Cooling storage box

Abstract

To realize a cooling storage box capable of more securely detecting abnormality of a compressor.SOLUTION: A cooling storage box 10 includes: a storage box body 11; a cooler 38; a compressor 32; a condenser 36; a box temperature sensor 19; a cooler temperature sensor 37; an external temperature sensor 55 detecting an external temperature of the periphery of the storage box body 11; a condenser temperature sensor 35; and a control unit 50 for executing abnormality notification processing of the compressor 32. The abnormality notification processing includes: calculation processing S20 of calculating a cooling temperature difference D37 by subtracting a cooler temperature T37 detected by the cooler temperature sensor 37 from an in-box temperature T19, and calculating a condensate temperature difference D35 by subtracting an external temperature T55 from a condenser temperature T35 detected by the condenser temperature sensor 35; and output processing S30 to S32 of outputting information of notifying abnormality of the compressor 32 when a state that the cooling temperature difference D37 is less than a cooling threshold value Th37 continues for a prescribed time P37 or more, and a state that the condensate temperature difference D35 is less than a condensate threshold value Th35 continues for a prescribed time P35 or more.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] Conventionally, there is known a technology that issues a high temperature abnormality alert when the temperature inside a refrigerated storage facility remains higher than a threshold temperature for a predetermined period of time, and one example of this is described in Patent Document 1. The control unit of the refrigerated storage facility described in Patent Document 1 detects the temperature inside the facility at predetermined intervals using an internal thermistor, and displays an error code on the operation panel when the temperature remains, for example, +10K higher than the set temperature for a predetermined period of time.

[0003] Also, different error codes are displayed depending on whether an error is output from the inverter board of the inverter compressor that constitutes the cooling device. If an error is output from the inverter board, it is possible that the inverter compressor is not operating normally, causing the high temperature abnormality. The cooling storage described in Patent Document 1 is designed to narrow down the general cause of the high temperature abnormality depending on the type of error code displayed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-85409 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, there are cases where the compressor abnormality cannot be detected by the high temperature abnormality detection based on the temperature inside the cabinet as described above. For example, in a large cooling storage cabinet, two cooling devices (two compressors) are sometimes installed to make the temperature inside the cabinet more uniform, and even if one compressor stops abnormally due to a malfunction, if the other compressor is operating normally, the temperature inside the cabinet may not reach the threshold temperature for reporting a high temperature abnormality. In that case, the high temperature abnormality is not reported, and one compressor continues to be used in the malfunctioning state. As a result, there is a concern that the uniformity of the temperature distribution inside the cabinet may decrease, or the cooling speed may decrease, making it difficult to cool the inside of the cabinet.

[0006] The present technology has been developed based on the above-mentioned circumstances, and aims to realize a refrigerated storage facility that can more reliably detect compressor abnormalities. [Means for solving the problem]

[0007] In order to solve the above problems, a cooling storage container according to the present technology includes a storage container body, a cooler into which air drawn from inside the storage container body flows and cools the air passing through the inside, a compressor that compresses refrigerant gas from the cooler, and a condenser that condenses the refrigerant gas from the compressor, and a cooling device having an internal temperature sensor that detects an internal temperature inside the storage container body, a cooler temperature sensor that detects the temperature of the cooler, an external temperature sensor that detects the external temperature around the storage container body, a condenser temperature sensor that detects the temperature of the condenser, and a compressor that compresses the refrigerant gas from the cooler. and a control unit that executes an abnormality notification process that outputs information to notify of an abnormality in the compressor, the abnormality notification process including a calculation process that calculates a cooling temperature difference by subtracting the cooler temperature detected by the cooler temperature sensor from the internal temperature, and a condensation temperature difference by subtracting the external temperature from the condenser temperature detected by the condenser temperature sensor, and an output process that outputs information to notify of an abnormality in the compressor when a state in which the cooling temperature difference is less than a cooling threshold continues for a predetermined time or more and a state in which the condensation temperature difference is less than the condensation threshold continues for a predetermined time or more.

[0008] The compressor may have a variable speed motor, and the control unit may execute the output process when the speed of the motor is set to a value equal to or higher than a median value and equal to or lower than an upper limit value in a variable speed range.

[0009] Further, the cooling device includes a first cooling device and a second cooling device, the first cooling device has a first cooler, a first compressor, and a first condenser, the second cooling device has a second cooler, a second compressor, and a second condenser, the cooler temperature sensor includes a first cooler temperature sensor that detects a temperature of the first cooler and a second cooler temperature sensor that detects a temperature of the second cooler, the condenser temperature sensor includes a first condenser temperature sensor that detects the temperature of the first condenser and a second condenser temperature sensor that detects the temperature of the second condenser, and the calculation process includes subtracting the cooler temperature detected by the first cooler temperature sensor from the internal temperature to calculate a first cooling temperature difference, and subtracting the external temperature from the condenser temperature detected by the first condenser temperature sensor to calculate a first condensing temperature difference. and a second calculation process of calculating a second cooling temperature difference by subtracting the cooler temperature detected by the second cooler temperature sensor from the internal temperature and of calculating a second condensing temperature difference by subtracting the external temperature from the condenser temperature detected by the second condenser temperature sensor, and the output process may include a first output process of outputting information notifying of an abnormality in the first compressor when a state in which the first cooling temperature difference is less than a first cooling threshold value continues for a predetermined time or more and a state in which the first condensing temperature difference is less than the first condensing threshold value continues for a predetermined time or more, and a second output process of outputting information notifying of an abnormality in the second compressor when a state in which the second cooling temperature difference is less than the second cooling threshold value continues for a predetermined time or more and a state in which the second condensing temperature difference is less than the second condensing threshold value continues for a predetermined time or more. Effect of the Invention

[0010] According to the present technology, it is possible to realize a refrigerated storage facility that can more reliably detect abnormalities in the compressor. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view of a refrigerator according to a first embodiment; [Diagram 2] Upper cross-sectional view taken along line II-II in Figure 1. [Diagram 3] Top cross-sectional view taken along line III-III in Figure 1 [Figure 4] Block diagram showing electrical configuration [Diagram 5] Flowchart of compressor abnormality notification process [Figure 6A] Timing chart showing refrigerator operation 1 [Figure 6B] Timing chart showing refrigerator operation 2 [Figure 6C] Timing chart showing abnormality notification processing DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <Embodiment 1> A six-door refrigerator 10 (an example of a cooling storage unit) according to embodiment 1 will be described with reference to Fig. 1 to Fig. 6C. Symbols F, B, L, R, U, and D shown in some of the drawings respectively indicate the front and rear in the front-rear direction of the refrigerator 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).

[0013] As shown in Fig. 1 to Fig. 4, the refrigerator 10 includes a storage body 11, a door 12, a machine room 13, circulation fans (internal fans) 41, 42, cooling devices 20, 30, and a control unit 50. The storage body 11 is an insulated box body that opens to the front, and is configured by foaming and filling the space between an outer box 11A and an inner box 11B with insulating material. Most of the interior of the storage body 11 is one large storage chamber 14. Hereinafter, the interior of the storage body 11 may be simply referred to as the interior.

[0014] The six doors 12 are attached by hinge members so as to be able to open and close the front opening of the storage body 11. Of the six doors 12, the four on the left side are provided as two pairs of doors, one above the other, in a double door style, and the two on the right side are provided as one pair of doors, one above the other, in a right-opening style.

[0015] The cooling devices 20 and 30 are devices that cool the interior of the refrigerator (more specifically, the storage compartment 14). Since the refrigerator 10 is large and the capacity of the storage compartment 14 is large, two cooling devices 20 and 30 are provided to improve the uniformity of the temperature distribution and the cooling speed. The basic configurations of the cooling devices 20 and 30 are the same, and one provided on the left side is referred to as the first cooling device 20, and the other provided on the right side is referred to as the second cooling device 30.

[0016] The first cooling device 20 includes a first compressor 22, a first condenser fan 24, a first condenser 26, and a first cooler 28. The second cooling device 30 includes a second compressor 32, a second condenser fan 34, a second condenser 36, and a second cooler 38. The compressors 22, 32, the condensers 26, 36, and the coolers 28, 38 are connected by piping, and a known refrigeration cycle is formed by circulating a refrigerant. Note that an expansion valve or a capillary tube is interposed between the condensers 26, 36 and the coolers 28, 38.

[0017] As shown in Fig. 2 and Fig. 3, the internal fans 41, 42 circulate the air in the storage chamber 14 by sucking air from the storage chamber 14, passing it through the insides of the coolers (evaporators) 28, 38 of the cooling devices 20, 30, and returning the air cooled by the coolers 28, 38 to the storage chamber 14. One of the internal fans 41 is provided near the first cooler 28 and circulates air to pass through the first cooler 28, and the other is provided near the second cooler 38 and circulates air to pass through the second cooler 38. In this embodiment, two first internal fans 41 and one second internal fan 42 are provided, but the number and size can be appropriately changed depending on the specifications.

[0018] Two cooler chambers 15, 16 are provided in the upper part of the storage body 11. Each cooler chamber 15, 16 houses each cooler 28, 38 and each internal fan 41, 42. The storage chamber 14 and the cooler chamber 15, 16 are partitioned by cooling ducts 17, 18. The cooling ducts 17, 18 have an inclined portion that inclines downward toward the rear. The inclined portion is provided with suction ports 17A, 18A and air outlets 17B, 18B. In the cooler chambers 15, 16, above the suction ports 17A, 18A, the internal fans 41, 42 are provided. Furthermore, an internal temperature sensor 19 (specifically, a thermistor) is provided above the first internal fan 41. The internal temperature sensor 19 may be provided at any other position as long as it can detect the temperature of the air inside the storage chamber 14.

[0019] Coolers 28, 38 are arranged behind the internal fans 41, 42, as shown in an example of first cooler 28 in Fig. 3. The inclined portions of the cooling ducts 17, 18 are adapted to receive defrost water generated when frost adhering to the coolers 28, 38 melts. A drain pipe 45 is connected to the rear ends of the cooling ducts 17, 18, and the defrost water is discharged to the outside of the storage body 11 through the drain pipe 45.

[0020] As shown in Figs. 1 to 3, the machine room 13 is provided above the storage body 11. The machine room 13 houses the machinery constituting the cooling devices 20, 30 (compressors 22, 32, condenser fans 24, 34, and condensers 26, 36), an electrical equipment box 51, an operation box 52, etc. In a part of the front of the machine room 13, an operation panel (display unit 54 and operation unit 56) provided on the front of the operation box 52 is provided so as to be accessible from the outside (see Fig. 1). The display unit 54 is, for example, a 7-segment display, and displays various information. The operation unit 56 is, for example, a push-button switch, and is configured to be able to instruct the control unit 50 on operating conditions and operations.

[0021] Next, the cooling devices 20 and 30 will be described in detail. The compressors 22 and 32 use the electric motors 22A and 32A as power sources to draw in and compress the refrigerant gas, and discharge the high-temperature, high-pressure refrigerant gas. The compressors 22 and 32 according to the present embodiment are inverter compressors equipped with variable-speed electric motors 22A and 32A (e.g., AC induction motors or DC brushless motors), but may be of other types. The rotation speeds V22 and V32 of the electric motors 22A and 32A are variable in, for example, seven stages (specifically, 30 rps (rounds per second), 35 rps, 40 rps, 47 rps, 55 rps, 65 rps, and 76 rps). When the rotation speeds V22 and V32 of the electric motors 22A and 32A increase, the amount of refrigerant gas drawn in and discharged by the compressors 22 and 32 increases, and the amount of refrigerant circulating in the refrigeration cycle increases, so that the cooling capacity of the cooling devices 20 and 30 can be improved. On the other hand, the smaller the rotation speeds V22, V32 of the electric motors 22A, 32A are, the smaller the power consumption of the electric motors 22A, 32A, etc. is, thereby enabling energy saving.

[0022] The condensers 26, 36 cool and liquefy the refrigerant gas compressed by the compressors 22, 32 by air blown by the condenser fans 24, 34. As shown in Fig. 3 as an example of the first condenser 26, the condensers 26, 36 include a condenser tube 26A, a number of fins, and a condenser box 26B that houses them. The condenser tube 26A extends in the left-right direction and is folded back multiple times. The condenser tube 26A passes through the fins in the condenser box 26B, passes through the side of the condenser box 26B, and is folded back in a U-shape.

[0023] The condenser fans 24, 34 are provided behind the condensers 26, 36. When the condenser fans 24, 34 are operated, outside air passes through the condensers 26, 36 from front to back, air-cooling the condenser tube 26A. The refrigerant in the condenser tube 26A is a high-temperature gas near the inlet on the compressor 22, 32 side, and is cooled and its temperature decreases as it travels along the condenser tube 26A. When the temperature of the refrigerant gas decreases to a saturation temperature (condensation temperature) corresponding to the pressure, it begins to condense into a liquid.

[0024] Condenser temperature sensors 25, 35 (specifically, thermistors) are attached to the condensing tubes of condensers 26, 36 in a manner that the sensors are housed in a thermistor holder, as shown in an example of first condenser temperature sensor 25 in Fig. 3. Condenser temperature sensors 25, 35 according to this embodiment are attached to a central pipe including a central portion between an inlet and an outlet of the condensing tube. At least a portion of the refrigerant in the condensing tube in the central pipe is condensed and liquefied, and its temperature coincides with the condensation temperature.

[0025] An air filter 26C is attached to the front opening of the condenser box of the condenser 26, 36, as shown in the example of the first condenser 26 in Fig. 3. The air filter 26C prevents foreign matter such as dust from entering the condenser box 26B and adhering to the fins, etc. When the air filter becomes clogged, the condenser 26, 36 becomes difficult to cool with air, and the temperature increases. Therefore, the condenser temperature sensor 25, 35 can also detect abnormal clogging of the air filter.

[0026] The coolers 28, 38 reduce the pressure of the refrigerant liquid from the condensers 26, 36 using an expansion valve (capillary tube) and then vaporize it, thereby cooling the air passing through the coolers 28, 38 by the heat of vaporization. The refrigerant gas from the coolers 28, 38 is returned to the compressors 22, 32. The air inside the storage chamber 14 is sucked into the cooler chamber 15 from the intake ports 17A, 18A by the interior fans 41, 42. The sucked air is cooled by the coolers 28, 38 and blown out into the storage chamber 14 from the outlet ports 17B, 18B. This cools the stored items contained in the storage chamber 14. In addition, the air sucked in by the first interior fan 41 hits the interior temperature sensor 19, so that the temperature inside the storage chamber 14 (interior temperature) is detected.

[0027] The coolers 28, 38 include a cooling pipe, a number of fins, and a cooler box that houses them. The cooling pipe extends in the left-right direction and is folded back multiple times. Each cooler 28, 38 is provided with a cooler temperature sensor 27, 37 (specifically a thermistor) that detects the temperature of the cooler, and a defrosting heater 29, 39 that melts frost adhering to the cooler 28, 38.

[0028] The defrost heaters 29, 39 are attached to the bottom surface of the cooler box 28A, for example, as shown in an example of the defrost heater 29 in Fig. 3. The cooler temperature sensors 27, 37 are attached to the inside of one side surface (front surface) of the cooler box 28A, as shown in an example of the first cooler temperature sensor 27 in Fig. 3. The cooler temperature sensors 27, 37 are provided in the coolers 28, 38, and therefore can measure the temperatures of the coolers 28, 38 more accurately than the internal temperature sensor 19. The locations of the cooler temperature sensors 27, 37 are not particularly limited as long as they are attached to the coolers 28, 38.

[0029] The refrigerator 10 is provided with a control unit 50 that electrically controls various devices. The control unit 50 includes a main control board and a compressor control board housed in an electrical equipment box 51, and an operation board housed in an operation box 52. The main control board is configured by a microcomputer having, for example, an interface (I / F) for transmitting and receiving various information, a CPU for executing commands of a control program, a storage unit for storing various information, and a timer having a timekeeping function. The compressor control board has an inverter circuit and is connected to the electric motors 22A and 32A of the compressors 22 and 32. Note that the compressor control board according to this embodiment does not have a detection unit for directly checking the operating state of the compressors 22 and 32.

[0030] Furthermore, an external temperature sensor 55 (specifically, a thermistor) that detects the external temperature around the storage unit 11 is mounted on the operation board inside the operation box 52 (see FIG. 1). The external temperature sensor 55 may be provided in a location other than the operation board, but by mounting it on the operation board, it becomes unnecessary to lay a signal line cable connecting the external temperature sensor 55 and the operation board. Note that the temperature detected by the external temperature sensor 55 may be higher than the actual external temperature around the storage unit 11 due to heat generation by the board, etc., but there is no problem as long as this is taken into consideration when using the device.

[0031] The main control board of the control unit 50 periodically or at a necessary timing acquires the internal temperature T19, the condenser temperatures T25, T35, the cooler temperatures T27, T37, and the external temperature T55 by the internal temperature sensor 19, the condenser temperature sensors 25, 35, the cooler temperature sensors 27, 37, and the external temperature sensor 55, respectively. Based on these detected temperatures, the setting information of the memory unit, and the input information of the operation unit 56, the control unit 50 controls the compressors 22, 32, the condenser fans 24, 34, the internal fans 41, 42, and the defrosting heaters 29, 39 to perform the cooling operation and the defrosting operation. The main control board of the control unit 50 also executes the abnormality notification process of the compressors 22, 32 during the cooling operation.

[0032] When the cooling operation is started by the user's operation or the like, the control unit 50 operates the compressors 22, 32, the condenser fans 24, 34, and the interior fans 41, 42 (time t1 in FIG. 6A). The control unit 50 also compares the interior temperature T19 detected by the interior temperature sensor 19 with the set temperature. When the interior temperature T19 reaches the differential lower limit temperature Tmin, which is a predetermined temperature (e.g., 2.0 K) lower than the set temperature, the temperature is sufficiently low, so the compressors 22, 32 and the condenser fans 24, 34 are stopped (time t3 in FIG. 6A and FIG. 6B). On the other hand, when the interior temperature T19 increases due to the stopping of these and rises to the differential upper limit temperature Tmax, which is a predetermined temperature (e.g., 1.7 K) higher than the set temperature, the compressors 22, 32 and the condenser fans 24, 34 are operated (time t4 in FIG. 6A and FIG. 6B).

[0033] Here, the rotation speeds V22, V32 of the motors 22A, 32A of the compressors 22, 32 are appropriately changed within the variable speed range by the control unit 50. For example, immediately after the power is turned on or when a large amount of stored items is stored and the load inside the storage is large, the motors 22A, 32A are rotated at high speed to increase the cooling capacity of the cooling devices 20, 30.

[0034] The control unit 50 executes a defrosting operation at predetermined cooling operation times, etc. When the defrosting operation is started, the control unit 50 activates the defrosting heaters 29, 39. The control unit 50 also reads the cooler temperatures T27, T37 detected by the cooler temperature sensors 27, 37, and ends the defrosting operation when the cooler temperatures T27, T37 reach a predetermined defrosting operation end temperature. As described above, the defrosting operation according to this embodiment is performed by a heater defrosting method in which the coolers 28, 38 are heated by the defrosting heaters 29, 39 to melt frost, but may also be performed by a so-called off-cycle defrosting method.

[0035] 5, during the cooling operation, the control unit 50 executes an abnormality notification process to output information notifying an abnormality in the compressors 22, 32 (YES in step S5). The abnormality notification process includes at least a first calculation process S15, a second calculation process S20, first output processes S25 to S27, and second output processes S30 to S32.

[0036] The first calculation process S15 is a process for calculating a first cooling temperature difference D27 (=inside temperature T19-cooler temperature T27) by subtracting the cooler temperature T27 detected by the first cooler temperature sensor 27 from the inside temperature T19, and for calculating a first condensing temperature difference D25 (=condenser temperature T25-external temperature T55) by subtracting the external temperature T55 from the condenser temperature T25 detected by the first condenser temperature sensor 25. The second calculation process S20 is a process for calculating a second cooling temperature difference D37 (=inside temperature T19-cooler temperature T37) by subtracting the cooler temperature T37 detected by the second cooler temperature sensor 37 from the inside temperature T19, and for calculating a second condensing temperature difference D35 (=condenser temperature T35-external temperature T55) by subtracting the external temperature T55 from the condenser temperature T35 detected by the second condenser temperature sensor 35.

[0037] In this embodiment, since the compressors 22, 32 are inverter compressors, when the rotation speeds V22, V32 of the motors 22A, 32A are low-speed operation, the behavior of the compressors 22, 32 is close to that of a stopped state even when they are operating normally. Therefore, when an inverter compressor is used, in order to avoid erroneous detection, it is preferable that the control unit 50 executes the subsequent first output process S25 to S27 when the speed of the motor 22A is set to high speed rotation (YES in step S22), and executes the subsequent second output process S30 to S32 when the speed of the motor 32A is set to high speed rotation (YES in step S29).

[0038] Here, the high speed rotation of the electric motors 22A, 32A of the compressors 22, 32 refers to, for example, rotation speeds V22, V32 that are equal to or greater than the median and equal to or less than the upper limit in the variable speed range. Also, the low speed rotation refers to, for example, rotation speeds V22, V32 that are equal to or greater than the lower limit and less than the median in the variable speed range. In this embodiment, the variable speed range of the electric motors 22A, 32A has, for example, seven stages (30 rps, 35 rps, 40 rps, 47 rps, 55 rps, 65 rps, 76 rps), with the lower limit being 30 rps, the upper limit being 76 rps, and the median (=(lower limit + upper limit) / 2) being 53 rps. As a result, for example, high-speed rotation of electric motors 22A and 32A is defined as a state in which the speed is set to one of three speed levels (55 rps, 65 rps, 76 rps), and low-speed rotation is defined as a state in which the speed is set to one of four speed levels (30 rps, 35 rps, 40 rps, 47 rps).

[0039] The first output process S25 to S27 is a process for outputting information notifying an abnormality of the first compressor 22 (step S27) when the state in which the first cooling temperature difference D27 is less than the first cooling threshold Th27 continues for a predetermined time P27 or more (step S25) and the state in which the first condensing temperature difference D25 is less than the first condensing threshold Th25 continues for a predetermined time P25 or more (step S26). The second output process S30 to S32 is a process for outputting information notifying an abnormality of the second compressor 32 (step S32) when the state in which the second cooling temperature difference D37 is less than the second cooling threshold Th37 continues for a predetermined time P37 or more (step S30) and the state in which the second condensing temperature difference D35 is less than the second condensing threshold Th35 continues for a predetermined time P35 or more (step S31).

[0040] The first cooling threshold Th27 and the second cooling threshold Th37 may be the same or different values, and can be set appropriately, for example, in the range of +2.0 K to +5.0 K. The first condensation threshold Th25 and the second condensation threshold Th35 may be the same or different values, and can be set appropriately, for example, in the range of +1.5 K to +5.0 K. The predetermined times P27, P25, P37, and P37 may be the same or different values, and can be set appropriately, for example, in the range of 2 hours to 5 hours.

[0041] In this embodiment, in the output process of steps S27 and S32, the control unit 50 outputs information notifying an abnormality in the compressors 22, 32 to the display unit 54. As a result, an error (e.g., an alarm number) is displayed on the display unit 54. For example, the error is notified by the display unit 54 switching from a state in which only the internal temperature T19 is normally displayed to a state in which the internal temperature T19 and the internal temperature T19 are alternately displayed. However, the method of outputting the error is not limited to this, and may be, for example, a light or sound alert or an error message sent to a mobile terminal or the like.

[0042] Next, the effect of the abnormality notification process in the cooling operation will be described with reference to the timing charts of Figures 6A to 6C. First, when the cooling operation is started, the compressors 22, 32, the condenser fans 24, 34, and the internal fans 41, 42 are operated (time t1), so that the cooler temperatures T27, T37 decrease, and when they decrease to the minimum value, they settle at a constant value (time t2). The condenser temperatures T25, T35 increase, and when they increase to the maximum value, they settle at a constant value (time t2). At this time, the internal temperature T19 continues to decrease, and when it decreases to the differential lower limit temperature Tmin, the control unit 50 stops the compressors 22, 32, and the condenser fans 24, 34 (time t3). As a result, the internal temperature T19 and the cooler temperatures T27, T37 increase, and the condenser temperatures T25, T35 decrease (time t3 to t4). When the internal temperature T19 increases to the differential upper limit temperature, the control unit 50 operates the compressors 22, 32 and the condenser fans 24, 34 again (time t4). As a result, the internal temperature T19 decreases again, the cooler temperatures T27, T37 decrease again, and when they reach their minimum values, they settle down to a constant value, and the condenser temperatures T25, T35 increase again, and when they reach their maximum values, they settle down to a constant value (time t5). It is assumed that the external temperature T55 remains constant with no particular fluctuations in the surrounding environment.

[0043] Assume that the second compressor 32 stops due to an abnormality during such a cooling operation. Since the second compressor 32 stops (time t6), the cooling efficiency of the second cooling device 30 decreases, and the cooler temperature T37 increases and reaches a maximum value before settling down (time t9). Also, since the flow of high-temperature refrigerant gas flowing from the second compressor 32 into the second condenser 36 is stagnated, the condenser temperature T35 decreases and reaches a minimum value before settling down (time t9). Meanwhile, since the first compressor 22 continues to operate normally, the cooling efficiency of the first cooling device 20 remains high. As a result, the cooler temperature T27 and the condenser temperature T25 remain constant without any change (after time t6). In addition, the internal temperature T19 increases due to the stopping of the second compressor 32, but because the first compressor 22 is operating, the rate of increase is smaller than that between times t3 and t4 when both compressors 22 and 32 are stopped, and the rate gradient is slower (from time t6 onwards).

[0044] If the second compressor 32 continues to be stopped (after time t6), the cooler temperature T37 approaches the internal temperature T19 so as to be in equilibrium with the internal temperature T19. The control unit 50 calculates the second cooling temperature difference D37 and the second condensing temperature difference D35 in the second calculation process S20 described above, and monitors the changes therein (FIG. 6C). When two conditions are satisfied in the second output process S30 to S32, that is, the state (after time t7) in which the second cooling temperature difference D37 is less than the second cooling threshold (for example, +5K) continues for a predetermined time P37 or more (for example, 5 hours) (hereinafter referred to as condition 1), and the state (after time t8) in which the second condensing temperature difference D35 is less than the second condensing threshold (for example, +5K) continues for a predetermined time P35 (for example, 5 hours) or more (hereinafter referred to as condition 2), the control unit 50 outputs information notifying an abnormality (stop) of the second compressor 32 to the display unit 54 (time t10). The error (alarm number) is notified by alternating between displaying the internal temperature T19 and the internal temperature T19 in a portion of the display unit 54 that normally displays only the internal temperature T19.

[0045] This error (alarm number) display allows users and maintenance personnel to quickly learn of an abnormality in the second compressor 32. As a result, maintenance personnel can shorten the time required to identify the cause of the abnormality, and can also shorten the preparation time required for arranging replacement parts, etc. Also, by quickly learning of conditions in which the uniformity of the temperature distribution inside the refrigerator is decreasing or the cooling speed inside the refrigerator is decreasing, necessary measures can be taken quickly, and deterioration of stored items (food ingredients) can be suppressed.

[0046] Furthermore, when determining whether the second compressor 32 has stopped abnormally, by satisfying both the above-mentioned conditions 1 and 2, it is possible to detect an abnormality in the second compressor 32 more accurately and reliably than when determining based on only one of the conditions or based on the inside temperature T19. For example, when determining based only on condition 2 (step S31 in FIG. 5), in an installation environment in which cold air from an external air conditioner hits the second condenser temperature sensor, there is a concern that the second condensation temperature difference D35 will continue to be less than the second condensation threshold value Th35 even though the second compressor 32 is operating normally, and step S31 of condition 2 will be YES, resulting in a false detection. Furthermore, the refrigerator 10 according to this embodiment is provided with two cooling devices 20, 30 (two compressors 22, 32), and even if the second compressor 32 stops abnormally, the first compressor 22 operates normally. Therefore, when the second compressor 32 is detected based on the internal temperature T19, the internal temperature T19 does not reach a threshold temperature (for example, the set temperature + 10K shown in FIG. 6B) that notifies of a high temperature abnormality, or it takes a long time to reach the threshold temperature. In this regard, according to the abnormality detection process according to this embodiment, even if a plurality of cooling devices are provided, an abnormality in each compressor can be detected early.

[0047] Furthermore, in this embodiment, the compressor control board of the control unit 50 does not have a detection unit that directly checks the operating state of the compressors 22, 32, and is not provided with any control parts related to such detection. Even in such a case, abnormalities in the compressors 22, 32 can be detected more accurately and reliably at low cost.

[0048] The above provides a detailed explanation of the abnormality detection process when an abnormality (stop) occurs in the second compressor 32. However, similar processing is also performed as shown in the flowchart of Figure 5 when an abnormality occurs in the first compressor 22 and when an abnormality occurs in each of the two compressors 22, 32.

[0049] <Other embodiments> The present technology is not limited to the embodiments described above and illustrated in the drawings, and for example, the following embodiments are also included in the technical scope of the present technology.

[0050] (1) Although the abnormality detection process for the compressors 22, 32 in the refrigerator 10 having two compressors 22, 32 has been described, the present technology is also applicable to a refrigerator 10 having one or three or more cooling devices. The present technology is also applicable to an appliance having a cooling device other than a cooling storage (for example, an ice maker). [Explanation of symbols]

[0051] 10: refrigerator (cooling storage), 11: storage body, 19: internal temperature sensor, 20: first cooling device, 22: first compressor, 22A, 32A: electric motor, 25: first condenser temperature sensor, 26: first condenser, 27: first cooler temperature sensor, 28: first cooler, 30: second cooling device, 32: second compressor, 35: second condenser temperature sensor, 36: second condenser, 37: second cooler temperature sensor, 38: second cooler, 50: control unit, 55: external temperature sensor, T19: internal temperature, T25, T35: condensers Condenser temperature, T27, T37: cooler temperature, T55: external temperature, D25: first condensation temperature difference, D27: first cooling temperature difference, D35: second condensation temperature difference, D37: second cooling temperature difference, P25, P27, P35, P37: predetermined time, S15: first calculation process, S20: second calculation process, S25 to S27: first output process, S30 to S32: second output process, Th25: first condensation threshold, Th27: first cooling threshold, Th35: second condensation threshold, Th37: second cooling threshold, V22, V32: rotation speed (speed)

Claims

1. The storage body, A cooling device having a cooler into which air drawn from inside the storage body flows and cools the air passing through the inside, a compressor that compresses the refrigerant gas from the cooler, and a condenser that condenses the refrigerant gas from the compressor; An internal temperature sensor for detecting an internal temperature inside the storage body; a cooler temperature sensor for detecting a temperature of the cooler; An external temperature sensor for detecting an external temperature around the storage body; a condenser temperature sensor for detecting a temperature of the condenser; A control unit that executes an abnormality notification process that outputs information notifying an abnormality of the compressor, The abnormality notification process includes: A calculation process of calculating a cooling temperature difference by subtracting the cooler temperature detected by the cooler temperature sensor from the internal temperature, and calculating a condensation temperature difference by subtracting the external temperature from the condenser temperature detected by the condenser temperature sensor; and an output process for outputting information notifying of an abnormality in the compressor when the cooling temperature difference remains below the cooling threshold for a predetermined period of time or more and the condensation temperature difference remains below the condensation threshold for a predetermined period of time or more.

2. the compressor having a variable speed motor; The cooling storage facility according to claim 1 , wherein the control unit executes the output process when the speed of the electric motor is set to be equal to or higher than a median value and equal to or lower than an upper limit value in a variable speed range.

3. The cooling device includes a first cooling device and a second cooling device, The first cooling device includes a first cooler, a first compressor, and a first condenser, The second cooling device includes a second cooler, a second compressor, and a second condenser, the cooler temperature sensor includes a first cooler temperature sensor that detects a temperature of the first cooler and a second cooler temperature sensor that detects a temperature of the second cooler; the condenser temperature sensor includes a first condenser temperature sensor that detects a temperature of the first condenser and a second condenser temperature sensor that detects a temperature of the second condenser; The calculation process includes: a first calculation process for calculating a first cooling temperature difference by subtracting the cooler temperature detected by the first cooler temperature sensor from the internal temperature, and calculating a first condensing temperature difference by subtracting the external temperature from the condenser temperature detected by the first condenser temperature sensor; A second calculation process of calculating a second cooling temperature difference by subtracting the cooler temperature detected by the second cooler temperature sensor from the internal temperature, and calculating a second condensing temperature difference by subtracting the external temperature from the condenser temperature detected by the second condenser temperature sensor, The output process includes: a first output process that outputs information notifying an abnormality of the first compressor when a state in which the first cooling temperature difference is less than a first cooling threshold value continues for a predetermined time or more and a state in which the first condensing temperature difference is less than a first condensing threshold value continues for a predetermined time or more; The cooling storage facility described in claim 1 or claim 2, further comprising a second output process that outputs information notifying of an abnormality in the second compressor when the second cooling temperature difference remains less than a second cooling threshold for a predetermined period of time or more and the second condensing temperature difference remains less than a second condensing threshold for a predetermined period of time or more.

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