Patent Publication Number: US-9410688-B1

Title: Heat dissipating assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention is directed to a heat dissipation assembly for an illumination structure of the type which includes at least one LED and a driver operatively connected to the LED. A compartment structure, including an interior chamber having heat insulating fluid disposed therein, is disposed in predetermined adjacent and/or aligned relation to the LED and the driver assembly and/or other heat generating components to effectively restrict the exposure of the LED to heat. 
     2. Description of the Related Art 
     Various types of illumination assemblies which incorporate light emitting diodes (LED) as the light generating component have become increasingly popular in recent years. Such an increase in popularity is due, at least in part, to their overall efficiency as well as the ability to define various lighting arrays readily adaptable to numerous practical installations or applications. 
     Accordingly, LEDs are known for use in high power applications such as spotlights, automotive headlights, etc. However, due to their recognized versatility LEDs are also utilized extensively in various types of luminaires and/or like fixtures installed in conventional domestic and commercial environments. Such applications allow for the illumination of a given area in an efficient and variably decorative manner in that associated light fixtures may take the form of standard or customized lighting arrays, wall or ceiling mounted fixtures, inset lighting, etc. Further, LEDs provide increased energy efficiency and effective illumination output from the various types of light fixtures installed, while reducing maintenance costs associated therewith. 
     Therefore, the use of illumination assemblies incorporating collective LED arrays offer significant advantages in terms of increased lighting and efficiency of operation. However, certain disadvantages and problems associated with the use of LED based illumination assemblies are commonly recognized. More specifically, a primary concern with the structuring and use of LED illumination assemblies is the management or dissipation of excessive heat generated by the LED array. More specifically, the light intensity generated by an LED light source is generally a proportional function of its operational temperature. As such, LED illumination assemblies tend to generate a significant amount of heat during their operation, which in turn may derogatorily affect the light generated by the LED array as well as reduce the reliability and operational life thereof. Accordingly, the operable life of many LED based illumination assemblies may be significantly reduced due to premature failure of one or more light emitting diodes associated with a light fixture or other device. 
     Therefore, it is commonly recognized in the lighting industry that heat management and more specifically, heat dissipation is a critical structural and operational consideration in the manufacture, use, installation and overall viability of illumination assemblies incorporating light emitting diodes as the primary or exclusive light generating structure. Known attempts to overcome the problems associated with the generation of excessive heat involve the creation of diverse heat dissipating structures. By way of example, printed circuit boards have been disposed in a multi-layered or stacked array in attempt to transfer heat away from the LED array. Alternatively, one or more printed circuit boards associated with the operational control of the LED light generating structures include a metal core disposed and structured to further effect heat dissipation. 
     Other known or conventionally proposed solutions to the heat management problem include the utilization of a heat absorber including a heat conductive resin disposed in communicating relation with the circuitry of the LED array. Also, heat absorbing structures may be utilized which have a large physical configuration such as, but not limited to, a multi-finned structure providing a conductive path of heat transfer towards an area of dissipation. However, many known attempts do not effectively accomplish optimal heat transfer, resulting in lower operational performance and a reduced operational life as generally set forth above. 
     Accordingly, there is a long recognized need in the lighting industry for an efficient and practical heat dissipation assembly preferably of the type which may be easily included in the structure of a light fixture. Such a proposed assembly would allow the light fixture to assume any number of design configurations best suited to a specific application which is structured to effectively dissipate heat. As such, an LED based light assembly would be capable of an optimal level of light generation, while at the same time enjoying an extended operational life. Also, such an improved proposed light fixture should also include structural components which serve to effectively isolate or segregate the conductive material components associated with heat dissipation from direct contact with any type of electrical conductor. 
     Therefore, the proposed light fixture assembly would accomplish effective heat dissipation from a LED based illumination assembly, while at the same time assuring operational safety. Further, the proposed light fixture would be capable of sufficient structural and operational versatility to permit the light fixture to assume any of a variety of utilitarian and aesthetic configurations. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an assembly which is structured to dissipate heat from an illumination structure of the type which includes one or more LEDs defining an illumination source of the illumination structure. In addition, the illumination structure includes a driver assembly operatively connected to the one or more LEDs and facilitating its operation. As used herein, the term “driver assembly” or “driver” is to be broadly interpreted and may include an electrical circuit or other electronic component(s) used to control another circuit or other electronic component. In the present invention the driver assembly is used to operatively control the one or more LEDs. 
