Display mechanism

Abstract

To provide an energy-saving display machine and traffic signal capable of preventing snow accumulation efficiently with a simple structure.SOLUTION: On a light emission surface side of a light source 5 in a light source installation part 3, a transparent cover 9 for protecting the light source 5 is arranged on a rail. A method for fixing the rail and the transparent cover 9 is not particularly limited. The transparent cover 9 is a triangle pole member having a substantially triangular portion protecting forward, in a cross sectional shape vertical to a longitudinal direction. Also, the light source 5 is a plane type LED light source, and a flat surface on a rear surface side of the transparent cover 9 is in surface contact with a light emission surface of the LED light source.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an indicator, such as a traffic signal, capable of preventing snow from accumulating, particularly in snowy regions. [Background technology]

[0002] In recent years, with the change in the global environment, damage caused by heavy snow blown by strong winds in winter has become a problem. Heavy snowfall not only creates obstacles to road traffic, but also causes snow to accumulate on traffic signal lamps due to blizzards, blocking the light emission of traffic signals and making the traffic signals invisible. For this reason, measures against snow accumulation on traffic signals during blizzards are desired.

[0003] One method of preventing snow accumulation is to provide a hood or cover to cover the traffic light (see, for example, Patent Document 1 and Patent Document 2).

[0004] There is also a method of melting snow using a heating element (eg, Patent Document 3 and Patent Document 4).

[0005] However, while methods such as those described in Patent Documents 1 and 2 that provide large hoods or the like may make it more difficult for snow to accumulate, once snow does accumulate, the area where it has accumulated will continue to grow, impairing the visibility of the traffic light.

[0006] Furthermore, when infrared rays are used as a heat source as in Patent Document 3, electrical energy is converted into light, which results in poor efficiency in conversion and absorption, and the difficulty of requiring an extremely large amount of electrical energy to generate sufficient heat to remove snow from the light-emitting surface.

[0007] Furthermore, Patent Document 4 provides a cover to form a dark portion that absorbs light, which is a heat source, and generates heat. However, this has problems in that it is inefficient when using light as an energy transmission means, and covering the traffic light with such a material impedes visibility under normal circumstances.

[0008] In response to this, a display has been proposed in which multiple light source arrangement sections are arranged at a predetermined interval so that wind and snow from the front can pass through the gaps between adjacent light source arrangement sections to the rear (Patent Document 5). [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2008-305025 A [Patent Document 2] Publication No. 2009-190554 [Patent Document 3] Utility Model Registration No. 3161877 [Patent Document 4] JP 2012-108861 A [Patent Document 5] Patent Publication No. 2021-26658 Summary of the Invention [Problem to be solved by the invention]

[0010] According to Patent Document 5, snow blown from the front passes through the gaps between adjacent light source arrangement sections to the rear, so by appropriately setting the gaps between the light source arrangement sections, it is possible to prevent snow from accumulating on the front surface of the light source arrangement sections. However, if even a small amount of snow adheres to the front surface of the light source arrangement section, there is a risk that the snow accumulation area will expand from this nucleus.

[0011] In addition, the width of the light source arrangement section cannot be made wide because a gap must be provided between adjacent light source arrangement sections through which wind and snow can pass. Therefore, there is a limit to the size of the light source 5 arranged in the light source arrangement section, and it is desirable to have a function of effectively collecting and distributing the total luminous flux emitted from the light source.

[0012] The present invention has been made in consideration of such problems, and aims to provide an indicator and a traffic light that are energy-saving, have a simple structure, efficiently prevent snow accumulation, and are capable of distributing signal light. [Means for solving the problem]

[0013] In order to achieve the above-mentioned object, the present invention provides a display comprising a light source arrangement section in which a light source is arranged, a transparent cover provided on the light-emitting surface side of the light source arrangement section and protecting the light source, and a frame section supporting the light source arrangement section, wherein the multiple light source arrangement sections are arranged at predetermined intervals, wind and snow from the front can pass through gaps between adjacent light source arrangement sections to the rear, and the transparent cover is a triangular prism-shaped member having an approximately triangular portion protruding forward in a cross-sectional shape perpendicular to the longitudinal direction.

[0014] The transparent cover may be substantially in the shape of a home plate, having side portions that are substantially parallel to each other in the front-rear direction and are positioned rearward of the triangular portion.

[0015] It is desirable that the angle of the front apex of the transparent cover be approximately 100° or less.

[0016] It is preferable that the light source is a flat LED light source, and the rear surface of the transparent cover is in surface contact with the light emitting surface of the LED light source.

[0017] According to the present invention, gaps are formed between adjacent light source arrangements, and wind can pass through the gaps. Since the transparent cover has a generally forward-facing triangular shape, the area of ​​stagnation points of the wind flow in front of the light source arrangements is reduced, and snow accumulation on the front surface of the light source arrangements can be reduced. In addition, the light emitted from the LED light source is focused forward due to the lens effect caused by the light refraction through both slopes of the triangular shape. Due to this effect, the internal light source appears to be expanded when viewed from the front, thereby improving visibility.

[0018] Furthermore, if the angle of the front apex of the transparent cover is approximately 100° or less (i.e., the base angle of the isosceles triangle is approximately 40° or more), it will be greater than the angle of repose of snow, and snow accumulation on the left and right slopes can be more reliably suppressed.

[0019] In addition, by using a flat LED light source as the light source and bringing the rear surface of the transparent cover into surface contact with the light-emitting surface of the LED light source, the light emitted from the light source can be efficiently guided into the triangular prism-shaped transparent cover, improving visibility from the front. Effect of the Invention

[0020] According to the present invention, it is possible to provide a display device and a traffic signal that are energy-saving and can efficiently prevent snow accumulation with a simple structure. [Brief description of the drawings]

[0021] [Figure 1] 1A is a front view of a traffic light 10, and FIG. 1B is a cross-sectional view of the traffic light 10 taken along line BB in FIG. [Diagram 2] FIG. 4A is an enlarged cross-sectional view of the light source installation section 3, and FIG. 4B is a diagram showing the flow of air etc. relative to the light source installation section 3. [Diagram 3] 13A and 13B are diagrams showing different shapes of the transparent cover, and 13C and 13D are conceptual diagrams showing the visibility of the light source 5 when viewed from the front. [Figure 4] Actual photographs of Figures 3(c) and 3(d). [Diagram 5] 4(a) and (b) are diagrams showing the light distribution characteristics of a light source 5 for FIG. 3(a) and FIG. 3(b). [Figure 6] 13(a) and (b) are diagrams showing another transparent cover 9b. [Figure 7] FIG. 4A is a perspective view showing the display unit 1a, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1(a) is a front view of a traffic light 10, and FIG. 1(b) is a cross-sectional view of the traffic light 10, taken along line BB in FIG. 1(a). In the following description, an example of a traffic light 10 in which three indicators 1 are connected is described, but the indicators 1 of the present invention may be connected vertically or may be a double traffic light. In addition to traffic lights, the indicators 1 can be used as indicators for toll gates on expressways, or indicators for displaying traffic information, warnings, indicators for toll gates on expressways, signs, etc. The indicator 1 is mainly composed of a light source arrangement section 3, a light source 5, a frame section 7, etc.

[0023] In the light source arrangement section 3, a plurality of light sources 5 are arranged in the longitudinal direction. The light sources 5 are, for example, LED light sources. In the illustrated example, the light sources 5 are arranged in a row in each light source arrangement section 3, but they may be arranged in two or more rows. However, as will be described later, if the width of the light source arrangement section 3 is widened, the amount of snow that accumulates may increase, so it is preferable that the width of the light source arrangement section 3 is narrow.

[0024] The light source arrangement sections 3 are arranged parallel to each other at a predetermined interval. In the illustrated example, the light source arrangement sections 3 are arranged in a vertical lattice pattern. The frame section 7 supports the light source arrangement sections 3 at least at the upper and lower parts of the light source arrangement sections 3. In this way, gaps are formed between the light source arrangement sections 3, so that a snowstorm from the front can pass through the gaps between the adjacent light source arrangement sections 3 to the rear. Note that the formation of gaps between the adjacent light source arrangement sections 3 means that there is a space between the adjacent light source arrangement sections 3 through which wind can pass. For example, the light source arrangement sections 3 may be partially connected to each other, and a part between the light source arrangement sections 3 may be blocked. Note that the details of the flow of the air current will be described later.

[0025] A plurality of light sources 5 are arranged in each light source arrangement section 3. Since the light source arrangement sections 3 are of approximately the same length and arranged at a predetermined interval, the light emitting area in which the light sources 5 can be installed is approximately rectangular. In the plurality of light source arrangement sections 3 arranged in such an approximately rectangular shape, the light sources 5 are arranged so as to form an approximately circular shape when viewed from the front (A in the figure). In this way, light is emitted in an approximately circular shape, which can be recognized as circular light.

