JP2009272146A - Vehicular room light - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular room light having simple structure and low cost, efficiently and easily dissipating heat generated from a high power LED light-emitting element, having a structure in which heat is not accumulated in the high power LED light-emitting element, and having interchangeability with an existing vehicular room light. <P>SOLUTION: The vehicular room light 10 is composed of the high power LED light-emitting element 3 mounted on a substrate 2, and a heat dissipating plate 4 having graphite as a main component, in which an opening part 5 to expose the LED light-emitting element 3 is bored. The LED light-emitting element and the heat dissipating plate are disposed on the substrate to surround the peripheral fringe part of the LED light-emitting element 3 carried on the substrate 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle room light, and more particularly to a vehicle room light using a high-power LED light emitting element.

  Conventionally, a semiconductor light emitting device (LED) has been generally used as a light source for illumination. In particular, in recent years, a high-power LED light emitting device capable of outputting an output of 1 watt or more has been put into practical use. Progressing.

  However, semiconductor light emitting devices (LEDs) are much brighter than incandescent light bulbs as conventional light sources, and have been considered to have a wide range of application fields as various illumination light sources.

  However, since the semiconductor light emitting device (LED) emits a lot of thermal energy when emitting light, how to dissipate the generated heat has become a big problem when using the LED. If left unattended, the semiconductor light emitting device (LED) is destroyed by the heat, and conventionally, there is no appropriate heat treatment means. Therefore, the semiconductor light emitting device (LED) is a low-power semiconductor light emitting device. Devices (LEDs), for example, those with a power of 0.1 W or less can be used, or even high-power LED light-emitting devices are actually used in situations where only a power of 0.1 W or less can be output. It was only.

  In particular, for vehicle room lights, the position of the vehicle room lights is specified in advance, and for vehicle room lights, heat is dissipated from regulations on the interior structure and materials used of the vehicle. Since it is practically impossible to construct a system, only low-power semiconductor light emitting devices (LEDs) that generate as little heat as possible are currently used.

  In addition, as a general movement in the vehicle industry, parts such as vehicle room lights are low in production cost, and even if repairs are made, it is not possible to recover sufficient repair costs for the labor involved. Therefore, it is common sense to use the semiconductor light emitting device (LED) for a long time in a low output state without increasing the illuminance of the semiconductor light emitting device (LED) because it is necessary to reduce the failure and extend the lifetime as much as possible. .

Accordingly, the interior of the vehicle by the vehicle room light is dark, and it is extremely inconvenient for reading characters and checking a map.
The same background exists in the vehicular room light using a conventional incandescent bulb, and the interior of the vehicle illuminated by the vehicular room light is kept in a low heat generation temperature state. The fact that the color of was specified as a reddish color.

  In recent years, high-power LED light-emitting elements with an output exceeding 1 W are being put into practical use, and the brightness of the high-power LED light-emitting elements is much brighter than the illuminance of the incandescent light bulb. It is clear that the brightness inside the vehicle can be remarkably improved if it is used as a room light, but as mentioned above, how efficiently the problem of heat dissipation and dissipation of heat generated from the high-power LED light-emitting element can be solved. However, it was a problem to be solved by a low-cost method with few failures.

  On the other hand, a structure of a vehicle room light that replaces the incandescent light bulb of a vehicle room light using a conventional incandescent light bulb with a semiconductor light emitting element (LED) is disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-191037 (Patent Document 1), Although disclosed in Utility Model Registration No. 3133366 (Patent Document 2), Utility Model Registration No. 312847 (Patent Document 3), etc., in the known example, how to use a conventional incandescent light bulb? There is a technical proposal on the structural aspect of obtaining a vehicle room light that uses a semiconductor light emitting element (LED) as a light source from the used vehicle room light, but the semiconductor light emitting element (LED) is generated. There is no disclosure regarding the technology for controlling heat.

  That is, the known example uses an existing vehicle room light that uses an incandescent light bulb, and uses a pair of power supply portions that can be attached to and detached from the mounting base of the incandescent light bulb as it is. A semiconductor light emitting device (LED) is attached. Furthermore, in order to secure the brightness of the semiconductor light emitting device (LED), a plurality of semiconductor light emitting devices (LEDs) having a small output are collectively used as a light source. is there.

  Therefore, in the vehicle room light, there is a problem that the structure of the arrangement portion of the semiconductor light emitting element (LED) that is the light source becomes large, the usage is limited, and at the same time, the cost increases.

