JPWO2017130299A1 - Refrigeration equipment - Google Patents

Abstract

A refrigeration apparatus capable of performing defrosting of an evaporator in a short time is obtained. The refrigeration apparatus (100) includes a refrigerant circuit (100A) that connects the compressor (10), the condenser (12), the expansion device (24), and the evaporator (26) with refrigerant piping, and circulates the refrigerant. When performing a defrosting operation for defrosting the evaporator, it has a flow path switching device (28) that forms a flow path for allowing the refrigerant compressed by the compressor to flow into the evaporator, and there are two or more evaporators. Are connected in parallel, and when performing the defrosting operation, the first defrosting operation is performed in which the refrigerant compressed by the compressor flows into all the evaporators, and then compressed into one or more evaporators. The second defrosting operation is performed in which the refrigerant compressed by the compressor is allowed to flow and the refrigerant compressed by the compressor is not allowed to flow into the other evaporators.

Description

  The present invention relates to a refrigeration apparatus that performs a defrosting operation.

  Conventionally, a refrigerating apparatus that performs a defrosting operation is known (see, for example, Patent Document 1). In the conventional refrigeration apparatus described in Patent Document 1, defrosting of a plurality of evaporators is performed simultaneously by flowing hot gas through the plurality of evaporators simultaneously.

JP 2009-287789 A

  However, in the conventional refrigeration apparatus described in Patent Document 1, since a plurality of evaporators are defrosted simultaneously, it takes a long time to defrost the evaporators.

  The present invention has been made against the background of the above problems, and an object thereof is to obtain a refrigeration apparatus capable of performing defrosting of an evaporator in a short time.

  The refrigeration apparatus according to the present invention includes a refrigerant circuit that connects a compressor, a condenser, an expansion device, and an evaporator with refrigerant piping and circulates the refrigerant, and performs a defrosting operation for defrosting the evaporator. And a flow path switching device that forms a flow path for allowing the refrigerant compressed by the compressor to flow into the evaporator, wherein two or more of the evaporators are connected in parallel, and the defrosting operation is performed. When performing, the 1st defrost operation which makes the refrigerant | coolant compressed with the said compressor flow in into all the said evaporators is performed, and the refrigerant | coolant compressed with the said compressor flows into one or more said evaporators after that And a second defrosting operation is performed in which the refrigerant compressed by the compressor does not flow into the other evaporator.

  According to the refrigeration apparatus of the present invention, the pressure of the refrigerant discharged from the compressor is quickly increased in the first defrosting operation, and the evaporator is selectively defrosted in the second defrosting operation thereafter. Thus, the evaporator can be defrosted in a short time.

It is the figure which described typically an example of the structure of the freezing apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining an example of operation | movement of the freezing apparatus described in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is omitted or simplified as appropriate. In addition, the shape, size, arrangement, and the like of the configuration described in each drawing can be changed as appropriate within the scope of the present invention.

Embodiment 1 FIG.
[Refrigeration equipment]
FIG. 1 is a diagram schematically illustrating an example of the configuration of the refrigeration apparatus according to Embodiment 1 of the present invention. In FIG. 1, the refrigerant circuit 100A is indicated by a solid line, and the bypass passage 100B is indicated by a broken line. A refrigeration apparatus 100 shown in FIG. 1 cools the interior of a room and is applied to, for example, a large refrigeration warehouse. The refrigeration apparatus 100 includes an outdoor unit 1 and a plurality of indoor units 2 connected in parallel with the outdoor unit 1. In FIG. 1, the refrigeration apparatus 100 having two indoor units 2 including the first indoor unit 2a and the second indoor unit 2b is illustrated, but the refrigeration apparatus 100 includes three or more units connected in parallel to each other. The indoor unit 2 may be included. In the following description, in order to facilitate understanding of this embodiment, when there is no need to distinguish or specify the first indoor unit 2a and the second indoor unit 2b, they are simply referred to as the indoor unit 2. There are cases where explanations are given. Similarly, the constituent elements of the first indoor unit 2a and the second indoor unit 2b may be omitted or simplified when there is no need to particularly distinguish or specify them. That is, the first control device 20a and the second control device 20b will be described simply as the control device 20, the first switch device 22a and the second switch device 22b will be described simply as the switch device 22, and the first expansion device 24a and The second expansion device 24b is simply described as the expansion device 24, the first evaporator 26a and the second evaporator 26b are simply described as the evaporator 26, and the first flow path switching device 28a and the second flow path switching device are described. 28b may be simply described as the flow path switching device 28.

