JPH0849937A - Regenerative air-conditioner - Google Patents

Abstract

PURPOSE:To obtain an air-conditioner which takes out effectively the quantity of heat stored in a heat storage tank in a daytime cooling operation. CONSTITUTION:In a regenerative air-conditioner comprising a primary-side refrigerating cycle and a secondary-side refrigerating cycle, a first control device CNT1 which makes a second flow regulating valve RV2 fully open when the quantity of heat stored in a heat storage tank STR becomes a prescribed value or below in a daytime cooling operation and in a heat storage tank operation mode for a relatively small indoor load, and executes the operation in the heat storage tank operation mode until the temperature of water of the heat storage tank becomes a specific value or above, is provided. Even in the case when the quantity of heat stored in the heat storage tank STR decreases, it is possible to take out effectively the quantity of the heat stored and to prevent a shortage of a cooling capacity for the indoor load, according to this constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner using air as a heat source, and has a heat storage function for utilizing nighttime electric power.
And a heat storage type air conditioner having a control function thereof.

[0002]

2. Description of the Related Art A heat storage type air conditioner has already been variously developed, for example, Japanese Patent Laid-Open No. 1-186.
There is a heat storage type air conditioner as disclosed in Japanese Patent No. 507.

The basic technique will be described below. As shown in FIG. 5, in the outdoor unit, the compressor 2, the four-way valve 3, the outdoor heat exchanger 4, the cooling and heating decompression device 5, and the first auxiliary heat exchanger 14a are sequentially connected in an annular shape to form a heat source side refrigeration cycle. The second auxiliary heat exchanger 14 that is integrally formed so as to exchange heat with the first auxiliary heat exchanger 14a.
b, the refrigerant adjustment tank 10, the refrigerant transfer pump PM, and the use side heat exchangers 15a and 15b are sequentially connected in an annular shape to form a use side refrigeration cycle.

Further, the heat storage heat exchanger 13a installed in parallel to the first auxiliary heat exchanger 14a in the heat source side refrigeration cycle and the second auxiliary heat exchanger 14b in the user side refrigeration cycle are installed in parallel. Heat exchanger 13 for heat radiation
b, and the heat storage tank STR which has the water 16 which is a heat storage material is installed.

In the heat source side refrigeration cycle, the three-way switching valves 17a and 17b are used to switch the circuit between the first auxiliary heat exchanger 14a and the heat storage heat exchanger 13a, and the second auxiliary heat exchanger is used in the user side refrigeration cycle. Switching of the circuit between the exchanger 14b and the heat radiation heat exchanger 13b is performed by the three-way flow valves 18a and 18b.

The operation of the heat storage type air conditioner configured as described above will be described. First, the night operation is an operation of only the heat source side refrigeration cycle, and in the heat source side refrigeration cycle, it is switched to the ice making operation and the heat storage (hot water) operation by the four-way valve 3, and during the ice making operation, in the direction of the solid line arrow in the figure. The refrigerant flows to form a cooling cycle, the outdoor heat exchanger 4 is a condenser, and the heat storage heat exchanger 13a in the heat storage tank is formed.
To act as an evaporator, and is stored as ice around the heat storage heat exchanger 13a in the heat storage tank.

Further, during the heat storage operation, the refrigerant flows in the direction of the broken line in the figure to form a heating cycle, and the outdoor heat exchanger 4
Is operated as an evaporator and the heat storage heat exchanger 13a in the heat storage tank acts as a condenser, and heat is stored as hot water in the heat storage tank STR via the heat storage heat exchanger 13a in the heat storage tank. In this case, the first auxiliary heat exchanger 14a is not used.

In this case, since the heat source side refrigeration cycle and the use side refrigeration cycle are separated and the refrigerants in both cycles do not mix, an appropriate amount of refrigerant to be filled can be maintained and the piping of the heat source side refrigeration cycle can be maintained. Since the length is short, even if the refrigerating machine oil in the compressor 2 flows out, it is easy to return and the reliability of the compressor 2 can be improved.

On the other hand, during the daytime operation, both the heat source side refrigeration cycle and the use side refrigeration cycle are operated.

