JP2021116981A - Heat exchanger - Google Patents

Abstract

To achieve improvement of heat radiation performance.SOLUTION: A heat exchanger 10 includes: flat heat transfer pipes 12 each of which has passages 12A and which are arranged at intervals so that flat outer surfaces 12S face each other; and corrugated fins 13 which are disposed between the adjacent heat transfer pipes 12 and extend meandering. Each corrugated fin 13 has: main heat transfer parts 20 which are arranged so as to traverse an area between the adjacent heat transfer pipes 12; a folded part 21 connected to the adjacent main heat transfer parts 20. The folded part 21 is provided with: pipe contact parts 25 which are placed in contact with the flat outer surface 12S in the heat transfer pipe 12; and sub heat transfer parts 26 each of which is connected to an end part, which is opposite to the main heat transfer part 20 side, in the pipe contact part 25 and extends so as to be spaced away from the heat transfer pipe 12.SELECTED DRAWING: Figure 3

Description

The techniques disclosed herein relate to heat exchangers.

As conventional heat exchangers, those described in Patent Documents 1 and 2 below are known. In the heat exchanger described in Patent Document 1, the bent portions of the corrugated fins are arranged so as to face each other in the vertical direction, and the upper bent portion is cut open to form a section portion, and the formed section portion and the lower side are formed. Bring the bent part into contact. As a result, the condensed water generated in the heat exchanger is drained through the section portion and the bent portion. Further, by forming a drainage portion at a position where the bent portion of the corrugated fin and the side surface of the flat heat transfer tube are in contact with each other, the condensed water collected in the upper part of the bent portion is drained through the draining portion.

On the other hand, in the heat exchanger described in Patent Document 2, the width of each corrugated fin sandwiched between the tubes is provided longer than the width of the tube, and is provided so as to extend to the upstream side and the downstream side of the tube. Further, the bent portion on the lower side of the corrugated fin is provided with a fitting portion for inserting the tube and having the same depth as the thickness of the tube. Further, the fin pitch of the corrugated fin is provided to be small. As a result, the lower bent portion of the corrugated fin and the upper bent portion of the lower corrugated fin come into close contact with each other. Then, the water transmitted to the lower bent portion of the corrugated fin is transmitted to the upper bent portion of the lower corrugated fin, and the water adhering to the heat exchanger is continuously transmitted through each corrugated fin and drained.

Japanese Unexamined Patent Publication No. 2014-47975

Japanese Unexamined Patent Publication No. 7-55380

In the corrugated fin described in Patent Document 1 described above, in order to arrange the flat heat transfer tube on the upper part of the corrugated fin, a recess is formed by cutting out by substantially the same thickness as the flat heat transfer tube. .. However, in Patent Document 1, since the contact area between the corrugated fin and the flat heat transfer tube is reduced by the amount of the recess, the heat transfer efficiency is lowered, and as a result, the heat exchange performance is lowered.

In Patent Document 2 described above, a technique of forming a fitting portion by denting the central portion of the lower bent portion of the corrugated fin and a fitting portion by forming a notch in the lower bent portion are described. The technique of forming is described. Regarding the latter of these, as in Patent Document 1, since the contact area between the corrugated fin and the tube is reduced by the amount of the notch, there is a problem that the heat transfer efficiency and the heat exchange performance are lowered. On the other hand, regarding the former, although the contact area between the corrugated fin and the tube is sufficiently secured, there is still room for improvement in the heat exchange performance.

The technique described in the present specification has been completed based on the above circumstances, and an object thereof is to improve heat exchange performance.

(1) The heat exchanger according to the technique described in the present specification is a flat heat transfer tube having a plurality of flow paths inside, and a plurality of heat transfer tubes arranged at intervals so that the flat outer surfaces face each other. And a corrugated fin that is arranged between the adjacent heat transfer tubes and extends while meandering, and the corrugated fin is arranged so as to cross between the adjacent heat transfer tubes. It has a portion and a folded portion connected to the adjacent main heat transfer portion, and the folded portion includes a pipe contact portion that is in contact with the flat outer surface of the heat transfer tube and the pipe contact portion. A sub heat transfer portion that is connected to the end portion of the contact portion on the side opposite to the main heat transfer portion side and extends away from the heat transfer tube is provided.

(2) Further, in addition to the above (1), in the heat exchanger, the pipe contact portions are arranged in pairs so as to be connected to the adjacent main heat transfer portions, respectively, and the sub heat transfer portions. May be arranged in pairs so as to be connected to the paired pipe contact portions.

(3) Further, in addition to the above (2), the heat exchanger may be arranged so that the paired sub-heat transfer portions face each other so that a gap is interposed between them.

(4) Further, in the heat exchanger, in addition to the above (2) or the above (3), the extension ends of the paired sub-heat transfer portions may be connected to each other.

(5) Further, in addition to the above (2) or (3), the heat exchanger may be cantilevered so that the paired sub-heat transfer portions have free ends. good.

(6) Further, in addition to any of the above (1) to (5), the heat exchanger extends in the main heat transfer section along the arrangement direction of the heat transfer tube and the corrugated fin. A louver is provided, and the sub-heat transfer portion may be arranged so that the extending end thereof overlaps with respect to the end portion of the louver in the alignment direction in the alignment direction.

(7) Further, in addition to the above (1) to (6), the heat exchanger has a width in which a plurality of the flow paths are lined up with respect to the heat transfer tube. It has a protruding portion that protrudes outward in the direction, and the protruding portion has a side in which the heat transfer tube and the corrugated fins are arranged in a direction from the tube contact portion toward the extending end of the sub heat transfer portion. A pipe overlapping portion that extends toward the opposite side and is arranged so as to have a positional relationship of overlapping with the heat transfer tube in the alignment direction may be provided.

(8) Further, in the heat exchanger, in addition to the above (7), the folded portion and the pipe overlapping portion may have the same length.

(9) Further, in addition to any of the above (1) to (8), the heat exchanger is provided with a heat transfer tube side positioning portion on the surface of the heat transfer tube facing the corrugated fin. On the other hand, on the surface of the corrugated fin facing the heat transfer tube, a fin-side positioning portion that is unevenly fitted to the heat transfer tube-side positioning portion may be provided.

(10) Further, in the heat exchanger, in addition to the above (9), the heat transfer tube side positioning portion may have a concave shape, whereas the fin side positioning portion may have a convex shape.

(11) Further, in the heat exchanger, in addition to the above (9), the heat transfer tube side positioning portion may have a convex shape, whereas the fin side positioning portion may have a concave shape.

According to the technique described in the specification of the present application, the heat dissipation performance can be improved.

A side view showing a schematic configuration of the heat exchanger according to the first embodiment. Cross-sectional view of the heat transfer tube and corrugated fins that make up the heat exchanger Side view of heat transfer tube and corrugated fin Enlarged cross-sectional view of the area around the folded part of the corrugated fin Side view of the heat transfer tube and corrugated fins constituting the heat exchanger according to the second embodiment. Enlarged side view of the area around the folded part of the corrugated fin Cross-sectional view of a heat transfer tube and corrugated fins constituting the heat exchanger according to the third embodiment. Side view showing the state before assembling the heat transfer tube and the corrugated fin Cross-sectional view taken along the line AA of FIG. 7 in the heat transfer tube and the corrugated fin. Cross-sectional view of a heat transfer tube and corrugated fins constituting the heat exchanger according to the fourth embodiment. Front view showing the state before assembling the heat transfer tube and corrugated fin Cross-sectional view taken along the line AA of FIG. 10 in the heat transfer tube and the corrugated fin. Side view of the heat transfer tube and corrugated fins constituting the heat exchanger according to the fifth embodiment. Side view of the heat transfer tube and corrugated fins constituting the heat exchanger according to the sixth embodiment. Cross-sectional view of a heat transfer tube and corrugated fins constituting the heat exchanger according to the seventh embodiment.

