JP2003096740A - Snow melting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a snow melting system in which a construction period can be shortened and cost is reduced. SOLUTION: The snow melting system has a conductive mixed body, which is laid on a section to be snow-melted in a road or the like and in which powdered carbon is mixed with cement, and a power device being connected to the conductive mixed body and making a current flow through the mixed body for heat-generating the mixed body by Joule heat. The installation of a heating element and the pavement of the road are completed simultaneously by laying the conductive mixed body in which powdered carbon is mixed with cement on the road. That is, since the conductive mixed body functions as the heating element and pavement in combination, the construction period is shortened and the cost is reduced. Heat-generating Joule heat and the quantity of the current can be adjusted freely by adjusting the mixing ratio of powdered carbon.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a snow melting system for melting snow accumulated on a road or the like.

[0002]

2. Description of the Related Art In a snowfall area, as a means of protecting roads covered with snow (concrete pavement, etc.) from freezing,
Snow melting agents such as sodium chloride are sprayed on the road surface. However, if the snow-melting agent is sprayed on the concrete surface, chloride ions contained in the snow-melting agent may permeate from the outside to the inside to corrode the reinforcing bar and deteriorate the concrete. Corrosion also occurs in automobiles running on roads.

In order to avoid such salt damage, a snow melting system has been proposed in which a net having heating wires meanderingly attached is laid on a road and paved on the net (Japanese Patent Laid-Open No. 9-78517). . According to this snow melting system, heat can be generated by passing an electric current through the carbon heating wire, and the snow accumulated on the road can be melted without salt damage.

[0004]

However, in such a snow-melting system, it is necessary to lay a net with a heating wire on the road and then pave it. A process of meandering and attaching and a process of laying the net with the heating element on the road are required, which causes a long construction period and an increase in cost.

An object of the present invention, which was devised in consideration of the above circumstances, is to provide a snow melting system capable of shortening the construction period and reducing the cost.

[0006]

In order to achieve the above object, the present invention provides a conductive mixture which is laid on a portion of a road or the like where snow is to be melted and which is prepared by mixing powder carbon with cement, and the conductive mixture. And a power supply device that is connected and supplies an electric current to the mixture to generate heat by Joule heat.

According to the present invention, the conductive mixture of powder carbon mixed with cement, which is laid on the road, serves both as the heating element and the pavement, so that the construction period and cost can be shortened. You can That is, by laying the conductive mixture on a road, the installation of the heating element and the paving of the road are completed at the same time. Further, by adjusting the mixing ratio of the powdered carbon, it is possible to freely adjust the Joule heat and the amount of current that generate heat.

In addition, a plurality of the above-mentioned conductive mixtures are laid at predetermined intervals in the longitudinal direction of a portion such as a road where snow is to be melted. You may connect the electrode of the said power supply device to the both ends of the sex mixture in the width direction.

In this case, since the electric resistance of each conductive mixture becomes substantially constant, a substantially constant current will flow,
Each heat generation temperature becomes substantially constant. Therefore, the accumulated snow can be melted almost uniformly without spots.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view of a concrete road provided with the snow melting system according to this embodiment, and FIG. 2 is a perspective plan view of the road.

As shown in FIG. 1, a conductive mixture 2 in which powder carbon is mixed with cement is laid on a concrete base 1 of a road where snow and ice should be melted by spraying or driving.

As the conductive mixture 2, not only a paste prepared by mixing cement and powdered carbon with water, but also mortar mixed with sand, concrete mixed with gravel, etc. are appropriately used according to the required strength. To be In this embodiment, cement having an average particle size of 13 μm and carbon having an average particle size of 4 μm is used, but the present invention is not limited to these particle sizes.

As shown in FIG. 2, a plurality of conductive mixtures 2 are laid in a rectangular shape with a predetermined insulation interval (several centimeters) in the longitudinal direction of the road 3. In the present embodiment, the length of each conductive mixture 2 in the longitudinal direction of the road is about several meters, and the thickness is set to about 40 mm in consideration of wear and weight loss, but the number is not limited to these values. Not something.

A non-conductor 4 is interposed between the conductive mixtures 2 in order to prevent a short circuit. As the non-conductor 4, paste, mortar, concrete, rubber, or the like, which is not mixed with powdered carbon, is appropriately used according to the required strength. The heights of the non-conductor 4 and the conductive mixture 2 are flush with each other.

A power supply device 5 is connected to each conductive mixture 2 for supplying an electric current to the mixture 2 in order to heat the mixture 2 by Joule heat. The power supply device 5 includes electrode wires 6 connected to both ends of each conductive mixture 2 in the width direction of the road, and left and right in the width direction of the road 3 connected to each electrode line 6 along the longitudinal direction of the road 3. Assembly line 7 laid each
And a DC power source 9 connected to the assembly line 7 via a switch 8 to form a parallel circuit for each conductive mixture 2.

The operation of this embodiment having the above configuration will be described.

When snow 11 or ice on the conductive mixture 2 is melted or melted, the switch 8 of the power supply device 5 is turned on. Then, an electric current flows through each conductive mixture 2, Joule heat is generated by the electric resistance of the conductive mixture 2 (containing cement and powder carbon), and snow or ice on the conductive mixture 2 melts. Melted ice.

Here, since the electrically conductive mixture 2 laid on the road 3 in which cement is mixed with powdered carbon serves both as a heating element and pavement, the construction period can be shortened and the cost can be reduced. it can. That is, by laying the conductive mixture 2 on the road 3, the heating element is installed and the road 3 is installed.
Since the paving is completed at the same time, the construction period can be shortened and the cost can be reduced.

Since the conductive mixture 2 is a cement type hardened body, it has good adhesion to the concrete base 1.
In addition, the conductive mixture 2 can be manufactured by mixing powder carbon with general cement, so that not only the material cost is low, but also construction (spraying, etc.) can be performed in the same manner as ordinary mortar and the like, so construction costs can also be suppressed. . In addition, the conductive mixture 2
Even if the switch 8 of the power supply device 5 is not turned on, since the mixed powder carbon is black, it is easy to absorb solar heat and the snow melting effect is high.

In the illustrated example, as shown in FIG. 2, a plurality of conductive mixtures 2 are laid at predetermined intervals in the longitudinal direction of the road, and a non-conductor 4 is provided between the conductive mixtures 2. Since the electrode wires 6 of the power supply device 5 are connected to both ends of each conductive mixture 2 in the width direction and the power source 9 is connected in parallel to each conductive mixture 2, each conductive mixture is formed. Not only the same voltage is supplied to the body 2, but the electric resistance of each conductive mixture 2 becomes substantially constant.

That is, since the width of the road 3 is constant in each conductive mixture 2, the lengths in the width direction are equal, and if the lengths in the longitudinal direction of the road 3 are equal as shown in the figure, The volumes become equal and the electric resistance becomes substantially constant. Therefore, a substantially constant current flows through each conductive mixture 2, and the heat generation temperature due to Joule heat becomes substantially constant. Therefore, the accumulated snow and ice can be melted almost uniformly without spots.

The amount of heat generated can also be adjusted by adjusting the power supply voltage, and can also be adjusted by adjusting the mixing ratio of the powder carbon of the conductive mixture 2. In Figure 3,
When changing the weight ratio of carbon and cement,
The relationship (experimental value) between the voltage of the power supply 9 and the current value flowing through the conductive mixture 2 (current value of the ammeter 10 shown in FIG. 1) is shown.

As shown in the drawing, "carbon 0 wt%, cement 100 wt%", "carbon 10 wt%, cement 90"
When "Wt%", almost no current flows even if the voltage is increased,
An electric current is flowing at a mixing ratio of "carbon 30 wt%, cement 70 wt%" or more. FIG. 4 is a diagram showing the resistivity of the conductive mixture 2 at each mixing ratio.

Here, if the resistance of the conductive mixture 2 is so large that almost no current flows even when a voltage is applied, Joule heat will not be generated, and conversely, if the resistance is too small, the amount of heat generated by Joule heat will be small. Therefore, both are unsuitable for snow melting and ice melting systems. If the carbon content is too high,
Rigidity (strength / durability) of a running car against tires
Is decreased, which is not preferable.

Therefore, according to FIGS. 3 and 4, it is considered appropriate that the mixing ratio of the conductive mixture 2 is 25 to 50 wt% of carbon and 75 to 50 wt% of cement.

The power supply 9 in FIGS. 1 and 2 is
Not limited to direct current, alternating current may be used. This is because Joule heat can be generated in the conductive mixture even with an AC power source. Further, a pavement for insulation / protection may be further provided on the conductive mixture 2 and the non-conductor 4.

Further, the snow melting system according to the present embodiment is
In addition to being applied to concrete roads in snowy and cold regions in general, it is particularly effective to be applied to roads on bridges where there is a risk of freezing. It is also applied to bus stops, parking lots, and toll gates on toll roads. Further, the structure may be applied not only to roads but also to roofs of buildings such as water storage tanks.

[0029]

As described above, according to the snow melting system of the present invention, the construction period can be shortened and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a concrete road including a snow melting system according to this embodiment.

FIG. 2 is a perspective plan view of the road.

FIG. 3 is an explanatory diagram showing a power supply voltage and a current value at each mixing ratio of the conductive mixture.

FIG. 4 is an explanatory diagram showing the resistivity of the conductive mixture at each mixing ratio.

[Explanation of symbols]

2 Conductive mixture 3 roads 4 non-conductor 5 power supply 6 electrode wire

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinya Ikeya             Stone, Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa             Kawashima Harima Heavy Industries Co., Ltd. Machinery and plant opening             In the departure center F-term (reference) 2D026 CL02                 2D051 GA01 GC02 GC06

Claims (2)

[Claims] 1. A conductive mixture which is laid on a portion such as a road where snow is to be melted, and is mixed with powdered carbon in cement, and the mixture is connected to the conductive mixture to heat the mixture by Joule heat. A snow-melting system, comprising: 2. A plurality of the above-mentioned electrically conductive mixtures are laid at predetermined intervals in the longitudinal direction of a portion such as a road where snow is to be melted, and a non-conductor is provided between each of the electrically conductive mixtures, and each electrically conductive material is provided. The snow melting system according to claim 1, wherein electrodes of the power supply device are connected to both ends in the width direction of the sex mixture.