Patent Publication Number: US-9897263-B2

Title: Light panel for a luminaire

Description:
FIELD 
     This application relates generally to luminaires, and, more particularly, for a light panel assembly, such as a door panel, for a luminaire. 
     BACKGROUND 
     A luminaire is generally understood to include one or more light producing subsystems carried by a housing along with power, driving, and/or power distribution devices. In this manner, the luminaire provides a single unit that is easy to install and/or ship. An example of a luminaire is a light fixture, such as a hanging light fixture commonly installed to hang from a ceiling or wall. However, there are many different types of luminaires, and the luminaires discussed herein are to be considered representative of all such devices. 
     In the past, luminaires used to provide relatively high levels of light for relatively large areas, such as outdoors, along driving surfaces such as parking lots, roadways, and tunnels, as well as in industrial areas and warehouses, have often had high-intensity discharge (HID) lamps as the primary light source. HID lamps, in general, are based on passing an electric arc between two spaced apart electrodes within a transparent or translucent arc-tube filled with a gas and/or salts that form intense plasma light when excited by the electric arc. Various examples of such HID lamps include mercury-vapor lamps, metal-halide lamps, ceramic metal-halide lamps, sodium vapor lamps, and xenon lamps. 
     Today, the use of light emitting diode (LED) based lighting systems for luminaires is becoming increasingly commonplace due to their energy efficiency and life span in comparison to other types of light sources, including many common HID lamps. Because of the potential long term energy and cost savings, it is often desired to replace existing installed HID lamps with LED lights. 
     When the HID lamp is disposed within and/or carried by a housing of a luminaire, this change out could be accomplished by replacing the entire HID luminaire with a new LED luminaire. For customers that have very large numbers of luminaires, however, the up-front cost of such a changeover can be extremely high. 
     In order to save costs and re-use existing hardware, it may be possible to retrofit an HID-based luminaire with an LED lamp. Such a retrofit can include removing the HID lamp and associated driving equipment from the luminaire housing and replacing it with an LED lamp assembly and associated driving equipment, thereby re-using the existing luminaire housing and support structures. However, such a change out of the lighting system is often very labor intensive. In addition, the difference in heat production and dissipation mechanisms between an HID-based luminaire and an LED-based luminaire can raise additional difficulties when attempting to retrofit an HID luminaire with an LED lamp assembly. This difficulty arises primarily from the fact that HID lamps generally rely on radiation from the reflector to expel the heat out of the luminaire, whereas LED lamp assemblies often rely on conduction to expel heat from the luminaire. Thus, the difference in heat dissipation mechanisms can also make it more complex to retrofit an LED lamp assembly into the housing of an HID-based luminaire. 
     SUMMARY 
     According to some aspects of the disclosure, a light panel for a luminaire includes a frame, a lamp assembly carried by the frame, a dissipater heat sink carried by the frame, and a heat transfer line that thermally couples the lamp assembly to the dissipater heat sink. The heat transfer line transfers heat generated by the lamp assembly, for example by a light element of the lamp assembly, to the dissipater heat sink by conduction. The dissipater heat sink is exposed to an exterior side of the frame such that heat from the lamp assembly is dissipated to the exterior side of the frame by conduction through the heat transfer line and the dissipater heat sink. 
     According to some aspects of the disclosure, the light panel may be in the form of a door, such as a replacement door, for a luminaire. The door may include a door frame, an LED light board carried by the door frame, a dissipater heat sink carried by the door frame, and a heat transfer line that thermally connects the LED light board to the dissipater heat sink. The dissipater heat sink is exposed to an exterior side of the door frame, and the heat transfer line transfers heat generated by the LED light board to the dissipater heat sink. In this manner, heat from the LED light board is dissipated to the exterior side of the frame by conduction through the heat transfer line and the dissipater heat sink. 
     According to some aspects of the disclosure, a method of retrofitting a luminaire is provided. The luminaire may include a housing defining an interior and an opening into the interior. An existing lamp assembly may be removed from the housing. One or more of the light panel and the replacement door described herein may be coupled to the housing, arranged to cover the opening and project light to an exterior of the housing. The existing lamp assembly may include an HID lamp. 
     The apparatus and method disclosed herein, in some arrangements, may provide an easier and faster way to retrofit a luminaire having an existing lamp assembly, such as an HID lamp assembly, with a new lamp assembly, such as and LED lamp assembly. Additional aspects, arrangements, features, and/or technical effects will become apparent upon detailed inspection of the figures and the detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric view of a luminaire with a light panel operatively installed on a housing according to some aspects of the present disclosure; 
         FIG. 2  is an isometric view of a front side of the light panel of  FIG. 1  in a fully assembled condition; 
         FIG. 3  is an isometric view of a rear side of the light panel in the fully assembled condition; 
         FIG. 4  is an exploded isometric view of the light panel; 
         FIG. 5  is a partially exploded isometric view of the light panel from the rear side; 
         FIG. 6  is a partially exploded isometric view of the light panel from the front side; 
         FIG. 7  is a cross-sectional view of the light panel along the lines  7 - 7  shown in  FIG. 3 ; 
         FIG. 8  is a cross-sectional view of the light panel along the lines  8 - 8  shown in  FIG. 3 ; and 
         FIG. 9  is an enlarged isometric view of a lamp assembly of the light panel, shown in isolation for clarity. 
     
    
    
     DETAILED DESCRIPTION 
     Before describing the specific examples of the drawings, some general aspects, arrangements, and features of the disclosed luminary light panel assembly, and/or luminaires are provided. 
     In some arrangements, a light panel for a luminaire includes a frame having an exterior side and an interior side opposite the exterior side. A lamp assembly is carried by the frame. The lamp assembly may include a light element arranged to project light toward the exterior side of the frame. A dissipater heat sink is carried by the frame. The dissipater heat sink may be spaced apart from the lamp assembly. The dissipater heat sink is exposed to the exterior side of the frame. At least one heat transfer line thermally couples the lamp assembly to the dissipater heat sink. The heat transfer line transfers heat generated by the light element to the dissipater heat sink by conduction. In this manner, heat from the light element is dissipated to the exterior side of the frame by conduction through the heat transfer line and the dissipater heat sink. 
     The heat transfer line may have the form of an elongate member made of metal or other highly thermally conductive material. For example, the heat transfer line may be a wire, a rod, a tube, and/or a pipe. The heat transfer line may be made of aluminum. 
     The lamp assembly may include an LED light board. The LED light board may have a circuit board. The light element may include a light emitting diode (LED) coupled to the circuit board. A secondary optic may be arranged to focus light from the LED toward the exterior side of the frame. The LED light board may be disposed on the interior side of the frame. 
     The dissipater heat sink may include a first section and a second section coupled to the first section. A first portion of the heat transfer line may be sandwiched between the first section and the second section. The dissipater heat sink may include cooling fins. The cooling fins may be disposed on the exterior side of the frame. 
     The frame may include a mount to attach the frame to a luminaire housing. The mount may be a hinge, and the frame may form a door frame. Thus, the light panel may form a replacement door or other replacement panel for a luminaire. 
     An accumulator heat sink optionally may be coupled to the lamp assembly so as to collect heat from the light element. The accumulator heat sink may be spaced apart from the dissipater heat sink. The heat transfer line may be thermally coupled to the accumulator sink and may be thermally coupled to the dissipater heat sink. The accumulator heat sink may have a first section and a second section coupled to the first section. A second portion of the heat transfer line may be sandwiched between the first section and the second section of the accumulator heat sink. A bracket may be provided to hold the accumulator heat sink against the lamp assembly and/or to hold the lamp assembly in a fixed position relative to the frame, for example, via a coupling to the accumulator heat sink. Thus, the bracket can help maintain the lamp assembly in a preferred fixed position to emit light outwardly from the light panel. 
     The frame may include an outer frame and an inner frame coupled to the outer frame. The outer frame, and optionally the inner frame, may have a first opening. A window may be captured between the outer frame and the inner frame to cover the first opening. The light element may shine through the window and the first opening. 
     The outer frame, and optionally the inner frame, may have a second opening. The dissipater heat sink may extend through the second opening. The dissipater heat sink may include a dissipater cap connected to heat fins. The dissipater cap may be captured between the inner frame and the outer frame. The heat fins may be disposed on the exterior side of the frame. 
     The frame may be formed of a first metal, such as a highly wear-resistant metal, and the dissipater heat sink, the accumulator heat sink, and/or the heat transfer tubes may be formed of a second metal, such as a highly heat conductive metal. For example, the first metal may be stainless steel and/or the second metal may be aluminum. However, other metals and/or other non-metallic materials could be used. A sealing element may be provided that electrically isolates the dissipater heat sink from the frame, which may prevent or reduce undesirable electro-chemical reactions therebetween, such as galvanic reactions. 
     In some arrangements, a replacement door for a luminaire, includes a door frame having an interior side and an exterior side and a hinge for mounting to a housing of the luminaire, an LED light board carried by the door frame and disposed on the interior side of the door frame, a dissipater heat sink carried by the door frame, the LED light board arranged to project light toward the exterior side of the door frame, and a heat transfer line thermally coupling the LED light board to the dissipater heat sink. The dissipater heat sink is spaced apart from the LED light board and exposed to the exterior side of the door frame. The heat transfer line transfers heat generated by the LED light board to the dissipater heat sink. In this manner, heat from the LED light board is dissipated to the exterior side of the frame by conduction through the heat transfer line and the dissipater heat sink. 
     An accumulator heat sink may be coupled to a back side of the LED light board and arranged to collect heat generated by LEDs on the LED light board via conduction. The accumulator heat sink may be spaced apart from the dissipater heat sink. A first end of the heat transfer line may be coupled to the accumulator sink, and a second end of the heat transfer line may be coupled to the dissipater heat sink. 
     An electric power driver may be operatively coupled to the LED light board to power the LED light board. The power driver may be carried by the door frame, either attached directly to the frame or indirectly to the frame via one or more intermediate structures, and disposed on the interior side of the door frame. 
     The dissipater heat sink may have heat fins disposed on an exterior side of the door frame and a dissipater cap. The heat transfer line may be attached to the dissipater cap. 
     The door frame may have a first opening and a window covering the first opening. The LED light board may project light through the window. The window may include or form a diffuser and/or a lens. The window may form a tertiary optic. 
     While specific exemplary forms are illustrated and described herein, is to be understood that any of the various aspects, arrangements, and/or features disclosed herein may be combined with any one or more of the other aspects, arrangements, and/or features disclosed herein. 
     Turning now to the exemplary arrangements of the drawings,  FIG. 1  illustrates a luminaire  10  that includes a light panel  12  exemplifying some aspects of the present disclosure and a housing  14  that carries the light panel  12 . The housing  14  defines interior space (not visible) suitable for receiving various components of the light panel  12 , such as a power driver, reflector, and light element. The housing  14  is also suitable for mounting to a support surface, such as a wall, ceiling, hanger, etc., and includes an opening  16  into the interior space. In this arrangement, the housing  14  is in the form of generally rectangular metal box, made of stainless steel for example; however, the housing  14  may take other forms suitable for carrying and receiving the light panel  12  and mounting the light panel  12  to a support surface. 
     The light panel  12  is mounted to the housing  14  by one or more couplers  18 . The couplers  18  may include, for example, hinges, latches, slots, straps, fasteners, hangers, or other couplings, and/or various combinations thereof. Preferably, the couplers  18  releasably couple the light panel  12  to the housing  14  so as to cover the opening  16  in an operative position. The light panel  12  may partially or completely seal the opening  16  against ingress of dirt and/or water through the opening  16  into the interior of the housing. 
     The light panel  12  may have different shapes, sizes, and/or forms depending on the specific requirements of a given luminaire. In the present example, the light panel  12  is in the form of a door for the luminaire  10  and includes one or more hinges  20  that pivotably couple to the housing  14  such that the light panel  12  can be pivoted about the hinges  20  to open and/or close the opening  16 . Further, the couplers  18  in this example include cam latches that releasably latch the light panel in a closed position covering the opening  16 . However, in other forms, the light panel  12  may simply form a sidewall, or portion of a sidewall of a luminaire or some other type of panel that is part of a luminaire. 
     The light panel  12  in the form of a door may be, for example, a replacement door for the luminaire  10 . For example, the luminaire  10  may have originally carried and contained an HID lamp assembly, including an HID lamp, an electric power driver and control electronics, and a reflector within the housing  14 . The HID lamp assembly may be removed from the housing  14 , and replaced with the light panel  12  by connecting the hinges  20  to the housing  14 . Appropriate electrical connections would also be made to provide appropriate power to the light panel  12 . The light panel  12  can then be secured in the closed position over the opening  16  by latching the couplers  18 . In this manner, the light panel  12 , when including an LED lighting system as described hereinafter, provides for a relatively simple and fast way to convert an HID-based luminaire into an LED-based luminaire. 
       FIGS. 2-8  show the light panel  12  separately from remaining portions of the luminaire  10  in various views as described previously for improved visibility. The light panel  12  includes a frame  22 , a lamp assembly  24  carried by the frame  22 , a dissipater heat sink  26  carried by the frame  20 , and at least one heat transfer line  28  that thermally couples the lamp assembly  24  to the dissipater heat sink  26 . The lamp assembly  22  includes one or more light elements  30  (see  FIG. 9 ) arranged to project light outwardly toward an exterior side  32  of the frame  22  and from the luminaire  10  when operatively coupled thereto. The heat transfer line  28  transfers heat generated by the lamp assembly  24  to the dissipater heat sink  26 , which is exposed to the outside environment on the exterior side  32  of the frame. In this manner, heat from the light element(s) is dissipated to the outside environment on the exterior side of the frame  22  by conduction through the heat transfer line(s)  28  and the dissipater heat sink  26 . 
     The frame  22  itself has the exterior side  32  and an interior side  34 . In this arrangement, the frame  22  has the shape of a generally flat plate such that the exterior side  32  and the interior side  34  are opposite sides of the generally flat plate. When the light panel  12  is operatively mounted on the housing  14  as illustrated in  FIG. 1 , the interior side  34  faces the interior of the housing  14 , and the exterior side  32  faces outwardly from the housing. Thus, the exterior side  32 , if not covered by another object, forms an exterior surface of the luminary  10  when operatively mounted on the housing  14 . However, the frame  22  is not limited to a generally flat plate, but may have other shapes as appropriate to cover an opening in the housing  14  of a luminaire with an exterior side and an interior side and to conform to the specific shape of the housing  14 . 
     As best seen in  FIG. 9 , the lamp assembly  22  in this example is an LED lamp assembly including an LED light board  36 . The LED light board  36  includes a circuit board  38 , and the light elements  30  are LEDs (light emitting diodes) operatively disposed on the circuit board  38  to produce light. The LED light board  36  may include primary optics covering the LEDS, as is common for LED light boards. The lamp assembly  22  optionally includes one or more secondary optics  40  disposed over the primary optics for providing additional focusing and/or directional control of the light emitted by the LEDs. The secondary optic  40  may have, for example, a collimator lens and/or a light pipe that provides a selected direction and/or focus of the light outward toward a desired illumination surface, such as a parking lot, street, floor, or working area. Optionally, the secondary optics  40  may be grouped in one or more optic panels  42 , wherein each optic panel  42  includes one or more of the secondary optics  40 . One exemplary secondary optic  40  that may be suitable for use in some circumstances is described in co-pending U.S. patent application Ser. No. 14/850,290, filed on Sep. 10, 2015, the complete disclosure of which is incorporated by reference herein. However, other secondary optics  40  may also be used if desired. Further, other types of lamp assemblies may be used, which may include other types of lamps, and the disclosure is not necessarily limited to LED lamps or LED lighting systems. 
     Optionally, a driver box  44  is also carried by the frame  22  so as to form a unitary part of the light panel  12 . The driver box  44  includes a driver housing and one or more electrical power drivers (not visible) disposed inside the driver housing operatively arranged to control and/or provide electrical power to light the light elements  30  on the circuit board  38 . The driver box  44  may be coupled directly to the frame  22  or indirectly to the frame  22 . In the illustrated example, the driver box  44  is coupled indirectly to the frame  22 . The driver box is attached to a housing  46 , which is in turn attached to the frame  22 . However, other coupling arrangements are also contemplated, depending on the specific space and shape requirements of a given luminaire. 
     In the present arrangement, the entire lamp assembly  24  is disposed on the interior side of the frame  22 , and the light elements  30  direct light through a first opening  48  in the frame so that the light shines through the frame  22  to the exterior side  32 . Optionally, a window  50  covers the first opening  48  to allow the light to travel through the frame  22  while protecting the lamp assembly  24  from the outside elements. The window  50  may form a tertiary optic, such as a diffuser, lens, or collimator, or may simply provide a transparent barrier. Preferably, a seal  52  disposed between the window  50  and the frame  22  extends completely around the first opening  48  to keep dirt and/or water from passing through the first opening  48  from the exterior side  32  to the interior side  34 . 
     The dissipater heat sink  26  is spaced apart from the lamp assembly  24  so as not to contact the lamp assembly  24  and thereby form a thermal barrier in the form of an air gap between the lamp assembly  24  and the dissipater heat sink  26 . The dissipater heat sink  26  is exposed directly to the atmosphere on the exterior side  32  of the frame  22 . Thus, heat radiated from the dissipater heat sink  26  is dissipated to the environment on the exterior side  32  of the frame  22  such that, when the light panel  12  is operatively mounted to the housing  14 , the heat is dissipated to the external environment surrounding the luminaire  10 . In the illustrated arrangement, the dissipater heat sink  26  includes a set of heat fins  54  disposed on the exterior side  32  of the frame  22 . The heat fins  54  are in the form of a series of parallel, spaced apart fins, which may be made of a highly heat conductive metal, such as aluminum. The dissipater heat sink  26  also includes a dissipater cap  56  that couples the dissipater to the heat transfer lines  28 . The dissipater cap  56  is made of a thermally conductive material, such as aluminum, so as to thermally couple the heat transfer lines  28  to the heat fins  54 . The dissipater cap  56  includes a first section  56   a  and a second section  56   b  coupled to the first section. The first and second sections  56   a ,  56   b  sandwich, such as by clamping, a portion of the heat transfer lines  28  therebetween. In the exemplary arrangement, the first section  56   a  forms an upper plate and the second section  56   b  forms a lower plate that are attached to the heat fins  54 , for example, by one or more screws or other fasteners. Preferably, the upper and lower sections  56   a  and  56   b  form recesses that receive and clamp the heat transfer lines  28  therebetween, thereby physically connecting the heat transfer lines  28  to the dissipater heat sink  26 . In this arrangement, each of the first and second sections  56   a  and  56   b  is generally flat with opposing half-cylindrical recesses that receive ends of heat transfer lines  28 . However, the dissipater heat sink  26  need not be limited to the exact form of this example. For example, in some arrangements the dissipater cap  56  may have a different shape and/or may have different connection mechanisms for coupling to the heat transfer lines  28 . Or, the dissipater cap  56  in some arrangements may be omitted altogether, and the heat transfer lines  28  could connect directly to the heat fins  54 . Further, the heat fins  54  may have different shapes and/or sizes and/or arrangements. The main point is that the dissipater heat sink  26  have a form suitable for thermally coupling to the heat transfer lines  28  and dissipating by radiation heat conducted thereto to the exterior side of the frame  22 , and thus away from the interior of the luminaire  10  when assembled thereon. 
     The heat transfer lines  28  thermally connect the lamp assembly  24  to the dissipater heat sink  26  so as to transfer by conduction heat generated by the light elements  30  of the lamp assembly  24  to the dissipater heat sink  26 . In this example, each heat transfer line  28  is an elongate tube made of a heat conductive material, such as aluminum, and preferably having opposite first and second ends  58   a  and  58   b . The first end  58   a  of each heat transfer line  28  is thermally coupled with the lamp assembly  24  to collect heat generated by the light elements  30 . The second end  58   b  of each heat transfer line  28  is thermally coupled with the dissipater heat sink  26 , for example by being clamped between the first and second sections  56   a  and  56   b  (e.g., upper and lower plates) as described previously herein. However, the heat transfer lines may take other elongate forms suitable for thermally connecting the dissipater heat sink  26  with the lamp assembly  24  to conduct the generated heat to the dissipater heat sink  26 , such as rods, wires, ribbons, bars, etc. 
     The first end  58   a  of each heat transfer line  28  may be thermally coupled with the lamp assembly  24  either directly or indirectly. In the illustrated example, the first ends  58   a  of the heat transfer lines  28  are indirectly thermally coupled with the lamp assembly  24  by an accumulator heat sink  60 . The accumulator heat sink  60  is attached to a rear side of the lamp assembly  24  and is made of a heat conductive metal, such as aluminum, so as to collect the heat from the lamp assembly  24  by conduction. The accumulator heat sink  60  is connected to the first ends  58   a  of the heat transfer lines  28 . Preferably, the accumulator heat sink  60  is thermally isolated from the dissipater heat sink  26 , such by being spaced apart from each other with an air gap in between. The accumulator heat sink  60  in the illustrated example is generally similar to the dissipater cap  56 , having a first section  60   a  coupled to a second section  60   b  that sandwich a portion of the heat transfer lines  28  therebetween. Also similar to the dissipater cap  56 , the first section  60   a  may form of an upper plate, and the second section  60   b  may form a lower plate that, together, clamp the heat transfer lines  28  therebetween. Each of the first and second sections  60   a  and  60   b  is generally flat with opposing half-cylindrical recesses that receive the first ends  58   a  of the heat transfer lines  28  therein. Like the dissipater cap  56 , the accumulator heat sink  60  is not necessarily limited to this shape and form, and may take other shapes and forms suitable for thermally connecting the lamp assembly  24  to the heat transfer lines  28 . In other arrangements, the first ends  58   a  of the heat transfer lines  28  may be directly thermally coupled with the lamp assembly  24 , for example by having a heat transfer line  28  attached directly to or close enough to a light element  30  of the lamp assembly  24  so as to draw the heat directly from the light element  30 . 
     Preferably, although not necessarily, the light panel  12  provides all of the major components necessary for the light producing functions of the luminaire  10  together as a single unit. This provides the benefit of allowing the light panel  12  to be quickly and easily installed in the housing  14  of the luminaire  10 , either as original equipment or as retrofitted replacement equipment. Following are some additional details of the light panel  12  that may optionally be provided in order to provide additional benefits and/or useful features. 
     As best seen in  FIGS. 3-5 , on the rear side of the light panel  12 , which corresponds with the interior side  34  of the frame  22 , the housing  46  may be attached to the interior side  34  of the frame  22 . The housing  46  substantially covers the rear sides of the dissipater heat sink  26  and the accumulator heat sink  60  and the heat transfer lines  28 . The housing  46  optionally includes one or more openings  62 , which may allow heat from the lamp assembly  24 , the dissipater cap  56 , the accumulator heat sink  60 , and/or the heat transfer lines  28  to escape by radiation and thereby provide additional cooling for the light panel  12 . The driver box  44  is attached to the housing  46 , for example, with screws or bolts. Thus, when assembled, the rear side of the light panel  12  provides a relatively clean shape and form that is easy to handle and install as a unit, for example, into the housing  14  of the luminaire  10 . 
     As best seen in  FIGS. 4 and 5 , one or more brackets  64  may be provided that hold the accumulator heat sink  60  against the rear of the lamp assembly  24 . The brackets  64  can help maintain a continuous and/or continual contact to enable conductive heat transfer from the lamp assembly  24  to the accumulator heat sink  60 . The brackets  64  can help maintain the lamp assembly  24  in a selected position relative to the frame  22  with the light elements  30  on the front side of the lamp assembly  24  arranged to project light through the first opening  48  and the window  50  toward the exterior side  32  of the frame  22 . In some arrangements, other mechanisms, such as screws or welds, may be additionally or alternatively provided to fasten the accumulator heat sink  60  against the lamp assembly  24 . Each bracket  64  is attached to the frame  22  at one location and is attached to the accumulator heat sink  60  at another location so as to clamp and/or hold the accumulator heat sink  60  against the lamp assembly  24 , such as against the rear side of the circuit board  38 , and in a fixed position relative to the frame  22 . As best seen in  FIG. 7 , the lamp assembly  24  may be attached to the front side of the accumulator heat sink  60 , for example, with screws, clips, welds, or other appropriate fasteners. Thus, in this example, the brackets  64  provide the primary mechanism for holding the accumulator heat sink  60  and the lamp assembly  24  in the operative position with the light elements  30  shining outwardly through the window  50 . In the illustrated example, there are two brackets  64  disposed on opposite sides of the accumulator heat sink  60 ; however, more or fewer and different arrangements of such brackets are also contemplated. 
     The frame  22  may also include one or more optional features that can provide additional technical benefits. For example, in the illustrated example as best seen in  FIGS. 4 and 6-8 , the frame  22  is formed of two sections, an outer frame  66  and an inner frame  68 . The outer frame  66  has a plate section that forms the surface disposed on the exterior side  32  of the frame and faces the exterior of the luminaire  10  when operatively mounted. The inner frame  68  has a plate section that is generally the same size and shape as the plate section of the outer frame  22   a  and forms the surface that is disposed on the interior side  34  of the frame  22 . Optionally, the inner frame  68  has a slightly smaller outer periphery than the outer frame  66  and includes a peripheral sidewall  68   a  extending around the outer periphery of the plate section. When the inner frame  68  is operatively coupled to the outer frame  66 , the plate sections face and oppose one another substantially parallel with each other, and the peripheral sidewall  68   a  acts as a spacer to maintain a gap between the opposing plate sections. Both the inner frame  68  and the outer frame  66  have congruent first openings  48   a  and  48   b  that together define the first opening  48  through the frame  22 . Further the frame  22  has a second opening  70 , defined by congruent second openings  70   a  and  70   b  in both the inner and outer frame  68  and  66 , through which the dissipater cap  56  extends to couple to the heat fins  54 . The window  50  is clamped between the inner frame  68  and the outer frame  66  across the first opening  48 . The dissipater cap  56  is clamped between the inner frame  68  and the outer frame  66  across the second opening  70 . 
     The seal  52  may be provided that extends around the outer periphery of the window  50  and forms a peripheral seal between the window and each of the inner frame  68  and the outer frame  66 , thereby preferably forming a water tight peripheral barrier to prevent ingress of water and dirt through the first opening  48  around the window  50 . A second seal  72  may be provided that extends around the outer periphery of the dissipater cap  56  and forms a peripheral seal between the dissipater cap  56  and each of the inner frame  68  and the outer frame  66 , thereby preferably forming a water tight peripheral barrier to prevent ingress of water and dirt through the second opening  70  around the dissipater cap  56 . In addition, the second seal  72  may be made of an electrical insulator, such as rubber or other similarly electrically insulating material, so as to electrically isolate the dissipater cap  56 , which may be made of aluminum, from the frame  22 , which may be made of stainless steel, in order to prevent a galvanic reaction between the to different metals. As can be seen in  FIGS. 7 and 8 , each of the first seal  52  and the second seal  72  preferably has a C-shaped cross-section that forms a groove to receive the peripheral edge of the window  50  or dissipater cap  56 , respectively. 
     The exact arrangement and shape of the inner frame  68  may be varied, however, and need not be limited to the illustrated example. In other arrangements for example, the inner frame  68  may not include the first opening  48   b  and/or second opening  70   b , but rather may have a different shape that is arranged to hold the window  50  and/or the dissipater heat sink  26  in a desired position. Still further, in other arrangements, the frame  22  may have more, fewer, and/or different shaped and/or sized components, for example, being formed of a single piece and using different types of connectors to carry the lamp assembly  24 , dissipater heat sink  26  and the heat transfer pipes  28 , as well as any other components that are provided. 
     This detailed description is to be construed as examples only and does not describe every possible embodiment, as describing every possible embodiment would be impractical, if not impossible. One could implement numerous alternate embodiments, using either current technology or technology developed after the filing date of this application.