Cooling system, refrigeration system unit, and flow path assembly

Abstract

To provide a cooling system that performs a desired cooling treatment on the air to be temperature-controlled, thereby preventing adverse effects on the temperature-controlled space caused by the temperature-controlled air, and enabling stable and efficient temperature control of the temperature-controlled space. [Solution] A cooling system 1 according to one embodiment comprises two refrigeration system units 2a and 2b. Each of the refrigeration system units 2a and 2b comprises a refrigeration unit CU having at least one refrigerator 10, a case 30 having a first inlet 31A and a first outlet 31B and a second inlet 32A and a second outlet 32B, housing one evaporator 14 of the refrigeration unit CU between the first inlet 31A and the first outlet 31B, and housing another evaporator 24 of the refrigeration unit CU between the second inlet 32A and the second outlet 32B, and a connection chamber 40 connected to the first outlet 31A and the second outlet 31B and communicating with the space to be temperature controlled.

Description

[Technical Field]

[0001] The present invention relates to a cooling system, a refrigeration system unit, and a flow path assembly for stably controlling the temperature of chemical storage and the like. [Background Art]

[0002] When controlling the temperature of a temperature-controlled space such as a storage, a vapor compression refrigerator (hereinafter referred to as a refrigerator) is generally used. A refrigerator includes a compressor, a condenser, an expansion valve, and an evaporator. In a configuration where temperature control is performed by a refrigerator, the air in the temperature-controlled space is repeatedly cooled by the evaporator, and the temperature of the temperature-controlled space is maintained at a target temperature.

[0003] In the evaporator of a refrigerator, a freezing phenomenon called frosting may occur when the evaporation temperature set according to the target temperature of the temperature-controlled space is set to a low temperature. When frosting occurs, the heat exchange efficiency of the evaporator may decrease. Therefore, some refrigerators that are expected to generate frosting are periodically subjected to a defrosting process called defrosting.

[0004] When defrosting is performed, the operation of the refrigerator is normally stopped, so the temperature control by the stopped refrigerator is interrupted. Therefore, when uniform temperature control is constantly required, a plurality of refrigerators may be installed for one temperature-controlled space. In this aspect, when some refrigerators are in defrosting, cooling can be performed by other refrigerators, thereby enabling continuous temperature control (see, for example, Patent Document 1). [Prior Art Literature] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Laid-Open No. 2019-207090 [Summary of the Invention] [Problem to be Solved by the Invention]

[0006] There are two methods for defrosting: one that heats the evaporator with a heater (electric heater method) and another that melts the frost on the evaporator using air in the temperature-controlled space (off-cycle method). Of these, the method that uses air for defrosting has the advantage of reducing energy consumption. However, for example, during low-load operation of a chiller, if the surface temperature of the evaporator coil drops and excessive frost buildup occurs to balance the load, it may not be possible to properly complete defrosting with air.

[0007] Furthermore, during low-load operation of the refrigeration unit, the air flowing out of the evaporator may become excessively cold due to a decrease in the surface temperature of the evaporation coil, similar to the above. If the temperature of the air flowing out of the evaporator drops excessively, adverse effects may occur at the destination of the air. For example, if temperature control is being performed in a storage facility, there is a risk of quality deterioration due to overcooling of stored goods or freezing damage. While it is possible to raise the temperature of the air using a heater, this would complicate the equipment structure and increase the energy cost of the heater.

[0008] On the other hand, as a countermeasure against the excessive drop in air temperature mentioned above, the amount of air supplied through the evaporator may be increased from the planned rate, thereby raising the temperature of the air discharged from the evaporator. However, raising the temperature of the air discharged from the evaporator may not always be desirable. It is well known that increased airflow leads to increased transport power consumption, but for example, if it is desirable to perform dew point treatment at a desired level in the evaporator, raising the temperature of the air discharged from the evaporator is undesirable. Specifically, if the temperature of the air discharged from the evaporator is raised, the humidity of the discharged air may not decrease sufficiently, reducing the latent heat treatment of the evaporator and potentially increasing the amount of untreated moisture. As a result, the dew point of the atmosphere inside the chamber rises, and the humidity inside the chamber may reach the condensation limit. Since the evaporator, which operates at a lower temperature than the surrounding air, removes heat at a lower temperature than the air inside the chamber (temperature difference of 5-15K or less, etc.), condensation may occur around the cooler chamber housing the evaporator. In addition, water vapor from the untreated moisture in the evaporator is lighter than the specific gravity of air and rises easily. Therefore, when using ceiling-mounted air conditioners that send air from the evaporator to the ceiling, or when using ceiling duct discharge methods, condensation is likely to occur around the ceiling outlet. In such situations, there are concerns about condensation water adhering to stored items, condensation damage to stored items, and resulting mold contamination.

[0009] The present invention was conceived against the above background, and aims to provide a cooling system, a refrigeration system unit, and a flow path assembly that can perform a desired cooling treatment on air to be temperature controlled, thereby preventing adverse effects on the temperature-controlled space caused by the temperature-controlled air, and enabling stable and efficient temperature control of the temperature-controlled space. [Means for solving the problem]

[0010] Embodiments of the present invention relate to the following aspects.

[0011] A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connecting chamber connected to the first outlet and the second outlet and communicating with the space to be temperature controlled, A cooling system with two or more units.

[0012] A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connecting chamber connected to the first outlet and the second outlet, and communicating with a space to be temperature controlled.

[0013] A case having a first inlet and a first outlet, and a second inlet and a second outlet, with an evaporator housed between the first inlet and the first outlet, and another evaporator different from the first evaporator housed between the second inlet and the second outlet, A flow path assembly comprising a connecting chamber connected to the first outlet and the second outlet, and communicating with a temperature-controlled space. [Effects of the Invention]

[0014] According to the present invention, a desired cooling treatment is applied to the air to be temperature-controlled, and the temperature of the space to be temperature-controlled can be stably and efficiently controlled while avoiding adverse effects on the space to be temperature-controlled caused by the temperature-controlled air. [Brief explanation of the drawing]

[0015] [Figure 1] This is a schematic diagram of a cooling system according to one embodiment. [Figure 2]It is a side view of the cooling system in Fig. 1. [Figure 3] It is a perspective view from the front side of the refrigeration system unit in the cooling system according to one embodiment. [Figure 4] It is a perspective view from the side surface side of the refrigeration system unit in the cooling system according to one embodiment. [Figure 5] It is a flowchart explaining the operation of the cooling system according to one embodiment. [Figure 6] It is a diagram explaining the operation of the cooling system according to one embodiment. [Figure 7] It is a schematic diagram of a cooling system according to another embodiment. [Figure 8] It is a schematic diagram of a cooling system according to still another embodiment. [Figure 9] It is a schematic diagram of a cooling system according to yet another embodiment. DETAILED DESCRIPTION OF EMBODIMENTS

[0016] Hereinafter, a cooling system 1 according to one embodiment will be described.

[0017] <Configuration of Cooling System> Fig. 1 is a schematic diagram of the cooling system 1, and Fig. 2 is a side view of the cooling system 1 in Fig. 1. In the present embodiment, an example will be described in which the cooling system 1 performs temperature control for a chemical storage S, but the application of the cooling system 1 is not particularly limited.

[0018] In the present embodiment, the cooling system 1 includes two refrigeration system units 2 (2a, 2b). The refrigeration system units 2a, 2b are devices of floor-mounted type having a cooling source (a portion including evaporators 14 and 24 to be described later), but are not limited to the floor-mounted type, and for example, a suspension type in which the cooling source is suspended may be employed.

[0019] Since refrigeration system units 2a and 2b have the same configuration, the following description will focus on the configuration of refrigeration system unit 2a, and the description of the configuration of refrigeration system unit 2b, which is the same as that of refrigeration system unit 2a, will be omitted. Figure 3 is a perspective view of refrigeration system unit 2a from the front, and Figure 4 is a perspective view of refrigeration system unit 2a from the side.

[0020] The refrigeration system unit 2a comprises a refrigeration unit CU having at least one refrigerator, a case 30, and a connection chamber 40.

[0021] In this embodiment, the refrigeration unit CU comprises a first refrigerator 10 and a second refrigerator 20. The first refrigerator 10 comprises a compressor 11, a condenser 12, an expansion valve 13, and an evaporator 14. In this example, the evaporator 14 is divided into two parts, including a first heat exchange section 14a and a second heat exchange section 14b. The flow path downstream of the condenser 12 branches into two, and a first expansion valve 13a corresponding to the first heat exchange section 14a is provided in one of the branched flow paths. A second expansion valve 13b corresponding to the second heat exchange section 14b is provided in the other branch. However, the evaporator 14 does not necessarily have to be divided.

[0022] The second refrigerator 20 includes a compressor 21, a condenser 22, an expansion valve 23, and an evaporator 24. The evaporator 24 is also divided into two sections, including a first heat exchange section 24a and a second heat exchange section 24b. The downstream flow path of the condenser 22 branches into two, with a first expansion valve 23a corresponding to the first heat exchange section 24a provided in one of the branched flow paths, and a second expansion valve 23b corresponding to the second heat exchange section 24b provided in the other. The evaporator 24 does not necessarily have to be divided.

[0023] The types of the first refrigerator 10 and the second refrigerator 20 are not particularly limited; they may be refrigerators that circulate a fluorine-based refrigerant, or refrigerators that circulate a natural refrigerant (such as a CO2 refrigerator that circulates carbon dioxide). However, in that case, the condenser 12 will function as a gas cooler.

[0024] In Figure 1, some components (compressor, condenser, etc.) of the first chiller 10 and the second chiller 20 are shown below the storage unit S for convenience. However, the compressors, condensers, etc. of the first chiller 10 and the second chiller 20 may be installed outdoors as outdoor units.

[0025] Case 30 is a housing portion that accommodates the evaporator 14 of the first refrigerator 10 and the evaporator 24 of the second refrigerator 20. As shown in Figures 3 and 4, Case 30 has a first inlet 31A and a first outlet 31B, and a second inlet 32A and a second outlet 32B. In Figure 3, for the sake of explanation, the positions of the first inlet 31A and the second inlet 32A are indicated by dashed lines.

[0026] Case 30 houses the evaporator 14 of the first refrigerator 10 between the first inlet 31A and the first outlet 31B, and the evaporator 24 of the second refrigerator 20 between the second inlet 32A and the second outlet 32B.

[0027] Case 30 is rectangular in shape and rises up with its bottom in contact with the floor of the storage room S. That is, the evaporators 14 and 24, which serve as cooling sources, are installed on the floor of the storage room S via Case 30. In this example, the first inlet 31A and the second inlet 32A open forward from the front wall of Case 30. In this example, the first inlet 31A and the second inlet 32A are aligned laterally (left-right) and open forward in the same direction.

[0028] The first inlet 31A and the second inlet 32A each consist of a pair corresponding to the divided evaporators 14 and 24. However, if the evaporators 14 and 24 are not divided, the first inlet 31A and the second inlet 32A may be formed as a single opening.

[0029] In this example, the first inlet 31A and the second inlet 32A open forward, but they may open to the left, right, or rear. Furthermore, the first inlet 31A and the second inlet 32A may open in different directions. Note that the first inlet 31A and the second inlet 32A do not necessarily open strictly along the horizontal direction; for example, they may open diagonally downwards with a horizontal component. In Figure 4, the first inlet 31A and the second inlet 32A are covered with filters.

[0030] The first outlet 31B and the second outlet 32B open upward from the upper wall of the case 30. In this example, the first outlet 31B and the second outlet 32B are aligned horizontally (left-right) and open upward in the same direction. The opening direction of the first outlet 31B and the second outlet 32B can be forward, left, right, or rear, as long as it is in the same direction.

[0031] As shown in Figure 3, in case 30, a first air passage 33 is formed between a first inlet 31A and a first outlet 31B, and a second air passage 34 is formed between a second inlet 32A and a second outlet 32B. The evaporator 14 of the first refrigerator 10 is located on the first passage 33. The evaporator 24 of the second refrigerator 20 is located on the second passage 34.

[0032] When viewed from the front of the first inlet 31A (viewpoint in Figure 3), the first outlet 31B is located above the first inlet 31A. When viewed from the front of the second inlet 32A, the second outlet 32B is located above the second inlet 32A. A partition wall 30D is formed inside the case 30, separating the first flow path 33 and the second flow path 34. As a result, air flowing into the case 30 from the first inlet 31A flows linearly through the first flow path 33 toward the first outlet 31B after entering the case 30. Similarly, air flowing into the case 30 from the second inlet 32A flows linearly through the second flow path 34 toward the second outlet 32B after entering the case 30.

[0033] The air flowing through the first channel 33 is cooled in the evaporator 14 of the first chiller 10 and then flows out from the first outlet 31B. The air flowing through the second channel 34 is cooled in the evaporator 24 of the second chiller 20 and then flows out from the second outlet 32B. The evaporators 14 and 24 are not particularly limited as long as they use an air cooling system, and in terms of structural classification they are generally of the fin tube coil type, but for example, plate fin coil type, macro channel type, or bare tube type may also be used. In terms of refrigerant classification, direct expansion type, chilled water coil type, or brine coil type may also be used.

[0034] As shown in Figure 4, the heat exchange sections 14a and 14b of the evaporator 14 are each flat fin coils (fin tube coils), and are arranged so that the upper part is closer to the first inlet 31A than the lower part and the front and rear surfaces are inclined. The heat exchange sections 24a and 24b of the evaporator 24 are the same shape as the heat exchange sections 14a and 14b and are arranged in the same manner. Note that the arrangement of the evaporators 14 and 24 is not limited to the illustrated example, and they may be arranged so that the front and rear surfaces are horizontal or vertical.

[0035] Furthermore, a blower 35, a heater 36, and a damper 37 are provided inside the case 30. The blower 35 draws outside air into the case 30 from a first inlet 31A and a second inlet 32A. In this example, the blower 35 includes a first blower 35a and a second blower 35b. The first blower 35a draws outside air into the case 30 from a first inlet 31A, and the second blower 35b draws outside air into the case 30 from a second inlet 32A.

[0036] The first blower 35a is positioned between the evaporator 14 and the first outlet 31B, and the second blower 35b is positioned between the evaporator 24 and the second outlet 32B. However, the positions of the first blower 35a and the second blower 35b are not particularly limited. Alternatively, a configuration may be adopted in which external air is drawn into the first inlet 31A and the second inlet 32A by driving a single blower 35.

[0037] The heater 36 is a device for heating air and includes a first heater 36a and a second heater 36b. The first heater 36a is provided in the first flow path 33 and heats the air flowing through the first flow path 33. The second heater 36b is provided in the second flow path 34 and heats the air flowing through the second flow path 34.

[0038] The heater 36 may be used as a heating source to prevent frost buildup on the evaporator coil (the coil portion of the evaporator) or to avoid the temperature inside the refrigerator falling below the lower limit of the storage temperature control when the refrigerator is overcooled and operating at a low load, for example in winter, due to the natural increase in refrigeration capacity caused by the decrease in outside temperature. Furthermore, if dehumidification inside the refrigerator is required, it may be used as a reheat heater heat source operated simultaneously with the evaporator coil. Note that the heater 36 may not be provided in some cases, as power consumption can be reduced by balancing the load through control of the number of evaporators and INV control, thereby decreasing its usage frequency.

[0039] The damper 37 includes a first damper 37a that suppresses the inflow of air from the first outlet 31B to the second outlet 32B, and a second damper 37b that suppresses the inflow of air from the second outlet 32B to the first outlet 31B. The first damper 37a is provided so as to cover the first outlet 31B. The second damper 37b is provided so as to cover the second outlet 32B. The first damper 37a and the second damper 37b are not particularly limited, but may be composed of wind pressure dampers. The first damper 37a and the second damper 37b are configured to open in accordance with the airflow from the inlet to the outlet, and to close when air flows from the outlet to the inlet.

[0040] Referring to Figures 1 to 4, the connecting chamber 40 is a component for connecting to the relay duct 50 and mixing the air cooled by the evaporators 14 and 24, and is connected to the first outlet 31B and the second outlet 32B. In this example, the first outlet 31B and the second outlet 32B are each connected to the connecting chamber 40 via a pipe 31T that extends in the vertical direction. The connecting chamber 40 is a cylindrical body including a tapered portion that narrows toward the downstream side. The connecting chamber 40 is connected to the first outlet 31B and the second outlet 32B such that its axial direction is aligned with the vertical direction. The filters provided to cover the first inlet 31A and the second inlet 32A may be installed before and after the connecting chamber 40 (upstream and downstream sides). In this embodiment, the structure formed by combining the case 30 and the connecting chamber 40 constitutes the flow path assembly.

[0041] As shown in Figures 1 and 2, the connection chamber 40 is connected via a relay duct 50 to a common duct 60 located above the refrigeration system unit 2a. The common duct 60 is supported on the upper part (ceiling) of the storage unit S, extending horizontally. The common duct 60 has an outlet 60A, and in this example, it communicates with the internal space of the storage unit S, which is the temperature-controlled space, via a supply duct 70 connected to the outlet 60A. The supply duct 70 has a plurality of outlets 71, and the plurality of outlets 71 open into the temperature-controlled space, which is the internal section of the storage unit S.

[0042] In other words, the connection chamber 40 in this example communicates with the internal space of the storage unit S via the relay duct 50, the common duct 60, and the supply duct 70. Temperature-controlled air flowing out from the refrigeration system unit 2a can be supplied to the inside of the storage unit S. Similarly, the connection chamber 40 of the other refrigeration system unit 2b is also connected to the common duct 60, etc., and communicates with the internal space of the storage unit S. Temperature-controlled air flowing out from the refrigeration system unit 2b can also be supplied to the inside of the storage unit S.

[0043] In this embodiment, the cooling system 1 comprises two refrigeration system units 2a and 2b, which are an even number. In the cooling system 1, as shown in Figure 1, the connection chamber 40 of one of the two refrigeration system units 2a and 2b, and the connection chamber 40 of the other refrigeration system unit 2b, are distributed to one side and the other side of the common duct 60 with respect to the formation position of the outlet 60A, and are connected to the common duct 60 via an intermediate duct 50. It is desirable that the distance from the connection position of the connection chamber 40 of one refrigeration system unit 2a to the common duct 60 (more precisely, the connection position of the intermediate duct 50) to the outlet 60A, and the distance from the connection position of the connection chamber 40 of the other refrigeration system unit 2b to the common duct 60 (more precisely, the connection position of the intermediate duct 50) to the outlet 60A, are the same.

[0044] Next, the operation of the cooling system 1 will be explained. Figure 5 is a flowchart illustrating an example of the operation of the cooling system 1 during temperature control. When the cooling system 1 controls the temperature of the internal space of the storage cabinet S, it repeatedly cools the air inside the storage cabinet S using the evaporators 14 and 24 in the refrigeration system units 2a and 2b, thereby controlling the temperature inside the storage cabinet S to the desired temperature.

[0045] When temperature control is initiated, in step S101, the first chiller 10 in each refrigeration system unit 2a and 2b is operated. At this time, the second chiller 20 is stopped. That is, the first chiller 10 is operated with refrigerant flowing through its evaporator 14, while the second chiller 20 is operated without refrigerant flowing through its evaporator 24. Meanwhile, both the blowers 35 (first blower 35a and second blower 35b) in each refrigeration system unit 2a and 2b are operated.

[0046] In step S102, it is monitored whether a predetermined time has elapsed since the start of operation in step S101.

[0047] In step S102, once the predetermined time has elapsed, in step S103, the operation of the first chiller 10 in each refrigeration system unit 2a and 2b is stopped. Meanwhile, the blowers 35 (first blower 35a and second blower 35b) in each refrigeration system unit 2a and 2b continue to operate. At this time, in the first chiller 10 in each refrigeration system unit 2a and 2b, defrosting (off-cycle defrosting) is performed by passing air through the evaporator 14 due to the operation of the blowers 35.

[0048] Next, in step S104, the second chillers 20 in each refrigeration system unit 2a and 2b are operated. That is, the first chiller 10 is operated without circulating refrigerant through its evaporator 14, while the second chiller 20 is operated with refrigerant circulating through its evaporator 24.

[0049] Subsequently, in step S105, it is monitored whether a predetermined time has elapsed since the start of operation in step S104.

[0050] In step S105, once the predetermined time has elapsed, in step S106, the operation of the second chiller 20 in each refrigeration system unit 2a and 2b is stopped. Meanwhile, the blowers 35 (first blower 35a and second blower 35b) in each refrigeration system unit 2a and 2b continue to operate. At this time, in the second chiller 20 in each refrigeration system unit 2a and 2b, defrosting (off-cycle defrosting) is performed by passing air through the evaporator 24 due to the operation of the blowers 35. After that, the process returns to step S101, and the operation of the first chiller 10 is restarted.

[0051] In other words, in the cooling system 1, the first chiller 10 and the second chiller 20 in each refrigeration system unit 2a and 2b switch between operation and shutdown at predetermined intervals. Meanwhile, the blowers 35 (first blower 35a, second blower 35b) for circulating air in each refrigeration system unit 2a and 2b are operated continuously. That is, regardless of whether the first chiller 10 or the second chiller 20 is stopped, the blowers 35 are operated so that air flowing from the first inlet 31A through the evaporator 14 of the first chiller 10 and out of the first outlet 31B, and air flowing from the second inlet 32A through the evaporator 24 of the second chiller 20 and out of the second outlet 32B both flow into the connection chamber 40.

[0052] Figures 6(A) and (B) are explanatory diagrams of the operation, showing how the first chiller 10 and the second chiller 20 in each refrigeration system unit 2a and 2b can be switched between operation and stop.

[0053] In Figure 6(A), the first chiller 10 is operating and the second chiller 20 is stopped in each refrigeration system unit 2a and 2b. The solid arrows shown on the first chiller 10 indicate the airflow whose temperature is controlled by the evaporator 14, and the dashed arrows shown on the second chiller 20 indicate the airflow passing through the evaporator 24 without temperature control by the evaporator 24.

[0054] In Figure 6(B), the second chiller 20 is operating in each refrigeration system unit 2a and 2b, while the first chiller 10 is stopped. The solid arrows shown on the second chiller 20 indicate the airflow whose temperature is controlled by the evaporator 24, while the dashed arrows shown on the first chiller 10 indicate the airflow passing through the evaporator 14 without temperature control.

[0055] In cooling system 1, in each refrigeration system unit 2a, 2b, either the first chiller 10 or the second chiller 20 is operated while the other is stopped. However, the blowers 35 (first blower 35a, second blower 35b) for circulating air in each refrigeration system unit 2a, 2b are always in operation. As a result, air whose temperature is controlled by either the evaporator 14 of the first chiller 10 or the evaporator 24 of the second chiller 20 mixes in the connecting chamber 40 with air that has passed through without temperature control by the other, and flows out to the downstream side. At this time, the air that flows out to the downstream side flows out at a temperature higher than the low-temperature air cooled by the evaporator 14 or evaporator 24, depending on the air mixing ratio. In this case, the air volume per evaporator is the same, and in the connecting chamber 40, the temperature rises to about half the cooling temperature difference of the operating evaporators before flowing out to the downstream side.

[0056] Furthermore, the blowers 35 (first blower 35a, second blower 35b) are operated continuously. As a result, when the evaporator 14 of the first chiller 10 or the evaporator 24 of the second chiller 20 is stopped, defrosting with air (off-cycle defrosting) is performed on the evaporator 14 or evaporator 24, removing frost buildup.

[0057] The cooling system 1 according to this embodiment described above comprises two refrigeration system units 2a and 2b. Each of the refrigeration system units 2a and 2b comprises a refrigeration unit CU equipped with at least one refrigerator (in this example, two refrigerators, a first refrigerator 10 and a second refrigerator 20), a case 30 having a first inlet 31A and a first outlet 31B and a second inlet 32A and a second outlet 32B, housing one evaporator 14 of the refrigeration unit CU between the first inlet 31A and the first outlet 31B, and housing another evaporator 24 of the refrigeration unit CU between the second inlet 32A and the second outlet 32B, and a connection chamber 40 connected to the first outlet 31B and the second outlet 32B and communicating with the space to be temperature controlled.

[0058] With such a cooling system 1, for example, by operating the first refrigerator 10 and stopping the second refrigerator 20, the air that passes from the first inlet 31A through the evaporator 14 of the first refrigerator 10 and flows into the connecting chamber 40 from the first outlet 31B can be mixed with the air that passes from the second inlet 32A through the evaporator 24 of the second refrigerator 20 and flows into the connecting chamber 40 from the second outlet 32B. This prevents a situation where, for example, the air passing through the evaporator 14 of the first refrigerator 10 flows into the temperature-controlled space at an excessively low temperature, such as below the internal limit temperature. As a result, for example, sufficient dehumidification of the air is performed in the evaporator 14 of the first refrigerator 10, while suppressing the occurrence of undesirable situations where air flows into the temperature-controlled space at an excessively low temperature. Furthermore, having two or more refrigeration system units 2a and 2b distributes the operating load of each refrigeration system unit, suppressing frost formation on the evaporators 14 and 24, and enabling proper defrosting with air. This is advantageous in terms of stable temperature control and energy saving. Consequently, adverse effects on the temperature-controlled space caused by temperature-controlled air can be suppressed, and the temperature of the temperature-controlled space can be controlled stably and efficiently.

[0059] Here, the cooling system 1 may be applied under the following conditions. The target temperature of the temperature-controlled space (the internal space of storage cabinet S) is set to a range of +2°C to +8°C, which is the refrigerated storage temperature for pharmaceuticals (prevention of deterioration due to freezing and suppression of deterioration due to high temperatures). • The evaporation temperature of the evaporators (14, 24) of the refrigerator during operation is set to be between -2°C and -8°C. In this case, due to the target temperature setting, frost is likely to form on the evaporator. However, frost formation is suppressed by distributing the heat load through the operation of multiple chillers (refrigeration system units 2a and 2b), and defrosting is efficiently performed by fan operation (defrosting) when the chillers are idle, allowing the cooling system to function particularly effectively. In addition, depending on the evaporation temperature setting, the temperature of the air cooled by the evaporator may be low (near freezing), but it can be heated up by mixing with air that is not temperature controlled. In this case, the evaporator can adequately handle the latent heat treatment (dehumidification) of air that flows into the storage area, for example, due to door ventilation during loading and unloading, while suppressing the undesirable situation that may occur when the air cooled by heat removal flows into the temperature-controlled space at a low temperature, such as below the limit temperature. More specifically, when performing off-cycle defrosting, it is desirable that the temperature of the air blown out from each refrigeration system unit 2a, 2b be above the freezing point of 0°C. Furthermore, when considering refrigerated storage of pharmaceuticals, it is desirable that the dew point of the blown air be near 0°C. In addition, when refrigerated storage of pharmaceuticals, the target temperature of the temperature-controlled space (the internal space of the storage cabinet S) is set to a range of +2°C to +8°C as described above. Cooling system 1 can supply air that satisfies the above desired conditions by mixing cooled air with air that has not been temperature-controlled (cooled). If only one evaporator is used, the desired dew point condition may be met, but the desired temperature condition of the blown air may not be met. Also, if only one evaporator is used, it is possible to create a situation where the desired temperature condition of the blown air is met by increasing the airflow rate, but in this case, the desired dew point condition will not be met. In contrast, cooling system 1 (each refrigeration system unit 2a, 2b) can satisfy both the desired dew point condition and the desired temperature condition of the blown air. Therefore, it can be said that cooling system 1 can function particularly effectively when applied under the conditions described above. However, the conditions under which cooling system 1 is applied are not particularly limited.

[0060] The embodiments described above are merely examples of how the present invention can be implemented, and it is possible to carry out the present invention in various other forms. For example, various modifications, substitutions, omissions, or combinations thereof are possible without departing from the spirit of the present invention. Such modified, substituted, or omission forms are also included within the scope of the present invention, as well as within the scope of the invention and its equivalents as described in the claims.

[0061] Figure 7 shows a cooling system according to another embodiment. Components in the other embodiment that are the same as those in the above-described embodiment are denoted by the same reference numerals, and redundant explanations are omitted.

[0062] In the other embodiment shown in Figure 7, the configuration of the refrigeration unit Cur1 in the refrigeration system units 2a and 2b differs from that of the embodiment described above. Each refrigeration unit Cur1 comprises only one refrigerator 10. The refrigerator 10 comprises a compressor 11, a condenser 12, an expansion valve 13, and two evaporators 14 and 24. The flow path downstream of the condenser 12 branches into two, and a first expansion valve 13a corresponding to the evaporator 14 is provided in one of the branched flow paths. A second expansion valve 13b corresponding to the evaporator 24 is provided in the other branch. In other words, the refrigerator 10 in this example comprises two evaporators 14 and 24 arranged in parallel. One of the two evaporators 14 and 24 is housed between the first inlet 31A and the first outlet 31B in the case 30, and the other is housed between the second inlet 32A and the second outlet 32B.

[0063] In the configuration shown in Figure 7, when the compressor 11 is operated, one of the first expansion valve 13a and the second expansion valve 13b is opened and the other is closed, and the switching of opening and closing is performed at predetermined intervals. The blower 35 is operated continuously as in the embodiment described above, and off-cycle defrosting is performed in the evaporator on the side where the expansion valve is closed during that closing period.

[0064] In yet another embodiment shown in Figure 8, similar to the configuration in Figure 7, the refrigerator unit Cur2 in the refrigeration system units 2a and 2b each comprises only one refrigerator 10', but the configuration of the refrigerator 10' differs from that in Figure 7. That is, in the embodiment shown in Figure 8, the compressor 11 of the refrigerator 10' includes a first compressor 11a and a second compressor 11b. The first compressor 11a and the second compressor 11b are arranged in parallel downstream of the evaporators 14 and 24. Basically, when one of the first compressor 11a and the second compressor 11b is operated, the other is stopped, but both may be operated simultaneously.

[0065] In the configuration shown in Figure 8, when either the first compressor 11a or the second compressor 11b is in operation, one of the first expansion valve 13a or the second expansion valve 13b is opened and the other is closed, and the switching of opening and closing is performed at predetermined intervals. The blower 35 is operated continuously as described above, and off-cycle defrosting is performed in the evaporator on the side where the expansion valve is closed during that closing period. The configuration shown in Figure 8 is advantageous in that operation can be continued even if either the first compressor 11a or the second compressor 11b fails, and is also advantageous in terms of ensuring refrigeration capacity.

[0066] In yet another embodiment shown in Figure 9(A), the cooling system comprises four refrigeration system units 2a, 2b, 2c, and 2d, which are an even number. The configuration of refrigeration system units 2c and 2d is the same as that of refrigeration system units 2a and 2b described in Figure 1, etc., but the configuration shown in Figure 7 or Figure 8 is also acceptable. In this example, the connection chambers 40 of half of the four refrigeration system units 2a and 2b and the connection chambers 40 of the remaining half of the refrigeration system units 2c and 2d are distributed to one side and the other side of the common duct 60 with respect to the formation position of the outlet 60A in the common duct 60, and connected to the common duct 60.

[0067] In another embodiment shown in Figure 9(B), the cooling system comprises five refrigeration system units 2a, 2b, 2c, 2d, and 2e, which is an odd number. The configuration of refrigeration system unit 2e is the same as that of the other refrigeration system units 2a to 2d. In this example, the connection chambers 40 of half of the even-numbered refrigeration system units (2a and 2b) and the connection chambers 40 of the remaining half (2c and 2d) are distributed to the common duct 60, one on one side and the other on the other side of the outlet 60A formation location in the common duct 60, and connected to the common duct 60. On the other hand, the connection chamber 40 of the remaining refrigeration system unit 2e is connected to the common duct 60 such that its downstream end is on the same plane as the outlet 60A in the common duct 60.

[0068] <Note> The configuration of the above-described embodiment is shown below.

[0069] <1> A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connecting chamber connected to the first outlet and the second outlet and communicating with the space to be temperature controlled, A cooling system with two or more units. As a result, for example, by operating the first chiller and stopping the second chiller as shown in the example in Figure 1, it is possible to mix the air that passes through the evaporator of the first chiller from the first inlet and flows into the connecting chamber from the first outlet with the air that passes through the evaporator of the second chiller from the second inlet and flows into the connecting chamber from the second outlet. This prevents, for example, the air passing through the evaporator of the first chiller from flowing into the temperature-controlled space at an excessively low temperature. This makes it possible to suppress the undesirable situation that may occur when, for example, the air cooled by heat removal flows into the temperature-controlled space at a low temperature, such as below the limit temperature, while the air is sufficiently dehumidified in the evaporator of the first chiller. In addition, having two or more chiller system units distributes the operating load of each chiller system unit (partial load following), suppresses frost formation on the evaporator, and enables proper defrosting with air, which is advantageous in terms of stable temperature control and energy saving. Therefore, adverse effects in the temperature-controlled space caused by temperature-controlled air can be suppressed, and the temperature of the temperature-controlled space can be controlled stably and efficiently. <2> Each of the refrigeration system units is capable of supplying air that passes from the first inlet through the evaporator and flows into the connection chamber from the first outlet, and air that passes from the second inlet through the other evaporator and flows into the connection chamber from the second outlet, to the temperature-controlled space via the connection chamber. <1> The cooling system described above. <3> In each of the aforementioned refrigeration system units, when refrigerant is circulated to either the evaporator or the other evaporator, the circulation of refrigerant to the other evaporator is suspended. <1> or <2> The cooling system described above. <4> Each of the refrigeration system units further comprises a blower for drawing outside air into the case from the first inlet and the second inlet. When refrigerant is circulated through either the evaporator or the other evaporator, and the circulation of refrigerant to the other is suspended, the blower is operated such that air passing through the evaporator from the first inlet and flowing out from the first outlet, and air passing through the other evaporator from the second inlet and flowing out from the second outlet, both flow into the connection chamber. <3> The cooling system described above.

[0070] <5> The connection chamber of each of the refrigeration system units is connected to a common duct having an outlet that communicates with the temperature-controlled space. <1> ~ <4> A cooling system as described in any of the following. This improves the flexibility of the supply location for temperature-controlled air. Furthermore, it is expected to further suppress temperature and humidity variations in the air supplied to the temperature-controlled space, thereby improving the stability of temperature control. <6> The cooling system comprises an even number of the aforementioned refrigeration system units. The connection chambers of half of the even-numbered refrigeration system units and the connection chambers of the remaining half of the refrigeration system units are distributed to one side and the other side of the common duct with respect to the outlet formation position in the common duct, and are connected to the common duct. <5> The cooling system described above. This allows for the uniform balance of airflow across different refrigeration system units while simultaneously supplying air to the temperature-controlled space, which is advantageous in terms of reducing energy consumption. <7> The first entrance and the second entrance open in any direction, either front, back, left, or right. The first outlet and the second outlet open upward. <1> ~ <6> A cooling system as described in any of the following. This allows for stable temperature control of a space, particularly large warehouses, by supplying air from above, while minimizing the system's footprint. <8> The air passage formed between the first inlet and the first outlet, and the air passage formed between the second inlet and the second outlet, are separated. <1> ~ <7> A cooling system as described in any of the following. This improves the stability of temperature control. <9> Each of the refrigeration system units further comprises a first damper that suppresses the inflow of air from the first outlet to the second outlet, and a second damper that suppresses the inflow of air from the second outlet to the first outlet. <1> ~ <8> A cooling system as described in any of the following. <10> The refrigerator unit includes a first refrigerator equipped with the evaporator and a second refrigerator equipped with the other evaporator. <1> ~ <9> A cooling system as described in any of the following. <11> A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connecting chamber connected to the first outlet and the second outlet, and communicating with a space to be temperature controlled. <12> A case having a first inlet and a first outlet, and a second inlet and a second outlet, with an evaporator housed between the first inlet and the first outlet, and another evaporator different from the first evaporator housed between the second inlet and the second outlet, A flow path assembly comprising a connecting chamber connected to the first outlet and the second outlet, and communicating with a temperature-controlled space. [Explanation of symbols]

[0071] 1…Cooling system 2(2a,2b)...Refrigeration system unit CU…Refrigeration unit 10…First Refrigeration Unit 11… Compressor 12... Condenser 13…Expansion valve 14… Evaporator 14a...First heat exchange section 14b...Second heat exchange section 20... Second Refrigeration Unit 21... Compressor 22... Condenser 23...Expansion valve 24... Evaporator 24a...First heat exchange section 24b…Second heat exchange section 30...cases 31A...First entrance 31B...First exit 32A...First entrance 32B...Second exit 31T…Pipe material 33…First channel 34…Second channel 35... Blower 35a…1st blower 35b…Second blower 37...Dump 37a...1st Damper 37b...2nd Dumper 40…Connection Chamber 50… relay duct 60... Common duct 70... Supply duct 71...Air outlet S…Storage

Claims

1. A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connection chamber connected to the first outlet and the second outlet and communicating with the space to be temperature controlled, A cooling system comprising two or more units, The refrigeration unit is a cooling system comprising a first refrigerator equipped with the evaporator and a second refrigerator equipped with the other evaporator.

2. The cooling system according to claim 1, wherein each of the refrigeration system units is capable of supplying air that passes from the first inlet through the evaporator and flows into the connection chamber from the first outlet, and air that passes from the second inlet through the other evaporator and flows into the connection chamber from the second outlet, to the temperature-controlled space via the connection chamber.

3. The cooling system according to claim 1, wherein in each of the refrigeration system units, when a refrigerant is circulated to either the evaporator or the other evaporator, the circulation of the refrigerant to the other evaporator is suspended.

4. Each of the refrigeration system units further comprises a blower for drawing outside air into the case from the first inlet and the second inlet. The cooling system according to claim 3, in which, when a refrigerant is circulated through either the evaporator or the other evaporator and the circulation of the refrigerant to the other is suspended, the blower is operated such that air passing through the evaporator from the first inlet and flowing out from the first outlet, and air passing through the other evaporator from the second inlet and flowing out from the second outlet, both flow into the connection chamber.

5. The cooling system according to claim 1, wherein the connection chamber of each of the refrigeration system units is connected to a common duct having an outlet that communicates with the temperature-controlled space.

6. The cooling system comprises an even number of the aforementioned refrigeration system units. The cooling system according to claim 5, wherein the connection chambers of half of the even-numbered refrigeration system units and the connection chambers of the remaining half of the refrigeration system units are distributed to one side and the other side of the common duct with respect to the outlet formation position in the common duct, and connected to the common duct.

7. The first entrance and the second entrance open in any direction, either front, back, left, or right. The cooling system according to claim 1, wherein the first outlet and the second outlet open upward.

8. The cooling system according to claim 1, wherein the air passage formed between the first inlet and the first outlet and the air passage formed between the second inlet and the second outlet are partitioned.

9. The cooling system according to claim 1, wherein each of the refrigeration system units further comprises a first damper that suppresses the inflow of air from the first outlet to the second outlet, and a second damper that suppresses the inflow of air from the second outlet to the first outlet.

10. A refrigeration unit comprising at least one chiller, A case having a first inlet and a first outlet, and a second inlet and a second outlet, with the evaporator of the refrigeration unit housed between the first inlet and the first outlet, and the other evaporator of the refrigeration unit housed between the second inlet and the second outlet, A refrigeration system unit comprising a connecting chamber connected to the first outlet and the second outlet and communicating with a temperature-controlled space, The refrigeration unit is a refrigeration system unit that includes a first refrigerator equipped with the evaporator and a second refrigerator equipped with the other evaporator.

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