Patent Publication Number: US-10317064-B2

Title: Light source unit and vehicle lamp fitting

Description:
This application claims priority from Japanese Patent Applications No. 2015-072897 filed on Mar. 31, 2015 and No. 2015-147768 filed on Jul. 27, 2015, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a technical field of a light source unit including a socket housing and a substrate disposed in the socket housing, and a vehicle lamp including the same. 
     CITATION LIST 
     Patent Document 
     Patent Document 1: JP 2013-25934 (A) 
     BACKGROUND ART 
     For example, there is a vehicle lamp in which a light source unit detachably attached to a lamp outer housing constituted by a lamp body and a cover is provided and a light emitting element such as a light emitting diode is used as a light source of the light source unit. 
     In such a light source unit, a light emitting element serving as a light source and a substrate on which a wiring pattern for supplying current to at least the light emitting element is formed are provided, and the substrate is disposed in a socket housing (e.g, see Patent Document 1). 
     In the light source unit disclosed in Patent Document 1, the socket housing in which the substrate is disposed is attached to a lamp body. A part of a power supply member (connection terminal) for supplying power to the light emitting element or the like is inserted through the substrate, and the portion of the power supply member inserted through the substrate is bonded to the substrate by a conductive metal member (solder). 
     A back side of the substrate is in contact with a heat conducting metal member, and heat generated at the time of emitting light from the light emitting element is released via the heat conducting metal member. 
     DISCLOSURE OF INVENTION 
     Problems to be Solved by Invention 
     However, in the light source unit disclosed in Patent Document 1, a part of the power supply member is inserted through the substrate, the portion of the power supply member inserted through the substrate is bonded to the substrate by the conductive metal member, and the heat conducting metal member is provided only at a position facing the central portion of the substrate in order to avoid interference between the heat conducting metal member and the power supply member. 
     Accordingly, the contact area of the heat conducting metal member with the substrate is so small that sufficient heat-dissipation properties may not be ensured at the time of emitting light from the light emitting element. 
     Therefore, the light source unit and the vehicle lamp of the present invention overcome the above problem and aim to improve the heat-dissipation properties relating to the heat generated at the time of emitting light from the light emitting element. 
     Means for Solving the Problems 
     As a first aspect, a light source unit according to the present invention includes a light emitting element that functions as a light source, a wiring pattern on which the light emitting element is mounted, an electrode pad connected to the wiring pattern, a substrate on which the wiring pattern is formed and the electrode pad is mounted, a power supply body that supplies external power to the electrode pad, and a socket housing which has an engaging portion engaged with a predetermined member and holds the substrate, the light emitting element and the power supply body. The power supply body has a terminal holding portion formed of an insulating resin material, and a connection terminal supported by the terminal holding portion and connected to an external power supply. 
     The connection terminal and the electrode pad are connected to each other by a conduction connecting part. 
     In this way, since the connection terminal of the power supply body is positioned outside the substrate, the heat-dissipation area of the substrate can be increased. 
     As a second aspect, in the light source unit according the present invention described above, it is preferable that one end portion of the connection terminal of the power supply body is located adjacent to the substrate, and at least the portions of the power supply body excluding both end portions are located inside the socket housing. 
     In this way, a distance between the connection terminal and the substrate is shortened, and the power supply body is located so as not to protrude largely from the socket housing. 
     As a third aspect, in the light source unit according the present invention described above, it is preferable that the power supply body is formed by integrally molding the terminal holding portion and the connection terminal, and the power supply body and the socket housing are coupled by being integrally molded. 
     In this way, the power supply body and the socket housing are coupled by being integrally molded after the power supply body is formed by the integral molding. 
     As a fourth aspect, in the light source unit according the present invention described above, it is preferable that a shielding member for shielding at least the conduction connecting part, a positioning hole is formed in one of the socket housing and the shielding member and a positioning pin inserted through the positioning hole is provided in the other, and the shielding member is attached to the socket housing in a state where the positioning pin is inserted through the positioning hole. 
     In this vvay, the conduction connecting part is shielded by the shielding member, and thus, fingers or the like are not inadvertently brought into contact with the conduction connecting part when gripping the light source unit. 
     As a fifth aspect, another light source unit according to the present invention includes a light emitting element that functions as a light source, a wiring pattern on which the light emitting element is mounted, an electrode pad connected to the wiring pattern, a substrate on which the wiring pattern is formed and the electrode pad is mounted, a power supply body that supplies external power to the electrode pad, and a socket housing which has an engaging portion engaged with a predetermined member and holds the substrate, the light emitting element and the power supply body. A placement recess in which the substrate is placed is formed in the socket housing, a part of the connection terminal to be connected to a power supply circuit is positioned in the portion of the placement recess between the substrate and the engaging portion, and the connection terminal and the electrode pad are connected to each other by a conduction connecting part. 
     In this way, since the connection terminal of the power supply body is positioned in the portion of the placement recess outside the substrate, the heat-dissipation area of the substrate can be increased. 
     As a sixth aspect, a vehicle lamp according to the present invention is a vehicle lamp including a light source unit. The light source unit includes a light emitting element that functions as a light source, a wiring pattern on which the light emitting element is mounted, an electrode pad connected to the wiring pattern, a substrate on which the wiring pattern is formed and the electrode pad is mounted, a power supply body that supplies external power to the electrode pad, a socket housing which has an engaging portion engaged with a predetermined member and holds the substrate, the light emitting element and the power supply body. The power supply body has a terminal holding portion formed of an insulating resin material, and a connection terminal supported by the terminal holding portion and connected to an external power supply. The connection terminal and the electrode pad are connected to each other by a conduction connecting part. 
     In this way, in the light source unit, the connection terminal of the power supply body is positioned outside the substrate. Therefore, the heat-dissipation area of the substrate can be increased. 
     As a seventh aspect, another vehicle lamp according to the present invention is a vehicle lamp including a light source unit. The light source unit includes a light emitting element that functions as a light source, a wiring pattern on which the light emitting element is mounted, an electrode pad connected to the wiring pattern, a substrate on which the wiring pattern is formed and the electrode pad is mounted, a power supply body that supplies external power to the electrode pad, and a socket housing which has an engaging portion engaged with a predetermined member and holds the substrate, the light emitting element and the power supply body. A placement recess in which the substrate is placed is formed in the socket housing, a part of the connection terminal to be connected to a power supply circuit is positioned in the portion of the placement recess between the substrate and the engaging portion, and the connection erminal and the electrode pad are connected to each other by a conduction connecting part. 
     In this way, since the connection terminal of the power supply body is positioned in the portion of the placement recess of the light source unit outside the substrate, the heat-dissipation area of the substrate can be increased. 
     Effects of Invention 
     According to the present invention, since the connection terminal of the power supply body is positioned outside the substrate, the heat-dissipation area of the substrate can be increased, and hence, the heat-dissipation properties at the time of emitting light from the light emitting element can be improved. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a sectional view of a vehicle lamp, showing an embodiment of the present invention together with  FIGS. 2 to 16 , 
         FIG. 2  is an exploded perspective view of a light source unit. 
         FIG. 3  is a perspective view of the light source unit. 
         FIG. 4  is a sectional view of the light source unit. 
         FIG. 5  is a front view of the light source unit. 
         FIG. 6  is a rear view of the light source unit. 
         FIG. 7  is a schematic enlarged sectional view showing a state where a lens part is disposed on a sealing part which seals a light emitting element and a conductive wire. 
         FIG. 8  is a schematic enlarged sectional view showing a state where an electrode pad and a connection terminal having a terminal portion linearly formed are connected to each other by a wire. 
         FIG. 9  is a schematic enlarged sectional view showing a state where an electrode pad and a connection terminal having a terminal portion bent are connected to each other by a wire. 
         FIG. 10  is an enlarged sectional view showing a shallow groove portion in a gap formed between an outer peripheral surface of the substrate and an inner peripheral surface of a placement recess. 
         FIG. 11  is an enlarged sectional view showing a deep groove portion in the gap formed between the outer peripheral surface of the substrate and the inner peripheral surface of the placement recess. 
         FIG. 12  is a perspective view showing a state where the light source unit and a shielding member are separated. 
         FIG. 13  is a front view conceptually showing a position of the shallow groove portion in a first modification of a resin-molded part. 
         FIG. 14  is an enlarged sectional view taken along the line XIV-XIV shown in  FIG. 13 . 
         FIG. 15  is a front view conceptually showing the position of the shallow groove portion in the first modification of the resin-molded part. 
         FIG. 16  is a front view conceptually showing a position of the substrate and a positioning portion in a second modification of a resin-molded part. 
     
    
    
     EMBODIMENTS OF INVENTION 
     Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. 
     In the embodiments described below, a light source unit of the present invention is applied to a light source unit used for a combination lamp having a function of a stop lamp and a tail lamp, and a vehicle lamp of the present invention is applied to a vehicle lamp including the light source unit. However, it should be noted that the scope of the present invention is not limited to the light source unit used for the combination lamp having the function of the stop lamp and the tail lamp, and the vehicle lamp including the light source unit. 
     A light source unit of the present invention can be widely applied to a light source unit which is used for various vehicle lamps such as a headlamp, a clearance lamp, a tail lamp, a turn signal lamp, a stop lamp, a day time running lamp, a cornering lamp, a hazard lamp, a position lamp, a back lamp, a fog lamp, or a combination lamp thereof. Further, a vehicle lamp of the present invention can be widely applied to a vehicle lamp including these various light source units. 
     In the following description, a front and rear direction, an up and down direction and a right and left direction are defined in such a manner that an optical axis direction is set as the front and rear direction, and an emission direction of light is set as the rear side. Meanwhile, the front and rear direction, the up and down direction and the right and left direction, which are described below, are defined for convenience of explanation. The practice of the present invention is not limited to these directions. 
     First, a schematic configuration of a vehicle lamp is described (see  FIG. 1 ). 
     A vehicle lamp  1  is respectively attached and arranged at both left and right ends of the front end portion of a vehicle body. 
     The vehicle lamp  1  includes a lamp body  2  having a recess opened rearward and a cover  3  closing a rear opening  2   a  of the lamp body  2 . A lamp outer housing  4  is configured by the lamp body  2  and the cover  3 . An inner space of the lamp outer housing  4  is formed as a lamp chamber  5 . 
     A front end portion of the lamp body  2  is provided as a substantially cylindrical unit mounting portion  6  that penetrates in the front and rear direction. An internal space of the unit mounting portion  6  is formed as a mounting hole  6   a . At an inner peripheral surface of the unit mounting portion  6 , engaging protrusions  7 ,  7 , . . . protruding inwardly are provided so as to be spaced apart from each other in a circumferential direction. 
     Subsequently, a structure of a light source unit  8 , which is attached to the lamp body  2 , is described (see  FIGS. 2 to 6 ). 
     The light source unit  8  is detachably attached to the unit mounting portion  6  of the lamp body  2 . The light source unit  8  includes a socket housing  9 , a power supply body  10 , and a light emitting module  11  (see  FIGS. 2 to 6 ). 
     The socket housing  9  is formed by integrally molding a resin-molded part  12  and a heat-dissipation plate  13 . As the integral molding, for example, a so-called insert molding is used in which a molten resin (resin material) is filled in a state where a metallic material is retained in a cavity of a mold, and a molded product is integrally formed by the metallic material and the resin material. 
     The resin-molded part  12  has excellent thermal conductivity and is formed of, for example, a resin material which contains carbon or the like. The resin-molded part  12  also has conductivity. It is preferable that a heat conduction coefficient of the resin-molded part  12  is in a range of 1 W/(mK) to 30 W/(mK), and the thermal conductivity thereof is lower than that of the heat-dissipation plate  13  and higher than that of a terminal holding portion ( 21 ) (to be described later). The resin-molded part  12  has a disc-shaped base surface portion  14  oriented in the front and rear direction, a protrusion-shaped portion  15  protruding rearward from the center of the base surface portion  14 , first heat-dissipation fins  16 ,  16 , . . . protruding forward from the base surface portion  14 , second heat-dissipation fins  17 ,  17  protruding forward from the base surface portion  14 , and a connector connection portion  18  protruding forward from the base surface portion  14 . 
     The protrusion-shaped portion  15  includes a substrate placement portion  19  having a circular outer shape and engaging portions  20 ,  20 , . . . provided on an outer peripheral surface of the substrate placement portion  19 . 
     The substrate placement portion  19  is formed with a placement recess  19   a  opening rearward. The placement recess  19   a  has a substantially rectangular shape and is slightly greater than an outer shape of the light emitting module  11 . The engaging portions  20 ,  20 , . . . are provided so as to be spaced apart from each other in the circumferential direction. The engaging portions  20 ,  20 , . . . are located at a rear end portion of the substrate placement portion  19 . 
     The first heat-dissipation fins  16 ,  16 , . . . are provided side by side at equal intervals in the right and left direction, for example, and protrude from an upper half in the portion other than both left and right ends of the base surface portion  14  (see  FIG. 6 ). 
     The second heat-dissipation fins  17 ,  17  are respectively disposed at both sides of the first heat-dissipation fins  16 ,  16 , . . . in the right and left direction and protrude from both left and right ends of the base surface portion  14 . A thickness in the right and left direction of the second heat-dissipation fins  17 ,  17  is thicker than a thickness in the right and left direction of the first heat-dissipation fins  16 ,  16 , . . . . 
     The connector connection portion  18  has a cylindrical shape whose axial direction is the front and rear direction, and is disposed below the first heat-dissipation fin  16 ,  16 , . . . . 
     The heat-dissipation plate  13  is formed in a predetermined shape by a plate-like metallic material such as aluminum having high thermal conductivity (see  FIGS. 2 and 4 ). The heat-dissipation plate  13  includes a first heat-dissipation portion  13   a , second heat-dissipation portions  13   b ,  13   b , third heat-dissipation portions  13   c ,  13   c , and fourth heat-dissipation portions  13   d ,  13   d . 
     The first heat-dissipation portion  13   a  and the fourth heat-dissipation portions  13   d ,  13   d  are respectively formed in a substantially rectangular shape oriented in the front and rear direction. The second heat-dissipation portions  13   h ,  13   b  and the third heat-dissipation portions  13   c ,  13   c  are respectively formed in a substantially rectangular shape oriented in the right and left direction. Rear ends of the third heat-dissipation portions  13   c ,  13   c  are respectively continuous with both left and right ends of the first heat-dissipation portion  13   a . Inner ends of the fourth heat-dissipation portions  13   d ,  13   d  are respectively continuous with front ends of the third heat-dissipation portions  13   c ,  13   c , and outer ends thereof are respectively continuous with rear ends of the second heat-dissipation portions  13   b ,  13   b . Therefore, the third heat-dissipation portions  13   c ,  13   c  are respectively formed by being bent in a direction perpendicular to the first heat-dissipation portion  13   a . The fourth heat-dissipation portions  13   d ,  13   d  are respectively formed by being bent in a direction perpendicular to the third heat-dissipation portions  13   c ,  13   c . The second heat-dissipation portions  13   b ,  13   b  are respectively formed by being bent in a direction perpendicular to the fourth heat-dissipation portions  13   d ,  13   d.    
     The heat-dissipation plate  13  is configured such that the first heat-dissipation portion  13   a  is disposed in the placement recess  19   a  of the substrate placement portion  19  of the resin-molded part  12  and is exposed to the resin-molded part  12  (see  FIG. 4 ). The heat-dissipation plate  13  is configured such that the second heat-dissipation portions  13   b ,  13   b  are respectively disposed on the inside of the second heat-dissipation fins  17 ,  17 , the third heat-dissipation portions  13   c ,  13   c  are disposed on the inside of the substrate placement portion  19 , and the fourth heat-dissipation portions  13   d ,  13   d  are disposed on the inside of the base surface portion  14 . 
     An insertion and placement hole (not shown) is formed at a position up to the base surface portion  14  from the substrate placement portion  19  of the resin-molded part  12 . The insertion and placement hole communicates with the interior of the placement recess  19   a  and the connector coupling portion  18 . 
     The power supply body  10  includes a terminal holding portion  21  formed of an insulating resin material, and connection terminals  22 ,  22 ,  22  which are held in the terminal holding portion  21  and connected to a power supply circuit (external power; not shown) (see  FIG. 2 ). 
     The terminal holding portion  21  has a flat shape which extends in the front and rear direction and has a thin thickness in the up and down direction. 
     The connection terminals  22 ,  22 ,  22  are for lied of a metallic material and disposed side by side in the right and left direction in the interior of the terminal holding portion  21  except for a part thereof. Each connection terminal  22  has a terminal portion  23  extending in the front and rear direction, and retaining protrusions  24 ,  24  protruding in opposite directions from a rear end position of the terminal portion  23 . A front end portion of each terminal portion  23  is provided as a connector connection portion  23   a , and a rear end portion thereof is provided as a wire connection portion  23   b . At least a portion of the surface of the wire connection portion  23   b  is subjected to surface treatment by nickel or gold or the like, for example. 
     Each connection terminal  22  is configured such that the connector connection portion  23   a  protrudes forward from the terminal holding portion  21  and the wire connection portion  23   b  protrudes rearward from the terminal holding portion  21 . Since the retaining protrusions  24 ,  24  are positioned at the inside of the terminal holding portion  21 , the connection terminal  22  is prevented from being detached from the terminal holding portion  21  in the front and rear direction. 