     Additional structural and operative features of the illumination structure and the heat dissipation capabilities associated therewith include a primary heat sink formed of heat conductive material and disposed in heat transferring relation to other heat generating portions of the illumination structure. Also, a mounting structure or “mount” is formed of heat conductive material and is disposed in connected and/or at least partially supporting relation to the driver assembly. Further, in at least one preferred embodiment the mount defines a secondary or supplementary heat sink and is disposed in heat transferring relation between the driver assembly and the primary heat sink. As a result, the mount and the primary heat sink collectively and at least partially define a path of heat flow from the driver assembly and/or other heat generating components of the light structure, to an area where the heat is safely or preferably dissipated from the light structure. Therefore, the present invention comprises a cooperative and collective structuring and positioning of the mount and primary heat sink to define the aforementioned flow path of heat from the driver assembly to an area for heat dissipation, such as an area or space located on the exterior of the light structure. 
     Additional structural and operative features of the heat dissipating assembly of the present invention include the provision of a compartment structure. Moreover, the compartment structure includes an interior chamber which is at least partially hollow or open, at least to the extent of containing air or other heat insulating fluid therein. Further, the compartment structure, at least generally, and the interior chamber, more specifically, are disposed relative to the one or more LEDs to effectively insulate the one or more LEDs from heat. As such, the compartment structure and/or interior chamber are disposed sufficiently adjacent and/or in predetermined aligned relation with the one or more LEDs so as to restrict heat, which may be generated by other components of the light structure, from reaching or otherwise affecting the one or more LEDs. 
     As explained in greater detail hereinafter, one or more preferred embodiments of the heat dissipating assembly comprise the chamber and heat insulating fluid disposed therein, being located in a predetermined alignment with the at least one LED. As such, the heat insulating fluid disposed within the interior chamber of the compartment structure will at least partially restrict the LED(s) from being exposed to heat generated by, at least the driver assembly and possibly other heat generating components of the illumination structure. Moreover, the compartment structure and interior chamber may be sufficiently adjacent and/or substantially aligned with both the driver assembly and the at least one LED. As a result, the heat generated by at least the driver assembly will be restricted from passing through the heat insulating fluid within the chamber to the LED. Such a concurrent alignment or adjacent positioning of the chamber may be accomplished by disposing the compartment structure and/or the interior chamber thereof in an at least partially “sandwiched” relation, substantially between the mount and the primary heat sink. 
     It is emphasized that the compartment structure and its chamber may be independently structured, disposed and/or positioned in heat insulating relation to the one or more LEDs. However, the compartment structure and interior chamber may also be disposed on or structurally associated with various components of the illumination structure. By way of example, the mount connected to and/or otherwise associated with the driver assembly, such as by being in heat transferring relation thereto, can be configured to include and/or at least partially define the compartment structure as a part thereof. Somewhat similarly, the compartment structure can be more closely associated with or otherwise connected to and or formed at least partially on the primary heat sink. Further, the mount and primary heat sink can be cooperatively disposed, dimensioned and configured to facilitate the positioning of the compartment structure and interior chamber therebetween. In any of the above noted structural embodiments, at least the interior chamber of the compartment structure is disposed in sufficiently adjacent relation to the one or more LEDs to restrict the passage of heat through the heat insulating fluid disposed within the chamber. It is further noted that the heat being dissipated or directed away from the one or more LEDs may be primarily or partially generated by the driver assembly and/or other components of the illumination structure. 
     Accordingly, one or more preferred embodiments of the heat dissipating assembly of the present invention include a strategic location of the interior chamber of the compartment structure, relative to the primary heat sink and secondary heat sink (heat conductive material of the mount). Such cooperative positioning and structuring of the compartment structure, mount and primary heat sink facilitate the aforementioned flow path of heat from at least the driver assembly into and along the heat conductive material of the mount, into and along the primary heat sink to an area, preferably exteriorly of the illumination structure, where the heat can be safely dissipated. 
     Is also emphasized that the dimensions, configurations and other structural features of the mount, compartment structure and associated interior chamber, as well as the primary heat sink can vary based on the overall size and configuration of the illumination structure and/or its application, environment of use, etc. Further, the aforementioned heat insulating fluid disposed within the interior chamber may be air or other fluid which restricts the passage of heat there through thereby accomplishing the intended heat insulation of the correspondingly disposed one or more LEDs. 
