Refrigerator

Abstract

To provide a refrigerator which is configured to address coolant leakage at all times during cooling operation such that sensors and the like are not required and thus increase in cost can be suppressed, and which can maintain both a cooling function and safety even when the coolant leaks from a cooler.SOLUTION: The present invention includes: a refrigerator body 12 configured of a heat insulative box 13 and an open / close door 14, inside of which a storage R1 for storing a cooling object and a cooler chamber R3 for storing a cooler 35 for cooling the storage R1 are provided; a freezing-cycle-type cooling device 18 having the cooler 35, in which a combustible coolant circulates; a circulation fan 44 for circulating air between the storage R1 and the cooler chamber R3; and an air quality adjustment device 60 for adjusting the component of air inside the refrigerator body 12. The air quality adjustment device 60 lowers an oxygen concentration of the air inside the refrigerator body 12.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a cooling storage facility. [Background technology]

[0002] In recent years, natural refrigerants have been used as refrigerants in refrigeration cycle-type cold storage units that circulate a refrigerant, as an effort to be environmentally friendly. Natural refrigerants are flammable refrigerants, and it is necessary to deal with the case where the flammable refrigerant leaks. The cold storage unit (refrigeration device) disclosed in the following Patent Document 1 is provided with multiple refrigerant sensors so that refrigerant leakage inside the unit can be accurately detected, and is characterized by the positions at which the refrigerant sensors are arranged. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6137264 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional cooling storage units using a flammable refrigerant, when a refrigerant leak occurs, the unit is often configured to respond to the refrigerant leak. For example, as in the cooling storage unit disclosed in the above Patent Document 1, a refrigerant sensor must be installed, which increases costs. In addition, in the cooling storage unit disclosed in the above Patent Document 1, when a refrigerant leak is detected by the refrigerant sensor, measures such as sounding an alarm or venting the inside of the unit are taken. However, when the concentration of the flammable refrigerant increases, there is a risk that the flammable refrigerant will ignite, so it is difficult to perform normal cooling operation of a cooling storage unit that has an ignition source such as a defrosting heater. Therefore, when a refrigerant leak occurs, the cooling function is often stopped, which causes a problem of a deterioration in the quality of the cooled object when a refrigerant leak occurs.

[0005] The present invention has been made in consideration of such circumstances, and its objective is to provide a refrigerated storage facility that has a configuration that constantly responds to refrigerant leakage during cooling operation, thereby eliminating the need for sensors and preventing costs from increasing, and that can ensure both cooling function and safety even if refrigerant leakage occurs from the cooler. [Means for solving the problem]

[0006] In order to solve the above problems, the cooling storage facility disclosed in the present application has the following configuration. (1) A cooling cabinet body including an insulating box having an opening and an opening / closing door for opening and closing the opening, and having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; An air quality adjustment device that adjusts the components of the air in the cooling cabinet body; Equipped with A cooling storage cabinet in which the air quality adjustment device reduces the oxygen concentration in the air inside the cooling storage cabinet main body.

[0007] The cooling storage disclosed in the present application is premised on the use of a flammable refrigerant as the refrigerant for the refrigeration cycle type cooling device. Since the inside of the insulated box is a sealed space, if the flammable refrigerant leaks from the cooler, the cold air containing the flammable refrigerant is sent to the storage room by the circulation fan, and the concentration of the flammable refrigerant increases in the cooling room body (inside the storage room). In particular, if the user does not open the door for a long time, the concentration of the flammable refrigerant continues to increase, and there is a risk of a flammable atmosphere being formed in the cooling room body. The cooling storage of this configuration is configured to make the cooling room body into a low-oxygen state by the air quality adjustment device during normal cooling operation. In other words, the cooling storage of this configuration can prevent oxidation of the cooled object such as food materials by making the storage room into a low-oxygen state, and even if a flammable refrigerant leaks, the flammable refrigerant will not ignite in the storage room because the oxygen concentration is low, and it is possible to continue the cooling operation.

[0008] In the cooling storage facility having the above-mentioned configuration, the following aspects are possible. (2) the air quality control device is a nitrogen separation device that separates nitrogen; A cooling storage unit as described in paragraph (1) above, in which the nitrogen separation device separates only nitrogen from the air in the cooling storage unit body and returns the separated nitrogen to the cooling storage unit body, thereby reducing the oxygen concentration in the cooling storage unit body.

[0009] A cooling storage facility of this configuration is configured to create a hypoxic state by creating an excess of nitrogen inside the cooling storage body.

[0010] (3) the air quality control device is an oxygen separation device that separates oxygen; A cooling storage unit as described in paragraph (1) above, in which the oxygen separation device separates oxygen from the air in the cooling storage unit body and returns the oxygen-free air into the cooling storage unit body, thereby reducing the oxygen concentration in the cooling storage unit body.

[0011] A cooling storage cabinet of this configuration can almost completely eliminate oxygen from within the main body of the cooling cabinet, and can reliably prevent ignition of flammable refrigerant within the cabinet.

