JP2013201068A - Lighting device for tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve light distribution characteristics of a lighting device for tunnel using an LED with a simple configuration and simple structure, so as to obtain a light distribution pattern capable of lighting an installation surface in a tunnel.SOLUTION: A lighting device for tunnel is provided with a fixture container (14), a translucent cover (12) having a lens element portion (17) for covering a front portion, an inner space (18) formed of the both, and an LED light source unit (11). The translucent cover is composed of a bottom part (121) and a tube part (122), and a prism group (6) of a cross-sectional triangle shape is configured at an inner surface of the central region of the bottom part (121), and a convex prism (8) is formed on an outer side face. An inner reflection part (123) is provided in the vicinity of the tube part. The inner reflection part reflects irradiation light from the LED light source unit toward a ground contact surface installing the lighting device through the tube part. Thereby, even if a reflecting mirror is not positively installed, a light distribution pattern with brightness unevenness reduced can be obtained, and the lighting device for tunnel which illuminates the installation surface too is provided.

Description

  The present invention relates to a lighting device for illuminating a road surface in a tunnel, and more particularly to a cave illuminating lamp such as an underground waterway, an electric / phone wiring cave, and a subway.

  Conventionally, lighting devices for illuminating the inside of tunnels such as highways, ordinary roads, underground waterways, electric and telephone wiring caves, and subways have been installed. In recent years, tunnel illumination devices using not only fluorescent light sources but also LEDs (light emitting diodes) as light sources have been proposed. In Patent Document 1, a lighting plate provided with a transparent cover covering a resin plate on which a plurality of light emitting diodes are disposed and a reflecting plate provided on the transparent cover is provided on the inner wall of the tunnel. . However, it merely uses the light distribution characteristic irradiated from the LED unit in which a large number of LEDs are arranged in a matrix on a flat plate, and a large number of LEDs must be used.

  In order to solve the above problem, the applicant proposed Patent Document 2. Patent document 2 has an instrument container, a translucent cover provided with a lens element portion covering the front, and an internal space formed by both, and an LED light source unit is provided in the internal space. Is arranged with a plurality of LED elements interspersed in a non-dot matrix, the incident side lens cut constitutes a parallel prism section with a triangular section, and the exit side lens cut constitutes a convex prism with a triangular section. The prism group is a tunnel illumination device having a plane having substantially the same acute angle with respect to a reference plane. Thereby, a light distribution pattern with reduced brightness unevenness can be obtained without actively providing a reflecting mirror.

JP 2002-324408 A JP 2010-262818 A

  However, in the tunnel illuminating device described in Patent Document 2, since the light distribution pattern is set to irradiate light in the front direction of the translucent cover, the wall surface to which the tunnel illuminating device is attached is dark and the tunnel illuminating device is attached. There is a problem that the state of the wall cannot be confirmed.

  Accordingly, the present invention has been made in view of the above problems, and the object of the present invention is to illuminate the mounting surface of a tunnel illumination device using an LED light source and improve the light distribution characteristics. Is to provide.

In order to achieve the above object, a tunnel lighting device according to the present invention includes:
An instrument container, a translucent cover that covers the front of the instrument container, and an LED light source unit that is disposed in an internal space formed by the instrument container and the translucent cover,
The translucent cover is a bottomed cylindrical shape convex toward the front of the instrument direction consisting of a cylindrical part attached to the opening edge of the instrument container and extending forward of the instrument container, and a bottom of the translucent cover,
The LED light source unit has a plurality of LED elements mounted on the substrate surface facing the inner surface of the bottom of the translucent cover,
In front of the optical axis of the LED element at the bottom of the translucent cover, a lens element portion provided with an entrance side lens cut and an exit side lens cut via an air layer,
Among the plurality of LED elements mounted on the LED light source unit, the optical axis of the LED element close to the cylindrical portion of the transparent cover, and the bottom of the transparent cover positioned between the LED element and the cylindrical portion Is characterized in that an internal reflection part that reflects toward the tube part is formed.

Further, the inner surface reflecting portion includes an incident surface facing the LED element having a triangular cut section provided on the inner surface of the bottom portion of the translucent cover, and a reflecting surface located outside the bottom portion of the translucent cover. The light incident on the incident surface and reflected on the reflecting surface is reflected obliquely toward the rear side of the instrument container through the tubular portion.
Furthermore, the incident side lens cut constitutes a prism group having a triangular cross section parallel to the incident side lens cut located in front of the other LED elements, and the output side lens cut is the prism of the corresponding incident side lens cut. The concave / convex prism having a continuous curved surface is formed in a range corresponding to the group, and the lens element portion is formed integrally with a light-transmitting resin on the incident side lens cut and the output side lens cut, and the incident side lens cut The prism group having a triangular cross section is separated from the LED element with respect to a plane having substantially the same acute angle with respect to a reference plane between the entrance side lens cut and the exit side lens cut, and a plane orthogonal to the reference plane. Characterized by having a plane with an acute angle that increases with

  The tunnel illumination device of the present invention has an advantage that a light distribution pattern suitable for a tunnel illumination device having a simple structure and improved light distribution characteristics of the tunnel illumination device using LEDs can be obtained.

  According to the invention described in claim 2, it is possible to irradiate the mounting surface of the inner wall of the tunnel to which the lighting device is mounted with a simple structure using light having low luminance among the light emitted from the LED. There are advantages.

  According to the third aspect of the present invention, there is an advantage that a light illumination loss due to the incident side lens cut can be reduced and a tunnel illumination device can be obtained in which the utilization efficiency of light from the LED is increased.

FIG. 1 is a side view showing an example of a tunnel illumination device of the present embodiment. 2 is a vertical cross-sectional view of the lighting device of FIG. 1 installed on the tunnel ceiling. 3 is an enlarged cross-sectional view of a portion B in FIG. 4 is a cross-sectional view schematically showing an LED element and a lens element portion of the tunnel illumination device of FIG. FIG. 5 is an explanatory diagram showing the light distribution characteristics of the passage when the tunnel lighting device of FIG. 3 is installed in the tunnel. FIG. 6 is an explanatory diagram showing light distribution characteristics in a state where the tunnel illumination device of FIG. 3 is installed in the tunnel. FIG. 7 shows the setting range of the prism groups 6 and 7 superimposed on the LED element 1 of the LED light source unit 11. FIG. 8 is a schematic cross-sectional view for explaining the design procedure of the incident side lens cut. FIG. 9 is a schematic cross-sectional view for explaining a design procedure of the exit side lens cut.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS A tunnel illumination device provided in a wiring cave for an electric / phone or the like according to an embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a side view showing an example of a tunnel lighting device of the present embodiment, FIG. 2 is a vertical plan sectional view of the lighting device of FIG. 1 installed on the tunnel ceiling, and FIG. 3 is an enlarged view of part B of FIG. FIG.
The tunnel illumination device 10 (hereinafter simply referred to as illumination device) includes an instrument container 14 whose front in the irradiation direction is open, an LED light source unit 11 disposed in the instrument container 14, and a front opening of the instrument container 14. The lens element part 17 is provided in the position which the LED light source unit 11 of the translucent cover 12 opposes. A lighting control device 19 is provided on the inner surface of the instrument container 14 on the back side of the LED light source unit 11. The tunnel may be installed in a place with high humidity or high temperature, or it may be submerged. Therefore, it is preferable that the light used is excellent in strength and waterproof so that it can withstand such light. It is preferable that the unit 11 and the lighting control device 19 be an immersion-proof illumination lamp that is housed in a waterproof case.

  When the LED light source unit 11 is turned on, the light emitted from the unit 11 enters the lens element unit 17 and is refracted by the lens element unit 17 to form a substantially elliptical light distribution pattern 86 as shown in FIG. . Here, the substantially elliptical light distribution pattern refers to a light distribution pattern in which the length direction of the tunnel along the passage that is an object to be irradiated in the tunnel is long. By adopting a substantially elliptical light distribution pattern, irradiation to unnecessary portions other than the passage is reduced as compared with a circular light distribution pattern, and the use efficiency of light emission is improved. 4 is a cross-sectional view schematically showing an LED element and a lens element portion of the illumination device of FIG. 3, and FIG. 5 is an explanation showing light distribution characteristics of the passage when installed in the tunnel of the illumination device of FIG. FIG. 6 and FIG. 6 are explanatory diagrams showing light distribution characteristics in a state where the lighting device of FIG. 3 is installed in the tunnel. FIG. 7 shows the setting range of the prism groups 6 and 7 superimposed on the LED element 1 of the LED light source unit 11.

  The instrument container 14 is made of metal, has a box shape or a plate shape whose front in the irradiation direction is open, and forms an internal space 18 with a translucent cover attached to the container. The back surface side of the instrument container 14 can be attached to a fixture 81 attached to the wall surface 31 of the tunnel by a known means such as a screw (not shown). In the example of FIG. 1, the instrument container 14 has a box shape, and a seal groove 14a having a U-shaped cross section is provided around it.

  The translucent cover 12 is made of a transparent resin such as acrylic or polycarbonate, and its peripheral edge is hermetically coupled to the instrument container 14. The translucent cover 12 is formed into a bottomed cylindrical shape having a cup shape in a state in which the lighting device 10 is attached to the tunnel ceiling, and a seal leg 12a is provided on a peripheral edge serving as an opening side end. After supplying an adhesive such as hot melt into the seal groove 14a, the seal leg 12a is press-fitted and fixed. Instead of using an adhesive, the two may be fitted through a rubber packing or the like, and the instrument container 14 and the translucent cover 12 may be sandwiched with a metal clip or the like to be hermetically coupled. The seal leg 12 a is integrally formed on the distal end side of the cylindrical portion 122, and is not provided on the translucent cover bottom portion 121.

  The LED light source unit 11 is disposed in the internal space 18. FIG. 5 is a plan view schematically showing the LED light source unit 11. FIG. 4 corresponds to a cross section taken along the line CC in FIG. The LED light source unit 11 includes an LED mounting substrate 2 made of a glass epoxy substrate, a ceramic substrate, a metal substrate, or the like on which a power supply wiring pattern is formed, and a plurality of LED elements 1 electrically and mechanically connected on the substrate. Become. The LED mounting substrate 2 preferably has thermal conductivity and high surface reflectance. This is because the heat dissipation of the LED light source unit 11 can be enhanced, and light outside the design due to internal reflection from the translucent cover 12 can also be used effectively. The LED element 1 is, for example, of a surface-mount type, and is installed such that its optical axis A faces the irradiation direction of the illumination device 10, that is, the lower side of the page in FIGS.

  The LED element 1 is preferably a rectangular surface-mount type exhibiting a Lambertian characteristic with a full width at half maximum of 90 ° to 170 °, and in particular, a device that spreads around the LED chip on the emission side. This is because if the full width at half maximum is less than 90 °, the amount of light flux traveling in an oblique direction from the LED element 1 is small, so that the refraction of the lens element portion 17 described later must be increased, making it difficult to form the lens element portion. Further, if the full width at half maximum is greater than 170 °, the luminance immediately below the LED element 1, that is, the luminance on the optical axis becomes relatively low. Preferably, when the one having a full width at half maximum of 100 ° to 140 ° is used, the inner surface of the tunnel to which the illumination device 10 is attached can be illuminated by the inner surface reflecting portion 123 described later. In addition, each LED element 1 is arranged in a non-dot matrix. The number of LED elements used can be reduced by providing them scattered.

  Next, the lens element part 17 and the internal reflection part 123 for making the light irradiated from the LED light source unit 11 a predetermined light distribution will be described.

  First, the inner reflection part 123 will be described. The internal reflection part 123 is provided on the translucent cover bottom 121 near the cylindrical part 122. Specifically, as shown in FIG. 3, the translucent cover is integrated with the translucent cover bottom 121 located between the cylindrical portion 122 and the optical axis Aa of the LED element 11 a closest to the cylindrical portion 122. To form.

  As shown in FIG. 3, the inner surface reflection portion 123 includes a plurality of triangular prism cuts 123 a provided on the inner surface of the translucent cover bottom portion 121 and a reflection surface 123 b outside the translucent cover bottom portion 121. . The prism cut 123a is incident so that a part of the light (light rays L2 and L3) emitted in an oblique direction away from the optical axis Aa emitted from the LED element 11a easily enters the inside of the translucent cover bottom 121. It is provided to make the angle smaller than the critical angle. That is, the incident surface 123a1 on the LED element 11a side of the prism cut 123a rises toward the LED element 11a. The other side 123b is made to be a shadow of the adjacent prism cut 123. This is because the direct light from the LED element 11a is not reflected by the surface 123b.

  The reflection surface 123b outside the translucent cover bottom portion of the inner surface reflection portion 123 is such that light rays L2 and L3 incident on the inside of the translucent cover bottom portion 121 from the prism-cut LED element side incident surface 123a1 are outside the translucent cover bottom portion. This is a reflection surface in which a large amount of reflected light component is generated at the interface between the reflection surface 123b and air. The light reflected at the interface travels toward the tube portion 122, more specifically, to be reflected obliquely upward so as to pass through the tube portion 122 toward the rear side of the instrument container. In the present embodiment, the outer diffusion surface 122 a is provided with irregularities on the outer surface of the cylindrical portion 122. By setting it as a diffusion surface, the light which goes to the air from the cylinder part outer side diffusion surface 122a diffuses and advances. Thereby, the surface which attached the illuminating device in the tunnel located in the cylinder part 122 and its upper part can be illuminated. The cylindrical portion 122 may be a through surface without providing the outer diffusion surface 122a.

  The main alignment formation region 124 will be described. The main orientation formation region 124 is a region facing the LED light source unit 11 and is provided at a position closer to the center of the translucent cover bottom 121 than the inner surface reflection portion 123. In the present embodiment, the lens element portion 17 formed integrally with the translucent cover 12 serves as the main orientation forming region 124.

  In the lens element portion 17, the incident side lens cut 5 on the surface facing the LED light source unit 11 and the emission side lens cut 7 provided on the opposite surface are integrally formed of the same material. Thereby, attenuation of the light before the light incident from the incident side lens cut 5 exits from the output side lens cut 7 can be suppressed. Further, the lens light source unit 11 can be viewed directly by combining the lens element portion 17 with a lens cut having different properties, that is, an incident side lens cut 5 having many steps and a curved exit side lens cut 7. It can be made difficult to observe, and the glare of the LED element 1 can be suppressed.

  A large number of incident side lens cuts 5 are formed on the surface of the lens element portion 17 on the inner space 18 side, and an air layer 15 exists between the light source unit 11 and the LED light source unit 11. In addition, an incident side prism group 6 having a triangular cross section is formed. Each of the prisms 6L1, 6L2, 6L3, 6R1, 6R2, and 6R3 is a triangular prism having a triangular cross section, and the length direction L of the passage 82 that is the irradiated object in the tunnel 80, that is, the tunnel length direction. Are arranged in parallel. The symbol L in FIG. 4 corresponds to the length direction L of the passage in FIG. Further, the triangular prisms 6L1, 6L2 and 6L3 on the left side of the optical axis A and the triangular prisms 6R1, 6R2 and 6R3 on the right side of the optical axis A are mirror surfaces with respect to a plane passing through the optical axis A and orthogonal to the length direction L. It is made into a shape. By using the mirror surface as an object, the uniformity of the light distribution pattern in the passage length direction can be easily increased.

  A large number of exit side lens cuts 7 are formed on the surface of the lens element portion 17 on the opposite side to the internal space 18 to constitute the exit side prism group 8. Each of the prisms 7L1 and 7R1 is a convex prism. Further, the point intersecting with the optical axis A becomes the boundary between the prism 7L1 and the prism 7R1, and is a recess 7c. As a result, the exit-side prism group 8 is formed as an uneven surface having a continuous curved surface. Furthermore, the area of the exit side prism group 8 is larger than that of the incident side prism group 6 corresponding thereto. By increasing the area of the exit-side prism group 8, the light incident on the entrance-side prism group can be extracted more efficiently to the outside.

  The area where the incident side prism group 6 and the emission side prism group 8 are provided is on the optical axis of each LED element 1 and a predetermined angular range around this, specifically, a range corresponding to at least the full width at half maximum of the LED element 1. Provide in. FIG. 7 shows the setting range of the prism groups 6 and 7 superimposed on the LED element 1 of the LED light source unit 11. In FIG. 7, reference numeral 6 </ b> E denotes a ridge line of the incident side lens cut 5 having a triangular prism shape in each of the incident side prism groups 6, and is orthogonal to the length direction L of the passage 82.

  The exit side prism group 8 has the same area as the area where the entrance side prism group 6 is provided or a larger area. This is because unevenness in the brightness of the light distribution pattern can be reduced by providing it in a larger area than the incident side prism group.

Details of the entrance-side lens cut 5 will be described along the design procedure with reference to FIGS. 8 and 9.
First, a distance D between the LED element 1 and the outermost surface of the LED light emitting unit 1H and an optical axis A passing through the center of the LED element 1 are set. The number of cuts and the pitch are set in consideration of the light emission characteristics of the LED element 1, the distance D, the size of the region where the lens cut is provided, and the processing accuracy. In this example, a total of 10 prisms 6L1, 6L2, 6L3,... 6L10 on the left side with respect to the optical axis A, and a total of 10 prisms 6R1, 6R2, 6R3,. Provide. The left end of the outermost surface of the LED element light emitting unit 1H is HL, and the right end is HR.

  The pitches of the prisms 6L1, 6L2, 6L3, etc. are substantially the same as the width of the LED light emitting unit 1H. Specifically, if the pitch exceeds twice the width of the LED light emitting unit 1H, the size of each of the incident side lens cuts 5 increases, and the unevenness of brightness becomes conspicuous. Similarly, if the ratio is smaller than 0.4 times, each prism becomes small, and the manufacturing cost becomes high to produce a precise prism. More preferably, the size is in the range of 0.8 to 1.2 times the width of the LED light emitting unit 1H. This is because, in this range, the LED element and each prism group can be processed without increasing the cost.

Each prism is as follows. In addition, since it designs symmetrically centering | focusing on the optical axis A, only the left side is demonstrated in the following description.
Each of the prisms 6L1, 6L2, 6L3,... 6L10 is a triangular prism-shaped cut having a triangular cross section along the length direction L (reference plane) of the passage. A left slope 5a and a right slope 5b are provided around each ridgeline 6E. In FIG. 8, only the tenth prism 6L10 on the left side is given a reference numeral. The left slope 5a is preferably set so as to be substantially parallel to each optical path connecting the HL and each ridgeline 6E. In FIG. 8, the left slopes 5a of the 6L3, 6L4, and 6L5 prisms are substantially parallel to the optical paths B3, B4, and B5, respectively. Accordingly, as the distance from the LED element 1 increases, the slope of the prism becomes parallel to the surface of the angle cover 12, that is, approaches L (reference plane). On the other hand, the right slope 5b is constant, for example, 15 degrees with respect to L.

  In this way, the incident-side prism group 6 having a triangular cross section has a plane that has substantially the same acute angle with respect to the reference plane between the entrance-side lens cut and the exit-side lens cut, that is, the right slope 5b (light The left side slope 5a (the right side of the optical axis A), that is, the left side slope 5a (the right side of the optical axis A). On the right side). Thereby, it is possible to easily prevent light flux loss on the prism connection surface.

Next, the exit side lens cut 7 is designed. The exit-side lens cut 7 is a curved prism cut 7L1 over a range corresponding to the first to tenth areas on the left side, and a curved prism cut 7R1 over a range corresponding to the first to tenth areas on the right side. Provide.
The optical path when both the light beam exiting from the HL at the left end and the light beam exiting from the HR at the right end is incident on the incident side lens cut 5 is examined, and the left side entrance side prisms 6L1, 6L2, 6L3 are examined. ... Curvature is set so that the light distribution pattern of 6L10 partially overlaps as shown in FIG. Also, the surface should be smooth based on this curvature. Thus, a convex prism with a continuous curved surface and reduced brightness unevenness can be formed.

  By designing as described above, in the incident side prism group 6, it is possible to prevent light flux loss on the prism connection surface. Further, in the exit side prism group 8, a concave curved portion directly under the light source and a concave curved portion connected to the lens basic thickness are formed at a position farthest from the light source, thereby producing a smooth irradiation pattern. This convex prism has a continuous curved surface, and can realize a light distribution pattern without uneven brightness.

  Thus, according to the present invention, it is possible to obtain an LED lighting device with reduced brightness unevenness without actively providing a reflecting mirror on each LED element 1, and efficiently irradiate the inside of the tunnel. it can. In addition, the lighting device has an advantage that the structure can be simplified because the long life of the LED is utilized and the illumination lamp does not require maintenance, so that the light source does not need to be replaced. In addition, since the light source is close to a point light source, there is an advantage that it is possible to control the light distribution pattern suitable for the illumination device based on the lens cut, which cannot be realized with a fluorescent lamp.

  In addition, by forming the inner reflection part by the lens cut provided in the translucent cover, it is possible to irradiate the lighting device mounting surface without providing additional parts, and it is possible to suppress an increase in cost.

  The present invention is not limited to the embodiment described above. For example, when a plurality of LED elements 1 are closely arranged are used as a light source, the exit side lens cut 7 is provided with a plurality of cuts in the area where the entrance side lens cut 5 is provided, or a diffusion surface is provided in the cylindrical portion. The case where there is no case is also included in the present invention. The present invention can be implemented in various other forms without departing from the spirit or main features thereof.

  INDUSTRIAL APPLICABILITY According to the present invention, the present invention can be applied to tunnel passage illumination lamps including tunnel illumination lamps such as underground waterways, electric / telephone wiring caves, and subways.

DESCRIPTION OF SYMBOLS 1 LED element 2 LED mounting board 5 Incident side lens cut 6 Incident side prism group 7 Outgoing side lens cut 8 Outgoing side prism group 10 Tunnel illumination device 11 LED light source unit 12 Translucent cover 14 Instrument container 15 Air layer 17 Lens element Part 18 Internal space 19 Lighting control device 80 Tunnel 81 Attached tool 82 Passage 83 Wall surface 84, 86 Light distribution pattern 121 Translucent cover bottom part 122 Cylindrical part 123 Inner surface reflection part 124 Main light distribution formation area

Claims (3)

An instrument container, a translucent cover that covers the front of the instrument container, and an LED light source unit that is disposed in an internal space formed by the instrument container and the translucent cover,
The translucent cover is a bottomed cylindrical shape convex toward the front of the instrument direction consisting of a cylindrical part attached to the opening edge of the instrument container and extending forward of the instrument container, and a bottom of the translucent cover,
The LED light source unit has a plurality of LED elements mounted on the substrate surface facing the inner surface of the bottom of the translucent cover,
In front of the optical axis of the LED element at the bottom of the translucent cover, a lens element portion provided with an entrance side lens cut and an exit side lens cut via an air layer,
Among the plurality of LED elements mounted on the LED light source unit, the optical axis of the LED element close to the cylindrical portion of the transparent cover, and the bottom of the transparent cover positioned between the LED element and the cylindrical portion The tunnel illumination device is characterized in that an inner surface reflection portion that reflects toward the tube portion is formed.   The inner surface reflection portion includes an incident surface facing the LED element having a triangular cut cross section provided on the inner surface of the bottom portion of the translucent cover, and a reflection surface positioned outside the bottom portion of the translucent cover, 2. The tunnel illumination according to claim 1, wherein light incident from the incident surface and reflected by the reflecting surface is reflected obliquely toward the rear side of the instrument container through the cylindrical portion. apparatus. The incident side lens cut comprises a prism group having a triangular cross section parallel to the incident side lens cut located in front of the other LED elements,
The exit side lens cut constitutes an uneven prism made of a continuous curved surface within a range corresponding to the prism group of the corresponding entrance side lens cut,
In the lens element portion, the entrance side lens cut and the exit side lens cut are integrally formed of a translucent resin,
The incident side lens cut triangular prism group has a plane that is substantially the same acute angle with respect to a reference plane between the incident side lens cut and the output side lens cut, and a plane orthogonal to the reference plane. The tunnel illumination device according to claim 2, wherein the tunnel illumination device has a plane having an acute angle that increases with distance from the LED element.

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