JPH1114276A - Cross fin heat exchanger - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To further improve the heat exchange capacity of a cross fin heat exchanger provided with fins composed of waffle fins and slit fins. SOLUTION: A rear edge 3b of a waffle fin 3 arranged on the upstream side in the air flow direction and a front edge 4a of a slit fin 4 arranged on the downstream side in the air flow direction are all or part of the edge direction. In the configuration divided in the area,
At least in the portion where the rear edge 3b of the waffle fin 3 is separated from the front edge 4a of the slit fin 4, a flat portion extending substantially parallel to the air flow direction is provided on the rear edge 3b of the waffle fin 3. A flat surface portion 8 is provided.
With this configuration, the air flow flowing from the waffle fin 3 side to the slit fin 4 side is made to flow substantially parallel to the air flow direction on the flat surface portion 8, and smoothly flows to the front edge 4 a side of the slit fin 4 as it is. Inflow,
The shape resistance on the side of the slit fins 4 is reduced as much as possible, the heat transfer performance is also improved, and the heat exchange capacity is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross fin heat exchanger.

[0002]

2. Description of the Related Art Conventionally, in a cross fin heat exchanger in an air conditioner, particularly in a cross fin heat exchanger which becomes an outdoor unit during a heating operation, a front edge portion of the fin is quickly frosted during a heating operation due to a fin structure. Is caused to cause a clogging state. As a result, there is a problem that the defrost operation interval is shortened and the heating characteristic is accordingly deteriorated. As one means for solving such a problem, for example, JP-A-2-71096
As disclosed in Japanese Unexamined Patent Publication, as the fins, waffle fins having a relatively low heat transfer performance and slit fins having a relatively high heat transfer performance are used in combination, and the waffle fins are disposed on the upstream side in the air flow direction. There has been proposed a technique in which fins are arranged on the downstream side in the air flow direction to suppress frost formation on the waffle fins located on the fin leading edge side.

[0003]

However, when the fins are composed of waffle fins and slit fins arranged before and after in the direction of air flow, for example, the fins are used in the form of a straight plate. (Ie,
There is no problem when the cross fin heat exchanger has the appearance of a rectangular thick plate, but when the fin is used as an “L” -shaped or “U” -shaped bent plate-like shape (ie, , Cross fin heat exchanger is “L” shaped or “U”
As described below, there is a problem that the ventilation resistance of the fins increases and the heat exchange capacity of the heat exchanger decreases.

That is, as shown in FIG. 18A, a fin 31 composed of a combination of a waffle fin 32 and a slit fin 33 is placed in a state where the waffle fin 32 is located on the upstream side in the air flow direction. For example, FIG.
In the case of bending and using an “L” shape as shown in FIG. 18 or a “C” shape as shown in FIG. 18C, the waffle fins 32 located on the outer side in the bending direction and the slit fins 33 located on the inner side in the bending direction Because the required length is different between and
It is not possible to form a structure in which both are integrally connected in the entire region, and it is necessary to separate the waffle fins 32 and the slit fins 33 in the entire region or a part thereof.

FIGS. 19 and 20 show a flat substrate 35.
Are alternately bent in the plate thickness direction to connect a plurality of inclined surfaces 36, 36,... Having different inclination directions in the air flow direction, and heat transfer tubes 34A, 34A,. Waffle fins 32 and flat substrate 37
Are formed in the middle part of the penetrating portion of the heat transfer tubes 34B, 34B,... And slits 38, 38,. 33, the waffle fins 32 are located on the upstream side in the air flow direction,
Is disposed so as to be located downstream in the direction of air flow, and has a fin 31 configured such that a rear edge 32b of the waffle fin 32 and a front edge 33a of the slit fin 33 are closely opposed to each other. The exchanger 30 is shown.

However, in the cross-fin heat exchanger 30 having such a configuration, as shown in FIG. 21, the most downstream inclined surface portion 36 of the waffle fin 32 located on the upstream side and the above-mentioned inclined surface portion 36 located on the downstream side. Since the front edge 33a of the slit fin 33 has a predetermined intersection angle, the air flow flowing from the waffle fin 32 side to the slit fin 33 side is, as shown by a wind speed distribution line in FIG.
It flows into the slit fin 33 side from an oblique direction. As a result, on the slit fin 33 side, the shape resistance increases due to the oblique inflow of the air flow, and the heat transfer performance decreases, whereby the heat exchange capacity of the cross fin heat exchanger 30 decreases. Things.

