KR100836824B1 - Refrigerant cycle device - Google Patents

Abstract

A refrigerant cycle device is provided to reduce noise and to improve reliability of the refrigerant cycle device by using carbon dioxide as a refrigerant. A refrigerant cycle device comprises a heat exchanger(20). The heat exchanger is prepared in the form of a dual pipe including a first refrigerant pipe(21) and a second refrigerant pipe(22). The first refrigerant pipe is formed therein with a first fluid path(30). High-pressure refrigerant having passed through a gas cooler flows in the first fluid path. A second fluid path(40) is formed between the first and second refrigerant pipes. Low-pressure refrigerant having passed through an evaporator flows in the second fluid path. Refrigerants flowing through the first and second fluid paths are heat-transferred to each other. The heat exchanger has a spiral structure to enlarge a heat-exchange area.

Description

Refrigerant Cycle Device

1 is a refrigerant circuit diagram of a refrigerant cycle apparatus according to the present invention.

2 is a perspective view of a heat exchanger included in a refrigerant cycle apparatus according to an embodiment of the present invention.

3 is a schematic cross-sectional view of the heat exchanger of FIG. 2.

4 is a p-h diagram of a refrigerant cycle of the refrigerant cycle apparatus according to the present invention.

5 is a schematic perspective view illustrating a coupling structure of a heat exchanger and an evaporator of a refrigerant cycle apparatus according to a second embodiment of the present invention.

6 is a schematic perspective view illustrating a coupling structure of a heat exchanger and an evaporator of a refrigerant cycle apparatus according to a third embodiment of the present invention.

7 is a schematic cross-sectional view of the heat exchanger of FIG. 6.

8 is a schematic cross-sectional view of a portion of a heat exchanger according to a modified embodiment of the present invention.

* Description of symbols on the main parts of the drawings *

1: refrigerant cycle device 11: compressor

12 gas cooler 13 expansion valve

14: evaporator 20: heat exchanger

21: first refrigerant pipe 22: second refrigerant pipe

30: First Euro 31,32: Entry and Exit of First Euro

40: 2nd Euro 41, 42: Entry and Exit of the 2nd Euro

The present invention relates to a refrigerant cycle device, and more particularly, to a refrigerant cycle device using nitrous oxide as a refrigerant.

The conventional refrigerant cycle apparatus is comprised with the refrigerant cycle which pipe-connects a compressor, a gas cooler, a decompression device (expansion valve, an expansion valve, etc.), an evaporator, etc. sequentially and annularly.

Freon (R11, R12, R134a, etc.) has been generally used as the refrigerant used in the refrigerant cycle apparatus. However, since Freon is released into the atmosphere, it causes problems such as global warming effects and ozone layer destruction. Therefore, other natural refrigerants such as oxygen (02), carbon dioxide (CO2), and hydrocarbon (HC) which have less environmental impact in recent years ), Ammonia (NH3), and water (H20) are used as a refrigerant research.

Among these natural refrigerants, oxygen and water have low pressures, making it difficult to use them as refrigerants in refrigeration cycles, and ammonia and hydrocarbons are flammable and thus difficult to handle. For this reason, a device using a transcritical refrigerant cycle in which carbon dioxide (CO2) is used as a refrigerant and the high pressure side is operated as a supercritical pressure has been developed.

In such a transcritical refrigerant cycle device, an accumulator is installed on the low pressure side between the outlet side of the evaporator and the suction side of the compressor to prevent the liquid refrigerant from flowing into the compressor, and accumulates the liquid refrigerant in the accumulator to suck only the refrigerant gas into the compressor. It is composed.

However, the conventional refrigerant cycle apparatus requires a large amount of refrigerant charge due to the mounting of the accumulator, and it is difficult to realize the compactness of the refrigerant cycle apparatus.

In order to solve such a problem, Korean Laid-Open Patent Publication (Publication No. 10-2006-41722) discloses a refrigerant cycle device that can prevent a compressor from being damaged by liquid compression without installing an accumulator. .

The refrigerant cycle device disclosed in the above publication is formed by connecting a compressor, a gas cooler, a decompression device, an evaporator and the like in an annular manner, and uses carbon dioxide as a refrigerant, and is a supercritical refrigerant cycle device in which the high pressure side can be supercritical pressure. And an internal heat exchanger for exchanging the refrigerant from the gas cooler and the refrigerant from the evaporator, wherein the internal heat exchanger is disposed in a heat exchangeable manner with the high pressure side flow path through which the refrigerant from the gas cooler flows and the high pressure side flow path. And a low pressure side flow path, wherein the refrigerant flows from the bottom to the high pressure side flow path, and the refrigerant flows from the top to the low pressure side flow path.

However, the refrigerant cycle device disclosed in the above publication allows the refrigerant to flow upward from the bottom of the high pressure side flow path, and the refrigerant flows from the top to the bottom of the low pressure side flow path, thereby accumulating excess refrigerant in the high pressure side flow path and surplus flowing in the low pressure side. The refrigerant can be reduced to a certain level to prevent the introduction of liquid refrigerant into the compressor, but when a large amount of excess liquid refrigerant is included in the refrigerant passing through the evaporator due to a low temperature of the evaporator, the refrigerant from the evaporator The low pressure side flow path through which the refrigerant flows from the top to the bottom has a problem that the liquid refrigerant cannot be completely prevented from flowing into the compressor.

In addition, the high-pressure side flow path has a problem in that the refrigerant flows from the bottom to the upper side, so that the liquid refrigerant flowing to the expansion valve evaporates to generate flash gas, thereby degrading the performance of the expansion valve.

In addition, since the second refrigerant pipe and the first refrigerant pipe of the internal heat exchanger are spaced apart from each other, when the refrigerant flows through the internal heat exchanger or when vibration is transmitted due to the operation of the compressor, the first refrigerant pipe of the internal heat exchanger is transmitted. This vibration, and the vibration caused by the first refrigerant pipe in contact with the second refrigerant pipe has a problem that the noise is generated. In addition, there is a problem in that such a contact is made continuously to reduce the reliability of the refrigerant cycle device when the wear occurs in the first and second refrigerant pipes.

Accordingly, an object of the present invention is to provide a refrigerant cycle apparatus having a structure capable of preventing miniaturization of liquid refrigerant into a compressor and miniaturization thereof.

In addition, another object of the present invention is to provide a refrigerant cycle device using carbon dioxide having a structure that can reduce noise and improve reliability.

In order to achieve the above object, the present invention provides a refrigerant cycle apparatus including a compressor, a gas cooler, a decompression device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator. A first flow passage connected to an outlet side of the gas cooler and a second flow passage connected to the outlet side of the evaporator, wherein the refrigerant of the first passage flows downward and the refrigerant of the second passage flows upward and heat exchange is performed. It is characterized by performing.

In addition, the outlet of the evaporator is characterized in that it is disposed at a position higher than the inlet of the second passage.

In addition, the refrigerant pipe connecting the outlet of the evaporator and the inlet of the second flow path is characterized in that it is provided to be inclined downward.

The heat exchanger may be formed of a double tube including a first refrigerant pipe and a second refrigerant pipe surrounding the first refrigerant pipe.

The first flow passage may be formed in the first refrigerant pipe, and the second flow passage may be formed between the first and second refrigerant pipes.

The second channel may be formed in the first refrigerant pipe, and the first channel may be formed between the first and second refrigerant pipes.

In addition, a banding portion is formed in the middle of the heat exchanger, and the banding portion is characterized in that the contact portion in contact with the first and second refrigerant pipes is formed.

In addition, the heat exchanger is formed to form a substantially rectangular cross-section, the contact portion is formed in the bent portion of each corner side of the heat exchanger is characterized in that to prevent relative movement between the first and second refrigerant pipes.

In addition, the refrigerant cycle device is characterized in that using the carbon dioxide as a refrigerant.

In another aspect, the present invention provides a refrigerant cycle apparatus including a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator. A first passage connected to an outlet side of a gas cooler and a second passage connected to an outlet side of the evaporator, wherein an inlet of the first passage is provided above the outlet of the first passage, The inlet is provided below the outlet of the second passage.

In addition, the inlet of the first passage is formed at substantially the same height as the outlet of the second passage, the outlet of the first passage is characterized in that it is provided at substantially the same height as the inlet of the second passage.

The refrigerant in the first channel flows downward, and the refrigerant in the second channel flows upward.

In addition, the outlet of the evaporator is characterized in that it is disposed at a position higher than the inlet of the second passage.

In addition, the refrigerant between the outlet of the evaporator and the second flow path is characterized in that flows downward.

The heat exchanger may include a double tube including a first refrigerant pipe and a second refrigerant pipe surrounding the first refrigerant pipe, wherein the first flow path is formed in the first refrigerant pipe, and the second flow path is formed of the first refrigerant pipe. Characterized in that formed between the 1,2 refrigerant pipe.

In addition, the first and second refrigerant pipes are formed with at least one contact portion that is in contact with each other to prevent relative movement between the first and second refrigerant pipes.

In another aspect, the present invention provides a refrigerant cycle apparatus including a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator. The gas is provided in a double pipe, the first refrigerant pipe for flowing the outlet refrigerant of the gas cooler downward, the second refrigerant pipe surrounding the first refrigerant pipe and flowing the outlet refrigerant of the evaporator upwards, and the first, It characterized in that it comprises at least one contact portion which the two refrigerant pipes are in contact with each other.

In another aspect, the present invention provides a refrigerant cycle apparatus including a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator. The apparatus includes a first refrigerant pipe provided as a double pipe to flow the refrigerant at the outlet side of the gas cooler downwardly, and a second refrigerant tube to surround the first refrigerant pipe and to flow the refrigerant at the outlet side of the evaporator upward. It extends inclined downward from the outlet of the characterized in that it comprises a refrigerant pipe for connecting the second refrigerant pipe.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a refrigerant circuit diagram of a refrigerant cycle apparatus according to an embodiment of the present invention.

The refrigerant cycle device of the present invention is used in an air conditioner, a refrigerator or a showcase.

As shown in FIG. 1, a refrigerant cycle apparatus according to an exemplary embodiment of the present invention has an annular connection between a compressor 11, a gas cooler 12, an expansion valve 13 as a pressure reducing device, an evaporator 14, and the like. Consists of.

The compressor 11 is provided between the gas cooler 12 and the evaporator 14. The compressor 11 is used to compress the low-temperature low-pressure gas phase refrigerant into a high-temperature high-pressure gas phase refrigerant. Generally, various types such as hermetic reciprocating type, rotary type, scroll type, etc. Compressors are used.

A refrigerant discharge pipe 2 from the compressor 11 is connected to the inlet of the gas cooler 12. And the pipe 3 connected to the outlet side of the gas cooler 12 is connected to the inlet 31 of the 1st flow path 30 which forms the flow path of the high pressure side refrigerant | coolant in the heat exchanger 20. As shown in FIG.

The heat exchanger 20 is for exchanging the high pressure refrigerant from the gas cooler 12 and the low pressure refrigerant from the evaporator 14 and the outlet 32 of the first flow path 30 of the heat exchanger 20. The pipe 4 connected to) is connected to the evaporator 14 via an expansion valve 13, and the refrigerant pipe 5 on the outlet side of the evaporator 14 receives a flow path of the low pressure refrigerant inside the heat exchanger 20. It is connected to the inlet 41 of the second passage 40 to form.

In addition, the refrigerant heated while passing through the second passage 40 of the heat exchanger 20 is sucked into the compressor 11 through the refrigerant inlet pipe 6 to repeat the refrigerant cycle as described above.

2 is a perspective view of a heat exchanger included in a refrigerant cycle apparatus according to an embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view of the heat exchanger of FIG. 2.

As shown in FIGS. 2 and 3, the heat exchanger 20 included in the refrigerant cycle apparatus according to the exemplary embodiment of the present invention is configured by a double tube including a first refrigerant pipe 21 and a second refrigerant pipe 22. In the first refrigerant pipe 21, a first flow path 30 through which the high-pressure refrigerant passing through the gas cooler 12 flows is formed, and the first refrigerant pipe 21 and the second refrigerant pipe 22 are formed. A second flow passage 40 through which a low-pressure refrigerant flowing through the evaporator 14 flows is formed therebetween, and the refrigerants of the first flow passage 30 and the second flow passage 40 are arranged in such a manner that they can exchange with each other.

Such a double tube heat exchanger 20 is preferably provided in a spiral stacked structure to increase the heat exchange area.

The first passage 30 formed in the heat exchanger 20 has an inlet 31 of the first passage 30 formed at an upper portion of the heat exchanger 20 so that the refrigerant flows from the top to the bottom of the first passage 30. The outlet 32 of is formed at the bottom of the heat exchanger 20. That is, the high pressure side refrigerant from the gas cooler 12 flows into the first flow path 30 through the upper inlet 31 and flows out of the heat exchanger 20 through the lower outlet 32.

An inlet 41 of the second channel 40 is formed in the lower portion of the heat exchanger 20 so that the refrigerant flows from the lower portion to the upper portion of the second channel 40 formed in the heat exchanger 20. The outlet 42 of is formed on top of the heat exchanger 20. That is, the low pressure refrigerant from the evaporator 14 flows into the second flow passage 40 through the lower inlet 41 and flows out of the heat exchanger 20 through the upper outlet 42.

Therefore, the refrigerant passing through the first flow path 30 and the second flow path 40 flows to face each other, whereby the heat exchange capacity of the heat exchanger 20 is improved.

The heat exchanger 20 of the refrigerant cycle apparatus 1 according to the embodiment of the present invention arranges the refrigerant to flow downward in the first flow passage 30 and the refrigerant flows upward in the second flow passage 40 so that the evaporator flows. When the excess liquid refrigerant is discharged from (14), the liquid refrigerant is temporarily stored in the lower portion of the second passage 40 of the heat exchanger 20, and thus functions as an accumulator, so that the compressor is not equipped with a separate accumulator. It is possible to prevent the liquid refrigerant from flowing into (11), and to provide a more stable refrigerant cycle device (1). In addition, since the low-temperature refrigerant passing through the second passage 40 performs heat exchange with the high-temperature refrigerant of the first passage 30, even when the liquid refrigerant is discharged from the evaporator 14, it is regarded as a completely gaseous refrigerant. It can be changed and introduced into the compressor (11).

In addition, since the refrigerant flows downward in the first flow path 30, the liquid refrigerant, which may be generated due to the ambient temperature conditions in the supercritical state, is collected at the lower portion of the first flow path 30, that is, the expansion valve 13, and moves downward. As such, the first flow path 30 serves as a reservoir tank. Therefore, it is possible to prevent the generation of flash gas, and since the refrigerant of the first passage 30 is cooled by heat exchange with the refrigerant of the second passage 40, it is possible to further prevent the generation of flash gas, thereby expanding the expansion valve ( It is possible to prevent the performance degradation of 13), and to stabilize the operation of the refrigerant cycle device.

In addition, as the refrigerant of the refrigerant cycle apparatus 1 according to the present invention, carbon dioxide (CO2), which is friendly to the global environment and takes into consideration flammability and toxicity, is used, and the high pressure side of the refrigerant cycle apparatus 1 is supercritical. Pressure.

The refrigerant introduced into the first flow path 30 flows from the top to the bottom of the first flow path 30. At this time, the refrigerant flowing through the first passage 30 is cooled by depriving heat of the refrigerant flowing through the second passage 40.

The refrigerant on the high pressure side cooled by the heat exchanger 20 and exiting from the lower outlet 32 reaches the expansion valve 13. Such a refrigerant becomes a two-phase mixture of gas / liquid due to the pressure drop by the expansion valve 13 to flow into the evaporator 14, and the refrigerant evaporates while passing through the evaporator 14, thereby exerting a cooling effect by absorbing air. do.

In this process, since the temperature of the refrigerant entering the expansion valve 13 from the gas cooler 12 can be lowered by the heat exchanger 20, the difference in entropy in the evaporator 14 is enlarged, so that the evaporator 14 It is possible to improve the freezing capacity.

In addition, the refrigerant passing through the evaporator flows into the inlet 41 of the second flow passage 40 formed between the first refrigerant pipe 21 and the second refrigerant pipe 22 of the heat exchanger 20. The refrigerant entering the second flow passage 40 flows from the bottom to the top through the second flow passage 40 between the first refrigerant pipe 21 and the second refrigerant pipe 22.

At this time, since the refrigerant evaporated by the evaporator 14 and discharged at a low temperature is not in a completely gaseous state but a mixture of liquids, the refrigerant passes through the second passage 40 of the heat exchanger 20 to the first passage. When heat exchanged with the refrigerant flowing through the 30, the refrigerant is heated to secure the superheat degree of the refrigerant, and is discharged from the heat exchanger 20 in a completely gaseous state to flow to the inflow side of the compressor 11 through the refrigerant inlet pipe 6. .

Therefore, the present invention can prevent the liquid refrigerant from being sucked into the compressor without installing an accumulator, thereby avoiding problems such as damage to the compressor.

As such, the first passage 30 through which the refrigerant from the gas cooler 12 flows and the second passage 40 through which the refrigerant from the evaporator 14 flows are installed in such a manner as to exchange heat with the first passage 30. By installing a heat exchanger 20 having a lowering temperature of the refrigerant entering the expansion valve 13 from the gas cooler 12 and enlarging the difference in entropy in the evaporator 14, the refrigerating capacity can be improved as well. In addition, even when the heat dissipation of the refrigerant in the gas cooler 12 is not sufficiently performed, the performance of the expansion device due to flash gas generation can be prevented by passing through the heat exchanger 20.

In addition, since the refrigerant passing through the evaporator 14 changes to a refrigerant in a completely gas state while passing through the heat exchanger 20, and the liquid refrigerant is temporarily stored at the lower side of the inlet side of the second flow passage 40, the liquid refrigerant is temporarily stored. It can not be equipped with an accumulator to make the refrigerant cycle device can be compact and the manufacturing cost can be reduced.

In addition, it is possible to accumulate surplus refrigerant having passed through the first flow passage 30 on the expansion valve 13 side, thereby preventing flash gas generation.

Due to the configuration as described above, the refrigerant cycle apparatus according to the present invention can improve the reliability and improve the refrigerating capacity.

In this embodiment, the first flow path is formed in the first refrigerant pipe, the second flow path is formed between the first and second refrigerant pipes, but the second flow path is formed in the first refrigerant pipe, and the first flow path is Of course, it can be formed between the first and second refrigerant pipes.

In addition, the heat exchanger 20 has a double pipe structure composed of the first refrigerant pipe 21 and the second refrigerant pipe 22. However, the heat exchanger 20 is not limited to this, and is configured by stacking steel plates having two flow paths therein. It does not matter.

Also in this case, one flow path is used as the first flow path, the other flow path is the second flow path, and the two flow paths are arranged in a heat exchangeable manner, while the first flow path allows the refrigerant to flow from top to bottom. Of course, the two euros should be configured to flow the refrigerant from the bottom up.

In addition, although the expansion valve 13 is used as a pressure reduction apparatus in this embodiment, it is not limited to this, It is also possible to use an electrical or mechanical expansion valve etc.

Next, the operation of the refrigerant cycle device 1 according to the embodiment of the present invention configured as described above will be described.

4 is a p-h diagram of a refrigerant cycle of the refrigerant cycle apparatus according to the present invention.

In FIG. 4, the vertical axis represents pressure, and the horizontal axis represents enthalpy.

When the compressor 11 is operated, a low pressure refrigerant gas flows into the compressor 11 to be compressed and discharged as a high temperature and high pressure refrigerant gas. At this time, the refrigerant is compressed to the supercritical pressure of the point b of FIG.

The high temperature and high pressure refrigerant flows into the gas cooler 12 to radiate heat to reach point c of FIG. 4, and then flows into the inlet 31 of the first flow path 30 of the heat exchanger 20. The high temperature and high pressure refrigerant introduced into the heat exchanger 20 is cooled by heat exchange with the low temperature low pressure refrigerant introduced from the evaporator 14 into the second flow path 40 to reach point d in FIG. 4.

That is, the high pressure refrigerant flowing into the expansion valve 13 from the gas cooler 12 may be exchanged with the low pressure refrigerant of the second flow path 40 by the heat exchanger 20 to effectively lower the temperature of the high pressure refrigerant. The enthalpy of the refrigerant flowing into the expansion valve 13 is lowered by Δh to the point d of FIG.

The refrigerant on the high pressure side cooled by the heat exchanger 20 and exiting the heat exchanger 20 reaches the expansion valve 13. As the refrigerant passing through the expansion valve 13 is reduced in pressure, it enters the evaporator 14 in a two-phase state of liquid / gas as in point e of FIG. 4, and the refrigerant in the evaporator 14 absorbs heat from air. Demonstrates cooling action.

Therefore, since the temperature of the refrigerant flowing into the evaporator 14 is lowered by the heat exchange action of the heat exchanger 20, the enthalpy difference in the evaporator 14 is increased to improve the freezing capacity of the evaporator 14.

Thereafter, the refrigerant flows out of the evaporator 14 and flows into the inlet 41 of the second flow path 40 of the heat exchanger 20 in the point f of FIG. 4, and the low temperature refrigerant exchanged in the evaporator 14. Since the two phases of the liquid / gas is a state of the two phases of the refrigerant flows through the second passage 40 of the heat exchanger 20, the phase change of the complete gas state to the point a state of Fig. 4 superheat degree Will be able to secure. Therefore, since only the refrigerant in the gas phase flows into the compressor 11, it is possible to prevent problems such as damage to the compressor caused by the liquid refrigerant flowing into the compressor 11.

In addition, the refrigerant heated by the heat exchanger 20 is sucked to repeat the above cycle.

Therefore, the refrigerant cycle apparatus 1 according to the present invention increases both the degree of supercooling and the degree of superheat, the increased degree of subcooling prevents the deterioration of the performance of the evaporator 14, and the increased degree of superheating the liquid refrigerant to the compressor 11. By preventing the inflow improves the reliability of the compressor (11).

Next, a refrigerant cycle device according to a second embodiment of the present invention will be described.

The same configuration as the embodiment of the present invention will be given the same reference numerals and the description thereof will be omitted.

5 is a schematic perspective view illustrating a coupling structure of a heat exchanger and an evaporator of a refrigerant cycle apparatus according to a second embodiment of the present invention.

The heat exchanger of the refrigerant cycle apparatus according to the second embodiment of the present invention is the same as the heat exchanger of the refrigerant cycle apparatus according to the embodiment of the present invention.

However, in the height relationship between the outlet side of the evaporator 14 and the inlet 41 side of the second passage 40 of the heat exchanger 20, the outlet side of the evaporator 14 is the second passage of the heat exchanger 20. It is formed at a position higher than the inlet 41 side of the 40, preferably the evaporator 14 such that the outlet side of the evaporator 14 is located at substantially the same height as the outlet 42 side of the second flow passage 40. ) And the heat exchanger 20.

Therefore, the refrigerant pipe 5 'connecting the outlet side of the evaporator 14 and the inlet 41 side of the second passage 40 is inclined downward toward the inlet 41 side of the second passage 40. do.

Due to such a configuration, a large amount of surplus liquid refrigerant is discharged from the evaporator 14 when the ambient temperature of the evaporator 14 is particularly low, and even in this case, the lower part of the second passage 40 and the outlet of the evaporator 14 are discharged. Since the refrigerant pipe 5 'between the inlet 41 of the second passage 40 performs the function of the accumulator, it is possible to further improve the damage preventing effect of the compressor.

Next, a refrigerant cycle apparatus according to a third embodiment of the present invention will be described.

The same configuration as that of the second embodiment of the present invention is given the same reference numeral and the description thereof will be omitted.

6 is a schematic perspective view illustrating a coupling structure of a heat exchanger and an evaporator of a refrigerant cycle apparatus according to a third embodiment of the present invention, and FIG. 7 is a schematic cross-sectional view of the heat exchanger of FIG. 6.

As shown in FIGS. 6 and 7, the heat exchanger of the refrigerant cycle apparatus according to the third embodiment of the present invention has a double tube heat exchanger 50 having a substantially rectangular cross section and is stacked in a spiral shape. In order to achieve this, the bending portion 53 is formed to have a predetermined length in the middle of the heat exchanger 50.

By bending the heat exchanger 50 as described above, the first and second refrigerant pipes 51 and 52 having a double tube shape are brought into contact with each other at the bending portion 53 to form a contact portion 54. That is, the first and second refrigerant pipes 51 and 52 are in contact with each of the bending portions 53 of the rectangular cross section.

Therefore, even when the refrigerant flows inside the heat exchanger 50, or when the first and second refrigerant pipes 51 and 52 vibrate because vibration occurs in the heat exchanger 50 by driving the compressor 11. Since the first and second refrigerant pipes 51 and 52 remain fixed through the contact portions 53, noise and abrasion generated by the relative movement of the first and second refrigerant pipes 51 and 52 are caused. Can be prevented.

Except for this, the refrigerant cycle apparatus according to the third embodiment and the refrigerant cycle apparatus according to the second embodiment may be provided in the same configuration to have the same effect as the second embodiment.

In addition, as shown in FIG. 8, the heat exchanger 60 is provided by bending the second refrigerant pipe 62 in which the first refrigerant pipe 61 is inserted into the uneven shape to contact each bending portion 63 of the uneven portion. When 64 is formed and vibration occurs, the relative motion of the first and second refrigerant pipes 61 and 62 may be prevented, thereby preventing the occurrence of noise and abrasion.

As described above, the present invention is to increase the efficiency without mounting an accumulator by flowing the refrigerant in the low pressure side flow path of the heat exchanger upwards and the refrigerant in the high pressure side flow path downward to perform heat exchange. In addition, there is an effect that a compact and low-cost refrigerant cycle device can be provided.

In addition, the present invention provides the outlet of the evaporator at a position higher than the inlet of the low pressure side flow path of the heat exchanger, so that even when excess liquid refrigerant is excessively discharged, the refrigerant pipe between the evaporator outlet and the inlet of the low pressure side flow path functions as an accumulator. By doing so, there is an effect that can prevent the liquid refrigerant from flowing into the compressor.

In addition, the present invention has the effect of preventing the noise and wear by reducing the relative movement of the first and second refrigerant pipes even when vibration occurs by forming a contact portion between the first and second refrigerant pipes in a double tube heat exchanger.

