JP2736333B2 - Hydroponics equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Industrial applications]

The present invention relates to hydroponic cultivation in which plants are cultivated with a nutrient solution, and more particularly to a hydroponic cultivation apparatus that uses a capillary water-absorbing sheet that performs capillary water absorption as a plant cultivation floor.

[Prior art]

Conventionally, a capillary water-absorbing sheet is placed on a support table at a position higher than the nutrient solution level, and the plant cultivation surface on the upper surface of the sheet is set at a higher position than the nutrient solution level. There is a type in which a nutrient solution is sucked from a liquid part and placed on a cultivation surface to grow a plant, or a type in which a nutrient solution is dropped on a sheet on an inclined surface from above.

[Problems to be solved by the invention]

Conventionally, the plant cultivation surface is a method of sucking nutrient solution at a position higher than the liquid contact part of the nutrient solution, so there is a limit to the amount of water absorption, and when the plant water absorption is at its peak, the amount of water absorption may be insufficient in capacity. If the cultivation surface to be sucked is not placed in a considerably wet state, the water on the cultivation surface evaporates and salts accumulate, resulting in a highly concentrated solution, which is extremely inconvenient for the plant roots. In addition, when the nutrient solution is dropped on the sheet on the inclined surface from above through the pipe, it is difficult to maintain the level of the pipe, and thus the nutrient solution cannot be evenly dropped, resulting in uneven water supply. There is a risk. In addition, when the cultivation part was not surrounded by the covering cover, green algae were generated and nutrients were absorbed, and salt accumulation was caused by transpiration, which was inconvenient for plant roots. The present invention has been made in order to eliminate such a conventional problem, in which the water absorption at the root of a plant placed on a capillary water absorption sheet is not a suction of nutrient solution using the capillary water absorption sheet, but a water absorption. What uses the lowering, that is, the cultivation floor consisting of a capillary water absorption sheet, by absorbing the nutrient solution of uniform concentration by capillary, to generate a continuous capillary water absorption flow on the cultivation floor, to secure the water absorption of the plant, Cultivation.

[Means for Solving the Problems]

The present invention is a cultivation floor comprising a capillary water-absorbing sheet having a capillary phenomenon laid in a cultivation box, and a cultivation floor interposed with a multi-hole net sheet for holding a small space between the cultivation box bottom and the cultivation box. The nutrient solution is located at a position lower than the level of the nutrient solution in the nutrient solution water passage that is separated from the cultivation floor, and the nutrient solution is supplied to the upper end of the nutrient solution water channel and circulated, so that a uniform flow of the nutrient solution is obtained. In the resulting nutrient solution flow path, one end of the side surface of the long-length capillary water-absorbing sheet is brought into contact with the capillary water-absorbing sheet, drained from the other end, and the capillary water-absorbing sheet uses a drop in position to be continuous by capillary action. This is a hydroponic cultivation apparatus for cultivating plants by generating a natural nutrient solution flow.

【Example】

Hereinafter, description will be given based on the attached drawings. As shown in FIG. 1, a vertically long cultivation box 1
One end of the capillary water-absorbing sheet 2 having a capillary phenomenon placed thereon is partitioned in parallel with the longitudinal direction of the capillary water-absorbent sheet 2 and arranged at a higher position than the lowermost position of the capillary water-absorbent sheet Then, the liquid is inserted into the nutrient solution passage 3 provided so that the liquid level of the nutrient solution is located, and comes into contact with the liquid to absorb the capillary water. Capillary phenomena of sinking using the head drop of the nutrient solution held in the waterway,
The nutrient solution is continuously supplied to the front surface of the water absorbing sheet 2. Further, the plants placed on the capillary water-absorbing sheet are surrounded by the covering cover 5 excluding the plant stems so as to shield the plant roots from light above the capillary water-absorbing sheet 2 and maintain the wet state. It is cultivated. Then, the cultivation box 1 in which the capillary water-absorbing sheet is placed and the nutrient solution water passage 3 which is separated from the capillary water-absorbing sheet and arranged side by side is installed so as to have a downward slope in the long direction, is separately provided. The nutrient solution supplied from the nutrient solution tank 9 to the upper end of the nutrient solution water passage 3 by the pump 10 flows uniformly in the nutrient solution water passage 3, and the concentration of the nutrient solution is uniformly maintained throughout the elongate direction by flowing down. Capable, the capillary water-absorbing sheet 2 having one end in contact with the nutrient solution over the entire length of the nutrient solution can absorb the same concentration of the nutrient solution evenly. Growth differences resulting from differences in the nutrient solution concentration of plants can be reduced. If the plant cultivation floor 7 composed of the capillary water-absorbing sheet 2 is in close contact with the bottom of the cultivation box, there is a problem in terms of water absorption capacity and oxygen supply surface. Therefore, as shown in FIG. A multi-hole net 6 (see FIG. 3 (b)) capable of holding a small space is interposed between the two. Further, instead of integrating the capillary water-absorbing sheet 2, as shown in FIG. 2, two separated capillary water-absorbing sheets 2 ″ are used to form the falling portion from the nutrient solution water passage 3 ′ and plant cultivation. A sheet 2 ″ is placed near the contact portion 14 with the floor 7 so that the nutrient solution can be supplied by continuous capillary water absorption. In this way, the capillary water absorbing sheet 2 ″ at the falling portion can be appropriately selected from a sheet having a different capillary water absorbing amount or a sheet capable of coping with the water supply amount according to the plant by changing the thickness of the sheet. Next, as shown in Fig. 2, the capillary water supply sheet 2 ', 2 "
If a plate wall 8 is provided at the end face of the plant cultivation floor 7 to prevent the roots of the plant roots planted along the lengthwise direction, the plant roots enter the drainage channel 4 "and cause root rot. And, as shown in this figure, it is possible to prevent inconvenience of extending to the sheet joint portion 14. Then, the cultivation box 1 'is moved from the nutrient solution passage 3' to the cultivation box 1 '.
If a downward slope is formed toward the drainage side 4 ″, the continuous flow of the nutrient solution by suction of capillary penetration is performed smoothly, so that the nutrient solution can flow down the cultivation surface evenly without stagnation. The capillary water-absorbing sheet 2 ′, 2 ″ has a capillary phenomenon, and its continuous pores are preferably about 10 to 200 μm. If present, the plant root hardly penetrates, and the plant root extends almost along its surface and absorbs water. Further, the sheet has a similar function, such as a three-dimensional foam molded product with continuous pores of synthetic resin such as polyvinyl alcohol, a synthetic resin processed molded product, a sintered ceramic molded product, and the like, and It is also used as a combination of these.

[Action]

In FIG. 4, the nutrient solution supplied from the nutrient solution tank 9 to the upper end of the nutrient solution water passage 3 by the pump 10 flows uniformly through the nutrient solution water passage 3, and the concentration of the nutrient solution is reduced in the longitudinal direction by flowing down. Since it can be held evenly throughout, the capillary water-absorbing sheet 2 can absorb the nutrient solution of the same concentration from all one end, and for plants planted at a required interval, the growth can be achieved by absorbing the nutrient solution of the same concentration. It will be the same. In a method in which a nutrient solution flows down onto a thin film having a thickness of several mm, as in a known thin film hydroponic method of the NFT method, it is difficult to uniformly flow down an impermeable cultivation bed, and a water path is formed on a plant root. It is difficult to supply water uniformly, and since the nutrient solution is supplied in series to the plants, it is difficult to supply a uniform concentration to each plant. On the other hand, the flow of the nutrient solution by the capillary water absorption of the present invention is such that the capillary water absorption sheet itself of the cultivation bed 7 is a continuous space of micropores, so that the entire sheet is always evenly dispersed and the swollen state is maintained. Since the nutrient solution flows down and is supplied in parallel to each plant, a nutrient solution having a uniform concentration can be supplied to each plant. The roots of the plant 12 extend so as to crawl on the cultivation floor 7, and can absorb sufficient nutrient solution from the cultivation floor of the capillary absorbent sheet on the contact surface as much as necessary for the roots. Always shaded, water drops on cover due to transpiration
Since 15 is attached and kept in a wet state in which it is dripped, the formation of the root mat is also good, and the water absorption is left to the roots of the plants, and the roots of the plants select water absorption. To prevent the plant roots on the capillary water-absorbing sheets 2 to 2 "from extending to the nutrient solution passages 3 to 3 'and the drainage passages 4, 4",
If the plate wall 8 is provided and blocked, root rot due to root invasion can be prevented. The multi-hole net having an appropriate narrow space so that the capillary water-absorbing sheets 2-2 "and the bottom of the cultivation box 1 and 1 'adhere to each other in the flow state of the capillary water-absorbing water so as not to be unfavorable in terms of oxygen supply or water supply. A good state can be obtained by holding the intermediary 6. The cultivation box 1 in which the nutrient solution water passage 3 is provided is horizontally disposed, and water is stopped at both ends in a weir shape. Nutrient passage 3,3 '
If one end is supplied with a nutrient solution by a pump or the like, and the other end is returned to the nutrient solution tank 9 by the amount equal to or more than the required amount by the dam, the pump 10 is periodically turned on by the timer 11 several times a day. When the nutrient solution is supplied cyclically by operation, the stored nutrient solution in the nutrient solution passages 3 and 3 'may be absorbed by capillary water, even if the pump cannot be operated due to a power failure etc. It can respond while being sucked. Furthermore, the cultivation box 1 in which the nutrient solution passage 3 is installed,
If the nutrient solution is disposed on the downward slope, the nutrient solution supplied to the upper end of the nutrient solution passage 3 flows uniformly, and the flow rate of the nutrient solution increases. If it circulates to return to the nutrient solution tank from the other lower end,
A nutrient solution having a uniform concentration can be evenly supplied to each plant through the capillary water absorbing sheet 2. The nutrient solution that has flowed through the capillary water-absorbing sheet 2 on the plant cultivation floor is absorbed by the roots of the plant, and excess nutrient solution is drained from the drainage channel 4.
It is better to treat this discharged liquid without returning it to the nutrient solution tank 9. That is, when this discharged liquid is returned to the nutrient solution tank 9, fluctuations in the nutrient solution concentration, diffusion of pathogenic bacteria, adverse effects of root secretions, and the like are added to the nutrient solution. In other words, the nutrient solution in the nutrient solution passage 3 circulates to make the whole a uniform concentration,
The nutrient solution absorbed by the plant is discharged and processed without recirculation. This makes it easier to manage the culture solution. As described above, since the supply of the nutrient solution of the present invention is of a suction type utilizing the capillary phenomenon by the capillary water absorbing sheet,
Even if the liquid level fluctuates somewhat, the nutrient solution can be easily dispersed uniformly and allowed to flow down. On the other hand, in the conventional supply method by injection in which a large number of small holes are intermittently drilled in a pipeline, it is difficult to maintain the horizontal level of the pipeline, and the supply is uniformly performed from each small hole due to pipeline resistance and the like. Therefore, the supply of the nutrient solution by the capillary water-absorbing sheet is excellent also from this point. At the time of plant removal after the end of cultivation, plant roots hardly penetrate inside the capillary water-absorbing sheet and are formed in layers,
The roots can be easily separated from the cultivation surface. As an example, a cultivation comparison experiment was conducted using the apparatus shown in FIG. 1 with the conventional NFT method and the capillary water-absorbing sheet method of the present invention in which the NFT method was modified to provide a partition wall of a water passage. As a capillary water absorbing sheet, A: a soft sponge sheet having a large water absorption, B: a hard sponge sheet having a small water absorption, C:
Four types of corrugated sheet of a hard sponge sheet having a small water absorption and D: a synthetic fiber sheet having a large water absorption were used. As an outline of the cultivation, the test varieties of tomato "Momotaro" were sown on a 5cm square rock wool cube on January 20, transplanted into a 10cm square cube, and then placed in a Six Lighthouse on March 19 Planted on the floor. As the cultivation floor, a 30 cm wide channel was divided into a 5 cm water channel and a 25 cm bed, and five beds with a length of 10 m were installed. On the four cultivation floors, water-absorbing sponge sheets A, B, and C and a synthetic fiber sheet D were laid on the cultivation floors, and one end of the side was in contact with the water passage. The other floor was an NFT cultivation floor with no water-absorbing sheet and only a thin-film nutrient solution flow for comparison. 20 plants were planted per cultivation floor. As a culture solution, a horticultural test formulation was used, and the electric conductivity indicating the concentration of the culture solution was increased from 0.5 mS to 1.8 mS with growth. In addition, the amount of water reduction was investigated every 3 to 7 days, and each time the amount of the water reduction was added to the culture solution. The minimum temperature in the greenhouse and the minimum temperature of the culture solution were heated so as to be 6 ° C. and 18 ° C., respectively. Test results As a summary of the test results, in the capillary water-absorbing sheet of the present invention, as compared with the conventional NFT method, the yield of tomato was not inferior, and the sugar content was clearly higher in the B-sponge sheet having low water absorption. The B sponge sheet had a small water absorption, so that the water stress was strongly affected. Therefore, the sugar content was high, and conversely, the NFT and the sheet having a large water absorption had a low sugar content. Looking at the foliage weight at the end of cultivation, A sponge sheet, D synthetic fiber sheet, and NFT, which have high water absorption, are large, which means that vegetative growth was promoted in those sections. Looking at the daily water absorption, a difference was observed in the test section from around the middle of May, and in the late cultivation, the water absorption was significantly reduced in the B sponge sheet. Thus, in the method of the present invention,
It was found that if the raw materials for the capillary water-absorbing sheet were properly selected, the cultivation technique would be sufficiently practical.

According to the present invention, a capillary water absorbing sheet having a capillary phenomenon is used, and one end of this sheet is arranged at a position lower than the liquid level of the nutrient solution, and the capillary suction flow is brought into contact with the nutrient solution. Therefore, the plant cultivation floor of the capillary water-absorbing sheet generates a continuous capillary water-absorbing flow using a head drop to supply nutrient solution to the plant roots. Since this capillary water absorption flow does not cause the nutrient solution having a thickness of about several mm to flow down to the impermeable surface unlike the thin film hydroponic method of NFT, the flow of the nutrient solution is not clear to the naked eye, and it is just placed in a bucket. The rags are like a swollen state that makes the water inside swell, so that the nutrient solution flows down evenly over the entire plant cultivation floor, so that the road is blocked like the NFT method,
Alternatively, water absorption can be selected for the plant roots and the water absorption can be left to the root requirements. In addition, since the plant cultivation floor of the capillary water-absorbing sheet is surrounded by the covering cover, the plant cultivation surface always shields the plant roots, and is kept in a wet state by suppressing transpiration by the covering cover. The capillary flow does not deteriorate and salt accumulation damage does not occur. If the capillary water-absorbing sheet is divided into two sheets, and the sheet that comes into contact with the nutrient solution passageway is replaced appropriately by changing the capillary water-absorbing amount or by adjusting the sheet thickness, it is suitable for plants. The selected capillary water absorption can be selected. Furthermore, in order to prevent adhesion between the capillary water-absorbing sheet and the bottom of the cultivation box, the capillary water-absorbing sheet itself is molded into an uneven shape, or a multi-hole net for space retention is interposed between the capillary water-absorbent sheet and the bottom of the cultivation box. In addition, if it is possible to cope with the capacity of capillary water absorption and oxygen supply, and if the capillary water absorption sheet near the nutrient solution storage tank is provided with a plate wall to prevent the growth of plant roots, the plant will not enter the Nega canal, Root rot can be prevented. In addition, if the nutrient solution flow path is inclined down, the function of the nutrient solution can be maintained evenly by the flow of the nutrient solution, and the nutrient solution of the same concentration throughout the whole can be evenly distributed from the side by the capillary water absorption sheet. Therefore, the growth difference caused by the difference in the nutrient solution concentration of the plant can be reduced. If the nutrient solution in the nutrient solution passage is circulated to maintain the concentration of the nutrient solution evenly and to replenish the reduced water absorption, the remaining nutrient solution absorbed by the plant will not be drained and used for cultivation. Liquid management becomes easier. In addition, as can be seen from the test results of the examples, the performance of the present invention does not differ greatly from the conventional NFT method in the yield of tomato, as shown in Table 1. The sugar content, which is a quality indicator, is higher than that of the NFT method because the water stress acts on the capillary water-absorbing sheet moderately, so that a high quality product can be obtained. Furthermore, the advantages of the present invention are that the plant root and the cultivation bed can be easily separated after the cultivation, and that the cultivation bed can be used as many times as it has almost no remaining roots.

[Brief description of the drawings]

FIGS. 1 and 2 are vertical sectional views cut perpendicular to the longitudinal direction of different embodiments of the present invention, and FIG. 3 (a) is a partial sectional view of a plant cultivation floor with a multi-hole net interposed therebetween. , (B) is a perspective view of the multi-hole net, and FIG. 4 shows a simplified system diagram of a circulating system for cultivation. In the figure, 1,1 '... cultivation box 2,2' ... Kesuga water sheet 3,3 '... nutrient solution passage 4,4 ", 4" ... drain passage 5 ... cover cover 6 ... ... Multi-hole net 7... Plant cultivation floor 9... Nutrient tank 10... Pump 11... Timer 12... Plant 14.

Claims (1)

(57) [Claims] 1. A cultivation floor comprising a capillary water-absorbing sheet having a capillary phenomenon and placed in a cultivation box, wherein a multi-hole net sheet for holding a narrow space is interposed between the cultivation box and the bottom of the cultivation box. However, the nutrient solution is located at a lower level than the nutrient solution level of the nutrient solution channel that is juxtaposed with the cultivation floor. By supplying the nutrient solution to the upper end of the nutrient solution channel and circulating it, the nutrient solution is evenly distributed. To the nutrient solution flow path that generates a flow, one end of the side surface of the capillary water-absorbing sheet is brought into contact with the capillary to absorb water, and drained from the other end.
Along with generating a continuous flow of nutrient solution by capillary action, surrounding the capillary water-absorbing sheet with a covering cover excluding the plant stem, cultivating the plant placed on the capillary water-absorbing sheet. Characteristic hydroponic cultivation equipment.