JP3493630B2 - LED traffic light fixture - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traffic signal lamp used for road signals, railway signals, etc. More specifically, a plurality of LED lamps are used as a light source,
For example, the present invention relates to a traffic signal lamp that reduces the probability of non-lighting accidents due to filament breakage to further improve reliability, and simplifies maintenance due to the improved reliability to reduce running costs. It is a thing.

[0002]

2. Description of the Related Art FIG. 8 shows an example of the structure of a conventional traffic signal lamp 90 of this type.
0 is an outer lens 91, an inner lens 92, and L
The light source board 94 is provided with a plurality of ED lamps 93 attached. In the actual traffic signal lamp 90, a housing, a power supply device for lighting the LED lamp, and the like are also included, but since they are not the gist of the present invention, illustration and description thereof will be omitted.

The outer lens 91 is provided with a diffusing lens cut 91a for diffusing light in a horizontal direction and a downward direction when the traffic signal lamp 90 is installed. A light distribution characteristic to be formed. Further, the inner lens 92 has a Fresnel lens shape with a converging lens cut 92a for converging the light from the LED lamp 93 into substantially parallel rays, and makes the outer lens 91 incident.

At this time, the LED lamp 93 which is the light source
Are mounted on the light source substrate 94 and have an area. Therefore, the focal length f of the converging lens cut 92a is set so that the area where the LED lamps 93 are arranged falls within a conical range connecting the outer circumference and the focal point f of the inner lens 92, and the outer lens 91 is formed. The light incident on is brought close to parallel rays so that the brightness of the surface of the outer lens 91 becomes uniform. Further, the diffusion lens cuts 91a provided on the outer lens 91 have, for example, a convex lens shape and the like having the same curvature, so that the above-described operation of making the outer lens 91 surface uniform in brightness is further ensured. I am supposed to.

[0005]

However, in the traffic signal lamp 90 having the above-described conventional structure, the inner lens 92 having the above-described structure can surely make the brightness of the surface of the outer lens 91 uniform. However, on the other hand, all the LED lamps 9 are
No. 3 is not in the focus position, so-called out-of-focus condition occurs, and the light collection rate is reduced to become a dark traffic signal lamp 90. In order to satisfy the central brightness required for this type of traffic signal lamp 90, an LED lamp is required. The number of 93s to be used must be increased, which causes a problem such as an increase in cost.

Also, on the outer lens 91 side,
Since the diffusing lens cuts 91a are all of the same curvature having a sufficient diffusing angle to form the light distribution characteristic, the diffusing angle tends to be too wide, and like the case of the inner lens 92 described above. The central illuminance tends to be insufficient, and the number of LED lamps 93 to be used must be increased more and more.

[0007]

As a concrete means for solving the above-mentioned conventional problems, the present invention makes an outer lens for forming a light distribution, and makes light incident on the outer lens as substantially parallel rays. In the LED traffic signal lamp including an inner lens in the form of a Fresnel lens and a plurality of LED lamps arranged on the light source substrate with a predetermined area, the focus of the inner lens is on the center line of the inner lens. To be done, and
On the outer circumference of the inner lens, a distance to a position where an extension of a line connecting the outer circumference of the inner lens and an LED lamp provided at an outer end of the light source substrate intersects with the center line is defined as a focal length, At the center of the inner lens,
The distance from the inner lens to the LED lamp provided at the center on the light source substrate is defined as the focal length, and at the intermediate position between the outer circumference and the center, the intermediate distance between the focal lengths set at the outer circumference and the center is set stepwise. Alternatively, the focal length is changed in a gradual manner, and the LED traffic signal lamp and / or the outer lens surface is sectioned in a substantially grid pattern, and a light distribution characteristic is formed in each of the sections. In the LED traffic signal lamp which is provided with a diffusion lens cut for achieving the above, the diffusion lens cut includes a narrow-angle diffusion lens cut mainly responsible for light distribution in the front direction of the lamp as a relatively narrow diffusion angle, At least two types of wide angle diffusion lens cuts, which are mainly responsible for general light distribution, are prepared as diffusion angles wider than the narrow angle diffusion lens cut. Comprising type diffusion lens cut is intended to solve the problems by providing an LED traffic signal lamp, characterized in that it is arranged so as to be alternately repeated.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on the embodiments shown in the drawings. 1 shows a first embodiment of an LED traffic signal lamp 1 according to the present invention. The LED traffic signal lamp 1 has an outer lens 2, an inner lens 3, and a light source substrate 4 having a light distribution characteristic. A plurality of LED lamps 5 mounted in an appropriate arrangement in consideration
It is similar to that of the conventional example in that it is composed of.

Also in the LED traffic signal lamp 1 of the present invention, the outer lens 2 is provided with the lens cut 2a to form an appropriate light distribution characteristic as the traffic signal lamp, and the inner lens 3 is A Fresnel lens cut 3a is provided, and the purpose is to allow the amount of light emitted from the LED lamp 5 to the outer lens 2 to enter the outer lens 2 in a state where light distribution characteristics are easily formed. It is the same.

Here, FIG. 2 shows an example of the light distribution characteristic D (luminance standard) required for this type of LED traffic signal lamp in Japan. By optimizing the Fresnel lens cut 3a provided on the inner lens 3, the brightness of the light distribution characteristic formed by the outer lens 2 is further improved.

First, referring to FIG. 2, in the light distribution characteristic D, the front direction (horizontal direction H and vertical direction V are both 0 °,
That is, it can be seen that a light intensity of 288 cd, which is a position on the extension of the center line Z of the LED traffic signal lamp 1, which is relatively high compared to other portions, is required. Therefore, in the present invention, in order to secure this central luminous intensity, parallel light rays are made incident in the vicinity of the center line Z of the outer lens 2 in which light is most easily distributed in the front direction.

That is, in the present invention, the Fresnel lens cut 3a of the inner lens 3 has a focal point f1 on the LED lamp 5 in the portion near the center line Z as shown in FIG. It is assumed that parallel rays are made incident near the center line Z of the outer lens 2. It should be noted that the arrangement density of the LED lamps 5 in the vicinity of the center line Z of the light source substrate 4 can be increased if necessary.

By doing so, the central luminous intensity is certainly satisfied, but on the other hand, when the outer lens 2 at the time of lighting is viewed from the outside, only the central portion shines brightly and the outer lens 2 The display quality of the LED traffic signal lamp 1 that displays a signal with the light emission state over the entire surface is impaired.

In view of the above state, in the present invention, on the outer circumference of the inner lens 3, the LED lamps 5 provided on the outer circumference of the inner lens 3 and the outer end of the light source substrate 4.
The focal length f3 is defined as the distance to the position where the extension of the line connecting with and intersects with the center line Z. At this time, the LED lamp 5 to be connected to the outer circumference of the inner lens 3 is basically the most center line Z on the light source substrate 4.
Although the LED lamp 5 located at a distance far from is selected, the LED lamp 5 located farthest from the LED lamp 5 can be freely selected depending on the necessity of forming the light distribution characteristics or the necessity of adjusting the appearance.

In the present invention, the focal length f1
Is set to the Fresnel lens cut 3a near the center line Z of the inner lens 3 and the Fresnel lens cut 3a near the outer periphery where the focal length f3 is set. Distance f
A focal length f2 that is an intermediate value between 1 and the focal length f3 is set.

At this time, as shown in FIG. 1, the inner lens 3 is appropriately divided into, for example, a central portion 31, an intermediate portion 32, and an outer peripheral portion 33, and a focal length f1 is set in the central portion 31. The focal length f2 may be set in the intermediate portion 32, and the focal length f3 may be set in the outer peripheral portion 33, or the focal length f2 of the intermediate portion 32 may be changed stepwise. , The focal length f1 of the central portion 31
To a focal length f3 of the outer peripheral portion 33, the value may be gradually changed so as to gradually increase.

With the above construction, the LE of the present invention can be obtained.
In the D traffic signal lamp 1, no noticeable light unevenness was felt on the surface of the outer lens 2 at the time of lighting, and the central luminous intensity was also improved. Comparing this with the number of LED lamps 5 for obtaining the same central luminous intensity, it is 20 when the inner lens having the single focal length of the conventional example is adopted.
While it required ~ 25 LED lamps 5,
With the configuration of the inner lens 3 having a variable focal length according to the present invention, 16 lenses are sufficient, and it is confirmed that the efficiency is improved by 20% or more.

In addition, the inventor has also realized the uniform brightness of the surface of the outer lens 2 and the light source efficiency when obtaining the light distribution characteristic D in the structure of the outer lens 2 as in the case of the inner lens 3 described above. The improvement, that is, the reduction in the required number of LED lamps 5 was examined as described below as the second embodiment of the present invention.

Here, in the second embodiment, the diffusion lens cut 2a provided on the outer lens 2 is divided into a narrow angle diffusion lens cut 21 and a wide angle diffusion lens cut 22 as shown in an enlarged view in FIG. First, the narrow-angle diffusion lens cut 21 has a relatively narrow diffusion angle in the front direction of the LED traffic signal lamp 1, that is, in the central axis X direction as shown in FIG. In the embodiment, it has a light distribution characteristic Hn that radiates light vertically 5 ° vertically and horizontally 10 ° horizontally.

As shown in FIG. 5, the wide-angle diffusing lens cut 22 has a relatively wide diverging angle (in this embodiment, vertical 5 ° to lower 33 ° and horizontal 33 ° to the left and right). ), The light distribution characteristic Hw is set so as to emit light. As is clear from the above figures and description, since the light distribution characteristic Hw has an asymmetric angle with respect to the central axis X in the vertical direction, the wide angle diffusion lens cut 22 has the prism portion 23. It is provided to refract the light incident from the inner lens 3 downward as appropriate.

The prism portion 23 is not always necessary when the light source has a sufficient light amount such as an incandescent lamp, but the LED lamp 4 having a small absolute light amount as in the present invention is adopted as the light source. In this case, it is extremely effective in reducing the cost of the LED traffic signal lamp 1 since it is possible to cope with the prescribed light distribution characteristic D with a smaller number of LED lamps 5.

In the present invention, the outer lens 2 is used.
The arrangement of the narrow-angle diffusing lens cut 21 and the wide-angle lens cut 22 on the surface is also defined as shown in FIG. 6, that is, for example, in the form of vertical and horizontal grids each having a side of about 4 mm. The narrow-angle diffuser lens cuts 21 and the wide-angle diffuser lens cuts 22 are alternately arranged in the vertical and horizontal directions with respect to the section 2b. In FIG. 6, the symbol N is used for the narrow angle diffusing lens cut 21 and the symbol W is used for the wide angle diffusing lens cut 22 to simplify the display.

In the above, the diffusion lens cut 2a is
Narrow angle lens cut 21 and wide angle diffusion lens cut 22
However, the present invention is not limited to this. For example, the narrow angle lens cut 21 and the wide angle diffusion lens cut 21 may be provided depending on the convenience of forming the light distribution characteristic D. It is also possible to provide a medium-angle diffusion cut having a diffusion angle intermediate to that of 22, and for example, the medium-angle diffusion cut may have a plurality of diffusion angles.

Here, considering the use situation of the LED traffic signal light fixture 1, when a viewer actually sees the LED traffic signal light fixture 1 installed on the road or the like, for example, a position at a distance of 10 m or more is used. Is to be visually inspected from
Since the LED traffic signal lamp 1 is installed at a height of about 4.5 m above the ground, no visual observation is made from a close range.

Therefore, the viewer does not recognize the individual sections 2b even when visually observing the surface of the outer lens 2 in the lit state, and the entire surface of the outer lens 2 emits light with uniform brightness. It will be recognized as.
Therefore, in the LED traffic signal lamp 1 having the configuration of the present invention, it is possible to simultaneously form the light distribution characteristic D (see FIG. 2) and improve the appearance of the outer lens 2 at the time of lighting.

FIG. 7 shows an LED traffic light 1 according to the present invention.
In the second embodiment, the narrow-angle lens cut 21 and the wide-angle lens cut 22 are both formed in a convex lens shape. However, in the third embodiment, The narrow angle diffusing lens cut 24, which has a low diffusivity, is formed as a concave lens.

Even when the convex lens shape is changed to the concave lens shape as described above, the light distribution characteristics Hn shown in FIG. 4 are the same, and the outer lens 2 is provided in a grid pattern. In the vertical section 2b, both vertically and horizontally,
Similar to the previous embodiment, the narrow angle diffuser lens cuts 24 and the wide angle diffuser lens cuts 22 are arranged alternately.

By doing so, in the LED traffic signal lamp 1 according to the third embodiment, it may occur on the surface of the outer lens 2 at the time of lighting, depending on the distance when viewed or the position (angle). It was confirmed that it was possible to prevent the occurrence of moire (interference pattern).

As is clear from the above description, the object of the present invention is to satisfy the light distribution characteristic D with a smaller number of LED lamps 4 in both the first embodiment, the second embodiment and the third embodiment. At the same time, the surface of the outer lens 2 is made to shine uniformly and the display quality is improved. Therefore, in actual implementation, the first embodiment-
Only one of the third embodiments may be applied, or the combination of the first embodiment and the second embodiment or the combination of the first embodiment and the third embodiment may be applied. It is a good one.

[0030]

As described above, according to the present invention, the outer lens for forming the light distribution, and the Fresnel lens-shaped inner lens for making the light incident on the outer lens as substantially parallel rays, In an LED traffic signal lamp including a plurality of LED lamps arranged on a light source substrate with a predetermined area, the focus of the inner lens is located on the center line of the inner lens, and the outer periphery of the inner lens is Then, the L provided on the outer periphery of the inner lens and the outer end of the light source substrate.
The focal length is the distance to the position where the extension of the line connecting to the ED lamp intersects the center line, and at the center of the inner lens, the distance from this inner lens to the LED lamp provided at the center on the light source substrate is set. The distance is defined as a focal length, and at an intermediate position between the outer circumference and the center, an LED traffic signal lamp in which the focal length is changed stepwise or gradually as an intermediate value of both focal lengths set on the outer circumference and the center, Alternatively, the outer lens surface is divided into a substantially grid pattern,
In an LED traffic signal lamp in which each of the sections is provided with a diffusion lens cut for forming a light distribution characteristic, the diffusion lens cut has a relatively narrow diffusion angle mainly in the front direction of the lamp. At least two types are prepared: a narrow-angle diffuser lens cut that takes charge of light and a wide-angle diffuser lens cut that mainly takes charge of general light distribution as a spread angle wider than the narrow-angle diffuser lens cut.
The LED traffic signal lighting device is characterized in that different types of diffuser lens cuts are arranged alternately so that uniform brightness can be obtained when the outer lens surface is lit and the front surface LEDs with less bright light distribution characteristics that satisfy the regulations in the direction
It can be obtained by the number of lamps, and it is possible to reduce the power consumption of this type of LED traffic signal lighting fixture, which has an extremely excellent effect on performance improvement, and also has an extremely excellent effect on cost reduction.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of an LED traffic signal lamp according to the present invention.

FIG. 2 is an explanatory diagram showing a light distribution characteristic required for an LED traffic signal lamp of this type.

FIG. 3 is a cross-sectional view showing a second embodiment of an LED traffic signal lamp according to the present invention as a main part.

FIG. 4 is an explanatory diagram showing an example of a light distribution characteristic set for a narrow angle diffusion lens cut.

FIG. 5 is an explanatory diagram showing an example of a light distribution characteristic set to a wide angle diffusion lens cut.

FIG. 6 is an explanatory diagram showing an example of the arrangement of a narrow-angle diffuser lens cut and a wide-angle diffuser lens cut on the outer lens surface.

FIG. 7 is a cross-sectional view showing an essential part of a third embodiment of the LED traffic signal lamp according to the present invention.

FIG. 8 is a sectional view showing a conventional example.

[Explanation of symbols]

1 ... LED traffic signal light 2 ... Outer lens 2a: Lens cut for diffusion 21, 24 ... Narrow angle diffusion lens cut 22 ... Wide angle diffuser lens cut 23 ... Prism part 2b ... section 3 ... Inner lens 31 ... Center 32 ... Middle part 33 ... Outer part 3a ... Lens cutting for focusing 4 ... Light source board 5 ... LED lamp

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI // F21W 111: 02 F21Q 1/00 N F21Y 101: 02 3/00 Z (58) Fields investigated (Int.Cl. ⁷ , DB name) G08G 1/095 B61L 5/18 F21S 2/00 F21S 8/10 G02B 3/08 F21W 111: 02 F21Y 101: 02

Claims (4)

(57) [Claims] 1. An outer lens having a diffusing lens cut for forming a light distribution, and a Fresnel lens-shaped converging lens cut for causing light to enter the outer lens as substantially parallel rays. An inner lens,
A plurality of LEs arranged with a predetermined area on the light source substrate
In an LED traffic signal lamp including a D lamp, the focus of the lens cut for converging the inner lens is on or near the center line of the inner lens, and the converging lens on the outer periphery of the inner lens. In the cutting, the focal length is the distance to the position where the extension of the line connecting the outer periphery of the inner lens and the LED lamp provided on the outer end of the light source substrate intersects the center line, and the center of the inner lens In the converging lens cut, the focal length is the distance from the inner lens to the LED lamp provided at the center of the light source substrate,
In the converging lens cut at the intermediate position between the outer circumference and the center, the focal length is changed stepwise or gradually as an intermediate value between the focal lengths set at the outer circumference and the center. Signal lights. 2. An LED traffic signal lamp in which the outer lens surface is divided into a substantially cross-shaped pattern, and a diffusion lens cut for forming a light distribution characteristic is formed in each of the divisions. For the cut, a narrow angle diffusion lens cut mainly responsible for light distribution in the front direction of the lamp as a relatively narrow diffusion angle, and a wide angle diffusion lens mainly responsible for general light distribution as a diffusion angle wider than the narrow angle diffusion lens cut are cut. At least two types of cuts are prepared, and different types of diffuser lens cuts are arranged so as to be alternately repeated in the section. 3. The LED according to claim 2, wherein the narrow angle diffusing lens cut is a concave lens system.
Traffic signal lights. 4. A diffusing lens cap for forming a light distribution.
With an outer lens and the outer lens
Fresnel lens shape for making light incident as row light
An inner lens with a converged lens cut,
A plurality of LEs arranged with a predetermined area on the light source substrate
An LED traffic signal lamp including a D lamp, comprising:
The focus of the lens cut for convergence of the inner lens is
Exists on or near the centerline of the Naren lens
And the convergence lens on the outer circumference of the inner lens.
In the light cut, the outer circumference of this inner lens and the light source
The extension of the line that connects to the LED lamp provided on the outer edge of the substrate
The focal length is the distance to the position where the length intersects the center line.
The lens cut for converging the center of the inner lens
Then, from this inner lens to the center on the light source board
The focal length is the distance to the provided LED lamp,
With a lens cut for convergence at an intermediate position between the outer circumference and the center,
A step is set as an intermediate value between the focal lengths set at the circumference and center.
The focal length is changed stepwise or gradually,
Less than 20 LED lamps are arranged on the light source substrate
And is separated from the inner lens by a space.
The outer lens has a substantially go-shaped outer lens surface.
Divide into a grid and form a light distribution in each of the divisions.
A diffusion lens cut for
A relatively narrow divergence angle is mainly used for lens cutting
Narrow angle diffusion lens cut that is in charge of light distribution in the front direction,
Mainly as a wider diffusion angle than the narrow angle diffusion lens cut
Less with wide angle diffuser lens cut, which is responsible for overall light distribution
Both types are prepared, and different types of
It is arranged so that the scattering lens cuts are repeated alternately.
LED traffic signal lamp, characterized in that there.