Cooling storage box

Abstract

To avoid a situation where a flammable atmosphere is formed by a combustible refrigerant which has leaked in a box.SOLUTION: A cooling storage box includes a combustible refrigerant discharge mechanism for discharging part of a combustible refrigerant which has leaked from a cooler 35 to the outside of a cooling box body 12. In the case where a situation continues where at least an opening / closing door 14 is not open, the concentration of the combustible refrigerant in a storage chamber R1 is gradually reduced by the combustible refrigerant discharge mechanism. In the combustible refrigerant discharge mechanism, for example, a drain port 42A of a defrosting water drain pipe 42 is disposed at an opposing position on the opposite side by sandwiching the cooler 35 with respect to a circulation fan 44, and part of the leaked combustible refrigerant is discharged to the outside of the cooling box body 12 via the defrosting water drain pipe 42.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] In recent years, in refrigeration cycle type cooling storage units that circulate a refrigerant, natural refrigerants have been used as the refrigerant as an effort to consider the global environment. Natural refrigerants are flammable refrigerants, and it is necessary to deal with the case where the flammable refrigerant leaks. The cooling storage unit disclosed in the following Patent Document 1 is configured to include a freezer compartment 1, a heat exchanger 2, a blower device 3, and a drawer door 4, with a container 5b on the drawer door 4 and a hole 7 on the bottom 6b of the container 5b. As a result, in the event that a refrigerant leak occurs from the heat exchanger 3, even if the flammable refrigerant that is heavier than air accumulates in the container 5b, it will escape downward through the hole 7 on the bottom 6b of the container 5b and accumulate on the lower side 8 of the container 5b, and can be easily discharged outside the unit when the user opens the drawer door 4. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-221143 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the refrigerated storage cabinet disclosed in Patent Document 1, if the door is not opened for a long period of time, the refrigerant concentration inside the cabinet increases, and there is a risk of a flammable atmosphere being formed. Then, if the door is opened after the flammable atmosphere has been formed, the flammable atmosphere is suddenly released outside the cabinet, which is a problem.

[0005] The present invention has been made in consideration of such circumstances, and an object of the present invention is to prevent a situation in which a flammable atmosphere is formed inside a storage compartment due to a leaked flammable refrigerant. [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; A flammable refrigerant discharge mechanism that discharges a portion of the flammable refrigerant leaking from the cooler to the outside of the cooling chamber body; Equipped with A cooling storage facility in which the concentration of flammable refrigerant in the storage chamber is gradually reduced by the flammable refrigerant discharge mechanism at least when the opening and closing door remains open for a certain period of time.

[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 a flammable refrigerant leaks from the cooler, the cold air containing the flammable refrigerant is sent to the storage chamber by the circulation fan, and the concentration of the flammable refrigerant increases in the cooling chamber body (inside the chamber). In particular, if the door is not opened by the user 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 storage chamber. According to the cooling storage disclosed in the present application, although there is a case where outside air is taken into the storage chamber by discharging a part of the flammable refrigerant to the outside of the chamber by the flammable refrigerant discharge mechanism, the concentration of the flammable refrigerant in the storage chamber can be gradually reduced, and therefore a situation in which a flammable atmosphere is formed in the storage chamber can be avoided. In other words, even if a flammable refrigerant leaks, the cooling storage disclosed in the present application can gradually reduce the concentration of the flammable refrigerant while continuing the cooling operation, so that the quality of the cooled object is not deteriorated or the deterioration of the quality can be suppressed. In the cooling storage cabinet disclosed in the present application, various configurations as described below can be used as the flammable refrigerant discharge mechanism, but a configuration in which the air inside the cabinet containing the flammable refrigerant is gradually discharged to the outside of the cabinet in small amounts so as not to significantly affect the cooling function is desirable.

[0008] In addition, the cooling storage container disclosed in the present application may be configured so that the refrigerant discharge mechanism is always in operation, or may be configured so that it operates only when the door is kept open and has an operating source. In other words, the cooling storage container disclosed in the present application can avoid the formation of a flammable atmosphere due to a flammable refrigerant without adding a new sensor to detect leakage of the flammable refrigerant.

[0009] The cooling storage unit having the above-mentioned configuration can be embodied in various forms as shown below. Note that the present invention is not limited to the following forms, and can be embodied in various forms that have been modified or improved based on the knowledge of those skilled in the art, or in a form that combines a plurality of forms.

