JPWO2014068687A1 - Parallel flow heat exchanger and air conditioner using the same - Google Patents

Abstract

It is an object of the present invention to provide a parallel flow type heat exchanger that has a simple structure and induces a swirling flow in a header pipe to evenly distribute the refrigerant to each flat pipe. The parallel flow heat exchanger according to the present invention includes a first header pipe and a second header pipe, a plurality of flat tubes connecting the first header pipe and the second header pipe, and a refrigerant flowing into the first header pipe. An inflow pipe connected to the second header pipe and an outflow pipe through which the refrigerant flows out, and the inflow pipe is disposed so that the central axis of the inflow pipe is offset from the central axis of the first header pipe.

Description

  The present invention relates to a parallel flow heat exchanger and air-conditioning air using the same.

  Parallel flow type heat exchangers that have a plurality of flat tubes between two header tubes and exchange heat with the refrigerant flow in the flat tubes are widely used in automotive radiators and air conditioners for cooling. Yes.

  In order to efficiently perform heat exchange with the parallel flow heat exchanger, it is necessary to evenly distribute the refrigerant to the flat tubes in the header tube. However, particularly when the refrigerant is a gas-liquid two-phase flow, the header pipe has a complicated flow field and is difficult to distribute evenly. For example, the pressure distribution varies as the flow collides with a flat tube protruding into the header tube. In addition, when the flow form in the header pipe is a laminar flow, the height of the refrigerant gas-liquid interface varies. Due to these phenomena, the refrigerant distribution amount to each flat tube is biased. As a result, the performance of the heat exchanger decreases.

  On the other hand, in Patent Document 1, in order to “split the heat transfer tubes uniformly, increase the effective heat transfer area where the refrigerant actually evaporates, and improve performance” "Sequentially slow down from the header on the side to the header on the downstream side," "Sequentially increase the spiral angle of the spiral groove provided in the header from the header on the upstream side to the header on the downstream side," Disclosed is a heat exchanger in which the groove depth is sequentially reduced from the upstream header to the downstream header.

  However, in the spiral groove provided in the header of the heat exchanger disclosed in Patent Document 1, there is a possibility that the swirl flow for allowing the refrigerant to be evenly divided into the heat transfer tubes is insufficient.

JP-A-5-223490

  An object of the present invention is to provide a parallel flow heat exchanger that has a simple structure, induces a swirling flow in a header pipe, and evenly distributes the refrigerant to each flat pipe.

  The parallel flow heat exchanger according to the present invention includes a first header pipe and a second header pipe, a plurality of flat tubes connecting the first header pipe and the second header pipe, and a refrigerant flowing into the first header pipe. An inflow pipe connected to the second header pipe and an outflow pipe through which the refrigerant flows out, and the inflow pipe is disposed so that the central axis of the inflow pipe is offset from the central axis of the first header pipe.

  According to the present invention, it is possible to provide a parallel flow type heat exchanger that induces a swirling flow in a header pipe with a simple structure and distributes the refrigerant evenly to each flat pipe.

The figure which shows the conventional parallel flow type heat exchanger. The figure which shows the parallel flow type heat exchanger in Example 1. FIG. The figure which shows the rotation induction structure by the inflow tube in Example 1. FIG. The figure which shows the refrigerant | coolant flow field in the header pipe | tube in FIG. The figure which shows the refrigerant | coolant flow field in the header pipe | tube in Example 1. FIG. 3 is a three-dimensional view of a parallel flow heat exchanger according to Embodiment 2. FIG. The figure which shows the connection relation of the inflow pipe | tube and header pipe | tube in Example 2. FIG. The figure which shows the connection relation of the inflow pipe | tube and header pipe | tube in Example 2. FIG. The figure which shows the parallel flow type heat exchanger in Example 3. FIG. The figure which shows the parallel flow type heat exchanger in Example 3. FIG. FIG. 10 is a diagram showing a header pipe in the fourth embodiment. The figure which shows the swirling flow guide plate in Example 4. The figure which shows the parallel flow type heat exchanger in Example 5. FIG. The refrigeration cycle block diagram of a domestic air conditioner. The block diagram of the refrigerating cycle at the time of employ | adopting a reheat dehumidification system.

  The parallel flow type heat exchanger of the present embodiment includes a first header pipe and a second header pipe, a plurality of flat tubes connecting the first header pipe and the second header pipe, and a refrigerant connected to the first header pipe. An inflow pipe that flows in and an outflow pipe that is connected to the second header pipe and from which the refrigerant flows out, and the inflow pipe is disposed so that the central axis of the inflow pipe is offset from the central axis of the first header pipe . According to the present embodiment, it is possible to provide a parallel flow type heat exchanger that induces a stronger swirling flow in the header pipe with a simple structure and distributes the refrigerant more evenly to each flat pipe.

  Hereinafter, the parallel flow type heat exchanger according to the first embodiment will be described with reference to the drawings. First, a refrigeration cycle to which the parallel flow heat exchanger of the present embodiment is applied will be described. FIG. 14 is a diagram illustrating a configuration of a refrigeration cycle of a home air conditioner. In FIG. 14, 101 is a compressor, 102 is a four-way valve, 103 is a throttle device such as an electric valve, 104 is an outdoor heat exchanger, and 106 is an indoor heat exchanger.

  In the air conditioner, by switching the four-way valve 102, cooling operation (solid arrow) using the outdoor heat exchanger 104 as an evaporator and the indoor heat exchanger 106 as a condenser, and the outdoor heat exchanger 104 as a condenser and indoor heat A heating operation (broken arrows) using the exchanger 106 as an evaporator can be performed. For example, in the cooling operation, the high-temperature and high-pressure refrigerant compressed by the compressor 101 passes through the four-way valve 102 and flows into the outdoor heat exchanger 104, and dissipates heat and condenses by heat exchange with air. Then, after performing the same enthalpy expansion by the expansion device 103 such as an electric valve, it becomes a gas-liquid two-phase flow in which gas and liquid are mixed at low temperature and low pressure and flows into the indoor heat exchanger 106. In the indoor heat exchanger 104, the refrigerant is vaporized into a gas refrigerant from the inlet to the outlet by the heat absorption action from the air through the fins attached to the refrigerant pipe and the refrigerant pipe. And the refrigerant | coolant which came out of the indoor heat exchanger 106 returns to the compressor 101, and comprises a cycle. In general, the outdoor heat exchanger 104 and the outdoor heat exchanger 106 require a piping structure that branches from one refrigerant pipe to a plurality of refrigerant pipes in order to perform heat exchange efficiently.

  FIG. 15 shows a configuration diagram of a refrigeration cycle in a case where a reheat dehumidification method in which the blowout temperature of the indoor unit is not lowered is adopted. The expansion device 105 is provided between the indoor heat exchangers 107 and 108, and the refrigerant is decompressed by the expansion device 105, so that the indoor heat exchanger 108 portion functions as a condenser and the indoor heat exchanger 107 portion functions as an evaporator. The outlet temperatures of the indoor heat exchanger 107 and the indoor heat exchanger 108 are mixed.

  In general air conditioning, a cross fin tube type heat exchanger is used for the outdoor heat exchanger 104 and the indoor heat exchangers 106, 107, and 108. However, with the aim of further reducing the cost of heat exchangers, it is required to use parallel flow type heat exchangers used in automobile radiators and air conditioners for cooling as condensers and evaporators. Then, it becomes a subject to distribute a refrigerant | coolant evenly from the header pipe | tube of a parallel flow type heat exchanger to several flat tubes.

  FIG. 1 is a diagram showing the structure of a conventional parallel flow heat exchanger. The parallel flow type heat exchanger has header pipes 21 and 22 where the refrigerant branches and merges at both ends of the flat tubes 11 arranged at equal intervals. The header pipes 21 and 22 are the refrigerant inflow and outflow pipes 31 and 32. Have Further, the inside of the flat tube 11 is divided by a thinner flow path. Fins 4 are installed between the flat tubes 11 to improve the efficiency of heat exchange. For example, when the refrigerant flows from the inflow pipe 31, the refrigerant is distributed to the flat tubes 11 in the header pipe 21. Then, after joining at the header pipe 22, it flows out from the outflow pipe 32. The same applies when the inflow pipe is 32 and the outflow pipe is 31.

  FIG. 2 is a diagram showing a parallel flow heat exchanger of the present embodiment. The basic configuration is the same as in FIG. The heat exchanger includes a flat tube 12, header tubes 21 and 22, an outflow tube 32 installed on the end surface of the header tube 22, an inflow tube 33 installed on the side surface of the header tube 21, and fins installed between the flat tubes 12. It is composed of four. In the present embodiment, a structure in which the swirling flow is induced in the header pipe 21 by the inflow pipe 33 will be described, but the swirling flow can also be induced in the header pipe 22 by the same structure. The positions of the header pipe 21 and the inflow pipe 33 and details of the flat pipe 12 will be described with reference to FIG.

  FIG. 3 is a view for explaining the positional relationship between the header pipe 21 and the inflow pipe 33 in FIG. As shown in FIG. 3, the header pipe 21 is installed so that the center axis 61 of the inlet pipe 33 and the longitudinal center axis 62 of the header pipe 21 are offset by a distance ε with respect to the pipe side surface of the header pipe 21. A swirling flow of the refrigerant is induced in the pipe 21. As will be described later, by inducing a swirling flow of the refrigerant in the header pipe 21, the liquid refrigerant is not biased in the vicinity of the inflow pipe in the header pipe 21 or below the header pipe 21. Liquid refrigerant can be distributed to the flat tube 12, so that the refrigerant can be evenly distributed to the flat tubes 12. Further, since the liquid refrigerant is distributed also in the header pipe 21 at the upper part (inflow pipe end part), it is not necessary to insert the inflow pipe end part deeply in the header pipe 21 to the lower part in the header pipe 21, so that the pressure loss of refrigerant flow Can also be reduced. Further, for example, as in the flat tube 12 shown in FIG. 3, an arc shape (concave shape) is formed so that the area of the insertion portion with respect to the header tube 21 is reduced, so that the turning force due to the resistance of the insertion portion of the flat tube 12 is reduced. Attenuation can be reduced. The flat tube 12 is not limited to the arc shape, and the same effect can be obtained by reducing the insertion length of the flat tube 12 into the header tube 21 as much as possible. For example, the insertion length into the header tube 21 is shortened to the processing limit at which the header tube 21 and the flat tube 12 can be joined while the end surface of the flat tube 12 is flat, and the end surface of the flat tube 12 is notched. Such as putting in.

  Next, in this embodiment, the gas-liquid refrigerant flow field of the conventional structure of FIG. 1 and the structure of this embodiment of FIG. 2 when the refrigerant is a gas-liquid two-phase flow will be described. FIG. 4 is a view showing a flow field in the header pipe 21 of FIG. 1 having a conventional structure. In FIG. 4, the heat exchanger includes a flat tube 11, a header tube 21, an inflow tube 31, and a gas-liquid refrigerant 5, and illustration of fins is omitted. In the conventional structure, the refrigerant flowing from the inflow pipe forms a laminar flow in which the upper part is a gas refrigerant and the lower part is a liquid refrigerant, and flows in the header pipe 21. In the vicinity of the inlet of the inflow pipe, the flow rate of the refrigerant is large, and the refrigerant is stirred by the collision of the flow with the flat tube 11 protruding into the header pipe 21. Therefore, the refrigerant easily flows into the flat tube 11 in the vicinity of the inflow tube 31, and the distribution amount increases. On the other hand, since the liquid refrigerant that has flowed as a laminar flow is bounced back by the wall end surface on the wall end surface downstream of the header pipe 21, the flow stagnates and the interface of the liquid refrigerant increases. For this reason, the refrigerant easily flows into the flat tube 11 near the wall end surface. Further, since the flat tube 11 located at the center of the header tube 21 has a lower interface than both ends of the header tube 21, the end surface (inlet) of the flat tube 11 is difficult to contact the liquid refrigerant. The inflow is relatively small. As described above, in the conventional structure, the distribution amount varies between the flat tubes 11.

  FIG. 5 is a diagram showing the flow field in the header pipe 21 of FIG. 2 which is the structure of this embodiment. In FIG. 5, the heat exchanger is composed of a flat tube 12, a header tube 21, an inflow tube 33, and a gas-liquid refrigerant 5, and illustration of fins is omitted. In the structure of the present embodiment, since the inflow pipe 33 is installed so that the swirling flow is induced inside the header pipe 21, the liquid refrigerant is pulled by the swirling flow of the gas refrigerant so as to cover the entire wall surface of the header pipe 21. Liquid refrigerant flows. The flat tube 12 not only shortens the insertion length into the header tube 21 but also has an end surface shape that follows the arc shape of the header tube 21. As a result, the flat tube has a uniform pressure distribution in the header tube 21 without disturbing the swirling flow. Further, the liquid refrigerant forming a liquid film on the wall surface of the header pipe 21 is likely to flow into the flat pipe 12. However, as the refrigerant flows downstream of the header pipe 21, the turning speed is attenuated. Accordingly, the swirl force can be adjusted by reducing the diameter of the inflow pipe 33 in accordance with the length of the header pipe 21 so that the swirl flow can be maintained in the entire header pipe 21. For example, a pipe having a small diameter is used for the inflow pipe 33, a taper or an orifice is provided at the pipe outlet, and the outflow portion is throttled.

  In addition, in the present embodiment, the case where it flows in from the inflow pipe provided in the header pipe installed on the lower side of the heat exchanger, flows out of the outflow pipe after joining in the header pipe installed on the upper side of the heat exchanger, has been described. However, the gravitational direction is not limited, and even when the header tube structure is upside down, or when the longitudinal direction of the header tube is the gravitational direction, the effect of reducing distribution variation can be obtained by turning the refrigerant.

Next, a second embodiment will be described with reference to the drawings. Since the configuration of the heat exchanger and the swivel induction structure are the same as those in the first embodiment, the description thereof is omitted. In this embodiment, the central axis of the inflow pipe is inclined in the longitudinal direction of the header pipe. Specifically, the inflow pipe insertion angle into the header pipe 21 is inclined by θ ₁ toward the downstream side of the header pipe 21.

FIG. 6 is a three-dimensional view of a parallel flow heat exchanger according to the second embodiment. In FIG. 6, the heat exchanger includes a flat tube 12, a header tube 21, and an inflow tube 34, and illustration of fins is omitted. When the inflow pipe 34 is installed in the header pipe 21, the inflow pipe 34 is inclined by θ ₁ toward the inflow pipe 34 with respect to the header pipe 21 so that the outlet of the inflow pipe 34 faces the downstream side of the header pipe 21. Configure. With this configuration, the longitudinal speed of the refrigerant flow in the header pipe 21 increases toward the downstream side of the header pipe 21, so that the swirl flow has a relatively long sustaining distance. The distribution variation to each flat tube 12 is improved.

Details of this structure are shown in FIG. The heat exchanger shown in FIG. 7 includes a flat tube 12, a header tube 21, an inflow tube 34, a refrigerant 5, a central axis 61 of the inflow tube 34, and a longitudinal central axis 62 of the header tube 21, and illustration of fins is omitted. . As shown in FIG. 7, the header pipe 21 is inclined by θ _{1 with} respect to the direction perpendicular to the side surface.

Moreover, it can also comprise so that the center axis | shaft of an inflow tube may incline in the longitudinal direction of a flat tube. FIG. 8 shows an example of a heat exchanger in which the inlet pipe insertion angle into the header pipe 21 is inclined by θ _{2 in} the flow direction of the flat pipe. The heat exchanger shown in FIG. 8 is composed of a flat tube 12, a header tube 21, an inflow tube 34, and a refrigerant 5. Thereby, the gas-liquid refrigerant flows more along the side wall surface of the header tube 21 and efficiently swirls. Can be induced.

As described above, by adjusting the installation angles θ ₁ and θ ₂ of the inflow pipe 34, the swirl flow can be more efficiently applied, and variations in refrigerant distribution can be reduced.

  Next, a third embodiment will be described with reference to the drawings. Since the configuration of the heat exchanger and the swivel induction structure are the same as those in the first embodiment, the description thereof is omitted.

  FIG. 9 shows an example of a heat exchanger when a plurality of inflow pipes 34 are inserted into the header pipe 21. The heat exchanger of FIG. 9 includes a flat tube 12, header tubes 21 and 22, four inflow tubes 34, an outflow tube 32, and fins 4. The inflow pipe 34 has a structure for inducing a swirling flow in the header pipe 21 as described in the above embodiments. In this embodiment, four inflow pipes 34 are installed for the header pipe 21. Thereby, compared with the case where a refrigerant | coolant flows into the header pipe | tube 21 from one inflow pipe, the dispersion | variation in the refrigerant | coolant distribution by attenuation | damping of rotation can be disperse | distributed to four places. As a result, it is possible to further reduce variation in refrigerant distribution among the flat tubes. In addition, by using a plurality of inflow locations to the header pipe 21, the turning force decreases as the refrigerant flow rate per inflow pipe decreases, but this can be dealt with by reducing the outlet pipe diameter of the inflow pipe 34. It is. For example, a pipe having a small diameter is used as the inflow pipe 34, or a taper or an orifice is provided at the pipe outlet. In FIG. 9, the inflow pipes 34 are installed at four places, but by using a larger number of inflow pipes 34, variation in refrigerant distribution can be further reduced. Further, the installation positions of the inflow pipes 34 are not limited to regular intervals with respect to the header pipe 21 and can be installed at unequal intervals to adjust the inflow flow rate to each flat pipe 12.

  Here, the header pipe 21 may be divided into a plurality of sections, and the inflow pipe 21 of the present embodiment may be connected to each of the plurality of sections. FIG. 10 shows an example of a heat exchanger in which the partition wall 7 is provided inside the header pipe 21 with respect to the heat exchanger of FIG. By dividing the header pipe by the partition wall 7 according to the number of the inflow pipes 34, small chambers are formed inside the header pipe 21, and the amount of refrigerant distributed to each flat pipe 12 in each small room is reduced from each inflow pipe 34. The amount of refrigerant flowing in is limited. Thereby, it is possible to reduce the variation in refrigerant distribution to each flat tube 12 more than the structure of FIG. In FIG. 10, the header pipe 21 is further divided into four small chambers by providing the partition walls 7 at equal intervals in the header pipe 21 for the four inflow pipes 34. As a result, all of the refrigerant flowing in from the inflow pipes 34 is distributed in each small room, so that a large distribution variation does not occur between the flat pipes 12 across the rooms. Further, the installation positions of the partition walls 7 are not limited to the header pipes 21 and may be installed at unequal intervals to adjust the flow rate of flow into each flat tube 12.

  Next, a fourth embodiment will be described with reference to the drawings. Since the configuration of the heat exchanger and the swivel induction structure are the same as those in the first and second embodiments, the description thereof is omitted. In this embodiment, a spiral swirl flow guide plate 8 is arranged inside the header pipe 21.

  FIG. 11 is a view showing a header pipe provided with a swirl flow guide plate 8 for maintaining swirl flow. In each of the above embodiments, the swirl flow guide plate 8 serving as a swirl flow guide is further inserted along the side wall surface in the header pipe 21. The heat exchanger of FIG. 11 includes a flat tube 12, a header tube 21, an inflow tube 34, and a swirl flow guide plate 8, and illustration of fins is omitted. FIG. 12 is a detailed structural view of the swirl flow guide plate 8 of FIG.

  In the present invention, a swirling flow is induced inside the header pipe 21 by adopting the same configuration as that of each of the above embodiments. However, as the longitudinal length of the header pipe 21 increases, the turning force is attenuated by the shearing force generated between the header pipe wall surface and the refrigerant or between the gas refrigerant and the liquid refrigerant as the refrigerant flows downstream in the header pipe 21. In addition, the effect of reducing variation in refrigerant distribution is reduced. Therefore, in the present embodiment, by disposing the spiral swirl flow guide plate 8 inside the header pipe 21, the refrigerant is guided to swivel on the inner wall of the header pipe 21. be able to. Further, by correcting the direction of the velocity vector with the swirling flow guide plate upstream of the header pipe 21, it is possible to suppress a phenomenon in which the refrigerant directly flows into the flat tube 12 by a strong swirling flow immediately after the refrigerant flows.

FIG. 12 shows the detailed structure of the swirl flow guide plate. In this embodiment, as shown in FIG. 12, the radial thickness of the swirl flow guide plate 8 is further increased from the upstream side to the downstream side of the header pipe 21. That is, the spiral-shaped swirl flow guide plate 8 is configured such that the width of the plate from the upstream side to the downstream side of the header pipe gradually increases as t ₁ <t ₂ <t ₃ . Thereby, the direction of the velocity vector of the refrigerant flow can be more forcibly corrected to the swirl direction even downstream of the header pipe 21 where the swirl force is attenuated, and the effect of the swirl flow can be maintained for a longer time. In addition, since the thickness of the swirling flow guide plate 8 is uniformly increased to apply a forcing force to the flow, the thickness of the plate is changed according to the flow, so that the pressure loss can be optimized. it can. As a result, variations in refrigerant distribution can be further suppressed. Furthermore, the combination with the installation of the plurality of inflow pipes 34 and the partition wall 7 shown in the third embodiment is also effective in reducing variations in refrigerant distribution.

  Next, a fifth embodiment will be described with reference to the drawings. Since the configuration of the heat exchanger and the swivel induction structure are the same as those in the first embodiment, the description thereof is omitted. FIG. 13 is a view showing a swirling induction structure by the inflow pipe 35 installed between the header pipes when the heat exchangers are arranged in two rows in the front and rear.

  In the heat exchanger of the present embodiment, the heat exchanger composed of the header tube, the flat tube, and the fins is arranged in two front and rear rows, and when the refrigerant flows from the front row header tube to the rear row header tube, The turning induction structure shown in each of the above embodiments is provided (that is, the heat exchanger on the downstream side of the refrigerant flow is configured by the parallel flow type heat exchanger of each of the above embodiments). The heat exchanger of FIG. 13 includes flat tubes 12 and 13, a front row header tube 22, a rear row header tube 23, an inflow tube (outflow tube) 35, a central axis 61 of the inflow tube 35, and a longitudinal central axis of the header tube 23. 62.

  In this embodiment, the parallel flow heat exchanger of each of the above embodiments, another parallel flow heat exchanger (a plurality of header tubes 22 and header tubes (not shown), header tubes 22 and header tubes ( A plurality of flat tubes 12 that connect to each other (not shown), an inflow tube (not shown) that is connected to a header tube (not shown) and into which refrigerant flows, and an outflow tube 35 that is connected to the header pipe 22 and through which refrigerant flows out. And a parallel flow type heat exchanger). Specifically, the outflow pipe 35 of another parallel flow type heat exchanger is connected to the inflow pipe 35 of the parallel flow type heat exchanger of each of the above embodiments, and the outflow pipe 35 of another parallel flow type heat exchanger. The refrigerant flowing out from the refrigerant flows into the header pipe 23 via the inflow pipe 35 of the parallel flow heat exchanger of each of the above embodiments.

  In this embodiment, since the heat exchangers are arranged in two rows, for example, when the header pipes are installed in the vertical direction with respect to the direction of gravity, when the refrigerant flows from the header pipe in the upper front row to the header pipe in the upper rear row, The liquid refrigerant stays in the header tube in the rear row, and the liquid refrigerant is difficult to be distributed to each flat tube. Therefore, in the present invention, as shown in FIG. 13, by applying the heat exchanger described in each of the above embodiments and inducing a swirling flow in the header tube 23 in the upper part of the rear row, the refrigerant is supplied to each flat tube 13. Distribute evenly. The refrigerant flow field and its effect of the present embodiment will be described. First, the refrigerant 5 flowing into the front row is distributed to each flat tube 12, then flows through the flat tube 12, and joins at the header tube 22. Next, the refrigerant 5 flows from the header pipe 22 through the inflow pipe (outflow pipe) 35 to the header pipe 23 installed in the rear-stage heat exchanger. At that time, in order to reduce the pressure loss due to the laminar flow of the refrigerant in the header pipe 23, a swirl flow is induced in the same manner as in the above embodiments. Since the gas-liquid refrigerant is swirling, the liquid refrigerant does not stay in the header pipe 23. For this reason, the pressure distribution in the header pipe 23 becomes more uniform, and the refrigerant distribution variation to the flat pipe 13 is improved. Since the end surface shape of the flat tube 13 is along the header tube (the end surface shape of the flat tube 13 is a concave shape), the retention of the refrigerant can be further suppressed.

11: Conventional flat tubes 12, 13: Flat tubes 21, 22, and 23 having changed end face shapes: Header tubes 31, 32: Inflow and outflow tubes 33, 34, and 35: Inflow and outflow tubes 4 having a swivel induction structure : Fin 5: Gas-liquid refrigerant 61: Center axis 62 of the inflow pipe: Center axis in the longitudinal direction of the header pipe 7: Partition wall provided in the header pipe 8: Spiral flow guide plate 101: Compressor 102: Four sides Valves 103 and 105: Throttling devices such as electric valves 104: Outdoor heat exchangers 106, 107 and 108: Indoor heat exchangers

Claims (9)

A first header pipe and a second header pipe;
A plurality of flat tubes connecting the first header tube and the second header tube;
An inflow pipe connected to the first header pipe and into which refrigerant flows;
An outflow pipe connected to the second header pipe and from which refrigerant flows out,
A parallel flow heat exchanger in which the inflow pipe is arranged so that a central axis of the inflow pipe is offset with respect to a central axis of the first header pipe.   The parallel flow heat exchanger according to claim 1, wherein a central axis of the inflow pipe is inclined in a longitudinal direction of the header pipe.   The parallel flow heat exchanger according to claim 2, wherein a central axis of the inflow pipe is inclined in a longitudinal direction of the flat pipe. In any one of Claims 1 thru | or 3,
The inflow pipe is composed of a plurality of inflow pipes,
The header tube is divided into a plurality of sections;
A parallel flow heat exchanger for connecting the inflow pipe to each of the plurality of compartments.   5. The parallel flow heat exchanger according to claim 1, wherein a spiral swirl flow guide plate is disposed inside the first header pipe.   6. The parallel flow heat exchanger according to claim 5, wherein the radial thickness of the swirl flow guide plate increases from the upstream side to the downstream side of the first header pipe.   7. The parallel flow heat exchanger according to claim 1, wherein an end surface of the first header pipe of the flat pipe connected to the first header pipe is formed in a concave shape. A parallel flow heat exchanger according to any one of claims 1 to 7,
A third header pipe and a fourth header pipe, a plurality of second flat pipes connecting the third header pipe and the fourth header pipe, and a second inflow pipe connected to the third header pipe and into which a refrigerant flows. A second parallel flow type heat exchanger having a second outflow pipe connected to the fourth header pipe and from which the refrigerant flows out,
The second outlet pipe is connected to the inlet pipe;
A parallel flow heat exchanger in which the refrigerant flowing out of the second outflow pipe flows into the first header pipe through the inflow pipe.   A compressor, a four-way valve, an indoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected to each other, and at least one of the indoor heat exchanger or the outdoor heat exchanger is defined in claim 1. A refrigeration cycle apparatus as any parallel flow type heat exchanger.

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