JPH08303918A - Low temperature show case - Google Patents

Abstract

PURPOSE: To provide a low temperature show case which can realize the simplification of the piping in a shop and the reduction of the cost, and can suppress a gas leakage, energy loss, and the deterioration of an environment in the shop. CONSTITUTION: For a chilled case 3, cold air is circulated in a storage chamber 39 to cool it, and is equipped with a major evaporator 46 to which a refrigerant is fed by a separately installed conditioning unit being installed in a machine room, etc., and an auxiliary evaporator 47 to which a refrigerant is fed from a built-in type condensing unit 57 being provided in the chilled case 3.

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 installed in a store such as a supermarket or a convenience store.

[0002]

2. Description of the Related Art Conventionally, in a store such as a supermarket of this type, for example, Japanese Examined Patent Publication No. 7-1135 (F2).
5B47 / 02) or Japanese Patent Publication No. 7-6713 (F
25B47 / 02), a plurality of low temperature showcases (open showcases) are installed, and the evaporator of each low temperature showcase is a separate condensing unit separately placed in a machine room outside the store. The refrigerant was supplied from.

That is, a piping structure of a low temperature showcase installed in a conventional store such as a supermarket will be described with reference to FIGS. 7 and 8. In FIG. 7, 1
・ Is a refrigerating case for fruits and vegetables as a low-temperature showcase for storing and displaying fruits and vegetables. In addition, 2.
··· is an ice temperature case for fresh fish as a low-temperature showcase for storing and displaying fresh fish.
Is a chilled case for fresh fish as a low temperature showcase for storing and displaying fresh fish in a semi-frozen state (chilled food).

The cases 1, ..., 2 ... And 100 are installed along the wall surface of the store as shown in the figure, and the end side plates 4 are attached to the endmost refrigerating case 1 and the chilled case 100, respectively. . Further, corner side plates 6 are attached to adjacent corners of the refrigerating case 1 and the ice temperature case 2, and an intermediate side plate 7 is attached between the ice temperature case 2 and the chilled case 100 to partition them. .

An evaporator 8 is installed in a duct (not shown) of each refrigerating case 1 ... And an evaporator 9 is installed in a duct of each ice temperature case 2 ... An evaporator 101 is installed in the duct of the chilled case 100. On the other hand, 11 and 12 are separate refrigeration condensing units and ice temperature condensing units installed (separated) inside the machine room 13 constructed outside the store, and 102 is also inside the machine room 13. It is a separately installed condensing unit for chilled.

Each condensing unit is composed of a compressor and a condenser (not shown), and the inlet side of the evaporator 8 of the refrigerating case 1 ... Is refrigerated via the solenoid valve 14 and the expansion valve 16 respectively. Condensation unit 11
Are connected in parallel to the liquid refrigerant pipes 17 and the outlet sides of the evaporators 8 are connected in parallel to the gas refrigerant pipes 18 of the refrigeration condensing unit 11.

Further, the evaporator 9 of the ice temperature case 2 ...
The inlet side of each is connected in parallel to the liquid refrigerant pipe 22 of the ice temperature condensing unit 12 via the solenoid valve 19 and the expansion valve 21, and the outlet side of the evaporator 9 is connected to the ice temperature condensing unit 12 respectively. Are connected in parallel to the gas refrigerant pipe 23.

Further, the evaporator 101 of the chilled case 100
Is connected to the liquid refrigerant pipe 106 of the chilled condensing unit 102 via the expansion valve 104, and the outlet side of the evaporator 101 is connected to the gas refrigerant pipe 107 of the chilled condensing unit 102. .

With the above construction, when the compressor of the refrigeration condensing unit 11 is operated, the refrigerant is the liquid refrigerant pipe 17
After being decompressed by the expansion valve 16 respectively, they are supplied to the evaporator 8 of each refrigerating case 1 ... And evaporated there. The refrigerant enclosed in the refrigerant circuit at this time is, for example, R-22.
It is a refrigerant, and the evaporation temperature is set to −10 ° C., the evaporation pressure is set to 2.6 kg / square centimeter G, and the temperature inside the storage chamber of each refrigerating case 1 ... Is + 8 ° C.

The temperature of the storage chamber of each refrigerating case 1 ... Is controlled by a control device (hereinafter referred to as a control unit) (not shown) that detects the temperature of each storage chamber and controls the opening / closing of the solenoid valve 14, All solenoid valves 14 ...
When is closed, the compressor of the refrigeration condensing unit 11 is stopped.

When the compressor of the ice temperature condensing unit 12 is operated, the refrigerant is decompressed by the expansion valve 21 through the liquid refrigerant pipe 22, and then the ice temperature cases 2
.. is supplied to the evaporator 9 and evaporated there. The refrigerant enclosed in the refrigerant circuit at this time is also R-22 refrigerant, the evaporation temperature is, for example, -17 ° C, and the evaporation pressure is 1.8 k.
Each ice temperature case set to g / square centimeter G 2
The temperature in the storage room of ... is -3 ° C.

The temperature of the storage chamber of each of the ice temperature cases 2 ... Is controlled by a control unit (not shown) which detects the temperature of each storage chamber and controls the opening / closing of the solenoid valve 19.・ When is closed, the compressor of the ice temperature condensig unit 12 is stopped.

Further, the chilled condensing unit 10
When the second compressor is operated, the refrigerant is decompressed by the expansion valve 104 through the liquid refrigerant pipe 106, and then the chilled case 10
It is supplied to the evaporator 101 of 0, and evaporates there. The refrigerant sealed in the refrigerant circuit at this time is also the R-22 refrigerant, the evaporation temperature is, for example, -30 ° C, and the evaporation pressure is 0.6.
The temperature in the storage chamber of the chilled case 100 is set to −12 ° C. by setting kg / square centimeter G.

The temperature in the storage room of the chilled case 100 is controlled by a control unit (not shown) which detects the temperature and controls the opening / closing of the solenoid valve 104, and when the solenoid valve 104 is closed, the chilled condensate. The compressor of the unit 102 was also stopped.

[0015]

As described above, in the related art, since the refrigerant circuit is formed corresponding to each temperature zone of the low temperature showcase installed in the store, the number of merchandise items is relatively small. Even for the chilled case 100 that can be installed only on the stand (in the case of the above example), a condensing unit had to be installed in the machine room, and an independent refrigerant circuit had to be formed by the liquid refrigerant pipe 106 and the gas refrigerant pipe 107. .

Therefore, there is a problem that the cost increases and the risk of gas (refrigerant) leakage increases due to the large number of pipe connection points.

Therefore, for example, as shown in FIG. 8, the ice temperature condensing unit 12 is eliminated, and the chilled condensing unit 102 is provided with the ice temperature case 2 ... And the chilled case 1.
00, each evaporator 9 ..., 101 (in this case, the solenoid valve 1
Evaporator 101 is connected via 09, and the evaporation pressure adjusting valve 111 (set value 1.8 kg / square centimeter G) is provided only on the outlet side of the evaporator 9 ... of each ice temperature case 2 ... ), The evaporation temperature / pressure in each ice temperature case 2 ... And the chilled case 100, and the temperature in the storage chamber are the same as above.

According to this structure, although the above-mentioned complication of the refrigerant circuit is eliminated, this time the evaporation pressure adjusting valve 111 is removed.
Energy loss occurs in the condensing unit (in this case, the chilled condensing unit 10 needs to be estimated).
There is a problem that the cost is increased, such as the increase in capacity in 2).

On the other hand, if the chilled case 100 is a low temperature showcase with a built-in condensing unit, the above-mentioned chilled condensing unit and its associated refrigerant piping are not required, but the above-mentioned storage room temperature (- 1
2 ° C.), the compressor, condenser, etc. of the built-in condensing unit installed in the low-temperature showcase will increase in size, and it will be difficult to store it in the lower part of the chilled case 100. There has been a problem that waste heat and noise emitted from the sig unit into the store increase and cause environmental deterioration.

The present invention has been made in order to solve the above-mentioned conventional technical problems, and realizes simplification of piping in a store and cost reduction, gas leakage, energy loss, and deterioration of store environment. An object of the present invention is to provide a low-temperature showcase that can suppress the heat.

[0021]

The low-temperature showcase of the present invention circulates cold air in a storage chamber to cool it, and a refrigerant is supplied from a separate condensing unit installed in a machine room or the like. The main evaporator and the auxiliary evaporator to which the refrigerant is supplied from the built-in condensing unit provided in the low temperature showcase are provided.

In the low temperature showcase of the second aspect of the present invention, the evaporation temperature of the auxiliary evaporator is set lower than that of the main evaporator, and the temperature of the cold air discharged into the storage chamber or the temperature of the cold air discharged into the storage chamber is controlled by the controller. Based on this, the operation of the built-in condensing unit is controlled.

In the low temperature showcase of the third aspect of the present invention, the main evaporator is installed on the upstream side of the cool air from the auxiliary evaporator in the first aspect, and the temperature inside the storage chamber or the cool air discharged into the storage chamber is controlled by the control device. The refrigerant supply from the separate condensing unit to the main evaporator is controlled on the basis of the temperature.

[0024]

According to the low temperature showcase of the present invention, the main evaporator to which the refrigerant is supplied from the separate condensing unit installed in the machine room, and the built-in condensing unit provided in the low temperature showcase. Since the auxiliary evaporator to which the refrigerant is supplied is provided, the auxiliary evaporator cools the storage room of the low temperature showcase to a temperature range lower than that of the other low temperature showcases connected to the separate condensing unit. It becomes possible to do.

That is, since a low temperature showcase having a lower temperature range than the other can be formed in the refrigerant circuit of the separate condensing unit of one system, simplification of piping in the store and cost reduction are realized. Moreover, it becomes possible to suppress gas leakage from the pipe. In particular, since it does not use an evaporation pressure adjusting valve or the like, it is possible to reduce energy loss, and the cooling capacity from the main evaporator also reduces the load on the auxiliary evaporator.
It is possible to reduce the size of the built-in condensig unit, reduce waste heat and noise, and suppress the deterioration of the in-store environment.

Further, according to the low temperature showcase of the invention of claim 2, in addition to the above, the evaporation temperature of the auxiliary evaporator is set lower than that of the main evaporator, and the temperature is discharged into the storage chamber or the storage chamber by the control device. Since the operation of the built-in condensing unit is controlled based on the temperature of the cold air that is stored, it is possible to smoothly realize the temperature control inside the storage chamber when the evaporation temperature of the auxiliary evaporator is lower than that of the main evaporator. At the same time, it is possible to avoid the concentration of frost on the auxiliary evaporator, disperse the frost on the main evaporator, and suppress the decrease in cooling capacity due to frost blockage.

Further, according to the low temperature showcase of the invention of claim 3, in addition to claim 1, the main evaporator is installed upstream of the cool air from the auxiliary evaporator, and the temperature or storage in the storage chamber is controlled by the control device. Based on the temperature of the cool air discharged into the chamber, the refrigerant supply from the separate condensing unit to the main evaporator was controlled, so the evaporation temperatures of the auxiliary evaporator and the main evaporator are similar and When the main evaporator is easily frosted, the temperature inside the storage chamber can be smoothly controlled, and the concentration of frost on the main evaporator is avoided and the frost is dispersed on the auxiliary evaporator. This makes it possible to suppress a decrease in cooling capacity due to frost blockage.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a chilled case 3 as an embodiment of a low temperature showcase of the present invention, FIG. 2 is a vertical sectional side view of the chilled case 3, FIG. 3 is a diagram illustrating a piping configuration in a store according to the present invention, and FIG. FIG. 3 is a vertical sectional side view of the ice temperature case 2. still,
In each drawing, the same reference numerals as those in FIGS. 7 and 8 are the same.

The chilled case 3 of the embodiment, the refrigerating case 1 and the ice temperature case 2 described above are all vertical open showcases, and the heat insulating wall 32 having a substantially U-shaped cross section and the heat insulating wall 32 of the heat insulating wall 32 at the installation site. Side plates 33, 33 attached to both sides (in the case of being connected and installed as described later, instead of the side plates 33, 33, end side plates 4 described later)
And the intermediate side plate 7 is attached). An outer layer partition plate 34 and an inner layer partition plate 36 are attached to the inside of the heat insulating wall 32 with a space between each other, and the space between the heat insulating wall 32 and the outer layer partition plate 34 is between the outer layer duct 37 and the inner and outer layer partition plates 36, 34. Is the inner layer duct 38, and the inner side of the inner layer partition plate 36 is the storage chamber 39.

In the storage room 39, a plurality of shelves 41 ...
The deck pan 42 is attached to the bottom of the storage chamber 39, and the lower part of the deck pan 42 is a bottom duct 43 communicating with the ducts 37 and 38. A fan case 44 having a blower 45 built therein is installed in the bottom duct 43. Further, a main evaporator 46 is vertically installed in a lower portion of the inner layer duct 38 located behind the storage chamber 39, and the inner layer duct 3 above the main evaporator 46 is provided.
A sub-evaporator 47 is vertically installed in the unit 8.

An outer layer discharge port 52 and an inner layer discharge port 53 are arranged side by side at the upper edge of the front opening 51 of the storage chamber 39 surrounded by the heat insulating wall 32 and the side plates 33, 33. The outlet 52 communicates with the outer layer duct 37 and the inner layer discharge port 53 communicates with the inner layer duct 38. A suction port 54 is formed at the lower edge of the opening 51 and communicates with the bottom duct 43.

When the blower 45 in the fan case 44 is operated, the air in the bottom duct 43 is blown toward the rear inner and outer layer ducts 37 and 38, and is blown up as it is in the outer layer duct 37. In the inner layer duct 38, the main evaporator 46 and the auxiliary evaporator 47 are provided.
Is sequentially blown up and then blown out from the inner and outer layer discharge ports 52 and 53 at the upper edge of the opening 51 toward the suction port 54 at the lower edge.

As a result, an inner cool air curtain and an outer air curtain that protects the inner cool air curtain are formed in the opening 51 of the storage chamber 39, and the invasion of outside air from the opening 51 is prevented or suppressed. A part of the inner cool air curtain circulates in the storage chamber 39 to cool the storage chamber 39. The cold air and the like are sucked into the suction port 54.
To the bottom duct 43, and is sucked into the blower 45 again.

On the other hand, a built-in condensing unit 57 is installed below the heat insulating wall 32 between the base leg angle 56. The built-in condensing unit 57 includes a compressor 58, a condenser 59, a condenser blower 61, and the like, and constitutes the auxiliary evaporator 47 and a known refrigerant circuit.

An ice temperature case 2 (refrigerating case 1 which will be described later)
As shown in FIG. 4, the auxiliary evaporator 47 and the built-in condensing unit 57 are removed in the chilled case 3 shown in FIGS. 1 and 2, and the main evaporator 46 is replaced by the evaporator. Since it has a structure in which 9 is installed vertically, description thereof will be omitted.

Next, in FIG. 3, reference numerals 1 ... Represent a cold storage case for fruits and vegetables as a low temperature showcase for storing and displaying fruits and vegetables in the same manner as described above. Also, 2 ...
Is an ice temperature case for fresh fish as a low temperature showcase for storing and displaying the above-mentioned fresh fish, and four units are arranged in parallel. Then, one chilled case 3, which is the low temperature showcase of the present invention, is installed and used as a fresh fish for storing and displaying fresh fish in a semi-frozen state (chilled food).

Each case 1, ..., 2 and 3 is installed along the wall surface of the supermarket store as shown in FIG. 3, and the end side plates 4 are attached to the refrigerating case 1 and the chilled case 3 at the end, respectively. To be Further, corner side plates 6 are provided at adjacent corners of the refrigerating case 1 and the ice temperature case 2.
Is attached, and an intermediate side plate 7 is attached between the ice temperature case 2 and the chilled case 3 to partition them.

An evaporator 8 is installed in each of the inner layer ducts of the refrigerating cases 1 ... On the other hand, 11, 12
Is a separate condensing unit for refrigeration and a condensing unit for ice temperature, which are installed (separated) in the machine room 13 configured outside the store.

Each condensing unit is composed of a compressor and a condenser (not shown), and the inlet side of the evaporator 8 of the refrigerating case 1 ... Is for refrigerating via the solenoid valve 14 and the expansion valve 16, respectively. Condensation unit 11
Are connected in parallel to the liquid refrigerant pipes 17 and the outlet sides of the evaporators 8 are connected in parallel to the gas refrigerant pipes 18 of the refrigeration condensing unit 11.

Also, the evaporator 9 of the ice temperature case 2 ...
The inlet side of the main evaporator 46 of the chilled case 3 is connected to the ice temperature condensing unit 12 via the solenoid valve 19 (in this case, the solenoid valve is not connected to the main evaporator 46) and the expansion valves 21 and 64. Of the evaporator 9 and the main evaporator 46 are respectively connected in parallel to the liquid refrigerant pipe 22 of the gas refrigerant pipe 23 of the condensation unit 12 for ice temperature.
Are connected in parallel.

Next, FIG. 5 shows the refrigerant circuit of the chilled case 3,
A block configuration of an electric circuit of the control unit 71 as a control device is shown. The control unit 71 includes a temperature sensor 72 that detects the temperature of the cool air discharged from the inner layer discharge port 53 of the chilled case 3 or the temperature of the cool air in the storage chamber 39, and the storage that the temperature sensor 72 substantially detects. The operation of the compressor 58 of the built-in condensing unit 57 is controlled based on the temperature in the chamber 39.

When the compressor of the refrigeration condensing unit 11 is operated with the above configuration, the refrigerant is the liquid refrigerant pipe 17
After being decompressed by the expansion valve 16 respectively, they are supplied to the evaporator 8 of each refrigerating case 1 ... And evaporated there. The refrigerant enclosed in the refrigerant circuit at this time is, for example, R-22.
It is a refrigerant, and the evaporation temperature is set to −10 ° C., the evaporation pressure is set to 2.6 kg / square centimeter G, and the temperature inside the storage chamber of each refrigerating case 1 ... Is + 8 ° C.

The temperature of the storage chamber of each of the refrigerating cases 1 ... Is controlled by a control unit (not shown) that detects the temperature of each storage chamber and controls the opening / closing of the solenoid valve 14. When closed, the compressor of the refrigeration condensing unit 11 is stopped.

When the compressor of the ice temperature condensing unit 12 is operated, the refrigerant is decompressed by the expansion valve 21 through the liquid refrigerant pipe 22, and then the ice temperature cases 2 and
.. is supplied to the evaporator 9 and evaporated there. The refrigerant enclosed in the refrigerant circuit at this time is also R-22 refrigerant, the evaporation temperature is, for example, -17 ° C, and the evaporation pressure is 1.8 k.
It is set to g / square centimeter G. The cold air cooled by the evaporator 9 is discharged into the storage chamber 39 by the blower 45 as described above, whereby the ice temperature cases 2 ...
-The temperature in the storage chamber 39 is set to -3 ° C.

The temperature of each part in the ice temperature case 2 in this case is shown in FIG. That is, the temperature of the cold air passing through the evaporator 9 is -6 ° C.
Therefore, the temperature of the cool air discharged from the inner layer discharge port 53 is -6.
C., 0.degree. C. at the outer layer discharge port 52,
It becomes 3 ° C. Further, the cool air temperature of the air curtain of the inner layer sucked into the suction port 54 is 0 ° C., and that of the outer layer is + 1 ° C.
The temperature in the storage chamber 39 of each ice temperature case 2 is controlled by a control unit (not shown) that detects the temperature and controls the opening / closing of the solenoid valve 19.

On the other hand, the liquid refrigerant pipe 22 of the ice temperature condensing unit 12 is decompressed by the expansion valve 64, then supplied to the main evaporator 46 of the chilled case 3 and evaporated there. At this time, the evaporation temperature is −17 ° C. as described above, and the evaporation pressure is 1.8 kg / square centimeter G.

On the other hand, when the compressor 58 of the built-in condensing unit 57 is operated by the control unit 71, the refrigerant (similar R-22) is condensed in the condenser 58 and decompressed by the expansion valve (not shown). After that, it flows into the auxiliary evaporator 47 and evaporates. The evaporation temperature at this time is -3
The evaporation pressure is 0.3 kg / square centimeter G at 5 ° C.

When the blower 45 is operated as described above, the cool air discharged from the blower 45 into the inner layer duct 38 is first cooled by the main evaporator 46 to about -6 ° C. as shown in FIG. , Into the auxiliary evaporator 47. The cold air that has flowed into the auxiliary evaporator 47 is further cooled there, and its temperature drops to −20 ° C., and is discharged from the inner layer discharge port 53 (−2).
0 ° C).

When the temperature in the storage chamber 39 drops to, for example, -13 ° C. by the cold air supply, the control unit 71 stops the compressor 58. When the compressor 58 stops, the cooling temperature in the storage chamber 39 cannot be maintained only by the main evaporator 46, so the temperature in the storage chamber 39 rises (thus, the ice temperature condensing unit 12 is in continuous operation). . Then, when the temperature rises to −12 ° C., the control unit 71 restarts the compressor 58. As a result, the inside of the storage chamber 39 is maintained at -12 ° C on average.

In this case, the outer layer discharge port 52 of the chilled case 3 has a temperature of -5 ° C, and the cold air temperature of the inner and outer layer air curtains sucked into the suction port 54 becomes -4 ° C.

As described above, the chilled case 3 is installed in the machine room 13
Separately installed ice temperature condensig unit 12 installed in
Since the main evaporator 46 to which the refrigerant is supplied and the auxiliary evaporator 47 to which the refrigerant is supplied from the built-in type condensation unit 57 provided in the chilled case 3 are provided,
By the auxiliary evaporator 47, the inside of the storage chamber 39 can be cooled to a temperature zone lower than that of the other ice temperature cases 2.

That is, since the chilled case 3 of a lower temperature zone can be formed in the refrigerant circuit of the ice temperature condensing unit 12 of one system, simplification of piping in the store and cost reduction are realized. Moreover, it becomes possible to suppress gas leakage from the pipe. In particular, since no evaporation pressure adjusting valve is used, energy loss can be reduced, and the cooling capacity from the main evaporator 46 also reduces the load on the auxiliary evaporator 47. It is possible to reduce the size of the die condensing unit 57, reduce waste heat and noise, and suppress deterioration of the environment in the store.

Further, since the control unit 71 controls the operation of the compressor 58 of the built-in condensation unit 57 based on the temperature of the cool air detected by the temperature sensor 72, the temperature control in the storage chamber 39 can be smoothly realized. Like In particular, when the compressor 58 is stopped, frost is attached to the main evaporator 46 having a high evaporation temperature and the frosted parts are dispersed, so that the auxiliary evaporator 47 having a low evaporation temperature is frosted. Concentration can be avoided, and a decrease in cooling capacity due to frost blockage can be suppressed.

The above control method is effective when the evaporation temperature of the auxiliary evaporator 47 is significantly lower than the evaporation temperature of the main evaporator 46, but the evaporation temperatures of the auxiliary evaporator 47 and the main evaporator 46 are similar. If it is set to be frosted, frost is concentrated on the main evaporator 46 installed on the upstream side of the cool air.

In this case, therefore, an electromagnetic valve 63 is provided between the expansion valve 64 and the liquid refrigerant pipe 22 as shown by the broken line in FIG. 3, and based on the temperature detected by the temperature sensor 72 described above,
The control unit 71 controls opening / closing of the solenoid valve 63. As a result, while the electromagnetic valve 63 is closed, frost adheres to the auxiliary evaporator 47 on the downstream side and the frosted parts are dispersed, so that the main evaporator 46 on the upstream side is dispersed.
Concentration of frost on the frost can be avoided, and a decrease in cooling capacity due to frost blockage can be suppressed.

In this case, the compressor of the ice temperature condensing unit 12 is configured to stop when all the solenoid valves 19, ..., 63 are closed. Moreover, although the combination of the chilled case 3 and the ice temperature case 2 has been described in the embodiment, the present invention is not limited to this, and the present invention is also effective for other combinations, for example, the combination of the ice temperature case 2 and the refrigerating case 1. Needless to say.

[0057]

As described in detail above, according to the present invention, the main evaporator to which the refrigerant is supplied from the separate condensing unit installed in the machine room and the built-in condenser installed in the low temperature showcase. Since the auxiliary evaporator to which the refrigerant is supplied from the sig unit is provided, the temperature inside the storage chamber of the low temperature showcase by the auxiliary evaporator is lower than that of the other low temperature showcases connected to the separate condensing unit. It becomes possible to cool the belt.

That is, since a low temperature showcase having a lower temperature range than the other can be formed in the refrigerant circuit of the separate condensing unit of one system, simplification of piping in the store and cost reduction are realized. Moreover, it becomes possible to suppress gas leakage from the pipe. In particular, since it does not use an evaporation pressure adjusting valve or the like, it is possible to reduce energy loss, and the cooling capacity from the main evaporator also reduces the load on the auxiliary evaporator.
It is possible to reduce the size of the built-in condensig unit, reduce waste heat and noise, and suppress the deterioration of the in-store environment.

According to the invention of claim 2, in addition to the above, the evaporation temperature of the auxiliary evaporator is set lower than that of the main evaporator, and the temperature of the storage chamber or the cool air discharged into the storage chamber is controlled by the control device. Since the operation of the built-in condensing unit is controlled based on the temperature, when the evaporation temperature of the auxiliary evaporator is lower than that of the main evaporator, it becomes possible to smoothly realize temperature control in the storage chamber, It is possible to avoid the concentration of frost on the auxiliary evaporator, to disperse the frost on the main evaporator, and to suppress the decrease in cooling capacity due to frost blockage.

Further, according to the invention of claim 3, claim 1
In addition to installing the main evaporator on the upstream side of the cool air from the auxiliary evaporator, based on the temperature in the storage chamber or the temperature of the cool air discharged to the storage chamber by the control device, the separate condensing unit moves to the main evaporator. Since the refrigerant supply is controlled, the temperature control in the storage chamber can be controlled smoothly when the evaporation temperatures of the auxiliary evaporator and the main evaporator are close to each other and frost is likely to form on the upstream main evaporator. In addition, it is possible to avoid the concentration of frost on the main evaporator and disperse the frost on the auxiliary evaporator, and it is possible to suppress the decrease in cooling capacity due to frost blockage. It is a thing.

[Brief description of drawings]

FIG. 1 is a perspective view of a chilled case as an embodiment of a low temperature showcase of the present invention.

FIG. 2 is a vertical sectional side view of the chilled case of FIG.

FIG. 3 is a diagram illustrating a piping configuration in a store according to the present invention.

FIG. 4 is a vertical sectional side view of an ice temperature case.

FIG. 5 is a diagram showing a block configuration of a refrigerant circuit of a chilled case and an electric circuit of a control unit.

FIG. 6 is a diagram showing a block configuration of another refrigerant circuit of a chilled case and an electric circuit of a control unit.

FIG. 7 is a diagram illustrating a conventional piping configuration in a store.

FIG. 8 is a diagram illustrating another conventional piping configuration in a store.

[Explanation of symbols]

 2 Ice temperature case 3 Chilled case (low temperature showcase) 12 Ice temperature condensing unit 13 Machine room 45 Blower 46 Main evaporator 47 Auxiliary evaporator 57 Built-in condensing unit 58 Compressor 63 Solenoid valve 71 Control unit 72 Temperature sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Todoroki 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (3)

[Claims] 1. A low-temperature showcase in which cold air is circulated and cooled in a storage room, and a main evaporator to which a refrigerant is supplied from a separate condensing unit installed in a machine room and the low-temperature showcase are provided. A low-temperature showcase, which is equipped with an auxiliary evaporator to which a refrigerant is supplied from a built-in condensing unit. 2. The evaporation temperature of the auxiliary evaporator is set lower than that of the main evaporator, and the operation of the built-in condensig unit is controlled by the controller based on the temperature in the storage chamber or the temperature of the cool air discharged into the storage chamber. The low temperature showcase according to claim 1, wherein 3. The main evaporator is installed on the upstream side of the cool air with respect to the auxiliary evaporator, and based on the temperature in the storage chamber or the temperature of the cool air discharged into the storage chamber by the controller, the main unit is separated from the main condensing unit by the controller. The low temperature showcase according to claim 1, wherein the refrigerant supply to the evaporator is controlled.