JPH0581904A - Road lighting system - Google Patents

Abstract

PURPOSE:To provide a road lighting system in which the whole span of a forward road is brightened so as to be visually reaognized even if the road surface is wetted by rain. CONSTITUTION:A lamp 35 and a reflecting plate 36 are alternately arranged along a road. When a measuring device of road surface state judges that the road surface is wetted, a lamp 38 is lighted in addition to the lamp 35. Thus, the reflecting plate 36 provided beyond it is lighted, and its image is brightly reflected on the road surface. Since this is arranged alternately with the lamp 35 directly lighting the road surface to compensate the space between the lamps 35, a dark part of stripe pattern is eliminated or extremely minimized. Therefore, the whole road surface is brightened, and visual recagnizability of obstruction is further improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a night lighting system for automobile roads, particularly when the road surface is wet due to rain or the like.

[0002]

2. Description of the Related Art As a conventional road lighting device, for example, there is one shown in FIG. Road lighting is brighter than the lighting range of automobile lighting lamps on the road surface and its surroundings, and a long line-of-sight distance can be obtained, making it easy to check the position and size of obstacles on the road. It is effective in reducing accidents at night. This is because the lighting fixtures 3 are arranged so that the road surface 1 has a uniform brightness by continuous illumination along the road. As a result, it is considered that the obstacles are easily visible and the road alignment in front is easy to understand, which gives the driver a sense of security and enables the driver to drive with plenty of time, thereby reducing accidents.

[0003]

However, in such a conventional road illuminating device, the lighting fixture 3, particularly the lamp 5 thereof, has a considerable amount W from the side edge 2 to the center of the road.
However, it was fixed with the overhanging arrangement, and had only a uniform lighting pattern regardless of the weather. In the case of a dry road surface, if the lamp 5 is located at the center of the road, the light will be diffused on the road surface 1 and the entire road ahead will appear to have uniform brightness, which is ideal, but if the road surface 1 gets wet due to rain etc. , A state similar to that of a mirror surface and the amount of specularly reflected light increases, so
As in 1, only the road surface directly under the lamp becomes linearly bright,
Obstacles in most dark places except on the bright line 7 become difficult to see.

Particularly, on the road on which the vehicle is traveling, the lamps 5 of the luminaires which are continuous in front are arranged on a vertical line extending almost from above the driver's head, and only this one line is bright and the shoulder side is continuous. It becomes dark and the shoulders are almost invisible. For this reason, the current situation is that the overhang is set halfway compromised, but the problem that the shoulder portion is hard to see when the road surface is wet has hardly been solved.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a road illuminating device which can visually recognize the entire road ahead even when the road surface is wet due to rain or the like, focusing on the above conventional problems.

[0006]

For this reason, the first and second aspects of the present invention include a lamp which is turned on by directing the irradiation direction to the road surface, and the position of the turned-on lamp is the amount of overhang from the side edge of the road. Is provided along the road with a lighting device that can be switched to different positions, and a road surface condition measuring device that measures whether or not the road surface is wet, and a signal indicating that the road surface is wet from the road surface condition measuring device. Upon reception, a lamp control device for issuing a switching signal for setting the turned-on lamp position to a position with a small overhang amount is provided to expand the clear vision range of the road shoulder portion when the road surface is wet.

According to a third aspect of the present invention, a lighting fixture having a first lamp that is turned on with its irradiation direction directed to the road surface and reflectors are provided alternately along the road. Is further provided with a second lamp directed to the adjacent reflection plate, a road surface condition measuring device for measuring whether or not the road surface is wet, and a signal indicating that the road surface is wet from the road surface condition measuring device. Upon receipt of the light, a lamp light distribution control device for issuing a light distribution command for turning on the second lamp of the lighting equipment is provided so as to expand the clear vision range of the road shoulder portion when the road surface is wet.

[0008]

According to the invention of claims 1 and 2, when the road surface is wet, the lighting lamps are arranged close to the side edge of the road, and due to the reflection of those lamps, a striped pattern is formed, and bright lines are increased. The visibility of the part is improved. In addition, in this case, when a semi-transparent plate is provided in front of the lamp, the light amount is reduced, so that the contrast of the striped pattern becomes gentle and the dark portion becomes easy to see.

According to the third aspect of the present invention, when the road surface is wet, the reflector provided between the first lamps for irradiating the road surface is also brightly illuminated by the second lamp so that the distance between the first lamps is increased. Is also filled in, and it is also reflected in a wet road surface and becomes a light line, improving the visibility of the road shoulder part.

[0010]

1 to 3 show a first embodiment of the present invention, which comprises a road surface condition measuring device 20, a lamp control device 24, and a lamp moving device 26 provided in a lighting fixture 13. As shown in FIG. 2, the road surface condition measuring device 20 includes a luminance meter 21 for measuring the luminance of the road surface 1 illuminated by the lighting fixture 13.
And a vehicle detector 22 for checking whether or not an automobile exists on the measurement point, and the brightness values of a dry road surface and a wet road surface are measured in advance to set a reference value,
From this reference value and the brightness measured when there is no vehicle, it is determined whether the current road surface is wet. In this way, the road surface condition measuring device 20 successively measures the brightness of the road surface and determines whether or not the road surface is wet.

As shown in FIG. 3, the ramp moving device 26 is constructed so that the ramp 5 can be moved along the horizontal bar 18 extending from the upper end of the pole 17 in the width direction of the road as indicated by the arrow. When a determination signal that the road surface is wet is input from the road surface state measuring device 20 to the lamp control device 24,
The lamp control device 24 sends a position switching signal in the side edge direction. Receiving this signal, the lamp moving device 26 moves the lamp 5 to a position where the overhang amount from the road side edge 2 is close to zero. As a result, as shown in FIG. 4, the bright lines 30 of the lamps 5 of the respective lighting fixtures are lined up along the road shoulder, which is in the clear range and makes it easy to visually recognize obstacles on the road shoulder.

When the road surface condition measuring device 20 determines that the road surface is dry, the overhang amount is increased and
Move so that the ramp 5 is near the center of the lane.

As described above, according to this embodiment, the lamp 5 is moved to change the amount of overhang according to the road surface condition. Therefore, when the road surface is dry, the central portion of the road is illuminated. As a result, it is possible to increase the lighting rate and increase the brightness of the road surface, and on the other hand, it is possible to avoid the fact that the shoulder side is completely dark even when the road surface is wet. Further, since the illumination rate becomes high as described above at the time of drying, it is possible to eliminate unnecessary light, reduce the light amount, and contribute to energy saving.

The road surface may be wet even if it is not raining, and vice versa. However, since the road surface condition is judged by the brightness of the road surface, it is judged whether or not it is raining with a raindrop sensor or the like. There is an advantage that the road surface condition can be grasped more accurately than the case. Furthermore, the road surface condition measuring device 20
If each of the lighting fixtures 13 is installed, fine control can be performed even on a road where some parts are dry but some parts are wet.

In the above embodiment, instead of the ramp moving device 26, as shown in FIG. 5, the ramps are provided at two positions on the horizontal bar 18, a position corresponding to the vicinity of the center of the road and a position near the zero overhang amount. The same effect can be obtained by installing 5 and 15 and switching the lighting of these lamps by a signal from the lamp control device 24.

FIG. 6 shows a second embodiment. Although the bright area can be expanded to the road shoulder portion by the first embodiment, when the road surface is wet, specular reflection occurs and the bright portion has higher brightness than when it is dry, and therefore, the bright portion and the dark portion. The contrast with is strong. In the second embodiment, this contrast is weakened to further improve the effect of the previous embodiment. That is, when the road surface is dry, the overhang amount is increased and the road surface is illuminated by the point light source as in the previous embodiment. On the other hand, when the road surface is wet, the lamp 5'located at a position where the amount of overhang is small
In addition to illuminating the road surface, the lighting fixture 13 'is provided with a semi-transparent plate 28 having a predetermined area in front of the lamp at this position.

According to this structure, the amount of light is reduced by the amount of light passing through the semi-transparent plate 28, the brightness is moderated, and at the same time, the point light source of the lamp becomes a surface emitting light source having a predetermined area. Therefore, the contrast of the striped pattern between the bright portion and the dark portion is weakened, the width of the bright portion is widened by the surface emission, and the visibility of the road shoulder portion is further improved.

FIG. 7 shows a third embodiment in which the visibility of the road shoulder portion is further improved when the road surface is wet. Lighting fixtures 33 having lamps 35 on the upper ends of the poles 17 are installed at predetermined intervals along the road, and similar poles 37 are installed between the respective lighting fixtures 33, and reflectors are installed at the upper end of the lighting fixtures 33 at positions corresponding to the lamps. 36 are provided. Therefore, the lamps 35 and the reflectors 36 are arranged alternately.

As shown in FIG. 8, the luminaire 33 is provided with a lamp 38 directed to the road surface and a lamp 38 directed to a reflector 36 on the road front side of the luminaire.

FIG. 9 shows a control device, in which the same road surface condition measuring device 20 as that used in the previous embodiment is used, and a lamp light distribution control device 32 for issuing a light distribution command when a judgment signal indicating that the road surface is wet is received. Has been. When the road surface is dry, the lamp 35 is turned on to illuminate the road surface. Light diffuses on the road surface and the entire road ahead looks bright. When the road surface condition measuring device 20 outputs a determination signal that the road surface is wet, the lamp light distribution control device 32 turns on the lamp 38 in addition to the lamp 35 of the lighting fixture 33. As a result, the reflector 36 installed in front of it is illuminated, and the image is brightly reflected on the road surface.

According to this embodiment, the light from the lamp 38 of the luminaire 33 is applied to the reflecting plate 36 to illuminate a relatively large area brightly, and this directly illuminates the road surface.
Since the areas between the lamps 35 are complemented by alternately arranging with, the dark portion of the striped pattern disappears or becomes extremely small even when the road surface is wet. Therefore, the entire road surface becomes brighter,
The visibility of obstacles is further improved.

[0022]

As described above, according to the first and second aspects of the present invention, the amount of overhang of the lamp is changed according to the road surface condition. Therefore, when the road surface is dry,
By illuminating from near the center of the road as much as possible to increase the lighting rate, it is possible to increase the brightness of the road surface, while on the other hand, when the road surface is wet, the amount of overhang is reduced so that the shoulder side is all dark. The visibility of the side edge of the road is improved.

In particular, in the embodiment in which a semi-transparent plate having a predetermined area is provided on the front side of the lamp with a small amount of overhang, the contrast between the bright portion and the dark portion becomes gentle and the width of the bright portion is reduced by surface emission. There is an advantage that the visibility of the road shoulder portion is further increased.

According to the third aspect of the present invention, the reflector is provided between the lamps for illuminating the road surface, and when the road surface is wet, the reflector is illuminated to complement the space between the lamps. Has the effect of being able to.

[Brief description of drawings]

FIG. 1 is a diagram showing a control device used in an embodiment of the present invention.

FIG. 2 is a diagram showing a road surface state measuring device.

FIG. 3 is a diagram showing a lighting fixture in an example.

FIG. 4 is a diagram showing a visual recognition state of a road surface according to an embodiment.

FIG. 5 is a diagram showing another example of a lighting fixture.

FIG. 6 is a diagram showing a second embodiment.

FIG. 7 is a diagram showing a third embodiment.

FIG. 8 is a diagram for explaining the operation of the third embodiment.

FIG. 9 is a diagram showing a control device used in a third embodiment.

FIG. 10 is a diagram showing a conventional example.

FIG. 11 is a view showing a road surface visual recognition state according to a conventional example.

[Explanation of symbols]

 1 Road Surface 2 Road Side Edge 3 Lighting Fixture 5 Lamp 7 Bright Light Line 13, 33 Lighting Fixture 17, 37 Pole 18 Horizontal Bar 20 Road Surface Condition Measuring Device 21 Luminance Meter 22 Vehicle Detector 24 Lamp Control Device 26 Lamp Moving Device 28 Translucent Plate 30 Bright line 32 Lamp light distribution control device 35 Lamp 36 Reflector 38 Lamp W Overhang

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G09F 13/00 W 7319-5G (72) Inventor Seinori Saito 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Within Nissan Motor Co., Ltd.

Claims (3)

[Claims] 1. A lighting device provided with a lamp that is turned on by directing an irradiation direction to a road surface, and the position of the turned-on lamp can be switched to a position having a different overhang amount from a side edge of the road. A road surface condition measuring device which is provided along with the road surface condition measuring device for measuring whether or not the road surface is wet, and when a signal indicating that the road surface is wet is received from the road surface condition measuring device, the lamp position to be lit is adjusted to indicate an overhang amount. With a lamp control device that emits a switching signal to a small position,
A road lighting device characterized in that when the road surface is wet, the visible range of the road shoulder portion is expanded. 2. The road lighting device according to claim 1, wherein the lighting device includes a semi-transparent plate in front of the lamp at a position where the overhang amount is small. 3. A lighting fixture having a first lamp that is turned on with its irradiation direction directed to the road surface and reflectors are provided alternately along the road, and the lighting fixture is further adjacent to the lighting fixture. A road surface condition measuring device provided with a second lamp directed to the reflector and measuring whether or not the road surface is wet, and the lighting fixture when a signal indicating that the road surface is wet is received from the road surface condition measuring device. The road illumination device having a lamp light distribution control device for issuing a light distribution command for lighting the second lamp of (1), and expanding the visible range of the road shoulder portion when the road surface is wet.