JPH03163784A - Manufacture of thermo-sensitive wire - Google Patents

Abstract

PURPOSE:To obtain a thermo-sensitive wire or a thermo-sensitive heating wire with a large detecting capability of an abnormal temperature and hard to be opened when an external force is applied by allowing an out-wound electrode to bite into a thermo-sensitive resin layer. CONSTITUTION:Multiple copper alloy conductors are spirally parallel-wound on core yarns 1 made of polyester twisted yarns to form an in-wound electrode 2', and a thermo-sensitive resin layer 3' added with a heat-resistant plasticizer 20 pts. and the fourth-class ammonium salt and converted into negative- characteristic thermistor is extrusion-molded. An out-wound electrode 6' rolled in a ribbon shape is heated at the atmospheric temperature about 60 deg.C and spirally wound so as to bite (A) into the thermo-sensitive resin layer 3'. A separation layer 4 made of a polyester tape, an insulating layer 5 made of soft polyvinyl chloride, and a thermo-adhesive layer 7 made of low-density polyethylene are formed respectively.

Description

[Detailed description of the invention] (Field of application to m industry) The present invention relates to a method for manufacturing cord-shaped heat-sensitive wires (temperature detection wires) and heat-sensitive heating wires used in electric blankets, electric carpets, etc. ．． (Prior art) Generally, in a sheet heating device such as an electric blanket or an electric carpet, a cord-shaped heating wire and a heat-sensitive wire for temperature detection are arranged in a meandering manner. Its role is to detect the temperature of the heating wire and control the temperature of the heating wire. In addition, in recent years, heat-sensitive heating wires have been put into practical use, in which a single wire can serve as both a heating wire and a heat-sensitive wire. The structures of the heat-sensitive wire and the heat-sensitive heating wire are almost the same. For example, as shown in FIG. A thermosensitive resin layer 3 having a temperature coefficient is coated by extrusion molding, and then an electrode 6 is spirally wound around the outer periphery of the thermosensitive resin layer 3, and then a tape #M4 is wrapped around the outer periphery of the thermosensitive resin layer 3. 5 is coated by extrusion forming process. The heat-sensitive resin layer 3 is made of, for example, polyamide resin or soft polyvinyl chloride resin with a small amount of additives such as halides and quaternary ammonium salts added so that the impedance decreases as the temperature rises. The temperature change is detected as an impedance change by the outer wound electrode 6 and the temperature is controlled. In addition, the separation layer 4 is made of a soft polyvinyl chloride resin that prevents the additives in the heat-sensitive citrus layer 3 from migrating to the insulation N5 side. This is provided for the purpose of preventing the impedance characteristics of the thermosensitive resin layer 3 from changing over time due to migration of the plasticizer in N5 to the thermosensitive resin layer 3 side, etc.
Generally, polyester film etc. are used. In addition, copper or a copper alloy is generally often used for the inner-wound electrode 2 and the outer-wound electrode 6, and they are made by winding a plurality of thin round wires with a diameter of about 0.1 mm, or by winding them into a rectangular ribbon shape. It is rolled and rolled. When used as a heat-sensitive heating wire, either the inner-wound electrode 2 or the outer-wound electrode 6 serves as the heat-generating wire. In addition, when wiring and fixing the heat-sensitive heating wire to the base material, heat bonding MJ! l1 is used, and polyethylene resin is generally 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 drawbacks, and improvements have been desired. However, in recent years, electric carpets, etc., have been using long-pile, authentic-looking surface materials and cover materials, and the heater temperature has been raised to a higher temperature in order to prevent the I1 tuft feeling from becoming low. However, if conventional thermosensitive resin is used, the IA degree setting will be lowered (higher temperature than conventional), so
The ability to detect abnormal temperatures such as partial insulation (overheating) is reduced. ([I) This type of heat-sensitive wire or heat-sensitive heat-generating wire is used on the floor by being sandwiched between a surface material such as felt or an RX material, but it is repeatedly stepped on. In particular, the outer wound electrode 6 is more likely to break due to fatigue when subjected to external forces such as. (Means for Solving the Problems) The present invention was proposed in order to solve the above-mentioned problems, and is a thermosensitive resin whose detection ability for partial insulation (heating) does not deteriorate even when the heater temperature is set to a high temperature. improved characteristics, and
This invention relates to a method for manufacturing a heat-sensitive wire or a heat-sensitive heating wire that has a high ability to detect abnormal temperatures and is difficult to break even when subjected to external force by embedding an outer wound electrode in a heat-sensitive resin layer. (Function) Figure 3 shows the impedance-temperature characteristics of thermosensitive resin. This type of thermosensitive resin is due to ionic conductivity, and when the temperature exceeds the glass transition point (Tg point) of the resin,
