WO2018142583A1

WO2018142583A1 - Refrigeration system

Info

Publication number: WO2018142583A1
Application number: PCT/JP2017/004012
Authority: WO
Inventors: 信吾谷中; ▲高▼田　茂生
Original assignee: 三菱電機株式会社
Priority date: 2017-02-03
Filing date: 2017-02-03
Publication date: 2018-08-09
Also published as: JPWO2018142583A1

Abstract

This refrigeration system is provided with a refrigerant circuit in which a compressor, a condenser, a flow path switching means, a dehumidifying heat exchanger, an expansion valve, and a cooler are connected by piping. The flow path switching means switches the flow path of a refrigerant between at least a first flow path in which refrigerant condensed by the condenser flows through the dehumidifying heat exchanger to the cooler, and a second flow path in which refrigerant evaporated by the cooler flows through the dehumidifying heat exchanger to the compressor.

Description

Refrigeration system

The present invention relates to a refrigeration system having a dehumidifying function.

Conventionally, in order to improve operation efficiency, an air conditioner that avoids defrosting and avoids frost formation on a heat absorber has been proposed (see, for example, Patent Document 1).

In the air conditioner described in Patent Document 1, frosting of the cooler is avoided by disposing an adsorbent having a dehumidifying effect on the windward side of the heat absorber. This air conditioner is applied to, for example, a freezer warehouse.

JP 2001-241893 A

The air conditioning apparatus described in Patent Document 1 uses air heated by a radiator to desorb moisture from the adsorbent, and it is necessary to discharge the humidified air outside the freezer warehouse. . However, taking air into and out of the refrigerated warehouse is not desirable from the viewpoint of operating efficiency because the temperature inside the warehouse rises.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a refrigeration system with improved operational efficiency without exhausting humidified air outside the room.

A refrigeration system according to the present invention includes a refrigerant circuit in which a compressor, a condenser, a flow path switching unit, a heat exchanger for dehumidification, an expansion valve, and a cooler are connected by piping, and the flow path switching unit includes a refrigerant A first flow path in which at least the refrigerant condensed in the condenser flows to the cooler through the dehumidifying heat exchanger, and the refrigerant evaporated in the cooler is in the dehumidifying heat exchange It switches to either of the 2nd flow paths which flow into the above-mentioned compressor via a vessel.

According to the refrigeration system according to the present invention, it is possible to improve the operation efficiency without exhausting humidified air to the outside.

It is the schematic explaining the structure of the refrigeration system which concerns on Embodiment 1 of this invention. It is a functional block diagram of the control apparatus of the refrigeration system which concerns on Embodiment 1 of this invention. It is a figure which shows the control flow at the time of operation | movement of the refrigerating system which concerns on Embodiment 1 of this invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the normal mode of the refrigerating system which concerns on Embodiment 1 of this invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the dehumidification mode of the refrigerating system which concerns on Embodiment 1 of this invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the defrost mode of the refrigeration system which concerns on Embodiment 1 of this invention. It is the schematic explaining the structure of the refrigeration system which concerns on Embodiment 2 of this invention. It is a figure which shows the control flow at the time of operation | movement of the refrigerating system which concerns on Embodiment 2 of this invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the dehumidification mode of the refrigerating system which concerns on Embodiment 2 of this invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the defrost mode of the refrigeration system which concerns on Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below. Moreover, in the following drawings, the relationship of the size of each component may be different from the actual one.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram illustrating a configuration of a refrigeration system 100 according to Embodiment 1 of the present invention.
Hereinafter, the configuration of the refrigeration system 100 according to the first embodiment will be described with reference to FIG. In the first embodiment, an example in which the refrigeration system 100 is applied to a refrigeration warehouse will be described.

(Equipment configuration)
A refrigeration system 100 according to Embodiment 1 includes a refrigerant circuit in which a compressor 1, a condenser 2, a flow path switching unit, a heat exchanger 11 for dehumidification, an expansion valve 9, and a cooler 10 are connected by a refrigerant pipe. It has. Moreover, the outdoor unit 30a, the dehumidification unit 40a, and the cooling unit 50a are provided, and the outdoor unit 30a and the cooling unit 50a are connected by refrigerant piping via the dehumidification unit 40a.

The outdoor unit 30a has a compressor 1 and a condenser 2, which are connected by a refrigerant pipe. The dehumidifying unit 40a has a dehumidifying heat exchanger 11 and a flow path switching means. In the first embodiment, the flow path switching means is a plurality of solenoid valves, and the first solenoid valve 3, the second solenoid valve 4, the third solenoid valve 5, the fourth solenoid valve 6, the fifth solenoid valve 7, And it comprises the sixth solenoid valve 8.

