JPS5928002B2 - road lighting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a road lighting device that illuminates roads, etc. by housing a high-efficiency light source such as a high-pressure mercury lamp or a high-pressure sodium lamp inside a reflecting mirror.

Road lighting equipment in Japan generally has a configuration in which a diffused light source 3 such as a fluorescent high-pressure mercury lamp is housed inside a reflector 2 covered with a prism globe 1, as shown in FIG.

The advantage of using a diffused light source is that when controlling the light distribution using a reflector and a prism globe, there is little variation in light distribution performance even if the design and manufacturing accuracy is poor, and it can be easily commercialized. When irradiating a road, there is relatively little unevenness in irradiation.

Figure 2 shows a comparison of light distribution between a conventional lamp equipped with a fluorescent high-pressure mercury lamp [F] and a conventional lamp equipped with an ordinary high-pressure mercury lamp with a transparent glass outer bulb.

On the other hand, the disadvantage is that since the diameter of the lamp is larger than the width of the reflector, most of the light reflected by the reflector is absorbed by the lamp itself and is not used effectively.

For example, if we look at the light emitted from the side of the lamp, as shown in Figure 3, the light reflected from the 0 part of the reflector exits in the direction A, but most of the light reflected from the 0 part is from the lamp. It is absorbed by the outer sphere.

Also, if we look at the light emitted above the lamp, the fourth
As shown in the figure, almost all of it is absorbed by the lamp's outer sphere.

As a result, only about 10 to 15 times of reflected light is used as a whole, resulting in a lamp with poor illumination efficiency.

As a means to increase the utilization of light emitted from the side of the lamp,
As shown in FIG. 5, there is a method of increasing the size of the reflecting mirror relative to the lamp, or as shown in FIG. 6, the lamp is inserted deeper into the glove side and the direct light is controlled by a prism rather than the reflected light.

However, the former method increases costs, and the latter method has the disadvantage that the lamp is not shielded with a reflecting mirror, resulting in light distribution with large glare at high angles.

In addition, as a means to increase the utilization rate of the light emitted above the lamp, there is a method of protruding the upper part of the reflector toward the light source in a V-shape as shown in Fig. It had no effect and could only utilize the reflected light (■).

Moreover, regarding the reflected light ■, the front and rear directions of the reflecting mirror, that is,
Since there is no control in the width direction of the road, the reflected light concentrates directly below the lamp, resulting in poor symmetry (3) Furthermore, when a high-pressure sodium lamp is used as a light source, the reflected light is concentrated directly below the lamp, resulting in poor uniformity. Another drawback was that the returned reflected light raised the temperature of the arc tube, resulting in an increase in lamp voltage and shortened lamp life.

As described above, the biggest drawback of conventional road lighting equipment is that the light utilization rate is extremely poor, and the maximum luminous intensity value M when illuminating a road is, as shown in Fig. 8, the lamp luminous flux 110
At most, the intensity was about 180 to 330 cd per 100 tons, which was only 2 to 3 times the luminous intensity of direct light from the lamp.

As described below, this cannot be said to be sufficient as a road lighting device.

In other words, road lighting fixtures are generally installed at intervals S that are 3.5 times the light height H, as shown in Figure 9, for example, H = 8 m.
In this case, S=28m.

The 1/2S position is the farthest position from both lamps, and the angle θ is 60°15'.

Therefore, the direction in which the maximum luminous intensity of light distribution is obtained is usually 60°.
Designed front and back.

The illuminance is calculated by E=Icos3θ/H2, so if both points A and B are set to 10tX, the luminous intensity required by the lamp is 640 cd for point A and 640 cd for point B. However, since BA is irradiated from both lamps, it is 2623 cd per lamp.

In other words, the luminous intensity for point B is required to be about four times that of point A directly below.

In contrast, with conventional lamps, the luminous intensity in the 60° direction is approximately 1.5 times or less than the luminous intensity in the 0° direction, which is less than half of the required luminous intensity, as shown in the light distribution in Figure 8. is the current situation.

The illumination rate in this case is about 25 times, and the illuminance distribution is as shown on the P side of Figure 10.

As mentioned above, conventional lighting equipment using a diffused light source
Because the maximum luminous intensity value was low (and the illumination rate was poor), only about 25 to 35% of the total luminous flux of the lamp was used for illuminating the road surface.

One of the objects of the present invention is to provide a road illumination lamp with a high maximum luminous intensity value and a good illumination rate by effectively utilizing the luminous flux without making the lamp large or using a complicated prism globe. It is said that

Another object of the present invention is to provide a lamp having a structure in which a highly uniform opening distribution is obtained, and even when a high-pressure sodium lamp is used as a light source, the lamp does not deteriorate prematurely.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 11 is a plan view of a reflecting mirror of a road illumination lamp according to the present invention.

FIG. 12 is a cross-sectional view of the same reflecting mirror along the line xx', and FIG. 13 is a cross-sectional view of the same <z-z' portion.

This reflecting mirror has a portion U located substantially above the light source F and portions S1 and S2 located on the sides of the light source F.

Portions S1 and S2 located on the sides of the light source F are configured with multifocal reflective surfaces that reflect the light emitted from the sides of the light source F toward specific portions in the traveling direction and width direction of the road.

This multifocal reflective surface has a reflective surface AXB as shown in FIG.

It is constructed by connecting a plurality of unit reflecting surfaces which are divided into sections C and D, and each section is further divided into sections 1, 2, 3 and 4 as shown in FIG.

Each of these unit reflective surfaces A-1 to D-4 corresponds to a small area a-■ to d-■ formed by dividing the road in the traveling direction and width direction into a plurality of parts, as shown in Fig. 14. It has a curved surface and area that provides constant illuminance to each small area.

For example, the unit reflective surface B-1 has an optical axis that reflects the light emitted from the light source F at point O and focuses it on point Y.
The light reflected by this unit reflective surface is
This will cover most of the area and provide a constant level of illumination to that area.

The same applies to other unit reflective surfaces.

The luminous intensity or luminous flux required for each surface may be appropriately distributed depending on the length and light distribution of the lamp, and the solid angle and area of the reflecting surface.

For this purpose, it is desirable that the light source housed in the reflecting mirror be a linear light source, and a high-pressure sodium lamp or the like with a transparent glass outer bulb is suitable.

The reflected light is not blocked or absorbed by the light source due to stiffness, and the luminous flux can be used effectively.

Next, in the present invention, the portion of the reflecting mirror located above the light source F is configured with a multi-stage anti-body surface that reflects the light emitted above the light source F downward and forward on both sides of the mirror while avoiding the 90° angle. There is.

As shown in Fig. 12, this multi-stage reflecting surface has an almost V-shape in the transverse (width direction) cross section of the reflecting mirror and protrudes toward the light source, and as shown in Fig. Longitudinal direction)
The cross section is serrated.

The V-shaped portion distributes the reflected light to both sides of the light source so that the reflected light is not blocked by the light source, and the serrated step portion also distributes the reflected light to both sides of the light source. It is configured to irradiate portions a-■ to d-( of the road).

However, in the present invention, by placing each part of the multi-stage reflective surface ahead of the position of the multifocal reflective surface that should be separated to the side, the reflected light is further distributed over the width of the road. There is one that is configured to irradiate the front.

Therefore, in Fig. 14, the reflected light that would normally be irradiated on C-■ is on b-■ or b-■, and the six reflections f- that would be irradiated on b- −■ will be irradiated respectively.

With this configuration, the degree of uniformity of light distribution can be improved.

In FIG. 13, dotted lines indicate reflected light from the conventional lamp.

Furthermore, in the present invention, a small-area V-shaped protrusion V that can protrude toward the light source may be formed in a V-shaped cross-sectional portion of the multi-stage reflective surface.

Such a structure prevents reflected light from returning to the direction of the lamp arc tube, and is extremely effective in preventing an increase in lamp voltage when a high-pressure sodium lamp or the like is used.

Even by simply providing a V-shaped protrusion about the same length as the arc tube, the increase in lamp voltage can be suppressed to about 5V.

Finally, specific effects of the present invention will be explained based on examples.

As an embodiment of the present invention, it has a structure as shown in FIGS. 11 to 13, and has a length of 300 rrvn, a width of 250 mm,
A 150W high-pressure lamp with a 145mm height aluminum reflector equipped with a transparent glass outer bulb; The results were as follows compared to conventional lamps.

The conventional light fixture is 370mm long and 250rrvn wide.
400W inside an aluminum reflector with a height of 140mm
The firefly light is equipped with a high-pressure mercury lamp.

In this case, the illuminance distribution of the road illumination lamp according to the present invention was as shown on the ■ side of FIG.

Further, the vertical light distribution was as shown in Fig. 15.

As is clear from this figure, the maximum luminous intensity value of the lamp in the approximately 60° direction is ~500 cd per 1000 tm of lamp luminous flux.
It reached 600 cd, which was 2.5 to 3 times that in the 0° direction.

Furthermore, glare, which causes discomfort to car drivers and impairs the visibility of obstacles, has been compared to JIS standard values.
As shown below, it has become extremely rare.

Further, according to the present invention, as can be seen from the size comparison of the reflecting mirrors, it is clear that the luminous flux can be effectively utilized without increasing the size of the reflecting mirror and without using a complicated prism globe. .

Moreover, in the high-voltage lamp used in the embodiments of the present invention, the lamp voltage rise during lighting stays within 5V,
There was no adverse effect on lamp life.

As described above, according to the present invention, the performance of road illumination lamps can be greatly improved, and the present invention has great industrial value.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional road lighting device, Fig. 2 is a comparison diagram of light distribution using the same lamp, Figs. 3 and 4 are explanatory diagrams of the optical system of the same lamp, and Figs. 5 to 7 is an explanatory diagram of the improved optical system of the same lamp, Fig. 8 is a maximum luminous intensity diagram of the same lamp, Fig. 9 is an explanatory diagram of road lighting, Fig. 10 is a comparison diagram of light distribution between the lamp according to the present invention and a conventional lamp, and Fig. 11 13 are explanatory diagrams of the reflector of the lamp of the present invention, FIG. 14 is an explanatory diagram of road illumination by the same lamp, and FIG. 15 is a comparison diagram of vertical light distribution between the lamp of the present invention and a conventional lamp. In FIGS. 11 to 13, U...multistage reflective surface, Sl/S2...multifocal reflective surface, F...
···light source.

Claims (1)

[Scope of Claims] 1. In a road lighting device in which a linear light source is housed inside a reflecting mirror, the reflecting mirror has a portion that is located substantially in the middle of the light source and a portion that is located on the side of the light source. The part located above the light source is configured with a multi-stage reflective surface that reflects the light emitted above the light source downward and forward on both sides of the light source, avoiding the light source, and the part located on the side of the light source The multi-focal reflecting surface reflects light emitted to the side of the road toward a specific portion in the traveling direction and width direction of the road, and the multi-stage reflecting surface is configured with a multi-focal reflecting surface that is connected to the side of the road. A road illumination lamp characterized in that it is configured to irradiate reflected light further forward in the road width direction by positioning it ahead of the position of the focal reflection surface. 2. In the road lighting device according to claim 1, the multi-stage reflective surface portion of the reflecting mirror has a substantially V-shape in a cross section in the lateral direction (width direction) of the reflecting mirror, and projects toward the light source side. The cross section of the reflective mirror in the longitudinal direction (back and forth direction) is formed in a serrated shape, and the multifocal reflective surface part of the reflective mirror is
Formed by connecting a plurality of unit reflective surfaces having curved surfaces and areas that give a constant illuminance to each small area corresponding to the small area formed by dividing the road in the direction of travel and width. A road lighting fixture characterized by: 3. In the road lighting device according to claim 2, the section of the multi-stage reflective surface of the reflector having a substantially V-shaped cross section further includes a small-area V-shaped protrusion that can protrude toward the light source. Features of road lighting 1: Lighting equipment.