Patent Publication Number: US-2019170433-A1

Title: Control device, program, control method of refrigerator, and refrigerator

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to a control device, a program, a control method of a refrigerator, and a refrigerator. 
     2. Description of the Related Art 
     In an inexpensive refrigerator including one freezer compartment and one refrigerator compartment, an internal temperature of the refrigerator is maintained by a compressor for circulating a cooling medium, an evaporator vaporizing the cooling medium, and an in-refrigerator fan for blowing cool air. 
     Recently, in order to reduce energy consumption in the refrigerator, a rotational speed of the compressor is controlled according to an outside air temperature. However, ratios of the amount of heat leakage from the outside air temperature to the inside of the refrigerator are different in a plurality of storage compartments such as the refrigerator compartment and the freezer compartment, respectively. In addition, the ratio of the amount of heat leakage changes depending on contents or quantity in each storage compartment. Furthermore, the temperature in the storage compartment rises or falls depending on opening and closing situations of each storage compartment. Accordingly, methods of cooling the separate storage compartments are relatively different from each other. 
     In contrast to this, in a refrigerator including a damper or the like, by controlling opening and closing of the damper according to a temperature change of each storage compartment, the amount of circulation of cool air can be controlled for each storage compartment. Meanwhile, in a case where the damper or the like is not used to make the refrigerator inexpensive, it is impossible to individually control an internal temperature of each storage compartment. Accordingly, in a case where temperature control is performed based on the temperature of either one of the storage compartments, there is a problem that overcooling or insufficient cooling of the other storage compartment occurs. 
     A refrigerator in which ON/OFF of a compressor is performed based on a temperature of the refrigerator compartment, and an application voltage of a cooling fan (in-refrigerator fan) changes depending on whether or not an outside air temperature is lower than or equal to a predetermined temperature. 
     However, the compressor is turned on and off based on the temperature of one of the storage compartments, but since a temperature of the other storage compartment is not managed, it is impossible to cope with a case where the temperatures of the two storage compartments change relatively depending on contents or quantity in each storage compartment. Therefore, there is a possibility that overcooling or insufficient cooling of one storage compartment occurs. 
     SUMMARY OF THE INVENTION 
     An example embodiment of the present disclosure provides a control device that controls a compressor and an in-refrigerator fan to circulate cool air in the refrigerator including a first storage compartment and a second storage compartment, includes a controller that controls a rotational speed of the compressor and the in-refrigerator fan based on an outside air temperature of the refrigerator, and a calculator that calculates an average internal temperature of the second storage compartment during one cycle from when the compressor stops an operation until when the compressor stops a next operation, in which the controller controls an operation and stoppage of the compressor based on an internal temperature of the first storage compartment and corrects the rotational speed of the in-refrigerator fan when the compressor operates during a next cycle based on a comparison result between the average temperature and a threshold. 
     In an exemplary embodiment of the present disclosure, a non-transitory computer-readable medium includes a program that causes a computer to function as the control device. 
     In an example embodiment of the present disclosure, a control method is a method of controlling, in a refrigerator including a first storage compartment and a second storage compartment, a compressor and an in-refrigerator fan to circulate cool air in the refrigerator. The method includes a control process of causing a process core to control a rotational speed of the compressor and the in-refrigerator fan based on an outside air temperature of the refrigerator, and a calculation process of causing a process core to calculate an average internal temperature of the second storage compartment during one cycle from when the compressor stops an operation until when the compressor stops a next operation. In the control process, the processor core controls an operation and stoppage of the compressor based on an internal temperature of the first storage compartment and corrects the rotational speed of the in-refrigerator fan when the compressor operates during the next cycle based on a comparison result between the average temperature and a threshold. 
     In an example embodiment of the present disclosure, a refrigerator includes a first storage compartment, a second storage compartment, a first storage compartment temperature sensor, a second storage compartment temperature sensor, an outside air temperature sensor, a compressor, an evaporator, an in-refrigerator fan, and the control device. The first storage compartment temperature sensor measures an internal temperature of the first storage compartment. The second storage compartment temperature sensor measures an internal temperature of the second storage compartment. The outside air temperature sensor measures an outside air temperature of the refrigerator. The compressor circulates a cooling medium. The evaporator generates cool air by vaporizing the cooling medium. The in-refrigerator fan circulates the cool air in the refrigerator. 
     The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the example embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a schematic overall configuration of a refrigerator according to an example embodiment of the present disclosure. 
         FIG. 2  is a diagram illustrating a functional block of a control device of the refrigerator. 
         FIG. 3  is a flowchart illustrating processing in which the control device determines a rotational speed of an in-refrigerator fan. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, example embodiments of the present disclosure will now be described with reference to the drawings. A scope of the present disclosure is not limited to the following example embodiments and can be randomly changed within a scope of a technical idea of the present disclosure. In addition, in the following drawings, in order to make each configuration easy to understand, there is a case where a scale, a number, and the like in each structure are made different from an actual scale. 
       FIG. 1  is a diagram illustrating a schematic overall configuration of a refrigerator according to one embodiment of the present disclosure. A refrigerator  1  includes two refrigerator compartments, which are a freezer compartment  2  that is a first storage compartment and a refrigerator compartment  3  that is a second storage compartment. The freezer compartment  2  and the refrigerator compartment  3  are cooled by a compressor  4  that circulates a cooling medium, an evaporator  5  that generating cool air by vaporizing the cooling medium, and an in-refrigerator fan  6  that circulates the cool air generated by the evaporator  5  in a refrigerator  1 . In  FIG. 1 , the refrigerator  1  has a configuration in which the freezer compartment  2  is located on an upper side of the refrigerator compartment  3  in a vertical direction, but the present disclosure is not limited to this form. For example, the freezer compartment  2  may be located on a lower side of the refrigerator compartment  3  in the vertical direction. 
     The compressor  4  is provided in a machine compartment (not illustrated) behind the refrigerator  1 . A condenser, a capillary tube, and the evaporator  5  are connected to the compressor  4  via a refrigerant pipe (not illustrated) that makes a cooling medium flow therethrough, and the cooling medium circulates. The in-refrigerator fan  6  supplies the cool air generated by the evaporator  5  to the freezer compartment  2  via an ejection hole  11 . The in-refrigerator fan  6  supplies the cool air generated by the evaporator  5  to the refrigerator compartment  3  from the ejection hole  12  via a vent hole not illustrated in  FIG. 1 . The cool air delivered to the freezer compartment  2  and the refrigerator compartment  3  returns to the evaporator  5  via vent holes  13  and  14 . Accordingly, as the in-refrigerator fan  6  rotates at a high speed, the cool air in the freezer compartment  2  and the refrigerator compartment  3  easily circulates in the refrigerator. In addition, as the in-refrigerator fan  6  rotates at a low speed, the cool air in the freezer compartment  2  and the refrigerator compartment  3  hardly circulates inside the refrigerator. 
     An outside air temperature sensor  7  is provided on an upper surface of the refrigerator  1 . The outside air temperature sensor  7  detects (measures) an outside air temperature of the refrigerator  1 . A location of the outside air temperature sensor is not limited to this and the outside air temperature sensor may be provided on a back surface or a side surface of the refrigerator  1 . In addition, the freezer compartment  2  and the refrigerator compartment  3  each have in-refrigerator temperature sensors  8  and  9  provided inside the refrigerator. In the present embodiment, a control device included in the refrigerator  1  controls an operation and stoppage of the compressor, based on an in-refrigerator temperature of the freezer compartment  2  detected (measured) by the in-refrigerator temperature sensor  8  of the freezer compartment  2 . Thereby, the temperature of the freezer compartment is maintained within a predetermined temperature range. The control of the refrigerator  1  made by the control device will be described below with reference to  FIGS. 2 and 3 . 
       FIG. 2  is a diagram illustrating a functional block of a control device of a refrigerator according to an embodiment of the present disclosure. The control device  10  is installed on an upper portion or a back surface of the refrigerator  1 . The control device  10  may be configured by, for example, a microcomputer, a microprocessor unit or the like, or may be configured by updatable device such as firmware or may be configured by a program or the like executed by a command from a CPU or the like. That is, the control device  10  may have a program for allowing the computer to function as each unit. 
     The control device  10  includes a control unit  101 , a storage unit  102 , and a calculation unit  103 . The control device  10  is connected to the compressor  4 , the in-refrigerator fan  6 , the outside air temperature sensor  7 , the in-refrigerator temperature sensors  8  and  9 , and the like. Detection signals from the outside air temperature sensor  7  and the in-refrigerator temperature sensors  8  and  9  are input to the control device  10 , respectively. The outside air temperature sensor  7  detects an outside air temperature of the refrigerator  1 . The in-refrigerator temperature sensor  8  detects an in-refrigerator temperature of the freezer compartment  2 . The in-refrigerator temperature sensor  9  detects an in-refrigerator temperature of the refrigerator compartment  3 . 
     The control unit  101  controls the compressor  4  and the in-refrigerator fan  6  of the refrigerator  1  based on a control program previously stored in the storage unit  102 . Specifically, the control unit  101  determines an operation and stoppage of the compressor  4  and the in-refrigerator fan  6  and the number of rotations (rotational speed) of the compressor  4  and the in-refrigerator fan  6  based on the control program. For example, in a case where the control device  10  is a microcomputer, the control unit  101  is a processor core. 
     The storage unit  102  stores a control program in advance and also functions as a work area of the control unit  101 . In addition, the storage unit  102  stores detection signals input from the outside air temperature sensor  7  and the in-refrigerator temperature sensors  8  and  9 . 
     The calculation unit  103  calculates an average temperature of the refrigerator compartment  3  during one cycle from when the compressor  4  stops an operation until when the compressor stops a next operation, using an in-refrigerator temperature of the refrigerator compartment  3  stored in the storage unit  102 . Specifically, the calculation unit  103  calculates. In the present embodiment, the calculation unit calculates an average temperature of the refrigerator compartment  3  by using the in-refrigerator temperature of the refrigerator compartment  3  for each unit time during one cycle from when the compressor  4  stops an operation until when the compressor stops a next operation, among the in-refrigerator temperatures of the refrigerator compartment  3  detected by the in-refrigerator temperature sensor  9  and stored in the storage unit  102 . In the present embodiment, the calculation unit calculates the average temperature of the refrigerator compartment  3  during one cycle from when the compressor  4  stops an operation until when the compressor stops a next operation, but a period for calculating the average temperature is not limited to this. For example, the period may be a period from start of the operation of the compressor  4  to stoppage of the compressor  4 , or may be a period from the start of operation of the compressor  4  to start of the next operation. 
     In addition, in the present embodiment, the calculation unit  103  calculates an average temperature of the refrigerator compartment  3 , but the present disclosure is not limited to this. In a case where the control device included in the refrigerator  1  controls an operation and stoppage of the compressor based on the in-refrigerator temperature of the refrigerator compartment  3  detected (measured) by the in-refrigerator temperature sensor  9  included in the refrigerator compartment  3 , by calculation unit  103  may calculate the average temperature of the freezer compartment  2 . In addition, the calculation unit  103  may calculate the average temperatures of the freezer compartment  2  and the refrigerator compartment  3 , respectively. The average temperature calculated by the calculation unit  103  is stored in the storage unit  102 . 
     Next, an operation of the control device according to the present embodiment will be described. The control unit  101  of the control device  10  controls the operations and stoppages of the compressor  4  and the in-refrigerator fan  6  based on the in-refrigerator temperature of the freezer compartment  2 . Specifically, in a case where the in-refrigerator temperature of the freezer compartment  2  is higher than −18° C., the control unit  101  starts the operations of the compressor  4  and the in-refrigerator fan  6 . In addition, in a case where the in-refrigerator temperature of the freezer compartment  2  is lower than −22° C., the control unit  101  stops the operations of the compressor  4  and the in-refrigerator fan  6 . 
     The control unit  101  changes the number of rotations (rotational speed) at the time of operating the compressor  4  according to a change of an outside air temperature. The storage unit  102  stores a correspondence between the outside air temperature and the rotational speed of the compressor  4  in advance. For example, the storage unit  102  previously stores a correspondence table, such as setting the rotational speed per unit time of the compressor  4  to 2000 rpm in a case where the outside air temperature is 20° C., and setting the rotational speed per unit time of the compressor  4  to 2,500 rpm in a case where the outside air temperature is 25° C. When the compressor  4  operates, the control unit  101  determines the rotational speed of the compressor  4  corresponding to the outside air temperature based on the detection signal input from the outside air temperature sensor  7 . 
     The control unit  101  determines the rotational speed of the in-refrigerator fan  6  according to the rotational speed of the compressor  4 . The storage unit  102  previously stores the correspondence between the rotational speed of the compressor  4  and the rotational speed of the in-refrigerator fan  6 . The rotational speed of the in-refrigerator fan  6  determined according to the rotational speed of the compressor  4  is referred to as a reference rotational speed. In the processing to be described below, the rotational speed of the in-refrigerator fan  6  is corrected from the reference rotational speed. Details thereof will be described with reference to  FIG. 3 . 
       FIG. 3  is a flowchart illustrating processing in which the control device determines the rotational speed of the in-refrigerator fan. In a case where the control device  10  is a microcomputer, the processing performed by the control unit  101  to be described in detail below may be realized by processing of a processor core. After the control unit  101  determines the rotational speed of the compressor  4  according to the outside air temperature, the processing of  FIG. 3  starts. First, the control unit  101  determines whether or not the rotational speed of the compressor  4  is changed from a rotational speed (a previous rotational speed) at the time of operating in a previous cycle (step S 101 ). 
     In a case where the control unit  101  determines that the rotational speed of the compressor  4  is changed from the previous rotational speed, the processing proceeds to step S 102 . The control unit  101  determines the rotational speed of the in-refrigerator fan  6  as a reference rotational speed ω 2  without correction (step S 102 ). Then, the control unit  101  maintains the rotational speed ω 2  of the in-refrigerator fan  6  to operate the in-refrigerator fan until the compressor  4  stops (step S 103 ). That is, in a case where the rotational speed of the compressor  4  changed based on the outside air temperature, the control unit  101  maintains the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates in the next cycle to the reference rotational speed determined according to the rotational speed of the compressor  4 . 
     Thereby, in a case where the control unit  101  changes the rotational speed of the compressor  4  due to the change of the outside air temperature, deviation from a predetermined range of the average temperature (range higher than or equal to the reference temperature T 1  and lower than or equal to the reference temperature T 2 ) of the refrigerator compartment  3  can be removed due to the influence. However, even in a case where the control unit  101  changes the rotational speed of the compressor  4 , an average temperature of the refrigerator compartment  3  may not be determined within a predetermined range. In the present embodiment, the control unit  101  changes the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates in the next cycle, thereby, controls the in-refrigerator temperature of the refrigerator compartment  3  so as to be an appropriate value. 
     Meanwhile, in a case where the control unit  101  determines that the rotational speed of the compressor  4  is not changed from the previous rotational speed in step S 101 , the processing proceeds to step S 104 . The control unit  101  determines whether or not the average temperature of the refrigerator compartment  3  stored in the storage unit  102  is lower than s reference temperature T 1  which is a first threshold. In a case where the control unit  101  determines that the average temperature of the refrigerator compartment  3  is lower than the reference temperature T 1 , the processing proceeds to step S 105 . The control unit  101  decreases the rotational speed of the in-refrigerator fan  6  (step S 105 ). That is, the control unit  101  determines the rotational speed of the in-refrigerator fan  6  as ω 1  which is smaller than the reference rotational speed ω 2 . Then, the control unit  101  maintains the rotational speed ω 1  of the in-refrigerator fan  6  to operate the in-refrigerator fan until the compressor  4  stops (step S 106 ). 
     Meanwhile, in a case where the control unit  101  determines that the average temperature of the refrigerator compartment  3  is higher than or equal to the reference temperature T 1  in step S 104 , the processing proceeds to step S 107 . The control unit  101  determines whether or not the average temperature of the refrigerator compartment  3  is higher than a reference temperature T 2  which is a second threshold. The reference temperature T 2  is set to a value larger than the reference temperature T 1 . In a case where the control unit  101  determines that the average temperature of the refrigerator compartment  3  is higher than the reference temperature T 2 , the processing proceeds to step S 108 . The control unit  101  increases the rotational speed of the in-refrigerator fan  6  (step S 108 ). That is, the control unit  101  determines the rotational speed of the in-refrigerator fan  6  as ω 3  which is larger than the reference rotational speed ω 2 . Then, the control unit  101  maintains the rotational speed ω 3  of the in-refrigerator fan  6  to operate the in-refrigerator fan until the compressor  4  stops (step S 109 ). 
     In step S 107 , in a case where the control unit  101  determines that the average temperature of the refrigerator compartment  3  is lower than or equal to the reference temperature T 2 , the processing proceeds to step S 110 . The control unit  101  determines the rotational speed of the in-refrigerator fan  6  as the reference rotational speed ω 2  without correction (step S 110 ). Then, the control unit  101  maintains the rotational speed ω 2  of the in-refrigerator fan  6  to operate the in-refrigerator fan until the compressor  4  stops (step S 111 ). 
     The control unit  101  determines the reference rotational speed ω 2  of the in-refrigerator fan  6  determined according to the rotational speed of the compressor  4 , and correction values thereof ω 1  and ω 3  by using a control sequence not illustrated. A specific value depends on a capacity of the refrigerator  1  and a capacity of the compressor  4 , and it is possible to set an optimum value by actually performing a measurement for each combination of the refrigerator  1  and the compressor  4 . 
     In addition, in a case where it is determined that the average temperature of the refrigerator compartment  3  is higher than or equal to the reference temperature T 1  and is lower than or equal to the reference temperature T 2  (No in step S 104  and No in step S 107 ), the control unit  101  may determine whether or not the outside air temperature tends to increase. At this time, in a case where the control unit  101  determines that the outside air temperature does not increase, the processing proceeds to step S 110 . In a case where the control unit  101  determines that the outside air temperature tends to increase, the control unit  101  determines the rotational speed of the in-refrigerator fan  6  to a value ω 3  which is larger than the reference rotational speed ω 2 . 
     That is, even in a case where the average temperature of the refrigerator compartment  3  is higher than or equal to the reference temperature T 1  which is the first threshold and is lower than or equal to the reference temperature T 2  which is the second threshold, when the outside air temperature tends to increase, the control unit  101  makes the next determination. That is, the control unit  101  increases the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle to a value larger than the reference rotational speed ω 2 . Here, in a case where the outside air temperature tends to increase, the refrigerator compartment  3  is larger in a ratio of the amount of heat leakage than the freezer compartment  2 . That is, the refrigerator compartment  3  is hard to cool as compared with the freezer compartment  2 . In the present embodiment, since the rotational speed of the in-refrigerator fan  6  is higher than the reference rotational speed ω 2 , internal cool air of the refrigerator is further circulated. As a result, since the cool air in the freezer compartment  2  is circulated by the refrigerator compartment  3 , the ratio of the amount of heat leakage can be kept as equal as possible. Accordingly, in a case where the compressor  4  operates and stops based on the in-refrigerator temperature of the freezer compartment  2 , it is possible to prevent the refrigerator compartment  3  from being insufficiently cooled. 
     In the same manner, in a case where it is determined that the average temperature of the refrigerator compartment  3  is higher than or equal to the reference temperature T 1  and is lower than or equal to the reference temperature T 2  (No in step S 104  and No in step S 107 ), the control unit  101  may furthermore determine whether or not the outside air temperature tends to decrease. At this time, in a case where the control unit  101  determines that the outside air temperature does not tend to decrease, the processing proceeds to step S 110 . In a case where the control unit  101  determines that the outside air temperature tends to decrease, the control unit  101  determines the rotational speed of the in-refrigerator fan  6  as ω 1  which is a value smaller than the reference rotational speed ω 2 . 
     That is, even in a case where the average temperature of the refrigerator compartment  3  is higher than or equal to the reference temperature T 1  which is the first threshold and is lower than or equal to the reference temperature T 2  which is the second threshold, when the outside air temperature tends to decrease, the control unit  101  makes the next determination. That is, the control unit  101  decreases the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle to a value lower than the reference rotational speed ω 2 . Thereby, even in a case where it is determined that the rotational speed of the in-refrigerator fan  6  may not be corrected from the average temperature of the refrigerator compartment  3  during the previous cycle of the compressor  4 , in a case where the outside air temperature tends to decrease, the rotational speed of the in-refrigerator fan  6  is decreased. This is because the refrigerator compartment  3  is smaller in the ratio of the amount of heat leakage than the freezer compartment  2  in a case where the outside air temperature tends to decrease. That is, the refrigerator compartment  3  is cooled more easily than the freezer compartment  2 . Accordingly, in a case where the compressor  4  operates and stops based on the in-refrigerator temperature of the freezer compartment  2 , cooling of the refrigerator compartment  3  may be extremely advanced. Therefore, it is possible to suppress overcooling of the refrigerator compartment  3  by decreasing the rotational speed of the in-refrigerator fan  6 . 
     As described above, according to the present embodiment, the control unit  101  corrects the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle, based on the comparison result between the average temperature of the refrigerator compartment  3  and the threshold (the first threshold or the second threshold). Specifically, in a case where the average temperature of the refrigerator compartment  3  is lower than the reference temperature T 1  which is the first threshold, the control unit  101  decreases the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle to a value smaller than the reference rotational speed ω 2 . In addition, in a case where the average temperature of the refrigerator compartment  3  is higher than the reference temperature T 2  which is the second threshold larger than the reference temperature T 1  that is the first threshold, the control unit  101  increases the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle to a value larger than the reference rotational speed ω 2 . 
     That is, in a case where the operation and stop of the compressor  4  are controlled based on the in-refrigerator temperature of the freezer compartment  2  which is the first storage compartment, and in a case where the average temperature of the refrigerator compartment  3  which is the second storage compartment is not fit within a predetermined range (range higher than or equal to the reference temperature T 1  and lower than or equal to the reference temperature T 2 ), the rotational speed of the in-refrigerator fan  6  is corrected. Thereby, it is possible to suppress overcooling and insufficient cooling of the refrigerator compartment  3  even in a case where a cooling method of the individual storage compartments changes relatively depending on contents or quantity in each storage compartment and an opening and closing situation of each storage compartment, and to reduce energy consumption of the refrigerator  1 . 
     In the present embodiment, the first storage compartment is set as the freezer compartment  2 , and the operation and stoppage of the compressor  4  and the in-refrigerator fan  6  are controlled based on the temperature of the freezer compartment  2 , but the present disclosure is not limited to this. The first storage compartment may be set as the refrigerator compartment  3 , and the operation and stoppage of the compressor  4  and the in-refrigerator fan  6  may be controlled based on the temperature of the refrigerator compartment  3 . At this time, in a case where the second storage compartment is set as the freezer compartment  2  and the average temperature of the freezer compartment  2  deviates from the reference temperature, the control unit  101  corrects the rotational speed of the in-refrigerator fan  6  from the reference rotational speed. 
     Here, in a case where the operation and stoppage of the compressor  4  and the in-refrigerator fan  6  are controlled based on the in-refrigerator temperature of the refrigerator compartment  3  rather than the freezer compartment  2 , the calculation unit  103  calculates an average temperature of the freezer compartment  2  during one cycle from when the compressor  4  stops an operation until when the compressor stops a next operation. Then, the calculation unit  103  stores the average temperature of the freezer compartment  2  in the storage unit  102 . In addition, the control unit  101  may replace the “refrigerator compartment” with the “freezer compartment” in the flowchart of  FIG. 3  to perform an operation. At this time, the reference temperatures T 1  and T 2  indicate reference temperatures of a freezer compartment, and the rotational speeds ω 1  to ω 3  of the in-refrigerator compartment fan  6  become ω 1 &gt;ω 2 &gt;ω 3 . 
     That is, in a case where the average temperature of the freezer compartment  2  is lower than the reference temperature T 1  that is a first threshold, the control unit  101  increases the rotational speed of the in-refrigerator fan  6  when the compressor operates during the next cycle to a value larger than the reference rotational speed ω 2 . In a case where the average temperature of the freezer compartment  2  is higher than the reference temperature T 2  which is a second threshold higher than the reference temperature T 1  which is the first threshold, the control unit  101  decreases the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle to a value smaller than the reference rotational speed ω 2 . Thereby, it is possible to suppress overcooling and insufficient cooling of the freezer compartment  2  and to reduce energy consumption of the refrigerator  1 . 
     As described above, according to the present embodiment, in the refrigerator  1  including the first storage compartment and the second storage compartment, the control device  10  that controls the compressor  4  and the in-refrigerator fan  6  for circulating cool air in the refrigerator  1  includes the control unit  101  that controls the rotational speeds of the compressor  4  and the in-refrigerator fan  6  based on an outside air temperature of the refrigerator  1 . In addition, the control device  10  includes the calculation unit  103  that calculates an internal average temperature of the second storage compartment during a predetermined cycle of the compressor  4 . The control unit  101  controls the operation and stoppage of the compressor  4  based on an internal temperature of the first storage compartment. Then, the control unit  101  corrects the rotational speed of the in-refrigerator fan  6  when the compressor  4  operates during the next cycle, based on a comparison result between the average temperature and the threshold (the first threshold or the second threshold). 
     That is, in the refrigerator, even in a case where the operation and stoppage of the compressor are controlled based on the temperature of any one storage compartment (first storage compartment) of the freezer compartment and the refrigerator compartment, an average temperature of the other storage compartment (second storage compartment) is calculated, and the rotational speed of the in-refrigerator fan is corrected based on the average temperature. Therefore, it is possible to suppress overcooling and insufficient cooling also in both the first storage compartment and the second storage compartment. That is, in the refrigerator, it is possible to suppress overcooling or insufficient cooling of the refrigerator compartment and the freezer compartment and to reduce energy consumption of the refrigerator. 
     While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.