Refrigeration container

Abstract

Provided is a refrigeration container comprising a container body that has therein a refrigeration space which is to be cooled and a refrigerator that is capable of cooling a circulated gas which is taken in from the refrigeration space. The refrigerator includes: an inlet line that guides the circulated gas from the refrigeration space to a compressor; a compressed gas line that guides, to a turbine, compressed gas which is the circulated gas compressed by the compressor; an outlet line that guides, to the refrigeration space, circulated gas which has been expanded by the turbine; a heat exchanger that exchanges heat between the circulated gas which flows through the inlet line and the compressed gas which flows through the compressed gas line; a warming line that extracts circulated gas from the compressed gas line upstream of the heat exchanger and guides the circulated gas to the inlet line upstream of the heat exchanger; and a warming-line-side flow rate adjustment valve that is capable of adjusting the flow rate of the compressed gas which flows through the warming line.

Description

Refrigerated Container

[0001] The present disclosure relates to a refrigerated container. The present application claims priority based on Japanese Patent Application No. 2025-049556 filed with the Japan Patent Office on March 25, 2025, the content of which is incorporated herein by reference.

[0002] A refrigerated container is a container provided with a refrigeration function for freezing or refrigerating articles such as cargo stored in the interior of the container. Patent Document 1 discloses a refrigerated container including: a container body having a refrigeration space, which is an object to be cooled, inside thereof; and a refrigerator configured to be capable of cooling circulating gas sucked from the refrigeration space.

[0003] Japanese Unexamined Patent Publication No. 2024-055257

[0004] Incidentally, frost may adhere to the refrigerator during operation of the refrigerator. When frost adheres to the refrigerator, the flow of circulating gas in the refrigerator is impaired, so it is desirable to provide a defrost function to melt the frost adhering to the refrigerator. When a refrigerator is equipped with a defrost function, there is a risk that this leads to complication of the structure of the refrigerator. In a refrigerated container, since the interior space is limited, it is desirable that the structure of the refrigerator is simple even when the refrigerator is equipped with a defrost function.

[0005] In view of the above circumstances, an object of at least one embodiment of the present disclosure is to provide a refrigerated container capable of defrosting a gas flow path through which circulating gas sucked from the refrigeration space of a refrigerator flows, while suppressing complication of the configuration of the refrigerator.

[0006] A refrigerated container according to at least one embodiment of the present disclosure comprises a container body having a refrigerated space to be cooled inside, and a refrigerator configured to cool a circulating gas drawn in from the refrigerated space, wherein the refrigerator includes: a compressor configured to compress the circulating gas; a turbine configured to expand the circulating gas; an inlet line for leading the circulating gas from the refrigerated space to the compressor; a compressed gas line for leading the compressed gas, which is the circulating gas compressed by the compressor, to the turbine; an outlet line for leading the circulating gas, which has been expanded by the turbine, to the refrigerated space; a heat exchanger configured to perform heat exchange between the circulating gas flowing through the inlet line and the compressed gas flowing through the compressed gas line; a warm air line for drawing out the circulating gas from the side of the compressed gas line upstream of the heat exchanger and leading it to the side of the inlet line upstream of the heat exchanger; and a warm air line side flow control valve provided in the warm air line and configured to adjust the flow rate of the compressed gas flowing through the warm air line.

[0007] According to at least one embodiment of the present disclosure, a refrigerated container is provided that can defrost the gas flow path through which circulating gas drawn in from the refrigerated space of a refrigerator flows, while suppressing the complexity of the refrigerator's configuration.

[0008] This is a schematic diagram showing a refrigerated container according to one embodiment of the present disclosure. This is a schematic diagram showing a refrigerated container according to one embodiment of the present disclosure. This is a schematic diagram showing a refrigerated container according to one embodiment of the present disclosure. This is a schematic perspective view of a refrigerated container according to one embodiment of the present disclosure. This is a schematic cross-sectional view along the longitudinal direction of the container body of a refrigerated container according to one embodiment of the present disclosure. This is a schematic diagram of the refrigeration casing of a refrigerated container according to one embodiment of the present disclosure, viewed from the direction indicated by arrow A in Figure 4. This is a schematic diagram of the refrigeration casing of a refrigerated container according to one embodiment of the present disclosure, viewed from the direction indicated by arrow A in Figure 4. This is an explanatory diagram for illustrating the entrance box of a refrigerated container according to one embodiment of the present disclosure.

[0009] Hereinafter, several embodiments of this disclosure will be described with reference to the attached drawings. However, the dimensions, materials, shapes, relative arrangements, etc., of the components described or shown in the drawings as embodiments are not intended to limit the scope of this disclosure, but are merely illustrative examples.

[0010] (Refrigerated Container) Figures 1 to 3 are schematic diagrams showing a refrigerated container 1 according to one embodiment of the present disclosure. As shown in Figures 1 to 3, a refrigerated container 1 according to several embodiments comprises a container body 2 having a refrigerated space 20 to be cooled inside, and a refrigerator 3 configured to cool circulating gas drawn in from the refrigerated space 20.

[0011] The refrigerated space 20 can accommodate goods such as cargo. The refrigerator 3 is configured to cool gases such as air present in the refrigerated space 20. The refrigerated space 20 is cooled by drawing in circulating gas from the refrigerated space 20, cooling it, and then returning it to the refrigerated space 20. The refrigerated container 1 can adjust the temperature of the gas inside the container (the gas present in the refrigerated space 20) using the refrigerator 3. In the following embodiment, the refrigerator 3 can set the temperature of the gas inside the container to an extremely low temperature (below -40°C and above -120°C, preferably below -80°C).

[0012] (Refrigeration Unit) The refrigerator unit 3, as shown in Figures 1 to 3, includes a compressor 41 configured to compress the circulating gas, a turbine 42 configured to expand the circulating gas, an inlet line 5, a compressed gas line 6, an outlet line 7, a heat exchanger 8, a warm air line 11, and a warm air line side flow control valve 12.

[0013] (Inlet line, compressed gas line, outlet line) The inlet line 5 is a flow path for guiding circulating gas from the refrigerated space 20 to the compressor 41, as shown in Figures 1 to 3. The compressed gas line 6 is a flow path for guiding the compressed gas, which is the circulating gas compressed by the compressor 41, to the turbine 42, as shown in Figures 1 to 3. The outlet line 7 is a flow path for guiding the circulating gas, which has been expanded by the turbine 42, back to the refrigerated space 20.

[0014] As shown in Figures 1 to 3, the inlet line 5 is provided in the refrigeration space 20 and has a suction port 51 (opening) for drawing circulating gas from the refrigeration space 20 into the interior of the inlet line 5. The suction port 51 is formed at the upstream end of the inlet line 5. The downstream end of the inlet line 5 is connected to the compressor 41.

[0015] The compressed gas line 6 is located outside the refrigeration space 20. The upstream end of the compressed gas line 6 is connected to the compressor 41, and the downstream end is connected to the turbine 42.

[0016] As shown in Figures 1 to 3, the outlet line 7 is provided in the refrigeration space 20 and has an outlet 71 (opening) for guiding circulating gas from inside the outlet line 7 into the refrigeration space 20. The outlet 71 is formed at the downstream end of the outlet line 7. The upstream end of the outlet line 7 is connected to the turbine 42.

[0017] (Turbomachinery) In the illustrated embodiment, the refrigerator 3 described above includes a turbomachinery 4, as shown in Figures 1 to 3. The turbomachinery 4 includes the compressor 41 described above, the turbine 42 described above, a rotating shaft 43, and an electric motor 44, as shown in Figure 1. The rotating shaft 43 is connected to the compressor 41 and the turbine 42. The electric motor 44 is configured to generate rotational force to rotate the compressor 41, the turbine 42, and the rotating shaft 43.

[0018] In the illustrated embodiment, the impeller of the compressor 41 is attached to one side of the rotating shaft 43, and the wheel (turbine wheel) of the turbine 42 is attached to the other side of the rotating shaft 43. In other words, the compressor 41 and the turbine 42 are arranged coaxially with each other via the rotating shaft 43, which is the output shaft of the electric motor 44, and are connected to the rotating shaft 43. The electric motor 44 is configured to transmit the rotational force it generates to the rotating shaft 43.

[0019] In the illustrated embodiment, the electric motor 44 is supplied with current from a power source such as a generator (not shown), and is driven by the current supplied from the power source to drive (rotate) the rotating shaft 43, the compressor 41, and the turbine 42.

[0020] By driving the compressor 41, the gas in the refrigerated space 20 is drawn into the inlet line 5 via the suction port 51 and guided to the compressor 41. The compressor 41 is configured to compress the circulating gas, which is the gas drawn in from the refrigerated space 20 via the suction port 51. The circulating gas compressed by the compressor 41 is heated and pressurized higher than before it was introduced into the compressor 41, becoming a gas of relatively high temperature and pressure.

[0021] The compressed gas, which is a circulating gas compressed by the compressor 41, is led to the turbine 42 via the compressed gas line 6. The turbine 42 is configured to expand the compressed gas that has been led to it. The circulating gas expanded by the turbine 42 is cooled and depressurized compared to before it was introduced into the turbine 42, becoming a relatively cold and low-pressure fluid. The circulating gas expanded in the turbine 42 is blown out into the refrigerated space 20 from the outlet line 7 via the outlet 71.

[0022] (Heat Exchanger) The heat exchanger 8 is configured to exchange heat between the circulating gas flowing through the inlet line 5 and the compressed gas flowing through the compressed gas line 6. The heat exchanger 8 is configured so that heat is transferred between two gases with different temperatures separated by a heat transfer wall. Through heat transfer in the heat exchanger 8, the compressed gas flowing through the compressed gas line 6 is cooled and the circulating gas flowing through the inlet line 5 is heated. The circulating gas heated by the heat exchanger 8 is introduced into the compressor 41. The compressed gas cooled by the heat exchanger 8 is introduced into the turbine 42.

[0023] (Cooler) In the illustrated embodiment, the refrigerator 3 described above further includes a cooler 9 configured to cool the compressed gas flowing upstream of the heat exchanger 8 (compressor 41 side) of the compressed gas line 6. The cooler 9 is configured to exchange heat between the compressed gas flowing upstream of the heat exchanger 8 of the compressed gas line 6 and a coolant (for example, water) that is colder than the compressed gas. The cooler 9 is configured so that two fluids with different temperatures (compressed gas and coolant) transfer heat across a heat transfer wall.

[0024] Heat transfer in the cooler 9 cools the compressed gas flowing upstream of the heat exchanger 8 in the compressed gas line 6. The compressed gas cooled by the cooler 9 is then introduced into the heat exchanger 8 through the compressed gas line 6.

[0025] In the illustrated embodiment, the refrigerator 3 includes a coolant line 91 for circulating coolant and a cooling device 92 for cooling the coolant flowing through the coolant line 91. The coolant line 91 is a passage for returning the coolant taken from the cooler 9 to the cooler 9. The coolant line 91 is provided with a coolant pump 93 for supplying coolant in the coolant line 91 and a radiator 94. The cooling device 92 includes a radiator 94 and a fan 95 for air-cooling the radiator 94.

[0026] The coolant, which has been heated by heat transfer in the cooler 9, is guided to the coolant line 91 by the coolant pump 93, cooled by the cooling system 92 including the radiator 94, and then guided back to the cooler 9.

[0027] (Warm air line) As shown in Figures 1 to 3, the warm air line 11 is a flow path that extracts circulating gas from the upstream side of the heat exchanger 8 of the compressed gas line 6 (compressor 41 side) and guides it to the upstream side of the heat exchanger 8 of the inlet line 5 (suction port 51 side). In the embodiment shown in Figure 1, the upstream end 111 of the warm air line 11 is connected to the upstream side of the heat exchanger 8 of the compressed gas line 6 (compressor 41 side). The downstream end 112 of the warm air line 11 is connected to the upstream side of the heat exchanger 8 of the inlet line 5 (suction port 51 side).

[0028] In the illustrated embodiment, the upstream end 111 of the warm air line 11 is connected upstream of the cooler 9 of the compressed gas line 6. In this case, by connecting the upstream end 111 of the warm air line 11 upstream of the cooler 9 of the compressed gas line 6, the refrigerated container 1 can circulate high-temperature circulating gas (warm air) in the warm air line 11 compared to when it is connected between the cooler 9 and the heat exchanger 8 of the compressed gas line 6, thereby promoting defrosting of the chiller 3 by the warm air. In some other embodiments, the upstream end 111 of the warm air line 11 may be connected between the cooler 9 and the heat exchanger 8 of the compressed gas line 6.

[0029] (Warm air line side flow control valve) The warm air line side flow control valve 12 is installed in the warm air line 11 and is configured to adjust the flow rate of compressed gas flowing through the warm air line 11. The warm air line side flow control valve 12 is configured to adjust the flow rate of circulating gas that is led downstream of the warm air line side flow control valve 12 (to the inlet line 5 side) via the warm air line side flow control valve 12 by changing the opening degree of the valve body located in the warm air line 11. The warm air line side flow control valve 12 may be an on / off valve whose opening degree can be adjusted to fully closed and fully open, or it may be an opening degree control valve whose opening degree can be adjusted to fully closed, fully open and at least one intermediate opening degree between these.

[0030] (Opening and closing of valves during normal operation) During normal operation (steady-state operation) of the chiller 3, the warm air line side flow control valve 12 provided in the warm air line 11 is closed. During normal operation (steady-state operation) of the chiller 3, the circulating gas flows through the inlet line 5, the compressed gas line 6, and the outlet line 7 without passing through the warm air line 11.

[0031] (Opening and closing of valves during defrost operation) During the defrost operation of the chiller 3 to melt frost accumulated on the chiller 3, the warm air line side flow control valve 12, which is provided in the warm air line 11, is opened. During the defrost operation of the chiller 3, warm air (circulating gas) that has become relatively high temperature and pressure by being compressed by the compressor 41 passes through the warm air line 11 and is guided upstream of the heat exchanger 8 in the inlet line 5. As a result, the warm air heats the inlet line 5 and the low-temperature side of the heat exchanger 8 provided in the inlet line 5, and melts the frost accumulated on the inlet line 5 and the low-temperature side of the heat exchanger 8 provided in the inlet line 5.

[0032] By warming the inlet line 5 and the low-temperature side of the heat exchanger 8 installed in the inlet line 5 with warm air, cooling of the high-temperature side of the heat exchanger 8 installed in the compressed gas line 6 by the low-temperature side is suppressed.

[0033] Warm air that has passed through the warm air line 11 and been guided upstream of the heat exchanger 8 in the inlet line 5 is drawn in by the compressor 41 and passes through the inlet line 5, the compressed gas line 6, the heat exchanger 8 installed in the compressed gas line 6, the turbine 42, and the outlet line 7, thereby warming the entire gas flow path through which the circulating gas of the chiller 3 flows, and melting the frost that has accumulated throughout the gas flow path of the chiller 3.

[0034] In this embodiment, the refrigerated container 1 can melt frost attached to the entire gas flow path of the chiller 3 by increasing the flow rate of warm air (circulating gas) flowing through the warm air line 11 using the warm air line side flow control valve 12. In this embodiment, the refrigerated container 1 allows defrosting of the chiller 3 using the relatively simple structure of the warm air line 11 and the warm air line side flow control valve 12, thus suppressing the complexity of the chiller 3's configuration.

[0035] In some embodiments of the refrigerated container 1, as shown in Figures 2 and 3, the warm air line 11 described above includes a bypass line 13 and connecting lines 14 (14A, 14B). The warm air line side flow control valve 12 described above includes a bypass line side flow control valve 15 and connecting line side flow control valves 16 (16A, 16B). The chiller 3 described above includes a compressed gas line side flow control valve 17.

[0036] (Bypass Line) The bypass line 13 is a flow path for extracting circulating gas from upstream of the heat exchanger 8 of the compressed gas line 6 and guiding it downstream of the heat exchanger 8 of the compressed gas line 6. In the illustrated embodiment, the upstream end 131 of the bypass line 13 is connected upstream of the cooler 9 of the compressed gas line 6. The downstream end 132 of the bypass line 13 is connected downstream of the heat exchanger 8 of the compressed gas line 6. In some other embodiments, the upstream end 131 of the bypass line 13 may be connected between the cooler 9 and the heat exchanger 8 of the compressed gas line 6.

[0037] (Bypass line side flow control valve) The bypass line side flow control valve 15 is installed in the bypass line 13 and is configured to adjust the flow rate of the circulating gas flowing through the bypass line 13. The bypass line side flow control valve 15 is configured to adjust the flow rate of the circulating gas that is led downstream of the bypass line side flow control valve 15 (towards the turbine 42) via the bypass line 13 by changing the opening degree of the valve body located in the bypass line 13. The bypass line side flow control valve 15 may be an on / off valve whose opening degree can be adjusted to fully closed and fully open, or it may be an opening degree control valve whose opening degree can be adjusted to fully closed, fully open and at least one intermediate opening degree between these.

[0038] (Connection Line) The connection line 14 is a flow path for guiding the warm air (circulating gas) extracted into the bypass line 13 to the upstream side of the heat exchanger 8 in the inlet line 5. The upstream end 141 of the connection line 14 is connected to either the downstream side of the heat exchanger 8 in the compressed gas line 6 or to the bypass line 13, and the downstream end 142 is connected to the upstream side of the heat exchanger 8 in the inlet line 5.

[0039] In the embodiment shown in Figure 2, the upstream end 141 of the connection line 14 (14A) is connected to the bypass line 13. The refrigerated container 1 shown in Figure 2 is effective in defrosting the inlet line 5 and the heat exchanger 8 because, by connecting the upstream end 141 of the connection line 14 (14A) to the bypass line 13, the warm air guided to the bypass line 13 can be directly guided upstream of the heat exchanger 8 of the inlet line 5 via the connection line 14 (14A).

[0040] In the embodiment shown in Figure 3, the upstream end 141 of the connection line 14 (14B) is connected downstream of the heat exchanger 8 of the compressed gas line 6. In the refrigerated container 1 shown in Figure 3, by connecting the upstream end 141 of the connection line 14 (14B) downstream of the heat exchanger 8 of the compressed gas line 6, through which relatively low-temperature gas flows during the normal operation of the refrigerator 3, the heat input through the connection line 14 (14B) during the normal operation of the refrigerator 3 is suppressed, thereby suppressing a decrease in the performance of the refrigerator 3.

[0041] (Flow rate control valve on the connection line side) The flow rate control valve 16 on the connection line side is configured to adjust the flow rate of the circulating gas flowing through the connection line 14. In the embodiment shown in Figure 2, the flow rate control valve 15 on the bypass line side is provided downstream of the connection point between the bypass line 13 and the upstream end 141 of the connection line 14 (14A). The flow rate control valve 16 (16A) on the connection line is provided on the connection line 14. In addition, in some other embodiments of the refrigerated container 1, a three-way valve integrating the bypass line side flow rate control valve 15 and the flow rate control valve 16 (16A) may be provided at the connection point between the bypass line 13 and the upstream end 141 of the connection line 14 (14A).

[0042] In the embodiment shown in Figure 3, the flow control valve 16 (16B) on the connection line side is provided on the connection line 14 (14B).

[0043] (Compressed Gas Line Side Flow Control Valve) The compressed gas line side flow control valve 17 is configured to adjust the flow rate of compressed gas flowing downstream of the connection point with the upstream end 131 of the bypass line 13 in the compressed gas line 6, and upstream of the connection point with the downstream end 132 of the bypass line 13. In the embodiments shown in Figures 2 and 3, the compressed gas line side flow control valve 17 is provided between the connection point with the upstream end 131 of the bypass line 13 in the compressed gas line 6 and the heat exchanger 8.

[0044] The refrigerated container 1 according to the present embodiment enables local defrosting operation of the refrigerator 3 that melts frost on devices constituting the refrigerator 3 (e.g., the turbine 42 and the heat exchanger 8) by opening and closing the bypass line-side flow rate adjustment valve 15, the connection line-side flow rate adjustment valve 16 (16A, 16B), and the compressed gas line-side flow rate adjustment valve 17, and warm-up operation for heating the refrigerated space 20 to a temperature higher than the air temperature outside the container body 2. The refrigerated container 1 can suppress freezing of the object to be frozen stored in the refrigerated space 20 by performing the warm-up operation for heating the refrigerated space 20 to a temperature higher than the air temperature outside the container body 2.

[0045] In the embodiment shown in FIG. 2 and FIG. 3, during normal operation of the refrigerator 3, the compressed gas line-side flow rate adjustment valve 17 is open, and the bypass line-side flow rate adjustment valve 15 and the connection line-side flow rate adjustment valve 16 are closed.

[0046] In the embodiment shown in FIG. 2 and FIG. 3, during defrosting operation on the turbine 42 side of the refrigerator 3, the bypass line-side flow rate adjustment valve 15 and the compressed gas line-side flow rate adjustment valve 17 are open, and the connection line-side flow rate adjustment valve 16 is closed. In this case, warm air (circulating gas) is guided to the turbine 42 and the outlet line 7 via the bypass line 13, and the frost adhering to the turbine 42 and the outlet line 7 is melted by the warm air.

[0047] In the embodiment shown in FIG. 2, during defrosting operation on the heat exchanger 8 side of the refrigerator 3, the connection line-side flow rate adjustment valve 16 and the compressed gas line-side flow rate adjustment valve 17 are open, and the bypass line-side flow rate adjustment valve 15 is closed. In the embodiment shown in FIG. 3, during defrosting operation on the heat exchanger 8 side of the refrigerator 3, the bypass line-side flow rate adjustment valve 15, the connection line-side flow rate adjustment valve 16, and the compressed gas line-side flow rate adjustment valve 17 are open. In these cases, warm air (circulating gas) is guided to the inlet line 5 and the heat exchanger 8 via the connection line 14, and the frost adhering to the inlet line 5 and the heat exchanger 8 is melted by the warm air.

[0048] In the embodiment shown in Figures 2 and 3, during the warm-up operation of the refrigerator 3, the bypass line-side flow rate adjustment valve 15 is open, and the connection line-side flow rate adjustment valve 16 and the compressed gas line-side flow rate adjustment valve 17 are closed. In these cases, warm air (circulating gas) is guided to the freezing space 20 via the bypass line 13, the turbine 42 and the outlet line 7, and the freezing space 20 can be warmed by the warm air.

[0049] In the refrigeration container 1 according to some embodiments, as shown in Figures 2 and 3, the refrigerator 3 described above includes the above-described electric motor 44 configured to generate rotational force for rotating the compressor 41, and a rotation speed control device 45 for controlling the rotation speed of the electric motor 44. In the illustrated embodiment, the rotation speed control device 45 includes an inverter that can increase or decrease the rotation speed of the electric motor 44 by changing the frequency of the power supplied to the electric motor 44.

[0050] When the refrigerator 3 starts defrosting operation or warm-up operation, at least one of the following is performed: opening the bypass line-side flow rate adjustment valve 15, opening the connection line-side flow rate adjustment valve 16, or closing the compressed gas line-side flow rate adjustment valve 17. The rotation speed control device 45 is configured to reduce the rotation speed of the electric motor 44 when at least one condition is satisfied: opening either the bypass line-side flow rate adjustment valve 15 or the connection line-side flow rate adjustment valve 16, or closing the compressed gas line-side flow rate adjustment valve 17. The rotation speed control device 45 is configured to reduce the rotation speed of the electric motor 44 below the rotation speed during normal operation (steady operation) when the above condition is satisfied. Note that the rotation speed control device 45 may adjust the rotation speed of the electric motor 44 to a rotation speed preset for each open / closed state of each of the bypass line-side flow rate adjustment valve 15, the connection line-side flow rate adjustment valve 16, and the compressed gas line-side flow rate adjustment valve 17.

[0051] During defrosting and warming operations of the refrigerator 3, relatively high-temperature warm air (circulating gas) extracted from upstream of the heat exchanger 8 of the compressed gas line 6 is introduced into the components and flow paths of the refrigerator 3. In this embodiment, the refrigerated container 1 reduces the rotational speed of the electric motor 44 using the rotational speed control device 45 during defrosting and warming operations of the refrigerator 3, thereby suppressing excessive heat buildup of the warm air (circulating gas) and preventing heat damage to the components and flow paths of the refrigerator 3. By suppressing heat damage to the components and flow paths of the refrigerator 3, the refrigerated container 1 can improve the reliability of the components and flow paths of the refrigerator 3.

[0052] Figure 4 is a schematic perspective view of a refrigerated container 1 according to one embodiment of the present disclosure. Figure 5 is a schematic cross-sectional view of the container body 2 of the refrigerated container 1 according to one embodiment of the present disclosure, along its longitudinal direction. Figures 6 and 7 are schematic views of the refrigeration casing 100 of the refrigerated container 1 according to one embodiment of the present disclosure, viewed from the direction indicated by arrow A in Figure 4.

[0053] (Container body) As shown in Figure 4, the container body 2 has a plurality of walls 21 to 24 and is formed in a rectangular cylindrical shape that extends along the longitudinal direction of the container body 2. Hereinafter, the horizontal direction perpendicular to the longitudinal direction of the container body 2 is defined as the width direction of the container body 2. The plurality of walls 21 to 24 include a ceiling wall 21 that extends along a direction perpendicular to the height direction of the container body 2, a bottom wall 22 that extends below the ceiling wall 21 along a direction perpendicular to the height direction of the container body 2, and a pair of long side walls 23, 24 that are spaced apart from each other and each connects the ceiling wall 21 and the bottom wall 22.

[0054] The container body 2 may be a shipping container used for transporting goods, etc. The container body 2 may be a standard shipping container such as a 10ft container, a 20ft container, or a 40ft container.

[0055] As shown in Figures 4 to 7, the refrigerated container 1 comprises the container body 2 described above, the refrigeration unit 3 described above, the refrigeration unit casing 100, and the inlet box 300.

[0056] (Refrigeration Casing) The refrigeration casing 100 is located inside the container body 2 and has a refrigeration housing space 101 inside in which the refrigeration unit 3 is housed. In the illustrated embodiment, as shown in Figure 5, the refrigeration casing 100 is located in an opening formed on one side in the longitudinal direction of the container body 2. The refrigerated container 1 is equipped with a door 25 that is configured to be openable and closable and located in an opening formed on the other side in the longitudinal direction of the container body 2. By opening the door 25, goods such as cargo and people can be moved between the outside of the container body 2 and the refrigerated space 20.

[0057] In the illustrated embodiment, the refrigeration casing 100 includes a back plate portion 102, a top plate portion 103, a bottom plate portion 104, and a pair of side plate portions 105 and 106, as shown in Figure 4. Each of the back plate portion 102, the top plate portion 103, the bottom plate portion 104, and the pair of side plate portions 105 and 106 is formed in a flat plate shape. The back plate portion 102 extends along a direction perpendicular to the longitudinal direction of the container body 2, on the side of the refrigerated space 20 in the longitudinal direction of the container body 2, relative to the refrigeration unit 3.

[0058] The ceiling plate portion 103 extends from the upper end of the back plate portion 102 along a direction perpendicular to the height direction of the container body 2, and covers the top of the refrigeration unit 3. The outer wall surface of the ceiling plate portion 103 faces the inner surface of the ceiling wall 21 with a gap in between. The bottom plate portion 104 extends from the lower end of the back plate portion 102 along a direction perpendicular to the height direction of the container body 2, and covers the bottom of the refrigeration unit 3. The outer wall surface of the bottom plate portion 104 faces the inner surface of the bottom wall 22 (floor surface 221) with a gap in between.

[0059] Each of the pair of side panels 105 and 106 extends along a direction perpendicular to the width direction of the container body 2, covering the side of the refrigeration unit 3. Side panel 105 is connected to one end of each of the back panel 102, top panel 103, and bottom panel 104 in the width direction of the container body 2. The outer wall surface of side panel 105 faces the inner surface of the long side wall 23 with a gap in between. Side panel 106 is connected to the other end of each of the back panel 102, top panel 103, and bottom panel 104 in the width direction of the container body 2. The outer wall surface of side panel 106 faces the inner surface of the long side wall 24 with a gap in between.

[0060] (Thermal insulation) In the illustrated embodiment, the refrigerated container 1 includes thermal insulation 200 laminated on the outer wall surface of the refrigeration unit casing 100, as shown in Figures 4 and 5. The thermal insulation 200 includes a rear-side thermal insulation 202, an upper-side thermal insulation 203, a lower-side thermal insulation 204, and a pair of side-side thermal insulation 205 and 206. The thermal insulation 200 allows the refrigerated container 1 to suppress heat input to the refrigeration unit housing space 101 and heat dissipation from the refrigeration unit housing space 101.

[0061] The rear insulation material 202 is laminated on the outer wall surface (the side facing the freezing space 20) of the back plate portion 102. The top insulation material 203 is laminated on the outer wall surface (top surface) of the ceiling plate portion 103. The bottom insulation material 204 is laminated on the outer wall surface (bottom surface) of the bottom plate portion 104. The side insulation material 205 is laminated on the outer wall surface of the side plate portion 105, and the side insulation material 206 is laminated on the outer wall surface of the side plate portion 106.

[0062] (Inlet Box) The inlet box 300 constitutes part of the inlet line 5, which is a flow path for guiding circulating gas from the refrigeration space 20 to the refrigerator 3. The inlet box 300 protrudes from the back plate portion 102 of the refrigerator casing 100 toward the refrigerator housing space 101 and has an internal box space 301 which is an internal space connected to the refrigeration space 20.

[0063] As shown in Figures 4 to 7, the entrance box 300 includes a front panel 302, a bottom panel 303, a first side panel 304, and a second side panel 305. Each of the front panel 302, bottom panel 303, first side panel 304, and second side panel 305 is formed in a flat shape.

[0064] The front panel 302 extends in a direction perpendicular to the longitudinal direction of the container body 2, on the side of the refrigeration unit housing space 101 in the longitudinal direction of the container body 2, compared to the back panel 102. The front panel 302 faces the back panel 102 across the box interior space 301.

[0065] The bottom plate 303 extends below the ceiling plate portion 103, along a direction perpendicular to the height direction of the container body 2. The bottom plate 303 faces the ceiling plate portion 103 across the box interior space 301.

[0066] Each of the first side plate 304 and the second side plate 305 extends along a direction perpendicular to the width direction of the container body 2. The first side plate 304 is connected to one end of each of the front plate 302 and bottom plate 303 in the width direction of the container body 2. The outer wall surface of the first side plate 304 faces the inner surface of the side plate portion 105 in the width direction of the container body 2 with a gap in between.

[0067] The second side plate 305 is connected to the other end of the front plate 302 and the bottom plate 303 in the width direction of the container body 2. In the illustrated embodiment, the second side plate 305 is formed integrally with the side plate portion 105, but it may be formed separately from the side plate portion 105.

[0068] As shown in Figure 5, the refrigeration casing 100 has an inlet-side communication hole 52 for guiding circulating gas from the outside of the refrigeration casing 100 into the box interior space 301, and an outlet-side communication hole 72 for guiding circulating gas from the refrigeration housing space 101 to the outside of the refrigeration casing 100. In the illustrated embodiment, the inlet-side communication hole 52 is a through-hole that penetrates the ceiling plate portion 103. The outlet-side communication hole 72 is a through-hole that penetrates the back plate portion 102.

[0069] The freezing space 20 of the container body 2 is provided with the aforementioned intake port 51 (opening) for drawing in air or other gases from within the freezing space 20, and the aforementioned outlet port 71 (opening) for blowing air or other gases into the freezing space 20. In the illustrated embodiment, the intake port 51 is located above the inlet side communication hole 52. The outlet port 71 is located below the outlet side communication hole 72.

[0070] (Inlet passage) In the illustrated embodiment, an inlet passage 601 is formed inside the container body 2 to connect the box interior space 301 and the refrigeration space 20, and to guide the gas present in the refrigeration space 20 to the box interior space 301 via the intake port 51. The inlet passage 601 is provided outside the refrigeration casing 100 and constitutes part of the inlet line 5. An intake port 51 is formed at one end of the inlet passage 601, and the other end of the inlet passage 601 is connected to the inlet side communication hole 52.

[0071] The circulating gas drawn in from the refrigeration space 20 through the suction port 51 flows through the inlet channel 601 and is then guided into the box interior space 301 through the inlet side communication hole 52.

[0072] (Outlet passage) In the illustrated embodiment, an outlet passage 701 is formed inside the container body 2 to connect the refrigeration unit housing space 101 and the refrigeration space 20, and to guide the circulating gas cooled in the refrigeration unit 3 to the refrigeration space 20 via the outlet 71. The outlet passage 701 is provided outside the refrigeration unit casing 100 and constitutes part of the outlet line 7. An outlet 71 is formed at one end of the outlet passage 701, and the other end of the outlet passage 701 is connected to the outlet side communication hole 72.

[0073] The circulating gas expanded by the turbine 42 is guided to the outlet passage 701 via the outlet communication hole 72, flows through the outlet passage 701, and is then blown out into the refrigerated space 20 from the outlet 71.

[0074] The compressor 41, turbine 42, electric motor 44, heat exchanger 8, cooler 9, and cooling device 92 are housed in the chiller housing space 101, as shown in Figures 6 and 7. The heat exchanger 8 is located above the chiller housing space 101, and the cooler 9 and cooling device 92 are located below the chiller housing space 101. The compressor 41, turbine 42, and electric motor 44 are located below the heat exchanger 8 and above the cooler 9 and cooling device 92 in the chiller housing space 101.

[0075] The bypass line side flow control valve 15, the connecting line side flow control valve 16, and the compressed gas line side flow control valve 17 are housed in the chiller housing space 101, as shown in Figures 6 and 7. The bypass line side flow control valve 15, the connecting line side flow control valve 16, and the compressed gas line side flow control valve 17 are positioned below the heat exchanger 8 and above the cooler 9 and cooling device 92 in the chiller housing space 101.

[0076] The heat exchanger 8 is positioned in the width direction of the container body 2 between one of the pair of side plate portions 105 and 106, specifically between one side plate portion 105 and the first side plate 304 of the entrance box 300.

[0077] The refrigeration casing 100 includes a mounting section 107 on which the heat exchanger 8 is mounted. The mounting section 107 extends below the ceiling plate section 103 and along a direction perpendicular to the height direction of the container body 2. The upper surface of the mounting section 107 faces the inner surface of the ceiling plate section 103, with the space in which the heat exchanger 8 is arranged in between. The mounting section 107 is supported by at least one of the back plate section 102 or the side plate section 105.

[0078] The heat exchanger 8 has an intake section 81 for taking in circulating gas, and the intake section 81 is connected to the first side plate 304 of the inlet box 300. The first side plate 304 has a connection port 306 to which the intake section 81 of the heat exchanger 8 is connected. By connecting the intake section 81 to the first side plate 304 of the inlet box 300, circulating gas is drawn from the box interior space 301 to the heat exchanger 8 via the connection port 306.

[0079] In this embodiment, the refrigerated container 1 can be made more compact by arranging the entrance box 300 inside the refrigeration unit casing 100, thereby utilizing the internal space of the container body 2. The refrigerated container 1 can utilize the internal space of the refrigeration unit casing 100 by arranging the heat exchanger 8, which has a relatively large volume in the refrigeration unit 3, between the side plate portion 105 and the first side plate 304 of the entrance box 300, and placing it on the mounting portion 107.

[0080] In this embodiment, the refrigerated container 1 has the intake section 81 of the heat exchanger 8 connected to the inlet box 300, which allows the heat exchanger 8 to be supported by the inlet box 300. This improves the reliability of the refrigeration unit 3 against vibrations that occur when transporting the refrigerated container 1.

[0081] In some embodiments of the refrigerated container 1, the intake section 81 of the heat exchanger 8 extends linearly along the width direction of the container body 2 and is connected to the connection port 306. In this embodiment of the refrigerated container 1, the length and surface area of ​​the intake section 81 of the heat exchanger 8 can be reduced, which allows for a more compact refrigerator 3 and suppresses heat input from outside the intake section 81 to the circulating gas flowing through the intake section 81.

[0082] In some embodiments of the refrigerated container 1, as shown in Figures 6 and 7, the connection line 14 is connected to the inlet box 300 (bottom plate 303 in the illustrated example). The inlet box 300 (bottom plate 303 in the illustrated example) has warm-air side connection ports 307A and 307B to which the connection line 14 is connected. By connecting the connection line 14 to the inlet box 300, circulating gas can be guided from the connection line 14 to the box interior space 301 via the warm-air side connection ports 307A and 307B. The connection line 14 may also be connected to a location other than the bottom plate 303 of the inlet box 300.

[0083] In this embodiment, the refrigerated container 1 has a connection line 14 connected to the entrance box 300, which allows the connection line 14 to be supported by the entrance box 300. This improves the reliability of the refrigeration unit 3 against vibrations that occur when transporting the refrigerated container 1.

[0084] (Drain Discharge Hole) Figure 8 is an explanatory diagram illustrating the inlet box 300 of a refrigerated container 1 according to one embodiment of the present disclosure. In some embodiments of the refrigerated container 1, as shown in Figure 8, the inlet box 300 described above includes at least a first side plate 304 having a connection port 306 formed therein, and a second side plate 305 having a drain discharge hole 308 formed below the connection port 306.

[0085] Frost that accumulates in the internal space 301 of the box may melt due to normal operation or defrosting of the refrigerator 3, or natural melting after operation of the refrigerator 3, generating drain. In this embodiment, the refrigerated container 1 has a drain discharge hole 308 formed in the second side plate 305, allowing drain to be discharged from the internal space 301 of the box to the outside of the inlet box 300 through the drain discharge hole 308.

[0086] (Inclined plate) In some embodiments of the refrigerated container 1, as shown in Figure 8, the above-described inlet box 300 includes a first side plate 304 having a connection port 306, a second side plate 305 having a drain discharge hole 308, and an inclined plate 309. One end of the inclined plate 309 is connected below the connection port 306 of the first side plate 304, and the other end is connected below the drain discharge hole 308 of the second side plate 305. The inclined plate 309 is inclined downward in the width direction of the container body 2 as it approaches the second side plate 305.

[0087] In this embodiment, the refrigerated container 1 can guide the drain present in the box interior space 301 to the second side plate 305, where the drain discharge hole 308 is formed, by the inclination of the inclined plate 309, thereby improving the drain discharge performance of the inlet box 300. In the illustrated embodiment, the inclined plate 309 is separate from the bottom plate 303 and is positioned above the bottom plate 303 in the box interior space 301, but the inclined plate 309 may be a bottom plate 303 that has been inclined.

[0088] (Inlet channel forming section) In some embodiments of the refrigerated container 1, an inlet channel forming section 600 is provided which forms an inlet channel 601 above the internal space 301 of the box. In the embodiment shown in Figure 5, the inlet channel forming section 600 is positioned above the ceiling plate section 103 and forms the inlet channel 601 between itself and the ceiling plate section 103. The inlet channel forming section 600 includes an upper plate 602 that defines the area above the inlet channel 601, a front plate 603 that defines the side of the inlet channel 601 that is separated from the refrigerated space 20, and a back plate 604 that defines the side of the inlet channel 601 that is separated from the refrigerated space 20.

[0089] The upper plate 602 extends above the ceiling plate portion 103, along a direction perpendicular to the height direction of the container body 2. The front plate 603 is connected to the end of the upper plate 602 on the side of the refrigeration unit housing space 101 in the longitudinal direction of the container body 2, and extends along a direction perpendicular to the longitudinal direction of the container body 2. The back plate 604 is connected to the end of the upper plate 602 on the side of the refrigeration space 20 in the longitudinal direction of the container body 2, and extends along a direction perpendicular to the longitudinal direction of the container body 2.

[0090] In the embodiment shown in Figure 5, the suction port 51 described above includes a first suction port 51A, which is a through-hole that penetrates the top plate 602, and a second suction port 51B, which is a through-hole that penetrates the back plate 604. The suction port 51 may also include only one of the first suction port 51A or the second suction port 51B. In the illustrated example, the first suction port 51A and the second suction port 51B are rectangular holes with a longitudinal direction along the width direction of the container body 2.

[0091] In the embodiment shown in Figure 5, the refrigerated container 1 includes a first suction port filter 401 provided at the first suction port 51A and having a mesh opening smaller than the size of the first suction port 51A, and a second suction port filter 402 provided at the second suction port 51B and having a mesh opening smaller than the size of the second suction port 51B. The first suction port filter 401 and the second suction port filter 402 can suppress the entry of foreign matter into the inlet line 5.

[0092] In the illustrated embodiment, the refrigerated container 1 includes a back plate portion 102 of the refrigeration casing 100, which comprises a first back plate portion 102A and second back plate portions 102B and 102C that are lower than the first back plate portion 102A and protrude further toward the refrigeration housing space 101 than the first back plate portion 102A. The outlet side communication hole 72 is formed in the second back plate portions 102B and 102C.

[0093] In the embodiment shown in Figure 5, the first back plate portion 102A extends along a direction perpendicular to the longitudinal direction of the container body 2. The second back plate portions 102B and 102C include an inclined portion 102B, one end of which is connected to the lower end of the first back plate portion 102A, and which is inclined to be located downward from the one end toward the other end that protrudes toward the refrigeration unit housing space 101 in the longitudinal direction of the container body 2, and a flat plate portion 102C that extends downward from the other end of the inclined portion 102B along a direction perpendicular to the longitudinal direction of the container body 2.

[0094] In this embodiment, the refrigerated container 1 allows for the utilization of the internal space of the container body 2 and enables the refrigerated container 1 to be made more compact by having a part of the back plate portion 102 of the refrigeration unit casing 100 (second back plate portions 102B, 102C) protrude towards the refrigeration unit housing space 101.

[0095] In the illustrated embodiment, the outlet line 7 includes turbine outlet piping 73 connecting the turbine 42 and the outlet side communication hole 72. The outlet side communication hole 72 is formed in the second back plate portions 102B and 102C (in the illustrated example, the inclined portion 102B).

[0096] In this embodiment, the refrigerated container 1 has an outlet-side communication hole 72 formed in the second back plate portion 102B, 102C (inclined portion 102B in the illustrated example) that protrudes toward the refrigerator housing space 101 side of the back plate portion 102. This reduces the length and surface area of ​​the turbine outlet piping 73 that connects the turbine 42 and the outlet-side communication hole 72, thereby suppressing heat input from outside the turbine outlet piping 73 to the circulating gas flowing through the turbine outlet piping 73.

[0097] Furthermore, in this embodiment, the refrigerated container 1 has an outlet-side communication hole 72 formed in the inclined portion 102B, so that the outlet-side communication hole 72 faces downwards towards the refrigerated space 20 in the longitudinal direction of the container body 2. In this case, the circulating gas blown out from the outlet-side communication hole 72 flows toward the outlet 71, so that the pressure loss of the circulating gas flowing through the outlet passage 701 can be suppressed.

[0098] (Outlet channel forming section) In some embodiments of the refrigerated container 1, as shown in Figure 5, an outlet channel forming section 700 is provided between the refrigerator housing space 101 and the refrigerated space 20 in the longitudinal direction of the container body 2, forming an outlet channel 701.

[0099] The outlet channel forming section 700 is supported by the refrigerator casing 100 (first back plate section 102A in the illustrated example) and hangs down below the first back plate section 102A, forming an outlet channel 701 between it and the second back plate sections 102B and 102C. As shown in Figure 5, the outlet channel forming section 700 may be laminated on the side of the back insulation material 202 laminated on the outer wall surface of the first back plate section 102A that is facing the refrigeration space 20, and the outlet channel 701 may be formed between it and the back insulation material 202 laminated on the outer wall surfaces of the second back plate sections 102B and 102C. In this case, the outlet channel forming section 700 can support the back insulation material 202 laminated on the outer wall surface of the first back plate section 102A, and deformation of the back insulation material 202 laminated on the outer wall surface of the first back plate section 102A can be suppressed.

[0100] In the illustrated embodiment, the outlet channel forming section 700 is a metal plate extending along a direction perpendicular to the longitudinal direction of the container body 2. By using a metal with a smaller heat capacity than the rear-side insulating material 202 for the outlet channel forming section 700, the time required to cool the refrigerated space 20 can be shortened.

[0101] The air outlet 71 is formed between the lower end of the outlet flow path forming section 700 and the floor surface (floor surface 221 of the bottom wall 22) of the refrigerated space 20 of the container body 2. In the illustrated example, the air outlet 71 is a rectangular hole with a longitudinal direction along the width direction of the container body 2.

[0102] In this embodiment, the refrigerated container 1 has an outlet channel forming section 700 that forms an outlet channel 701 on the side of the refrigeration space 20 that is closer to the refrigeration unit casing 100 in the longitudinal direction of the container body 2, thereby suppressing heat input to the circulating gas flowing through the outlet channel 701. Furthermore, the outlet channel forming section 700 prevents damage or deterioration of the rear insulation material 202 due to collisions with cargo during unloading or cleaning of the interior of the container, thereby reducing its functionality. In addition, in this embodiment, the refrigerated container 1 has both the function of supporting the rear insulation material 202 and the function of forming the outlet channel 701 in the outlet channel forming section 700, which allows for the utilization of the internal space of the container body 2 and enables the refrigerated container 1 to be made more compact.

[0103] (Laying Member) In some embodiments of the refrigerated container 1, as shown in Figure 5, a laying member 800 may be provided which is laid on the floor surface (floor surface 221 of the bottom wall 22) of the refrigerated space 20 of the container body 2. A load to be cooled (object to be cooled) can be placed on the upper surface 801 of the laying member 800. The laying member 800 is configured to form a gas flow path 802 that extends along the longitudinal direction of the container body 2 between the upper surface 801 and the floor surface 221 of the bottom wall 22. The above-mentioned outlet 71 is formed below the upper surface 801 of the laying member 800 and is configured to communicate with the gas flow path 802. Specifically, the outlet 71 is formed at a height position such that at least a portion of it overlaps with the gas flow path 802 in the height direction of the container body 2.

[0104] In this embodiment, the refrigerated container 1 is configured such that the circulating gas (cold air) introduced into the gas flow path 802 via the outlet 71 flows through the gas flow path 802 and then flows above the upper surface 801 of the laying member 800. In this case, the circulating gas (cold air) introduced into the refrigerated space 20 via the outlet 71 can be guided to a wide area of ​​the refrigerated space 20. Therefore, even if the cargo to be cooled is placed on the upper surface 801 of the laying member 800, the entire refrigerated space 20 can be effectively cooled.

[0105] In this specification, expressions describing relative or absolute arrangements such as "in a certain direction," "along a certain direction," "parallel," "orthogonal," "center," "concentric," or "coaxial" shall not only describe such arrangements strictly, but also describe states of relative displacement with tolerances or angles or distances sufficient to achieve the same function. For example, expressions describing things being in an equal state such as "identical," "equal," and "homogeneous" shall not only describe states of being strictly equal, but also describe states where tolerances or differences exist to the extent that the same function is achieved. Furthermore, in this specification, expressions describing shapes such as quadrilaterals or cylindrical shapes shall not only describe geometrically precise quadrilaterals or cylindrical shapes, but also describe shapes including concave and concave parts, chamfered parts, etc., to the extent that the same effect is achieved. In addition, in this specification, expressions such as "equipment," "includes," or "possesses" a component are not exclusive expressions that exclude the existence of other components.

[0106] This disclosure is not limited to the embodiments described above, but also includes modified forms of the embodiments described above, as well as forms that combine these forms as appropriate.

[0107] The contents described in some of the embodiments above can be understood, for example, as follows:

[0108] [1] A refrigerated container (1) according to at least one embodiment of the present disclosure comprises a container body (2) having a refrigerated space (20) to be cooled inside, and a refrigerator (3) configured to cool a circulating gas drawn in from the refrigerated space (20), wherein the refrigerator (3) comprises a compressor (41) configured to compress the circulating gas, a turbine (42) configured to expand the circulating gas, an inlet line (5) for leading the circulating gas from the refrigerated space (20) to the compressor (41), a compressed gas line (6) for leading the compressed gas, which is the circulating gas compressed by the compressor (41), to the turbine (42), an outlet line (7) for leading the circulating gas, which has been expanded by the turbine (42), to the refrigerated space, and a heat exchanger (8) configured to perform heat exchange between the circulating gas flowing through the inlet line (5) and the compressed gas flowing through the compressed gas line (6). The system includes a warm air line (11) for extracting the circulating gas from the compressed gas line (6) upstream of the heat exchanger (8) and guiding it to the inlet line (5) upstream of the heat exchanger (8), and a warm air line side flow control valve (12) provided in the warm air line (11) and configured to adjust the flow rate of the compressed gas flowing through the warm air line (11).

[0109] According to the configuration described in [1] above, the refrigerated container (1) can melt frost attached to the entire gas flow path of the chiller (3) by increasing the flow rate of warm air (circulating gas) flowing through the warm air line (11) using the warm air line side flow control valve (12). In this embodiment, the refrigerated container (1) can defrost the chiller (3) using the relatively simple warm air line (11) and warm air line side flow control valve (12), thus suppressing the complexity of the chiller (3) configuration.

[0110] [2] In some embodiments, the refrigerated container (1) described in [1] above, the warm air line (11) includes: a bypass line (13) for extracting the circulating gas from the compressed gas line (6) upstream of the heat exchanger (8) and guiding it to the compressed gas line (6) downstream of the heat exchanger (8); and a connecting line (14) whose upstream end (141) is connected to either the compressed gas line (6) downstream of the heat exchanger (8) or the bypass line (13), and whose downstream end is connected to the inlet line (5) upstream of the heat exchanger (8); the warm air line side flow control valve (12) includes: a bypass line side flow control valve (15) configured to adjust the flow rate of the circulating gas flowing through the bypass line (13); and a connecting line side flow control valve (16) configured to adjust the flow rate of the circulating gas flowing through the connecting line (14); and the refrigerator (3) is The system further includes a compressed gas line side flow control valve (17) configured to adjust the flow rate of the compressed gas flowing downstream of the connection point with the upstream end (131) of the bypass line (13) in the compressed gas line (6), and upstream of the connection point with the downstream end (132) of the bypass line (13).

[0111] According to the configuration described in [2] above, the refrigerated container (1) can perform localized defrosting of the chiller (3) to melt frost on the components constituting the chiller (3) (for example, the turbine 42 and the heat exchanger 8), and warm-up operation to heat the chilled space (20) to a temperature higher than the ambient temperature outside the container body (2) by opening and closing the bypass line side flow control valve (15), the connection line side flow control valve (16), and the compressed gas line side flow control valve (17).

[0112] [3] In some embodiments, the refrigerated container (1) described in [2] above, wherein the upstream end (141) of the connection line (14) is connected to the bypass line (13).

[0113] According to the configuration described in [3] above, the refrigerated container (1) connects the upstream end (141) of the connection line (14) to the bypass line (13), thereby directly guiding the warm air introduced into the bypass line (13) to the upstream side of the heat exchanger (8) of the inlet line (5) via the connection line (14), which is effective for defrosting the inlet line (5) and the heat exchanger (8).

[0114] [4] In some embodiments, the refrigerated container (1) described in [2] above, wherein the upstream end (141) of the connection line (14) is connected downstream of the heat exchanger (8) of the compressed gas line (6).

[0115] According to the configuration described in [4] above, the refrigerated container (1) connects the upstream end (141) of the connection line (14) downstream of the heat exchanger (8) of the compressed gas line (6), through which relatively low-temperature gas flows during the normal operation of the chiller (3). This suppresses the heat input through the connection line (14) during the normal operation of the chiller (3), thereby preventing a decrease in the performance of the chiller (3).

[0116] [5] In some embodiments, a refrigerated container (1) according to any of [2] to [4] above, wherein the refrigerator (3) includes an electric motor (44) configured to generate a rotational force to rotate the compressor (41), and a rotational speed control device (45) for controlling the rotational speed of the electric motor (44), wherein the rotational speed control device (45) is configured to reduce the rotational speed of the electric motor (44) when either the bypass line side flow control valve (15) or the connection line side flow control valve (16) is opened, or when the compressed gas line side flow control valve (17) is closed.

[0117] According to the configuration described in [5] above, during defrosting and warming operations of the refrigerator (3), relatively high-temperature warm air (circulating gas) extracted from upstream of the heat exchanger (8) of the compressed gas line (6) is introduced into the components and flow paths of the refrigerator (3). During defrosting and warming operations of the refrigerator (3), the refrigerated container (1) reduces the rotational speed of the electric motor (44) using the rotational speed control device (45), thereby suppressing the warm air (circulating gas) from becoming excessively hot, and thus suppressing thermal damage to the components and flow paths of the refrigerator (3). By suppressing thermal damage to the components and flow paths of the refrigerator (3), the refrigerated container (1) can improve the reliability of the components and flow paths of the refrigerator (3).

[0118] [6] In some embodiments, a refrigerated container (1) according to any of [1] to [5] above, wherein the chiller (3) includes a cooler (9) configured to perform heat exchange between the compressed gas flowing upstream of the heat exchanger (8) of the compressed gas line (6) and a coolant, and the upstream end (111) of the warm air line (11) is connected upstream of the cooler (9) of the compressed gas line (6).

[0119] According to the configuration described in [6] above, by connecting the upstream end (111) of the warm air line (11) of the refrigerated container (1) upstream of the cooler (9) of the compressed gas line (6), high-temperature circulating gas (warm air) can be flowed through the warm air line (11) compared to when it is connected between the cooler (9) and the heat exchanger (8) of the compressed gas line (6), thereby promoting defrosting of the chiller (3) by the warm air.

[0120] [7] In some embodiments, a refrigerated container (1) according to any of [1] to [6] above, wherein a refrigerated casing (100) is disposed inside the container body (2) and has a refrigerated casing (101) inside which the refrigerated unit (3) is housed, and the refrigerated casing (100) includes at least a back plate portion (102) extending in a direction perpendicular to the longitudinal direction of the container body (2) on the side of the refrigerated casing (20) from the refrigerated unit (3), and a pair of side plate portions (105, 106) extending in a direction perpendicular to the width direction of the container body (2) and covering the refrigerated unit (3), The container body (2) is provided with an inlet box (300) for guiding the circulating gas from the refrigeration space (20) to the refrigerator (3), the inlet box (300) protruding from the back plate portion (102) toward the refrigerator housing space (101) and having an internal box space (301) which is an internal space connected to the refrigeration space (20), and the heat exchanger (8) is positioned between one of the pair of side plate portions (105, 106) and the inlet box (300) in the width direction of the container body (2), and an intake portion (81) for taking the circulating gas into the heat exchanger (8) is connected to the inlet box (300).

[0121] According to the configuration described in [7] above, the refrigerated container (1) can be made more compact by arranging the entrance box (300) inside the refrigeration unit casing (100), thereby utilizing the internal space of the container body (2). The refrigerated container (1) can be made more compact by arranging the heat exchanger (8), which has a relatively large volume in the refrigeration unit (3), between the side plate section (105) and the entrance box (300).

[0122] Furthermore, according to the configuration described in [7] above, the intake portion (81) of the heat exchanger (8) of the refrigerated container (1) is connected to the inlet box (300), so the heat exchanger (8) can be supported by the inlet box (300), thereby improving the reliability of the refrigeration unit (3) against vibrations that occur when transporting the refrigerated container 1.

[0123] [8] In some embodiments, the refrigerated container (1) described in [7] above, wherein the entrance box (300) includes at least a first side plate (304) that faces the one side plate portion (105) of the refrigeration casing (100) in the width direction of the container body (2) across the refrigeration housing space (101), and the first side plate (304) has a connection port (306) formed thereon to which the intake portion (81) of the heat exchanger (8) is connected, and the intake portion (81) of the heat exchanger (8) extends linearly along the width direction of the container body (2) and is connected to the connection port (306).

[0124] According to the configuration described in [8] above, the length and surface area of ​​the intake section (81) of the heat exchanger (8) can be reduced in the refrigerated container (1), which allows for a more compact refrigerator (3) and also suppresses heat input from outside the intake section (81) to the circulating gas flowing through the intake section (81).

[0125] [9] In some embodiments, the refrigerated container (1) described in [7] or [8] above, wherein the inlet box (300) includes at least: a first side plate (304) that faces the one side plate portion (105) of the refrigeration casing (100) in the width direction of the container body (2) across the refrigeration housing space (101), and having a connection port (306) formed therein to which the intake portion (81) of the heat exchanger (8) is connected; and a second side plate (305) that faces the first side plate (304) in the width direction of the container body (2) across the box internal space (301), and having a drain discharge hole (308) formed below the connection port (306).

[0126] According to the configuration described in [9] above, frost accumulated in the box interior space (301) may melt due to normal operation or defrosting of the refrigerator (3), or natural melting after operation of the refrigerator (3), generating drain. The refrigerated container (1) has drain discharge holes (308) formed in the second side plate (305), allowing drain to be discharged from the box interior space (301) to the outside of the inlet box (300) via the drain discharge holes (308).

[0127]

[10] In some embodiments, the refrigerated container (1) described in [9] above, wherein the inlet box (300) includes an inclined plate (309) connected below the connection port (306) of the first side plate (304) and below the drain discharge hole (308) of the second side plate (305), the inclined plate (309) inclined downward toward the second side plate (305) in the width direction of the container body (2).

[0128] According to the configuration described in

[10] above, the refrigerated container (1) can guide the drain present in the box interior space (301) to the second side plate (305) where the drain discharge hole (308) is formed, due to the inclination of the inclined plate (309), thereby improving the drain discharge performance of the inlet box (300).

[0129] 1 Refrigerated container 2 Container body 3 Refrigeration unit 4 Turbomachinery 5 Inlet line 6 Compressed gas line 7 Outlet line 8 Heat exchanger 9 Cooler 11 Warm air line 12 Warm air line side flow control valve 13 Bypass line 14 Connection line 15 Bypass line side flow control valve 16 Connection line side flow control valve 17 Compressed gas line side flow control valve 20 Refrigerated space 41 Compressor 42 Turbine 43 Rotating shaft 44 Electric motor 45 Rotation speed control device 51 Inlet 51A First inlet 51B Second inlet 52 Inlet side communication hole 71 Outlet 72 Outlet side communication hole 73 Turbine outlet piping 81 Intake section 100 Refrigeration unit casing 101 Refrigeration unit housing space 102 Back plate section 102A First back plate section 102B Inclined section 102C Flat section 200 Insulation material 300 Inlet box 301 Box interior space 302 Front panel 303 Bottom panel 304 First side panel 305 Second side panel 306 Connection port 308 Drain discharge hole 309 Inclined plate 600 Inlet flow path forming section 601 Inlet flow path 700 Outlet flow path forming section 701 Outlet flow path 800 Laying member 801 Top surface 802 Gas flow path

Claims

1. A refrigerated container comprising: a container body having a refrigerated space to be cooled inside; and a refrigerator configured to cool circulating gas drawn in from the refrigerated space, wherein the refrigerator includes: a compressor configured to compress the circulating gas; a turbine configured to expand the circulating gas; an inlet line for leading the circulating gas from the refrigerated space to the compressor; a compressed gas line for leading the compressed gas, which is the circulating gas compressed by the compressor, to the turbine; an outlet line for leading the circulating gas, which has been expanded by the turbine, into the refrigerated space; a heat exchanger configured to perform heat exchange between the circulating gas flowing through the inlet line and the compressed gas flowing through the compressed gas line; a warm air line for drawing out the circulating gas from the upstream side of the heat exchanger in the compressed gas line and leading it to the upstream side of the heat exchanger in the inlet line; and a warm air line side flow control valve provided in the warm air line and configured to adjust the flow rate of the compressed gas flowing through the warm air line.

2. The warm air line includes a bypass line for extracting the circulating gas from the compressed gas line upstream of the heat exchanger and guiding it to the compressed gas line downstream of the heat exchanger; and a connecting line whose upstream end is connected to either the compressed gas line downstream of the heat exchanger or the bypass line, and whose downstream end is connected to the inlet line upstream of the heat exchanger; the warm air line side flow control valve includes a bypass line side flow control valve configured to adjust the flow rate of the circulating gas flowing through the bypass line; and a connecting line side flow control valve configured to adjust the flow rate of the circulating gas flowing through the connecting line; and the refrigerator further includes a compressed gas line side flow control valve configured to adjust the flow rate of the compressed gas flowing downstream of the connection to the upstream end of the bypass line and upstream of the connection to the downstream end of the bypass line in the compressed gas line, the refrigerated container according to claim 1.

3. The refrigerated container according to claim 2, wherein the upstream end of the connection line is connected to the bypass line.

4. The refrigerated container according to claim 2, wherein the upstream end of the connection line is connected downstream of the heat exchanger in the compressed gas line.

5. The refrigeration unit includes an electric motor configured to generate a rotational force to rotate the compressor, and a rotational speed control device for controlling the rotational speed of the electric motor, wherein the rotational speed control device is configured to reduce the rotational speed of the electric motor when either the bypass line side flow control valve or the connecting line side flow control valve is opened, or when the compressed gas line side flow control valve is closed, the refrigerated container according to any one of claims 2 to 4.

6. The refrigeration unit includes a cooler configured to perform heat exchange between the compressed gas flowing upstream of the heat exchanger in the compressed gas line and a coolant, and the upstream end of the warm air line is connected upstream of the cooler in the compressed gas line, according to any one of claims 1 to 4.

7. A refrigerator casing disposed inside the container body and having a refrigerator housing space inside which the refrigerator is housed, the refrigerator casing comprising at least: a back plate portion extending in a direction perpendicular to the longitudinal direction of the container body on the side of the refrigerator to the refrigerator housing space, and a pair of side plate portions extending in a direction perpendicular to the width direction of the container body and covering the refrigerator; and an inlet box for guiding the circulating gas from the refrigerator to the refrigerator, the inlet box protruding from the back plate portion toward the refrigerator housing space and having an internal box space which is an internal space connected to the refrigerator housing space, wherein the heat exchanger is disposed between one of the pair of side plate portions and the inlet box in the width direction of the container body, and an intake portion for taking in the circulating gas into the heat exchanger is connected to the inlet box, the refrigerator container according to any one of claims 1 to 4.

8. The inlet box includes at least a first side plate that faces the one side plate portion of the refrigeration casing in the width direction of the container body, with the refrigeration housing space in between, and having a connection port formed therein to which the intake portion of the heat exchanger is connected, wherein the intake portion of the heat exchanger extends linearly along the width direction of the container body and is connected to the connection port, the refrigeration container according to claim 7.

9. The refrigerated container according to claim 7, wherein the inlet box comprises at least: a first side plate that faces the one side plate portion of the refrigeration casing in the width direction of the container body, across the refrigeration housing space, and having a connection port formed therein for connecting the intake portion of the heat exchanger; and a second side plate that faces the first side plate in the width direction of the container body, across the box internal space, and having a drain discharge hole formed below the connection port.

10. The refrigerated container according to claim 9, wherein the inlet box includes an inclined plate connected below the connection port of the first side plate and below the drain discharge hole of the second side plate, the inclined plate being inclined downward in the width direction of the container body toward the second side plate.

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