JPH0354535B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a plant cultivation nutrient solution preparation device used for hydroponic cultivation, etc., and in particular, it relates to a plant cultivation nutrient solution preparation device for use in hydroponic cultivation, etc., and in particular, a highly concentrated undiluted solution of a nutrient solution necessary for cultivation such as fertilizer. and the dilution of highly concentrated nutrient solutions with agricultural water, etc.

[Conventional technology]

In contrast to conventional soil cultivation, which uses soil, plants are planted in artificial culture media such as fibrous materials, and nutrients such as fertilizers necessary for growth are dissolved in water. There is culture medium cultivation in which cultivation is carried out by supplying liquid.

Compared to soil cultivation, this type of culture medium cultivation has excellent characteristics, such as being more hygienic, allowing optimal growth conditions to be set for each cultivated plant, and easy cultivation management. , management of nutrient solution concentration, etc. is extremely important.

FIG. 2 shows an outline of a general hydroponic apparatus for growing plants. This hydroponic cultivation device uses a nutrient solution mixing and diluting device 2 along with dilution water Wr such as agricultural water.
A highly concentrated nutrient solution (hereinafter referred to as undiluted solution M) containing dissolved fertilizer, etc. as the basis of Wm is supplied from the undiluted solution tank 4, and this undiluted solution M is mixed with dilution water Wr.
By diluting the concentration of , a nutrient solution Wm with a fertilizer concentration suitable for plant cultivation is obtained.

Then, this nutrient solution Wm is sent to the cultivation area 10 via a nutrient solution supply device 6 consisting of a pressure pump, a filter, etc., and a supply pipe line 8. In the cultivation area 10, a plurality of branch pipes 12 attached to the supply pipe line 8 are arranged in the vicinity of the bed 16 in which the plants 14 are planted, and a drip nozzle 18 as a supply nozzle is connected to each branch pipe 12 for each plant. will be established. Therefore, the nutrient solution Wm pumped through the supply pipe 8 is
It is dripped and supplied to the vicinity of plants from a drip nozzle 18 via a branch pipe 12.

[Problem that the invention seeks to solve]

In this type of hydroponic cultivation, the formulation of the nutrient solution Wm is as follows:
It is necessary to set the optimal fertilizer distribution and concentration for the plants 14, and the fertilizer distribution and concentration differ from plant to plant and also vary greatly depending on their growth state and weather conditions. In each case, it is necessary to set the fertilizer distribution and concentration of the nutrient solution Wm while referring to growth data and weather data.

Conventionally, in mixing and diluting the nutrient solution Wm for diluting the stock solution M by mixing it with the dilution water Wr, the dilution water
The amount of raw solution depends on the flow rate wr to inhale and draw Wr.
In a diluter that obtains the nutrient solution Wm by setting mn, the dilution ratio of the stock solution M fluctuates depending on the flow rate wr and pressure of the dilution water Wr, making it impossible to obtain a constant concentration of the nutrient solution Wm. It was not possible to change the concentration. Therefore, when the dilution ratio changes, it is necessary to change the fertilizer concentration of the stock solution M, which requires very troublesome work.

In addition, as a way to automate the conventional preparation of nutrient solution Wm, a certain amount of dilution water is added to the nutrient solution mixing and diluting device 2.
After incorporating Wr, stock solution M with a specific concentration is added to it.
There is a method in which the necessary concentration is set by gradually adding Wm and monitoring the concentration of the nutrient solution Wm using a concentration sensor. This is because the nutrient solution Wm is prepared by taking in the dilution water Wr in fixed amounts, so there is no need to continuously correct the concentration. Continuous supply control of the nutrient solution Wm cannot be performed, and the nutrient solution
In order to set Wm to a constant concentration, an expensive concentration sensor was required.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a plant cultivation nutrient solution mixing device that continuously mixes a nutrient solution with a required concentration in accordance with supplied dilution water to achieve the required concentration.

[Means for solving problems]

The plant cultivation nutrient solution preparation device of this invention has a dilution water
Dilution water supply line where Wr is supplied (supply line 30)
and a nutrient solution supply path (supply path 34) that is to supply nutrient solution to the culture medium (cultivation area 10), receives dilution water from the dilution water supply path, and uses this dilution water to 2. Dilute the stock solution Ma, Mb or both to make a nutrient solution.
A nutrient solution mixing diluter 22 that forms Wm and flows out the nutrient solution to the medium side according to the water pressure of the dilution water.
and a first stock solution tank 2 for storing the first stock solution.
8A, a second stock solution tank 28B that stores the second stock solution, and a stock solution supply path between the first stock solution tank and the nutrient solution mixing diluter, and a second stock solution tank 28B that stores the second stock solution. A first quantitative discharge device 26A that supplies the liquid to the liquid mixing diluter is disposed in a liquid supply path between the second stock liquid tank and the nutrient liquid mixing diluter, and is arranged in a liquid supply path between the second liquid liquid and the liquid mixing diluter. a second quantitative dispenser 26B that supplies the diluter;
a driving means (a fixed-rate dispenser drive circuit 32) that drives the fixed-rate dispenser; a flow rate sensor 20 that is arranged in the dilution water supply path and detects the flow rate of the dilution water;
The supply amount of the first or second stock solution to be supplied to the nutrient solution mixing diluter is calculated from the flow rate data from this flow rate sensor and the concentration data set in advance according to the cultivation conditions, and the calculation result is generates a control output based on the control output, operates the first or second metering dispenser through the drive means in accordance with the control output, and supplies the first stock solution, the second stock solution, or both stock solutions to the culture medium. The present invention is characterized in that it includes a control device 24 for controlling the amount of stock solution supplied to the liquid mixing diluter.

[Effect]

According to this cultivation nutrient solution mixing device, a stock solution amount mn can be obtained according to the concentration setting of the nutrient solution Wm and the flow rate of the dilution Wr, and the stock solution Ma, which is set to the stock solution amount mn, can be obtained.
Since Mb and the dilution water Wr are mixed, the amount mn of the stock solution is controlled in immediate response to fluctuations in the flow rate of the dilution water Wr, and the nutrient solution Wm of a set concentration is continuously prepared.

In this case, the preparation of the nutrient solution Wm consists of multiple stock solutions Ma,
When Mb is used, it is mixed and diluted with each stock solution Ma, Mb and dilution water Wr, and when a single stock solution M is used, it is mixed and diluted with that stock solution M and dilution water Wr.

In the plant cultivation nutrient solution preparation device of the present invention, the stock solution M is divided into first and second liquids having different components.
The fertilizer stock solution (stock solution Ma, Mb) or the fertilizer stock solution and the PH correction stock solution are used. By setting the blending ratio of stock solutions Ma and Mb, a nutrient solution Wm with desired components and concentration can be obtained.

In the plant cultivation nutrient solution mixing device of the present invention, the stock solution supply means is connected to the stock solution tanks 28A and 28B for storing the stock solution, the stock solution amount control means (the stock solution amount control device 24), and the output of the metering dispenser drive circuit 32. By providing the quantitative dischargers 26A and 26B that are controlled in this manner, necessary amounts of stock solutions Ma and Mb can be reliably supplied to the nutrient solution mixing and diluting means (the nutrient solution mixing and diluter 22).

〔Example〕

FIG. 1 shows an embodiment of the plant cultivation nutrient solution preparation device of the present invention.

For example, agricultural water such as groundwater or rainwater is used as the dilution water Wr for obtaining the nutrient solution Wm of a specific concentration. This dilution water Wr is continuously supplied from a tank or the like (not shown) through a supply pipe line 30 serving as a dilution water supply line. A flow rate sensor 20 is installed as a detection means, and the flow rate wr of the dilution water Wr is electrically detected by this flow rate sensor 20. Vwr indicates a flow rate signal representing the flow rate wr of dilution water Wr.

This dilution water Wr contains the first and second stock solutions Ma,
The nutrient solution is supplied to a nutrient solution mixing and diluter 22 arranged as a nutrient solution mixing and diluting means for mixing with Mb. The nutrient solution mixing diluter 22 may be, for example, a part of the supply pipeline 30, a pipeline with a large cross-sectional area formed in the supply pipeline 30, or a separate unit from the supply pipeline. A nutrient solution mixing and diluting device for preparing and storing the nutrient solution Wm may be installed, and this embodiment is constructed by installing a portion with a large cross-sectional area in a part of the supply pipe line 30.

Further, first and second stock solution tanks 28A and 28B are installed as stock solution storage means for storing first and second fertilizer stock solutions Ma and Mb, and the stock solutions Ma and Mb in these stock solution tanks 28A and 28B are as follows:
The nutrient solution is supplied to the nutrient solution mixing diluter 22 via first and second quantitative dischargers 26A and 26B, which serve as electrically controlled stock solution supply means. Stock solution Ma, Mb
For example, the necessary amount of the stock solution is supplied to the nutrient solution mixing diluter 22 through the metering dispensers 26A and 26B.
Ma or Mb is set to drip by gravity or a certain pressure.

Then, the flow rate signal obtained by the flow rate sensor 20
Vwr is applied to the stock solution amount calculation unit 241 of the stock solution amount control device 24, which is arranged as a stock solution amount control means. The stock solution amount calculation unit 241 calculates the stock solution amount mn necessary to obtain the concentration Xn from the flow rate data obtained by the constantly changing flow rate signal Vwr and the concentration data representing the concentration Xn set as necessary. Calculate. For example, this stock solution amount calculation section 241
For the flow rate data and concentration data, a storage means is installed that stores the raw solution volume data according to the flow rate data, and the necessary raw solution volume data is read out by inputting the flow rate data and concentration data. It's okay.

The stock solution amount signal Vmn representing the stock solution amount data calculated by the stock solution amount calculation section 241 is added to the stock solution amount supply control section 242 to generate the stock solution control signal Vcm necessary to supply the necessary stock solution amount. Occur. In this case, by simultaneously calculating the blending ratio of the stock solutions Ma and Mb and automatically setting the blending ratio of each stock solution Ma and Mb according to the concentration data, for example, the blending ratio can be obtained for determining the concentration. Therefore, the stock solution control signal Vcm is a data signal representing the amounts of stock solutions Ma and Mb and their blending ratio for setting the required concentration.

This stock solution control signal Vcm is applied to a metering discharge drive circuit 32 installed as a supply drive means for the stock solution supply means, and the metering dispenser drive circuit 32 outputs drive signals Va, Vb according to the stock solution control signal Vcm. Add to each metering dispenser 26A, 26B. The fixed quantity dispensers 26A and 26B receive the stock solution control signal Vcm
The opening/closing time is controlled according to the supply ratio of the stock solutions Ma and Mb set in The liquid is supplied to the liquid mixing diluter 22.

The supplied stock solutions Ma and Mb are stirred in the nutrient solution mixing diluter 22 according to the flow of the dilution water Wr to obtain the nutrient solution Wm of the required concentration, which is then used as a nutrient solution supply path on the cultivation field side. It is supplied through the supply path 34. In that case, the nutrient solution Wm is fed under pressure by the nutrient solution supply device 6 as shown in FIG. 2.

Therefore, according to such a nutrient solution mixing device, once the concentration of the nutrient solution Wm is set, the dilution water is
The necessary amount of stock solutions Ma and Mb are supplied and mixed according to the flow rate wr of Wr, and the supply amount of the necessary stock solutions Ma and Mb is controlled in response to fluctuations in the flow rate of dilution water Wr.
A nutrient solution Wm with a stable concentration can always be obtained. According to such concentration control, the stock solution Ma,
Since the concentration of Mb can be kept constant and a mixing dilution tank or concentration sensor is not required, an inexpensive system can be constructed. In addition, the stock solution amount control device 24 is composed of an arithmetic processing device such as a microcomputer,
It is possible to control the amount of stock solution.

In the embodiment, the first and second stock solution tanks 28A and 28B are installed to store two types of stock solutions Ma,
We have explained the case of using Mb, but it is possible to mix fertilizers with the necessary ingredients in advance and set up the necessary stock solution tank, or to install a stock solution tank for each fertilizer to avoid inconveniences caused by combinations of fertilizers. , fertilizer may be mixed according to the concentration settings.

Further, in this invention, the fertilizer stock solution is stored in the first stock solution tank 28A, and the PH is stored in the second stock solution tank 28B.
If the concentration correction stock solution is stored, it can be used to correct the PH concentration.

〔Effect of the invention〕

As explained above, according to the present invention, the necessary amount of stock solution is calculated for the flow rate of dilution water according to the concentration setting of the nutrient solution, and the amount of stock solution is controlled based on the calculation result. The amount of stock solution can be controlled immediately in response to fluctuations in the flow rate of the nutrient solution, and the nutrient solution at a set concentration can be constantly mixed, diluted, and continuously supplied to the culture medium through continuous preparation. By freely setting the nutrient solution and stably supplying a nutrient solution with an appropriate concentration, it is possible to grow plants, and it is also possible to downsize the equipment and reduce the installation area.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the plant cultivation nutrient solution mixing device of the present invention, and FIG. 2 is a block diagram showing an outline of a general plant nutrient solution mixing device. Wm... Nutrient solution, Wr... Dilution water, Ma... First stock solution, Mb... Second stock solution, 20... Flow rate sensor, 22... Nutrient solution mixing diluter, 24... Stock solution amount control device , 26A...first fixed amount dispenser, 26B...
...Second quantitative dispenser, 28A...First stock solution tank, 28B...Second stock solution tank.

Claims (1)

[Scope of Claims] 1. A dilution water supply channel that is inserted between a dilution water supply channel to which dilution water is supplied and a nutrient solution supply channel that is to supply nutrient solution to the culture medium to receive dilution water from the dilution water supply channel; a nutrient solution mixing diluter that dilutes the first or second stock solution or both with dilution water to form a nutrient solution, and flows out the nutrient solution to the medium side according to the water pressure of the dilution water; a first stock solution tank for storing the stock solution; a second stock solution tank for storing the second stock solution; a stock solution supply device installed between the first stock solution tank and the nutrient solution mixing diluter; a first quantitative discharge device for supplying a first stock solution to the nutrient solution mixing diluter; a second quantitative discharge device for supplying the stock solution to the nutrient solution mixing diluter; a driving means for driving the first or second quantitative discharge device; installed in the dilution water supply path to control the flow rate of the dilution water. a flow rate sensor that detects the flow rate; and a supply amount of the first or second stock solution to be supplied to the nutrient solution mixing diluter based on the flow rate data from this flow rate sensor and concentration data set in advance according to cultivation conditions. is calculated, and the first or second metering dispenser is operated through the drive means in accordance with a control output based on the calculation result, and the first stock solution, the second stock solution, or both stock solutions are supplied to the culture medium. A plant cultivation nutrient solution blending device comprising: a stock solution amount control device for supplying to a solution mixing diluter; 2. The plant cultivation nutrient solution mixing device according to claim 1, wherein the first and second stock solutions consist of fertilizer stock solutions with different components, or a fertilizer stock solution and a PH correction stock solution.