JPH0318203B2 - - Google Patents
Info
- Publication number
- JPH0318203B2 JPH0318203B2 JP58179405A JP17940583A JPH0318203B2 JP H0318203 B2 JPH0318203 B2 JP H0318203B2 JP 58179405 A JP58179405 A JP 58179405A JP 17940583 A JP17940583 A JP 17940583A JP H0318203 B2 JPH0318203 B2 JP H0318203B2
- Authority
- JP
- Japan
- Prior art keywords
- electrode
- temperature
- circuit
- heating element
- sensor electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 claims description 26
- 239000000463 material Substances 0.000 claims description 13
- 230000005611 electricity Effects 0.000 claims description 3
- 238000001514 detection method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 6
- 238000009499 grossing Methods 0.000 description 6
- 238000009413 insulation Methods 0.000 description 3
- 230000002265 prevention Effects 0.000 description 3
- 239000003990 capacitor Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 238000013021 overheating Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
- G05D23/24—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature the sensing element having a resistance varying with temperature, e.g. a thermistor
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Control Of Resistance Heating (AREA)
- Control Of Temperature (AREA)
Description
【発明の詳細な説明】
（技術分野）
本発明はホツトカーペツト等に用いられる温度
制御回路に関する。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a temperature control circuit used for hot carpets and the like.
（背景技術）
ホツトカーペツト等の床暖房器具にあつてはフ
イルム状の発熱体（面状発熱体）が用いられ、面
積的にも広いため各部の温度を平均的に検出する
ために種々の方式が提案されている。(Background technology) In floor heating equipment such as hot carpets, a film-shaped heating element (planar heating element) is used, and since the area is large, various methods are used to average the temperature of each part. Proposed.
第１図は従来の温度制御回路における温度検出
のための構成を示したものであり、発振器１３で
ヒータ電極１２ａに接続される商用電源１１の周
波数（商用周波）とは異なる周波数の信号を発生
し、ハイパスフイルタ１４、コンデンサCSを介し
て、感熱材１２ｃを挟んでヒータ電極１２ａと対
向するセンサ電極１２ｂに発振信号を印加し、こ
のセンサ電極１２ｂに生じる分担電圧をハイパス
フイルタ１５を介した後に同期検波回路１６によ
り直流的な温度検出信号VOUTを取り出すように
している。 Figure 1 shows the configuration for temperature detection in a conventional temperature control circuit, in which an oscillator 13 generates a signal with a frequency different from the frequency (commercial frequency) of the commercial power supply 11 connected to the heater electrode 12a. Then, an oscillation signal is applied via the high-pass filter 14 and the capacitor C S to the sensor electrode 12b facing the heater electrode 12a with the heat-sensitive material 12c in between, and the shared voltage generated at the sensor electrode 12b is applied via the high-pass filter 15. Later, a synchronous detection circuit 16 extracts a direct current temperature detection signal V OUT .
すなわち、面状発熱体１２のヒータ電極１２ａ
とセンサ電極１２ｂとの間に配設されたフイルム
状の感熱材１２ｃは負特性サーミスタとして動作
するものであり、等価回路で示せば第２図のよう
にヒータ電極１２ａがアース電極となつて発振器
１３に対してコンデンサCSと感熱材１２ｃの等価
キヤパシタンスCTが直列接続されたものとなる。
しかして、面状発熱体１２の温度変化と共に感熱
材１２ｃのインピーダンスが変化し、端子Ａに生
じる発振信号の振幅が変化することになり、この
信号振幅を同期検波回路１６で取り出すことによ
り温度変化に追随した信号を得ることができる。 That is, the heater electrode 12a of the planar heating element 12
The film-shaped heat-sensitive material 12c disposed between the sensor electrode 12b and the sensor electrode 12b operates as a negative characteristic thermistor, and as shown in FIG. 13, the capacitor C S and the equivalent capacitance C T of the heat-sensitive material 12c are connected in series.
As a result, the impedance of the heat-sensitive material 12c changes with the temperature change of the planar heating element 12, and the amplitude of the oscillation signal generated at the terminal A changes. It is possible to obtain a signal that follows the
ところで、センサ電極１２ｂには感熱材１２ｃ
を介してヒータ電極１２ａから商用周波の信号も
誘起し、この電圧も面状発熱体１２の温度に応じ
て変化することから、商用周波信号を用いて温度
検出することも考えられるが、ヒータ電極１２ａ
から伝わる電圧はその点の電圧に比例したものと
なるため、面状発熱体１２の位置によつて信号電
圧が異なり、よつて部分断熱等により面状発熱体
１２の温度が均一でなくなると出力信号は平均温
度を示さなくなるためこの方法を用いることはで
きない。そのため、第１図の如く商用周波とは異
なる周波数の発振器１３を必要とし、更にセンサ
電極１２ｂに混入する商用周波信号を除去するた
めにハイパスフイルタ１４，１５および同期検波
回路１６といつた回路を必要とすることとなり、
構成が複雑になると共にコストダウンを図れない
という欠点があつた。 By the way, the sensor electrode 12b is provided with a heat-sensitive material 12c.
Since a commercial frequency signal is also induced from the heater electrode 12a via the heater electrode 12a, and this voltage also changes depending on the temperature of the sheet heating element 12, it is conceivable to detect the temperature using the commercial frequency signal. 12a
Since the voltage transmitted from the is proportional to the voltage at that point, the signal voltage varies depending on the position of the sheet heating element 12, and therefore, if the temperature of the sheet heating element 12 becomes uneven due to partial insulation etc., the output will change. This method cannot be used because the signal will no longer represent the average temperature. Therefore, an oscillator 13 with a frequency different from the commercial frequency is required as shown in FIG. It becomes necessary,
This has the disadvantage that the configuration becomes complicated and costs cannot be reduced.
（発明の目的）
本発明は上記の点に鑑み提案されたものであ
り、温度検出を商用周波で行うことにより構成の
簡略化およびコストダウンを図つた温度制御回路
を提供することを目的とする。(Objective of the Invention) The present invention has been proposed in view of the above points, and an object of the present invention is to provide a temperature control circuit that simplifies the configuration and reduces costs by performing temperature detection at a commercial frequency. .
（発明の開示）
第３図イは本発明の温度制御回路に用いられる
面状発熱体の構成を示したもので、ヒータ電極２
ａは往路と復路が近接して配置される100V−0V
混合構成となつており、面状発熱体２の各部での
平均電圧が50Vとなるように構成されている。ま
た、センサ電極２ｂはヒータ電極２ａと同一平面
内に平行して設けられ、ヒータ電極２ａとセンサ
電極２ｂは感熱材２ｂを介して対向する反射電極
２ｃにより電気的に結合されている。第３図ロは
面状発熱体２の一部を断面図で示したものであ
り、負特性サーミスタとして動作するフイルム状
の感熱材２ｄの一面にヒータ電極２ａ、センサ電
極２ｂが、他面に反射電極２ｃがエツチング処理
等によつて形成されている。(Disclosure of the Invention) Figure 3A shows the configuration of a planar heating element used in the temperature control circuit of the present invention.
a is 100V-0V where the outbound and return routes are placed close to each other
It has a mixed configuration, and is configured so that the average voltage at each part of the sheet heating element 2 is 50V. Further, the sensor electrode 2b is provided in parallel with the heater electrode 2a on the same plane, and the heater electrode 2a and the sensor electrode 2b are electrically coupled by a reflective electrode 2c facing each other via a heat-sensitive material 2b. FIG. 3B is a cross-sectional view of a part of the planar heating element 2, in which a heater electrode 2a and a sensor electrode 2b are arranged on one side of a film-shaped heat-sensitive material 2d that operates as a negative characteristic thermistor, and on the other side. A reflective electrode 2c is formed by etching or the like.
第４図は本発明の温度制御回路の一実施例を示
すブロツク構成図であり、２は第３図で示した面
状発熱体である。第４図において面状発熱体２の
ヒータ電極２ａの両端にはリレー接点S1，S2を介
して商用電源１が接続されており、センサ電極２
ｂの両端は互いに接続され、抵抗Ｒを介してアー
スラインに接続されると共に平滑回路３に接続さ
れている。ここで、平滑回路３は入力された商用
周波信号を整流・平滑して直流化を行うもので、
その出力端子はスイツチング回路４および過昇防
止回路５に共に接続され、スイツチング回路４の
出力によりリレー駆動回路８が動作するようにな
つている。なお、スイツチング回路４は温度調整
器（図示せず）により設定温度に対応した信号が
与えられるものであり、平滑回路３から与えられ
る信号と設定値とを比較してスイツチング動作を
行う。また、過昇防止回路５は平滑回路３から与
えられる信号が異常に上昇した際に温度ヒユーズ
（図示せず）等を即断し、ヒータ電極２ａへの通
電を停止するための安全装置である。 FIG. 4 is a block diagram showing an embodiment of the temperature control circuit of the present invention, and numeral 2 designates the planar heating element shown in FIG. In FIG. 4, the commercial power source 1 is connected to both ends of the heater electrode 2a of the sheet heating element 2 via relay contacts S 1 and S 2 , and the sensor electrode 2
Both ends of b are connected to each other, to an earth line via a resistor R, and to the smoothing circuit 3. Here, the smoothing circuit 3 rectifies and smoothes the input commercial frequency signal to convert it into DC.
Its output terminal is connected to both a switching circuit 4 and an overheating prevention circuit 5, so that a relay drive circuit 8 is operated by the output of the switching circuit 4. The switching circuit 4 is supplied with a signal corresponding to a set temperature by a temperature regulator (not shown), and performs a switching operation by comparing the signal supplied from the smoothing circuit 3 with the set value. Further, the overheat prevention circuit 5 is a safety device for immediately cutting off a temperature fuse (not shown), etc., and stopping energization to the heater electrode 2a when the signal given from the smoothing circuit 3 rises abnormally.
一方、スイツチング回路４の出力はオフ時間タ
イマ６にも与えられており、リレー駆動回路８の
復帰はオフ時間タイマ６によつて行われるように
なつている。すなわち、スイツチング回路４の動
作によりリレーが駆動されて接点S1，S2がオフに
なつている期間はセンサ電極２ｂに信号が生じな
くなつて温度検出は行われず、見かけ上、温度が
低下したようになるので、適当な時間のオフ時間
タイマ６で設定し、この間はスイツチング回路４
の動作にかかわらず接点S1，S2をオフに保つよう
にしている。また、電源回路９は各回路に電源を
供給するためのものであり、漏電検出回路７は零
相変流器（図示せず）等により漏電を検出して強
制的にリレーをオフせしめて感電事故を防止する
ためのものである。 On the other hand, the output of the switching circuit 4 is also given to an off-time timer 6, so that the relay drive circuit 8 is reset by the off-time timer 6. That is, during the period when the relay is driven by the operation of the switching circuit 4 and the contacts S 1 and S 2 are turned off, no signal is generated at the sensor electrode 2b and no temperature detection is performed, and the temperature appears to drop. Therefore, the off time timer 6 is set to an appropriate time, and the switching circuit 4 is turned off during this time.
Contacts S 1 and S 2 are kept off regardless of the operation. The power supply circuit 9 is for supplying power to each circuit, and the earth leakage detection circuit 7 detects earth leakage using a zero-phase current transformer (not shown), etc., and forcibly turns off the relay to prevent electric shock. This is to prevent accidents.
動作にあたつて、面状発熱体２の温度が低い場
合は感熱材２ｄのインピーダンスが高く、ヒータ
電極２ａから感熱材２ｄおよび反射電極２ｃを介
してセンサ電極２ｂに流れる電流は小さく、よつ
て抵抗Ｒの両端に生じる商用周波信号は小さな値
となる。したがつて、平滑回路３によつて直流化
された信号はスイツチング回路４の設定温度に対
応した比較レベルに達しないためリレー駆動回路
８はリレー接点S1，S2をオ状態に保ち、ヒータ電
極２ａに通電を続けて加熱を行なう。 During operation, when the temperature of the planar heating element 2 is low, the impedance of the heat-sensitive material 2d is high, and the current flowing from the heater electrode 2a to the sensor electrode 2b via the heat-sensitive material 2d and the reflective electrode 2c is small. The commercial frequency signal generated across the resistor R has a small value. Therefore, since the signal converted into DC by the smoothing circuit 3 does not reach the comparison level corresponding to the set temperature of the switching circuit 4, the relay drive circuit 8 keeps the relay contacts S 1 and S 2 in the OFF state and turns off the heater. Electricity is continued to be supplied to the electrode 2a to perform heating.
次に、面状発熱体２の温度が設定温度に達する
とスイツチング回路４が反転動作してリレー駆動
回路８に信号を送出し、リレー接点S1，S2をオン
せしめてヒータ電極２ａへの通電を停止する。し
かして、ヒータ電極２ａが商用電源１と切離され
ることによりセンサ電極２ｂに生じていた信号電
圧は消失してスイツチング回路４は再び反転動作
を行うが、直前のオフ動作時にオフ時間タイマ６
が動作を開始して一定時間、リレー駆動回路８を
保持しているので接点S1，S2は即座にオンとはな
らず、オフ時間タイマ６で設定される一定の冷却
時間をおいて再びオンに復帰する。その後も上記
の動作を繰返し、よつて面状発熱体２は一定温度
に保たれることになる。 Next, when the temperature of the planar heating element 2 reaches the set temperature, the switching circuit 4 reverses its operation and sends a signal to the relay drive circuit 8, turning on the relay contacts S 1 and S 2 and turning on the heater electrode 2a. Stop energizing. As the heater electrode 2a is disconnected from the commercial power source 1, the signal voltage generated at the sensor electrode 2b disappears and the switching circuit 4 performs the inverting operation again.
Since the relay drive circuit 8 is held for a certain period of time after starting operation, the contacts S 1 and S 2 are not turned on immediately, but are turned on again after a certain cooling time set by the off time timer 6. Turn back on. Thereafter, the above operation is repeated, and thus the planar heating element 2 is kept at a constant temperature.
なお、面状発熱体２のヒータ電極２ａは100V
−0V混合構成になつているため感熱材２ｄを介
してセンサ電極２ｂに伝わる電圧は場所によらず
一定であり、温度のみに依存するため部分断熱等
によつて温度が均一でなくなつても平均温度を検
出して温度制御することができる。 In addition, the heater electrode 2a of the sheet heating element 2 has a voltage of 100V.
Since it has a -0V mixed configuration, the voltage transmitted to the sensor electrode 2b via the heat-sensitive material 2d is constant regardless of the location, and it depends only on the temperature, so even if the temperature is not uniform due to partial insulation etc. Temperature control can be performed by detecting the average temperature.
一方、上記の実施例で用いられる面状発熱体２
は第３図ロの如き断面構成になつているので、複
数のピン刺し等が起こると反射電極２ｃを介して
ヒータ電極２ａとセンサ電極２ｂが短絡される可
能性があるが、第４図中に示すように反射電極２
ｃのうち商用電源１の低圧側（アースライン側）
の部分２ｅを取り去り、ピン刺しが起きても低温
時に相当する低い検出電圧が印加されないように
することにより安全性を高めることができる。ま
た、センサ電極２ｂに断線が生じた際には温度検
出信号が消失して連続通電となる危険があるが、
第４図の如くセンサ電極２ｂの両端を接続してル
ープ構成としているため冗長性が高く、断線によ
る誤動作の発生を軽減することができる。 On the other hand, the planar heating element 2 used in the above embodiment
has a cross-sectional configuration as shown in FIG. 3B, so if multiple pin pricks occur, there is a possibility that the heater electrode 2a and sensor electrode 2b will be short-circuited via the reflective electrode 2c. Reflecting electrode 2 as shown in
Low voltage side of commercial power supply 1 (earth line side) of c
Safety can be improved by removing the portion 2e so that even if a pinprick occurs, a low detection voltage corresponding to a low temperature is not applied. Additionally, if a disconnection occurs in the sensor electrode 2b, there is a risk that the temperature detection signal will disappear and the current will continue to flow.
Since both ends of the sensor electrode 2b are connected to form a loop configuration as shown in FIG. 4, redundancy is high and malfunctions due to disconnection can be reduced.
（発明の効果）
叙上のように本発明によれば、温度制御回路に
おいて感熱材を介して、往路と復路とが近接して
配置されたヒータ電極とループ状に形成されたセ
ンサ電極とを有し、かつ前記ヒータ電極とセンサ
電極との間に複数の分割された反射電極を配設し
た面状発熱体を備え、前記センサ電極に生じる商
用周波電圧を整流・平滑し、所定値と比較してリ
レーを動作せしめ、このリレーにより前記ヒータ
電極への通電をオン・オフ制御することによつ
て、
(イ) 面状発熱体の部分断熱等により面状発熱体の
温度が均一でなくなつても、平均温度を検出し
て温度制御を行うことができる。(Effects of the Invention) As described above, according to the present invention, in a temperature control circuit, the heater electrode and the sensor electrode formed in a loop shape are connected to each other through a heat-sensitive material in the forward and return paths, which are arranged close to each other. and a planar heating element having a plurality of divided reflective electrodes arranged between the heater electrode and the sensor electrode, rectifies and smoothes the commercial frequency voltage generated at the sensor electrode, and compares it with a predetermined value. By operating the relay and controlling the supply of electricity to the heater electrode on and off by this relay, (a) the temperature of the sheet heating element becomes uneven due to partial insulation of the sheet heating element, etc. However, the average temperature can be detected and temperature control can be performed.
(ロ) 面状発熱体にピン刺し等が起きることがあつ
ても、低温時に相当する低い検出電圧が印加さ
れないようにすることにより安全性を高めるこ
とができる。(b) Even if a pinprick or the like occurs in the planar heating element, safety can be improved by preventing the application of a low detection voltage corresponding to a low temperature.
(ハ) センサ電極の両端を接続してループ構成とし
ているので、冗長性が高く、断線による誤動作
の発生を軽減することができる。(c) Since both ends of the sensor electrode are connected to form a loop configuration, redundancy is high and malfunctions due to disconnection can be reduced.
(ニ) 単一の交流信号のみで温度制御を行いうるの
で、従来のように、不要信号の除去を必要とし
ないので、回路の大幅な簡略化を図り、コスト
ダウンを行うことができる。(d) Since temperature control can be performed using only a single alternating current signal, there is no need to remove unnecessary signals as in the past, so the circuit can be significantly simplified and costs can be reduced.
等の効果を有する。It has the following effects.
第１図は従来の温度制御回路を示す回路構成
図、第２図は第１図の主要部の等価回路図、第３
図は本発明で用いられる面状発熱体の構成図、第
４図は本発明の一実施例を示す回路構成図であ
る。
１……商用電源、２……面状発熱体、２ａ……
ヒータ電極、２ｂ……センサ電極、２ｃ……反射
電極、２ｄ……感熱材、３……平滑回路、４……
スイツチング回路、５……過昇防止回路、６……
オフ時間タイマ、７……漏電検出回路、８……リ
レー駆動回路、９……電源回路、S1，S2……リレ
ー接点。
Figure 1 is a circuit configuration diagram showing a conventional temperature control circuit, Figure 2 is an equivalent circuit diagram of the main parts of Figure 1, and Figure 3 is an equivalent circuit diagram of the main parts of Figure 1.
The figure is a block diagram of a planar heating element used in the present invention, and FIG. 4 is a circuit block diagram showing an embodiment of the present invention. 1... commercial power supply, 2... planar heating element, 2a...
Heater electrode, 2b...Sensor electrode, 2c...Reflecting electrode, 2d...Heat-sensitive material, 3...Smoothing circuit, 4...
Switching circuit, 5... Overheating prevention circuit, 6...
Off-time timer, 7...Earth leakage detection circuit, 8...Relay drive circuit, 9...Power supply circuit, S1 , S2 ...Relay contact.
Claims (1)
置されたヒータ電極とループ状に形成されたセン
サ電極とを有し、かつ前記ヒータ電極とセンサ電
極との間に複数の分割された反射電極を配設した
面状発熱体を備え、前記センサ電極に生じる商用
周波電圧を整流・平滑し、所定値と比較してリレ
ーを動作せしめ、このリレーにより前記ヒータ電
極への通電をオン・オフ制御してなる温度制御回
路。1 A heater electrode and a loop-shaped sensor electrode are arranged in the forward and return paths through a heat-sensitive material, and a plurality of divided sections are formed between the heater electrode and the sensor electrode. It is equipped with a planar heating element provided with a reflective electrode, rectifies and smoothes the commercial frequency voltage generated at the sensor electrode, and compares it with a predetermined value to operate a relay, which turns on and off the electricity to the heater electrode. Temperature control circuit with off control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17940583A JPS6072010A (en) | 1983-09-29 | 1983-09-29 | Temperature controlling circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17940583A JPS6072010A (en) | 1983-09-29 | 1983-09-29 | Temperature controlling circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6072010A JPS6072010A (en) | 1985-04-24 |
| JPH0318203B2 true JPH0318203B2 (en) | 1991-03-12 |
Family
ID=16065289
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17940583A Granted JPS6072010A (en) | 1983-09-29 | 1983-09-29 | Temperature controlling circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6072010A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6194121A (en) * | 1984-10-15 | 1986-05-13 | Matsushita Electric Works Ltd | Temperature control circuit |
| JPH0782398B2 (en) * | 1985-07-17 | 1995-09-06 | 松下電工株式会社 | Heater temperature control circuit |
| JPS6222118A (en) * | 1985-07-23 | 1987-01-30 | Matsushita Electric Works Ltd | Control circuit for temperature of heater |
| JPS63181284A (en) * | 1987-01-22 | 1988-07-26 | 松下電工株式会社 | Heater |
| JP2590509B2 (en) * | 1988-02-01 | 1997-03-12 | 松下電器産業株式会社 | Temperature control device |
| JP2517043B2 (en) * | 1988-02-10 | 1996-07-24 | 松下電器産業株式会社 | Temperature control device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5340321U (en) * | 1976-09-08 | 1978-04-07 |
-
1983
- 1983-09-29 JP JP17940583A patent/JPS6072010A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5340321U (en) * | 1976-09-08 | 1978-04-07 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6072010A (en) | 1985-04-24 |
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