JP6831350B2 - Induction heating cooker - Google Patents

Induction heating cooker Download PDF

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JP6831350B2
JP6831350B2 JP2018116604A JP2018116604A JP6831350B2 JP 6831350 B2 JP6831350 B2 JP 6831350B2 JP 2018116604 A JP2018116604 A JP 2018116604A JP 2018116604 A JP2018116604 A JP 2018116604A JP 6831350 B2 JP6831350 B2 JP 6831350B2
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top plate
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一秀 富崎
一秀 富崎
伸明 荒金
伸明 荒金
松尾 良平
良平 松尾
博紀 駒▲崎▼
博紀 駒▲崎▼
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Hitachi Global Life Solutions Inc
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Description

本発明は、誘導加熱調理器に関する。 The present invention relates to an induction cooker.

誘導加熱調理器は、結晶化ガラスやホウケイ酸ガラス等の耐熱ガラスで構成されるトッププレートの下に誘導加熱コイル(以下「加熱コイル」と略称)を設置し、これに高周波電流を流し、発生する磁界でトッププレート上に戴置された調理鍋の鍋底にうず電流を誘起し、このジュール熱で鍋を直接加熱するものである。 In an induction heating cooker, an induction heating coil (hereinafter abbreviated as "heating coil") is installed under a top plate made of heat-resistant glass such as crystallized glass or borosilicate glass, and a high-frequency current is passed through it to generate an induction heating coil. A vortex current is induced in the bottom of the cooking pot placed on the top plate by the magnetic field, and the pot is directly heated by this Joule heat.

誘導加熱調理器の鍋底の温度検出手段として、現在では応答速度が良好で加熱された鍋底から放射される赤外線をトッププレート越しに観測し、温度を検出する赤外線センサが多く使われている。この赤外線センサとしては、フォトダイオードなどの量子型、あるいはサーモパイルなどの熱型センサが使われる。この赤外線センサは加熱コイル中心空隙付近の下に配置され、鍋底から放射される赤外線をトッププレート越しに検出して鍋底温度を出力し、その出力に応じてインバータ回路出力を制御して加熱コイルを駆動して、鍋の温度を調整するものである。トッププレートに載置された鍋は、調理温度範囲(約80℃から250℃)で加熱される。 As a means for detecting the temperature of the bottom of an induction cooker, an infrared sensor that detects the temperature by observing infrared rays radiated from the bottom of the heated pot with a good response speed through the top plate is often used. As this infrared sensor, a quantum type sensor such as a photodiode or a thermal type sensor such as a thermopile is used. This infrared sensor is placed below the center gap of the heating coil, detects infrared rays radiated from the bottom of the pot through the top plate, outputs the temperature of the bottom of the pot, and controls the output of the inverter circuit according to the output to control the heating coil. It drives and regulates the temperature of the pot. The pan placed on the top plate is heated in the cooking temperature range (about 80 ° C to 250 ° C).

鍋底の温度検知は、鍋の鍋底から放射される赤外線を赤外線センサが受光し、該赤外線センサの出力電圧を検出することで検知可能である。しかし、調理鍋の鍋底で生じた赤外線を赤外線センサで受光する際の放射エネルギーは小さい。これは、トッププレートの光学特性に要因がある。トッププレートを透過する波長は1.0μmから5.0μmの幅4.0μm程度しかなく、鍋の全放射赤外線エネルギーの1〜2%しかトッププレートを透過できないためである。このため、使用する赤外線センサの感度は体温計などに用いるものと比べて1桁以上高い感度が求められる。またセンサ出力信号が小さいため、高い増幅率を有した増幅回路が必要となり、その結果、これら赤外線センサは周囲温度の変動に対して非常に敏感となる。サーモパイル型の赤外線センサは、赤外線が入射すると感熱素子の温接点側と冷接点側の温度に比例したセンサ出力電圧を生じるため、センサ周囲が急激に温度変化をする環境下では、感熱素子の温接点側と冷接点側が不均一となりセンサ出力が変動することとなる。 The temperature detection of the bottom of the pot can be detected by the infrared sensor receiving infrared rays radiated from the bottom of the pot and detecting the output voltage of the infrared sensor. However, the radiant energy when the infrared sensor receives the infrared rays generated at the bottom of the cooking pot is small. This is due to the optical properties of the top plate. This is because the wavelength transmitted through the top plate is only about 4.0 μm in width of 1.0 μm to 5.0 μm, and only 1 to 2% of the total radiated infrared energy of the pot can be transmitted through the top plate. Therefore, the sensitivity of the infrared sensor used is required to be an order of magnitude higher than that used for a thermometer or the like. Further, since the sensor output signal is small, an amplifier circuit having a high amplification factor is required, and as a result, these infrared sensors become very sensitive to fluctuations in ambient temperature. The thermopile type infrared sensor generates a sensor output voltage proportional to the temperature of the hot contact side and the cold contact side of the heat sensitive element when infrared rays are incident on it. Therefore, in an environment where the temperature around the sensor changes rapidly, the temperature of the heat sensitive element is high. The contact side and the cold contact side become non-uniform, and the sensor output fluctuates.

また、赤外線センサは、鍋の鍋底から放射される入射エネルギー1と、加熱された調理鍋からの伝熱で温められたトッププレートから放射される入射エネルギー2と、更にトッププレートと赤外線センサ間に配置された部材が誘導加熱コイルからの輻射熱で温められて放射される入射エネルギー3を受光する。鍋底の温度の検出では入射エネルギー2と入射エネルギー3は外乱となる。 Further, the infrared sensor has an incident energy 1 radiated from the bottom of the pot, an incident energy 2 radiated from a top plate heated by heat transfer from a heated cooking pot, and further between the top plate and the infrared sensor. The arranged member receives the incident energy 3 radiated by being heated by the radiant heat from the induction heating coil. In the detection of the temperature at the bottom of the pot, the incident energy 2 and the incident energy 3 become disturbances.

この課題を解決する手段として特許文献1に挙げるものがある。 As a means for solving this problem, there is one listed in Patent Document 1.

特許文献1は、周囲温度の変化を検出できるようにサーミスタを有し、調理容器の底から放射される赤外線を検出し赤外線量に比例する直流電圧を出力する第1の赤外線センサと、該第1の赤外線センサ出力を直流増幅する第1の直流増幅器と、前記調理容器の底から放射される赤外線を遮光することによって前記調理容器の底から放射される赤外線が入射されず、赤外線量に比例する直流電圧を出力する第2の赤外線センサと、前記第2の赤外線センサ出力を反転直流増幅する第2の直流増幅器と、を備えており、前記第2の直流増幅器の出力を前記第1の直流増幅器のバイアス電圧として入力し、前記第1の直流増幅器の出力を前記赤外線検出手段へ出力することで、赤外線センサ(サーモパイル)の雰囲気温度が室温の変化に追従する緩慢な変化(定常状態)や調理が行われている時の雰囲気温度の急激変化(過渡的な状態)が生じた場合でも、鍋の温度を安定して検出することができる赤外線検出手段を備え、かつ、鍋底の温度の検出精度を向上するために赤外線センサと加熱コイル間に特定の波長域の赤外線をカットする結晶化ガラス光学フィルタを配置し、トッププレートから放射され外乱となる前記入射エネルギー2の特定の波長域の赤外線を遮断する。また、トッププレートと赤外線センサ間に配置された部材(結晶化ガラス光学フィルタ31とセンサ視野筒19等)が誘導加熱コイルからの輻射熱などで温められ放射され外乱となる入射エネルギー3を低減するために赤外線センサに使用するガラス凸レンズは、光学特性が5μmショートパス特性を持つガラスで作成して、調理時に赤外線の波長域が5μm以上の低い温度帯の発せられる赤外線がサーモパイルの赤外線吸収膜に到達するのを除去している。 Patent Document 1 includes a first infrared sensor having a thermistor so as to detect a change in ambient temperature, detecting infrared rays radiated from the bottom of a cooking container, and outputting a DC voltage proportional to the amount of infrared rays. By blocking the infrared rays radiated from the bottom of the cooking container and the first DC amplifier that amplifies the infrared sensor output of 1, the infrared rays radiated from the bottom of the cooking container are not incident and are proportional to the amount of infrared rays. A second infrared sensor that outputs a DC voltage to be generated and a second DC amplifier that inverts and amplifies the output of the second infrared sensor are provided, and the output of the second DC amplifier is used as the output of the first DC amplifier. By inputting as the bias voltage of the DC amplifier and outputting the output of the first DC amplifier to the infrared detecting means, the atmospheric temperature of the infrared sensor (thermopile) changes slowly (steady state) following the change in room temperature. It is equipped with an infrared detection means that can stably detect the temperature of the pot even if a sudden change (transient state) in the atmospheric temperature occurs during cooking or cooking, and the temperature of the bottom of the pot In order to improve the detection accuracy, a crystallized glass optical filter that cuts infrared rays in a specific wavelength range is placed between the infrared sensor and the heating coil, and in the specific wavelength range of the incident energy 2 that is radiated from the top plate and becomes a disturbance. Block infrared rays. Further, in order to reduce the incident energy 3 in which the members (crystallized glass optical filter 31 and sensor viewing tube 19 and the like) arranged between the top plate and the infrared sensor are heated and radiated by radiant heat from the induction heating coil and become disturbance. The glass convex lens used for the infrared sensor is made of glass with an optical characteristic of 5 μm short pass characteristic, and infrared rays emitted in a low temperature range of 5 μm or more reach the infrared absorbing film of the thermopile during cooking. I'm removing the infrared.

特開2013−206644号公報Japanese Unexamined Patent Publication No. 2013-206644

特許文献1に示す赤外線検出手段において、使用している二つのサーモパイルの熱伝達特性のバラツキに応じたズレについて補正ができないという課題が有る。 In the infrared detecting means shown in Patent Document 1, there is a problem that it is not possible to correct the deviation according to the variation in the heat transfer characteristics of the two thermopile used.

熱伝達特性のズレは、検出素子の上が凸レンズのある鍋放射赤外線検出用のサーモパイルと遮光金属キャンで覆われた温度補償素子のサーモパイルとの相違と相互の距離によって生じるもので以下詳細に説明する。 The deviation of the heat transfer characteristics is caused by the difference between the thermopile for detecting pan-radiated infrared rays having a convex lens on the detection element and the thermopile of the temperature compensating element covered with a light-shielding metal can and the mutual distance, which will be explained in detail below. To do.

鍋放射赤外線検出用のサーモパイルと遮光金属キャンで覆われた温度補償素子のサーモパイルは、夫々独立した金属キャンと金属ステムに入れられ、それぞれが離れて設けられていることにより周囲温度ムラなどによる温度差、熱伝達の違いによる温度差によるズレが生じる課題が有る。また、鍋放射赤外線検出用のサーモパイルはガラス凸レンズを通して入射エネルギーを受光し、遮光金属キャンで覆われた温度補償素子のサーモパイルは遮光金属キャンの放射するエネルギーを受光する。ガラス凸レンズと遮光金属キャンともに周囲の温度変化の影響を受けるもので、ガラス凸レンズと遮光金属キャンの温度変化により、ガラス凸レンズと遮光金属キャンより放射される赤外線による入射エネルギーが異なる事で前述と同様に温度ズレが生じるという課題が有る。 The thermopile for detecting infrared rays emitted from the pot and the thermopile of the temperature compensating element covered with a light-shielding metal can are placed in independent metal cans and metal stems, respectively, and because they are provided separately, the temperature due to ambient temperature unevenness, etc. There is a problem that a deviation occurs due to a temperature difference due to a difference and a difference in heat transfer. Further, the thermopile for detecting the infrared radiation from the pot receives the incident energy through the glass convex lens, and the thermopile of the temperature compensating element covered with the light-shielding metal can receives the energy radiated by the light-shielding metal can. Both the glass convex lens and the light-shielding metal can are affected by the ambient temperature change, and the incident energy due to the infrared rays emitted from the glass convex lens and the light-shielding metal can differs due to the temperature change of the glass convex lens and the light-shielding metal can. There is a problem that the temperature shift occurs.

次に、鍋放射赤外線検出用のサーモパイルが受光する赤外線には、鍋の鍋底より放射される赤外線の他に、鍋の鍋底より放射される赤外線を受光するために設けた経路や経路内の部品から放射される赤外線が含まれる課題が有る。その課題の詳細を下記に説明する。 Next, the infrared rays received by the thermopile for detecting the infrared rays emitted from the pot include the infrared rays radiated from the bottom of the pot and the paths provided to receive the infrared rays emitted from the bottom of the pot and the parts in the paths. There is a problem that infrared rays emitted from are included. The details of the problem will be described below.

鍋放射赤外線検出用のサーモパイルの受光する入射エネルギーには、前述したように、調理鍋の鍋底から放射された赤外線がトッププレートと結晶化ガラス光学フィルタを透過した際に減衰した入射エネルギー1と、加熱された調理鍋からの伝熱で温められたトッププレートから放射された赤外線と、トッププレートと赤外線センサ間に配置された部材が誘導加熱コイルからの輻射熱で温められたセンサ視野筒から放射された赤外線が結晶化ガラス光学フィルタを透過して減衰した入射エネルギー2と、トッププレートと赤外線センサ間に配置された部材が誘導加熱コイルからの輻射熱で温められた結晶化ガラス光学フィルタから放射された赤外線が鍋放射赤外線検出用サーモパイルに設けられているガラス凸レンズを透過して減衰した入射エネルギー3と、ガラス凸レンズから放射された赤外線が入射する入射エネルギー4がある。 As described above, the incident energy received by the thermopile for detecting infrared rays emitted from the pot includes the incident energy 1 attenuated when the infrared rays radiated from the bottom of the pot of the cooking pot pass through the top plate and the crystallized glass optical filter. Infrared rays radiated from the top plate heated by heat transfer from the heated cooking pot and members placed between the top plate and the infrared sensor are radiated from the sensor viewing tube heated by radiant heat from the induction heating coil. The incident energy 2 in which the infrared rays were transmitted through the crystallized glass optical filter and attenuated, and the member arranged between the top plate and the infrared sensor were radiated from the crystallized glass optical filter heated by the radiant heat from the induction heating coil. There is an incident energy 3 in which infrared rays are transmitted and attenuated through a glass convex lens provided in a thermopile for detecting pan-radiated infrared rays, and an incident energy 4 in which infrared rays radiated from the glass convex lens are incident.

鍋放射赤外線検出用のサーモパイルは、鍋の温度を検出するために必要な入射エネルギー1以外の入射エネルギー2と入射エネルギー3と入射エネルギー4は不要な外乱となる。 In the thermopile for detecting the infrared rays emitted from the pan, the incident energy 2, the incident energy 3, and the incident energy 4 other than the incident energy 1 required for detecting the temperature of the pan are unnecessary disturbances.

外乱となる入射エネルギー2は結晶化ガラス光学フィルタを透過し、入射エネルギー3はガラス凸レンズを透過させることで、調理時に必要とする温度帯(約80〜350℃)以外の低い温度時に放射される5μm以上の赤外線を遮断し、入射エネルギー4は直接赤外線吸収膜へ到達することからガラス凸レンズの温度変化による放射エネルギーの変化は大きな外乱という課題がある。 The incident energy 2 that becomes a disturbance is transmitted through the crystallized glass optical filter, and the incident energy 3 is transmitted through the glass convex lens, so that it is radiated at a low temperature other than the temperature range (about 80 to 350 ° C.) required for cooking. Since infrared rays of 5 μm or more are blocked and the incident energy 4 directly reaches the infrared absorbing film, there is a problem that the change in radiant energy due to the temperature change of the glass convex lens is a large disturbance.

以上のことから、特許文献1には課題が二つある。一つ目は二個のサーモパイルの熱伝達特性のバラツキに応じたズレと、二つ目はガラス凸レンズの温度変化による放射エネルギーの変化は大きな外乱となる課題がある。 From the above, Patent Document 1 has two problems. The first is the deviation according to the variation in the heat transfer characteristics of the two thermopile, and the second is the problem that the change in radiant energy due to the temperature change of the glass convex lens becomes a big disturbance.

本発明は、調理鍋の鍋底の温度を精度よく検出する誘導加熱調理器を提供することを目的とする。 An object of the present invention is to provide an induction heating cooker that accurately detects the temperature of the bottom of a cooking pot.

本発明は、上記課題を解決するためになされたもので、調理鍋を上面に載置するトッププレートと、該トッププレートの下方に設けられ前記調理鍋を加熱するために誘導磁界を発生させる加熱コイルと、該加熱コイルに電力を供給するインバータ手段と、前記トッププレート越しに前記調理鍋の温度を検出する赤外線センサと、該赤外線センサの出力を増幅する検出回路と、該検出回路の出力に応じて前記インバータ手段の出力を制御する制御手段とを備えた誘導加熱調理器において、前記赤外線センサには、同一金属ケース内に第1の感熱素子と第2の感熱素子を備え、前記検出回路には、任意に設定される基準電位と、該基準電位を第1のバイアス入力とし前記第1の感熱素子の出力を増幅する第1の増幅器と、前記基準電位を第1のバイアス入力として前記第2の感熱素子の出力を増幅する第2の増幅器と、前記第2の感熱素子の増幅出力を第2のバイアス入力として前記第1の感熱素子の増幅出力を増幅する第3の増幅器とを備えたものである。 The present invention has been made to solve the above problems, and is a heating in which a top plate on which a cooking pot is placed on the upper surface and a heating provided below the top plate to generate an induced potential for heating the cooking pot. The coil, the inverter means for supplying electric power to the heating coil, the infrared sensor that detects the temperature of the cooking pot through the top plate, the detection circuit that amplifies the output of the infrared sensor, and the output of the detection circuit. In an induction heating cooker provided with a control means for controlling the output of the inverter means accordingly, the infrared sensor includes a first heat-sensitive element and a second heat-sensitive element in the same metal case, and the detection circuit. The reference potential is arbitrarily set, the first amplifier uses the reference potential as the first bias input to amplify the output of the first heat sensitive element, and the reference potential is used as the first bias input. A second amplifier that amplifies the output of the second heat-sensitive element, and a third amplifier that amplifies the amplified output of the first heat-sensitive element by using the amplified output of the second heat-sensitive element as a second bias input. It is prepared.

本発明によれば、調理鍋の鍋底の温度を精度よく検出する誘導加熱調理器を提供することができる。上記した以外の課題、構成及び効果は以下の実施形態の説明により明らかにされる。 According to the present invention, it is possible to provide an induction heating cooker that accurately detects the temperature of the bottom of a cooking pot. Issues, configurations and effects other than those described above will be clarified by the following description of the embodiments.

本発明に係わる誘導加熱調理器の構成を示す斜視図。The perspective view which shows the structure of the induction heating cooker which concerns on this invention. 本発明に係わる誘導加熱調理器のトッププレートを除いた上面図。Top view of the induction cooker according to the present invention excluding the top plate. 本発明に係わる誘導加熱調理器の左右の加熱コイルを主体とした鍋底温度検出手段の構成を示すブロック図。The block diagram which shows the structure of the pot bottom temperature detecting means mainly which left and right heating coils of the induction heating cooker which concerns on this invention. 本発明に係わる鍋温度検出装置の詳細を示す断面図。The cross-sectional view which shows the detail of the pot temperature detection apparatus which concerns on this invention. 本発明に係わる鍋温度検出装置の上面図。Top view of the pan temperature detector according to the present invention. 本発明に係わる赤外線センサの詳細を示す図。The figure which shows the detail of the infrared sensor which concerns on this invention. 本発明に係わる赤外線検出手段の概要を示す図。The figure which shows the outline of the infrared ray detecting means which concerns on this invention. 本発明に係わる赤外線センサの視野特性を示す図。The figure which shows the visual field characteristic of the infrared sensor which concerns on this invention. 本発明に係わるプランクの分布則による分光放射エネルギーを示す図。The figure which shows the spectral radiant energy by the distribution rule of Planck which concerns on this invention. 本発明に係わるトッププレートなどの光学特性を示す図。The figure which shows the optical property of the top plate which concerns on this invention. 本発明に係わる反射型フォトインタラプタの説明図。Explanatory drawing of the reflection type photo interrupter which concerns on this invention. 本発明の検出回路の説明図。Explanatory drawing of the detection circuit of this invention. 本発明の検出回路の別の実施例の説明図。Explanatory drawing of another embodiment of the detection circuit of this invention.

以下、図面等を用いて、本発明の実施例について説明する。以下の説明は本発明の内容の具体例を示すものであり、本発明がこれらの説明に限定されるものではない。本明細書に開示される技術的思想の範囲内において当業者による様々な変更および修正が可能であり、下記の実施例の構成を適宜組み合わせることも当初から予定している。また、本発明を説明するための全図において、同一の機能を有するものは、同一の符号を付け、その繰り返しの説明は省略する場合がある。 Hereinafter, examples of the present invention will be described with reference to the drawings and the like. The following description shows specific examples of the contents of the present invention, and the present invention is not limited to these descriptions. Various changes and modifications can be made by those skilled in the art within the scope of the technical ideas disclosed in the present specification, and it is planned from the beginning that the configurations of the following examples are appropriately combined. Further, in all the drawings for explaining the present invention, those having the same function may be designated by the same reference numerals, and the repeated description thereof may be omitted.

(実施例)
図1は誘導加熱調理器の本体1の斜視図、図2は誘導加熱調理器のトッププレート2を除いた上面図、図3は誘導加熱調理器の左右の加熱コイル3を主体とした鍋底温度検出手段の構成を示すブロック図である。
(Example)
FIG. 1 is a perspective view of the main body 1 of the induction heating cooker, FIG. 2 is a top view of the induction heating cooker excluding the top plate 2, and FIG. 3 is a pan bottom temperature mainly composed of the left and right heating coils 3 of the induction heating cooker. It is a block diagram which shows the structure of the detection means.

以下では、誘導加熱が可能な鍋置き場所が3口有る誘導加熱調理器を例に挙げ説明を行うが、本発明の適用対象はこれに限られず、中央後部の1口をラジエントヒータやハロゲンヒータ等のヒータ(加熱源)の放射熱で加熱可能な鍋置き場所であっても良く、ヒータ部が何口で構成された誘導加熱調理器でも良い。なお、被加熱物である調理鍋30は、誘導加熱に適した磁性体の鉄鍋や、非磁性体のアルミ鍋、銅鍋などである。 In the following, an induction heating cooker having three pot storage locations where induction heating is possible will be described as an example, but the application of the present invention is not limited to this, and one port at the central rear portion is a radiant heater or a halogen heater. It may be a place where a pot can be heated by the radiant heat of a heater (heating source) such as the above, or an induction heating cooker having a number of heaters. The cooking pot 30 to be heated is a magnetic iron pot suitable for induction heating, a non-magnetic aluminum pot, a copper pot, or the like.

図1において、誘導加熱調理器の本体1の上面にはトッププレート2が配置されている。トッププレート2は、耐熱性の結晶化ガラス製で構成され、調理鍋30を載置する。本実施例のトッププレート2は結晶化ガラスを例に説明するが、耐熱性に優れ誘導加熱調理器の仕様を満たすガラスであればこれに限らず、例えばホウケイ酸ガラスを使用しても良い。 In FIG. 1, a top plate 2 is arranged on the upper surface of the main body 1 of the induction heating cooker. The top plate 2 is made of heat-resistant crystallized glass, and a cooking pot 30 is placed on the top plate 2. The top plate 2 of this embodiment will be described by taking crystallized glass as an example, but the top plate 2 is not limited to this as long as it has excellent heat resistance and satisfies the specifications of the induction cooking device, and for example, borosilicate glass may be used.

トッププレート2の上面は、本体1の内部が見えないように全体を特定の意匠で塗装が施されており、調理鍋30の載置部4が印刷されている。調理鍋30の載置部4には赤外線透過窓5を設けている。赤外線透過窓5は、調理鍋30の鍋底から放射される赤外線をトッププレート2の下部へ透過するために、前記塗装を一部施さずトッププレート2の素材の状態や赤外線を透過する塗料を施したところである。 The entire upper surface of the top plate 2 is painted with a specific design so that the inside of the main body 1 cannot be seen, and the mounting portion 4 of the cooking pot 30 is printed. An infrared transmission window 5 is provided in the mounting portion 4 of the cooking pot 30. In the infrared transmitting window 5, in order to transmit infrared rays radiated from the bottom of the cooking pot 30 to the lower part of the top plate 2, the state of the material of the top plate 2 and a paint that transmits infrared rays are applied without applying the coating. I have just done it.

トッププレート2の前面側の上面には、夫々のヒータ部(図2に示す加熱コイル3)に対応した上面操作部6a、6b、6cが設けられていて、加熱コイル3の通電状態の設定や操作を行う。また、各上面操作部6a、6b、6cの近傍には、対応した上面表示部7a、7b、7cが設けられており、夫々の加熱コイル3の通電状態などを表示する。 Upper surface operation portions 6a, 6b, and 6c corresponding to the respective heater portions (heating coil 3 shown in FIG. 2) are provided on the upper surface on the front surface side of the top plate 2, and the energized state of the heating coil 3 can be set. Perform the operation. Further, corresponding upper surface display units 7a, 7b, 7c are provided in the vicinity of the upper surface operation units 6a, 6b, 6c to display the energized state of each heating coil 3.

上面操作部6aは、本体1右側の加熱コイル3の火力等の入力を行い、上面操作部6bは本体1中央後部の加熱コイル3の火力等の入力を行い、上面操作部6cは本体1左側の加熱コイル3の火力等の入力を行う。 The upper surface operation unit 6a inputs the thermal power of the heating coil 3 on the right side of the main body 1, the upper surface operation unit 6b inputs the thermal power of the heating coil 3 at the rear center of the main body 1, and the upper surface operation unit 6c inputs the thermal power of the heating coil 3 on the left side of the main body 1. Input the thermal power of the heating coil 3 and the like.

本体1の前面左部には、魚やピザ等を焼くグリル庫8が設けられており、グリル庫8は、前面が開口した箱型をしており、内部の調理庫内にシーズヒータ等の発熱体と内部の温度を検出するサーミスタが設けられ、前面部はハンドル8aが取り付けられたグリルドア8bにより塞がれている。グリルドア8bは、その裏側に受け皿が取り付けられており、調理庫内に前面開口部から出し入れ自在に収納され、受皿や、または焼網の上に魚やピザ等の食材を載せて調理する。 A grill 8 for baking fish, pizza, etc. is provided on the left side of the front surface of the main body 1, and the grill 8 has a box shape with an open front, and heat generated by a sheathed heater or the like in the internal cooking chamber. A thermistor for detecting the temperature inside the body and the inside is provided, and the front portion is closed by a grill door 8b to which a handle 8a is attached. A saucer is attached to the back side of the grill door 8b, and the grill door 8b is stored in the kitchen so as to be freely taken in and out from the front opening, and foods such as fish and pizza are placed on the saucer or a grill to cook.

本体1の前面右部には、本体1へ供給する電源の主電源スイッチ9と、グリル庫8の加熱調理条件等を入力する前面操作部10が設けられている。前面操作部10は、下方に設けられた回転軸を中心として操作パネルの上方が前面側に倒れ、操作キーが上方側に向かって露出する所謂カンガルーポケット形態のものである。 On the right side of the front surface of the main body 1, a main power switch 9 for supplying power to the main body 1 and a front operation unit 10 for inputting cooking conditions and the like of the grill storage 8 are provided. The front operation unit 10 is of a so-called kangaroo pocket type in which the upper part of the operation panel is tilted toward the front side with the rotation axis provided below as the center and the operation keys are exposed toward the upper side.

本体1内に設けたファン(図示せず)により、本体1に外気を取込む開口部(図示せず)から吸気した冷却風を本体1内に設けたインバータ基板や制御基板(図示せず)、加熱コイル3及び鍋底の温度を検出する鍋底温度検出装置20等に流して冷却する。本体1の後部には、本体1内部を冷却した冷却風を排気する排気口11が設けられている。 An inverter board or control board (not shown) provided in the main body 1 for cooling air taken in from an opening (not shown) that takes in outside air into the main body 1 by a fan (not shown) provided in the main body 1. , The heating coil 3 and the pot bottom temperature detecting device 20 for detecting the temperature of the pot bottom are passed to cool the pot. An exhaust port 11 for exhausting the cooling air that has cooled the inside of the main body 1 is provided at the rear portion of the main body 1.

図2に示すように、トッププレート2の載置部4に対応する下方には、環状に形成された加熱コイル3が本体1内上部の左右および中央後部に夫々配置されており、トッププレート2に載置された調理鍋30等を誘導加熱する。左右及び中央後部に配置された加熱コイル3のヒータ部は、夫々環状の内側加熱コイル3aと、その外側に環状の隙間3bを設けて配置された環状の外側加熱コイル3cとで構成されている。隙間3bを設ける理由は、内側加熱コイル3aと外側加熱コイル3cとで発生する磁束を分散させて、調理鍋30の温度を均一化するためである。 As shown in FIG. 2, the heating coils 3 formed in an annular shape are arranged on the left and right sides of the upper part of the main body 1 and at the rear part of the center, respectively, below the top plate 2 corresponding to the mounting portion 4. The cooking pot 30 and the like placed on the above are induced and heated. The heater portions of the heating coils 3 arranged on the left and right and the central rear portion are each composed of an annular inner heating coil 3a and an annular outer heating coil 3c arranged with an annular gap 3b provided on the outer side thereof. .. The reason for providing the gap 3b is to disperse the magnetic flux generated by the inner heating coil 3a and the outer heating coil 3c to make the temperature of the cooking pot 30 uniform.

なお、各加熱コイル3は隙間3bを設ける構成としたが、特にこれに限定されることはない。例えば内側加熱コイル3aと外側加熱コイル3cを隙間無く巻回した隙間3bの無い加熱コイル3とする構成であってもよい。 Although each heating coil 3 is configured to have a gap 3b, the present invention is not particularly limited to this. For example, the inner heating coil 3a and the outer heating coil 3c may be wound without a gap to form a heating coil 3 having no gap 3b.

図3に示すように加熱コイル3は、コイルベース12上に内側加熱コイル3aと、隙間3b、外側加熱コイル3cを設置している。また、ギャップスペーサー13が、コイルベース12の外周縁部に取り付けられた支持部材13aによりコイルベース12の外周から中心側に向けて適宜間隔を保持して設けられており、コイルベース12が複数のバネ(図示せず)によりトッププレート2方向に付勢されることにより、加熱コイル3がトッププレート2に対し略並行となり、かつ、トッププレート2に載置される調理鍋30と加熱コイル3とのギャップが一定に保持されている。 As shown in FIG. 3, the heating coil 3 has an inner heating coil 3a, a gap 3b, and an outer heating coil 3c installed on the coil base 12. Further, the gap spacer 13 is provided by a support member 13a attached to the outer peripheral edge portion of the coil base 12 so as to maintain an appropriate interval from the outer periphery of the coil base 12 toward the center side, and a plurality of coil bases 12 are provided. By being urged in the direction of the top plate 2 by a spring (not shown), the heating coil 3 is substantially parallel to the top plate 2, and the cooking pot 30 and the heating coil 3 placed on the top plate 2 The gap is kept constant.

内側加熱コイル3aと外側加熱コイル3cは、表皮効果を抑制するためリッツ線を採用していて、後述するインバータ手段54により数十kHzの高周波で数百Vの電圧が印加され、調理鍋30に対して高周波磁界を印加して調理鍋30に渦電流を発生させ、調理鍋30を自己発熱させて加熱する。 The inner heating coil 3a and the outer heating coil 3c employ litz wire in order to suppress the skin effect, and a voltage of several hundred V is applied to the cooking pot 30 at a high frequency of several tens of kHz by the inverter means 54 described later. On the other hand, a high-frequency magnetic field is applied to generate an eddy current in the cooking pot 30, and the cooking pot 30 is self-heated to be heated.

左右及び中央に配設された加熱コイル3には、サーミスタで構成された複数の温度センサ14を配置している。加熱コイル3の中心部近傍には、内側温度センサ14aがトッププレート2の下面に密着して設けられており、加熱コイル3の上方に載せられた調理鍋30の温度を、トッププレート2を介して検知する。本実施例ではトッププレート2の温度検出手段にサーミスタを用いるが、特にこれに限定されず熱電対などの検出器を用いても良い。また、同様に加熱コイル3の隙間3bには、加熱コイル3の中心から等距離で、サーミスタによって構成された外側温度センサ14b、14c(図2)が緩衝材(図示せず)を介して設けられ、トッププレート2の下面に密着することによりトッププレート2の温度を検知する。 A plurality of temperature sensors 14 composed of thermistors are arranged on the heating coils 3 arranged on the left and right and in the center. An inner temperature sensor 14a is provided in close contact with the lower surface of the top plate 2 near the center of the heating coil 3, and the temperature of the cooking pot 30 placed above the heating coil 3 is measured via the top plate 2. To detect. In this embodiment, a thermistor is used as the temperature detecting means of the top plate 2, but the present invention is not particularly limited to this, and a detector such as a thermocouple may be used. Similarly, outside temperature sensors 14b and 14c (FIG. 2) configured by thermistors are provided in the gap 3b of the heating coil 3 at equal distances from the center of the heating coil 3 via a cushioning material (not shown). The temperature of the top plate 2 is detected by being in close contact with the lower surface of the top plate 2.

なお、外側温度センサ14b、14cは、加熱コイル3の隙間3bに設ける構成としたが、特にこれに限定されることはない。例えば外側加熱コイル3cの外周近傍や、または、内側加熱コイル3aと外側加熱コイル3cを隙間無く巻回した隙間3bの無い加熱コイル3とした構成の外周近傍に設ける構成であってもよい。また、外側温度センサ14b、14cは2個に限定されることはなく、1個または2個以上であってもよい。 The outer temperature sensors 14b and 14c are provided in the gap 3b of the heating coil 3, but the present invention is not particularly limited to this. For example, it may be provided near the outer periphery of the outer heating coil 3c, or near the outer periphery of the heating coil 3 having no gap 3b in which the inner heating coil 3a and the outer heating coil 3c are wound without a gap. Further, the number of the outer temperature sensors 14b and 14c is not limited to two, and may be one or two or more.

加熱コイル3の隙間3bの下方には、鍋温度検出装置20が設置される。隙間3b下方には鍋温度検出装置20に設けた後述する図4に示す導光筒28を配置する。鍋温度検出装置20は、調理鍋30の底面から放射され、トッププレート2の赤外線透過窓5を透過し、導光筒28で導かれた赤外線を受光する。 A pan temperature detecting device 20 is installed below the gap 3b of the heating coil 3. Below the gap 3b, a light guide tube 28 shown in FIG. 4 to be described later, which is provided in the pot temperature detection device 20, is arranged. The pot temperature detecting device 20 is radiated from the bottom surface of the cooking pot 30, passes through the infrared transmitting window 5 of the top plate 2, and receives infrared rays guided by the light guide tube 28.

図4は鍋温度検出装置20の詳細を説明する図である。図4は、図1に示すX−X断面から見た鍋温度検出装置20の断面図を示す。鍋温度検出装置20は、第1の赤外線センサである赤外線センサ21と、図11で後述する第2の赤外線センサである反射型フォトインタラプタ22が設けられている。赤外線センサ21は、熱型検出素子のサーモパイルを例に説明する。赤外線センサ21と反射型フォトインタラプタ22は、赤外線センサ21の出力を増幅する増幅回路と反射型フォトインタラプタ22の出力を増幅する増幅回路を備えた電子回路基板23に配置される。赤外線センサ21と反射型フォトインタラプタ22の各出力は、電子回路基板23の出力端子23a(図5に示す)から出力され、温度換算手段50に出力信号を入力する。 FIG. 4 is a diagram illustrating the details of the pot temperature detecting device 20. FIG. 4 shows a cross-sectional view of the pot temperature detecting device 20 as seen from the XX cross section shown in FIG. The pan temperature detection device 20 is provided with an infrared sensor 21 which is a first infrared sensor and a reflective photointerrupter 22 which is a second infrared sensor described later in FIG. The infrared sensor 21 will be described by taking a thermopile of a thermal detection element as an example. The infrared sensor 21 and the reflective photo interrupter 22 are arranged on an electronic circuit board 23 provided with an amplifier circuit that amplifies the output of the infrared sensor 21 and an amplifier circuit that amplifies the output of the reflective photo interrupter 22. Each output of the infrared sensor 21 and the reflective photo interrupter 22 is output from the output terminal 23a (shown in FIG. 5) of the electronic circuit board 23, and the output signal is input to the temperature conversion means 50.

図11は反射型フォトインタラプタ22を説明する図である。図に示すように反射型フォトインタラプタ22は、赤外線発光手段としての赤外線LED22aと、赤外線受光手段としての赤外線フォトトランジスタ22bで構成している。 FIG. 11 is a diagram illustrating a reflective photo interrupter 22. As shown in the figure, the reflective photo interrupter 22 is composed of an infrared LED 22a as an infrared emitting means and an infrared phototransistor 22b as an infrared receiving means.

赤外線LED22aの発光面上にはプラスチックによるレンズが構成され、細いビームの赤外光をトッププレート2の赤外線透過窓5を介して上方に照射する。また、赤外線フォトトランジスタ22bの受光面上にはプラスチックレンズを装着しており、赤外線LED22aで照射した赤外光が赤外線透過窓5を覆う物体(調理鍋30の底面)にて反射した赤外光を受光し、その受光量に応じた電流を出力する。この反射型フォトインタラプタ22の赤外線フォトトランジスタ22bの出力が温度換算手段50へと入力される。 A lens made of plastic is formed on the light emitting surface of the infrared LED 22a, and infrared light of a thin beam is irradiated upward through the infrared transmission window 5 of the top plate 2. Further, a plastic lens is mounted on the light receiving surface of the infrared phototransistor 22b, and the infrared light emitted by the infrared LED 22a is reflected by an object (bottom surface of the cooking pot 30) covering the infrared transmission window 5. Is received, and a current corresponding to the amount of the received light is output. The output of the infrared phototransistor 22b of the reflective photointerruptor 22 is input to the temperature conversion means 50.

図4と図5を用いて説明する。図5は鍋温度検出装置20の上面図を示す。図5(a)は、電子回路基板23を収納したセンサケース24の上面図、図5(b)は、金属ケース27の上面図、図5(c)は、導光筒28の上面図である。 This will be described with reference to FIGS. 4 and 5. FIG. 5 shows a top view of the pot temperature detecting device 20. 5 (a) is a top view of the sensor case 24 containing the electronic circuit board 23, FIG. 5 (b) is a top view of the metal case 27, and FIG. 5 (c) is a top view of the light guide tube 28. is there.

赤外線センサ21と反射型フォトインタラプタ22を設置した電子回路基板23は、全体を、第2のケースであるプラスチック部材のセンサケース24内に収納される。このセンサケース24の上方には赤外線を透過させるためにケース窓25が開口しており、このケース窓25にはトッププレート2を構成する結晶化ガラスの光学特性に類似した(図10で説明するように1μm以上の長波長側の光学特性がトッププレート2とほぼ同じ。但し、波長1μm以下は透過率が小さく、可視光線をカットする)光学フィルタ26を嵌め込んである。光学フィルタ26の下方に、赤外線センサ21と反射型フォトインタラプタ22が配置された構成である。 The electronic circuit board 23 on which the infrared sensor 21 and the reflective photointerruptor 22 are installed is entirely housed in a sensor case 24 made of a plastic member, which is a second case. A case window 25 is opened above the sensor case 24 to transmit infrared rays, and the case window 25 has similar optical characteristics to the crystallized glass constituting the top plate 2 (described with reference to FIG. 10). As described above, the optical characteristics on the long wavelength side of 1 μm or more are almost the same as those of the top plate 2. However, when the wavelength is 1 μm or less, the transmittance is small and visible rays are cut off), and the optical filter 26 is fitted. The infrared sensor 21 and the reflective photo interrupter 22 are arranged below the optical filter 26.

センサケース24の上面や側面部にはアルミなどの透磁率がほぼ1の金属ケース27で覆っており、先のケース窓25の上方に開口した開口部27aを設けている。 The upper surface and side surfaces of the sensor case 24 are covered with a metal case 27 such as aluminum having a magnetic permeability of substantially 1, and an opening 27a opened above the case window 25 is provided.

金属ケース27の上部には、導光筒28を配置しており、導光筒28は上端開口部28aと下端開口部28bの開口部を設けている。上端開口部28aと下端開口部28bを介して赤外線センサ21の集光レンズ21a(図5に示す)、及び反射型フォトインタラプタ22がトッププレート2を臨むように配置している。導光筒28は、調理鍋30からの赤外線を赤外線センサ21に導き、図11に後述するように反射型フォトインタラプタ22が投光した赤外線が調理鍋30で反射し、反射した赤外線を反射型フォトインタラプタ22に導く光路である。 A light guide tube 28 is arranged on the upper portion of the metal case 27, and the light guide tube 28 is provided with an opening of an upper end opening 28a and an opening of a lower end opening 28b. The condensing lens 21a (shown in FIG. 5) of the infrared sensor 21 and the reflective photointerruptor 22 are arranged so as to face the top plate 2 via the upper end opening 28a and the lower end opening 28b. The light guide tube 28 guides infrared rays from the cooking pot 30 to the infrared sensor 21, and as will be described later in FIG. 11, the infrared rays projected by the reflective photo interrupter 22 are reflected by the cooking pot 30, and the reflected infrared rays are reflected. It is an optical path leading to the photo interrupter 22.

図5(a)より、センサケース24のケース窓25に配置した光学フィルタ26の下方に、赤外線センサ21と反射型フォトインタラプタ22を配置している。赤外線センサ21の集光レンズ21a、及び反射型フォトインタラプタ22は光学フィルタ26を臨む配置としている。図5(b)より、金属ケース27の開口部27aは、下方に配置された光学フィルタ26を臨む。図5(c)より、導光筒28の上端開口部28aは光学フィルタ26を臨む配置としている。即ち、調理鍋30の鍋底をトッププレート2の赤外線透過窓5を介して赤外線センサ21と反射型フォトインタラプタ22が臨む光路を形成している。なお、本実施例は導光筒28の上端開口部28aは、内側加熱コイル3aと外側加熱コイル3cの下方に配置した構成で説明を行うが、これに限らず上端開口部28aは赤外線透過窓5の下方に配置しても良い。 From FIG. 5A, the infrared sensor 21 and the reflective photo interrupter 22 are arranged below the optical filter 26 arranged in the case window 25 of the sensor case 24. The condenser lens 21a of the infrared sensor 21 and the reflective photo interrupter 22 are arranged so as to face the optical filter 26. From FIG. 5B, the opening 27a of the metal case 27 faces the optical filter 26 arranged below. From FIG. 5C, the upper end opening 28a of the light guide tube 28 is arranged so as to face the optical filter 26. That is, an optical path is formed in which the infrared sensor 21 and the reflective photo interrupter 22 face the bottom of the cooking pot 30 through the infrared transmission window 5 of the top plate 2. In this embodiment, the upper end opening 28a of the light guide tube 28 will be described in a configuration in which the upper end opening 28a is arranged below the inner heating coil 3a and the outer heating coil 3c, but the present invention is not limited to this, and the upper end opening 28a is an infrared transmission window. It may be placed below 5.

図6に赤外線センサ21の詳細を示す。図6(a)は赤外線センサ21の斜視図を示す。図6(b)は図6(a)中A−Aで示す線での赤外線センサ21の断面図を示す。図6(c)は集光レンズの光学特性と感熱素子の位置関係を示す。 FIG. 6 shows the details of the infrared sensor 21. FIG. 6A shows a perspective view of the infrared sensor 21. FIG. 6B shows a cross-sectional view of the infrared sensor 21 along the line indicated by AA in FIG. 6A. FIG. 6C shows the optical characteristics of the condenser lens and the positional relationship of the heat sensitive element.

赤外線センサ21は多数の熱電対を直列接続した熱型赤外線検出素子で、ニッケルめっき鋼板などの金属キャン31と金属ステム32からなる、第1のケースである金属ケース33にこれが内蔵されている。 The infrared sensor 21 is a thermal infrared detection element in which a large number of thermocouples are connected in series, and is built in a metal case 33, which is a first case and is composed of a metal can 31 such as a nickel-plated steel plate and a metal stem 32.

シリコン基板34表面に鍋検出用素子35aと温度補償用素子35bを配置している。鍋検出用素子35aと温度補償用素子35bは、ポリシリコン、アルミを順次パターン蒸着しポリシリコン蒸着膜、アルミ蒸着膜で熱電対を多数作成し、これを縦列接続している。ポリシリコン、アルミ接合点(測温接点)のある感熱素子(鍋検出用素子)35aと感熱素子(温度補償用素子)35bとの各々の中央部には、黒体に近い酸化ルビジウム膜あるいはポリイミド膜等の赤外線吸収膜を保護皮膜として形成しており、ポリシリコン及びアルミ蒸着膜の一端は冷接点である。このシリコン基板34を金属ケース33の金属ステム32にボンド等で固定する。 A pot detection element 35a and a temperature compensation element 35b are arranged on the surface of the silicon substrate 34. The pot detection element 35a and the temperature compensation element 35b are formed by sequentially pattern-depositing polysilicon and aluminum to form a large number of thermocouples from the polysilicon-deposited film and the aluminum-deposited film, and these are connected in tandem. A rubidium oxide film or polyimide close to a black body is located at the center of each of the heat-sensitive element (pot detection element) 35a and the heat-sensitive element (temperature compensation element) 35b having a polysilicon and aluminum junction (temperature measuring contact). An infrared absorbing film such as a film is formed as a protective film, and one end of the polysilicon and aluminum vapor deposition film is a cold contact. The silicon substrate 34 is fixed to the metal stem 32 of the metal case 33 with a bond or the like.

金属ステム32には絶縁シールされた複数個の金属ピン36が貫通配置されており、この金属ピン36の先に熱電対の出力がワイヤで接続されている。金属ステム32には筒状の金属キャン31が窒素などの不活性ガス中で被せられ溶着される。 A plurality of metal pins 36 that are insulated and sealed are penetratingly arranged on the metal stem 32, and the output of the thermocouple is connected to the tip of the metal pins 36 by a wire. The metal stem 32 is covered with a tubular metal can 31 in an inert gas such as nitrogen and welded.

この金属キャン31の上面には、小穴の開口部37が開けられている。開口部37には集光レンズ21aが装着されている。 An opening 37 of a small hole is formed on the upper surface of the metal can 31. A condenser lens 21a is attached to the opening 37.

次に図6(c)を用いて、2個の感熱素子(鍋検出用素子35a(第1の感熱素子)と温度補償用素子35b(第2の感熱素子))と集光レンズの光学特性との関係について説明する。 Next, using FIG. 6C, the optical characteristics of the two heat-sensitive elements (pot detection element 35a (first heat-sensitive element) and temperature compensation element 35b (second heat-sensitive element)) and the condenser lens. The relationship with is explained.

集光レンズ21aの光学特性は、鍋の赤外線を効率良く入射し、熱外乱をカットできる、トッププレート2に近い特性であることが望ましい。本実施では、集光レンズの材質は、ホウケイ酸ガラスを使用している。ホウケイ酸ガラスに替えて光学特性が類似している結晶化ガラスや石英ガラスを使用してもよい。 It is desirable that the optical characteristics of the condenser lens 21a are close to those of the top plate 2 so that the infrared rays of the pan can be efficiently incident and the thermal disturbance can be cut. In this implementation, borosilicate glass is used as the material of the condenser lens. Instead of borosilicate glass, crystallized glass or quartz glass having similar optical characteristics may be used.

調理鍋30の温度を検出する鍋検出用素子35aと集光レンズ21aとの位置関係は、鍋検出用素子35aの赤外線受光面の中心35a1と集光レンズ21aの中心を通りレンズ面に垂直な光軸21a1とが略一致する位置関係に有り、該光軸21a1と平行に入射する赤外線35a2は鍋検出用素子35aの赤外線受光面に集光する。 The positional relationship between the pot detection element 35a for detecting the temperature of the cooking pot 30 and the condenser lens 21a is perpendicular to the lens surface through the center 35a1 of the infrared light receiving surface of the pot detection element 35a and the center of the condenser lens 21a. The infrared rays 35a2, which are in a positional relationship that substantially coincides with the optical axis 21a1 and are incident in parallel with the optical axis 21a1, are focused on the infrared receiving surface of the pot detection element 35a.

次に、鍋検出用素子35aを中心とした円周上に設け、鍋検出用素子35aに隣接した位置に温度補償用素子35bを設けたものである。そして温度補償用素子35bと集光レンズ21aとの位置関係は、温度補償用素子35bの赤外線受光面の中心と集光レンズ21aとの中心を結ぶ傾斜した光軸21a2に平行に入射する赤外線35b2が温度補償用素子35bの赤外線受光面で略集光する位置に設けられている。 Next, the pot detection element 35a is provided on the circumference around the center, and the temperature compensation element 35b is provided at a position adjacent to the pot detection element 35a. The positional relationship between the temperature compensating element 35b and the condensing lens 21a is such that the infrared rays 35b2 incident parallel to the inclined optical axis 21a2 connecting the center of the infrared receiving surface of the temperature compensating element 35b and the center of the condensing lens 21a. Is provided at a position where light is substantially collected on the infrared light receiving surface of the temperature compensating element 35b.

以上のことから、鍋検出用素子35aと温度補償用素子35bの両方に集光レンズ21aの発する赤外線は約同量入射される。 From the above, approximately the same amount of infrared rays emitted by the condenser lens 21a is incident on both the pot detection element 35a and the temperature compensation element 35b.

本実施例では、鍋検出用素子35aと温度補償用素子35bを独立した2つのチップをシリコン基板34表面に配置する構成で説明するが、これに限らず1つのチップ上に2素子を配置した構成であっても良い。2素子1チップ化により、各感熱素子の冷接点側の温度条件が同等となり、温度特性による出力変動のレベルを同等に抑えることができる。また、赤外線センサ21の組立工程の簡素化が図れ、センサの低コスト化に寄与する。 In this embodiment, two independent chips of the pot detection element 35a and the temperature compensation element 35b will be described on the surface of the silicon substrate 34, but the present invention is not limited to this, and two elements are arranged on one chip. It may be configured. By using two elements and one chip, the temperature conditions on the cold contact side of each thermal element become the same, and the level of output fluctuation due to the temperature characteristics can be suppressed to the same level. In addition, the assembly process of the infrared sensor 21 can be simplified, which contributes to the cost reduction of the sensor.

図7に検出回路40の概要を示す。赤外線センサ21内は、鍋検出用素子35aの出力(図中(+)、(−)記号)−側と温度補償用素子35bの−側を直列に接続している。鍋検出用素子35aの出力は、+側をオペレーショナルアンプ(以下OPアンプと略称する)41に接続し、温度補償用素子35bの+側をOPアンプ41に接続する。鍋検出用素子35aの+側と温度補償用素子35bの+側の電位差をOPアンプ41で約3000倍に増幅された出力信号が電子回路基板23の出力端子23aから温度換算手段50へと入力される。鍋検出用素子35aの+側の電位は、調理鍋30からの入射エネルギーに比例するものであり、温度補償用素子35bの+側の電位は光学フィルタ26及び集光レンズ21aを透過した入射エネルギーに比例するものである。 FIG. 7 shows an outline of the detection circuit 40. Inside the infrared sensor 21, the output ((+), (-) symbols in the figure) -side of the pot detection element 35a and the-side of the temperature compensation element 35b are connected in series. As for the output of the pan detection element 35a, the + side is connected to the operational amplifier (hereinafter abbreviated as OP amplifier) 41, and the + side of the temperature compensation element 35b is connected to the OP amplifier 41. The output signal obtained by amplifying the potential difference between the + side of the pan detection element 35a and the + side of the temperature compensation element 35b by about 3000 times by the OP amplifier 41 is input from the output terminal 23a of the electronic circuit board 23 to the temperature conversion means 50. Will be done. The potential on the + side of the pot detection element 35a is proportional to the incident energy from the cooking pot 30, and the potential on the + side of the temperature compensation element 35b is the incident energy transmitted through the optical filter 26 and the condenser lens 21a. Is proportional to.

鍋温度検出装置20が加熱コイル3からの輻射熱などにより温められ赤外線センサ21の周囲温度が変化すると金属ケース33が温度変化し、鍋検出用素子35aと温度補償用素子35bの冷接点温度が変化する。鍋検出用素子35aと温度補償用素子35bが隣接しており温度変化が同一となることから、「鍋検出用素子35aの+側の電位」=「温度補償用素子35bの+側の電位」で電位差=0となり、赤外線センサ21の周囲温度変化による出力変動を抑制できる。 When the pot temperature detection device 20 is heated by radiant heat from the heating coil 3 and the ambient temperature of the infrared sensor 21 changes, the temperature of the metal case 33 changes, and the cold contact temperatures of the pot detection element 35a and the temperature compensation element 35b change. To do. Since the pot detection element 35a and the temperature compensation element 35b are adjacent to each other and the temperature changes are the same, "the potential on the + side of the pot detection element 35a" = "the potential on the + side of the temperature compensation element 35b". The potential difference becomes 0, and the output fluctuation due to the change in the ambient temperature of the infrared sensor 21 can be suppressed.

図8に、図6(b)断面図における赤外線センサ21の視野特性を示す。図中の相対感度は、集光レンズの中心軸上(視野角0°)から鍋検知用素子35aに入射した感度を100%としている。温度補償用素子35bは、図7の回路図に示すように鍋検出用素子35aとは感熱素子の+と−出力が反転することから温度補償用素子35bに赤外線が入射するとマイナスの出力値となり視野角+40°付近で約-100%となる。相対感度50%以上の視野特性は、鍋検出用素子35aが約−10°〜+10°、温度補償用素子35bが約+30°〜+50°である。 FIG. 8 shows the visual field characteristics of the infrared sensor 21 in the cross-sectional view of FIG. 6B. As for the relative sensitivity in the figure, 100% is the sensitivity incident on the pan detection element 35a from the central axis of the condenser lens (viewing angle 0 °). As shown in the circuit diagram of FIG. 7, the temperature compensation element 35b has a negative output value when infrared rays are incident on the temperature compensation element 35b because the + and-outputs of the heat sensitive element are reversed from those of the pot detection element 35a. It becomes about -100% near the viewing angle of + 40 °. The visual field characteristics of the relative sensitivity of 50% or more are about −10 ° to + 10 ° for the pot detection element 35a and about + 30 ° to + 50 ° for the temperature compensation element 35b.

この視野特性を図6(b)断面図に、鍋検出用素子35aの検出範囲38、温度補償用素子35bの検出範囲39として示す。鍋検出用素子35aの最大となるピーク感度位置38a(相対感度100%)は、トッププレート2の赤外線透過窓5を通じて調理鍋30の鍋底を検出する位置(光軸21a1(図6(c)))となる。温度補償用素子35bの最大となるピーク感度位置39a(相対感度約−100%)は導光筒28の内壁を検出する位置(光軸21a2(図6(c)))となるように設ければよく、前述した視野角+40°を限定するものではない。 This visual field characteristic is shown in the cross-sectional view of FIG. 6B as a detection range 38 of the pot detection element 35a and a detection range 39 of the temperature compensation element 35b. The maximum peak sensitivity position 38a (relative sensitivity 100%) of the pot detection element 35a is a position where the bottom of the cooking pot 30 is detected through the infrared transmission window 5 of the top plate 2 (optical axis 21a1 (FIG. 6 (c))). ). The maximum peak sensitivity position 39a (relative sensitivity of about -100%) of the temperature compensating element 35b is provided so as to be a position (optical axis 21a2 (FIG. 6C)) for detecting the inner wall of the light guide tube 28. However, the above-mentioned viewing angle + 40 ° is not limited.

次に、調理鍋30底面からの赤外線が赤外線センサ21に入射する光路の特性について説明する。 Next, the characteristics of the optical path in which infrared rays from the bottom surface of the cooking pot 30 are incident on the infrared sensor 21 will be described.

トッププレート2上に置かれた調理鍋30は、誘導加熱により発熱する。この加熱により調理鍋30は温度上昇を始め、温度に比例した赤外線が底面から放射される。この全放射エネルギーEは鍋温度Tの4乗に比例したものである(E=εσT;ステファン・ボルツマンの法則)。 The cooking pot 30 placed on the top plate 2 generates heat by induction heating. By this heating, the temperature of the cooking pot 30 starts to rise, and infrared rays proportional to the temperature are radiated from the bottom surface. This total radiant energy E is proportional to the fourth power of the pot temperature T (E = εσT 4 ; Stefan-Boltzmann's law).

図9にプランクの分布則から算出される、黒体温度の分光放射エネルギーを示す。この分光放射エネルギーを全波長域で積分すれば全放射エネルギーが求まり、これは温度(絶対温度)の4乗に比例する。これが前述のステファン・ボルツマンの法則であり、この係数σがステファン・ボルツマン係数である。分光放射エネルギーのピーク波長はウィーンの変移則から、調理温度100〜300℃で5〜8μmである。 FIG. 9 shows the spectral radiant energy of the blackbody temperature calculated from Planck's distribution law. By integrating this spectral radiant energy in the entire wavelength range, the total radiant energy can be obtained, which is proportional to the fourth power of the temperature (absolute temperature). This is the Stefan-Boltzmann law described above, and this coefficient σ is the Stefan-Boltzmann coefficient. The peak wavelength of the spectral radiant energy is 5 to 8 μm at a cooking temperature of 100 to 300 ° C. according to the Viennese variation law.

誘導加熱された鍋底は、黒体温度の全放射エネルギーEに鍋底の放射率εを乗じた全放射エネルギーを温度に応じて放出する。すなわち、黒体温度の全放射エネルギーEと鍋底温度のそれ(E´=εσT)との比が、放射率εである。 The inducedly heated pot bottom emits the total radiant energy obtained by multiplying the total radiant energy E of the blackbody temperature by the emissivity ε of the pot bottom according to the temperature. That is, the ratio of the total radiant energy E of the blackbody temperature to that of the pot bottom temperature (E'= εσT 4 ) is the emissivity ε.

一方、非磁性体である結晶化ガラス(トッププレート2)の光学特性を図10に実線で示す。図10の実線で示すように、結晶化ガラスは、0.4〜2.9μmの波長の光を80%以上透過し、3〜4.5μmの波長の光を最大50%程度透過し、4.5μmよりも長い波長、及び、0.4μmよりも短い波長の光をほとんど透過しない。ホウケイ酸ガラスもほぼ同等の光学特性を要している。光学フィルタ26の光学特性を図10に一点破線で示す。先に述べた通り、1μm以上の長波長側の光学特性はトッププレート2に近い特性を有し、短波長側の範囲が狭く0.5μmよりも短い波長の光をほとんど透過しない。そのため、光学フィルタ26を透過する事で誘導加熱調理器の調理中の本体内の温度変化(常温〜約75℃)による部品(例えば導光筒28など)から放射される赤外線の影響は略排除できる。 On the other hand, the optical characteristics of the non-magnetic crystallized glass (top plate 2) are shown by solid lines in FIG. As shown by the solid line in FIG. 10, the crystallized glass transmits 80% or more of light having a wavelength of 0.4 to 2.9 μm and transmits light having a wavelength of 3 to 4.5 μm by up to 50%. It hardly transmits light with wavelengths longer than .5 μm and wavelengths shorter than 0.4 μm. Borosilicate glass also requires almost the same optical properties. The optical characteristics of the optical filter 26 are shown by a dashed line in FIG. As described above, the optical characteristics on the long wavelength side of 1 μm or more have characteristics close to those of the top plate 2, and the range on the short wavelength side is narrow so that light having a wavelength shorter than 0.5 μm is hardly transmitted. Therefore, by passing through the optical filter 26, the influence of infrared rays radiated from parts (for example, the light guide tube 28) due to the temperature change (normal temperature to about 75 ° C.) in the main body of the induction heating cooker during cooking is almost eliminated. it can.

誘導加熱された調理鍋30の鍋底より放射される赤外線放射エネルギーは、トッププレート2の赤外線透過窓5、光学フィルタ26、赤外線センサ21の集光レンズ21aの3種類の光学特性の各透過率の積で赤外線センサ21に入射する。このため、調理鍋30から放射される赤外線放射エネルギーの大部分(波長4μm以上、及び0.5μm以下)は赤外線センサ21では受光できない。全波長域で透過率100%(トッププレート2や光学フィルタ26が無い状態)の赤外線放射エネルギーを100%とした場合、赤外線センサ21に受光される赤外線放射エネルギーは、調理鍋30から放射される全赤外線放射エネルギーの1〜2%程度となる。鍋底の赤外線放射エネルギーを効率良く検出するためには、トッププレート2、光学フィルタ26、集光レンズ21aは、同等の波長透過特性を有することが望ましい。 The infrared radiant energy radiated from the bottom of the induction-heated cooking pot 30 has the transmittance of each of the three types of optical characteristics of the infrared transmission window 5 of the top plate 2, the optical filter 26, and the condensing lens 21a of the infrared sensor 21. The product is incident on the infrared sensor 21. Therefore, most of the infrared radiant energy radiated from the cooking pot 30 (wavelength 4 μm or more and 0.5 μm or less) cannot be received by the infrared sensor 21. When the infrared radiant energy with a transmittance of 100% (without the top plate 2 and the optical filter 26) is 100% in the entire wavelength range, the infrared radiant energy received by the infrared sensor 21 is radiated from the cooking pot 30. It is about 1 to 2% of the total infrared radiant energy. In order to efficiently detect the infrared radiant energy at the bottom of the pot, it is desirable that the top plate 2, the optical filter 26, and the condenser lens 21a have the same wavelength transmission characteristics.

また、トッププレート2、光学フィルタ26、集光レンズ21aの何れかに、照明などからの可視光線(波長0.4〜0.8μm)の赤外線センサ21への入射を防止するため、可視光カット機能(0.1μm以下の透過率を0%に近いもの)を持たせる必要が有り、本実施では光学フィルタ26は、1μm以下で透過率が減衰し、0.5μmよりも短い波長の光をほとんど透過しないことから、赤外線センサ21への可視光線(波長域0.4〜0.8μm)の入射を抑制している。 In addition, a visible light cut function (0.1) is used to prevent visible light (wavelength 0.4 to 0.8 μm) from entering the infrared sensor 21 from illumination or the like on any of the top plate 2, the optical filter 26, and the condenser lens 21a. It is necessary to have a transmittance of μm or less (which is close to 0%), and in this implementation, the transmittance of the optical filter 26 is attenuated at 1 μm or less, and light having a wavelength shorter than 0.5 μm is hardly transmitted. Therefore, the incident of visible light (wavelength range 0.4 to 0.8 μm) on the infrared sensor 21 is suppressed.

本実施例では可視光カット機能を光学フィルタ26に付与しているが、トッププレート2の赤外線透過窓5に可視光カット機能を有する場合、光学フィルタ26に可視光カット機能が備わっていなくても良い。 In this embodiment, the visible light cut function is provided to the optical filter 26, but when the infrared transmission window 5 of the top plate 2 has the visible light cut function, even if the optical filter 26 does not have the visible light cut function. good.

また、赤外線センサ21の集光レンズ21aに可視光カット機能を有するシリコンレンズなどを用いた場合、赤外線透過窓5、光学フィルタ26に可視光カット機能が備わっていなくても良い。シリコンレンズの光学特性は、0.8μm以下の波長をカットし,1〜25μmまで透過率50%であり,可視光線の波長領域0.4〜0.8μmをカットする特性を有している。 Further, when a silicon lens or the like having a visible light cutting function is used for the condensing lens 21a of the infrared sensor 21, the infrared transmitting window 5 and the optical filter 26 do not have to have the visible light cutting function. The optical characteristics of the silicon lens are that it cuts wavelengths of 0.8 μm or less, has a transmittance of 50% from 1 to 25 μm, and cuts the wavelength region of visible light of 0.4 to 0.8 μm.

次に、鍋検出用素子35aと温度補償用素子35bとが受光する赤外線放射エネルギーについて以下説明する。 Next, the infrared radiant energy received by the pot detection element 35a and the temperature compensation element 35b will be described below.

鍋検出用素子35aには、調理鍋30からトッププレート2や光学フィルタ26を透過して減衰した赤外線が入射エネルギーQ1として入射し、加熱された鍋などからの熱伝導で温められたトッププレート2から放射された赤外線は光学フィルタ26を透過して減衰した赤外線が外乱として入射エネルギーQ2として入射し、トッププレート2と光学フィルタ26間に配置された部材が誘導加熱コイルなどからの輻射熱で温められ本体内の変動する温度の影響を受けた光学フィルタ26から放射された赤外線が集光レンズ21aを透過して外乱として入射エネルギーQ3として入射し、集光レンズ21aから放射された赤外線が外乱として入射エネルギーQ4として入射し、赤外線センサ21の周囲温度が急変した場合、金属キャン31と金属ステム32からの熱伝導による鍋検出用素子35aの温接点と冷接点側に温度差を生じて発生する温度外乱エネルギーQ5(熱伝達特性のバラツキ)が加わる。従って、鍋検出用素子35aへの全入射エネルギーQ=Q1+Q2+Q3+Q4+Q5となる。 Infrared rays transmitted from the cooking pot 30 through the top plate 2 and the optical filter 26 and attenuated are incident on the pot detection element 35a as incident energy Q1, and the top plate 2 is heated by heat conduction from the heated pot or the like. The infrared rays radiated from the infrared rays are transmitted through the optical filter 26 and attenuated, and the infrared rays are incident as incident energy Q2, and the members arranged between the top plate 2 and the optical filter 26 are heated by radiant heat from the induction heating coil or the like. Infrared rays radiated from the optical filter 26 affected by the fluctuating temperature inside the main body pass through the condenser lens 21a and are incident as incident energy Q3 as disturbance, and infrared rays radiated from the condenser lens 21a are incident as disturbance. When incident as energy Q4 and the ambient temperature of the infrared sensor 21 suddenly changes, the temperature generated due to a temperature difference between the hot and cold contacts of the pot detection element 35a due to heat conduction from the metal can 31 and the metal stem 32. Disturbance energy Q5 (variation in heat transfer characteristics) is added. Therefore, the total incident energy Q = Q1 + Q2 + Q3 + Q4 + Q5 on the pot detection element 35a.

また温度補償用素子35bには、集光レンズ21aのレンズ効果により鍋検出用素子35aとは視野角が偏移することで調理鍋30からの入射エネルギーQ1とトッププレート2からの入射エネルギーQ2は遮光され、トッププレート2と光学フィルタ26間に配置された部材が誘導加熱コイルなどからの輻射熱で温められ本体内の変動する温度の影響を受けた光学フィルタ26から放射された赤外線が集光レンズ21aを透過して外乱として入射エネルギーQ3として入射し、集光レンズ21aから放射された赤外線が外乱として入射エネルギーQ4として入射し、赤外線センサ21の周囲温度が急変した場合、金属キャン31と金属ステム32からの熱伝達による温度補償用素子35bの温接点と冷接点側に温度差を生じて発生する温度外乱エネルギーQ5(熱伝達特性のバラツキ)が加わる。従って、温度補償用素子35bへの全入射エネルギーQ=Q3+Q4+Q5となる。 Further, the temperature compensating element 35b has a viewing angle shifted from that of the pot detecting element 35a due to the lens effect of the condensing lens 21a, so that the incident energy Q1 from the cooking pot 30 and the incident energy Q2 from the top plate 2 are A member that is shielded from light and is arranged between the top plate 2 and the optical filter 26 is heated by radiant heat from an induction heating coil or the like, and infrared rays emitted from the optical filter 26 affected by the fluctuating temperature inside the main body are condensed lenses. When the incident energy Q3 is incident as a disturbance through 21a, the infrared rays radiated from the condenser lens 21a are incident as incident energy Q4 as a disturbance, and the ambient temperature of the infrared sensor 21 suddenly changes, the metal can 31 and the metal stem Temperature disturbance energy Q5 (variation in heat transfer characteristics) generated by causing a temperature difference between the hot contact and the cold contact side of the temperature compensating element 35b due to heat transfer from 32 is added. Therefore, the total incident energy Q = Q3 + Q4 + Q5 on the temperature compensating element 35b.

温度補償用素子35bの視野(検出範囲39)は、集光レンズ21aのレンズ効果により鍋検出用素子35aと異なる。温度補償用素子35bの視野(検出範囲39)の最大となるピーク感度位置39a(相対感度約−100%)は導光筒28の内壁を検出している。しかし、調理中の本体内の温度変化(常温〜約75℃)による導光筒28の影響を受ける温度域(常温〜約75℃)では、導光筒28から放射された赤外線は光学フィルタ26により遮断されるため、温度補償用素子35bの受光するエネルギーとしての影響は大変小さい。 The field of view (detection range 39) of the temperature compensation element 35b is different from that of the pan detection element 35a due to the lens effect of the condenser lens 21a. The peak sensitivity position 39a (relative sensitivity of about -100%), which is the maximum in the field of view (detection range 39) of the temperature compensating element 35b, detects the inner wall of the light guide tube 28. However, in the temperature range (normal temperature to about 75 ° C.) affected by the light guide tube 28 due to the temperature change (normal temperature to about 75 ° C.) in the main body during cooking, the infrared rays emitted from the light guide tube 28 are the optical filter 26. Therefore, the influence of the temperature compensating element 35b as the received energy is very small.

次に、鍋検出用素子35aと温度補償用素子35bの両方に影響を与える前述した外乱について、各入射エネルギーについて入射エネルギー毎にその大きさ等について説明する。 Next, with respect to the above-mentioned disturbance affecting both the pot detection element 35a and the temperature compensation element 35b, the magnitude of each incident energy for each incident energy will be described.

鍋検出用素子35aと温度補償用素子35bとに受光する入射エネルギーQ3は、光学フィルタ26から放射された赤外線が集光レンズ21aを透過して受光されるものである。光学フィルタ26は温度分布ムラの発生を抑えるように導光筒28の鍋温度検出装置20側の冷却風の影響を受け難い位置に設けられている。また、鍋検出用素子35aと温度補償用素子35bの受光する赤外線は光学フィルタ26より放射されたもので、鍋検出用素子35aと温度補償用素子35bの受光する光学フィルタ26の放射する赤外線は、光学フィルタ26の略同じ位置でその大きさも同じ面積である。そのため鍋検出用素子35aの受光する入射エネルギーQ3と温度補償用素子35bの受光する入射エネルギーQ3は、この入射エネルギーQ3の大きさと変化するタイミングは略同じである。 The incident energy Q3 received by the pan detection element 35a and the temperature compensation element 35b is such that infrared rays radiated from the optical filter 26 are transmitted through the condenser lens 21a and received. The optical filter 26 is provided at a position that is not easily affected by the cooling air on the pan temperature detecting device 20 side of the light guide cylinder 28 so as to suppress the occurrence of uneven temperature distribution. Further, the infrared rays received by the pot detection element 35a and the temperature compensation element 35b are emitted from the optical filter 26, and the infrared rays emitted by the optical filter 26 received by the pot detection element 35a and the temperature compensation element 35b are emitted. , The optical filter 26 has substantially the same position and the same size. Therefore, the incident energy Q3 received by the pot detection element 35a and the incident energy Q3 received by the temperature compensating element 35b have substantially the same magnitude and change timing of the incident energy Q3.

また、鍋検出用素子35aと温度補償用素子35bとの受光する入射エネルギーQ4は、鍋検出用素子35aと温度補償用素子35bに入射する集光レンズ21aから放射される赤外線である。鍋検出用素子35aと温度補償用素子35bは前述した様に集光レンズ21aの光軸に対して設置位置を異ならせることで互いに視野を異なるように設置している。但し、集光レンズ21aの放射する赤外線は鍋検出用素子35aと温度補償用素子35bともに同じに受光する。そのため、鍋検出用素子35aと温度補償用素子35bの受光する入射エネルギーQ4の各大きさと各大きさが変化するタイミングは同じである。 The incident energy Q4 received by the pot detection element 35a and the temperature compensation element 35b is infrared rays radiated from the condenser lens 21a incident on the pot detection element 35a and the temperature compensation element 35b. As described above, the pot detection element 35a and the temperature compensation element 35b are installed so as to have different fields of view by different installation positions with respect to the optical axis of the condenser lens 21a. However, the infrared rays emitted by the condenser lens 21a are received in the same manner by both the pot detection element 35a and the temperature compensation element 35b. Therefore, the respective magnitudes of the incident energy Q4 received by the pan detection element 35a and the temperature compensating element 35b and the timing at which each magnitude changes are the same.

鍋検出用素子35aと温度補償用素子35bとに熱伝達される温度外乱エネルギーQ5は、鍋検出用素子35aの温接点と冷接点側に温度差、温度補償用素子35bの温接点と冷接点側に温度差、鍋検出用素子35aと温度補償用素子35bとの温度差によって生じるものである。但し、本実施では1つの集光レンズ21aと1つの金属キャン31と金属ステム32からなる1つの金属ケース33内に鍋検出用素子35aと温度補償用素子35bの両方を収納して、同一のシリコン基板34に配置しているので、鍋検出用素子35aと温度補償用素子35bとに温度差が発生し難い構造としている。そのため、鍋検出用素子35aと温度補償用素子35bとで発生する温度外乱エネルギーQ5は同じ大きさであり、変化するタイミングも同じになる。 The temperature disturbance energy Q5 that is heat-transferred between the pot detection element 35a and the temperature compensation element 35b has a temperature difference between the hot contact and the cold contact side of the pot detection element 35a, and the temperature contact and the cold contact of the temperature compensation element 35b. It is caused by a temperature difference on the side and a temperature difference between the pot detection element 35a and the temperature compensation element 35b. However, in this embodiment, both the pot detection element 35a and the temperature compensation element 35b are housed in one metal case 33 composed of one condenser lens 21a, one metal can 31 and a metal stem 32, and are the same. Since it is arranged on the silicon substrate 34, the structure is such that a temperature difference is unlikely to occur between the pot detection element 35a and the temperature compensation element 35b. Therefore, the temperature disturbance energy Q5 generated by the pot detection element 35a and the temperature compensation element 35b has the same magnitude, and the timing of change is also the same.

以上のことから、鍋検出用素子35aに入力される入射エネルギーQ3と温度補償用素子35bに入力される入射エネルギーQ3、鍋検出用素子35aに入力される入射エネルギーQ4と温度補償用素子35bに入力される入射エネルギーQ4、鍋検出用素子35aに入力される温度外乱エネルギーQ5と温度補償用素子35bに入力される温度外乱エネルギーQ5はそれぞれ等しくなる。 From the above, the incident energy Q3 input to the pot detection element 35a, the incident energy Q3 input to the temperature compensation element 35b, the incident energy Q4 input to the pot detection element 35a, and the temperature compensation element 35b The input incident energy Q4, the temperature disturbance energy Q5 input to the pot detection element 35a, and the temperature disturbance energy Q5 input to the temperature compensation element 35b are equal to each other.

そして、鍋検出用素子35aと温度補償用素子35bは前述した図7に示す回路接続となっているので、鍋検出用素子35aの出力から温度補償用素子35bの出力を差し引いた電位差が増幅された電気信号を出力する構成としている。従って、鍋検出用素子35aと温度補償用素子35が外乱として入力する入射エネルギーQ3と入射エネルギーQ4と温度外乱エネルギーQ5は、その大きさと変化するタイミングが同じなので、鍋検出用素子35aに入力される全入射エネルギーQ=Q1+Q2+Q3+Q4+Q5による鍋検出用素子35aの出力は、温度補償用素子35bに入力される全入射エネルギーQ=Q3+Q4+Q5によって補正され、鍋検出用素子35aの出力から温度補償用素子35bの出力を差し引いた電位差が増幅されて出力される電気信号は、鍋検出用素子35aに入力された入射エネルギーQ=Q1+Q2が増幅された値となる。 Since the pot detection element 35a and the temperature compensation element 35b are connected by the circuit shown in FIG. 7, the potential difference obtained by subtracting the output of the temperature compensation element 35b from the output of the pot detection element 35a is amplified. It is configured to output an electric signal. Therefore, the incident energy Q3, the incident energy Q4, and the temperature disturbance energy Q5 input by the pot detection element 35a and the temperature compensation element 35 as disturbances are input to the pot detection element 35a because their magnitudes and change timings are the same. The output of the pot detection element 35a due to the total incident energy Q = Q1 + Q2 + Q3 + Q4 + Q5 is corrected by the total incident energy Q = Q3 + Q4 + Q5 input to the temperature compensation element 35b, and the output of the pot detection element 35a is corrected by the temperature compensation element 35b. The electric signal output by amplifying the potential difference obtained by subtracting the output is the value obtained by amplifying the incident energy Q = Q1 + Q2 input to the pot detection element 35a.

次に、調理鍋30の鍋底温度の換算方法について説明する。 Next, a method of converting the bottom temperature of the cooking pot 30 will be described.

赤外線センサ21の出力は、入射エネルギーQ1と入射エネルギーQ2の温度に相当した電気信号であることから、調理鍋30の鍋底の温度を求めるためには、入射エネルギーQ2に相当する外乱を補正することにより、更に正確な温度を検出することができる。 Since the output of the infrared sensor 21 is an electric signal corresponding to the temperatures of the incident energy Q1 and the incident energy Q2, in order to obtain the temperature of the bottom of the cooking pot 30, the disturbance corresponding to the incident energy Q2 must be corrected. Therefore, more accurate temperature can be detected.

前記外乱入射エネルギーQ2の補正は、温度センサ14bで計測したトッププレート2の温度に応じた赤外線センサ21の出力信号を補正電圧V2とし、温度換算手段50に登録する。調理鍋30を加熱中に赤外線センサが検出した出力信号V1を温度換算手段50に入力し、温度センサ14bで計測したトッププレート2の温度を温度換算手段50に入力して補正電圧V2を算出し、温度換算手段50において出力信号V1−補正電圧V2の換算処理を行うことで外乱(トッププレート2からの入射エネルギーQ2)を除外することで正確な鍋底の温度を検出することができる。 For the correction of the disturbance incident energy Q2, the output signal of the infrared sensor 21 according to the temperature of the top plate 2 measured by the temperature sensor 14b is set as the correction voltage V2 and registered in the temperature conversion means 50. The output signal V1 detected by the infrared sensor while heating the cooking pot 30 is input to the temperature conversion means 50, and the temperature of the top plate 2 measured by the temperature sensor 14b is input to the temperature conversion means 50 to calculate the correction voltage V2. By performing the conversion process of the output signal V1-correction voltage V2 in the temperature conversion means 50, the disturbance (incident energy Q2 from the top plate 2) can be excluded, and the accurate temperature of the pot bottom can be detected.

また、調理鍋30の温度を検出するためには、同じ温度の調理鍋30でも鍋底の材質や色、傷などの違いによって鍋底から放射される赤外線量が異なるため、赤外線センサ21で検出した赤外線量から調理鍋30の温度を一義的に求めることはできない。調理鍋30の鍋底の温度を求めるためには、鍋底の放射率を得ることで検出した赤外線量を補正して正確な温度を検出することができる。 Further, in order to detect the temperature of the cooking pot 30, the amount of infrared rays emitted from the pot bottom differs depending on the material, color, scratches, etc. of the pot bottom even if the cooking pot 30 has the same temperature. Therefore, the infrared rays detected by the infrared sensor 21 The temperature of the cooking pot 30 cannot be uniquely obtained from the amount. In order to obtain the temperature of the bottom of the cooking pot 30, it is possible to correct the amount of infrared rays detected by obtaining the emissivity of the bottom of the pot and detect the accurate temperature.

放射率は、金属物質の表面から放射される赤外線エネルギ(E=εσT)の放射率εと表面の反射率ρの間に成立するキルヒホフの法則による式(ε+ρ=1)より(但し、透過率α=0とする)、調理鍋30の反射率ρを知ることができれば、鍋30の放射率εを算出できる。ここで、σはステファン・ボルツマン係数、Tは絶対温度である。反射型フォトインタラプタ22でトッププレート2上に置かれた調理鍋30底面の反射率を計測し、温度換算手段50で、その調理鍋30の放射率を算出する。温度換算手段50では、赤外線センサ21からの出力信号V1から温度センサ14bの温度を変換した補正電圧V2を減算した出力信号に放射率を乗算することで、調理鍋30の放射率に応じた正確な鍋温度を検出することができる。 The emissivity is derived from the equation (ε + ρ = 1) according to Kirchhof's law, which holds between the emissivity ε of the infrared energy (E = εσT 4 ) radiated from the surface of the metallic material and the reflectance ρ of the surface (however, transmission). If the reflectance ρ of the cooking pot 30 can be known (the emissivity α = 0), the emissivity ε of the pot 30 can be calculated. Here, σ is the Stefan-Boltzmann coefficient, and T is the absolute temperature. The reflectance of the bottom surface of the cooking pot 30 placed on the top plate 2 is measured by the reflective photo interrupter 22, and the emissivity of the cooking pot 30 is calculated by the temperature conversion means 50. In the temperature conversion means 50, the emissivity is multiplied by the output signal obtained by subtracting the correction voltage V2 obtained by converting the temperature of the temperature sensor 14b from the output signal V1 from the infrared sensor 21, so that the temperature conversion means is accurate according to the emissivity of the cooking pot 30. It is possible to detect the temperature of a hot pot.

ここで、図3の鍋底温度検出手段の構成を示すブロック図を用いて調理鍋30の加熱方法について説明する。上面操作部6aは、火力を設定する火力設定手段52と調理メニューを選択するメニュー設定手段53とを備えている。また、インバータ手段54は、数十kHzの高周波で数百Vの電圧を生成し加熱コイル3に供給するものである。 Here, a method of heating the cooking pot 30 will be described with reference to a block diagram showing the configuration of the pot bottom temperature detecting means of FIG. The upper surface operation unit 6a includes a heating power setting means 52 for setting the heating power and a menu setting means 53 for selecting a cooking menu. Further, the inverter means 54 generates a voltage of several hundred V at a high frequency of several tens of kHz and supplies it to the heating coil 3.

制御手段51は、火力設定手段52より設定された火力で調理鍋30を加熱できるようにインバータ手段54の制御や、メニュー設定手段53で事前に組み込まれた自動メニューの中から選ばれたメニューに基づいてインバータ手段54を制御する。メニュー設定手段53で設定温度を選択して加熱を開始すると、調理鍋30の温度を決められた温度に維持するため温度換算手段50で換算した値の情報に基づいて、加熱コイル3に供給する電力を制御する。また、調理鍋30の異常過熱時には温度換算手段50により検出した調理鍋30の温度情報を基にして、制御手段51から火力低下や停止信号などの制御を行い安全に調理ができる。 The control means 51 controls the inverter means 54 so that the cooking pot 30 can be heated by the heat set by the heat power setting means 52, or selects a menu selected from the automatic menus preliminarily incorporated in the menu setting means 53. The inverter means 54 is controlled based on this. When the set temperature is selected by the menu setting means 53 and heating is started, the temperature of the cooking pot 30 is supplied to the heating coil 3 based on the information of the value converted by the temperature converting means 50 in order to maintain the temperature at the determined temperature. Control power. Further, when the cooking pot 30 is abnormally overheated, the control means 51 controls the heating power decrease, the stop signal, and the like based on the temperature information of the cooking pot 30 detected by the temperature conversion means 50, so that cooking can be performed safely.

以上、本実施例の赤外線センサ21は、1つの集光レンズ21aと1つの金属キャン31と金属ステム32からなる1つの金属ケース33内に2個の感熱素子(鍋検出用素子35a(第1の感熱素子)と温度補償用素子35b(第2の感熱素子)を設け、鍋検出用素子35aの赤外線受光面の中心35a1と集光レンズ21aの中心を通りレンズ面に垂直な光軸21a1とが略一致する位置関係に設け、該光軸21a1と平行に入射する赤外線35a2は鍋検出用素子35aの赤外線受光面に集光させ、鍋検出用素子35aを中心とした円周上かつ鍋検出用素子35aに隣接した位置に温度補償用素子35bを設け、温度補償用素子35bの赤外線受光面と集光レンズ21aとの位置関係は、温度補償用素子35bの赤外線受光面の中心と集光レンズ21aとの中心を結ぶ傾斜した光軸21a2に平行に入射する赤外線35b2が温度補償用素子35bの赤外線受光面で略集光する位置に設けられていることで、下記の効果が得られる。 As described above, the infrared sensor 21 of this embodiment has two heat sensitive elements (pot detection element 35a (first)) in one metal case 33 including one condenser lens 21a, one metal can 31 and a metal stem 32. (Heat sensitive element) and temperature compensation element 35b (second heat sensitive element) are provided, and the center 35a1 of the infrared receiving surface of the pot detection element 35a and the optical axis 21a1 passing through the center of the condensing lens 21a and perpendicular to the lens surface Infrared rays 35a2 incident parallel to the optical axis 21a1 are focused on the infrared receiving surface of the pot detection element 35a, and are located on the circumference of the pot detection element 35a and detect the pot. A temperature compensating element 35b is provided at a position adjacent to the element 35a, and the positional relationship between the infrared light receiving surface of the temperature compensating element 35b and the condensing lens 21a is such that the center of the infrared receiving surface of the temperature compensating element 35b and the condensing lens 21a. The following effects can be obtained by providing the infrared rays 35b2 incident parallel to the inclined optical axis 21a2 connecting the center with the lens 21a at a position where the infrared rays 35b2 are substantially focused on the infrared receiving surface of the temperature compensating element 35b.

鍋検出用素子35aと温度補償用素子35bが同一の1つの集光レンズ21aと1つの金属キャン31と金属ステム32からなる1つ金属ケース33内に収められているので熱伝達特性によるズレは無く精度よく温度検出ができる。 Since the pan detection element 35a and the temperature compensation element 35b are housed in one metal case 33 composed of the same condensing lens 21a, one metal can 31, and a metal stem 32, the deviation due to heat transfer characteristics is caused. The temperature can be detected accurately without any problems.

また、調理鍋30の誘導加熱時は、加熱コイル3からの輻射熱や本体内部の電子部品を冷却した冷却風が吹きつけられることで鍋温度検出装置20が常温〜+20℃の間で過渡的な温度変動を生じるが、鍋検出用素子35aの出力信号を温度補償用素子35bの出力信号でキャンセルすることにより赤外線センサ21の外乱による出力変動を抑制できることとなり、赤外線センサ21の周囲温度が変化した検出条件においても調理鍋30の温度を精度良く検出できる。また、赤外線センサ21を用いれば加熱コイル3からの輻射熱などで温められた光学フィルタ26の入射エネルギーもキャンセルできるため、光学フィルタ26からの熱外乱も抑制できる。光学フィルタ26は、トッププレート2下方の熱外乱の抑制にも寄与するため、外乱となるトッププレート2と光学フィルタ26からの入射エネルギーを抑制できることから調理鍋30の温度を精度良く検出できる。 Further, during the induced heating of the cooking pot 30, the pot temperature detection device 20 is transient between room temperature and + 20 ° C. due to the radiant heat from the heating coil 3 and the cooling air that cools the electronic components inside the main body. Although temperature fluctuation occurs, by canceling the output signal of the pot detection element 35a with the output signal of the temperature compensation element 35b, the output fluctuation due to the disturbance of the infrared sensor 21 can be suppressed, and the ambient temperature of the infrared sensor 21 changes. Even under the detection conditions, the temperature of the cooking pot 30 can be detected accurately. Further, if the infrared sensor 21 is used, the incident energy of the optical filter 26 heated by the radiant heat from the heating coil 3 can be canceled, so that the thermal disturbance from the optical filter 26 can be suppressed. Since the optical filter 26 also contributes to the suppression of thermal disturbance below the top plate 2, the incident energy from the top plate 2 and the optical filter 26, which is a disturbance, can be suppressed, so that the temperature of the cooking pan 30 can be detected accurately.

また、鍋検出用素子35aと温度補償用素子35bの赤外線の受光において、1つの集光レンズ21aを共用して使用することで、鍋検出用素子35aと温度補償用素子35bとには集光レンズ21aによる悪影響となる温度外乱エネルギーQ4は同じエネルギー量として同じ時間に発生するため、温度外乱エネルギーQ4の大小に関係なく精度よく補正する事ができる。また、集光レンズ21aの温度ムラに関しても鍋検出用素子35aと温度補償用素子35bとには同じ温度ムラとして温度外乱エネルギーQ4が同じエネルギー量として同じ時間に発生するため問題なく温度外乱エネルギーQ4として正確に削除できるため、精度よく鍋温度を検出する事ができる。 Further, in receiving infrared light from the pot detection element 35a and the temperature compensation element 35b, by using one condensing lens 21a in common, the pot detection element 35a and the temperature compensation element 35b can condense light. Since the temperature disturbance energy Q4, which is adversely affected by the lens 21a, is generated as the same amount of energy at the same time, it can be accurately corrected regardless of the magnitude of the temperature disturbance energy Q4. Further, regarding the temperature unevenness of the condenser lens 21a, the temperature disturbance energy Q4 is generated in the same time as the same amount of energy as the same temperature unevenness in the pot detection element 35a and the temperature compensation element 35b, so that there is no problem. Because it can be deleted accurately, the pot temperature can be detected accurately.

このため、赤外線センサ21の周囲温度が変化する調理鍋30での長時間調理や連続調理、グリル調理との同時調理条件などであっても、調理鍋30の温度を精度良く検出できる。 Therefore, the temperature of the cooking pot 30 can be accurately detected even under the conditions of long-time cooking, continuous cooking, and simultaneous cooking with the grill cooking in the cooking pot 30 where the ambient temperature of the infrared sensor 21 changes.

しかしながら、鍋検出用素子35aに入力される全入射エネルギーQ=Q1+Q2+Q3+Q4+Q5のうちのQ3+Q4+Q5による出力と、温度補償用素子35bに入力される全入射エネルギーQ=Q3+Q4+Q5による出力は、入射エネルギーが等しい場合であっても、それぞれの感熱素子の感度に差がある場合には同等とならない。この場合、鍋検出用素子35aの出力から温度補償用素子35bの出力を差し引いた電位差が増幅されて出力される電気信号は、鍋検出用素子35aに入力された入射エネルギーQ=Q1+Q2が増幅された値とならず、Q3+Q4+Q5に対する感度の差の分だけ電気信号に影響がある。 However, the output by Q3 + Q4 + Q5 of the total incident energy Q = Q1 + Q2 + Q3 + Q4 + Q5 input to the pan detection element 35a and the output by the total incident energy Q = Q3 + Q4 + Q5 input to the temperature compensation element 35b are when the incident energies are equal. Even if there is a difference in the sensitivity of each heat sensitive element, they are not equivalent. In this case, the potential difference obtained by subtracting the output of the temperature compensating element 35b from the output of the pot detection element 35a is amplified and the output electric signal is amplified by the incident energy Q = Q1 + Q2 input to the pot detection element 35a. The electrical signal is affected by the difference in sensitivity with respect to Q3 + Q4 + Q5.

図12は、本発明の検出回路の一実施例である。 FIG. 12 is an example of the detection circuit of the present invention.

赤外線センサ21の検出回路40を、任意に設定される基準電位70と、基準電位70を第1のバイアス入力とし鍋検出用素子35aの出力を増幅する第1の増幅器61と、基準電位70を第1のバイアス入力として温度補償用素子35bの出力を増幅する第2の増幅器62と、温度補償用素子35bの増幅出力74を第2のバイアス入力として鍋検出用素子35aの増幅出力73を増幅する第3の増幅器63、から構成する。 The detection circuit 40 of the infrared sensor 21 uses an arbitrarily set reference potential 70, a first amplifier 61 that uses the reference potential 70 as a first bias input and amplifies the output of the pot detection element 35a, and a reference potential 70. The second amplifier 62 that amplifies the output of the temperature compensating element 35b as the first bias input, and the amplification output 74 of the temperature compensating element 35b as the second bias input amplifies the amplification output 73 of the pot detection element 35a. It is composed of a third amplifier 63.

基準電位(V0)70は、電源電圧(Vc)76、分圧抵抗(R01)80、分圧抵抗(R02)81によって設定でき、
V0 = Vc×R02/(R01+R02)
と計算できる。分圧抵抗を用いず、基準電位(V0)70を回路グランド77と接続することでも、本発明の検出回路は動作し、検出回路の耐ノイズ性能を高めることができる。
The reference potential (V0) 70 can be set by the power supply voltage (Vc) 76, the voltage dividing resistor (R01) 80, and the voltage dividing resistor (R02) 81.
V0 = Vc × R02 / (R01 + R02)
Can be calculated. Even if the reference potential (V0) 70 is connected to the circuit ground 77 without using the voltage dividing resistor, the detection circuit of the present invention can be operated and the noise resistance performance of the detection circuit can be improved.

第1の増幅器61は、増幅率k1を増幅率設定抵抗(R11)82、増幅率設定抵抗(R12)83によって設定でき、鍋検出用素子35aの増幅出力(V1´)73は、
V1´ = (1+R12/R11)×V1+V0 = k1×V1+V0
とできる。
In the first amplifier 61, the amplification factor k1 can be set by the amplification factor setting resistor (R11) 82 and the amplification factor setting resistor (R12) 83, and the amplification output (V1') 73 of the pot detection element 35a is
V1'= (1 + R12 / R11) x V1 + V0 = k1 x V1 + V0
Can be done.

第2の増幅器62は、増幅率k2を増幅率設定抵抗(R21)84、増幅率設定抵抗(R22)85によって設定でき、鍋検出用素子35bの増幅出力(V2´)74は、
V2´ = (1+R22/R21)×V2+V0 = k2×V2+V0
とできる。
In the second amplifier 62, the amplification factor k2 can be set by the amplification factor setting resistor (R21) 84 and the amplification factor setting resistor (R22) 85, and the amplification output (V2') 74 of the pot detection element 35b can be set.
V2'= (1 + R22 / R21) x V2 + V0 = k2 x V2 + V0
Can be done.

さらに、第3の増幅器63は、増幅率k3を増幅率設定抵抗(R31)86、増幅率設定抵抗(R32)87によって設定でき、検出回路の出力電圧(Vs)75は、
Vs = (1+R32/R31)×(V1´−V2´)+V2´
= k3×(V1´−V2´)+V2´
= k3×(k1×V1+V0−k2×V2−V0)+k2×V2+V0
= k3×{k1×V1−k2×V2+(k2/k3)×V2}+V0
とできる。
Further, in the third amplifier 63, the amplification factor k3 can be set by the amplification factor setting resistor (R31) 86 and the amplification factor setting resistor (R32) 87, and the output voltage (Vs) 75 of the detection circuit can be set.
Vs = (1 + R32 / R31) x (V1'-V2') + V2'
= K3 × (V1'-V2') + V2'
= K3 × (k1 × V1 + V0-k2 × V2-V0) + k2 × V2 + V0
= K3 x {k1 x V1-k2 x V2 + (k2 / k3) x V2} + V0
Can be done.

上記の式で、括弧内の第2項、第3項について、
−k2×V2+(k2/k3)×V2
=−{k2×(1−1/k3)}×V2
=−k2×V2
と変形できる。ここで、感熱素子の出力を増幅する場合、一般的に増幅率k3>>1であることを用いている。
In the above formula, for the second and third terms in parentheses,
-K2 x V2 + (k2 / k3) x V2
=-{K2 × (1-1 / k3)} × V2
= -K2 x V2
Can be transformed. Here, when amplifying the output of the thermal element, it is generally used that the amplification factor is k3 >> 1.

したがって、検出回路の出力電圧(Vs)75は、
Vs = k3×{k1×V1−k2×V2+(k2/k3)×V2}+V0
= k3×(k1×V1−k2×V2)+V0
とできる。
Therefore, the output voltage (Vs) 75 of the detection circuit is
Vs = k3 x {k1 x V1-k2 x V2 + (k2 / k3) x V2} + V0
= K3 × (k1 × V1-k2 × V2) + V0
Can be done.

鍋検出用素子35a、温度補償用素子35bの出力について、増幅率k1と増幅率k2で補正したうえで、増幅率k3で検出回路出力を得ることができる。 The outputs of the pot detection element 35a and the temperature compensation element 35b can be corrected by the amplification factors k1 and the amplification factor k2, and then the detection circuit output can be obtained at the amplification factor k3.

例えば、温度補償用素子35bの感度が、鍋検出用素子35aの感度の0.8倍である場合は、増幅率k2=1.25倍、増幅率k1=1倍と設定することで、感度の差を補正することができる。増幅率k1を1倍としたい場合は、増幅率設定抵抗(R12)83を0Ω(ジャンパ接続)とし、OPアンプ41をバッファとして用いる。 For example, when the sensitivity of the temperature compensation element 35b is 0.8 times the sensitivity of the pot detection element 35a, the sensitivity can be set by setting the amplification factor k2 = 1.25 times and the amplification factor k1 = 1 times. The difference can be corrected. When it is desired to increase the amplification factor k1 to 1, the amplification factor setting resistor (R12) 83 is set to 0Ω (jumper connection), and the OP amplifier 41 is used as a buffer.

上記により、赤外線センサ21の鍋検出用素子35a、温度補償用素子35bの感度の差があっても、本発明の検出回路により補正することができるので、周囲温度が変化する調理鍋30での長時間調理や連続調理、グリル調理との同時調理条件などで、入射エネルギーQ3+Q4+Q5の変化が問題となる場合であっても、調理鍋30の温度をより精度良く検出できる。 As described above, even if there is a difference in sensitivity between the pot detection element 35a and the temperature compensation element 35b of the infrared sensor 21, the difference in sensitivity can be corrected by the detection circuit of the present invention, so that in the cooking pot 30 where the ambient temperature changes. Even when the change of incident energy Q3 + Q4 + Q5 becomes a problem under the conditions of long-time cooking, continuous cooking, simultaneous cooking with grill cooking, etc., the temperature of the cooking pan 30 can be detected more accurately.

図13は、本発明の検出回路の別の実施例である。赤外線センサ21を1つの感熱素子で構成し、赤外線センサ21を2つ逆向きに接続するという方式においても、同様の検出回路を用いることができる。 FIG. 13 is another embodiment of the detection circuit of the present invention. A similar detection circuit can also be used in a method in which the infrared sensor 21 is composed of one heat sensitive element and two infrared sensors 21 are connected in opposite directions.

1…誘導加熱調理器の本体
2…トッププレート
3…加熱コイル
3a…内側加熱コイル、3b…隙間、3c…外側加熱コイル
4…載置部
5…赤外線透過窓
6a、6b、6c…上面操作部
7a、7b、7c…上面表示部
8…グリル庫、8a…ハンドル、8b…グリルドア
9…主電源スイッチ
10…前面操作部
11…排気口
12…コイルベース
13…ギャップスペーサ、13a…支持部材
14…温度センサ、14a…内側温度センサ、14b、14c…外側温度センサ、
20…鍋温度検出装置
21…赤外線センサ、21a…集光レンズ
22…反射型フォトインタラプタ、22a…赤外線LED、
22b…赤外線フォトトランジスタ
23…電子回路基板
24…センサケース
25…ケース窓
26…光学フィルタ
27…金属ケース
28…導光筒
30…調理鍋
31…金属キャン
32…金属ステム
33…金属ケース
34…シリコン基板
35a…鍋検出用素子(第1の感熱素子)
35b…温度補償用素子(第2の感熱素子)
36…金属ピン
37…開口部
38…鍋検出用素子35aの検出範囲、38a…ピーク感度位置
39…温度補償用素子35bの検出範囲、39a…ピーク感度位置
40…検出回路
41…OPアンプ
50…温度換算手段
51…制御手段
52…火力設定手段
53…メニュー設定手段
54…インバータ手段
61…第1の増幅器
62…第2の増幅器
63…第3の増幅器
70…基準電位(V0)(第1のバイアス入力)
71…鍋検出用素子35aの出力電圧(V1)
72…温度補償用素子35bの出力電圧(−V2)
73…鍋検出用素子35aの増幅出力(V1´)
74…温度補償用素子35bの増幅出力(V2´)(第2のバイアス入力)
75…検出回路の出力電圧(Vs)
76…電源電圧(Vc)
77…回路グランド
80…分圧抵抗(R01)
81…分圧抵抗(R02)
82…増幅率設定抵抗(R11)
83…増幅率設定抵抗(R12)
84…増幅率設定抵抗(R21)
85…増幅率設定抵抗(R22)
86…増幅率設定抵抗(R31)
87…増幅率設定抵抗(R32)
1 ... Main body of induction heating cooker 2 ... Top plate 3 ... Heating coil 3a ... Inner heating coil, 3b ... Gap, 3c ... Outer heating coil 4 ... Mounting part 5 ... Infrared transmission window 6a, 6b, 6c ... Top operation part 7a, 7b, 7c ... Top display part 8 ... Grill storage, 8a ... Handle, 8b ... Grill door 9 ... Main power switch 10 ... Front operation part 11 ... Exhaust port 12 ... Coil base 13 ... Gap spacer, 13a ... Support member 14 ... Temperature sensor, 14a ... Inner temperature sensor, 14b, 14c ... Outer temperature sensor,
20 ... Pot temperature detector 21 ... Infrared sensor, 21a ... Condensing lens 22 ... Reflective photo interrupter, 22a ... Infrared LED,
22b ... Infrared phototransistor 23 ... Electronic circuit board 24 ... Sensor case 25 ... Case window 26 ... Optical filter 27 ... Metal case 28 ... Light guide tube 30 ... Cooking pot 31 ... Metal can 32 ... Metal stem 33 ... Metal case 34 ... Silicon Substrate 35a ... Pot detection element (first heat sensitive element)
35b ... Temperature compensation element (second heat sensitive element)
36 ... Metal pin 37 ... Opening 38 ... Detection range of pot detection element 35a, 38a ... Peak sensitivity position 39 ... Detection range of temperature compensation element 35b, 39a ... Peak sensitivity position 40 ... Detection circuit 41 ... OP amplifier 50 ... Temperature conversion means 51 ... Control means 52 ... Thermal power setting means 53 ... Menu setting means 54 ... Inverter means 61 ... First amplifier 62 ... Second amplifier 63 ... Third amplifier 70 ... Reference potential (V0) (First Bias input)
71 ... Output voltage (V1) of the pan detection element 35a
72 ... Output voltage (-V2) of temperature compensating element 35b
73 ... Amplified output (V1') of the pan detection element 35a
74 ... Amplified output (V2') of temperature compensating element 35b (second bias input)
75 ... Output voltage (Vs) of detection circuit
76 ... Power supply voltage (Vc)
77 ... Circuit ground 80 ... Voltage dividing resistor (R01)
81 ... Voltage dividing resistor (R02)
82 ... Amplification rate setting resistor (R11)
83 ... Amplification rate setting resistor (R12)
84 ... Amplification rate setting resistor (R21)
85 ... Amplification rate setting resistor (R22)
86 ... Amplification rate setting resistor (R31)
87 ... Amplification rate setting resistor (R32)

Claims (3)

調理鍋を上面に載置するトッププレートと、
該トッププレートの下方に設けられ前記調理鍋を加熱するために誘導磁界を発生させる加熱コイルと、
該加熱コイルに電力を供給するインバータ手段と、
前記トッププレート越しに前記調理鍋の温度を検出する赤外線センサと、
該赤外線センサの出力を増幅する検出回路と、
該検出回路の出力に応じて前記インバータ手段の出力を制御する制御手段とを備えた誘導加熱調理器において、
前記赤外線センサは、同一の金属ケース内に第1の感熱素子と第2の感熱素子とを備え、
前記検出回路は、任意に設定される基準電位と、該基準電位を第1のバイアス入力とし前記第1の感熱素子の出力を増幅する第1の増幅器と、前記基準電位を第1のバイアス入力として前記第2の感熱素子の出力を増幅する第2の増幅器と、前記第2の感熱素子の増幅出力を第2のバイアス入力として前記第1の感熱素子の増幅出力を増幅する第3の増幅器とを備えたことを特徴とする誘導加熱調理器。
A top plate on which the cooking pot is placed on the top and
A heating coil provided below the top plate to generate an induced magnetic field to heat the cooking pot,
Inverter means for supplying electric power to the heating coil and
An infrared sensor that detects the temperature of the cooking pot through the top plate,
A detection circuit that amplifies the output of the infrared sensor,
In an induction heating cooker provided with a control means for controlling the output of the inverter means according to the output of the detection circuit.
The infrared sensor includes a first heat sensitive element and a second heat sensitive element in the same metal case.
The detection circuit has an arbitrarily set reference potential, a first amplifier that uses the reference potential as a first bias input to amplify the output of the first heat-sensitive element, and a first bias input that uses the reference potential as a first bias input. A second amplifier that amplifies the output of the second heat-sensitive element, and a third amplifier that amplifies the amplified output of the first heat-sensitive element by using the amplified output of the second heat-sensitive element as a second bias input. An induction heating cooker characterized by being equipped with.
請求項1に記載の誘導加熱調理器において、
前記第1の感熱素子と前記第2の感熱素子とは、1つのチップ上に配置されていることを特徴とする誘導加熱調理器。
In the induction heating cooker according to claim 1,
An induction heating cooker characterized in that the first heat-sensitive element and the second heat-sensitive element are arranged on one chip.
請求項1または2に記載の誘導加熱調理器において、
前記トッププレートと第2のケースとの間に設けられており、前記トッププレートに設けられた窓を通過した赤外線が通過する筒体を備え、
前記第1の感熱素子の視野範囲の相対感度が最大となるピーク感度位置は、前記調理鍋を検出する位置であり、
前記第2の感熱素子の視野範囲の相対感度が最大となるピーク感度位置は、前記筒体の内壁を検出する位置であることを特徴とする誘導加熱調理器。
In the induction heating cooker according to claim 1 or 2.
It is provided between the top plate and the second case, and includes a cylinder through which infrared rays passing through a window provided on the top plate pass.
The peak sensitivity position where the relative sensitivity in the visual field range of the first heat sensitive element is maximized is the position where the cooking pot is detected.
An induction heating cooker characterized in that the peak sensitivity position where the relative sensitivity in the visual field range of the second heat sensitive element is maximized is a position where the inner wall of the cylinder is detected.
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