The dehumidifying heat exchanger 11 is composed of, for example, a refrigerant pipe and a metal plate. The refrigerant pipe and the metal plate are joined, for example, by welding or pressure bonding (caulking). When the refrigerant flows through the refrigerant pipe of the dehumidifying heat exchanger 11, the refrigerant and air exchange heat, the refrigerant is cooled or heated, and the dehumidifying heat exchanger 11 itself is also cooled or heated. In the dehumidifying heat exchanger 11, the cooling surface is oriented vertically, that is, the cooling surface is oriented in the vertical direction, and frost or water droplets adhering to the cooling surface are likely to fall.

Further, below the dehumidifying heat exchanger 11, there is provided a frost receiver 13 for receiving frost or water droplets dropped from the dehumidifying heat exchanger 11. The frost receiver 13 is a container for storing frost or water droplets. The frost receiver 13 is provided, for example, in a position where the inside of the dehumidifying unit 40a can be easily attached and detached. The frost acceptor 13 may be provided outside the dehumidifying unit 40a, and the frost acceptor 13 is provided outside the dehumidifying unit 40a. It becomes easy to carry out of the freezer warehouse.

In the refrigeration system 100 according to the first embodiment, for example, after the defrosting of the dehumidifying heat exchanger 11 is completed, the notification means 16 (see FIG. 2 to be described later) by sound or display or the like is used. The fact that the defrost has been completed is notified. When the notification means 16 notifies that the defrosting of the dehumidifying heat exchanger 11 has been completed, the worker who has received the notification carries out the frost or water accumulated in the frost receiver 13 to the outside of the freezer warehouse. . The notification unit 16 is, for example, a buzzer, a speaker, an LED, a display screen, or the like.

With the above configuration, drain piping work, heaters for preventing pipe freezing, and heat insulating material processing, which were conventionally required, are no longer necessary, and construction efficiency can be realized.

In addition, about the heat exchanger 11 for dehumidification, the thing using a fin tube is also assumed. In that case, by forming the fin pitch wider than the cooler 10, it is possible to increase the amount of frost formed on the dehumidifying heat exchanger 11, and to defrost the dehumidifying heat exchanger 11 in a short time. Can be executed.

One end of the dehumidifying heat exchanger 11 is connected to one end of the first electromagnetic valve 3 and one end of the second electromagnetic valve 4 through refrigerant pipes, and the other end of the dehumidifying heat exchanger 11 is connected to the third electromagnetic valve. 5 and one end of the fourth electromagnetic valve 6 are connected to each other by refrigerant piping.

One end of the fifth solenoid valve 7 is connected to the other end of the first solenoid valve 3 by a refrigerant pipe, and the other end of the fifth solenoid valve 7 is connected to the other end of the third solenoid valve 5 by a refrigerant pipe. ing. One end of the sixth solenoid valve 8 is connected to the other end of the second solenoid valve 4 by a refrigerant pipe, and the other end of the fourth solenoid valve 6 is connected to the other end of the fourth solenoid valve 6 by a refrigerant pipe. ing. The cooling unit 50a has an expansion valve 9 and a cooler 10, which are connected by a refrigerant pipe.

A condenser 2, a first electromagnetic valve 3 and a fifth electromagnetic valve 7 are connected between the outdoor unit 30a and the dehumidifying unit 40a, and the suction side of the compressor 1 and the second electromagnetic valve 4 are connected. And the 6th solenoid valve 8 is connected. Further, the third electromagnetic valve 5, the fifth electromagnetic valve 7 and the expansion valve 9 are connected between the dehumidifying unit 40a and the cooling unit 50a, and further, the cooler 10, the fourth electromagnetic valve 6 and A sixth electromagnetic valve 8 is connected.

FIG. 2 is a functional block diagram of the control device 60a of the refrigeration system 100 according to Embodiment 1 of the present invention.
The refrigeration system 100 according to the first embodiment is provided inside and outside the control device 60a, a sensor 70 that detects the temperature of the dehumidifying heat exchanger 11, a remote controller 71 that remotely controls the refrigeration system 100, and the control device 60a. And a switch 72 for operating the refrigeration system 100.

The control device 60a has a normal mode, a dehumidification mode, and a defrost mode, and controls the flow path switching means and the like according to each mode. The control device 60 a includes a defrost determination unit 61, a dehumidification determination unit 62, a capability determination unit 63, and an operation control unit 64.

