JP2020165569A - Heat exchanger - Google Patents

Abstract

To provide a heat exchanger capable of reducing a header width to reduce a refrigerant filling amount at low cost without increasing the number of components in a double-row heat exchanger.SOLUTION: A heat exchanger 5 comprises: a plurality of first flat pipes 11a laminated in a direction perpendicular to a refrigerant flow direction at a windward side; a plurality of second flat pipes 11b laminated in a direction perpendicular to the refrigerant flow direction at a leeward side; and a hollow header 12 in which one end parts of the plurality of first flat pipes 11a and the plurality of second flat pipes 11b are connected inward, wherein one end parts of the plurality of first flat pipes 11a and one end parts of the plurality of second flat pipes 11b are bent toward the header 12, and both are connected to the header 12 alternately in a direction perpendicular to the refrigerant flow direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to heat exchangers, particularly heat exchangers used in air conditioners.

Conventionally, there is known a heat exchanger having a structure in which both ends of a flat tube (heat transfer tube) are connected to a header and refrigerant is diverted into the flat tube in the header. A plurality of flat tubes are stacked in a direction perpendicular to the refrigerant flow direction. As shown in FIG. 7, as the heat exchanger 5A, there is an example in which two rows of flat tubes are arranged on the leeward side 11aA and the leeward side 11bA in order to improve the performance (see FIG. 7). When arranged in two columns in this way, headers 12aA and 12bA corresponding to the number of columns are required. Since the volume increases due to the plurality of headers 12aA and 12bA, the filling amount of the refrigerant also increases. Further, there is a problem that a connecting portion 121A for communicating a plurality of headers 12aA and 12bA is required, which increases the manufacturing cost.

On the other hand, for example, Patent Document 1 discloses a heat exchanger in which a plurality of heat transfer tubes (including the case of flat tubes) are connected to a main header via a connecting header that combines them in one place. In this heat exchanger, since the connection position of the heat transfer tube to the main header can be shifted, a large number of heat transfer tubes can be arranged, and heat exchange can be performed efficiently. Further, Patent Documents 2 to 4 disclose heat exchangers in which flat tubes in each row are connected side by side to one rectangular header. In this heat exchanger, by providing a partition plate inside the header, it can function as a folding portion for making a U-turn of the refrigerant between rows, and by extension, the header structure can be simplified and the manufacturability can be improved.

However, in the heat exchanger of Patent Document 1, since the number of members (particularly the connecting header) is increased, the man-hours and the manufacturing cost are increased in terms of manufacturing and cost, and there is still a problem that the filling amount of the refrigerant cannot be reduced. Further, in the heat exchangers of Patent Documents 2 to 4, since the flat tubes of each row are connected side by side, there is a problem that the required header width becomes large and the volume increases, so that the compactness cannot be achieved and the refrigerant is filled. There was still the problem of not being able to reduce the amount.

Japanese Unexamined Patent Publication No. 2011-80704 Japanese Unexamined Patent Publication No. 2013-2731 Japanese Unexamined Patent Publication No. 2013-134016 JP 2015-113983

The present invention has been made in view of the above problems, and in a heat exchanger in which a plurality of heat transfer tubes are arranged in two rows on the windward side and the leeward side, heat exchange capable of reducing the amount of refrigerant charged at low cost is possible. The purpose is to provide a vessel.

The present invention is grasped by the following configuration in order to achieve the above object.
(1) The first aspect of the present invention is a heat exchanger, in which a plurality of first flat pipes laminated in a direction perpendicular to the refrigerant flow direction on the wind side and a plurality of first flat pipes stacked in a direction perpendicular to the refrigerant flow direction on the leeward side and perpendicular to the refrigerant flow direction on the leeward side. A plurality of second flat tubes laminated in the direction of the above, and a hollow header to which one end of the plurality of first flat tubes and the plurality of second flat tubes are connected. One end of the first flat pipe and one end of the plurality of second flat pipes are bent toward the header, and both are alternately connected to the header in a direction perpendicular to the refrigerant flow direction. It is characterized by being done.

(2) In the heat exchanger of (1) above, one end of the plurality of first flat tubes and the plurality of second flat tubes are viewed from above when viewed from a direction perpendicular to the refrigerant flow direction. They are arranged line-symmetrically in the longitudinal direction parallel to the refrigerant flow direction (the direction parallel to the direction from one end to the other end of the first flat pipe).

(3) In the heat exchanger of (1) or (2), one end of the plurality of first flat tubes and the plurality of second flat tubes includes a bent portion that bends toward the header and a bent portion. It has a connecting portion that bends from the bent portion in a direction parallel to the main body portion and is connected to the header.

According to the present invention, in a heat exchanger in which a plurality of heat transfer tubes are arranged in two rows on the leeward side and the leeward side, it is possible to provide a heat exchanger capable of reducing the amount of refrigerant charged at low cost.

It is a figure explaining the structure of the air conditioner to which the heat exchanger according to the embodiment of this invention is applied. It is a figure explaining the heat exchanger which concerns on embodiment of this invention, (a) is a plan view of a heat exchanger, (b) is a front view of a heat exchanger. It is a perspective view explaining the flat tube and the header of the heat exchanger which concerns on embodiment of this invention. FIG. 3 is a diagram illustrating a flat tube and a header in a top view. It is a figure explaining the flat tube and the header of the heat exchanger which concerns on the modification 1 of this invention from the top view. It is a figure explaining the flat tube and the header of the heat exchanger which concerns on the modification 2 of this invention from the top view. It is a figure explaining the case where the header is provided for each of two rows of flat tubes in the conventional heat exchanger from the top view.

(Embodiment)
Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “embodiments”) will be described in detail with reference to the accompanying drawings. The same elements are numbered the same throughout the description of the embodiment.

(Overall configuration of air conditioner)
FIG. 1 shows the configuration of an air conditioner 1 to which the heat exchanger 5 according to the embodiment of the present invention is applied. As shown in FIG. 1, the air conditioner 1 includes an indoor unit 2 and an outdoor unit 3. The indoor unit 2 is provided with an indoor heat exchanger 4, and the outdoor unit 3 is provided with a compressor 6, an expansion valve 7, a four-way valve 8 and the like in addition to the outdoor heat exchanger 5. There is.

During the heating operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor 6 of the outdoor unit 3 flows into the indoor heat exchanger 4 via the four-way valve 8. In the figure, the refrigerant flows in the direction of the black arrow. During the heating operation, the indoor heat exchanger 4 functions as a condenser, and the refrigerant that has exchanged heat with air condenses and liquefies. After that, the high-pressure liquid refrigerant is depressurized by passing through the expansion valve 7 of the outdoor unit 3, becomes a low-temperature low-pressure gas-liquid two-phase refrigerant, and flows into the outdoor heat exchanger 5. The outdoor heat exchanger 5 functions as an evaporator, and the refrigerant that has exchanged heat with the outside air is gasified. After that, the low-pressure gas refrigerant is sucked into the compressor 6 via the four-way valve 8.

During the cooling operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor 6 of the outdoor unit 3 flows into the outdoor heat exchanger 5 via the four-way valve 8. In the figure, the refrigerant flows in the direction of the white arrow. During the cooling operation, the outdoor heat exchanger 5 functions as a condenser, and the refrigerant that has exchanged heat with the outside air condenses and liquefies. After that, the high-pressure liquid refrigerant is depressurized by passing through the expansion valve 7 of the outdoor unit 3, becomes a low-temperature low-pressure gas-liquid two-phase refrigerant, and flows into the indoor heat exchanger 4. The indoor heat exchanger 4 functions as an evaporator, and the refrigerant that has exchanged heat with air is gasified. After that, the low-pressure gas refrigerant is sucked into the compressor 6 via the four-way valve 8.

(Heat exchanger)
The heat exchanger of this embodiment can be applied to the indoor heat exchanger 4 and the outdoor heat exchanger 5, but in the following description, the heat of the outdoor unit 3 which functions as an evaporator during the heating operation. It will be described as being applied to the exchanger 5. The heat exchanger 5 of the outdoor unit 3 may be used as a flat type or as a plan view L type. Usually, when it is used in a plan view L shape, it is obtained by bending a heat exchanger 5 formed in a flat shape. Specifically, an assembly process of assembling a flat heat exchanger 5 with a member coated with a brazing material on the surface, and a brazing process of putting the assembled flat heat exchanger 5 into a furnace and brazing. The L-shaped heat exchanger 5 is manufactured through a bending step of bending the brazed flat heat exchanger 5 into an L-shape. Hereinafter, the heat exchanger of the present invention will be described as a flat heat exchanger 5.

2A and 2B are views for explaining the heat exchanger 5 according to the present embodiment, FIG. 2A shows a plan view of the heat exchanger 5, and FIG. 2B shows a front view of the heat exchanger 5. There is. The flat pipe 11 (first flat pipe 11a and second flat pipe 11b) has a flat cross section extending in the direction in which air flows, and a plurality of flow paths through which the refrigerant flows are provided in the air flow direction. It is formed side by side. The heat exchanger 5 includes a plurality of first flat tubes 11a arranged in the vertical direction so that the wide surfaces (wide surfaces) of the side surfaces of the flat tubes 11 face each other, and a plurality of first flat tubes 11a also arranged in the vertical direction. The second flat tube 11b, the pair of left and right headers 12 connected to both ends of the first flat tube 11a and the second flat tube 11b, and the first flat tube 11a and the second flat tube 11b are arranged so as to intersect each other. It is configured to include a plurality of fins 111 joined to the flat tube 11. In addition to these, the heat exchanger 5 is provided with a refrigerant pipe in the header 12 that connects the heat exchanger 5 to other elements of the air conditioner 1 and allows the refrigerant to flow.

The flat tubes 11 are arranged in parallel in the vertical direction with an interval S1 for air to pass through, and both ends thereof are connected to a pair of headers 12. Specifically, a plurality of first flat tubes 11a and second flat tubes 11b along the left-right direction are arranged in the vertical direction at a predetermined interval S1, and both ends thereof are connected to the header 12.

The header 12 has a cylindrical shape, and the refrigerant supplied to the heat exchanger 5 may be branched into a plurality of flat pipes 11 or the refrigerants flowing out from the plurality of flat pipes 11 may be merged therein. A refrigerant flow path (not shown) is formed. Although the cylindrical header 12 is shown here, the cross section may have a shape other than a circular shape, as will be described later.

The fins 111 have a flat plate shape that is arranged so as to extend in a direction intersecting the flat tube 11 in a front view, and are arranged at a predetermined arrangement pitch in the left-right direction with an interval for passing air.

(Flat tube and header)
Next, the connection relationship between the first flat tube 11a, the second flat tube 11b, and the header 12 of the heat exchanger 5 according to the present embodiment will be described with reference to FIGS. 3 to 6. The header 12 is provided at one end and the other end of the flat tube 11, but the header 12 on the one end side will be described below. Further, in the present embodiment, the first flat tube 11a side (upper side in the figure) is referred to as the leeward side, and the second flat tube 11b side (lower side in the figure) is referred to as the leeward side. Note that fins 111 are omitted in FIGS. 3 to 6.

As shown in FIGS. 3 and 4, the inside of the header 12 is formed to be hollow so that the refrigerant is divided into a plurality of flat tubes 11. The flat pipes 11 are a plurality of first flat pipes 11a laminated in a direction perpendicular to the refrigerant flow direction on the windward side, and a plurality of second flat pipes 11a laminated in a direction perpendicular to the refrigerant flow direction on the leeward side. They are arranged in two rows with 11b. One end of the plurality of first flat tubes 11a and the plurality of second flat tubes 11b is connected to one header 12. One end of each is connected so as to be parallel to the radial direction of the header 12.

In this way, since the two rows of flat tubes 11 are connected to one header 12, the diameter of the header 12 is not increased, the internal volume is reduced by sharing the header 12, and the space between the headers 12 is reduced. The connection part of is also unnecessary.

Here, one end of the plurality of first flat tubes 11a and one end of the plurality of second flat tubes 11b are bent toward the header 12 as shown in FIG. That is, one end of the first flat tube 11a on the leeward side is bent to the leeward side, and one end of the second flat tube 11b on the leeward side is bent to the leeward side. Then, both one end of the first flat tube 11a and one end of the second flat tube 11b alternate in the direction perpendicular to the refrigerant flow direction (vertical direction in the drawing). Connected to 12.

The specific mode of bending is as follows. The first flat tube 11a has a main body portion 11a1 extending from a header 12 on the other end side (left side in the drawing) (not shown) and a main body portion 11a1 toward the header 12 in front of the header 12 shown. It has a bent portion 11a2 that bends, and a connecting portion 11a3 that is bent and extended again from the bent portion 11a2 in a direction parallel to the main body portion 11a1 and connected to the header 12. The tip of the connecting portion 11a3 opens inside the header 12 to form the refrigerant outflow inlet 11a4.

Similarly, one end of the second flat tube 11b is a main body 11b1 extending from a header 12 on the other end side (left side in the drawing) (not shown), and a header 12 in front of the header 12 shown. It has a bent portion 11b2 that bends from the main body portion 11b1 toward the main body, and a connecting portion 11b3 that is bent and extended again from the bent portion 11b2 in a direction parallel to the main body portion 11b1 and connected to the header 12. The same applies to the point that the tip of the connecting portion 11b3 opens inside the header 12 to form the refrigerant outflow inlet 11b4.

FIG. 4 is a top view of the heat exchanger according to the present embodiment. As shown in FIG. 4, one end of the first flat tube 11a and one end of the second flat tube 11b are arranged in a staggered manner on the leeward side and the leeward side in a top view, and the header 12 About the symmetry line Q extending in the longitudinal direction (the direction parallel to the direction from one end to the other end of the first flat pipe) intersecting the axis P of the above and parallel to the flow direction of the refrigerant of the heat exchanger 5. They are arranged line-symmetrically. The position of the symmetry line Q is not limited to this embodiment, and does not necessarily have to intersect the axis P of the header 12.

In this way, one end of the first flat tube 11a and one end of the second flat tube 11b are alternately laminated so as to be staggered on the leeward side and the leeward side in the top view. By arranging them in a heat exchange arrangement so as to be stacked in a direction perpendicular to the refrigerant flow direction (vertical direction, axial direction of the header 12), it is possible to connect to the same header 12 only by bending in the horizontal direction. Becomes easier.

Further, since one end of the first flat tube 11a and one end of the second flat tube 11b are line-symmetrical in the longitudinal direction, the same flat tube 11 can be used by inverting (turning over). It is possible to manufacture the heat exchanger 5 at low cost without the need to manufacture the flat tubes 11 having different shapes.

(Modification example 1)
One end of the first flat tube 11a and the second flat tube 11b can also be deformed like the heat exchanger 50 shown in FIG. That is, one end of the first flat tube 11a is formed only by the bent portion 11a2 which is bent and extended from the main body portion 11a1 toward the header 12 and connected to the header 12. Similarly, one end of the second flat tube 11b is formed only by the bent portion 11b2 which is bent and extended from the main body portion 11b1 toward the header 12 and connected to the header 12. In other words, the respective connecting portions 11a3 and connecting portion 11b3 provided in the above-described embodiment are omitted, and the bent portion 11a2 and the bent portion 11b2 are directly connected to the header 12.

(Modification 2)
Up to this point, the header 12 has been described as having a cylindrical cross section, but the cross-sectional shape is not limited to a cylinder. For example, it may have a triangular shape as shown in FIG. In this case, as shown in the first modification, when the bent portions 11a2 and the bent portions 11b2 are directly connected to the header 12, manufacturing becomes easy.

(Effect of embodiment)
Since the heat exchanger is as described above, in the present embodiment, the amount of refrigerant charged in the heat exchangers arranged in two rows (two rows of the first flat pipe 11a and the second flat pipe 11b) can be reduced at low cost. A heat exchanger 5 that can be reduced can be provided. That is, by bending one end of the flat tube 11, it is possible to displace the position of one end without increasing the number of parts. Further, by connecting the headers 12 so as to be stacked in the axial direction, the headers 12 can be miniaturized, the space around the headers 12 can be saved, and the material cost can be reduced.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and modifications are made within the scope of the gist of the present invention described in the claims. It can be changed.

1 ... Air conditioner 2 ... Indoor unit 3 ... Outdoor unit 4 ... Heat exchanger (indoor)
5,50,51 ... Heat exchanger (outdoor)
6 ... Compressor 11 ... Flat tube,
11a ... 1st flat tube, 11a1 ... main body, 11a2 ... bent, 11a3 ... connecting, 11a4 ... refrigerant outflow port 11b ... second flat tube, 11b1 ... main body, 11b2 ... bent, 11b3 ... connecting, 11b4 ... Refrigerant outflow port 111 ... Fin 12 ... Header

Claims (3)

A plurality of first flat pipes stacked in a direction perpendicular to the refrigerant flow direction on the windward side,
A plurality of second flat pipes stacked in a direction perpendicular to the refrigerant flow direction on the leeward side,
It comprises a plurality of first flat tubes and a hollow header in which one end of the plurality of second flat tubes is connected inward.
One end of the plurality of first flat pipes and one end of the plurality of second flat pipes are bent toward the header, and both are alternately arranged in a direction perpendicular to the refrigerant flow direction. A heat exchanger characterized by being connected to a header. One end of the plurality of first flat pipes and the plurality of second flat pipes are line-symmetrical with respect to the longitudinal direction parallel to the refrigerant flow direction in a top view viewed from a direction perpendicular to the refrigerant flow direction. The heat exchanger according to claim 1, wherein the heat exchanger is arranged. One end of the plurality of first flat tubes and the plurality of second flat tubes is bent toward the header and bent in a direction parallel to the main body from the bent portion. The heat exchanger according to claim 1 or 2, wherein the heat exchanger has a connecting portion connected to the above.

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