JPS58137987A - Heat sensitive panel 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] This invention relates to an Il&thermal surface heating element.

Conventionally, in electric heating devices such as electric carpets, the first
As shown in Figures and Figure 2, 2 temperature sensing electrodes are placed on one side of the #&h Kishima material, such as a polyamide material with negative temperature-impedance characteristics, while a heating line 3 is placed on the other side. 5t of heat-sensitive and heat-generating elements formed by stretching the heat-sensitive resin face material l and covering both sides of the heat-sensitive resin face material l with the insulation films 4,4.
- The temperature control was carried out as follows using a temperature control circuit as shown in FIG.

That is, the tortoise #8 is connected to the heat generation line 3 of the primary heat-sensitive surface heating element 5 via the normally open contact 7m of the power supply relay 7, and the IQ
The oscillation circuit 1ot- is operated by the output voltage VD of the power supply circuit 9 which converts the power supply 8 into a constant voltage DC power supply.
The high frequency voltage ■ outputted from o is divided by the voltage dividing capacitor 11 and applied between the heat-sensitive heat-sensitive surface heating element 5 degree detection pole 21 and the heating line 3 to correspond to the impedance of the heat-sensitive surface heating element 5. The voltage signal is filtered by the filter circuit 12'f.
: and inputs the detected value to the comparison circuit 14 that constitutes the front stage of the next stage switching circuit 13, compares the reference voltage of this comparison circuit 14 with the detected value, and calculates the detected value. When becomes lower than this reference voltage, this comparator circuit 1.4
The transistor 15'j of the subsequent stage of the switching circuit 13, which had been held in the on state flK in the safe temperature range until then, is inverted and the power supply relay 7 connected in series with this transistor 15 is inverted. The excitation dial stops driving, and the normally open contact 7a connected between the IIO power source 8 and the heating line 3 is suddenly reversed from the OFF state to the OFF state, and the power supply path of the heater circuit is opened. It's one thing to cut off.

However, in the structure of one heat-sensitive surface heating element 5, the thickness of the heat-sensitive resin surface material 1 influences the impedance value t-am between the heat generation line 3 and the temperature detection electrode 2, and the heat generation line 3 is There is a problem that the impedance of the heat-sensitive resin surface material l, which generates heat to a high temperature and has a negative temperature-impedance characteristic t*'r in the next state, decreases significantly, resulting in inaccurate grip strength detection. .

In order to avoid such a large drop in the impedance of the heat-sensitive resin surface material l between the heat generating line 3 and the temperature detection electrode 2 at high temperatures, a material with sufficient thickness is adopted as the heat-sensitive resin surface material l in advance. On the other hand, when applied to electric carpets, etc., it is necessary to have appropriate flexibility, so the method of increasing the thickness of the greasy surface material 1 as in the first example is as follows. There is a limit to this, and the disadvantage is that it requires a large amount of material.

Therefore, an object of the present invention is to provide a heat-sensitive surface heating element in which the heating line and the heating conductor can be set sufficiently large without increasing the thickness.

An example of the contribution of Jin's invention is shown in Figures 4 and 5. That is, the heat-sensitive surface heating element 5' includes a heat-generating line 3' made of aluminum foil or the like arranged on one side of a heat-sensitive resin surface material 1' exhibiting a negative temperature-impedance characteristic. On the other side, a comb-shaped temperature detection electrode 2' made of aluminum foil or the like and a comb-shaped short circuit detection electrode 16 are interlocked with each other at a predetermined interval and are distributed evenly over almost the entire area. Furthermore, both sides of this thermosensitive resin surface material 1' are covered with insulating films 4/ and 4/.

This heat-sensitive surface heating element 5' is connected between both terminals 3'a and 3'i of the heat-generating line 3' facing the edge of the heat-sensitive resin surface material 1'. 1
Electrification is applied to generate heat, and the above-mentioned electrode is connected between the terminal 2/a of the tooth-shaped temperature detection electrode 2' facing the edge of the thermosensitive resin surface material 1' and the terminal 3' of the heating line 3'. By applying a high frequency voltage with the circuit configuration shown in Figure 3, the impedance of the thermosensitive resin surface material 1' between both terminals 2'a and 3'a is detected, and the temperature is controlled accordingly. There is.

By the way, the temperature detection electrodes 2' need to be evenly distributed over almost the entire surface of the heat-sensitive surface heating element 5'. This is because if the heat sensitive surface heating element 5' is energized and is locally insulated from the surface, heat will be locally stored in that area and the temperature will rise, which could be dangerous. In order to prevent this, the primary temperature detection electrodes 2' are evenly distributed, so that the local impedance decreases due to local heat accumulation and the impedance ([sum of K11jik can be shut off when the value becomes equivalent to the decrease in impedance when the temperature of the heat-sensitive surface heating element 5' rises uniformly over the entire surface.

In addition, when this type of heat-sensitive surface heating element 5' is used on an electric carpet under equal pressure, there is a possibility that it may be poked from the outside with a metal needle, etc., and furthermore, it may be poked locally with a metal needle or the like from the outside with an iron or the like. There is also a risk of heating. The short-circuit detection electrode 16 is provided for the purpose of detecting and maintaining safety, and if there is a short circuit between the short-circuit detection electrode 16 and the heating line 3' due to the metal needle, etc., or an external If the heat-sensitive material 1' melts when heated with an iron or the like, and a short circuit occurs between the short-circuit detection electrode 16 and the heating line 3', the short-circuit detection circuit 17 detects this as shown in FIG. 6, and the transistor 18 is activated. conducts, thereby cutting off the transistor 15t and stopping the excitation of the relay 7, and the heating line 3
' K is designed to ensure safety by stopping power supply to '. Specifically, a voltage is applied between the short-circuit detection electrode 16 and the heating line 3 by the short-circuit detection circuit 17, and the current flowing due to the first short circuit causes the transistor 18t to conduct and the transistor 15 to be cut off. There is.

For this safe operation, the operation of the temperature control circuit can be used as is between the temperature detection electrode 2 and the heating line 3 described above. That is, when a short circuit occurs, it is equivalent to when the temperature is extremely high with a negative temperature-impedance characteristic, so that the power supply can be cut off.

In this way, in this embodiment, the temperature detection electrode 2' is formed in a comb-teeth shape to reduce the electrode area, so that the temperature detection electrode 2' is reduced in temperature.
11 The impedance value can be increased without increasing the thickness t of the resin face material 1' and without impeding the flexibility. As a result of (7), the signal level for humidity control becomes high, making it possible to accurately detect temperature and improve reliability. Well, since the impedance between the humidity detection electrode 2' and the heating line 3' can be set to a high value under normal conditions, the difference between the signal level in the case of normal temperature control and the signal level in the case of short circuit ◆ In addition, the short-circuit detection electrode 16'' is arranged between the comb teeth of the temperature detection electrode 2', and the difference between the short-circuit detection electrode 16 and the heating line l can be increased. Since the short lI& between them is detected and the current flow to the heating wire w13' is cut off, safety will not be compromised even if the area of the detection electrode 2' is reduced once. Since there are no restrictions on the side where the heat generating line 3' is arranged, the number and shape of the heat generating line 3' can be implemented as usual. It is easier to implement compared to other methods such as providing.

Further, since it is provided on the Km-rated detection electrode 16 on the temperature detection electrode 2' side, etching on this surface requires only a minimum insulation distance, and does not become an impediment during production.

As described above, the heat-sensitive surface heating element of the invention of % B includes a heat-sensitive resin surface material, a heat-generating line uniformly arranged on one side of the heat-sensitive resin surface material, and a heat-generating line uniformly arranged on the other surface of the heat-sensitive resin surface material described in 1. Since it is equipped with a comb-shaped temperature detection electrode that detects the impedance change of the heat-sensitive resin surface material disposed between the heat-generating line and the heat-sensitive resin surface material, the heat-sensitive resin surface material interposed between the heat-generating line and the temperature detection electrode is Impedance can be set sufficiently large, temperature control can be performed with high accuracy without impairing flexibility, and short circuit detection electrodes can be easily formed to ensure safety. .

[Brief explanation of the drawing]

1vA and 2 are respectively a cross-sectional view and a perspective view of a conventional example, FIG. 3 is a diagram WI of a sensibility control circuit of a heat-sensitive surface heating element of the conventional example, and FIGS. A flat Ifi diagram and a sectional view showing the embodiment, and FIG. 6 is a humidity control circuit diagram thereof. 1'...Thermosensitive resin surface material, 2'...Temperature detection electrode, i
'...Fever 4! Road, 4'... Zetsu II & Film, 5
'...Thermosensitive surface heating element Fig. 1 3, Fig. 2 7a Lower 3 Fig. 4 Fig. 5

Claims (1)

[Claims] Heat sensitive resin surface material and this sensitive bear tree 1i1! ii) A comb-shaped temperature sensor for detecting impedance changes in the heat-sensitive resin surface material between the heat-generating lines uniformly arranged on one side of the material and the four heat-generating paths uniformly arranged on the other surface of the heat-sensitive resin surface material. A heat-sensitive surface heating element equipped with an electrode.