JPH10321356A - Self-control type cord heater and device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a self-control type cord heater with high safety and high reliability, capable of simply applying to various devices by forming a self control type heater in a flexible cord shape. SOLUTION: The device comprises a heating wire 2, a reinforcing wire 3, a core wire 6, and a cover 7, and the heating wire 2 has physical properties changing specific resistance value according to temperature change and self controlling flowing current value. A stranded wire of the heating wire 2 and the reinforcing wire 3 is protected with an inner layer 7A made of glass or the like, and its outer circumference is wrapped with an outer layer made of a stainless steel braid or the like. When ambient temperature is low in the current passing initial stage, since the specific resistance value of the heating wire 2 is small and control current value is large, the surface temperature of a heater is quickly raised. When the surface temperature of the heater becomes high, the control current value is decreased and stays in almost the constant value, and the surface temperature of the heater also becomes almost constant. Since a self control type cord heater is flexible, it can simply be wired even in a curved place or in a non-flat place, and can safely be used under environment having large difference in temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated heater using a self-controlling resistance wire, and more particularly to a heating device having a flexible cord shape to prevent snow melting, freeze prevention, frost prevention and energy saving. The present invention relates to a self-control type code heater which can be easily applied to various devices such as the above, and is suitable for enhancing safety and reliability, and an application device thereof.

[0002]

2. Description of the Related Art A conventional cord heater includes a resistance wire 10 covered with an insulator 100 as shown in FIG.
1 and a reinforcing conductor 104 covered with a reinforcing conductor insulator 102 and the outer periphery thereof is protected by a protective layer 103 made of glass. The reinforcing wires 104 are alternately arranged, and the resistance wire 101 and the reinforcing wire 104 are stranded. It is configured so as to be enclosed at 105. The resistance wire 101 is formed of a material having a property that the specific resistance value decreases as the temperature rises. In general, the heating value increases as the current value increases. That is, it is not a self-control type heating wire that performs control to change its own current value as a result of a change in the specific resistance value due to a temperature change. Therefore, for example, a controller that controls the current based on the temperature information based on the room temperature or the outside air temperature is required. For example, in the case of a snow melting / freezing prevention device, when current control cannot be performed due to a controller failure, abnormal heat generation occurs, and an unexpected situation may occur. Safety measures had to be taken for that. Especially in summer, when it is not necessary to prevent snow melting and freezing, the equipment is turned off so that it does not operate completely. The member is brought to an abnormally high temperature state due to the heat of summer and the heat of the cord heater, causing the member to be deformed or, in some cases, unusable deformation. Also, depending on the material of the member, an ignition phenomenon may occur, resulting in an extremely dangerous state. SUMMARY OF THE INVENTION An object of the present invention is to provide a self-controlling type cord heater which can be easily applied to various devices by a flexible cord-like self-controlling type heater, and which can obtain high safety and reliability. It is in. Another object is to provide an application device using a self-control type code heater.

[0003]

According to a first aspect of the present invention, there is provided a self-controlling type cord heater which controls a current by utilizing a change in a specific resistance value caused by a temperature change. It consists of an insulator covering the heating wire and a covering surrounding the insulator. The self-controlling type code heater according to claim 2 is a heating wire for controlling its own current by utilizing a change in a specific resistance value due to a temperature change, an insulator covering the heating wire, and a heating device coated with the insulator. It consists of a core wire arranged in the direction in which the wire extends, a heating wire covered with an insulator, and a covering body surrounding the core wire.

Another invention related to the invention of claim 2 is characterized by the following constitutions alone or in combination. (1) A heating wire covered with an insulator is wound around a core wire. (2) A plurality of heating wires covered with an insulator are arranged around the core wire. (3) The cover is a metal knit. (4) The cover comprises an inner protective layer and a metal knit covering the protective layer.

[0005] The invention using the cord heater is
The following device has features. (1) A snow melting device used as a heating element for melting snow. (2) An antifreezing device used as a heating element for preventing freezing. (3) A frost prevention device used as a heating element for preventing frost. (4) A heating device used as a heating element for heating. (5) A carport disposed on the roof aggregate as a heating element for melting snow. (6) A drainage channel provided in the drainage pipe as a heating element for preventing freezing. (7) A heater mat placed inside a rubber mat.

[0006]

According to the constitutions of claims 1 to 6,
When the ambient temperature in the initial stage of energization is low, since the specific resistance value of the heating wire is small, the control current value increases and the heater surface temperature rises rapidly. As the surface temperature of the heater increases, the control current value decreases and settles to a substantially constant value. At this time, the heater surface temperature is also substantially constant. The flexibility of the self-regulating cord heater allows it to be easily wired in a bent or uneven place, and can be used safely even in environments with large differences in temperature. In addition, by inserting the core wire into the cord heater, the cord heater itself is not disconnected even if it is pulled or bent, so that the assembling work and the like can be easily performed. According to the configuration of the seventh to thirteenth aspects, high safety and reliability can be obtained by using the self-control type cord heater for the snow melting device, the anti-freezing device, the underfloor heating device, and the like.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a self-control type code heater. FIG. 2 shows an AA cross section. The cord heater 1 includes a heating wire 2, a reinforcing conductor 3, a core wire 6, and a cover 7 (an inner layer 7A and an outer layer 7B). The resistor forming the heating wire 2 is made of an alloy of nickel and iron, and has a physical property in which a specific resistance value changes according to a temperature change and a current is self-controlled. The heating wire 2 is formed of a stranded wire, and has an example of a resistance value of 6.95 ohm / m. The heating wire 2 is covered with a resistance wire insulator 3 such as heat-resistant silicon rubber.

[0008] The reinforcing conductor 4 is composed of a stranded wire having a rated voltage of 200 V and 10 A, and is covered with a reinforcing conductor insulator 5.
The heating wire 2 and the reinforcing wire 4 have a four-wire structure in which two heating wires 2 and the reinforcing wire 4 are alternately arranged around a core wire 6 such as a piano wire, and the whole is formed as a stranded wire. .
The stranded wire of the heating wire 2 and the reinforcing conductor 3 is protected by an inner layer 7A of a glass braid, and its outer periphery is wrapped by an outer layer 7B of a braided shield made of stainless steel or the like.

FIG. 3 is a sectional view of a cord heater having a three-wire structure. The cord heater 1 has a three-wire structure including two heating wires 2 and one reinforcing conductor 4, and as shown in the drawing, two heating wires 2, one reinforcing conductor 3, a core wire 6, and a covering 8 (inner layer 8A). ,
It is composed of a middle layer 8B and an outer layer 8C), and is entirely formed into a stranded wire. Heating wire, reinforcing wire, and core wire are 4
Similar to the line structure. The coating 8 is composed of a mirror mirror for the inner layer 8A, a braided shield for the middle layer 8B, and a glass braid for the outer layer 8C. FIG. 4 shows a structure in which a glass core is used as the core wire and the heating wire 2 is wound around the glass core 6A.
When the specific resistance value of the resistance wire 1 is high, since a single wire is used, the strength is increased by the glass core 6A.

Next, a heater device using the above-described code heater will be described. FIG. 5 shows the basic configuration of the heater device. One end of the heating wire 2 is electrically terminated and covered with an aluminum tube terminal cap 9. When wiring the cord heater 1, for example, the cord heater 1 is connected as shown in FIG.
When the wire is drawn into the pipeline 10 shown in FIG. 1, a pull-in fitting 11 for connecting the core wire 6 to a cord or wire for the pull-in operation is attached. The other end of the heating wire 2 is connected to the thermobox 12. The thermobox 12 is provided with an energizing lamp 13 for notifying the energization to the heating wire 2, a power lamp 14 for notifying ON / OFF of the power supply, and a thermostat 15. A mounting hole 16 is provided so as to be installed at an appropriate place. Is provided. The lead wire 17 connected to the thermobox 12 is a plug 1 for connecting to a power supply.
8 is connected. This plug 18 is provided with a ground terminal 19.

The temperature characteristics of the self-control type code heater will be described. The code heater 1 was disposed inside a pipe 10 vertically piped, and the temperatures at four points shown in FIG. 6 were measured. The measurement conditions were as follows: the cord heater 1 was 6 m in length, the pipe was 100 mm in diameter, 4 m in length, the room temperature was O ° C, and the measurement was in a dry state. FIG. 7 shows the result. FIG. 7A shows the relationship between the heater surface temperature and time when the lower part of the pipeline is not sealed. If the ambient temperature at the beginning of energization is low, the specific resistance value of the heating wire is small, that is, the control current value is large and the heater current is large. The surface temperature rises and heats the inside of the pipeline. The control current value changes slightly according to the temperature rise inside the pipeline, and settles to a substantially constant control current value in about one hour. At this time, the heater surface temperature is also substantially constant, and the four locations inside the pipeline are maintained at different predetermined temperatures (about 50 to 80 ° C.).
The temperature distribution becomes lower in this order, the position near the upper and lower open ends is lower, and the middle part is higher.

FIG. 7B shows the relationship between the heater surface temperature and the time when the lower portion is closed. The control current value rapidly decreases from about 2 hours after the energization, and almost 8 hours. It is almost constant at about the same level. At this time, the surface temperature of the heater becomes almost constant,
Predetermined temperature (approximately 70-100 ° C) at each location
Is maintained. Since the lower part of the conduit is sealed, it is easy to keep warm air inside and the surface temperature of the heater increases. That is, in the structure in which the lower part of the pipeline is sealed, the temperature in the pipeline is kept higher than that in the open-bottom type, so that freezing can be efficiently prevented.

Next, an embodiment using a code heater will be described. FIG. 7 shows an embodiment applied to a snow melting / freezing prevention device. The drainage facility of the building 20 is provided with a snow stopper 22 near the lower end of the inclined roof 21, and the water collected in the snow stopper 22 is temporarily stored in a drainage basin 24 through a pipe 23, and then flows to the sewer. The cord heater 1 is disposed inside the pipe 23, and the tip of the cord heater 1 is disposed at a drainage basin 24.
Is growing. The thermobox 12 is fixed to the building 20. In the case of the building 20 shown in FIG. 9, a flat roof (land roof)
The cord heater 1 is provided in the pipe 21 between the water collecting part 25 and the drainage basin 24 of the flat roof 21A.

According to such a configuration, when the plug 18 is connected to a power source and energized, the inside of the pipe 23 is warmed by the heat generated by the cord heater 1, and the warm air rises and the snow at the snow stopper 22 on the roof is increased. Dissolve. Particularly in the daytime, snow melting by the solar heat is actively performed, and the combined use of a cord heater further promotes the snow melting action.
When the outside air temperature rises, the heater temperature also rises, so that the value of the current flowing through the cord heater becomes small and the amount of heat generation is suppressed, so that the temperature of the pipe 23 does not become high. The dissolved water flows through a pipe 23 to a drainage basin 24. When it cools down at night, the water flowing along the inner surface of the pipe 23 freezes and clogs the pipe, or the pipe expands during freezing, causing a pipe accident such as breaking or cracking. In such a pipe accident, by energizing the cord heater 1, the inside of the pipe 23 is always maintained at a temperature equal to or higher than the freezing temperature, so that the above-described pipe accident can be prevented beforehand.

Next, another applied apparatus will be described. FIG.
0 is an embodiment used for a floor mat. The floor mat 30 is composed of a synthetic rubber mat portion and a cord heater embedded in the mat portion. A lead wire 32 of the cord heater is drawn out from a lead outlet 31 of the mat portion, and an insertion plug 33 is provided. The cord heater 1 is embedded between the synthetic rubbers 34 and 35 in a meandering manner. The cord heater 1 is covered by an aluminum sheet 36 and further sandwiched by urethane rubber 37 as shown in FIG. It is crowded. By providing the urethane rubber 37 in this manner, the cord heater 1 does not cause a displacement during use. When the user steps on the mat portion, the local load acting on the heater portion is absorbed by the urethane rubber 37 to protect the cord heater 1. The floor mat 30 can be placed at the entrance to prevent the accumulation of snow, or used as a warming foot for a kitchen or a desk.

FIG. 12 shows an embodiment of the sheet heater. In the sheet heater 40, the cord heater 1 is arranged in a meandering shape on an aluminum foil 41, and is further covered with the aluminum foil 41 from above. The upper aluminum foil 41 is provided with the cord heater 1 as shown in FIG.
Overlap along the outer peripheral surface of. Glass leads 42 are provided at both ends of the cord heater 1 protruding from the aluminum foil 41. An adhesive 43 is applied to the back surface of the aluminum foil 41, and a release paper 44 is attached to the adhesive 43. The sheet heater 40 peels and affixes the release paper 44 to places requiring snow melting, freeze prevention, local heating, frost prevention, and the like. Even when the portion to be stuck is a curved surface or an uneven surface, it can be stuck in close contact and good heat transfer to the heat acting surface can be performed. It can also be laid on the floor and used for heating.

FIG. 14 shows an embodiment for preventing freezing and frosting of a liquid supply pipe such as a water pipe and a pipe of a heat exchanger. The cord heater 1 is provided along the outer peripheral surface of the liquid supply pipe 50. The cord heater 1 is fixed to the liquid supply pipe 50 by an aluminum tape 51. In particular, the open / close valve 52 has the cord heater 1 along the side of the valve body. A temperature sensor 53 for detecting the temperature of the liquid supply pipe 50 is provided. The thermostat 54 sends an energization control signal for the set temperature to the control box 55 based on the detection signal of the temperature sensor 53.
The control box 55 turns on the power to the cord heater 1 based on the power control signal from the thermostat 54.
Perform F control. Although illustration is omitted, when melting snow accumulated on the carport installed in the garage, the aggregate is warmed by installing a cord heater on the aggregate that supports the roofing material, and the roof is passed through this aggregate. It is also possible to melt snow that has piled up. Since the self-control type cord heater of the present invention has flexibility and can be arranged according to an arbitrary shape, its use is not limited to the above embodiment.

[Brief description of the drawings]

FIG. 1 is a front view of a self-control cord heater according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view of a cord heater having a three-wire structure.

FIG. 4 is a front view of a cord heater according to another embodiment.

FIG. 5 is a plan view of a device configuration of a self-control type code heater.

FIG. 6 is an explanatory diagram for measuring a temperature distribution of a pipe provided with a self-control type code heater.

FIG. 7 is a view showing a result of measuring a temperature distribution of a pipe, and FIG.
Fig. 7B shows a case where the lower part of the pipeline is opened, and Fig. 7B shows a case where the lower part of the pipeline is sealed.

FIG. 8 is an explanatory diagram applied to a snow melting / freezing prevention device in a building having an inclined roof structure.

FIG. 9 is an explanatory view applied to a snow melting / freezing prevention device in a building having a flat roof structure.

FIG. 10 is an explanatory diagram applied to a rubber mat.

FIG. 11 is a sectional view taken along line BB of FIG. 10;

FIG. 12 is an explanatory diagram applied to a planar heater.

FIG. 13 is a sectional view taken along the line CC of FIG.

FIG. 14 is an explanatory view applied to a device for preventing freezing and frosting of a liquid supply pipe.

FIG. 15 is a sectional view of a conventional cord heater.

[Description of Signs] 1 ... Self-control type cord heater, 2 ... Resistance wire (heating wire), 4 ... Reinforcement conductor, 6 ... Core wire, 6A ... Glass core, 7 ...
Protective layer, 8: stainless steel braid, 10: conduit, 12: thermo box, 13: energizing lamp, 14: power lamp, 1
5 ... Thermostat

Claims (13)

[Claims] 1. A self-control system comprising: a heating wire for controlling its own current by utilizing a change in a specific resistance value caused by a temperature change; an insulator covering the heating wire; and a coating covering the insulator. Type code heater. 2. A heating wire for controlling its own current by utilizing a change in a specific resistance value due to a temperature change, an insulator covering the heating wire, and a heating wire covered with the insulator in a direction in which the heating wire extends. A self-control type code heater comprising: a provided core wire; a heating wire covered with the insulator; and a coating surrounding the core wire. 3. The self-controlling type cord heater according to claim 2, wherein a heating wire covered with an insulator is wound around the core wire. 4. A plurality of heating wires covered with an insulator are arranged around the core wire.
Self-controlled cord heater as described. 5. The self-controlling type cord heater according to claim 1, wherein the covering is a metal knit. 6. The self-controlling type cord heater according to claim 1, wherein said cover comprises an inner protective layer and a metal knit covering said protective layer. 7. A snow melting apparatus using the cord heater according to claim 1 as a heating element for melting snow. 8. An antifreezing device using the cord heater according to claim 1 as a heating element for preventing freezing. 9. A frost prevention device using the cord heater according to claim 1 as a heating element for preventing frost. 10. A heating device using the cord heater according to claim 1 as a heating element for heating. 11. A carport wherein the cord heater according to claim 1 is disposed on a roof aggregate as a heating element for melting snow. 12. A drainage channel in which the cord heater according to claim 1 is disposed in a drainage pipe as a heating element for preventing freezing. 13. A heater mat in which the cord heater according to claim 1 is placed inside a rubber mat.