JP3012953B2 - Electric water heater - Google Patents
Electric water heaterInfo
- Publication number
- JP3012953B2 JP3012953B2 JP4091294A JP9129492A JP3012953B2 JP 3012953 B2 JP3012953 B2 JP 3012953B2 JP 4091294 A JP4091294 A JP 4091294A JP 9129492 A JP9129492 A JP 9129492A JP 3012953 B2 JP3012953 B2 JP 3012953B2
- Authority
- JP
- Japan
- Prior art keywords
- heating
- water
- temperature
- change rate
- temperature change
- 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 - Fee Related
Links
Landscapes
- Cookers (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は、一般家庭において水を
沸かして保温する電気湯沸かし器に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater that keeps water warm in ordinary households.
【0002】[0002]
【従来の技術】近年、水を沸かして保温する電気湯沸か
し器は、一度に多くの量の水を短時間で沸騰させ保温で
きる事が求められている。2. Description of the Related Art In recent years, an electric water heater that heats water by boiling water has been required to be able to boil a large amount of water at a time in a short time and keep the temperature.
【0003】従来の、この種の電気湯沸かし器を図6を
参照して説明する。図6において有底筒状の容器1は水
を収容し、この容器1内に収容された水を第1の加熱手
段2および第1の加熱手段2よりも加熱電力の小さい第
2の加熱手段3により加熱する。温度検知手段4は容器
1の外底部に取り付けられた感温素子4aの出力をA/
D変換器4bによりA/D変換することにより容器1内
に収容された水の温度検知を行なう。温度変化率演算手
段5は温度検知手段4の出力を入力とし容器1内に収容
された水の温度の変化率の演算を行なう。温度変化率比
較手段6は温度変化率演算手段5の出力を入力とし水の
温度変化率と所定の温度変化率との比較を行い、加熱制
御手段7は温度変化率比較手段6の出力を入力とし第1
の加熱手段2および第2の加熱手段3の通電の制御を行
う。湯沸かし時間を短縮するために加熱制御手段7は湯
沸かしを開始すると第1の加熱手段2および第2の加熱
手段3へ同時に通電する。また、容器が空のまま加熱さ
れないように、温度変化率比較手段6の出力により水の
温度変化率が所定の温度変化率よりも小さい間は加熱手
段への通電を継続し、水の温度変化率が所定の温度変化
率よりも大きくなると、第1の加熱手段2および第2の
加熱手段3への通電を停止するようになっていた。A conventional electric water heater of this type will be described with reference to FIG. In FIG. 6, a bottomed cylindrical container 1 stores water, and the water stored in the container 1 is supplied to a first heating unit 2 and a second heating unit having a smaller heating power than the first heating unit 2. Heat with 3. The temperature detecting means 4 outputs the output of the temperature sensing element 4a attached to the outer bottom of the container 1 to A /
The temperature of the water contained in the container 1 is detected by performing A / D conversion by the D converter 4b. The temperature change rate calculation means 5 receives the output of the temperature detection means 4 as input and calculates the change rate of the temperature of the water contained in the container 1. The temperature change rate comparison means 6 receives the output of the temperature change rate calculation means 5 as an input, compares the temperature change rate of water with a predetermined temperature change rate, and the heating control means 7 receives the output of the temperature change rate comparison means 6 as an input. And the first
Of the heating means 2 and the second heating means 3 are controlled. In order to shorten the time for boiling water, the heating control means 7 simultaneously supplies electricity to the first heating means 2 and the second heating means 3 when the heating is started. In addition, the output of the temperature change rate comparing means 6 keeps energizing the heating means so long as the temperature change rate of the water is smaller than the predetermined temperature change rate so that the container is not heated while being empty. When the rate becomes larger than a predetermined rate of temperature change, the power supply to the first heating means 2 and the second heating means 3 is stopped.
【0004】また図5は、サーミスタ4aの検知温度お
よび容器1の底の温度を示した図であり、横軸に加熱を
開始してからの経過時間、縦軸にその時の温度をとった
ものである。湯沸かし開始から第1の加熱手段2および
第2の加熱手段3を通電する場合には、容器1の底の温
度はすぐに上昇を開始するが、サーミスタ4aの検知温
度は通電開始からT1を経過してから上昇を開始するた
め、温度変化率比較手段の出力により加熱手段への通電
を停止しても容器1の底の温度がK1(普通400℃以
上の高温)まで上昇する。FIG. 5 is a diagram showing the detected temperature of the thermistor 4a and the temperature at the bottom of the container 1, wherein the horizontal axis indicates the elapsed time from the start of heating, and the vertical axis indicates the temperature at that time. It is. When the first heating means 2 and the second heating means 3 are energized from the start of water heating, the temperature at the bottom of the container 1 starts to rise immediately, but the detected temperature of the thermistor 4a passes T1 from the start of energization. After that, the temperature at the bottom of the container 1 rises to K1 (usually a high temperature of 400 ° C. or more) even if the power supply to the heating means is stopped by the output of the temperature change rate comparing means.
