JP5538505B2 - Hydroponics equipment - Google Patents

Description

  The present invention relates to a hydroponic cultivation apparatus, more specifically, a combination of a liquid-type hydroponic method and a capillary-type hydroponic method, using a nutrient solution without using soil, for example, plants (fruit vegetables such as tomatoes, leaf vegetables, flowering trees, etc. A hydroponic cultivation device for growing

In recent years, hydroponics devices have been developed to stably supply plants such as tomatoes to the market without being affected by the weather.
Conventionally, as a kind of hydroponic cultivation apparatus, for example, a “hydroponic cultivation apparatus” of Patent Document 1 is known. This “nourishing liquid cultivation device” has a long rectangular container-shaped cultivation tank whose inner surface is covered with a waterproof sheet, and stores the nutrient liquid in the liquid storage space of the cultivation tank and grows only with the nutrient solution. Hydroponics that employs a combination of the hydroponic method and the capillary-type hydroponic method that absorbs the nutrient solution by the capillary force of the water-absorbing sheet and supplies the nutrient solution to the roots of the tomatoes. Device.

JP-A-4-370044

However, the “hydroponic cultivation apparatus” of Patent Document 1 has the following problems.
Conventionally, unfoamed hard plastic has been employed as a material for cultivation tanks. For this reason, the weight of the cultivation tank is large, and during installation of the apparatus on site, the worker is forced to work hard for a long time, and the apparatus cost is high.
In addition, the “hydroponic cultivation apparatus” of Patent Document 1 was used to continuously produce tomatoes after removing Pisium bacteria and other water-soluble bacteria by washing and drying the entire apparatus after use. However, for example, fungi having a spore cell structure with high drought resistance such as spore bacteria have a strong reproductive ability even after washing, and when the bacteria adhere to the cultivation tank, once the expensive cultivation tank is used. Since it was only used, it had to be disposed of, and running costs and equipment costs were rising.
Conventionally, rock wool has been adopted as a material for a water retention medium in which tomato seedlings are planted. Rock wool is an artificial mineral that is difficult to reduce naturally. Therefore, used rock wool after harvesting tomatoes must be disposed of as industrial waste, which has been a problem from the viewpoint of environmental conservation. Moreover, the cost of disposal of used rock wool has been one of the causes of the price increase of tomatoes.
Furthermore, the rock wool planted with seedlings was placed on the water-absorbent sheet in a state where the roots were blocked by the water-permeable root-proof sheet so that the roots did not extend to the nutrient solution.

Furthermore, the nutrient solution is sucked up into the rock wool only from the lower surface of the rock wool. Therefore, the surface area of the rock wool nutrient solution water absorption surface is small, and the nutrient solution cannot be sufficiently supplied to the tomato seedlings.
Moreover, the single layer nonwoven fabric which adhere | attached only the short synthetic resin fiber spotly with the adhesive agent was employ | adopted as a water absorbing sheet. Therefore, the supply of nutrient solution to the roots of tomatoes is not sufficient, and the additives contained in the adhesive inhibit the growth of tomatoes, and the harmful substances contained in the additives affect the health of humans who have eaten tomatoes. There was a risk of giving.
By the way, conventionally, as a water retention medium mounting table for placing a water retention medium on a liquid storage space, a planting float (floating island) that is separated from the upper part of a cultivation tank and floats on water is known. In order to facilitate distribution of the roots extending downward from the water retention medium to the left and right liquid storage space portions from the water retention medium mounting table, it is desirable that the planting float is disposed at an intermediate portion in the width direction of the liquid storage space. However, since the planting float is a floating island that floats the liquid level of the nutrient solution, it is difficult to position it in the middle of the liquid storage space in the width direction unless a new positioning member (fixed string, fixing rod, etc.) is used. Met.

  Therefore, as a result of earnest research, the inventor constructed the cultivation tank from foamed synthetic resin, and in order to prevent solution leakage when the cultivation tank weakened by adopting this material, The formation wall is covered with a single synthetic resin film from the inside, plug seedlings that do not contain rock wool are used as the water retention medium, and a water-permeable root-proof sheet is not required. A three-layer structure in which fibers are entangled by the water jet method as a water-absorbing sheet (lower partial water-absorbing sheet and upper partial water-absorbing sheet). In addition to the non-woven fabric, the intermediate part in the width direction of the resin film for preventing water leakage is covered with the fixed plant float, and the fixed plant float is placed in the intermediate part in the width direction of the storage space of the cultivation tank. If configured to position, and found that to solve all the above problems, and completed the present invention.

  This invention makes it possible to reduce the weight of the cultivation tank, facilitate installation of the apparatus on site, prevent leakage of the nutrient solution outside the apparatus when the cultivation tank is damaged, and reduce the equipment cost. Disposal costs as industrial waste and a water-permeable root-proof sheet are not required, and the nutrient solution can be sufficiently supplied to the seedlings, and the planting float can be easily positioned in the middle in the width direction of the storage space of the cultivation tank An object of the present invention is to provide a hydroponic cultivation apparatus that combines a submerged hydroponic method and a capillary hydroponic method.

  The invention according to claim 1 is a cultivation tank made of a foamed synthetic resin having a nutrient solution storage space therein, a planting float floating on the liquid level of the nutrient solution stored in the solution storage space, and A resin film for preventing water leakage that covers the formation wall of the liquid storage space of the cultivation tank from the inside and positions the fixed planting float in the middle in the width direction of the liquid storage space by covering the fixed planting float from above. A water-absorbing sheet placed on the planting float and having an end disposed below the surface of the nutrient solution, and a water-absorbing sheet that does not contain rock wool and is placed on the upper surface of the planting float The water-absorbing sheet has an end portion disposed below the surface of the nutrient solution, and a lower partial water-absorbing sheet on which the plug seedling is placed, and the plug seedling The upper part water-absorbing sheet covering from the bottom The partial water-absorbing sheet and the upper partial water-absorbing sheet each include an intermediate layer containing pulp short fibers between a first surface layer containing synthetic resin short fibers and a second surface layer containing synthetic resin short fibers. It is the hydroponic cultivation apparatus which consists of a nonwoven fabric of the 3 layer structure arrange | positioned so that a short fiber may be entangled.

The hydroponics apparatus here is an apparatus that combines a liquid-type hydroponic method and a capillary-type hydroponic method.
Examples of cultivated plants that can be used include tomatoes, strawberries, lettuce, green onions, and melons. The plug seedling refers to a seedling that has been seeded in a plastic multi-hole seedling raising tray called a plug tray and has been grown until it can be transplanted (fixed planting). Here, rock wool is not included as a water retention medium.
As the nutrient solution, for example, a high concentration solution EC10, a salt mixed solution, or the like can be adopted. In particular, water stress is given to large-sized tomatoes during cultivation to suppress water inflow to the fruit, and EC (salt concentration, electrical conductivity) of the nutrient solution is set to 1.5 to 5.0, for example. It is also possible to adjust the osmotic pressure to the roots and trunks of tomatoes to promote the accumulation of sugar in the tomato fruit and to have a sugar content of 7-8.
The "cultivation tank" here is a container for hydroponically cultivating cultivated plants. The shape of the cultivation tank is arbitrary. For example, a rectangular container shape may be used.
As a foaming synthetic resin which is a raw material of a cultivation tank, a polystyrene foam is employable, for example.

As a material for the planting float, synthetic resin (including foamed synthetic resin), wood, or the like having a specific gravity smaller than that of the nutrient solution can be used. Specific examples include various buffer materials and resin (rubber) tubes. Further, the planting float may be supported mechanically near the liquid surface using a hanging string, a hanging rod, a submerged column, or the like.
As the water leakage preventing resin film, for example, an agricultural film made of vinyl chloride resin or polyolefin resin can be employed.

The water absorbent sheet is a sheet having water absorption and water retention of the nutrient solution, and includes a lower partial water absorbent sheet and an upper partial water absorbent sheet. The lower partial water absorbent sheet and the upper partial water absorbent sheet may be the same nonwoven fabric or different nonwoven fabrics. As a preferred water absorbent sheet, for example, “Cook Up Kitchen Cloth” manufactured by Unicharm Co., Ltd. can be employed.
As the lower partial water absorbent sheet, the length is substantially the same as the length of the planting float, and when the width is placed on the planting float at the time of use, both ends in the width direction are arranged below the surface of the nutrient solution. The thing with length can be employ | adopted.
The upper partial water absorbent sheet has a size (wideness) that can cover the plug seedling of the cultivated plant from above, and at least a part of the upper partial water absorbent sheet comes into contact with the lower partial water absorbent sheet during use, and is fed from the lower partial water absorbent sheet. It is sufficient if a part of the liquid can be supplied to the surface of the plug seedling.
The first surface layer and the second surface layer may be either front or back when in use. The first surface layer and the second surface layer may be the same synthetic resin short fiber or different synthetic resin short fibers. The first surface layer and the second surface layer only need to contain synthetic resin short fibers in at least one part, and may be other short fibers (for example, regenerated cellulose short fibers) or a mixed fiber layer with long fibers. .

As the synthetic resin short fibers, for example, polyester short fibers, polyolefin short fibers, and the like can be employed.
The short pulp fibers in the intermediate layer are a kind of plant fibers, which are obtained by mechanically and chemically treating a plant such as wood to loosen cellulose fibers and pulping them. The intermediate layer only needs to contain at least pulp short fibers, and may be, for example, another short fiber (for example, synthetic resin short fiber) or a mixed fiber layer with long fibers.
As a short fiber entanglement method, for example, a water jet method, a needle punch method, a steam jet method, or the like can be employed.

According to a second aspect of the present invention, the first surface layer is a nonwoven fabric made of a mixed fiber of 63 to 87% by weight of polyester short fibers and 13 to 37% by weight of rayon short fibers, and the second surface layer is The hydroponic according to claim 1, wherein the intermediate layer is a non-woven fabric composed of 100% by weight of pulverized pulp, and is a non-woven fabric composed of a mixed fiber of 60-80% by weight polyester short fibers and 20-40% by weight pulp short fibers. It is a cultivation device.
The pulverized pulp refers to a finely pulverized pulp finished in a cotton form.

Invention of Claim 3 is the hydroponic cultivation apparatus of Claim 1 or Claim 2 which made the width | variety of the said upper part partial water absorption sheet shorter than the width | variety of the said fixed planting float.
The width of the “upper partial water absorbent sheet” is the length in the direction (width direction) perpendicular to the length direction when the upper partial water absorbent sheet is placed on the fixed planting float via the lower partial water absorbent sheet. Say it.
The width of the upper partial water absorbing sheet is 50 to 95% of the width of the fixed plant float. If it is less than 50%, a plug seedling of a general size cannot be sufficiently covered from above. Further, if it exceeds 95%, the upper partial water absorbent sheet is slightly displaced and the upper partial water absorbent sheet hangs down from the edge in the width direction, and between the upper partial growth sheet and the lower partial growth sheet. The direction of the growing bud may be downward, and the tip may be immersed in the nutrient solution of the cultivation tank to rot the bud.

According to invention of Claim 1, in the hydroponic cultivation apparatus which combined the submerged hydroponic method and the capillary hydroponic method, since the cultivation tank was produced from the foaming synthetic resin, weight reduction was achieved and to the spot This makes it easy to install the apparatus and reduces the cost of the cultivation tank. Moreover, if the foamed synthetic resin is employed in this way, the cultivation tank becomes weaker and more easily damaged than those made of an unfoamed hard synthetic resin. Then, the formation wall of the storage space of the cultivation tank is covered with a resin film for preventing water leakage from the inside. Thereby, the nutrient solution leak at the time of the failure | damage of a cultivation tank can be prevented.
In addition, the planting float floats and sinks depending on the level of the nutrient solution stored in the cultivation tank, so that the roots of the cultivated plant can automatically respond to changes in the water level of the nutrient solution. It becomes easy to manage the amount of nutrient solution in the tank.
Furthermore, since the planting float is positioned in the middle part in the width direction of the storage space of the cultivation tank by covering a part of the resin film for preventing water leakage (for example, the middle part in the width direction) on the planting float, The float can be easily positioned at the intermediate portion in the width direction of the liquid storage space of the cultivation tank.

Furthermore, since plug seedlings that do not contain rock wool are employed as the water retention medium, disposal of used rock wool as industrial waste, which was necessary in the case of conventional devices, is not required, and the disposal cost is not incurred.
Furthermore, in the case of a hydroponic cultivation apparatus that combines the submerged hydroponic method and the capillary hydroponic method as in the present invention, in the conventional apparatus, the water permeability is blocked so that the root does not extend to the nutrient solution. A root-proof sheet was required. However, here, the water supply sheet is made disposable and is not used for continuous cultivation of cultivated plants after harvesting. Therefore, a water-permeable root-proof sheet becomes unnecessary. Moreover, if the resin film for preventing water leakage and the water supply sheet are made disposable, as in the case of the conventional device, it is possible to sterilize and dry the entire device every time the cultivated plant is cultivated once. The device can be reused. Even if bacteria grow in the cultivation tank, the cultivation tank is made of low-cost foamed synthetic resin, so it can be re-used compared to the conventional device with a hard plastic cultivation tank even if it is disposable including the cultivation tank. Cost for use can be reduced.

Furthermore, as the water absorbent sheet, a two-ply-up type that wraps the plug seedling from above and below with the lower partial water absorbent sheet and the upper partial water absorbent sheet that are partially in contact with each other is adopted. The liquid reaches the upper partial water-absorbing sheet and can sufficiently supply the nutrient solution to the plant seedling.
Furthermore, when integrating the three nonwoven fabric layers of the first surface layer, the second surface layer, and the intermediate layer as the water absorbent sheet (lower partial water absorbent sheet and upper partial water absorbent sheet), the respective short fibers are, for example, Because it was entangled by the water jet method etc., the additive contained in the adhesive hindered the growth of the cultured plant or grew like a conventional water absorbent sheet consisting of a nonwoven fabric spot-bonded with an adhesive. There is no risk of harmful effects on people who eat food (such as fruits).

According to invention of Claim 2, the 1st surface layer of the nonwoven fabric which consists of a mixed fiber of polyester short fiber 63-87 weight% and rayon short fiber 13-37 weight%, and polyester short fiber 60-80 weight % And a second surface layer of a nonwoven fabric made of a mixed fiber of 20 to 40% by weight of a short pulp fiber and an intermediate layer of a nonwoven fabric made of 100% by weight of a pulverized pulp were laminated to make a water-absorbing sheet, which is more difficult to break. Thus, a water-absorbing sheet having high shape retention and high water absorption can be obtained. That is, a large amount of nutrient solution can be retained in these three nonwoven fabric layers, particularly an intermediate layer made of pulverized pulp, and the nutrient solution can be sufficiently supplied to the plug seedling. In addition, since the first surface layer and the second surface layer each contain high-strength polyester short fibers among the synthetic resin fibers, even if the water-absorbing sheet is immersed in the nutrient solution, the shape as the sheet is maintained and melted. Hard to tear.
In addition, since the first surface layer and the second surface layer contain polyester staple fibers that enhance the shape retention of the water absorbent sheet, both side edges in the width direction of the planting float of the lower partial water absorbent sheet It is difficult for the lower portion water absorbent sheet to be set at the contact portion. As a result, the nutrient solution can be smoothly sucked upward from the contact portion of the lower partial water absorbent sheet.

  According to invention of Claim 4, the width | variety of the upper side partial water absorption sheet was made shorter than the width | variety of the fixed planting float. Since the upper partial water absorbent sheet is put on the plug seedling, the buds that germinate and grow extend outward from the gap between the widthwise end of the upper partial water absorbent sheet and the lower partial water absorbent sheet. At that time, if the upper part water absorbent sheet is longer than the width of the planting float, the upper part water absorbent sheet hangs down from the edge in the width direction of the planting float, the grown buds grow toward the nutrient solution below, and the buds grow. Soaked in nutrient solution and easily rots. Therefore, here, the width of the upper partial water absorbent sheet was made shorter than the width of the planting float. Thereby, when the bud of the cultured plant extends outward from the gap between the widthwise end of the upper partial water absorbent sheet and the vicinity of the widthwise end of the planted float, the planted float end buds downward. The guide will not stretch. As a result, there is no possibility that the grown buds will be immersed in the nutrient solution and rot.

It is a principal part expanded longitudinal cross-sectional view of the hydroponic cultivation apparatus which concerns on Example 1 of this invention. It is a whole side view of the hydroponic cultivation apparatus concerning Example 1 of this invention. It is a principal part expansion perspective view containing the partial cross section of the hydroponic cultivation apparatus which concerns on Example 1 of this invention. It is a principal part expansion longitudinal cross-sectional view which shows the positioning operation | work by the water leak prevention resin film of the fixed planting float which comprises some hydroponic cultivation apparatuses which concern on Example 1 of this invention. It is a principal part expansion perspective view containing the partial cross section figure which shows the wrapping operation | work of the plug seedling by the lower part partial water absorption sheet | seat and the upper part partial water absorption sheet | seat in the hydroponic cultivation apparatus concerning Example 1 of this invention. It is a principal part expanded sectional view of the water absorption sheet | seat used for the hydroponic cultivation apparatus which concerns on Example 1 of this invention.

  Examples of the present invention will be specifically described below.

  1 to 3, reference numeral 10 denotes a hydroponic cultivation apparatus that combines the submerged hydroponic method and the capillary hydroponic method according to the first embodiment of the present invention. The hydroponic cultivation apparatus 10 has an internal space. A cultivation tank 12 made of expanded polystyrene (foamed synthetic resin) that has become the storage space 11 for the nutrient solution a, a fixed planting float 13 that floats on the liquid surface of the nutrient solution a stored in the storage space 11, and the cultivation tank 12. A resin film 14 for preventing leakage of water, which covers the formation wall of the liquid storage space 11 from the inside and positions the fixed plantation float 13 at the intermediate portion in the width direction of the liquid storage space 11 by covering the fixed plantation float 13 from above, and the fixed planting A water-absorbing sheet 15 placed on the float 13 and having an end disposed below the surface of the nutrient solution a, and a water-absorbing sheet 15 that does not contain rock wool and is placed on the upper surface of the planting float 13 Multiple tomato plugs 16, the water absorbent sheet 15 has an end portion disposed below the surface of the nutrient solution a, and a lower part water absorbent sheet 15A on which the plug seedling 16 is placed, and an upper part that covers the plug seedling 16 from above It consists of a water absorbing sheet 15B.

Hereinafter, these components will be specifically described.
The cultivation tank 12 is a horizontally long rectangular container, and is supported by a horizontally long single column 17 made of polystyrene foam at the intermediate portion in the width direction of the bottom plate over its entire length. The cultivation tank 12 has a thin cover plate 18 made of foamed polystyrene covering the upward opening. The cover plate 18 is provided for heat retention of the nutrient solution layer and protection of the seedling (including blocking of direct sunlight), and covers the opening of the cultivation tank 12 after planting.
The bottom wall and both side walls of the cultivation tank 12 are covered with a resin film 14 for preventing water leakage from the inside over the entire length of the liquid storage space 11. The resin film 14 for preventing water leakage is an agricultural film made of vinyl chloride resin, and its end in the width direction is folded back and covers the surfaces of both side walls of the cultivation tank 12.

As shown in FIG. 2, the nutrient solution a is circulated in the liquid storage space 11 of the cultivation tank 12 by the liquid circulation means 19 at 260 liters / minute. As the nutrient solution a, a nutrient solution dedicated to the apparatus is adopted. Moreover, in order to grow tomatoes having a sugar content of 7 or more, EC (salt concentration) of the nutrient solution a is set to 2.5.
The liquid circulation means 19 includes a nutrient solution supply unit 21 that supplies the nutrient solution a stored in the reservoir 20 into one end of the cultivation tank 12, and a drainage tank of the nutrient solution a from the other end of the cultivation tank 12. A nutrient solution discharger 23 for discharging the fluid to the wastewater tank 22, and a nutrient solution circulation unit 24 for returning the nutrient solution a stored in the drainage vessel 22 to the reservoir 20.
The storage tank 20 of the nutrient solution supply unit 21 is a large tank that stores 1800 liters of the nutrient solution a. The tank bottom of the liquid storage tank 20 and the liquid storage space 11 at one end of the cultivation tank 12 are communicated with each other by a supply pipe 26 having a first submersible pump 25 attached to the end on the liquid storage tank 20 side. The drainage tank 22 of the nutrient solution discharge unit 23 is a small water tank that stores 120 liters of the nutrient solution a. The upper space of the drainage tank 22 and the drainage port 27 formed in the bottom plate at the other end of the cultivation tank 12 are communicated by a drainage pipe 28. The nutrient solution circulation unit 24 has one end disposed at the bottom of the drainage tank 22 and the other end disposed in the upper space of the liquid storage tank 20, and the drainage tank 22 side of the return pipe 29. And a second submersible pump 30 provided at the end of the. By operating the first submersible pump 25, the nutrient solution a of the liquid storage tank 20 is supplied to the liquid storage space 11 from one end of the cultivation tank 12 through the supply pipe 26. Thereafter, the nutrient solution a flows through the liquid storage space 11 and flows into the drainage tank 22 through the drainage pipe 28 from the drainage port 27 at the other end. Thereafter, the nutrient solution a in the drainage tank 22 is returned to the liquid storage tank 20 through the return pipe 29 by the operation of the second submersible pump 30. Thus, the nutrient solution a circulates between the liquid storage tank 20, the cultivation tank 12, and the drainage tank 22 at 43 liters / minute. The height of the nutrient solution a in the liquid storage space 11 is about half that of the liquid storage space 11.

On the liquid surface of the nutrient solution a accumulated in the liquid storage space 11 of the cultivation tank 12, a planting float 13 having a length slightly shorter than the length of the cultivation tank 12 and having a width about half the width of the cultivation tank 12 floats. ing. The planting float 13 is made of expanded polystyrene. The planting float 13 is positioned at the intermediate portion in the width direction of the liquid storage space 11 by being covered from above with the resin film 14 for preventing water leakage.
As shown in FIG. 4, in the positioning method of the planting float 13, first, the intermediate portion in the width direction of the resin film 14 for preventing water leakage is directly placed on the planting float 13 immediately above the cultivation tank 12 (solid line in FIG. 4). Next, the resin film 14 for preventing leakage of water immediately below the planting float 13 is squeezed, and the entire planting float 13 is wrapped with the resin film 14 for preventing leakage (one-dot chain line in FIG. 4). Thereafter, the planting float 13 is moved directly below, and this is disposed in the intermediate portion in the width direction of the liquid storage space 11 of the cultivation tank 12. At this time, the liquid storage space 11 is divided into two left and right (its width direction) by the water leakage preventing resin film 14 (two-dot chain line in FIG. 4). Thereafter, by feeding the nutrient solution a to the cultivation tank 12, approximately the same amount of nutrient solution a flows into the liquid storage space 11 that is divided into left and right parts. At that time, narrowing of the resin film 14 for preventing water leakage just below the fixed planting float 13 is further increased by water pressure. As a result, due to the pressure of the nutrient solution a flowing through the liquid storage space 11, the fixed planting float 13 is placed on the intermediate surface in the width direction of the liquid storage space 11 on the liquid surface of the nutrient solution a via the water leakage preventing resin film 14. Positioned.

As shown in FIGS. 1, 3, and 5, the upper surface of the planting float 13 has a length that is substantially the same as the length of the planting float 13 and a width that is approximately twice the width of the planting float 13. A two-part water-absorbing sheet comprising the lower partial water-absorbing sheet 15A and the lower partial water-absorbing sheet 15A whose length is substantially the same as the length of the planting float 13 and whose width is 173% of the width of the planting float 13 15 is placed.
Here, as the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B, “Cook Up Kitchen Cloth” manufactured by Unicharm Corporation is adopted. The “cook-up kitchen cloth” includes an intermediate layer 33 containing pulp short fibers between the first surface layer 31 containing synthetic resin short fibers and the second surface layer 32 containing synthetic resin short fibers. It consists of a nonwoven fabric with a three-layer structure in which short fibers are entangled by the water jet method (FIG. 6). The first surface layer 31 is a nonwoven fabric made of a mixed fiber of 63 to 87% by weight of polyester short fibers and 13 to 37% by weight of rayon short fibers. The second surface layer 32 is a nonwoven fabric made of a mixed fiber of 60 to 80% by weight of polyester short fibers and 20 to 40% by weight of pulp short fibers. The intermediate layer 33 is a nonwoven fabric made of 100% by weight of pulverized pulp. If this water supply sheet | seat 15 is employ | adopted, the high sugar content of a tomato by stress control and the control of the yield can be aimed at. In addition, as the lower partial water absorbent sheet 15A, a laminate of a plurality of sheets may be adopted in summer and winter in order to prevent the sheet from drying.
As shown in FIGS. 1, 3, and 5, each plug seedling 16 of tomato has a soil attached to a pot root and does not contain rock wool. Each plug seedling 16 is wrapped in a sandwich state between the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B at a constant pitch in the length direction of the planting float 13.

Next, with reference to FIGS. 1-6, the hydroponic cultivation method of the tomato by the hydroponic cultivation apparatus 10 which concerns on Example 1 of this invention is demonstrated.
As shown in FIGS. 1, 3 and 5, first, a plurality of plug seedlings 16 are arranged at a constant pitch in the length direction of the planting float 13 and in a staggered pattern in the width direction of the planting float 13, Wrapping between the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B. At this time, both ends in the width direction of the lower partial water absorbent sheet 15 </ b> A are disposed below the liquid level of the nutrient solution a accumulated in the liquid storage space 11 of the cultivation tank 12. Accordingly, the lower partial water absorbent sheet 15A sucks up the nutrient solution a by capillary action, and supplies the nutrient solution a to the lower surface of each plug seedling 16 and the upper surface of each plug seedling 16 via the upper partial water absorbent sheet 15B.

  In that case, the width | variety of the upper part water absorption sheet | seat 15B is 20% shorter than the width | variety of the planting float 13 (FIG. 5). Specifically, when the upper partial water-absorbing sheet 15B is placed on the planting float 13, the gaps d (between the both ends in the width direction of the planting float 13 and both ends in the width direction of the upper partial water-absorbing sheet 15B, respectively. A few cm). Thus, since the upper partial water absorbent sheet 15B having a width shorter than that of the lower partial water absorbent sheet 15A is placed on the plug seedling 16, the tomato buds that germinate and grow are separated from the end in the width direction of the upper partial water absorbent sheet 15B and the lower part. It extends outward from the gap with the water absorbent sheet 15A. At that time, if the upper partial water-absorbing sheet 15B is longer than the width of the planting float 13, the upper partial water-absorbing sheet 15B hangs from the edge in the width direction of the planting float 13, so that the grown buds may be immersed in the nutrient solution a and rot. is there. Therefore, in Example 1, the width of the upper partial water absorbent sheet 15 </ b> B was made shorter than the width of the planting float 13. Thus, when the tomato buds extend outward from the gap between the widthwise end of the upper partial water absorbent sheet 15B and the widthwise end of the planting float 13, the end of the planting float 13 faces the bud downward. A guide to avoid stretching. As a result, there is no possibility that the tomato buds will be soaked in the nutrient solution a and rotten. Since the planting float 13 floats and sinks according to the height of the liquid level of the nutrient solution stored in the cultivation tank 12, the roots of the plug seedlings 16 can automatically respond to changes in the level of the nutrient solution, Management of the amount of nutrient solution in the cultivation tank 12 becomes easy.

Next, as shown in FIG. 2, the first submersible pump 25 of the liquid circulation means 19 is operated to supply the nutrient solution a accumulated in the liquid storage tank 20 to one end of the cultivation tank 12 from the supply pipe 26. Thus, the nutrient solution a flows through the liquid storage space 11 of the cultivation tank 12 and is discharged from the other end of the cultivation tank 12 to the drainage tank 22 through the drainage port 27 and the drainage pipe 28. Thereafter, the nutrient solution a accumulated in the drainage tank 22 is returned to the storage tank 20 through the return pipe 29 by the second submersible pump 30, and the nutrient solution a is stored in the storage tank 20, the cultivation tank 12, and the drainage tank 22. Circulate between.
As shown in FIGS. 1, 3 and 5, the nutrient solution a is sucked up from both ends in the width direction disposed below the liquid surface of the lower partial water absorbent sheet 15 </ b> A, and part of the nutrient liquid a is the lower partial water absorbent sheet The plug seedlings 16 on the fixed planting float 13 are supplied from the lower surfaces through 15A. On the other hand, the remaining portion of the nutrient solution a sucked up by the lower partial water absorbent sheet 15A is a contact portion between the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B (in particular, between the plug seedlings 16 of the upper partial water absorbent sheet 15B. From the portion) to the upper partial water absorbent sheet 15B and supplied to the upper surface of the plug seedling 16. Thus, since the plug seedling 16 is configured to be wrapped from the vertical direction by the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B, the nutrient solution a can be sufficiently supplied to the tomato seedlings.

Thus, since the cultivation tank 12 was manufactured from the polystyrene foam, weight reduction can be achieved and the installation of the apparatus at the site becomes easy, and the cost of the cultivation tank 12 can be reduced. Moreover, if the expanded polystyrene is adopted as the material of the cultivation tank 12, the cultivation tank 12 becomes weaker and more easily damaged than those made of unfoamed hard synthetic resin. Therefore, the wall for forming the liquid storage space 11 of the cultivation tank 12 is covered with a resin film 14 for preventing water leakage from the inside. Thereby, the nutrient solution leak at the time of the failure | damage of the cultivation tank 12 can be prevented.
In addition, since the plug seedling 16 that does not contain rock wool is adopted as the water retention medium, disposal of used rock wool as industrial waste, which was necessary in the case of the conventional apparatus, is not required, and the disposal cost is not incurred.

Furthermore, in the case of the hydroponic cultivation apparatus 10 combining such a submerged hydroponic method and a capillary hydroponic method, in the conventional apparatus, the water permeability is blocked so that the root does not extend to the nutrient solution a. Although a root-proof sheet was necessary, the water-permeable sheet 15 is not used here in a disposable manner, and therefore a water-permeable root-proof sheet is not necessary. Moreover, since the resin film 14 for preventing water leakage and the water supply sheet 15 are disposable, there is no need to perform sterilization treatment such as disinfection and drying of the entire apparatus every time the cultivated plant is cultivated as in the case of the conventional apparatus. The hydroponic cultivation apparatus 10 can be reused. Even if bacteria have propagated in the cultivation tank 12, since the cultivation tank 12 is made of low-cost foamed polystyrene, compared to the case of the conventional apparatus having a rigid plastic cultivation tank even if it is disposable including the cultivation tank 12, Costs for reuse can be reduced.
Further, as the lower partial water absorbent sheet 15A and the upper partial water absorbent sheet 15B, an intermediate layer 33 containing pulp short fibers is provided between the first surface layer 31 containing the synthetic resin short fibers and the second surface layer 32, respectively. Since the intervening three-layered nonwoven fabric is adopted, a large amount of the nutrient solution a sucked up from the liquid storage space 11 can be retained in these three nonwoven fabric layers, particularly the intermediate layer 33 containing pulp short fibers, and the plug The nutrient solution a can be sufficiently supplied to the seedling 16. In addition, since the first surface layer 31 and the second surface layer 32 each contain synthetic resin short fibers, even if the water absorbent sheet 15 is immersed in the nutrient solution a, it maintains its shape as a sheet, and melts or tears. Hateful. In addition, when these three nonwoven fabric layers are integrated, the respective short fibers are entangled so that the conventional short fibers are spot-bonded with an adhesive, like a water absorbent sheet 15 made of a nonwoven fabric. There is no risk that the additive contained will inhibit the growth of the cultured plant or have a detrimental effect on the person eating it.

Further, the first surface layer 31 is a non-woven fabric made of a mixed fiber of 63 to 87% by weight of polyester short fibers and 13 to 37% by weight of rayon short fibers, and the second surface layer 32 is 60 to 80% by weight of polyester short fibers. % And a short fiber of 20 to 40% by weight, and the intermediate layer 33 is a non-woven fabric of 100% by weight of pulverized pulp. A water absorbent sheet 15 having water absorption is obtained. That is, a large amount of nutrient solution can be retained in the three nonwoven fabric layers 31 to 33, particularly the intermediate layer 33 made of pulverized pulp, and the nutrient solution can be sufficiently supplied to the plug seedling 16. In addition, since the first surface layer 31 and the second surface layer 32 each contain polyester short fibers having high hardness among the synthetic resin fibers, the shape as a sheet is maintained even when the water absorbent sheet 15 is immersed in the nutrient solution. , Hard to melt or tear.
Moreover, since the 1st surface layer 31 and the 2nd surface layer 32 contain the polyester short fiber which improves the shape retention property of the water absorption sheet 15, the width direction of the fixed planting float 13 among the lower side partial water absorption sheets 15A. It is difficult for the lower part water absorbent sheet 15A to be set at the contact portions with both side edges. As a result, the nutrient solution can be smoothly sucked upward from the contact portion of the lower partial water absorbent sheet 15A.

  The present invention is useful for growing cultured plants such as tomatoes, cucumbers, strawberries, lettuce, green onions and melons that can be hydroponically cultivated.

10 Hydroponics equipment,
11 Liquid storage space,
12 Cultivation tank,
13 Planting float,
14 Resin film for preventing water leakage,
15 water absorption sheet,
15A Lower side water absorbent sheet,
15B Upper part water absorption sheet,
16 Plug seedling,
31 first surface layer;
32 second surface layer,
33 Middle layer,
a Nutrient solution.

Claims (3)

Cultivation tank made of foamed synthetic resin with a nutrient solution storage space inside,
A planting float floating on the liquid level of the nutrient solution stored in the liquid storage space;
A resin film for preventing leakage of water, which covers the forming wall of the liquid storage space of the cultivation tank from the inside and positions the fixed planting float in the middle in the width direction of the liquid storage space by covering the fixed planting float from above. ,
A water-absorbing sheet placed on the planting float and having an end disposed below the surface of the nutrient solution;
It does not contain rock wool and includes a plug seedling of a cultivated plant placed on the water absorbing sheet placed on the upper surface of the fixed plant float,
The water absorbing sheet is
An end portion is disposed below the liquid level of the nutrient solution, and a lower partial water absorbent sheet on which the plug seedling is placed;
The upper part water-absorbing sheet that covers the plug seedling from above,
The lower partial water absorbent sheet and the upper partial water absorbent sheet are:
Three layers in which an intermediate layer containing pulp short fibers is arranged between the first surface layer containing synthetic resin short fibers and the second surface layer containing synthetic resin short fibers so that the respective short fibers are entangled. Hydroponic cultivation device made of non-woven fabric. The first surface layer is a non-woven fabric composed of a mixed fiber of 63 to 87% by weight of polyester staple fibers and 13 to 37% by weight of rayon staple fibers,
The second surface layer is a non-woven fabric composed of a mixed fiber of polyester short fibers 60 to 80% by weight and pulp short fibers 20 to 40% by weight,
The hydroponic cultivation apparatus according to claim 1, wherein the intermediate layer is a nonwoven fabric made of 100% by weight of pulverized pulp.   The hydroponic cultivation apparatus according to claim 1 or 2, wherein a width of the upper partial water-absorbing sheet is shorter than a width of the planting float.

Images