JPH09152223A - Thermal storage type air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to rapidly suppress the abnormal rise of the pressure of a compressor by constituting a thermal storage heat exchanger which can be operated as a water-cooled condenser when the discharge or suction pressure of the compressor is abnormally raised at the time of cooling operation. SOLUTION: When the cooling operation is detected by cooling mode detecting means 18 in the thermal storage type air conditioner, the temperature of a heat storage material 9 is detected by heat storage material temperature detecting means 19, and the pressure of the suction or discharge unit of a compressor 2 is detected by compressor pressure detecting means 20. Then, when the detected pressure exceeds a prescribed pressure, storage heat use deciding means 21 judges that the pressure of the compressor 2 is overloaded, further judges that a thermal storage heat exchanger 8a can operate as a condenser when the material 9 temperature is a prescribed temperature or lower, opens an expansion valve 5b and a two-way valve NV2 by storage heat use drive means 22, and closes a two-way valve NV1. Thus, the exchanger 8a is operated as a water-cooled condenser, thereby rapidly suppressing the abnormal pressure rise of the compressor 2.

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.
The present invention relates to a heat storage type air conditioner having a heat radiation function and a control function thereof.

[0002]

2. Description of the Related Art Various types of regenerative air conditioners have already been developed.
There is a regenerative air conditioner as disclosed in JP-A-236.

The basic technique will be described with reference to FIG.
1, the outdoor unit 1 includes a compressor 2, a first four-way valve 3
a, heat source side heat exchanger 4, first expansion valve 5a, first switching valve K
V1, a refrigerant-to-refrigerant heat exchanger HEX comprising a first auxiliary heat exchanger 7a and a second auxiliary heat exchanger 7b, and a heat storage heat exchanger 8
and a heat storage tank STR composed of a heat exchanger 8b and a heat exchanger 8b.
2. It is composed of a refrigerant amount adjusting tank 11 and a refrigerant transport pump PM for transporting the refrigerant. Further, the plurality of indoor units 13a and 13b are configured by use-side heat exchangers 14a and 14b.

[0004] The heat source side refrigeration cycle includes a compressor 2,
A first four-way valve 3a, a heat source side heat exchanger 4, a first expansion valve 5a,
It comprises a first switching valve KV1, a first auxiliary heat exchanger 7a, and a heat storage heat exchanger 8a.

The use-side refrigeration cycle includes a second auxiliary heat exchanger 7b, a heat-dissipating heat exchanger 8b, and a second auxiliary heat exchanger 8b for switching the flow path of the refrigerant.
It comprises a switching valve KV2, a refrigerant amount adjusting tank 11, a refrigerant transport pump PM for transporting the refrigerant, and indoor units 13a and 13b.

Next, the refrigeration cycle will be described. This refrigeration cycle can be broadly divided into a cooling heat storage operation for making ice at night (or a heating heat storage operation for producing hot water) and a daytime cooling (or heating) operation.
The heating heat storage operation and daytime heating operation will be described only in the operation mode, and will not be described in detail.

A) Night heat storage operation In the heat source side refrigeration cycle, the heat storage tank STR operates,
The first switching valve KV1 is switched so that the refrigerant-to-refrigerant heat exchanger HEX does not operate. At this time, the refrigerant transport pump PM is stopped, and the use side cycle does not operate. The operation of the heat source side refrigeration cycle will be described below.

Regarding the mode of the first four-way valve 3a,
The case where the discharge side of the compressor 2 communicates with the heat source side heat exchanger 4 and the suction side of the compressor 2 communicates with the heat storage tank STR is a cooling mode.
A case in which the discharge side of the compressor 2 communicates with the heat storage tank STR, and the case where the suction side of the compressor 2 communicates with the heat source side heat exchanger 4 are defined as a heating mode.

As for the first switching valve KV1, the first STR circuit and the refrigerant-refrigerant heat exchanger H are set so that the heat storage tank STR and the first expansion valve 5a communicate with each other in the heat source side refrigeration cycle.
The setting for communicating the EX with the first expansion valve 5a is defined as a first HEX circuit.

A-1) Cooling heat storage operation The first four-way valve 3a is a cooling mode, the first expansion valve 5a is a predetermined opening degree, and the first switching valve KV1 is a first STR circuit. At this time, the high-temperature and high-pressure refrigerant sent from the compressor 2 is condensed in the heat source side heat exchanger 4 and decompressed by the first expansion valve 5a to be in a liquid or two-phase state, and heat exchange for heat storage in the heat storage tank STR is performed. After evaporating in the vessel 8a and absorbing heat from the water 9 as a heat storage material,
Return to the compressor 2.

As a result, cold water and ice are produced around the heat storage heat exchanger 8a of the heat storage tank STR, and heat is stored.

B) Daytime operation During the daytime cooling (or heating) operation, the compressor 2, the heat source side heat exchanger 4, the refrigerant-refrigerant heat exchanger HEX, the refrigerant transfer pump PM, and the use side heat exchangers 14a, 14b. Can be divided into a normal cooling (or normal heating) operation in which the above-mentioned action is applied and a peak load cooling (or peak load heating) operation in which the heat storage tank STR is added to the normal cooling (or normal cooling and heating) operation.

These operation patterns are selectively used according to the amount of heat stored in the heat storage tank STR during indoor load or night heat storage operation. For example, when the indoor load in the early morning is small, the normal cooling operation is performed, when the indoor load at noon is large, the operation is switched to the peak load cooling operation, and when the amount of heat stored in the heat storage tank STR is exhausted, the normal cooling operation is switched to the normal cooling operation again. Peak load.

The operation of the refrigerating cycle in these operation patterns will be described below. Also, the second switching valve K
Regarding V2, the setting for communication between the refrigerant-to-refrigerant heat exchanger HEX and the use-side heat exchangers 14a and 14b in the use-side refrigeration cycle is set in the second HEX circuit and the refrigerant-to-refrigerant heat exchanger HEX.
The setting for communicating the heat storage tank STR with the use side heat exchangers 14a and 14b is defined as a second (HEX + STR) circuit.

B-1) Normal cooling operation In the heat source side refrigeration cycle, the first four-way valve 3a is set in the cooling mode,
The first expansion valve 5a is set to a predetermined opening degree, and the first switching valve KV1 is set to the first opening degree.
HEX circuit. At this time, the high-temperature and high-pressure refrigerant sent from the compressor 2 is condensed in the heat source side heat exchanger 4 and decompressed by the first expansion valve 5a to be in a liquid or two-phase state, and is sent to the first auxiliary heat exchanger 7a. To return to the compressor 2.

The use side refrigeration cycle is the second switching valve KV2.
Is a second HEX circuit. At this time, the gas refrigerant flowing out of the second switching valve KV2 is condensed in the second auxiliary heat exchanger 7b to become a liquefied or two-phase refrigerant, and the refrigerant amount adjustment tank 1
1 and is sent to the use side heat exchangers 14a and 14b by the refrigerant transport pump PM. Here, cooling is performed by absorbing heat from room air.

After that, the refrigerant passes through the second switching valve KV2 again and flows into the second auxiliary heat exchanger 7b.

B-2) Peak load cooling operation This is an operation in which the heat radiating heat exchanger 8b of the heat storage tank STR is added to the normal cooling operation of B-1.

Since the heat source side refrigeration cycle is the same as that in the normal cooling operation of B-1, the description will be omitted and the use side refrigeration cycle will be described.

The use side refrigeration cycle is the second switching valve KV2.
Is a second (HEX + STR) circuit. At this time, the gas refrigerant flowing out of the use side heat exchangers 14a and 14b
It flows into the switching valve KV2. The valve opening degree of the second switching valve KV2 is adjusted according to the capacities of the heat storage tank STR and the refrigerant-refrigerant heat exchanger HEX.

A part of the gas refrigerant is sent from the second switching valve KV2 to the second auxiliary heat exchanger 7b, and the first auxiliary heat exchanger 7a.
And is sent to the refrigerant amount adjusting tank 11. The remaining gas refrigerant is sent to the heat exchanger for heat dissipation 8b,
The cold water and ice formed around the heat storage heat exchanger 8a in the cooling heat storage operation at night cools and condenses the liquid refrigerant to be sent to the refrigerant amount adjustment tank 11.

At this time, the amount of heat radiated from the heat storage tank is predetermined by air conditioning load prediction control or the like, and the valve of the second switching valve KV2 is opened / closed according to the target degree of supercooling SC1 at the outlet of the heat radiating heat exchanger 8b. The heat exchanger 8 for heat dissipation
It is controlled by adjusting the amount of circulating refrigerant flowing into b.

