Patent Publication Number: US-10309609-B2

Title: Lighting device for vehicle and lighting tool for vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2016-161314, filed on Aug. 19, 2016; the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a lighting device for vehicle, and a lighting tool for vehicle. 
     BACKGROUND 
     There is a lighting device for vehicle which includes a socket, and a light emitting module which is provided on one end face of the socket, and includes a light emitting diode (LED). 
     Heat generated in the light emitting diode is mainly radiated to the outside through the socket. 
     For this reason, a plurality of thin plate-shaped heat radiating fins are provided in the socket. 
     In addition, the heat radiating fin is provided on a side of the socket opposite to a side on which the light emitting module is provided. 
     Here, when the lighting device for vehicle is mounted on a lighting tool for vehicle, an end portion of the socket on the side on which the light emitting module is provided is inserted into a hole provided in the lighting tool for vehicle, the lighting device for vehicle is rotated, and is held in the lighting tool for vehicle. Such a mounting method is referred to as twist-lock. When the lighting device for vehicle is mounted on the lighting tool for vehicle, a worker grips a side of the socket opposite to the side on which the light emitting module is provided. In this case, since the heat radiating fin is provided on the side of the socket opposite to the side on which the light emitting module is provided, the worker grips the heat radiating fin. 
     Here, in the lighting device for vehicle, the number of heat radiating fins provided in a predetermined region is increased, by making a thickness of the heat radiating fin small. However, since a worker grips the heat radiating fin when mounting the lighting device for vehicle, there is a concern that the thin plate-shaped heat radiating fin may be damaged. In recent years, a socket formed of a high heat conductive resin is proposed in order to make the lighting device for vehicle lightweight. However, there is a problem in that intensity of a high heat conductive resin into which filler is mixed decreases. For this reason, when adopting a socket formed of a high heat conductive resin, damage of the heat radiating fin more easily occurs when a worker grips the heat radiating fin. 
     Therefore, there is a desire for a development of a technology in which it is possible to suppress damage of a heat radiating member, and improve a heat radiating property. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic perspective view which exemplifies a lighting device for vehicle according to an embodiment. 
         FIG. 2  is a schematic view in which the lighting device for vehicle is viewed in a direction A in  FIG. 1 . 
         FIG. 3  is a schematic perspective view which exemplifies a heat radiating portion according to another embodiment. 
         FIG. 4  is a schematic perspective view which exemplifies a heat radiating portion. 
         FIG. 5  is a schematic perspective view which exemplifies a heat radiating portion. 
         FIG. 6  is a schematic perspective view which exemplifies a heat radiating portion. 
         FIG. 7  is a schematic and partial sectional view which exemplifies a lighting tool for vehicle. 
     
    
    
     DETAILED DESCRIPTION 
     A lighting device for vehicle according to one embodiment includes a plate-shaped flange; a placing portion which is provided on a first face of the flange; a light emitting module which is provided at an end face of the placing portion, and includes a light emitting element; a plurality of heat radiating fins which are formed in a plate shape, and provided on a second face of the flange on a side opposite to the first face; a plurality of first protrusion portions which are provided on the second face of the flange in a line, in a direction intersecting a direction in which the plurality of heat radiating fins are aligned; and a second protrusion portion which is provided on the second face of the flange on a side opposite to the plurality of first protrusion portions, by interposing the plurality of heat radiating fins therebetween. 
     Hereinafter, the embodiment will be exemplified with reference to drawings. In addition, in each figure, the same reference numerals are attached to the same constituent elements, and detailed descriptions thereof will be appropriately omitted. 
     Lighting Device for Vehicle 
     A lighting device for vehicle  1  according to the embodiment can be provided in a vehicle, a railway vehicle, or the like, for example. As the lighting device for vehicle  1  provided in a vehicle, for example, it is possible to exemplify a device which is used in a front combination light (for example, light in which daytime running lamp (DRL), position lamp, turn signal lamp, and the like, are appropriately combined), a rear combination light (for example, stop lamp, tail lamp, turn signal lamp, back lamp, fog lamp, and the like, are appropriately combined), or the like. However, a use of the lighting device for vehicle  1  is not limited to these. 
       FIG. 1  is a schematic perspective view for exemplifying the lighting device for vehicle  1  according to the embodiment. 
       FIG. 2  is a perspective view in which the lighting device for vehicle  1  is viewed in a direction A in  FIG. 1 . 
     As illustrated in  FIGS. 1 and 2 , a socket  10 , a light emitting module  20 , and a power feeding unit  30  are provided in the lighting device for vehicle  1 . 
     The socket  10  includes a receiving portion  10   a  and a heat radiating portion  10   b.    
     The receiving portion  10   a  includes a mounting unit  11 , a bayonet  12 , and an insulating portion  13 . 
     The mounting unit  11  is formed in a tubular shape. The mounting unit  11  can be set to a cylindrical shape, for example. The mounting unit  11  is provided on a face  14   a  (corresponding to an example of first face) of a flange  14  on a side opposite to a face  14   b  (corresponding to an example of second face) on which a heat radiating fin  16  is provided. The mounting unit  11  surrounds a placing portion  15 . 
     The bayonet  12  is provided on a side face of the mounting unit  11 , and protrudes toward the outside of the lighting device for vehicle  1 . The bayonet  12  faces the flange  14 . A plurality of the bayonets  12  are provided. The bayonet  12  is used when attaching the lighting device for vehicle  1  to a lighting tool for vehicle  100  using twist-lock. 
     The insulating portion  13  is provided inside the mounting unit  11 . 
     The receiving portion  10   a  can be formed by integrally molding the mounting unit  11 , the bayonet  12 , and the insulating portion  13 , or can be formed by bonding thereof. 
     The receiving portion  10   a  has a function of receiving the light emitting module  20 , and a function of insulating a power feeding terminal  31 . For this reason, it is preferable to form the mounting unit  11 , the bayonet  12 , and the insulating portion  13  using an insulating material. The insulating material can be set to an organic material such as a resin, for example, or an inorganic material such as ceramic (for example, aluminum oxide, or aluminum nitride), or the like. 
     The heat radiating portion  10   b  includes the flange  14 , the placing portion  15 , the heat radiating fin  16 , a terminal cover  17 , a protrusion portion  18  (corresponding to an example of first protrusion portion), and a protrusion portion  19  (corresponding to an example of second protrusion portion). 
     The flange  14  is formed in a plate shape. The flange  14  can be set to a flange formed in a disk shape, for example. An outer face of the flange  14  is located in the outside of the lighting device for vehicle  1 , rather than the outer face of the bayonet  12 . 
     The placing portion  15  can be set to a columnar shape. The placing portion  15  is provided on the face  14   a  of the flange  14  on a side opposite to the face  14   b  on which the heat radiating fin  16  is provided. A recessed portion is provided on a side face of the placing portion  15 . The insulating portion  13  is provided inside the recessed portion. The light emitting module  20  (substrate  21 ) including a light emitting element  22  is provided on an end face  15   b  of the placing portion  15 . 
     In addition, it is possible to provide a layer, or the like, formed of a metal substrate (not illustrated), heat conductive grease, or an adhesive between a face of the light emitting module  20  (substrate  21 ) on a side opposite to a side on which the light emitting element  22  is provided and the end face  15   b  of the placing portion  15 , in order to increase a heat radiating property. 
     The heat radiating fin  16  is provided on the face  14   b  of the flange  14  on a side opposite to the face  14   a . A plurality of the heat radiating fins  16  are provided. The plurality of heat radiating fins  16  can be provided so as to be parallel to each other. The heat radiating fin  16  can be set to a flat-plate shape. 
     The terminal cover  17  has a function of protecting an end portion of the power feeding terminal  31 , and a function of holding a connector  105 . The terminal cover  17  is provided on the face  14   b  of the flange  14 . The insulating portion  13  in which the power feeding terminal  31  is provided is provided at a position deviated from a peripheral edge of the flange  14  toward a center side. For this reason, the terminal cover  17  is also provided at a position deviated from the peripheral edge of the flange  14  toward the center side. The terminal cover  17  can be set to a rectangular tubular shape, for example. An end portion of the power feeding terminal  31  protrudes in the terminal cover  17 . The connector  105  including a sealing member is mounted on the terminal cover  17 . 
     The protrusion portions  18  and  19  are provided on the face  14   b  of the flange  14 . The protrusion portions  18  and  19  will be described later in detail. 
     A heat radiating portion  10   b  can be formed by integrally molding the flange  14 , the placing portion  15 , the heat radiating fin  16 , the terminal cover  17 , and the protrusion portions  18  and  19 , or it is also possible to bond these elements, by separately forming thereof. 
     The heat radiating portion  10   b  has a function of placing the light emitting module  20 , and a function of radiating heat generated in the light emitting module  20  to the outside. For this reason, it is preferable to form the heat radiating portion  10   b  using a material with high heat conductivity by taking the function of radiating heat into consideration. It is possible to set the material with high heat conductivity to, for example, metal such as aluminum, or an aluminum alloy, ceramic such as aluminum oxide, or aluminum nitride, a high heat conductive resin, or the like. The high heat conductive resin is obtained by mixing filler formed of aluminum oxide with high heat conductivity, or carbon into a resin such as polyethylene terephthalate (PET), or nylon, for example. 
     The heat radiating portion  10   b  is bonded to the receiving portion  10   a . The receiving portion  10   a  and the heat radiating portion  10   b  may be fitted to each other, may be bonded using an adhesive, or the like, may be integrally molded using an insert molding method, or, may be bonded using heat welding. 
     In addition, it is also possible to integrally mold the receiving portion  10   a  and the heat radiating portion  10   b . For example, it is also possible to set the socket  10  (receiving portion  10   a  and heat radiating portion  10   b ) to be integrally molded using a high heat conductive resin, or the like. In this case, when forming at least any one of the receiving portion  10   a  and the heat radiating portion  10   b  using a high heat conductive resin, it is possible to obtain a lighting device for vehicle  1  which is lightweight, and of which a heat radiating property is improved. 
     The light emitting module  20  is provided on the end face  15   b  of the placing portion  15 . 
     The light emitting module  20  includes the substrate  21 , the light emitting element  22 , a resistor  23 , and a diode  24 . 
     The substrate  21  is provided on the face  15   b  of the placing portion  15 . The substrate  21  is formed in a flat-plate shape. A wiring pattern  25  is provided on the surface of the substrate  21 . A material or a structure of the substrate  21  is not particularly limited. For example, the substrate  21  can be formed of an inorganic material such as ceramic (aluminum oxide, aluminum nitride, or the like), an organic material such as paper phenol, glass epoxy, or the like. In addition, the substrate  21  may be a substrate obtained by covering the surface of metal with an insulating material. The substrate  21  may be a single layer, or a multiple layer. 
     The light emitting element  22  is provided on the substrate  21 . The light emitting element  22  is electrically connected to the wiring pattern  25  which is provided on the surface of the substrate  21 . The light emitting element  22  can be set to, for example, a light emitting diode, an organic light emitting diode, a laser diode, or the like. 
     A form of the light emitting element  22  is not particularly limited. 
     The light emitting element  22  can be set to a surface mounting-type light emitting element such as a plastic leaded chip carrier (PLCC) type. The light emitting element  22  exemplified in  FIG. 1  is the surface mounting-type light emitting element. 
     The light emitting element  22  can also be set to a light emitting element including a lead wire of a cannonball type, or the like. 
     The light emitting element  22  can also be set to an element which is mounted using a chip on board (COB). When it is set to the light emitting element  22  which is mounted, using the COB, a chip-shaped light emitting element  22 , wiring which electrically connects the light emitting element  22  and the wiring pattern  25 , a frame-shaped member which surrounds the light emitting element  22  and the wiring, a sealing portion which is provided inside the frame-shaped member, and the like, can be provided on the substrate  21 . In this case, a phosphor can be contained in the sealing portion. The phosphor can be set to an yttrium-aluminum-garnet-based phosphor (YAG), for example. However, a type of the phosphor is not particularly limited to the example, and can be appropriately changed so as to obtain a desired luminescent color according to a use of the lighting device for vehicle  1 , or the like. 
     The resistor  23  is provided on the substrate  21 . The resistor  23  is electrically connected to the wiring pattern  25  provided on the surface of the substrate  21 . The resistor  23  controls a current which flows in the light emitting element  22 . 
     Since there is unevenness in forward voltage characteristics of the light emitting element  22 , when setting an application voltage between an anode terminal and a ground terminal to be constant, there is unevenness in brightness (light flux, luminance, intensity of light, illuminance) of the light emitting element  22 . For this reason, it is set so that a value of current which flows in the light emitting element  22  falls in a predetermined range using the resistor  23 , in order for the brightness of the light emitting element  22  to fall in a predetermined range. In this case, it can be set so that a value of current which flows in the light emitting element  22  falls in a predetermined range, by changing a resistance value of the resistor  23 . 
     The resistor  23  can be set to a surface mounting-type resistor, a resistor with a lead wire (metal oxide film resistor), a film-shaped resistor, or the like, which is formed, using a screen printing method, or the like. The resistor  23  exemplified in  FIG. 1  is a film-shaped resistor. The number, a size, an arrangement, and the like, of the resistor  23  are not limited to the example, and can be appropriately changed according to the number, a specification, or the like, of the light emitting element  22 . 
     The diode  24  is provided on the substrate  21 . The diode  24  is electrically connected to the wiring pattern  25  which is provided on the surface of the substrate  21 . The diode  24  can be set to, for example, a surface mounting-type diode, a diode including a lead wire, or the like. The diode  24  exemplified in  FIG. 1  is the surface mounting-type diode. The diode  24  can be provided on an input side of the light emitting module  20 . The diode  24  is provided so as to cause a backward voltage is not applied to the light emitting element  22 , and cause a pulse noise from a reverse direction is not applied to the light emitting element  22 . 
     In addition to that, it is also possible to provide a covering portion which covers the wiring pattern  25  or the film-shaped resistor. The covering portion can be set to a portion containing a glass material, for example. In addition, it is also possible to provide a pull-down resistor in order to detect disconnection of the light emitting element  22 , prevent erroneous lighting, or the like. 
     The power feeding unit  30  includes a plurality of power feeding terminals  31 . The plurality of power feeding terminals  31  are provided inside the socket  10  (insulating portion  13 ). One end portion of the plurality of power feeding terminals  31  protrudes from an end face of the insulating portion  13  on a side opposite to the flange  14  side, and is electrically connected to the wiring pattern  25  provided on the substrate  21 . The other end portion of the plurality of power feeding terminals  31  protrudes from the end face of the insulating portion  13  on the flange  14  side. The other end portion of the plurality of power feeding terminals  31  is exposed to the inside of the terminal cover  17 . In addition, the number, a shape, or the like, of the power feeding terminal  31  is not limited to the example, and can be appropriately changed. 
     Subsequently, the protrusion portions  18  and  19  will be further described later. 
     The protrusion portion  18  can be set to a block shaped. By setting to the protrusion portion  18  formed in a block shape, rigidity of the protrusion portion  18  becomes higher than that of the heat radiating fin  16 . The protrusion portion  18  protrudes from the face  14   b  of the flange  14 . The protrusion portion  18  is provided in the vicinity of the peripheral edge of the flange  14 . A plurality of the protrusion portions  18  can be provided. In a case of the example illustrated in  FIG. 2 , two protrusion portions  18  are provided. The terminal cover  17  is provided between the plurality of protrusion portions  18 . The plurality of protrusion portions  18  and the terminal cover  17  can be provided in a line, in a direction intersecting a direction in which the plurality of heat radiating fins  16  are aligned. A distance from the face  14   b  of the flange  14  to an end face of the protrusion portion  18  can be set to be approximately the same as the distance from the face  14   b  of the flange  14  to an end face of the terminal cover  17 . 
     Here, since the connector  105  is mounted on the terminal cover  17 , it is difficult to make an external dimension (wall thickness dimension) of the terminal cover  17  large. For this reason, there is a case in which resistance of the terminal cover  17  to an external force decreases. In the lighting device for vehicle  1  according to the embodiment, the terminal cover  17  is provided between the plurality of protrusion portions  18 . In addition, the plurality of protrusion portions  18  are provided in the vicinity of the peripheral edge of the flange  14 , and the terminal cover  17  is provided at a position deviated from the peripheral edge of the flange  14  toward the center side. For this reason, it is possible to suppress an addition of an external force to the terminal cover  17 . 
     The protrusion portion  19  can be set to a block shape. By setting the protrusion portion  19  to the block shape, rigidity of the protrusion portion  19  increases compared to that of the heat radiating fin  16 . The protrusion portion  19  protrudes from the face  14   b  of the flange  14 . The protrusion portion  19  is provided in the vicinity of the peripheral edge of the flange  14 . The protrusion portion  19  is provided on a side opposite to the plurality of protrusion portions  18  by interposing the plurality of heat radiating fins  16  therebetween. For this reason, both sides of the columns of the plurality of heat radiating fins  16  are surrounded with the plurality of protrusion portions  18  and the protrusion portion  19 . 
     A distance from the face  14   b  of the flange  14  to an end face of the protrusion portion  19  can be set to be approximately the same as a distance from the face  14   b  of the flange  14  to an end face of the plurality of heat radiating fins  16 . 
     In addition, a distance from the face  14   b  of the flange  14  to an end face of the protrusion portion  18  can be set to be approximately the same as a distance from the face  14   b  of the flange  14  to the end face of the plurality of heat radiating fins  16 . 
     Here, when making the thickness of the plurality of heat radiating fins  16  small, it is possible to increase the number of heat radiating fins  16  which are provided in a predetermined region. When it is possible to increase the number of heat radiating fins  16 , it is possible to make a heat radiating area large. For this reason, the thickness of the heat radiating fins  16  becomes small, in general. When making the thickness of the heat radiating fin  16  small, resistance of the heat radiating fin  16  to an external force decrease. In the lighting device for vehicle  1  according to the embodiment, both sides of the columns of the plurality of heat radiating fins  16  are surrounded with the plurality of protrusion portions  18  and the protrusion portion  19 . For this reason, it is possible to suppress an addition of an external force to the plurality of heat radiating fins  16 . 
     As will be described later, when a worker mounts the lighting device for vehicle  1  on the lighting tool for vehicle  100 , the worker grips the heat radiating portion  10   b  of the lighting device for vehicle  1 . In this case, the plurality of heat radiating fins  16  with low rigidity and the terminal cover  17  are provided in the heat radiating portion  10   b . For this reason, when the worker grips the plurality of heat radiating fins  16  and the terminal cover  17 , there is a concern that these may be damaged. In addition, a high heat conductive resin containing filler has lower rigidity than that of a resin, metal, or the like. For this reason, when forming the heat radiating portion  10   b  using the high heat conductive resin, the plurality of heat radiating fins  16  and the terminal cover  17  are more easily damaged. 
     Meanwhile, there is a little restriction related to an external dimension, a wall thickness, or the like, in the protrusion portions  18  and  19 . For this reason, the protrusion portions  18  and  19  can be set so as to have high rigidity compared to the plurality of heat radiating fins  16  and the terminal cover  17 . In addition, the protrusion portions  18  and  19  are provided on the peripheral edge side of the flange  14 , compared to the position in which the plurality of heat radiating fins  16  and the terminal cover  17  are provided. For this reason, when the lighting device for vehicle  1  is mounted on the lighting tool for vehicle  100  by a worker, the worker can easily grip the protrusion portion  18  and the protrusion portion  19  with high rigidity. As a result, when the lighting device for vehicle  1  is mounted on the lighting tool for vehicle  100  by the worker, it is possible to prevent the plurality of heat radiating fins  16  and the terminal cover  17  from being damaged. 
     According to a knowledge obtained by inventors of the exemplary embodiment, it was clarified that it is not possible to improve a heat radiating property when the thickness of the plurality of heat radiating fins  16  is set to be excessively small. As described above, it is considered that an improvement of heat radiating property can be obtained, by increasing the number of heat radiating fins  16  which is provided in a predetermined region by making the thickness of the heat radiating fin  16  small, and increasing the heat radiating area. However, when making the thickness of the heat radiating fin  16  small, a sectional area of a heat transfer path becomes small, and heat resistance becomes large. When a heat resistance value becomes large, a transfer of heat to a tip end of the plurality of heat radiating fins  16  is hindered. For this reason, when making the thickness of the plurality of heat radiating fins  16  excessively small, it is not possible to obtain the improvement of the heat radiating property. 
     Meanwhile, since there is a little restriction relating to an external dimension, a wall thickness, or the like, in the protrusion portions  18  and  19 , it is possible to make a sectional area of the heat transfer path large. For this reason, it is possible to use the protrusion portions  18  and  19  as a heat radiating member. That is, it is possible for the protrusion portions  18  and  19  to have a function of not causing an external force to be added to the plurality of heat radiating fins  16  and the terminal cover  17 , and a function of radiating heat together. 
     For this reason, it is possible to improve the heat radiating property when the protrusion portions  18  and  19  are provided. In this case, when making the thickness of the plurality of heat radiating fins  16  large to some extents, it is possible to further improve the heat radiating property. 
     According to a knowledge obtained by the inventors of the exemplary embodiment, it is preferable that the following expressions be satisfied, when the thickness of the heat radiating fin  16  is set to T (mm), the thickness of the protrusion portion  18  is set to T 1  (mm), and the thickness of the protrusion portion  19  is set to T 2  (mm). In addition, T 1  (mm) is an external dimension of the protrusion portion  18  in the thickness direction of the heat radiating fin  16 . T 2  (mm) is an external dimension of the protrusion portion  19  in the thickness direction of the heat radiating fin  16 .
 
 T 1≥2 ×T  
 
 T 2≥2 ×T  
 
     When T (mm), T 1  (mm), and T 2  (mm) satisfy the above described expressions, it is possible to prevent the protrusion portions  18  and  19  from being damaged when a worker grips the protrusion portions  18  and  19 . In addition, it is possible to make a sectional area of the heat transfer path in the protrusion portions  18  and  19  large. For this reason, it is possible to improve a heat radiating property in the protrusion portions  18  and  19 . 
     As illustrated in  FIG. 2 , it is also possible to provide a recessed portion  18   a  which is open to an end face of the protrusion portion  18  (corresponding to an example of first recessed portion), and a recessed portion  19   a  which is open to an end face of the protrusion portion  19  (corresponding to an example of second recessed portion). When the recessed portions  18   a  and  19   a  are provided, it is possible to make the lighting device for vehicle lightweight. In addition, it is possible to suppress a sink of a resin when a heat radiating area is enlarged, or the protrusion portions  18  and  19  are molded. In this case, it is also possible to set to a recessed portion  18   a  which is open to a side face of the protrusion portion  18 , and a recessed portion  19   a  which is open to a side face of the protrusion portion  19 . However, when setting to the recessed portion  18   a  which is open to the side faces of the protrusion portion  18 , and the recessed portion  19   a  which is open to the side faces of the protrusion portion  19 , there is a concern that the sectional area of the heat transfer path may become small. In addition, there is a concern that rigidity of the protrusion portions  18  and  19  may decrease. For this reason, it is preferable to set to the recessed portion  18   a  which is open to the end face of the protrusion portion  18 , and the recessed portion  19   a  which is open to the end face of the protrusion portion  19 . In addition, the number, the size, the depth, the arrangement, and the like, of the recessed portions  18   a  and  19   a  are not limited to the examples, and can be appropriately changed by taking the heat radiating property and the rigidity into consideration. 
       FIGS. 3 to 5  are schematic perspective views which exemplify a heat radiating portion  10   b   1  according to another embodiment. 
     As illustrated in  FIGS. 3 to 5 , the heat radiating portion  10   b   1  includes the flange  14 , the placing portion  15 , the terminal cover  17 , and a protrusion portion  28 . The heat radiating fin  16  is not provided in the heat radiating portion  10   b   1 . 
     The protrusion portion  28  is provided on the face  14   b  of the flange  14 . The protrusion portion  28  can be set to a block shape. The protrusion portion  28  protrudes from the face  14   b  of the flange  14 . An external dimension of the protrusion portion  28  can be set to be appropriately the same as that of the flange  14 . A recessed portion  28   a  which is open to a side face is provided in the protrusion portion  28 . The terminal cover  17  is provided inside the recessed portion  28   a . That is, the terminal cover  17  with low rigidity is surrounded with the protrusion portion  28  with high rigidity. A distance from the face  14   b  of the flange  14  to the end face of the protrusion portion  28  can be set to be approximately the same as the distance from the face  14   b  of the flange  14  to the end face of the terminal cover  17 . For this reason, it is possible to prevent an external force from being added to the terminal cover  17 . 
     The heat radiating portion  10   b   1  also can be formed by integrally molding the flange  14 , the placing portion  15 , the terminal cover  17 , and the protrusion portion  28 , or can be formed by separately forming and joining the elements. In addition, a material of the heat radiating portion  10   b   1  can be set to the same material of the heat radiating portion  10   b.    
     Since the protrusion portion  28  is provided, a worker can easily grip the protrusion portion  28  with high rigidity, when the lighting device for vehicle  1  is mounted on the lighting tool for vehicle  100  by the worker. As a result, it is possible to suppress damage of the terminal cover  17  when the lighting device for vehicle  1  is mounted on the lighting tool for vehicle  100  by the worker. 
     Here, the heat radiating fin  16  is not provided in the heat radiating portion  10   b   1 . However, when setting to the protrusion portion  28  formed in a block shape, it is possible to make the sectional area of the heat transfer path large. According to a knowledge obtained by the inventors of the exemplary embodiment, when adopting the heat radiating portion  10   b   1  provided with the protrusion portion  28  formed in a block shape, it is possible to improve a heat radiating property compared to a heat radiating portion provided only with the plurality of heat radiating fins  16 . 
     As illustrated in  FIG. 3 , it is also possible to provide a recessed portion  28   b  which is open to the end face of the protrusion portion  28 . 
     As illustrated in  FIG. 4 , it is also possible to provide the recessed portion  28   b  on the side face of the protrusion portion  28 . In this case, the recessed portion  28   b  can be set to a through-hole. When the recessed portion is set to the through-hole, it is possible to form an air current which flows inside the protrusion portion  28 . For this reason, it is possible to improve a heat radiating property. 
     As illustrated in  FIG. 5 , the recessed portion  28   b  provided on the side face of the protrusion portion  28  can be set to a groove. When the groove is provided on the side face of the protrusion portion  28 , it is possible to form an air current which flows inside the groove. For this reason, it is possible to improve a heat radiating property. 
     When providing the recessed portion  28   b , it is possible to make the lighting device for vehicle lightweight. In addition, it is possible to suppress a sink of a resin when enlarging the heat radiating area, or molding the protrusion portion  28 . The number, a shape, a depth, an arrangement, or the like, of the recessed portion  28   b  is not limited to examples, and can be appropriately changed by taking a heat radiating property and rigidity into consideration. 
     When adopting the heat radiating portion  10   b   1  according to the embodiment, it is possible to suppress damage of a heat radiating member, and improve a heat radiating property. 
       FIG. 6  is a schematic perspective view which exemplifies a heat radiating portion  10   b   2  according to another embodiment. 
     As illustrated in  FIG. 6 , the heat radiating portion  10   b   2  includes the flange  14 , and a protrusion portion  38 . In addition, similarly to the above described heat radiating portion  10   b , the placing portion  15  is provided in the heat radiating portion  10   b   2 . The heat radiating fin  16  is not provided in the heat radiating portion  10   b   2 . 
     The protrusion portion  38  is provided on the face  14   b  of the flange  14 . The protrusion portion  38  can be set to a block shape. The protrusion portion  38  protrudes from the face  14   b  of the flange  14 . The terminal cover  17  is formed integrally with the protrusion portion  38 . For this reason, a side face of the protrusion portion  38  is provided at a position in which the side face of the terminal cover  17  is provided. An external dimension of the protrusion portion  38  is set to be smaller than that of the flange  14 . In addition, a distance from the face  14   b  of the flange  14  to the end face of the protrusion portion  38  can be set to be approximately the same as the distance from the face  14   b  of the flange  14  to the end face of the terminal cover  17 . Since the terminal cover  17  with low rigidity and the protrusion portion  38  with high rigidity are integrally formed, it is possible to improve resistance to an external force at a portion corresponding to the terminal cover  17 . 
     It is also possible to form the heat radiating portion  10   b   2  by integrally molding the flange  14 , the placing portion  15 , and the protrusion portion  38 , or by separately forming and joining the elements. A material of the heat radiating portion  10   b   2  can be set to be the same as that of the heat radiating portion  10   b.    
     Since the protrusion portion  38  is provided, a worker can easily grip the protrusion portion  38  with high rigidity, when mounting the lighting device for vehicle  1  on the lighting tool for vehicle  100 . As a result, when the lighting device for vehicle  1  is mounted on the lighting tool for vehicle  100  by the worker, it is possible to suppress damage of a portion corresponding to the terminal cover  17 . 
     Here, the heat radiating fin  16  is not provided in the heat radiating portion  10   b   1 . However, when the protrusion portion  38  formed in a block shape is adopted, it is possible to make a sectional area of the heat transfer path large. For this reason, similarly to the above described protrusion portion  28 , it is possible to improve a heat radiating property compared to a heat radiating portion provided only with the plurality of heat radiating fins  16 . 
     In addition, it is also possible to provide a recessed portion  38   a  which is open to an end face of the protrusion portion  38 . Similarly to the above described recessed portion  28   b , it is also possible to provide the recessed portion  38   a  on a side face of the protrusion portion  38 . In this case, the recessed portion  38   a  also can be set to a through-hole. When setting to the through-hole, it is possible to form an air current which flows inside the protrusion portion  38 . For this reason, it is possible to improve a heat radiating property. In addition, the recessed portion  38   a  provided on the side face of the protrusion portion  38  also can be set to a groove. When the groove is provided on the side face of the protrusion portion  38 , it is possible to form an air current which flows inside the groove. For this reason, it is possible to improve a heat radiating property. 
     When the recessed portion  38   a  is provided, it is possible to make the lighting device for vehicle lightweight. In addition, it is possible to suppress a sink of a resin when a heat radiating area is enlarged, or the protrusion portion  38  is molded. The number, a shape, a size, a depth, an arrangement, or the like, of the recessed portion  38   a  is not limited to examples, and can be appropriately changed by taking a heat radiating property and rigidity into consideration. 
     It is possible to provide a recessed portion  38   b  which is open to the side face and the end face of the protrusion portion  38 . A plurality of the recessed portions  38   b  can be provided. The recessed portion  38   b  can be set so as to have a curved face. The shape of the recessed portion  38   b  can be set so as to be fitted to a finger of a person. When the plurality of recessed portions  38   b  are provided, it is easier for a worker to grip the protrusion portion  38 . In addition, it is possible to provide the recessed portion  38   b  also in the above described protrusion portions  18  and  19 , and the protrusion portion  28 . The number, a shape, a size, an arrangement, and the like, of the recessed portion  38   b  are not limited to the examples, and can be appropriately changed. 
     According to the heat radiating portion  10   b   2  in the embodiment, it is possible to suppress damage of a heat radiating member, and to improve a heat radiating property. 
     Lighting Tool for Vehicle 
     Subsequently, the lighting tool for vehicle  100  will be exemplified. 
     Hereinafter, a case in which the lighting tool for vehicle  100  is a front combination light provided in a vehicle will be described, as an example. However, the lighting tool for vehicle  100  is not limited to the front combination light provided in a vehicle. The lighting tool for vehicle  100  may be a lighting tool for vehicle which is provided in a vehicle, a railway vehicle, or the like. 
       FIG. 7  is a schematic and partial sectional view for exemplifying the lighting tool for vehicle  100 . 
     As illustrated in  FIG. 7 , the lighting device for vehicle  1 , a housing  101 , a cover  102 , an optical element portion  103 , a sealing member  104 , and the connector  105  are provided in the lighting tool for vehicle  100 . 
     The housing  101  holds the mounting unit  11 . The housing  101  is formed in a box shape of which one end portion side is open. The housing  101  can be formed of a resin through which light is not transmitted, or the like, for example. An attaching hole  101   a  into which a portion in which the bayonet  12  of the mounting unit  11  is provided is inserted is provided on a base of the housing  101 . A recessed portion into which the bayonet  12  provided in the mounting unit  11  is inserted is provided at the peripheral edge of the attaching hole  101   a . A case in which the attaching hole  101   a  is directly provided in the housing  101  was exemplified; however, an attaching member including the attaching hole  101   a  may be provided in the housing  101 . 
     When attaching the lighting device for vehicle  1  to the lighting tool for vehicle  100 , the portion in which the bayonet  12  of the mounting unit  11  is provided is inserted into the attaching hole  101   a , and the lighting device for vehicle  1  is rotated. Then, the bayonet  12  is held in a joint portion provided at the peripheral edge of the attaching hole  101   a . Such an attaching method is referred to as twist-lock. 
     The cover  102  is provided so as to block the opening of the housing  101 . The cover  102  can be formed of a light-transmitting resin, or the like. It is also possible to set the cover  102  to a cover with a function of lens, or the like. 
     Light output from the lighting device for vehicle  1  is input to the optical element portion  103 . The optical element portion  103  performs reflection, diffusion, light guiding, condensing, a formation of a predetermined light distributing pattern, or the like, of light output from the lighting device for vehicle  1 . 
     For example, the optical element portion  103  exemplified in  FIG. 7  is a reflector. In this case, the optical element portion  103  reflects light output from the lighting device for vehicle  1 , and forms a predetermined light distributing pattern. 
     The sealing member  104  is provided between the flange  14  and the housing  101 . The sealing member  104  can be set to a member formed in an annular shape. The sealing member  104  can be formed of a material with elasticity such as rubber, or a silicone resin. 
     When attaching the lighting device for vehicle  1  to the lighting tool for vehicle  100 , the sealing member  104  is interposed between the flange  14  and the housing  101 . For this reason, an inner space of the housing  101  is enclosed by the sealing member  104 . In addition, the bayonet  12  is pushed to the housing  101  due to an elastic force of the sealing member  104 . For this reason, it is possible to prevent the lighting device for vehicle  1  from escaping from the housing  101 . 
     The connector  105  is fitted to end portions of the plurality of power feeding terminals  31  which are exposed to the inside of the terminal cover  17 . A power supply (not illustrated), or the like, is electrically connected to the connector  105 . For this reason, the power supply (not illustrated), or the like, and the light emitting element  22  are electrically connected when the connector  105  is fitted to the end portion of the power feeding terminal  31 . 
     In addition, a sealing member (not illustrated) is provided in the connector  105 . The sealing member is provided in order to prevent water from entering the inside of the terminal cover  17 . When the connector  105  including the sealing member is mounted on the terminal cover  17 , the inside of the terminal cover  17  is enclosed so as to be watertight. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. Moreover, above-mentioned embodiments can be combined mutually and can be carried out.