JP3301342B2 - Thermal storage type air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative air conditioner that realizes a reduction in power consumption by daytime air conditioning by performing a heat storage operation and a heat storage air conditioning operation, and more particularly, to a refrigeration system for a heat storage air conditioner. Suitable for cycle and its control.

[0002]

2. Description of the Related Art For example, a compressor, a condenser, a flow control valve, and an evaporator are connected by a refrigerant pipe, a heat storage tank is provided in the middle of the refrigerant pipe, and a heat transfer tube is horizontally arranged in the heat storage tank. It is known as described in JP-A-6-101875.

[0003]

In the heat storage type air conditioner according to the prior art, when the capacity of the heat storage tank is increased, it is necessary to change the size in the horizontal direction in accordance with the increase of the heat transfer tubes. Therefore, there is a problem that the installation area must be increased when installing a large-sized heat storage tank.

When the heat transfer tubes are vertically stacked to reduce the installation area, the flow distribution of the refrigerant in the heat transfer tubes arranged near the water surface and the water bottom of the heat storage tank becomes uneven, and the heat storage tube inside the heat storage tank becomes uneven. There is a problem of uneven distribution of ice.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, to reduce the installation area of the heat storage tank even if the capacity is increased, to make the flow rate distribution of the refrigerant in the heat storage layer uniform, and to reduce the consumption during operation. An object of the present invention is to provide a regenerative air conditioner that reduces power consumption.

[0006]

In order to solve the above-mentioned problems, the present invention provides a compressor, a four-way switching valve, a first heat exchanger,
A first flow control valve, a first on-off valve, a second flow control valve,
The second heat exchanger is sequentially connected with a refrigerant pipe, and the heat transfer pipe is connected to the second heat exchanger.
Is contained in the heat storage tank, the first flow control valve and the first flow control valve.
From the compressor through a second on-off valve from between the
Or connected to a second flow control valve via a third on-off valve.
Heat storage type air conditioners,
A plurality of the heat transfer tubes arranged and vertically stacked,
A first expansion device connected to one end of the heat transfer tube;
A plurality of branch pipes connected to the first throttle device;
From the branch pipe to the first flow control valve and the first on-off valve;
And a third flow control valve connected between the
Of the second on-off valve and the third on-off valve
A collecting pipe connected therebetween, and the
The first expansion device connected to the heat transfer tube is connected to the lower heat transfer tube.
Pressure loss due to the difference in length.
The third flow rate control valve is set so that
Is the same as the amount of refrigerant flowing through each of the branch pipes.
It is controlled so that

[0007] Thus, the flow rate of the refrigerant flowing through the heat transfer tubes stacked in the heat storage tank can be controlled so as to be the same for each heat transfer tube, so that the flow rate distribution of the refrigerant in the heat storage layer can be made uniform. Therefore, uneven distribution of ice in the heat storage layer can be prevented, and power consumption can be reduced when the air conditioner is operated in the daytime using the heat storage tank.

[0008] In the above-mentioned apparatus , the collecting pipe is
A temperature sensor is connected to the refrigerant pipe between the second on-off valve and the third on-off valve.
A third flow rate according to the signal from the temperature sensor.
It is desirable to determine the opening of the regulating valve.

Thus, the flow rate of the refrigerant flowing through the heat transfer tubes stacked in the heat storage tank can be made the same for each heat transfer tube, so that the flow rate distribution of the refrigerant in the heat storage layer can be made uniform, Can prevent the uneven distribution of ice.

[0010]

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described in detail with reference to FIG. FIG. 1 is a block diagram of a regenerative air conditioner according to one embodiment, and FIG. 2 is a block diagram according to another embodiment. Reference numeral 1 denotes a compressor, in which a four-way switching valve 2, a first heat exchanger 3, a first flow control valve 4, a second flow control valve 5a, 5b, and a second heat exchanger 6a, 6b are sequentially connected to a refrigerant. Connected by piping. A first opening / closing valve 7 is disposed between the first flow rate regulating valve 4 and the gathering portion of the second flow rate regulating valves 5a and 5b.

Reference numeral 8 denotes a heat storage tank, which includes a plurality of heat transfer tubes 10a and 10a.
b, 10c, and 10d are stacked vertically in the heat storage tank 8 to form the heat storage heat exchanger 9. Each heat transfer tube 10a, 10b
And one of 10c and 10d is the first diaphragm device 17a, 1
7b and 17c, 17d, and a branch pipe 18
a and 18b, the third flow control valve 11a
And 11b.

The first expansion device 17a connected to the heat exchanger tube 10a installed above has a difference in length of the heat exchanger tube (10b−10) compared to the first expansion device 17b connected to the heat exchanger tube 10b.
The throttle amount is set so as to correspond to the pressure loss generated according to 10a).

The other ends of the third flow control valves 11a and 11b are connected between the first flow control valve 4 and the first on-off valve 7,
The first throttle device 17c connected to the heat transfer tube 10c installed above has a pressure generated by a difference in the length of the heat transfer tube (10d-10c) compared to the first throttle device 17d connected to the heat transfer tube 10d. The aperture is set so as to be equivalent to the loss.

The other one of the heat transfer tubes 10c and 10d is connected to the collecting pipe 19b and then connected via the second on-off valve 12 between the collecting portions of the second heat exchangers 6a and 6b and the four-way switching valve 2. Connected to. The respective collecting pipes 19a and 19b and the second
Temperature sensors 14a and 14b are arranged in the refrigerant pipe between the connection part of the on-off valve 12 and the third on-off valve 13,
The temperature sensors 14a and 14b, the arithmetic unit 15, the plurality of drive units 16a and 16b, and the third flow control valves 11a and 11b are connected by signal communication wires. Although not shown in the drawing, water is generally used as the heat storage medium in the heat storage tank 8, and the case of water will be described below. Of course, the heat storage medium is not limited to water.

Hereinafter, the flow of the refrigerant in the refrigeration cycle during the operation shown in FIG. 1 will be described. During the heat storage operation, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the first heat exchanger 3 via the four-way switching valve 2, and the liquefied refrigerant is reduced in the opening degree to reduce the flow rate and reduce the flow rate. The pressure is reduced by the third flow rate control valves 11a and 11b acting as the pressure control valves. Third flow control valve 11
Signals from the temperature sensors 14a and 14b are input to the arithmetic unit 15 to determine the opening degrees of the branch pipes 18a and 11b.
The opening degrees of the third flow control valves 11a and 11b are determined so that the amounts of the refrigerant flowing through the third flow control valves 11a and 11b are the same. The determined opening degree is transmitted to a plurality of driving devices 16a and 16b corresponding to the number of the third flow control valves 11a and 11b, and the third flow control valves 11a and 11b actually operate.

The refrigerant evaporating in the heat transfer tubes 10a, 10b, 10c and 10d of the heat storage heat exchanger 9 contained in the heat storage tank 8 cools the surrounding water and makes ice. At this time, the refrigerant flow rate is
The flow rate is adjusted by the first expansion devices 17a, 17b, 17c, 17d set so that the pressure loss is the same according to the respective lengths of 0a, 10b and 10c, 10d.

The evaporated refrigerant is supplied to the opened second on-off valve 1
2. Return to the compressor 1 via the four-way switching valve 2. At this time the first
On-off valve 7, third on-off valve 13, second flow control valve 5
The valves a and 5b are closed, and the refrigerant does not flow through the second heat exchangers 6a and 6b. Here, the driving devices 16a and 16b are arranged in accordance with the number of the third flow control valves 11a and 11b, but the driving device 1 is controlled by time division control of transmission data.
It is also possible to use one 6a, 16b.

In FIG. 1, each branch pipe 18
The heat transfer tubes 10a and 10b and the heat transfer tubes 10c and 10d connected to the a and 18b may be connected in a larger number. In this case, since the flow rate of the refrigerant may be uneven between the heat transfer tubes connected to the branch pipes 18a and 18b, the expansion devices corresponding to the differences in the lengths of the heat transfer tubes may be changed to the first expansion devices 17a and 17b. , 17c, 17d.

During the cooling operation using heat storage, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way switching valve 2 and the first heat exchanger 3.
And flows into the third flow control valves 11a and 11b from the first flow control valve 4 that has been opened to the maximum opening. The degree of opening of the third flow control valve 11 is determined by inputting a signal from the temperature sensor 14 to the arithmetic unit 15,
a and 18b are determined so that the amounts of refrigerant flowing therethrough are the same. The determined opening degree is the third flow control valve 11a, 11b
Are transmitted to the driving devices 16a and 16b corresponding to the above, and the third flow control valves 11a and 11b actually operate. The refrigerant flows through the third flow control valves 11a, 11b, and flows through the branch pipes 18a,
The respective heat transfer tubes 10a, 10b, 10
c, flow into 10d and melt the surrounding ice while exchanging heat. At this time, the flow rate of the refrigerant is controlled by the heat transfer tubes 10a, 10b and 10
The first throttle devices 17a, 17b, 1 are set so that the pressure loss is the same according to the respective lengths of c, 10d.
It is also adjusted by 7c and 17d.

The refrigerant supercooled by heat exchange acts as a pressure reducing mechanism via the third opening / closing valve 13 which is opened.
The pressure is reduced by the flow control valves 5a and 5b of the second heat exchanger 6
The air in the room is cooled by being evaporated at a and 6b. The evaporated refrigerant passes through the four-way switching valve 2 and is supplied to the compressor 1
Return to At this time, the first on-off valve 7 and the second on-off valve 12 are closed, and no refrigerant flows from the heat transfer tubes 10a, 10b, 10c, and 10d to the compressor 1 via the four-way switching valve 2.

The third flow control valves 11a and 11b are controlled by the drive unit 16 to open to the maximum opening degree. However, there is a structural problem such as a valve diameter, and the pressure loss may increase. In this case, it is preferable to arrange a refrigerant pipe so as to bypass the upstream and downstream sides of the third flow control valves 11a and 11b, and add an on-off valve in the middle.

The opening degree of the third flow control valves 11a and 11b is determined by inputting a signal from the temperature sensor 14 to the arithmetic unit 15,
The amounts of the refrigerant flowing through the respective branch pipes 18a and 18b are determined so as to be the same. The determined opening degree corresponds to the number of the driving devices 16a corresponding to the number of the third flow control valves 11a and 11b,
The signal is transmitted to 16b, and the third flow control valve 11 operates. Here, the driving devices 16a and 16b are connected to the third flow control valve 11
Although they are arranged in accordance with the number of devices a and 11b, one device may be provided by time-divisionally controlling transmission data.

Next, during normal cooling without using heat storage, high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way switching valve 2 and the first
Condensed in the heat exchanger 3 of FIG.
The pressure is reduced by the second flow control valves 5a and 5b acting as a pressure reducing mechanism via the flow control valve 4 and the first opening / closing valve 7 which opens, and evaporated by the second heat exchangers 6a and 6b. Cool indoor air. The evaporated refrigerant returns to the compressor 1 via the four-way switching valve 2. At this time, the third flow control valve 1
1a, 11b and the third on-off valve 13 are closed, and no refrigerant flows through the heat transfer tubes 10a, 10b, 10c, 10d.

Further, during the heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the second heat exchangers 6a and 6b via the four-way switching valve 2 switched in the flow direction. The room air is heated. Second flow control valves 5a, 5b opened to maximum opening, first open / close valve 7 opened
The refrigerant that has been depressurized by the first flow control valve 4 acting as a decompression mechanism via the first heat exchanger 3 and evaporated by the first heat exchanger 3 returns to the compressor 1 via the four-way switching valve 2. At this time, the third flow control valves 11a, 11b, the second on-off valve 12, and the third on-off valve 13 are closed and the heat transfer tubes 10a, 10b, 10c, 1
No refrigerant flows in 0d.

As described above, the third flow control valves 11a, 1
The temperature sensor 14a, 14b, the arithmetic unit 1
5. The flow rate of the refrigerant flowing through the heat transfer tubes 10a, 10b, 10c, and 10d can be adjusted by individually controlling the driving devices 16a and 16b.

Next, another embodiment of the regenerative air conditioner of the present invention will be described with reference to FIG. 1 is a compressor,
Four-way switching valve 2, first heat exchanger 3, first flow control valve 4, second flow control valve 5a, 5b, second heat exchanger 6
a, 6b, the four-way switching valve 2, and the compressor 1 are sequentially connected by a refrigerant pipe. First flow control valve 4 and second flow control valve 5
The first on-off valve 7 is arranged between a and 5b. One of the plurality of heat transfer tubes 10a, 10b is connected to the first expansion devices 17a, 17
b, and then to the branch pipe 18a, and then to the third flow control valve 11a. Similarly, heat transfer tubes 10c, 10
d is connected to the first expansion devices 17c and 17d, and further connected to the branch pipe 18b.
b. The other ends of the third flow control valves 11a and 11b are connected between the first flow control valve 4 and the first on-off valve 7.

The first expansion device 17a connected to the heat transfer tube 10a installed above the heat storage heat exchanger 9 included in the heat storage tank 8 is the first expansion device 17b connected to the heat transfer tube 10b. Is set such that the throttle amount corresponds to the pressure loss generated by the difference in the length of the heat transfer tubes (10b-10a). Similarly, one of the heat transfer tubes 10c and 10d is
Connected to the squeezing devices 17c and 17d and a branch pipe 18b
After that, it is connected to the third flow control valve 11b.
The other ends of the third flow control valves 11a and 11b are connected between the first flow control valve 4 and the first on-off valve 7. Similarly, a first expansion device 1 connected to a heat transfer tube 10c installed above.
7c is a first expansion device 17 connected to the heat transfer tube 10d.
The throttle amount is set so as to be equal to the pressure loss generated due to the difference (10d-10c) in the length of the heat transfer tubes compared to d.

First flow control valve 4 and third flow control valve 1
1a is connected to one of the fourth on-off valves 20a. The other end of the fourth on-off valve 20a is connected to the second throttle device 21a, and is connected between the third flow control valve 11a and the branch pipe 18a. Similarly, a pipe branched from between the first flow control valve 4 and the third flow control valve 11b is connected to one of the fourth on-off valves 20b. The other end of the fourth on-off valve 20b is connected to the second throttle device 21b, and is connected between the third flow control valve 11b and the branch pipe 18b. The second expansion devices 21a and 21b are used to reduce the amount of pressure so as to have a pressure loss corresponding to the difference in the length of the heat transfer tubes caused by the difference between the installation height of the heat transfer tubes 10a and 10b and the installation height of the heat transfer tubes 10c and 10d. Is set to

The other one of the heat transfer tubes 10a and 10b is connected to the collecting pipe 19, and then, through the second on-off valve 12, between the collecting part of the second heat exchangers 6a and 6b and the four-way switching valve 2. Connecting. Similarly, the other one of the heat transfer tubes 10 c and 10 d is connected to the collecting tube 19. The refrigeration cycle is connected between the collecting pipe 19 and the second on-off valve 12 and between the first on-off valve 7 and the collecting part of the second flow control valves 5a and 5b via the third on-off valve 13. Is configured. Each collecting pipe 19,
A temperature sensor 14 is disposed in the refrigerant pipe between the connection portion of the second on-off valve 12 and the third on-off valve 13, and the temperature sensor 14, the arithmetic unit 15, and the drive unit 1 are connected by signal communication wiring.
6. The third flow control valves 11a and 11b are connected.

Next, the flow of the refrigerant in the refrigeration cycle shown in FIG. 2 will be described. During the heat storage operation, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the first heat exchanger 3 via the four-way switching valve 2, and the liquefied refrigerant is reduced in the opening degree to reduce the flow rate and reduce the flow rate. Third flow control valves 11a, 1
Reduce the pressure in 1b. A signal from the temperature sensor 14 is input to the arithmetic unit 15 and the opening of the third flow control valves 11a and 11b is adjusted so that the total amount of refrigerant becomes a predetermined flow rate. The degree is determined. The determined opening degree is transmitted to the driving device 16 and the third flow control valve 11
a and 11b operate. Heat transfer tubes 10a, 10b, 10
The refrigerant evaporating at c and 10d cools the surrounding water to make ice. At this time, the flow rate of the refrigerant is the first expansion device 17a, 17b,
The flow rate is adjusted by 17c and 17d. The evaporated refrigerant returns to the compressor 1 via the opened second on-off valve 12 and the four-way switching valve 2. At this time, the first on-off valve 7 and the third on-off valve 1
3. The second flow control valves 5a and 5b are closed, and no refrigerant flows through the second heat exchangers 6a and 6b.

During the cooling operation using the heat storage, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way switching valve 2 and the first heat exchanger 3.
From the fourth on-off valves 20a, 20b that have been condensed and opened through the second throttle devices 21a, 21b to the branch pipes 18a, 1b.
8b, first aperture devices 17a, 17b, 17c, 17d
Flows into the heat transfer tubes 10a, 10b, 10c, and 10d to melt ice while exchanging heat. The third flow control valve 11
Since a and 11b are fully closed, the refrigerant does not flow. The refrigerant supercooled by the heat exchange passes through the opened third opening / closing valve 13 to act as a pressure reducing mechanism in the second flow control valve 5a,
The pressure is reduced in 5b, and the indoor air is cooled by evaporating in the second heat exchangers 6a and 6b. The evaporated refrigerant returns to the compressor 1 via the four-way switching valve 2. The first on-off valve 7 and the second on-off valve 12 are closed, and the heat transfer tubes 10a, 1
No refrigerant flows from 0b, 10c, and 10d to the compressor 1 via the four-way switching valve 2.

Next, during normal cooling without using heat storage, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way switching valve 2 and the first
Condensed in the heat exchanger 3 of FIG.
The pressure is reduced by the second flow control valves 5a and 5b acting as a pressure reducing mechanism via the flow control valve 4 and the first opening / closing valve 7 which opens, and is evaporated by the second heat exchangers 6a and 6b. The indoor air is cooled. The evaporated refrigerant is a four-way switching valve 2
And returns to the compressor 1 via. A third flow control valve 11a,
11b, third on-off valve 13, fourth on-off valve 20a, 20
b is closed and the heat transfer tubes 10a, 10b, 10c, 10
No refrigerant flows in d.

During the heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the second heat exchangers 6a and 6b via the four-way switching valve 2 whose flow direction is switched, thereby indoors. The air is heated. The pressure is reduced by the first flow control valve 4 acting as a pressure reducing mechanism via the second flow control valves 5a and 5b opened to the maximum opening and the first opening / closing valve 7 which opens, and the first heat exchange is performed. The refrigerant evaporated in the compressor 3 returns to the compressor 1 via the four-way switching valve 2. Third flow control valve 11a, 1
1b, the second on-off valve 12, the third on-off valve 13, and the fourth on-off valves 20a and 20b are closed and the heat transfer tubes 10a and 10b are closed.
No refrigerant flows through b, 10c, and 10d.

As described above, the temperature sensor 14 and the arithmetic unit 1
5. The third flow control valves 11a, 11
b at the same time, the first throttle devices 17a, 17
The flow distribution can be made uniform by b. By simultaneously opening and closing the fourth on-off valves 20a and 20b during the cooling operation using heat storage, the flow rate of the second expansion devices 18a and 18b can be controlled, so that the flow rate of the refrigerant can be made uniform. Further, since the configuration includes the second aperture devices 21a and 21b,
Even when the flow control valves 11a and 11b are insufficiently opened, it is possible to prevent the refrigerant flow from becoming uneven.

[0036]

As described above, according to the present invention,
A plurality of heat transfer tubes are vertically stacked, and the third flow control valve connected to the heat transfer tubes and the opening of the flow control valve are controlled, so that the flow rate of the refrigerant flowing through the heat transfer tubes stacked in the heat storage tank Can be controlled to be the same for each heat transfer tube, so that the flow rate distribution of the refrigerant in the heat storage layer can be made uniform. Therefore, it is possible to obtain a heat storage type air conditioner in which the installation area of the heat storage tank is reduced and power consumption during operation is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a refrigeration cycle according to one embodiment of the present invention.

FIG. 2 is a block diagram of a refrigeration cycle according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2 ... 4-way switching valve, 3 ... First heat exchanger, 4
... first flow control valves, 5a, 5b ... second flow control valves,
6a, 6b: second heat exchanger, 7: first on-off valve, 8 ...
Heat storage tank, 9 ... heat storage heat exchangers, 10a, 10b, 10c,
10d: heat transfer tube, 11a, 11b: third flow control valve,
12: second on-off valve, 13: third on-off valve, 14, 14
a, 14b: temperature sensor, 15: arithmetic device (opening control means), 16, 16a, 16b: drive device, 17a, 17
b, 17c, 17d: first diaphragm device, 18a, 18b
... branch pipes, 19, 19a, 19b ... collecting pipes, 20a, 2
0b: Fourth on-off valve, 21a, 21b: Second throttle device.

Continuation of the front page (72) Inventor Fumihiko Sugiyama 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Within Hitachi Shimizu Engineering Co., Ltd. (56) References JP-A-5-346249 (JP, A) JP-A-4-320795 (JP) , A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F28D 20/00 F24F 5/00 102 F25B 13/00 351 F25B 1/00 321

Claims (2)

(57) [Claims] 1. A refrigerant, a four-way switching valve, a first heat exchanger, a first flow control valve, a first opening / closing valve, a second flow control valve, and a second heat exchanger are sequentially connected to a refrigerant. A heat storage tank connected by piping and containing a heat transfer tube is configured to connect the compressor or the third on-off valve via a second on-off valve from between the first flow control valve and the first on-off valve. A heat storage type air conditioner connected to a second flow control valve via the heat transfer tube, wherein the heat transfer tubes are arranged in a heat storage tank in a horizontal direction and stacked in a plurality of vertical directions, and are connected to one end of the heat transfer tubes. A first throttle device, a plurality of branch pipes connected to the plurality of first throttle devices, and a plurality of branch pipes connected from the branch pipe to the first flow control valve and the first on-off valve. A third flow control valve, connected to the other end of the heat transfer tube, connected between the second on-off valve and the third on-off valve Wherein the first throttle device connected to the heat transfer tube installed above has a throttle amount corresponding to a pressure loss generated due to a difference in length between the first throttle device and the lower heat transfer tube. And the opening of the third flow control valve is controlled such that the amount of refrigerant flowing through each of the branch pipes is the same. 2. A temperature sensor according to claim 1, wherein a temperature sensor is provided from the collecting pipe to a refrigerant pipe between the second on-off valve and the third on-off valve. A regenerative air conditioner characterized in that an opening of the third flow control valve is determined by a signal.