JP3188083B2 - Cold storage - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a heat-insulating outer box having an inner box having good thermal conductivity provided at a distance from the outer box, and circulating cool air between the two boxes to indirectly insulate the outer box. The present invention relates to a low-temperature storage that cools a storage room in an inner box by cooling.

[0002]

2. Description of the Related Art For example, in Japanese Utility Model Laid-Open Publication No. Sho 60-93882, a heat conductive inner box is provided inside a heat insulating outer box at intervals, and a refrigerator compartment is formed inside the inner box. Circulating cool air in the space formed between the inner box and the outer box, cooling the inner box to cool the refrigerator compartment, and evaporator of a refrigerator for creating cool air and a fan for circulating cool air. There is disclosed a refrigerator in which a refrigerator is indirectly cooled by placing a refrigerator in a cool air circulation space between an inner box and an outer box.

[0003]

In the above-mentioned conventional technique, for example, when the temperature in the refrigerator is gradually decreased over a long period of time, the temperature of the cool air from the evaporator is directly changed. Since the air flows into the cool air circulation space, a change in the cool air temperature immediately enters the refrigerator compartment via the inner box and the temperature inside the refrigerator compartment becomes unstable. In addition, the defrosting operation of the evaporator is performed during the cooling operation. During this defrosting operation, the frost can be melted by stopping the operation of the fan and heating the evaporator.However, the temperature around the evaporator rises due to the heating of the evaporator, and especially the upper part of the cool air circulation space. As the temperature rises, the temperature of the refrigerator compartment also rises. As a result, there arises a problem that, for example, the refrigerator compartment cannot be maintained at a predetermined temperature.

An object of the present invention is to provide a low-temperature storage for keeping the temperature of a storage space at a predetermined temperature while minimizing the influence of a defrosting operation of an evaporator.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heat-insulating outer box having a top wall, a bottom wall, and a side wall, and a space inside the outer box. A top wall, a bottom wall, and a side wall, which are arranged in a cool air circulation space formed between the outer box and the inner box, and a heat conductive inner box forming a storage room therein. A first blower, a heat-insulating partition plate provided at a distance from the side wall of the inner box, a cooling space separated from the cool air circulation space by the partition plate, and an upper part in the cooling space. A cooling unit composed of a cooler and a second blower disposed therein, a cool air outward path formed in a partition plate and sending cool air from a cooling space to a cool air circulation space between the inner box side wall and the partition plate, and a cold air outward path. A third blower provided and a cool air circulating space provided between the inner box bottom wall and the outer box provided below the cool air outward path to the cooling space. And a duct that forms a return cold air return, one end of the duct is in contact with the other end to the inner box side wall is to provide a cold chamber extending into the cooling space.

[0006]

[0007]

[0008]

[0009]

[0010]

According to the present invention, the cool air circulation space is divided into a cool air blow-out side and a cool air suction side by a duct, so that a short cycle of cool air discharged from the cool air forward path and flowing directly to the cool air return path can be avoided. Further, the duct extends into the cooling space, and it is possible to avoid a short cycle of the cool air in which the cool air flowing into the cool space from the cool air return path flows directly to the cool air outward path.

[0011]

[0012]

[0013]

[0014]

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Reference numeral 1 denotes a low-temperature storage such as a prefabricated refrigerator, in which an inner box 3 made of a metallic heat conductor is housed and arranged inside the heat-insulating outer box 2 with a space therebetween. A certain partition panel 4 is provided. A closed storage room 10 is formed in the inner box 3, and an upper circulation space is provided around the storage room 10, that is, in a space surrounded by the inner box 3, the outer box 2 and the partition panel 4. 11A, bottom circulation space 1
1B, front and rear side circulation spaces 11C and 11D, and left and right side circulation spaces 11E and 11F are formed as a cool air circulation space 11. The outer box 2 is formed in a box shape by combining a plurality of heat insulating panels having a convex portion or a concave portion at a connection portion with an adjacent panel, and has a top wall 2A, a bottom wall 2B, front and rear side walls 2C, 2D, and left and right. It is composed of side walls 2E and 2F. The inner box 3 includes a ceiling panel 3A as a ceiling panel and a bottom wall 3A.
B, front and rear side walls 3C and 3D, and left and right side walls 3E and 3F.

The top wall 3A, the bottom wall 3B, the front and rear side walls, and the left and right side walls 3E and 3F are each formed of a panel made of, for example, a stainless steel plate. The ceiling wall 3A is placed and fixed on the inclined upper edge of the front and rear side walls.
Further, the top wall 3A is gradually inclined left and right with the center at the top, so that the water droplets attached to the top wall 3A do not directly fall downward but flow along the inner surfaces of the left and right side walls 3E and 3F. ing. On the front wall 2D of the outer box 2, there are provided an article doorway 7 for taking in and out of stored articles, and an insulated door 8 having a glass window 8A for closing the article doorway 7 so as to be openable and closable and for closing the storage room 10. Have been.

A first blower 12 for circulating cool air is provided in the cool air circulation space 11 at the left end of the outer box 2 toward the top wall 2A. The first blower 12 is a fan 13
And a fan motor 14. In addition, an auxiliary heater H, which is a heating device, is mounted in the cool air circulation space 11 substantially at the center of the top wall 2A.

Reference numeral 15 denotes a cooling space separated from the cool air circulation space 11 by the partition panel 4. Above the cooling space 15, first and second cooling units 16 and 17 mounted side by side on the ceiling wall 2A are provided. Is provided. Each of the cooling units 16 and 17 includes a cooler 18 typified by an evaporator constituting a part of a refrigeration cycle, and second blowers 21 and 22 including a fan 19 and a fan motor 20. Further, a partition plate 23 is provided between the first cooling unit 16 and the second cooling unit 17. The partition plate 23 is suspended from the top wall 3A and extends below the first and second cooling units 16 and 17, the upper end abuts on the top wall 2A, and the left end abuts on the partition panel 4.

Reference numeral 24 denotes a cool air forward path formed at the lower portion of the partition panel 4. The cool air forward path 24 includes a third blower 27 for discharging cool air, comprising a fan 25 and a fan motor 26.
Is provided. The cool air outward path 24 communicates with the right circulation space 11F. Reference numeral 28 denotes a cool air return path formed below the cool air outward path 24, and the cool air return path 28 is formed by a duct 29. The end of the duct 29 on the side of the cool air circulation path 11 abuts on the right side wall 3F of the inner box 3, and the cool air return path 28 communicates with the bottom circulation space 11B. Reference numeral 30 denotes a multi-stage shelf mounted on the upper wall of the duct 29.
The cold storage material 31 is provided in each stage of 0.

Reference numeral 32 denotes a relief valve provided on the right side wall 2F on the cooling space 15 side to adjust the pressure in the cooling space 15.
An outdoor unit 33 is provided outside the low-temperature storage 1 and forms a refrigeration cycle together with the cooler 17 of the cooling unit 16.
34 is a relief valve provided on the rear wall D side of the cool air circulation space 11 to adjust the pressure in the cool air circulation space 11, 35 and 36 are interior lights provided in the storage room 10 and the cooling space 15, respectively. 37 is a front wall 2C of the outer box 2 on the cooling space 15 side.
The doorway used for inspection etc. formed in the doorway, 38 is the doorway 3
7 is a heat insulating door that closes openably and closably.

Reference numeral 39 denotes a temperature detector provided in the storage room 10, and reference numeral 40 denotes a control box mounted on the outer surface of the front wall C of the outer box 2. The control box 40 receives a signal from the temperature detector 39, and based on the temperature in the storage room 10, the cooling capacity of the cooling units 16 and 17, the defrosting operation, the rotation speed of the first and third blowers 11 and 27, The energization of the auxiliary heater H is controlled.

Hereinafter, the cooling of the low-temperature storage 1 configured as described above will be described.

The temperature of the object to be cooled in the storage room 10 is, for example, 1
When the temperature is decreased by 1 deg at a time, a cooling program is set in the control box 40 in advance. When the first and second cooling units 16 and 17 are operated, the temperature in the storage room 10 is higher than the set temperature, so that the first and second cooling units 16 and 17 are operated by the signal from the control box 40 based on the temperature detected by the temperature detector 38. , The second cooling unit 16,
17 is operated, and the air in the cooling space 10 is
1 and is cooled by each cooler 18 and then blown out as indicated by an arrow. The cool air blown out from the cooling units 16 and 17 is sucked by the third blower 27 provided at the lower part of the partition panel 4 and flows into the cool air circulation space 11 through the cool air outward path 24. Then, the cool air is drawn by the first blower 12, and as shown by an arrow in FIG.
F flows upward, and flows through the upper circulation space 11A from right to left. A part of the cool air flowing out of the cool air passage 24 is the first cool air.
The air is drawn by the blower 12, and flows obliquely upward through the front circulation space 11C and the rear circulation space 11D.

The cool air sucked into the first blower 12 as described above is discharged from the first blower 12, flows downward through the left circulation space 11E as indicated by the arrow in FIG. 1, and further flows into the lower circulation space 11B. From left to right toward the cold air return path 28. A part of the cool air discharged from the first blower 12 flows obliquely downward toward the cool air return path 28 through the front circulation space 11C and the rear circulation space 11D.

By this cooling air circulation, the upper and lower front and rear left and right walls 3
A to 3F are cooled, and the inside of the storage room 10 is indirectly cooled by radiant heat from each wall surface. Therefore, the entire inner box 3 can be efficiently cooled. And the cold air return route 28
The cold air that has flowed into is cooled by the first and second cooling units 16 and 17, cooled, discharged, and cooled.

When the inside of the storage room 10 is cooled as described above, the control box 37 operates to compare the set temperature at each time with the detected temperature, which is the temperature in the storage room 10, and to control each cooler. Control the cooling capacity of 18
The number of rotations of the first blower 12 and the third blower 27 is controlled. For example, when the difference between the detected temperature and the set temperature increases when the set temperature decreases by 1 deg, the cooling capacity of each cooler 18 increases and the first blower 12
And the rotation speed of the second blower 27 increases, and the cooling air circulation space 1
In 1, the cool air whose temperature has further decreased circulates, the flow rate of the circulating cool air increases, and the temperature of the storage room 10 decreases to the set temperature in a short time. After that, when controlling the cooling capacity and controlling the rotation speeds of the first and second blowers 12 and 27, when the detected temperature becomes lower than the set temperature, the control box 37 operates to operate each of the coolers. 16, 17
Cooling capacity of the first and third blowers 1
The number of rotations of 2, 27 is reduced, and the cooling capacity of the storage room 10 by the cool air flowing through the cool air circulation path 11 is reduced. For example, if the detected temperature is lower than the set temperature by a predetermined temperature or more (for example, 0.5 ° C.) even if the cooling capacity is reduced after the cooling capacity is rapidly increased, the auxiliary heater 14 is controlled by the control box 37. Is supplied to the auxiliary heater 14, the auxiliary heater 14 generates heat, and the cool air whose temperature has risen circulates in the cool air circulation space 11, and the temperature in the storage room 10 rises. Thereafter, similarly, each of the coolers 16, 1, based on the temperature in the storage room 10.
7 and the rotation speeds of the first and second blowers 12 and 27 are controlled, and the temperature in the storage room 10 gradually decreases.

As described above, the first and second cooling units 1
6 and 17 are provided in a cooling space 15 partitioned by the cool air circulation space 11 and the partition panel 4, and the cool air discharged from each cooler 18 passes through the cooling space 15 and flows from the cool air outward path 24 to the cool air circulation space 11. In addition, it is possible to prevent the influence of the cold air temperature from directly affecting the inner box, and particularly to minimize the hunting of the temperature in the storage room 10 when the cooling capacity changes, and to gradually change the temperature for a long time. Even when control is performed, the temperature can be stably changed.

Further, the number of rotations of the first blower 12 in the cool air circulation space 11, the amount of heating of the heater H, and the number of rotations of the third blower 27 in the cool air forward path 24 are controlled based on the temperature in the storage room 10. When the user opens the heat-insulating door 8 for checking stored items, etc., the temperature in the storage room 10 rises rapidly and the difference between the set temperature and the detected temperature becomes large. 11 to increase the cooling air circulation speed,
, The temperature inside the storage room 10 can be brought to the set temperature in a short time, and when the temperature inside the storage room 10 becomes lower than the set temperature, the heater H The inside of the storage room 10 can be heated via the inner box 3 by the circulation of the cool air whose temperature has been increased by heating.
The temperature in the storage room 10 can be further stabilized.

The distal end of the duct 29 on the side of the cool air circulation space 11 abuts on the right side wall 3F of the inner box 3, and the right side circulation space 1
1F is divided by a duct 29 into a cool air outlet side and a cool air suction side, so that a short cycle of cold air in which cool air discharged from the cool air forward path 24 flows directly to the cool air return path 28 can be avoided. The cold air flowing into the cooling space 15 from the cool air return path 28 and flowing directly to the cool air outward path 24 can be prevented from being short-circuited, and as a result, the cooling efficiency of the low-temperature storage 1 can be improved.

Further, when the cooler 18 of the first cooling unit 16 starts the defrosting operation while the cooling operation of the storage room 10 is performed, the second cooling unit 17 continues the cooling operation. . At this time, the cooler 18 of the first cooling unit 16 is heated by the defrosting operation, and even when the ambient temperature of the first cooling unit 16 rises, the cool air whose temperature has risen increases from the partition plate 23 to the first cooler 16. Maintained in the upper space on the cooling unit 16 side, the temperature rise of the cool air flowing from the cooling space 15 to the cool air circulation space 11 during the defrosting operation is slightly suppressed, and the temperature change in the storage room 10 during the defrosting operation is slightly reduced. Can be suppressed. As a result, the temperature in the storage room 11 can be further stabilized.

Further, a plurality of cold storage materials 31 are provided in the cooling space 15.
Are provided in the cool air between the cool air return path 28 and the cool air outward path 24, so that each cool storage material 31 is cooled by the cool air flowing through the cooling space 15.
Then, when the cooling capacity is reduced due to the defrosting operation of the first cooling unit 16 or the second cooling unit 17, the cool air flowing into the cooling space 15 is cooled by the cold storage material 31, so that the cooling capacity can be supplemented. As a result, the cool air can be circulated stably to the cool air circulation space 11 even during defrosting, and the cooling operation of the low-temperature storage 1 can be further stabilized.

The present invention is not limited to the above embodiment, but can be modified without departing from the gist of the present invention.

[0034]

The present invention is a low-temperature storage constructed as described above, and the cool air circulation space is divided into a cool air blow-out side and a cool air suction side by a duct, and cool air discharged from the cool air forward path is directly returned to the cool air return path. A short cycle of flowing cold air can be avoided, and the duct extends into the cooling space,
This makes it possible to avoid a short cycle of the cool air flowing from the cool air return path into the cooling space directly to the cool air forward path.

[0035]

[0036]

[0037]

[0038]

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a part of a low-temperature refrigerator.

FIG. 2 is a plan sectional view of a low-temperature storage.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low temperature storage 2 Outer box 3 Inner box 3A Top wall 3E Side wall 3F Side wall 4 Partition panel 10 Storage room 11 Cold air circulation space 12 Second blower 15 Cooling space 16 First cooling unit 18 Cooler 21 Second blower 23 Partition Plate 24 Cold air forward path 27 Third blower 28 Cold air return path 31 Cold storage material 40 Control box H Heater

Continuation of front page (56) References JP-A-5-141840 (JP, A) JP-A-5-18652 (JP, A) JP-A-4-371780 (JP, A) JP-A-59-137774 (JP) , A) Japanese Utility Model Showa 60-93882 (JP, U) Japanese Utility Model Application Hei 4-50376 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 13/00 101 F25D 17/08 301 F25D 17/08 311

Claims (1)

(57) [Claims] 1. A heat insulating outer box comprising a top wall, a bottom wall, and a side wall, and a top wall disposed inside the outer box with a space therebetween.
A heat-conductive inner box having a bottom wall and a side wall and forming a storage chamber therein; and a first blower disposed in a cool air circulation space formed between the outer box and the inner box. And a heat insulating partition plate provided at a distance from the side wall of the inner box, a cooling space separated from the cool air circulation space by the partition plate, and a cooling device disposed at an upper portion in the cooling space. A cooling unit composed of a vessel and a second blower, a cool air forward path formed in the partition plate for sending cool air from the cooling space to a cool air circulation space between the inner box side wall and the partition plate, and a third cool air passage provided in the cool air forward path. A blower, and a duct provided below the cool air outward path and forming a cool air return path for returning cool air from the cool air circulation space between the inner box bottom wall and the outer box to the cooling space, and one end of the duct is in contact with the inner box side wall. A low-temperature storage, wherein the contact and the other end extend into the cooling space.