JPH09250824A - Heat source apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compensate capability when an air conditioner is required for more capability than maximum capability by providing a freezing cycle independent from the air conditioner to which an outdoor machine and a plurality of indoor machines are connected and a heat exchanger disposed in the freezing cycle, and cooling a liquid refrigerant fed from the outdoor machine to the indoor machines with the heat exchanger. SOLUTION: A high pressure gas refrigerant from a compressor 11 passes through a four-way valve 12 and flows to an outdoor heat exchanger 13 where it is heat exchanged with outdoor air and is condensed into a liquid refrigerant. The liquid refrigerant enters an indoor heat exchanger 17 and is heat exchanged with indoor air. The refrigerant is changed to a low pressure gas refrigerant and is sucked into the compressor 11 after passage through a gas pipe 9 and the four-way valve 12. When upon such cooling operation a cold heat source for cooling a liquid refrigerant for an air conditioner is supplied to heat exchangers 21, 22, the cold heat source and the liquid refrigerant are heat exchanged, and hence supercooling of the liquid refrigerant is increased. Hereby, specific enthalpy of the liquid refrigerant is reduced and results in an increase of refrigerant vaporization latent heat and an increase of cooling capability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improving the capacity of an air conditioner using a refrigeration cycle.

[0002]

2. Description of the Related Art As a method for improving the capacity of an air conditioner and cutting power peaks in summer, there is a method of cooling a liquid refrigerant.
For example, in JP-A-1-174866, a heat storage tank is provided in an air conditioner, a refrigeration cycle circuit for applying cold heat to a heat storage medium in the heat storage tank, and a heat exchanger for cooling a liquid refrigerant are provided for air conditioning. When not in use, the heat is stored in the heat storage medium of the heat storage tank, and when air conditioning is performed, the liquid refrigerant is cooled through the heat storage tank,
It has improved capacity and cuts power peaks. Further, as another example, in JP-A-63-204076, a cooling circuit is branched from a certain outdoor unit, and the cooling circuit is provided on the liquid refrigerant side of another outdoor unit to guide it to a heat exchanger, and The liquid refrigerant of the outdoor unit can be cooled, and the liquid refrigerant of the outdoor unit, which is required to have a capacity higher than the maximum capacity, can be cooled by another outdoor unit having a surplus supply capacity so that the capacity can be compensated.

[0003]

When the capacity of a certain outdoor unit is compensated by another outdoor unit as described above, there is a drawback that it cannot be compensated when the supply capacity of another outdoor unit is not sufficient.

It is an object of the present invention, even when only a part of a plurality of air conditioners is required to have a capacity higher than the maximum capacity, or when all air conditioners are required to have a capacity higher than the maximum capacity. It is to provide a cold heat source device capable of compensating for capacity.

In the air conditioner equipped with a heat storage tank,
Since the heat storage is performed when the air conditioner is not operating, the effect of improving the capacity cannot be obtained when the heat storage is lost.
Furthermore, when the number of outdoor units is large, the number of heat storage tanks is also large, and a large space is required. Another object of the present invention is to provide an air conditioner capable of storing heat even when the air conditioner is operating, and to reduce the number of heat storage tanks to save space.

[0006]

In order to achieve the above object, a cold heat source device according to the present invention comprises a refrigeration cycle independent of an air conditioner in which an outdoor unit and a plurality of indoor units are combined,
A heat exchanger provided in the refrigeration cycle is provided, and the liquid refrigerant sent from the outdoor unit to the indoor unit is cooled by the heat exchanger.

Further, the cold heat source device according to the present invention has a heat exchanger and a heat storage tank independent of the air conditioner, and heats the liquid refrigerant of the air conditioner by the heat exchanger.

Further, in order to compensate the capacity of a part of the plurality of air conditioners or to compensate the capacity of all the air conditioners, a cold heat source device is provided separately from the air conditioner, and a heat exchanger is installed in the liquid pipe of the air conditioner. The heat exchanger enables heat exchange between the liquid refrigerant of the air conditioner and the cold heat medium from the cold heat source device.