Particularly, when the heat load on the user side is relatively large during one day, that is, at the time of so-called peak load, the first auxiliary heat exchanger 14 is switched by switching the three-way switching valves 17a and 17b.
a is communicated with the heat source side refrigeration cycle, and in the use side refrigeration cycle, the three-way flow valves 18a and 18b distribute the amount of refrigerant flowing into the second auxiliary heat exchanger 14b and the heat radiation heat exchanger 13b. There is.

At night, the heat exchanger 13 for radiating cold or hot heat stored in the heat storage material in the heat storage tank STR in the heat storage tank
heat is exchanged with the refrigerant in the use side refrigeration cycle via b,
Moreover, the refrigerant cooled or heated by the operation of the heat source side refrigeration cycle exchanges heat with the refrigerant in the utilization side refrigeration cycle via the second auxiliary heat exchanger 14b.

The refrigerant heat-exchanged by the two heat exchangers is conveyed by the refrigerant conveyance pump PM to the use side heat exchanger 15 of each indoor unit 12 and exchanges heat with the indoor air, thereby cooling each room. Or, perform heating.

Therefore, in this case, the cooling or heating capacity in the heat source side refrigerating cycle becomes almost the sum of the capacity of the heat source side refrigerating cycle and the heat radiating capacity in the heat radiating heat exchanger 13b of the heat storage tank STR, and Or the heating capacity increases.

As described above, the surplus power energy at night is converted to heat and stored, and the power is used during the daytime to suppress the power peak at the time of high load during the daytime, and to level the power usage. Can be achieved.

[0015]

However, in the above-mentioned conventional example, when the indoor cooling load is relatively small and only the heat storage tank STR of the utilization side (secondary side) refrigeration cycle is operated, the inside of the heat storage tank STR is When the water temperature rises along with the decrease in the heat storage amount, the temperature difference between the refrigerant inside the pipe and the water outside the pipe of the heat radiating heat exchanger 13b of the heat storage tank STR decreases, and the heat exchange amount in the heat storage tank STR decreases. The refrigerant supercooling degree at the outlet of the heat storage tank cannot be maintained.

Further, when the refrigerant supercooling degree at the outlet of the heat storage tank cannot be maintained, the refrigerant inside the heat-radiating heat exchanger 13b of the heat storage tank STR becomes a complete two-phase state.
The pressure loss in R increases, and the refrigerant circulation amount flowing through the heat radiation heat exchanger 13b of the heat storage tank STR decreases.

As a result, the heat storage amount in the heat storage tank STR cannot be effectively taken out, and the cooling capacity is insufficient.

Further, the indoor load is relatively large, the heat source side (primary side) refrigerating cycle is operated, and the heat radiating heat exchanger 13b of the heat storage tank STR of the user side (secondary side) refrigerating cycle and the second auxiliary. Similarly, when both heat exchangers 14b are operated, when the water temperature rises as the amount of heat stored in the heat storage tank STR decreases, the degree of refrigerant supercooling at the outlet of the heat storage tank cannot be maintained, and the heat for radiating heat from the heat storage tank STR cannot be maintained. The circulation amount of the refrigerant flowing through the exchanger 13b is reduced.

As a result, there is a drawback that the amount of heat stored in the heat storage tank STR cannot be effectively taken out and the cooling capacity becomes insufficient.

Therefore, according to the present invention, in each operation mode of the use side (secondary side) refrigeration cycle, by effectively taking out the amount of heat stored in the heat storage tank STR stored at night, the cooling capacity against the indoor load is insufficient. It is an object of the present invention to provide a heat storage type air conditioner that can be prevented.

