Abstract:
The present invention relates to a LED lens assembly including a lens base, a plurality of lens elements on the lens base, a cable channel on the lens base, a frame at the periphery of the lens base, and clips on the frame. A bottom portion of the frame defines a lip, external to which there is formed a groove for receiving overfill of a sealant. Each of the clips has a trailing portion extending to an edge of the frame. The invention further provides a LED module and a LED light fixture, both incorporating the LED lens assembly. Use of this structure can lead to the following beneficial effects: convenience in mounting; better waterproofing results; and applicability in light used in an obliquely upward orientation, such as flood lights.

Description:
TECHNICAL FIELD 
     The present invention relates to the field of lighting and, more particularly, to LED lens assemblies, and LED modules and LED fixtures incorporating the LED lens assemblies. 
     BACKGROUND 
     In the current context of concerns about global energy shortage rising once again, energy conservation and use of new energy have become a theme that the society should pay common attention to. In the field of lighting, the application of LED lighting products is attracting the world&#39;s attention. As new “green” lighting products, LEDs will surely be the future trend of lighting, and the twenty-first century will be an era of new lighting sources with LEDs as the mainstream. 
     Most conventional LED lenses commonly available in the market are designed to be fixed on a heat dissipation means by means of screws. This design is not convenient for mounting and maintenance. There are also a small number of LED lenses using clips, examples of which include those described in Chinese Patent Nos. CN201836825U, CN201836842U and CN103256559A. Each of these lenses is configured to be deployed over a circuit board that is fixed on a heat dissipation means, and essentially includes: a lens base; lens elements arranged on the lens base; channels for housing screws and cables; seal ring grooves; and clips that are arranged at a periphery of the lens base and adapted to connect the heat dissipation means. 
     Conventional LED modules commonly resort to a resilient sealing ring or sealant-filled surface groove for their waterproofness and incorporate a thermally conductive bottom plate made of an aluminum alloy material. Such design suffers from insufficient water-proofing and heat-dissipating abilities and inconvenience in mounting and maintenance. 
     SUMMARY 
     It is therefore the object of the present invention to provide LED lens assemblies, and LED modules and LED fixtures incorporating the LED lens assemblies, which overcome the inconvenient mounting, unsatisfactory waterproofing and inadequate sealing problems arising from the use of conventional LED lens products. 
     In pursuit of this object, according to an aspect of the present invention: 
     a LED lens assembly includes a lens base, a plurality of lens elements on the lens base, a cable channel on the lens base, a frame at the periphery of the lens base, and clips on the frame. A bottom portion of the frame defines a lip, next to which a groove for receiving overfill of a sealant is formed. Each of the clips has a trailing portion extending to an edge of the frame. 
     Additionally, the cable channel may have a height that is greater than 1 mm, with 1-2 mm being more preferred. 
     Further, alternatively, two grooves for receiving overfill of the sealant may be formed on opposing sides of the lip. 
     Further, the number of the clip may be 3-20. 
     Further, the lens base may assume a triangular, rectangular, pentagonal, hexagonal, heptagonal, octagonal, round or elliptical shape. 
     Further, an arrow may be marked on the lens base in order to indicate a direction of the LED lens assembly. 
     According to another aspect of the invention, a LED module includes the LED lens assembly as defined above. 
     In addition, the LED module may include, from the bottom upward, a heat-conducting bottom plate, a heat-conducting aluminum base plate attached thereon with a plurality of LEDs, and the LED lens assembly. 
     The heat-conducting bottom plate has a mounting surface defining a cable outlet hole, and the heat-conducting aluminum base plate defines another cable outlet hole. A recess for receiving a resilient sealing ring is provided between the cable outlet hole in the heat-conducting aluminum base plate and the cable outlet hole in the heat-conducting bottom plate. A cable extends successively through the cable outlet hole in the heat-conducting bottom plate, the resilient sealing ring and the cable outlet hole in the heat-conducting aluminum base plate and has a portion received in the cable channel of the LED lens assembly and welded therein to the heat-conducting aluminum base plate. The resilient sealing ring is fixed within the recess by an adhesive filled therein such that a waterproof seal is formed. 
     At least one sealing groove is formed in the heat-conducting bottom plate, alongside its periphery. A waterproof seal is formed by filling a sealant in the sealing groove and further inserting the lip on the bottom portion of the frame, during which any overfill of the sealant is received within the groove external to the lip. 
     A heat-conducting silicon resin is applied between the heat-conducting aluminum base plate and the heat-conducting bottom plate. 