The defrost determination unit 61 acquires information from the sensor 70, the remote controller 71, the switch 72, and the like during operation, and determines whether or not the dehumidification heat exchanger 11 is necessary. In addition, as a method for determining whether or not the defrosting heat exchanger 11 needs to be defrosted, any method may be adopted as long as it can detect the frosting state of the dehumidifying heat exchanger 11.

For example, if the temperature of the dehumidifying heat exchanger 11 detected by the sensor 70 is equal to or lower than a preset threshold value, the defrost determining means 61 is frosted and the dehumidifying heat exchanger 11 It may be determined that defrosting is necessary. Further, when there is a defrost command from the remote controller 71 or the switch 72, the defrost determination means 61 determines that the dehumidifying heat exchanger 11 is frosted and the dehumidifying heat exchanger 11 needs to be defrosted. Also good. In addition, a well-known technique can be used about the determination method of the necessity of defrost of the heat exchanger 11 for dehumidification.

The dehumidification determining means 62 acquires information from the sensor 70, the remote controller 71, the switch 72, etc. during operation, and determines whether or not dehumidification is necessary in the freezer warehouse. As a method for determining whether or not the defrosting is necessary in the freezer warehouse, any method may be adopted as long as the humidity in the freezer warehouse can be detected.

For example, the dehumidification determination means 62 may determine that dehumidification in the freezer warehouse is necessary if the temperature of the dehumidification heat exchanger 11 detected by the sensor 70 is equal to or higher than a preset threshold. Further, the dehumidification determining means 62 may determine that dehumidification in the refrigeration warehouse is necessary when there is a dehumidification command from the remote controller 71 or the switch 72. In addition, a well-known technique can be used about the determination method of the necessity for defrosting in a freezer warehouse.

The capability determination unit 63 determines whether the capability condition and the capability limit condition are satisfied based on the information acquired from the sensor 70. Here, the capacity condition is a condition in which the condensation capacity of the outdoor unit 30a exceeds the required evaporation capacity of the cooling unit 50a.

The operation control means 64 performs main operation control of the dehumidifying unit 40a and the cooling unit 50a. Specifically, the flow path switching means, the notifying means 16 and the expansion valve 9 are controlled in accordance with the determination results of the respective modes or the defrost determination means 61, the dehumidification determination means 62, and the capacity determination means 63. To do. Further, the operation control means 64 acquires and holds operation information, which is information indicating, for example, cooling operation of the cooling unit 50a, cooling stop, and the like through communication with the outdoor unit 30a.

(Operation)
FIG. 3 is a diagram showing a control flow at the time of operation of the refrigeration system 100 according to Embodiment 1 of the present invention, and FIG. 4 is a refrigerant in the normal mode of the refrigeration system 100 according to Embodiment 1 of the present invention. 5 is a diagram illustrating an example of the flow of refrigerant, FIG. 5 is a diagram illustrating an example of the flow of refrigerant in the dehumidification mode of the refrigeration system 100 according to Embodiment 1 of the present invention, and FIG. 6 is a diagram illustrating the implementation of the present invention. It is a figure which shows an example of the flow of the refrigerant | coolant at the time of the defrost mode of the refrigerating system 100 which concerns on the form 1. The arrows in FIGS. 4 to 6 indicate the flow of the refrigerant.

Hereinafter, the control flow of the refrigeration system 100 according to the first embodiment will be described with reference to FIGS.
After turning on the power (step S101), the operation control means 64 is configured so that the condenser 2 and the expansion valve 9 communicate with each other and the cooler 10 and the suction side of the compressor 1 communicate with each other as shown in FIG. Open and close each solenoid valve. Specifically, the operation control means 64 closes the first solenoid valve 3, the second solenoid valve 4, the third solenoid valve 5, and the fourth solenoid valve 6, and the fifth solenoid valve 7, The sixth solenoid valve 8 is opened (step S102). As described above, the refrigerant flow path in the dehumidifying unit 40a is changed to a flow path in which the refrigerant from the outdoor unit 30a flows to the cooling unit 50a without passing through the heat exchanger 11 for dehumidification. It becomes composition.

After step S102, the dehumidification determining means 62 determines whether dehumidification in the freezer warehouse is necessary (step S103). If it is determined that dehumidification in the refrigerated warehouse is not necessary (No in step S103), the dehumidification determining unit 62 executes step S103 again. On the other hand, when the dehumidification determining unit 62 determines that dehumidification in the refrigerated warehouse is necessary (Yes in step S103), the process proceeds to step S104.