[0021]

In order to achieve this object, a heat storage type air conditioner of the present invention has a compressor, a first four-way valve, and an outdoor heat exchanger connected in series, and a first heat exchanger. A primary-side refrigeration cycle in which the expansion valve and the primary-side heat exchange section of the refrigerant-refrigerant heat exchanger are connected in parallel to the second expansion valve and the primary-side heat exchange section of the heat storage tank; A pump unit including a second four-way valve and a refrigerant tank is connected to an indoor unit including an indoor heat exchanger and an indoor flow valve, and the first flow valve and the secondary heat of the refrigerant-refrigerant heat exchanger are connected to each other. The heat exchange unit comprises a second flow valve and a secondary side refrigeration cycle connected in parallel to the secondary side heat exchange unit of the heat storage tank. A water temperature detection device and a water level detection device are installed in the heat storage tank to store heat. It is equipped with a heat storage amount detector that calculates the heat storage amount of the heat storage tank from the water temperature and water level of the tank In the refrigeration cycle, a refrigerant-to-refrigerant heat exchanger operation mode in which the refrigerant flows through the secondary side heat exchange section of the refrigerant-to-refrigerant heat exchanger, and a heat storage tank operation mode in which the refrigerant flows through the secondary side heat exchange section of the heat storage tank, Refrigerant-to-refrigerant Refrigerant pair at the time of cooling operation is provided with a mode controller that switches each operation mode of simultaneous operation modes in which the refrigerant flows through both the secondary-side heat exchange section and the secondary-side heat exchange section of the heat storage tank The secondary heat exchange section outlet of the refrigerant heat exchanger and the subcooling degree detection device for detecting the refrigerant supercooling degree of the secondary heat exchange section outlet of the heat storage tank are provided.
In the case of the heat storage tank operation mode, and when the heat storage amount of the heat storage tank is less than or equal to a predetermined value, the second flow valve is fully opened, and operation in the heat storage tank operation mode is performed until the water temperature of the heat storage tank reaches or exceeds the predetermined value. It is provided with a first control device.

In the simultaneous operation mode and when the amount of heat stored in the heat storage tank falls below a predetermined value, the second flow valve is fully opened, and in the subsequent operation, the outlet of the secondary side heat exchange section of the heat storage tank. When it becomes impossible to maintain the degree of refrigerant subcooling of
A second control device is provided, in which the first flow valve is set to a predetermined opening degree or less and the operation in the simultaneous operation mode is performed until the heat storage tank water temperature becomes a predetermined value or more.

[0023]

The operation of the heat storage type air conditioner of the present invention having the above construction will be described below.

The nighttime heat storage operation (ice making operation) has the same operation as the conventional one, and therefore its explanation is omitted, and the daytime cooling operation will be described below.

First, in the daytime cooling operation, when the indoor load is relatively small, the mode control device operates in the heat storage tank operation mode.

At this time, the primary side refrigeration cycle does not operate because the compressor is not operated. Also, in the secondary side refrigeration cycle, the refrigerant exchanges heat with the heat storage material in the heat storage tank via the secondary heat exchange section of the heat storage tank, and after cooling itself to become a liquid refrigerant, the refrigerant is transferred to the room by the refrigerant transfer pump. It is sent to the unit to cool the room.

When the indoor load further increases, the mode control device operates in the simultaneous operation mode.

At this time, by operating the compressor of the primary side refrigeration cycle, the refrigerant of the secondary side refrigeration cycle is cooled via the primary side heat exchange section of the refrigerant-refrigerant heat exchanger.

Further, in the secondary side refrigeration cycle, the refrigerant is cooled through the secondary side heat exchange section of the heat storage tank and the secondary side heat exchange section of the refrigerant-refrigerant heat exchanger, and becomes itself a liquid refrigerant. After that, it is sent to the indoor unit by the refrigerant transfer pump to cool the room.

At this time, in the secondary side refrigeration cycle, the secondary side heat exchange section of the refrigerant-refrigerant heat exchanger and the heat storage tank 2 are provided.
The amount of refrigerant circulated to the secondary heat exchange unit is the first flow valve and the second flow valve.
The flow rate valves are controlled so that the refrigerant has a predetermined degree of supercooling.

By operating in this manner, it becomes possible to utilize the heat storage at night and perform the cooling operation corresponding to the indoor load.

Further, in the heat storage tank operation mode in which the indoor load is relatively small, the second flow valve is fully opened by the first control device when the heat storage amount of the heat storage tank becomes equal to or less than the predetermined value, and the heat storage tank is opened. The operation in the heat storage tank operation mode is performed until the water temperature reaches or exceeds the predetermined value.

