JP2013088108A - Planar heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a planar heater capable of providing a comfortable warm feeling regardless of a moisture absorption state of a heating element.SOLUTION: This planar heater includes a quick heating control means 16 for controlling the heating element 11 at a target temperature higher than a temperature set by a temperature setting means 13 in starting power distribution, a Low forced start control means 18 for controlling the heating element to start with a power distribution rate higher than that of the quick heating control means, a determining means 17 for determining whether the Low forced start control means can be implemented or not, a moisture absorption determining means 20 for determining a moisture absorbing state of the heating element from a power distribution state of the heating element under the Low forced start control, and a Hi forced start control means 19 for controlling the heating element to start with a power distribution rate further higher than that of the Low forced start control means, only when the moisture absorption of the heating element is determined by the moisture absorption determining means, thus the comfortable warm feeling can be provided regardless of the existence or non-existence of the moisture absorption of the heating element.

Description

  The present invention relates to a sheet heating device such as an electric carpet, an electric blanket, and floor heating.

  Conventionally, a heating element having a one-wire structure in which a heating wire and a temperature detection wire are used as one temperature-sensitive heater wire is often used for this type of planar warming tool. When the one-wire configuration is adopted, it is not necessary to separately wire the heat generation wire and the temperature detection wire, and the temperature can be controlled only by wiring a single temperature-sensitive heater wire.

  Further, since the heat generating portion and the temperature detecting portion are integrated, the temperature of the heat generating wire can be directly detected, so that the temperature rise can be suppressed even when the local heat is maintained, and the safety is high.

  The temperature-sensitive heater wire used in the one-wire configuration has a polymer temperature sensor interposed between the heating line and the temperature detection line, and the current flowing between the lines varies depending on the temperature characteristics of the impedance of the temperature sensor. Therefore, it is a common control method to perform temperature control by taking this out from the temperature detection line.

  Therefore, as shown in FIG. 8, the conventional planar warmer has a heating element 1 that is a one-line temperature-sensitive heater wire disposed in a planar warming tool (not shown), and the temperature of the heating element 1. Temperature detection means 2 to detect, temperature setting means 3 to set the control temperature of the surface heating device, detection value (detected temperature of the heating element 1) detected by the temperature detection means 2 and temperature setting means 3 The control means 4 which controls electricity supply to the heat generating body 1 from the set temperature thus set.

  Here, the relationship between the detection value of the temperature detection means 2 and the actual temperature of the heating element 1 is shown in FIG. When the heating element 1 is energized, the detection value of the temperature detection means 2 decreases as the temperature of the heating element 1 rises.

  On the other hand, when the user changes the temperature to be set by the temperature setting means 3 such as VR, and the detected value of the temperature detecting means 2 decreases to a signal level (V1) corresponding to the set temperature set in the temperature setting means 3. In the control means 4, temperature control is performed so that the energization of the heating element 1 is not energized.

  In addition, at the start of use of the surface warmer, it is easily considered that the temperature of the surface warmer has decreased to a low temperature depending on the use environment. In this case, the user sets the temperature with the temperature setting means 3. When the temperature of the heating element 1 starts to be controlled at the set temperature, the temperature rise of the surface warming tool becomes slow and uncomfortable for the user. As shown in FIG. The heating element 1 is controlled so that the set temperature is higher than the set temperature for a certain time from the time, and a control method (rapid heat control method) for increasing the temperature quickly is employed (for example, see Patent Document 1).

  In the conventional configuration, if the temperature sensor used in the one-wire heater wire is not used for a long period of time or absorbs moisture due to environmental conditions, the impedance is reduced, and the temperature between the heating wire and the temperature detection wire is reduced. The flowing current increases.

  FIG. 11 shows the relationship between the temperature of the heating element and the detected value of the temperature detecting means when the moisture-absorbing heating element and the dry heating element are compared.