     The power supply body  10  is integrally formed by an insert molding of the terminal holding portion  21  and the connection terminals  22 ,  22 ,  22 , for example. The power supply body  10  is configured such that the portion other than the connector connection portions  23   a ,  23   a ,  23   a  and the wire connection portions  23   b ,  23   b ,  23   b  is inserted into the insertion and placement hole formed in the resin-molded part  12 , the connector connection portions  23   a ,  23   a ,  23   a  are disposed at the inside of the connector connection portion  18  (see  FIG. 6 ), and the wire connection portions  23   b ,  23   b ,  23   b  are disposed in the placement recess  19   a  (see  FIG. 3 ). 
     For example, in the state of being formed by an insert molding, the power supply body  10  is positioned in a cavity of a mold, molten resin for forming the resin-molded part  12  is filled into the cavity, and the power supply body  10  is formed integrally with the socket housing  9  by an insert molding, for example. 
     In this manner, the power supply body  10  is formed by integrally molding the terminal holding portion  21  and the connection terminals  22 ,  22 ,  22 , and the power supply body  10  and the socket housing  9  are coupled by being integrally molded. 
     Therefore, the power supply body  10  is foiiEied by the integral molding, and then, the power supply body  10  and the socket housing  9  are integrally molded, so that good positional accuracy of the connection terminals  22 ,  22 ,  22  to the terminal holding portion  21  and good positional accuracy of the power supply body  10  to the socket housing  9  can be ensured. Further, an operation of coupling the power supply body  10  and the socket housing  9  is not necessary, so that workability can be improved. 
     The light emitting module  11  includes a substrate  25  having a substantially rectangular shape oriented in the front and rear direction, light emitting elements  26 ,  26 , . . . mounted on the substrate  25 , and various control elements  27 ,  27 , . . . mounted on the substrate  25  (see  FIGS. 2 to 5 ). 
     The substrate  25  is, for example, a ceramic substrate. A wiring pattern for supplying current to the light emitting elements  26 ,  26 , . . . is formed in the substrate  25 . The size of the substrate  25  is slightly larger than that of the first heat-dissipation portion  13   a  of the heat-dissipation plate  13 . 
     For example, five light emitting elements  26 ,  26 , . . . are mounted on the center of the substrate  25 . Light emitting diodes (LEDs) are used as the light emitting elements  26 ,  26 , . . . . The light emitting elements  26 ,  26 , . . . are configured such that four light emitting elements  26 ,  26 , . . . are mounted around one light emitting element  26  in the state of being spaced apart from each other at equal intervals in the circumferential direction. The center light emitting element  26  serves as a light source for a tail lamp, for example, and four surrounding light emitting elements  26 ,  26 , . . . serve as a light source for a stop lamp, for example. The light emitting elements  26 ,  26 , . . . are respectively connected to the wiring patterns by conductive wires  28 ,  28 , . . . (see  FIG. 7 ). 
     The connection terminals  22 ,  22 ,  22  are provided as a power supply terminal for a tail lamp, a power supply terminal for a stop lamp, and a power supply terminal for an earth, respectively. 
     Further, the number and function of the light emitting element  26  mounted on the substrate  25  can be arbitrarily set, depending on the type and the required brightness or the like of the vehicle lamp  1 . 
     For example, diodes, capacitors or resistors or the like are used as the control elements  27 ,  27 , . . . . The control elements  27 ,  27 , . . . are mounted at positions of the light emitting module  11  on the outside of the light emitting elements  26 ,  26 , . . . and are connected to the wiring patterns, respectively. 
     A rear surface of the substrate  25  is adhered to the surface of the first heat-dissipation portion  13   a  of the heat-dissipation plate  13  by an adhesive  30  (see  FIG. 4 ). A thermally conductive adhesive is used as the adhesive  30 . 
     At a lower end portion of the substrate  25 , electrode pads  29 ,  29 ,  29  connected to the wiring patterns are formed side by side in the right and left direction (see  FIG. 3 ). 
     The electrode pads  29 ,  29 ,  29  are located in the vicinity of the wire connection portions  23   b ,  23   b ,  23   b  of the connection terminals  22 ,  22 ,  22 , respectively. 
     For example, the electrode pads  29 ,  29 ,  29  are respectively connected, through ultrasonic welding or soldering, to the wire connection portions  23   b ,  23   b ,  23   b  of the connection terminals  22 ,  22 ,  22  by wires  31 ,  31 ,  31  formed of aluminum or the like and serving as a conduction connecting part. The connection between the wire connection portion  23   b  and the wire  31  is performed at the portion of the wire connection portion  23   b , which is subjected to the surface treatment by nickel or gold or the like. Meanwhile, the connection between the electrode pads  29 ,  29 ,  29  and the connection terminals  22 ,  22 ,  22  may be performed by a conduction connecting part other than the wires  31 ,  31 ,  31 . 
     Further, as shown in  FIG. 8 , the connection terminal  22  may be configured such that the terminal portion  23  is linearly formed and a rear end surface of the terminal portion  23  is joined to the wire  31 , or, as shown in  FIG. 9 , the connection terminal  22  may be configured such that a rear end portion of the terminal portion  23  is bent by 90° and a peripheral surface of the terminal portion  23  is joined to the wire  31 . 
     A frame body  32  is attached to the portion of the substrate  25  between the light emitting elements  26 ,  26 , . . . and the control elements  27 ,  27 , . . . (see  FIGS. 3, 4 and 7 ). The frame body  32  is formed in a substantially annular shape by a resin material. The frame body  32  is disposed at a position to surround the light emitting elements  26 ,  26 , . . . and the conductive wires  28 ,  28 , . . . . 
     A sealing part  33  is applied inside the frame body  32 . The light emitting elements  26 ,  26 , . . . and the conductive wires  28 ,  28 , . . . are sealed by the sealing part  33  (see  FIG. 7 ). The sealing part  33  is formed in such a way that liquid sealing resin is filled (injected) into the frame body  32  and then cured. In this way, the sealing part  33  seals the light emitting elements  26 ,  26 , . . . and the conductive wires  28 ,  28 , . . . . Therefore, the frame body  32  has a function of determining the sealing part  33  into a predetermined shape by preventing the seal sin from unnecessarily flowing toward the control elements  27 ,  27 , . . . . 
     The refractive index of the sealing part  33  has an intermediate value of the refractive index of the light emitting elements  26 ,  26 , . . . and the refractive index of air. Since the light emitting elements  26 ,  26 , . . . are sealed by the sealing part  33 , a difference between the refractive index of the light emitting elements  26 ,  26 , . . . and the refractive index of air is alleviated. Therefore, the emission efficiency of light from the light emitting elements  26 ,  26 , . . . to the outside is improved. 
     A lens part  34  is disposed on the sealing part  33 . The lens part  34  is formed of a predetermined molding resin and has a hemispherical shape which is convex rearward. The lens part  34  is formed in such a rummer that, for example, predetermined liquid molding resin is filled and cured on the sealing part  33  before curing or after curing on the inside of the frame body  32 . Therefore, the frame body  32  also has a function of determining the lens part  34  into a predetermined shape by preventing the molding resin for forming the lens part  34  from unnecessarily flowing toward the control elements  27 ,  27 , . . . . 
     The lens part  34  is for ued in such a manner that the molding resin is filled and cured on the sealing part  33 . Therefore, the frame body  32  also has a function of determining the lens part  34  into a predetermined shape by preventing the molding resin for forming the lens part  34  front unnecessarily flowing toward the control elements  27 ,  27 , . . . . 
     Further, the refractive index of the lens part  34  has an intermediate value of the refractive index of the light emitting element  26  and the refractive index of air. Since the light emitted from the light emitting elements  26 ,  26 , . . . is less likely to be totally reflected at the interface of the sealing part  33  and the lens part  34 , it is possible to improve the emission efficiency of light from the light emitting elements  26 ,  26 , . . . to the outside. 
     Furthermore, since the frame body  32  is provided, the sealing resin or molding resin is formed in a certain shape even in the case where the injection position of the sealing resin or molding resin is deviated from a predetermined position when the sealing resin or molding resin is injected to the inside of the frame body  32 . Therefore, it is possible to improve the molding accuracy of the sealing resin or molding resin. 
     The molding resin has viscosity higher than that of the sealing resin and has flowability lower than that of the sealing resin. The viscosity of the molding resin is equal to or greater than 40 Pa·s (pascal·second), for example, and the viscosity of the sealing resin is in the range of 5 to 15 Pa·s (pascal·second), for example. 
     When the viscosity of the molding resin is set to be equal to or greater than 40 Pa·s, the molding resin does not flow more than necessary at the time of being injected onto the sealing resin. Therefore, the shape of the lens part  34  is likely to be formed in a desired shape. 
     On the other hand, when the viscosity of the sealing resin is set to the range of 5 to 15 Pa·s, the sealing resin is flowing in a desired state at the time of being injected onto the substrate  25 . Therefore, it is easy to maintain a planar shape and it is possible to secure good formability. Further, when the viscosity of the sealing resin is set to the range of 5 to 15 Pa·s, the load on the conductive wires  28 ,  28 , . . . becomes small when the sealing resin is injected onto the substrate  25 . Therefore, it is possible to suppress the occurrence of disconnection or the like of the conductive wires  28 ,  28 , . . . . 
     Meanwhile, when the sealing resin is injected onto the substrate  25 , the sealing resin is injected to the inside of the frame body  32  and the shape of the sealing resin (the sealing part  33 ) is determined by the frame body  32 . Therefore, the viscosity of the sealing resin may be less than 5 Pa·s. 
     Further, there is a case that the lens part  34  is formed by a mold and then disposed on the sealing part  33 . However, in this case, since the lens part  34  is formed into a predetermined shape by the mold, the molding resin having viscosity less than 40 Pa·s may be used. Meanwhile, at room temperature (25° C.), the lens part (after curing)  34  has a higher elastic modulus than the sealing part  33  (after curing). Preferably, the elastic modulus of the sealing part  33  is less than 1 MPa and the elastic modulus of the lens part  34  is equal to or greater than 1 Mpa. 
     In the state where the lens part  34  is disposed, the light emitting elements  26 ,  26 , . . . and the conductive wires  28 ,  28 , . . . are covered by the lens part  34  in a state of being sealed by the sealing part  33 . 
     Meanwhile, an example where the frame body  32  is formed of a resin material has been illustrated in the above description. However, the frame body  32  may be formed of a metallic material. Further, the frame body  32  may be formed of a resin material and the surface thereof may be subjected to processing such as metal deposition. Furthermore, the frame body  32  may be formed of a white resin. By configuring the frame body  32  in this structure, the frame body  32  can serve as a reflector to reflect a portion of light emitted from the light emitting elements  26 ,  26 , . . . . 
     An annular gasket  36  formed of, for example, a rubber material or a resin material is externally fitted and attached to the protrusion-shaped portion  15  of the light source unit  8  configured as described above (see  FIGS. 1 and 4 ). The gasket  36  is formed of a resin material or a rubber material. In the state where the gasket  36  is attached to the light source unit  8 , the protrusion-shaped portion  15  is inserted to the unit mounting portion  6  of the lamp body  2  from the front and is rotated in the circumferential direction. In this way, the engaging portions  20 ,  20 , . . . are respectively engaged with the engaging protrusions  7 ,  7 , . . . from the rear (see  FIG. 1 ). At this time, the engaging protrusions  7 ,  7 , . . . are clamped in the engaging portions  20 ,  20 , . . . and the gasket  36 , and hence, the light source unit  8  is attached to the lamp body  2 . in the state where the light source unit  8  is attached to the lamp body  2 , the unit mounting portion  6  is closed by the gasket, and hence, foreign matters such as moisture are prevented from entering the lamp chamber  5  through the unit mounting portion  6  from the outside. 