<Embodiment 1>
The first embodiment will be described with reference to FIGS. 1 to 5. In this embodiment, a parallel flow type heat exchanger 10 is shown as an example of the fin tube type heat exchanger. The X-axis, Y-axis, and Z-axis are shown in each drawing, and each axis direction is drawn so as to be the direction shown in each drawing. Of these, the Z-axis direction substantially coincides with the vertical direction, and the X-axis direction and the Y-axis direction substantially coincide with the horizontal direction. Unless otherwise specified, the vertical direction is used as the reference for the upper and lower descriptions.

FIG. 1 is a side view showing a schematic configuration of the heat exchanger 10. As shown in FIG. 1, the heat exchanger 10 is arranged so as to be alternately and repeatedly arranged with a pair of header tubes 11, a plurality of heat transfer tubes (tubes) 12 connected to the pair of header tubes 11, and heat transfer tubes 12. A plurality of corrugated fins 13 and a pair of side seats 14 arranged so as to sandwich the corrugated fins 13 group from above and below are provided. Aluminum having a small specific gravity and excellent thermal conductivity is used as a main material for the header tube 11, the heat transfer tube 12, the corrugated fin 13, and the side sheet 14 constituting the heat exchanger 10. Further, the heat transfer tube 12 and the corrugated fin 13 are arranged in the same direction as the Z-axis direction. Note that FIG. 1 shows only a schematic configuration of the heat exchanger 10, and the specific number of laminated heat transfer tubes 12 and corrugated fins 13 can be appropriately changed other than shown in the drawing.

The header tube 11 is made of a single-sided clad material in which a brazing material is clad on one surface of the core material. The pair of header tubes 11 each have a cylindrical shape, and are arranged so that their axes are parallel to each other and coincide with the Z-axis direction. An inlet pipe 15 and an outlet pipe 16 through which the refrigerant enters and exits are connected to the header pipe 11 of one of the pair of header pipes 11 (on the right side in FIG. 1). Inside each header pipe 11, a partition plate 11A for dividing (dividing) the flow path of the refrigerant is provided. The partition plate 11A allows the refrigerant to move back and forth between the pair of header pipes 11 a plurality of times via the heat transfer pipe 12.

FIG. 2 is a cross-sectional view of a part of the heat transfer tube 12 and the corrugated fin 13 constituting the heat exchanger 10. As shown in FIG. 2, the heat transfer tube 12 has a porous structure in which a plurality of flow paths 12A are arranged side by side in a row, and has a horizontally long flat shape along the arrangement direction of the plurality of flow paths 12A. .. The heat transfer tube 12 is manufactured by extrusion processing, and its extrusion direction coincides with the length direction of the heat transfer tube 12 (the axial direction of the flow path 12A). A protrusion 12A1 is provided on the peripheral surface of each flow path 12A in the heat transfer tube 12. The protrusion 12A1 can positively cause a turbulent flow in the refrigerant flowing in the flow path 12A, thereby improving the heat transfer efficiency. The heat transfer tube 12 is arranged so that the length direction coincides with the X-axis direction, the width direction (arrangement direction of the flow paths 12A) coincides with the Y-axis direction, and the thickness direction (height direction) coincides with the Z-axis direction. ing. The thickness of the heat transfer tube 12 is, for example, about 1.93 mm, but it can be changed as appropriate in addition to this value. The heat transfer tube 12 is brazed in a state where both ends in the length direction are inserted into openings formed in the peripheral surfaces of the pair of header tubes 11, whereby each flow path 12A is inside the header tube 11. It is connected in a state of communicating with the space. A plurality of heat transfer tubes 12 are arranged side by side at regular intervals in the Z-axis direction (details are about the height dimension of the corrugated fin 13 described later) so that the flat outer surfaces 12B face each other. The number of arrangements is one less than the number of arrangements of the corrugated fins 13 described later. The flat outer surface 12S of the heat transfer tube 12 is a surface along the horizontal direction (X-axis direction and Y-axis direction). Further, the surface of the heat transfer tube 12 is preferably coated with zinc in order to prevent corrosion, but this is not always the case.

The side seat 14 will be described prior to the corrugated fin 13. As shown in FIG. 1, the side sheet 14 has the same configuration as the heat transfer tube 12 except that it does not have the flow path 12A. That is, the side sheet 14 has a horizontally long and flat plate shape, and is arranged so that the length direction coincides with the X-axis direction, the width direction coincides with the Y-axis direction, and the thickness direction coincides with the Z-axis direction. ing. The side seats 14 are arranged in pairs at positions spaced apart from the upper side and the lower side in the Z-axis direction with respect to the heat transfer tubes 12 located at the uppermost stage and the lowermost stage. The flat outer surface 14S of each side sheet 14 is arranged so that the flat outer surface 14S faces the flat outer surface 12S of each heat transfer tube 12 located at the uppermost stage and the lowermost stage. The side seats 14 are located at the upper and lower ends of the heat exchanger 10 in the vertical direction, and function as protective plates for the corrugated fins 13 described below. The side sheets 14 are arranged so as to be close to or in contact with the peripheral surfaces of the pair of header tubes 11, but are inserted into the openings formed in the peripheral surfaces of the pair of header tubes 11 as in the heat transfer tube 12. It does not matter if it is brazed in a state of being brazed. Further, the distance between the side sheet 14 and the adjacent heat transfer tubes 12 is made equal to the distance between the adjacent heat transfer tubes 12.

First, a schematic configuration of the corrugated fin 13 will be described with reference to FIGS. 1 and 3. The corrugated fin 13 is made of a double-sided clad material in which a brazing material is clad on both surfaces of the core material, and is formed by bending an elongated strip-shaped base material along the X-axis direction. .. As shown in FIG. 3, the corrugated fin 13 has a meandering shape bent in a corrugated shape, and extends along the length direction (X-axis direction) of the heat transfer tube 12. A plurality of corrugated fins 13 are lined up at intervals of about the thickness of the heat transfer tube 12 in the Z-axis direction, and are vertically adjacent to each heat transfer tube 12 and each side sheet 14 in the Z-axis direction. Multiple are arranged. The corrugated fin 13 has a meandering shape as described above, so that the spaces vertically adjacent to the heat transfer tube 12 are divided into a plurality of ventilation passages 50. The ventilation passage 50 is open to both sides in the Y-axis direction, and is blown by a blower from one side thereof. The plurality of corrugated fins 13 are arranged so as to be interposed between adjacent heat transfer tubes 12 in the Z-axis direction and between the heat transfer tubes 12 and the side sheet 14 in the Z-axis direction. The former is located at a stage other than the top and bottom stages, and the latter is located at the top and bottom stages. These corrugated fins 13 are brazed in a state of being in contact with the flat outer surfaces 12S and 14S of the heat transfer tube 12 and the side sheet 14. As a result, each corrugated fin 13 located between the adjacent heat transfer tubes 12 and located at other than the uppermost stage and the lowermost stage exchanges heat with each heat transfer tube 12 located above and below itself. Can be done. Further, the two corrugated fins 13 located between the heat transfer tube 12 and the side sheet 14 at the uppermost stage and the lowermost stage are between the heat transfer tube 12 located on the upper side or the lower side with respect to the heat transfer tube 12. The heat can be exchanged, and each side sheet 14 located on the lower side or the upper side with respect to itself covers the side sheet 14 from the outside in the Z-axis direction for protection. Each corrugated fin 13 is supposed to exchange heat with the air existing in the ventilation passage 50.