As is apparent from FIG. 11, even when the detected value of the temperature detecting means is the same value, the temperature TA of the heat-absorbing heating element and the temperature TB of the drying heating element are TA> TB
Thus, even if the detected value of the temperature detecting means is the same value, the actual surface temperature of the heating element is lower in the hygroscopic state than in the dry state.

  From this, in the case of a heat-generating body in a hygroscopic state, the temperature control is performed based on the detection value of the temperature detection means in spite of the low temperature of the heat-generating body. The actual surface temperature of the heating element is lowered, which causes discomfort to the user.

  In particular, the symptom is likely to appear immediately after purchase or at the beginning of the season because the temperature sensing body often absorbs moisture.

  In order to solve the above problems, the conventional surface heating device is provided with a forced start-up control means for starting up the heating element at a set temperature higher than the set temperature by the temperature setting means for a certain time from the start of energization. Yes. (For example, refer to Patent Document 2).

  As a result, the temperature is controlled from the beginning of energization to a higher temperature, and the temperature of the heating element rises compared to the conventional one. The temperature characteristics were recovered and a comfortable warm feeling could be given.

JP-A-6-102944 Japanese Patent No. 4609214

  However, in the above-described conventional configuration, forced start-up control is performed at a high temperature at the start of energization regardless of whether the heating element absorbs moisture or not. Therefore, if moisture absorption is not performed, the surface temperature becomes too hot and the user feels uncomfortable. Had the problem of giving. Moreover, even if the target temperature during forced start-up control is not absorbed, if it is lowered so as not to be unsafe and uncomfortable, there is a problem that sufficient effects cannot be obtained when the original moisture is absorbed. It was.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a planar warming tool that can always give a comfortable warm feeling regardless of whether or not a heating element absorbs moisture.

In order to solve the above-described conventional problems, a planar warming device of the present invention is connected to a heating element in which a heating wire and a temperature detection wire arranged in a planar warming device body are integrated, and the heating device. And a controller,
The controller is
Temperature detecting means for detecting the temperature of the heating element;
Temperature setting means for setting a control temperature of the heating element;
Quick heat control means for starting up and controlling the heating element at a target temperature higher than the set temperature by the temperature setting means at the start of energization;
Low forced start-up control means for controlling the start-up of the heating element at an energization rate higher than that of the rapid heat control means;
Determination means for determining whether or not the Low forced startup control means can be implemented;
Moisture absorption determining means for determining the moisture absorption state of the heating element from the energized state of the heating element during the startup control of the Low forced startup control means;
Only when the heating element is determined to be absorbing moisture by the moisture absorption determination means, Hi forced startup control that controls the startup of the heating element at a higher energization rate than the energization rate of the Low forced startup control means. Means. Thus, only when it is determined that the heating element has absorbed moisture, the energization control is performed by the Hi forced startup control unit that controls the startup of the heating element at a higher energization rate than the energization rate of the Low forced startup control unit. Therefore, when the moisture is absorbed, the temperature of the heating element can be raised to an appropriate temperature without being controlled so that the heating element can be easily removed during the temperature raising control. Can restore normal temperature characteristics and give a comfortable warm feeling. In addition, when there is no moisture absorption, the startup control is performed by the Low forced startup control instead of the Hi forced startup control, and the energizing rate is inadvertently raised and the surface temperature becomes too hot, giving the user an uncomfortable feeling. There is no, can give a comfortable warm feeling.

  In this case, the Low forced start-up control means for controlling the start-up of the heat generating element at an energization rate higher than the power supply rate of the rapid heat control means is energization when the start-up control is performed while energization is repeatedly turned on / off. By shortening the turn-off time shorter than that of the quick heat control means, a high energization rate can be obtained, the temperature can be raised quickly, and the set temperature can be reached quickly.

  Furthermore, only when it is determined by the moisture absorption determining means that the heating element is absorbing moisture, the Hi forced startup control means that controls the startup of the heating element at a higher energization rate than the energization rate of the Low forced startup control means. When the moisture is absorbed, the heating element can be heated to an appropriate temperature without being controlled so that the surface temperature of the heating element is lowered. This makes it easier to restore normal temperature characteristics at an early stage and gives a comfortable warm feeling. In addition, when there is no moisture absorption, the startup control is performed by the Low forced startup control instead of the Hi forced startup control, and the energizing rate is inadvertently raised and the surface temperature becomes too hot, giving the user an uncomfortable feeling. There is no, can give a comfortable warm feeling.

  The planar warming tool of the present invention can always give a comfortable warm feeling regardless of whether the heating element absorbs moisture or not.

Control block diagram of planar warming tool in Embodiment 1 of the present invention The schematic diagram which shows the relationship between the time from the time of an energization start in Embodiment 1 of this invention, and control target temperature Schematic showing the relationship between the heater wire temperature and the surface temperature when the energization rate during start-up control is low in Embodiment 1 of the present invention Schematic diagram showing the relationship between heater wire temperature and surface temperature when the energization rate is high during start-up control in Embodiment 1 of the present invention The chart showing the heating element detection temperature and the heating element surface temperature when moisture is absorbed and when moisture is not absorbed in Embodiment 2 of the present invention Control block diagram of planar warming tool in Embodiment 3 of the present invention The chart showing the heating element detection temperature and heating element surface temperature at different power supply voltages in Embodiment 4 of the present invention Control block diagram of a conventional surface heating device A diagram showing the relationship between the detection value of the temperature detection means and the temperature of the heating element A diagram showing the relationship between the temperature and time of the surface heating device at the start of energization Diagram showing the difference between the dry state and moisture absorption state of the heating element

A first invention includes a heating element in which a heating wire and a temperature detection wire arranged in a planar warming tool body are integrated, and a controller connected to the heating body, the controller comprising:
Temperature detecting means for detecting the temperature of the heating element;
Temperature setting means for setting a control temperature of the heating element;
Quick heat control means for starting up and controlling the heating element at a target temperature higher than the set temperature by the temperature setting means at the start of energization;
Low forced start-up control means for controlling the start-up of the heating element at an energization rate higher than that of the rapid heat control means;
Determination means for determining whether or not the Low forced startup control means can be implemented;
Moisture absorption determining means for determining the moisture absorption state of the heating element from the energized state of the heating element during the startup control of the Low forced startup control means;
Only when the heating element is determined to be absorbing moisture by the moisture absorption determination means, Hi forced startup control that controls the startup of the heating element at a higher energization rate than the energization rate of the Low forced startup control means. Means,
When the heating element absorbs moisture, it becomes easier to remove the moisture from the heating element than before, and normal temperature characteristics can be restored early, giving a comfortable warm feeling. it can. Even when the heating element does not absorb moisture, the energization rate is inadvertently increased, the surface temperature becomes too high, and the user is not uncomfortable and a comfortable warm feeling can be given.

  In particular, the second aspect of the invention includes the time determination means and the counting means for measuring the number of times the heating element is turned on / off within a predetermined time from the start of energization, and the moisture absorption determining means of the first invention. When the number of energization on / off times of the heating element is greater than or equal to a predetermined number, it is possible to determine moisture absorption of the heating element by adopting a configuration in which moisture absorption is determined. As apparent from the prior art, when the heating element absorbs moisture, the actual temperature of the heating element is lower in the moisture-absorbing heating element than in the dry condition even if the detected value of the temperature detecting means is the same value. As described above, since the temperature control is performed based on the detection value of the temperature detection means even when the temperature of the heating element is low, the number of times of energization on / off within a certain time increases when the heating element absorbs moisture. Therefore, it is possible to determine moisture absorption of the heating element from the number of energization on / off of the heating element within a certain time from the start of energization.

  In a third aspect of the invention, in particular, in the first or second aspect of the invention, the determination means includes an internal temperature detection means for detecting the temperature inside the controller, and the internal temperature detected by the internal temperature detection means is less than a predetermined temperature. And, when the set temperature of the temperature setting means is equal to or higher than a predetermined level, the control is performed by the Low forced startup control, and the moisture absorption determining means is configured to perform the moisture absorption determination only during the Low forced startup control. If the temperature of the heating element is high immediately after energization or the like, the temperature control by the Low forced startup control means and the Hi forced startup control means and the moisture absorption determination are not performed, thereby preventing the temperature from being inadvertently increased. And the accuracy of moisture absorption determination can be increased.

  In a fourth aspect of the invention, in particular, in any one of the first to third aspects of the invention, the moisture absorption determination unit includes a voltage detection unit that detects a voltage applied to the heating element, and absorbs moisture by a detection voltage of the voltage detection unit. By adopting a configuration in which the determination value of the determination is changed, the accuracy of moisture absorption determination can be further increased.

  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)
FIG. 1 is a control block diagram of the sheet heating device in the first embodiment of the present invention, and FIG. 2 is a diagram comparing temperatures of Hi forced startup control, Low forced startup control, and rapid thermal control. It is.

  In FIG. 1, a heating element 11 is a one-wire heater line in which a heating line and a temperature detection line are integrated. There is a controller 15 connected to the heating element 11, and the temperature detection means 12 is a temperature of the heating element 11. The temperature setting means 13 can be arbitrarily switched to a predetermined set temperature such as a slide volume by the user, and the quick heat control means 16 sets the temperature at the start of energization. The temperature of the heating element 11 is raised and controlled at a target temperature higher than the set temperature of the means 13, and the determination means 17 is a means for determining whether or not the Low forced startup control means 18 can be implemented. The start-up control unit 18 controls the start-up of the temperature of the heating element 11 at a higher energization rate than the quick heat control unit 16 when the determination unit 17 satisfies a predetermined condition.

  The Hi forced startup control means 19 controls the startup of the temperature of the heating element 11 at an energization rate higher than the energization rate of the Low forced startup control means 18, and the moisture absorption determination means 20 Only when the moisture absorption state of the heating element 11 is determined from the energized state of the heating element 11 during the startup control of the raising control means 18 and it is determined that the heating element 11 is absorbing moisture, the startup control by the Hi forced startup control means 19 is performed. It is the structure to do. The moisture absorption determination method of the moisture absorption determination means 20 will be described later.

  About the planar warming tool comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  In order to quickly reach the set temperature set by the temperature setting means 13 by the user, the planar warming tool has a target temperature higher than the set temperature set by the user at the start of energization in the fast heat control means 16. Generally, the heating element 11 is energized and controlled at a set temperature after a certain time.

  However, as described above, immediately after purchase or at the beginning of the season, since the surface heating device, particularly the heating element 11, absorbs moisture, the relationship between the detected value of the temperature detecting means 12 and the temperature of the heating element 11 changes. The temperature may not be controlled at the set temperature intended by the user.

  Here, if control is to be performed at the original control temperature, it is necessary to quickly remove moisture and return the relationship between the detected value of the temperature detection means 12 and the temperature of the heating element 11 to a normal state.

  Therefore, as shown in FIG. 2, not only the rapid heat control for advancing the time to reach the set temperature, but also the low forcing to start up and control the heating element 11 at a current rate higher than the current rate of the rapid heat control means 16. By controlling the energization of the heating element 11 with the energization rate higher than the rapid heating temperature by the rapid heating control means 16 by the start-up control means 18, the temperature of the heating element 11 can be increased more quickly. 11 makes it easy to remove moisture.

  In the start-up control, in FIG. 2, the temperature rise of the heating element 11 is displayed as a straight line for convenience, but in actuality, the start-up control is performed while energization of the heating element 11 is repeated, and the temperature rises and fallss. The temperature is raised while repeating. FIG. 3 is a schematic diagram showing the relationship between the heater wire temperature of the heater, which is the heating element 11, the surface temperature of the planar warming tool, and the energization on / off state of the heater.

  As shown in FIG. 3, when the heater that is the heating element 11 is energized and the heater line temperature rises and the heater line temperature reaches the target temperature, the energization to the heater is stopped for a certain period of time. When the heater is turned on again and the heater wire temperature reaches the target temperature, the heater is turned off for a certain period of time.

Thus, the surface temperature of the heater approaches the set temperature while energization is repeatedly turned on / off. The time ratio of the energization ON time T1 with respect to the total time of the energization ON time T1 and the energization OFF time T2 is the energization rate. By increasing the energization rate as shown in FIG. The surface temperature can be quickly reached the set temperature.

  The moisture absorption determining means 20 in FIG. 1 determines the moisture absorption state of the heating element from the energized state of the heating element 11 of the Low forced startup control means 18. Details of the determination method will be described in a second embodiment.

  Only when it is determined by the moisture absorption determining means 20 that the heating element 11 is absorbing moisture, Hi forced start-up control is performed so that the heating element 11 is energized and controlled at a higher energization rate in the route of FIG. The startup control of the means 19 is switched.

  As described above, in the present embodiment, during the startup control of the Low forced startup control means 18, it is determined whether or not the heating element 11 is absorbing moisture by the moisture absorption determination means 20, and the heating element 11 absorbs moisture. Only when the heat generating element 11 is controlled to increase the temperature of the heating element 11 at an energization rate higher than the energization rate of the Low forced start-up control means 18, Moisture can be easily removed, normal temperature characteristics can be restored early, and a comfortable warm sensation can be provided. Then, when there is no moisture absorption by the heating element 11, the start-up control by the Low forced start-up control means 18 is continued and does not switch to the start-up control by the Hi forced start-up control means 19, so carelessly energizing By increasing the rate, the surface temperature becomes too hot and the user is not discomforted, and a comfortable warm feeling can be given.

  In this case, the Low forced start-up control means 18 for starting and controlling the heating element 11 at an energization rate higher than the energization rate of the rapid heat control means 16 is controlled to start up while the heating element 11 is repeatedly turned on / off. By shortening the time for turning off the power when the heating is performed, the energization rate is increased by making the time shorter than that of the quick heat control means 16, and the surface temperature of the surface heating device can be quickly increased and the set temperature can be reached quickly.

  Furthermore, only when it is determined by the moisture absorption determining means 20 that the heating element 11 is absorbing moisture, the Hi forced startup that controls the startup of the heating element 11 at an energization rate higher than that of the Low forced startup control means 18. By providing the raising control means 19, it is possible to raise the temperature to an appropriate temperature without controlling the surface temperature of the heating element 11 to be low when moisture is absorbed, and in addition, heat is generated during the temperature raising control. Moisture removal from the body 11 is facilitated, normal temperature characteristics can be restored early, and a comfortable warm sensation can be provided. In addition, when there is no moisture absorption, the startup control is performed by the Low forced startup control instead of the Hi forced startup control, and the energizing rate is inadvertently raised and the surface temperature becomes too hot, giving the user an uncomfortable feeling. There is no, can give a comfortable warm feeling.

  The energization rate of the Low forced start-up control means 18 and the energization rate of the Hi forced start-up control means 19 are specifically the T2 which is the energization OFF time shown in FIGS. This can be realized by setting such as 60 seconds for the control means 18 and 30 seconds for the Hi forced start-up control means 19. By the way, in an example in the case where the startup control is performed by the rapid heating control in the conventional surface heating device, the heater ON time T1 is about 3 minutes and the heater OFF time is about 1 minute. .

(Embodiment 2)
FIG. 5 shows the surface temperature of the heating element when the heating element 11 absorbs moisture and the value when the heating element 11 does not absorb moisture, and the detected value at the temperature detecting means 12 (detection temperature of the heating element). It is the chart which showed. The left side of FIG. 5 is a chart with no moisture absorption, and the right side is a chart with moisture absorption. In the chart of FIG. 5, the temperature repeatedly increases and decreases because the energization is repeatedly turned on / off depending on the detection value by the temperature detecting means 12.

  As described in Patent Document 2 which is a prior art, when the temperature sensing body absorbs moisture between the heating wire and the temperature detection wire used in the one-wire heater wire, the impedance of the temperature sensing body decreases. The current flowing between the heat generation line and the temperature detection line increases.

  The one-wire heater wire, which is the heating element 11, originally has a characteristic that the impedance of the temperature sensing element decreases as the temperature of the temperature sensing element increases, and the current flowing between the heating line and the temperature detection line increases. Utilizing this, a change in current caused by a change in impedance of the temperature sensing element is converted into a DC voltage by the temperature detecting means 12, and the temperature of the heating element 11 is detected. However, since the impedance of the temperature sensing element is reduced not only by the temperature rise but also by moisture absorption as described above, if the heating element 11 is in the moisture absorbing state, the heat generating body 11 generates heat as shown in the chart with moisture absorption on the right side of FIG. Although the surface temperature of the body 11 is low, it is determined that the detected temperature of the heating element 11 detected by the temperature detecting means 12 has reached the control target temperature, and the power supply to the heating element 11 is turned off. 11 is turned on / off more frequently.

  Accordingly, the moisture absorption determining means 20 has a time measuring means and a counting means for measuring the number of times the heating element is turned on / off within a predetermined time from the start of energization. When the number of on / off times is equal to or greater than the predetermined number, it is possible to determine moisture absorption of the heating element 11 by adopting a configuration for determining moisture absorption. The determination time and the determination value vary depending on the temperature characteristics of the heating element 11. In the embodiment, it is determined that moisture has been absorbed when the number of energizations on / off five times or more within 20 minutes is counted.

(Embodiment 3)
FIG. 6 is a control block diagram of the planar warming tool according to the third embodiment of the present invention.

  The internal temperature detection means 23 detects the internal temperature of the controller 15, and since the controller 15 is connected to the heating element 11, when the heating element 11 is energized, the influence of the temperature of the heating element 11 is affected. In response, the temperature inside the controller 15 rises.

  Using this temperature change, the determination means 17 determines that the set temperature set by the user in the temperature setting means 13 is equal to or higher than a predetermined level, and the temperature inside the controller 15 detected by the internal temperature detection means 23 is the predetermined temperature. The forced low rise control by the forced low rise control means 18 is performed only when the temperature is low, for example, when the temperature is low, for example, less than 20 ° C.

  Further, in other cases, that is, when the set temperature set by the user is lower than a predetermined level, for example, when the scale is low, or when the detected temperature of the internal temperature detecting means 23 is high immediately after energization or the like, the Low forced on Only the rapid heat control by the rapid heat control means 16 is performed without performing the control by the raising control means 18.

  Further, the moisture absorption determining means 20 performs the moisture absorption determination only when the Low forced startup control means 18 is performing Low forced startup control. Moisture absorption is determined by turning on / off the heating element 11 within a certain time from the start of energization. Therefore, when the surface temperature is sufficiently warm, such as when the surface heating device is reused immediately after the previous use, Cannot judge. Therefore, the moisture absorption determination is performed only when the temperature inside the controller 15 detected by the internal temperature detecting means 23 is lower than a predetermined temperature. Thereby, the moisture absorption determination with high accuracy can be performed.

  The determination condition of the determination unit 17 is determined in consideration of merchantability, usability, and the like, and is not limited to the numerical values described here.

(Embodiment 4)
FIG. 7 is a chart showing the relationship between the heating element detection temperature and the heating element surface temperature at the time of different power supply voltages in the planar warming device in the fourth embodiment of the present invention. In the example in the present embodiment, a power supply voltage is applied to the heating element 11. The left side of FIG. 7 is a chart when the power supply voltage is 100V, and the right side is when the power supply voltage is 115V. In the chart of FIG. 7, the temperature repeatedly increases and decreases because the energization on / off is repeated according to the detection value by the temperature detection means 12.

  As can be seen from FIG. 7, even when the moisture absorption state is the same, when the voltage applied to the heating element 11 is changed, the control state of the heating element 11 changes. When the voltage is increased, the time until the predetermined control temperature is reached is shortened, and the number of times the heating element 11 is turned on / off within a certain time is increased.

  Even if the power supply voltage varies depending on the power supply situation at the installation location, in the example of the fourth embodiment of the present invention, voltage detection means 24 is provided to correctly determine moisture absorption, and the voltage applied to the heating element 11 Is detected. The moisture absorption determination unit 20 changes the determination value of the moisture absorption determination according to the detection voltage of the voltage detection unit 24. For example, when the power supply voltage is increased, the number of times the heating element 11 is turned on / off within a predetermined time increases. Therefore, the comparison value of the number of times of turning on / off the heating element 11 determined as moisture absorption is increased above the reference determination value. ing. Thereby, a more accurate moisture absorption determination can be performed.

  As described above, the surface heating device according to the present invention can detect the moisture absorption state of the one-wire heater wire and realize safe and comfortable temperature control, and thus is applied to a device using a temperature-sensitive heating element. it can.

DESCRIPTION OF SYMBOLS 11 Heat generating body 12 Temperature detection means 13 Temperature setting means 15 Controller 16 Rapid heat control means 17 Determination means 18 Low forced start-up control means 19 Hi forced start-up control means 20 Hygroscopic determination means 23 Internal temperature detection means 24 Voltage detection means

Claims (4)

A heating element in which a heating wire and a temperature detection wire arranged in the surface warmer body are integrated;
A controller connected to the heating element,
The controller is
Temperature detecting means for detecting the temperature of the heating element;
Temperature setting means for setting a control temperature of the heating element;
Quick heat control means for starting up and controlling the heating element at a target temperature higher than the set temperature by the temperature setting means at the start of energization;
Low forced start-up control means for controlling the start-up of the heating element at an energization rate higher than that of the rapid heat control means;
Determination means for determining whether or not the Low forced startup control means can be implemented;
Moisture absorption determining means for determining the moisture absorption state of the heating element from the energized state of the heating element during the startup control of the Low forced startup control means;
Only when the heating element is determined to be absorbing moisture by the moisture absorption determining means, the Hi forced startup control that controls the startup of the heating element at a target temperature higher than the energization rate of the Low forced startup control means. Means,
A surface heating device equipped with. The moisture absorption determining means has a time measuring means and a counting means for measuring the number of times the heating element is energized on / off within a predetermined time from the start of energization, and the number of times the heating element is energized on / off within a certain time from the start of energization. The planar warming tool according to claim 1, wherein if it is equal to or more than a predetermined number of times, it is determined that the moisture is absorbed. The determination means includes an internal temperature detection means for detecting the temperature inside the controller, the internal temperature detected by the internal temperature detection means is less than a predetermined temperature, and the set temperature of the temperature setting means is equal to or higher than a predetermined level. The start-up control is performed by the Low forced start-up control means, and the moisture absorption determining means performs the moisture absorption determination only during the start-up control by the Low forced start-up means. 2. A surface heating device according to 2. The said moisture absorption determination means is provided with the voltage detection means which detects the voltage applied to the said heat generating body, and changes the determination value of moisture absorption determination with the detection voltage of the said voltage detection means, The 1-3 characterized by the above-mentioned. The surface heating tool according to any one of the above.