JP3660986B2 - Drainage amount measuring means, automatic liquid supply method and automatic liquid supply device in nutrient solution cultivation using the drainage amount measuring means, and nutrient solution cultivation method and nutrient solution cultivation apparatus using the same - Google Patents

Description

【０００１】
【発明の属する技術分野】
本発明は、排液量測定手段と、該排液量測定手段を用いた養液栽培における自動給液方法と自動給液装置、並びにこれを用いた養液栽培方法と養液栽培装置に関する。さらに詳しくは、本発明は、養液栽培ベッドから排出される余剰の培養液（排液）について微小な排液量が精度高く連続的に測定できる排液量測定手段と、該排液量測定手段を用いて、園芸作物の生育不良や収量低下を伴うことなく、園芸作物の生育に応じて適量の培養液を自動給液することのできる方法と装置、並びにそのような自動給液方法と自動給液装置とを用いて、肥料や水の節約及び使用済み培養液の排出量を削減させて、効率よく園芸作物を養液栽培することのできる方法と装置に関する。
【０００２】
【従来の技術】
蔬菜及び花卉などの園芸作物の生産にあたり、ロックウール耕をはじめとする養液栽培の割合が増加してきている。一般的に、養液栽培における培養液の給液には、タイマーや日射比例方式が用いられるが、作目、季節、天候、作物の生育状況等は全く考慮されないため、これらを考慮して、その都度、給液量や給液間隔の設定を修正しなければならない。
このため、栽培期間を通じて、作物に適量の培養液を、完全に自動で給液することは不可能である。また、給液設定の修正には、生産者の長年の経験や高度な技術が必要なため、給液管理に失敗し、生育不良や収量低下を引き起こす危険性がある。
【０００３】
さらに、ロックウール栽培では、病気の発生、拡散や養分組成が乱れることを防ぐために、かけ流し方式をとる場合が多く、このとき安全を見越して、供給量の３０％程度が排液となるように培養液を供給している。
このため、大量の使用済み培養液が施設外へ排出され、資源の無駄と地下水等の環境汚染への原因となっている。
【０００４】
これらの状況を背景として、作物に対して適量の培養液を、生育期間を通じて完全自動で供給することができ、排液削減により養水分の利用効率が高い、養液栽培の給液法が強く望まれている。
【０００５】
病気の発生、拡散や養分組成の乱れなしに排液を出さない方法には、培養液のリサイクル法があるが、貯留タンク、ろ過・殺菌装置など大規模な設備が必要であり、多大なコストがかかる上に、常に収益低下や尻腐れ果など品質低下等の危険を伴っている。さらに、リサイクル設備を用いても、培養液組成が修正できないほど乱れる場合もあり、系外に捨てざるを得ない場合もある。
【０００６】
【発明が解決しようとする課題】
本発明は、上記の課題を解決して、園芸作物の生育遅延や収量低下を招くことなく、園芸作物の生育に応じて自動的に園芸作物にとって適量の培養液を自動給液することのできる自動給液方法と自動給液装置を提供することを目的とするものである。
【０００７】
さらに、本発明は、上記の如き自動給液方法と自動給液装置とを用いて、園芸作物の生育遅延や収量低下を招くことなく、園芸作物の生育に応じて自動的に園芸作物にとって適量の培養液を自動給液し、これにより肥料や水の節約及び使用済み培養液の排出量を削減させて、環境負荷が小さく、しかも養水分の利用効率が高くて、園芸作物を効率よく養液栽培することのできる養液栽培方法と養液栽培装置とを提供することを目的とするものである。
【０００８】
【課題を解決するための手段】
本発明者らは、上記の課題を解決するため鋭意検討を重ねた。その結果、驚くべきことにシシオドシにヒントを得た排液量測定補助具を電子天秤と組合せた排液量測定手段を用いることにより、微少な排液量を連続測定することができ、このようにして測定された微少な排液量と培養液の供給量とから園芸作物の吸水量を連続的に算出し、この吸水量に基づいて給液を行うと、園芸作物に適量な培養液を自動的に給液することができることを見出し、かかる知見に基づいて本発明を完成するに到った。
【０００９】
請求項１に係る本発明は、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段を提供するものである。
【００１０】
請求項２に係る本発明は、養液栽培において培養液を自動給液するにあたり、養液栽培ベッドから排出される培養液について、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段を用いて微少な排液量を連続測定し、この排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液することを特徴とする、養液栽培における自動給液方法を提供するものである。
【００１１】
請求項３に係る本発明は、養液栽培ベッド上で培養液を用いて園芸作物を養液栽培するにあたり、養液栽培ベッドから排出される培養液について、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている 排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段を用いて微少な排液量を連続測定し、この排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液しながら園芸作物を栽培することを特徴とする、養液栽培方法を提供するものである。
【００１２】
請求項４に係る本発明は、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段と、前記排液量測定手段により測定された排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定する給液管理制御手段と、前記給液管理制御手段の決定に基づき培養液を自動給液する給液手段と、を備えることを特徴とする、養液栽培における自動給液装置を提供するものである。
【００１３】
請求項５に係る本発明は、園芸作物を培養液を用いて栽培する養液栽培ベッドと、前記養液栽培ベッドから園芸作物が吸収しなかった培養液を排液として排出する排液口と、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に、前記排液口からの排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に、前記排液口からの排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段と、前記排液量測定手段により測定された排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定する給液管理制御手段と、前記給液管理制御手段の決定に基づき培養液を自動給液する給液手段と、を備えることを特徴とする、養液栽培装置を提供するものである。
【００１４】
【発明の実施の形態】
以下、本発明の実施の形態を示す。
請求項１に係る本発明は、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段である。
【００１５】
また、請求項２に係る本発明は、養液栽培における自動給液方法に関し、養液栽培において培養液を自動給液するにあたり、養液栽培ベッドから排出される培養液について、上記請求項１に係る本発明の排液量測定手段を用いて微少な排液量を連続測定し、この排液量と給液量（培養液の供給量）とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液することを特徴とするものである。
【００１６】
次に、請求項３に係る本発明は、請求項２に係る本発明の自動給液方法を用いた養液栽培方法である。
また、請求項４に係る本発明は、請求項２に係る本発明の自動給液方法を実施するのに好適な自動給液装置に関するものである。
さらに、請求項５に係る本発明は、請求項３に係る本発明の養液栽培方法を実施するのに好適な養液栽培装置に関するものである。
従って、本発明を説明するにあたっては、最も広い範囲を規定している、請求項５に係る本発明の養液栽培装置の１例を示す図面に基づき説明するのが最も分かりやすいため、この請求項５に係る本発明の養液栽培装置の１例を示す図面に基づいて、以下、請求項１〜５に係る本発明について説明することとする。
【００１７】
図１は、請求項５に係る本発明の養液栽培装置の１例を示す説明図である。
図１に示される請求項５に係る本発明の養液栽培装置は、養液栽培ベッド１と、排液口２と、排液量測定手段３と、給液管理制御手段４と、給液手段５と、を備えることを特徴とするものである。
なお、請求項４に係る本発明の養液栽培における自動給液装置は、この請求項５に係る本発明の養液栽培装置から、養液栽培ベッド１と排液口２とを除いた、排液量測定手段３と、給液管理制御手段４と、給液手段５と、を備えることを特徴とするものである。
【００１８】
請求項２〜５に係る本発明においては、いずれも請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いる。
請求項２に係る本発明の自動給液方法においては、養液栽培において培養液を自動給液するにあたり、養液栽培ベッド１の排液口２から排出される培養液について、請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて微少な排液量を連続測定する。養液栽培ベッド１としては、噴霧耕を行うことのできる噴霧栽培ベッドが望ましい。この養液栽培ベッド１の下部には排液口２が設けられている。
【００１９】
微少な排液量の連続測定は、排液量測定手段３を用いることにより行う。この排液量測定手段３は、排液口２の下に備えられている。
【００２０】
請求項２〜５に係る本発明において用いる、請求項１に係る本発明の排液量測定手段（排液量測定手段３）は、基本的に排液量測定補助具（自動吐出器具ということもできる。）３１と電子天秤３２とからなるものである。
この排液量測定補助具３１の１例を図２に示す。
排液量測定補助具３１は、図２に示すように、隔壁６を境として、左右に設けられた２つの函状体７Ａ、７Ｂとからなっている。２つの函状体７Ａ、７Ｂとしては、要するにその内部に排液を貯留できるような構造のものであればよく、図２に示すような略円筒形状に限定されるものではなく、全体を略直方体状としたものなどであってもよい。２つの函状体７Ａ、７Ｂとしては、隔壁６を境として、左右対称に設けておく必要はなく、要するに内部に排液がある程度たまったらバランスが崩れ転倒するようなものであればよい。また、函状体７Ａ、７Ｂのサイズについても特に制限はないが、函状体７Ａ、７Ｂをあわせた全長（全幅）が２５ｃｍ程度、或いはそれ以下となるようなサイズとすることが好ましい。
この２つの函状体７Ａ、７Ｂは、それぞれ上方にそれぞれ排液入口８Ａ、８Ｂを備えている。さらに、この２つの函状体７Ａ、７Ｂは、隔壁６を境として左右対称の位置の側方にそれぞれ排液出口９Ａ、９Ｂを備えている。排液出口９Ａ、９Ｂは、後記するように、左右に揺動した際に、函状体７Ａ、７Ｂの内部に貯留する排液を全て一旦吐出できるものであればよく、その形状は特に制限されるものではない。
【００２１】
このような排液量測定補助具３１が、隔壁６下部を支点として左右に揺動自在となるように、電子天秤３２の計量皿上に取り付けられている。電子天秤３２としては、ＲＳ２３２Ｃ等の電気的出力が可能なものが用いられる。電子天秤３２としては、特に制限はないが、０．１ｇ単位のものが好ましく、特に、０．０１ｇ単位のものが好ましい。
なお、このような排液量測定補助具３１の内部に貯留される排液の量は必ずしも微量である必要はなく、排液量測定補助具３１としては、電子天秤３２がオーバーレンジとならないうちに排液を吐出できるものであればよい。
【００２２】
このような排液量測定補助具３１と電子天秤３２とからなる排液量測定手段３を用いての微少な排液量の測定は、具体的には次のようにして行えばよい。
まず測定開始時には排液量測定補助具３１を左右いずれかの方向に揺動させて排液量測定補助具３１を傾斜させた状態としておく。図１では右側に揺動させて排液量測定補助具３１をいわゆる右下がりに傾斜させたものが示されているので、以下、この状態のものについて説明する。
