JPS60250582A - Heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] This invention relates to a heating element using a positive temperature coefficient thermistor, which is widely used as a smokeless heating device.

[Background technology]

A positive temperature coefficient thermistor is a commonly used thermistor.
In contrast to a star, the resistance value increases as the temperature rises, that is, it has a positive temperature coefficient.

Heating elements (heaters) using this positive temperature coefficient thermistor include PTC ceramic heaters, such as barium titanate (hereinafter abbreviated as titabari), and organic heaters, which are composites of conductive materials such as carbon and organic resins. There is a PTC heater.

PTC ceramic heaters are characterized by: ■ A large range of change in resistance at a set temperature (Curie temperature, hereinafter abbreviated as Tc) arbitrarily determined by the blending ratio of raw materials; ■ Changes in characteristics over time due to use - mainly compared to room temperature. Since the resistance change is small, it has high electrical reliability, making it a useful heating element especially for general household electrical appliances.It also has the advantage of being able to generate heat at a high temperature of approximately 350℃. have. on the other hand,
Disadvantages: Like general ceramics, it is weak against impacts;
■It is not possible to make large-area items with high dimensional accuracy, ■It is not possible to make thin items due to deformation during sintering due to the strength droplets, and ■It is difficult to automatically incorporate machines into products because they are brittle.
The problem is that this increases costs.

Organic PTCs generally consist of a mixture of a conductive material such as carbon and a crystalline thermoplastic resin such as polyethylene or polyvinylidene fluoride. In this case, the bond between the conductive materials is broken due to abnormal expansion when the resin crystals melt due to temperature rise, resulting in an abnormal rise in resistance, and the temperature rise is stopped at a certain temperature. The advantages of organic PTC heaters using this are: ■ Impact resistance;
■It is easy to process (it is flexible and it is possible to make thin heating elements), etc.The disadvantages are: ■The range of change in resistance value with respect to temperature is not very large depending on the resin, ■The heat cycle allows it to be used at room temperature The electrical reliability is inferior to that of a PTC ceramic heater, such as the specific resistance of the heater easily changing over time, and the zero heat generation is as low as about 150°C at most. This was developed in view of the above circumstances, and its purpose is to provide a heating element that has high electrical reliability, shock resistance, and excellent workability.

[Disclosure of the invention]

In order to achieve the above object, the present invention has a plurality of positive characteristic semiconductor porcelain chips each having a cylindrical shape and extending through a resin layer in parallel with each other at appropriate intervals to form a plate-like body. The ends of each chip formed on both sides of the plate-like body are electrically connected to electrode layers provided on both sides of the plate-like body, and the resin layer is penetrated by fluid circulation holes. The gist of the system is the heating element.

That is, this invention makes a positive characteristic semiconductor ceramic chip (hereinafter abbreviated as a chip) with high electrical reliability into a cylindrical shape,
Moreover, by arranging them in parallel in an organic resin layer having fluid circulation holes, we can provide a heating element that is flexible, has good heat conductivity, is easy to process, and can be mass-produced. It's something that makes me happy. This will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the structure of a heating element according to the present invention.

This heating element 1 is constructed in an organic resin layer 3 such that cylindrical chips 2 made of a Chitabari semiconductor or the like are aligned in the axial direction and stand up on the same plane with an appropriate distance between them. from side A to side B.

Penetrating. In the figure, the intervals between the chips are irregular, but they may be regular. In this way, from the A side to the B side of the plate-like body consisting of the chip 2... and the organic resin layer.
Flow holes 4 pass through the surface at appropriate intervals, and serve as flow paths for air, etc. The ends of the chips 2... are exposed on the A side and the B side, and electrode layers 5, 5 are provided in contact with these ends. The electrode layer 5 is provided so as not to block the communication hole 4.

Form an organic resin layer! The resin and material are not particularly limited as long as they have heat resistance according to the operating temperature of the chip, but fluororesins, silicone resins, epoxy resins, phenol resins, polysulfonate resins, and the like are preferable. Also,
If the operating temperature is 100° C. or lower, the U■ curable resin (for example, a spiroacecool type resin such as TB3041 manufactured by Three Pond) is also flexible and cures quickly.

The method for arranging the chips in the organic resin layer may be appropriately selected from press-fitting, botting, etc. in view of the characteristics of the organic resin used. Similarly, the presence or absence of an electrode material and the material forming the Q layer may be appropriately selected in consideration of the adhesion condition with the organic resin used, etc.

A cylindrical positive characteristic semiconductor porcelain chip is made as follows. That is, B a T i 03, T
iO and semiconductor elements (L a ”, P r 3j,
Nd3t, Ga3↑ Y'r,, Nb 5 meetings, sb
MnO2, 5i02, etc. are mixed as a grain boundary control agent, wet-pulverized in a bot mill, and calcined at about 1100°C. Next, it is formed by extrusion molding or direct pressure, and sintered at 135°C. The single Curie point of Ba'l'i03 is arbitrarily selected by performing partial substitution of components. For example, Ba
If PB is substituted for Pb, the temperature will be higher, and if Ba is replaced by Sr, or Ti is replaced by Zn or Sn, the temperature will be lower.

