JPH0571847A - Refrigerator - Google Patents

Abstract

PURPOSE:To obtain a refrigerator in which power demand is averaged by storing electric power at night and shifting it to a daytime. CONSTITUTION:The refrigerator comprises a refrigerating cycle in which a cooler 8 and a heat accumulator 31 having a heat accumulation material 32 therein are connected in parallel, time control means 46 for time-controlling a heat accumulating operation for accumulating heat in the accumulator 31 in an arbitrary time zone and a heat accumulation cooling operation for cooling in the refrigerator by the accumulated heat, indoor temperature sensor 40, heat accumulating temperature sensing means 56 and operation sensing means 55.

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 refrigerator for keeping the inside of a refrigerator cold by using a heat storage material.

[0002]

2. Description of the Related Art In recent years, a heat storage type refrigerator for cooling the inside of a refrigerator by using a heat storage material has been proposed from the viewpoint of effective utilization of late-night power or leveling of power demand by peak cut.
As shown in Japanese Patent No. 58068, it is considered.

An example of the conventional heat storage type refrigerator described above will be described below with reference to the drawings.

FIG. 6 is a longitudinal sectional view showing the structure of a conventional heat storage type refrigerator, and FIG. 7 is a refrigeration system diagram. Figure 6
In FIG. 7, reference numeral 1 designates a cabinet 2 which is a refrigerating cabinet main body and contains a heat insulating material, a door 3, and a gasket 14 which seals the door 3 and the cabinet 2. The interior is divided into two chambers, an upper freezing chamber 17 and a lower refrigerating chamber 18, by a horizontally arranged intermediate partition wall 16.

A compressor 4 is connected to a three-way solenoid valve 6 via a condenser 5. Further, the first outlet 6a of the three-way solenoid valve 6 is connected to the compressor 4 through a capillary 7, a cooler 8 and an accumulator 13 in this order. In addition, the second outlet 6b of the three-way solenoid valve 6
Is the accumulator 13 through the regenerator capillary 9 and the regenerator 10 having the regenerator material 15 filled therein.
Connected. Further, a closed loop type thermosiphon 12 is provided as a heat transfer path between the cooler 8 and the heat storage device 10, and a solenoid valve 11 for a heat storage device is provided in the middle of the closed loop type thermosiphon 12. Are arranged. The closed loop type thermosiphon 12 is, for example, a gravity type, and a refrigerant is enclosed in the closed loop type pipe.

Reference numeral 19 denotes a cooling fan for cooling the inside of the refrigerator, which is provided in front of the cooler 8 and has a freezer compartment upper outlet 2
0 and cold air can be sent out from the lower freezer outlet 21. A freezing compartment suction port 22 is provided in front of the intermediate partition wall 16 on the freezing compartment side, and a freezing compartment intermediate duct 23 extending from the freezing compartment suction port 22 is horizontally formed.
Further, at the back of the cooler 8, the refrigerating compartment duct 2 extending from the cooling fan 19 to the refrigerating compartment outlet 24 along the back surface of the refrigerator.
5 is provided vertically. The refrigerating compartment outlet 24 can be opened and closed by a damper 26. The intermediate partition wall 1
In the front of the refrigerating compartment side of 6, a refrigerating compartment suction port 27 is provided,
A refrigerating compartment intermediate duct 28 extending from here to the cooler 8 is horizontally formed. A glass tube heater 29 is arranged at the outlet of the refrigerating compartment intermediate duct 28, and the defrosting of the cooler 8 arranged above it is possible.

Regarding the refrigerator configured as described above, FIG.
The operation will be described with reference to FIG.

In the normal cooling operation, the coil of the three-way solenoid valve 6 is not energized, the first outlet 6a is communicated, and the condenser 4 is sequentially passed through the condenser 5, the three-way solenoid valve 6 and the capillary 7 from the cooler. 8, a refrigerant flow path from the cooler 8 to the compressor 4 via the accumulator 13 is formed, and the cooler 8 cools the inside of the refrigerator.

On the other hand, in the heat storage operation, the three-way solenoid valve 6
By energizing the coil of No. 2, the second outlet 6b is made to communicate with each other, the compressor 4 is passed through the condenser 5, the three-way solenoid valve 6 and the capillary 7 to reach the heat storage device 10, and the heat storage device 10 is connected to the accumulator. The heat storage material 1 in the heat storage device 10 is constituted by a refrigerant flow path reaching the compressor 4 via
Cool 5

In the heat storage cooling operation, the heat storage solenoid valve 1 is used.
When 1 is opened, the closed loop type thermosiphon 12 cools the heat storage device 10 to the cooler 8, and the heat is used to cool the inside of the refrigerator.

Then, each operation is controlled by a timer action (not shown). At night (23 o'clock to 7 o'clock on the next day) when power demand is low, the heat storage operation and the normal cooling operation are alternately performed by the timer action to cool the heat storage material 15 sufficiently while keeping the internal temperature at the set temperature. Every 3 hours during the peak daytime power demand (13:00 to 16:00), the constant temperature heat storage cooling operation is performed instead of the normal cooling operation requiring a large amount of power to control the temperature inside the warehouse. keep.

[0012]

However, in the above-mentioned structure, when the room temperature is high such as in the summer, a large amount of heat enters from the cabinet, and when the door is opened and closed, the air having a high room temperature is stored in the refrigerator. Since the temperature of the inside of the refrigerator easily rises due to flowing into the inside, the heat storage cooling operation is frequently performed. On the contrary, when the room temperature is low, such as in winter, the amount of heat entering from the cabinet is small, and even if the door is opened / closed, the degree of temperature rise in the refrigerator is low, so the number of times the heat storage cooling operation is executed is small. As described above, the execution frequency of the heat storage cooling operation within a certain time is affected by the room temperature and the number of times of opening and closing the door, and changes. For this reason, if the inside of the refrigerator can be cooled by the heat storage cooling operation only during a certain period of time, the cooling capacity of the heat storage material will be surplus even at the time when that time period expires, and depending on the room temperature, it will be stored in the heat storage material. There is a possibility that the cooling capacity cannot be fully utilized.

In addition, the ratio of the normal cooling operation at night (from 23:00 to 7:00 the next day) is less affected by the amount of heat entering the cabinet and the door opening / closing at a low room temperature such as in winter as compared to a high room temperature such as summer. However, the heat storage material is designed to have a weight that can store the amount of heat required for the constant time (3 hours) heat storage cooling operation at high room temperature, so that the surplus power is surplus. However, there was a problem that all of the heat could not be stored and the electric power demand was leveled and the electric power could not be effectively used.

The present invention solves the above-mentioned problems. It is possible to shift all the surplus electric power at night regardless of room temperature in the daytime and to utilize the cooling capacity of the heat storage material without waste, so that the electric power demand is leveled. It is intended to provide a refrigerator that can effectively use electric power.

[0015]

In order to solve the above problems, the refrigerator of the present invention has a refrigerating cycle in which a cooler and a heat storage device having a heat storage material are connected in parallel, and the heat storage device stores the heat storage device at any time zone. A heat storage operation for storing heat and a time control means for performing time control of a heat storage cooling operation for cooling the inside of the refrigerator by the stored heat are provided, and the weight of the heat storage material is a predetermined low nighttime power demand at low room temperature. During the time period, the compressor is operated continuously, and the refrigerator is cooled by the cooler to keep the temperature at the set temperature. The heat storage operation is performed for all the time except the normal cooling operation, and the heat storage operation has a sufficient heat storage capacity.

Further, it is provided with a room temperature detecting means for detecting the room temperature and a heat storage temperature detecting means for detecting the temperature of the heat storage material, and the time control means detects the room temperature during the heat storage operation by a signal from the room temperature detecting means, The heat storage cooling time is determined according to the estimated value by estimating the heat storage amount and the daytime load amount, and the heat storage cooling operation is performed so that the heat storage cooling operation time zone includes at least the daytime power demand peak time zone. Then, the heat storage temperature detection means detects that the cooling capacity of the heat storage device is exhausted, thereby ending the heat storage cooling operation.

Further, an operation detecting means for detecting the operation of the compressor and a heat storage temperature detecting means for detecting the temperature of the heat storage material are provided, and the time control means determines the heat storage amount by the compressor operation integrated time during the heat storage operation. Estimated by detecting by the signal from the operation detection means, and further estimated by estimating by estimating the compressor operation rate during the normal cooling operation of the previous day by the signal from the operation detection means Depending on the value, the heat storage cooling operation time zone starts the heat storage cooling operation so that at least the daytime power demand includes the time zone of the peak, and the heat storage temperature detection means deactivates the cooling capacity of the heat storage device. Upon detection, the heat storage cooling operation is ended.

[0018]

With the above-described structure, the present invention can shift all the surplus electric power at night regardless of room temperature during the daytime and level the electric power demand.

Further, the heat storage amount and the daytime load amount are estimated from the room temperature, and the heat storage cooling operation time and start are calculated according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the electric power can be effectively used.

Furthermore, the heat storage amount and the daytime load amount can be accurately estimated for each customer who uses the compressor operation time and operation rate, and the heat storage cooling operation time and start can be calculated according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the electric power can be effectively used.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A refrigerator according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing the structure of a refrigerator in one embodiment of the present invention, FIG. 2 is a refrigeration system diagram in one embodiment of the present invention, and FIG. 3 is in one embodiment of the present invention. FIG. 5 is an electric circuit diagram of a main part, and FIG. 5 is a diagram showing an operating state of one day according to room temperature in one embodiment of the present invention.

In FIG. 1, reference numeral 30 denotes a cool box body, which is composed of a cabinet 2 containing a heat insulating material, a door 3, and a gasket 14 for sealing the door 3 and the cabinet 2. The inside thereof is partitioned into two chambers, an upper freezing chamber 17 and a lower refrigerating chamber 18, by a horizontally arranged heat insulating partition wall 33.

Reference numeral 57 is a cooling chamber provided in the freezing chamber 17, and the cooler 8 and the cooling fan 19 are provided in the cooling chamber 57.

Inside the adiabatic partition wall 33, there is provided a ventilation passage A37 for connecting the freezing compartment suction port 36 and the cooling chamber 57 by replacing the division wall 38, and a ventilation passage B39 for communicating the refrigeration compartment suction port 35 and the cooling chamber 57. Is forming. Reference numeral 31 is a heat storage unit that is filled in the inside of the air passage B39 with the heat storage material 32, and 56 is a heat storage temperature detection means that detects the temperature of the heat storage material 32 attached to the heat storage unit 31.

Reference numeral 34 denotes an air passage switching means, which is provided on the partition wall 38 on the side of the freezing compartment suction port 36 and the refrigeration compartment suction port 35.
The air passage switching means 34 closes the air passage B39 34
a and 34b for closing the air passage A37.

Reference numeral 26 is a damper for adjusting the discharge air flow rate of the cool air blown to the refrigerating compartment duct 25 by the cooling fan 19 to the refrigerating compartment 18 to control the refrigerating compartment 18 to a preset temperature.

In FIG. 2, reference numeral 4 denotes a compressor, which is connected to a three-way solenoid valve 6 via a capacitor 5. Further, the first outlet 6a of the three-way solenoid valve 6 is connected to the compressor 4 through a capillary 7, a cooler 8 and an accumulator 13 in this order. Further, the second outlet 6b of the three-way solenoid valve 6 is connected to the accumulator 13 through the regenerator capillary 9 and the regenerator 31 filled with the regenerator material 15 in order.

In FIG. 3, only a portion related to the gist of the present invention is shown in the electric circuit diagram, and 46 is a CPU as a time control means, which is operated by a program stored in a storage circuit (not shown) as is well known. The relay circuit 4 outputs the current time, and outputs the signals from the room temperature detecting means 40 and the inside temperature detecting circuit 44.
Energization control of 7, 49, 51, 53 is performed. That is, each relay 47, 49, 51, 53 is energized by applying a high level signal to the base of each transistor 48, 50, 52, 54 connected to each relay 47, 49, 51, 53. To be done.

When the relay 47 is energized, the compressor 4
Will drive. When the relay 49 is energized, the three-way solenoid valve 6 operates to communicate the second outlet 6b, and when the relay 49 is not energized, the first outlet 6a communicates. Relay
When 51 is energized, the cooling fan 19 operates. Relay
When 53 is energized, the air passage switching means 34 closes the air passage A37 (34b), and when the relay 53 is not energized, it closes the air passage B39 (34a).

Further, the internal temperature detection circuit 44 outputs a signal to the time control means 46 when the value detected by the temperature sensor 43 is equal to or higher than the set temperature. Further, the room temperature detecting means 40 is
The room temperature around the refrigerator is A /
The D converter 42 digitizes the output voltage and outputs a signal to the time control means 46. Further, the heat storage temperature detecting means 5
6 outputs a signal to the time control means 46 when the value detected by the temperature sensor 57 is equal to or higher than the set temperature.

FIG. 1 shows the refrigerator constructed as described above.
The operation will be described with reference to FIGS. 2, 3, and 4.

In the normal cooling operation, the inside of the refrigerator is cooled by using the cooler 8 and kept at the set temperature. That is, CPU4
By turning off the relays 51 and 53 by 6, the refrigerant flow passage is on the side communicating with the cooler 8, the cold air passage is the air passage switching means 34b on the side 34b, and the air passage A is maintained in the communication state. When the temperature inside the refrigerator is equal to or higher than the set value, the CPU 46 causes the relays 47 and 4 to output a signal from the temperature detecting circuit 44.
By turning ON 9 and operating the compressor 4 and the cooling fan 19, the inside of the refrigerator is cooled to below the set temperature by the cooler 8. Then, when the temperature inside the refrigerator becomes equal to or lower than the set value, the signal of the temperature detecting circuit 44 inside the refrigerator is turned off, and the CPU 46 releases the relay.
47 and 49 are turned off to stop the circulation of the refrigerant and the cool air. By repeating the above operation, the inside of the refrigerator is cooled to the set temperature.

In the heat storage operation, during a predetermined time period when the power demand at night is low (from 23:00 to 7:00 on the next day), the heat storage material 32 filled in the heat storage unit 31 is supplied with power during a predetermined time period at night. Is stored in place of heat. That is, CP
The relays 51 and 47 are turned on by U46 to hold the refrigerant flow path on the side where the heat storage device 31 communicates, and by operating the compressor 4, the refrigerant is evaporated in the heat storage device 31 and the heat storage material 32 is transferred. Freeze.

The weight of the heat storage material 32 is set based on the low room temperature such as winter. That is, when the compressor is continuously operated during a predetermined time period (from 23:00 to 7:00 of the next day) when the nighttime power demand at low room temperature is low, the heat storage operation is performed for all the time other than the normal cooling operation, and the heat storage operation heat amount is The weight is all that can store heat. This is based on the period when the amount of heat entering from the cabinet 2 and the opening and closing of the door 3 have little influence on the temperature inside the refrigerator, and the heat storage operation heat amount is large. All electric power other than the normal cooling operation in the predetermined time zone can be stored.

In the heat storage cooling operation, the inside of the cold storage is kept cool by utilizing the heat stored in the heat storage unit 31 during the peak daytime power demand. That is, the CPU 46 releases the relay 53.
By turning on, the cold air passage is changed to the air passage switching means 34.
Is on the 34a side and the ventilation passage B is maintained in a communicating state, and when the internal temperature is equal to or higher than the set value, the CPU 46 turns on the relay 49 by the signal from the internal temperature detection circuit 44 to operate the cooling fan 19. As a result, the inside of the refrigerator is cooled to the set temperature or lower by the heat accumulated in the heat accumulator 31. Then, when the temperature inside the refrigerator becomes equal to or lower than the set value, the signal of the temperature detecting circuit 44 inside the oven becomes OF.
When it becomes F, the CPU 46 turns off the relay 49 and stops the circulation of the cool air. By repeating the above operation, the inside of the refrigerator is cooled to the set temperature.

Next, the control method for each operation will be described with reference to FIG. By the time control means 46, the normal cooling operation and the heat storage operation are alternately performed in a predetermined time zone (from 23:00 to 7:00 of the next day) when the nighttime power demand is low. That is, when the temperature inside the refrigerator is equal to or higher than the set value, the inside of the refrigerator is cooled by the normal cooling operation, and when the temperature inside the refrigerator is equal to or lower than the set value, heat is stored in the heat storage operation instead of heat.

However, the time ratio between the normal cooling operation and the heat storage operation at that time changes depending on the room temperature. This is because the amount of heat entering from the cabinet 2 and the refrigerating capacity of the system change depending on the room temperature, and the lower the room temperature, the lower the ratio of normal cooling operation and the larger the amount of heat storage. From this, the room temperature detection means 40 detects the average room temperature in a predetermined time zone when the nighttime power demand is low, and the time control means 46 estimates the heat storage amount.

The time control means 46 also estimates the daytime load amount from the daytime average room temperature detected by the room temperature detection means 40.

From these estimated values, the time control means 46 starts the heat storage cooling operation so that at least the daytime power demand includes the peak time zone (13:00 to 16:00). Then, the heat storage temperature detection means 56 sends a signal to the time control means 46 that the heat storage material 32 has exceeded the set temperature and the cooling capacity of the heat storage device 31 has disappeared, whereby the heat storage cooling operation ends.

For example, as shown in FIG. 5, the heat storage cooling operation time is 3 hours at a room temperature of 30 ° C. and 8 hours at a room temperature of 15 ° C.

Next, a refrigerator according to another embodiment will be described with reference to the drawings. FIG. 4 is an electric circuit diagram of a main part in another embodiment of the present invention, and 55 is an operation detecting means for sending a signal to the CPU 46 when the compressor 4 is operating.

The daytime load amount includes the amount of heat entering from the cabinet 2, the amount of heat entering the door 3 when opening and closing, and the load amount of the stored material. The door opening and closing and the stored material load amount differ depending on the customer who uses the product. .. Since the total load amount and the compressor operating rate during the normal cooling operation are in a proportional relationship, the time detecting means 55 detects the compressor operating rate during the normal cooling operation on the previous day by the time control means 46. , You can guess the exact daytime load.

Further, even in the heat storage amount at night, the operation detecting means 5 calculates the operation accumulated time of the compressor 2 during the heat storage operation.
According to 5, the time control means 46 detects it, so that an accurate heat storage amount can be estimated.

Based on these accurate estimated values, the time control means 46 determines at least the time period (1
The heat storage cooling operation is started so as to include from 3 o'clock to 16 o'clock. Then, the heat storage temperature detection means 56 sends a signal to the time control means 46 that the heat storage material 32 has exceeded the set temperature and the cooling capacity of the heat storage device 31 has disappeared, whereby the heat storage cooling operation ends.

As described above, according to this embodiment, the refrigerating cycle in which the cooler and the heat accumulator having the heat accumulating material inside are connected in parallel, and the heat storage operation for storing heat in the heat accumulator at an arbitrary time zone, And a time control means for performing time control of a heat storage cooling operation for cooling the inside of the refrigerator by the stored heat, and the weight of the heat storage material is such that the compressor is continuously operated in a predetermined time zone when the power demand at night is low at low room temperature. The refrigerator is cooled by a cooler to keep the temperature at the set temperature.The heat storage operation is performed for all time except the normal cooling operation, and the weight of the heat storage operation is set to be the weight that can store all the heat. Since it is equipped with a heat storage temperature detecting means for detecting and a heat storage temperature detecting means for detecting the temperature of the heat storage material, it is possible to shift all the surplus power at night regardless of room temperature during the daytime and level the power demand. Can.

Further, the heat storage amount and the load amount in the daytime are estimated from the room temperature, and the heat storage cooling operation time and start are calculated according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the electric power can be effectively used.

Furthermore, the heat storage amount and the daytime load amount can be accurately estimated for each customer who uses the operation time and operation rate of the compressor, and the heat storage cooling operation time and start can be calculated according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the electric power can be effectively used.

[0049]

As described above, the present invention has a refrigerating cycle in which a cooler and a heat storage device having a heat storage material are connected in parallel, a heat storage operation for storing heat in the heat storage device at any time and a heat storage operation. And a time control means for performing a time control of a heat storage cooling operation for cooling the inside of the refrigerator by the heat, the weight of the heat storage material is a continuous operation of the compressor during a predetermined time period when the power demand at night is low at low room temperature. The refrigerator is cooled by the cooler and kept at the set temperature during the time other than the normal cooling operation.

Further, a room temperature detecting means for detecting room temperature and a heat storage temperature detecting means for detecting the temperature of the heat storage material are provided, and the time control means detects the room temperature during the heat storage operation by a signal from the room temperature detecting means, The heat storage cooling time is determined according to the estimated value by estimating the heat storage amount and the daytime load amount, and the heat storage cooling operation is performed so that the heat storage cooling operation time zone includes at least the daytime power demand peak time zone. Then, the heat storage temperature detection means detects that the cooling capacity of the heat storage device is exhausted, thereby ending the heat storage cooling operation.

Further, an operation detecting means for detecting the operation of the compressor and a heat storage temperature detecting means for detecting the temperature of the heat storage material are provided, and the time control means determines the heat storage amount by the accumulated operation time of the compressor during the heat storage operation. Estimated by detecting by the signal from the operation detection means, and further estimated by estimating by estimating the compressor operation rate during the normal cooling operation of the previous day by the signal from the operation detection means Depending on the value, the heat storage cooling operation time zone starts the heat storage cooling operation so that at least the daytime power demand includes the time zone of the peak, and the heat storage temperature detection means deactivates the cooling capacity of the heat storage device. Since the heat storage cooling operation is terminated by detecting it, all the surplus power at night can be shifted to the daytime regardless of the room temperature, and the power demand can be leveled. The refrigerator.

Further, the heat storage amount and the daytime load amount are estimated from the room temperature, and the heat storage cooling operation time and the start time are determined according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the refrigerator can effectively use electric power.

Further, the heat storage amount and daytime load amount can be accurately estimated for each customer who uses the operation time and operation rate of the compressor, and the heat storage cooling operation time and start can be calculated according to the heat storage amount.
Since the end time can be controlled and the cooling capacity of the heat storage material can be utilized without waste, the refrigerator can effectively use electric power.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of a refrigerator according to an embodiment of the present invention.

FIG. 2 is a refrigeration system diagram of the refrigerator shown in FIG.

FIG. 3 is an electric circuit diagram of a main part of the refrigerator shown in FIG.

FIG. 4 is an electric circuit diagram of a main part of a refrigerator according to another embodiment of the present invention.

[Fig. 5] Fig. 5 is a diagram showing a daily operation state according to the room temperature in Fig. 1.

FIG. 6 is a vertical sectional view showing the structure of a conventional refrigerator.

7 is a refrigeration system diagram of the refrigerator of FIG.

[Explanation of symbols]

 8 cooler 31 heat storage device 32 heat storage material 40 room temperature detection means 46 time control means 55 operation detection means 56 heat storage temperature detection means

Claims (3)

[Claims] 1. A refrigeration cycle in which a cooler and a heat storage device having a heat storage material inside are connected in parallel, a heat storage operation of storing heat in the heat storage device at an arbitrary time zone, and a refrigerator is cooled by the stored heat. The heat storage material is provided with a time control means for performing time control of the heat storage cooling operation, and the weight of the heat storage material is such that the compressor is continuously operated and a refrigerator is cooled by a cooler during a predetermined time period when the power demand at night is low at low room temperature. A refrigerator characterized by performing heat storage operation for the entire time period other than the normal cooling operation of maintaining the set temperature, and making the heat storage operation heat amount sufficient to store heat. 2. A room temperature detecting means for detecting the room temperature and a heat storage temperature detecting means for detecting the temperature of the heat storage material are provided, and the time control means operates the compressor continuously during a predetermined time period when the power demand at night is low and normally cools. Heat is stored by the heat storage operation in all times other than operation, and the room temperature during the heat storage operation is detected by the time control means by the signal from the room temperature detection means, and estimated by estimating the heat storage amount and the daytime load amount. The heat storage cooling time is determined according to the value, the heat storage cooling operation time zone starts the heat storage cooling operation so that at least the daytime power demand includes the time zone of the peak, and the heat storage temperature detection means of the heat storage unit. The refrigerator according to claim 1, wherein the heat storage cooling operation is ended by detecting that the cooling capacity is exhausted. 3. An operation detection means for detecting the operation of the compressor and a heat storage temperature detection means for detecting the temperature of the heat storage material, and the time control means continuously operates the compressor during a predetermined time zone when the power demand at night is low. The heat storage operation stores heat for all times other than the normal cooling operation, and the time control means estimates the heat storage amount by detecting the compressor operation integrated time during the heat storage operation by a signal from the operation detection means. Further, the daytime load is estimated by detecting the compressor operating rate during the normal cooling operation of the previous day by the signal from the operation detecting means, and the heat storage cooling operation time zone is at least the daytime power demand according to the estimated value. The heat storage cooling operation is started so as to include the peak time zone, and the heat storage temperature detection means detects that the cooling capacity of the heat storage device is lost. The heat storage cooling operation is terminated.
Refrigerator described.