[0010] (2) A defrost water drain pipe is provided having a drain opening in the cooler chamber and for draining water droplets from the cooler, The cooler is disposed downstream of the airflow of the circulation fan, The drain outlet is disposed at a position opposite to the circulation fan across the cooler, The flammable refrigerant discharge mechanism of the cooling storage unit described in (1) above discharges a portion of the leaked flammable refrigerant to the outside of the cooling storage unit body via the defrost water drain pipe.

[0011] In the cooling storage of this configuration, a part of the cold air sent from the cooler by the circulation fan is blown onto the drain outlet of the defrost water drain pipe. In other words, according to the cooling storage of this configuration, even if a flammable refrigerant leaks from the cooler, a part of the cold air containing the flammable refrigerant can be made to enter the defrost water drain pipe and discharged to the outside of the storage via the defrost water drain pipe, so that the concentration of the flammable refrigerant in the storage chamber can be gradually reduced and the concentration of the flammable refrigerant can be prevented from increasing.

[0012] (3) The defrost water drain pipe is arranged to extend downward from the drain outlet side along the inner surface of the outer wall panel that constitutes the outer wall of the cooling cabinet body, The defrost water drain pipe is provided with an exhaust hole, The cooling storage facility according to claim 2, wherein the exterior wall panel has an air vent formed in a position opposite the exhaust hole of the defrost water drain pipe.

[0013] In the cooling storage of this configuration, the air that has entered the defrost water drain pipe, i.e., a part of the air containing the leaked flammable refrigerant, can be discharged to the outside of the defrost water drain pipe at the intermediate portion of the defrost water drain pipe and to the outside of the storage body. For example, even if a trap is provided in the downstream portion of the defrost water drain pipe, the air containing the leaked flammable refrigerant can be reliably discharged to the outside of the storage. Note that it is preferable that the exhaust hole of the defrost water drain pipe is formed at a position where the defrost water does not easily flow and has a small size and width so that the defrost water does not leak to the outside.

[0014] (4) The cooling cabinet body includes a bottom drainage section that drains water from the bottom of the storage chamber, The bottom surface side drainage portion has a drainage trap, An exhaust hole is formed on the upper side of the drain trap, The flammable refrigerant discharge mechanism of the cooling storage unit described in (1) above discharges a portion of the leaked flammable refrigerant to the outside of the cooling storage unit body through the exhaust hole.

[0015] The flammable refrigerant is heavier than air and may accumulate near the bottom of the storage chamber. In the cooling storage chamber of this configuration, a portion of the air containing the leaked flammable refrigerant can be discharged to the outside of the chamber from the bottom side drainage section that drains the water from the bottom of the storage chamber, and the concentration of the flammable refrigerant in the storage chamber can be gradually reduced to prevent the concentration of the flammable refrigerant from becoming too high.

[0016] (5) A cap is provided to close an opening of the bottom drain portion to the storage chamber, The top surface of the cap is higher than the bottom surface of the storage chamber, The cooling storage container according to claim (4), wherein the cap has an air vent penetrating downward from the top surface side.

[0017] Depending on the user, the cooling storage unit may be used with the bottom drainage part covered with a cap. In such a case, it is necessary to ventilate the cap. In the cooling storage unit of this configuration, when the bottom drainage part is covered with a cap, it is possible to pass only the air in the storage unit without allowing the water that has fallen to the bottom of the storage unit to flow through the vent hole.

[0018] (6) The opening of the insulating box opens forward, The opening and closing door has a packing on an inner surface side which abuts against an edge of the opening of the insulating box, The cooling chamber is formed below the top surface of the insulating box and above the storage chamber, The circulation fan is configured to discharge the cold air in the cooling chamber downward along the back surface of the storage chamber, The cooling cabinet main body is configured to change the flow direction of the cold air from the cooling chamber from a direction along the back surface of the storage chamber to a direction toward the front along the bottom surface, and the cold air toward the front hits a bottom surface contact portion, which is a portion of the packing that contacts the bottom surface of the insulating box body, The flammable refrigerant discharge mechanism of the cooling storage unit described in paragraph (1) above allows a portion of the leaked flammable refrigerant to leak outside the cooling storage unit body at least from between the bottom surface of the insulated box body and the bottom surface contact portion of the gasket.

