JPWO2017104049A1 - HEAT EXCHANGER, AIR CONDITIONER EQUIPPED WITH THE SAME, AND METHOD FOR PRODUCING HEAT EXCHANGER - Google Patents

Abstract

In the heat exchanger (5), the joint portion (25) connecting the first flat tube (23a) in the first row (5a) and the second flat tube (23b) in the second row (5b) has a first opening. A portion (26a), a second opening (26b), and a flow path (28). In the joint part (25), the distance between the central axis (CF) on the second opening part (26b) side and the central axis (CC) on the first opening part (26a) side is the second opening part (26b). It is longer than the distance between the central axis (CF) on the side and the central axis (CF) on the first opening (26a) side. Further, the distance between the central axis (CF) on the first opening (26a) side and the central axis (CC) on the second opening (26b) side is the central axis on the first opening (26a) side ( CF) and the distance between the second opening (26b) side central axis (CF).

Description

  The present invention relates to a heat exchanger, an air conditioner including the heat exchanger, and a method for manufacturing the heat exchanger, and in particular, a heat exchanger to which a flat tube is applied as a heat transfer tube, and an air conditioner including the heat exchanger. And a method of manufacturing the heat exchanger.

  The heat exchanger of the outdoor unit used for the air conditioner includes a heat exchanger in which a heat transfer tube through which a refrigerant flows is arranged so as to penetrate plate-like fins arranged at intervals. Such a heat exchanger is called a finned tube heat exchanger. In this type of heat exchanger, there is a heat exchanger in which a flat tube having a flat cross-sectional shape with a flat cross-sectional shape is used as a heat transfer tube so that heat exchange is efficiently performed.

  In such a flat tube, a plurality of flat tubes in which the long diameter of the flat cross-sectional shape is arranged along the air flow direction are arranged at a distance from each other in the direction of the short diameter of the flat cross-sectional shape. In addition, with respect to the plurality of flat tubes (first row), a plurality of other flat tubes (second row) are arranged at a distance in the long diameter direction of the flat cross-sectional shape. Each of the flat tubes in the first row and each of the corresponding flat tubes in the second row are connected by a joint portion.

  While the refrigerant flows through the flat tubes located in the first row and the flat tubes located in the second row via the joint portion, heat exchange is performed between the refrigerant and the air. In addition, there exists patent document 1 as an example of the patent document which disclosed such a heat exchanger.

JP 2013-29243 A

  As a heat exchanger, a heat exchanger using a flat tube is required to more efficiently perform heat exchange between a refrigerant and air.

  The present invention has been made as part of such development, and one object is to provide a heat exchanger that can further improve heat exchange, and the other object is such heat exchange. It is providing the air conditioner provided with the apparatus, and the other objective is to provide the manufacturing method of such a heat exchanger.

  The heat exchanger according to the present invention includes a first flat tube, a second flat tube, and a joint portion. The first flat tube has a flat cross-sectional shape having a major axis and a minor axis. The second flat tube has a flat cross-sectional shape and is spaced from the first flat tube in the direction of the major axis. The joint portion connects the first flat tube and the second flat tube. The joint portion includes a first opening, a second opening, and a flow path. The first opening has a first cross-sectional shape corresponding to the flat cross-sectional shape and communicates with the first flat tube. The second opening is spaced from the first opening in the direction of the major axis, has a second cross-sectional shape corresponding to the flat cross-sectional shape, and communicates with the second flat tube. The flow path has a circular cross-sectional shape, is connected to the first opening and the second opening, and allows the first opening and the second opening to communicate with each other. An axis that passes through the center of the second cross-sectional shape at the first position where the flow path and the second opening are connected and is parallel to the direction in which the second flat tube extends is defined as the first central axis, and the flow path and the first An axis parallel to the direction in which the first flat tube extends through the center of the circular cross-sectional shape at the second position where the opening is connected is the second central axis, and the center of the first cross-sectional shape at the second position is The axis parallel to the direction in which the first flat tube extends is taken as the third central axis. Then, the first distance between the first central axis and the second central axis is longer than the second distance between the first central axis and the third central axis.