JP 2007-191037 A Utility Model Registration No. 3133366 Utility Model Registration No. 3129847

  The present invention has been made in view of the above-described conventional problems. The object of the present invention is to reduce the heat generated from the high-power LED light-emitting element efficiently with a simple configuration and without cost. Provided is a vehicle room light that is easily dissipated and has a structure in which the generated heat is not accumulated in the high-power LED light-emitting element, and is compatible with existing vehicle room lights. Is.

In order to achieve the above-described object, the present invention employs a technical configuration as described below.
That is, the first aspect of the present invention comprises a high-power LED light-emitting element mounted on a substrate and a heat dissipation plate mainly composed of graphite with an opening that exposes the LED light-emitting element. A vehicle room light characterized in that a board is joined and disposed on the substrate so as to surround a peripheral portion of the LED light emitting element mounted on the substrate, and the second aspect of the present invention. In the vehicle room light having the above-described configuration, the feeding portion of the high-power LED light-emitting element has a tubular or spherical transparent body portion having the same structure and the same size as the incandescent bulb of the existing vehicle room light. A vehicle room light characterized in that it has a base part corresponding to positive and negative electrodes that can be inserted into a mounting base for an existing incandescent light bulb, and a current limiting resistor is provided between the base parts. is there.

  According to the present invention, the heat generated from the high-power LED light-emitting element can be dissipated efficiently and easily with a simple configuration, and the increase in temperature of the high-power LED light-emitting element itself is suppressed. As described above, it is possible to use a high-power LED light-emitting element having a high output of preferably 2 W or more even in an environment where the light-emitting ability is limited, and illumination with high luminance and high illuminance can be easily obtained.

  Furthermore, according to the present invention, the vehicle room light is compatible with an existing vehicle room light that uses an incandescent bulb, so that the vehicle room light that has been attached to a conventional vehicle can be easily output at high power. It can be changed to a vehicle room light using LED light emitting elements.

  In the present invention, since a plate-like body made of flexible graphite is used for the heat radiating plate, the effect of being easily attached to a curved surface, a non-planar wall surface such as a spherical surface, a floor surface, a ceiling surface portion, etc. There is.

Next, embodiments of the present invention will be described with reference to the drawings.
That is, the configuration of one specific example of the vehicle room light 10 related to the first aspect of the present invention is shown in FIG. 1, in which a high-power LED light-emitting element mounted on a substrate 2 is shown. 3 and a heat radiating plate 4 having graphite as a main component in which an opening 5 exposing the LED light emitting device 3 is perforated, and the peripheral edge of the LED light emitting device 3 mounted on the substrate 2 A vehicle room light 10 characterized by being arranged on the board 2 so as to surround the part is shown.

The substrate 2 is preferably mounted with wiring means 8 including an electrode portion 6 and an appropriate wiring portion 7 for driving the high-power LED light emitting element 3.
Further, in the present invention, it is a preferable specific example that a connection wiring portion 9 of the power feeding portion 11 described later is connected to the electrode portion of the substrate 2.

  The high-power LED light-emitting element 3 used in the present invention is not particularly limited, but for example, a semiconductor light-emitting element (LED) having an output of 0.5 watts (W) or more is desirable. Preferably, a semiconductor light emitting element (LED) having an output of 1 watt (W) or more, more preferably 2 watts (W) or more can be used.

  The high-power LED light-emitting element 3 according to the present invention includes, for example, an element substrate 12 having a plane having a vertical and horizontal dimension of 3 mm to 7 mm and a thickness of about 0.8 to 1.5 mm. A high-power LED light-emitting element having a rectangular shape can be used. Specifically, a surface-mount type light-emitting diode SMD type manufactured by Nichia Corporation and an NJSW series or NFSW series can be used.

  As shown in FIG. 3 (A), the high-power LED light-emitting element 3 is provided with a light-emitting portion 13 made of LED on one front side of an element substrate portion 12 made of ceramic, for example. As shown in FIG. 3B, a pair of electrode portions 14 and 14 'made of a relatively wide conductive metal, for example, gold, are arranged in parallel.

The widths of the electrode portions 14 and 14 'in the present invention are preferably 10 to 40% of the width of the element substrate 12, for example.
In the present invention, the high-power LED light-emitting element 3 is arranged and mounted at an arbitrary position on an appropriate printed board 2 as shown in FIG. 2 is provided with a wiring part 7 for connecting the electrode part 6 and the electrode part 14 of the high-power LED light emitting element 2 as described above.

  Between the front and back surfaces of the printed circuit board 2, for example, a through hole is formed by a known means, and an appropriate conductive part for connecting the electrode part 14 of the high-power LED light emitting element 3 and the wiring part 7. 32 is provided.

  On the other hand, the heat radiating plate 4 used in the present invention is constituted by a flat plate-like body in which an opening 5 exposing the LED light emitting element 3 is perforated, as shown in FIG. The material of the heat radiating plate 4 needs to be a sheet-like material containing graphite as a main component.

That is, in the present invention, it is necessary to efficiently diffuse a high amount of heat energy generated from the high-power LED light-emitting element 3 to protect the high-power LED light-emitting element 3 from destruction by heat.
Therefore, as a result of intensive studies, the inventor of the present invention has a material made from natural graphite as a raw material, which is excellent in thermal conductivity, and more particularly heat in the plane direction than the thermal conductivity in the thickness direction of the sheet. Since it has a characteristic of high conductivity, heat generated from the light emitting LED as a heat source can be efficiently diffused over the entire surface of the heat radiating plate 4, and the heat generated from the light emitting LED can be effectively controlled. It is a wisdom that it is possible to do.

Since the heat sink 4 according to the present invention has flexible characteristics, even if it is a vehicle room light, a room light arranged on a three-dimensional surface or wall having a special shape, a corner portion, or the like. But it can be easily applied.
In this case, it is preferable to use a flexible material for the substrate 2 as well.

Further, the heat radiating plate 4 may be one using glass graphite mixed with the graphite. In this case, it is possible to give the heat radiating plate 4 more flexibility and strength. Become.
As a sheet material mainly composed of graphite required for the heat radiating plate in the present invention, for example, a high thermal conductive graphite sheet manufactured by Otsuka Electric Co., Ltd. can be used.

The heat sink 4 in the present invention is provided with an opening 5 having substantially the same shape as that of the high-power LED light-emitting element 3 and a size slightly larger than that of the high-power LED light-emitting element 3. ing.
In the present invention, the high-power LED light-emitting element 3 is desirably provided at a substantially central portion of the substrate 2, and therefore the opening 5 of the heat radiating plate 4 is also disposed at a substantially central portion of the heat radiating plate 4. Thus, the heat generated from the high-power LED light-emitting element 3 can diffuse and dissipate heat in the heat radiating plate 4 approximately evenly.

  In the specific example of the present invention, FIG. 1 shows a structure in which one high-power LED light emitting element 3 is arranged on the substrate and the heat sink 4 has one opening 5. In the present invention, the number of the high-power LED light-emitting elements 3 used is not limited to one, but a plurality of the high-power LED light-emitting elements 3 are provided in order to obtain necessary illuminance and brightness. It is also possible to use them simultaneously.

2 (A) and 2 (B) show an example using two high-power LED light emitting elements 3 and an example using three as other specific examples of the present invention.
That is, a plurality of the high-power LED light-emitting elements 3, 3 ′, 3 ″ and the like are arranged and mounted on the substrate 2 at a predetermined interval. A number of openings 5, 5 ', 5 "corresponding to the number of elements 3 are provided.

In the present invention, the size of the heat radiating plate is not particularly limited, but when heat is diffused and radiated, the area of the heat radiating plate is proportional to the amount of heat radiated. It is desirable to design the surface area as large as possible.
Similarly, it is desirable that the size and shape of the substrate 2 to be joined to the heat radiating plate 4 also match those of the heat radiating plate 4.

Therefore, the size of the substrate 2 and the heat radiating plate 4 is designed so as to realize the maximum surface area in consideration of the shape and capacity of the space in which the vehicle room light is accommodated.
The heat radiating plate 4 and the substrate 2 are bonded and fixed to each other using an appropriate adhesive.

  On the other hand, in the vehicle room light 10 according to the present invention, as described above, the power supply portion 11 that can be joined to an appropriate power supply portion for driving the high-power LED light emitting element 3 to emit light is provided. The part 11 is connected to the electrode part 14 of the high-power LED light emitting element 3 through an appropriate wiring part 9.

  And since the said electric power feeding part 11 in this invention needs to have a function which can replace the incandescent light bulb currently used for the existing vehicle room light, the mounting | wearing for the incandescent light bulb of the existing vehicle room light is carried out. It is desirable to have a shape and dimensions that can be inserted into the base.

  That is, incandescent light bulbs of the existing vehicle room lights are generally classified into, for example, a tube bulb type (tubular light emitter) as shown in FIG. 4A and a pin bulb type (as shown in FIG. 4B). In a bulb-type incandescent bulb, a mounting base corresponding to a pair of positive and negative power sources for mounting the base portions provided at both ends of the columnar light emitting portion is used in the vehicle room. In the tube-type incandescent lamp, the mounting caps 16 and 16 corresponding to the positive and negative power sources for mounting the caps 15 and 15 ′ provided at both ends of the cylindrical portion 40 are provided. Since 'is provided in the vehicle room light, it is desirable that the power feeding section 11 in the present invention also has a shape and size that can be mounted on the existing mounting caps 16 and 16'.

  Similarly, when the incandescent light bulb used for the existing vehicle room light is a pin bulb type (spherical light emitter), it corresponds to the cylindrical cap portion 15 ″ of the pin bulb type bulb. Since the cylindrical mounting base 16 ″ is provided in advance, it is desirable that the power supply portion 11 in the present invention also has a cylindrical base portion 15 ″ as shown in FIG.

As described above, the power feeding portion 11 in the present invention has the cylindrical base portion 15 having the same structure and the same dimensions as the incandescent bulb of the existing vehicle room light. The base part 15 is configured to be able to be inserted into an existing mounting base 16, 16 'or 16 ".
And in the said electric power feeding part 11 in this invention, the current limiting resistor containing the coil which controls the drive of the said high output LED light emitting element 3 in the said base part 15, 15 'or the said base 15 "inside 17 is provided.

The resistance value of the current limiting resistor 17 is appropriately set depending on the capability, the number, and the like of the high-power LED light emitting element 3 to be used.
The current limiting resistor 17 in the present invention is preferably a cement resistor.
That is, in this invention, the said electric power feeding part 11 is used instead of the incandescent lamp currently used for the existing vehicle room light.

  And in this invention, after the said electric power feeding part 11 of the said high output LED light emitting element arrange | positions the said current limiting resistor 17 between the said pair of mounting bases 15 and 15 ', or in the said cylindrical mounting base 15 ", It is also a desirable example that the current limiting resistor 17 is made of an insulating resin such as PPS resin so that at least a part or all of the current limiting resistor 17 is covered in a cylindrical shape.

In the present invention, the current limiting resistor 17 of the power supply unit 11 is covered with the PPS resin because the PPS resin is excellent in heat resistance and insulation, and has good moldability and low cost. That is why.
On the other hand, in the power supply unit 11 of the high-power LED light emitting element, an opening is formed between a pair of the mounting caps 15 and 15 'or a part of the PPS resin 24 disposed in the cylindrical mounting cap 15''. It is also a desirable specific example that the portion 30 is provided and at least a part of the current limiting resistor 17 is exposed from the PPS resin.

That is, instead of covering the entire surface of the power supply unit 11 with the insulating resin 24, as shown in FIG. 4E, an opening 30 is provided in the covering layer of the insulating resin 24, and the current Exposing part of the limiting resistor 17 is also a preferable specific example.
By adopting the above configuration, since the current limiting resistor 17 is connected to air, an air cooling effect is obtained, which is convenient for temperature control.

Next, the electrical connection relationship between the high-power LED light-emitting element 3 and the power feeding unit 11 in the present invention will be described with reference to FIG.
That is, as shown in FIG. 5, in the power feeding unit 11, one end of the current limiting resistor 17 is connected to one cap 15 and the other end of the current limiting resistor 17 is maintained in a float state. In addition, the wiring portion 9 connected to one electrode portion 14 of the high-power LED light emitting element 3 is connected to the other end portion of the current limiting resistor 17 maintained in the float state, and the high-power LED A wiring part 9 ′ connected to the other electrode part 14 ′ of the light emitting element 3 is connected to the other base part 15 ′.

The tip of the float portion of the current limiting resistor 17 is held inside the insulating resin 24.
The above-described wiring structure is the same also in the power feeding unit 11 corresponding to the pin ball type.
In FIG. 5, S is a switch.
As still another aspect of the present invention, as shown in FIGS. 1 and 6, a buffer material 20 is provided on the peripheral portion of the surface of the substrate 2 opposite to the surface on which the heat sink 4 is mounted. The buffer material 20 is an appropriate material and is made of a material having elasticity and resilience, and the thickness is not particularly limited. It is desirable that a sufficient groove or recess 21 is provided to accommodate the portion 11.

In the present invention, it is also a desirable specific example that an appropriate adhesive 23 is applied to the surface 22 of the buffer material 20.
By adopting such a configuration, the vehicle room light according to the present invention can be used for the existing vehicle by using an appropriate adhesive stuck to the cushioning material 20 in the existing vehicle room light. At the same time as joining and fixing to a predetermined part in the room light, replacement and conversion can be easily performed by inserting the power feeding unit 11 into a predetermined mounting base in the existing vehicle room light room.

FIG. 1 is a schematic diagram showing the configuration of a specific example of a vehicle room light according to the present invention. FIG. 2 is a schematic view showing the configuration of another specific example of the vehicle room light according to the present invention. FIG. 3 is a diagram showing an example of the configuration of a high-power LED light-emitting element used in the present invention. FIG. 4 is a diagram illustrating a specific example of the configuration of the power feeding unit used in the present invention. FIG. 5 is a diagram showing a specific example of a wiring diagram of a vehicle room light according to the present invention. FIG. 6 is a schematic diagram showing the configuration of another specific example of the vehicle room light according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Board | substrate 3 High power LED light emitting element 4 Heat sink 5 Opening part 6 Electrode part 7 Wiring part 8 Drive wiring means 9 Connection wiring 10 Vehicle room light 11 Electric power feeding part 12 LED board 13 LED part 14 LED electrode part 15 Base part 16 Attaching Base 17 Current limiting resistance 20 Buffer material 21 Groove portion, recessed portion 22 Buffer material surface portion 23 Adhesive 24 Insulating resin 30 Opening portion 32 Conductive portion

Claims (18)

  The LED comprising a high-power LED light-emitting element mounted on a substrate and a heat-dissipating plate mainly composed of graphite having a perforated opening that exposes the LED light-emitting element, and the heat-radiating plate mounted on the substrate. A vehicle room light characterized in that the light emitting element is joined and arranged on the substrate so as to surround a peripheral portion of the light emitting element.   2. The vehicle room light according to claim 1, wherein a drive wiring means for the high-power LED light-emitting element is mounted on the substrate.   A plurality of the high-power LED light-emitting elements are arranged and mounted on the substrate at a predetermined interval, and the heat sink has a number of openings corresponding to the number of the high-power LED light-emitting elements. The vehicle room light according to claim 1, wherein the vehicle room light is provided.   4. The vehicle room light according to claim 1, wherein the heat radiating plate includes glass fiber in graphite.   The vehicle room light according to any one of claims 1 to 4, wherein the heat radiating plate has flexibility.   The vehicle room light according to claim 5, wherein the substrate has flexibility.   The vehicle room light according to any one of claims 1 to 6, wherein the high-power LED light-emitting element has an output of at least 1 watt or more.   The high-power LED light-emitting element is composed of a fine element substrate and an LED formed on one surface of the element substrate, and is different from the surface on the element substrate on which the LED is disposed. The vehicle room light according to any one of claims 1 to 7, wherein a wide electrode made of gold plating is disposed on the surface.   The high-power LED light-emitting element has a power feeding portion that can be inserted into a mounting base for an incandescent lamp of an existing vehicle room light that is connected through an appropriate connection line. The vehicle room light according to any one of claims 1 to 8.   The power supply part has the same outer shape as one type selected from either a pin ball type or a tube type in an incandescent bulb of an existing vehicle room light. The vehicle room light according to claim 9, wherein:   The power supply part of the high-power LED light-emitting element has a base part that has the same structure and the same size as an incandescent bulb of an existing vehicle room light and can be inserted into an existing mounting base, and between the base parts or The vehicle room light according to claim 9 or 10, wherein a current limiting resistor is provided in the base part.   The vehicle room light according to claim 11, wherein the current limiting resistance is a cement resistance.   The power connection portion of the high-power LED light-emitting element is maintained in the float state while one end of the current limiting resistor is connected to one base and the other end of the current limiting resistor is maintained in the float state. One electrode portion of the high-power LED light-emitting element is connected to the other end portion of the current-limiting resistor, and the other electrode portion of the high-power LED light-emitting element is connected to the other base. The vehicle room light according to claim 12,   The power connection portion of the high-power LED light emitting element is characterized in that a PPS resin is disposed between the pair of positive and negative electrode caps, and at least a part of the current limiting resistor is covered with the PPS resin. Item 14. A vehicle room light according to Item 13.   In the power connection portion of the high-power LED light emitting element, an opening is provided in a part of the PPS resin disposed between the pair of positive and negative electrode caps, and at least a part of the current limiting resistor is The vehicle room light according to claim 14, wherein the vehicle room light is exposed from a PPS resin.   The vehicle room light according to any one of claims 1 to 15, wherein the high-power LED light-emitting element has an output of at least 1 watt (w).   The vehicle room light according to any one of claims 1 to 15, wherein the high-power LED light-emitting element has an output of at least 2 watts (w).   The vehicle room light according to any one of claims 1 to 17, wherein a buffer material is provided on a peripheral portion of the substrate surface opposite to a surface on which the heat radiating plate is mounted.