JP7465135B2 - Cooling Storage - Google Patents

Description

The technology disclosed in this specification relates to refrigerated storage.

Conventionally, a cooling storage unit is known that includes a storage chamber with a door, a cooling device in which a compressor and a cooler (evaporator) are circulated and connected by a refrigerant pipe, an internal fan that circulates the air in the storage chamber, a temperature measuring unit that measures the internal temperature in the storage chamber, and a control unit that controls the operation of the compressor, the internal fan, etc. For example, the following Patent Document 1 discloses a cooling storage unit that performs cooling operation in a so-called controlled cooling mode, in which the internal temperature is maintained in a constant temperature range by driving/stopping the compressor based on the internal temperature. In the controlled cooling mode, the cooling fan (internal fan) is usually kept driving. In addition, a cooling storage unit that performs defrosting operation in a so-called off-cycle defrosting mode, in which the compressor is stopped while the internal fan is kept driving in order to remove frost formed on the cooler during cooling operation, is also known.

JP 2005-121341 A

In a cooling storage facility, the temperature inside the facility can rise suddenly due to various factors, such as the door of the storage room being opened wide and warm outside air flowing in, causing the pressure in the refrigerant pipes to rise. When the compressor is stopped and a gas-liquid mixture of refrigerant with a high liquid content is trapped in the refrigerant pipes of the cooler, and the warm air inside the facility is sent to the cooler by the operation of the interior fan, the refrigerant in the cooler vaporizes, causing the pressure in the refrigerant pipes to rise, especially on the suction side (low pressure side) from the cooler to the compressor. If the control unit attempts to start the compressor when the refrigerant pressure exceeds the compressor's performance value (allowable suction pressure), the compressor may fail to start and be unable to continue operating.

The technology disclosed in this specification was developed based on the above circumstances, and aims to provide a refrigerated storage facility with reduced compressor malfunctions.

In order to solve the above problems, the cooling storage disclosed in this specification has the following configuration.
<1> A storage apparatus comprising: a storage chamber in which an item to be stored is accommodated; a compressor that compresses a refrigerant; a cooler that evaporates the refrigerant compressed by the compressor and performs heat exchange; a refrigerant pipe in which the refrigerant is sealed and that circulates between the compressor and the cooler; an internal fan that sends internal air in the storage chamber to the cooler and circulates cold air generated by heat exchange in the cooler back into the storage chamber; a temperature measurement unit that measures the internal temperature of the storage chamber or the temperature of the cooler; and a control unit that controls operation of the compressor and the internal fan, wherein while the compressor is stopped and the internal fan is being driven, the control unit compares a temperature measurement value measured by the temperature measurement unit with a predetermined fan stop temperature, and when it is determined that the temperature measurement value is higher than the fan stop temperature, stops the internal fan, and starts the compressor after stopping the internal fan.

According to the above configuration, when the compressor is stopped and the measured temperature value exceeds a predetermined fan stop temperature, the in-cabinet fan is stopped before the compressor is started. This makes it difficult for the heated in-cabinet air to reach the cooler, and reduces the increase in refrigerant pressure on the low-pressure side of the refrigerant pipe leading from the cooler to the compressor. As a result, it is possible to suppress an increase in the load when the compressor is started, and reduce startup failures of the compressor. Note that the fan stop temperature is preferably set to a temperature slightly lower than the temperature at which the compressor can be started when both the compressor and the in-cabinet fan are stopped.

<2> In the configuration of <1> above, a timer unit is further provided that measures the drive time, which is the elapsed time from the most recent start of the compressor, while the compressor is in operation. When the compressor is started with the internal fan stopped, the control unit compares the drive time measurement value measured by the timer unit with a predetermined fan restriction time, and if it is determined that the drive time measurement value is not longer than the fan restriction time, it does not start the internal fan, and if it is determined that the drive time measurement value is longer than the fan restriction time, it starts the internal fan.

According to the above configuration, after the compressor is started with the internal fan stopped, a certain time (fan restriction time) passes and the part of the refrigerant with the highest pressure on the low-pressure side of the refrigerant pipe passes through the compressor, and then the internal fan is restarted. This reduces the greatest load on the compressor and reduces the possibility of a situation occurring in which the compressor cannot continue to operate.

<3> In the configuration of <1> or <2> above, the temperature measurement unit is an internal temperature measurement unit that measures the internal temperature in the storage chamber, the measured temperature is an internal temperature measurement unit measured by the internal temperature measurement unit, the fan stop temperature is a fan stop internal temperature that is higher than a predetermined upper limit internal temperature, and the control unit is further provided with a timing unit that measures a stop time that is the elapsed time since the compressor was most recently stopped, and the control unit compares the internal temperature measurement with a lower limit internal temperature that is lower than the upper limit internal temperature, and when it determines that the internal temperature measurement is lower than the lower limit internal temperature, stops the compressor, and compares the internal temperature measurement with the upper limit internal temperature and when it determines that the internal temperature measurement is higher than the upper limit internal temperature The stop time measurement value measured by the timer is compared with a predetermined compressor restriction time, and if it is determined that the stop time measurement value is not longer than the compressor restriction time, the compressor is not started, and if it is determined that the stop time measurement value is longer than the compressor restriction time, the compressor is started to perform a cooling operation that maintains the internal temperature in the storage chamber within a predetermined temperature range. During the cooling operation, while the internal fan is being driven, the internal temperature measurement value is compared with the fan stop internal temperature, and if it is determined that the internal temperature measurement value is higher than the fan stop internal temperature, the operating state of the compressor is referenced, and if it is determined that the compressor is stopped, the internal fan is stopped.

During cooling operation to maintain the internal temperature within a predetermined temperature range, it is preferable to perform control based on the internal temperature measurement value. In the above cooling operation, if the internal temperature measurement value exceeds the upper internal temperature limit, a predetermined time (compressor restriction time) has elapsed, the pressure difference between the low-pressure side and the high-pressure side of the refrigerant pipe has become small, and the pressure in the refrigerant circuit has been equalized, and then the compressor is started. According to the above configuration, if the internal temperature rises suddenly while the internal fan is driven during such cooling operation, and the internal temperature measurement value exceeds the fan stop internal temperature with the compressor stopped, the internal fan is first stopped. This suppresses the rise in refrigerant pressure on the low-pressure side of the refrigerant pipe. As a result, the increase in the load when the compressor starts can be suppressed, and the compressor start-up failure can be reduced.

<4> In the configuration of <1> or <2> above, the temperature measurement unit is a cooler temperature measurement unit that measures the temperature of the cooler, the measured temperature is a cooler temperature measurement unit measured by the cooler temperature measurement unit, the fan stop temperature is a fan stop cooler temperature that is lower than a predetermined defrost end cooler temperature, the control unit executes a defrosting operation to remove frost on the cooler by stopping the compressor, and during the defrosting operation, the control unit compares the measured cooler temperature with the defrost end cooler temperature and, if it is determined that the measured cooler temperature is higher than the defrost end cooler temperature, starts the compressor and ends the defrosting operation, and, if it is determined that the measured cooler temperature is higher than the defrost end cooler temperature while the internal fan is driven during the defrosting operation, the internal fan is stopped.

