WO2024071025A1

WO2024071025A1 - Heat exchanger

Info

Publication number: WO2024071025A1
Application number: PCT/JP2023/034695
Authority: WO
Inventors: 起洋剛豊山; 好男織谷; 文奥野; 智彦坂巻; 将仁関谷; 貴也小田; 良広堤
Original assignee: ダイキン工業株式会社
Priority date: 2022-09-30
Filing date: 2023-09-25
Publication date: 2024-04-04
Also published as: JP2024054878A; JP7464872B1

Abstract

This heat exchanger, which comprises flat tubes and fins, suppresses a decline in heat exchange efficiency that could arise as a consequence of maintaining the pitch of fins. At least one fin pitch regulation part (340) is disposed in contact with adjacent fins (30) to regulate the fin pitch. For each of the fins (30), the fin pitch regulation part (340) is provided per N (N is an integer of 2 or greater) flat tubes. The fin pitch regulation part (340) of each of the fins (30) includes at least two raised sections (341) which are formed by cutting and raising, in two or more directions, a heat transfer section (330) of the fin (30), said section being located in an area other than a connection section (320).

Description

Heat exchanger

The present disclosure relates to a heat exchanger having multiple fins and multiple flat tubes.

Heat exchangers equipped with multiple flat tubes and multiple fins are used in outdoor units of air conditioners, etc. Patent Document 1 (JP 2012-163318 A) shows an example of an outdoor heat exchanger used in the outdoor unit of an air conditioner that is equipped with flat tubes and fins.

In the outdoor heat exchanger described in Patent Document 1, spacers attached to the fins abut against adjacent fins to maintain a predetermined distance between the fins. This predetermined distance between the fins is the fin pitch. However, placing spacers on the fins to ensure the fin pitch leads to a decrease in heat exchange efficiency. In particular, when the heat exchanger is required to be compact, such as when used in an indoor unit, the decrease in heat exchange efficiency due to the spacers becomes a problem.

Heat exchangers with flat tubes and fins face the challenge of suppressing the decrease in heat exchange efficiency that occurs when ensuring the fin pitch.

The heat exchanger of the first aspect is a heat exchanger that includes a plurality of fins and a plurality of flat tubes, and exchanges heat with air passing between the plurality of flat tubes and the plurality of fins in a first direction. Each fin includes a heat transfer portion having a plurality of through-holes, a communication portion, and one or more fin pitch determining portions. A plurality of flat tubes pass through the plurality of through-holes. The communication portion extends in a second direction intersecting the first direction without penetrating the plurality of flat tubes. The one or more fin pitch determining portions contact adjacent fins to determine the fin pitch. One fin pitch determining portion is provided for N (N is an integer of 2 or more) flat tubes in each fin. The fin pitch determining portion of each fin includes two or more raised portions formed by cutting and raising the heat transfer portion of each fin located in a position other than the communication portion in two or more directions.

In the heat exchanger of the first aspect, two or more raised portions of the fin pitch defining portion are cut and raised in two or more directions, so that gaps are created between the two or more raised portions, and it is possible to prevent at least one of the ventilation path and the drainage path from being narrowed by the fin pitch defining portion.

The heat exchanger of the second aspect is the heat exchanger of the first aspect, and the fin pitch determining portion includes three raised portions formed by cutting and raising the heat transfer portion of each fin located in a location other than the communication portion in three directions.

In the heat exchanger of the second aspect, three gaps are formed between the three rising parts, so that the fin pitch can be stably determined while preventing at least one of the ventilation path and the drainage path from being narrowed by the fin pitch determination part.

The heat exchanger of the third aspect is the heat exchanger of the first aspect, and the fin pitch determining portion includes four raised portions formed by cutting and raising the heat transfer portion of each fin located in a location other than the communication portion in four directions.

In the heat exchanger of the third aspect, four gaps are formed between the four rising parts, so that the ventilation path and the drainage path can be prevented from being narrowed by the fin pitch regulation part.

The heat exchanger of the fourth aspect is a heat exchanger of any one of the first aspect to the third aspect, in which the number of flat tubes is four or more, and one fin pitch regulation portion is provided for every four flat tubes.

In the heat exchanger of the fourth aspect, the reduction in the heat transfer coefficient caused by providing a fin pitch regulation portion in the heat transfer portion can be suppressed.

The heat exchanger of the fifth aspect is a heat exchanger of any one of the first aspect to the third aspect, in which the number of flat tubes is six or more, and one fin pitch regulation portion is provided for every six flat tubes.

In the heat exchanger of the fifth aspect, the reduction in the heat transfer coefficient caused by providing a fin pitch regulation portion in the heat transfer portion can be suppressed.

The heat exchanger of the sixth aspect is a heat exchanger of any one of the first aspect to the fifth aspect, in which the number of fin pitch defining portions in each fin is three or more. The three or more fin pitch defining portions in each fin are arranged so that the number of flat tubes between adjacent fin pitch defining portions is the same.

In the heat exchanger of the sixth aspect, the fin pitch regulation portion is arranged so that the points where the heat transfer coefficient decreases are arranged regularly, and the decrease in the overall heat transfer coefficient can be suppressed compared to when the points are arranged irregularly.

The heat exchanger of the seventh aspect is a heat exchanger of any one of the first to sixth aspects, in which each penetration portion of each fin has a first rising portion that rises along the corresponding flat tube and contacts the adjacent fin, and a second rising portion that rises along the corresponding flat tube and does not contact the adjacent fin.

In the heat exchanger of the seventh aspect, the first upright portion of the penetration portion comes into contact with the adjacent fin, so that buckling can be prevented from occurring when the flat tube is inserted.

