JPH10148445A - Low temperature showcase - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low temperature showcase in which a storing chamber can be kept at such a low humidity as one suitable for keeping a chocolate or the like without damaging a cooling action. SOLUTION: A low temperature showcase 1 is constructed such that a cooling unit 16 included in a cooling device R is installed in a cooling chamber 8 separately defined from a storing chamber 6, cold air heat-exchanged with the cooling unit 16 is discharged into the storing chamber 6 from a discharging port 12 under an operation of a plurality of blowers 21, sucked into the cooling chamber 8 through an inlet 13, wherein a plurality of blowers 21 are mounted and two sets of blowers are arranged to form a pair. During an operation of a compressor 32, the respective blowers are rotated in a same direction, and during the interruption of operation of the compressor the blowers are of the pair are rotated in opposite directions from each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-temperature showcase for displaying products such as chocolate that need to be stored at low temperature and low humidity.

[0002]

2. Description of the Related Art Conventionally, a low-temperature showcase for this kind of fresh confectionery is disclosed, for example, in Japanese Patent Publication No. 7-33949 (F25D21).
As shown in / 14), a storage room surrounded by a transparent plate is formed at the upper part, and fresh confectionery is displayed in the storage room, and a cooling room partitioned from the storage room is formed in a lower heat insulating wall. Then, a cooler is installed in the cooling room, and the storage room is cooled to a predetermined temperature by forcibly circulating the cool air having exchanged heat with the cooler into the storage room by a blower.

[0003] In this case, the compressor which forms a cooling device together with the cooler is turned on (operating) -OF at a set temperature in the storage chamber.
F (stop), and the compressor is turned off during the defrosting of the cooler, but the blower is normally operated continuously. Therefore, when the compressor is ON, the moisture in the storage chamber adheres to the cooler, and the dehumidifying effect works. However, when the compressor is OFF, the moisture in the cooling chamber is conversely brought into the storage chamber and the storage chamber becomes high. It was in the form of humidity.

[0004]

However, when storing chocolate or the like, the temperature is + 18 ° C to 22 ° C.
℃ and humidity of 40% to 45% are optimal, and if the blower is continuously operated as in the past, the humidity in the storage room becomes too high, so-called blooming phenomenon in which fat is exposed on the chocolate surface occurs, and the commercial value There is a problem that the temperature decreases.

Therefore, conventionally, measures have been taken such as stopping the blower while the compressor is turned off. However, when the blower is stopped, frost formation on the cooler gradually increases. Eventually, a frost blockage state occurs, and the cooling effect is significantly reduced, causing a problem that the temperature of the storage room rises.

On the other hand, stopping the blower causes a temperature irregularity in the storage room, and at this point, there is a problem that the cooling effect is reduced.

The present invention has been made to solve the above-mentioned conventional technical problem, and can maintain a storage room at a low humidity suitable for storing chocolate or the like without impairing the cooling function. It is intended to provide a low-temperature showcase.

[0008]

According to a first aspect of the present invention, there is provided a low-temperature showcase in which a cooler included in a cooling device is installed in a cooling room partitioned from a storage room, and a plurality of cool air that has exchanged heat with the cooler is provided. The blower discharges the air from the discharge port into the storage chamber, and the air is sucked into the cooling chamber from the suction port.An even number of the blowers are installed, and two of them are paired with each other. During operation, the fans are rotated in the same direction, and when the cooling device is stopped, the fans forming a pair are rotated in opposite directions.

According to the first aspect of the present invention, an even number of blowers for circulating the cool air exchanged with the cooler provided in the cooling chamber into the storage chamber are provided, and two blowers are paired with each other. At the same time, each fan is rotated in the same direction during operation of the cooling device, and while the cooling device is stopped, the paired fans are rotated in opposite directions to each other. The heat-exchanged cool air is discharged into the storage chamber by the blower to exert cooling and dehumidifying effects, and can be circulated only in the cooling chamber without discharging the cool air into the storage chamber while the cooling device is stopped.

Accordingly, it is possible to prevent a rise in humidity in the storage room caused by discharging cold air that has exchanged heat with the cooler into the storage room while the cooling device is stopped, thereby preventing deterioration in quality of products such as chocolate. become able to.

In particular, since the air is constantly circulated by the blower in the cooler, the occurrence of frost blockage can be prevented or suppressed, and the cooling function can be maintained well. Things.

A low-temperature showcase according to a second aspect of the present invention is provided with a shutter that opens and closes the discharge port and the suction port, respectively. The shutter opens and discharges the discharge port and the suction port during operation of the cooling device. While the apparatus is stopped, the discharge port and the suction port are closed.

According to the second aspect of the present invention, in addition to the above, there are provided shutters for opening and closing the discharge port and the suction port, respectively. These shutters open the discharge port and the suction port during operation of the cooling device, and provide cooling. Discharge port and suction port are closed when the device is stopped, so that cooling air circulation to the storage room when the cooling device is stopped is reliably prevented while maintaining cooling air circulation to the storage room during operation of the cooling device. It is possible to do. Therefore, it is possible to more effectively prevent an increase in the humidity of the storage room, and to further improve the storage performance of products such as chocolate.

According to a third aspect of the present invention, there is provided a low-temperature showcase according to the above invention, wherein a defrost heater is provided in the cooling chamber and the blower blows the defrost heater toward the cooler while the cooling device is stopped. It is arranged between coolers.

According to the third aspect of the present invention, in addition to the above inventions, a defrost heater is provided in the cooling chamber, and the blower blows the defrost heater toward the cooler while the cooling device is stopped. Since it is arranged between the coolers, during the defrosting of the cooler performed by stopping the cooling device, the heat of the defrost heater can be effectively introduced to the cooler by the blower,
The defrosting of the cooler is completed quickly, so that a decrease in the cooling function in the storage room can be minimized.

In a low-temperature showcase according to a fourth aspect of the present invention, a cooler included in a cooling device is installed in a cooling room partitioned from a storage room, and cool air that has exchanged heat with the cooler is discharged by a first blower. And a suction duct formed in the cooling chamber, bypassing the cooler, and communicating between the suction port and the discharge port, and a bypass duct formed in the cooling chamber. And a second blower provided in the, the first blower is operated during operation of the cooling device, the second blower is stopped, and the first blower is stopped while the cooling device is stopped. Stop and operate the second blower.

According to the fourth aspect of the present invention, a bypass duct is formed in the cooling chamber to bypass the cooler and communicate the suction port and the discharge port, and a second blower is provided in the bypass duct. During the operation of the cooling device, the first fan was operated, the second fan was stopped, and during the stop of the cooling device, the first fan was stopped and the second fan was operated. During operation of the cooling device, the first air blower maintains the circulation of cool air to the storage room, while the cooling device is stopped, the second air blower bypasses the cooler and passes through the bypass duct while the cooling device is stopped. Can be circulated into the storage chamber.

[0018] Accordingly, it is possible to prevent a rise in humidity in the storage room caused by discharging cold air that has exchanged heat with the cooler into the storage room while the cooling device is stopped, thereby preventing quality deterioration of chocolate and other products. Will be able to In particular, since the dry air is constantly circulated in the storage room by the second blower, the occurrence of temperature unevenness in the storage room can be prevented, and the cooling operation can be favorably maintained.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of a low-temperature showcase 1 of the present invention, FIG. 2 is a vertical side view of the low-temperature showcase 1, FIGS. 3 and 4 are perspective perspective views of the low-temperature showcase 1 for explaining cooling air circulation, and FIG. FIG. 6 is a plan view of the inside of the cooling chamber 8, and FIG. 6 is an electric circuit diagram of the low-temperature showcase 1.

The low-temperature showcase 1 of the present invention is a closed type showcase for chocolates installed in a confectionery store or the like. The low-temperature showcase 1 is a container-like heat-insulating wall 2 opened upward, and is erected on the heat-insulating wall 2. , A transparent wall (made of glass) 2 constituting a front surface continuous from the upper surface, transparent walls 3 and 3 (made of glass) on both sides, and a sliding door type glass door 4 on the rear surface.

Then, the transparent walls 2, 3,.
3 and a glass door 4... And a storage room 6 surrounded by a deck pan 7 in the heat insulating wall 2.
A cooling chamber 8 is formed. The storage room 6
A shelf 9 (FIG. 2) or a plurality of stages (FIG. 1) for merchandise display is erected in the inside, and the tip of the shelf 9 and the storage room 6 are provided.
Fluorescent lamps 11 and 11 for lighting are attached to the ceiling of the camera.

