JP2004163084A - Vapor compression type refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor compression type refrigerator capable of reducing defrosting operation time. <P>SOLUTION: The refrigerator is constituted to stop hot water supply to a water refrigerant heat exchanger 20 during a defrosting operation, fully open a valve 61 in a stopped state of outside air blowing to an evaporator 40, and increase opening of an expansion valve 30 to a value that is equivalent to a pressure not higher than a withstanding pressure of the evaporator 40 and provides a temperature allowing heating of the evaporator 40. Thus, hot refrigerant that has little been cooled by the water refrigerant heat exchanger 20 is distributed and supplied to the evaporator 40 and an accumulator 50, so that hot refrigerant can be supplied also to the accumulator 50. As a result, many refrigerants having flown into the accumulator 50 can be suppressed from being condensed and liquified, so that gas phase refrigerant amount supplied from the accumulator 50 to a compressor 10 can be prevented from decreasing comparing with hot gas amount discharged from the compressor. Much hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vapor compression refrigerator, and is effective when applied to equipment utilizing the heat generated by the vapor compression refrigerator, such as a water heater or a heating device.
[0002]
Problems to be solved by the prior art and the invention
FIGS. 11 and 12 are schematic diagrams of a general vapor compression refrigerator that mainly uses heat, such as a water heater and a heating device.
[0003]
In the vapor compression refrigerator shown in FIG. 11, when removing frost generated in the low-temperature side heat exchanger (evaporator) 40, that is, at the time of the defrosting operation, the expansion valve 30 is almost fully opened to set the high-pressure side heat exchange. The high-pressure refrigerant (hot gas) flowing out of the heat exchanger 20 is guided to the low-temperature side heat exchanger 40 without depressurization, thereby heating the low-pressure side heat exchanger 40 and the gas-liquid separator 50, and the vapor compression refrigeration shown in FIG. When the defrosting operation is performed in the machine, the bypass passage is opened with the expansion valve 30 closed, and the hot gas is guided to the low-temperature side heat exchanger 40 so that the low-pressure side heat exchanger 40 and the gas-liquid separator 50 are connected. Heating.
[0004]
By the way, the low-pressure side heat exchanger and the gas-liquid separator belong to the low-pressure side in the vapor compression type refrigerator and are substantially isothermal and at equal pressure, and the low-pressure side heat exchanger and the gas-liquid separator On the other hand, since they are connected in series, the gas-liquid separator has to be heated by the refrigerant whose temperature has decreased by heating the low-pressure side heat exchanger.
[0005]
Because of this, much of the refrigerant flowing out of the low-pressure side heat exchanger and flowing into the gas-liquid separator is condensed and liquefied, and the amount of gas-phase refrigerant supplied from the gas-liquid separator to the compressor is reduced. Is smaller than the amount of hot gas discharged from the nozzle.
[0006]
Further, in the low-pressure side heat exchanger, the hot gas flows through the defrosting completed portion, so that heat dissipation loss occurs. Therefore, there is a problem that much time is required for the defrosting operation.
[0007]
SUMMARY OF THE INVENTION In view of the above points, the present invention firstly provides a new vapor compression refrigerator different from the conventional one, and secondly, aims to shorten the defrosting operation time.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there is provided a vapor compression refrigerator for transferring heat on a low temperature side to a high temperature side, wherein the compressor compresses a refrigerant by suction. A high-pressure heat exchanger (20) for cooling the compressed high-pressure refrigerant, a low-pressure heat exchanger (40) for evaporating the depressurized low-pressure refrigerant, and a compressor (10) provided on the suction side, A gas-liquid separator (50) for separating the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and supplying the gas-phase refrigerant to the compressor (10), and frost generated in the low-pressure side heat exchanger (40). Is removed, high-temperature refrigerant not cooled in the high-pressure side heat exchanger (20) is distributed and supplied to the low-pressure side heat exchanger (40) and the gas-liquid separator (50), respectively. Features.
[0009]
Thereby, since it is possible to suppress a large amount of refrigerant flowing into the gas-liquid separator (50) from being condensed and liquefied, the amount of the gas-phase refrigerant supplied from the gas-liquid separator (50) to the compressor (10) is reduced. It is possible to prevent the amount of hot gas discharged from the compressor from becoming smaller than the amount of hot gas discharged. Since a large amount of hot gas can be supplied to the low-pressure side heat exchanger (40), the defrosting operation time can be shortened.
[0010]
According to a second aspect of the present invention, there is provided a vapor compression refrigerator for transferring heat on a low temperature side to a high temperature side, and a compressor (10) for sucking and compressing a refrigerant, and a high pressure side for cooling a compressed high-pressure refrigerant. A heat exchanger (20), a decompressor (30) for decompressing and expanding the refrigerant flowing out of the high-pressure side heat exchanger (20) in an isenthalpy manner, and evaporating the low-pressure refrigerant depressurized by the decompressor (30). Gas-liquid provided on the suction side of the low-pressure side heat exchanger (40) and the compressor (10) to separate the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and supply the gas-phase refrigerant to the compressor (10) When removing the frost generated in the separator (50) and the low-pressure side heat exchanger (40), the high-temperature refrigerant not cooled in the high-pressure side heat exchanger (20) is distributed to remove the low-pressure side heat. It is supplied to the exchanger (40) and the gas-liquid separator (50), respectively.
[0011]
Thereby, since it is possible to suppress a large amount of refrigerant flowing into the gas-liquid separator (50) from being condensed and liquefied, the amount of the gas-phase refrigerant supplied from the gas-liquid separator (50) to the compressor (10) is reduced. It is possible to prevent the amount of hot gas discharged from the compressor from becoming smaller than the amount of hot gas discharged. Since a large amount of hot gas can be supplied to the low-pressure side heat exchanger (40), the defrosting operation time can be shortened.
[0012]
According to the third aspect of the present invention, there is provided a vapor compression type refrigerator for transferring heat of a low temperature side to a high temperature side, wherein the high pressure side heat exchanger (20) radiating heat of the high pressure refrigerant discharged from the compressor (10). ), A low-pressure side heat exchanger (40) for evaporating the low-pressure refrigerant, and a nozzle (71) for decompressing and expanding the high-pressure refrigerant in an isentropic manner. An ejector (70) that sucks the vaporized refrigerant evaporated in the side heat exchanger (40), converts expansion energy into pressure energy to increase the suction pressure of the compressor (10), and an ejector (70). The discharged refrigerant is separated into a gas-phase refrigerant and a liquid-phase refrigerant, an outlet for the gas-phase refrigerant is connected to the suction side of the compressor (10), and an outlet for the liquid-phase refrigerant is connected to the low-pressure side heat exchanger (40). Gas-liquid separator (50) When removing the frost generated in the side heat exchanger (40), the high-temperature refrigerant not cooled in the high-pressure side heat exchanger (20) is distributed, and the low-pressure side heat exchanger (40) and the gas-liquid It is characterized in that it is supplied to each of the separators (50).
[0013]
Thereby, since it is possible to suppress a large amount of refrigerant flowing into the gas-liquid separator (50) from being condensed and liquefied, the amount of the gas-phase refrigerant supplied from the gas-liquid separator (50) to the compressor (10) is reduced. It is possible to prevent the amount of hot gas discharged from the compressor from becoming smaller than the amount of hot gas discharged. Since a large amount of hot gas can be supplied to the low-pressure side heat exchanger (40), the defrosting operation time can be shortened.
[0014]
In the invention according to claim 4, the compressor (10) is a multi-stage compressor that compresses the refrigerant in a plurality of stages, and removes frost generated in the low-pressure side heat exchanger (40). Is characterized in that refrigerant is distributed during a compression stroke from a first stage discharge to a final discharge of the compressor (10).
[0015]
According to a fifth aspect of the present invention, when the heat on the low temperature side is moved to the high temperature side, the discharge pressure of the compressor (10) is set to be equal to or higher than the critical pressure of the refrigerant.
[0016]
The invention according to claim 6 is characterized in that carbon dioxide is used as the refrigerant.
[0017]
Incidentally, the reference numerals in parentheses of the respective means are examples showing the correspondence with specific means described in the embodiments described later.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
In the present embodiment, the steam compression refrigerator according to the present invention is applied to a water heater, and FIG. 1 is a schematic diagram of the steam compression refrigerator according to the embodiment.
[0019]
The compressor 10 sucks and compresses the refrigerant. In the present embodiment, an electric compressor in which an electric motor and a compression mechanism are integrated is employed. The water-refrigerant heat exchanger 20 is a high-pressure side heat exchanger that heats hot water by exchanging heat between the hot water and the high-temperature high-pressure refrigerant discharged from the compressor 10. Since the pressure is equal to or higher than the critical pressure of the refrigerant and the desired temperature is obtained, the refrigerant in the water-refrigerant heat exchanger 20 decreases the enthalpy while lowering the temperature without condensation (phase change). Incidentally, in the present embodiment, carbon dioxide is employed as the refrigerant.
[0020]
The expansion valve 30 is a decompressor that decompresses and expands the refrigerant flowing out of the water-refrigerant heat exchanger 20 in an isenthalpic manner. In the present embodiment, the pressure of the high-pressure side refrigerant is controlled within a predetermined range by an electronic control unit (not shown). The throttle opening of the expansion valve 30 is variably controlled such that
[0021]
The evaporator 40 is a low-temperature side heat exchanger that evaporates the low-pressure refrigerant decompressed by the expansion valve 30. The accumulator 50 is provided on the suction side of the compressor 10 and converts the refrigerant flowing into the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant. And a gas-liquid separator for supplying the gas-phase refrigerant to the compressor 10 after being separated into the gaseous refrigerant.
[0022]
The oil return circuit 51 is a passage for returning the refrigerating machine oil separated by the density difference to the suction side of the compressor 10. Incidentally, the refrigerating machine oil is a lubricating oil for lubricating a sliding portion in the compressor 10, and in a vapor compression type refrigerating machine, usually, the refrigerating machine oil is mixed with a refrigerant to be supplied to the compressor 10. I have.
[0023]
The bypass circuit 60 is a refrigerant passage that guides the refrigerant flowing out of the expansion valve 30 to the accumulator 50 by bypassing the evaporator 40. The bypass circuit 60 includes a valve 61 that controls the amount of refrigerant flowing into the bypass circuit 60. The valve 61 is controlled by the above-described electronic control device.
[0024]
Next, the characteristic operation of this embodiment and its effects will be described.
[0025]
In a case where the outside air temperature is a first predetermined temperature (for example, 0 ° C.) T1 of 0 ° C. or less and the difference between the outside air temperature and the temperature of the refrigerant flowing out of the evaporator 40 becomes equal to or more than a predetermined value, Assuming that frost has occurred in the evaporator 40, the following defrosting operation is performed.
[0026]
That is, while the supply of hot water to the water-refrigerant heat exchanger 20 is stopped and the supply of outside air to the evaporator 40 is stopped, the valve 61 is fully opened, and the opening degree of the expansion valve 30 is adjusted by the evaporator. The pressure is equal to or lower than the pressure resistance pressure of 40 and the evaporator 40 can be heated, that is, it is opened to a pressure corresponding to a temperature higher than the outside air temperature.
[0027]
As a result, the high-temperature refrigerant that is hardly cooled in the water-refrigerant heat exchanger 20 is distributed and supplied to each of the evaporator 40 and the accumulator 50. Supplied.
[0028]
Therefore, since a large amount of refrigerant flowing into the accumulator 50 can be suppressed from being condensed and liquefied, the amount of gas-phase refrigerant supplied to the compressor 10 from the accumulator 50 is smaller than the amount of hot gas discharged from the compressor. Can be prevented. As a result, a large amount of hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced.
[0029]
(2nd Embodiment)
This embodiment is a modification of the first embodiment. In this embodiment, as shown in FIG. 2, the refrigerant discharged from the compressor 10 bypasses the water refrigerant heat exchanger 20 and the expansion valve 30 to evaporate. A bypass circuit 62 for distributing and supplying to each of the accumulator 50 and the accumulator 50 is provided, and a valve 63 for controlling the amount of refrigerant flowing into the bypass circuit 62 is controlled by the above-mentioned electronic control device.
[0030]
Accordingly, if the valve 63 is opened with the expansion valve 30 closed during the defrosting operation, the high-temperature refrigerant not cooled by the water-refrigerant heat exchanger 20 is distributed and supplied to the evaporator 40 and the accumulator 50, respectively. The high-temperature refrigerant is supplied not only to the evaporator 40 but also to the accumulator 50.
[0031]
Therefore, since a large amount of refrigerant flowing into the accumulator 50 can be suppressed from being condensed and liquefied, the amount of gas-phase refrigerant supplied to the compressor 10 from the accumulator 50 is smaller than the amount of hot gas discharged from the compressor. Can be prevented. As a result, a large amount of hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced.
[0032]
(Third embodiment)
In the present embodiment, as shown in FIG. 3, a multi-stage compressor that compresses refrigerant in a plurality of stages is employed as the compressor 10, and during the defrosting operation, the compressor 10 is discharged from the first stage to the final stage. And distributes the refrigerant during the compression stroke.
[0033]
The valves 60a and 60b regulate the amount of the refrigerant flowing through the bypass circuits 60c and 60d. The check valve 60e is a check valve for preventing the refrigerant from flowing backward from the evaporator 40 to the discharge side of the compressor 10. It is a valve.
[0034]
FIG. 3A shows an example in which a high-temperature refrigerant is introduced from the first-stage discharge side of the compressor 10 to the accumulator 50, and a high-temperature refrigerant is introduced from the final discharge side of the compressor 10 to the evaporator 40. FIG. This is an example in which a high-temperature refrigerant is guided to an accumulator 50 from a final discharge side of the compressor 10 and a high-temperature refrigerant is guided to an evaporator 40 from a first discharge side of the compressor 10.
[0035]
Although FIG. 3 shows a two-stage compression method, it goes without saying that a three-stage or more compression method may be used.
[0036]
(Fourth embodiment)
In the above embodiment, a water heater using a vapor compression refrigerator (expansion valve cycle) using a decompressor that decompresses and expands a refrigerant in an isenthalpic manner is used. However, in this embodiment, as shown in FIG. In addition, an ejector cycle is used as a vapor compression refrigerator.
[0037]
Here, the ejector cycle has a nozzle 71 that decompresses and expands the high-pressure refrigerant in an isentropic manner, and aspirates the vapor-phase refrigerant evaporated in the evaporator 40 by the high-speed refrigerant flow injected from the nozzle 71, This is a vapor compression refrigerator using an ejector 70 that converts expansion energy into pressure energy to increase the suction pressure of the compressor 10. In the present embodiment, the throttle opening of the nozzle 71 is determined by the pressure of the high-pressure side refrigerant. It is variably controlled to be within a predetermined range.
[0038]
Further, the driving flow ejected from the nozzle 71 and the suction flow sucked from the evaporator 40 are mixed in the mixing section 72 so that their momentums are preserved, and the pressure is increased. The expanding diffuser 73 converts the dynamic pressure into a static pressure and further increases the pressure.
[0039]
In the present embodiment, a bypass circuit 64 that distributes and supplies the refrigerant discharged from the compressor 10 to the evaporator 40 and the accumulator 50 by bypassing the water-refrigerant heat exchanger 20 and the ejector 70 is provided. The valve 65 for controlling the amount of refrigerant flowing in is controlled by an electronic control unit.
[0040]
In the ejector cycle, the accumulator 50 → the evaporator 40 → the ejector 70 (mixing section 72 → diffuser 73) → accumulator 50 in the order of the pumping action of the ejector 70 (see JIS Z 8126 No. 2.1.2.3). The refrigerant circulates, and the refrigerant circulates in the order of the compressor 10, the water refrigerant heat exchanger 20, the ejector 70, the accumulator 50, and the compressor 10 by the pump action of the compressor 10.
[0041]
For this reason, the accumulator 50 separates the refrigerant flowing out of the ejector 70 into a gas-phase refrigerant and a liquid-phase refrigerant, the outlet for the gas-phase refrigerant is connected to the suction side of the compressor 10, and the outlet for the liquid-phase refrigerant is connected to the evaporator. 40.
[0042]
Next, the operation and effect of the present embodiment will be described.
[0043]
If the valve 65 is opened with the nozzle 71 closed during the defrosting operation, the high-temperature refrigerant not cooled by the water-refrigerant heat exchanger 20 is distributed and supplied to the evaporator 40 and the accumulator 50, respectively. Needless to say, the accumulator 50 is also supplied with a high-temperature refrigerant.
[0044]
Therefore, since a large amount of refrigerant flowing into the accumulator 50 can be suppressed from being condensed and liquefied, the amount of gas-phase refrigerant supplied to the compressor 10 from the accumulator 50 is smaller than the amount of hot gas discharged from the compressor. Can be prevented. As a result, a large amount of hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced.
[0045]
FIG. 5 shows the temperature change of the evaporator 40 and the accumulator 50 of the vapor compression refrigerator according to the present embodiment, and the temperature of the evaporator 40 and the accumulator 50 of the vapor compression refrigerator according to the conventional technology (FIG. 11). This indicates that the defrosting operation time of the vapor compression refrigerator according to the present embodiment is shorter than that of the related art.
[0046]
(Fifth embodiment)
In the fourth embodiment, the high-pressure side of the bypass circuit 64 is connected to the refrigerant inlet side of the water-refrigerant heat exchanger 20. However, in the present embodiment, as shown in FIG. It is connected to the refrigerant outlet side of the exchanger 20. The control operations of the valve 65 and the nozzle 71 are the same as in the fourth embodiment.
[0047]
(Sixth embodiment)
This embodiment also uses an ejector cycle. In this embodiment, as shown in FIG. 7, a bypass circuit 66 that guides the refrigerant flowing out of the ejector 70 to the refrigerant inlet side of the evaporator 40 by bypassing the accumulator 50. And a valve 67 for controlling the amount of refrigerant flowing into the bypass circuit 66 is controlled by an electronic control unit.
[0048]
Next, the characteristic operation of this embodiment and its effects will be described.
[0049]
During the defrosting operation, the supply of hot water to the water / refrigerant heat exchanger 20 is stopped, and the valve 67 is fully opened in a state in which outside air blowing to the evaporator 40 is stopped. The pressure is equal to or lower than the pressure resistance of the evaporator 40 and the evaporator 40 can be heated, that is, the pressure is increased to a pressure corresponding to a temperature higher than the outside air temperature.
[0050]
As a result, the high-temperature refrigerant that is hardly cooled in the water-refrigerant heat exchanger 20 is distributed and supplied to each of the evaporator 40 and the accumulator 50. Supplied.
[0051]
Therefore, since a large amount of refrigerant flowing into the accumulator 50 can be suppressed from being condensed and liquefied, the amount of gas-phase refrigerant supplied to the compressor 10 from the accumulator 50 is smaller than the amount of hot gas discharged from the compressor. Can be prevented. As a result, a large amount of hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced.
[0052]
(Seventh embodiment)
In the sixth embodiment, a two-way valve is adopted as the valve 67, but in the present embodiment, a three-way valve is adopted as the valve 67 as shown in FIG. The flow of the refrigerant is the same as in the sixth embodiment.
[0053]
Incidentally, in FIG. 8, the valve 67 is arranged on the side of the evaporator 40 of the bypass circuit 66, but it is needless to say that the valve 67 may be arranged on the side of the ejector 70 of the bypass circuit 66.
[0054]
(Eighth embodiment)
This embodiment also uses an ejector cycle. In this embodiment, as shown in FIG. 9, a bypass circuit 68 for guiding refrigerant flowing out of the ejector 70 to the ejector 70 side of the evaporator 40 is provided. A valve 69 for controlling the amount of refrigerant flowing into the valve 68 is controlled by an electronic control unit.
[0055]
Next, the characteristic operation of this embodiment and its effects will be described.
[0056]
During the defrosting operation, the supply of hot water to the water / refrigerant heat exchanger 20 is stopped, and the outside air blow to the evaporator 40 is stopped to operate the valve 69 to connect the bypass circuit 68 to the evaporator 40. At the same time, the opening degree of the nozzle 71 is equal to or lower than the pressure resistance of the evaporator 40 and the evaporator 40 can be heated, that is, opened to a pressure corresponding to a temperature higher than the outside air temperature.