The heat exchanger of the eighth aspect is any one of the heat exchangers of the first to seventh aspects, in which the air passing through in the first direction is indoor air that is heat exchanged in an indoor unit that performs indoor air conditioning.

The heat exchanger of the ninth aspect is a heat exchanger that includes a plurality of flat tubes and a plurality of fins. Each fin has a plurality of penetrations through which the plurality of flat tubes pass. Each penetration has a first upright portion that rises along the corresponding flat tube and contacts the adjacent fin.

In the heat exchanger of the ninth aspect, when there is another part that determines the fin pitch other than the first standing part, the first standing part can suppress buckling and fin crushing when the flat tubes are inserted, and can help ensure the fin pitch by the other part that determines the fin pitch.

The heat exchanger of the tenth aspect is the heat exchanger of the ninth aspect, in which the first upright portion is provided on only one of the two side surfaces of each flat tube in the longitudinal direction of each fin.

In the heat exchanger of the tenth aspect, the first raised portion is provided on only one of the two side surfaces of the flat tube, so the height of the first raised portion can be increased to a height close to the thickness of the flat tube, compared to when the first raised portion is provided on both sides.

The heat exchanger of the eleventh aspect is the heat exchanger of the ninth or tenth aspect, and each penetration portion has, as a portion other than the first upright portion, a second upright portion that rises along the corresponding flat tube and does not contact the adjacent fin. The first upright portion rises higher than the second upright portion.

1 is a conceptual diagram showing an outline of the configuration of an air conditioner. FIG. 1 is a diagram showing the external appearance of an indoor unit and an outdoor unit of an air conditioner. FIG. 2 is a plan view of an indoor heat exchanger in the indoor unit. 4 is a cross-sectional view of the indoor unit taken along line II in FIG. 3. FIG. 2 is a perspective view of a first heat exchange section of the indoor heat exchange section. 6 is a partially enlarged cross-sectional view showing a cross section of the first heat exchanger portion of FIG. 5 taken along plane B. 4 is a plan view of the first heat exchange section as viewed in the thickness direction of the flat tube. FIG. FIG. 4 is a partially enlarged plan view showing a portion of the fin. 10 is a partially enlarged perspective view showing a part of a fin on which a fin pitch determining portion is not formed. FIG. 4 is a partially enlarged perspective view showing a part of a fin on which a fin pitch defining portion is formed; FIG. 13 is a graph showing the air-side heat transfer coefficient of several types of fins. FIG. 12 is a partially enlarged plan view showing an example of the configuration of a fin corresponding to the graph in FIG. 11 . 12 is a partially enlarged plan view showing another example of the configuration of the fin corresponding to the graph in FIG. 11 . 12 is a partially enlarged plan view showing another example of the fin configuration corresponding to the graph in FIG. 11 . FIG. 12 is a partially enlarged plan view showing another example of the fin configuration corresponding to the graph in FIG. 11 . FIG. FIG. 11 is a cross-sectional view showing another example of the indoor unit. FIG. 11 is a cross-sectional view showing another example of the indoor unit. FIG. 11 is a cross-sectional view showing another example of the indoor unit. FIG. 13 is a partially enlarged plan view showing the configuration of a fin according to modification B.

(1) Overall Configuration As shown in Fig. 1, the heat exchanger according to the embodiment is, for example, an indoor heat exchanger 1 that is applied to an indoor unit 110 of an air conditioner 100. The air conditioner 100 includes the indoor unit 110 and an outdoor unit 120. The indoor unit 110 is connected to the outdoor unit 120 by connecting

pipes

131 and 132.

As shown in FIG. 2, the indoor unit 110 includes a casing 111 and an indoor fan 112 in addition to the indoor heat exchanger 1. The indoor unit 110 is a wall-mounted type that is installed by hanging it on the wall WL in the room RM. The indoor unit 110 has an approximately rectangular parallelepiped appearance. The casing 111 mainly constitutes the outer surface of the indoor unit 110. The casing 111 houses the indoor heat exchanger 1 and the indoor fan 112 inside. The casing 111 has an intake port 113 that allows indoor air to flow into the inside of the casing 111, and an outlet port 114 from which air that has exchanged heat with the refrigerant in the indoor heat exchanger 1 is blown out. The position (rotation angle) of the flap 115 is controlled. By changing the position of the flap 115, the opening degree of the outlet port 114 and the wind direction of the airflow blown out from the outlet port 114 are adjusted.

The outdoor unit 120 is installed outside the room RM, for example, on the roof of a building or near the exterior wall of the building. The outdoor unit 120 has a compressor 122, a four-way valve 123, an outdoor heat exchanger 124, an expansion valve 125, and an outdoor fan 126.

Compressor 122 draws in low-pressure refrigerant from an intake port, compresses it to high pressure, and then discharges it from a discharge port. Compressor 122 is, for example, a positive displacement compressor whose capacity can be changed by changing the rotation speed of a built-in motor. Four-way valve 123 has a first port P1, a second port P2, a third port P3, and a fourth port P4.

The four-way valve 123 switches the direction of refrigerant flow by switching between a first state (a state shown by a dashed line in FIG. 2) and a second state (a state shown by a solid line in FIG. 2). In the first state, the first port P1 and the fourth port P4 communicate with each other, and the second port P2 and the third port P3 communicate with each other. In the second state, the first port P1 and the second port P2 communicate with each other, and the third port P3 and the fourth port P4 communicate with each other. The first port P1 is connected to the discharge port of the compressor 122. The second port P2 is connected to the gas side inlet/outlet of the outdoor heat exchanger 124. The third port P3 is connected to the suction port of the compressor 122. The fourth port P4 is connected to the connecting pipe 132.

The outdoor heat exchanger 124 is a heat exchanger that exchanges heat between the refrigerant and the outside air. The liquid side inlet and outlet of the outdoor heat exchanger 124 are connected to the expansion valve 125. The gas side inlet and outlet of the outdoor heat exchanger 124 are connected to the second port P2 of the four-way valve 123.

The expansion valve 125 reduces the pressure of the refrigerant. The expansion valve 125 is provided between the connecting pipe 131 and the liquid side of the outdoor heat exchanger 124. The expansion valve 125 is, for example, an electric expansion valve whose opening degree can be controlled.

The compressor 122, four-way valve 123, outdoor heat exchanger 124, expansion valve 125, and indoor heat exchanger 1 form a refrigerant circuit 200. In the refrigerant circuit 200, refrigerant circulates through the compressor 122, four-way valve 123, outdoor heat exchanger 124, expansion valve 125, and indoor heat exchanger 1 to implement a vapor compression refrigeration cycle. Air conditioning by the air conditioner 100 is performed by implementing a vapor compression refrigeration cycle. When the four-way valve 123 is switched to the first state (the state shown by the dashed line), the refrigerant that has circulated through the compressor 122, indoor heat exchanger 1, expansion valve 125, and outdoor heat exchanger 124 circulates back to the compressor 122, and heating operation is performed. When the four-way valve 123 is switched to the second state (state shown by the solid line), the refrigerant that has circulated through the compressor 122, the outdoor heat exchanger 124, the expansion valve 125, and the indoor heat exchanger 1 is circulated back to the compressor 122, and cooling operation is performed.

The indoor fan 112 generates an airflow of indoor air that passes through the indoor heat exchanger 1. As the indoor air passes through the indoor heat exchanger 1, heat exchange between the refrigerant passing through the indoor heat exchanger 1 and the indoor air is promoted. The indoor fan 112 can change the volume of air passing through the indoor heat exchanger 1 by changing the rotation speed of the built-in motor.

The outdoor fan 126 generates an airflow of outside air that passes through the outdoor heat exchanger 124. The outdoor fan 126 sends the outside air to the outdoor heat exchanger 124, promoting heat exchange between the refrigerant passing through the outdoor heat exchanger 124 and the outside air. The outdoor fan 126 can change the volume of air passing through the outdoor heat exchanger 124 by changing the rotation speed of the built-in motor.

(1-1) Heating Operation When the indoor unit 110 receives a signal from, for example, the remote controller 150 instructing to perform heating operation, the air conditioner 100 starts heating operation. During heating operation, the air conditioner 100 switches the four-way valve 123 to the first state. The air conditioner 100 adjusts the rotation speed of the compressor 122, the opening of the expansion valve 125, and the rotation speed of the outdoor fan 126 to match the room temperature with the set temperature received from, for example, the remote controller 150. In addition, the air conditioner 100 adjusts the rotation speed of the indoor fan 112 so that the air volume becomes the set air volume received from, for example, the remote controller 150. During heating operation, the outdoor heat exchanger 124 functions as an evaporator of the refrigerant, and the indoor heat exchanger 1 functions as a radiator of the refrigerant.

During heating operation, in the refrigerant circuit 200, the high-temperature, high-pressure refrigerant discharged from the compressor 122 exchanges heat with indoor air sent by the indoor fan 112 in the indoor heat exchanger 1 and dissipates heat. The indoor air heated by the indoor heat exchanger 1 is blown into the room as conditioned air. The refrigerant that dissipates heat in the indoor heat exchanger 1 passes through the expansion valve 125 and is reduced in pressure. The refrigerant that expands due to the reduction in pressure exchanges heat with outside air sent by the outdoor fan 126 in the outdoor heat exchanger 124 and evaporates. In the refrigerant circuit 200, the refrigerant that has passed through the outdoor heat exchanger 124 is drawn into the compressor 122 and compressed.

(1-2) Cooling Operation When the indoor unit 110 receives a signal from the remote controller 150 instructing it to perform the cooling operation, it starts the cooling operation. During the cooling operation, the air conditioner 100 switches the four-way valve 123 to the second state. For example, the air conditioner 100 adjusts the rotation speed of the compressor 122, the opening degree of the expansion valve 125, and the rotation speed of the indoor fan 112 to match the room temperature with the set temperature received from the remote controller 150. The air conditioner 100 also adjusts the rotation speed of the indoor fan 112 so that the air volume becomes the set air volume received from the remote controller 150. During the cooling operation, the outdoor heat exchanger 124 functions as a radiator of the refrigerant, and the indoor heat exchanger 1 functions as an evaporator of the refrigerant.

During cooling operation, in the refrigerant circuit 200, the high-temperature, high-pressure refrigerant discharged from the compressor 122 dissipates heat in the outdoor heat exchanger 124 by exchanging heat with outside air sent by the outdoor fan 126. The refrigerant cooled in the outdoor heat exchanger 124 passes through the expansion valve 125 to be reduced in pressure. The refrigerant expanded by the reduction in pressure exchanges heat in the indoor heat exchanger 1 and evaporates through heat exchange with indoor air sent by the indoor fan 112. The indoor air cooled by the indoor heat exchanger 1 is blown into the room as conditioned air. In the refrigerant circuit 200, the refrigerant that has passed through the indoor heat exchanger 1 is drawn into the compressor 122 and compressed.

(2) Detailed configuration (2-1) Indoor heat exchanger 1
In this embodiment, the indoor heat exchanger 1 is composed of three heat exchange sections, namely, a first heat exchange section 11, a second heat exchange section 12, and a third heat exchange section 13. The difference between the first heat exchange section 11, the second heat exchange section 12, and the third heat exchange section 13 is the arrangement position inside the casing 111. In this embodiment, the case where the first heat exchange section 11, the second heat exchange section 12, and the third heat exchange section 13 have the same structure will be described. Therefore, the structure of the first heat exchange section 11 will be described below as an example, and the description of the structures of the second heat exchange section 12 and the third heat exchange section 13 will be omitted. However, even if the structures of the first heat exchange section 11, the second heat exchange section 12, and the third heat exchange section 13 are not the same, the heat exchanger according to the present disclosure can be applied. The arrangement inside the casing 111 of the first heat exchange section 11, the second heat exchange section 12, and the third heat exchange section 13 will be described later. In addition, the first heat exchange section 11, the second heat exchange section 12, and the third heat exchange section 13 are collectively referred to as the heat exchange section 10.

FIG. 5 shows the first heat exchange section 11 as viewed from diagonally above. FIG. 6 shows an enlarged cross section of the first heat exchange section 11 cut along plane B in FIG. 5. FIG. 7 shows the first heat exchange section 11 as viewed along the thickness direction of the flat tubes 20. The width direction (first direction), thickness direction (second direction), and longitudinal direction of the flat tubes 20 used in the following description correspond to the directions indicated by arrows in FIG. 5, FIG. 6, and FIG. 7. The width direction of the flat tubes 20 coincides with the first direction, which is the direction in which the air undergoing heat exchange in the indoor heat exchanger 1 passes. The thickness direction of the flat tubes 20 coincides with the second direction that intersects with the first direction.

The first heat exchange section 11 has a plurality of flat tubes 20, a plurality of fins 30, a first header 41, a second header 42, and a third header 43. The first heat exchange section 11 is a stacked type heat exchanger in which a plurality of flat tubes 20 are stacked at a predetermined interval in the thickness direction of the flat tubes 20 by a plurality of fins 30. In this embodiment, the indoor heat exchanger 1 has an inner heat exchange section 10i and an outer heat exchange section 10o.

The flat tube 20 is a heat transfer tube through which a refrigerant flows. The flat tube 20 has a cross section formed in a flat oval shape. The flat tube 20 is a multi-hole tube having a plurality of refrigerant flow paths 201 formed perpendicular to the cross section. The plurality of refrigerant flow paths 201 are arranged side by side in the width direction of the flat tube 20. The flat tube 20 is formed by extrusion molding using aluminum or an aluminum alloy, for example. The flat tube 20 of this embodiment is arranged along the longitudinal direction of the indoor unit 110. The flat tube 20 has two

side surfaces

211, 212. The two

side surfaces

211, 212 extend in the width direction and longitudinal direction.

The fin 30 is a strip-shaped plate material through which the flat tubes 20 penetrate at regular intervals. The fin 30 has a plurality of through-holes 310, which are peripheral portions of slit-shaped cutouts for inserting the flat tubes 20. When viewed from the thickness direction of the fin 30, the cutouts of the through-holes 310 are formed so as to extend from one edge extending in the longitudinal direction of the fin 30 toward the other edge while intersecting the edge at right angles. The multiple through-holes 310 are formed at regular intervals in the longitudinal direction of the fin 30. The fin 30 is formed, for example, using aluminum or an aluminum alloy.

The flat tube 20 is inserted into the through-hole 310 so that the width direction coincides with the insertion direction into the notch of the through-hole 310. The multiple fins 30 are arranged in the longitudinal direction of the flat tube 20 at a predetermined interval. In other words, the predetermined interval is the fin pitch. The fins 30 and the flat tube 20 are joined by brazing at the through-hole 310. The multiple flat tubes 20 are joined to the fins 30 so that their ends are aligned in the thickness direction of the flat tube 20. In other words, the multiple flat tubes 20 are joined to the fins 30 so that they are aligned in multiple stages. Figures 5 and 7 show the outer edge formed by the multiple fins 30 aligned in the longitudinal direction of the flat tube 20 and a portion of the multiple fins 30.

Both the inner heat exchange section 10i and the outer heat exchange section 10o are formed in approximately the same shape by joining a predetermined number of flat tubes 20 to a predetermined number of fins 30. The inner heat exchange section 10i is disposed closer to the indoor fan 112 than the outer heat exchange section 10o. The inner heat exchange section 10i and the outer heat exchange section 10o are disposed overlapping in the thickness direction of the flat tubes 20. In other words, the first heat exchange section 11 is composed of two rows of the inner heat exchange section 10i and the outer heat exchange section 10o. In contrast, the number of flat tubes 20 in each row is the number of stages of the first heat exchange section 11. The gaps between the adjacent flat tubes 20 and the gaps between the adjacent fins 30 in each of the inner heat exchange section 10i and the outer heat exchange section 10o form a flow path through which the airflow generated by the indoor fan 112 flows. The flow of the airflow flowing through this flow path is indicated by dashed arrows in FIG. 6.

The first header 41, the second header 42, and the third header 43 are cylindrical members that connect the refrigerant flow paths 201 of the flat tubes 20 to each other at the ends of the flat tubes 20.

The first header 41 is provided at one longitudinal end of the flat tubes 20 of the inner heat exchange section 10i so as to connect the refrigerant flow paths 201 of the flat tubes 20 to each other. Specifically, one longitudinal end of the flat tubes 20 of the inner heat exchange section 10i is inserted into the first header 41 through an opening formed in the side of the first header 41 and fixed to the first header 41 using brazing or the like.

The second header 42 is provided so as to communicate the refrigerant flow paths 201 of the flat tubes 20 of the inner heat exchange section 10i with the refrigerant flow paths 201 of the flat tubes 20 of the outer heat exchange section 10o at the other longitudinal ends of the flat tubes 20 of the inner heat exchange section 10i and the other longitudinal ends of the flat tubes 20 of the outer heat exchange section 10o. Specifically, the other longitudinal ends of the flat tubes 20 of the inner heat exchange section 10i and the other longitudinal ends of the flat tubes 20 of the outer heat exchange section 10o are inserted into the second header 42 through openings formed in the side of the second header 42 and fixed to the second header 42 using brazing or the like.