     On the contrary, when the light source unit  8  is rotated in a direction opposite to the above direction along the circumferential direction, the engagement of the engaging portions  20 ,  20 , . . . to the engaging protrusions  7 ,  7 , . . . is released, and hence, the protrusion-shaped portion  15  can be pulled from the unit mounting portion  6 . In this way, the light source unit  8  can be detached from the lamp body  2 . 
     When current is supplied to the wiring pattern through the connection terminals  22 ,  22 ,  22  from the power supply circuit in the state where the light source unit  8  is attached to the lamp body  2 , light is emitted from at least one light emitting element  26 . At this time, when the vehicle lamp  1  serves as a tail lamp, light is emitted from one light emitting element  26  located at the center. Further, when the vehicle lamp  1  serves as a stop lamp, light is emitted from four light emitting elements  26 ,  26 , . . . other than the one located at the center. 
     The light emitted from the light emitting element  26  is transmitted through the sealing part  33  and the lens part  34 , and is irradiated to the outside through the cover  3 . At this time, the irradiation direction of the light is controlled by the lens part  34 , so that the light is irradiated to the outside toward a predetermined direction. At this time, when the frame body  32  serves as a reflector, a portion of the light emitted from the light emitting element  26  is irradiated to the outside by being reflected in the frame body  32 . 
     At the time of emitting light from the light emitting element  26 , heat is generated in the light emitting module  11 . However, the heat generated is transmitted to the first heat-dissipation portion  13   a  through the adhesive  30  having excellent thermal conductivity, and is transmitted to the heat-dissipation plate  13  and the resin-molded part  12 . The heat, which is transmitted to the heat-dissipation plate  13  and the resin-molded part  12 , is mainly dissipated to the outside from the first heat-dissipation fins  16 ,  16 , . . . and the second heat-dissipation fins  17 ,  17 . 
     As described above, in the light source unit  8 , the electrode pads  29 ,  29 ,  29  are provided in the light emitting module  11 , the power supply body  10  is disposed outside the light emitting module  11 , and the electrode pads  29 ,  29 ,  29  and the connection terminals  22 ,  22 ,  22  are connected to each other by the wires  31 ,  31 ,  31 , respectively. 
     In such a configuration, for example, the electrode pads  29 ,  29 ,  29 , the connection terminals  22 ,  22 ,  22 , and the wires  31 ,  31 ,  31  may be sealed with resin. 
     As the wires  31 ,  31 ,  31  are sealed with the resin, for example, when the light source unit  8  is attached to or detached from the lamp body  2 , fingers or the like are not inadvertently brought into contact with the wires  31 ,  31 ,  31 . Therefore, the disconnection of the wires  31 ,  31 ,  31  or the detachment of the wires  31 ,  31 ,  31  from the electrode pads  29 ,  29 ,  29  and the connection terminals  22 ,  22 ,  22  can be prevented. 
     Further, as described above, the placement recess  19   a  formed in the substrate placement portion  19  of the socket housing  9  is slightly larger than the outer shape of the substrate  25  of the light emitting module  11 . Therefore, in the state where the light emitting module  11  is disposed in the placement recess  19   a , a gap  35  is formed between an outer peripheral surface of the substrate  25  and an inner peripheral surface of the placement recess  19   a  (see  FIG. 5 ). As described above, the size of the substrate  25  is slightly larger than that of the first heat-dissipation portion  13   a  of the heat-dissipation plate  13 . Therefore, when the substrate  25  is attached to the first heat-dissipation portion  13   a  of the heat-dissipation plate  13  by the adhesive  30 , a part of the adhesive  30  is protruded to the outer peripheral side of the first heat-dissipation portion  13   a  and the protruded adhesive  30  is filled in the gap  35 . 
     The gap  35  is configured such that, out of the four linear groove portions around the substrate  25 , one linear portion positioned on the front side of the wires  31 ,  31 ,  31  is formed as a shallow groove portion  35   a  (see  FIG. 10 ) and the other thee linear portions are formed as deep groove portion  35   b ,  35   b ,  35   b , respectively (see  FIG. 11 ). The shallow groove portion  35   a  is shallower than the deep groove portions  35   b ,  35   b ,  35   b , and the bottom surface forming the shallow groove portion  35   a  is provided to have substantially the same height as a surface of the first heat-dissipation portion  13   a . Therefore, a surface  30   a  of the adhesive  30  protruding when attaching the substrate  25  to the first heat-dissipation portion  13   a  is present at a position closer to the substrate  25  in the shallow groove portion  35   a  than the deep groove portion  35   b  (see  FIGS. 10 and 11 ). 
     In this manner, the portion of the gap  35  positioned on the front side of the wires  31 ,  31 ,  31  is formed as the shallow groove portion  35   a  and, in the shallow groove portion  35   a , the portion of the rear surface (front surface) of the substrate  25  is filled with the adhesive  30 . Therefore, when the wires  31 ,  31 ,  31  are connected to the electrode pads  29 ,  29 ,  29  by ultrasonic bonding, appropriate ultrasonic wave can be propagated to a bonding portion between the wires  31 ,  31 ,  31  and the electrode pads  29 ,  29 ,  29 . Thus, a sufficient amount of ultrasonic wave is propagated to the bonding portions between the wires  31 ,  31 ,  31  and the electrode pads  29 ,  29 ,  29 . A strong bonding state of the wires  31 ,  31 ,  31  to the electrode pads  29 ,  29 ,  29  can be ensured. 
     Furthermore, the electrode pads  29 ,  29 ,  29 , the connection terminals  22 ,  22 ,  22  and the wires  31 ,  31 ,  31  may be configured to be covered by a shielding member  37  (see  FIG. 12 ). When the shielding member  37  is used, positioning holes  15   a ,  15   a  are formed and locking protrusions  15   b ,  15   b  are provided in the protrusion-shaped portion  15  of the socket housing  9 , for example. In the shielding member  37 , positioning pins  37   a ,  37   a  are provided and locking hole  37   b ,  37   b  are formed. 
