Cooling device

Abstract

To reduce the amount of frost buildup on the evaporator and suppress the decrease in cooling capacity. [Solution] A cooling device that cools the internal air of a cold storage unit 5 constituting a cold storage unit by circulating refrigerant through a refrigerant line 15, comprising a refrigerant circuit 10 configured by sequentially connecting an evaporator 14 installed in the cold storage unit, a compressor 11 that sucks in and compresses the refrigerant evaporated in the evaporator 14, a condenser 12 that condenses the refrigerant compressed by the compressor 11, and an expansion mechanism 13 that adiabatically expands the refrigerant condensed in the condenser 12, the cooling device comprising a refrigerant inlet temperature detection unit 23 that detects the refrigerant inlet temperature, which is the refrigerant temperature at the inlet of the evaporator 14, and a control unit 30 that drives the compressor 11 so that the refrigerant inlet temperature detected by the refrigerant inlet temperature detection unit 23 approaches a target evaporation temperature near 0°C, provided that the conditions for opening the front opening 2a formed in the cold storage unit and facing the cold storage unit 5 are met.

Description

Technical Field

[0005]

[0001] The present invention relates to a cooling device.

Background Art

[0002] For example, in cold storage facilities such as showcases and article storage devices that store goods in a cooled state, a refrigerant circuit is provided in which an evaporator, a compressor, a condenser, and an expansion mechanism are sequentially connected by a refrigerant pipe, and the refrigerant is circulated in this refrigerant circuit to cool the internal air of the cold storage that stores the goods and thereby cool the goods. In such cold storage facilities, there is a front opening facing the cold storage, and there is one in which the front opening is opened and closed by a door body (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above-mentioned cold storage facilities, when the door body swings in the opening direction due to product replenishment, product replacement, etc. and the front opening is opened, it allows the intrusion of moist air, and there is a risk of an increase in the amount of frost formation on the evaporator. Such an increase in the amount of frost formation on the evaporator leads to a decrease in cooling capacity, which is not preferable.

[0005] In view of the above situation, an object of the present invention is to provide a cooling device capable of reducing the amount of frost formation on the evaporator and suppressing a decrease in cooling capacity.

Means for Solving the Problems

[0006] To achieve the above objective, the cooling device according to the present invention comprises a refrigerant circuit configured by sequentially connecting an evaporator installed in a refrigeration facility, a compressor that sucks in and compresses the refrigerant evaporated in the evaporator, a condenser that condenses the refrigerant compressed by the compressor, and an expansion mechanism that adiabatically expands the refrigerant condensed in the condenser, via a refrigerant pipeline, and cools the internal air of a cold storage unit constituting the refrigeration facility by circulating the refrigerant in the refrigerant circuit, characterized in that it comprises an inlet temperature detection means for detecting the refrigerant inlet temperature, which is the refrigerant temperature at the inlet of the evaporator, and a control unit that drives the compressor so that the refrigerant inlet temperature detected by the inlet temperature detection means approaches a target evaporation temperature near 0°C, provided that the conditions for opening an opening formed in the refrigeration facility and facing the cold storage unit are met.

[0007] Furthermore, the present invention provides a cooling device that includes a blowing means installed in the equipment requiring cooling and for blowing air cooled by the evaporator into the cold storage unit, wherein the control unit reduces the amount of air blown by the blowing means to the minimum necessary size, provided that the conditions for opening the opening of the opening are met.

[0008] Furthermore, the present invention is characterized in that the cooling device is provided with an opening / closing detection means for detecting the opening or closing of the opening, and the control unit determines that the condition for opening the opening is met when the opening / closing detection means detects the opening of the opening.

[0009] Furthermore, the present invention provides a cooling device comprising an internal temperature detection means for detecting the internal temperature of the refrigerator, wherein the control unit, when the opening / closing detection means detects the closing of the opening after detecting the opening of the opening, drives the compressor so that the refrigerant inlet temperature approaches the target evaporation temperature, and, on the condition that the internal temperature detected by the internal temperature detection means is below a predetermined opening / closing operation completion threshold, drives the compressor so that the internal temperature approaches a predetermined target internal temperature.

[0010] Furthermore, the present invention is characterized in that, in the above-mentioned cooling device, the control unit increases the amount of air blown by the air blowing means when the opening / closing detection means detects the closing of the opening after detecting the opening of the opening.

[0011] Furthermore, the present invention is characterized in that, in the above-mentioned cooling device, the control unit performs a defrosting operation to remove frost adhering to the evaporator, then drives the compressor so that the refrigerant inlet temperature approaches the target evaporation temperature, and, on the condition that the internal temperature detected by the internal temperature detection means falls below a predetermined opening / closing operation termination threshold, drives the compressor so that the internal temperature approaches a preset target internal temperature.

[0012] Furthermore, the present invention is characterized in that, in the above-mentioned cooling device, the control unit adjusts the opening degree of the electronic expansion valve constituting the expansion mechanism so that the superheating degree, which is the difference between the refrigerant temperature at the outlet of the evaporator and the refrigerant temperature at the inlet of the evaporator, approaches a predetermined target superheating degree, regardless of whether the opening is open or closed. [Effects of the Invention]

[0013] According to the present invention, the inlet temperature detection means detects the refrigerant inlet temperature, which is the refrigerant temperature at the inlet of the evaporator, and the control unit, provided that the conditions for opening the opening formed in the refrigeration equipment and facing the cold storage are met, drives the compressor so that the refrigerant inlet temperature detected by the inlet temperature detection means approaches the target evaporation temperature near 0°C. This has the effect of reducing the amount of frost on the evaporator and suppressing a decrease in cooling capacity. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram showing a cooling device according to an embodiment of the present invention. [Figure 2] Figure 2 is a block diagram showing a characteristic control system of a cooling device according to an embodiment of the present invention. [Figure 3] Figure 3 is a flowchart showing the processing details of the compressor operation process associated with the opening and closing of the front opening, which is performed by the control unit shown in Figure 2. [Figure 4] Figure 4 is a flowchart showing the processing details of the operation of the internal fan associated with the opening and closing of the front opening, which is performed by the control unit shown in Figure 2. [Modes for carrying out the invention]

[0015] A preferred embodiment of the cooling device according to the present invention will be described in detail below with reference to the attached drawings.

[0016] Figures 1 and 2 show a cooling device that is an embodiment of the present invention, with Figure 1 being a schematic diagram and Figure 2 being a block diagram of a characteristic control system. The cooling device illustrated here comprises a refrigerant circuit 10 and a control unit 30.

[0017] The refrigerant circuit 10 is a circuit composed of a compressor 11, a condenser 12, an expansion mechanism 13, and an evaporator 14 connected sequentially by a refrigerant pipeline 15, and is filled with refrigerant. The compressor 11 is installed in a machine room 3 located inside the main body 2 of the equipment that constitutes the goods storage device (refrigerated equipment). This compressor 11 is driven in response to commands given by the control unit 30, and when driven, it sucks in refrigerant, compresses it, and discharges it as high-temperature, high-pressure refrigerant.

[0018] The condenser 12 is installed in the machine room 3, similar to the compressor 11. This condenser 12 condenses the refrigerant compressed by the compressor 11 by exchanging heat with the surrounding air. The expansion mechanism 13 consists of an electronic expansion valve 13a and a capillary tube 13b. The electronic expansion valve 13a can change its opening degree according to commands given by the control unit 30 and adiabatically expands the refrigerant condensed in the condenser 12. The capillary tube 13b is used to further reduce the pressure of the refrigerant that has been adiabatically expanded by the electronic expansion valve 13a.

[0019] The evaporator 14 is installed in the air passage 4 of the apparatus main body 2. This air passage 4 communicates with a cold storage 5 for storing goods through a suction port and a blowout port (both not shown), and circulates air between the cold storage 5 by driving an indoor fan (air blowing means) 18 installed in the air passage 4.

[0020] Here, the cold storage 5 stores goods by arranging modules for accommodating goods side by side vertically, horizontally, and in the front-rear direction, and faces the front opening 2a of the apparatus main body 2. This front opening 2a is opened and closed by a front door 6.

[0021] The evaporator 14 evaporates the refrigerant by heat-exchanging the refrigerant adiabatically expanded by the expansion mechanism 13 with the ambient air around itself, and sucks the refrigerant into the compressor 11. This evaporator 14 cools the air passing through the air passage 4 when the refrigerant evaporates, and cools the internal air of the cold storage 5 by being blown by the indoor fan 18, thereby cooling the goods stored in each module.

[0022] [[ID=I12]]The control unit 30 is connected to the compressor 11, the electronic expansion valve 13a, and the indoor fan 18 described above, and is also connected to an opening / closing detection unit 21, an indoor temperature detection unit 22, a refrigerant inlet temperature detection unit 23, and a refrigerant outlet temperature detection unit 24.

[0023] The opening / closing detection unit 21 is installed near the front opening 2a of the apparatus main body 2, and is an opening / closing detection means for detecting the opening and closing of the front opening 2a. This opening / closing detection unit 21 outputs the detection result as a detection signal to the control unit 30.

[0024] <0000I01>The indoor temperature detection unit 22 is installed inside the cold storage 5, and is an indoor temperature detection means for detecting the indoor temperature of the cold storage 5. This indoor temperature detection unit 22 continuously detects the indoor temperature, and outputs the detection result as a detection signal to the control unit 30.

[0025] The refrigerant inlet temperature detection unit 23 is installed near the inlet of the evaporator 14 in the refrigerant circuit 10 and is an inlet temperature detection means that detects the temperature of the refrigerant passing through the inlet of the evaporator 14, i.e., the refrigerant inlet temperature. This refrigerant inlet temperature detection unit 23 continuously detects the refrigerant inlet temperature and outputs the detection result as a detection signal to the control unit 30.

[0026] The refrigerant outlet temperature detection unit 24 is installed near the outlet of the evaporator 14 in the refrigerant circuit 10 and is an outlet temperature detection means that detects the temperature of the refrigerant passing through the outlet of the evaporator 14, i.e., the refrigerant outlet temperature. This refrigerant outlet temperature detection unit 24 continuously detects the refrigerant outlet temperature and outputs the detection result as a detection signal to the control unit 30.

[0027] The control unit 30 comprehensively controls the operation of each part of the cooling system according to the programs and data stored in the memory unit 40, which is connected in the same way as the compressor 11, and is characterized by comprising an input processing unit 31, a determination processing unit 32, and an output processing unit 33.

[0028] The input processing unit 31 processes signals from each unit connected to the control unit 30, and in particular processes detection signals from the open / close detection unit 21, the internal temperature detection unit 22, the refrigerant inlet temperature detection unit 23, and the refrigerant outlet temperature detection unit 24.

[0029] The determination processing unit 32 compares the detection result (current internal temperature) from the internal temperature detection unit 22, which has been processed as input via the input processing unit 31, with the opening / closing operation completion threshold read from the storage unit 40, and determines whether the internal temperature is below the opening / closing operation completion threshold. Here, the "opening / closing operation completion threshold" is stored in advance in the storage unit 40 and, as will be described in detail later, is a threshold that defines the termination of the operation of the compressor 11 and the operation of the internal fan 18 when the front opening 2a is opened and closed by the front door 6.

[0030] The output processing unit 33 includes a compressor drive processing unit 33a, a valve opening adjustment processing unit 33b, and an internal fan drive processing unit 33c.

[0031] The compressor drive unit 33a outputs a drive signal to the compressor 11 to drive the compressor 11 at a predetermined rotational speed. The valve opening adjustment unit 33b adjusts the opening of the electronic expansion valve 13a, which constitutes the expansion mechanism 13, by increasing or decreasing its opening. The internal fan drive unit 33c outputs a drive signal to the internal fan 18 to drive the internal fan 18 at a predetermined airflow rate.

[0032] Furthermore, the control unit 30 may be implemented, for example, by causing a processing unit such as a CPU (Central Processing Unit) to execute a program, i.e., by software; by hardware such as an IC (Integrated Circuit); or by using a combination of software and hardware.

[0033] In a cooling device having the above configuration, when cooling products stored in the refrigerator 5 with the front opening 2a of the device body 2 closed by the front door 6, the control unit 30 drives the compressor 11, the electronic expansion valve 13a, and the internal fan 18 as follows.

[0034] The compressor 11 will now be described. The control unit 30 controls the rotational speed of the compressor 11 via the compressor drive unit 33a so that the detection result (current value of the internal temperature) from the internal temperature detection unit 22, which is processed as input via the input processing unit 31, approaches a preset target value for the internal temperature (target internal temperature value).

[0035] The electronic expansion valve 13a will now be described. The control unit 30 adjusts the opening degree of the electronic expansion valve 13a via the valve opening degree adjustment processing unit 33b so that the superheat degree, which is the difference between the detection result of the refrigerant outlet temperature detection unit 24 (refrigerant outlet temperature) and the detection result of the refrigerant inlet temperature detection unit 23 (refrigerant inlet temperature) that has been processed as input via the input processing unit 31, approaches a predetermined target superheat degree.

