JP6816411B2 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger used in an air conditioner or the like.

As shown in FIG. 6, the heat exchanger 100 used in an air conditioner or the like usually has a plurality of flat tubes 101 arranged in the vertical direction so that the side surfaces (wide surfaces) face each other, and both ends of the flat tubes 101. A pair of left and right headers 102 to which the portions are connected and a plurality of fins 103 joined in a direction intersecting the plurality of flat tubes 101 are provided, and a space formed between the flat tubes 101 and the fins 103 is provided. Heat exchange is performed between the passing air and the refrigerant flowing in the flat space 101.

In this type of heat exchanger 100, it is difficult to align the lower end portion of the header 102 with the lower end portion of the fin 103 due to the relationship between the connectable range H of the flat tube 101 in the header 102 and the arrangement pitch of the flat tube 101. The step D between the lower end of the header 102 and the lower end of the fin 103 creates an opening region S2 (inside the broken line frame) continuous in the left-right direction at the lower end of the heat exchanger 100. This opening region S2 has the same opening area as the opening region S2 and has a ventilation resistance as compared with the heat exchange region S1 (inside the broken line frame) in which a plurality of flat tubes 101 and a plurality of fins 103 exist between the left and right headers 102. Is small, air easily flows into the opening region S2, which does not contribute to heat exchange between the air and the refrigerant, and the amount of ventilation in the heat exchange region S1 is relatively reduced, resulting in a decrease in heat exchange performance.

Therefore, it has been proposed to fill the opening region S2 generated at the lower end of the heat exchanger with another member. For example, in the heat exchanger described in Patent Document 1, a spacer is arranged in the opening region S2 at the lower end.

Japanese Unexamined Patent Publication No. 2013-139918

However, if the gap generated at the lower end of the heat exchanger is filled with a separate member, not only the number of parts (type) and assembly man-hours will increase, but also the drainage property of the condensed water generated in the heat exchanger will decrease due to the separate member. There was a risk of doing so.

Therefore, the present invention has been made in view of the above problems, and the air flowing in the opening region S2 at the lower end portion is avoided while avoiding an increase in the number of parts and assembly man-hours and a decrease in drainage property of condensed water. The purpose is to provide a heat exchanger that can reduce the amount of ventilation and improve the heat exchange performance.

The present invention has been proposed in order to achieve the above object, and the invention according to claim 1 comprises a plurality of flat tubes arranged in the vertical direction so that the side surfaces face each other, and the plurality of flat tubes. A pair of headers to which the left and right ends are connected and a plurality of fins joined in a direction intersecting the plurality of flat tubes are provided, and the headers are formed in a cylindrical portion and upper and lower ends of the cylindrical portion. The plurality of fins have a plurality of fitting portions into which the plurality of flat tubes are inserted, and the plurality of fitting portions below the bottom fitting portion of the plurality of fitting portions. It has at least one sub-fitting portion provided in the arrangement direction of the fitting portions at the same arrangement pitch as the plurality of fitting portions, and at least a part of the sub-fitting portion has the closed portion flattened. It is characterized in that it is located on a projection plane projected in the extending direction of the tube, or is located below the projection plane.

The invention according to claim 2 is characterized in that a dummy tube whose end is not connected to the header is inserted in at least a part of the sub-fitting portion of the plurality of fins.

According to the present invention, it is possible to provide a heat exchanger capable of improving heat exchange performance while avoiding an increase in the number of parts and assembly man-hours and a decrease in drainage property of condensed water.

It is explanatory drawing which shows the structure of the air conditioner to which the heat exchanger which concerns on embodiment of this invention is applied. It is a figure which shows the heat exchanger which concerns on 1st Embodiment of this invention, (a) is the plan view of the heat exchanger which concerns on 1st Embodiment, (b) is the front surface of the heat exchanger which concerns on 1st Embodiment. It is a figure. It is a figure which shows the lower part of the heat exchanger which concerns on 1st Embodiment of this invention, (a) is the front view of the main part which shows the lower part of the heat exchanger which concerns on 1st Embodiment, (b) is 1st Embodiment. It is a main part perspective view which shows the lower part of the heat exchanger which concerns on. It is a figure which shows the lower part of the heat exchanger which concerns on another embodiment of this invention, (a) is the front view of the main part which shows the lower part of the heat exchanger which concerns on 2nd Embodiment, (b) is the 3rd Embodiment. It is a front view of the main part which shows the lower part of the heat exchanger which concerns on. It is a figure which shows the heat exchanger which concerns on 1st Embodiment of this invention, (a) is the cross-sectional view of AA' of the heat exchanger which concerns on 1st Embodiment, (b) is the heat which concerns on 1st Embodiment. It is a cross-sectional view of BB'of the exchanger. It is a figure which shows the heat exchanger which concerns on the prior art, (a) is the front view of the heat exchanger which concerns on the prior art, (b) is the front view of the main part which shows the lower part of the heat exchanger which concerns on the prior art.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the drawings. The same elements will be described with the same reference numerals throughout the description of the embodiments.

[Air conditioner]
FIG. 1 is an explanatory diagram showing a configuration of an air conditioner to which the heat exchanger 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 for the indoor unit, 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 of the indoor unit 2 via the four-way valve 8. The refrigerant that has exchanged heat with air in the indoor heat exchanger 4 (condenser) 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 refrigerant that has exchanged heat with the outside air in the outdoor heat exchanger 5 (evaporator) evaporates and gasifies. 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. The refrigerant that has exchanged heat with the outside air in the outdoor heat exchanger 5 (condenser) 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 of the indoor unit 2. The refrigerant that has exchanged heat with air in the indoor heat exchanger 4 (evaporator) evaporates and gasifies. 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 the present invention can be applied to both the indoor heat exchanger 4 of the indoor unit 2 and the outdoor heat exchanger 5 of the outdoor unit 3. In the following description, the outdoor heat exchanger 5 of the outdoor unit 3 It will be described as being applied to. The outdoor heat exchanger 5 of the outdoor unit 3 is usually L-shaped in a plan view, and can be obtained by bending a flat heat exchanger. Specifically, an assembly process of assembling a flat outdoor heat exchanger 5 with a member coated with a brazing material on the surface and brazing of putting the assembled flat outdoor heat exchanger 5 into a furnace and brazing. The L-shaped outdoor heat exchanger 5 is manufactured through a process and a bending step of bending the brazed flat outdoor heat exchanger 5 into an L-shape. Hereinafter, the heat exchanger of the present invention will be described as a flat outdoor heat exchanger 5 before bending.

2A and 2B are views showing a heat exchanger according to the first embodiment of the present invention, FIG. 2A is a plan view of the heat exchanger according to the first embodiment, and FIG. 2B is a heat exchanger according to the first embodiment. A front view of the exchanger, FIG. 3 is a view showing a lower portion of the heat exchanger according to the first embodiment of the present invention, and FIG. 3A is a front view of a main part showing the lower portion of the heat exchanger according to the first embodiment. FIG. 3B is a perspective view of a main part showing the lower part of the heat exchanger according to the first embodiment. As shown in FIGS. 2 and 3, the outdoor heat exchanger 5 has a plurality of flat tubes 11 arranged in the vertical direction so that the side surfaces 11b (wide surfaces) face each other, and the left and right ends of the flat tubes 11. It includes a pair of headers 12 to be connected, and a plurality of fins 13 joined in a direction intersecting the flat tube 11.

The flat tube 11 has a flat shape extending in the air flow direction, and a plurality of refrigerant flow paths 11a arranged in the air flow direction are formed therein. The flat tubes 11 are arranged side by side in the vertical direction with a predetermined interval (arrangement pitch P) for air to pass through, and their left and right ends are connected to a pair of headers 12.

The header 12 has a cylindrical portion 12c having a cylindrical shape, and inside the header 12, the refrigerant supplied to the outdoor heat exchanger 5 may be branched into a plurality of flat pipes 11 and flow into the plurality of flat pipes 11. A refrigerant flow path (not shown) for merging the refrigerant flowing out of the water is formed. In the header 12, a cap 12a is fitted into the upper and lower ends of the cylindrical portion 12c and brazed to form a closing portion 12d (inside the broken line frame). In order to reduce the amount of refrigerant accumulated in the header 12, it is preferable that the position of the bottom surface 12b inside the header 12 is as high as possible. Therefore, the cap 12a usually has a convex shape toward the inside of the header 12. Since there is no refrigerant flow path inside the height range of the cap 12a from the lower end of the header 12 (the non-connectable range H to the flat tube 11), it is difficult to connect the flat tube 11 in the non-connectable range H. is there.

The fins 13 have a flat plate shape extending in a direction intersecting the flat tube 11 in a front view, and are arranged in parallel with a predetermined interval for air to pass through. Here, the region where the plurality of flat tubes 11 and the plurality of fins 13 exist between the left and right headers 12 is designated as the heat exchange region S1.

A plurality of fitting portions 13a to be fitted with the flat tube 11 are formed in the fin 13, and the flat tube 11 is inserted into these fitting portions 13a to be fitted with the flat tube 11. By brazing in this state, the fin 13 and the flat tube 11 are integrally joined. The fitting portion 13a of the present embodiment has a notched groove shape with an opening on the windward side, but may have a punched hole shape.

The fitting portion 13a is formed on the fin 13 with the arrangement pitch P of the flat tube 11. If the fin 13 is longer on the lower side than the lowermost fitting portion 13a'(fixed portion), the fin 13 is easily broken. Therefore, the length from the fitting portion 13a'to the lower end of the fin 13 is the minimum length. Therefore, as shown in FIG. 6, in the conventional heat exchanger 100, the lower end of the header 102 and the fins are related to the unconnectable range H of the flat tube 101 in the header 102 and the arrangement pitch P of the flat tube 101. It is difficult to align the lower end of the 103, and the opening region S2 (broken frame) continuous in the left-right direction with the lower end of the heat exchanger 100 due to the step D between the lower end of the header 102 and the lower end of the fin 103. Inside) occurs. This opening region S2 has the same opening area as the opening region S2 and has a ventilation resistance as compared with the heat exchange region S1 (inside the broken line frame) in which a plurality of flat tubes 101 and a plurality of fins 103 exist between the left and right headers 102. Is small, air easily flows into the opening region S2, which does not contribute to heat exchange between the air and the refrigerant, and the amount of ventilation in the heat exchange region S1 is relatively reduced, resulting in a decrease in heat exchange performance. When the opening region S2 is filled with a separate member, not only the number of parts (type) and the assembly man-hours increase, but also the separate member may hinder the drainage of the condensed water generated in the heat exchanger.

Therefore, in the outdoor heat exchanger 5 according to the embodiment of the present invention, the amount of ventilation in the opening region S2 is reduced and the heat exchange performance is improved without using a separate member. Specifically, the plurality of fins 13 are provided below the lowermost fitting portion 13a'in the arrangement direction of the plurality of fitting portions 13a at the same arrangement pitch as the plurality of fitting portions 13a, and the flat tube 11 is provided. It has at least one sub-fitting portion 13c that is not plugged in. Further, at least a part of the sub-fitting portion 13c is located on the projection surface in the extending direction of the flat tube 11 of the cap 12a, or is located below the projection surface. 5 (a) is a cross-sectional view taken along the line AA'in FIG. 2 (a), and FIG. 5 (b) is a cross-sectional view taken along the line BB'in FIG. 2 (a). X in FIG. 5B shows a projection plane in the extending direction of the flat tube 11 of the cap 12a. In the heat exchanger 5 shown in FIG. 5 (b), the cap 12a is located in the projection surface X. By doing so, the fins 13 can be arranged at the position of the opening region S2 to increase the ventilation resistance without using a separate member as in the prior art, and the heat exchange performance of the outdoor heat exchanger 5 is deteriorated. Can be prevented. Further, it is possible to avoid an increase in the number of parts and assembly man-hours and a decrease in drainage property of condensed water due to the provision of a separate member.

Further, a dummy tube 14 whose end is not connected to the header 12 can be arbitrarily provided in the sub-fitting portion 13c, and it is desirable to provide the extension portion 13b when it is necessary to secure the strength. For example, in the outdoor heat exchanger 5 of the present embodiment, as shown in FIG. 3B, a pipe material made of the same material as the flat pipe 11 and shorter than the flat pipe 11 is used as a dummy pipe 14, and this is used as an extension portion. It is fitted to the sub-fitting portion 13c of 13b.

Here, looking at the arrangement of the extension portion 13b with respect to the sub fitting portion 13c, the sub fitting portion 13c is the lowest fitting portion 13a among the plurality of fitting portions 13a into which the flat tube 11 is inserted. It will be provided below the'with the same arrangement pitch P as the plurality of fitting portions 13a. With this configuration, the extension portion 13b also has the same shape as the other parts of the fin 13, so that the desired fin 13 can be easily manufactured, the number of parts and assembly man-hours are increased, and the drainage property of condensed water is increased. It is possible to provide an outdoor heat exchanger 5 capable of reducing the amount of air flowing through the opening region S2 at the lower end and improving the heat exchange performance while avoiding the decrease in heat exchange performance.

Further, when the dummy pipe 14 is provided in the sub-fitting portion 13c, not only the strength of the extension portion 13b can be secured, but also the ventilation resistance of the region (not shown) in which the dummy pipe 14 and the plurality of fins 13 exist between the headers 12. Is approximated to the ventilation resistance of the heat exchange region S1 (inside the broken line frame), and it is possible to suppress the bias of the ventilation amount and further improve the heat exchange performance.

In the outdoor heat exchanger 5 of the embodiment of the present invention described above, a plurality of flat tubes 11 arranged in the vertical direction so that the side surfaces 11b face each other are connected to the left and right ends of the plurality of flat tubes 11. The header 12 includes a pair of headers 12 and a plurality of fins 13 joined in a direction intersecting the plurality of flat tubes 11, and the header 12 has a cylindrical portion 12c and a closing portion formed at the upper and lower ends of the cylindrical portion 12c. The plurality of fins 13 have 12d, and the plurality of fins 13 have a plurality of fitting portions 13a into which the plurality of flat tubes 11 are inserted, and a plurality of fitting portions 13a below the bottom fitting portion 13a'of the plurality of fitting portions 13a. A plurality of fitting portions 13a and at least one sub-fitting portion 13c provided at the same arrangement pitch P are provided in the arrangement direction of the fitting portion 13a, and at least a part of the sub-fitting portion 13c has a closing portion 12d. Since it is located on the projection surface X projected in the extending direction of the flat pipe 11 or below the projection surface X, it is possible to avoid an increase in the number of parts and assembly steps and a decrease in drainage of condensed water. At the same time, the amount of air flowing through the opening region S2 at the lower end can be reduced, the amount of ventilation can be suppressed, and the heat exchange performance can be improved.

Further, since a dummy tube 14 whose end is not connected to the header 12 is provided in at least a part of the sub-fitting portions 13c of the plurality of fins 13, not only the strength of the extension portion 13b can be ensured, but also between the headers 12 It is possible to approximate the ventilation resistance of the region where the dummy pipe 14 and the plurality of fins 13 exist (not shown) to the ventilation resistance of the heat exchange region S1 and suppress the bias of the ventilation amount to further improve the heat exchange performance. become.

[Other Embodiments]
Next, the outdoor heat exchangers 5B to 5G according to the second to third embodiments of the present invention will be described with reference to FIGS. 4 and 5. However, for the configuration common to the embodiment, the description of the embodiment is incorporated by using the same reference numerals as those of the embodiment.

As shown in FIG. 4A, the outdoor heat exchanger 5B of the second embodiment includes a fixing member 15 that covers the lower end portion of the header 12, and the extension portion 13b of the fin 13 is the lower end portion of the header 12. It extends beyond the portion to the same height as the lower end portion of the fixing member 15. By doing so, even in the outdoor heat exchanger 5B provided with the fixing member 15 of the header 12, the step between the lower end portion of the fixing member 15 and the lower end portion of the fin 13 is eliminated, and the lower end of the outdoor heat exchanger 5B is eliminated. The amount of ventilation in the opening region S2 generated in the portion can be reduced.

The outdoor heat exchanger 5 is fixed to the base (not shown) of the outdoor unit 3 by a fixing means (not shown) provided at the lower end of the header 12, but the portion facing the extension portion 13b of the base is the lower end of the header. If it is lower than, it is necessary to make the extending length of the extension portion 13b longer than the lower end of the header. In this case, as shown in FIG. 4B, the outdoor heat exchanger 5C of the third embodiment extends the extension portion 13b of the fin 13 at the same height as or below the lower end portion of the header 12. A plurality of sub-fitting portions 13c arranged in the vertical direction are provided in the extension portion 13b, and a dummy tube 14 is inserted into each of the extension portions 13b. As a result, not only the strength of the extension portion 13b can be ensured by the plurality of dummy tubes 14, but also the ventilation resistance equivalent to that of the heat exchange region S1 can be adjusted.

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. For example, in the heat exchanger described above, a dummy tube made of the same material as the flat tube is used, but the shape is such that it can be inserted into the sub-fitting portion of the fin, and the fin is fixed to the sub-fitting portion. It is included in the present invention if it has enough rigidity to ensure the strength of the above.

1 Air conditioner 2 Indoor unit 3 Outdoor unit 4 Heat exchanger (indoor)
5,5B, 5C heat exchanger (outdoor)
6 Compressor 11 Flat pipe 11a Refrigerant flow path 12 Header 13 Fin 13a Fitting part 13a'Lowest fitting part 13b Extension part 13c Sub fitting part 14 Dummy pipe 14E, 14F, 14G Dummy pipe 15 Cap

Claims (2)

Multiple flat tubes arranged vertically so that the sides face each other,
A pair of headers in which the left and right ends of the plurality of flat tubes are connected,
A plurality of flat plate-shaped fins joined in a direction intersecting the plurality of flat tubes.
The header has a cylindrical portion and a closed portion formed at the upper and lower ends of the cylindrical portion.
The plurality of fins
A plurality of fitting portions into which the plurality of flat tubes are inserted, and
At least one sub-fitting portion provided below the bottom fitting portion among the plurality of fitting portions at the same arrangement pitch as the plurality of fitting portions in the arrangement direction of the plurality of fitting portions. Have and
At least a part of the sub-fitting portion is located on a projection surface in which the closing portion is projected in the extending direction of the flat tube, or is located below the projection surface.
Heat exchanger characterized in that. The heat exchanger according to claim 1, wherein a dummy tube whose end is not connected to the header is inserted in at least a part of the sub-fitting portion of the plurality of fins.

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