Cooling storage

Abstract

To provide a cooling storage unit that can more reliably start the compressor when the condenser temperature rises. [Solution] During cooling operation, if the temperature detected by the condenser temperature sensor 46 becomes equal to or greater than a preset third set temperature TC, the control unit 60 performs a storage process to store the first detected temperature T1, which is the temperature detected by the condenser temperature sensor 31, in the storage unit 61 before executing the process to start the compressor 22 in the next cooling operation A1; a solenoid valve opening / closing process to open the solenoid valve 52 for a predetermined time X3 (second predetermined time) and then close the solenoid valve 52, if the second detected temperature T2, which is the temperature detected by the condenser temperature sensor 31 after a predetermined time X1 (first predetermined time) has elapsed since the process to start the compressor 22, is not lower than the first detected temperature T1; and a compressor start-up process to execute the process to start the compressor 22, which is performed after the solenoid valve opening / closing process.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a cooling refrigerator.

Background Art

[0002] Conventionally, as a cooling refrigerator, one equipped with a cooling device capable of cooling a storage chamber is known. As such a cooling device, the one described in Patent Document 1 below is known. The cooling device (refrigerator) described in this Patent Document 1 includes a compressor, a cooler (evaporator), a condenser, and a condenser fan for cooling the condenser.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above configuration, when the temperature of the condenser rises due to an abnormality occurring in the condenser fan or the installation location of the cooling refrigerator becoming high, the pressure on the discharge side of the compressor increases, and the differential pressure with the suction side of the compressor increases. If the differential pressure between the discharge side and the suction side of the compressor is large, there is a concern that the compressor cannot be started. As a result, there is a problem that cooling by the cooling device cannot be performed and the temperature of the storage chamber rises.

[0005] The technology disclosed in this specification has been completed based on the above circumstances, and an object thereof is to provide a cooling refrigerator capable of more reliably starting the compressor when the temperature of the condenser rises.

Means for Solving the Problems

[0006] As a means to solve the above problems, the cooling storage facility disclosed herein includes a storage facility body having a storage chamber, a cooling device capable of cooling the storage chamber, a cooling circuit comprising a compressor, a condenser, a cooler, a refrigerant pipe circulating and connecting the compressor, the condenser, and the cooler and filled with a refrigerant, a condenser temperature sensor for detecting the temperature of the condenser, a cooler temperature sensor for detecting the temperature of the cooler, a storage chamber temperature sensor for detecting the temperature of the storage chamber, piping connecting the suction side and the discharge side of the compressor in the cooling circuit, a solenoid valve provided in the piping, a control unit, and a memory unit, wherein the control unit executes a process to start the compressor when the temperature detected by the storage chamber temperature sensor is equal to or higher than a preset first set temperature, and thereafter, when the temperature detected by the storage chamber temperature sensor becomes a second set temperature which is lower than the first set temperature, the pressure The system is configured to perform a cooling operation to stop the compressor, and furthermore, the control unit is characterized in that, during the cooling operation, if the temperature detected by the condenser temperature sensor becomes equal to or above a preset third set temperature, in the next cooling operation, before executing the process to start the compressor, it stores in the storage unit a first detected temperature, which is the temperature detected by either the condenser temperature sensor or the storage chamber temperature sensor; after the storage operation, if the second detected temperature, which is the temperature detected by the one of the temperature sensors after a first predetermined time has elapsed since the process to start the compressor, is not lower than the first detected temperature or is not lower than the first detected temperature by a predetermined value or more, it opens the solenoid valve for a second predetermined time and then closes the solenoid valve; and after the solenoid valve opening and closing process, it executes a compressor start-up process that executes the process to start the compressor.

[0007] Furthermore, the control unit may open the solenoid valve for a third predetermined time and then close it between the time it executes the memory processing and the time it executes the processing to start the compressor.

