JPH1062086A - Heat exchanger - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the heat exchange efficiency of a heat exchanger in which a plurality of plate-like fins and a plurality of stages of heat exchange tubes are contacted and crossed to improve the drainage of dew condensation water. SOLUTION: A plurality of plate-like fins 1 arranged at appropriate intervals, and insertion holes 2 provided in these plate-like fins 1 are provided.
In the heat exchanger provided with a plurality of heat exchange tubes 3 penetrating through, a gap 5 for flowing water is formed between at least the lower surface of the heat exchange tubes 3 and the insertion holes 2. This allows the dew water remaining between the plate-like fins 1 to flow in the longitudinal direction of the heat exchange tube 3 through the gap 5, thereby increasing the number of water droplets of the dew water that has flowed and falling downward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger, and more particularly, to a heat exchanger used for, for example, an evaporator for a car or an air conditioner for a house, which is arranged at appropriate intervals. The present invention relates to an improvement of a heat exchanger in which a plurality of plate-like fins and a plurality of stages of heat exchange tubes are contacted and crossed.

[0002]

2. Description of the Related Art Conventionally, as this type of heat exchanger, as shown in FIG. 11, a plurality of plate-like fins a arranged in parallel at regular intervals, and these plate-like fins a are bored. A heat exchanger having a heat exchange tube b having a circular cross section penetrating an insertion hole c having a circular cross section is known. In this heat exchanger, after inserting a circular heat exchange tube b into an insertion hole c formed in a plate-like fin a, a cylindrical rod having a diameter slightly larger than the inner diameter of the circular heat exchange tube b is inserted into the heat exchange tube. The plate-shaped fin a and the circular heat exchange tube b are brought into close contact with each other.

As another heat exchanger, as shown in FIG. 12, there is known a heat exchanger having a heat exchange tube d having a flat cross section instead of the circular heat exchange tube b. In this heat exchanger, a flat heat exchange tube d is inserted into an insertion hole e having a substantially flat elliptical cross section formed in a plate fin a and the plate fin a is inserted.
And the flat heat exchange tube d are brought into close contact with each other, and then integrated by brazing or the like. By using the heat exchange tube d having a flat cross section as described above, there is an advantage that a loss of air resistance can be reduced as compared with a circular heat exchange tube.

[0004]

However, in this type of conventional heat exchanger, as shown in FIGS. 13A and 13B, the heat exchange tubes b and d and the insertion holes c and e are formed. Due to the close contact, for example, in a heat exchanger used as an evaporator, if the drainage of the plate-like fins a is poor, as shown in FIG. 14, the dew condensation water f stays between the plate-like fins a. As a result, there is a problem that the ventilation resistance increases, the air volume decreases, and the capacity is reduced. Also,
In a heat exchanger used for an outdoor unit such as a heat pump or a room air conditioner, during the winter heating operation, there is a possibility that the dew condensation water f staying between the plate-like fins a freezes. The amount of heat of fusion increased, causing a delay in the defrosting time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a heat exchanger capable of improving the heat exchange efficiency by improving the drainage of dew condensation water remaining between plate-like fins. It is assumed that.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a plurality of plate-like fins arranged at appropriate intervals and insertion holes provided in these plate-like fins are provided. In a heat exchanger including a plurality of heat exchange tubes penetrating therethrough, a gap for flowing water is formed between at least a lower surface of the heat exchange tubes and the insertion hole.

In the present invention, the number and shape of the gap may be arbitrary as long as the gap is provided between at least the lower surface of the heat exchange tube and the insertion hole. It may be formed by a notch provided on the opening edge of the insertion hole (Claim 2), or may be formed by a concave portion provided on the heat exchange tube (Claim 3).

According to a fourth aspect of the present invention, there are provided a plurality of plate-like fins arranged at appropriate intervals, and a plurality of flat heat exchange tubes penetrating through insertion holes provided in these plate-like fins. In the heat exchanger, a gap for flowing water is formed between at least a lower surface of the heat exchange tube and the insertion hole at an end of the flat heat exchange tube in a cross-sectional direction. . In this case, the gap may be formed at least at one end in the cross-sectional direction of the flat heat exchange tube. The gap may be provided at both ends of the flat heat exchange tube and at an intermediate portion thereof (claim 5).

According to a sixth aspect of the present invention, there are provided a plurality of plate-like fins arranged at appropriate intervals and a plurality of flat heat exchange tubes penetrating through insertion holes provided in these plate-like fins. In the heat exchanger, the flat heat exchange tube is inclined in a cross-sectional direction of the heat exchange tube, and a water flow between at least a lower surface of the lower end of the flat heat exchange tube and the insertion hole. It is characterized by forming a gap.

According to the seventh aspect of the present invention, there are provided a plurality of plate-like fins arranged at appropriate intervals, and a plurality of heat exchange tubes penetrating through insertion holes provided in these plate-like fins. In the heat exchanger, a flux is partially applied to the heat exchange tube, and the heat exchange tube and the plate-like fins are brazed through the flux, so that the heat exchange tube and the insertion hole are interposed. It is characterized by forming a gap for flowing water.

According to the first aspect of the present invention, a gap for flowing water is formed between at least the lower surface of the heat exchange tube and the insertion hole formed in the plate-like fin, so that the space between the plate-like fins is formed. The dew water remaining in the condensate water can flow in the longitudinal direction of the heat exchange tube through the gap, increasing the volume of the water droplets of the dew water that has flowed, and increasing the gravity acting on the water droplets. Can be dropped downward beyond the restraining force due to the capillary action that occurs in the device. Therefore, the ventilation resistance between the plate-like fins can be reduced, and
The air volume can be increased, and the heat exchange efficiency can be improved. Further, in the heat exchanger used as the outdoor unit of the heat pump / room air conditioner, the dew condensation staying between the plate-shaped fins during the heating operation in winter can drop downward as described above, so that the dew condensation can be frozen. Can be suppressed, the amount of heat of fusion of freezing of the dew condensation can be reduced, and the defrosting time can be shortened.

According to the fourth aspect of the present invention, a gap for water flow is formed between at least the lower surface of the heat exchange tube and the insertion hole at the end of the flat heat exchange tube in the cross-sectional direction. The dew water remaining between the plate-like fins can be caused to flow in the longitudinal direction of the heat exchange tube through the gap formed at the end of the flat heat exchange tube, and the water droplets of the dew water flowing as described above Can be dropped down by increasing the volume. Therefore, the drainage of the heat exchanger using the flat heat exchange tubes can be improved, and the heat exchange efficiency can be improved.

According to the fifth aspect of the present invention, the gaps are provided at both ends of the flat heat exchange tube and at an intermediate portion thereof, so that the drainage and heat of the heat exchanger using the flat heat exchange tube are provided. The exchange efficiency can be further improved.

According to the sixth aspect of the present invention, the flat heat exchange tube is inclined in the cross-sectional direction of the heat exchange tube, and at least the lower end of the flat heat exchange tube at the lower side end and the insertion hole are provided between the lower surface and the insertion hole. By forming a gap for water flow in the
Condensation water remaining between the plate-shaped fins and the flat heat exchange tube can be discharged to the lower side of the flat heat exchange tube,
Since it is possible to flow in the longitudinal direction of the flat heat exchange tube through a gap on the lower side of the flat heat exchange tube, it is possible to increase the volume of water droplets of the condensed water that has flown in a short period of time and drop it down. Can be. Therefore, the drainage and heat exchange efficiency of the heat exchanger using the flat heat exchange tubes can be further improved.

According to the present invention, the flux is partially applied to the heat exchange tube, and the heat exchange tube and the plate-like fins are brazed through the flux to form the heat exchange tube. Since a gap for flowing water can be formed between the hole and the insertion hole, a gap for flowing water can be formed without providing a notch in the plate-like fin or providing a concave portion in the heat exchange tube. be able to. Therefore, the manufacture of the heat exchanger becomes easy, and the cost can be reduced.

[0016]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

First Embodiment FIG. 1 is a schematic perspective view showing a first embodiment of a heat exchanger according to the present invention, FIG. 2 is a front view (a) showing a main part thereof, and FIG.
It is an expanded sectional view (b) along an A line.

The heat exchanger has a plurality of plate-like fins 1 arranged at appropriate intervals and a plurality of parallel cross sections penetrating through circular insertion holes 2 formed in these plate-like fins 1. The heat exchanger tube 3 having a circular shape and a pair of headers, which are arranged at a distance from each other and are formed of pipes (not shown) communicating with the heat exchanger tube 3, are integrally brazed, or the heat exchanger tube 3 is expanded. It becomes. Note that one header is provided with an inlet for the heat medium, and the other header is provided with an outlet.

In the heat exchanger configured as described above, the header and the heat exchange tube 3 are formed of an extruded aluminum alloy material, and the plate-like fins 1 are formed of an aluminum alloy plate material.

In this case, for example, a V-shaped notch 4 is provided at the opening edge of the insertion hole 2 facing the lower surface of each heat exchange tube 3, and the heat exchange tube 3 and the insertion hole 2 are formed by the notch 4. A gap 5 for flowing water is formed between the first and second gaps. The gap 5 is set to a size that is not closed by the brazing material during brazing, and is set to a size that does not affect the heat conduction between the plate-like fin 1 and the heat exchange tube 3.

As described above, by providing the gap 5 between the lower surface of each heat exchange tube 3 and the insertion hole 2,
The dew condensation water 50 staying in between can flow in the longitudinal direction of the heat exchange tube 3. Therefore, the flowing dew water 50 tends to be united by the action of the surface tension, and flows through the gap 5, and the water droplets of the dew water 50 increase. As a result, the gravitational force applied to the water droplets 6 increases, easily exceeding the binding force due to the capillary phenomenon generated between the plate-like fin 1 and the dew condensation water 50, the water droplets of the dew condensation water 50 easily drop downward, and the drainage property becomes poor. (See FIG. 2B).

Second Embodiment FIG. 3 is a schematic perspective view showing a heat exchanger according to a second embodiment of the present invention, and FIG. 4 is a front view (a) showing a main part thereof and FIG.
It is an expanded sectional view (b) along line B.

In the second embodiment, a flat heat exchange tube 10 made of an aluminum alloy is used in place of the circular heat exchange tube 3 in the heat exchanger of the first embodiment.

That is, the heat exchanger of the second embodiment comprises a plurality of plate-like fins 1 arranged at appropriate intervals and a substantially flat elliptical insertion hole 2 formed in these plate-like fins 1.
0 and a pair of headers each composed of a pipe (not shown) that is arranged at an interval from each other and has a plurality of pipes (not shown) that are parallel to each other and have a substantially flat elliptical cross section and that are in communication with the flat heat exchange pipe 1. Are brazed together. In this case, for example, a flat U-shaped notch 6 is provided at the opening edge of the insertion hole 20 facing the lower surface of each heat exchange tube 10,
The notch 6 forms a gap 5 for flowing water between the heat exchange tube 10 and the insertion hole 20. A plurality of passages 12 defined by a plurality of reinforcing walls 11 are formed in the flat heat exchange tube 10 at appropriate intervals. Also,
On the upper side of the insertion hole 20, there is provided a standing piece 21 that is bent substantially at a right angle to the plate-like fin 1.
Have a positioning function of contacting the adjacent plate-like fins 1 to maintain a constant interval between the plate-like fins 1 and to improve the adhesion to the flat heat exchange tube 10.

By providing the gap 5 between the lower surface of each heat exchange tube 10 and the insertion hole 20 as described above,
As shown in (b), the dew water 50 staying between the plate-like fins 1 can flow in the longitudinal direction of the heat exchange tube 3, and the water droplets of the dew water 50 can be increased. As a result,
As in the first embodiment, the gravity applied to the water droplet 6 increases, and the water droplet of the dew condensation water 50 easily falls downward beyond the binding force due to the capillary phenomenon generated between the plate-like fin 1 and the dew condensation water 50. And the drainage property is improved. In this case, the water droplets that have fallen downward fall on the upper surface of the lower flat heat exchange tube 10, but the water droplets that have fallen on the upper surface of the flat heat exchange tube 10 fall downward from the side of the flat heat exchange tube 10. Because it falls
There is no danger that water droplets will stay and form dew.

In the above description, the gap 5 for flowing water is formed by the notch 6 provided in the insertion hole 20. As shown in FIGS. 5 and 6, the lower surface side of the flat heat exchange tube 10 is formed. The gaps 5 may be formed by the concave ridges 13 provided in the ridges. The gap 5 is not limited to these forms, and may be formed by two notches 6 provided in the insertion hole 20 as shown in, for example, FIG. As shown in b), a gap 5 is formed between the lower surface of the flat heat exchange tube 10 and the insertion hole 20 at the end (here, both ends) in the cross-sectional direction of the flat heat exchange tube 10. You may. In addition, the gaps 5 may be formed at three positions, that is, both ends of the flat heat exchange tube 10 and an intermediate portion thereof (see FIG. 7C). Further, as shown in FIG. 7 (d), a flat heat exchange tube inserted into one insertion hole 20 is formed by two divided flat heat exchange tubes 10a and 10b, and the flat heat exchange tube is formed. A gap 5 may be formed between the outer ends of the exchange tubes 10a and 10b in the cross-sectional direction and the flat heat exchange tubes 10a and 10b. In this case, as shown in FIG. 7 (e), the insertion hole 20 is formed in a substantially eyeglass shape, and the two flat heat exchange tubes 10a, 10b are formed by the slit 7 at the center.
A gap 5 may be formed between them.

As described above, whether a plurality of gaps 5 are provided,
Alternatively, by providing the flat heat exchange tubes 10 at both ends in the cross-sectional direction, the space between the plate-like fins 1 and the flat heat exchange tubes 10
The dew water 50 remaining in the flat heat exchange tube 10 can flow quickly in the longitudinal direction of the flat heat exchange tube 10, so that the drainage of the heat exchanger using the flat heat exchange tube 10 can be improved.

Third Embodiment FIG. 8 is a front view showing a main part of a third embodiment of the heat exchanger according to the present invention.

In the third embodiment, an insertion hole formed in the plate-like fin 1 is formed by a tapered insertion hole 30, and a heat exchange tube is fitted into a narrow tapered portion 31 of the tapered insertion hole 30. In this case, the gap 5 is formed between the tapered heat exchange pipe 10A and the expanded tapered portion 32 of the tapered insertion hole 30.

In this case, after the tapered heat exchange tube 10A is inserted into the tapered insertion hole 30 on the side of the expanding tapered portion 32, the plate-like fin 1 and the tapered heat exchange tube 10A are relatively moved. After the tapered heat exchange tube 10A is brought into close contact with the narrow tapered portion 31 of the tapered insertion hole 30, it can be integrated by brazing or the like, so that the assembling work of the heat exchanger can be facilitated. In addition, since the upper surface of the tapered heat exchange tube 10A is inclined, the dew condensation water remaining on the tapered heat exchange tube 10A can be easily dropped downward. In addition, as shown by a two-dot chain line in FIG. 8, the gap 5 may be formed on the narrow tapered portion 31 side of the tapered insertion hole 30, or the notch 6 may be provided on the lower side of the tapered insertion hole 30. The gap 5 may be formed. By providing a plurality of gaps 5 in this way, the drainage of the heat exchanger can be further improved. In the third embodiment, the other parts are the same as those in the first and second embodiments, and thus the same parts are denoted by the same reference numerals and description thereof will be omitted.

Fourth Embodiment FIG. 9 is a front view showing a main part of a fourth embodiment of the heat exchanger according to the present invention.

In the fourth embodiment, when the heat exchange tube is formed of a flat heat exchange tube, the dew water remaining in the heat exchange tube is positively discharged. That is, the insertion hole is formed by a substantially flat elliptical insertion hole 40 (inclined insertion hole) inclined in the cross-sectional direction, and the heat exchange tube is formed by the inclined insertion hole 40.
Heat exchange tube 10B inclined in the cross-sectional direction to penetrate through
(Inclined heat exchange tube)
This is a case where a gap 5 is formed at least between the lower surface and the inclined insertion hole 40 at the end on the lower side of the inclination of B.

As described above, the flat heat exchange tube is inclined to form the gap 5 between at least the lower surface and the inclined insertion hole 40 at the lower end of the inclined heat exchange tube 10B. 1 and the dew condensation water 50 staying in the inclined heat exchange tube 10B can be positively caused to flow downward, and can be caused to flow in the longitudinal direction of the inclined heat exchange tube 10B through the gap 5, so that dew condensation can be achieved. Water droplets of the water 50 can be quickly increased and dropped. In the fourth embodiment, other parts are the same as those in the first and second embodiments, and therefore, the same parts are denoted by the same reference numerals and description thereof will be omitted.

Fifth Embodiment FIG. 10 is a perspective view of a heat exchange tube according to a fifth embodiment of the present invention (a) and a cross-sectional view of a main part of the heat exchange tube and plate-like fins brazed (b). It is.

In the fifth embodiment, a gap for flowing water is formed without providing a notch in the plate-like fin 2 and without providing a concave portion in the heat exchange tube. That is, as shown in FIG. 10A, the flux 50 is placed at the center of the upper and lower sides of the heat exchange tube, for example, the flat heat exchange tube 10.
Is applied, and the flat heat exchange tube 10 on which the flux 50 is partially applied is inserted through the insertion holes 2 of the plurality of plate-like fins 1 arranged at appropriate intervals and brazed integrally. In this case, a gap 5 for flowing water is formed between the flat heat exchange tube 10 and the insertion hole 2.

As described above, the flux 50 is partially applied to the heat exchange tube, for example, the flat heat exchange tube 10, and the flat heat exchange tube 10 and the plate-like fin 1 are integrally brazed to obtain the flux 50. The gap 5 for flowing water can be formed in a portion where no water exists. Therefore, the notch 6 is provided in the plate-like fin 1 as in the first embodiment, or the concave strip 13 is formed in the flat heat exchange tube 10 as in the second embodiment.
Thus, the gap 5 for flowing water can be easily formed without providing the heat exchanger, thereby facilitating the manufacture of the heat exchanger and reducing the cost.

In the above description, the case where the heat exchange tube is the flat heat exchange tube 10 has been described, but the heat exchange tube may be a pipe having a circular cross section. In the fifth embodiment, other parts are the same as those in the first and second embodiments, and therefore, the same parts are denoted by the same reference numerals and description thereof will be omitted.

[0038]

As described above, according to the present invention,
The following excellent effects can be obtained.

(1) According to the first aspect of the present invention, a gap for flowing water is formed between at least the lower surface of the heat exchange tube and the insertion hole formed in the plate-like fin. The dew water remaining between the fins can flow in the longitudinal direction of the heat exchange tube through the gap, increasing the volume of the water droplets of the dew water flowing, and increasing the gravity acting on the water droplets to form dew condensation on the plate fins. It can drop downward beyond the restraining force due to the capillary phenomenon generated between water. Therefore,
The ventilation resistance between the plate-like fins can be reduced, and the air volume can be increased, so that the heat exchange efficiency can be improved. Further, in the heat exchanger used as the outdoor unit of the heat pump / room air conditioner, the dew condensation staying between the plate-shaped fins during the heating operation in winter can drop downward as described above, so that the dew condensation can be frozen. Can be suppressed, the amount of heat of fusion of freezing of the dew condensation can be reduced, and the defrosting time can be shortened.

(2) According to the fourth aspect of the present invention, a gap for flowing water is formed between at least the lower surface of the flat heat exchange tube and the insertion hole at the cross-sectional end of the heat exchange tube. By doing so, it is possible to cause the dew water remaining between the plate-shaped fins to flow in the longitudinal direction of the heat exchange tube through the gap formed at the end of the flat heat exchange tube, The volume of the water droplets can be increased and fall down. Therefore, the drainage of the heat exchanger using the flat heat exchange tubes can be improved, and the heat exchange efficiency can be improved.

(3) According to the fifth aspect of the present invention, the gap is provided at both ends of the flat heat exchange tube and at an intermediate portion thereof, thereby draining the heat exchanger using the flat heat exchange tube. Performance and heat exchange efficiency can be further improved.

(4) According to the sixth aspect of the present invention, the flat heat exchange tube is inclined in the sectional direction of the heat exchange tube, and at least the lower surface and the insertion hole at the lower end of the flat heat exchange tube are inserted. Between the plate-shaped fins and the flat heat exchange tube, the condensed water can be discharged to the lower side of the flat heat exchange tube. Since the water can flow in the longitudinal direction of the flat heat exchange tube through the gap on the lower side of the heat exchange tube, the volume of the water droplets of the condensed water that has flowed can be increased in a short time and dropped down. . Therefore, the drainage and heat exchange efficiency of the heat exchanger using the flat heat exchange tubes can be further improved.

(5) According to the seventh aspect of the invention, a gap for flowing water can be formed without providing a notch in the plate-like fin or providing a concave portion in the heat exchange tube.
The manufacture of the heat exchanger becomes easy, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a first embodiment of a heat exchanger of the present invention.