     The heat-conducting aluminum base plate is fastened on the heat-conducting bottom plate either by screws or by a piece of double-sided adhesive tape that is thermally conductive. 
     The LED lens assembly is also fastened on the heat-conducting bottom plate through the clips after the filling of the sealant. 
     The heat-conducting bottom plate is provided with securing mechanisms distributed along its periphery or two opposing edges. 
     The heat-conducting bottom plate defines at least one cable outlet groove. 
     Further, at least one LED lamp may be further provided on the heat-conducting aluminum base plate. 
     Further, the heat-conducting bottom plate may have protruding portions matching the respective clips. 
     Further, the heat-conducting bottom plate may be fabricated from a material with a thermal conductivity of higher than 90 W/m·K, selected from silicon carbide, copper, aluminum, aluminum alloys, graphite and ceramics. 
     Further, the heat-conducting bottom plate may have a height of 3-30 mm. 
     According to yet another aspect of the invention, a modular LED light fixture includes a fixture body, waterproof plugs or sealing rings, and a LED-module cable. The fixture body is provided thereon with a mounting surface, an electrical component box and cooling fins. One or more LED modules as defined above are mounted on the mounting surface. 
     In addition, in order for waterproof sealing, the LED-module cable may extend through at least one of the waterproof plugs or sealing rings and a cable inlet bore, into the electrical component box. 
     Further, the cable inlet bore may be tilted at an angle of 0-180°, more preferably, 5-175°, with respect to the mounting surface. 
     The present invention provides the following benefits: 
     (1) It allows more convenient and reliable mounting. 
     (2) Improved waterproofness is resulted from the reception of overfill of a liquid silica gel in groove(s) formed next to the sealing groove. 
     (3) Each of the clips has a strength-improved trailing portion and hence obtains improved ruggedness. 
     (4) The frame 0.2-5 mm higher than the highest internal portion results in improved ruggedness and less deformability of the lens base and makes it possible to block a large amount of rainwater from flowing onto the lens base, which can affect the light distribution or emission performance. 
     (5) LED light fixtures according to the present invention use LED modules not equipped with heat dissipation means and rely instead on the heat dissipation means on their fixture bodies for heat dissipation. This leads to the advantages of convenience in mounting and maintenance, high versatility, low replacement cost, and modifiability for use in various light fixtures with heat dissipation means. 
     (6) LED light fixtures according to the present invention have good waterproof performance ensured by multiple waterproof features including: one or more waterproof plugs or sealing rings and a cable inlet bore in the fixture body arranged in the path of each cable extending into an electrical component box, an waterproof adhesive filled in gaps between lenses and between lenses and the heat-conducting bottom plate, of each LED module; and sealant-sealed resilient sealing rings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic illustration of a clip in a LED lens assembly constructed in accordance with Embodiment 1 of the present invention. 
         FIG. 2  is a schematic, three-dimensional view of the LED lens assembly constructed in accordance with Embodiment 1 of the present invention. 
         FIG. 3  shows a cutaway view taken along line A-A of  FIG. 2  and an enlarged view of the portion I, of the LED lens assembly constructed in accordance with Embodiment 1 of the present invention. 
         FIG. 4  is a schematic, three-dimensional view of a LED module incorporating a LED lens assembly, constructed in accordance with Embodiment 2 of the present invention. 
         FIG. 5  is a cutaway view of the LED module incorporating the LED lens assembly constructed in accordance with Embodiment 2 of the present invention, taken along line B-B of  FIG. 4 . 
         FIG. 6  is another cutaway view of the LED module constructed in accordance with Embodiment 2 of the present invention, taken along line B-B of  FIG. 4 , in which the LED lens assembly is not shown. 
         FIG. 7  is a schematic showing a structure in accordance with Embodiment 3 of the present invention. 
         FIG. 8  is a schematic showing a structure in accordance with Embodiment 4 of the present invention. 
         FIG. 9  is a schematic showing a structure in accordance with Embodiment 5 of the present invention. 
         FIG. 10  is a schematic showing a structure in accordance with Embodiment 6 of the present invention. 
         FIG. 11  is a schematic showing a structure in accordance with Embodiment 7 of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     LED lens assemblies, and LED modules and LED fixtures incorporating the LED lens assemblies according to the present invention are described in greater detail below with reference to several exemplary embodiments, taken in conjunction with the accompanying drawings. It is to be understood that the embodiments set forth below are for the purpose of illustrating the invention rather than limiting its scope. 
     Embodiment 1 
     LED Lens Assembly 
     As shown in  FIGS. 1 to 3 , a LED lens assembly according to this embodiment 1 includes a lens base  1 ; a plurality of lens elements  2  and a cable channel  3 , on lens base  1 ; a frame  4  at the periphery of lens base  1 ; and clips  5  on the frame  4 . In a bottom surface of frame  4 , a groove  7  for receiving overfill of a sealant is defined external to (on the right as shown in the figures in connection with the description of this embodiment) a lip  6  projecting from the bottom surface. Lip  6  can prevent an insufficient sealing effect caused by overfill of the sealant. Frame  4  is 0.2-5 mm higher than the highest internal portion, thus resulting in improved ruggedness and less deformability of lens base  1  and making it possible to block a large amount of rainwater from flowing onto lens base  1  to affect the light distribution or emission. In this embodiment, lens base  1  is a square, and the cable channel is designed to have a height of 1-2 cm. This can result in improved ruggedness and less deformability of lens base  1 , thereby preventing changes in light distribution curves and failure of waterproofness that may be caused by deformation of lens base  1 . The number of clips  5  arranged at the periphery of lens base  1  is 3-30, and each of clips  5  has a trailing portion extending to an edge of frame  4  and thus has improved ruggedness. Further, the lens base is provided an arrow  8  marked thereon for indicating a direction of the LED lens assembly. 
     Embodiment 2 
     LED Module Incorporating LED Lens Assembly 
       FIGS. 4 to 6  show a LED module incorporating a LED lens assembly constructed in accordance with Embodiment  1 . The LED module includes, from the bottom upward, a heat-conducting bottom plate  10 , a heat-conducting aluminum base plate  11  attached with a plurality of LEDs, and the LED lens assembly indicated at  12 . Cable outlet holes  13  and  14  are formed respectively in a mounting surface of heat-conducting bottom plate  10  and in heat-conducting aluminum base plate  11 . A recess  16  for receiving a resilient sealing ring  15  is provided between cable outlet hole  14  in heat-conducting aluminum base plate  11  and cable outlet hole  13  in heat-conducting bottom plate  10 . A cable  17  extends successively through cable outlet hole  13 , resilient sealing ring  15  and cable outlet hole  14 , and has a portion received in cable channel  3  of LED lens assembly  12  and welded therein to heat-conducting aluminum base plate  11 . Resilient sealing ring  15  is fixed within recess  16  after an adhesive is filled therein, thus forming a waterproof seal. A sealing groove  19  is defined in the heat-conducting bottom plate  10  alongside its periphery. With a sealant filled in sealing groove  19 , a waterproof seal is formed by inserting lip  6  projecting from the bottom surface of frame  4  of LED lens assembly  12  in sealing groove  19 . During this process, any overfill of the sealant will be received within groove  7  that is external to lip  6 . A heat-conducting silicon resin is applied between heat-conducting aluminum base plate  11  and heat-conducting bottom plate  10 . Heat-conducting aluminum base plate  11  is fastened on heat-conducting bottom plate  10  either by screws  20  or by a piece of double-sided adhesive tape that is thermally conductive. LED lens assembly  12  is further fastened on heat-conducting bottom plate  10  by means of clips  5  after the filling of the sealant, in such a manner that, after the fastening, the clips reach a level not higher than the mounting surface of heat-conducting bottom plate  10 . Heat-conducting bottom plate  10  is provided with mounting holes  21  distributed along its periphery or two opposing edges, and has protruding portions  22  matching the respective clips. 10-50 LED lamps  23  are disposed on heat-conducting aluminum base plate  11 . In addition, in a backside of heat-conducting bottom plate  10 , there is formed a cable outlet groove  24  leading from cable outlet hole  13 . Heat-conducting bottom plate  10  is fabricated from a material with a thermal conductivity higher than 90 W/m·K, selected from silicon carbide, copper, aluminum, aluminum alloys, graphite and ceramics. 
     Embodiment 3 
     Modular LED Light Fixture 
       FIG. 7  shows a LED light fixture using LED modules constructed in accordance with Embodiment 2. The fixture includes a fixture body  101 , on which there are arranged 4 mounting surfaces  102 , an electrical component box  104 , a band clamp  105  for securing a mounting bracket and cooling fins  106 . Electrical component box  104  is disposed between adjacent ones of mounting surfaces  102 . Band clamp  105  and cooling fins  106  are arranged on the periphery of fixture body  101 . Each of mounting surfaces  102  is provided with a LED module  103 , a waterproof plug  107  and a cable inlet bore  108  tilted at an angle of 5-175° (−5-175°). Cables for LED module  103  are coupled to a power supply and extend into electrical component box  104  via respective waterproof plugs  107  and cable inlet bores  108 . Preferably, each of LED modules  103  is fastened to one of mounting surfaces  102  by means of 8 screws. In this embodiment, LED modules  103  are not provided with any heat dissipation means and heat generated by them after they are mounted on the light fixture is dissipated via the cooling means on fixture body  101 . 
     Embodiment 4 
     Modular LED Light Fixture 
       FIG. 8  shows a modular LED light fixture in another form, including a fixture body  201  and a cover  208 . On fixture body  201 , there are provided a mounting surface  202 , an electrical component box (not shown), cooling fins  206  and a mounting bracket  207 . Mounting surface  202  and the electrical component box are disposed in a lower portion of fixture body  201 . Cooling fins  206  are arranged on a surface of fixture body  201 . Mounting bracket  207  is attached to a side face of fixture body  201 . Mounting surface  202  defines a cable inlet bore  205  and bears a LED module  203 . A cable  204  for LED modules  203  is connected to a power supply and extends into the electrical component box via cable inlet bore  205 . Preferably, LED module  203  is fastened to mounting surface  202  by means of 8 screws. Cover  208  is mounted on fixture body  201  by 4 screws, and a sealing ring  209  is disposed between cover  208  and fixture body  201  for imparting waterproofness to the light fixture. In this embodiment, LED module  203  is not provided with any heat dissipation means and heat generated from it after it is mounted on the light fixture is dissipated via the cooling means on fixture body  201 . 
     Embodiment 5 
     Modular LED Light Fixture 
       FIG. 9  shows a modular LED light fixture in yet another form, including a fixture body  301 . On fixture body  301 , there are provided a mounting surface  302 , an electrical component box (not shown) and cooling fins  307 . Cooling fins  307  are arranged on a bottom side of fixture body  301 . Mounting surface  302  bears two LED modules  303  mounted thereon and defines waterproof plugs  305  and cable inlet bores  306  each tilted at an angle of 5-175° (−5-175°). Cables  304  for LED modules  303  are coupled to a power supply and extend into the electrical component box via respective waterproof plugs  305  and cable inlet bores  306 . Preferably, each of LED modules  303  is fastened to mounting surface  302  by means of 8 screws. In this embodiment, LED modules  303  are not provided with any heat dissipation means and heat generated by them after they are mounted on the light fixture is dissipated via the cooling means on the fixture body  301 . 
     Embodiment 6 
     Modular LED Light Fixture 
       FIG. 10  shows a modular LED light fixture in still another form, including a fixture body  401  and a cover  408 . On fixture body  401 , there are provided a mounting surface  402 , an electrical component box (not shown), a mounting bracket  407  and cooling fins  406 . Cooling fins  406  and mounting bracket  407  are arranged on the periphery of fixture body  401 . Mounting surface  402  and the electrical component box are disposed in a lower portion of fixture body  401 . A LED module  403  is mounted on mounting surface  202  that defines a cable inlet bore  405 . A cable  404  for the LED modules  403  is coupled to a power supply and extends into the electrical component box via cable inlet bore  405 . Preferably, LED module  403  is fastened to mounting surface  402  by means of 8 screws. Cover  408  is mounted on fixture body  401  by 6 screws, and a sealing ring  409  is disposed between cover  408  and fixture body  401  for imparting waterproofness to the light fixture. In this embodiment, LED module  403  is not provided with any heat dissipation means and heat generated from it after it is mounted on the light fixture is dissipated via the cooling means on fixture body  401 . 
     Embodiment 7 
     Modular LED Light Fixture 
       FIG. 11  shows a modular LED light fixture in yet still another form, including a fixture body  501 . On fixture body  501 , there are provided 4 mounting surfaces  502 , an electrical component box (not shown), a band clamp  507  for securing a mounting bracket and cooling fins  506 . Mounting surfaces  102  individually bear 4 LED modules  503  mounted thereon and individually define 4 cable inlet bores  505 . Cables  504  for LED modules  503  are coupled to a power supply and extend into the electrical component box via respective cable inlet bores  505 . Preferably, LED modules  503  are fastened to respective mounting surfaces  502  by screws. In this embodiment, LED modules  503  are not provided with any heat dissipation means and heat generated by them after they are mounted on the light fixture is dissipated via the cooling means on fixture body  501 .