JP2001304782A - Heat-storing device and heat storage type air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-storing device for showing a larger heat storage capacity than before using a heat storage coil whose heat transfer area is equal to conventional one. SOLUTION: A heat-storing device A consists of a refrigerant circuit 21 where a compressor 1, a heat source side heat exchanger 2, a beam limiting device 3, and a heat storage coil 10a are successively connected, and a heat storage bath 9 for accommodating the heat storage coil 10a and a heat storage refrigerant 8. In the heat storage coil 10a, the sectional area of a pipe at the refrigerant inlet side at the time of heat storage operation for cooling the heat storage refrigerant 8 is smaller than that at other parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat storage device and a heat storage type air conditioner.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a heat storage coil housed in a heat storage tank in a conventional heat storage type air conditioner. As can be seen from this figure, the conventional heat storage coil 10 has the same structure from one end to the other end. In other words, the heat transfer coil 10 has the advantage that the heat storage coil 10 is easy to process because the tube material, the tube inner diameter, and the tube cross-sectional area are configured to be constant over the entire length.

[0003]

However, the prior art has the following problems. That is, a heat storage operation for cooling using the conventional heat storage coil 10 (operation in which a low-temperature refrigerant is circulated in the heat storage coil, and heat exchange with the refrigerant cools the heat storage medium in the heat storage tank to store cold heat. In the case of performing the following, the heat transfer coefficient in the pipe became small and the heat exchange rate between the heat storage medium and the refrigerant also became small because the dryness of the refrigerant near the refrigerant inlet of the heat storage coil 10 was small. Therefore, there is a problem that the heat transfer area of the heat storage coil 10 cannot be effectively used, and a sufficient heat exchange capacity (heat storage capacity) cannot be exhibited.

On the other hand, the heat storage cooling operation in which the heat storage coil 10 functions as a condenser (cooling and condensing the refrigerant in the heat storage coil by the cold stored in the heat storage medium, and flowing this refrigerant to the use side heat exchanger) , The operation of cooling the interior of the room:
In the vicinity of the refrigerant outlet, the degree of dryness of the refrigerant is reduced, so that the heat transfer coefficient in the pipe is reduced, and the heat exchange rate between the heat storage medium and the refrigerant is also reduced. Therefore, there is a problem that the heat transfer area of the heat storage coil 10 cannot be effectively used, a sufficient heat exchange ability (condensing ability) cannot be exhibited, and a cooling ability also decreases. In addition, since the internal volume of the heat storage coil 10 is large,
There is also a problem that the amount of refrigerant charged in the refrigerant circuit increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has a heat storage device that uses a heat storage coil having a heat transfer area equivalent to that of the related art to exhibit a larger heat storage capacity than the related art. It is an object of the present invention to provide a heat storage type air conditioner that uses a heat storage coil having a heat area equivalent to that of the related art and exhibits a greater cooling capacity than before.

[0006]

In order to achieve the above object, a heat storage device according to a first aspect of the present invention comprises a refrigerant circuit in which a compressor, a heat source-side heat exchanger, a throttle device, and a heat storage coil are sequentially connected. And a heat storage device comprising a heat storage coil and a heat storage tank for storing the heat storage medium, wherein the heat storage coil has a smaller pipe cross-sectional area on the refrigerant inlet side during the heat storage operation for cooling the heat storage medium than the other sections. Is what it is.

According to a second aspect of the present invention, in the first aspect, the heat storage coil has a structure in which the heat storage coil is branched into a plurality of branch pipes at a branch portion located in the middle thereof, and is provided on the refrigerant inlet side during the heat storage operation. The pipe cross-sectional area of the non-branched portion is smaller than the total cross-sectional area of the branch pipe disposed on the refrigerant outlet side.

According to a third aspect of the present invention, in the first aspect, a small-diameter tube portion having a smaller tube inner diameter than the other portion of the tube is formed on the refrigerant inlet side of the heat storage coil during the heat storage operation. It is.

In a fourth aspect based on the second aspect, the length of the heat storage coil from the refrigerant inlet to the branch portion during the heat storage operation is set to the length from the refrigerant inlet to the refrigerant outlet of the heat storage coil. The length is set to 3/10 to 5/10.

