JP6614184B2 - Refrigeration cycle apparatus and heat exchanger - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus and a heat exchanger.

  Conventionally, as this type of refrigeration cycle apparatus, for example, there is one described in Patent Document 1 below. The refrigeration cycle apparatus described in Patent Document 1 includes a gas-liquid separator that separates a refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant, a refrigerant circuit in which the refrigerant circulates, a first-mode refrigerant circuit, and a second-mode refrigerant circuit. And switching means for switching to one of the refrigerant circuit. Specifically, the gas-liquid separator separates the refrigerant flowing out of the outdoor heat exchanger into a gas-phase refrigerant and a liquid-phase refrigerant, causes the gas-phase refrigerant to flow out from the gas-phase refrigerant outlet, and causes the liquid-phase refrigerant to be liquefied. It becomes the structure which can be made to flow out from a phase refrigerant exit. The refrigerant circuit in the first mode is a refrigerant circuit that causes the liquid-phase refrigerant to flow out from the liquid-phase refrigerant outlet of the gas-liquid separator, flow into the second decompression means and the evaporator, and further sucked into the compressor. The refrigerant circuit in the second mode is a refrigerant circuit that causes the gas-phase refrigerant to flow out from the gas-phase refrigerant outlet of the gas-liquid separator and to be sucked into the compressor.

  In the refrigeration cycle apparatus, oil is generally mixed in the refrigerant in order to lubricate the compressor, and most of the oil is mixed in the liquid phase refrigerant. Therefore, when the refrigerant circulates in the second mode refrigerant circuit, when the gas-phase refrigerant returns to the compressor, a part of the liquid-phase refrigerant accumulated in the gas-liquid separator is mixed into the gas-phase refrigerant. The oil is returned to the compressor. This prevents a shortage of oil in the compressor.

JP 2014-149123 A

  The oil return mechanism disclosed in the above prior art has to cope by placing a large-diameter double pipe or a bent pipe inside the gas-liquid separator. The oil return pipe will occupy. For this reason, unless the gas-liquid separator is further increased in size, a space necessary for storing liquid cannot be secured, and a functional component such as a desiccant cannot be disposed inside.

  This invention is made | formed in view of such a subject, The objective is to provide the refrigerating-cycle apparatus and heat exchanger which can implement | achieve a more compact oil return mechanism.

In order to solve the above problems, a refrigeration cycle apparatus according to the present invention includes a liquid reservoir (5) for storing a gas-liquid two-phase refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant to store the liquid-phase refrigerant. A liquid-phase flow path (12, 4, 14) for flowing out the liquid-phase refrigerant from the liquid reservoir, a gas-phase flow path (13a) for flowing out the vapor-phase refrigerant from the liquid reservoir, the liquid-phase flow path, and the A confluence section (13b) where the gas phase flow path merges, a downstream heat exchange section (4) where the liquid-phase refrigerant flowing out of the reservoir flows and exchanges heat with air, and the refrigerant flowing in is exchanged with air. An upstream heat exchanging section (3) for exchanging heat and sending it to the reservoir, wherein the merging section is provided on the upstream side of the compressor, and the liquid phase flow path passes through the downstream heat exchanging section. The average flow area of the liquid phase flow path from the reservoir to the junction is from the reservoir. It is smaller than the average flow area of the gas-phase flow path to the serial merging portion. In addition, an outflow destination switching unit is provided in the liquid phase flow path, and the outflow destination switching unit sets the connection destination of the liquid phase flow path to a pressure reducing valve during cooling operation, and the connection destination of the liquid phase flow path during heating operation. The junction is used.

  According to the present invention, the liquid-phase refrigerant containing oil and the gas-phase refrigerant can be merged and supplied to the compressor at the merge portion. Since the merge portion is provided so as to merge the liquid-phase refrigerant and the gas-phase refrigerant that have flowed out of the reservoir, it is not necessary to provide an additional component such as a conventional double pipe structure in the reservoir. . Since the oil return mechanism can be realized by providing the merging portion in this way, oil can be supplied during the heating operation without increasing the size of the liquid reservoir.

  Reference numerals in parentheses described in “Means for Solving the Problems” and “Claims” indicate a correspondence relationship with “Mode for Carrying Out the Invention” described later, It does not indicate that the invention described in “Means for Solving the Problems” and “Claims” is limited to “Mode for Carrying Out the Invention” described later.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerating cycle apparatus and heat exchanger which can implement | achieve a more compact oil return mechanism can be provided.

