Cooling storage

Abstract

To reduce power consumption.SOLUTION: A control part 17 of a cooling storage 10 executes cooling operation for cooling a storage chamber 12 by operating a compressor 27 and a circulation fan 30 when a detection temperature of an inside temperature sensor 36 rises and reaches a set upper limit temperature, and stopping the compressor 27 and the circulation fan 30 when the detection temperature of the inside temperature sensor 36 falls and reaches a set lower limit temperature. When the opening / closing of a door 13 is detected by a door sensor 14 during the stop of a compressor 27 and a circulation fan 30 in a cooling operation, a control part 17 operates the circulation fan 30, and executes door opening / closing time processing for continuing the stop state of the compressor 27.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present technology relates to refrigerated storage. [Background technology]

[0002] Conventionally, in refrigerated storage cabinets, in order to maintain the internal temperature within a preset temperature range, when the internal temperature rises above a preset upper limit temperature, the compressor constituting the cooling device and the internal fan circulating the air inside the cabinet are activated to lower the internal temperature, while when the internal temperature falls below a preset lower limit temperature, the compressor and the internal fan are stopped. Patent Document 1 describes a control method for operating the internal fan with a delay of a predetermined time (e.g., 5 seconds) when the door is opened or closed during such a cooling operation, causing the internal temperature to rise due to warm air flowing in from outside, causing the compressor to operate. This control method prevents the internal pressure from becoming negative due to the warm air being cooled and suddenly contracting. This also prevents the door from becoming difficult to open when trying to reopen it. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-167855 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional cooling operation, when the door is opened or closed, the internal temperature rises due to warm air flowing in from outside the cabinet, causing the compressor and internal fan to operate. This can cause the internal temperature to drop to the set lower limit in a very short time. For example, if the refrigerated storage cabinet contains a large amount of stored items, the cold energy generated by the items is so great that operating the compressor and internal fan can cause the internal temperature to drop in a very short time. Because the compressor consumes a lot of power when it is started, even for such short-term operation, increasing the number of times the compressor is started results in correspondingly increased power consumption. In other words, in conventional cooling operation, increasing the number of times the compressor is started due to door opening or closing results in correspondingly increased power consumption.

[0005] The present technology has been made in consideration of the above-described circumstances, and aims to reduce power consumption. [Means for solving the problem]

[0006] In order to solve the above problems, a refrigerated storage cabinet according to the present technology includes a storage cabinet body having an opening and a storage chamber through which stored items are taken in and out, a door that opens and closes the opening, a cooling device that cools the storage chamber, a circulation fan that circulates air within the storage chamber so that air that has been sucked in from the storage chamber and cooled by a cooler that constitutes the cooling device is returned to the storage chamber, a door sensor that detects whether the door is opened or closed, an internal temperature sensor that detects the temperature of the storage chamber, and a control unit, wherein the control unit executes a cooling operation to cool the storage chamber by activating a compressor and the circulation fan that constitute the cooling device when the temperature detected by the internal temperature sensor rises to a set upper limit temperature, and by stopping the compressor and the circulation fan when the temperature detected by the internal temperature sensor falls to a set lower limit temperature, and when the door sensor detects whether the door is opened or closed during the cooling operation while the compressor and the circulation fan are stopped, the control unit executes a door opening / closing process in which the circulation fan is activated while the compressor remains stopped.

[0007] The door opening / closing process may also include a determination step of determining whether the detected temperature of the internal temperature sensor is equal to or higher than a first threshold temperature when the door sensor detects that the open door has been closed while the compressor and the circulation fan are stopped during the cooling operation, and an operation step of operating the circulation fan if the detected temperature is equal to or higher than the first threshold temperature in the determination step.

[0008] In addition, after the circulation fan is operated in the operation step, if the detected temperature of the internal temperature sensor becomes less than a second threshold temperature, the control unit may stop the circulation fan and terminate the door opening / closing process.

[0009] In addition, after the circulation fan is activated by the activation step, if the detected temperature of the internal temperature sensor becomes equal to or higher than the set upper limit temperature, the control unit may terminate the door opening / closing process while keeping the circulation fan activated.

[0010] In addition, the door opening / closing process may include an operation step of activating the circulation fan when the door sensor detects that the open door has been closed while the compressor and the circulation fan are stopped during the cooling operation.

[0011] In addition, the control unit may operate the circulation fan in the operation step, count the passage of a predetermined time, and when the detected temperature of the internal temperature sensor becomes equal to or lower than a threshold temperature, stop the circulation fan and terminate the door opening / closing process.

[0012] The control unit may also store the opening and closing of the door detected by the door sensor, and when the detected temperature of the internal temperature sensor reaches the set upper limit temperature, determine whether the door was opened or closed while the detected temperature of the internal temperature sensor was between the set lower limit temperature and the set upper limit temperature, and perform the door opening / closing processing if the door was opened or closed. [Effects of the Invention]

[0013] According to this technology, power consumption can be reduced. [Brief explanation of the drawings]

[0014] [Figure 1] Partially cutaway perspective view of a prefabricated refrigerator according to the first embodiment [Figure 2] Schematic cross-sectional view of the indoor unit [Figure 3] Flowchart showing the process when the door is opened and closed during cooling operation [Figure 4] Timing chart for when door opening / closing process is executed (Example 1) [Figure 5] Timing chart for when door opening / closing process is executed (Example 2) [Figure 6] Timing chart when door opening / closing process is not executed (Comparative Example 1) [Figure 7] 10 is a flowchart showing a process when the door is opened and closed during a cooling operation according to a second embodiment. [Figure 8] Timing chart for when door opening / closing process is executed (Example 3) [Figure 9] Timing chart when door opening / closing process is not executed (Comparative Example 2) [Figure 10] 10 is a flowchart showing a process when the door is opened and closed during a cooling operation according to a third embodiment. [Figure 11] Timing chart for when door opening / closing process is executed (Example 4) [Figure 12] 10 is a flowchart showing a process when the door is opened and closed during the cooling operation according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] <Embodiment 1> A refrigerated storage cabinet 10 according to a first embodiment will be described with reference to Figures 1 to 5. The symbols F, B, L, R, U, and D shown in some of the drawings respectively indicate the front and rear in the front-to-rear direction of the refrigerated storage cabinet 10, the left and right in the width direction (left-right direction) when viewed from the front, and the top and bottom in the vertical direction (up-down direction).

[0016] As shown in FIG. 1 , the refrigerated storage cabinet 10 mainly comprises a storage cabinet main body 11, an insulated door 13, a cooling device 20 for cooling a storage chamber 12 that occupies most of the interior space of the storage cabinet main body 11, a control unit 17, and an operation unit 18. The storage cabinet main body 11 is an insulated box body formed by assembling insulated walls into a box shape and has a front opening 11S. The door 13 is attached to the front wall of the storage cabinet main body 11 so that the front opening 11S can be swung open and closed. The refrigerated storage cabinet 10 also has a door sensor 14 located near the upper edge of the front opening 11S that detects whether the door 13 is open or closed. The type of door sensor 14 is not limited, but it can be, for example, a proximity switch that responds to a magnet embedded in the door 13. If the door sensor 14 is a proximity switch, the switch turns on and off depending on whether the door 13 is open or closed.

[0017] The front opening 11S and the door 13 according to this embodiment are large enough for a person to enter and exit to take stored items in and out, and the refrigerated storage facility 10 is a prefabricated refrigerated storage facility with a large storage room 12. However, this technology can also be applied to refrigerated storage facilities other than prefabricated facilities that are not large in size.

[0018] Inside the storage body 11 (hereinafter sometimes referred to as the inside of the storage body), an indoor unit 15 incorporating a cooler 25 and an interior fan 30 (an example of a circulation fan) described below is disposed in a manner that it is suspended from the ceiling wall 11A of the storage body 11. Most of the space inside the storage body 11 other than the space where the indoor unit 15 is disposed is a storage room 12. Outside the storage body 11 (hereinafter sometimes referred to as the outside of the storage body), an outdoor unit 16 connected to the cooler 25 by refrigerant piping 29 is installed.

[0019] The outdoor unit 16 includes at least a compressor 27 and an air-cooled condenser 28. The cooler 25, compressor 27, and condenser 28 are connected by refrigerant piping 29 to form a known refrigeration circuit, which constitutes the cooling device 20. The cooler 25 is a fin-tube heat exchanger. The cooling device 20 is further provided with a dryer and the like as appropriate.

[0020] The control unit 17 is configured with a control board including a CPU, a microcomputer, etc., and controls the operation of the cooling storage cabinet 10. The control unit 17 is equipped with memories such as ROM and RAM, and has a time counting function (timer). The operation unit 18 is provided to allow the user to change various settings of the cooling storage cabinet 10 and select an operation mode.

[0021] As shown in Fig. 2, the indoor unit 15 includes a cooler 25, an internal fan 30, a cooler temperature sensor 35, an internal temperature sensor 36, a defrosting heater 37, and a casing 38 in which these components are housed and attached. The casing 38 has a rectangular parallelepiped shape that is elongated in the front-to-rear direction, and an air inlet 38A for the storage chamber 12 is formed over almost the entire surface of one side surface (the right side in Fig. 2).

[0022] Cooler 25 is disposed on the side of suction port 38A inside casing 38. An internal temperature sensor 36 (e.g., a thermistor) is attached near suction port 38A to detect the temperature of the air in storage chamber 12 flowing into cooler 25. Casing 38 also serves as a drain pan to receive defrosted water that drops from cooler 25. The bottom surface of casing 38 is inclined, and drain port 38B is provided at the lower edge of the bottom surface to which drain hose 39 (see FIG. 1) is connected.

[0023] The internal fan 30 is provided inside the casing 38 on the opposite side of the intake port 38A, and is disposed adjacent to the cooler 25. The internal fan 30 includes a main body 31 that rotates when driven by a motor, and a fan cover 32 that covers the main body 31.

[0024] The fan cover 32 of the internal fan 30 is attached so as to cover an opening 38C on the other side (the left side in FIG. 2 ) of the casing 38. A vent hole is formed in the fan cover 32, which serves as an outlet 32A for cold air to be blown into the storage chamber 12. The fan cover 32 may be formed as a part of the casing 38, and the outlet 32A may be a vent hole formed in the casing 38.

[0025] Main body 31 of internal fan 30 rotates to draw in cool air from cooler 25 and blow the drawn-in cool air out of outlet 32A. Therefore, internal fan 30 circulates air in storage chamber 12 such that air is drawn from storage chamber 12 through inlet 38A into cooler 25, cooled by cooler 25, and then blown out of outlet 32A and returned to storage chamber 12.

[0026] Defrosting heater 37 heats and melts frost adhering to cooler 25 and the like during defrosting operation, which will be described later. Defrosting heater 37 is, for example, a sheathed heater, and is attached to the surface of cooler 25 on the side of inlet 38A and to the bottom surface. More specifically, defrosting heater 37 is fitted into grooves 25A formed by cutting out the edges of the fins and end plates of cooler 25, and is disposed so as to be wound in a serpentine shape.

[0027] The cooler temperature sensor 35 (e.g., a thermistor) detects the temperature of the cooler 25. The cooler temperature sensor 35 according to this embodiment is provided at a position away from the air inlet 38A side (air inflow side) of the cooler 25, for example, by being attached to an end plate of the cooler 25. The location of the cooler temperature sensor 35 is not particularly limited as long as it can detect the temperature of the cooler 25.

[0028] Next, the operation control of the refrigerated storage cabinet 10 configured as described above will be described. The control unit 17 executes a cooling operation to cool the storage chamber 12 by operating the compressor 27 (cooling device 20) and the internal fan 30. During the cooling operation, air in the storage chamber 12 drawn in through the intake port 38A of the casing 38 becomes cold air through heat exchange while passing through the cooler 25, and this cold air is blown out into the storage chamber 12 from the outlet port 32A. The air circulates in this manner, thereby cooling the storage chamber 12.

[0029] During normal cooling operation when the door 13 is not opened or closed, if the temperature inside the storage compartment 12 detected by the internal temperature sensor 36 (hereinafter sometimes referred to as the internal temperature) falls to an internal set lower limit temperature Tmin (for example, a temperature ΔT (3°C) lower than the internal set temperature Ts), the control unit 17 stops the operation of the compressor 27 and the internal fan 30. On the other hand, if the internal temperature rises to an internal set upper limit temperature Tmax (for example, a temperature ΔT (3°C) higher than the internal set temperature Ts), the control unit 17 operates the compressor 27 and the internal fan 30. This keeps the temperature inside the storage compartment 12 within a range from the internal set lower limit temperature Tmin to the internal set upper limit temperature Tmax.

[0030] Therefore, during normal cooling operation, the control unit 17 synchronizes the operation and stopping of the compressor 27 and the internal fan 30. However, the operation and stopping timing of the compressor 27 and the internal fan 30 when they are synchronized does not have to match perfectly, and as described in Patent Document 1, for example, a case in which the internal fan 30 starts operating with a delay from the operation of the compressor 27 is also considered to be included in the synchronized control. Furthermore, the operation of the internal fan 30 while the compressor 27 is stopped may be an intermittent operation that repeats on and off at a predetermined cycle.

[0031] Furthermore, the control unit 17 performs a defrosting operation at predetermined cooling operation times, etc. With the compressor 27 and the internal fan 30 stopped, the control unit 17 applies power to the defrosting heater 37 to heat the cooler 25, thereby melting and defrosting the frost adhering to the cooler 25. The defrost water generated by the melting is received on the bottom surface of the casing 38, and then flows down the drain hose 39 to be drained outside the cooler. The control unit 17 ends the defrosting operation when the temperature detected by the cooler temperature sensor 35 reaches the defrost completion temperature.

[0032] Furthermore, when the control unit 17 controls the operation and stopping of the compressor 27 and the internal fan 30 in conjunction with each other based on the internal set lower limit temperature Tmin and the internal set upper limit temperature Tmax during the normal cooling operation described above, if the door 13 is opened or closed while the compressor 27 and the internal fan 30 are stopped, the control unit 17 executes a door opening / closing process in which only the internal fan 30 is operated and the compressor 27 remains stopped. The door opening / closing process will be described below with reference to the flowchart in Figure 3. The first and second threshold temperatures in the flowchart can be set arbitrarily, but in this embodiment, both are set to the same temperature as the internal set temperature Ts.

[0033] During the normal cooling operation described above, when the door sensor 14 detects that the door 13 has been opened while the compressor 27 and the internal fan 30 are stopped, the control unit 17 interrupts and starts the door opening / closing process as needed (S10). When the door sensor 14 detects that the opened door 13 has been closed (YES in S20), the control unit 17 determines whether the temperature detected by the internal temperature sensor 36 (internal temperature) is equal to or higher than a preset first threshold temperature (S25, determination step).

[0034] If the result of the determination is that the internal temperature is equal to or higher than the first threshold temperature (YES in S25), the control unit 17 operates only the internal fan 30 (S30, operation step), and keeps the compressor 27 stopped. On the other hand, if the internal temperature is lower than the first threshold temperature (NO in S25), the door opening / closing process ends (returns to normal cooling operation).

[0035] If the internal temperature falls below the second threshold temperature after the internal fan 30 is activated (NO in S35), the control unit 17 stops the internal fan 30 (S40) and ends the door opening / closing process (returns to normal cooling operation). On the other hand, if the internal temperature is equal to or higher than the second threshold (YES in S35), the control unit 17 determines whether the internal temperature has risen to or above the internal upper limit temperature Tmax (S45). If the internal temperature is below the internal upper limit temperature Tmax, the control unit 17 continues to operate the internal fan 30 while the internal temperature is equal to or higher than the second threshold (NO in S45). If the internal temperature has risen to or above the internal upper limit temperature Tmax (YES in S45), the control unit 17 ends the door opening / closing process (returns to normal cooling operation). Because the internal temperature has risen to or above the internal upper limit temperature Tmax at this time, both the compressor 27 and the internal fan 30 start operating when the system returns to normal cooling operation.

[0036] Next, the effects of the door opening / closing process described above will be explained with reference to timing charts of Example 1 in Fig. 4 and Example 2 in Fig. 5, and in comparison with the timing chart of Comparative Example 1 in Fig. 6. Figs. 4 and 5 are timing charts during cooling operation when the door opening / closing process (the first threshold temperature and the second threshold temperature are both set to the internal temperature Ts) is executed. Fig. 4 shows a case where the amount of stored items in storage chamber 12 is large (Example 1), and Fig. 5 shows a case where the amount of stored items in storage chamber 12 is small (Example 2).

[0037] First, the timing chart of Figure 4 (Example 1) will be described. In Figure 4, normal cooling operation is performed during the time period before door 13 is opened (before time t2). Therefore, compressor 27 and internal fan 30 both operate (ON) until time t1 when the internal temperature drops to the internal set lower limit temperature Tmin, and at time t1 when the internal set lower limit temperature Tmin is reached, both compressor 27 and internal fan 30 stop (OFF).

[0038] After time t1, when compressor 27 and internal fan 30 are stopped, the internal temperature gradually rises. Then, when door 13 is opened while compressor 27 and internal fan 30 are stopped (time t2), the internal opening / closing process described above is initiated (S10 in FIG. 3). Furthermore, because warm air flows in from outside the cabinet when door 13 is opened, the rate at which the internal temperature rises increases after time t2. Then, when door 13 is closed (time t3), it is determined whether the internal temperature is equal to or higher than a first threshold temperature (internal set temperature Ts) (S25 in FIG. 3). If the internal temperature is equal to or higher than the first threshold temperature, only internal fan 30 operates, and compressor 27 remains stopped (S30 in FIG. 3, between times t3 and t4 in FIG. 4).

[0039] When the internal fan 30 operates, in Example 1 of Figure 4, it is assumed that the storage compartment 12 contains a large amount of stored items. Therefore, the cold heat from the stored items cools the storage compartment 12, and the internal temperature drops from time t3 onwards. Then, when the internal temperature drops below the second threshold temperature (set internal temperature Ts) at time t4, the internal fan 30 that was operating is stopped (S40 in Figure 3), and the door opening / closing process is terminated (returning to normal cooling operation). Since normal cooling operation is performed from time t4 onwards, both the internal fan 30 and the compressor 27 are stopped until the internal temperature rises to the set internal upper limit temperature Tmax. When the internal temperature reaches the set internal upper limit temperature Tmax (time t5), both the internal fan 30 and the compressor 27 operate.

[0040] In this way, when the door 13 is opened or closed, the internal fan 30 is operated to circulate the cold heat from the amount of stored goods, thereby suppressing the rise in the temperature inside the cabinet, while the compressor 27 continues to be stopped, thereby reducing the power consumption associated with starting the compressor.

[0041] In contrast, when the door opening / closing process is not executed (Comparative Example 1), normal cooling operation is performed, as shown in the timing chart in Figure 6. In Figure 6, door 13 is opened while the internal fan 30 and compressor 27 are stopped, and when the open door 13 is closed and the internal temperature rises to the internal set upper limit temperature Tmax (time t6), both the internal fan 30 and compressor 27 start operating. This operation also causes the internal temperature to drop sharply, and the internal temperature falls to the internal set lower limit temperature Tmin in an extremely short time (time t7). As a result, both the internal fan 30 and compressor 27 stop again in a short time. Then, when the internal temperature rises to the internal set upper limit temperature Tmax due to the shutdown (time t8), both the internal fan 30 and compressor 27 start operating again.

[0042] Comparing the timing charts of Example 1 in Fig. 4 and Comparative Example 1 in Fig. 6, it can be seen that the number of times that compressor 27 is started is reduced by executing the door opening / closing process. More specifically, during the illustrated period, the number of times that compressor 27 is started is two, at times t6 and t8, in Comparative Example 1 in Fig. 6, whereas it is reduced to only one, at time t5, in Example 1 in Fig. 4. Therefore, according to the door opening / closing process of this embodiment, the number of times that compressor 27 is started is reduced, thereby reducing power consumption and extending the life of compressor 27.

[0043] Furthermore, in the door opening / closing process, a determination as to whether or not to operate the internal fan 30 is made when the door 13 is closed (YES in S20, S25 in FIG. 3). Therefore, the internal fan 30 remains stopped while the door 13 is open, and the inflow of outside air through the open door 13 is suppressed.

[0044] Next, a description will be given of the timing chart of Fig. 5 (Example 2). In Fig. 5, the changes up to time t3 when the internal fan 30 operates (steps up to S30 in Fig. 3) are the same as those in Example 1, and therefore a description thereof will be omitted.

[0045] After time t3, the internal fan 30 operates, and the cold energy from the stored items cools the storage chamber 12 to a certain degree. However, in Example 2 of FIG. 5, it is assumed that the amount of stored items in the storage chamber 12 is small, and the cold energy is smaller than in Example 1 of FIG. 4. Therefore, the internal temperature does not fall below the second threshold temperature (internal set temperature Ts) (YES in S35 of FIG. 3). After falling to a certain degree until time t10, the internal temperature gradually rises, reaching the internal upper limit temperature Tmax at time t11. While the internal temperature is below the internal upper limit temperature Tmax, only the internal fan 30 continues to operate (NO in S45 of FIG. 3, from time t3 to t11 in FIG. 4).

[0046] When the internal temperature rises to the internal upper limit temperature Tmax at time t11 (YES in S45 of FIG. 3), the door opening / closing process ends (returns to normal cooling operation). Normal cooling operation is performed after time t11, but because the internal temperature has reached the internal set upper limit temperature Tmax at time t11, the internal fan 30 continues to operate and the stopped compressor 27 starts operating. Therefore, after time t11, both the internal fan 30 and the compressor 27 will operate again.

[0047] Comparing the timing charts of Example 2 in Fig. 5 and Comparative Example 1 in Fig. 6, it can be seen that executing the door opening / closing process reduces the number of times that compressor 27 is started. More specifically, during the illustrated period, the number of times that compressor 27 is started is two, at times t6 and t8, in Comparative Example 1 in Fig. 6, whereas it is reduced to only one, at time t11, in Example 2 in Fig. 5. Therefore, power consumption can be reduced by the amount of the reduction in the number of times that compressor 27 is started, and the life of compressor 27 can also be extended.

[0048] <Embodiment 2> The door opening / closing process according to the second embodiment will be described with reference to Fig. 7 and Fig. 8. The second embodiment differs from the first embodiment in that the door opening / closing process is executed as shown in the flowchart of Fig. 7. In the second embodiment, redundant descriptions of the configuration and effects similar to those of the first embodiment will be omitted.

[0049] During normal cooling operation, when the door sensor 14 detects that the door 13 has been opened while the compressor 27 and the internal fan 30 are stopped, the control unit 17 interrupts and starts the door opening / closing process (S10). When the door sensor 14 detects that the open door 13 has been closed (YES in S20), the control unit 17 operates only the internal fan 30 (S50, operation step), and the compressor 27 remains stopped. After the internal fan 30 is operated, the control unit 17 counts the elapsed time (S55) and determines whether the internal temperature is equal to or lower than a third threshold temperature (S60). If the determination indicates that the internal temperature has dropped to or lower than the third threshold temperature (YES in S60), the control unit 17 stops the internal fan 30 (S65) and ends the door opening / closing process (returning to normal cooling operation). The third threshold temperature can be set arbitrarily, but in this embodiment it is set to the same temperature as the internal upper limit temperature Tmax.

[0050] On the other hand, if the temperature exceeds the third threshold temperature (NO in S60), the door opening / closing process is terminated (return to normal cooling operation). When normal cooling operation is resumed, the internal temperature has reached the third threshold temperature (i.e., internal upper limit temperature Tmax), so both compressor 27 and internal fan 30 start operating.

[0051] The effect of the door opening / closing process according to this embodiment will be described with reference to the timing chart of Example 3 in Figure 8, in comparison with the timing chart of Comparative Example 2 in Figure 9. Figure 8 is a timing chart during cooling operation when the door opening / closing process (the third threshold temperature is set to the same temperature as the upper limit internal temperature Tmax) is executed, and Figure 9 is a timing chart during cooling operation when the door opening / closing process is not executed. Figure 8 shows an example (Example 3) in which the opening time from when the door 13 is opened until it is closed is long, and the internal temperature rises to the set upper limit internal temperature Tmax while the door 13 is open.

[0052] In Example 3, for example, it is assumed that work is performed for a long time in storage chamber 12 with door 13 open in order to take in or out a large amount of stored goods. In contrast, in Example 1 of Fig. 4 and Example 2 of Fig. 5 according to the above-described Embodiment 1, the temperature inside the storage chamber does not rise above the set upper limit temperature Tmax while door 13 is open, so it is assumed that work is performed for a short time in storage chamber 12 with door 13 open in order to take out a small amount of stored goods, for example.

[0053] In Figure 8, normal cooling operation is performed during the time period before door 13 is opened (before time t2). Therefore, both compressor 27 and internal fan 30 operate until the internal temperature drops to the internal set lower limit temperature Tmin, and at time t1 when the internal set lower limit temperature Tmin is reached, both compressor 27 and internal fan 30 are stopped.

[0054] In Figure 8, after time t1, compressor 27 and internal fan 30 are stopped, so the internal temperature gradually rises. If door 13 is opened while compressor 27 and internal fan 30 are stopped (time t2), the internal opening / closing process described above is initiated (S10 in Figure 7). Furthermore, because warm air flows in from outside the cabinet when door 13 is opened, the rate at which the internal temperature rises increases after time t2, and the internal temperature reaches the third threshold temperature (internal set upper limit temperature Tmax) while door 13 is open (time t12).

[0055] At this time, because the compartment opening / closing process is being executed, unlike normal cooling operation, the compressor 27 and the compartment fan 30 are not operated at time t12 and remain stopped. Then, when the opened door 13 is closed (time t13), only the compartment fan 30 is operated, and the compressor 27 remains stopped (S50 in FIG. 7). When the compartment fan 30 is operated, the storage compartment 12 is cooled by the cold heat of the stored items, and the compartment temperature drops from time t13 onwards.

[0056] Then, at time t14 (S55 in FIG. 7), when a predetermined time has elapsed since time t13, if the internal temperature falls below the third threshold temperature (internal set upper limit temperature Tmax), the internal fan 30 that was operating is stopped (S65 in FIG. 7), and the door opening / closing process is terminated (returning to normal cooling operation). Normal cooling operation is performed from time t14 onwards, so both the internal fan 30 and compressor 27 are stopped until the internal temperature rises to the internal set upper limit temperature Tmax, and then at time t15, when the internal set upper limit temperature Tmax is reached, both the internal fan 30 and compressor 27 operate.

[0057] In this way, when the door 13 is opened or closed, the internal fan 30 is operated to circulate the cold heat from the amount of stored goods, thereby suppressing the rise in the temperature inside the cabinet, while the compressor 27 continues to be stopped, thereby reducing the power consumption associated with starting the compressor 27.

[0058] In contrast, when the door opening / closing process is not executed (Comparative Example 2), normal cooling operation is performed, as shown in the timing chart in Figure 9. In Figure 9, door 13 is opened while the internal fan 30 and compressor 27 are stopped, and when the internal temperature rises to the internal set upper limit temperature Tmax (time t12), compressor 27 starts operating. The internal fan 30 is stopped while door 13 is open to prevent outside air from entering, and starts operating when door 13 is closed (time t13). This operation also causes the internal temperature to drop sharply, and the internal temperature drops to the internal set lower limit temperature Tmin in an extremely short time (time t16). As a result, both the internal fan 30 and compressor 27 stop again in a short time. Then, when the internal temperature rises to the internal set upper limit temperature Tmax due to the stopping (time t17), both the internal fan 30 and compressor 27 start operating again.

[0059] Comparing the timing charts of Comparative Example 3 in Fig. 8 and Comparative Example 2 in Fig. 9, it can be seen that the number of times that compressor 27 is started is reduced by executing the door opening / closing process. More specifically, during the illustrated period, the number of times that compressor 27 is started is two, at times t12 and t17, in Comparative Example 2 in Fig. 9, whereas it is reduced to only one, at time t15, in Example 3 in Fig. 8. Therefore, according to the door opening / closing process of this embodiment, the number of times that compressor 27 is started is reduced, thereby reducing power consumption and extending the life of compressor 27.

[0060] <Embodiment 3> The door opening / closing process according to the third embodiment will be described with reference to Fig. 10 and Fig. 11. In the third embodiment, the start conditions for the door opening / closing process are different from those in the first embodiment. In the third embodiment, the same configurations and effects as those in the first embodiment will not be described again.

[0061] The control unit 17 according to this embodiment stores whether or not the door 13 was opened or closed during the period from when the internal temperature reached the internal set lower limit temperature Tmin to when it reached the internal set upper limit temperature Tmax (i.e., during the period from when the operating compressor 27 and internal fan 30 were stopped until they were restarted). Furthermore, as shown in FIG. 10, when the internal temperature reached the internal upper limit temperature Tmax while the compressor 27 and internal fan 30 were stopped (YES in S70), the control unit 17 determines whether or not the opening or closing of the door 13 was stored (S75). If the result shows that the door 13 was opened or closed (YES in S75), the door opening and closing process from step S30 onward in the first embodiment is executed with an interrupt.

[0062] In this way, as shown in the timing chart of FIG. 11 (Example 4), when the door 13 is opened and closed multiple times in a short period of time (for example, when the door 13 is opened and closed to enter the storage compartment 12 and then opened and closed again to leave the storage compartment 12), the internal fan 30 operates at time t18 when the internal temperature reaches the internal upper limit temperature Tmax (S30 in FIG. 10). Unlike the first embodiment, the door opening and closing process is not executed each time the door 13 is opened and closed. This prevents the internal fan 30 from being repeatedly turned on and off, thereby preventing a shortened lifespan of the internal fan 30 and reducing power consumption by the internal fan 30. Therefore, according to this embodiment, it is possible to reduce power consumption and extend the lifespan of the compressor 27 while also preventing power consumption and a shortened lifespan of the internal fan 30.

[0063] <Embodiment 4> The door opening / closing process according to the fourth embodiment will be described with reference to Fig. 12. In the fourth embodiment, the start conditions for the door opening / closing process are different from those in the second embodiment. In the fourth embodiment, the same configurations and effects as those in the first to third embodiments will not be described again.

[0064] 12, when the internal temperature reaches the internal upper limit temperature Tmax while the compressor 27 and the internal fan 30 are stopped (YES in S70), the control unit 17 according to this embodiment determines whether or not opening or closing of the door 13 has been stored (S75), as in the third embodiment. If the door 13 has been opened or closed (YES in S75), the control unit 17 executes the door opening and closing process from step S50 onward in the second embodiment with an interrupt.

[0065] In this way, unlike in embodiment 2, the door opening / closing process is not executed each time the door 13 is opened or closed. When the door 13 is opened and closed multiple times in a short period of time, it is possible to prevent the internal fan 30 from being repeatedly turned on and off each time the door 13 is opened or closed. According to this embodiment, it is possible to reduce the power consumption and extend the life of the compressor 27, while also suppressing the power consumption and shortening the life of the internal fan 30.

[0066] <Other embodiments> The present technology is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments, for example, are also included in the technical scope of the present technology.

[0067] (1) In the door opening / closing process according to the second embodiment, in consideration of the effect on stored items, a determination is made before step S50 as to whether the internal temperature is below a fourth threshold temperature (a predetermined temperature equal to or higher than the internal set upper limit temperature Tmax), and the process proceeds to step S50 only if the internal temperature is below the fourth threshold temperature. If the internal temperature is equal to or higher than the fourth threshold temperature, the door opening / closing process may be terminated and the process may return to normal cooling operation. When the process returns to normal cooling operation, the internal temperature has reached the internal upper limit temperature Tmax, and therefore both compressor 27 and internal fan 30 will start operating. [Explanation of symbols]

[0068] 10: Cooling storage cabinet, 11: Storage cabinet body, 11S: Front opening (opening), 12: Storage room, 13: Door, 14: Door sensor, 17: Control unit, 20: Cooling device, 25: Cooler, 27: Compressor, 30: In-cabinet fan (circulation fan), 36: In-cabinet temperature sensor, Tmax: In-cabinet set upper limit temperature (third threshold temperature), Tmin: In-cabinet set lower limit temperature, Ts: In-cabinet set temperature (first threshold temperature, second threshold temperature)

Claims

1. a storage body having an opening and a storage chamber through which stored items are put in and taken out; a door for opening and closing the opening; a cooling device for cooling the storage chamber; a circulation fan that circulates air in the storage chamber so that the air that has been sucked in from the storage chamber and cooled by a cooler that constitutes the cooling device is returned to the storage chamber; a door sensor that detects whether the door is open or closed; an internal temperature sensor for detecting the temperature of the storage compartment; a control unit, The control unit When the temperature detected by the internal temperature sensor rises and reaches a set upper limit temperature, the compressor and the circulation fan constituting the cooling device are operated, and when the temperature detected by the internal temperature sensor falls and reaches a set lower limit temperature, the compressor and the circulation fan are stopped, thereby performing a cooling operation to cool the storage chamber; When the door sensor detects the opening or closing of the door while the compressor and the circulation fan are stopped during the cooling operation, the cooling storage facility executes a door opening / closing process in which the circulation fan is activated while the compressor remains stopped.

2. The door opening / closing process of the refrigerated storage cabinet of claim 1 includes a determination step of determining whether the detected temperature of the internal temperature sensor is equal to or higher than a first threshold temperature when the door sensor detects that the open door has been closed while the compressor and the circulation fan are stopped during the cooling operation, and an operation step of operating the circulation fan if the detected temperature is equal to or higher than the first threshold temperature in the determination step.

3. The refrigerated storage cabinet of claim 2, wherein the control unit stops the circulation fan and terminates the door opening / closing process when the detected temperature of the internal temperature sensor becomes lower than a second threshold temperature after the circulation fan is activated by the activation step.

4. The refrigerated storage cabinet of claim 2, wherein, after the circulation fan is activated by the activation step, when the detected temperature of the internal temperature sensor becomes equal to or higher than the set upper limit temperature, the control unit terminates the door opening / closing process while keeping the circulation fan activated.

5. The cooling storage facility of claim 1, wherein the door opening / closing process includes an operation step of activating the circulation fan when the door sensor detects that the open door has been closed while the compressor and the circulation fan are stopped during the cooling operation.

6. The refrigerated storage cabinet of claim 5, wherein the control unit operates the circulation fan in the operation step, counts the passage of a predetermined time, and when the detected temperature of the internal temperature sensor becomes equal to or lower than a threshold temperature, stops the circulation fan and terminates the door opening / closing process.

7. The control unit The door sensor detects whether the door is open or closed, and stores the detected opening and closing status of the door. When the detected temperature of the inside temperature sensor reaches the set upper limit temperature, it is determined whether or not the door has been opened or closed while the detected temperature of the inside temperature sensor is between the set lower limit temperature and the set upper limit temperature; The refrigerated storage facility according to any one of claims 1 to 6, wherein the door opening / closing process is executed when the door is opened or closed.

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