JP2006339094A - Sheet-like heating element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability such as durability while maintaining heating characteristics of the whole heating element by effectively arranging electrodes in a sheet-like heating element which can be used as a heat source for warming, heating and drying. <P>SOLUTION: Since this sheet-like heating element has an electrically integrated structure wherein a plurality of polymer resistors 10, 13, 17 are connected with a lead wire, design constraint in arranging electrodes 6, 12, 16 of each heating part and resistors 7, 13, 17 can be reduced, the performance of the irregular shape sheet-like heating element can be sufficiently brought out, substrate waste loss can be abolished, and reliability such as durability can be improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a planar heating element that can be used as a heat source for heating, heating, drying, and the like.

  Conventionally, as shown in FIGS. 3 and 4, this type of planar heating element is a pair of combs obtained by printing and drying a conductive paste on an electrically insulating substrate 50 such as a polyester sheet. The electrodes 51 and 52 and the polymer resistor 53 obtained by printing and drying the polymer resistor ink are provided at positions where power is supplied by the electrodes 51 and 52, and the comb electrode 51 is further covered with a covering material 54 similar to the material of the substrate 50. , 52 and the polymer resistor 53 are covered and protected.

  When a polyester film is used as the base material 50 and the covering material 54, for example, a polyethylene-based heat-fusible resin 55 is bonded to the covering material 54 in advance, and the base material 50 and the covering material 54 are pressed by heating. Are bonded via a heat-fusible resin 55.

  As a result, the comb-shaped electrodes 51 and 52 and the polymer resistor 53 are isolated from the outside world and given long-term reliability. As the aforementioned hot pressurizing means, as shown in FIG. 5, a laminator 58 composed of two heating rolls 56 and 57 is generally used.

  That is, the base material 50 on which the comb electrodes 51 and 52 and the polymer resistor 53 are formed on the upper surface is introduced between the two heating rolls 56 and 57 from the left direction. On the other hand, the covering material 54 is introduced between the heating rolls 56 and 57 from the upper part with the surface of the heat-fusible resin 55 as the lower surface. Adhesion between the base material 50 and the covering material 54 is performed by melting the heat-fusible resin 55 with the heat and pressure of the heating rolls 56 and 57 and then cooling it.

  As the polymer resistor ink forming the polymer resistor 53, a base polymer and a conductive material such as carbon black, metal powder, and graphite are dispersed in a solvent. In particular, a crystalline resin is used as the base polymer. Many of them have PTC characteristics (see, for example, Patent Documents 1, 2, and 3).

The PTC characteristic is a resistance temperature characteristic in which the resistance value increases as the temperature rises, and the resistance value increases abruptly when reaching a certain temperature (Positive Temperature Coefficient, meaning that the resistance has a positive temperature coefficient) The polymer resistor 53 having PTC characteristics can provide a planar heating element having a self-temperature adjusting function.
Japanese Patent Laid-Open No. 56-13689 JP-A-6-96843 JP-A-8-120182

  However, in the conventional configuration, since the sheet heating element is configured by the comb-shaped electrodes 51 and 52 and the polymer resistor 53 printed on the electrically insulating base material 50 such as a polyester sheet, the sheet heating element resistor is used. When there are a plurality of locations where the main polymer resistor 53 is provided, for example, the side where the sleeve-shaped planar heating element in which the auxiliary polymer resistor 53 is disposed on both sides of the main polymer resistor 53 is required. In the seat heater used for the seat, the arrangement of the comb-shaped electrodes 51 and 52 of the planar heating element and the polymer resistor 53 is limited in terms of design in consideration of voltage drop and strength, and the performance of the planar heating element is impaired. There was a problem.

