Abstract:
Disclosed is a lamp device. The lamp device includes: 
     a heat radiating body comprising a structure and a plurality of fins, wherein the structure comprises an inner surface and an outer surface such that an opening is formed, and wherein a plurality of the fins extend to the outside from the outer surface of the structure; and 
     a substrate being under a plurality of the fins of the heat radiating body and comprising a plurality of light emitting devices disposed on one side thereof

Description:
[0001]    The present application claims priority under 35 U.S.C. §119(e) of Korean Patent Application No. 10-2010-0091547 filed on Sep. 17, 2010, which is hereby incorporated by reference in its entirety. 
       FIELD 
       [0002]    This embodiment relates to a lamp device. 
       DESCRIPTION OF THE RELATED ART 
       [0003]    A light emitting diode (LED) is an energy device converting electric energy into light energy and has low power consumption, a semi-permanent life span, a rapid response speed, safeness and environment-friendliness as compared with existing light sources like a fluorescent light, an incandescent lamp and the like. 
         [0004]    Therefore, many researches are devoted to substitution of the existing light sources with the LED. The LED is now increasingly used as a light source for lighting devices, for example, a liquid crystal display device, an electric sign, a street lamp, a pilot lamp, a room lamp and the like. 
       SUMMARY 
       [0005]    One embodiment is a lamp device includes: 
         [0006]    a heat radiating body comprising a structure and a plurality of fins, wherein the structure comprises an inner surface and an outer surface such that an opening is formed, and wherein a plurality of the fins extend to the outside from the outer surface of the structure; and 
         [0007]    a substrate being under a plurality of the fins of the heat radiating body and comprising a plurality of light emitting devices disposed on one side thereof 
         [0008]    Another embodiment is a lamp device includes: 
         [0009]    a heat radiating body comprising a structure, a plurality of fins and a flat portion, wherein the structure comprises an inner surface and an outer surface such that an opening is formed, wherein a plurality of the fins extend to the outside from the outer surface of the structure, and wherein the flat portion is joined to one ends of a plurality of the fins; 
         [0010]    a substrate comprising a top surface on the flat portion of the heat radiating body; and 
         [0011]    a plurality of light emitting devices disposed on the bottom surface opposite to the top surface of the substrate. 
         [0012]    Further another embodiment is a lamp device includes: 
         [0013]    a heat radiating body comprising a structure and a plurality of fins, wherein the structure comprises an inner surface and an outer surface such that an opening is formed and wherein a plurality of the fins extend to the outside from the outer surface of the structure, wherein two adjacent fins among a plurality of the fins of the heat radiating body are spaced from each other at a regular interval; and 
         [0014]    a substrate contacting with a plurality of the fins of the heat radiating body and comprising a plurality of light emitting devices disposed on one side thereof and a plurality of holes disposed therein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a perspective view of a lamp device according to an embodiment of the present invention. 
           [0016]      FIG. 2  is a perspective view of a cross section of the lamp device according to the embodiment shown in  FIG. 1  of the present invention. 
           [0017]      FIG. 3  is an exploded perspective view of a lamp device according to the embodiment shown in  FIG. 1  of the present invention. 
           [0018]      FIG. 4  is a perspective view of another lamp device according to an embodiment of the present invention. 
           [0019]      FIG. 5  is an exploded perspective view of the lamp device according to the embodiment shown in  FIG. 4  of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0020]    A thickness or size of each layer is magnified, omitted or schematically shown for the purpose of convenience and clearness of description. The size of each component does not necessarily mean its actual size. 
         [0021]    It will be understood that when an element is referred to as being ‘on’ or “under” another element, it can be directly on/under the element, and one or more intervening elements may also be present. When an element is referred to as being ‘on’ or ‘under’, ‘under the element’ as well as ‘on the element’ can be included based on the element. 
         [0022]    Hereinafter, an embodiment will be described with reference to the accompanying drawings. 
         [0023]      FIG. 1  is a perspective view of a lamp device according to an embodiment of the present invention.  FIG. 2  is a perspective view of a cross section of the lamp device according to the embodiment shown in  FIG. 1  of the present invention.  FIG. 3  is an exploded perspective view of a lamp device according to the embodiment shown in  FIG. 1  of the present invention. 
         [0024]    Referring to  FIGS. 1 to 3 , a lamp device  100  according to an embodiment of the present invention includes a heat radiating body  110 , a substrate  130 , a light source unit  150 , a light guider  170 , a flange  190 , a first member  210 , a condensing lens  220 , a second member  230  and a fixing member  250 . 