[0008] Furthermore, as a means to solve the above problems, the cooling storage facility disclosed herein includes a storage facility body having a storage chamber, a cooling device capable of cooling the storage chamber, a cooling circuit comprising a compressor, a condenser, a cooler, a refrigerant pipe that circulates and connects the compressor, the condenser, and the cooler and is filled with a refrigerant, a condenser temperature sensor for detecting the temperature of the condenser, a storage chamber temperature sensor for detecting the temperature of the storage chamber, piping connecting the suction side and the discharge side of the compressor in the cooling circuit, a solenoid valve provided in the piping, and a control unit, wherein the control unit controls the storage chamber The system is configured to perform a process to start the compressor when the temperature detected by the temperature sensor is equal to or higher than a preset first set temperature, and then to perform a cooling operation to stop the compressor when the temperature detected by the storage chamber temperature sensor becomes a second set temperature which is lower than the first set temperature. Furthermore, the control unit is characterized in that, during the cooling operation, if the temperature detected by the condenser temperature sensor becomes equal to or higher than a preset third set temperature, it opens the solenoid valve for a predetermined time and then closes the solenoid valve before performing the process to start the compressor in the next cooling operation.

[0009] Furthermore, the control unit may include a storage unit and a cooler temperature sensor for detecting the temperature of the cooler, and during the cooling operation, if the temperature detected by the condenser temperature sensor becomes equal to or greater than the third set temperature, the control unit may perform a storage process to store in the storage unit a first detected temperature, which is the temperature detected by either the cooler temperature sensor or the storage chamber temperature sensor, before executing the process for starting the compressor in the next cooling operation; a solenoid valve opening / closing process, which is performed after the storage process and is the temperature detected by the one of the temperature sensors after a first predetermined time has elapsed since the process for starting the compressor, if the second detected temperature is not lower than the first detected temperature or is not lower than the first detected temperature by a predetermined value or more, the solenoid valve opening / closing process, which opens the solenoid valve for a second predetermined time and then closes the solenoid valve; and a compressor starting process, which is performed after the solenoid valve opening / closing process and is the process for starting the compressor. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a cooling storage unit that can more reliably start the compressor when the temperature of the condenser rises. [Brief explanation of the drawing]

[0011] [Figure 1] A perspective view showing a cooling storage unit according to Embodiment 1 of the present invention. [Figure 2] Cross-sectional view showing the upper part of the storage unit and the cooling system. [Figure 3] Diagram showing the cooling circuit [Figure 4] Block diagram showing the electrical configuration of the cooling storage unit. [Figure 5] Flowchart showing the processing of the control unit during cooling operation A1 [Figure 6] Flowchart showing the processing of the control unit in cooling operation A1 according to Embodiment 2 [Modes for carrying out the invention]

[0012] <Embodiment 1> Embodiment 1 of the present invention will be described with reference to Figures 1 to 5. In this embodiment, a prefabricated cooling storage unit 10 is exemplified as a cooling storage unit. As shown in Figure 1, the cooling storage unit 10 comprises a box-shaped storage unit body 12 having a storage chamber 11. The storage unit body 12 is constructed by assembling a plurality of insulating panels. The insulating panels constituting the storage unit body 12 are constructed by foaming and filling the inside of the outer shell with insulating material. An opening 13 is formed in the front wall portion of the storage unit body 12, which serves as an entrance to the storage chamber 11. An insulating door 14 is attached to the storage unit body 12 to open and close the opening 13.

[0013] The refrigerated storage unit 10 is equipped with a cooling device 20 capable of cooling the storage room 11. The cooling device 20 is installed on the upper surface of the ceiling wall 12A of the storage unit body 12. As shown in Figures 1 and 2, the cooling device 20 comprises a plate-shaped base 21, a compressor 22, a condenser 23, a cooler 24, an electrical box 25, a cooling fan 26, a condenser fan 27, and a case 28. The cooling device 20 (cooling unit) is unitized by arranging each component (compressor 22, condenser 23, cooler 24, electrical box 25, cooling fan 26, condenser fan 27, case 28) on the base 21.

[0014] Case 28 has thermal insulation properties and, as shown in Figure 2, is box-shaped with an opening at the bottom. The internal space 28A of case 28 houses the cooler 24 and the cooling fan 26. The internal space 28A is in communication with the storage room 11 via an intake port 29 and an outlet port 30 formed by penetrating the ceiling wall 12A and the base 21.

[0015] When the cooling fan 26 is activated, air from inside the storage chamber 11 is drawn in through the intake port 29 into the internal space 28A (cooler chamber) (the airflow is shown by arrow F1), cooled by heat exchange as it passes through the cooler 24, and then blown back into the storage chamber 11 from the outlet port 30 (the airflow is shown by arrow F2). This circulation of air cools the inside of the storage chamber 11.

[0016] Furthermore, the case 28 contains a cooler temperature sensor 31 for detecting the temperature of the cooler 24 and a storage chamber temperature sensor 32 for detecting the temperature of the storage chamber 11. The cooler temperature sensor 31 is provided in contact with the cooler 24. The storage chamber temperature sensor 32 is attached to the cooler 24, for example, via a bracket (not shown). The storage chamber temperature sensor 32 is capable of detecting the temperature of the air (temperature of the storage chamber 11) drawn into the internal space 28A from the intake port 29.

[0017] Next, the cooling circuit 40 included in the cooling device 20 will be described. As shown in FIG. 3, the cooling circuit 40 includes a compressor 22 that compresses a refrigerant, a condenser 23 that cools and liquefies the compressed refrigerant gas by the blowing of a condenser fan 27, a dryer 41, an expansion valve 42 that expands the liquefied refrigerant, a cooler 24 that vaporizes the expanded liquefied refrigerant, a heat exchanger 43, and a refrigerant pipe 45 filled with the refrigerant. The refrigerant pipe 45 is configured to circulate and connect the compressor 22, the condenser 23, the dryer 41, the expansion valve 42, and the cooler 24.

[0018] The dryer 41 has a function of removing moisture mixed in the refrigerant pipe 45. The expansion valve 42 is, for example, a temperature-type automatic expansion valve and is connected to a temperature-sensing cylinder 47 provided at a portion of the refrigerant pipe 45 that constitutes the vicinity of the outlet of the cooler 24. The heat exchanger 43 is configured to be able to exchange heat between the refrigerant flowing between the dryer 41 and the expansion valve 42 and the refrigerant flowing between the cooler 24 and the compressor 22. Thereby, the refrigerant on the upstream side of the expansion valve 42 can be cooled, and the cooling capacity can be improved. Further, a condenser temperature sensor 46 for detecting the temperature of the condenser 23 is provided at a portion of the refrigerant pipe 45 that constitutes the vicinity of the outlet of the condenser 23.

[0019] Further, the cooling storage 10 includes a pipe 51. As shown in FIG. 3, the pipe 51 (bypass pipe) connects a refrigerant pipe component 45A that is a portion of the refrigerant pipe 45 connecting the compressor 22 and the condenser 23 and a refrigerant pipe component 45B that is a portion of the refrigerant pipe 45 connecting the expansion valve 42 and the cooler 24. That is, the pipe 51 is configured to connect the suction side (low-pressure side, refrigerant pipe component 45B) of the compressor 22 and the discharge side (high-pressure side, refrigerant pipe component 45A) of the compressor 22 in the cooling circuit 40. An electromagnetic valve 52 is provided in the pipe 51. By opening the electromagnetic valve 52, the internal space of the refrigerant pipe component 45A and the internal space of the refrigerant pipe component 45B are configured to communicate with each other through the pipe 5.

[0020] Also, with the compressor 22 operating, by opening the solenoid valve 52, the high-temperature gas refrigerant (hot gas) compressed by the compressor 22 is supplied to the cooler 24. Thereby, it becomes possible to heat and defrost the cooler 24. That is, the solenoid valve 52 functions as a hot gas valve.

[0021] Next, the electrical configuration of the refrigerating storage 10 will be described. As shown in FIG. 4, the refrigerating storage 10 includes a control unit 60. The control unit 60 is electrically connected to a storage unit 61, a timing unit 62, a compressor 22, a cooling fan 26, a condenser fan 27, a cooler temperature sensor 31, a storage chamber temperature sensor 32, a condenser temperature sensor 46, and a solenoid valve 52, respectively. The control unit 60 is mainly composed of, for example, a CPU, and the storage unit 61 is composed of, for example, a ROM, a RAM, etc.

[0022] By executing the computer program stored in the storage unit 61, the control unit 60 can control the operation of each device (compressor 22, cooling fan 26, condenser fan 27, solenoid valve 52, etc.) connected to the control unit 60. Also, various setting values regarding the operation of the refrigerating storage 10 are stored in the storage unit 61. The timing unit 62 is configured to measure time.

[0023] Next, the processing of the control unit 60 will be described. Based on the temperature detected by the storage room temperature sensor 32, the control unit 60 controls the cooling device 20 (compressor 22, cooling fan 26, condenser fan 27) to perform a cooling operation to cool the inside of the storage room 11. Specifically, during the cooling operation, the control unit 60 starts the compressor 22 and condenser fan 27 when the temperature detected by the storage room temperature sensor 32 is equal to or higher than a preset first set temperature TA, and then stops the compressor 22 and condenser fan 27 when the temperature detected by the storage room temperature sensor 32 becomes a second set temperature TB, which is set to a temperature lower than the first set temperature TA. In addition, the control unit 60 keeps the cooling fan 26 running at all times when power is supplied to the cooling storage unit 10. The control unit 60 may also operate the cooling fan 26 in synchronization with the operation of the compressor 22. Furthermore, the control unit 60 may operate the cooling fan 26 intermittently when the compressor 22 is not operating, and operate the cooling fan 26 continuously when the compressor 22 is operating.

[0024] The first set temperature TA (upper limit set temperature) is the preset target set temperature TM + predetermined temperature TD (e.g., 2K), and the second set temperature TB (lower limit set temperature) is the target set temperature TM - predetermined temperature TE (e.g., 2K). By repeating this cooling operation, the temperature inside the storage chamber 11 is maintained near the target set temperature TM (between the first set temperature TA and the second set temperature TB). Here, "the control unit 60 starts the compressor 22" means "the control unit 60 executes a process to start the compressor 22," specifically, the control unit 60 sends an electrical signal (compressor operation signal) to the compressor 22 to start it. The same applies to the condenser fan 27.

[0025] When the temperature of the condenser 23 rises during cooling operation, the pressure on the discharge side of the compressor 22 in the cooling circuit 40 increases, and the pressure difference between the discharge side and the suction side of the compressor 22 becomes large. If the pressure difference between the discharge side and the suction side of the compressor 22 is large, there is a concern that the compressor 22 may not be able to start during the next cooling operation. Therefore, when the temperature detected by the condenser temperature sensor 46 during cooling operation becomes equal to or higher than the preset third set temperature TC, the control unit 60 performs memory processing, solenoid valve opening / closing processing executed after the memory processing, and compressor start processing executed after the solenoid valve opening / closing processing during the next cooling operation (referred to as cooling operation A1 in the following description), thereby ensuring that the compressor 22 starts more reliably.

[0026] Furthermore, if the temperature detected by the condenser temperature sensor 46 during the cooling operation reaches or exceeds the third set temperature TC, the control unit 60 will stop the cooling operation. However, if the third set temperature TC is set to a relatively low temperature (for example, a temperature lower than the temperature at which the compressor 22 must be stopped), the cooling operation may be continued even if the temperature detected by the condenser temperature sensor 46 reaches or exceeds the third set temperature TC during the cooling operation.

[0027] Next, the processing of the control unit 60 during cooling operation A1 will be described. During cooling operation A1, as shown in Figure 5, the control unit 60 stores the first detected temperature T1, which is the temperature detected by the cooler temperature sensor 31 (either the cooler temperature sensor or the storage room temperature sensor), in the storage unit 61 before executing the process for starting the compressor 22 (step S14) (storage processing, step S11).

[0028] Next, as shown in Figure 5, the control unit 60 opens the solenoid valve 52 for a predetermined time X3 (for example, 10 seconds, third predetermined time) and then closes the solenoid valve 52 (steps S12, S13). Next, the control unit 60 starts the compressor 22 and the condenser fan 27 (step S14). In other words, between executing the memory processing (step S11) and executing the processing to start the compressor 22 (step S14), the control unit 60 opens the solenoid valve 52 for a predetermined time X3 and then closes the solenoid valve 52. To put it another way, if the temperature detected by the condenser temperature sensor 46 during the cooling operation becomes equal to or above the preset third set temperature TC, the control unit 60 opens the solenoid valve 52 for a predetermined time X3 and then closes the solenoid valve before executing the processing to start the compressor 22 in the next cooling operation A1.

[0029] Next, the control unit 60 stores the second detected temperature T2, which is the temperature detected by the cooler temperature sensor 31, in the storage unit 61 after a predetermined time X1 (first predetermined time) has elapsed (YES in step S15) (step S16). In other words, the second detected temperature T2 is the temperature detected by the cooler temperature sensor 31 (either the cooler temperature sensor or the storage room temperature sensor) after a predetermined time X1 has elapsed since the process for starting the compressor 22 (step S14) was executed.

[0030] If the compressor 22 fails to start despite the execution of the process to start the compressor 22 (step S14), the cooling device 20 will not function and the temperature of the cooler 24 will not decrease. Therefore, the control unit 60 compares the second detected temperature T2 with the first detected temperature T1 to determine whether the compressor 22 has started or not. If the second detected temperature T2 is not lower than the first detected temperature T1 (NO in step S17), the control unit 60 determines that the compressor 22 has not started and stops the compressor 22 and the condenser fan 27 (step S18). Then, it opens the solenoid valve 52 for a predetermined time X3 (second predetermined time) and then closes the solenoid valve 52 (solenoid valve opening / closing process, steps S12, S13). After closing the solenoid valve 52, the control unit 60 executes the process to start the compressor 22 (compressor start process, step S14).

[0031] In step S18, "the control unit 60 stops the compressor 22" means "the control unit 60 executes a process to stop the compressor 22," specifically, the control unit 60 sends an electrical signal to the compressor 22 to stop it. Executing step S18 suggests that the compressor 22 has not started, but this process is performed because it is necessary to ensure the compressor 22 is stopped before opening the solenoid valve 52.

[0032] Furthermore, as shown in Figure 5, if the second detected temperature T2 is lower than the first detected temperature T1 (YES in step S17), the control unit 60 updates and stores the first detected temperature T1 (step S20), and after a predetermined time X1 has elapsed, compares it with the updated second detected temperature T2 (step S17). The processes in steps S20, S15, S16, and S17 are repeatedly executed until the temperature detected by the storage chamber temperature sensor 32 falls below the second set temperature TB (YES in step S19, in other words, until the cooling operation A1 is completed). Alternatively, if the second detected temperature T2 is lower than the first detected temperature T1, the control unit 60 may not execute the process in step S20 and may wait until the temperature detected by the storage chamber temperature sensor 32 falls below the second set temperature TB.

[0033] Next, the effects of this embodiment will be described. The cooling storage unit 10 of this embodiment includes a storage unit body 12 having a storage chamber 11, a cooling circuit 40 comprising a compressor 22, a condenser 23, a cooler 24, a refrigerant pipe 45 that circulates the compressor 22, the condenser 23, and the cooler 24 and is filled with refrigerant, a cooling device 20 capable of cooling the storage chamber 11, a condenser temperature sensor 46 for detecting the temperature of the condenser 23, a cooler temperature sensor 31 for detecting the temperature of the cooler 24, a storage chamber temperature sensor 32 for detecting the temperature of the storage chamber 11, a pipe 51 connecting the suction side and the discharge side of the compressor 22 in the cooling circuit 40, a solenoid valve 52 provided in the pipe 51, a control unit 60, and a memory unit 61. The control unit 60 executes a process to start the compressor 22 when the temperature detected by the storage chamber temperature sensor 32 is above a preset first set temperature TA, and thereafter, when the temperature detected by the storage chamber temperature sensor 32 is above the first set temperature TA The system is configured to perform a cooling operation in which the compressor 22 is stopped when the temperature reaches a second set temperature TB which is set to a lower temperature. Furthermore, during the cooling operation, if the temperature detected by the condenser temperature sensor 46 becomes equal to or greater than a preset third set temperature TC, the control unit 60 performs a storage process in which it stores the first detected temperature T1, which is the temperature detected by the condenser temperature sensor 31, in the storage unit 61 before executing the process to start the compressor 22 in the next cooling operation A1. After the storage process, if the second detected temperature T2, which is the temperature detected by the condenser temperature sensor 31 after a predetermined time X1 (first predetermined time) has elapsed since the process to start the compressor 22 was executed, is not lower than the first detected temperature T1, it performs a solenoid valve opening / closing process in which it opens the solenoid valve 52 for a predetermined time X3 (second predetermined time) and then closes the solenoid valve 52. After the solenoid valve opening / closing process, it performs a compressor start-up process in which it executes the process to start the compressor 22.

[0034] If the temperature of the condenser 23 rises during the cooling operation, the pressure on the discharge side of the compressor 22 in the cooling circuit 40 increases, and the pressure difference between the discharge side and the suction side of the compressor 22 increases. If the pressure difference between the discharge side and the suction side of the compressor 22 is large, there is a concern that the starting torque of the compressor 22 motor required to start the compressor 22 will be insufficient, and the compressor 22 may not be able to start during the next cooling operation. For this reason, if the temperature detected by the condenser temperature sensor 46 becomes TC or higher during the cooling operation, the control unit 60 performs memory processing, solenoid valve opening / closing processing, and compressor starting processing in the next cooling operation A1.

[0035] If the compressor 22 fails to start, the temperature of the cooler 24 will not decrease. Therefore, if the second detected temperature T2 (the temperature detected by the cooler temperature sensor 31 after a predetermined time X1 has elapsed since the process to start the compressor 22 was executed) is not lower than the first detected temperature T1 (the temperature detected by the cooler temperature sensor 31 before the process to start the compressor 22 was executed), the control unit 60 determines that the compressor 22 has not started despite having executed the process to start the compressor 22 (step S14 in Figure 5), and opens the solenoid valve 52. As a result, the suction side and the discharge side of the compressor 22 are connected by the piping 51, and the pressure is equalized (solenoid valve opening / closing process, steps S12, S13).

[0036] Subsequently, in the compressor startup process (step S14), the control unit 60 executes a process to start the compressor 22. As described above, in this embodiment, when the temperature of the condenser 23 rises, the compressor 22 can be started more reliably by equalizing the pressure on the suction side and discharge side of the compressor 22 and then executing a process to start the compressor 22.

[0037] Furthermore, between executing the memory processing (step S11) and executing the processing to start the compressor 22, the control unit 60 opens the solenoid valve 52 for a predetermined time X3 (third predetermined time) and then closes the solenoid valve 52.

[0038] Opening the solenoid valve 52 equalizes the pressure on the suction and discharge sides of the compressor 22. This allows for more reliable startup of the compressor 22 the first time the process to start the compressor 22 is performed after the memory processing has been executed. Note that opening the solenoid valve 52 may cause the refrigerant in the refrigerant pipe 45 to move through the piping 51, potentially changing the temperature of the cooler 24. In the above configuration, since the memory processing is performed before opening the solenoid valve 52, a more accurate temperature of the cooler 24 can be stored as the first detected temperature T1.

[0039] Furthermore, in this embodiment, the solenoid valve opening / closing process and the compressor starting process are repeatedly executed until the second detected temperature T2 becomes lower than the first detected temperature T1 (in other words, until the compressor 22 can be started). Therefore, even if the suction and discharge sides of the compressor 22 are not sufficiently equalized by a single solenoid valve opening / closing process and the compressor starting process are not executed, the compressor 22 can be started more reliably by repeatedly executing the solenoid valve opening / closing process and the compressor starting process. If the compressor 22 cannot be started even after repeating the solenoid valve opening / closing process and the compressor starting process a predetermined number of times, the control unit 60 displays an error on a display unit (not shown) and executes a process to stop the compressor 22 and the condenser fan 27.

[0040] Furthermore, in this embodiment, since the compressor 22 is started or not is determined by using the temperature detected by the cooler temperature sensor 31 (second detected temperature T2 and first detected temperature T1), there is no need to provide a dedicated sensor for detecting the start of the compressor 22, which is preferable.

[0041] Furthermore, if the temperature detected by the condenser temperature sensor 46 during cooling operation reaches or exceeds a preset third set temperature TC, the control unit 60 opens the solenoid valve 52 for a predetermined time X3 and then closes it in the next cooling operation A1 before executing the process to start the compressor 22. By opening the solenoid valve 52, the suction and discharge sides of the compressor 22 are made pressure equal. This makes it possible to more reliably start the compressor 22 when the process to start the compressor 22 is executed. For this reason, in this embodiment, the compressor 22 can be started more reliably when the temperature of the condenser 23 rises.

[0042] <Embodiment 2> Embodiment 2 will be described with reference to Figure 6. The same reference numerals are used for parts identical to those in the above embodiment, and redundant explanations are omitted. In this embodiment, the processing of the control unit 60 in cooling operation A1 (the cooling operation following the cooling operation in which the temperature detected by the condenser temperature sensor 46 is equal to or greater than the preset third set temperature TC) differs from that of the above embodiment. In this embodiment, in cooling operation A1, the control unit 60 executes the process of step S217 instead of the process of step S17 in Figure 5, as shown in Figure 6.

[0043] Specifically, as shown in Figure 6, the control unit 60 determines that the compressor 22 has not started if the second detected temperature T2 is not at least a predetermined value Y1 (a predetermined temperature, for example, 1°C) lower than the first detected temperature T1 (resulting in "NO" in step S217), and stops the compressor 22 and the condenser fan 27 (step S18). Then, it opens the solenoid valve 52 for a predetermined time X3 (second predetermined time) and then closes the solenoid valve 52 (solenoid valve opening / closing process, steps S12, S13). After closing the solenoid valve 52, the control unit 60 executes a process to start the compressor 22 (compressor start process, step S14).

[0044] If the second detected temperature T2 is not at least a predetermined value Y1 lower than the first detected temperature T1, it can be considered that the compressor 22 has not started and the temperature of the cooler 24 has not dropped sufficiently (not by at least a predetermined value Y1). Therefore, the control unit 60 determines that the compressor 22 has not started and opens the solenoid valve 52. This connects the suction side and the discharge side of the compressor 22 via the piping 51, equalizing the pressure. Subsequently, the process to start the compressor 22 is executed, allowing the compressor 22 to start more reliably. Note that the predetermined value Y1 is not limited to the value described above and can be changed as appropriate.

[0045] <Other Embodiments> The technologies disclosed herein are not limited to the embodiments described above in the description and drawings, but also include, for example, the following embodiments. (1) In the above embodiment, the first detection temperature T1 and the second detection temperature T2 were the temperatures detected by the cooler temperature sensor 31. However, when the compressor 22 is running and the cooling fan 26 is operating, the temperature of the storage chamber 11 also decreases in the same way as the cooler 24. For this reason, the temperature detected by the storage chamber temperature sensor 32 may be used to determine whether or not the compressor 22 is running. In other words, the first detection temperature T1 and the second detection temperature T2 may be the temperatures detected by the storage chamber temperature sensor 32. However, it is preferable to use the temperature of the cooler 24 to determine whether or not the compressor 22 is running, as this allows for a more reliable determination. Note that when the solenoid valve 52 is opened, the refrigerant in the refrigerant pipe 45 moves through the piping 51, which changes the temperature of the cooler 24 and may result in a change in the temperature of the storage chamber 11. In the above embodiment, since the memory processing is performed before opening the solenoid valve 52, when the first detected temperature T1 is set to the temperature detected by the storage chamber temperature sensor 32, a more accurate temperature of the storage chamber 11 can be stored as the first detected temperature T1. Note that the amount of temperature change of the cooler 24 due to refrigerant movement when the solenoid valve 52 is opened is small, and the effect of such a temperature change of the cooler 24 on the temperature of the storage chamber 11 is small. For this reason, performing the memory processing before opening the solenoid valve 52 is more effective when the first detected temperature T1 is set to the temperature detected by the cooler temperature sensor 31. (2) The locations of the piping and solenoid valves are not limited to those exemplified in the above embodiment and can be changed as appropriate. For example, as shown by the dashed line in Figure 3, in the cooling circuit 40, the portion between the compressor 22 and the cooler 24 and the portion between the compressor 22 and the condenser 23 may be connected by piping (see reference numeral 151), and the suction side and discharge side of the compressor 22 may be equalized by opening and closing a solenoid valve provided in the piping 151. (3) In the above embodiment, a prefabricated cooling storage facility was given as an example of a cooling storage facility, but it is not limited to a prefabricated facility. [Explanation of Symbols]

[0046] 10...Cooling storage unit, 11...Storage room, 12...Storage unit body, 20...Cooling device, 22...Compressor, 23...Condenser, 24...Cooler, 31...Cooler temperature sensor, 32...Storage room temperature sensor, 40...Cooling circuit, 45...Refrigerant pipe, 46...Condenser temperature sensor, 51...Piping, 52...Solenoid valve, 60...Control unit, 61...Memory unit, T1...First detected temperature, T2...Second detected temperature, TA...First set temperature, TB...Second set temperature, TC...Third set temperature, X1...Determined time (First predetermined time), X3...Determined time (Second predetermined time, Third predetermined time)

Claims

1. A storage facility with a storage room, A cooling device capable of cooling the storage chamber includes a cooling circuit comprising a compressor, a condenser, a cooler, and a refrigerant pipe containing a refrigerant that circulates and connects the compressor, the condenser, and the cooler, A condenser temperature sensor for detecting the temperature of the condenser, A cooler temperature sensor for detecting the temperature of the cooler, A storage room temperature sensor for detecting the temperature of the storage room, A piping connecting the suction side and the discharge side of the compressor in the cooling circuit, A solenoid valve is provided in the aforementioned piping, Control unit and It includes a memory unit, The control unit performs a process to start the compressor when the temperature detected by the storage chamber temperature sensor is equal to or higher than a preset first set temperature, and then performs a cooling operation to stop the compressor when the temperature detected by the storage chamber temperature sensor falls to a second set temperature which is lower than the first set temperature. Furthermore, if the temperature detected by the condenser temperature sensor during the cooling operation reaches or exceeds a preset third set temperature, the control unit will, in the next cooling operation, Before executing the process for starting the compressor, a storage process is performed to store in the storage unit a first detected temperature, which is the temperature detected by either the cooler temperature sensor or the storage chamber temperature sensor. If the second detected temperature, which is the temperature detected by one of the temperature sensors after the first predetermined time has elapsed since the memory processing described above was performed, is not lower than the first detected temperature or is not lower than a predetermined value compared to the first detected temperature, then the solenoid valve is opened for a second predetermined time and then closed, and solenoid valve opening / closing processing is performed, A cooling storage facility that performs a compressor startup process, which is executed after the solenoid valve opening and closing process, and which is performed to start the compressor.

2. The cooling storage unit according to claim 1, wherein the control unit opens the solenoid valve for a third predetermined time and then closes the solenoid valve between the time it has performed the memory processing and the time it has performed the processing to start the compressor.

3. A storage facility with a storage room, A cooling device capable of cooling the storage chamber includes a cooling circuit comprising a compressor, a condenser, a cooler, and a refrigerant pipe containing a refrigerant that circulates and connects the compressor, the condenser, and the cooler, A condenser temperature sensor for detecting the temperature of the condenser, A storage room temperature sensor for detecting the temperature of the storage room, A piping connecting the suction side and the discharge side of the compressor in the cooling circuit, A solenoid valve is provided in the aforementioned piping, It comprises a control unit and, The control unit performs a process to start the compressor when the temperature detected by the storage chamber temperature sensor is equal to or higher than a preset first set temperature, and then performs a cooling operation to stop the compressor when the temperature detected by the storage chamber temperature sensor falls to a second set temperature which is lower than the first set temperature. Furthermore, the control unit, when the temperature detected by the condenser temperature sensor during the cooling operation becomes equal to or above a preset third set temperature, opens the solenoid valve for a predetermined time and then closes the solenoid valve before executing the process to start the compressor in the next cooling operation, in a cooling storage unit.

4. Memory unit and, The system includes a cooler temperature sensor for detecting the temperature of the cooler, If the temperature detected by the condenser temperature sensor during the cooling operation becomes equal to or greater than the third set temperature, the control unit will, in the next cooling operation, Before executing the process for starting the compressor, a storage process is performed to store in the storage unit a first detected temperature, which is the temperature detected by either the cooler temperature sensor or the storage chamber temperature sensor. If the second detected temperature, which is the temperature detected by one of the temperature sensors after the first predetermined time has elapsed since the memory processing described above was performed, is not lower than the first detected temperature or is not lower than a predetermined value compared to the first detected temperature, then the solenoid valve is opened for a second predetermined time and then closed, and solenoid valve opening / closing processing is performed, A cooling storage unit according to claim 3, which performs a compressor startup process that is executed after the solenoid valve opening and closing process and performs a process for starting the compressor.

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