  That is, as shown in FIG. 5, one of the comb-shaped electrodes 51 and 52 and the polymer resistors 53b and 53c located in the center between the polymer resistors 53a and 53d on both sides is electrically connected. Two portions, the portion for receiving the supply of electricity and the portion for supplying electricity to the next polymer resistor 53c, are absolutely necessary. When one of the comb-shaped electrodes 51 becomes longer and voltage is dropped, a planar heating element is formed. In addition to a decrease in the overall temperature and deterioration of the heat generation characteristics, the portion where the comb-shaped electrode 51 is disposed is a portion where electricity is supplied and a portion where electricity is supplied to the next polymer resistor 53. For this reason, there is a concern that the heating characteristics of the entire planar heating element cannot be obtained due to a decrease in the heat generation area of the polymer resistors 53b and 53c.

  In addition, in order to discard the base material 50 between the polymer resistors 53a, 53b, 53c, and 53d while leaving a portion to be connected, between the polymer resistors 53a and 53b, between the polymer resistors 53b and 53c, or The base material 50 portion connecting the polymer resistors 53c and 53d becomes thin and weak in strength, and there is a concern that the printed electrodes 51 and 52 may be disconnected and deteriorated, resulting in durability deterioration.

  The present invention solves the above-described conventional problems, and by connecting the electrodes between the resistors with lead wires, the electrodes can be effectively disposed, and the heating characteristics of the entire heating element are maintained while being durable. The purpose is to improve reliability such as reliability.

  In order to solve the above problems, the planar heating element of the present invention includes an electrode printed on an electrically insulating substrate, a polymer resistor fed by the electrode, and a feeding portion of the electrode on one side. A terminal member configured to connect a lead wire to be formed and to form a conductive resin material on the other surface and to be surface-bonded to the electrode, and to cover the electrode, the terminal member, and the polymer resistor, And a plurality of polymer resistors and electrodes on an electrically insulating substrate, and a terminal member is disposed at a predetermined position of the plurality of disposed electrodes. The terminal members are connected to each other by lead wires so that the polymer resistor is electrically integrated.

  With the above-described configuration, a plurality of resistors and electrodes are disposed on one electrically insulating substrate, a terminal member is disposed at a predetermined position of the electrode, and a plurality of terminals are connected to each other with lead wires. Since the resistors are electrically integrated, the design constraints on the arrangement of the respective electrodes and resistors are reduced, and differently shaped resistors can be effectively joined together. The performance of the planar heating element having the shape can be sufficiently extracted.

  That is, by connecting a plurality of resistors with lead wires and electrically integrating the polymer resistors, each resistor is an electrode that prints electricity supply of an adjacent resistor on an electrically insulating substrate In order to be able to connect freely in parallel or in series with lead wires without reducing the voltage, design constraints are reduced, voltage drops due to long electrodes, and electricity is supplied to adjacent resistors There is no need to worry about a decrease in the heat generation area, and the heating characteristics of the entire sheet heating element can be brought out.

  Further, since the strength of the portion connecting the resistors is also constituted by the lead wire, it can be remarkably strengthened, and the reliability can be improved in terms of durability.

  Since the planar heating element of the present invention has a structure in which a plurality of resistors are connected by lead wires on one electrical insulating base material and the polymer resistors are electrically integrated, Design constraints in the arrangement of electrodes and resistors can be reduced, the performance of the irregularly shaped planar heating element can be fully exploited, and reliability such as durability can be improved.

  The planar heating element according to the first aspect of the present invention comprises an electrode printed on an electrically insulating substrate, a polymer resistor fed by this electrode, and a lead wire feeding a feeding portion of the electrode on one side. A terminal member configured to form a conductive resin material on the other surface and surface-bonded to the electrode, and a covering material disposed in close contact with the electrically insulating base material covering the electrode, the terminal member, and the polymer resistor A plurality of polymer resistors and electrodes are disposed on the electrically insulating substrate, and terminal members are disposed at predetermined positions of the plurality of disposed electrodes, and the respective terminal members are connected with lead wires. The polymer resistors are connected and electrically integrated.