そして、傾斜させて上がっている側、つまり図１では左側の函状体７Ａに備えられている排液入口８Ａから、函状体７Ａの内部に、排液（つまり養液栽培ベッド１の排液口２から排出される培養液）を引き入れ、その内部に貯留する排液の重みを利用して、隔壁６下部を支点として測定開始時の揺動方向とは反対方向へ、つまり図１では左側へ揺動させて下方へ傾斜させることにより、左側の函状体７Ａに備えられている排液出口９Ａから貯留排液を吐出させる。
次いで、新たに傾斜させて上がっている側、つまり今度は右側の函状体７Ｂに備えられている排液入口８Ｂから、函状体７Ｂの内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、隔壁６下部を支点として直前の揺動方向（つまり左側への揺動）とは反対方向（つまり右側）へ揺動させて下方へ傾斜させることにより、函状体７Ｂに備えられている排液出口９Ｂから貯留排液を吐出させる。排液の貯留に従って、以下、これが順次自動的に繰り返される。
【００２３】
換言すると、排液口２から排出された、吸収されなかった分の培養液（余剰の培養液）は、排液量測定補助具３１を構成する２つの函状体７Ａ、７Ｂの一方、図１では左側の函状体７Ａ、に備えられている排液入口８Ａから、函状体７Ａの内部に貯留（蓄積）され、その重量を電子天秤３２により連続計測し、重量変化より排液量を求める。
このとき液が函状体７Ａの内部に閾量以上になると、その内部に貯留する排液の重みで、排液量測定補助具３１全体は、隔壁６下部を支点として測定開始時の揺動方向とは反対方向へ、つまり図１では左側へ揺動し下方へ傾斜することになり、左側の函状体７Ａに備えられている排液出口９Ａから貯留排液が吐出させられる。
前記したように、排液の貯留に従って、以下、これが順次自動的に繰り返されることから、自動的に貯留排液が順次吐出されることになる。これにより、電子天秤３２がオーバーレンジになることが防止される。排液量計測の分解能は電子天秤３２のそれに等しいことから、例えば１０秒あたり０．０１ｇ（１０ｍｇ／１０ｓｅｃ.）といった極めて微少な排液量の測定も可能である。勿論、測定間隔を短くすれば、さらに細かく計測可能であり、１秒間隔以下でも測定可能である。なお、貯留排液の吐出は、必ずしも一定量である必要はなく、貯留した排液が一度に排出されればよい。
【００２４】
上記したような請求項２〜５に係る本発明において用いる、請求項１に係る本発明の排液量測定手段（排液量測定手段３）によれば、上記吐出が順次自動的に繰り返されることから、自動的に貯留排液が順次吐出されることになる。
その結果、養液栽培ベッド１から排出される、余剰の培養液（排液）について、微少な排液量が精度高く連続的に測定できる。
【００２５】
請求項２に係る本発明においては、このようにして請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて測定された排液量と、給液量（培養液の供給量）とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液することを特徴とする。ここで園芸作物の吸水量の連続的な算出と、算出された吸水量に基づく新たな給液量の決定は、給液管理制御手段４により行われる。
【００２６】
即ち、給液管理制御手段４により、上記のようにして請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて測定された排液量と、給液量（培養液の供給量）とから、園芸作物の吸水量が連続的に算出され、算出された吸水量に基づいて新たな給液量が決定される。給液管理制御手段４は、具体的には、給液を制御しうるコンピュータからなる。この制御コンピュータは、必要に応じて環境計測可能なものが用いられる。
さらに、給液手段５により、このようにして給液管理制御手段４により決定された給液量分の培養液が自動給液される。給液手段５は、基本的には給液管５Ａと給液ノズル５Ｂとからなるものである。
【００２７】
ここで給液された培養液は、作物に吸収されるもの、養液栽培ベッド１内に付着しているもの、排出されるものに分けることができるが、頻繁に給液が行われ、速やかに余剰液が排出される状態では、養液栽培ベッド１内に付着している量はほぼ一定であり、給液量（培養液の供給量）と測定された排液量とから、園芸作物の吸水量が連続的に算出される。給液管理制御手段４（制御コンピュータ）は、算出された吸水量に基づいて、次の新たな給液量（培養液の供給量）、並びに給液間隔を決定し、さらに、給液手段５により、このようにして給液管理制御手段４により決定された給液量分の培養液が所定間隔で自動給液される。
【００２８】
このような給液管理制御手段４（制御コンピュータ）による、吸水量に基づいた給液方法の概略についてのフローチャートを図３に示す。
まず、規定量の培養液を園芸作物の根に噴霧等の手段により給液すると、培養液は園芸作物により吸収され、吸収されなかった培養液は排出される。この排液量を連続的に測定し、給液量から排液量を差し引いたものが、吸水量として算出される。この吸水量に基づいて、次の新たな給液量を算出して、給液を行う。
【００２９】
吸水量に基づいて、次の新たな給液量を算出する方法について説明する。
吸水量は、作物の状態と日射、温度、湿度等の環境要因とによって決定されるが、直前の吸水量は、これらを反映した結果とみなすことができる。
従って、直前の吸水量と同量の給液を行えば、環境要因や作物の状態が大きく変化していない限り、作物に適量な給液を行うことができる。
しかし、作物が直前の吸水量より大量の培養液を欲する場合には、直前の吸水量と同量の給液では、作物に全供給量が吸水されてしまうことになる。この場合には、排液がないため、作物が欲している正しい吸水量を算出することができなくなる。これを防ぐために、直前の吸水量よりも若干多い定量、すなわち、いわゆる不感帯（量）〔デッドゾーン〕を設けて（or 加えて）給液することで、作物にストレスを与えないで給液を行うことができ、かつ排液を削減することが可能である。
【００３０】
また、日射等の環境要因の変化は急激な場合が多い。これに対応するため、いわゆるフィードフォワード制御を採用し、直前までの吸水量と日射、温度、湿度等の環境要因の関係式を回帰等により算出し、次回の吸水量について、上記関係式と環境要因とから推測して給液を行うとよい。これにより、急激な環境変化に対応した上で、精度高く適量を自動給液することが可能となり、排液削減も実現できる。
【００３１】
即ち、養液栽培において培養液を自動給液するにあたり、（１）養液栽培ベッドから排出される培養液について、上記のようにして、微少な排液量を連続測定し、（２）この排液量と給液量とから、園芸作物の吸水量を高精度、連続的に算出し、（３）算出された吸水量と日射、温度、湿度等の環境要因の関係式から、気象条件を変数とする吸水量の推定式を導き出し、（４）この推定式と気象条件により、新たな給液量（潅水量）を決定し、決定された給液量だけ培養液を自動給液することにより、日射、温度、湿度等の環境要因、植物体の大きさ、状態に応じて、高精度の給液（潅水）を完全自動で行うことができる。このため、肥料と水の使用量を削減することができ、排液をほとんど出さないため、環境に優しいものとなっている。
【００３２】
請求項３に係る本発明は、上記した如き請求項２に係る本発明の自動給液方法を用いた養液栽培方法である。
即ち、請求項３に係る本発明は養液栽培方法に関し、養液栽培ベッド上で培養液を用いて園芸作物を養液栽培するにあたり、養液栽培ベッドから排出される培養液について、請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて微少な排液量を連続測定し、この排液量と給液量（培養液の供給量）とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液しながら園芸作物を栽培することを特徴とするものである。
【００３３】
本発明が適用される園芸作物には特に制限がなく、蔬菜、果樹、花卉など任意の作物に適用することができる。特に、キュウリ、トマト等の蔬菜類が好適である。
【００３４】
請求項３に係る本発明においては、養液栽培ベッド上で培養液を用いて園芸作物を養液栽培する。
従って、まず園芸作物を養液栽培ベッド１に定植し、給液管理制御手段４（給液を制御しうるコンピュータ）により、所定量の培養液を給液手段５の給液ノズル５Ｂから、園芸作物の根部に供給する。
供給された培養液は園芸作物に吸収されるが、吸収されなかった分の培養液（余剰の培養液）は、排液口２から排出される。
【００３５】
請求項３に係る本発明は、このような養液栽培において、養液栽培ベッドから排出される培養液について、請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて微少な排液量を連続測定し、この排液量と給液量（培養液の供給量）とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液しながら園芸作物を栽培することを特徴とするものである。
【００３６】
微少な排液量の連続測定は、請求項１に係る本発明の排液量測定手段（排液量測定手段３）を用いて行う。この排液量測定手段は、前記したように基本的に排液量測定補助具３１と電子天秤３２とからなるものである。
また、このような排液量測定手段３を用いての微少な排液量の測定法は、請求項１、２に係る本発明において述べた通りである。
【００３７】
請求項３に係る本発明においては、このようにして連続的に微少な排液量をまず測定する。
次いで、請求項３に係る本発明においては、請求項２に係る本発明において述べたと同様にして、上記のようにして測定された排液量と、給液量（培養液の供給量）とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液する。
簡単に言うと、測定された排液量と給液量（培養液の供給量）とから、給液管理制御手段４によって、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて、次の新たな給液量（培養液の供給量）、並びに給液間隔を決定し、さらに、給液手段５により、このようにして給液管理制御手段４により決定された給液量分の培養液が所定間隔で自動給液される。
【００３８】
さらに、請求項３に係る本発明においては、このようにして決定された給液量だけ培養液を自動給液しながら園芸作物を栽培する。
【００３９】
請求項４に係る本発明の養液栽培における自動給液装置は、上記した如き、排液量測定手段３と、給液管理制御手段４と、給液手段５と、を備えることを特徴とするものであり、また、請求項５に係る本発明の養液栽培装置は、図１に示されるように、養液栽培ベッド１と、排液口２と、排液量測定手段３と、給液管理制御手段４と、給液手段５と、を備えることを特徴とするものである。これら各手段については、既に説明した通りである。
【００４０】
なお、上記したように、給液量（培養液の供給量）と排液量とから吸水量を求めていることから、養液栽培ベッド１においては、余剰液が速やかに排出されなければならない。このために、養液栽培ベッド１内に、防根透水性のシート等を用いて園芸作物の根域を制限し、養液栽培ベッド１の排水性を保持することが望ましい。
【００４１】
以上の如き請求項１に係る本発明の排液量測定手段によれば、養液栽培ベッドから排出される余剰の培養液（排液）について微小な排液量が精度高く連続的に測定できる。
また、請求項２に係る本発明の自動給液方法と請求項４に係る本発明の自動給液装置によれば、園芸作物の生育遅延や収量低下を招くことなく、園芸作物の生育に応じて自動的に園芸作物の適量な培養液を自動給液することができる。
【００４２】
さらに、請求項３に係る本発明の養液栽培方法と請求項５に係る本発明の養液栽培装置によれば、上記の如き自動給液方法と自動給液装置とを用いて、園芸作物の生育遅延や収量低下を招くことなく、園芸作物の生育に応じて自動的に園芸作物の適量な培養液を自動給液し、これにより肥料や水の節約及び使用済み培養液の排出量を削減させて、環境負荷が小さく、しかも養水分の利用効率が高くて、園芸作物を効率よく養液栽培することができる。
【００４３】
【実施例】
次に、本発明を実施例により説明するが、本発明はこれらのみに限定されるものではない。
【００４４】
実施例１
図１、２に示す如き養液栽培装置を用いて、キュウリ（アンコール１０）の養液栽培を行った。培養液としては、園試処方培養液100％濃度液(8 meq L^-1 KNO₃, 8 meq L^-1 Ca(NO₃)₂, 4 meq L^-1 MgSO₄, 4 meq L^-1 NH₄H₂PO₄, 3 ppm Fe, 0.05 ppm Mn, 0.5 ppm B, 0.005 ppm Zn, 0.02 ppm Cu, and 0.01 ppm Mo.)を用いた。
具体的には、内寸法が厚さ８０ｍｍ、幅６００ｍｍ、長さ３４５０ｍｍの養液栽培ベッド１（噴霧栽培ベッド）に、２２個体のキュウリを定植し、養液栽培ベッド１から排出される培養液について、図２に示す如き排液量測定補助具３１（全長約２５cm）と電子天秤３２（ＲＳ２３２Ｃ等の電気的出力が可能なもの）とからなる排液量測定手段３を用いて微少な排液量を連続測定し、この排液量と給液量とから、給液管理制御手段４（制御コンピュータ；環境計測可能なもの）により、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定した。
ここで新たな給液量としては、直前の吸水量に不感量〔６ｇ×噴霧間隔（分）〕を加えた量を１回の培養液噴霧量と設定した。
このようにして決定された給液量だけ、給液手段５から培養液を自動給液しながらキュウリを栽培した。
【００４５】
図４は、このときの給液量、排液量、及びこれらより算出した吸水量の推移を示したグラフである。図４内上部の太線が吸水量、細線が給液量、図４内下部の細線が排液量をそれぞれ示している。
図４から明らかなように、吸水量は日中に向け増加し、その後減少しており、この変化に応じて給液量が増減していることが分かる。一方、排液量は一定範囲の中に留まっており、この間の排液率、即ち、排液量／給液量は８％程度であった。
【００４６】
培養液の給液状態及びキュウリの生育等を、日射比例の給液方式を採った以外は、上記した如き本発明の方法と同じ条件下で栽培を行ったものと比較した。
日射比例の給液方式では、１回の噴霧量を固定し、噴霧間隔を調節することにより、日射が375Ｗ／ｍ^２までは日射に比例して給液量を増加させた。日射が375Ｗ／ｍ^２以上の場合には、５分間隔で給液を行った。１回の噴霧量は、栽培期間中、手動で変更し、定植後２２日目まではベッドあたり168ｍｌ、４２日目までは283ｍｌ、これ以降は425ｍｌとした。キュウリの草丈及び給液量の推移について図５に示す。図５では、太線が、本発明による吸水量に基づく給液を行った場合の給液量を示しており、●がそのときの草丈を示している。また、細線が、比較例たる日射比例による給液を行った場合の給液量を示しており、○がそのときの草丈を示している。
【００４７】
図５から明らかなように、本発明による吸水量に基づく給液を行った場合には、作物（キュウリ）の生育に応じて、自動的に給液量が増加していた。一方、比較対照たる日射比例による給液を行った場合には、生育による給液量の増加はみられなかった。また、この日射比例による給液を行った場合には、初期の作物（キュウリ）が小さい状態でも、本発明による吸水量に基づく給液を行った場合に比べ、給液量は多かった。
【００４８】
また、このときの播種後３６日目におけるキュウリの草丈及び葉数について調べた。結果を第１表に示す。
【００４９】
【表１】
第１表

【００５０】
第１表から明らかなように、吸水量に基づく給液（本発明法）では、日射比例による給液（比較対照）によるものと比べ、草丈が高く、葉数も多かった。これは、吸水量に基づく給液（本発明法）では、生育に応じて給液量が増加したため、作物（キュウリ）がストレスを受けることなく、旺盛に生育できたためと考えられる。
【００５１】
このときの栽培終了時までの１個体あたりの作物（キュウリ）の果実本数と収量とについて、第２表に示す。
【表２】
第２表

【００５２】
第２表から明らかなように、吸水量に基づく給液（本発明法）では、日射比例による給液（比較対照）によるものと比べ、果実本数が多く、収量も多かった。これは、吸水量に基づく給液（本発明法）では、旺盛な生育が果実生産に結び付いたためと考えられる。
【００５３】
実施例２
実施例１において、養液栽培ベッド１（噴霧栽培ベッド）に、２０個体のキュウリを定植したこと、及び直前までの吸水量と日射との１次回帰式から算出した量を１回の培養液噴霧量（新たな給液量）と設定したこと、以外は実施例１と同様にして栽培を行った。
【００５４】
図６は、ある晴天日の３０分毎の吸水量と平均日射との相関を◆で示したものである。図６から明らかなように、吸水量と平均日射には、非常に高い相関がみられ、ｙ＝0.021ｘ＋4.9742という１次回帰式が得られた。
【００５５】
新たな給液量は、前日に算出された上記１次回帰式と設定排液率（排液量／給液量）に基づき、日射の実測値を当てはめて算出した。なお、栽培期間中、１日毎の吸水量と日射との１次回帰の相関関係は、栽培期間全体の平均で0.88と非常に高いものであった。
【００５６】
培養液の給液状態及びキュウリの生育等を、日射比例の給液方式を採った以外は、上記した如き本発明の方法と同じ条件下で栽培を行ったものと比較した。
日射比例の給液方式では、１回の噴霧量を固定し、噴霧間隔を調節することにより、日射が571.2Ｗ／ｍ^２までは日射に比例して給液量を増加させた。日射が571.2Ｗ／ｍ^２以上の場合には、３分間隔で給液を行った。0：00〜翌日0：00までの２４時間における総給液量と総排液量を測定し、排液率（排液量／給液量）が0.3前後となるように１回の噴霧量を変更した。給液量と排液量の推移について図７に示す。
【００５７】
図７では、太線が、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合の給液量を示しており、そのときの排液量を太破線で示している。また、細線が、比較例たる日射比例による給液を行った場合の給液量を示しており、そのときの排液量を細破線で示している。
【００５８】
図７から明らかなように、昼間の給液量については、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合と比較例たる日射比例による給液を行った場合とに大きな差はないが、比較例たる日射比例による給液を行った場合に排液が多かった。
【００５９】
また、このときの播種後３７日目におけるキュウリの草丈及び葉数について調べた。結果を第３表に示す。
【００６０】
【表３】
第３表

【００６１】
第３表から明らかなように、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合には、日射比例による給液（比較対照）によるものと比べ、草丈が高く、葉数も多かった。これは、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合には、生育に応じた給液が行われ、作物（キュウリ）がストレスを受けることなく、旺盛に生育できたためと考えられる。
【００６２】
このときの栽培終了時までの１個体あたりの作物（キュウリ）の果実本数と収量とについて、第４表に示す。
【００６３】
【表４】
第４表

【００６４】
第４表から明らかなように、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合には、日射比例による給液（比較対照）によるものと比べ、果実本数が多く、収量も多かった。これは、吸水量と日射の回帰式に基づく給液（本発明法＋日射の回帰式に基づく給液）を行った場合には、作物の生育や状態により変化する吸水量に応じて給液が行われるため、作物（キュウリ）にストレスを与えることなく、効率的に培養液を供給することができたためと考えられる。
【００６５】
【発明の効果】
請求項１に係る本発明の排液量測定手段によれば、養液栽培ベッドから排出される余剰の培養液（排液）について微小な排液量が精度高く連続的に測定できる。
また、請求項２に係る本発明の養液栽培における自動給液方法及び請求項４に係る本発明の養液栽培における自動給液装置によれば、園芸作物の生育不良や収量低下を伴うことなく、園芸作物の生育に応じて自動的に園芸作物にとって適量の培養液を自動給液することができる。
従って、請求項２に係る本発明の養液栽培における自動給液方法及び請求項４に係る本発明の養液栽培における自動給液装置によれば、不必要な給液を行わないので、肥料や水の節約及び使用済み培養液の排出量を削減させ、環境負荷を小さなものとすることができる。
【００６６】
また、請求項３に係る本発明の養液栽培方法及び請求項５に係る本発明の養液栽培装置によれば、上記の如き自動給液方法と自動給液装置とを用いて、園芸作物の生育遅延や収量低下を招くことなく、園芸作物の生育に応じて自動的に園芸作物にとって適量の培養液を自動給液し、これにより肥料や水の節約及び使用済み培養液の排出量を削減させて、環境負荷が小さく、しかも養水分の利用効率が高くて、園芸作物を効率よく養液栽培することができる。
【図面の簡単な説明】
【図１】 請求項５に係る本発明の養液栽培装置の１例を示す説明図である。
【図２】 排液量測定補助具３１の１例を示す説明図である。
【図３】 給液管理制御手段４（制御コンピュータ）による、吸水量に基づいた給液方法の概略についてのフローチャートである。
【図４】 実施例１において、培養液を自動給液しながらキュウリを栽培したときの給液量、排液量、及びこれらより算出した吸水量の推移を示したグラフである。
【図５】 実施例１において、培養液を自動給液しながらキュウリを栽培したときのキュウリの草丈及び給液量の推移を示したグラフである。
【図６】 実施例２における、ある晴天日の３０分毎の吸水量と平均日射との相関を示したものである。
【図７】 実施例２における給液量と排液量の推移を示したグラフである。
【符号の説明】
１ 養液栽培ベッド
２ 排液口
３ 排液量測定手段
４ 給液管理制御手段
５ 給液手段５
５Ａ 給液管
５Ｂ 給液ノズル
６ 隔壁
７Ａ、７Ｂ 函状体
８Ａ、８Ｂ 排液入口
９Ａ、９Ｂ 排液出口
３１ 排液量測定補助具
３２ 電子天秤[0001]
BACKGROUND OF THE INVENTION
  The present inventionUsing the drainage amount measuring means and the drainage amount measuring meansThe present invention relates to an automatic liquid supply method and an automatic liquid supply device in hydroponics, and a hydroponics method and a hydroponic device using the same. More particularly, the present invention provides:Using the drainage amount measuring means capable of measuring a minute drainage amount accurately and continuously with respect to surplus culture fluid (drainage) discharged from the hydroponic bed, and using the drainage amount measurement means,A method and apparatus capable of automatically supplying an appropriate amount of a culture solution according to the growth of a horticultural crop without causing poor growth of horticultural crops or a decrease in yield, and such an automatic liquid supplying method and automatic liquid supplying apparatus, It is related with the method and apparatus which can carry out the hydroponic cultivation of a horticultural crop efficiently, reducing fertilizer and water saving, and reducing the discharge | emission amount of a used culture solution.
[0002]
[Prior art]
  In the production of horticultural crops such as sugar beet and flowers, the proportion of hydroponic cultivation including rock wool cultivation is increasing. In general, the supply of culture solution in hydroponics uses a timer or proportional proportion of solar radiation, but the crop, season, weather, crop growth, etc. are not taken into account at all. Each time, the setting of the amount of liquid supply and the interval of liquid supply must be corrected.
  For this reason, it is impossible to supply a proper amount of culture solution to a crop completely automatically throughout the cultivation period. In addition, since correction of the liquid supply setting requires many years of experience and advanced techniques of the producer, there is a risk that the liquid supply management will fail, causing poor growth and reduced yield.
[0003]
  Furthermore, in rock wool cultivation, in order to prevent the occurrence of disease, diffusion and nutrient composition, the pouring method is often used. At this time, about 30% of the supply amount is drained in view of safety. The culture solution is supplied.
  For this reason, a large amount of spent culture solution is discharged out of the facility, causing waste of resources and environmental pollution such as groundwater.
[0004]
  Against this backdrop, an appropriate amount of culture solution can be supplied automatically to the crops throughout the growing period, and the nutrient solution supply method is strong, because the use of nutrient water is high by reducing drainage. It is desired.
[0005]
  Although there is a method for recycling the culture solution to prevent drainage without the occurrence of disease, diffusion, or disturbance of nutrient composition, it requires a large amount of equipment such as a storage tank and filtration / sterilization equipment, which is very expensive. In addition, there are always risks such as a decline in profits and a decline in quality such as rot. Furthermore, even if the recycling equipment is used, the composition of the culture solution may be disturbed to the extent that it cannot be corrected, and it may be inevitably discarded outside the system.
[0006]
[Problems to be solved by the invention]
  The present invention solves the above-mentioned problems, and can automatically supply an appropriate amount of a culture solution for a horticultural crop automatically according to the growth of the horticultural crop without causing a delay in the growth of the horticultural crop and a decrease in yield. An object is to provide an automatic liquid supply method and an automatic liquid supply apparatus.
[0007]
  Furthermore, the present invention uses the automatic liquid supply method and the automatic liquid supply apparatus as described above, and automatically causes an appropriate amount for the horticultural crop according to the growth of the horticultural crop without causing a growth delay or a decrease in yield of the horticultural crop. This automatically saves the fertilizer and water and reduces the amount of spent culture broth, reducing the environmental burden and increasing the use efficiency of nourishing water. An object of the present invention is to provide a hydroponic cultivation method and a hydroponic cultivation apparatus that can be hydroponically grown.
[0008]
[Means for Solving the Problems]
  The inventors of the present invention have made extensive studies in order to solve the above problems. As a result, it is possible to continuously measure a minute amount of drainage by using a means for measuring the amount of drainage combined with an electronic balance, which is surprisingly inspired by a drainage amount. The water absorption amount of the horticultural crops is calculated continuously from the minute drainage amount measured in this way and the supply amount of the culture solution, and when the liquid supply is performed based on this water absorption amount, an appropriate amount of the culture solution for the horticultural crops is obtained. The present inventors have found that the liquid can be automatically supplied, and have completed the present invention based on such knowledge.
[0009]
  The present invention according to claim 1Drainage provided with a drainage inlet above each of the two box bodies provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measuring auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measuring auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring aid is tilted, and from the drainage inlet provided on one side of the box on the tilted side, into one of the boxes. Using the weight of the drainage liquid drawn in and storing in the interior, the lower part of the partition wall is swung in the direction opposite to the swinging direction and tilted downward by using the lower part of the partition wall as a fulcrum. The stored drainage is discharged from the drainage outlet provided on one side. Next, the drainage is drawn into the other side of the box from the drainage inlet provided on the other side of the box that is newly inclined and lifted, By utilizing the weight of the liquid, by swinging in the opposite direction to the previous swinging direction with the lower part of the partition wall as a fulcrum and inclining downward, the drainage outlet provided on the other side of the box-shaped body By discharging the stored drainage liquid and sequentially repeating this, the stored drainage liquid can be automatically discharged sequentially, and the drainage volume measuring means for determining the drainage volume from the measured value of the electronic balanceIs to provide.
[0010]
  The present invention according to claim 2 relates to the culture solution discharged from the hydroponics bed when automatically feeding the culture solution in hydroponics.Drainage provided with a drainage inlet above each of the two box bodies provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measuring auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measuring auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring aid is tilted, and from the drainage inlet provided on one side of the box on the tilted side, into one of the boxes. Using the weight of the drainage liquid drawn in and storing in the interior, the lower part of the partition wall is swung in the direction opposite to the swinging direction and tilted downward by using the lower part of the partition wall as a fulcrum. The stored drainage is discharged from the drainage outlet provided on one side. Next, the drainage is drawn into the other side of the box from the drainage inlet provided on the other side of the box that is newly inclined and lifted, By utilizing the weight of the liquid, by swinging in the opposite direction to the previous swinging direction with the lower part of the partition wall as a fulcrum and inclining downward, the drainage outlet provided on the other side of the box-shaped body By discharging the stored drainage liquid and repeating this in sequence, the stored drainage liquid can be automatically discharged sequentially, using the drainage volume measuring means to obtain the drainage volume from the measured value of the electronic balance.Continuously measure the minute amount of drainage, continuously calculate the amount of water absorption of horticultural crops from this amount of drainage and the amount of liquid supply, determine a new amount of liquid supply based on the calculated amount of water absorption, The present invention provides an automatic liquid supply method in hydroponics, wherein the culture liquid is automatically supplied by the determined liquid supply amount.
[0011]
  The present invention according to claim 3 relates to the culture solution discharged from the hydroponics bed when the horticultural crop is hydroponically cultivated using the culture solution on the hydroponic cultivation bed.Drainage provided with a drainage inlet above each of the two box bodies provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measuring auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measuring auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring aid is tilted, and from the drainage inlet provided on one side of the box on the tilted side, into one of the boxes. Using the weight of the drainage liquid drawn in and storing in the interior, the lower part of the partition wall is swung in the direction opposite to the swinging direction and tilted downward by using the lower part of the partition wall as a fulcrum. The stored drainage is discharged from the drainage outlet provided on one side. Is, then, are provided in the other of said box-like body of the side that up by newly inclined From the drainage inlet, drainage is drawn into the other side of the box, and the weight of the drainage stored in the box is used to swing in the direction opposite to the previous swinging direction with the partition wall lower part as a fulcrum. By moving and tilting downward, the stored drainage liquid is discharged from the drainage outlet provided on the other side of the box-like body, and by sequentially repeating this, the stored drainage liquid can be automatically discharged sequentially. Using the drainage volume measuring means to determine the drainage volume from the measured value of the electronic balanceContinuously measure the minute amount of drainage, continuously calculate the amount of water absorption of horticultural crops from this amount of drainage and the amount of liquid supply, determine a new amount of liquid supply based on the calculated amount of water absorption, The present invention provides a hydroponic cultivation method characterized by cultivating a horticultural crop while automatically supplying a culture solution by a determined supply amount.
[0012]
  Claim 4The present invention according to the present invention includes a drainage inlet above each of the two box-like bodies provided on the left and right sides with the partition wall as a boundary, and drains on the sides of the symmetrical position with respect to the partition wall. A drainage volume measurement auxiliary tool with an outlet is mounted on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum. The drainage volume measuring auxiliary tool is tilted in the direction so as to be tilted, and the box-like shape is provided from the drainage inlet provided on one side of the box-like body on the tilted side. By drawing the drainage into one of the body and using the weight of the drainage stored in the inside of the body, swinging in the opposite direction to the swinging direction with the lower part of the partition wall as a fulcrum and tilting downward The drainage outlet provided on one side of the box From the drainage inlet provided on the other side of the box on the side that has been newly inclined, and draws the drainage into the other side of the box, By utilizing the weight of the drainage stored in the interior, the lower part of the partition is swung in the direction opposite to the previous swinging direction with the lower part of the partition wall as a fulcrum, and is tilted downward. The stored drainage can be automatically discharged sequentially by discharging the stored drainage from the drainage outlet and repeating this process sequentially.In this way, the amount of drainage is obtained from the measured value of the electronic balance.The water absorption amount of the horticultural crop is continuously calculated from the drainage amount measurement means and the drainage amount and the supply amount measured by the drainage amount measurement means, and a new supply based on the calculated water absorption amount. An automatic liquid supply apparatus in hydroponic cultivation, comprising: a liquid supply management control means for determining a liquid amount; and a liquid supply means for automatically supplying a culture liquid based on the determination of the liquid supply management control means Is to provide.
[0013]
  Claim 5The present invention relates to a hydroponics bed for cultivating horticultural crops using a culture solution, a drainage port for discharging the culture solution that the horticultural crops did not absorb from the hydroponic cultivation bed, and a partition wall. Measuring the amount of drainage provided with a drainage inlet above each of the two box bodies provided on the left and right sides, and with a drainage outlet on each side of the symmetrical position with the partition wall as a border The auxiliary tool is mounted on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum. At the start of measurement, the drainage volume measuring auxiliary tool is swung in either the left or right direction. The drainage volume measuring auxiliary tool is in an inclined state, and from the drainage inlet provided in one of the box-like bodies on the inclined side, the one inside the box-like body, Drains the drainage from the drainage port and stores it inside Using the weight of the liquid, it is swung in the direction opposite to the rocking direction with the lower part of the partition wall as a fulcrum, and tilted downward to store from the drainage outlet provided on one of the box-like bodies. From the drainage inlet provided on the other side of the box on the side that is newly inclined and discharged, from the drainage port to the other inside of the box Using the weight of the drainage liquid drawn in and storing the drainage, the box body is tilted downward by swinging in a direction opposite to the previous swinging direction with the lower part of the partition wall as a fulcrum. The other side of the drain is discharged from the drainage outlet, and the stored drainage can be automatically and sequentially discharged by sequentially repeating this.In this way, the amount of drainage is obtained from the measured value of the electronic balance.The water absorption amount of the horticultural crop is continuously calculated from the drainage amount measurement means and the drainage amount and the supply amount measured by the drainage amount measurement means, and a new supply based on the calculated water absorption amount. A hydroponic cultivation apparatus comprising: a liquid supply management control means for determining a liquid amount; and a liquid supply means for automatically supplying a culture liquid based on the determination of the liquid supply management control means. It is.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below.
  The present invention according to claim 1Drainage provided with a drainage inlet above each of the two box bodies provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measuring auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measuring auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring aid is tilted, and from the drainage inlet provided on one side of the box on the tilted side, into one of the boxes. Using the weight of the drainage liquid drawn in and storing in the interior, the lower part of the partition wall is swung in the direction opposite to the swinging direction and tilted downward by using the lower part of the partition wall as a fulcrum. The stored drainage is discharged from the drainage outlet provided on one side. Next, the drainage is drawn into the other side of the box from the drainage inlet provided on the other side of the box that is newly inclined and lifted, By utilizing the weight of the liquid, by swinging in the opposite direction to the previous swinging direction with the lower part of the partition wall as a fulcrum and inclining downward, the drainage outlet provided on the other side of the box-shaped body This is a drainage amount measurement means for determining the drainage amount from the measured value of the electronic balance so that the stored drainage fluid is discharged and the stored drainage fluid can be automatically and sequentially discharged by sequentially repeating this.
[0015]
  The present invention according to claim 2Regarding the automatic liquid supply method in hydroponic culture, for automatically supplying the culture liquid in hydroponic culture, about the culture liquid discharged from the hydroponic bed,Using the drainage measuring means of the present invention according to claim 1A small amount of drainage is continuously measured, and the amount of water absorbed by horticultural crops is continuously calculated from this amount of drainage and the amount of fluid supplied (the amount of culture fluid supplied). The liquid supply amount is determined, and the culture solution is automatically supplied by the determined liquid supply amount.
[0016]
  next,Claim 3The present invention according toClaim 2Hydroponic cultivation method using the automatic liquid feeding method of the present inventionIt is.
  Also,Claim 4The present invention according toClaim 2The present invention relates to an automatic liquid supply apparatus suitable for carrying out the automatic liquid supply method of the present invention.
  further,Claim 5The present invention according to the present invention relates to a hydroponic cultivation apparatus suitable for carrying out the hydroponic cultivation method of the present invention according to claim 3.
  Therefore, in describing the present invention, the widest scope is defined,Claim 5Since it is easiest to explain based on the drawings showing an example of the hydroponic cultivation apparatus of the present invention according to this,Claim 5Based on the drawings showing an example of the hydroponic cultivation apparatus of the present invention according to the present invention, hereinafter, claims 1 to5The present invention will be described.
[0017]
  FIG.Claim 5It is explanatory drawing which shows one example of the hydroponic cultivation apparatus of this invention which concerns on.
  As shown in FIG.Claim 5The hydroponic cultivation apparatus according to the present invention comprises the hydroponic cultivation bed 1, the drainage port 2, the drainage amount measuring means 3, the liquid supply management control means 4, and the liquid supply means 5. It is a feature.
  In addition,Claim 4The automatic liquid supply device in the hydroponic cultivation of the present invention according to thisClaim 5From the nourishing liquid cultivation apparatus according to the present invention, the nourishing liquid cultivation bed 1 and the drainage port 2 are removed, and the drainage amount measuring means 3, the liquid supply management control means 4, and the liquid supply means 5 are provided. It is characterized by this.
[0018]
  In the present invention according to claims 2 to 5, the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1 is used.
  Claim 2In the automatic liquid supply method of the present invention according to the present invention, when the culture liquid is automatically supplied in the nutrient culture, the culture liquid discharged from the drainage port 2 of the nutrient culture bed 1Using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1Continuously measure minute liquid discharge. The hydroponics bed 1 is preferably a spray cultivation bed that can perform spray cultivation. A drainage port 2 is provided at the bottom of the hydroponic bed 1.
[0019]
  The continuous measurement of the minute drainage amount is performed by using the drainage amount measuring means 3.The drainage amount measuring means 3 is provided below the drainage port 2.
[0020]
  The drainage amount measuring means of the present invention according to claim 1 (drainage amount measuring means 3) used in the present invention according to claims 2-5.Is basically composed of a drainage amount measurement auxiliary tool (also referred to as an automatic discharge device) 31 and an electronic balance 32.
  An example of the drainage amount measurement aid 31 is shown in FIG.
  As shown in FIG. 2, the drainage amount measurement auxiliary tool 31 is composed of two box-like bodies 7 </ b> A and 7 </ b> B provided on the left and right sides with the partition wall 6 as a boundary. The two box-like bodies 7A and 7B may be of any structure as long as the drainage can be stored therein, and are not limited to the substantially cylindrical shape as shown in FIG. A rectangular parallelepiped may be used. The two box-like bodies 7A and 7B do not need to be symmetrically provided with the partition wall 6 as a boundary. In short, it is sufficient if the drainage is accumulated to some extent and the balance is lost and falls. The size of the box-like bodies 7A and 7B is not particularly limited, but it is preferable that the total length (full width) of the box-like bodies 7A and 7B is about 25 cm or less.
  The two box-like bodies 7A and 7B are respectively provided with drainage inlets 8A and 8B, respectively. Further, the two box-like bodies 7A and 7B are respectively provided with drainage outlets 9A and 9B on the sides of the symmetrical positions with the partition wall 6 as a boundary. As will be described later, the drain outlets 9A and 9B only need to be able to once discharge all the drained liquid stored inside the box-like bodies 7A and 7B when swinging left and right. Is not to be done.
[0021]
  Such a drainage amount measurement auxiliary tool 31 is mounted on the weighing pan of the electronic balance 32 so as to be swingable left and right with the lower part of the partition wall 6 as a fulcrum. As the electronic balance 32, a device capable of electrical output such as RS232C is used. Although there is no restriction | limiting in particular as the electronic balance 32, A thing of a 0.1g unit is preferable, and a thing of 0.01g unit is especially preferable.
  It should be noted that the amount of drainage stored in the drainage amount measurement auxiliary tool 31 is not necessarily a very small amount. As the drainage amount measurement aid 31, the electronic balance 32 is not overranged. Any device can be used as long as it can discharge liquid.
[0022]
  Specifically, the measurement of the minute drainage amount using the drainage amount measuring means 3 including the drainage amount measuring auxiliary tool 31 and the electronic balance 32 may be performed as follows.
  First, at the start of measurement, the drainage amount measurement auxiliary tool 31 is swung in either the left or right direction so that the drainage amount measurement auxiliary tool 31 is inclined. In FIG. 1, the drainage amount measuring aid 31 is swung rightward so as to incline in a so-called lower right direction.
  Then, from the drained inlet 8A provided in the box 7A on the left side in FIG. 1, ie, the left box 7A in FIG. In the direction opposite to the rocking direction at the start of measurement with the lower part of the partition wall 6 as a fulcrum, using the weight of the drained liquid stored in the liquid inlet 2), that is, in FIG. The stored drainage liquid is discharged from the drainage outlet 9A provided in the left box 7A by swinging leftward and tilting downward.
  Next, the drained liquid is drawn into the box 7B from the drain side 8B provided on the newly tilted side, that is, the right box 7B, and is stored in the box 7B. By utilizing the weight of the liquid, the box 6 is tilted downward by swinging in the opposite direction (that is, rightward) from the previous swinging direction (that is, swinging to the left) with the lower part of the partition wall 6 as a fulcrum. The stored drainage liquid is discharged from the drainage outlet 9B provided in 7B. In the following, this is automatically repeated in sequence as the drainage is stored.
[0023]
  In other words, the unabsorbed culture fluid (excess culture fluid) discharged from the drainage port 2 is one of the two box-like bodies 7A and 7B constituting the drainage amount measurement aid 31. In FIG. 1, from the drainage inlet 8A provided in the left box 7A, the inside of the box 7A is stored (accumulated), and its weight is continuously measured by the electronic balance 32. Ask for.
  At this time, if the liquid exceeds the threshold amount inside the box 7A, the drainage amount measuring auxiliary tool 31 as a whole swings at the start of measurement with the lower part of the partition wall 6 as a fulcrum due to the weight of the drainage stored in the box 7A. In the direction opposite to the direction, that is, in FIG. 1, it swings to the left and tilts downward, and the stored drainage liquid is discharged from the drainage outlet 9A provided in the left box 7A.
  As described above, as the drainage is stored, this is automatically repeated in the following, so that the stored drainage is automatically discharged sequentially. This prevents the electronic balance 32 from being overranged. Since the resolution of the drainage amount measurement is equal to that of the electronic balance 32, it is possible to measure an extremely minute drainage amount of, for example, 0.01 g (10 mg / 10 sec.) Per 10 seconds. Of course, if the measurement interval is shortened, it can be measured more finely, and can be measured even at intervals of 1 second or less. The discharge of the stored drainage does not necessarily have to be a constant amount, and the stored drainage may be discharged at a time.
[0024]
  As mentioned aboveThe drainage amount measuring means of the present invention according to claim 1 (drainage amount measuring means 3) used in the present invention according to claims 2-5.According to the above, since the discharge is automatically repeated sequentially, the stored drainage liquid is automatically discharged sequentially.
  As a result, with respect to the surplus culture solution (drainage) discharged from the hydroponic cultivation bed 1, a minute drainage amount can be continuously measured with high accuracy.
[0025]
  Claim 2In the present invention according to this,Using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1From the measured drainage amount and the supply amount (culture solution supply amount), the water absorption amount of the horticultural crop is continuously calculated, and a new supply amount is determined based on the calculated water absorption amount. The culture solution is automatically supplied by the determined supply amount. Here, the continuous calculation of the water absorption amount of the horticultural crop and the determination of a new liquid supply amount based on the calculated water absorption amount are performed by the liquid supply management control means 4.
[0026]
  That is, by the liquid supply management control means 4, as described above.Using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1The water absorption amount of the horticultural crop is continuously calculated from the measured drainage amount and the liquid supply amount (culture solution supply amount), and a new liquid supply amount is determined based on the calculated water absorption amount. . The liquid supply management control means 4 is specifically composed of a computer that can control liquid supply. As this control computer, a computer capable of measuring an environment as required is used.
  Further, the liquid supply means 5 automatically supplies the culture liquid for the liquid supply amount determined by the liquid supply management control means 4 in this way. The liquid supply means 5 basically includes a liquid supply pipe 5A and a liquid supply nozzle 5B.
[0027]
  The culture solution supplied here can be divided into those that are absorbed by the crop, those that are attached to the hydroponics bed 1, and those that are discharged. In the state where the excess liquid is discharged, the amount adhering in the hydroponics bed 1 is almost constant, and the horticultural crop is determined from the amount of liquid supplied (the amount of culture solution supplied) and the amount of drainage measured. The water absorption amount is calculated continuously. The liquid supply management control unit 4 (control computer) determines the next new liquid supply amount (culture solution supply amount) and the liquid supply interval based on the calculated water absorption amount, and further supplies the liquid supply unit 5. Thus, the culture fluid for the amount of the liquid supply determined in this way by the liquid supply management control means 4 is automatically supplied at a predetermined interval.
[0028]
  FIG. 3 shows a flowchart of the outline of the liquid supply method based on the water absorption amount by the liquid supply management control means 4 (control computer).
  First, when a prescribed amount of culture solution is supplied to the roots of the horticultural crops by means such as spraying, the culture solution is absorbed by the horticultural crops, and the unabsorbed culture solution is discharged. The amount of drainage is continuously measured, and the amount obtained by subtracting the amount of drainage from the amount of liquid supply is calculated as the amount of water absorption. Based on this water absorption amount, the next new liquid supply amount is calculated, and liquid supply is performed.
[0029]
  A method for calculating the next new liquid supply amount based on the water absorption amount will be described.
  The amount of water absorption is determined by the state of the crop and environmental factors such as solar radiation, temperature, and humidity, but the amount of water absorption just before can be regarded as a result reflecting these.
  Therefore, if the same amount of water supply as that of the previous water absorption is performed, an appropriate amount of liquid can be supplied to the crop as long as environmental factors and the state of the crop have not changed significantly.
However, when the crop wants a larger amount of culture solution than the immediately preceding water absorption amount, the supply amount of the same amount as the immediately preceding water absorption amount causes the entire supply amount to be absorbed by the crop. In this case, since there is no drainage, it is impossible to calculate the correct water absorption amount desired by the crop. In order to prevent this, a certain amount of water absorption that is slightly higher than the previous water absorption amount, that is, a so-called dead zone (amount) [dead zone] is provided (or in addition) to supply liquid without applying stress to the crop. This can be done and the drainage can be reduced.
[0030]
  Also, changes in environmental factors such as solar radiation are often rapid. To cope with this, so-called feed-forward control is adopted, and the relational expression between the water absorption up to the previous time and the environmental factors such as solar radiation, temperature, humidity, etc. is calculated by regression etc. It is recommended to supply the liquid by inferring from the factors. Thereby, it is possible to automatically supply an appropriate amount with high accuracy while dealing with a sudden environmental change, and it is also possible to reduce drainage.
[0031]
  That is, in the automatic feeding of the culture solution in the hydroponics, (1) continuously measure the minute drainage amount of the culture solution discharged from the hydroponic bed as described above. Calculate the water absorption amount of horticultural crops from the drainage amount and the liquid supply amount with high accuracy and continuously. (3) From the relational expression of the calculated water absorption amount and environmental factors such as solar radiation, temperature and humidity, the weather conditions (4) A new liquid supply amount (irrigation amount) is determined based on this estimation formula and weather conditions, and the culture solution is automatically supplied by the determined liquid supply amount. Thereby, highly accurate liquid supply (irrigation) can be performed fully automatically according to environmental factors, such as solar radiation, temperature, and humidity, the size of a plant body, and a state. For this reason, the amount of fertilizer and water used can be reduced, and since almost no drainage is produced, it is environmentally friendly.
[0032]
  The present invention according to claim 3 is as described above.Claim 2It is the hydroponics method using the automatic liquid feeding method of this invention which concerns on this.
  That is, the present invention according to claim 3 relates to a hydroponic cultivation method, for hydroponic cultivation of a horticultural crop using a culture solution on a hydroponic cultivation bed,Using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1A small amount of drainage is continuously measured, and the amount of water absorbed by horticultural crops is continuously calculated from this amount of drainage and the amount of fluid supplied (the amount of culture fluid supplied). The liquid supply amount is determined, and the horticultural crop is cultivated while automatically supplying the culture solution by the determined liquid supply amount.
[0033]
  The horticultural crops to which the present invention is applied are not particularly limited, and can be applied to any crops such as sugar beet, fruit trees and flower buds. Particularly, side dishes such as cucumber and tomato are suitable.
[0034]
  In this invention which concerns on Claim 3, a horticultural crop is hydroponically cultivated using a culture solution on a hydroponic cultivation bed.
  Accordingly, first, a horticultural crop is planted in the hydroponics bed 1 and a predetermined amount of culture solution is supplied from the supply nozzle 5B of the supply means 5 by the supply management control means 4 (computer capable of controlling the supply). Supply to the root of the crop.
  The supplied culture solution is absorbed by the horticultural crops, but the amount of the culture solution (excess culture solution) that has not been absorbed is discharged from the drain port 2.
[0035]
  The present invention according to claim 3, in such hydroponics, for the culture fluid discharged from the hydroponics bed,Using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1A small amount of drainage is continuously measured, and the amount of water absorbed by horticultural crops is continuously calculated from this amount of drainage and the amount of fluid supplied (the amount of culture fluid supplied). The liquid supply amount is determined, and the horticultural crop is cultivated while automatically supplying the culture solution by the determined liquid supply amount.
[0036]
  The continuous measurement of the minute amount of drainage is performed using the drainage amount measuring means (drainage amount measuring means 3) of the present invention according to claim 1. This drainage amount measuring means basically comprises the drainage amount measuring auxiliary tool 31 and the electronic balance 32 as described above.
  Moreover, the measurement method of the minute drainage amount using such drainage amount measuring means 3 is as follows.Claims 1, 2This is as described in the present invention.
[0037]
  In the present invention according to claim 3, first, a minute amount of drainage is continuously measured in this way.
  Next, in the present invention according to claim 3,Claim 2In the same manner as described in the present invention, the water absorption amount of the horticultural crop is continuously calculated from the drainage amount measured as described above and the supply amount (the supply amount of the culture solution). A new liquid supply amount is determined based on the absorbed water amount, and the culture solution is automatically supplied by the determined liquid supply amount.
  In short, the water absorption amount of the horticultural crops is continuously calculated by the liquid supply management control means 4 from the measured drainage amount and the supply amount (culture solution supply amount), and the calculated water absorption amount Then, the next new liquid supply amount (culture solution supply amount) and the liquid supply interval are determined, and the liquid supply means 5 further determines the supply amount thus determined by the liquid supply management control means 4. The culture solution for the liquid amount is automatically supplied at predetermined intervals.
[0038]
  Furthermore, in the present invention according to claim 3, horticultural crops are cultivated while automatically supplying the culture solution by the amount of supply determined in this way.
[0039]
  Claim 4The automatic liquid supply device in the hydroponic cultivation according to the present invention comprises the drainage amount measuring means 3, the liquid supply management control means 4, and the liquid supply means 5 as described above. Yes, andClaim 5As shown in FIG. 1, the hydroponic cultivation apparatus according to the present invention includes a hydroponic cultivation bed 1, a drainage port 2, a drainage amount measuring unit 3, a liquid supply management control unit 4, and a liquid supply Means 5 is provided. Each of these means is as already described.
[0040]
  In addition, as described above, since the amount of water absorption is obtained from the supply amount (the supply amount of the culture solution) and the drainage amount, the surplus liquid must be discharged quickly in the hydroponic cultivation bed 1. . For this reason, it is desirable to limit the root area of the horticultural crop using a root-proof water-permeable sheet or the like in the hydroponic cultivation bed 1 to maintain the drainage of the hydroponic culture bed 1.
[0041]
  According to the drainage amount measuring means of the present invention according to claim 1 as described above, a minute drainage amount can be continuously measured with high accuracy for the surplus culture fluid (drainage) discharged from the hydroponics bed. .
  Claim 2The automatic liquid supply method of the present invention according toClaim 4According to the automatic liquid supply device of the present invention according to the present invention, it is possible to automatically supply an appropriate amount of a culture solution of a horticultural crop automatically according to the growth of the horticultural crop without causing a delay in the growth of the horticultural crop or a decrease in yield. it can.
[0042]
  further,Claim 3The hydroponics method of the present invention according toClaim 5According to the hydroponic cultivation apparatus of the present invention according to the present invention, by using the automatic liquid feeding method and the automatic liquid feeding apparatus as described above, according to the growth of the horticultural crops without incurring the growth delay or the yield reduction of the horticultural crops. It automatically feeds an appropriate amount of culture solution for horticultural crops, thereby reducing fertilizer and water and reducing the amount of spent culture solution, reducing the environmental burden and increasing the efficiency of using nourishing water. The horticultural crops can be hydroponically cultivated efficiently.
[0043]
【Example】
  EXAMPLES Next, although an Example demonstrates this invention, this invention is not limited only to these.
[0044]
Example 1
  Using the nutrient solution cultivation apparatus as shown in FIGS. 1 and 2, cucumber (encore 10) was subjected to nutrient solution cultivation. As the culture solution, the garden trial formulation culture solution 100% concentration solution (8 meq L^-1 KNO_Three, 8 meq L^-1 Ca (NO_Three)₂, 4 meq L^-1 MgSO_Four, 4 meq L^-1 NH_FourH₂PO_Four3 ppm Fe, 0.05 ppm Mn, 0.5 ppm B, 0.005 ppm Zn, 0.02 ppm Cu, and 0.01 ppm Mo.).
  Specifically, 22 individual cucumbers are planted in the hydroponics bed 1 (spray cultivation bed) having an internal dimension of 80 mm in thickness, 600 mm in width, and 3450 mm in length, and the culture solution discharged from the hydroponics bed 1 2 using a drainage volume measuring means 3 comprising a drainage volume measuring auxiliary tool 31 (total length of about 25 cm) and an electronic balance 32 (one capable of electrical output such as RS232C) as shown in FIG. The liquid amount is continuously measured, and the water absorption amount of the horticultural crop is continuously calculated from the drainage amount and the liquid supply amount by the liquid supply management control means 4 (control computer; capable of measuring the environment). A new liquid supply amount was determined based on the water absorption amount.
  Here, as a new liquid supply amount, an amount obtained by adding a dead amount [6 g × spray interval (minutes)] to the immediately preceding water absorption amount was set as one culture solution spray amount.
  Cucumbers were cultivated while automatically supplying the culture solution from the solution supply means 5 by the amount of supply determined in this way.
[0045]
  FIG. 4 is a graph showing the transition of the liquid supply amount, the drainage amount, and the water absorption amount calculated from these at this time. The thick line at the top in FIG. 4 indicates the amount of water absorption, the thin line indicates the amount of liquid supply, and the thin line at the bottom in FIG. 4 indicates the amount of drainage.
  As is clear from FIG. 4, the water absorption increases toward the daytime and then decreases, and it can be seen that the amount of liquid supply increases and decreases according to this change. On the other hand, the drainage amount remained within a certain range, and the drainage rate during this period, that is, the drainage amount / liquid supply amount was about 8%.
[0046]
  The liquid supply state of the culture liquid and the growth of cucumber were compared with those grown under the same conditions as the method of the present invention as described above, except that a liquid supply system proportional to solar radiation was adopted.
  In the liquid supply method proportional to solar radiation, the amount of solar spray is 375 W / m by fixing the spray amount per time and adjusting the spray interval.²Until then, the liquid supply was increased in proportion to solar radiation. Solar radiation is 375W / m²In the above case, liquid supply was performed at intervals of 5 minutes. The spray amount at one time was changed manually during the cultivation period, and was 168 ml per bed until the 22nd day after planting, 283 ml until the 42nd day, and 425 ml thereafter. FIG. 5 shows changes in plant height and liquid supply amount of cucumber. In FIG. 5, the thick line shows the liquid supply amount when the liquid supply based on the water absorption amount according to the present invention is performed, and ● indicates the plant height at that time. Moreover, the thin line has shown the liquid supply amount at the time of performing the liquid supply by the solar radiation proportion which is a comparative example, and (circle) has shown the plant height at that time.
[0047]
  As is apparent from FIG. 5, when the liquid supply based on the water absorption amount according to the present invention was performed, the liquid supply amount automatically increased according to the growth of the crop (cucumber). On the other hand, when the liquid supply was performed according to the proportion of solar radiation as a comparative control, no increase in the liquid supply amount due to growth was observed. Moreover, when the liquid supply by this solar radiation proportion was performed, even if the initial crop (cucumber) was small, the liquid supply amount was larger than when the liquid supply based on the water absorption amount according to the present invention was performed.
[0048]
  Further, the plant height and the number of leaves of the cucumber on the 36th day after sowing were examined. The results are shown in Table 1.
[0049]
[Table 1]
                        Table 1

[0050]
  As apparent from Table 1, the liquid supply based on the amount of water absorption (the method of the present invention) had a higher plant height and a larger number of leaves than the liquid supply based on solar radiation (comparative control). This is considered to be because in the liquid supply based on the amount of water absorption (the method of the present invention), the liquid supply amount increased according to the growth, so that the crop (cucumber) could grow vigorously without being stressed.
[0051]
  Table 2 shows the number of fruits (cucumber) per crop and yield until the end of cultivation at this time.
[Table 2]
                        Table 2

[0052]
  As is apparent from Table 2, the number of fruits and the yield were higher in the liquid supply based on the amount of water absorption (method of the present invention) than in the liquid supply based on solar radiation (comparative control). This is considered to be because vigorous growth was linked to fruit production in the liquid supply based on the amount of water absorption (method of the present invention).
[0053]
Example 2
  In Example 1, 20 cucumbers were planted in a hydroponic cultivation bed 1 (spray cultivation bed), and the amount calculated from the linear regression equation of water absorption and solar radiation until just before was one culture solution. Cultivation was carried out in the same manner as in Example 1 except that the spray amount (new liquid supply amount) was set.
[0054]
  FIG. 6 shows the correlation between the amount of water absorption every 30 minutes on a sunny day and the average solar radiation with ♦. As is clear from FIG. 6, a very high correlation was observed between the amount of water absorption and the average solar radiation, and a linear regression equation y = 0.021x + 4.9742 was obtained.
[0055]
  The new liquid supply amount was calculated by applying the measured value of solar radiation based on the linear regression equation calculated on the previous day and the set drainage rate (drainage amount / liquid supply amount). In addition, during the cultivation period, the correlation of the linear regression between the amount of water absorption per day and the solar radiation was as high as 0.88 on average in the whole cultivation period.
[0056]
  The liquid supply state of the culture liquid and the growth of cucumber were compared with those grown under the same conditions as the method of the present invention as described above, except that a liquid supply system proportional to solar radiation was adopted.
  In the liquid supply system proportional to solar radiation, the solar radiation is 571.2 W / m by fixing the spray amount per one time and adjusting the spray interval.²Until then, the liquid supply was increased in proportion to solar radiation. Solar radiation is 571.2W / m²In the above case, liquid supply was performed at intervals of 3 minutes. Measure the total liquid supply amount and total liquid discharge amount for 24 hours from 0:00 to 0:00 on the next day, and the amount of spray per time so that the liquid discharge rate (drainage amount / liquid supply amount) is about 0.3 Changed. Changes in the amount of supplied liquid and the amount of discharged liquid are shown in FIG.
[0057]
  In FIG. 7, the thick line indicates the amount of liquid supplied when the liquid supply based on the regression equation of water absorption and solar radiation (liquid supply based on the method of the present invention + the solar radiation regression) is performed, and the drainage at that time The amount is indicated by a thick broken line. Moreover, the thin line has shown the liquid supply amount at the time of performing the liquid supply by the solar radiation proportionality which is a comparative example, and the drainage amount at that time is shown by the thin broken line.
[0058]
  As is clear from FIG. 7, the amount of water supply during the daytime is the same as the case where the liquid supply based on the regression equation of the water absorption amount and the solar radiation (the method of the present invention + the liquid supply based on the regression equation of solar radiation) and the solar radiation as a comparative example. Although there was no significant difference from the case where the proportional liquid supply was performed, there was a lot of drainage when the liquid supply was performed according to the solar radiation proportional example.
[0059]
  Further, the plant height and the number of leaves of cucumbers on the 37th day after sowing were examined. The results are shown in Table 3.
[0060]
[Table 3]
                          Table 3

[0061]
  As is apparent from Table 3, when a liquid supply based on a regression equation of water absorption and solar radiation (a liquid supply based on the present invention method + a solar radiation regression equation) was performed, a liquid supply based on the proportion of solar radiation (comparison control) The plant height was higher and the number of leaves was higher than that of This is because when a liquid supply based on a regression equation of water absorption and solar radiation (a liquid supply based on the method of the present invention + a solar radiation regression formula) is performed, a liquid supply according to the growth is performed and the crop (cucumber) is It is thought that it was able to grow vigorously without being stressed.
[0062]
  Table 4 shows the number and yield of fruits (cucumber) per plant until the end of cultivation at this time.
[0063]
[Table 4]
                          Table 4

[0064]
  As is clear from Table 4, when liquid supply based on the regression formula of water absorption and solar radiation (liquid supply based on the present invention method + solar radiation regression formula) was performed, the liquid supply was proportional to solar radiation (comparison control). The number of fruits was higher and the yield was higher than that of This is because when water supply based on the regression equation of water absorption and solar radiation (liquid supply based on the method of the present invention + solar radiation regression) is performed, the liquid supply depends on the amount of water absorption that changes depending on the growth and state of the crop. This is considered to be because the culture solution could be supplied efficiently without giving stress to the crop (cucumber).
[0065]
【The invention's effect】
  According to the drainage amount measuring means of the present invention according to claim 1, a minute drainage amount can be continuously measured with high accuracy for the surplus culture solution (drainage) discharged from the nutrient solution cultivation bed.
  Claim 2An automatic liquid supply method in hydroponics of the present invention according to the present invention andClaim 4According to the automatic liquid supply device for hydroponics of the present invention according to the present invention, an appropriate amount of the culture solution is automatically supplied to the horticultural crops automatically in accordance with the growth of the horticultural crops without being accompanied by poor growth of the horticultural crops or a decrease in yield. Can be liquid.
  Therefore,Claim 2An automatic liquid supply method in hydroponics of the present invention according to the present invention andClaim 4According to the automatic liquid supply apparatus in the hydroponic cultivation of the present invention, since unnecessary liquid supply is not performed, fertilizer and water saving and the discharge amount of used culture liquid are reduced, and the environmental load is reduced. can do.
[0066]
  Also,Claim 3The hydroponics method of the present invention according toClaim 5According to the hydroponic cultivation apparatus of the present invention according to the present invention, by using the automatic liquid feeding method and the automatic liquid feeding apparatus as described above, according to the growth of the horticultural crops without incurring the growth delay or the yield reduction of the horticultural crops. It automatically feeds the appropriate amount of culture solution for horticultural crops, thereby reducing fertilizer and water consumption and reducing the amount of used culture solution discharged. The horticultural crops can be hydroponically cultivated efficiently.
[Brief description of the drawings]
[Figure 1]Claim 5It is explanatory drawing which shows one example of the hydroponic cultivation apparatus of this invention which concerns on.
FIG. 2 is an explanatory view showing an example of a drainage amount measurement auxiliary tool 31. FIG.
FIG. 3 is a flowchart of an outline of a liquid supply method based on a water absorption amount by a liquid supply management control means 4 (control computer).
FIG. 4 is a graph showing changes in the amount of liquid supply, the amount of drainage, and the amount of water absorption calculated from these when cucumber was grown while automatically supplying the culture solution in Example 1.
FIG. 5 is a graph showing changes in plant height and liquid supply amount of cucumber when cultivating cucumber while automatically supplying culture liquid in Example 1.
6 shows the correlation between the amount of water absorption every 30 minutes on a sunny day and average solar radiation in Example 2. FIG.
FIG. 7 is a graph showing changes in the amount of liquid supply and the amount of drainage in Example 2.
[Explanation of symbols]
  1 Hydroponic bed
  2 Drainage port
  3 Drainage measurement means
  4 Liquid supply management control means
  5 Liquid supply means 5
  5A supply pipe
  5B Liquid supply nozzle
  6 Bulkhead
  7A, 7B Box
  8A, 8B Drainage inlet
  9A, 9B Drain outlet
  31 Drainage volume measurement aid
  32 Electronic balance

Claims (5)

隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段。Drainage provided with a drainage inlet above each of the two boxes provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measurement auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measurement auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring auxiliary tool is tilted, and from the drainage inlet provided in one of the box-like bodies on the tilted side, into one of the box-like bodies. Using the weight of the drained liquid drawn in and storing the drainage in the interior, the lower part of the partition wall is used as a fulcrum to swing in the opposite direction to the swinging direction and tilt downward. The stored drainage is discharged from the drainage outlet provided on one side. Next, drainage is drawn into the other side of the box from the drainage inlet provided on the other side of the box that is newly inclined and raised, and the drainage stored in the inside is drained. By utilizing the weight of the liquid, the lower part of the partition wall is used as a fulcrum to swing in the direction opposite to the previous swinging direction and tilted downward. A drainage amount measuring means for determining the drainage amount from the measured value of the electronic balance so that the stored drainage fluid is discharged and the stored drainage fluid can be automatically and sequentially discharged by sequentially repeating this. 養液栽培において培養液を自動給液するにあたり、養液栽培ベッドから排出される培養液について、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段を用いて微少な排液量を連続測定し、この排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液することを特徴とする、養液栽培における自動給液方法。When automatically supplying the culture solution in hydroponics, the culture solution drained from the hydroponic bed is equipped with a drainage inlet above each of the two boxes on the left and right sides of the partition wall. And a drainage volume measuring auxiliary tool provided with a drainage outlet on each side of a symmetrical position with the partition wall as a boundary, and an electronic balance of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum. Attach the drainage volume measurement auxiliary tool to either the left or right direction at the beginning of measurement, and place the drainage volume measurement auxiliary tool in a tilted state. From the drainage inlet provided in one of the box-shaped bodies, the drainage is drawn into one of the box-shaped bodies, and the weight of the drainage stored in the inside of the box-shaped body is used as a fulcrum at the lower part of the partition wall. Swing in the direction opposite to the swing direction By letting it tilt downward, the stored drainage liquid is discharged from the drainage outlet provided on one side of the box, and then the other side of the box on the side that is newly tilted up With the drainage inlet provided, the drainage is drawn into the other inside of the box, and the weight of the drainage stored in the inside of the box is used to determine the previous swinging direction with the partition wall lower part as a fulcrum. By swinging in the opposite direction and inclining downward, the stored drainage liquid is discharged from the drainage outlet provided on the other side of the box-like body, and by repeating this in sequence, the stored drainage liquid is automatically discharged. A small amount of drainage is continuously measured using a drainage volume measuring means that calculates the drainage volume from the measured value of the electronic balance so that it can be discharged sequentially. The water absorption amount is calculated continuously, and a new water absorption amount is calculated based on the calculated water absorption amount. Determining a liquid volume, characterized by automatically feeding liquid the determined liquid supply amount by the culture liquid, the method automatically feeding liquid in hydroponics. 養液栽培ベッド上で培養液を用いて園芸作物を養液栽培するにあたり、養液栽培ベッドから排出される培養液について、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用し て、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段を用いて微少な排液量を連続測定し、この排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定し、決定された給液量だけ培養液を自動給液しながら園芸作物を栽培することを特徴とする、養液栽培方法。When hydroponically cultivating horticultural crops using a culture solution on a hydroponic bed, the culture solution discharged from the hydroponic bed is located above each of the two boxes provided on the left and right sides of the partition wall. Each having a drainage inlet, and a drainage volume measuring auxiliary tool having a drainage outlet on each side of a symmetrical position with respect to the partition wall, and swingable to the left and right with the lower part of the partition wall as a fulcrum. So that it is mounted on the weighing pan of the electronic balance, and at the start of measurement, the drainage volume measurement auxiliary tool is swung in either the left or right direction so that the drainage volume measurement auxiliary tool is tilted. From the drainage inlet provided on one side of the box on the side that is raised, drainage is drawn into one of the boxes, and the weight of drainage stored in the box is used. The swinging direction with the lower part of the partition wall as a fulcrum Is swung in the opposite direction and tilted downward so that the stored drainage liquid is discharged from the drainage outlet provided on one side of the box-like body, and then the side on the newly tilted side is raised. From the drainage inlet provided on the other side of the box, drainage is drawn into the other side of the box, and the weight of the drainage stored in the inside of the box is used, and the lower part of the partition is used as a fulcrum. Is swung in a direction opposite to the swinging direction of the liquid and tilted downward, so that the stored drainage is discharged from the drainage outlet provided on the other side of the box-like body, and this is sequentially repeated to automatically Therefore, it is possible to sequentially discharge the stored drainage liquid, and continuously measure the minute drainage volume using the drainage volume measuring means to obtain the drainage volume from the measured value of the electronic balance. The water absorption amount of horticultural crops is continuously calculated from Characterized by cultivating horticultural crops while automatically Dispense new liquid supply amount is determined and determined the liquid supply amount by the culture medium on the basis of, hydroponics method. 隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段と、前記排液量測定手段により測定された排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定する給液管理制御手段と、前記給液管理制御手段の決定に基づき培養液を自動給液する給液手段と、を備えることを特徴とする、養液栽培における自動給液装置。Drainage provided with a drainage inlet above each of the two box bodies provided on the left and right with the partition wall as a boundary, and with a drainage outlet on each side of the symmetrical position with the partition wall as a boundary. Mount the volume measuring auxiliary tool on the weighing pan of the electronic balance so that it can swing left and right with the lower part of the partition wall as a fulcrum, and swing the drainage volume measuring auxiliary tool in either the left or right direction at the start of measurement. The drainage volume measuring aid is tilted, and from the drainage inlet provided on one side of the box on the tilted side, into one of the boxes. Using the weight of the drainage liquid drawn in and storing in the interior, the lower part of the partition wall is swung in the direction opposite to the swinging direction and tilted downward by using the lower part of the partition wall as a fulcrum. The stored drainage is discharged from the drainage outlet provided on one side. Next, the drainage is drawn into the other side of the box from the drainage inlet provided on the other side of the box that is newly inclined and lifted, By utilizing the weight of the liquid, by swinging in the opposite direction to the previous swinging direction with the lower part of the partition wall as a fulcrum and inclining downward, the drainage outlet provided on the other side of the box-shaped body By discharging the stored drainage liquid and sequentially repeating this, the stored drainage liquid can be automatically discharged sequentially , and the drainage volume measuring means for obtaining the drainage volume from the measured value of the electronic balance, and the drainage volume A liquid supply management control means for continuously calculating the water absorption amount of the horticultural crop from the drainage amount and the liquid supply amount measured by the measurement means, and determining a new liquid supply amount based on the calculated water absorption amount; And automatically supplying the culture liquid based on the determination of the liquid supply management control means Characterized in that it comprises a liquid means, the automatic liquid supply device in hydroponics. 園芸作物を培養液を用いて栽培する養液栽培ベッドと、前記養液栽培ベッドから園芸作物が吸収しなかった培養液を排液として排出する排液口と、隔壁を境として、左右に設けられた２つの函状体のそれぞれ上方にそれぞれ排液入口を備え、かつ、前記隔壁を境として左右対称の位置の側方にそれぞれ排液出口を備えた排液量測定補助具を、前記隔壁下部を支点として左右に揺動自在となるように、電子天秤の計量皿上に取り付け、測定開始時には前記排液量測定補助具を左右いずれかの方向に揺動させて前記排液量測定補助具を傾斜させた状態としておき、傾斜させて上がっている側の前記函状体の一方に備えられている排液入口から、前記函状体の一方の内部に、前記排液口からの排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として前記揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の一方に備えられている排液出口から貯留排液を吐出させ、次いで、新たに傾斜させて上がっている側の前記函状体の他方に備えられている排液入口から、前記函状体の他方の内部に、前記排液口からの排液を引き入れ、その内部に貯留する排液の重みを利用して、前記隔壁下部を支点として直前の揺動方向とは反対方向へ揺動させて下方へ傾斜させることにより、前記函状体の他方に備えられている排液出口から貯留排液を吐出させ、これを順次繰り返すことにより、自動的に貯留排液を順次吐出できるようにして、電子天秤の測定値から排液量を求める排液量測定手段と、前記排液量測定手段により測定された排液量と給液量とから、園芸作物の吸水量を連続的に算出し、算出された吸水量に基づいて新たな給液量を決定する給液管理制御手段と、前記給液管理制御手段の決定に基づき培養液を自動給液する給液手段と、を備えることを特徴とする、養液栽培装置。A hydroponics bed for cultivating horticultural crops using a culture solution, a drainage port for discharging the culture solution not absorbed by the horticultural crops from the hydroponic cultivation bed, and a left and right side with a partition wall as a boundary A drainage volume measuring auxiliary tool provided with a drainage inlet above each of the two box-shaped bodies, and having a drainage outlet at each side of a symmetrical position with respect to the partition wall, Mounted on the weighing pan of the electronic balance so that it can swing left and right with the lower part as a fulcrum. At the start of measurement, swing the drainage volume measuring aid in either the left or right direction to assist the drainage volume measurement. The device is kept in an inclined state, and from the drainage inlet provided in one of the box-like bodies on the inclined side, the drainage from the drainage port is introduced into one of the box-like bodies. Uses the weight of the drained liquid that is drawn in and stored inside Then, with the lower part of the partition wall as a fulcrum, the stored drainage liquid is discharged from the drainage outlet provided on one side of the box-like body by swinging in the direction opposite to the swinging direction and tilting downward. Next, from the drainage inlet provided on the other side of the box that is newly inclined, the drainage from the drainage port is drawn into the other side of the box, Using the weight of the drainage stored in the interior, the lower part of the partition is swung in the direction opposite to the previous swinging direction with the lower part of the partition wall as a fulcrum, and is tilted downward. A drainage volume measuring means for determining the drainage volume from the measured value of the electronic balance so that the stored drainage liquid can be automatically discharged sequentially by discharging the stored drainage liquid from the drainage outlet , The drainage amount measured by the drainage amount measuring means and the supply amount The water absorption amount of the horticultural crop is continuously calculated from the amount, and the liquid supply management control means for determining a new liquid supply amount based on the calculated water absorption amount, and the culture based on the determination of the liquid supply management control means A hydroponic cultivation apparatus comprising: a liquid supply means for automatically supplying liquid.

Images