JP2000283585A - Heat storage air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize enhancement of energy saving by reduction of power consumption during cooling operation through a simple structure by arranging a refrigerant liquid pump and a supercooling liquid circuit for taking heat stored in a heat storage tank in parallel with a heat storage heat exchanger in a heat storage unit. SOLUTION: An outdoor unit 1 comprises a compressor 4, an outdoor heat exchanger 5, and an outdoor expansion valve 6 while a heat storage unit 2 comprises with a heat storage heat exchanger 7, heat storage tank 8, a heat storage expansion valve 10, and on/off valves 11a-11c and an indoor unit 3 comprises an indoor heat exchanger 12, and an indoor expansion valve 13. For a system comprising the units 1-3 coupled through refrigerant piping, a refrigerant liquid pump 15 and a supercooling liquid circuit 14 are provided in parallel with the heat storage heat exchanger 7 and the supercooling liquid circuit 14 is disposed along the inner or outer wall face of the heat storage tank 8. Liquefied refrigerant is fed from the heat storage unit 2 to the indoor unit 3 by means of a refrigerant liquid pump 15 and used for cooling indoor air through the indoor heat exchanger 12 before being returned back to the heat storage unit 2 while being vaporized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning operation utilizing heat storage using a refrigerant liquid pump and a refrigerant circuit for exchanging heat between water in a heat storage tank and refrigerant in the circuit (hereinafter referred to as "supercooling liquid circuit"). The present invention relates to a regenerative air conditioner that performs a cooling operation without operating a compressor, thereby realizing a reduction in power consumption.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional example of a regenerative air conditioner. In this conventional example, one outdoor unit 1 composed of a compressor 4, an outdoor heat exchanger 5, and an outdoor expansion valve 6, a heat storage heat exchanger 7, a heat storage tank 8, a heat storage expansion valve 10,
One heat storage unit 2 constituted by on-off valves 11a, 11b, 11c, indoor heat exchanger 12, indoor expansion valve 1
This is a system in which a single indoor unit 3 constituted by three indoor units 3 is connected by a refrigerant pipe.

Water 9 is stored in a heat storage tank 8. By operating the compressor 4 of the outdoor unit 1, a freezing operation is performed between the outdoor unit 1 and the heat storage unit 2. Heat can be stored in the water 9.

In order to utilize the heat of the heat storage tank 8 when performing the cooling operation of the indoor unit 3, the compressor 4 of the outdoor unit 1 is operated to circulate the refrigerant. At this time, the refrigerant is discharged from the compressor 4 of the outdoor unit 1, passes from the outdoor heat exchanger 5, passes through the heat storage heat exchanger 7 of the heat storage unit 2, and passes through the indoor unit 3
Is again sucked into the compressor 4 of the outdoor unit 1 via the indoor heat exchanger 12.

In the above prior art, the compressor 4 of the outdoor unit 1 had to be operated in order to use the heat stored in the heat storage tank 8 for the cooling operation of the indoor unit 3. In this case, the refrigerant is circulated to the outdoor unit 1 only where the refrigerant needs to be circulated only between the heat storage unit 2 and the indoor unit 3. Therefore, the refrigerant is circulated only between the heat storage unit 2 and the indoor unit 3. And the power consumption during the cooling operation was large.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 7-19539, a refrigerant liquid pump is provided in the heat storage unit, and the heat storage unit 2 and the indoor unit 3 can be connected to each other without using a compressor when performing a heat storage air conditioning operation. Cooling operation can now be performed in between.

[0007]

However, in the above-mentioned prior art which does not use a compressor, three types of circuits, ie, a heat transfer coil for ice making, a heat transfer coil for deicing, and a heat transfer coil for supercooling, are used. In addition, there is a problem that the structure is complicated, the pressure loss is large, and the pressure distribution must be considered.

Further, by using a supercooling heat transfer coil to prevent gas refrigerant from entering the refrigerant liquid pump inlet side, it is possible to prevent generation of abnormal noise due to cavitation generated in the refrigerant liquid pump and to prevent the refrigerant liquid pump from being compressed by gas. Although measures were taken to prevent a reduction in the service life, it was not sufficient. Further, there is a problem that it is not always easy to modify an existing heat storage tank and install a supercooling liquid circuit and a refrigerant liquid pump.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to improve energy saving by reducing power consumption during cooling operation using the heat storage amount of water in a heat storage tank. It is an object of the present invention to provide a regenerative air conditioner that can be easily implemented by using a supercooled liquid refrigerant, can easily realize stable cooling operation with a supercooled liquid refrigerant, and can further improve the reliability of a refrigerant liquid pump. .

[0010]

In order to achieve the above object, a regenerative air conditioner according to the present invention is characterized by what is described in each of the claims. The regenerative air conditioner according to the invention according to claim 1 as an item includes an outdoor unit including at least one or more units including a compressor, an expansion valve, and an outdoor heat exchanger, a refrigerant liquid pump, a heat storage tank, A heat storage unit composed of one or more units composed of an expansion valve and a heat storage heat exchanger and an indoor unit composed of one or more units composed of an expansion valve and an indoor heat exchanger are connected by refrigerant piping. In the heat storage type air conditioner, the refrigerant liquid pump and a supercooling liquid circuit that takes in the amount of heat stored in the heat storage tank are disposed in parallel with the heat storage heat exchanger in the heat storage unit. Especially It is an.

[0011]

In the regenerative air conditioner according to the first aspect of the present invention, the refrigerant liquid pump and the supercooling liquid circuit are disposed in parallel with the heat storage heat exchanger, and the amount of heat stored in the heat storage tank is reduced by the supercooling liquid. Heat is transferred to the circuit, and the refrigerant in the supercooled liquid circuit is liquefied. This liquid refrigerant is pumped to the indoor unit by the refrigerant liquid pump, and can be used for cooling operation of the indoor unit.

In the heat storage type air conditioner according to the second aspect of the present invention, the supercooling liquid circuit can be installed along the wall surface of the heat storage tank, and the supercooling liquid circuit can be fixed to the heat storage tank.

In the regenerative air conditioner according to the third aspect of the present invention, in order to improve the heat transfer of the amount of heat stored in the heat storage tank, a bypass for taking out water from the heat storage tank is provided at the bottom of the heat storage tank or the lower part of the side wall. It is provided between the upper side and the heat storage tank of the above-described embodiment. In addition to the above-described embodiment, water is taken out from the heat storage tank and heat exchange is performed. And
The bypass part for taking out the water of the heat storage tank is provided between the bottom part of the heat storage tank or the lower part of the side and the upper part of the side, so that the water in the heat storage tank and the water in the bypass part are circulated by natural convection due to the temperature change of the water. That's why.

In the regenerative air conditioner according to the fourth aspect of the present invention, the refrigerant liquid pump is provided in the heat storage tank, and the refrigerant liquid pump is used in a immersed state. Being always a liquid refrigerant, it is possible to prevent generation of abnormal noise due to cavitation generated in the refrigerant liquid pump when gas refrigerant is mixed into the inlet side, and to prevent shortening of life due to gas compression due to gas refrigerant mixing of the refrigerant liquid pump. As a result, the reliability of the refrigerant liquid pump is improved.

[0015]

1 to 4 show an embodiment of the present invention.
And the explanation is added below. FIG. 1 shows a system according to a first embodiment of the present invention.

In FIG. 1, one outdoor unit 1 composed of a compressor 4, an outdoor heat exchanger 5, and an outdoor expansion valve 6 is provided.
And one heat storage unit 2 including a heat storage heat exchanger 7, a heat storage tank 8, a heat storage expansion valve 10, and on-off valves 11a, 11b, 11c, an indoor heat exchanger 12, and an indoor expansion valve 13. For a system in which one indoor unit 3 is connected to a refrigerant pipe, a refrigerant liquid pump 15 and a supercooling liquid circuit 14 are provided in parallel with the heat storage heat exchanger 7. The heat storage tank 8 has a structure installed along the inner wall surface or the outer wall surface. Since the supercooling liquid circuit 14 has a structure capable of exchanging heat with the water 9 in the heat storage tank 8, when the water 9 in the heat storage tank 8 is storing heat, the refrigerant in the supercooling liquid circuit 14 is constantly cooled and liquefied.

The liquefied refrigerant is supplied to a refrigerant liquid pump 15
Is sent out from the heat storage unit 2 to the indoor unit 3, cools and evaporates the indoor air through the indoor heat exchanger 12, returns to the heat storage unit 2, is cooled again in the supercooling liquid circuit 14, and is cooled by the refrigerant liquid pump 15. Circulated in

FIG. 2 is a perspective view of a heat storage tank 8 according to a first embodiment of the present invention. This is an example in which a heat storage heat exchanger 7 is provided in a heat storage tank 8, and a supercooling liquid circuit 14 is installed along an inner wall surface or an outer wall surface of the heat storage tank 8. The structure is such that the supercooled liquid circuit 14 can be fixed by the heat storage tank 8 along the wall surface. Further, there is an advantage that the integral cooling or the supercooling liquid circuit 14 itself can be used as the wall of the heat storage tank 8.

FIG. 3 shows a second embodiment of the present invention, in which a bypass portion 16 of the heat storage tank 8 for exchanging heat with the supercooling liquid circuit 14 is provided between the bottom of the heat storage tank 8 or the lower side and the upper side. It is characterized by its structure.

The supercooling liquid circuit 14 of the first embodiment is
Although the heat transfer from the wall surface of the heat storage tank 8 is used, in the second embodiment, the water 9 in the heat storage tank 8 is taken out to the bypass unit 16 and used. By making the upper part of the side surface of the bypass part lower than the water surface of the water 9 stored in the heat storage tank 8, the extracted water passes upward from below by natural convection due to a temperature change.

Due to this convection effect, the water 9 in the heat storage tank 8 has an inexpensive structure utilizing natural circulation without using a power source such as a water pump. Applying a double pipe, a plate heat exchanger, or the like to the structure of the bypass section 16 for taking out the water 9 in the heat storage tank 8 is also an effective means for improving the heat exchange efficiency.
The second embodiment can be implemented in combination with the first embodiment.

FIG. 4 shows a system according to a third embodiment of the present invention. As compared with the first embodiment shown in FIG. 1, the refrigerant liquid pump 15 is immersed in the heat storage tank 8, so that the suction side of the refrigerant liquid pump 15 always becomes the liquid refrigerant, In the event of gas being mixed in the piping between the supercooling liquid circuit 14 and the refrigerant liquid pump 15 during the transition, the cavitation of the refrigerant liquid pump 15 and the generation of abnormal noise accompanying it, and the reduction of reliability due to overload, Can be prevented.

The third embodiment can be implemented in combination with the second embodiment.

[0024]

According to the present invention, it is possible to easily improve the energy saving property by a simple structure by reducing the power consumption during the cooling operation using the heat storage amount of the water in the heat storage tank. In addition, stable cooling operation using the supercooled liquid refrigerant can be easily realized. Further, the reliability of the refrigerant liquid pump can be further improved.

[Brief description of the drawings]

FIG. 1 is a schematic flow chart of a regenerative air conditioner according to a first embodiment.

FIG. 2 is a perspective view of a heat storage tank of the heat storage type air conditioner of the first embodiment.

FIG. 3 is a schematic flow chart of a regenerative air conditioner of a second embodiment.

FIG. 4 is a schematic flow chart of a regenerative air conditioner according to a third embodiment.

FIG. 5 is a schematic flow chart of a conventional regenerative air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outdoor unit, 2 ... Heat storage unit 3 ... Indoor unit, 4 ... Compressor 5 ... Outdoor heat exchanger, 6 ... Outdoor expansion valve 7 ... Heat storage heat exchanger, 8 ... Heat storage tank 9 ... Water, 10 ... Heat storage expansion valve 11a, 11b, 11c ··· On-off valve 12 · Indoor heat exchanger 13 · Indoor expansion valve · 14 · Supercooling liquid circuit 15 · Refrigerant liquid pump 16 · Bypass section

Continued on the front page (72) Inventor Kenji Togusa 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture F-term in Air Conditioning Systems Division, Hitachi, Ltd. (Reference) 3L092 TA12 UA03 UA34 VA07 WA15

Claims (4)

[Claims] 1. An outdoor unit comprising at least one or more compressors, expansion valves and an outdoor heat exchanger, and a refrigerant liquid pump, a heat storage tank, an expansion valve and a heat storage heat exchanger. A heat storage type air conditioner in which a heat storage unit composed of one or more units and an indoor unit composed of one or more units composed of an expansion valve and an indoor heat exchanger are connected by a refrigerant pipe; Wherein the refrigerant liquid pump and a supercooling liquid circuit for taking the amount of heat stored in the storage tank are arranged in parallel with the heat storage heat exchanger. 2. The regenerative air conditioner according to claim 1, wherein the supercooling liquid circuit is installed along an inner wall surface or an outer wall surface of the heat storage tank. 3. The supercooling liquid circuit according to claim 1, wherein the subcooling liquid circuit is provided in a bypass portion that connects a bottom portion of the heat storage tank or a lower portion of the side surface and an upper portion of the side surface provided in the heat storage tank. Thermal storage type air conditioner. 4. The regenerative air conditioner according to claim 1, wherein the refrigerant liquid pump is immersed in the heat storage tank.