JPH05180519A - Heat storage type refrigeration cycle device - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a heat storage type refrigeration cycle device which is inexpensive, energy saving, and is less likely to cause troubles such as having to stop the cooling operation. [Composition] Compressor, heat source side heat exchanger, first expansion device,
And a refrigeration cycle formed by sequentially connecting the use side heat exchangers, a heat source side heat exchanger bypass path connecting the inlet side and the outlet side of the heat source side heat exchanger, and a heat storage heat exchanger. Between the suction side of the compressor and the outlet side of the heat source side heat exchanger, a bypass path for heat storage, between the outlet side of the heat source side heat exchanger and the inlet side of the heat storage side heat exchanger A second throttle device provided, a second bypass passage for the throttle device connecting the inlet side and the outlet side of the second throttle device, the refrigerant supplied to the heat storage heat exchanger, and the heat A heat storage tank that accommodates the heat storage medium to be exchanged therein, and a heat storage utilization bypass path that connects the refrigerant outlet side of the heat storage heat exchanger and the inlet side of the first expansion device are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat storage type refrigeration cycle device having a heat storage tank.

[0002]

2. Description of the Related Art A conventional embodiment will be described below. That is, FIG. 12 is a cycle explanatory view showing a conventional heat storage type refrigerating apparatus disclosed in, for example, Japanese Patent Laid-Open No. 63-116055, in which 1 is a compressor and 2 is a heat source side heat exchanger. Reference numeral 3 is a first expansion device, 4 is a use side heat exchanger such as an indoor unit of an air conditioner, 6 is a heat storage tank, and a heat storage medium 7 and a heat exchanger 9 are housed inside. The heat exchanger 9 has a heat storage heat exchanger 92 and a heat storage utilization heat exchanger 91. Reference numeral 10 is a first heat storage bypass passage, 10a and 10b are opening / closing devices for the first heat storage bypass passage, 11 is a second expansion device, and
3 is a bypass path for heat storage use, 13a and 13b are switchgear for bypass path for heat storage use, 15 is a refrigerant circulation pump,
Reference numeral 16 is a low pressure side gas-liquid separator, 17 is a high pressure side liquid reservoir, 18 is a second heat storage bypass passage, and 18a and 18b are opening / closing devices for the second heat storage bypass passage.

Next, the operation will be described. The heat storage operation, that is, in order to store low-temperature heat in the heat storage tank 6 by freezing the water as the heat storage medium 7, the switchgear 10b, 1
3a and 18a are closed, and switchgear 10a, 13b and 18b
When the compressor 1 and the refrigerant circulation pump 15 are operated, the high-temperature high-pressure gas refrigerant from the compressor 1 dissipates heat in the heat source side heat exchanger 2, and itself condenses and liquefies to use the liquid reservoir 17 and heat storage. After passing through the bypass passage 13, the second expansion device 11 adiabatically expands to form a low-temperature liquid-gas two-phase fluid and enters the low-pressure side gas-liquid separation device 16. Here, only the low temperature liquid is the refrigerant circulation pump 1
At 5 the heat storage heat exchanger 92 is passed through the second heat storage bypass passage 18, heat is taken from the heat storage medium 7, and the heat is evaporated into gas to return to the low pressure side gas-liquid separation device 16 together with the aforementioned gas. Return to compressor 1.

The cooling operation is a method of radiating the heat absorbed by the indoor heat exchanger 4 on the utilization side, and there are three kinds of operation methods. The first is a method in which all the heat is discharged to the heat storage medium, and since all the condensing load is covered by the cool storage heat, it will be hereinafter referred to as the cool storage condensation cooling operation. This operation is performed by the switchgear 10b, 18
When b is closed, the opening / closing devices 10a and 18a are opened, the compressor 1 is stopped, and only the refrigerant circulation pump 15 is operated, the low-temperature liquid refrigerant transfers the first expansion device 3 to the utilization side heat exchanger 4. Be sent through. Here, heat is taken from the surroundings to cool the room,
It is vaporized and gasified, and is sent to the heat storage heat exchanger 92. Here, the gas is cooled by the low temperature heat storage medium 7, and condenses itself into a low temperature liquid and returns to the low pressure side gas-liquid separation device 16.

The second is a system in which heat is released to both the atmosphere and the heat storage medium, and the liquid refrigerant condensed in the heat source side heat exchanger 2 is further cooled by the cold storage heat. I will call it. This operation is performed by the switchgear 10a, 13
When b and 18b are closed, switchgear 10b, 13a and 18a are opened, and compressor 1 and refrigerant circulation pump 15 are operated, the high temperature and high pressure gas refrigerant from compressor 1 radiates heat in heat source side heat exchanger 2 and itself. Is condensed and liquefied, and enters the heat storage utilization heat exchanger 91 through the liquid reservoir 17. Here, the liquid refrigerant is further cooled by the low temperature heat storage medium 7, and becomes a supercooled liquid,
The expansion device 11 adiabatically expands to form a low-temperature liquid-gas two-phase fluid and enters the low-pressure side machine liquid separation device 16. Here, only the low temperature liquid is sent to the utilization side heat exchanger 4 via the first expansion device 3 by the refrigerant circulation pump 15. Here, heat is taken from the surroundings to be cooled, and it is evaporated and gasified, and returns to the low pressure side gas-liquid separation device 16 via the first heat storage bypass path 10,
Return to the compressor with the previously mentioned gas.

The third is a method of radiating heat only to the atmosphere, which is called a general cooling / refrigeration cycle operation because it is an operation unrelated to heat storage. This operation is performed by the switchgear 10a, 13
When a, 18b are closed, switchgear 10b, 13b, 18b is opened and the compressor 1 and the refrigerant circulation pump 15 are operated, the compressor 1, the heat source side heat exchanger 2, the liquid reservoir 17, and the bypass path 13 for heat storage use. , The second expansion device 11, and the low-pressure side gas-liquid separation device 16 operate in the same manner as in the heat storage operation, and the refrigerant circulation pump 15, the first expansion device 3, the usage-side heat exchanger 4, and the first The heat storage bypass passage 10 and the low-pressure side gas-liquid separation device 16 operate in the same manner as during the liquid subcooling cooling operation.

Regarding the cooling capacity of this system, the capacity during liquid subcooling / cooling operation is larger than the capacity during general cooling / refrigeration cycle operation by the amount of heat that has been supercooled. Therefore, the capacity of the equipment is determined by the performance during the liquid subcooling cooling operation, and the general operation of the system is to perform heat storage operation at night, and when the load is small, cool it by the cool storage condensation cooling operation to reduce the load. When it is large, cooling is performed by liquid subcooling operation, and when heat storage is lost, cooling is performed by general cooling / refrigeration cycle operation.

[0008]

Since the conventional heat storage type refrigeration cycle device is constructed as described above, the refrigerant circulation pump 15 must be operated in all operation modes, and the maximum refrigeration cycle is required. There is a problem in that the amount of refrigerant circulation sufficient to cover the capacity must be secured, which not only goes against energy saving, but also when the refrigerant circulation pump 15 has a problem, the cooling must be stopped.

The present invention has been made in order to solve the above problems, and obtains a heat storage type refrigeration cycle apparatus which is inexpensive, energy saving, and in which troubles such as the necessity of stopping the cooling operation are less likely to occur. The purpose is to

[0010]

A heat storage type refrigeration cycle device according to the present invention is a refrigeration device formed by sequentially connecting a compressor, a heat source side heat exchanger, a first expansion device and a utilization side heat exchanger. A heat source side heat exchanger bypass path connecting the cycle, the inlet side and the outlet side of the heat source side heat exchanger, and a heat storage heat exchanger, the suction side of the compressor and the heat source side heat exchanger And a second expansion device provided between the outlet side of the heat source side heat exchanger and the inlet side of the heat storage heat exchanger. A second bypass passage for the expansion device that connects the inlet side and the outlet side of the expansion device, a heat storage tank that stores therein a heat storage medium for exchanging heat with the refrigerant supplied to the heat storage heat exchanger, Heat storage for connecting the outlet side of the heat storage heat exchanger and the inlet side of the first expansion device A bypass path for use, a first temperature detecting device for detecting the temperature of the heat source medium, and a second temperature detecting device for detecting the temperature of the heat storage medium are provided, and during the heat storage operation, the compressor to the heat source side heat exchanger. A heat storage circuit that reaches the compressor via the second expansion device and the heat storage heat exchanger, a cold path from the compressor to the heat source side heat exchanger bypass path, and the second expansion Device bypass,
The heat storage heat exchanger, the heat storage use bypass passage, the first expansion device, and the cold storage condensing circuit reaching the compressor via the use side heat exchanger, and the compressor during liquid subcooling operation. From the heat source side heat exchanger, the second expansion device bypass passage, the heat storage heat exchanger, the heat storage utilization bypass passage, the first expansion device, and the utilization side heat exchanger. During the liquid subcooling circuit to the compressor and the general cooling operation, the cooling circuit that forms the refrigeration cycle is configured, and based on the temperature detected by the first and second temperature detection devices, the liquid subcooling operation and cold storage condensation The operation mode setting means for selecting the operation and the general cooling operation is provided.

When the temperature detected by the first temperature detecting device is lower than the temperature of the control heat source medium and the temperature detected by the second temperature detecting device is lower than the temperature of the second heat storage medium for control, the cold storage condensation operation is performed. The temperature detected by the first temperature detection device is higher than the temperature of the control heat source medium, and
When the temperature detected by the temperature detecting device is lower than the first control heat storage medium temperature set higher than the second control heat storage medium temperature, operation mode switching means for selecting the liquid supercooling operation is provided. is there.

Further, when the temperature difference between the temperature detected by the first temperature detecting device and the temperature detected by the second temperature detecting device is equal to or more than the reference temperature difference for control, operation mode switching means for selecting the liquid subcooling operation. Is provided.

Further, the temperature of the second control heat storage medium for selecting the cold storage condensing operation is set lower than the temperature of the first control heat storage medium for selecting the liquid subcooling operation, and the second heat storage medium temperature for the control is set during the cold storage condensing operation.
Provided with operation mode switching means for switching to the liquid subcooling operation when the temperature detected by the temperature detecting device rises to a temperature range not lower than the second control heat storage medium temperature and not higher than the first control heat storage medium temperature. Is.

Further, during the cold storage condensing operation, the temperature detected by the second temperature detecting device rises above the second control heat storage medium temperature, and the control reference temperature is higher than the temperature detected by the first temperature detecting device. When the difference is equal to or more than the difference, operation mode switching means for switching to the liquid subcooling operation is provided.

[0015]

The refrigerant circulation of the refrigeration cycle in this invention is
In all of the heat storage operation, the cold storage condensation operation, the liquid supercooling operation, and the general cooling operation, the refrigerant circulation pump is not used and only the compressor is used. Further, during the cold storage condensation operation, even though the compressor operates, a high compression ratio of low C, O,
P (Coefficient of perfomanc)
e: Operate according to the coefficient of performance. Further, the operation mode setting means for selecting the liquid supercooling operation, the cold storage condensation operation and the general cooling operation is automatically operated based on the heat source medium temperature and the heat storage medium temperature detected by the first and second temperature detection devices. Since the mode is switched, the operation for effectively utilizing the heat storage medium is performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below. In the drawings, the same reference numerals indicate the same or corresponding parts.

FIG. 1 is an explanatory view showing a cycle of the heat storage type refrigerating apparatus of the present invention. In the figure, 1 is a compressor, 2 is a heat source side heat exchanger, 3 is a first expansion device, 4 Is a use side heat exchanger such as an indoor unit of an air conditioner, and 5 is an accumulator, which is sequentially connected to 1 to 4 to form a refrigeration cycle. 6 is a heat storage tank that accommodates the heat storage medium 7 therein, 8 is a heat storage medium circulation pump that circulates the heat storage medium between the heat storage tank 6 and the heat storage heat exchanger 9, and 10 is a heat storage bypass path, It has a heat exchanger 9 for heat storage, and connects the suction side of the compressor 1 and the outlet side of the heat source side heat exchanger 2. 10
a, 10b, 10c are switchgear for bypass path for heat storage,
Reference numeral 11 denotes the outlet side of the heat source side heat exchanger 2 and the heat storage heat exchanger 9
The second throttle device provided between the inlet side of the
Second connecting the inlet side and the outlet side of the second expansion device 11
The bypass passage for expansion device, 12a is an opening / closing device for the bypass passage for the second expansion device, and 13 has one end between the refrigerant outlet side of the heat storage heat exchanger 9 and the opening / closing device 10b, and the other end. A bypass path for heat storage use connected between the switchgear 10c and the inlet side of the first expansion device 3, 13a is a switchgear for the bypass path for heat storage use, and 14 is an inlet of the heat source side heat exchanger 2. The heat source side heat exchanger bypass passages connecting the side and the outlet side, and 14a and 14b are switch devices for the heat source side heat exchanger bypass passage.

Further, 21 is a first temperature detecting device for detecting the temperature of the heat source medium flowing into the heat source side heat exchanger 2, and 22 is a second temperature detecting device for detecting the temperature of the heat storage medium 7 flowing into the heat storage heat exchanger. The temperature detection device 23 is an operation mode setting means for automatically selecting various cooling operation modes described later based on the temperatures detected by the first and second temperature detection devices 21 and 22.

Next, the operation will be described. FIG. 2 is a circuit diagram showing the operation during heat storage operation, which is mainly nighttime operation, in which the switchgear 10c, 12a, 13a, 14a is closed, the switchgear 10a, 10b, 14b is opened, and the compressor 1
When the heat storage medium circulation pump 8 is operated, the compressor 1
The higher temperature high pressure gas refrigerant is radiated by the heat source side heat exchanger 2,
It condenses and liquefies itself, adiabatically expands in the second expansion device 11 to become a low temperature liquid gas two-phase fluid, and enters the heat storage heat exchanger 9,
Heat is taken from the heat storage medium 7 sent by the heat storage medium circulation pump 8, and the heat storage medium 7 itself evaporates into gas, and the accumulator 5
After that, it returns to the compressor 1.

By this operation, low temperature heat is stored by freezing the water in the heat storage medium 7. In this embodiment, a heat storage medium circulation pump is used because a forced convection type heat storage heat exchanger is used, but the efficiency is higher than that of a commonly used natural convection type pump, and This method is adopted because it can be expected to reduce the compressor power more than the addition.

FIG. 3, FIG. 5 and FIG. 7 are operation diagrams of the cooling operation, and FIG. 3 shows a circuit diagram during the cold storage condensation cooling operation. In this case, the switchgear 10b, 10c, 12a, 14
When b is closed, the switchgear 10a, 13a, 14a is opened, and the compressor 1 and the heat storage medium circulation pump 8 are operated, the high-temperature high-pressure gas refrigerant from the compressor 1 passes through the heat source side heat exchanger bypass passage 14, the second passage. After entering the heat storage heat exchanger 9 via the expansion device bypass passage 12 and being cooled by the heat storage medium 7 sent by the heat storage medium circulation pump 8, the liquid itself condenses into liquid and adiabatically expands in the first expansion device 3. It becomes a low-temperature liquid gas two-phase fluid and enters the use side heat exchanger 4, where it takes heat from the surroundings and is cooled, and itself evaporates and gasifies, and returns to the compressor 1 via the accumulator 5.

When the operation at this time is shown on the Mollier diagram,
As shown in FIG. 4, the operation is performed at a low compression ratio with the condensing pressure kept low, the compressor input enthalpy (Δid) is extremely small, and the amount of condensation is almost the same as the evaporation enthalpy (Δie) for cooling. Only the enthalpy (Δic) needs to be consumed from the heat storage medium. The English symbols in the figure show the state on the diagram of the position shown in FIG.

FIG. 5 shows a circuit diagram during the liquid subcooling operation.
In this case, when the switchgear 10b, 10c, 14a is closed, the switchgear 10a, 12a, 13a, 14b is opened, and the compressor 1 and the heat storage medium circulation pump 8 are operated, the high-temperature high-pressure gas refrigerant from the compressor 1 becomes Heat is dissipated in the heat source side heat exchanger 2, and the condensed heat is condensed and liquefied, and then enters the heat storage heat exchanger 9 through the second throttle device bypass passage 12. Here, the liquid refrigerant is further cooled by the heat storage medium 7 sent by the heat storage medium circulation pump 8 and becomes a supercooled liquid which is sent to the first expansion device 3, where it is adiabatically expanded and cooled to a low temperature liquid gas two. It becomes a phase fluid and enters the utilization side heat exchanger 4, where heat is taken from the surroundings to be cooled, and itself evaporates and gasifies, and then returns to the compressor 1 via the accumulator 5. When the operation at this time is shown on the Mollier diagram, as shown in Fig. 6, the operation is expanded laterally by only the supercooling enthalpy, and the compressor input enthalpy (Δid) is at that The enthalpy of vaporization for is increased from (Δi1) to (Δi2).

FIG. 7 shows a circuit diagram during a refrigeration cycle operation of general cooling. In this case, the switchgear 10a, 13a, 1
4a is closed and switchgear 10b, 10c, 12a, 14b
When the compressor 1 is opened, the high-temperature high-pressure gas refrigerant from the compressor 1 dissipates heat in the heat source side exchanger 2, condenses itself into liquid, and passes through the second throttling device bypass passage 12 to the first throttling device 12. It is sent to the device 3, where it adiabatically expands to become a low-temperature liquid-gas two-phase fluid and enters the use side heat exchanger 4, where heat is taken from the surroundings to cool it, and it evaporates and gasifies itself, and the accumulator. It returns to the compressor 1 through 5.

As in the conventional embodiment, the cooling capacity of this system is larger than the capacity in the refrigeration cycle operation of general cooling during the liquid subcooling / cooling operation by the amount of supercooled heat. Therefore, the capacity of the equipment is determined by the performance during the liquid subcooling cooling operation, and the general operation of the system is to perform heat storage operation at night, and when the load is small, cool it by the cool storage condensation cooling operation to reduce the load. When it is large, cooling is performed by the liquid subcooling cooling operation, and when heat storage is lost, or when it is necessary to save the heat storage amount before entering the heat storage utilization operation time period, cooling is performed by the refrigeration cycle operation of general cooling.

Next, a method of selecting the above-mentioned various cooling operation modes by the operation mode setting means 23 will be described with reference to the flow charts shown in FIGS. In FIG. 8, when the cooling operation is started in step 40, the heat source medium temperature T _a detected by the first temperature detecting device 21 is compared with the control heat source medium temperature T _a0 in step 41, and T
_{If a} is lower than T _a0 , it is determined that the cooling load is relatively small, and the routine proceeds to step 42. In step 42,
The heat storage medium temperature T _w detected by the second temperature detection device 22 is compared with the second control heat storage medium temperature T _w2 for determining whether or not the heat storage medium temperature is effective for the cold storage condensation operation,
When T _w is lower than T _w2 , the routine proceeds to step 43, where the cold storage condensation operation is selected. In step 41, the heat source medium temperature T
_{If a} is higher than T _a0 , it is determined that the cooling load is large, and the routine proceeds to step 44. In step 44, the heat storage medium temperature T _w is compared with the first control heat storage medium temperature T _w1 for determining whether or not the heat storage medium temperature is effective for the liquid supercooling operation,
When T _w is lower than T _{w1, the routine} proceeds to step 46, where the liquid supercooling operation is selected. When the heat storage medium temperature T _w is higher than the first and second control heat storage medium temperatures T _w1 and T _w2 in step 42 and step 44, the routine proceeds to step 47 to select the general cooling operation. In the case of general air conditioning, the setting of the control heat source medium temperature T _a0 is approximately 28 to 30 in order to distinguish between midsummer and mid-season.
It becomes about ℃.

9 differs from FIG. 8 in that when the heat source medium temperature Ta is higher than Ta ₀ in step 41, the process proceeds to step 45. In step 45, the temperature difference between the heat source medium temperature T _a and the heat storage medium temperature T _w is greater decides whether or not the compared to the control reference temperature T _b, fluid flow proceeds to step 46 when the temperature difference is large Select supercooling operation. That is, when the heat storage medium temperature T _w increases, the temperature difference from the refrigerant temperature condensed by the heat source medium temperature T _a decreases, the heat exchange amount in the heat storage heat exchanger 9 decreases, and the obtained supercooling amount. However, since it does not become so large, it becomes difficult to obtain the effect of heat storage.

In FIG. 10, the first control heat storage medium temperature T _w1 is set higher than the second control heat storage medium temperature T _w2 , and the heat storage medium temperature T _w rises during the cold storage condensation operation. In this case, the process proceeds from step 42 to step 44. In step 44, when the heat storage medium temperature T _W is lower than the first control heat storage medium temperature T _w1 , the process proceeds to step 46 to perform the liquid subcooling operation. In the case of the cold storage condensation operation, the latent heat of condensation of all the refrigerants needs to be processed by the heat storage heat exchanger 9, and the heat exchange amount also becomes large, so the temperature of the heat storage medium that can be effectively used is limited. .. That is, the region where the condensation temperature when condensed by the heat storage medium is lower than the condensation temperature when condensed by the heat source medium is an effective region from the viewpoint of heat storage utilization. (The capacity of the heat storage heat exchanger 9 can be increased as a method of expanding the effective region of the heat storage medium temperature, but it becomes large and uneconomical.) On the other hand, the heat required in the liquid subcooling operation The exchange amount is a small value because it only cools the refrigerant liquid condensed to the liquid region in the heat source side heat exchanger 2. Therefore, it is possible to effectively use the heat storage medium having a higher temperature than in the cold storage condensation operation.

In FIG. 11, during the cold storage condensation operation,
When the heat storage medium temperature T _w has risen, the routine proceeds from step 42 to step 45. In step 45, if the temperature difference between the heat source medium temperature T _a and the heat storage medium temperature T _w is larger than the control reference temperature difference T _b , the process proceeds to step 46 to select the liquid subcooling operation. In other words, after a certain amount of heat storage is used in the cold storage condensing operation, the heat storage is further utilized in the liquid supercooling operation.

In the above embodiment, the case where the air conditioner is used for air conditioning is described, but it can also be used for other purposes such as freezing and refrigerating.

[0031]

As described above, according to the present invention, the refrigeration cycle formed by sequentially connecting the compressor, the heat source side heat exchanger, the first expansion device, and the utilization side heat exchanger, The heat source side heat exchanger has a bypass path for connecting the inlet side and the outlet side of the heat source side heat exchanger, a heat storage heat exchanger, and connects the suction side of the compressor and the outlet side of the heat source side heat exchanger. A bypass passage for heat storage, a second expansion device provided between the outlet side of the heat source side heat exchanger and the inlet side of the heat storage heat exchanger, and an inlet side of the second expansion device. A second expansion device bypass line connecting the outlet side, a refrigerant supplied to the heat storage heat exchanger, a heat storage tank that accommodates a heat storage medium for heat exchange therein, and the heat storage heat exchanger. A bypass path for heat storage utilization that connects the refrigerant outlet side and the inlet side of the first expansion device At the time of heat storage operation, a heat storage circuit from the compressor to the compressor via the heat source side heat exchanger, the second expansion device, and the heat storage heat exchanger, and at the time of cold storage condensation operation, From the compressor to the heat source side heat exchanger bypass passage, the second expansion device bypass passage, the heat storage heat exchanger, the heat storage utilization bypass passage, the first expansion device, and the utilization side heat exchange. Storage condenser circuit leading to the compressor via a compressor, and during liquid supercooling operation, from the compressor to the heat source side heat exchanger, the second bypass device bypass passage, the heat storage heat exchanger, A bypass circuit for heat storage use, the first expansion device, and a liquid subcooling circuit that reaches the compressor via the use-side heat exchanger, and a cooling circuit that forms the refrigeration cycle during general cooling operation. Since it was configured, compressor Is not necessary to separately provide a coolant circulation pump, device can be inexpensive, high energy saving, and hardly generated system problems such as not necessary to stop the cooling has an effect to be obtained.

Further, a first temperature detecting device for detecting the temperature of the heat source medium and a second temperature detecting device for detecting the temperature of the heat storage medium are provided, and the general cooling operation and the liquid cooling operation are performed based on the temperature of the heat source medium and the temperature of the heat storage medium. Since various cooling operation modes are automatically switched by the operation mode switching means for selecting the supercooling operation and the cold storage condensation operation, the heat storage amount stored in the heat storage medium can be effectively used.

When the heat source medium temperature is higher than the control heat source medium temperature and the heat storage medium temperature is lower than the first control heat storage medium temperature, the liquid supercooling operation is selected and the heat source medium temperature is set to the control heat medium. When the temperature is lower than the temperature and the heat storage medium temperature is lower than the second control heat storage medium temperature which is set lower than the first control heat storage medium temperature, the cold storage condensing operation is selected. The heat storage amount can be used in an effective operation mode, and sufficient air conditioning capacity can be exhibited.

Further, since the liquid subcooling operation is selected when the temperature difference between the heat source medium temperature and the heat storage medium temperature is equal to or more than the control reference temperature difference, the heat storage amount can be reliably stored in a state where the supercooling amount can be obtained. It can be used and energy saving effect can be obtained.

Further, the second control heat storage medium temperature for selecting the cold storage condensing operation is set lower than the first control heat storage medium temperature for selecting the liquid supercooling operation, and the heat storage medium temperature is set to the first temperature during the cold storage condensing operation. When the temperature rises above the control heat storage medium temperature of 2 and below the first control heat storage medium temperature, the liquid supercooling operation is switched to. Therefore, even when the air conditioning load is relatively small, It becomes possible to improve the utilization efficiency of the heat storage amount by the cooling operation.

Further, when the heat storage medium temperature rises above the second control heat storage medium temperature during the cold storage condensing operation and the temperature difference from the heat source medium temperature exceeds the control reference temperature difference, Since the mode is switched to the liquid supercooling operation, the heat storage amount can be effectively used by combining the cold storage condensing operation and the liquid supercooling operation.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a heat storage type refrigeration cycle device according to an embodiment of the present invention.

FIG. 2 is an operation diagram during heat storage operation according to an embodiment of the present invention.

FIG. 3 is an operation diagram during cold storage condensation cooling operation according to an embodiment of the present invention.

FIG. 4 is a Mollier diagram of an operation during the cold storage condensation cooling operation according to the embodiment of the present invention.

FIG. 5 is an operation diagram during liquid subcooling cooling operation according to the embodiment of the present invention.

FIG. 6 is a Mollier diagram of an operation during liquid subcooling cooling operation according to the embodiment of the present invention.

FIG. 7 is an operation diagram during the refrigeration cycle operation of general cooling according to the embodiment of the present invention.

FIG. 8 is a flowchart showing a control state for selecting various cooling operation modes according to an embodiment of the present invention.

FIG. 9 is a flowchart showing a control state for selecting various cooling operation modes according to an embodiment of the present invention.

FIG. 10 is a flowchart showing a control state for selecting various cooling operation modes according to an embodiment of the present invention.

FIG. 11 is a flowchart showing a control state for selecting various cooling operation modes according to an embodiment of the present invention.

FIG. 12 is a cycle diagram of a conventional heat storage type refrigeration cycle apparatus.

[Explanation of symbols]

 1 Compressor 2 Heat Source Side Heat Exchanger 3 First Throttling Device 4 Utilization Side Heat Exchanger 6 Heat Storage Tank 7 Heat Storage Medium 9 Heat Storage Heat Exchanger 10 Heat Storage Bypass Path 11 Second Throttling Device 12 Second Throttling Device Bypass path 13 for heat storage use bypass path 14 bypass path for heat source side heat exchanger 21 first temperature detection device 22 second temperature detection device 23 operation mode setting means

Claims (5)

[Claims] 1. A refrigeration cycle formed by sequentially connecting a compressor, a heat source side heat exchanger, a first expansion device, and a utilization side heat exchanger, and an inlet side and an outlet side of the heat source side heat exchanger. A heat-source-side heat exchanger bypass path that connects with, and a heat-storage-side bypass path that has a heat storage heat exchanger and connects the suction side of the compressor and the outlet side of the heat-source-side heat exchanger, and the heat source side. A second throttle device provided between the outlet side of the heat exchanger and the inlet side of the heat storage heat exchanger, and a second throttle device that connects the inlet side and the outlet side of the second throttle device. A device bypass path, a heat storage tank that accommodates therein a heat storage medium that exchanges heat with the refrigerant supplied to the heat storage heat exchanger, a refrigerant outlet side of the heat storage heat exchanger, and the first heat storage tank. The first path for detecting the heat source medium temperature and the bypass path for utilizing heat storage that connects the inlet side of the expansion device A detection device and a second temperature detection device for detecting the temperature of the heat storage medium, and during heat storage operation, from the compressor to the heat source side heat exchanger, the second expansion device,
And a heat storage circuit leading to the compressor via the heat storage heat exchanger, during the cold storage condensation operation, the compressor to the heat source side heat exchanger bypass passage, the second expansion device bypass passage, the heat storage Heat exchanger, bypass path for heat storage use,
A cold storage condensing circuit that reaches the compressor via the first expansion device and the usage-side heat exchanger, and during the liquid subcooling operation, the compressor, the heat source side heat exchanger, and the second expansion device. Bypass path, the heat storage heat exchanger, the heat storage use bypass path, the first expansion device, and the liquid subcooling circuit to the compressor via the use side heat exchanger, and during general cooling operation Includes a cooling circuit that forms the refrigeration cycle, and is provided with operation mode setting means that selects the liquid subcooling operation, the cold storage condensation operation, and the general cooling operation based on the temperatures detected by the first and second temperature detection devices. Heat storage type refrigeration cycle device characterized by 2. When the temperature detected by the first temperature detection device is lower than the temperature of the control heat source medium and the temperature detected by the second temperature detection device is lower than the temperature of the second control heat storage medium, the cold storage condensation operation is performed. The first control in which the temperature detected by the first temperature detecting device is higher than the temperature of the heat source medium for control and the temperature detected by the second temperature detecting device is higher than the temperature of the second heat storage medium for control. The heat storage refrigeration cycle apparatus according to claim 1, further comprising operation mode switching means for selecting a liquid subcooling operation when the temperature is lower than the heat storage medium temperature for use. 3. A temperature detected by the first temperature detecting device,
The operation mode switching means for selecting the liquid subcooling operation when the temperature difference from the temperature detected by the second temperature detecting device is equal to or more than the reference temperature difference for control is provided. Heat storage type refrigeration cycle device. 4. The second control heat storage medium temperature for selecting the cold storage condensation operation is set lower than the first control heat storage medium temperature for selecting the liquid supercooling operation, and the second temperature detection for the cold storage condensation operation. When the temperature detected by the device rises to a temperature range not lower than the second control heat storage medium temperature and not higher than the first control heat storage medium temperature, operation mode switching means for switching to liquid subcooling operation is provided. The heat storage type refrigeration cycle device according to claim 1. 5. The temperature detected by the second temperature detecting device during the cold storage condensing operation rises above the second heat storage medium temperature for control, and the control reference temperature difference with respect to the temperature detected by the first temperature detecting device. The heat storage refrigeration cycle apparatus according to claim 1, further comprising an operation mode switching means for switching to the liquid subcooling operation in the above case.