During the defrosting operation for removing frost from the cooler, it is preferable to perform control based on the cooler temperature measurement value. The above-mentioned defrosting operation is terminated when the cooler temperature measurement value exceeds the defrost end cooler temperature, and the compressor is started. As in the past, if the in-compartment fan is continued to be driven during the defrosting operation regardless of the temperature measurement value, if the in-compartment temperature rises due to some factor before the end of the defrosting operation, the operation of the in-compartment fan causes the refrigerant to evaporate in the cooler, causing the refrigerant pressure on the low-pressure side of the refrigerant pipe to rise, and the compressor may not be able to start when the temperature measurement value exceeds the defrost end cooler temperature. According to the above configuration, when the cooler temperature measurement value exceeds the fan stop cooler temperature while the in-compartment fan is being driven during the defrosting operation in which the compressor is stopped, the in-compartment fan is first stopped, and then the compressor is started after waiting for the cooler temperature measurement value to further rise to the defrost end cooler temperature. As a result, even if the temperature inside the cabinet rises suddenly before the compressor starts, that is, between when the cooler temperature measurement reaches the fan stop cooler temperature and when it reaches the defrost end cooler temperature, the rise in refrigerant pressure on the low pressure side of the refrigerant pipe is suppressed compared to when the inside fan continues to drive. As a result, it is possible to reduce the occurrence of problems when starting the compressor at the end of the defrost operation.

<5> In the configuration of <3> above, the control unit further includes a cooler temperature measurement unit that measures the temperature of the cooler, and the control unit performs a defrosting operation to remove frost on the cooler by stopping the compressor during a period when the cooling operation is not being performed, and compares the cooler temperature measurement value measured by the cooler temperature measurement unit with a predetermined defrost end cooler temperature, and if it is determined that the cooler temperature measurement value is higher than the defrost end cooler temperature, starts the compressor and ends the defrosting operation. During the defrosting operation, while the internal fan is driven, the control unit compares the cooler temperature measurement value with a fan stop cooler temperature that is lower than the defrost end cooler temperature, and if it is determined that the cooler temperature measurement value is higher than the fan stop cooler temperature, stops the internal fan.

In a cooling storage configured to perform both cooling and defrosting operations, if the inside fan is stopped based on the measured inside temperature during defrosting operation, the cooler temperature may not rise and the frost may not be sufficiently removed. Also, if the inside fan is configured to continue to be driven during defrosting operation regardless of the measured inside temperature, if the inside temperature rises sharply just before the end of the defrosting operation, the operation of the inside fan may increase the refrigerant pressure on the low-pressure side of the refrigerant pipe, and the compressor may not be able to start after the defrosting operation ends. According to the above configuration, during cooling operation, the inside fan is stopped based on a comparison between the measured inside temperature and the fan-stop inside temperature, while during defrosting operation, the inside fan is stopped when the measured cooler temperature reaches the fan-stop cooler temperature. This not only reduces compressor start failures during cooling operation in a cooling storage that selectively performs cooling operation and defrosting operation, but also reduces compressor start failures at the end of the defrosting operation while sufficiently removing frost from the cooler during defrosting operation.

The technology disclosed in this specification makes it possible to provide a cooling storage facility with reduced compressor malfunctions.

FIG. 1 is an external perspective view of a cooling storage unit according to an embodiment (with the door open); Vertical cross-section of the cooling storage facility (door closed) FIG. 1 is an exploded perspective view showing a state in which a cooler, spacers, etc. are attached to the ceiling surface of a storage room. FIG. 3 is an exploded perspective view showing the state in which the air duct and the interior fan are attached. A block diagram showing a configuration related to control of a cooling storage facility. A flowchart showing an example of a process of the control unit during a cooling operation. 1 is a timing chart showing an example of the operating states of the compressor and the internal fan and changes in the measured internal temperature during cooling operation. A flowchart showing an example of a process of a control unit during a defrosting operation. 1 is a timing chart showing an example of the operating states of the compressor and the internal fan and changes in the measured cooler temperature during defrosting operation.

<Embodiment>
An embodiment of the present invention will be described with reference to FIGS.
1, the cooling storage facility 10 of this embodiment includes a cart section 12 having a plurality of casters (one example of wheels) 11, and a vertically long storage facility main body 13 standing on the cart section 12, and can be easily moved. In this embodiment, a total of four casters are attached to each of the four corners of the rectangular bottom surface of the cart section 12.

Inside the storage body 13, there is a storage chamber 15 that contains stored items and opens to the front, and a machine chamber 16 located below the storage chamber 15. A door 14 is attached to the front of the storage chamber 15, allowing the user to open and close the opening at the front of the storage chamber 15 as needed. The walls that define the storage chamber 15 and the inside of the door 14 are filled with insulating material, and when the door 14 is closed, the inside of the storage chamber 15 is maintained in an insulated state. Note that in the cross-sectional view of Figure 2, the insulating material has been omitted in order to prioritize ease of viewing.

The cooling storage 10 is equipped with a cooling device 30 for cooling the inside of the storage room 15. As shown in FIG. 2, the cooling device 30 includes a well-known refrigeration cycle in which a compressor 33, a condenser 31, and a cooler 35 are circulated and connected by a refrigerant pipe 34. As shown in the figure, in the cooling storage 10 according to this embodiment, each device constituting the cooling device 30 is arranged in a separate state in the machine room 16 below the storage room 15 and in the upper part of the storage room 15. Such a mobile cooling storage is suitable, for example, in a hotel or the like, for storing food cooked in the kitchen in the storage room of the cooling storage and moving it to a banquet hall or the like to serve it in a cold state. In a cooling storage used in this way, the door is opened for a long time in order to serve food to a large number of customers in a timely manner. In addition, since it is formed relatively small for mobility and the storage room is often small in capacity, it is easy for a situation to occur in which the temperature inside the storage rises suddenly. This technology can be particularly effectively applied to such a cooling storage 10.

The configuration arranged inside the machine room 16 will be described.
2, among the components constituting the cooling device 30, the machine room 16 is provided with a compressor 33 and a condenser 31, which are heavy, and a condenser fan 32 attached to the back of the condenser 31. The compressor 33, the condenser 31, and a cooler (evaporator) 35, which will be described later, are circulated and connected by a refrigerant pipe 34. A refrigerant is sealed in the refrigerant pipe 34, and the refrigerant compressed by the compressor 33 and liquefied by the condenser 31 is supplied to the cooler 35. In this way, the refrigerant is circulated in the refrigeration cycle while changing its state, and heat exchange is performed, thereby cooling the inside of the storage chamber 15, as will be described later.

The refrigerant pipes 34 can be divided into a discharge side refrigerant pipe 34A (high pressure side refrigerant pipe) that discharges the refrigerant discharged from the compressor 33 toward the cooler 35 after passing through the condenser 31, and a suction side refrigerant pipe 34B (low pressure side refrigerant pipe) that sucks the refrigerant returned from the cooler 35 back into the compressor 33. The discharge side refrigerant pipe 34A is exposed to dissipate the heat of the compressed and high temperature refrigerant, while the suction side refrigerant pipe 34B is wrapped in a heat insulating material made of foam or the like to prevent condensation from the refrigerant returned to the compressor 33 at a relatively low temperature. Hereinafter, when they are to be distinguished, they will be referred to as the discharge side refrigerant pipe 34A and the suction side refrigerant pipe 34B, and when they are not to be distinguished, they will be referred to as the refrigerant pipe 34.

In addition to the compressor 33, condenser 31, and condenser fan 32, an electrical box 57 is also installed in the machine room 16, as shown by the dashed lines in FIG. 1. The electrical box 57 houses a control unit 60 for controlling the operation of each device equipped in the cooling storage cabinet 10, as described below. In addition, an operation unit 65, for example, constituted by a push button, and a display unit 67, for example, constituted by a liquid crystal panel, may be provided on the front surface of the electrical box 57 facing the front end of the machine room 16, and an openable cover constituted by a transparent resin plate or glass plate may be attached to the front surface of the machine room 16.

The configuration disposed in the upper part of the storage chamber 15 will be described.
2 and 3, the cooler 35, one of the components constituting the cooling device 30, is disposed in an upper rear position within the storage chamber 15. As shown in Fig. 3, the cooler 35 is fixed to the ceiling surface of the storage chamber 15. The above-mentioned refrigerant pipe 34 is connected to the rear end of the cooler 35, and is connected to the compressor 33 and the condenser 31 in a circulating manner.

As shown in FIG. 3, an internal thermistor (an example of an internal temperature measuring unit) 41 is attached to the ceiling surface of the storage chamber 15 above the internal fan 53, which is attached in front of the cooler 35 as described below. The internal thermistor 41 measures the temperature of the internal air drawn into the cooler chamber 52 by the internal fan 53, i.e., the internal temperature. A cooler thermistor (a defrosting thermistor, an example of a cooler temperature measuring unit) 43 is attached to the inside of the cooler 35 so as to be inserted therein and measures the temperature inside the cooler 35, i.e., the cooler temperature. The attachment position of the internal thermistor 41 is not particularly limited, and it can be installed at any position in the cooling storage chamber as long as it is possible to measure the change in the internal temperature. It is preferable that the cooler thermistor is installed at a position where it is not easily affected by the change in the internal temperature and where the temperature inside the cooler can be measured. A metal spacer 51A is further fixed to the ceiling surface of the storage chamber 15 so as to surround the cooler 35 to which the cooler thermistor 43 is attached and the internal thermistor 41 at the rear.

As shown in FIG. 4, a plastic air duct 51B is attached to the underside of the spacer 51A, and as shown in FIG. 2, a cooler chamber 52 is formed between the ceiling surface of the storage chamber 15 and a housing member 51 consisting of the spacer 51A and the air duct 51B. The air duct 51B is attached so as to protrude forward of the cooler 35, and as shown in FIGS. 2 and 4, an internal fan 53 is attached to a position near the front of the air duct 51B. Also, as shown in FIGS. 2 and 4, the air duct 51B is attached so that a gap 54 is formed between the rear end of the air duct 51B and the back surface of the storage chamber 15, and the cooler chamber 52 and the storage chamber 15 are in communication with each other.

The housing member 51 also functions as a drain pan to receive defrost water from the cooler 35. As shown in Figs. 2 and 4, the housing member 51 has a shape in which the bottom surface slopes downward toward the rear, so that water dripping from the cooler 35 onto the housing member 51 flows toward the rear. A drain hose 59 is connected to the lowest position at the rear end of the housing member 51. As shown in Fig. 2, the drain hose 59 extends through the inside of the rear wall of the storage chamber 15 to the machine chamber 16, and the defrost water generated in the cooler chamber 52 flows down the drain hose and accumulates in a drain tank detachably installed in the machine chamber 16.

The electrical configuration of the cooling storage facility 10 will now be described.
As shown in Fig. 5, the cooling storage 10 includes a control unit 60. The control unit 60 is electrically connected to a memory unit 61, a timer unit 63, an operation unit 65, a display unit 67, an internal thermistor 41, a cooler thermistor 43, a compressor 33, an internal fan 53, and a condenser fan 32. Note that these are only examples of configurations, and it is not necessary for all of these to be connected, and other components may also be connected. For example, if a defrost heater is attached to the cooler 35 and control in a heater defrost mode can also be executed, a defrost heater or the like can be connected.

The control unit 60 is mainly composed of a CPU, for example, and the memory unit 61 is composed of a ROM, a RAM, etc. The control unit 60 is capable of controlling the operation of each device connected to the control unit 60 (the compressor 33, the internal fan 53, the condenser fan 32, etc.) by executing a computer program stored in the memory unit 61. The timing unit 63 measures time, and functions as a cooling time measurement timer, a stop time measurement timer, and an operating time measurement timer. The measurement of each time will be described later.

As already described, the control unit 60 of the cooling storage unit 10 in this embodiment is housed in the electrical box 57 (see dashed line in FIG. 1) located in the machine room 16, but the arrangement of the control unit 60 is not limited. If the operation unit 65 and the display unit 67 are provided on the front of the electrical box 57 as already described in FIG. 1, for example, the user can operate the cooling storage unit 10 and perform various settings (such as changing the set internal temperature) by opening the cover on the front of the machine room and operating the buttons on the operation unit 65. In addition, the user can check the operating status displayed on the display unit 67 from the front of the cooling storage unit 10 through the cover on the front of the machine room.

The cooling storage facility 10 according to this embodiment is configured to alternate between a cooling operation, which appropriately cools the inside of the storage chamber 15 to maintain a predetermined temperature range, and a defrosting operation, which removes frost that has adhered to the cooler 35 by the cooling operation. For example, the cooling storage facility 10 can be configured to perform a defrosting operation every six hours, but is not limited to this.

During cooling operation, the internal fan 53, compressor 33, and condenser fan 32 are driven. When the internal fan 53 is driven, air in the storage chamber 15 is drawn into the cooler chamber 52, as shown by the arrow in FIG. 2. The drawn internal air undergoes heat exchange while passing through the cooler 35, and the generated cold air is blown out from the gap 54 behind the housing member 51 into the storage chamber 15 below. As described above, the inside of the storage chamber 15 is cooled by supplying cold air from the cooler chamber 52 into the storage chamber 15.

The cooling operation can be performed by combining a pull-down cooling mode, which cools the inside of the storage chamber 15 in one go from a state close to room temperature (e.g., 25°C) to a specified temperature range (e.g., 2°C to 6°C), and a controlled cooling mode, which maintains the temperature inside the chamber within the specified temperature range.

When frost forms on the cooler 35 during cooling operation, the cooling efficiency decreases. Therefore, the cooling storage 10 according to this embodiment is configured to pause cooling as appropriate and perform a defrosting operation to melt the frost that has formed on the cooler 35. In this embodiment, during defrosting operation, control is performed in an off-cycle defrosting mode in which the compressor 33 is stopped while the internal fan 53 continues to operate.

[Application Example 1]
The technology disclosed in this specification can be applied to control when performing cooling operation by executing the controlled cooling mode. In the controlled cooling mode, the control unit 60 drives/stops the compressor 33 and the condenser fan 32 based on the internal temperature measurement value TRm (one example of a temperature measurement value) measured by the internal thermistor 41, thereby maintaining the internal temperature within a predetermined temperature range. Note that the drive/stop of the condenser fan 32 is basically controlled in synchronization with the compressor 33, so the condenser fan 32 will not be described below.

In the following, the set internal temperature TRs, the upper limit internal temperature TRu, the lower limit internal temperature TRd, and the fan stop internal temperature TRfs (an example of the fan stop temperature) are all predetermined values and are set so that the lower limit internal temperature TRd < the set internal temperature TRs < the upper limit internal temperature TRu << the fan stop internal temperature TRfs. Specifically, for example, the lower limit internal temperature TRd = 2°C, the set internal temperature TRs = 4°C, and the upper limit internal temperature TRu = 6°C can be considered. In addition, it is preferable that the fan stop internal temperature TRfs is a temperature slightly lower than the temperature at which the compressor 33 can be started from a state in which both the compressor 33 and the internal fan 53 are stopped. For example, if it is found that the upper limit internal temperature at which the compressor 33 can be started from a state in which the compressor 33 and the internal fan 53 are stopped is 22°C, it is preferable to set the fan stop temperature to 20°C.

The cooling time refers to the time that has elapsed since the most recent cooling operation was started. When the control unit 60 starts the cooling operation, the timer unit 63 starts measuring the cooling time. Then, when the control unit 60 determines that the cooling time measurement value tRm has exceeded the defrost cycle time tD and transitions from the cooling operation to the defrost operation, the measurement of the cooling time is terminated and reset. The defrost cycle time tD is a predetermined value, and specifically, can be set to, for example, 6 hours.

The stop time refers to the time that has elapsed since the compressor 33 was most recently stopped during cooling operation. When the control unit 60 determines that the measured internal temperature TRm has fallen below the lower limit internal temperature TRd and stops the compressor 33, the timing unit 63 starts measuring the stop time. Then, when the control unit 60 determines that the measured internal temperature TRm has exceeded the upper limit internal temperature TRu and that the measured stop time tPm has exceeded the compressor restriction time tC and starts the compressor 33, the measurement of the stop time ends and is reset. The compressor restriction time tC is a predetermined value, and specifically, can be set to, for example, 3.5 minutes.

The drive time refers to the time that has elapsed since the compressor 33 was last started. When the control unit 60 starts the compressor 33 with the internal fan 53 stopped, the timing unit 63 starts measuring the drive time. Then, when the control unit 60 determines that the drive time measurement value tAm has exceeded the first fan regulation time tF1 and starts the internal fan 53, the measurement of the drive time is terminated and reset. The first fan regulation time tF1 (an example of a fan regulation time) is a predetermined value, and specifically, can be set to, for example, 10 seconds.

Below, an example of the processing performed by the control unit 60 when the present technology is applied to the controlled cooling mode will be specifically described with reference to FIG. 6. Note that the start, end, and reset of time measurement in the timing unit 63 may be performed based on commands from the control unit 60, but the processing related to time measurement is not shown in FIG. 6 (the same applies to FIG. 8).

When the power supply of the cooling storage unit 10 is turned on and control is started (START), the timer unit 63 starts measuring the cooling time. The control unit 60 drives the compressor 33 and the interior fan (step S11) and compares the interior temperature measurement value TRm with each interior temperature setting, for example, at a predetermined time interval.

As the internal temperature decreases due to the operation of the compressor 33, when the internal temperature measurement TRm is compared with the lower limit internal temperature TRd (step S12), if it is determined that the internal temperature measurement TRm falls below the lower limit internal temperature TRd (Yes in step S12), the control unit 60 stops the compressor 33 (step S31). At this time, the timing unit 63 starts measuring the stop time. While the internal temperature measurement TRm is in the temperature range between the lower limit internal temperature TRd and the upper limit internal temperature TRu (No in steps S12 and S13), the compressor 33 and internal fan 53 continue to be driven/stopped.

As the inside temperature rises due to the stop of the compressor 33, etc., the inside temperature measurement TRm is compared with the upper limit inside temperature TRu (step S13). If it is determined that the inside temperature measurement TRm exceeds the upper limit inside temperature TRu (Yes in step S13), the control unit 60 compares the stop time measurement value tPm measured by the timing unit 63 with the compressor restriction time tC (step S14). If it is determined that the stop time measurement value tPm does not exceed the compressor restriction time tC (No in S14), the control unit 60 compares the inside temperature measurement TRm with the fan stop inside temperature TRfs (step S15). Since the inside temperature rarely rises to exceed the fan stop inside temperature TRfs, the control unit 60 often determines that the inside temperature measurement TRm does not exceed the fan stop inside temperature TRfs (No in step S15). If the measured internal temperature TRm does not exceed the fan stop internal temperature TRfs (No in step S15) and it is determined that the measured stop time tPm exceeds the compressor restriction time tC (Yes in S14), the control unit 60 starts the compressor 33 (step S32).

Basically, in the controlled cooling mode, as described above, the comparison of the measured internal temperature TRm with the lower limit internal temperature TRd (step S12) and the comparison of the measured internal temperature TRm with the upper limit internal temperature TRu (step S13) are repeated. When the control unit 60 determines that the measured internal temperature TRm has fallen below the lower limit internal temperature TRd, it stops the compressor 33, and when it determines that the measured internal temperature TRm has exceeded the upper limit internal temperature TRu, it starts the compressor 33 after a certain period of time (compressor restriction time tC) has elapsed, thereby maintaining the internal temperature within a temperature range near the set internal temperature TRs.

The control unit 60 also appropriately compares the cooling time measurement value tRm measured by the timer unit 63 with the defrost cycle time tD (step S41). While it is determined that the cooling time measurement value tRm does not exceed the defrost cycle time tD (No in step S41), the control unit 60 continues the cooling operation in the controlled cooling mode, and when it is determined that the cooling time measurement value tRm exceeds the defrost cycle time tD (Yes in step S41), the control unit 60 transitions to the defrost operation shown in FIG. 8 (described later) (A).

During cooling operation in the controlled cooling mode as described above, the temperature inside the storage chamber 15 may suddenly rise if the door 14 is opened, for example.

First, a case where the inside temperature rises suddenly after the compressor restriction time tC has elapsed will be described. After determining that the inside temperature measurement value TRm has exceeded the upper limit inside temperature TRu (Yes in step S13), the control unit 60 determines that the stop time measurement value tPm has exceeded the compressor restriction time tC (Yes in step S14), and starts the compressor 33 (step S32). In this case, since the refrigerant pipe 34 is in a pressure equalization state due to the elapse of the compressor restriction time tC, starting the compressor 33 while continuing to drive the inside fan 53 is unlikely to cause a startup failure, and normal operation can be continued.

Next, a case will be described where the internal temperature rises suddenly before the compressor restriction time tC has elapsed. After the control unit 60 determines that the internal temperature measurement TRm has exceeded the upper limit internal temperature TRu (Yes in step S13), and before determining that the stop time measurement value tPm has exceeded the compressor restriction time tC (No in step S14), the control unit 60 determines that the internal temperature measurement TRm has exceeded the fan-stop internal temperature TRfs in comparison with the internal temperature measurement TRm in step S15 (Yes in step S15).

When it is determined that the measured internal temperature TRm exceeds the fan stop internal temperature TRfs (Yes in step S15), the control unit 60 refers to the operating state of the compressor 33 and determines whether the compressor 33 is stopped (driving) or not (step S16). When it is determined that the compressor 33 is not stopped (driving) (No in step S16), the control unit 60 continues control as is. When it is determined that the compressor 33 is stopped (Yes in step S16), the control unit 60 stops the internal fan 53 that has been continuously driven (step S21).

After stopping the internal fan 53, the control unit 60 continues to compare the stop time measurement value tPm with the compressor restriction time tC (step S22). While it is determined that the stop time measurement value tPm does not exceed the compressor restriction time tC (No in step S22), the control unit 60 does not start the compressor 33 and keeps it stopped. Then, when it is determined that the stop time measurement value tPm exceeds the compressor restriction time tC (Yes in step S22), the control unit 60 starts the compressor 33 (step S23).

When the compressor 33 is started, the timer 63 starts measuring the drive time. The control unit 60 compares the drive time measurement value tAm with the first fan regulation time tF1 (step S24). While it is determined that the drive time measurement value tAm has not reached the first fan regulation time tF1 (No in step S24), the control unit 60 does not start the internal fan 53 and keeps it stopped. When it is determined that the drive time measurement value tAm has exceeded the first fan regulation time tF1 (Yes in step S24), the control unit 60 starts the internal fan 53 (step S25).

The following describes in detail an example of the timing of driving/stopping the compressor 33 and the internal fan 53 and the change in the internal temperature measurement value TRm when the above-mentioned processing is performed, with reference to FIG. 7.

When the cooling operation starts and the compressor 33 and the interior fan 53 are started, the interior temperature measurement value TRm drops sharply from a relatively high value close to room temperature due to pull-down cooling. When the interior temperature measurement value TRm falls below the lower limit interior temperature TRd at time t1, the compressor 33 is stopped. If the door 14 of the storage chamber 15 is opened wide at time t2 before the compressor restriction time tC has elapsed while the compressor 33 is stopped and the interior fan 53 is kept driven, the interior temperature measurement value TRm rises sharply and exceeds the upper limit interior temperature TRu at time t3. If the interior temperature measurement value TRm rises further and exceeds the fan stop interior temperature TRfs at time t4 before the stop time measurement value tPm exceeds the compressor restriction time tC, the interior fan 53 is stopped. In this way, after both the compressor 33 and the internal fan 53 are maintained in a stopped state for a while, when the stop time measurement value tPm exceeds the compressor restriction time tC at time t5, the compressor 33 is started first while the internal fan 53 remains stopped. Then, when the drive time measurement value tAm exceeds the first fan restriction time tF1 at time t6, the internal fan 53 is restarted.

As described above, the refrigerated storage facility 10 of this embodiment comprises a storage chamber 15 in which stored items are stored, a compressor 33 that compresses a refrigerant, a cooler 35 that evaporates the refrigerant compressed by the compressor 33 and performs heat exchange, a refrigerant pipe 34 in which the refrigerant is sealed and which circulates between the compressor 33 and the cooler 35, an internal fan 53 that sends the internal air in the storage chamber 15 to the cooler 35 and circulates the cold air generated by heat exchange in the cooler 35 back into the storage chamber 15, an internal thermistor 41 (an example of a temperature measurement unit) that measures the internal temperature of the storage chamber 15, and a control unit 60 that controls the operation of the compressor 33 and the internal fan 53. Then, while the compressor 33 is stopped and the internal fan 53 is being driven, the control unit 60 compares the internal temperature measurement TRm (an example of a temperature measurement value) measured by the internal thermistor 41 with a predetermined fan-stop internal temperature TRfs (an example of a fan-stop temperature), and if it determines that the internal temperature measurement TRm is higher than the fan-stop internal temperature TRfs (Yes in steps S15 and S16), it stops the internal fan 53 (step S21) and starts the compressor 33 after stopping the internal fan 53 (step S23).

As a result, if the temperature inside the cabinet rises suddenly while the compressor 33 is stopped and the interior fan 53 is running, the interior fan 53 is stopped first. This makes it difficult for the heated interior air to reach the cooler 35, and reduces the increase in refrigerant pressure in the suction side refrigerant pipe 34B leading from the cooler 35 to the compressor 33. As a result, the increase in load when starting the compressor 33 after the interior fan 53 is stopped is suppressed, and startup failures of the compressor 33 are reduced.

The cooling storage 10 further includes a timer 63 that measures the drive time, which is the time elapsed since the compressor 33 was last started, while the compressor 33 is running. When the control unit 60 starts the compressor 33 with the internal fan 53 stopped (step S23), the control unit 60 compares the drive time measurement value tAm measured by the timer 63 with a predetermined first fan regulation time tF1 (an example of a phlegm regulation time) and determines that the drive time measurement value tAm is not longer than the first fan regulation time tF1 (No in step S24), does not start the internal fan 53, and when it determines that the drive time measurement value tAm is longer than the first fan regulation time tF1 (Yes in step S24), starts the internal fan 53 (step S25).

As a result, after the internal fan 53 is stopped and the compressor 33 is started, a certain time (first fan restriction time tF1) has elapsed, and the refrigerant portion with the highest pressure in the suction side refrigerant pipe 34B has passed through the compressor 33, and then the internal fan 53 is restarted. As a result, the greatest load on the compressor 33 is reduced, and the possibility of a situation occurring in which the compressor 33 cannot continue to operate is reduced.

In addition, in this application example, the cooling storage facility 10 further includes an internal thermistor 41 that measures the internal temperature in the storage chamber 15 as a temperature measuring unit, an internal temperature measurement value TRm measured by the internal thermistor 41 as a temperature measurement value, a fan stop internal temperature TRfs that is higher than a predetermined upper limit internal temperature TRu as a fan stop temperature, and a timing unit 63 that measures the stop time, which is the time since the compressor was most recently stopped. Then, the control unit 60 compares the internal temperature measurement TRm with the lower limit internal temperature TRd, and if it determines that the internal temperature measurement TRm is lower than the lower limit internal temperature TRd (Yes in step S12), it stops the compressor 33 (step S31). If it compares the internal temperature measurement TRm with the upper limit internal temperature TRu and determines that the internal temperature measurement TRm is higher than the upper limit internal temperature TRu (Yes in step S13), it compares the stop time measurement value tPm measured by the timing unit 63 with a predetermined compressor restriction time tC and determines that the stop time measurement value tPm is not longer than the compressor restriction time tC (No in step S14), it does not start the compressor 33 and stops the compressor 33 (step S31). If it is determined that the measured value tPm is longer than the compressor restriction time tC (Yes in step S14), the compressor 33 is started (step S32) to perform a cooling operation that maintains the internal temperature in the storage chamber 15 within a predetermined temperature range. During the cooling operation, while the internal fan 53 is driven, the internal temperature measurement TRm is compared with the fan-stop internal temperature TRfs. If it is determined that the internal temperature measurement TRm is higher than the fan-stop internal temperature TRfs (Yes in step S15), or if it is determined that the compressor 33 is stopped by referring to the operating state of the compressor 33 (Yes in step S16), the internal fan 53 is stopped (step S21).

During the cooling operation to maintain the inside temperature within a predetermined temperature range, it is preferable to perform control based on the inside temperature measurement value TRm. In the cooling operation of this application example, after the inside temperature measurement value TRm exceeds the upper limit inside temperature TRu, the compressor 33 is started after waiting for a certain time (compressor restriction time tC) to elapse. As a result, before the compressor 33 is started, the pressure difference between the suction side refrigerant tube 34B (low pressure side refrigerant tube) and the discharge side refrigerant tube 34A (high pressure side refrigerant tube) of the refrigerant tube 34 is reduced, and pressure equalization in the refrigerant circuit is achieved. According to the above configuration, when the inside temperature rises suddenly while the inside fan 53 is being driven and the inside temperature measurement value TRm exceeds the fan stop inside temperature TRfs with the compressor 33 stopped (Yes in steps S15 and S16), the inside fan 53 is stopped in step S21 before the compressor 33 is started in step S23. As a result, the rise in refrigerant pressure in the suction side refrigerant tube 34B is suppressed. As a result, the increase in the startup load when starting the compressor 33 in step S23 is suppressed, reducing startup failures of the compressor 33.

[Application Example 2]
The technology disclosed in this specification can be applied to control when performing a defrosting operation by executing an off-cycle defrosting mode. In the off-cycle defrosting mode, the control unit 60 melts and removes frost adhering to the cooler 35 by driving/stopping the compressor 33 and the condenser fan 32 based on a cooler temperature measurement value TEm (one example of a temperature measurement value) measured by the cooler thermistor 43.

The defrost end cooler temperature TEs and the fan stop cooler temperature TEfs (an example of the fan stop temperature) are both predetermined values and are set so that the defrost end cooler temperature TEs is greater than the fan stop cooler temperature TEfs. Specifically, it is considered that the defrost end cooler temperature TEs = 6°C and the fan stop cooler temperature TEfs = 5°C. The cooler thermistor 43 is preferably not easily affected by changes in the temperature inside the cabinet and is capable of measuring the cooler temperature inside the cooler 35.

As described above, the timer 63 functions as a cooling time timer, a stop time timer, and a drive time timer. During defrosting operation, the compressor 33 is started with the interior fan 53 stopped, and measurement of the drive time is started. When the control unit 60 determines that the drive time measurement value tAm exceeds the second fan regulation time tF2 (an example of a fan regulation time) and starts the interior fan 53, the timer 63 ends and resets the measurement of the drive time. The second fan regulation time tF2 is also a predetermined value, and specifically, for example, can be set to 10 seconds, the same as the first fan regulation time tF1, but the first fan regulation time tF1 and the second fan regulation time tF2 may be set to different values.

Below, an example of the processing performed by the control unit 60 when this technology is applied to the off-cycle defrost mode is specifically described with reference to FIG. 8.

When a predetermined time has elapsed since the start of the cooling operation and it is determined in step S41 of FIG. 6 that the cooling time measurement value tRm measured by the timer unit 63 exceeds the defrost cycle time tD (Yes in step S41), the control unit 60 transitions from the cooling operation to the defrost operation of FIG. 8 (A).

When defrosting operation begins, the control unit 60 stops the compressor 33 while keeping the internal fan 53 running (step S51), and compares the measured cooler temperature value TEm with each cooler temperature setting, for example at a predetermined interval.

As the cooler temperature slowly rises due to the stop of the compressor 33, when the cooler temperature measurement TEm is compared with the fan-stopped cooler temperature TEfs (step S52), if it is determined that the cooler temperature measurement TEm exceeds the fan-stopped cooler temperature TEfs (Yes in step S52), the control unit 60 stops the internal fan 53 (step S53).

After the internal fan 53 is stopped, as the cooler temperature continues to rise slowly, the controller 60 compares the cooler temperature measurement TEm with the defrost end cooler temperature TEs (step S54) and determines that the cooler temperature measurement TEm exceeds the defrost end cooler temperature TEs (Yes in step S53), and starts the compressor 33 (step S55).

After starting the compressor 33, the control unit 60 compares the drive time measurement value tAm measured by the timer unit 63 with the second fan regulation time tF2 (step S56). As long as it is determined that the drive time measurement value tAm does not exceed the second fan regulation time tF2 (No in step S56), it does not start the internal fan 53. If it is determined that the drive time measurement value tAm has exceeded the second fan regulation time tF2 (Yes in step S56), it restarts the internal fan 53 (step S57) and transitions to the cooling operation shown in FIG. 6 (B).

The following describes in detail an example of the timing of driving/stopping the compressor 33 and the internal fan 53 and the change in the measured cooler temperature value TEm when the above-mentioned processing is performed, with reference to FIG. 9.

When the defrosting operation is started and the compressor 33 is stopped while the drive of the interior fan 53 is maintained, the cooler temperature measurement value TEm slowly rises. When the cooler temperature measurement value TEm exceeds the fan stop cooler temperature TEfs at time t21, the interior fan 53 is stopped. When the cooler temperature measurement value TEm further rises and exceeds the defrost end cooler temperature TEs at time t22, the control unit 60 starts the compressor 33. Then, when the drive time measurement value tAm exceeds the second fan restriction time tF2 at time t23, the interior fan 53 is restarted. In this way, not only the compressor 33 but also the interior fan 53 are maintained in a stopped state for a certain period (between time t21 and time t22) before the cooler temperature measurement value TEm exceeds the defrost end cooler temperature TEs and the compressor 33 is started.

As described above, in this application example, the cooling storage facility 10 uses a cooler thermistor 43 (an example of a cooler temperature measurement unit) that measures the temperature of the cooler 35 as a temperature measurement unit, the cooler temperature measurement value TEm measured by the cooler thermistor 43 as a temperature measurement value, and the fan stop cooler temperature TEfs, which is lower than a predetermined defrost end cooler temperature TEs, as a fan stop temperature. The control unit 60 then performs a defrosting operation to remove frost from the cooler 35 by stopping the compressor 33. During the defrosting operation, the control unit 60 compares the cooler temperature measurement TEm with the defrost end cooler temperature TEs, and if it determines that the cooler temperature measurement TEm is higher than the defrost end cooler temperature TEs (Yes in step S54), it starts the compressor 33 and ends the defrosting operation (step S55). If it determines that the cooler temperature measurement TEm is higher than the fan stop cooler temperature TEfs while the internal fan 53 is being driven during the defrosting operation (Yes in step S52), it stops the internal fan 53 (step S53).

During the defrosting operation for removing frost from the cooler 35, it is preferable to perform control based on the cooler temperature measurement value TEm. The defrosting operation of this application example ends when the cooler temperature measurement value TEm exceeds the defrost end cooler temperature TEs, and the compressor 33 is started. As in the past, if the drive of the in-compartment fan 53 is continued during the defrosting operation regardless of the temperature measurement value, if the in-compartment temperature rises due to some factor within a predetermined time before the end of the defrosting operation, the operation of the in-compartment fan 53 causes the refrigerant to evaporate in the cooler 35, causing the refrigerant pressure in the suction side refrigerant pipe 34B to rise, and there is a possibility that the compressor 33 cannot be started when the cooler temperature measurement value TEm exceeds the defrost end cooler temperature TEs during the defrosting operation in which the compressor 33 is stopped (Yes in step S52), the in-compartment fan 53 is first stopped (step S53). Then, the compressor 33 is started (step S55) after waiting for the cooler temperature measurement TEm to further rise to the defrost end cooler temperature TEs (Yes in step S54). In the off-cycle defrost mode, the cooler temperature rises relatively slowly. For example, if the fan-stop cooler temperature TEfs is set to 5° C. and the defrost end cooler temperature TEs is set to 6° C., the cooler temperature measurement TEm exceeds the fan-stop cooler temperature TEfs at time t21, and then the cooler temperature measurement TEm rises further and exceeds the defrost end cooler temperature TEs at time t22. During this time, even if the door 14 of the storage chamber 15 is opened and the temperature inside the chamber rises rapidly, the inside fan 53 is stopped, so that the rise in the refrigerant pressure in the suction side refrigerant pipe 34B is suppressed compared to when the inside fan 53 is driven, and the increase in the pressure difference between the suction side refrigerant pipe 34B and the discharge side refrigerant pipe 34A is suppressed. As a result, the occurrence of problems when starting the compressor 33 in step S57 at the end of the defrosting operation is reduced.

The cooling storage 10 also includes both an internal thermistor 41 and a cooler thermistor 43. During periods when the cooling operation is not being performed, the control unit 60 performs a defrosting operation to remove frost on the cooler 35 by stopping the compressor 33. When the control unit 60 determines that the cooler temperature measurement TEm measured by the cooler thermistor 43 is higher than the defrost end cooler temperature TEs by comparing the cooler temperature measurement TEm with the predetermined defrost end cooler temperature TEs (Yes in step S54), it starts the compressor 33 and ends the defrosting operation (step S55). During the defrosting operation, the control unit 60 compares the cooler thermistor 43 with the fan stop cooler temperature TEfs, which is lower than the defrost end cooler temperature TEs, and when the control unit 60 determines that the cooler temperature measurement TEm is higher than the fan stop cooler temperature TEfs by comparing the cooler thermistor 43 with the fan stop cooler temperature TEfs, which is lower than the defrost end cooler temperature TEs, it stops the internal fan 53 (step S53).

In a cooling storage configured to perform both cooling and defrosting operations, such as the cooling storage 10, if the inside fan 53 is stopped based on the inside temperature measurement value TRm during defrosting operation, the cooler temperature may not rise and the frost may not be sufficiently removed. Also, if the inside fan 53 is configured to continue to be driven during defrosting operation regardless of the cooler temperature measurement value TEm, if the inside temperature rises sharply just before the end of the defrosting operation, the operation of the inside fan 53 may increase the refrigerant pressure in the suction side refrigerant pipe 34B, and the compressor 33 may not be able to start after the end of the defrosting operation. According to the above configuration, during cooling operation, the inside fan 53 is stopped based on a comparison between the inside temperature measurement value TRm and the fan stop inside temperature TRfs, while during defrosting operation, the inside fan 53 is stopped when the cooler temperature measurement value TEm reaches the fan stop cooler temperature TEfs. As a result, in the cooling storage facility 10 that selectively performs cooling and defrosting operations, not only can it reduce start-up failures of the compressor 33 during cooling operation, but it also reduces start-up failures of the compressor 33 at the end of defrosting operation while still allowing sufficient frosting to form on the cooler during defrosting operation.

<Other embodiments>
The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments, for example, are also included within the technical scope of the present invention.

(1) In the above embodiment, an example was described in which the present technology was applied to a cooling storage facility 10 in which a cooling operation and a defrosting operation are selectively performed, when the controlled cooling mode and the off-cycle defrosting mode are performed, but the present technology is not limited to this. It is also possible to apply the present technology to a cooling storage facility that performs only a cooling operation, and the present technology may not be applied during a cooling operation, but may be applied only during a defrosting operation.

(2) In the above embodiment, the defrosting operation is described as being performed in the off-cycle defrosting mode. However, for example, a defrosting heater may be attached to the underside of the cooler 35, and the defrosting operation may be performed by combining a heater defrosting mode in which the defrosting heater is heated to perform defrosting, and an off-cycle defrosting mode.

(3) In the above embodiment, the cooling operation is switched to the defrosting operation every time the cooling operation continues for a certain period of time, and when the temperature of the cooler rises to a predetermined temperature after the defrosting operation is started, the defrosting operation is terminated and the operation is switched back to the cooling operation. However, this is not limited to this. For example, the cooling efficiency of the cooling device 30 may be calculated to estimate the state of frost on the cooler 35, and when a certain state is reached, the defrosting operation may be started.

(4) In the above embodiment, an example is described in which the inside of the storage chamber 15 is maintained in a refrigerated temperature range of 2°C to 6°C, but this is not limited to this. The present technology can also be applied to freezers that are maintained in a freezing temperature range of 0°C or less. The specific examples of the set values related to temperature and time described in the above embodiment, as well as the set inside temperature TRs, are all merely examples and can be set arbitrarily depending on the purpose of use of the refrigerated storage chamber, the usage environment, etc.

(5) In the above embodiment, a single-door refrigerated storage unit 10 is described that is equipped with a means for moving (casters) and configured to be easily moved. The present technology is particularly useful for refrigerated storage units configured in such a way that the temperature inside the unit is relatively likely to rise, but is not limited to this. For example, the present technology can also be applied to refrigerated storage units that have multiple storage compartments and refrigerated storage units in which the multiple storage compartments are maintained at different temperature ranges.

10... refrigeration storage, 14... door, 15... storage room, 30... cooling device, 33... compressor, 34... refrigerant pipe, 34A... discharge side refrigerant pipe (high pressure side refrigerant pipe), 34B... suction side refrigerant pipe (low pressure side refrigerant pipe), 35... cooler (evaporator), 41... internal thermistor (an example of an internal temperature measuring unit), 43... cooler thermistor (an example of a cooler temperature measuring unit), 53... internal fan, 60... control unit, 63... timing unit, TRm... internal temperature measurement value , TRfs...Fan stopped inside temperature, TRs...Set inside temperature, TRd...Lower limit inside temperature, TRu...Upper limit inside temperature, TEm...Cooler temperature measurement, TEfs...Fan stopped cooler temperature, TEs...Defrost end cooler temperature, tPm...Stop time measurement, tF1...First fan restriction time, tF2...Second fan restriction time, tAm...Drive time measurement, tC...Compressor restriction time, tRm...Cooling time measurement, tD...Defrost cycle time

Claims (4)

A storage chamber in which the stored items are stored;
A compressor that compresses a refrigerant;
a cooler that performs heat exchange by evaporating the refrigerant compressed by the compressor;
a refrigerant pipe in which the refrigerant is sealed and which circulates between the compressor and the cooler;
An internal fan that sends internal air in the storage chamber to the cooler and circulates the cold air generated by heat exchange in the cooler back into the storage chamber;
A temperature measuring unit that measures the internal temperature of the storage chamber or the temperature of the cooler;
A control unit that controls operation of the compressor and the internal fan,
The control unit is
While the compressor is stopped and the interior fan is driven, the temperature measured by the temperature measuring unit is compared with a predetermined fan stop temperature,
When it is determined that the measured temperature is higher than the fan stop temperature, the interior fan is stopped,
After the internal fan is stopped, the compressor is started.
The temperature measurement unit is an internal temperature measurement unit that measures an internal temperature in the storage chamber,
The temperature measurement value is an internal temperature measurement value measured by the internal temperature measurement unit,
The fan stop temperature is a fan stop internal temperature that is higher than a predetermined upper limit internal temperature,
The compressor further includes a timer that measures a stop time that is an elapsed time from the most recent stop of the compressor.
The control unit is
The measured internal temperature is compared with a lower limit internal temperature which is lower than the upper limit internal temperature,
When it is determined that the measured internal temperature is lower than the lower limit internal temperature, the compressor is stopped,
The measured internal temperature is compared with the upper limit internal temperature,
When it is determined that the measured internal temperature is higher than the upper limit internal temperature, the stop time measured by the timer unit is compared with a predetermined compressor restriction time,
When it is determined that the measured stop time is not longer than the compressor restriction time, the compressor is not started.
When it is determined that the measured stop time value is longer than the compressor regulation time, the compressor is started to perform a cooling operation for maintaining the inside temperature of the storage chamber within a predetermined temperature range,
While the interior fan is driven in the cooling operation, the interior temperature measurement value is compared with the interior temperature when the fan is stopped,
When it is determined that the measured internal temperature is higher than the fan-stop internal temperature, referring to the operating state of the compressor,
The cooling storage facility stops the internal fan when it is determined that the compressor is stopped . A storage chamber in which the stored items are stored;
A compressor that compresses a refrigerant;
a cooler that performs heat exchange by evaporating the refrigerant compressed by the compressor;
a refrigerant pipe in which the refrigerant is sealed and which circulates between the compressor and the cooler;
An internal fan that sends internal air in the storage chamber to the cooler and circulates the cold air generated by heat exchange in the cooler back into the storage chamber;
A temperature measuring unit that measures the internal temperature of the storage chamber or the temperature of the cooler;
A control unit that controls operation of the compressor and the internal fan,
The control unit is
While the compressor is stopped and the interior fan is driven, the temperature measured by the temperature measuring unit is compared with a predetermined fan stop temperature,
When it is determined that the measured temperature is higher than the fan stop temperature, the interior fan is stopped,
After the internal fan is stopped, the compressor is started.
the temperature measurement unit is a cooler temperature measurement unit that measures a temperature of the cooler,
the temperature measurement value is a cooler temperature measurement value measured by the cooler temperature measurement unit,
The fan stop temperature is a fan stop cooler temperature that is lower than a predetermined defrost end cooler temperature,
The control unit is
By stopping the compressor, a defrosting operation is performed to remove frost from the cooler;
During the defrosting operation, the cooler temperature measurement value is compared with the defrost end cooler temperature,
When it is determined that the measured cooler temperature is higher than the defrost end cooler temperature, the compressor is started to end the defrost operation,
The cooling storage facility stops the internal fan when it is determined that the measured cooler temperature is higher than the fan stop cooler temperature while the internal fan is being driven in the defrosting operation . A cooler temperature measurement unit for measuring the temperature of the cooler is further provided,
The control unit is
During a period in which the cooling operation is not being performed, a defrosting operation is performed to remove frost from the cooler by stopping the compressor;
The cooler temperature measurement value measured by the cooler temperature measurement unit is compared with a predetermined defrost end cooler temperature,
When it is determined that the measured cooler temperature is higher than the defrost end cooler temperature, the compressor is started to end the defrost operation,
During the defrosting operation, while the interior fan is being driven,
Comparing the cooler temperature measurement with a fan-stop cooler temperature that is lower than the defrost end cooler temperature;
The refrigerated storage facility according to claim 1 , wherein the interior fan is stopped when it is determined that the measured cooler temperature is higher than the fan stop cooler temperature. The compressor further includes a timer that measures a drive time, which is an elapsed time from the most recent start of the compressor, while the compressor is being driven.
The control unit is
When the compressor is started while the internal fan is stopped,
The drive time measured by the timer unit is compared with a predetermined fan restriction time.
When it is determined that the measured drive time is not longer than the fan regulation time, the interior fan is not started,
The cooling storage facility according to claim 1 , wherein the internal fan is started when it is determined that the measured drive time value is longer than the fan restriction time.

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