JP2001082772A - Thermal storage unit and operating method for air conditioner incorporating it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the quantity of a refrigerant by opening first and second on/off valves at the time of cold storage operation and closing any one of them at the time of utilization cooling operation thereby halving the size of a supercooler and enhancing the thermal storage capacity. SOLUTION: A thermal storage heat exchanger 1 has two sets of path group, i.e., a first path group coupled with a first distributor and a second path group coupled with a second distributor. The first and second path groups are also coupled with a first and second headers, respectively. At the time of cold storage operation, first and second on/off valves 27, 28 are closed, first and second path on/off valves 10-13 are opened and a third on/off valve 29 is opened to supply refrigerant entirely to the thermal storage heat exchanger 1. At the time of utilization cooling operation, first and third on/off valves 27, 29 are closed, any ones of the first path on/off valves 10, 12 or the second path on/off valves 11, 13 are closed, and the second on/off valve 28 is opened to supply refrigerant only to one half of the thermal storage heat exchanger 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat storage unit for performing ice making at night in order to reduce power consumption during daytime air conditioning operation, and to a method of operating an air conditioner incorporating the heat storage unit.

[0002]

2. Description of the Related Art Conventionally, a heat storage heat exchanger of a heat storage unit increases the heat transfer area by increasing the diameter of a heat transfer tube or increasing the length of the heat transfer tube, thereby improving the performance of the heat exchanger. I raised it. As a conventional technique relating to such a heat storage heat exchanger, there is a technique disclosed in Japanese Patent Application Laid-Open No. 10-267575.

[0003]

However, considering only the improvement of the heat storage performance of the heat storage heat exchanger as in the above-mentioned prior art, it is necessary to increase the pipe length or the pipe diameter to increase the heat transfer area. The internal volume of the heat exchanger increases, and the required amount of charged refrigerant in the refrigeration cycle increases. Also, when the heat storage heat exchanger is used as a refrigerant subcooler during the cooling operation, the refrigerant exists exclusively as a liquid in the heat storage heat exchanger. The greater the internal volume of the vessel, the greater the difference in the required amount of refrigerant between the two operation modes during the use cooling operation and during the cold storage operation.

[0004] Therefore, if the amount of refrigerant in the refrigeration cycle is determined in accordance with the required amount of refrigerant during the cold storage operation, the refrigerant will run short during the use cooling operation. Conversely, if the amount of refrigerant is determined in accordance with the required amount of refrigerant during the use cooling operation, in this case, there is a problem that excess refrigerant is generated during the cool storage operation.

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat storage unit and a heat storage unit capable of improving the heat storage capacity, reducing the difference in the required amount of refrigerant between a cold storage operation and a use cooling operation, and reducing the amount of charged refrigerant. It is an object of the present invention to provide a method of operating an air conditioner incorporating the above.

[0006]

Means for Solving the Problems To achieve the above object, an air conditioner and an operation method thereof according to the present invention are characterized by what is described in the claims. In particular, the air conditioner according to the invention according to claim 1 as an independent claim includes an outdoor unit including a compressor, a four-way valve, an outdoor heat exchanger, and an outdoor flow control valve, and an indoor heat exchanger and an indoor flow control valve. In a heat storage unit including a heat storage heat exchanger, a heat storage tank, and a heat storage flow rate control valve that are incorporated in an air conditioner including an indoor unit configured, the heat storage unit includes a heat transfer passage of the heat storage heat exchanger. Into at least two sets of path groups, one end of the first path group is connected to the first distributor, the other end is connected to the first header, and one end of the second path group is connected to the second distributor, other Are connected to a second header, the pipes connected to the first and second distributors are joined by a first junction pipe, and the pipes connected to the first and second headers are connected to a second header. The first and second pipes are connected to each other by connecting pipes.
At least one first and second path open / close valve is provided for each of the path groups, and the first junction pipe is connected to the outdoor flow control valve of the outdoor unit and the indoor unit of the indoor unit via the heat storage flow control valve. A first on-off valve connected to a flow control valve is connected to the outdoor flow control valve side of a first on-off valve, and the second merging pipe branches off, and one of the branches is connected via a second on-off valve. The first open / close valve is connected to the indoor flow control valve side, and the other end is connected to a pipe connecting the indoor heat exchanger of the indoor unit and the four-way valve of the outdoor unit via a third open / close valve. This is characterized in that the configuration is such that:

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows a part of a heat storage unit 14 incorporated in an air conditioner of the present invention. Of the two sets of paths coming out of one of the heat storage heat exchangers 1, all the first path groups 2 are connected to the first distributor 4, and similarly all the second path groups 3 are connected to the second distributor 5. Connect to These are the first pass on-off valves 1 respectively.
It merges with the first merging pipe via the zero and second path on-off valves 11.

Further, of the two sets of paths coming out of the other part of the heat storage heat exchanger 1, all the first paths 6 are connected to the first header 8, and similarly all the second paths 7 are connected. Connect to the second header 9. These are the first pass on-off valves 1 respectively.
It merges into the second junction pipe via the second and second path on-off valves 13.

Therefore, the first path on-off valves 10 and 12 are on the same path, and the second path on-off valves 11 and 13 are also on the same path. In FIG. 1, the number of heat storage heat exchangers 1 is four, but the number is arbitrary, and the on-off valve is either one of the first-pass on-off valve 10 or the first-pass on-off valve 12, and
Only one of the second path on-off valve 11 and the second path on-off valve 13 may be provided. The number of passes may be two or more.

FIG. 2 is a diagram showing a flow of an air conditioner using the heat storage unit 14. The discharge pipe coming out of the compressor 20 is connected to an outdoor heat exchanger 22 through a four-way valve 21.
, The outdoor flow control valve 23, the first on-off valve 27,
The indoor flow control valve 24 and the indoor heat exchanger 25 are connected in this order, and are connected to the suction pipe of the compressor 20 via the four-way valve 21.

The outdoor unit 15 comprises the compressor 20, the four-way valve 21, the outdoor heat exchanger 22, and the outdoor flow control valve 23. Further, the indoor unit 16 is constituted by the indoor heat exchanger 25 and the indoor flow control valve 24.

In the heat storage unit 14, a pipe branched from between the outdoor flow control valve 23 and the first opening / closing valve 27 is connected to a first junction pipe via the heat storage flow control valve 26, and the first junction pipe is connected to the first junction pipe. Is branched into two, respectively connected to the first pass on-off valve 10 and the second pass on-off valve 11, and connected to one of two sets of pipes coming out of the heat storage heat exchanger 1. The other two sets of pipes exiting from the heat storage heat exchanger 1 join the second junction pipe via the first path on-off valve 12 and the second path on-off valve 13, and further connect the second on-off valve 28. It is connected to a pipe branched from between the first opening / closing valve 27 and the indoor flow control valve 24 via the first opening / closing valve 27.

A pipe branched from between the second merging pipe where the first-pass on-off valve 12 and the second-pass on-off valve 13 join and the second on-off valve 28 passes through a third on-off valve 29. Thus, the cycle is connected to a pipe branched from between the indoor heat exchanger 25 and the four-way valve 21.

Using this cycle, the indoor heat exchanger 2
5, the first on-off valve 27 and the second on-off valve 28 are closed, the first and second pass on-off valves 10, 11, 12 and 13 are opened, and the third on-off valve 29 is opened. Is opened, the refrigerant flows through the entire heat storage heat exchanger 1.
On the other hand, at the time of the use cooling operation using the indoor heat exchanger 25, the first on-off valve 27 and the third on-off valve 29 are closed, and the first-pass on-off valves 10 and 12 or the second-pass on-off valve 11 are closed.
And 13 are closed, and the second on-off valve 2
Opening 8 allows the refrigerant to flow through only half of the heat storage heat exchanger 1.

Similarly, during the use heating operation, the first on-off valve 27 and the third on-off valve 29 are closed, and the first path and the second
By opening the path opening / closing valves 10, 11, 12, and 13, and further opening the second opening / closing valve 28, the refrigerant flows through the entire heat storage heat exchanger 1. On the other hand, during the heat storage operation, the third on-off valve 29 is opened, and either the first path on-off valves 10 and 12 or the second path on-off valves 11 and 13 are closed. By closing the second on-off valve 28, the refrigerant can flow through only half of the heat storage heat exchanger 1. However, FIG. 2 shows only one example of the heat storage type air conditioner, and the heat storage unit 14 of the present invention can be applied to other types of heat storage type air conditioners.

FIG. 3 is a view showing one embodiment of the heat storage heat exchanger 1 used in the heat storage unit 14 of FIG. In this heat storage heat exchanger 1, two identically shaped metal plates 30 are overlapped, the periphery thereof is welded, and the inside of the periphery of the metal plate 30 is air-tightly adjacent to each other as a flow path for a refrigerant. Welding is performed to form two passes 31. Then, the pipes 32 are connected to the upper portions of the metal plates 30 so as to match the paths 31. By manufacturing in this way, the path 31 in which adjacent flow paths are secured
The structure is such that the refrigerant does not flow between each other. Although the path 31 is formed in the longitudinal direction in FIG. 3, the path 31 may be formed in the short direction, and the number of paths may be plural.

FIGS. 4 and 5 show another embodiment of the heat storage heat exchanger 1 using a conventional coiled tube used in the heat storage unit 14 of FIG. 1, similarly to FIG. The heat storage heat exchanger 1 has a configuration as shown by A so that ices 41 formed around two heat transfer tubes 40 of the same set in parallel during ice making can be connected to each other.

That is, using the radius B of ice, the interval A of the same set of heat transfer tubes is represented by A <B + B, while the other portion of one heat transfer tube or the other set of heat transfer tubes 40 is C. The configuration is such that C> B + B using the intervals that are not connected to each other as shown. As described above, it is preferable that the heat transfer tubes 40 of the same set are spaced apart to a certain extent in order to gain a heat transfer area during ice making, but they may be in contact with each other and further welded. Further, in FIG. 4, the arrangement direction of the pipes connecting the ice to each other is the vertical direction, but may be the horizontal direction or the oblique direction, and the number of passes may be plural as shown in FIG.

[0020]

According to the present invention, in the cold storage operation and the use cooling operation, when performing the cold storage operation, the first pass and the second pass on-off valves are all opened and the area of the evaporator is enlarged, so that the cold storage can be efficiently performed. When using cooling operation, the amount of liquid refrigerant that accumulates in the subcooler by closing one set of the first pass on-off valve or the second pass on-off valve and halving the size of the subcooler Can be reduced. Thus, by reducing the required amount of refrigerant during the use cooling operation, the amount of refrigerant charged in the air conditioner can be reduced.

Further, since the heat storage heat exchanger of the present invention makes ice in a shape close to a plate, high IPF can be achieved.
On the other hand, even in a conventional heat storage heat exchanger using a flexible tube, even if one of the on-off valves is closed, the ice is sufficiently removed by the other heat transfer tube by the same set of two heat transfer tubes that are in contact with or adjacent to each other. Can be used.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a heat storage unit of the present invention.

FIG. 2 is a flow sheet of an air conditioner using the heat storage unit of the present invention.

FIG. 3 is a front view of one embodiment of a heat storage heat exchanger used in the heat storage unit of the present invention.

FIG. 4 is a view of another embodiment of the heat storage heat exchanger used in the heat storage unit of the present invention.

FIG. 5 is a diagram showing an arrangement of another embodiment of the heat storage heat exchanger used in the heat storage unit of the present invention. (a) Plan view. (B) Front view as viewed from aa arrow. (C) The side view seen from the arrow bb.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heat storage heat exchanger 2, 6 ... 1st path group 3, 7 ... 2nd path group 4 ... 1st distributor 5 ... 2nd distributor 8 ... 1st header 9 ... 2nd header 10 ... 1st pass on-off valve 11 ... 2nd pass on-off valve 12 ... 1st pass on-off valve 13 ... 2nd pass on-off valve 14 ... heat storage unit 15 ... outdoor unit 16 ... indoor unit 20 ... compressor 21 ... four-way valve 22 ... outdoor heat Exchanger 23 ... Outdoor flow control valve 24 ... Indoor flow control valve 25 ... Indoor heat exchanger 26 ... Heat storage flow control valve 27 ... First on-off valve 28 ... Second on-off valve 29 ... Third on-off valve 30 ... Metal Plate 31 ... Pass 32 ... Piping 40 ... Heat transfer tube 41 ... Ice

Claims (5)

[Claims] 1. An air conditioner including an outdoor unit including a compressor, a four-way valve, an outdoor heat exchanger, and an outdoor flow control valve, and an indoor unit including an indoor heat exchanger and an indoor flow control valve. A heat storage unit including a heat storage heat exchanger, a heat storage tank, and a heat storage flow rate adjustment valve, wherein the heat storage unit divides a heat transfer passage of the heat storage heat exchanger into at least two sets of path groups; One end of the path group is connected to the first distributor, the other end is connected to the first header, one end of the second path group is connected to the second distributor, and the other end is connected to the second header, First and second
The pipes connected to the distributors are merged by a first merging pipe, and the pipes respectively connected to the first and second headers are merged by a second merging pipe. At least one first and second path opening / closing valve is provided for each of the first and second path groups, and the first merging pipe is connected to an outdoor flow control valve of the outdoor unit via a heat storage flow control valve. The first on-off valve is connected to the outdoor flow control valve side of the first on-off valve in the middle of the pipe connecting the indoor flow control valve of the indoor unit, and the second merging pipe is branched, and one of the two is connected to the second flow control pipe. An indoor heat exchanger of the indoor unit and a four-way valve of the outdoor unit are connected to the first on-off valve via the on-off valve and connected to the indoor flow rate regulating valve side of the first on-off valve via a third on-off valve. Configuration to connect to piping to connect Thermal storage unit, characterized in that the. 2. The heat storage heat exchanger according to claim 1, wherein two metal plates of the same shape are stacked in parallel at a predetermined interval, and the periphery thereof is welded. A plurality of sets of heat storage heat exchangers are welded to form a plurality of paths that are airtight and adjacent to each other as paths, and a plurality of sets of the heat storage heat exchangers are disposed in the heat storage tank. Item 2. The heat storage unit according to Item 1. 3. The heat storage heat exchanger is formed by contacting or welding a plurality of parallel heat transfer tubes with each other, or by a pipe spacing at which ice formed around the plurality of parallel heat transfer tubes during ice making can be connected to each other. The heat storage unit according to claim 1, wherein the heat storage unit is configured as a set, and a plurality of sets of the heat storage heat exchangers are disposed in the heat storage tank. 4. A method for operating an air conditioner incorporating the heat storage unit according to claim 1, wherein the first and second on-off valves are closed during a cold storage operation. 3, the first and second path on-off valves connected before and after the heat storage heat exchanger are opened, and during the use cooling operation, the first and third on-off valves are closed. 2. The air conditioner according to claim 1, wherein one of the first path on-off valve and the second path on-off valve is opened and the other path on-off valve is closed. Driving method. 5. An operation method of an air conditioner incorporating the heat storage unit according to claim 1, wherein the first and third on-off valves are closed during a heating operation.
Opening the second on-off valve, opening the first and second pass on-off valves connected before and after the heat storage heat exchanger, closing the first and second on-off valves during heat storage operation, An air conditioner characterized by opening a third on-off valve, opening one of the first path on-off valve and the second path on-off valve, and closing the other path on-off valve. How to operate the device.