Warehouse air conditioning equipment, refrigeration equipment and transport containers

Abstract

The adsorber (234, 235) of the air conditioning device (100) in the storage separates the air outside the storage into a first gas with a high nitrogen concentration and a low oxygen concentration and a second gas with a low nitrogen concentration and a high oxygen concentration. The air conditioning device (100) in the storage performs a lowering operation and an increasing operation. In the lowering operation, the first gas is introduced into the interior of the storage (2) through the first gas passage (244), and the oxygen concentration of the air in the storage is reduced. In the increasing operation, the second gas is introduced into the interior of the storage (2) through the second gas passage (245), and the oxygen concentration of the air in the storage is increased.

Description

Technical Field

[0001] The present invention relates to an in-store air conditioning device, a refrigeration device and a transport container. Background Art

[0002] Patent Document 1 discloses an in-store air conditioning device that adjusts the composition of in-store air in a transport container. The in-store air conditioning device adjusts the oxygen concentration and carbon dioxide concentration of in-store air in order to maintain the freshness of fruits and vegetables stored in the transport container.

[0003] The in-store air conditioning device of Patent Document 1 is a gas separation device of the so-called PSA (Pressure Swing Adsorption) method. The in-store air conditioning device includes an adsorption cylinder filled with an adsorbent. The in-store air conditioning device performs an adsorption action and a desorption action. The adsorption action is to supply air outside the store (atmosphere) to the adsorption cylinder so that nitrogen in the air outside the store is adsorbed on the adsorbent, and the desorption action is to desorb nitrogen from the adsorbent in the adsorption cylinder.

[0004] In order to reduce the oxygen concentration in the warehouse, the air conditioning device in the warehouse operates to supply the nitrogen-rich gas generated by the desorption action into the warehouse. In addition, due to the respiration of the fruits and vegetables stored in the warehouse, the oxygen concentration of the air in the warehouse gradually decreases. Therefore, in order to increase the oxygen concentration of the air in the warehouse, the air conditioning device in the warehouse operates to supply the air outside the warehouse (atmosphere) into the warehouse.

[0005] Patent Document 1: Japanese Patent Publication No. 2017-219287 Summary of the invention

[0006] -Technical problem to be solved by the invention-

[0007] As described above, the existing in-store air conditioning device supplies the air outside the storehouse (atmosphere) into the storehouse in order to increase the oxygen concentration of the in-store air. Therefore, in the existing in-store air conditioning device, it is impossible to make the "oxygen concentration of the gas supplied into the storehouse in order to increase the oxygen concentration of the in-store air" higher than the oxygen concentration of the atmosphere (21%), and as a result, it is impossible to shorten the "time required to increase the oxygen concentration of the in-store air to reach the target oxygen concentration".

[0008] The purpose of the present disclosure is to shorten the time required for an in-store air conditioning device to increase the oxygen concentration of in-store air.

[0009] -Technical solutions to solve technical problems-

[0010] A first aspect of the present disclosure is an in-store air conditioning device 100 for regulating the composition of in-store air inside a storage store 2, comprising adsorbers 234, 235, a first gas passage 244 and a second gas passage 245, the adsorbers 234, 235 having an adsorbent for adsorbing nitrogen, separating the out-of-store air outside the storage store into a first gas having a higher nitrogen concentration and a lower oxygen concentration than the out-of-store air and a second gas having a lower nitrogen concentration and a higher oxygen concentration than the out-of-store air, the first gas passage 244 being for the first gas to flow, and the second gas passage 245 being for the second gas to flow, the in-store air conditioning device 100 performing a lowering operation and a raising operation, the lowering operation being for introducing the first gas into the interior of the storage store 2 via the first gas passage 244 to reduce the oxygen concentration of the in-store air, and the raising operation being for introducing the second gas into the interior of the storage store 2 via the second gas passage 245 to increase the oxygen concentration of the in-store air.

[0011] The in-store air conditioning device 100 of the first aspect performs a lowering operation to reduce the oxygen concentration of the in-store air and an increasing operation to increase the oxygen concentration of the in-store air. In the increasing operation, a second gas having a lower nitrogen concentration and a higher oxygen concentration than the air outside the storehouse is introduced into the interior of the storage storehouse 2 through the second gas passage 245. Therefore, compared with the case where the air outside the storehouse is introduced into the interior of the storage storehouse 2 in order to increase the oxygen concentration of the in-store air, the rate of increase of the oxygen concentration of the in-store air becomes faster. As a result, the time required to increase the oxygen concentration of the in-store air is shortened.

[0012] In a second aspect of the present disclosure, based on the first aspect, the second gas passage 245 can be switched between an introduction state of introducing the second gas into the interior of the storage 2 and a discharge state of discharging the second gas to the outside of the storage 2 .

[0013] In the second aspect, the second gas passage 245 switches between an introduction state and an exhaust state. When the second gas passage 245 is in the introduction state, the second gas flowing through the second gas passage 245 is introduced into the interior of the storage 2. When the second gas passage 245 is in the exhaust state, the second gas flowing through the second gas passage 245 is exhausted to the outside of the storage 2.

[0014] According to a third aspect of the present disclosure, based on the second aspect, the second gas passage 245 includes a trunk passage 246, a supply passage 248a, the exhaust passage 248b, and a switching mechanism 249, wherein the trunk passage 246 is connected to the adsorbers 234 and 235, the supply passage 248a is in communication with the interior of the storage 2, and the exhaust passage 248b is in communication with the exterior of the storage 2. In the introduction state, the switching mechanism 249 enables the trunk passage 246 to communicate with the supply passage 248a; in the exhaust state, the switching mechanism 249 enables the trunk passage 246 to communicate with the exhaust passage 248b.

[0015] In the third aspect, the second gas passage 245 includes a switching mechanism 249. In the second gas passage 245 in the introduction state, the switching mechanism 249 connects the trunk passage 246 with the supply passage 248a, and the second gas is introduced into the interior of the storage 2 through the supply passage 248a. In the second gas passage 245 in the discharge state, the switching mechanism 249 connects the trunk passage 246 with the discharge passage 248b, and the second gas is discharged to the outside of the storage 2 through the discharge passage 248b.

[0016] The fourth aspect of the present disclosure, based on the above-mentioned second aspect or third aspect, includes an oxygen sensor 161 and a controller 110, wherein the oxygen sensor 161 measures the oxygen concentration of the air in the storage, and the controller 110 switches the second gas passage 245 to the introduction state and the exhaust state according to the measurement value of the oxygen sensor 161.

[0017] In the fourth aspect, the controller 110 switches the second gas passage 245 between the intake state and the exhaust state based on the measurement value of the oxygen sensor 161 (the actual measurement value of the oxygen concentration of the air in the storage compartment).

[0018] The fifth aspect of the present disclosure is based on any one of the first to fourth aspects mentioned above. During the lifting operation, the second gas is introduced into the interior of the storage 2 via the second gas passage 245, and the first gas is introduced into the interior of the storage 2 via the first gas passage 244.

[0019] In the fifth aspect, during the boost operation of the in-compartment air conditioning apparatus 100 , both the first gas and the second gas are introduced into the interior of the storage 2 .

[0020] According to a sixth aspect of the present disclosure, based on the fifth aspect, the in-store air conditioning device 100 includes a flow regulating mechanism 272 for regulating the flow of the first gas introduced into the interior of the storage store 2 during the lifting operation.

[0021] In the sixth aspect, the flow rate adjustment mechanism 272 adjusts the flow rate of the first gas introduced into the interior of the storage 2 during the lifting operation.

[0022] The seventh aspect of the present disclosure is based on the sixth aspect mentioned above. The air conditioning device 100 in the storage room includes a first gas exhaust passage 271, one end of which is connected to the first gas passage 244, and the other end is connected to the outside of the storage room 2. The flow regulating mechanism 272 is a valve arranged in the first gas exhaust passage 271.

[0023] In the seventh aspect, when the valve constituting the flow regulating mechanism 272 is open, a portion of the first gas is discharged to the outside of the storage 2 through the first gas discharge passage 271, and the remaining portion of the first gas is introduced into the storage 2. Therefore, when the flow rate of the first gas flowing through the first gas discharge passage 271 is changed by the valve constituting the flow regulating mechanism 272, the flow rate of the first gas introduced into the storage 2 changes accordingly.

[0024] The eighth aspect of the present disclosure is based on any one of the first to seventh aspects above, wherein the adsorber includes a first adsorber 234 and a second adsorber 235 respectively having the adsorbent, and the in-store air conditioning device 100 repeatedly and alternately performs a first action and a second action, wherein the first action is to supply the outside air to the first adsorber 234 so that the second gas flows out from the first adsorber 234 and the first gas flows out from the second adsorber 235, and the second action is to supply the outside air to the second adsorber 235 so that the second gas flows out from the second adsorber 235 and the first gas flows out from the first adsorber 234.

[0025] In the eighth aspect, the in-compartment air conditioning device 100 performs the first operation and the second operation alternately. In the first operation and the second operation, the outside air is separated into the first gas and the second gas, respectively.

[0026] A ninth aspect of the present disclosure is a refrigeration device 10 including the in-store air conditioning device 100 according to any one of the first to eighth aspects and a refrigerant circuit 11 that performs a refrigeration cycle to adjust the temperature of the in-store air.

[0027] In the refrigeration system (10) according to the ninth aspect, the air conditioning device (100) inside the storage room operates to adjust the composition of the air inside the storage room, and the refrigerant circuit (11) operates to adjust the temperature of the air inside the storage room.

[0028] The tenth aspect of the present disclosure is a transport container 1, comprising the refrigeration device 10 of the ninth aspect and a container body. The refrigeration device 10 is mounted on the container body, and the storage 2 is constituted by the container body.

[0029] In the transport container ( 1 ) of the tenth aspect, the refrigeration device ( 10 ) adjusts the composition and temperature of the air inside the container body ( 2 ). BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a cross-sectional view of a transport container according to an embodiment;

[0031] Figure 2 is a piping system diagram showing a refrigerant circuit of a transport refrigeration device according to an embodiment;

[0032] Figure 3 is a piping system diagram showing the structure of an in-store air conditioning device according to an embodiment;

[0033] Figure 4 is a block diagram showing the structure of a controller included in the in-store air conditioning device according to the embodiment;

[0034] Figure 5 The figure shows the interior air conditioning device performing the first action during the lowering operation. Figure 3 Quite a picture;

[0035] Figure 6 The figure shows the indoor air conditioning device performing the second action during the lowering operation. Figure 3 Quite a picture;

[0036] Figure 7 The present invention shows the indoor air conditioning device performing the first action in the lifting operation. Figure 3 Quite a picture;

[0037] Figure 8 The present invention shows the indoor air conditioning device performing the second action in the lifting operation. Figure 3 Quite a picture;

[0038] Fig. 9 The figure shows the indoor air conditioning device which performs the operation of introducing outside air. Figure 3 Quite a picture;

[0039] Fig.10 This is a flowchart showing the operation of the controller included in the in-store air conditioning apparatus according to the embodiment. DETAILED DESCRIPTION

[0040] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0041] The present invention discloses a transport container 1. The transport container 1 is a refrigerated container capable of performing temperature management in the container. The transport container 1 is used to transport fresh food (e.g., fruits, vegetables, flowers, etc.), and the fresh food breathes, absorbs oxygen (O2) in the air, and releases carbon dioxide (CO2).

[0042] like Figure 1 As shown, the transport container 1 includes a container body 2 and a transport refrigeration device 10. The transport refrigeration device 10 is installed on the container body 2. The transport container 1 is used for marine transportation. The transport container 1 is transported by a marine transport body such as a ship.

[0043] -Container body-

[0044] The container body 2 is a storage room for storing the above-mentioned fresh food.

[0045] The container body 2 is formed in a hollow box shape. The container body 2 is formed to be long in the horizontal direction. An opening is formed at one end of the length direction of the container body 2. The opening of the container body 2 is sealed by a transport refrigeration device 10. A storage space 5 for storing goods 6 is formed in the container body 2. The goods 6 are boxes containing fresh food.

[0046] A floor 3 for placing cargo 6 is arranged at the bottom of the storage space 5. An under-floor flow path 4 for allowing air blown out of the transport refrigeration device 10 to flow is formed between the floor 3 and the bottom plate of the container body 2. The under-floor flow path 4 is a flow path extending along the bottom plate of the container body 2 in the longitudinal direction of the container body 2. One end of the under-floor flow path 4 is connected to the air outlet 27 of the transport refrigeration device 10, and the other end is connected to the space above the floor 3 (that is, the space for storing cargo 6).

[0047] - Transport Refrigeration Units -

[0048] The transport refrigeration device (10) includes a casing (20), a refrigerant circuit (11) that performs a refrigeration cycle, an external fan (34), and an internal fan (35).

[0049] <shell>

[0050] The casing 20 includes an outer wall 21, an inner wall 22, a rear plate 24, and a partition plate 25. As described later, the casing 20 includes a refrigerant circuit 11, an outer fan 34, and an inner fan 35.

[0051] The outer wall 21 is a plate-like member arranged in a manner covering the open end of the container body 2. The lower portion of the outer wall 21 bulges toward the inner side of the container body 2. The inner wall 22 is a plate-like member extending along the outer wall 21. The inner wall 22 is arranged to cover the surface of the outer wall 21 facing the inner side of the container body 2. The space between the outer wall 21 and the inner wall 22 is filled with a heat insulating material 23.

[0052] The lower portion of the housing 20 is recessed toward the inside of the container body 2. The lower portion of the housing 20 forms an external equipment room 28 that communicates with the external space of the transport container 1. In the external equipment room 28, an external fan 34 is disposed.

[0053] The back panel 24 is a substantially rectangular flat plate-shaped member. The back panel 24 is arranged closer to the inner side of the container body 2 than the inner wall 22, and an in-store air flow path 29 is formed between the back panel 24 and the inner wall 22. The upper end of the in-store air flow path 29 constitutes the suction port 26 of the outer shell 20, and the lower end thereof constitutes the blowing port 27 of the outer shell 20.

[0054] The dividing plate 25 is a plate-shaped component arranged to divide the air flow path 29 in the warehouse into upper and lower parts. The dividing plate 25 is arranged on the upper part of the air flow path 29 in the warehouse. The air flow path 29 in the warehouse is divided by the dividing plate 25 into a primary flow path 29a on the upper side of the dividing plate 25 and a secondary flow path 29b on the lower side of the dividing plate 25. The primary flow path 29a is connected to the storage space 5 via the suction port 26. The secondary flow path 29b is connected to the flow path 4 under the floor via the blowing port 27. An in-warehouse fan 35 is installed on the dividing plate 25. The in-warehouse fan 35 is arranged to blow the air sucked from the primary flow path 29a toward the secondary flow path 29b.

[0055] 〈Refrigerant circuit〉

[0056] like Figure 2 As shown, the refrigerant circuit 11 is a closed circuit formed by connecting the compressor 12, the external heat exchanger 13, the expansion valve 14 and the internal heat exchanger 15 by pipes. When the compressor 12 is operated, the refrigerant circulates in the refrigerant circuit 11 to perform a vapor compression refrigeration cycle. Figure 1 As shown, the external heat exchanger 13 is arranged on the suction side of the external fan 34 in the external equipment room 28, and the internal heat exchanger 15 is arranged in the secondary flow path 29b of the internal air flow path 29. In addition, the compressor 12 is arranged in the external equipment room 28. Figure 1 Illustration omitted.

[0057] - Operation of transport refrigeration equipment -

[0058] The transport refrigeration device 10 performs a cooling operation to cool the air in the transport container 1 .

[0059] In cooling operation, the compressor 12 of the refrigerant circuit 11 operates, and the refrigerant circulates in the refrigerant circuit 11, thereby performing a vapor compression refrigeration cycle. In the refrigerant circuit 11, the refrigerant ejected from the compressor 12 passes through the external heat exchanger 13, the expansion valve 14, and the internal heat exchanger 15 in sequence, and is then sucked into the compressor 12 and compressed by the compressor 12.

[0060] In addition, during 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.

[0061] The flow of the air in the storage room is described below. The air in the storage room existing in the storage space 5 flows into the primary flow path 29a of the storage air flow path 29 through the suction port 26, and is blown out to the secondary flow path 29b by the storage fan 35. The air in the storage room that has flowed into the secondary flow path 29b is cooled when passing through the storage heat exchanger 15, and then blown out from the blowing port 27 to the under-floor flow path 4, and flows into the storage space 5 through the under-floor flow path 4.

[0062] 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 blowing side of the internal fan 35. Therefore, when the internal fan 35 is operating, the air pressure of the secondary flow path 29b is slightly higher than that of the primary flow path 29a.

[0063] - Air conditioning device in the warehouse -

[0064] The transport refrigeration system (10) of the present embodiment includes an in-compartment air conditioning device (100).

[0065] The in-store air conditioner 100 is installed in the transport refrigeration device 10 to perform so-called CA (Controlled Atmosphere) transportation. The in-store air conditioner 100 adjusts the composition of the air in the storage space 5 of the transport container 1 so as to be different from the composition of the atmosphere.

[0066] like Figure 3As shown, the in-store air conditioning device 100 includes a filter unit 220, a main unit 200, a gas supply pipe 275, a gas exhaust pipe 276, a sensor unit 160, a ventilation exhaust pipe 150, and a controller 110. The in-store air conditioning device 100 is a gas separation device of the so-called PSA (Pressure Swing Adsorption) method. The in-store air conditioning device 100 separates the air outside the store (atmosphere) as the air to be processed into a nitrogen-rich gas having a high nitrogen concentration and a low oxygen concentration compared to the atmosphere and an oxygen-rich gas having a low nitrogen concentration and a high oxygen concentration compared to the atmosphere. The nitrogen-rich gas is the first gas, and the oxygen-rich gas is the second gas.

[0067] 〈Filter unit, external air pipe〉

[0068] The filter unit 220 is a box-shaped component. The filter unit 220 is set in the external equipment room 28 of the transport refrigeration device 10. The filter unit 220 includes an air filter 221. The air filter 221 is a filter for capturing dust, salt, etc. contained in the air outside the storage. The air filter 221 of this embodiment is a membrane filter with air permeability and waterproofness.

[0069] The filter unit 220 is connected to the main unit 200 via an external air pipe 241. One end of the external air pipe 241 is connected to the filter unit 220. The other end of the external air pipe 241 is connected to an air pump 231 described later. The external air pipe 241 guides the air outside the storage (atmosphere) that has passed through the air filter 221 to the air pump 231 as processed air.

[0070] 〈Main unit〉

[0071] The main unit 200 is installed in the equipment room 28 outside the transport refrigeration device 10. The main unit 200 includes an air pump 231, a first adsorption cylinder 234, a second adsorption cylinder 235, a first switching valve 232, a second switching valve 233, and a unit casing 201 for storing them. The unit casing 201 stores an inlet pipe 242, a suction pipe 243, a first air pipe 244, and a second air pipe 245.

[0072] <air pump>

[0073] The air pump 231 includes a pressurizing side pump 231a, a decompression side pump 231b, and a driving motor 231c. The pressurizing side pump 231a and the decompression side pump 231b suck air and eject it respectively. The pressurizing side pump 231a and the decompression side pump 231b are both connected to a driving shaft of a driving motor 231c. In the air pump 231, both the pressurizing side pump 231a and the decompression side pump 231b are driven by a driving motor 231c.

[0074] The other end of the external air pipe 241 is connected to the suction port of the pressurizing side pump 231a. One end of the introduction pipe 242 is connected to the discharge port of the pressurizing side pump 231a. The pressurizing side pump 231a supplies the processed air sucked from the external air pipe 241 to the first adsorption cylinder 234 and the second adsorption cylinder 235 via the introduction pipe 242.

[0075] The suction port of the decompression pump 231b is connected to a suction pipe 243. The discharge port of the decompression pump 231b is connected to a first gas pipe 244. The decompression pump 231b discharges gas sucked from the first adsorption cylinder 234 and the second adsorption cylinder 235 through the suction pipe 243 to the first gas pipe 244.

[0076] 〈Introduction pipe〉

[0077] The inlet pipe 242 is a pipe that guides the treated air ejected from the pressurizing side pump 231a to the first adsorption cylinder 234 and the second adsorption cylinder 235. One end of the inlet pipe 242 is connected to the ejection port of the pressurizing side pump 231a. The inlet pipe 242 is branched into two branch pipes at the other end, one branch pipe is connected to the first switching valve 232, and the other branch pipe is connected to the second switching valve 233.

[0078] 〈Suction tube〉

[0079] The suction pipe 243 is a pipe that guides the gas flowing out of the first adsorption cylinder 234 and the second adsorption cylinder 235 to the pressure reducing side pump 231b. One end of the suction pipe 243 is connected to the suction port of the pressure reducing side pump 231b. The suction pipe 243 is branched into two branch pipes at the other end, one branch pipe is connected to the first switching valve 232, and the other branch pipe is connected to the second switching valve 233.

[0080] 〈First trachea〉

[0081] The first gas pipe 244 is a pipe for the nitrogen-rich gas ejected from the pressure-reducing side pump 231b to flow. The first gas pipe 244 constitutes a first gas passage for the nitrogen-rich gas to flow. One end of the first gas pipe 244 is connected to the ejection port of the pressure-reducing side pump 231b. The other end of the first gas pipe 244 is connected to the gas supply pipe 275.

[0082] A check valve 264 is provided on the first gas pipe 244. The check valve 264 only allows gas to flow from one end to the other end of the first gas pipe 244, and blocks gas from flowing in the reverse direction.

[0083] 〈Switch valve〉

[0084] The first switching valve 232 and the second switching valve 233 are switching valves each having three valve ports. The first switching valve 232 and the second switching valve 233 are each configured such that in the first state ( Figure 3 The state represented by the solid line in the figure) and the second state ( Figure 3 The first state is that the first valve port is connected to the second valve port and disconnected from the third valve port, and the second state is that the first valve port is connected to the third valve port and disconnected from the second valve port.

[0085] The first valve port of the first switching valve 232 is connected to one end of the first adsorption cylinder 234. In addition, the first switching valve 232 has a branch pipe of the introduction pipe 242 connected to the second valve port, and a branch pipe of the suction pipe 243 connected to the third valve port. The first switching valve 232 switches the first adsorption cylinder 234 between a state connected to the pressurizing side pump 231a and a state connected to the decompression side pump 231b.

[0086] The first valve port of the second switching valve 233 is connected to one end of the second adsorption cylinder 235. In addition, the second valve port of the second switching valve 233 is connected to a branch pipe of the introduction pipe 242, and the third valve port is connected to a branch pipe of the suction pipe 243. The second switching valve 233 switches the second adsorption cylinder 235 between a state connected to the pressurizing side pump 231a and a state connected to the decompression side pump 231b.

[0087] 〈Adsorption Cylinder〉

[0088] The first adsorption cylinder 234 and the second adsorption cylinder 235 are components including a cylindrical container with both ends closed and an adsorbent filled in the container. The adsorption cylinders 234 and 235 separate the processed air (in this embodiment, the air outside the warehouse) into oxygen-rich gas and nitrogen-rich gas using the adsorbent.

[0089] The adsorbent filled in the adsorption cylinders 234 and 235 has the following properties: in a pressurized state with a pressure higher than the atmospheric pressure, it adsorbs nitrogen and water (water vapor) in the air to be processed, and in a decompressed state with a pressure lower than the atmospheric pressure, it desorbs nitrogen and water. An example of an adsorbent having such a property is porous zeolite, which has micropores with a pore size smaller than the molecular diameter of nitrogen molecules (3.0 angstroms) and larger than the molecular diameter of oxygen molecules (2.8 angstroms).

[0090] Second trachea

[0091] The second gas pipe 245 includes a main pipe 246, a first branch pipe 247a, a second branch pipe 247b, a supply-side branch pipe 248a, and a discharge-side branch pipe 248b. In addition, an oxygen switching valve 249 is provided on the second gas pipe 245. The second gas pipe 245 constitutes a second gas passage through which the oxygen-rich gas flows.

[0092] The first branch pipe 247a is a pipe connecting the other end of the first adsorption cylinder 234 to one end of the main pipe 246. The second branch pipe 247b is a pipe connecting the other end of the second adsorption cylinder 235 to one end of the main pipe 246. A check valve 261 is provided on each of the first branch pipe 247a and the second branch pipe 247b. Each check valve 261 allows air to flow out of the corresponding adsorption cylinder 234, 235 and blocks the reverse flow of air.

[0093] As described above, the first branch pipe 247a and the second branch pipe 247b are connected to one end of the main pipe 246. The other end of the main pipe 246 is connected to the oxygen switching valve 249. The main pipe 246 is provided with a throttle hole 263 and a check valve 262 in sequence from one end to the other end. The check valve 262 allows air to flow from one end of the main pipe 246 to the other end and blocks the reverse flow of air.

[0094] One end of the supply-side branch pipe 248a is connected to the oxygen switching valve 249, and the other end is connected to one end of the gas supply pipe 275. The supply-side branch pipe 248a constitutes a supply passage for introducing the oxygen-rich gas into the interior of the container body 2. One end of the exhaust-side branch pipe 248b is connected to the oxygen switching valve 249, and the other end is connected to one end of the gas exhaust pipe 276. The exhaust-side branch pipe 248b constitutes a discharge passage for discharging the oxygen-rich gas to the outside of the container body 2.

[0095] The oxygen switching valve 249 is a three-way valve. As described above, the main pipe 246, the supply side branch pipe 248a, and the discharge side branch pipe 248b are connected to the oxygen switching valve 249. The oxygen switching valve 249 switches between a first state in which the main pipe 246 is connected to the supply side branch pipe 248a and disconnected from the discharge side branch pipe 248b, and a second state in which the main pipe 246 is connected to the discharge side branch pipe 248b and disconnected from the supply side branch pipe 248a.

[0096] The oxygen switching valve 249 is a switching mechanism that switches the second gas pipe 245 between an introduction state and a discharge state. When the oxygen switching valve 249 is in the first state, the second gas pipe 245 is in the introduction state, and the oxygen-rich gas is introduced into the container body 2 through the supply-side branch pipe 248a. When the oxygen switching valve 249 is in the second state, the second gas pipe 245 is in the discharge state, and the oxygen-rich gas is discharged to the outside of the container body 2 through the discharge-side branch pipe 248b.

[0097] 〈Residual gas exhaust pipe〉

[0098] The first branch pipe 247a and the second branch pipe 247b of the second gas pipe 245 are respectively connected to the residual gas discharge pipe 250. One end of the residual gas discharge 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 residual gas discharge pipe 250 is connected between the first adsorption cylinder 234 and the check valve 261 in the first branch pipe 247a. The other end of the residual gas discharge pipe 250 is connected between the second adsorption cylinder 235 and the check valve 261 in the second branch pipe 247b.

[0099] A residual gas discharge valve 251 is provided on the residual gas discharge pipe 250. The residual gas discharge valve 251 is an on-off valve composed of a solenoid valve. The residual gas discharge valve 251 is opened when the first adsorption cylinder 234 and the second adsorption cylinder 235 are pressure-equalized. In addition, an orifice plate 252 is provided on each side of the residual gas discharge valve 251 on the residual gas discharge pipe 250.

[0100] 〈Exhaust connection pipe〉

[0101] The exhaust connection pipe 271 is connected to the first air pipe 244. One end of the exhaust connection pipe 271 is connected to the first air pipe 244, and the other end is connected to the second air pipe 245. One end of the exhaust connection pipe 271 is connected between the pressure reducing side pump 231b and the check valve 264 in the first air pipe 244. The other end of the exhaust connection pipe 271 is connected to one end of the gas discharge pipe 276.

[0102] A gas discharge valve 272 is provided on the exhaust connection pipe 271. The gas discharge valve 272 is an on-off valve composed of a solenoid valve. When the gas discharge valve 272 is opened, the nitrogen-rich gas flowing through the first gas pipe 244 is discharged to the outside of the container body 2. The gas discharge valve 272 is a flow rate regulating mechanism for regulating the flow rate of the nitrogen-rich gas flowing through the exhaust connection pipe 271. If the opening and closing times of the gas discharge valve 272 are adjusted, the flow rate of the nitrogen-rich gas discharged to the outside of the container body 2 through the exhaust connection pipe 271 changes.

[0103] 〈Gas supply pipe〉

[0104] As described above, the first gas pipe 244 and the supply-side branch pipe 248a of the second gas pipe 245 are connected to one end of the gas supply pipe 275. The gas supply pipe 275 extends to the outside of the unit casing 201. The other end of the gas supply pipe 275 is opened on the downstream side of the in-storage fan 35 in the in-storage air flow path 29 of the transport refrigeration device 10. The gas supply pipe 275 is a pipe for introducing the gas flowing in from one end thereof into the interior of the container body 2.

[0105] The gas supply pipe 275 is provided with a gas supply valve 273. The gas supply valve 273 is an on-off valve constituted by a solenoid valve.

[0106] 〈Gas exhaust pipe〉

[0107] As described above, the exhaust side branch pipe 248b of the second gas pipe 245 and the exhaust connection pipe 271 are connected to one end of the gas exhaust pipe 276. The gas exhaust pipe 276 extends to the outside of the unit casing 201. The other end of the gas exhaust pipe 276 is open to the equipment room 28 outside the transport container 1. The gas exhaust pipe 276 is a pipe for exhausting the gas flowing in from one end thereof to the outside of the container body 2.

[0108] 〈Measurement Pipe〉

[0109] The measuring pipe 281 is connected to the first air pipe 244. The measuring pipe 281 is a pipe for connecting the first air pipe 244 to the sensor unit 160. One end of the measuring pipe 281 is connected to the downstream side of the check valve 264 in the first air pipe 244. The other end of the measuring pipe 281 is connected to the sensor unit 160.

[0110] The measuring pipe 281 is provided with a measuring on-off valve 282. The measuring on-off valve 282 is an on-off valve composed of a solenoid valve. The measuring on-off valve 282 opens when the air flowing through the first air pipe 244 is conveyed to the sensor unit 160.

[0111] 〈Bypass pipe〉

[0112] A bypass connection pipe 255 is connected to the inlet pipe 242. The bypass connection pipe 255 is a pipe for bypassing the first adsorption cylinder 234 and the second adsorption cylinder 235 to supply the air outside the warehouse to the storage space 5 of the transport container 1. One end of the bypass connection pipe 255 is connected between the branching part of the inlet pipe 242 and the pressurizing side pump 231a. The other end of the bypass connection pipe 255 is connected to the downstream side of the check valve 264 in the first air pipe 244.

[0113] The bypass connecting pipe 255 is provided with a bypass opening and closing valve 256. The bypass opening and closing valve 256 is an opening and closing valve composed of a solenoid valve. When the external air discharged from the pressurizing side pump 231a is supplied to the storage space 5 without changing its composition, the bypass opening and closing valve 256 is opened.

[0114] 〈Sensor unit〉

[0115] The sensor unit 160 includes an oxygen sensor 161 , a carbon dioxide sensor 162 , and a sensor housing 163 .

[0116] The oxygen sensor 161 is, for example, a zirconia current sensor that measures the oxygen concentration in a mixed gas such as air. The carbon dioxide sensor 162 is, for example, a non-dispersive infrared (NDIR) sensor that measures the carbon dioxide concentration in a mixed gas such as air. The oxygen sensor 161 and the carbon dioxide sensor 162 are housed in a sensor housing 163.

[0117] The sensor housing 163 is a box-shaped member. The sensor housing 163 includes an air filter 164. The air filter 164 is a membrane filter for capturing dust and the like contained in the air in the storage. The air filter 164 filters the air in the storage that flows into the sensor housing 163.

[0118] The sensor housing 163 is connected to a measuring pipe 281. The sensor housing 163 is also connected to an outlet pipe 165. The outlet pipe 165 has an inlet end connected to the sensor housing 163 and an outlet end opening upstream of the in-compartment fan 35 in the in-compartment air flow path 29.

[0119] When the measuring on-off valve 282 is closed, the air in the storage room flows inside the sensor housing 163. Specifically, the air in the storage room flowing through the air flow path 29 in the storage room flows into the sensor housing 163 through the air filter 164, flows through the sensor housing 163, flows through the outlet pipe 165, and flows into the suction side of the in-storage fan 35 in the air flow path 29 in the storage room. Therefore, when the measuring on-off valve 282 is closed, the oxygen sensor 161 measures the oxygen concentration of the air in the storage room, and the carbon dioxide sensor 162 measures the carbon dioxide concentration of the air in the storage room.

[0120] On the other hand, when the measuring on-off valve 282 is open, the gas flowing in the measuring pipe 281 flows through the interior of the sensor housing 163. Specifically, the gas flowing through the first air pipe 244 or the bypass connecting pipe 255 flows into the sensor housing 163 through the measuring pipe 281, flows through the outlet pipe 165 after passing through the sensor housing 163, and flows into the suction side of the in-cabin fan 35 in the in-cabin air flow path 29. Therefore, when the measuring on-off valve 282 is open, the oxygen sensor 161 measures the oxygen concentration of the gas flowing from the measuring pipe 281 into the sensor housing 163, and the carbon dioxide sensor 162 measures the carbon dioxide concentration of the gas flowing from the measuring pipe 281 into the sensor housing 163.

[0121] 〈Ventilation exhaust pipe〉

[0122] The ventilation exhaust pipe 150 is a pipe for exhausting the air in the transport container 1 to the space outside the container. The ventilation exhaust pipe 150 passes through the outer wall 21 and the inner wall 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 composed of a solenoid valve.

[0123] 〈Controller〉

[0124] like Figure 4 As shown, the controller 110 includes a microcomputer 111 mounted on a control substrate and a storage device 112 storing software for operating the microcomputer 111. The storage device 112 is a semiconductor memory.

[0125] The controller 110 controls the components of the in-store air conditioning device 100. The measured 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 switching valve 136, and the second switching valve 137. In addition, the controller 110 controls the oxygen switching valve 249, the ventilation exhaust valve 151, the excess gas exhaust valve 251, the bypass opening and closing valve 256, the gas exhaust valve 272, the gas supply valve 273, and the measurement opening and closing valve 282.

[0126] - Operation of the air conditioning device in the warehouse -

[0127] The in-store air conditioning device 100 adjusts the composition of the in-store air in the storage space 5 of the transport container 1 (in the present embodiment, the oxygen concentration and the carbon dioxide concentration of the in-store air).

[0128] The air conditioning device 100 in the warehouse performs a lowering operation, a raising operation, and an external air introduction operation. The lowering operation is an operation for lowering the oxygen concentration of the air in the warehouse. The raising operation is an operation for raising the oxygen concentration of the air in the warehouse. The external air introduction operation is an operation for lowering the carbon dioxide concentration of the air in the warehouse.

[0129] In the lowering operation and the raising operation, the air conditioning device 100 in the storage separates the air outside the storage into nitrogen-rich gas (first gas) and oxygen-rich gas (second gas) by repeatedly and alternately performing the first action and the second action. The air conditioning device 100 in the storage repeatedly and alternately performs the first action and the second action for a predetermined switching time (e.g., 14 seconds). The controller 110 controls the first switching valve 232 and the second switching valve 233 so as to alternately perform the first action and the second action.

[0130] 〈First Action〉

[0131] like Figure 5 and Figure 7As shown, in the first action, the first switching valve 232 is set to the first state, and the second switching valve 233 is set to the second state. In addition, in the first action, the excess gas discharge valve 251, the bypass on-off valve 256, and the measuring on-off valve 282 are kept in the closed state. In the first action, the air pump 231 is operated to perform an adsorption action on the first adsorption cylinder 234 and a desorption action on the second adsorption cylinder 235.

[0132] The pressurizing side pump 231a sucks in the air outside the warehouse (atmosphere) from the external air pipe 241 and pressurizes it, and supplies the pressurized air outside the warehouse to the first adsorption cylinder 234. In the first adsorption cylinder 234, nitrogen and water (water vapor) contained in the supplied air outside the warehouse are adsorbed by the adsorbent. As a result, oxygen-rich gas having a lower nitrogen concentration and a higher oxygen concentration than the air outside the warehouse is generated in the first adsorption cylinder 234. The oxygen-rich gas flows out from the first adsorption cylinder 234 to the first branch pipe 247a of the second gas pipe 245.

[0133] On the other hand, the pressure reducing side pump 231b draws gas from the second adsorption cylinder 235. In the second adsorption cylinder 235, the internal pressure is reduced, and nitrogen and water are desorbed from the adsorbent. As a result, nitrogen-rich gas having a high nitrogen concentration and a low oxygen concentration compared to the air outside the warehouse is generated in the second adsorption cylinder 235. The nitrogen-rich gas flows from the second adsorption cylinder 235 into the suction pipe 243 and is sucked into the pressure reducing side pump 231b. The pressure reducing side pump 231b pressurizes the sucked nitrogen-rich gas and ejects it to the first gas pipe 244.

[0134] Second Action

[0135] like Figure 6 and Figure 8 As shown, in the second action, the first switching valve 232 is set to the second state, and the second switching valve 233 is set to the first state. In addition, in the second action, the excess gas discharge valve 251, the bypass on-off valve 256, and the measuring on-off valve 282 are kept in the closed state. Moreover, in the second action, the air pump 231 is operated to perform a desorption action on the first adsorption cylinder 234 and an adsorption action on the second adsorption cylinder 235.

[0136] The pressurizing side pump 231a sucks in the air outside the warehouse (atmosphere) from the external air pipe 241 and pressurizes it, and supplies the pressurized air outside the warehouse to the second adsorption cylinder 235. In the second adsorption cylinder 235, nitrogen and water (water vapor) contained in the supplied air outside the warehouse are adsorbed by the adsorbent. As a result, oxygen-rich gas having a lower nitrogen concentration and a higher oxygen concentration than the air outside the warehouse is generated in the second adsorption cylinder 235. The oxygen-rich gas flows out from the second adsorption cylinder 235 to the second branch pipe 247b of the second gas pipe 245.

[0137] On the other hand, the pressure reducing side pump 231b sucks gas from the first adsorption cylinder 234. In the first adsorption cylinder 234, the internal pressure is reduced, and nitrogen and water are desorbed from the adsorbent. As a result, nitrogen-rich gas having a high nitrogen concentration and a low oxygen concentration compared to the air outside the warehouse is generated in the first adsorption cylinder 234. The nitrogen-rich gas flows from the first adsorption cylinder 234 into the suction pipe 243 and is sucked into the pressure reducing side pump 231b. The pressure reducing side pump 231b pressurizes the sucked nitrogen-rich gas and ejects it into the first gas pipe 244.

[0138] - Reduced operation -

[0139] The lowering operation of the in-compartment air conditioner 100 will be described. In the lowering operation, the in-compartment air conditioner 100 supplies nitrogen-rich gas as the first gas to the storage space 5 to reduce the oxygen concentration of the in-compartment air.

[0140] like Figure 5 and Figure 6 As shown, during the lowering operation, the gas supply valve 273 is kept in an open state, and the gas exhaust valve 272 is kept in a closed state. In addition, during the lowering operation, the oxygen switching valve 249 is set to the second state. As a result, the main pipe 246 is connected to the exhaust side branch pipe 248b, and the second gas pipe 245 is in the exhaust state.

[0141] In the lowering operation, the nitrogen-rich gas ejected from the pressure reducing side pump 231b to the first gas pipe 244 flows into the interior of the container body 2 through the gas supply pipe 275. On the other hand, the oxygen-rich gas that has flowed into the second gas pipe 245 from the first adsorption cylinder 234 or the second adsorption cylinder 235 passes through the main pipe 246 and the discharge side branch pipe 248b in sequence, and then flows out to the outside of the container body 2 through the gas discharge pipe 276.

[0142] During the lowering operation, the ventilation exhaust valve 151 is kept in an open state, and the air in the warehouse flows out to the outside of the container body 2 through the ventilation exhaust pipe 150. Therefore, the air in the warehouse is gradually replaced with nitrogen-enriched gas, and the oxygen concentration of the air in the warehouse gradually decreases. In addition, during the lowering operation, the storage space 5 is kept at a positive pressure by appropriately setting the flow rate of the nitrogen-enriched gas supplied to the storage space 5 and the flow rate of the air in the warehouse discharged from the storage space 5.

[0143] - Elevated operation -

[0144] The following describes the boosting operation of the in-compartment air conditioning apparatus 100. In the boosting operation, the in-compartment air conditioning apparatus 100 supplies oxygen-rich gas as the second gas to the storage space 5 to increase the oxygen concentration of the in-compartment air.

[0145] like Figure 7 and Figure 8As shown, in the raising operation, the gas supply valve 273 is kept in the open state, and the gas exhaust valve 272 is kept in the open state, or is opened and closed. In addition, in the lowering operation, the oxygen switching valve 249 is set to the first state. As a result, the main pipe 246 is connected to the supply side branch pipe 248a, and the second gas pipe 245 is in the introduction state.

[0146] During the raising operation, part of the nitrogen-rich gas ejected from the pressure-reducing side pump 231b to the first gas pipe 244 flows out to the outside of the container body 2 through the exhaust connection pipe 271 and the gas discharge pipe 276 in sequence, and the remaining nitrogen-rich gas flows into the inside of the container body 2 through the gas supply pipe 275. On the other hand, the oxygen-rich gas that has flowed into the second gas pipe 245 from the first adsorption cylinder 234 or the second adsorption cylinder 235 flows into the gas supply pipe 275 after passing through the main pipe 246 and the supply-side branch pipe 248a in sequence, and flows into the inside of the container body 2. In this way, during the lowering operation, part of the nitrogen-rich gas and all of the oxygen-rich gas are supplied to the storage space 5.

[0147] During the lifting operation, the ventilation exhaust valve 151 is kept in an open state, and the air in the warehouse flows out to the outside of the container body 2 through the ventilation exhaust pipe 150. Therefore, the air in the warehouse is gradually replaced with oxygen-rich gas, and the oxygen concentration of the air in the warehouse gradually increases. In addition, during the lifting operation, the storage space 5 is kept at a positive pressure by appropriately setting the flow rate of the oxygen-rich gas and the nitrogen-rich gas supplied to the storage space 5 and the flow rate of the air in the warehouse discharged from the storage space 5.

[0148] 〈Gas flow rate adjustment〉

[0149] In the lifting operation, the air conditioning device 100 in the warehouse adjusts the flow rate of the nitrogen-enriched gas flowing out to the outside of the container body 2 by opening and closing the gas discharge valve 272 as a flow rate adjustment mechanism. When the flow rate of the nitrogen-enriched gas flowing out to the outside of the container body 2 is changed, the flow rate of the nitrogen-enriched gas supplied to the inside of the container body 2 together with the oxygen-enriched gas changes. The air conditioning device 100 in the warehouse adjusts the flow rate of the gas supplied to the inside of the container body 2 in the lifting operation by controlling the gas discharge valve 272.

[0150] As described above, in the in-store air conditioning device 100 in the boost operation, the first action and the second action are alternately switched every predetermined switching time T (T=14 seconds in this embodiment). The in-store air conditioning device 100 opens and closes the gas exhaust valve 272 in the same cycle as the switching cycle of the first action and the second action.

[0151] Specifically, the in-store air conditioning device 100 keeps the gas exhaust valve 272 in a closed state during the closed time Tc, which is a part of the switching time T, and keeps the gas exhaust valve 272 in an open state during the open time To, which is the remaining time of the switching time T. It should be noted that the closed time Tc+open time To=switching time T.

[0152] The in-store air conditioning device 100 adjusts the flow rate of the gas supplied to the inside of the container body 2 during the lifting operation by adjusting the closing time Tc and the opening time To. The longer the closing time Tc is (thus, the shorter the opening time To is), the less the flow rate of the nitrogen-enriched gas flowing out to the outside of the container body 2 is, and the more the flow rate of the gas supplied to the inside of the container body 2 is. In addition, the shorter the closing time Tc is (thus, the longer the opening time To is), the more the flow rate of the nitrogen-enriched gas flowing out to the outside of the container body 2 is, and the less the flow rate of the gas supplied to the inside of the container body 2 is.

[0153] - Operation with external air introduction -

[0154] The external air introduction operation of the indoor air conditioning device 100 will be described. In the external air introduction operation, the indoor air conditioning device 100 directly supplies the outdoor air (atmosphere) to the storage space 5. The external air introduction operation is mainly performed to reduce the carbon dioxide concentration of the indoor air.

[0155] like Fig. 9 As shown, in the external air introduction operation, both the first switching valve 232 and the second switching valve 233 are set to the second state. In addition, in the external air introduction operation, the gas supply valve 273 and the bypass on-off valve 256 are kept in the open state, and the remaining on-off valves 251, 272, and 282 are kept in the closed state. In addition, in the external air introduction operation, the air pump 231 is operated. It should be noted that the oxygen switching valve 249 can be set to either the first state or the second state.

[0156] The pressurizing side pump 231a sucks in the air outside the warehouse (atmosphere) from the external air pipe 241 and pressurizes it, and ejects the pressurized air outside the warehouse to the inlet pipe 242. The air outside the warehouse ejected from the pressurizing side pump 231a flows through the inlet pipe 242, the bypass connecting pipe 255 and the first air pipe 244 in sequence, and is supplied to the in-warehouse air flow path 29. In this way, during the operation of the external air introduction, air with the same composition as the atmosphere is supplied to the storage space 5 of the transport container 1.

[0157] The pressure reducing pump 231b sucks gas from both the first adsorption cylinder 234 and the second adsorption cylinder 235, and discharges the sucked gas to the first air pipe 244. The gas discharged from the pressure reducing pump 231b to the first air pipe 244 is supplied to the air flow path 29 inside the warehouse together with the outside air that has flowed into the first air pipe 244 from the bypass connecting pipe 255.

[0158] When the pressure reducing side pump 231b sucks gas from the first adsorption cylinder 234 and the second adsorption cylinder 235, the pressure of the first adsorption cylinder 234 and the second adsorption cylinder 235 gradually decreases. Moreover, when the duration of the external gas introduction operation exceeds a certain period of time (for example, 45 seconds), the flow rate of the gas sucked by the pressure reducing side pump 231b is substantially zero.

[0159] During the operation of introducing external air, the ventilation exhaust valve 151 is kept in an open state, and the air in the warehouse flows out to the outside of the container body through the ventilation exhaust pipe 150. Therefore, the air in the warehouse is gradually replaced by the atmosphere, and the carbon dioxide concentration of the air in the warehouse gradually decreases. In addition, during the operation of introducing external air, the storage space 5 is kept at a positive pressure by appropriately setting the flow rate of the external air supplied to the storage space 5 and the flow rate of the internal air discharged from the storage space 5.

[0160] - Operation switching of the air conditioning device in the warehouse -

[0161] As described above, the air conditioner 100 performs the lowering operation, the raising operation, and the outside air introduction operation. In addition, the air conditioner 100 performs the standby operation for monitoring the oxygen concentration and carbon dioxide concentration of the air in the warehouse while stopping the lowering operation, the raising operation, and the outside air introduction operation.

[0162] Fresh food stored in the storage space 5 breathes by taking in oxygen and releasing carbon dioxide. Therefore, during the standby operation, the amount of oxygen contained in the air in the storage gradually decreases. Therefore, the air conditioning device 100 in the storage performs a boost operation to replenish the oxygen reduced by the breathing of the fresh food.

[0163] Here, refer to Fig.10 The flowchart of FIG. 1 is used to explain the operation of the controller 110 of the air conditioning device 100 in the storage room to control the start and stop of the boost operation. The controller repeats the operation in units of a predetermined time (for example, 10 minutes). Fig.10 The actions are shown in the flowchart.

[0164] Fig.10The control action shown is an action for maintaining the measurement value Co of the oxygen sensor 161 (the actual measured value of the oxygen concentration of the air in the storage) within the target range. The target range is a numerical range including the set value Cs of the oxygen concentration of the air in the storage. The target range of this embodiment is the range of Cs±α (that is, the range of Cs-α or more and Cs+α or less). The value of α is, for example, 0.5%.

[0165] In the process of step ST1 , the controller 110 acquires the measurement value Co of the oxygen sensor 161 .

[0166] In the next step ST2, the controller 110 determines whether the condition "the measured value Co of the oxygen sensor 161 is lower than the lower limit value Cs-α) of the target range" is satisfied. If the condition is satisfied, the controller 110 performs the process of step ST3; if the condition is not satisfied, the controller 110 performs the process of step ST4.

[0167] In the process of step ST3, the controller 110 starts the boost operation of the indoor air conditioning apparatus 100. When starting the boost operation, the controller 110 switches the oxygen switching valve 249 from the second state to the first state.

[0168] In the process of step ST4, the controller 110 determines whether the condition that "the measurement value Co of the oxygen sensor 161 is higher than the upper limit value Cs+α) of the target range is satisfied." If this condition is satisfied, the controller 110 performs the process of step ST5.

[0169] In the process of step ST5, the controller 110 stops the boost operation of the indoor air conditioning apparatus 100. When stopping the boost operation, the controller 110 switches the oxygen switching valve 249 from the first state to the second state.

[0170] If the condition of step ST4 is not satisfied, the measured value Co of the oxygen sensor 161 is within the target range (that is, the relationship of Cs-α≤Co≤Cs+α is satisfied). Therefore, in this case, the controller 110 ends Fig.10 The control action of the flowchart maintains the operating state of the air conditioning device 100 in the warehouse.

[0171] - Features of the embodiment (1) -

[0172] The air conditioning device 100 in the warehouse of this embodiment performs a lowering operation to reduce the oxygen concentration of the air in the warehouse and an increasing operation to increase the oxygen concentration of the air in the warehouse. In the increasing operation, oxygen-rich gas having a lower nitrogen concentration and a higher oxygen concentration than the air outside the warehouse is introduced into the interior of the container body 2 through the second gas passage 245. Therefore, compared with the case where the air outside the warehouse is introduced into the interior of the container body 2 in order to increase the oxygen concentration of the air in the warehouse, the increasing speed of the oxygen concentration of the air in the warehouse becomes faster. As a result, the time required to increase the oxygen concentration of the air in the warehouse is shortened.

[0173] - Features of the embodiment (2) -

[0174] In the in-store air conditioning device 100 of the present embodiment, the second gas pipe 245 constituting the second gas passage is switched between an introduction state and a discharge state by operating the oxygen switching valve 249 as a switching mechanism. In the second gas pipe 245 in the introduction state, the oxygen switching valve 249 connects the main pipe 246 with the supply side branch pipe 248a, and the oxygen-rich gas is introduced into the interior of the container body 2 through the supply side branch pipe 248a. In the second gas pipe 245 in the discharge state, the oxygen switching valve 249 connects the main pipe 246 with the discharge side branch pipe 248b, and the oxygen-rich gas is discharged to the outside of the container body 2 through the discharge side branch pipe 248b.

[0175] - Features of the embodiment (3) -

[0176] In the air conditioning device 100 in the present embodiment, the controller 110 controls the oxygen switching valve 249 according to the measured value of the oxygen sensor 161, thereby starting or stopping the boost operation. When the air conditioning device 100 in the storage room starts the boost operation, the second air pipe 245 switches from the discharge state to the introduction state. When the air conditioning device 100 in the storage room stops the boost operation, the second air pipe 245 switches from the introduction state to the discharge state.

[0177] - Features of the embodiment (4) -

[0178] The in-compartment air conditioning apparatus 100 of the present embodiment supplies all of the oxygen-rich gas flowing out of the adsorption columns 234 , 235 and a portion of the nitrogen-rich gas flowing out of the adsorption columns 234 , 235 to the interior of the container body 2 during the ascending operation.

[0179] As described above, the adsorbent included in the adsorption cylinders 234 and 235 adsorbs nitrogen and water (water vapor). In the adsorption cylinders 234 and 235 that are the objects of the adsorption action, the nitrogen and water vapor contained in the air outside the warehouse as the processed air are adsorbed by the adsorbent. Therefore, the humidity of the oxygen-rich gas flowing out of the adsorption cylinders 234 and 235 that are the objects of the adsorption action is low (that is, the amount of water vapor contained is small). In the lifting operation, when only the oxygen-rich gas with low humidity is supplied to the interior of the container body 2, the humidity of the storage space 5 is reduced, which may cause the freshness of fresh food to decrease.

[0180] On the other hand, the nitrogen-enriched gas flowing out from the adsorption cylinders 234 and 235 that are the subject of the desorption operation contains water vapor desorbed from the adsorbent, and therefore has a high humidity. Therefore, in order to suppress the decrease in humidity of the air in the warehouse during the boost operation, the in-warehouse air conditioning device 100 of this embodiment supplies the nitrogen-enriched gas with a high humidity together with the oxygen-enriched gas with a low humidity to the interior of the container body 2.

[0181] As described above, according to the in-compartment air conditioning apparatus 100 of the present embodiment, it is possible to suppress a decrease in humidity of the in-compartment air during the raising operation and to shorten the time required for the composition of the in-compartment air to reach the target composition.

[0182] - Features of the embodiment (5) -

[0183] The air conditioning device 100 in the storage room of the present embodiment adjusts the flow rate of the gas supplied to the storage space 5 during the lifting operation by opening and closing the gas discharge valve 272 during the lifting operation. Therefore, the air conditioning device 100 in the storage room of the present embodiment can adjust the flow rate of the first gas introduced into the interior of the storage room 2 in order to suppress the decrease in humidity of the air in the storage room during the lifting operation. Therefore, according to the present embodiment, the decrease in humidity of the air in the storage room can be suppressed, and the time required for the composition of the air in the storage room to reach the target composition can be shortened.

[0184] As described above, during the lifting operation, the mixed gas of the oxygen-rich gas and the nitrogen-rich gas flows into the interior of the container body 2, and the air in the container flows out to the outside of the container body 2 through the ventilation exhaust pipe 150. At this time, since the air pressure of the storage space 5 is kept substantially constant, the greater the flow rate of the gas flowing into the interior of the container body 2, the greater the flow rate of the air in the container flowing out to the outside of the container body 2.

[0185] During the lifting operation, the carbon dioxide concentration of the gas supplied to the interior of the container body 2 is as low as that of the air outside the container. Therefore, when the flow rate of the gas supplied to the interior of the container body 2 is large, the amount of carbon dioxide flowing out of the container body 2 increases, which may cause the carbon dioxide concentration of the air inside the container to decrease.

[0186] In contrast, the in-store air conditioning device 100 of this embodiment can adjust the flow rate of gas supplied to the storage space 5 during the boost operation. Therefore, according to this embodiment, by adjusting the flow rate of gas supplied to the storage space 5 during the boost operation, the decrease in the carbon dioxide concentration of the in-store air during the boost operation can be suppressed.

[0187] - Modification of the embodiment -

[0188] The in-store air conditioning apparatus 100 of the above-mentioned embodiment may also be applied to the following modified examples. It should be noted that the following modified examples may be appropriately combined or replaced as long as the function of the in-store air conditioning apparatus 100 is not impaired.

[0189] <First Modification>

[0190] In the indoor air conditioning apparatus 100 of the above embodiment, the oxygen switching valve 249 which is a three-way valve constitutes the switching mechanism, but the switching mechanism is not limited to the three-way valve.

[0191] For example, a solenoid valve provided on each of the supply-side branch pipe 248a and the discharge-side branch pipe 248b may constitute the switching mechanism. In this case, when the solenoid valve of the supply-side branch pipe 248a is in an open state and the solenoid valve of the discharge-side branch pipe 248b is in a closed state, the second air pipe 245 is in an introduction state. In this case, when the solenoid valve of the supply-side branch pipe 248a is in a closed state and the solenoid valve of the discharge-side branch pipe 248b is in an open state, the second air pipe 245 is in a discharge state.

[0192] <Second Modification>

[0193] In the in-store air conditioning device 100 of the above-mentioned embodiment, a solenoid valve is used as the gas discharge valve 272 constituting the flow rate regulating mechanism, but the gas discharge valve 272 is not limited to a solenoid valve. For example, the gas discharge valve 272 may also be an electric valve with a variable opening. In this case, the controller 110 of the in-store air conditioning device 100 adjusts the flow rate of the gas supplied to the inside of the container body 2 during the lifting operation by adjusting the opening of the gas discharge valve 272 constituted by the electric valve.

[0194] <Third Modification>

[0195] The air conditioning device 100 in the above embodiment can also be installed in a fixed refrigerator or freezer. In addition, the air conditioning device 100 in the above embodiments can also be installed in a land-based refrigerated or frozen container transported by truck or railway. In addition, the air conditioning device 100 in the above embodiment can also be installed in a refrigerated or frozen truck in which the box body forming the cargo hold and the chassis are integrated.

[0196] The above describes the implementation and variations, but it should be understood that various changes can be made to the scheme and specific methods without departing from the subject and scope of the claims. In addition, as long as the function of the object of the present disclosure is not affected, the above implementation and variations can be appropriately combined or replaced. In addition, the words "first", "second", etc. in the specification and claims are only used to distinguish the sentences containing the above words, and are not intended to limit the number and order of the sentences.

[0197] - Industrial Applicability -

[0198] In summary, the present invention is useful for in-store air conditioning devices, refrigeration devices, and transport containers.

[0199] - Explanation of symbols -

[0200] 1Transport container

[0201] 2Container body (storage warehouse)

[0202] 10 Transport refrigeration equipment (refrigeration equipment)

[0203] 11 Refrigerant circuit

[0204] 100 Air conditioning device in warehouse

[0205] 110 Controller

[0206] 161 oxygen sensor

[0207] 234 first adsorption cylinder (first adsorber, adsorber)

[0208] 235 second adsorption cylinder (second adsorber, adsorber)

[0209] 244 first gas pipe (first gas passage)

[0210] 245 second gas pipe (second gas passage)

[0211] 246 Trunk access (Trunk access)

[0212] 248a Supply side branch pipe (supply passage)

[0213] 248b discharge side branch pipe (discharge passage)

[0214] 249 oxygen switching valve (switching mechanism)

[0215] 271 Exhaust connection pipe (first gas exhaust passage)

[0216] 272 Gas discharge valve (flow regulating mechanism)

Claims

1. An in-store air conditioning device (100) for adjusting the composition of in-store air inside a storage store (2), characterized in that: The invention comprises an adsorber (234, 235), a first gas passage (244) and a second gas passage (245), The adsorber (234, 235) has an adsorbent for adsorbing nitrogen and water vapor, and separates the external air outside the storage room into a first gas having a higher nitrogen concentration and humidity and a lower oxygen concentration than the external air, and a second gas having a lower nitrogen concentration and humidity and a higher oxygen concentration than the external air. The first gas flowing out of the adsorber (234, 235) flows in the first gas passage (244), The second gas flowing out of the adsorber (234, 235) flows in the second gas passage (245), The air conditioning device (100) in the warehouse performs lowering operation and raising operation. The reducing operation is an operation for introducing the first gas into the interior of the storage (2) via the first gas passage (244) to reduce the oxygen concentration of the air in the storage. The raising operation is an operation for introducing the second gas into the interior of the storage (2) via the second gas passage (245) to raise the oxygen concentration of the air in the storage. During the lifting operation, the second gas is introduced into the interior of the storage (2) via the second gas passage (245), and a portion of the first gas is introduced into the interior of the storage (2) via the first gas passage (244).

2. The in-store air conditioning device (100) according to claim 1, characterized in that: The second gas passage (245) can be switched between an introduction state in which the second gas is introduced into the interior of the storage container (2) and a discharge state in which the second gas is discharged to the outside of the storage container (2).

3. The in-store air conditioning device (100) according to claim 2, characterized in that: The second gas passage (245) includes a trunk passage (246), a supply passage (248a), a discharge passage (248b) and a switching mechanism (249). The main passage (246) is connected to the adsorbers (234, 235), The supply passage (248a) is connected to the interior of the storage chamber (2). The discharge passage (248b) is connected to the outside of the storage chamber (2). In the introduction state, the switching mechanism (249) connects the main passage (246) with the supply passage (248a); in the discharge state, the switching mechanism (249) connects the main passage (246) with the discharge passage (248b).

4. The in-store air conditioning device (100) according to claim 2 or 3, characterized in that: The in-store air conditioning device (100) includes an oxygen sensor (161) and a controller (110). The oxygen sensor (161) measures the oxygen concentration of the air in the storage. The controller (110) switches the second gas passage (245) between the introduction state and the discharge state according to the measurement value of the oxygen sensor (161).

5. The in-store air conditioning device (100) according to any one of claims 1 to 3, characterized in that: The in-store air conditioning device (100) includes a flow rate regulating mechanism (272) for regulating the flow rate of the first gas introduced into the interior of the storage store (2) during the lifting operation.

6. The in-store air conditioning device (100) according to claim 5, characterized in that: The in-store air conditioning device (100) comprises a first gas exhaust passage (271), one end of which is connected to the first gas passage (244), and the other end of which is connected to the outside of the storage room (2). The flow rate adjustment mechanism (272) is a valve provided in the first gas exhaust passage (271).

7. The in-store air conditioning device (100) according to any one of claims 1 to 3, characterized in that: The adsorber includes a first adsorber (234) and a second adsorber (235) each having the adsorbent, The in-store air conditioning device (100) repeatedly and alternately performs a first action and a second action, wherein the first action is to supply the air outside the store to the first adsorber (234), to make the second gas flow out of the first adsorber (234), and to make the first gas flow out of the second adsorber (235), The second operation is an operation of supplying the external air to the second adsorber (235), causing the second gas to flow out of the second adsorber (235), and causing the first gas to flow out of the first adsorber (234).

8. A refrigeration device, characterized in that: The invention comprises an in-store air conditioning device (100) as claimed in any one of claims 1 to 7 and a refrigerant circuit (11) for performing a refrigeration cycle to adjust the temperature of the in-store air.

9. A transport container, characterized in that: It comprises the refrigeration device (10) as claimed in claim 8 and a container body, the refrigeration device (10) is installed on the container body, and the storage (2) is constituted by the container body.

Images