Air composition adjusting device, refrigerator, and storage chamber

Abstract

To adjust the composition of in-chamber air appropriately.SOLUTION: An air composition adjusting device (90) includes a composition adjusting part (100), an air supply part (40) and a controller (110). The composition adjusting part (100) supplies gas to be treated whose composition is different from that of air outside the chamber to a storage chamber (2). The air supply part (40) supplies the air outside the chamber to the storage chamber (2). The controller (110) performs a two-operation mode. In the two-operation mode, the controller (110) causes the air supply part (40) to supply the air outside the chamber to the storage chamber (2), and causes the composition adjusting part (100) to supply the gas to be treated to the storage chamber (2).SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present disclosure relates to air composition conditioning devices, refrigeration devices, and storage units. [Background technology]

[0002] Patent Document 1 discloses an internal air conditioning device that adjusts the composition of the internal air in a transport container. The internal air conditioning device adjusts the oxygen concentration and carbon dioxide concentration of the internal air in order to maintain the freshness of fruits and vegetables housed in a transport container that serves as a storage facility. The internal air conditioning device processes external air to generate a treated gas having a different composition from the external air, and supplies the treated gas to the internal space. The internal air conditioning device also performs an operation of supplying external air to the internal space. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-148877 A Summary of the Invention [Problem to be solved by the invention]

[0004] The respiration rate of fruits and vegetables stored in a storage facility varies depending on the type and condition of the fruits and vegetables. For example, when the respiration rate of fruits and vegetables is high, the amount of carbon dioxide generated by the respiration of the fruits and vegetables is also high. Therefore, the carbon dioxide concentration of the air inside the storage facility cannot be reduced to the target value by the operation of the air conditioning device inside the storage facility, and there is a risk that the composition of the air inside the storage facility cannot be adjusted to a composition suitable for maintaining the freshness of the fruits and vegetables.

[0005] An object of the present disclosure is to appropriately adjust the composition of the air inside the cabinet. [Means for solving the problem]

[0006] A first aspect of the present disclosure is an air composition adjustment device (90) that adjusts the composition of internal air inside a storage cabinet (2), and includes a composition adjustment unit (100) that generates a gas to be treated having a composition different from that of the external air by treating external air and supplies the gas to be treated to the storage cabinet (2), an air supply unit (40) that supplies the external air to the storage cabinet (2), and a controller (110) that controls the composition adjustment unit (100) and the air supply unit (40), and the controller (110) performs a dual operation mode of causing the air supply unit (40) to supply the external air to the storage cabinet (2) and causing the composition adjustment unit (100) to supply the gas to be treated to the storage cabinet (2).

[0007] In the first embodiment, the controller (110) operates in a dual operation mode. The dual operation mode is a control mode in which the air supply unit (40) supplies outside air to the storage (2) and the composition adjustment unit (100) supplies the gas to be treated to the storage (2). The carbon dioxide concentration of the outside air is substantially the same as the carbon dioxide concentration of the atmosphere, and is very low. The carbon dioxide concentration of the gas to be treated generated by treating the outside air is also very low, similar to the carbon dioxide concentration of the outside air. Therefore, by the air supply unit (40) supplying outside air to the storage (2) and the composition adjustment unit (100) supplying the gas to be treated to the storage (2), the carbon dioxide concentration of the air inside the storage (2) is reduced compared to when one of the air supply unit (40) and the composition adjustment unit (100) is operating and the other is not operating. As a result, even when the respiration rate of fruits and vegetables stored in the storage (2) is high, the composition of the air inside the storage (2) can be appropriately adjusted.

[0008] In a second aspect of the present disclosure, in the first aspect, the treated gas generated by the composition adjustment unit (100) contains a low oxygen concentration gas having a lower oxygen concentration than the outside air, and in the dual operation mode, the controller (110) causes the composition adjustment unit (100) to supply the low oxygen concentration gas to the storage facility (2).

[0009] In the second embodiment, the controller (110) in the dual operation mode causes the composition adjustment unit (100) to supply a low oxygen concentration gas to the storage container (2). Therefore, the amount of oxygen introduced into the storage container (2) is reduced when the controller (110) is executing the dual operation mode, compared to when both the composition adjustment unit (100) and the air supply unit (40) supply outside air to the storage container.

[0010] A third aspect of the present disclosure is the first or second aspect, further comprising a detector (160) for detecting a concentration of one or more components of the inside air, and the controller (110) operates in a single operation mode in which the operation of the composition adjustment unit (100) is controlled based on a value detected by the detector (160) while the supply of the outside air to the storage unit (2) by the air supply unit (40) is stopped, and switches between the single operation mode and the dual operation mode based on the detection value of the detector (160).

[0011] In the third embodiment, the controller (110) switches the control mode to be executed from one of the single operation mode and the dual operation mode to the other, based on the detection value of the detector (160). Therefore, the composition of the air inside the refrigerator can be more appropriately adjusted than when only one of the single operation mode and the dual operation mode is used.

[0012] A fourth aspect of the present disclosure is the third aspect, wherein the detector (160) includes an oxygen sensor (161) that detects an oxygen concentration in the interior air and a carbon dioxide sensor (162) that detects a carbon dioxide concentration in the interior air, and the controller (110) terminates the one-operation mode and executes the dual operation mode when, during execution of the one-operation mode, the detection value of the oxygen sensor (161) is lower than a first predetermined value and the detection value of the carbon dioxide sensor (162) is higher than a second predetermined value.

[0013] In the fourth aspect, when the detection value of the oxygen sensor (161) is lower than a first predetermined value and the detection value of the carbon dioxide sensor (162) is higher than a second predetermined value, the controller (110) switches the control mode to be executed from the single operation mode to the dual operation mode. This makes it possible to more appropriately adjust the composition of the air inside the refrigerator than when only one of the single operation mode and the dual operation mode is used.

[0014] A fifth aspect of the present disclosure is the fourth aspect, wherein the air supply unit (40) is capable of changing the flow rate of the outside air supplied to the storage compartment (2), and the controller (110) increases the flow rate of the outside air supplied to the storage compartment (2) by the air supply unit (40) when the detection value of the oxygen sensor (161) decreases while the dual operation mode is being executed.

[0015] When the detection value of the oxygen sensor (161) decreases while the controller (110) is executing the dual operation mode, it is assumed that the amount of oxygen supplied to the storage (2) is smaller than the amount of oxygen consumed by the respiration of the fruits and vegetables in the storage (2). Therefore, when the detection value of the oxygen sensor (161) decreases while the controller (110) of the fifth aspect is executing the dual operation mode, the controller (110) increases the flow rate of outside air supplied to the storage (2) by the air supply unit (40). As a result, the decrease in the oxygen concentration of the inside air is suppressed.

[0016] A sixth aspect of the present disclosure is the fourth aspect, wherein the air supply unit (40) is capable of changing the flow rate of the outside air supplied to the storage compartment (2), and the controller (110) reduces the flow rate of the outside air supplied to the storage compartment (2) by the air supply unit (40) when the rate of increase of the detection value of the oxygen sensor (161) is higher than a third predetermined value while the dual operation mode is being executed.

[0017] When the controller (110) is executing the dual operation mode, if the rate of increase in the detection value of the oxygen sensor (161) is high, it is presumed that the amount of oxygen supplied to the storage (2) is greater than the amount of oxygen consumed by the respiration of the fruits and vegetables in the storage (2). Therefore, when the rate of increase in the detection value of the oxygen sensor (161) is high while the controller (110) of the sixth aspect is executing the dual operation mode, the controller (110) reduces the flow rate of outside air supplied to the storage (2) by the air supply unit (40). As a result, an increase in the oxygen concentration of the inside air is suppressed.

[0018] A seventh aspect of the present disclosure is that in any one of the fourth to sixth aspects, when the detection value of the oxygen sensor (161) is higher than a fourth predetermined value or the detection value of the carbon dioxide sensor (162) is lower than a fifth predetermined value during execution of the dual operation mode, the controller (110) terminates the dual operation mode and executes the single operation mode, wherein the fourth predetermined value is higher than the first predetermined value and the fifth predetermined value is lower than the second predetermined value.

[0019] In the seventh aspect, when the detection value of the oxygen sensor (161) is higher than a fourth predetermined value or when the detection value of the carbon dioxide sensor (162) is lower than a fifth predetermined value, the controller (110) switches the control mode to be executed from the dual operation mode to the single operation mode.

[0020] An eighth aspect of the present disclosure is the fifth or sixth aspect, wherein the air supply unit (40) includes an air inlet (41a) having a variable opening that connects the outside of the storage cabinet (2) with the inside of the storage cabinet (2), and the controller (110) increases the flow rate of the outside air supplied to the storage cabinet (2) by the air supply unit (40) by increasing the opening of the air inlet (41a) and decreases the flow rate of the outside air supplied to the storage cabinet (2) by the air supply unit (40) by decreasing the opening of the air inlet (41a).

[0021] The controller (110) of the eighth embodiment changes the flow rate of the outside air supplied to the storage (2) by the air supply part (40) by changing the opening degree of the air inlet (41a).

[0022] A ninth aspect of the present disclosure is the fifth or sixth aspect, wherein the air supply unit (40) includes an internal fan (35) for circulating internal air inside the storage cabinet (2) and an air inlet (41a) for communicating between the outside of the storage cabinet (2) and an intake side area of ​​the internal fan (35) inside the storage cabinet (2), and the controller (110) increases the flow rate of the outside air supplied by the air supply unit (40) to the storage cabinet (2) by increasing the rotation speed of the internal fan (35) and reduces the flow rate of the outside air supplied by the air supply unit (40) to the storage cabinet (2) by decreasing the rotation speed of the internal fan (35).

[0023] When the rotation speed of the internal fan (35) changes, the pressure in the suction side area of ​​the internal fan (35) inside the storage cabinet (2) changes, and the flow rate of outside air flowing from the outside to the inside of the storage cabinet (2) through the air inlet (41a) changes. Therefore, the controller (110) of the ninth aspect changes the flow rate of outside air supplied to the storage cabinet (2) by the air supply unit (40) by changing the rotation speed of the internal fan (35).

[0024] A tenth aspect of the present disclosure is any one of the third to ninth aspects, wherein the composition adjustment unit (100) is capable of performing an adjustment operation of supplying the gas to be treated to the storage tank (2) and an air introduction operation of supplying the outside air to the storage tank (2), and the controller (110) switches, in the one-way operation mode, between a state in which the composition adjustment unit (100) performs the adjustment operation, a state in which the composition adjustment unit (100) performs the air introduction operation, and a state in which the composition adjustment unit (100) pauses without performing the adjustment operation and the air introduction operation, based on a value detected by the detector (160).

[0025] The controller (110) of the tenth embodiment switches the composition adjustment unit (100) between a state in which a gas supply operation is performed, a state in which an air introduction operation is performed, and a state in which the composition adjustment unit (100) is paused without performing the gas supply operation or the air introduction operation, based on a value detected by the detector (160).

[0026] An eleventh aspect of the present disclosure is the third aspect, wherein the detector (160) includes an oxygen sensor (161) that detects an oxygen concentration of the inside air, and the controller (110) is capable of executing an oxygen concentration reduction mode in which, with the supply of the outside air to the storage cabinet (2) by the air supply unit (40) stopped, the operation of the composition adjustment unit (100) is controlled so that the detection value of the oxygen sensor (161) decreases from the oxygen concentration of the outside air to a sixth predetermined value, and a composition maintenance mode in which, after the oxygen concentration reduction mode is terminated, the operation of the composition adjustment unit (100) and the air supply unit (40) is controlled to maintain the composition of the inside air, and the both operation modes are performed while the composition maintenance mode is being executed.

[0027] In an eleventh embodiment, the controller (110) sequentially executes an oxygen concentration reduction mode and a composition maintenance mode. The controller (110) also executes a dual operation mode while executing the composition maintenance mode. In the dual operation mode, the controller (110) causes the air supply unit (40) to supply outside air to the storage chamber (2) and causes the composition adjustment unit (100) to supply the gas to be treated to the storage chamber (2).

[0028] A twelfth aspect of the present disclosure is related to the first aspect, in which the gas to be treated includes a first gas having a higher nitrogen concentration and a lower oxygen concentration than the outside air, and a second gas having a lower nitrogen concentration and a higher oxygen concentration than the outside air, and the composition adjustment unit (100) includes an air treatment unit (95) that separates the outside air into the first gas and the second gas.

[0029] In the twelfth aspect, the air treatment section (95) of the composition adjustment section (100) separates the outside air into a first gas and a second gas.

[0030] A thirteenth aspect of the present disclosure is the twelfth aspect, wherein the air treatment unit (95) of the composition adjustment unit (100) includes an adsorbent that adsorbs nitrogen, and the composition adjustment unit (100) performs an operation of generating the second gas by adsorbing nitrogen contained in the outside air to the adsorbent of the air treatment unit (95), and an operation of generating the first gas by desorbing nitrogen from the adsorbent of the air treatment unit (95).

[0031] In a thirteenth aspect, the air treatment unit (95) of the composition adjustment unit (100) separates the outside air into a first gas and a second gas by using an adsorbent that adsorbs nitrogen.

[0032] A fourteenth aspect of the present disclosure is a refrigeration system (10) including an air composition adjustment device (90) according to any one of the first to thirteenth aspects, and a refrigerant circuit (11) that performs a refrigeration cycle to adjust the temperature of the inside air.

[0033] The refrigeration system (10) of the fourteenth aspect adjusts the composition of the inside air by the operation of the air composition adjustment device (90), and adjusts the temperature of the inside air by the operation of the refrigerant circuit (11).

[0034] A fifteenth aspect of the present disclosure is a storage unit (2) including the refrigeration apparatus (10) of the fourteenth aspect.

[0035] A storage facility (2) according to a fifteenth embodiment includes a refrigeration system (10) having an air composition regulator (90) and a refrigerant circuit (11). [Brief description of the drawings]

[0036] [Figure 1] FIG. 1 is a schematic perspective view of a transport refrigeration system according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of a transport container equipped with a transport refrigeration unit according to an embodiment. [Diagram 3] FIG. 3 is a piping diagram showing a refrigerant circuit of the transport refrigeration system of the embodiment. [Figure 4]Fig. 4 is a schematic front view of the ventilation device, Fig. 4(A) shows the cover in the closed position, Fig. 4(B) shows the cover in the intermediate position, and Fig. 4(C) shows the cover in the fully open position. [Diagram 5] FIG. 5 is a piping diagram showing the configuration of an internal air conditioning device according to an embodiment. [Figure 6] FIG. 6 is a view corresponding to FIG. 5, showing an internal air conditioning apparatus performing a first gas supplying operation. [Figure 7] FIG. 7 is a view corresponding to FIG. 5, showing an internal air conditioning apparatus performing the second gas supplying operation. [Figure 8] FIG. 8 is a view equivalent to FIG. 5, showing an internal air conditioner performing an air introduction operation. [Figure 9] FIG. 9 is a block diagram showing the configuration of a controller provided in the air composition adjustment device of the embodiment. [Figure 10] FIG. 10 is a flow diagram illustrating the operations performed by the controller of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the following description, the terms "front", "rear", "upper", "lower", "right" and "left" are based on the directions indicated by the arrows in FIG.

[0038] The present disclosure relates to a transport container 1. The transport container 1 is a reefer container capable of controlling the temperature inside. The transport container 1 is used to transport perishable goods (e.g., fruits, vegetables, flowers, etc.) that respire by absorbing oxygen (O2) from the air and releasing carbon dioxide (CO2).

[0039] As shown in Figures 1 and 2, the transport container (1) includes a container body (2) and a transport refrigeration unit (10). The transport refrigeration unit (10) is attached to the container body (2). The transport container (1) is used for marine transportation. The transport container (1) is transported by a marine transport vehicle such as a ship.

[0040] -Container body- The container body (2) is a storage facility for storing the perishable goods described above.

[0041] The container body (2) is formed in a hollow box shape. The container body (2) is formed long horizontally. An opening is formed at one end in the longitudinal direction of the container body (2). The opening of the container body (2) is closed by a transport refrigeration unit (10). A storage space (5) for storing cargo, which is perishable goods, is formed inside the container body (2).

[0042] A floor plate (3) on which cargo is placed is disposed at the bottom of the storage space (5). An underfloor flow passage (4) for flowing air blown out by the transport refrigeration unit (10) is formed between the floor plate (3) and the bottom plate of the container body (2). The underfloor flow passage (4) is a flow passage that extends in the longitudinal direction of the container body (2) along the bottom plate of the container body (2). One end of the underfloor flow passage (4) is connected to the air outlet (27) of the transport refrigeration unit (10) and the other end is connected to the space above the floor plate (3) (i.e., the space in which cargo is stored).

[0043] -Transportation refrigeration equipment- The transport refrigeration unit (10) includes a casing (20), a refrigerant circuit (11) performing a refrigeration cycle, an external fan (34), and an internal fan (35).

[0044] <Casing> The casing (20) includes an exterior wall portion (21), an interior wall portion (22), a back plate (24), and a partition plate (25). As described below, the casing (20) is provided with a refrigerant circuit (11), an exterior fan (34), and an interior fan (35).

[0045] The exterior wall portion (21) is a plate-like member arranged to cover the open end of the container body (2). A lower portion of the exterior wall portion (21) bulges inwardly from the container body (2). The interior wall portion (22) is a plate-like member shaped to fit the exterior wall portion (21). The interior wall portion (22) is arranged to cover the inner surface of the container body (2) at the exterior wall portion (21). A thermal insulating material (23) is filled in the space between the exterior wall portion (21) and the interior wall portion (22).

[0046] The lower portion of the casing (20) is recessed toward the inside of the container body (2). The lower portion of the casing (20) forms an external equipment room (28) that communicates with the external space of the transport container (1). An external fan (34) is disposed in the external equipment room (28).

[0047] The back plate (24) is a generally rectangular flat member. The back plate (24) is disposed inside the container body (2) relative to the interior wall portion (22) and forms an interior air flow path (29) between the back plate (24) and the interior wall portion (22). The interior air flow path (29) has an upper end that forms the suction port (26) of the casing (20) and a lower end that forms the air outlet (27) of the casing (20).

[0048] The partition plate (25) is a plate-like member arranged to divide the interior air flow path (29) into upper and lower parts. The partition plate (25) is arranged at the top of the interior air flow path (29). The partition plate (25) divides the interior air flow path (29) into a primary flow path (29a) above the partition plate (25) and a secondary flow path (29b) below the partition plate (25). The primary flow path (29a) communicates with the storage space (5) via the suction port (26). The secondary flow path (29b) communicates with the underfloor flow path (4) via the air outlet (27). An interior fan (35) is attached to the partition plate (25). The interior fan (35) is arranged to blow air sucked from the primary flow path (29a) into the secondary flow path (29b).

[0049] <Refrigerant circuit> As shown in Fig. 3, the refrigerant circuit (11) is a closed circuit formed by connecting a compressor (12), an external heat exchanger (13), an expansion valve (14), and an internal heat exchanger (15) with piping. When the compressor (12) is operated, a refrigerant circulates through the refrigerant circuit (11) to perform a vapor compression refrigeration cycle. As shown in Fig. 2, the external heat exchanger (13) is disposed in the external equipment room (28), and the internal heat exchanger (15) is disposed in the secondary flow path (29b) of the internal air flow path (29). The compressor (12) is also disposed in the external equipment room (28).

[0050] -Operation of transport refrigeration equipment- The transport refrigeration unit (10) performs a cooling operation to cool the air inside the transport container (1).

[0051] In the cooling operation, the compressor (12) of the refrigerant circuit (11) operates to perform a vapor compression refrigeration cycle by circulating the refrigerant in the refrigerant circuit (11). In the refrigerant circuit (11), the refrigerant discharged from the compressor (12) passes through the external heat exchanger (13), the expansion valve (14), and the internal heat exchanger (15) in that order, and is then drawn into the compressor (12) and compressed.

[0052] In addition, in the cooling operation, the external fan (34) and the internal fan (35) are operated. When the external fan (34) is operated, the external air outside the transport container (1) is sucked into the external equipment room (28) and passes through the external heat exchanger (13). In the external heat exchanger (13), the refrigerant dissipates heat to the external air and condenses. When the internal fan (35) is operated, the internal air in the storage space (5) of the transport container (1) is sucked into the internal air flow path (29) and passes through the internal heat exchanger (15). In the internal heat exchanger (15), the refrigerant absorbs heat from the internal air and evaporates.

[0053] The flow of the interior air will now be described. The interior air present in the storage space (5) flows through the intake port (26) into the primary flow path (29a) of the interior air flow path (29) and is then blown out into the secondary flow path (29b) by the interior fan (35). The interior air that has flowed into the secondary flow path (29b) is cooled as it passes through the interior heat exchanger (15), and is then blown out through the outlet port (27) into the underfloor flow path (4) and flows through the underfloor flow path (4) into the storage space (5).

[0054] In the internal air flow path (29), the primary flow path (29a) is located on the suction side of the internal fan (35), and the secondary flow path (29b) is located on the outlet side of the internal fan (35). Therefore, while the internal fan (35) is in operation, the air pressure in the secondary flow path (29b) is slightly higher than the air pressure in the primary flow path (29a).

[0055] -Air composition adjustment device- The transport refrigeration unit (10) includes an air composition adjustment unit (90). The air composition adjustment unit (90) also includes a ventilation unit (40), an interior air conditioner (100), and a controller (110).

[0056] The ventilation device (40) is an air supply unit that supplies atmospheric air, which is outside air, to the storage space (5) of the storage (2). The ventilation device (40) is capable of changing the flow rate of the outside air supplied to the storage space (5).

[0057] The internal air conditioner (100) generates a gas to be treated having a composition different from that of the external air by treating the atmospheric air, which is the external air. The internal air conditioner (100) is a composition adjustment unit that supplies the generated gas to be treated to a storage space (5) of a storage cabinet (2).

[0058] -Ventilation equipment- The ventilation device (40) will be described. The ventilation device (40) ventilates the storage space (5) of the container body (2). The ventilation device (40) has an air supply function of supplying outside air to the storage space (5) and an exhaust function of discharging inside air to the outside space (6).

[0059] <Configuration of ventilation system> As shown in Fig. 1, the ventilation device (40) is disposed in the upper left portion of the casing (20) of the transport refrigeration unit (10). As shown in Fig. 2, the ventilation device (40) is provided in a ventilation mounting opening (38) formed in the casing (20). The ventilation mounting opening (38) penetrates the casing (20) in the front-rear direction.

[0060] 2, an air supply passageway (41) and an exhaust passageway (42) are formed inside the ventilation device (40). The air supply passageway (41) and the exhaust passageway (42) connect the storage space (5) and the external space (6).

[0061] Specifically, the supply air passage (41) connects the primary flow path (29a) of the internal air flow path (29) with the external space (6). The end of the supply air passage (41) on the external space (6) side is the supply air communication port (41a). The supply air communication port (41a) is an air inlet port that connects the external space (6) with the inside of the container body (2). The exhaust air passage (42) connects the secondary flow path (29b) of the internal air flow path (29) with the external space (6). The end of the exhaust air passage (42) on the external space (6) side is the exhaust air communication port (42a). The supply air communication port (41a) and the exhaust air communication port (42a) are slightly elongated openings extending in the circumferential direction.

[0062] The ventilation device (40) includes an opening / closing lid (45). The opening / closing lid (45) is a disk-shaped member. The opening / closing lid (45) is provided so as to cover the air supply communication port (41 a) and the air exhaust communication port (42 a). The opening / closing lid (45) is driven by a motor (not shown) and is rotatable about its central axis.

[0063] As shown in Fig. 4, the open-close lid (45) is formed with an air intake opening (46) and an exhaust opening (47). The air intake opening (46) and the exhaust opening (47) each penetrate the open-close lid (45) in the thickness direction. The shape of the air intake opening (46) is the same as the shape of the air intake communication port (41a). The shape of the exhaust opening (47) is the same as the shape of the exhaust communication port (42a). The air intake opening (46) and the exhaust opening (47) are formed in the open-close lid (45) at positions such that when the air intake opening (46) entirely overlaps with the air intake communication port (41a), the exhaust opening (47) entirely overlaps with the exhaust communication port (42a).

[0064] <Ventilation system operation> The ventilation device (40) is configured to be able to adjust the flow rate of outside air supplied to the storage space (5) (intake air flow rate) and the flow rate of inside air exhausted from the storage space (5) (exhaust air flow rate) by rotating the opening / closing lid (45).

[0065] Specifically, when the opening / closing cover (45) is rotated, the area of ​​the portion of the supply air communication port (41a) that overlaps with the supply air opening (46) and the area of ​​the portion of the exhaust air communication port (42a) that overlaps with the exhaust opening (47) change. The outside air flows into the supply air passage (41) through the portion of the supply air communication port (41a) that overlaps with the supply air opening (46) and then flows into the storage space (5). The inside air flowing through the exhaust air passage (42) flows out into the outside space (6) through the portion of the exhaust air communication port (42a) that overlaps with the exhaust opening (47).

[0066] Therefore, increasing the area of ​​the portion of the intake communication port (41a) that overlaps with the intake opening (46) increases the intake air flow rate, whereas decreasing the area of ​​that portion decreases the intake air flow rate. Moreover, increasing the area of ​​the portion of the exhaust communication port (42a) that overlaps with the exhaust opening (47) increases the exhaust air flow rate, whereas decreasing the area of ​​that portion decreases the exhaust air flow rate.

[0067] When the open-close lid (45) is in the position shown in Fig. 4(A), the entire air supply communication port (41a) is covered by the open-close lid (45), and the entire air exhaust communication port (42a) is covered by the open-close lid (45). Therefore, the area of ​​the portion of the air supply communication port (41a) that overlaps with the air supply opening (46) and the area of ​​the portion of the air exhaust communication port (42a) that overlaps with the air exhaust opening (47) are both zero. In other words, the air supply passage (41) and the air exhaust passage (42) are fully closed. Therefore, in this state, the air supply flow rate and the air exhaust flow rate are both zero.

[0068] When the open-close cover (45) is in the position shown in Fig. 4(C), the entire air supply communication port (41a) overlaps with the air supply opening (46), and the entire air exhaust communication port (42a) overlaps with the air exhaust opening (47). Therefore, the area of ​​the portion of the air supply communication port (41a) that overlaps with the air supply opening (46) (the portion marked with dots in Fig. 4(C)) and the area of ​​the portion of the air exhaust communication port (42a) that overlaps with the air exhaust opening (47) (the portion marked with dots in Fig. 4(C)) are both maximized. In other words, the air supply passage (41) and the air exhaust passage (42) are fully open. Therefore, in this state, the air supply flow rate and the air exhaust flow rate are both at their maximum.

[0069] When the open-close cover (45) is in the position shown in Fig. 4(B), a part of the intake communication port (41a) overlaps with the intake opening (46), and a part of the exhaust communication port (42a) overlaps with the exhaust opening (47). Therefore, the area of ​​the part of the intake communication port (41a) that overlaps with the intake opening (46) (the dotted part in Fig. 4(B)) and the area of ​​the part of the exhaust communication port (42a) that overlaps with the exhaust opening (47) (the dotted part in Fig. 4(B)) are each intermediate areas smaller than the maximum. Therefore, in this state, the intake air flow rate and the exhaust air flow rate are each intermediate flow rates greater than zero and smaller than the maximum flow rate.

[0070] -Air conditioning equipment inside the storehouse- The internal air conditioner (100) is provided in a transport refrigeration unit (10) for so-called controlled atmosphere (CA) transport. The internal air conditioner (100) adjusts the composition of air in a storage space (5) of a transport container (1).

[0071] 5, the internal air conditioner (100) includes a filter unit (220), a main unit (200), a gas supply pipe (275), a gas exhaust pipe (276), a sensor unit (160), and a ventilation exhaust pipe (150). The internal air conditioner (100) is a so-called PSA (Pressure Swing Adsorption) type gas separation device.

[0072] The indoor air conditioning device (100) generates a gas to be treated by treating atmospheric air, which is the air outside the container. Specifically, the indoor air conditioning device (100) separates the outside air into a nitrogen-rich gas having a higher nitrogen concentration and a lower oxygen concentration than the outside air, and an oxygen-rich gas having a lower nitrogen concentration and a higher oxygen concentration than the outside air. The nitrogen-rich gas is a first gas, and the oxygen-rich gas is a second gas. The nitrogen-rich gas is a low-oxygen gas having a lower oxygen concentration than the air outside the container. The oxygen concentration of the nitrogen-rich gas is, for example, about 3%.

[0073] <Filter unit, outside air pipe> The filter unit (220) is a box-shaped member. The filter unit (220) is installed in the external equipment room (28) of the transport refrigeration system (10). The filter unit (220) includes an air filter (221). The air filter (221) is a filter for trapping dust, salt, and the like contained in the external air. The air filter (221) of this embodiment is a breathable and waterproof membrane filter.

[0074] The filter unit (220) is connected to the main unit (200) through an outside air pipe (241). One end of the outside air pipe (241) is connected to the filter unit (220). The other end of the outside air pipe (241) is connected to an air pump (231) described below. The outside air pipe (241) guides outside air (atmosphere) that has passed through the air filter (221) to the air pump (231).

[0075] <Main unit> The main unit (200) is installed in the external equipment room (28) of the transport refrigeration system (10). The main unit (200) includes an air pump (231), a first adsorption column (234), a second adsorption column (235), a first switching valve (232), a second switching valve (233), and a unit case (201) that houses these components. The unit case (201) houses an inlet pipe (242), a suction pipe (243), a first gas pipe (244), and a second gas pipe (245).

[0076] <air pump> The air pump (231) includes a pressurized pump (231a), a reduced pressure side pump (231b), and a drive motor (231c). The pressurized pump (231a) and the reduced pressure side pump (231b) each suck in and discharge air. The pressurized pump (231a) and the reduced pressure side pump (231b) are connected to a drive shaft of a single drive motor (231c). In the air pump (231), both the pressurized pump (231a) and the reduced pressure side pump (231b) are driven by the single drive motor (231c).

[0077] The other end of the outside air pipe (241) is connected to the suction port of the pressurizing pump (231a). One end of an introduction pipe (242) is connected to the discharge port of the pressurizing pump (231a). The pressurizing pump (231a) supplies the air to be treated sucked from the outside air pipe (241) to the first adsorption column (234) and the second adsorption column (235) through the introduction pipe (242).

[0078] A suction pipe (243) is connected to the suction port of the decompression-side pump (231b). A first gas pipe (244) is connected to the discharge port of the decompression-side pump (231b). The decompression-side pump (231b) discharges gas sucked from the first adsorption column (234) and the second adsorption column (235) through the suction pipe (243) to the first gas pipe (244).

[0079] <Introduction pipe> The inlet pipe (242) is a pipe that guides the air to be treated discharged from the pressurizing pump (231a) to the first adsorption column (234) and the second adsorption column (235). One end of the inlet pipe (242) is connected to the discharge port of the pressurizing pump (231a). The other end of the inlet pipe (242) branches into two branch pipes, one of which is connected to the first selector valve (232) and the other of which is connected to the second selector valve (233).

[0080] <Suction tube> The suction pipe (243) is a pipe that guides the gas flowing out from the first adsorption column (234) and the second adsorption column (235) to the pressure reduction pump (231b). One end of the suction pipe (243) is connected to the suction port of the pressure reduction pump (231b). The other end of the suction pipe (243) branches into two branch pipes, one of which is connected to the first switch valve (232) and the other of which is connected to the second switch valve (233).

[0081] <First Gas Pipe> The first gas pipe (244) is a pipe through which the nitrogen-enriched gas discharged from the pressure-reducing pump (231b) flows. The first gas pipe (244) constitutes a first gas passage through which the nitrogen-enriched gas flows. One end of the first gas pipe (244) is connected to a discharge port of the pressure-reducing pump (231b). The other end of the first gas pipe (244) is connected to the gas supply pipe (275).

[0082] The first gas pipe (244) is provided with a check valve (264). The check valve (264) allows gas to flow only in a direction from one end to the other end of the first gas pipe (244) and blocks gas from flowing in the opposite direction.

[0083] <Switching valve> Each of the first switching valve (232) and the second switching valve (233) is a switching valve having three ports. Each of the first switching valve (232) and the second switching valve (233) is configured to be switched between a first state (a state shown by a solid line in FIG. 3) in which the first port communicates with the second port and is cut off from the third port, and a second state (a state shown by a dashed line in FIG. 3) in which the first port communicates with the third port and is cut off from the second port.

[0084] The first switch valve (232) has a first port connected to one end of the first adsorption column (234). The first switch valve (232) has a second port connected to a branch pipe of the introduction pipe (242) and a third port connected to a branch pipe of the suction pipe (243). The first switch valve (232) switches the first adsorption column (234) between a state where it is connected to the pressurization pump (231a) and a state where it is connected to the depressurization pump (231b).

[0085] The second selector valve (233) has a first port connected to one end of the second adsorption column (235). A branch pipe of the inlet pipe (242) is connected to a second port of the second selector valve (233), and a branch pipe of the suction pipe (243) is connected to a third port of the second selector valve (233). The second selector valve (233) switches the second adsorption column (235) between a state where it is connected to the pressurization pump (231a) and a state where it is connected to the depressurization pump (231b).

[0086] <Suction tube> The first adsorption column (234) and the second adsorption column (235) each include a cylindrical container with both ends closed and an adsorbent filled in the container. The adsorption columns (234, 235) use the adsorbent to separate the air to be treated (outside the chamber air in this embodiment) into an oxygen-enriched gas and a nitrogen-enriched gas.

[0087] The adsorbent filled in the adsorption columns (234, 235) has the property of adsorbing nitrogen and water (water vapor) in the air to be treated when the pressure is higher than atmospheric pressure, and desorbing nitrogen and water when the pressure is lower than atmospheric pressure. One example of an adsorbent having such a property is porous zeolite having pores with a pore size smaller than the molecular diameter of a nitrogen molecule (3.0 angstroms) and larger than the molecular diameter of an oxygen molecule (2.8 angstroms).

[0088] The first adsorption column (234) and the second adsorption column (235), together with the first switching valve (232) and the second switching valve (233), constitute an air treatment section (95).

[0089] <Second Gas Pipe> The second gas pipe (245) includes a trunk pipe (246), a first branch pipe (247a), and a second branch pipe (247b). The second gas pipe (245) constitutes a second gas passage through which the oxygen-enriched gas flows.

[0090] The first branch pipe (247a) is a pipe that connects the other end of the first adsorption cylinder (234) to one end of the trunk pipe (246). The second branch pipe (247b) is a pipe that connects the other end of the second adsorption cylinder (235) to one end of the trunk pipe (246). The first branch pipe (247a) and the second branch pipe (247b) are each provided with a check valve (261). Each check valve (261) allows air to flow in the direction out of the corresponding adsorption cylinder (234, 235) and blocks air from flowing in the opposite direction.

[0091] As described above, the first branch pipe (247a) and the second branch pipe (247b) are connected to one end of the trunk pipe (246). The other end of the trunk pipe (246) is connected to a gas exhaust pipe (276) described below. The trunk pipe (246) is provided with an orifice (263) and a check valve (262) in this order from one end to the other. The check valve (262) allows air to flow from one end of the trunk pipe (246) to the other end and blocks air from flowing in the opposite direction.

[0092] <Purge tube> A purge pipe (250) is connected to each of the first branch pipe (247a) and the second branch pipe (247b) of the second gas pipe (245). One end of the purge pipe (250) is connected to the first branch pipe (247a) and the other end is connected to the second branch pipe (247b). One end of the purge pipe (250) is connected to the first branch pipe (247a) between the first adsorption column (234) and the check valve (261). The other end of the purge pipe (250) is connected to the second branch pipe (247b) between the second adsorption column (235) and the check valve (261).

[0093] The purge pipe (250) is provided with a purge valve (251). The purge valve (251) is an on-off valve formed of a solenoid valve. The purge valve (251) is opened when equalizing the pressure in the first adsorption column (234) and the second adsorption column (235). In addition, an orifice (252) is provided on each side of the purge valve (251) in the purge pipe (250).

[0094] <Exhaust connection pipe> An exhaust connection pipe (271) is connected to the first gas pipe (244). One end of the exhaust connection pipe (271) is connected to the first gas pipe (244) and the other end is connected to the second gas pipe (245). One end of the exhaust connection pipe (271) is connected to the first gas pipe (244) between the pressure reducing pump (231b) and the check valve (264). The other end of the exhaust connection pipe (271) is connected to one end of the gas exhaust pipe (276).

[0095] The exhaust connection pipe (271) is provided with a gas exhaust valve (272). The gas exhaust valve (272) is an on-off valve formed of a solenoid valve. When the gas exhaust valve (272) is opened, the nitrogen-enriched gas flowing through the first gas pipe (244) is exhausted to the outside of the container body (2).

[0096] <Gas supply pipe> As described above, one end of the gas supply pipe (275) is connected to the first gas pipe (244). The gas supply pipe (275) extends to the outside of the unit case (201). The other end of the gas supply pipe (275) opens into the internal air flow path (29) of the transport refrigeration unit (10) downstream of the internal fan (35). The gas supply pipe (275) is a pipe for introducing the gas flowing in from the one end into the container body (2).

[0097] A gas supply valve (273) is provided on the gas supply pipe (275). The gas supply valve (273) is an on-off valve formed of a solenoid valve.

[0098] <Gas exhaust pipe> As described above, one end of the gas exhaust pipe (276) is connected to the trunk pipe (246) of the second gas pipe (245) and the exhaust connection pipe (271). The gas exhaust pipe (276) extends to the outside of the unit case (201). The other end of the gas exhaust pipe (276) opens into the external equipment room (28) of the transport container (1). The gas exhaust pipe (276) is a pipe for exhausting gas that has flowed in from the one end of the gas exhaust pipe (276) to the outside of the container body (2).

[0099] <Measurement piping> A measurement pipe (281) is connected to the first gas pipe (244). The measurement pipe (281) connects the first gas pipe (244) to the sensor unit (160). One end of the measurement pipe (281) is connected to the first gas pipe (244) downstream of the check valve (264). The other end of the measurement pipe (281) is connected to the sensor unit (160).

[0100] The measurement pipe (281) is provided with a measurement on-off valve (282). The measurement on-off valve (282) is an on-off valve formed of a solenoid valve. The measurement on-off valve (282) is opened when the air flowing through the first gas pipe (244) is to be sent to the sensor unit (160).

[0101] <Bypass pipe> A bypass connection pipe (255) is connected to the inlet pipe (242). The bypass connection pipe (255) is a pipe for supplying the outside air to the storage space (5) of the transport container (1) by bypassing the first adsorption column (234) and the second adsorption column (235). One end of the bypass connection pipe (255) is connected between the branch point of the inlet pipe (242) and the pressurizing pump (231a). The other end of the bypass connection pipe (255) is connected to one end of the gas supply pipe (275).

[0102] The bypass connecting pipe (255) is provided with a bypass valve (256). The bypass valve (256) is an on-off valve formed of a solenoid valve. The bypass valve (256) is opened when the outside air discharged by the pressurizing pump (231a) is supplied to the storage space (5) without changing the composition of the outside air.

[0103] <Sensor unit> The sensor unit (160) includes an oxygen sensor (161), a carbon dioxide sensor (162), and a sensor case (163). The sensor unit (160) is a detector that detects the concentrations of components of the interior air. The sensor unit (160) is provided in the secondary flow path (29b) of the interior air flow path (29).

[0104] The oxygen sensor (161) is, for example, a zirconia current type sensor that measures the oxygen concentration of a mixed gas such as air. The carbon dioxide sensor (162) is, for example, a non-dispersive infrared (NDIR) type sensor that measures the carbon dioxide concentration of a mixed gas such as air. The oxygen sensor (161) and the carbon dioxide sensor (162) are housed in a sensor case (163).

[0105] The sensor case (163) is a box-shaped member. The sensor case (163) includes an air filter (164). The air filter (164) is a membrane filter for capturing dust and other particles contained in the air inside the refrigerator. The air filter (164) filters the air inside the refrigerator flowing into the sensor case (163).

[0106] A measurement pipe (281) is connected to the sensor case (163). An outlet pipe (165) is also connected to the sensor case (163). An inlet end of the outlet pipe (165) is connected to the sensor case (163) and an outlet end of the outlet pipe (165) opens upstream of the internal fan (35) in the internal air flow path (29). In other words, the outlet end of the outlet pipe (165) opens into the primary flow path (29a) of the internal air flow path (29).

[0107] When the measurement on-off valve (282) is closed, the interior air flows through the sensor case (163). Specifically, the interior air flowing through the secondary flow path (29b) of the interior air flow path (29) passes through the air filter (164) and enters the sensor case (163), and after passing through the sensor case (163), flows through the outlet pipe (165) and into the primary flow path (29a) of the interior air flow path (29). Thus, when the measurement on-off valve (282) is closed, the oxygen sensor (161) measures the oxygen concentration of the interior air, and the carbon dioxide sensor (162) measures the carbon dioxide concentration of the interior air.

[0108] On the other hand, when the measurement on-off valve (282) is open, the gas flowing through the measurement pipe (281) flows inside the sensor case (163). Specifically, the gas flowing through the first gas pipe (244) or the bypass connection pipe (255) flows through the measurement pipe (281) into the sensor case (163), passes through the sensor case (163), flows through the outlet pipe (165), and flows into the primary flow path (29a) of the internal air flow path (29). Therefore, when the measurement on-off valve (282) is open, the oxygen sensor (161) measures the oxygen concentration of the gas flowing from the measurement pipe (281) into the sensor case (163), and the carbon dioxide sensor (162) measures the carbon dioxide concentration of the gas flowing from the measurement pipe (281) into the sensor case (163).

[0109] <Ventilation exhaust pipe> The ventilation exhaust pipe (150) is a pipe for discharging the air inside the transport container (1) to the external space. The ventilation exhaust pipe (150) penetrates the external wall portion (21) and the internal wall portion (22) of the transport refrigeration unit (10). The ventilation exhaust pipe (150) is provided with a ventilation exhaust valve (151). The ventilation exhaust valve (151) is an on-off valve formed of a solenoid valve.

[0110] -Gas supply operation of the interior air conditioning system- The interior air conditioning device (100) performs a gas supply operation. The gas supply operation is an operation in which a first gas is generated by processing the outside air and the first gas is supplied to the storage space (5) of the storage (2). In the gas supply operation, the ventilation exhaust valve (151) is opened.

[0111] In the gas supply operation, the internal air conditioner (100) alternately and repeatedly performs a first operation and a second operation. The internal air conditioner (100) alternately and repeatedly performs the first operation and the second operation for a predetermined switching time (e.g., 14 seconds). As a result, the air outside the compartment is separated into a nitrogen-enriched gas (first gas) and an oxygen-enriched gas (second gas) in the air treatment section (95) of the internal air conditioner (100).

[0112] <First action> 6, in the first operation, the first selector valve (232) is set to the first state, and the second selector valve (233) is set to the second state. In addition, in the first operation, the purge valve (251), the bypass valve (256), and the measurement on-off valve (282) are held in a closed state. In the first operation, the air pump (231) is operated to perform an adsorption operation for the first adsorption column (234) and a desorption operation for the second adsorption column (235).

[0113] The pressurizing pump (231a) draws in outside air (atmosphere) through the outside air pipe (241), pressurizes the air, and supplies the pressurized outside air to the first adsorption column (234). In the first adsorption column (234), nitrogen and water (water vapor) contained in the supplied outside air are adsorbed by an adsorbent. As a result, the first adsorption column (234) generates an oxygen-enriched gas having a lower nitrogen concentration and a higher oxygen concentration than the outside air. The oxygen-enriched gas flows from the first adsorption column (234) to a first branch pipe (247a) of the second gas pipe (245) and is then discharged to the outside space (6) through a gas exhaust pipe (276).

[0114] On the other hand, the decompression-side pump (231b) draws gas from the second adsorption column (235). In the second adsorption column (235), the internal pressure is reduced, and nitrogen and water are desorbed from the adsorbent. As a result, a nitrogen-rich gas having a higher nitrogen concentration and a lower oxygen concentration than the air outside the chamber is generated in the second adsorption column (235). The nitrogen-rich gas flows from the second adsorption column (235) into the suction pipe (243) and is sucked into the decompression-side pump (231b). The decompression-side pump (231b) pressurizes the sucked nitrogen-rich gas and discharges it into the first gas pipe (244). The nitrogen-rich gas flowing through the first gas pipe (244) is supplied to the storage space (5) of the storage (2) through the gas supply pipe (275).

[0115] <Second action> 7, in the second operation, the first selector valve (232) is set to the second state, and the second selector valve (233) is set to the first state. In addition, in the second operation, the purge valve (251), the bypass valve (256), and the measurement on-off valve (282) are held in a closed state. In the second operation, the air pump (231) is operated to perform a desorption operation for the first adsorption column (234) and an adsorption operation for the second adsorption column (235).

[0116] The pressurizing pump (231a) draws in outside air (atmosphere) through the outside air pipe (241), pressurizes the air, and supplies the pressurized outside air to the second adsorption column (235). In the second adsorption column (235), nitrogen and water (water vapor) contained in the supplied outside air are adsorbed by an adsorbent. As a result, the second adsorption column (235) generates an oxygen-enriched gas having a lower nitrogen concentration and a higher oxygen concentration than the outside air. The oxygen-enriched gas flows from the second adsorption column (235) to the second branch pipe (247b) of the second gas pipe (245) and is then discharged to the outside space (6) through the gas exhaust pipe (276).

[0117] On the other hand, the decompression-side pump (231b) draws gas from the first adsorption column (234). In the first adsorption column (234), the internal pressure is reduced, and nitrogen and water are desorbed from the adsorbent. As a result, a nitrogen-rich gas having a higher nitrogen concentration and a lower oxygen concentration than the air outside the chamber is generated in the first adsorption column (234). The nitrogen-rich gas flows from the first adsorption column (234) into the suction pipe (243) and is sucked into the decompression-side pump (231b). The decompression-side pump (231b) pressurizes the sucked nitrogen-rich gas and discharges it into the first gas pipe (244). The nitrogen-rich gas flowing through the first gas pipe (244) is supplied to the storage space (5) of the storage (2) through the gas supply pipe (275).

[0118] -Air intake operation of the interior air conditioning system- The interior air conditioner (100) performs an air introduction operation, which is an operation for supplying outside air, i.e., atmospheric air, to the storage space (5) of the storage (2) as is, without changing its composition.

[0119] 8, in the air introduction operation, both the first selector valve (232) and the second selector valve (233) are set to the second state. In addition, in the air introduction operation, the gas supply valve (273) and the bypass valve (256) are held in an open state, and the remaining on-off valves (251, 272, 282) are held in a closed state. In addition, in the air introduction operation, the air pump (231) is operated, and the ventilation exhaust valve (151) is opened.

[0120] The pressurizing pump (231a) draws in outside air (atmosphere) through the outside air pipe (241), pressurizes the air, and discharges the pressurized outside air to the inlet pipe (242). The outside air discharged from the pressurizing pump (231a) flows through the inlet pipe (242), the bypass connecting pipe (255), and the gas supply pipe (275) in this order, and is supplied to the inside air flow path (29). In this manner, in the air inlet operation, air having the same composition as the atmosphere is supplied to the storage space (5) of the transport container (1).

[0121] The decompression-side pump (231b) sucks gas from both the first adsorption column (234) and the second adsorption column (235) and discharges the sucked gas to the first gas pipe (244). The gas discharged from the decompression-side pump (231b) to the first gas pipe (244) flows into the gas supply pipe (275) and is supplied to the internal air flow path (29) together with the outside air that flows into the gas supply pipe (275) from the bypass connection pipe (255).

[0122] When the decompression-side pump (231b) sucks gas from the first adsorption column (234) and the second adsorption column (235), the pressure in the first adsorption column (234) and the second adsorption column (235) gradually decreases. When the air introduction operation continues for a certain period of time (e.g., 45 seconds), the flow rate of gas sucked by the decompression-side pump (231b) becomes substantially zero.

[0123] -Controller- 9, the controller (110) includes a microcomputer (111) mounted on a control board, and a memory device (112) that stores software for operating the microcomputer (111). The memory device (112) is a semiconductor memory.

[0124] The controller (110) controls the components of the interior air conditioner (100). Measurement values ​​of the oxygen sensor (161) and the carbon dioxide sensor (162) are input to the controller (110). The controller (110) controls the air pump (231), the first selector valve (136), and the second selector valve (137). The controller (110) also controls the ventilation exhaust valve (151), the purge valve (251), the bypass valve (256), the gas exhaust valve (272), the gas supply valve (273), and the measurement on-off valve (282).

[0125] The controller (110) controls the ventilation device (40). Specifically, the controller (110) adjusts the opening degree of the air supply communication port (41a) and the air exhaust communication port (42a) by rotating the opening / closing cover (45) of the ventilation device (40). Changing the opening degree of the air supply communication port (41a) changes the flow rate of outside air supplied to the storage space (5) through the air supply passage (41). Changing the opening degree of the air exhaust communication port (42a) changes the flow rate of inside air discharged to the outside space (6) through the air exhaust passage (42).

[0126] -Controller operation (overview)- The control operation performed by the controller (110) will now be outlined.

[0127] <Reduced oxygen concentration mode> When the air composition adjustment device (90) starts operating, the controller (110) executes an oxygen concentration reduction mode. The oxygen concentration reduction mode is a control mode for controlling the air composition adjustment device (90) so that the oxygen concentration of the air inside the storage compartment is reduced from the oxygen concentration of the ambient air (21%) to a set value SP_O2 of the oxygen concentration. The set value SP_O2 of the oxygen concentration is a sixth predetermined value. The oxygen concentration reduction mode is the process from step ST1 to step ST2 in the flow diagram of FIG. 10.

[0128] <Composition maintenance mode> When the oxygen concentration reduction mode is completed, the controller (110) then executes a composition maintenance mode. The composition maintenance mode is a control mode for controlling the air composition adjustment device (90) so that the oxygen concentration and carbon dioxide concentration of the inside air are maintained within their respective allowable ranges. The composition maintenance mode corresponds to the processes from step ST3 to step ST11 in the flow diagram of FIG. 10.

[0129] In this embodiment, the allowable range of the oxygen concentration is equal to or greater than SP_O2-α and equal to or less than SP_O2+α (SP_O2-α≦M_O2≦SP_O2+α). The constant α is, for example, 1%. The measured oxygen concentration value M_O2 is a value detected by the oxygen sensor (161). The set oxygen concentration value SP_O2 is input to the controller (110) by, for example, a manager of the transport refrigeration system (10). The set oxygen concentration value SP_O2 is, for example, 3%. The set oxygen concentration value SP_O2 is set to a value according to the type of fruit or vegetable stored in the storage space (5).

[0130] The allowable range of the carbon dioxide concentration is equal to or greater than SP_CO2-β and equal to or less than SP_CO2+β (SP_CO2-β≦M_CO2≦SP_CO2+β). The constant β is, for example, 1%. The measured carbon dioxide concentration value M_CO2 is the detection value of the carbon dioxide sensor (162). The set value SP_CO2 of the carbon dioxide concentration is input to the controller (110) by, for example, the manager of the transport refrigeration system (10). The set value SP_CO2 of the carbon dioxide concentration is, for example, 5%. The set value SP_CO2 of the carbon dioxide concentration is set to a value according to the type of fruit or vegetable stored in the storage space (5).

[0131] The controller (110) selectively executes a first control mode and a second control mode in the composition maintaining mode.

[0132] <First control mode> The first control mode is a control mode in which the indoor air conditioning device (100) is operated with the supply and exhaust of air by the ventilation device (40) stopped. The first control mode is a one-way operation mode. The first control mode corresponds to the processes from step ST3 to step ST5 in the flow diagram of FIG. 10. In the first control mode, the controller (110) controls the operation of the indoor air conditioning device (100) so that the oxygen concentration and carbon dioxide concentration of the indoor air are maintained within their respective allowable ranges.

[0133] <Second control mode> The second control mode is a control mode in which the internal air conditioner (100) performs a gas supply operation and the ventilation device (40) performs both air supply and exhaust. The second control mode is a dual operation mode. The second control mode corresponds to the processes from step ST7 to step ST11 in the flow diagram of Fig. 10. The second control mode is executed when, during the composition maintenance mode, it is necessary to reduce the carbon dioxide concentration in the internal air and to suppress an excessive increase in the oxygen concentration in the internal air.

[0134] In the second control mode, the controller (110) operates both the internal air conditioner (100) and the ventilation device (40) to ensure the amount of carbon dioxide discharged from the storage space (5), and keeps the increase in oxygen concentration in the internal air low by causing the internal air conditioner (100) to perform a gas supply operation.

[0135] -Controller operation (details)- The control operation performed by the controller (110) will now be described in detail with reference to the flow chart of FIG.

[0136] <Step ST1> As described above, the controller (110) executes the reduced oxygen concentration mode when the air composition adjustment device (90) begins operation.

[0137] In the process of step ST1, the controller (110) sets the opening / closing cover (45) of the ventilation device (40) to a position that completely covers the air supply communication port (41 a) and the exhaust communication port (42 a). In this state, both the air supply communication port (41 a) and the exhaust communication port (42 a) are fully closed, and the ventilation device (40) neither supplies nor exhausts air.

[0138] In the process of step ST1, the controller (110) causes the internal air conditioning device (100) to execute a gas supply operation. In the gas supply operation, the internal air conditioning device (100) alternately performs a first operation and a second operation to supply nitrogen-rich gas (first gas) to the storage space (5) of the container body (2). In the gas supply operation, the ventilation exhaust valve (151) is in an open state, and the air in the storage space (5) is exhausted to the external space (6) through the ventilation exhaust pipe (150). Therefore, the air in the storage space (5) is gradually replaced by the nitrogen-rich gas, and the oxygen concentration of the internal air in the storage space (5) gradually decreases.

[0139] <Step ST2> When the indoor air conditioning device (100) is performing the gas supply operation, the controller (110) performs the process of step ST2.

[0140] In the process of step ST2, the controller (110) acquires a detection value of the oxygen sensor (161). The detection value of the oxygen sensor (161) is a measured value M_O2 of the oxygen concentration of the inside air. The controller (110) compares the measured value M_O2 of the oxygen concentration with a set value SP_O2 of the oxygen concentration.

[0141] If the measured oxygen concentration M_O2 is higher than the set oxygen concentration SP_O2 (M_O2>SP_O2), the controller (110) causes the indoor air conditioner (100) to continue the gas supply operation and performs the process of step ST2 again. On the other hand, if the measured oxygen concentration M_O2 is equal to or lower than the set oxygen concentration SP_O2 (M_O2≦SP_O2), the controller (110) ends the oxygen concentration reduction mode and starts the first control mode, which is the composition maintenance mode.

[0142] <Step ST3> The controller (110), which has started the first control mode of the composition maintaining mode, performs the process of step ST3.

[0143] In the process of step ST3, the controller (110) sets the opening / closing cover (45) of the ventilation device (40) to a position that completely covers the intake air communication port (41a) and the exhaust air communication port (42a). In this state, both the intake air communication port (41a) and the exhaust air communication port (42a) are fully closed, and the ventilation device (40) neither supplies nor exhausts air. If the intake air communication port (41a) and the exhaust air communication port (42a) are already fully closed at the time when the process of step ST3 is started, the controller (110) maintains the position of the opening / closing cover (45) of the ventilation device (40) without changing it.

[0144] In the process of step ST3, the controller (110) controls the operation of the internal air conditioning device (100) so that the oxygen concentration and carbon dioxide concentration of the internal air are maintained within their respective permissible ranges.

[0145] In the process of step ST3, the controller (110) acquires a detection value of the oxygen sensor (161) and a detection value of the carbon dioxide sensor. The detection value of the oxygen sensor (161) is a measured value M_O2 of the oxygen concentration of the inside air. The detection value of the carbon dioxide sensor (162) is a measured value M_CO2 of the carbon dioxide concentration of the inside air.

[0146] In the processing of step ST3, the controller (110) switches the interior air conditioning device (100) between a state in which a gas supply operation is performed, a state in which an air introduction operation is performed, and a pause state in which neither the gas supply operation nor the air introduction operation is performed, based on the measured oxygen concentration value M_O2 and the measured carbon dioxide concentration value M_CO2.

[0147] When it is necessary to reduce the oxygen concentration in the interior air, the controller (110) causes the interior air conditioner (100) to perform a gas supply operation. When the interior air conditioner (100) performs the gas supply operation, nitrogen-rich gas is supplied to the storage space (5), and the oxygen concentration in the interior air decreases.

[0148] The controller (110) causes the internal air conditioning device (100) to perform an air introduction operation when it is necessary to increase the oxygen concentration of the internal air or when it is necessary to decrease the carbon dioxide concentration of the internal air. When the internal air conditioning device (100) performs an air introduction operation, outside air (atmosphere) is supplied as is to the storage space (5). Outside air, which is the atmosphere, has an oxygen concentration of 21% and a carbon dioxide concentration of 0.03%. Therefore, when outside air is supplied to the storage space (5), the oxygen concentration of the internal air increases and the carbon dioxide concentration of the internal air decreases.

[0149] The controller (110) puts the internal air conditioning device (100) into a suspended state when there is no need to adjust either the oxygen concentration or the carbon dioxide concentration of the internal air. In the suspended state, the internal air conditioning device (100) performs neither a gas supply operation nor an air introduction operation. Meanwhile, in the storage space (5), the stored fruits and vegetables respire. Therefore, while the internal air conditioning device (100) is in a suspended state, the oxygen concentration of the internal air gradually decreases, and the carbon dioxide concentration of the internal air gradually increases.

[0150] <Step ST4> The controller (110) performs the process of step ST4 while controlling the indoor air-conditioning device (100). In the process of step ST4, the controller (110) determines whether or not an instruction to end the composition maintenance mode has been input. The instruction to end the composition maintenance mode is input, for example, when the transportation of fruits and vegetables is terminated.

[0151] When an instruction to end the composition maintenance mode is input, the controller (110) ends the composition maintenance mode. On the other hand, when an instruction to end the composition maintenance mode is not input, the controller (110) continues the composition maintenance mode and performs the process of step ST5.

[0152] <Step ST5> In the process of step ST5, the controller (110) acquires the measured value M_O2 of the oxygen concentration in the storage and the measured value M_CO2 of the carbon dioxide concentration in the storage. Then, the controller (110) determines whether the first condition and the second condition are satisfied.

[0153] The first condition is the condition that "the measured value M_O2 of the oxygen concentration is less than or equal to the lower limit value SP_O2 - α of the allowable range of the oxygen concentration (M_O2 ≤ SP_O2 - α)". The lower limit value SP_O2 - α of the allowable range of the oxygen concentration is a first predetermined value. Note that the first condition may be the condition that "the measured value M_O2 of the oxygen concentration is lower than the first predetermined value (M_O2 < SP_O2 - α)".

[0154] The second condition is the condition that "the measured value M_CO2 of the carbon dioxide concentration is higher than the set value SP_CO2 of the carbon dioxide concentration (M_CO2 > SP_CO2)". The set value SP_CO2 of the carbon dioxide concentration is a second predetermined value.

[0155] When neither the first condition nor the second condition is satisfied, and when only one of the first condition and the second condition is satisfied, the controller (110) continues to perform the first control mode. Specifically, the controller (110) performs the process of step ST3 again.

[0156] On the other hand, when both the first condition and the second condition are satisfied, it is necessary to suppress an excessive increase in the oxygen concentration in the storage while reducing the carbon dioxide concentration in the storage. Therefore, the controller (110) ends the first control mode and starts the second control mode.

[0157] 〈Step ST6〉 The controller (110) that has started the second control mode performs the process of step ST6.

[0158] In the process of step ST6, the controller (110) causes the internal air conditioner (100) to perform a gas supply operation. The internal air conditioner (100) performing the gas supply operation supplies the nitrogen-rich gas generated in the air treatment unit (95) to the storage space (5). The nitrogen-rich gas is a gas separated from the outside air (atmosphere). Therefore, the carbon dioxide concentration of the nitrogen-rich gas is equal to or lower than the carbon dioxide concentration of the atmosphere (0.03%). Therefore, the internal air conditioner (100) performing the gas supply operation supplies the nitrogen-rich gas with a very low carbon dioxide concentration to the storage space (5).

[0159] In the process of step ST6, the controller (110) causes the ventilation device (40) to supply and exhaust air. Specifically, the controller (110) rotates the open-close lid (45) of the ventilation device (40) to open a portion of each of the supply air communication port (41a) and the exhaust air communication port (42a). At that time, the controller (110) moves the open-close lid (45) to a position where the areas of the openings of the supply air communication port (41a) and the exhaust air communication port (42a) become predetermined initial values.

[0160] When a portion of the supply air communication port (41a) is open, outside air is supplied to the storage space (5) through the supply air passage (41). When a portion of the exhaust air communication port (42a) is open, inside air that has passed through the exhaust air passage (42) is exhausted to the outside space (6).

[0161] The opening portion of the air supply communication port (41a) is a portion of the air supply communication port (41a) that overlaps with the air supply opening (46) of the open-close cover (45) (the portion marked with a dot in FIG. 4). The initial value of the opening portion of the air supply communication port (41a) is, for example, about 1 / 3 of the entire area of ​​the air supply communication port (41a). The opening portion of the exhaust communication port (42a) is a portion of the exhaust communication port (42a) that overlaps with the exhaust opening (47) of the open-close cover (45) (the portion marked with a dot in FIG. 4). The initial value of the opening portion of the exhaust communication port (42a) is, for example, about 1 / 3 of the entire area of ​​the exhaust communication port (42a).

[0162] <Step ST7> After the process of step ST6, the controller (110) performs a process of step ST7.

[0163] In the process of step ST7, the controller (110) determines whether the measured oxygen concentration value M_O2 has decreased. Specifically, the controller (110) stores the measured oxygen concentration value at the time when the process of step ST6 is completed as a reference oxygen concentration. In the process of step ST7, the controller (110) obtains the measured oxygen concentration value M_O2 at the time when a predetermined time (e.g., 60 minutes) has elapsed since the start of the process of step ST7, and compares the obtained measured oxygen concentration value M_O2 with the reference oxygen concentration.

[0164] If the acquired measured oxygen concentration value M_O2 is lower than the reference oxygen concentration, the measured oxygen concentration value M_O2 has decreased, and the controller (110) performs the process of step ST8. On the other hand, if the acquired measured oxygen concentration value M_O2 is equal to or higher than the reference oxygen concentration, the measured oxygen concentration value M_O2 has not decreased, and the controller (110) performs the process of step ST9.

[0165] <Step ST8> If the measured oxygen concentration value M_O2 is decreasing, it is necessary to increase the oxygen concentration of the air inside the storage compartment. Therefore, in the process of step ST8, the controller (110) increases the supply air flow rate of the ventilation device (40).

[0166] In the process of step ST8, the controller (110) increases the area of ​​the opening of the supply air communication port (41a) and the area of ​​the opening of the exhaust air communication port (42a) by rotating the opening / closing cover (45) of the ventilation device (40). When the area of ​​the opening of the supply air communication port (41a) increases, the flow rate of outside air supplied to the storage space (5) through the supply air passage (41) increases. As a result, the amount of oxygen supplied to the storage space (5) increases. When the area of ​​the opening of the exhaust air communication port (42a) increases, the flow rate of inside air discharged to the outside space (6) through the exhaust air passage (42) increases.

[0167] Upon completing the process of step ST8, the controller (110) performs the process of step ST7 again.

[0168] <Step ST9> If the measured oxygen concentration M_O2 has not decreased, there is no need to increase the oxygen concentration of the inside air, and in this case, the controller (110) performs the process of step ST9.

[0169] In the process of step ST9, the controller (110) calculates the rate of increase of the measured oxygen concentration value M_O2. Specifically, the controller (110) obtains the measured oxygen concentration value M_O2 at the start of the process of step ST9 and the measured oxygen concentration value M_O2 at a predetermined time (e.g., 60 minutes) after the start of the process of step ST9, and calculates the amount of change in the measured oxygen concentration value M_O2 per unit time (i.e., the rate of increase of the measured oxygen concentration value M_O2).

[0170] In the process of step ST9, the controller (110) determines whether a third condition is satisfied. The third condition is that "the rate of increase of the measured oxygen concentration value M_O2 is higher than a reference rate of increase." The reference rate of increase is a third predetermined value. The reference rate of increase is recorded in advance in the controller (110). The controller (110) may be configured to change the reference rate of increase depending on the operating state of the air composition adjusting device or the state of the air inside the storage compartment.

[0171] If the third condition is satisfied, the controller (110) performs the process of step ST10. On the other hand, if the third condition is not satisfied, the controller (110) performs the process of step ST11.

[0172] <Step ST10> If the rate of increase of the measured oxygen concentration value M_O2 is higher than the reference rate of increase, the flow rate of outside air supplied by the ventilation device (40) to the storage space (5) is too high. If the flow rate of outside air supplied by the ventilation device (40) to the storage space (5) is too high, the oxygen concentration of the inside air will increase too much. In this case, the controller (110) performs the process of step ST10.

[0173] In the process of step ST10, the controller (110) rotates the opening / closing lid (45) of the ventilation device (40) to reduce the area of ​​the opening of the supply air communication port (41a) and the area of ​​the opening of the exhaust air communication port (42a). When the area of ​​the opening of the supply air communication port (41a) is reduced, the flow rate of outside air supplied to the storage space (5) through the supply air passage (41) is reduced. As a result, the amount of oxygen supplied to the storage space (5) is reduced. When the area of ​​the opening of the exhaust air communication port (42a) is reduced, the flow rate of inside air discharged to the outside space (6) through the exhaust air passage (42) is reduced.

[0174] Upon completing the process of step ST10, the controller (110) performs the process of step ST7 again.

[0175] <Step ST11> When the rate of increase of the measured oxygen concentration value M_O2 is equal to or less than the reference rate of increase, the flow rate of the outside air supplied to the storage space (5) by the ventilation device (40) and the flow rate of the inside air exhausted from the storage space (5) by the ventilation device (40) are appropriate. In this case, the controller (110) performs the process of step ST11.

[0176] In the process of step ST11, the controller (110) determines whether the fourth condition is met and whether the fifth condition is met.

[0177] The fourth condition is that "the measured oxygen concentration value M_O2 is equal to or greater than the upper limit value SP_O2+α of the allowable range of oxygen concentration." The upper limit value SP_O2+α of the allowable range of oxygen concentration is a fourth predetermined value. The fourth predetermined value, "the upper limit value SP_O2+α of the allowable range of oxygen concentration," is higher than the first predetermined value, "the lower limit value SP_O2-α of the allowable range of oxygen concentration." The fourth condition may also be that "the measured oxygen concentration value M_O2 is higher than the fourth predetermined value."

[0178] The fifth condition is that "the measured carbon dioxide concentration M_CO2 is equal to or lower than the lower limit SP_CO2-β of the allowable range of carbon dioxide concentration." The lower limit SP_CO2-β of the allowable range of carbon dioxide concentration is a fifth predetermined value. The fifth predetermined value, "the lower limit SP_CO2-β of the allowable range of carbon dioxide concentration," is lower than the second predetermined value, "the set value SP_CO2 of carbon dioxide concentration." The fifth condition may also be that "the measured carbon dioxide concentration M_CO2 is lower than the fifth predetermined value."

[0179] If the fourth condition is not satisfied, the oxygen concentration of the air inside the refrigerator needs to be increased. If the fifth condition is not satisfied, the carbon dioxide concentration of the air inside the refrigerator needs to be decreased. Therefore, if neither the fourth nor the fifth condition is satisfied, the controller (110) continues the second control mode. Specifically, the controller (110) performs the process of step ST7 again.

[0180] If the fourth condition is satisfied, there is no need to increase the oxygen concentration in the air inside the refrigerator. If the fifth condition is satisfied, there is no need to decrease the carbon dioxide concentration in the air inside the refrigerator. Therefore, if one or both of the fourth and fifth conditions are satisfied, the controller (110) ends the second control mode and starts the first control mode. Specifically, the controller (110) performs the process of step ST3 again.

[0181] -Features of the embodiment- The controller (110) of the air composition adjusting device (90) of this embodiment operates in a first control mode and a second control mode in the composition maintenance mode. Therefore, even when fruits and vegetables, which have a relatively high respiration rate, are stored in the storage space (5), the oxygen concentration and carbon dioxide concentration of the air inside the storage space can be kept within their respective permissible ranges (the ranges of SP_O2±α and SP_CO2±β) for as long as possible.

[0182] An example of fruit or vegetable with a relatively high respiration rate is climatellic fruit. Climatellic fruits have a characteristic in which their respiration rate increases rapidly during the ripening process. Climatellic fruits include bananas, avocados, apples, peaches, etc. The transport container (1) equipped with the air composition adjustment device (90) of this embodiment is suitable for storing and transporting fruit or vegetable with a relatively high respiration rate (e.g., climatellic fruits).

[0183] The reasons why the air composition adjustment device (90) of the present embodiment provides the above-mentioned effects will be explained below.

[0184] When the fruits and vegetables stored in the storage space (5) breathe, the amount of carbon dioxide contained in the air inside the storage space (5) increases, and as a result, the carbon dioxide concentration in the air inside the storage space (5) increases. In order to suppress the increase in the carbon dioxide concentration in the air inside the storage space (5), it is necessary to supply gas with a low carbon dioxide concentration to the storage space (5) and exhaust the air inside the storage space (5) with a high carbon dioxide concentration to the outside.

[0185] The outside air, which is atmospheric air, has a carbon dioxide concentration of 0.03%. Therefore, by making the ventilation device (40) supply and exhaust air, outside air with a very low carbon dioxide concentration is supplied to the storage space (5) and inside air with a high carbon dioxide concentration is exhausted from the storage space (5), thereby preventing an increase in the carbon dioxide concentration of the inside air.

[0186] On the other hand, the oxygen concentration of the outside air, which is atmospheric air, is 21%. Therefore, when the ventilation device (40) is caused to supply air in order to suppress an increase in the carbon dioxide concentration of the inside air, outside air with a relatively high oxygen concentration is supplied to the storage space (5).

[0187] When fruits and vegetables respire, oxygen in the air inside the storage compartment is consumed. For this reason, it is necessary to supply a certain amount of oxygen to the storage space (5). However, when the amount of respiration of the fruits and vegetables is very large, it is necessary to greatly increase the flow rate of outside air supplied to the storage space (5) in order to suppress an increase in the carbon dioxide concentration in the air inside the storage compartment. If the flow rate of outside air supplied to the storage space (5) is increased, the amount of oxygen supplied to the storage space (5) may exceed the amount of oxygen consumed by the respiration of the fruits and vegetables, and the oxygen concentration in the air inside the storage compartment may increase.

[0188] Therefore, the controller (110) of this embodiment ends the first control mode and starts the second control mode when the first condition and the second condition shown in step ST5 of Fig. 10 are satisfied while the first control mode is being executed. In the second control mode, the controller (110) causes the indoor air conditioning device (100) to perform a gas supply operation and causes the ventilation device (40) to supply and exhaust air.

[0189] During execution of the second control mode, the ventilation device (40) supplies outside air to the storage space (5), and the internal air conditioning device (100) supplies nitrogen-rich gas to the storage space (5). The oxygen concentration of the nitrogen-rich gas is significantly lower than the oxygen concentration of the air. Therefore, by supplying both the outside air and the nitrogen-rich gas to the storage space (5), it is possible to reduce the amount of oxygen supplied to the storage space (5) without reducing the flow rate of the gas supplied to the storage space (5).

[0190] In this way, when the controller (110) of this embodiment operates in the second control mode, the flow rate of the gas supplied to the storage space (5) is maintained, thereby suppressing an increase in the carbon dioxide concentration in the air inside the storage space, and at the same time, the amount of oxygen supplied to the storage space (5) is reduced, thereby preventing the oxygen concentration in the air inside the storage space from increasing too much. As a result, the time during which the oxygen concentration and carbon dioxide concentration in the air inside the storage space are maintained within their respective allowable ranges can be extended, and the freshness of fruits and vegetables stored in the storage space (5) can be maintained for a long period of time.

[0191] In particular, in the second control mode, the controller (110) of this embodiment increases the supply air flow rate of the ventilation device (40) when the oxygen concentration of the interior air decreases (see steps ST7 and ST8 in FIG. 10), and decreases the supply air flow rate of the ventilation device (40) when the oxygen concentration of the interior air increases too quickly (see steps ST9 and ST10 in FIG. 10). This makes it possible to prevent a decrease in the oxygen concentration of the interior air and an excessive increase in the oxygen concentration of the interior air, and at the same time, suppress an increase in carbon dioxide in the interior air.

[0192] -Modifications of the embodiment- The following modifications may be applied to the air composition adjustment device (90) of the above embodiment. The following modifications may be combined or substituted as appropriate as long as the functionality of the air composition adjustment device (90) is not impaired.

[0193] First Modified Example The ventilation device (40) of the above embodiment may be configured to adjust the flow rate of outside air supplied to the storage space (5) (intake air flow rate) and the flow rate of inside air exhausted to the outside space (6) (exhaust air flow rate) by adjusting the rotation speed of the internal fan (35). In this modification, the controller (110) increases the intake air flow rate and the exhaust air flow rate of the ventilation device (40) by increasing the rotation speed of the internal fan (35). The controller (110) also decreases the intake air flow rate and the exhaust air flow rate of the ventilation device (40) by decreasing the rotation speed of the internal fan (35).

[0194] <Second Modification> The air treatment unit (95) of the interior air conditioner (100) of the above embodiment may be configured to separate outside air (atmosphere) into a nitrogen-rich gas (first gas) and an oxygen-rich gas (second gas) using a gas separation membrane. The gas separation membrane has a property that the permeation rate of nitrogen is lower than both the permeation rates of oxygen and carbon dioxide. Therefore, in the air treatment unit (95) of this modification, the outside air is separated into an oxygen-rich gas that has permeated the gas separation membrane and a nitrogen-rich gas that has not permeated the gas separation membrane.

[0195] <Third Modification> The air composition adjusting device (90) of the above embodiment may be provided in a stationary refrigerator or freezer. The air composition adjusting device (90) of the above embodiment may be provided in a land transport container transported by truck, rail, or the like. The air composition adjusting device (90) of the above embodiment may be provided in a refrigerated / freezer truck in which a box body forming a luggage compartment is integrated with the chassis. In this way, the storage facility equipped with the air composition adjusting device (90) of the above embodiment is not limited to a transport container for marine transport, but may be a transport container for land transport, a box body mounted on a truck forming a luggage compartment, or a stationary refrigerator or freezer.

[0196] Although the embodiments and modifications have been described above, it will be understood that various modifications of form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments and modifications may be appropriately combined or substituted as long as the functions of the subject of the present disclosure are not impaired. Furthermore, the descriptions "first", "second", ... in the specification and claims are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words. [Industrial Applicability]

[0197] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for air composition adjustment devices, refrigeration devices, and storage units. [Explanation of symbols]

[0198] 2. Storage 10 Refrigeration equipment 11 Refrigerant circuit 35 Interior fan 40 Ventilation system (air supply section) 41a Air supply connection port (air inlet) 90 Air Composition Control Device 95 Air Processing Unit 100 In-storage air conditioning device (composition adjustment section) 110 Controller 160 Sensor unit (detector) 161 Oxygen sensor 162 Carbon Dioxide Sensor

Claims

1. An air composition adjustment device (90) for adjusting the composition of air inside a storage compartment (2), a composition adjusting section (100) that processes outside air to generate a gas to be treated having a composition different from that of the outside air and supplies the gas to be treated to the storage compartment (2); an air supply section (40) that supplies the outside air to the storage compartment (2); a controller (110) that controls the composition adjustment unit (100) and the air supply unit (40), The controller (110) performs a dual operation mode of causing the air supply unit (40) to supply the outside air to the storage (2) and causing the composition adjustment unit (100) to supply the gas to be treated to the storage (2). Air composition regulator.

2. The gas to be treated generated by the composition adjusting section (100) contains a low-oxygen concentration gas having an oxygen concentration lower than that of the outside air, The controller (110) controls the composition regulator (100) to supply the low oxygen concentration gas to the storage (2) in the dual operation mode. The air composition conditioning device according to claim 1 .

3. a detector (160) for detecting the concentration of one or more components of the interior air; The controller (110) a one-way operation mode is performed in which the operation of the composition adjustment unit (100) is controlled based on the value detected by the detector (160) while the supply of the outside air to the storage unit (2) by the air supply unit (40) is stopped; Switching between the one-operation mode and the two-operation mode based on the detection value of the detector (160). The air composition conditioning device according to claim 1 .

4. The detector (160) includes an oxygen sensor (161) that detects an oxygen concentration in the interior air, and a carbon dioxide sensor (162) that detects a carbon dioxide concentration in the interior air, When the detection value of the oxygen sensor (161) is lower than a first predetermined value and the detection value of the carbon dioxide sensor (162) is higher than a second predetermined value during execution of the one-way operation mode, the controller (110) ends the one-way operation mode and executes the dual-way operation mode. The air composition conditioning device according to claim 3.

5. The air supply section (40) is capable of changing a flow rate of the outside air supplied to the storage compartment (2), When the detection value of the oxygen sensor (161) decreases during execution of the dual operation mode, the controller (110) increases the flow rate of the outside air supplied to the storage compartment (2) by the air supply section (40).

5. An air composition conditioning device according to claim 4.

6. The air supply section (40) is capable of changing a flow rate of the outside air supplied to the storage compartment (2), The controller (110) reduces the flow rate of the outside air supplied to the storage (2) by the air supply section (40) when the rate of increase in the detection value of the oxygen sensor (161) is higher than a third predetermined value during execution of the dual operation mode.

5. An air composition conditioning device according to claim 4.

7. the controller (110) terminates the dual operation mode and executes the single operation mode when the detection value of the oxygen sensor (161) is higher than a fourth predetermined value or when the detection value of the carbon dioxide sensor (162) is lower than a fifth predetermined value during execution of the dual operation mode, The fourth predetermined value is higher than the first predetermined value, and the fifth predetermined value is lower than the second predetermined value.

7. An air composition conditioning device according to claim 4.

8. The air supply section (40) includes an air inlet (41a) whose opening degree is variable, which connects the outside of the storage compartment (2) with the inside of the storage compartment (2); The controller (110) By increasing the opening degree of the air inlet (41a), the flow rate of the outside air supplied to the storage (2) by the air supply part (40) is increased, The flow rate of the outside air supplied to the storage (2) by the air supply unit (40) is reduced by reducing the opening degree of the air inlet (41a).

7. An air composition conditioning device according to claim 5 or 6.

9. The air supply section (40) an internal fan (35) for circulating internal air within the storage compartment (2) and an air inlet (41a) for communicating between the outside of the storage compartment (2) and an intake side area of ​​the internal fan (35) within the storage compartment (2); The controller (110) By increasing the rotation speed of the internal fan (35), the flow rate of the external air supplied to the storage compartment (2) by the air supply section (40) is increased; The rotation speed of the internal fan (35) is reduced to reduce the flow rate of the external air supplied to the storage compartment (2) by the air supply section (40).

7. An air composition conditioning device according to claim 5 or 6.

10. the composition adjustment unit (100) is capable of performing an adjustment operation of supplying the gas to be treated to the storage compartment (2) and an air introduction operation of supplying the outside air to the storage compartment (2); The controller (110), in the one-way operation mode, switches between a state in which the composition adjustment unit (100) performs the adjustment operation, a state in which the composition adjustment unit (100) performs the air introduction operation, and a state in which the composition adjustment unit (100) pauses without performing the adjustment operation or the air introduction operation, based on a value detected by the detector (160). The air composition conditioning device according to any one of claims 3 to 6.

11. The detector (160) includes an oxygen sensor (161) that detects the oxygen concentration of the air inside the storage compartment, The controller (110) an oxygen concentration reduction mode in which, while the supply of the outside air to the storage compartment (2) by the air supply unit (40) is stopped, the operation of the composition adjustment unit (100) is controlled so that the detection value of the oxygen sensor (161) decreases from the oxygen concentration of the outside air to a sixth predetermined value; a composition maintenance mode in which, after the oxygen concentration reduction mode is terminated, the operation of the composition adjustment unit (100) and the air supply unit (40) is controlled in order to maintain the composition of the interior air; While the composition maintaining mode is being executed, the both operation modes are executed. The air composition conditioning device according to claim 3.

12. The gas to be treated includes a first gas having a higher nitrogen concentration and a lower oxygen concentration than the outside air, and a second gas having a lower nitrogen concentration and a higher oxygen concentration than the outside air, The composition adjustment section (100) includes an air treatment section (95) that separates the outside air into the first gas and the second gas. The air composition conditioning device according to claim 1 .

13. the air treatment section (95) of the composition adjustment section (100) includes an adsorbent that adsorbs nitrogen, The composition adjustment section (100) performs an operation of generating the second gas by adsorbing nitrogen contained in the outside air to the adsorbent of the air treatment section (95), and an operation of generating the first gas by desorbing nitrogen from the adsorbent of the air treatment section (95). The air composition conditioning device according to claim 12.

14. An air composition conditioning device (90) according to any one of claims 1 to 6; a refrigerant circuit (11) for adjusting the temperature of the air inside the storage compartment by performing a refrigeration cycle. Refrigeration equipment.

15. A storage facility comprising a refrigeration system (10) according to claim 14.

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