The detailed configuration of the corrugated fin 13 will be described again with reference to FIGS. 2 to 4 as appropriate. FIG. 3 is a side view of a part of the heat transfer tubes 12 and the corrugated fins 13 constituting the heat exchanger 10. It should be noted that FIGS. 2 to 4 show detailed configurations of the heat transfer tube 12 and the corrugated fin 13, and the expressions are different from those of FIG. 1, which shows the schematic configuration. As shown in FIGS. 2 and 3, the corrugated fins 13 have a plurality of main heat transfer portions 20 arranged so as to cross between adjacent heat transfer tubes 12, and a plurality of folded portions connected to the adjacent main heat transfer portions 20. 21 and. The plurality of main heat transfer portions 20 are all inclined with respect to the Z-axis direction and the X-axis direction, and adjacent ones are inclined in opposite directions to each other. Therefore, the adjacent main heat transfer portions 20 have different intervals between one end and the other end in the Z-axis direction, and the ends on the narrow side are connected to the folded-back portion 21. There is. The ventilation passage 50 partitioned by the main heat transfer portion 20 and the folded portion 21 having such a configuration has a substantially triangular shape when viewed from the Y-axis direction. In the present embodiment, in the ventilation passage 50, the left side of FIG. 2 is the upstream side (leeward side) of the air flow, and the right side of FIG. 2 is the downstream side (leeward side) of the air flow. A blower for generating an air flow may be provided on at least one of the upstream side and the downstream side of the air flow with respect to the ventilation passage 50. The main heat transfer portions 20 provided in the corrugated fins 13 located at the uppermost and lowermost stages shown in FIG. 1 are arranged so as to cross between the heat transfer tube 12 and the side seat 14. Since the corrugated fins 13 meander vertically and extend, the plurality of folded portions 21 are located above the plurality of main heat transfer portions 20 arranged along the X-axis direction in the Z-axis direction. And those located on the lower side in the Z-axis direction are included.

As shown in FIGS. 2 and 3, the main heat transfer unit 20 is provided with a louver (cut-up piece) 22 extending along the Z-axis direction (arrangement direction of the heat transfer tube 12 and the corrugated fin 13). There is. The louver 22 has both side edges along its extending direction (Z-axis direction) separated from the main heat transfer portion 20, whereas both ends in the extending direction are connected to the main heat transfer portion 20. It is cut up in a double-sided shape. The louver 22 is cut and raised so as to be inclined in the horizontal direction with respect to the plate surface of the main heat transfer portion 20. A slit exists between the side edge portion of the louver 22 and the main heat transfer portion 20, and the adjacent ventilation passages 50 are communicated with each other through the slit, and air can flow in and out. The louver 22 having such a configuration improves the heat transfer efficiency to the air existing in the ventilation passage 50, and improves the heat exchange performance. A plurality of louvers 22 are arranged side by side at intervals in the Y-axis direction, which is the width direction of the louvers, and are aligned so that the continuous positions with respect to the main heat transfer portions 20 are substantially the same in the Z-axis direction. There is. Since the extending direction of these louvers 22 coincides with the vertical direction, the heat exchanger 10 is used as an evaporator, and even if condensed water is generated on the surface of the louver 22 due to the heat exchange, the condensed water is condensed. Water easily falls down the louver 22. As a result, the louver 22 is less likely to retain condensed water, so that the heat transfer efficiency between the air and the corrugated fin 13 in the ventilation passage 50 is improved, and the heat exchange performance is improved.

As shown in FIGS. 2 and 3, the main heat transfer section 20 includes a projecting portion 23 projecting to the outside of the heat transfer tube 12 in the Y-axis direction (width direction of the heat transfer tube 12), and a heat transfer tube 12 connected to the projecting portion 23. A pipe overlapping portion 24, which has a positional relationship of overlapping with respect to the Z-axis direction, is provided. It is preferable that the protruding portion 23 is selectively arranged so as to be connected to the right side of FIG. 2 in the Y-axis direction of the main heat transfer portion 20, that is, the downstream end portion of the air flow in the ventilation passage 50. In this way, even if the heat exchanger 10 is used as an evaporator and condensed water is generated on the surface of the main heat transfer unit 20 due to the heat exchange, the condensed water is projected by using the air flow. It can be made to flow toward the portion 23. Since the protruding portion 23 is inclined with respect to the Z-axis direction and the X-axis direction so as to be parallel to the main heat transfer portion 20, it can be said that the protruding portion 23 is an extension portion of the main heat transfer portion 20. Therefore, the surface area of the main heat transfer portion 20 is increased by the amount that the protruding portion 23 is extended, and further, the surface area of the main heat transfer portion 20 is increased by the amount that the pipe overlapping portion 24 is connected to the protruding portion 23. The heat exchange performance is further improved in both the case where the heat exchanger 10 is used as an evaporator and the case where the heat exchanger 10 is used as a condenser. Further, the projecting portions 23 adjacent to each other in the X-axis direction face each other with the same interval as the interval between the main heat transfer portions 20 adjacent to each other in the X-axis direction. The dimension of the heat transfer tube 12 protruding outward from the protruding portion 23 is, for example, about 2 mm, but it can be changed as appropriate in addition to this value.

As shown in FIG. 3, the pipe overlapping portions 24 are connected to the protruding portions 23 adjacent to each other in the X-axis direction, and are arranged so as to coincide with the folded-back portion 21 in the X-axis direction. Therefore, the two protruding portions 23 connected to the overlapping pipe portion 24 and the two main heat transfer portions 20 connected to the folded-back portion 21 overlapping the overlapping pipe portion 24 in the X-axis direction are connected to each other. The pipe overlapping portion 24 has a substantially U-shape when viewed from the Y-axis direction, and one end portion is adjacent to one protruding portion 23 and the other end portion is adjacent to one protruding portion 23. They are connected to the protrusions 23, respectively. According to such a configuration, when the corrugated fin 13 is manufactured by, for example, bending a base material having a developed shape, a portion of the base material that constitutes a folded-back portion 21 and a pipe overlapping portion 24 are formed. It is excellent in productivity because it has a positional relationship in which the parts to be formed are lined up along the Y-axis direction. Moreover, the length of the pipe overlapping portion 24 from one end to the other end is equal to the length of the folded portion 21. The "length of the folded-back portion 21" referred to here is continuous from one end connected to one main heat transfer portion 20 to the other main heat transfer portion 20 adjacent to one main heat transfer portion 20. It is the length to the other end. In this way, when the corrugated fin 13 is manufactured, for example, when the base material of the developed shape is bent, the folded portion 21 and the pipe overlapping portion 24 are formed, and the folded portion 21 and the pipe overlapping portion 24 are formed. It suffices to bend the base material differently, and there is no need to cut off the base material. Therefore, it is possible to reduce chips generated by processing the base metal. As a result, a sufficient surface area of the corrugated fin 13 can be secured, so that the heat exchange performance can be improved both when the heat exchanger 10 is used as an evaporator and when it is used as a condenser. Is suitable.

As shown in FIG. 3, the pipe overlapping portions 24 are connected to the ends of the protruding portions 23 adjacent to each other in the X-axis direction in the Z-axis direction on the narrowly spaced side (folded portion 21 side). ing. Here, in the protruding portion 23, similarly to the main heat transfer portion 20, adjacent ones in the X-axis direction are inclined in opposite directions to each other. Therefore, the pipe overlapping portion 24 connected to the protruding portion 23 extends upward (one side) in the Z-axis direction from the protruding portion 23 and downwards (on the other side) in the Z-axis direction from the protruding portion 23. The ones to be put out and the ones to be put out are included, and these are arranged so as to be arranged alternately in the X-axis direction. All of these pipe overlapping portions 24 face outward in the Z-axis direction in the meandering corrugated fin 13 (the side opposite to the side from the pipe contact portion 25 described later toward the extending end of the subheat transfer portion 26). It extends from the protrusion 23. The corrugated fins 13 that are adjacent to each other in the Z-axis direction with the heat transfer tube 12 in between are in the X-axis direction so that the tube overlapping portions 24 that are in a positional relationship that overlaps with each other in the Z-axis direction are opposed to each other. The placement of is adjusted. The pipe overlapping portions 24 facing each other are arranged close to each other with a slight gap between them, and are not in contact with each other. That is, the pipe overlapping portion 24 has an extension dimension in the Z-axis direction that is less than half the thickness dimension of the heat transfer tube 12. Specifically, since the overlap margin of each pipe overlapping portion 24 with respect to the heat transfer tube 12 is, for example, about 0.9 mm, there is a gap of, for example, about 0.13 mm between the opposing pipe overlapping portions 24. Has been done. In addition to the above, specific numerical values regarding the overlap allowance of each pipe overlapping portion 24 with respect to the heat transfer tube 12 and the distance between the opposing pipe overlapping portions 24 can be appropriately changed. According to such a configuration, the heat exchanger 10 is used as an evaporator, and the condensed water generated on the surface of the main heat transfer portion 20 due to the heat exchange is discharged from the protruding portion 23 connected to the main heat transfer portion 20. After flowing to the pipe overlapping portion 24 on the lower side, the flow smoothly flows to the pipe overlapping portion 24 facing the pipe overlapping portion 24 at a space on the lower side. At this time, if the condensed water adhering to the surface of the upper pipe overlapping portion 24 grows to a size in contact with the lower pipe overlapping portion 24, the condensed water will flow to the lower pipe overlapping portion 24. Therefore, it is preferable to set the distance between the two overlapping portions 24 of the pipes facing each other as narrow as possible in order to promote smooth drainage. If drainage is promoted, the heat transfer efficiency between the air and the corrugated fin 13 is improved, and the heat exchange efficiency is improved. As a result, it becomes difficult for the heat transfer efficiency and the heat exchange efficiency to decrease due to the retention of the condensed water. Further, by providing a space between the pipe overlapping portions 24 facing each other, workability when assembling the heat transfer tube 12 and the corrugated fin 13 in the manufacture of the heat exchanger 10 is improved.

Then, as shown in FIG. 3, the folded-back portion 21 is opposite to the tube contact portion 25 that is in contact with the flat outer surface 12S of the heat transfer tube 12 and the main heat transfer portion 20 side of the tube contact portion 25. An auxiliary heat transfer portion 26 connected to a side end portion is provided. The pipe contact portion 25 and the sub-heat transfer portion 26 are arranged so as to overlap the pipe overlapping portion 24 in the X-axis direction. The tube contact portion 25 is formed substantially flat along the outer surface 12S of the heat transfer tube 12. The pipe contact portions 25 are arranged in pairs so as to be connected to the main heat transfer portions 20 adjacent to each other in the X-axis direction. The sub-heat transfer portions 26 are arranged in pairs so as to be connected to the paired pipe contact portions 25, respectively. The paired sub-heat transfer portions 26 extend along the Z-axis direction so as to be separated from the heat transfer tubes 12 which are the objects of contact of the continuous tube contact portions 25. The sub-heat transfer portion 26 constituting the folded-back portion 21 located on the lower side in the Z-axis direction of the corrugated fin 13 meandering up and down extends upward (one side) in the Z-axis direction from the pipe contact portion 25. On the other hand, the sub-heat transfer portion 26 constituting the folded-back portion 21 located on the upper side in the Z-axis direction extends downward (on the other side) from the pipe contact portion 25 in the Z-axis direction. The sub-heat transfer portions 26 extend inward in the Z-axis direction in the meandering corrugated fins 13, that is, extend from the pipe contact portion 25 to the side opposite to the extending side of the pipe overlapping portion 24 with respect to the protruding portion 23. There is. As shown in FIGS. 2 and 3, the pipe contact portion 25 and the sub-heat transfer portion 26 are provided so as to extend over substantially the entire length of the folded-back portion 21 in the Y-axis direction, respectively.

As described above, since the folded-back portion 21 is provided with the sub-heat transfer portion 26 in addition to the pipe contact portion 25, the surface area of the corrugated fin 13 is increased by the amount of the sub-heat transfer portion 26 as compared with the conventional case. It has increased. As a result, the heat exchange efficiency of the corrugated fin 13 is improved both when the heat exchanger 10 is used as an evaporator and when it is used as a condenser. If the heat exchange efficiency of the corrugated fins 13 is improved, the heat exchange performance of the heat exchanger 10 will be sufficient without precoating the surface of the corrugated fins 13 with a hydrophilic layer (hydrophilic resin layer). The vessel 10 can be applied to, for example, an outdoor unit of an air conditioner. Moreover, since the sub-heat transfer portion 26 is provided so as to form a part of the folded-back portion 21, the corrugated fin 13 is compared with the case where the sub-heat transfer portion is provided separately from the folded-back portion 21. The arrangement efficiency according to the above is improved, and the corrugated fin 13 can be easily manufactured. Further, since the tube contact portion 25 and the sub heat transfer portion 26 are both paired, heat exchange between the heat transfer tube 12 and the corrugated fin 13 is efficiently performed by the paired pipe contact portion 25. At the same time, heat exchange between the corrugated fin 13 and the air is performed by the sub heat transfer unit 26 which is a pair in addition to the main heat transfer unit 20. Compared to the case where one sub-heat transfer section is provided so as to be connected to only one of the paired tube contact portions 25, the extension length of the sub-heat transfer section 26 extending away from the heat transfer tube 12 is increased. Even if it is made small, a sufficient surface area related to the subheat transfer portion 26 can be secured.

The detailed configuration of the pipe contact portion 25 and the subheat transfer portion 26 will be described with reference to FIG. FIG. 4 is an enlarged cross-sectional view of the vicinity of the folded-back portion 21 constituting the corrugated fin 13. As shown in FIG. 4, the tube contact portion 25 extends from the main heat transfer portion 20 to the sub heat transfer portion 26 along the length direction (X-axis direction) of the heat transfer tube 12. It is in surface contact with the flat outer surface 12S of the heat tube 12. As a result, heat is efficiently transferred between the heat transfer tube 12 and the tube contact portion 25. The sub heat transfer portion 26 rises from the end of the tube contact portion 25 opposite to the main heat transfer portion 20 side, and extends away from the heat transfer tube 12. Here, the paired sub-heat transfer portions 26 are arranged so as to face each other so that a gap 51 is interposed between them. Specifically, although each sub-heat transfer portion 26 extends substantially along the Z-axis direction, it is slightly inclined with respect to the Z-axis direction, whereby a substantially triangular gap 51 when viewed from the Y-axis direction is formed. It is happening. The gap 51 interposed between the paired sub-heat transfer portions 26 communicates with the ventilation passage 50, and the air flowing through the ventilation passage 50 can enter and exit the gap 51. As a result, heat exchange is efficiently performed between the paired sub-heat transfer portions 26 and the air existing in the gap 51 interposed between them, so that the paired sub-heat transfer portions are in close contact with each other. The heat exchange performance is further improved as compared with the case where they are arranged facing each other. On top of that, the extension ends of the paired sub-heat transfer portions 26 are connected to each other. Specifically, the pipe contact portion 25 and the sub-heat transfer portion 26 (folded portion 21), which are paired with each other, have a substantially V shape when viewed from the Y-axis direction, and have a symmetrical shape as a whole. Since the paired sub-heat transfer portions 26 are connected to each other in this way, the mechanical of the paired sub-heat transfer portions 26 is compared with the case where the extending ends of the paired sub-heat transfer portions are not connected to each other. Strength increases. Therefore, since the paired sub-heat transfer portions 26 are less likely to be inadvertently deformed, the heat exchange performance of the paired sub-heat transfer portions 26 can be appropriately exhibited.

As shown in FIG. 4, the secondary heat transfer portion 26 is arranged so that its extending end is in a positional relationship of overlapping the end portion of the louver 22 in the Z-axis direction in the Z-axis direction. Specifically, the extending ends connected to each other in the paired sub heat transfer portions 26 and the cut-up base ends connected to the main heat transfer portion 20 in the louver 22 overlap each other in the Z-axis direction, and the X-axis. They are facing each other with a gap in the direction. Therefore, even if the louver 22 cut up from the main heat transfer portion 20 protrudes from the plate surface of the main heat transfer portion 20 toward the ventilation passage 50, there is a sufficient distance between the protruding portion and the sub heat transfer portion 26. Is vacant. As a result, interference between the louver 22 and the subheat transfer unit 26 is less likely to occur. Moreover, the lengths of the louver 22 and the sub-heat transfer portion 26 are both sufficiently large while avoiding mutual interference, so that high heat exchange performance is ensured.

As described above, the heat exchanger 10 of the present embodiment is a flat heat transfer tube 12 having a plurality of flow paths 12A inside, and a plurality of heat transfer tubes arranged at intervals so that the flat outer surfaces 12S face each other. A heat tube 12 and a corrugated fin 13 arranged between vertically adjacent heat transfer tubes 12 and extending while meandering are provided, and the corrugated fin 13 is arranged so as to cross between the adjacent heat transfer tubes 12. A pipe fitting having a plurality of main heat transfer portions 20 and a folded portion 21 connected to adjacent main heat transfer portions 20, and the folded portion 21 is in contact with a flat outer surface 12S of the heat transfer tube 12. A contact portion 25 and a sub heat transfer portion 26 extending away from the heat transfer tube 12 are provided at the end of the tube contact portion 25 on the side opposite to the main heat transfer portion 20 side.

In this way, the heat exchange between the heat transfer tube 12 having the plurality of flow paths 12A and the corrugated fin 13 is a tube contact provided in the folded-back portion 21 and abutting on the flat outer surface 12S of the heat transfer tube 12. It is done by part 25. The heat exchange between the corrugated fins 13 and the air extends away from the heat transfer tubes 12 provided at the folded-back portions 21 and the plurality of main heat transfer portions 20 arranged so as to cross between the adjacent heat transfer tubes 12. It is performed by the sub-heat transfer unit 26 that outputs. Therefore, as compared with the conventional case, the surface area of the corrugated fin 13 is increased by the amount of the sub-heat transfer portion 26, whereby the heat exchanger 10 is used as an evaporator and a condenser. The heat exchange performance of the corrugated fin 13 is improved in both cases. Moreover, since the sub-heat transfer portion 26 is provided in the folded-back portion 21 connected to the adjacent main heat-transferring portion 20, compared with the case where the sub-heat transfer portion is provided separately from the folded-back portion 21. The arrangement efficiency of the corrugated fins 13 is improved, and the corrugated fins 13 can be easily manufactured.

Further, the pipe contact portions 25 are arranged in pairs so as to be connected to the adjacent main heat transfer portions 20, and the sub heat transfer portions 26 are arranged in pairs so as to be connected to the paired pipe contact portions 25. It is arranged without any. In this way, the heat exchange between the heat transfer tube 12 and the corrugated fin 13 is performed by the paired tube contact portion 25, and the heat exchange between the corrugated fin 13 and the air is the adjacent main heat transfer. This is performed by the unit 20 and the paired sub-heat transfer unit 26. Compared to the case where one sub-heat transfer section is provided so as to be connected to only one of the paired tube contact portions 25, the extension length of the sub-heat transfer section 26 extending away from the heat transfer tube 12 is increased. Even if it is made small, a sufficient surface area related to the subheat transfer portion 26 can be secured.

Further, the paired sub-heat transfer portions 26 are arranged so as to face each other so that a gap 51 is interposed between them. In this way, heat exchange is performed between the paired sub-heat transfer portions 26 and the air existing in the gap 51 interposed between them. Therefore, the heat exchange performance is further improved as compared with the case where the paired sub-heat transfer portions are arranged so as to be in close contact with each other. The two paired sub-heat transfer portions 26 may be in close contact with each other without leaving a gap 51 between them.

Further, the extension ends of the paired sub-heat transfer portions 26 are connected to each other. In this way, the mechanical strength of the paired sub-heat transfer portions 26 is higher than that in the case where the extending ends of the paired sub-heat transfer portions are not connected. The portion 26 is less likely to be inadvertently deformed. As a result, the heat exchange performance of the paired sub-heat transfer portions 26 can be appropriately exhibited.

Further, the main heat transfer section 20 is provided with a louver 22 extending along the arrangement direction (Z-axis direction) of the heat transfer tube 12 and the corrugated fin 13, and the sub heat transfer section 26 is the extending end thereof. Is arranged so as to have an overlapping positional relationship with respect to the above-mentioned arrangement direction with respect to the end portion of the louver 22 with respect to the above-mentioned arrangement direction. In this way, the louver 22 improves the heat exchange efficiency in the main heat transfer unit 20. Since the louver 22 extends along the arrangement direction of the heat transfer tube 12 and the corrugated fin 13, the heat exchanger 10 is used as an evaporator, and condensed water is generated on the surface of the louver 22 due to the heat exchange. In this case, the condensed water can be efficiently flowed along the above-mentioned arrangement direction, and retention can be made less likely to occur. As a result, the heat transfer efficiency between the air and the corrugated fin 13 is improved, and the heat exchange performance is improved. Further, since the extension end of the secondary heat transfer unit 26 is arranged so as to have an overlapping positional relationship with respect to the end portion in the alignment direction of the louver 22 in the above-mentioned alignment direction, the louver 22 and the secondary heat transfer portion 26 are arranged. It is possible to secure a sufficiently large length of the heat transfer unit 26 to ensure high heat exchange performance, and to prevent interference between the louver 22 and the sub heat transfer unit 26.

Further, the main heat transfer unit 20 has a protrusion 23 that protrudes outward in the width direction (Y-axis direction), which is the direction in which the plurality of flow paths 12A are lined up with respect to the heat transfer tube 12, and the protrusion 23 has a protrusion 23. , Regarding the arrangement direction (Z-axis direction) of the heat transfer tube 12 and the corrugated fin 13, extending from the tube contact portion 25 toward the side opposite to the side toward the extension end of the sub heat transfer portion 26, and regarding the above-mentioned arrangement direction A pipe overlapping portion 24 is provided so as to have a positional relationship of overlapping with the heat transfer tube 12. In this way, the surface area of the main heat transfer portion 20 is increased by the amount of the protrusion portion 23 that protrudes outward in the width direction with respect to the heat transfer tube 12, so that the heat exchange performance is further improved. On top of that, the pipe overlapping portion 24 provided in the protruding portion 23 is on the opposite side of the arrangement direction of the heat transfer pipe 12 and the corrugated fin 13 from the pipe contact portion 25 toward the extending end of the sub heat transfer portion 26. Since it is arranged so as to extend toward the above direction and overlap with the heat transfer tube 12 in the above-mentioned arrangement direction, the heat exchanger 10 is used as an evaporator, and the surface of the main heat transfer unit 20 is used as the heat is exchanged. Even when condensed water is generated in the water, the condensed water can be efficiently flowed through the protruding portion 23 and the pipe overlapping portion 24, and the retention of the condensed water can be suppressed. As a result, the heat transfer efficiency between the air and the corrugated fin 13 due to the retention of the condensed water and the heat exchange efficiency are less likely to decrease. Further, in the case of manufacturing the corrugated fin 13, for example, when the base material having a developed shape is bent, the portion of the base material that constitutes the folded-back portion 21 and the portion that constitutes the pipe overlapping portion 24 are described above. It is highly productive because it is arranged in the width direction.

Further, the folded-back portion 21 and the pipe overlapping portion 24 have the same length. In the case of manufacturing the corrugated fin 13, for example, when the base material of the developed shape is bent, if the lengths of the folded portion 21 and the pipe overlapping portion 24 are equal, the chips generated by the processing of the base material are generated. Can be reduced. As a result, a sufficient surface area of the corrugated fin 13 can be secured, which is suitable for improving the heat exchange performance.

<Embodiment 2>
The second embodiment will be described with reference to FIG. 5 or FIG. In the second embodiment, the configuration of the sub-heat transfer unit 126 is changed. The duplicate description of the structure, action, and effect similar to that of the first embodiment will be omitted.

As shown in FIG. 5, the subheat transfer unit 126 according to the present embodiment has a cantilever shape so that the extending end is a free end. Specifically, the sub heat transfer portions 126 that are connected to the paired pipe contact portions 125 and are arranged so as to face each other with a gap 51 between them, but the extending ends of each other may be continuous. do not have. Therefore, as compared with the case where the extending ends of the paired sub-heat transfer portions 26 are connected to each other as in the first embodiment (see FIG. 3), there is a gap between the pair of sub-heat transfer portions 126. The degree of freedom of setting related to the size of 51 is increased. This makes it possible to secure a sufficiently large gap 51 interposed between the paired sub-heat transfer portions 126, which is suitable for further improving the heat exchange performance. Further, as compared with the first embodiment described above, when the heat exchanger 110 is used as an evaporator and condensed water is generated on the surface of the subheat transfer unit 126 due to the heat exchange, the condensed water is less likely to stay. , The decrease in heat transfer efficiency between the air and the corrugated fin 113 due to the retention of condensed water and the decrease in heat exchange efficiency are less likely to occur.

As shown in FIG. 6, the pipe contact portion 125 connected to the subheat transfer portion 126 has a shorter length extending along the flat outer surface 112S of the heat transfer tube 112 as compared with the first embodiment described above. There is. Therefore, the gap 51 formed between the pair of sub-heat transfer portions 126 is wider than that of the first embodiment described above. As a result, the heat exchange efficiency between the paired sub-heat transfer portions 126 and the air existing in the ventilation passage 50 is improved. Specifically, the paired sub-heat transfer portions 126 are inclined so that the gap 51 gradually narrows as it approaches the extending end (free end). The minimum value of the gap 51, that is, the distance between the extending ends of the paired sub-heat transfer portions 126 is wider than the distance between the sub-heat transfer portions 126 and the louver 122.

As described above, according to the present embodiment, the paired sub-heat transfer portions 126 each have a cantilever shape so that the extending end is a free end. In this way, since each of the paired sub-heat transfer portions 126 has a cantilever shape, the extending ends of the pair do not extend to each other. Therefore, as compared with the case where the extending ends of the paired sub-heat transfer portions are connected to each other, the degree of freedom in setting the size of the gap 51 interposed between the pair of sub-heat transfer portions 126 is increased. This makes it possible to secure a sufficiently large gap 51 interposed between the paired sub-heat transfer portions 126, which is suitable for further improving the heat exchange performance. Further, as compared with the case where the extending ends of the paired sub-heat transfer portions are connected to each other, the heat exchanger 110 is used as an evaporator, and condensed water is generated on the surface of the sub-heat transfer portion 126 due to the heat exchange. In this case, the condensed water is less likely to stay, and the heat transfer efficiency and heat exchange efficiency between the air and the corrugated fin 113 due to the retention of the condensed water are less likely to decrease. The two paired sub-heat transfer portions 126 may be in close contact with each other without leaving a gap 51 between them. Further, the two free ends of the two sub-heat transfer portions 126 that form a pair may be in contact with each other. Further, the paired secondary heat transfer portions 126 may have different extension lengths (rising heights). Further, the lengths of the folded-back portion 121 and the pipe overlapping portion 124 may be the same, but may be different.

<Embodiment 3>
The third embodiment will be described with reference to FIGS. 7 to 9. In the third embodiment, a positioning structure for positioning the heat transfer tube 212 and the corrugated fin 213 is added from the first embodiment. The duplicate description of the structure, action, and effect similar to that of the first embodiment will be omitted.

As shown in FIGS. 7 and 8, the heat transfer tube 212 and the corrugated fin 213 according to the present embodiment are provided with a positioning structure for positioning each other in the Y-axis direction by uneven fitting. The positioning structure is provided on the surface of the heat transfer tube 212 facing the corrugated fin 213 with respect to the heat transfer tube side positioning portion 27 and the heat transfer tube side positioning portion 27 of the corrugated fin 213 with respect to the heat transfer tube side positioning portion 27. It is composed of a fin-side positioning portion 28 that is fitted in a concave-convex shape. In the present embodiment, the corrugated fin 213 does not contain a brazing material, and the heat transfer tube 212 and the corrugated fin 213 are fixed to each other via an adhesive. This adhesive may be pre-coated on the corrugated fins 213, but it may also be applied to the corrugated fins 213 before assembling the heat transfer tube 212 and the corrugated fins 213. I do not care. In the former case, the adhesive clad on the core material is melted and fixed by being placed in a furnace at a lower temperature (for example, about 100 ° C. to 200 ° C.) than the high temperature (for example, about 600 ° C.) furnace at the time of brazing. Can be planned. When the manufacturing method of fixing the heat transfer tube 212 and the corrugated fin 213 using an adhesive in this way is adopted, the heat transfer tube side positioning is performed when the heat transfer tube 212 and the corrugated fin 213 are assembled prior to the fixing by the adhesive. By fitting the portion 27 and the fin-side positioning portion 28 in an uneven manner, the heat transfer tube 212 and the corrugated fin 213 can be appropriately positioned in the Y-axis direction. As a result, workability can be improved. Further, even when the adhesive loses its function due to aged deterioration, it is possible to obtain an effect that the position shift between the heat transfer tube 212 and the corrugated fin 213 is less likely to occur. When the heat transfer tube 212 and the corrugated fin 213 are fixed to each other using an adhesive as described above, the heat transfer tube 212 can be fixed to the header tube using an adhesive. In that case, as a member used for the header pipe, it is possible to use a non-clad material in which the brazing material is not clad to the core material.

As shown in FIGS. 7 and 8, the heat transfer tube side positioning portion 27 is arranged at the center position of the heat transfer tube 212 in the width direction (Y-axis direction), and the flat outer surface 212S is locally arranged in the Z-axis direction. It is formed by denting along the shape and has a concave shape. The heat transfer tube side positioning unit 27 is provided on each of the two upper and lower flat outer surfaces 212S of the heat transfer tube 212. The heat transfer tube side positioning portion 27 is formed in a groove shape extending over the entire length along the length direction (X-axis direction) of the heat transfer tube 212. If the heat transfer tube side positioning portion 27 has a concave shape in this way, when the heat transfer tube 212 is wound for transportation or storage after being manufactured by extrusion processing, the heat transfer tube side positioning portion 27 is wound. It can be avoided to get in the way. Specifically, if the heat transfer tube side positioning portion has a convex shape, the heat transfer tube side positioning portion may interfere with the outer surface of the heat transfer tube 212 during winding and damage the heat transfer tube. If the side positioning portion 27 has a concave shape, the above-mentioned interference can be avoided. This is suitable for improving the productivity of the heat transfer tube 212. As the heat transfer tube side positioning portion 27 is recessed on the outer surface 212S of the heat transfer tube 212, among the plurality of flow paths 212A, those having a positional relationship that overlaps with the heat transfer tube side positioning portion 27 in the Y-axis direction do not overlap. It is narrower in the Z-axis direction than the one. The recessed dimension of the heat transfer tube side positioning portion 27 is about 0.3 mm, but it can be changed as appropriate in addition to this value.

As shown in FIGS. 7 and 8, the fin-side positioning portion 28 is arranged at the center position of the corrugated fin 213 in the Y-axis direction, and the main heat transfer portion 220 locally protrudes along the Z-axis direction. It is formed by making it convex and has a convex shape. The fin-side positioning portions 28 are provided on the upper and lower two edges of the main heat transfer portion 220, respectively. As such a fin-side positioning portion 28 is provided on the corrugated fin 213, the folded-back portion 221 is selectively selected as a non-formed portion of the fin-side positioning portion 28 in the Y-axis direction as shown in FIGS. 8 and 9. It is provided in the above, and is divided into two by the fin-side positioning portion 28. The fin-side positioning portion 28 is connected to the non-formed portion of the folded-back portion 221 of the main heat transfer portion 220, and is sandwiched from both sides by the two folded-back portions 221. Such fin-side positioning portions 28 are provided in all main heat transfer portions 220 provided in the corrugated fins 213. Therefore, on the heat transfer tube side positioning portion 27 extending over the entire length of the heat transfer tube 212, a plurality of fin side positioning portions 28 provided on each of the plurality of main heat transfer portions 220 of the corrugated fins 213 are collectively uneven. It is designed to be fitted. The protruding dimension of the fin-side positioning portion 28 is smaller than the recessed dimension of the heat transfer tube-side positioning portion 27, and is set to, for example, about 0.2 mm, but other than this value can be appropriately changed.

As described above, according to the present embodiment, the heat transfer tube side positioning portion 27 is provided on the surface of the heat transfer tube 212 facing the corrugated fin 213, whereas the surface of the corrugated fin 213 facing the heat transfer tube 212. Is provided with a fin-side positioning portion 28 that is unevenly fitted to the heat transfer tube-side positioning portion 27. In this way, when the heat transfer tube 212 and the corrugated fin 213 are assembled, the heat transfer tube side positioning portion 27 and the fin side positioning portion 28 are unevenly fitted, so that the heat transfer tube 212 and the corrugated fin 213 can be brought together. Positioning can be achieved. In particular, workability can be improved when the heat transfer tube 212 and the corrugated fin 213 are fixed by the adhesive precoated on the heat transfer tube 212.

Further, the heat transfer tube side positioning portion 27 has a concave shape, while the fin side positioning portion 28 has a convex shape. In this way, when the heat transfer tube 212 is wound in the manufacture of the heat transfer tube 212, the concave heat transfer tube side positioning portion 27 does not interfere with the outer surface of the heat transfer tube 212, and the heat transfer tube side positioning portion 27 It is avoided that it interferes with winding. This is suitable for improving the productivity of the heat transfer tube 212.

<Embodiment 4>
The fourth embodiment will be described with reference to FIGS. 10 to 12. In the fourth embodiment, the concave-convex relationship of the positioning structure is reversed from the third embodiment. It should be noted that duplicate description of the same structure, action and effect as in the third embodiment will be omitted.

As shown in FIGS. 10 and 11, the heat transfer tube side positioning portion 327 constituting the positioning structure according to the present embodiment is formed by locally projecting the flat outer surface 312S along the Z-axis direction. It has a convex shape. The heat transfer tube side positioning portion 327 is formed in a ridge shape extending over the entire length along the length direction of the heat transfer tube 312. In this way, the flat outer surface 312S of the heat transfer tube 312 can be prevented from being dented as in the second embodiment, so that the plurality of internal flow paths 312A are almost all substantially the same as in the first embodiment. Can be kept the same size. The protruding dimension of the heat transfer tube side positioning portion 327 is about 0.2 mm, but it can be changed as appropriate in addition to this value.

The fin-side positioning portion 328 is formed by locally denting the main heat transfer portion 320 along the Z-axis direction, as shown in FIGS. 10 and 11 (A-A line cross section of FIG. 10). It has a concave shape. As shown in FIGS. 11 and 12, the fin-side positioning portion 328 is selectively formed in the non-formed portion of the folded-back portion 321 divided into two in the main heat transfer portion 320. The recessed dimension of the fin-side positioning portion 328 is larger than the protruding dimension of the heat transfer tube-side positioning portion 327, and is set to, for example, about 0.3 mm, but other than this value can be appropriately changed.

As described above, according to the present embodiment, the heat transfer tube side positioning portion 327 has a convex shape, while the fin side positioning portion 328 has a concave shape. In this way, if the fin-side positioning portion is convex, the heat transfer tube-side positioning portion must be concave, but this can be avoided. As a result, it is possible to prevent the flat outer surface 312S of the heat transfer tube 312 from being dented, so that it is not necessary to change the internal flow path 312A due to the heat transfer tube side positioning portion 327.

<Embodiment 5>
The fifth embodiment will be described with reference to FIG. In the fifth embodiment, the arrangement of the pipe overlapping portion 424 is changed from the first embodiment described above. The duplicate description of the structure, action, and effect similar to that of the first embodiment will be omitted.

In the corrugated fins 413 according to the present embodiment, as shown in FIG. 13, pipe overlapping portions 424 facing vertically in the Z-axis direction are arranged so as to come into contact with each other without a gap between them. In this way, when the heat exchanger 410 is used as an evaporator and condensed water is generated on the surface of the main heat transfer section 420 due to the heat exchange, the condensed water is connected to the main heat transfer section 420. After flowing from the protruding portion 423 to the pipe overlapping portion 424 on the lower side thereof, the flow flows more smoothly to the pipe overlapping portion 424 located below the pipe overlapping portion 424 and in contact with the pipe overlapping portion 424. As a result, the retention of condensed water is less likely to occur, so that the heat transfer efficiency and the heat exchange efficiency between the air and the corrugated fin 413 are less likely to decrease.

<Embodiment 6>
The sixth embodiment will be described with reference to FIG. In the sixth embodiment, the arrangement of the pipe overlapping portion 524 is changed from the above-described first embodiment. The duplicate description of the structure, action, and effect similar to that of the first embodiment will be omitted.

As shown in FIG. 14, the corrugated fins 513 adjacent to each other in the Z-axis direction with the heat transfer tube 512 according to the present embodiment are arranged so that the overlapping portions 524 of the tubes are offset from each other without overlapping in the X-axis direction. .. The pipe overlapping portion 524 arranged on one side in the Z-axis direction and the pipe overlapping portion 524 arranged on the other side of the heat transfer tube 512 are not opposed to each other and are separated from each other in the X-axis direction. It is considered to be an arrangement. The distance in the X-axis direction between the pipe overlapping portion 524 on one side and the pipe overlapping portion 524 on the other side is the distance (arrangement pitch) between the pipe overlapping portions 524 on one side adjacent to each other in the X-axis direction and X. It is about half the distance between the pipe overlapping portions 524 on the other side adjacent to each other in the axial direction. The relative positional relationship between the pipe overlapping portion 524 arranged on one side in the Z-axis direction and the pipe overlapping portion 524 arranged on the other side of the heat transfer tube 512 in the Z-axis direction is appropriate. Can be changed to. For example, the pipe overlapping portion 524 arranged on one side in the Z-axis direction across the heat transfer tube 512 and the pipe overlapping portion 524 arranged on the other side may not overlap in the Z-axis direction. , The positional relationship that overlaps in the Z-axis direction may be used.

<Embodiment 7>
Embodiment 7 will be described with reference to FIG. In the seventh embodiment, the number of the protruding portion 623 and the pipe overlapping portion 624 is changed from the above-described first embodiment. The duplicate description of the structure, action, and effect similar to that of the first embodiment will be omitted.

As shown in FIG. 15, the protruding portions 623 according to the present embodiment are provided in pairs so as to be connected to both ends of the main heat transfer portion 620 in the Y-axis direction. A pair of pipe overlapping portions 624 are provided in each of the pair of protruding portions 623. The corrugated fin 613 has a symmetrical shape when viewed from the X-axis direction. According to such a configuration, the flow of the condensed water is further promoted by the pair of protruding portions 623 and the pair of pipe overlapping portions 624 connected to them, and the retention of the condensed water is less likely to occur. As a result, the heat transfer efficiency between the air and the corrugated fin 613 is improved, and the heat exchange performance is improved. By forming the corrugated fins 613 in a symmetrical shape in this way, the complexity in production is eliminated, and it becomes easy to manage the heat exchangers in the right-right orientation when assembling the heat exchanger.

<Other Embodiments>
The techniques disclosed herein are not limited to the embodiments described above and in the drawings, and for example, the following embodiments are also included in the technical scope.

(1) Regarding the joining of the header tube, the heat transfer tube, the corrugated fin, and the side sheet, the joining may be performed by a hydraulic expansion tube in addition to brazing or fixing with an adhesive. In that case, if a side sheet having the same flow path as the heat transfer tube is used, the side sheet and the corrugated fin can be joined by the hydraulic expansion tube.

(2) A hydrophilic layer (hydrophilic resin layer) may be precoated on the surface of the corrugated fin. Since the surface tension of the corrugated fin is reduced by the hydrophilic layer, the flow of the condensed water is promoted, which is suitable for preventing the retention of the condensed water. When the hydrophilic layer is precoated on the corrugated fin, it is preferable to use an adhesive that can be fixed at a low temperature as in the above-mentioned embodiments 3 and 4.

(3) The sub-heat transfer portion may be arranged so that its extending end is offset in the Z-axis direction with respect to the end portion in the louver in the Z-axis direction. In this way, it is possible to avoid the situation where the louver and the subheat transfer unit interfere with each other with high certainty.

(4) The two paired sub-heat transfer portions may extend straight along the Z-axis direction. Further, the two paired secondary heat transfer portions may be inclined so as to maximize the distance between the extending ends. In addition to these, the specific shape of the paired secondary heat transfer portions can be changed as appropriate.

(5) The two paired sub-heat transfer portions may be in close contact with each other without leaving a gap between them.

(6) The positioning structure of the third and fourth embodiments is not limited to the case where the heat transfer tube and the corrugated fin are fixed by using an adhesive, and the heat transfer tube and the corrugated fin are brazed as in the first and second embodiments. It can also be applied when fixing with.

(7) The number of installations of the positioning structures of the third and fourth embodiments can be changed as appropriate.

(8) Only one sub-heat transfer portion may be provided for one folded portion so as to be connected to only one of the paired pipe contact portions.

(9) Only one tube contact portion may be provided for one folded portion so as to be connected to only one of the adjacent main heat transfer portions. In that case, only one sub-heat transfer portion is provided for each folded portion.

(10) The protruding portion may be selectively arranged on the upstream side of the air flow in the Y-axis direction of the main heat transfer portion.

(11) The louver may be formed by, for example, partially knocking out the main heat transfer portion, in addition to cutting and raising.

(12) The louvers may be arranged so that the extending directions intersect with each other in the Z-axis direction. For example, the extending direction of the louver may coincide with the Y-axis direction, or may be tilted with respect to the Z-axis direction and the Y-axis direction.

(13) The number of folding backs and the folding back cycle of the corrugated fins can be changed as appropriate.

(14) In the configuration described in the first, second, fifth, sixth, and seventh embodiments (the configuration without the positioning structure), the header tube, the heat transfer tube, the corrugated fin, and the side sheet are joined by fixing with an adhesive. It doesn't matter.

(15) Specific members used for the header tube, heat transfer tube, corrugated fin, and side sheet can be appropriately changed such as a clad material (including a single-sided clad material and a double-sided clad material) and a non-clad material.

10, 110, 410 ... Heat exchanger, 12, 112, 212, 312, 512 ... Heat transfer tube, 12A, 212A, 312A ... Flow path, 12S, 112S, 212S, 312S ... Outer surface, 13, 113, 213, 413 ... 513,613 ... Corrugated fins, 20,220,320,420,620 ... Main heat transfer section, 21,121,221,321 ... Folded section, 22,122 ... Louver, 23,423,623 ... Protruding section, 24, 124,424,524,624 ... Tube overlapping part, 25,125 ... Tube contact part, 26,126 ... Secondary heat transfer part, 27,327 ... Heat transfer tube side positioning part, 28,328 ... Fin side positioning part, 51 …gap

Claims (11)

A flat heat transfer tube having a plurality of flow paths inside, and a plurality of heat transfer tubes arranged at intervals so that the flat outer surfaces face each other.
It is equipped with corrugated fins that meander and extend between the adjacent heat transfer tubes.
The corrugated fin has a plurality of main heat transfer portions arranged so as to cross between the adjacent heat transfer tubes, and a folded portion connected to the adjacent main heat transfer portions, and the folded portion has a folded portion. , The tube contact portion that comes into contact with the flat outer surface of the heat transfer tube and the end portion of the tube contact portion that is opposite to the main heat transfer portion side and extends away from the heat transfer tube. A heat exchanger provided with an auxiliary heat transfer unit. The pipe contact portions are arranged in pairs so as to be connected to the adjacent main heat transfer portions.
The heat exchanger according to claim 1, wherein the sub-heat transfer portions are arranged in pairs so as to be connected to the paired pipe contact portions. The heat exchanger according to claim 2, wherein the paired sub-heat transfer portions are arranged so as to face each other so that a gap is interposed between them. The heat exchanger according to claim 2 or 3, wherein the paired sub-heat transfer portions are connected to each other at the extending ends. The heat exchanger according to claim 2 or 3, wherein the paired sub-heat transfer portions are cantilevered so that the extending end is a free end. The main heat transfer portion is provided with a louver extending along the arrangement direction of the heat transfer tube and the corrugated fins.
Any one of claims 1 to 5, wherein the subheat transfer portion is arranged so that its extending end overlaps with respect to the end portion of the louver in the alignment direction. The heat exchanger according to item 1. The main heat transfer portion has a protruding portion that protrudes outward in the width direction, which is the direction in which the plurality of the flow paths are arranged with respect to the heat transfer tube.
The heat transfer tube and the corrugated fin extend toward the protruding portion from the tube contact portion to the side opposite to the side toward the extension end of the sub heat transfer portion, and the alignment direction is described as described above. The heat exchanger according to any one of claims 1 to 6, wherein a tube overlapping portion is provided so as to have a positional relationship of overlapping with the heat transfer tube. The heat exchanger according to claim 7, wherein the folded portion and the overlapping portion of the pipes have the same length. The heat transfer tube side positioning portion is provided on the surface of the heat transfer tube facing the corrugated fin, whereas the surface of the corrugated fin facing the heat transfer tube is uneven with respect to the heat transfer tube side positioning portion. The heat exchanger according to any one of claims 1 to 8, wherein a fin-side positioning portion to be fitted is provided. The heat exchanger according to claim 9, wherein the heat transfer tube side positioning portion has a concave shape, whereas the fin side positioning portion has a convex shape. The heat exchanger according to claim 9, wherein the heat transfer tube side positioning portion has a convex shape, whereas the fin side positioning portion has a concave shape.

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