The air conditioner which concerns on this invention is an air conditioner provided with the heat exchanger mentioned above.
The manufacturing method of the heat exchanger according to the present invention includes the following steps. A plurality of first flat tubes each having a flat cross-sectional shape having a long diameter and a short diameter are prepared, and a plurality of second flat tubes each having a flat cross-sectional shape are prepared. Each of the plurality of first flat tubes is disposed at a distance from each other in the minor axis direction. Each of the plurality of second flat tubes is arranged with a distance in the direction of the short diameter, and is arranged with a distance in the direction of the long diameter with respect to each of the plurality of first flat tubes. A first opening having a first cross-sectional shape corresponding to the flat cross-sectional shape, a second opening having a second cross-sectional shape corresponding to the flat cross-sectional shape, and the first opening and the second opening. A joint portion having a flow path having a circular cross-sectional shape is formed. With respect to the first flat tube and the second flat tube, each of the plurality of first flat tubes and the plurality of second flat tubes disposed at a distance in the major axis direction with respect to each of the plurality of first flat tubes. Connect joints to each of the tubes. The assembled plurality of first flat tubes, the plurality of second flat tubes, and the plurality of joint portions are brazed. In the step of forming the joint portion, an axis parallel to the direction in which the second flat tube extends passes through the center of the second cross-sectional shape at the first position where the flow path and the second opening are connected. An axis that passes through the center of the circular cross-sectional shape at the second position where the flow path and the first opening are connected, and that is parallel to the direction in which the first flat tube extends, is the second central axis, and the second position If the third central axis is an axis that passes through the center of the first cross-sectional shape and is parallel to the direction in which the first flat tube extends, the first distance between the first central axis and the second central axis is: It is formed to be longer than the second distance between the first central axis and the third central axis.

  According to the heat exchanger according to the present invention, the first opening, the second opening, and the flow path are formed in the joint portion so that the first distance is longer than the second distance. Thereby, heat exchange can be efficiently performed with respect to any one of the cooling operation and the heating operation.

With the air conditioner according to the present invention, energy efficiency can be increased.
According to the manufacturing method of the heat exchanger which concerns on this invention, the heat exchanger provided with the joint part in which heat exchange is performed efficiently can be manufactured.

It is a figure which shows the refrigerant circuit of the air conditioner provided with the heat exchanger based on Embodiment 1 of this invention. In the embodiment, it is a perspective view which shows the outdoor unit provided with the heat exchanger which has a joint part. In the same embodiment, it is a partial expansion perspective view which shows a joint part and its peripheral part. In the embodiment, it is an expansion perspective view which shows a joint part. FIG. 5 is a partially enlarged cross-sectional view taken along a cross-sectional line VV shown in FIG. 4 in the same embodiment. FIG. 5 is a partially enlarged cross-sectional view taken along a cross-sectional line VI-VI shown in FIG. In the same embodiment, it is a partial enlarged plan view for demonstrating the arrangement | positioning relationship between a flat tube and a joint part. In the embodiment, it is a perspective view for demonstrating the flow of the refrigerant | coolant in the heat exchanger at the time of carrying out air_conditioning | cooling operation of the air conditioner. In the same embodiment, it is a partial enlarged plan view for explaining the flow of the refrigerant in the joint portion and its periphery when the air conditioner is in a cooling operation. FIG. 10 is an enlarged cross-sectional view taken along a cross-sectional line XX shown in FIG. 9 in the same embodiment. In the embodiment, it is a perspective view for demonstrating the flow of the refrigerant | coolant in the heat exchanger at the time of carrying out heating operation of the air conditioner. In the same embodiment, it is a partial enlarged plan view for explaining the flow of the refrigerant in the joint portion and its periphery when the air conditioner is in a heating operation. FIG. 13 is an enlarged cross-sectional view taken along a cross-sectional line XIII-XIII shown in FIG. 12 in the same embodiment. It is a perspective view which shows 1 process of the manufacturing method of the heat exchanger which concerns on Embodiment 2 of this invention. FIG. 15 is a perspective view showing a step performed after the step shown in FIG. 14 in the same embodiment. FIG. 16 is a perspective view showing a step performed after the step shown in FIG. 15 in the same embodiment. FIG. 17 is a partial perspective view showing a process performed after the process shown in FIG. 16 in the same embodiment. FIG. 18 is a partial perspective view illustrating a process performed after the process illustrated in FIG. 17 in the embodiment. FIG. 19 is a perspective view showing a step performed after the step shown in FIG. 18 in the same embodiment. In the same embodiment, it is a partial expansion perspective view which shows 1 process of the manufacturing method which concerns on a modification. FIG. 21 is a partially enlarged perspective view showing a process performed after the process shown in FIG. 20 in the same embodiment. FIG. 22 is a perspective view showing a step performed after the step shown in FIG. 21 in the same embodiment. In the same embodiment, it is a partial expansion perspective view which shows 1 process of the manufacturing method which concerns on another modification. FIG. 24 is a partially enlarged perspective view showing a process performed after the process shown in FIG. 23 in the embodiment.

Embodiment 1
First, a refrigerant circuit of an air conditioner (or air conditioning refrigeration apparatus) to which a heat exchanger is applied will be described. As shown in FIG. 1, the refrigerant circuit of the air conditioner 1 includes a compressor 3, a condensation heat exchanger 7 (5), a main throttle device 11, an evaporating heat exchanger 9 (5), blowers 8a and 10a, and a motor 8b. 10b. When the air conditioner 1 is in a cooling operation, the condensation heat exchanger 7 becomes a heat exchanger 5 mounted on the outdoor unit, and the evaporating heat exchanger 9 becomes a heat exchanger mounted on the indoor unit. On the other hand, when the air conditioner 1 is operated for heating, the evaporative heat exchanger 9 becomes the heat exchanger 5 mounted on the outdoor unit, and the condensing heat exchanger 7 becomes the heat exchanger mounted on the indoor unit. In the refrigerant circuit, for example, a refrigerant such as R410A, R32, HFO-1234yf, or the like is used as the refrigerant.

  Next, the structure of the heat exchanger 5 mounted on the outdoor unit as the condensation heat exchanger 7 or the evaporative heat exchanger 9 will be described. As shown in FIGS. 2 and 3, the plurality of plate-like fins 21 that are spaced apart from each other have a flat cross-sectional shape (see FIG. 17) having a major axis LR and a minor axis SR as heat transfer tubes. A plurality of first flat tubes 23a and second flat tubes 23b are disposed so as to penetrate from one to the other.

  Each of the plurality of first flat tubes 23a is disposed at a distance from each other in the minor axis direction. The plurality of first flat tubes 23a become the first flat tubes 23a in the first row 5a. In addition, each of the plurality of second flat tubes 23b is spaced apart from each other in the minor axis direction, and is disposed at a distance in the major axis direction from each of the plurality of first flat tubes 23a. The plurality of second flat tubes 23b become the second flat tubes 23b in the second row 5b.

  Blowers 8a and 10a are arranged so as to face the second flat tubes 23b in the second row. The first flat tubes 23a in the first row 5a are arranged on the windward side. The second flat tubes 23b in the second row 5b are arranged on the leeward side. Each of the plurality of first flat tubes 23 a protruding from one of the plurality of fins 21 and each of the corresponding plurality of second flat tubes 23 b are connected by a joint portion 25.

  Next, the joint part 25 will be described. As shown in FIGS. 4, 5, and 6, the joint portion 25 includes a first opening 26 a, a second opening 26 b, and a flow path 28. Each of the first opening 26a and the second opening 26b is a flat type having a long diameter LL and a short diameter LS corresponding to the flat cross-sectional shapes of the first flat tube 23a and the second flat tube 23b (see FIG. 17). It has a cross-sectional shape 27. The flow path 28 has a circular cross-sectional shape 29 and is formed so as to draw a substantially semicircle.

  The first opening 26a is connected to the first flat tube 23a and communicates with the first flat tube 23a. The second opening 26b is connected to the second flat tube 23b and communicates with the second flat tube 23b. The flow path 28 is connected to the first opening 26a and the second opening 26b, and allows the first opening 26a and the second opening 26b to communicate with each other. As will be described later, the joint portion 25 is formed by joining (caulking) two pressed aluminum plates to each other.

  Here, as shown in FIG. 7, the first flat tube 23 a (the first flat tube 23 a (the first opening) passes through the center MC of the circular cross-sectional shape 29 at the position where the flow path 28 and the first opening 26 a (the second opening 26 b) are connected. An axis parallel to the direction in which the 2 flat tubes 23b) extend is defined as a central axis CC. In addition, an axis parallel to the direction in which the first flat tube 23a (second flat tube 23b) extends through the center MF of the flat cross-sectional shape 27 at that position is defined as a central axis CF. The center MF of the flat cross-sectional shape 27 refers to an intersection where the vertical bisector of the long diameter LL (see FIG. 4) and the vertical bisector of the short diameter LS (see FIG. 4) intersect. It is not intended to be a geometrically exact intersection and includes manufacturing errors. The same applies to the center MC of the circular cross-sectional shape 29.

  Then, in the heat exchanger 5, the distance between the central axis CF on the second opening 26b side and the central axis CC on the first opening 26a is equal to the central axis CF on the second opening 26b side and the first opening. It is longer than the distance between the central axis CF on the part 26a side. The distance between the central axis CF on the first opening 26a side and the central axis CC on the second opening 26b side is equal to the central axis CF on the first opening 26a side and the central axis on the second opening 26b side. Longer than the distance to the CF. Specifically, as will be described later, on the first row 5a side located on the windward side, the center axis CC is located on the windward side than the center axis CF. On the second row 5b side located on the leeward side, the central axis CC is located on the leeward side with respect to the central axis CF.

  On the other side of the plurality of fins 21, the distribution header 15 is disposed on the leeward side (first row 5a side), and the gas header 13 is disposed on the leeward side (second row 5b side). The heat exchanger 5 according to Embodiment 1 is configured as described above.

  Next, as an operation of air conditioning to which the heat exchanger 5 described above is applied, first, a cooling operation will be described based on the refrigerant circuit shown in FIG. In the cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor is sent to the condensation heat exchanger 7. In the condensation heat exchanger 7, the high-temperature and high-pressure gas refrigerant is liquefied while dissipating heat to the surroundings, and becomes a low-temperature and high-pressure liquid refrigerant. The low-temperature and high-pressure liquid refrigerant is reduced in pressure by the main throttle device 11 and becomes a low-temperature and low-pressure liquid refrigerant. The low-temperature and low-pressure liquid refrigerant is sent to the evaporative heat exchanger 9. In the evaporative heat exchanger 9, the low-temperature and low-pressure liquid refrigerant is vaporized while taking away the surrounding heat, and becomes a low-pressure gas refrigerant. The low-pressure gas refrigerant is sent to the compressor and becomes a high-temperature and high-pressure gas refrigerant. Thereafter, this cycle is repeated.

  In the cooling operation, the heat exchanger 5 is mounted on the outdoor unit as the condensation heat exchanger 7. Next, the flow of the refrigerant in the heat exchanger 5 (condensing heat exchanger 7) will be described. As shown in FIG. 8, in the heat exchanger 5, as the blower 8a rotates, the air passes through the heat exchanger 5 from the first row 5a side to the second row 5b side as shown by the arrow YW. Will flow.

  The high-temperature and high-pressure gas refrigerant sent from the compressor firstly connects the second flat tubes 23b in the second row 5b located on the leeward side from the side where the gas header 13 is arranged as shown by the arrow YC. It flows toward the side where 25 is arranged. In the joint portion 25, the refrigerant flowing through the second flat tube 23b passes through the second opening 26b, the flow path 28, and the first opening 26a, and the first flat tube 23a in the first row 5a located on the windward side. Sent to.

  The refrigerant sent to the first flat tube 23a flows through the first flat tube 23a toward the side where the distribution header 15 is disposed, as indicated by an arrow YC. While the high-temperature and high-pressure gas refrigerant flows through the second flat tube 23b and the first flat tube 23a, heat exchange is performed with the air passing through the heat exchanger 5 to become a low-temperature and high-pressure liquid refrigerant.

  Next, the flow of the refrigerant in the joint portion 25 will be described. As shown in FIG. 9, the high-temperature and high-pressure gas refrigerant is gradually condensed and liquefied while flowing through the second flat tube 23 b on the leeward side, and the gas refrigerant and the liquid are supplied to the second opening 26 b of the joint portion 25. A two-phase refrigerant flows into the refrigerant. The refrigerant that has flowed into the second opening 26b flows through the flow path 28 and into the first opening 26a.

  At this time, the liquid refrigerant out of the two-phase state refrigerant once flows into the windward side of the first opening 26a due to inertial force, and further flows on the inner wall surface of the first opening 26a due to the inertial force. Thus, it flows into the leeward side of the first opening 26a (see the arrow indicating the flow). For this reason, the distribution of the liquid refrigerant 41 immediately before flowing into the first flat tube 23a is biased toward the leeward side. As the liquid refrigerant 41 is biased toward the leeward side, the gas refrigerant is unevenly distributed on the windward side.

  Next, as shown in FIG. 10, the gas refrigerant is mainly distributed on the leeward side and the liquid refrigerant 41 is mainly distributed on the leeward side, and the refrigerant is supplied to the first flat tube 23a provided with the refrigerant passage 24. Flows in. Since the heat flow rate on the windward side is larger than the heat flow rate on the leeward side, the gas refrigerant distributed unevenly on the windward side is efficiently condensed and liquefied while flowing through the first flat tube 23a. Thereby, at the distribution header 15 side (exit) of the heat exchanger 5, the dryness of the refrigerant becomes substantially uniform in the direction of the long diameter of the first flat tube 23a. Thus, the low-temperature and high-pressure liquid refrigerant condensed and liquefied is sent out from the heat exchanger 5.

  Next, the heating operation will be described. The flow of the refrigerant in the refrigerant circuit in the heating operation is as described for the cooling operation. In the case of heating operation, the heat exchanger 5 is mounted on the outdoor unit as the evaporating heat exchanger 9.

  Next, the flow of the refrigerant in the heat exchanger 5 (evaporation heat exchanger 9) will be described. As shown in FIG. 11, in the heat exchanger 5, as the blower 10a rotates, the air passes through the heat exchanger 5 from the first row 5a side to the second row 5b side as shown by the arrow YW. Will flow.

  In the liquid refrigerant that has become low-temperature and low-pressure through the main throttle device 11, first, the distribution header 15 is arranged in the first flat tubes 23a in the first row 5a located on the windward side as indicated by the arrow YH. It flows from the side toward the side where the joint part 25 is disposed. In the joint portion 25, the refrigerant flowing through the first flat tube 23a passes through the first opening 26a, the flow path 28, and the second opening 26b, and the second flat tubes 23b in the second row 5b located on the leeward side. Sent to.

  The refrigerant sent to the second flat tube 23b flows through the second flat tube 23b toward the side where the gas header 13 is disposed, as indicated by an arrow YH. While the low-temperature and low-pressure liquid refrigerant flows through the first flat tube 23a and the second flat tube 23b, heat exchange is performed with the air passing through the heat exchanger 5 to become a low-pressure gas refrigerant.

  Next, the flow of the refrigerant in the joint portion 25 will be described. As shown in FIG. 12, the low-temperature and low-pressure liquid refrigerant gradually evaporates and vaporizes while flowing through the first flat tube 23a on the windward side, and gas refrigerant and liquid are supplied to the first opening 26a of the joint portion 25. A two-phase refrigerant flows into the refrigerant. The refrigerant that has flowed into the first opening 26a flows through the flow path 28 and into the second opening 26b.

  At this time, the liquid refrigerant out of the two-phase state refrigerant once flows into the leeward side of the second opening 26b due to the inertial force, and further flows along the inner wall surface of the second opening 26b due to the inertial force. Thus, it flows into the windward side of the second opening 26b (see the arrow indicating the flow). For this reason, the distribution of the liquid refrigerant 41 immediately before flowing into the second flat tube 23b is a distribution biased toward the windward side. As the liquid refrigerant 41 is biased toward the windward side, the gas refrigerant is unevenly distributed on the leeward side.

  Next, as shown in FIG. 13, the liquid refrigerant 41 is mainly distributed on the leeward side, and the gas refrigerant is mainly distributed on the leeward side, and the refrigerant is supplied to the second flat tube 23b provided with the refrigerant passage 24. Flows in. Since the heat flow rate on the windward side is larger than the heat flow rate on the leeward side, the liquid refrigerant 41 distributed unevenly on the windward side is efficiently evaporated and vaporized while flowing through the second flat tube 23b. Thereby, on the gas header 13 side (exit) of the heat exchanger 5, the dryness of the refrigerant becomes substantially uniform in the direction of the major axis of the second flat tube 23b. Thus, the low-pressure gas refrigerant evaporated and vaporized is sent out from the heat exchanger 5.

  On the windward first row 5a side in the joint portion 25 of the heat exchanger 5 described above, the central axis CC of the flow path 28 is located on the windward side with respect to the central axis CF of the first opening 26a. Therefore, when the heat exchanger 5 is used as a condensation heat exchanger (cooling operation), the refrigerant passes from the second flat tube 23b on the leeward side through the second opening 26b and the flow path 28 of the joint portion 25. When flowing into the first opening 26a, the liquid refrigerant can be biased to the leeward side by inertial force.

  Thereby, the liquid refrigerant flows into the first flat tube 23a on the leeward side in a state where the liquid refrigerant is biased toward the leeward side and the gas refrigerant is biased toward the leeward side, and in the first flat tube 23a, the heat flow rate is higher than that on the leeward side. On the large windward side, the gas refrigerant can be efficiently condensed and liquefied. As a result, heat exchange is performed more efficiently than when the gas refrigerant (or liquid refrigerant) flows into the first flat tube 23a with a substantially uniform distribution in the direction of the long diameter of the first flat tube 23a, The heat exchange performance as a heat exchanger can be improved. The heat exchange performance is the product of the heat transfer area and the heat passage rate, and the higher this value, the higher the heat exchange performance.

  Further, on the second row 5b side on the leeward side in the joint portion 25 of the heat exchanger 5 described above, the central axis CC of the flow path 28 is located on the leeward side with respect to the central axis CF of the second opening 26b. For this reason, when the heat exchanger 5 is used as an evaporative heat exchanger (heating operation), the refrigerant passes from the first flat tube 23a on the windward side through the first opening 26a and the flow path 28 of the joint portion 25. When flowing into the second opening 26b, the liquid refrigerant can be biased to the windward side by the inertial force.

  As a result, the liquid refrigerant flows into the second flat tube 23b on the leeward side in a state where the liquid refrigerant is biased toward the leeward side and the gas refrigerant is biased toward the leeward side. In the second flat tube 23b, the heat flow rate is higher than that on the leeward side. On the large windward side, the liquid refrigerant can be efficiently evaporated and vaporized. As a result, the liquid refrigerant (or gas refrigerant) exchanges heat more efficiently than when flowing into the second flat tube 23b with a substantially uniform distribution in the direction of the major axis of the second flat tube 23b, The heat exchange performance as a heat exchanger can be improved.

  In this way, an air conditioner with high energy efficiency is realized by applying the heat exchanger 5 including the joint portion 25 described above to one or both of the condensation heat exchanger and the evaporating heat exchanger. be able to.

Here, the heating energy efficiency is expressed by the following equation:
Heating energy efficiency = condensation heat exchanger (indoor) capacity (watts) / total input (watts)
Represented by

The cooling energy efficiency is given by
Cooling energy efficiency = evaporative heat exchanger (indoor) capacity (watts) / total input (watts)
Represented by

Embodiment 2
Here, an example of the manufacturing method of the heat exchanger provided with the joint part described in the first embodiment will be described.

  First, as shown in FIG. 14, for example, two aluminum plates 31 a and 31 b are prepared as metal plates (plate-like bodies) cut into desired dimensions. Each of the aluminum plates 31a and 31b is formed with a protruding portion 32 serving as a crimped portion.

  Next, as shown in FIG. 15, by pressing each of the aluminum plates 31a and 31b, the first recess 33a is formed in the aluminum plate 31a, and the second recess 33b is formed in the aluminum plate 31b. To do. Here, the first recess 33a and the second recess 33b are formed in a shape that becomes the first opening 26a, the second opening 26b, and the flow path 28 in a state where the aluminum plate 31a and the aluminum plate 31b are combined. (See FIG. 16). That is, as shown in FIG. 7, the first concave portion 33a and the second concave portion 33b are formed so that the central axis CC and the central axis CF are shifted from each other in the direction of the long diameter LL (see FIG. 4). become.

  Next, as shown in FIG. 16, with the first concave portion 33a and the second concave portion 33b facing each other, the aluminum plate 31a and the aluminum plate 31b are aligned, and the protruding portion 32 is bent and caulked to each other (caulking portion). 35). The first opening 26a, the flow path 28, and the second opening 26b are formed by the first recess 33a and the second recess 33b facing each other. Thus, the joint portion 25 is formed.

  Next, the joint portion 25 is connected to the first flat tube and the second flat tube. As shown in FIG. 17, the first flat tube 23a is fitted with the first opening 26a with respect to the first flat tube 23a and the second flat tube 23b that penetrate the plurality of fins 21 and protrude from one side, respectively. The joint portion 25 is pushed toward the first flat tube 23a (second flat tube 23b) in a state where the second opening 26b is aligned with the second flat tube 23b. Thus, as shown in FIG. 18, the joint portion 25 is connected to the first flat tube 23a and the second flat tube 23b, and the first flat tube 23a and the second flat tube 23b are connected.

  Hereinafter, by repeating this step, as shown in FIG. 19, each of the plurality of first flat tubes 23a penetrating the plurality of fins 21 and projecting from one side, and each of the corresponding plurality of second flat tubes 23b, respectively. Are connected by the joint portion 25.

  Next, flux is applied to the plurality of fins 21, the first flat tube 23a, the second flat tube 23b, and the joint portion 25 (assembly) assembled by, for example, a spray method. Next, the assembly to which the flux is applied is placed in a furnace (not shown). Next, brazing is performed by performing a heat treatment on the assembly under a predetermined temperature condition.

  After the temperature in the furnace has dropped, the assembly is removed. Thus, the heat exchanger 5 provided with the joint portion 25 is completed. Then, the outdoor unit of an air conditioner is completed by assembling the completed heat exchanger 5 in a predetermined housing (see FIG. 2).

  As described above, in the joint portion 25 of the heat exchanger 5, the distance between the central axis CF on the second opening 26b side and the central axis CC on the first opening 26a side is set on the second opening 26b side. It is longer than the distance between the central axis CF and the central axis CF on the first opening 26a side. The distance between the central axis CF on the first opening 26a side and the central axis CC on the second opening 26b side is equal to the central axis CF on the first opening 26a side and the central axis on the second opening 26b side. Longer than the distance to the CF. That is, the central axis CC and the central axis CF are shifted from each other in the direction of the major axis LL (see FIG. 4).

  In the heat exchanger manufacturing method described above, the joint portion 25 having the first opening portion 26a, the flow path 28 and the second opening portion 26b is formed by pressing the two aluminum plates 31a and 31b. Formed (see FIGS. 14 to 16). Thereby, the 1st recessed part 33a and the 2nd recessed part 33b used as the 1st opening part 26a, the flow path 28, and the 2nd opening part 26b which have the said arrangement | positioning relationship can be formed comparatively easily.

(Modification)
In the manufacturing method described above, the case where the plurality of joint portions are connected to the corresponding first flat tube and the second flat tube one by one has been described, but the plurality of joint portions may be connected together. Good.

  As shown in FIG. 20, a holding member 43 that holds a plurality of joint portions 25 at intervals in the minor axis direction is prepared. A plurality of slits 43 a are formed in the holding member 43 at intervals in the longitudinal direction. Next, the joint portion 25 is fitted into each of the plurality of slits 43a.

  Thus, as shown in FIG. 21, the plurality of joint portions 25 are held by the holding member 43 while being spaced apart from each other. Next, as shown in FIG. 22, the plurality of held joint portions 25 are collectively connected to the corresponding first flat tube 23a and second flat tube 23b.

  In this method, the plurality of joint portions 25 are collectively handled as compared with a case where the plurality of joint portions 25 are connected one by one to the corresponding first flat tube 23a and second flat tube 23b. It can connect to the 1st flat tube 23a and the 2nd flat tube 23b, and efficiency improvement of the assembly operation of the heat exchanger 5 can be achieved.

  In addition, in order to hold | maintain several joint parts more firmly, as shown in FIG. 23, you may form the slit 25a also in the joint part 25. As shown in FIG. As shown in FIG. 24, the joint portion 25 is fitted into the slit 43a of the holding member 43, and the holding member 43 is fitted into the slit 25a of the joint portion 25, so that the plurality of joint portions are more firmly secured by the holding member. Retained. Thereby, when connecting the some joint part 25 to a 1st flat tube and a 2nd flat tube, positioning becomes easy.

  In the modification, the case where the plurality of joint portions 25 are held by one holding member 43 has been described as an example, but may be held by using two or more holding members. In this case, by holding the portion in the vicinity of the first opening and the portion in the vicinity of the second opening, positioning is performed when connecting the plurality of joint portions 25 to the first flat tube and the second flat tube. Is even easier.

  The case where two aluminum plates are formed by pressing as the joint portion of the heat exchanger 5 described above has been described. As a manufacturing method of the joint portion, if the first opening, the flow path, and the second opening can be formed with an arrangement relationship in which the central axis CC and the central axis CF are shifted from each other in the direction of the long diameter LL, The method is not limited to the press working method. For example, after the first opening, the flow path, and the second opening are formed as separate members, the first opening, the flow path, and the second opening may be connected by brazing or the like so that the arrangement relationship is established. Good.

  Moreover, although the heat exchanger 5 provided in the outdoor unit has been described as an example of the heat exchanger 5 including the joint portion 25, it can also be applied as a heat exchanger mounted in the indoor unit. . Furthermore, refrigeration oils such as mineral oils, alkylbenzene oils, ester oils, ether oils, fluorine oils, etc. can be used as the refrigeration oils, regardless of whether the refrigerant or the refrigeration oil is insoluble or insoluble. The effect by can be acquired. In addition to heat exchange between the refrigerant and the air, the present invention can also be applied to heat exchange between the refrigerant and a gas other than air, a liquid, or a gas-liquid mixed flow.

  Furthermore, in each embodiment mentioned above, it demonstrated taking the case of the heat exchanger 5 provided with the fin 21 as an example. The heat exchanger may be a finless heat exchanger (not shown) that does not include fins. In the case of a finless heat exchanger, when connecting the joint portion to the first flat tube and the second flat tube, the first flat tube and the second flat tube are connected to a predetermined position by a holding member or the like (not shown). What is necessary is just to connect a joint part in the state hold | maintained to.

  The embodiment disclosed this time is an example, and the present invention is not limited to this. The present invention is defined by the terms of the claims, rather than the scope described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  INDUSTRIAL APPLICABILITY The present invention is effectively used for a heat exchanger, an air conditioner, a heat pump device, etc. to which a flat tube is applied as a heat transfer tube of an air conditioner.

  DESCRIPTION OF SYMBOLS 1 Air conditioner, 3 Compressor, 5 Heat exchanger, 5a 1st row, 5b 2nd row, 7 Condensation heat exchanger, 8a Blower, 8b Motor, 9 Evaporation heat exchanger, 10a Blower, 10b Motor, 11 Main Throttle device, 13 Gas header, 15 Distribution header, 21 Fin, 23, 23a, 23b Flat tube, 24 Refrigerant passage, 25 Joint part, 25a Slit, 26a First opening part, 26b Second opening part, 27 Flat cross-sectional shape, 28 channel, 29 circular cross-sectional shape, 31a, 31b aluminum plate, 32 protrusion, 33a first recess, 33b second recess, 35 caulking part, 41 liquid refrigerant, 43 holding member, 43a slit, CC, CF central axis, LL, LR major axis, LS, SR minor axis, MC, MF center, YC, YH, YW Arrows.

