JPH0627166A - Microwave energy detector - Google Patents

Microwave energy detector

Info

Publication number
JPH0627166A
JPH0627166A JP4202037A JP20203792A JPH0627166A JP H0627166 A JPH0627166 A JP H0627166A JP 4202037 A JP4202037 A JP 4202037A JP 20203792 A JP20203792 A JP 20203792A JP H0627166 A JPH0627166 A JP H0627166A
Authority
JP
Japan
Prior art keywords
microwave
sensor
radio wave
wave absorber
microwave energy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP4202037A
Other languages
Japanese (ja)
Other versions
JPH0827314B2 (en
Inventor
Masahiro Hirama
昌弘 平間
Masami Koshimura
正己 越村
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Materials Corp
Original Assignee
Mitsubishi Materials Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Materials Corp filed Critical Mitsubishi Materials Corp
Priority to JP4202037A priority Critical patent/JPH0827314B2/en
Priority to US07/989,173 priority patent/US5378875A/en
Priority to CA002085527A priority patent/CA2085527C/en
Priority to NL9202189A priority patent/NL193485C/en
Priority to GB9226657A priority patent/GB2263173B/en
Priority to DE4243597A priority patent/DE4243597C2/en
Priority to FR9215873A priority patent/FR2685772A1/en
Priority to KR1019920025659A priority patent/KR970002015B1/en
Publication of JPH0627166A publication Critical patent/JPH0627166A/en
Publication of JPH0827314B2 publication Critical patent/JPH0827314B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Thermistors And Varistors (AREA)

Abstract

PURPOSE:To detect a microwave energy accurately without reducing heat dissipation by previously inputting a heat dissipation constant and a heat time constant to a computer and then calculating the value of a microwave energy value as a time function according to a specific equation. CONSTITUTION:The memory which Is provided at an electronic oven 13 stores an expression E=C.dtheta/dt+delta.theta (where, E is the microwave energy absorbed by a radio wave absorber 12, theta is the temperature increase value detected by a thermistor 11, C is the thermal capacity of a microwave sensor 10, and deltais the heat dissipation constant of the sensor 10) and a heat time constant tau. The detection output of the sensor 10 is connected to a computer 30 and the temperature increase value theta accompanied by the heat release of the absorber 12 is input to the device 30 as the electric signal of the element 11. The device 30 substitutes the temperature increase value theta in the stored equation and accurately calculates the amount of the microwave energy to which an object to be heated considering the heat dissipation of the sensor 10 receives.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は電子レンジのようなマイ
クロ波加熱装置において被加熱体の加熱状況又は仕上り
状況を検出するに適したマイクロ波センサを用いたマイ
クロ波エネルギ検出装置に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave energy detecting device using a microwave sensor suitable for detecting a heating condition or a finishing condition of an object to be heated in a microwave heating device such as a microwave oven. .

【0002】[0002]

【従来の技術】電子レンジにはマイクロ波加熱による冷
凍食品の解凍機能、冷えた食品の温め機能等各種機能が
装備されている。電子レンジではこの種の食品の加熱状
況又は仕上り状況をセンサにより検出してマイクロ波を
発生するマグネトロンの出力を自動的に制御している。
従来、食品の冷凍状態から解凍状態までの温度変化を追
跡し、解凍サイクルの終りを検出する電子レンジが開示
されている(特開昭64−50385)。この電子レン
ジはマイクロ波を吸収して発熱する検出器とその温度を
測定する素子とその温度から電子レンジの作動を制御す
る計算及び制御装置を備える。検出器は電子レンジ内の
処理すべき製品の近傍に配置され、計算及び制御装置は
時間の関数としての検出器の温度上昇を表わす曲線を求
め、この曲線の二次導関数の値を計算することにより製
品の解凍サイクルの終りを決定し、また二次導関数の値
が所定値よりも小さくなる解凍サイクルの終了時に電子
レンジの作動を制御する。
2. Description of the Related Art Microwave ovens are equipped with various functions such as a function for thawing frozen food by microwave heating and a function for warming cold food. The microwave oven automatically controls the output of the magnetron that generates microwaves by detecting the heating status or finishing status of this type of food with a sensor.
Conventionally, there has been disclosed a microwave oven which detects the end of the thawing cycle by tracking the temperature change from the frozen state to the thawed state of food (Japanese Patent Laid-Open No. 64-50385). This microwave oven includes a detector that absorbs microwaves and generates heat, an element that measures the temperature thereof, and a calculation and control device that controls the operation of the microwave oven from the temperature. The detector is placed in the microwave oven in the vicinity of the product to be treated and the calculation and control device determines a curve representing the temperature rise of the detector as a function of time and calculates the value of the second derivative of this curve. It determines the end of the thawing cycle of the product and controls the operation of the microwave oven at the end of the thawing cycle where the value of the second derivative is less than a predetermined value.

【0003】また、複数の順次の解凍作業において各解
凍作業の終了を一定の感度で検出できる検出器を備えた
別の電子レンジが開示されている(特開昭64−503
84)。この電子レンジもマイクロ波検出器と温度測定
素子と計算及び制御装置とを備える。この電子レンジで
は、検出器がマイクロ波を透過するが、マイクロ波の吸
収により発熱した検出器の外部への熱放散を防止する熱
絶縁体を含んでいる。この熱絶縁体により外部との熱交
換が減少して温度上昇が増加するので、検出器は各解凍
作業を感度を低下させることなく検出できる。またこの
検出器は外部に対する熱交換面積が大きくかつその厚さ
が薄く形成される。このため検出器は外部との熱交換が
促進され、各解凍作業後に初期特性を急速に回復する熱
的ラグの小さいものになる。
Further, another microwave oven provided with a detector capable of detecting the end of each thawing operation with a constant sensitivity in a plurality of sequential thawing operations is disclosed (Japanese Patent Laid-Open No. 64-503).
84). This microwave oven also comprises a microwave detector, a temperature measuring element and a calculation and control device. In this microwave oven, the detector transmits microwaves, but includes a heat insulator that prevents heat generated by absorption of microwaves from being dissipated to the outside of the detector. The heat insulator reduces the heat exchange with the outside and increases the temperature rise, so that the detector can detect each thawing operation without reducing the sensitivity. Further, this detector has a large heat exchange area for the outside and a thin thickness. This facilitates heat exchange with the outside of the detector, resulting in a small thermal lag that rapidly restores its initial properties after each thawing operation.

【0004】[0004]

【発明が解決しようとする課題】特開昭64−5038
5号公報に示される電子レンジでは、製品が氷の状態か
ら水の状態に移行すると、製品は徐々により多くのマイ
クロ波エネルギを吸収して徐々に加熱され、検出器に吸
収されるエネルギは徐々に減少する。ここで、時間の関
数として検出器の温度上昇を示す曲線の勾配(一次導関
数)を測定した場合に、この勾配がやや減少し二次導関
数の絶対値が所定値よりも大きくなったとき、電子レン
ジ内の製品は解凍し始める。またこの勾配が緩やかにな
り、二次導関数の絶対値が所定値よりも小さくなったと
き、製品は解凍を終了する。上記電子レンジはこの二次
導関数の変化から解凍状態を決定している。しかし、こ
の解凍状態の決定方法によれば二次導関数の変化をもた
らすのは、検出器に吸収されるマイクロ波エネルギの変
化のみでなくてはならない。
Problems to be Solved by the Invention JP-A-64-5038
In the microwave oven disclosed in Japanese Patent Publication No. 5, when the product shifts from the ice state to the water state, the product gradually absorbs more microwave energy and is gradually heated, and the energy absorbed by the detector gradually. Decrease to. Here, when measuring the slope (first derivative) of the curve showing the temperature rise of the detector as a function of time, when this slope decreases slightly and the absolute value of the second derivative becomes larger than a predetermined value. , The product in the microwave begins to thaw. When the gradient becomes gentle and the absolute value of the second derivative becomes smaller than the predetermined value, the product finishes thawing. The microwave oven determines the defrosting state from the change in the second derivative. However, according to this method of determining the defrosted state, it is only the change in the microwave energy absorbed by the detector that causes the change in the second derivative.

【0005】一方、一般に熱容量Cを持つ被加熱物質、
例えばマイクロ波センサがマイクロ波エネルギEを受け
たときのt時間後の温度上昇値θは外部への熱放散が全
くない、完全な断熱状態において、次の式(2)で表わ
される。この関係は図10に示される。 θ = E・t/C (2) しかしながら、実際の被加熱物質では、マイクロ波エネ
ルギを受けたときに外部への熱放散を無視することがで
きない。この場合、被加熱物質が熱放散定数δを持つ場
合、微小時間dtにこの物質が受取るエネルギE・dt
は次の式(3)で表わされる。 E・dt = C・dθ + δ・θ・dt (3) ただし、dθは微小時間に上昇した温度、C・dθは微
小時間に物質に蓄えられた熱エネルギ、δ・θ・dtは
微小時間に周囲に放散した熱エネルギである。上記式
(3)から温度上昇値θはエネルギEが一定のとき次の
式(4)で表わされる。この関係は図11に示される。 θ = (E/δ)・{1−exp(−t/τ)} (4) ただし、τは熱時定数であって、C=τ・δの関係があ
る。図10及び図11から明らかなように、温度上昇値
θが大きくなるに従って、式(1)と式(2)との差が
増大する。
On the other hand, a substance to be heated, which generally has a heat capacity C,
For example, the temperature rise value θ after t hours when the microwave sensor receives the microwave energy E is expressed by the following equation (2) in a completely adiabatic state where there is no heat dissipation to the outside. This relationship is shown in FIG. θ = E · t / C (2) However, in the actual substance to be heated, the heat dissipation to the outside cannot be ignored when the microwave energy is received. In this case, if the substance to be heated has a heat dissipation constant δ, the energy E · dt received by this substance in a minute time dt
Is expressed by the following equation (3). E · dt = C · dθ + δ · θ · dt (3) where dθ is the temperature increased in a minute time, C · dθ is the thermal energy stored in the substance in a minute time, and δ · θ · dt is a minute time. Is the heat energy that is dissipated to the surroundings. From the equation (3), the temperature rise value θ is represented by the following equation (4) when the energy E is constant. This relationship is shown in FIG. θ = (E / δ) · {1-exp (−t / τ)} (4) However, τ is a thermal time constant and has a relationship of C = τ · δ. As is clear from FIGS. 10 and 11, as the temperature rise value θ increases, the difference between the equations (1) and (2) increases.

【0006】さて、上記式(4)から特開昭64−50
385号公報に述べられた一次導関数(dθ/dt)及
び二次導関数(d2θ/dt2)を求めると、次の式
(5)及び式(6)がそれぞれ得られる。これらの関係
は図12及び図13に示される。 dθ/dt =(E/δ/τ)・exp(−t/τ) (5) d2θ/dt2=(−E/δ/τ2)・exp(−t/τ) (6) 図13及び式(6)から二次導関数(d2θ/dt2)は
時間tが零から無限大(0〜∞)の範囲において、(−
E/δ/τ2)から0へと変化することを示しており、
熱放散を考慮すると時間に対しエネルギが変化しない場
合でも二次導関数の変化がもたらされる。このことは特
開昭64−50385号公報の電子レンジの解凍状態の
決定方法が温度上昇値θが大きくなった状態では、正確
でないことを示唆している。即ち、上記電子レンジでは
検出器に吸収されるマイクロ波エネルギの変化のみで二
次導関数の変化をみて、この二次導関数の変化から解凍
状態を決定しているが、実際にはマイクロ波センサの熱
放散を考慮する必要がある。
From the above formula (4), Japanese Patent Laid-Open No. 64-50
When the first derivative (dθ / dt) and the second derivative (d 2 θ / dt 2 ) described in Japanese Patent No. 385 are obtained, the following equations (5) and (6) are obtained. These relationships are shown in FIGS. dθ / dt = (E / δ / τ) · exp (−t / τ) (5) d 2 θ / dt 2 = (− E / δ / τ 2 ) · exp (−t / τ) (6) Figure 13 and equation (6), the second derivative (d 2 θ / dt 2 ) is (−) in the range of time t from zero to infinity (0 to ∞).
E / δ / τ 2 ) changes to 0,
Considering heat dissipation results in a change in the second derivative even if the energy does not change over time. This suggests that the method for determining the defrosting state of the microwave oven disclosed in JP-A-64-50385 is not accurate when the temperature rise value θ is large. That is, in the above microwave oven, the change of the second derivative is observed only by the change of the microwave energy absorbed by the detector, and the defrosting state is determined from the change of the second derivative. It is necessary to consider the heat dissipation of the sensor.

【0007】また、特開昭64−50384号公報に示
される電子レンジでは、上述したように熱絶縁体を用
い、かつ熱放散し易い構造を採用している。熱絶縁体
はマイクロ波が照射されている間は熱放散を減少させ、
熱放散し易い構造はマイクロ波が照射されない間は熱
放散を大きくし速やかに初期状態に復帰させ、かつ繰返
し加熱する場合の熱の累積による熱破壊の防止をはかっ
ている。しかし、上記とは相反するものであり、そ
れぞれ十分に満足することは不可能である。
Further, the microwave oven disclosed in Japanese Patent Laid-Open No. 64-50384 uses a heat insulator as described above and employs a structure that easily dissipates heat. Thermal insulators reduce heat dissipation during microwave irradiation,
The structure that easily dissipates heat is intended to increase the heat dissipation while not being irradiated with microwaves to quickly return to the initial state, and prevent thermal destruction due to accumulated heat when repeatedly heated. However, it is contrary to the above, and it is impossible to satisfy each of them sufficiently.

【0008】本発明の目的は、マイクロ波センサの熱放
散を必ずしも減少させる必要がなく、この熱放散を考慮
して、正確にマイクロ波エネルギを検出できる装置を提
供することにある。
An object of the present invention is to provide a device capable of accurately detecting microwave energy in consideration of this heat dissipation without necessarily reducing the heat dissipation of the microwave sensor.

【0009】[0009]

【課題を解決するための手段】図1に示すように、本発
明は、マイクロ波を吸収して発熱する電波吸収体12と
この吸収体12の温度を検出するサーミスタ素子11と
を有するマイクロ波センサ10と、このマイクロ波セン
サ10の検出出力に基づいてマイクロ波エネルギの値を
計算する計算装置30とを備えたマイクロ波エネルギ検
出装置である。その特徴ある構成は、前記計算装置30
が下記式(1)によりマイクロ波エネルギの値を時間の
関数として計算することにある。 E = C・dθ/dt + δ・θ (1) ただし、Eは前記電波吸収体が吸収したマイクロ波エネ
ルギ、θは前記サーミスタ素子が検出する温度上昇値、
Cは前記マイクロ波センサの熱容量、δは前記マイクロ
波センサの熱放散定数である。上記式(1)は前述した
式(3)の両辺をdtで除すことにより求められる。こ
の式(1)から時間に対するマイクロ波エネルギEが、
センサの熱容量C、熱放散定数δ、時間に対する温度上
昇値θ及びその変化率dθ/dtから求められる。な
お、マイクロ波エネルギEの値を、マイクロ波センサの
受波面積で除算すれば、単位面積当りの照射エネルギと
して表わすこともできる。
As shown in FIG. 1, the present invention provides a microwave having a radio wave absorber 12 that absorbs microwaves to generate heat and a thermistor element 11 that detects the temperature of the absorber 12. The microwave energy detection device includes a sensor 10 and a calculation device 30 that calculates a value of microwave energy based on a detection output of the microwave sensor 10. The characteristic configuration is that of the computing device 30.
Is to calculate the value of microwave energy as a function of time by the following equation (1). E = C · dθ / dt + δ · θ (1) where E is the microwave energy absorbed by the radio wave absorber, θ is the temperature rise value detected by the thermistor element,
C is the heat capacity of the microwave sensor, and δ is the heat dissipation constant of the microwave sensor. The above equation (1) is obtained by dividing both sides of the above equation (3) by dt. From this equation (1), the microwave energy E with respect to time is
It is determined from the heat capacity C of the sensor, the heat dissipation constant δ, the temperature rise value θ with respect to time, and its rate of change dθ / dt. If the value of the microwave energy E is divided by the wave receiving area of the microwave sensor, it can be expressed as irradiation energy per unit area.

【0010】[0010]

【作用】計算装置30には予め式(1)の関係とマイク
ロ波センサ10に固有の熱容量C及び熱放散定数δの各
値を記憶させておく。マイクロ波センサ10にマイクロ
波が到来すると、電波吸収体12がこれを吸収して発熱
する。マイクロ波エネルギ量に相応してこの発熱量は変
化する。この発熱に伴う温度上昇値θが計算装置30に
入力する。計算装置30はこのθが入力すると前記式
(1)を計算し、マイクロ波センサ10の熱放散を考慮
した被加熱物が受けるマイクロ波エネルギ量を正確に求
める。
In the calculation device 30, the relationship of the equation (1) and the respective values of the heat capacity C and the heat dissipation constant δ peculiar to the microwave sensor 10 are stored in advance. When microwaves arrive at the microwave sensor 10, the radio wave absorber 12 absorbs the microwaves and generates heat. This amount of heat generation changes according to the amount of microwave energy. The temperature rise value θ associated with this heat generation is input to the calculation device 30. The calculator 30 calculates the above equation (1) when this θ is input, and accurately obtains the microwave energy amount received by the object to be heated in consideration of the heat dissipation of the microwave sensor 10.

【0011】[0011]

【実施例】次に、本発明の実施例を図面に基づいて詳し
く説明する。図1及び図2に示すように、電子レンジ1
3の前面には扉14が開閉可能に設けられる。電子レン
ジ13の加熱室17の天井部にはマイクロ波センサ10
が設けられる。このマイクロ波センサ10はサーミスタ
素子11の感温部11aが平板状の電波吸収体12に接
着される。マイクロ波センサ10は天井部のフレーム1
5に形成されたスリット16内に加熱室17に臨んで固
定される。センサ10のリード11cはマイクロ波源で
あるマグネトロン18からのマイクロ波を受けない位置
に設けられる。
Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, a microwave oven 1
A door 14 is provided on the front surface of 3 so as to be openable and closable. The microwave sensor 10 is installed on the ceiling of the heating chamber 17 of the microwave oven 13.
Is provided. In the microwave sensor 10, the temperature sensitive portion 11a of the thermistor element 11 is adhered to the plate-shaped radio wave absorber 12. The microwave sensor 10 is the frame 1 of the ceiling
It is fixed so as to face the heating chamber 17 in the slit 16 formed in 5. The lead 11c of the sensor 10 is provided at a position where it does not receive the microwave from the magnetron 18, which is a microwave source.

【0012】サーミスタ素子11は直径1.35mmで
厚さ1.45mmのメルフ(MetalElectrode Face)型
素子であって、Mn,Co,Niを主成分とする金属酸
化物の焼結体からなる感温部11aを有し、その両端の
端子電極11bにリード11cをはんだ付けして作られ
る。このサーミスタ素子11の25℃における抵抗値は
100kΩであって、B定数は3965Kである。電波
吸収体12はSiCの焼結体であって、直径12mmで
厚さ1mmのサイズに作られる。この電波吸収体12の
一方の面12aはマイクロ波吸収面であり、その他方の
面12bの中央に上記リード付きサーミスタ素子11の
感温部11aがエポキシ樹脂10aにより接着される。
サーミスタ素子11、電波吸収体12及びエポキシ樹脂
10aを含むマイクロ波センサ10の熱放散定数δは6
mW/℃であり、その熱時定数τは40秒である。
The thermistor element 11 is a Melf (Metal Electrode Face) type element having a diameter of 1.35 mm and a thickness of 1.45 mm, and is a temperature-sensitive element made of a sintered body of a metal oxide containing Mn, Co and Ni as main components. It has a portion 11a, and is made by soldering leads 11c to the terminal electrodes 11b at both ends thereof. The resistance value of this thermistor element 11 at 25 ° C. is 100 kΩ, and the B constant is 3965K. The radio wave absorber 12 is a sintered body of SiC and has a diameter of 12 mm and a thickness of 1 mm. One surface 12a of the radio wave absorber 12 is a microwave absorbing surface, and the temperature sensitive portion 11a of the thermistor element with lead 11 is adhered to the center of the other surface 12b with an epoxy resin 10a.
The heat dissipation constant δ of the microwave sensor 10 including the thermistor element 11, the radio wave absorber 12 and the epoxy resin 10a is 6
mW / ° C., and its thermal time constant τ is 40 seconds.

【0013】加熱室17の奥部には2450MHzのマ
イクロ波を発生するマグネトロン18が、またその背後
にはブロアファン19及びファンモータ20がそれぞれ
設けられる。加熱室17の底部には容器21を載せてモ
ータ23により回転するターンテーブル22が設けられ
る。ファンモータ20の近傍には吸気口24が、また加
熱室17の天井部には排気口26がそれぞれ設けられ
る。電子レンジ13にはCPU及びメモリを含むコント
ローラ30が設けられる。このメモリには前述した式
(1)の関係と前述した熱放散定数δ及び熱時定数τの
各値が記憶される。マイクロ波センサ10の検出出力は
コントローラ30に接続され、電波吸収体12の発熱に
伴う温度上昇値θがサーミスタ素子11の電気信号とし
てコントローラ30に入力する。またコントローラ30
の制御出力はマグネトロン18、モータ20及び23に
それぞれ接続される。
A magnetron 18 for generating a microwave of 2450 MHz is provided at the back of the heating chamber 17, and a blower fan 19 and a fan motor 20 are provided behind it. At the bottom of the heating chamber 17, there is provided a turntable 22 on which a container 21 is placed and which is rotated by a motor 23. An intake port 24 is provided near the fan motor 20, and an exhaust port 26 is provided at the ceiling of the heating chamber 17. The microwave oven 13 is provided with a controller 30 including a CPU and a memory. This memory stores the relationship of the above-mentioned equation (1) and the above-mentioned respective values of the heat dissipation constant δ and the thermal time constant τ. The detection output of the microwave sensor 10 is connected to the controller 30, and the temperature rise value θ accompanying the heat generation of the radio wave absorber 12 is input to the controller 30 as an electric signal of the thermistor element 11. Also the controller 30
The control output of is connected to the magnetron 18 and the motors 20 and 23, respectively.

【0014】次に、このように構成された電子レンジを
用いてマイクロ波エネルギ検出試験を行った。マイクロ
波出力は200W相当のレンジ弱の状態に設定した。ま
た加熱室17に照射されたマイクロ波エネルギ量を調べ
るためにコントローラ30に記録装置27を接続した。 <試験A>最初にターンテーブル22上に何も載せない
状態でコントローラ30によりマグネトロン18からマ
イクロ波を加熱室17に照射した。照射時間の経過に従
ってコントローラ30が計算したエネルギ量を記録装置
27により記録した。その結果を図3に示す。この場
合、ターンテーブル22上に被加熱物がないため、マイ
クロ波センサ10に入射されるエネルギ量は時間に対し
てほぼ一定に推移した。 <試験B>次にターンテーブル22上の容器21に氷1
00gを入れ、同様にマイクロ波を加熱室17に照射し
た。この場合、マイクロ波センサ10に入射されるエネ
ルギは氷が融けるに従って低下するものと予想された。
試験Aと同様にコントローラ30が計算したエネルギ量
を記録した結果、図4に示すようにエネルギ量は200
秒前後で低下しており、その予想が妥当なものであるこ
とが認められた。試験A及びBの結果からこの実施例の
マイクロ波センサ10は入射されたエネルギを的確に捉
えていることが判明した。なお、図4のPに示されるエ
ネルギ量が極小値となる時点を解凍終了としておき、コ
ントローラ30がこの状態を求めたところでマグネトロ
ン18のマイクロ波出力を制御すれば、解凍終了検出器
となる。
Next, a microwave energy detection test was conducted using the microwave oven configured as described above. The microwave output was set to a state in which the range corresponding to 200 W was weak. In addition, a recording device 27 was connected to the controller 30 in order to check the amount of microwave energy applied to the heating chamber 17. <Test A> First, the heating chamber 17 was irradiated with microwaves from the magnetron 18 by the controller 30 with nothing placed on the turntable 22. The energy amount calculated by the controller 30 according to the elapsed irradiation time was recorded by the recording device 27. The result is shown in FIG. In this case, since there is no object to be heated on the turntable 22, the amount of energy incident on the microwave sensor 10 remained substantially constant with time. <Test B> Next, add ice 1 to the container 21 on the turntable 22.
The heating chamber 17 was irradiated with microwaves in the same manner. In this case, it was expected that the energy incident on the microwave sensor 10 would decrease as the ice melted.
As a result of recording the energy amount calculated by the controller 30 as in the test A, the energy amount is 200 as shown in FIG.
It decreased around the second, and it was confirmed that the prediction was valid. From the results of the tests A and B, it was found that the microwave sensor 10 of this example accurately captured the incident energy. If the defrosting end is set at the time when the energy amount shown by P in FIG. 4 reaches the minimum value, and the controller 30 controls the microwave output of the magnetron 18 when this state is obtained, the defrosting completion detector is obtained.

【0015】なお、本発明のマイクロ波センサは上記例
で示した以外に、本出願人がこれまでそれぞれ特許出願
した図5〜図9に示されるものを用いることができる。
図5に示されるマイクロ波センサ10は、サーミスタ素
子11の感温部11aが電波吸収体粉末を充填材として
含む有機物質32又は無機物質により被覆される。この
センサに関して特願平3−244449号により出願し
た。図6に示されるマイクロ波センサ10は、サーミス
タ素子11に近接してこのサーミスタ素子11をそのリ
ード11cを含めて被包する金属被包体33と、この金
属被包体33の表面に層状に形成された電波吸収体12
とを備える。サーミスタ素子11は充填材36により金
属被包体33内で固定されることが好ましい。このセン
サに関して特願平4−100348号により出願した。
As the microwave sensor of the present invention, in addition to the examples shown in the above examples, the ones shown in FIGS. 5 to 9 which the present applicant has applied for patents can be used.
In the microwave sensor 10 shown in FIG. 5, the temperature sensing portion 11a of the thermistor element 11 is covered with an organic substance 32 or an inorganic substance containing a radio wave absorber powder as a filler. An application for this sensor was filed in Japanese Patent Application No. 3-244449. The microwave sensor 10 shown in FIG. 6 has a metal encapsulation body 33 which is close to the thermistor element 11 and encloses the thermistor element 11 including its leads 11c, and a layer on the surface of the metal encapsulation body 33. The formed radio wave absorber 12
With. The thermistor element 11 is preferably fixed in the metal envelope 33 by a filler 36. An application for this sensor was filed in Japanese Patent Application No. 4-100348.

【0016】図7に示されるマイクロ波センサ10は、
電波吸収体12がサーミスタ特性を有し、この電波吸収
体12のマイクロ波を受けない面に一対の電極42,4
3が間隔をあけて設けられる。電極42,43にはリー
ド44,46がそれぞれ接続され、電波吸収体12はリ
ード44,46を被包するセラミック被包体47を介し
てキャップ状の取付体48に取付けられる。このセンサ
に関して特願平4−100349号により出願した。図
8に示されるマイクロ波センサ10は、電波吸収体12
がサーミスタ素子11に近接してこのサーミスタ素子1
1をそのリード11cを含めて被包する。電波吸収体1
2は金属製の鍔部54を介して取付けられる。サーミス
タ素子11は充填材36により電波吸収体12内で固定
されることが好ましい。このセンサに関して特願平4−
100350号により出願した。図9に示されるマイク
ロ波センサ10は、電波吸収体12の表面をマイクロ波
を受ける面とし、この電波吸収体12の裏面のマイクロ
波を受けない位置に金属体56が金属層58を介して接
合され、サーミスタ素子11がこの金属体56により保
持されかつ電波吸収体12の温度を金属体56を介して
感知する。サーミスタ素子11のリード11cは絶縁性
物質で被覆される。このセンサに関して特願平4−16
3582により出願した。
The microwave sensor 10 shown in FIG.
The radio wave absorber 12 has thermistor characteristics, and a pair of electrodes 42, 4 is provided on the surface of the radio wave absorber 12 that does not receive microwaves.
3 are provided at intervals. Leads 44 and 46 are connected to the electrodes 42 and 43, respectively, and the electromagnetic wave absorber 12 is attached to a cap-shaped attachment body 48 via a ceramic enclosure 47 that encloses the leads 44 and 46. An application for this sensor was filed in Japanese Patent Application No. 4-100349. The microwave sensor 10 shown in FIG.
Is close to the thermistor element 11 and the thermistor element 1
1 is encapsulated including its lead 11c. Radio wave absorber 1
2 is attached via a collar 54 made of metal. The thermistor element 11 is preferably fixed in the radio wave absorber 12 by a filling material 36. Japanese Patent Application No. 4-
Filed under No. 100350. In the microwave sensor 10 shown in FIG. 9, the front surface of the radio wave absorber 12 is a surface that receives microwaves, and the metal body 56 is provided on the back surface of the radio wave absorber 12 at a position where it does not receive microwaves via the metal layer 58. The thermistor element 11 is joined and held by the metal body 56 and senses the temperature of the radio wave absorber 12 through the metal body 56. The leads 11c of the thermistor element 11 are covered with an insulating material. Regarding this sensor, Japanese Patent Application No. 4-16
Filed under 3582.

【0017】[0017]

【発明の効果】以上述べたように、本発明では、前記式
(1)の関係及びマイクロ波センサの熱放散定数δとそ
の熱時定数τを予め計算装置に入力しておき、このδと
τでマイクロ波センサの熱放散を考慮するようにして、
マイクロ波センサではマイクロ波の吸収に伴う熱エネル
ギを検出するように構成したので、正確にエネルギ量を
検出できるとともに、従来のようにマイクロ波センサに
熱放散を防止する熱絶縁体を設けずに済む。また、計算
装置が時間の経過に従ってマイクロ波エネルギを求める
ため、その変化に基づきマイクロ波源の出力を制御すれ
ば、被加熱物を所望の解凍状態又は加熱状態に的確に処
理することができる。
As described above, according to the present invention, the relation of the equation (1), the heat dissipation constant δ of the microwave sensor and its thermal time constant τ are input to the calculation device in advance, and this δ Considering the heat dissipation of the microwave sensor with τ,
Since the microwave sensor is configured to detect the thermal energy associated with the absorption of microwaves, it is possible to accurately detect the amount of energy, and without providing the microwave sensor with a heat insulator that prevents heat dissipation as in the conventional case. I'm done. Further, since the calculation device obtains the microwave energy with the passage of time, if the output of the microwave source is controlled based on the change, the object to be heated can be appropriately processed into the desired defrosting state or heating state.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明実施例のマイクロ波エネルギ検出装置の
構成図。
FIG. 1 is a configuration diagram of a microwave energy detection device according to an embodiment of the present invention.

【図2】そのマイクロ波センサの断面図。FIG. 2 is a sectional view of the microwave sensor.

【図3】被加熱物のないときに検出装置が検出したエネ
ルギ量の変化を示す図。
FIG. 3 is a diagram showing changes in the amount of energy detected by a detection device when there is no object to be heated.

【図4】氷を解凍したときに検出装置が検出したエネル
ギ量の変化を示す図。
FIG. 4 is a diagram showing changes in the amount of energy detected by a detection device when ice is thawed.

【図5】そのマイクロ波センサの別の断面図。FIG. 5 is another sectional view of the microwave sensor.

【図6】そのマイクロ波センサの別の断面図。FIG. 6 is another sectional view of the microwave sensor.

【図7】そのマイクロ波センサの別の断面図。FIG. 7 is another sectional view of the microwave sensor.

【図8】そのマイクロ波センサの別の断面図。FIG. 8 is another sectional view of the microwave sensor.

【図9】そのマイクロ波センサの別の断面図。FIG. 9 is another sectional view of the microwave sensor.

【図10】断熱状態において物質がマイクロ波エネルギ
を受けたときの温度変化図。
FIG. 10 is a temperature change diagram when a substance receives microwave energy in an adiabatic state.

【図11】熱放散がある状態において物質がマイクロ波
エネルギを受けたときの温度変化図。
FIG. 11 is a temperature change diagram when a substance receives microwave energy in the state where heat is dissipated.

【図12】このときの時間に対する温度の一次導関数を
示す図。
FIG. 12 is a graph showing the first derivative of temperature with respect to time at this time.

【図13】このときの時間に対する温度の二次導関数を
示す図。
FIG. 13 is a diagram showing a second derivative of temperature with respect to time at this time.

【符号の説明】[Explanation of symbols]

10 マイクロ波センサ 11 サーミスタ素子 11a 感温部 11c リード 12 電波吸収体 12a 電波吸収体の一方の面 12b 電波吸収体の他方の面 30 コントローラ(計算装置) 10 Microwave Sensor 11 Thermistor Element 11a Temperature Sensing Section 11c Lead 12 Radio Wave Absorber 12a One Side of Radio Wave Absorber 12b Other Side of Radio Wave Absorber 30 Controller (Calculator)

Claims (7)

【特許請求の範囲】[Claims] 【請求項1】 マイクロ波を吸収して発熱する電波吸収
体(12)と前記吸収体(12)の温度を検出するサーミスタ素
子(11)とを有するマイクロ波センサ(10)と、 前記マイクロ波センサ(10)の検出出力に基づいてマイク
ロ波エネルギの値を計算する計算装置(30)とを備えたマ
イクロ波エネルギ検出装置であって、 前記計算装置(30)は、下記式(1)によりマイクロ波エ
ネルギの値を時間の関数として計算することを特徴とす
るマイクロ波エネルギ検出装置。 E = C・dθ/dt + δ・θ (1) ただし、Eは前記電波吸収体が吸収したマイクロ波エネ
ルギ、θは前記サーミスタ素子が検出する温度上昇値、
Cは前記マイクロ波センサの熱容量、δは前記マイクロ
波センサの熱放散定数である。
1. A microwave sensor (10) having a radio wave absorber (12) that absorbs microwaves to generate heat and a thermistor element (11) that detects the temperature of the absorber (12); A microwave energy detection device comprising: a calculation device (30) for calculating a value of microwave energy based on a detection output of a sensor (10), wherein the calculation device (30) is represented by the following formula (1). A microwave energy detecting device, characterized in that the value of microwave energy is calculated as a function of time. E = C · dθ / dt + δ · θ (1) where E is the microwave energy absorbed by the radio wave absorber, θ is the temperature rise value detected by the thermistor element,
C is the heat capacity of the microwave sensor, and δ is the heat dissipation constant of the microwave sensor.
【請求項2】 マイクロ波センサ(10)は電波吸収体(12)
が少なくともサーミスタ素子(11)の感温部(11a)より広
い面積を有する平板状に形成され、前記電波吸収体の一
方の面(12a)がマイクロ波吸収面であって、前記電波吸
収体の他方の面(12b)に前記サーミスタ素子(11)がマイ
クロ波を受けないように前記感温部(11a)が接着された
請求項1記載のマイクロ波エネルギ検出装置。
2. The microwave sensor (10) is a radio wave absorber (12).
Is formed in a flat plate shape having a larger area than at least the temperature sensing part (11a) of the thermistor element (11), and one surface (12a) of the radio wave absorber is a microwave absorbing surface, 2. The microwave energy detecting device according to claim 1, wherein the temperature sensing part (11a) is adhered to the other surface (12b) so that the thermistor element (11) does not receive microwaves.
【請求項3】 マイクロ波センサ(10)はサーミスタ素子
(11)の感温部(11a)が電波吸収体粉末を充填材として含
む有機物質(32)又は無機物質により被覆された請求項1
記載のマイクロ波エネルギ検出装置。
3. The microwave sensor (10) is a thermistor element.
The temperature sensing part (11a) of (11) is covered with an organic substance (32) or an inorganic substance containing a radio wave absorber powder as a filler.
Microwave energy detection device as described.
【請求項4】 マイクロ波センサ(10)はサーミスタ素子
(11)に近接して前記サーミスタ素子(11)をそのリード(1
1c)を含めて被包する金属被包体(33)と、前記金属被包
体(33)の表面に層状に形成された電波吸収体(12)とを備
えた請求項1記載のマイクロ波エネルギ検出装置。
4. The microwave sensor (10) is a thermistor element.
Connect the thermistor element (11) to its lead (1
The microwave according to claim 1, further comprising: a metal encapsulant (33) encapsulating the metal encapsulation (1c), and a radio wave absorber (12) formed in layers on the surface of the metal encapsulant (33). Energy detection device.
【請求項5】 マイクロ波センサ(10)は電波吸収体(12)
がサーミスタ特性を有し、前記電波吸収体(12)のマイク
ロ波を受けない面に一対の電極(42,43)が間隔をあけて
設けられた請求項1記載のマイクロ波エネルギ検出装
置。
5. The microwave sensor (10) is a radio wave absorber (12).
2. The microwave energy detecting apparatus according to claim 1, wherein said microwave absorber has a thermistor characteristic, and a pair of electrodes (42, 43) are provided at intervals on a surface of said radio wave absorber (12) which does not receive microwaves.
【請求項6】 マイクロ波センサ(10)は電波吸収体(12)
がサーミスタ素子(11)に近接して前記サーミスタ素子(1
1)をそのリード(11c)を含めて被包する請求項1記載の
マイクロ波エネルギ検出装置。
6. The microwave sensor (10) is a radio wave absorber (12).
Is close to the thermistor element (11) and the thermistor element (1
The microwave energy detecting device according to claim 1, wherein the lead (11c) is encapsulated in (1).
【請求項7】 マイクロ波センサ(10)は電波吸収体(12)
の表面をマイクロ波を受ける面とし、前記電波吸収体(1
2)の裏面のマイクロ波を受けない位置に金属体(56)が接
合され、サーミスタ素子(11)が前記金属体(56)により保
持されかつ前記電波吸収体(12)の温度を前記金属体(56)
を介して感知する請求項1記載のマイクロ波エネルギ検
出装置。
7. The microwave sensor (10) is a radio wave absorber (12).
The surface of the electromagnetic wave absorber (1
The metal body (56) is bonded to the back surface of 2) at a position where it does not receive microwaves, the thermistor element (11) is held by the metal body (56), and the temperature of the radio wave absorber (12) is controlled by the metal body. (56)
The microwave energy detecting apparatus according to claim 1, wherein the microwave energy detecting apparatus detects the energy through a microwave.
JP4202037A 1991-12-25 1992-07-06 Microwave energy detector Expired - Lifetime JPH0827314B2 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
JP4202037A JPH0827314B2 (en) 1992-07-06 1992-07-06 Microwave energy detector
US07/989,173 US5378875A (en) 1991-12-25 1992-12-11 Microwave oven with power detecting device
CA002085527A CA2085527C (en) 1991-12-25 1992-12-16 Microwave power detecting device
NL9202189A NL193485C (en) 1991-12-25 1992-12-17 Microwave oven.
GB9226657A GB2263173B (en) 1991-12-25 1992-12-22 Microwave power detecting device
DE4243597A DE4243597C2 (en) 1991-12-25 1992-12-22 Microwave power detection device
FR9215873A FR2685772A1 (en) 1991-12-25 1992-12-23 MICROWAVE ENERGY DETECTOR DEVICE.
KR1019920025659A KR970002015B1 (en) 1991-12-25 1992-12-24 Microwave power detecting device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4202037A JPH0827314B2 (en) 1992-07-06 1992-07-06 Microwave energy detector

Publications (2)

Publication Number Publication Date
JPH0627166A true JPH0627166A (en) 1994-02-04
JPH0827314B2 JPH0827314B2 (en) 1996-03-21

Family

ID=16450892

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4202037A Expired - Lifetime JPH0827314B2 (en) 1991-12-25 1992-07-06 Microwave energy detector

Country Status (1)

Country Link
JP (1) JPH0827314B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6962111B2 (en) 2000-06-15 2005-11-08 Murata Manufacturing Co., Ltd. Screen-printing plate, manufacturing method of laminated-ceramic electronic devices, and laminated-ceramic electronic device manufactured by the method
CN111638115A (en) * 2014-05-16 2020-09-08 比奥利弗解决方案公司 System, device and method for automatic sample thawing

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5812017A (en) * 1981-07-14 1983-01-24 Daikin Ind Ltd Flow rate and pressure controller
JPS62119635U (en) * 1986-01-22 1987-07-29
JPH02300671A (en) * 1989-03-30 1990-12-12 Luxtron Corp Method and apparatus for measuring intensity of microwave electric field and power existing partially using optical fiber art

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5812017A (en) * 1981-07-14 1983-01-24 Daikin Ind Ltd Flow rate and pressure controller
JPS62119635U (en) * 1986-01-22 1987-07-29
JPH02300671A (en) * 1989-03-30 1990-12-12 Luxtron Corp Method and apparatus for measuring intensity of microwave electric field and power existing partially using optical fiber art

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6962111B2 (en) 2000-06-15 2005-11-08 Murata Manufacturing Co., Ltd. Screen-printing plate, manufacturing method of laminated-ceramic electronic devices, and laminated-ceramic electronic device manufactured by the method
CN111638115A (en) * 2014-05-16 2020-09-08 比奥利弗解决方案公司 System, device and method for automatic sample thawing

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