     The shielding member  37  is attached to the socket housing in such a manner that the positioning pins  37   a ,  37   a  are positioned relative to the socket housing  9  by being respectively inserted through the positioning holes  15   a ,  15   a  and the locking protrusions  15   b ,  15   b  are respectively locked to the locking holes  37   b ,  37   b.    
     In this way, the shielding member  37  shielding at least the wires  31 ,  31 ,  31  is provided and the positioning pins  37   a ,  37   a  are respectively inserted through the positioning holes  15   a ,  15   a , so that the shielding member  37  is attached to the socket housing  9 . 
     Therefore, the wires  31 ,  31 ,  31  are reliably shielded by the shielding member  37  and, for example, when the light source unit  8  is attached to or detached from the lamp body  2 , fingers or the like are not inadvertently brought into contact with the wires  31 ,  31 ,  31 , so that the disconnection of the wires  31 ,  31 ,  31  or the detachment of the wires  31 ,  31 ,  31  from the electrode pads  29 ,  29 ,  29  and the connection terminals  22 ,  22 ,  22  can be prevented. 
     Further, for example, the shielding member  37  may be formed in a shape or size allowing it to serve as a shade for shielding a part of light emitted from the light emitting elements  26 ,  26 , . . . . As the shielding member  37  is also used as the shade, the functionality of the light source unit  8  can be improved and a desired light distribution pattern can be formed without increasing the number of parts. 
     In the light source unit  8 , the power supply body  10  includes the terminal holding portion  21  formed of an insulating resin material, and the connection terminals  22 ,  22 ,  22  held in the terminal holding portion  21 . The power supply body  10  is connected to the socket housing  9 , and the connection terminals  22 ,  22 ,  22  and the electrode pads  29 ,  29 ,  29  provided in the light emitting module  11  are connected to each other by the wires  31 ,  31 ,  31 . 
     Therefore, there is no need to provide a space for inserting the connection terminals  22 ,  22 ,  22  in the light emitting module  11 . Further, since the connection terminals  22 ,  22 ,  22  are positioned outside the light emitting module  11 , the connection terminals  22 ,  22 ,  22  do not interfere with the first heat-dissipation portion  13   a  of the heat-dissipation plate  13 , and thus, the contact area between the substrate  25  and the heat-dissipation plate  13  can be increased, thereby increasing the heat-dissipation area. As a result, the heat-dissipation properties at the time of emitting light from the light emitting elements  26 ,  26 , . . . can be improved. 
     Further, one end portions of the connection terminals  22 ,  22 ,  22  of the power supply body  10  are located adjacent to the substrate  25 , and at least the portions of the power supply body  10  excluding both end portions are located inside the socket housing  9 . 
     Therefore, since the lengths of the wires  31 ,  31 ,  31  are shortened, and the power supply body  10  is located so as not to protrude largely from the socket housing  9 , the manufacturing cost of the light source unit  8  can be reduced and the size thereof can be reduced. 
     Furthermore, the placement recess  19   a  in which the light emitting module  11  is placed is formed in the socket housing  9 . The wire connecting portions  23   b ,  23   b ,  23   b  of the connection terminals  22 ,  22 ,  22  are positioned at the portions of the placement recess  19   a  between the light emitting module  11  and the engaging portion  20 . The connection terminals  22 ,  22 ,  22  and the electrode pads  29 ,  29 ,  29  are connected to each other by the wires  31 ,  31 ,  31 . 
     Therefore, since the connection terminals  22 ,  22 ,  22  do not interfere with the first heat-dissipation portion  13   a  of the heat-dissipation plate  13 , the contact area between the substrate  25  and the heat-dissipation plate  13  can be increased, thereby increasing the heat-dissipation area. As a result, the heat-dissipation properties at the time of emitting light from the light emitting elements  26 ,  26 , . . . can be further improved. 
     Further, since the light emitting module  11  and the wire connecting portions  23   b ,  23   b ,  23   b  of the connection terminals  22 ,  22 ,  22  are positioned in the placement recess  19   a , fingers or the like are not inadvertently brought into contact with the wires  31 ,  31 ,  31  connecting the wire connecting portions  23   b ,  23   b ,  23   b  and the electrode pads  29 ,  29 ,  29 , and thus, the disconnection of the wires  31 ,  31 ,  31  or the detachment of the wires  31 ,  31 ,  31  from the electrode pads  29 ,  29 ,  29  and the connection terminals  22 ,  22 ,  22  can be prevented. 
     Meanwhile, for a lighting used outdoors like the vehicle lamp  1 , when ambient light such as sunlight is incident thereon in a state where the light emitting elements  26 ,  26 , . . . are lit, the visibility from the outside may be deteriorated, and thus, it may be difficult to recognize the lighting state thereof. 
     Thus, it is desirable that the light emission luminance of the light emitting elements  26 ,  26 , . . . are changed with respect to the surrounding brightness. As such a configuration, for example, a configuration can be used in which a sensor for detecting the light intensity of external light is provided in the light emitting module  11  or in a portion other than the light emitting module  11 , and the light emission luminance of the light emitting elements  26 ,  26 , . . . are changed in accordance with the detection results of the sensor. 
     By using such a configuration, for example, when the surroundings are dark, a control of decreasing the light emission luminance of the light emitting elements  26 ,  26 , . . . performed. Further, when external light such as sunlight is incident on the vehicle lamp  1 , a control of increasing the light emission luminance is performed to increase the visibility from the outside. 
     Next, a first modification of a resin-molded part will be described with reference to  FIGS. 13 to 15 . Here,  FIGS. 13 and 15  are front views schematically showing the light source unit  8 . 