A regenerative air conditioner according to a fifth aspect of the present invention comprises a compressor, a heat source device side heat exchanger, a first expansion device, a second expansion device, and a use side heat exchanger which are sequentially connected. A main refrigerant circuit, and a heat storage utilization circuit that branches off from a pipe on the compressor suction side of the main refrigerant circuit and joins a pipe between the first throttle device and the second throttle device of the main refrigerant circuit via a refrigerant pump and a heat storage coil. In a regenerative air-conditioning apparatus including a heat storage coil and a heat storage tank that stores a heat storage medium, the heat storage coil has a pipe cross-sectional area on a refrigerant outlet side during a heat storage cooling operation that uses cold heat stored in the heat storage medium. It is smaller than the pipe cross-sectional area of the other parts.

In a sixth aspect based on the fifth aspect, the heat storage coil has a structure in which the heat storage coil is branched into a plurality of branch pipes at a branch portion located in the middle thereof, and a refrigerant outlet during cooling operation utilizing heat storage. The cross-sectional area of the non-branched portion disposed on the refrigerant side is smaller than the total cross-sectional area of the branch pipe disposed on the refrigerant inlet side.

According to a seventh aspect of the present invention, in the fifth aspect, a small-diameter pipe portion having a pipe inner diameter smaller than that of the other portion is formed on the refrigerant outlet side of the heat storage coil during the cooling operation using heat storage. It was done.

In an eighth aspect based on the sixth aspect, the length of the heat storage coil from the branch portion to the refrigerant outlet during the cooling operation utilizing heat storage is defined by the distance from the refrigerant inlet to the refrigerant outlet of the heat storage coil. The length is set to 3/10 to 5/10 of the length.

[0014]

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

Embodiment 1 of the Invention The heat storage device according to the first embodiment will be described with reference to FIG. As shown in the figure, the heat storage device A includes a compressor 1, a heat source device side heat exchanger 2, a first expansion device (an expansion device) 3, and a heat storage coil 10.
and a heat storage tank 9 containing a heat storage coil 10 a and a heat storage medium (for example, water) 8. Refrigerant circuit 2
1, a second switch 11 is provided in a refrigerant pipe between the heat storage coil 10a and the compressor 1. In FIG. 1,
Since the regenerative heat exchanger B including the regenerator A is also shown, other components than those described above are also shown, which will be described later.

The heat storage coil 10a is composed of a heat transfer tube, and the cross-sectional area of the pipe on the refrigerant inlet side (cross-sectional area of the refrigerant flow path in the pipe) during the heat storage operation for cooling the heat storage medium 8 is smaller than the cross-sectional area of the pipe in the other part. Is also reduced. More specifically, the heat storage coil 10 according to the first embodiment will be described.
As shown in FIG. 2, a plurality of (a 2 in this case) are present at the branch portion 31 located halfway from one end to the other end thereof.
The present invention has a structure branched into branch pipes 32, 32).
Then, the pipe cross-sectional area of the non-branch portion 33 from one end to the branch portion 31 is equal to the two branch pipes 32, 32 ahead of the branch portion 31.
Is smaller than the sum of the cross-sectional areas. (For example, when the non-branch portion 33 and each branch pipe 32 are formed of heat transfer tubes of the same standard, the pipe cross-sectional area of the non-branch portion 33 is
It is １ ／ of the total of the cross-sectional areas of the tubes. )

Such a heat storage coil 10a arranges the non-branched portion 33 on the refrigerant inlet side (closer to the first expansion device 3) during the heat storage operation, and connects the branch pipes 32, 32 to the refrigerant outlet side during the heat storage operation. (Close to the compressor 1), and is interposed in the refrigerant circuit 21.

Next, the operation of the heat storage device A will be described. At night, during the heat storage operation in which cold heat is stored in the heat storage tank 9, the high-temperature and high-pressure gas refrigerant discharged from the compressor 1 flows into the heat source device side heat exchanger 2 and is cooled and condensed and liquefied by air at normal temperature. . The refrigerant flowing out of the heat source unit side heat exchanger 2 is decompressed by the first expansion device 3 and then the heat storage coil 10
a, where heat exchange between the refrigerant inside the pipe and the heat storage medium 8 outside the pipe is performed. Then, the refrigerant that has cooled the heat storage medium 8 is vaporized and gasified, flows out of the heat storage coil 10a, passes through the second switch 11, and is sucked into the compressor 1.

Here, the operation and effect of using the heat storage coil 10a will be described in comparison with a conventional example with reference to FIG. During the heat storage operation, a low-temperature and low-pressure gas-liquid two-phase refrigerant (or liquid refrigerant) flows through the pipe near the refrigerant inlet of the heat storage coil, so that the conventional cross-sectional area shown in FIG. In the case of the heat storage coil 10, the flow rate of the refrigerant at the refrigerant inlet side decreases as indicated by the solid line in the graph of FIG. 3A, so that the heat transfer coefficient in the pipe at this portion decreases, and the heat exchange rate also decreases. It becomes smaller on the entrance side.

On the other hand, in the heat storage coil 10a of the first embodiment shown in FIG. 3C, the pipe cross-sectional area on the refrigerant inlet side is relatively small, and the pipe cross-sectional area on the refrigerant outlet side is relatively small. As shown by the dashed line in the graph of FIG. 3A, the flow rate of the refrigerant near the refrigerant inlet through which the low-temperature, low-pressure gas-liquid two-phase refrigerant (or liquid refrigerant) flows through the pipe is shown. Is faster than before. Therefore, the heat transfer coefficient in the pipe in this part is improved, and the heat exchange rate (heat transmission rate)
Also improve. Further, a branch portion 31 is provided at a position where the degree of dryness of the refrigerant is increased to some extent by heat exchange with the heat storage medium 8,
Since the pipe cross-sectional area is large from here to the refrigerant outlet, an increase in flow velocity due to evaporation and expansion of the refrigerant is suppressed.
Therefore, an increase in pressure loss in this portion is also suppressed.

As described above, in the first embodiment, since the heat exchange rate at the inlet side of the heat storage coil where the degree of dryness of the refrigerant is small can be increased, the same transfer as that of the conventional heat storage coil 10 can be achieved. By using the heat storage coil 10a having a heat area, it is possible to obtain a larger heat exchange capacity (heat storage capacity) than before.

Embodiment 2 of the Invention In the heat storage device according to the second embodiment, the heat storage coil 10 according to the first embodiment is used.
Instead of a, a heat storage coil 10b shown in FIG. 4 is used. The other configuration of the refrigerant circuit and the like are the same as those in the first embodiment, and thus the description thereof is omitted.

The heat storage coil 10b is composed of a small-diameter tube portion 34 from one end to the middle. The small diameter pipe section 34
This is a portion where the inner diameter of the pipe is smaller than the inner diameter of the other portion 35. Such a heat storage coil 10b is interposed in the refrigerant circuit 21 in a state where the small-diameter tube portion 34 is disposed on the refrigerant inlet side (closer to the first expansion device 3) during the heat storage operation.

In the second embodiment, by using the above-described heat storage coil 10b, the pipe on the refrigerant inlet side (small-diameter pipe section 34) through which the low-temperature, low-pressure, low-dryness refrigerant flows during the heat storage operation for cooling. Since the cross-sectional area is smaller than the cross-sectional area of the pipe of the other portion 35, the flow velocity of the refrigerant at the refrigerant inlet side can be increased, and the same effect as in the first embodiment can be obtained.

Embodiment 3 of the Invention In the heat storage device according to the third embodiment, a refrigerant circuit and a heat storage coil 10a that are basically the same as those in the first embodiment are used, and thus the description will be made with reference to FIGS. The feature of the third embodiment is that the branch portion 3 of the heat storage coil 10a
1 is specified.

That is, here, the length from the refrigerant inlet 36 to the branch portion 31 during the heat storage operation of the heat storage coil 10a is changed from the refrigerant inlet 36 to the refrigerant outlet 3 of the heat storage coil 10a.
The length is set to 3/10 to 5/10 of the length up to 7. In general, the heat storage coil has a meandering bent shape, but the “length” referred to here is a length measured by following the bent shape of the heat storage coil, In other words, it is the length when the bent heat storage coil is straightened. Further, in this embodiment, there are two branch pipes 32, but the length of the branch pipes 32 from the branch part 31 to the refrigerant outlet 37 is the same for both the branch pipes 32.

Next, the effect of the third embodiment will be described. First, in the heat storage coil 10a of FIG. 2, the position of the branch portion 31 was moved from the refrigerant inlet 36 side to the refrigerant outlet 37 side on the assumption that the entire coil length from the refrigerant inlet 36 to the refrigerant outlet 37 was constant. The change of the heat exchange rate, the heat transfer area, and the heat storage capacity in this case will be described with reference to FIG. In each of the graphs of FIGS. 5A, 5B, and 5C, the numbers on the horizontal axis represent the length from the refrigerant inlet 36 to the branch 31 (that is, the non- A value obtained by dividing the length of the branch portion 33 by the length from the refrigerant inlet 36 to the refrigerant outlet 37 (that is, the total length of the heat storage coil 10a) is shown.

As shown in FIG. 5B, the heat storage coil 1
0a, the closer the branch portion 31 is to the refrigerant outlet 37 (that is, the non-branch portion 33 having a smaller pipe cross-sectional area).
The higher the ratio of occupied) increases. Also,
Conversely, the total heat transfer area of the heat storage coil 10a decreases as the branch portion 31 approaches the refrigerant outlet 37. When the total heat transfer area is A, the average heat exchange rate is K, and the temperature difference between the heat storage medium (water) and the refrigerant for heat exchange is ΔT, the heat storage capacity (heat capacity) represented by A × K × ΔT Exchange capacity)
Indicates that the value on the horizontal axis of the graph is 4 as shown in FIG.
The maximum value is obtained when the branch portion 31 is located at a position where / 10, and decreases before and after that. However, since the decrease is not rapid, it can be said that if the branch portion 31 is within the range where the above value is 3/10 to 5/10, almost the maximum heat storage capacity is exhibited.

From the above, this Embodiment 3
By setting the length from the refrigerant inlet 36 to the branch portion 31 of the heat storage coil 10a to 3/10 to 5/10 of the length from the refrigerant inlet 36 to the refrigerant outlet 37 as shown in FIG. Using a heat storage coil having a heat area equivalent to that of the related art, it is possible to exhibit a particularly large heat storage capacity. Further, as can be seen from the graph of FIG. 5C, the pressure loss in that case is relatively small, so that no adverse effect due to the increase in the pressure loss can be avoided.

Embodiment 4 of the Invention Hereinafter, a regenerative air conditioner according to Embodiment 4 of the present invention will be described. FIG.
As shown in the figure, the regenerative air conditioner B is configured by sequentially connecting a compressor 1, a heat source device side heat exchanger 2, a first expansion device 3, a second expansion device 4, and a use side heat exchanger 5. The main refrigerant circuit 22 is branched from a gas pipe (refrigerant pipe) on the suction side of the compressor 1 of the main refrigerant circuit 22, and sequentially passes through a refrigerant pump 6, a first switch 7, and a heat storage coil 10a. A heat storage utilization circuit 23 that joins a liquid pipe (refrigerant pipe) between the first expansion device 3 and the second expansion device 4 of the circuit 22 is provided. Further, a branch from a gas pipe (refrigerant pipe) between the first switch 7 and the heat storage coil 10a of the heat storage utilization circuit 23, and a suction-side gas pipe (refrigerant pipe) of the compressor 1 through the second switch 11. ), And a branch from a discharge gas pipe (refrigerant pipe) between the refrigerant pump 6 and the first switch 7 of the heat storage utilization circuit 23 and the third switch 12
And a second connection pipe 25 that joins a discharge gas pipe (refrigerant pipe) between the compressor 1 of the main refrigerant circuit 22 and the heat source unit side heat exchanger 2 through the heat storage coil 10 a and the heat storage medium 8. And a heat storage tank 9 for housing.

The regenerative air conditioner B includes the regenerator A described in the first embodiment. The regenerative air conditioner B includes the regenerative coil A and other components such as the regenerative coil for cooling. The flow and the like of the refrigerant in the operation are the same as those in the first embodiment, and the description is omitted.

Next, the operation of the regenerative air conditioner B will be described. There are two patterns of daytime heat storage cooling operation. The first pattern is the heat storage coil 10a.
A cooling operation using only the condenser as the condenser, and another pattern is a combined cooling operation using the heat storage coil 10a and the heat source unit side heat exchanger 2 as the condenser.

In the cooling operation, the compressor 1 and the refrigerant pump 6 are operated with the first expansion device 3 and the second switch 11 closed. After passing through the third switch 12, the high-temperature and high-pressure gas refrigerant discharged from the compressor 1 merges with the high-temperature and high-pressure gas refrigerant discharged from the refrigerant pump 6 and passes through the first on-off valve 7 to the heat storage coil. It flows into 10a, is cooled by the heat storage medium 8, and is condensed and liquefied. The liquid refrigerant flowing out of the heat storage coil 10a is decompressed by the second expansion device 4, and then flows into the use-side heat exchanger 5. Then, the refrigerant evaporates and gasifies in the use side heat exchanger 5, flows out, and is sucked into the compressor 1 and the refrigerant pump 6.

On the other hand, in the combined cooling operation, the second switch 11
The compressor 1 and the refrigerant pump 6 are operated with the third switch 12 closed. The high-temperature and high-pressure gas refrigerant discharged from the compressor 1 flows into the heat source device side heat exchanger 2, and is cooled and condensed and liquefied by air at normal temperature. The refrigerant flowing out of the heat source unit side heat exchanger 2 is decompressed by the first expansion device 3. The high-temperature and high-pressure gas refrigerant discharged from the refrigerant pump 6 flows into the heat storage coil 10a via the first switch 7, and is cooled and condensed and liquefied by the heat storage medium 8. Then, the liquid refrigerant on the heat storage utilization circuit 23 side joins with the liquid refrigerant on the main refrigerant circuit 22 side depressurized by the first expansion device 3, and the merged refrigerant is decompressed by the second expansion device 4. , Flows into the use side heat exchanger 5. Then, the refrigerant evaporates and gasifies, flows out of the use side heat exchanger 5, and is sucked into the compressor 1 and the refrigerant pump 6.

As described above, in the thermal storage type air conditioner B, the thermal storage coil 10a shown in FIG. 2 is used as the thermal storage coil. However, during the cooling operation using the heat storage (during the cooling operation and the combined cooling operation) as described above, the flow direction of the refrigerant flowing through the heat storage coil 10a is as shown by the broken arrow in FIG. It is the opposite direction of time. That is, the refrigerant first flows into each branch pipe 32, merges at the branch part 31, and then flows out through the non-branch part 33. Therefore, the heat storage coil 10a
Has a configuration in which the cross-sectional area of the pipe on the refrigerant outlet side is smaller than the cross-sectional areas of the pipes in other portions.

Here, the operation and effect of using the heat storage coil 10a will be described with reference to FIG. 6 in comparison with a conventional example. During the cooling operation using heat storage, a high-temperature and high-pressure refrigerant having a high dryness flows from the compressor 1 and the refrigerant pump 6 near the refrigerant inlet of the heat storage coil.
Since the refrigerant gradually condenses and liquefies due to heat exchange with the refrigerant, a refrigerant having a low dryness flows through the pipe near the refrigerant outlet of the heat storage coil. Therefore, as shown in FIG.
When the conventional heat storage coil 10 having a constant cross-sectional area over the entire length is used, the flow rate of the refrigerant decreases at the refrigerant outlet side as shown by the solid line in the graph of FIG. And the heat exchange rate also decreases on the refrigerant outlet side.

On the other hand, in the case of the heat storage coil 10a shown in FIG. 6C, the pipe cross-sectional area on the refrigerant inlet side is relatively large and the pipe cross-sectional area on the refrigerant outlet side is relatively small. As shown by the dashed line in the graph of FIG.
The refrigerant flow velocity near the refrigerant outlet where the low-temperature, low-pressure, low-dryness gas-liquid two-phase refrigerant flows through the pipe becomes higher than before. Therefore, the heat transfer coefficient in the pipe in this portion is improved, and the heat exchange rate (heat transmission rate) is also improved. Further, the branch portion 31 is located at a position where the degree of dryness of the refrigerant is reduced to some extent by heat exchange with the heat storage medium 8, and the pipe cross-sectional area from the refrigerant inlet through which the refrigerant having a large degree of dryness flows to the branch portion 31 is large. The increase in pressure loss in this portion is suppressed.

As described above, in the fourth embodiment, since the heat exchange rate at the outlet side of the heat storage coil where the degree of dryness of the refrigerant is small can be increased, the power transfer equivalent to that of the conventional heat storage coil 10 can be achieved. By using the heat storage coil 10a having a heat area, a greater heat exchange capacity (condensing capacity) than before can be obtained, and the cooling capacity can be improved.

Further, since the tube cross-sectional area of the heat storage coil 10a is reduced in the middle, the internal volume of the entire coil is smaller than that of the conventional heat storage coil 10 as shown in FIG. Therefore, the use of the heat storage coil 10a also has the effect of reducing the total amount of refrigerant sealed in the refrigerant circuit of the entire heat storage type air conditioner.

Embodiment 5 of the Invention In the heat storage type air conditioner according to the fifth embodiment, the heat storage coil 10b shown in FIG.
Is used. The other configuration is the same as that of the fourth embodiment, and the description is omitted.

As described in the second embodiment, the heat storage coil 10b is constituted by the small-diameter tube portion 34 from one end to the middle. Such a heat storage coil 10b is interposed in the heat storage utilization circuit 23 in a state where the small-diameter tube portion 34 is arranged on the refrigerant outlet side during the heat storage utilization cooling operation.

Thus, the cross-sectional area of the refrigerant at the refrigerant outlet side (small-diameter pipe portion 34) through which the low-temperature and low-pressure refrigerant having a small dryness flows during the cooling operation utilizing the heat storage is made smaller than the cross-sectional area of the other portions 35. Therefore, the flow velocity of the refrigerant at the refrigerant outlet side can be increased, and the same effect as in the fourth embodiment can be obtained.

Embodiment 6 of the Invention In the heat storage type air conditioner according to the sixth embodiment, the heat storage coil 10a in which the position of the branch portion 31 is set is used as in the third embodiment. However, in the cooling operation using heat storage, the flow direction of the refrigerant in the heat storage coil is opposite to that in the heat storage operation described in the third embodiment. Therefore, in the sixth embodiment, heat is stored from the branch portion 31 of the heat storage coil 10a. Length to refrigerant outlet during use cooling operation (length of non-branched portion 33)
Is set to 3/10 to 5/10 of the length from the refrigerant inlet to the refrigerant outlet of the heat storage coil 10a.

Also in this case, the average heat exchange rate of the heat storage coil 10a is smaller than the total length of the heat storage coil 10a by the non-branch portion 3
As the ratio occupied by 3 increases, the total heat transfer area of the heat storage coil 10a decreases as the ratio occupied by the non-branched portion 33 increases.
And the total heat transfer area is A, the average heat exchange rate is K,
Assuming that the temperature difference between the heat storage medium (water) for heat exchange and the refrigerant is ΔT, the condensing capacity (heat exchange capacity) represented by A × K × ΔT is obtained by dividing the length of the non-branched portion 33 by 4/4 of the total coil length. 10
In the range where the length of the non-branched portion 33 is 3/10 to 5/10 of the entire length of the coil, a condensing ability substantially equal to the maximum condensing ability is exhibited.

From the above, this Embodiment 6
As described above, the length from the branch portion 31 of the heat storage coil 10a to the refrigerant outlet during the cooling operation utilizing heat storage is set to 3/10 to 5/10 of the length from the refrigerant inlet to the refrigerant outlet. Accordingly, a heat storage type air conditioner capable of exhibiting particularly large cooling capacity can be obtained using a heat storage coil having a heat transfer area equivalent to that of a conventional heat storage coil.

[0046]

As described above, in the heat storage device according to the first aspect of the present invention, the cross-sectional area of the heat storage coil at the inlet side of the heat storage coil is reduced during the heat storage operation.
By increasing the flow rate of the refrigerant in this portion, the heat transfer coefficient in the pipe can be improved, and the heat exchange rate between the refrigerant and the heat storage medium can be improved. Further, since the cross-sectional area of the tube is increased in other portions of the heat storage coil, a heat transfer area equivalent to that of the related art can be secured, and an increase in pressure loss can be suppressed. Therefore, it is possible to obtain a heat storage device that uses a heat storage coil having a heat transfer area equivalent to that of the related art and exhibits a larger heat storage capacity than the related art.

The heat storage device according to the second aspect of the present invention has a structure in which the heat storage coil is branched in the middle, so that the heat storage device having a heat storage capacity greater than that of the conventional heat storage device using a heat storage coil having the same heat transfer area as the conventional one. Is obtained.

In the heat storage device according to the third invention, a small-diameter pipe portion is formed on the refrigerant inlet side of the heat storage coil.
By using a heat storage coil having a heat transfer area equivalent to that of the conventional heat storage device, a heat storage device having a higher heat storage capacity than the conventional heat storage device can be obtained.

Further, the heat storage device according to the fourth invention has a structure in which the heat storage coil is branched on the way, and the length from the refrigerant inlet to the branch portion is 3/3 of the length from the refrigerant inlet to the refrigerant outlet. By setting 10 to 5/10,
A particularly large heat storage capacity can be exhibited by using a heat storage coil having a heat transfer area equivalent to that of a conventional heat storage coil.

Also, in the regenerative air conditioner according to the fifth invention, the cross-sectional area of the refrigerant at the outlet of the regenerative coil through which the refrigerant having a low dryness flows during the regenerative cooling operation is reduced.
By increasing the flow rate of the refrigerant in this portion, the heat transfer coefficient in the pipe can be improved, and the heat exchange rate between the refrigerant and the heat storage medium can be improved. Further, since the cross-sectional area of the tube is increased in other portions of the heat storage coil, a heat transfer area equivalent to that of the related art can be secured, and an increase in pressure loss can be suppressed. Therefore, it is possible to obtain a heat storage type air conditioner that uses a heat storage coil having a heat transfer area equivalent to that of the related art and exerts a greater cooling capacity than before. Furthermore, since the internal volume of the heat storage coil is reduced by reducing the pipe cross-sectional area on the heat storage coil refrigerant outlet side, the amount of refrigerant sealed in the refrigerant circuit can also be reduced.

Further, the heat storage air conditioner according to the sixth aspect of the present invention has a structure in which the heat storage coil is branched in the middle, so that the heat storage coil having the same heat transfer area as the conventional one is used, and the cooling capacity is higher than the conventional one. A regenerative air conditioner that is large and has a small amount of charged refrigerant can be obtained.

In the heat storage air conditioner according to the seventh invention, the small-diameter pipe portion is formed on the refrigerant outlet side of the heat storage coil.
A regenerative air conditioner having a larger cooling capacity and a smaller amount of enclosed refrigerant than before can be obtained.

The heat storage air conditioner according to the eighth invention has a structure in which the heat storage coil is branched on the way.
By setting the length from the branch portion to the coolant outlet to be 3/10 to 5/10 of the length from the coolant inlet to the coolant outlet, a particularly large cooling capacity can be exhibited.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing a heat storage device according to Embodiment 1 of the present invention and a heat storage type air conditioner according to Embodiment 4.

FIG. 2 is a perspective view of a heat storage coil used in Embodiments 1 and 4 of the present invention.

FIG. 3 is an explanatory diagram illustrating a change in a heat exchange rate and the like during a heat storage operation due to a change in a cross-sectional area of a heat storage coil.

FIG. 4 is a perspective view of a heat storage coil used in Embodiments 2 and 5 of the present invention.

FIG. 5 is an explanatory diagram illustrating a change in heat storage capacity and the like caused by changing a position of a branch portion of a heat storage coil.

FIG. 6 is an explanatory diagram illustrating a change in a heat exchange rate and the like during a cooling operation using heat storage due to a change in the cross-sectional area of the heat storage coil.

FIG. 7 is a perspective view of a conventional heat storage coil.

[Description of Signs] A heat storage device, B heat storage type air conditioner, 1 compressor,
2 heat source side heat exchanger, 3 first throttle device, 4 second throttle device, 5 use side heat exchanger, 6 refrigerant pump, 8 heat storage medium, 9 heat storage tank, 10a, 10b heat storage coil, 2
1 refrigerant circuit, 22 main refrigerant circuit, 23 heat storage utilization circuit, 31 branch, 32 branch pipe, 33 non-branch, 3
4 Small diameter pipe section.

Claims (8)

[Claims] 1. A compressor, a heat exchanger on a heat source side, a throttling device,
And a refrigerant circuit formed by sequentially connecting the heat storage coils, and a heat storage device including a heat storage tank that stores the heat storage coils and the heat storage medium, wherein the heat storage coils are disposed on a refrigerant inlet side during a heat storage operation for cooling the heat storage medium. A heat storage device characterized in that the pipe cross-sectional area is smaller than the pipe cross-sectional areas of other parts. 2. A heat storage coil having a structure in which the heat storage coil is branched into a plurality of branch pipes at a branch portion located in the middle thereof, and a pipe cross-sectional area of a non-branch portion disposed on a refrigerant inlet side during a heat storage operation is changed to a refrigerant outlet side. 2. The heat storage device according to claim 1, wherein the sum of the cross-sectional areas of the branch pipes disposed in the heat storage device is smaller than the total cross-sectional area. 3. The heat storage device according to claim 1, wherein a small-diameter pipe portion having a pipe inner diameter smaller than the pipe inner diameters of other portions is formed on the refrigerant inlet side of the heat storage coil during the heat storage operation. 4. The length of the heat storage coil from the refrigerant inlet to the branch portion during the heat storage operation is 3/10 to 5/10 of the length from the refrigerant inlet to the refrigerant outlet of the heat storage coil.
The heat storage device according to claim 2, wherein the length is set to: 5. A main refrigerant circuit in which a compressor, a heat source device side heat exchanger, a first expansion device, a second expansion device, and a use side heat exchanger are sequentially connected, and the compressor of the main refrigerant circuit. A heat storage utilization circuit that branches from a suction side pipe and joins a pipe between the first expansion device and the second expansion device of the main refrigerant circuit through a refrigerant pump and a heat storage coil; and the heat storage coil and the heat storage medium. In the regenerative air conditioner provided with a heat storage tank to house therein, the heat storage coil has a tube cross-sectional area on the refrigerant outlet side of the other portion in the heat storage utilizing cooling operation using the cold stored in the heat storage medium. A regenerative air conditioner characterized by having a smaller cross-sectional area. 6. A structure in which a heat storage coil is branched into a plurality of branch pipes at a branch part located in the middle thereof, and a pipe cross-sectional area of a non-branch portion disposed on a refrigerant outlet side during cooling operation using heat storage is changed by a refrigerant. The regenerative air conditioner according to claim 5, wherein the total cross-sectional area of the branch pipe disposed on the inlet side is smaller than the total cross-sectional area. 7. The heat storage type according to claim 5, wherein a small-diameter pipe portion having a pipe inner diameter smaller than the pipe inner diameters of the other portions is formed on the refrigerant outlet side of the heat storage coil during the heat storage utilizing cooling operation. Air conditioner. 8. The length of the heat storage coil from the branch portion to the refrigerant outlet during the cooling operation using heat storage is 3/10 to 5/10 of the length from the refrigerant inlet to the refrigerant outlet of the heat storage coil. The regenerative air conditioner according to claim 6, wherein the air conditioner is set to: