JP2779671B2 - Manufacturing method of heat-sensitive wire - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a cord-shaped heat-sensitive wire (temperature detection wire) and a heat-sensitive heat generation wire used for an electric blanket, an electric carpet, and the like.

(Prior art) In general, planar heating devices such as electric blankets and electric carpets are
A cord-like heating wire and a heat sensing wire for temperature detection are arranged in a meandering manner, and the heating wire serves to detect the temperature of the planar heater and control the temperature of the heating wire. In recent years, a heat-sensitive heating wire in which a heating wire and a heat-sensitive wire can be shared by a single wire has been put to practical use.

The structure of the heat-sensitive wire and the heat-sensitive heat-generating wire is almost the same. For example, as shown in FIG. 2, an insulating core yarn 1, an inner winding electrode 2 spirally wound around the outer periphery thereof, and a negative winding around the outer periphery thereof. The thermosensitive resin layer 3 having a temperature coefficient is coated by extrusion molding, and then the outer winding electrode 6 is spirally wound around the outer periphery of the thermosensitive resin layer 3, and then a tape serving as the separation layer 4 is wound thereon. 5 is coated by extrusion molding.

The heat-sensitive resin layer 3 is made of, for example, a polyamide resin or a soft polyvinyl chloride resin to which a small amount of an additive such as a halide or a quaternary ammonium salt is added so that the impedance decreases with a rise in temperature. The temperature change is detected as an impedance change by the and the outer winding electrode 6 to control the temperature.

The separation layer 4 is formed by adding the additive of the heat-sensitive resin layer 3 to the insulating layer 5.
Side, or that the plasticizer in the insulating layer 5 made of a soft polyvinyl chloride resin moves to the thermosensitive resin layer 3 side, etc., so that the impedance characteristic of the thermosensitive resin layer 3 does not change with time. It is provided for the purpose,
Generally, a polyester film or the like is used.

Copper or copper alloy is generally used for the inner winding electrode 2 and the outer winding electrode 6, and a plurality of thin round wires having a diameter of about 0.1 mm are rolled together or rolled into a flat ribbon shape. The processed thing is wound.

When used as a heat-sensitive heating wire, one of the inner winding electrode 2 and the outer winding electrode 6 also serves as the heating wire.

When fixing the heat-sensitive heating wire to the base material,
A heat bonding layer 7 is used, and generally a polyethylene resin or the like is used.

(Problems to be Solved by the Invention) The conventional heat-sensitive wire or heat-sensitive heat-generating wire shown in FIG. 2 has the following disadvantages and has been desired to be improved.

(B) As the heat-sensitive resin layer 3, a material exhibiting a negative impedance temperature characteristic is used. However, in recent years, a real-oriented surface material or a cover material having a long bristle is used in an electric carpet or the like, and the feeling of heating is reduced. There is a tendency that the heater temperature becomes higher for the purpose of not causing it to occur.
Since the temperature is set such that the impedance is lowered (higher temperature side than before), the ability to detect an abnormal temperature such as partial heat insulation (overheating) is reduced.

(B) This type of heat-sensitive wire or heat-sensitive heat-generating wire is used to be sandwiched between a surface material and a back surface material such as felt and used on the floor surface. In particular, the outer wound electrode 6 is more likely to be disconnected due to fatigue when subjected to the heat.

(Means for Solving the Problems) The present invention has been proposed in order to solve the above-described problems, and even when the heater temperature is set to a high temperature, partial heat insulation (heating) is performed.
By improving the thermosensitive resin characteristics that the detection ability such as etc. does not decrease, and by making the outer winding electrode into the thermosensitive resin layer,
The present invention relates to a method for manufacturing a heat-sensitive wire or a heat-sensitive heat-generating wire which has a large ability to detect abnormal temperatures and is hardly disconnected even when subjected to an external force.

(Operation) FIG. 3 shows the impedance-temperature characteristics of the thermosensitive resin. This kind of thermosensitive resin is based on ionic conductivity. When the temperature exceeds the glass transition temperature (Tg point) of the resin,
This utilizes the property that ionic conduction increases with increasing temperature. Therefore, in order to prevent the detection capability of partial heat insulation (overheating) from lowering even when the set temperature of the heat-sensitive wire or the heat-sensitive heat generation wire is increased, the glass transition temperature Tg of the resin is increased to increase the ion conduction. Approaching the temperature at which
The ratio of the impedance of the partial adiabatic (overheating) portion to the uniform set temperature over the entire surface is smaller than that of the related art (that is, the detection sensitivity is increased).

However, when the glass transition temperature Tg point is set to a high temperature side, the properties of the resin become harder, so that the outer winding cannot be embedded in the heat-sensitive resin layer. A method of spirally winding one or both of the layer and the outer winding electrode while heating the outer winding electrode into the heat-sensitive resin layer becomes possible.

(Example) Next, an example of the present invention will be described. It should be noted that the embodiments are merely examples, and it is needless to say that various changes or improvements can be made without departing from the spirit of the present invention.

Hereinafter, an embodiment in which an embodiment of the present invention is applied to a heat-sensitive heating wire will be described with reference to FIG.

Core yarn 1 consisting of polyester denier 1500 denier
Then, a plurality of conductors of 0.12 mmφ made of Sn0.3% copper alloy are spirally arranged and wound to form an inner winding electrode 2 ′. Next, 20 parts of a heat-resistant plasticizer is added to the polyvinyl chloride resin ( Glass transition temperature Tg point is about 40 by viscoelasticity test method
° C), a quaternary ammonium salt is added thereto, and the thermosensitive resin layer 3 ′ which is made into a negative characteristic thermistor is extruded by extrusion to a thickness of 0.3 mm, and then rolled into a ribbon shape having a thickness of 0.05 mm and a width of 0.5 mm. The electrode 6 'is spirally wound so as to generate the above-mentioned heat-sensitive resin layer 3' (A) while heating (by a method such as blowing hot air) the ambient temperature of the spiral wound portion to about 60 ° C. Then, a separation layer 4 made of a polyester table 25 μm, an insulating layer 5 made of soft polyvinyl chloride is made 0.4 mm thick, and a thermal bonding layer 7 made of low density polyethylene is made 0.1 mm thick.

On the other hand, in the conventional example, 48 parts of the heat-resistant plasticizer was added to the polyvinyl chloride resin (the glass transition point Tg was about 5 ° C. according to the viscoelasticity test method). That is, in the present invention, the resin is heated at a temperature higher than the glass transition temperature Tg.

In the above-described embodiment, the heat-sensitive heating wire has been described. However, it goes without saying that the present invention can be applied to a heat-sensitive wire.

(Effects of the Invention) According to the present invention, the impedance-temperature characteristics of the heat-sensitive resin material are improved to characteristics that facilitate detection of partial heat insulation (overheating),
In addition, since the outer winding is in the heat-sensitive layer, it becomes possible to detect and control (a) partial heat insulation (overheating) at a lower temperature.

(B) In addition to the fact that the heat-sensitive resin layer is hardened, the outer winding electrode is penetrated into the heat-sensitive layer, so that it is difficult to deform when subjected to an external force, and the durability is improved.

(C) Since the heat-sensitive resin is digged while being heated, the residual strain of the heat-sensitive resin is small, and the impedance is less likely to fluctuate due to the annealing effect due to heating.

(D) Since the inner winding is formed by extruding the heat-sensitive resin and the outer winding is embedded in the heat-sensitive resin layer according to the present invention, the adhesion between the electrode and the heat-sensitive resin is good, and the detection of the impedance value is stable. Even if bent, the spiral structure does not shift. Even when the separation layer is wound, the spiral structure does not shift and a product with little variation can be made. Since the separation layer is wound tightly, there is an effect that the bending life is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention, FIG. 2 shows a conventional example, and FIG. 3 shows impedance-temperature characteristics of a thermosensitive resin. DESCRIPTION OF SYMBOLS 1 ... Core thread 2 '... Inner winding electrode 3' ... Thermosensitive resin layer 4 ... Separation layer 5 ... Insulating layer 6 '... Outer winding electrode 7 ... Thermal bonding layer A ...

Claims (1)

(57) [Claims] An inner winding metal conductor electrode is spirally wound around a core material, and an outer winding metal conductor electrode is spirally wound around the surface thereof via a heat-sensitive resin layer, and is subjected to insulation coating finish. In the heat-sensitive wire, the heat-sensitive resin layer or the one or both of the outer-wound metal conductor electrodes are spirally wound while being heated, and the outer-wound metal conductor electrode is made to bite into the heat-sensitive resin layer. Hot wire manufacturing method.