     These and other objects, features and advantages of the present invention will become clearer when the drawings as well as the detailed description are taken into consideration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the nature of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which: 
         FIG. 1  is a bottom perspective view of a light fixture including an LED illumination source of the type with which a heat dissipation assembly of the present invention may be used. 
         FIG. 2  is a bottom perspective view in partial cutaway showing structural details of the embodiment of  FIG. 1 . 
         FIG. 3  is an exploded perspective view of the various operative features and structural components associated with the light fixture as represented in  FIGS. 1 and 2 . 
         FIG. 4  is a schematic representation of the heat dissipating assembly of the present invention structurally and operatively adapted to be used in combination with a light fixture, including an LED illumination source, of the type represented in  FIGS. 1-3 . 
     
    
    
     Like reference numerals refer to like parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in the accompanying drawings, the present invention is directed to a heat dissipating assembly, generally indicated as  100 , as schematically represented in  FIG. 4 . However, for the purpose of clarity and by way of example,  FIGS. 1-3  disclose a representative light fixture generally indicated as  10 , with which the heat dissipating assembly  100  may be used. It is emphasized that the heat dissipating assembly  100  may vary in structure and operation from the light fixture  10  of  FIGS. 1-3 , as pointed out in greater detail hereinafter, without departing from the intended spirit and scope of the present invention. 
     Accordingly, the light fixture  10  is of the type which may be installed in any of a variety of commercial, domestic or other sites and is decorative as well as functional to effectively illuminate a given area or space in the vicinity of the installed location. More specifically, the light fixture  10  includes an illumination structure generally indicated as  12  comprising one or more light emitting diodes (LED)  14  connected to electrical control circuitry generally indicated as  16 . The control circuitry  16  may comprise a printed circuit structure  16 ′ or printed circuit board having the various electrical or circuitry components integrated therein. As also set forth in greater detail hereinafter, the heat dissipating assembly  100  as represented in  FIG. 4  includes control circuitry, which includes or is defined by a driver assembly. Again, for purposes of clarity the driver assembly and/or control circuitry is represented in  FIG. 4  as  116 . 
     In addition, the light fixture  10  includes a mounting assembly or “mount” generally indicated as  18 , which may or may not be in the form of a plate or disk-like configuration as also represented. It is emphasized that the specific structural configuration and dimension of the mount or mounting assembly  18  may vary from that other than the represented plate or disk like shape. When assembled, the mount  18  is connected in supporting relation to the illumination structure  12  such that the control circuitry and/or driver assembly  16 , is disposed in direct confronting and heat transferring engagement with a corresponding portion of the mount  18  as clearly represented in  FIG. 3 , as well as the schematic representation of the heat dissipating assembly  100  represented in  FIG. 4 . Additional structural features of the mount or mounting assembly  18  include its formation from a heat conductive material having sufficient heat conductive properties to act as a heat sink. As such, the mount  18  may be formed from a metallic or other material which facilitates the transfer of heat. Such confronting engagement between the illumination structure  12  and the mounting assembly  18  serves to adequately support and position the illumination structure  12  in its intended orientation substantially co-axial to the mounting assembly  18  and also facilitates the transfer and dissipation of heat from the illumination structure  12  to and throughout the mounting assembly  18 . As again emphasized and explained in greater detail hereinafter with primary reference to  FIG. 4 , the structural features of the heat dissipating assembly  100  may differ from that disclosed in the representative light fixture  10 . 
     In order to enhance and render most efficient, the heat dissipating capabilities of the light fixture  10 , a primary heat sink is included in the form of a cover structure generally indicated as  20 . As represented in both the light fixture  10  of  FIGS. 1-3  and the heat dissipating assembly  100  as represented in  FIG. 4 , the primary heat sink  20  is connected directly to the mount mounting assembly  18  and is therefore in heat transferring relation therewith. More specifically, the primary heat sink or cover structure  20  is also formed of a heat conductive material demonstrating sufficient heat conductive properties to be capable of heat transfer throughout its structure. Therefore, efficient heat transfer from the illumination structure  12  and control circuitry or driver assembly  16  to the mounting assembly  18  and therefrom to the cover structure  20  is facilitated by the continuous confronting engagement of correspondingly positioned surfaces  18 ′ and  20 ′ respectively. 
     Heat dissipation is further facilitated by the structuring of the cover structure  20  to have an overall larger dimension than that of the mounting assembly  18 . As such, at least a portion of the “interior surface”  20 ′ of the cover structure  20  may be disposed in substantially continuous confronting engagement with the correspondingly disposed surface  18 ′ to facilitate heat transfer through the mounting assembly  18  and the cover structure  20  when interconnected into the assembled orientation of  FIGS. 1 and 2 . Such heat transfer and the eventual dissipation of heat from the control circuitry or driver assembly  16  and illumination structure  12 , through the mounting assembly  18  and the confronting surface portions  18 ′ and  20 ′, is further facilitated by a portion of the surface  20 ′, such as the outer portion of the surface  20 ′, being exposed to the exterior of the light fixture  10 , as best represented in  FIG. 2 . 
     Cooperative structural features of the illumination assembly  12 , the mounting assembly  18 , and the cover structure  20  include an apertured construction comprising the provision of an aperture or opening  24  in a center or other appropriate portion of the cover structure  20 . The opening  24  is disposed, dimensioned and configured to receive the illumination structure  12  therein or at least be in alignment therewith. As such, the light generated by the one or more light emitting diodes  14  pass through the opening  24  so as to be directed or channeled outwardly from the exposed or outermost surface of the cover assembly  20 . The surrounding area is thereby effectively illuminated. 
     Additional structural features associated with the directing or channeling of light from the illumination structure  12  through the opening  24  include a light shield  26  which may be formed of a transparent and/or translucent material such as glass, plastic, etc. The light shield  26  may be structured to further direct or channel, in a more efficient manner, the illumination generated by the LEDs  14  of the illumination assembly  12 . Accordingly, the light shield  26  is disposed in overlying but spaced relation to the opening  24  and to the illumination assembly  12  when the various components of the light fixture assembly  10  are in an assembled orientation as represented in  FIGS. 3 and 4 . 
     Interconnection of the various components into the assembled orientation of  FIG. 3  may be accomplished by a plurality of generally conventional connectors as at  28  and a decorative or utilitarian attachment assembly  29 ,  29 ′,  29 ″, etc. Further, a housing, enclosure, junction box or like structure  30  is provided for the housing of wiring, conductors and other electrical components. Housing  30  is connected to the under surface or rear portion of the mounting assembly  18  and may further include supportive backing plates or the like. These backing plates facilitate the interconnection and support of a remainder of the light fixture assembly  10  when it is attached to or supported by ceiling, wall or other supporting surface or structure. Further, an electrical interconnection to an appropriate source of electrical energy is provided. 
     Therefore, the heat dissipating assembly  100  as represented in  FIG. 4  is operative in the practical application and environment of a light fixture incorporating one or more LEDs such as, but not limited to, the light fixture  10  as set forth above and generally represented in  FIG. 1-3 . 
     More specifically and with primary reference to  FIG. 4 , the heat dissipating assembly  100  of the present invention is structurally and operatively adapted to be used with a light fixture  110  such as of the type, but not limited to, the light fixture  10  disclosed in  FIGS. 1 through 3  and described above. Further, the light fixture  110  includes an illumination structure  112  comprising one or more LEDs  114 . In addition, control circuitry  116  is also included in the illumination structure  112  and includes a driver assembly of the type operatively structured to drive and/or operate the one or more LEDs. For purposes of clarity, the control circuitry and the driver assembly will both be indicated and synonymously referred to as  116 . 
     While not specifically disclosed in the schematic representation of  FIG. 4 , operative interconnecting wiring or other connective circuitry is established through remaining portions of the light fixture  112 , between the driver assembly  116  and the LEDs  114 . Such interactive and cooperatively structured wiring or circuitry may include a printed circuit board or other appropriate circuitry structure  116 ′ and an appropriately structured printed circuit board and/or printed circuitry  115 . However, it is noted that the structure  115  may also serve as or be structured to interconnect and/or secure the one or more LEDs  114  in an appropriate, operative disposition within the light fixture  110 , relative to the remaining components of the heat dissipating assembly  100 . Further by way of example, the structure  115  may be an at least partially structured in the form of a conventional printed circuit board, printed circuitry, connector member, etc. In addition, structure  115  may be formed, at least in part, from a heat conductive material having sufficient heat conductive properties to direct heat away from the one or more LEDs  114  such as through, but not limited to, correspondingly disposed sections or segments  122  of a primary heat sink  120 . 
