JPH0746628B2 - Positive resistance temperature coefficient heating element - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heating instrument and a positive resistance temperature coefficient heating element used as a general heating device.

2. Description of the Related Art A conventional heating element having a positive temperature coefficient of resistance (hereinafter referred to as PTC) has a structure as shown in, for example, Japanese Patent Publication No. 57-43995 and Japanese Patent Publication No. 55-40161. Between the electrodes
It was self-controlled to an appropriate temperature by the PTC characteristics of the PTC resistor.

However, especially when a high power density is required, it is indispensable to improve the temperature distribution in the direction between the pair of electrodes in order to make the temperature distribution of the heating element itself uniform. As shown in Japanese Patent Laid-Open No. 60-28195 and FIG. 5, there is a configuration in which the distance between a pair of electrodes is close to each other.

In FIG. 5, 1a and 1b are a pair of parallel plate electrodes provided close to each other, and by placing a PTC resistor 2 between them, a high output PTC heating element can be revealed. Became.

Problems to be Solved by the Invention However, when applied to a heating appliance or a general heating device, particularly when control of heat generation amount or heat generation control to each position is required, a plurality of PTC heat generations are required. In addition to complicating the power feeding structure, the body must be individually arranged and power must be fed to each of the bodies, and the portion where the power feeding line is arranged is also large, which has a surface that impairs heat generation performance. Further, in the case of using a plurality of PTC heating elements in this way, it becomes necessary to provide each overheat prevention device individually, which further complicates, and position control in a range smaller than the overheat prevention device cannot be realized. It was

Therefore, the present invention solves the above conventional problems, and provides a positive resistance temperature coefficient heating element that is extremely simple and can control heat generation.

Means for Solving the Problems The technical means of the present invention for solving the above problems is a thin-walled positive temperature coefficient of resistance mainly composed of a composition in which a conductive fine powder is dispersed in a crystalline polymer. A resistor and a pair of electrode bodies provided to apply a voltage in the thickness direction, wherein the pair of electrode bodies are a plurality of strip-shaped electrode bodies formed at appropriate intervals, The projection surfaces in the thickness direction of the resistor are not parallel to each other.

Action The action of this technical means is as follows. That is, the pair of electrode bodies formed on both surfaces of the thin-walled PTC resistor are a plurality of strip-shaped electrode bodies that are formed at appropriate intervals, and are formed on the projection plane in the thickness direction of the resistor. By making it non-parallel, it is possible to change the number of electric power supplied to these multiple electrode bodies and adjust the power supply to the electrode body at the position where you want to generate heat. It is possible to control heat generation and heat generation to each position.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. First, a case where only one side of the pair of electrode bodies is plural will be described.

In Fig. 1, 3 is a PTC resistor having carbon black and polyethylene as main components and a thickness of 0.5 mm.
On the upper surface of the C resistor 3 are three strip-shaped metal plate electrodes 4a, 4b, 4c.
And the metal plate electrode 5 is joined to the lower surface.

With this configuration, the voltage is applied to the electrodes 5 and the electrodes, respectively.
Since it can be applied to 4a, 4b, or 4c, it is possible to freely control the effective heating area or the heating position.

Actually, after covering the insulating film on the PTC heating element having the structure shown in FIG. 1, four PTC heating elements 7 were adhered to the back surface of the heating surface of the panel heater body 6 as shown in FIG. . It was energized at room temperature of 20 ° C. First, when AC100V is applied to all of the electrodes 5 and the electrodes 4a, 4b, 4c, inrush power of 1500W is input, and the temperature of the heating surface of the panel heater main body 6 rises very rapidly, and the power consumption also increases. It decreased and became 520W after about 20 minutes, which was almost stable. The temperature distribution at this time is X- of the panel heater in FIG.
A temperature distribution as shown by I in Fig. 3 was obtained on the heating surface of the X'section, and an epoch-making panel heater excellent in rising performance was realized.

Next, when AC100V is applied to the electrode 5 and the electrodes 4a and 4c, the power is 3
It became stable at 90 W, and the temperature distribution of the panel heater became like II in Fig. 3. Further, when AC100V was applied to the electrode 5 and the electrode 4b, it became almost stable at 270 W, and similarly, the temperature distribution shown in III of FIG. 3 was obtained.

Thus, the amount of heat generation can be easily controlled only by adjusting the presence or absence of energization to the electrodes 4a, 4b, 4c.

In order to realize such heat generation control by on / off control and the like, not only a contact opening / closing function body having a high current capacity is required, but also an obstacle such as noise is generated. At least one is a plurality, and heat generation control is realized with an extremely simple configuration in which only the presence or absence of power supply to the plurality of electrodes is adjusted. Further, when the space of each of the plurality of electrode bodies is small, heat is also generated in the space surface, and this can be taken into consideration to improve the heat generation distribution.

Next, an embodiment in which the resistors of the present invention are configured to be non-parallel to each other on the projection plane in the thickness direction will be described with reference to FIG. Fourth
In the figure, 8 is a PTC resistor having a thickness of 0.5 mm, and strip-shaped metal plate electrodes 9a, 9b, 9c, 9d and 9e are joined to the upper surface of the PTC resistor at regular intervals, and the lower surface of the PTC resistor 8 has an electrode 9a. ~ 9e and the same strip metal plate electrodes 10a, 10b, 10c, 10d, 10e,
10f and 10g were joined at regular intervals. With this configuration, the total number of electrodes is 12, but it is possible to freely control the heat generation in the 35 zones in which the electrodes are orthogonal to each other. For example, if it is desired to heat the portion A of FIG. 4, a voltage may be applied to the electrodes 9b and 10d. Moreover, it is not necessary to install an overheat prevention device in each part due to the PTC characteristics of the PTC resistor. In this way, delicate heat generation control at each position can be realized very easily.

When processing this, for example, one of the pair of electrode bodies and the PTC resistor are continuously bonded and cut into a long piece, and then cut to an appropriate length, and then the direction is changed to the other electrode body. The productivity will be very high if the are continuously bonded. Also, in this case, if the electrode at the end is opened more than 1 mm inside the surface of the PTC resistor, the burr of the electrode cut surface due to cutting, and the risk of contact between different poles due to deformation of the resistor itself, etc. Also, the safety can be dramatically improved.

EFFECTS OF THE INVENTION As described above, the present invention has the following effects.

(1) By configuring a pair of a plurality of strip-shaped electrode bodies to be non-parallel to each other, delicate heat generation control at each position can be realized.

(2) Heat generation can be controlled by adjusting the number of heat-generating parts.

(3) It can be easily processed with a simple structure, has excellent applicability to various devices, and is extremely advantageous in practical use.

[Brief description of drawings]

FIG. 1 is a perspective view of a PTC heating element according to an embodiment of the present invention, and FIG.
FIG. 4 is a front view of a panel heater to which the PTC heating element is applied, FIG. 3 is a heat generation temperature distribution diagram of the panel heater, FIG. 4 is a perspective view of the PTC heating element of the embodiment of the present invention, and FIG. FIG. 3 is a perspective view of the PTC heating element of FIG. 3,8 …… PTC resistor, 4a, 4b, 4c, 5,9a, 9b, 9c, 9d, 9e, 10a, 10
b, 10c, 10d, 10e, 10f, 10g …… electrode, 7 …… PTC heating element.

Claims (2)

[Claims] 1. A thin-walled positive resistance temperature coefficient resistor having a composition in which conductive fine powder is dispersed in a crystalline polymer as a main component, and a voltage-applying element provided in the thickness direction. A pair of electrode bodies, wherein the pair of electrode bodies are a plurality of strip-shaped electrode bodies formed at appropriate intervals, and positive resistances that are non-parallel to each other in a projection plane in the thickness direction of the resistor. Temperature coefficient heating element. 2. The positive resistance temperature coefficient heating element according to claim 1, wherein the positive resistance temperature coefficient resistor has a thickness of 3 mm or less.