[0057]
As a result, the high-temperature refrigerant that has not been substantially cooled by the water-refrigerant heat exchanger 20 is distributed and supplied to each of the evaporator 40 and the accumulator 50, so that the high-temperature refrigerant is stored not only in the evaporator 40 but also in the accumulator 50. Supplied.
[0058]
Therefore, since a large amount of refrigerant flowing into the accumulator 50 can be suppressed from being condensed and liquefied, the amount of gas-phase refrigerant supplied to the compressor 10 from the accumulator 50 is smaller than the amount of hot gas discharged from the compressor. Can be prevented. As a result, a large amount of hot gas can be supplied to the evaporator 40, so that the defrosting operation time can be reduced.
[0059]
Note that, other than during the defrosting operation, that is, when heat is absorbed by the evaporator 40, the ejector 70 and the evaporator 40 are communicated, and the valve 69 is operated so as to close the bypass circuit 68 side.
[0060]
(Ninth embodiment)
This embodiment is a modification of the fourth embodiment.
[0061]
That is, in the fourth embodiment, the bypass circuit 64 is connected to the refrigerant pipe connecting the accumulator 50 and the evaporator 40. However, in the present embodiment, the bypass circuit 64 is connected to the ejector 70 and the evaporator 40 as shown in FIG. The hot gas is supplied to the bypass circuit 64 with the nozzle 71 closed during the defrosting operation.
[0062]
Thereby, during the defrosting operation, the hot gas discharged from the compressor 10 flows into the circuit connecting the evaporator 40 and the ejector 70 via the bypass circuit 64, and the hot gas flowing to the evaporator 40 and the ejector The gas is separated into hot gas flowing into the gas-liquid separator 50 via 70.
[0063]
Incidentally, the hot gas flowing into the ejector 70 reaches the gas-liquid separator 50 via the mixing unit 72 and the diffuser 73 because the nozzle 71 is closed.
[0064]
Therefore, the hot gas is distributed and supplied to both the accumulator 5 and the evaporator 40, so that the defrosting operation time can be reduced.
[0065]
(Other embodiments)
In the above embodiment, the present invention has been described by taking a water heater as an example. However, the present invention is not limited to this, and can be applied to a vapor compression refrigerator using cold heat in a freezer or the like.
[0066]
In the above-described embodiment, in the example in which the bypass circuit 64 is opened and closed by the two-way valve, a three-way valve is provided at a portion connecting the bypass circuit 64 and the discharge side of the compressor 10 instead of the two-way valve. You may.
[0067]
In the above-described embodiment, the refrigerant is carbon dioxide and the high pressure side pressure is equal to or higher than the critical pressure. However, the present invention is not limited to this.
[0068]
Further, in the above-described embodiment, the case where the outside air temperature is the first predetermined temperature (for example, 0 ° C.) T1 of 0 ° C. or less, and the difference between the outside air temperature and the temperature of the refrigerant flowing out of the evaporator 40 is the predetermined temperature When the value became equal to or more than the value, the defrosting operation was performed assuming that the frost generated in the evaporator 40 was generated. However, the present invention is not limited to this. The defrosting operation may be performed periodically.
[Brief description of the drawings]
FIG. 1 is a schematic view of a vapor compression refrigerator according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram of a vapor compression refrigerator according to a second embodiment of the present invention.
FIG. 3 is a schematic view of a vapor compression refrigerator according to a third embodiment of the present invention.
FIG. 4 is a schematic view of a vapor compression refrigerator according to a fourth embodiment of the present invention.
FIG. 5 is a graph showing a temperature change of an evaporator and an accumulator of a vapor compression refrigerator according to a fourth embodiment of the present invention, and a temperature change of an evaporator and an accumulator of a vapor compression refrigerator according to the related art. is there.
FIG. 6 is a schematic diagram of a vapor compression refrigerator according to a fifth embodiment of the present invention.
FIG. 7 is a schematic diagram of a vapor compression refrigerator according to a sixth embodiment of the present invention.