     Therefore, additional structural features of the heat dissipating assembly  100  include the provision of a primary heat sink  120 . The primary heat sink  120  may substantially or at least partially correspond to the heat sink structure  20  as represented in  FIGS. 1-3 . As such, the one or more LEDs  114  of the illumination structure  112  are mounted in heat communicating relation to the primary heat sink  120  either independently or by virtue of the printed circuitry connector structure  115 , as described above. In addition, the dimension, configuration and overall structure of the primary heat sink  120  is such as to facilitate the transfer or flow of heat away from heat generating components of the heat dissipating assembly  100  including, but not limited to, the driver assembly  116 , to a location or area exteriorly of the illumination structure  112 . Therefore, the primary heat sink  120  serves to transfer heat away from the one or more LEDs  114 , driver  116 , additional control circuitry or electronic components  116 ′, connector structure  115 , etc. 
     Moreover, additional structural and operative features associated with the heat dissipating assembly  100  includes the provision of a “mount” or mounting assembly  118 . The mount  118  is also formed from a heat conductive material and as such may also serve as a heat sink and/or secondary heat sink by virtue of its predetermined disposition in heat transferring relation to the primary heat sink  120 . As clearly represented in  FIG. 4 , the cooperative disposition of the mount  118  and the primary heat sink  120  is such as to establish a heat dissipating flow and/or heat transferring relation therebetween. This may be accomplished by correspondingly disposed surfaces  118 ′ and  120 ′ being disposed in confronting engagement with one another. An alternative construction may also be defined by a more integrated structuring of the mount  118  and primary heat source  120  such as by an integral, one-piece construction thereof. 
     In order to further facilitate the dissipation of heat away from the one or more LEDs  114 , as well as from the driver assembly  116 , a compartment structure generally indicated as  148  comprises an at least partially hollow interior  149  of the chamber  150  in which a heat insulating fluid is present. The heat insulating fluid may be air, other gas or fluids having sufficient heat insulating properties to at least partially insulate the one or more LEDs  114  from heat generated by or derived from heat generating components of the illumination structure  112  such as, but not limited to, the control circuitry or driver assembly  116 . In more specific terms, the at least partially hollow interior  149  of the chamber  150  is disposed adjacent to both the control circuitry and or driver assembly  116 ,  116 ′ and the one or more LEDs  114 . In a preferred embodiment, the chamber  150  and the air or other insulating fluid contained therein is disposed in substantially aligned relation between the driver assembly  116  and the one or more LEDs  114 . 
     As a result of the heat transferring capabilities of both the primary heat sink  120  and the mount or secondary heat sink  118 , heat generated by the driver assembly  116 , as well as other components associated with the illumination structure  112 , will be directed therefrom, through the heat conductive material of the mount  118  and outwardly and away from the LEDs  114 . As schematically represented by the collection of directional arrows included within  FIG. 4 , a “flow path” of heat will be established facilitating the travel of heat from the generating components of the illumination structure  112  through the mount  118 , along the length thereof and/or therefrom through the primary heat sink  120 . The dissipating heat will further be transferred to an area or location exteriorly of the illumination structure  112 , where such heat may be safely dissipated. The existence and presence of the “air pocket” or “heat insulating fluid pocket” within the chamber  150  in aligned, adjacent relation between the driver assembly  116  and one or more LEDs  114  will at least partially but effectively facilitate the transfer of heat away from the one or more LEDs  114  and restrict the passage of heat through the chamber  150  defined by hollow interior  149  of the compartment structure  148 . 
     Yet another embodiment and/or structural modification of the heat dissipating assembly  100 , as represented in  FIG. 4 , may include the absence or at least partial removal of the indicated section or segment  122  of the primary heat sink  120 . For purposes of clarity the referred to segment or section  122  is defined, at least partially, by broken lines  122 ′. However, it is noted that the absence of the segmented portion  122  may at least partially or minimally restrict the transfer of or flow of heat away from the one or more LEDs  114 , such as indicated by corresponding directional arrow  122 ″. 
     Since many modifications, variations and changes in detail can be made to the described preferred embodiment of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents. 
     Now that the invention has been described,