KR100381634B1 - Refrigerator - Google Patents

Abstract

A first refrigerant passage (20) having a first compressor (21) and an outdoor heat exchanger (23); a second refrigerant passage (30) having a second compressor (31) and a heat storage heat exchanger (32); The refrigeration circuit 1R which connected the expansion valve E4 and the 3rd refrigerant path 40 which has the indoor heat exchanger 42 is provided. The heat storage heat exchanger 32 has a plurality of passes. The refrigerant discharged from the first compressor 21 is classified into a plurality after condensing in the outdoor heat exchanger 23. On the other hand, the refrigerant discharged from the second compressor 31 is also classified into a plurality. Both refrigerants are joined by the classification and sent to each pass of the heat storage heat exchanger (32). Thereafter, the refrigerant is condensed in the heat storage heat exchanger (32), decompressed by the indoor expansion valve (E4), evaporated in the room heat exchanger (42) and returned to the first compressor (21) and the second compressor (31).

Description

Freezing device {REFRIGERATOR}

Conventionally, as a refrigeration apparatus, there is a heat storage type air conditioner as disclosed in Japanese Patent Laid-Open No. 3-28672. The air conditioner has a main passage connected in the order of a compressor, an outdoor heat exchanger, an outdoor expansion valve, an indoor expansion valve, and an indoor heat exchanger, and is stored in a heat storage tank for heat storage to exchange heat between the heat storage medium and the refrigerant. A heat exchanger is provided. The air conditioner is configured to perform a normal cooling operation not using heat storage, a heat storage cooling operation using heat storage, and the like.

In this normal cooling operation, the refrigerant discharged from the compressor is condensed in the outdoor heat exchanger, depressurized by the indoor expansion valve, and evaporated in the indoor heat exchanger to return to the compressor.

In one embodiment of the heat storage cooling operation, the refrigerant discharged from the compressor is condensed in the heat storage heat exchanger, and then depressurized by the indoor expansion valve, and evaporated in the indoor heat exchanger to return to the compressor.

In another aspect of the heat storage cooling operation, the refrigerant discharged from the compressor is condensed in the outdoor heat exchanger, then supercooled in the heat storage heat exchanger, and then depressurized by the indoor expansion valve, and evaporated in the indoor heat exchanger to return to the compressor. Is done.

As described above, in the above air conditioner, the use of heat storage reduces the condensation temperature and increases the refrigerant supercooling, thereby increasing the cooling capacity.

The present invention relates to a refrigerating device, and more particularly to a refrigerating device that condenses at two different temperatures.

1 is a refrigerant circuit diagram showing an embodiment of the present invention.

2 is a piping structure diagram showing a confluence of a liquid refrigerant and a gas refrigerant.

3 is a refrigerant circuit diagram showing a refrigerant circulation direction of heat storage operation during cooling;

4 is a refrigerant circuit diagram showing a refrigerant circulation direction of high load operation during cooling;

5 is a Moliere diagram showing refrigerant characteristics in high load operation.

6 is a Moliere diagram showing a comparative example of refrigerant characteristics in high load operation.

7 is a refrigerant circuit diagram showing a refrigerant circulation direction in low load operation during cooling;

8 is a refrigerant circuit diagram showing a refrigerant circulation direction in normal operation during heating.

9 is a refrigerant circuit diagram showing a refrigerant circulation direction of heat storage operation during heating.

10 is a refrigerant circuit diagram showing a refrigerant circulation direction in a heating operation.

In the above-described air conditioner, there is a problem that it cannot be limited to effectively use cold heat in the heat storage heat exchanger. Thus, an air conditioner with two temperature condensation has been proposed.

In this air conditioner, two compressors are installed. The first compressor is connected to the outdoor heat exchanger, and the second compressor is connected to the heat storage heat exchanger. The refrigerant discharged from the first compressor is condensed in the outdoor heat exchanger to be a liquid refrigerant, while the refrigerant discharged from the second compressor is condensed in the heat storage heat exchanger to be a liquid refrigerant. Both liquid refrigerants then join, depressurize with an indoor expansion valve, evaporate in an indoor heat exchanger and return to the compressor.