A discharge port 12 and a suction port 13 are formed at the rear end and the front end of the deck pan 7, and the storage chamber 6 and the cooling chamber 8 communicate with each other. Furthermore,
Shutters 14, 14 are provided at each discharge port 12 and suction port 13.
Are attached. These shutters 1
4 and 14 are driven by a solenoid 14S described later,
The discharge port 12 and the suction port 13 are simultaneously opened and closed in conjunction with each other.

A plate fin type cooler 16 is installed in the cooling chamber 8 across the left and right. Further, a fan case 17 is mounted on the front side of the cooler 16. Inside are four blowers 18, 19, 20, 2 consisting of a propeller fan and a motor.
1 (first blowers) are arranged side by side at equal intervals on the left and right.
In this case, openings 22 are formed in the front surface 17A of the fan case 17 in correspondence with the fans 18 to 21.

Further, between the front face 17A and the cooler 16, between the blower 18 and the blower 19, between the blower 19 and the blower 20, and between the blower 20 and the blower 21, partition plates 23, 24 and 26 are attached. Further, a defrost heater 28 composed of an electric heater is attached between the cooler 16 and the blower 18 at the left end and the right end, and between the blower 21 and the cooler 16, respectively.

The blowers 18 to 21 rotate forward to blow air toward the cooler 16, and reversely rotate to draw air from the cooler 16. The blower 18 forms a pair with the blower 19, and the blower 20 forms a pair with the blower 21. Further, a machine room 31 is formed below the heat insulating wall 2, and a compressor 32 that forms a refrigeration cycle of the cooling device R together with the cooler 16 in the machine room 31.
A condenser 33 and a condenser blower 34 are provided.

Next, in the electric circuit shown in FIG. 6, a defrost timer 36 is connected to the commercial AC power supply AC, and a thermostat 37 is provided between the common contact of the defrost timer 36 and the power supply AC. The compressor 32, the condenser blower 34, and the coil 39 of the fan relay 38 are connected in parallel between the normally closed contact of the frost timer 36 and the power supply AC.

The blower 19 is connected to the power supply AC in series with the first switching contact 41 of the fan relay 38, and the blower 20 is connected to the power supply A in series with the second switching contact 42 of the fan relay 38.
It is connected to C. The solenoid 14S for driving the shutter 14 is connected to the normally open contact 4 of the fan relay 38.
3 in series with the power supply AC.

A capacitor C is connected between the normally open contact and the normally closed contact of each of the switching contacts 41 and 42 so that when each of the switching contacts 41 and 42 is closed to the normally open contact. The blowers 19 and 20 are configured to rotate forward, and to rotate reversely when closed to a normally closed contact.
The other blowers 18 and 21 are connected to a power supply AC, and are energized and always rotate forward.

The normally open contact of the defrost timer 36 and the power supply AC
The coil 47 of the defrosting relay 46 is connected between them,
The parallel circuit of the defrost heaters 28 and 29
Are connected to the power supply AC in series with the normally open contacts.

With the above configuration, the low-temperature showcase 1 is next.
Will be described. Assuming that it is not defrosting now,
The contact of the defrost timer 36 is closed to a normally closed contact. on the other hand,
The thermostat 37 senses the temperature in the storage compartment 6 and opens contacts at, for example, + 18 ° C. and closes contacts at + 22 ° C.

When the temperature in the storage chamber 6 is higher than + 22 ° C. and the thermostat 37 closes the contacts, the compressor 32 and the condenser blower 34 are energized and operated (ON), and the cooler 16 exhibits a cooling capacity. . Also, fan relay 38
The coil 39 is also energized, and the switching contacts 41 and 42 are closed to the normally open contacts, whereby all the blowers 18 to 21 rotate forward and blow the air in the cooling chamber 8 to the cooler 16. Further, the normally open contact 43 is closed, and the solenoid 1 is closed.
4S, the discharge port 1 is
2 and the suction port 13 are opened.

As a result, the cool air that has exchanged heat with the cooler 16 is accelerated by all the blowers 18 to 21 and discharged into the storage chamber 6 from the outlet 12 on the rear side. The cool air discharged into the storage chamber 6 is circulated and cooled in the storage chamber 6 as shown by arrows in FIGS. 2 and 3, and is then drawn into the cooling chamber 8 from the suction port 13 on the front side.

By the cooling, the temperature in the storage room 6 is increased by +1.
When the temperature drops to 8 ° C., the contacts of the thermostat 37 are opened, so that the compressor 32 and the condenser blower 34 are de-energized and stopped (OFF). Since the coil 39 of the fan relay 38 is also de-energized, each of the switching contacts 41 and 42 is closed to a normally-closed contact, whereby the blower 19 and the blower 20 are closed.
Rotates in the reverse direction to suck air from the cooler 16 side. Further, since the normally open contact 43 is also opened, the solenoid 14S
Is turned off, and the discharge port 12 and the suction port 13 are closed by the respective shutters 14 and 14.

As a result, as shown by arrows in FIGS. 4 and 5, the air (cool air) in the cooling chamber 8 around the cooler 16 is supplied to the left side of the cooler 16 where the blower 18 and the blower 19 are located, and to the blower 20. A loop is formed at the right side of the cooler 16 where the blower 21 exists, and the cooler 16 is circulated only in the cooling chamber 8, and is not circulated to the storage chamber 6.

By repeating the thermocycle, the storage room 6
Inside is maintained at about + 20 ° C. on average. Further, for example, when 12 hours have elapsed from the start of the operation, the defrost timer 36 closes to the normally open contact. Thus, the compressor 32 and the condenser blower 34 are de-energized and stopped (OFF) regardless of the thermostat 37. Since the coil 39 of the fan relay 38 is also de-energized, each switching contact 4
1, 42 close to normally closed contacts, whereby the blower 19
Then, the blower 20 rotates in the reverse direction and sucks air from the cooler 16 side.

Further, since the normally open contact 43 is also opened, the solenoid 14S is de-energized, and the discharge port 12 and the suction port 13 are closed by the shutters 14, 14, respectively. In addition, since the coil 47 of the defrost relay 46 is also energized, the defrost relay 46 closes to a normally open contact, whereby the defrost heater 2 is closed.
8, 29 start generating heat.

Thus, as described above, the air (cool air) in the cooling chamber 8 around the cooler 16 is supplied to the blower 18 and the blower 19.
A loop is formed by the left portion of the cooler 16 where the air exists, and the right portion of the cooler 16 where the blower 20 and the blower 21 are present, and the cooler 16 is circulated only in the cooling chamber 8. Is no longer circulated. In particular, the blower 18
The blower 22 blows air to the blower 16 via the defrost heater 29 or 28 to melt the frost on the cooler 16.

Incidentally, the defrosting is completed when the defrost timer 36 returns to the normally closed contact after a predetermined time.

As described above, according to the present invention, the blowers 18 to 21 are rotated forward while the compressor 32 is operating, and the blowers 19 and 20 are rotated reversely while the compressor 32 is stopped. During the operation of, the cool air exchanged with the cooler 16 is discharged into the storage room 6 by all the blowers 18 to 21,
In addition to exerting the cooling and dehumidifying effects, while the compressor 32 is stopped, the cool air is not discharged into the storage chamber 6 but can be circulated only in the cooling chamber 8.

Therefore, while the compressor 32 is stopped, the cooler 16
To prevent the rise in humidity in the storage room 6 caused by discharging the cold air having exchanged heat with the storage room 6 and maintain the humidity of 40% to 45% suitable for storing products such as chocolate, thereby deteriorating the quality. Can be prevented beforehand.

In particular, since air is constantly circulated in the cooler 16 by the blowers 18 to 21, the occurrence of frost blockage of the cooler 16 can be prevented.
The cooling action can be maintained well.

Further, there are provided shutters 14 and 14 for opening and closing the discharge port 12 and the suction port 13, respectively.
And the suction port 13 is opened, and the discharge port 12 and the suction port 13 are closed while the compressor 32 is stopped.
While maintaining the cool air circulation to the storage room 6 during the operation of the compressor 32, it is possible to reliably prevent the cool air circulation to the storage room 6 while the compressor 32 is stopped. Accordingly, it is possible to more effectively prevent a rise in the humidity of the storage room 6, and to further improve the storage performance of products such as chocolate.

Further, the defrost heaters 29 and 28 are connected to the blower 1
8 and 21 and the cooler 16, the blowers 18, 21 during the defrosting of the cooler 16 performed by stopping the compressor 32.
As a result, the heat of the defrost heaters 29 and 28 can be effectively introduced to the cooler 16, and the defrost of the cooler 16 is completed quickly (return time of the defrost timer 36 is shortened). In addition, it is possible to minimize a decrease in the cooling effect in the storage chamber 6 during the defrosting.

Next, another low-temperature showcase 1 of the present invention will be described with reference to FIGS. In each figure, the same reference numerals as those in FIGS. 1 to 6 denote the same elements, and a description thereof will be omitted. In this case, the discharge port 12 and the suction port 13 are not provided with a shutter, and the defrost heater is also omitted.

On the other hand, a bypass duct 52 is defined above the cooler 16 in the cooling chamber 8 between the deck pan 7 and the deck pan 7. It communicates with the outlet 12. A blower 5 is provided in front of the bypass duct 52.
A plurality (second blowers) 3 are arranged in parallel.

Further, the electric circuit in this case has a configuration as shown in FIG. 9, and the thermostat 37 is of a switching contact type. That is, the thermostat 37 senses the temperature in the storage room 6, closes to the a contact at + 22 ° C., and + 18 ° C.
To close the contact b. And compressor 32, blower 18-
21, the condenser blower 34 and the blower 53 are connected to the power supply AC through the thermostat 37, and the compressor 3
2. The blowers 18 to 21 (collectively shown) and the blower 34 for the condenser are connected to a contact, and the blower 53 is connected to a b contact.

Next, the operation of the low-temperature showcase 1 in this case will be described. When the temperature in the storage room 6 is higher than + 22 ° C. and the thermostat 37 closes the a contact, the compressor 3
2 and the condenser blower 34 are energized and operated (ON), and the cooler 16 exhibits a cooling capacity. In addition, blower 1
8 to 21 are also energized and rotate forward to blow the air in the cooling chamber 8 to the cooler 16.

As a result, the cool air that has exchanged heat with the cooler 16 is accelerated by the blowers 18 to 21 and the rear outlet 1
2 is discharged into the storage room 6. The cool air discharged into the storage room 6 is circulated and cooled in the storage room 6 as shown by a solid line arrow in FIG. 7 and then sucked into the cooling room 8 from the suction port 13 on the front side.

By the cooling, the temperature in the storage room 6 is increased by +1.
When the temperature drops to 8 ° C., the thermostat 37 closes to the contact b, so that the compressor 32, the condenser blower 34 and the blower 1
8 to 21 are de-energized and stopped (OFF).

On the other hand, since the blower 53 is energized and operated, cool air in the storage chamber 6 is sucked into the bypass duct 52 from the suction port 13, passes through the bypass duct 52, and flows from the discharge port 12 to the storage chamber 6. It will be ejected.

As a result, the cool air in the storage room 6 is circulated through the bypass duct 52 without passing through the cooler 16 as shown by the broken arrow in FIG. By repeating such a thermocycle, the inside of the storage room 6 is + 20 ° C on average.
Is maintained.

As described above, according to the low-temperature showcase 1 in this case, while the compressor 32 is operating, the coolers 32 to 21 maintain the cool air circulation to the storage room 6 by the blowers 18 to 21.
During the stop, the blower 53 allows the dry air passing through the bypass duct 52 to bypass the cooler 16 and circulate in the storage room 6.

This prevents a rise in humidity in the storage room 6 caused by discharging cold air, which has exchanged heat with the cooler 16 while the compressor 32 is stopped, into the storage room 6, thereby preserving products such as chocolate. By maintaining a suitable humidity of 40% to 45%, quality deterioration can be prevented beforehand. In particular, since dry air is constantly circulated in the storage room 6 by the blower 53, the occurrence of temperature unevenness in the storage room 6 can be prevented, and the cooling effect can be maintained well.

[0054]

As described above in detail, according to the first aspect of the present invention, an even number of blowers for circulating the cool air exchanged with the cooler installed in the cooling chamber into the storage room are installed, and two blowers are mutually connected. In addition to being configured to form a pair, while the cooling device is operating, each blower is rotated in the same direction, while the cooling device is stopped,
Since the pair of blowers are rotated in opposite directions to each other, during operation of the cooling device, the cool air that has exchanged heat with the cooler is discharged into the storage room by the blower to exert cooling and dehumidifying effects, and the cooling device During the stop, the cool air is not discharged into the storage chamber, but can be circulated only in the cooling chamber.

Therefore, it is possible to prevent a rise in humidity in the storage room caused by discharging cold air that has exchanged heat with the cooler into the storage room while the cooling device is stopped, thereby preventing deterioration of quality of products such as chocolate. become able to.

In particular, since the air is constantly circulated by the blower in the cooler, the occurrence of frost blockage can be prevented or suppressed, and the cooling function can be maintained well. Things.

According to the second aspect of the present invention, in addition to the above, there are provided shutters for opening and closing the discharge port and the suction port, respectively. Discharge port and suction port are closed when the device is stopped, so that cooling air circulation to the storage room when the cooling device is stopped is reliably prevented while maintaining cooling air circulation to the storage room during operation of the cooling device. It is possible to do. Therefore, it is possible to more effectively prevent an increase in the humidity of the storage room, and to further improve the storage performance of products such as chocolate.

According to the third aspect of the present invention, in addition to the above inventions, a defrost heater is provided in the cooling chamber, and the blower blows the defrost heater toward the cooler while the cooling device is stopped. Since it is arranged between the coolers, during the defrosting of the cooler performed by stopping the cooling device, the heat of the defrost heater can be effectively introduced to the cooler by the blower,
The defrosting of the cooler is completed quickly, so that a decrease in the cooling function in the storage room can be minimized.

According to the fourth aspect of the present invention, a bypass duct that bypasses the cooler and connects the suction port and the discharge port is formed in the cooling chamber, and a second blower is provided in the bypass duct. During the operation of the cooling device, the first fan was operated, the second fan was stopped, and during the stop of the cooling device, the first fan was stopped and the second fan was operated. During operation of the cooling device, the first air blower maintains the circulation of cool air to the storage room, while the cooling device is stopped, the second air blower bypasses the cooler and passes through the bypass duct while the cooling device is stopped. Can be circulated into the storage chamber.

Accordingly, it is possible to prevent a rise in humidity in the storage room caused by discharging cold air that has exchanged heat with the cooler into the storage room while the cooling device is stopped, thereby preventing deterioration of quality of products such as chocolate. Will be able to In particular, since the dry air is constantly circulated in the storage room by the second blower, the occurrence of temperature unevenness in the storage room can be prevented, and the cooling effect can be maintained satisfactorily.

[Brief description of the drawings]

FIG. 1 is a perspective view of a low-temperature showcase of the present invention.

FIG. 2 is a vertical side view of a low-temperature showcase of the present invention.

FIG. 3 is a perspective view of a low-temperature showcase for explaining cold air circulation during operation of the compressor.

FIG. 4 is a perspective view of a low-temperature showcase for explaining cold air circulation while the compressor is stopped.

FIG. 5 is a plan view of the inside of a cooling room of the low-temperature showcase of the present invention.

FIG. 6 is an electric circuit diagram of the low-temperature showcase of the present invention.

FIG. 7 is a vertical side view of another low temperature showcase of the present invention.

FIG. 8 is a perspective view of the low-temperature showcase of FIG. 7;

FIG. 9 is an electric circuit diagram of the low-temperature showcase of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low-temperature showcase 6 Storage room 8 Cooling room 12 Discharge port 13 Suction port 14 Shutter 16 Cooler 18-21 Blower (first blower) 28 Defrost heater 32 Compressor 52 Bypass duct 53 Blower (second blower) R Cooling system

Claims (4)

[Claims] 1. A cooling device included in a cooling device is installed in a cooling room partitioned from a storage room, and cool air that has exchanged heat with the cooling device is discharged into the storage room from a discharge port by a plurality of blowers. In the low-temperature showcase that is sucked into the cooling chamber from above, an even number of the blowers are installed, and the two blowers are paired with each other, and each of the blowers rotates in the same direction during the operation of the cooling device. A low-temperature showcase, wherein the paired blowers are rotated in mutually opposite directions while the cooling device is stopped. 2. A shutter for opening and closing a discharge port and a suction port, respectively. The shutter opens the discharge port and the suction port during operation of the cooling device, and the discharge port and the suction port during stop of the cooling device. The low temperature showcase according to claim 1, wherein the suction port is closed. 3. A defrost heater is provided in the cooling chamber, and the defrost heater is disposed between the blower that blows toward the cooler while the cooling device is stopped and the cooler. The low-temperature showcase according to claim 1 or 2. 4. A cooler included in the cooling device is installed in a cooling room separated from the storage room, and cool air that has exchanged heat with the cooler is discharged from the discharge port into the storage room by a first blower. A low-temperature showcase that is suctioned from the mouth into the cooling chamber; a bypass duct formed in the cooling chamber, which bypasses the cooler and communicates the suction port and the discharge port; and a bypass duct provided in the bypass duct. And a second blower,
While the cooling device is operating, the first blower is operated, the second blower is stopped, and while the cooling device is stopped, the first blower is stopped, and the second blower is operated. A low-temperature showcase characterized by: