JP2011171255A - Heat sensitive wire and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat sensitive wire enabling sufficient temperature detection even if its length becomes short. <P>SOLUTION: Detection wires are wound on core wires, and have detection element wires of which resistance value is changed by changes in temperature. The heat sensitive wire has a plurality of detection wires, and the detection element wires of the plurality of detection wires are insulated from each other by the insulating film covering the detection element wires, and the detection element wires of the plurality of detection wires are electrically connected to one another in series. The resistance value of the detection element wires has a positive characteristic temperature coefficient. In a method of producing the heat sensitive wire, the plurality of detection wires are aligned on the core wires and wound on them while the detection element wires are insulated from each other by the insulating film covering the detection element wires, and the detection element wires of the plurality of detection wires are electrically connected to one another in series. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a heat sensitive wire used as a temperature detecting means for a heating device such as a seat heater, an electric carpet, and a floor heater, and more particularly to a device capable of sufficient temperature detection even when the length is shortened. .

  2. Description of the Related Art Conventionally, as shown in FIG. 5, for example, a heat sensitive wire used as a temperature detecting means for a warming instrument such as an electric carpet or an electric blanket is known. This is a heat sensitive wire 101 having a structure in which a detection wire 104 is wound on a central core wire 102 and a sheath 105 is covered on the outer periphery thereof, and a change in resistance value due to the temperature of the detection wire 104 is detected. Detection is performed. For example, Patent Document 1 is not an invention related to the heat sensitive wire itself, but can refer to the basic principle. The heat sensitive wire is used, for example, in the vicinity of a heat source such as a cord heater to detect the temperature of the cord heater, or in a meandering manner to detect the temperature as a surface. .

  Moreover, as a technique relevant to the present invention, for example, Patent Document 2 is cited.

JP 58-214295 A: Matsushita Electric Industrial Co., Ltd. JP 2008-311111 A: Clave

  Since the above-described heat sensitive line detects a change in the resistance value of the detection line, unless the resistance value of the detection line is increased to some extent, the amount of change in the resistance value becomes small, and sufficient detection cannot be performed. Therefore, it is necessary to increase the length of the detection line and increase the resistance value of the detection line by making the length of the heat sensitive line as long as possible. For this reason, the above-mentioned heat sensitive wire is preferably used when detecting a relatively wide range of temperature such as an electric carpet or an electric blanket, but when detecting a temperature in a narrow area, the detection wire is used. Therefore, it is very difficult to apply.

  The present invention has been made to solve the above-described drawbacks of the prior art, and an object of the present invention is to provide a heat sensitive wire capable of sufficiently detecting temperature even if the length is shortened. There is.

In order to achieve the above object, a heat sensitive wire according to claim 1 of the present invention has a sensing wire wound on a core wire, and the sensing wire has a sensing wire whose resistance value changes with temperature change. The heat sensitive wire has a plurality of the detection wires, the detection wires in the plurality of detection wires are insulated from each other by an insulating film covered with the detection wires, and the detection wires in the plurality of detection wires are Are electrically connected in series.
The heat sensitive wire according to claim 2 is characterized in that the resistance value of the sensing element wire has a positive characteristic temperature coefficient.
According to a third aspect of the present invention, there is provided a method of manufacturing a heat sensitive wire in which a detection wire is wound on a core wire, and the detection wire has a detection wire whose resistance value changes with temperature. In the method, a plurality of the detection wires are aligned and wound on a core wire in a state where the detection wires are insulated from each other by an insulating film covering the detection wires, and the detection wires in the plurality of detection wires are wound together. Are electrically connected in series.

According to the present invention, since the length of the detection line can be increased with the same structure as the conventional one, the resistance of the detection line is reduced even if the length of the thermal line is shortened in order to detect the temperature of a small area. The value can be made sufficiently high, and sufficient temperature detection is possible. In addition, when trying to reduce the diameter of the heat sensitive wire, it can be considered to reduce the diameter of the core wire, but in this case, the length of the wound detection wire is also relatively short. Even in such a case, according to the present invention, the length of the detection line can be increased. Therefore, according to the present invention, the effect of thinning the heat sensitive line can also be obtained.
In addition, if the resistance value of the detection line has a positive characteristic temperature coefficient, even if the resistance line is disconnected, it will be detected as an abnormal temperature, so the reliability as a safety device will be improved. become.
Moreover, according to the manufacturing method of the present invention, a heat sensitive wire having a desired length can be appropriately created by connecting one end after cutting the heat sensitive wire to a predetermined length. The value is very high.

It is a figure which shows embodiment in this invention, and is a side view which notches and shows the structure of a heat sensitive wire partially. It is a figure which shows other embodiment in this invention, and is a side view which partially cuts off and shows the structure of a heat sensitive wire. It is a figure which shows embodiment which applied this invention, and is a side view which partially cuts off and shows the structure of the cord-shaped heater with a thermal function. It is a figure which shows embodiment which applied this invention, and is a side view which partially cuts off and shows the structure of the cord-shaped heater with a thermal function. It is a figure which shows a prior art and is a side view which notches and shows the structure of a heat sensitive wire partially.

  The configuration of the present invention will be described with reference to FIG. First, the two detection wires 4 are aligned on the outer periphery of the core wire 2 made of an aramid fiber having an outer diameter of about 0.2 mm, and are spirally wound at a pitch of 1 mm. The detection wire 4 is obtained by coating a detection wire 4a made of a nickel wire having a wire diameter of 0.08 mm with an insulating coating 4b made of a fluororesin with a thickness of about 0.04 mm. A sheath 5 is formed on the outer periphery by coating polyethylene with a thickness of 2 mm. After the heat-sensitive wire 1 is cut to a predetermined length, the insulating coating 4b of the detection wire 4 is removed at one end, and the detection wire 4a is connected to each other by the connection terminal 6. Thereby, the detection element wires 4a are electrically connected in series.

  Hereinafter, other embodiments of the present invention will be described in detail.

  As the core wire 2, for example, inorganic fibers such as glass fibers, polyester fibers such as polyethylene terephthalate, monofilaments of organic fibers such as aliphatic polyamide fibers, aromatic polyamide fibers, wholly aromatic polyester fibers, multifilaments, spans, or Examples thereof include fibers having a structure in which the fiber material or an organic polymer material constituting the fiber material is used as a core and a thermoplastic organic polymer material is coated on the periphery thereof. In the present invention, as long as all the detection wires 4 are insulated by the insulating coating 4b, the core wire 2 does not need to stick to the insulating material. For example, a stainless steel wire or a titanium alloy wire can be used. However, considering that the detection wire 4 is disconnected, the core wire 2 is preferably an insulating material.

  As the detection element wire 4a, a conventionally known element can be used, and a material whose resistance value changes with a temperature change is used. For example, copper wires, copper alloy wires, nickel wires, iron wires, aluminum wires, nickel-chromium alloy wires, various metal wires such as copper-nickel alloys, iron-chromium alloys, carbon fiber wires, conductive resin wires, etc. . Among these, those having a positive characteristic temperature coefficient are preferable. In particular, nickel wires and platinum wires having a large coefficient can be preferably used. If the temperature has a positive characteristic temperature coefficient, the resistance value increases as the temperature rises. Therefore, when the resistance value increases, it is determined that the temperature is abnormal, and the current is turned off. Accordingly, when the detection element wire 4a is disconnected, the resistance value becomes ∞, and thus energization is stopped as in the case where an abnormal temperature occurs. This is a highly reliable system when viewed as a safety device.

  A conventionally known resin material or the like can be used as the insulating coating 4b coated on the detection element wire 4a. For example, polyurethane resin, polyamide resin, polyimide resin, polyethylene resin, polyester resin, vinyl chloride resin, fluororesin And silicone resin. Among these, if a material having heat-fusibility is used, the detection wires 4 can be fused together, so that the detection wires 4 are not scattered at the time of terminal processing such as connection with a connection terminal. Workability can be improved, which is preferable. It is also conceivable to use an organic semiconductor having a negative characteristic temperature coefficient. Further, if the insulating coating 4b is melted at a predetermined temperature, the detection element wire 4b comes into contact with the predetermined temperature, and the resistance value of the detection line is greatly reduced. An irreversible abnormal temperature can be detected by a decrease in the resistance value. When the insulating coating 4b is coated, a conventionally known method such as extrusion coating or coating may be used. In the case of the detection wire 4, a plurality of wires twisted may be handled as one detection wire 4 a. Further, depending on the embodiment, the insulating coating 4b can be omitted. For example, as shown in FIG. 2, for one detection line 4, assuming that the detection element wire 4 a is covered with an insulating film 4 b and the other detection line 4 is omitted from the insulating film, The detection element wires 4a in the respective detection lines 4 can be in a state of being insulated by the insulating coating 4b.

  A plurality of detection lines 4 are used. These may be aligned or twisted, but it is preferable to align them because the diameter of the heat-sensitive wire becomes small and the surface becomes smooth. Moreover, the detection element wires 4a of the plurality of detection lines 4 are connected at one end. For example, when two detection lines are used, the length of the detection line is one round trip by being connected at one end. Further, when three detection lines are used, if the three detection lines are assumed to be detection line A, detection line B, and detection line C, the detection line A and the detection line B are connected at one end, and the other end. Thus, by connecting the detection line B and the detection line C, the length of the detection line becomes a length of one and a half reciprocations. If the same is applied to the case where four or more detection lines are used, the length of the detection line can be further increased. Thus, by connecting a plurality of detection lines so as to be a single line, the length of the detection line can be increased, and the resistance value of the detection line can be increased. Thereby, even if the length of the heat sensitive wire is shortened, the resistance value of the detection wire can be made sufficiently high, and sufficient temperature detection is possible. As for the connection of the plurality of detection strands, for example, various conventionally known methods such as connection by terminals and soldering can be used. Further, a configuration in which each of the plurality of detection lines is connected to a circuit board or the like and each detection line is directly connected in the circuit board is also conceivable.

  As shown in FIG. 3, it is also conceivable that the heating wire 3 is aligned and wound around the core wire 2 together with the detection wire 4 to form a cord-like heater 7 with a thermal function. The heating wire 3 preferably has a configuration in which the heating wire 3a is covered with an insulating coating 3b. As the heating element wire 3a, conventionally known ones can be used, for example, copper wire, copper alloy wire, nickel wire, iron wire, aluminum wire, nickel-chromium alloy wire, copper-nickel alloy, iron-chromium alloy. Etc. can be used. Among these, a material having a small amount of spring back when wound is preferable, and a material having a restoration rate of 200% or less is preferable.

  As the insulating coating 3b coated on the heating element wire 3a, a conventionally known resin material or the like can be used similarly to the insulating coating 4b coated on the detection element wire 4a. For example, polyurethane resin, polyamide resin, Examples thereof include polyimide resin, polyethylene resin, polyester resin, vinyl chloride resin, fluororesin, and silicone resin. Among these, if a material having heat fusibility is used, the heating wires 3 or between the heating wires 3 and the detection wires 4 can be fused. Since the heating wire 3 does not vary, it is preferable because workability can be improved. It is also conceivable to use an organic semiconductor having a negative characteristic temperature coefficient. When the insulating coating 3b is coated, a conventionally known method such as extrusion coating or coating may be used. Depending on the mode, the insulating coating 3b can be omitted.

  One heating wire 3 or a plurality of heating wires 3 may be used. When a plurality of wires are used, they may be aligned or twisted, but it is preferable to align them because the diameter of the cord-like heater with heat-sensitive function 7 becomes smaller and the surface becomes smoother. When a plurality of heating wires 3 are used, it is preferable that each heating wire 3a is covered with an insulating coating 3b. As a result, each of the heating element wires 3a constitutes a parallel circuit. Therefore, even if a disconnection occurs in a part of the heating element wire 3a, it is synonymous with the disconnection of a part of the parallel circuit. Therefore, the resistance value of the cord-like heater 7 with the heat sensitive function as a whole becomes high. Therefore, the amount of current per unit cross-sectional area does not increase in the disconnected portion, and abnormal heat generation does not occur.

  It is also conceivable that the insulating coating 4b of the detection line 4 or the insulating coating 3b of the heating wire 3 is colored in different colors. Thereby, when an operator connects each wire | line, identification becomes easy and the connection operation | work of the detection wire 4 and the heat generating wire 3 becomes very easy. Further, in order to identify not only the detection lines 4 and the heating lines 3 but also the plurality of detection lines 4, it is conceivable that the plurality of detection lines 4 are colored in different colors. This is particularly effective when three or more detection lines 4 are used. For coloring the insulating film, for example, a dye or pigment may be mixed with the material constituting the insulating film, or a coloring paint or the like may be applied to the insulating film, and various conventionally known methods may be used. it can.

  A plurality of the detection wires 4 are wound around the outer periphery of the core wire 2. When the heating wire 3 is used, if the heating wire 3 and the detection wire 4 are aligned, a cord with a heat-sensitive function is formed. This is preferable because the diameter of the heater 7 is reduced and the surface is also smoothed. Thereby, for example, when a cord-like heater with a heat-sensitive function is arranged on a base material to form a sheet heater, the cord-like heater with a heat-sensitive function becomes inconspicuous, and the uncomfortable feeling caused by the protrusion of the cord-like heater with a heat-sensitive function is suppressed. be able to. In addition to the heating wire 3 and the detection wire 4, a short-circuiting detection wire or an overtemperature-preventing solder wire may be wound.