[0019] In the cooling storage of this configuration, the air sent to the cooler chamber by the circulation fan flows forward on the bottom surface of the storage chamber and is blown onto the lower end portion (bottom surface contact portion) of the packing provided on the opening and closing door. In addition, in the cooling storage of this configuration, the greater the air volume of the circulation fan, the greater the force blown onto the packing, and a small amount of air in the storage chamber can be leaked from a small gap formed between the bottom surface of the insulating box and the bottom surface contact portion of the packing. In other words, with the cooling storage of this configuration, even if a flammable refrigerant leaks from the cooler, a small amount of the flammable refrigerant can be gradually discharged to the outside of the chamber from between the insulating box and the opening and closing door, gradually reducing the concentration of the flammable refrigerant in the storage chamber.

[0020] (7) A control unit that executes a cooling operation to cool the storage chamber, The control unit of the cooling storage facility described in (6) above increases the air volume of the circulation fan to a value greater than the air volume set during the cooling operation if the opening / closing door remains open while the cooling operation is being performed.

[0021] In a cooling storage cabinet of this configuration, by increasing the air volume of the circulating fan, it is easier for air (flammable refrigerant) to be expelled from between the bottom surface of the insulated box body and the contact portion of the bottom surface of the gasket, thereby reliably gradually reducing the concentration of flammable refrigerant in the storage chamber.

[0022] (8) A cooling storage facility as described in (6) or (7), in which a concave or convex portion is formed on either the bottom surface of the insulating box body or the bottom surface contact portion of the packing.

[0023] A cooling storage cabinet of this configuration is designed to allow a small amount of air to leak between the bottom of the insulated box body and the contact part between the bottom of the gasket, thereby ensuring a gradual reduction in the concentration of flammable refrigerant in the storage chamber.

[0024] (9) A cooling storage container as described in (6) or (7), in which an air hole is formed in the bottom surface contact portion of the gasket, connecting the storage chamber with the outside of the cooling storage container body.

[0025] A cooling storage cabinet of this configuration is designed with an air vent at the bottom contact portion of the gasket to allow a small amount of air to leak out, thereby ensuring a gradual reduction in the concentration of flammable refrigerant in the storage chamber.

[0026] (10) The flammable refrigerant discharge mechanism of the cooling storage cabinet described in paragraph (1) has an intake device that draws air into the cooling storage cabinet main body as its operating source, and gradually reduces the concentration of flammable refrigerant in the storage chamber by making the pressure inside the cooling storage cabinet main body higher than the external pressure and causing the air inside the storage chamber to leak between the insulated box body and the opening and closing door.

[0027] In the cooling storage of this configuration, the pressure inside the cooling storage body is made slightly higher than atmospheric pressure, so that the amount of air leaking out from between the insulating box body and the opening and closing door can be increased. In other words, even if a flammable refrigerant leaks, the amount of flammable refrigerant discharged can be increased, and the concentration of the flammable refrigerant in the storage chamber can be steadily reduced. In addition, in the cooling storage of this configuration, the flammable refrigerant discharge mechanism may be periodically operated at a set time interval, or, as described below, the flammable refrigerant discharge mechanism may be operated when it is detected that the opening and closing door has not been opened for a long time.

[0028] (11) The flammable refrigerant discharge mechanism of the cooling storage unit described in paragraph (1) has a ventilation valve as an actuation source, and gradually reduces the concentration of flammable refrigerant in the storage chamber by replacing part of the air inside the cooling storage unit body with the outside using the ventilation valve.

[0029] A refrigerated storage facility of this configuration can replace at least a portion of the air inside the storage facility body with outside air using the ventilation valve, so that even in the event of a leak of flammable refrigerant, the concentration of flammable refrigerant inside the storage chamber can be effectively gradually reduced.

[0030] (12) The flammable refrigerant discharge mechanism of the cooling storage cabinet described in paragraph (1) has a biasing device as an actuation source that biases the opening and closing door in an opening direction, and the biasing device biases the opening and closing door to cause air in the storage chamber to leak from between the insulated box body and the opening and closing door, thereby gradually reducing the concentration of flammable refrigerant in the storage chamber.

[0031] In the cooling storage cabinet of this configuration, the biasing device can open the door slightly to allow some of the air in the storage chamber to be discharged to the outside, or loosen the contact state between the packing on the door and the insulating box body to allow the air in the storage chamber to leak out from between the insulating box body and the packing. Note that, for example, a solenoid, a motor, or the like can be used as the biasing device.

[0032] (13) A control unit that executes a cooling operation to cool the storage chamber, The cooling storage facility according to any one of claims (10) to (12), wherein the control unit drives the operating source to operate the flammable refrigerant discharge mechanism when the opening / closing door continues to be left open during the cooling operation.

[0033] The cooling storage cabinet of this configuration can be configured to activate the flammable refrigerant discharge mechanism when a door sensor detects that the door has not been opened for a set period of time or more. With the cooling storage cabinet of this configuration, it is possible to suppress the temperature rise inside the cooling storage cabinet body. Effect of the Invention

[0034] According to the present invention, it is possible to prevent a situation in which a flammable atmosphere is formed inside the container due to a flammable refrigerant leaking therefrom. [Brief description of the drawings]

[0035] [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] FIG. 11 is a cross-sectional view showing a main part of a modified example of the first flammable refrigerant discharge mechanism. [Figure 7] FIG. 11 is a side cross-sectional view showing a main part of a modified example of the first flammable refrigerant discharge mechanism. [Figure 8] FIG. 13 is a rear view showing a main part of a modified example of the first flammable refrigerant discharge mechanism. [Figure 9] FIG. 13 is a side cross-sectional view showing a main portion of a modified example of the second flammable refrigerant discharge mechanism. [Figure 10] FIG. 13 is a side cross-sectional view showing a main portion of another modified example of the second flammable refrigerant discharge mechanism. [Figure 11] FIG. 11 is a side cross-sectional view showing a modified example of the actuation source of the second flammable refrigerant discharge mechanism. [Figure 12] FIG. 11 is a side cross-sectional view showing another modified example of the actuation source of the second flammable refrigerant discharge mechanism. [Figure 13] FIG. 11 is a side cross-sectional view showing a main part of a freezer according to a second embodiment. [Figure 14] FIG. 11 is a side cross-sectional view showing a main part of a freezer according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] <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 Fr, Rr, 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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 22 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] The first flammable refrigerant mechanism and the second flammable refrigerant 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 mechanism and the second flammable refrigerant 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.

[0053] 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 mechanism and the second flammable refrigerant 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.

[0054] 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 for executing 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.

[0055] <Modification of the first flammable refrigerant discharge mechanism> In the freezer 10 of the above-mentioned embodiment 1, the first flammable refrigerant discharge mechanism is configured so that the flammable refrigerant sent into the defrost water drain pipe 42 is discharged to the outside from the lower end side of the defrost water drain pipe 42, but it is also possible to configure so that the flammable refrigerant is discharged to the outside from the middle part of the defrost water drain pipe 42. The defrost water drain pipe 42 is disposed in a portion close to the inner surface of the outer box 13A in the rear wall 13F of the heat-insulating box body 13. Then, a recess 60 is formed on the rear side of the heat insulating material 13C, and the defrost water drain pipe 42 is disposed so as to penetrate the recess 60. As a result, as shown in FIG. 6, a portion that is not covered by the heat insulating material 13C is formed in the middle part of the defrost water drain pipe 42. Also, as shown in FIG. 6 to FIG. 8, a plurality of slits (exhaust holes) 62 extending in the vertical direction are formed in the portion of the defrost water drain pipe 42 that is not covered by the heat insulating material 13C.

[0056] The slit 62 has a very small width (for example, 1 mm or less) and is formed only on the outer box 13A side (rear side) of the defrost water drain pipe 42. Incidentally, since the defrost water flows in from the cooling duct 40 arranged on the front side of the defrost water drain pipe 42, it often flows along the inner box 13B side (front side), and the defrost water is unlikely to leak from the slit 62. Then, a part of the air sent into the defrost water drain pipe 42 (air containing a flammable refrigerant in the case of refrigerant leakage) is discharged to the outside of the cooling chamber body 12 from the slit 62 and the vent hole 64A formed in the cover member 64 covering the recess 60 of the heat insulating material 13C. Therefore, according to the freezer of this modified example, even if a trap is provided in the downstream part of the defrost water drain pipe 42, a part of the air containing the leaked flammable refrigerant can be reliably discharged to the outside of the freezer.

[0057] <Modification of second flammable refrigerant discharge mechanism> Next, some modified examples of the second flammable refrigerant discharge mechanism will be described. In the freezer 10 of the above-mentioned embodiment 1, the cooling performance is prioritized and the mechanism is designed to make it difficult for the refrigerant to leak between the bottom surface 13G of the heat-insulating box 13 and the bottom surface contact portion 50A of the packing 50, but the mechanism may be designed to make the refrigerant leak more easily than the freezer 10 of the above-mentioned embodiment 1. For example, as shown in FIG. 9, a groove 70 extending vertically may be formed in the bottom surface 13G of the heat-insulating box 13 to generate a gap between the bottom surface 13G of the heat-insulating box 13 and the bottom surface contact portion 50A of the packing 50, or as shown in FIG. 10, a through hole (exhaust hole) 72 penetrating from the storage chamber R1 side to the outside of the freezer may be formed in the bottom surface contact portion 50A (specifically, the cylindrical portion 51A) of the packing 50. In addition, the configuration for creating a gap between the bottom surface 13G of the insulating box 13 and the bottom surface contact portion 50A of the packing 50 is not limited to the groove 70, but may be a configuration in which a convex portion is provided on the bottom surface 13G, or a configuration in which a concave portion or a convex portion is provided on the bottom surface contact portion 50A of the packing 50.

[0058] The second flammable refrigerant discharge mechanism can be configured so that during normal cooling operation, almost no air leaks from between the bottom surface 13G of the insulating box 13 and the bottom surface contact portion 50A of the packing 50, and only when the air volume of the internal fan 44 is increased, air leaks from between the bottom surface 13G of the insulating box 13 and the bottom surface contact portion 50A of the packing 50. In other words, in this configuration, the internal fan 44 can be considered to function as the operating source of the second flammable refrigerant discharge mechanism.

[0059] The configuration for operating the second flammable refrigerant discharge mechanism by the operating source may, for example, include a biasing device for biasing the door 14 in the opening direction, and the biasing device may bias the door 14 to cause air in the storage chamber R1 to leak from between the heat-insulating box 13 and the door 14. As shown in FIG. 11, the biasing device may be a solenoid 76. Specifically, the solenoid 76 is fixed to the front surface of the bottom surface portion 13G of the heat-insulating box 13, and a piston 76A is adapted to abut against the inner surface of the door 14 in the closed state. When the solenoid 76 is energized, the piston 76A is biased forward, biasing the door 14 forward. That is, by weakening the attraction force of the magnet 52 of the packing 50 or by separating the bottom contact portion 50A of the packing 50 from the insulating box 13, the air in the storage chamber R1 can be leaked from between the bottom portion 13G of the insulating box 13 and the bottom contact portion 50A of the packing 50. Note that the biasing device may be a motor provided in the hinge portion of the opening / closing door 14 to apply a rotational force to the opening / closing door 14 in the opening direction.

[0060] A freezer 80 having a configuration in which the second flammable refrigerant discharge mechanism is operated by an operating source may be configured as shown in Fig. 12. This freezer 80 is provided with an air pump (suction device) 82 that takes in air into the cooling chamber main body 12 as an operating source of the second flammable refrigerant discharge mechanism. The air pump 82 is disposed in the machine room R2, and is capable of sending air into the storage chamber R1 through a suction hole 84 formed in the ceiling wall 13D of the heat-insulating box 13. By sending air into the storage chamber R1, the air pump 82 can make the pressure inside the cooling chamber main body 12 higher than the external pressure (atmospheric pressure), and cause the air inside the storage chamber R1 to leak out from between the heat-insulating box 13 and the packing 50 of the opening / closing door 14.

[0061] <Embodiment 2> Next, a freezer 90 equipped with a flammable refrigerant discharge mechanism having a configuration different from the two flammable refrigerant discharge mechanisms of the above-mentioned embodiment 1 will be described with reference to Fig. 13. In this freezer 90, the cooling chamber body 12 is equipped with a bottom surface side drainage section 92 that drains water from the bottom surface of the storage chamber R1, and the flammable refrigerant discharge mechanism is provided in this bottom surface side drainage section 92. The bottom surface of the storage chamber R1 is gently inclined toward the front, and a drain port 93 of the bottom surface side drainage section 92 is opened and formed at the end of the bottom surface.

[0062] A cylindrical drain body 94 is fitted into the drain port 93. A cap 95 is detachably attached to the upper end of the drain body 94. A joint 96 having a trap 96A is connected to the lower end of the drain body 94. This trap 96A prevents odors from entering the interior of the refrigerator.

[0063] An exhaust hole 97 is formed in a connection portion 96B to the drain body 94, which is an upward extending portion of the joint 96, i.e., above the trap 96A. The flammable refrigerant is heavier than air, and since the airflow caused by the internal fan 44 flows forward on the bottom surface, it may accumulate at the front side of the bottom surface of the storage chamber R1. In the freezer 90 of this embodiment, the accumulated flammable refrigerant can be guided into the bottom-side drainage portion 92 and discharged to the outside of the freezer through the exhaust hole 97.

[0064] The cap 95 may be used by a user with the drain outlet 93 blocked. The cap 95 is provided with a knob 95A for the user to grip, and recesses 95B are formed on both sides of the knob 95A, and ventilation holes 95C are formed in the recesses 95B, which penetrate in the vertical direction. In addition, when the cap 95 is fitted into the drain body 94, the top surface of the cap 95 is higher than the bottom surface of the storage chamber R1. This allows the cap 95 to allow only the air in the storage chamber R1 to pass through the ventilation holes 95C, without allowing the drain in the storage chamber R1 to flow through the ventilation holes 95C.

[0065] As described above, in the case of a leak of flammable refrigerant, the freezer 90 of this embodiment, regardless of whether or not the cap 95 is present, can discharge some of the air containing the leaked flammable refrigerant to the outside of the freezer, 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.

[0066] <Embodiment 3> A freezer 100 having a flammable refrigerant discharge mechanism of another configuration will be described with reference to FIG. 14. The freezer 100 of this embodiment is provided with a ventilation valve 102 on the ceiling wall 13D of the heat-insulating box body 13. The freezer 100 of this embodiment can exchange part of the air in the cooling box body 12 with the outside by the ventilation valve 102, and can gradually reduce the concentration of the flammable refrigerant in the storage room R1. This ventilation valve 102 functions as an operating source of the flammable refrigerant discharge mechanism, and can be configured to operate when the opening and closing door 14 is not opened for a set time or more, as in the freezer 10 of the first embodiment, or can be configured to operate periodically at a set time interval.

[0067] <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.

[0068] The freezer 10 of the above-mentioned embodiment 1 is described as having two flammable refrigerant discharge mechanisms, but it may have only one of them, or may have a configuration in which a modified flammable refrigerant discharge mechanism or a flammable refrigerant discharge mechanism of another embodiment is combined.

[0069] The flammable refrigerant discharge mechanism of the above embodiment can be naturally adopted in a refrigerator, and depending on the type of the flammable refrigerant discharge mechanism, can also be adopted in a tabletop refrigerator-freezer. Furthermore, it can also be adopted in a refrigerator-freezer showcase or a prefabricated refrigerator-freezer. [Explanation of symbols]

[0070] 10...freezer [cooling storage], 12...cooling storage body, 13...insulating box body, 13D...ceiling wall [top surface], 13F...back wall, 13G...bottom surface, 14...opening door, 16...opening, R1...storage chamber, R3...cooling chamber, 18...cooling device, 24...control device [control section], 35...cooler, 36...refrigerant pipe, 42...defrosting water drain pipe, 42A...drain, 44...interior fan, 50...packing, 50A... bottom contact portion, 62... slit (exhaust hole), 64A... vent hole, 70... groove (recess), 72... through hole (vent hole), 76... solenoid (actuating device), 80... freezer, 82... air pump (suction device), 90... freezer, 92... bottom drain portion, 95... cap, 95C... vent hole, 96A... trap, 97... exhaust hole, 100... freezer, 102... ventilation valve

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; A flammable refrigerant discharge mechanism that discharges a portion of the flammable refrigerant leaking from the cooler to the outside of the cooling chamber body; Equipped with A cooling storage facility in which the concentration of flammable refrigerant in the storage chamber is gradually reduced by the flammable refrigerant discharge mechanism at least when the opening and closing door remains open for a certain period of time.

2. a defrost water drain pipe having a drain port opening into the cooler chamber and for discharging water droplets from the cooler; The cooler is disposed downstream of the airflow of the circulation fan, The drain outlet is disposed at a position opposite to the circulation fan across the cooler, 2. The cooling storage cabinet according to claim 1, wherein the flammable refrigerant discharge mechanism discharges a portion of the leaked flammable refrigerant to the outside of the cooling storage cabinet body through the defrost water drain pipe.

3. The defrost water drain pipe is disposed so as to extend downward from the drain outlet side along an inner surface of an outer wall panel that constitutes an outer wall of the cooling cabinet body, The defrost water drain pipe is provided with an exhaust hole, 3. The cooling storage facility according to claim 2, wherein the exterior wall panel is formed with an air vent at a position opposite the exhaust hole of the defrost water drain pipe.

4. The cooling cabinet main body includes a bottom drainage section that drains water from the bottom of the storage chamber, The bottom surface side drainage portion has a drainage trap, An exhaust hole is formed on the upper side of the drain trap, 2. The cooling storage container according to claim 1, wherein the flammable refrigerant discharge mechanism discharges a portion of the leaked flammable refrigerant to the outside of the cooling storage container body through the exhaust hole.

5. a cap for closing an opening of the bottom drain portion to the storage chamber; The top surface of the cap is higher than the bottom surface of the storage chamber, 5. The cooling storage container according to claim 4, wherein the cap is formed with an air hole passing through from a top surface side downward.

6. The opening of the insulating box opens forward, The opening and closing door has a packing on an inner surface side which abuts against an edge of the opening of the insulating box, The cooling chamber is formed below the top surface of the insulating box and above the storage chamber, The circulation fan is configured to discharge the cold air in the cooling chamber downward along the back surface of the storage chamber, The cooling cabinet main body is configured to change the flow direction of the cold air from the cooling chamber from a direction along the back surface of the storage chamber to a direction toward the front along the bottom surface, and the cold air toward the front hits a bottom surface contact portion, which is a portion of the packing that contacts the bottom surface of the insulating box body, The cooling storage cabinet according to claim 1, wherein the flammable refrigerant discharge mechanism allows a portion of the leaked flammable refrigerant to leak outside the cooling storage cabinet body at least from between the bottom surface of the insulated box body and the bottom surface contact portion of the gasket.

7. A control unit that executes a cooling operation to cool the storage chamber, The cooling storage facility according to claim 6, wherein the control unit increases the airflow of the circulation fan to a value greater than the airflow set during the cooling operation when the opening and closing door remains open for a long period of time while the cooling operation is being performed.

8. 8. The cooling storage facility according to claim 6, wherein a recess or a protrusion is formed on either the bottom surface of the heat-insulating box or the bottom surface contact portion of the packing.

9. 8. The cooling storage container according to claim 6, wherein a vent hole is formed in the bottom surface contact portion of the packing, the vent hole communicating the storage chamber with the outside of the cooling storage body.

10. The flammable refrigerant discharge mechanism of the cooling storage cabinet described in claim 1 has an intake device that draws air into the cooling storage cabinet main body as an operating source, and gradually reduces the concentration of flammable refrigerant in the storage chamber by making the pressure inside the cooling storage cabinet main body higher than the external pressure and causing air in the storage chamber to leak between the insulated box body and the opening and closing door.

11. The cooling storage cabinet described in claim 1, wherein the flammable refrigerant discharge mechanism has a ventilation valve as an actuation source, and gradually reduces the concentration of flammable refrigerant in the storage chamber by replacing a portion of the air in the cooling storage cabinet body with the outside using the ventilation valve.

12. The flammable refrigerant discharge mechanism of claim 1 has a biasing device as an actuation source that biases the opening and closing door in an opening direction, and the biasing device biases the opening and closing door to cause air in the storage chamber to leak from between the insulated box body and the opening and closing door, thereby gradually reducing the concentration of flammable refrigerant in the storage chamber.

13. A control unit that executes a cooling operation to cool the storage chamber, The cooling storage facility according to any one of claims 10 to 12, wherein the control unit drives the operating source to operate the flammable refrigerant discharge mechanism when the opening and closing door continues to be left open while the cooling operation is being performed.

Images