FIG. 1 is a heat exchanger according to the first embodiment of the present invention and is a diagram showing a state of cooling operation. FIG. 2 is a heat exchanger according to the first embodiment of the present invention and is a diagram showing a heating operation state. FIG. 3 is a view showing a section taken along the line III-III in FIG. FIG. 4 is a view for explaining the core of the heat exchanger shown in FIG. FIG. 5 is a view showing a heat exchanger according to the second embodiment of the present invention. FIG. 6 is a view showing a heat exchanger according to the third embodiment of the present invention. FIG. 7 is a view showing a heat exchanger according to the fourth embodiment of the present invention. FIG. 8 is a view showing a heat exchanger according to the fifth embodiment of the present invention. FIG. 9 is a view showing a heat exchanger according to the sixth embodiment of the present invention. FIG. 10 is a view showing a heat exchanger according to the seventh embodiment of the present invention. FIG. 11 is a view for explaining the relationship between the refrigerant and the contained oil in the heat exchanger shown in FIG. 1. FIG. 12 is a view showing a heat exchanger according to the eighth embodiment of the present invention. FIG. 13 is a diagram more specifically showing the heat exchanger shown in FIG. 12. 14 is a view showing a XIIII-XIIII cross section of FIG. FIG. 15 is a view showing a cross section XV-XV in FIG. 13. 16 is a view showing a cross section taken along line XVI-XVI of FIG. FIG. 17 is a view showing a cross section XVII-XVII in FIG. 13. 18 is a view showing a cross section XVIII-XVIII in FIG. FIG. 19 is a diagram for explaining an example of a refrigeration cycle to which the heat exchanger according to the embodiment of the present invention is applied. FIG. 20 is a diagram for explaining an example of a refrigeration cycle to which the heat exchanger according to the embodiment of the present invention is applied. FIG. 21 is a diagram for explaining an example of a refrigeration cycle to which the heat exchanger according to the embodiment of the present invention is applied. FIG. 22 is a diagram for explaining an example of the refrigeration cycle to which the heat exchanger according to the embodiment of the present invention is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  The heat exchanger 2 according to the first embodiment will be described with reference to FIG. In this embodiment, the portion such as the core that directly contributes to heat exchange and the portion such as the gas-liquid separator are integrated into a heat exchanger. However, the embodiment of the present invention is not limited to this. It is not something that can be done. The apparatus can be divided for each function, and the whole can be configured as a refrigeration cycle system or a part of a refrigeration cycle system. The heat exchanger 2 is used as an outdoor unit.

  The heat exchanger 2 includes an upstream heat exchange unit 3, a downstream heat exchange unit 4, and a liquid reservoir 5. The upstream heat exchange unit 3 includes two upstream cores 32 and 34 and header tanks 31, 33, and 35. In the present embodiment, an example having two upstream cores 32 and 34 is shown, but the number of cores may be single or three or more. The upstream cores 32 and 34 are portions for exchanging heat between the refrigerant flowing inside and the air flowing outside, and have tubes through which the refrigerant passes and fins provided between the tubes.

  A header tank 31 is attached to the upstream end of the upstream core 32. A header tank 35 is attached to the downstream end of the upstream core 34. A header tank 33 is attached to the downstream end of the upstream core 32 and the upstream end of the upstream core 34 so as to extend over both.

  The header tank 31 is provided with an inflow channel 15. A connection channel 11 is provided in the header tank 35. The refrigerant flowing in from the inflow channel 15 flows into the upstream core 32 from the header tank 31. The refrigerant that has flowed through the upstream core 32 flows into the header tank 33. The refrigerant that has flowed through the header tank 33 flows into the upstream core 34. The refrigerant that has flowed through the upstream core 34 flows into the header tank 35. The refrigerant flowing into the header tank 35 flows out to the connection flow path 11. The connection flow path 11 is connected to the liquid reservoir 5. The refrigerant that has flowed out into the connection channel 11 flows into the storage part 51 of the liquid reservoir 5.

  The liquid reservoir 5 has a storage part 51, a connection channel 11, a connection channel 12, and an outflow channel 13a. The storage unit 51 is a part that separates the gas-liquid two-phase refrigerant flowing from the connection channel 11 into a liquid-phase refrigerant and a gas-phase refrigerant and stores the liquid-phase refrigerant.

  The reservoir 51 is connected to the connection channel 11, the connection channel 12, and the outflow channel 13a. The connection flow path 11 is a flow path that connects the upstream heat exchange unit 3 and the liquid reservoir 5. The connection flow path 12 is a flow path that connects the liquid reservoir 5 and the downstream heat exchange unit 4. The liquid-phase refrigerant that has flowed out of the connection flow path 12 flows into the downstream heat exchange unit 4. The outflow channel 13 a is a channel through which the gas-phase refrigerant flows out from the liquid reservoir 5.

  The downstream heat exchange unit 4 includes a header tank 41, a downstream core 42, a header tank 43, and a bypass flow path 44. An outflow channel 14 is connected to the header tank 41. The header tank 41 is provided at the downstream end of the downstream core 42. A header tank 43 is provided at the upstream end of the downstream core 42. One end of a bypass channel 44 is connected to the header tank 43. The connection channel 12 is connected to the other end of the bypass channel 44.

  The liquid-phase refrigerant flowing into the bypass channel 44 from the connection channel 12 flows in parallel with the downstream core 42 and reaches the header tank 43.

  The liquid phase refrigerant flows from the header tank 43 into the downstream core 42. The downstream core 42 is a portion that exchanges heat between the refrigerant flowing inside and the air flowing outside, and includes a tube through which the refrigerant passes and fins provided between the tubes. Accordingly, the liquid-phase refrigerant that has flowed into the downstream core 42 is directed to the header tank 41 while being supercooled.

  The liquid-phase refrigerant that has flowed into the header tank 41 from the downstream core 42 flows out to the outflow channel 14. The outflow channel 14 is connected to the outflow channel 13a at the junction 13b connected in the middle. An outflow channel 13c is also connected to the junction 13b.

  The outflow channel 14 is connected to an expansion valve that constitutes the refrigeration cycle apparatus, and an evaporator is connected before the expansion valve. The outflow channel 14 is provided with an outflow destination switching unit 21. Since the example shown in FIG. 1 is an example of the cooling operation, the outflow destination switching unit 21 switches so that the liquid-phase refrigerant flowing in the outflow passage 14 flows toward the expansion valve as it is.

  A liquid phase refrigerant adjusting unit 22 is provided between the outflow channel 14 and the merging unit 13b. The liquid-phase refrigerant adjusting unit 22 adjusts the amount of outflow of the liquid-phase refrigerant to the joining portion 13b side by adjusting the interval between the valve body and the valve seat.

  A gas-phase refrigerant adjusting unit 23 is provided on the upstream side of the merging portion 13b of the outflow channel 13a. The gas-phase refrigerant adjustment unit 23 adjusts the amount of the gas-phase refrigerant flowing out to the merge unit 13b by adjusting the interval between the valve body and the valve seat.

  The outflow channel 13c is connected to the merging portion 13b. The outflow passage 13c is connected to the compressor of the refrigeration cycle apparatus.

  FIG. 1 is a diagram schematically showing the heat exchanger 2, but FIG. 3 shows a III-III cross section specifically. As shown in FIG. 3, the liquid reservoir 5 integrally includes a storage part 51 and an outflow channel 14.

  FIG. 2 shows the flow of the refrigerant when the heat exchanger 2 is operated for heating. The outflow destination switching unit 21 is closed during the heating operation. Low pressure refrigerant flows from the inflow passage 15. The low-pressure refrigerant flows through the upstream heat exchange unit 3 to exchange heat and flows into the liquid reservoir 5. The refrigerant is gas-liquid separated in the reservoir 51. The gas-phase refrigerant adjusting unit 23 is opened so as to send the gas-phase refrigerant to the merging unit 13b. The liquid-phase refrigerant that has flowed out of the liquid reservoir 5 flows through the downstream heat exchange section 4 and further undergoes heat exchange, and flows through the outflow passage 14. The liquid refrigerant flowing through the outflow passage 14 contains oil. The liquid-phase refrigerant adjusting unit 22 is adjusted so that the liquid-phase refrigerant containing oil is drawn into the gas-phase refrigerant at the junction 13b. The gas-phase refrigerant and the oil-containing liquid-phase refrigerant that have joined at the junction 13b flow toward the compressor through the outflow passage 13c.

  As described above, when the heat exchanger 2 according to the present embodiment is applied to a refrigeration cycle apparatus, the liquid reservoir 5 that separates gas-liquid two-phase refrigerant into gas-phase refrigerant and liquid-phase refrigerant and stores the liquid-phase refrigerant. A connection flow path 12 as a liquid phase flow path for allowing the liquid phase refrigerant to flow out of the liquid reservoir 5, a downstream heat exchange section 4, an outflow flow path 14, and a gas for causing the gas phase refrigerant to flow out of the liquid storage 5. A refrigeration cycle apparatus comprising an outflow channel 13a as a phase channel, and a merging portion 13b where the liquid phase channel and the gas phase channel merge, and the merging portion 13b is provided on the upstream side of the compressor. Can be provided. If each part is comprised integrally as mentioned above, the heat exchanger 2 which has the same structure can be provided.

  According to this embodiment, the liquid-phase refrigerant containing oil and the gas-phase refrigerant can be merged in the merge section 13b and supplied to the compressor. Since the junction 13b is provided so that the liquid-phase refrigerant and the gas-phase refrigerant that have flowed out of the reservoir 5 are joined, an additional component such as a conventional double pipe structure is provided in the reservoir 5 There is no need. Since the oil return mechanism can be realized by providing the merging portion 13b in this way, oil supply during the heating operation can be performed without increasing the size of the liquid reservoir 5.

  Further, the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment include the downstream heat exchange section 4 that allows the liquid-phase refrigerant flowing out of the reservoir 5 to flow in and exchange heat with air, and the liquid-phase flow path is on the downstream side. It is configured so as to reach the junction 13b after passing through the heat exchange unit 4. As shown in FIG. 11, when the liquid phase refrigerant is heat-exchanged in the downstream heat exchange section 4, the liquid phase refrigerant 51 is gradually scattered from the state where the oil 52 is scattered as shown in FIG. 11C. The state transition to the phase refrigerant 53 causes the content ratio of the oil 52 to the liquid phase refrigerant 51 to increase, as shown in FIG. 11B through FIG. If it does in this way, the return of the liquid-phase refrigerant | coolant in the junction part 13b can be decreased, and the performance fall as a refrigerating cycle can be reduced.

  Further, the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment further include an upstream heat exchange unit 3 that exchanges heat of the flowing refrigerant with air and sends the refrigerant to the reservoir. Since the upstream heat exchanging unit 3 and the downstream heat exchanging unit 4 are provided and the refrigerant can flow through both of them during heating, the performance as an evaporator can be improved.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, when the refrigerant having the same refrigerant density and the same refrigerant flow rate is flowed, than the pressure loss of the flow path from the reservoir 5 to the merge portion 13b, The pressure loss of the flow path from the liquid reservoir 5 to the merging portion 13b is reduced. More specifically, the average flow path area of the liquid phase flow path from the reservoir 5 to the merge section 13b is made smaller than the average flow path area of the gas phase flow path from the reservoir 5 to the merge section 13b. ing. By comprising in this way, the return amount of a refrigerant | coolant can be ensured and the lack of the oil return amount can be avoided.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, the outflow destination switching unit 21 is further provided in the liquid phase flow path, and the outflow destination switching unit 21 is in the liquid phase during the cooling operation as shown in FIG. The connection destination of the flow path is a pressure reducing valve of the refrigeration cycle, and the connection destination of the liquid phase flow path is a gas phase flow path during heating operation as shown in FIG. By switching the outflow destination switching unit 21, the cooling operation and the heating operation can be switched.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, the liquid-phase refrigerant adjustment unit 22 is further provided in the liquid-phase flow channel upstream of the junction unit 13b. The liquid phase refrigerant adjusting unit 22 adjusts the flow rate of the refrigerant flowing through the liquid phase flow path. In particular, during the heating operation as shown in FIG. 2, it is possible to adjust so that the liquid-phase refrigerant containing oil is drawn to the joining portion 13 b side.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, the gas-phase refrigerant adjusting unit 23 is further provided in the gas-phase flow channel on the upstream side of the merging unit 13b. The gas phase refrigerant adjusting unit 23 adjusts the flow rate of the refrigerant flowing through the gas phase flow path. In particular, during the heating operation as shown in FIG. 2, it is possible to adjust so that the liquid-phase refrigerant containing oil is drawn to the joining portion 13 b side.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, the upstream heat exchange unit 3 that exchanges heat between the refrigerant passing through the interior and the air, and the gas-liquid two-phase refrigerant that has flowed out of the upstream heat exchange unit 3 Is stored in a gas phase and a liquid phase refrigerant to store the liquid phase refrigerant, and a connection channel 12 as a liquid phase channel for flowing the liquid phase refrigerant out of the liquid reservoir 5, downstream heat An exchanging unit 4, an outflow channel 14, an outflow channel 13 a as a gas phase channel for allowing the gas phase refrigerant to flow out of the reservoir 5, and a confluence unit 13 b where the liquid phase channel and the gas phase channel merge. It is equipped with.

  Further, in the refrigeration cycle apparatus and the heat exchanger 2 according to the present embodiment, the liquid phase flow path is configured so as to reach the junction part 13b after passing through the downstream heat exchange part 4.

  In the heat exchanger 2 according to this embodiment, the liquid reservoir 5 and the merging portion 13 b are provided on the same side with respect to the upstream heat exchanging portion 3. By providing the liquid reservoir 5 and the merging portion 13b on the same side, the pipes can be consolidated.

  In the heat exchanger 2 according to the present embodiment, the liquid refrigerant outlet 511 from which the liquid phase refrigerant flows out from the liquid reservoir 5 and the outlet 411 from which the liquid phase refrigerant flows out from the downstream heat exchanging section 4 are arranged on the downstream side. The heat exchange unit 4 is provided on the same side. By providing the liquid refrigerant outlet 511 and the outlet 411 on the same side, the pipes can be integrated. Furthermore, by providing the refrigerant inlet 512 through which the refrigerant flows from the upstream heat exchange unit 3 on the same side, the pipes can be further consolidated.

  In the refrigeration cycle and heat exchanger 2 according to the present embodiment, the downstream heat exchange unit 4 includes a downstream core 42 and a bypass flow path 44, and the flow of tubes constituting the downstream core 42 The road cross-sectional area and the flow path cross-sectional area of the bypass flow path 44 are configured to be different. The liquid refrigerant flowing out of the liquid reservoir 5 passes through the bypass channel 44 and is conveyed to the opposite side of the downstream heat exchange unit 4. Accordingly, the liquid-phase refrigerant is supplied to the opposite side of the downstream core 42 and can return to the reservoir 5 side while exchanging heat.

  In the refrigeration cycle and heat exchanger 2 according to the present embodiment, as shown in FIG. 4, an upstream fin 322 included in the upstream heat exchange unit 3 and a downstream fin 422 included in the downstream heat exchange unit 4. The shapes are different from each other. As shown in FIG. 4A, the upstream core 32 is provided with upstream fins 322 having a fin pitch P <b> 1 between a plurality of tubes 321. As shown in FIG. 4B, the downstream core 42 is provided with downstream fins 422 having a fin pitch P <b> 2 between a plurality of tubes 421. Since fin pitch P <b> 1 <fin pitch P <b> 2, the shapes are different from each other, and the heat transfer coefficient of the downstream fin 422 is smaller than the heat transfer coefficient of the upstream fin 322.

  A heat exchanger 2A according to the second embodiment will be described with reference to FIG. In the heat exchanger 2 </ b> A, a cooling side outflow channel 14 </ b> A is connected to the header tank 43. From the reservoir 5, a connection flow path 12Ab toward the downstream heat exchange section 4A and a connection flow path 12Aa toward the junction section 13b extend. When the outflow destination switching unit 21 is closed during heating, the liquid-phase refrigerant inside the liquid reservoir 5 does not flow through the downstream heat exchange unit 4A but flows into the junction unit 13b via the connection channel 12Aa.

  A heat exchanger 2B according to the third embodiment will be described with reference to FIG. In the heat exchanger 2 </ b> B, the outflow passage 14 </ b> B is connected to the header tank 43. The outflow channel 14B is a channel connected to the expansion valve, and an outflow destination switching unit 21 is provided. The outflow channel 14B branches on the upstream side of the outflow destination switching unit 21 and is connected to the merging unit 13b. In the merging portion 13b, the outflow channel 13a and the outflow channel 14B merge. A liquid-phase refrigerant adjusting unit 22 is provided on the upstream side of the merging portion 13b of the outflow channel 14B. A gas phase refrigerant adjusting unit 23 is provided in the outflow channel 13a. The liquid reservoir 5 and the header tank 41 are connected by a connection flow path 12Ab.

  The heat exchanger 2C according to the fourth embodiment will be described with reference to FIG. In the heat exchanger 2 </ b> C, the outflow channel 14 </ b> C connected to the header tank 43 is connected to the junction 13 b, but the outflow destination switching unit 21 is provided in the vicinity of the header tank 43.

  A heat exchanger 2D according to the fifth embodiment will be described with reference to FIG. The heat exchanger 2D includes an upstream heat exchange unit 3D, a downstream heat exchange unit 4D, and a liquid reservoir 5. The upstream heat exchange unit 3D includes a header tank 31D, an upstream core 32D, and a header tank 33D. The downstream heat exchange unit 4D includes a header tank 41D, a downstream core 42D, and a header tank 43D. The liquid reservoir 5 is disposed between the upstream heat exchange unit 3D and the downstream heat exchange unit 4D. The header tank 31 </ b> D and the liquid reservoir 5 are connected by a connection channel 11. The liquid reservoir 5 and the header tank 41D are connected by a connection channel 12Da. The header tank 43D and the merging portion 13b are connected by an outflow channel 12Db. The outflow channel 12Db is branched from the channel connected to the expansion valve, and an outflow destination switching unit 21 is provided.

  The heat exchanger 2E according to the sixth embodiment will be described with reference to FIG. The heat exchanger 2E includes an upstream heat exchange unit 3E, a downstream heat exchange unit 4E, and a liquid reservoir 5. The upstream heat exchange unit 3E includes a header tank 31E, an upstream core 32E, and a header tank 33E. The downstream heat exchange unit 4E includes a header tank 41E, a downstream core 42E, and a header tank 43E.

  The header tank 31 </ b> E and the header tank 41 </ b> E are arranged side by side on one end side of the liquid reservoir 5. The header tank 33E and the header tank 43E are arranged side by side on the other end side of the liquid reservoir 5. The refrigerant that has flowed into the header tank 31E flows into the header tank 33E along the longitudinal direction of the liquid reservoir 5. The header tank 33E joins the outflow passage 13aE provided above the reservoir 5 at the joining portion 13bE. The liquid phase refrigerant that has flowed out from below the liquid reservoir 5 flows directly into the header tank 41E. The refrigerant flowing into the header tank 41E flows toward the header tank 43E along the longitudinal direction of the liquid reservoir 5.

  A heat exchanger 2F according to the seventh embodiment will be described with reference to FIG. The heat exchanger 2F includes an upstream heat exchange unit 3F, a downstream heat exchange unit 4F, and a liquid reservoir 5F. The upstream heat exchange unit 3F includes a header tank 31F, an upstream core 32F, and a header tank 33F. The downstream heat exchange unit 4F includes a header tank 41F, a downstream core 42F, and a header tank 43F. The reservoir 5F is disposed so as to straddle the upstream heat exchange unit 3F and the downstream heat exchange unit 4F.

  Next, a heat exchanger according to the eighth embodiment will be described with reference to FIG. The heat exchanger according to the eighth embodiment includes an upstream heat exchange unit 3G, a downstream heat exchange unit 4G, and a liquid reservoir 5G. A refrigerant adjustment unit 6G including a switching valve is disposed in the upper part of the liquid reservoir 5G. The refrigerant that has flowed out of the compressor passes through the refrigerant adjustment unit 6G, and flows into the upstream heat exchange unit 3G through the inflow channel 15G. The refrigerant cooled through the upstream heat exchange unit 3G flows into the storage unit 51G through the connection channel 11G. The refrigerant that has become a liquid phase in the reservoir 51G flows out to the downstream heat exchange unit 4G through the connection flow path 12G. The liquid-phase refrigerant that has passed through the downstream heat exchange section 4G flows into the refrigerant adjustment section 6G through the liquid refrigerant flow path 14G, and returns to the refrigeration cycle.

  In the present embodiment, in addition to the refrigerant adjustment unit 6G, the liquid refrigerant flow path 14G is also configured integrally with the liquid reservoir 5G. A description will be added with reference to FIGS. FIG. 13A is a plan view of a heat exchanger 2G according to the eighth embodiment, and FIG. 13B is a front view of the heat exchanger 2G.

  As described above, the refrigerant that has flowed out of the compressor passes through the refrigerant adjustment unit 6G, and flows into the upstream heat exchange unit 3G through the inflow channel 15G. FIG. 14 shows a cross section XIIII-XIIII of the inflow channel 15G.

  The refrigerant cooled through the upstream heat exchange unit 3G flows into the storage unit 51G through the connection channel 11G. FIG. 15 shows a cross section XV-XV of the connection channel 11G. As shown in FIG. 15, an auxiliary liquid storage part 51Ga is provided so as to be connected to the connection channel 11G.

  The refrigerant that has become a liquid phase in the reservoir 51G flows out to the downstream heat exchange unit 4G through the connection flow path 12G. FIG. 16 shows a cross section XVI-XVI of the connection channel 12G.

  The liquid-phase refrigerant that has passed through the downstream heat exchange unit 4G flows into the refrigerant adjustment unit 6G through the liquid refrigerant channel 14G. FIG. 17 shows a cross section XVII-XVII of a portion from the downstream heat exchange section 4G to the liquid refrigerant flow path 14G. A partition plate 14Gb is provided so as to partition the liquid refrigerant channel 14G and the connection channel 12G. A partition plate 14Ga is provided so as to partition the cross section XVIII-XVIII of the portion from the liquid refrigerant flow path 14G to the refrigerant adjustment section 6G into the liquid refrigerant flow path 14G and the inflow flow path 15G shown in FIG.

  An example of a refrigeration cycle to which the liquid reservoir 5 of the present embodiment is applied will be described with reference to FIG. As shown in FIG. 19, the refrigeration cycle apparatus 71 is applied to the vehicle air conditioner 7. The vehicle air conditioner 7 is a device that adjusts the temperature of the vehicle interior by adjusting the temperature of the blown air that is blown into the vehicle interior that is the air-conditioning target space. The vehicle air conditioner 7 includes a refrigeration cycle device 71, a coolant circulation circuit 72, and an air conditioning unit 73.

  The refrigeration cycle apparatus 71 can be selectively switched between a cooling mode for cooling the vehicle interior by cooling the blown air and a heating mode for heating the vehicle interior by heating the blown air. The refrigeration cycle apparatus 71 is a vapor compression refrigeration cycle apparatus including a heat pump circuit in which refrigerant circulates.

  The refrigeration cycle apparatus 71 includes a compressor 711, a water-cooled condenser 712, a pressure adjusting unit 60, a heat exchanger 2, a flow rate adjusting valve 607a, a flow rate adjusting valve 604a, a decompressor 713, and an evaporator 714. As the refrigerant circulating in the refrigeration cycle apparatus 71, for example, an HFC refrigerant or an HFO refrigerant can be used. Oil for lubricating the compressor 711, that is, refrigeration oil is mixed in the refrigerant. Therefore, a part of the refrigerating machine oil circulates through the refrigeration cycle apparatus 71 together with the refrigerant.

  The compressor 711 sucks and compresses the refrigerant from the suction port in the refrigeration cycle apparatus 71, and discharges the refrigerant that has been overheated by the compression from the discharge port. The compressor 711 is an electric compressor. The refrigerant discharged from the discharge port flows to the water-cooled condenser 712.

  The water-cooled condenser 712 is a well-known water refrigerant heat exchanger. The water-cooled condenser 712 has a first heat exchange unit 712a and a second heat exchange unit 712b.

  The first heat exchange unit 712 a is provided between the discharge port of the compressor 711 and the pressure adjustment unit 60. That is, the refrigerant discharged from the compressor 711 flows through the first heat exchange unit 712a.

  The second heat exchange unit 712b is provided in the middle of the coolant circulation circuit 72 through which the engine coolant flows. In the cooling water circulation circuit 72, the cooling water is circulated by the cooling pump 81. The cooling water circulates in the order of the second heat exchange unit 712b, the heater core 80, the cooling pump 81, and the engine 82.

  The water-cooled condenser 712 heats the cooling water with the heat of the refrigerant by exchanging heat between the refrigerant flowing in the first heat exchange unit 712a and the cooling water flowing in the second heat exchange unit 712b. Cool down. The refrigerant that has flowed out of the first heat exchange unit 712a flows to the pressure adjustment unit 60.

  In the coolant circulation circuit 72, the refrigerant heated in the engine 82 and the second heat exchange unit 712b flows through the heater core 80, whereby the heater core 80 is heated. The heater core 80 is disposed in the casing 731 of the air conditioning unit 73. The heater core 80 heats the blown air by performing heat exchange between the cooling water flowing through the heater core 80 and the blown air flowing through the casing 731. The water-cooled condenser 712 functions as a heat radiator that indirectly dissipates heat from the refrigerant discharged from the compressor 711 and flowing into the first heat exchange unit 712 a to the blown air indirectly through the cooling water and the heater core 80.

  The pressure adjustment unit 60 includes a fixed throttle 601, a bypass channel 602, and an on-off valve 603. The pressure adjustment unit 60 includes an upstream heat exchange unit that enables switching between a heating mode in which the refrigerant absorbs heat from the outside air and a cooling mode in which the refrigerant radiates heat to the outside air in the upstream heat exchange unit 3 of the heat exchanger 2. This corresponds to a pressure adjustment unit that adjusts the pressure of the refrigerant flowing into the refrigerant.

  The fixed throttle 601 decompresses and discharges the refrigerant that has flowed out of the first heat exchange unit 712a of the water-cooled condenser 712. As the fixed throttle 601, a nozzle or an orifice with a fixed throttle opening can be used. The refrigerant discharged from the fixed throttle 601 flows to the heat exchanger 2.

  The bypass channel 602 is a refrigerant channel that guides the refrigerant that has flowed out of the first heat exchange unit 712a to the heat exchanger 2 by bypassing the fixed throttle 601. The on-off valve 603 is an electromagnetic valve that opens and closes the bypass channel 602.

  In the pressure adjustment unit 60, the on-off valve 603 is closed during the heating mode. Thereby, at the time of heating mode, the refrigerant | coolant which flowed out from the 1st heat exchange part 712a of the water-cooled condenser 712 is pressure-reduced by flowing through the fixed aperture 601, and flows into the heat exchanger 2. On the other hand, the on-off valve 603 is fully opened during the cooling mode. Thus, in the cooling mode, the refrigerant that has flowed out of the first heat exchange unit 712a of the water-cooled condenser 712 bypasses the fixed throttle 601 and flows through the bypass flow path 602. That is, the refrigerant that has flowed out of the first heat exchange unit 712a of the water-cooled condenser 712 flows to the heat exchanger 2 without being depressurized.

  The heat exchanger 2 is an outdoor heat exchanger disposed on the vehicle front side in the engine room. The heat exchanger 2 includes an upstream heat exchange unit 3, a liquid reservoir 5, and a downstream heat exchange unit 4.

  The refrigerant that has flowed out of the pressure adjustment unit 60 flows into the upstream heat exchange unit 3. The upstream heat exchange unit 3 is a part that performs heat exchange between the refrigerant flowing in and outside air that is air outside the vehicle compartment that is blown by a blower fan (not shown). In the heating mode, the upstream heat exchange unit 3 functions as an evaporator that evaporates the refrigerant by exchanging heat between the refrigerant flowing in and outside air. Further, in the cooling mode, the upstream heat exchange unit 3 functions as a condenser that cools the refrigerant by exchanging heat between the flowing refrigerant and the outside air.

  The liquid reservoir 5 separates the refrigerant that has flowed out of the upstream heat exchange unit 3 into a gas phase refrigerant and a liquid phase refrigerant, causes the gas phase refrigerant and the liquid phase refrigerant to flow out separately, and stores the liquid phase refrigerant. It is possible. The liquid reservoir 5 discharges the separated gas-phase refrigerant toward the flow path 16 for the compressor, and discharges the separated liquid-phase refrigerant toward the connection flow path 12.

  The compressor flow path 16 is connected to an intermediate portion of the refrigerant flow path 715. The refrigerant channel 715 is a channel that guides the refrigerant that has flowed out of the decompressor 713 to the suction port of the compressor 711. The compressor-bound flow path 16 is a flow path that guides the gas-phase refrigerant discharged from the liquid reservoir 5 to the compressor 711 by bypassing the decompressor 713.

  The liquid-phase refrigerant discharged from the liquid-phase refrigerant outlet of the reservoir 5 flows into the downstream heat exchange unit 4. The downstream heat exchange unit 4 is a part that further increases the heat exchange efficiency of the refrigerant in the heat exchanger 2 by exchanging heat between the inflowing liquid-phase refrigerant and the outside air. Specifically, in the heating mode, the downstream heat exchange unit 4 evaporates the liquid refrigerant by performing heat exchange between the flowing liquid refrigerant and the outside air. Thereby, since the liquid-phase refrigerant | coolant which remained without being able to evaporate in the upstream heat exchange part 3 can be evaporated, the function as an evaporator in the heat exchanger 2 is improved. Further, in the cooling mode, the downstream heat exchange unit 4 functions as a subcooler that further cools the liquid phase refrigerant by exchanging heat between the inflowing liquid phase refrigerant and the outside air. Thereby, the function as a condenser in the heat exchanger 2 is improved.

  The downstream heat exchange unit 4 is connected to the flow rate adjustment valve 607a via the outflow channel 14. The refrigerant that has flowed out of the downstream heat exchange unit 4 flows into the flow rate adjustment valve 607a through the outflow channel 14.

  The flow rate adjustment valve 607a is connected to the decompressor 713 via the outflow channel 14. The flow rate adjustment valve 607 a adjusts the amount of refrigerant flowing from the downstream heat exchange unit 4 via the outflow passage 14 to the decompressor 713.

  The refrigerant that has flowed out of the downstream heat exchange unit 4 flows into the decompressor 713 through the outflow channel 14. The decompressor 713 decompresses and discharges the inflowing refrigerant. The refrigerant decompressed by the decompressor 713 flows into the evaporator 714. In addition, the refrigerant discharged from the evaporator 714 flows into the decompressor 713. The decompressor 713 is a temperature-sensitive mechanical expansion that decompresses and expands the refrigerant flowing into the evaporator 714 by a mechanical mechanism so that the degree of superheat of the refrigerant discharged from the evaporator 714 falls within a predetermined range. It is a valve.

  The refrigerant discharged from the decompressor 713 flows into the evaporator 714. The evaporator 714 is a heat exchanger that cools the blown air by performing heat exchange between the refrigerant flowing inside and the blown air flowing inside the casing 731 of the air conditioning unit 73 in the cooling mode. In the evaporator 714, heat exchange is performed between the blown air and the refrigerant, whereby the refrigerant evaporates. The evaporated refrigerant is discharged from the evaporator 714 and flows into the suction port of the compressor 711 through the decompressor 713 and the refrigerant flow path 715.

  The flow rate adjustment valve 604a is provided in the middle of the compressor flow path 16. The flow rate adjustment valve 604a is an electromagnetic valve that can change the cross-sectional area of the flow passage 16 for the compressor by adjusting the opening degree. By adjusting the opening degree of the flow rate adjusting valve 604a, it is possible to adjust the flow rate of the refrigerant flowing through the compressor flow path 16.

  In the refrigeration cycle apparatus 71, the pressure adjustment unit 60, the flow rate adjustment valve 607 a, and the flow rate adjustment valve 604 a are integrally configured as one actuator device, which is the refrigerant adjustment unit 6.

  The air conditioning unit 73 includes a casing 731 and a ventilation passage switching door 732. In the casing 731, air is flowing. Inside the casing 731, an evaporator 714 and a heater core 80 are sequentially arranged from the upstream side to the downstream side in the flow direction of the blown air. The evaporator 714 cools the blown air by exchanging heat between the refrigerant flowing inside and the blown air. On the downstream side of the evaporator 714 in the casing 731, a hot air passage where the heater core 80 is disposed and a cold air passage where the heater core 80 is not disposed are provided.

  The air passage switching door 732 is shown as a first door position indicated by a solid line in the drawing that closes the cold air passage while opening the hot air passage, and a broken line in the drawing that closes the hot air passage and opens the cold air passage. The second door position is configured to be displaceable. On the downstream side of the hot air passage and the cold air passage in the air flow direction of the casing 731, a plurality of openings (not shown) that open into the vehicle compartment are formed.

  In the air conditioning unit 73, the air passage switching door 732 is positioned at the first door position indicated by a solid line in the heating mode. Thus, since the blown air that has passed through the evaporator 714 passes through the warm air passage, the blown air is heated by the heater core 80 and flows downstream. On the other hand, in the cooling mode, the air passage switching door 732 is positioned at the second door position indicated by a broken line. Thereby, since the blown air that has passed through the evaporator 714 passes through the cool air passage, the blown air cooled by the evaporator 714 flows downstream as it is.

  Next, another example of the refrigeration cycle to which the liquid reservoir 5 of the present embodiment is applied will be described with reference to FIG. As shown in FIG. 20, the refrigeration cycle apparatus 71A is applied to a vehicle air conditioner 7A. The vehicle air conditioner 7A includes a refrigeration cycle device 71A, a cooling water circulation circuit 72, and an air conditioning unit 73. Since the cooling water circulation circuit 72 and the air conditioning unit 73 are the same as the vehicle air conditioner 7, the description thereof is omitted.

  The refrigeration cycle apparatus 71A includes a refrigerant adjustment unit 6A instead of the refrigerant adjustment unit 6 of the refrigeration cycle apparatus 71.

  The refrigeration cycle apparatus 71A includes a compressor 711, a water-cooled condenser 712, a pressure adjusting unit 60, a heat exchanger 2, a three-way valve 607b, a flow rate adjusting valve 604b, a decompressor 713, and an evaporator 714.

  The compressor flow path 16 is connected to an intermediate portion of the refrigerant flow path 715. The refrigerant channel 715 is a channel that guides the refrigerant that has flowed out of the decompressor 713 to the suction port of the compressor 711. The compressor-bound channel 16 is a channel that guides the gas-phase refrigerant discharged from the reservoir 5 to the compressor 711 by bypassing the three-way valve 607 b and the decompressor 713.

  The downstream heat exchange unit 4 is connected to the three-way valve 607b via the outflow channel 14. The refrigerant that has flowed out of the downstream heat exchange section 4 flows into the three-way valve 607b through the outflow passage 14.

  The three-way valve 607 b is connected to the decompressor 713 via the outflow passage 14 and is connected to a midway portion of the compressor going passage 16 via the bypass passage 606. The three-way valve 607b selectively switches whether the refrigerant flowing from the downstream heat exchange unit 4 via the outflow channel 14 is caused to flow to the decompressor 713 or the bypass channel 606.

  The flow rate adjusting valve 604b is provided in the middle part of the flow path 16 for the compressor. The flow rate adjustment valve 604 b is provided on the upstream side of the connection portion between the compressor flow path 16 and the bypass flow path 606. The flow rate adjustment valve 604b is an electromagnetic valve that can change the flow path cross-sectional area of the flow path 16 for the compressor by adjusting the opening degree. By adjusting the opening degree of the flow rate adjusting valve 604b, it is possible to adjust the flow rate of the refrigerant flowing through the compressor flow path 16.

  In the refrigeration cycle device 71, the pressure adjustment unit 60, the three-way valve 607 b, and the flow rate adjustment valve 604 b are integrally configured as one actuator device, which is the refrigerant adjustment unit 6.

  Next, another example of the refrigeration cycle to which the liquid reservoir 5 of the present embodiment is applied will be described with reference to FIG. As shown in FIG. 21, the refrigeration cycle apparatus 71B is applied to a vehicle air conditioner 7B. The vehicle air conditioner 7B includes a refrigeration cycle device 71B, a cooling water circulation circuit 72, and an air conditioning unit 73. Since the cooling water circulation circuit 72 and the air conditioning unit 73 are the same as the vehicle air conditioner 7, the description thereof is omitted.

  In the refrigeration cycle apparatus 71B, an accumulator 716 is provided on the upstream side of the compressor 711 in the refrigerant flow path 715. Thus, in addition to the liquid reservoir 5, an accumulator 716 may be provided as a second liquid storage mechanism.

  Next, another example of the refrigeration cycle to which the liquid reservoir 5 of the present embodiment is applied will be described with reference to FIG. As shown in FIG. 22, the refrigeration cycle apparatus 71C is applied to a vehicle air conditioner 7C. The vehicle air conditioner 7C includes a refrigeration cycle device 71C, a cooling water circulation circuit 72, and an air conditioning unit 73. Since the cooling water circulation circuit 72 and the air conditioning unit 73 are the same as the vehicle air conditioner 7, the description thereof is omitted.

  In the refrigeration cycle apparatus 71 </ b> C, a receiver 717 is provided on the downstream side of the water-cooled condenser 712. Thus, in addition to the liquid reservoir 5, a receiver 717 may be provided as a second liquid storage mechanism.

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. Those in which those skilled in the art appropriately modify the design of these specific examples are also included in the scope of the present invention as long as they have the features of the present invention. Each element included in each of the specific examples described above and their arrangement, conditions, shape, and the like are not limited to those illustrated, and can be changed as appropriate. Each element included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

5: Liquid storage device 12: Connection channel 14: Outflow channel 13a: Outflow channel 13b: Junction section

Claims (3)

A refrigeration cycle apparatus,
A liquid reservoir (5) for separating the gas-liquid two-phase refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and storing the liquid-phase refrigerant;
A liquid phase flow path (12, 4, 14) for flowing a liquid phase refrigerant out of the liquid reservoir;
A gas phase flow path (13a) for allowing a gas phase refrigerant to flow out of the liquid reservoir;
A junction (13b) where the liquid phase channel and the gas phase channel merge;
A downstream heat exchange section (4) for allowing the liquid phase refrigerant flowing out of the reservoir to flow in and exchange heat with air;
An upstream heat exchange section (3) for exchanging heat of the flowing refrigerant with air and sending it to the reservoir,
The junction is provided on the upstream side of the compressor,
The liquid phase flow path passes through the downstream heat exchange section and then reaches the joining section,
The average flow path area of the liquid phase flow path from the reservoir to the merge section is smaller than the average flow path area of the gas phase flow path from the reservoir to the merge section ,
In addition, an outflow destination switching unit is provided in the liquid phase flow path,
The effluent destination switching unit is a refrigeration cycle apparatus in which the connection destination of the liquid phase flow path is a pressure reducing valve during a cooling operation, and the connection destination of the liquid phase flow path is the merging portion during a heating operation . The refrigeration cycle apparatus according to claim 1,
Furthermore, a liquid phase refrigerant adjusting part (22) is provided in the liquid phase flow path upstream of the merging part,
The liquid phase refrigerant adjustment unit is a refrigeration cycle apparatus that adjusts a flow rate of refrigerant flowing through the liquid phase flow path. The refrigeration cycle apparatus according to claim 1,
Furthermore, a gas-phase refrigerant adjustment part (23) is provided in the gas-phase flow path upstream of the merging part,
The gas phase refrigerant adjustment unit is a refrigeration cycle apparatus that adjusts a flow rate of a refrigerant flowing through the gas phase flow path.

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