JP5032816B2 - Tunnel lighting method - Google Patents

Description

  The present invention relates to a tunnel illumination method for illuminating a tunnel by installing a lighting fixture only on a wall surface on one side with respect to the traveling direction of an automobile.

Conventionally, various tunnel illumination methods have been proposed in which a lighting fixture is installed only on a wall surface on one side with respect to the traveling direction of an automobile to illuminate the inside of the tunnel (see, for example, Patent Document 1).
JP 2003-234001 A

  By the way, in the above-described conventional method, an abrupt brightness change occurs between a region irradiated with direct light and a region not irradiated with direct light near the ceiling of the tunnel wall surface. Note that the boundary line of such a region where a sudden luminance change occurs is called a cut-off line.

  The main purpose of tunnel lighting is to make the road surface and the wall surface of the tunnel have the required brightness, and the driver's visibility is improved by brightening the background of obstacles and preceding cars on the road, and traveling in the tunnel Car safety can be ensured. It is also important to appropriately ensure not only the road surface and wall surface, but also the visual environment of the entire driver's field of view. For example, when the driver turns his / her gaze mainly in the direction of travel and perceives any change in the field of view, he / she takes actions necessary to maintain safe driving by moving his / her gaze in the direction in which the change occurred. Luminance change in space is also one of the changes perceived by the driver as described above. If there is a clear brightness change (cut-off line) in the driver's field of view, the driver's attention is given to the driver's attention. Since the vehicle is moved in that direction, there is a risk that the safety in traveling may be impaired.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a tunnel illumination method in which a change in luminance generated on a tunnel wall surface is reduced.

In order to achieve the above object, the present invention provides a lighting method for illuminating a tunnel by installing a lighting device only on a wall surface on one side with respect to the traveling direction of an automobile. Shaped fixture body, a lamp socket to which a single-tube straight tube discharge lamp is detachably mounted, a ballast for lighting the discharge lamp mounted in the lamp socket, and light emitted from the discharge lamp Is reflected toward the front opening of the fixture body, and the reflector has a maximum irradiation angle of about 60 degrees above the illumination light with respect to the optical axis of the illumination light. The irradiation light has a width of about 16 meters or more and a maximum ground height of about 8.5 meters or more, and the irradiation light is positioned at a height of about 6 meters or more in a tunnel having a substantially semicircular cross section perpendicular to the traveling direction. Vertically below the optical axis It characterized in that it placed inclined by a predetermined angle of less than 90 degrees with respect to air.

  According to the present invention, a conventional method in which a luminaire having an illumination angle upward of illumination light with respect to the optical axis of illumination light having a value larger than approximately 60 degrees (for example, approximately 75 degrees) is installed in a tunnel under the same conditions. Compared with, the area irradiated with direct light per unit angle near the center of the tunnel wall becomes wider, so the brightness change that occurs between the area where direct light is irradiated and the area where direct light is not irradiated Can be relaxed.

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

  As shown in FIG. 3, the lighting fixture used in the tunnel lighting method of the present embodiment includes a box-shaped fixture main body 1 having an open front surface, a lamp socket 3 to which a discharge lamp 2 is detachably mounted, and a lamp socket 3. A ballast 4 for lighting the discharge lamp 2 mounted on the light source, and a reflector 5 for reflecting the light emitted from the discharge lamp 2 toward the front opening of the instrument body 1. The instrument main body 1 is formed in a flat rectangular box made of metal, and a pair of hinges 10 and 10 are provided at both ends on one end side (lower side in FIG. 3A) along the longitudinal direction. A transparent cover 6 is attached to the hinges 10 and 10 so as to be freely opened and closed. The cover 6 is formed of a translucent material such as glass into a flat plate shape that matches the outer shape of the opening portion of the instrument body 1, and the pair of hinges attached to both end portions on one end side along the longitudinal direction. 10, 10 is attached to the instrument main body 1 so as to be rotatable between a closed position where the opening of the instrument main body 1 is closed and an open position where the opening is opened. In addition, the stoppers 11 and 11 are provided in the both ends of the other end side (upper side in Fig.3 (a)) along the longitudinal direction of the instrument main body 1, These stoppers 11 and 11 are made into a closed position. The cover 6 is fixed in the closed position by being locked to an end portion of a certain cover 6. Further, a plurality of mounting brackets 12 are provided on the bottom surface of the outer side of the instrument body 1 so as to protrude to the wall surface of the tunnel, and the instrument body 1 is tunneled by screwing these mounting brackets 12. It is fixed to the wall.

  The discharge lamp 2 used in the above-mentioned lighting fixture is a straight tube type single-cap-type high-intensity discharge lamp (HID lamp), and has a cylindrical outer tube with a cap (not shown) attached to one end side. Similarly, a cylindrical arc tube 2c is accommodated in 2b so that the direction of the tube axis coincides with the tube axis direction of the outer tube 2b. The lamp socket 3 has one end in the longitudinal direction in the appliance body 1 such that the mounting direction of the discharge lamp 2 (direction parallel to the tube axis of the discharge lamp 2) is parallel to the cover 6 (bottom surface of the appliance body 1) in the closed position. It is arranged on the side. That is, in use, the tube axis of the discharge lamp 2 mounted on the lamp socket 3 is substantially parallel to the road surface inside the tunnel and the vehicle traveling direction.

  The reflecting plate 5 is provided so as to block the end of the main reflecting plate 50 on the lamp socket 3 side, and a bowl-shaped main reflecting plate 50 disposed at a position facing the opening of the appliance body 1 with respect to the discharge lamp 2. The auxiliary reflector 51 and the side edges along the longitudinal direction of the main reflector 50 and the plane extending integrally from the edge of the auxiliary reflector 51 so as to be substantially parallel to the opening surface of the instrument body 1. It is composed of a generally U-shaped collar portion 52. The main reflector 50 has a first reflecting surface 50a having a substantially parabolic shape in cross section perpendicular to the tube axis of the discharge lamp 2, and a second reflection having a substantially parabolic shape in which the cross sectional shape is smaller than that of the first reflecting surface 50a. The surface 50b is connected to the first reflective surface 50a disposed on the side close to the bottom surface of the instrument body 1 and the second reflective surface 50b disposed on the side far from the bottom surface of the instrument body 1 with respect to the first reflective surface 50a. And a third reflecting surface 50c. The auxiliary reflector 51 is a flat plate having an outer shape that matches the cross-sectional shape of the main reflector 50, and has a circular insertion hole (not shown) through which the discharge lamp 2 is inserted. The reflection plate 5 configured as described above is mounted in the instrument main body 1 by a mounting bracket (not shown). As shown in FIG. 3, the lamp socket 3 is arranged slightly shifted to the lower side with respect to the center of the instrument body 1 in the short width direction (vertical direction in FIG. 3), and is connected to the first reflecting surface 50a. The distance between the second reflecting surface 50b and the discharge lamp 2 is shorter than the distance from the discharge lamp 2.

  The ballast 4 is housed in a shield and a metal case for heat dissipation, and the end opposite to the lamp socket 3 along the tube axis of the discharge lamp 2 in the appliance main body 1 (the right end in FIG. 3A). Is arranged. A terminal block 7 is attached to the bottom of the appliance body 1, and the ballast 4, the lamp socket 3, and an external power source are electrically connected via the terminal block 7.

  Next, as shown in FIG. 1A, a tunnel having a total width W of 16 meters or more and a maximum ground height (maximum height from the road surface) H0 of 8.5 meters or more is used. A tunnel illumination method for illuminating the interior will be described.

  When the ground height H1 of the wall surface on one side (left side in FIG. 1A) is approximately 6 meters or more with respect to the traveling direction of the automobile, the second reflective surface 50b is relative to the first reflective surface 50a. It is placed near the center of the tunnel and the optical axis L1 of the irradiation light is inclined by a predetermined angle (<90 degrees) with respect to the vertical downward direction. The optical axis L1 of the irradiation light coincides with the normal direction of the opening surface of the instrument body 1.

  Here, an angle (hereinafter, referred to as “upward irradiation angle”) θ1 formed by light irradiated upward with respect to the optical axis L1 and the optical axis L1 is determined mainly by the second reflecting surface 50b of the reflecting plate 5, In the present embodiment, the reflector 5 is configured so that the maximum value of the upper irradiation angle θ1 (maximum upper irradiation angle) is approximately 60 degrees. Then, as the range (hereinafter referred to as “irradiation range”) where light (direct light) is irradiated at a position close to the center of the tunnel wall surface per unit angle, the wider the area S1 and the direct light are irradiated. It is possible to mitigate a change in luminance that occurs between the region where the light is not irradiated.

  For example, as shown in FIG. 2A, in the conventional method using the lighting fixture A ′ in which the reflecting plate 5 is configured only by the first reflecting surface 50a, the maximum value of the upper irradiation angle θ2 under the same installation conditions ( The maximum upward irradiation angle) is approximately 75 degrees (see FIG. 2B). In FIG. 2B, x indicates the relationship between the upper irradiation angle θ2 and the luminous intensity value of the irradiation light (value normalized with the optical axis direction L1 being 1) in the luminaire A ′, and □ indicates the present embodiment. 3 shows the relationship between the upper irradiation angle θ2 and the luminous intensity value of the irradiation light (value normalized with the optical axis direction L1 being 1) in the lighting fixture A used in the tunnel illumination method.

  Thus, when the lighting fixture A and the lighting fixture A ′ are installed at the same position, the irradiation ranges S1 and S2 in which direct light is irradiated at a location near the center of the tunnel wall surface per unit angle φ are as follows. Is larger than the maximum upward irradiation angle θ2 (= 75 degrees) of the lighting fixture A ′, the irradiation range of the lighting fixture A with respect to the irradiation range S2 of the lighting fixture A ′. S1 becomes wider (see FIG. 1A). Then, the brightness at a location near the center of the tunnel wall surface is actually measured. As shown in FIG. 1B, the horizontal axis indicates the distance from the installation location of the luminaire, and the vertical axis indicates the brightness (brightness) of the tunnel wall surface. As a result of the examination, the luminance change curve i when using the lighting fixture A has a gentler slope (ratio of luminance change) than the luminance change curve B when using the lighting fixture A ′. . Specifically, the amount of change in luminance per unit angle φ in the region surrounded by the dotted line in FIG. 1B is 0.29 in the case of the luminaire A ′, whereas in the case of the luminaire A Decreased to about ３, becoming 0.10.

  As described above, the lighting fixture A in which the reflecting plate 5 is configured so that the maximum value (maximum upper irradiation angle) of the upper irradiation angle θ1 is approximately 60 degrees has a total width of approximately 16 meters or more and the maximum ground surface. According to the tunnel illumination method of the present embodiment installed at a position of approximately 6 meters or more above the ground in a tunnel having a height of approximately 8.5 meters or more, the luminance change (cut-off line) existing in the driver's field of view is reduced. This makes it difficult to call the driver's attention, thus improving driving safety.

(A), (b) is explanatory drawing explaining embodiment of the tunnel illumination method which concerns on this invention. (A) is sectional drawing which shows the lighting fixture used for the conventional method, (b) shows the relationship between the illumination angle used for the tunnel lighting method which concerns on this invention, and the upper irradiation angle of the lighting fixture used for a conventional method, and a luminous intensity. It is a graph. The lighting fixture used for the tunnel lighting method which concerns on this invention is shown, (a) is a front view, (b) is sectional drawing.

Explanation of symbols

θ1 Upper illumination angle of the luminaire in the tunnel illumination method according to the present invention θ2 Upper illumination angle of the luminaire in the conventional method φ Unit angle S1 Irradiation range in the present embodiment S2 Irradiation range in the conventional method

Claims (1)

It is a lighting method that illuminates the inside of a tunnel by installing a lighting fixture only on one wall surface with respect to the traveling direction of the automobile. The lighting fixture is a box-shaped fixture body with an open front, and a straight tube with a single base. A lamp socket in which the discharge lamp is detachably mounted, a ballast for lighting the discharge lamp mounted in the lamp socket, and a reflection that reflects the light emitted from the discharge lamp toward the front opening of the fixture body The reflector has a maximum irradiation angle of the illumination light above the optical axis of the irradiation light of approximately 60 degrees, and the lighting device has a total width of approximately 16 meters or more and a maximum ground clearance of approximately 60 degrees. The optical axis of the irradiation light is less than 90 degrees with respect to the vertical downward direction at a height of about 6 meters or more in a tunnel having a height of about 6 meters or more in a tunnel having a cross-sectional shape perpendicular to the traveling direction of about 8.5 meters or more Only at a certain angle Only in tunnel lighting wherein the installing.

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