JP2022186119A - Cooling storage warehouse - Google Patents

Abstract

To provide a cooling storage warehouse capable of reducing consumption of electric energy for defrosting operation.SOLUTION: A control section of a cooling storage warehouse performs defrosting operation until a temperature detected by a defrosting temperature sensor becomes a first defrosting termination temperature which is a temperature to terminate defrosting operation when at least one condition selected from the following four conditions is met: a first condition in which the number of times that a storage temperature detected by a storage temperature sensor becomes equal to or higher than a door opening-closing detection temperature, is equal to or less than the reference number of times during cooling operation; a second condition in which a set storage temperature becomes equal to or higher than a reference set temperature during the cooling operation; a third condition in which a difference between the storage temperature detected by the storage temperature sensor and the set storage temperature becomes equal to or less than a reference value during the cooling operation; and a fourth condition in which the temperature detected by the defrosting temperature sensor becomes equal to or higher than a reference defrosting temperature during the cooling operation. When any of the condition selected from the four conditions is met, the control section performs the defrosting operation until the temperature detected by the defrosting temperature sensor becomes a first defrosting termination temperature which is a temperature to terminate the defrosting operation. When any of the condition selected from the four conditions is not met, the control section performs the defrosting operation until the temperature detected by the defrosting temperature sensor becomes a second defrosting termination temperature which is a temperature to terminate the defrosting operation and higher than the first defrosting termination temperature.SELECTED DRAWING: Figure 8

Description

The technology disclosed in this specification relates to cold storage.

2. Description of the Related Art Conventionally, a refrigerator described in Patent Document 1 below is known as an example of a cold storage. The refrigerator described in Patent Document 1 includes an outside air temperature sensor that detects the outside air temperature, a defrosting temperature sensor that detects the temperature of the cooler or its vicinity, and the temperature detected by the defrosting temperature sensor. a control unit that terminates the defrosting operation when a defrosting set temperature for judging the end of frosting is reached, wherein the control unit controls the temperature detected by the outside air temperature sensor to be a first set temperature. It is determined whether it is lower than the temperature or higher than a second set temperature higher than the first set temperature, and if it is lower than the first set temperature or higher than the second set temperature, a defrosting end determination Defrosting operation is performed with the defrosting set temperature set to the first defrosting set temperature for defrosting end determination, and when the defrosting set temperature is between the first set temperature and the second set temperature, the defrosting for defrosting end determination The defrosting operation is performed with the defrosting setting temperature set to a second defrosting setting temperature for judging completion of defrosting, which is lower than the first defrosting setting temperature.

Japanese Patent No. 6270375

In Patent Document 1 described above, the defrosting preset temperature for judging the end of defrosting is varied based on the outside air temperature detected by the outside air temperature sensor. However, the influence of the outside air temperature on the temperature environment inside the refrigerator and the amount of frost formed on the cooler varies depending on factors such as the insulation performance of the main body of the storage and the frequency of opening and closing the door. Even if the defrosting preset temperature is set based on the above, there is a possibility that an appropriate defrosting operation according to the actual amount of frost formed on the cooler cannot be performed. For this reason, there is a possibility that power consumption cannot be sufficiently saved.

The technique described in this specification has been perfected based on the circumstances as described above, and aims to reduce power consumption.

(1) A cooling storage according to the technology described in this specification includes a storage main body having an opening, a door for opening and closing the opening, a first sensor for detecting the temperature inside the storage, and an evaporator constituting a refrigeration cycle. a heating unit that heats the evaporator; a second sensor that detects the temperature of the evaporator or the vicinity of the evaporator; a control unit that controls a refrigeration cycle to perform a cooling operation, and controls the heating unit to perform a defrosting operation until the temperature detected by the second sensor reaches a defrosting end temperature; detects opening and closing of the door when the internal temperature detected by the first sensor reaches or exceeds a predetermined door opening/closing detection temperature, and is detected by the first sensor during the cooling operation. a first condition that the number of times the temperature inside the refrigerator becomes equal to or higher than the door opening/closing detection temperature is equal to or less than a reference number of times; a second condition that the preset temperature inside the refrigerator is equal to or higher than the reference preset temperature during the cooling operation; a third condition that the difference between the inside temperature detected by the first sensor during the cooling operation and the inside preset temperature is equal to or less than a reference value; and the temperature detected by the second sensor during the cooling operation. is equal to or higher than the reference defrosting temperature, and when at least one selection condition is satisfied, the temperature detected by the second sensor is the defrosting end temperature. The defrosting operation is performed until the end temperature is reached, and if the selection condition is not satisfied, the temperature detected by the second sensor is the defrosting end temperature higher than the first defrosting end temperature. The defrosting operation is performed until the defrosting end temperature is reached.

When the cooling operation is performed by the control unit, the refrigerating cycle is controlled so that the air inside the refrigerator is cooled by the evaporator, and the inside temperature detected by the first sensor becomes the inside preset temperature. When the defrosting operation is performed by the control unit, the heating unit is controlled to heat the evaporator until the temperature detected by the second sensor reaches the defrosting end temperature. Here, if the amount of heating by the heating unit is excessive compared to the amount of frost formed on the evaporator, the power consumption associated with the energization of the heating unit will increase and the temperature inside the refrigerator will rise. problems such as an increase in In the past, the defrosting set temperature for judging the end of defrosting was changed based on the outside temperature detected by the outside temperature sensor. There was a possibility that an appropriate defrosting operation could not be performed according to the amount of frost formed.

In that respect, the control unit, if at least one selection condition selected from the first condition, the second condition, the third condition, and the fourth condition is satisfied, the temperature detected by the second sensor increases. The defrosting operation is performed until the first defrosting end temperature is reached, and if the selection condition is not satisfied, the temperature detected by the second sensor reaches the second defrosting end temperature higher than the first defrosting end temperature. Perform defrosting operation. Specifically, in the first condition, the number of times the door is opened and closed during the cooling operation is used as an index, and if the number of times the door is opened and closed is equal to or less than the reference number of times, the inflow of highly humid air outside the refrigerator into the refrigerator is suppressed. Therefore, it is estimated that the amount of frost on the evaporator is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the first condition is met, the amount of heating by the heating unit is less than the frost amount of the evaporator. It is possible to avoid excessive power consumption and reduce power consumption. In the second condition, the set temperature inside the refrigerator before the defrosting operation is used as an index. It is estimated that the amount of frost formation is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the second condition is met, the amount of heating by the heating unit is less than the amount of frost formed on the evaporator. It is possible to avoid excessive power consumption and reduce power consumption. In the third condition, the difference between the inside temperature before the defrosting operation and the inside temperature setting is used as an index. It can be said that the efficiency has not decreased so much, and it is presumed that the frost amount of the evaporator is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the third condition is met, the amount of heating by the heating unit is less than the frost amount of the evaporator. It is possible to avoid excessive power consumption and reduce power consumption. In the fourth condition, the temperature at or near the evaporator before the defrosting operation is used as an index. It is estimated that the amount of frost formation is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the fourth condition is met, the amount of heating by the heating unit is less than the frost amount of the evaporator. It is possible to avoid excessive power consumption and reduce power consumption. As described above, if the defrosting end temperature is varied based on whether or not at least one selection condition selected from among the first condition, the second condition, the third condition, and the fourth condition is satisfied, Since the appropriate defrosting operation can be performed according to the amount of frost formed on the evaporator, power consumption can be reduced.

(2) In addition to the above (1), the cooling storage is configured such that, when the defrosting operation is performed, the control unit controls at least the first condition, the second condition, the third condition and the fourth condition. Either the first defrosting end temperature or the second defrosting end temperature may be selected as the defrosting end temperature based on whether or not all of the conditions are satisfied. When all of the first, second, third, and fourth conditions are satisfied, it can be said that the degree of frost formation on the evaporator is extremely high. Therefore, the temperature detected by the second sensor becomes the first defrosting end temperature lower than the second defrosting end temperature only when all of the first, second, third and fourth conditions are satisfied. If the defrosting operation is performed by the control unit until the defrosting operation is performed, the certainty of avoiding excessive heating by the heating unit compared to the frost amount of the evaporator becomes extremely high, and power consumption can be reduced. can be done. In other words, the degree of certainty that the defrosting operation can be avoided by the control unit until the temperature detected by the second sensor reaches the first defrosting end temperature is increased, even though the frost amount is large. A situation in which the evaporator freezes due to insufficient defrosting and a situation in which the cooling performance of the refrigerating cycle deteriorates is less likely to occur.

(3) In addition to (1) or (2) above, the cooling storage may be configured such that, when the defrosting operation is performed, the controller controls the defrosting operation based on whether or not at least the first condition is satisfied. Selecting which one of the first defrosting end temperature and the second defrosting end temperature is to be used as the frost end temperature, and the inside temperature detected by the first sensor at a set time during the cooling operation. is equal to or higher than the door opening/closing detection temperature, the first condition may be that the number of times is equal to or less than a reference number of times. In the first condition, the frequency of opening and closing the door during cooling operation is used as an index. If the frequency of opening and closing the door is low, the inflow of highly humid air outside the refrigerator into the refrigerator is suppressed, so the evaporator frosts. The amount is estimated to be small. Therefore, by varying the defrosting end temperature based on whether the first condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. Further, conventionally, if the door is opened and closed even once during the cooling operation, the defrosting operation is performed until the temperature detected by the second sensor reaches the second defrosting end temperature. By varying the defrosting end temperature based on whether or not the first condition with the opening/closing frequency as an index is satisfied, power consumption can be reduced more appropriately. In addition, since the first sensor that detects the internal temperature is used to detect the opening and closing of the door, there is no need to install such a switch compared to the case where a switch is installed on the door to detect the opening and closing. becomes.

(4) Further, in addition to any one of (1) to (3) above, the cooling storage is based on whether or not at least the third condition is satisfied when the defrosting operation is performed. to select which of the first defrosting end temperature and the second defrosting end temperature to use as the defrosting end temperature, and at least at a set time immediately before the defrosting operation, the first sensor detects The third condition may be that the difference between the temperature inside the refrigerator and the set temperature inside the refrigerator is equal to or less than a reference value. The third condition uses the difference between the inside temperature and the inside preset temperature at the set time immediately before the defrosting operation as an index. As a result, whether or not the heat exchange efficiency of the refrigeration cycle is reduced due to frost formation on the evaporator immediately before the defrosting operation is performed depends on the difference between the internal temperature and the internal set temperature. will be reflected accurately. Therefore, by varying the defrosting end temperature based on whether the third condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator.

(5) Further, in addition to any one of (1) to (4) above, the cooling storage is based on whether or not at least the fourth condition is satisfied when the defrosting operation is performed. to select which of the first defrosting end temperature and the second defrosting end temperature to use as the defrosting end temperature, and to select the temperature detected by the second sensor at a set time immediately before the defrosting operation. The fourth condition may be that the temperature at which the defrosting is performed is equal to or higher than the reference defrosting temperature. The fourth condition uses the temperature at or near the evaporator at a set time immediately before the defrosting operation as an index. As a result, whether the amount of frost formed on the evaporator is large due to a drop in the temperature of the evaporator immediately before the defrosting operation is accurately reflected in the temperature of the evaporator or its vicinity. become. Therefore, by varying the defrosting end temperature based on whether the fourth condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator.

(6) In addition to any one of (1) to (5) above, the cooling storage is detected by the first sensor during the cooling operation in addition to the selection condition. When the second condition is satisfied that the accumulated time during which the internal temperature is equal to or lower than the internal preset temperature is equal to or longer than the reference accumulated time, the temperature detected by the second sensor is the first defrosting end temperature. When the selection condition and the second condition are not satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the second defrosting end temperature may In the second condition, the cumulative time when the internal temperature is equal to or lower than the internal temperature is used as an index. It can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator, and therefore the amount of frost formation on the evaporator is estimated to be small. Therefore, by varying the defrosting end temperature based on whether or not the second condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(7) Further, in addition to any one of (1) to (6) above, the cooling storage includes a compressor that forms the refrigeration cycle together with the evaporator, and the control unit controls the selection condition In addition, if the third condition is satisfied that the number of times the compressor is stopped due to the internal temperature being equal to or lower than the internal set temperature during the cooling operation is equal to or greater than the reference number of times, The defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature, and if the selection condition and the third condition are not satisfied, the temperature detected by the second sensor The defrosting operation may be performed until the temperature reaches the second defrosting end temperature. In the third condition, the number of times the compressor that constitutes the refrigeration cycle is stopped is used as an index. It can be said that the heat exchange efficiency of the refrigeration cycle has not decreased significantly due to frost formation on the evaporator, and it is estimated that the amount of frost formation on the evaporator is small. be. Therefore, by varying the defrosting end temperature based on whether or not the third condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(8) Further, in addition to any one of (1) to (7) above, the cooling storage includes a compressor that forms the refrigeration cycle together with the evaporator, and the control unit controls the selection condition In addition, if the fourth condition is satisfied that the integrated stop time of the compressor is equal to or greater than the reference stop time due to the internal temperature being equal to or lower than the internal set temperature during the cooling operation, The defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature, and if the selection condition and the fourth condition are not satisfied, the temperature detected by the second sensor The defrosting operation may be performed until the temperature reaches the second defrosting end temperature. In the fourth condition, the accumulated stop time of the compressor is used as an index, and if the accumulated stop time of the compressor during cooling operation is equal to or longer than the reference stop time, the cooling performance of the refrigeration cycle is is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator, so the amount of frost formation on the evaporator is small. It is estimated to be. Therefore, by varying the defrosting end temperature based on whether or not the fourth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(9) Further, in addition to any one of (1) to (8) above, the cooling storage includes a compressor that constitutes the refrigeration cycle together with the evaporator, and the control unit controls the selection condition In addition, when the average rotation speed of the compressor during the cooling operation satisfies the fifth condition that the reference rotation speed or less is satisfied, the temperature detected by the second sensor is the first defrost end temperature When the selection condition and the fifth condition are not satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the second defrosting end temperature may In the fifth condition, the average rotation speed of the compressor is used as an index. is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator, so the amount of frost formation on the evaporator is small. It is estimated to be. Therefore, by varying the defrosting end temperature based on whether or not the fifth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(10) In addition to any one of (1) to (9) above, the cooling storage includes a compressor that forms the refrigeration cycle together with the evaporator, and the control unit controls the selection condition In addition, when the average current value or power value of the compressor during the cooling operation satisfies a sixth condition that is equal to or less than the reference value, the temperature detected by the second sensor reaches the end of the first defrost The defrosting operation is performed until the temperature is reached, and if the selection condition and the sixth condition are not satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the second defrosting end temperature. may be performed. In the sixth condition, the average current value or power value of the compressor is used as an index, and if the average current value or power value of the compressor is below the reference value during cooling operation, It can be said that the cooling performance of the refrigerating cycle is properly demonstrated and the inside of the refrigerator is properly cooled, and the heat exchange efficiency of the refrigerating cycle has not decreased so much due to frost formation on the evaporator. It is estimated that the frost amount is small. Therefore, by varying the defrosting end temperature based on whether or not the sixth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(11) In addition to any one of (1) to (10) above, the cooling storage includes an internal fan arranged in the storage main body to circulate air in the storage, and the control A seventh step in which, in addition to the selection condition, the integrated stop time of the internal fan is equal to or greater than a reference stop time due to the fact that the internal temperature is equal to or lower than the internal set temperature during the cooling operation. When the conditions are satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature. The defrosting operation may be performed until the temperature detected by the second sensor reaches the second defrosting end temperature. In the seventh condition, the accumulated stop time of the internal fan is used as an index, and if the accumulated stop time of the internal fan during the cooling operation is equal to or longer than the standard stop time, the refrigeration cycle is The cooling performance of the evaporator is properly demonstrated and the inside of the refrigerator is properly cooled. The amount is estimated to be small. Therefore, by varying the defrosting end temperature based on whether or not the seventh condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(12) In addition to any one of (1) to (11) above, the cooling storage includes a compressor that forms the refrigeration cycle together with the evaporator, and a and an internal fan for circulating air, wherein the control unit operates the internal fan at high speed while the compressor is operating, and operates the internal fan while the compressor is stopped. is operated at a low speed, and the operation of the internal fan is stopped during the defrosting operation, and in addition to the selection condition, the cumulative low speed operation time of the internal fan during the cooling operation is equal to or greater than the reference operation time. When the eighth condition is satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature, and when the selection condition and the eighth condition are not satisfied The defrosting operation may be performed until the temperature detected by the second sensor reaches the second defrosting end temperature. In the eighth condition, the integrated low-speed operating time of the internal fan whose operating speed is controlled in synchronization with the operating state of the compressor is used as an index, and the integrated low-speed operating time of the internal fan during the cooling operation is the reference operating time. If it is above, it means that the cooling performance of the refrigeration cycle is properly demonstrated and the inside of the refrigerator is properly cooled even if the compressor and the inside fan are in low operation. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost on the evaporator is small. Therefore, by varying the defrosting end temperature based on whether or not the eighth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(13) In addition to any one of (1) to (12) above, the cooling storage includes an internal fan arranged in the storage main body to circulate the air in the storage, and the control part, in addition to the selection condition, if the average current value or power value of the internal fan during the cooling operation satisfies a ninth condition that is equal to or less than a reference value, the temperature detected by the second sensor is the first defrosting end temperature, and if the selection condition and the ninth condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature The defrosting operation may be performed until In the ninth condition, the average current value or power value of the internal fan is used as an index, and if the average current value or power value of the internal fan during cooling operation is equal to or less than the reference value, the internal fan is operating at a low level. Even if there is, the cooling performance of the refrigeration cycle is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator. It is estimated that the amount of frost on the evaporator is small. Therefore, by varying the defrosting end temperature based on whether or not the ninth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(14) In addition to any one of (1) to (13) above, the cooling storage includes a condenser that constitutes the refrigeration cycle together with the evaporator, a condenser fan that blows air to the condenser, wherein, in addition to the selection conditions, the control unit satisfies a tenth condition that the accumulated stop time of the condenser fan during the cooling operation is equal to or longer than the reference stop time, the second sensor The defrosting operation is performed until the temperature detected by is equal to the first defrosting end temperature, and when the selection condition and the tenth condition are not satisfied, the temperature detected by the second sensor is the first 2 The defrosting operation may be performed until the defrosting end temperature is reached. In the tenth condition, the accumulated stop time of the condenser fan that blows air to the condenser is used as an index, and if the accumulated stop time of the condenser fan during cooling operation is equal to or longer than the reference stop time, the condenser fan is operating at a low level. Even if there is, the cooling performance of the refrigeration cycle is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator. It is estimated that the amount of frost on the evaporator is small. Therefore, by varying the defrosting end temperature based on whether or not the tenth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(15) In addition to any one of (1) to (14) above, the cooling storage includes a condenser that constitutes the refrigeration cycle together with the evaporator, a condenser fan that blows air to the condenser, wherein, in addition to the selection condition, the control unit satisfies an eleventh condition that the average current value or power value of the condenser fan is equal to or less than a reference value during the cooling operation, the second The defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature, and when the selection condition and the eleventh condition are not satisfied, the temperature detected by the second sensor is The defrosting operation may be performed until the temperature reaches the second defrosting end temperature. The eleventh condition uses the average current value or power value of the condenser fan as an index. Even if there is, the cooling performance of the refrigeration cycle is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the evaporator. It is estimated that the amount of frost on the evaporator is small. Therefore, by varying the defrosting end temperature based on whether or not the eleventh condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

(16) In addition to any one of (1) to (15) above, the cooling storage includes a compressor that forms the refrigeration cycle together with the evaporator, and the refrigeration cycle together with the evaporator and the compressor. a condenser, a condenser fan that blows air to the condenser, and a third sensor that detects the temperature of the condenser or the vicinity of the condenser, and the control unit satisfies the selection condition In addition, when the accumulated time during which the temperature detected by the third sensor is lower than the reference temperature during the cooling operation satisfies a twelfth condition that the temperature is equal to or longer than the reference accumulated time, the temperature detected by the second sensor is satisfied. The defrosting operation is performed until the temperature detected by the second defrosting end temperature reaches the first defrosting end temperature, and if the selection condition and the twelfth condition are not satisfied, the temperature detected by the second sensor is the second defrosting The defrosting operation may be performed until the end temperature is reached. In the twelfth condition, the integrated time during which the temperature detected by the third sensor during the cooling operation becomes lower than the reference temperature is used as an index. The cooling performance of the refrigeration cycle is adequately demonstrated even when the machine is operating at low speed, and the inside of the refrigerator is properly cooled. Therefore, it is estimated that the amount of frost on the evaporator is small. Therefore, by varying the defrosting end temperature based on whether or not the twelfth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the evaporator. .

According to the technique described in this specification, it is possible to reduce power consumption.

Front view of the freezer according to Embodiment 1 Diagram showing the internal structure of the refrigerator viewed from the right side Block diagram showing the electrical configuration of the freezer Timing chart showing the cooling operation and defrosting operation of the freezer and the first condition as the selection condition Timing chart showing the cooling operation and defrosting operation of the freezer and the second condition as the selection condition Timing chart showing the cooling operation and defrosting operation of the freezer and the third condition as the selection condition Timing chart showing the cooling operation and defrosting operation of the freezer and the fourth condition as the selection condition Timing chart showing the cooling operation and defrosting operation of the freezer when all of the first, second, third and fourth conditions are selected conditions A timing chart showing the cooling operation and the defrosting operation of the freezer according to the second embodiment and explaining the first condition. A timing chart showing the cooling operation and the defrosting operation of the freezer according to the third embodiment and explaining the fourth condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the fourth embodiment and explaining the second condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the fifth embodiment and explaining the third condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the sixth embodiment and explaining the fourth condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the seventh embodiment and explaining the fifth condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the eighth embodiment and explaining the sixth condition. A timing chart showing the cooling operation and the defrosting operation of the freezer according to the ninth embodiment and explaining the seventh condition A timing chart showing the cooling operation and defrosting operation of the freezer according to the tenth embodiment and for explaining the eighth condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the eleventh embodiment and for explaining the ninth condition A timing chart showing the cooling operation and the defrosting operation of the freezer according to the twelfth embodiment and explaining the tenth condition Timing chart for explaining the eleventh condition showing the cooling operation and the defrosting operation of the freezer according to the thirteenth embodiment A timing chart showing the cooling operation and the defrosting operation of the freezer according to the fourteenth embodiment and explaining the twelfth condition

<Embodiment 1>
In Embodiment 1, a four-door freezer 10 will be described as an example of a cooling storage with reference to FIGS. 1 to 8. FIG. The freezer 10 includes a storage body 12, a door 14, a machine room 16, and a cooling device 18, as shown in FIGS. The cooling device 18 is a device for cooling the inside of the storage body 12 and includes a compressor 22 , a condenser 26 having a condenser fan 24 , and a cooler (evaporator) 28 . 1 and 2 show reference arrows in the vertical direction and the horizontal direction, the upper side is denoted as "U", the lower side is denoted as "D", and the right side is denoted as "R". , and the left side is indicated as "L".

As shown in FIG. 2, the storage body 12 is a heat-insulating box body having an opening 12A that opens forward, and is constructed by foaming and filling a space between an outer box 30 and an inner box 32 with a heat-insulating material. A storage chamber 34 and a cooler chamber 36 are provided inside the storage body 12 (that is, inside the inner box 32). A plurality of shelves on which objects to be stored such as foodstuffs are placed are provided in the storage chamber 34 , and a cooler 28 is accommodated in the cooler chamber 36 . The storage compartment 34 and cooler compartment 36 are separated by a cooling duct 40 .

The cooling duct 40 has a sloped portion 42 that slopes downward toward the rear. The inclined portion 42 of the cooling duct 40 is provided with a front inlet 42A and a rear outlet 42B. An internal fan (circulation fan) 44 for circulating the air inside the refrigerator is provided above the suction port 42A in the cooler chamber 36 . Further, above the internal fan 44, an internal temperature sensor (first sensor) 46 for detecting the internal temperature is provided. The cooler 28 is arranged behind the internal fan 44 . The cooler 28 includes a defrost heater (defrost heater, heating unit) 27 capable of heating the cooler 28 during defrosting, and a defrost temperature sensor ( A second sensor 29 is attached. Specifically, the inside temperature sensor 46 and the defrosting temperature sensor 29 are temperature thermistors. A cooling duct 40 separates the storage chamber 34 and the cooler chamber 36 and receives defrosted water generated when the frost adhering to the cooler 28 is melted. An inclined portion 42 of the cooling duct 40 is connected to a discharge pipe 48 arranged behind the cooler 28 for discharging the defrosted water. The discharge pipe 48 penetrates the rear wall of the inner box 32 located behind the cooler chamber 36 and extends further downward.

Each device (compressor 22, condenser 26, and cooler 28) constituting the cooling device 18 is circulated and connected by refrigerant pipes to form a known refrigeration cycle (refrigeration circuit). The inside air of the storage chamber 34 is sucked into the cooler chamber 36 through the suction port 42A by the internal fan 44 . At this time, the inside air sucked by the inside fan 44 hits the inside temperature sensor 46, so that the temperature inside the storage chamber 34, that is, the inside temperature is detected. The inside air sucked by the internal fan 44 is cooled by the cooler 28 and discharged into the storage compartment 34 through the outlet 42B. As a result, the object stored in the storage chamber 34 is cooled.

When the cooling device 18 operates, water vapor around the cooler 28 is cooled by the cooler 28 and solidified, so that frost adheres to the surface of the cooler 28 . The frost adhering to the cooler 28 is melted when the freezer 10 starts defrosting operation (defrost operation). The defrosting operation is performed by a heater defrosting method in which the cooler 28 is heated by the defrosting heater 27 to melt the frost adhering to the cooler 28 . The frost melted by the defrosting operation falls on the inclined portion 42 of the cooling duct 40 and is discharged from the storage main body 12 through the discharge pipe 48 .

The door 14 is attached to the opening 12A of the storage body 12 so that it can be opened and closed. As shown in FIG. 1, the doors 14 are provided in pairs of two pairs on the left and right in a double-door manner. A door packing (sealing member) 15 is attached to the peripheral edge of the rear surface (inside surface) of each door 14 so as to be in close contact with the opening edge of the opening 12A of the storage body 12 .

The machine room 16 is provided above the storage body 12, as shown in FIGS. The machine room 16 accommodates a compressor 22 and a condenser 26 as shown in FIG. The compressor 22 is located in the rear of the machine room 16 while the condenser 26 is located in the front of the machine room 16 with the condenser fan 24 . Condenser fan 24 is mounted rearwardly with respect to condenser 26 . A filter is provided in front of the condenser 26 to prevent dust in the air from adhering to the condenser 26 and condensing ability from deteriorating. If dust adheres to the filter and clogs it, even if the condenser fan 24 rotates, sufficient heat cannot be exchanged between the condenser 26 and the outside air, which may reduce the cooling efficiency. Therefore, a clogging temperature sensor (third sensor) 25 is attached to the piping of the condenser 26 via a holder in order to detect clogging of the filter. The clogging temperature sensor 25 is specifically a temperature thermistor and can detect the temperature of the condenser 26 or the vicinity of the condenser 26 . Since the temperature of the condenser 26 or the vicinity of the condenser 26 fluctuates according to the amount of dust adhering to the filter, the temperature detected by the clogging temperature sensor 25 is used to detect whether or not the filter is clogged. is possible. Further, the temperature detected by the clogging temperature sensor 25 while the cooling operation (operation of the compressor 22 and the like) is stopped is equivalent to the outside air temperature. Therefore, the clogging temperature sensor 25 can also detect the outside air temperature.

As shown in FIG. 1, the machine room 16 accommodates an electrical box 50 and an operation box 52 . An opening is provided in a part of the front surface of the machine room 16, and the front surface of the operation box 52 is exposed to the outside through the opening. A display screen 54 and a plurality of operation buttons 56 (an example of an operation unit) are provided on the front surface of the operation box 52 . Information such as the internal temperature of the storage chamber 34 is displayed on the display screen 54 . Each operation button 56 is a button for changing the setting of the freezer 10 (for example, the set temperature in the storage chamber 34, that is, the set temperature inside the freezer) or the like by the user's operation. The electrical box 50 accommodates a microcomputer in which a CPU, a RAM, and the like are integrated into one chip, a control board including a ROM, and the like.

The freezer 10 is provided with a controller 20 that electrically controls various devices. The control unit 20 is configured by a control board inside the electrical box 50 . A control board in the electrical box 50 is electrically connected to various devices. The control unit 20 controls the cooling operation, defrosting operation, etc. (controlling the compressor 22, the condenser fan 24, the internal fan 44, the defrosting heater 27, etc.).

Specifically, as shown in FIG. and the in-chamber temperature sensor 46 are electrically connected. The control unit 20 performs a cooling operation by controlling the compressor 22, the condenser fan 24, and the internal fan 44 that constitute the refrigeration cycle. During the cooling operation, the controller 20 operates the compressor 22, the condenser fan 24, and the internal fan 44, but stops the defrosting heater 27 (see FIG. 4). The control unit 20 performs defrosting operation by controlling the defrosting heater 27 . While the defrosting operation is performed, the control unit 20 operates the defrosting heater 27 while stopping all of the compressor 22, the condenser fan 24 and the internal fan 44 (see FIG. 4). Specifically, when the defrosting operation is started, the control unit 20 stops the compressor 22, the condenser fan 24, and the internal fan 44, operates the defrosting heater 27, and defrosts after a predetermined time has passed. Until the heater 27 is stopped and the defrosting operation is finished, it waits to promote the removal of the water adhering to the cooler 28.例文帳に追加The waiting time from when the defrosting heater 27 is stopped until when the next cooling operation is started is the draining time. The control unit 20 performs a cooling operation, a defrosting operation, etc., based on the operation performed on the operation button 56 of the operation box 52 and the temperatures detected by the clogging temperature sensor 25, the defrosting temperature sensor 29, and the inside temperature sensor 46, respectively. I do.

Specifically, the control unit 20 performs the cooling operation so that the internal temperature detected by the internal temperature sensor 46 becomes the internal preset temperature set according to the operation of the operation button 56 . For example, even during the cooling operation, the user can appropriately change the preset internal temperature by operating the operation button 56 . After continuing the above-described cooling operation for, for example, 6 hours, the control unit 20 performs the defrosting operation until the temperature detected by the defrosting temperature sensor 29 reaches the defrosting end temperature. After performing the above-described defrosting operation, the control unit 20 repeats the cycle of performing the cooling operation again for, for example, 6 hours, and then performing the defrosting operation again.

The control unit 20 can detect the opening/closing of the door 14 when the internal temperature detected by the internal temperature sensor 46 is equal to or higher than a predetermined door open/close detection temperature. This is based on the fact that when the door 14 is opened and closed, outside air flows into the refrigerator and the temperature inside the refrigerator rises. If the internal temperature detected by the internal temperature sensor 46 during the cooling operation never exceeds the door opening/closing detection temperature, the control unit 20 controls the defrosting scheduled to be performed after the cooling operation ends. You can cancel driving. If the door 14 is never opened/closed during the cooling operation, there is no inflow of outside air due to the opening/closing of the door 14. Therefore, frost formation on the cooler 28 is sufficiently suppressed, and even if the defrosting operation is cancelled, It can be said that deterioration of cooling performance due to frost is unlikely to occur. If the defrosting operation is canceled, it is possible to avoid an increase in the temperature inside the refrigerator due to the execution of the defrosting operation, thereby reducing the power consumption required for the cooling operation. When the defrosting operation is canceled as described above, the control unit 20 starts the next cooling operation following the end of the previous cooling operation. When the above-described defrosting operation is canceled twice in succession, the control unit 20 always performs the next defrosting operation. That is, when the defrosting operation is canceled twice in succession and the cooling operation is performed three times in succession (for example, 18 hours), the control unit 20 does not open or close the door 14 even once during the three cooling operations. To execute the next scheduled defrosting operation without canceling it even if there is no defrosting operation. As a result, even if a certain amount of frost occurs on the cooler 28 as the cooling operation continues for a long period of time, the cooler 28 can be defrosted appropriately by performing the defrosting operation. In addition, when the temperature detected by the clogging temperature sensor 25 reaches a predetermined clogging detection temperature, the control unit 20 can display a prompt to clean the filter on the display screen 54 .

By the way, if the heating by the defrosting heater 27 in the defrosting operation is excessive compared to the amount of frost formed on the cooler 28, the amount of power consumption associated with the energization of the defrosting heater 27 increases and the temperature inside the refrigerator rises. In addition to the problem that the amount of power consumed in the cooling operation increases, the problem that the quality of the objects stored in the storage chamber 34 deteriorates occurs. Conventionally, the defrosting set temperature for judging the completion of defrosting was varied based on the outside temperature detected by the outside temperature sensor. , there is a possibility that an appropriate defrosting operation cannot be performed according to the actual frost amount.

Therefore, the control unit 20 according to the present embodiment satisfies at least one selection condition selected from the following first condition, second condition, third condition, and fourth condition, based on whether or not the condition is satisfied. The defrosting end temperature shall be changed. The first condition among the four conditions is that the number of times the internal temperature detected by the internal temperature sensor 46 during the cooling operation exceeds the door open/close detection temperature is equal to or less than a preset reference number of times. (see FIG. 4). The second condition is that the set temperature inside the refrigerator is equal to or higher than a preset reference set temperature during the cooling operation (see FIG. 5). The third condition is that the difference between the internal temperature detected by the internal temperature sensor 46 and the internal preset temperature during the cooling operation is equal to or less than a preset reference value (see FIG. 6). ). The fourth condition is that the temperature detected by the defrosting temperature sensor 29 during the cooling operation is equal to or higher than a preset reference defrosting temperature (see FIG. 7). When at least one selection condition selected from these four conditions is satisfied, the control unit 20 determines that the temperature detected by the defrosting temperature sensor 29 is the defrosting end temperature, which is the first defrosting end temperature (for example, Defrost operation is performed until the temperature reaches 3°C. On the other hand, when at least one selection condition selected from the four conditions described above is not satisfied, the control unit 20 determines that the temperature detected by the defrosting temperature sensor 29 is higher than the first defrosting end temperature. The defrosting operation is performed until the second defrosting end temperature (for example, 20° C.), which is a high defrosting end temperature, is reached.

In the above-described first condition, the index is the number of openings and closings of the door 14 detected based on the internal temperature detected by the internal temperature sensor 46 during the cooling operation performed before the defrosting operation. If the number of times is equal to or less than the reference number of times (for example, once), it is estimated that the amount of frost on the cooler 28 is small because the inflow of air with high humidity outside the refrigerator is suppressed. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the first condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. On the other hand, when the first condition is not satisfied, air with high humidity outside the chamber flows into the chamber more than when the first condition is satisfied, and the amount of frost formed on the cooler 28 is large. Since it is estimated, if the defrosting operation is performed until the second defrosting end temperature higher than the first defrosting end temperature, the heating by the defrosting heater 27 is commensurate with the frost amount of the cooler 28. will be sufficient. As a result, the frost adhering to the cooler 28 can be sufficiently removed, so that freezing of the cooler 28 and deterioration of cooling performance related to the refrigeration cycle due to remaining frost can be prevented. can be avoided.

In the above-described second condition, the internal set temperature during the cooling operation performed before the defrosting operation is used as an index, and if the internal set temperature is equal to or higher than the reference set temperature (eg -22°C), the refrigeration cycle is low. Since the operation is sufficient, it is presumed that the temperature of the cooler 28 does not drop so much and the amount of frost formation is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the second condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. On the other hand, when the second condition is not satisfied, the refrigerating cycle is operated at a higher rate than when the second condition is satisfied, the temperature of the cooler 28 is lowered, and the amount of frost formed on the cooler 28 is large. Since it is estimated, if the defrosting operation is performed until the second defrosting end temperature higher than the first defrosting end temperature, the heating by the defrosting heater 27 is commensurate with the frost amount of the cooler 28. will be sufficient. As a result, the frost adhering to the cooler 28 can be sufficiently removed, so that freezing of the cooler 28 and deterioration of cooling performance related to the refrigeration cycle due to residual frost can be prevented. can be avoided.

In the third condition described above, the difference between the temperature inside the refrigerator during the cooling operation performed before the defrosting operation and the preset temperature inside the refrigerator is used as an index, and if the difference is a reference value (for example, 1 K (Kelvin)) or less , it can be said that the heat exchange efficiency of the refrigerating cycle has not decreased so much due to frost formation on the cooler 28, and it is presumed that the amount of frost formation on the cooler 28 is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the third condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. On the other hand, when the third condition is not satisfied, the heat exchange efficiency of the refrigerating cycle is lowered due to frost formation on the cooler 28 compared to the case where the third condition is satisfied, and the frost formation on the cooler 28 is reduced. Since the amount is estimated to be large, if the defrosting operation is performed until the second defrosting end temperature higher than the first defrosting end temperature is reached, the heating by the defrosting heater 27 will cause the cooler 28 to cool down. It will be sufficient for the amount of frost. As a result, the frost adhering to the cooler 28 can be sufficiently removed, so that freezing of the cooler 28 and deterioration of cooling performance related to the refrigeration cycle due to residual frost can be prevented. can be avoided.

In the above-described fourth condition, the temperature of the cooler 28 during the cooling operation performed before the defrosting operation or the temperature in the vicinity thereof is used as an index, and if the temperature is higher than the reference defrosting temperature (eg -28 ° C.), cooling It is presumed that the temperature of the cooler 28 is not so low, and therefore the amount of frost on the cooler 28 is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the fourth condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. On the other hand, when the fourth condition is not satisfied, the temperature of the cooler 28 is lower than when the fourth condition is satisfied, and it is estimated that the amount of frost formed on the cooler 28 is large. If the defrosting operation is performed until the second defrosting end temperature, which is higher than the first defrosting end temperature, the heating by the defrosting heater 27 becomes sufficient for the amount of frost formed on the cooler 28 . As a result, the frost adhering to the cooler 28 can be sufficiently removed, so that freezing of the cooler 28 and deterioration of cooling performance related to the refrigeration cycle due to residual frost can be prevented. can be avoided.

As described above, if the defrosting end temperature is varied based on whether or not at least one selection condition selected from the first to fourth conditions is satisfied, the frost amount of the cooler 28 Since an appropriate defrosting operation can be performed according to the conditions, the amount of power consumption can be reduced, and the frost adhering to the cooler 28 can be sufficiently removed.

Next, the control when each of the first condition, the second condition, the third condition, and the fourth condition is set as the selection condition will be sequentially described with reference to FIGS. 4 to 7. FIG. 4 to 7, the operating state of the compressor 22, the condenser fan 24, the internal fan 44, and the defrosting heater 27 is indicated as ON, and the stopped state is indicated as OFF. 4 to 7 show changes in temperature detected by each of the internal temperature sensor 46 and the defrosting temperature sensor 29, and the defrosting temperature sensor 29 detects the first defrosting detection temperature and the second defrosting temperature. The defrosting detection temperature is also shown. In FIGS. 5 and 6, transitions of the internal chamber set temperature are shown. In FIG. 6, the difference between the inside temperature detected by the inside temperature sensor 46 and the inside preset temperature is indicated as "temperature difference", and its reference value is also indicated. Moreover, in FIGS. 4-7, the draining time is written as "draining."

First, the control when the first condition is the selection condition will be described in detail with reference to FIG. First, in the first condition according to the present embodiment, the internal temperature detected by the internal temperature sensor 46 is equal to or higher than the door opening/closing detection temperature during the set time during which the cooling operation is performed immediately before the defrosting operation. The number of times, that is, the frequency of opening and closing the door 14 is used as an index. Specifically, as shown in FIG. 4, the control unit 20 divides the time (for example, 6 hours) during which the cooling operation is performed into a plurality (for example, 24), and divides each set time (for example, 15 minutes each). , the number of times the internal temperature detected by the internal temperature sensor 46 exceeds the door opening/closing detection temperature is detected. The control unit 20 counts the number of times the door 14 has been opened and closed based on the internal temperature detected by the internal temperature sensor 46 during the 15-minute segmented set time, and uses the counted number of times as the reference number of times. Compare with The control unit 20 repeats the operation (routine) of counting the number of times the door 14 is opened and closed as described above and comparing it with the reference number of times 24 times during the cooling operation. Defrosting detection temperature is determined based on whether or not is even once. Note that the set time may always be the elapsed time after the door 14 is opened once, and the first time may be counted as one time.

For example, the first cooling operation (left side of FIG. 4) shown in FIG. is also increasing. In this case, the control unit 20 determines that the first condition is not satisfied. The defrosting heater 27 heats the cooler 28 until the detected temperature (defrosting temperature) reaches 20° C., which is the second defrosting end temperature. In FIG. 4, the defrosting operation in which the defrosting end temperature is set to the second defrosting end temperature is indicated as "normal defrosting operation", and the same applies to FIGS. 5 to 8 below. On the other hand, the second cooling operation shown in FIG. 4 (the right side of FIG. 4) does not include the case where the number of times the door 14 is opened and closed within the set time is two or more times, and the number of times the door 14 is opened and closed is one time, which is the same as the reference number of times. Only cases that are In this case, the control unit 20 determines that the first condition is satisfied, and in the second (right side of FIG. 4) defrosting operation following the second cooling operation, the defrosting temperature sensor 29 The defrosting heater 27 heats the cooler 28 until the detected temperature reaches 3° C., which is the first defrosting end temperature. In FIG. 4, the defrosting operation in which the defrosting end temperature is set to the first defrosting end temperature is described as "simple defrosting operation", and the same applies to FIGS. 5 to 8 below. The time required for the simple defrosting operation when the first condition is met and the time during which the defrosting heater 27 is energized in the simple defrosting operation are compared to the times in the normal defrosting operation when the first condition is not met. , are both shorter. The maximum internal temperature that rises as the simple defrosting operation is performed when the first condition is met rises as the normal defrosting operation is performed when the first condition is not met. It is lower than the maximum temperature inside the refrigerator.

Control when the second condition is the selection condition will be described in detail with reference to FIG. In the second condition according to the present embodiment, the set internal temperature during the cooling operation performed immediately before the defrosting operation is used as an index. Specifically, as shown in FIG. 5, the control unit 20 detects the internal set temperature that is set according to the operation of the operation button 56 while the cooling operation is being performed, and sets the internal set temperature to Compare with reference set temperature. For example, the operation time of the first cooling operation (left side of FIG. 5) shown in FIG. 5 partially includes the time during which the internal set temperature is set lower than the reference set temperature of −22° C. ing. In this case, the control unit 20 determines that the second condition is not satisfied. The defrosting heater 27 heats the cooler 28 until the detected temperature reaches 20° C., which is the second defrosting end temperature (normal defrosting operation). On the other hand, in the second cooling operation shown in FIG. 5 (the right side of FIG. 5), the internal set temperature continues to be higher than the reference set temperature of −22° C., and the internal set temperature is −22. It never drops below °C. In this case, the control unit 20 determines that the second condition is satisfied. The defrosting heater 27 heats the cooler 28 until the detected temperature reaches 3° C., which is the first defrosting end temperature (simple defrosting operation). The time required for the simple defrosting operation when the second condition is satisfied and the time during which the defrosting heater 27 is energized in the simple defrosting operation are compared to the times in the normal defrosting operation when the second condition is not satisfied. , are both shorter. Also, as in the case of the first condition (see FIG. 4), the maximum internal temperature that rises as the simple defrosting operation is performed when the second condition is satisfied satisfies the second condition. It is lower than the maximum internal temperature that rises as the normal defrosting operation is performed.

Control when the third condition is the selection condition will be described in detail with reference to FIG. In the third condition according to the present embodiment, the index is the difference between the internal temperature detected by the internal temperature sensor 46 and the internal preset temperature at the set time immediately before the defrosting operation. Specifically, as shown in FIG. 6, the controller 20 controls the control unit 20 for two hours immediately before the defrosting operation is started (from the time four hours have passed since the cooling operation is started until the defrosting operation is started). 2 hours) is set as the set time, and the internal temperature detected by the internal temperature sensor 46 and the internal set temperature set according to the operation of the operation button 56 are detected during the set time. and the temperature difference between them is calculated, and the calculated temperature difference is compared with a reference value. For example, at the set time in the first cooling operation (left side of FIG. 6) shown in FIG. 6, the temperature difference is always higher than the reference value of 1K and never lower than 1K. In this case, the control unit 20 determines that the third condition is not satisfied. The defrosting heater 27 heats the cooler 28 until the detected temperature reaches 20° C., which is the second defrosting end temperature (normal defrosting operation). On the other hand, the set time for the second cooling operation shown in FIG. 6 (on the right side of FIG. 6) includes the timing when the temperature difference becomes lower than 1K, which is the reference value. This is because the temperature difference between the inside temperature and the inside temperature setting became smaller as the inside temperature setting was changed to a higher temperature during the normal defrosting operation. Influencing. In this case, the control unit 20 determines that the third condition is satisfied. The cooler 28 is heated by the defrosting heater 27 until the detected temperature reaches 3° C., which is the first defrosting end temperature (simple defrosting operation). The time required for the simple defrosting operation when the third condition is met and the time during which the defrosting heater 27 is energized in the simple defrosting operation are compared to the times in the normal defrosting operation when the third condition is not met. , are both shorter. The maximum internal temperature that rises as the simple defrosting operation is performed when the third condition is met rises as the normal defrosting operation is performed when the third condition is not met. It is lower than the maximum temperature inside the refrigerator.

Control when the fourth condition is the selection condition will be described in detail with reference to FIG. The fourth condition according to the present embodiment uses the temperature detected by the defrosting temperature sensor 29 at the set time immediately before the defrosting operation as an index. Specifically, as shown in FIG. 7, the control unit 20 controls the control unit 15 for 15 minutes immediately before the defrosting operation is started (5 hours and 45 minutes after the cooling operation is started, the defrosting operation is started). 15 minutes until defrosting) is set as a set time, and the temperature detected by the defrosting temperature sensor 29 is detected and compared with the reference defrosting temperature during the set time. For example, the set time for the first cooling operation (the left side of FIG. 7) shown in FIG. 7 includes the timing when the temperature detected by the defrosting temperature sensor 29 becomes lower than the reference defrosting temperature of −28° C. is In this case, the control unit 20 determines that the fourth condition is not satisfied. The defrosting heater 27 heats the cooler 28 until the detected temperature reaches 20° C., which is the second defrosting end temperature (normal defrosting operation). On the other hand, during the set time in the second cooling operation (the right side of FIG. 7) shown in FIG. 7, the temperature detected by the defrosting temperature sensor 29 continues to be higher than the reference defrosting temperature of -28°C. and has never dropped below -28°C. In this case, the control unit 20 determines that the fourth condition is satisfied. The cooler 28 is heated by the defrosting heater 27 until the detected temperature reaches 3° C., which is the first defrosting end temperature (simple defrosting operation). The time required for the simple defrosting operation when the fourth condition is met and the time during which the defrosting heater 27 is energized in the simple defrosting operation are compared to the times in the normal defrosting operation when the fourth condition is not met. , are both shorter. Also, as in the case of the first condition (see FIG. 4), the maximum internal temperature that rises as the simple defrosting operation is performed when the fourth condition is satisfied satisfies the fourth condition. It is lower than the maximum internal temperature that rises as the normal defrosting operation is performed.

Next, the control when all of the first condition, second condition, third condition and fourth condition are used as selection conditions will be sequentially described with reference to FIG. The notation in FIG. 8 is the same as the notation in FIGS. As shown in FIG. 8, the control unit 20 selects different defrosting end temperatures based on whether or not all of the same first, second, third and fourth conditions as above are satisfied. For example, the first cooling operation (left side of FIG. 8) shown in FIG. In addition, the set temperature inside the refrigerator has been set lower than the reference set temperature of -22°C, and has never been set higher than -22°C. The temperature difference between the internal temperature and the internal set temperature is always higher than the reference value of 1K and never falls below 1K, and the temperature detected by the defrosting temperature sensor 29 is the reference value. It includes the timing when it becomes lower than the defrosting temperature of -28°C. In this case, the control unit 20 determines that all of the first condition, the second condition, the third condition, and the fourth condition are not satisfied. In the defrosting operation on the left side), the defrosting heater 27 heats the cooler 28 until the temperature (defrosting temperature) detected by the defrosting temperature sensor 29 reaches 20° C., which is the second defrosting end temperature. (normal defrosting operation). Any of the first, second, third and fourth conditions is not limited to the case where all of the first, second, third and fourth conditions are not satisfied as described above. Even if one condition, two conditions, or three conditions are not satisfied (if any three conditions, two conditions, or one condition is satisfied), the control unit 20 performs the above-described normal defrost do the driving.

On the other hand, the second cooling operation shown in FIG. 8 (on the right side of FIG. 8) does not include the case where the number of times the door 14 is opened and closed within the set time is two or more times, and the number of times the door 14 is opened and closed is one time, which is the same as the reference number of times. In addition, the set temperature inside the refrigerator is set higher than -22°C, which is the reference set temperature, and has never been set lower than -22°C. There is a timing when the temperature difference between the inside temperature and the inside preset temperature becomes lower than the reference value of 1K, and the temperature detected by the defrosting temperature sensor 29 is below the reference defrosting temperature of -28°C. The temperature continues to be high and has never dropped below -28°C. Note that the set internal temperature is changed to be higher than the reference set temperature of −22° C. during the first defrosting operation (normal defrosting operation). In this case, the control unit 20 determines that all of the first, second, third, and fourth conditions are satisfied, and the second cooling operation following the second cooling operation ( In the defrosting operation on the right side), the temperature detected by the defrosting temperature sensor 29 reaches 3° C., which is the first defrosting end temperature, until the defrosting heater 27 heats the cooler 28 (simple defrosting drive).

Thus, when all of the first, second, third, and fourth conditions are satisfied, it can be said that the degree of frost formation on the cooler 28 is extremely high. Therefore, if the simple defrosting operation described above is performed only when all of the first, second, third, and fourth conditions are satisfied, heating by the defrosting heater 27 causes frost formation on the cooler 28. The certainty of avoiding an excessive amount compared to the amount is extremely high, and it is possible to reduce the amount of power consumption. In other words, since the certainty that the simple defrosting operation can be avoided despite the large amount of frost formation is high, defrosting is insufficient and the cooler 28 freezes, or the refrigeration cycle is affected. This makes it difficult for the cooling performance to deteriorate. Further, the time required for the simple defrosting operation when all of the first condition, the second condition, the third condition, and the fourth condition are satisfied, and the time during which the defrosting heater 27 is energized in the simple defrosting operation are the first conditions. , 2nd condition, 3rd condition, and 4th condition When at least 1 (all are included) are not satisfy|filled, all are short compared with each time in the normal defrosting operation. Then, the maximum internal temperature that rises as the simple defrosting operation is performed when all of the first condition, the second condition, the third condition, and the fourth condition are satisfied is It is lower than the maximum internal temperature that rises as the normal defrosting operation is performed when at least one of the conditions, the third condition, and the fourth condition is not satisfied.

In addition, it is not limited to the case where all of the first, second, third and fourth conditions are set as the selection conditions. For example, any of the first, second, third and fourth conditions It is also possible to set three or two as a selection condition.

As described above, the freezer (cooling storage) 10 of the present embodiment includes a storage body 12 having an opening 12A, a door 14 for opening and closing the opening 12A, an internal temperature sensor 46 for detecting internal temperature, and a refrigerating cycle. a cooler (evaporator) 28, a defrosting heater (heating unit) 27 that heats the cooler 28, a defrosting temperature sensor 29 that detects the temperature of the cooler 28 or the vicinity of the cooler 28, and the interior The cooling operation is performed by controlling the refrigerating cycle so that the internal temperature detected by the temperature sensor 46 becomes the internal preset temperature, and the defrosting heater 27 is controlled to defrost the temperature detected by the defrosting temperature sensor 29. and a control unit 20 for performing defrosting operation until the end temperature is reached. A first condition that the number of times the internal temperature detected by the internal temperature sensor 46 during the cooling operation exceeds the door open/close detection temperature is equal to or less than the reference number of times, and A second condition that the internal set temperature is equal to or higher than the reference set temperature, and a third condition that the difference between the internal temperature detected by the internal temperature sensor 46 and the internal set temperature during the cooling operation is equal to or less than the reference value. , the fourth condition that the temperature detected by the defrosting temperature sensor 29 during the cooling operation is equal to or higher than the reference defrosting temperature, and if at least one selection condition is satisfied, the defrosting temperature sensor 29 The defrosting operation is performed until the detected temperature reaches the first defrosting end temperature, which is the defrosting end temperature. If the selection condition is not satisfied, the temperature detected by the defrosting temperature sensor 29 reaches the first defrosting end temperature. The defrosting operation is performed until the second defrosting end temperature, which is the defrosting end temperature higher than the temperature, is reached.

When the cooling operation is performed by the control unit 20, the refrigerating cycle is controlled so that the air inside the refrigerator is cooled by the cooler 28, and the inside temperature detected by the inside temperature sensor 46 becomes equal to the inside preset temperature. Become. When the defrosting operation is performed by the controller 20, the defrosting heater 27 is controlled to heat the cooler 28 until the temperature detected by the defrosting temperature sensor 29 reaches the defrosting end temperature. Here, if the heating by the defrost heater 27 is excessive compared to the amount of frost formed on the cooler 28, the power consumption related to the energization of the defrost heater 27 increases and the temperature inside the refrigerator rises. problems such as an increase in power consumption in Conventionally, the defrosting set temperature for judging the completion of defrosting was varied based on the outside temperature detected by the outside temperature sensor. , there is a possibility that an appropriate defrosting operation cannot be performed according to the actual frost amount.

In that respect, the controller 20 detects the temperature detected by the defrosting temperature sensor 29 when at least one selection condition selected from the first condition, the second condition, the third condition, and the fourth condition is satisfied. The defrosting operation is performed until the temperature detected by the defrosting temperature reaches the first defrosting end temperature, and if the selection condition is not satisfied, the second defrosting temperature detected by the defrosting temperature sensor 29 is higher than the first defrosting end temperature. Defrost operation is performed until the end temperature is reached. Specifically, in the first condition, the number of times the door 14 is opened and closed during the cooling operation is used as an index. Therefore, it is estimated that the amount of frost on the cooler 28 is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the first condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. In the second condition, the internal preset temperature before the defrosting operation is used as an index. It is estimated that the amount of frost formation is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the second condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. In the third condition, the difference between the inside temperature before the defrosting operation and the inside temperature setting is used as an index. It can be said that the exchange efficiency has not decreased so much, and it is presumed that the amount of frost on the cooler 28 is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached in the case of the third condition, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. In the fourth condition, the temperature of the cooler 28 before the defrosting operation or the temperature in the vicinity thereof is used as an index, and if the temperature is equal to or higher than the reference defrosting temperature, the temperature of the cooler 28 is not so low. It is estimated that the amount of frost on the cooler 28 is small. Therefore, if the defrosting operation is performed until the first defrosting end temperature lower than the second defrosting end temperature is reached when the fourth condition is satisfied, the heating by the defrosting heater 27 causes the cooler 28 to frost. It is possible to avoid becoming excessive compared to the amount, and to reduce the amount of power consumption. As described above, if the defrosting end temperature is varied based on whether or not at least one selection condition selected from among the first condition, the second condition, the third condition, and the fourth condition is satisfied, Since the defrosting operation can be appropriately performed according to the amount of frost formed on the cooler 28, power consumption can be reduced.

Further, when performing the defrosting operation, the control unit 20 sets the defrosting end temperature as the first defrosting temperature based on whether at least all of the first condition, the second condition, the third condition, and the fourth condition are satisfied. Select whether to use the end temperature or the second defrost end temperature. When all of the first, second, third, and fourth conditions are satisfied, it can be said that the degree of frost formation on the cooler 28 is extremely high. Therefore, only when all of the first, second, third, and fourth conditions are satisfied, the temperature detected by the defrosting temperature sensor 29 is the first defrosting end temperature lower than the second defrosting end temperature. If the defrosting operation is performed by the control unit 20 until The amount can be reduced. In other words, there is a high degree of certainty that the defrosting operation can be avoided by the control unit 20 until the temperature detected by the defrosting temperature sensor 29 reaches the first defrosting end temperature despite the large amount of frost. As a result, the situation that the cooler 28 freezes due to insufficient defrosting and the situation that the cooling performance related to the refrigerating cycle deteriorates is less likely to occur.

Further, the control unit 20 determines which of the first defrosting end temperature and the second defrosting end temperature is used as the defrosting end temperature based on whether at least the first condition is satisfied when performing the defrosting operation. is selected, and the number of times the internal temperature detected by the internal temperature sensor 46 exceeds the door opening/closing detection temperature during a set time during the cooling operation is equal to or less than a reference number of times. In the first condition, the opening/closing frequency of the door 14 during the cooling operation is used as an index. It is estimated that the amount of frost formation is small. Therefore, by varying the defrosting end temperature based on whether the first condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler 28 . Moreover, conventionally, if the door 14 is opened and closed even once during the cooling operation, the defrosting operation is continued until the temperature detected by the defrosting temperature sensor 29 reaches the second defrosting end temperature. By varying the defrosting end temperature based on whether or not the first condition with the open/close frequency of the door 14 as an index is satisfied, power consumption can be reduced more favorably. Further, since the opening/closing of the door 14 is detected using the inside temperature sensor 46 for detecting the inside temperature, compared with the case where a switch is provided on the door 14 to detect the opening/closing, such a switch no longer need to be installed.

Further, the control unit 20 determines which of the first defrosting end temperature and the second defrosting end temperature is used as the defrosting end temperature based on whether at least the third condition is satisfied when performing the defrosting operation. is selected, and the difference between the internal temperature detected by the internal temperature sensor 46 and the internal preset temperature is equal to or less than the reference value at least during the set time immediately before the defrosting operation. The third condition uses the difference between the inside temperature and the inside preset temperature at the set time immediately before the defrosting operation as an index. As a result, whether or not the heat exchange efficiency of the refrigerating cycle is reduced due to frost formation on the cooler 28 at the stage immediately before the defrosting operation is performed determines the difference between the inside temperature and the inside preset temperature. will be accurately reflected in Therefore, by varying the defrosting end temperature based on whether the third condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler 28 .

Further, the control unit 20 determines which of the first defrosting end temperature and the second defrosting end temperature is used as the defrosting end temperature based on whether at least the fourth condition is satisfied when the defrosting operation is performed. is selected, and the fourth condition is that the temperature detected by the defrosting temperature sensor 29 is equal to or higher than the reference defrosting temperature at the set time immediately before the defrosting operation. The fourth condition uses the temperature of the cooler 28 or its vicinity at a set time immediately before the defrosting operation as an index. As a result, whether or not the amount of frost formed on the cooler 28 due to the temperature drop of the cooler 28 at the stage immediately before the defrosting operation is performed is accurately reflected in the temperature of the cooler 28 or its vicinity. will be Therefore, by varying the defrosting end temperature based on whether the fourth condition is satisfied, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler 28 .

<Embodiment 2>
Embodiment 2 will be described with reference to FIG. In this second embodiment, the content of the first condition is changed. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 9 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In the first condition according to the present embodiment, the index is the total number of times that the internal temperature detected by the internal temperature sensor during the cooling operation performed immediately before the defrosting operation becomes equal to or higher than the door open/close detection temperature, that is, the cumulative number of times. and Specifically, as shown in FIG. 9, the control unit determines whether the door is opened or closed based on the internal temperature detected by the internal temperature sensor during the period from when the cooling operation is started to when it is finished. The number of times is counted and accumulated, and the accumulated number of times is compared with a reference number of times (for example, two times). For example, the cumulative number of openings and closings of the door during the first cooling operation (left side of FIG. 9) shown in FIG. 9 is three, which is larger than the reference number of two. In this case, the control unit determines that the first condition is not satisfied, and in the first defrosting operation (on the left side of FIG. 9) following the first cooling operation, the defrosting temperature sensor detects The defrosting heater heats the cooler until the temperature (defrosting temperature) reaches the second defrosting end temperature of 20° C. (normal defrosting operation). On the other hand, the cumulative number of openings and closings of the door during the second cooling operation shown in FIG. 9 (on the right side of FIG. 9) is one, which is smaller than the reference number of two. In this case, the control unit determines that the first condition is satisfied, and in the second defrosting operation (on the right side of FIG. 9) following the second cooling operation, the defrosting temperature sensor detects The cooler is heated by the defrosting heater until the temperature of the defrosting reaches 3° C., which is the first defrosting end temperature (simple defrosting operation). If the cumulative number of openings and closings of the door during the cooling operation is two times, which is the same as the reference number of times, the control unit determines that the first condition is satisfied and performs the simple defrosting operation. Even if control is performed using such a first condition as a selection condition, the same actions and effects as those of the first embodiment can be obtained.

<Embodiment 3>
Embodiment 3 will be described with reference to FIG. In the third embodiment, the content of the fourth condition is changed from the first embodiment described above. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 10 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

The fourth condition according to the present embodiment uses the temperature detected by the defrosting temperature sensor during the cooling operation performed immediately before the defrosting operation as an index. Specifically, as shown in FIG. 10, the control unit repeatedly detects the temperature detected by the defrosting temperature sensor during the period from the start of the cooling operation to the end of the cooling operation, and sets the temperature to the reference temperature. Compare with frost temperature. For example, during the first cooling operation shown in FIG. 10 (the left side of FIG. 10), the temperature detected by the defrosting temperature sensor continues to be lower than the reference defrosting temperature of −28° C. It never gets higher than -28°C. In this case, the control unit determines that the fourth condition is not satisfied, and in the first defrosting operation (on the left side of FIG. 10) following the first cooling operation, the temperature detected by the defrosting temperature sensor is The cooler is heated by the defrosting heater until the temperature of the defrosting reaches 20° C., which is the second defrosting end temperature (normal defrosting operation). It should be noted that even if there is a time during which the temperature detected by the defrosting temperature sensor is higher than the reference defrosting temperature of -28°C during the period from the start of the cooling operation to the end of the cooling operation, even once - If there is time for the temperature to become lower than 28°C, the control unit determines that the fourth condition is not satisfied, and performs normal defrosting operation. On the other hand, in the second cooling operation shown in FIG. 10 (the right side of FIG. 10), the temperature detected by the defrosting temperature sensor continues to be higher than the reference defrosting temperature of -28 ° C. It never drops below 28°C. In this case, the control unit determines that the fourth condition is satisfied, and in the second defrosting operation (on the right side of FIG. 10) following the second cooling operation, the temperature detected by the defrosting temperature sensor is The cooler is heated by the defrosting heater until the temperature of the defrosting reaches 3° C., which is the first defrosting end temperature (simple defrosting operation). Even if control is performed using such a fourth condition as a selection condition, the same actions and effects as those of the first embodiment can be obtained.

<Embodiment 4>
Embodiment 4 will be described with reference to FIG. In this fourth embodiment, a second condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 11 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the second condition is satisfied in addition to the selection conditions described in the first embodiment. The second condition uses, as an index, the accumulated time during which the internal temperature detected by the internal temperature sensor during the cooling operation performed immediately before the defrosting operation becomes equal to or lower than the internal preset temperature. Specifically, as shown in FIG. 11, the controller controls the internal temperature detected by the internal temperature sensor to become equal to or lower than the internal temperature set during the period from the start of the cooling operation to the end of the cooling operation. Time is integrated, and the integrated time is compared with a standard integrated time (for example, two hours). If the accumulated time during which the internal temperature is equal to or lower than the internal temperature set temperature is equal to or longer than the standard accumulated time, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated time for the internal temperature to be equal to or lower than the internal temperature set temperature is shorter than the reference accumulated time, the cooling performance of the refrigeration cycle is not properly exhibited, and frost formation on the cooler causes the refrigeration cycle to malfunction. It is presumed that the heat exchange efficiency of the cooler has decreased and the amount of frost on the cooler is large.

For example, the cumulative time during which the internal temperature is equal to or lower than the internal set temperature during the first cooling operation (left side of FIG. 11) shown in FIG. is shorter than In this case, the control unit determines that the second condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 11), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the cumulative time during which the internal temperature during the second cooling operation (on the right side of FIG. 11) shown in FIG. is longer than In this case, the control unit determines that the second condition is satisfied, and if the selection condition described in the first embodiment is also satisfied, the second cooling operation following the second cooling operation (Fig. 11 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the second condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. Further, in the two cooling operations shown in FIG. 11, there is a timing at which the compressor and condenser fans are temporarily stopped. When the internal temperature detected by the internal temperature sensor is detected to be lower than the internal preset temperature, the controller temporarily stops the compressor and condenser fans, and then the internal temperature sensor This is because, when it is detected that the temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, the control unit performs control so that the operation of the compressor and the condenser fan is restarted. If the defrosting end temperature is made different based on whether or not such a second condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, in addition to the selection condition, the control unit uses the integrated time during which the internal temperature detected by the internal temperature sensor during the cooling operation is equal to or lower than the internal preset temperature as a reference. If the second condition of the accumulated time or more is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and if the selection condition and the second condition are not satisfied performs the defrosting operation until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the second condition, the cumulative time when the internal temperature is equal to or lower than the internal temperature is used as an index. It can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the cooler, and it is estimated that the amount of frost formation on the cooler is small. Therefore, by varying the defrosting end temperature based on whether or not the second condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 5>
Embodiment 5 will be described with reference to FIG. Embodiment 5 shows a case where a third condition is added to the selection conditions of Embodiment 1 described above. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 12 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the third condition is satisfied in addition to the selection conditions described in the first embodiment. In the third condition, the index is the number of times the compressors constituting the refrigerating cycle are stopped during the set time immediately before the defrosting operation. Specifically, as shown in FIG. 12, the control unit controls the time period for two hours immediately before the defrosting operation is started (from the time four hours have passed since the cooling operation is started until the defrosting operation is started). 2 hours) is set as the set time, and the number of times the compressor is stopped is counted during the set time, and the number is compared with the reference number of times (for example, once). is determined to be satisfied. The controller can count the number of times the compressor is stopped based on the input voltage to the compressor. When the internal temperature detected by the internal temperature sensor is detected to be equal to or lower than the internal temperature set temperature, the control unit temporarily stops the compressor and condenser fans, and then detects the temperature by the internal temperature sensor. When it is detected that the temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, the operation of the compressor and condenser fans is restarted. Here, if the number of times the compressor is stopped during the cooling operation is equal to or greater than the reference number of times, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled, and the frosting of the cooler Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the number of times the compressor is stopped during the cooling operation is less than the reference number of times, the cooling performance of the refrigeration cycle is not properly exhibited, and heat exchange in the refrigeration cycle is caused by frost formation on the cooler. It is presumed that the efficiency has decreased and the amount of frost on the cooler is large.

For example, in the set time for the first cooling operation (on the left side of FIG. 12) shown in FIG. less than In this case, the control unit determines that the third condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 12), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, in the set time for the second cooling operation (on the right side of FIG. 12) shown in FIG. 12, the number of times the compressor is stopped is one, which is the same as the reference number of times. In this case, the control unit determines that the third condition is satisfied, and if the selection condition described in the first embodiment is also satisfied, the second cooling operation following the second cooling operation (Fig. 12 right side) defrosting operation, the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the third condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not such a third condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the compressor that constitutes the refrigeration cycle together with the cooler is provided, and the controller uses the number of times the compressor is stopped during the cooling operation as a reference in addition to the selection condition. When the third condition that is the number of times or more is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and if the selection condition and the third condition are not satisfied , the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the third condition, the number of times the compressor that constitutes the refrigeration cycle is stopped is used as an index. It can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the cooler, and it is estimated that the amount of frost formation on the cooler is small. be. Therefore, by varying the defrosting end temperature based on whether or not the third condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 6>
Embodiment 6 will be described with reference to FIG. Embodiment 6 shows a modification of Embodiment 1 described above by adding a fourth condition to the selection conditions. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 13 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the fourth condition is satisfied in addition to the selection conditions described in the first embodiment. The fourth condition uses, as an index, the accumulated stop time during which the operation of the compressors constituting the refrigeration cycle is stopped during the cooling operation performed immediately before the defrosting operation. Specifically, as shown in FIG. 13, the control unit integrates the time during which the operation of the compressor is stopped from the start of the cooling operation to the end of the cooling operation. It is determined that the fourth condition is satisfied if the stop time is equal to or longer than the reference stop time (for example, 1.5 hours). The control unit acquires the time during which the operation of the compressor is stopped by, for example, measuring the input voltage to the compressor and the time during which the voltage is input. When the internal temperature detected by the internal temperature sensor is detected to be equal to or lower than the internal temperature set temperature, the control unit temporarily stops the compressor and condenser fans, and then detects the temperature by the internal temperature sensor. When it is detected that the temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, the operation of the compressor and condenser fans is restarted. Here, if the accumulated stop time of the compressor during the cooling operation is equal to or longer than the reference stop time, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated stop time of the compressor during cooling operation is shorter than the reference stop time, the cooling performance of the refrigeration cycle is not properly exhibited, and heat exchange in the refrigeration cycle is delayed due to frost formation on the cooler. It is presumed that the efficiency has decreased and the amount of frost on the cooler is large.

For example, the cumulative stop time of the compressor during the first cooling operation shown in FIG. 13 (on the left side of FIG. 13) is 1 hour, which is shorter than the reference stop time of 1.5 hours. In this case, the control unit determines that the fourth condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 13), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the cumulative stop time of the compressor during the cooling operation for the second time (on the right side of FIG. 13) shown in FIG. 13 is 2 hours, which is longer than the reference stop time of 1.5 hours. In this case, the control unit determines that the fourth condition is satisfied, and if the selection condition described in the first embodiment is also satisfied, the second cooling operation following the second cooling operation (Fig. 13 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the fourth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not such a fourth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the compressor that constitutes the refrigeration cycle together with the cooler is provided, and in addition to the selection conditions, the control unit determines whether the cumulative stop time of the compressor during the cooling operation is the reference stop. When the fourth condition of time or more is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and if the selection condition and the fourth condition are not satisfied , the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the fourth condition, the accumulated stop time of the compressor is used as an index, and if the accumulated stop time of the compressor during cooling operation is equal to or longer than the reference stop time, the cooling performance of the refrigeration cycle is is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the cooler, so the amount of frost formation on the cooler is small. It is estimated to be. Therefore, if the defrosting end temperature is changed based on whether or not the fourth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 7>
Embodiment 7 will be described with reference to FIG. Embodiment 7 shows a case where a fifth condition is added to the selection conditions from Embodiment 1 described above. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 14 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the fifth condition is satisfied in addition to the selection conditions described in the first embodiment. In the fifth condition, the average number of revolutions per unit time of the compressors constituting the refrigeration cycle during the cooling operation performed immediately before the defrosting operation is used as an index. Specifically, as shown in FIG. 14, the control unit calculates the average number of rotations per unit time of the compressor from the time the cooling operation is started to the time it is finished, and calculates the average number of rotations as If the number of revolutions is equal to or less than the standard number of revolutions (for example, 20 times/second), it is determined that the fifth condition is satisfied. In addition, FIG. 14 shows the driving frequency (unit: "Hz") and the average rotational speed (unit: "times/second") of the compressor. The control unit increases or decreases the number of revolutions per unit time of the compressor based on the internal temperature detected by the internal temperature sensor. The number of revolutions is controlled to be higher than when the temperature is lower than the inner set temperature. Here, if the average number of rotations per unit time of the compressor during the cooling operation is equal to or less than the reference number of times, the cooling performance of the refrigeration cycle is properly exhibited, the inside of the refrigerator is properly cooled, and the cooler is installed. It can be said that the heat exchange efficiency of the refrigeration cycle has not deteriorated so much due to frost, and it is presumed that the amount of frost formed on the cooler is small. Conversely, if the average number of revolutions per unit time of the compressor during cooling operation is higher than the reference number of revolutions per hour, the cooling performance of the refrigerating cycle is not properly exhibited, and frost formation on the cooler causes It is presumed that the heat exchange efficiency of the refrigeration cycle has decreased and the amount of frost on the cooler is large.

For example, the average number of revolutions per unit time of the compressor during the first cooling operation (left side of FIG. 14) shown in FIG. It's becoming In this case, the control unit determines that the fifth condition is not satisfied, and regardless of whether the selection conditions described in the first embodiment are satisfied, the first cooling operation that follows the first cooling operation is performed regardless of whether or not the selection condition is satisfied. In the defrosting operation (left side of FIG. 14), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the average number of revolutions per unit time of the compressor during the second cooling operation shown in FIG. 14 (on the right side of FIG. 14) is 20 times/second, which is the same as the reference number of times. In this case, the control unit determines that the fifth condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 14 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the fifth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not such a fifth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the compressor that constitutes the refrigeration cycle together with the cooler is provided, and the control unit, in addition to the selection condition, sets the average rotation speed of the compressor during the cooling operation to the reference rotation speed. If the fifth condition below the number is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and if the selection condition and the fifth condition are not satisfied , the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the fifth condition, the average rotation speed of the compressor is used as an index. is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to frost formation on the cooler, so the amount of frost formation on the cooler is small. It is estimated to be. Therefore, by varying the defrosting end temperature based on whether or not the fifth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 8>
Embodiment 8 will be described with reference to FIG. This eighth embodiment shows a case where a sixth condition is added to the selection conditions from the above-described first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 15 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the sixth condition is satisfied in addition to the selection conditions described in the first embodiment. The sixth condition uses as an index the average current value of the compressors that constitute the refrigeration cycle during the cooling operation that is performed immediately before the defrosting operation. Specifically, as shown in FIG. 15, the control unit calculates the average current value of the compressor from the start of the cooling operation to the end of the cooling operation, and sets the average current value to a reference value (for example, 0.5A), and if it is equal to or less than the reference value, it is determined that the sixth condition is satisfied. Note that FIG. 15 shows the average current value of the compressor. The control unit increases or decreases the current value of the compressor based on the internal temperature detected by the internal temperature sensor. The current value is controlled to be larger than when the current is low. When the compressor is driven at a constant voltage, if the current value of the compressor fluctuates as described above, the power value of the compressor will also fluctuate accordingly. Here, if the average current value of the compressor during the cooling operation is equal to or less than the reference value, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the average current value of the compressor during cooling operation is greater than the reference value, the cooling performance of the refrigeration cycle is not properly demonstrated, and the heat exchange efficiency of the refrigeration cycle is reduced due to frost formation on the cooler. It is presumed that the amount of frost on the cooler is large due to the decrease in

For example, the average current value of the compressor during the first cooling operation (on the left side of FIG. 15) shown in FIG. 15 is 1A, which is higher than the reference value of 0.5A. In this case, the control unit determines that the sixth condition is not satisfied, and regardless of whether the selection conditions described in the first embodiment are satisfied, the first cooling operation that follows the first cooling operation is performed regardless of whether or not the selection condition is satisfied. In the defrosting operation (left side of FIG. 15), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the average current value of the compressor during the second cooling operation shown in FIG. 15 (on the right side of FIG. 15) is 0.5A, which is the same as the reference value. In this case, the control unit determines that the sixth condition is satisfied, and if the selection condition described in the first embodiment is also satisfied, the second cooling operation following the second cooling operation (Fig. 15 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the sixth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is varied based on whether or not such a sixth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can. Although FIG. 15 illustrates the case where the average current value of the compressor is used as an index, it is also possible to use the power value of the compressor, which is a numerical value that fluctuates in conjunction with the current value, as an index.

As described above, according to the present embodiment, the compressor that constitutes the refrigeration cycle together with the cooler is provided, and the control unit, in addition to the selection condition, sets the average current value or power value of the compressor during the cooling operation. is equal to or lower than the reference value, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and the selection condition and the sixth condition are not satisfied. defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the sixth condition, the average current value or power value of the compressor is used as an index, and if the average current value or power value of the compressor is below the reference value during cooling operation, It can be said that the cooling performance of the refrigerating cycle is adequately demonstrated and the inside of the refrigerator is properly cooled, and the heat exchange efficiency of the refrigerating cycle has not decreased significantly due to frost formation on the cooler. It is estimated that the frost amount is small. Therefore, by varying the defrosting end temperature based on whether or not the sixth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 9>
Embodiment 9 will be described with reference to FIG. In the ninth embodiment, a seventh condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 16 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the seventh condition is satisfied in addition to the selection conditions described in the first embodiment. The seventh condition uses, as an index, the accumulated stop time during which the operation of the internal fan is stopped during the cooling operation performed immediately before the defrosting operation. Specifically, as shown in FIG. 16, the control unit integrates the time during which the operation of the internal fan is stopped from the time the cooling operation is started until the time the cooling operation is finished, and the integrated stop time It is determined that the seventh condition is satisfied if the time is longer than the reference stop time (for example, 1.5 hours) compared with the reference stop time. The control unit acquires the time during which the operation of the internal fan is stopped by, for example, measuring the input voltage to the internal fan and the time during which the voltage is input. The controller temporarily stops the compressor, the condenser fan, and the internal fan when it is detected that the internal temperature detected by the internal temperature sensor is equal to or lower than the internal preset temperature. When it is detected that the internal temperature detected by the sensor is equal to or higher than the internal temperature setting, the compressor, the condenser fan, and the internal fan are controlled to resume operation. Here, if the accumulated stop time of the internal fan during cooling operation is longer than the reference stop time, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the container is appropriately cooled, and frost formation on the cooler is prevented. As a result, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated stop time of the internal fan during cooling operation is shorter than the reference stop time, the cooling performance of the refrigeration cycle is not properly exhibited, and the heat generated in the refrigeration cycle is caused by frost formation on the cooler. It is presumed that the exchange efficiency is declining and the amount of frost on the cooler is large.

For example, the cumulative stop time of the internal fan during the first cooling operation shown in FIG. 16 (on the left side of FIG. 16) is 1 hour, which is shorter than the reference stop time of 1.5 hours. In this case, the control unit determines that the seventh condition is not satisfied, and regardless of whether or not the selection conditions described in the first embodiment are satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 16), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches the second defrosting end temperature of 20 ° C. The defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the accumulated stop time of the internal fan during the second cooling operation shown in FIG. 16 (on the right side of FIG. 16) is 2 hours, which is longer than the reference stop time of 1.5 hours. In this case, the control unit determines that the seventh condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 16 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the seventh condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is varied based on whether or not such a seventh condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, an internal fan is provided in the storage main body to circulate the air inside the storage. When the seventh condition that the cumulative stop time of the fan is longer than the reference stop time is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and the selection conditions and the If the condition 7 is not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the seventh condition, the accumulated stop time of the internal fan is used as an index, and if the accumulated stop time of the internal fan during cooling operation is equal to or longer than the reference stop time, the refrigeration cycle is The cooling performance of is properly demonstrated and the inside of the refrigerator is properly cooled. The amount is estimated to be small. Therefore, by varying the defrosting end temperature based on whether or not the seventh condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 10>
Embodiment 10 will be described with reference to FIG. In the tenth embodiment, an eighth condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. 17 are the same as the notations in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the eighth condition is satisfied in addition to the selection conditions described in the first embodiment. The eighth condition uses as an index the accumulated low-speed operation time of the low-speed operation in which the internal fan is operated at low speed during the cooling operation performed immediately before the defrosting operation. Specifically, as shown in FIG. 17, the control unit integrates the time during which the internal fan operates at low speed from the start of the cooling operation to the end of the cooling operation, and calculates the integrated low speed operation time. is compared with a reference operating time (for example, 1.5 hours), and if it is equal to or longer than the reference operating time, it is determined that the eighth condition is satisfied. The controller operates the internal fan at high speed while the compressor is operating during the cooling operation, operates the internal fan at low speed while the compressor is stopped during the cooling operation, and operates the internal fan at low speed during the defrosting operation. Stop the operation of the inner fan. In FIG. 17, the high-speed operating state of the internal fan is indicated as "ON (high speed)," the low-speed operating state of the internal fan is indicated as "ON (low speed)," and the stopped state is indicated as "OFF." It is written. Further, when the internal temperature detected by the internal temperature sensor is detected to be equal to or lower than the internal preset temperature, the control unit temporarily stops the compressor and condenser fans. When it is detected that the detected temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, control is performed so that the operation of the compressor and the condenser fan is restarted. Here, if the accumulated low-speed operation time of the internal fan during the cooling operation is equal to or longer than the reference operating time, the cooling performance of the refrigeration cycle is properly exhibited, the inside of the refrigerator is properly cooled, and the cooler is frosted. It can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much due to this, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated low-speed operation time of the internal fan during cooling operation is shorter than the reference operation time, the cooling performance of the refrigeration cycle is not properly exhibited, and frost formation on the cooler causes the refrigeration cycle to malfunction. It is presumed that the heat exchange efficiency has decreased and the amount of frost on the cooler is large.

For example, the integrated low-speed operation time of the internal fan during the first cooling operation shown in FIG. 17 (on the left side of FIG. 17) is 1 hour, which is shorter than the reference operation time of 1.5 hours. . In this case, the control unit determines that the eighth condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 17), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches the second defrosting end temperature of 20 ° C. The defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the accumulated low-speed operation time of the internal fan during the second cooling operation shown in FIG. 17 (the right side of FIG. 17) is 2 hours, which is longer than the standard operation time of 1.5 hours. . In this case, the control unit determines that the eighth condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 17 right side) defrosting operation, the temperature detected by the defrosting temperature sensor, until the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, heating the cooler by the defrosting heater (simple defrosting operation ). Note that even when the eighth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is made different based on whether or not the eighth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the compressor that constitutes the refrigeration cycle together with the cooler, and the internal fan that is arranged in the storage body and circulates the air in the storage are provided, and the control unit operates the internal fan at high speed while the compressor is in operation, operates the internal fan at low speed while the compressor is stopped, and stops the operation of the internal fan during defrosting operation. In addition to the conditions, if the eighth condition is satisfied that the cumulative low-speed operation time of the internal fan during the cooling operation is equal to or longer than the reference operation time, the temperature detected by the defrosting temperature sensor is the first defrosting end temperature. If the selection condition and the eighth condition are not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the eighth condition, the integrated low-speed operating time of the internal fan whose operating speed is controlled in synchronization with the operating state of the compressor is used as an index, and the integrated low-speed operating time of the internal fan during the cooling operation is the reference operating time. If it is above, it means that the cooling performance of the refrigeration cycle is properly demonstrated and the inside of the refrigerator is properly cooled even if the compressor and the inside fan are in low operation. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Therefore, by varying the defrosting end temperature based on whether or not the eighth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 11>
Embodiment 11 will be described with reference to FIG. In the eleventh embodiment, a ninth condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation of 18 in the figure is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the ninth condition is satisfied in addition to the selection conditions described in the first embodiment. The ninth condition uses the average current value of the internal fan during the cooling operation performed immediately before the defrosting operation as an index. Specifically, as shown in FIG. 18, the control unit calculates the average current value of the internal fan during the period from the start of the cooling operation to the end of the cooling operation, and sets the average current value to the reference value ( For example, when compared with 0.05 A), it is determined that the ninth condition is satisfied if the reference value is not exceeded. Note that FIG. 18 shows the average current value of the internal fan. The control unit increases or decreases the current value of the internal fan based on the internal temperature detected by the internal temperature sensor. The current value is controlled to increase compared to the case where the current value is lower than . When the internal fan is driven at a constant voltage, if the current value of the internal fan fluctuates as described above, the electric power value of the internal fan will also fluctuate accordingly. Here, if the average current value of the internal fan during the cooling operation is equal to or less than the reference value, the cooling performance of the refrigerating cycle is properly demonstrated and the inside of the refrigerator is properly cooled. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the average current value of the internal fan during cooling operation is greater than the reference value, the cooling performance of the refrigerating cycle is not properly exhibited, and heat exchange in the refrigerating cycle is reduced due to frost formation on the cooler. It is presumed that the efficiency has decreased and the amount of frost on the cooler is large.

For example, the average current value of the internal fan during the first cooling operation shown in FIG. 18 (on the left side of FIG. 18) is 0.1A, which is higher than the reference value of 0.05A. In this case, the control unit determines that the ninth condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 18), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the average current value of the inside fan during the second cooling operation shown in FIG. In this case, the control unit determines that the ninth condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 18 right side) defrosting operation, the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the ninth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not such a ninth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can. Although FIG. 18 illustrates the case where the average current value of the internal fan is used as an index, it is also possible to use the power value of the internal fan, which is a numerical value that fluctuates in conjunction with the current value, as an index.

As described above, according to the present embodiment, an internal fan is provided in the storage main body to circulate the air inside the storage. If the ninth condition that the average current value or power value of the fan is equal to or lower than the reference value is satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature, and the selection condition And when the ninth condition is not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the ninth condition, the average current value or power value of the internal fan is used as an index, and if the average current value or power value of the internal fan during cooling operation is equal to or less than the reference value, the internal fan is operating at a low level. Even if there is, the cooling performance of the refrigerating cycle is properly demonstrated and the inside of the refrigerator is properly cooled. It is estimated that the amount of frost on the cooler is small. Therefore, by varying the defrosting end temperature based on whether or not the ninth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 12>
Embodiment 12 will be described with reference to FIG. In the twelfth embodiment, a tenth condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Also, the notation in FIG. 19 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the tenth condition is satisfied in addition to the selection conditions described in the first embodiment. The tenth condition uses, as an index, the accumulated stop time during which the operation of the condenser fan is stopped during the cooling operation performed immediately before the defrosting operation. Specifically, as shown in FIG. 19, the control unit integrates the time during which the operation of the condenser fan is stopped from the start of the cooling operation to the end of the cooling operation. It is determined that the tenth condition is satisfied if the time is longer than the reference stop time (for example, 1.5 hours) compared with the reference stop time. The control unit acquires the time during which the operation of the condenser fan is stopped by, for example, measuring the input voltage to the condenser fan and the time during which the voltage is input. When the internal temperature detected by the internal temperature sensor is detected to be equal to or lower than the internal temperature set temperature, the control unit temporarily stops the compressor and condenser fans, and then detects the temperature by the internal temperature sensor. When it is detected that the temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, the operation of the compressor and condenser fans is restarted. Here, if the accumulated stop time of the condenser fan during the cooling operation is longer than the reference stop time, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled, and frost formation on the cooler is prevented. As a result, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated stop time of the condenser fan during cooling operation is shorter than the reference stop time, the cooling performance of the refrigeration cycle is not properly exhibited, and the heat generated in the refrigeration cycle is caused by frost formation on the cooler. It is presumed that the exchange efficiency is declining and the amount of frost on the cooler is large.

For example, the accumulated stop time of the condenser fan during the first cooling operation shown in FIG. 19 (on the left side of FIG. 19) is 1 hour, which is shorter than the reference stop time of 1.5 hours. In this case, the control unit determines that the tenth condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 19), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches the second defrosting end temperature of 20 ° C. The defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the accumulated stop time of the condenser fan during the cooling operation for the second time (on the right side of FIG. 19) shown in FIG. 19 is 2 hours, which is longer than the reference stop time of 1.5 hours. In this case, the control unit determines that the tenth condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 19), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the tenth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not such a tenth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the condenser that constitutes the refrigeration cycle together with the cooler and the condenser fan that blows air to the condenser are provided. When the tenth condition is satisfied that the accumulated stop time of the condenser fan is equal to or longer than the reference stop time during operation, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature. If the selection condition and the tenth condition are not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the tenth condition, the accumulated stop time of the condenser fan that blows air to the condenser is used as an index, and if the accumulated stop time of the condenser fan during cooling operation is equal to or longer than the reference stop time, the condenser fan is operating at a low level. Even if there is, the cooling performance of the refrigerating cycle is properly demonstrated and the inside of the refrigerator is properly cooled. It is estimated that the amount of frost on the cooler is small. Therefore, if the defrosting end temperature is changed based on whether or not the tenth condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 13>
Embodiment 13 will be described with reference to FIG. In the thirteenth embodiment, the eleventh condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Moreover, the notation in FIG. 20 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the eleventh condition is satisfied in addition to the selection conditions described in the first embodiment. The eleventh condition uses the average current value of the condenser fan during the cooling operation performed immediately before the defrosting operation as an index. Specifically, as shown in FIG. 20, the control unit calculates the average current value of the condenser fan during the period from the start of the cooling operation to the end of the cooling operation, and sets the average current value to the reference value ( For example, when compared with 0.05 A), it is determined that the eleventh condition is satisfied if the reference value is not exceeded. Note that FIG. 20 shows the average current value of the condenser fan. The controller increases or decreases the current value of the condenser fan based on the internal temperature detected by the internal temperature sensor. The current value is controlled to increase compared to the case where the current value is lower than . When the condenser fan is driven at a constant voltage, if the electric current value of the condenser fan fluctuates as described above, the electric power value of the condenser fan will also fluctuate accordingly. Here, if the average current value of the condenser fan during the cooling operation is equal to or less than the reference value, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled. Therefore, it can be said that the heat exchange efficiency of the refrigeration cycle has not decreased so much, and it is estimated that the amount of frost formation on the cooler is small. Conversely, if the average current value of the condenser fan during cooling operation is greater than the reference value, the cooling performance of the refrigerating cycle is not properly exhibited, and heat exchange in the refrigerating cycle is It is presumed that the efficiency has decreased and the amount of frost on the cooler is large.

For example, the average current value of the condenser fan during the first cooling operation (on the left side of FIG. 20) shown in FIG. 20 is 0.1A, which is higher than the reference value of 0.05A. In this case, the control unit determines that the eleventh condition is not satisfied, and regardless of whether the selection conditions described in the first embodiment are satisfied, the first cooling operation following the first cooling operation is performed. In the defrosting operation (left side of FIG. 20), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the average current value of the condenser fan during the second cooling operation shown in FIG. 20 (on the right side of FIG. 20) is 0.05A, which is the same as the reference value. In this case, the control unit determines that the eleventh condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 20 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the eleventh condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. If the defrosting end temperature is changed based on whether or not the eleventh condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can. Although FIG. 20 illustrates the case where the average current value of the condenser fan is used as an index, it is also possible to use the electric power value of the condenser fan, which is a numerical value that fluctuates in conjunction with the current value, as an index.

As described above, according to the present embodiment, the condenser that constitutes the refrigeration cycle together with the cooler, and the condenser fan that blows air to the condenser are provided. When the average current value or power value of the condenser fan during operation satisfies the eleventh condition that the average current value or power value is equal to or less than the reference value, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature. If the selection condition and the eleventh condition are not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. The eleventh condition uses the average current value or power value of the condenser fan as an index. Even if there is, the cooling performance of the refrigerating cycle is properly demonstrated and the inside of the refrigerator is properly cooled, and it can be said that the heat exchange efficiency of the refrigerating cycle has not decreased so much due to frost formation on the cooler. It is estimated that the amount of frost on the cooler is small. Therefore, if the defrosting end temperature is changed based on whether or not the eleventh condition is satisfied in addition to the selection condition, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Embodiment 14>
Embodiment 14 will be described with reference to FIG. In the fourteenth embodiment, a twelfth condition is added to the selection conditions of the first embodiment. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Moreover, the notation in FIG. 21 is the same as the notation in FIGS. 4 to 8 described in the first embodiment.

In this embodiment, the control unit performs the defrosting operation so as to change the defrosting end temperature based on whether or not the twelfth condition is satisfied in addition to the selection conditions described in the first embodiment. The twelfth condition uses, as an index, the accumulated time during which the temperature detected by the clogging temperature sensor during the cooling operation performed immediately before the defrosting operation becomes lower than the reference temperature. Specifically, as shown in FIG. 21, the control unit sets the temperature detected by the clogging temperature sensor during the operation of the compressor to the reference temperature ( 30° C.) is accumulated, and if the accumulated time is equal to or longer than the reference accumulated time (for example, 1.5 hours), it is determined that the twelfth condition is satisfied. In addition, in FIG. 21, the temperature detected by the clogging temperature sensor is indicated together with the reference temperature (broken line in the figure). This reference temperature is an assumed value of the ambient temperature (outside air temperature) of the freezer. The temperature detected by the clogging temperature sensor while the compressor and condenser fans are in operation is, for example, about 35° C., which is higher than the above reference temperature. The temperature detected by the clogging temperature sensor in the stopped state tends to be about the same as or lower than the above reference temperature. Therefore, if the accumulated time during which the temperature detected by the clogging temperature sensor is higher than the reference temperature is long, the refrigeration cycle is operating at a high level, and the temperature detected by the clogging temperature sensor is lower than the reference temperature. If the cumulative time is long, it can be said that the refrigeration cycle is operating at a low rate. Therefore, if the accumulated time for the temperature detected by the clogging temperature sensor to be equal to or lower than the reference temperature is equal to or longer than the reference accumulated time, the cooling performance of the refrigeration cycle is properly exhibited and the inside of the refrigerator is properly cooled. It can be said that the heat exchange efficiency of the refrigeration cycle did not decrease so much due to the frost formation on the cooler, so it is estimated that the amount of frost formation on the cooler is small. Conversely, if the accumulated time for the temperature detected by the clogging temperature sensor to be equal to or lower than the reference temperature is shorter than the reference accumulated time, the cooling performance of the refrigeration cycle is not properly exhibited, and the cooling performance is caused by frost formation on the cooler. As a result, the heat exchange efficiency of the refrigeration cycle is declining, and it is presumed that the amount of frost on the cooler is large.

For example, the cumulative time during which the temperature detected by the clogging temperature sensor during the first cooling operation shown in FIG. 21 (on the left side of FIG. 21) is equal to or lower than the reference temperature is one hour, which is the standard cumulative time. Less than 1.5 hours. In this case, the control unit determines that the twelfth condition is not satisfied, and regardless of whether or not the selection condition described in the first embodiment is satisfied, the first cooling operation that follows the first cooling operation is performed. In the defrosting operation (left side of FIG. 21), the temperature detected by the defrosting temperature sensor (defrosting temperature) reaches 20° C., which is the second defrosting end temperature, until the defrosting heater heats the cooler. (normal defrosting operation). On the other hand, the accumulated time during which the temperature detected by the clogging temperature sensor during the cooling operation for the second time (on the right side of FIG. 21) is equal to or lower than the reference temperature shown in FIG. 21 is two hours, which is the reference accumulated time. longer than 1.5 hours. In this case, the control unit determines that the twelfth condition is satisfied, and if the selection conditions described in the first embodiment are also satisfied, the second cooling operation following the second cooling operation (Fig. 21 right side), the temperature detected by the defrosting temperature sensor reaches 3 ° C., which is the first defrosting end temperature, until the defrosting heater heats the cooler (simple defrosting operation ). Note that even when the twelfth condition is satisfied, if the selection condition described in the first embodiment is not satisfied, the control unit performs the normal defrosting operation. Further, in the two cooling operations shown in FIG. 21, there is a timing at which the compressor and condenser fans are temporarily stopped. When the internal temperature detected by the internal temperature sensor is detected to be lower than the internal preset temperature, the controller temporarily stops the compressor and condenser fans, and then the internal temperature sensor This is because, when it is detected that the temperature inside the refrigerator is equal to or higher than the preset temperature inside the refrigerator, the control unit performs control so that the operation of the compressor and the condenser fan is restarted. By making the defrosting end temperature different based on whether or not such a twelfth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. can.

As described above, according to the present embodiment, the compressor that forms the refrigeration cycle together with the cooler, the condenser that forms the refrigeration cycle together with the cooler and the compressor, the condenser fan that blows air to the condenser, and the condensation and a clogging temperature sensor (condenser temperature sensor) that detects the temperature in the vicinity of the condenser or the condenser. is lower than the reference temperature satisfies the twelfth condition that the accumulated time is equal to or greater than the reference accumulated time, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the first defrosting end temperature. If the selection condition and the twelfth condition are not satisfied, the defrosting operation is performed until the temperature detected by the defrosting temperature sensor reaches the second defrosting end temperature. In the twelfth condition, the accumulated time during which the temperature detected by the clogging temperature sensor during cooling operation becomes lower than the reference temperature is used as an index, and if the above accumulated time during cooling operation is equal to or greater than the reference accumulated time, The cooling performance of the refrigeration cycle is adequately demonstrated even when the compressor is operating at low speed, and the inside of the refrigerator is properly cooled. Therefore, it is presumed that the amount of frost on the cooler is small. Therefore, by varying the defrosting end temperature based on whether or not the twelfth condition is satisfied in addition to the selection conditions, it is possible to perform an appropriate defrosting operation according to the amount of frost formed on the cooler. .

<Other embodiments>
The technology disclosed in the present specification is not limited to the embodiments described by the above description and drawings, and includes the following embodiments, for example.

(1) It is also possible to add an outside temperature sensor (ambient temperature thermistor) for detecting the outside temperature (ambient temperature) of the freezer 10 . In that case, the controller 20 detects the defrosting temperature sensor 29 when the outside temperature detected by the outside temperature sensor satisfies the thirteenth condition that the outside temperature detected by the outside temperature sensor is equal to or higher than the reference temperature (for example, 25° C.) in addition to the selection conditions. Defrost operation is performed until the temperature at which the defrost is applied becomes the first defrost end temperature, and if the selection condition and the thirteenth condition are not satisfied, the temperature detected by the defrost temperature sensor 29 becomes the second defrost end temperature. Perform defrosting operation until

(2) It is also possible to change the content of the second condition to "the internal temperature detected by the internal temperature sensor 46 is equal to or higher than the reference set temperature at the set time immediately before the defrosting operation".

(3) The third condition is defined as ``the difference between the internal temperature detected by the internal temperature sensor 46 and the internal set temperature is equal to or less than the reference value during the period from the start of the cooling operation to the end of the cooling operation''. It is also possible to change to the contents of

(4) The content of the first condition is that "the number of times that the internal temperature detected by the internal temperature sensor 46 exceeds the door opening/closing detection temperature during the set time immediately before the defrosting operation is equal to or less than the reference number of times". It can also be changed.

(5) The first condition is defined as "opening/closing per unit time by dividing the total number of times that the internal temperature detected by the internal temperature sensor 44 during the cooling operation exceeds the door open/close detection temperature by the cooling operation time. It is also possible to change the content to "calculate the number of times, and the number of opening/closing times per unit time is equal to or less than the reference number of times".

(6) The specific numerical value of the reference number of times according to the first condition described in the first embodiment can be changed to two or more times.

(7) The specific numerical value of the set time related to the first condition described in Embodiment 1 can be shorter or longer than 15 minutes.

(8) The specific numerical value of the reference number of times according to the first condition described in the second embodiment can be changed to 1 or 3 or more.

(9) The specific numerical value of the reference setting temperature related to the second condition can be changed to a temperature other than -22°C.

(10) The specific numerical value of the reference value related to the third condition can be changed to an absolute temperature other than 1K.

(11) The specific numerical value of the set time related to the third condition can be shorter or longer than two hours.

(12) The specific numerical value of the reference defrost temperature related to the fourth condition can be changed to a temperature other than -28°C.

(13) The specific numerical value of the set time related to the fourth condition described in Embodiment 1 can be shorter or longer than 15 minutes.

(14) A specific numerical value of the reference accumulated time according to the second condition described in the fourth embodiment can be shorter or longer than two hours.

(15) The specific numerical value of the set time according to the third condition described in Embodiment 5 can be shorter or longer than two hours. Also, the reference number of times for the third condition may be two or more.

(16) Change the content of the third condition described in the fifth embodiment to ``the number of times the compressor 22 is stopped between the start and end of the cooling operation is equal to or greater than the reference number of times''. It is also possible to

(17) The specific numerical value of the reference stop time according to the fourth condition described in Embodiment 6 can be shorter or longer than 1.5 hours.

(18) The specific numerical value of the reference number of rotations according to the fifth condition described in Embodiment 7 can be made smaller or larger than 20 times/second.

(19) The specific numerical value of the reference value according to the sixth condition described in the eighth embodiment can be made smaller or larger than 0.5A.

(20) A specific numerical value of the reference stop time according to the seventh condition described in the ninth embodiment can be shorter or longer than 1.5 hours.

(21) The specific numerical value of the reference operating time according to the eighth condition described in the tenth embodiment can be shorter or longer than 1.5 hours.

(22) The specific numerical value of the reference value according to the ninth condition described in the eleventh embodiment can be made smaller or larger than 0.05A.

(23) The specific numerical value of the reference stop time according to the tenth condition described in the twelfth embodiment can be shorter or longer than 1.5 hours.

(24) The specific numerical value of the reference value according to the eleventh condition described in the thirteenth embodiment can be made smaller or larger than 0.05A.

(25) The specific numerical value of the reference cumulative time according to the twelfth condition described in the fourteenth embodiment can be shorter or longer than 1.5 hours.

(26) In addition to the heater defrost method, the control unit 20 performs an off-cycle defrost method of stopping the operation of the cooling device 18 and operating the internal fan 44 to melt the frost adhering to the cooler 28. Also good.

(27) The present technology can also be applied to a cold storage (such as a refrigerator) other than the freezer 10 .

DESCRIPTION OF SYMBOLS 10... Freezer (cooling storage), 12... Storage body, 12A... Opening, 14... Door, 20... Control part, 22... Compressor, 24... Condenser fan, 25... Clogging temperature sensor (third sensor), 26 Condenser 27 Defrosting heater (heating unit) 28 Cooler (evaporator) 29 Defrosting temperature sensor (second sensor) 44 Internal fan 46 Internal temperature sensor (first sensor)

Claims (16)

a storage body having an opening;
a door that opens and closes the opening;
a first sensor that detects the internal temperature;
an evaporator that constitutes a refrigeration cycle;
a heating unit that heats the evaporator;
a second sensor that detects the temperature of the evaporator or the vicinity of the evaporator;
The cooling operation is performed by controlling the refrigerating cycle so that the internal temperature detected by the first sensor becomes the internal preset temperature, and the heating unit is controlled to remove the temperature detected by the second sensor. A control unit that performs defrosting operation until the frost end temperature is reached,
The control unit detects opening and closing of the door when the internal temperature detected by the first sensor reaches or exceeds a predetermined door opening/closing detection temperature. A first condition that the number of times that the temperature inside the refrigerator detected by the detection temperature is equal to or higher than the door open/close detection temperature is equal to or less than a reference number of times, and a second condition that the preset temperature inside the refrigerator is equal to or higher than the reference preset temperature during the cooling operation. and a third condition that the difference between the inside temperature detected by the first sensor during the cooling operation and the inside preset temperature is equal to or less than a reference value, and detected by the second sensor during the cooling operation. and a fourth condition that the temperature detected by the second sensor is equal to or higher than the reference defrosting temperature, the temperature detected by the second sensor is the defrosting end temperature. The defrosting operation is performed until the defrosting end temperature reaches 1 defrosting end temperature, and if the selection condition is not satisfied, the temperature detected by the second sensor is the defrosting end temperature higher than the first defrosting end temperature. A cooling storage that performs the defrosting operation until a certain second defrosting end temperature is reached. When performing the defrosting operation, the control unit sets the defrosting end temperature based on whether at least all of the first condition, the second condition, the third condition, and the fourth condition are satisfied. 2. The cold storage according to claim 1, wherein which of said first defrosting end temperature and said second defrosting end temperature is used is selected. When the defrosting operation is performed, the control unit determines which of the first defrosting end temperature and the second defrosting end temperature as the defrosting end temperature based on whether at least the first condition is satisfied. is used, and the number of times the internal temperature detected by the first sensor exceeds the door open/close detection temperature during the set time during the cooling operation is equal to or less than a reference number of times. A cold store according to claim 1 or claim 2 as a condition. When the defrosting operation is performed, the control unit selects any one of the first defrosting end temperature and the second defrosting end temperature as the defrosting end temperature based on whether at least the third condition is satisfied. is used, and the difference between the internal temperature detected by the first sensor and the internal set temperature detected by the first sensor is equal to or less than a reference value at least during the set time immediately before the defrosting operation. The cold storage according to any one of claims 1 to 3, wherein three conditions are set. When the defrosting operation is performed, the control unit determines which of the first defrosting end temperature and the second defrosting end temperature as the defrosting end temperature based on whether at least the fourth condition is satisfied. , and the fourth condition is that the temperature detected by the second sensor at the set time immediately before the defrosting operation is equal to or higher than the reference defrosting temperature. A cold store according to any one of the preceding claims. In addition to the selection condition, the control unit provides a second integrated time in which the internal temperature detected by the first sensor during the cooling operation is equal to or lower than the internal set temperature is equal to or greater than a reference integrated time. When the condition is satisfied, the defrosting operation is performed until the temperature detected by the second sensor reaches the first defrosting end temperature, and when the selection condition and the second condition are not satisfied, the The cooling storage according to any one of claims 1 to 5, wherein the defrosting operation is performed until the temperature detected by the second sensor reaches the second defrosting end temperature. A compressor that configures the refrigeration cycle together with the evaporator,
The control unit, in addition to the selection condition, satisfies a third condition that the number of times the compressor is stopped during the cooling operation is equal to or greater than a reference number of times, the temperature detected by the second sensor increases. The defrosting operation is performed until the first defrosting end temperature is reached, and when the selection condition and the third condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature. 7. The cold storage according to any one of claims 1 to 6, wherein the defrosting operation is performed until the temperature is reduced. A compressor that configures the refrigeration cycle together with the evaporator,
The control unit, in addition to the selection condition, satisfies a fourth condition that the cumulative stop time of the compressor during the cooling operation is equal to or longer than a reference stop time, the temperature detected by the second sensor increases. The defrosting operation is performed until the first defrosting end temperature is reached, and when the selection condition and the fourth condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature. 8. The cold storage according to any one of claims 1 to 7, wherein the defrosting operation is performed until the defrosting is complete. A compressor that configures the refrigeration cycle together with the evaporator,
The control unit, in addition to the selection condition, satisfies a fifth condition that the average rotation speed of the compressor is equal to or lower than a reference rotation speed during the cooling operation, the temperature detected by the second sensor is increased. The defrosting operation is performed until the first defrosting end temperature is reached, and when the selection condition and the fifth condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature. 9. The cold storage according to any one of claims 1 to 8, wherein the defrosting operation is performed until the temperature is reduced. A compressor that configures the refrigeration cycle together with the evaporator,
In addition to the selection conditions, the control unit detects a sixth condition that the average current value or power value of the compressor during the cooling operation is equal to or less than a reference value, detected by the second sensor. The defrosting operation is performed until the temperature reaches the first defrosting end temperature, and if the selection condition and the sixth condition are not satisfied, the temperature detected by the second sensor reaches the second defrosting end temperature. 10. The cold storage according to any one of claims 1 to 9, wherein the defrosting operation is performed until the temperature is reached. An internal fan is arranged in the storage body and circulates the air inside the storage,
In addition to the selection condition, the control unit controls the temperature detected by the second sensor when a seventh condition is satisfied in which the cumulative stop time of the internal fan during the cooling operation is equal to or longer than a reference stop time. is the first defrosting end temperature, and if the selection condition and the seventh condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature The cold storage according to any one of claims 1 to 10, wherein the defrosting operation is performed until the a compressor that configures the refrigeration cycle together with the evaporator;
an internal fan arranged in the storage body to circulate the air in the storage,
The control unit operates the internal fan at high speed while the compressor is operating, operates the internal fan at low speed while the compressor is stopped, and operates the internal fan during the defrosting operation. When the operation of the fan is stopped and, in addition to the selection condition, an eighth condition is satisfied in which the cumulative low-speed operation time of the internal fan during the cooling operation is equal to or longer than the reference operation time, the second sensor The defrosting operation is performed until the detected temperature reaches the first defrosting end temperature, and when the selection condition and the eighth condition are not satisfied, the temperature detected by the second sensor is set to the second temperature. The cooling storage according to any one of claims 1 to 11, wherein the defrosting operation is performed until the defrosting end temperature is reached. An internal fan is arranged in the storage body and circulates the air inside the storage,
In addition to the selection conditions, the control section satisfies a ninth condition that the average current value or power value of the internal fan during the cooling operation is equal to or less than a reference value, detected by the second sensor. The defrosting operation is performed until the temperature detected by the second defrosting end temperature reaches the first defrosting end temperature, and if the selection condition and the ninth condition are not satisfied, the temperature detected by the second sensor is the second defrosting 13. The cold storage according to any one of claims 1 to 12, wherein the defrosting operation is performed until the end temperature is reached. a condenser that forms the refrigeration cycle together with the evaporator;
and a condenser fan that blows air to the condenser,
The control unit, in addition to the selection condition, satisfies a tenth condition that the cumulative stop time of the condenser fan during the cooling operation is equal to or longer than a reference stop time, the temperature detected by the second sensor. is the first defrosting end temperature, and when the selection condition and the tenth condition are not satisfied, the temperature detected by the second sensor is the second defrosting end temperature 14. The cold storage according to any one of claims 1 to 13, wherein the defrosting operation is performed until the a condenser that forms the refrigeration cycle together with the evaporator;
and a condenser fan that blows air to the condenser,
In addition to the selection conditions, the control section satisfies an eleventh condition that the average current value or power value of the condenser fan during the cooling operation is equal to or less than a reference value, detected by the second sensor. The defrosting operation is performed until the temperature detected by the second defrosting end temperature reaches the first defrosting end temperature, and if the selection condition and the eleventh condition are not satisfied, the temperature detected by the second sensor is the second defrosting 15. The cold storage according to any one of claims 1 to 14, wherein the defrosting operation is performed until the end temperature is reached. a compressor that configures the refrigeration cycle together with the evaporator;
a condenser that forms the refrigeration cycle together with the evaporator and the compressor;
a condenser fan for blowing air to the condenser;
and a third sensor that detects the temperature of the condenser or the vicinity of the condenser,
The control unit satisfies a twelfth condition that, in addition to the selection condition, the accumulated time during which the temperature detected by the third sensor is lower than the reference temperature during the cooling operation is equal to or greater than the reference accumulated time. performs the defrosting operation until the temperature detected by the second sensor reaches the first defrosting end temperature, and when the selection condition and the twelfth condition are not satisfied, detected by the second sensor 16. The cold storage according to any one of claims 1 to 15, wherein the defrosting operation is performed until the temperature to be defrosted reaches the second defrosting end temperature.

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