JPS6328875Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a heat-sensitive surface heating element used in electric carpets and the like.

In the conventional electric carpet, as shown in FIG.
Switches 3A and 3B are provided for selecting heat generating areas, a cord 4 is pulled out from the cord connecting portion 2, a power plug 5 is attached to the tip of the cord 4, and a temperature control device 6 is provided in the intermediate portion. In this case, the electric carpet main body 1
As shown in the figure, heaters 8 that also serve as heat-sensitive electrodes are provided on regions A and B on one surface of a semiconductor film 7 made of polyamide resin or the like having negative resistance-temperature characteristics, respectively.
At the same time, a heat-sensitive electrode 10 is attached to the entire area of the other side, and a front surface material 13 and a back surface material 14 are applied to both surfaces through insulating layers 11 and 12, respectively.
is pasted.

In terms of the electric circuit, as shown in FIG. 3, this electric carpet has heaters 8 and 9 connected in parallel, which also serve as heat-sensitive electrodes, and are connected to an AC power source (AC100V) 16 via a relay contact 15. Switches 3A and 3B are inserted in series with terminals 8 and 9, respectively, while temperature detection signal output terminal 17
The impedance change of the semiconductor film 7 due to the temperature change of the heat-sensitive electrode heaters 8 and 9 is extracted as a voltage change, and this voltage is sent to the temperature control device 6.
In addition, by controlling the relay contact 15 on and off, the temperature of the heaters 8 and 9, which also serve as heat-sensitive electrodes, is controlled to be constant. In this case, switches 3A and 3B
Areas A and B are switched to the a side, respectively.
Both are in a heat generating state, and by setting one of them to the a side and the other to the b side, one of areas A and B becomes a heat generating state and the other becomes a non-heating state,
By setting both of them to b side, areas A and B
Both are in a non-heating state, and the heating area can be adjusted by operating switches 3A and 3B.

However, such conventional electric carpets
When only one of the heat-sensitive electrode heaters 8 and 9 is energized, that is, only one of the regions A and B is in a heat-generating state; and when both the heat-sensitive electrode heaters 8 and 9 are energized, that is, both regions A and B are in a heat-generating state. Comparing the two, the effective heat-sensitive area of the former is half that of the latter, so the detected impedance of the semiconductor film 7 doubles, and as a result, the temperature control device 6
A problem arose in that the temperature settings were different. In addition, FIG. 4 is an impedance temperature characteristic diagram of the semiconductor film 7, and C ₁ is the heater 8, 9 for the heat-sensitive electrode.
C ₂ shows the characteristics when only one of the heaters 8 and 9 is energized.

Therefore, the purpose of this invention is to provide a heat-sensitive surface heating element that can maintain the same effective heat-sensitive area even if the heat-generating area increases or decreases.

An electric carpet to which an embodiment of this invention is applied will be explained based on FIGS. 5 and 6. In this electric carpet, a heat-sensitive electrode 18 having the same area as the heat-sensitive electrode/heater 9 is attached to area A of one side of the semiconductor film 7 of the electric carpet body 1 in parallel with the heat-sensitive electrode/heater 8, and a heat-sensitive electrode/heater 8 is attached to area B. Attach a heat-sensitive electrode 19 with the same area as 8 and the heater 9 that also serves as a heat-sensitive electrode, and then switch 3.
When switching A and 3B to the a side to make regions A and B into a heat generating state, both heat sensitive electrodes 18 and 19 are disconnected, switch 3A is switched to the b side, and switch 3B is switched to the a side to heat only the region B. When the state is set, the heat-sensitive electrode 19 is connected to one end of the heat-sensitive electrode/heater 9, the heat-sensitive electrode/heater 8 is disconnected, and conversely, the switch 3A is switched to the a side, and the switch 3B is switched to the b side to cover only the area A. The heat sensitive electrode 18 is connected to one end of the heater 8 that also serves as a heat sensitive electrode, and the heat sensitive electrode 19 is separated when the heat generating state is generated. Note that the other configurations are the same as those of the conventional example.

As a result of this configuration, impedance is detected between the heaters 8, 9 and the heat-sensitive electrode 10 when both regions A and B of the electric carpet are in a heat-generating state. Furthermore, when only area A is brought into a heat generating state, impedance is detected between the heater 8 and the heater 8 that also serves as a heat-sensitive electrode, and the heater 8 that serves as a heat-sensitive electrode, and the heat-sensitive electrode 10, and the temperature of the heater 8 that also serves as a heat-sensitive electrode and the heat-sensitive electrode 18 becomes the same. Therefore, the impedance of the semiconductor film 7 at a constant temperature is the same as in the above case. In addition, when only area B is in a heat generating state, the heater 9 that also serves as a heat-sensitive electrode
Since the impedance is detected between the heat-sensitive electrode 19 and the heat-sensitive electrode 10, and the heater 9 that also serves as a heat-sensitive electrode and the heat-sensitive electrode 19 are at the same temperature, the impedance of the semiconductor film 7 is the same as in the above case. . In other words, the effective heat-sensitive area can be made the same when both regions A and B are in a heat-generating state and when only one of regions A and B is in a heat-generating state. The impedance at temperature does not change, so the temperature set by the temperature control device 6 can be the same, so even if the heat generating area of the electric carpet is changed, the temperature can be maintained at the same temperature without operating the temperature control device 6. I can do it.

It goes without saying that the semiconductor film 7 is not limited to one with negative characteristics, but may also be one with positive characteristics.

As described above, the heat-sensitive surface heating element of this invention includes a semiconductor film having resistance-temperature characteristics, and first and second heat-sensitive electrodes attached to the first and second regions of one surface of the semiconductor film, respectively. a heater, a first heat-sensitive electrode having the same area as the first heat-sensitive electrode heater and attached to a second region on one surface of the semiconductor film in parallel with the second heat-sensitive electrode heater; A second heat-sensitive electrode having the same area as the second heat-sensitive electrode/heater and attached to a first region on one side of the semiconductor film in parallel with the first heat-sensitive electrode/heater, and a second heat-sensitive electrode on the other side of the semiconductor film. The third heat-sensitive electrode attached to the entire area and the first heat-sensitive electrode-cum-heater are connected to each other, and when disconnected, the first heat-sensitive electrode is connected to one end of the second heat-sensitive electrode-cum-heater. a second switch that connects the second thermal electrode to one end of the first thermal electrode heater when disconnected; and a second switch that connects the second thermal electrode to one end of the first thermal electrode heater when disconnected. This has the effect that even if the heat generating area is increased or decreased by operating the first and second switches, the effective heat sensitive area can be kept the same.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional electric carpet, Figure 2 is a perspective view of a conventional electric carpet;
Figure 3 is a cross-sectional view of the main part, Figure 3 is its electric circuit diagram, Figure 4 is an impedance temperature characteristic diagram to explain its drawbacks, and Figure 5 is an electric circuit diagram to which an embodiment of this invention is applied. The electric circuit diagram of the carpet, FIG. 6 is a sectional view of the electric carpet of the same embodiment. 3A, 3B... Switch, 7... Semiconductor film, 8, 9... Heat sensitive electrode heater, 10, 1
8,19...Heat-sensitive electrode.

Claims (1)

[Scope of utility model registration request] A semiconductor film having resistance-temperature characteristics, first and second heat-sensitive electrode heaters attached to first and second regions of one surface of the semiconductor film, and having the same area as the first heat-sensitive electrode heater. and a first heat-sensitive electrode attached to a second region of one surface of the semiconductor film in parallel with the second heat-sensitive electrode/heater, and the semiconductor film having the same area as the second heat-sensitive electrode/heater. a second heat-sensitive electrode attached to a first area of one side of the film in parallel with the first heat-sensitive electrode/heater; a third heat-sensitive electrode attached to the entire area of the other side of the semiconductor film; a first switch that connects the first heat-sensitive electrode to one end of the second heat-sensitive electrode-cum-heater when disconnected, and a switch that connects the first heat-sensitive electrode to one end of the second heat-sensitive electrode-cum-heater; 1. A heat-sensitive surface heating element, comprising: a second switch that connects the second heat-sensitive electrode to one end of the heater for the first heat-sensitive electrode when the current supply path to the heater is disconnected;