[Outdoor unit]
The outdoor unit 1 is installed outside the room and functions as a heat source machine. The outdoor unit 1 has a compressor 10 and a condenser 12 connected by refrigerant piping. The compressor 10 sucks and compresses refrigerant and discharges it in a high-temperature and high-pressure state. The compressor 10 is an inverter compressor that is controlled by an inverter, for example, and can change the capacity (the amount of refrigerant sent out per unit time) by arbitrarily changing the operating frequency. The condenser 12 condenses the refrigerant by exchanging heat between the refrigerant and air, for example. The outdoor unit 1 also has a control device 16 that controls the outdoor unit 1. The control device 16 is configured to include hardware such as an analog circuit or a digital circuit, or software such as a program executed by an arithmetic device such as a microcomputer or a CPU.

[Indoor unit]
The indoor unit 2 is installed inside the room and cools the room. The plurality of indoor units 2 are installed in the same room, for example. The plurality of indoor units 2 may be installed in different rooms. Each of the plurality of indoor units 2 includes an opening / closing device 22, an expansion device 24, and an evaporator 26 connected by a refrigerant pipe. The opening / closing device 22 controls the circulation of the refrigerant by performing an opening / closing operation. The expansion device 24 expands the refrigerant. For example, the expansion device 24 is an electronic expansion valve that can adjust the opening degree, but may be a capillary tube that cannot adjust the opening degree. In the case where the expansion device 24 is an electronic expansion valve or the like that can adjust the opening degree, the opening / closing device 22 may be omitted. The evaporator 26 evaporates the refrigerant by exchanging heat between the refrigerant and air. The room is cooled by the endothermic effect when the refrigerant is evaporated. The indoor unit 2 has a control device 20 that controls the indoor unit 2. The control device 20 is configured to include hardware such as an analog circuit or a digital circuit, or software such as a program executed by an arithmetic device such as a microcomputer or a CPU. In the example of FIG. 1, the first indoor unit 2a has the first control device 20a, the second indoor unit 2b has the second control device 20b, the first control device 20a, the second control device 20b, Controls the first indoor unit 2a and the second indoor unit 2b while performing communication, but the first control device 20a and the second control device 20b may be integrally formed. Moreover, the 1st control apparatus 20a, the 2nd control apparatus 20b, and the control apparatus 16 of the outdoor unit 1 may be integrally formed.

[Refrigerant circuit]
A refrigerant circuit 100A is formed by connecting the outdoor unit 1 and the indoor unit 2 with a refrigerant pipe. As the refrigerant circulates through the refrigerant circuit 100A in the order of the compressor 10, the condenser 12, the expansion device 24, and the evaporator 26, the room in which the evaporator 26 is installed is cooled.

[Bypass path]
Moreover, the refrigeration apparatus 100 of the example of this embodiment has a bypass 100B connected to the refrigerant circuit 100A. The bypass 100B branches from between the discharge side of the compressor 10 and the condenser 12, and allows the high-temperature and high-pressure refrigerant compressed by the compressor 10 to flow into the evaporator 26. In the refrigeration apparatus 100 of the example of this embodiment, the bypass passage 100B connects between the compressor 10 and the condenser 12 and between the expansion device 24 and the evaporator 26. A decompression device 14 and a flow path switching device 28 are disposed in the bypass passage 100B.

  The decompression device 14 decompresses the pressure of the refrigerant flowing through the bypass passage 100B, and is accommodated in the outdoor unit 1, for example. The decompression device 14 is a needle valve, for example, but may be a capillary tube or the like. In the refrigeration apparatus 100 of the example of this embodiment, the pressure of the refrigerant flowing in the bypass passage 100B is reduced by the decompression device 14 and flows into the evaporator 26. Therefore, the evaporator 26 having low pressure resistance may be used. it can.

  The flow path switching device 28 controls the flow of the refrigerant to each of the plurality of evaporators 26 via the bypass path 100B, and is accommodated in the indoor unit 2, for example. If the flow path switching device 28 has a function of reducing the pressure of the refrigerant flowing into the evaporator 26, the pressure reducing device 14 may be omitted. In the example of FIG. 1, the first flow path switching device 28a controls the flow of the refrigerant to the first evaporator 26a, and the second flow path switching device 28b is the refrigerant flow to the second evaporator 26b. It controls distribution. The first flow path switching device 28a and the second flow path switching device 28b are, for example, on-off valves.

[Cooling operation]
Next, the cooling operation of the refrigeration apparatus 100 of the example of this embodiment will be described. When the refrigeration apparatus 100 performs the cooling operation, the first opening / closing device 22a and the second opening / closing device 22b are in the open state, and the first flow path switching device 28a and the second flow path switching device 28b are in the closed state. Yes.

  The high-temperature and high-pressure refrigerant compressed by the compressor 10 is condensed by the condenser 12 and flows out of the outdoor unit 1. The refrigerant that has flowed out of the outdoor unit 1 is branched into a refrigerant that flows into the first indoor unit 2a and a refrigerant that flows into the second indoor unit 2b. The refrigerant flowing into the first indoor unit 2a passes through the first opening / closing device 22a and is expanded by the first expansion device 24a. The refrigerant expanded by the first expansion device 24a evaporates by absorbing heat from the air while flowing through the first evaporator 26a. The refrigerant evaporated in the first evaporator 26a flows out from the first indoor unit 2a and merges with the refrigerant flowing out from the second indoor unit 2b. The merged refrigerant flows into the outdoor unit 1, is sucked into the compressor 10, and is compressed again. In addition, the refrigerant that flows out of the outdoor unit 1 and flows into the second indoor unit 2b passes through the second opening / closing device 22b and is expanded by the second expansion device 24b. The refrigerant expanded by the second expansion device 24b evaporates by absorbing heat from the air while flowing through the second evaporator 26b. The refrigerant evaporated in the second evaporator 26b flows out from the second indoor unit 2b and merges with the refrigerant flowing out from the first indoor unit 2a. The merged refrigerant flows into the outdoor unit 1, is sucked into the compressor 10, and is compressed again.

  By the way, when the refrigeration apparatus 100 performs the cooling operation, frost may adhere to the evaporator 26. If frost adheres to the evaporator 26, the heat exchange efficiency of the evaporator 26 will fall and the refrigerating capacity of the freezing apparatus 100 will fall. Therefore, the refrigeration apparatus 100 of the example of this embodiment operates as follows.

[Operation of refrigeration cycle equipment]
FIG. 2 is a diagram illustrating an example of the operation of the refrigeration apparatus illustrated in FIG. When the refrigeration apparatus 100 shown in FIG. 1 starts the cooling operation in step S02 of FIG. 2, for example, the first indoor unit 2a and the second indoor unit 2b cool the room.

  In step S04 of FIG. 2, for example, the control device 20 determines whether or not the defrosting operation condition of one or more indoor units 2 is satisfied. Whether or not the defrosting operation condition is satisfied is determined based on, for example, whether or not a preset time has been reached. In some cases, it is determined that the defrosting operation condition is satisfied when a preset set period is reached. Further, by determining whether or not frost has adhered to the evaporator 26 using the temperature of the evaporator 26 and the temperature of the room in which the evaporator 26 is installed, the defrosting operation condition is established. Sometimes it is judged. Further, when receiving an instruction from a user input to an input device (not shown) such as a switch, it may be determined that the defrosting operation condition is satisfied. When the defrosting operation conditions for all the indoor units 2 are not satisfied in step S04, the refrigeration apparatus 100 continues the cooling operation.

[Defrosting operation]
When the defrosting operation condition for one or more indoor units 2 is satisfied in step S04, the refrigeration apparatus 100 performs the defrosting operation as described below. That is, the refrigeration apparatus 100 of the example of this embodiment performs the first defrosting operation of step S08 in the defrosting operation, and then executes the second defrosting operation of step S10. Hereinafter, an example in which the defrosting operation condition of the first indoor unit 2a is satisfied and the defrosting operation condition of the second indoor unit 2b is not satisfied will be described. The operation when the defrosting operation condition of the second indoor unit 2b is satisfied and the defrosting operation condition of the first indoor unit 2a is not satisfied is the operation of the second indoor unit 2a when the defrosting operation condition of the first indoor unit 2a is satisfied. Since it is substantially the same as the operation when the defrosting operation condition of 2b is not satisfied, the description is omitted.

(First defrosting operation)
In step S06, the refrigeration apparatus 100 performs the first defrosting operation. In the first defrosting operation, the refrigerant compressed by the compressor 10 is caused to flow into all the evaporators 26. That is, in the example of FIG. 1, when the first defrosting operation is performed, the first opening / closing device 22a and the second opening / closing device 22b are in the closed state, and the first flow path switching device 28a and the second flow path The switching device 28b is in the open state, and the high-temperature and high-pressure refrigerant compressed by the compressor 10 flows through the bypass 100B to the first evaporator 26a and the second evaporator 26b. Specifically, the high-temperature and high-pressure refrigerant compressed by the compressor 10 is decompressed by the decompression device 14 and flows out of the outdoor unit 1. The refrigerant that has flowed out of the outdoor unit 1 is branched into a refrigerant that flows into the first indoor unit 2a and a refrigerant that flows into the second indoor unit 2b. The refrigerant flowing into the first indoor unit 2a passes through the first flow path switching device 28a and flows into the first evaporator 26a. The refrigerant flowing into the first evaporator 26a heats the first evaporator 26a and flows out from the first indoor unit 2a. The refrigerant flowing out from the first indoor unit 2a merges with the refrigerant flowing out from the second indoor unit 2b. The merged refrigerant flows into the outdoor unit 1, is sucked into the compressor 10, and is compressed again. The refrigerant that has flowed into the second indoor unit 2b passes through the second flow path switching device 28b and flows into the second evaporator 26b. The refrigerant flowing into the second evaporator 26b heats the second evaporator 26b and flows out from the second indoor unit 2b. The refrigerant that has flowed out of the second indoor unit 2b merges with the refrigerant that has flowed out of the first indoor unit 2a. The merged refrigerant flows into the outdoor unit 1, is sucked into the compressor 10, and is compressed again. Thus, by performing the 1st defrost operation which makes the refrigerant | coolant compressed with the compressor 10 flow into all the evaporators 26, the pressure of the refrigerant | coolant discharged from the compressor 10 rises rapidly. This is because the flow path resistance of the bypass path 100B is reduced by forming a flow path for allowing the refrigerant compressed by the compressor 10 to flow into all the evaporators 26. Furthermore, by forming a flow path for allowing the refrigerant compressed by the compressor 10 to flow into all the evaporators 26, the refrigerant does not stay in the evaporators 26, so that the amount of refrigerant circulating can be increased.

  In step S08, control device 20 determines whether or not the first defrosting operation has ended. Whether or not the first defrosting operation has ended is determined based on, for example, whether or not the pressure of the refrigerant discharged from the compressor 10 has reached a preset pressure. Whether or not the first defrosting operation has ended may be determined by whether or not the temperature of the refrigerant discharged from the compressor 10 has reached a preset temperature. Further, whether or not the first defrosting operation has been completed may be determined by whether or not the first defrosting operation execution time in which the first defrosting operation has been performed has reached a preset set time. is there. The time for which the first defrosting operation is executed is, for example, 5 to 6 minutes.

(Second defrosting operation)
If it is determined in step S08 that the first defrosting operation has been completed, the second defrosting operation is executed in step S10. In the second defrosting operation, the refrigerant compressed by the compressor 10 is not allowed to flow into the evaporator 26 of the indoor unit 2 in which the defrosting operation condition is not satisfied, and the defrosting operation condition is satisfied. The refrigerant compressed by the compressor 10 is caused to flow only into the second evaporator 26. For example, in the example of this embodiment, since the defrosting operation condition of the first indoor unit 2a is satisfied, the first opening / closing device 22a, the second opening / closing device 22b, and the second flow path switching device 28b are closed. The first flow path switching device 28a is in an open state, and the high-temperature and high-pressure refrigerant compressed by the compressor 10 flows to the first evaporator 26a through the bypass passage 100B. Specifically, the high-temperature and high-pressure refrigerant compressed by the compressor 10 is decompressed by the decompression device 14 and flows out of the outdoor unit 1. The refrigerant flowing out of the outdoor unit 1 flows into the first indoor unit 2a, passes through the first flow path switching device 28a, and flows into the first evaporator 26a. The refrigerant flowing into the first evaporator 26a heats the first evaporator 26a and flows out from the first indoor unit 2a. The refrigerant that has flowed out of the first indoor unit 2a flows into the outdoor unit 1, is sucked into the compressor 10, and is compressed again. In this way, the high-temperature and high-pressure refrigerant compressed by the compressor 10 is caused to flow into the evaporator 26 where the defrosting operation condition is satisfied, and the compressor is transferred to another evaporator 26 where the defrosting operation condition is not satisfied. By performing the second defrosting operation that does not allow the refrigerant compressed in 10 to flow in, the defrosting of the evaporator 26 that satisfies the defrosting operation condition can be performed efficiently.

  In step S12, control device 20 determines whether or not the second defrosting operation has ended. Whether or not the second defrosting operation has ended is determined by determining whether or not frost has adhered to the evaporator 26 using, for example, the temperature of the evaporator 26. Note that whether or not the second defrosting operation has ended may be determined based on whether or not the second defrosting operation execution time in which the second defrosting operation has been performed has reached a preset set time. is there. The time for which the second defrosting operation is executed is, for example, 20 to 30 minutes.

  As described above, in the example of this embodiment, the time for executing the first defrosting operation is shorter than the time for executing the second defrosting operation. As a result, in the example of this embodiment, since heating in the first defrosting operation of the evaporator 26 that does not perform defrosting is suppressed, an increase in the temperature of the room in which the evaporator 26 is installed is suppressed. . Moreover, in the example of this embodiment, since the evaporator 26 that performs defrosting is efficiently heated by the first defrosting operation and the second defrosting operation, the temperature of the room in which the evaporator 26 is installed The rise is suppressed.

  When it is determined in step S12 that the second defrosting operation has been completed, in step S14, the refrigeration apparatus 100 resumes the cooling operation and returns to step S04. That is, the first opening / closing device 22a and the second opening / closing device 22b are opened, the first flow path switching device 28a and the second flow path switching device 28b are closed, and the refrigerant flows into the compressor 10, the condenser 12, and the expansion. By circulating the refrigerant circuit 100A in the order of the device 24 and the evaporator 26, the cooling of the room in which the evaporator 26 is installed is resumed.

  As described above, the refrigeration apparatus 100 of the example of this embodiment includes the refrigerant circuit 100A that connects the compressor 10, the condenser 12, the expansion device 24, and the evaporator 26 with the refrigerant pipe, and circulates the refrigerant. When performing a defrosting operation for defrosting the evaporator 26, the evaporator 26 includes a flow path switching device 28 that forms a flow path for allowing the refrigerant compressed by the compressor 10 to flow into the evaporator 26. When the defrosting operation is performed, the first defrosting operation is performed in which the refrigerant compressed by the compressor 10 is caused to flow into all the evaporators 26, and then one or more The second defrosting operation is performed in which the refrigerant compressed by the compressor 10 flows into the evaporator 26 and the refrigerant compressed by the compressor 10 does not flow into the other evaporator 26. In the refrigeration apparatus 100 of the example of this embodiment, when performing the defrosting operation, the pressure of the refrigerant discharged from the compressor 10 is quickly increased by the first defrosting operation, and the subsequent second defrosting operation is performed. Since the evaporator 26 is selectively defrosted, the defrosting operation can be completed in a short time. According to the refrigeration apparatus 100 of the example of this embodiment, since the defrosting operation can be completed in a short time, an increase in the temperature of the room in which the evaporator 26 is installed can be suppressed. As a result, according to the refrigeration apparatus 100 of the example of this embodiment, the possibility that the quality of the product to be cooled that is cooled in the room where the evaporator 26 is installed is suppressed. Furthermore, according to the refrigeration apparatus 100 of the example of this embodiment, since the defrosting operation can be completed in a short time, the power required for the defrosting operation is reduced. The effect of rapidly increasing the pressure of the refrigerant discharged from the compressor 10 by the first defrosting operation is particularly remarkable when the temperature outside the room where the evaporator 26 is installed is low.

  For example, in the second defrosting operation, the refrigerant compressed by the compressor 10 is allowed to flow into one evaporator 26 and the refrigerant compressed by the compressor 10 is not allowed to flow into the other evaporator 26. The time for executing the defrosting operation can be further shortened.

  For example, when the defrosting operation conditions of a plurality of indoor units 2 are satisfied, the second defrosting operation may be executed in order from the indoor unit 2 having the highest priority of the defrosting operation. Then, after the second defrosting operation is completed and the cooling operation is performed, the defrosting operation of the indoor unit 2 having a low priority of the defrosting operation is performed. In addition, the priority of the defrosting operation of the indoor unit 2 is set in advance, for example, and is stored in a storage unit that is not illustrated.

  Further, for example, the time for executing the first defrosting operation is shorter than the time for executing the second defrosting operation. For example, the time for executing the first defrosting operation is 1/3 to 1/5 of the time for executing the second defrosting operation. By shortening the time for performing the first defrosting operation, the heating in the first defrosting operation of the evaporator 26 that does not perform the defrosting is suppressed, so that the temperature in the room where the evaporator 26 is installed increases. Is suppressed. Furthermore, in the example of this embodiment, since the evaporator 26 that performs defrosting is efficiently heated by the first defrosting operation and the second defrosting operation, the temperature of the room in which the evaporator 26 is installed The rise is suppressed.

  Further, for example, the plurality of evaporators 26 are installed in the same room, and temperature unevenness in the room in which the evaporator 26 is installed is suppressed.

  Further, for example, it has a bypass 100B that branches from between the compressor 10 and the condenser 12 and allows the refrigerant compressed by the compressor 10 to flow into the evaporator 26, and the flow path switching device 28 is connected to the bypass 100B. It is arranged. The bypass passage 100B is provided with a decompression device 14 for reducing the pressure of the refrigerant flowing through the bypass passage 100B, and the pressure of the refrigerant flowing through the bypass passage 100B is reduced to flow into the evaporator 26. It is possible to use an evaporator 26 having a low performance.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. That is, the configuration of the above embodiment may be improved as appropriate, or at least a part of the configuration may be replaced with another configuration. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

  For example, in the above description, the refrigeration apparatus 100 that defrosts the evaporator 26 by flowing a high-temperature and high-pressure refrigerant through the bypass passage 100B has been described. However, the refrigeration apparatus is, for example, a flow path switching device such as a four-way valve. And a reverse defrost type that performs a defrosting operation by switching the direction of the refrigerant flowing in the refrigerant circuit. Even in the reverse defrost type refrigeration apparatus, the defrosting of the evaporator can be completed in a short time by executing the first defrosting operation and the second defrosting operation.

  1 outdoor unit, 2 indoor unit, 2a first indoor unit, 2b second indoor unit, 10 compressor, 12 condenser, 14 decompression device, 16 control device, 20 control device, 20a first control device, 20b second control Device, 22 opening and closing device, 22a first opening and closing device, 22b second opening and closing device, 24 expansion device, 24a first expansion device, 24b second expansion device, 26 evaporator, 26a first evaporator, 26b second evaporator, 28 channel switching device, 28a first channel switching device, 28b second channel switching device, 100 refrigeration device, 100A refrigerant circuit, 100B bypass channel.

Refrigeration apparatus according to the present invention includes a plurality of indoor units each having an evaporator, a compressor, a condenser and the expansion device and a plurality of the evaporator connected by refrigerant pipes, a refrigerant circuit for circulating a refrigerant, wherein the evaporator when performing a defrosting operation for defrosting, anda flow path switching unit for forming a is to channel flow into the compressed refrigerant to the evaporator at the compressor, all of the evaporator Is connected in parallel to the compressor and the condenser via the refrigerant circuit, and when the defrosting operation is performed, the refrigerant compressed by the compressor flows into all the evaporators. The first defrosting operation is performed, and then the refrigerant compressed by the compressor is allowed to flow into one or more of the evaporators, and the refrigerant compressed by the compressor is not allowed to flow into the other evaporators. The frost operation is executed.

Claims (7)

A compressor, a condenser, an expansion device, and an evaporator are connected by a refrigerant pipe, and a refrigerant circuit for circulating the refrigerant is provided.
When performing a defrosting operation for defrosting the evaporator, a flow path switching device that forms a flow path for allowing the refrigerant compressed by the compressor to flow into the evaporator,
Two or more evaporators are connected in parallel,
When the defrosting operation is performed, a first defrosting operation is performed in which the refrigerant compressed by the compressor flows into all the evaporators, and then the one or more evaporators are compressed by the compressor. A second defrosting operation is performed in which the refrigerant that has been flown in and the refrigerant that has been compressed by the compressor in the other evaporator is not flown in,
Refrigeration equipment. In the second defrosting operation, the refrigerant compressed by the compressor is allowed to flow into one of the evaporators, and the refrigerant compressed by the compressor is not allowed to flow into another evaporator.
The refrigeration apparatus according to claim 1. The time for executing the first defrosting operation is shorter than the time for executing the second defrosting operation,
The refrigeration apparatus according to claim 1 or 2. The time for executing the first defrosting operation is 1/3 to 1/5 or less of the time for executing the second defrosting operation.
The refrigeration apparatus according to claim 3. A plurality of the evaporators are installed in the same room,
The refrigeration apparatus according to any one of claims 1 to 4. Branching between the compressor and the condenser, and having a bypass for allowing the refrigerant compressed by the compressor to flow into the evaporator,
The flow path switching device is disposed in the bypass path,
The refrigeration apparatus according to any one of claims 1 to 5. A pressure reducing device that is disposed in the bypass passage and reduces the pressure of the refrigerant flowing in the bypass passage;
The refrigeration apparatus according to claim 6.

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