WO2023166907A1

WO2023166907A1 - Refrigeration device

Info

Publication number: WO2023166907A1
Application number: PCT/JP2023/003420
Authority: WO
Inventors: 匡司佐藤; 稔須藤; 淳大原
Original assignee: Ｐｈｃホールディングス株式会社
Priority date: 2022-03-03
Filing date: 2023-02-02
Publication date: 2023-09-07

Abstract

This refrigeration device comprises a first refrigerant circuit including a first compressor, a first condenser, a first expander, and a first evaporator, N (N is a natural number at least equal to 2) condenser coolers forming a flow of air for cooling the first condenser, and a control unit for individually controlling the N condenser coolers, wherein, if fewer than N condenser coolers are to be driven, the control unit selects and drives the condenser coolers having the shortest cumulative drive time.

Description

refrigeration equipment

The present disclosure relates to refrigeration equipment.

Conventionally, a configuration is known in which a plurality of condenser coolers for cooling condensers are arranged in a refrigeration system, and the number of condenser coolers to be driven is changed according to the situation (for example, Patent Document 1, 2).

Patent Literature 1 discloses a refrigeration system with three condenser fans. In the refrigeration system, the higher the outside air temperature is, the more condenser fans are operated.

Patent Literature 2 discloses a refrigeration system having first, second, and third outside fans. The first outside-compartment fan is configured so that the wind sent by the first outside-compartment fan does not directly hit the compressor. The second and third outside-compartment fans are configured so that the winds sent by the second and third outside-compartment fans directly hit the compressor. In the refrigerating apparatus, when the heat pump operation capability decreases while the first, second, and third outside fans are operating, the operation of the second and third outside fans is stopped, while the operation of the first outside fan is stopped. Continue to run the outside fan.

JP-A-10-2625 JP 2017-116253 A

However, in the configurations disclosed in

Patent Documents

1 and 2, since the condenser cooler to be driven is determined according to the situation, the integrated driving time of each condenser cooler varies, and the length of the condenser cooler is increased. Life cannot be extended.

An object of the present disclosure is to provide a refrigeration system capable of prolonging the life of a plurality of condenser coolers.

A refrigeration apparatus according to the present disclosure forms a first refrigerant circuit having a first compressor, a first condenser, a first expander, and a first evaporator, and an air flow that cools the first condenser. and a controller that individually controls the N condenser coolers, wherein the controller controls the condenser coolers that are less than the N condenser coolers. When the coolers are driven, the condenser cooler having the short cumulative driving time is selected and driven.

According to the refrigeration system of the present disclosure, it is possible to extend the life of the multiple condenser coolers.

The perspective view which shows the outline of the external appearance of a refrigeration apparatus. Block diagram showing the internal configuration of the refrigeration system Cross-sectional view showing arrangement of condenser fans Rear view showing arrangement of condenser fans Block diagram showing the control system of the refrigeration system Flowchart showing the operation of the refrigeration system Flowchart showing the operation of the refrigeration system

[Embodiment]
Embodiments of the present disclosure will be described below.

<Composition of Refrigerating Device>
First, the configuration of the refrigeration system will be described. FIG. 1 is a perspective view showing the outline of the appearance of a refrigeration system. FIG. 2 is a block diagram showing the internal configuration of the refrigeration system. FIG. 3 is a cross-sectional view showing an arrangement state of the condenser fan. FIG. 4 is a rear view showing the arrangement of condenser fans. FIG. 5 is a block diagram showing the control system of the refrigeration system. In the following, the front side is the side facing the user when using the refrigeration apparatus, and the rear side is the side opposite to the front side. Further, the right side is the right side as seen from the user facing the refrigerating apparatus, and the left side is the opposite side of the right side. The upper side is the upper side when the refrigerating apparatus is installed on a horizontal plane, and the lower side is the opposite side of the upper side.

The freezing device 1 shown in FIG. 1 is, for example, an ultra-low temperature freezer capable of cooling articles to -80°C or lower. The refrigerator 1 includes a storage section 11 , an operation display section 12 and a machine room 13 .

The storage section 11 is arranged above the machine room 13 . The storage unit 11 includes a box 111 having an opening on the front surface and a door 112 closing the opening of the box 111 . The box 111 has a heat-insulating structure and is configured so that articles housed therein can be stored at a freezing temperature. The door 112 is attached to one side edge of the box 111 via a hinge, for example, so that it can be opened and closed.

The operation display unit 12 is arranged in front of the door 112, for example. The operation display unit 12 has a function as an operation unit used for inputting settings such as operating conditions of the refrigeration apparatus 1 and a function as a display unit for displaying various information regarding the operation of the refrigeration apparatus 1 . The operation display unit 12 may be configured by a touch panel having both functions of the operation unit and the display unit, or may be configured by buttons having the function of the operation unit and a display having the function of the display unit.

An air intake hole 131 is formed in the front surface of the machine room 13 for taking in outside air into the machine room 13 . An air discharge hole 132 (see FIG. 3) is formed in the rear surface of the machine room 13 for discharging the air inside the machine room 13 to the outside.

As shown in FIG. 2 , the refrigeration system 1 further includes a high temperature side refrigerant circuit 2 , a low temperature side refrigerant circuit 3 and a condenser cooling section 4 .

The high temperature side refrigerant circuit 2 is an example of the first refrigerant circuit of the present disclosure. The high temperature side refrigerant circuit 2 includes a first compressor 21 , a first condenser 22 , a first expander 23 and a first evaporator 24 .

The low temperature side refrigerant circuit 3 is an example of the second refrigerant circuit of the present disclosure. The low temperature side refrigerant circuit 3 includes a second compressor 31 , a second condenser 32 , a second expander 33 and a second evaporator 34 . The second condenser 32 constitutes a cascade condenser 25 together with the first evaporator 24 .

The condenser cooling section 4 forms an air flow that cools the first condenser 22 . The condenser cooling unit 4 includes N (N is a natural number of 2 or more) condenser fans 40 . The condenser fan 40 is an example of the condenser cooler of the present disclosure. In this embodiment, the condenser cooling unit 4 includes a first condenser fan 41 , a second condenser fan 42 , a third condenser fan 43 , and a fourth condenser fan 44 . In this embodiment, the configuration in which the condenser cooling unit 4 includes four condenser fans 40 is exemplified. good. Further, in FIG. 2, the first to fourth condenser fans 41 to 44 are shown to be arranged in a line in order to represent the number of the first to fourth condenser fans 41 to 44. are arranged in two stages, upper and lower, as shown in FIG.

The first compressor 21 and the second compressor 31 are, for example, rotary compressors. As shown in FIG. 3 , the first compressor 21 and the second compressor 31 are arranged side by side on the rear side in the machine room 13 . The first compressor 21 and the second compressor 31 are arranged at positions facing the air discharge holes 132 . The first condenser 22 is arranged at a position facing the air intake hole 131 on the front side in the machine room 13 .

The first to fourth condenser fans 41 to 44 are arranged between the first condenser 22 and the first and

second compressors

21 and 31 . As shown in FIG. 4, the first and

second condenser fans

41 and 42 are arranged side by side. The third and

fourth condenser fans

43 and 44 are arranged side by side below the first and

second condenser fans

41 and 42, respectively. By driving the first to fourth condenser fans 41 to 44 simultaneously, the external air A can be taken in from the air intake hole 131 and the taken in air A can be led to the entire first compressor 21. are arranged as

In the configuration as described above, the first compressor 21 of the high-temperature side refrigerant circuit 2 compresses the first refrigerant and discharges high-temperature, high-pressure gas refrigerant. The first condenser 22 cools and discharges the first refrigerant discharged from the first compressor 21 . The first to fourth condenser fans 41 to 44 take in the outside air A from the air intake hole 131, and pass the taken in air A through the first condenser 22. to cool. Cooling of the first condenser 22 by the first to fourth condenser fans 41 to 44 promotes cooling of the first refrigerant passing through the first condenser 22 . The first to fourth condenser fans 41 to 44 guide the air A used for cooling the first compressor 21 to the first and

second compressors

21 and 31, so that the first and

second compressors

21, 31 are cooled. The air A used for cooling the first and

second compressors

21 and 31 is discharged outside through the air discharge holes 132 . The first expander 23 reduces the pressure of the first refrigerant discharged from the first condenser 22 and discharges it. The first evaporator 24 evaporates the first refrigerant discharged from the first expander 23 and discharges it to the first compressor 21 .

The second compressor 31 of the low temperature side refrigerant circuit 3 compresses a second refrigerant having a boiling point lower than that of the first refrigerant and discharges it as a high temperature and high pressure gas refrigerant. The second condenser 32 condenses and discharges the second refrigerant discharged from the second compressor 31 . The second refrigerant passing through the second condenser 32 is cooled by the endothermic action of the first refrigerant in the first evaporator 24 and is discharged in a medium temperature and high pressure state. The second expander 33 reduces the pressure of the second refrigerant discharged from the second condenser 32 and discharges it. The second evaporator 34 evaporates the second refrigerant discharged from the second expander 33 and discharges it to the second compressor 31 . Due to the endothermic effect when the second refrigerant evaporates in the second evaporator 34, the heat in the storage section 11 moves to the second evaporator 34, thereby cooling the storage section 11. FIG.

As shown in FIG. 5, the refrigeration apparatus 1 includes a cascade temperature detection unit 50, an internal temperature detection unit 51, an outside air temperature detection unit 52, a timer unit 53, a storage unit 54, a control unit 55, Further prepare.

The cascade temperature detection unit 50 detects the temperature of the cascade capacitor 25 and outputs a signal corresponding to the detected temperature. The internal temperature detection unit 51 detects the temperature inside the storage unit 11 and outputs a signal corresponding to the detected temperature. The outside temperature detection unit 52 detects the outside temperature outside the refrigeration apparatus 1 and outputs a signal corresponding to the detected outside temperature. The clock unit 53 clocks the driving time of the first to fourth condenser fans 41 to 44 .

The storage unit 54 is configured to be able to transmit and receive information to and from the control unit 55. The storage unit 54 stores the driving time of each condenser fan 40 . Note that the storage unit 54 may store an integrated driving time, which is an integrated value of the driving time, for each condenser fan 40 . The storage unit 54 stores information necessary for controlling the refrigeration system 1 .

The control unit 55 has a CPU (Central Processing Unit), and the CPU executes a control program stored in the storage unit 54 to realize the functions of the control unit 55 . The control unit 55 includes a cascade temperature detection unit 50, an internal temperature detection unit 51, an outside air temperature detection unit 52, a clock unit 53, an operation display unit 12, first and

second compressors

21 and 31, Various signals can be transmitted and received between the first to fourth condenser fans 41 to 44 .

The control unit 55 individually controls the first to fourth condenser fans 41 to 44. When the condenser fan 40 is driven, the control unit 55 acquires the time measurement result from the time measurement unit 53 , calculates the driving time of the condenser fan 40 , and stores it in the storage unit 54 . When one or more of the less than four condenser fans 40 are to be driven, the control unit 55 selects the condenser fan 40 with the short cumulative driving time based on the driving time stored in the storage unit 54 . The controller 55 drives the selected condenser fan 40 .

<Operation of Refrigerating Device>
Next, the operation of the refrigeration system 1 will be described. 6 and 7 are flow charts showing the operation of the refrigeration system.

In a state where the first and

second compressors

21 and 31 are stopped, when the user operates the operation display unit 12 to input a setting for starting the operation of the refrigerating apparatus 1, the operation shown in FIG. Thus, the controller 55 starts driving all the condenser fans 40 (step S1). Also, the control unit 55 starts the operation of the refrigeration system 1 (step S2). Cooling in the storage section 11 is started by the processing of steps S1 and S2. In the process of step S<b>2 , the control unit 55 first starts driving the first compressor 21 . When the temperature of the cascade capacitor 25 based on the signal from the cascade temperature detection unit 50 becomes equal to or lower than a predetermined temperature, the control unit 55 continues driving the first compressor 21 and starts driving the second compressor 31. .

After that, the control unit 55 determines whether or not to start normal operation for cooling the inside of the storage unit 11 at the target temperature (step S3). In the processing of step S3, the control unit 55 determines to start normal operation when the temperature in the storage unit 11 based on the signal from the internal temperature detection unit 51 has decreased to the target temperature, and the temperature has decreased to the target temperature. If not, it is determined not to start normal operation. If the controller 55 determines not to start the normal operation (step S3: NO), the process of step S3 is performed again after a predetermined period of time has elapsed. On the other hand, when determining to start normal operation (step S3: YES), the control unit 55 calculates the integrated drive time until it is determined to start normal operation in each condenser fan 40 (step S4).

Next, the control unit 55 selects the condenser fan 40 to be driven during normal operation based on the cumulative drive time and the outside temperature detected by the outside temperature detection unit 52 (step S5). In the process of step S5, the controller 55 first determines the number of condenser fans 40 to be driven based on the outside air temperature. The control unit 55 increases the number of the condenser fans 40 to be driven as the outside air temperature increases, for example, based on information representing the relationship between the outside air temperature and the number of the condenser fans 40 . Next, the control unit 55 selects the condenser fan 40 to be driven during normal operation from among the four condenser fans 40 in descending order of the cumulative drive time. For example, when selecting three condenser fans 40 , the control unit 55 selects the condenser fans 40 with the first, second, and third shortest cumulative drive times, and selects two condenser fans 40 . In this case, the condenser fan 40 with the first and second shortest integrated drive times is selected. If there are a plurality of condenser fans 40 with the same integrated driving time, the controller 55 selects the condenser fan 40 to be driven during normal operation based on a preset criterion. For example, the control unit 55 selects the lower condenser fan 40 among the plurality of condenser fans 40 having the same integrated drive time. Further, in the process of step S5, the control unit 55 may select all the condenser fans 40 as the condenser fans 40 to be driven during normal operation when the outside air temperature is high. Then, the controller 55 starts driving the selected condenser fan 40 (step S6).

After that, the control unit 55 determines whether or not to change the number of condenser fans 40 to be driven during normal operation based on the outside air temperature (step S7). In the process of step S7, the control unit 55 determines whether or not the number of condenser fans 40 needs to be increased because the outside air temperature has risen after the start of driving the condenser fans 40 in step S6. It is determined whether or not the number of condenser fans 40 can be reduced because the number of condenser fans 40 has decreased. When the control unit 55 determines that the number of condenser fans 40 to be driven is to be changed based on the outside air temperature (step S7: YES), the control unit 55 performs the processes of steps S4 to S6 to increase the number of condenser fans 40 to be driven during normal operation. The number of fans 40 is changed.

On the other hand, when the controller 55 determines not to change the number of condenser fans 40 to be driven based on the outside air temperature (step S7: NO), it determines whether or not to suspend normal operation (step S8). ). In the processing of step S8, the control unit 55 determines that the normal operation is to be temporarily suspended because the storage unit 11 does not need to be further cooled when the temperature inside the storage unit 11 becomes lower than the first threshold temperature. The first threshold temperature is set to a temperature equal to or lower than the target temperature. When the control unit 55 determines not to suspend the normal operation (step S8: NO), it performs the process of step S7.

On the other hand, when the control unit 55 determines to suspend the normal operation (step S8: YES), as shown in FIG. Stop (step S9). Next, the control unit 55 calculates the integrated driving time until it is determined that the normal operation of each condenser fan 40 is to be temporarily stopped (step S10). Then, the control unit 55 selects one condenser fan 40 to be driven at the time of temporary stop based on the integrated driving time (step S11). In the process of step S11, the control unit 55 selects the condenser fan 40 with the shortest integrated driving time from among the four condenser fans 40 as the condenser fan 40 to be driven during the temporary stop. Then, the controller 55 starts driving the selected condenser fan 40 (step S12). In this way, the first and

second compressors

21 and 31 can be quickly cooled by driving one condenser fan 40 instead of stopping all the condenser fans 40 at the time of temporary stop. can.

After that, the control unit 55 determines whether or not to resume normal operation (step S13). In the process of step S13, when the temperature inside the storage unit 11 becomes equal to or higher than the second threshold temperature, the control unit 55 determines that the normal operation should be resumed because the storage unit 11 needs to be cooled. The second threshold temperature is set to a temperature equal to or higher than the target temperature. When the control unit 55 determines not to resume normal operation (step S13: NO), the process of step S13 is performed again after a predetermined period of time has elapsed.

On the other hand, when determining to resume normal operation (step S13: YES), the control unit 55 starts driving the first and

second compressors

21 and 31 to resume operation of the refrigeration system 1 (step S14). ). After that, the control unit 55 performs the process of step S4 shown in FIG. The control unit 55 performs the processing based on the flowcharts of FIGS. 6 and 7 until the user inputs a setting to stop the operation of the refrigeration apparatus 1 .

As described above, when less than four condenser fans 40 are to be driven, the control unit 55 selects the condenser fan 40 having a short cumulative driving time instead of driving a predetermined condenser fan 40. Select and drive. Therefore, it is possible to suppress the occurrence of variations in the integrated driving time of each condenser fan 40, and it is not possible to extend the life of the condenser fan 40. FIG.

[Modification of Embodiment]
It goes without saying that the present disclosure is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the present disclosure. The above-described embodiment and modifications shown below may be combined in any manner within the applicable range.

For example, the configuration of the present disclosure, which selects and drives the condenser fan 40 with a short integrated drive time, may be applied to a refrigeration system that includes only the high temperature side refrigerant circuit 2 . In this case, the first evaporator 24 cools the inside of the storage section 11 without configuring the cascade condenser 25 .

Although the configuration in which the condenser fan 40 with the shortest cumulative drive time is selected and driven at the start of normal operation of the refrigeration system 1 is illustrated, all the condenser fans 40 are driven regardless of the cumulative drive time and the outside air temperature. Also good.

Although the configuration for changing the number of condenser fans 40 to be driven at the start of normal operation based on the outside air temperature after the normal operation of the refrigerating apparatus 1 is started, such a number change process can be performed regardless of the outside air temperature. You can choose not to do it.

Although the configuration for selecting and driving one condenser fan 40 with a short cumulative drive time when the normal operation of the refrigeration apparatus 1 is temporarily stopped has been illustrated, not all the condenser fans 40 need to be driven, Two or three condenser fans 40 with short integrated drive times may be selected and driven.

The refrigerating apparatus of the present disclosure is not limited to ultra-low temperature freezers, but may be biomedical freezers, showcases, refrigerated warehouses, refrigerator trucks, or refrigerating apparatuses such as ice machines. In addition, the cooling temperature obtained by the refrigerating device is, for example, 0 ° C. or lower, -40 ° C. or lower, or by selecting a refrigerant whose boiling point is 0 ° C. or lower, -40 ° C. or lower, or -80 ° C. or lower. -80°C or lower. Furthermore, the cooling temperature obtained by the refrigerating device may be as low as −150° C. or lower.

The disclosure contents of the specification, claims, drawings and abstract contained in the Japanese application of Japanese Patent Application No. 2022-032432 filed on March 3, 2022 are incorporated herein by reference.

The present disclosure can be applied to refrigeration equipment.

REFERENCE SIGNS LIST 1 refrigeration device 2 high-temperature side refrigerant circuit 3 low-temperature side refrigerant circuit 4 condenser cooling section 11 storage section 12 operation display section 13 machine room 21 first compressor 22 first condenser 23 first expander 24 first evaporator 25 cascade Condenser 31 Second compressor 32 Second condenser 33 Second expander 34 Second evaporator 40 Condenser fan 41 First condenser fan 42 Second condenser fan 43 Third condenser fan 44 Fourth condenser fan 50 Cascade temperature detection unit 51 internal temperature detection unit 52 outside air temperature detection unit 53 timer unit 54 storage unit 55 control unit 111 box 112 door 131 air intake hole 132 air discharge hole

Claims

a first refrigerant circuit having a first compressor, a first condenser, a first expander, and a first evaporator;
N (N is a natural number of 2 or more) condenser coolers that form an air flow for cooling the first condenser;
a control unit that individually controls the N condenser coolers,
The control unit
When less than N units of the condenser coolers are driven, the condenser cooler with a short cumulative drive time is selected and driven;
refrigeration equipment.
further comprising a second refrigerant circuit having a second compressor, a second condenser forming a cascade condenser with the first evaporator, a second expander, and a second evaporator;
Refrigeration equipment according to claim 1 .
a storage unit for storing articles;
an internal temperature detection unit that detects the temperature in the storage unit;
An outside temperature detection unit that detects the outside temperature outside the storage unit,
The control unit
In the normal operation for cooling the inside of the storage unit at the target temperature, when the lower the outside air temperature, the fewer the number of the condenser coolers are driven, the condenser cooler with the shorter cumulative drive time is selected and driven.
3. A refrigeration system according to claim 2.
The normal operation includes temporary stop processing for stopping the first compressor and the second compressor when the temperature in the storage unit is less than the first threshold temperature that is equal to or lower than the target temperature;
and an operation resuming process of driving the first compressor and the second compressor when the temperature in the storage unit becomes equal to or higher than a second threshold temperature equal to or higher than the target temperature,
The control unit
In the suspension process, when driving a smaller number of the condenser coolers than in the operation resumption process, the condenser cooler with a short cumulative drive time is selected and driven.
4. A refrigeration system according to claim 3.