JP7215919B2 - cold storage - Google Patents

Description

The technology disclosed herein relates to cold storage.

2. Description of the Related Art Conventionally, there is known a refrigeration storage that detects a refrigerant leak in a refrigeration circuit (see, for example, Patent Document 1). Specifically, the refrigerator described in Patent Literature 1 determines that there is a refrigerant leak when the temperature detected by an evaporation temperature sensor that detects the piping temperature of the evaporator falls below the boiling point of the refrigerant, and shifts to leakage countermeasure control. Patent Document 1 discloses a leak countermeasure control that includes a variable capacity compressor and an outside air temperature sensor that detects the outside air temperature, and continuously operates at a predetermined capacity according to the set temperatures of the outside air temperature and the inside temperature. stated to do.

Japanese Patent Application Laid-Open No. 2006-10126

However, according to the refrigerator described in the above-mentioned Patent Document 1, when refrigerant leakage occurs in the refrigeration circuit, the variable capacity compressor is continuously operated, so the refrigerant leakage accelerates and tends to accumulate outside or inside the refrigerator. There is a problem. If the refrigerant is a flammable refrigerant, it is dangerous if the leaked refrigerant stays in one place.

This specification discloses a technique for suppressing an increase in the internal temperature of the refrigerator and preventing the leaked coolant from accumulating in one place when a coolant leak occurs.

The cooling storage disclosed herein includes a storage main body having an opening, a door for opening and closing the opening, a constant speed compressor with a constant rotation speed, a first condenser and a first evaporator. a refrigerating circuit, a second refrigerating circuit having an inverter compressor with a variable rotation speed, a second condenser and a second evaporator, an internal temperature sensor for detecting internal temperature, and the door being opened A detection unit that detects that the refrigerator has been heated, an ambient temperature sensor that detects the ambient temperature, and a control unit, and the control unit operates the inverter compressor to cool the inside of the refrigerator. a cooling operation in which the inverter compressor is stopped when the internal temperature drops to the lower limit temperature of the cooling temperature range, and the operation of the inverter compressor is restarted when the internal temperature rises to the upper limit temperature of the cooling temperature range; , an auxiliary cooling operation for auxiliary cooling the inside of the refrigerator by operating the constant speed compressor when the temperature inside the refrigerator is higher than the upper limit temperature and the temperature inside the refrigerator has not decreased along a predetermined target line; Then, under the condition that the opening of the door is not detected by the detection unit and the ambient temperature is equal to or lower than a predetermined temperature, the temperature of the first condenser and the ambient temperature are measured at regular intervals. The difference between the temperature and the temperature is within a predetermined range continuously for a predetermined number of times or more, or the difference between the temperature of the second condenser and the ambient temperature is within a predetermined range for a predetermined number of times or more. If it continues, the compressor of the refrigerating circuit for which the difference is within the predetermined range for the predetermined number of times or more is stopped, and the compressor of the other refrigerating circuit is operated.

The inventors of the present application have obtained the following findings as a result of earnest studies.
- When the compressor is not running, the temperature of the condenser does not rise, so the temperature of the condenser is close to the ambient temperature. Therefore, the difference between the temperature of the condenser and the ambient temperature becomes smaller than the lower limit (1K) of a predetermined range (eg, 1 to 3K).
- When the compressor is in operation, the temperature of the condenser rises, so the difference between the temperature of the condenser and the ambient temperature becomes larger than the upper limit (3K) of the predetermined range.
- If the difference between the temperature of the condenser and the ambient temperature is within the predetermined range, there is a high possibility that the compressor is being operated with a refrigerant leak.
For this reason, if the difference between the condenser temperature and the ambient temperature is within a predetermined range for a certain number of times or more in succession (that is, if there is a high possibility that the compressor is being operated with a refrigerant leak), the refrigerant leak will be detected. It is desirable to execute a predetermined process (such as a process to rotate the condenser fan, a process to issue an alarm that a refrigerant leak may have occurred, etc.).
However, if the ambient temperature is high or if the door is opened and closed frequently, the difference between the condenser temperature and the ambient temperature will be outside the specified range as the temperature of the condenser rises even when the refrigerant is leaking ( greater than 3K). Therefore, if the difference between the temperature of the condenser and the ambient temperature is within a predetermined range for more than a predetermined number of times in succession, there is a possibility that the predetermined process will not be executed.
According to the above cooling storage, under the condition that the door is not opened and the ambient temperature is below a predetermined temperature, it is constant that the difference between the temperature of the condenser and the ambient temperature is within a predetermined range. Since the predetermined process is executed when the number of times or more continues, it is possible to prevent the predetermined process from not being executed in the state of refrigerant leakage.
Further, according to the above cooling storage, when the compressor is stopped due to a failure, the difference between the temperature of the condenser and the ambient temperature is outside the predetermined range (for example, less than 1K), so the predetermined process is executed. not. Therefore, unnecessary execution of the predetermined process can be suppressed when the compressor is stopped due to a failure.
According to the above cooling storage, when refrigerant leakage occurs in one of the refrigerating circuits, the compressor of the refrigerating circuit in which the refrigerant leakage has occurred is stopped, and the compressor of the other refrigerating circuit is operated. Stopping the compressor of the refrigeration circuit in which the refrigerant leakage has occurred can reduce the speed of the refrigerant leakage, so that the leaked refrigerant can be prevented from accumulating in one place. Moreover, since the compressor of the other refrigeration circuit in which no refrigerant leakage has occurred is operated, it is possible to suppress an increase in the temperature inside the refrigerator.
Therefore, according to the cooling storage described above, when a refrigerant leak occurs, it is possible to prevent the leaked refrigerant from accumulating in one place while suppressing an increase in the temperature inside the storage.

The control unit may execute a predetermined process regarding refrigerant leakage when the difference is within the predetermined range for the predetermined number of times or more.

According to the cooling storage described above, it is possible to reduce the influence of refrigerant leakage by executing predetermined processing regarding refrigerant leakage.

The predetermined processing may include processing for operating the inverter compressor at a maximum rotation speed when the difference in the first refrigerating circuit is within the predetermined range for a predetermined number of times or more.

According to the cooling storage described above, it is possible to more reliably suppress an increase in temperature inside the storage when refrigerant leakage occurs in the first refrigeration circuit.

The cooling storage disclosed herein includes a storage main body having a first storage chamber and a second storage chamber, a first door for opening and closing an opening of the first storage chamber, and a second storage chamber. A second door for opening and closing the opening of the chamber, a compressor, a condenser, a first evaporator disposed within the first storage chamber, and a second evaporator disposed within the second storage chamber. a refrigeration circuit having a switching valve that selectively switches a path of refrigerant condensed by the condenser to at least one of the first evaporator and the second evaporator; and the first storage chamber. a first chamber temperature sensor that detects the temperature of the first chamber, a first detector that detects that the first door is opened, and a second chamber that detects the temperature in the second chamber A temperature sensor, a second detection section that detects that the second door is opened, an ambient temperature sensor that detects ambient temperature, and a control section, wherein the control section operates the switching valve. A cooling operation for cooling the first storage compartment and the second storage compartment by alternately switching, wherein the internal temperature of the first storage compartment is the lower limit of the cooling temperature range of the first storage compartment. temperature, and when the internal temperature of the second storage chamber drops to the lower limit temperature of the cooling temperature range of the second storage chamber, the compressor is stopped, and then one of the storage chambers When the internal temperature of the storage chamber rises to the upper limit temperature of the cooling temperature range of the storage chamber, the cooling operation is performed to restart the operation of the compressor, and for each storage chamber, it is confirmed that the door of the storage chamber is opened. The switching valve is opened under the conditions that it is not detected by the detection unit, the ambient temperature is equal to or less than a predetermined temperature, and the difference between the temperature of the condenser and the ambient temperature is equal to or greater than a predetermined value. When the increase in the temperature of the storage chamber is equal to or greater than a predetermined value for a predetermined period of time while the refrigerant is being supplied to the evaporator of the storage chamber, predetermined processing regarding refrigerant leakage is performed. do.