  A sheath 5 may be formed on the outer periphery of the detection wire 4 (and the heating wire 3) as necessary. The sheath may be formed by extrusion molding or the like, or may be covered with a sheath that has been previously formed into a tube shape, and the formation method is not particularly limited. The material constituting the sheath may be appropriately designed according to the usage form or environment of the heat sensitive wire. For example, polyethylene resin, polyester resin, polyurethane resin, polyamide resin, vinyl chloride resin, fluororesin, synthetic rubber, fluororubber And various other materials such as polyolefin-based thermoplastic elastomers, polyurethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, and the like. Further, a protective coating may be further formed on the outer periphery of the sheath.

  Further, as shown in FIG. 4, a heating wire 3 is wound around a central core wire 2, a coating layer 10 made of polyamide resin or the like is extrusion coated on the outer periphery thereof, and a detection element wire 4a is covered with an insulating coating 4b on the outer periphery thereof. Two coated detection wires 4 are wound in a uniform manner, a sheath 5 is extrusion coated on the outer periphery, and the detection wires of the two detection wires 4 are connected to each other by terminals 6 or the like, and the cord with a heat-sensitive function A heater 7 may be considered. In this case, the heating wire 3 may be one in which the heating wire 3a is covered with the insulating coating 3b, or may be composed only of the heating wire 3a. It is also conceivable that one of the two detection strands 4 is composed of only the detection strand 4a by omitting the insulating coating 4b.

  The heat sensitive wire 1 obtained as described above is wound around, for example, a pipe or a tank and used for temperature detection of a freeze prevention heater or a heat retaining heater. Further, it may be disposed in a predetermined shape such as a meandering shape on a substrate such as an aluminum foil, a nonwoven fabric, a resin sheet, a foamed resin sheet, or a rubber sheet, and used for detecting the temperature of the planar heater. Such a planar heater is used for, for example, an electric blanket, an electric carpet, a car seat heater, and the like. Further, when the heat-sensitive wire is disposed on the base material, a heat-sealing layer is formed on the outer periphery of the detection wire 4 (and the heating wire 3) with reference to Patent Document 2, and heating and pressurization are applied. It is also conceivable to adhere to the substrate. In the case of forming the sheath 5 described above, the heat fusion layer is formed on the outer periphery of the sheath 5. As described above, the heat fusion layer is formed as the outermost layer in the heat sensitive wire. Examples of the material constituting the heat-fusible layer include polyolefins such as polyethylene, thermoplastic polymer materials such as polyester, vinyl chloride, and polyamide. Any of these may be selected, but a material that melts at a temperature lower than the decomposition start temperature or lower than the melting point of the material constituting the insulating coating 3b and the insulating coating 4b is better. In addition, for example, the above-mentioned Patent Document 2 can be referred to for the process of disposing on the base material as described above. Of course, the method is not limited to the method of disposing the heat-bonding layer on the base material as described above. For example, a method of attaching a heat-sensitive wire to a base material having adhesiveness, and sandwiching between two base materials. Various methods are conceivable, such as a method of fixing a heat sensitive wire and a method of fixing a heat sensitive wire to a substrate by sewing.

  As described above in detail, according to the present invention, it is possible to obtain a heat sensitive wire capable of sufficient temperature detection even when the length is shortened. For example, the heat sensitive wire is arranged in a predetermined shape such as a meandering shape on a base material such as an aluminum foil or a non-woven fabric. An electric blanket, an electric carpet, a car seat heater, a heating toilet seat, a heating cooker, a floor heating, It can be suitably used as temperature detection means such as a heater for heating a secondary battery. Also, the heat sensitive wire alone can be suitably used as a temperature detection means for a freeze prevention heater or a heat retaining heater, for example, wound around or attached to a pipe, tank, case or the like.

DESCRIPTION OF SYMBOLS 1 Heat sensitive wire 2 Core wire 3 Heat generating wire 3a Heat generating wire 3b Insulating film 4 Detecting wire 4a Detecting element wire 4b Insulating film 5 Sheath 6 Terminal 7 Cord heater with heat sensitive function

Claims (3)

A detection wire is wound on the core wire, and the detection wire has a detection wire whose resistance value changes due to a temperature change.
There are a plurality of the detection wires, the detection wires in the plurality of detection wires are insulated from each other by an insulating film covering the detection wires, and the detection wires in the plurality of detection wires are electrically connected in series. Heat-sensitive wire, characterized by the fact that they are connected together. 2. The heat sensitive wire according to claim 1, wherein a resistance value of the sensing wire has a positive characteristic temperature coefficient. In the method for producing a heat sensitive wire, a detection wire is wound on a core wire, and the detection wire has a detection wire whose resistance value changes due to a temperature change.
A plurality of the detection wires are aligned and wound on a core wire in a state where the detection wires are insulated by an insulating film that covers the detection wires, and the detection wires in the plurality of detection wires are connected in series. A method of manufacturing a heat-sensitive wire, characterized by electrical connection.

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