  Then, a plurality of resistors and electrodes are arranged on one electrical insulating base material, a terminal member is arranged at a predetermined position of the electrode, and each terminal member is connected by a lead wire to form a plurality of resistors. Since the body is electrically integrated, the design constraints on the arrangement of the electrodes and resistors are reduced, and differently shaped resistors can be effectively joined together. The performance of the planar heating element can be sufficiently extracted.

  That is, by connecting a plurality of resistors with lead wires and electrically integrating the polymer resistors, each resistor is an electrode that prints electricity supply of an adjacent resistor on an electrically insulating substrate In order to be able to connect freely in parallel or in series with lead wires without reducing the voltage, design constraints are reduced, voltage drops due to long electrodes, and electricity is supplied to adjacent resistors There is no need to worry about a decrease in the heat generation area, and the heating characteristics of the entire sheet heating element can be brought out.

  Further, since the strength of the portion connecting the resistors is also constituted by the lead wire, it can be remarkably strengthened, and the reliability can be improved in terms of durability.

  The planar heating element according to the second invention has a plurality of polymer resistors and electrodes arranged on the electrically insulating substrate of the first invention, and a terminal member is placed at a predetermined position of the arranged electrodes. The terminal members are connected to each other with lead wires so that the plurality of resistors are electrically integrated, and part or all of the lead wires for connecting the terminal members to each other are separated from the covering material. It is set as the structure so that it may cover with a protection member.

  And in addition to the effect which connects the terminal members of 1st invention with a lead wire, and electrically integrates several resistors, a part or whole of the lead wire which connects terminal members is separated from a coating | covering material. In addition, the strength of the portion connecting the resistors is also protected by the protective member, and can be remarkably strengthened. In addition to improving the reliability, the lead wire connecting the electrodes becomes easy to be caught, and there is no risk of damaging the sheet heating element. And workability can be improved.

  The planar heating element according to the third aspect of the invention is configured so that either one or both of the electrodes for supplying power to the planar heating element of the first and second inventions are in a closed circuit.

  Since either or both of the electrodes that supply power to the planar heating element are configured as a closed circuit, even if a part of the electrode is cracked or disconnected for some reason, electricity does not rotate. Therefore, the sheet heating element can be used without significantly affecting the heat generation of the sheet heating element, and the durability of the sheet heating element can be greatly improved.

  In the fourth invention, in particular, the conductive resin material of the terminal member of the first to third inventions has a thermosetting property with respect to the electrode.

  And since the conductive resin material of the terminal member shows a thermoadhesiveness with respect to the electrode and has a thermosetting structure, it is in an uncured state before the conductive resin material of the terminal member is joined to the electrode. Adhesion is possible by applying heat at the time of surface bonding, and volatile components are removed in the process of thermosetting by heat-adhering and curing when applying heat to the electrode, such as when attaching lead wires. Therefore, it does not foam and becomes a dense structure, and sufficient strength can be obtained. The original adhesive strength of the conductive resin material can be exhibited, and the terminal member can be reliably bonded to the electrode with a simple configuration.

  The fifth aspect of the invention has a configuration in which an insulating protection treatment is applied to the lead wire attachment portion of the first to fourth aspects of the invention.

  In addition, since the insulating protective material is applied to the lead wire attachment portion, the electrode and the polymer resistor fed by the electrode from the lead wire attachment portion are protected by the insulating protective material and blocked from the outside air. Thus, it is possible to prevent problems such as contamination deterioration due to moisture and foreign matter, and short-circuiting due to electrode migration, thereby improving performance stability and durability.

  And the 6th invention mounts the planar heating element of the 1st-5th invention especially as a heat source of a heating appliance.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
In FIG. 1 and FIG. 2, the sheet heating element includes a main heating part 2 disposed on the electrically insulating substrate 1, a right side heating part 3 and a left side heating part 4 disposed on the right and left sides thereof. It is configured.

