GB2561097A

GB2561097A - Cooling warehouse

Info

Publication number: GB2561097A
Application number: GB1806458.4A
Authority: GB
Inventors: Okabe Yumei
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2015-12-25
Filing date: 2015-12-25
Publication date: 2018-10-03
Anticipated expiration: 2035-12-25
Also published as: JP6735774B2; CN108431529A; WO2017109932A1; GB2561097B; GB201806458D0; JPWO2017109932A1

Abstract

This cooling warehouse is equipped with: a warehouse body that comprises a heat insulation panel , and is formed with an introduction port through which outside air is introduced into the warehouse and a discharge port through which inside air is discharged to the outside of the warehouse; an introduction cover that is provided to the introduction port so as to open/close the introduction port; a discharge cover that is provided to the discharge port so as to open/close the discharge port; a leakage detection unit that is provided to the interior of the warehouse body so as to detect the leakage of a refrigerant; and a control unit that controls the introduction cover and the discharge cover so as to open the introduction port and the discharge port if the leakage of the refrigerant is detected by the leakage detection unit.

Description

(54) Title of the Invention: Cooling warehouse Abstract Title: Cooling warehouse (57) This cooling warehouse is equipped with: a warehouse body that comprises a heat insulation panel, and is formed with an introduction port through which outside air is introduced into the warehouse and a discharge port through which inside air is discharged to the outside of the warehouse; an introduction cover that is provided to the introduction port so as to open/close the introduction port; a discharge cover that is provided to the discharge port so as to open/close the discharge port; a leakage detection unit that is provided to the interior of the warehouse body so as to detect the leakage of a refrigerant; and a control unit that controls the introduction cover and the discharge cover so as to open the introduction port and the discharge port if the leakage of the refrigerant is detected by the leakage detection unit.

1/4

FIG. 1

100

FIG. 2

22 22

2/4

FIG. 3

100

FIG. 4

3/4

FIG. 5

200

6

FIG. 6

300 oo i.—y

4/4

FIG. 7

300

DESCRIPTION

Title of Invention

REFRIGERATED WAREHOUSE

Technical Field [0001]

The present invention relates to a refrigerated warehouse configured to discharge leaking refrigerant.

Background Art [0002]

Prefabricated refrigerators, prefabricated freezers, and other refrigerators and freezers are known as refrigerated warehouses, which allows entry and exit of a person, a forklift, or other machines. An interior of the refrigerated warehouse is cooled by a refrigeration cycle apparatus using refrigerant. An indoor unit called unit cooler is arranged inside the refrigerated warehouse (see Non-Patent Literature 1 and Non-Patent Literature 2). Hitherto, fluorocarbon-based refrigerant having a low flammability and a low toxicity has been used as the refrigerant to be used for the refrigeration cycle apparatus. In recent years, refrigerant having a low GWP, that is, a low global warming potential, has attracted attention in terms of global environmental conservation. The refrigerated warehouse includes a casing formed of heat insulating panels. Joints of the heat insulating panels are sealed, and hence an extremely high air tightness is provided. The fluorocarbon-based refrigerant containing slightly flammable refrigerant has a specific gravity larger than that of air. When the refrigerant leaks from the indoor unit, there is a fear in that the refrigerant stagnates inside the refrigerated warehouse.

[0003]

In Patent Literature 1, there is disclosed a refrigerated warehouse including a refrigeration cycle apparatus using slightly flammable refrigerant having a low GWP.

According to Patent Literature 1, when the refrigerant leaks, the leaking refrigerant is accumulated in an outdoor unit.

Citation List

Patent Literature [0004]

Patent Literature 1: Japanese Patent No. 3109500 Non-Patent Literature [0005]

Non-Patent Literature 1: Refrigerating Warehouse Japan Society of Refrigerating and Air Conditioning Engineers, page 97

Non-Patent Literature 2: Unit Cooler Catalogue Mitsubishi Electric Corporation, November 2014 Summary of Invention Technical Problem [0006]

In the refrigerated warehouse disclosed in Patent Literature 1, however, the casing is not formed of heat insulating panels. The refrigerated warehouse including the casing formed of the heat insulating panels has an extremely high airtightness, and hence is desired to more reliably discharge the refrigerant therefrom.

[0007]

The present invention has been made to solve the problem described above and has an object to provide a refrigerated warehouse including a casing formed of heat insulating panels, which is configured to easily discharge refrigerant therefrom when the refrigerant leaks.

Solution to Problem [0008]

According to one embodiment of the present invention, there is provided a refrigerated warehouse, including: a warehouse main body, which is formed of heat insulating panels, and has an introduction port for introducing outdoor air and a discharge port for discharging indoor air; an introduction lid, which is provided to the introduction port, and is configured to open and close the introduction port; a discharge lid, which is provided to the discharge port, and is configured to open and close the discharge port; a leakage detecting unit, which is provided inside the warehouse main body, and is configured to detect leakage of refrigerant; and a controller, which is configured to control the introduction lid and the discharge lid to open the introduction port and the discharge port when the leakage of the refrigerant is detected by the leakage detecting unit.

Advantageous Effects of Invention [0009]

According to one embodiment of the present invention, when the leakage of the refrigerant is detected, the controller opens the introduction port and the discharge port. Therefore, air which is introduced from the introduction port is discharged from the discharge port together with the leaking refrigerant. Thus, even from the refrigerated warehouse including the warehouse main body which is formed of the heat insulating panels, when the refrigerant leaks, the refrigerant can be easily discharged.

Brief Description of Drawings [0010] [Fig. 1] Fig. 1 is a sectional view for illustrating a refrigerated warehouse 100 according to Embodiment 1 of the present invention.

[Fig. 2] Fig. 2 is a circuit diagram for illustrating a refrigeration cycle apparatus 10 in Embodiment 1 of the present invention.

[Fig. 3] Fig. 3 is a sectional view for illustrating the refrigerated warehouse 100 according to Embodiment 1 of the present invention.

[Fig. 4] Fig. 4 is a sectional view for illustrating a refrigerated warehouse 200 according to Embodiment 2 of the present invention.

[Fig. 5] Fig. 5 is a sectional view for illustrating the refrigerated warehouse 200 according to Embodiment 2 of the present invention.

[Fig. 6] Fig. 6 is a sectional view for illustrating a refrigerated warehouse 300 according to Embodiment 3 of the present invention.

[Fig. 7] Fig. 7 is a sectional view for illustrating the refrigerated warehouse 300 according to Embodiment 3 of the present invention.

Description of Embodiments [0011]

Embodiment 1

Now, a refrigerated warehouse according to embodiments of the present invention is described with reference to the drawings. Fig. 1 is a sectional view for illustrating a refrigerated warehouse 100 according to Embodiment 1 of the present invention. The refrigerated warehouse 100 is described with reference to Fig. 1.

As illustrated in Fig. 1, the refrigerated warehouse 100 includes a warehouse main body 1, an introduction lid 32a, an introduction motor 32b, a discharge lid 31a, a discharge motor 31 b, a leakage detecting unit 41, and a controller 42. Further, a refrigeration cycle apparatus 10 is provided to the refrigerated warehouse 100.

[0012]

The warehouse main body 1 is formed of heat insulating panels 1 f, and has an introduction port 32 and a discharge port 31. The warehouse main body 1 is, for example, a casing having a cuboidal shape which forms an outer shell of the refrigerated warehouse 100. Further, a plurality of the heat insulating panels 1f are sealed at a periphery of the warehouse main body 1, and the warehouse main body 1 is, for example, a prefabricated refrigerator. The warehouse main body 1 has a door 1 e which allows entry and exit of, for example, a person 2 or packages 3. The introduction port 32 is an opening for introducing outdoor air into the refrigerated warehouse 100 and is formed, for example, in a portion of a wall surface 1b which extends from a ceiling surface 1c of the warehouse main body 1 by a distance corresponding to one third of a height of the warehouse main body 1. The introduction port 32 may be formed in the ceiling surface 1c of the warehouse main body 1. The discharge port 31 is an opening for discharging indoor air to an outside of the refrigerated warehouse 100 and is formed, for example, in a portion of the wall surface 1 b which extends from a floor surface 1 a of the warehouse main body 1 by a distance corresponding to one third of the height of the warehouse main body 1.

The discharge port 31 may be formed in the floor surface 1a of the warehouse main body 1.

[0013]

The introduction lid 32a is provided to the introduction port 32 and is configured to open and close the introduction port 32. The introduction motor 32b is provided to the introduction lid 32a and is configured to drive the introduction lid 32a to be opened and closed. The discharge lid 31a is provided to the discharge port 31 and is configured to open and close the discharge port 31. The discharge motor 31 b is provided to the discharge lid 31a and is configured to drive the discharge lid 31a to be opened and closed.

[0014]

Fig. 2 is a circuit diagram for illustrating a refrigeration cycle apparatus 10 in Embodiment 1 of the present invention. As illustrated in Fig. 2, the refrigeration cycle apparatus 10 includes a refrigerant circuit through which the refrigerant flows. The refrigerant circuit is formed of, for example, a compressor 11, an outdoor heat exchanger 12, expansion units 13, and indoor heat exchangers 14, which are connected by pipes 24. The refrigeration cycle apparatus 10 includes an outdoor unit 21 and indoor units 22. The outdoor unit 21 and the indoor units 22 are connected by the pipes 24. The pipes 24 include pipes 24a and pipes 24b. The pipes 24a are located outside the warehouse to extend from the outdoor unit 21 to the warehouse main body 1. The pipes 24b are located inside the warehouse to extend from the warehouse main body 1 to the indoor units 22. The outdoor unit 21 is installed outside the refrigerated warehouse 100. Inside the outdoor unit 21, for example, the compressor 11 and the outdoor heat exchanger 12 are installed. The indoor units 22 are installed inside the refrigerated warehouse 100. Inside each of the indoor units 22, for example, the expansion unit 13 and the indoor heat exchanger 14 are installed.

[0015]

The compressor 11 is configured to compress the refrigerant. The outdoor heat exchanger 12 is configured to exchange heat between the outdoor air and the refrigerant to condense the refrigerant. Each of the expansion units 13 is configured to expand and decompress the refrigerant. Each of the indoor heat exchangers 14 5 is configured to exchange heat between the indoor air and the refrigerant to evaporate the refrigerant. The refrigerant used for the refrigerant cycle apparatus 10 is, for example, slightly flammable refrigerant. Further, in Embodiment 1, the indoor units 22 are installed on the ceiling surface 1c inside the refrigerated warehouse 100. However, the indoor units 22 may be installed on the wall surface 1b or may be installed on the floor surface 1a. Further, in Embodiment 1, the two indoor units 22 are installed. However, the number of installed indoor units 22 may be one or may be three or more.

[0016]

Now, an operation of the refrigeration cycle apparatus 10 during a cooling operation is described. The refrigerant is sucked into the compressor 11 of the outdoor unit 21 and is compressed by the compressor 11 to be discharged in a hightemperature and high-pressure gas state. The discharged refrigerant flows into the outdoor heat exchanger 12. The refrigerant having flowed into the outdoor heat exchanger 12 exchanges heat with the outdoor air to be condensed. The condensed refrigerant flows into the expansion unit 13 of each of the indoor units 22 to be expanded and decompressed by the expansion unit 13. The decompressed refrigerant flows into the indoor heat exchanger 14. The refrigerant having flowed into the indoor heat exchanger 14 exchanges heat with the indoor air to be evaporated. At this time, the indoor air is cooled to cool an interior of the refrigerated warehouse 100. After that, the evaporated refrigerant is sucked into the compressor

11. A flow switching device may be provided in the refrigeration cycle 10. In this case, a heating operation can be carried out.

[0017]

The leakage detecting unit 41 is provided inside the warehouse main body 1 and is configured to detect leakage of the refrigerant. The leakage detecting unit 41 is provided, for example, in a space which extends from the floor surface 1a of the warehouse main body 1 by a distance corresponding to one third of the height of the warehouse main body 1. In this manner, when a specific gravity of the refrigerant is larger than a specific gravity of the indoor air, and the refrigerant is stagnates in a lower part of an internal space of the refrigerated warehouse 100, the leakage detecting unit 41 can accurately detect the leakage of the refrigerant. The leakage detecting unit 41 detects the refrigerant leaking from, for example, the indoor units 22 or the pipes 24b arranged indoors. Further, the leakage detecting unit 41 may be provided, for example, in a space which extends from the ceiling surface 1c of the warehouse main body 1 by a distance corresponding to one third of the height of the warehouse main body 1. In this manner, when the specific gravity of the refrigerant is smaller than the specific gravity of the indoor air, and the refrigerant stagnates in an upper part of the internal space of the refrigerated warehouse 100, the leakage detecting unit 41 can accurately detect the leakage of the refrigerant.

[0018]

When the leakage of the refrigerant is detected by the leakage detecting unit 41, the controller 42 controls the introduction lid 32a and the discharge lid 31a to open the introduction port 32 and the discharge port 31. The controller 42 has contacts (not shown) respectively connected to the introduction motor 32b and the discharge motor 31 b. When the leakage of the refrigerant is detected by the leakage detecting unit 41, the controller 42 closes the contacts to operate the introduction motor 32b and the discharge motor 31 b. In this manner, the introduction lid 32a and the discharge lid 31a are driven to be opened and closed to open the introduction port 32 and the discharge port 31. The introduction lid 32a and the discharge lid 31a may be driven to be opened and closed at the same time or may be driven to be opened and closed at different timings.

[0019]

Fig. 3 is a sectional view for illustrating the refrigerated warehouse 100 according to Embodiment 1 of the present invention. Next, an operation of the controller 42 is described. In the refrigerated warehouse 100, the refrigeration cycle apparatus 10 is normally in operation so that the indoor air in the refrigerated warehouse 100 is cooled by the indoor heat exchangers 14 respectively included in the indoor units 22. Further, the controller 42 opens the contacts respectively connected to the introduction motor 32b and the discharge motor 31 b to stop the introduction motor 32b and the discharge motor 31 b. Therefore, the introduction lid 32a and the discharge lid 31a are closed to shut the introduction port 32 and the discharge port 31.

[0020]

When the leakage of the refrigerant is detected by the leakage detecting unit 41 inside the refrigerated warehouse 100, the controller 42 closes the contacts respectively connected to the introduction motor 32b and the discharge motor 31 b to operate the introduction motor 32b and the discharge motor 31 b. Therefore, the introduction lid 32a and the discharge lid 31a are opened to open the introduction port 32 and the discharge port 31. At this time, the controller 42 stops the operations of the indoor units 22 and the outdoor unit 21.

[0021]

According to Embodiment 1, when the leakage of the refrigerant is detected, the controller 42 opens the introduction lid 32a and the discharge lid 31a. Therefore, as illustrated in Fig. 3, the outdoor air having been introduced from the introduction port 32 via an introduction path 71 is discharged together with leaking refrigerant 6 from the discharge port 31 via a discharge path 72. Therefore, even from the refrigerated warehouse 100 including the warehouse main body 1 formed of the heat insulating panels 1f, when the refrigerant leaks, the refrigerant can be easily discharged. Further, when the refrigerant leaks, the refrigerant can be easily discharged without requiring complicated control such as opening and closing of a plurality of valves. Further, the operations of the indoor units 22 are stopped. Therefore, the leaking refrigerant and the indoor air are not agitated. In this manner, the refrigerant can be quickly discharged to the outside of the refrigerated warehouse 100.

[0022]

In a case of a plurality of the refrigerated warehouses, each including the refrigeration cycle apparatus in which the plurality of indoor units are connected to the single outdoor unit, when the refrigerant leaks from one of the indoor units, a large amount of the refrigerant leaks in comparison to an internal volume of the refrigerated 8 warehouse. In this case, when the outdoor units have the same cooling capacity, a total volume of the refrigerated warehouses which can be cooled is the same. Specifically, the volume of the refrigerated warehouse given in a case in which the single refrigerated warehouse is cooled is larger than a volume of each of the refrigerated warehouses given in a case in which the plurality of refrigerated warehouses are cooled. Therefore, a concentration of the leaking refrigerant is higher in the plurality of refrigerated warehouses, each including the refrigeration cycle apparatus in which the plurality of indoor units are connected to the single outdoor unit, than in the refrigerated warehouse including the refrigeration cycle apparatus in which the single indoor unit is connected to the outdoor unit having the same cooling capacity.

[0023]

Now, it is assumed that a value obtained by dividing an amount of leaking refrigerant by an internal volume of a refrigerator is an indoor refrigerant concentration. An amount of refrigerant to reach a refrigerant deficiency level is the same in a case in which the single refrigerated warehouse is cooled and in a case in which the plurality of refrigerated warehouses are cooled. Further, a total volume of the refrigerated warehouse given in the case in which the single refrigerated warehouse is cooled and a total volume of the refrigerated warehouses given in the case in which the plurality of refrigerated warehouses are cooled are equal to each other. Therefore, an internal volume of each of the refrigerated warehouses is smaller in the case in which the plurality of refrigerated warehouses are cooled.

Thus, the indoor refrigerant concentration is higher in the case in which the plurality of refrigerated warehouses are cooled than in the case in which the single refrigerated warehouse is cooled.

[0024]

Hitherto, there is disclosed a technology of accumulating the refrigerant in the outdoor unit when the leaking refrigerant is detected. When the plurality of refrigerated warehouses, each including the refrigeration cycle apparatus in which the plurality of indoor units are connected to the single outdoor unit, are cooled, however, 9 time is required to detect the leaking refrigerant in each of the refrigerated warehouses. Therefore, a lower limit amount of the refrigerant for detection of the leaking refrigerant stagnates in one refrigerated warehouse to increase the concentration of the refrigerant. On the other hand, in Embodiment 1, when the leakage of the refrigerant is detected, the controller 42 opens the introduction lid 32a and the discharge lid 31a. Therefore, even in each of the refrigerated warehouses 100 in the case in which the plurality of refrigerated warehouses 100, each including the refrigerant cycle apparatus 10 in which the plurality of indoor units 22 are connected to the single outdoor unit 21, the leaking refrigerant can be discharged to the outside of the warehouse before the concentration of the leaking refrigerant increases.

[0025]

Further, the introduction port 32 is formed in the portion which extends from the ceiling surface 1c of the warehouse main body 1 by the distance corresponding to one third of the height of the warehouse main body 1, whereas the discharge port 31 is formed in the portion which extends from the floor surface 1a of the warehouse main body 1 by the distance corresponding to one third of the height of the warehouse main body 1. The interior of the refrigerated warehouse 100 is cooled by the refrigeration cycle apparatus 10. Therefore, the indoor air has a lower temperature and a larger specific gravity than the outdoor air. For example, assuming that a dry-bulb temperature is 5 degrees Celsius and a relative humidity is 50%, the specific gravity of the indoor air is 1.3 kg/m³ Assuming that the dry-bulb temperature is 25 degrees Celsius and the relative humidity is 60%, the specific gravity of the outdoor air is 1.2 kg/m³. Therefore, the indoor air has the larger specific gravity. Hence, after the introduction port 32 and the discharge port 31 are opened, the indoor air moves down to be discharged. The same amount of outdoor air as the amount of indoor air which moves downs to be discharged is introduced from the introduction port 32.

[0026]

In Embodiment 1, assuming that the dry-bulb temperature is 5 degrees Celsius 10 and the relative humidity is 50%, the specific gravity of the refrigerant is about 21.0 kg/m³. Therefore, the refrigerant stagnates in the lower part of the internal space of the refrigerated warehouse 100 due to a difference in specific gravity between the refrigerant and the indoor air. As a result, after the discharge port 31 formed in the floor surface 1 a of the warehouse main body 1 or in the portion of the wall surface 1 b which extends from the floor surface 1a by the distance corresponding to one third of the height of the warehouse main body 1 is opened, the refrigerant which stagnates on the floor surface is discharged by priority. In this manner, in Embodiment 1, the refrigerant can be more quickly discharged to the outside of the refrigerated warehouse 100.

[0027]

The refrigerated warehouse 100 further includes the introduction motor 32b and the discharge motor 31 b. The introduction motor 32b is provided to the introduction lid 32a and is configured to drive the introduction lid 32a to be opened and closed. The discharge motor 31 b is provided to the discharge lid 31 a and is configured to drive the discharge lid 31 a to be opened and closed. The controller 42 has the contacts respectively connected to the introduction motor 32b and the discharge motor 31 b. When the leakage of the refrigerant is detected by the leakage detecting unit 41, the controller 42 operates the introduction motor 32b and the discharge motor 31 b by closing the contacts. As a result, the introduction lid 32a and the discharge lid 31a are opened to open the introduction port 32 and the discharge port 31.

[0028]

At the periphery of the warehouse main body 1, the plurality of heat insulating panels 1f are sealed. In this manner, the refrigerated warehouse 100 according to Embodiment 1 is, for example, a prefabricated refrigerator having a high airtightness or other refrigerators.

[0029]

Embodiment 2.

Fig. 4 is a sectional view for illustrating a refrigerated warehouse 200 according to Embodiment 2 of the present invention. Embodiment 2 differs from Embodiment 1 in that the refrigerated warehouse 200 includes a fan 51. In Embodiment 2, the same components as those of Embodiment 1 are denoted by the same reference symbols to herein omit the description thereof, and differences from Embodiment 1 are mainly described.

[0030]

As illustrated in Fig. 4, the fan 51 is provided to the introduction port 32 formed in the warehouse main body 1. The fan 51 is mounted in such an orientation that the outdoor air is introduced from the outside of the refrigerated warehouse 200 into the refrigerated warehouse 200. During stop of the fan 51, an introduction lid 232a serves as a partition wall which separates an inside of the refrigerated warehouse 100 and an outside of the refrigerated warehouse 100 and is of pressure-driven type or of motor-driven type. The controller 42 is configured to operate the fan 51 when the leakage of the refrigerant is detected by the leakage detecting unit 41.

[0031]

Fig. 5 is a sectional view for illustrating the refrigerated warehouse 200 according to Embodiment 2 of the present invention. Next, an operation of the controller 42 is described. In the refrigerated warehouse 200, the refrigeration cycle apparatus 10 is normally in operation so that the indoor air in the refrigerated warehouse 200 is cooled by the indoor heat exchangers 14 respectively included in the indoor units 22. Further, the controller 42 opens the contacts respectively connected to the introduction motor 32b, the discharge motor 31b, and the fan 51 to stop the introduction motor 32b, the discharge motor 31 b, and the fan 51. Therefore, the introduction lid 32a and the discharge lid 31a are closed to shut the introduction port 32 and the discharge port 31.

[0032]

When the leakage of the refrigerant is detected by the leakage detecting unit inside the refrigerated warehouse 200, the controller 42 closes the contacts respectively connected to the introduction motor 32b, the discharge motor 31b, and the fan 51 to operate the introduction motor 32b, the discharge motor 31 b, and the fan 51. Therefore, the introduction lid 232a and the discharge lid 31a are opened to open the introduction port 32 and the discharge port 31. Further, the fan 41 is operated. At this time, the controller 42 stops the operations of the indoor units 22 and the outdoor unit 21.

[0033]

According to Embodiment 2, the refrigerated warehouse 200 further includes the fan 51 provided to the introduction port 32 formed in the warehouse main body 1. When the leakage of the refrigerant is detected, the controller 42 opens the introduction lid 32a and the discharge lid 31a to operate the fan 51. Further, the fan 51 is mounted in such an orientation that the outdoor air is introduced from the outside of the refrigerated warehouse 100 into the refrigerated warehouse 100. Therefore, as illustrated in Fig. 5, the outdoor air is introduced from the introduction port 32 by the fan 51 to pressurize the internal space of the refrigerated warehouse 100 at a positive pressure.

[0034]

The internal space of the warehouse is kept at a positive pressure by a static pressure generated by the fan 51 so that the refrigerant 6 which stagnates on the floor surface is discharged from the discharge port 31 via the discharge path 72. Therefore, the refrigerant can be more easily discharged. Further, the operations of the indoor units 22 are stopped. Therefore, the leaking refrigerant and the indoor air are not agitated. As a result, the refrigerant can be quickly discharged to the outside of the refrigerated warehouse 200.

[0035]

The fan 51 may be mounted in such an orientation that the indoor air is discharged from the refrigerated warehouse 200 to the outside of the refrigerated warehouse 200. When a specific gravity of the refrigerant is smaller than the specific gravity of the indoor air, and the refrigerant stagnates in an upper part of the internal space of the refrigerated warehouse 200, the outdoor air taken from the discharge port 31 turns into the indoor air under the static pressure generated by the fan 51 to exit the introduction port 32 together with the leaking refrigerant. In this case, the introduction port 32 functions as an opening for discharging the indoor air, whereas the discharge port 31 functions as an opening for introducing the outdoor air. [0036]

Further, the controller 42 may be configured to operate the fan 51 with a rotating direction of the fan 51 being reversed. When a specific gravity of the refrigerant is smaller than the specific gravity of the indoor air, and the refrigerant stagnates in the upper part of the internal space of the refrigerated warehouse 200, the outdoor air taken through the discharge port 31 is turned into the indoor air under the static pressure generated by the fan 51 to exit the introduction port 32 together with the leaking refrigerant. In this case, the introduction port 32 functions as an opening for discharging the indoor air, whereas the discharge port 31 functions as an opening for introducing the outdoor air.

[0037]

The fan 51 may be provided to the discharge port 31 formed in the warehouse main body 1. In this case, the fan 51 is mounted in such an orientation that the indoor air is discharged from the refrigerated warehouse 200 to the outside of the refrigerated warehouse 200. When a specific gravity of the refrigerant is larger than the specific gravity of the indoor air, and the refrigerant stagnates in a lower part of the internal space of the refrigerated warehouse 200, the indoor air is quickly discharged by using the static pressure generated by the fan 51 without agitating the indoor air. In this manner, by further providing the fan 51 provided to the introduction port 32 or to the discharge port 31, which are formed in the warehouse main body 1, the refrigerant can be quickly discharged to the outside of the refrigerated warehouse 200.

[0038]

Embodiment 3

Fig. 6 is a sectional view for illustrating a refrigerated warehouse 300 according to Embodiment 3 of the present invention. Embodiment 3 differs from Embodiment 2 in that a discharge lid 331a serves as an air-pressure regulating valve. In

Embodiment 3, the same parts as those of Embodiments 1 and 2 are denoted by the 14 same reference symbols to herein omit the description thereof, and differences from Embodiments 1 and 2 are mainly described.

[0039]

As illustrated in Fig. 6, the discharge lid 331a serves as the air-pressure regulating valve. The air-pressure regulating valve is configured to open the discharge port 31 when a pressure of the outdoor air and a pressure of the indoor air have a difference. When the door 1 e of the refrigerated warehouse 300 is opened and closed so that warm outdoor air enters the refrigerated warehouse 300 to be suddenly cooled, the pressure of the indoor air is lowered to make the door 1e unopenable in some cases. Further, in a case of defrosting using a heater when the refrigeration cycle apparatus 10 performs a defrosting operation, air heated with the heater circulates inside the warehouse. Then, the pressure of the indoor air suddenly increases to break or deform the door 1 e, the panels provided to the refrigerated warehouse 300, or other components due to the pressure in some cases. The air-pressure regulating valve regulates an internal air pressure in the cooing warehouse 300 to prevent the door 1e from becoming unopenable and prevent the breaking or the deformation of the door 1 e, the panels, or other components.

[0040]

Fig. 7 is a sectional view for illustrating the refrigerated warehouse 300 according to Embodiment 3 of the present invention. Next, an operation of the controller 42 is described. In the refrigerated warehouse 300, the refrigeration cycle apparatus 10 is normally in operation so that the indoor air in the refrigerated warehouse 300 is cooled by the indoor heat exchangers 14 respectively included in the indoor units 22. Further, the controller 42 opens the contacts respectively connected to the introduction motor 32b and the fan 51 to stop the introduction motor 32b and the fan 51. Therefore, the introduction lid 32a is closed to shut the introduction port 32. Further, the pressure of the outdoor air and the pressure of the indoor air are equal to each other, and hence the discharge lid 331a serving as the air-pressure regulating valve is closed to shut the discharge port 31.

[0041]

When the leakage of the refrigerant is detected by the leakage detecting unit 41 inside the refrigerated warehouse 300, the controller 42 closes the contacts respectively connected to the introduction motor 32b and the fan 51 to operate the introduction motor 32b and the fan 51. Therefore, the introduction lid 32a is opened to open the introduction port 32. Further, the fan 51 is operated. When the fan 51 is operated, the outdoor air is introduced from the introduction port 32 to pressurize the internal space of the refrigerated warehouse 300 at a positive pressure. Then, the discharge lid 331a serving as the air-pressure regulating valve is pressed to be opened by the static pressure generated by the fan 51. As a result, the discharge port 31 is opened. At this time, the controller 42 stops the operations of the indoor units 22.

[0042]

According to Embodiment 3, the opening port is formed in the warehouse main body 1. The refrigerated warehouse 300 further includes the discharge lid 331 a.

The discharge lid 331a is provided to the discharge port 31 being the opening port and is configured to open the discharge port 31 being the opening port when the pressure of the outdoor air and the pressure of the indoor air have a difference. The discharge lid 331a serves as the air-pressure regulating valve configured to open the discharge port 31 when the pressure of the outdoor air and the pressure of the indoor air have the difference. When the leakage of the refrigerant is detected, the controller 42 opens the introduction lid 32a and operates the fan 51. Further, the fan 51 is mounted in such an orientation that the outdoor air is introduced from the outside of the refrigerated warehouse 300 into the refrigerated warehouse 300. Therefore, as illustrated in Fig. 7, the outdoor air is introduced from the introduction port 32 by the fan 51 to pressurize the internal space of the refrigerated warehouse 300 at a positive pressure. Further, the discharge lid 331a serving the air-pressure regulating valve is pressed to be opened by the static pressure generated by the fan 51. As a result, the discharge port 31 is opened.

[0043]

Then, the outdoor air introduced from the introduction port 32 via the 16 introduction path 71 is discharged together with the leaking refrigerant 6 from the discharge port 31 via the discharge path 72 by using the static pressure generated by the fan 51. Therefore, the refrigerant can be more easily discharged. Further, the operations of the indoor units 22 are stopped. Therefore, the leaking refrigerant and the indoor air are not agitated. As a result, the refrigerant can be quickly discharged to the outside of the refrigerated warehouse 300.

[0044]

The fan 51 may be mounted in such an orientation that the indoor air is discharged from the refrigerated warehouse 300 to the outside of the refrigerated warehouse 300. When a specific gravity of the refrigerant is smaller than the specific gravity of the indoor air, and the refrigerant stagnates in an upper part of the internal space of the refrigerated warehouse 300, the outdoor air taken from the discharge port 31 exits the introduction port 32 together with the leaking refrigerant under the static pressure generated by the fan 51. In this case, the introduction port 32 functions as an opening for discharging the indoor air, whereas the discharge port 31 functions as an opening for introducing the outdoor air. Further, the air-pressure regulating valve may be provided independently of the discharge lid without using the discharge lid 331a therefor.

[0045]

Further, the controller 42 may be configured to operate the fan 51 with a rotating direction of the fan 51 being reversed. When a specific gravity of the refrigerant is smaller than the specific gravity of the indoor air, and the refrigerant stagnates in the upper part of the internal space of the refrigerated warehouse 300, the outdoor air taken through the discharge port 31 is turned into the indoor air under the static pressure generated by the fan 51 to exit the introduction port 32 together with the leaking refrigerant. In this case, the introduction port 32 functions as an opening for discharging the indoor air, whereas the discharge port 31 functions as an opening for introducing the outdoor air. The discharge lid 331 a serving as the airpressure regulating valve functions to open the opening for introducing the outdoor air.

[0046]

The fan 51 may be provided to the discharge port 31 formed in the warehouse main body 1, and the discharge lid 331a may serve as an air-pressure regulating valve configured to open the introduction port 32 when the pressure of the indoor air and the pressure of the outdoor air have a difference. In this case, the fan 51 is mounted in such an orientation that the indoor air is discharged from the refrigerated warehouse 300 to the outside of the refrigerated warehouse 300. When a specific gravity of the refrigerant is larger than the specific gravity of the indoor air, and the refrigerant stagnates in a lower part of the internal space of the refrigerated warehouse 300, the indoor air is quickly discharged from the discharge port 31 by using the static pressure generated by the fan 51 without agitating the indoor air. As described above, when the introduction lid 32a or the discharge lid 331a serves as the air-pressure regulating valve which opens the introduction port 32 or the discharge port 31 when the pressure of the outdoor air and the pressure of the indoor air have a difference. In this manner, the discharge lid 331a is not required to be mounted additionally.

[0047]

In the embodiments described above, the controller 42 closes the contacts respectively connected to the introduction motor 32b, the discharge motor 31b, and the fan 51. However, the contacts respectively connected to the introduction motor 32b, the discharge motor 31 b, and the fan 51 may also serve as a contact for a refrigerant leakage abnormality signal. In this manner, the contact can be used for, for example, a lighting output of a warning lamp or a remote abnormality signal alarm output.

Reference Signs List [0048] warehouse main body 1a floor surface 1b wall surface 1c ceiling surface 1e door 1f heat insulating panel 2 person 3 package 6 refrigerant 10 refrigeration cycle apparatus 11 compressor 12 outdoor heat exchanger 13 expansion unit 14 indoor heat exchanger 21 18 outdoor unit 22 indoor unit 24, 24a, 24b pipe31 discharge port31 a discharge Iid31b discharge motor 32 introduction port 32a introduction lid

32b introduction motor 41 leakage detecting unit 42 controller 51 fan 71 introduction path 72 discharge path 100 refrigerated warehouse 200 refrigerated warehouse 232a introduction lid 300 refrigerated warehouse 331a discharge lid

Claims

CLAIMS [Claim 1]

A refrigerated warehouse, comprising:

a warehouse main body, which is formed of heat insulating panels, and has an 5 introduction port for introducing outdoor air and a discharge port for discharging indoor air;

an introduction lid, which is provided to the introduction port, and is configured to open and close the introduction port;

a discharge lid, which is provided to the discharge port, and is configured to 10 open and close the discharge port;

a leakage detecting unit, which is provided inside the warehouse main body, and is configured to detect leakage of refrigerant; and a controller, which is configured to control the introduction lid and the discharge lid to open the introduction port and the discharge port when the leakage of the

15 refrigerant is detected by the leakage detecting unit.
[Claim 2]

The refrigerated warehouse of claim 1, wherein the introduction port is formed in a portion which extends from a ceiling surface of the warehouse main body by a distance corresponding to one third of a

20 height of the warehouse main body, and wherein the discharge port is formed in a portion which extends from a floor surface of the warehouse main body by a distance corresponding to one third of the height of the warehouse main body.
[Claim 3]

25 The refrigerated warehouse of claim 1 or 2, further comprising:

an introduction motor, which is provided to the introduction lid, and is configured to drive the introduction lid to be opened and closed; and a discharge motor provided to the discharge lid, which is configured to drive the discharge lid to be opened and closed, wherein the controller has contacts each connected to the introduction motor and the discharge motor, and wherein the controller is configured to operate the introduction motor and the discharge motor by closing the contacts when the leakage of the refrigerant is

5 detected by the leakage detecting unit.
[Claim 4]

The refrigerated warehouse of any one of claims 1 to 3, further comprising a fan, which is provided to the introduction port or the discharge port formed in the warehouse main body.

10 [Claim 5]

The refrigerated warehouse of any one of claims 1 to 4, wherein an opening port is formed in the warehouse main body, and wherein the refrigerated warehouse further comprises an air-pressure regulating valve, which is provided to the opening port, and is configured to open the 15 opening port when a pressure of the outdoor air and a pressure of the indoor air have a difference.

[Claim 6]

The refrigerated warehouse of any one of claims 1 to 5, wherein a plurality of the heat insulating panels are sealed at a periphery of the warehouse main body.