JP7016142B2 - Hydroponics equipment and method - Google Patents

Description

The present invention relates to an apparatus for hydroponically cultivating plants, particularly vegetables, and a method for hydroponics.

Conventionally, in plant cultivation, a technique of irradiating plant seedlings with artificial light to promote seedling raising has been adopted. By promoting the growth of plants, the cultivation period can be shortened and the number of harvests in the same place can be increased. Moreover, even in the same cultivation period, if the plant can be grown larger, the yield can be increased.

As a plant cultivation method using artificial light irradiation, for example, Patent Document 1 discloses a method of obtaining a plant growth promoting effect by alternately irradiating red light illumination light and blue light illumination light. This irradiation device has a light irradiation unit that irradiates a plant with red light illumination light and a blue light illumination light, a step of controlling the light irradiation unit to irradiate the plant with red light illumination light, and irradiates the plant with blue light illumination light. The plant is grown by a plant cultivation device equipped with a control unit for performing the steps to be performed independently within a certain period of time.

In many cases, the amount of light from the light source was increased too much in an attempt to secure a certain amount of yield, and if the conditions were continued, problems such as leaf burning occurred and the yield could not be increased.
In the technique of Patent Document 1, this problem is avoided by alternately irradiating red light and blue light under the condition of an illuminance of 1000 lux (lp), and 6.8 g of fresh weight of the above-ground part is obtained by growing lettuce on the 21st. ing.

Further, in such a plant production system, since artificial lighting, air conditioning, etc. are used, there is a problem that energy consumption is larger than that of normal cultivation. In particular, in the case of such a closed plant production system, the internal environment cannot be maintained when the supply of electric energy is cut off.
Therefore, for example, Patent Document 2 is provided with a private power generation device so as to be able to constantly supply electric power to a plant production system, and heat exchange pipes are installed on the floor and ceiling to make the temperature distribution uniform and uniform. A device capable of various cultivation has been proposed.

In the technology of Patent Document 2, consideration is given to electrical energy and temperature distribution, and although there is a certain effect in obtaining a stable harvest, running costs are used because light and air conditioning are used in the plant production system. Is larger than that of conventional agriculture. High productivity is required to clear this point.

Patent Document 3 discloses a device in which a part of a root is exposed to the outside air by intermittently supplying and draining water, and the root growth is promoted by the stimulation.
Patent Document 4 proposes a system that integrates a fish and shellfish breeding system and hydroponics, and uses a bell-shaped siphon to circulate cultivated nutrient solution while draining water from a plurality of cultivation shelves to the breeding shelves. ing.

In the device of Patent Document 3, it was discovered that intermittent water supply, that is, the effect of promoting root growth by periodically feeding a drought state and causing rapid growth of above-ground parts (leaves and stems) by autocrine of growth hormone. Although the cultivation period is 30 days and a large yield of 200 g is achieved, there is a problem that the cultivation period needs to be further shortened in consideration of profitability.
In the device of Patent Document 4, a strong water flow is generated by collectively draining water from each cultivation shelf using a bell-shaped siphon, and air is contained by the water flow when it is supplied to the fish and shellfish breeding tank. It also aims to make it.

International publication number WO2013 / 021952 International publication number WO2007 / 050862 JP 2015-209423 JP 2017-139980

As mentioned above, hydroponics is cultivated in an indoor environment, so stable production that is not affected by the weather such as sunshine, cold damage, and flood damage is possible, and pesticides are not required because it is not affected by insect damage. However, it reduces the huge cost required for equipment such as cultivation shelves, air conditioning, air volume control, water circulation, temperature, air volume, light volume, water volume control and its operation, and far exceeds the yield of conventional agriculture. There is a problem that the yield must be secured in a short period of time.

The hydroponic cultivation apparatus according to the present invention has a nursery bed having a dome-shaped downward concave depression at the lower part and a slit at the upper part extending from the upper surface to the ceiling of the depression, and a cultivation board accommodating a plurality of the nursery beds. A multi-tiered cultivation rack consisting of a concave cultivation gutter with an upwardly concave cross section on which the cultivation board is placed on the upper end, and a cultivation tub, each of which is filled with water and drought. A siphon and an overflow pipe that are sequentially changed from the upper stage to the lower stage are provided, and when the water level reaches the full level after reaching the upper limit level of the overflow pipe, the siphon or the overflow pipe moves the nutrient water to the next lower cultivation gutter. Then, the cycle of full water is set to 30 minutes, and the state of full water and drought is repeated, and by changing the set position of the siphon and the overflow pipe, the drought level, which is the water level at the time of drought, is automatically adjusted according to the growth of the root. It is characterized by being changed to .

The hydroponic cultivation method according to the present invention includes a nursery bed having a dome-shaped downward concave depression at the lower part and a slit at the upper part extending from the upper surface to the ceiling of the depression, and a cultivation board accommodating a plurality of the nursery beds. The cultivation board is placed on the upper end thereof, and the cultivation shelves are composed of a concave cultivation siphon having an upwardly facing cross section and a cultivation shelf , and each of the cultivation tubs is filled with water and drought. Hydroponic cultivation is provided with siphons and overflow pipes that move in order from the top to the bottom of the cultivation trough, and a lighting device that can control the ON state and OFF state is provided above and / or side of each cultivation shelf. In the hydroponic cultivation method of the device, when the full water level is reached after reaching the upper limit level of the overflow pipe, the water is transferred to the cultivation trough one below by the siphon or the overflow pipe, and the full water cycle is 30 minutes. By repeating the state of full water and drought, and changing the setting position of the siphon and the overflow pipe, the drought level, which is the water level at the time of drought, is automatically changed according to the growth of the root, and the lighting device of the lighting device. The ratio of the ON time to the OFF time is 2: 1 to 4: 1, and the cycle consisting of the ON time and the OFF time of the lighting device is set to a minimum of 30 minutes to a maximum of 24 hours for operation . ..

Since the hydroponic cultivation apparatus according to the present invention is provided with a nursery bed having a dome-shaped downward concave depression, the roots can be in an open state in contact with the air from an early stage of seedling growth, and at an early stage. Therefore, when switching between full water and drought, the roots are well rocked inside the depression by the water flow, which promotes root growth, and as a result, the abrupt above-ground parts (leaves and stems) due to the self-secretion of growth hormone. It has the effect of accelerating the start of growth.

Further, the hydroponic cultivation method according to the present invention is provided with a power supply control unit capable of setting the ratio of the ON time and the OFF time of the lighting to 2: 1 to 4: 1, and in particular, the cycle of the ON time + OFF time is shortened. Even in this case, the effect of promoting the growth of leaves on the cultivation shelf after the 6th cycle appears, and the growth period is shortened. It is possible to shorten the number of harvest days and reduce the power consumption associated with it. For example, when the ratio of the ON time to the OFF time is set to 3: 1, there is an effect that the same growth can be promoted even if the power consumption is reduced to 3/4.

It is a figure which shows the structure of the hydroponic cultivation apparatus using a siphon. The shape of a conventional sponge-like cultivation pad used in a hydroponic cultivation device is shown. The shape of the sponge-like cultivation pad of the present invention used in a hydroponic cultivation apparatus is shown. It is a figure which shows the water level of the drought of the cultivation shelf. It is a figure which shows the water level of the full water of a cultivation shelf. It is a graph which shows the change of the water level in each cultivation shelf. It is a graph showing the weight change of the cultivated product by the conventional hydroponic cultivation method, A is the case by the general conventional method, and B is the case by the improved conventional method. It is a graph showing the weight change of the cultivated product by the hydroponic cultivation method by this invention, B is the improved conventional method, and C, D, E are the case by this invention. It is a detailed enlarged view of the lower left part of FIG. It is a photograph comparing the root elongation of the cultivation method B using the conventional cultivation pad and the root elongation of the cultivation method C using the cultivation pad having a downward concave portion on the bottom surface.

[Conventional Example A]
Referring to FIG. 1, it is a figure showing the structure of a hydroponic cultivation apparatus using a siphon, in which a cultivation board 13 (not shown) having a substantially rectangular top view and a light source provided above the cultivation board 13 (not shown). (Not shown) and a cultivation shelf 5 consisting of a cultivation gutter 3 provided with an overflow pipe 1 and a siphon 2 provided below or to the side of the cultivation board 13 (lower in the figure) are stacked in two or more stages. It consists of a plurality of cultivation shelves (in the figure, four-tiered cultivation shelves including cultivation gutters 3a, 3b, 3c, and 3d, respectively).

The water supply / drainage channel is provided below the cultivation board 13 along the long side of the cultivation board 13.

This hydroponic cultivation device is provided with a water amount control mechanism that controls whether or not the drainage of the cultivation gutter 3 in a certain stage flows as water supply for the cultivation gutter 3 in the lower stage.

The uppermost cultivation gutter 3 is replenished with nutrient solution using a pump from the lowermost cultivation shelf 3 or from a nutrient solution storage tank installed outside.

The water amount control mechanism can embody both a full state in which water is sufficiently supplied to the cultivation gutter 3 in each stage and a drought state in which a small amount of water is supplied or no water is supplied.

The light source has an external control power supply (not shown), and can switch between an ON (bright) state and an OFF (dark) state and control the cycle thereof.
Here, the ON (bright) state refers to a lighting state of, for example, about 5000 lux (lx), while the OFF (dark) state refers to a lighting state to which the cultivated plant does not substantially photosynthesize, for example, about 2500 lux. It includes a state that is not necessarily dark for human beings.

The seeds grow on the sowing rack for 4 days, and the germinated seedlings are transplanted to the nursery 11 of the hydroponic cultivation device on the 5th day.

The seedling 10 holds the seeds and stems by the slit 14 at the upper part of the nursery 11, so that the root 12 can hang down.

As shown in FIG. 2A, the nursery 11 is formed of, for example, a sponge having a top view cross cut and a flat bottom surface.
The nursery 11 has a thickness of, for example, 30 mm, and this thickness is necessary for stably fixing the seedlings even when the leafy vegetables grow large, for example.

As shown in FIG. 2 (b), the nursery 11 is fitted into a hole provided in the cultivation board 13.
As shown in FIG. 4, the cultivation board 13 into which the nursery 11 is fitted is placed on the open upper end portion of the cultivation gutter 5.

[Conventional Example B]
In the above-mentioned conventional example A, as shown in FIG. 5, the nourishing water is maintained as it is when the full water level 31 that fills all the cultivation gutters 3 is reached.

On the other hand, in the improved conventional example B, referring to FIG. 5, for example, when the water supply of the uppermost cultivation gutter 3 reaches the full water level 31 after reaching the upper limit level of the overflow pipe 1, the siphon 2 or the overflow pipe is used. Move to the next lower cultivation gutter 3 by G1.

Then, referring to FIG. 4, the nutrient solution is drained to the lower limit level of drought level 30.

As a result of using the cultivation gutter 3 capable of periodically controlling the drought / drought water level, referring to FIG. 6, the full / drought levels of the cultivation gutters 3a, 3b, 3c, and 3d are different. It changes in order like 40, 41, 42, 43.

The drought level 30 of the cultivation gutter 3 is, for example, 20 mm, and the full water level is 70 mm.
Further, the full water level time is, for example, 5 minutes, and the repetition cycle of the full water level is, for example, 30 minutes.

According to Patent Document 3, root growth is stable without causing root rot as compared with the case where oxygen is supplied to the roots by repeating such a full state and a drought state and the roots are kept in a full state. Can grow.

In particular, the roots are also shaken by the wave motion caused by the supply of nutrient water when switching from a drought state to a full state, and oxygen is sufficiently supplied.

Even in the conventional example A, the water is exchanged and circulated for maintenance, but the control is not performed so as to change the water level so as to periodically change the full water level 31 to the drought level 30.

Referring to FIG. 7, it is a graph comparing the weight per share of the conventional example A and the improved conventional example B. On the horizontal axis, the sowing date is the first day, and the seeding day is moved to the cultivation shelf on the fifth day.

The cultivation environment is provided with an appropriate amount of carbon dioxide and an appropriate amount of liquid fertilizer.
Except for the presence or absence of the above-mentioned full / dry cycle, the lighting conditions, the amount of carbon dioxide, the nutrient solution containing liquid fertilizer, and the like are all the same as in the conventional example A.

Referring to FIG. 7, conventional example B and conventional example A are compared. As a result of promoting the growth of root 12 by repeating the drought-full cycle, a large yield can be obtained early. It shows that it is.

[Example C]
Referring to FIG. 3, in the present embodiment C, unlike the above-mentioned conventional example A and the improved conventional example B, the nursery 11 has a dome-shaped downward recess 20 and the slit 14 at the upper part of the recess 20. The seeds and stems of the buds 10 are held so that the roots 12 hang down in the recesses 20.
In Example C, specifically, as shown in FIG. 5, a 30 mm thick sponge nursery 11 having a dome-shaped downward recess 20 on the bottom surface was used. The vertical length of the slit is, for example, 10 mm.

The drought level 30 was set to 27 mm. The drought level can be changed by the setting position of the siphon 2, but it is also possible to automatically change the height as the root grows.

The same conditions as in Conventional Example B were used for all other conditions such as lighting, carbon dioxide conditions, and nutrient solution conditions.

In order for the stems and leaves of the leaves to grow on the upper surface of the nursery 11, it is necessary to set the germinated seedlings on the upper surface of the nursery 11, but in the case of this Example C, the nursery 11 having a dome-shaped downward recess 20 Then, the root 12 only grows through the slit 14 having a length of, for example, 10 mm, and is rapidly exited below the nursery 11.
On the other hand, in the case of the improved conventional example B, it takes time for the root 12 to grow through the slit 14 having a length of 30 mm corresponding to the thickness of the nursery 11, for example, and to come out below the nursery 11.
Referring to FIG. 8, the number of days that Example C can harvest 200 g per share can be shortened by about 2 days as compared with Conventional Example B.

The reason for this is in the case of Example C.
(I) In addition to the fact that the effects of the full / dry cycle of supplying oxygen to the roots in a drought state and rocking the roots in a full state can be obtained more quickly than in the case of Example B.
(Ii) The roots are stimulated by swinging inside the dome-shaped recess 20, the root tissue is activated, and the root growth is promoted, so that the self-secretion of growth hormone becomes faster. The rapid start of growth of the above-ground parts (leaves and stems) due to the secretion of growth hormone is accelerated.

Looking at FIG. 8 in detail, it can be seen that in Example C, the rapid growth start of the above-ground part (leaves and stems) is earlier than in Conventional Example B, and the slope of the growth curve is large. .. From this, it can be seen that the use of the nursery 11 having the dome-shaped recess 20 is effective in accelerating the growth of the root 12 and subsequently increasing the total weight of the root 12.

Referring to FIG. 9, it is a photograph comparing how much the root growth is different between the conventional example B and the example C. By using the nursery 11 having the recess 20, the root growth of Example C was better by about 20% in the cultivation period of one week. It is considered that this fast root growth contributes to the growth of the fast aboveground parts (leaves and stems).

[Example D]
Through the above-mentioned conventional example A, improved conventional example B, and embodiment C of the present application, a fluorescent lamp was used for illumination, the lighting was always ON (bright), and the amount of light was 5,500 lux (lx).
In this Example D, as described above, in Example C, the lighting was always ON, whereas the ON (bright) / OFF (dark) cycle was introduced.
The indoor environment has an appropriate amount of carbon dioxide, the nutrient solution has an appropriate amount of liquid fertilizer, and all other conditions such as the shape of the nursery 11 to be used and the drought level 30 are the same as in Example C. be.

The duty of lighting time was fixed at 3: 1 and a fluorescent lamp was used as the illumination light source as well, but as a result of examination, it is optimal to increase the amount of light slightly to 6,000 lux (lp). found. Considering the ON duty even with this amount of light, the power consumption is lower than the power consumption in Example C.

It was found that when the entire cycle of ON time + OFF time is 24 hours, that is, one day, there is an effect of promoting leaf growth as compared with the case of always ON. For example, the average value of the seedling height 15 days after sowing of Korean lettuce was 10 cm in the case of Example C, whereas it was 12.5 cm in this Example D.
Examination of the details of the growth curve revealed that the effect of promoting growth by blinking the lighting appeared from the 6th day, that is, from the 6th cycle. That is, it was found that giving a cycle of ON time and OFF time is important as a starting point for promoting leaf growth.

With reference to the growth curve of Example D in FIG. 8, the effect becomes remarkable after the 6th day after moving to the cultivation shelf, that is, the 11th day after sowing, and the number of days when 200 g per plant can be harvested is carried out. It is at least one day ahead of that of Example C.

[Example E]
Next, if the growth can be promoted by giving a light-dark cycle even if it is a short cycle, it is thought that the cultivation promotion effect can be obtained from an earlier cultivation day, and the irradiation cycle is set to 1 hour without changing other conditions. After shortening to, the increase in weight was also large at the 6th cycle, that is, at the 6th hour. From this result, if a constant (6 times) number of blinks is given, there is an effect of light-dark cycle regardless of the cycle, and the starting point where leaf growth is promoted by irradiating light with a short cycle is shortened. It turned out that it can be transformed.
With reference to the growth curve of Example E in FIG. 8, the effect becomes remarkable from the first day after moving to the cultivation shelf, that is, from the sixth day after sowing, and the number of days when 200 g per plant can be harvested. Seen, it is at least 3 days ahead of that of Example D.

Referring to FIG. 9, it is a detailed enlarged view of the lower left portion in FIG. 8, and when the ON + OFF cycle is one day (D) as compared with the case of always ON (Example C), the tenth day after sowing. That is, the weight increase becomes remarkable after the 6th day after moving to the cultivation shelf (6 cycles of light and dark cycles), whereas when the ON + OFF cycle is 1 hour (E), the 6th day after sowing, That is, it can be seen that the weight increase becomes remarkable as early as the first day after moving to the cultivation shelf (only 6 cycles are spent in the light-dark cycle).

In the case of a shorter cycle of 30 minutes or less, the weight increase in the 6th cycle was not stable, so the minimum value of the cycle is 30 minutes, but the 1-hour cycle (ON time 45 minutes, OFF time 15 minutes). ) Is considered to be the most practical and effective means of irradiating light. On the other hand, in order to obtain the effect of 6 cycles in one day and night, a cycle of about 4 hours is required, and as a result, the maximum value of the cycle is 5 hours.

The hydroponic cultivation apparatus according to the present invention can be produced on all scales from small-scale production to large-scale production. Large-scale production is highly efficient and suitable for stable production, and small-scale production is suitable not only for trial production but also for direct use at consumption sites, restaurants, homes, and sales sites. Suitable. In addition, by combining large and small scales, it is possible to provide end users with vegetables and other plants that are prone to deterioration while ensuring efficient distribution.

1 Overflow pipe 2 Siphon 3,3a, 3b, 3c, 3d Cultivation gutter 5 Cultivation shelf 10 Bud 11 Seedbed 12 Root 13 Cultivation board 14 Slit 20 Recess 30 Drought level (water level)
31 Full water level (water level)
40 Change in water level of the first stage (top level) cultivation gutter 41 Change in water level of the second stage cultivation gutter 42 Change in water level of the third stage cultivation gutter 43 Change in water level of the fourth stage (lowest stage) cultivation gutter

Claims (4)

A nursery with a dome-shaped downward concave depression in the lower part and a slit in the upper part extending from the upper surface to the ceiling of the depression, a cultivation board accommodating a plurality of the nursery beds, and the cultivation board placed on the upper end. A cultivation gutter with a concave cross section facing upward, a multi-tiered cultivation shelf consisting of a cultivation rack, and a cultivation shelf.
Each of the cultivation tubs is provided with a siphon and an overflow pipe that change the state of fullness and drought in order from the upper stage to the lower stage of the cultivation gutter, and when the upper limit level of the overflow pipe is reached, the full water level is reached. , The siphon or the overflow pipe moves the nutrient water to the next lower cultivation gutter, the cycle of full water is set to 30 minutes, the state of full water and drought is repeated, and the setting position of the siphon and the overflow pipe is changed. A hydroponic cultivation device characterized in that the drought level is automatically changed according to the growth of roots . Each cultivation shelf has lighting above and / or to the side of each shelf, and the lighting can be controlled between the ON state and the OFF state.
The ratio of the ON time to the OFF time of the lighting is 2: 1 to 4: 1, and the cycle consisting of the sum of the ON time + the OFF time of the lighting is set from a maximum of 24 hours to a minimum of 30 minutes. The hydroponic cultivation apparatus according to claim 1. A nursery with a dome-shaped downward concave depression at the bottom and a slit at the top that reaches the ceiling of the depression, a cultivation board that accommodates a plurality of the nurseries, and the cultivation board placed on the upper end. It is composed of a cultivation gutter with a concave shape with an upward cross section and a cultivation shelf consisting of multiple stages. It is a hydroponic cultivation method of a hydroponic cultivation device in which a transition siphon and an overflow pipe are provided, and a lighting device capable of controlling an ON state and an OFF state is provided above and / or to the side of each cultivation shelf. hand,
When the full water level is reached after reaching the upper limit level of the overflow pipe, the nourishing water is moved to the cultivation gutter one level below by the siphon or the overflow pipe, and the full water cycle is set to 30 minutes to check the full and drought states. By repeatedly changing the setting positions of the siphon and the overflow pipe, the drought level, which is the water level at the time of drought, is automatically changed according to the growth of the roots.
The ratio of the ON time to the OFF time of the lighting device is 2: 1 to 4: 1, and the cycle consisting of the ON time and the OFF time of the lighting device is set to a minimum of 30 minutes to a maximum of 24 hours for operation. A hydroponic cultivation method characterized by. The hydroponics according to claim 3 , wherein the ratio of the ON time to the OFF time of the lighting is set to 3: 1 and the cycle consisting of the sum of the ON time and the OFF time of the lighting is controlled to be 1 hour. How to control the cultivation equipment.

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