KR20070087124A - Refrigerating apparatus - Google Patents

Abstract

A refrigerating apparatus, wherein, on the pressure loss of a refrigerant by a return side communication pipe (19) starting at the outlets (24), (34), and (44) of single stage side use units (12), (13), and (14) toward the inlet (61) of a heat source unit (11), the value of the pressure loss of the refrigerant by the return side communication pipe (19) connected to the single stage side use unit (14) with the lowest chamber set temperature among the plurality of single stage side use units (12), (13), and (14) is minimized.

Description

Freezers {REFRIGERATING APPARATUS}

The present invention relates to a refrigerating device in which a plurality of use units are connected in parallel to a heat source unit.

Background Art Conventionally, refrigeration apparatuses in which a plurality of use units are connected to each other in parallel to one heat source unit have been known. For example, they are installed in convenience stores and the like and used for refrigeration or freezing of display cases. In such a refrigerating device, a compressor and a heat source side heat exchanger are configured in the heat source unit, while a cooling heat exchanger and an expansion valve are respectively configured in the use unit, and the heat source unit and the use unit are connected by connecting pipes. In each use unit, the refrigerant evaporation temperature of the cooling heat exchanger is set in accordance with the set temperature in the storage, such as a showcase.

Patent Document 1 discloses a refrigeration apparatus of this kind. In Fig. 1 of Patent Document 1, a refrigeration apparatus is disclosed in which one indoor unit as a heat source unit is connected in parallel with three indoor units as a use unit. Three indoor units are composed of two refrigeration units and one refrigeration unit, and a booster unit having a compressor is connected in series to the refrigeration unit.

[Patent Document 1: Japanese Patent Application Laid-Open No. 2003-314909]

[Initiation of invention]

[Problem to Solve Invention]

However, when the above-mentioned refrigerating device is installed in a convenience store or the like, the arrangement of the heat source unit or the use unit is mainly determined by the layout and the use form of the facility where the refrigerating device is installed. According to the arrangement of the heat source unit or the use unit, the length of the connection pipe from the exit of each use unit to the heat source unit inlet is determined.

Accordingly, the length of the connection pipe from the outlet of each use unit to the inlet of the heat source unit may be longer for the use unit having a lower set temperature in the storage than the use unit having a high set temperature in the storage. In such a case, when the pressure loss of the refrigerant caused by the return connection pipe from the outlet of each use unit to the inlet of the heat source unit is also greater, the use unit having a lower set temperature in the store than the use unit having a high set temperature in the store becomes larger. There is.

At this time, the refrigerant pressure at each outlet of the use unit and the refrigerant evaporation pressure at each use unit are higher in the use unit having a lower set temperature in the storage than in the use unit having a high set temperature in the storage. For this reason, the refrigerant evaporation temperature in the use unit with a low set temperature in the storage becomes higher than the refrigerant evaporation temperature in the use unit with a high set temperature in the storage. That is, in the conventional refrigerating device, there is a case where the refrigerant evaporation temperature corresponding to the set temperature in the storage is not used in any of the use units.

This invention is made | formed in view of this point, Comprising: It aims at making the refrigerant evaporation temperature in a use unit suitable for the preset temperature in a storage, and aiming at the efficiency improvement of a refrigerating apparatus.

[Means for solving the problem]

Each of the first to fourth inventions has a single stage compression unit using units (12, 13) having cooling heat exchangers (21, 31, 41) for cooling the inside of the reservoir in order to maintain the inside of the reservoir at a predetermined set temperature. And a plurality of heat source units (11) having a compressor (29), and a plurality of said first stage compression-side use units (12, 13, 14) are provided with respect to said heat source unit (11). In the refrigerant circuit 20 connected in parallel with the connection pipes 18 and 19, the refrigerant is circulated between the one-stage compression-side use unit 12, 13 and 14 and the heat source unit 11, thereby providing one-stage compression refrigeration. It aims at the refrigeration apparatus 30 in which a cycle is performed.

And in the refrigerating device 30 of the first invention, the return from the outlet (24, 34, 44) of each of the single-stage compression-side use unit (12, 13, 14) to the inlet 61 of the heat source unit 11 The pressure loss of the refrigerant caused by the side connecting pipe 19 is a value due to the return side connecting pipe connected to the lowest set temperature in the reservoir among the plurality of single-stage compression side using units 12, 13, and 14. Minimum.

In the refrigerating device (30) of the second invention, the return side from the outlet (24, 34, 44) of each of the first stage compression-side use units (12, 13, 14) to the inlet (61) of the heat source unit (11). The pressure loss of the refrigerant by the connecting pipe 19 becomes smaller as the set temperature in the reservoir of the first stage compression-side use unit 12, 13, 14 to which the connecting pipe is connected is lower.

In the refrigerating device (30) of the third invention, the length of the connection pipe from the outlet (24, 34, 44) of each one-stage compression-side use unit (12, 13, 14) to the inlet (61) of the heat source unit (11) Is the shortest return side connecting pipe connected to the lowest set temperature in the storage, among the plurality of single-stage compression-side use units 12, 13, 14;

In the refrigerating device (30) of the fourth invention, the length of the connecting pipe from the outlet (24, 34, 44) of each of the first stage compression-side use units (12, 13, 14) to the inlet (61) of the heat source unit (11) The lower the set temperature in the reservoir of the first stage compression-side use unit 12, 13, 14 to which the connecting pipe is connected, the shorter it becomes.

In the fifth invention, in the invention of any one of the first to the fourth, the outlets 24, 34, 44 and the inlet of the heat source unit 11 of each of the first-stage compression-side use units 12, 13, 14, respectively. In the return-side connecting pipe 19 for connecting 61, the lowest set temperature in the storage is connected to the downstream of the plurality of single-stage compression-side use units 12, 13, 14.

In the sixth invention, in the fifth invention, an outlet 71 connecting the outlet 71 of the heat source unit 11 and the inlets 23, 33, 43 of each of the first-stage compression-side use units 12, 13, 14 is connected. In the side connecting pipe 18, the lowest set temperature in the reservoir is connected to the most upstream side among the plurality of single-stage compression-side use units 12, 13, and 14.

In the seventh aspect of the present invention, in any one of the first to sixth aspects, the two-stage compression-side use unit (15) having a cooling heat exchanger (51) for cooling the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. ) And a booster compressor 46 are connected in series to the two-stage compression side circuit 47, and in the refrigerant circuit 20, the two-stage compression side circuit 47 is connected to the one-stage compression side use unit 12. , 13 and 14 are connected in parallel to the heat source unit 11 in a connection pipe, and the refrigerant is circulated between the two-stage compression-side using unit 15 and the heat source unit 11 so as to provide two-stage compression refrigeration. The cycle is performed.

In the eighth invention, in the seventh invention, the outlets 24, 34, 44, 54 and the heat source unit of the respective first stage compression-side use units 12, 13, 14 and the second stage compression-side circuit 47, respectively. (11) In the return side connecting pipe 19 which connects the inlet 61, the two-stage compression side circuit 47 is connected to the most upstream side.

In the ninth invention, in the eighth invention, the heat source unit (11) outlet (71), the first stage compression side using unit (12, 13, 14) and the inlet (23) of the two stage compression circuit (47) In the sending side connecting pipe 18 for connecting, 33, 43 and 53, the two-stage compression side circuit 47 is connected to the most upstream side.

-Action-

In the first invention, the refrigerant pressure of the outlet 44 of the one-stage compression side using unit 14, which has the lowest set temperature in the reservoir, is the lowest among the plurality of single-stage compression-side using units 12, 13, and 14. . The refrigerant evaporation pressure at the one-stage compression side using unit 12, 13, 14 is approximately equal to the refrigerant pressure at the outlets 24, 34, 44 at the one-stage compression side using unit 12, 13, 14. That is, the evaporation pressure and the evaporation temperature of the refrigerant in the first stage compression unit using units 12, 13 and 14 are the refrigerants at the outlets 24, 34 and 44 of the first stage compression unit using units 12, 13 and 14. The lower the pressure, the lower. As a result, the refrigerant evaporation temperature of the first-stage compression-side use unit 14, which has the lowest set temperature in the reservoir, is the lowest among the plurality of first-stage compression-side use units 12, 13, 14.

In the second invention, the refrigerant pressures of the outlets 24, 34, 44 of each of the first-stage compression-side use units 12, 13, 14 are lowered in the order of the low set temperature in the reservoir. As a result, the evaporation pressure and the evaporation temperature of the refrigerant in the first-stage compression-side use units 12, 13, and 14 are also lowered in the order of decreasing setting temperature in the storage.

The pressure loss due to the connecting pipe is approximately proportional to the length of the connecting pipe. Therefore, in the third invention, the return side connecting pipe 19 from the outlets 24, 34, 44 of the first stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11 is provided. The pressure loss of the refrigerant caused by the refrigerant is likely to be minimized by the return-side connecting pipe connected to the lowest set temperature in the reservoir among the plurality of single-stage compression-side use units 12, 13, and 14.

In the fourth aspect of the present invention, the outlet side connecting pipes (19) from the outlets (24, 34, 44) of the first-stage compression-side use units (12, 13, 14) to the inlet (61) of the heat source unit (11). The pressure loss of the refrigerant caused by the refrigerant tends to be smaller as the set temperature in the storage of the first-stage compression-side use units 12, 13, 14 to which the connecting pipe is connected is lower.

In the fifth invention, the first-stage compression-side use unit 14 having the lowest set temperature in the reservoir is connected to the downstream side of the return side connecting pipe 19, i.e., close to the heat source unit 11.

In the sixth aspect of the present invention, the first-stage compression-side use unit 14 having the lowest set temperature in the reservoir connected to the downstream side of the return side connecting pipe 19, that is, the side close to the heat source unit 11, is connected to the delivery side. The pipe 18 is connected to the most upstream side, that is, the side closest to the heat source unit 11. In other words, the one-stage compression-side use unit 14 having the lowest set temperature in the reservoir where the refrigerant is easily connected to the heat source unit 11 in the return-side connecting pipe 19 is connected to the delivery-side connecting pipe 18. Is connected in a state where the refrigerant is easily introduced. Thus, the one-stage compression-side use unit 14 having the lowest set temperature in the reservoir, which requires a higher cooling capacity than the other one-stage compression-side use units 12 and 13, has the other one-stage compression-side use unit 12, Compared with 13), a large amount of liquid refrigerant is easily introduced.

In the seventh aspect of the present invention, among the refrigerant flowing out of the heat source unit (11), the refrigerant flowing into the one-stage compression-side use unit (12, 13, 14) is evaporated in each cooling heat exchanger (21, 31, 41). While returning to the heat source unit 11, the refrigerant flowing into the two-stage compression-side use unit 15 is evaporated in the cooling heat exchanger 51 and compressed in the booster compressor 46, and then returned to the heat source unit 11. . Therefore, the refrigerant from the two-stage compression-side using unit 15 is increased in the booster pressure measuring device 46 between the two-stage compression-side circuit 47 and the outlet 54, so that the two-stage compression-side using unit ( 15) it is possible to set the evaporation pressure and the evaporation temperature of the refrigerant to a lower value than the use unit (12, 13, 14) of the first stage compression.

In the eighth aspect of the present invention, the two-stage compression side circuit 47 to which the booster compressor 46 is connected is connected to the most upstream side in the return-side connecting pipe 19. The refrigerant pressure loss between the two-stage compression side circuit 47 and the heat source unit 11 is greater than the refrigerant pressure loss between the one-stage compression side use unit 12, 13, 14 and the heat source unit 11. Grows However, in the two-stage compression-side circuit 47, the refrigerant evaporated in the two-stage compression-side use unit 15 is compressed by the booster compressor 46 and then sent out. Thus, the evaporation temperature in the two-stage compression side using unit 15 is lower than that of the first-stage compression side using unit 12.

In the ninth aspect of the present invention, the two-stage compression side circuit 47 to which the two-stage compression side use unit 15 is connected is connected to the most upstream side where the refrigerant easily flows in the delivery-side connecting pipe 18. As a result, the liquid refrigerant easily flows into the two-stage compression-side use unit 15, which can set the evaporation pressure and the evaporation temperature of the refrigerant to a value lower than the one-stage compression-side use units 12, 13 and 14.

[Effects of the Invention]

According to the first invention, the refrigerant evaporation temperature in the first stage compressor side using unit 14, which has the lowest set temperature in the reservoir, is the lowest among the plurality of first stage compressor side using units 12, 13, 14. Is set. As a result, the refrigerant evaporation temperature of the first-stage compression-side use unit 14 to the cooling heat exchanger 41 having the lowest set temperature in the storage can be set to be the lowest so as to be appropriate to the set temperature in the storage. Cooling of the reservoir by the compression-side using unit 14 can be performed efficiently.

According to the second invention, the refrigerant evaporation temperature in each of the first-stage compression-side use units 12, 13, and 14 is set so that the set temperature in the reservoir is lowered in descending order. As a result, the set temperature in the reservoir is lowered so that the refrigerant evaporation temperature in the cooling heat exchangers 21, 31, and 41 of the first-stage compression-side use units 12, 13, and 14 is appropriate to the set temperature in the reservoir, respectively. It can be set in the order of low, and the storage of the storage by the single-stage compression-side use units 12, 13, 14 can be efficiently performed.

According to the third invention, by defining the length of the connection pipe from the outlet (24, 34, 44) of each one-stage compression side use unit (12, 13, 14) to the inlet (61) of the heat source unit 11, The pressure loss of the refrigerant caused by the return side connecting pipe 19 from the outlets 24, 34, 44 of the first-stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11, Among the plurality of single-stage compression-side use units 12, 13 and 14, the value by the return side connection pipe connected to the lowest set temperature in the reservoir tends to be minimum. As a result, it is advantageous to efficiently cool the reservoir by the first-stage compression-side use unit 14 having the lowest set temperature in the reservoir.

According to the fourth invention, by defining the length of the connection pipe from the outlets 24, 34, 44 of the first-stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11, The pressure loss of the refrigerant by the return side connecting pipe 19 from the outlets 24, 34, 44 of the first-stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11 is Further, the lower the set temperature in the reservoir in the first-stage compression-side use unit (12, 13, 14) to which the connection pipe is connected, the smaller the value becomes. As a result, it is advantageous to efficiently cool the reservoir by each of the single-stage compression-side use units 12, 13, and 14.

According to the sixth aspect of the present invention, the one-stage compression-side use unit 14 having the lowest set temperature in the storage, which requires higher cooling capacity than the other one-stage compression-side use units 12 and 13, has a return side connecting pipe ( In 19), the refrigerant is easily returned to the heat source unit 11, and in the connection side pipe 18, the liquid refrigerant from the heat source unit 11 is easily flowed in, and the other one-stage compression side use unit is connected. Compared with (12, 13), a large amount of liquid refrigerant is easily introduced. Therefore, the one-stage compression-side use unit 14 having the lowest set temperature in the reservoir can exhibit sufficient cooling capacity to maintain the inside of the reservoir at a predetermined set temperature.

In the seventh aspect of the invention, even if the evaporation pressure and the evaporation temperature of the refrigerant in the two-stage compression unit using unit 15 are set to a lower value than the one-stage compression unit using units 12, 13 and 14, the two-stage compression side circuit Before reaching the outlet 54 of 47, the refrigerant from the two-stage compression unit using unit 15 can be compressed by the booster compressor 46 to increase the refrigerant pressure. Accordingly, the two-stage compression-side use unit 15 is a one-stage compression-side use unit 12, 13, 14 without affecting the evaporation temperature and the evaporation pressure of the first-stage compression-side use unit 12, 13, 14. It can show high cooling capacity compared to).

According to the ninth aspect of the present invention, the two-stage compression-side use unit 15, which can set the evaporation pressure and the evaporation temperature of the refrigerant to a value lower than the one-stage compression-side use units 12, 13, 14, has a discharge side connection pipe ( In 18), the refrigerant is connected in a state where it is likely to flow. Therefore, since the two-stage compression side using unit 15 is easy to introduce a large amount of liquid refrigerant, even if the set temperature in the reservoir is set to a value lower than the one-stage compression side using unit (12, 13, 14), Sufficient cooling ability can be exhibited to maintain the predetermined set temperature.

1 is a schematic configuration diagram of a refrigerating device according to the first embodiment of the present invention.

2 is a schematic configuration diagram of a refrigerating device according to Modification Example 2 of the first embodiment of the present invention.

3 is a schematic configuration diagram of a refrigerating device according to a second embodiment of the present invention.

[Description of the code]

11: outdoor unit (heat source unit)

12: 1st refrigeration showcase (single-side compression unit)

13: second refrigerated display case (single-side compression unit)

14: 3rd refrigerated display case (unit using the first stage compression unit with the lowest set temperature in the storage)

15: freezing showcase (two-stage compression side use unit)

18: liquid side connection pipe (outgoing side connection pipe)

19: gas side connection pipe (return side connection pipe)

20: refrigerant circuit

21: Refrigerated heat exchanger (cold heat exchanger) of the first refrigerated showcase

23: inlet of the first refrigerated showcase (inlet of the first-stage compression side use unit)

24: Outlet of the first refrigerated showcase (outlet of the first-stage compression side use unit)

29 compressor 30 refrigeration unit

31: Refrigerated heat exchanger (cooling heat exchanger) of the second refrigerated showcase

33: entrance of the second refrigerated display case (inlet of the first-stage compression side use unit)

34: outlet of the second refrigerated display case (outlet of the first-stage compression side use unit)

41: Refrigerated heat exchanger (cooling heat exchanger) of the third refrigerated showcase

43: inlet of the third refrigerated display case (inlet of the first-stage compression side use unit)

44: Exit of the 3rd refrigerated display case (outlet of the first-stage compression side use unit)

46: booster compressor 47: two-stage compression circuit

51: refrigeration heat exchanger (cooling heat exchanger)

53: Inlet of two stage compression circuit 54: Outlet of two stage compression circuit

61: inlet of the outdoor unit (inlet of the heat source unit)

71: outlet of the outdoor unit (exit of the heat source unit)

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail based on drawing.

[First embodiment]

The refrigeration apparatus 30 of this embodiment is installed in a convenience store etc., and it cools in a showcase.

As shown in FIG. 1, the refrigerating device 30 of this embodiment is provided with the outdoor unit 11 which is a heat source unit, four showcases 12, 13, 14, and 15, and the booster unit 16. As shown in FIG. . The four showcases 12, 13, 14, and 15 are composed of a first refrigerated showcase 12 as a refrigerator, a second refrigerated showcase 13 and a third refrigerated showcase 14, and a frozen showcase 15 as a freezer. do. The outdoor unit 11 is installed outdoors. On the other hand, all four showcases 12, 13, 14, 15 are installed in stores, such as a convenience store.

The four showcases 12, 13, 14, and 15 are each set in a storage temperature. The set temperature of the first refrigerated showcase 12 is 10 ° C., the set temperature of the second refrigerated showcase 13 is 5 ° C., the set temperature of the third refrigerated showcase 14 is 2 ° C., and the set temperature of the freezer showcase 15. Is set to -20 ° C.

The outdoor unit 11 has an outdoor circuit 28, the first refrigerated showcase 12 has a first refrigerated circuit 25, the second refrigerated showcase 13 has a second refrigerated circuit 35, and a third refrigerated showcase. A third refrigeration circuit 45 is arranged in the showcase 14, a refrigeration circuit 55 is arranged in the freezing showcase 15, and a booster circuit 65 is arranged in the booster unit 16, respectively.

The booster circuit 65 is provided with a booster compressor 46. The refrigeration circuit 55 and the booster circuit 65 are connected in series. From the inlet 53 of the refrigerating circuit 55 to the outlet 54 of the booster circuit 65, a two-stage compression side circuit 47 is formed.

In the refrigerating device 30, these refrigerating circuits 25, 35, 45 and the two-stage compression side circuit 47 are connected to the liquid side connection pipe 18 and the gas side connection pipe 19 with respect to the outdoor circuit 28. By this, the refrigerant circuit 20 is connected in parallel with each other. Each refrigerated display case (12, 13, 14) constitutes a single-stage compression side use unit, the freezing showcase (15) constitutes a two-stage compression side use unit.

In the outdoor circuit 28, a compressor 29 and an outdoor heat exchanger 17 are provided. The compressor 29 is a hermetic and high pressure dome scroll compressor. In this compressor 29, the sucked refrigerant is compressed and discharged. The outdoor heat exchanger 17 is a cross fin fin tube type heat exchanger and constitutes a heat source side heat exchanger. In this outdoor heat exchanger (17), heat exchange is performed between the refrigerant and outdoor air. In the outdoor unit 11, the refrigerant pressure at the inlet of the compressor 29 is approximately equal to the refrigerant pressure at the inlet 61 of the outdoor unit 11, and the refrigerant pressure at the outlet of the outdoor heat exchanger 17 is the outlet of the outdoor unit 11. It is approximately equal to the refrigerant pressure of (71).

In each of the refrigerating circuits 25, 35, and 45, refrigerating expansion valves 22, 32, and 42 and refrigerating heat exchangers 21, 31, and 41 are arranged in order from the liquid end to the gas end. The refrigerating heat exchanger (21, 31, 41) is a cross fin fin tube type heat exchanger, constitutes a cooling heat exchanger, and cools the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. In these refrigerating heat exchangers (21, 31, 41), heat exchange is performed between the refrigerant and the reservoir air, respectively. On the other hand, the refrigeration expansion valve (22, 32, 42) is composed of an electromagnetic expansion valve.

In the first refrigerating showcase 12, the refrigerant pressure at the inlet of the refrigerating expansion valve 22 is approximately equal to the refrigerant pressure at the inlet 23 of the first refrigerating showcase 12, and the refrigerant pressure at the outlet of the refrigerating heat exchanger 21 is It is approximately equal to the refrigerant pressure at the outlet 24 of the first refrigerated showcase 12. In the second refrigerating showcase 13, the refrigerant pressure at the inlet of the refrigerating expansion valve 32 is approximately equal to the refrigerant pressure at the inlet 33 of the second refrigerating showcase 13, and the refrigerant at the outlet of the refrigerating heat exchanger 31. The pressure is approximately equal to the refrigerant pressure at the outlet 34 of the second refrigerated showcase 13. In the third refrigerating showcase 14, the refrigerant pressure at the inlet of the refrigerating expansion valve 42 is approximately equal to the refrigerant pressure at the inlet 43 of the third refrigerating showcase 14, and the refrigerant at the outlet of the refrigerating heat exchanger 41 is used. The pressure is approximately equal to the refrigerant pressure at the outlet 44 of the third refrigerated showcase 14.

In the refrigerating circuit 55, the refrigerating expansion valve 52 and the refrigerating heat exchanger 51 are arranged in order from the liquid end to the gas end. The refrigeration heat exchanger (51) is a cross fin fin tube type heat exchanger, which constitutes a cooling heat exchanger, and cools the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. In this freezer heat exchanger (51), heat exchange is performed between the refrigerant and the reservoir air. On the other hand, the refrigeration expansion valve 52 is composed of an electromagnetic expansion valve.

The booster compressor 46 of the booster unit 16 is a hermetic and high pressure dome scroll compressor, and its inlet is connected to the outlet of the refrigeration heat exchanger 51 of the refrigerating circuit 55. The booster compressor 46 compresses and discharges the refrigerant sucked from the freezer heat exchanger 51.

In the two-stage compression-side circuit 47 from the inlet 53 of the freezing showcase 15 to the outlet 54 of the booster unit 16, the refrigerant pressure at the inlet of the refrigeration expansion valve 52 is the two-stage compression-side circuit 47. The refrigerant pressure at the outlet of the booster compressor 46 is approximately equal to the refrigerant pressure at the outlet 54 of the two-stage compression-side circuit 47.

The liquid side connection pipe 18 has three branching points 72, 73, and 74 where two connection pipes are branched, and the branched connection pipes are each of the refrigerated showcases 12, 13, and 14 and the two-stage compression side circuit. It is connected to the inlets 23, 33, 43, 53 of the 47. Here, each branch point is the first branch point 72, the second branch point 73, and the third branch point 74 from the side closer to the outdoor unit 11.

The liquid side connection pipe 18 is the main pipe 1 from the outlet 71 of the outdoor unit 11 to the first branch point 72, and the first from the first branch point 72 to the second branch point 73. Connection pipe 2a, from the second branch point 73 to the third branch point 74, the second connection line 2b, from the first branch point 72 to the inlet 53 of the two-stage compression side circuit 47 Second branch piping 3b from the first branch pipe 3a, the second branch point 73 to the inlet 43 of the third refrigerated showcase 14, and the second refrigerated showcase 13 at the third branch point 74. The third branch pipe 3c to the inlet 33 and the fourth branch pipe 3d to the inlet 23 of the first refrigerated showcase 12 at the third branch point 74 are formed. That is, in the liquid side connection pipe 18 which is the discharge side connection pipe from the outdoor unit 11 outlet 71, the two-stage compression side circuit 47 is connected most upstream, and the three refrigerated showcases 12, 13, 14), the third refrigerated display case 14 having the lowest set temperature in the reservoir is connected to the most upstream side.

The gas side connection pipe 19 has three confluence points 65, 66, and 67 where two connection pipes join, and the connection pipes joined to each of the refrigerated showcases 12, 13, 14 and the two-stage compression side. It is connected to the outlets 24, 34, 44, 54 of the circuit 47. Here, each joining point is the first joining point 65, the second joining point 66, and the third joining point 67 from the side closer to the outdoor unit 11.

The gas side connection pipe 19 is a main pipe 4 from the first confluence point 65 to the inlet 61 of the outdoor unit 11, and a third from the first confluence point 65 to the second confluence point 66. Connection pipe 5a, the fourth connection pipe 5b from the second confluence point 66 to the third confluence point 67, from the outlet 54 of the two-stage compression side circuit 47 to the third confluence point 67. The second conduit pipe 6b from the first confluence pipe 6a, the third refrigerated showcase 14 outlet 44 to the first confluence point 65, and the second at the outlet 34 of the second refrigerated showcase 13 A third confluence pipe 6c to the confluence point 66 and a fourth confluence pipe 6d from the outlet 24 of the first refrigerated showcase 12 to the third confluence point 67. That is, in the gas side connecting pipe 19 which is the return side connecting pipe to the inlet 61 of the outdoor unit 11, the two-stage compression side circuit 47 is connected to the most upstream, and the three refrigerated showcases 12, Among the 13 and 14, the third refrigerated display case 14 having the lowest set temperature in the reservoir is connected to the downstream side.

Here, the length of the connecting pipe from the outlet 24 of the first refrigerating showcase 12 to the inlet 61 of the outdoor unit 11 is L1. This length L1 is the sum total of the lengths of the main pipe 4, the 3rd connection pipe 5a, the 4th connection pipe 5b, and the 4th confluence pipe 6d. The length of the connecting pipe from the outlet 34 of the second refrigerated display case 13 to the inlet 61 of the outdoor unit 11 is L2. This length L2 is the sum total of the lengths of the main pipe 4, the 3rd connection pipe 5a, and the 3rd confluence pipe 6c. The length of the connecting pipe from the outlet 44 of the third refrigerated display case 14 to the inlet 61 of the outdoor unit 11 is L3. This length L3 is the sum total of the length of the main piping 4 and the 2nd conduit piping 6b. The length of the connecting pipe from the outlet 54 of the two-stage compression side circuit 47 to the inlet 61 of the outdoor unit 11 is L4. This length L4 is the sum total of the lengths of the main pipe 4, the 3rd connection pipe 5a, the 4th connection pipe 5b, and the 1st conduit pipe 6a.

The lengths of the connecting pipes from the outlets 24, 34, 44, 54 of each of the refrigerated showcases 12, 13, 14 and the two-stage compression-side circuit 47 to the inlet 61 of the outdoor unit 11 are in descending order. , L3, L2, L1, L4. That is, the length of the connection pipe from the outlets 24, 34, 44 of each of the refrigerated showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is the length of the refrigerated showcase 12, The lower the set temperature of 13, 14), the shorter the configuration. In addition, the length of the connection piping from the outlet 54 of the two-stage compression-side circuit 47 to the inlet 61 of the outdoor unit 11 is the outlets 24, 34, 44 of the respective refrigerated showcases 12, 13, and 14. ) Is longer than any of the connection pipe 19 from the inlet 61 to the outdoor unit (11).

In this refrigerant circuit 20, the pipe diameters of the portions 4 to 6 in the gas side connecting pipe 19 on the return side are determined according to the refrigerant flow rate of each portion. As a result, the pressure loss of the refrigerant by the gas side connecting pipe 19 on the return side is almost equal in value per unit length in any connecting pipe. As a result, the pressure loss of the refrigerant caused by the return-side connecting pipe from the outlets 24, 34, 44 of the refrigerating showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is reduced. The shorter the length, the smaller. The lower the set temperature of the refrigerating showcases 12, 13, 14 to which the connection pipe is connected, the smaller. In addition, the pressure loss of the refrigerant due to the connection pipe from the outlet 54 of the two-stage compression-side circuit 47 to the inlet 61 of the outdoor unit 11 is reduced to the outlets of the respective cooling showcases 12, 13, 14 ( It is greater than any of the pressure loss of the refrigerant due to the connection pipe from the 24, 34, 44 to the inlet 61 of the outdoor unit (11).

Operation operation

The operation of the refrigerating device 30 of the present embodiment will be described. In this refrigerating device (30), the refrigerant circulates between the outdoor unit (11) and each of the cold showcases (12, 13, 14), and the cold heat exchangers (21, 31, 1) of each cold showcase (12, 13, 14). A single stage compression refrigeration cycle is executed using 41 as an evaporator, and refrigerant is circulated between the outdoor unit 11 and the two stage compression side circuit 47, and the cooling heat exchanger 51 of the refrigeration showcase 15 is used. The two stage compression refrigeration cycle is executed with the evaporator.

When the compressor 29 of the outdoor unit 11 is operated, the refrigerant compressed by the compressor 29 passes through the outdoor circuit 28 and flows into the outdoor heat exchanger 17. In the outdoor heat exchanger (17), the refrigerant radiates heat to the outdoor air to condense. The refrigerant condensed by the outdoor heat exchanger (17) leaves the outdoor unit (11) and flows into the main pipe (1) constituting the liquid side connection pipe (18). The refrigerant flowing into the main pipe 1 flows into each of the refrigerating circuits 25, 35, and 45 and the refrigerating circuit 55 from the branch points 72, 73, and 74.

The refrigerant flowing into each refrigeration circuit (25, 35, 45) is depressurized by each refrigeration expansion valve (22, 32, 42), and then introduced into each refrigeration heat exchanger (21, 31, 41). In each refrigeration heat exchanger (21, 31, 41), the refrigerant absorbs heat from the reservoir air and evaporates. In the first refrigerating showcase 12, the reservoir air cooled in the refrigerating heat exchanger 21 is supplied to the reservoir, and the reservoir temperature is maintained at approximately the set temperature (10 ° C). In the second refrigerator showcase 13, the reservoir air cooled in the refrigerator heat exchanger 31 is supplied to the reservoir, and the reservoir temperature is maintained at approximately the set temperature (5 ° C). In the third refrigerator showcase 14, the reservoir air cooled in the refrigerator heat exchanger 41 is supplied to the reservoir, and the reservoir temperature is maintained at approximately the set temperature (2 ° C). The refrigerant evaporated in each refrigeration heat exchanger (21, 31, 41) flows into each of the second to fourth confluence pipes (6b, 6c, 6d).

The refrigerant introduced into the refrigeration circuit 55 is decompressed by the refrigeration expansion valve 52 and then introduced into the refrigeration heat exchanger 51. In the freezer heat exchanger (51), the refrigerant absorbs heat from the reservoir air and evaporates. In the freezer showcase 15, the reservoir air cooled in the freezer heat exchanger 51 is supplied to the reservoir, and the reservoir temperature is maintained at approximately the set temperature (-20 ° C). The refrigerant evaporated in the freezer heat exchanger (51) flows into the booster circuit (65) from the freezer circuit (55). The refrigerant flowing into the booster circuit 65 is sucked into the booster compressor 46, and is compressed and discharged by the booster compressor 46. The refrigerant discharged from the booster compressor 46 flows into the first confluence pipe 6a.

The pressure loss of the refrigerant by the return side connecting pipe 19 from the outlets 24, 34, 44 of each of the refrigerated showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is the third refrigerated showcase. The value by the connecting piping from (14) is the smallest, followed by the second refrigerated showcase 13 and the first refrigerated showcase 12. Therefore, since the refrigerant evaporation temperature in each of the refrigerated showcases 12, 13, 14 is set in the order of the third refrigerated showcase 14, the second refrigerated showcase 13, and the first refrigerated showcase 12, In the refrigerated showcases 12, 13 and 14, the set temperature in the reservoir is maintained.

In the freezing showcase 15, the evaporation temperature of the coolant is set lower than that of the refrigerated showcases 12, 13, and 14, but the refrigerant from the freezing showcase 15 is discharged from the two-stage compression side circuit 47. The refrigerant pressure can be increased by compressing in the booster compressor 46 before reaching the temperature, so that the cooling showcase 15 has a high cooling capacity without affecting the evaporation temperature and the evaporation pressure of the refrigerating showcase 12, 13, 14. The storage can be cooled by exerting it.

The refrigerant flowing into the confluence pipes 6a, 6b, 6c, and 6d merges at the confluence points 65, 66, and 67, and flows through the main pipe 4 to the outdoor circuit 28. The refrigerant flowing into the outdoor circuit 28 is sucked into the compressor 29, compressed by the compressor 29, and discharged again. In the refrigerant circuit 20, the circulation of such refrigerant is repeated.

Effect of the first embodiment

In the first embodiment, the pressure of the refrigerant by the return side connecting pipe 19 from the outlets 24, 34, 44 of the respective refrigerated showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is reached. The loss becomes smaller as the set temperature of the refrigerating showcases 12, 13, 14 to which the connecting pipe 19 is connected is lower. As a result, the refrigerant evaporation temperature in each of the refrigerating showcases 12, 13, and 14 cooling heat exchangers 21, 31, and 41 is set so that the set temperature in the reservoir is lower than the set temperature in each reservoir. Since it can set low, the storage by the refrigerated showcases 12, 13, and 14 can be efficiently performed.

Further, in the first embodiment, the third refrigerated display case 14 having the lowest set temperature in the storage, which requires a higher cooling capacity than the other first and second refrigerated display cases 12 and 13, is a gas on the return side. In the side connection pipe (19), the refrigerant is easily returned to the outdoor unit (11), and in the liquid side connection pipe (18) on the discharge side, the refrigerant from the outdoor unit (11) is easily flowed in and connected. Compared with the first and second refrigerated display cases 12, 13, a large amount of refrigerant is configured to be easily distributed. Therefore, the 3rd refrigerated display case 14 can exhibit sufficient cooling capability in order to maintain the inside of a reservoir at a predetermined | prescribed set temperature.

In addition, in the said 1st Embodiment, even if the evaporation pressure and evaporation temperature of a refrigerant | coolant in the refrigeration showcase 15 are set to a value lower than the refrigerated showcase 12, 13, 14, the refrigerant from the refrigerated showcase 15 is, The refrigerant pressure can be increased by compressing in the booster compressor 46 before reaching the outlet 54 of the two-stage compression circuit 47. Therefore, the refrigerated showcase 15 can exhibit a higher cooling capacity than the refrigerated showcases 12, 13, 14 without affecting the evaporation temperature and the evaporation pressure of the refrigerated showcases 12, 13, 14.

Further, in the first embodiment, the refrigeration showcase 15 having the evaporation pressure and the evaporation temperature of the refrigerant set to a value lower than the refrigerated showcases 12, 13 and 14 has a refrigerant in the liquid side connection pipe 18 on the delivery side. It is connected in a state that is easy to flow in. Therefore, since a large amount of liquid refrigerant is easily introduced into the freezing showcase 15, it is possible to exhibit a sufficient cooling capacity to maintain the inside of the reservoir at a predetermined temperature.

Modification Example 1 of the First Embodiment

Modification Example 1 of the first embodiment will be described. This modified example 1 is the set temperature of the 1st refrigerated showcase 12 and the 2nd refrigerated showcase 13 in 1st Embodiment, and the thickness of the 4th connection piping 5b and the 4th conduit piping 6d ( Inside diameter).

In this modified example 1, the set temperature of the 1st refrigerated showcase 12 is 5 degreeC, and the set temperature of the 2nd refrigerated showcase 13 is 10 degreeC. The fourth connection pipe 5b and the fourth confluence pipe 6d have a sum of the refrigerant pressure loss caused by the fourth connection pipe 5b and the fourth confluence pipe 6d, and the third confluence pipe 6c. The thickness is determined to be smaller than the value by. As a result, the pressure loss of the refrigerant caused by the connecting pipe from the outlet 24 of the first refrigerated showcase 12 to the inlet 61 of the outdoor unit 11 is reduced to the outdoor unit at the outlet 34 of the second refrigerated showcase 13. (11) It becomes smaller than the pressure loss value of the refrigerant caused by the connecting pipe leading to the inlet 61. As a result, the pressure loss of the refrigerant caused by the gas side connecting pipe 19 from the outlets 24, 34, 44 of the refrigerating showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11, As in the first embodiment, the lower the set temperature of the refrigerating showcases 12, 13, 14 to which the connecting pipe 19 is connected, the smaller the value becomes.

According to this modification 1, the length of the return side connecting pipe 19 from the outlets 24, 34, 44 of each of the refrigerated showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is equal to this connection. Although the set temperatures of the refrigerated showcases 12, 13, and 14 to which the pipes 19 are connected are not short in order of being low, the chilled showcases 12, 13, and 14 are controlled by adjusting the thickness of the connection pipes 19. The pressure loss of the refrigerant caused by the connecting pipe 19 from the outlets 24, 34, 44 of the outlet to the inlet 61 of the outdoor unit 11, is the refrigerating showcase 12, 13 to which the connecting pipe 19 is connected. , 14) is set so that the set temperature is lowered in descending order. Therefore, regardless of the arrangement of the outdoor unit 11 or each of the refrigerated showcases 12, 13, 14, the inlet of the outdoor unit 11 at the outlets 24, 34, 44 of each of the refrigerated showcases 12, 13, 14. By adjusting the pressure loss of the refrigerant by the connecting pipe 19 leading to 61, the refrigerant evaporation temperature in each of the cold showcases 12, 13, and 14 cooling heat exchangers 21, 31, and 41 is stored in the respective reservoirs. The set temperature in the reservoir can be set in descending order so as to be a proper temperature with respect to the preset temperature, and the cooling of the reservoir by each of the refrigerator showcases 12, 13, and 14 can be performed efficiently.

Modification example 2 of the first embodiment

Modification 2 of the first embodiment will be described. The schematic block diagram of the refrigeration apparatus 30 of this modification 2 is shown in FIG. Unlike the first embodiment, the refrigerating device 30 does not include the freezing showcase 15 and the booster unit 16.

Specifically, the refrigerating device 30 of this modified example 2 includes an outdoor unit 11 and three refrigerated showcases 12, 13, and 14. Similarly to the first embodiment, in the liquid side connection pipe 18 which is the discharge side connection pipe from the outlet 71 of the outdoor unit 11, the set temperature in the reservoir is out of the three refrigerated showcases 12, 13 and 14; The lowest third refrigerated showcase 14 is connected to the most upstream side. Moreover, in the gas side connection pipe 19 which is the return side connection pipe which goes to the inlet 61 of the outdoor unit 11, it is the 3rd among the three refrigerated showcases 12, 13, 14 which the lowest set temperature in a storage is lowest. The refrigerated showcase 14 is connected to the most downstream side.

Second Embodiment

The refrigeration apparatus 30 which concerns on 2nd Embodiment of this invention is shown in FIG. In the refrigerating device 30, unlike the first embodiment, the two-stage compression-side circuit 47 is most downstream connected to the gas-side connecting pipe 19 on the return side. Hereinafter, the difference from 1st Embodiment is demonstrated concretely.

The gas side connection pipe 19 is a main pipe 4 from the first confluence point 65 to the inlet 61 of the outdoor unit 11, and a third from the first confluence point 65 to the second confluence point 66. Connection pipe 5a, fourth connection pipe 5b from the second confluence point 66 to the third confluence point 67, from the outlet 54 of the two-stage compression side circuit 47 to the first confluence point 65; Third confluence pipe 6b from the first confluence pipe 6a, the third refrigerated showcase 14 outlet 44 to the second confluence point 66, the third refrigeration showcase 13 outlet 34 A third confluence pipe 6c to the confluence point 67 and a fourth confluence pipe 6d to the third confluence point 67 from the outlet 24 of the first refrigerated showcase 12. That is, in the gas side connecting pipe 19, which is the return side connecting pipe to the inlet 61 of the outdoor unit 11, the two-stage compression side circuit 47 is connected to the downstream, and the three refrigerated showcases 12, Among the 13 and 14, the third refrigerated display case 14 having the lowest set temperature in the reservoir is connected to the downstream side.

The length of the connecting piping from the outlets 24, 34, 44 of each of the refrigerated display cases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is the refrigerated display case 12, 13, 14 to which the connecting piping is connected. The lower the set temperature, the shorter the configuration. In addition, the length of the connecting piping from the outlet 54 of the two-stage compression-side circuit 47 to the inlet 61 of the outdoor unit 11 is determined by the outlets 24, 34, 44 of the refrigerating showcases 12, 13, and 14, respectively. It is shorter than any of the connecting pipes 19 to the inlet 61 of the outdoor unit 11.

In this refrigerant circuit 20, in the gas side connecting pipe 19 on the return side, the tube diameter of each of the parts 4 to 6 is determined according to the refrigerant flow rate of each part. As a result, the pressure loss of the refrigerant by the gas side connecting pipe 19 on the return side becomes almost equal in value per unit length in any connecting pipe. As a result, the pressure loss of the refrigerant caused by the return side connecting pipe from the outlets 24, 34, 44 of each of the refrigerated showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is reduced. The shorter the length is, the smaller the temperature becomes, and the lower the set temperature of the refrigerating showcases 12, 13, and 14 to which the connection pipe is connected is smaller. In addition, the pressure loss of the refrigerant caused by the connecting pipe 19 from the outlet 54 of the two-stage compression side circuit 47 to the inlet 61 of the outdoor unit 11 is discharged from each of the refrigerated showcases 12, 13 and 14. It is smaller than any of the refrigerant pressure loss due to the connection pipe from (24, 34, 44) to the inlet 61 of the outdoor unit (11).

Effects of the Second Embodiment

In the second embodiment, as in the first embodiment, the return-side connecting pipe from the outlets 24, 34, 44 of the refrigerating showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11, respectively. The pressure loss of the refrigerant by (19) decreases as the set temperature of the refrigerating showcases 12, 13, 14 to which the connection pipe is connected is lower. As a result, the refrigerant evaporation temperature in each of the refrigerating showcases 12, 13, and 14 cooling heat exchangers 21, 31, and 41 is set so that the set temperature in the reservoir is lower than the set temperature in each reservoir. Since it can set low, the storage by the refrigerated showcases 12, 13, and 14 can be efficiently performed.

Further, in the second embodiment, the outlets 24, 34, 44, 54 of the respective refrigerated showcases 12, 13, 14 and the two-stage compression side circuit 47 are connected to the inlet 61 of the outdoor unit 11; The pressure loss of the refrigerant by the gas-side connecting pipe 19 on the return side reaches a minimum because the value of the gas-side connecting pipe 19 on the return side connected to the freezing showcase 15 is minimized. Of the outlets 24, 34, 44, and 54 of the two-stage compression-side circuit 47, the outlet 54 of the two-stage compression-side circuit 47, is the lowest. As a result, the refrigerant pressure at the outlet 54 of the freezing showcase 15, that is, the discharge pressure of the booster compressor 46 can be suppressed to be low, and the inlet / outer pressure difference of the booster compressor 46 can be reduced. Therefore, the power consumption in the booster compressor 46 can be kept low.

Other Embodiments

In the above embodiment, in the liquid side connection pipe 18 on the delivery side or the gas side connection pipe 19 on the return side, the refrigeration showcase 15 is not disposed most upstream or downstream as in the above embodiment. You may arrange | position between the refrigerated showcases 12, 13, and 14.

Moreover, about the said embodiment, the set temperature in the storage cabinet of the refrigerated showcases 12, 13, and 14 may be the same. At this time, the pressure loss of the refrigerant caused by the return-side connection pipe from the outlets 24, 34, 44 of each of the cold storage showcases 12, 13, 14 to the inlet 61 of the outdoor unit 11 is almost equal. desirable.

In the above embodiment, four or more refrigerated showcases may be provided in the refrigerant circuit 20, or four or more units may be connected to the outdoor unit 11 in parallel.

In the above embodiment, an air conditioning unit may be provided in the refrigerant circuit 20. At this time, in the air conditioning unit, the liquid side connection pipe 18 and the gas side connection pipe 19 are preferably connected to the outdoor unit 11 by different connection pipes.

Here, the above embodiments are essentially preferred examples, and are not intended to limit the present invention, the application thereof, or the scope of use thereof.

As described above, the present invention is useful for a refrigerating device in which a plurality of use units are connected in parallel to a heat source unit.

Claims (9)

The compressor 29 is provided with a plurality of first-stage compression-side use units 12, 13, 14 having cooling heat exchangers 21, 31, and 41 for cooling the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. Equipped with one heat source unit 11 having a), In the refrigerant circuit 20 in which a plurality of first stage compression-side use units 12, 13, 14 are connected in parallel to the heat source unit 11 in a connection pipe 18, 19, the first stage compression side is used. In a refrigeration apparatus in which a refrigerant is circulated between the units (12, 13, 14) and the heat source unit (11) to perform a one-stage compression refrigeration cycle, Pressure loss of the refrigerant by the return side connecting pipe 19 from the outlets 24, 34, 44 of the first stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11; Is a refrigeration apparatus, characterized in that the value by the return-side connecting pipe connected to the lowest set temperature in the reservoir among the plurality of single-stage compression-side use units (12, 13, 14) is minimized. The compressor 29 is provided with a plurality of first-stage compression-side use units 12, 13, 14 having cooling heat exchangers 21, 31, and 41 for cooling the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. Equipped with one heat source unit 11 having a), In the refrigerant circuit 20 in which a plurality of first stage compression-side use units 12, 13, 14 are connected in parallel to the heat source unit 11 in a connection pipe 18, 19, the first stage compression side is used. In a refrigeration apparatus in which a refrigerant is circulated between the units (12, 13, 14) and the heat source unit (11) to perform a one-stage compression refrigeration cycle, Pressure loss of the refrigerant by the return side connecting pipe 19 from the outlets 24, 34, 44 of the first stage compression-side use units 12, 13, 14 to the inlet 61 of the heat source unit 11; Is a refrigeration apparatus, characterized in that the lower the set temperature in the reservoir of the first-stage compression-side use unit (12, 13, 14) to which the connection pipe is connected, the smaller the value. The compressor 29 is provided with a plurality of first-stage compression-side use units 12, 13, 14 having cooling heat exchangers 21, 31, and 41 for cooling the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. Equipped with one heat source unit 11 having a), In the refrigerant circuit 20 in which a plurality of first stage compression-side use units 12, 13, 14 are connected in parallel to the heat source unit 11 in a connection pipe 18, 19, the first stage compression side is used. In a refrigeration apparatus in which a refrigerant is circulated between the units (12, 13, 14) and the heat source unit (11) to perform a one-stage compression refrigeration cycle, The length of the connecting pipe from the outlets 24, 34, 44 of the first stage compression side using units 12, 13, 14 to the inlet 61 of the heat source unit 11 is the plurality of single stage compression side using units. A refrigeration apparatus characterized by the shortest return side connecting pipe connected to the lowest set temperature in the reservoir among (12, 13, 14). The compressor 29 is provided with a plurality of first-stage compression-side use units 12, 13, 14 having cooling heat exchangers 21, 31, and 41 for cooling the inside of the reservoir to maintain the inside of the reservoir at a predetermined set temperature. Equipped with one heat source unit 11 having a), In the refrigerant circuit 20 in which a plurality of first stage compression-side use units 12, 13, 14 are connected in parallel to the heat source unit 11 in a connection pipe 18, 19, the first stage compression side is used. In a refrigeration apparatus in which a refrigerant is circulated between the units (12, 13, 14) and the heat source unit (11) to perform a one-stage compression refrigeration cycle, The length of the connecting pipe from the outlets 24, 34, 44 of the one-stage compression-side use unit 12, 13, 14 to the inlet 61 of the heat source unit 11 is the first stage to which the connecting pipe is connected. Refrigerating apparatus, characterized in that the shorter the set temperature in the storage of the compression unit using unit (12, 13, 14). The method according to any one of claims 1 to 4, In the return side connecting pipe (19) connecting the outlets (24, 34, 44) of the first stage compression-side use units (12, 13, 14) and the heat source unit (11) inlet (61), A refrigeration apparatus, characterized in that the lowest set temperature in the reservoir is connected to the downstream side of the first-stage compression-side use unit (12, 13, 14). The method according to claim 5, In the outlet side connecting pipe 18 connecting the outlet 71 of the heat source unit 11 and the inlet 23, 33, 43 of each of the first-stage compression-side use units 12, 13, 14, the plurality of A refrigeration apparatus, characterized in that the lowest set temperature in the reservoir is connected to the upstream side of the first-stage compression-side use unit (12, 13, 14). The method according to any one of claims 1 to 4, Two-stage compression-side circuit in which the two-stage compression-side use unit 15 and the booster compressor 46 are connected in series to keep the reservoir at a predetermined set temperature. 47) In the refrigerant circuit 20, the two-stage compression side circuit 47, together with the one-stage compression side use unit 12, 13, 14, is connected to the heat source unit 11 to the connection pipe (18, 19) And a refrigerant is circulated between the two-stage compression side using unit (15) and the heat source unit (11) to perform a two-stage compression refrigeration cycle. The method according to claim 7, Return to connect the outlets 24, 34, 44, 54 and the heat source unit 11 inlet 61 of each of the first stage compression-side use unit 12, 13, 14 and the second stage compression-side circuit 47 In the side connecting pipe (19), the two-stage compression side circuit (47) is connected to the most upstream side. The method according to claim 8, Connecting the outlet 71 of the heat source unit 11 and the inlet 23, 33, 43, 53 of each one-stage compression-side use unit (12, 13, 14) and the two-stage compression-side circuit 47 In the delivery side connection piping (18), the two-stage compression side circuit (47) is connected to the most upstream side.

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