【0005】[0005]
【発明が解決しようとする課題】このような従来の電気
湯沸かし器では、感温素子4aの出力は熱応答遅れがあ
るにもかかわらず、湯沸かし時間を短くするために電力
を大きくした加熱手段で始めから加熱していたので、感
温素子4aの出力が立ち上がって、温度変化率比較手段
6の出力により水の温度変化率が所定の温度変化率より
大きいと判断し、第1の加熱手段2および第2の加熱手
段3への通電を停止しても、それまでに供給された電力
が大きいので通電停止後の容器1の温度上昇が大きくな
り容器および感温素子部が変形したり、容器内底部が変
色したりするという問題があった。In such a conventional electric water heater, although the output of the temperature sensing element 4a has a delay in thermal response, it starts with a heating means having an increased electric power in order to shorten the water heating time. , The output of the temperature sensing element 4a rises, and the output of the temperature change rate comparing means 6 determines that the temperature change rate of the water is greater than the predetermined temperature change rate. Even if the power supply to the second heating means 3 is stopped, the power supplied so far is large, so that the temperature rise of the container 1 after the power supply is stopped becomes large, and the container and the temperature-sensitive element portion are deformed, There was a problem that the bottom was discolored.
【0006】本発明は上記問題を解決することを課題と
するもので、容器1内に水がないまま加熱をした場合で
も容器1の温度上昇を小さくし容器および感温素子部の
熱変形や変色を抑えることができる優れた電気湯沸かし
器を提供することを目的としている。SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problem. Even when heating is performed without water in the container 1, the temperature rise of the container 1 is reduced to reduce the thermal deformation of the container and the temperature-sensitive element. An object of the present invention is to provide an excellent electric water heater capable of suppressing discoloration.
【0007】[0007]
【課題を解決するための手段】本発明は前記の課題を解
決するために、第一の発明として水を収容する容器と、
前記容器内に収容された水を加熱する第1の加熱手段
と、前記第1の加熱手段よりも加熱電力の小さい第2の
加熱手段と、前記第1の加熱手段および第2の加熱手段
の制御を行う加熱制御手段と、前記容器内に収容された
水の温度を検知する温度検知手段と、前記温度検知手段
の出力により前記容器内に収容された水の温度の変化率
を演算する温度変化率演算手段と、前記温度変化率演算
手段の出力を入力とし収容した水の温度変化率と所定の
温度変化率との比較を行う温度変化率比較手段と、湯沸
かしを開始してから所定の時間の計時を行う計時手段と
を備え、前記加熱制御手段は、前記計時手段により湯沸
かし開始から所定の時間が計時されている間は第2の加
熱手段のみを通電し、その間に水の温度変化率が所定の
温度変化率よりも大きくなれば第2の加熱手段への通電
を停止し、水の温度変化率が所定の温度変化率よりも小
さければ所定の時間経過後は第1の加熱手段のみに通電
または第1の加熱手段および第2の加熱手段の両方に通
電する構成としたものである。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides, as a first invention, a container for containing water;
A first heating unit for heating the water contained in the container, a second heating unit having a lower heating power than the first heating unit, and a first heating unit and a second heating unit. Heating control means for performing control; temperature detection means for detecting the temperature of water contained in the container; and temperature for calculating the rate of change of the temperature of water contained in the container based on the output of the temperature detection means. Change rate calculating means, temperature change rate comparing means for receiving the output of the temperature change rate calculating means as an input, and comparing the temperature change rate of the contained water with a predetermined temperature change rate, and a predetermined rate after starting the water heating. A heating means for counting time, wherein the heating control means energizes only the second heating means while a predetermined time has been measured from the start of boiling water by the timing means, and the temperature change of the water during that time. Rate is greater than the specified temperature change rate When the water temperature becomes lower, the power supply to the second heating means is stopped. If the temperature change rate of the water is smaller than the predetermined temperature change rate, the power supply to only the first heating means or the first heating means is performed after a predetermined time. And both the second heating means and the second heating means.
【0008】また、前記課題を解決するために第二の発
明として水を収容する容器と、前記容器内に収容された
水を加熱する第1の加熱手段および第2の加熱手段と、
前記第1の加熱手段および第2の加熱手段の制御を行う
加熱制御手段と、前記容器内に収容された水の温度を検
知する温度検知手段と、前記温度検知手段の出力により
水の温度の変化率を演算する温度変化率演算手段と、前
記温度変化率演算手段の出力を入力とし水の温度変化率
と所定の温度変化率との比較を行う温度変化率比較手段
と、湯沸かしを開始してから所定の時間の計時を行う計
時手段とを備え、前記加熱制御手段は、前記計時手段に
より湯沸かし開始から所定の時間が計時されている間は
第1の加熱手段を所定のデューティ比で通電し、その間
に水の温度変化率が所定の温度変化率よりも大きくなれ
ば第1および第2の加熱手段への通電を停止し、水の温
度変化率が所定の温度変化率よりも小さければ所定の時
間経過後は第1の加熱手段および第2の加熱手段に通電
する構成としたものである。According to a second aspect of the present invention, there is provided a container for storing water, a first heating unit and a second heating unit for heating water contained in the container.
A heating control unit that controls the first heating unit and the second heating unit; a temperature detection unit that detects a temperature of the water contained in the container; Temperature change rate calculating means for calculating a change rate; temperature change rate comparing means for receiving the output of the temperature change rate calculating means as input and comparing the temperature change rate of water with a predetermined temperature change rate; A heating means for measuring a predetermined time after the start of heating, wherein the heating control means energizes the first heating means at a predetermined duty ratio while the predetermined time is measured from the start of water heating by the time measuring means. In the meantime, if the temperature change rate of the water becomes larger than the predetermined temperature change rate, the power supply to the first and second heating means is stopped, and if the temperature change rate of the water is smaller than the predetermined temperature change rate. After a predetermined time has elapsed, the first It is obtained by a structure for energizing the heat means and the second heating means.
【0009】[0009]
【作用】第一の発明は前記した解決手段により、湯沸か
しを開始してから所定の時間は加熱電力の小さい加熱手
段のみに通電するので、感温素子の温度が上昇し始めて
から水の温度変化率を検知して通電を停止した場合で
も、容器の温度上昇を低く抑えることができ、また、所
定の時間経過後は最大電力で加熱を行うことができるの
で、短時間で湯沸かしを完了することができる。According to the first aspect of the present invention, since only the heating means having a small heating power is supplied for a predetermined time after the start of water heating, the water temperature changes after the temperature of the thermosensitive element starts to rise. Even if the power supply is stopped by detecting the rate, the temperature rise of the container can be kept low, and heating can be performed with the maximum power after the lapse of a predetermined time. Can be.
【0010】また第二の発明は前記した解決手段によ
り、湯沸かしを開始してから所定の時間は加熱電力の大
きい加熱手段を所定のデューティ比で通電するので容器
が空のまま加熱された場合は、感温素子の温度が上昇し
始めてから水の温度変化率を検知して通電を停止して
も、容器の温度上昇を低く抑えることができるので、第
一の発明と同様に熱変形や変色を防止できる。また、所
定の時間経過後は最大電力で加熱を行うので、短時間で
湯沸かしを完了することができる。According to the second aspect of the present invention, the heating means having a large heating power is energized at a predetermined duty ratio for a predetermined time after the start of water heating. Even if the temperature change rate of the water is detected after the temperature of the temperature-sensitive element starts to rise and the energization is stopped, the rise in the temperature of the container can be suppressed to a low level. Can be prevented. In addition, since the heating is performed with the maximum power after a predetermined time has elapsed, the water heater can be completed in a short time.
【0011】[0011]
(実施例1)以下、第一の発明の一実施例を図1ないし
図3を参照して説明する。なお、従来例と同じ構成のも
のは同一符号を付して説明を省略する。(Embodiment 1) An embodiment of the first invention will be described below with reference to FIGS. The same components as those in the conventional example are denoted by the same reference numerals, and description thereof is omitted.
【0012】図1において温度変化率比較手段6は第2
の加熱手段3を通電した時の所定の温度変化率と温度検
知手段4の出力から温度変化率演算手段5が求めた温度
変化率との比較を行う。計時手段8は、加熱制御手段7
が湯沸かしを開始してからの所定の時間の計時を行う計
時手段である。加熱制御手段7は、温度変化率比較手段
6および計時手段8の出力を入力として、第1の加熱手
段2および第2の加熱手段3への通電の制御を行う。本
実施例1では、第1の加熱手段2は湯沸かし時の主ヒー
タ、第2の加熱手段3は主ヒータよりも加熱電力の小さ
い保温用の補助ヒータであり、感温素子4aとしてはサ
ーミスタを使用している。また、温度変化率演算手段
5、温度変化率比較手段6、計時手段8および加熱制御
手段7はワンチップのマイクロコンピュータにより実現
している。In FIG. 1, the temperature change rate comparison means 6
A comparison is made between the predetermined temperature change rate when the heating means 3 is turned on and the temperature change rate calculated by the temperature change rate calculation means 5 from the output of the temperature detection means 4. The time keeping means 8 comprises the heating control means 7
Is a time measuring means for measuring a predetermined time from the start of water heating. The heating control means 7 controls the energization of the first heating means 2 and the second heating means 3 with the outputs of the temperature change rate comparing means 6 and the time keeping means 8 as inputs. In the first embodiment, the first heating means 2 is a main heater at the time of boiling water, the second heating means 3 is an auxiliary heater for keeping the heating power smaller than that of the main heater, and a thermistor is used as the temperature-sensitive element 4a. I'm using Further, the temperature change rate calculating means 5, the temperature change rate comparing means 6, the time keeping means 8 and the heating control means 7 are realized by a one-chip microcomputer.
【0013】上記構成において、図2を参照して本実施
例1による動作を説明すると、まず、湯沸かしを開始す
ると、ステップ101aで第2の加熱手段3への通電を
開始してステップ102へ進む。ステップ102では計
時手段8による計時を開始(リセットができる)しステ
ップ103へ進む。ステップ103ではサーミスタ4a
の出力をA/D変換器4bでA/D変換し容器1に収容
された水の温度θ1を検知し、ステップ104へ進む。
ステップ104では温度検知手段4の新しい出力を入力
として温度変化率Δθ1の演算を行いステップ105へ
進む。ステップ105では、温度変化率比較手段6によ
りステップ104で求めた水の温度変化率Δθ1と所定
の温度変化率Δθ0(本実施例1では0.5度/秒)と
の比較を4回繰り返しΔθ1とΔθ0の大小関係を確定
し、Δθ1<Δθ0であればステップ106に進み、Δ
θ1≧Δθ0であればステップ107に進む。ステップ
106では計時手段9により第2の加熱手段3への通電
を開始してからの経過時間t1の計時を行いステップ1
08へ進む。ステップ107では第1の加熱手段2およ
び第2の加熱手段3への通電を停止することにより加熱
を終了する。ステップ108ではステップ106で計時
された時間t1と湯沸かしを開始してから第2の加熱手
段のみに通電する所定の時間T0との比較が行われ、t
1<T0すなわち湯沸かしを開始してからの経過時間が
所定の時間T0よりも短かければステップ103へ戻り
温度変化率のモニタを繰り返し、t1≧T0であればス
テップ109へ進む。ステップ109では第1の加熱手
段2および第2の加熱手段3への通電を行なう。なお、
加熱手段は電気ヒーターを含むものであっても誘導加熱
線輪を含むものであってもよい。In the above configuration, the operation of the first embodiment will be described with reference to FIG. 2. First, when water heating is started, energization of the second heating means 3 is started in step 101a and the process proceeds to step 102. . In step 102, the clocking by the clocking means 8 is started (can be reset), and the process proceeds to step 103. In step 103, the thermistor 4a
The A / D converter 4b converts the output from the A / D converter into an A / D converter, detects the temperature θ1 of the water contained in the container 1, and proceeds to step 104.
In step 104, a new output of the temperature detecting means 4 is input to calculate the temperature change rate Δθ1 and the routine proceeds to step 105. In step 105, the temperature change rate Δθ1 obtained in step 104 by the temperature change rate comparison means 6 is compared with a predetermined temperature change rate Δθ0 (0.5 degrees / second in the first embodiment) four times. And Δθ0 are determined, and if Δθ1 <Δθ0, the process proceeds to step 106, where Δ
If θ1 ≧ Δθ0, the process proceeds to step 107. In step 106, the elapsed time t1 from the start of energization to the second heating means 3 by the time measuring means 9 is measured.
Proceed to 08. In step 107, the heating is terminated by stopping the current supply to the first heating means 2 and the second heating means 3. In step 108, a comparison is made between the time t1 measured in step 106 and a predetermined time T0 in which only the second heating means is energized after the water heater is started.
If 1 <T0, that is, the elapsed time from the start of water heating is shorter than the predetermined time T0, the process returns to step 103 and the monitoring of the temperature change rate is repeated. If t1 ≧ T0, the process proceeds to step 109. In step 109, the first heating means 2 and the second heating means 3 are energized. In addition,
The heating means may include an electric heater or an induction heating wire loop.
【0014】図3は、本実施例1におけるサーミスタ4
aの検知温度および容器1の底の温度を示した図であ
り、横軸に加熱を開始してからの経過時間、縦軸にその
時の温度をとったものである。水がない場合容器1の底
の温度は加熱を開始してすぐに温度上昇を始めるが、サ
ーミスタ4aの検知温度は加熱を開始してT1を経過し
てから上昇を開始する。そのため、温度検知手段4の出
力から求めた水の温度変化率Δθ1と所定の温度変化率
Δθ0を比較し容器1内に水がないことを検知して湯沸
かしを開始してからT2秒後に加熱手段への通電を停止
した場合、容器1の底の温度がK2(実施例では250
℃)まで上昇するが、従来の構成での温度上昇K1(例
えば400℃)よりも温度上昇が低いことがわかる。FIG. 3 shows the thermistor 4 according to the first embodiment.
FIG. 3 is a diagram showing the detected temperature of a and the temperature at the bottom of the container 1, in which the horizontal axis represents the elapsed time from the start of heating and the vertical axis represents the temperature at that time. When there is no water, the temperature at the bottom of the container 1 starts increasing immediately after the start of heating, but the detected temperature of the thermistor 4a starts increasing after a lapse of T1 after the start of heating. Therefore, the temperature change rate Δθ1 of water obtained from the output of the temperature detection means 4 is compared with a predetermined temperature change rate Δθ0 to detect that there is no water in the container 1 and to start water heating T2 seconds after the start of water heating. When the power supply to the container 1 is stopped, the temperature at the bottom of the container 1 becomes K2 (250 in the embodiment).
° C), but the temperature rise is lower than the temperature rise K1 (for example, 400 ° C) in the conventional configuration.
【0015】この結果、湯沸かしを開始してから所定の
時間T1までの間は第2の加熱手段3のみで加熱し、そ
の時の温度変化率を検知することにより第1の加熱手段
2の通電をするかどうかを定めるもので、例え容器内に
水がなかった場合でも容器1の温度を低く抑えることが
できる。As a result, during the period from the start of water heating to a predetermined time T1, heating is performed only by the second heating means 3, and the rate of temperature change at that time is detected, thereby energizing the first heating means 2. The temperature of the container 1 can be kept low even if there is no water in the container.
【0016】(実施例2)以下、第二の発明の一実施例
を図を参照して説明する。なお、従来例と同じ構成のも
のは同一符号を付して説明を省略する。(Embodiment 2) An embodiment of the second invention will be described below with reference to the drawings. The same components as those in the conventional example are denoted by the same reference numerals, and description thereof is omitted.
【0017】図1(第一の発明の実施例と同じであるた
め)において温度変化率比較手段8は温度検知手段4の
出力から温度変化率演算手段5が求めた温度変化率と所
定の温度変化率との比較を行う。計時手段9は、湯沸か
しを開始して第1の加熱手段を所定のデューティ比で通
電し始めてからの所定の時間の計時を行う計時手段であ
る。加熱制御手段10は、温度変化率比較手段8および
計時手段9の出力を入力として第1の加熱手段2および
第2の加熱手段3への通電の制御を行う。本実施例2で
は、第1の加熱手段2は湯沸かし時の主ヒータ、第2の
加熱手段3は主ヒータよりも加熱電力の小さい保温用の
補助ヒータであり、感温素子4aとしてはサーミスタを
使用している。また、温度変化率演算手段5、温度変化
率比較手段6、計時手段8および加熱制御手段7はワン
チップのマイクロコンピュータにより実現している。In FIG. 1 (because it is the same as that of the first embodiment), the temperature change rate comparing means 8 compares the temperature change rate obtained by the temperature change rate calculating means 5 from the output of the temperature detecting means 4 with a predetermined temperature. Compare with the change rate. The time measuring means 9 is a time measuring means for measuring a predetermined time from the start of water heating and the energization of the first heating means at a predetermined duty ratio. The heating control means 10 controls the energization of the first heating means 2 and the second heating means 3 with the outputs of the temperature change rate comparing means 8 and the time measuring means 9 as inputs. In the second embodiment, the first heating means 2 is a main heater when water is being boiled, the second heating means 3 is an auxiliary heater for keeping the heating power smaller than that of the main heater, and a thermistor is used as the temperature sensing element 4a. I'm using Further, the temperature change rate calculating means 5, the temperature change rate comparing means 6, the time keeping means 8 and the heating control means 7 are realized by a one-chip microcomputer.
【0018】上記構成において、図4を参照して本実施
例2の動作を説明すると、まず、湯沸かしを開始する
と、ステップ101bで第1の加熱手段2へ所定のデュ
ーティ比(本実施例2においては1/2デューティ)で
断続通電を開始してステップ102へ進む。ステップ1
02では計時手段8による計時を開始(リセットができ
る)しステップ103へ進む。ステップ103ではサー
ミスタ4aの出力をA/D変換器4bでA/D変換し容
器1に収容された水の温度θ1を検知し、ステップ10
4へ進む。ステップ104では温度検知手段4の新しい
出力を入力として温度変化率Δθ1の演算を行いステッ
プ105へ進む。ステップ105では、温度変化率比較
手段6によりステップ104で求めた水の温度変化率Δ
θ1と所定の温度変化率Δθ0との比較を行ない、Δθ
1<Δθ0であればステップ106に進み、Δθ1≧Δ
θ0であればステップ107に進む。ステップ106で
は計時手段9により第2の加熱手段3への通電を開始し
てからの経過時間t1の計時を行いステップ108へ進
む。ステップ107では第1の加熱手段2および第2の
加熱手段3への通電を停止することにより加熱を終了す
る。In the above configuration, the operation of the second embodiment will be described with reference to FIG. 4. First, when water heating is started, a predetermined duty ratio (in the second embodiment, (は duty), the intermittent energization is started, and the routine proceeds to step 102. Step 1
At 02, the time counting by the time counting means 8 is started (can be reset), and the routine proceeds to step 103. In step 103, the output of the thermistor 4a is A / D converted by the A / D converter 4b, and the temperature θ1 of the water contained in the container 1 is detected.
Proceed to 4. In step 104, a new output of the temperature detecting means 4 is input to calculate the temperature change rate Δθ1 and the routine proceeds to step 105. In step 105, the temperature change rate Δ of the water obtained in step 104 by the temperature change rate comparing means 6.
A comparison between θ1 and a predetermined temperature change rate Δθ0 is performed, and Δθ
If 1 <Δθ0, the process proceeds to step 106, where Δθ1 ≧ Δ
If θ0, the process proceeds to step 107. In step 106, the elapsed time t1 from the start of energization of the second heating means 3 by the time measuring means 9 is measured, and the routine proceeds to step 108. In step 107, the heating is terminated by stopping the current supply to the first heating means 2 and the second heating means 3.
【0019】ステップ108ではステップ107で計時
された時間t1と湯沸かしを開始してから第1の加熱手
段を所定のデューティ比で通電する所定の時間T0との
比較が行われ、t1<T0すなわち湯沸かしを開始して
からの経過時間が所定の時間T0よりも短ければステッ
プ103へ戻り温度変化率のモニタを繰り返し、t1≧
T0であればステップ109へ進む。ステップ109で
は第1の加熱手段2および第2の加熱手段3への通電を
行なう。In step 108, a comparison is made between the time t1 measured in step 107 and a predetermined time T0 in which the first heating means is energized at a predetermined duty ratio after the water heater is started, and t1 <T0, that is, the water heater is heated. If the elapsed time from the start of the process is shorter than the predetermined time T0, the process returns to step 103 and the monitoring of the temperature change rate is repeated, and t1 ≧
If it is T0, the process proceeds to step 109. In step 109, the first heating means 2 and the second heating means 3 are energized.
【0020】図5は、本実施例2におけるサーミスタ4
aの検知温度および容器1の底の温度を示した図であ
り、横軸に加熱を開始してからの経過時間、縦軸にその
時の温度をとったものである。水がない場合容器1の底
の温度は加熱を開始してすぐに温度上昇を始めるが、サ
ーミスタ4aの検知温度は加熱を開始してT1を経過し
てから上昇を開始する。そのため、温度検知手段4の出
力から求めた水の温度変化率Δθ1と所定の温度変化率
Δθ0を比較し容器1内に水がないことを検知して加熱
手段への通電を停止した場合、容器1の底の温度がK2
まで上昇するが、従来の構成での温度上昇K1よりも温
度上昇が低いことがわかる。FIG. 5 shows a thermistor 4 according to the second embodiment.
FIG. 3 is a diagram showing the detected temperature of a and the temperature at the bottom of the container 1, in which the horizontal axis represents the elapsed time from the start of heating and the vertical axis represents the temperature at that time. When there is no water, the temperature at the bottom of the container 1 starts increasing immediately after the start of heating, but the detected temperature of the thermistor 4a starts increasing after a lapse of T1 after the start of heating. Therefore, when the temperature change rate Δθ1 of the water obtained from the output of the temperature detection means 4 is compared with a predetermined temperature change rate Δθ0, it is detected that there is no water in the vessel 1, and the power supply to the heating means is stopped. The temperature at the bottom of 1 is K2
It can be seen that the temperature rise is lower than the temperature rise K1 in the conventional configuration.
【0021】この結果、湯沸かしを開始してから所定の
時間T1までの間は第1の加熱手段2を所定のデューテ
ィ比で通電して加熱し、その時の温度変化率を検知する
ことにより加熱手段のフル通電をするかどうかを定める
もので、例え容器内に水がなかった場合でも容器1の温
度を低く抑えることができる。As a result, the first heating means 2 is energized and heated at a predetermined duty ratio from the start of water heating to a predetermined time T1, and the rate of temperature change at that time is detected to thereby heat the first heating means 2. This determines whether or not the full energization is performed, so that the temperature of the container 1 can be kept low even if there is no water in the container.
【0022】[0022]
【発明の効果】上記実施例から明らかなように本発明に
おける第一の発明によれば、湯沸かしを開始してから所
定の時間は加熱電力を低く抑えておいて温度変化率に基
づいて容器が空であるかどうかの判断をし、所定の時間
経過後に最大電力で加熱をするので、加熱時間を短かく
するために加熱電力が大きくなった場合でも空焼き時の
容器の温度上昇を低く抑えて、熱変形や変色を防ぐこと
ができる。As is apparent from the above embodiment, according to the first aspect of the present invention, the heating electric power is kept low for a predetermined time after the start of water heating, and the container is set based on the temperature change rate. Judgment whether it is empty or not and heating with the maximum power after a predetermined time elapses, so even if the heating power becomes large to shorten the heating time, the temperature rise of the container during empty baking is kept low. Thus, heat deformation and discoloration can be prevented.
【0023】また第二の発明によれば、湯沸かしを開始
してから所定の時間は第1の加熱手段を所定のデューテ
ィ比で通電することにより、加熱電力を低く抑えておい
て温度変化率に基づいて容器が空であるかどうかの判断
をし、所定の時間経過後に最大電力で加熱をするので、
加熱時間を短くするために加熱電力が大きくなった場合
でも空焼き時の容器の温度上昇を低く抑えて、熱変形や
変色を防ぐことができる。According to the second aspect of the present invention, the first heating means is energized at a predetermined duty ratio for a predetermined time after the start of water heating, so that the heating power is kept low and the temperature change rate is reduced. Judgment whether the container is empty based on, and heating with maximum power after a predetermined time,
Even when the heating power is increased to shorten the heating time, the rise in temperature of the container during baking can be suppressed to a low level, thereby preventing thermal deformation and discoloration.
【図1】本発明の実施例1、2の電気湯沸かし器のブロ
ック構成図FIG. 1 is a block diagram of an electric water heater according to embodiments 1 and 2 of the present invention.
【図2】第一の発明の実施例1の電気湯沸かし器の加熱
制御手段の動作フローチャートFIG. 2 is an operation flowchart of heating control means of the electric water heater according to the first embodiment of the first invention;
【図3】同電気湯沸かし器の温度特性図FIG. 3 is a temperature characteristic diagram of the electric water heater.
【図4】第二の発明の実施例2の電気湯沸かし器の加熱
制御手段の動作フローチャートFIG. 4 is an operation flowchart of heating control means of the electric water heater according to the second embodiment of the second invention.
【図5】同電気湯沸かし器の温度特性図FIG. 5 is a temperature characteristic diagram of the electric water heater.
【図6】従来の電気湯沸かし器のブロック構成図FIG. 6 is a block diagram of a conventional electric water heater.
【図7】従来の電気湯沸かし器の温度特性図FIG. 7 is a temperature characteristic diagram of a conventional electric water heater.
1 容器 2 第1の加熱手段 3 第2の加熱手段 4 温度検知手段 5 温度変化率演算手段 6 温度変化率比較手段 7 加熱制御手段 8 計時手段 DESCRIPTION OF SYMBOLS 1 Container 2 1st heating means 3 2nd heating means 4 Temperature detection means 5 Temperature change rate calculation means 6 Temperature change rate comparison means 7 Heating control means 8 Clocking means
フロントページの続き (56)参考文献 特開 平2−149225(JP,A) 特開 昭60−198115(JP,A) 特開 平4−35621(JP,A) 実開 昭63−117435(JP,U) (58)調査した分野(Int.Cl.7,DB名) A47J 27/21 101 Continuation of the front page (56) References JP-A-2-149225 (JP, A) JP-A-60-198115 (JP, A) JP-A-4-35621 (JP, A) JP-A-63-117435 (JP, A) , U) (58) Field surveyed (Int. Cl. 7 , DB name) A47J 27/21 101
Claims (2)
れた水を加熱する第1の加熱手段と、前記第1の加熱手
段よりも加熱電力の小さい第2の加熱手段と、前記第1
の加熱手段および第2の加熱手段の制御を行う加熱制御
手段と、前記容器内に収容された水の温度を検知する温
度検知手段と、前記温度検知手段の出力により前記容器
内に収容された水の温度の変化率を演算する温度変化率
演算手段と、前記温度変化率演算手段の出力を入力とし
収容した水の温度変化率と所定の温度変化率との比較を
行う温度変化率比較手段と、湯沸かしを開始してから所
定の時間の計時を行う計時手段とを備え、前記加熱制御
手段は、前記計時手段により湯沸かし開始から所定の時
間が計時されている間は第2の加熱手段のみを通電し、
その間に水の温度変化率が所定の温度変化率よりも大き
くなれば第2の加熱手段への通電を停止し、水の温度変
化率が所定の温度変化率よりも小さければ所定の時間経
過後は第1の加熱手段に、または第1の加熱手段および
第2の加熱手段の両方に通電する電気湯沸かし器。A container for storing water; a first heating unit for heating water contained in the container; a second heating unit having a lower heating power than the first heating unit; First
Heating control means for controlling the heating means and the second heating means, temperature detecting means for detecting the temperature of water contained in the container, and the temperature contained in the container by the output of the temperature detecting means. Temperature change rate calculating means for calculating a change rate of water temperature; temperature change rate comparing means for receiving the output of the temperature change rate calculating means as input and comparing the temperature change rate of the contained water with a predetermined temperature change rate. And a timer means for measuring a predetermined time after starting the water heater, wherein the heating control means only controls the second heating means while the predetermined time has been measured from the start of the water heater by the timer means. Energize,
In the meantime, if the temperature change rate of the water becomes larger than the predetermined temperature change rate, the energization to the second heating means is stopped, and if the temperature change rate of the water is smaller than the predetermined temperature change rate, a predetermined time has elapsed. Is an electric kettle for supplying electricity to the first heating means or to both the first heating means and the second heating means.
れた水を加熱する第1の加熱手段および第2の加熱手段
と、前記第1の加熱手段および第2の加熱手段の制御を
行う加熱制御手段と、前記容器内に収容された水の温度
を検知する温度検知手段と、前記温度検知手段の出力に
より前記容器内に収容された水の温度の変化率を演算す
る温度変化率演算手段と、前記温度変化率演算手段の出
力を入力として水の温度変化率と所定の温度変化率との
比較を行う温度変化率比較手段と、湯沸かしを開始して
から所定の時間の計時を行う計時手段とを備え、前記加
熱制御手段は、前記計時手段により湯沸かし開始から所
定の時間が計時されている間は第1の加熱手段を所定の
デューティ比で通電し、その間に水の温度変化率が所定
の温度変化率よりも大きくなれば第1および第2の加熱
手段への通電を停止し、水の温度変化率が所定の温度変
化率よりも小さければ所定の時間経過後は第1の加熱手
段および第2の加熱手段を通電する電気湯沸かし器。2. A container for storing water, a first heating unit and a second heating unit for heating water contained in the container, and control of the first and second heating units. Temperature control means for detecting the temperature of the water contained in the container, and a temperature change for calculating a rate of change of the temperature of the water contained in the container based on the output of the temperature detection means. Rate calculation means, temperature change rate comparison means for comparing the temperature change rate of water with a predetermined temperature change rate by using the output of the temperature change rate calculation means as an input, and timing of a predetermined time after starting water heating And a heating control means for supplying electricity to the first heating means at a predetermined duty ratio while a predetermined time is being measured from the start of water heating by the time measurement means, during which time the temperature of the water is controlled. The rate of change is greater than the specified rate of temperature change When it becomes larger, the power supply to the first and second heating means is stopped, and when the temperature change rate of the water is smaller than the predetermined temperature change rate, the first heating means and the second heating means after a predetermined time have elapsed. To energize the electric water heater.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4091294A JP3012953B2 (en) | 1992-04-13 | 1992-04-13 | Electric water heater |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4091294A JP3012953B2 (en) | 1992-04-13 | 1992-04-13 | Electric water heater |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH05285044A JPH05285044A (en) | 1993-11-02 |
JP3012953B2 true JP3012953B2 (en) | 2000-02-28 |
Family
ID=14022456
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4091294A Expired - Fee Related JP3012953B2 (en) | 1992-04-13 | 1992-04-13 | Electric water heater |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3012953B2 (en) |
-
1992
- 1992-04-13 JP JP4091294A patent/JP3012953B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH05285044A (en) | 1993-11-02 |
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