JP3956780B2

JP3956780B2 - Surface heating device

Info

Publication number: JP3956780B2
Application number: JP2002176861A
Authority: JP
Inventors: 雅徳西川; 尚保片山
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2002-06-18
Filing date: 2002-06-18
Publication date: 2007-08-08
Anticipated expiration: 2022-06-18
Also published as: JP2004020084A

Description

【０００１】
【発明の属する技術分野】
本発明は、電気カーペットや電気毛布、床暖房等の面状採暖具に関するものである。
【０００２】
【従来の技術】
従来、この種の面状採暖具は、例えば図６に示すように、面状採暖具本体（図示せず）に半面ずつ配設されたヒータＡ１と温度検知線Ａ２、及びヒータＢ３と温度検知線Ｂ４は、それぞれ温度によりインピーダンスが変化する感温材Ａ５及び感温材Ｂ６をはさんで感温ヒータ線Ａ７及び感温ヒータ線Ｂ８を構成している。以降、採暖具を２分割し、一方をＡ面、他方をＢ面と呼ぶ。
【０００３】
ヒータＡ１の発熱により、面状採暖具の温度が変化すると、感温材Ａ５のインピーダンスが変化し、温度検知線Ａ２からヒータＡ１へ流れる電流が変化する。また、Ｂ面側もＡ面側と同様に温度検知線Ｂ４からヒータＢ３へ流れる電流が変化する。
【０００４】
この電流変化を電圧信号として取り出して温度検出を行うが、それぞれ独立して温度検出を行うと、温度検出回路の部品点数が多くなり、コストも高くなるためそれぞれの温度検知線に流れる電流を合成し、電圧信号として取り出すことで、一つの平均温度検出手段９にて平均温度検出を行っている。ここで、平均温度検出手段９の検出値とヒータ温度との関係を図７に示す。ヒータＡ１に通電を行う通電手段Ａ１０もしくはヒータＢ３に通電を行う通電手段Ｂ１１が通電状態のときには、ヒータ温度の上昇につれ感温材Ａ５もしくは感温材Ｂ６のインピーダンスが小さくなるため、流れる電流が大きくなる。一方、平均温度検出手段９の検出値（電圧）は図に示すように温度が高くなるにつれて小さくなり、ヒータへの通電が非通電のとき最大値（Ｖ０）になるように回路構成している。この検出値が使用者の設定した温度に相当する信号レベルまで低下したときに、温度制御手段１２において、通電手段を非通電状態とするような温度制御を行っていた。
【０００５】
ここで、通電手段が非通電状態のときには電流が流れないため、Ａ面及びＢ面のどちらの通電手段も通電状態のとき（全面通電）と、片側のみの通電手段が通電状態のとき（半面通電）とでは、ヒータが同じ温度でも流れる電流が異なることになる。このことから、全面通電のときと半面通電とで、ヒータ温度に対する平均温度検出手段９の検出値の関係が異なることになる。従って、この検出値と比較しヒータをオンするかオフするかを判定するための判定レベルを、判定レベル切替手段１３によって、全面通電のときは全面用の判定レベル（Ｖ１）、半面通電のときは半面用の判定レベル（Ｖ２）とに切り替えて、その判定レベルに基づいて温度制御手段１２にて温度制御を行っていた。
【０００６】
【発明が解決しようとする課題】
しかしながら、前記従来の構成では、全面通電であるにもかかわらず、片側の通電手段、例えば通電手段Ａ１０が通電できなくなるような故障が発生したときに、図８のように、半面用の判定レベル（Ｖ２）ではなく、全面用の判定レベル（Ｖ１）で温度制御が行われるため、平均温度検出手段９の検出値が半面用の判定レベル（Ｖ２）を下回っても通電を続け、故障していない側の通電手段Ｂ１１の通電時間Ｔ１が、通電手段が正常なときの通電時間Ｔ２よりも長くなり、ヒータＢ３の温度が本来の設定温度よりも遙かに高い温度で制御することになることから、使用者に、故障していない側は熱すぎる、故障している側はぬるすぎるといった不快感を与えるような構成となっていた。
【０００７】
本発明は、前記従来の課題を解決するもので、片側の通電手段の故障を検知し、使用者に不快感を与えないことを目的とするものである。
【０００８】
【課題を解決するための手段】
