JPH0347807B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is directed to culture medium management in a system for cultivating plants for food, ornamental use, etc. in a medium such as soil, sand, peat moss, rock wool, etc. It is about the method.

(Prior Art) In a system for cultivating plants by using a culture medium and supplying a culture solution such as water or an aqueous fertilizer solution, management of the culture solution of the culture medium is important. However, in the past, there was no suitable detection method that could directly detect the amount of culture solution in the culture medium, so the amount of culture solution supplied was calculated using an indirect method, and the amount increased by 30 to 50 times this value. management. In other words, the amount of water required by plants varies greatly depending on conditions such as the amount of sunlight, temperature, humidity, number of growing days, etc., so the amount of culture solution supplied should be calculated taking these factors into account, and the amount of water needed by plants should be 1.3 to 1.5 times this value. It supplies quantity.

(Problem to be Solved by the Invention) When implementing the above method, if the above-mentioned conditions are constantly monitored and calculations are made to calculate the supply amount, expensive solar radiation sensors, humidity sensors, temperature sensors, etc. are required. Not only are sensors required, but
Complex calculation software is also required, and even if such software is used, it is extremely difficult to perform calculations that satisfy all conditions, and it is not possible to completely prevent water shortages and water excesses. There is also a method that uses a timer that supplies electricity for a certain amount of time at a certain time of the day, without using sensors that automatically monitor the above conditions. Based on the calculated estimated amount, as mentioned above, 1.3 to 1.5 times the maximum required amount is supplied, so on rainy days, for example, there will be an excess supply, resulting in too much water for plant growth. Otherwise, the culture solution may be wasted.

The purpose of the present invention is to solve the above-mentioned conventional problems, namely, to enable direct detection of the amount of culture solution in the culture medium without being affected by fluctuations in temperature or PH of the culture solution. The purpose of this invention is to enable good control of the amount of culture solution in the culture medium by controlling the supply of culture solution based on the amount of culture solution added.

(Means for Solving the Problems) Means for solving the above-mentioned problems will be explained with reference to the drawings corresponding to the examples. First, the culture solution management method of the first invention uses the medium 2, Alternatively, in a system for cultivating plants 6 by supplying a culture solution such as an aqueous fertilizer solution, a pair of electrodes 7 and 8 made of different metals are attached to the medium 2, and the culture solution and the like form a chemical battery. A detection unit 9 for detecting the electromotive force between the electrodes 7 and 8 is provided, and a temperature sensor S1 for detecting the temperature of the culture solution in the medium 2 is provided at an appropriate location. At the same time, the temperature sensor S1 detects the temperature of the culture solution, and based on the relationship between the temperature of the culture solution and the electromotive force, the electromotive force between the electrodes 7 and 8 detected by the detection unit 9 increases. The gist of this method is to detect the amount of culture solution in the medium 2 by correcting the corresponding amount, and to control the supply of the culture solution based on the detected amount of culture solution.

Further, the culture solution management method of the second invention is based on the culture medium 2.
In a system for cultivating plants 6 by supplying water or a culture solution such as an aqueous fertilizer solution, the medium 2
A chemical cell is constructed by attaching a pair of electrodes 7 and 8 made of dissimilar metals to a culture medium, and providing a detection section 9 for detecting the electromotive force between the electrodes 7 and 8. A PH sensor S2 for detecting the PH of
2 detects the pH of the culture solution, and based on the correspondence between the pH of the culture solution and the electromotive force, corrects the amount corresponding to the electromotive force between the electrodes 7 and 8 detected by the detection unit 9, and The gist of this method is to detect the amount of culture solution in the container and control the supply of the culture solution based on the detected amount of culture solution.

(Function) When the pair of electrodes 7 and 8 made of different metals are attached to the medium 2, a battery is constructed using the culture solution in the medium 2 as an electrolyte, and an electromotive force is generated between the electrodes 7 and 8. . When the amount of culture solution in the medium 2 is changed in this state, the electromotive force changes as shown in FIG. 2 with respect to the amount of culture solution. When this is illustrated with respect to the passage of time during plant cultivation, the electromotive force decreases as the amount of culture solution decreases with the passage of time, as shown in FIG. The decrease in electromotive force with respect to the amount of culture solution is due to the fact that the culture medium 2 is not physically continuous and has gaps, so as the amount of culture solution decreases, electrical connection gradually becomes impossible to maintain. In this way, the electromotive force changes in accordance with the change in the amount of culture solution in the medium 2, so the level of the electromotive force is detected by the detection unit 9, and the electromotive force and the amount of culture solution obtained by prior measurement etc. From the correspondence relationship, the amount of culture solution can be detected by the electromotive force detected by the detection unit 9. However, the electromotive force generated between the electrodes 7 and 8 is not limited to the amount of culture solution in the culture medium 2, for example. As shown in Figure 4 a, b, and c, the temperature, pH, and fertilizer concentration of the culture solution change, so simply detecting the electromotive force with the detection unit 9 does not necessarily accurately detect the amount of culture solution. It doesn't necessarily mean you'll get it.

However, among the properties of the above culture solution, changes in electromotive force due to changes in fertilizer concentration are small and can be ignored, and the correspondence between the temperature or PH of the above culture solution and electromotive force can be obtained by prior measurement. I can do it.

Therefore, the detection unit 9 detects an amount corresponding to the electromotive force between the electrodes 7 and 8, and the temperature sensor S1 or PH sensor S2 detects the temperature or PH of the culture solution.
If the amount corresponding to the electromotive force between the electrodes 7 and 8 detected by the detection unit 9 is corrected based on the correspondence between the temperature of the culture solution or PH and the electromotive force, the temperature of these culture solutions can be adjusted. Or the amount of culture solution in the medium 2 can be detected without being affected by changes in PH,
In this way, the supply of the culture solution can be appropriately controlled based on the detected amount of culture solution.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a system explanatory diagram corresponding to an embodiment of the present invention, in which reference numeral 1 indicates a plant cultivation container and 2 indicates a culture medium. The medium 2 may be soil, sand, peat moss, rock wool, etc. as appropriate. Reference numeral 3 indicates a culture solution tank for water or fertilizer aqueous solution, 4 indicates a culture solution supply device such as a pump or a solenoid valve, and 5 indicates a culture solution supply section. The culture solution supply section 5 can be configured to supply the culture solution in the vicinity of the plants 6 in a drip manner, or any other suitable supply method can be applied.

In the above configuration, a chemical battery is constructed by attaching to the medium 2 a pair of electrodes 7 and 8 made of dissimilar metals such as copper and zinc, which can constitute, for example, a Voltaic battery, and the culture solution. This pair of electrodes 7 and 8 are connected to the detection section 9
The electromotive force generated between the electrodes 7 and 8 is detected by the detection section 9.

Next, reference numeral S1 denotes a temperature sensor for the culture solution, which is installed in the culture medium 2 and is configured to directly detect the temperature of the culture solution in the culture medium 2. Also, the code S
2 is the pH sensor of the culture solution, this is the culture solution tank 3
The PH of the culture solution in the medium 2 is indirectly detected by the culture solution provided therein and supplied to the culture medium 2. These sensors S1 and S2 may be installed when there is a possibility that the detectable properties of the culture fluid may vary, and either one or both can be installed.

Reference numeral 10 denotes a control unit, and the control unit 10 includes storage means for storing the correspondence between the electromotive force detected by the detection unit 9 and the amount of culture solution, and the correspondence between the temperature or PH of the culture solution and the electromotive force, and a culture medium. calculation means for correcting the amount corresponding to the electromotive force between the electrodes 7 and 8 detected by the detection unit 9 based on the correspondence between the temperature or PH of the liquid and the electromotive force; This constitutes a means for controlling the culture solution supply device based on the culture solution supply device. As the storage means, any suitable means for storing each correspondence relationship as a function formula or a table can be applied.

With the above configuration, the detection unit 9 detects an amount corresponding to the electromotive force between the electrodes 7 and 8, and the temperature sensor S1 or PH sensor S2 detects the temperature or PH of the culture solution. If the amount corresponding to the electromotive force between the electrodes 7 and 8 detected by the detection unit 9 is corrected based on the correspondence between PH and electromotive force, it will not be affected by changes in the temperature or PH of the culture solution. The amount of culture solution in the medium 2 can be detected, and the supply of the culture solution can be appropriately controlled based on the detected amount of culture solution. The above-mentioned culture solution amount can be derived as an absolute value, or can be controlled without deriving an absolute value.

A method for supplying a culture solution based on the amount of culture solution detected as described above includes, for example, activating the culture solution supply device 4 to start supplying the culture solution when the amount of culture solution decreases to a predetermined value. The amount of culture solution in the culture medium 2 increases due to the supply, and when it reaches a predetermined value, the operation of the culture solution supply device 4 is stopped, and the amount of culture solution in the culture medium 2 is kept within a certain range. How to control the culture solution supply device 4 as well as
After activating, a predetermined amount of culture solution is supplied using a timer, flow meter, etc., and the lower limit of the amount of culture solution is controlled based on the electromotive force mentioned above, but the upper limit is controlled by the timer, etc. , an appropriate method can be applied, and the range of the amount of culture solution to be controlled and the range of electromotive force can be adjusted as appropriate depending on various conditions such as the type of medium 2, the type of plant 6, the number of growing days, and the season. Can be set. For example, under such various conditions, the plants 6 may be successfully cultivated with the amount of culture solution corresponding to the rapidly changing portion of the electromotive force curve shown in FIGS. 2 and 3.
In this case, highly sensitive control can be performed.

Note that the control section 10 that performs the above-mentioned control may have any specific configuration, such as a device using a microcomputer or the like.

The present invention described above is based on attaching a pair of electrodes 7, 8 to the electrically integrated culture medium 2 via a culture solution, but it is possible to attach a plurality of pairs of electrodes 7, 8 to the culture medium 2, which is electrically integrated with the culture medium. It is also possible to make it possible to detect the amount of culture solution for each of the electrodes 7 and 8. However, even if multiple pairs of electrodes 7 and 8 are simply attached to the electrically integrated culture medium 2, they will interfere with each other, so to prevent this interference, each electrode 7 is attached to the detection unit 9. , 8 pairs, it is necessary to configure an input section 11 such as an isolated amplifier that makes the electrodes 7 and 8 pairs independent in AC and DC. By attaching multiple pairs of electrodes 7 and 8 in this way, it is possible to detect the average amount of culture solution in the medium 2 over a wide range, and it is also possible to detect the amount of culture solution for each plant. This has advantages such as being able to perform fine-grained moisture management.
Incidentally, when a plurality of pairs of electrodes 7 and 8 are attached in this way, the method of supplying the culture solution is arbitrary, and it is possible to provide a plurality of culture solution supply devices 4 for the electrically integrated culture medium 2. can. In addition, all of the plurality of mediums 2 that are not electrically integrated, or the medium 2 as appropriate
, one pair or multiple pairs of electrodes 7 and 8 are provided.
It is also possible to control these in an integrated manner by attaching the following, and the specific control method is appropriate.

(Effects of the Invention) Since the present invention is as described above, the conventional control method, that is, estimation of the amount of culture solution supplied in consideration of various conditions without directly detecting the amount of culture solution in the culture medium. Compared to methods that control based on values, the supply of culture solution to the culture medium can be appropriately controlled according to the plant cultivation conditions without being affected by fluctuations in the temperature or PH of the culture solution, Therefore, it is possible to prevent the culture solution in the medium from becoming too much or too little, so that plant cultivation conditions can always be maintained appropriately, and waste of the culture solution can be minimized. effective. In addition, although the present invention can perform such appropriate control, the configuration can be simplified in terms of both hardware and software, and an inexpensive and efficient plant cultivation system can be constructed. There is an effect.

[Brief explanation of drawings]

Fig. 1 is a system explanatory diagram showing an example of a plant cultivation system to which the present invention is applied, Fig. 2 is an explanatory diagram showing the relationship between the amount of culture solution and electromotive force, and Fig. 3 is an explanatory diagram showing the relationship between the amount of culture solution and electromotive force. Figures 4a, b, and c are explanatory diagrams showing the relationship between electromotive force and the temperature, pH, and fertilizer concentration of the culture solution, respectively.
The figure is a system explanatory diagram showing the configuration of an embodiment equipped with a plurality of electrode pairs. Code 1... Plant cultivation container, 2... Medium, 3...
Culture solution tank, 4... Culture solution supply device, 5... Culture solution supply unit, 6... Plant, 7, 8... Electrode, 9...
...Detection section, 10...Control section, 11...Input section.

Claims (1)

[Scope of Claims] 1. In a system for cultivating plants by using a culture medium and supplying a culture solution such as water or an aqueous fertilizer solution, a pair of electrodes made of dissimilar metals is attached to the medium and the culture solution is used to grow plants. A chemical cell is configured, and a detection part is provided to detect the electromotive force between the electrodes, and a temperature sensor is provided at an appropriate location to detect the temperature of the culture solution in the medium, and the detection part responds to the electromotive force between the electrodes. At the same time, the temperature of the culture solution is detected by the temperature sensor, and the amount corresponding to the electromotive force between the electrodes detected by the detection unit is corrected based on the correspondence between the culture solution temperature and the electromotive force. A method for managing a culture medium in a plant cultivation system, which comprises detecting the amount of culture solution in the medium and controlling the supply of the culture solution based on the detected amount of culture solution. 2. In a system for cultivating plants by using a culture medium and supplying a culture solution such as water or an aqueous fertilizer solution, a chemical battery is constructed by attaching a pair of electrodes made of different metals to the medium and using the culture solution, A detection section for detecting the electromotive force between the electrodes is provided, and a PH sensor for detecting the pH of the culture solution in the medium is provided at an appropriate location, and the detection section detects an amount corresponding to the electromotive force between the electrodes, and the Detects the pH of the culture solution with a PH sensor,
Based on the correspondence between the pH of the culture solution and the electromotive force, the amount of culture solution in the medium is detected by correcting the amount corresponding to the electromotive force between the electrodes detected by the detection unit, and the detected amount of culture solution is A method for managing a culture medium in a plant cultivation system, the method comprising controlling the supply of a culture medium based on the following. 3 A plurality of pairs of electrodes are attached to the culture medium electrically integrated through the culture medium, and the detection unit includes an input unit that makes each electrode pair independent in AC and DC. A method for managing a culture medium in a plant cultivation system according to claim 1 or 2, characterized in that the method comprises: