JP2019190727A - Heat exchanger - Google Patents

Abstract

To solve such the problem that a condition, such as a cold district or severe winter season, where frosting is likely to occur obstructs suppression of frosting and generates air occlusion, increases draft resistance, reduces an air volume passing through a heat exchanger and results in deterioration in heat exchange performance.SOLUTION: A plate-like fin 11 including a flat part 14, a tube insertion cutout part 16 and a collar part 17 is provided with a forward edge cutout part 18 from at least part of a side face upstream of an air flow of a flat tube 12 that is inserted into the tube insertion cutout part 16, to the flat part 14.SELECTED DRAWING: Figure 2

Description

  The present invention is composed of a plurality of plate-like fins and a plurality of flat tubes having a plurality of refrigerant channels, and the air flowing between the plurality of fins and the refrigerant channels of the plurality of flat tubes The present invention relates to a heat exchanger that performs heat exchange with a flowing refrigerant.

  Conventionally, it is composed of a plate-shaped fin and a plurality of flat tubes provided at right angles with a plurality of refrigerant flow paths provided in a pipe insertion notch provided in parallel to each other on the air flow downstream side of the fin. Heat exchangers are known.

  In this type of heat exchanger, a heat exchanger in which flat portions are provided on fins is disclosed (for example, see Patent Document 1).

  FIG. 17 is a fin plan view of the xy plane of the conventional heat exchanger described in Patent Document 1, where the x direction is the air flow direction and the y direction is the flat tube arrangement direction.

  As shown in FIG. 17, the heat exchanger 1 includes a plurality of refrigerant flow paths in the plate-like fins 2 and the tube insertion notches 3 provided in parallel to each other on the air flow downstream side (+ x direction) of the fins 2. 4 and a plurality of flat tubes 5 inserted at right angles, and a flat portion 6 is provided on the air flow upstream side (−x direction) of the tube insertion notch 3 of the fin 2.

  As a result, the distance from the flat tube 5 to the front edge portion of the fin 2 becomes long. Therefore, when used in an environment where frost formation occurs, the amount of humidity in the air from the refrigerant flowing through the refrigerant flow path 4 of the flat tube 5 Therefore, heat transfer to the air flow upstream side (−x direction) of the fin 2 where frost formation is likely to occur becomes dull, and air blockage due to frost formation can be suppressed.

JP 2012-233680 A

  However, in the conventional configuration, in conditions where frost formation is more likely to occur such as in cold districts and severe winter seasons, it is still insufficient to sufficiently suppress frost formation, air blockage occurs, ventilation resistance increases, Since the amount of air passing through the heat exchanger is reduced, there is a problem that the heat exchange performance is reduced.

  The present invention solves the above-mentioned conventional problems, and in a heat exchanger using a flat tube, the fin efficiency on the upstream side of the air flow is reduced, and frost formation on the upstream side of the air flow of the fin is suppressed, while the flatness is reduced. It aims at providing the heat exchanger which can improve heat exchange performance by promoting the heat transfer in the air flow upstream of a pipe.

In order to solve the above-described conventional problems, the heat exchanger of the present invention includes a plurality of plate-like fins arranged at a predetermined interval and a plurality of flat tubes provided with a plurality of refrigerant channels. In the heat exchanger, the fin includes a flat part, pipe insertion notches formed in parallel to each other for inserting the flat pipe downstream of the air flow, and a collar part for contacting the flat pipe. A front edge notch portion is provided in the flat portion from at least a part of the air flow upstream side surface of the flat tube that is configured and inserted in the tube insertion notch portion.

  Thereby, at least a part of the air flow upstream side surface of the flat tube is not in contact with the fin, and air is interposed between the air flow upstream side surface of the flat tube and the fin, so that the air flow upstream side of the flat tube Heat transfer from the side surface to the front edge of the fin becomes dull.

  The heat exchanger of the present invention can suppress the occurrence of frost formation on the fins on the upstream side of the air flow with a large amount of humidity in the air, even in conditions where frost formation is more likely to occur in cold regions and severe winter seasons. A decrease in the amount of air passing through the heat exchanger due to an increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

The perspective view of the heat exchanger of Embodiment 1 of this invention Fin plane view of the xy plane of the heat exchanger of Embodiment 1 of the present invention The fin side surface of the yz plane which looked at the heat exchanger of Embodiment 1 of this invention from the x direction Top view showing the internal structure of an outdoor unit to which a heat exchanger is applied Front view showing the internal structure of an outdoor unit to which a heat exchanger is applied Fin plane view of xy plane of heat exchanger in Embodiment 2 of the present invention The fin enlarged view of the xy plane of the heat exchanger in Embodiment 2 of this invention Fin plane view of the xy plane of the heat exchanger in the first modification of the second embodiment of the present invention Fin plane view of the xy plane of the heat exchanger in Modification 2 of Embodiment 2 of the present invention Fin of xy plane of heat exchanger in modification 3 of embodiment 2 of the present invention Fin of xy plane of heat exchanger in modification 4 of embodiment 2 of the present invention Fin of xy plane of heat exchanger in modification 5 of embodiment 2 of the present invention Fin of xy plane of heat exchanger in modification 6 of embodiment 2 of the present invention Fin plane view of xy plane of heat exchanger in Embodiment 3 of the present invention Fin of xy plane of heat exchanger in modification 1 of embodiment 3 of the present invention Fin of xy plane of heat exchanger in modification 2 of embodiment 3 of the present invention Fin plane view of xy plane of conventional heat exchanger

  A first invention is a heat exchanger including a plurality of plate-like fins arranged at predetermined intervals and a plurality of flat tubes provided with a plurality of refrigerant flow paths. A flat tube inserted into the tube insertion notch, comprising a tube insertion notch formed in parallel to each other for inserting the flat tube downstream of the air flow, and a collar for contacting the flat tube. A leading edge notch is provided in the flat portion from at least a part of the air flow upstream side surface of the pipe.

Thereby, at least a part of the air flow upstream side surface of the flat tube is not in contact with the fin, and air is interposed between the air flow upstream side surface of the flat tube and the fin, so that the air flow upstream side of the flat tube Heat transfer from the side surface to the front edge of the fin becomes dull.

  Therefore, even in conditions where frost formation is more likely to occur, such as in cold regions and severe winters, it is possible to suppress the formation of frost on the fins on the upstream side of the air flow with a high amount of humidity in the air. A decrease in the amount of air passing through the exchanger is suppressed, and heat exchange performance can be improved.

  Also, since at least a part of the collar part of the fin is cut and the air is in direct contact with the air flow upstream side surface of the flat tube, heat transfer on the air flow upstream side of the flat tube can be promoted, and the heat exchanger performance is improved. This can be further improved.

  According to the second aspect of the present invention, when the flat tube side opening width of the leading edge notch is h and the height of the flat tube is H, the leading edge notch is provided such that h <H.

  As a result, the height of the flat tube is larger than the flat tube side opening of the leading edge notch, and when the flat tube is inserted, the flat tube contacts and is fixed at the flat tube side opening of the leading edge notch. Is done.

  Therefore, since a predetermined amount of a plurality of flat tubes can be inserted, during low-air heating operation, due to variations in the amount of flat tubes inserted, the temperature locally decreases at the front edge portion of the fin and frost formation occurs. This can be suppressed, and a decrease in the amount of air passing through the heat exchanger due to an increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

3rd invention provides the drainage notch part containing the gravity direction component in the front edge notch part.
As a result, the condensed water that is generated upstream of the air flow of the flat tube and flows into the leading edge notch flows along the drain notch, grows downward in the direction of gravity, increases the amount of moisture, and forms condensed water. As the gravity increases, it flows down quickly.

  Therefore, even during high-load operation where the amount of condensed water generated is large, it is possible to suppress the remaining dew condensation water, to prevent a decrease in the amount of air passing through the heat exchanger due to an increase in ventilation resistance, and heat exchange performance Can be improved.

  Moreover, since the condensed water flows down quickly without freezing during the low outside air temperature heating operation, it is possible to prevent the heat exchanger from freezing and stop the heating operation, thereby improving the heating capacity.

  In addition, since the fins are cut by the drainage notches, heat transfer from the airflow upstream side surface of the flat tube to the front edge of the fins becomes dull, so even in conditions where frost formation is likely to occur, the amount of humidity in the air Therefore, the occurrence of frost formation on the fins on the upstream side of the air flow can be suppressed, the decrease in the amount of air passing through the heat exchanger due to the increase in ventilation resistance is suppressed, and the heat exchange performance can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a perspective view of a heat exchanger according to Embodiment 1 of the present invention, where the x direction is the air flow direction, the y direction is the flat tube arrangement direction, and the z direction is the fin arrangement direction.

In FIG. 1, the heat exchanger 10 includes a plurality of plate-like fins 11 arranged at a predetermined interval, and a plurality of flat tubes 12 inserted at right angles to the plurality of fins 11 and arranged parallel to each other. The heat exchange is performed between the air flowing between the plurality of fins 11 and the refrigerant flowing in the plurality of refrigerant channels 13 formed in the plurality of flat tubes 12.

  In addition, as a refrigerant | coolant, the mixed refrigerant | coolant containing R410A, R32, and R32 etc. are used, for example.

  2 is a fin plan view of the xy plane of the heat exchanger according to the first embodiment of the present invention, and FIG. 3 is a zy plane when the heat exchanger of the first embodiment of the present invention is viewed from the x direction. It is a fin side view of this, and is AA sectional drawing of FIG.

  The fin 11 includes a flat portion 14, a heat transfer promoting portion 15, a tube insertion notch portion 16 formed in parallel to each other for inserting the flat tube 12 on the downstream side (+ x direction), and the flat tube 12. The front edge provided toward the flat portion 14 from at least a part of the side surface of the collar portion 17 for contact and the air flow upstream side (−x direction) of the flat tube 12 inserted into the tube insertion notch portion 16. And a notch 18.

  The heat transfer promoting part 15 rises from the flat part 14 of the fin 11 toward the air flow path side (+ z direction), is formed in a mountain shape, and between the adjacent flat tubes 12, and It is provided between the front edge of the flat tube 12 and the rear edge of the flat tube 12.

  The opening of the tube insertion notch 16 is larger than the height (y-direction length) of the flat tube 12 so that the flat tube 12 can be easily inserted.

  The collar portion 17 rises from the flat portion 14 of the fin 11 at a substantially right angle toward the air flow path side (+ z direction), is brought into contact with the surface of the adjacent fin 11, and maintains the interval between the adjacent fins 11. ing. The flat tube 12 is joined by brazing.

  In addition, the space | interval of the adjacent fin 11 may be hold | maintained by making the collar part 17 not contacting the surface of the adjacent fin 11 but making a different raising part, such as a tab (not shown), in the collar part 17 contact. .

  Next, the air flow will be described. A part of the air flowing into the heat exchanger 10 collides with the front edge portion of the fin 11, and a part passes between the adjacent fins 11 without colliding with the fin 11.

  At the front edge portion of the fin 11, air collides and the boundary layer becomes thin, so that the heat transfer coefficient is increased. The air that has collided with the front edge of the fin 11 passes between the adjacent fins 11.

  A part of the air flowing between the adjacent fins 11 flows so as to collide with the flat tube 12, and a part passes between the adjacent flat tubes 12 without colliding with the flat tube 12. .

  The air flowing toward the flat tube 12 has the collar portion 17 cut by the leading edge notch portion 18, so that the air flow upstream side (−x direction) side surface of the flat tube 12 without contacting the collar portion 17. Contact directly.

  The air in contact with the air flow upstream side (−x direction) side surface of the flat tube 12 exchanges heat with the refrigerant flowing through the refrigerant flow path 13 on the air flow upstream side (−x direction) of the flat tube 12, and then adjoins the air. It passes between a plurality of matching flat tubes 12.

The air passing between the plurality of adjacent flat tubes 12 collides with the heat transfer promoting portion 15 provided in the fin 11, and heat transfer with the fin 11 is promoted.

  Next, the use of the present embodiment will be described by taking as an example the case where the heat exchanger 10 of the present embodiment is used for the outdoor unit 20 of the air conditioner.

  4 is a zx plan view showing the internal structure of the outdoor unit 20 to which the heat exchanger 10 of the present embodiment is applied, and FIG. 5 is a plan view of the outdoor unit 20 to which the heat exchanger 10 of the present embodiment is applied. It is yz front view which shows an internal structure.

  As shown in FIGS. 4 and 5, the outdoor unit 20 includes a compressor 21, a switching valve 22, an outdoor expansion valve 23, a blower 24, and the heat exchanger 10. The outdoor unit 20 and the indoor unit (not shown) are connected by a liquid pipe 25 and a gas pipe 26.

  In the heat exchanger 10, a plurality of flat tubes 12 are arranged in the horizontal direction (z direction, x direction) so that they are parallel to each other along the axial direction (y direction) of the header pipes 27a, 27b. The refrigerant flow path 13 in the flat tube 12 communicates with the header pipes 27a and 27b.

  The header pipe 27a is connected to the switching valve 22 via the refrigerant pipe 28a and to the outdoor expansion valve 23 via the refrigerant pipe 28b. In addition, a partition plate 29 is provided inside the header pipe 27a, and the refrigerant flow path is divided on the upper side (+ y direction) and the lower side (−y direction) of the header pipe 27a.

  First, when performing a cooling operation, the heat exchanger 10 functions as a condenser. The gas refrigerant sent from the compressor 21 of the outdoor unit 20 flows into the header pipe 27a from the refrigerant pipe 28a via the switching valve 22. This gas refrigerant passes through the header pipe 27a and flows into the refrigerant flow paths 13 of the plurality of flat tubes 12 connected to the upper side (+ y direction) of the header pipe 27a in the horizontal direction (+ z direction, + x Direction) and flow out to the header pipe 27b.

  The refrigerant that has flowed out of the header pipe 27b flows into the refrigerant flow paths 13 of the plurality of flat tubes 12 that are connected to the lower side in the axial direction (−y direction) of the header pipe 27b, and in the horizontal direction (−x direction, −z). Direction). In the flat tube 12, the refrigerant dissipates heat and condenses by exchanging heat with the air sent by the blower 24.

  The condensed refrigerant flows into the header pipe 27a, and flows out from the refrigerant pipe 28b through the outdoor expansion valve 23 and the liquid pipe 25 to the indoor unit.

  The condensed refrigerant that has flowed into the indoor unit absorbs heat and evaporates by exchanging heat with air in an indoor heat exchanger (not shown). The evaporated refrigerant passes through the gas pipe 26 and circulates to the compressor 21 via the switching valve 22.

  When performing the heating operation, the heat exchanger 10 functions as an evaporator. The gas refrigerant sent from the compressor 21 of the outdoor unit 20 passes through the gas valve 26 via the switching valve 22 and flows out to the indoor unit.

  The gas refrigerant that has flowed into the indoor unit radiates heat and condenses by exchanging heat with air in an indoor heat exchanger provided in the indoor unit. The condensed refrigerant passes through the liquid pipe 25 and the outdoor expansion valve 23, becomes a gas-liquid two-phase refrigerant, and flows into the header pipe 27a from the refrigerant pipe 28b.

  The gas-liquid two-phase refrigerant flows from the header pipe 27a into the refrigerant flow paths 13 of the plurality of flat tubes 12 connected to the lower side in the axial direction (−y direction) of the header pipe 27a, and is horizontally (+ z direction, + Direction) and flows out to the header pipe 27b.

  The refrigerant that has flowed out of the header pipe 27b flows into the refrigerant flow paths 13 of the plurality of flat tubes 12 connected to the upper side in the axial direction (+ y direction) of the header pipe 27b, and is horizontal (-x direction, -z direction). Flowing into. The refrigerant absorbs heat and evaporates in the flat tube 12 by exchanging heat with the air sent by the blower 24.

  The evaporated refrigerant flows into the header pipe 27a, passes through the inside, and circulates from the refrigerant pipe 28a to the compressor 21 via the switching valve 22.

  When functioning as an evaporator, a low-temperature refrigerant flows through the refrigerant flow path 13 of the flat tube 12 to exchange heat with air, and moisture in the air adheres to the surfaces of the fins 11 and the flat tube 12 and condenses. Water is generated. In particular, condensed water adheres as frost in colder areas and in colder winter conditions such as lower outdoor air conditions.

  About the heat exchanger comprised as mentioned above, at least one part of the air flow upstream (-x direction) side surface of the flat tube 12 stops contacting the fin 11, and the air flow upstream (-x direction) of the flat tube 12 ) When air is interposed between the side surface and the fin 11, heat transfer from the side of the air flow upstream (−x direction) of the flat tube 12 to the front edge of the fin 11 becomes dull.

  Therefore, since it is possible to suppress the occurrence of frost on the fin 11 on the upstream side (−x direction) of the air flow with a large amount of humidity in the air even in conditions where frost formation is more likely to occur, such as in cold regions and severe winter seasons, A decrease in the amount of air passing through the heat exchanger 10 due to an increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

  In addition, since at least a part of the collar portion 17 of the fin 11 is cut and the air is in direct contact with the air flow upstream side (−x direction) side surface of the flat tube 12, the air flow upstream side (−x direction) of the flat tube 12. ) Can be promoted and the heat exchanger performance can be further improved.

(Embodiment 2)
6 is a fin plan view of the xy plane of the heat exchanger according to Embodiment 2 of the present invention, and FIG. 7 is an enlarged fin view of the xy plane of the heat exchanger according to Embodiment 2 of the present invention. FIG. 7 is an enlarged view B of FIG.

As shown in FIGS. 6 and 7, when the opening width of the leading edge notch 18 on the flat tube 12 side is h and the height of the flat tube 12 in the y direction is H, h <H It is what.
Thereby, the height in the y direction of the flat tube 12 becomes larger than the opening of the front edge notch 18 on the flat tube 12 side, and when the flat tube 12 is inserted, the flat tube 12 becomes flat of the front edge notch 18. It will contact and be fixed at the opening on the tube 12 side.

  Accordingly, since each flat tube 12 can be inserted by a predetermined amount, during the low outside air heating operation, due to variations in the insertion amount of the flat tube 12, the temperature locally decreases at the front edge portion of the fin 11 and frost formation occurs. Generation | occurrence | production can be suppressed, the fall of the air quantity which passes the heat exchanger 10 by the increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

  Further, h is preferably at least 0.1 mm. Thereby, when brazing and joining the fin 11 and the flat tube 12, it can suppress that a brazing material flows into the front edge notch part 18 by a capillary phenomenon, and the front edge notch part 18 is filled with a brazing material.

  Furthermore, h is preferably larger. As a result, the collar portion 17 of the fin 11 on the air flow upstream side (−x direction) of the flat tube 12 is largely cut, and the area in direct contact with the air flow upstream side (−x direction) of the flat tube 12 increases. Further, heat transfer from the air flow upstream side (−x direction) side surface of the flat tube 12 to the front edge portion of the fin 11 is promoted while promoting heat transfer on the air flow upstream side (−x direction) of the flat tube 12. Decrease in the amount of air passing through the heat exchanger 10 due to an increase in ventilation resistance, which can further suppress the occurrence of frost formation on the fin 11 on the upstream side (−x direction) of the air flow that becomes dull and has a high humidity amount in the air. Is suppressed, and the heat exchange performance can be improved.

  Further, the position where the center plane a passing through the central portion of the height of the flat tube 12 in the y direction and parallel to the air flow direction (x direction) intersects with the front edge portion of the fin 11 is a point C. Assuming that the leading edge is point D and the leading edge notch 18 is the most upstream air flow direction (−x direction) is point E, point E is downstream of the air flow from the intermediate position between point C and point D. It is preferable to provide at the position (+ x direction).

  Thereby, since the distance from the front edge part of the fin 11 to the front edge notch part 18 can be ensured, when inserting the flat tube 12 in the fin 11, the intensity | strength of the fin 11 can be ensured, and the fin 11 is torn or broken. Can be prevented.

  The distance from the point E to the point D is preferably at least 0.1 mm. Thereby, when brazing and joining the fin 11 and the flat tube 12, it can suppress that a brazing material flows into the front edge notch part 18 by a capillary phenomenon, and the front edge notch part 18 is filled with a brazing material.

  8 is a fin plan view of the xy plane of the heat exchanger according to the first modification of the second embodiment of the present invention, and FIG. 9 is an x of the heat exchanger according to the second modification of the second embodiment of the present invention. FIG. 10 is a fin plan view of the xy plane of the heat exchanger in the third modification of the second embodiment of the present invention, and FIG. 11 is a fourth modification of the second embodiment of the present invention. FIG. 12 is a fin plan view of an xy plane of a heat exchanger in a fifth modification of the second embodiment of the present invention, and FIG. 13 is an embodiment of the present invention. It is a fin top view of the xy plane of the heat exchanger in the modification 6 of the form 2.

  As shown in FIG. 8, the leading edge notch 18 passes through the central portion of the flat tube 12 in the height in the y direction, and is based on the center plane a parallel to the air flow direction (x direction). It goes without saying that the same effect can be obtained even if the position is shifted in the direction).

  Further, the front edge notch 18 may be a triangle or a rectangle as shown in FIGS. Thereby, the cutting area of the leading edge notch 18 is increased, the amount of air interposed between the air flow upstream side (−x direction) side surface of the flat tube 12 and the fin 11 is increased, and the air flow of the flat tube 12 is increased. Since heat transfer from the upstream side (−x direction) side surface to the front edge of the fin 11 is further blunted, frost formation at the fin 11 on the upstream side (−x direction) of the air flow with a large amount of humidity in the air Generation | occurrence | production can further be suppressed, the fall of the air quantity which passes the heat exchanger 10 by increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

  Moreover, as shown in FIG. 11, FIG. 12, the front edge notch part 18 may incline in the gravity direction (-y direction) with respect to the air flow direction (+ x direction).

  Thereby, since the condensed water that has flowed into the leading edge notch 18 flows in the direction of gravity (−y direction), it can be quickly drained from the leading edge notch 18, and the residual dew condensation can be suppressed. A decrease in the amount of air passing through the heat exchanger 10 due to the increase can be prevented, and the heat exchange performance can be improved.

  Also, a plurality of front edge notches 18 may be provided for one flat tube 12, as shown in FIG.

  As a result, the number of cut portions of the fin 11 increases, and heat transfer to the front edge of the fin 11 becomes dull. Therefore, the arrival at the fin 11 on the upstream side (−x direction) of the air flow having a large amount of humidity in the air. Generation | occurrence | production of frost can further be suppressed, the fall of the air quantity which passes the heat exchanger 10 by increase in ventilation resistance is suppressed, and heat exchange performance can be improved.

(Embodiment 3)
FIG. 14 is a fin plan view of the xy plane of the heat exchanger according to Embodiment 3 of the present invention.

  As shown in FIG. 14, the front edge notch 18 is provided with a drainage notch 19 including a gravity direction (−y direction) component.

  Thereby, the condensed water generated on the upstream side of the air flow (−x direction) of the flat tube 12 and flowing into the leading edge notch 18 flows through the drain notch 19 and flows in the gravity direction (−y direction). However, the amount of water increases and the gravity applied to the condensed water increases, so that the water quickly flows down.

  Therefore, even during high-load operation where the amount of condensed water generated is large, it is possible to suppress the remaining of dew condensation water, to prevent a reduction in the amount of air passing through the heat exchanger 10 due to an increase in ventilation resistance, and heat exchange The performance can be improved.

  Further, since the condensed water flows down quickly without freezing during the low outside air temperature heating operation, it is possible to prevent the heat exchanger 10 from freezing and stop the heating operation, thereby improving the heating capacity.

  Further, the drainage notch 19 makes the heat transfer from the air flow upstream side (−x direction) side surface of the flat tube 12 to the front edge portion of the fin 11 dull, so that even under conditions where frost formation is more likely to occur, air The generation of frost on the fin 11 on the upstream side (−x direction) of the air flow with a large amount of humidity can be suppressed, and the decrease in the amount of air passing through the heat exchanger 10 due to the increase in the ventilation resistance is suppressed. Exchange performance can be improved.

  The opening width w of the drainage notch 19 is preferably at least 0.1 mm. Thereby, when brazing and joining the fin 11 and the flat tube 12, it can suppress that a brazing material flows into the drainage notch part 19 by a capillary phenomenon, and the front edge notch part 19 is filled with a brazing material.

  Further, a position where the center plane b passing through the center portion of the adjacent flat tubes 12 and parallel to the air flow direction (x direction) intersects with the front edge portion of the fin 11 is a point F, a center plane a, and a point F The angle formed by the line connecting point D and point D is θ, the lowest point in the gravity direction (−y direction) of the drainage notch 19 is point G, the center plane a, and the center plane a to point G is the shortest When the position where the line connected by the distance intersects is a point H, it is preferable that GH ≧ tan θ × DH.

  Thereby, in the front edge part of the fin 11, between the front edge part (point D) of the flat tube 12 and the shortest distance (point C) from the flat tube 12, and the front edge part (point D) of the flat tube 12 ) To the farthest distance (point F) from the flat tube 12, a portion where the fin 11 is cut occurs, and heat transfer from the flat tube 12 to the front edge of the fin 11 becomes dull. The entire front edge of the fin 11 on the upstream side (−x direction) of the air flow having a large amount of humidity in the air can further suppress the formation of frost, and the air passing through the heat exchanger 10 due to an increase in ventilation resistance A decrease in the amount is suppressed, and the heat exchange performance can be improved.

  FIG. 15 is a fin plan view of the xy plane of the heat exchanger in the first modification of the third embodiment of the present invention.

  As shown in FIG. 15, the drainage notch 19 is formed so as to extend only in the direction of gravity (−y direction).

  As a result, the condensed water generated on the upstream side of the air flow (−x direction) of the flat tube 12 and flowing into the leading edge notch portion 18 travels through the drainage notch portion 19 and more smoothly in the direction of gravity (−y direction). It grows and grows, the amount of water increases, and the gravity on the condensed water increases, so that it flows down quickly.

  Therefore, even at the time of maximum load operation where the amount of condensed water generated is further increased, residual dew condensation water can be suppressed, and a decrease in the amount of air passing through the heat exchanger 10 due to an increase in ventilation resistance can be prevented. Exchange performance can be improved.

  Moreover, since the distance from the front edge part of the fin 11 to the drainage notch part 19 can be ensured, when inserting the flat tube 12 in the fin 11, the intensity | strength of the fin 11 can be ensured and the tear and breakage of the fin 11 are suppressed. be able to.

  FIG. 16 is a fin plan view of the xy plane of the heat exchanger in the second modification of the third embodiment of the present invention.

As shown in FIG. 16, the drainage notch 19 may be formed not on the air flow upstream side (−x direction) of the leading edge notch 18 but on the air flow upstream side (−x direction) of the flat tube 12. .
Thereby, since the distance from the front edge part of the fin 11 to the drainage notch part 19 can be further secured, when the flat tube 12 is inserted into the fin 11, the strength of the fin 11 can be further secured, and the fin 11 is broken or broken. Can be prevented.

  Further, since the drainage notch 19 is formed at the lower end in the gravity direction (−y direction) of the leading edge notch 18, the number of places where the condensed water in the leading edge notch 18 is retained is reduced, and the condensed water is more quickly supplied. It is possible to drain water, prevent a decrease in the amount of air passing through the heat exchanger 10 due to an increase in ventilation resistance, and improve heat exchange performance.

  In the heat exchanger using a flat tube, the present invention reduces the fin efficiency on the upstream side of the air flow and suppresses frost formation on the upstream side of the air flow of the fin, while suppressing heat transfer on the upstream side of the air flow of the flat tube. It is a heat exchanger that can improve heat exchange performance by promoting it, and can be applied to uses such as a refrigerator, an air conditioner, and a hot water supply / air-conditioning combined device.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Fin 3 Tube insertion notch part 4 Refrigerant flow path 5 Flat tube 6 Flat part 10 Heat exchanger 11 Fin 12 Flat tube 13 Refrigerant flow path 14 Flat part 15 Heat transfer promotion part 16 Pipe insertion notch part 17 Color part 18 Front edge notch 19 Drain notch 20 Outdoor unit 21 Compressor 22 Switching valve 23 Outdoor expansion valve 24 Blower 25 Liquid pipe 26 Gas pipe 27a, 27b Header pipe 28a, 28b Refrigerant piping 29 Partition plate

Claims (3)

  In the heat exchanger configured with a plurality of plate-like fins arranged at a predetermined interval and a plurality of flat tubes provided with a plurality of refrigerant flow paths, the fin includes a flat portion and a downstream of the air flow The flat tube inserted into the tube insertion notch, comprising a tube insertion notch formed in parallel to each other for inserting the flat tube on the side, and a collar portion for contacting the flat tube A front edge notch is provided in the flat part from at least a part of the air flow upstream side of the heat exchanger.   2. The heat exchanger according to claim 1, wherein h <H, where h is a flat tube side opening width of the leading edge notch and H is a height of the flat tube. The heat exchanger according to claim 2, wherein a drainage cutout portion including a gravity direction component is provided in the front edge cutout portion.