Claims (11)

A first flat tube having a flat cross-sectional shape having a major axis and a minor axis;
A second flat tube having the flat cross-sectional shape and spaced from the first flat tube in the direction of the major axis;
A joint portion connecting the first flat tube and the second flat tube;
The joint part is
A first opening having a first cross-sectional shape corresponding to the flat cross-sectional shape and communicating with the first flat tube;
A second opening that is spaced apart from the first opening in a direction of the major axis, has a second cross-sectional shape corresponding to the flat cross-sectional shape, and communicates with the second flat tube;
A circular cross-sectional shape, connected to the first opening and the second opening, and a flow path that allows the first opening and the second opening to communicate with each other;
An axis parallel to the direction in which the second flat tube extends passes through the center of the second cross-sectional shape at the first position where the flow path and the second opening are connected, and the first central axis,
An axis parallel to the direction in which the first flat tube extends passes through the center of the circular cross-sectional shape at the second position where the flow path and the first opening are connected, and the second central axis.
When an axis parallel to the direction in which the first flat tube extends through the center of the first cross-sectional shape at the second position is a third central axis,
The heat exchanger, wherein a first distance between the first central axis and the second central axis is longer than a second distance between the first central axis and the third central axis. When an axis parallel to the direction in which the second flat tube extends through the center of the circular cross-sectional shape at the first position is a fourth central axis,
The heat exchanger according to claim 1, wherein a third distance between the third central axis and the fourth central axis is longer than a fourth distance between the third central axis and the first central axis. .   2. The heat exchanger according to claim 1, wherein in the joint portion, the first opening, the second opening, and the flow path are formed in a state where two plate-like materials are joined. A plurality of the first flat tubes are arranged in a manner of being spaced apart from each other in the direction of the minor axis,
A plurality of the second flat tubes are arranged in such a manner that they are spaced apart from each other in the direction of the short diameter and are spaced apart in the direction of the long diameter with respect to each of the plurality of first flat tubes,
A plurality of the joint portions are arranged in such a manner as to connect each of the plurality of first flat tubes and each of the corresponding plurality of second flat tubes adjacent to each other at a distance in the major axis direction. The heat exchanger according to claim 1.   The heat exchanger according to claim 4, further comprising a holding member that holds each of the plurality of joint portions arranged at intervals in the direction of the minor axis.   The heat exchanger according to claim 1, wherein a refrigerant inlet / outlet portion is disposed with respect to the first flat tube and the second flat tube.   An air conditioner comprising the heat exchanger according to claim 1. Preparing a plurality of first flat tubes each having a flat cross-sectional shape having a long diameter and a short diameter, and preparing a plurality of second flat tubes each having a flat cross-sectional shape;
Disposing each of the plurality of first flat tubes at a distance from each other in the direction of the minor axis;
And disposing each of the plurality of second flat tubes at a distance in the direction of the short diameter and disposing a distance in the direction of the long diameter with respect to each of the plurality of first flat tubes;
A first opening having a first cross-sectional shape corresponding to the flat cross-sectional shape, a second opening having a second cross-sectional shape corresponding to the flat cross-sectional shape, and the first opening and the second opening Forming a joint portion having a flow path having a circular cross-sectional shape connected to the portion;
Each of the plurality of first flat tubes, and each of the plurality of second flat tubes disposed at a distance in the major axis direction with respect to each of the plurality of first flat tubes. Connecting the
Brazing the assembled plurality of first flat tubes, the plurality of second flat tubes, and the plurality of joint portions;
In the step of forming the joint part,
An axis parallel to the direction in which the second flat tube extends through the center of the second cross-sectional shape at the first position where the flow path and the second opening are connected, is the first central axis, An axis passing through the center of the circular cross-sectional shape at the second position where the flow path and the first opening are connected and parallel to the direction in which the first flat tube extends is defined as the second central axis, and the second When an axis parallel to the direction in which the first flat tube extends through the center of the first cross-sectional shape at a position is the third central axis,
The first distance between the first central axis and the second central axis is formed so as to be longer than the second distance between the first central axis and the third central axis. Manufacturing method. In the step of forming the joint part,
When an axis parallel to the direction in which the second flat tube extends through the center of the circular cross-sectional shape at the first position is a fourth central axis,
The third distance between the third central axis and the fourth central axis is formed to be longer than the fourth distance between the third central axis and the first central axis. The manufacturing method of the heat exchanger of Claim 8. The step of forming the joint part includes
Preparing a first plate and a second plate,
Forming a first recess by pressing the first plate-like body;
Forming a second recess by pressing the second plate-like body;
Joining the first plate-like body and the second plate-like body in such a manner that the first recess and the second recess face each other,
In the step of forming the first recess and the step of forming the second recess, the first cross-sectional shape, the second cross-sectional shape, and the circular cross-section are in a state where the first concave portion and the second concave portion face each other. The method for manufacturing a heat exchanger according to claim 9, wherein the first recess and the second recess are formed in a form in which a shape is formed. The step of forming the joint portion includes a step of attaching a holding member that holds in advance the plurality of joint portions arranged at a distance in the direction of the minor axis,
The step of connecting the joint portions includes a step of connecting the plurality of joint portions held by the holding member to each of the corresponding first flat tube and the second flat tube. Manufacturing method of heat exchanger.

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