         [0025]    The heat radiating body  110  is formed by organically coupling a ring structure  111 , a plurality of fins  113  and a flat portion  115 , so that the heat radiating body  110  has a shape of a donut. However, the shape of the heat radiating body  110  is not limited to this. For example, the heat radiating body  110  may have a polygonal shape or other various shapes. 
         [0026]    The ring structure  111  has an inner surface and an outer surface such that an opening  01  having a central axis “A” is formed in the center of the ring structure  111 . A plurality of the fins  113  are joined to the outer surface of the ring structure  111  and radially extend to the outside from the outer surface of the ring structure  111 . A plurality of the fins  113  may be separated from each other at a regular interval such that heat generated from a light source unit  150  which will be described below is wholly uniformly radiated to the outside. The flat portion  115  is joined to one end of the outer surface of the ring structure  111  and extends perpendicular to the outer surface of the ring structure  111 . The flat portion  115  is joined to one ends of a plurality of the fins  113  joined to the outer surface of the ring structure  111 . 
         [0027]    The substrate  130  includes a top surface and a bottom surface. The top surface comes in surface contact with the flat portion  115  of the heat radiating body. The light source unit  150  is disposed on the bottom surface. It is desirable that a commonly used metal printed circuit board (PCB) is mainly used as the substrate  130 . However, any substrate capable of including the light source unit can be used as the substrate  130 . 
         [0028]    The substrate  130  has a disk shape for sealing the ring structure  111  having the opening Gl. In addition, the substrate  130  is required to have an opening G 2  in the center thereof in order that heat generated from the light source unit  150  can be radiated to the outside through the circulation of the air. The opening G 2  at the center of the substrate is placed corresponding to the opening G 1  of the heat radiating body such that they have the same central axis “A”. Here, it is required that the opening G 2  at the center of the substrate and the opening G 1  of the heat radiating body have the same area for the purpose of improving the assemblability and heat radiating characteristic of the lamp device. 
         [0029]    The light source unit  150  includes a plurality of light emitting diodes (LEDs). A plurality of the LEDs are radially disposed on the bottom surface of the substrate. That is, a plurality of the LEDs may be disposed on the bottom surface of the substrate  130  at a regular interval just like a plurality of the fins  113  are disposed. 
         [0030]    As such, when a plurality of the LEDs are radially disposed on the substrate, the radiation area of heat generated from the operation of the LEDs becomes greater, so that heat release efficiency is improved. The heat from the LEDs is radiated through the surface contact between the flat portion of the heat radiating body and the top surface of the substrate and through a plurality of the fins of the heat radiating body, As a result, heat radiating surface area is increased so that a heat transfer characteristic is improved. 
         [0031]    Though not shown in the drawings, a conductive sheet for radiating heat is further added between the substrate  130  and the flat portion  115  of the heat radiating body  110 , so that it is possible to enhance the heat transfer characteristic between the substrate  130  and the heat radiating body  110 . 
         [0032]    Since a plurality of the LEDs are mounted and disposed on one substrate instead of separate substrates, if necessary, it is possible to easily repair and maintain the substrate including the light source unit. 
         [0033]    The light guider  170  includes a plurality of optical fibers. One end of each optical fiber is optically connected to a plurality of the LEDs  150 . In the present embodiment, though the optical fiber is taken as an example of the light guider  170 , any device like a prism of an optical device capable of changing the direction of light generated by the light source unit into a desired direction can be used as the light guider  170 . 
         [0034]    The flange  190  includes a plurality of holes  191  for inserting and binding the ends of a plurality of the optical fibers, and has an entire shape of a disk. Therefore, a plurality of the LEDs are bound by the flange  190 , so that a wide emission area of light generated from a plurality of the radially disposed LEDs becomes smaller. As a result, the light is collected in a particular direction. 
         [0035]    The ends of the optical fibers inserted into the holes  191  of the flange  190  are aligned with the holes  191  of the flange such that the ends are placed on the same plane. This intends to obtain the uniform intensity of light at a particular plane on which the light is incident. The flange is seated in an opening G 3  of the first member  210  which will be described below, so that the flange has an optical orientation plane according to the adjustment of the angle of the first member  210 . 
         [0036]    The first member  210  includes a first projection  212 , a second projection  213  and a first ring structure  211  having an inner surface and an outer surface such that a circular opening G 3  having a central axis is formed in the center of the first ring structure  211 . The first projection  212  and the second projection  213  are formed on the outer surface of the first ring structure  211  to face each other. The first projection  212  and the second projection  213  extend from the outer surface of the first ring structure  211  to the outside. The first projection  212  and the second projection  213  of the first member  210  are inserted into a first hole  231   a  and a second hole  231   b  of the second member  230 , which are described below, respectively. Accordingly, the first member  210  is joined and fixed to the second member  230 . 
         [0037]    The first member  210  is inclined at an angle to rotate about the first projection  212  and the second projection  213 . Therefore, light generated from the light source unit  150  can be directed to a direction that a user desires by through adjustment of the angle of the first member  210 . 
         [0038]    The condensing lens  220  is optically joined to the first member  210  and covers the opening opposite to the first member&#39;s circular opening in which the flange  190  is seated. Such a condensing lens more optically condenses the light which has been physically condensed by the flange. 
         [0039]    Like the first member  210 , the second member  230  includes a first projection  232 , a second projection  233  and a second ring structure  231  having an inner surface and an outer surface such that a circular opening G 4  having a central axis is formed in the center of the second ring structure  231 . The second member  230  includes the first hole  231   a  and the second hole  231   b  into which the first and the second projections  212  and  213  of the first member  210  are inserted. The first hole  231   a  and the second hole  231   b  penetrate the inner and outer surfaces of the second ring structure  231  and face each other. The first and the second projections  232  and  233  extend from the outer surface of the second ring structure  231  to the outside. 
         [0040]    In such a second member  230 , a first imaginary line horizontally extending from the first projection  232  to the second projection  233  is at a right angle to a second imaginary line extending from the central axis of the first hole  231   a  to the central axis of the second hole  231   b.    
         [0041]    The circumferential extent of the inner surface of the second member  230  is greater than that of the outer surface of the first member  210 , so that the first member  210  is inserted into the second member  230 . 
         [0042]    The fixing member  250  includes an inner circumferential portion  251  such that a circular opening G 5  having a central axis of the inner circumferential portion  251  is formed, an outer circumferential portion  253  formed along the inner circumferential portion at a regular interval from the inner circumferential portion  251 , and flat portion  255  extending vertically from the end of the inner circumferential portion to the end of the outer circumferential portion. 
         [0043]    The inner circumferential portion  251  of the fixing member  250  includes mutually facing first and second holes  251   a  and  251   b  into which the first projection  232  and the second projection  233  are inserted. The first projection  232  and the second projection  233  of the second member  230  are respectively inserted into the first hole  251   a  and the second hole  251   b  of the fixing member  250 . The second member  230  is joined and fixed to inner surface of the inner circumferential portion  251  of the fixing member  250 . 
         [0044]    The outer circumferential portion  253  of the fixing member  250  surrounds the light source unit  150  and the light guider  170 . 
         [0045]    Since the lamp device mentioned above includes a heat radiating body having a structure in which the heat generated from the light emitting diodes can be radiated spatially not in an up-and-down direction but in a horizontal direction when the lamp device is operated, the entire volume of the lamp device can be actually reduced. Accordingly, as compared with a conventional heat radiating body radiating heat in the up-and-down direction, the heat radiating body of the present invention has a lower spatial limitation when the lamp device is installed. As a result, installation flexibility can be improved. 
         [0046]      FIG. 4  is a perspective view of another lamp device according to an embodiment of the present invention.  FIG. 5  is an exploded perspective view of the lamp device according to the embodiment shown in  FIG. 4  of the present invention. 
         [0047]    Referring to  FIGS. 4 to 5 , another lamp device  300  according to one embodiment of the present invention includes a heat radiating body  310 , a heat radiating plate  330 , a substrate  350 , a light source unit  370 , a light guider  390 , a flange  410 , a first member  430 , a second member  450  and a fixing member  470 . 
         [0048]    The heat radiating body  310  is formed by organically coupling a ring structure  311  and a plurality of fins  313 , so that the heat radiating body  310  has a shape of a donut. However, the shape of the heat radiating body  310  is not limited to this. For example, the structure  311  may have a polygonal shape or other various shapes. The ring structure  311  has an inner surface and an outer surface such that an opening G 1 ′ having a central axis “A” is formed in the center of the ring structure  311 . A plurality of the fins  313  which are joined to the outer surface of the ring structure  311  and radially extend to the outside from the outer surface of the ring structure  311 . A plurality of the fins  313  are separated from each other at a regular interval such that heat generated from a light source unit  370  which will be described below is wholly uniformly radiated to the outside. That is, two adjacent fins may be spaced apart from each other at a regular interval. 
         [0049]    The heat radiating plate  330  includes a hole  331  located at an area corresponding to the interval between the two adjacent fins among a plurality of the fins  313 , and contacts with a plurality of the radially disposed fins  313 . The heat radiating plate  330  also includes a central opening G 2 ′ placed corresponding to the central opening G 1 ′ of the heat radiating body  310 . The hole  331  of the heat radiating plate  330  has a rectangular shape which is actually parallel with the longitudinal direction of the fin such that the external air more easily flows in from the top of the heat radiating body. When the substrate directly contacts with a plurality of the fins of the heat radiating body, the heat radiating plate  330  may be omitted. If the heat radiating plate  330  is integrally formed with the heat radiating body  310 , the heat radiating body  110  shown in  FIG. 3  can be actually formed. In other words, the heat radiating plate  330  is able to function as the flat portion  115  of the heat radiating body  110  shown in  FIG. 3 . 
         [0050]    The substrate  350  includes a top surface and a bottom surface. The top surface comes in surface contact with the heat radiating plate  330 . The light source unit  370  is disposed on the bottom surface. It is desirable that a commonly used metal printed circuit board (PCB) is mainly used as the substrate  350 . However, any substrate capable of including the light source unit can be used as the substrate  350 . 
         [0051]    The substrate  350  has a disk shape for sealing the heat radiating plate  330  having the opening G 2 ′. In addition, the substrate  350  is required to have an opening G 3 ′ in the center thereof in order that heat generated from the light source unit  370  can be radiated to the outside through the circulation of the external air. Here, the opening G 3 ′ at the center of the substrate  350  is placed corresponding to the opening G 2 ′ of the heat radiating plate  330 . Additionally, the substrate  350  includes a plurality of holes  351 . A plurality of the holes  351  are placed between the light source units  370  which will be disposed on the bottom surface of the substrate. 
         [0052]    It is more desirable that the holes of the substrate are disposed between the light source units  370  and correspond to the holes  331  of the heat radiating plate  330 . Like the hole  331  of the heat radiating plate  330 , the hole  351  of the substrate has also a rectangular shape. 
         [0053]    Though not shown in the drawings, the substrate  350  is able to directly contact with a plurality of the fins of the heat radiating body and transfer heat without the heat radiating plate. It is possible to improve the heat transfer characteristic between the heat radiating body and the heat radiating plate or between the heat radiating plate and the substrate by adding a conductive sheet between the heat radiating body and the heat radiating plate or between the heat radiating plate and the substrate. 
         [0054]    The light source unit  370  includes a plurality of light emitting diodes (LEDs). A plurality of the LEDs are radially disposed on the bottom surface of the substrate. That is, a plurality of the LEDs are disposed on the bottom surface of the substrate  350  just like a plurality of the fins  313  of the heat radiating body  310  are disposed. 
         [0055]    As such, when a plurality of the LEDs are radially disposed on the substrate, the radiation area of heat generated from the operation of the LEDs becomes greater, so that heat release efficiency is improved. The heat from the LEDs can be radiated by the circulation of the air through the holes of either the substrate or the heat radiating plate. A plurality of the fins of the heat radiating body increase the heat radiation surface area, so that a heat transfer characteristic is improved. Though not shown in the drawings, a conductive sheet for radiating heat is further added between the substrate and the heat radiating plate, so that it is possible to enhance the heat transfer characteristic between the substrate and the heat radiating plate. 
         [0056]    Since a plurality of the LEDs are mounted and disposed on one substrate instead of separate substrates, if necessary, it is possible to easily repair and maintain the substrate including the light source unit. 
         [0057]    Since the light guider  390 , the flange  410 , the first member  430 , a condensing lens  440 , the second member  450  and the fixing member  470  are similar to those of the one embodiment of the present invention, the descriptions thereof will be omitted. 
         [0058]    The features, structures and effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. Furthermore, the features, structures and effects and the like provided in each embodiment can be combined or modified in other embodiments by those skilled in the art to which the embodiments belong. Therefore, the contents related to the combination and modification should be construed to be included in the scope of the present invention. 
         [0059]    The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the foregoing embodiments is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures.