JP3171010B2 - Refrigeration system for binary refrigeration system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system for a binary refrigeration system comprising an outdoor unit serving as a heat source and a cooling unit provided with a cascade condenser.

[0002]

2. Description of the Related Art Conventionally, a refrigerating apparatus of a binary refrigerating system using a cascade condenser is disclosed in, for example, Japanese Patent Laid-Open No. 5-5 / 1993.
It is known as shown in Japanese Patent Application No. 567.

As shown in FIG. 5, the refrigerating apparatus disclosed in this publication is such that an outdoor unit A serving as a heat source and a cooling unit U having a cascade condenser C are separated from each other. A includes a primary compressor D and a primary condenser E, and a cooling unit U includes a secondary compressor F
And the cascade condenser C as well as an evaporator G. These devices are housed in a single casing H for factory assembly, and locally, the cooling unit U is provided. Is disposed on the top wall portion t of the freezer R provided in the building, the secondary compressor F and the cascade condenser C are mounted so as to be located outside the freezer, and the cascade is provided. The primary-side flow path a of the condenser C is connected to the primary-side condenser E and the primary-side compressor D of the outdoor unit A to be installed outdoors by connecting pipes M and N.

In FIG. 5, K is a backup auxiliary fan attached to the cascade capacitor C,
P is an expansion valve interposed between the cascade condenser C and the evaporator G, and Q is an evaporator fan attached to the evaporator G.

[0005]

According to the cooling device configured as described above, since the cooling unit U is factory-assembled, the on-site installation is performed by the top wall t of the freezer R. placed, the communication pipe M, attached only by connecting the N, but as it can simplify the site construction, the cooling unit U, the 2
Since the secondary compressor F, the cascade condenser C and the evaporator G are integrally incorporated, the weight becomes large, and much labor or mechanical force is required to lift and install the top wall t. There was a problem.

In particular, the capacity of the freezer R becomes large,
In order to increase the cooling capacity, the cooling unit U is also large, and the weight is heavy, so that the installation workability is further deteriorated. There is a problem that the space in the house cannot be used effectively, and there is also a problem in performing the maintenance of the cooling unit U.

The cooling unit U is provided on the top wall t.
It is necessary to form a large through hole in the top wall portion t and mount it in a penetrating manner, and therefore, it is necessary to seal a gap between the through hole and the casing H. In addition, the seal length of the gap becomes the outer peripheral length of the casing H, and the length thereof becomes longer. Thus, there is a problem that a problem occurs in the sealability depending on the seal structure.

It is an object of the present invention to reduce the weight even if the cooling capacity is increased, to improve the installation, and to reduce the space above the top wall of the freezer, thereby reducing the space in the freezer. It is an object of the present invention to provide a cooling device which can be used effectively, furthermore, the maintenance property can be improved, and the sealing property can be advantageously improved.

[0009]

According to the first aspect of the present invention,
An outdoor unit 3 having a primary side compressor 1 and a primary side condenser 2,
Secondary compressor 4, cascade condenser 5, and evaporator 6
And a cooling unit having a primary side flow path 5a of the cascade condenser 5 connected to the primary side condenser 2 and the primary side compressor 1 of the outdoor unit 3 by communication pipes 7, 8. In the cooling device of the refrigeration system, the cooling unit is divided into one external unit 9 having the secondary compressor 4 and the cascade condenser 5 and plural internal units 10 having the evaporator 6. Separate the 2 of the cascade capacitors 5
The liquid side of the secondary flow path 5b is connected to a plurality of liquid side connecting pipes 1 having a heat insulating structure.
Through one connected to the evaporators 6 of the plurality storage room machine 10, via a plurality of gas side communication pipe 12 to the outlet side of each evaporator 6 to the suction side of the secondary compressor 4 are connected Te,
The outside machine 9 is installed on the outside floor side of the freezer 13
This is a cooling device for a binary refrigeration system .

[0010] Also, a second aspect of the present invention, by placing the outside-compartment motor 9 in compartment outside the floor side of the freezer 13 is provided with the internal unit 10 in the internal upper part of the freezer 13, the outside-compartment motor 9 Gas side connecting pipe 1 for connecting the secondary compressor 4 of the above and the evaporator 6 of the internal unit 10
2 was piped in the refrigerator.

Further, the invention according to claim 3 is characterized in that the secondary expansion mechanism 14 is provided at the entrance side of the evaporator 6 in the internal machine 10.
Interposed, and the inlet side of the expansion mechanism 14, and than connecting the liquid side of the secondary flow path 5b of the cascade condenser 5 via a high-pressure liquid side communication pipe 11a, further, the invention of claim 4, wherein Is that the internal machine 10 is installed outside the freezer 13, and the outlet 10 a of the internal machine 10 is opened inside the freezer 13.

Further, in the invention according to claim 5 , the outdoor unit 9 is incorporated in the outdoor unit 3 to form the heat source unit 22.

[0013]

[0014]

According to the first aspect of the present invention, the cooling unit includes an external unit 9 having a primary compressor 1 and a cascade condenser 5, and an internal unit 10 having an evaporator 6.
Even if the cooling capacity is increased in accordance with the large capacity of the freezer, the external unit 9 and the internal unit 10 can be reduced in size and weight, and when installed in the freezer, The installation workability can be improved, the installation cost can be reduced, and the maintenance can be facilitated.

In addition, since the external machine 9 can be installed on the floor outside the warehouse,
The installation work can be further improved, and the space above the freezer can be reduced.

In addition, there is no need to form a large through hole in the freezer as in the conventional example, and it is sufficient to simply penetrate the connecting pipes 7 and 8, so that the seal of the freezer is not required.
Can be improved.

Further, a plurality of internal machines 10 are used,
The temperature distribution inside the refrigerator
And the installability of the internal machine 10 can be improved.
is there. Further, since the installed pre Symbol outside-compartment motor 9 on the floor side of the outside-compartment, further can improve the installation work and maintenance is also able improved.

According to the second aspect of the present invention, after the external unit 9 is installed on the floor outside the external unit, the internal unit 10 is installed in the freezer, and the secondary compressor 4 and the internal unit Since the gas side communication pipe 12 connecting the evaporator 6 to the evaporator 6 is provided in the storage, the low-temperature (for example, −15 ° C.-40 ° C.) gas refrigerant evaporated in the evaporator 6 returns to the compressor 4. The heat insulation structure of the gas side communication pipe 12 can be simplified, the heat loss can be reduced as compared with the case of piping outside the refrigerator, and the problem of liquid return to the compressor 4 can be prevented.

According to the third aspect of the present invention, since the expansion mechanism 14 is interposed at the inlet side of the evaporator 6 in the internal machine 10, the liquid side communication connecting the cascade condenser 5 and the evaporator 6 is performed. Even if the pipe 11 is piped outside the warehouse,
Since the high pressure liquid pipe can be used as the external pipe section, the heat insulation structure can be simplified.

According to the fourth aspect of the present invention, the air conditioner is installed outside the in-compartment unit 10 and the outlet 10 of the in-compartment unit 10 is installed.
Since a is opened inside the freezer, it is necessary to seal around the outlet 10a as compared with the case where the internal unit 10 is provided inside the freezer, and the internal unit 10 has a heat insulating structure. Although it is necessary, there is an advantage that the installation work can be made easier and the maintenance can be made easier than in the case of the interior.

In the above configuration, it is necessary to provide a through hole for opening the air outlet 10a in the freezer. However, this through hole can be made smaller than the conventional example shown in FIG. Therefore, the sealing property can be improved.

Further, in the fifth aspect of the present invention, since the heat source unit 22 is formed by incorporating the outdoor unit 9 into the outdoor unit 3, the heat source unit 22 becomes large.
Since it can be installed on the outdoor floor side, the installation work does not become complicated, and the in-compartment unit 10 can be reduced in weight and size. Even when the cooling unit is suspended above, the installation can be easily performed, and the problem of the conventional example in which the cooling unit is integrally structured can be solved.

[0023]

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of the cooling device of the present invention is as follows: an outdoor unit 3 having a primary side compressor 1 and a primary side condenser 2 on the high temperature side;
Low temperature side secondary compressor 4 and cascade condenser 5
And a cooling unit having an evaporator 6 and connecting the primary side flow path 5a of the cascade condenser 5 to the primary side condenser 2 and the primary side compressor 1 of the outdoor unit 3 by connecting pipes 7, 8. The cooling unit is divided into an external unit 9 having the secondary compressor 4 and a cascade condenser 5 and an internal unit 10 having the evaporator 3 based on the binary refrigeration system described above. The liquid side of the secondary side flow path 5b of the condenser 5 is connected to the evaporator 6 of the in-compartment unit 10 via the liquid side communication pipe 11, and the outlet side of the evaporator 6 is connected to the secondary side compressor 4 Is connected via a gas-side communication pipe 12 to the suction side of the air conditioner.

In the first embodiment shown in FIG. 1, the outside machine 9 is installed on the outside floor side of a freezer 13 installed in a building, and the inside machine 10 is attached to the freezer 13. The secondary compressor 4 of the external unit 9 and the internal unit 1
A gas-side communication pipe 12 for connecting the evaporator 6 to the evaporator 6 is connected to the inside of the refrigerator.
The secondary side expansion mechanism 14 was interposed, and the inlet side of the expansion mechanism 14 was connected to the liquid side of the secondary side channel 5b of the cascade condenser 5 via the high-pressure liquid side communication pipe 11a.
In FIG. 1, 15 is a fan attached to the evaporator 6, 16 is a fan attached to the primary condenser 2, 17
Is a primary side expansion mechanism, and 18 is a backup fan.

In the above configuration, the primary compressor 1
And the primary condenser 2, the primary expansion mechanism 17 and the primary passage 5 a of the cascade condenser 5, a primary refrigeration cycle is formed. Secondary side flow path 5b, secondary side expansion mechanism 14
And the evaporator 6 forms a secondary refrigeration cycle. The heat exchange in the cascade condenser 5 causes waste heat in the secondary refrigeration cycle to be taken by the primary refrigeration cycle, and the outdoor unit 3 Is radiated outside from the primary side condenser 2 to the outside, and the condensing temperature of the secondary side flow path in the cascade condenser 5 is reduced due to waste heat removal in the secondary side refrigeration cycle. The temperature can be lower than the evaporation temperature in the primary flow path 5a in the cascade condenser 5, and the interior of the freezer 13 can be cooled to a desired low temperature by the dual refrigerating system shown in FIG.

In FIG. 2, the condensing temperature of the primary refrigeration cycle is 50 ° C.
The evaporation temperature in the primary flow path 5a, which evaporates by heat exchange with the secondary refrigeration cycle, is 5 ° C. Also, the condensation temperature in the secondary flow path 5b, which is condensed by heat exchange with the primary refrigeration cycle in the cascade condenser 5, becomes 15 ° C., and the evaporation temperature in the evaporator 6 can be set to −40 ° C.

In the first embodiment shown in FIG. 1, the cooling unit is separated into the outside unit 9 and the inside unit 10, and the outside unit 9 is installed on the floor outside the unit. because was suspended the internal mechanism 10 to-compartment top, the capacity of the freezer 13 is increased, even if increasing the cooling capacity, the dispersion of the cooling unit, compact the outside-compartment motor 9 and the internal machine 10 Since the weight can be reduced, the installation work can be easily performed even when the in-compartment unit 10 is mounted on the upper part of the interior, and the out-of-compartment unit 9 is installed on the outer floor side. The installation work can be easily performed as compared with the case where the work is mounted on the top wall of the freezer 13, so that the installation workability on site can be improved as a whole, and the installation cost can be reduced.

The freezer 13 is generally installed in a building, has a prefabricated structure, has a height near the ceiling of the building, and provides a sufficient cooling space by effectively utilizing the building space. It is hoped that it will be.

In the first embodiment, since the outside machine 9 is installed on the outside floor side and the inside machine 10 is mounted inside the refrigerator, the space above the top wall of the freezer 13 can be minimized.
Therefore, the cooling space in the refrigerator can be made sufficiently large with respect to the ceiling height of the building to meet the demand, and since the external machine 9 is installed on the floor outside the refrigerator, maintenance is also easy. Can be improved.

Further, in the first embodiment, since the gas side communication pipe 12 is provided in the storage, the gas side communication pipe 12
The heat insulation structure can be simplified, the heat loss can be reduced as compared with the case of piping outside the refrigerator, and the liquid can be prevented from returning to the secondary compressor 4. In addition, the freezer 13
It is only necessary to penetrate the gas-side communication pipe 12 and the liquid-side communication pipe 11 in the wall, so that it is not necessary to provide a large through hole as in the conventional example, and the sealing performance of the freezer 13 can be improved accordingly. .

Further, a secondary-side expansion mechanism 14 is provided at the inlet side of the evaporator 6 in the internal machine 10, and the expansion mechanism 1
Since the high-pressure liquid-side communication pipe 11a is connected to the inlet side of the pump 4, the liquid refrigerant flowing through the high-pressure liquid-side communication pipe 11a has a high temperature (15 ° C. in the example of FIG. 2), 9
In the case where the expansion mechanism 14 is provided, that is, the heat insulation structure can be simplified as compared with the case where connection is made by low-pressure liquid communication. The heat insulation structure can be advantageous.

In the above configuration, the liquid side communication pipe 11 may be provided in a refrigerator. However, the liquid refrigerant at 15 ° C. flows to the high pressure liquid side as described above. External piping is preferred. In any case, the liquid side communication pipe 11
Need to have a heat insulating structure.

The gas-side connecting pipe 12 is preferably a pipe in a refrigerator, but may be a pipe outside the refrigerator. In this case, in the example shown in FIG.
Since the gas refrigerant at 0 ° C. flows, it is needless to say that a heat insulating structure is required.

Next, a second embodiment shown in FIG. 3 will be described.
In the second embodiment, the internal machine 10 is installed on the top wall 13a of the freezer 13, and the outlet 10a of the internal machine 10 is opened inside the freezer 13. In this case, the internal machine 10 is housed in a casing 19 having a heat insulating structure, and a through-hole 13 corresponding to the air outlet 10 a of the casing 19 is provided in a top wall portion 13 a of the freezer 13.
b is provided to cool the cold air passing through the evaporator 6 to cool the inside of the freezer 13.

Further, the air inside the freezer 13 is taken in and supplied to the inlet side of the evaporator 6, and is supplied to the inlet side of the evaporator 6 in the casing 19 and the inside of the freezer 13. Forms an intake passage 10b for the air to be cooled, and in order to prevent the outgoing air from being short-circuited and taken into the intake passage 10b, the outgoing air from the outlet 10a is provided in the inside of the refrigerator. A guide plate 21 for guiding is provided.

In the second embodiment, it is necessary to seal the periphery of the outlet 10a, and a casing 19 having a heat insulating structure is required. Thus, there is an advantage that the installation operation of the in-compartment unit 10 can be further simplified and maintenance can be facilitated. Further, in the second embodiment, the gas-side connecting pipe 12 for connecting the outlet of the evaporator 6 and the suction side of the secondary compressor 4 of the external unit 9 is provided with an internal pipe as in the first embodiment. It may be. Also in the second embodiment, the secondary expansion mechanism 1
4 is preferably provided in the casing 19.

In any case, according to the second embodiment, as in the first embodiment, the on-site installation can be improved and the installation cost can be reduced. The sealing performance can be improved, the space above the top wall of the freezer 13 can be reduced, and the cooling space can be increased.

That is, in the second embodiment, it is necessary to provide a through hole for opening the outlet 10a and a through hole for the intake passage 10b in the top wall 13a of the freezer 13. Since the through-holes do not allow the cooling unit to penetrate as in the conventional example shown in FIG.
Since the size can be reduced and the duct configuration can be used, the sealing performance can be improved. In addition, since the external unit 9 separates the internal unit 10, even if the cooling capacity is increased,
The space above the top wall can be reduced.
In the second embodiment, the secondary compressor 4 provided in the outside machine 9 may be taken out of the outside machine 9 and attached to the outside of the casing of the inside machine 10.

In this case, the weight of the in-compartment unit 10 is added by the weight of the compressor 4. The connection structure by the pipe 12 is advantageous.

Next, a third embodiment shown in FIG. 4 will be described.
In the third embodiment, the outdoor unit 9 is incorporated in the outdoor unit 3 to form a heat source unit 22. in this case,
The in-compartment unit 10 may be provided in the freezer 13 as in the first embodiment, or may be provided in the top wall 13a as in the second embodiment.
It may be attached to.

In any case, since the outdoor unit 9 is incorporated in the outdoor unit 3, the heat source unit 22 is larger than the outdoor unit alone, but can be installed on the outdoor floor side. Is not complicated.

Further, since the in-compartment unit 10 is separated from the out-of-compartment unit 9, it can be reduced in weight and size. Therefore, even when the unit is hung above the interior as shown in FIG. Part 13a
Even when the cooling unit is mounted on the cooling unit, it can be easily installed, and the problem of the conventional example in which the cooling unit is integrally structured can be solved.

Further, in each embodiment described above, one internal machine 10 is provided for one freezer 13, but it is preferable to provide a plurality of internal machines. That is, although it depends on the height of the freezer 13, when the internal temperature is cooled to, for example, −30 ° C., a cooling capacity of 1 horsepower per 0.5 tsubo is generally required. For 13, a capacity of 40 horsepower is required. As described above, when the capacity of the freezer 13 is large, it is advantageous to arrange the refrigerators in a distributed manner using a plurality of internal machines 10 in that the temperature distribution in the refrigerator can be averaged, and the installation property is also improved. You can. Therefore, when a cooling capacity of 40 hp is required as described above, for example, the internal machine 10 having a capacity of 5 hp is required.
Are mounted in a distributed manner.

As described above, when a plurality of the internal units 10 are provided, even one external unit 9 can be used. Machine 10
Are connected via a plurality of gas side branch pipes and liquid side branch pipes.

The outside machine 9 is preferably installed on the outside floor side, but it may be supported on the outside wall surface or on a stand provided on the outside floor surface. .

[0047]

According to the first aspect of the present invention, the cooling unit includes the external unit 9 having the primary compressor 1 and the cascade condenser 5, and the internal unit having the evaporator 6. And the internal unit 10 even when the cooling capacity is increased due to the large capacity of the freezer.
Can be reduced in size and weight, so that when it is installed in a freezer, its installation workability can be improved, installation costs can be reduced, and maintenance can be facilitated.

In addition, since the external machine 9 can be installed on the floor outside the warehouse,
The installation work can be further improved, and the space above the freezer can be reduced.

Further, it is not necessary to form a large through-hole in the freezer as in the conventional example, and it is sufficient to simply penetrate the connecting pipes 7 and 8, so that the seal of the freezer is not required.
Can be improved.

Further, a plurality of internal machines 10 are used,
The temperature distribution in the refrigerator by arranging
And the installability of the internal machine 10 can be improved.
You. Also, because I installed the previous Symbol outside-compartment motor 9 on the floor side of the outside-compartment,
The installation work can be further improved, and the maintenance can be further improved.

According to the second aspect of the present invention, after the outside machine 9 is installed on the floor outside the house, the inside machine 10 is installed inside the freezer, and the secondary side compressor 4 and the inside machine Since the gas side communication pipe 12 connecting the evaporator 6 to the evaporator 6 is provided in the storage, the low-temperature (for example, −15 ° C.-40 ° C.) gas refrigerant evaporated in the evaporator 6 returns to the compressor 4. The heat insulation structure of the gas side communication pipe 12 can be simplified, the heat loss can be reduced as compared with the case of piping outside the refrigerator, and the problem of liquid return to the compressor 4 can be prevented.

According to the third aspect of the present invention, since the expansion mechanism 14 is interposed at the inlet side of the evaporator 6 in the internal machine 10, the liquid side communication connecting the cascade condenser 5 and the evaporator 6 is performed. Even if the pipe 11 is piped outside the warehouse,
Since the high pressure liquid pipe can be used as the external pipe section, the heat insulation structure can be simplified.

According to the fourth aspect of the present invention, the air conditioner is installed outside the indoor unit 10 and the outlet 10
Since a is opened inside the freezer, it is necessary to seal around the outlet 10a as compared with the case where the internal unit 10 is provided inside the freezer, and the internal unit 10 has a heat insulating structure. Although it is necessary, there is an advantage that the installation work can be made easier than the interior and the maintenance can be made easier.

In the above configuration, it is necessary to provide a through hole for opening the outlet 10a in the freezer, but this through hole can be made smaller than the conventional example shown in FIG. Therefore, the sealing property can be improved.

Further, in the fifth aspect of the present invention, since the heat source unit 22 is formed by incorporating the outdoor unit 9 into the outdoor unit 3, the heat source unit 22 becomes large.
Since it can be installed on the outdoor floor side, the installation work does not become complicated, and since the in-compartment unit 10 can be reduced in weight and size, even when it is attached to the top wall of the freezer, Even when the cooling unit is suspended above, the installation can be easily performed, and the problem of the conventional example in which the cooling unit is integrally structured can be solved.

[0056]

[Brief description of the drawings]

FIG. 1 is a piping system diagram showing a first embodiment of the present invention.

FIG. 2 is a refrigeration cycle diagram in the first embodiment.

FIG. 3 is a piping diagram showing a second embodiment of the present invention.

FIG. 4 is a piping diagram showing a third embodiment of the present invention.

FIG. 5 is a piping system diagram showing a conventional example.

[Explanation of symbols]

1 Primary compressor 2
Primary condenser 3 Outdoor unit 4
Secondary compressor 5 Cascade condenser 5a
Primary flow path 5b Secondary flow path 6
Evaporator 7,8 Connecting pipe 9
Outside machine 10 Inside machine 11
Liquid side connecting pipe 12 Gas side connecting pipe 13
Freezer 14 Secondary expansion mechanism 18
Air outlet 22 Heat source unit

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-263553 (JP, A) JP-A-4-165275 (JP, A) JP-A-5-18647 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F25B 7/00

Claims (5)

(57) [Claims] An outdoor unit (3) having a primary compressor (1) and a primary condenser (2), a secondary compressor (4), a cascade condenser (5) and an evaporator (1). 6), and the primary side flow path (5a) of the cascade condenser (5) is connected to the primary side condenser (2) and the primary side compressor (1) of the outdoor unit (3). ), The cooling unit is connected to the secondary-side compressor (4) in the cooling device of the binary refrigeration system connected by the communication pipes (7) and (8).
A cascade condenser (5) and one compartment outside machine with (9) and the evaporator (6) a plurality of the internal machine with (1
0) and 2 of the cascade capacitor (5).
The liquid side of the secondary flow path (5b) is connected to each of the vaporizers (6) of the plurality of internal machines (10) through a plurality of liquid side communication pipes (11) having a heat insulating structure. The outlet side of each evaporator (6) is connected to the suction side of the secondary-side compressor (4) via a plurality of gas-side communication pipes (12 ). Is frozen
A cooling device for a binary refrigeration system, wherein the cooling device is installed on the outside floor side of a refrigerator (13) . 2. An outside machine (9) is installed on the outside floor side of a freezer (13), and an inside machine (10) is provided on the inside of the freezer (13). The binary refrigeration system according to claim 1, wherein a gas-side connecting pipe (12) connecting the secondary compressor (4) of the above and the evaporator (6) of the in-compartment unit (10) is provided in the compartment. Cooling system . 3. A secondary expansion mechanism (14) is interposed at the inlet side of the evaporator (6) in the internal machine (10), and the inlet side of the expansion mechanism (14) is connected to the high-pressure liquid side communication pipe. (11a) through the secondary flow path (5b) of the cascade condenser (5)
The cooling device for a binary refrigeration system according to claim 1, wherein the cooling device is connected to a liquid side. 4. An internal machine (10) is installed outside the freezer (13), and an outlet (10) of the internal machine (10) is provided.
The cooling device for a binary refrigeration system according to claim 1, wherein a) is opened inside the freezer (13). 5. The cooling device for a binary refrigeration system according to claim 1, wherein the outdoor unit (9) is incorporated in the outdoor unit (3) to form a heat source unit (22).