[0012] In order to solve the above problems, the cooling storage facility disclosed in the present application has the following configuration. (4) A cooling cabinet body including an insulating box having an opening and an opening / closing door for opening and closing the opening, and having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; An air quality adjustment device that adjusts the components of the air in the cooling cabinet body; Equipped with the air quality conditioner is a hydrocarbon separation device; This cooling storage unit reduces the concentration of flammable refrigerant in the air within the main body of the cooling unit by separating hydrocarbons from the air within the main body of the cooling unit using the air quality adjustment device and returning the air from which the hydrocarbons have been removed back into the main body of the cooling unit at least when a flammable refrigerant leaks from the cooler.

[0013] Natural refrigerants that are widely used in cooling storage units are hydrocarbon refrigerants such as isobutane, propane, etc. With a cooling storage unit having this configuration, even if a refrigerant leak occurs in the cooler, it is possible to prevent the concentration of flammable refrigerant in the cooling unit from increasing.

[0014] Furthermore, in order to solve the above problems, the cooling storage facility disclosed in the present application has the following configuration. (5) A cooling cabinet body including an insulating box having an opening and an opening / closing door for opening and closing the opening, and having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; A refrigerant adsorbent provided in the cooling chamber body and capable of adsorbing a flammable refrigerant; A cooling storage facility equipped with:

[0015] In the case of a refrigerant leak in the cooler, this type of cooling storage unit can prevent the concentration of flammable refrigerant in the main body of the cooling unit from increasing by adsorbing the flammable refrigerant with activated carbon or natural rubber, which will be described later. However, in order to deal with the problem using only this "refrigerant adsorbent," the refrigerant adsorbent needs to be large, so it is desirable to use it in combination with other countermeasures.

[0016] In the cooling storage facility having the above-mentioned configuration, the following aspects are possible. (6) A cooling storage cabinet as described in (5) above, which is provided with a flammable refrigerant discharge mechanism that discharges a portion of the flammable refrigerant to the outside of the cooling storage cabinet body by leaking the air within the cooling storage cabinet body to the outside of the cooling storage cabinet body, and is configured to gradually reduce the concentration of the flammable refrigerant in the storage chamber.

[0017] In the cooling storage of this configuration, the flammable refrigerant discharge mechanism is preferably configured to leak air from inside the storage from areas that contain a large amount of flammable refrigerant or areas where flammable refrigerant is likely to accumulate. According to the cooling storage of this configuration, the air inside the cooling storage body can be replaced little by little during cooling operation, so that even if a refrigerant leak occurs in the cooler, the concentration of flammable refrigerant inside the cooling storage body can be effectively prevented from increasing due to the synergistic effect with the above-mentioned refrigerant adsorbent. Incidentally, the flammable refrigerant discharge mechanism increases the air volume of the circulation fan, making it easier to discharge the air inside the cooling storage body, and the concentration of flammable refrigerant in the storage chamber can be more effectively gradually reduced.

[0018] (7) The cooling storage facility according to claim 5 or 6, wherein the refrigerant adsorbent is activated carbon.

[0019] A cooling storage cabinet with this configuration can provide an odor-preventing function using activated carbon during normal cooling operation, and in the event of a refrigerant leak in the cooler, it can adsorb flammable refrigerant, preventing the concentration of flammable refrigerant in the cabinet body from increasing.

[0020] (8) A cooling storage unit as described in (5) or (6), wherein the refrigerant adsorbent is an interior exposed member molded from natural rubber and exposed to the inside of the cooling storage unit body.

[0021] Natural rubber has the property of adsorbing liquefied petroleum gas (LPG), and can adsorb natural refrigerants such as isobutane, propane, etc., which are classified as liquefied petroleum gas. In a cooling storage unit with this configuration, examples of the exposed interior members include a slat member laid on the bottom surface of the cooling storage unit body and a door packing provided on the opening and closing door, and a cooling storage unit with a configuration that can handle leakage of flammable refrigerants can be realized simply by changing the materials of the members required for the current configuration.

[0022] Furthermore, in order to solve the above problems, the cooling storage facility disclosed in the present application has the following configuration. (9) A cooling cabinet body including an insulating box having an opening and an opening / closing door for opening and closing the opening, and having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; A combustion device provided in the cooling chamber body for combusting the flammable refrigerant leaked from the cooling device at a concentration below the lower explosion limit; A cooling storage facility equipped with

[0023] In the case of a leak of a flammable refrigerant, the cooling storage of this configuration can prevent the concentration of the flammable refrigerant in the storage chamber from increasing by burning the flammable refrigerant with the combustion device before the concentration of the flammable refrigerant becomes high. Although the combustion device may be provided exclusively for burning the flammable refrigerant, as will be described in detail later, if the flammable refrigerant is burned using an ignition source provided in the equipment required for normal cooling operation, an increase in costs can be suppressed.

[0024] In the cooling storage facility having the above-mentioned configuration, the following aspects are possible. (10) The combustion device includes an ignition source and a cover member that covers the periphery of the ignition source and has a plurality of ventilation holes; The cooling storage facility according to claim 9, wherein the inner dimensions of the plurality of vent holes are smaller than the quenching distance of the flammable refrigerant.

[0025] In a cooling storage container of this configuration, even if the flammable refrigerant comes into contact with an ignition source inside the cover member and burns, the vent holes in the cover member are smaller than the extinguishing distance, so the combustion does not spread outside the cover member. Therefore, with a cooling storage container of this configuration, the flammable refrigerant can be reliably burned little by little, and an increase in the concentration of the flammable refrigerant in the storage chamber can be reliably prevented.

[0026] (11) A cooling storage facility according to claim 9 or 10, wherein the combustion device is a plasma deodorizing device that performs deodorization by plasma discharge.

[0027] A cooling storage facility of this configuration uses the plasma discharge of the plasma deodorizing device as the ignition source for the combustion device, so there is no need to install a new combustion device, and costs can be reduced.

[0028] (12) The cooling storage facility according to claim 9 or 10, wherein the combustion device is a defrosting heater provided in the cooler to defrost the cooler.

[0029] A cooling storage facility of this configuration uses the filament of the defrost heater as the ignition source for the combustion device, so there is no need to install a new combustion device, and costs can be reduced. Effect of the Invention

[0030] According to the present invention, a cooling storage facility can be provided that is configured to constantly deal with refrigerant leakage during cooling operation, thereby eliminating the need for sensors and preventing costs from increasing, and that can ensure both cooling function and safety even if refrigerant leakage occurs from the cooler. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a perspective view of a freezer according to a first embodiment of the present invention; [Diagram 2] Side cross-sectional view of a freezer [Diagram 3] Block diagram of the control device (control unit) [Figure 4] FIG. 2 is a plan view of the cooling chamber, showing a main part of the first flammable refrigerant discharge mechanism. [Diagram 5] FIG. 13 is a side cross-sectional view showing a main part of a second flammable refrigerant discharge mechanism. [Figure 6] A side cross-sectional view showing an air quality adjustment device [Figure 7] FIG. 11 is a side cross-sectional view showing a modified example of the air quality adjustment device. [Figure 8] FIG. 11 is a side cross-sectional view showing another modified example of the air quality adjusting device. [Figure 9] FIG. 11 is a side cross-sectional view of a freezer according to a second embodiment. [Figure 10] FIG. 11 is a side cross-sectional view showing a main part of a freezer according to a third embodiment. [Figure 11] FIG. 1 is an enlarged cross-sectional view showing a refrigerant combustion section of a defrost heater, which is a combustion device. [Figure 12] FIG. 11 is a side cross-sectional view showing a modified example of the combustion device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] <Embodiment 1> A cooling storage cabinet 10 according to a first embodiment of the present invention will be described with reference to Figs. 1 to 5. As shown in Fig. 1, the cooling storage cabinet 10 according to this embodiment is a four-door freezer for commercial use, mainly used in kitchens of restaurants and the like. Hereinafter, it may be referred to as a freezer 10. Note that in some of the drawings, the symbols F, B, L, R, U, and D are used to indicate directions, and respectively represent the near side (front side), far side (rear side), left side, right side, upper side, and lower side when the cooling storage cabinet 10 is viewed from the front.

[0033] As shown in FIG. 1 and FIG. 2, the freezer 10 of this embodiment is mainly composed of a cooling chamber body 12 having a generally rectangular parallelepiped shape elongated in the vertical direction. The cooling chamber body 12 is composed of an insulated box body 13 that opens forward and an insulated opening / closing door 14. The insulated box body 13 is formed by foaming and filling a space between an outer box 13A and an inner box 13B with an insulating material 13C. The inner box 13B is provided with a cross-shaped front frame 15. This divides the opening of the inner box 13B into upper, lower, left and right, and the insulated box body 13 has four openings 16 on the front side. The insulated box body 13 is provided with four insulated opening / closing doors 14 that open and close the four openings 16. Most of the interior of the cooling chamber body 12 is a storage room R1.

[0034] As shown in FIG. 2, a machine room R2 with an open top is provided on the cooling cabinet main body 12. The machine room R2 houses a part of the cooling device 18, an electrical equipment box 20, an operation box 22 (see FIG. 1), and the like. A user of the freezer 10 can operate an operation unit 22A of the operation box 22 to perform various operations such as setting a target temperature inside the freezer. The electrical equipment box 20 houses a control device (control unit) 24 (see FIG. 3) that controls the freezer 10. The control device 24 is mainly a computer having a CPU, ROM, and RAM, and is connected to various devices of the cooling device 18, and controls the connected devices by executing various programs stored in the ROM. In addition, a door sensor 25 that detects the opening and closing of the opening and closing door 14 and a timer 26 that measures the current time are also connected to the control device 24. Incidentally, the door sensor 25 is not limited to a door switch, and may be one that detects the open state using a temperature rise curve of an in-cabinet thermistor.

[0035] The cooling device 18 is attached to a heat-insulating unit base 30 and is unitized. The unit base 30 is formed to be slightly larger than the opening 13E formed in the ceiling wall 13D of the cooling box body 12, and is disposed on the ceiling wall 13D so as to close the opening 13E. The cooling device 18 is configured to include a compressor 32, a condenser 33, a condenser fan 34, a cooler 35, etc.

[0036] The compressor 32, the condenser 33, and the cooler 35 are connected by a refrigerant pipe 36, and form a known refrigeration cycle (refrigeration circuit) by circulating the refrigerant. The compressor 32 uses a motor as a power source to draw in and compress refrigerant gas, and discharges the high-temperature, high-pressure refrigerant gas. The condenser 33 cools and liquefies the refrigerant gas compressed by the compressor 32 by blowing air from a condenser fan 34. The cooler 35 reduces the pressure of the refrigerant liquid from the condenser 33 using an expansion valve and then vaporizes it, thereby cooling the air passing through the cooler 35 by the heat of vaporization. The refrigerant gas from the cooler 35 is returned to the compressor 32.

[0037] The cooler 35 is attached to the underside of the unit base 30 and is housed in a cooler room R3 that is configured by the ceiling (ceiling wall 13D and unit base 30) and a cooling duct 40 that will be described later. The cooling duct 40 also serves to separate the storage room R1 from the cooler room R3.

[0038] The above-mentioned refrigerant pipe 36 penetrates the unit base 30 and connects the compressor 32 and the condenser 33 in the machine room R2 to the cooler 35 in the cooler room R3. In this embodiment, natural refrigerants such as isobutane and propane are used as the refrigerant in consideration of the global environment. These natural refrigerants are flammable and have a higher specific gravity than air. For example, if the refrigerant pipe 36 has a corroded portion or a portion with a thin wall thickness, the portion may crack due to the vibration of the compressor 32 or stress caused by the flow of the refrigerant, causing the refrigerant to leak.

[0039] As described above, the refrigerant circulates between the machine room R2 and the cooler room R3, and refrigerant leakage may occur in either the machine room R2 or the cooler room R3. However, if refrigerant leakage occurs from the cooler 35 in the cooler room R3, the inside of the cooling cabinet body 12 (hereinafter, sometimes simply referred to as the "inside of the cabinet") is an enclosed space, and there is a risk that the concentration of the flammable refrigerant will increase inside the cabinet, resulting in the formation of a flammable atmosphere. If a flammable atmosphere is formed inside the cooling cabinet body 12, there is a problem that the flammable atmosphere will be released to the outside of the cabinet all at once when the opening and closing door 14 is opened.

[0040] Therefore, the freezer 10 of this embodiment is characterized by a configuration that deals with refrigerant leakage from the cooler 35. The freezer 10 of this embodiment is equipped with a flammable refrigerant discharge mechanism that discharges a portion of the flammable refrigerant leaking from the cooler 35 to the outside of the refrigerator body 12, and is configured to gradually reduce the concentration of the flammable refrigerant in the storage chamber R1 by the flammable refrigerant discharge mechanism. The flammable refrigerant discharge mechanism in the freezer 10 of this embodiment will be described in detail below.

[0041] In this embodiment, one of the flammable refrigerant discharge mechanisms is provided in the cooler chamber R3, and the cooling duct 40 forming the cooler chamber R3 will be described in detail. The cooling duct 40 forms the cooler chamber R3 between itself and the ceiling, and also covers the cooler 35 from below and functions as a drain pan for receiving defrost water, which is water obtained when frost adhering to the cooler 35 melts. As shown in Figs. 2 and 4, the cooling duct 40 has a substantially flat bottom wall 40A inclined downward toward the rear side, side walls 40B rising upward from the left and right edges of the bottom wall 40A, and a rear wall 40C rising slightly upward from the rear edge of the bottom wall 40A.

[0042] As shown in FIG. 4, a suction port 40D for sucking air from the storage chamber R1 into the cooler chamber R3 is formed in the front part of the bottom wall 40A. The rear wall 40C is spaced forward from the rear wall 13F of the heat-insulating box 13, and an air outlet 40E is formed between the rear wall 40C and the rear wall 13F of the heat-insulating box 13. A drain groove 40F having a U-shaped cross section and extending from the center in the left-right direction toward the rear side is integrally formed in the rear wall 40C. A defrost water drain pipe 42 is provided inside the rear wall 13F of the heat-insulating box 13, and the drain groove 40F has a rear end inserted from the drain port 42A of the defrost water drain pipe 42 and connected to the defrost water drain pipe 42. That is, the defrost water received by the cooling duct 40 is discharged from the drain groove 40F to the outside of the storage via the defrost water drain pipe 42.

[0043] An internal fan (circulation fan) 44 is attached above the intake port 40D of the cooling duct 40. When the internal fan 44 is operated, air in the storage chamber R1 is sucked into the cooler chamber R3 from the intake port 40D, and the sucked air is cooled by the cooler 35 and blown out from the outlet 40E into the storage chamber R1. In other words, the cooling duct 40 constitutes a path for circulating air between the storage chamber R1 and the cooler chamber R3.

[0044] The drain port 42A of the defrost water drain pipe 42 is located on the opposite side of the cooler 35, downstream of the airflow of the internal fan 44, with respect to the internal fan 44, and opens toward the cooler 35. With this configuration, in the freezer 10 of this embodiment, a part of the cold air sent from the cooler 35 by the internal fan 44 is blown to the drain port 42A of the defrost water drain pipe 42. That is, even if a flammable refrigerant leaks from the cooler 35, the freezer 10 of this embodiment can send a part of the cold air containing the flammable refrigerant to the defrost water drain pipe 42. Since the flammable refrigerant is heavier than air, it moves downward in the defrost water drain pipe 42 and is discharged from the lower end of the defrost water drain pipe 42 to the outside via the drain pipe 46 or the like. Therefore, the freezer 10 of this embodiment is configured such that one of the flammable refrigerant discharge mechanisms gradually discharges a portion of the leaked flammable refrigerant in small amounts to the outside of the cooling cabinet main body 12 via the defrost water drain pipe 42, thereby gradually reducing the concentration of the flammable refrigerant in the storage chamber R1 and preventing the concentration of the flammable refrigerant from becoming too high.

[0045] The freezer 10 of this embodiment is provided with a second flammable refrigerant discharge mechanism, which is another flammable refrigerant discharge mechanism, in addition to the first flammable refrigerant discharge mechanism, which is a flammable refrigerant discharge mechanism configured to discharge the flammable refrigerant through the defrost water drain pipe 42. The second flammable refrigerant discharge mechanism is configured to leak a part of the leaked flammable refrigerant to the outside of the cooling chamber body 12 from between the heat-insulating box body 13 and the opening and closing door 14. In the freezer 10 of this embodiment, as shown in FIG. 2, the internal fan 44 discharges cold air downward from the cooler chamber R3 along the back surface of the storage chamber R1, more specifically, along the back wall 13F of the heat-insulating box body 13. The cooling chamber body 12 is configured to change the flow direction of the cold air discharged from the cooler chamber R3 from the direction along the back surface of the storage chamber R1 to the direction toward the front along the bottom surface portion 13G, and the cold air toward the front hits the packing 50 of the opening and closing door 14.

[0046] Specifically, as shown in FIG. 5, the opening / closing door 14 has a protrusion 14A formed on the inner surface thereof in the closed state, which is inserted into the heat-insulating box body 13 (storage chamber R1), and a packing 50 is fixed along the outer periphery of the protrusion 14A. The packing 50 is made of a rubber packing body 51 and a magnet 52 housed in the packing body 51, and when the opening / closing door 14 is in the closed state, the packing body 50 comes into contact with the front surface of the heat-insulating box body 13 by the magnet 52. The packing body 51 is generally cylindrical and has a cylindrical portion 51A that is elastically deformable so as to be crushed when the opening / closing door 14 is in the closed state, and a fin portion 51B that extends from the cylindrical portion 51A toward the protrusion 14A. The fin portion 51B comes into contact with the outer periphery of the protrusion 14A with its tip curved backward.

[0047] With this configuration, the cold air moving forward along the bottom surface 13G of the heat insulating box 13 enters between the bottom surface 13G and the protruding portion 14A of the opening and closing door 14, and is blown onto the bottom surface contact portion 50A, which is the portion of the packing 50 that contacts the bottom surface 13G of the heat insulating box 13. More specifically, the cold air is blown onto the fin portion 51B of the bottom surface contact portion 50A of the packing 50. As a result, for example, the pressure between the bottom surface 13G and the protruding portion of the opening and closing door 14 increases, causing a small amount of air in the storage chamber R1 to leak from a small gap between the bottom surface 13G of the heat insulating box 13 and the bottom surface contact portion 50A of the packing 50. In other words, if a flammable refrigerant leaks, the air containing the flammable refrigerant can be gradually discharged to the outside of the cooling box body 12 in small amounts.

[0048] The first flammable refrigerant discharge mechanism and the second flammable refrigerant discharge mechanism are configured to operate at all times, and it is not preferable for the cold air to leak too much outside the cooling chamber body 12. Therefore, the amount of air leaking from the cooling chamber body 12 by the first flammable refrigerant discharge mechanism and the second flammable refrigerant discharge mechanism is usually set to be small. In addition, in the freezer 10 of this embodiment, even if a flammable refrigerant leaks from the cooler 35, if the opening and closing door 14 is frequently opened and closed, the concentration of the flammable refrigerant in the cooling chamber body 12 is unlikely to increase, and a flammable atmosphere is unlikely to be formed. On the other hand, if the opening and closing door 14 is not opened for a set time or more, the concentration of the flammable refrigerant in the cooling chamber body 12 is likely to increase.

[0049] Therefore, in the freezer 10 of this embodiment, when the cooling operation is being performed by the cooling operation execution unit 24A of the control device 24, if the door sensor 25 does not detect that the door is open for a set time or more, a flammable refrigerant discharge promotion control is performed, which is a control to increase the amount of air leaking from the cooling chamber body 12 by the first flammable refrigerant discharge mechanism and the second flammable refrigerant discharge mechanism. In the freezer 10 of this embodiment, the flammable refrigerant discharge promotion unit 24B of the control device 24 that performs this control increases the air volume of the internal fan 44 to be larger than the air volume set by the cooling operation, thereby increasing the amount of air that enters the defrost water drain pipe 42 in the first flammable refrigerant discharge mechanism and increasing the amount of air that leaks from between the heat-insulating box 13 and the packing 50 in the second flammable refrigerant discharge mechanism, thereby increasing the amount of flammable refrigerant discharged in the event of a flammable refrigerant leak.

[0050] In addition, it is desirable to check in advance the speed at which the flammable refrigerant leaks according to the air volume of the internal fan 44, and set the above-mentioned set time (the time during which the open state is not detected) and the time to execute the flammable refrigerant discharge promotion control based on the results of the check and the internal volume of the cooling cabinet main body 12, etc.

[0051] Furthermore, the freezer 10 of this embodiment is provided with a nitrogen separation device 60 that separates nitrogen from air as an air quality adjustment device that adjusts the components of the air in the cooling chamber main body 12. As shown in Figs. 1 and 6, the nitrogen separation device 60 is housed in the machine room R2, takes in air in the storage chamber R1 from an air intake 62 formed in the ceiling wall 13D, separates nitrogen from the air, and returns the separated nitrogen to the storage chamber R1 from an exhaust vent 64. That is, in the freezer 10 of this embodiment, during normal cooling operation, the inside of the cooling chamber main body 12 is made into a nitrogen excess state by the nitrogen separation device 60, and the oxygen concentration is reduced.

[0052] Therefore, the freezer 10 of this embodiment can prevent oxidation of cooled items such as food ingredients by creating a low-oxygen state in the storage chamber R1, and even if a flammable refrigerant leaks, the low oxygen concentration prevents the flammable refrigerant from igniting inside the cooling chamber main body 12, making it possible to continue cooling operation.

[0053] With the above-mentioned configuration, the freezer 10 of this embodiment constantly replaces the air in the cooling chamber body 12 by two types of flammable refrigerant discharge mechanisms, and the nitrogen separation device 60 keeps the air in the cooling chamber body 12 in a low-oxygen state, so that even if a flammable refrigerant leaks from the cooler 35, it is possible to avoid a situation in which the flammable refrigerant ignites inside or outside the cooling chamber body 12. In other words, even if a flammable refrigerant leaks from the cooler 35, the freezer 10 of this embodiment continues the cooling operation, preventing a decrease in the quality (freshness) of the cooled object in the storage chamber R1, while ensuring safety.

[0054] <Modification of the Air Quality Adjustment Device> In the freezer 10 of the first embodiment, the air quality adjustment device that adjusts the components of the air in the cooling chamber main body 12 is the nitrogen separation device 60, but as shown in Fig. 7, it can also be an oxygen separation device 66. This oxygen separation device 66 is housed in the machine room R2, takes in air in the storage chamber R1 from the intake port 62 formed in the ceiling wall 13D, separates oxygen from the air, and releases the separated oxygen to the outside, while returning the air from which oxygen has been removed to the storage chamber R1 from the exhaust port 64. In other words, in the freezer of this modified example, the oxygen concentration in the cooling chamber main body 12 is reduced by the oxygen separation device 66 during normal cooling operation, and the same effect as in the above embodiment can be obtained.

[0055] The air quality adjustment device may be a hydrocarbon separation device 68 as shown in FIG. 8. This hydrocarbon separation device 68 is housed in the machine room R2, takes in air in the storage room R1 from an intake port 62 formed in the ceiling wall 13D, separates hydrocarbons from the air, and releases the separated hydrocarbons to the outside while returning the air from which the hydrocarbons have been removed to the storage room R1 from an exhaust port 64. The flammable refrigerants, isobutane and propane, employed in the cooling storage disclosed in the present application are hydrocarbon-based refrigerants. In other words, the freezer of this modified example can prevent the concentration of the flammable refrigerant in the cooling storage body 12 from increasing even if a refrigerant leak occurs in the cooler 35.

[0056] <Embodiment 2> Next, a freezer 80 of the second embodiment will be described with reference to Fig. 9. The freezer 80 of the second embodiment is provided with a first flammable refrigerant discharge mechanism and a second flammable refrigerant discharge mechanism, similar to the freezer 10 of the first embodiment, and is capable of constantly replacing the air in the cooling chamber body 12 by leaking out a small amount at a time. In addition, the freezer 80 of the second embodiment is provided with a refrigerant adsorbent capable of adsorbing the flammable refrigerant in the cooling chamber body 12.

[0057] In the cooling chamber R3, specifically, activated carbon 82 having an odor prevention function is provided downstream (rear side) of the cooling device 35. When a refrigerant leak occurs in the cooling device 35, the activated carbon 82 functions as a refrigerant adsorbent. A slat 84 is laid on the bottom surface 13G of the heat-insulating box 13. The slat 84 is made of natural rubber. Furthermore, the packing 50 (specifically, the packing body 51) of the opening and closing door 14 is also made of natural rubber. Natural rubber has a property of adsorbing liquefied petroleum gas (LPG), and can adsorb natural refrigerants such as isobutane and propane, which are classified as liquefied petroleum gas, that is, flammable refrigerants used in the cooling storage disclosed in the present application, and the slat 84 and the packing 50 also function as refrigerant adsorbents.

[0058] In the freezer 80 of this embodiment, even if a flammable refrigerant leaks from the cooler 35, the first flammable refrigerant discharge mechanism and the second flammable refrigerant discharge mechanism allow the air in the cooling chamber body 12 to leak out in small amounts, thereby discharging the flammable refrigerant to the outside of the cooling chamber body 12, but the flammable refrigerant remaining in the cooling chamber body 12 can still be adsorbed by the refrigerant adsorbent. Therefore, the freezer 80 of this embodiment can effectively prevent the concentration of the flammable refrigerant in the cooling chamber body 12 from increasing. Note that, in the freezer 80 of this embodiment, the presence of the flammable refrigerant discharge mechanism allows the volume of the refrigerant adsorbent (activated carbon 82) to be smaller than when refrigerant leakage is handled only by the refrigerant adsorbent.

[0059] In addition, while both activated carbon 82 and the interior exposed members made of natural rubber (grips 84 and packing 50) are used as the refrigerant adsorbent, only one of them may be used. In the case of a configuration that employs only the interior exposed members made of natural rubber, a cooling storage unit that is configured to be able to deal with the leakage of flammable refrigerant can be realized simply by changing the materials of the previously required members.

[0060] <Embodiment 3> Next, a freezer 90 according to a third embodiment will be described with reference to Fig. 10 and Fig. 11. The freezer 90 according to the third embodiment is equipped with a combustion device that burns the flammable refrigerant leaked from the cooler 35 in the refrigerator body 12 at a concentration below the lower explosion limit.

[0061] As shown in Fig. 10, a freezer 90 of this embodiment is provided with a defrost heater 92 for defrosting the cooler 35, and the defrost heater 92 has a refrigerant combustion section 94 that functions as the combustion device. Specifically, the defrost heater 92 is composed of a filament 95 and a cover member 96 that covers the filament 95. However, a portion 96a of the cover member 96 that corresponds to the refrigerant combustion section 94 is made of a metal mesh, and has a plurality of ventilation holes 97, as shown in Fig. 11. That is, a portion of the cool air passing through the cooler chamber R3 passes through the cover member 96a of the refrigerant combustion section 94.

[0062] In the event that a flammable refrigerant leaks from the cooler 35, when the defrost heater 92 is operating, the flammable refrigerant contained in the air passing through the refrigerant combustion section 94 comes into contact with the filament 95 and burns. The above-mentioned ventilation hole 97 is configured so that the inner dimension L is smaller than the quenching distance of the flammable refrigerant, and the combustion does not spread outside the cover member 96a. Therefore, according to the freezer 90 of this embodiment, even if a flammable refrigerant leaks from the cooler 35, the flammable refrigerant can be reliably burned little by little at a concentration of the lower explosion limit, and an increase in the concentration of the flammable refrigerant in the storage chamber R1 can be reliably prevented.

[0063] <Modifications of Combustion Device> In the freezer 90 of the third embodiment, the combustion device uses the defrost heater 92, but is not limited to this. For example, as shown in Fig. 12, it is also possible to provide a plasma deodorization device 100 that performs deodorization by plasma discharge inside the refrigerator body 12, and burn a flammable refrigerant inside the plasma deodorization device 100 using plasma.

[0064] As described above, the third embodiment and its modified examples are configured to use another device installed in the freezer as the combustion device, and therefore there is no need to install a new combustion device, and costs can be reduced. On the other hand, the combustion device can be provided exclusively for burning the flammable refrigerant. In that case, the combustion device can be provided in a location where the flammable refrigerant is likely to accumulate, and the concentration of the flammable refrigerant in the storage chamber R1 can be effectively reduced.

[0065] <Other embodiments> The present invention is not limited to the above-described embodiment, and can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. For example, the following embodiments are also included within the technical scope of the present invention.

[0066] The freezer 10 of the above-mentioned first embodiment is provided with a flammable refrigerant discharge mechanism in addition to the air quality adjustment device, but the flammable refrigerant discharge mechanism is not essential.

[0067] The refrigerant adsorbent in the freezer 80 of the second embodiment can be combined with the air quality adjustment device in the freezer 10 of the first embodiment, and can also be combined with the combustion device of the third embodiment.

[0068] The air quality control device, the refrigerant adsorbent, and the combustion device provided in the freezer of the above embodiment can be naturally adopted in a refrigerator, and can also be adopted in a table-type freezer refrigerator. Furthermore, they can also be adopted in a freezer refrigerator showcase and a prefabricated freezer refrigerator. [Explanation of symbols]

[0069] 10...freezer (cooling storage), 12...cooling body, 13...insulating box, 14...opening door, 16...opening, R1...storage chamber, R3...cooler chamber, 18...cooling device, 35...cooler, 36...refrigerant pipe, 44...interior fan (circulation fan), 50...packing (exposed interior member, refrigerant adsorbent), 60...nitrogen separation device (air quality adjustment device), 66...oxygen separation device (air quality adjustment device), 68...hydrocarbon separation device (air quality adjustment device), 80...freezer, 82...activated carbon, 84...slats (exposed interior member, refrigerant adsorbent), 90...freezer, 92...defrost heater (combustion device), 94...refrigerant combustion section, 95...filament (ignition source), 96...cover member, 97...ventilation hole, 100...plasma deodorization device (combustion device)

Claims

1. A cooling box body including an insulating box having an opening and an opening / closing door for opening and closing the opening, the cooling box body having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; An air quality adjustment device that adjusts the components of the air in the cooling cabinet body; Equipped with A cooling storage cabinet in which the air quality adjustment device reduces the oxygen concentration in the air inside the cooling storage cabinet main body.

2. the air quality control device is a nitrogen separation device that separates nitrogen; The cooling storage unit according to claim 1, wherein the nitrogen separation device separates only nitrogen from the air in the cooling storage unit body and returns the separated nitrogen to the cooling storage unit body, thereby reducing the oxygen concentration in the cooling storage unit body.

3. the air quality conditioning device is an oxygen separation device that separates oxygen; The cooling storage unit according to claim 1, wherein the oxygen concentration in the cooling storage unit is reduced by separating oxygen from the air in the cooling storage unit body using the oxygen separation device and returning the oxygen-free air into the cooling storage unit body.

4. A cooling box body including an insulating box having an opening and an opening / closing door for opening and closing the opening, the cooling box body having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; An air quality adjustment device that adjusts the components of the air in the cooling cabinet body; Equipped with the air quality conditioner is a hydrocarbon separation device; This cooling storage unit reduces the concentration of flammable refrigerant in the air within the main body of the cooling unit by separating hydrocarbons from the air within the main body of the cooling unit using the air quality adjustment device and returning the air from which the hydrocarbons have been removed back into the main body of the cooling unit at least when a flammable refrigerant leaks from the cooler.

5. A cooling box body including an insulating box having an opening and an opening / closing door for opening and closing the opening, the cooling box body having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; A refrigerant adsorbent provided in the cooling chamber body and capable of adsorbing a flammable refrigerant; A cooling storage facility equipped with:

6. The cooling storage cabinet described in claim 5 is provided with a flammable refrigerant discharge mechanism that discharges a portion of the flammable refrigerant to the outside of the cooling storage cabinet body by leaking air within the cooling storage cabinet body to the outside of the cooling storage cabinet body, and is configured to gradually reduce the concentration of the flammable refrigerant in the storage chamber.

7. 7. The cooling storage facility according to claim 5, wherein the refrigerant adsorbent is activated carbon.

8. 7. The cooling storage container according to claim 5, wherein the refrigerant adsorbent is an interior exposed member formed from natural rubber and exposed to the inside of the cooling container body.

9. A cooling box body including an insulating box having an opening and an opening / closing door for opening and closing the opening, the cooling box body having a storage chamber for storing an object to be cooled and a cooler chamber for accommodating a cooler for cooling the storage chamber; a refrigeration cycle type cooling device including the cooler and in which a flammable refrigerant circulates; a circulation fan that circulates air between the storage chamber and the cooling chamber; A combustion device provided in the cooling chamber body for combusting the flammable refrigerant leaked from the cooling device at a concentration below the lower explosion limit; A cooling storage facility equipped with

10. The combustion device includes an ignition source and a cover member that covers the periphery of the ignition source and has a plurality of ventilation holes. The cooling storage facility according to claim 9, wherein the inner dimensions of the plurality of vent holes are smaller than the quenching distance of the flammable refrigerant.

11. 11. The cooling storage facility according to claim 9, wherein the combustion device is a plasma deodorizing device that performs deodorization by plasma discharge.

12. 11. The cooling storage facility according to claim 9, wherein the combustion device is a defrosting heater provided in the cooler for defrosting the cooler.

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