Claims (18)

A refrigerant cycle apparatus comprising a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator, The heat exchanger includes a first passage connected to an outlet side of the gas cooler and a second passage connected to an outlet side of the evaporator, wherein the refrigerant of the first passage flows downward and the refrigerant of the second passage upwards. Refrigerant cycle apparatus, characterized in that for performing a heat exchange. The refrigerant cycle apparatus according to claim 1, wherein the outlet of the evaporator is disposed at a position higher than the inlet of the second passage. The refrigerant cycle apparatus according to claim 1, wherein the refrigerant pipe connecting the outlet of the evaporator and the inlet of the second flow passage is inclined downward. The refrigerant cycle apparatus as claimed in claim 1, wherein the heat exchanger is formed of a double tube including a first refrigerant pipe and a second refrigerant pipe surrounding the first refrigerant pipe. The refrigerant cycle apparatus according to claim 4, wherein the first flow passage is formed in the first refrigerant pipe, and the second flow path is formed between the first and second refrigerant pipes. The refrigerant cycle apparatus according to claim 4, wherein the second flow path is formed in the first refrigerant pipe, and the first flow path is formed between the first and second refrigerant pipes. The refrigerant cycle apparatus according to claim 4, wherein a banding part is formed in the middle of the heat exchanger, and a contact part in contact with the first and second refrigerant pipes is formed in the banding part. 8. The refrigerant according to claim 7, wherein the heat exchangers are stacked in a substantially rectangular cross section, and the contact portions are formed at each corner side of the heat exchanger to prevent relative movement between the first and second refrigerant pipes. Cycle device. The refrigerant cycle device of claim 1, wherein the refrigerant cycle device uses carbon dioxide as a refrigerant. A refrigerant cycle apparatus comprising a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator, The heat exchanger includes a first flow passage connected to the outlet side of the gas cooler and a second flow passage connected to the outlet side of the evaporator, the inlet of the first flow passage being provided above the outlet of the first flow passage, The inlet of the second flow path is a refrigerant cycle device, characterized in that provided below the outlet of the second flow path. 11. The method of claim 10 wherein the inlet of the first channel is formed at substantially the same height as the outlet of the second channel, the outlet of the first channel is to be provided at substantially the same height as the inlet of the second channel. Refrigerant cycle device characterized in that. The refrigerant cycle apparatus of claim 10, wherein the refrigerant of the first channel flows downward and the refrigerant of the second channel flows upward. The refrigerant cycle apparatus according to claim 10, wherein the outlet of the evaporator is disposed at a position higher than the inlet of the second passage. The refrigerant cycle apparatus as claimed in claim 10, wherein the refrigerant between the outlet of the evaporator and the second passage flows downward. The method of claim 10, wherein the heat exchanger is provided with a double tube comprising a first refrigerant pipe and a second refrigerant pipe surrounding the first refrigerant pipe, the first flow path is formed in the first refrigerant pipe and the second The flow path is a refrigerant cycle device, characterized in that formed between the first and second refrigerant pipes. 16. The refrigerant cycle apparatus according to claim 15, wherein the first and second refrigerant pipes are formed with at least one contact portion which is in contact with each other to prevent relative movement between the first and second refrigerant pipes. A refrigerant cycle apparatus comprising a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for heat-exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator, The heat exchanger is provided with a double tube and a first refrigerant pipe for flowing the outlet side refrigerant of the gas cooler downward, a second refrigerant pipe surrounding the first refrigerant pipe and flowing the outlet refrigerant of the evaporator upwards, and the first Refrigerant cycle apparatus, characterized in that it comprises at least one contact portion that the 1,2 refrigerant pipes in contact with each other. A refrigerant cycle apparatus comprising a compressor, a gas cooler, a pressure reducing device, an evaporator, and a heat exchanger for heat-exchanging an outlet refrigerant of the gas cooler and an outlet refrigerant of the evaporator, The heat exchanger includes a first refrigerant pipe provided as a double tube for flowing the outlet refrigerant of the gas cooler downward, and a second refrigerant pipe surrounding the first refrigerant pipe and flowing the outlet refrigerant of the evaporator upward. And a refrigerant pipe extending downward from the outlet of the evaporator to connect the second refrigerant pipe.

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