Heating cable for snow melting and snow melting system using same

Abstract

The present invention relates to a snow-melting heating cable and a snow-melting system using the same, as a snow-melting heating cable comprising a heat-generating body, the heat-generating body comprising: a plurality of metal-coated carbon fiber wires in which a metal-coated carbon fiber bundle is wound with a first glass fiber; and a second glass fiber wound around the plurality of metal-coated carbon fiber wires, the first glass fiber is wound around the metal-coated carbon fiber bundle at a specific twist angle along the outer peripheral surface of the metal-coated carbon fiber bundle.

Description

Technical Field

[0001] The present invention relates to a heating cable for snow melting and a snow melting system using the heating cable for snow melting. Background Art

[0002] The snow melting system is a system that constructs an efficient snow removal system for vulnerable locations as a means of ensuring traffic safety in areas where traffic accidents are expected to occur, such as steep slopes of roads, entrances and exits of airport (APT) parking lots, and entrances and exits of tunnels when snow and ice form in winter. Electric heating wires or heating pipes are buried at a certain depth under the road pavement. When the road freezes due to snow or temperature differences in winter, the system automatically detects temperature and humidity and supplies power to perform snow and ice melting.

[0003] Generally speaking, when snow and ice accumulate on the road, physical removal methods such as snowplows or calcium chloride are used to prevent vehicles from slipping and further accidents. However, for the above-mentioned snow removal methods, snow removal operations must be performed immediately when snow accumulates, and if snowfall continues for a long time, operators need to be on standby to perform snow removal operations.

[0004] In addition, excessive use of snow removers will not only cause corrosion to vehicles, but will also turn into fine dust after drying and become a factor inducing environmental pollution. Moreover, calcium chloride will cause the road surface to dent and form potholes, which is also one of the main causes of road accidents. Calcium chloride not only melts snow, but also reduces the binding force of asphalt. The fragile road as described above is easily damaged by the load of vehicles.

[0005] As a snow melting system for solving the above-mentioned problems, a variety of road snow melting devices have been disclosed, and as a method as described above, Korean Registered Patent Gazette No. 10-1898727 discloses a method of transferring heat in a fluid to a road surface by burying a heat dissipation pipe under the road surface and allowing a heat source, i.e., a fluid, to flow through the heat dissipation pipe. Summary of the invention

[0006] An object of the present invention is to provide a snow-melting heating cable having excellent durability and easy heat generation control, and a snow-melting system using the snow-melting heating cable.

[0007] However, the above purpose is only exemplary, and the technical concept of the present invention is not limited thereto.

[0008] In order to achieve the above object, one aspect of the present invention relates to a snow melting heating cable, comprising a heating element, wherein the heating element comprises: a plurality of metal coated carbon fiber wires, formed by winding a metal coated carbon fiber bundle with a first glass fiber; and a second glass fiber, wound around the plurality of metal coated carbon fiber wires;

[0009] The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer circumference of the metal coated carbon fiber bundle.

[0010] In the above aspect, the angle may be 30 to 60 degrees based on the longitudinal axis of the metal-coated carbon fiber bundle.

[0011] In the one aspect, the metal coated carbon fiber wire may satisfy the following Relationship 1.

[0012] [Equation 1]

[0013] |D0-D 90 | / D0×100≤10

[0014] (In the above relational expression 1, D0 and D 90 are the diameters of the metal-coated carbon fiber wires, D0 is the fiber diameter in one direction (μm), and D 90 is the fiber diameter in the direction perpendicular to the one direction (μm).

[0015] In the above aspect, the metal-coated carbon fiber bundle may be a bundle consisting of 100 to 50,000 single filaments, and the single filaments may be carbon fibers coated with a first metal and a second metal.

[0016] As a specific example, the first metal may be nickel or copper, and the second metal may be nickel.

[0017] In the above-mentioned embodiment, the snow melting heating cable may include a heating element, a first heat-resistant resin layer, a metal braided layer, and a second heat-resistant resin layer in order from the inside. As a specific example, the first heat-resistant resin layer and the second heat-resistant resin layer may each independently include polyamide (PA), polyethylene (PE), polypropylene (PP), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PB T), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile-styrene-acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS) and polyetheretherketone (PEEK) thermoplastic resin; and any one or more selected from the rubber resins of natural rubber, ethylene-propylene-diene monomer (EPDM), styrene-butadiene, ethylene-propylene, chloroprene, hepalon (chlorosulfonated polyethylene rubber), silicone and ethylene vinyl acetate.

[0018] Another aspect of the present invention relates to a snow melting system, comprising a snow melting heating cable buried under a road.

[0019] The snow melting heating cable comprises a heating element, wherein the heating element comprises: a plurality of metal coated carbon fiber wires, formed by winding a metal coated carbon fiber bundle with a first glass fiber; and a second glass fiber, wound with the plurality of metal coated carbon fiber wires;

[0020] The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer circumference of the metal coated carbon fiber bundle.

[0021] According to the snow-melting heating cable of the present invention, a heating element is used in which a metal-coated carbon fiber bundle having its outer circumference wound with glass fiber is twisted together and then wound with glass fiber again. This allows the diameter and center point of the metal-coated carbon fiber line to be stably maintained, thereby precisely controlling the target level of heat generation, and has excellent physical properties such as durability.

[0022] In addition, the snow melting system using the snow melting heating cable can quickly remove ice on the road or prevent ice formation by releasing heat in advance, thereby improving road safety. Moreover, by using the snow melting heating cable with excellent durability, the wire is almost never broken even when subjected to pressure or stress during driving of the car, thereby continuously maintaining excellent snow melting characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1FIG. 1 is an exemplary diagram of a metal-coated carbon fiber wire according to an embodiment of the present invention.

[0024] Figure 2 1 is an infrared thermal imaging camera image of the snow melting heating cable according to the present invention.

[0025] Figure 3 as well as Figure 4 Another pattern structure of the snow melting heating cable according to the present invention is shown in the figure. DETAILED DESCRIPTION

[0026] Next, the snow melting heating cable according to the present invention and the snow melting system using the snow melting heating cable will be described in detail. The accompanying drawings introduced below are provided as examples in order to fully convey the idea of ​​the present invention to relevant practitioners. Therefore, the present invention is not limited to the accompanying drawings presented below, but can be embodied in other forms, and the accompanying drawings presented below may be exaggerated in order to clarify the idea of ​​the present invention. Unless otherwise defined, the meanings of the technical and scientific terms used at this time are the same as those generally understood by persons having general knowledge of the technical field to which the present invention belongs. In the following description and drawings, descriptions related to known functions and structures that may make the gist of the present invention unclear will be omitted.

[0027] One aspect of the present invention relates to a snow-melting heating cable, as a snow-melting heating cable including a heating element, the heating element including: a plurality of metal-coated carbon fiber strands, a metal-coated carbon fiber bundle wound with a first glass fiber; and a second glass fiber wound with the plurality of metal-coated carbon fiber strands;

[0028] The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer circumference of the metal coated carbon fiber bundle.

[0029] As described above, the snow-melting heating cable according to the present invention uses a heating element that is obtained by plying a metal-coated carbon fiber bundle whose outer circumference is wound around the metal-coated carbon fiber bundle with glass fibers and then winding it again with glass fibers, thereby stably maintaining the diameter and center point of the metal-coated carbon fiber wire and thereby precisely controlling the target level of heat generation, and has excellent physical properties such as durability.

[0030] In addition, the snow melting system using the snow melting heating cable can quickly remove ice on the road or prevent ice formation by releasing heat in advance, thereby improving road safety. Moreover, by using the snow melting heating cable with excellent durability, the wire is almost never broken even when subjected to pressure or stress during driving of the car, thereby continuously maintaining excellent snow melting characteristics.

[0031] Next, the components of the snow melting heating cable according to one embodiment of the present invention will be described in more detail.

[0032] The snow melting heating cable according to one example of the present invention may include a heating element, a first heat-resistant resin layer, a metal braided layer, and a second heat-resistant resin layer in order from the inside.

[0033] As described above, a heating element according to one example of the present invention includes: a plurality of metal-coated carbon fiber wires, a metal-coated carbon fiber bundle being wound with a first glass fiber; and a second glass fiber being wound with the plurality of metal-coated carbon fiber wires; the metal-coated carbon fiber bundle being formed by winding the outer circumference of the metal-coated carbon fiber bundle with the first glass fiber at a certain angle and a certain interval.