  The main heat generating portion 2 is coated with a polymer resistor ink so as to overlap a pair of electrodes 6 formed by printing and drying a silver paste on a thin-walled electrically insulating substrate 1 such as a polyester film laminated on a polyester nonwoven fabric 2a. The polymer resistor 7 formed by printing and drying is formed. Then, a thin-walled electrically insulating overcoating film such as a polyester film in which an adhesive resin layer 8 such as an acrylic adhesive having adhesiveness with the electrode 6, the polymer resistor 7, and the electrically insulating substrate 1 is formed in advance. The covering material 9 laminated with the coating material is bonded together.

  The electrode 6 is provided with wide main electrodes 6a and 6b so as to face each other, and a plurality of comb-shaped branch electrodes 6c and 6d are alternately provided from the respective main electrodes 6a and 6b, and overlap each other. By supplying power to the polymer resistor 10 arranged as described above from the branch electrodes 6c and 6d, current flows and heat is generated.

  This polymer resistor 10 has PTC characteristics, and when the temperature rises, the resistance value rises and has a self-temperature adjusting function so as to reach a predetermined temperature. It has a function as a heating element.

  As shown in FIG. 1, the arrangement pattern of the electrodes is arranged so that the plurality of comb-shaped branch electrodes 6d are arranged alternately from the center of the main electrode 6b located on the middle side. A plurality of comb-shaped branch electrodes 6d arranged inward from the main electrode 6a located outside are positioned so as to surround the main electrode 6b located on the side from the periphery, and are located outside. The main electrode 6a is configured as a closed circuit.

  Further, the right side heat generating part 3 and the left side heat generating part 4 arranged to the right and left of the main heat generating part 2 are configured similarly, and the right side heat generating part 3 is silver on the electrically insulating base material 11. A pair of electrodes 12 formed by printing / drying a paste and a polymer resistor 13 formed by printing / drying a polymer resistor ink so as to overlap the electrodes 12 are formed, and an electrically insulating overcoat material is laminated. The covered covering material 14 is bonded together.

  The left side heat generating portion 4 is also formed by printing / drying a pair of electrodes 16 formed by printing / drying silver paste on the electrically insulating base material 15 and the electrode 16 so as to overlap the electrodes 16. The polymer resistor 17 is formed, and a covering material 18 laminated with an electrically insulating overcoat material is bonded together.

  Further, the terminal members 19 are surface-bonded to the main electrode feeding portions of the main heat generating portion 2, the right side heat generating portion 3, and the left side heat generating portion 4, and lead wires 20 are connected to the respective terminal members 19, and these leads are connected. The line 20 is configured to be connected to the power source from the main electrode power feeding portion of the right heat generating portion 3 and the left side heat generating portion 4 having the same polarity via the main electrode power feeding portion of the main heat generating portion 2. Further, an insulating protective material 21 such as a silicon adhesive is applied to the attachment portion of the lead wire 20.

  Since the processing method is basically the same as the order of the processing steps, the main heating portion 2 will be described. First, a conductive resin material 19a is formed on the surface of the terminal member 19 that contacts the power feeding portion of the electrode 6. The conductive resin material 19a is electrically and physically joined between the electrode 6 and the terminal member 19, and the conductive resin material 19a exhibits thermal adhesiveness to the electrode 6 and is thermosetting. There is used a conductive paste prepared by dispersing silver powder as a conductivity-imparting material in a copolyester and further adding an appropriate amount of isocyanate as a curing agent.

  The conductive resin material 19a at this stage retains thermoplasticity because it is dried at a low temperature so as not to cause a curing reaction due to isocyanate. You are ready to wear. In this case, in particular, when the same kind of resin is used as the conductive resin material 19a for the electrode 6, the heat fusion property is very good and sufficient heat fusion strength can be obtained.

  Next, a pair of electrodes 6 is formed by printing and drying a silver paste on a roll-shaped thin insulating base material 5 such as a polyester film laminated on the polyester nonwoven fabric 2a. Thereafter, after the polymer resistor 10 is formed by printing and drying the polymer resistor ink so as to overlap the electrode 6, it has adhesiveness with the electrode 6, the polymer resistor 10, and the electrically insulating substrate 5. An adhesive resin layer 8 such as an acrylic adhesive is formed by laminating a covering material 9 formed by laminating a thin electrical insulating overcoat material such as a polyester film, which is formed in advance, thereby completing the heating element body portion. .

  Then, after the outer shape of the heating element main body is removed, the coating material 9 is melted from above the coating material 9 with a soldering iron, and the lead wire 20 is connected with the solder 22. Finally, the lead wire 20 is attached to the attachment portion of the lead wire 20. After applying the insulating protective material 21 such as silicon adhesive, the entire lead wire 20 connecting the terminal member 19 is disposed so as to be covered with another protective member 23 from above the covering material 9 to complete the assembly. .

  The lead wire 20 is connected to the main electrode feeding portion of the main heating portion 2 from the main electrode feeding portion of the right side heating portion 3 and the left side heating portion 4 having the same polarity, respectively. A lead wire 20b connected from the main electrode feeding portion of the main heat generating portion 2 to the power source is connected.

  Here, the terminal member 19 is surface-bonded to the main electrode feeding portion of the main heating portion 2, the right side heating portion 3, and the left side heating portion 4, and the lead wires 20 are connected to the respective terminal members 19, and these leads are connected. The wires are fed from the main electrode feeding portion of the right side heating unit 3 and the left side heating unit 4 to the main electrode feeding portion of the main heating unit 2 through the lead wires 20a respectively having the same polarity. Since the lead wire 20b connected from the portion to the power source is connected, the design in the arrangement of the electrodes 6, 12, 16 and the polymer resistors 7, 13, 17 of the respective planar heating elements is designed. Thus, it is possible to sufficiently bring out the performance of the irregularly shaped planar heating elements, such as by effectively joining the planar heating elements having different shapes.

  That is, by connecting a plurality of polymer resistors 7, 13, and 17 by lead wires 20a and integrating them electrically, each polymer resistor 7, 13, and 17 is adjacent to each other. 13 and 17 electricity can be freely connected in parallel or in series with lead wires without using electrodes printed on an electrically insulating substrate, design constraints are reduced, and electrodes are lengthened. There is no need to worry about voltage drop or reduction of the heat generation area because electricity is supplied to adjacent resistors, and the heating characteristics of the entire sheet heating element can be brought out.

  Moreover, since the strength of the portion connecting the polymer resistors 7, 13, 17 is also constituted by the lead wire 20, it can be remarkably strengthened and the reliability can be improved in terms of durability. Become.

  Since the entire lead wire 20 connecting the terminal members 19 is covered with another protective member 23 from the top of the covering material, the portion connecting the polymer resistors 7, 13, 17 is further provided. In addition to being composed of the lead wire 20 and being protected by the protective member 23, the strength can be remarkably increased, and the reliability can be improved in terms of durability, and the terminal member 19 is connected. Since the lead wire 20 is exposed, it becomes easy to be caught, and there is no fear of damaging the planar heating element, and the productivity and workability of the planar heating element can be improved.

  Further, as shown in FIG. 1, this electrode arrangement pattern is alternately arranged on a plurality of comb-shaped branch electrodes 6d arranged outward from the center of the main electrode located on the inner side. A plurality of comb-shaped branch electrodes 6d disposed inwardly from the outer main electrode 6a positioned so as to surround the main electrode 6b positioned on the inner side from the periphery. Because the main electrode located on the outside where there is a lot of stress from is configured as a closed circuit, even if a part of the electrode located outside becomes cracked or disconnected for some reason, electricity wraps around and is supplied In addition, the sheet heating element can be used without greatly hindering the heat generation of the sheet heating element, and the durability of the sheet heating element can be greatly improved.

