JP5059145B2 - Snow prevention device for signal lights - Google Patents

Description

The present invention relates to an improvement in a snow accretion prevention device that melts snow adhering to the surface of a signal lamp.

A lot of signal lights are installed along the roads and railway tracks in the snowy area, but the snow piled up on the signal light hood cover hangs down in front of the signal lights and obstructs the front, resulting in poor visibility is there. For this reason, there is an apparatus (Patent Document 1) in which a heating element is attached on the hood cover, and the snow is melted by heating the hood cover by energizing the heating element by a signal from a snow accumulation sensor.

However, there is a problem that the visibility is deteriorated when snow blown up or snow rolled up when passing through the train directly adheres to the lens surface of the signal lamp. For this reason, it is also considered to melt the attached snow by forming the glass on the lens surface with glass containing heat rays sandwiching a heating wire. This hot-wired glass has a maximum temperature of only about 50 ° C, and it takes about 60 minutes to reach the maximum temperature, so it lacks immediate effect, and in places where the outside air temperature is below 30 ° C below freezing, There was a problem that the surface temperature did not rise and snow could not be prevented. Also, in order to increase the surface temperature of the glass, if the amount of electricity applied to the heating wire is increased to a high temperature, the heating wire glass is in close contact with the glass, so when it reaches 180 ° C or higher, it locally becomes hot and expands. There was a problem that the glass broke and it could not be put into practical use.

For this reason, the present inventor first developed a signal light snow-prevention device (Patent Document 2) shown in FIGS. In this case, three circular window frames 3A are vertically attached to the front surface of a hollow flat metal case 2 having a semicircular upper portion, and the back surface of the metal case 2 is as shown in FIG. A rectangular window frame 3B having a semicircular upper portion is attached. Three circular heat-resistant glass plates 4A are fitted in the three circular window frames 3A on the front surface of the case, respectively, and one heat resistant glass plate 3B is formed on the upper surface of the window frame 3B on the rear surface of the case. The glass plate 4B is fitted and a sealed space is formed.

In addition, three infrared heaters 7 are attached in the horizontal direction at a position avoiding the window frame 3A between the circular window frames 3A and 3A adjacent to each other in the hollow flat metal case 2 and the inner bottom portion. ing. Further, the signal lamp 13 has three lamps 15 of red, yellow and blue arranged in the vertical direction on the front surface, and a back plate 16 is attached so as to surround the lamp 15 so that the lamp 15 is surrounded on the front surface of the back plate 16. A hood cover 14 is attached. The snow accretion prevention device 1 is attached to the inside of the hood cover 14.

As shown in FIG. 6, the snow accretion prevention device 1 generates heat when the infrared heater 7 is energized during snowfall, and heats air in a narrow space in the metal case 2 formed in a hollow flat plate shape. When the air in the metal case 2 is heated, the heat-resistant glass plates 4A and 4B are also heated and radiate heat from the surface, but the surface temperature of the heat-resistant glass plates 4A and 4B is maintained at, for example, 5 ° C. or higher. When the temperature is set, the snow adhering to the surface is melted to prevent adhesion.

Further, since the hood cover 14 is attached so as to surround the front and side of the lamp 15, snow does not enter during this period. As a result, the light of the lamp 15 of the signal lamp 13 can be seen from a distance through the two heat-resistant glass plates 4A and 4B before and after the snow accretion prevention device 1.

Thus, since the air in the narrow space in the metal case 2 having a hollow flat plate shape is heated by the infrared heater 7, it is efficiently heated in a short time, and the heat-resistant glass plates 4A and 4B are made uniform uniformly by the heated air. It is heated and the glass surface is not locally heated and damaged as in conventional glass with hot wire, and the snow adhering to the surface when heated to a high temperature can be rapidly melted.

However, as a result of the experiment, as shown in FIG. 7, when the outside air temperature is low, the snow melted on the front surface of the heat-resistant glass plate 4A flows as water droplets, freezes at the bottom corner of the metal case 2, and the icicles 18 are formed. Then, it flows to the signal lamp 13 side along the bottom surface and freezes at the corner portion to generate the ice column 18. Once the icicle 18 is generated, the snow 19 adheres to it and gradually grows, causing a problem of covering the front surface of the lowermost heat-resistant glass plate 4A.

When this cause was investigated, since the metal case 2 is formed in a vertically long hollow flat plate shape, the air heated by the infrared heater 7 rises and the temperature on the bottom side of the metal case 2 does not rise. Further, since there is a gap between the bottom of the metal case 2 and the bottom of the signal lamp 13, cold air enters from here and is cooled, and the temperature on the bottom side of the metal case 2 does not rise, and the ice column 18 is generated here. This is probably because of this.

JP 2003-303399 A JP 2008-305025 A

The present invention improves the above problem, and even in the event of a snowstorm at temperatures below 30 ° C., it prevents snow from landing on the lamp and prevents the formation of icicles at the bottom of the metal case, thereby ensuring visual recognition of the lamp. It is an object of the present invention to provide a snow light prevention device for a signal light.

According to a first aspect of the present invention, there is provided an apparatus for preventing snow accretion of a signal lamp, wherein a window frame is formed on the front and rear surfaces of a hollow flat metal case, and a heat resistant glass plate is attached to the window frame to seal the inside of the metal case This metal case is attached to the inside of a hood cover joined to the front of a signal lamp having a plurality of lamps attached in the vertical direction, and the inside of the metal case is divided into a plurality of parts corresponding to the lamps of the signal lamp, and each divided space An electric heater is attached to the bottom side of each part, and the bottom part side of the space part located at the lowermost part is enlarged to the signal lamp side so as to form a side L-shaped space part so as to substantially close the gap between the lower part of the signal lamp. The air in each space is heated to a high temperature with an electric heater in the metal case, and the snow adhering to the heat-resistant glass plate on the front surface of the metal case is melted.

According to Claim 2 of the present invention, the snow-prevention device for signal lights according to Claim 1 is characterized in that an electric heater wire is joined to the inside of the hood cover to heat the hood cover. .

According to a third aspect of the present invention, there is provided an apparatus for preventing snow accretion of a signal lamp according to the first aspect, wherein a window frame corresponding to each of the lamps of the signal lamp is formed in a circle on the front and rear surfaces of the metal case. It is characterized by having attached.

According to a fourth aspect of the present invention, there is provided the signal light snow-prevention device according to the first aspect, wherein the front surface of the metal case is inclined forward and attached to the hood cover.

According to a fifth aspect of the present invention, there is provided an apparatus for preventing snow accretion of a signal lamp according to the first aspect, wherein the electric heater is an infrared heater in which a heating wire is inserted into a glass tube. It is characterized by being attached at a position avoiding the window frame portion of each space portion.

According to a sixth aspect of the present invention, the snow-prevention device for a signal lamp according to the fifth aspect is characterized in that the surface of the glass tube of the infrared heater is painted black.

According to the snow-prevention device for signal lamps according to claim 1 of the present invention, the hood cover is attached to the front of the signal light so as to surround the lamp, and the snow-prevention device is attached to the front of the lamp inside the hood cover, Since the inside of the metal case of the snow accretion prevention device is divided into a plurality of spaces and each is provided with an electric heater, the air in each space can be rapidly and efficiently heated by the electric heater. Furthermore, since the bottom side of the lowermost space is enlarged to the signal lamp side and formed into a side L shape, the gap between the signal lamp and the signal lamp is closed by the heated space. The water droplets that have flowed down with a small amount can be dropped without becoming icicles, and the problem that the front surface of the heat-resistant glass plate at the bottom is covered with snow can be solved.

According to the signal light snow accretion prevention device according to claim 2, since the electric heater wire is joined to the inside of the hood cover so as to heat the hood cover, the snow accumulated thereon is melted into water droplets. It falls and grows in the shape of a comb and prevents the front of the heat-resistant glass plate from being covered with icicles and snow.

According to the snow prevention device for a signal lamp according to claim 3, since the window frame corresponding to the lamp of the signal lamp is formed in a circle on the front and rear surfaces of the metal case, and a circular heat-resistant glass plate is attached thereto, The area of the metal part of the metal case having better heat conductivity than that of glass is widened, and each space part can be rapidly heated.

According to the signal light snow accretion prevention device of claim 4, since the front surface of the metal case of the snow accretion prevention device attached to the inside of the hood cover is attached to be inclined forward, The reflected sunlight is reflected downward and is not dazzling.

According to the snow-prevention device for a signal lamp according to claim 5, the electric heater is formed by an infrared heater in which a heating wire is inserted into a glass tube, and the infrared heater is used as a window in each space portion of a sealed metal case. Since it is attached at a position that avoids the frame portion, the space can be rapidly heated and the visibility of the signal lamp can be maintained.

According to the snow prevention device for a signal lamp according to claim 6, black paint is applied to the surface of the glass tube of the infrared heater so as to prevent light from the heating lines from leaking into each space portion. Therefore, the light transmission of the lamp is not hindered and the visibility can be improved.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. The signal lamp 13 has three lamps 15 of red, yellow, and blue arranged in the vertical direction on the front side, and a back plate 16 is attached so as to surround the lamp 15, and a hood so as to surround the lamp 15 on the front surface of the back plate 16. A cover 14 is attached. A snow accretion prevention device 10 is attached to the inside of the hood cover 14.

This snow accretion prevention device 10 is formed of an aluminum plate, a stainless steel plate or the like, and has three circular window frames 3A on the front surface of a hollow flat metal case 2 whose upper portion is semicircular as shown in FIG. Are vertically spaced. In addition, as shown in FIG. 2, three circular window frames 3B are similarly attached to the back surface of the metal case 2 at intervals in the vertical direction. Circular heat-resistant glass plates 4A and 4B are fitted into the three circular window frames 3A and 3B on the front and rear surfaces of the case, respectively. The heat-resistant glass plates 4A and 4B attached to the window frames 3A and 3B are arranged so as to be positioned in front of the three lamps 15 of the signal lamp 13, and the lamp 15 is viewed from the front through the heat-resistant glass plates 4A and 4B. Appears to be transparent. As the heat-resistant glass plates 4A and 4B, those having heat resistance to such an extent that the glass surface is not damaged at a temperature of 600 ° C. or lower when heat is applied in a planar shape are used.

Further, a partition plate 20 is provided between the upper and lower circular window frames 3A, 3A in the hollow flat metal case 2, and three space portions 21A, 21B, 21C are formed. As shown in FIG. 3, the bottom side of the space portion 21 </ b> C located at the lowermost portion is enlarged to the signal lamp 13 side to form a side face L shape, and has a shape that substantially closes the gap between the signal lamp 13. Further, a rounded portion 23 is formed at the lower front corner of the metal case 2 constituting the space portion 21 </ b> C formed in the side face L shape.

Infrared heaters 7 are respectively attached to the inner bottom portions of the space portions 21A, 21B, and 21C at positions avoiding the window frames 3A and 3B in the lateral direction. As shown in FIG. 4, the infrared heater 7 has heating wires 5 such as carbon fiber and nichrome wire mounted in a heat-resistant glass tube 6 having a hollow cylindrical shape, and connection terminals 8 are attached to the left and right ends thereof. The connection terminal 8 is connected to a power source (not shown) via a lead wire.

A black paint 12 is applied to the surface of the glass tube 6 to shield the light from the heating wire 5 from leaking into the space portions 21A, 21B, and 21C. A temperature sensor 11 is provided in the uppermost space portion 21A, which is connected to a control device (not shown). When the temperature in the metal case 2 becomes, for example, 100 ° C. or less, the power switch is turned on and the infrared heater 7 is turned on. When energized and exceeds 200 ° C., the power switch is turned off and the infrared heater 7 is stopped.

Further, as shown in FIG. 2, an electric heater wire 24 is meandered and attached to the inside of the hood cover 14 so as to heat the hood cover 14. The snow accretion prevention device 10 attached to the inside of the hood cover 14 is attached such that the front surface of the metal case 2 is inclined forward.

In the signal light snow prevention device 10 configured as described above, when a power source (not shown) is turned on and the infrared heater 7 is energized during snowfall, the heating wire 5 generates heat and the narrow space portions 21A, 21B, 21C in the metal case 2 are heated. While the air is heated, the heat-resistant glass plates 4A and 4B are rapidly heated by the radiant heat. Therefore, the conventional metal case 2 shown in FIG. 6 causes a temperature difference between the upper and lower sides due to convection, and in particular, the temperature on the lower side does not easily rise. However, the present invention divides the inside of the metal case 2 into three and narrow space portion 21A. 21B and 21C are formed, the temperature difference between the upper and lower sides is small, and in particular, the temperature of the lowermost space portion 21C can be kept higher than in the prior art. Further, the heat-resistant glass plate 4B on the back side is formed in a circular shape, and the area of the metal portion of the metal case 2 having good thermal conductivity is larger than that of glass, so that the space portions 21A, 21B, and 21C are rapidly heated. be able to.

Further, since the surface of the heat-resistant glass plate 4A heated from the inside is exposed to the outside air, heat is radiated from this surface. When the signal lamp 13 is installed in a place below the freezing point of 30 ° C. or less, if the temperature of the infrared heater 7 is set so that the surface temperature of each of the heat-resistant glass plates 4A and 4B is maintained at, for example, 5 ° C. or more, it adheres to the surface. Snow is melted to prevent adhesion. Further, as shown in FIG. 2, a hood cover 14 is attached so as to surround the front and sides of the lamp 15, and the bottom side of the space portion 21C located at the lowermost portion is enlarged to the signal lamp 13 side to form a side L shape. Since the gap between the lower portion of the signal lamp 13 and the lower portion of the signal lamp 13 is substantially closed, it is possible to prevent snow from entering the space in front of the lamp 15 and lowering the temperature.

Further, since the rounded portion 23 is formed in the lower corner of the front surface of the metal case 2 constituting the space portion 21C formed in the side surface L shape, and there is no pointed portion as shown in FIG. And can prevent the formation of icicles. Further, the bottom side of the space 21C is enlarged to the side of the signal lamp 13 and formed into a side face L shape, and the gap between the signal lamp 13 and the heated space is closed. Water droplets that have flowed down little can be dropped without becoming icicles. As a result, the ice column on the bottom side of the space portion 21C is not generated, and snow is attached thereto due to the growth of the ice column, and the problem of covering the front surface of the lowermost heat-resistant glass plate 4A can be solved.

Further, as shown in FIG. 2, an electric heater wire 24 is meandered and attached to the inside of the hood cover 14 so as to heat the hood cover 14, so that the snow accumulated thereon is melted into water droplets and Therefore, it can be prevented from growing in the shape of a comb and covering the front surface of the snow accretion prevention device 10.

Further, as shown in FIG. 4, a black paint 12 is applied to the surface of the glass tube 6, and the light from the heating wire 5 is shielded so as not to leak into the space portions 21A, 21B, 21C. Transmission of 15 light is not hindered. Further, the snow accretion prevention device 10 attached to the inside of the hood cover 14 is attached so that the front surface of the metal case 2 is inclined forward, so that the sunlight reflected by the heat-resistant glass plate 4A is reflected downward and is dazzling. Absent.

Moreover, since the vehicle passing time is fast in the on / off operation of the snowfall sensor, the snowfall prevention device 10 of the present invention is not in time for the snowfall sensor alone, but the temperature sensor 11 causes the surface temperature of the heat-resistant glass plate to melt, for example. Since the temperature is constantly maintained at 5 ° C. or higher, it is possible to prevent the lamp 15 of the signal lamp 13 from snowing regardless of the vehicle transit time and the operation interval.

As a result, even in the event of a heavy snowstorm, the light of the lamp 15 of the signal lamp 13 can be seen from a distance through the two heat-resistant glass plates 4A and 4B before and after the snow accretion prevention device 10, and driving safety. Can be greatly improved.

In the above description, the case where the infrared heater 7 is used as the electric heater is shown. However, a nichrome wire, a carbon sheet heating element, a resistance metal sheet heating element, or the like can be used, and a transparent resistance thin film is used. May be. In the above description, the case where the three space portions 21A, 21B, and 21C are formed corresponding to the lamps 15 of red, yellow, and blue is shown. However, the lamps 15 of red and blue are supported. Then, two space portions 21A and 21B may be formed.

It is a front view which shows the snow accretion prevention apparatus of the signal light by one Embodiment of this invention. It is a vertical side view which shows the snow accretion prevention apparatus of the signal light of FIG. It is a vertical side view which expands and shows the principal part of the snow accretion prevention apparatus of FIG. It is a horizontal sectional view which expands and shows the snow accretion prevention apparatus of the signal lamp of FIG. It is a front view which shows the conventional snow accretion prevention apparatus of a signal light. It is a vertical side view which shows the snow accretion prevention apparatus of the signal light of FIG. It is a vertical side view which expands and shows the principal part of the snow accretion prevention apparatus of FIG.

1 Snow accretion prevention device 1
2 Metal case
3A, 3B Window frame
4A, 4B heat-resistant glass plate
5 Heating wire
6 Glass tube
7 Infrared heater
8 connection terminals
9 Lead wire
10 Snow accretion prevention device
11 Temperature sensor
12 Paint
13 Signal light
14 Food cover
15 lamp
16 Back plate
18 icicles
19 snow
20 Partition plate
21A, 21B, 21C Space
23 Earl Club
24 Electric heater wire

Claims (6)

A window frame is formed on the front and rear surfaces of a hollow flat metal case, a heat-resistant glass plate is attached to the window frame, the inside of the metal case is sealed, and the metal case is attached to a plurality of lamps in the vertical direction. Installed on the inside of the hood cover joined to the front, divided the metal case into multiple parts corresponding to the lamps of the signal lights, and installed the electric heater on the bottom side of each divided space part, located at the bottom The bottom portion side of the space portion to be expanded to the signal lamp side to form a side L-shaped space portion to substantially close the gap between the lower portion of the signal lamp, and the electric heater in the metal case An apparatus for preventing snow accretion of a signal lamp, characterized in that air is heated to a high temperature to melt snow adhering to a heat-resistant glass plate in front of a metal case. The signal light snow accretion prevention device according to claim 1, wherein an electric heater wire is joined to the inside of the hood cover to heat the hood cover. The apparatus for preventing snow accretion of a signal lamp according to claim 1, wherein a window frame corresponding to each lamp of the signal lamp is formed in a circle on the front and rear surfaces of the metal case, and a circular heat-resistant glass plate is attached thereto. 2. The signal light snow-prevention device according to claim 1, wherein the front surface of the metal case is attached to the hood cover so as to be inclined forward. The electric heater is formed of an infrared heater in which a heating wire is inserted into a glass tube, and the infrared heater is attached at a position avoiding a window frame portion of each space portion of a sealed metal case. The snow accretion prevention apparatus of the signal light of 1. 6. The signal light snow-prevention device according to claim 5, wherein the surface of the glass tube of the infrared heater is painted black.