comprising one or more reflectors for being located adjacent to a light source when the reflector module is associated with the one or more light sources, the one or more reflectors configured to reflect light from the adjacent light source.
In another embodiment, the present disclosure relates to a lighting apparatus comprising one or more light sources; a reflector assembly having two or more reflector modules, the reflector modules associated with the one or more light sources; each reflector module comprises one or more reflectors located adjacent to a light source, the one or more reflectors configured to reflect light from the adjacent light source.
The reflector modules of the present disclosure permit the manufacture of different reflector assemblies from reflector modules of the same configuration by orienting one or more of the reflector modules differently. The reflector assemblies of the present disclosure also permits the manufacture of reflector assemblies comprising reflector modules of different configurations. The reflector of the present disclosure thus provides multiple reflector assembly configurations with relatively fewer configurations of reflector modules. The disclosed reflector assemblies thereby lower the number of different parts required to be manufactured or maintained in inventory and decreases the size of parts maintained in inventory thereby lowering costs of inventory and manufacturing while increasing manufacturing flexibility.
The reflector modules 20 depicted in the figures (as best depicted in
The reflector modules 20 of the depicted embodiment comprise lateral reflectors 30 protruding out of the cover plate 22 and extending laterally along the length of the cover plate 22. In one embodiment, the reflector modules 20 are comprised of formed sheet metal and the lateral reflectors 30 are formed of the same sheet as the cover plate 22 as described in copending U.S. application Ser. No. 12/166,536, the entirety of which is incorporated herein by reference. The lateral reflectors 30 can be of any form to create the desired reflecting surfaces necessary for the light distribution sought. In the depicted reflector module 20, the lateral reflectors 30 comprise a first side 32 and a second side 34 with each side 32, 34 being substantially straight and forming an angle at their union. In the depicted embodiment, the first side 32 forms an angle θ1 with the cover plate 22 and the second side 34 forms an angle θ2 with the cover plate 22. In the depicted embodiment, θ1 is 135° and θ2 is 100°. Other angles, curved sides 32, 34 and/or additional surface characteristics are all contemplated as appropriate to create desired light distributions or otherwise.
The reflector modules 20 of the depicted embodiment also comprise overhead reflectors 36, each disposed over a column of light source apertures 24. The depicted reflector modules 20 have overhead reflectors 36 disposed over alternating columns of light source apertures 24 rather than every such column. Fewer or more overhead reflectors 36 are contemplated. For example, an overhead reflector could be located over every column of light source apertures 24, every third column, etc. or over individual light sources. As disclosed in copending U.S. application Ser. No. 12/166,536, the entirety of which is incorporated herein by reference, the overhead reflectors 36 (referenced as “directional members” and given the reference number 122 in copending U.S. application Ser. No. 12/166,536) direct a portion of the light emanating from a light source 16 immediately adjacent thereto laterally. In particular, the light emanating from a light source 16 substantially in the +Z direction is reflected laterally by the overhead reflector 36. The depicted overhead reflectors 30 are configured in substantially a V-shape having a first side 38 and a second side 40 of the V forming a vertex, the outside of which is located over the light source apertures 24, as depicted, to laterally reflect some of the light from the a light source 16 associated with the light source aperture 24. The overhead reflector first and second sides 38, 40 form an angle θ3 with each other which, in the depicted embodiment, is 84°. Other angles, curved sides 38, 40 and/or additional surface characteristics are all contemplated as appropriate to create desired light distributions or otherwise. The overhead reflectors 36 can be of any form to create the desired reflecting surfaces necessary for the light distribution sought.
In one embodiment, the reflector module 20, including all of its elements, are constructed of sheet aluminum. The reflector module 20 may be constructed from a planar sheet that is sufficiently rigid to maintain its shape. A typical planar sheet material is about 5-250 mil (about 0.1-6 mm) thick. The outer surfaces 62 of the cover plate 22 and lateral reflectors 30 are reflective surfaces, in one embodiment, with a finished surface 62 having a reflectance of at least 86%, more typically of at least 95%. In one example, the reflector module 20 is formed of a sheet of aluminum having a MIRO 4 finish, manufactured by Alanod GMBH of Ennepetal, Germany, on the outer surfaces 62. The overhead reflectors 36 may be similarly manufactured with the surfaces of the first and second sides 38, 40 opposing the light sources 16 comprising a finished surface as described above. The finished surfaces could alternatively comprise a specular finish. The surface finishes maximize reflectance and delivery of the lumens generated by the light sources 16 to the desired target area.
The instant disclosure provides the exemplary embodiment reflector module 20 having both lateral reflectors 30 and overhead reflectors 36. A reflector module is contemplated, however, having only one of these two types of reflectors and the term “reflector” when used alone (e.g. without “assembly”, “lateral” or “reflector” associated therewith) shall refer generically to either a lateral reflector 30 or an overhead reflector 36 or other types of reflectors. When the term is used in the plural (i.e. “reflectors”), it may also refer to a combination of overhead or lateral reflectors or other types of reflectors.
The depicted embodiment of the reflector module 20 further comprises first and second lateral walls 42, 44 and first and second end walls 46, 48. The first and second lateral walls 42, 44 extend upward from the cover plate 22 at an angle θ4 therewith. In the depicted embodiment θ4 is 100°, but could be any desired angle to accomplish the desired light distribution and the two angles θ4 could differ. The first end wall 46 forms an angle θ5 with the cover plate 22 and can vary depending on the desire light distribution. In the depicted embodiment, θ5 is 135° to provide the same reflective angle as the second side 34 of the lateral reflectors 30. Similarly, the second end wall 48 forms an angle θ6 with the cover plate 22 that is 100° in the depicted embodiment to conform with the angle between the first side 32 of the lateral reflectors 30. Other angles θ1-θ6 may be used as necessary to accomplish the desire light distribution.
The reflector module 20 also comprises, in the depicted embodiment, an end perimeter flange 50 extending from the first end wall 46 and a lateral perimeter flange 52 extending from the second lateral wall 44. The flanges 50, 52 extend to cover the perimeter of the base 14 otherwise visible to a viewer of the lighting apparatus 10. When the reflector assembly 18 is comprises of four of the depicted reflector modules 20 arranged in the depicted pin-wheeled configuration, the end and lateral perimeter flanges 50, 52 cover the entire perimeter of the reflector assembly 18. Other flanges and flanged arrangements are contemplated to as may be desirable based on the arrangement of reflector modules 20.
The various elements of the reflector module 20 can be integrally formed together or separately. In the depicted embodiment, the cover plate 22, lateral reflectors 30, first and second end walls 46, 48 and end perimeter flange are integrally formed from a single sheet metal by operations that will be apparent to those of ordinary skill in the art. The overhead reflectors 36 are separately formed and mounted to the reflector modules 20 by resting the overhead reflectors 36 in notches 60 defined by the lateral reflectors 30 and, in the depicted embodiment, the first and second end walls 46, 48, allowing the overhead reflectors 36 to lie in each associated notch 60 approximately flush with the top of the lateral reflector 30. In the depicted embodiment, one or more of the lateral reflectors 30 have a tab 54 positioned to reside in a corresponding slot 56 defined by the overhead reflector 30 so that upon placement of the overhead reflector in the notches 60, the tab 54 will reside within the slot 56. The tab 54 is bent along one of the overhead reflector 36 first or second sides 38, 40 to secure the overhead reflector 30 to the reflector module 20. The first and second lateral walls 42, 44 are also secured to the reflector module 20 by a tab and slot system in the depicted embodiment. In particular, end tabs 64 extend from the first and second end walls 46, 48, as depicted, to reside in corresponding end slots 66 in the first and second lateral walls 42, 44 and are bent along the first and second lateral walls 42, 44 to secure them to the reflector module 20. Other manners of securing the overhead reflectors 36 and first and second lateral walls 42, 44 to the reflector module 20 are also contemplated.
Referring to
The reflector modules 20 may also comprise assembly tabs 58, or other structure, extending from the perimeter for connection to an adjacent reflector module 20 or same, similar or different configuration permitting assembly of a plurality of reflector modules 20 into a reflector assembly such as reflector assembly 18 or differently configured reflector assemblies.
The reflector assemblies described in the present disclosure provide several advantages over other devices for directing light from one or more light sources in a luminaire. One advantage is a lessening of different parts in inventory. In particular, the depicted reflector assemblies provide light patterns approximating both IESNA Type II and Type V light distributions from the same reflector modules. Only one part type need be maintained in inventory to provide IESNA Type II and Type V light distributions whereas two parts of different configurations were previously necessary. Furthermore, by lessening the number of different parts in inventory, the number of manufacturing steps, machines and processes are similarly reduced. Additionally, by comprising the reflector assemblies of two or more reflector modules, the size of each reflector module is necessarily smaller than the reflector assembly of which it ultimately becomes a part. The smaller reflector modules permit use of smaller manufacturing equipment and take less space in inventory providing commensurate reductions in costs. The reflector assemblies of the present disclosure are particularly beneficial for use with lighting apparatus having a plurality of light sources, such as the plurality of LEDs depicted in
When employing LEDs such as the depicted light sources 16, the base 14 may be comprised of one or more light boards, and more typically a printed circuit board (“PCB”). The circuitry for controlling and powering the LEDs can also be mounted on the PCB, or remotely. In one suitable embodiment, the LEDs 16 are white LEDs each comprising a gallium nitride (GaN)-based light emitting semiconductor device coupled to a coating containing one or more phosphors. The GaN-based semiconductor device emits light in the blue and/or ultraviolet range, and excites the phosphor coating to produce longer wavelength light. The combined light output approximates a white output. For example, a GaN-based semiconductor device generating blue light can be combined with a yellow phosphor to produce white light. Alternatively, a GaN-based semiconductor device generating ultraviolet light can be combined with red, green, and blue phosphors in a ratio and arrangement that produces white light. In yet another suitable embodiment, colored LEDs are used, such are phosphide-based semiconductor devices emitting red or green light, in which case the LEDs as a group produce light of the corresponding color. In still yet another suitable embodiment, if desired, the LED light board includes red, green, and blue LEDs distributed on the PCB in a selected pattern to produce light of a selected color using a red-green-blue (RGB) color composition arrangement. In this latter exemplary embodiment, the LED light board can be configured to emit a selectable color by selective operation of the red, green, and blue LEDs at selected optical intensities.
When one or more of the light sources 16 comprise an LED, that light source may be a unit consisting of the light-generating diode and an associated optic or the light-generating diode without the optic. When present, the associated optic can be affixed directly to the diode, can be affixed to the substrate in a position next to or in contact with the diode by separate positioning and orientation means, or located or held without the assistance of the substrate or diode. The LED can be of any kind and capacity, though in a preferred embodiment, each LED provides a wide-angle light distribution pattern. A typical LED used in the present disclosure is the wide-angle LED known herein as the bilateral, high angular LED, such as Golden DRAGON® LED manufactured by Osram Sylvania or a Nichia 083B LED. Spacing between these adjacent LED lighting assemblies may be dependent upon the angle α of the bilateral, high angular LED.
While the disclosure makes reference to the details of preferred embodiments of the disclosure, it is to be understood that the disclosure is intended in an illustrative rather than in a limiting sense, as it is contemplated that modifications will readily occur to those skilled in the art, within the spirit of the disclosure and the scope of the appended claims.