  In addition, since the conductive resin material 19a of the terminal member 19 is configured to be thermosetting and thermoadhesive to the electrodes 6, 12, 16, the conductive resin material 19a of the terminal member 19 is the electrode 6, Before being joined to 12, 16, it is in an uncured state and can be bonded by applying heat at the time of surface bonding. When the lead wire 20 is attached, the electrodes 6, 12, 16 are heat bonded. By curing, the volatile matter is removed in the process of thermosetting, so it does not foam, it has a dense structure, sufficient strength can be obtained, and the original adhesive strength of the conductive resin material can be demonstrated. The terminal member 19 can be reliably surface-bonded to the electrode 6 with a simple configuration.

  In addition, since the insulating protection material 21 is applied to the attachment portion of the lead wire 20 and the insulating protection treatment is performed, the electrode 6 and the polymer resistor fed by the electrode 6 from the attachment portion of the lead wire 20 are provided. The body 17 is protected by an insulating protective material and is configured to be cut off from the outside air, thereby preventing problems such as contamination deterioration due to moisture and foreign matter and short-circuiting due to migration of the electrode 6, and more stable performance. Durability can be improved.

  The description of the plurality of planar heating elements such as the bonding of the terminal member 19 has been described with the main heating part 11 as a representative, but this also has the same effect for the other right side heating part 3 and the left side heating part 4. Further, a configuration is obtained in which the electrodes 6, 12a, 16b on one side of the main heat generating portion 2, the right side heat generating portion 3, and the left side heat generating portion 4 are connected by a lead wire 20a to electrically integrate a plurality of heat generating portions. As described above, the electrodes on both sides may be connected by the lead wire 20a, and the configuration of each part may be any configuration as long as the object of the present invention is achieved.

  As described above, according to the present invention, a plurality of polymer resistor electrodes are connected by lead wires, and a plurality of heat generating portions are electrically integrated, so that the electrodes can be arranged effectively and the heat generating body. While maintaining the overall heating characteristics, reliability such as durability can be improved, and the usability is greatly improved. For vehicle heating such as car seat heaters and handle heaters mainly used in vehicles It can also be applied to uses such as appliances and heating appliances.

The top view which shows the structure of the planar heating element in Embodiment 1 of this invention Sectional view of the vicinity of the terminal part of the same heating element (A) Plan view showing the configuration of a conventional heating element (b) Cross-sectional view of the heating element Schematic configuration diagram when pasting a conventional sheet heating element covering material Configuration plan view showing another conventional sheet heating element

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Planar heating element 5 Electrically insulating base material 6 Electrode 7 Polymer resistor 9 Cover material 19 Terminal member 19a Conductive resin material 20 Lead wire 21 Insulating protective material 23 Protective member

Claims (6)

An electrode printed on an electrically insulating substrate, a polymer resistor fed by this electrode, a lead wire feeding power to the feeding portion of the electrode on one side, and a conductive resin material on the other side A terminal member configured to be surface-bonded to the electrode, and a covering material disposed so as to cover the electrode, the terminal member, and the polymer resistor so as to be in close contact with the electrically insulating base material, A plurality of polymer resistors and electrodes are disposed on the substrate, and terminal members are disposed at predetermined positions of the plurality of disposed electrodes, and the respective terminal members are connected to each other by lead wires. Is a sheet heating element in which a polymer resistor is integrated electrically. A plurality of polymer resistors and electrodes are arranged on an electrically insulating substrate, and a terminal member is surface-bonded to a predetermined position of the plurality of arranged electrodes, and the terminal members are connected to each other by lead wires. The planar heating element according to claim 1, wherein the sheet heating element is configured to be electrically integrated, and is configured to cover part or all of the lead wires connecting the terminal members with a protective member different from the covering material. . The planar heating element according to any one of claims 1 to 2, wherein one or both of the electrodes for supplying power to the planar heating element are configured to be a closed circuit. The planar heating element according to any one of claims 1 to 3, wherein the conductive resin material of the terminal member exhibits thermoadhesiveness to the electrode and is thermosetting. The planar heating element according to any one of claims 1 to 4, wherein an insulating protection treatment is applied to a lead wire attachment portion. The heating appliance which mounts the planar heating element of any one of Claims 1-5 as a heat source.