JP3527178B2 - LED unit for signal lights - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LED unit used in a three-color signal light device or the like.

[0002]

2. Description of the Related Art Conventionally, an incandescent light bulb (light source), a reflector arranged on the back side of the incandescent light bulb, and a front side of the incandescent light bulb have been conventionally used as a three-color signal lamp installed on a road or the like. It is composed of a front cover and a structure in which the red, blue and yellow signal colors are colored on the front cover.

Recently, LED signal lamps have been put into practical use for the purpose of reducing power consumption and reducing the time required for maintenance and management.

The LED type signal lamp uses as its light source an LED unit in which a large number of LED lamps (emission color: red, blue or yellow) are mounted on a printed wiring board, and the LED units are housed in a lamp case. The front side of the LED lamp group is covered with a transparent front cover.

As a signal light device using the LED unit as a light source, in addition to the three-color signal light device, for example, an LED type arrow light device, a single flashing light device, etc. have been put to practical use.

[0006]

By the way, the conventional LE
According to the D type signal light device, a glass epoxy board is used as a printed wiring board, and the LED lamp mounted on the glass epoxy board is directly exposed to the outside through a transparent front cover. Therefore, when the signal lamp is exposed to sunlight, the sunlight enters the lamp through the front cover, directly hits the glass epoxy substrate, and is reflected by the substrate surface or the copper foil pattern on the surface, and then again. It passes through the front cover and exits.

When the sunlight hits the glass epoxy substrate and is reflected in this way, it becomes difficult to see the light emitted from the LED lamp. In particular, when a strong light such as the sun shines, the influence of the reflected light becomes large and it becomes difficult to visually recognize the signal lamp display.

The present invention has been made in view of such circumstances, and an LED unit for a signal lamp, which is less affected by reflected light and can secure good visibility even when exposed to strong light such as the sun. For the purpose of providing.

[0009]

An LED unit according to the present invention is an LED unit used in a signal lamp, and includes a plurality of LED lamps mounted on a substrate and respective LEDs thereof.
It is equipped with a light shield plate with through holes formed at positions corresponding to the lamps, and the light shield plate is placed near the tip of the LED lamp.
In addition, the center of each through hole of the light shielding plate is
It is characterized by being eccentric downwards with respect to the center of the LED lamp .

When the LED unit of the present invention is applied to a signal lamp, even if sunlight is incident on the signal lamp, the sunlight is blocked by the light-shielding plate in front of the substrate, so that the sunlight directly hits the substrate. It can be prevented and the influence of reflected light can be significantly reduced. In addition, for each through hole of the light shield
The center is below the center of each LED lamp.
Since it is arranged so as to be eccentric to the lower side (when installed), L
The sun traveling from above with respect to the optical axis of the ED lamp
Of light (especially Nishinichi etc.), it is incident on an LED lamp and reflected.
It is possible to reduce the sunlight hitting the plate etc. (See Fig. 5)
See). In addition, below the center position of the through hole with respect to the lamp center
The appropriate amount of eccentricity toward one side is in the range of 0.1 mm to 5 mm.
Is.

In the LED unit of the present invention, if a black matte coating is applied to the front side of the light shielding plate, the light hitting the light shielding plate is absorbed, and the antireflection effect can be enhanced. Furthermore, if black matte coating is applied to both sides of the shading plate, even if sunlight enters through the through holes and is reflected by the printed wiring board, the reflected light is absorbed by the back surface of the shading plate. The antireflection effect can be further enhanced.

[0012]

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view schematically showing the structure of an embodiment of the present invention, and FIG. 2 is a front view of the embodiment. Figure 3
4 and FIG. 4 are a sectional view and a front view, respectively, showing the main structure of the embodiment of the present invention.

The LED unit 10 of this example is a unit applied to a three-color signal lamp, and includes a large number of LED lamps (emission color: red, blue or yellow) mounted on a printed wiring board (glass epoxy board) 2. ) 1, ..., and the drive board 3 and the power supply section 4 arranged on the back surface side of the printed wiring board 2.
And the light shielding plate 5 and the like arranged in front of the printed wiring board 2. The printed wiring board 2 is held by the light shielding plate 5 via the spacer 6.

The LED unit 10 is housed in a lamp case 21 of the signal lamp 20, and its front side is covered with a transparent front cover 22. At the rear center of the lamp case 21,
A connector 23 for connecting to the drive board 3 is arranged. The LED unit 10 includes the light shielding plate 5 and the lamp case 21.
The entire unit is held by the lamp case 21 by being fixed to the peripheral portion of the front side of the lamp via the packing 7 or the like. The printed wiring board 2 is provided with support legs 8 at appropriate positions.

As shown in FIG. 3, the LED lamp 1 is provided with a reflection dish 12 provided at the tip of a lead frame 13 and an LED chip 11 die-bonded to the bottom surface of the reflection dish 12. The electrode on the opposite side of the LED chip 11 is connected to the tip of the other lead frame 14 via a conductive wire 15, and these LED chip 11, reflecting dish 12, conductive wire 15 and lead frames 13, 14 are connected. The tip portion of is molded (resin-sealed) with epoxy resin 16 (translucent resin). In addition,
The epoxy resin 16 plays a role of protecting the LED chip 11 and the like and a condenser lens and the like.

The light shielding plate 5 is a processed product of a steel plate such as SPCC (cold rolled steel plate), and is an L mounted on the printed wiring board 2.
Through holes (circles) 5a ... 5a having a diameter larger than the lamp diameter are formed at positions corresponding to the ED lamps 1. A black matte coating is applied to the entire surface (both the front surface 5b and the back surface 5c) of the light shielding plate 5.

The distance D between the light shield plate 5 and the printed wiring board 2 is defined by the spacer 6, and the front surface 5b is arranged so as to be flush with the tip of the LED lamp 1. Further, the light shielding plate 5 is arranged so as to be shifted downward (downward when the signal light device 20 is installed) with respect to the entire LED lamps 1 ... 1 so that the center of the through hole 5a is the LED.
It is eccentric downward with respect to the center of the lamp 1.

In the present embodiment, the diameter of the through hole 5a of the light shielding plate 5 and the positional relationship between the through hole 5a and the LED lamp 1 are determined by the visual range of the signal lamp 20 (± 33 degrees with respect to the horizontal direction, It is set so that it is possible to secure 33 degrees to the downward direction.

Specifically, the diameter of the LED lamp 1 is φ.
When the diameter is 7.5 mm, the diameter of the through hole 5a is 10 mm to
The eccentric amount e (FIG. 4) of the center of the through hole 5a with respect to the center of the LED lamp 1 is set to 1.3 mm to 1.6 mm. Further, when the diameter of the LED lamp 1 is φ5 mm, the diameter of the through hole 5a is 10 mm to 11 mm,
The eccentric amount e of the center of the through hole 5a with respect to the center of the lamp 1 is set to 2 mm to 4.2 mm. The distance D (FIG. 3) between the light shielding plate 5 and the printed wiring board 2 is preferably about 12 mm to 14 mm, although it depends on the size of the LED lamp 1.

Next, the operation of this embodiment will be described with reference to FIG.

First, as shown in FIG. 5 (B), in the conventional LED unit 110 for a signal lamp, when sunlight (especially the sun) is incident on the signal lamp (not shown), the incident light is printed wiring board. Since the light is reflected by 2 and emitted toward the visible range of the signal lamp, the light emission of the LED unit 110 becomes difficult to see. Further, when sunlight enters the LED lamp 1, the reflection dish 12 around the LED chip 11 shines, so that it is difficult to visually recognize whether the LED lamp 1 is in a lighting state or a non-lighting state.

On the other hand, in the present embodiment, as shown in FIG.
As shown in FIG. 3, even if sunlight is incident on the optical axis of the LED lamp 1 from above, most of the incident light is blocked by the light shielding plate 5, so that the printed wiring board 2 is directly exposed to the sunlight. And the reflected light emitted toward the visible range of the signal light device can be significantly reduced.

Moreover, the center of the through hole 5a of the light shielding plate 5 is L
Since it is eccentric downward with respect to the center of the ED lamp 1,
Of the sunlight that is traveling from above with respect to the optical axis of the LED lamp 1, the angle range of the sunlight that is incident on the LED lamp 1 and directly strikes the reflection dish 12 is conventionally (FIG. 5 (B)). On the other hand, it can be narrowed. This makes it possible to shorten the time period in which the sun and the like directly hit the reflection plate 12 of the LED lamp 1 as compared with the conventional case, and further improve the visibility.

Further, in this embodiment, the back surface 5 of the light shielding plate 5 is used.
Since black matte coating is also applied to c, even if sunlight is incident through the through hole 5a of the light shielding plate 5 and reflected by the printed wiring board 2, the reflected light is the back surface 5c of the light shielding plate 5.
Absorbed by. Accordingly, it is possible to prevent reflected light, which is repeatedly reflected between the front surface of the printed wiring board 2 and the back surface 5c of the light shielding plate 5, from exiting from the through hole 5a toward the visible range.

[0027]

In the above embodiment, the example of the LED unit used in the three-color signal lamp is described, but the present invention is not limited to this, and may be, for example, an LED type arrow lamp or a single flashing lamp. It can also be applied to other signal lights.

[0029]

As described above, according to the LED unit of the present invention, the light shielding plate having the through holes formed at the positions corresponding to the respective LED lamps mounted on the board is arranged in front of the board. Therefore, it is possible to prevent sunlight from directly hitting the substrate. Therefore, when the LED unit of the present invention is applied to the signal light device, even if the signal light device is exposed to strong light such as the sun, it is possible to reduce the influence of the reflected light and ensure good visibility.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a structure of an embodiment of the present invention.

FIG. 2 is a front view of an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a main structure of an embodiment of the present invention.

FIG. 4 is a front view showing a main part structure of the embodiment of the present invention.

FIG. 5 is an explanatory view of the operation of the embodiment of the present invention.

[Explanation of symbols]

10 LED unit 1 LED lamp 11 LED chips 12 Reflection dish 2 printed wiring board 3 drive board 4 power supply 5 Light shield 5a through hole 6 spacers 20 signal lights 21 Lamp case 22 Front cover 23 Connector

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F21S 2/00 F21S 8/04 H01L 33/00 F21Y 101: 02

Claims (2)

(57) [Claims] 1. A LED unit used in the signal lamp device, a plurality of LED lamps mounted on the substrate, its
A light-shielding plate having through holes formed at positions corresponding to the respective LED lamps, and the light-shielding plate is provided near the tip of the LED lamp.
The center of each through hole of the light shielding plate that is arranged
Is eccentric downward with respect to the center of each LED lamp . 2. The LED unit for a signal lamp according to claim 1, wherein at least a front surface side of the light shielding plate is coated with black matte coating.