〔Effect of the invention〕

The heating element according to the present invention has a plurality of cylindrical positive characteristic semiconductor porcelain chips, that is, PTC ceramic chips, and is formed into a plate-like material by penetrating through a resin layer having fluid flow holes in parallel with each other at appropriate intervals. Since the ends of each chip formed on both sides of this plate-like body are electrically connected to the electrode layers provided on both sides of the plate-like body,
Compared to conventional heating elements, ■It is flexible against stress such as bending in all directions, and is more impact resistant. ■The distance between the electrodes is uniform, and the surrounding resin layer is evenly distributed. Since heat is removed, current flows mainly around the surface circumference of the chip, and the phenomenon of voltage imbalance does not occur, making it possible to increase the amount of heat generated.

In addition, since it has high electrical reliability and excellent impact resistance, large-area products can be manufactured with high dimensional accuracy, and thin products can be manufactured as well. Therefore, it is possible to obtain a heating element that can be operated at low voltage, such as a battery. Due to its flexibility, mass production can also be improved.

〔reference〕

FIG. 2 shows another example of the heating element. In this example, the cylindrical chips 2 . . . penetrate not only the organic resin 3 but also the metal plate 6 inserted into the organic resin layer in parallel with the electrode layers 5 . The metal plate 6 is inserted to compensate for the fact that the thermal conductivity of organic resin is lower than that of ceramics. The electrode layer 5.5 must have an ohmic connection with the chip 2, which is a positive characteristic ceramic material. Therefore, as shown in Figure 2, chip 2.
The electrode layers 5, 5 may be formed via an electrode material 7 such as an electroless nickel plating layer that makes an ohmic connection with.... As the electrode layer, metal plate, epoxy type,
A silicon-based conductive paste, a metal plate bonded with a conductive paste, etc. are used. The two poles M5, 5 may be used for chip-to-chip connection even in the case of □ in FIG.

The number of electrodes penetrates the organic resin layer 3 in parallel at appropriate intervals, and electrode layers 5, 5 are attached to the upper and lower surfaces, and the plate-shaped heating element 1 is formed. . As shown in Figure 3, if the resin is capable of electroless nickel plating, there is no need to intervene with electrode material for ohmic connection, and the chip 2.
, . . . The nickel plating layer that makes an ohmic connection forms the electrode layer. . In the figure, 8 is a lead wire made of a copper plate or the like, and is attached to the electrode layer with a conductive adhesive 9. The case of FIG. 1 may also be configured in a similar manner.

In addition to nickel plating, the ohmic electrode can be obtained by vapor deposition of aluminum, thermal spraying, rubbing of In-Ga alloy, etc.

Fig. 1 (Al is a perspective view of the essential parts of the embodiment of the heating element according to the present invention, and Fig. 1 (b) is a cross section taken along the I-1 line (a) when an electrode layer is provided. Figure 18) is a sectional view taken along line II- and n when electrodes are provided, and Figure 2 (al) and Figure 2 (b)' are perspective views of another example of the heating element. Figure 3 (al, (bl) is a perspective mark and a cross-sectional view showing another example of a heating element.

1...Heating element 22...Positive characteristic semiconductor porcelain chip 3
...Organic resin layer 4...Flow hole 5...Electrode layer agent Takehiko Matsumoto Patent attorney 9 S/3, 1983 Name of the invention No. 107867, S. 1983
) Matsushita Electric Works Co., Ltd. - Representative Ikumo Kobayashi Agent 6, Specification subject to amendment and drawings 7, Contents of amendment (11 Specification, page 6, lines 13 to 14 [BaTi
03J is corrected to rBacO3J.

(2) rTiOJ on page 6, line 14 of the specification, r
Corrected as Tio2J.

(3) The statement “135°C” on page 6, line 19 of the specification,
r1350℃”.

(4) Figure 3 of the attached drawings is amended as shown in the attached sheet.

Figure 3

Claims (1)

[Claims] (11) A large number of positive characteristic semiconductor porcelain chips are cylindrical and extend parallel to each other at appropriate intervals to form a plate-like body through a resin layer. The heating element has ends of each chip formed on both sides thereof being electrically connected to electrode layers provided on both sides of the plate-like body, and a fluid circulation hole passing through the resin layer. (2) The heating element according to claim 1, wherein the positive characteristic semiconductor porcelain chip is connected to the electrode layer through an electrical material that makes an ohmic connection thereto. (3) The positive characteristic semiconductor porcelain chip 2. The heating element according to claim 1, wherein the chip is directly connected to an electrode layer making an ohmic connection thereto.