JP2008084700A - Led lighting fixture for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED lighting fixture suppressing temperature rise in an LED light source by enhancing heat discharging property for self generated heat in the LED light source and therefore reducing deterioration in light emitting efficiency of the LED light source and securing a prescribed amount of radiation of light in the LED lighting fixture for the vehicle with the LED as the light source. <P>SOLUTION: In the lighting fixture unit 5 supported in a lamp chamber 4 formed by a front surface lens 2 and a housing 3, all the connecting members including a mounting plate 7 on which a mounting board for the LED light source 6 is mounted, a heat sink 12 to which the mounting plate 7 is fixed to, a heat sink supporting plate 13 supporting the heat sink 12, a bracket 16 which is aimed and fixed to the housing 3, and a fixing screw 14 connecting and fixing the heat sink supporting plate 13 and the bracket 16 are formed of metal material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle LED lamp using an LED as a light source.

  The LED has a characteristic that the light emission efficiency decreases as the temperature rises. Possible causes of LED temperature rise include self-heating during lighting and exposure to a high temperature environment.

  On the other hand, LEDs generally have advantages such as small size, low power consumption, and long life compared to various lamps. Conventionally, LEDs have been used to make high-mount stop lamps, stop-and-tail lamps, turn signals, etc. In recent years, a vehicle headlamp using an LED as a light source has been proposed.

  In general, a vehicular lamp has a lamp chamber formed by a front lens and a housing, and an LED serving as a light source is supported in the lamp chamber. When the LED is turned on, the temperature of the LED itself rises due to the self-heating of the LED, and as a result, the light emission efficiency of the LED decreases and the amount of irradiation light of the lamp decreases, and in the extreme case due to the deterioration of the light distribution performance There is also a possibility that the light distribution standard required for the lamp will not be satisfied.

  Therefore, proposals have been made for vehicle headlamps that prevent the occurrence of the above problems. As shown in FIG. 7, the vehicle head includes a transparent cover 51, a lamp body 52, a support bracket 56 in which the vertical panel portion 53, the unit support portion 54 and the heat sink portion 55 are integrated, and a socket cover 57. A lamp chamber 58 of the lamp 50 is formed, and the vertical panel portion 53 and the unit support portion 54 of the support bracket 56 are located in the lamp chamber 58 of the headlamp 50, and the heat sink portion 55 is a lamp chamber 58 of the headlamp 50. It extends outside.

  A semiconductor light emitting element 59, a reflector 60, and a light control member 61 are fixed to the unit support portion 54 of the support bracket 56 located in the lamp chamber 58 of the headlamp 50. The light control member 61 includes a projection lens 62. I support it.

In the vehicle headlamp 50 having the above-described configuration using the semiconductor light emitting element 59 as a light source, self-heating when the semiconductor light emitting element 59 is turned on is a unit support portion 54 of a support bracket 56 formed of a material that is a good conductor of heat. Then, the heat is transferred from the heat sink portion 55 to the heat sink portion 55, and is dissipated outside the lamp chamber 58 by the heat sink portion 55. Thereby, the temperature rise of the semiconductor light emitting element 59 itself when the semiconductor light emitting element 59 is turned on is suppressed (see, for example, Patent Document 1).
JP-A-2005-141917

  In the conventional vehicle headlamp 50, most of the heat generated in the semiconductor light emitting device 59 is conducted from the unit support portion 54 of the support bracket 56 on which the semiconductor light emitting device 59 is mounted to the heat sink portion 55 to be heat sink. The light is dissipated outside the lamp chamber 58 at the section 55.

  By the way, the heat sink portion 55 has a higher heat dissipation efficiency and a better heat dissipation effect as the heat dissipation area of the entire surface of the heat sink portion 55 in contact with the outside air (air) is larger. In other words, the size of the heat sink portion 55 is related to the heat dissipation efficiency. However, when the heat sink portion 55 is increased, the entire vehicle headlamp 50 is increased and the weight is also increased. For this reason, it is conceivable that the degree of freedom in designing the dimensions of the heat sink portion 50 cannot be ensured due to the mounting space and weight restrictions of the vehicle headlamp 50, and sufficient heat dissipation efficiency cannot be obtained.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to increase the heat dissipation of self-heating of the LED while maintaining the small size and light weight in the vehicle LED lamp using the LED as a light source. Accordingly, an object of the present invention is to provide a vehicular LED lamp that suppresses the temperature rise of the LED, thereby suppressing a decrease in the light emission efficiency of the LED and ensuring a predetermined amount of irradiation light.

  In order to solve the above problems, the invention described in claim 1 of the present invention is generated by at least one LED light source, an optical system for controlling an optical path of light emitted from the LED light source, and the LED light source. A heat sink for dissipating the heat is integrated, and the integrated LED light source, the optical system, and the heat sink are connected and fixed to a bracket made of a metal material through a connecting member made of a metal material. The lamp unit is supported through the bracket in at least a lamp chamber formed by a front lens and a housing.

  According to a second aspect of the present invention, in the first aspect, the optical system includes at least a reflector, and the reflector is made of a metal material.

  The invention described in claim 3 of the present invention is characterized in that, in any one of claims 1 and 2, the lamp unit is supported in a tiltable manner in the lamp chamber via the bracket. It is what.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the LED light source is one of an LED chip and an LED device including the LED chip. It is what.

  The vehicle LED lamp according to the present invention integrates at least one LED light source, an optical system that controls an optical path of light emitted from the LED light source, and a heat sink that dissipates heat generated by the LED light source, and The lamp unit was configured by connecting and fixing the converted LED light source, optical system, and heat sink to a bracket made of a metal material via a connection member made of a metal material.

  Therefore, the self-heating generated when the LED light source is turned on is dissipated by both the heat sink and the bracket, the heat dissipation of the lamp unit having the LED light source is improved, and the temperature rise of the LED light source is suppressed, so the luminous efficiency of the LED light source It is possible to secure a predetermined amount of irradiation light.

  Also, since the bracket can share a part of the heat dissipation amount that the heat sink part conventionally has, even if the heat sink part is made smaller than before and the heat dissipation from the heat sink part is reduced, the lamp unit as a whole It is possible to ensure sufficient heat dissipation.

  Therefore, it is possible to reduce the size of the vehicle LED lamp by reducing the size of the heat sink, and particularly to reduce the depth in the vehicle front-rear direction when mounted on the vehicle, and to reduce the weight of the vehicle LED lamp. Can do.

  Therefore, it is possible to reduce the size of the heat sink while ensuring the heat dissipation efficiency of the entire lamp, and to ensure the degree of design freedom while maintaining the heat dissipation performance even if there is a restriction on the installation space of the lamp Is possible.

  Further, by forming the reflector constituting the optical system with a metal material, a further heat dissipation effect can be obtained.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6 (the same parts are denoted by the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is a cross-sectional view of a vehicle LED lamp according to the present invention. In the vehicular LED lamp 1, a lamp chamber 4 is formed by a front lens 2 and a housing 3, and a lamp unit 5 is supported in the lamp chamber 4.

  The lamp unit 5 includes an optical system and a heat dissipation system. The optical system is connected to the LED light source 6, the mount plate 7 on which the mounting substrate of the LED light source 6 is placed, the reflector 8 connected to the mount plate 7, and the reflector 8. The lens holder 9, the shield 10 extending upward from the inner bottom surface of the lens holder 9, and the projection lens 11 supported by the lens holder 9 form a projector lamp.

  On the other hand, the heat dissipation system includes a mount plate 7 on which a mounting substrate of the LED light source 6 is placed, a heat sink 12 to which the mount plate 7 is fixed, a heat sink support plate 13 that is fixed to the heat sink 12 and supports the heat sink 12, and a heat sink support plate 13. And a bracket 16 that is supported by the housing 3 via an aiming screw 15 so as to be tiltable.

  In this case, a mechanism as shown in FIGS. 2 and 3 is used for connecting and fixing the heat sink support plate 13 and the bracket 16 with a fixing screw. 2 is a cross-sectional view of part A in FIG. 1, and FIG. 3 is a cross-sectional view of part B in FIG.

  As shown in FIG. 2, the heat sink support plate 13 and the bracket 16 are both made of a metal material such as Al or Cu. The heat sink support plate 13 is provided with a columnar boss 17 extending toward the bracket 16, and a tap hole 18 extending from the bracket 16 side is formed at the center thereof.

  On the other hand, the bracket 16 is provided with an arcuate recess 19 that is recessed in the opposite direction with respect to the heat sink support plate 13, and a screw insertion hole 20 is formed at the center thereof.

  The tip 21 of the boss 17 of the heat sink support plate 13 is brought into contact with the concave portion 19 of the bracket 16, and the fixing screw 14 made of a metal material is inserted through the screw insertion hole 20 of the bracket 16, so that the boss 17 of the heat sink support plate 13. The tapped hole 18 is screwed.

  Further, as shown in FIG. 3, the heat sink support plate 13 is provided with a boss 17 extending in the opposite direction with respect to the bracket 16, and a tap hole 18 penetrating the center is formed at the center.

  On the other hand, a screw insertion hole 20 is formed in the bracket 16.

  A cylindrical spacer 22 is disposed between the bracket 16 and the heat sink support plate 13, and the fixing screw 14 is inserted through the screw insertion hole 20 and the spacer 22 of the bracket 16, thereby tapping the boss 17 of the heat sink support plate 13. 18 is screwed.

  Further, the aiming fixing of the bracket 16 to the housing 3 by the aiming screw 15 employs a mechanism as shown in FIG. FIG. 4 is a cross-sectional view of part C of FIG.

  As shown in FIG. 4, an aiming nut 23 having a tap hole 18 is attached to the heat sink support plate 13, and a screw insertion hole 20 is formed in the bracket 16. The aiming screw 15 is inserted into the screw insertion hole 20 of the bracket 16 and screwed into the tap hole 18 attached to the heat sink support plate 13.

  Next, the state of light in the optical system and the state of heat in the heat dissipation system will be described.

  First, in the optical system, as shown in FIG. 5, when the LED light source 6 is turned on and emits light, the light from the LED light source 6 toward the reflector 8 is reflected by the reflector 8 toward the projection lens 11 in the front, Part of the light path is blocked by the shield 10. On the other hand, of the light reflected by the reflector 8, the light that is not blocked by the shield 10 is guided through the lens holder 9 to the projection lens 11, and is controlled by the projection lens 11 to a desired light distribution to be in front. The light is irradiated in front of the vehicle LED lamp 1 through the lens 2.

  At this time, when the aiming screw 15 for aiming and fixing the bracket 16 and the housing 3 in FIG. 1 is rotated, the lamp unit 5 including the bracket 16 is tilted via the bracket 16 and the optical axis X of the optical system (projector lamp) is tilted. The direction can be adjusted.

  Next, in the heat dissipation system, when the LED light source 6 is turned on as shown in FIG. 6, the LED light source 6 emits light and also generates heat. The heat (self-heating) generated by the LED light source 6 moves to the substrate on which the LED light source 6 is mounted, and is conducted through the LED light source 6 mounting substrate to move to the mount plate 7 on which the substrate is placed. The heat transferred to the mount plate 7 is conducted through the mount plate 7 and moves to the heat sink 12 to which the mount plate 7 is fixed.

  A part of the heat transferred to the heat sink 12 is conducted in the heat sink 12 to reach the surface of the heat sink 12, and the heat reaching the surface of the heat sink 12 is transferred to the air in the vicinity of the surface and transferred to the air. Is diffused out of the heat sink 12 as a medium.

  A part of the heat transferred to the heat sink 12 is transferred to the heat sink support plate 13 made of a metal material that is conducted through the heat sink 12 and fixed to the heat sink 12 to support the heat sink 12.

  Part of the heat transferred to the heat sink support plate 13 is conducted through the heat sink support plate 13 to reach the surface of the heat sink support plate 13, and the heat reaching the surface of the heat sink support plate 13 is transferred to the air near the surface. It is transferred by heat transfer and is dissipated out of the heat sink support plate 13 using air as a medium.

  Further, part of the heat transferred to the heat sink support plate 13 moves to a fixing screw 14 made of a metal material that connects and fixes the heat sink support plate 13 and the bracket 16 made of a metal material. The heat transferred to the fixing screw 14 is conducted through the fixing screw 14 and moves to the bracket 16.

  At the same time, a portion where the tip 21 of the boss 17 of the heat sink support plate 13 is in contact with the recess 19 of the bracket 16 and a cylindrical spacer 22 disposed between the bracket 16 and the heat sink support plate 13 are also used. Heat is transferred from the heat sink support plate 13 to the bracket 16.

  The heat transferred to the bracket 16 is conducted through the bracket 16 to reach the surface of the bracket 16, and the heat reaching the surface of the bracket 16 is transferred to the air in the vicinity of the surface and moved. It is dissipated out of the bracket 16 using air as a medium.

  The reflector 8 is formed of a metal material such as Al or Cu, like the heat sink support plate 13 and the bracket 16, so that a part of the heat generated in the LED light source 6 and transferred to the mount plate 7 is moved to the reflector 8. It is also possible to transfer heat to the air in the vicinity of the surface of the reflector 8 and dissipate it out of the reflector 8 using air as a medium.

  As described above, the vehicle LED lamp according to the present invention includes the mount plate 7 on which the mounting substrate of the LED light source 6 is placed, the heat sink 12 to which the mount plate 7 is fixed, the heat sink support plate 13 that supports the heat sink 12, All the connecting members such as the bracket 16 fixed to the housing 3 and the fixing screw 14 for connecting and fixing the heat sink support plate 13 and the bracket 16 are formed of a metal material.

  Therefore, the heat generated from the LED light source 6 when the LED light source 6 is turned on is sequentially conducted to the heat sink 12, the reflector 8, the heat sink support plate 13 and the housing 3 through a heat conduction path having a small thermal resistance, and from each part to the outside. Dissipated.

  As a result, the heat dissipation of the lamp unit 5 having the LED light source 6 is improved, and a decrease in the light emission efficiency of the LED light source 6 is reduced by suppressing the temperature rise of the LED light source 6, thereby ensuring a predetermined amount of irradiation light. It becomes possible.

  In addition, since a part of the heat radiation amount conventionally carried by the heat sink 12 can be shared by the heat sink support plate 13, the bracket 16 and the reflector 8, the heat sink 12 can be made smaller than the conventional one to reduce the heat radiation amount from the heat sink 12. Even if it becomes, it becomes possible to ensure sufficient heat dissipation as the lamp unit 5 whole.

  Therefore, the downsizing of the heat sink 12 enables the downsizing of the vehicular LED lamp and the weight of the vehicular LED lamp can be reduced.

  Therefore, it is possible to reduce the size and weight while ensuring the heat radiation efficiency of the entire lamp, and it is possible to ensure a degree of design freedom even if restrictions are imposed on the installation space and weight of the lamp.

  The LED light source 21 may be an LED bare chip (LED chip) or an LED device in which the LED chip is mounted on a package.

It is sectional drawing of the LED lamp for vehicles of this invention. It is A section sectional drawing of FIG. Similarly, it is B section sectional drawing of FIG. Similarly, it is C section sectional drawing of FIG. Similarly, it is the fragmentary sectional view of FIG. Similarly, it is another partial sectional view of FIG. It is sectional drawing of the conventional vehicle lamp.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 LED lamp for vehicles 2 Front lens 3 Housing 4 Light chamber 5 Lamp unit 6 LED light source 7 Mount plate 8 Reflector 9 Lens holder 10 Shielding body 11 Projection lens 12 Heat sink 13 Heat sink support plate 14 Fixing screw 15 Aiming screw 16 Bracket 17 Boss 18 Tap hole 19 Recess 20 Screw insertion hole 21 Tip 22 Spacer 23 Aiming nut

Claims (4)

  At least one LED light source, an optical system that controls an optical path of light emitted from the LED light source, and a heat sink that dissipates heat generated by the LED light source are integrated, and the integrated LED light source and the An optical system and the heat sink are connected and fixed to a bracket made of a metal material via a connecting member made of a metal material to constitute a lamp unit, and the lamp unit is formed in at least a lamp chamber formed by a front lens and a housing. A vehicle LED lamp characterized by being supported via a bracket.   The vehicular LED lamp according to claim 1, wherein the optical system includes at least a reflector, and the reflector is made of a metal material.   3. The vehicular LED lamp according to claim 1, wherein the lamp unit is supported in a tiltable manner in the lamp chamber via the bracket. 4.   The vehicle LED lamp according to any one of claims 1 to 3, wherein the LED light source is one of an LED chip and an LED device including the LED chip.

Images