Patent Publication Number: US-2023148499-A1

Title: Cultivation equipment

Description:
TECHNICAL FIELD 
     The present disclosure relates to cultivation equipment. 
     BACKGROUND ART 
     Patent Literature 1 describes a multistage plant cultivation apparatus including a cultivation bed installed in each stage, a nourishing liquid necessary for the growth of plants circulating in the cultivation bed. 
     Incidentally, in the multistage plant cultivation apparatus described in Patent Literature 1, it is necessary to increase the number of stages in order to increase the harvest amount per unit area. 
     However, when the number of stages is increased, the number of pipes for supplying and discharging the nourishing liquid to and from the cultivation bed is increased, and thus there is a possibility that equipment for plant cultivation becomes complicated. Moreover, in order to supply the nourishing liquid to a cultivation bed on a high stage, a thick pipe or a large-capacity pump is required. This may lead to upsizing of the equipment for plant cultivation. 
     CITATION LIST 
     Patent Literature 
     
         
         Patent Literature 1: JP H03-232434 A 
       
    
     SUMMARY OF THE INVENTION 
     An object of the present disclosure is to propose cultivation equipment that can curb complication and upsizing of the equipment even when the number of cultivation stages is increased. 
     Cultivation equipment according to one aspect of the present disclosure includes: a storage shelf; a plurality of cultivation tanks that are stored in the storage shelf and hold plants and a cultivation liquid; a discharge device that is movable among the plurality of cultivation tanks and discharges the cultivation liquid from each of the plurality of cultivation tanks; and a supply device that is movable among the plurality of cultivation tanks and supplies the cultivation liquid to each of the plurality of cultivation tanks. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a front view schematically illustrating a main part of cultivation equipment of Embodiment 1 according to the present disclosure. 
         FIG.  2    is a plan view schematically illustrating a cultivation building in which the cultivation equipment is installed. 
         FIG.  3    is a front view schematically illustrating the cultivation equipment. 
         FIG.  4    is a side view schematically illustrating the cultivation equipment. 
         FIG.  5    is a perspective view schematically illustrating a conveyance device included in the cultivation equipment. 
         FIG.  6    is a front view schematically illustrating a treatment apparatus included in the cultivation equipment. 
         FIG.  7    is a perspective view illustrating Modification  1  of the cultivation unit included in the cultivation equipment. 
         FIG.  8 A  is a plan view illustrating Modification  2  of a cultivation unit included in the cultivation equipment, and  FIG.  8 B  is a side view illustrating Modification  2  of the cultivation unit. 
         FIG.  9    is a front view illustrating Modification  3  of the cultivation unit included in the cultivation equipment. 
         FIG.  10    is a side view schematically illustrating cultivation equipment of Embodiment 2 according to the present disclosure. 
         FIG.  11    is a front view schematically illustrating the cultivation equipment. 
         FIG.  12    is a side view illustrating a discharge device and a conveyance device included in the cultivation equipment. 
         FIG.  13    is another side view schematically illustrating the cultivation equipment. 
         FIG.  14    is another front view schematically illustrating the cultivation equipment. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     1. Embodiment 1 
     1.1 Overview 
       FIG.  1    schematically illustrates a main part of cultivation equipment of Embodiment 1. The cultivation equipment includes storage shelf  1 , a plurality of cultivation units  2  stored in the storage shelf  1 , and a plurality of cultivation tanks  3  installed in the plurality of cultivation units  2  and holding plants P 1  and a cultivation liquid L 1 . The cultivation equipment further includes a discharge device  50  and a supply device  51 . The discharge device  50  is movable among the plurality of cultivation tanks  3 , and discharges the cultivation liquid L 1  from each of the plurality of cultivation tanks  3 . The supply device  51  is movable among the plurality of cultivation tanks  3 , and supplies the cultivation liquid L 1  to each of the plurality of cultivation tanks  3 . 
     In the cultivation equipment having the above configuration, the discharge device  50  and the supply device  51  which are movable among the plurality of cultivation tanks  3  can discharge and supply the cultivation liquid L 1  to and from each of the plurality of cultivation tanks  3  of the plurality of cultivation units  2  stored in the storage shelf  1 . For this reason, in this cultivation equipment, there is no need to install a large number of pipes for supplying and discharging the cultivation liquid L 1  on the storage shelf  1 . Hence, it is possible to prevent complication and upsizing of the equipment, so that the storage shelf  1  is easily increased in height, and the harvest amount per unit area is easily increased. 
     Additionally, in this cultivation equipment, when the cultivation unit  2  is conveyed between a work station A 1  for performing various works and the storage shelf  1 , the plurality of cultivation tanks  3  of the cultivation unit  2  can be kept in a state where the cultivation tanks  3  do not contain or substantially do not contain the cultivation liquid L 1 . Accordingly, with this cultivation equipment, the weight of the cultivation unit  2  at the time of conveyance can be reduced, the load of conveyance can be reduced, and also liquid leakage from each cultivation tank  3  at the time of conveyance can be prevented. 
     1.2 Details 
     Next, the cultivation equipment of the present embodiment will be described in more detail. The cultivation equipment is equipment for hydroponically cultivating the plant P 1  to be cultivated. The cultivation equipment of the present embodiment further includes a conveyance device  4  that conveys at least one of the plurality of cultivation units  2  between the storage shelf  1  and the work station A 1  separated from storage shelf  1 . The discharge device  50  and the supply device  51  are conveyed by the conveyance device  4 . As illustrated in  FIG.  2   , the cultivation equipment is installed in a cultivation building  100 . In the present embodiment, the cultivation equipment includes the storage shelf  1  long in one horizontal direction. Hereinafter, each configuration will be described with the longitudinal direction of the storage shelf  1  in the horizontal direction as direction D1, the short direction of the storage shelf  1  in the horizontal direction as direction D2, and the height direction of the storage shelf  1 , that is, the vertical direction thereof as direction D3. 
     1.2.1 Cultivation Building 
     As illustrated in  FIG.  2   , the cultivation building  100  includes a cultivation room  101  and a work room  102 . The work room  102  is a room different from the cultivation room  101  separated by a wall  103 . 
     In the present embodiment, the cultivation building  100  includes a plurality of work rooms  102  arranged in direction D3, that is, in the vertical direction. The cultivation room  101  is one room having a height similar to the total height of the plurality of work rooms  102 . 
     The cultivation room  101  is a room for cultivating the plant P 1 , and the storage shelf  1  is installed in cultivation room. The environment of the cultivation room  101  is set to a temperature and humidity suitable for cultivation of the plant P 1 , for example. 
     The work room  102  is a room for performing various works such as planting, harvesting, cleaning, and inspecting on the plurality of cultivation tanks  3  of the cultivation unit  2  conveyed to the work room  102 . A space in the work room  102  is the work station A 1 . In the plurality of work rooms  102 , a different work is performed in each room, for example. 
     The wall  103  is provided with an entrance  104  that connects the cultivation room  101  and the work room  102  on each floor. In the present embodiment, the cultivation room  101  and the work room  102  on each floor are connected to each other through one entrance  104 . That is, the wall  103  is provided with the same number of entrances  104  as the number of the plurality of work rooms  102 . 
     The cultivation building  100  includes a plurality of automatic doors  105  that open and close the plurality of entrances  104  in the wall  103 . Each automatic door  105  opens the entrance  104  only when the cultivation unit  2  moves between the cultivation room  101  and the work room  102 , and closes the entrance  104  at other times. As a result, in the cultivation building  100 , the environment in the cultivation room  101  can be easily maintained under conditions suitable for cultivation of the plant P 1 . That is, the temperature and humidity in the cultivation room  101  can be easily kept constant, and the air in each work room  102  can be prevented from flowing into the cultivation room  101 . 
     The conveyance device  4  moves the cultivation unit  2  between the cultivation room  101  and the work room  102 . 
     1.2.2 Storage Shelf 
     As illustrated in  FIGS.  2  and  3   , the cultivation equipment includes a plurality of storage shelves  1 . The plurality of storage shelves  1  are arranged at intervals in direction D2 and are parallel to each other. The plurality of storage shelves  1  include a plurality of sets of a pair of storage shelves  1  positioned across a conveyance passage of the cultivation unit  2  from each other. A set of the pair of storage shelves  1  and another set of the pair of storage shelves  1  arranged in direction D2 are positioned adjacent to each other, that is, with a narrower interval than the conveyance passage. The number of storage shelves  1  included in the cultivation equipment is appropriately set according to the area of the cultivation room  101  and the like. 
     As illustrated in  FIGS.  3  and  4   , the storage shelf  1  is a multistage shelf having a plurality of shelf members  10  arranged at intervals in direction D3, that is, the vertical direction. The storage shelf  1  further includes a plurality of columns  11  that support the plurality of shelf members  10 . The plurality of shelf members  10  and the plurality of columns  11  are both made of metal, for example. The plurality of columns  11  include a plurality of sets of two columns  11  arranged at an interval in direction D2 at intervals in direction D1. 
     The size of the storage shelf  1  is, for example, 20 m in length in direction D1, 2.1 m in length in direction D2, and 10 m in length in direction D3. The size of the storage shelf  1  can be appropriately set according to the size of cultivation room  101  and the number of cultivation units  2  to be loaded. 
     The storage shelf  1  further includes a power transmitter  12  that supplies power to an irradiation device  22  included in the cultivation unit  2 . The power transmitter  12  is electrically connected to a power supply such as a commercial power supply to obtain power. In the present embodiment, the power transmitter  12  supplies power to the irradiation device  22  by wireless power transfer. 
     As illustrated in  FIG.  4   , the storage shelf  1  includes a plurality of storage areas A 2  arranged in each of direction D1 and direction D3. One cultivation unit  2  is stored in each of the plurality of storage areas A 2 . 
     The storage areas A 2  adjacent in direction D3, that is, the vertical direction, are separated by the shelf members  10 . Two storage areas A 2  adjacent to each other in direction D1 are separated by two columns  11  arranged in direction D2. 
     1.2.3 Cultivation Unit 
     Each of the plurality of cultivation units  2  is a multistage shelf on which the plurality of cultivation tanks  3  can be placed. The plurality of cultivation units  2  have the same structure. The cultivation unit  2  can be taken in and out of the storage shelf  1 . 
     As illustrated in  FIG.  1   , the cultivation unit  2  includes a plurality of support plates  20  arranged at intervals in direction D3, and a plurality of columns  21  that support the plurality of support plates  20 . The plurality of support plates  20  and the plurality of columns  21  are both made of metal, for example. 
     The size of the cultivation unit  2  is, for example, 1.8 m in length in direction D2, 1.5 m in length in direction D1, and 2.0 m in length in direction D3, that is, in the vertical direction. In this case, various works can be easily performed on each of the cultivation tanks  3  on the cultivation unit  2  in a state where the cultivation unit  2  is disposed in the work station A 1 . 
     In the present embodiment, the cultivation unit  2  includes five support plates  20  and four columns  21 . Each of the five support plates  20  has a rectangular shape in plan view, and its four corners are supported by four columns  21 . The number of support plates  20  included in the cultivation unit  2  can be set as appropriate. In the present embodiment, each of the plurality of support plates  20  has a flat rectangular box shape opened downward. 
     The cultivation unit  2  further includes a plurality of irradiation devices  22  that irradiate each of the plurality of cultivation tanks  3  with grow light. In the present embodiment, each of the plurality of irradiation devices  22  is attached to a lower surface of a corresponding one of the plurality of support plates  20  except for the lowermost support plate  20 . Each of the plurality of irradiation devices  22  is a light emitting diode (LED) lamp  220 . The LED lamp  220  is accommodated within the thickness of the box-shaped support plate  20 . 
     The cultivation unit  2  further includes a power receiver  23  to which power is supplied from the power transmitter  12  of the storage shelf  1  by wireless power transfer. The power receiver  23  is provided on the lowermost support plate  20 . The LED lamp  220  is electrically connected to the power receiver  23  through electric wiring (not illustrated). 
     In the cultivation unit  2 , the cultivation tank  3  is disposed on each of the plurality of support plates  20  except for the uppermost support plate  20 . As illustrated in  FIG.  4   , in the present embodiment, two cultivation tanks  3  are disposed so as to be adjacent to each other in direction D1 on each support plate  20 . For this reason, a total of eight cultivation tanks  3  are installed in one cultivation unit  2 . Each support plate  20  is provided with positioning means (not illustrated) that fixes the position of each of the two cultivation tanks  3 . 
     1.2.4 Cultivation Tank 
     As illustrated in  FIG.  1   , each of the plurality of cultivation tanks  3  is a cultivation container that holds plants P 1  and the cultivation liquid L 1  for growing the plants P 1 . The plurality of cultivation tanks  3  have the same structure. 
     The cultivation tank  3  includes a flat box-shaped tray  30  opened upward, and a planting panel  31  attached to an upper part of the tray  30 . The cultivation liquid L 1  is held in the tray  30 . Each of the tray  30  and the planting panel  31  has a substantially rectangular shape in plan view. Each of the tray  30  and the planting panel  31  is a resin molded article, and is formed by vacuum molding, for example. 
     The size of the cultivation tank  3  is, for example, 1300 mm in length in direction D2, 700 mm in length in direction D1, and 70 mm in length in direction D3. The cultivation tank  3  is provided in a portable size. In the present embodiment, 15 liters of the cultivation liquid L 1  can be stored in the tray  30 . 
     The planting panel  31  is provided with a plurality of openings  310  for holding the plants P 1 . The plurality of openings  310  are arranged at intervals on the entire planting panel  31 . The number and intervals of the plurality of openings  310  provided in the planting panel  31  are appropriately set according to the growth stage and the type of the plant P 1  to be held. 
     The planting panel  31  and the tray  30  are provided with a locking structure that locks the parts onto each other. This makes it possible to curb displacement of the planting panel  31  with respect to the tray  30  during conveyance of the cultivation unit  2 . 
     Each of a plurality of types of planting panels  31  can be attached to the tray  30 . The plurality of types of planting panels  31  include, for example, a first planting panel  31  used from the initial stage of cultivation to the middle stage of cultivation, and a second planting panel  31  used from the middle stage of cultivation to the harvest period. The first planting panel  31  has a larger number of openings  310  than the second planting panel  31 , and the interval between adjacent openings  310  is narrower. By attaching the planting panel  31  corresponding to the growth stage of the plant P 1  to the tray  30 , the plant P 1  can be cultivated efficiently in the cultivation tank  3 . 
     The planting panel  31  is provided with a through hole  311  used for discharging the cultivation liquid L 1  in the tray  30  and supplying the cultivation liquid L 1  into the tray  30 . The through hole  311  penetrates the planting panel  31  in direction D3, that is, in the vertical direction. The through hole  311  is provided at an end on one side in direction D2 of the planting panel  31 , specifically, at an end on the side of the conveyance passage between the pair of storage shelves  1 . The through hole  311  is formed at a fixed position regardless of the type of the planting panel  31 . 
     1.2.5 Conveyance Device 
     The conveyance device  4  is a device that conveys each of the plurality of cultivation units  2  one by one between the storage shelf  1  and the work station A 1 . The conveyance device  4  can move the cultivation unit  2  in the horizontal direction and in the vertical direction. The conveyance device  4  includes a horizontally moving part  40  that is movable in the horizontal direction, and a lift  41  that is integrated with the horizontally moving part  40  and is movable in the vertical direction. The conveyance device  4  of the present embodiment conveys the discharge device  50  and the supply device  51  in addition to conveying the cultivation unit  2 . 
     In the present embodiment, the conveyance device  4  is configured by a stacker crane  42  and a plurality of conveyor devices  43 . The stacker crane  42  is installed in the cultivation room  101 , and the conveyor device  43  is installed in each of the cultivation room  101  and the work room  102 . A conveyor device  43   a  installed in the cultivation room  101  and a conveyor device  43   b  installed in the work room  102  are separate devices, and do not hinder opening and closing of the entrance  104  by the automatic door  105 . 
     As illustrated in  FIGS.  2  and  5   , the stacker crane  42  includes a traveling rail  420  installed on a floor surface of the cultivation room  101 , a frame  421  which is movable on the traveling rail  420  and has a rectangular frame shape as viewed in direction D2, and a guide rail  422  installed above the traveling rail  420  so as to guide the movement of the frame  421 . The stacker crane  42  further includes a cargo bed  423  installed in the frame  421  in a vertically movable manner, a fork device  424  provided on the cargo bed  423 , a lift device  425  that moves the cargo bed  423  vertically, and a traveling device  426  that moves the frame  421  along the traveling rail  420  and the guide rail  422 . 
     The stacker crane  42  moves the cargo bed  423  to a position adjacent to the target cultivation unit  2  stored in the storage shelf  1 , and then inserts claws  427  of the fork device  424  under the target cultivation unit  2  to lift the target cultivation unit  2 . As a result, the stacker crane  42  can move the cultivation unit  2  from the storage shelf  1  to the cargo bed  423 . Additionally, after the stacker crane  42  moves the cargo bed  423  on which the target cultivation unit  2  is placed to a position adjacent to the conveyor device  43   a  in the cultivation room  101 , the stacker crane  42  can place the target cultivation unit  2  can be placed on the conveyor device  43   a  using the fork device  424 . 
     The conveyor device  43   a  moves the cultivation unit  2  in the horizontal direction in the cultivation room  101 , that is, in directions D1 and D2. The cultivation unit  2  is transferred between the conveyor device  43   a  and the conveyor device  43   b , thereby moving between the cultivation room  101  and the work room  102 . 
     In the present embodiment, the frame  421  of the stacker crane  42  and the conveyor devices  43   a ,  43   b  form the horizontally moving part  40 , and the cargo bed  423  forms the lift  41 . The cargo bed  423  forming the lift  41  is provided integrally with the frame  421  of the horizontally moving part  40 , and moves horizontally along with the horizontal movement of the frame  421 . 
     1.2.6 Discharge/Supply Device, or Discharge Device and Supply Device 
       FIG.  1    illustrates one discharge/supply device  5  forming the discharge device  50  and the supply device  51  of the present embodiment. The discharge/supply device  5  is a device that is movable among the plurality of cultivation tanks  3  and performs both supplying and discharging of the cultivation liquid L 1  to and from the plurality of cultivation tanks  3 . In the present embodiment, the discharge/supply device  5  is conveyed by the conveyance device  4 . 
     The discharge/supply device  5  includes a nozzle  52  that discharges and supplies the cultivation liquid L 1 , a connector  53  that connects the nozzle  52  to a connection target, that is, to the cultivation tank  3  in the present embodiment, a tank  54  that stores the cultivation liquid L 1 , and a hose  55  that connects the tank  54  and the nozzle  52 . The discharge/supply device  5  further includes a pump  56  for discharging and supplying the cultivation liquid L 1 , an imaging device  57  for imaging the cultivation tank  3 , and a controller. The controller is a device that controls the connector  53 , the pump  56 , and the imaging device  57 . All of the configurations of the discharge/supply device  5 , that is, the nozzle  52 , the connector  53 , the tank  54 , the hose  55 , the pump  56 , the imaging device  57 , and the controller are installed in the lift  41  of the conveyance device  4 , that is, the cargo bed  423 . 
     The nozzle  52  includes a discharge nozzle for sucking the cultivation liquid L 1  in the cultivation tank  3 , specifically, a waste liquid L 10  in which the contained nutrients are reduced, and a supply nozzle for ejecting the cultivation liquid L 1 , specifically, a nourishing liquid L 11  containing nutrients into the cultivation tank  3 . The nozzle  52  may be configured by one nozzle and be switchable between suction and ejection. 
     In the present embodiment, the connector  53  is an articulated robot arm that supports the nozzle  52  and freely moves the nozzle  52  in the horizontal direction, that is, in direction D1 and direction D2, and in the vertical direction, that is, in direction D3. The robot arm can also rotate about an axis parallel to the vertical direction, that is, direction D3, and can connect the nozzle  52  to each of the cultivation tanks  3  of the cultivation units  2  in the pair of storage shelves  1  positioned across the passage from each other. 
     The connector  53  can move the nozzle  52  between an insertion position and a standby position. The insertion position is a position where the nozzle  52  is inserted into the through hole  311  of the planting panel  31  of the cultivation tank  3 . The standby position is a position where the nozzle  52  is separated from the through hole  311 . The connector  53  is installed on the tank  54 . 
     The tank  54  includes a tank body  540  that stores the cultivation liquid L 1 , four columns  545  that support the tank body  540 , a bottom plate  546  that is separated from and below the tank body  540  and supported by lower ends of the four columns  545 , and a plurality of legs  541  protruding downward from lower surfaces of the four columns  545 . 
     The tank body  540  includes a waste liquid reservoir  542  that stores the cultivation liquid L 1  sucked from the inside of cultivation tank  3 , that is, the waste liquid L 10 , a nourishing liquid reservoir  543  that stores a new cultivation liquid L 1  to be supplied to the cultivation tank  3 , that is, the nourishing liquid L 11 , and a partition wall  544 . The partition wall  544  separates the waste liquid reservoir  542  and the nourishing liquid reservoir  543 . Half of the internal space of the tank body  540  is the waste liquid reservoir  542 , and the remaining half of the tank body  540  is the nourishing liquid reservoir  543 . While the storages  542 ,  543  are positioned side by side in direction D2 in the present embodiment, the storages  542 ,  543  may be positioned side by side in direction D1 or direction D3. 
     The components of the cultivation liquid L 1  stored in the nourishing liquid reservoir  543 , that is, the nourishing liquid L 11  are appropriately set in accordance with the growth stage of the plant P 1  or the type of the plant P 1 . The cultivation liquid L 1 , that is, the nourishing liquid L 11  contains dissolved oxygen. A circulation pump (not illustrated) is installed in the nourishing liquid reservoir  543 , and the cultivation liquid L 1 , that is, the nourishing liquid L 11  is maintained in the state containing dissolved oxygen. 
     The capacity of the tank  54  is 1200 liters, for example. In this case, the waste liquid reservoir  542  can store, for example, 600 liters of the cultivation liquid L 1 , that is, the waste liquid L 10 , and the nourishing liquid reservoir  543  can store, for example, 600 liters of a new cultivation liquid L 1 , that is, the nourishing liquid L 11 . In this case, the tank  54  enables replacement of all cultivation liquids L 1  in a plurality of cultivation tanks  3  of five cultivation units  2 . 
     The shape of the bottom of the tank  54  is the same as the shape of the bottom of the cultivation unit  2 . Hence, the claws  427  of the fork device  424  of the stacker crane  42  can be inserted between the plurality of legs  541  below the bottom plate  546  of the tank  54 . As a result, the tank  54  can be moved between the cargo bed  423  and the conveyor device  43   a  using the fork device  424 . 
     The hose  55  includes a discharge hose  550  that connects the discharge nozzle of the nozzle  52  and the waste liquid reservoir  542  of the tank  54 , and a supply hose  551  that connects the supply nozzle of the nozzle  52  and the nourishing liquid reservoir  543  of the tank  54 . The downstream end of the discharge hose  550  is connected to an upper part of the waste liquid reservoir  542 , and the upstream end of the supply hose  551  is connected to a bottom part of the nourishing liquid reservoir  543 . 
     The pump  56  includes a discharge pump  560  connected to the discharge hose  550  and a supply pump  561  connected to the supply hose  551 . In the present embodiment, the discharge pump  560  is a vacuum pump, for example. The discharge pump  560  may be provided integrally with the discharge nozzle. In the present embodiment, the supply pump  561  is installed on the bottom plate  546  and is connected to the upstream end of the supply hose  551 . 
     By driving the discharge pump  560 , the cultivation liquid L 1  in the cultivation tank  3 , that is, the waste liquid L 10  can be sucked by the discharge nozzle and be sent to the waste liquid reservoir  542  of the tank  54 . Additionally, by driving the supply pump  561 , the cultivation liquid L 1  in the nourishing liquid reservoir  543 , that is, the nourishing liquid L 11  can be ejected from the supply nozzle and be supplied to the cultivation tank  3 . 
     The imaging device  57  is a device that images the cultivation tank  3 , and is a camera, for example. The imaging device  57  is installed in the lift  41  of the conveyance device  4 , and thus can move in the vertical direction and in the horizontal direction. In the present embodiment, the imaging device  57  is installed on the connector  53 . 
     The imaging device  57  images the plant P 1  held in the cultivation tank  3  as a still image or a moving image, and transmits the imaging data to a display device such as a monitor installed in the work station A 1 . As a result, in the work station A 1 , it is possible to remotely check the growth state of the plant P 1  in each cultivation tank  3 . 
     The controller includes, for example, a computer including a processor such as a central processing unit (CPU) and a memory. The computer includes a microcomputer. The controller controls each of the connector  53 , the pump  56 , and the imaging device  57  by executing an appropriate program stored in the memory. 
     The discharge/supply device  5  of the present embodiment further includes a sensor that detects the position of the through hole  311  of the planting panel  31  of each of the cultivation tanks  3 . As the sensor, a known sensor can be used. The controller controls the connector  53  on the basis of the detection result of the sensor to adjust the position of the nozzle  52 . 
     1.2.7 Others 
     The cultivation equipment of the present embodiment further includes a treatment apparatus  6  illustrated in  FIG.  6   . The treatment apparatus  6  is an apparatus that treats the cultivation liquid L 1  discharged from the tank  54  of the discharge/supply device  5 , that is, the waste liquid L 10 . 
     The treatment apparatus  6  includes a receiving member  60  that receives the cultivation liquid L 1  discharged from the tank  54 , that is, the waste liquid L 10 , a contaminant separator  61  that removes contaminants in the cultivation liquid L 1 , that is, the waste liquid L 10 , and a filter  62  that filters the cultivation liquid L 1 , that is, the waste liquid L 10 . The treatment apparatus  6  further includes a sterilizer  63  that sterilizes the filtered cultivation liquid L 1 , that is, the waste liquid L 10  to obtain a treated liquid L 2 , and a treated liquid tank  64  that stores the treated liquid L 2 . 
     The receiving member  60  is a hopper including a vertically inverted pyramid-shaped container, for example. For example, by driving the pump  56  of the discharge/supply device  5  to eject the cultivation liquid L 1  stored in the waste liquid reservoir  542  of the tank  54 , that is, the waste liquid L 10  from the nozzle  52  to the receiving member  60 , the cultivation liquid L 1 , that is, the waste liquid L 10  is supplied to the receiving member  60 . The method for discharging the cultivation liquid L 1 , that is, the waste liquid L 10  from the waste liquid reservoir  542  of the tank  54  to the receiving member  60  is not limited to the method using a pump. 
     The contaminant separator  61  is positioned on the downstream side of the receiving member  60 , that is, on the lower side in the present embodiment. The contaminant separator  61  is a device that receives the cultivation liquid L 1  that has passed through the receiving member  60  and removes contaminants such as roots and leaves of the plant P 1  in the cultivation liquid L 1 . The contaminant separator  61  includes a container  610  for receiving the cultivation liquid L 1  and meshes  611 ,  612  detachably installed in the container  610 . The mesh  612  positioned on the lower side is finer than the mesh  611  positioned on the upper side. 
     The filter  62  is positioned downstream of the contaminant separator  61 , that is, on the lower side in the present embodiment. The filter  62  receives the cultivation liquid L 1  that has passed through the contaminant separator  61 , and filters the cultivation liquid L 1 . As a result, the filter  62  can remove fine contaminants remaining in the cultivation liquid L 1 . 
     The sterilizer  63  is positioned downstream of the filter  62 . The sterilizer  63  sterilizes the cultivation liquid L 1  that has passed through the filter  62  to obtain a treated liquid L 2 . The sterilizer  63  sterilizes the cultivation liquid L 1  using nanobubbles, for example. 
     The treated liquid tank  64  is positioned downstream of the sterilizer  63  and stores the treated liquid L 2 . The treated liquid L 2  stored in the treated liquid tank  64  can be reused as the cultivation liquid L 1 , that is, the nourishing liquid L 11  by adding nutrients and oxygen to the treated liquid L 2 . 
     The treatment apparatus  6  is installed in the work room  102  of the cultivation building  100 . For example, the treatment apparatus  6  is installed so as to extend over the work room  102  on each floor. For example, the cultivation liquid L 1  is naturally dropped using the weight of the cultivation liquid L 1  to be moved from the receiving member  60  to the treated liquid tank  64 . In this case, since the treatment apparatus  6  does not require a pump, the manufacturing cost can be suppressed. 
     In the cultivation equipment of the present embodiment, the discharge/supply device  5  sucks the cultivation liquid L 1  in the cultivation tank  3 , and every time the waste liquid reservoir  542  of the tank  54  is filled with the cultivation liquid L 1 , that is, the waste liquid L 10 , the discharge/supply device  5  is conveyed to the work room  102 , and the treatment apparatus  6  treats the cultivation liquid L 1 , that is, the waste liquid L 10 . As a result, in the cultivation equipment of the present embodiment, a large treatment apparatus provided in a conventional plant factory becomes unnecessary. 
     1.2.8 Cultivation Method 
     Next, a cultivation method for cultivating the plant P 1  using the above-described cultivation equipment will be described. 
     The cultivation method includes carry-in step S 1 , cultivation step S 2 , pre-carry-out discharge step S 3 , carry-out step S 4 , and work step S 5 . 
     Carry-in step S 1  is a step of storing the plurality of cultivation units  2  in which the plurality of cultivation tanks  3  holding the plants P 1  and the cultivation liquid L 1  are installed in the storage shelf  1  using the conveyance device  4 . At this time, a plurality of cultivation tanks  3  not containing the cultivation liquid L 1 , that is, the nourishing liquid L 11  are installed on each support plate  20  of the cultivation unit  2 . In carry-in step S 1 , the cultivation liquid L 1  is not contained in the plurality of cultivation tanks  3  of the cultivation unit  2 . Accordingly, the cultivation liquid L 1  does not spill from each of the cultivation tanks  3  at the time of conveyance, so that the conveyance speed can be increased and conveyance efficiency can be enhanced. 
     Cultivation step S 2  is a step of cultivating plants P 1  in the plurality of cultivation tanks  3  of the plurality of cultivation units  2  stored in the storage shelf  1 . Cultivation step S 2  includes supply step S 20  of supplying the cultivation liquid L 1 , that is, the nourishing liquid L 11  to the plurality of cultivation tanks  3  of the plurality of cultivation units  2 , and discharge step S 21  of discharging the cultivation liquid L 1 , that is, the waste liquid L 10  from the plurality of cultivation tanks  3  of the plurality of cultivation units  2 . 
     In supply step S 20 , the stacker crane  42  of the conveyance device  4  moves the discharge/supply device  5  to the vicinity of the target cultivation unit  2 . Next, the connector  53  of the discharge/supply device  5  moves the nozzle  52  to insert the tip end of the nozzle  52  into the through hole  311  of the planting panel  31  of the cultivation tank  3  of the target cultivation unit  2 . Next, the pump  56  of the discharge/supply device  5 , specifically, the supply pump  561  is driven to eject the cultivation liquid L 1  in the nourishing liquid reservoir  543 , that is, the nourishing liquid L 11  from the nozzle  52 , and store a predetermined amount of the cultivation liquid L 1 , that is, the nourishing liquid L 11  in the tray  30  of the cultivation tank  3  of the target cultivation unit  2 . In supply step S 20 , the cultivation liquid L 1  is supplied to all of the plurality of cultivation tanks  3  of the target cultivation unit  2  in the above-described manner. 
     Discharge step S 21  is a step of discharging the cultivation liquid L 1 , that is, the waste liquid L 10  in which the contained nutrients are reduced, from the cultivation tank  3  of the target cultivation unit  2 . In discharge step S 21 , as in supply step S 20 , the tip end of the nozzle  52  is inserted into the through hole  311  of the planting panel  31  of the cultivation tank  3  of the target cultivation unit  2 . Next, the pump  56  of the discharge/supply device  5 , specifically, the discharge pump  560  is driven to suck the cultivation liquid L 1  in the tray  30 , that is, the waste liquid L 10  through the nozzle  52  and send the waste liquid L 10  to the waste liquid reservoir  542  of the tank  54 . In discharge step S 21 , the cultivation liquid L 1 , that is, the waste liquid L 10  is discharged from all of the plurality of cultivation tanks  3  of the target cultivation unit  2  in the above-described manner. 
     In cultivation step S 2 , after supply step S 20  is performed once, a set of discharge step S 21  and supply step S 20  is repeatedly performed according to the growth rate of the plant P 1 . This set is performed for the target cultivation unit  2  every other week, for example. 
     In cultivation step S 2 , when the waste liquid reservoir  542  of the tank  54  of the discharge/supply device  5  is filled with the cultivation liquid L 1 , that is, the waste liquid L 10 , or the cultivation liquid L 1  in the nourishing liquid reservoir  543 , that is, the nourishing liquid L 11  is used up, or both, the discharge/supply device  5  is conveyed from the cultivation room  101  to the work room  102  by the conveyance device  4 . In the work room  102 , at least one of discharge of the cultivation liquid L 1  in the waste liquid reservoir  542  of the tank  54 , that is, the waste liquid L 10  to the treatment apparatus  6  and supply of the cultivation liquid L 1 , that is, the nourishing liquid L 11  to the nourishing liquid reservoir  543  is performed. 
     In cultivation step S 2 , power is supplied from the power transmitter  12  of the storage shelf  1  to the power receiver  23  of each cultivation unit  2 . As a result, the LED lamps  220  of the irradiation devices  22  of each cultivation unit  2  irradiate the plurality of plants P 1  held by the plurality of cultivation tanks  3  of each cultivation unit  2  with grow light, and the cultivation of the plants P 1  is promoted in each cultivation tank  3  in which the cultivation liquid L 1  is stored. 
     In the present embodiment, cultivation step S 2  includes checking step S 22  of checking the growth state of the plant P 1  imaged by the imaging device  57 . In supply step S 20  and discharge step S 21 , the plant P 1  held in the cultivation tank  3  of the target cultivation unit  2  is imaged by the imaging device  57 . The still image or moving image captured by the imaging device  57  is transmitted to the display device of the work station A 1 , and can be checked in the work station A 1 . 
     Pre-carry-out discharge step S 3  is a step of discharging the cultivation liquid L 1  from all of the plurality of cultivation tanks  3  installed in the target cultivation unit  2 . Pre-carry-out discharge step S 3  is performed after supply step S 20 . 
     Specifically, in pre-carry-out discharge step S 3 , the cultivation liquid L 1  is discharged from all of the plurality of cultivation tanks  3  of the target cultivation unit  2  by the same method as discharge step S 21  described above. The cultivation liquid L 1  discharged at this time is not limited to the waste liquid L 10  in which the contained nutrients are reduced, and may be the nourishing liquid L 11  containing a large amount of nutrients. 
     Carry-out step S 4  is performed after pre-carry-out discharge step S 3 . Carry-out step S 4  is a step of carrying out the target cultivation unit  2  from which the cultivation liquid L 1  is discharged from the storage shelf  1  to the work station A 1  using the conveyance device  4 . 
     Specifically, in carry-out step S 4 , the target cultivation unit  2  is removed from the storage shelf  1  by the stacker crane  42  of the conveyance device  4 . The target cultivation unit  2  is conveyed to the conveyor device  43   a  in the cultivation room  101  by the stacker crane  42 , and is placed on the conveyor device  43   a . The target cultivation unit  2  is conveyed by the conveyor device  43   a  in the cultivation room  101 , and is delivered to the conveyor device  43   b  in the work room  102 . At this time, the automatic door  105  of the wall  103  of the cultivation building  100  opens automatically. When the entire target cultivation unit  2  is placed on the conveyor device  43   b  in the work room  102 , the automatic door  105  automatically closes the entrance  104 . 
     In carry-out step S 4 , the cultivation liquid L 1  is substantially not contained in the plurality of cultivation tanks  3  of the cultivation unit  2 . Accordingly, spillage of the cultivation liquid L 1  from each of the cultivation tanks  3  during conveyance of the cultivation tanks  3  can be curbed, so that the conveyance speed can be increased and conveyance efficiency can be enhanced. Additionally, in carry-out step S 4 , the cultivation liquid L 1  that has adhered to a root part of the plant P 1  held by the planting panel  31  of each of the cultivation tanks  3  can be dropped onto the tray  30  by vibration during conveyance. 
     Work step S 5  is a step of performing various works on the plurality of cultivation tanks  3  of the target cultivation unit  2  conveyed to the work station A 1 . 
     In work step S 5 , for example, the plants P 1  held in the plurality of cultivation tanks  3  of the target cultivation unit  2  are harvested. At this time, for example, the boundary between a leaf part and a root part of the plant P 1  is cut, and only the leaf part is harvested. In the present embodiment, the cultivation liquid L 1  is substantially not contained in each of the cultivation tanks  3  at the time of conveyance of the cultivation unit  2 . Hence, it is possible to prevent the cultivation liquid L 1  from splashing onto the leaf part at the time of conveyance, and to prevent an increase in the amount of water required for cleaning the leaf part of the plant P 1 . 
     In the cultivation tank  3  in which the harvest of the leaf part of the plant P 1  is completed, the planting panel  31  is removed from the tray  30 , the cut root part of the plant P 1  and the remaining cultivation liquid L 1  are taken out of the tray  30 , and the tray  30  and the planting panel  31  are cleaned. As a result, the tray  30  and the planting panel  31  can be reused. 
     In addition, in work step S 5 , a work of inspecting the growth degree of the plant P 1  held in the plurality of cultivation tanks  3  of the target cultivation unit  2  and a work of replacing the planting panel  31  included in the plurality of cultivation tanks  3  of the target cultivation unit  2  with another planting panel  31  are performed. 
     1.2.9 Action and Effect 
     The cultivation equipment of the present embodiment described above includes the discharge/supply device  5 , namely, the discharge device  50  and the supply device  51  in the present embodiment, that is movable in the cultivation room  101  and can supply and discharge the cultivation liquid L 1  to and from the plurality of cultivation tanks  3  of the plurality of cultivation units  2  in the storage shelf  1 . 
     For this reason, in the cultivation equipment of the present embodiment, there is no need to install a large number of pipes or a large pump for supply or discharge of the cultivation liquid L 1  in the storage shelf  1 , and it is possible to prevent complication and upsizing of the equipment. Accordingly, in the cultivation equipment of the present embodiment, the storage shelf  1  is easily increased in height, and the harvest amount per unit area is easily increased. 
     Additionally, in the cultivation equipment of the present embodiment, when the cultivation unit  2  is conveyed between the storage shelf  1  and the work station A 1  by the conveyance device  4 , a plurality of cultivation tanks  3  of the cultivation unit  2  can be kept in a state where the cultivation tanks  3  do not contain or substantially do not contain the cultivation liquid L 1 . 
     Hence, in the cultivation equipment of the present embodiment, the weight of the cultivation unit  2  at the time of conveyance can be curbed, and the load applied to the conveyance device  4  can be curbed. Additionally, in the cultivation equipment of the present embodiment, there is no risk of liquid leakage when the cultivation unit  2  is conveyed by the conveyance device  4 . Hence, the speed of conveyance of the cultivation unit  2  by the conveyance device  4  can be increased, and the harvest amount per unit time can be improved. 
     Additionally, in the cultivation equipment of the present embodiment, liquid leakage from each cultivation tank  3  of the cultivation unit  2  at the time of conveyance can be prevented, so that it is possible to curb contamination of each of the storage shelf  1 , the cultivation unit  2 , the conveyance device  4 , and the conveyance passage with the cultivation liquid L 1 . 
     Additionally, in the cultivation equipment of the present embodiment, since the discharge/supply device  5  can be moved by the conveyance device  4  that conveys the cultivation unit  2 , a separate device for moving the discharge/supply device  5  is not required, and equipment cost can be kept low. 
     Additionally, in the cultivation equipment of the present embodiment, the discharge device  50  that discharges the cultivation liquid L 1  and the supply device  51  that supplies the cultivation liquid L 1  are configured by one discharge/supply device  5 . Hence, the cultivation liquid L 1  can be replaced collectively for the cultivation tanks  3  in the cultivation unit  2 , and workability can be improved. 
     Additionally, in the cultivation equipment of the present embodiment, the number of times of conveyance of the cultivation units  2  can be reduced as compared with a case where the cultivation units  2  are repeatedly conveyed between the storage shelf  1  and the work station A 1  for replacement of the cultivation liquid L 1 . 
     1.3 Modification 
     Next, modifications of the cultivation equipment of the present embodiment will be described. The following modifications can be appropriately combined. 
     The discharge device  50  and the supply device  51  do not need to be configured by one discharge/supply device  5 , and may be separate devices. In this case, each of the discharge device  50  and the supply device  51  have a structure common to the discharge/supply device  5 . That is, the discharge device  50  includes a part corresponding to the discharge nozzle of the nozzle  52 , the connector  53 , a part corresponding to the waste liquid reservoir  542  of the tank  54 , a part corresponding to the discharge hose  550  of the hose  55 , a part corresponding to the discharge pump  560  of the pump  56 , the imaging device  57 , and the controller. The supply device  51  includes a part corresponding to the supply nozzle of the nozzle  52 , the connector  53 , a part corresponding to the nourishing liquid reservoir  543  of the tank  54 , a part corresponding to the supply hose  551  of the hose  55 , a part corresponding to the supply pump  561  of the pump  56 , the imaging device  57 , and the controller. 
     The discharge/supply device  5  may be conveyed not by the conveyance device  4  but by a device different from the conveyance device  4 . Additionally, in a case where the discharge device  50  and the supply device  51  are provided separately, the discharge device  50  and the supply device  51  may be conveyed by devices different from the conveyance device  4 . 
     Additionally, the conveyance device  4  is not limited to the combination of the stacker crane  42  and the conveyor devices  43   a ,  43   b  described above. The conveyance device  4  may include, for example, a suspension-type conveyance device instead of the stacker crane  42 . Additionally, the conveyance device  4  does not need to include the conveyor device  43   a  installed in the cultivation room  101 , and the stacker crane  42  may convey the cultivation units  2  between the storage shelf  1  and the conveyor device  43   b.    
     Additionally, the cultivation equipment does not need to include the imaging device  57 , and the growth state of the plant P 1  may be checked when the cultivation unit  2  is conveyed to the work station A 1 . 
     Additionally, the imaging device  57  may be any device as long as the device is installed in the lift  41  and images the plurality of cultivation tanks  3 , and the installation position of the imaging device  57  is not limited to the position on the connector  53 , and may be other positions. 
     The cultivation unit  2  is not limited to the structure described above. For example, as in Modification  1  illustrated in  FIG.  7   , the cultivation unit  2  may further include a guide member  24  that guides insertion of the nozzle  52  into the through hole  311  of the planting panel  31  of each cultivation tank  3 . The guide member  24  is fixed to one side in direction D1 of the support plate  20  of each stage, specifically, an end surface on the conveyance passage side. The cultivation unit  2  includes two guide members  24 . The two guide members  24  are spaced apart in direction D1. The two guide members  24  are arranged so as to correspond to positions of two cultivation tanks  3  arranged on the support plate  20 . 
     Specifically, the guide member  24  includes a plate-shaped main body  240  extending in direction D3, a plurality of through holes  241  provided in the main body  240 , and a water receiving container  242  in which a lower part of the main body  240  is accommodated. Both ends of the main body  240  in direction D1 are inclined with respect to a central part in direction D1, and the gap between the both ends increases toward end edges of the main body  240  in direction D1. 
     A plurality of through holes  241  are formed at intervals in direction D3 in the central part of the main body  240  in direction D1. The plurality of through holes  241  are arranged so as to have a predetermined positional relationship with respect to the through holes  311  of the planting panels  31  of the cultivation tanks  3  installed on the support plates  20  of the stages of the cultivation unit  2 . The water receiving container  242  receives liquid leakage at the time of insertion or removal of the nozzle  52 . 
     For example, when the through hole  241  is detected by a sensor, the controller of the discharge/supply device  5  controls the position of the nozzle  52  such that the nozzle  52 , the through hole  241 , and the through hole  311  of the planting panel  31  are positioned on a straight line. Next, by moving the nozzle  52  linearly, the controller can insert the nozzle  52  through the through hole  241  of the guide member  24  and the through hole  311  of the planting panel  31 , and into the tray  30 . 
     Alternatively, as in Modification  2  illustrated in  FIGS.  8 A and  8 B , the cultivation unit  2  may include: a first unit  25  having a plurality of support plates  20  arranged at intervals in direction D3, that is, in the vertical direction; and a second unit  26  that can be combined with the first unit  25  and has a plurality of irradiation devices  22 . 
     The first unit  25  has substantially the same structure as the cultivation unit  2  of Embodiment 1, and does not include the plurality of irradiation devices  22  and the power receiver  23 . That is, the first unit  25  includes a plurality of, to be more specific, five support plates  20  arranged at intervals in direction D3, and a plurality of, to be more specific, four columns  21  supporting the plurality of support plates  20 . Each of the plurality of support plates  20  has a flat rectangular box shape opened to the lower side and to the side, that is, to one side in direction D2. 
     The second unit  26  includes two columns  260  positioned at an interval in direction D1, a plurality of coupling members  261  bridged across the two columns  260  and arranged at intervals in direction D3, and a plurality of support members  262  fixed two by two to each of the plurality of coupling members  261 . The two support members  262  of each stage have one ends fixed to the coupling member  261 , and are disposed along direction D2 at an interval. The irradiation device  22  is bridged across and supported by the two support members  262  of each stage. The two support members  262  of each stage are configured to support the irradiation device  22  at a height corresponding to each of the plurality of support plates  20  of the first unit  25  except the lowermost support plate  20 . 
     The second unit  26  includes a power cord  263  connected to the plurality of irradiation devices  22 . The power cord  263  is mechanically and electrically connected to a power supply device (not illustrated) such as a power supply cord and an outlet provided on the storage shelf  1 . 
     The second unit  26  is fixed to the storage shelf  1  with appropriate fixing means to be installed in a standing state on the shelf member  10 . The second unit  26  may be provided on the shelf member  10  of the storage shelf  1  in a self-supporting manner. 
     In a state where the first unit  25  and the second unit  26  are combined, the irradiation devices  22  of each stage of the second unit  26  are disposed on the support plate  20  of each stage of the first unit  25 . When the first unit  25  is carried into the storage shelf  1  by the conveyance device  4 , the first unit  25  is conveyed to a position where it is combined with the second unit  26 . 
     The first unit  25  and the second unit  26  can be integrated by connecting the columns  21 ,  260  with a fixing tool such as a bolt and a nut in a state where the columns  21 ,  260  are placed to overlap each other in direction D2. By integrating the first unit  25  and the second unit  26  in this manner, the first unit  25  and the second unit  26  can be conveyed together using the conveyance device  4 . 
     In the cultivation unit  2  of Modification  2 , it is possible to convey only the first unit  25  of the cultivation unit  2  by the conveyance device  4 , and the second unit  26  including the irradiation device  22  can be left in the storage shelf  1 . For this reason, in the cultivation unit  2  of Modification  2 , a structure for performing wireless power transfer as in the cultivation unit  2  of Embodiment 1 is unnecessary. Hence, it is possible to curb occurrence of trouble at the time of power supply and to curb the manufacturing cost. 
     Additionally, in the cultivation unit  2  of Modification  2 , the plurality of irradiation devices  22  can be collectively installed in the storage shelf  1  only by fixing the second unit  26  in which the plurality of irradiation devices  22  are installed to the storage shelf  1 . Thus, it is possible to omit the work of installing the irradiation devices  22  one by one in the storage shelf  1 . 
     Additionally, the discharge/supply device  5  is not limited to the structure described above. For example, the discharge/supply device  5  may include a plurality of nozzles  52 , more specifically, the same number of nozzles  52  as the number of the plurality of cultivation tanks  3  installed in one cultivation unit  2 , and may simultaneously replace the cultivation liquid L 1  in the plurality of cultivation tanks  3  installed in one cultivation unit  2 . 
     Alternatively, as in Modification  3  illustrated in  FIG.  9   , the cultivation unit  2  may further include a unit tank  27 , a supply pipe  28 , and a discharge pipe  29  in addition to the configuration of the cultivation unit  2  of Embodiment 1. 
     The unit tank  27  is a tank for storing the cultivation liquid L 1 . The supply pipe  28  connects unit tank  27  and the plurality of cultivation tanks  3 , and supplies the cultivation liquid L 1  in the unit tank  27  to the plurality of cultivation tanks  3 . The discharge pipe  29  connects the unit tank  27  and the plurality of cultivation tanks  3 , and discharges the cultivation liquid L 1  in the plurality of cultivation tanks  3  to the unit tank  27 . 
     In the present embodiment, the connection target of the connector  53  is the unit tank  27 . The unit tank  27  is installed on the lowermost support plate  20  of the plurality of support plates  20  of the cultivation unit  2 . The unit tank  27  has a discharge/supply port  270 . The discharge/supply port  270  connects the internal space of the unit tank  27  where the cultivation liquid L 1  is stored and the external space of the unit tank  27 . The nozzle  52  of the discharge/supply device  5  is inserted into the discharge/supply port  270 . 
     The supply pipe  28  connects each of the plurality of cultivation tanks  3  and the unit tank  27 . The supply pipe  28  includes, for example, a linear main pipe  280 , a plurality of L-shaped connection pipes  281  communicating with the main pipe  280 , and a coupling pipe  282  communicating with the main pipe  280  and the unit tank  27 . A pump  283  is connected to the coupling pipe  282 . The pump  283  is installed on the lowermost support plate  20  of the plurality of support plates  20  of the cultivation unit  2 . The number of the connection pipes  281  is equal to the number of the plurality of cultivation tanks  3  installed in the cultivation unit  2 . Downstream ends of the plurality of connection pipes  281  are inserted one-to-one into the through holes  311  of the planting panels  31  of the plurality of cultivation tanks  3 . By driving the pump  283 , the cultivation liquid L 1  in the unit tank  27  is supplied into the plurality of cultivation tanks  3  through the plurality of connection pipes  281 , respectively. 
     The discharge pipe  29  connects each of the plurality of cultivation tanks  3  and the unit tank  27 . In the present embodiment, the discharge pipe  29  is a pipe thicker than the supply pipe  28 . The discharge pipe  29  includes, for example, a linear main pipe  290 , a plurality of L-shaped connection pipes  291  communicating with the main pipe  290 , and a coupling pipe  292  communicating with the lowermost connection pipe  291  and the unit tank  27 . The number of the connection pipes  291  is equal to the number of the plurality of cultivation tanks  3  installed in the cultivation unit  2 . 
     Upstream ends of the plurality of connection pipes  291  are connected to discharge ports  300  formed in bottom walls of the trays  30  of the plurality of cultivation tanks  3 . The discharge port  300  is positioned at an end of the cultivation tank  3  opposite to the through hole  311 . An upstream end, that is, an upper end of each connection pipe  291  is positioned at a predetermined height, such as 50 mm, from a bottom surface of the tray  30  of the corresponding cultivation tank  3 . The height is appropriately set according to the type and the like of the plant P 1  to be cultivated. The cultivation liquid L 1  can be stored in the tray  30  up to the height of the upper end of the connected connection pipe  291 . The cultivation liquid L 1  that exceeds the height of the upper end of the connection pipe  291  flows into the upper end opening of the connection pipe  291 , and is discharged to the unit tank  27 . That is, a part of each connection pipe  291  positioned in the tray  30 , that is, an upstream end forms an overflow pipe. 
     Additionally, at least one discharge hole is provided in a lowermost part of the part of each connection pipe  291  positioned in the tray  30 . The cultivation liquid L 1  in the tray  30  is constantly discharged to the unit tank  27  through the discharge hole. 
     In the cultivation unit  2  of Modification  3 , while the cultivation liquid L 1  in the unit tank  27  is supplied to each of the plurality of cultivation tanks  3  through the supply pipe  28 , the cultivation liquid L 1  in the plurality of cultivation tanks  3  is discharged into the unit tank  27  through the discharge pipe  29 . As a result, in the plurality of cultivation tanks  3 , a state where the cultivation liquid L 1  is stored up to the height of the upper end of the connection pipe  291  connected to each cultivation tank  3  can be maintained. 
     When the supply of the cultivation liquid L 1  through the supply pipe  28  is stopped, all or substantially all of the cultivation liquid L 1  in the tray  30  of each of the cultivation tanks  3  is discharged to the unit tank  27  through the discharge hole of the corresponding connection pipe  291 , whereby each of the cultivation tanks  3  can be brought into a state where the cultivation tank  3  does not contain or substantially does not contain the cultivation liquid L 1 . 
     In the cultivation unit  2  of Modification  3 , the nozzle  52  of the discharge/supply device  5  is connected to the discharge/supply port  270  of the unit tank  27 . The discharge/supply device  5  discharges the cultivation liquid L 1  in the unit tank  27 , that is, the waste liquid L 10 , and supplies a new cultivation liquid L 1 , that is, the nourishing liquid L 11  into the unit tank  27 . The replacement, that is, the discharge and supply of the cultivation liquid L 1  by the discharge/supply device  5  is performed every period, such as every week, in which it is estimated that the contained nutrients of the cultivation liquid L 1  in the unit tank  27  have decreased to a predetermined value or less. 
     In the cultivation unit  2  of Modification  3  described above, there is no need to connect the nozzle  52  of the discharge/supply device  5  to each of the plurality of cultivation tanks  3 . Hence, it is possible to shorten the time required for discharging and supplying the cultivation liquid L 1 . 
     Additionally, in the cultivation unit  2  of Modification  3 , relatively thin pipes corresponding to the number of the plurality of cultivation tanks  3  installed in one cultivation unit  2  can be used as the supply pipe  28  and the discharge pipe  29 , and a pump having a relatively small capacity can be used as the pump  283 . For this reason, in the cultivation equipment including the cultivation unit  2  of Modification  3 , upsizing of the equipment can be curbed as compared with a case where a thick pipe or a large-capacity pump is provided in the storage shelf  1  as in the conventional example. 
     Additionally, since the cultivation unit  2  of Modification  3  can be conveyed between the storage shelf  1  and the work station A 1  by the conveyance device  4 , maintenance of the unit tank  27 , the supply pipe  28 , the discharge pipe  29 , the pump  283 , and the like can be performed easily. 
     Additionally, in the cultivation unit  2  of Modification  3 , when the cultivation unit  2  is conveyed by the conveyance device  4 , the plurality of cultivation tanks  3  and the unit tank  27  can be brought into a state where the cultivation tanks  3  and the unit tank  27  do not contain or substantially do not contain the cultivation liquid L 1 . 
     Thus, liquid leakage at the time of conveyance can be curbed. 
     2. Embodiment 2 
     Next, cultivation equipment of Embodiment 2 illustrated in  FIGS.  10  to  14    will be described. 
     Hereinafter, regarding the cultivation equipment of Embodiment 2, configurations common to the cultivation equipment of Embodiment 1 will be denoted by the same reference numerals in the drawings and detailed description thereof will be omitted, and configurations different from the cultivation equipment of Embodiment 1 will be described in detail. 
     2.1 Details 
     The cultivation equipment of Embodiment 2 includes a discharge device  50  illustrated in  FIGS.  10  to  12    and a supply device  51  illustrated in  FIGS.  13  and  14   . The discharge device  50  and the supply device  51  are not configured by one discharge/supply device  5 , but are separate devices. 
     As illustrated in  FIG.  12   , a part of the structure of the discharge device  50  is the same as the structure of the discharge/supply device  5  of Embodiment 1. The discharge device  50  includes a nozzle  52   a  that discharges a cultivation liquid L 1 , more specifically, a waste liquid L 10 , a connector  53   a  that connects the nozzle  52   a  to a connection target, a tank  54   a  that stores the cultivation liquid L 1 , and a hose  55   a  that connects the tank  54   a  and the nozzle  52   a . The discharge device  50  further includes a pump  56   a  for sucking the cultivation liquid L 1 , more specifically, the waste liquid L 10 , an imaging device  57   a  for imaging a cultivation tank  3 , and a controller (not illustrated) for controlling each of the connector  53   a , the pump  56   a , and the imaging device  57   a . The discharge device  50  further includes a winder  58   a  that automatically winds up the hose  55   a , and a base  59   a . All components of the discharge device  50  except the tank  54   a  and the base  59   a , that is, the nozzle  52   a , the connector  53   a , the hose  55   a , the pump  56   a , the imaging device  57   a , the winder  58   a , and the controller are installed on the base  59   a  to form a nozzle unit. 
     The nozzle  52   a , the connector  53   a , the tank  54   a , the hose  55   a , the pump  56   a , the imaging device  57   a , and the controller of the discharge device  50  have the same structure as the discharge nozzle of the nozzle  52 , the connector  53 , the part of the tank  54  corresponding to the waste liquid reservoir  542 , the discharge hose  550 , the discharge pump  560 , the imaging device  57 , and the controller of the discharge/supply device  5  of Embodiment 1. 
     The winder  58   a  includes, for example, a drum around which the hose  55   a  is wound, and biasing means for rotating the drum in a direction in which the hose  55   a  is wound. The hose  55   a  can be pulled out of the winder  58   a  against the biasing force of the biasing means. 
     A stacker crane  42  included in a conveyance device  4  further includes a nozzle installation part  428  and a tank installation part  429 . The nozzle installation part  428  is integrated with a cargo bed  423 , and is lifted and lowered together with the cargo bed  423  outside a frame  421 . The tank installation part  429  is integrated with the bottom of the frame  421 , is positioned outside the frame  421 , and travels on a traveling rail  420 . The nozzle installation part  428  is positioned above the tank installation part  429 . The nozzle installation part  428  forms a lift  41  together with the cargo bed  423 . The tank installation part  429  forms a horizontally moving part  40  together with the frame  421 . In  FIGS.  10  to  12   , illustration of a lift device  425  is omitted. 
     The nozzle unit of the discharge device  50  is detachably installed in the nozzle installation part  428 , that is, the lift  41 . The tank  54   a  of the discharge device  50  is detachably installed in the tank installation part  429 , that is, the horizontally moving part  40 . The nozzle installation part  428  is provided with a fork device (not illustrated) similarly to the cargo bed  423 . The fork device provided in the nozzle installation part  428  is smaller than a fork device  424  provided in the cargo bed  423 . With this fork device, the nozzle unit of the discharge device  50  can be placed on and off the nozzle installation part  428 . 
     When the stacker crane  42  moves the nozzle unit of the discharge device  50  in the horizontal direction and the vertical direction, the hose  55   a  is automatically wound by the winder  58   a , so that loosening of the hose  55   a  is prevented. As a result, it is possible to prevent a part of the hose  55   a  from being sandwiched between the traveling rail  420  and the tank installation part  429  and from colliding with a storage shelf  1  or the frame  421  of the stacker crane  42 . 
     Instead of the discharge device  50 , the supply device  51  can be placed on the conveyance device  4 . 
     As illustrated in  FIGS.  13  and  14   , a part of the structure of the supply device  51  is the same as the structure of the discharge device  50 . The supply device  51  includes a nozzle  52   b  that supplies the cultivation liquid L 1 , more specifically, a nourishing liquid L 11 , a connector  53   b  that connects the nozzle  52   b  to a connection target, and a hose  55   b  that connects a tank  7  to be described later and the nozzle  52   b . The supply device  51  further includes an imaging device  57   b  that images the cultivation tank  3 , a controller (not illustrated) that controls the connector  53   b  and the imaging device  57   b , a winder  58   b  that automatically winds the hose  55   b , and a base  59   b . All other components of the supply device  51 , that is, the nozzle  52   b , the connector  53   b , the hose  55   b , the imaging device  57   b , the winder  58   b , and the controller are installed on the base  59   b  to form a nozzle unit. 
     The nozzle  52   b , the connector  53   b , the hose  55   b , the imaging device  57   b , the controller, the winder  58   b , and the base  59   b  of the supply device  51  have the same structure as the nozzle  52   a , the connector  53   a , the hose  55   a , the imaging device  57   a , the controller, the winder  58   a , and the base  59   a  of the discharge device  50 . 
     In the present embodiment, the supply device  51  does not include a pump. Additionally, the supply device  51  does not have a tank, more specifically, a tank to be conveyed by the conveyance device  4 . The supply device  51  may include a small pump such as a vacuum pump in a part of the hose  55   b.    
     The nozzle unit of the supply device  51  is detachably installed in the nozzle installation part  428 , that is, the lift  41 . With the fork device provided in the nozzle installation part  428 , the nozzle unit of the supply device  51  can be placed on and off the nozzle installation part  428 . 
     The cultivation equipment of Embodiment 2 further includes: a tank  7  which is installed in the storage shelf  1  and stores the cultivation liquid L 1 , more specifically, the nourishing liquid L 11 ; and a supply pipe  70  which is connected to the tank  7  and supplies a new cultivation liquid L 1  to the tank  7 . 
     The tank  7  is installed in one of the plurality of storage areas A 2  of storage shelf  1 . In the present embodiment, the tank  7  is installed in the storage area A 2  that is one end in direction D1 and is positioned in the uppermost part among the plurality of storage areas A 2  of the storage shelf  1 . 
     The hose  55   b  is detachably connected to the bottom of the tank  7 . Additionally, a downstream end of the supply pipe  70  is detachably connected to the bottom of the tank  7 . An upstream end of the supply pipe  70  is connected to a nourishing liquid tank (not illustrated) in which the new cultivation liquid L 1 , that is, the nourishing liquid L 11  is stored. A pump is provided in a part of the supply pipe  70 . 
     Additionally, the tank  7  is provided with a water level sensor (not illustrated). The pump provided in the supply pipe  70  is controlled to switch between driving and stopping according to the detection result of the water level sensor. 
     As a result, a predetermined amount of the new cultivation liquid L 1  supplied from the supply pipe  70 , that is, the nourishing liquid L 11  can be stored in the tank  7 . The cultivation liquid L 1  in the tank  7  flows to the nozzle  52   b  through the hose  55   b . As a result, the new cultivation liquid L 1  can be ejected from the nozzle  52   b.    
     The supply device  51  further includes a switching mechanism that switches between supply and supply stop of the new cultivation liquid L 1  from the nozzle  52   b . The switching mechanism is, for example, an electric valve or a pump provided in the nozzle  52   b , and is controlled by the controller. 
     In the cultivation equipment of Embodiment 2, the storage shelf  1  is provided with a standby part  13  on which the nozzle unit of the supply device  51  can be placed. In the present embodiment, the standby part  13  is an extended shelf  130  protruding outward in direction D1 from one end of the storage shelf  1  in direction D1. The standby part  13  may be a part adjacent to the part where the tank  7  is installed in a shelf member  10  of the storage shelf  1  in direction D3 or direction D1, and in this case, the nozzle unit of the supply device  51  is stored in one of storage areas A 2 . 
     By installing the supply device  51  in the standby part  13 , it is possible to keep the hose  55   b  of the supply device  51  from hindering conveyance when the cultivation unit  2  is conveyed by the conveyance device  4 . 
     The supply pipe  70  can also be used as a discharge pipe for discharging the cultivation liquid L 1  in the tank  7 . In this case, a branched branch pipe is provided in a part of the supply pipe  70 , specifically, a part closer to the tank  7  than the pump, and a valve is provided in the branch pipe. By stopping the pump and opening the valve, the cultivation liquid L 1  in the tank  7  can be discharged to the nourishing liquid tank, for example, through the supply pipe  70 . By discharging the cultivation liquid L 1  in the tank  7  through supply pipe  70 , the tank  7  can be brought into a state where the tank  7  does not contain the cultivation liquid L 1 . The tank  7  can also be moved by the conveyance device  4  by detaching the hose  55   b  and the supply pipe  70 . As a result, maintenance such as cleaning of the tank  7  can be performed in the work station A 1 . 
     2.2 Cultivation Method 
     Next, a cultivation method for cultivating the plant P 1  using the above-described cultivation equipment will be described. Hereinafter, parts different from the cultivation method using the cultivation equipment of Embodiment 1 will be described in detail. 
     In supply step S 20 , the stacker crane  42  of the conveyance device  4  moves the nozzle unit of the supply device  51  to the vicinity of the target cultivation unit  2 . Next, the cultivation liquid L 1  in the tank  7 , that is, the nourishing liquid L 11  is ejected from the nozzle  52   b , and a predetermined amount of the cultivation liquid L 1 , that is, the nourishing liquid L 11  is stored in a tray  30  of the cultivation tank  3  of the target cultivation unit  2 . When the ejection, in other words, the supply of the cultivation liquid L 1  to the target cultivation unit  2  is completed, the nozzle unit of the supply device  51  is moved from the nozzle installation part  428  of the stacker crane  42  onto the standby part  13 . 
     In discharge step S 21 , the nozzle unit of the discharge device  50  is installed in the nozzle installation part  428 , and the tank  54   a  of the discharge device  50  is installed in the tank installation part  429 . Next, in discharge step S 21 , the stacker crane  42  of the conveyance device  4  moves the nozzle unit of the discharge device  50  to the vicinity of the target cultivation unit  2 , and the nozzle  52   a  of the discharge device  50  is inserted into the through hole  311  of the planting panel  31  of the cultivation tank  3  of the target cultivation unit  2 . Next, a pump  56   b  of the discharge device  50  is driven to suck the cultivation liquid L 1  in the tray  30  of the cultivation tank  3 , that is, the waste liquid L 10  through the nozzle  52   a  to send the waste liquid L 10  to the tank  54   a.    
     When the tank  54   a  of the discharge device  50  is filled with the cultivation liquid L 1 , that is, the waste liquid L 10  in discharge step S 21 , the discharge device  50  is conveyed from the cultivation room  101  to the work room  102  by the conveyance device  4 . In the work room  102 , the cultivation liquid L 1  in the tank  54   a , that is, the waste liquid L 10  is discharged to the treatment apparatus  6 . When suction, in other words, discharge of the cultivation liquid L 1  from the target cultivation unit  2  is completed, the nozzle unit of the discharge device  50  is moved from the nozzle installation part  428 , and the tank  54   a  of the discharge device  50  is moved from the tank installation part  429 . 
     In pre-carry-out discharge step S 3 , the discharge device  50  is used to discharge the cultivation liquid L 1  to all of the plurality of cultivation tanks  3  of the target cultivation unit  2  in the same manner as discharge step S 21  described above. 
     Carry-out step S 4  is a step of carrying out the target cultivation unit  2  from which the cultivation liquid L 1  is discharged from the storage shelf  1  to the work station A 1  using the conveyance device  4 . Here, as the conveyance device  4 , a conveyance device in a state where neither the discharge device  50  nor the nozzle unit of the supply device  51  is installed in the nozzle installation part  428  and the tank  54   a  of the discharge device  50  is not installed in the tank installation part  429  is used. 
     2.3 Action and Effect 
     The cultivation equipment of the present embodiment described above includes the discharge device  50  and the supply device  51  which are movable in the cultivation room  101  and can supply and discharge the cultivation liquid L 1  to and from the plurality of cultivation tanks  3  of the plurality of cultivation units  2  in the storage shelf  1 . 
     For this reason, in the cultivation equipment of the present embodiment, there is no need to install a large number of pipes or a large pump for supply or discharge of the cultivation liquid L 1  in the storage shelf  1 , and it is possible to prevent complication and upsizing of the equipment. Accordingly, in the cultivation equipment of the present embodiment, the storage shelf  1  is easily increased in height, and the harvest amount per unit area is easily increased. 
     Additionally, in the cultivation equipment of the present embodiment, when the cultivation unit  2  is conveyed between the storage shelf  1  and the work station A 1  by the conveyance device  4 , a plurality of cultivation tanks  3  of the cultivation unit  2  can be kept in a state where the cultivation tanks  3  do not contain or substantially do not contain the cultivation liquid L 1 . 
     Hence, in the cultivation equipment of the present embodiment, the weight of the cultivation unit  2  at the time of conveyance can be curbed, and the load applied to the conveyance device  4  can be curbed. Additionally, in the cultivation equipment of the present embodiment, there is no risk of liquid leakage from the cultivation unit  2  at the time of conveyance. Hence, the conveyance speed of the cultivation unit  2  can be increased, and the harvest amount per unit time can be improved. 
     Additionally, in the cultivation equipment of the present embodiment, since the discharge device  50  and the supply device  51  can be moved by the conveyance device  4  which conveys the cultivation unit  2 , a separate conveyance device is not required, and equipment cost can be kept low. 
     Additionally, in the cultivation equipment of the present embodiment, the heavy tank  54   a  in the discharge device  50  only moves horizontally and does not move vertically, so that it is possible to curb the load applied to a lift device (not illustrated) of the stacker crane  42  at the time of conveyance. 
     Additionally, in the cultivation equipment of the present embodiment, since only a relatively light part of the discharge device  50  other than the tank  54   a , that is, only the nozzle unit is lifted and lowered, the lifting and lowering speed of the nozzle unit can be easily improved, and the work efficiency of discharging the cultivation liquid L 1  can be enhanced. 
     Additionally, in the cultivation equipment of the present embodiment, the heavy tank  7  is installed on the storage shelf  1  and does not move, so that it is possible to curb the load applied to the traveling device  426  and the lift device (not illustrated) of the stacker crane  42  at the time of conveyance. 
     Additionally, in the cultivation equipment of the present embodiment, only the nozzle unit of the supply device  51  which is lighter than the tank  7  is lifted and lowered, so that the lifting and lowering speed of the nozzle unit can be easily improved, and the work efficiency of supplying the cultivation liquid L 1  can be enhanced. 
     Additionally, in the cultivation equipment of the present embodiment, since the new cultivation liquid L 1 , that is, the nourishing liquid L 11  can be automatically supplied from the supply pipe  70  into the tank  7 , movement of the tank  7  by the conveyance device  4  is unnecessary, and the conveyance efficiency can be improved accordingly. 
     Additionally, in the cultivation equipment of the present embodiment, since the tank  7  is disposed in the storage area A 2  at the uppermost part of the storage shelf  1 , the weight of the new cultivation liquid L 1 , that is, the nourishing liquid L 11  stored in the tank  7  can be used when the new cultivation liquid L 1  is sent from the tank  7  to the nozzle  52   b , and the pump can be omitted or downsized. 
     2.4 Modification 
     The cultivation equipment of Embodiment 2 described above can adopt the following modifications. 
     The cultivation equipment of Embodiment 2 can adopt modifications similar to the cultivation equipment of Embodiment 1 described above. 
     Additionally, the discharge device  50  illustrated in  FIG.  12    may further have a function of supplying a new cultivation liquid L 1 , that is, the nourishing liquid L 11 , similarly to the discharge/supply device  5  of Embodiment 1. Additionally, the supply device  51  and the tank  7  illustrated in  FIGS.  13  and  14    may further have a function of discharging the cultivation liquid L 1 , that is, the waste liquid L 10 , similarly to the discharge/supply device  5  of Embodiment 1. In these cases, the cultivation equipment of Embodiment 2 only needs to include one of the discharge device  50  or the supply device  51  and tank  7 . 
     3. SUMMARY 
     As in the cultivation equipment of the above-described embodiments and modifications thereof, the cultivation equipment of a first aspect has the following configuration. 
     That is, the cultivation equipment of the first aspect includes a storage shelf ( 1 ), and a plurality of cultivation tanks ( 3 ) that are stored in the storage shelf ( 1 ) and hold plants (P 1 ) and a cultivation liquid (L 1 ). The cultivation equipment of the first aspect further includes a discharge device ( 50 ) and a supply device ( 51 ). The discharge device ( 50 ) is movable among a plurality of cultivation tanks ( 3 ), and discharges the cultivation liquid (L 1 ) from each of the plurality of cultivation tanks ( 3 ). The supply device ( 51 ) is movable among the plurality of cultivation tanks ( 3 ), and supplies the cultivation liquid (L 1 ) to each of the plurality of cultivation tanks ( 3 ). 
     In the cultivation equipment of the first aspect having the above-mentioned configuration, with respect to each of the cultivation tanks ( 3 ) stored in the storage shelf ( 1 ), the cultivation liquid (L 1 ) in each of the cultivation tanks ( 3 ) can be discharged by the discharge device ( 50 ), and the cultivation liquid (L 1 ) can be supplied to each of the cultivation tanks ( 3 ) by the supply device ( 51 ). Hence, in the cultivation equipment of the first aspect, there is no need to install a large number of pipes or a large pump for supplying or discharging the cultivation liquid (L 1 ) in the storage shelf ( 1 ). Hence, it is possible to prevent complication and upsizing of the equipment, so that the storage shelf ( 1 ) is easily increased in height, and the harvest amount per unit area is easily increased. Additionally, in the cultivation equipment of the first aspect, when the plurality of cultivation tanks ( 3 ) are conveyed between the work station (A 1 ) for performing various works and the storage shelf ( 1 ), the plurality of cultivation tanks ( 3 ) can be kept in a state where the cultivation tanks ( 3 ) do not contain or substantially do not contain the cultivation liquid (L 1 ). Hence, in the cultivation equipment of the first aspect, the weight of each cultivation tank ( 3 ) at the time of conveyance can be reduced, the load of conveyance can be reduced, and also liquid leakage from each cultivation tank ( 3 ) at the time of conveyance can be prevented. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a second aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the first aspect. 
     That is, the cultivation equipment of the second aspect further includes: a plurality of cultivation units ( 2 ) that are stored in the storage shelf ( 1 ) and in which a plurality of cultivation tanks ( 3 ) are installed; and a conveyance device ( 4 ) that conveys at least one cultivation unit ( 2 ) of the plurality of cultivation units ( 2 ) between the storage shelf ( 1 ) and a work station (A 1 ) separated from the storage shelf ( 1 ). The discharge device ( 50 ) and the supply device ( 51 ) are conveyed by the conveyance device ( 4 ). 
     In the cultivation equipment of the second aspect having the above-mentioned configuration, since the discharge device ( 50 ) and the supply device ( 51 ) can be conveyed by the conveyance device ( 4 ) that conveys the cultivation unit ( 2 ), a separate conveyance device is not required and equipment cost can be kept low. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a third aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the second aspect. 
     That is, in the cultivation equipment of the third aspect, the discharge device ( 50 ) and the supply device ( 51 ) are configured by one discharge/supply device ( 5 ) that performs both discharging and supplying of the cultivation liquid (L 1 ). 
     In the cultivation equipment of the third aspect having the above-mentioned configuration, it is possible to efficiently discharge and supply the cultivation liquid (L 1 ) as compared with a case where the discharge device ( 50 ) and the supply device ( 51 ) are provided separately. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a fourth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the third aspect. 
     That is, in the cultivation equipment of the fourth aspect, the conveyance device ( 4 ) includes: a horizontally moving part ( 40 ) that moves in the horizontal direction; and a lift ( 41 ) that is integrated with the horizontally moving part ( 40 ) and moves in the vertical direction. The discharge/supply device ( 5 ) includes a nozzle ( 52 ) that discharges and supplies the cultivation liquid (L 1 ), a connector ( 53 ) that connects the nozzle ( 52 ) to a connection target, a tank ( 54 ) that stores the cultivation liquid (L 1 ), and a hose ( 55 ) that connects the tank ( 54 ) and the nozzle ( 52 ). The nozzle ( 52 ), the connector ( 53 ), and the tank ( 54 ) are installed in the lift ( 41 ). 
     In the cultivation equipment of the fourth aspect having the above-mentioned configuration, the nozzle ( 52 ), the connector ( 53 ), and the tank ( 54 ) of the discharge/supply device ( 5 ) can be moved together by the lift ( 41 ) of the conveyance device ( 4 ). Hence, the distance between the nozzle ( 52 ) and the tank ( 54 ) can be shortened. For this reason, in the cultivation equipment of the fourth aspect, a time required for moving the cultivation liquid (L 1 ) between the nozzle ( 52 ) and the tank ( 54 ) can be shortened, and the work efficiency of discharging and supplying the cultivation liquid (L 1 ) can be easily enhanced. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a fifth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the second aspect. 
     That is, in the cultivation equipment of the fifth aspect, the conveyance device ( 4 ) includes a horizontally moving part ( 40 ) that moves in the horizontal direction, and a lift ( 41 ) that is integrated with the horizontally moving part ( 40 ) and moves in the vertical direction. The discharge device ( 50 ) includes a nozzle ( 52   a ) that discharges the cultivation liquid (L 1 ), a connector ( 53   a ) that connects the nozzle ( 52   a ) to a connection target, a tank ( 54   a ) that stores the cultivation liquid (L 1 ), and a hose ( 55   a ) that connects the tank ( 54   a ) and the nozzle ( 52   a ). The nozzle ( 52   a ) and the connector ( 53   a ) are installed in the lift ( 41 ), and the tank ( 54   a ) is installed in the horizontally moving part ( 40 ). 
     In the cultivation equipment of the fifth aspect having the above-mentioned configuration, the heavy tank ( 54   a ) in the discharge device ( 50 ) only moves horizontally and does not move vertically, so that it is possible to curb the load applied to the conveyance device ( 4 ). Further, in the cultivation equipment of the fifth aspect, since the nozzle ( 52   a ) and the connector ( 53   a ) that are lighter than the tank ( 54   a ) in the discharge device ( 50 ) are lifted and lowered, the lifting and lowering speed of the nozzle ( 52   a ) and the connector ( 53   a ) can be easily improved, and the work efficiency of discharging the cultivation liquid (L 1 ) can be enhanced. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a sixth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the second or fifth aspect. 
     That is, the cultivation equipment of the sixth aspect further includes a tank ( 7 ) that is installed in the storage shelf ( 1 ) and stores the cultivation liquid (L 1 ), and a supply pipe ( 70 ) that is connected to the tank ( 7 ) and supplies the cultivation liquid (L 1 ) to the tank ( 7 ). The conveyance device ( 4 ) includes the horizontally moving part ( 40 ) that moves in the horizontal direction, and the lift ( 41 ) that is integrated with the horizontally moving part ( 40 ) and moves in the vertical direction. The supply device ( 51 ) includes a nozzle ( 52   b ) that supplies the cultivation liquid (L 1 ), a connector ( 53   b ) that connects the nozzle ( 52   b ) to a connection target, and a hose ( 55   b ) that connects the tank ( 7 ) and the nozzle ( 52   b ). The lift ( 41 ) is provided with the nozzle ( 52   b ) and the connector ( 53   b ). 
     In the cultivation equipment of the sixth aspect having the above configuration, the heavy tank ( 7 ) is installed in the storage shelf ( 1 ) and does not move, so that it is possible to curb the load applied to the conveyance device ( 4 ). Additionally, in the cultivation equipment of the sixth aspect, since the nozzle ( 52   b ) and the connector ( 53   b ) that are lighter than the tank ( 7 ) are lifted and lowered, the lifting and lowering speed of the nozzle ( 52   b ) and the connector ( 53   b ) can be easily improved, and the work efficiency of supplying the cultivation liquid (L 1 ) can be enhanced. Additionally, in the cultivation equipment of the sixth aspect, the cultivation liquid (L 1 ) can be supplied into the tank ( 7 ) through the supply pipe ( 70 ). Hence, in the cultivation equipment of the sixth aspect, movement of the tank ( 7 ) by the conveyance device ( 4 ) is unnecessary, and the conveyance efficiency can be improved accordingly. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a seventh aspect also includes the following configuration in addition to the configuration of the cultivation equipment of any one of the fourth to sixth aspects. 
     That is, the cultivation equipment of the seventh aspect further includes an imaging device ( 57 ,  57   a ,  57   b ) that is installed in the lift ( 41 ) and images the plurality of cultivation tanks ( 3 ). 
     In the cultivation equipment of the seventh aspect having the above-mentioned configuration, by imaging a plurality of cultivation tanks ( 3 ) by using the imaging device ( 57 ,  57   a ,  57   b ), the growth state of the plants (P 1 ) held in each of the cultivation tanks ( 3 ) can be checked at a place separated from the storage shelf ( 1 ), such as at the work station (A 1 ). Hence, in the cultivation equipment of the seventh aspect, the cultivation unit ( 2 ) can be prevented from being conveyed from the storage shelf ( 1 ) to the work station (A 1 ) at an inappropriate timing, and the number of times of conveyance of the cultivation unit ( 2 ) can be curbed. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of an eighth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of the sixth aspect. 
     That is, in the cultivation equipment of the eighth aspect, the storage shelf ( 1 ) further includes a standby part ( 13 ) in which the nozzle ( 52   b ) of the supply device ( 51 ) and the connector ( 53   b ) can be installed, and the lift ( 41 ) includes a moving device that moves the nozzle ( 52   b ) and the connector ( 53   b ) between the lift ( 41 ) and the standby part ( 13 ), specifically, a fork device provided in the nozzle installation part ( 428 ). 
     In the cultivation equipment of the eighth aspect including the above-mentioned configuration, when the supply device ( 51 ) is not used, the supply device ( 51 ) can be installed in the standby part ( 13 ). Hence, in the cultivation equipment of the eighth aspect, when the cultivation unit ( 2 ) is conveyed by the conveyance device ( 4 ), the hose ( 55   b ) connecting the nozzle ( 52   b ) of the supply device ( 51 ) and the tank ( 7 ) can be prevented from interfering with the conveyance of the cultivation unit ( 2 ). 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a ninth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of any one of the fourth to eighth aspects. 
     That is, the cultivation equipment of the ninth aspect further includes a treatment apparatus ( 6 ) that treats the cultivation liquid (L 1 ) discharged from a tank ( 54 ,  54   a ). The treatment apparatus ( 6 ) includes a receiving member ( 60 ) that receives the cultivation liquid (L 1 ) discharged from the tank ( 54 ,  54   a ), a contaminant separator ( 61 ) that removes contaminants in the cultivation liquid (L 1 ), a filter ( 62 ) that filters the cultivation liquid (L 1 ), a sterilizer ( 63 ) that sterilizes the filtered cultivation liquid (L 1 ) to obtain a treated liquid (L 2 ), and a treated liquid tank ( 64 ) that stores the treated liquid (L 2 ). 
     In the cultivation equipment of the ninth aspect having the above configuration, the cultivation liquid (L 1 ) collected in the tank ( 54 ,  54   a ) can be treated in a reusable manner using the treatment apparatus ( 6 ). In the cultivation equipment of the ninth aspect, the cultivation liquid (L 1 ) collected in the tank ( 54 ,  54   a ) can be regenerated every time using the treatment apparatus ( 6 ). Hence, a large treatment apparatus provided in a conventional plant factory becomes unnecessary. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of a tenth aspect also includes the following configuration in addition to the configuration of the cultivation equipment of any one of the second to ninth aspects. 
     That is, in the cultivation equipment of the tenth aspect, each of the plurality of cultivation units ( 2 ) includes: a first unit ( 25 ) having a plurality of support plates ( 20 ) on which a plurality of cultivation tanks ( 3 ) are installed; and a second unit ( 26 ) that can be combined with the first unit ( 25 ) and has an irradiation device ( 22 ) that irradiates the plurality of cultivation tanks ( 3 ) with grow light. The second unit ( 26 ) is fixed to the storage shelf ( 1 ), and the first unit ( 25 ) is conveyed by the conveyance device ( 4 ). 
     In the cultivation equipment of the tenth aspect having the above configuration, it is possible to convey only the first unit ( 25 ) in which the plurality of cultivation tanks ( 3 ) are installed among the cultivation units ( 2 ), and the second unit ( 26 ) including the irradiation device ( 22 ) can be left in the storage shelf ( 1 ). Hence, in the cultivation equipment of the tenth aspect, there is no need to provide a structure for performing wireless power transfer, for example, in the storage shelf ( 1 ) and the cultivation unit ( 2 ), and equipment cost can be kept low. 
     Additionally, as in the cultivation equipment of the above-described embodiments and modifications thereof, cultivation equipment of an 11th aspect also includes the following configuration in addition to the configuration of the cultivation equipment of any one of the fourth to ninth aspects. 
     That is, in the cultivation equipment of the 11th aspect, each of the plurality of cultivation units ( 2 ) includes: a unit tank ( 27 ) that stores the cultivation liquid (L 1 ); a supply pipe ( 28 ) that connects the unit tank ( 27 ) and the plurality of cultivation tanks ( 3 ) and supplies the cultivation liquid (L 1 ) in the unit tank ( 27 ) to the plurality of cultivation tanks ( 3 ); and a discharge pipe ( 29 ) that connects the unit tank ( 27 ) and the plurality of cultivation tanks ( 3 ) and discharges the cultivation liquid (L 1 ) in the plurality of cultivation tanks ( 3 ) to the unit tank ( 27 ). The connection target of the connector ( 53 ,  53   a ,  53   b ) is the unit tank ( 27 ). 
     In the cultivation equipment of the 11th aspect having the above-mentioned configuration, when the nozzle ( 52 ,  52   a ,  52   b ) is connected to the unit tank ( 27 ) by the connector ( 53 ,  53   a ,  53   b ), the cultivation liquid (L 1 ) can be discharged, supplied, or both to and from the plurality of cultivation tanks ( 3 ). Hence, in the cultivation equipment of the 11th aspect, as compared with a case where the nozzle ( 52 ,  52   a ,  52   b ) is sequentially connected to the plurality of cultivation tanks ( 3 ) by the connector ( 53 ,  53   a ,  53   b ) to discharge or supply the cultivation liquid (L 1 ), or both, the work efficiency of discharging or supplying the cultivation liquid (L 1 ) can be enhanced. 
     Additionally, as in the cultivation method of the above-described embodiments and modifications thereof, a cultivation method of a 12th aspect has the following configuration. 
     That is, the cultivation method of the 12th aspect includes carry-in step (S 1 ), supply step (S 20 ), and discharge step (S 21 ). In cultivation step (S 2 ), a plurality of cultivation tanks ( 3 ) that hold plants (P 1 ) and a cultivation liquid (L 1 ) are stored in a storage shelf ( 1 ). In supply step (S 20 ), the cultivation liquid (L 1 ) is supplied to the plurality of cultivation tanks ( 3 ) by a supply device ( 51 ) movable among the plurality of cultivation tanks ( 3 ). In discharge step (S 21 ), the cultivation liquid (L 1 ) in the plurality of cultivation tanks ( 3 ) is discharged by a discharge device ( 50 ) movable among the plurality of cultivation tanks ( 3 ). 
     In the cultivation method of the 12th aspect having the above-mentioned configuration, with respect to each of the cultivation tanks ( 3 ) stored in the storage shelf ( 1 ), the cultivation liquid (L 1 ) in each of the cultivation tanks ( 3 ) can be discharged by the discharge device ( 50 ), and the cultivation liquid (L 1 ) can be supplied to each of the cultivation tanks ( 3 ) by supply device ( 51 ). Hence, in the cultivation method of the 12th aspect, there is no need to install a large number of pipes or a large pump for supplying or discharging the cultivation liquid (L 1 ) in the storage shelf ( 1 ). Hence, it is possible to prevent complication and upsizing of the equipment, so that the storage shelf ( 1 ) is easily increased in height, and the harvest amount per unit area is easily increased. Additionally, in the cultivation method of the 12th aspect, when the plurality of cultivation tanks ( 3 ) are conveyed between the work station (A 1 ) for performing various works and the storage shelf ( 1 ), the plurality of cultivation tanks ( 3 ) can be kept in a state where the cultivation tanks ( 3 ) do not contain or substantially do not contain the cultivation liquid (L 1 ). Hence, in the cultivation method of the 12th aspect, the weight of the plurality of cultivation tanks ( 3 ) at the time of conveyance can be reduced, the load of conveyance can be reduced, and also liquid leakage from each cultivation tank ( 3 ) at the time of conveyance can be prevented. 
     Additionally, as in the cultivation method of the above-described embodiments and modifications thereof, a cultivation method of a 13th aspect also includes the following configuration in addition to the configuration of the cultivation method of the 12th aspect. 
     That is, in the cultivation method of the 13th aspect, movement of the discharge device ( 50 ) and the supply device ( 51 ) among the plurality of cultivation tanks ( 3 ) is performed by the conveyance device ( 4 ) that conveys the plurality of cultivation tanks ( 3 ) between the storage shelf ( 1 ) and the work station (A 1 ) separated from the storage shelf ( 1 ). 
     In the cultivation method of the 13th aspect having the above-mentioned configuration, since the discharge device ( 50 ) and the supply device ( 51 ) can be moved by the conveyance device ( 4 ), a separate dedicated conveyance device is not required, and the equipment cost can be kept low. 
     While the present disclosure has been described above on the basis of the embodiments illustrated in the accompanying drawings, the present disclosure is not limited to the above embodiments, and appropriate design changes can be made within the intended scope of the present disclosure. 
     LIST OF REFERENCE NUMERALS 
     
         
         
           
               1  storage shelf 
               2  cultivation unit 
               20  support plate 
               22  irradiation device 
               25  first unit 
               26  second unit 
               27  unit tank 
               28  supply pipe 
               29  discharge pipe 
               3  cultivation tank 
               4  conveyance device 
               5  discharge/supply device 
               50  discharge device 
               51  supply device 
               52 ,  52   a ,  52   b  nozzle 
               53 ,  53   a ,  53   b  connector 
               54 ,  54   a  tank 
               55 ,  55   a ,  55   b  hose 
               57 ,  57   a ,  57   b  imaging device 
               6  treatment apparatus 
               60  receiving member 
               61  contaminant separator 
               62  filter 
               63  sterilizer 
               64  treated liquid tank 
               7  tank 
               70  supply pipe 
             A 1  work station 
             P 1  plant 
             L 1  cultivation liquid 
             L 2  treated liquid 
             S 1  carry-in step 
             S 20  supply step 
             S 21  discharge step