As a result, the amount of refrigerant circulating in the secondary side heat exchange section of the heat storage tank increases, and the heat transfer coefficient inside the secondary side heat exchange section tube of the heat storage tank improves accordingly. It is possible to increase the amount of heat exchange between the refrigerant inside the tube and the water as the heat storage material in the secondary side heat exchange section.

Therefore, it is possible to prevent a shortage of the cooling capacity with respect to the indoor load. Further, in the simultaneous operation mode in which the indoor load is relatively large, the second control device causes the second flow valve to be fully opened when the heat storage amount in the heat storage tank becomes equal to or less than a predetermined value, and the heat storage is performed in the subsequent operation. When the refrigerant supercooling degree at the outlet of the secondary side heat exchange section of the tank cannot be maintained, the first flow valve is set to a predetermined opening or less to forcibly circulate the refrigerant in the heat storage tank so that the water temperature of the heat storage tank is a predetermined value or more. The operation is performed in the simultaneous operation mode until it becomes.

As a result, even when the amount of heat stored in the heat storage tank is reduced, it can be effectively taken out, and it is possible to prevent insufficient cooling capacity with respect to the indoor load.

As described above, in the heat storage tank operation mode in which the indoor load during daytime cooling is relatively small, when the heat storage amount decreases and the heat exchange amount in the heat storage tank decreases, the first control device stores the heat. In the tank operation mode, the heat storage amount in the heat storage tank is effectively taken out, and in the simultaneous operation mode in which the indoor load is relatively large, when the heat storage amount decreases and the heat exchange amount in the heat storage tank decreases, By effectively extracting the amount of heat stored in the heat storage tank by the control device in the simultaneous operation mode, it is possible to provide a heat storage type air conditioner capable of preventing insufficient cooling capacity with respect to the indoor load.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First embodiment of a heat storage type air conditioner according to the present invention
Embodiments will be described with reference to the drawings. It should be noted that the same configurations as those of the conventional one are denoted by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a refrigeration cycle diagram of the heat storage type air conditioner of the first embodiment of the present invention. In FIG. 1, the heat storage type air conditioner of the first embodiment according to the present invention comprises an outdoor unit 1, a heat storage tank STR, an indoor unit 12, and a pump unit PU.

The outdoor unit 1 includes a compressor 2, a first four-way valve 3a, an outdoor heat exchanger 4, a first expansion valve EXP1, a second expansion valve EXP2, a primary side heat exchange section 14a and a secondary side heat exchange. The refrigerant-to-refrigerant heat exchanger HEX including the portion 14b, the first flow valve RV1, and the second flow valve RV2.

The heat storage tank STR includes water 16 as a heat storage material, a primary side heat exchange section 13a of the heat storage tank, a secondary side heat exchange section 13b of the heat storage tank, a water temperature detection device 18, a water level detection device 19, and a heat storage amount detection. And the device CAL.

Also, a plurality of indoor units 12a, 12b
Is the indoor flow valves RVa and RVb, and the indoor heat exchanger 1
5a, 15b, and a pump unit P
U is composed of a refrigerant tank 10, a refrigerant transfer pump PM, and a second four-way valve 3b.

In the outdoor unit 1, the compressor 2, the first four-way valve 3a, the outdoor heat exchanger 4, and the first expansion valve EX.
P1 and the primary-side heat exchange section 14a of the refrigerant-refrigerant heat exchanger are connected in series, and the second expansion valve EXP2 and the primary-side heat exchange section 13a of the heat storage tank are connected to the first expansion valve EXP1 and the refrigerant. A primary side refrigeration cycle is formed by connecting in parallel to the primary side heat exchange section 14a of the heat exchanger for refrigerant.

Further, the pump unit PU, the indoor units 12a and 12b, the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger and the first flow valve RV1 are connected in series, and further the heat storage tank 2 is connected. Secondary heat exchange section 13b and second flow valve RV2
To the secondary side heat exchange section 14b of the refrigerant-to-refrigerant heat exchanger and the first
The flow rate valve RV1 is connected in parallel to form a secondary side refrigeration cycle.

Regarding the mode of the first four-way valve 3a,
The discharge side of the compressor 2 and the outdoor heat exchanger 4, and the compressor 2
When connecting the suction side and the heat storage tank STR, the cooling mode is
A case where the discharge side of the compressor 2 and the heat storage tank STR and the suction side of the compressor 2 and the outdoor heat exchanger 4 are connected to each other are defined as a heating mode.

Regarding the mode of the second four-way valve 3b, the refrigerant transfer pump PM discharge side and the indoor unit 12a,
12b and the refrigerant transfer pump PM suction side communicates with the outdoor unit 1 and the heat storage tank STR.
In the case where the refrigerant transfer pump PM discharge side is connected to the outdoor unit 1 and the heat storage tank STR, and the refrigerant transfer pump PM suction side is connected to the indoor units 12a and 12b, the heating mode is set.
Defined as

Regarding the first expansion valve EXP1 and the second expansion valve EXP2, the night mode is used when the first expansion valve EXP1 is fully closed and the second expansion valve EXP2 is set to a predetermined opening, and the second expansion valve EXP2 is opened. First expansion valve EX with EXP2 fully closed
The case where P1 is set to a predetermined opening is defined as the daytime mode.

Further, regarding the operation mode of the secondary side refrigeration cycle during the daytime cooling operation, the mode in which the refrigerant flows through the secondary side heat exchange section 14b of the refrigerant to refrigerant heat exchanger is the refrigerant to refrigerant heat exchanger operation mode, The mode in which the refrigerant flows through the secondary side heat exchange section 13b of the heat storage tank is the heat storage tank operation mode, and both the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger and the secondary side heat exchange section 13b of the heat storage tank are the refrigerant. The mode in which the current flows is defined as the simultaneous operation mode.

Each operation mode of the secondary side refrigeration cycle is switched by the mode controller MODE.

Here, SUB is the degree of refrigerant supercooling SC1 at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger in the cooling mode, and the refrigerant supercooling at the outlet of the secondary side heat exchange section 13b of the heat storage tank. This is a supercooling degree detection device that detects the degree SC2.

FIG. 2 is a flow chart showing the operation of the heat storage type air conditioner of the first embodiment of the present invention.

The operation of the heat storage type air conditioner configured as described above will be described below with reference to FIGS. 1 and 2.

However, since the present invention relates to the cooling operation in the daytime, the description of the night heat storage operation (ice making operation) and the heating operation will be omitted.

Since the present invention relates to the heat storage tank operation mode and the simultaneous operation mode in the daytime cooling operation, the description of the other operation modes (refrigerant-refrigerant heat exchanger operation mode) will be omitted.

Daytime cooling operation (heat storage tank operation mode); if the indoor load is relatively small, STEP 1 and STE
In P2, the mode controller MODE switches to the heat storage tank operation mode.

In STEP3, the refrigerant transfer pump PM starts to operate, and in STEP4, the control target range B of the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank.
(Lower limit value Bmin, upper limit value Bmax) is set, and the process proceeds to STEP5.

In STEP 5, when the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is smaller than the lower limit value Bmin of the control target range B, the refrigerant circulation amount in the heat storage tank STR is reduced. In order to increase the degree of refrigerant supercooling SC2 at the outlet of the secondary side heat exchange section 13b of the tank, STEP6
And the second flow valve RV2 is closed by a predetermined opening degree.

On the contrary, the refrigerant supercooling degree SC2 at the outlet of the secondary heat exchange section 13b of the heat storage tank is the lower limit value Bmin of the control target range B.
In the above case, the process proceeds to STEP 7, and when the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is larger than the upper limit value Bmax of the control target range B, the heat storage tank ST
The secondary side heat exchange section 1 of the heat storage tank is increased by increasing the refrigerant circulation amount of R.
In order to reduce the refrigerant supercooling degree SC2 at the 3b outlet, ST
The process moves to EP8, and the second flow valve RV2 is opened by a predetermined opening degree.

When the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is within the control target range B, the second flow valve RV2 does not operate.

However, the operation is continued in this way, and the heat storage tank S
When the water temperature rises as the amount of heat stored in TR decreases, the temperature difference between the refrigerant inside the pipe and the water outside the pipe of the secondary side heat exchange section 13b of the heat storage tank decreases, and the amount of heat exchange in the heat storage tank STR As a result, the refrigerant supercooling degree at the outlet of the secondary side heat exchange portion 13b of the heat storage tank cannot be maintained.

Further, if the degree of refrigerant supercooling at the outlet of the secondary side heat exchange section 13b of the heat storage tank cannot be maintained, the refrigerant inside the tube of the secondary side heat exchange section 13b of the heat storage tank becomes a complete two-phase state. In addition, the pressure loss in the heat storage tank STR increases, and the amount of refrigerant circulation flowing through the secondary heat exchange section 13b of the heat storage tank decreases.

As a result, the amount of heat stored in the heat storage tank STR cannot be effectively taken out, resulting in insufficient cooling capacity.

Therefore, in STEP 9, when it is detected by the heat storage amount detecting device CAL that the heat storage amount in the heat storage tank STR is equal to or less than the predetermined value, the process proceeds to STEP 10 and the heat storage amount in the heat storage tank STR should be used up. 2 flow valve RV2
The operation is performed with the opening degree of fully opened.

As a result, the secondary side heat exchange section 1 of the heat storage tank 1
Since the refrigerant circulation amount of 3b increases and the heat transfer coefficient inside the secondary side heat exchange section 13b of the heat storage tank increases accordingly,
A pipe inside refrigerant in the secondary side heat exchange section 13b of the heat storage tank;
The amount of heat exchange with the water 16, which is the heat storage material, can be increased.

Then, in STEP 11, the heat storage tank S
The operation in the heat storage tank operation mode is performed until the water temperature in TR becomes equal to or higher than a predetermined value.

Therefore, even when the amount of heat stored in the heat storage tank STR is reduced, it can be effectively taken out, and a shortage of the cooling capacity against the indoor load can be prevented.

Next, a second embodiment of the heat storage type air conditioner according to the present invention will be described with reference to the drawings.

FIG. 3 is a refrigeration cycle diagram of the heat storage type air conditioner of the second embodiment of the present invention, and FIG. 4 is a flow chart showing the operation of the heat storage type air conditioner of the same embodiment.

Daytime cooling operation (simultaneous operation mode); if the indoor load is relatively large, STEP1 and STEP
In 2, the mode controller MODE switches to the simultaneous operation mode.

In STEP3, the refrigerant transport pump PM and the compressor 2 start operating, and in STEP4, the control target range of the refrigerant supercooling degree SC1 at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger. A (lower limit value Amin, upper limit value Am
ax) and the control target range B (lower limit value Bmin, upper limit value Bmax) of the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank, and the process proceeds to STEP5.

In STEP 5, when the degree of refrigerant supercooling SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is smaller than the lower limit value Bmax of the control target range B, the refrigerant circulation amount in the heat storage tank STR is reduced to store heat. In order to increase the degree of refrigerant supercooling SC2 at the outlet of the secondary side heat exchange section 13b of the tank, STEP6
And the second flow valve RV2 is closed by a predetermined opening degree.

On the contrary, the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is the lower limit value Bmin of the control target range B.
In the above case, the process proceeds to STEP 7, and when the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank is larger than the upper limit value Bmax of the control target range B, the heat storage tank ST
The secondary side heat exchange section 1 of the heat storage tank is increased by increasing the refrigerant circulation amount of R.
In order to reduce the refrigerant supercooling degree SC2 at the 3b outlet, ST
The process moves to EP8, and the second flow valve RV2 is opened by a predetermined opening degree.

When the refrigerant supercooling degree SC2 at the outlet of the secondary heat exchange section 13b of the heat storage tank is within the control target range B, the second flow valve RV2 does not operate.

Then, in STEP 9, the degree of refrigerant supercooling SC at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger.
When 1 is smaller than the lower limit value Amin of the control target range A, the refrigerant circulation amount of the refrigerant-refrigerant heat exchanger HEX is reduced to reduce the refrigerant excess at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger. In order to increase the cooling degree SC1, the process proceeds to STEP10 and the first flow valve RV1 is closed by a predetermined opening degree.

On the contrary, when the refrigerant supercooling degree SC1 at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger is equal to or higher than the lower limit value Amin of the control target range A, the process proceeds to STEP11, and the refrigerant-refrigerant heat is further transferred. When the degree of refrigerant supercooling SC1 at the outlet of the secondary side heat exchange section 14b of the exchanger is larger than the upper limit value Amax of the control target range A, the refrigerant circulation amount of the refrigerant / refrigerant heat exchanger HEX is increased to increase the refrigerant pair. Secondary side heat exchange section 1 of refrigerant heat exchanger
In order to reduce the refrigerant supercooling degree SC1 at the 4b outlet, ST
The process moves to EP12, and the first flow valve RV1 is opened by a predetermined opening degree.

When the refrigerant supercooling degree SC1 at the outlet of the secondary side heat exchange section 14b of the refrigerant-refrigerant heat exchanger is within the control target range A, the first flow valve RV1 does not operate.

However, the operation is continued in this way, and the heat storage tank S
When the water temperature rises as the amount of heat stored in TR decreases, the temperature difference between the refrigerant inside the pipe and the water outside the pipe of the secondary side heat exchange section 13b of the heat storage tank decreases, and the amount of heat exchange in the heat storage tank STR As a result, the refrigerant supercooling degree at the outlet of the secondary side heat exchange portion 13b of the heat storage tank cannot be maintained.

Further, if the degree of refrigerant supercooling at the outlet of the secondary side heat exchange section 13b of the heat storage tank cannot be maintained, the refrigerant inside the tube of the secondary side heat exchange section 13b of the heat storage tank becomes a complete two-phase state. In addition, the pressure loss in the heat storage tank STR increases, and the amount of refrigerant circulation flowing through the secondary heat exchange section 13b of the heat storage tank decreases.

As a result, the amount of heat stored in the heat storage tank STR cannot be effectively taken out, resulting in insufficient cooling capacity.

Therefore, in STEP 13, when it is detected by the heat storage amount detecting device CAL that the heat storage amount in the heat storage tank STR is less than or equal to a predetermined value, the process proceeds to STEP 14 to use up the heat storage amount in the heat storage tank STR. The operation is performed by fully opening the second flow valve RV2.

Then, in STEP 15, when the refrigerant supercooling degree SC2 at the outlet of the secondary side heat exchange section 13b of the heat storage tank cannot be maintained, the process proceeds to STEP 16, and the opening degree of the first flow valve RV1 is set to a predetermined opening degree or less. As a result, the refrigerant is forcibly circulated in the heat storage tank STR, and the operation in the simultaneous operation mode is performed until the water temperature in the heat storage tank STR reaches or exceeds a predetermined value.

As a result, even when the heat storage amount in the heat storage tank STR is reduced, the heat storage amount in the heat storage tank STR is effectively taken out, and heat is also exchanged in the refrigerant-refrigerant heat exchanger HEX. It is possible to prevent a shortage of the cooling capacity even when the value is large.

As described above, during the daytime cooling operation,
In the heat storage tank operation mode in which the indoor load is relatively small, and when the heat exchange amount in the heat storage tank STR decreases, the first control device C
When the amount of heat stored in the heat storage tank STR is effectively taken out by the NT1 in the heat storage tank operation mode, and the amount of heat exchange in the heat storage tank STR decreases in the simultaneous operation mode in which the indoor load is relatively large, the second control device By effectively extracting the amount of heat stored in the heat storage tank STR by the CNT 2 in the simultaneous operation mode, it is possible to provide the heat storage type air conditioner capable of preventing the insufficient cooling capacity with respect to the indoor load.

[0083]

As described above, the present invention comprises the primary side refrigeration cycle and the secondary side refrigeration cycle through the refrigerant-refrigerant heat exchanger and the heat storage tank, and the heat storage amount decreases during the daytime cooling operation. Then, when the heat exchange amount in the heat storage tank decreases, the heat storage amount in the heat storage tank is effectively taken out by the first control device in the heat storage tank operation mode in which the indoor load is relatively small,
By effectively extracting the amount of heat stored in the heat storage tank by the second control device in the simultaneous operation mode in which the indoor load is relatively large, it is possible to provide a heat storage type air conditioner capable of preventing insufficient cooling capacity with respect to the indoor load. .

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram of a heat storage type air conditioner according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the heat storage type air conditioner of the same embodiment.

FIG. 3 is a refrigeration cycle diagram of a heat storage type air conditioner according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the heat storage type air conditioner of the same embodiment.

FIG. 5 is a refrigeration cycle diagram of a heat storage type air conditioner showing a conventional example.

[Explanation of symbols]

 2 Compressor 3a First four-way valve 3b Second four-way valve 4 Outdoor heat exchanger 12a, 12b Indoor unit 13a Primary heat exchange part of heat storage tank 13b Secondary heat exchange part of heat storage tank 14a Refrigerant-to-refrigerant heat exchange Primary side heat exchange part 14b Refrigerant-to-refrigerant heat exchanger secondary side heat exchange part 15a, 15b Indoor side heat exchanger RVa, RVb Indoor flow valve 18 Water temperature detection device 19 Water level detection device CAL Heat storage amount detection device STR Heat storage tank HEX Refrigerant-refrigerant heat exchanger PM Refrigerant transfer pump EXP1 First expansion valve EXP2 Second expansion valve RV1 First flow valve RV2 Second flow valve MODE mode control device SUB Supercooling degree detection device CNT1 First control device CNT2 No. 2 control device

Claims (2)

[Claims] 1. A compressor, a first four-way valve, and an outdoor heat exchanger are connected in series, and a first expansion valve and a primary-side heat exchange section of a refrigerant-refrigerant heat exchanger are connected to a second heat exchanger. A primary side refrigeration cycle connected in parallel to the expansion valve and the primary side heat exchange section of the heat storage tank, a pump unit consisting of a refrigerant transfer pump, a second four-way valve and a refrigerant tank, and an indoor side heat exchanger. An indoor unit including an indoor flow valve is connected, and the first flow valve and the secondary heat exchange part of the refrigerant-refrigerant heat exchanger are connected to the second flow valve and the secondary heat exchange part of the heat storage tank. And a secondary side refrigeration cycle connected in parallel, and a water temperature detecting device and a water level detecting device are installed in the heat storage tank,
A heat storage amount detection device that calculates the heat storage amount of the heat storage tank from the water temperature and the water level of the heat storage tank is provided, and in the secondary side refrigeration cycle during cooling operation, the refrigerant is used as the refrigerant for the secondary side heat exchange section of the refrigerant-refrigerant heat exchanger. Refrigerant-to-refrigerant heat exchanger operation mode, heat storage tank operation mode in which refrigerant flows through the secondary side heat exchange section of the heat storage tank, secondary side heat exchange section of refrigerant-to-refrigerant heat exchanger and secondary side of the heat storage tank A mode control device is provided for switching each operation mode of simultaneous operation modes in which the refrigerant flows through both the heat exchange parts, and further, the outlet of the secondary side heat exchange part of the refrigerant-refrigerant heat exchanger during the cooling operation, and the secondary of the heat storage tank. Equipped with a supercooling degree detection device that detects the degree of refrigerant supercooling at the outlet of the side heat exchange unit, and fully opens the second flow valve when in the heat storage tank operation mode and when the heat storage amount in the heat storage tank is below a predetermined value. As a result, in the heat storage tank operation mode until the water temperature of the heat storage tank exceeds a predetermined value Thermal storage type air conditioner having a first controller for rolling. 2. In the simultaneous operation mode, when the amount of heat stored in the heat storage tank is below a predetermined value, the second flow valve is fully opened, and in the subsequent operation, the outlet of the secondary side heat exchange section of the heat storage tank. If the refrigerant supercooling degree of
The heat storage type air conditioner according to claim 1, further comprising a second control device that operates in the simultaneous operation mode until the heat storage tank water temperature becomes equal to or higher than a predetermined value with the flow valve set to a predetermined opening or less.