In step S104, as shown in FIG. 5, the operation control means 64 causes the cooler 10 and the dehumidifying heat exchanger 11 to communicate with each other, and the dehumidifying heat exchanger 11 and the suction side of the compressor 1 to communicate with each other. In addition, each solenoid valve is opened and closed. Specifically, the operation control means 64 closes the first solenoid valve 3, the third solenoid valve 5, and the sixth solenoid valve 8, the second solenoid valve 4, the fourth solenoid valve 6, The fifth solenoid valve 7 is opened. In this way, the refrigerant flow path in the dehumidifying unit 40a is made a flow path in which the refrigerant from the cooling unit 50a flows to the outdoor unit 30a via the heat exchanger 11 for dehumidification, so that the refrigerant circuit configuration in the dehumidifying mode is achieved. It becomes. With this refrigerant circuit configuration, the cold refrigerant after passing through the cooler 10 passes through the dehumidification heat exchanger 11 and is cooled to promote frost formation on the dehumidification heat exchanger 11, thereby realizing dehumidification in the refrigeration warehouse. To do.

After step S104, the dehumidification determining means 62 determines whether the dehumidification in the freezer warehouse has been completed (step S105). If it is determined that the dehumidification in the refrigerated warehouse has been completed (Yes in step S105), the dehumidification determining means 62 returns to step S102. On the other hand, when the dehumidification determining unit 62 determines that the dehumidification in the freezer warehouse is not completed (No in step S105), the process proceeds to step S106.

In step S106, the defrost determination means 61 determines whether or not the dehumidification heat exchanger 11 needs to be defrosted. If it is determined that the defrosting of the dehumidifying heat exchanger 11 is not necessary (No in step S106), the defrost determining means 61 returns to step S105. On the other hand, when the defrost determination means 61 determines that the defrost of the dehumidifying heat exchanger 11 is necessary (Yes in step S106), the process proceeds to step S107.

In step S107, as shown in FIG. 6, the operation control means 64 communicates each electromagnetic so that the condenser 2 and the dehumidifying heat exchanger 11 communicate with each other, and the dehumidifying heat exchanger 11 and the expansion valve 9 communicate with each other. Open and close the valve. Specifically, the operation control means 64 closes the second solenoid valve 4, the fourth solenoid valve 6, and the fifth solenoid valve 7, the first solenoid valve 3, the third solenoid valve 5, The sixth solenoid valve 8 is opened. Thus, the refrigerant circuit configuration in the defrost mode is achieved by using the refrigerant flow path in the dehumidifying unit 40a as a flow path in which the refrigerant from the outdoor unit 30a flows to the cooling unit 50a through the dehumidifying heat exchanger 11. It becomes. With this refrigerant circuit configuration, the warm refrigerant after passing through the condenser 2 passes through the dehumidifying heat exchanger 11 and is heated, whereby defrosting of the dehumidifying heat exchanger 11 is realized.

The defrost of the dehumidifying heat exchanger 11 causes frost or water droplets or the like adhering to the cooling surface of the dehumidifying heat exchanger 11 to fall. The dropped frost or water droplets are below the dehumidifying heat exchanger 11. It accommodates in the frost receiver 13 provided in the.

After step S107, the defrost determination means 61 determines whether the defrost of the dehumidifying heat exchanger 11 is completed (step S108). If it is determined that the defrosting of the dehumidifying heat exchanger 11 has not been completed (No in step S108), the defrost determination unit 61 executes step S108 again. On the other hand, when the defrost determination means 61 determines that the defrost of the dehumidifying heat exchanger 11 is completed (Yes in step S108), the operation control means 64 completes the defrosting of the dehumidifying heat exchanger 11 by the notification means 16. It is notified (step S109) and it returns to step S102.

In addition, the worker who received the notification carries out the frost or water accumulated in the frost receiver 13 to the outside of the freezer warehouse. Further, the notification that the defrosting of the dehumidifying heat exchanger 11 has been completed is stopped by the worker who has received the notification. Further, the notification that the defrosting of the dehumidifying heat exchanger 11 has been completed may be omitted, and an operator who performs periodic inspection may carry out frost or water accumulated in the frost receiver 13 to the outside of the freezer warehouse. It may be.

Further, the operation control unit 64 changes the opening degree of the expansion valve 9 according to the determination result of the capability determination unit 63.

As described above, in the refrigeration system 100 according to the first embodiment, the compressor 1, the condenser 2, the flow path switching unit, the dehumidifying heat exchanger 11, the expansion valve 9, and the cooler 10 are connected by piping. A refrigerant circuit, and the flow path switching means includes at least a first flow path in which the refrigerant condensed in the condenser 2 flows to the cooler 10 via the heat exchanger 11 for dehumidification, and cooling. The second flow path in which the refrigerant evaporated in the condenser 10 flows to the compressor 1 through the dehumidification heat exchanger 11, and the cooler in which the refrigerant condensed in the condenser 2 does not go through the dehumidification heat exchanger 11 10 is switched to any one of the third flow paths that flow to 10.

The refrigeration system 100 according to the first embodiment controls the refrigerant flowing to the dehumidification heat exchanger 11 by opening and closing each solenoid valve that is a flow path switching unit, thereby dehumidifying and dehumidifying the dehumidification heat exchanger 11. Defrosting of the heat exchanger 11 is realized. Therefore, according to the refrigeration system 100 according to the first embodiment, it is possible to improve the operation efficiency without exhausting the humidified air to the outside.

Further, the refrigeration system 100 according to the first embodiment includes an outdoor unit 30a having the compressor 1 and the condenser 2, a cooling unit 50a having the cooler 10 and the expansion valve 9, and a heat exchanger 11 for dehumidification. And a dehumidifying unit 40a having a flow path switching means, and the outdoor unit 30a and the cooling unit 50a are connected by piping via the dehumidifying unit 40a.

In the refrigeration system 100 according to the first embodiment, the dehumidifying unit 40a is unitized. Therefore, the dehumidifying function can be added to the existing refrigeration apparatus only by adding the dehumidifying unit 40a to the existing refrigeration apparatus.

Further, by arranging the dehumidifying unit 40a in the vicinity of the cooling unit 50a, an effect of reducing the frosting frequency on the cooler 10 can be obtained. Alternatively, by arranging the dehumidifying unit 40a in the vicinity of the entrance / exit of the refrigerated warehouse where outside air easily enters, an effect of positively dehumidifying the inside of the refrigerated warehouse can be obtained.

Embodiment 2. FIG.
Hereinafter, Embodiment 2 of the present invention will be described, but the description overlapping with Embodiment 1 will be omitted, and the same reference numerals will be given to the same or corresponding parts as those in Embodiment 1.

FIG. 7 is a schematic diagram illustrating the configuration of the refrigeration system 100a according to Embodiment 2 of the present invention.
Hereinafter, the configuration of the refrigeration system 100a according to the second embodiment will be described with reference to FIG. In the second embodiment, an example in which the refrigeration system 100a is applied to a refrigeration warehouse will be described.

(Equipment configuration)
The refrigeration system 100a according to Embodiment 2 includes a compressor 1, a condenser 2, a flow path switching unit, a dehumidifying heat exchanger 11, a first expansion valve 9a, a cooler 10, and a second expansion valve 12. A refrigerant circuit connected by a refrigerant pipe is provided. Moreover, the outdoor unit 30a, the dehumidification unit 40a, and the cooling unit 50a are provided, and the outdoor unit 30a and the cooling unit 50a are connected by refrigerant piping via the dehumidification unit 40a.

The outdoor unit 30a has a compressor 1 and a condenser 2, which are connected by a refrigerant pipe. The dehumidifying unit 40a has a dehumidifying heat exchanger 11 and a flow path switching means. In the second embodiment, the flow path switching means is a plurality of flow path switching valves, and includes a first flow path switching valve 14 and a second flow path switching valve 15.

One end of the dehumidifying heat exchanger 11 is connected to the second flow path switching valve 15 and a refrigerant pipe, and the other end of the dehumidifying heat exchanger 11 is connected to the first expansion valve 9a of the cooling unit 50a and the refrigerant pipe. It is connected. The first flow path switching valve 14 and the second flow path switching valve 15 are connected by a refrigerant pipe. The cooling unit 50a includes a first expansion valve 9a, a cooler 10, and a second expansion valve 12, and the first expansion valve 9a, the cooler 10, and the second expansion valve 12 are sequentially connected by a refrigerant pipe.

The condenser 2 and the first flow path switching valve 14 are connected between the outdoor unit 30a and the dehumidifying unit 40a, and the suction side of the compressor 1 and the second flow path switching valve 15 are further connected. Yes. Further, the dehumidifying heat exchanger 11 and the first expansion valve 9a are connected between the dehumidifying unit 40a and the cooling unit 50a, and further, the second expansion valve 12 and the first flow path switching valve 14 are connected. Has been.

In the second embodiment, since the refrigerant is controlled by the flow path switching unit, the direction of the refrigerant passing through the cooler 10 is changed according to each mode of the refrigeration system 100a. Therefore, by providing the second expansion valve 12 between the first flow path switching valve 14 and the cooler 10 as shown in FIG.

Although the refrigeration system 100a according to the second embodiment includes the control device 60a, the functional blocks of the control device 60a are the same as those in FIG.

(Operation)
FIG. 8 is a diagram showing a control flow during operation of the refrigeration system 100a according to Embodiment 2 of the present invention, and FIG. 9 shows refrigerant in the dehumidifying mode of the refrigeration system 100a according to Embodiment 2 of the present invention. FIG. 10 is a diagram illustrating an example of the refrigerant flow when the refrigeration system 100a according to Embodiment 2 of the present invention is in the defrost mode. Note that the arrows in FIGS. 9 and 10 indicate the flow of the refrigerant.

Hereinafter, the control flow of the refrigeration system 100a according to the second embodiment will be described with reference to FIGS.
After the power is turned on (step S201), the operation control means 64 switches the first flow path switching valve 14 so that the condenser 2 and the second expansion valve 12 communicate with each other as shown in FIG. Further, the operation control means 64 switches the second flow path switching valve 15 so that the suction side of the compressor 1 and the dehumidifying heat exchanger 11 communicate with each other. Then, both the first expansion valve 9a and the second expansion valve 12 are throttled (step S202).

In this way, the refrigerant flow path in the dehumidifying unit 40a is made a flow path in which the refrigerant from the cooling unit 50a flows to the outdoor unit 30a via the heat exchanger 11 for dehumidification, so that the refrigerant circuit configuration in the dehumidifying mode is achieved. It becomes. With this refrigerant circuit configuration, after the cold refrigerant that has passed through the cooler 10 is further cooled by being depressurized by the first expansion valve 9a, it passes through the heat exchanger 11 for dehumidification, and is then cooled by passing through the heat exchanger 11 for dehumidification. It promotes frost formation on the exchanger 11 and realizes dehumidification in the freezer warehouse. As described above, the first expansion valve 9a plays a role of adjusting the evaporation temperature of the refrigerant in the dehumidifying mode.

After step S202, the dehumidification determining means 62 determines whether the dehumidification in the freezer warehouse has been completed (step S203). When it is determined that the dehumidification in the refrigeration warehouse has been completed (Yes in step S203), the dehumidification determining unit 62 returns to step S202. On the other hand, when the dehumidification determining unit 62 determines that the dehumidification in the freezer warehouse has not been completed (No in step S203), the process proceeds to step S204.

In step S204, the defrost determination means 61 determines whether the defrost of the dehumidifying heat exchanger 11 is necessary. If it is determined that the defrosting of the dehumidifying heat exchanger 11 is not necessary (No in step S204), the defrost determination unit 61 returns to step S203. On the other hand, when the defrost determination means 61 determines that the defrost of the dehumidifying heat exchanger 11 is necessary (Yes in step S204), the process proceeds to step S205.

In step S205, as shown in FIG. 10, the operation control means 64 causes the condenser 2 and the second flow path switching valve 15, and the second expansion valve 12 and the second flow path switching valve 15 to communicate with each other. The first flow path switching valve 14 is switched. Further, the operation control means 64 includes the dehumidifying heat exchanger 11 and the first flow path switching valve 14, and the second flow path switching valve 15 so that the suction side of the compressor 1 and the first flow path switching valve 14 communicate with each other. Switch. Then, the first expansion valve 9a is throttled and the second expansion valve 12 is fully opened.

That is, the operation control means 64 is configured so that the condenser 2 and the dehumidifying heat exchanger 11 communicate with each other, and the second expansion valve 12 and the suction side of the compressor 1 communicate with each other. Each of the two flow path switching valves 15 is switched.

Thus, the refrigerant circuit configuration in the defrost mode is achieved by using the refrigerant flow path in the dehumidifying unit 40a as a flow path in which the refrigerant from the outdoor unit 30a flows to the cooling unit 50a through the dehumidifying heat exchanger 11. It becomes. With this refrigerant circuit configuration, the warm refrigerant after passing through the condenser 2 passes through the dehumidifying heat exchanger 11 and is heated, whereby defrosting of the dehumidifying heat exchanger 11 is realized. By reducing the pressure of the warm refrigerant that has passed through the dehumidifying heat exchanger 11 with the first expansion valve 9a, it is possible to cause the cold refrigerant to flow through the cooler 10. The refrigerant that has passed through the cooler 10 returns to the compressor 1 without being depressurized by the second expansion valve 12.

After step S205, the defrost determining means 61 determines whether or not the defrosting of the dehumidifying heat exchanger 11 is completed (step S206). If it is determined that the defrosting of the dehumidifying heat exchanger 11 has not been completed (No in step S206), the defrost determination unit 61 executes step S206 again. On the other hand, when the defrost determination means 61 determines that the defrost of the dehumidifying heat exchanger 11 is completed (Yes in step S206), the operation control means 64 completes the defrosting of the dehumidifying heat exchanger 11 by the notification means 16. It is notified (step S207) and it returns to step S202.

The operation control means 64 changes the opening degrees of the first expansion valve 9a and the second expansion valve 12 according to the determination result of the capacity determination means 63.

Further, in the second embodiment, the control device 60a has only the dehumidification mode and the defrost mode, and the flow path of the refrigerant in the dehumidification unit 40a from the outdoor unit 30a as in the first embodiment. There is no normal mode in which the refrigerant flows into the cooling unit 50a without going through the dehumidifying heat exchanger 11.

As described above, in the refrigeration system 100a according to the second embodiment, the compressor 1, the condenser 2, the flow path switching unit, the heat exchanger 11 for dehumidification, the first expansion valve 9a, and the cooler 10 are refrigerants. A refrigerant circuit connected by piping is provided, and the flow path switching means is a first flow path in which at least the refrigerant condensed by the condenser 2 flows to the cooler 10 via the heat exchanger 11 for dehumidification. And the refrigerant | coolant evaporated by the cooler 10 switches to either the 2nd flow path which flows into the compressor 1 via the heat exchanger 11 for dehumidification.

The refrigeration system 100a according to the second embodiment controls the refrigerant flowing into the dehumidification heat exchanger 11 by switching each flow path switching valve, which is a flow path switching unit, so that dehumidification and dehumidification by the dehumidification heat exchanger 11 are performed. Defrosting of the heat exchanger 11 for dehumidification is realized. Therefore, according to the refrigeration system 100a according to the second embodiment, it is possible to improve the operation efficiency without exhausting the humidified air outside the room.

Further, the refrigeration system 100a according to the second embodiment includes an outdoor unit 30a having the compressor 1 and the condenser 2, a cooling unit 50a having the cooler 10 and the first expansion valve 9a, and heat exchange for dehumidification. The outdoor unit 30a and the cooling unit 50a are connected to each other by a refrigerant pipe via the dehumidification unit 40a.

In the refrigeration system 100a according to the second embodiment, the dehumidifying unit 40a is unitized as in the first embodiment. Therefore, the dehumidifying function can be added to the existing refrigeration apparatus only by adding the dehumidifying unit 40a to the existing refrigeration apparatus.

In addition, the refrigeration system 100a according to Embodiment 2 includes two expansion valves, the first expansion valve 9a is connected to one end of the cooler 10, and the second expansion valve 12 is connected to the cooler 10. And the other end of the pipe. Therefore, the second expansion valve 12 plays a role of adjusting the evaporation temperature of the refrigerant in the dehumidifying mode, and can be positively frosted on the dehumidifying heat exchanger 11 by the second expansion valve 12.

Further, similarly to the first embodiment, by arranging the dehumidifying unit 40a in the vicinity of the cooling unit 50a, an effect of reducing the frequency of frost formation on the cooler 10 can be obtained. Alternatively, by arranging the dehumidifying unit 40a in the vicinity of the entrance / exit of the refrigerated warehouse where outside air easily enters, an effect of positively dehumidifying the inside of the refrigerated warehouse can be obtained.

In the first embodiment, the fourth electromagnetic valve 6 may be changed to an expansion valve. By doing so, the expansion valve, in the dehumidifying mode, plays a role of adjusting the evaporation temperature of the refrigerant, like the first expansion valve 9a in the second embodiment, and therefore the expansion valve is used for dehumidification. The heat exchanger 11 can be actively frosted.

Further, the second expansion valve 12 in the second embodiment may be provided in the refrigeration system 100a according to the first embodiment. The position where the second expansion valve 12 is provided is between the cooler 10 and the dehumidifying unit 40a, as in the second embodiment. By doing so, the second expansion valve 12 plays a role of adjusting the evaporation temperature of the refrigerant, like the first expansion valve 9a in the second embodiment, in the dehumidifying mode. 12, the dehumidifying heat exchanger 11 can be actively frosted.

1 compressor, 2 condenser, 3rd solenoid valve, 4th solenoid valve, 5th solenoid valve, 6th 4th solenoid valve, 7th 5th solenoid valve, 8th 6th solenoid valve, 9th expansion valve, 9ath 1 expansion valve, 10 cooler, 11 heat exchanger for dehumidification, 12 second expansion valve, 13 frost acceptor, 14 first flow path switching valve, 15 second flow path switching valve, 16 notification means, 30a outdoor unit, 40a Dehumidification unit, 50a cooling unit, 60a control device, 61 defrost determination means, 62 dehumidification determination means, 63 capacity determination means, 64 operation control means, 70 sensor, 71 remote control, 72 switch, 100 refrigeration system, 100a refrigeration system.

Claims

A compressor, a condenser, a flow path switching means, a heat exchanger for dehumidification, an expansion valve, and a refrigerant circuit connected to a cooler by piping;
The flow path switching means has at least a refrigerant flow path,
A first flow path through which the refrigerant condensed in the condenser flows to the cooler via the dehumidifying heat exchanger, and the refrigerant evaporated in the cooler via the dehumidifying heat exchanger A refrigeration system that is switched to one of the second flow paths that flow through.
An outdoor unit having the compressor and the condenser;
A cooling unit having the cooler and the expansion valve;
A dehumidifying unit having the dehumidifying heat exchanger and the flow path switching means,
The refrigeration system according to claim 1, wherein the outdoor unit and the cooling unit are connected to each other through the dehumidifying unit.
The flow path switching means is configured such that the refrigerant condensed in the first flow path, the second flow path, and the condenser flows to the cooler without passing through the heat exchanger for dehumidification. The refrigeration system according to claim 1 or 2, wherein the refrigeration system is switched to one of the third flow paths.
The flow path switching means is composed of a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, and a sixth solenoid valve,
One end of the dehumidifying heat exchanger is connected to one end of the first electromagnetic valve and one end of the second electromagnetic valve, and the other end of the dehumidifying heat exchanger is connected to the third electromagnetic valve. One end and one end of the fourth solenoid valve are connected to each other, one end of the fifth solenoid valve is connected to the other end of the first solenoid valve, and the other end of the fifth solenoid valve is connected to the other end. A pipe is connected to the third solenoid valve, one end of the sixth solenoid valve is connected to the other end of the second solenoid valve, and the other end of the sixth solenoid valve is connected to the other of the fourth solenoid valve. The refrigeration system according to claim 3, wherein the refrigeration system is pipe-connected to the end.
The refrigeration system according to any one of claims 1 to 4, further comprising a control device that has a dehumidification mode and a defrost mode, and controls the flow path switching unit according to each mode.
The control device includes:
During the dehumidifying mode,
The flow switching means is controlled so that the cooler and the dehumidifying heat exchanger communicate with each other, and the dehumidifying heat exchanger and the suction side of the compressor communicate with each other, The refrigeration system according to claim 5, wherein the refrigerant evaporated in the cooler is switched to a flow path that flows to the compressor via the dehumidifying heat exchanger.
The control device includes:
In the defrost mode,
The flow path switching means is controlled so that the condenser and the dehumidifying heat exchanger communicate with each other, and the dehumidifying heat exchanger and the expansion valve communicate with each other. The refrigeration system according to claim 5 or 6, wherein the condensed refrigerant is switched to a flow path that flows to the cooler via the dehumidifying heat exchanger.
The control device includes:
In addition to the dehumidification mode and the defrost mode, it has a normal mode,
During the normal mode,
The flow path switching means is controlled so that the condenser and the expansion valve communicate with each other, and the cooler and the suction side of the compressor communicate with each other, and the refrigerant flow path is condensed by the condenser. The refrigeration system according to any one of claims 5 to 7, wherein the refrigerant is switched to a flow path that flows to the cooler without passing through the dehumidifying heat exchanger.
The flow path switching means is composed of a first flow path switching valve and a second flow path switching valve,
One end of the dehumidifying heat exchanger is connected to the second flow path switching valve by piping, and the other end of the dehumidifying heat exchanger is connected to the expansion valve by refrigerant piping, and the first flow The refrigeration system according to any one of claims 1, 2, and 5 to 7, wherein the path switching valve and the second channel switching valve are connected by piping.
Two expansion valves are provided,
One of the expansion valves is connected to one end of the cooler by piping,
The refrigeration system according to any one of claims 1 to 9, wherein the other expansion valve is connected to the other end of the cooler by piping.