     In a resin-molded part  12 A according to a first modification, the shallow groove portions  35   a ,  35   a , . . . are formed in respective central portions of the four linear portions in the gap  35 , and other portions are formed as the deep groove portions  35   b ,  35   b , . . . (see  FIG. 13 ). 
     In the above configuration, when the substrate  25  is attached to the rear surface of the first heat-dissipation portion  13   a  by the adhesive  30 , a part of the adhesive  30  is protruded to the rear surface of the shallow groove portions  35   a ,  35   a , . . . , and most of the adhesive  30  flows into the deep groove portions  35   b ,  35   b , . . . , as shown in  FIG. 14 . 
     Therefore, the adhesive  30  protruding into the shallow groove portion  35   a ,  35   a , . . . can be visually confirmed. Further, it can be confirmed that the substrate  25  is adhered to the first heat-dissipation portion  13   a , and the adhesive  30  is uniformly spread between the substrate  25  and the first heat-dissipation portion  13   a . Further, the shallow groove portions  35   a ,  35   a , . . . thicker than the deep groove portions  35   b ,  35   b , . . . in the front and rear direction are respectively formed between the deep groove portions  35   b ,  35   b , . . . in the gap  35 . In this way, the rigidity of the resin-molded part  12 A is increased in the entire peripheries of the substrate  25 , so that the intensity of the resin-molded part  12 A can be also increased. 
     Meanwhile, the position of the rear surface of the shallow groove portion  35   a  may be any position, as long as the adhesive  30  can protrude to the rear surface of the shallow groove portion  35   a . The position of the rear surface of the shallow groove portion  35   a  may be the same position as the rear surface of the first heat-dissipation portion  13   a  or may be on the front side of the rear surface of the first heat-dissipation portion  13   a.    
     Further, in the resin-molded part  12 A, it is desirable that one shallow groove portion  35   a  is positioned on the front side of the wires  31 ,  31 ,  31  in the gap  35 . 
     In this way, since a sufficient amount of ultrasonic wave is propagated to the bonding portions between the wires  31 ,  31 ,  31  and the electrode pads  29 ,  29 ,  29 , a strong bonding state of the wires  31 ,  31 ,  31  to the electrode pads  29 ,  29 ,  29  can be also ensured, in addition to being able to visually confirm the adhesive  30 . 
     Meanwhile, as shown in  FIG. 15 , the shallow groove portions  35   a ,  35   a , may be formed at four corners of the gap  35 . Further, the shallow groove portion  35   a  is not limited to this position but may be formed in at least one location of the gap  35 . 
     Also in this case, similar to the case where the shallow groove portion  35   a  is positioned at the central portion of the linear portion (see  FIGS. 13 and 14 ), the adhesive  30  protruding into the shallow groove portion  35   a  can he visually confirmed. Further, it can be confirmed that the substrate  25  is adhered to the first heat-dissipation portion  13   a , and the adhesive  30  is uniformly spread between the substrate  25  and the first heat-dissipation portion  13   a.    
     Next, a second modification of a resin-molded part will be described with reference to  FIG. 16 . Here,  FIG. 16  is a front view schematically showing the light source unit  8 . 
     In a resin-molded part  12 B according to a second modification, positioning portions  19   b ,  19   b  are provided in at least two adjacent corners among four corners of the placement recess  19   a  of the substrate placement portion  19 . The rear surface of the positioning portion  19   b  is located on the rear side of the front surface (hack surface) of the substrate  25 , and the inner side surface of the positioning portion  19   b  is formed as a slope inclined, for example, by 45 degrees with respect to the up and down direction and the right and left direction. 
     The substrate  25  has, for example, chamfered portions  25   a ,  25   a  at two adjacent corners. The chamfered portions  25   a ,  25   a  are chamfered at the same angle as the positioning portions  19   b ,  19   b.    
     In the above configuration, when the substrate  25  is placed on the rear surface of the first heat-dissipation portion  13   a , the chamfered portions  25   a  are abutted against the inner side surface of the positioning portions  19   b , so that the chamfered portions  25   a  make surface contact with the positioning portions  19   b . In this way, the substrate  25  is positioned with respect to the substrate placement portion  19 , and rotation of the substrate  25  in the vertical plane is prevented. 
     Therefore, since the position of the substrate  25  with respect to the substrate placement portion  19  is determined only by abutting the chamfered portions  25   a ,  25   a  against the inner side surface of the positioning portions  19   b ,  19   b , respectively, the positioning of the substrate  25  with respect to the substrate placement portion  19  can be easily performed. Further, since the high positional accuracy of the substrate  25  with respect to the resin-molded part  12 B is ensured, the high positional accuracy of the light emitting elements  26 ,  26 , . . . with respect to the lamp body  2  can be easily ensured. 
     Meanwhile, the positioning portion  19   b  may be provided at three or four corners among the four corners of the placement recess  19   a . In this case, three or four chamfered portions  25   a  may be formed in the substrate  25 , thereby positioning the substrate  25  with respect to the substrate placement portion  19 . 
     However, as described above, since the positioning can be performed by providing the positioning portions  19   b ,  19   b  at two adjacent positions, it is only necessary to ensure good machining accuracy of two positioning portions  19   b ,  19   b  and two chamfered portions  25   a ,  25   a . Therefore, the number of parts requiring good machining accuracy can be small, and thus, the manufacturing cost of the resin-molded part  12 B can be reduced. 
     REFERENCE NUMERALS LIST 
       1  . . . Vehicle Lamp,  8  . . . Light Source Unit,  9  . . . Socket Housing,  10  . . . Power Supply Body,  11  . . . Light Emitting Module,  15   a . . .  Positioning Hole,  20  . . . Engaging Portion,  21  . . . Terminal Holding Portion,  22  . . . Connection terminal,  25  . . . Substrate,  26  . . . Light Emitting Element,  29  . . . Electrode Pad,  31  . . . Wire (Conductive Connecting Portion),  37  . . . Shielding Member