FIG. 8 is a schematic view of a vapor compression refrigerator according to a seventh embodiment of the present invention.
FIG. 9 is a schematic view of a vapor compression refrigerator according to an eighth embodiment of the present invention.
FIG. 10 is a schematic view of a vapor compression refrigerator according to a ninth embodiment of the present invention.
FIG. 11 is a schematic view of a vapor compression refrigerator according to a conventional technique.
FIG. 12 is a schematic diagram of a vapor compression refrigerator according to a conventional technique.
[Explanation of symbols]
10: compressor, 20: water refrigerant heat exchanger, 30: expansion valve, 40: evaporator,
50: accumulator, 61: valve.

Claims (6)

A vapor compression refrigerator that transfers heat on the low temperature side to the high temperature side,
A compressor (10) for sucking and compressing the refrigerant;
A high-pressure side heat exchanger (20) for cooling the compressed high-pressure refrigerant;
A low-pressure side heat exchanger (40) for evaporating the depressurized low-pressure refrigerant;
A gas-liquid separator (50) provided on the suction side of the compressor (10) to separate the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and supply the gas-phase refrigerant to the compressor (10); And
When removing the frost generated in the low-pressure side heat exchanger (40), the high-pressure refrigerant not cooled by the high-pressure side heat exchanger (20) is distributed to the low-pressure side heat exchanger (40). ) And the gas-liquid separator (50). A vapor compression refrigerator that transfers heat on the low temperature side to the high temperature side,
A compressor (10) for sucking and compressing the refrigerant;
A high-pressure side heat exchanger (20) for cooling the compressed high-pressure refrigerant;
A pressure reducer (30) for decompressing and expanding the refrigerant flowing out of the high-pressure side heat exchanger (20) in an isenthalpy manner;
A low-pressure side heat exchanger (40) for evaporating the low-pressure refrigerant decompressed by the pressure reducer (30);
A gas-liquid separator (50) provided on the suction side of the compressor (10), for separating a refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and supplying the gas-phase refrigerant to the compressor (10);
When removing the frost generated in the low-pressure side heat exchanger (40), the high-pressure refrigerant not cooled by the high-pressure side heat exchanger (20) is distributed to the low-pressure side heat exchanger (40). ) And the gas-liquid separator (50). A vapor compression refrigerator that transfers heat on the low temperature side to the high temperature side,
A high-pressure side heat exchanger (20) for radiating heat of the high-pressure refrigerant discharged from the compressor (10);
A low pressure side heat exchanger (40) for evaporating the low pressure refrigerant,
It has a nozzle (71) for decompressing and expanding a high-pressure refrigerant in an isentropic manner, and sucks a vapor-phase refrigerant evaporated in the low-pressure side heat exchanger (40) by a high-speed refrigerant flow injected from the nozzle (71). An ejector (70) that converts expansion energy into pressure energy to increase the suction pressure of the compressor (10);
The refrigerant flowing out of the ejector (70) is separated into a gas-phase refrigerant and a liquid-phase refrigerant, an outlet for the gas-phase refrigerant is connected to a suction side of the compressor (10), and an outlet for the liquid-phase refrigerant is connected to the low-pressure side. A gas-liquid separator (50) connected to the heat exchanger (40);
When removing the frost generated in the low-pressure side heat exchanger (40), the high-pressure refrigerant not cooled by the high-pressure side heat exchanger (20) is distributed to the low-pressure side heat exchanger (40). ) And the gas-liquid separator (50). The compressor (10) is a multi-stage compressor that compresses a refrigerant in a plurality of stages,
The refrigerant is distributed in a compression stroke from a first stage discharge to a final discharge of the compressor (10) when removing frost generated in the low-pressure side heat exchanger (40). 4. The vapor compression refrigerator according to any one of items 3 to 3. The steam according to any one of claims 1 to 4, wherein when the heat on the low-temperature side is moved to the high-temperature side, the discharge pressure of the compressor (10) is equal to or higher than the critical pressure of the refrigerant. Compression refrigerator. The vapor compression refrigerator according to any one of claims 1 to 4, wherein carbon dioxide is used as the refrigerant.

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