2. Description of the Related Art Conventionally, it is known to detect occurrence of refrigerant leakage in a refrigerating circuit in a refrigeration storage (for example, Japanese Unexamined Patent Application Publication No. 2017-219278). Specifically, in the cooling storage described in JP-A-2017-219278, the internal detection temperature Tm is set in advance to a temperature higher than the internal set temperature Ts while operating in the normal cooling mode. When the state exceeding the warning temperature Te continues for a predetermined time, it is determined that there is a possibility that refrigerant leakage has occurred, and control is performed in the leakage warning mode.
By the way, when the ambient temperature is high or when the door is frequently opened and closed, the internal temperature also increases. For this reason, the cooling storage described in JP-A-2017-219278 described above may erroneously determine that there is a possibility that a refrigerant leak has occurred when the ambient temperature is high or when the door is frequently opened and closed. have a nature. In the cooling storage described in Japanese Patent Application Laid-Open No. 2017-219278, when it is erroneously determined that there is a possibility that refrigerant leakage has occurred, control in the leakage alert mode is performed unnecessarily.
The inventor of the present application found that when a refrigerant leak occurs in the refrigeration circuit, the temperature in the storage chamber rises due to insufficient supply of low-temperature refrigerant to the evaporator, and the range of temperature rise in the storage chamber at regular intervals is It was found that the constant value or more continues for more than a certain number of times. For this reason, if the increase in the temperature of the storage room at regular time intervals continues to exceed a certain value for a certain number of times or more, it is necessary to take prescribed actions related to the refrigerant leak (processing to rotate the condenser fan, the possibility that a refrigerant leak has occurred). It is desirable to execute a process to warn that there is a risk, etc.).
However, if the ambient temperature is high, if the door is opened and closed frequently, or if the compressor is stopped due to a malfunction, the temperature inside the storage room will rise, and the temperature rise in the storage room will increase at regular intervals. is equal to or greater than a certain value in succession for a certain number of times. For this reason, there is a possibility that the predetermined process will be executed unnecessarily simply by simply stating that the increase in the temperature of the storage chamber is equal to or greater than a certain value at regular intervals for a certain number of times or more.
Here, normally, even if a refrigerant leak occurs, the temperature of the condenser is somewhat higher than the ambient temperature as long as the compressor is in operation. Therefore, when the temperature detected by the condenser temperature sensor is higher than the ambient temperature detected by the ambient temperature sensor by a predetermined value or more, it can be determined that the compressor is operating.
According to the above cooling storage, for each storage compartment (the first storage compartment and the second storage compartment), the opening of the door of the storage compartment is not detected by the detection unit, and the ambient temperature is the predetermined temperature. or less, and the difference between the temperature of the condenser and the ambient temperature is equal to or greater than a predetermined value, the switching valve is opened and the refrigerant is supplied to the storage chamber of the storage chamber for a certain period of time. If the increase in the internal temperature of the relevant storage compartment is equal to or greater than a certain value in succession for a certain number of times or more, predetermined processing regarding refrigerant leaks will be executed. Unnecessary execution of the predetermined process can be suppressed when the compressor is stopped due to a failure.

In the predetermined process, when the increase width of the inside temperature of the first storage chamber is equal to or greater than a predetermined value for each predetermined time in succession for a predetermined number of times or more, the first storage chamber side of the refrigerating circuit is outputting an alarm indicating that there is a high possibility that a refrigerant leak has occurred in the low-pressure circuit of the second storage chamber, and it is constant that the increase in temperature inside the second storage chamber at regular intervals is equal to or greater than a predetermined value. If it continues for more than the number of times, an alarm is output indicating that there is a high possibility that a refrigerant leak has occurred in the low-pressure circuit on the side of the second storage compartment of the refrigeration circuit, and both storage compartments are at regular intervals. If the increase in temperature inside the refrigerator is equal to or greater than a certain value in succession for a certain number of times or more, an alarm is output to indicate that there is a high possibility that a refrigerant leak has occurred in the high-pressure circuit of the refrigeration circuit. It's okay.

Here, from the compressor to the switching valve is the high-pressure circuit of the refrigeration circuit, from the switching valve to the first evaporator is the low-pressure circuit on the side of the first storage compartment, and from the switching valve to the second evaporator is the second storage compartment. side low-voltage circuit.
According to the above cooling storage, a worker who repairs a refrigerant leak can determine whether the refrigerant is leaking from the low pressure circuit on the side of the first storage compartment, the low pressure circuit on the side of the second storage compartment, or the high pressure circuit of the refrigeration circuit. Since it is possible to know from the alarm whether there is a high possibility that the refrigerant is leaking, it becomes easy to identify the location where the refrigerant leakage is occurring. Therefore, refrigerant leakage can be repaired efficiently.

When there is a high possibility that refrigerant leakage has occurred in the low-pressure circuit, the predetermined processing is performed by switching the switching valve so that the refrigerant does not flow to the low-pressure circuit side where the possibility of refrigerant leakage is high. may include a process of switching.

According to the cooling storage described above, since the switching valve is switched so that the refrigerant does not flow to the low-pressure circuit side where the refrigerant is leaking, the speed at which the refrigerant leaks can be suppressed.

The predetermined process includes a process of operating a condenser fan that cools the condenser, a process of operating an internal fan that circulates the air cooled by the evaporator into the compartment, and a process of defrosting the evaporator. At least one of a process of prohibiting frost operation and a process of alarming refrigerant leakage may be included.

When the condenser fan is operated, in the case of refrigerant leakage outside the refrigerator, the leaked refrigerant can be diffused outside the refrigerator. Therefore, when the refrigerant is a combustible refrigerant, it is possible to reduce the risk of the leaked combustible refrigerant remaining in one place.
Further, when the inside fan is operated, in the case of refrigerant leakage inside the refrigerator, the refrigerant can be gradually diffused outside the refrigerator through a small gap between the door and the storage body. Therefore, when the refrigerant is a flammable refrigerant, it is possible to reduce the risk of the flammable refrigerant leaking out of the refrigerator remaining in one place.
In addition, by prohibiting the defrosting operation, it is possible to suppress adverse effects on the foodstuffs stored in the cold storage. Specifically, since the compressor is generally stopped during the defrosting operation, the internal temperature rises. Normally, the operation of the compressor will resume after that and the temperature inside the refrigerator will drop, so the food will not be adversely affected. Since the temperature does not drop, the temperature inside the refrigerator remains high, which may damage the food inside. If the defrosting operation is prohibited, it is possible to suppress the possibility of damage to the foodstuffs in the refrigerator.
In addition, when a refrigerant leakage alarm is issued, the user can be urged to refrain from opening and closing the door. If the opening and closing of the door is refrained, the temperature inside the refrigerator is less likely to rise, so it is possible to suppress the possibility of damage to the foodstuffs inside the refrigerator. In addition, when a refrigerant leak warning is issued, the user can be encouraged to ventilate the room. Therefore, it is possible to reduce the risk of the flammable refrigerant leaking out of the refrigerator staying inside the refrigerator. In addition, when a refrigerant leak alarm is issued, the user can promptly request service from the manufacturer of the cold storage, thereby suppressing the possibility of damage to the foodstuffs in the storage.

Front view of cooling storage according to Embodiment 1 top view of cold storage Block diagram of the first refrigerating circuit and the second refrigerating circuit Sectional drawing which expands and shows a refrigerating unit and its periphery Block diagram showing the electrical configuration of the cold storage Schematic diagram of operation panel Cooling operation timing chart Refrigerant leak detection timing chart (when refrigerant leak occurs in the inverter refrigeration circuit) Refrigerant leak detection timing chart (when refrigerant leak occurs in the constant speed refrigeration circuit) Front view of cooling storage according to Embodiment 2 Cross-sectional view of AA line shown in FIG. Block diagram of refrigeration circuit Perspective view of refrigeration unit Block diagram showing the electrical configuration of the cold storage Schematic diagram of operation panel Refrigerant leak detection timing chart (if refrigerant leaks from the low pressure circuit on the freezer compartment side) Refrigerant leak detection timing chart (when refrigerant leaks from the high-pressure circuit)

<Embodiment 1>
Embodiment 1 will be described with reference to FIGS. 1 to 9. FIG. In the following description, the vertical direction and the horizontal direction are based on the vertical direction and the horizontal direction shown in FIG. 1, and the front-rear direction is based on the front-rear direction shown in FIG.

(1) Overall configuration of refrigerator As shown in FIG. 1, a refrigerator 1 (an example of a cold storage) according to Embodiment 1 is a four-door refrigerator, and includes a storage body 11 having an opening on the front side and an upper side of the storage body 11. , an operation panel 13 provided on the front surface of the machine room 12, four legs 14 provided on the bottom surface of the storage body 11, and the like.

The opening of the storage body 11 is partitioned into four by a cross-shaped front frame 11E. The interior of the storage main body 11 is not partitioned and forms one storage chamber. A pair of left and right heat insulating doors 10 (an example of doors) are vertically attached to the storage body 11, and four openings are individually opened and closed by these heat insulating doors 10. As shown in FIG.

The operation panel 13 receives various settings and instructions from the user. The operation panel 13 also displays various kinds of information regarding the refrigerator 1 . A substrate of the operation panel 13 is provided with an ambient temperature thermistor 33 (not shown) (see FIG. 5, an example of an ambient temperature sensor) for detecting the ambient temperature of the refrigerator 1 .

As shown in FIG. 2, the upper side of the machine room 12 is open. The machine room 12 accommodates a part of the refrigerating unit 15, an electrical box (not shown), an operation panel 13, a power source (not shown), and the like. The refrigerating unit 15 includes an inverter refrigerating circuit 16 (see FIG. 3, an example of a second refrigerating circuit) and a constant speed refrigerating circuit 17 (see FIG. 3, a first refrigerating circuit), which will be described later, on a heat insulating unit base 15A (see FIG. 4). (an example of a refrigeration circuit) is attached. A control unit 30 (see FIG. 5), which will be described later, is housed in an electrical equipment box (not shown).

As shown in FIG. 3, the inverter refrigerating circuit 16 includes an inverter compressor 16A with a variable rotation speed, an inverter condenser 16B (an example of a second condenser), an inverter decompression mechanism 16C (capillary tube or the like), an inverter evaporator 16D (an example of a second evaporator), etc., and these are circulatingly connected by a refrigerant pipe 16E.

The constant-speed refrigerating circuit 17 includes a constant-speed compressor 17A with a constant rotation speed, a constant-speed condenser 17B (an example of a first condenser), a constant-speed decompression mechanism 17C (capillary tube, etc.), and a constant-speed evaporator. 17D (an example of a first evaporator) and the like, which are circulated and connected by a refrigerant pipe 17E.

The inverter condenser 16B and the constant-speed condenser 17B are formed by dividing one condenser into front and rear parts, and one condenser fan 18 is provided for cooling them. A filter (not shown) is provided on the front side of the condenser (inverter condenser 16B and constant speed condenser 17B) to prevent dust in the air from adhering to the condenser and reducing the condensation capacity. . The inverter condenser 16B is provided with an inverter clogging thermistor 31 (see FIG. 5) (not shown) for detecting filter clogging based on temperature. Similarly, the constant-speed condenser 17B is provided with a constant-speed clogging thermistor 32 (see FIG. 5) for detecting filter clogging based on temperature.

The inverter evaporator 16D and the constant speed evaporator 17D are formed by dividing one evaporator into upper and lower parts. A defrosting thermistor 34 (see FIG. 5) (not shown) is attached to the inverter evaporator 16D. A defrosting thermistor 34 is for determining the end of the defrosting operation, which will be described later.

The configuration of the refrigerating unit 15 and its surroundings will be described with reference to FIG. Here, the inverter refrigerating circuit 16 will be described as an example. The refrigerating unit 15 has a unit base 15A, and an inverter refrigerating circuit 16 and a constant speed refrigerating circuit 17 are attached to the unit base 15A. The unit table 15A is formed in a shape one size larger than the opening 11B formed in the ceiling wall 11A of the storage body 11, and is arranged on the ceiling wall 11A so as to block the opening 11B.

The inverter evaporator 16D is attached to the lower side of the unit base 15A and accommodated in a cooling chamber 20 formed by the ceiling (the ceiling wall 11A and the unit base 15A) and the air duct 19. FIG. The air duct 19 forms a cooling chamber 20 between itself and the ceiling, and also functions as a drain pan for receiving defrosted water, which is water in which frost adhering to the evaporator has melted.

The air duct 19 has a substantially flat bottom wall 19A that slopes downward toward the rear side, side walls 19B that rise upward from the left and right edges of the bottom wall 19A, and upward from the rear edge of the bottom wall 19A. It has a rear wall 19C that rises slightly.

A circular suction port 19D for drawing air into the cooling chamber 20 is formed in the front portion of the bottom wall 19A. The rear wall 19C is spaced forward from the rear wall 11C of the storage body 11, and an air outlet 19E is formed between the rear wall 19C and the rear wall 11C of the storage body 11. As shown in FIG. A drain groove 19F having a U-shaped cross section extending rearward from the center in the left-right direction is formed integrally with the rear wall 19C. A drainage passage 11D is formed inside the rear wall 11C of the storage body 11, and the rear end of the drainage groove 19F is inserted into the drainage passage 11D. The defrosted water received by the air duct 19 is discharged out of the refrigerator through the drainage groove 19F and the drainage passage 11D.

An internal fan 21 is attached to the suction port 19D of the air duct 19 from above. When the inside fan 21 rotates, the air inside the refrigerator is sucked into the cooling chamber 20 through the suction port 19D, cooled by the inverter evaporator 16D, and blown into the refrigerator through the blowout port 19E.
In the cooling chamber 20, an in-chamber thermistor 22 (an example of an in-chamber temperature sensor and detection unit) for detecting the in-chamber temperature is arranged between the in-chamber fan 21 and the inverter evaporator 16D.

(2) Electrical Configuration of Refrigerator The electrical configuration of the refrigerator 1 will be described with reference to FIG. The refrigerator 1 has a control section 30 . The control unit 30 includes an operation panel 13, an inverter compressor 16A, a constant speed compressor 17A, a condenser fan 18, an internal fan 21, an internal thermistor 22, an inverter clogging thermistor 31, a constant speed clogging thermistor 32, An ambient temperature thermistor 33, a defrosting thermistor 34, and the like are connected.

The control unit 30 includes a microcomputer 30A, a ROM 30B, etc., in which a CPU, a RAM, etc. are integrated into one chip and mounted on a substrate. Microcomputer 30A controls each part of refrigerator 1 by executing a control program stored in ROM 30B.

(3) Operation Panel The operation panel 13 will be described with reference to FIG. The operation panel 13 includes a display unit 40 that displays various information such as the inside temperature and an alarm number to be described later in seven segments, and a plurality of display lamps 41 (inspection lamp 41A, filter lamp 41B, defrosting lamp 41C, ECO lamp 41D), a plurality of operation buttons 42, and the like. A plurality of operation buttons 42 are used by the user to perform various settings such as a target temperature (hereinafter referred to as set temperature) and various instructions to the refrigerator 1 .

(4) Control Processing Executed by the Control Unit Of the control processing executed by the control unit 30, door opening detection, condenser filter clogging detection, cooling operation, auxiliary cooling operation, refrigerant leakage detection, and refrigerant leakage will be described.

(4-1) Door open detection Door open detection is a process of detecting that the heat insulation door 10 is opened. As a method for detecting that the heat insulation door 10 is opened, various methods are possible, such as a method of judging from the rise in the temperature inside the refrigerator, a method of using a human sensor, and a method of using a door open/close switch interlocked with the opening and closing of the door. is.

In the method of judging from the increase in the internal temperature, the internal temperature is repeatedly detected by the internal thermistor 22 at intervals of one second or the like. When the heat insulating door 10 is opened, outside air enters the inside of the refrigerator, and the inside temperature rises greatly in a short time. Therefore, for example, when the internal temperature rises by 0.2 K [Kelvin] or more in 5 seconds, it is determined that the heat insulating door 10 has been opened.

In the method using a human sensor, a human sensor is provided in the refrigerator toward the heat insulation door 10 side. When a person in front of the refrigerator 1 opens the heat insulating door 10, the opening of the heat insulating door 10 is detected by detection of infrared rays by a human detection sensor.

In the method using a door open/close switch, for example, a door open/close switch comprising a magnet provided on the heat insulating door 10 and a reed switch provided on the storage body 11 is used. When the heat insulating door 10 is opened, the magnet moves away from the reed switch, so that the reed switch is turned on (or off), and the opening of the heat insulating door 10 is detected. Conversely, when the heat insulation door 10 is closed, the magnet approaches the reed switch and the reed switch is turned off (or on), thereby detecting that the heat insulation door 10 is closed.

In the case of the method of judging from the rise in temperature inside the refrigerator, there is no need to provide new parts such as a motion sensor and a door open/close switch. For this reason, in this embodiment, a method of judging from the increase in the internal temperature is used in order to suppress an increase in the number of parts. That is, in this embodiment, the internal thermistor 22 that detects the internal temperature also serves as a detection unit.

(4-2) Detection of Clogging of Condenser Filter When the filters of the condensers (inverter condenser 16B and constant-speed condenser 17B) are clogged, even if the condenser fan 18 rotates, There is insufficient heat exchange between them, and the cooling efficiency decreases. Therefore, the control unit 30 detects clogging of the filter using clogging thermistors (inverter clogging thermistor 31 and constant speed clogging thermistor 32).

Specifically, the control unit 30 detects the temperature of the condenser at predetermined sampling intervals using a clogged thermistor, and if the state in which the temperature of the condenser is equal to or higher than a predetermined threshold continues for a predetermined time or longer, the condenser fan 18 is turned off. increase the number of revolutions. If the temperature of the condenser does not decrease even when the rotation speed of the condenser fan 18 is increased, the control unit 30 determines that the filter is clogged, and lights the filter lamp 41B to prompt cleaning of the filter.

(4-3) Cooling Operation The cooling operation will be described with reference to FIG. In the cooling operation, the inverter compressor 16A and the condenser fan 18 are switched on/off to maintain the inside temperature within a predetermined cooling temperature range. The upper limit temperature of the cooling temperature range is, for example, set temperature +1.7 K [Kelvin], and the lower limit temperature is set temperature -2.0 K [Kelvin].

In the cooling operation, the control unit 30 operates the inverter compressor 16A, the condenser fan 18 and the inside fan 21, and stops the inverter compressor 16A and the condenser fan 18 when the inside temperature drops to the lower limit temperature. When these are stopped, the inside temperature rises gradually. The controller 30 restarts the operation of the inverter compressor 16A and the condenser fan 18 when the inside temperature rises to the upper limit temperature. By repeating this, the inside temperature is generally maintained within the cooling temperature range.

(4-4) Auxiliary Cooling Operation Auxiliary cooling operation will be described with reference to FIG. In FIG. 8, time point P1 is the time point when refrigerator 1 is turned on. When the power of the refrigerator 1 is turned on, the control unit 30 waits for a predetermined time (time point P2), and then operates the inverter compressor 16A, the condenser fan 18, and the internal fan 21 so that the internal temperature is not shown. The rotation speed of the inverter compressor 16A is controlled so as to fall along a predetermined target temperature curve (an example of a target line). Then, when the inside temperature drops to the upper limit temperature of the cooling temperature range, the control unit 30 switches to the cooling operation.

However, due to the high ambient temperature, the internal temperature may not fall along the target temperature curve. Therefore, when the inside temperature is higher than the upper limit temperature of the cooling temperature range and does not decrease along the target temperature curve, the control unit 30 operates the constant speed compressor 17A (time point P3). When the constant-speed compressor 17A is operated in an auxiliary manner, the control unit 30 starts constant-speed compression when the internal temperature drops to a temperature lower than the set temperature by a predetermined value (for example, 1.0 K) (set temperature -1.0 K). machine 17A is stopped (time point P4).

(4-5) Defrosting Operation When the cooling operation described above is performed, frost adheres to the evaporators (inverter evaporator 16D and constant speed evaporator 17D). Therefore, the controller 30 starts a defrosting operation for defrosting the evaporator when a predetermined defrosting start condition is satisfied. Defrosting start conditions include the arrival of a preset defrosting start time, the passage of a certain period of time from the end of the previous defrosting operation, and the user's instruction to start the defrosting operation.

In the defrosting operation, the controller 30 stops the compressors (the inverter compressor 16A and the constant speed compressor 17A), and rotates the internal fan 21 to promote defrosting. When the compressor is stopped, the temperature of the evaporator gradually rises. When the temperature of the evaporator detected by the defrosting thermistor 34 rises to a predetermined defrosting end temperature, the control unit 30 ends the defrosting operation and restarts the cooling operation.
A defrosting heater (not shown) may be placed under the evaporator, the internal fan 21 may be stopped, and the defrosting heater may be energized to defrost.

(4-6) Detecting Refrigerant Leakage The control unit 30 detects the temperature of the inverter condenser 16B at regular intervals under the condition that the heat insulating door 10 is not opened and the ambient temperature is equal to or lower than a predetermined temperature. The difference between (the temperature detected by the inverter clogging thermistor 31) and the ambient temperature (the temperature detected by the ambient temperature thermistor 33) is within a predetermined range continuously for a predetermined number of times or more, or at regular intervals If the difference between the temperature of the constant-speed condenser 17B (the temperature detected by the constant-speed clogging thermistor 32) and the ambient temperature is within a predetermined range for more than a predetermined number of times, it is determined that a refrigerant leak has occurred. do.

First, referring to FIG. 8, the case where refrigerant leakage occurs in the inverter refrigerating circuit 16 will be specifically described. In the example shown in FIG. 8, since the internal temperature does not rise by 0.2 K or more in 5 seconds at least after time P5, opening of the heat insulating door 10 is not detected at least after time P5. In addition, the ambient temperature is 50° C. (an example of the predetermined temperature) or less at least after time point P5. Therefore, in the example shown in FIG. 8, the condition that the opening of the heat insulation door 10 is not detected and the ambient temperature is equal to or lower than the predetermined temperature is satisfied in the period after time P5.

In the example shown in FIG. 8, when the above conditions are satisfied, the difference between the temperature of the inverter condenser 16B and the ambient temperature is 1 to 3 K (a certain range) every 30 seconds (an example of a certain period of time). One example) is within 6 consecutive times (an example of a fixed number of times) or more. Therefore, control unit 30 determines that a refrigerant leak has occurred at point P6 when the difference between the temperature of inverter condenser 16B and the ambient temperature is within the range of 1 to 3 K in succession six times.

Next, referring to FIG. 9, the case where refrigerant leakage occurs in the constant-speed refrigeration circuit 17 will be specifically described. In the example shown in FIG. 9, since the internal temperature does not rise by 0.2 K or more in 5 seconds after time P7, opening of the heat insulating door 10 is not detected at least after time P7. In addition, the ambient temperature is 50° C. (an example of a predetermined temperature) or less at least after time point P7. Therefore, in the example shown in FIG. 9, the condition that the opening of the heat insulation door 10 is not detected and the ambient temperature is equal to or lower than the predetermined temperature is satisfied in the period after time P7.

In the example shown in FIG. 9, the difference between the temperature of the constant speed condenser 17B and the ambient temperature is 1 to 3 K (constant (an example of the range) is continued six times (an example of a certain number of times) or more. Therefore, the control unit 30 determines that a refrigerant leak has occurred at time P8 when the difference between the temperature of the constant speed condenser 17B and the ambient temperature is within the range of 1 to 3 K in succession six times.

(4-7) Predetermined Processing Regarding Refrigerant Leakage When the control unit 30 determines that refrigerant leakage has occurred, it executes predetermined processing regarding refrigerant leakage. Specifically, the control unit 30 executes the following processes.
- Stop the compressor of the refrigerating circuit where refrigerant leakage has occurred, and operate the compressor of the other refrigerating circuit where refrigerant leakage has not occurred. When refrigerant leakage occurs in the constant-speed refrigeration circuit 17, the inverter compressor 16A is operated at the maximum rotational speed.
• Always operate the condenser fan 18 .
- Always operate the internal fan 21 .
・Control so that the defrosting operation that is performed regularly is not performed. It should be noted that the defrosting operation, which is performed irregularly, may also not be performed.
・Warning of refrigerant leakage. In the refrigerant leakage alarm, the control unit 30 blinks the inspection lamp 41A of the operation panel 13, and alternately displays the inside temperature and the refrigerant leakage alarm number on the display unit 40. FIG. Specifically, the control unit 30 displays the inside temperature when the inspection lamp 41A is off, and displays the alarm number when the inspection lamp 41A is on.

Note that at least one of the processes described above may be executed, and not all of them may be executed. The processing to be executed can be appropriately selected.

(5) Effect of the Embodiment According to the refrigerator 1 according to the first embodiment, when a refrigerant leak occurs in one of the refrigeration circuits, the compressor of the refrigeration circuit in which the refrigerant leakage has occurred is stopped, and the refrigerant leakage occurs. Operate the compressor of the other refrigeration circuit that is not Stopping the compressor of the refrigeration circuit in which the refrigerant leakage has occurred can reduce the speed of the refrigerant leakage, so that the leaked refrigerant can be prevented from accumulating in one place. Moreover, since the compressor of the other refrigeration circuit in which no refrigerant leakage has occurred is operated, it is possible to suppress an increase in the temperature inside the refrigerator. Therefore, according to the refrigerator 1, when a refrigerant leak occurs, it is possible to prevent the leaked refrigerant from accumulating in one place while suppressing an increase in the temperature inside the refrigerator.
Also, stopping the compressor of the refrigeration circuit in which refrigerant leakage has occurred can reduce the possibility of damage to the refrigeration circuit. Specifically, once all of the refrigerant has leaked out of the refrigeration circuit, there is a possibility that the refrigeration circuit will be damaged by subsequent ingress of moisture into the refrigeration circuit. On the other hand, if the compressor of the refrigerating circuit in which refrigerant leakage has occurred is stopped, it is possible to prevent all the refrigerant from leaking out, making it difficult for moisture to enter. Therefore, the possibility of damage to the refrigeration circuit can be reduced.

According to the refrigerator 1, when refrigerant leakage occurs in any of the refrigeration circuits, the control unit 30 can reduce the influence of the refrigerant leakage by executing a predetermined process regarding the refrigerant leakage.

According to the refrigerator 1, when refrigerant leakage occurs in the constant-speed refrigeration circuit 17, the predetermined processing includes processing for operating the inverter compressor 16A at the maximum rotation speed. It is possible to more reliably suppress an increase in the temperature inside the storage when it occurs.

According to the refrigerator 1, the predetermined processes are the process of operating the condenser fan 18, the process of operating the internal fan 21, the process of prohibiting the defrosting operation for defrosting the evaporator, and the process of alarming refrigerant leakage. including at least one of
When the condenser fan 18 is always operated, in the case of refrigerant leakage outside the refrigerator, the leaked refrigerant can be diffused outside the refrigerator. Therefore, when the refrigerant is a combustible refrigerant, it is possible to reduce the risk of the leaked combustible refrigerant remaining in one place.
Further, when the inside fan 21 is operated, the refrigerant can be gradually diffused outside the refrigerator through a small gap between the heat insulating door 10 and the storage main body 11 in the case of refrigerant leakage inside the refrigerator. Therefore, when the refrigerant is a flammable refrigerant, it is possible to reduce the risk of the flammable refrigerant leaking out of the refrigerator remaining in one place.
In addition, by prohibiting the defrosting operation, it is possible to suppress adverse effects on the foodstuffs stored in the cold storage.
In addition, when a refrigerant leakage warning is given, the user can be urged to refrain from opening and closing the heat insulating door 10 . When the opening and closing of the heat insulating door 10 is refrained from, the temperature inside the refrigerator is less likely to rise, so the possibility of damage to the foodstuffs inside the refrigerator can be suppressed. In addition, when a refrigerant leak warning is issued, the user can be encouraged to ventilate the room. Therefore, it is possible to reduce the risk of the flammable refrigerant leaking out of the refrigerator staying inside the refrigerator. In addition, when a refrigerant leak alarm is issued, the user can promptly request service from the manufacturer of the cold storage, thereby suppressing the possibility of damage to the foodstuffs in the storage.

<Embodiment 2>
Embodiment 2 will be described with reference to FIGS. 10 to 17. FIG. A refrigerator-freezer 200 (an example of a cooling storage compartment) according to Embodiment 2 has a refrigerating compartment (an example of a first storage compartment) and a freezing compartment (an example of a second storage compartment). It cools both the refrigerator and freezer compartments.

As shown in FIG. 10, the refrigerator-freezer 200 is of a two-door type, and includes a storage body 211 having openings 201 (201A and 201B, see FIG. 11) on the front side, a machine room 212 arranged above the storage body 211, It has an operation panel 213 provided on the front surface of the machine room 212, four legs 214 provided on the bottom surface of the storage body 211, and the like.

The operation panel 213 receives various settings and instructions from the user. The operation panel 213 also displays various kinds of information regarding the freezer-refrigerator 200, such as the internal temperature. A substrate of the operation panel 213 is provided with an ambient temperature thermistor 251 (see FIG. 14, an example of an ambient temperature sensor) for detecting the ambient temperature of the refrigerator/freezer 200 .

As shown in FIG. 11, a heat-insulating partition plate 215 is attached to the center of the storage body 211 in the vertical direction. divided into Two heat-insulating doors 218 (218A and 218B) are vertically attached to the front side of the storage body 211, and the freezer compartment 216 and the refrigerator compartment 217 are individually opened and closed by these heat-insulating doors 218. The heat insulating door 218A is an example of a second door, and the heat insulating door 218B is an example of a first door.

The upper side of the machine room 212 is open. The machine room 212 accommodates a part of the refrigerating unit 219, an electrical box (not shown), an operation panel 213, a power unit (not shown), and the like. The refrigerating unit 219 has a refrigerating circuit 220 (see FIG. 12) attached to a heat-insulating unit base 219A. A control unit 250 (see FIG. 14), which will be described later, is accommodated in an electrical equipment box (not shown).

Referring to FIG. 12, refrigerating circuit 220 will be described. The refrigeration circuit 220 includes a compressor 221, a condenser 222, a dryer 223, a switching valve 224 (three-way valve), a freezer decompression mechanism 225 (capillary tube or the like), a freezer compartment evaporator 226 (an example of a second evaporator), It has a refrigerator decompression mechanism 227 (capillary tube or the like), a refrigerator compartment evaporator 228 (an example of a first evaporator), and the like, and these are circulatingly connected by a refrigerant pipe 229 . The refrigeration circuit 220 also has a condenser fan 230 that cools the condenser 222 .

The outlet side of the compressor 221 is connected to the inlet side of the condenser 222 via a refrigerant pipe 229 . The outlet side of the condenser 222 is connected to the inlet side of the switching valve 224 via the refrigerant pipe 229 and the dryer 223 . The switching valve 224 switches the path of the refrigerant condensed by the condenser 222 to at least one of the refrigerating compartment evaporator 228 and the freezing compartment evaporator 226 (only the refrigerating compartment evaporator 228 is opened, only the freezer compartment evaporator 226 is opened or It is a so-called three-way valve that selectively switches to (both chambers open). The switching valve 224 has two outlets. One outlet of the switching valve 224 is connected to the inlet side of the freezer compartment evaporator 226 through the refrigerant pipe 229, and the other outlet is through the refrigerant pipe 229. It is connected to the inlet side of the refrigerator compartment evaporator 228 . The refrigerant pipe 229 connected to the outlet side of the freezer compartment evaporator 226 and the refrigerant pipe 229 connected to the outlet side of the refrigerator compartment evaporator 228 join in the middle and are connected to the inlet side of the compressor 221. It is

A filter (not shown) is provided in front of the condenser 222 to prevent dust in the air from adhering to the condenser 222 and condensing ability from deteriorating. A clogging thermistor (not shown) is attached to the condenser 222 to detect clogging of the filter based on the temperature of the condenser 222 .

In the following description, from the compressor 221 to the switching valve 224 is a high-pressure circuit, from the switching valve 224 to the freezing compartment evaporator 226 is a freezing compartment side low-pressure circuit, and from the switching valve 224 to the refrigerating compartment evaporator 228 is a refrigerating compartment. It is called the side low voltage circuit.

Refrigerating unit 219 will be described with reference to FIG. 13 . The refrigerating unit 219 has an adiabatic unit base 219A. A part of the refrigerating circuit 220 is attached to the unit base 219A. Since the refrigerating compartment evaporator 228 cools the inside of the refrigerating compartment 217, it is spaced downward from the unit table 219A.

The configuration of the refrigerating unit 219 and its surroundings will be described with reference to FIG. 11 . The freezer compartment evaporator 226 is attached to the lower side of the unit base 219A and accommodated in a freezer compartment cooling compartment 271 formed by the ceiling and the freezer compartment air duct 235 . A freezer compartment defrosting thermistor 234 (see FIG. 14) (not shown) is attached to the freezer compartment evaporator 226 . A freezer compartment internal fan 231 is attached to the freezer compartment air duct 235 .
A freezer compartment internal thermistor 232 for detecting the internal temperature of the freezer compartment 216 (second internal An example of a temperature sensor and a second detection unit) are arranged.

Inside the refrigerator compartment 217, a plate-shaped air duct 233 for the refrigerator compartment is arranged with the plate surface facing the front-rear direction. A cooling chamber 272 is formed. A refrigerating compartment evaporator 228 is accommodated in the refrigerating compartment cooling compartment 272 . A refrigerator-compartment defrosting thermistor 244 (see FIG. 14) (not shown) is attached to the refrigerator-compartment evaporator 228 .

A suction port 240 for sucking air into the cooling chamber 272 for the refrigerating chamber is formed between the refrigerating chamber air duct 233 and the bottom surface of the refrigerating chamber 217 . A blowout port 241 is formed between the refrigerator compartment air duct 233 and the partition plate 215 . An internal fan 242 for a refrigerating compartment is attached to the air outlet 241 . When the refrigerating compartment inside fan 242 rotates, the air in the refrigerating compartment 217 is sucked into the refrigerating compartment cooling compartment 272 through the suction port 240 , cooled by the refrigerating compartment evaporator 228 , and blown into the refrigerating compartment 217 through the outlet 241 . is blown out.
A refrigerating compartment internal thermistor 243 (a first internal temperature sensor and a first detection part) is arranged.

(2) Electrical Configuration of Refrigerator-Freezer The electrical configuration of the refrigerator-freezer 200 will be described with reference to FIG. 14 . The refrigerator/freezer 200 includes a control unit 250 . The control unit 250 includes an operation panel 213, a compressor 221, an ambient temperature thermistor 251, a condenser fan 230, a clogging thermistor 254, a freezer compartment internal fan 231, a freezer compartment internal thermistor 232, and a freezer compartment defrost thermistor. 234, a refrigerating compartment internal fan 242, a refrigerating compartment internal thermistor 243, a refrigerating compartment defrosting thermistor 244, a switching valve 224, and the like are connected.

The control unit 250 includes a microcomputer 250A, a ROM 250B, etc., in which a CPU, a RAM, etc. are integrated into one chip and mounted on a substrate. Microcomputer 250A controls each part of refrigerator/freezer 200 by executing a control program stored in ROM 250B.

(3) Operation Panel The operation panel 213 will be described with reference to FIG. The operation panel 213 has a display unit 260 that displays the internal temperature of the freezer compartment 216, an alarm number (to be described later), etc. in seven segments, and a display part 261 that displays the internal temperature of the refrigerator compartment 217, an alarm number (to be described later), etc. in seven segments. It is substantially the same as the operation panel 13 of Embodiment 1 except that it is provided.

(4) Control Processing Executed by Control Unit Of the control processing executed by the control unit 250, predetermined processing relating to cooling operation, refrigerant leak detection, and refrigerant leakage will be described.

(4-1) Cooling Operation A cooling operation according to the second embodiment will be described with reference to FIG. In FIG. 16, time point P1 is the time point when refrigerator-freezer 200 is powered on. When the power is turned on, the controller 250 operates the compressor 221, the condenser fan 230, the inside fan 231 for the freezer compartment, and the inside fan 242 for the refrigerator compartment after a predetermined time (time point P2).

Then, the control unit 250 alternately opens the switching valve 224 to the freezer compartment 216 side and the refrigerator compartment 217 side so that the internal temperatures of both storage compartments (the freezer compartment 216 and the refrigerator compartment 217) both reach the lower limit of the cooling temperature range. When the temperature drops below the temperature, the compressor 221 and the condenser fan 230 are stopped (time point P3). When the compressor 221 and the condenser fan 230 are stopped, the controller 250 opens the switching valve 224 in both chambers.

Then, when the internal temperature of one of the storage compartments rises to the upper limit temperature of the cooling temperature range after that, the control unit 250 switches to the storage compartment (freezer compartment 216 in FIG. 16) whose internal temperature has risen to the upper limit temperature. While opening the switching valve 224, the compressor 221 and the condenser fan 230 are operated again (time P4).

(4-2) Refrigerant leak detection The control unit 250 detects that the heat insulating door 218 of each storage compartment (freezing compartment 216 and refrigerating compartment 217) has not been opened, and the ambient temperature has reached a predetermined level. A state in which the switching valve 224 is opened and refrigerant is supplied to the evaporator of the storage compartment under the condition that the temperature is below the temperature and the difference between the temperature of the condenser 222 and the ambient temperature is a predetermined value or more. , it is determined that a refrigerant leak has occurred when the rate of increase in the internal temperature of the storage chamber is equal to or greater than a predetermined value for a predetermined number of times or more.

First, referring to FIG. 16, the case where refrigerant leakage occurs in freezer compartment 216 will be described. Point P5 in FIG. 16 is the point at which refrigerant leakage occurs in freezer compartment 216 . In the example shown in FIG. 16, the switching valve 224 is switched to the freezer compartment 216 side at time P4, and the refrigerant is supplied to the freezer compartment evaporator 226 during the period from time P4 to time P6.

Since the internal temperature of freezer compartment 216 does not rise by 0.2 K or more in five seconds from time P5 to time P6, opening of heat insulation door 218A of freezer compartment 216 is not detected. Further, the ambient temperature is 50° C. (an example of a predetermined temperature) or less during the period from time P5 to time P6. Also, during the period from time P5 to time P6, the difference between the temperature of condenser 222 detected by clogging thermistor 254 and the ambient temperature detected by ambient temperature thermistor 251 is 3K (an example of a predetermined value) or more.

Therefore, in the example shown in FIG. 16, during the period from time point P5 to time point P6, opening of the heat insulating door 218A of the freezer compartment 216 is not detected, the ambient temperature is equal to or lower than the predetermined temperature, and It satisfies the condition that the difference between the temperature of the condenser 222 and the ambient temperature is equal to or greater than a predetermined value.

During the period from time point P5 to time point P6, the refrigerant is being supplied to the freezer compartment evaporator 226, and in this state, the internal temperature of the freezer compartment 216 rises every 30 seconds (an example of a certain period of time). The width of 0.1K (an example of a constant value) or more continues six times (an example of the constant number of times) or more. Therefore, control unit 250 determines that refrigerant leakage has occurred in freezer compartment 216 at time point P6 when the range of temperature increase in freezer compartment 216 is 0.1 K or more in succession six times.

Although the details will be described later, when refrigerant leakage occurs in the freezer compartment 216, the control unit 250 switches the switching valve 224 to the refrigerator compartment 217 side in order to suppress the leakage speed of the refrigerant. Therefore, the refrigerant is supplied only to the refrigerator compartment evaporator 228 after time P6.

In the example shown in FIG. 16, when the switching valve 224 is switched to the refrigerating compartment 217 side at time P6, the temperature inside the refrigerating compartment 217 decreases. Therefore, after time point P6, the condition that the internal temperature rise of 0.1 K or more in each 30-second interval continues six times or more is not satisfied. Therefore, control unit 250 determines that refrigerant leakage does not occur in refrigerating chamber 217 at time point P7 after a predetermined period of time has elapsed from time point P6. In other words, control unit 250 determines that refrigerant leakage has occurred only in freezer compartment 216 .

Although the case where refrigerant leakage occurs in the freezer compartment 216 has been described here, the same applies to the case where refrigerant leakage occurs in the refrigerator compartment 217 .

Next, with reference to FIG. 17, a case where refrigerant leakage occurs in both freezer compartment 216 and refrigerator compartment 217 will be described. In FIG. 17, time points P1 to P6 are the same as in FIG. 16, so description thereof will be omitted.
In the example shown in FIG. 17, the opening of the heat insulating door 218B of the refrigerating compartment 217 is not detected in the period after time P6, the ambient temperature is equal to or lower than the predetermined temperature, and the temperature of the condenser 222 is It satisfies the condition that the difference from the ambient temperature is equal to or greater than a predetermined value. Even if the switching valve 224 is switched to the refrigerating chamber 217 side at the time point P6, the temperature inside the refrigerating chamber 217 is still rising, and the temperature rise of the refrigerating chamber 217 every 30 seconds is 0.1K or more. A certain thing continues six times or more (not shown in FIG. 17). Therefore, control unit 250 determines that a refrigerant leak has occurred in refrigerating chamber 217 at time point P8 when the rate of increase in the internal temperature of refrigerating chamber 217 is 0.1 K or more every 30 seconds in succession six times or more. to decide. In other words, controller 250 determines that refrigerant leakage has occurred in both freezer compartment 216 and refrigerator compartment 217 .

(4-3) Predetermined Processing Related to Refrigerant Leakage When control unit 250 determines that refrigerant leakage has occurred, it executes predetermined processing regarding refrigerant leakage. Specifically, the following processing is executed.

• Always operate the condenser fan 230 .
・Always operate the internal fan on the side of the refrigeration circuit where the refrigerant leak has occurred.
・Control so that the defrosting operation that is performed regularly is not performed. It should be noted that the defrosting operation, which is performed irregularly, may also not be performed.
・Warning of refrigerant leakage. In the refrigerant leakage alarm, the control unit 250 blinks the check lamp on the operation panel 213, and alternately displays the inside temperature and the refrigerant leakage alarm number on the display unit 260 (or the display unit 261).
In addition, in the refrigerant leakage alarm, if the refrigerant leakage occurs only in the freezer compartment 216, the control unit 250 detects that the refrigerant leakage occurs from the low-pressure circuit (from the switching valve 224 to the freezer compartment evaporator 226) on the freezer compartment 216 side. If a refrigerant leak occurs only in the refrigerator compartment 217, the refrigerant is released from the low-pressure circuit (from the switching valve 224 to the refrigerator compartment evaporator 228) on the refrigerator compartment 217 side. An alarm number indicating that there is a high possibility of leakage is displayed, and if refrigerant leakage occurs in both storage compartments (freezing compartment 216 and refrigerating compartment 217), the high-pressure circuit (compressor 221 to the switching valve 224), an alarm number indicating that there is a high possibility of refrigerant leakage is displayed.
- When refrigerant leakage occurs in the low-pressure circuit, the switching valve 224 is switched so that the refrigerant does not flow to the low-pressure circuit side where the refrigerant leakage occurs.

(5) Effect of the Embodiment According to the refrigerator-freezer 200 according to the second embodiment, it is not detected that the door of each storage compartment (the freezing compartment 216 and the refrigerating compartment 217) is opened. Under the conditions that the temperature is 50° C. or less and the difference between the temperature of the condenser 222 and the ambient temperature is 3 K or more, the switching valve 224 is opened to supply the refrigerant to the evaporator of the storage compartment. If the increase in the internal temperature of the storage chamber is 0.1 K or more every 30 seconds in a state where the storage chamber is in a state where the temperature rise is 0.1 K or more in succession six times or more, predetermined processing regarding refrigerant leakage will be executed. Unnecessary execution of the predetermined process can be suppressed when opening and closing are frequently performed, or when the compressor 221 is stopped due to a failure.

In addition, according to the freezer-refrigerator 200, a worker who repairs a refrigerant leak can determine whether the refrigerant is leaking from any of the low-pressure circuit on the freezer compartment 216 side, the low-pressure circuit on the refrigerating compartment 217 side, or the high-pressure circuit on the freezing circuit 220 side. Since it is possible to know from the alarm number whether the leakage is high or not, it becomes easy to identify the location where the refrigerant leakage is occurring. Therefore, refrigerant leakage can be repaired efficiently.

In addition, according to the freezer-refrigerator 200, when refrigerant leakage occurs in the low-pressure circuit, the switching valve 224 is switched so that the refrigerant does not flow to the low-pressure circuit side where the refrigerant leakage occurs. can be suppressed.

<Other embodiments>
The technology disclosed in this specification is not limited to the embodiments described in the above description and drawings, and the following embodiments are also included in the technical scope disclosed in this specification.

(1) In the first embodiment, the refrigerator is used as the cooling storage, but the cooling storage may be a freezer.

(2) In the above second embodiment, the freezer-refrigerator has been described as an example of a refrigerator having two storage compartments, but both of the two storage compartments may be refrigerator compartments or freezer compartments.

(3) In Embodiment 2, there are three opening/closing patterns for the switching valve 224: only the refrigerator compartment evaporator 228 is open, only the freezer compartment evaporator 226 is open, or both compartments are open. Only two patterns of open and freezer compartment evaporator 226 only open may be used.

(4) Various numerical values exemplified in the above embodiment are examples. These numerical values are not limited to those exemplified in the above embodiment.

DESCRIPTION OF SYMBOLS 1... Refrigerator (an example of a cooling storage), 10... Insulated door (an example of a door), storage body, 11... Storage body, 11B... Opening, 16... Inverter refrigerating circuit (an example of a second refrigerating circuit), 16A... Inverter compressor 16B... Inverter condenser (an example of a second condenser) 16D... Inverter evaporator (an example of a second evaporator) 17... Constant-speed refrigerating circuit (of the first refrigerating circuit) 17A constant-speed compressor 17B constant-speed condenser (an example of a first condenser) 17D constant-speed evaporator (an example of a first evaporator) 22 internal thermistor ( Example of internal temperature sensor and detection unit), 30 Control unit, 33 Ambient temperature thermistor (an example of ambient temperature sensor), 200 Refrigerator-freezer (an example of cooling storage), 201 Opening, 216 Freezing compartment (No. 1 example of storage room), 217... refrigerating room (an example of a second storage room), 218A... heat insulating door (an example of a second door), 218B... heat insulating door (an example of a first door), 220... Refrigeration circuit 221 Compressor 222 Condenser 224 Switching valve 226 Evaporator for freezer compartment (an example of second evaporator) 228 Evaporator for refrigerator compartment (an example of first evaporator ), 230 ... condenser fan, 231 ... freezer compartment internal fan (an example of an internal fan), 232 ... freezer compartment internal thermistor (an example of a second internal temperature sensor and a second detection unit), 242... Inside fan for refrigerator compartment (an example of an inside fan), 243... Inside thermistor for refrigerator compartment (an example of a first inside temperature sensor and a first detection unit), 251... Ambient temperature thermistor (an example of an ambient temperature Example of sensor)

Claims (4)

a cold store,
a storage body having an opening;
a door that opens and closes the opening;
a first refrigeration circuit having a constant speed compressor with a constant number of revolutions, a first condenser and a first evaporator;
a second refrigeration circuit having a variable speed inverter compressor, a second condenser, and a second evaporator;
an internal temperature sensor for detecting internal temperature;
a detection unit that detects that the door is opened;
an ambient temperature sensor for detecting ambient temperature;
a control unit;
with
The control unit
A cooling operation in which the inverter compressor is operated to cool the inside of the refrigerator, in which the inverter compressor is stopped when the temperature inside the refrigerator drops to the lower limit temperature of the cooling temperature range, and after that, the temperature inside the refrigerator falls within the cooling temperature range. cooling operation for resuming operation of the inverter compressor when the temperature rises to the upper limit temperature of
an auxiliary cooling operation for auxiliary cooling the inside of the refrigerator by operating the constant speed compressor when the temperature inside the refrigerator is higher than the upper limit temperature and the temperature inside the refrigerator has not decreased along a predetermined target line; ,
Under the condition that the opening of the door is not detected by the detection unit and the ambient temperature is equal to or lower than a predetermined temperature, the temperature of the first condenser and the ambient temperature are changed at regular intervals. is within a predetermined range for a certain number of times or more, or the difference between the temperature of the second condenser and the ambient temperature is within a predetermined range for a certain number of times or more. determining that refrigerant leakage has occurred in the first refrigerating circuit or the second refrigerating circuit, and that the difference between the first refrigerating circuit and the second refrigerating circuit is within the predetermined range; stop the constant speed compressor or the inverter compressor of the refrigerating circuit in which the constant number of times or more has continued, and operate the inverter compressor or the constant speed compressor of the other refrigerating circuit . The cold store of claim 1,
The cooling storage, wherein the control unit executes a predetermined process regarding refrigerant leakage when the difference is within the predetermined range consecutively for the predetermined number of times or more. A cold store according to claim 2,
The predetermined process includes a process of operating the inverter compressor at a maximum rotation speed when the difference in the first refrigerating circuit is within the predetermined range for the predetermined number of times or more. . The cooling storage according to claim 2 or claim 3 ,
The predetermined process includes a process of operating a condenser fan that cools the first condenser and the second condenser, the air cooled by the first evaporator, and the air cooled by the second evaporator. a process of operating an internal fan that circulates the depleted air in the compartment; a process of prohibiting the defrosting operation of defrosting the first evaporator and the second evaporator ; and a process of alarming refrigerant leakage. refrigerated storage, comprising at least one of

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