[0026] It should be noted that there is also a method of covering the area other than the circular light-emitting area with a shielding plate or the like, but in this case, the shielding plate fills the gap between adjacent light source arrangement sections 3. As a result, the shielding plate prevents the flow of fluid (wind and snow) between adjacent light source arrangement sections 3. For this reason, it is preferable to form a substantially circular light-emitting area by arranging the light sources 5 in the light source arrangement section 3, rather than blocking a portion of the light source arrangement section 3.

[0027] 2(a) is an enlarged cross-sectional view of the light source mounting section 3. In the light source mounting section 3, for example, a board on which the light sources 5 are arranged is joined onto a rail having a substantially H-shaped cross section. In addition, a transparent cover 9 for protecting the light sources 5 is disposed on the light-emitting surface side of the light sources 5 in the light source mounting section 3 and is integrated therewith.

[0028] The transparent cover 9 is a triangular prism member (excluding hollow members) having a substantially triangular portion (dotted line in the figure) protruding forward in a cross section perpendicular to the longitudinal direction. The light source 5 is a flat LED light source, and the flat surface on the rear side of the transparent cover 9 is in surface contact with the light emitting surface of the LED light source. In other words, there is no light reflecting surface between the emission surface of the light source 5 and the front surface of the transparent cover 9. By eliminating the air layer between the light source 5 and the transparent cover 9 in this way, the light emitted from the light source 5 can be efficiently introduced into the transparent cover 9. The transparent cover 9 can be made of resin or glass with a refractive index greater than 1.

[0029] In the illustrated example, the transparent cover 9 has a triangular portion (dotted line portion in the figure) at the front where a slope portion 15 is provided from the center to the rear, and a side portion 13 that is approximately parallel in the front-to-rear direction (left-to-right direction in the figure) behind the base of the isosceles triangle. That is, in the illustrated example, the transparent cover 9 has a shape that is approximately like a home plate, where an isosceles triangle with an apex angle facing forward is connected to a rectangle provided behind it. The side portion is parallel to the air flow and is not subject to snow accumulation. Even if snow accumulates on the top of the front surface during a heavy snowstorm, light emitted from the side portion radiates a signal light.

[0030] Here, it is desirable that the base angle (θ in the figure) of the transparent cover 9 is approximately 40° or more. For example, in places where there is a surface perpendicular to the flow of snowstorm, the flow stops and loses speed, creating stagnation points, which serve as nuclei for snow particles to adhere to the surface of the object. At this time, the outline of the snow forms an angle of repose, which has been reported to be approximately 40° (see "Transition of Road Icing Prevention Technology (2) Snowstorm Countermeasures for Ensuring Traffic and Safety: Research and Technology" by Takeuchi Masao, Kita no Kousaten vol. 3, SPRING-SUMMER 1998, pp. 10-17; "Experimental Study on Snow Accretion Properties on Structural Members - Snow Particle Collision Rate and Snow Accretion Rate" by Sato Yuki et al., Hokkaido University of Science Research Bulletin No. 39 (2015) pp. 1-6; "Snow Accretion on Road Signs and Prevention" by Takeuchi Masao et al., Civil Engineering Laboratory Monthly Bulletin, October 1978, No. 305, pp. 11-19).

[0031] That is, if the base angle of the transparent cover 9 is approximately 40° or more, snow accumulation on the slope portion 15 can be suppressed.

[0032] Fig. 2(b) is a diagram showing the airflow (C in the figure) from the front (left side in the figure) of the light source arrangement section 3. If a surface approximately perpendicular to the airflow exists at the tip of the approximate center of the light source arrangement section 3, a stagnation point where the airflow speed is approximately 0 is formed at the site where the airflow collides (D2 in the figure). At stagnation point D2, the light source arrangement section 3 is pushed by the flow due to the dynamic pressure and the action of converting the kinetic energy of the snow particles into thermal energy.

[0033] For example, in a snowstorm containing snow particles, snow particles that reach the stagnation point D2 collide with the light source arrangement section 3 and are pressed against the light source arrangement section 3 by dynamic pressure, causing snow to accumulate, which is thought to result in a large amount of snow accumulating at the stagnation point and in its vicinity.

[0034] However, in this embodiment, the stagnation point D2 is the apex of a triangle, so the area of ​​the surface approximately perpendicular to the airflow is extremely small (ideally, the apex is a ridge line with an area of ​​0). This makes it possible to prevent snow from accumulating at the stagnation point. As described above, the base angle of the slope 15 with respect to the base is greater than the angle of repose, and wind-blown snow flows backward, so even if a small amount of snow accumulates on the apex of the transparent cover 9, further growth of the snow is prevented.

[0035] Next, the visibility of the light emitted from the light source will be described. Fig. 3(a) is a diagram showing a light source arrangement section 3 using a transparent cover 9a having a surface approximately perpendicular to the air flow described above as a comparative example, and Fig. 3(b) is a diagram showing a light source arrangement section 3 using a transparent cover 9 having a triangular front (isosceles triangle with an apex angle of 90°). Note that Fig. 3(b) shows an example in which the inclined surface is flat, but the same is true even if the inclined surface is curved forward. That is, the same tendency is observed even if the inclined surface has a gentle arc shape that is convex forward near the approximate center in the width direction (left-right direction in the figure).

[0036] FIG. 3(c) is a diagram showing how the light source 5 looks when viewed from the front (arrow C) of FIG. 3(a), and FIG. 3(d) is a diagram showing how the light source 5 (light from the light source 5) looks when viewed from the front (arrow D) of FIG. 3(b). As shown in FIG. 3(c), when the front surface of the transparent cover 9a is flat (or a gentle arc), the light-emitting area of ​​the light source 5 seen through the transparent cover 9a from the front (E in the figure) is visually recognized as being approximately the same size as the size of the light source 5. On the other hand, as shown in FIG. 3(d), when the transparent cover 9 has a triangular shape protruding forward, the light-emitting area of ​​the light source 5 is visually recognized on both sides of the center (apex) in the width direction due to refraction of light when it is emitted from the triangular prism into the atmosphere. That is, the area of ​​light from the light source 5 seen through the transparent cover 9 (F in the figure) is sufficiently larger than the size of the original light source 5.

[0037] The photograph on the left side of Fig. 4 is an actual photograph corresponding to Fig. 3(c), and the photograph on the right side of Fig. 4 is an actual photograph corresponding to Fig. 3(d). By making the front of the transparent cover 9 triangular in this way, the light emitting area (size) of the light source 5 seen from the front can be made approximately twice as large.

[0038] By collecting light forward from each light source arrangement section 3, adjacent light source arrangement sections 3 become a group that emits signal light forward. In this case, it is possible to significantly improve visibility while saving power without changing the number of light sources 5 or power consumption.

[0039] Fig. 5(a) is a diagram showing the evaluation results of the light distribution characteristics of the light emitted from the light source 5 with the transparent cover removed (roughly corresponding to the left side of Fig. 4). Also, Fig. 5(b) is a diagram showing the evaluation results of the light distribution characteristics of the light emitted from the light source 5 with a triangular prism-shaped transparent cover 9 attached (corresponding to the right side of Fig. 4). The LED light source consisted of 15 LED elements mounted at equal intervals on an aluminum rail 25 cm long and 12 mm wide, and driven at 12 V. The height of the center of the light source and the illuminometer were set to be the same, and the measurement distance was 1 m.

[0040] As shown in the figure, in either case, the intensity of the light emitted from the light source 5 is stronger toward the center and becomes weaker as the light distribution angle becomes larger, but in FIG. 5(b) where a triangular transparent cover 9 is used, the light toward the front is stronger. In other words, by using a triangular prism transparent cover 9, the light spreading to the left and right is concentrated in the center (forward), and the brightness at the center is about twice as high as that of the comparative example. In addition, in FIG. 5(b), the angle range where the brightness was equal to or greater than that of FIG. 5(a) was about 60° (a range of 30° to the left and right from the center).

[0041] As described above, according to this embodiment, by making the front surface of the transparent cover 9 into a triangular prism shape, it is possible to minimize stagnation points and suppress the adhesion of snow, which becomes the nucleus for the initial stage of snow accumulation.

[0042] Moreover, by setting the inclination angle of the sloped portion 15 of the transparent cover 9 to be equal to or greater than the angle of repose, it is possible to further suppress snow accumulation on the left and right slopes of the transparent cover 9. Also, since the structure is such that wind and snow can blow through between the multiple light source arrangement sections 3 where the light sources 5 are arranged, snow accumulation on the light emitting surfaces of the light source arrangement sections 3 is significantly reduced, making it possible to eliminate snow accumulation.

[0043] Moreover, since the intensity of the light from the light source 5 when viewed from the front can be increased, visibility from the front can be improved.

[0044] In order to obtain such an effect, the shape of the transparent cover is not limited to the home plate type, and for example, a transparent cover 9b having an overall triangular prism shape as shown in Fig. 6 may be used. In this way, as long as it has a triangular prism shape protruding forward, the cross-sectional shape is not particularly limited.

[0045] Next, another embodiment will be described. Fig. 7(a) is a rear perspective view showing the display device 1a, and Fig. 7(b) is a side view of the display device 1a (a perspective view of the frame, etc.). In the following description, components having the same functions as those in the above-mentioned embodiment are given the same reference numerals as those in Figs. 1 to 3, and duplicated description will be omitted.

[0046] The display 1a has a configuration similar to that of the display 1, but is different in that a light shielding member 17 is additionally arranged behind the light source arrangement section 3 so that wind can pass through. In the display 1a, a plurality of light shielding members 17 are arranged in a plurality of stages. In the figure, an example in which the light shielding members 17 are arranged in three stages is shown, but the number of stages of the light shielding members 17 is not particularly limited. The plurality of light shielding members 17 are arranged at a predetermined interval in the vertical direction. Each light shielding member 17 has a tapered portion that is inclined downward as it goes rearward, and the tapered portions are formed approximately parallel to each other. In a rear view (front view), the plurality of stages of light shielding members 17 are arranged so as to overlap each other in the vertical direction. For example, the lower end of the upper stage light shielding member 17 overlaps in height with the upper end of the light shielding member 17 in the stage below.

[0047] The tapered portions of all the light blocking members 17 are formed at positions spaced a predetermined distance rearward from the frame portion 7. The uppermost light blocking member 17 has a horizontal portion (a portion substantially perpendicular to the direction in which the light source arrangement portions 3 are arranged) in front of the tapered portion, and an eave is formed so as to protrude forward of the frame portion 7. In other words, the light blocking members 17 from the second row onwards from the top are disposed at positions spaced a predetermined distance rearward from the frame portion 7.

[0048] Each light blocking member 17 is supported by a frame arranged rearward from the side of the frame 7. That is, the light blocking members 17 are fixed to the frame 7 via the frame. In the illustrated example, the frame is exposed on the side, but the side of the light blocking member 17 may be blocked by a plate-like member (not shown) or the like.

[0049] As described above, because a gap is formed between adjacent light source arrangement sections 3, it is possible to see the scenery behind the display unit and sunlight from behind from the front of the display unit. This may impair the visibility of the light emitting unit in front of the display unit. In response to this, by disposing the light blocking member 17, light from the rear of the display unit 1a is blocked, and the visibility of the light from each light source 5 of the light source arrangement section 3 can be improved.

[0050] In addition, the multiple light blocking members 17 are arranged with gaps between them, so that the wind passing between the adjacent light source arrangements 3 can flow directly to the rear of the display unit 1a. Therefore, even if light from the rear is blocked, the flow of wind is not impeded. Therefore, snow accumulation on the front surface of the light source arrangements 3 can be suppressed.

[0051] The arrangement and shape of the light blocking member are not limited to the example shown in Fig. 7. Any other shape may be used as long as it can block light from behind and allow air to flow backward.

[0052] As described above, according to this embodiment, by disposing a light-blocking member that blocks light behind the display unit, it is possible to prevent light from leaking from behind the display unit through gaps between adjacent light source arrangement parts 3. In addition, since there is a gap between the light-blocking member 17 and the frame part 7, it is possible to maintain the snow accumulation suppression effect without blocking the air flow.

[0053] Although the embodiment of the present invention has been described above with reference to the attached drawings, the technical scope of the present invention is not limited to the above-described embodiment. It is clear that a person skilled in the art can think of various modifications or alterations within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0054] 1, 1a……Display device 3……Light source installation part 5……Light source 7...Frame 9, 9a, 9b………Transparent cover 10. Traffic light 13……Side part 15....Slope section 17....Light blocking member

Claims

1. a light source arrangement section in which a light source is arranged; a transparent cover provided on a light emitting surface side of the light source arrangement portion to protect the light source; A frame portion supporting the light source arrangement portion; Equipped with The light source arrangement sections are arranged at predetermined intervals, and wind and snow from the front can pass through gaps between adjacent light source arrangement sections to the rear, A display device characterized in that the transparent cover is a triangular prism member having a generally triangular portion protruding forward in a cross section perpendicular to the longitudinal direction.

2. 2. The display device according to claim 1, wherein the transparent cover is substantially in the shape of a home plate and has side portions that are substantially parallel to each other in the front-rear direction and are positioned rearward of the triangular portion.

3. 2. The display according to claim 1, wherein the angle of the front apex of said transparent cover is less than 100 degrees.

4. 2. The display according to claim 1, wherein the light source is a flat LED light source, and the rear surface of the transparent cover is in surface contact with a light emitting surface of the LED light source.

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