前記従来の課題を解決するために、面状採暖具本体に半面ずつ配設されたヒータと、各ヒータ温度の平均温度を検出する平均温度検出手段と、各ヒータへ通電を行う通電手段と、前記複数のヒータのうち、幾つのヒータを通電状態にするかにより判定レベルを切り替える判定レベル切替手段と、平均温度検出手段の検出値の変化を検出する変化検出手段と、前記判定レベル切替手段の判定レベルと平均温度検出手段の検出値とを比較しヒータへの通電の決定するとともに、変化検出手段の変化検出値が所定の変化を示さない時に通電手段の異常を検出する温度制御手段とを備えた構成としたものである。
【０００９】
平均温度検出手段の変化を検出することで、通電手段が通電状態か否かを検出することができるため、通電手段を通電状態にしたにも関わらず非通電状態であるときに、片側の通電手段の故障と判定することができ、通電を停止させることで、使用者に不快感を与えることを防ぐことができる。
【００１０】
【発明の実施の形態】
請求項１に記載の発明は、面状採暖具本体に配設された複数のヒータと、前記複数のヒータの平均温度を検出する平均温度検出手段と、前記複数のヒータへ通電を行う通電手段と、前記複数のヒータのうち、幾つのヒータを通電状態にするかにより判定レベルを切り替える判定レベル切替手段と、前記平均温度検出手段の検出値の変化を検出する変化検出手段と、前記判定レベル切替手段の判定レベルと平均温度検出手段の検出値とを比較しヒータへの通電を決定するとともに、変化検出手段の変化検出値が所定の変化を示さない時に通電手段の異常を検出する温度制御手段とを備えた構成とすることにより、平均温度検出手段の変化を検出することで、通電手段が通電状態か否かを検出することができるため、通電手段を通電状態にしたにも関わらず実際には非通電状態であるときは、温度変化が所定の変化を示さないので、片側の通電手段の故障と判定することができ、通電を停止させるあるいは異常であることを表示することで、使用者に不快感を与えることを防ぐことができる。
【００１１】
請求項２に記載の発明は、特に、請求項１に記載の変化検出手段を、複数のヒータの一つを通電状態にしたときの平均温度検出手段の検出値の変化を検出するようにしたことにより、通電を始めるタイミングで、片側の通電手段の故障を検出することができ、早い段階で通電を停止させ、使用者に不快感を与えることを防ぐことができる。
【００１２】
請求項３に記載の発明は、特に、請求項１に記載の変化検出手段を、複数のヒータの通電状態の後において、一つのヒータを非通電状態にしたときの平均温度検出手段の検出値の変化を検出するようにしたことにより、ヒータの温度が上昇した状態、すなわち平均温度検出手段の検出値がより変化の大きい領域で検出することができるため、より高い精度で片側の通電手段の故障を検知することができる。
【００１３】
請求項４に記載の発明は、変化検出手段を、複数のヒータが非通電状態のときの平均温度検出手段の検出値と、複数のヒータの通電状態の後に一つのヒータのみを非通電状態にしたときの平均温度検出手段の検出値との差を検出することにより、検出値を所定の絶対値で判定するのではなく、検出値の差で判定するため、回路的なばらつきの影響を受けず、より確実に片側の通電手段の故障を検知することができる。
【００１４】
請求項５に記載の発明は、通電状態が切り替わってからの時間を計時する通電時間計時手段を有し、通電時間計時手段の計時時間が所定時間経過後に平均温度検出手段の検出値の変化を検出することにより、平均温度検出手段の検出値が安定したタイミングで検出することができ、より確実に片側の通電手段の故障を検知することができる。
【００１５】
請求項６に記載の発明は、変化検出手段を、平均温度検出手段の検出値と判定レベルとの比較により各ヒーターへの通電手段の状態を切り替える際に、前記通電手段の切り替える順番を順次切り替えて平均温度検出手段の検出値の変化を検出するようにしたので、それぞれのヒータに生じる温度差を抑制することができる。
【００１６】
【実施例】
以下、本発明の実施例について、図面を参照しながら説明する。
【００１７】
（実施例１）
図１は、本発明の第１の実施例における面状採暖具のブロック図である。図１に示すように、面状採暖具本体（図示せず）に半面ずつ配設されたヒータＡ１と温度検知線Ａ２、及びヒータＢ３と温度検知線Ｂ４は、それぞれ温度によりインピーダンスが変化する感温材Ａ５及び感温材Ｂ６をはさんで構成された感温ヒータ線Ａ７及び感温ヒータ線Ｂ８と、ヒータＡ１の温度とヒータＢ３の温度との平均温度を検出する一つの平均温度検出手段９と、ヒータＡ１とヒータＢ３それぞれに通電を行うためのリレーからなる通電手段Ａ１０及び通電手段Ｂ１１と、全面通電と半面通電とで温度制御を行う判定レベルを切り替える判定レベル切替手段１３と、平均温度検出手段９の検出値の変化を検出する変化検出手段１４と、判定レベル検出手段１３によって切り替わった判定レベルと平均温度検出手段９の検出値と変化検出手段１４の検出値により各ヒータへの通電を制御する温度制御手段１２とからなる。
【００１８】
以上のように構成された面状採暖具について、以下その動作、作用を説明する。
【００１９】
図２は、両方の通電手段（通電手段Ａ１０及び通電手段Ｂ１１）が非通電状態から片側の通電手段のみを通電状態にしたときの、平均温度検出手段９の検出値の変化を表した図である。ここで、図２（ａ）のように、通電状態にした側の通電手段（例えば通電手段Ａ１０）が正常であれば、平均温度検出手段９の検出値はヒータ温度に応じて変化する。一方、通電手段Ａ１０が故障していた場合は、両方の通電手段が非通電状態ということになるので、前述の通り、図２（ｂ）のように、平均温度検出手段９の検出値は変化しない。
【００２０】
本実施例では、片側の通電手段のみを通電状態にしたときの平均温度検出手段９の検出値の変化が、図２（ａ）または図２（ｂ）のどちらの状態であるかを変化検出手段１４において検出することで、通電手段が正常であるか、異常（故障）であるかを判定し、異常（故障）であれば通電を停止させる。
【００２１】
以上のように、全面通電時に一旦片側の通電手段のみを通電状態にしたときの、平均温度検出手段９の検出値の変化を変化検出手段１４において検出することで、通電状態にした側の通電手段Ａ１０が故障しているか否かを検出することができ、使用者に不快感を与える前に通電を停止させることができる。
【００２２】
また、通電を開始するタイミングで故障検知できることから、早い段階で故障検知を行うことができる。
【００２３】
なお、本実施例では通電手段Ａ１０が故障した場合について記載したが、通電手段Ｂ１１が故障した場合でも、同様に検出が可能である。
【００２４】
（実施例２）
本発明の第２の実施例について図面を用いて説明する。
【００２５】
図３は、両方の通電手段が通電状態のときに、片側の通電手段のみ非通電状態にしたときの、平均温度検出手段９の検出値の変化を表した図である。ここで、図３（ａ）のように、両方の通電手段が正常なときの平均温度検出手段９の検出値は、全面通電から半面通電に切り替わることになるので、半面通電時の検出値が検出されることになる。一方、図３（ｂ）のように、非通電状態にした側と反対側の通電手段が故障して通電状態にならない場合には、両方の通電手段が非通電状態となることから、前述のように、平均温度検出手段９の検出値は両方の通電手段が非通電状態、すなわち検出値Ｖ０で一定となる。このことから、両方の通電手段が正常なときと、片側の通電手段が故障しているときとで、平均温度検出手段９の検出値の変化に差が発生することになる。この平均温度検出手段９の検出値の変化を変化検出手段１４において検出することで、片側の通電手段が故障しているか否かを検出することができる。
【００２６】
以上のように、全面通電時に一旦片側の通電手段のみを非通電状態にしたときの、平均温度検出手段９の検出値の変化を変化検出手段１４において検出することで、非通電状態にした側と反対側の通電手段が故障しているか否かを検出することができ、使用者に不快感を与える前に通電を停止させることができる。
【００２７】
また、通電状態から非通電状態への切替時に検出することから、検出温度の高い領域、すなわち平均温度検出手段９の検出値の変化の大きい領域で検出することができ、より精度の高い検出が可能となる。
【００２８】
（実施例３）
本発明の第３の実施例について図面を用いて説明する。
【００２９】
平均温度検出手段９の検出値は、回路ばらつき等によって絶対値に個体差が発生してしまう。このため、例えば平均温度検出手段９の検出値が変化したか否かを判定するのに、平均温度検出手段９の検出値の変化が、ある所定の絶対値以上ならば正常、ある所定の絶対値未満ならば異常というように判定すると、回路ばらつき等によって、正常状態を異常状態、もしくは異常状態を正常状態と誤判定してしまうおそれがある。
【００３０】
ここで、図４のように、両方の通電手段が非通電状態のときの平均温度検出手段９の検出値（Ｖ３）と、両方の通電手段が通電している状態から片側の通電手段のみを非通電状態にしたときの平均温度検出手段９の検出値（Ｖ４）との差について考えると、両方の通電手段が正常なときには、図４（ａ）のように、ヒータ温度に応じて検出値が変化しているので、Ｖ３≧Ｖ４となり、非通電状態にした通電手段の反対側の通電手段が故障しているときには、図４（ｂ）のように、両方の通電手段が非通電状態となることから、Ｖ３＝Ｖ４となる。このことから、Ｖ３≠Ｖ４であれば通電手段は正常、Ｖ３＝Ｖ４であれば通電手段が故障と判定することができる。
【００３１】
以上のように、両方の通電手段が非通電状態のときの平均温度検出手段９の検出値と、両方の通電手段が通電している状態から片側の通電手段のみを非通電状態にしたときの平均温度検出手段９の検出値との差を検出することで、回路的なばらつきの影響を受けず確実に、片側の通電手段の故障の有無を検出することができる。
【００３２】
（実施例４）
図５は、本発明の第４の実施例における面状採暖具のブロック図である。図５に示すように、通電手段Ａ１０もしくは通電手段Ｂ１１の状態が切り替わってからの時間を計時する通電時間計時手段１５を有し、通電時間計時手段１５の計時時間が所定時間経過後に平均温度検出手段９の検出値の変化を検出するものである。
【００３３】
通電手段の状態が切り替わったときには、回路的なばらつきや時定数によって、平均温度検出手段９の検出値が安定するまでに時間を要する。そのため、通電手段の状態が切り替わってからの通電時間を計時し、所定時間後から検出を始めることで、平均温度検出温度９の検出値が十分安定した状態で検出することができる。
【００３４】
以上のように、通電手段の状態が切り替わってからの通電時間を計時し、所定時間後から平均温度検出手段９の検出値の変化を検出し始めることで、より確実に片側の通電手段の故障を検出することができる。
【００３５】
また、通電手段Ａ１０及び通電手段Ｂ１１の状態の切替をランダムに行ってしまうと、一方のヒータの温度が上がったり下がったりするおそれがあることから、それぞれのヒータに温度差が生じ、使用者に不快感を与えてしまう。
【００３６】
そこで、設定温度に到達したことによる通常の温度制御によって、通電手段の状態が切り替わるタイミングで、前述のように、片側の通電手段のみを通電状態あるいは非通電状態にすることで、通常の温度制御への影響を極力減少させ、快適な暖感覚が提供できる。
【００３７】
また、例えば今回通電手段Ａ１０を非通電状態にすると、次のタイミングでは通電手段Ｂ１１を非通電状態にするというように、通電手段の切替を交互に行うことで、それぞれのヒータに発生する温度差を緩和し、使用者に不快感を与えないようにすることができる。
【００３８】
【発明の効果】
以上のように、本発明によれば、全面通電時に片側の通電手段の故障を検知することができ、使用者に不快感を与える前に通電を停止させることができる。
【図面の簡単な説明】
【図１】本発明の実施例１における面状採暖具のブロック図
【図２】（ａ）本発明の実施例１において、通電手段が正常な時の平均温度検出手段の検出値のグラフ
（ｂ）本発明の実施例１において、通電手段が故障の時の平均温度検出手段の検出値のグラフ
【図３】（ａ）本発明の実施例２において、通電手段が正常な時の平均温度検出手段の検出値のグラフ
（ｂ）本発明の実施例２において、通電手段が故障の時の平均温度検出手段の検出値のグラフ
【図４】（ａ）本発明の実施例３において、通電手段が正常な時の平均温度検出手段の検出値のグラフ
（ｂ）本発明の実施例３において、通電手段が故障の時の平均温度検出手段の検出値のグラフ
【図５】本発明の実施例５における面状採暖具のブロック図
【図６】従来の面状採暖具のブロック図
【図７】平均温度検出手段の検出値とヒータ温度との関係を表した図
【図８】片側の通電手段が故障したときの平均温度検出手段の検出値を示した図
【符号の説明】
１ヒータＡ（ヒータ）
３ヒータＢ（ヒータ）
９平均温度検出手段
１０通電手段Ａ（通電手段）
１１通電手段Ｂ（通電手段）
１２温度制御手段
１３判定レベル切替手段
１４変化検出手段
１５通電時間計時手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet heating device such as an electric carpet, an electric blanket, and floor heating.
[0002]
[Prior art]
Conventionally, as shown in FIG. 6, for example, this type of planar warming tool includes a heater A1 and a temperature detection line A2, and a heater B3 and a temperature detection that are arranged on each half surface of the planar warming tool body (not shown). The line B4 constitutes a temperature-sensitive heater line A7 and a temperature-sensitive heater line B8 with the temperature-sensitive material A5 and the temperature-sensitive material B6 whose impedances change depending on the temperature, respectively. Hereinafter, the warming tool is divided into two, and one is referred to as A-side and the other as B-side.
[0003]
When the temperature of the planar warming tool changes due to the heat generated by the heater A1, the impedance of the temperature sensitive material A5 changes, and the current flowing from the temperature detection line A2 to the heater A1 changes. Further, the current flowing from the temperature detection line B4 to the heater B3 also changes on the B side as in the A side.
[0004]
This current change is taken out as a voltage signal and temperature detection is performed. However, if temperature detection is performed independently, the number of parts of the temperature detection circuit increases and the cost increases, so the current flowing through each temperature detection line is synthesized. The average temperature is detected by one average temperature detecting means 9 by taking out the voltage signal. Here, the relationship between the detected value of the average temperature detecting means 9 and the heater temperature is shown in FIG. When the energizing means A10 for energizing the heater A1 or the energizing means B11 for energizing the heater B3 is in the energized state, the impedance of the temperature sensitive material A5 or the temperature sensitive material B6 decreases as the heater temperature rises. Become. On the other hand, the detected value (voltage) of the average temperature detecting means 9 is reduced as the temperature increases as shown in the figure, and the circuit configuration is such that the maximum value (V0) is obtained when the heater is not energized. . When the detected value has decreased to a signal level corresponding to the temperature set by the user, the temperature control means 12 performs temperature control so that the energization means is in a non-energized state.
[0005]
Here, since current does not flow when the energizing means is in the non-energized state, both the energizing means on both the A and B sides are energized (full energization), and when the energizing means on only one side is energized (half surface) In the case of energization, the current flowing through the heater is different even at the same temperature. From this, the relationship of the detected value of the average temperature detection means 9 with respect to the heater temperature differs between full-surface energization and half-surface energization. Accordingly, the determination level for determining whether the heater is turned on or off is compared with the detected value by the determination level switching means 13 when the entire surface is energized. When the entire surface is energized, the determination level for the entire surface (V1). Is switched to the half-side determination level (V2), and the temperature control means 12 performs temperature control based on the determination level.
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, when a failure occurs such that the energization means on one side, for example, the energization means A10, cannot be energized even though the energization is performed on the entire surface, as shown in FIG. Since the temperature control is performed at the determination level (V1) for the entire surface instead of (V2), the energization is continued even if the detection value of the average temperature detecting means 9 is lower than the determination level (V2) for the half surface, and there is a failure. The energizing time T1 of the non-energizing means B11 is longer than the energizing time T2 when the energizing means is normal, and the temperature of the heater B3 is controlled at a much higher temperature than the original set temperature. Therefore, the configuration is such that the user is uncomfortable that the non-failed side is too hot and the failed side is too slim.
[0007]
An object of the present invention is to solve the above-described conventional problems, and to detect a failure of the energizing means on one side so as not to give the user a discomfort.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned conventional problems, heaters arranged on each surface of the sheet heating tool main body, average temperature detecting means for detecting the average temperature of each heater temperature, energizing means for energizing each heater, Among the plurality of heaters, a determination level switching unit that switches a determination level depending on how many heaters are energized, a change detection unit that detects a change in a detection value of an average temperature detection unit, and a determination level switching unit A temperature control unit that compares the determination level with the detection value of the average temperature detection unit to determine energization of the heater and detects an abnormality of the energization unit when the change detection value of the change detection unit does not show a predetermined change ; It is set as the structure provided with.
[0009]
By detecting the change in the average temperature detecting means, it is possible to detect whether or not the energizing means is energized. Therefore, when the energizing means is in the energized state, it is energized on one side. It can be determined that the device has failed, and disabling energization can prevent the user from feeling uncomfortable.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 is a plurality of heaters arranged in the surface warmer main body, an average temperature detecting means for detecting an average temperature of the plurality of heaters, and an energizing means for energizing the plurality of heaters. When, among the plurality of heaters, and determining the level switching means for switching the decision level depending on whether the number of heaters energized, and the change detecting means for detecting a change in the detection value of the average temperature detecting means, the determination level Temperature control that compares the determination level of the switching means with the detection value of the average temperature detection means to determine energization to the heater and detects an abnormality of the energization means when the change detection value of the change detection means does not show a predetermined change By detecting the change in the average temperature detecting means, it is possible to detect whether the energizing means is in the energized state, so that the energizing means is in the energized state. Regardless of whether the current is actually not energized, the temperature change does not show a predetermined change, so it can be determined that the energization means on one side has failed, and the energization is stopped or an indication of an abnormality is displayed. Therefore, it is possible to prevent the user from feeling uncomfortable.
[0011]
In the invention described in claim 2, in particular, the change detecting means described in claim 1 is adapted to detect a change in the detected value of the average temperature detecting means when one of the plurality of heaters is energized. Thus, it is possible to detect a failure of the energization means on one side at the timing of starting energization, and to stop energization at an early stage and prevent the user from feeling uncomfortable.
[0012]
The invention according to claim 3 is the detection value of the average temperature detecting means when the change detecting means according to claim 1 is in a state where one heater is not energized after the energized state of the plurality of heaters. As a result of detecting the change of the heater, the temperature of the heater has risen, that is, the detection value of the average temperature detection means can be detected in a region where the change is larger, so that the power supply means on one side can be detected with higher accuracy. A failure can be detected.
[0013]
In the invention according to claim 4, the change detection means is configured such that only one heater is de-energized after the detected value of the average temperature detection means when the plurality of heaters are in the non-energized state and the energized state of the plurality of heaters. By detecting the difference from the detected value of the average temperature detecting means at this time, the detected value is determined not by a predetermined absolute value but by the detected value difference. Therefore, it is possible to detect a failure of the energizing means on one side more reliably.
[0014]
The invention according to claim 5 has energization time counting means for measuring the time after the energization state is switched, and the change in the detected value of the average temperature detection means after the predetermined time has elapsed. By detecting, the detection value of the average temperature detection means can be detected at a stable timing, and the failure of the energization means on one side can be detected more reliably.
[0015]
According to the sixth aspect of the present invention, when the change detecting means switches the state of the energizing means to each heater by comparing the detection value of the average temperature detecting means with the determination level, the switching order of the energizing means is sequentially switched. Since the change in the detected value of the average temperature detecting means is detected, the temperature difference generated in each heater can be suppressed.
[0016]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0017]
Example 1
FIG. 1 is a block diagram of a planar warmer in the first embodiment of the present invention. As shown in FIG. 1, the heater A1 and the temperature detection line A2, and the heater B3 and the temperature detection line B4, which are arranged on the half surface of the surface warming tool main body (not shown), each have a sense that the impedance changes depending on the temperature. A temperature-sensitive heater wire A7 and a temperature-sensitive heater wire B8 that are sandwiched between the temperature material A5 and the temperature-sensitive material B6, and one average temperature detection means for detecting the average temperature of the temperature of the heater A1 and the temperature of the heater B3. 9, energizing means A10 and energizing means B11 composed of relays for energizing each of the heaters A1 and B3, a judgment level switching means 13 for switching judgment levels for performing temperature control between full energization and half energization, and average Change detection means 14 for detecting a change in the detection value of the temperature detection means 9, the determination level switched by the determination level detection means 13, the detection value of the average temperature detection means 9 and the change The detection value of the detecting means 14 consisting of the temperature control means 12 for controlling the energization to the heaters.
[0018]
About the planar warming tool comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.
[0019]
FIG. 2 is a diagram showing a change in the detected value of the average temperature detecting means 9 when both the energizing means (the energizing means A10 and the energizing means B11) are switched from the non-energized state to the energized state only on one side. is there. Here, as shown in FIG. 2A, if the energizing means (for example, energizing means A10) on the energized side is normal, the detected value of the average temperature detecting means 9 changes according to the heater temperature. On the other hand, when the energizing means A10 is out of order, both energizing means are in a non-energized state, and as described above, the detected value of the average temperature detecting means 9 changes as shown in FIG. do not do.
[0020]
In the present embodiment, it is detected whether the change in the detected value of the average temperature detecting means 9 when only one of the energizing means is energized is in the state of FIG. 2 (a) or FIG. 2 (b). By detecting in the means 14, it is determined whether the energizing means is normal or abnormal (failure). If abnormal (failure), the energization is stopped.
[0021]
As described above, the change detection means 14 detects the change in the detected value of the average temperature detection means 9 when only one of the energization means is once energized during full energization, thereby energizing the energized side. It can be detected whether or not the means A10 is out of order, and the energization can be stopped before the user feels uncomfortable.
[0022]
Moreover, since failure detection can be performed at the timing of starting energization, failure detection can be performed at an early stage.
[0023]
In the present embodiment, the case where the energizing unit A10 fails is described. However, even when the energizing unit B11 fails, the same detection is possible.
[0024]
(Example 2)
A second embodiment of the present invention will be described with reference to the drawings.
[0025]
FIG. 3 is a diagram showing a change in the detected value of the average temperature detecting means 9 when both energizing means are energized and only the energizing means on one side is de-energized. Here, as shown in FIG. 3A, the detected value of the average temperature detecting means 9 when both the energizing means are normal switches from full energization to half energization. Will be detected. On the other hand, as shown in FIG. 3B, when the energizing means on the side opposite to the non-energized state fails and does not enter the energized state, both energizing means become non-energized. Thus, the detected value of the average temperature detecting means 9 becomes constant when both energizing means are in the non-energized state, that is, the detected value V0. Therefore, a difference occurs in the change in the detected value of the average temperature detecting means 9 between when both the energizing means are normal and when one of the energizing means is out of order. By detecting the change in the detected value of the average temperature detecting means 9 in the change detecting means 14, it is possible to detect whether or not the energizing means on one side is out of order.
[0026]
As described above, the change detection means 14 detects a change in the detected value of the average temperature detection means 9 when only one of the energization means is once de-energized during full energization. It is possible to detect whether or not the energizing means on the opposite side is out of order, and the energization can be stopped before the user feels uncomfortable.
[0027]
Further, since detection is performed when switching from the energized state to the non-energized state, detection can be performed in a region where the detected temperature is high, that is, a region where the change in the detected value of the average temperature detecting means 9 is large. It becomes possible.
[0028]
(Example 3)
A third embodiment of the present invention will be described with reference to the drawings.
[0029]
The detected value of the average temperature detecting means 9 causes individual differences in absolute values due to circuit variations and the like. For this reason, for example, to determine whether or not the detection value of the average temperature detection means 9 has changed, if the change in the detection value of the average temperature detection means 9 is greater than or equal to a certain predetermined absolute value, it is normal. If it is determined to be abnormal if it is less than the value, there is a risk that the normal state will be erroneously determined as an abnormal state or the abnormal state as a normal state due to circuit variations or the like.
[0030]
Here, as shown in FIG. 4, the detected value (V3) of the average temperature detecting means 9 when both energizing means are in the non-energized state, and only one energizing means from the state where both energizing means are energized. Considering the difference from the detected value (V4) of the average temperature detecting means 9 when the energized state is established, when both energizing means are normal, the detected value according to the heater temperature as shown in FIG. Therefore, when V3 ≧ V4 and the energization means on the opposite side of the energization means in the non-energized state is out of order, both energization means are in the non-energized state as shown in FIG. Therefore, V3 = V4. From this, it can be determined that the energization means is normal if V3 ≠ V4, and the energization means is faulty if V3 = V4.
[0031]
As described above, the detected value of the average temperature detecting means 9 when both energizing means are in the non-energized state and when only one energizing means is de-energized from the state where both energizing means are energized. By detecting the difference from the detection value of the average temperature detecting means 9, it is possible to reliably detect the presence or absence of a failure of the energizing means on one side without being affected by circuit variations.
[0032]
Example 4
FIG. 5 is a block diagram of a planar warming tool in the fourth embodiment of the present invention. As shown in FIG. 5, it has energization time timing means 15 for measuring the time after the state of energization means A10 or energization means B11 is switched, and the average temperature is detected after a predetermined time has elapsed. A change in the detection value of the means 9 is detected.
[0033]
When the state of the energizing means is switched, it takes time until the detected value of the average temperature detecting means 9 is stabilized due to circuit variations and time constants. Therefore, by measuring the energization time after the state of the energization means is switched and starting detection after a predetermined time, the detection value of the average temperature detection temperature 9 can be detected in a sufficiently stable state.
[0034]
As described above, by measuring the energization time after the state of the energization means is switched and starting to detect a change in the detected value of the average temperature detection means 9 after a predetermined time, the failure of the energization means on one side is more reliably performed. Can be detected.
[0035]
In addition, if the state of the energizing unit A10 and the energizing unit B11 is switched randomly, the temperature of one heater may rise or fall, resulting in a temperature difference between the heaters, which is inconvenient for the user. Gives pleasure.
[0036]
Therefore, normal temperature control is performed by switching only one of the energizing means to the energized state or the non-energized state as described above at the timing when the state of the energizing means is switched by the normal temperature control when the set temperature is reached. Can reduce the influence on the body as much as possible and provide a comfortable warm feeling.
[0037]
Further, for example, when the energization unit A10 is deenergized this time, the energization unit B11 is de-energized at the next timing, so that the energization unit is switched alternately so that the temperature difference generated in each heater is changed. Can be alleviated so as not to cause discomfort to the user.
[0038]
【The invention's effect】
As described above, according to the present invention, it is possible to detect a failure of the energizing means on one side during energization of the entire surface, and it is possible to stop energization before giving the user unpleasant feeling.
[Brief description of the drawings]
FIG. 1 is a block diagram of a planar warming tool in Embodiment 1 of the present invention. FIG. 2 is a graph of detected values of an average temperature detecting means when the energizing means is normal in Embodiment 1 of the present invention. b) Graph of the detected value of the average temperature detecting means when the energizing means fails in Example 1 of the present invention. FIG. 3 (a) Average temperature when the energizing means is normal in Example 2 of the present invention. Graph of detection value of detection means (b) Graph of detection value of average temperature detection means when the energization means failed in Example 2 of the present invention. FIG. 4 (a) Energization in Example 3 of the present invention. (B) Graph of the detected value of the average temperature detecting means when the energizing means fails in the third embodiment of the present invention FIG. 5 is a graph of the detected value of the average temperature detecting means when the means is normal. Block diagram of a planar warmer in Example 5 [Fig. 6] Conventional planar warmer Block diagram [Fig. 7] A diagram showing the relationship between the detected value of the average temperature detecting means and the heater temperature. [Fig. 8] A diagram showing the detected value of the average temperature detecting means when the energizing means on one side fails. Explanation】
1 Heater A (Heater)
3 Heater B (Heater)
9 Mean temperature detection means 10 Energization means A (energization means)
11 Energizing means B (energizing means)
12 Temperature control means 13 Judgment level switching means 14 Change detection means 15 Energization time counting means

Claims

Among the plurality of heaters, a plurality of heaters disposed in the surface warming tool main body, an average temperature detecting means for detecting an average temperature of the plurality of heaters, an energizing means for energizing the plurality of heaters, and the plurality of heaters , and determining the level switching means for switching the decision level depending on whether the number of heaters energized, and the change detecting means for detecting a change in the detection value of the average temperature detecting means, average temperature detection and determination level of the determination level switching means and determines the energization of the comparison the heater and detecting value of the unit, the surface shape and a temperature control means for detecting an abnormality of the current supply means when the change detection value of the change detection means does not indicate a predetermined change Heating tool.

The planar warmer according to claim 1, wherein the change detecting means detects a change in a detected value of the average temperature detecting means when one of the plurality of heaters is energized.

2. The planar shape according to claim 1, wherein the change detecting means detects a change in a detected value of the average temperature detecting means when one heater is in a non-energized state after a plurality of heaters are energized. Heating tool.

The change detection means is a detection value of the average temperature detection means when a plurality of heaters are in a non-energized state, and a detection value of the average temperature detection means when only one heater is in a non-energized state after the plurality of heaters are energized. The surface warmer according to claim 1, wherein a difference from the value is detected.

An energization time measuring means for measuring the time from when the energized state is switched, and the change detecting means detects a change in the detected value of the average temperature detecting means after a predetermined time has elapsed from the energized time measuring means; The planar warming tool according to any one of claims 1 to 4, wherein:

When the change detection means switches the state of the energization means to each heater by comparing the detection value of the average temperature detection means and the determination level, the change detection means sequentially switches the switching order of the energization means, and the detection value of the average temperature detection means The planar warming tool according to any one of claims 2 to 5, wherein a change in temperature is detected.