JPH0371724B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle lamp that uses a light emitting diode as a light source, and is improved in particular to prevent a decrease in the amount of light due to heat generation during light emission.

[Conventional technology]

In recent years, with the development of semiconductor technology, high-brightness light-emitting diodes have been developed, and they have become available at low prices.As a result, light-emitting diodes with high brightness have become available in vehicle lights, such as brake lights, taillights, and even on the outside of the rear of the car body, commonly known as high mounts. It is being considered as a light source for lighting devices called Stotsu lamps. The main reason for this is that, in addition to the fact that high-brightness products are now available at low prices, unlike regular light bulbs, they do not have a filament, so they have a semi-permanent lifespan. There are no restrictions on the light fixture itself and its mounting location, and the light fixture can be made thinner and installation processing is easy.
This is because it has many excellent features, such as generating significantly less heat than light bulbs and being able to be made smaller, and can be said to point to the direction of future lighting equipment.

[Problem that the invention seeks to solve]

However, although light emitting diodes generate far less heat than ordinary light bulbs, when large-sized lamps with hundreds of units are used, heat generation from the diodes themselves and the resistors used to light the diodes becomes a problem. That is, when the amount of heat generated increases and the temperature inside the lamp rises, there is a problem that the luminous efficiency decreases and the lamp becomes dark, and therefore it is necessary to take appropriate heat dissipation measures.

[Means for solving problems]

The vehicle lamp according to the present invention has been developed in view of the above-mentioned points, and is mounted on the outside of the rear of the vehicle body, with a large number of light emitting diodes mounted on the surface of the board, and a resistor for lighting the diodes mounted on the back surface. The lamp is a lamp in which at least the diode lighting resistor is molded with resin, and the lamp body is provided with an air hole for taking in outside air and a drainage hole.

[Effect]

In the present invention, the heat generated by the diode lighting resistor is transmitted to the lamp body via the resin, and air is taken in through the air holes for air cooling, so the heat dissipation effect is large and a decrease in the light intensity of the light emitting diode is prevented.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention applied to a high-mounted stop lamp, and FIG. 2 is an external perspective view of an automobile equipped with the same lamp.
In these figures, 1 is the rear outside of the car 2,
For example, a high-mounted stop lamp is installed at the center of the upper part of a rear window 3, and this lamp 1 includes a box-shaped lamp body 4 that opens toward the rear of the vehicle body, a lens 5 that closes the opening of this lamp body 4, and a lamp body that Board (printed circuit board) arranged in 4
6 and a lens body 7, a large number of light emitting diodes 8 mounted in a matrix at predetermined intervals on the surface of the substrate 6, a diode lighting resistor 9 disposed on the back surface of the substrate 6, and this resistor 9. It is generally composed of resin 10 and the like to be molded.

The lamp body 4 is made of a material with excellent heat dissipation properties, such as aluminum, and is fixed to the frame 11 of the rear window 3 via mounting bolts 12 and nuts 13, and has a large surface area on its top and back surfaces. In order to increase the heat dissipation effect, sawtooth-like uneven parts 14 and 15 are formed respectively, and an air hole 16 for taking in outside air is formed at the upper part of the back surface, and a drainage hole 17 is formed on the lower surface near the front of the vehicle body. .

The lens 5 is made of a red-colored translucent resin or glass, and has a large number of small convex lenses 18 densely formed on its inner surface.
The lens body 7 and the lens body 7 are hermetically fitted and fixed into the opening of the lamp body 4. The lens body 7 is made of transparent synthetic resin such as acrylic resin,
It is disposed between the substrate 6 and the lens 5, and as shown in FIG. It is formed in one piece.
The condensing lens 20 is composed of a hemispherical spherical lens having a substantially rectangular outline at the bottom, and the light emitting diode 8 is located at or near the focal point of the condensing lens 20, thereby concentrating the light from the diode 8. The light is focused and guided to the lens 5.

The resin 10 is made of a resin having excellent heat conductivity such as epoxy resin, and covers the entire back surface of the diode lighting resistor 9 and the substrate 6. A space 21 is formed inside the resin 10 and the lamp body 4, and outside air is introduced into this space 21 through the air hole 16 and discharged through the drain hole 17. Also, air hole 1
Rainwater entering from 6 is also drained from the drainage hole 17.

Thus, according to the high mount stop lamp 1 having such a configuration, the heat generated by the diode lighting resistor 9 during lighting is transmitted to the lamp body 4 via the resin 10, and the heat is radiated from the entire surface of the lamp body 4. Since outside air is taken in through the hole 16 and the resin 10 is air-cooled, the heat dissipation effect is much greater than that of a conventional lamp in which the diode lighting resistor 9 is simply mounted on the back surface of the substrate 6. Therefore, there is little influence on the light emitting diode 8, a decrease in luminous efficiency is prevented, and the lens 5 can be always illuminated with constant brightness.

Further, since the diode lighting resistor 9 is molded with the resin 10, it has excellent water resistance and vibration resistance, and improves the durability of the lamp.

In addition, unlike brake lights and tail lights 25, the high-mounted stop light 1 is usually installed near the driver's eye level, and is brightly lit together with the brake lights when braking, so it alerts drivers of following vehicles. It can be made even more exciting. Therefore, it is highly effective in preventing rear-end collisions and ensuring road traffic safety.

Note that if a water infiltration prevention wall 27 is provided at the inner opening of the air hole 16, the intrusion of rainwater from the hole 16 can be further reduced, and the drainage hole 17 can be formed into a substantially crank-shaped (〓) shape. If formed, it is possible to prevent water from entering from the lower part of the lamp body 4 during car washing or the like.

FIG. 4 is a sectional view of a main part showing another embodiment of the present invention. In this embodiment, not only the diode lighting resistor 9 but also a part of each light emitting diode 8 is made of resin 1.
0, so that the heat of each light emitting diode 8 is released to the lamp body 4 through the resin 10, and sawtooth-like unevenness 3 is formed on the surface of the resin 10 on the space 21 side.
0 to increase the surface area, and an opening 32 having a ridge 31 at the front end of the vehicle body is formed on the upper surface of the lamp body 4, and this opening 32 is connected to a lid member having a substantially U-shaped cross section. 33, and the lid member 33 and the ridge 31 form a maze-like passage 35 that prevents rainwater from entering. An air hole 16 communicating with the space 21 is formed in the lower horizontal portion 33A of the lid member 33. Further, the upper surface of the upper horizontal portion 33B of the lid member 33 is inclined so that the thickness of the horizontal portion 33B gradually increases toward the rear of the vehicle body. Note that the other configurations are almost the same as those of the above embodiment.

With such a configuration, the heat generated by the light emitting diode 8 itself is transmitted to the lamp body 4 via the resin 10, so it is clear that a lamp with even better heat dissipation effect can be provided.

In the embodiment shown in FIG. 1, the case where the lens body 7 is disposed in the lamp body 4 has been explained.
The present invention is not limited to this, and it goes without saying that the lens body 7 may not be used.

It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, as shown in FIG.
An intake fan 40 may be provided corresponding to the air hole 16, or an exhaust fan 41 may be provided corresponding to the drain port 17 as shown by the chain line to forcibly dissipate heat and enhance the heat dissipation effect. .

〔Effect of the invention〕

As explained above, in the vehicle lamp according to the present invention, at least the diode lighting resistor disposed on the back surface of the substrate is molded with resin, and the heat of the resistor is transferred to the lamp body via the resin. Since air is taken in through the air hole provided in the lamp body and the resin is air-cooled, the heat generated by the resistor can be effectively dissipated. Therefore,
It has almost no effect on the light emitting diodes and prevents a drop in luminous efficiency, and the resistor for lighting the diodes has good water resistance and vibration resistance, especially for large lighting fixtures that use a large number of light emitting diodes and are installed outside the vehicle body. It is suitable.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
The figure is an external perspective view of a car equipped with the lighting device of the present invention.
3 is a perspective view of a lens body, FIG. 4 is a sectional view of a main part showing another embodiment of the invention, and FIG. 5 is a sectional view of a main part showing still another embodiment of the invention. 1... High mount stop lamp, 4... Lighting body, 5... Lens, 6... Board, 7... Lens body, 8
...Light emitting diode, 9...Resistor for diode lighting, 10...Resin, 16...Air hole, 17...Drain hole.

Claims (1)

[Claims] 1. A light body installed on the outside of the rear of the vehicle body,
A lens that closes the front opening of the lamp body, a substrate disposed within the lamp body with a large number of light emitting diodes mounted on the front surface, and a diode lighting resistor mounted on the back surface, and at least the diode lighting resistor mounted on the substrate. 1. A vehicular lamp, characterized in that the lamp body is provided with an air hole for introducing outside air into a space between the lamp body and the resin, and a drainage hole.