JP4260145B2

JP4260145B2 - rice cooker

Info

Publication number: JP4260145B2
Application number: JP2005238673A
Authority: JP
Inventors: 知哉中山; 定宇都宮
Original assignee: Zojirushi Corp
Current assignee: Zojirushi Corp
Priority date: 2005-08-19
Filing date: 2005-08-19
Publication date: 2009-04-30
Anticipated expiration: 2025-08-19
Also published as: JP2007050167A

Description

本発明は、加熱ヒータを有する加熱板を用いた直接加熱方式の炊飯器に関するものである。 The present invention relates to a direct heating type rice cooker using a heating plate having a heater.

この種の炊飯器は、炊飯鍋を収容する炊飯器本体と、該炊飯器本体に開閉可能に取り付けられた蓋体とを備えている。前記炊飯器本体の内部には、炊飯鍋を加熱する加熱手段と、炊飯鍋の温度を検出する鍋用温度センサとが配設されている。また。蓋体の内部には、炊飯鍋の上部の空間温度を検出する蓋用温度センサが配設されている。そして、これら温度センサの検出値に基づいて、炊飯鍋内にセットした飯米を予熱、昇温、沸騰維持、および、むらしの各工程を実行して炊飯処理を行う。 This type of rice cooker includes a rice cooker body that houses a rice cooker and a lid that is attached to the rice cooker body so as to be openable and closable. Inside the rice cooker body, heating means for heating the rice cooker and a temperature sensor for the pan for detecting the temperature of the rice cooker are arranged. Also. A lid temperature sensor for detecting the space temperature of the upper portion of the rice cooker is disposed inside the lid. And based on the detected value of these temperature sensors, the rice cooking set in the rice cooking pan is performed by performing the steps of preheating, heating, boiling maintenance, and unevenness.

しかし、炊飯器本体において、炊飯鍋と収容部との間に異物が混入している場合には、温度センサによって正確な温度を検出できないため、飯米の炊き上げ状態に不具合が生じるという問題がある。 However, in the rice cooker main body, when a foreign object is mixed between the rice cooker and the container, the temperature sensor cannot detect the exact temperature, so there is a problem that the cooked state of the rice rice has a problem. .

この問題に鑑みて、異物の混入状態でもご飯を炊き上げることができるようにした炊飯器に関連する先行技術文献情報としては次のものがある。 In view of this problem, there is the following as prior art document information related to a rice cooker that can cook rice even in a mixed state of foreign matters.

特開平７−５１１５９号公報JP-A-7-51159 特開平７−１５５２５１号公報JP-A-7-155251 特開平７−１７７９６７号公報JP 7-177967 A

これら特許文献の炊飯器では、加熱手段として誘導加熱コイルによって炊飯鍋を誘導加熱する炊飯器において、異物の混入による異常加熱により飯米が焦げた状態で炊飯されることを防止できる構成としている。具体的には、この誘導加熱方式の炊飯器の場合、炊飯鍋との間に異物が混入すると、温度検出手段による検出値が実際の温度より低くなる。そのため、誘導加熱コイルによって加熱する時間が長くなり、炊飯鍋内の飯米を焦がしてしまう。そこで、このような異物の混入状態での過剰加熱を防止するために、異物が混入していない通常炊飯時の所定の制御を行うことなく、カットして次工程に移行することにより、ユーザが食べることが可能な状態で炊き上げる構成としている。 In the rice cooker of these patent documents, it is set as the structure which can prevent rice rice being cooked in the state which burned by the abnormal heating by mixing of a foreign material in the rice cooker which induction-heats a rice cooking pot with an induction heating coil as a heating means. Specifically, in the case of this induction heating type rice cooker, if a foreign object is mixed with the rice cooker, the detected value by the temperature detecting means becomes lower than the actual temperature. Therefore, the time to heat with an induction heating coil becomes long, and the cooked rice in a rice cooker will be burnt. Therefore, in order to prevent overheating in the mixed state of such foreign matter, the user can cut and move to the next process without performing predetermined control during normal cooking without foreign matter mixed in. It is configured to cook in a state where it can be eaten.

しかしながら、これらの引用文献は、誘導加熱方式の炊飯器であるため、加熱ヒータを内蔵した加熱板による直接加熱方式の炊飯器には適用することはできない。即ち、この直接加熱方式の炊飯器の場合、炊飯鍋との間に異物が混入すると、加熱板の熱を伝熱により炊飯鍋に伝えることができないため、その周囲が異常高温になる。そして、温度検出手段による検出値は実際より高くなるため、沸騰維持工程に移行すると、直後に沸騰維持工程の終了を意味するドライアップ状態と同等の温度を検出することになるため、直ぐにむらし工程に移行（以下「早切れ」と称する。）する。その結果、米に対して十分に火力を加えることができないため、炊き上げ状態が悪くなる。 However, since these cited references are induction heating type rice cookers, they cannot be applied to a direct heating type rice cooker using a heating plate incorporating a heater. That is, in the case of this direct heating type rice cooker, if a foreign object is mixed with the rice cooker, the heat of the heating plate cannot be transferred to the rice cooker by heat transfer, so the surroundings become abnormally hot. And since the detection value by the temperature detection means becomes higher than the actual value, immediately after shifting to the boiling maintenance process, a temperature equivalent to the dry-up state, which means the end of the boiling maintenance process, is detected. Transition to the process (hereinafter referred to as “early cut”). As a result, it is not possible to apply sufficient thermal power to the rice, so the cooked state becomes worse.

本発明では、加熱板を用いた直接加熱方式の炊飯器において、異物混入時の早切れを防止し、確実に炊飯可能とすることを課題とするものである。 In this invention, in the rice cooker of the direct heating system using a heating plate, it makes it a subject to prevent the premature break at the time of a foreign material mixing, and to enable rice cooking reliably.

前記課題を解決するため、本発明の第１の炊飯器は、炊飯鍋を収容する炊飯器本体と、内部に加熱ヒータを有し前記炊飯鍋を加熱する加熱板と、前記炊飯鍋内の温度を検出する温度検出手段とを備え、該温度検出手段の検出値に基づいて前記加熱板を制御して、米に吸水させる予熱工程、炊飯鍋内の水が沸騰するまで加熱する昇温工程、該昇温工程より弱い加熱力で沸騰状態を維持する沸騰維持工程、および、米を蒸らすむらし工程を有する炊飯制御を実行する炊飯器において、前記沸騰維持工程は、前記温度検出手段の検出値が予め設定した移行温度に達するとむらし工程へ移行するもので、昇温工程での加熱に伴う余熱を無くすように、前記加熱ヒータへの通電を前記昇温工程より弱い加熱力より更に抑制し、むらし工程への移行判断を実行しない第１工程と、前記加熱ヒータへの通電を抑制することなく前記昇温工程より弱い加熱力で加熱し、むらし工程への移行判断を実行し、前記温度検出手段の検出値が移行温度に達するとむらし工程へ移行させる第２工程とを備え、前記第２工程の実行直後に、前記温度検出手段の検出値に拘わらずむらし工程への移行を禁止し、前記温度検出手段の検出値を移行温度より下回らせる移行禁止時間帯を更に設け、該移行禁止時間帯外では、温度検出手段の検出値と移行温度とに基づいてむらし工程への移行を許容する構成としている。
In order to solve the above-mentioned problems, the first rice cooker of the present invention includes a rice cooker body that houses a rice cooker, a heating plate that has a heater inside and heats the rice cooker, and the temperature in the rice cooker. A temperature detecting means for detecting the temperature, and a heating step for controlling the heating plate based on the detected value of the temperature detecting means so that the rice absorbs water, heating the rice cooking pot until the water is boiled, In the rice cooker which performs the rice cooking control which has the boiling maintenance process which maintains a boiling state with weak heating power than this temperature rising process, and the unevenness process which steams rice, the boiling maintenance process is a detection value of the temperature detection means. When the transition temperature reaches a preset transition temperature, the process shifts to the uneven process, and the energization of the heater is further suppressed from the weaker heating power than the temperature increase process so as to eliminate the residual heat accompanying the heating in the temperature increase process. and, the migration decision to the steaming process The heating with a weak heating power than heating step without inhibiting the first step not to row, the energization of the heater, to perform a shift determination to steaming step, the detection value of the temperature detection means migration A second step of shifting to the unevenness process when the temperature is reached, and immediately after the execution of the second step , the transition to the unevenness process is prohibited regardless of the detection value of the temperature detection means, and the temperature detection means Further, a transition prohibition time zone for lowering the detected value below the transition temperature is provided, and outside the transition prohibition time zone, the transition to the uneven process is allowed based on the detection value of the temperature detection means and the transition temperature . .

また、本発明の第２の炊飯器は、前記第２工程では、前記第１工程での抑制加熱によって前記温度検出手段による検出値が下降勾配であるとむらし工程への移行を禁止し、第２工程での加熱により上昇勾配に至ると、温度検出手段の検出値と移行温度とに基づいてむらし工程への移行を許容する構成としている。
Moreover, the 2nd rice cooker of this invention prohibits the transfer to the uneven process in the said 2nd process, when the detected value by the said temperature detection means is a downward gradient by the suppression heating in the said 1st process . When a rising gradient is reached by heating in the second step, the transition to the unevenness step is allowed based on the detected value of the temperature detection means and the transition temperature .

本発明の炊飯器では、沸騰維持工程の第２工程において、移行禁止時間帯が経過するまで次工程への移行を禁止し、または、検出値が上昇勾配になるまで次工程への移行を禁止しているため、第１工程を含むその移行禁止間に加熱板の周囲の温度を迅速に降下させることができる。また、第２工程では、昇温工程より弱い加熱力で炊飯鍋を加熱するため、急激に温度が上昇することはない。その結果、炊飯鍋と加熱板との間に若干の異物が混入していても早切れすることなく、確実に食べることが可能な炊き上げ状態を確保できる。
In the rice cooker of the present invention, in the second step of the boiling maintenance process, the transition to the next process is prohibited until the transition prohibition time period elapses, or the transition to the next process is prohibited until the detected value becomes an upward gradient. Therefore, the temperature around the heating plate can be quickly lowered during the transition prohibition including the first step. Moreover, in the 2nd process, since a rice cooker is heated with a heating power weaker than a temperature rising process, temperature does not rise rapidly. As a result, even if some foreign matter is mixed between the rice cooker and the heating plate, a cooked state that can be surely eaten can be secured without being cut quickly.

以下、本発明の実施の形態を図面に従って説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１および図２は、本発明の第１実施形態に係る炊飯器１０を示す。この炊飯器１０は、炊飯鍋１１を着脱可能に収容する炊飯器本体１２と、該炊飯器本体１２の上端開口を閉塞する蓋体２１とを備えたものである。 1 and 2 show a rice cooker 10 according to a first embodiment of the present invention. The rice cooker 10 includes a rice cooker body 12 that detachably accommodates the rice cooker 11 and a lid 21 that closes the upper end opening of the rice cooker body 12.

前記炊飯器本体１２には、炊飯鍋１１を装着する開口から円筒状の内胴１３が配設され、この内胴１３の底が遮熱板１４により閉塞されている。また、この内胴１３の内部には、第１の加熱手段を構成する加熱板１５が配設されている。この加熱板１５は、内部に加熱ヒータ１６を配設した略椀形状のもので、伝熱性がよいアルミ材料により形成されている。また、この加熱板１５の中央部には貫通孔１７が設けられ、この貫通孔１７を通して上部に載置された炊飯鍋１１の温度を検出できるように第１の温度検出手段である鍋用温度センサ１８が配設されている。また、この炊飯器本体１２には、内部にマイコン２９を実装した図示しない制御基板が配設されるとともに、液晶パネルなどの表示手段１９および複数のスイッチからなる入力手段２０が配設されている。 The rice cooker body 12 is provided with a cylindrical inner cylinder 13 from an opening in which the rice cooker 11 is mounted, and the bottom of the inner cylinder 13 is closed by a heat shield plate 14. In addition, a heating plate 15 constituting a first heating means is disposed inside the inner cylinder 13. The heating plate 15 has a substantially bowl shape with a heater 16 disposed therein, and is formed of an aluminum material having good heat conductivity. In addition, a through hole 17 is provided in the center of the heating plate 15, and the temperature for the pan, which is the first temperature detecting means, can be detected through the through hole 17 so as to detect the temperature of the rice cooking pot 11. A sensor 18 is provided. The rice cooker main body 12 is provided with a control board (not shown) having a microcomputer 29 mounted therein, and a display means 19 such as a liquid crystal panel and an input means 20 including a plurality of switches. .

前記蓋体２１は、前記炊飯器本体１２に対して回転可能に取り付けられるもので、上板２２と、該上板２２の下部を閉塞する下板２３と、該下板２３の下面に設けられた内蓋２４とを備えている。この内蓋２４には、炊飯鍋１１の上部内周面との間をシールするパッキン２５が配設されている。また、上板２２と内蓋２４との間には、炊飯鍋１１内で発生した蒸気を排気するための排気ユニット２６が設けられている。さらに、内蓋２４の上部には、第２の加熱手段を構成する蓋ヒータ２７が配設されるとともに、炊飯鍋１１の上部空間部分の温度を検出するための第２の温度検出手段である蓋用温度センサ２８が配設されている。 The lid 21 is rotatably attached to the rice cooker body 12 and is provided on the upper plate 22, the lower plate 23 that closes the lower portion of the upper plate 22, and the lower surface of the lower plate 23. And an inner lid 24. The inner lid 24 is provided with a packing 25 that seals between the inner peripheral surface of the rice cooking pot 11. Further, an exhaust unit 26 for exhausting steam generated in the rice cooker 11 is provided between the upper plate 22 and the inner lid 24. Furthermore, a lid heater 27 that constitutes a second heating unit is disposed on the upper portion of the inner lid 24, and is a second temperature detection unit for detecting the temperature of the upper space portion of the rice cooker 11. A lid temperature sensor 28 is provided.

前記構成の炊飯器１０は、制御手段である前記マイコン２９により、内蔵した記憶手段であるＲＡＭに記憶されたプログラムに従って制御される。具体的には、入力手段２０の操作により炊飯制御が実行されると、米に吸水させる予熱工程、炊飯鍋１１内の水が沸騰するまで加熱する昇温工程、その沸騰状態を維持し炊飯鍋１１内の残水分を無くす炊き上げ（ドライアップ）を含む沸騰維持工程、および、蓄熱により炊き上げた米を蒸らすむらし工程からなる炊飯処理を実行した後、続いて保温処理を実行する。 The rice cooker 10 having the above-described configuration is controlled by the microcomputer 29, which is a control unit, according to a program stored in a RAM, which is a built-in storage unit. Specifically, when the rice cooking control is executed by the operation of the input means 20, a preheating step for absorbing water into the rice, a temperature raising step for heating until the water in the rice cooking pan 11 boils, and a rice cooking pan that maintains its boiling state. After performing the boiling maintenance process including the cooking (drying up) which eliminates the residual moisture in 11 and the rice cooking process consisting of the steaming process of steaming the rice cooked by heat storage, the heat retaining process is subsequently performed.

具体的には、図３および図４に「本願異物非混入時」として示すように、マイコン２９は、ステップＳ１で、予め設定された実行時間、蓋用温度センサ２８の検出値に基づいて加熱ヒータ１６をデューティー制御することにより、炊飯鍋１１内を米の吸水が促進される４０℃に維持する予熱工程を実行する。 Specifically, as shown in FIG. 3 and FIG. 4 as “when the foreign object of the present application is not mixed”, the microcomputer 29 performs heating based on the preset execution time and the detection value of the lid temperature sensor 28 in step S1. By performing duty control on the heater 16, a preheating step is performed to maintain the inside of the rice cooking pot 11 at 40 ° C. where water absorption of rice is promoted.

そして、この予熱工程が終了すると、ステップＳ２の鍋無し検知工程と、ステップＳ５の昇温工程とを並行して実行する。 And when this preheating process is complete | finished, the no pan detection process of step S2 and the temperature rising process of step S5 are performed in parallel.

ステップＳ２では、鍋用温度センサ１８の検出値に基づいて鍋無し検知工程を実行した後、ステップＳ３で、この検知工程による判断結果を示すフラグｆに１が入力されているか否かを検出する。そして、ｆが１（鍋無し判断）である場合にはステップＳ４に進み、炊飯処理の停止処理を実行して、全ての処理を停止した待機処理に移行する。また、ｆが０（鍋有り判断）である場合には、ステップＳ５の昇温工程が終了するまで待機してステップＳ６に進む。なお、本実施形態の鍋無し検知工程は、鍋用温度センサ１８によって予め設定した時間帯の温度の上昇勾配を算出し、予め設定した基準温度上昇勾配と比較することにより、炊飯鍋１１の装着の有無を判断するものである。 In step S2, after the pan absence detection step is executed based on the detection value of the pan temperature sensor 18, it is detected in step S3 whether or not 1 is input to the flag f indicating the determination result in the detection step. . And when f is 1 (no pot judgment), it progresses to step S4, the stop process of a rice cooking process is performed, and it transfers to the standby process which stopped all the processes. On the other hand, if f is 0 (determined that there is a pan), the process waits until the temperature raising process in step S5 is completed and proceeds to step S6. In addition, the no pan detection process of this embodiment calculates the temperature rising gradient in the preset time zone by the pan temperature sensor 18 and compares it with the preset reference temperature rising gradient, thereby mounting the rice cooking pot 11. The presence or absence of this is judged.

また、ステップＳ５では、蓋用温度センサ２８の検出値に基づいて炊飯鍋１１内が沸騰したと判断するまで、加熱ヒータ１６に対してフルパワーで通電する昇温工程を実行する。この昇温工程が終了すると、ステップＳ６で、鍋用温度センサ１８の検出値に基づいて昇温工程より弱い加熱力で加熱ヒータ１６をデューティー制御することにより、炊飯鍋１１内を沸騰状態に維持する沸騰維持工程を実行する。この沸騰維持工程が終了すると、ステップＳ７で、予め設定された実行時間、蓄熱により炊き上げた米を蒸らすむらし工程を実行する。これらの各工程を経て炊飯処理が終了すると、続いて保温処理に移行する。 Moreover, in step S5, the temperature rising process which energizes with the full power with respect to the heater 16 is performed until it judges that the inside of the rice cooking pot 11 boiled based on the detected value of the temperature sensor 28 for lid | covers. When this temperature raising process is completed, the inside of the rice cooking pan 11 is maintained in a boiling state by duty-controlling the heater 16 with a heating force weaker than that in the temperature raising process based on the detection value of the temperature sensor 18 for pots in step S6. The boiling maintenance process is performed. When this boiling maintenance process is completed, in step S7, a pre-run time and an uneven process of steaming rice cooked by heat storage are executed. When the rice cooking process is completed through these steps, the process proceeds to a heat retaining process.

前記沸騰維持工程は、図４に示すように、第１沸騰維持（第１工程）と、第２沸騰維持（第２工程）と、炊き上げとを有する。第１沸騰維持では、加熱ヒータ１６への通電を抑制することにより、前の昇温工程にてフルパワーで加熱したことに伴う余熱を無くし、鍋用温度センサ１８によって実際の炊飯鍋１１の温度を検出できるようにする。そして、この第１沸騰維持では、鍋用温度センサ１８の検出値に基づいて次工程であるむらし工程への移行判断は実行しないように構成している。第２沸騰維持では、加熱ヒータ１６への通電を抑制することなく、鍋用温度センサ１８の検出値に基づいてデューティー制御することにより、沸騰状態を確実に維持する。そして、この第２沸騰維持では、鍋用温度センサ１８の検出値に基づいて次工程であるむらし工程への移行判断を実行するように構成している。炊き上げは、第２沸騰維持により炊飯鍋１１内の水分が殆ど無くなることにより、該炊飯鍋１１内が沸点以上に昇温することにより実行され、確実に炊飯鍋１１内の残水分を無くす（ドライアップ）。そして、炊飯鍋１１と加熱板１５との間に異物が混入していない通常時には、この炊き上げ時にむらし工程への移行温度に達する。
The said boiling maintenance process has a 1st boiling maintenance (1st process), a 2nd boiling maintenance (2nd process), and cooking, as shown in FIG. In the first boiling maintenance, by suppressing energization to the heater 16, there is no residual heat due to heating at full power in the previous temperature raising step, and the temperature of the actual rice cooking pan 11 is measured by the pan temperature sensor 18. Can be detected. And in this 1st boiling maintenance, based on the detected value of the temperature sensor 18 for pans, it is comprised so that the transfer judgment to the uneven process which is the next process may not be performed. In the second boiling maintenance, the boiling state is reliably maintained by performing duty control based on the detection value of the pan temperature sensor 18 without suppressing energization to the heater 16. And in this 2nd boiling maintenance, based on the detected value of the temperature sensor 18 for pans, it is comprised so that the shift judgment to the uneven process which is the next process may be performed. The cooking is executed when the temperature in the rice cooking pot 11 is raised to the boiling point or higher by almost eliminating the water in the rice cooking pot 11 by maintaining the second boiling, and the residual moisture in the rice cooking pot 11 is surely eliminated ( Dry up). And at the normal time when the foreign material is not mixed between the rice cooking pan 11 and the heating plate 15, the transition temperature to the unevenness process is reached at the time of cooking.

従来では、鍋用温度センサ１８が加熱板１５を貫通されている構造上、図４に「従来異物混入時」として示すように、異物が混入している状態では、加熱板１５の熱を炊飯鍋１１に十分に伝えることができないため、その周囲が通常時より高温になる。そのため、鍋用温度センサ１８による検出値は通常時より高くなる。その結果、第２沸騰維持に移行すると、直後に沸騰維持工程の終了を意味するドライアップ状態と同等の温度を検出することになり、直ぐにむらし工程に移行する。この場合、米に対して十分に火力を加えることができていないため、炊き上げ状態が悪くなる。 Conventionally, due to the structure in which the pan temperature sensor 18 is passed through the heating plate 15, the heat of the heating plate 15 is cooked in the state where foreign matter is mixed as shown in FIG. Since it cannot fully convey to the pan 11, the surroundings becomes hotter than usual. Therefore, the detection value by the pan temperature sensor 18 is higher than normal. As a result, when shifting to the second boiling maintenance, immediately after that, a temperature equivalent to the dry-up state that means the end of the boiling maintenance process is detected, and the process immediately shifts to the unevenness process. In this case, since the heating power cannot be sufficiently applied to the rice, the cooked state becomes worse.

ここで、炊飯鍋１１と加熱板１５との間に混入した異物が大きい場合には、加熱板１５の熱が炊飯鍋１１に殆ど伝わらないため、鍋無しとして判断され、炊飯処理を最後まで実行することはできない。逆に、小さい場合には、鍋無しとしては判断できず、炊飯処理が最後まで続行されてしまう。そして、この小さい異物とは、使用上簡単に混入される可能性が高い米粒などの約２５ｍｍ^３のものを意味している。 Here, when the foreign material mixed between the rice cooking pan 11 and the heating plate 15 is large, since the heat of the heating plate 15 is hardly transmitted to the rice cooking pan 11, it is determined that there is no pan, and the rice cooking process is executed to the end. I can't do it. On the contrary, when it is small, it cannot be determined that there is no pan, and the rice cooking process is continued to the end. Then, a the small foreign matter, which means that approximately 25 mm ^3, such as are likely to be mixed on the easy-to-use rice grain.

そして、本実施形態では、第２沸騰維持に移行した直後の所定時間、鍋用温度センサ１８の検出値に拘わらず次工程であるむらし工程への移行を禁止する移行禁止時間帯を設け、この移行禁止時間帯以外のみ、鍋用温度センサ１８の検出値に基づいて次工程への移行を許否する構成としている。即ち、移行禁止時間が経過するまではむらし工程への移行を禁止し、経過後には移行を許容する構成としている。言い換えれば、移行禁止時間が経過するまでは、むらし工程への移行判断自体を実行せず、または、実行して移行条件を満たしていても移行させない。そして、移行禁止時間が経過すると、むらし工程への移行判断を実行し、移行条件を満たすと移行させる。そのため、炊飯鍋１１と加熱板１５との間に若干の異物が混入していても早切れすることなく、確実に食べることが可能な炊き上げ状態を確保できる。 And in this embodiment, a transition prohibition time zone for prohibiting the transition to the next step, the uneven process, is provided regardless of the detection value of the pan temperature sensor 18 for a predetermined time immediately after the transition to the second boiling maintenance, Only in the transition prohibition time zone, the transition to the next process is permitted based on the detection value of the pan temperature sensor 18. That is, the transition to the uneven process is prohibited until the transition prohibition time elapses, and the transition is permitted after the transition prohibition time has elapsed. In other words, until the transition prohibition time has elapsed, the transition judgment to the uneven process itself is not executed, or even if the transition condition is satisfied and the transition condition is satisfied, the transition is not performed. Then, when the transition prohibition time has elapsed, a transition determination to the uneven process is executed, and transition is performed when the transition condition is satisfied. Therefore, even if some foreign matters are mixed between the rice cooker 11 and the heating plate 15, a cooked state that can be surely eaten can be secured without being cut quickly.

具体的には、異物混入状態では、加熱板１５と炊飯鍋１１とが十分に接触していないため、前述のように、強加熱時には前述のように伝熱不良により異常高温となる。逆に、加熱停止時は勿論、加熱を抑制した低加熱時には、炊飯鍋１１の蓄熱が伝熱されないため、温度降下も大きい。そのため、移行を禁止する時間としては、約４０秒程度で次工程への移行温度を下回る。そこで、本実施形態では、若干の誤差を加味して移行禁止時間帯を６０秒に設定している。一方、第２沸騰維持では、昇温工程より弱い加熱力で炊飯鍋１１を加熱するため、一旦降下した温度は、急激に温度が上昇することはない。その結果、異物が混入していない通常時と略同様の時間、炊飯鍋１１に対して加熱力を加えることが可能になり、確実に炊飯の目的を達成できる。 Specifically, in the foreign matter mixed state, the heating plate 15 and the rice cooker 11 are not sufficiently in contact with each other, and as described above, during the strong heating, the heat transfer is abnormally high as described above. Conversely, not only when heating is stopped, but also during low heating while suppressing heating, the stored heat in the rice cooking pot 11 is not transferred, so the temperature drop is also large. Therefore, the time for prohibiting the transition is less than the transition temperature to the next process in about 40 seconds. Therefore, in the present embodiment, the transition prohibition time zone is set to 60 seconds with some errors added. On the other hand, in the 2nd boiling maintenance, since the rice cooking pot 11 is heated with a heating power weaker than the temperature raising step, the temperature once lowered does not rise rapidly. As a result, it becomes possible to apply a heating force to the rice cooking pot 11 for substantially the same time as normal time in which no foreign matter is mixed, and the purpose of rice cooking can be reliably achieved.

図５は第２実施形態の炊飯器１０の制御を示す。この第２実施形態では、予め設定した時間や温度の変わりに、鍋用温度センサ１８によって検出した温度の勾配によって次工程への移行を許否する構成とした点で第１実施形態と相違している。具体的には、第２沸騰維持では、鍋用温度センサ１８によって５秒毎に温度を検出し、その検出値（Ｔ_ｎ）が前回の検出値（Ｔ_ｎ−１）より高いか否かを検出する。そして、Ｔ_ｎ−１≧Ｔ_ｎの場合にはむらし工程への移行を禁止した状態を維持し、Ｔ_ｎ−１＜Ｔ_ｎの場合には以後のむらし工程への移行を許容する構成としている。言い換えれば、第１沸騰維持での抑制加熱により、検出値が下降勾配である場合には、むらし工程への移行判断自体を実行せず、または、実行して移行条件を満たしていても移行させない。そして、検出値が上昇勾配になると、むらし工程への移行判断を実行し、移行条件を満たすと移行させる。このようにしても、第１実施形態と同様に、炊飯鍋１１と加熱板１５との間に若干の異物が混入していても早切れすることなく、確実に食べることが可能な炊き上げ状態を確保できる。
FIG. 5 shows the control of the rice cooker 10 of the second embodiment . The second embodiment is different from the first embodiment in that the transition to the next process is permitted by the temperature gradient detected by the pan temperature sensor 18 instead of the preset time and temperature. Yes. Specifically, in the second boiling maintained, and detects the temperature by pan temperature sensor 18 every 5 seconds, whether the detected value (T _n) is higher than or the previous detection value (T _n-1) To detect. When T _n−1 ≧ T _n , the state where the transition to the uneven process is prohibited is maintained, and when T _n−1 <T _n , the transition to the subsequent uneven process is allowed. Yes. In other words, when the detected value is a descending gradient due to the suppression heating in the first boiling maintenance, the transition judgment to the unevenness process itself is not performed, or the transition is performed even if the transition condition is satisfied. I won't let you. When the detection value is rising slope, run the migration decision to steaming step shifts the transition condition is satisfied. Even if it does in this way, like the first embodiment , even if some foreign matter is mixed between the rice cooker 11 and the heating plate 15, the cooked state that can be surely eaten without being cut quickly. Can be secured.

なお、本発明の炊飯器１０は、前記実施形態の構成に限定されるものではなく、種々の変更が可能である。 In addition, the rice cooker 10 of this invention is not limited to the structure of the said embodiment, A various change is possible.

本発明に係る実施形態の炊飯器を示す概略断面図である。It is a schematic sectional drawing which shows the rice cooker of embodiment which concerns on this invention. 炊飯器の構成を示すブロック図である。It is a block diagram which shows the structure of a rice cooker. マイコンによる炊飯処理を示すフローチャートである。It is a flowchart which shows the rice cooking process by a microcomputer. 第１実施形態の炊飯処理時の各工程の温度遷移および制御を示すグラフである。It is a graph which shows the temperature transition and control of each process at the time of the rice cooking process of 1st Embodiment. 第２実施形態の炊飯処理時の各工程の温度遷移および制御を示すグラフである。 It is a graph which shows the temperature transition and control of each process at the time of the rice cooking process of 2nd Embodiment .

Explanation of symbols

１０…炊飯器
１１…炊飯鍋
１２…炊飯器本体
１５…加熱板
１６…加熱ヒータ
１８…鍋用温度センサ（温度検出手段）
２１…蓋体
２９…マイコン（制御手段） DESCRIPTION OF SYMBOLS 10 ... Rice cooker 11 ... Rice cooker 12 ... Rice cooker main body 15 ... Heating plate 16 ... Heating heater 18 ... Temperature sensor (temperature detection means) for pans
21 ... Lid 29 ... Microcomputer (control means)

Claims

A rice cooker body that houses the rice cooker, a heating plate that has a heater inside and heats the rice cooker, and a temperature detection means that detects the temperature in the rice cooker, the detection value of the temperature detection means The heating plate is controlled based on the preheating process for absorbing water in the rice, the heating process for heating until the water in the rice cooker boils, the boiling maintaining process for maintaining the boiling state with a heating power weaker than the heating process And in the rice cooker which performs rice cooking control which has an uneven process which steams rice,
The boiling maintaining step moves to the unevenness step when the detected value of the temperature detecting means reaches a preset transition temperature,
A first step in which energization of the heater is further suppressed from a heating power weaker than that in the temperature raising step so as to eliminate residual heat associated with heating in the temperature raising step, and the judgment to shift to the unevenness step is not performed;
Heating with a heating power weaker than that of the temperature raising step without suppressing energization to the heater, performing a transition judgment to the unevenness step , and when the detected value of the temperature detecting means reaches the transition temperature, the unevenness step A second step of shifting to
Immediately after execution of the second step , a transition prohibition time zone is further provided in which the transition to the unevenness step is prohibited regardless of the detection value of the temperature detection means, and the detection value of the temperature detection means is lower than the transition temperature , Outside the transition prohibition time zone, the rice cooker is characterized in that the transition to the unevenness process is allowed based on the detection value of the temperature detection means and the transition temperature .

A rice cooker body that houses the rice cooker, a heating plate that has a heater inside and heats the rice cooker, and a temperature detection means that detects the temperature in the rice cooker, the detection value of the temperature detection means The heating plate is controlled based on the preheating process for absorbing water in the rice, the heating process for heating until the water in the rice cooker boils, the boiling maintaining process for maintaining the boiling state with a heating power weaker than the heating process And in the rice cooker which performs rice cooking control which has an uneven process which steams rice,
The boiling maintaining step moves to the unevenness step when the detected value of the temperature detecting means reaches a preset transition temperature,
A first step in which energization of the heater is further suppressed from a heating power weaker than that in the temperature raising step so as to eliminate residual heat associated with heating in the temperature raising step, and the judgment to shift to the unevenness step is not performed;
Heating with a heating power weaker than that of the temperature raising step without suppressing energization to the heater, performing a transition judgment to the unevenness step , and when the detected value of the temperature detecting means reaches the transition temperature, the unevenness step A second step of shifting to
In the second step, when the detected value by the temperature detecting means is a descending gradient due to the suppression heating in the first step, the transition to the unevenness step is prohibited, and when the rising value is reached by the heating in the second step The rice cooker characterized by allowing the transition to the unevenness process based on the detection value of the temperature detection means and the transition temperature .