JP2007035335A - Vehicular lighting fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular lighting fixture which can obtain a heat dissipation effect without dirt and the like adhering to a heat sink with a simple structure. <P>SOLUTION: A vehicular lighting fixture 10 comprises a case 11 with the front open, at least one light source unit 12 having semiconductor light emitting elements which are arranged so as to emit light toward the front in the case, a front lens 13 which closes the open front of the case and is made of a transparent material, and a heat sink 14 placed in the case so as to attach to the light source unit. The vehicular lighting fixture 10 is equipped with an air cooling mechanism 20 having a rotary axis 21 which penetrates through the case from the inside to the outside, and windmill fans 22, 23 which are mounted on the both ends of the rotary axis. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicular lamp including a headlamp that uses a semiconductor light emitting element as a light source.

Conventionally, a vehicular lamp using a semiconductor light emitting element as a light source is configured as shown in FIG. 3, for example.
That is, in FIG. 3, a vehicular lamp 1 is configured as a headlight of an automobile, and includes a resin casing 2 having an open front surface, a light source unit 3 provided in the casing 2, and a casing. The front lens 4 is attached to the housing 2 so as to cover the front surface of the body 2.

The light source unit 3 includes at least one semiconductor light emitting element (not shown) such as an LED, and is supported inside the housing 2 by a unit support 3a so as to emit light forward. Yes.
Further, the light source unit 3 is attached to the unit support 3a via a heat sink 3b in order to dissipate heat generated by driving the semiconductor light emitting element.

  According to the vehicular lamp 1 having such a configuration, by supplying power to the light source unit 3 from the outside, the semiconductor light emitting element of the light source unit 3 is driven to emit light. Then, light emitted from the semiconductor light emitting element of the light source unit 3 is irradiated forward through the front lens 4.

In general, in such a vehicular lamp 1, heat is generated as the semiconductor light emitting element emits light.
By the way, it is known that semiconductor light-emitting elements generally have a negative characteristic with respect to temperature, that is, light emission efficiency decreases as the temperature increases.
Therefore, in the vehicle lamp 1, heat from the semiconductor light emitting element is radiated into the air in the housing 2 via the heat sink 3b.

Further, in Patent Document 1, a semiconductor light emitting element (LED) is supported in the vicinity of one end of a heat pipe, and the other end of the heat pipe is arranged outside the housing, and a heat sink is attached to generate each LED. A vehicular lamp is disclosed in which heat to be discharged is released from the heat sink outside the housing to the outside air via a heat pipe.
JP 2004-127782 A

By the way, in the vehicle lamp 1 described above, heat from the semiconductor light emitting element is dissipated into the air in the housing 2. And the air in the housing | casing 2 of this lamp | ramp 1 for vehicles is heated in this heat | fever, and natural convection is produced in the housing | casing 2, so that it circulates in the housing | casing 2 and the heat dissipation effect is improved more. It has become.
However, in the above-described vehicle lamp 1, heat dissipation in the housing 2 is limited to air circulation by natural convection in the housing 2. From this, the vehicular lamp 1 has a limit in the heat dissipation effect, and in some cases, the semiconductor light emitting element emits light with the heat dissipation effect lowered. As a result, the light efficiency of the semiconductor light emitting device 1 is further reduced, and the light emission color may change depending on the situation, and the vehicular lamp 1 is not suitable as a light source for a vehicular lamp in which the color of the light is regulated. It will be appropriate.

  On the other hand, it is also conceivable to incorporate a small fan in the housing 2 and forcibly circulate the air in the housing 2. However, even in this case, it is necessary for the vehicular lamp 1 to secure the lead-in of the power supply line for the fan and the space for accommodating the fan. Generate vibration, the vehicle lamp 1 is required to have a vibration-proof performance, and it is difficult to put it to practical use.

  In addition, it is possible to enhance the heat dissipation performance by extending the heat sink 3b to the outside of the housing 2, but the portion exposed to the outside of the heat sink 3b is exposed to the outside air, and pollutants of the outside air, etc. Therefore, it is considered that dirt adheres to the surface of the heat sink 3b. Therefore, in the case of long-term use, the heat dissipation performance of the heat sink 3b may be deteriorated due to dirt adhering to the surface, and in some cases, the minimum heat dissipation performance may not be guaranteed.

For this reason, for example, maintenance that periodically removes dirt adhering to the surface of the heat sink 3b by cleaning or the like becomes necessary.
Further, for example, when the optical axis of the vehicle lamp 1 is swung in conjunction with the steering operation by an AFS (Adaptive Front Lighting System), it is necessary to swing the heat sink 3b in accordance with the swing of the light source unit 3. Therefore, the mechanical fastening of the light source unit 3 to the housing 2 is hindered.

On the other hand, the vehicular lamp according to the patent document is configured to reduce the temperature inside the entire casing by conducting heat generated in each semiconductor light emitting element inside or outside the casing.
However, in this case as well, since the heat sink is disposed outside the housing, similarly, in the case of long-term use, dirt adheres to the surface of the heat sink and the heat dissipation performance is deteriorated.

  In view of the above, the present invention provides a vehicular lamp that can maintain the performance of a light source using a semiconductor light emitting device by obtaining an excellent heat dissipation effect with a simple configuration. It is aimed.

  According to the present invention, the above object is achieved by at least one light source unit having a housing that is open at the front, a semiconductor light emitting element that is arranged to emit light forward in the housing, and the housing A vehicular lamp including a front lens made of a translucent material that closes the opened front surface of the light source, and a heat sink disposed in the housing so as to contact the light source unit. This is achieved by a vehicular lamp characterized by including an air cooling mechanism that has a rotating shaft that passes through and is rotatably supported, and a windmill fan that is attached to both ends of the rotating shaft.

  The vehicular lamp according to the present invention preferably includes an outer wind guide duct for guiding running wind to the wind turbine fan outside the air cooling mechanism when the vehicle is running.

  The vehicular lamp according to the present invention preferably includes an inner wind guide duct for guiding an air flow from a wind turbine fan inside the air cooling mechanism to the heat sink.

  In the vehicular lamp according to the present invention, preferably, the inner air guide duct is made of a heat insulating material.

  In the vehicle lamp according to the present invention, preferably, a plurality of light source units are arranged in the housing, and a single heat sink is provided in contact with each light source unit, and the heat sink corresponds to each light source unit. The air cooling mechanism is provided.

  The vehicular lamp according to the present invention preferably includes a plurality of light source units arranged in the housing, and includes a plurality of heat sinks respectively in contact with the light source units, and each heat sink corresponds to the light source unit. The air cooling mechanism is provided.

According to the above configuration, by supplying power from the outside to the semiconductor light emitting elements of each light source unit, the individual semiconductor light emitting elements are driven to emit light.
And the light radiate | emitted from each light source unit is irradiated toward the front through the said front lens.
In this case, the heat generated in the semiconductor light emitting element of each light source unit is transmitted to the heat sink and further radiated from the heat sink to the air in the housing. The heated air is circulated in the housing by convection.

  At that time, the wind turbine fan outside the air cooling mechanism receives the traveling wind and rotates like a turbine as the automobile travels, so that the inner wind turbine fan connected to the outside wind turbine fan via the rotating shaft. Also rotates and functions as a compressor, thereby generating an air flow. As a result, the air flow generated by the inner windmill fan flows in the vicinity of the heat sink, thereby cooling the heat sink. Accordingly, since the heat sink is forcibly cooled by the air cooling mechanism, the heat dissipation efficiency by the heat sink is improved.

Thus, according to the present invention, since the temperature rise of the individual semiconductor light emitting elements in each light source unit is suppressed, the luminous efficiency of the individual semiconductor light emitting elements is not lowered, and high luminance can be maintained. become.
In addition, according to the present invention, since only the air in the housing is in contact with the heat sink, dirt is not attached to the heat sink with use, and highly reliable heat dissipation performance can be obtained over a long period of time. become.

  Since the heat from the heat sink is dissipated to the entire air in the housing, the front lens is slightly warmed through the air in the housing, so that the light from the semiconductor light emitting element has a so-called radiant heat effect. Even if it is not, a certain amount of snow melting effect in the front lens can be obtained.

  When the wind turbine fan outside the air cooling mechanism is provided with an outer wind guide duct for guiding the running wind when the vehicle is running, the running wind is efficiently passed through the outer wind guide duct when the vehicle is running. Since the outer windmill fan is guided to the outer windmill fan, the outer windmill fan can be efficiently rotated, and the air cooling effect by the inner windmill fan is improved.

  In the case where an inner air guide duct for guiding the air flow from the wind turbine fan inside the air cooling mechanism to the heat sink is provided, the air flow generated by the inner wind turbine fan passes through the inner air guide duct. Since it is guided to the heat sink, the air flow efficiently hits the heat sink, and the air cooling effect by the inner windmill fan is improved.

  When the inner air duct is made of a heat insulating material, the air flow passing through the inner air duct is not heated through the inner air duct, so that the heat sink can be efficiently cooled. .

  In the case where a plurality of light source units are arranged in the housing, and a single heat sink is provided in contact with each light source unit, and the heat sink includes the air cooling mechanism corresponding to each light source unit. Even if a plurality of light source units are provided, since one common heat sink in contact with each light source unit is provided with the air cooling mechanism corresponding to each light source unit, each light source unit has a corresponding air cooling function. The mechanism can efficiently dissipate heat.

  In the case where a plurality of light source units are arranged in the casing, and each of the heat sinks includes the air cooling mechanism corresponding to the light source unit. Even if a plurality of light source units are provided, the heat sinks that abut each of the light source units are each provided with the air cooling mechanism, so that each light source unit can be efficiently dissipated by the corresponding air cooling mechanism. Become.

  Thus, according to the present invention, in the vehicular lamp having at least one light source unit including the semiconductor light emitting element, the outer windmill fan rotates in response to the traveling wind of the automobile, and thus interlocks with this. An inner windmill fan arranged in the casing rotates to generate an air flow circulating in the casing. As a result, the heat sink is efficiently radiated by the air flow forcibly circulating in the housing, so that a decrease in the luminous efficiency of each semiconductor light emitting element of each light source unit due to a temperature rise can be suppressed, and the heat sink Since only the air in the housing is touched, dirt contained in the outside air does not adhere to the heat sink.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
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. As long as there is no description of the effect, it is not restricted to these aspects.

[Example 1]
FIG. 1A shows the configuration of the first embodiment of the vehicular lamp according to the present invention.
In FIG. 1 (A), a vehicular lamp 10 is an LED headlamp for an automobile, and includes a resin casing 11 having an open front surface and at least one (shown in the figure) provided in the casing 11. 1) the light source unit 12, a front lens 13 made of a translucent resin material attached to the housing 11 so as to cover the front surface of the housing 11, a heat sink 14 provided in the housing 11, and And an air cooling mechanism 20.

The light source unit 12 includes at least one semiconductor light emitting element (not shown) such as an LED (light emitting diode) or a laser diode, and is encased by a unit support 12a so as to emit light forward. It is supported inside the body 11.
Here, the light source unit 12 is supported on the inner side of the housing 11 by two unit support bodies 12a extending in the lateral direction above and below.

  The front lens 13 is made of a translucent resin material, and is attached to the housing 2 so as to airtightly cover the front surface of the housing 11.

The heat sink 14 is disposed in the housing 11 and is in contact with the light source unit 12 so that heat generated by the light source unit 12 is conducted and dissipated.
Here, in the illustrated case, the heat sink 14 is attached to the upper surface of the lower unit support 12 a and is in contact with the vicinity of the rear end of the light source unit 12. Thereby, the heat generated in each semiconductor light emitting element in the light source unit 12 can be efficiently transmitted to the heat sink 14.

The above configuration is the same as that of the conventional vehicular lamp 1 shown in FIG. 3, but the vehicular lamp 10 according to the embodiment of the present invention further includes the air cooling mechanism 20 described above.
Here, the air cooling mechanism 20 includes a rotating shaft 21 that penetrates the bottom of the casing 11, windmill fans 22 and 23 attached to both ends of the rotating shaft 21, and outer air guide ducts 24. ing.

The rotating shaft 21 is supported in an airtight and rotatable manner with respect to the bottom of the housing 11.
The outer wind turbine fan 22 is disposed in the outer air guide duct 24 outside the housing 11 and functions as a turbine in response to the traveling wind B introduced into the outer air guide duct 24. It is designed to be rotationally driven.

  The inner windmill fan 23 is disposed in the casing 11 and functions as a compressor by rotating in conjunction with the rotating shaft 21, and as shown by an arrow A in the casing 11, Is generated.

  The outer air guide duct 24 is disposed outside the housing 11 and is formed so as to guide the traveling wind B to the outer windmill fan 22 when the automobile is running.

The vehicular lamp 10 according to the embodiment of the present invention is configured as described above. By supplying power to the light source unit 12 from the outside, the individual semiconductor light emitting elements of the light source unit 12 are driven to emit light.
The light emitted from the light source unit 12 is irradiated forward through the front lens 13.
In this case, heat generated in the individual semiconductor light emitting elements of the light source unit 12 is transmitted to the heat sink 14 and further radiated from the heat sink 14 to the air in the housing 11.

Here, when the automobile is traveling, traveling wind relatively flows from the front of the automobile as the automobile travels, and this traveling wind B is introduced into the outer air guide duct 24 and the outer windmill fan. 22 to the vicinity.
As a result, the outer windmill fan 22 receives the traveling wind B and rotates as a turbine, and this rotation rotates the inner windmill fan 23 via the rotation shaft 21, and this inner windmill fan 23 is rotated. Functions as a compressor to generate an air flow A.
In this case, the traveling wind B is efficiently guided to the vicinity of the outer wind turbine fan 22 through the outer air guide duct 24.

Therefore, the air flow A generated by the rotation of the inner windmill fan 23 flows in the vicinity of the heat sink 14 and circulates in the housing 11, thereby cooling the heat sink 14.
In this way, the heat sink 14 is forcibly cooled by the air cooling mechanism 20, the heat dissipation effect by the heat sink 14 is improved, and the temperature rise of the semiconductor light emitting element of the light source unit 11 can be efficiently suppressed. It will be.

Accordingly, a decrease in light emission efficiency due to a temperature increase of each semiconductor light emitting element of the light source unit 12 is suppressed, and a relatively high light emission efficiency can be maintained, and the light emission color does not change.
Further, since the airflow A generated by the inner windmill fan 23 circulates only in the housing 11, the surface of the heat sink 14 is not contaminated, and the airflow A is generated over a long period of time. There is no need for maintenance, and highly reliable heat dissipation performance can be obtained.

FIG. 1B is a modified example of the above-described first embodiment, and a dynamo structure is added. In FIG. 1B, the vehicular lamp 10 has substantially the same configuration as the vehicular lamp 10 shown in FIG. 1A, and the same components are denoted by the same reference numerals and description thereof is omitted. . This has a mechanism for air-cooling the heat sink 14 using traveling wind when the vehicle travels. In this case, a rotating shaft 21 penetrating a part of the casing 11 is provided, and windmill fans 22 and 23 are provided at both ends thereof. A windmill fan 22 outside the housing 11 serves as a turbine and rotates by receiving traveling wind. At the same time, the windmill fan 23 inside the housing 11 also rotates coaxially, and power is transmitted as a compressor, so that the heat sink 14 can be cooled and circulated with clean air inside the housing 11 rather than dirty outside air. With regard to this structure, a gear is further provided in the coaxial part of the fan, and the tip of the gear is connected to the dynamo by gear drive to generate power. Furthermore, a storage battery (which may be shared with a normal vehicle battery or a dedicated battery) and an electric DC motor are incorporated.
The effect is that when the vehicle is not running, the stored electricity can be used to turn the fan, so a cooling effect can be expected even when the vehicle is idling.

[Example 2]
FIG. 2A shows the configuration of the second embodiment of the vehicular lamp according to the present invention.
2A, the vehicular lamp 30 has substantially the same configuration as the vehicular lamp 10 shown in FIG. 1A, and the same components are denoted by the same reference numerals and description thereof is omitted. . The vehicle lamp 30 is different from the vehicle lamp 10 shown in FIG. 1A only in that an inner air duct 31 is provided.

  The inner air duct 31 is made of a heat insulating material, and is arranged in the housing 11 so as to guide the air flow A generated by the rotation of the inner windmill fan 23 to the heat sink 14.

According to the vehicular lamp 30 having such a configuration, the air flow A generated by the rotation of the inner windmill fan 23 is operated in the same manner as the vehicular lamp 10 shown in FIG. The duct 31 is efficiently guided to the vicinity of the heat sink 14 and the cooling efficiency of the heat sink 14 is enhanced.
At that time, the air flow A guided to the vicinity of the heat sink 14 is not heated by the air in the housing 11 because the inner air duct 31 is made of a heat insulating material. Is further enhanced.
Accordingly, a decrease in light emission efficiency due to a temperature increase of each semiconductor light emitting element of the light source unit 12 can be further suppressed.

In the embodiment described above, the light source unit 12 includes a semiconductor light emitting element such as an LED, but the semiconductor light emitting element may be a light emitting element other than an LED, such as a semiconductor laser element.
In the embodiment described above, the single light source unit 12 is provided in the housing 11, but the present invention is not limited thereto, and a plurality of light source units 12 may be provided.
In this case, one common heat sink 14 may be provided for each light source unit 12, and one heat sink 14 may be provided for each light source unit 12. One light cooling mechanism 20 is provided for each light source unit 12.

  FIG. 2B is a modification of the above-described second embodiment, and a structure similar to a so-called stirrer is added. 2B, the vehicular lamp 30 has substantially the same configuration as the vehicular lamp 30 shown in FIG. 2A, and the same components are denoted by the same reference numerals and description thereof is omitted. . In this case, magnets are embedded in part of the windmill fans 22 and 23, and the windmill fan 22 on the outer side of the casing 11 and the windmill fan 23 on the inner side are coupled by a magnetic force. Keeps high compared to.

  The vehicular lamp 10 according to the present invention is configured as an automotive LED headlamp. However, the vehicular lamp 10 is not limited to this, and is applicable to other types of vehicular lamps including auxiliary headlamps such as fog lamps and driving lamps, backup lamps, and the like. The present invention can be applied.

  In this way, according to the present invention, an extremely excellent vehicular lamp can be provided that has a simple configuration and can obtain a heat dissipation effect without adhering dirt or the like to the heat sink. .

(A) is schematic sectional drawing which shows the structure of 1st embodiment of the vehicle lamp by this invention, (B) Schematic sectional drawing which shows the modified example structure of 1st embodiment of the vehicle lamp by this invention It is. (A) is a schematic sectional drawing which shows the structure of 2nd embodiment of the vehicle lamp by this invention, (B) is schematic sectional which shows the modification structure of 2nd embodiment of the vehicle lamp by this invention. FIG. It is a schematic sectional drawing which shows the structure of the conventional vehicle lamp.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,30 Lamp 11 Housing | casing 12 Light source unit 12a Unit support body 13 Front lens 14 Heat sink 20 Air-cooling mechanism 21 Rotating shaft 22 Outside windmill fan 23 Inside windmill fan 24 Outside wind guide duct 31 Inside wind guide duct

Claims (6)

A housing having a front opened, at least one light source unit having a semiconductor light emitting element arranged to irradiate light forward in the housing, and a translucent material that closes the opened front of the housing A vehicular lamp including a front lens comprising: a heat sink disposed in the housing so as to contact the light source unit;
An air cooling mechanism having a rotating shaft that penetrates the casing from the inside to the outside and is rotatably supported, and a windmill fan attached to both ends of the rotating shaft, is provided for a vehicle. Light fixture.   2. The vehicular lamp according to claim 1, further comprising an outer wind guide duct for guiding a running wind to the wind turbine fan outside the air cooling mechanism when the vehicle is running. 3.   3. The vehicular lamp according to claim 1, further comprising an inner wind guide duct for guiding an air flow from a wind turbine fan inside the air cooling mechanism to the heat sink.   The vehicular lamp according to claim 3, wherein the inner air duct is made of a heat insulating material.   A plurality of light source units are arranged in the housing, and a single heat sink is provided in contact with each light source unit, and the heat sink includes the air cooling mechanism corresponding to each light source unit. The vehicular lamp according to any one of claims 1 to 4, characterized in that:   A plurality of light source units are arranged in the housing, and a plurality of heat sinks are provided in contact with the light source units, respectively, and each heat sink is provided with the air cooling mechanism corresponding to each light source unit. The vehicle lamp according to any one of claims 1 to 4.

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