FIG. 2 is a front view (a) showing a main part of the heat exchanger of FIG. 1, and an enlarged cross-sectional view (b) thereof along the line AA.

FIG. 3 is a schematic perspective view showing a second embodiment of the heat exchanger of the present invention.

FIG. 4 is a front view (a) showing a main part of the heat exchanger of FIG. 3 and an enlarged sectional view (b) thereof along the line BB.

FIG. 5 is a main part front view showing another form of the gap in the present invention.

FIG. 6 is a perspective view of FIG. 5;

FIG. 7 is a schematic front view showing still another form of the gap in the present invention.

FIG. 8 is a front view showing a main part of a third embodiment of the heat exchanger according to the present invention.

FIG. 9 is a front view showing a main part of a fourth embodiment of the heat exchanger according to the present invention.

FIG. 10A is a perspective view of a heat exchange tube according to a fifth embodiment of the present invention, and FIG. 10B is a cross-sectional view of a main part of the heat exchange tube with plate-like fins brazed.

FIG. 11 is a schematic perspective view showing a conventional heat exchanger.

FIG. 12 is a schematic perspective view showing another conventional heat exchanger.

13 is a schematic front view (a) showing a main part of the heat exchanger shown in FIG. 11, and a schematic front view (b) showing a main part of the heat exchanger shown in FIG.

FIG. 14 is an enlarged sectional view taken along lines CC and DD in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate-shaped fin 2 Insertion hole 3 Circular heat exchange tube 4 Notch 5 Gap 6 Notch 7 Slit 10 Flat heat exchange tube 10A Tapered heat exchange tube 10B Inclined heat exchange tube 13 Recessed portion 20 Insertion hole 30 Tapered insertion hole 40 Inclined insertion hole 50 Flux

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shoji Ono 1-34-1 Kambara, Kambara-cho, Anbara-gun, Shizuoka Prefecture Inside the Nippon Light Metal Co., Ltd. Group Technology Center (72) Inventor: Yasuhiko Tanaka Kambara-cho, Abara-gun, Shizuoka Prefecture Kambara 161 Nippon Light Metal Co., Ltd.Kamahara Heat Exchange Products Factory (72) Inventor Etsuro Kubota 161 Kambara Town, Kambara-cho, Anbara-gun, Shizuoka Prefecture Nippon Light Metal Co., Ltd. Machi Kambara 161 Nippon Light Metal Co., Ltd.

Claims (7)

[Claims] 1. A heat exchanger comprising: a plurality of plate-like fins arranged at appropriate intervals; and a plurality of heat exchange tubes penetrating through insertion holes provided in these plate-like fins. A heat exchanger, wherein a gap for flowing water is formed between at least the lower surface of the tube and the insertion hole. 2. The heat exchanger according to claim 1, wherein the gap is a notch provided at an opening edge of an insertion hole of the plate-like fin. 3. The heat exchanger according to claim 1, wherein the gap is a recess provided on the heat exchange tube.
A heat exchanger, characterized in that: 4. A heat exchanger comprising: a plurality of plate-like fins arranged at appropriate intervals; and a plurality of flat heat-exchange tubes penetrating through insertion holes provided in these plate-like fins. A heat exchanger, wherein a gap for water flow is formed between at least a lower surface of the heat exchange tube and the insertion hole at an end of the flat heat exchange tube in a cross-sectional direction. 5. The heat exchanger according to claim 4, wherein the gap is provided at both ends of the flat heat exchange tube and at an intermediate portion thereof. 6. A heat exchanger comprising: a plurality of plate-like fins arranged at appropriate intervals; and a plurality of flat heat-exchange tubes penetrating through insertion holes provided in these plate-like fins. The flat heat exchange tube is inclined in the cross-sectional direction of the heat exchange tube, and a gap for water flow is formed between at least the lower surface and the insertion hole at the lower end of the flat heat exchange tube. A heat exchanger. 7. A heat exchanger comprising: a plurality of plate-like fins arranged at appropriate intervals; and a plurality of heat exchange tubes passing through insertion holes provided in these plate-like fins. A flux is partially applied to the pipe, and the heat exchange pipe and the plate-like fins are brazed through the flux to form a gap for water flow between the heat exchange pipe and the insertion hole. A heat exchanger, comprising: