AU2016323373B2

AU2016323373B2 - Culture device and culture method

Info

Publication number: AU2016323373B2
Application number: AU2016323373A
Authority: AU
Inventors: Junya Fuse; Norihiro Higashi
Original assignee: Mitsubishi Chemical Aqua Solutions Co Ltd
Current assignee: Mitsubishi Chemical Aqua Solutions Co Ltd
Priority date: 2015-09-17
Filing date: 2016-06-21
Publication date: 2021-01-21
Anticipated expiration: 2036-06-21
Also published as: WO2017047186A1; JP6056929B1; CN108024510B; CN108024510A; JP2017055720A; AU2016323373A1

Abstract

Provided is a culture device in which air can be uniformly circulated to each seedling-raising shelf and the environment of each seedling-raising shelf can be made uniform even if the number of installed air conditioning devices is small; also provided is a culture method using this culture device. The culture device includes: a building structure 1 that constitutes a closed space; an air conditioning device 9 that is installed in a ceiling inside the building structure; and multi-level shelf-type plant-raising devices 3-8 that are disposed in the building structure 1 and that have open front surfaces. The culture device is characterized in that, in plan view, an air inlet port of the air conditioning device is positioned to the front of the front surfaces of the multi-level shelf-type plant-raising devices 3-8, and an air outlet port 9f of the air conditioning device is positioned to the rear of the front surfaces.

Description

DESCRIPTION

Title of Invention: PLANT CULTIVATION APPARATUS AND PLANT

CULTIVATION METHOD

Technical Field

[0001] The present invention relates to a plant

cultivation apparatus such as a seedling cultivation

apparatus, and to a plant cultivation method using the plant

cultivation apparatus.

Background Art

[0002] Hitherto, cultivation in plant factories has been

widely put into

practice as a method of growing fruit vegetables, leafy

vegetables, etc. A capability of promoting uniform plant

growth is one feature of the cultivation in plant factories,

and various methods are employed to realize the uniform

plant growth. For example, Japanese Unexamined Patent

Application Publication No. 2006-294595 discloses a method

of uniformly applying light with use of artificial lighting

devices and reflectors. In the cultivation in a closed type

plant factory using artificial light, making lighting

conditions uniform is important, but making air temperatures

condition uniform is also important in order to realize

uniform growth of transplants. The disclosed method is not

sufficient in the point of making the air temperatures

10053881_1 (GHMaters) P108301.AU condition uniform.

[00031 As improved versions of the above-described method,

for example, International Publication W02004/026023 and

Japanese Patent Publication 2014-233231 A disclose methods

of providing uniform air circulation paths to all

cultivation shelves in a closed type plant factory and

realizing uniform air condition in all the shelves by

employing many air-conditioning units. The air condition of

the cultivation shelves can be kept uniform by those methods.

However, those methods have problems that the many air

conditioning units are needed, control of the individual

air-conditioning units is complicated, and that the

equipment cost is increased.

[0004] Patent Literature 1: Japanese Patent Publication

2006-294595A

Patent Literature 2: W02004/026023

Patent Literature 3: Japanese Patent Publication

2014-233231A

Advantage and Summary of Invention

[00051 Advantageously, the present invention may provide a

plant cultivation apparatus in which air can be uniformly

circulated to each cultivation rack and the air condition of

each cultivation rack can be made uniform even if the number

of installed air-conditioning unit is small; and a plant

cultivating method using this plant cultivation apparatus.

16758879_1 (GHMatters) P108301.AU

[0006] The present invention provides a plant cultivation

apparatus comprising: a structure that defines a closed

space; at least one air-conditioning unit installed in the

structure at a ceiling; and a growth module arranged in the

structure and opened at a front surface, the growth module

including cultivation racks arranged in multiple stages in

an up-down direction to form cultivating spaces, wherein,

when viewing the cultivation apparatus in plan, an intake

opening of the air-conditioning unit is positioned forward

of the front surface of the growth module, and a blow-off

opening of the air-conditioning unit is positioned in

alignment with the front surface or rearward of the front

surface.

[0007] The present invention provides a plant cultivating

method using this plant cultivation apparatus.

[0008] In one embodiment of the present invention, the

growth module includes at least one artificial lighting

device, and a ratio Wb/Wa of a total cooling capacity (Wb)

of all the air-conditioning units to a total power

consumption (Wa) of all the lighting devices is not less

than 1 and not more than 5.

[0009] In one embodiment of the present invention, the

growth module is disposed in plural numbers in two rows,

each including a plurality of the growth modules arrayed

with their open front surfaces oriented in the same

10053881_1 (GHMaters) P108301.AU direction, such that the open front surfaces of the growth modules in the two rows are opposed to each other, and the air-conditioning unit is disposed at the ceiling between the two rows.

Advantageous Effects of Invention

[0010] According to the present invention, since the blow

off opening of the air-conditioning unit is positioned

rearward of the front surface of the growth module and the

intake opening of the air-conditioning unit is positioned

forward of the front surface of the growth module, air

warmed up while passing through the growth module and air

cooled down by the air-conditioning unit can be caused to

flow into the front side of the growth module in a state

mixed together. As a result, the air flowing into the front

side of the growth module becomes air having a uniform

temperature, and is then flow into the growth module.

[0011] Preferably, the growth module is disposed in plural

numbers in two rows, each including a plurality of the

growth modules arrayed with their open front surfaces

oriented in the same direction, such that the open front

surfaces of the growth modules in the two rows are opposed

to each other, and the air-conditioning unit is disposed at

the ceiling between the two rows. With the above

arrangement, the air warmed up while passing through the

growth modules and the air cooled down by the air

10053881_1 (GHMaters) P108301.AU conditioning unit can be caused to flow into the front side of the growth modules in a state mixed together, and the mixed air can be more easily taken, in a uniform state, into the growth modules of which open front surfaces are opposed to each other.

Brief Description of Drawings

[0012] Figs. la and lb are horizontal sectional views of a

plant cultivation apparatus according to an embodiment.

Fig. 2a is a sectional view taken along a line IIa-IIa

in Fig. la. Fig. 2b is a sectional view taken along a line

IIb-IIb in Fig. la.

Fig. 3 is a front view of the plant growth module of

multistage rack type according to the embodiment.

Fig. 4 is a sectional view taken along a line IV-IV in

Fig. 3.

Fig. 5 is a plan view of a tray used in the plant

cultivation apparatus of multistage rack type according to

the embodiment.

Fig. 6 is a perspective view of the tray of Fig. 5.

Fig. 7 is a sectional view taken along a line VII-VII

in Fig. 5.

Fig. 8 is a bottom view of an artificial lighting

device.

Fig. 9 is a sectional view taken along a line IX-IX in

Fig. 8.

10053881_1 (GHMaters) P108301.AU

Fig. 10 is a sectional view of a tray used in a plant

cultivation apparatus of multistage rack type according to

another embodiment.

Fig. 11a is a vertical sectional view of a plant

cultivation apparatus according to an embodiment. Fig.llb

is a sectional view taken along a line XIb-XIb in Fig.lla.

Preferred Embodiments of the Invention

[0013] In one embodiment of the present invention, a plant

cultivation apparatus includes at least one air-conditioning

unit that controls environments in a closed space, and a

growth module that is opened at a front surface. In the

growth module, plant cultivation racks are arranged in

multiple stages in an up-down direction to form cultivation

spaces. An intake opening of the air-conditioning unit is

positioned forward of the front surface of the growth module

when viewing the plant cultivation apparatus in plan.

Furthermore, a blow-off opening of the air-conditioning unit

is positioned in alignment with the front surface or

rearward of the front surface of the growth module.

[0014] A preferred embodiment of the plant cultivation

apparatus will be described with reference to Figs. la and

lb to Fig. 10. As illustrated in Figs. la, lb, 2a and 2b, a

plurality (six in a illustrated example) of multistage typed

plant cultivation shelves (growth modules) 3 to 8 each

having a box shape are installed in a room of a closed

10053881_1 (GHMaters) P108301.AU structure 1, which is surrounded by heat-insulating wall surfaces and is completely light-shielded. The room of the structure 1 is rectangular when viewed in plan, and a door 2 is provided in one wall surface li extending in a widthwise direction. Figs. la and lb illustrate cross-sections taken along lines Ia-Ia and Ib-Ib in Fig. 2b, respectively.

[0015] In this embodiment, the three multistage typed

plant cultivation shelves 3 to 5 are arranged in line with

their open front surfaces facing in the same direction, and

the three multistage shelf type plant cultivation

apparatuses 6 to 8 are arranged in line with their open

front surfaces facing in the same direction. Thus, two rows

of the multistage shelf type plant cultivation apparatuses

are arranged in the room with their open front surfaces

opposing to each other. In the following, a direction in

which the rows of the multistage shelf type plant

cultivation apparatuses 3 to 5 and 6 to 8 extend (i.e., a

lengthwise direction of the room) is called a Y-direction,

and the widthwise direction of the room (i.e., a direction

in which the multistage typed plant cultivation shelves 3 to

and the multistage typed plant cultivation shelves 6 to 8

are opposed to each other) is called an X-direction

depending on cases. A space A allowing one or more workers

to perform work is formed between the two rows of the

multistage typed plant cultivation shelves 3 to 5 and 6 to 8.

10053881_1 (GHMaters) P108301.AU

A space B having a width of about 50 to 500 mm is formed

between lengthwise wall surfaces lj, 1k of the room and rear

surfaces of the multistage typed plant cultivation shelves 3

to 8, thus forming a path for air having passed through the

multistage typed plant cultivation shelves 3 to 8.

[0016] Respective one ends of the rows of the multistage

typed plant cultivation shelves 3 to 5 and 6 to 8 are in

contact with a structure wall surface lh on the opposite

side to the door 2. The respective other ends of the rows

of the multistage typed plant cultivation shelves 3 to 5 and

6 to 8 are slightly apart from the wall surface li on the

same side as the door 2. In the case where warmed-up air

flows into the space A through a gap space formed adjacent

to the wall surface li on the same side as the door 2, an

air baffle plate for suppressing such a flow of the warmed

up air may be disposed at an appropriate place.

[0017] Preferably, an air curtain is installed inside the

door 2 through which the workers come in and out of the room,

so that outdoor air does not enter the room when the workers

come in and out of the room.

[0018] In the embodiment, the plant cultivation apparatus

is a transplant cultivation apparatus. As illustrated in

Figs. 3 and 4, each of the multistage typed plant

cultivation shelves 3 to 8 is a box-shaped structure, which

is opened at its front surface and which includes a pedestal

10053881_1 (GHMaters) P108301.AU

3c, right and left side panels 3a, a rear panel 3b on the

rear side, and a top panel 3e defining a ceiling portion.

Inside the box-shaped structure, a plurality of plant

cultivation racks 12 is arranged in multiple stages at

certain intervals in the vertical direction.

[0019] Each of the multistage typed plant cultivation

shelves 3 to 8 has a height of about 2000 mm, i.e., such a

height as allowing the workers to carry out the operations

on all the stages. Preferably, a width of the plant

cultivation rack 12 is set to such a value, e.g., about 1000

mm to 2000 mm, that a plurality of resin-made plug trays,

each containing several tens to several hundreds cells

(small pots) arrayed in a grid pattern, can be placed side

by side, and that the temperature and the humidity in an

upper space above each rack 12 can be adjusted to be kept

constant. Furthermore, preferably, a depth of the plant

cultivation rack 12 is set to 500 mm to 1000 mm. A

plurality of cell trays 40 (see Fig. 1) are substantially

horizontally placed on each plant cultivation rack 12. In

general, dimensions of one plug tray are about 300 mm in

width and about 600 mm in length.

[0020] The plant cultivation rack 12 in the lowermost

stage is placed on the pedestal 3c. Levelness of the plant

cultivation rack 12 can be adjusted by an adjuster (not

illustrated) that is provided on the pedestal 3c.

10053881_1 (GHMaters) P108301.AU

[0021] An irrigation bed 30, described later, is provided

in each plant cultivation rack 12.

[0022] Artificial lighting units 13 are disposed at

respective lower surfaces of the plant cultivation racks 12

in the second or higher stages and of the top panel 3e such

that light from each artificial lighting device 13 is

applied to plants growing in the plug trays 40 on the plant

cultivation rack 12 positioned just under the relevant

artificial lighting device 13. In this embodiment, the

artificial lighting device 13 except for one in the

uppermost stage is mounted to a lower surface of an

irrigation tray 31 (described later).

[0023] A light source of the artificial lighting device 13

is preferably a fluorescent lamp or a LED, for example. In

this embodiment, a straight fluorescent lamp is used as a

light source.

[0024] Figs. 8 and 9 illustrate details of structure of

the artificial lighting device 13. Fig. 8 is a bottom view

of the artificial lighting device 13, and Fig. 9 is a

sectional view taken along a line IX-IX in Fig. 8. In the

artificial lighting device 13, plural pairs (six in this

embodiment) of sockets 13b are mounted to a lower surface of

a box 13a, and both ends of a fluorescent lamp 13c are

fitted to each pair of sockets 13b and 13b. A switch 13s is

further attached to the lower surface of the box 13a.

10053881_1 (GHMaters) P108301.AU

[0025] A box 13a is a box-like body having an upper plate

13d and a lower plate 13e. The lower plate 13e serves also

as a reflecting plate that reflects light from the

fluorescent lamp 13c. A power supply unit 13g incorporating

electric circuit components 13f, such as a stabilizer, an

inverter, a constant current circuit, a constant voltage

circuit, a current limiting resistance, etc., is disposed in

the box 13a. In this embodiment, three power supply units

13g are arranged between the fluorescent lamps 13c, i.e.,

between the fluorescent lamps 13c in first and second lines,

between the fluorescent lamps 13c in third and fourth lines,

and between the fluorescent lamps 13c in fifth and sixth

lines. The power supply units 13g are each mounted to the

lower plate 13e of the box 13a. A gap of about 3 to 30 mm

is left between each power supply unit 13g and the upper

plate 13d of the box 13a. In the artificial lighting device

13 of this embodiment, heat generated from the power supply

unit 13g is transmitted to the lower plate 13e and then

dissipated from the lower plate 13e. In other words, the

generated heat is transmitted to air flowing through a plant

cultivation space under the artificial lighting device 13.

Heat generated from each fluorescent lamp 13c is also

transmitted to that flow of air.

[0026] Because the gap is present between the power supply

unit 13g and the box upper plate 13d, an amount of heat

10053881_1 (GHMaters) P108301.AU transmitted from the power supply unit 13g to the upper plate 13d is very small. Therefore, the nutrient solution flowing on the irrigation tray 31 and the rhizosphere of the plants put in the plug tray 40 are prevented from being heated by the heat from the artificial lighting devices 13.

[0027] As illustrated in Fig. 4, ventilation openings are

formed in the rear panel 3b behind respective spaces (plant

cultivation spaces) between adjacent two of the plant

cultivation racks 12 and between the plant cultivation rack

12 in the uppermost stage and the top panel 3e, and air fans

are mounted respectively to the ventilation openings.

[0028] By arranging the air fans 15 at a back side of each

plant cultivation space, air flows uniformly in the plant

cultivation spaces, which is preferable.

[0029] An air-conditioning unit 9 with the function of

adjusting temperature and humidity of the air in the room

and circulating the air, which has been adjusted in

temperature and humidity to be matched with setting

conditions, is installed in an upper portion of the room.

The air-conditioning unit 9 includes an air-conditioning

unit body (air conditioner) 9A equipped with a heat

exchanger, and an air guide panel 10 mounted to a lower

surface of the air-conditioning unit body 9A. A compressor

for the air-conditioning unit body 9A is installed outside

the structure 1.

10053881_1 (GHMaters) P108301.AU

[0030] In this embodiment, the air-conditioning unit body

9A is positioned in a central region of the upper portion of

the room when viewing the room in plan. An inlet 9a of the

air-conditioning unit body 9A is provided in the lower

surface of the air-conditioning unit body 9A, and an

aperture 10a is formed in the air guide panel 10 at a

position overlapping the inlet 9a.

[0031] The air-conditioning unit body 9A is mounted to a

ceiling lt of the structure and has a structure that its

lateral surfaces are exposed to the interior of the room.

An air outlet 9b is provided in each of four lateral

surfaces of the air-conditioning unit body 9A.

[0032] A portion of the air guide panel 10 around the

aperture 10a is overlapped with a portion of the air

conditioning unit body 9A around the inlet 9a. The aperture

a has a size equal to or larger than that of the inlet 9a.

[0033] The air guide panel 10 is supported to the ceiling

lt with suspending attachments (not illustrated).

[0034] One end of the air guide panel 10 in the Y

direction is in contact with the wall surface lh. The other

end of the air guide panel 10 in the Y-direction extends up

to a position closer to the wall surface li than the

multistage typed plant cultivation shelves 3 to 5 and 6 to 8,

but it is slightly apart from the wall surface li. An

upright plate 1Cr is erectly provided along an overall side

10053881_1 (GHMaters) P108301.AU of the air guide panel 10 at the other end, and an upper end of the upright plate 10r is in contact with the ceiling lt.

[0035] The air guide panel 10 extends in the X-direction

up to a region between the ceiling lt and upper surfaces of

the multistage typed plant cultivation shelves 3 to 8.

[0036] As illustrated in Fig. 2a, both ends of the air

guide panel 10 in the X-direction are positioned vertically

above the front surfaces of the multistage typed plant

cultivation shelves 3 to 5 and the multistage typed plant

cultivation shelves 6 to 8 on the side closer to the space A,

or positioned rearward of those front surfaces, namely away

from those front surfaces toward the space B. A horizontal

distance L between each of both the ends of the air guide

panel 10 in the X-direction and corresponding one of the

front surfaces of the multistage typed plant cultivation

shelves 3 to 5 and 6 to 8 may be 0 mm, but it is preferably

not less than 30 mm, more preferably not less than 40 mm,

even more preferably not less than 90 mm, and still even

more preferably not less than 140 mm.

[0037] In this embodiment, spaces between both the ends of

the air guide panel 10 in the X-direction and the ceiling li

serve as blow-off openings 9f of the air-conditioning unit 9.

When viewing the plant cultivation shelves in plan, the

blow-off openings 9f may be overlapped with the front

surfaces of the multistage typed plant cultivation shelves 3

10053881_1 (GHMaters) P108301.AU to 8, but they are preferably positioned rearward of those front surfaces through the distance L.

[0038] In this embodiment, the inlet 9a of the air

conditioning unit body 9A serves as an intake opening of the

air-conditioning unit 9. When viewing the plant cultivation

shelves in plan, the intake opening is positioned forward of

the front surfaces of the multistage typed plant cultivation

shelves 3 to 8, namely on the side closer to the space A.

[0039] Air circulation flows denoted by arrows in Fig. 2a

are generated in the room by operating air fans 15. More

specifically, air having been adjusted in temperature and

humidity by the air-conditioning unit 9 is sucked into plant

cultivation spaces in stages of plant cultivation racks 12

from the space A on the open front side of the multistage

typed plant cultivation shelves 3 to 8, and is discharged to

the rear side of rear panels 3b through the air fans 15.

Then, the air rises through the space B between the rear

side of the rear panels 3b and the structure wall surfaces,

and passes through spaces C above the multistage typed plant

cultivation shelves 3 to 8 to be mixed with the air blown

out from the air-conditioning unit 9 and adjusted in

temperature and humidity. Then, the mixed air is blown out

toward the space A on the open front side of the multistage

typed plant cultivation shelves s 3 to 8 again after passing

between the air guide panel 10 and the multistage typed

10053881_1 (GHMaters) P108301.AU plant cultivation shelves 3 to 8.

[0040] Part of the air going to flow into the space A

after passing between the air guide panel 10 and the

multistage typed plant cultivation shelves 3 to 8 is sucked

into the inlet 9a of the air-conditioning unit body 9A

through the aperture 10a. After being adjusted in

temperature and humidity, the sucked air is blown out from

the blow-off openings 9f through the outlets 9b.

[0041] As illustrated in Figs. la, lb, 2a and 2b, when the

two rows of the multistage typed plant cultivation shelves 3

to 5 and the multistage typed plant cultivation shelves 6 to

8 are arrayed such that a working space is formed between

the two rows, the working space serves also as the space A

for air circulation, and effective circulation flows are

formed.

[0042] When the circulation flows pass through the plant

cultivation spaces in the multistage typed plant cultivation

shelves 3 to 8, water vapor evaporated from the irrigation

bed, culture media, the plants, etc. and the heat released

from the artificial lighting devices 13 are entrained with

the circulation flows. By circulating the circulation flows

at the temperature and the humidity adjusted by the air

conditioning unit 9 at all times, the inside of the room can

be kept as environment at the temperature and the humidity

optimum for growth of the plants. A flow speed of the air

10053881_1 (GHMaters) P108301.AU flowing through the plant cultivation spaces is preferably

0.1 m/sec or higher, more preferably 0.2 m/sec or higher,

and even more preferably 0.3 m/sec or higher. If the speed

of the air flow is too fast, there would be a risk that a

problem occurs in growth of the plants. Therefore, the flow

speed of the air is preferably 2.0 m/sec or lower.

[0043] While, in this embodiment, the air flow is streamed

from the front surface of the plant cultivation space to the

rear-side space B of the rack through the fans 15 in a state

under negative pressure, the air flow may be streamed

conversely from the rear surface side to the front surface

side of the rack in a state under positive pressure.

However, a more uniform air flow is obtained in the plant

cultivation space by causing the air flow to stream from the

front surface side to the rear surface side of the rack in a

state under negative pressure.

[0044] In this embodiment, a rack plate of each plant

cultivation rack 12 is constituted by the irrigation tray 31

of the irrigation bed (subirrigation bed) 30, and irrigation

is effectuated from a bottom surface of the plug tray 40

that is placed on the irrigation tray 31. An example of a

structure of the irrigation bed 30 will be described below

with reference to Figs. 5 to 7. Fig. 5 is a plan view of

the irrigation bed, Fig. 6 is a perspective view thereof,

and Fig. 7 is a sectional view taken along a line VII-VII in

10053881_1 (GHMaters) P108301.AU

Fig. 5.

[0045] The irrigation bed 30 includes the rectangular

irrigation tray 31 having sidewalls 31a, 31b and 31c that

are erected respectively at a rear side and left and right

lateral sides of a lower plate 31d. A drain pit 32 in

continuity with the lower plate 31d of the irrigation tray

31 is formed along a front side of the irrigation tray 31

where there is no sidewall, and aide drain opening 32a is

formed at one end of the drain pit 32. The drain pit 32 and

the lower plate 31d are partitioned by a dam 34, and the

nutrient solution flows out into the drain pit 32 from

cutouts 34a that are formed at both ends of the dam 34.

Furthermore, a feed pipe 33 for supplying the nutrient

solution into the irrigation tray 31 is disposed to extend

along the sidewall 31a erected at the rear side of the

irrigation tray 31. The nutrient solution is supplied onto

the tray 31 through a plurality of small holes 33a formed in

the feed pipe 33.

[0046] A plurality of ribs 35, each having a height of

about 7 mm, is disposed on an upper surface of the lower

plate 31d of the irrigation tray to extend toward the drain

pit 32 parallel to each other. The plug tray 40 is placed

on the ribs 35.

[0047] The irrigation bed 30 is dimensioned, as

illustrated in Fig. 4, such that when the irrigation trays

10053881_1 (GHMaters) P108301.AU

31 are placed on the plant cultivation racks 12 of the

multistage typed plant cultivation shelves 3 to 6, the drain

pits 32 are positioned to project from the open front

surfaces of the plant cultivation shelves 3 to 8. With the

drain pits 32 projecting from the open front surfaces of the

plant cultivation shelves, it is easier to collect the

nutrient solution drained through the drain openings 32a of

the drain pits 32 of the irrigation trays 31 placed in the

plant cultivation rack 12 of each stage, and to drain the

nutrient solution to the outside of the structure 1.

[0048] When the nutrient solution is continuously supplied

through the small holes 33a formed in the feed pipe 33 of

the irrigation bed 30, the nutrient solution is stemmed by

the dam 34 and is pooled up to a predetermined level. While

the nutrient solution is supplied from the feed pipe 33, the

nutrient solution flows out to the drain pit 32 through the

cutouts 34a a little by a little. A pooled state of the

nutrient solution is preferably maintained in the irrigation

tray 31 at a level of, e.g., about 10 to 12 mm by adjusting

supply rate of the nutrient solution and drain rate of the

nutrient solution of the cutouts 34a. The water is sucked

up by the capillary action to the culture medium in each

cell 41 through cell holes 42, which are formed in the

bottom surface of each cell 41 in the cell tray 40 placed on

the ribs 35, such that the culture media in all the cells 41

10053881_1 (GHMaters) P108301.AU are brought into a water saturated state in a short time.

[0049] The artificial lighting device 13 is mounted to a

lower surface of the lower plate 31d of the irrigation tray

31. While, in this embodiment, the upper plate 13d of the

box 13a of the artificial lighting device 13 is directly

contacted with the lower surface of the irrigation tray 31,

a spacer or a heat insulating material may be interposed

therebetween.

[0050] In the irrigation bed 30 of this embodiment, as

illustrated in Fig. 7, an upper surface of the lower plate

31d of the irrigation tray 31 is inclined toward the drain

pit 32. Therefore, when the irrigation is stopped, the

nutrient solution can be drained to the drain pit 32 in a

short time. In the case of inclining the upper surface of

the lower plate 31d, the cell tray 40 placed on the ribs 35

can be horizontally held by gradually changing the height of

each rib 35 such that a top 35a of the rib lies horizontally.

[0051] Fig. 10 illustrates another example of the

irrigation bed used in the present invention. The same

members as those in Figs. 5 to 7 are denoted by the same

reference signs. In an irrigation bed 30' illustrated in

Fig. 10, when the cell tray 40 is placed on the lower plate

31d of the irrigation tray 31, an under tray 50 is

interposed between the lower plate 31d of the irrigation

tray 31 and the plug tray 40. The under tray 50 has

10053881_1 (GHMaters) P108301.AU rigidity at such a level as being able to support the plug tray 40 including the cells 41 in each of which the culture medium is put. A plurality of small holes 51 is formed in a bottom surface of the under tray 50, and a plurality of projections 52 is formed on the rear side of the under tray

50. The projections 52 function as gap holding means for

holding a gap between the lower plate 31d of the irrigation

tray 31 and the bottom surface of the cell tray 40 when the

cell tray 40 is accommodated in the irrigation tray 31

together with the under tray 50.

[0052] Also in the irrigation bed 30' of Fig. 10, when the

nutrient solution is supplied from the feed pipe 33 of the

irrigation bed 30' and is pooled up to a predetermined level,

the nutrient solution is introduced into the under tray 50

through the small holes 51 of the under tray 50. The water

is then sucked up by the capillary action to the culture

medium in each cell 41 through the cell holes 42, which are

formed in the bottom surface of each cell 41 in the plug

tray 40.

[0053] Furthermore, in Fig. 10, the artificial lighting

device 13 is similarly mounted to the lower surface of the

lower plate 31d of the irrigation tray 31.

[0054] As in the above-described embodiment, the plug tray

placed on the irrigation tray 31 is constituted as a

unitary tray shape including several tens to several

10053881_1 (GHMaters) P108301.AU hundreds cells 41 arrayed in a grid pattern, and dimensions of one plug tray are about 300 mm in width and about 600 mm in length. However, the present invention is not limited to the above-described arrangement.

[0055] To artificially supply carbon dioxide consumed by

transplants for photosynthesis, as illustrated in Figs. la

and 1b, a liquefied carbon dioxide cylinder 16 is installed

outside the structure 1. The carbon dioxide is supplied

from the liquefied carbon dioxide cylinder 16 such that a

concentration of the carbon dioxide in the room, measured

using a carbon dioxide concentration meter, is held constant.

[0056] By employing the above-described plant cultivation

apparatus to grow transplants, it is possible to

automatically adjust environment conditions, such as a

quantity of light, temperature, humidity, carbon dioxide,

and water, which are suitable for the growth of the

transplants. Since all the transplants on the plant

cultivation racks can be grown under the same environment,

uniformity in quality of the grown transplants can be

increased.

[0057] In this embodiment, since the blow-off openings 9f

of the air-conditioning unit 9 are positioned rearward of

the front surfaces of the multistage typed plant cultivation

shelves 3 to 8 through 30 mm or more, the air warmed up

while passing through the multistage typed plant cultivation

10053881_1 (GHMaters) P108301.AU shelves 3 to 8 (cultivation modules) and the air cooled down by the air-conditioning unit 9 flow into the space A in a state mixed together. As a result, the air flowing into the space A becomes air having a uniform temperature, and is then taken into the multistage typed plant cultivation shelves 3 to 8.

[0058] If the air cooled by the air-conditioning unit 9

directly flows into the space A, air being partly cold would

be taken into the multistage typed plant cultivation shelves

3 to 8 through the front surfaces. Therefore, a temperature

variation would occur among the multistage typed plant

cultivation shelves 3 to 8, and growth of plants would be

not uniform.

[0059] In this embodiment, since the air-conditioning unit

body 9A and the air guide panel 10 are integrated with each

other, an advantageous structure is obtained in that there

is no need of installing many lines of duct piping, etc.

[0060] In the above-described the multistage typed plant

cultivation shelves, the heat generated from the artificial

lighting device 13 is transmitted to the box lower plate 13e,

which serves also as the reflecting plate, and is further

transmitted from the lower plate 13e to the air flowing

through the plant cultivation space. An amount of the heat

transmitted from the artificial lighting device 13 to the

irrigation tray 31 on the upper side is very small.

10053881_1 (GHMaters) P108301.AU

Accordingly, the temperature of the nutrient solution

residing on the irrigation tray 31 can be controlled to be

kept within a predetermined range.

[0061] Another embodiment of the plant cultivation

apparatus according to the present invention will be

described below.

[0062] The plant cultivation apparatus of this embodiment

includes at least one air-conditioning unit that adjusts

environments in a closed space, and a cultivation module

that is opened at a front surface. In the cultivation

module, plant cultivation racks are arranged in multiple

stages in an up-down direction to form plant cultivation

spaces. An intake opening and a blow-off opening of the

air-conditioning unit are positioned forward of the front

surface of the cultivation module when viewing the plant

cultivation apparatus in plan. An air guide panel is

positioned between the outlet of the air-conditioning unit

body and the front surface of the growth module.

[0063] Figs. 11a and lb illustrate one example of the

above plant cultivation apparatus. Fig. 11a illustrates a

cross-section similar to that illustrated in Fig. 2a, and

Fig. 11b illustrates a cross-section taken along a line XIb

XIb in Fig. 11a.

[0064] In this embodiment, an air-conditioning unit 9'

includes an air-conditioning unit body 9A' and an air guide

10053881_1 (GHMaters) P108301.AU panel 10'. The air-conditioning unit body 9A' is installed in a state fitted to an opening is for installation of the air-conditioning unit, the opening is being formed in the ceiling lt of the structure 1. A lower surface of the air conditioning unit body 9A' is slightly projected downward from a lower surface of the ceiling lt.

[0065] Air outlets 9b' are formed in a peripheral edge

portion of the lower surface of the air-conditioning unit

body 9A', while an air inlet 9a' is formed in a central

region of the lower surface of the air-conditioning unit

body 9A' on the inner side of the peripheral edge portion.

[0066] Cooled air is blown out from the outlet 9b' in

directions (four directions) away from the air-conditioning

unit body 9A'.

[0067] The air guide panel 10' is arranged at an

intermediate level between the ceiling lt and an upper

surface level of the multistage typed plant cultivation

shelves 3 to 8, and is suspended from the ceiling lt with

suspension attachments. An aperture i0a' allowing air to

pass therethrough upward from below is formed in the air

guide panel 10' at a position under the inlet 9a' of the

air-conditioning unit body 9A'.

When the cooled air discharged from the outlets 9b'

tend to directly flow into the inlet 9a', an air baffle

plate for suppressing such a flow of the cooled-up air may

10053881_1 (GHMaters) P108301.AU be disposed at an appropriate place.

[0068] As illustrated in Fig. 11a, both ends of the air

guide panel 10' in the X-direction are positioned vertically

above the front surfaces of the multistage typed plant

cultivation shelves 3 to 5 and the multistage typed plant

cultivation shelves 6 to 8 on the side closer to the space A,

or positioned rearward of those front surfaces, namely away

from those front surfaces toward the space B. A preferable

range of a horizontal distance L between each of both the

ends of the air guide panel 10' in the X-direction and

corresponding one of the front surfaces of the multistage

typed plant cultivation shelves 3 to 5 and 6 to 8 is similar

to that in the above-described embodiment.

[0069] A preferable range of a horizontal distance between

each of both the ends of the air guide panel 10' in the X

direction and corresponding one of the rear surfaces of the

multistage typed plant cultivation shelves 3 to 5 and 6 to 8

is also similar to that in the above-described embodiment.

[0070] An upright plate 1Cr' is provided in the air guide

panel 10' as in the air guide panel 10. Other structures of

the plant cultivation apparatus illustrated in Figs. 11a and

11b are similar to those of the plant cultivation apparatus

illustrated in Figs. la to 10, and the same reference signs

denote the same components.

[0071] In this embodiment, spaces between both the ends of

10053881_1 (GHMaters) P108301.AU the air guide panel 10' in the X-direction and the ceiling li and the ceiling lt serve as blow-off openings 9f' of the air-conditioning unit 9'. When viewing the plant cultivation apparatus in plan, the blow-off openings 9f' may be overlapped with the front surfaces of the multistage typed plant cultivation shelves 3 to 8, but they are preferably positioned rearward of those front surfaces through the distance L.

[0072] In this embodiment, the aperture 10a' in the air

guide panel 10' serves as an intake opening of the air

conditioning unit. When viewing the plant cultivation

apparatus in plan, the intake opening is positioned forward

of the front surfaces of the multistage typed plant

cultivation shelves 3 to 8, namely on the side closer to the

space A.

[0073] Also in the plant cultivation apparatus constituted

as described above, air warmed up while passing through the

multistage typed plant cultivation shelves 3 to 8 (growth

modules) and air cooled down by the air-conditioning unit

can be caused to flow into the front side of the growth

modules in a state mixed together. As a result, the air

flowing into the front side of the growth modules becomes

air having a uniform temperature, and is then taken into the

growing modules.

[0074] In the present invention, a ratio Wb/Wa of a total

10053881_1 (GHMaters) P108301.AU cooling capacity (Wb) of all the air-conditioning units to a total power consumption (Wa) of all the illumination devices

(i.e., the fluorescent lamps 13c in the above-described

embodiment) is preferably not less than 1 and not more than

, more preferably not less than 1 and not more than 4, even

more preferably not less than 1 and not more than 3, and

most preferably not less than 1 and not more than 2. By

setting Wb/Wa to fall in the above-mentioned range, the

environments in the closed space can be kept appropriate and

constant, and environmental changes caused by turning-on/off

of the air-conditioning units can be held smaller. Wb/Wa

cab be expressed by the following formula A on an assumption

that a power consumption of one illumination device such as

the fluorescent lamp is denoted by Ws, the number of the

illumination devices is denoted by n, and a cooling capacity

of one air-conditioning unit is denoted by Wk, and the

number of the installed air-conditioning units is denoted by

m.

[0075] A= Wb/Wa

= (Wk x m)/(Ws x n)

m: number of air-conditioning units

n: number of illumination devices

[0076] The above-described embodiment is one example of

the present invention, and the present invention is not

limited to the above-described embodiment. For instance,

10053881_1 (GHMaters) P108301.AU the size of the room and the number of the multistage typed plant cultivation shelves to be installed may be other than those described above. The air-conditioning unit body may be installed at a position other than the central region.

The air-conditioning unit body may be installed two or more,

but the number of the air-conditioning unit bodies is

preferably as small as possible.

EXAMPLES

[0077] <EXAMPLE 1>

Two growth modules (multistage typed plant cultivation

shelves), each having five stages and three racks, were

installed in an opposing relation in a completely-closed

space within a closed structure. As illumination devices,

six fluorescent lamps (output power of 45 W per lamp) were

installed in each of the racks, namely 180 lamps in total.

One air-conditioning unit with the cooling capacity of 14 kW

was installed. An A-value (value of Wb/Wa) was 1.7.

[0078] Spinach was cultivated by installing the air

conditioning unit body 9A in a central region of the ceiling

between the growth modules, disposing the air guide panel 10

as per illustrated, and by arranging the blow-off openings

9f of the air-conditioning unit 9 at positions rearward of

front surfaces of the growth modules through 50 mm.

Thermometers were set in the racks of the growth modules in

a one-to-one relation, and a difference (hereinafter called

10053881_1 (GHMaters) P108301.AU a "maximum temperature difference") AT between maximum one and minimum one of temperatures measured in all the racks at the same time was calculated.

[0079] The maximum temperature difference AT among all the

racks was 1°C.

[0080] <EXAMPLE 2>

Spinach was cultivated under the same conditions as

those in EXAMPLE 1 except for arranging the blow-off

openings 9f of the air-conditioning unit 9 at positions

rearward of the front surfaces of the growth modules through

150 mm.

The maximum temperature difference AT among all the

racks was 1.5°C.

[0081] <EXAMPLE 3>

Spinach was cultivated under the same conditions as

those in EXAMPLE 1 except for arranging the blow-off

openings 9f of the air-conditioning unit 9 at positions

rearward of the front surfaces of the growth modules through

450 mm.

The maximum temperature difference AT among all the

racks was 1.8°C.

[0082] <COMPARATIVE EXAMPLE 1>

Spinach was cultivated under the same conditions as

those in EXAMPLE 1 except for arranging the blow-off

openings 9f of the air-conditioning unit 9 at positions

10053881_1 (GHMaters) P108301.AU forward of the front surfaces of the growing modules through

600 mm.

The maximum temperature difference AT among all the

racks was 4°C.

[0083] <COMPARATIVE EXAMPLE 2>

Spinach was cultivated under the same conditions as

those in EXAMPLE 1 except for arranging the blow-off

openings 9f of the air-conditioning unit 9 at positions

forward of the front surfaces of the growth modules through

100 mm.

The maximum temperature difference AT among all the

racks was 4°C.

[0084] While the present invention has been described in

detail above in connection with the particular embodiments,

it is apparent to those skilled in the art that the present

invention can be variously modified without departing from

the gist and the scope of the present invention.

This application claims the benefit of Japanese Patent

Application No. 2015-184190 filed on September 17, 2015,

which is hereby incorporated by reference herein in its

entirety.

[0085]

1 closed structure

3-8 multistage typed plant cultivation shelves

3a side panel

10053881_1 (GHMaters) P108301.AU

3b backside panel

3c pedestal

3e top panel

9, 9' air-conditioning unit

9A, 9A' air-conditioning unit main body

9a, 9a' inlet (intake opening)

9b, 9b' outlet

9f, 9f' blow-off opening

10, 10' air guide panel

10a, 10a' aperture

12 plant cultivation rack

13 artificial lighting device

13a box

13b socket

13c fluorescent lamp

13d upper plate

13e lower plate

13f electric circuit components

13g power supply unit

13s switch

15 air fan

16 liquefied carbon dioxide cylinder

30, 30' irrigation bed

31 irrigation tray

31d lower plate

10053881_1 (GHMaters) P108301.AU

32 drain pit

32a drain opening

33 feed pipe

33a small hole

34 dam

34a cutout

35 rib

40 plug tray

41 cell

42 cell hole

50 under tray

51 small hole

52 projection

[0078] It is to be understood that, if any prior art

publication is referred to herein, such reference does not

constitute an admission that the publication forms a part of

the common general knowledge in the art, in Australia or any

other country.

[0079] In the claims which follow and in the preceding

description of the invention, except where the context

requires otherwise due to express language or necessary

implication, the word "comprise" or variations such as

"comprises" or "comprising" is used in an inclusive sense,

i.e. to specify the presence of the stated features but not

16758879_1 (GHMatters) P108301.AU to preclude the presence or addition of further features in various embodiments of the invention.

16758879_1 (GHMatters) P108301.AU

Claims

[Claim 1]

A plant cultivation apparatus comprising:

a structure that defines a closed space;

at least one air-conditioning unit installed in the

structure at a ceiling; and

a growth module arranged in the structure and opened at

a front surface,

the growth module including plant cultivation racks

arranged in multiple stages in an up-down direction to form

plant cultivation spaces,

wherein, when viewing the plant growth apparatus in

plan, an intake opening of the air-conditioning unit is

positioned forward of the front surface of the growth module,

and a blow-off opening of the air-conditioning unit is

positioned in alignment with the front surface or rearward

of the front surface,

wherein the growth module is disposed in plural numbers

inside the structure with the front surfaces of the growth

modules positioned in an opposing relation and with a space

A formed between the opposing front surfaces,

the air-conditioning unit body is arranged above the

space A,

a space B is formed between a rear surface of each of

the growth modules and a wall surface of the structure, and

16758879_1 (GHMatters) P108301.AU air flows from the space A to the space B after passing through each of the growth modules.
[Claim 2]

The plant cultivation apparatus according to Claim 1,

wherein the blow-off opening is positioned rearward of the

front surface of the growth module through 30 mm or more.
[Claim 3]

The plant cultivation apparatus according to Claim 1 or

2, wherein the air-conditioning unit includes:

an air-conditioning unit body mounted to the ceiling,

and including an air inlet, an air outlet, and a temperature

adjusting section configured to adjust air temperature; and

an air guide panel arranged above the growth module and

guiding air blown out from the outlet of the air

conditioning unit body to a region above the growth module,

and

wherein a space between an end of the air guide panel

on side overlapping the growth module and the ceiling serves

as the blow-off opening of the air-conditioning unit.
[Claim 4]

The plant cultivation apparatus according to Claim 3,

wherein the air-conditioning unit body includes the inlet

formed in a lower surface thereof, and the outlet formed in

a lateral surface thereof,

the air guide panel includes an aperture overlapping

16758879_1 (GHMatters) P108301.AU the inlet and is attached, at a peripheral edge portion around the aperture in the air guide panel, to a peripheral edge portion of the lower surface of the air-conditioning unit body, and the inlet serves as the intake opening.
[Claim 5]

The plant cultivation apparatus according to Claim 3,

wherein the air-conditioning unit body includes the inlet

formed in a central region of a lower surface thereof, and

the outlet formed in a peripheral region of the lower

surface,

the air guide panel is positioned away from the lower

surface of the air-conditioning unit body downward,

the air guide panel includes an aperture formed at a

position under the inlet of the air-conditioning unit body,

and

the aperture serves as the inlet opening.
[Claim 6]

The plant cultivation apparatus according to Claim 5,

wherein at least one air fan is disposed on rear side of the

growth modules.
[Claim 7]

The plant cultivation apparatus according to any one of

Claims 1 to 6, wherein the growth module includes at least

one artificial lighting device, and

16758879_1 (GHMatters) P108301.AU a ratio Wb/Wa of a total cooling capacity (Wb) of all the air-conditioning units to a total power consumption (Wa) of all the artificial lighting devices is not less than 1 and not more than 5.
[Claim 8]

A plant cultivation method of growing plants by

employing the plant cultivation apparatus according to any

one of Claims 1 to 7.

16758879_1 (GHMatters) P108301.AU