However, in the above air conditioner, the refrigerant is condensed in the outdoor heat exchanger and the heat storage heat exchanger, and then combined, so that the supercooling degree of the refrigerant is reduced. That is, since the refrigerant temperature at the outlet of the outdoor heat exchanger is high and the refrigerant temperature at the outlet of the heat storage heat exchanger is low, when both refrigerants are mixed, the supercooling degree becomes small, and thus the cooling ability cannot be sufficiently improved.

This invention is made | formed in view of this point, Comprising: It aims at using the two heat exchangers from which condensation temperature differs effectively, suppressing the fall of the supercooling degree of refrigerant | coolant, and aiming at expansion of capacity.

According to the present invention, the liquid refrigerant from the first heat exchanger 23 and the gas refrigerant from the second compressor 31 are respectively classified and joined to be supplied to the second heat exchanger 32.

Specifically, as shown in FIG. 1, the first solution includes a first refrigerant passage 20 having a first compressor 21 and a first heat exchanger 23, a second compressor 31, and a second row. A second refrigerant passage 30 having an exchanger 32, and a refrigerating circuit 1R to which the third refrigerant passage 40 having the expansion mechanism E4 and the third heat exchanger 42 are connected. After the refrigerant discharged from the first compressor 21 is condensed in the first heat exchanger 23, the refrigerant is discharged from the second compressor 31, and the refrigerant after the joining is transferred to the second heat exchanger 32. After condensing at a lower temperature than the first heat exchanger (23), the refrigerant is decompressed to the expansion mechanism (E4) and evaporated in the third heat exchanger (42) to return to the first compressor (21) and the second compressor (31). It aims at the refrigerant | coolant apparatus which performs a circulation at least. The second heat exchanger 32 also has a plurality of passes. In addition, the refrigerating circuit 1R divides the refrigerant condensed in the first heat exchanger 23 and the refrigerant discharged from the second compressor 31 into a plurality of the refrigerants during the refrigerant circulation, and joins them, respectively. The refrigerant is configured to flow in each pass of the second heat exchanger 32.

In addition, the second solution means in the first solution, the expansion mechanism (E9) so that the first refrigerant passage (20) of the refrigerating circuit (1R) to classify the refrigerant condensed in the first heat exchanger (23) after depressurizing ).

The third solution means that the first solution means that the first heat exchanger 23 is an air heat exchanger and the second heat exchanger 32 is a water heat exchanger.

In the first solution, the second heat exchanger 32 is housed in the heat storage tank 11 so as to condense the refrigerant by cold heat of the heat storage tank 11.

In the first solution, first, when the first compressor 21 and the second compressor 31 are driven, the high pressure gas refrigerant discharged from the first compressor 21 flows to the first heat exchanger 23. The gas refrigerant is condensed in the first heat exchanger 23 to become a liquid refrigerant. In particular, in the third solution, since the first heat exchanger 23 is an air heat exchanger, the gas refrigerant is condensed by heat exchange with air. Thereafter, the liquid refrigerant is classified into a plurality, and in the second solution, the pressure is reduced in the expansion mechanism E9 before being classified.

Subsequently, the classified liquid refrigerant is classified into a plurality of high-pressure gas refrigerant discharged from the second compressor 31, so that the liquid refrigerant and the gas refrigerant are respectively joined to form a two-phase refrigerant, and the two-phase refrigerant is the second heat exchanger. Flow each 32 passes. Since the second phase heat exchanger 32 is accommodated in the heat storage tank 11 in the fourth solution, the two-phase refrigerant is condensed by heat exchange with the heat storage refrigerant of the heat storage tank 11 to become a liquid refrigerant, and thus the third refrigerant passage 40 Flows).

Thereafter, the liquid refrigerant is depressurized by the expansion mechanism E4 and then evaporated in the third heat exchanger 42 to be a gas refrigerant. This gas refrigerant then returns to the first compressor 21 and the second compressor 31. This refrigerant circulation is repeated.

Therefore, according to the present invention, since the liquid refrigerant condensed in the first heat exchanger 23 and the gas refrigerant discharged from the second compressor 31 are respectively classified and joined, the refrigerant flows to the second heat exchanger 32 so that the refrigerant flows. Since the supercooling degree can be secured sufficiently, the ability to improve cooling and the like can be reliably achieved.

In particular, since the liquid refrigerant and the gas refrigerant are classified and combined, the liquid refrigerant and the gas refrigerant can be distributed at almost equal ratios and supplied to each pass of the second heat exchanger 32.

That is, if the liquid refrigerant and the gas refrigerant are to be classified after joining, the refrigerant after each classification has a large difference in the ratio of liquid and gas, for example, a path through which only the liquid refrigerant flows or a path through which only the gas refrigerant flows. As a result, for example, the entire ice of the heat storage tank 11 cannot be melted evenly.

On the other hand, in the present invention, since the ratio of the liquid refrigerant and the gas refrigerant in each pass of the second heat exchanger 32 can be made almost equal, the ice can be melted evenly and the efficiency of heat storage use can be improved. At the same time, since the coolant subcooling degree in each pass of the second heat exchanger 32 can be made substantially the same, the supercooling degree of the entire coolant can be increased, and the performance can be further improved.

If the liquid refrigerant is depressurized before dividing, the liquid refrigerant can be decompressed by one expansion mechanism E9 as compared with the case of depressurizing after dividing. As a result, an increase in the number of parts can be prevented.

In addition, when the second heat exchanger 32 is accommodated in the heat storage tank 11 to condense the refrigerant after condensing in the second heat exchanger 32, the cooling heat of the heat storage tank 11 can be efficiently used, resulting in excessive power consumption. It can certainly be avoided.

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

As shown in FIG. 1, the air conditioner 10 of this embodiment is a refrigeration apparatus provided with the heat storage tank 11, and is comprised by the multi-type provided with several indoor units 12, 12, ....

The air conditioner 10 includes a refrigeration circuit 1R having a first refrigerant passage 20, a second refrigerant passage 30, and a third refrigerant passage 40. The refrigeration circuit 1R further comprises a main circuit 1M composed of the first refrigerant passage 20 and the third refrigerant passage 40.

The first refrigerant passage 20 includes a three-way switching valve 22, an outdoor heat exchanger 23, an outdoor expansion valve E2, and a first opening / closing valve S2 from the discharge side of the first compressor 21. The refrigerant pipes 24 are connected in series. The outdoor heat exchanger 23 is composed of an air heat exchanger as a first heat exchanger.

The plurality of indoor units 12, 12,... Are connected to each other in parallel with the third refrigerant passage 40. The third refrigerant passage 40 is constituted by three-way switching valves 41 connected in series to a plurality of indoor units 12, 12,... The indoor unit 12 is configured by connecting an indoor expansion valve E4 which is an expansion mechanism and an indoor heat exchanger 42 which is a third heat exchanger in series. The indoor expansion valve (E4), the indoor heat exchanger (42), and the three-way switching valve (41) are connected by a refrigerant pipe.

One end of the third refrigerant passage 40 on the indoor expansion valve E4 side is connected to one end of the first on-off valve S2 side of the first refrigerant passage 20, and the third of the third refrigerant passage 40 is closed. One end of the direction switching valve 41 is connected to the suction side of the first compressor 21. The main circuit 1M, which is a closed circuit, is formed by the first refrigerant passage 20 and the third refrigerant passage 40.

In the second refrigerant passage 30, the second on-off valve S3, the heat storage heat exchanger 32, and the heat storage expansion valve E3 are connected in series on the discharge side of the second compressor 31. It is connected and comprised by. In addition, the suction side of the second compressor 31 is connected to the third refrigerant passage 40, and one end of the second refrigerant passage 30 toward the heat storage expansion valve E3 is connected to the first refrigerant passage 20. The connection point X of the third refrigerant passage 40 is connected.

The heat storage heat exchanger 32 is a second heat exchanger, and is configured as a water heat exchanger in which a heat storage medium such as water is stored in the heat storage tank 11 where the condensation temperature is lower than that of the outdoor heat exchanger 23. The heat storage tank 11 stores heat storage media such as water and brine. On the other hand, the heat storage heat exchanger 32 has a plurality of paths through which a refrigerant flows, although not shown, and generates ice on the surface of the heat exchanger to accumulate cold heat in the heat storage tank 11, while generating hot water to generate heat storage tank 11. Is configured to accumulate heat.

A connection pipe 50 is connected between the discharge side of the first compressor 21 of the first refrigerant passage 20 and the discharge side of the second compressor 31 of the second refrigerant passage 30, and the connection piping 50 is connected to the discharge side of the second refrigerant passage 30. The third on-off valve (S5) is installed.

One end of the suction pipe 60 is connected to the three-way switching valve 22 of the first refrigerant passage 20, and the other end of the suction pipe 60 is connected to both compressors 21 of the third refrigerant passage 40. 31) It is connected to the suction side. The three-way switching valve 22 is configured to communicate the outdoor heat exchanger 23 to either of the discharge and suction sides of the compressors 21 and 31.

One end of the high pressure pipe 70 is connected to the three-way switching valve 41 of the third refrigerant passage 40, and the other end of the high pressure pipe 70 is the second compressor of the second refrigerant passage 30. It is connected between 31 and the 2nd on-off valve S3.

One end Y of the low pressure pipe 80 is connected between the second open / close valve S3 of the second freezing passage 30 and the heat storage heat exchanger 32, and the low pressure pipe 80 is opened and closed. A valve S8 is provided and the other end is connected between the three-way switching valve 41 of the third refrigerant passage 40 and the suction side of both compressors 21 and 31.

A branch pipe 90 branches between the outdoor expansion valve E2 and the first open / close valve S2 in the first refrigerant passage 20. The branch pipe 90 is provided with a branch expansion valve E9 which is an expansion mechanism and is connected between the heat exchanger 32 for heat storage of the second refrigerant passage 30 and the connection point Y of the low pressure pipe 80. do.

As shown in FIG. 2, a splitter pipe 9a is provided at the connecting end (L portion in FIG. 1) of the second refrigerant passage 30 in the branch pipe 90 of the first refrigerant passage 20. . The fractionation pipe 9a is connected to a plurality of refrigerant pipes 9b, 9b, ... to classify the refrigerant from the outdoor heat exchanger 23 into a plurality.

On the other hand, as shown in FIG. 2, the header 3a is provided in the connection part (L part of FIG. 1) of the branch piping 90 of the 1st refrigerant path 20 in the said 2nd refrigerant path 30. As shown in FIG. . A plurality of refrigerant pipes 3b, 3b, ... are connected to this header 3a to classify the refrigerant from the second compressor 31 into a plurality. Refrigerant tubes 9b, 9b, ... of the dividing pipe 9a are connected to the refrigerant tubes 3b, 3b, ... of the header 3a, and the refrigerant tubes 3b, 3b, of this header 3a. 3b, ... are connected to each path of the heat exchanger 32 for heat storage. That is, each of the refrigerant pipes 9b, 3b, ... is classified after joining the liquid refrigerant from the outdoor heat exchanger 23 and the gas refrigerant from the second compressor 31.

The refrigeration circuit 1R performs at least the high load operation using the heat storage at the time of the cooling operation, the low load operation using the heat storage at the cooling operation, and the heat storage operation to accumulate the cooling heat. It is configured to perform normal operation not in use, utilization operation using heat storage, and heat storage operation for accumulating heat.

HVAC

Next, the operation of the above-described air conditioner 10 will be described for each operation state.

Heat storage operation during cooling

First, in the heat storage operation, as shown in FIG. 3, the two three-way switching valves 22 and 41 are switched toward the solid line in FIG. 3, and the second on-off valve S2 is opened, and the second on-off valve S3 is opened. ) Is switched to the closed state, the third on-off valve S5 is opened, and the fourth on-off valve S8 is open, the outdoor expansion valve E2 is all open, and the branch expansion valve ( With both E9) and the indoor expansion valve E4 closed, the heat storage expansion valve E3 is adjusted to a predetermined opening degree.

In this state, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor 21 and the second compressor 31 joins and flows to the outdoor heat exchanger 23 through the three-way switching valve 22. In this outdoor heat exchanger (23), the gas refrigerant is condensed by heat exchange with outdoor air to form a liquid refrigerant. The liquid refrigerant flows through the first open / close valve S2 and flows to the second refrigerant passage 30 through the connection point X without flowing through the branch pipe 90 through the outdoor expansion valve E2.

Thereafter, the liquid refrigerant is depressurized by the expansion valve E3 for heat storage, and then evaporated in the heat storage heat exchanger 32 to cool the heat storage medium to become a gas refrigerant. The gas refrigerant then flows through the low pressure pipe 80 and returns to the first compressor 21 and the second compressor 31. By repeating this refrigerant circulation, ice is generated on the surface of the heat exchanger, and cold heat is accumulated in the heat storage tank 11.

High load operation during cooling

This high load operation is a cooling operation using the above-described heat storage, and is the most characteristic operating aspect of the present invention as shown in FIG. In this high load operation, the two three-way switching valves 22 and 41 are switched toward the solid line in Fig. 4, with the first on-off valve S2 closed and the second on-off valve S3 open. 3 the switching valve S5 is closed and the fourth switching valve S8 is closed, and both the outdoor expansion valve E2 and the heat storage expansion valve E3 are opened, and the branch expansion valve is opened. E9 and the indoor expansion valve E4 are adjusted to a predetermined opening degree.

First, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor 21 flows to the outdoor heat exchanger 23 through the three-way switching valve 22. In this outdoor heat exchanger 23, the gas refrigerant is condensed by heat exchange with outdoor air to become a liquid refrigerant. The liquid refrigerant in the first refrigerant passage 20 flows to the branch pipe 90 through the outdoor expansion valve E2, and is depressurized to a predetermined pressure in the branch expansion valve E9 to flow to the flow pipe 9a.

Meanwhile, the high pressure gas refrigerant discharged from the second compressor 31 flows to the header 3a through the second on / off valve S3.

The liquid refrigerant in the first refrigerant passage 20 is classified into each refrigerant tube 9b, 9b, ... in the fractionation tube 9a. The gas refrigerant of the second refrigerant passage 30 is classified into the refrigerant tubes 3b, 3b, ... in the header 3a. Thereafter, the liquid refrigerant and the gas refrigerant are joined by the respective refrigerant tubes 9b, 9b, ... to become two-phase refrigerants, and flow through the respective paths of the heat exchanger 32 for heat storage. The two-phase refrigerant is condensed by heat exchange with the heat storage medium in the heat storage heat exchanger 32 to become a liquid refrigerant, and flows into the third refrigerant passage 40 through the heat storage expansion valve E3.

Subsequently, the liquid refrigerant flows through each indoor unit 12 to be decompressed by the indoor expansion valve E4, and then evaporates in the indoor heat exchanger 42 to become a gas refrigerant. The gas refrigerant then returns to the first compressor 21 and the second compressor 31 via the three-way switching valve 41. This refrigerant circulation is repeated to cool the room.

The refrigerant characteristics of the above-described refrigerant circulation will be described with the Moliere diagram of FIG. 5.

First, the high pressure gas refrigerant is discharged from the first compressor 21 at point A, and the high pressure gas refrigerant is condensed in the outdoor heat exchanger 23 to become the liquid refrigerant at point B. This liquid refrigerant is depressurized to the point C by the branch expansion valve E9.

On the other hand, the high pressure gas refrigerant is discharged from the second compressor 31 at point D, and the high pressure gas refrigerant (point D) and the liquid refrigerant (point C) of the first refrigerant passage 20 are joined to each other. It becomes a phase refrigerant.

This two-phase refrigerant is then condensed in the heat storage heat exchanger 32 to form a liquid refrigerant at point F. The liquid refrigerant is depressurized to the point G by the indoor expansion valve E4 and evaporated in the room heat exchanger 42 to form the gas refrigerant at the point H. The gas refrigerant is the first compressor 21 and the second compressor 31. Return to

Here, as a comparative example, the refrigerant characteristic of the refrigerant circulation in the case where the liquid refrigerant condensed in the outdoor heat exchanger 23 and the liquid refrigerant condensed in the heat storage heat exchanger 32 joins will be described with the Moliere diagram of FIG.

In this case, the liquid refrigerant condensed in the outdoor heat exchanger (23) flows to the connection point (X) without flowing through the branch pipe (90), and the liquid refrigerant condensed in the heat storage heat exchanger (32) at this connection point (X). Join with.

First, the refrigerant in the first refrigerant passage 20 discharges the high pressure gas refrigerant from the first compressor 21 (point A), condenses it in the outdoor heat exchanger 23 (point B), and moves it to the outdoor expansion valve E2. The pressure is reduced (point C). On the other hand, the refrigerant of the second refrigerant passage 30 is discharged from the second compressor 31 by the high-pressure gas refrigerant (point D), and condensed in the heat storage heat exchanger 32 (point I).

Thereafter, the two-phase refrigerant (point C) of the first refrigerant passage 20 and the liquid refrigerant (point I) of the second refrigerant passage 30 join to form a liquid refrigerant of point F. This liquid refrigerant is then depressurized by the indoor expansion valve E4 (point G), evaporated in the indoor heat exchanger 42 and returned to the first compressor 21 and the second compressor 31 (point H).

Therefore, in the comparative example of FIG. 6, the refrigerant discharged from the second compressor 31 is condensed and supercooled in the heat storage heat exchanger 32, but since the refrigerant condensed in the outdoor heat exchanger 23 joins, Subcooling degree becomes small (refer F point). On the other hand, in this embodiment shown in FIG. 5, since the refrigerant | coolant after joining is supercooled, refrigerant supercooling degree (point F) becomes large.

Low load operation at cooling

In this low load operation, as shown in Fig. 7, the two three-way switching valves 22 and 41 are switched to the solid line in Fig. 7, and the second on / off valve S2 is closed. In the state where S3) is closed, the third on-off valve S5 is opened, and the fourth on-off valve S8 is switched to the closed state, and the outdoor expansion valve E2 and the branch expansion valve E9 and the heat storage expansion With the valve E3 all open, the indoor expansion valve E4 is adjusted to a predetermined opening degree. Also in the low load operation, cold heat of the heat storage medium is accumulated in the heat storage tank 11.

First, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor 21 and the second compressor 31 joins and flows to the outdoor heat exchanger 23 via the three-way switching valve 22. In this outdoor heat exchanger (23), the gas refrigerant is condensed by heat exchange with outdoor air to form a liquid refrigerant. This liquid refrigerant flows through the outdoor expansion valve (E2) to the branch pipe (90), and is then supercooled by heat exchange with the heat storage medium in the heat storage heat exchanger (32). The liquid refrigerant after this subcooling flows to the third refrigerant passage 40 via the heat storage expansion valve E3.

Subsequently, the liquid refrigerant flows through each indoor unit 12, is reduced in pressure by the indoor expansion valve E4, and then evaporated in the indoor heat exchanger 42 to be a gas refrigerant. The gas refrigerant then returns to the first compressor 21 and the second compressor 31 via the three-way switching valve 41. This refrigerant circulation is repeated to cool the room.

Normal operation during heating

In this normal operation, as shown in FIG. 8, the two three-way switching valves 22 and 41 are switched toward the solid line in FIG. 8, and the second on-off valve S3 is opened while the first on-off valve S2 is open. Is closed, the third on-off valve (S5) is open, the fourth on-off valve (S8) is switched to the closed state, the indoor expansion valve (E4) is all open, the branch expansion valve (E9) and With the heat storage expansion valve E3 all closed, the outdoor expansion valve E2 is adjusted to a predetermined opening degree.

First, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor (21) and the second compressor (31) is joined, and the indoor heat exchanger is connected from the second refrigerant passage (30) via the high pressure pipe (70) and the three-way switching valve (41). Flows to (42). In this indoor heat exchanger (42), the gas refrigerant is condensed by heat exchange with indoor air to form a liquid refrigerant. This liquid refrigerant flows into the first refrigerant passage 20 through the indoor expansion valve E4.

Thereafter, the liquid refrigerant is depressurized by the outdoor expansion valve E2 via the first opening / closing valve S2, and then evaporated by heat exchange with outdoor air in the outdoor heat exchanger 23 to be a gas refrigerant. Thereafter, the gas refrigerant flows through the suction pipe 60 from the three-way switching valve 22 and returns to the first compressor 21 and the second compressor 31. This refrigerant circulation is repeated to heat the room.

Heat storage operation when heating

In this heat storage operation, as shown in FIG. 9, the two three-way switching valves 22 and 41 are switched toward the solid line in FIG. 9, and the second on-off valve S3 is opened while the first on-off valve S2 is opened. ) Is opened, the third on-off valve S5 is open, the fourth on-off valve S8 is switched to the closed state, and the expansion valve E3 for the heat storage is all open, the branch expansion valve E9. ) And the indoor expansion valve E4 are all closed, the outdoor expansion valve E2 is adjusted to a predetermined opening degree.

In this state, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor 21 and the second compressor 31 joins and flows through the second refrigerant passage 30 to the heat storage heat exchanger 32. In this heat storage heat exchanger (32), the gas refrigerant is condensed by heat exchange with the heat storage medium to become a liquid refrigerant. This liquid refrigerant flows to the connection point (X) through the heat storage expansion valve (E3) and flows to the first refrigerant passage (20).

Thereafter, the liquid refrigerant is depressurized by the outdoor expansion valve E2 via the first opening / closing valve S2, and then evaporated by heat exchange with outdoor air in the outdoor heat exchanger 23 to be a gas refrigerant. This gas refrigerant then flows through the suction pipe 60 from the three-way switching valve 22 and returns to the first compressor 21 and the second compressor 31. This refrigerant circulation is repeated to accumulate heat such as hot water in the heat storage tank 11.

-Driving operation when heating-

This use operation is a heating operation using the above-described heat storage, and as shown in FIG. 10, two three-way switching valves 22 and 41 are switched toward the solid line in FIG. 10, and the first on-off valve S2 is closed. The second on-off valve S3 is closed, the third on-off valve S5 is open, the fourth on-off valve S8 is switched to an open state, and the indoor expansion valve E4 is all open. The thermal expansion valve E3 is adjusted to a predetermined opening degree in a state where both the branch expansion valve E9 and the outdoor expansion valve E2 are closed.

First, the first compressor 21 and the second compressor 31 are driven. The high pressure gas refrigerant discharged from the first compressor (21) and the second compressor (31) is joined, and the indoor heat exchanger is connected from the second refrigerant passage (30) via the high pressure pipe (70) and the three-way switching valve (41). Go to 42. In this indoor heat exchanger (42), the gas refrigerant is condensed by heat exchange with indoor air to form a liquid refrigerant. This liquid refrigerant flows into the second refrigerant passage 30 through the indoor expansion valve E4.

Thereafter, the liquid refrigerant is depressurized by the expansion valve E3 for heat storage, and is then evaporated by heat exchange with the heat storage medium in the heat storage heat exchanger 32 to be a gas refrigerant. This gas refrigerant then flows through the low pressure pipe 80 and returns to the first compressor 21 and the second compressor 31. This refrigerant circulation is repeated to heat the room.

Effect of Embodiments

As described above, according to the present embodiment, the liquid refrigerant condensed in the outdoor heat exchanger 23 and the gas refrigerant discharged from the second compressor 31 are classified, and then joined by each classification to the heat storage heat exchanger 32. Since the flow rate of the refrigerant can be sufficiently secured, the cooling capacity can be reliably improved.

In particular, since the liquid refrigerant and the gas refrigerant are classified and joined, the liquid refrigerant and the gas refrigerant can be distributed in almost equal ratios and supplied to each pass of the heat exchanger 32 for heat storage.

In other words, if the liquid refrigerant and the gas refrigerant are to be classified after joining, the refrigerant after each classification has a large ratio of liquid and gas, for example, a path through which only the liquid refrigerant flows or a path through which only the gas refrigerant flows. As a result, the entire ice of the heat storage tank 11 cannot be melted evenly.

On the other hand, in this embodiment, since the ratio of the liquid refrigerant and the gas refrigerant in each pass of the heat storage heat exchanger 32 can be made almost the same, the ice melts evenly and the efficiency of heat storage use can be improved. At the same time, since the coolant subcooling degree in each path of the heat storage heat exchanger 32 can be made almost the same, the supercooling degree of the entire coolant can be increased, and the performance can be further improved.

In addition, since the liquid refrigerant is to be depressurized before the fractionation, it can be reduced by one branch expansion valve E9 as compared with the case where the liquid refrigerant is depressurized after the fractionation. As a result, an increase in the number of parts can be prevented.

In addition, when condensing the refrigerant after the condensation in the heat storage heat exchanger 32, the cooling heat of the heat storage tank 11 can be efficiently used, so that excessive power consumption can be reliably prevented.

Another embodiment of the invention

In the above embodiment, the heating operation is performed in addition to the cooling operation. However, in the present invention, only the cooling operation may be performed, or only the refrigerant circulation of the high load operation during cooling of the present embodiment may be performed.

In addition, the present invention is not limited to the air conditioner 10, and may be a so-called two-temperature condensation operation having different condensation temperatures, and may be various refrigeration apparatuses applied to a freezer or the like.

Therefore, the first heat exchanger 23 is not necessarily limited to the air heat exchanger, and the second heat exchanger 32 is not limited to the water heat exchanger or the heat storage heat exchanger. In addition, the third heat exchanger 42 is not limited to the indoor heat exchanger.

In the present embodiment, the number of classification of the first refrigerant passage 20 and the second refrigerant passage 30 is the same. That is, the refrigerant pipes 9b, 9b, ... of the flow dividing pipe 9a in the first refrigerant passage 20 and the refrigerant pipes 3b, 3b,... Of the header 3a in the second refrigerant passage 30. Do the same.

However, in the present invention, the refrigerant pipes 9b, 9b, ... of the flow pipe 9a and the refrigerant pipes 3b, 3b, ... of the header 3a may be different. That is, the refrigerant pipes 9b, 9b, ... of the flow pipe 9a may be larger than the refrigerant pipes 3b, 3b, ... of the header 3a, and conversely, the refrigerant pipe 3b of the header 3a. , 3b, ... may be made larger than the refrigerant pipes 9b, 9b, ... of the flow pipe 9a. In short, liquid and gas refrigerants can be classified into several groups and joined by several.

In addition, the number of passes of the heat storage heat exchanger 32 may be larger than the number of the refrigerants classified, or vice versa. That is, the number of passes may be larger than the number of coolant tubes 3b, 3b, ... of the header 3a in the present embodiment, or vice versa. In short, the refrigerant that has been joined at some number may flow through a plurality of paths.

As described above, the refrigerating device according to the present invention is useful when condensing the refrigerant at two temperatures, and is particularly suitable for a refrigerating device having a heat storage tank.

Claims (4)

A first refrigerant passage (20) having a first compressor (21) and a first heat exchanger (23), a second refrigerant passage (30) having a second compressor (31) and a second heat exchanger (32), A refrigeration circuit (1R) to which a third refrigerant passage (40) having an expansion mechanism (E4) and a third heat exchanger (42) is connected; After the refrigerant discharged from the first compressor 21 is condensed in the first heat exchanger 23, the refrigerant is discharged from the second compressor 31, and the refrigerant after the joining is transferred from the second heat exchanger 32. After condensing at a lower temperature than the first heat exchanger 23, the pressure is reduced by the expansion mechanism E4 and evaporated in the third heat exchanger 42 to return to the first compressor 21 and the second compressor 31. A refrigerant device for performing at least While the second heat exchanger 32 has a plurality of passes, The refrigerant circuit 1R divides the refrigerant condensed in the first heat exchanger 23 and the refrigerant discharged from the second compressor 31 into a plurality of refrigerants during the refrigerant circulation, and joins them, respectively. Refrigeration apparatus configured to flow in each pass of the second heat exchanger (32). The method of claim 1, The first refrigerant passage (20) of the refrigerating circuit (1R) is provided with an expansion mechanism (E9) for dividing the refrigerant condensed in the first heat exchanger (23) after decompression. The method of claim 1, Refrigeration apparatus wherein the first heat exchanger (23) is an air heat exchanger and the second heat exchanger (32) is a water heat exchanger. The method of claim 1, The second heat exchanger (32) is stored in the heat storage tank (11) is configured to condense the refrigerant by the cold heat of the heat storage tank (11).