[0036] The internal fan 18 will now be described. The control unit 30 adjusts the airflow of the internal fan 18 via the internal fan drive unit 33c so that the airflow is of a predetermined size, for example, about 70-90% of the maximum value.

[0037] As a result, the refrigerant, which is compressed in the compressor 11 and condensed in the condenser 12, undergoes adiabatic expansion in the expansion mechanism 13 before flowing to the evaporator 14, where it exchanges heat with the surrounding air and evaporates, and is then drawn back into the compressor 11. In this way, the evaporation of the refrigerant in the evaporator 14 cools the air circulating between the refrigerator 5 and the air passage 4 by driving the internal fan 18, thereby cooling the products inside the refrigerator 5.

[0038] In the cooling device used to cool the products stored in the refrigerator 5 as described above, the front opening 2a is opened and closed by the front door 6, thereby operating the compressor 11 and the internal fan 18 as follows.

[0039] Figure 3 is a flowchart showing the processing details of the operation of the compressor 11 associated with the opening and closing of the front opening 2a, which is performed by the control unit 30 shown in Figure 2.

[0040] The control unit 30 processes the detection result of the opening / closing detection unit 21 through the input processing unit 31 to determine whether or not the opening / closing detection unit 21 has detected the opening of the front opening 2a (step S101).

[0041] If opening of the front opening 2a is not detected (step S101: No), the control unit 30 will terminate the current process without performing the process described later, that is, by maintaining the current control of the rotational speed of the compressor 11.

[0042] If the opening of the front opening 2a is detected (step S101: Yes), the control unit 30 assumes that the condition for opening the front opening 2a is met and controls the rotation speed of the compressor 11 via the compressor drive unit 33a so that the detection result from the refrigerant inlet temperature detection unit 23 (current value of the refrigerant inlet temperature), which has been processed as input via the input processing unit 31, approaches a preset target value for the evaporation temperature (for example, near 0°C) (step S102). As a result, when the front opening 2a is open, refrigerant at near 0°C flows to the evaporator 14 in the refrigerant circuit 10.

[0043] The control unit 30, which carries out the processing in step S102, receives the detection result from the opening / closing detection unit 21 as input processing through the input processing unit 31 and waits for the opening / closing detection unit 21 to detect that the front opening 2a has closed (step S103).

[0044] If the closure of the front opening 2a is detected (step S103: Yes), the control unit 30 continues the process of step S102. That is, the control unit 30 controls the rotational speed of the compressor 11 via the compressor drive processing unit 33a so that the detection result from the refrigerant inlet temperature detection unit 23, which has been processed as input via the input processing unit 31 (current value of the refrigerant inlet temperature), approaches a preset target value of the evaporation temperature (for example, near 0°C) (step S104).

[0045] Then, the control unit 30, through the determination processing unit 32, determines whether the current value of the internal temperature from the internal temperature detection unit 22, which has been processed as input via the input processing unit 31, is equal to or greater than the opening / closing operation completion threshold read from the storage unit 40 (step S105).

[0046] If the current internal temperature exceeds the threshold for the end of the opening / closing operation (step S105: No), the control unit 30 repeats the processes of steps S104 and S105.

[0047] On the other hand, if the current internal temperature is below the opening / closing operation completion threshold (step S105: Yes), the control unit 30 controls the rotation speed of the compressor 11 via the compressor drive processing unit 33a so that the detection result (current internal temperature) from the internal temperature detection unit 22, which has been processed as input via the input processing unit 31, approaches the target internal temperature (step S106), and then terminates the current process.

[0048] Figure 4 is a flowchart showing the processing details of the operation of the internal fan 18 in conjunction with the opening and closing of the front opening 2a, which is performed by the control unit 30 shown in Figure 2.

[0049] The control unit 30 processes the detection result of the opening / closing detection unit 21 through the input processing unit 31 to determine whether or not the opening / closing detection unit 21 has detected the opening of the front opening 2a (step S201). If the opening of the front opening 2a is not detected (step S201: No), the control unit 30 terminates the current process without performing the processing described later, that is, by maintaining the current airflow rate of the internal fan 18.

[0050] If opening of the front opening 2a is detected (step S201: Yes), the control unit 30 determines that the condition for opening the front opening 2a has been met and reduces the airflow volume through the internal fan drive unit 33c to the minimum necessary size, for example, about 30-50% of the maximum size (step S202).

[0051] The control unit 30, which carries out the processing in step S202, receives the detection result from the opening / closing detection unit 21 as input processing through the input processing unit 31 and waits for the opening / closing detection unit 21 to detect that the front opening 2a has closed (step S203).

[0052] If the closing of the front opening 2a is detected (step S203: Yes), the control unit 30 increases the airflow rate through the internal fan drive unit 33c so that the airflow rate becomes a predetermined size, for example, about 70-100% of the maximum value (step S204).

[0053] Then, the control unit 30, through the determination processing unit 32, determines whether the current value of the internal temperature from the internal temperature detection unit 22, which has been processed as input via the input processing unit 31, is equal to or greater than the opening / closing operation completion threshold read from the storage unit 40 (step S205).

[0054] If the current internal temperature exceeds the threshold for the end of the opening / closing operation (step S205: No), the control unit 30 repeats the processing in steps S204 and S205.

[0055] On the other hand, if the current temperature inside the storage compartment is below the threshold for the opening and closing operation (step S205: Yes), the control unit 30 adjusts the airflow rate of the storage compartment fan 18 to a predetermined size via the storage compartment fan drive unit 33c (step S206), and then terminates the current process.

[0056] Here, regarding the adjustment of the airflow rate of the internal fan 18 in step S206, the airflow rate of the internal fan 18 may be set to the same level as in step S204, or it may be set to an intermediate level between step S202 and step S204.

[0057] Furthermore, with respect to the electronic expansion valve 13a, regardless of whether the front opening 2a is opened by the opening / closing detection unit 21, the opening degree of the electronic expansion valve 13a is adjusted via the valve opening degree adjustment processing unit 33b so that the superheating degree approaches the target superheating degree, as described above.

[0058] As described above, according to the cooling device of the present invention, the control unit 30 drives the compressor 11 so that the current value of the refrigerant inlet temperature approaches a target value (target evaporation temperature value) near 0°C, provided that the opening of the front opening 2a is detected by the opening / closing detection unit 21. This reduces the amount of frost on the evaporator 14 and suppresses a decrease in cooling capacity.

[0059] According to the above cooling system, the control unit 30 reduces the amount of air blown by the internal fan 18 to the minimum necessary size, provided that the opening of the front opening 2a is detected by the opening / closing detection unit 21. This suppresses the occurrence of liquid back, where the refrigerant is sucked into the compressor 11 in a liquid phase state, while also reducing the amount of humid outside air entering through the front opening 2a, thereby suppressing the temperature rise of the products.

[0060] According to the above cooling device, when the front opening 2a is detected to be closed after the opening detection unit 21 has detected the opening of the front opening 2a, the control unit 30 drives the compressor 11 so that the current value of the refrigerant inlet temperature approaches a target value near 0°C until the current value of the internal temperature falls below the threshold for completion of the opening operation. This also reduces the amount of frost on the evaporator 14 and suppresses a decrease in cooling capacity.

[0061] According to the above cooling device, when the front opening 2a is detected to be closed after the opening detection unit 21 has detected that the front opening 2a has been opened, the control unit 30 increases the airflow from the internal fan 18 to a predetermined size, for example, about 70-100% of the maximum value, thereby also suppressing the temperature rise of the product.

[0062] Although preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made.

[0063] In the above-described embodiment, the condition for opening the front opening 2a was met by the detection of the opening of the front opening 2a by the opening / closing detection unit 21. However, in the present invention, the condition for opening the front opening 2a may be met regardless of the detection by the opening / closing detection unit 21, if the internal temperature detected by the internal temperature detection unit 22 continues to rise for a predetermined period of time.

[0064] Although not specifically mentioned in the embodiments described above, the processes of steps S104 to S106 in the compressor drive control process may be performed after a defrosting operation to remove frost adhering to the evaporator 14. That is, the control unit 30 may drive the compressor 11 so that the current value of the refrigerant inlet temperature approaches the target evaporation temperature after the defrosting operation, and then drive the compressor 11 so that the internal temperature approaches the target internal temperature, provided that the current value of the internal temperature detected by the internal temperature detection unit 22 is below the opening / closing operation completion threshold.

[0065] By driving the compressor 11 so that the refrigerant inlet temperature approaches the target evaporation temperature after the defrosting operation, even if a relatively large amount of frost accumulates and water droplets remain on the surface of the fins and other components of the evaporator 14 after the defrosting operation, re-frosting due to these water droplets can be suppressed, thereby preventing a decrease in cooling capacity.

[0066] In the above-described embodiment, an article storage device having one refrigerator compartment 5 was explained. However, in the present invention, an article storage device may also be applied to a device body in which multiple refrigerator compartments are provided, and each refrigerator compartment has a corresponding front door. In this case, an expansion mechanism and an evaporator are installed in relation to each refrigerator compartment, and these expansion mechanisms and evaporators are connected in parallel to the compressor and condenser to form a refrigerant circuit.

[0067] In the embodiment described above, the expansion mechanism 13 included an electronic expansion valve 13a and a capillary tube 13b, but in the present invention, the expansion mechanism may consist only of an electronic expansion valve.

[0068] In the embodiments described above, an article storage device was given as an example of a refrigerated equipment, but in the present invention, a showcase may also be used as the refrigerated equipment. [Explanation of symbols]

[0069] 2...Main unit, 2a...Front opening, 5...Refrigerator compartment, 6...Front door, 10...Refrigerant circuit, 11...Compressor, 12...Condenser, 13...Expansion mechanism, 13a...Electronic expansion valve, 13b...Capillary tube, 14...Evaporator, 15...Refrigerant line, 18...Internal fan, 21...Open / close detection unit, 22...Internal temperature detection unit, 23...Refrigerant inlet temperature detection unit, 24...Refrigerant outlet temperature detection unit, 30...Control unit, 31...Input processing unit, 32...Determination processing unit, 33...Output processing unit, 33a...Compressor drive processing unit, 33b...Valve opening adjustment processing unit, 33c...Internal fan drive processing unit, 40...Storage unit.

Claims

1. The refrigerant circuit is configured by sequentially connecting an evaporator installed in the refrigeration equipment, a compressor that sucks in and compresses the refrigerant evaporated in the evaporator, a condenser that condenses the refrigerant compressed by the compressor, and an expansion mechanism that adiabatically expands the refrigerant condensed in the condenser, via a refrigerant pipeline. A cooling device that cools the internal air of a cold storage unit constituting the refrigeration equipment by circulating a refrigerant in the aforementioned refrigerant circuit, An inlet temperature detection means for detecting the refrigerant inlet temperature, which is the refrigerant temperature at the inlet of the evaporator, A control unit drives the compressor so that the refrigerant inlet temperature detected by the inlet temperature detection means approaches the target evaporation temperature near 0°C, provided that the conditions for opening the opening formed in the refrigeration equipment and facing the cold storage unit are met. A cooling device characterized by having the following features.

2. The aforementioned refrigeration equipment is equipped with a blowing means for supplying air cooled by the evaporator to the refrigerated storage unit, The cooling device according to claim 1, characterized in that the control unit reduces the amount of air blown by the air blowing means to the minimum necessary size, provided that the conditions for opening the opening of the opening are met.

3. The system includes an opening / closing detection means for detecting the opening and closing of the aforementioned opening, The cooling device according to claim 2, characterized in that the control unit determines that the condition for opening the opening is met when the opening / closing detection means detects the opening of the opening.

4. The refrigerator is equipped with an internal temperature detection means for detecting the internal temperature of the refrigerator, The cooling device according to claim 3, wherein the control unit, when the opening / closing detection means detects the closing of the opening after detecting the opening of the opening, drives the compressor so that the refrigerant inlet temperature approaches the target evaporation temperature, and, on the condition that the internal temperature detected by the internal temperature detection means is below a predetermined threshold for the completion of the opening / closing operation, drives the compressor so that the internal temperature approaches a predetermined target internal temperature.

5. The cooling device according to claim 4, characterized in that the control unit increases the amount of air blown by the air blowing means when the opening / closing detection means detects the closing of the opening after detecting the opening of the opening.

6. The cooling apparatus according to claim 5, wherein the control unit performs a defrosting operation to remove frost adhering to the evaporator, then drives the compressor so that the refrigerant inlet temperature approaches the target evaporation temperature, and, on the condition that the internal temperature detected by the internal temperature detection means is below a predetermined opening / closing operation termination threshold, drives the compressor so that the internal temperature approaches a predetermined target internal temperature.

7. The cooling apparatus according to claim 6, characterized in that the control unit adjusts the opening of the electronic expansion valve constituting the expansion mechanism so that the degree of superheating, which is the difference between the refrigerant temperature at the outlet of the evaporator and the refrigerant temperature at the inlet of the evaporator, approaches a predetermined target degree of superheating, regardless of whether the opening is open or closed.

Images