The liquid refrigerant in the refrigerant amount adjusting tank 11 is transferred to the use side heat exchangers 14a, 14a by the refrigerant transfer pump PM.
b to absorb heat from room air, evaporate and cool.

After that, the gasified refrigerant passes through the second switching valve KV2 again and flows into the second auxiliary heat exchanger 7b and the heat radiation heat exchanger 8b.

In this case, the capacity of the heat source side refrigeration cycle,
This is almost the sum of the heat dissipation capacity of the heat storage tank STR and the heat dissipation capacity of the heat exchanger 8b, and the cooling capacity is increased.

The normal cooling operation and the peak load cooling operation are selectively used according to the amount of heat stored in the heat storage tank STR in the indoor load or night heat storage operation. For example, when the indoor load in the early morning is small, the normal cooling operation is performed, when the indoor load at noon is large, the operation is switched to the peak load cooling operation, and when the amount of heat stored in the heat storage tank STR is exhausted, the normal cooling operation is switched to the normal cooling operation again. Peak load.

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

This prior art example is composed of a single heat source side refrigeration cycle and a user side cycle, and the heating / cooling capacity per heat source side refrigeration cycle is roughly estimated to be about 6
0 kW: Air conditioning is possible for a floor area equivalent to about 500 square meters. For a large-scale building having a total floor area exceeding 1,000 square meters, a plurality of heat source-side refrigeration cycles and a use-side cycle are configured to cope with the air conditioning load.

[0029]

However, in the cooling operation using the refrigerant-to-refrigerant heat exchanger HEX in the above-mentioned conventional example, when the outside air temperature is extremely high, such as on a midsummer day, or when the indoor load becomes significantly large. In the above, since the discharge or suction pressure of the compressor 2 exceeds the specification abnormally, there is a problem that the life of the compressor 2 is shortened and, in some cases, a failure occurs.

In view of the above-mentioned drawbacks, the present invention has the following advantages when the discharge or suction pressure of the compressor rises abnormally during cooling:
By operating the heat storage heat exchanger as a water-cooled condenser,
The reliability of the compressor is secured by suppressing an abnormal rise in the pressure of the compressor, and the cold heat of the heat storage tank is effectively used.

[0031]

The technical means of the present invention for solving the above-mentioned problems is a compressor, a first four-way valve, a heat source side heat exchanger, a first expansion valve, and a first auxiliary heat exchange. And a first auxiliary heat exchanger of the refrigerant-to-refrigerant heat exchanger, which is composed of a heat exchanger and a second auxiliary heat exchanger, are sequentially connected in an annular shape, and a second expansion valve, a heat storage heat exchanger, and a heat radiation heat exchanger Refrigerant on the heat source side in which a heat storage heat exchanger of a heat storage tank made of a heat storage material is connected in series to a series connection portion of the first expansion valve and the first auxiliary heat exchanger. A cycle, a pump unit in which a refrigerant transfer pump, a second four-way valve and a refrigerant tank are sequentially connected in an annular shape, a plurality of indoor units including an indoor flow valve and a utilization side heat exchanger, and the second auxiliary heat exchanger And the first flow valve are connected in series, the heat radiating heat exchanger and the second flow valve are connected to each other. A first two-way valve, which is composed of a utilization side refrigeration cycle formed by annularly connecting those connected in parallel and those connected in parallel, and located between the heat storage heat exchanger and the first auxiliary heat exchanger. And a bypass having one end between the heat storage heat exchanger and the first two-way valve and the other end located between the first four-way valve and the heat source side heat exchanger, and in the middle of the bypass. A cooling mode detecting means having a second two-way valve for detecting a cooling operation mode using the second auxiliary heat exchanger, and a heat storage material temperature detecting means for detecting the temperature of the heat storage material. And a compressor pressure detecting means for detecting the pressure of the suction part or the discharge part of the compressor, and determining that the pressure of the compressor is overloaded, and acting the heat storage heat exchanger as a condenser. Heat storage utilization determining means for determining that it is possible, the second expansion valve, and the first In the case where the cooling operation is constituted by a one-way valve and a heat storage utilization drive means for driving the second two-way valve, and the cooling mode detection means detects a cooling operation in a cycle using the second auxiliary heat exchanger. To
The heat storage material temperature detection means detects the temperature of the heat storage material, the compressor pressure detection means detects the pressure of the suction portion or the discharge portion of the compressor, and the heat storage utilization determination means detects the suction portion of the compressor or If the pressure of the discharge part exceeds a predetermined first predetermined pressure, it is judged that the pressure of the compressor is overloaded, and if the temperature of the heat storage material is equal to or lower than the predetermined first predetermined temperature. If there is, it is judged that the heat storage heat exchanger can act as a condenser, and the heat storage utilization drive means opens the second expansion valve and the second two-way valve and closes the first two-way valve. Is.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The heat storage type air conditioner of the present invention detects the temperature of the heat storage material when the cooling mode detection means detects the cooling operation in the cycle using the second auxiliary heat exchanger. Means for detecting the temperature of the heat storage material, compressor pressure detecting means for detecting the pressure of the suction portion or discharge portion of the compressor, and heat storage utilization determining means for predetermining the pressure of the suction portion or discharge portion of the compressor. If it exceeds the first predetermined pressure, it is judged that the pressure of the compressor is overloaded, and if the temperature of the heat storage material is below a predetermined first predetermined temperature, the heat storage heat exchanger. Is determined to be operable as a condenser, the heat storage utilization drive means opens the second expansion valve and the second two-way valve, and closes the first two-way valve.

By the above operation, when the discharge or suction pressure of the compressor rises abnormally during the cooling operation, the heat exchanger for heat storage acts as a water-cooled condenser so that the pressure of the compressor rises abnormally. Since it is possible to quickly suppress the above, it is possible to ensure the reliability of the compressor and to effectively utilize the cold heat of the heat storage tank.

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same components as those of the conventional one will be designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a refrigeration cycle diagram of an embodiment of the present invention. The heat storage type air conditioner of the present embodiment includes an outdoor unit 1 ′, a pump unit PU, a plurality of indoor units 13a and 13b, and a heat storage tank STR.

The outdoor unit 1'includes a compressor 2, a first four-way valve 3a, a heat source side heat exchanger 4, a first expansion valve 5a, a second expansion valve 5b, a first auxiliary heat exchanger 7a and a second auxiliary heat. Exchanger 7b
A refrigerant-to-refrigerant heat exchanger HEX, a first flow valve RV1 for the second auxiliary heat exchanger 7b, a second flow valve RV2 for the heat radiating heat exchanger 8b, a first two-way valve NV1, and a second two. Way valve NV
2. It is composed of a bypass BP.

The heat storage tank STR comprises a heat storage material 9, a heat storage heat exchanger 8a, and a heat radiation heat exchanger 8b.

The pump unit PU comprises a refrigerant tank 11, a refrigerant transfer pump PM, and a second four-way valve 3b. The indoor units 13a, 13b are used side exchangers 14a, 1b.
4b and the indoor flow valves 15a and 15b.

In the above construction, the heat source side refrigeration cycle includes the compressor 2, the first four-way valve 3a, and the heat source side heat exchanger 4.
And the first expansion valve 5a and the first auxiliary heat exchanger 7a of the refrigerant-to-refrigerant heat exchanger HEX including the first auxiliary heat exchanger 7a and the second auxiliary heat exchanger 7b are sequentially connected in a ring shape, And second
Expansion valve 5b, heat storage heat exchanger 8a, and heat radiation heat exchanger 8
b is connected in series with a heat storage heat exchanger 8a composed of a heat storage material 9, and the first expansion valve 5a and the first auxiliary heat exchanger 7a of the refrigerant-refrigerant heat exchanger HEX are connected in series. Connected in parallel to the parts.

The refrigeration cycle on the use side is the refrigerant transfer pump P.
M, a second four-way valve 3b, and a pump unit PU in which the refrigerant tank 11 is sequentially connected in a ring shape, and the indoor flow valves 15a, 15
b and a plurality of indoor units 13a and 13b each comprising a use-side heat exchanger 14a and 14b, and the second auxiliary heat exchanger 7
b is connected in series with the first flow valve 5a, whereas the heat radiation heat exchanger 8b is connected in series with the second flow valve RV2 connected in series and is connected in an annular shape. .

A first two-way valve NV1 located between the heat storage heat exchanger 8a and the first auxiliary heat exchanger 7a and one end of the heat storage heat exchanger 8a and the first two-way valve NV1 are connected. A bypass BP having the other end located between the first four-way valve 3a and the heat source side heat exchanger 4 and a second two-way valve NV2 provided in the middle of the bypass BP are provided.

Further, a cooling mode detecting means 18 for detecting the cooling operation mode using the second auxiliary heat exchanger 7b, and a heat storage material for detecting the temperature TW of the heat storage material 9 (for example, water). The pressure P between the temperature detection means 19 and the suction part or the discharge part of the compressor 2 (in the present embodiment, the suction pressure P of the compressor 2).
And a heat storage utilization determining means for determining that the compressor 2 is in an overloaded state and determining that the heat storage heat exchanger 8a can act as a condenser. 21, the second expansion valve 5b and the first two-way valve NV1
And a first control device CN1 including a heat storage utilization drive means 22 for driving the second two-way valve NV2.

The pressure sensor PS is shown as a specific example of the compressor suction pressure detection means 20 for detecting the suction portion pressure P of the compressor 2. The thermistor SM is
It is shown as a specific example of the heat storage material temperature detection means 19 for detecting the temperature TW of the water 9 which is the heat storage material.

As in the case of the conventional example, the first STR circuit and the refrigerant-refrigerant heat exchanger HEX are set so that the heat storage tank STR and the first expansion valve 5a communicate with each other in the heat source side refrigeration cycle.
Is defined as a first HEX circuit, and a setting for communicating the refrigerant-refrigerant heat exchanger HEX with the usage-side heat exchangers 14a, 14b in the usage-side refrigeration cycle is defined as a second HEX circuit. The setting for connecting the circuit, the refrigerant-to-refrigerant heat exchanger HEX, the heat storage tank HEX, and the use side heat exchangers 14a and 14b is defined as a second (HEX + STR) circuit.

Next, the operation of the structure of this embodiment will be described. However, except for the operation of the first control device CN1,
Since the operation is the same as that of the conventional example, the description of the operation of each operation pattern is omitted. The operation of the first control device CN1 different from the conventional example will be described with reference to the flowchart of FIG.

In STEP 1, the cooling mode detecting means 18 causes the cooling operation mode using the second auxiliary heat exchanger 7b.
(That is, the heat source side refrigeration cycle is the first HEX circuit,
It is detected that the use side refrigeration cycle is performing the cooling operation in the second HEX circuit), the process proceeds to STEP2, and otherwise the routine is exited from the routine.

In STEP 2, the heat storage material temperature detecting means 19 detects the water temperature TW of the water 9 as the heat storage material, and STE
Move to P3.

At STEP 3, the suction pressure P of the compressor 2 is detected by the compressor pressure detecting means 20, and the process proceeds to STEP 4.

In STEP 4, the heat storage utilization determining means 20 determines that the water temperature TW is equal to or lower than a first predetermined temperature T1 (for example, TW ≦ 20 ° C.) and the suction pressure P exceeds a predetermined first predetermined pressure P1. (For example, P> 0.65M
If it is Pa), it is determined that the heat storage heat exchanger 8a acts as a condenser using water 9 which is a heat storage material as a heat source, and STEP
Go to 5, otherwise exit the routine.

In STEP 5, the second two-way valve NV2 and the second expansion valve 5b are opened and the first two-way valve NV1 is closed in order to operate the heat storage heat exchanger 8a as a condenser, and ST
Move to EP6. The high temperature gas refrigerant that has exited the compressor 2 by this circuit flows to the outdoor heat exchanger 4 and the bypass BP. Then, by operating both the outdoor heat exchanger 4 and the heat storage heat exchanger 8a as condensers, the heat radiation amount of the condenser as a whole increases and the heat storage heat exchanger 8a becomes a water-cooled condenser. Since the heat transfer rate of is larger than that of the air-cooled condenser, the heat dissipation capacity can be expected to be even larger.

Therefore, since the abnormal increase in the pressure P of the compressor 2 can be suppressed promptly, the reliability of the compressor 2 can be secured, and the upper limit water temperature TW required for the normal cooling operation is 7
Since the water temperature TW of the heat storage tank STR can be used up to 20 ° C. up to 0 ° C., the cold heat of the heat storage tank STR can be effectively used.

In STEP 6, the heat storage utilization determining means 21 causes the water temperature TW to exceed the first predetermined temperature T1 (for example, TW).
> 20 ° C.) or the suction pressure P is equal to or lower than a second predetermined pressure P2 (for example, P ≦ 0.60 MPa),
It is determined that it is not necessary to operate the heat storage heat exchanger 8a as a condenser, and the process proceeds to STEP7.
Return to the head of P5.

In STEP 7, the heat source side refrigeration cycle is returned to the first HEX circuit and the cooling operation is continued.

In this way, STEP1 to STEP7
By repeating this routine during the operation of the cooling and heating device, both the outdoor heat exchanger 4 and the heat storage heat exchanger 8a act as condensers, so that the amount of heat radiated in the condenser increases and the water cooling Since the heat transfer coefficient of the heat storage heat exchanger 8a, which serves as a condenser, is larger than that of the air-cooled condenser, the heat dissipation ability can be expected to be even larger. Therefore, when the suction pressure P of the compressor 2 is abnormally increased, the heat storage heat exchanger 8a is caused to act as a water-cooled condenser, so that the abnormal increase of the pressure P of the compressor 2 can be promptly suppressed. Therefore, there is an effect that the reliability of the compressor 2 can be secured and the cold heat of the heat storage tank STR can be effectively used.

As described above, in this embodiment, in the heat storage type air conditioner, the first two-way valve NV1 located between the heat storage heat exchanger 8a and the first auxiliary heat exchanger 7a and one end of the heat storage air conditioner are stored. The other end between the first heat exchanger 8a and the first two-way valve NV1
A bypass BP located between the four-way valve 3a and the heat source side heat exchanger 4, and a second two-way valve NV2 provided in the middle of the bypass BP.
It has.

When the cooling mode detecting means 18 detects that the cooling operation is in the cycle using the second auxiliary heat exchanger 7b, the heat storage material temperature detecting means 19 determines the temperature TW of the heat storage material 9. Compressor pressure detection means 2
If the suction pressure P of the compressor 2 is detected by 0 and the suction pressure P of the compressor 2 exceeds the predetermined first predetermined pressure P1 by the heat storage utilization judging means 21, the pressure P of the compressor 2 is overloaded. If the temperature TW of the heat storage material 9 is equal to or lower than a first predetermined temperature T1 determined in advance, it is determined that the heat storage heat exchanger 8a can act as a condenser,
The heat storage utilization drive means 22 opens the second expansion valve 5b and the second two-way valve NV2, and closes the first two-way valve NV1.

By the above operation, the outdoor heat exchanger 4
By operating both heat exchangers for heat storage and heat exchanger 8a for heat storage as condensers, the amount of heat radiated in the condenser is increased, and the heat passage rate of heat exchanger 8a for heat storage, which is a water-cooled condenser, is an air-cooled condenser. It is expected to have a larger heat dissipation capacity because it is larger than Therefore, when the suction pressure P of the compressor 2 is abnormally increased, the heat storage heat exchanger 8a is caused to act as a water-cooled condenser, so that the abnormal increase of the pressure P of the compressor 2 can be promptly suppressed. Therefore, there is an effect that the reliability of the compressor 2 can be secured and the cold heat of the heat storage tank STR can be effectively used.

In the present embodiment, the suction pressure P of the compressor 2 is used as the detection when the compressor 2 is overloaded. However, in the overload state, the suction pressure P of the compressor 2 is increased according to the rise of the suction pressure P. Since the discharge pressure also rises, the discharge pressure (however, the first predetermined pressure P1 = 2.3 MPa, the second predetermined pressure P
It is needless to say that the same effect as that of the present embodiment can be obtained by using (2 = 1.8 MPa).

[0059]

As described above, the heat storage type air conditioner of the present invention is a heat storage type air conditioner comprising a heat source side refrigeration cycle and a use side refrigeration cycle through a heat storage tank. And a first auxiliary heat exchanger, a first two-way valve, one end between the heat storage heat exchanger and the first two-way valve, the other end between the first four-way valve and the heat source side heat exchange A bypass located between the air conditioners and a second two-way valve provided in the middle of the bypass, and a cooling mode detection means for detecting the cooling operation mode using the second auxiliary heat exchanger. , A heat storage material temperature detecting means for detecting the temperature of the heat storage material, a compressor pressure detecting means for detecting the pressure of the suction part or the discharge part of the compressor, and determining that the pressure of the compressor is overloaded, Further, a heat storage utilization judging means for judging that the heat storage heat exchanger can act as a condenser. When, in which a first control device that is composed of a heat storage utilizing driving means for driving the second expansion valve and the first two-way valve the second two-way valve.

Then, when the cooling mode detecting means detects that the cooling operation is in a cycle using the second auxiliary heat exchanger, the heat storage material temperature detecting means detects the temperature of the heat storage material. Then, the pressure of the suction part or the discharge part of the compressor is detected by the compressor pressure detection means, and the pressure of the suction part or the discharge part of the compressor is set to a first predetermined pressure by the heat storage utilization determination means. If it exceeds, it is determined that the pressure of the compressor is overloaded, and if the temperature of the heat storage material is equal to or lower than the first predetermined temperature, the heat storage heat exchanger acts as a condenser. When it is determined that it is possible, the heat storage utilization drive means opens the second expansion valve and the second two-way valve and closes the first two-way valve.

By the above operation, when the discharge or suction pressure of the compressor rises abnormally during the cooling operation, the heat exchanger for heat storage acts as a water-cooled condenser to raise the pressure of the compressor abnormally. Since it is possible to quickly suppress the above, it is possible to ensure the reliability of the compressor and to effectively utilize the cold heat of the heat storage tank.

[Brief description of the drawings]

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

FIG. 2 is an operation flowchart of the first control device of the same embodiment.

FIG. 3 is a refrigeration system 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 Heat source side heat exchanger 5a First expansion valve 5b Second expansion valve 7a First auxiliary heat exchanger 7b Second auxiliary heat exchanger 8a Heat storage heat exchanger 8b Radiation heat exchanger 9 Heat storage material 11 Refrigerant tank 13a, 13b Indoor unit 14a, 14b Use side heat exchanger 15a, 15b Indoor flow valve 18 Cooling mode detection means 19 Heat storage material temperature detection means 20 Compressor pressure detection means 21 Heat storage utilization determination means 22 Heat storage utilization drive means 23 First two-way valve drive means BP Bypass PU Pump unit STR Heat storage tank HEX Refrigerant-refrigerant heat exchanger PM Refrigerant transfer pump RV1 First flow valve RV2 Second flow valve NV1 1st 2nd One-way valve NV2 Second two-way valve CN1 First control device

Claims (1)

[Claims] 1. A refrigerant-refrigerant heat exchanger comprising a compressor, a first four-way valve, a heat source side heat exchanger, a first expansion valve, a first auxiliary heat exchanger and a second auxiliary heat exchanger. And the first auxiliary heat exchanger are sequentially connected in an annular shape, and the second expansion valve and the heat storage heat exchanger, the heat radiation heat exchanger, and the heat storage heat exchanger of the heat storage tank are connected in series. A heat source side refrigeration cycle in which the connected ones are connected in parallel to a series connection portion of the first expansion valve and the first auxiliary heat exchanger, a refrigerant transfer pump, a second four-way valve, and a refrigerant tank are sequentially arranged. The pump unit connected in an annular shape, a plurality of indoor units including an indoor flow valve and a use-side heat exchanger, and the second auxiliary heat exchanger and the first flow valve connected in series to the heat radiation unit. The heat exchanger and the second flow valve are connected in series and are connected in parallel. And a first two-way valve located between the heat storage heat exchanger and the first auxiliary heat exchanger, and one end of the heat storage heat exchanger and the first two-way valve. And a second two-way valve having the other end between the first four-way valve and the heat source side heat exchanger, and a second two-way valve in the middle of the bypass, and using the second auxiliary heat exchanger. Cooling mode detection means for detecting that it is in the cooling operation mode, heat storage material temperature detection means for detecting the temperature of the heat storage material, and compression for detecting the pressure of the suction part or the discharge part of the compressor. Machine pressure detection means, heat storage utilization determination means for determining that the pressure of the compressor is overloaded, and for determining that the heat storage heat exchanger can act as a condenser, and the second expansion valve And a heat storage utilization drive means for driving the first two-way valve and the second two-way valve. Is formed, when it is detected by the cooling mode detection means that the cooling operation in the cycle using the second auxiliary heat exchanger, the temperature of the heat storage material is detected by the heat storage material temperature detection means, The pressure of the suction part or the discharge part of the compressor is detected by the compressor pressure detection means, and the pressure of the suction part or the discharge part of the compressor exceeds the predetermined first predetermined pressure by the heat storage utilization determination means. If so, it is determined that the pressure of the compressor is overloaded, and if the temperature of the heat storage material is equal to or lower than a predetermined first predetermined temperature, the heat storage heat exchanger can act as a condenser. A heat storage type air conditioner having a first control device that opens the second expansion valve and the second two-way valve and closes the first two-way valve by the heat storage utilization drive means.