[0034] As a specific example, the angle may be 30 to 60° based on the longitudinal axis of the metal-coated carbon fiber bundle, preferably, 40 to 60°, and more preferably, 50 to 60°.

[0035] Within the above range, when manufacturing the snow-melting heating cable, the diameter and the center point of the metal-coated carbon fiber wire can be more stably maintained.

[0036] Preferably, the metal coated carbon fiber wire can satisfy the following relational expression 1.

[0037] [Equation 1]

[0038] |D0-D 90 | / D0×100≤10

[0039] (In the above relational expression 1, D0 and D 90 are the diameters of the metal-coated carbon fiber wires, D0 is the fiber diameter in one direction (μm), and D 90 is the fiber diameter in the direction perpendicular to the one direction (μm).

[0040] That is, the metal coated carbon fiber wire may have a concentric circle structure that stably maintains the diameter and the center point, thereby preventing the metal coated carbon fiber bundle from deviating in a specific direction and thereby precisely controlling the heat generation of the target level. 90 | / D0×100 may be less than 5, more preferably less than 3, and the lower limit may be 0. On the contrary, when the metal-coated carbon fiber wire does not have a concentric circle structure and is severely deformed, different regions of the heating cable may have different heating levels.

[0041] In addition, according to the metal-coated carbon fiber bundle of one example of the present invention, carbon fibers with metal coating formed on the outer diameter of the carbon fibers by gold plating can be used without restriction, but in order to meet the heating characteristics and mechanical strength to be produced by the present invention, it is appropriate to use carbon fibers with double metal coating formed by electroless gold plating and electrolytic gold plating. As a specific example, it can be a metal-coated carbon fiber that is electrolytically plated with nickel after electroless gold plating with nickel or copper, but it is not limited to this. Preferably, carbon fibers with double metal coating formed by electroless gold plating and electrolytic gold plating can be used, but more preferably, it can be a single nickel coating. As a specific example, it can be a metal-coated carbon fiber that is electrolytically plated with nickel after electroless gold plating with nickel or copper, and it can also be a metal-coated carbon fiber that is coated by electrolysis and electroless electrolysis using nickel alone. In addition, the thickness of the metal coating generated by the gold plating can be 50 to 800nm. Depending on the thickness of the metal coating, the metal-coated carbon fiber may present different resistances, preferably, the resistance can be 0.1 to 10Ω / m, but it is not limited to this.

[0042] The metal-coated carbon fiber bundle can be a bundle consisting of 100 to 50,000 strands of monofilament. Preferably, 1K (1,000 strands of monofilament), 3K (3,000 strands of monofilament), 6K (6,000 strands of monofilament), 12K (12,000 strands of monofilament), 48K (48,000 strands of monofilament) metal-coated carbon fiber bundles can be used. More preferably, 3K (3,000 strands of monofilament) to 6K (6,000 strands of monofilament), 12K (12,000 strands of monofilament) metal-coated carbon fiber bundles can be used.

[0043] As the name suggests, the first glass fiber according to one example of the present invention is a thin and long material obtained by spinning glass into fibers. The diameter of the first glass fiber may be 1 to 20 μm, preferably 3 to 15 μm, but is not limited thereto.

[0044] In addition, the first glass fiber may be one strand or two or more strands, preferably, 3 to 20 strands of glass fiber may be used, which helps to more stably maintain the diameter and center point of the metal coated carbon fiber filament when manufacturing the heating cable.

[0045] The metal coated carbon fiber bundle as described above can be manufactured by a) preparing the metal coated carbon fiber bundle; and b) winding the first glass fiber at a specific twist angle along the outer circumference of the metal coated carbon fiber bundle.

[0046] First, a) a step of preparing a metal-coated carbon fiber bundle may be performed.

[0047] As described above, the metal-coated carbon fiber bundle according to one example of the present invention can use carbon fibers having a metal coating formed on the outer diameter of the carbon fibers through a gold plating process without restriction. However, in order to meet the heating characteristics and mechanical strength to be achieved by the present invention, it is preferable to use carbon fibers having a double metal coating formed by electroless gold plating and electrolytic gold plating.

[0048] As a specific example, the step a) may include: a-1) performing electroless gold plating on carbon fiber using a first metal; and a-2) performing electrolytic gold plating on the electroless gold-plated carbon fiber using a second metal.

[0049] The types of the first metal and the second metal may be the same or different from each other. Preferably, the first metal may be nickel or copper, and the second metal may be nickel.

[0050] The electroless and electrolytic processes of the present invention may be performed by the method disclosed in Korean Patent Registration No. 10-1427309, but are not limited thereto.

[0051] The step a-1) can be performed by passing the carbon fiber through an electroless gold plating solution comprising pure water, a first metal salt, a complexing agent, a reducing agent, a stabilizer and a pH adjuster, and the step a-2) is performed continuously after the step a-1) and can be performed by utilizing a second metal salt and a pH buffer and loading a constant voltage (CV) of 5 to 15 V, but is not limited to the method.

[0052] The carbon fiber may be pretreated by a pretreatment process including (i) passing the carbon fiber through an aqueous solution containing a surfactant, an organic solvent and a non-ionic surfactant to degrease and soften the carbon fiber; (ii) passing the product of step (i), i.e. the carbon fiber, through an aqueous solution containing sodium sulfite (NaHSO3), sulfuric acid (H2SO4), ammonium persulfate ((NH4)2S2O8) and pure water to perform an etching process for neutralization, cleaning and conditioning; (iii) passing the product of step (ii), i.e. the carbon fiber, through an aqueous solution of PdCl2 to perform a sensitizing process; and (iv) passing the product of step (iii), i.e. the carbon fiber, through an aqueous solution of sulfuric acid (H2SO4) to perform an activating process; but the present invention is not limited thereto.

[0053] The thickness of the metal coating generated by the gold plating may be 50 to 800 nm, preferably 100 to 500 nm.

[0054] According to the thickness of the metal coating, the metal coated carbon fiber may present different resistances. Preferably, the resistance may be 0.1 to 10 Ω / m, but is not limited thereto.

[0055] As described above, after the metal coated carbon fiber bundle is prepared, the step of b) winding the first glass fiber at a specific twist angle along the outer circumference of the metal coated carbon fiber bundle may be performed.

[0056] At this time, the angle in step b) can be 30 to 60° based on the longitudinal axis of the metal-coated carbon fiber bundle, preferably 40 to 60°, more preferably 50 to 60°.

[0057] In addition, the interval may be the distance between the centers of the first glass fibers and the first glass fibers disposed at intervals, and as a specific example, may be 50 to 300 μm. Within the above range, the diameter and the center point of the metal coated carbon fiber wire may be more stably maintained when manufacturing the heating cable.

[0058] In addition, the step b) may be performed by applying a tension of 5 to 10 N / tex to the metal coated carbon fiber bundle.

[0059] Within the above range, the metal coated carbon fiber bundle will not be bent and deformed during step b), thereby preventing the conductor from being damaged, and the diameter and center point of the metal coated carbon fiber line can be more stably maintained. On the contrary, when the tension is less than 5 N / t ex, the center point of the heating wire may deviate excessively from the concentric point, and when the tension exceeds 10 N / t ex, the friction between the metal coated carbon fiber bundle and the glass fiber may cause fiber breakage (fine wire breakage) of the metal coated carbon fiber bundle or damage to the metal coating, thereby increasing the conductor resistance.

[0060] In addition, in the step b), the first glass fiber may be wound at a rotation speed of 50 to 300 cycles / min, and preferably, the first glass fiber may be wound at a rotation speed of 100 to 200 cycles / min.

[0061] Within the above range, the metal coated carbon fiber bundle will not be damaged.

[0062] The metal-coated carbon fiber wire manufactured in the above-described manner can be wound again with the second glass fiber after the plurality of strands are combined. That is, the second glass fiber, like the first glass fiber, can be wound around the outer peripheral surface of the plurality of metal-coated carbon fiber wires at a specific angle and a specific interval. As a specific example, the angle can be 30 to 60° based on the longitudinal axis of the metal-coated carbon fiber wire, preferably 40 to 60°, and more preferably 50 to 60°.

[0063] In addition, the interval may be the distance between the centers of the second glass fibers and the second glass fibers disposed at intervals, and as a specific example, may be 50 to 300 μm. Within the above range, heat generation control can be easily achieved when manufacturing the heating cable.

[0064] At this time, the plurality of metal coated carbon fiber strands may be more than two strands. Specifically, for example, 2 to 10 strands of metal coated carbon fiber strands may be twisted together. More preferably, 4 to 8 strands of metal coated carbon fiber strands may be twisted together.

[0065] In addition, the second glass fiber according to one example of the present invention may be the same as the first glass fiber, and the diameter of the second glass fiber may be 1 to 20 μm, preferably 3 to 15 μm / m, but is not limited thereto.

[0066] In addition, the second glass fiber may be one strand or two or more strands. Preferably, 3 to 20 strands of the second glass fiber are used.

[0067] Next, according to one example of the present invention, the first heat-resistant resin layer and the second heat-resistant resin layer can use materials with insulation and heat resistance without special restrictions. As a specific example, the first heat-resistant resin layer and the second heat-resistant resin layer can each independently include polyamide (PA), polyethylene (PE), polypropylene (PP), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polyvinyl chloride (PVC ... ), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile-styrene-acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS) and polyetheretherketone (PEEK) and other thermoplastic resins; and rubber resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene-butadiene, ethylene-propylene, chloroprene, hepalon (chlorosulfonated polyethylene rubber), silicone and ethylene vinyl acetate; any one or more selected from the following.

[0068] The metal braided layer according to one embodiment of the present invention is used to reinforce the shear force of the metal-coated carbon fiber and protect the conductor from external impact. It can be braided using metal wires such as copper, stainless steel or tin-plated gold wire.

[0069] The snow-melting heating cable as described above may include: A) a step of manufacturing a heating element; B) a step of coating the heating element with a first heat-resistant resin through a first sheathing process to thereby manufacture a cable wire; C) a step of braiding the cable wire into a metal wire through a braiding process; and D) a step of coating the braided cable wire with a second heat-resistant resin through a second sheathing process to thereby manufacture a snow-melting heating cable.

[0070] If necessary, when the required resistance per unit length cannot be produced, a twisting process may be performed to twist two or more insulated cable conductors together to produce a cable bundle.

[0071] Another aspect of the present invention relates to a snow melting system including a snow melting heating cable buried under a road.

[0072] The snow melting heating cable comprises a heating element, and the heating element comprises: a plurality of metal coated carbon fiber wires, a metal coated carbon fiber bundle is wound with a first glass fiber; and a second glass fiber is wound with the plurality of metal coated carbon fiber wires;

[0073] The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer peripheral surface of the metal coated carbon fiber bundle.

[0074] As described above, the snow melting system using the snow melting heating cable can quickly remove ice on the road or prevent ice formation by releasing heat in advance, thereby improving road safety. Moreover, by using a snow melting heating cable with excellent durability, the cable will hardly break even when subjected to pressure or stress from the heating cable during vehicle travel, thereby continuously maintaining excellent snow melting characteristics.

[0075] At this time, the snow melting heating cable is the same as the above-mentioned content, so the repeated description will be omitted.

[0076] In addition, the snow melting system may further include: a power supply unit for supplying power to the heating cable; a power control unit for controlling the supplied power; a heating control unit for controlling the degree of heating; and a sensor unit for sensing the degree of heating.

[0077] Next, the snow melting heating cable according to the present invention and the snow melting system using the snow melting heating cable will be described in more detail through embodiments. However, the following embodiments are only a reference for describing the present invention in detail, and the present invention is not limited thereto, but can be implemented in various forms.

[0078] In addition, unless otherwise defined, all technical terms and scientific terms have the same meaning as those generally understood by ordinary practitioners in the field to which the present invention belongs. The terms used in the description of this application are only used to effectively describe specific embodiments and are not intended to limit the present invention. In addition, the unit of additives not clearly stated in this specification may be weight %.

[0079] [Manufacturing Example 1]

[0080] Using 3000 (3K) strands of carbon fiber, a nickel-coated carbon fiber bundle (nickel coating thickness: 100 nm, MCF) was manufactured according to the metal-plated carbon fiber manufacturing method according to Registered Patent No. 10-1427309.

[0081] While applying a tension of 1N / tex to the nickel-coated carbon fiber bundle, a first glass fiber (20 strands, 5μm in diameter) is wound around the outer peripheral surface of the nickel-coated carbon fiber bundle (MCF) at a rotation speed of 100 cycles / minute. At this time, the metal-coated carbon fiber wire is produced by adjusting the state of being twisted 30° based on the longitudinal axis of the metal-coated carbon fiber bundle.

[0082] [Manufacturing Examples 2 to 7]

[0083] As shown in Table 1 below, except for adjusting the angle of the first glass fiber, all processes were performed in the same manner as in Example 1 to produce a metal-coated carbon fiber yarn.

[0084] [Manufacturing Example 8 to Manufacturing Example 11]

[0085] As shown in Table 1 below, all processes were performed in the same manner as in Example 1, except that the tension applied to the nickel-coated carbon fiber bundle was adjusted, to produce a metal-coated carbon fiber wire.

[0086] [Comparative Manufacturing Example 1]

[0087] After preparing a nickel-coated carbon fiber bundle (nickel coating thickness: 100 nm) in the same manner as in Example 1, a metal-coated carbon fiber wire was manufactured without winding the first glass fiber.

[0088]

Table 1

[0089] Number of strands Angle (°) Tension (N / tex) Production Example 1 3K 30 5 Production Example 2 3K 40 5 Production Example 3 3K 50 5 Production Example 4 3K 53 5 Production Example 5 3K 57 5 Production Example 6 3K 60 5 Production Example 7 3K 65 5 Production Example 8 3K 57 1 Production Example 9 3K 57 3 Production Example 10 3K 57 10 Production Example 11 3K 57 15 Comparative Manufacturing Example 1 3K - -

[0090] The metal-coated carbon fiber yarns prepared in Examples 1 to 11 and Comparative Example 1 were coated with polyamide 6 (PA6) resin (density 1.14 g / cm 3 , melting point 220℃, tensile strength 83MPa, Izod impact strength 7.5Kgf·cm / cm, heat deformation temperature 65℃) and then braided copper wire on its outer diameter, and then coated with polyamide 6 (PA6) resin again by extrusion molding to produce a heating cable test piece. The properties of the test piece produced in the above manner were evaluated according to the following method. 1) Diameter measurement: The diameter (D 90 , μm) and the fiber diameter in the perpendicular direction (D 90 , μm) and calculated the difference rate (%) according to equation 1. The results are shown in Table 2 below.

[0091] 2) Electrical resistance (Ω / m): The electrical resistance (Ω / m) per meter of the metal-coated carbon fiber for the heating cable was measured. The results are shown in Table 2 below.

[0092]

Table 2

[0093]

[0094] It can be confirmed that when the first glass fiber is wound around the metal coated carbon fiber bundle according to the present invention, the center point is stable, so the difference in diameter in two directions perpendicular to each other is smaller than that in Comparative Example 1, and the resistance is also reduced. However, in Example 11, since the tension applied to the metal coated carbon fiber bundle is too large, the fiber breakage (fine wire breakage) of the metal coated carbon fiber bundle or the metal coating is damaged, resulting in a problem that the resistance is greater than that of Comparative Example 1.

[0095] [Examples 1 to 11 and Comparative Example 1]

[0096] After plying 6 strands of the metal-coated carbon fiber wires manufactured in Manufacturing Examples 1 to 11 and Comparative Manufacturing Example 1, a second glass fiber (20 strands, 5 μm in diameter) was wound at a rotation speed of 100 cycles / minute while applying a tension of 1 N / tex. At this time, the heating element was manufactured by adjusting the state in which the metal-coated carbon fiber bundle was twisted 57° based on the longitudinal axis.

[0097] Next, the heat generating element was coated with silicone resin (Shin-Etsu KR 242A) by extrusion molding, and copper wires were braided around the outer diameter thereof. Then, Teflon resin was coated again by extrusion molding, thereby manufacturing a snow-melting heating cable test piece.

[0098] The manufactured snow melting heating cable test piece is Figure 1 After folding into a rectangular structure in the manner shown, its resistance and heating temperature were measured. When measuring the heating temperature, a 12V DC was loaded and the highest point temperature was measured using an infrared (IR) camera in the bending section, and the average temperature was calculated. The test was performed once for 40 hours, and the average value was calculated after repeating it 5 times. As a result, the average resistance of the snow melting heating cable test piece was 0.4Ω, and the average heating temperature was 142.5℃.

[0099] In addition, if Figure 2 as well as Figure 3 As shown in FIG. 1 , the resistance of the snow melting heating cable test piece was measured after the pattern structure was changed. The result was: Figure 2 The structure in the test piece measured 0.54Ω when the heating wire length was 3500mm, while Figure 3 The structure in the figure measured 0.7Ω when the heating wire length was 4600mm.

[0100] In the above content, the present invention is explained through specific matters and limited embodiments, but this is only to help a more comprehensive understanding of the present invention. The present invention is not limited to the embodiments, and a person with general knowledge in the field of the present invention can make various modifications and deformations based on the description.

[0101] Therefore, the concept of the present invention is not limited to the illustrated embodiments, but only to the attached claims, and all modifications that are equal or equivalent to the claims should be interpreted as being included in the scope of the concept of the present invention.

Claims

1. A heating cable for snow melting, characterized in that: Including heating element, The heating element comprises: a plurality of metal-coated carbon fiber wires, which are formed by winding a metal-coated carbon fiber bundle with a first glass fiber; and a second glass fiber, which is wound around the plurality of metal-coated carbon fiber wires; The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer circumference of the metal coated carbon fiber bundle.

2. The snow melting heating cable according to claim 1, characterized in that: The angle is 30 to 60 degrees based on the longitudinal axis of the metal-coated carbon fiber bundle.

3. The snow melting heating cable according to claim 1, characterized in that: The metal coated carbon fiber wire satisfies the following relation 1: [Equation 1] |D0-D 90 | / D0×100≤10 In the above relational expression 1, D0 and D 90 are the diameters of the metal-coated carbon fiber wires, D0 is the fiber diameter in one direction (μm), and D 90 is the fiber diameter (μm) in the direction perpendicular to the one direction.

4. The snow melting heating cable according to claim 1, characterized in that: The metal-coated carbon fiber bundle is a bundle consisting of 100 to 50,000 single filaments.

5. The snow melting heating cable according to claim 4, characterized in that: The monofilament is formed by coating a carbon fiber with a first metal and a second metal.

6. The snow melting heating cable according to claim 5, characterized in that: The first metal is nickel or copper, and the second metal is nickel.

7. The snow melting heating cable according to claim 1, characterized in that: The snow-melting heating cable includes a heating element, a first heat-resistant resin layer, a metal braided layer and a second heat-resistant resin layer in order from the inside.

8. The snow melting heating cable according to claim 7, characterized in that: The first heat-resistant resin layer and the second heat-resistant resin layer each independently include thermoplastic resins selected from polyamide (PA), polyethylene (PE), polypropylene (PP), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer resin (SAN), acrylonitrile-styrene-acrylate copolymer resin (ASA), polyphenylene ether (PPE), polyphenylene sulfide (PPS) and polyetheretherketone (PEEK); and any one or more selected from rubber-based resins such as natural rubber, ethylene-propylene-diene monomer (EPDM), styrene-butadiene, ethylene-propylene, chloroprene, hepalon, silicone and ethylene vinyl acetate.

9. A snow melting system, characterized in that: Including heating cables buried under the road for melting snow, The snow melting heating cable comprises a heating element, wherein the heating element comprises: a plurality of metal coated carbon fiber wires, formed by winding a metal coated carbon fiber bundle with a first glass fiber; and a second glass fiber, wound with the plurality of metal coated carbon fiber wires; The first glass fiber is wound around the metal coated carbon fiber bundle at a specific twisting angle along the outer circumference of the metal coated carbon fiber bundle.

10. The snow melting system according to claim 9, characterized in that: The angle is 30 to 60 degrees based on the longitudinal axis of the metal-coated carbon fiber bundle.

11. The snow melting system according to claim 9, characterized in that: The metal coated carbon fiber wire satisfies the following relation 1: [Equation 1] |D0-D 90 | / D0×100≤10 In the above relational expression 1, D0 and D 90 are the diameters of the metal-coated carbon fiber wires, D0 is the fiber diameter in one direction (μm), and D 90 is the fiber diameter (μm) in the direction perpendicular to the one direction.

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