Further, the heat storage tank is provided in the cold heat source device, and the heat storage medium in the heat storage tank cools or heats the liquid refrigerant of each air conditioner with the heat exchanger provided in the liquid pipe. Cold storage or heat storage of the heat storage medium in the heat storage tank is performed by the cooling and heating means in the cold heat source device.

Further, a cooling and heating means for cooling the heat storage medium in the heat storage tank branches the refrigerant circuit of the air conditioner, a heat exchanger is provided in the heat storage tank, and the branched refrigerant circuit and the heat exchanger are connected to form a refrigeration cycle. The heat storage medium is configured to be cooled and heated.

The following operations are performed by exchanging heat between the liquid refrigerant in the liquid pipe of the air conditioner and the cold heat source from the cold heat source device by the heat exchanger installed in the liquid pipe. When the air conditioner is in cooling operation, by supplying a cold heat source that cools the liquid refrigerant from the cold heat source device, the degree of supercooling of the liquid refrigerant increases, the specific enthalpy of the refrigerant in front of the expansion valve decreases, and The latent heat of vaporization increases and the cooling capacity of the air conditioner increases. Further, during heating operation, by supplying a cold heat source that heats the liquid refrigerant from the cold heat source device, the degree of supercooling of the liquid refrigerant is decreased, or the degree of dryness is increased and the ratio of the refrigerant before the expansion valve is increased. The enthalpy increases, and the refrigerant superheat degree at the evaporator outlet increases. Here, since the expansion valve opens so that the refrigerant superheat degree at the evaporator outlet becomes a predetermined value, the evaporation pressure increases. As a result, the specific volume of the compressor suction refrigerant is reduced, and the refrigerant circulation amount is increased. Further, as the suction pressure rises, the discharge pressure and the condensing pressure also rise, and the heating capacity increases.

By providing the heat storage tank in the cold heat source device and supplying the heat storage medium that stores or stores the heat to the heat exchanger provided in the liquid pipe of each air conditioner, the above-mentioned improvement of the capacity of the air conditioner can be realized. At the same time, since it is not necessary to provide a heat storage tank in each air conditioner, the number of heat storage tanks is reduced and space is saved. Also,
Cooling / heating means in the cold heat source device for storing the cold heat of the heat storage tank, or
This can be done by the refrigeration cycle branched from the air conditioner, and cool heat can be stored even when the air conditioner is operating.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of the present invention is shown in FIGS. In FIG. 1, an air conditioner in which an outdoor unit 1 and an indoor unit 3 are connected by a liquid pipe 7 and a gas pipe 9, and an outdoor unit 2 and three indoor units 4, 5, 6 are a liquid pipe 8 and a gas pipe. Two air conditioners are shown, combined at 10. The outdoor unit 1 is the compressor 1
1, a four-way valve 12, an outdoor heat exchanger 13, a control valve 14, and an outdoor fan 15. The indoor unit 3 has a control valve 16,
It is composed of an indoor heat exchanger 17 and an indoor fan 18.
The outdoor unit 2 and the indoor units 4, 5, 6 have the same configurations as the outdoor unit 1 and the indoor unit 3. Heat exchangers 21 and 22 are attached to the respective liquid pipes of the two air conditioners. In addition to the liquid pipes 7 and 9, pipes 26 and 25 are connected to the heat exchangers 21 and 22 via control valves 23 and 24, respectively. The pipe 25 and the pipe 26 are connected to the cold heat source device 20.

Next, the operation will be described. During the cooling operation of the air conditioner, the refrigerant flows in the direction of the solid arrow. Compressor 11
The high-pressure gas refrigerant discharged from the refrigerant flows through the four-way valve 12 to the outdoor heat exchanger 13 and is heat-exchanged with the outdoor air by the outdoor fan 15 to be condensed and become a liquid refrigerant. The liquid refrigerant flows through the liquid pipe 7 through the control valve 14 having a large opening degree and is sent to the indoor unit 3. In the indoor unit 3, the liquid refrigerant is decompressed by the control valve 16 having a small opening degree, enters the indoor heat exchanger 17, and is heat-exchanged with the indoor air by the indoor fan 18. At this time, the indoor air is cooled, the refrigerant evaporates and becomes a low-pressure gas refrigerant, and returns to the outdoor unit 1 through the gas pipe 9. The low-pressure gas refrigerant returned to the outdoor unit 1 is sucked into the compressor 11 through the four-way valve 12. This refrigerant state is shown on the Mollier diagram as shown by the solid line in FIG. The outdoor unit 2 and the three indoor units 4, 5,
The air-conditioning operation of the air conditioner 6 is the same as above. In such a cooling operation, when a cold heat source that cools the liquid refrigerant of the air conditioner is supplied from the cold heat source device 20 to the heat exchange units 21 and 22, the cold heat source and the liquid refrigerant exchange heat and the liquid refrigerant is supercooled. As the degree increases, it becomes like the broken line on the Mollier diagram of FIG.
That is, as the degree of supercooling of the liquid refrigerant in the air conditioner increases, the specific enthalpy of the liquid refrigerant decreases, the latent heat of vaporization of the refrigerant increases, and the cooling capacity also increases. During heating operation, the refrigerant flows as indicated by the broken line arrow. The high-pressure gas refrigerant discharged from the compressor 11 flows into the gas pipe 9 through the four-way valve 12 and enters the indoor unit 3. In the indoor unit 3, the indoor heat exchanger 17 exchanges heat with the indoor air by the indoor fan 18, the indoor air is warmed, and the refrigerant is condensed into a liquid refrigerant. The liquid refrigerant flows through the control valve 16 having a large opening to the liquid pipe 7 and is sent to the outdoor unit 1. In the outdoor unit 1, the liquid refrigerant is decompressed by the control valve 14 having a small opening degree, enters the outdoor heat exchanger 13, is heat-exchanged with the outdoor air by the outdoor fan 15, and the refrigerant evaporates to become a low-pressure gas refrigerant. And is sucked into the compressor 11 through the four-way valve 12. Outdoor unit 2 and three indoor units 4, 5, 6
The heating operation of the air conditioner is also the same as described above. The refrigerant state during heating operation is shown on the Mollier diagram as shown by the solid line in FIG. During such heating operation, the cold heat source device 20
When a cold heat source that heats the liquid refrigerant of the air conditioner is supplied to the heat exchangers 21 and 22, the cold heat source and the liquid refrigerant exchange heat,
The degree of supercooling of the liquid refrigerant decreases or the degree of dryness increases, which is indicated by the broken line on the Mollier diagram of FIG. That is, the supercooling degree of the liquid refrigerant of the air conditioner decreases, or the dryness increases, the specific enthalpy of the liquid refrigerant decreases, the latent heat of vaporization of the refrigerant decreases, and the superheat degree of the outdoor heat exchanger 13 outlet, Or, since the compressor discharge gas superheat becomes large,
The opening degree of the control valve 14 is increased so that the superheat degree becomes the original value. As a result, the evaporation pressure rises, the specific volume of the compressor suction refrigerant decreases, and the refrigerant circulation amount increases.
Along with this, the discharge pressure increases. This increases the heating capacity.

Next, an embodiment of the cold heat source device 20 is shown in FIG. In FIG. 4, the cold heat source device 20 includes a compressor 30, a four-way valve 31, a heat exchanger 32, a control valve 33, and a fan 34. When cooling the liquid refrigerant of the air conditioner, the four-way valve 31 is set as indicated by the solid line. The high-pressure gas refrigerant discharged from the compressor 30 passes through the four-way valve 31 and is passed through the heat exchanger 32.
And the heat is exchanged with the outdoor air by the fan 34, the refrigerant condenses into a liquid refrigerant, and the control valve 3 having a large opening
3 to the pipe 26. The liquid refrigerant is decompressed from the pipe 26 through the control valves 23 and 24 having a small opening degree, enters the heat exchangers 21 and 22, and exchanges heat with the liquid refrigerant of the air conditioner. At this time, the liquid refrigerant of the air conditioner is cooled and the degree of supercooling is increased. The refrigerant sent from the cold heat source device 20 evaporates to become a low-pressure gas refrigerant, passes through the pipe 25, and is cooled by the cold heat source device 20.
And is sucked into the compressor 30 through the four-way valve 31.
When the liquid refrigerant of the air conditioner is overheated, the four-way valve 31 is switched as shown by the broken line. The high-pressure gas refrigerant discharged from the compressor 30 flows into the pipe 25 through the four-way valve 31, and the heat exchanger 2
It enters into 1 and 22 and is heat-exchanged with the liquid refrigerant of an air conditioner. At this time, the liquid refrigerant of the air conditioner is heated and the degree of supercooling is reduced. Or, the dryness increases. The refrigerant sent from the cold heat source device 20 is condensed to become a liquid refrigerant. The liquid refrigerant flows into the pipe 26 through the control valves 23 and 24 having a large opening degree and returns to the cold heat source device 20. The liquid refrigerant that has entered the cold heat source device 20 is decompressed by the control valve 33 having a small opening degree, enters the heat exchanger 32, is heat-exchanged with the outdoor air by the fan 34, evaporates, and becomes a low-pressure gas refrigerant and becomes the four-way valve 31. And is sucked into the compressor 30. Here, the flow rate of the cold heat source flowing to the heat exchangers 21 and 22 can be adjusted by adjusting the opening degrees of the control valves 23 and 24.

Another embodiment of the cold heat source device 20 is shown in FIG. In FIG. 5, the cold heat source device 20 includes a compressor 30, a four-way valve 31, a heat exchanger 32, a control valve 33, a fan 34, a heat storage heat exchanger 35, a heat storage tank 40, and a pump 41. When the liquid refrigerant of the air conditioner is cooled or overheated, the heat storage medium in the heat storage tank 40 is cooled or overheated. The heat storage medium is sent to the pipe 26 by the pump 41, and the control valve 2
After passing through 3, heat is exchanged with the liquid refrigerant of the air conditioner in the heat exchanger 21, and then returns to the heat storage tank through the pipe 25. Next, the means for cooling and heating the heat storage medium will be described. When cooling the heat storage medium, the four-way valve 31 is switched as shown by the solid line. The high-pressure gas refrigerant discharged from the compressor 30 passes through the four-way valve 31 to exchange heat with the outdoor air in the heat exchanger 32 and is condensed to become a liquid refrigerant. The liquid refrigerant is decompressed by the control valve 33 having a small opening, enters the heat storage heat exchanger 35, and exchanges heat with the heat storage medium. At this time, the heat storage medium is cooled, the refrigerant is evaporated to become a low-pressure gas refrigerant, and is sucked into the compressor 30 through the four-way valve 31. When the heat storage medium is overheated, the four-way valve 31 is switched as shown by the broken line. The high-pressure gas refrigerant discharged from the compressor 30 passes through the four-way valve 31, and the heat storage heat exchanger 35
And the heat storage medium is heat-exchanged. At this time, the heat storage medium is heated and the refrigerant is condensed to become a liquid refrigerant. The liquid refrigerant is decompressed by the control valve 33 having a small opening degree, enters the heat exchanger 32, exchanges heat with the outdoor air, becomes a low-pressure gas refrigerant, and is sucked into the compressor 30 through the four-way valve 31. According to the present embodiment, when the air conditioning load is less than or equal to the maximum capacity, the capacity of the compressor of the air conditioner can be reduced by the amount of improvement in the capacity of the air conditioner. The effect of peak power cut in summer can be obtained by performing it when the power plant is not operating.

The refrigerant of the cold heat source device 20 of the embodiment shown in FIGS. 4 and 5 may be the same as or different from the refrigerant of the air conditioner.

Next, another embodiment of the present invention is shown in FIG. In FIG. 6, the cooling and heating means for the heat storage medium is used by branching the refrigerant circuit of the air conditioner. That is, the gas pipe 9 and the liquid pipe 7 of the air conditioner are branched and connected to the gas pipe 9'and the liquid pipe 7'through the on-off valves 52 and 53, and the gas pipe 10 and the liquid pipe 8 of the air conditioner are also connected. It is branched and connected to the gas pipe 9'and the liquid pipe 7'through the on-off valves 54 and 55. The other end of the liquid pipe 7 ′ is connected to the heat storage heat exchanger 35 via the control valve 51.
The other end of the gas pipe 9'is connected to the other end of the heat storage heat exchanger 35. When the outdoor unit 1 is used to cool or heat the heat storage medium, the on-off valves 52 and 53 are opened and the on-off valves 54 and 55 are opened.
Keep closed. When cooling the heat storage medium, the outdoor unit 1 is brought into the cooling operation state, whereby the liquid refrigerant is sent to the control valve 51 through the liquid pipe 7, the on-off valve 53, and the liquid pipe 7 '. The opening degree of the control valve 51 is small, the liquid refrigerant is decompressed, enters the heat storage heat exchanger 35, and exchanges heat with the heat storage medium. At this time, the heat storage medium is cooled, and the refrigerant becomes a low-pressure gas refrigerant, and passes through the gas pipe 9 ′ and the opening / closing valve 52, and the gas pipe 9
Enter and return to outdoor unit 1. When heating the heat storage medium, the outdoor unit 2 is brought into the heating operation state, whereby the high-pressure gas refrigerant enters the heat storage heat exchanger 35 through the gas pipe 9, the on-off valve 52, and the gas pipe 9 ', and the heat storage medium is heated. Is heat exchanged with. At this time, the heat storage medium is heated, and the refrigerant condenses into a liquid refrigerant.
The liquid refrigerant passes through the control valve 51 whose opening is increased, and further,
It returns to the outdoor unit 1 through the liquid pipe 7 ′, the on-off valve 53, and the liquid pipe 7. When the outdoor unit 2 is used to cool or heat the heat storage medium, the on-off valves 52 and 53 are closed and the on-off valves 54 and 5 are closed.
5 may be opened and the same operation as the outdoor unit 1 may be performed.

[0019]

According to the present invention, the capacity can be increased by cooling or heating with the liquid refrigerant of the air conditioner and the cold heat source supplied from the cold heat source device. Further, since the cold heat source device is provided separately from the air conditioner, the capacity can be improved without being affected by the operating condition of the air conditioner.

When the cold heat source device is provided with a heat storage tank, the cold heat source device stores the cold heat, so that the cold heat can be stored even when the air conditioner is in operation, and the amount of cold heat stored is reduced, so that the capacity improving effect is lowered. Never. In addition, it is not necessary to install a heat storage tank for each indoor unit, so there is an effect of space saving.

Further, by utilizing the cold storage heat of the heat storage tank in the refrigerant circuit of the air conditioner, the refrigeration cycle in the cold heat source device can be omitted, which is cost effective.

[Brief description of drawings]

FIG. 1 is a system diagram of an air conditioner system showing an embodiment of the present invention.

FIG. 2 is a Mollier diagram showing the effect during cooling operation.

FIG. 3 is a Mollier diagram showing effects during heating operation.

FIG. 4 is a system diagram showing an embodiment of a cold heat source device.

FIG. 5 is a system diagram showing another embodiment of the cold heat source device.

FIG. 6 is a system diagram of an air conditioner system showing another embodiment of the present invention.

[Explanation of symbols]

1, 2 ... Outdoor unit, 3, 4, 5 ... Indoor unit, 7, 8 ... Liquid pipe,
11,30 ... Compressor, 14, 16, 23, 24, 33,
51 ... Control valve, 20 ... Cold heat source device, 21, 22 ... Heat exchanger, 35 ... Heat storage heat exchanger, 40 ... Heat storage tank, 41 ... Pump.

Claims (2)

[Claims] 1. A refrigeration cycle independent of an air conditioner in which an outdoor unit and a plurality of indoor units are combined is provided, and the refrigeration cycle is fed from a heat source side heat exchanger and an outdoor unit of the air conditioner to the indoor unit. A heat source device, comprising: a use-side heat exchanger for exchanging heat with the liquid refrigerant to be used. 2. A heat exchanger and a heat storage tank which are independent of the air conditioner, and the heat exchanger for exchanging heat between the liquid refrigerant of the air conditioner and an external heat source. A heat source device.