JP2000012200A - Heating electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cut at arbitrary length for use, and to adjust to feeding conditions and required calorific values at the time of laying, to lower a price, by constituting the heating wire by a heating core wire and feeding core wires, and by carrying out feeding to the heating core wire in any longitudinal place by the feeding core wires. SOLUTION: This heating electric wire is constituted by feeding core wires 1, a heating core wire 2, first coating layers 3, and a second coating layer 4. The two feeding core wires 1 are arranged on both sides of the one heating core wire 2 which is fed by the feeding core wires 1. Here, the feeding core wires 1 have electric resistance of approximately zero, and the heating core wire 2 has electric resistance of the required value, therefore it generates heat when it is impressed with voltage. Further, the feeding core wires 1 and the heating core wire 2 are insulated by first coating layers 3 respectively having required heat-resistant characteristics and required pressure-resistant characteristics. Then, the heating core wire 2 is connected with the feeding core wires 1 by solderless contact at arbitrary intervals and in arbitrary places after the laying, which provides the heating core wire 1 with calorific values different in the longitudinal direction, thus arbitrary calorific values can be set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating wire which is laid in contact with a body to be heated and which is energized to heat the body to be heated.

[0002]

2. Description of the Related Art The term "heating wire" means a wire which is laid in contact with an object to be heated and which is heated by energizing the object to be heated. That is, a ribbon heater or a film heater as a planar heating element was used for heating. For example, a ribbon heater was laid while being in contact with an object to be heated over several tens of meters, and a predetermined amount of heat was generated by energizing the ribbon heater to heat the object to be heated. The energization can be performed by an electric wire wired along the ribbon heater or by laying the ribbon heater in a folded state and connecting to a power source at either end.

[0003]

A conventional heating method using a ribbon heater or a film heater has the following problems.

(1) The power supply voltage and the amount of heat generated per unit length are determined for each product, and it is difficult to change the power supply after purchase according to site conditions.

(2) Since it is manufactured in a fixed size, it is impossible to cut and use a required length.

Accordingly, an object of the present invention is to solve the above-mentioned drawbacks of the prior art, to be able to be cut to an arbitrary length for use, and to adjust the amount of heat generated at the time of installation according to the power supply conditions and the required amount of heat generated. An object of the present invention is to provide an inexpensive heating wire.

[0007]

In order to achieve the above object, the present invention comprises a heating core and a power feeding core, and power is supplied to the heating core at an arbitrary position in the longitudinal direction by the power feeding core. It is configured to be able to.

The heating core may be arranged between the two power supply cores.

Further, the heating core wire and the power feeding core wire may be crimped at predetermined intervals in the longitudinal direction.

[0010]

FIG. 1 is a perspective view showing an embodiment of a heating wire according to the present invention. The heating wire includes a power supply core 1, a heating core 2, a first coating layer 3, and a second coating layer 4. Two power supply core wires 1 are arranged on both sides of one heat generation core wire 2. This feeding core 1
As a result, power is supplied to the heating core wire 2. The electric resistance of the power supply core wire 1 is almost zero. The heating core wire 2 has a necessary electric resistance and generates heat when a voltage is applied. The power supply core 1 and the heating core 2 are respectively
First coating layer 3 having required heat resistance and required pressure resistance
Insulated. From the outside of the first coating layer applied to these three core wires, the entire structure is formed into a VVF type by collectively coating with a second coating layer 3 having necessary heat resistance characteristics and necessary pressure resistance characteristics. .

FIG. 2 is an explanatory view showing one example of the construction of the heating wire of FIG. The first coating layer and the second coating layer have been omitted for simplicity. Power is supplied from a power supply 6 from one end, and the heating core 2 and the power supply core 1 of the heating wire are connected at equal intervals. This connection is desirably a crimp connection, and can be easily connected using commercially available components such as wiring components and a ring sleeve. In the example of FIG. 2, the heating core wire 2 is divided into eight equal parts, and a voltage is applied to the equally divided sections from the power supply power source 6.

FIG. 3 is an equivalent circuit diagram of the heating wire of FIG. FIG. 3 can be further rewritten to the circuit diagram shown in FIG. Here, the voltage drop in the power supply core 1 and the change in resistance temperature of the heating core 2 are small and are ignored. The equivalent circuit is a circuit in which eight resistors R / 8 are connected in parallel and a voltage E is applied. Here, E represents the voltage of the power supply 6, and R represents the resistance over the entire use length of the heating core 2.
Assuming that the number of divisions of the heating core wire 2 is n and the heating value of the entire heating wire is θ (watt, w), θ = E ² / (R / n) · n
= E ² / R · n ² holds. Therefore, if the heating core wire 2 of the heating wire is divided at equal intervals, a heating value proportional to the square of the number of divisions can be obtained. A heating electric wire is laid on site, and the number of divisions can be determined from the voltage of the power supply power supply 6 that can be used and the required heat generation amount. The electric wire is VV
Since it is an F type, the shape of heat generation is a band shape.

On the other hand, assuming that the resistance of the heating core wire 2 per unit length is r (Ω / m), the length of the divided section is l (m).
Then, the calorific value q (w / w /
m) is q = E ² / (r · l) / l = E ² / (r · l ² )
Therefore, the amount of heat generated changes by changing the length of the divided section, and the amount of heat generated in the longitudinal direction of the heating wire can be arbitrarily changed. For example, when it is necessary to increase the heating temperature only in a certain section, the length of that section may be shorter than the length of another section.

The power supply 6 may be DC or AC, and a power supply that can be used on site may be used.

As described above, after the heating wire is laid, the calorific value is changed by changing the length of the crimping connection between the heating core wire and the power feeding core wire or the number of divisions when performing the crimping connection in equal divisions. Can be arbitrarily adjusted.

[0016]

According to the heating wire of the present invention, a power supply core is arranged on both sides of a heat generation core, a heat-resistant insulating coating layer is applied, and after the installation, the heat generation core and the power supply core are crimped at any intervals and locations. Due to the connection, the following excellent effects are exhibited.

(1) Different heat values can be provided in the longitudinal direction.

(2) An arbitrary amount of heat can be set.

(3) Any length can be used.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a heating wire according to the present invention.

FIG. 2 is an explanatory view showing an example of construction of the heating electric wire of FIG.

FIG. 3 is an equivalent circuit diagram of the heating wire of FIG. 2;

FIG. 4 is a circuit diagram in which the equivalent circuit of FIG. 3 is rewritten.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply core wire 2 Heating core wire 3 First coating layer 4 Second coating layer 5 Crimp connection part 6 Power supply for power supply

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Shuji Shioji 880 Sunazawa-cho, Hitachi City, Ibaraki Prefecture F-term in the Takasago Plant of Hitachi Cable Co., Ltd.

Claims (3)

[Claims] 1. A heating core wire and a power feeding core wire, wherein power is supplied to the heating core wire so that the power feeding core wire can be provided at an arbitrary position in a longitudinal direction. Heating wires. 2. The heating electric wire according to claim 1, wherein the heating core is disposed between the two power supply cores. 3. The heating wire according to claim 1, wherein the heating core wire and the power feeding core wire are crimp-connected at predetermined intervals in the longitudinal direction.