JPS59135026A - Rice cooker - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 乙の発明は、内釜内の米飯の沸騰点を検出して、それを
境にそれまでの強火加熱から中火加熱に加熱制御を行う
ことのできる炊飯器に関するものである。[Detailed description of the invention] The invention of B relates to a rice cooker that can detect the boiling point of cooked rice in the inner pot and control the heating from high heat heating to medium heat heating at that point. It is.

従来の炊飯器おいては、内釜の側面や底面の温度検出に
よって、内釜内の米飯の沸騰点を検出し、それによって
炊飯加熱制御が行われていｔコが、内釜の側面や底面は
近くに炊飯ヒータがあるため、周囲温度がずれたり、又
温度検出器と内釜の密着が悪いと沸騰点がずれたり、又
温度特性自体も不安定なため正確な沸騰点が検出できな
いという問題があった。In conventional rice cookers, the boiling point of the rice in the inner pot is detected by detecting the temperature on the side and bottom of the inner pot, and rice cooking heating control is performed accordingly. Because there is a rice cooker nearby, the ambient temperature may deviate, or the boiling point may deviate if the temperature sensor and the inner pot are not in close contact, and the temperature characteristics themselves are unstable, making it impossible to accurately detect the boiling point. There was a problem.

この発明はかかる問題を改善す石ためになされたもので
、内フタ温度検出器により予め定められた温度を検出し
た後に、各炊飯量に応じた時間が経過してからそれまで
の強火加熱から中尺 矢加熱に炊飯加熱制御する乙とにより、最適な炊飯加熱
制御をし得る炊飯器を提案す逮ものである。This invention was made to improve this problem, and after a predetermined temperature is detected by the inner lid temperature detector, a period of time corresponding to the amount of rice to be cooked has elapsed, and then the heating is started over high heat until then. This article proposes a rice cooker that can optimally control the heating of rice by controlling the heating of rice during medium heating.

第１図は本発明による炊飯器本体の断面図である。FIG. 1 is a sectional view of the rice cooker main body according to the present invention.

図中、１は外釜で、その中に米と水が入る内釜５が配置
されている。８は外フタであり、中に内フタ９の温度を
検出する内フタ温度検出器３がスプリング８０により下
方に付勢されて内フタ９に圧接されている。In the figure, 1 is an outer pot, and an inner pot 5 in which rice and water are placed is arranged. Reference numeral 8 denotes an outer lid, in which an inner lid temperature detector 3 for detecting the temperature of the inner lid 9 is urged downward by a spring 80 and is pressed against the inner lid 9.

６は外釜１内の底部に配設された炊飯ヒータ、８１は内
釜５の中央部底面に密着するように配置された底温度検
出器である。6 is a rice cooking heater disposed at the bottom of the outer pot 1, and 81 is a bottom temperature detector disposed in close contact with the bottom surface of the central portion of the inner pot 5.

第２図は本発明による炊飯器の一実施例の全体構成図で
ある。FIG. 2 is an overall configuration diagram of an embodiment of the rice cooker according to the present invention.

この実施例は第２図４）ら明らかなように、内釜５を底
部から加熱する炊飯ヒータ６と、内釜５の上面開口を覆
う内フタ９の温度を検出する内フタ温度検出器３を設け
、この内フタ温度検出＃３の検出信号に基づき炊飯量判
定手段１９で内釜５内の炊飯量を判定し、この判定に基
づき以後の加熱量を炊飯加熱量決定手段２０によって決
定し、乙の決定手段２０の出力に基づいて炊飯ヒータ６
の加熱量を加熱量制御手段２１により制御するように構
成されている。As is clear from FIG. 2 4), this embodiment includes a rice cooking heater 6 that heats the inner pot 5 from the bottom, and an inner lid temperature detector 3 that detects the temperature of the inner lid 9 that covers the top opening of the inner pot 5. Based on the detection signal of the inner lid temperature detection #3, the rice cooking amount determination means 19 determines the amount of rice cooked in the inner pot 5, and based on this determination, the subsequent heating amount is determined by the rice heating amount determination means 20. , the rice cooking heater 6 based on the output of the determining means 20 of
The heating amount is controlled by the heating amount control means 21.

また前記内フタ温度検出器３の検出信号に基づき沸騰点
判定手段２２で沸騰点を判定し、乙の判定に基づき計時
手段２３で所定の時間を計時した後に前記加熱量制御手
段２１がそれまでの強火加熱に加熱量を切換えるように
構成されている。Further, the boiling point determination means 22 determines the boiling point based on the detection signal of the inner lid temperature detector 3, and after the timer means 23 measures a predetermined time based on the determination of B, the heating amount control means 21 It is configured to switch the heating amount to high heat heating.

第３図は第１図の一実施例の電気接続を示す回路図であ
り、５６はＡ／Ｄ変換藷３９、メモリ４０、ＣＰＵ４１
、入力回路３８、出力回路４３を内蔵するマイクロコン
ピュータ４２を含む制御装置である。FIG. 3 is a circuit diagram showing the electrical connections of the embodiment shown in FIG.
, an input circuit 38 , and an output circuit 43 .

２４．２５は温度検出器３，８１にそれぞれ直列な抵抗
であり、それぞれの検出出力ζよマイクロコンピュータ
４２のＡ／Ｄ変換器３９を経て入力回路３８に入力され
る。24 and 25 are resistors connected in series with the temperature detectors 3 and 81, respectively, and the respective detection outputs ζ are inputted to the input circuit 38 via the A/D converter 39 of the microcomputer 42.

３５．３６，３７は内釜検出スイ、ツチ１６、炊飯スイ
ッチ１７、テストスイッチ３４（こ直列す抵抗であり、
その出力はマイクロコンピュータ４２内の入力回路３８
に入力される。35. 36 and 37 are the inner pot detection switch, the switch 16, the rice cooking switch 17, and the test switch 34 (resistors connected in series).
Its output is input to the input circuit 38 in the microcomputer 42.
is input.

加熱量制御手段２１は炊飯ヒータ６と直列な双方向サイ
リスタ５２、抵抗４８、トランジスタ４９及び抵抗４４
を有し、出力回路４３（こ接続されている。５１は加熱
用交流電源である。The heating amount control means 21 includes a bidirectional thyristor 52, a resistor 48, a transistor 49, and a resistor 44 in series with the rice cooking heater 6.
It has an output circuit 43 (this is connected to it. 51 is a heating AC power supply.

次に、上記実施例の動作を説明する。Next, the operation of the above embodiment will be explained.

第４図はマイクロコンピュータ４２のメモ嘗〕４０に記
憶された炊飯プログラムを示すフローチャートである。FIG. 4 is a flowchart showing the rice cooking program stored in the memo 40 of the microcomputer 42.

電源を投入すると、マイクロコンピュータ４２が起動し
、始め、まず炊飯エイ１．チ１フカ９押されてステップ
６６で炊飯モード判定がなされると、ステップ６７にお
いて、炊飯電力カタ最大尤こ設定され、内フタ温度が１
＋　（例え（ｆ４０℃）より高くなるのなまっている（
ステップ６８）。内フタ温度がｔｌより高くなってから
、次にｔ３（例えば５５℃）になるまでの時間Ｔ、をマ
イクロコンピュータ４２はカウントし、そのカウント時
間Ｔ０によって炊飯量を自動判定する（ステップ７０）
。When the power is turned on, the microcomputer 42 starts up and starts cooking rice 1. When the rice cooking mode is determined in step 66 by pressing the button 1, the rice cooking power level is set to the maximum and the inner lid temperature is set to 1 in step 67.
＋ (Example: f=40℃).
Step 68). The microcomputer 42 counts the time T from when the inner lid temperature becomes higher than tl until it reaches t3 (for example, 55°C), and automatically determines the amount of cooked rice based on the counted time T0 (step 70).
.

従来の炊飯器は、内釜の側面や底面の温度を検出する温
度検出器の温度上昇率によって炊飯量を判定していたが
、この方法では温度検出器のすぐ近くに炊飯ヒータ６が
高温に発熱しているｔコめ、温度検出器の周囲温度が高
く、温度検出器と内釜の側面又は底面の接触のバラツキ
の影響を大きく受ける。すなわち接触面積の小さいとき
は温度検出器と内釜との間で大きな温度匂配が生じ、実
際の温度上昇よりも急勾配を描くが、逆に接触面積が大
きいと温度匂配は穏やかになる。Conventional rice cookers determine the amount of cooked rice based on the temperature rise rate of a temperature sensor that detects the temperature of the sides and bottom of the inner pot. When the heat is generated, the ambient temperature of the temperature sensor is high, and it is greatly affected by variations in the contact between the temperature sensor and the side or bottom of the inner pot. In other words, when the contact area is small, a large temperature gradient occurs between the temperature detector and the inner pot, and the slope is steeper than the actual temperature rise, but conversely, when the contact area is large, the temperature gradient becomes gentler. .

従って炊飯量の判定にも誤差を生じる欠点を持っている
。しかるに本発明では近くに高温発熱体のないフタ部に
設けた内フタ扁度検出Ｎ３が内フタ９の温度上昇を検出
することによって炊飯量を判定するため、そもそも内フ
タ温度検出器３と内フタ９の温度匂配が小さく、それら
の接触面積が変化したとしても大きな影響は受けない。Therefore, it has the disadvantage of causing errors in determining the amount of rice to be cooked. However, in the present invention, since the inner lid flatness detector N3 provided in the lid part that does not have a high-temperature heating element nearby determines the amount of rice cooked by detecting the temperature rise of the inner lid 9, the inner lid temperature detector 3 and the inner lid are connected in the first place. The temperature distribution of the lid 9 is small, and even if the contact area between them changes, it will not be affected greatly.

従って、内フタ温度検出器３の匂配により炊飯量を判定
することにより、炊飯量判定の信頼性が著しく向上でき
る。Therefore, by determining the amount of cooked rice based on the scent of the inner lid temperature detector 3, the reliability of determining the amount of cooked rice can be significantly improved.

本発明は、内フタ９の温度だけでなく、内釜５内から発
生する水蒸気の温度を直接検出したり、もっと他のツク
の部品温度を検出しても同じ効果が得られることはいう
までもない。It goes without saying that the present invention can achieve the same effect by directly detecting not only the temperature of the inner lid 9 but also the temperature of the steam generated from within the inner pot 5, or by detecting the temperature of other components. Nor.

第４図と第５図でさらに炊飯過程を説明すると、内フタ
温度がｔｊに達すると（ステップ６９）炊飯量判定が終
わり　（ステップ７０）、炊飯量に応じた強火電力に炊
飯ヒータ６を制御しくステップ７１）、内フタ温度がｔ
４（例えば８２℃）に達するまでは強火電力制御を続け
ろ（ステ、。To further explain the rice cooking process with reference to FIGS. 4 and 5, when the inner lid temperature reaches tj (step 69), the amount of rice to be cooked is determined (step 70), and the rice cooking heater 6 is controlled to a high power level according to the amount of rice to be cooked. In step 71), the inner lid temperature reaches t.
Continue high heat power control until the temperature reaches 4 (e.g. 82℃).

プ７２）。この温度ｔ４は、内釜５内の米と水の温度が
上がり、やがて沸騰を始めるが、乙の沸騰点を検出する
ための温度である。72). This temperature t4 is a temperature for detecting the boiling point of rice and water in the inner pot 5, which will rise in temperature and eventually start boiling.

炊飯はお米に十分吸水させた後、炊きムラが生じないよ
う一気に強火加熱し、沸騰してからはふきこぼれを起こ
さず、かつご飯の温度が下がらない程度の中火加熱に減
じて炊き上げるのが良いとされている。When cooking rice, it is best to let the rice absorb enough water, then heat it all at once over high heat to avoid uneven cooking, and once it has boiled, reduce the heat to medium enough to prevent the rice from boiling over and the temperature of the rice to drop. It is said to be good.

しかし、沸騰前に火力を弱めると、内釜内のご飯の温度
が下がり、場所によっては温度が上がりきらず、米澱粉
の糊化が十分に行われない不具合を生ずる。However, if the heat is weakened before the rice boils, the temperature of the rice in the inner pot will drop, and in some places the temperature will not rise completely, causing problems such as insufficient gelatinization of rice starch.

従来のように内釜５の底部や側面の温度を検出する方法
では、温度特性として米飯が沸騰する点を明瞭に検出す
る特徴がはっきりしておらず、又温度検出器と内釜との
接触面積がバラツクと、温度検出器の温度上昇曲線が変
化する等の理由で、常に米飯の沸騰点を正確につかむこ
とは難かしかった。In the conventional method of detecting the temperature at the bottom or side of the inner pot 5, the temperature characteristics that clearly detect the boiling point of cooked rice are not clear, and the temperature sensor and the inner pot are not in contact with each other. It was difficult to always accurately determine the boiling point of rice due to variations in area and changes in the temperature rise curve of the temperature detector.

しかしながら本発明によれば、内フタ温度検出器３は内
フタ９に密着して、内フタ９の温度を検出しており、こ
の内フタ９は内釜５に密着して内釜５の温度を拾うと同
時に、内釜５から蒸発してくる水蒸気を直接受けるため
、温度上昇をより確実に検出する乙とができる。However, according to the present invention, the inner lid temperature detector 3 is in close contact with the inner lid 9 to detect the temperature of the inner lid 9, and the inner lid 9 is in close contact with the inner pot 5 to detect the temperature of the inner pot 5. At the same time as the water vapor is picked up, the water vapor evaporating from the inner pot 5 is directly received, making it possible to detect the temperature rise more reliably.

第５図において、内フタ温度検出器３の温度が坏に達し
てから、本発明ではさらに炊飯量に応じて中火加熱に電
力を減するまでの遅延時間ＴＩをマイクロコンピュータ
４２が計時しくステップ７３）、火力コントロールして
いる（ステップ７４）。In FIG. 5, in the present invention, the microcomputer 42 measures the delay time TI from when the temperature of the inner lid temperature detector 3 reaches the lowest temperature until the electric power is further reduced to medium heat heating according to the amount of rice cooked. 73), and the firepower is controlled (step 74).

乙の電は実験により求められる経験的なデータであるが
、一般に炊飯量が多いとＴ、は大きくなる。The electric power of Otsu is empirical data obtained through experiments, but in general, the larger the amount of rice cooked, the larger T becomes.

炊飯動作が進み、内釜５内の底部に水がなくなって内釜
底部の温度が急上昇し、その底部温度がｔ４（例えば１
２５℃）に達すると、底温度検出器８１からの出力によ
り、マイクロコンピュータ４２内で所定値を越えたと判
定され、トランジスタ４９がオフ状態となり、双方向サ
イリスタ５２がオフ状態を保つようになって炊飯が完了
する（ステップ７６）。As the rice cooking operation progresses, water runs out at the bottom of the inner pot 5, and the temperature at the bottom of the inner pot rises rapidly.
25° C.), the microcomputer 42 determines that the predetermined value has been exceeded based on the output from the bottom temperature detector 81, the transistor 49 is turned off, and the bidirectional thyristor 52 is kept in the off state. The rice cooking is completed (step 76).

以上のように本発明によれば、内フタ温度を検出して炊
飯量及び沸騰点を判定するようにし、ひの判定に基づい
て適切な加熱量を与え得るように構成したので、炊飯量
や沸騰点を誤判定する等の不都合を′回避でき、適切な
加熱量でおいしいご飯を炊くことができる。また強火加
熱から中火加熱へ加熱量を切り換える際に遅延時間を設
けているから、確実に沸騰点をつかむことができ、接触
面積のバラツキなどの影響を受けることない。As described above, according to the present invention, the amount of cooked rice and the boiling point are determined by detecting the inner lid temperature, and the appropriate amount of heating can be given based on the determination of the temperature. Inconveniences such as misjudging the boiling point can be avoided, and delicious rice can be cooked with an appropriate amount of heat. In addition, since a delay time is provided when switching the heating amount from high heat heating to medium heat heating, the boiling point can be determined reliably and is not affected by variations in contact area.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明による炊飯器本体の断面図、第２図は本
発明による炊飯器の一実施例の全体構成図、第３図はそ
の電気接続を示す回路図、第４図はその動作を示すフロ
ーチャート、第５図は本発明による炊飯器の一実施例の
動作説明用線図である。 ５は内釜、３は内フタ温度検出器、６は炊飯ヒータ、８
は底温度検出器、４２はマイクロコンピュータ、１９は
炊飯量判定手段、２０は炊飯量加熱決定手段、２１は加
熱制御手段、２２は沸騰点判定手段、２３は計時手段で
ある。 代理人　葛　野　信　−（外１名） 牙１図 第４図 牙５図 賜　　間　　　　−−＋Figure 1 is a sectional view of the rice cooker main body according to the present invention, Figure 2 is an overall configuration diagram of an embodiment of the rice cooker according to the present invention, Figure 3 is a circuit diagram showing its electrical connections, and Figure 4 is its operation. FIG. 5 is a diagram for explaining the operation of an embodiment of the rice cooker according to the present invention. 5 is the inner pot, 3 is the inner lid temperature detector, 6 is the rice cooker, 8
1 is a bottom temperature detector, 42 is a microcomputer, 19 is a rice cooking amount determining means, 20 is a cooking rice amount heating determining means, 21 is a heating control means, 22 is a boiling point determining means, and 23 is a clocking means. Agent Shin Kuzuno - (1 other person) Fang 1 figure 4 Fang 5 figure Ma - - +

Claims (2)

【特許請求の範囲】[Claims] （１）　　内釜を底部から加熱する炊飯ヒータ、前記内
釜の上面を覆う内フタ、この内フタの温度を検出する内
フタ温度検出器、この内フタ高度検出器の検出信号を入
力とし、所定温度帯域を通過する際の所要時間を測定し
て炊飯量を判定する炊飯量判定手段、この炊飯量判定手
段によって判定された炊飯量に基づき以後の加熱量を決
定する炊飯加熱量決定手段、倹牽前記炊飯加熱量決定手
段の出力に基づき前記炊飯ヒータの加熱量を制御する加
熱量制御手段、前記内フタ温度検出器の検出信号を入力
として米飯の沸騰点を判定する沸騰点判定手段、及びこ
の判定手段による沸騰点判定後に所定時間を計時する計
時手段を備え、とのＭ計時手段からの計時完了出力に基
づいて前記加熱量制御手段はそれまでの強火加熱から中
火加熱に加熱量を切換えるようにしたことを特徴とする
炊飯器。(1) A rice cooking heater that heats the inner pot from the bottom, an inner lid that covers the top surface of the inner pot, an inner lid temperature detector that detects the temperature of this inner lid, and a detection signal from this inner lid altitude detector are input, A rice cooking amount determining means that determines the amount of cooked rice by measuring the time required to pass through a predetermined temperature range, a rice cooking heating amount determining means that determines the amount of subsequent heating based on the amount of cooked rice determined by the rice cooking amount determining means, heating amount control means for controlling the heating amount of the rice cooking heater based on the output of the rice cooking heating amount determining means; boiling point determining means for determining the boiling point of the cooked rice by inputting a detection signal from the inner lid temperature detector; and a timer for timing a predetermined time after the boiling point has been determined by the determination means, and the heating amount control means changes the amount of heating from high heat heating to medium heat heating based on the timing completion output from the M timer. A rice cooker characterized by being configured to switch between. （２）炊飯量判定手段、炊飯加熱量決定手段、沸騰点判
定手段、及び計時手段がマイクロコンピュータで実現さ
れている特許請求の範囲第１項記載の炊飯器。(2) The rice cooker according to claim 1, wherein the rice cooking amount determining means, the cooking rice heating amount determining means, the boiling point determining means, and the time measuring means are implemented by a microcomputer.