The third header 43 is provided at one longitudinal end of the flat tubes 20 of the outer heat exchange section 10o so as to connect the refrigerant flow paths 201 of the flat tubes 20 to each other. Specifically, one longitudinal end of the flat tubes 20 of the outer heat exchange section 10o is inserted into the third header 43 through an opening formed in the side of the third header 43 and fixed to the third header 43 using brazing or the like. The third header 43 is connected to the connecting pipe 132 via a branch pipe 431.

The refrigerant that flows into the first header 41 through the connecting pipe 131 passes through the multiple refrigerant flow paths 201 formed in the flat tubes 20 of the inner heat exchange section 10i and flows into the second header 42. The refrigerant that flows into the second header 42 passes through the multiple refrigerant flow paths 201 formed in the outer heat exchange section 10o and flows into the connecting pipe 132 through the third header 43. The refrigerant that flows into the first header 41 through the connecting pipe 132 passes through the multiple refrigerant flow paths 201 formed in the flat tubes 20 of the outer heat exchange section 10o and flows into the third header 43. The refrigerant that flows into the third header 43 passes through the multiple refrigerant flow paths 201 formed in the inner heat exchange section 10i and flows into the connecting pipe 131 through the first header 41.

The first heat exchange section 11 is provided so that the thickness direction of the flat tubes 20 is inclined backward with respect to the up-down direction (vertical direction) when the indoor unit 110 is viewed from the side (when viewed horizontally along the wall WL). As a result, the upper end of the first heat exchange section 11 is arranged so that it is closer to the wall WL than the lower end. The second heat exchange section 12 is provided so that the thickness direction of the flat tubes 20 is inclined forward with respect to the up-down direction (vertical direction) when the indoor unit 110 is viewed from the side. As a result, the lower end of the second heat exchange section 12 is arranged so that it is closer to the wall WL than the upper end. The third heat exchange section 13 is provided so that the thickness direction of the flat tubes 20 is inclined forward with respect to the up-down direction (vertical direction) when the indoor unit 110 is viewed from the side. As a result, the lower end of the third heat exchange section 13 is arranged so that it is closer to the wall WL than the upper end.

(2-1-1) Fin 30
FIG. 8 shows a part of one fin 30. Each fin 30 has a plurality of through-holes 310, one communication portion 320, and a plurality of heat transfer portions 330. The communication portion 320 is a portion that continues continuously in the second direction. The dashed line extending in the second direction shown in FIG. 8 is a boundary between the heat transfer portion 330 and the communication portion 320. The through-hole 310 is a peripheral portion around the notch. A collar 311 that rises along the flat tube 20 is formed on the peripheral portion. In this embodiment, the collar 311 corresponds to the through-hole 310. The direction along the flat tube 20 is a direction that intersects with the first direction and the second direction. The heat transfer portion 330 is a portion other than the through-hole 310 and the communication portion 320.

Each fin 30 also has a fin pitch determining portion 340, a bridge-shaped cut-and-raised portion 350, and a convex portion 360. The fin pitch determining portion 340, the cut-and-raised portion 350, and the convex portion 360 are structures formed in the heat transfer portion 330. The fin pitch determining portion 340 contacts the adjacent fin 30 to determine the fin pitch. The fin pitch of the adjacent fins 30 is determined by the height h1 (see FIG. 10) of the fin pitch determining portion 340. The fin pitch determining portion 340 includes two or more raised portions 341 formed by cutting and raising the heat transfer portion 330 of each fin 30 located in a location other than the communication portion 320 in two or more directions. Therefore, a gap 342 is formed between the raised portions 341. In each fin 30, one fin pitch determining portion 340 is provided for N (N is an integer of 2 or more) flat tubes 20. When the number of fin pitch defining portions 340 in each fin 30 is three or more, it is preferable that the three or more fin pitch defining portions 340 of each fin 30 are arranged so that the number of flat tubes 20 between adjacent fin pitch defining portions 340 is the same. For example, if the number of fin pitch defining portions 340 of each fin 30 is four and N=4, the structure of FIG. 10 is arranged first, followed by three structures of FIG. 9, followed by the structure of FIG. 10, followed by three more structures of FIG. 9, followed by the structure of FIG. 10, followed by three more structures of FIG. 9, followed by the structure of FIG. 10.

The collar 311 of the through portion 310 can be divided into a first rising portion 316 and a second rising portion 317. The first rising portion 316 is a portion of the collar 311 that rises along the flat tube 20 that it penetrates and that comes into contact with the adjacent fin 30. In contrast, the second rising portion 317 is a portion that rises along the flat tube 20 that it penetrates and that does not come into contact with the adjacent fin 30. The first rising portion 316 is disposed on only one of the two opposing sides 318, 319 (see FIG. 8) of the notch.

The first standing portion 316 helps maintain the fin pitch defined by the fin pitch defining portion 340. The first standing portion 316 also suppresses buckling of the fin 30 when the flat tube 20 is inserted. To make it easier to suppress buckling, it is preferable that the first standing portion 316 is provided at the entrance of the notch of the penetration portion 310. It is also preferable that the length L2 of the first standing portion 316 is 50% or less of the length L1 of the fin 30 in the first direction. It is preferable that the surface where the first standing portion 316 contacts the adjacent fin 30 is rectangular in order to stably support the fin 30.

(2-1-2) Specific configuration of fin pitch defining portion 340 FIG. 8 shows a part of the fin 30 when N is 4. FIG. 9 shows a portion of the fin 30 where the fin pitch defining portion 340 is not formed between adjacent flat tubes 20. FIG. 10 shows a portion of the fin 30 where the fin pitch defining portion 340 is formed between adjacent flat tubes 20. When N=4, one fin pitch defining portion 340 is provided for four flat tubes 20. In other words, when N=4, four flat tubes 20 are arranged between two adjacent fin pitch defining portions 340 in each fin 30.

In the heat transfer section 330 of the fin 30 shown in FIG. 9, in which the fin pitch determining section 340 is not formed, three bridge-shaped cut-outs 350 are formed. In contrast, in the heat transfer section 330 shown in FIG. 10, in which the fin pitch determining section 340 is formed, only one bridge-shaped cut-out 350 is formed. In the bridge-shaped cut-out 350, airflow that passes through the flat, uncut portion of the heat transfer section 330 passes along both sides of the cut-out 350. Such a bridge-shaped cut-out 350 is sometimes called a slit. The heat transfer section 330 in which three bridge-shaped cut-outs 350 are formed can exchange heat more efficiently than the heat transfer section 330 in which one bridge-shaped cut-out 350 is formed.

There are four gaps 342 between the four rising parts 341 of the fin pitch determination part 340. Two of the four gaps 342 are arranged so as to line up in the first direction, and the remaining two are arranged so as to line up in the second direction. The rising parts 341 are formed by forming a cross cutting line in the flat heat transfer part 330 and cutting and raising it so that the folding lines form a circle. This allows the air flowing in the first direction to easily pass through the two gaps 342. Also, condensed water easily flows in the second direction through the other two gaps 342.

(2-1-3) Fin pitch defining portion and heat transfer coefficient A graph showing the relationship between the fin pitch defining portion 340 and heat transfer is shown in FIG. 11. The graph shown in FIG. 11 shows the air-side heat transfer coefficient (W/m 2 ) of the configuration X1 using the fin 30 shown in FIG. 12, the configuration Y1 using the fin 530 shown in FIG. 13, the configuration Y2 using the fin 630 shown in FIG. 14, and the configuration Y3 using the fin ⁷³⁰ shown in FIG. 14. These graphs are for comparing the difference in the amount of heat transferred from the

fins

30, 530, 630, and 730 to the air when the temperature of the

fins

30, 530, 630, and 730 with the same area and the temperature of the air are the same. The higher the air-side heat transfer coefficient of the fins used, the higher the heat exchange efficiency of the heat exchanger. The graph shows the results of measurements of three rows of fins under conditions of a row pitch of 10 mm and a row pitch of 9.7 mm. The direction of the air flow is indicated by the arrow AF.

The "N" on the horizontal axis of the graph corresponds to the number of flat tubes 20 for one fin

pitch determining portion

340, 540 in each fin of the configurations X1, Y1. When N=1, the fin

pitch determining portion

340, 540 is formed in all heat transfer portions 330. In other words, when N=1, the structure shown in FIG. 9 does not appear in each

fin

30, 530. When N=2, two flat tubes 20 are arranged between adjacent fin

pitch determining portions

340, 540. In other words, when N=2, for example, in each fin 30, the structure shown in FIG. 9 and the structure shown in FIG. 10 appear alternately. When N=3, three flat tubes 20 are arranged between adjacent fin

pitch determining portions

340, 540. In other words, when N=3, for example, in each fin 30, the structure shown in FIG. 9 appears twice in succession, and then the structure shown in FIG. 10 appears once.

12 shows a configuration using the fin 30 according to the above embodiment, in which the heat transfer section 330 is provided with the fin pitch determining section 340, one bridge-type cut-and-raised section 350, and a convex section 360, and the through section 310 is provided with the first upright section 316. The difference between the configuration X1 shown in FIG. 12 and the configuration Y1 shown in FIG. 13 is the difference in the structure of the fin

pitch determining sections

340 and 540. The fin pitch determining section 340 has a gap 342, but the fin pitch determining section 540 does not have a structure corresponding to the gap 342. The fin pitch determining section 340 in FIG. 12 has four upright sections 341, but the fin pitch determining section 540 in FIG. 13 has only one circular upright section. In the configuration Y2 shown in FIG. 14, two spacers 640 disclosed in Patent Document 1 are provided in the heat transfer section 330. Therefore, only one bridge-type cut-and-raised section 350 is provided in the heat transfer section 330. Therefore, the configuration Y2 shown in FIG. 14 has a low air-side heat transfer coefficient, as shown by the dashed line in FIG. 11. The configuration Y3 shown in FIG. 15 has a fin pitch determining portion 740 provided at the through-hole 710. The configuration Y3, in which the fin pitch determining portion 740 is provided only at the through-hole 710, is difficult to manufacture and is not practical, but it is possible to provide three bridge-type cut-and-raised portions 350 on each of the heat transfer portions 330. Therefore, the configuration Y3 shown in FIG. 15 has a good air-side heat transfer coefficient, as shown by the dashed line in FIG. 11.

The air-side heat transfer coefficients of configurations X1 and Y1 shown in Figures 12 and 13 for N=1 are both inferior to the air-side heat transfer coefficient of configuration Y2. However, the air-side heat transfer coefficients of configurations X1 and Y1 shown in Figures 12 and 13 for N=2 or more are better than the air-side heat transfer coefficient of configuration Y2. Furthermore, as N becomes larger, such as N=4 and N=6, the air-side heat transfer coefficient approaches that of configuration Y3 shown in Figure 15. Also, when comparing configurations X1 shown in Figure 12 and Y1 shown in Figure 13, the air-side heat transfer coefficient of configuration X1 is higher than that of configuration Y1, regardless of the value of N.

(3) Modifications (3-1) Modification A
In the above embodiment, the case where the indoor unit 110 is a wall-mounted type has been described. However, the indoor unit to which the indoor heat exchanger 1 described in the above embodiment can be applied is not limited to the wall-mounted type. The indoor heat exchanger 1 according to the present disclosure can be applied to, for example, a duct-type indoor unit as shown in FIG. 16, which is embedded in a ceiling and distributes conditioned air through a duct. In FIG. 16, an airflow is generated in the indoor heat exchanger 1 by the indoor fan 112. For example, a centrifugal fan can be used for the indoor fan 112 in FIG. 16. For example, a sirocco fan can be used for the centrifugal fan. The shape of the indoor heat exchanger 1 shown in FIG. 16 is an I-shape when viewed from the side, but the shape when viewed from the side may be bent into a wedge shape as shown in FIG. 17. In this case, for example, a cross-flow fan may be used for the indoor fan 112 as shown in FIG. 17, or a centrifugal fan may be used instead of the cross-flow fan. In FIG. 17, the arrow AF of the two-dot chain line indicates the direction in which the air flows. As shown in Fig. 18, the heat exchanger 1 can also be arranged in an N-shape when viewed from the side. In the indoor unit 110 in Fig. 18, as shown by the arrow AF, the indoor fan 112 is configured to make air flow from bottom to top in the direction of gravity. The indoor unit 110 in Fig. 18 can also be configured to make air flow from top to bottom.

(3-2) Modification B
In the above embodiment, the case where the fin pitch defining portion 340 has four rising portions 341 has been described. However, the number of rising portions 341 of one fin pitch defining portion 340 may be three, as shown in Fig. 19. In this case, as shown in Fig. 19, the gaps 342 between adjacent rising portions 341 are arranged to be offset in the air flow direction (first direction), which makes it easier to reduce the resistance of the air flow. In addition, the gaps 342 between adjacent rising portions 341 are arranged side by side in the direction in which condensation water flows (second direction), which makes it easier for condensation water to flow.

Furthermore, the number of rising portions 341 of the fin pitch determining portion 340 can be two. When the number of rising portions 341 is two, arranging two gaps 342 side by side in the air flow direction (first direction) can facilitate the flow of air. When the number of rising portions 341 is two, arranging two gaps 342 side by side in the direction in which condensation water flows (second direction) can facilitate the flow of condensation water. Note that the size of the two or more rising portions 341 may be the same as in the above embodiment, but they do not have to be the same size as shown in FIG. 19.

(3-3) Modification C
In the above embodiment, a case has been described in which the fin pitch specifying portion 340 and the first standing portion 316 are combined. However, the fin pitch specifying portion 340 and the first standing portion 316 do not have to be combined. For example, a configuration may be made in which the fin pitch specifying portion 340 is provided and the first standing portion 316 is not provided. Furthermore, the first standing portion 316 may be combined with a fin pitch specifying portion other than the fin pitch specifying portion 340.

(3-4) Modification D
In the above embodiment, the collar 311 is provided on the through-hole 310. However, the collar 311 may not be provided, and only the first upright portion 316 may be configured to stand up at the through-hole 310.

(3-5) Modification E
In the above embodiment, a case has been described in which the bridge-shaped cut-and-raised portions 350 are formed in the heat transfer portion 330. However, the structure for promoting heat exchange is not limited to the bridge-shaped cut-and-raised portions 350 (slits). For example, the structure for promoting heat exchange may be a louver-shaped cut-and-raised portion that is cut and raised obliquely with respect to the plane of the heat transfer portion 330.

(4) Features (4-1)
In the above embodiment or modified example, each fin 30 has a plurality of through-holes 310, a communication portion 320, and one or more fin pitch defining portions 340. A plurality of flat tubes 20 penetrate the plurality of through-holes 310. The communication portion 320 extends in a second direction intersecting with the first direction without penetrating the plurality of flat tubes 20. The one or more fin pitch defining portions 340 contact adjacent fins 30 to define the fin pitch. In each fin 30, one fin pitch defining portion 340 is provided for N (N is an integer of 2 or more) flat tubes 20. The fin pitch defining portion 340 of each fin 30 includes two or more rising portions 341 formed by cutting and raising the heat transfer portion 330 of each fin 30 located in a place other than the communication portion 320 in two or more directions. Since the two or more rising portions 341 of the fin pitch defining portion 340 are cut and raised in two or more directions, gaps 342 are formed between the two or more rising portions 341, and it is possible to prevent at least one of the ventilation path and the drainage path from being narrowed by the fin pitch defining portion 340. As a result, it is possible to prevent a decrease in heat exchange efficiency or drainage performance due to the fin pitch defining portion 340.

(4-2)
19 described in Modification B, the fin pitch specifying portion 340 can support adjacent fins 30 at three points with the three rising portions 341. As a result, the fin pitch specifying portion 340 can firmly support the adjacent fins 30 and stably specify the fin pitch. In addition, the fin pitch specifying portion 340 including the three rising portions 341 has three gaps 342, and therefore the arrangement of the gaps 342 can prevent at least one of the ventilation path and the drainage path from being narrowed by the fin pitch specifying portion 340.

(4-3)
The fin pitch defining portion 340 of the above embodiment includes four rising portions 341 cut and raised in four directions. Since the four rising portions 341 of the fin pitch defining portion 340 are cut and raised in four directions, two gaps 342 can be arranged side by side in the first direction, and the other two gaps 342 can be arranged side by side in the second direction. The two gaps 342 arranged side by side in the first direction can prevent the ventilation path from narrowing. In addition, the two gaps 342 arranged side by side in the second direction can prevent the drainage path from narrowing. As a result, the arrangement of the gaps 342 can prevent the ventilation path and the drainage path from narrowing due to the fin pitch defining portion 340.

(4-4)
As shown in the graph of configuration X1 in Fig. 11, the fin pitch defining portion 340 can be provided for every four flat tubes or every six flat tubes, and the decrease in the heat transfer coefficient can be suppressed by reducing the proportion of the portion in each fin 30 where the fin pitch defining portion 340 is provided. Reducing the proportion of the portion where the fin pitch defining portion 340 is provided means increasing N, in other words, reducing the value of (the number of configurations in Fig. 10 / the number of configurations in Fig. 9) in each fin 30.

(4-5)
In the above embodiment, when the number of fin pitch defining portions 340 in each fin 30 is three or more, it is preferable that the three or more fin pitch defining portions 340 of each fin 30 are arranged so that the number of flat tubes 20 between adjacent fin pitch defining portions 340 is the same. When arranged in this manner, the fin pitch defining portions 340 are arranged so that the locations where the heat transfer coefficient decreases are arranged regularly, and the decrease in the overall heat transfer coefficient can be suppressed compared to when the fin pitch defining portions 340 are arranged irregularly.

(4-6)
Each penetration portion 310 of each fin 30 in the above embodiment has a first rising portion 316 that rises along the corresponding flat tube 20 and contacts the adjacent fin 30, and a second rising portion 317 that rises along the corresponding flat tube 20 and does not contact the adjacent fin 30. Since the first rising portion 316 of the penetration portion 310 contacts the adjacent fin 30, it is possible to suppress buckling when the penetration portion 310 is inserted into the flat tube 20. In addition, the first rising portion 316 can help ensure the fin pitch.

(4-7)
Each penetration portion 310 of each fin in the above embodiment has a first rising portion 316 that rises along the corresponding flat tube 20 and contacts the adjacent fin 30. When there is another portion that defines the fin pitch other than the first rising portion 316, the first rising portion 316 can suppress buckling and fin crushing when the flat tube 20 is inserted, and can help ensure the fin pitch by the other portion that defines the fin pitch. In the above embodiment, the other portion that defines the fin pitch is the fin pitch defining portion 340, but the other portion that defines the fin pitch is not limited to the fin pitch defining portion 340.

(4-8)
The first standing portion 316 in the above embodiment is provided on only one of the two side surfaces 211, 212 (see FIG. 6 ) of each flat tube 20 in the longitudinal direction of each fin 30. In other words, it is arranged on only one of the two opposing sides 318, 319 (see FIG. 8 ) of the cutout of the through-hole 310. Since the first standing portion 316 is provided on only one of the two side surfaces of the flat tube 20, the height of the first standing portion 316 can be increased to a height close to the thickness of the flat tube 20 compared to when the first standing portion 316 is provided on both sides.

Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the present disclosure as set forth in the claims.

1. Indoor heat exchanger (Example of a heat exchanger)
20 Flat tube 30 Fin 310 Penetration portion 316 First rising portion 317 Second rising portion 320 Communication portion 330 Heat transfer portion 340 Fin pitch regulation portion 341 Rising portion

JP 2012-163318 A

Claims

A heat exchanger (1) comprising a plurality of fins (30) and a plurality of flat tubes (20), and performing heat exchange of air passing between the plurality of flat tubes and the plurality of fins in a first direction,
Each of the fins is
A plurality of penetration portions (310) through which the plurality of flat tubes penetrate;
A communication portion (320) extending in a second direction intersecting the first direction without penetrating the plurality of flat tubes;
one or more fin pitch defining portions (340) that contact adjacent fins to define a fin pitch;
having
The fin pitch defining portion is provided for each of N flat tubes (N is an integer of 2 or more) in each of the fins,
The fin pitch defining portion of each of the fins includes two or more raised portions (341) formed by cutting and raising the heat transfer portion (330) of each of the fins located in a position other than the communicating portion in two or more directions.
The fin pitch defining portion includes three raised portions formed by cutting and raising the heat transfer portion of each of the fins located in a position other than the communication portion in three directions.
A heat exchanger (1) according to claim 1.
The fin pitch defining portion includes four raised portions formed by cutting and raising the heat transfer portion of each of the fins located in a position other than the communication portion in four directions.
A heat exchanger (1) according to claim 1.
The number of flat tubes is four or more,
The fin pitch defining portion is provided for every four flat tubes.
A heat exchanger (1) according to any one of claims 1 to 3.
The number of flat tubes is six or more,
The fin pitch defining portion is provided for every six flat tubes.
A heat exchanger (1) according to any one of claims 1 to 3.
the number of the fin pitch defining portions in each of the fins is three or more,
The three or more fin pitch defining portions of each fin are arranged so that the number of flat tubes between adjacent fin pitch defining portions is the same.
A heat exchanger (1) according to any one of the preceding claims.
Each of the penetration portions of each of the fins has a first rising portion (316) that rises along the corresponding flat tube and contacts the adjacent fin, and a second rising portion (317) that rises along the corresponding flat tube and does not contact the adjacent fin.
A heat exchanger (1) according to any one of the preceding claims.
The air passing in the first direction is indoor air that is heat exchanged in an indoor unit that conditions the air in the room.
A heat exchanger (1) according to any one of the preceding claims.
A heat exchanger (1) comprising a plurality of flat tubes (20) and a plurality of fins (30),
Each of the fins has a plurality of through-portions (310) through which the plurality of flat tubes pass,
Each of the penetrations has a first upstanding portion (316) that rises along the corresponding flat tube and contacts an adjacent fin.
The first upright portion is provided on only one of two side surfaces of each of the flat tubes in the longitudinal direction of each of the fins.
A heat exchanger (1) according to claim 9.
Each of the through portions has a second upright portion (317) that rises along the corresponding flat tube and does not contact the adjacent fin as a portion other than the first upright portion,
The first standing portion stands higher than the second standing portion.
A heat exchanger (1) according to claim 9 or claim 10.