This takes advantage of the property that ionic conduction increases with temperature rise. Therefore, even if the set temperature of the heat-sensitive wire or heat-sensitive heating wire is set to a high temperature, it will partially break! In order to prevent the detection ability of 8 (overheating) from decreasing, the glass transition point i of the resin must be
By raising the Tg point and approaching the temperature at which ion conduction occurs, the ratio of the impedance of the partially insulated (overheated) part to the uniform set temperature across the entire surface becomes smaller than before (that is, the detection sensitivity becomes higher). ．． However, if the glass transition temperature Tg point is set to a high temperature side, the properties of the resin become hard, making it impossible to embed the outer winding in the heat-sensitive resin layer. By spirally winding one or both of the layers and the outer wound electrode while heating, it becomes possible to embed the outer electrode into the thermosensitive resin layer. (Example) Next, an example of the present invention will be described. It should be noted that the embodiments are merely illustrative, and it goes without saying that various changes and improvements can be made without departing from the spirit of the invention. Hereinafter, an embodiment of the present invention applied to a heat-sensitive heating wire will be explained based on FIG. 1. A plurality of conductors of 0.12 msφ made of Sn0.3% copper alloy are spirally wound around a core yarn L made of 1500 denier polyester thread to form an electrode 2'' inside. Heat-sensitive resin layer 3 made of vinyl chloride resin, 20 parts of a heat-resistant plasticizer (glass transition temperature Tg point is approximately 40°C according to the viscoelasticity test method), and a quaternary ammonium salt to form a negative characteristic thermistor. After extruding it to 0.3 mm and rolling it into a ribbon shape to a width of 0.05 mmrgXO. (by blowing hot air, etc.) into the heat-sensitive resin layer 3, which is rolled up into a spiral shape so that the embedding (A) occurs, and then a certain separation M4 made of soft polyvinyl chloride is rolled up from a polyester tape 25n. The insulation N5 is 0.4 m thick (the thermal adhesive layer 7, which is stronger than low-density polyethylene, is 0.1 + sm thick. In contrast, in the conventional example, 48 parts of heat-resistant plasticizer is added to polyvinyl chloride resin). (Glass transition temperature? The point was about 5°C in the viscoelasticity test method).In other words, in the present invention, heating is performed at a temperature higher than the glass transition temperature Tg point of the resin. Although the exothermic wire has been described, it goes without saying that the present invention is also applicable to heat-sensitive wires. (Effects of the Invention) According to the present invention, the impedance-temperature characteristics of the heat-sensitive resin material can detect partial insulation (overheating). (1) Partial insulation (overheating) can be detected and controlled at lower temperatures. (El) The thermosensitive resin layer is hard. In addition, since the outer wound electrode is recessed into the heat-sensitive layer, it is less likely to deform when external force is applied, improving durability. There is less residual strain, and impedance fluctuations due to heating and annealing effects are reduced. (2) The inner winding is made of extruded heat-sensitive resin, and the outer winding is embedded in the heat-sensitive resin layer according to the present invention. Therefore, the adhesion between the electrode and the thermosensitive resin is good, and the detection of impedance values is stable.The spiral structure does not shift even when it is bent.The spiral structure does not shift even when winding layers, and there is no variation. Since the separation layer is tightly wound, it has the effect of improving bending life.

[Brief explanation of the drawing]

Figure 1 shows an example of the present invention, Figure 2 shows a conventional example, and Figure 3 shows the impedance-temperature characteristics of a thermosensitive resin. l... Core yarn 2゛... Inner winding electrode 3゜... Thermosensitive resin layer 4... Separation layer 5... Insulating layer 6゜...・Outer S electrode 7...Thermal adhesive layer A...Beg-in) Figure 1 Figure 2 Figure 3v! J 1L

Claims (1)

[Claims] In the heat-sensitive wire, an inner-wound metal conductor electrode is spirally wound around a core material, an outer-wound metal conductor electrode is spirally wound on the surface of the core material through a heat-sensitive resin layer, and an insulating coating is applied. A method for manufacturing a heat-sensitive wire, characterized in that one or both of the heat-sensitive resin layer and the outer-wound metal conductor electrode are spirally wound while heating, so that the outer-wound metal conductor electrode bites into the heat-sensitive resin layer.