JPH0460283B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle lamp that uses an LED as a light source and is used as a tail or stop lamp.

[Prior art] In general lighting equipment or display devices in which a plurality of LEDs are arranged horizontally as a light source, two lead frames are connected to one rectangular printed circuit board at appropriate intervals. The structure is such that an LED is attached to the lens, and a lens is attached to obtain a predetermined light distribution from the LED.

If an LED having such a configuration is used as a vehicle lamp such as a tail lamp or stop lamp, it is considered that the configuration shown in FIGS. 7 and 8 will be used. The lamp 1 in this case is an example of a tail lamp, and has, for example, a long rectangular shape in which eight LEDs 2 are arranged. these
The LEDs are each attached to a printed circuit board 5 via two lead frames 3 and 4, and the printed circuit board 5 is housed in a base 6 having a U-shaped cross section, and also has a long rectangular shape when viewed from the front. A lens 7 exhibiting a shape is attached to the opening of the base. The lens 7 is provided with a suitable lens cut 7a on the inside of the front side.

With this configuration, the light beam a on the front side emitted from each LED 2 is taken out to the outside through the lens cut 7a, and the area l when viewed from the front shines. Furthermore, since the light flux b emitted from each LED 2 to the side surface is directed only to the side surface of the lens 7, it cannot be seen from the front at all. Therefore, simply
Even if LEDs are used in this type of lighting, the range
Since only the part of the LED shines brightly, there arises the problem that not only is visibility poor, but also the utilization rate of the luminous flux generated from the LED is extremely poor.

There is an invention in an earlier application (Japanese Patent Application No. 59-270372) filed by the same applicant in order to increase the luminous flux utilization rate of LEDs.
This invention is excellent in that the luminous flux emitted from the side of the LED can be effectively used toward the front side. However, if the light emitting diode of this earlier application were to be used as is in the lamp shown in Fig. 7, the cap of each light emitting diode ( reflective members) are located adjacent to each other,
If there is a gap between adjacent pieces, it will cause looseness in the installed state, resulting in poor stability. Furthermore, if they are placed in close contact with each other without any gaps, the reflective members located at both ends will be pushed and returned by the reflective member located at the center due to expansion or contraction due to heat, causing the printed circuit board 4 and the lead frame to 2 and 3 may be damaged, or the reflective member located in the center may be pressed from both sides due to thermal expansion, causing internal distortion and putting pressure on the LED.
There is also a risk that the light emitting element and the wire may be damaged due to the internal strain.

[Problems to be Solved by the Invention] The present invention solves the visibility problem and the problem of luminous flux utilization rate that occur when LEDs are used as light sources for vehicle lights, and even when a reflective member is attached. , which attempts to solve problems caused by thermal expansion and contraction.

[Means for Solving the Problems] The present invention provides specific means for solving the above-mentioned problems by attaching a printed circuit board on which a plurality of LEDs are arranged horizontally to a base, and attaching a transparent reflective member to the LEDs. a lens is disposed on at least the front surface of the reflecting member, each of the reflecting members has a rectangular shape when viewed from the front, and has a cylindrical hole approximately in the center into which the LED fits; The back side is formed into a dome-shaped curved surface that reflects the emitted light emitted from the LED to the side into substantially parallel light rays toward the front,
The object of the present invention is to provide a vehicular lamp characterized in that each of the reflective members is arranged with a slight gap from each other, and each of the reflective members is connected with a flexible tape, By attaching a reflective member to each LED, the luminous flux emitted from the side of the LED can be used as a parallel ray toward the front side, increasing the effective luminous flux, which not only improves visibility but also improves the parallel By arranging the reflective members with appropriate gaps and adhering them with flexible tape, the influence of heat is absorbed and the arrangement becomes stable.

[Example] Next, the present invention will be explained in more detail with reference to an illustrated example. The illustrated lamp includes a plurality of (eight) LEDs.
This is an elongated tail lamp 11 when using a. Reference numeral 12 denotes an LED serving as a light source, and a commonly used LED is used as it is.
These LEDs 12 are connected to two lead frames 1 respectively.
3 and 14 to an elongated printed circuit board 15, and the printed circuit board has a U-shaped cross section.
Installed within 6. A lens 17 for a tail lamp is attached to the opening of this base, but prior to attaching the lens 17, each of the LEDs 12
A reflecting member 18 of the same type is attached to each.

The shape of the lens 17 is an elongated rectangle in front view suitable as a stop lamp, and a suitable concave lens cut 17a is provided on the inner surface.

The reflecting member 18 is made of, for example, transparent plastic or rubber, and has a rectangular shape when viewed from the front.
In this case, the square shape may be either a square or a rectangle, and it is sufficient that the square shape is formed so that a plurality of square lights can fit within the square lamp. Note that the reflecting members attached to each LED have substantially the same shape, so one of them will be explained.

The reflective member 18 has a square shape when viewed from the front,
There is a cylindrical hole 19 in the center that penetrates to the back side.
is provided, and the LED 12 is inserted into the hole and attached from the back side. Therefore, the hole 19 is formed so that its inner diameter substantially matches or is slightly larger than the outer diameter of the LED. The back side of the reflecting member 18 is formed into a dome-shaped curved surface 20 that reflects the luminous flux emitted from the attached LED 12 to the side surface toward the front side so as to become approximately parallel rays, and the dome-shaped curved surface 20 and the front surface A cut portion 21 is formed at the border between each side of the visual rectangle. Note that a wall portion 22 is provided along the outer peripheral edge of the hole 19 on the back side. Further, the lens cut 1 in the lens 17
Needless to say, the lens 7a is not limited to a concave lens, and a convex lens cut 17b can be provided as shown in FIG.

Each reflective member 18 having the structure specified in this way is
When attached to the LED 12, each LED is attached in parallel with the printed circuit board 15 at an appropriate interval as shown in FIG. 18, so that an appropriate gap 23 exists between adjacent ones. Each reflective member 18 arranged in parallel is covered with flexible tape 24, 2 from both sides of the parallel arrangement.
5 is attached by adhesive means, and each reflective member 1
8 are connected in series by tapes 24 and 25. In this case, the adhesive part is the cut part 2.
1 is the most effective. If the adhesive surfaces of the tapes 24 and 25 are also reflectively treated, a part of the luminous flux emitted from the LED 12 to the side surface will be reflected by the reflectively treated surfaces of the tapes 24 and 25.
Furthermore, luminous flux utilization is enhanced.

The vehicular lamp of the present invention having the above-mentioned configuration has a second
As shown in the figure and FIG. 3, the luminous flux a emitted from the LED 12 toward the front side passes through the hole 19 as it is, reaches the lens 17, and is taken out to the outside, and the luminous flux b toward the side surface is emitted from the reflecting member 18. The light is reflected by the curved surface 20 into substantially parallel light rays toward the front side, and is taken out through the lens 17 to the outside. Therefore, by using the reflecting member 18, almost all of the luminous flux emitted from the side of the LED, which is not generally used, can be reflected to the front side as parallel rays, so that the entire surface of the lens on the front side shines. The overall illuminance can be increased.

Furthermore, although a large number of reflective members 18 are arranged in parallel, each reflective member 18 has an appropriate gap 23 between adjacent reflective members, so that even if the reflective members 18 expand or contract due to the influence of heat, As a result, no interference occurs between the reflective members, and all of the light is absorbed by the flexible tapes 24 and 25. Each reflective member 18 is connected to the tape 24, 2.
Since the reflective members 18 are connected in a series, the individual reflective members 18 do not wobble and are arranged in a stable manner. In this case, as shown in FIG. 4, due to the presence of gaps 23 between adjacent reflecting members 18, dark areas A with narrow intervals are generated when the lens 17 is viewed from the front. Since the spacing appears narrower than the actual gap 23 provided between each adjacent space, it poses no problem in practice. The same applies to the case where the lens cut is a convex lens shown in FIG. Although the illustrated embodiment is a tail lamp, the same applies to other lamps.

[Effects of the Invention] As explained above, the vehicle lamp according to the present invention has a rectangular shape when viewed from the front, a dome-shaped curved surface on the back side, and a reflective member having a cylindrical hole in the center as an LED. By using the installed configuration,
In addition to the luminous flux emitted from the LED toward the front side, the luminous flux emitted from the side is also reflected by the curved surface into approximately parallel rays toward the front side and can be used as effective rays, so the utilization rate of the luminous flux is significantly improved, and the lighting Visibility can be improved by increasing the overall illuminance, and since multiple reflective members are arranged horizontally in parallel with appropriate gaps, even if there is expansion or contraction due to heat, it is possible to improve visibility. There is no interference between the reflectors, and there is no room for internal stress to occur due to the effects of heat, so not only will each part not be damaged, but all the reflective members are connected in a series with flexible tape, so there is no chance of rattling individually. This has the excellent effect of preventing this from occurring and stabilizing the mounting condition.

In addition, by forming the reflective member from a soft material such as rubber, the fitting state with the LED is stabilized, and
Furthermore, by applying a reflective treatment to the adhesive surface of the flexible tape that connects the reflective members at once, the utilization of luminous flux is further increased, and a substantially uniform luminous flux can be extracted from the entire front of the lamp, so that the irradiated surface of the lamp is illuminated over the whole area rather than in spots. It shines brightly and has various excellent effects such as improved visibility.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a vehicle lamp according to the present invention, FIG. 2 is a cross-sectional view taken along the - line in FIG. 1, and FIG. 3 is a cross-sectional view taken along the - line in FIG. Figure 4 is an enlarged sectional view of the part shown in Figure 3, Figure 5 is an enlarged sectional view similar to Figure 4 showing other lens cut parts, and Figure 6 is an exploded view of the main parts of the lamp. The partial perspective view shown in Figure 7 is a typical
The first case when LED is arranged in the same lighting device as the present invention
FIG. 8 is a front view similar to the figure, and FIG. 8 is a sectional view taken along the - line in FIG. 7. 11...Lighting equipment, 12...LED, 13,14...
... Lead frame, 15 ... Printed circuit board, 16
... Base, 17 ... Lens, 17a ... Lens cut, 18 ... Reflection member, 19 ... Hole, 20 ...
...Dome-shaped curved surface, 21...Cut part, 22...
Wall portion, 23... Gap, 24, 25... Flexible tape.

Claims (1)

[Claims] 1. A printed circuit board on which a plurality of LEDs are laterally arranged is attached to a base, a transparent reflective member is attached to each of the LEDs, and a lens is disposed at least in front of the reflective member, Each of the reflecting members has a rectangular shape when viewed from the front, and has a cylindrical hole approximately in the center into which the LED fits, and the rear side has a cylindrical hole into which the LED fits.
It is formed into a dome-shaped curved surface that reflects the emitted light emitted from the side from the LED toward the front into approximately parallel light beams, and each of the reflecting members is arranged with a slight gap from each other, and each reflecting member is flexible. A vehicle lamp characterized by being connected with adhesive tape. 2. The vehicle lamp according to item 1, wherein the flexible tape has an adhesive surface, and the adhesive surface is subjected to a reflective treatment.