Accordingly, the present invention provides a cross fin heat exchanger including a fin composed of a waffle fin located on the upstream side in the air flow direction and a slit fin located on the downstream side. As a result, the cross-fin heat exchanger as a whole has a high heat exchange capacity by reducing the heat transfer performance as much as possible, while also increasing the effective heat transfer area of the fins and optimizing the fin pitch. The purpose is to further improve the heat exchange capacity by improving the drainage of the fins.

[0008]

Means for Solving the Problems In the present invention, the following configuration is adopted as specific means for solving such problems.

(1) In the first invention of the present application, as illustrated in FIGS. 1, 4, 5, 7, 9, 11, and 13, the thickness of the flat substrate 6 is increased. Waffle fins 3 which are alternately bent to both sides in the direction and are provided with heat exchangers 5A, 5A,.
, And slits 10, 10,... Formed by cutting and raising a part of the substrate 9 on the plate-shaped substrate 9, and the heat transfer tubes 5B, 5B,. And the slit fins 4 are arranged before and after in the air flow direction such that the waffle fins 3 are located on the upstream side in the air flow direction and the slit fins 4 are located on the downstream side, respectively. In the cross-fin heat exchanger in which the rear edge 3b of the slit fin 4 and the front edge 4a of the slit fin 4 are divided in the entire or partial area in the edge direction, at least the rear edge 3b of the waffle fin 3 and the slit fin 4 A flat surface portion 8 extending substantially parallel to the air flow direction is provided at the rear edge 3b of the waffle fin 3 in a portion separated from the front edge 4a of the waffle fin 3. There.

(2) In the second invention of the present application, as illustrated in FIG. 2, in the cross fin heat exchanger according to the first invention, the above-mentioned waffle fin 3 provided at the rear edge 3b is provided. Flat surface portion 8 and slit fin 4
Is positioned at substantially the same position in the fin plate thickness direction.

(3) In the third invention of the present application, as illustrated in FIG. 4, in the cross fin heat exchanger according to the first invention, the above-mentioned waffle fin 3 provided at the rear edge 3b is provided. Flat surface portion 8 and slit fin 4
Is deviated in the thickness direction of the fin plate.

(4) In the fourth invention of the present application, as exemplified in FIGS. 5, 7 and 9, respectively,
Alternatively, in the cross fin heat exchanger according to the third invention, the width of the waffle fins 3 in the air flow direction is set to be larger than the width of the slit fins 4 in the air flow direction, and 3 is characterized in that the heat transfer tube 5A is displaced downstream from the center position of the waffle fin 3 in the width direction.

(5) In the fifth invention of the present application, as illustrated in FIG. 7, in the cross fin heat exchanger according to the fourth invention, the heat transfer tube 5B attached to the slit fin 4 is The slit fins 4 are characterized in that the slit fins 4 are arranged so as to be deviated upstream from the center position in the air flow direction.

(6) In the sixth invention of the present application, as illustrated in FIG. 9, in the cross fin heat exchanger according to the fourth invention, the heat transfer tube 5B attached to the slit fin 4 is The slit fins 4 are characterized in that the slit fins 4 are arranged so as to be deviated downstream from the center position in the air flow direction.

(7) In the seventh invention of the present application, as exemplified in FIGS. 11 and 3, the cross-fin heat according to the first, second, third, fourth, fifth or sixth invention is used. In the exchanger, the heat transfer tubes 5 in the waffle fins 3
A, a flat mounting seat 12 is provided at the penetrating portion of the mounting seat 12, and the upper end 12 a and the lower end 12 b of the mounting seat 12
2 is characterized in that it has a square shape that expands at an acute angle toward the center.

(8) In the eighth invention of the present application, as illustrated in FIG. 11, in the cross fin heat exchanger according to the seventh invention, the front edge 3 of the waffle fin 3 is provided.
a, extending from the mounting seat 12 to the front edge 3a in the direction of air flow, and having a width gradually decreasing from the mounting seat 12 toward the front edge 3a. A flat surface portion 13 having a trapezoidal planar shape is provided.

(9) According to a ninth aspect of the present invention, as shown in FIG. 13, in the cross fin heat exchanger according to the seventh aspect, the front edge 3 of the waffle fin 3 is provided.
a, extending from the mounting seat 12 to the front edge 3a in the direction of air flow, the width dimension being substantially the same from the mounting seat 12 to the front edge 3a. A flat surface portion 13 having a substantially rectangular planar shape is provided.

(10) In the tenth invention of the present application, FIG.
As illustrated in FIGS. 5 to 17, respectively, in the cross fin heat exchanger according to the first, second, third, fourth, fifth, sixth, seventh, eighth, or ninth invention, The slits 10, 10,... Are arranged in multiple rows in the slit fin 4 before and after in the air flow direction.
, 0, 10,... Has a discontinuous structure extending in a direction substantially perpendicular to the air flow direction and having cut-and-raised portions 10a and split portions 10b alternately arranged in the direction. The slit 10 is characterized in that the dividing portion 10b of one slit 10 and the dividing portion 10b of the other slit 10 are not continuous in the air flow direction.

[0019]

According to the present invention, the following effects can be obtained by adopting such a configuration.

(A) The cross fin heat exchanger according to the first invention of the present application is arranged on the rear edge 3b of the waffle fin 3 arranged on the upstream side in the air flow direction and on the downstream side in the air flow direction. In a configuration in which the front edge 4a of the slit fin 4 is divided in the entire or partial region in the edge direction, at least the rear edge 3b of the waffle fin 3 and the front edge 4a of the slit fin 4 are divided. In the above-mentioned portion, a flat flat surface portion 8 extending substantially parallel to the air flow direction is provided at the rear edge 3b of the waffle fin 3.

Therefore, when the airflow flows from the waffle fin 3 side to the slit fin 4 side, the airflow flows on the waffle fin 3 side because the flat surface portion 8 is provided at the rear edge 3b of the waffle fin 3. The air flow flows in a wavy shape along each of the inclined surfaces 7, 7,... Of the waffle fins 3, and then becomes a flow substantially parallel to the air flow direction on the flat surface 8. Then, the airflow having a flow substantially parallel to the airflow direction flows into the front edge 4a of the slit fin 4, which is located downstream of the flat surface portion 8 and has a plane substantially parallel to the airflow direction. Thus, the inflow of the air flow on the side of the slit fins 4 becomes smooth, the shape resistance on the side of the slit fins 4 is reduced as much as possible, and the heat transfer performance is also improved. As a result, the cross fin heat exchanger This is to improve the heat exchange performance as a whole.

That is, according to the cross fin heat exchanger of the present invention, the wavy flow peculiar to the waffle fin 3 is substantially parallel to the air flow direction at the flat surface portion 8 provided on the rear edge 3b of the waffle fin 3. By deflecting into a natural flow,
A problem peculiar to the fin 2 formed by combining the waffle fin 3 and the slit fin 4 arranged in a divided state downstream of the waffle fin 3 (that is, an increase in shape resistance due to an oblique flow of air flow into the slit fin 4) Etc.) to secure high heat exchange performance.

(B) According to the cross-fin heat exchanger according to the second aspect of the present invention, the following specific effects can be obtained in addition to the effects described in (a) above. That is, in the present invention, the flat surface portion 8 provided at the rear edge 3b of the waffle fin 3 and the front edge 4 of the slit fin 4
a is located at substantially the same position in the fin plate thickness direction, so that air flows from the flat surface portion 8 located at the rear edge 3 b of the waffle fin 3 to the front edge 4 a side of the slit fin 4. Is smoother, ventilation resistance is further reduced, and further improvement in heat exchange capacity can be expected.

(C) As in the cross-fin heat exchanger according to the third aspect of the present invention, the following specific effects can be obtained in addition to the effects described in (a) above. That is, in the present invention, the flat surface portion 8 provided at the rear edge 3b of the waffle fin 3 and the front edge 4 of the slit fin 4
a is displaced in the thickness direction of the fin plate, so that the flat surface portion 8 of the waffle fin 3 and the slit fin 4
And the discontinuity becomes significant. As a result, the boundary layer on the surface of the waffle fins 3 is separated from the boundary layer on the surface of the slit fins 4. For example, the boundary layer on the waffle fin 3 side and the boundary layer on the slit fin 4 side are continuous. The boundary layer is reliably prevented from developing synergistically, and the heat transfer performance of the fins 2 is improved accordingly, which in turn promotes the improvement of the heat exchange capacity of the cross fin heat exchanger.

(D) According to the cross-fin heat exchanger according to the fourth invention of the present application, the following specific effects are obtained in addition to the effects described in (a), (b) or (c) above. Can be played. That is, in the present invention, the waffle fins 3
Is set to be larger than the width of the slit fins 4 in the air flow direction, and in the waffle fins 3, the heat transfer tube 5 </ b> A is moved from the center of the waffle fins 3 in the width direction. Are also displaced to the downstream side, so that the width of the waffle fins 3 is increased and the heat transfer tubes 5
A decrease in heat transfer performance due to the arrangement on the downstream side of A promotes reduction and uniformization of the amount of frost on the fin surface, thereby reducing ventilation resistance and extending the defrost operation interval, while reducing the heat transfer performance. Is compensated by an increase in the effective heat transfer area due to the reduction of the dead water area due to the downstream arrangement of the heat transfer tubes 5A. As a result, a high heat exchange capacity can be obtained, and in an air conditioner using the cross fin heat exchanger, improvement in heating performance is promoted.

(E) According to the cross-fin heat exchanger according to the fifth aspect of the present invention, the following specific effects can be obtained in addition to the effects described in the above (d). That is, in the present invention, the heat transfer tubes 5B attached to the slit fins 4 are arranged so as to be deflected upstream from the center position of the slit fins 4 in the air flow direction. The heat transfer tube 5A on the side of the slit fin 4 is shifted to the downstream side from the center in the width direction of the waffle fin 3 in the air flow direction.
Of the slit fins 4 on the upstream side of the center position in the air flow direction, the heat transfer tubes 5A located on the upstream side in the air flow direction and the heat transfer tubes 5B located on the downstream side in the air flow direction Is reduced in the air flow direction, and the passage area between the heat transfer tubes 5A and 5B is reduced. As a result, each of these heat transfer tubes 5A,
The airflow flowing through the space between the fins 5B has a higher flow velocity as the passage area is reduced, and the heat transfer performance in the fin 2 is improved accordingly.

(F) According to the cross-fin heat exchanger according to the sixth aspect of the present invention, the following specific effects can be obtained in addition to the effects described in the above (d). That is, in the present invention, the heat transfer tubes 5B attached to the slit fins 4 are arranged so as to be deviated downstream from the center position of the slit fins 4 in the air flow direction. On the side, the heat transfer tube 5B
The dead water area on the downstream side of the slit fins is reduced, the effective heat transfer area in the slit fins 4 is increased accordingly, and the heat exchange capacity can be further improved.

(G) According to the cross fin heat exchanger according to the seventh invention of the present application, the above (a), (b), (c),
The following specific effects can be obtained in addition to the effects described in (d), (e) or (f). That is, in the present invention, a flat mounting seat 12 is provided at a portion of the waffle fin 3 that penetrates the heat transfer tube 5A, and the upper end 12a and the lower end 12b of the mounting seat 12 are connected to the center of the mounting seat 12. , The water droplets formed on the surface of the waffle fin 3 above the mounting seat 12 on the upper side of the mounting seat 12 are prevented from forming water droplets on the surface of the mounting seat 12.
When it reaches the upper end portion 12a of the mounting seat 12, it is guided by the ridge line of the upper end portion 12a having a square shape that expands at an acute angle, and flows downward more smoothly. The heat exchange performance of the cross fin heat exchanger can be further improved by improving the heat transfer performance.

(H) According to the cross-fin heat exchanger according to the eighth aspect of the present invention, the following specific effects can be obtained in addition to the effects described in (G) above. That is, in the present invention, between the front edge 3a of the waffle fin 3 and the mounting seat 12, the front edge 3a is continuous with the mounting seat 12.
To the mounting seat 12
From the front edge 3a to the front edge 3a, the flat surface portion 13 having a substantially trapezoidal planar shape whose width dimension gradually decreases is provided, so that the flat surface portion 13 functions as a reinforcing rib of the waffle fin 3 and the waffle fin 3 3 above heat transfer tube 5A
The bending stiffness of the more upstream portion is increased, and the fin pitch in the cross fin heat exchanger is appropriately maintained, so that a high heat exchange capacity can be secured.

Further, since the flat surface portion 13 exhibits a function of guiding an air flow, the air flow is guided by the flat surface portion 13 and easily wraps around the heat transfer tube 5A.
The dead water area generated behind the heat transfer tube 5A is reduced as much as possible, and the heat transfer performance of the waffle fins 3 is further improved.

(I) According to the cross-fin heat exchanger according to the ninth aspect of the present invention, the following specific effects can be obtained in addition to the effects described in (G) above. That is, in the present invention, between the front edge 3a of the waffle fin 3 and the mounting seat 12, the front edge 3a is continuous with the mounting seat 12.
To the mounting seat 12
From the front edge 3a to the front edge 3a, a flat surface portion 13 having a substantially rectangular planar shape whose width is substantially the same is provided.
The flat surface portion 13 functions as a rib for reinforcing the waffle fins 3, and the bending stiffness of the portion of the waffle fins 3 upstream of the heat transfer tube 5A is increased, so that the fin pitch in the cross fin heat exchanger is properly maintained. High heat exchange capacity can be secured.

Further, since the flat surface portion 13 exhibits the function of guiding the air flow, the air flow is guided by the flat surface portion 13 and easily wraps around the heat transfer tube 5A.
The dead water area generated behind the heat transfer tube 5A is reduced as much as possible, and the heat transfer performance of the waffle fins 3 is further improved.

(V) According to the cross-fin heat exchanger according to the tenth aspect of the present invention, (a), (b),
In addition to the effects described in (c), (d), (e), (f), (g), (h) or (li), the following specific effects can be obtained. That is, in the present invention, the slit fin 4
The slits 10, 10,... Are arranged in multiple rows before and after in the air flow direction, while the slits 10, 10,.
Is a discontinuous structure extending in a direction substantially perpendicular to the air flow direction and having cut-and-raised portions 10a and dividing portions 10b alternately arranged in the direction, and slits 10, 10 which are arranged back and forth in the air flow direction. Since the dividing portion 10b of one slit 10 and the dividing portion 10b of the other slit 10 are not continuous in the air flow direction, the rigidity of the slit fins 4 is relatively low. The cut-and-raised portion 10a and the dividing portion 10b having relatively high rigidity are alternately present in both the air flow direction and the direction perpendicular thereto. Therefore, for example, as in the case where the cut-and-raised portions 10a having low rigidity are made continuous in the air flow direction, the cut-and-raised portions 1a are formed.
0a, 10a,... Does not cause a local decrease in rigidity, and the slit fins 4 have a high rigidity despite having a configuration provided with the slits 10, 10,. As a result, the fin pitch in the cross fin heat exchanger is properly maintained, and higher heat exchange performance is obtained.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cross fin heat exchanger according to the present invention will be specifically described below based on several embodiments.

First Embodiment (see FIGS. 1 to 3) FIGS. 1 and 2 show a main part of a cross-fin heat exchanger 1 according to a first embodiment of the present invention. This cross fin heat exchanger 1 is used, for example, as a heat exchanger for an outdoor unit of an air conditioner, and includes a fin 2 formed by combining a waffle fin 3 and a slit fin 4 described below having different configurations. , A plurality of the waffle fins 3, 3,.
A plurality of heat transfer tubes 5A, 5A,... Are arranged at a predetermined pitch in the longitudinal direction of the waffle fins 3 in a state where the heat transfer tubes 5A, 5A,. A plurality of heat transfer tubes 5B, 5B,... Are passed through the slit fins 4, 4,. Are arranged at a predetermined pitch in the longitudinal direction.

The waffle fins 3 are formed by bending a substantially flat substrate 6 alternately in the thickness direction thereof so that a plurality of inclined surfaces 7, 7,... Are directed from the front edge 3a to the rear edge 3b. In this embodiment, a flat surface portion 8 extending substantially parallel to the plate surface direction of the waffle fin 3 is further provided on the rear edge 3b in this embodiment. It is provided continuously to the trailing edge of the inclined surface portion 7, 7,.

The slit fins 4 are provided on a flat substrate 9.
Are provided with a plurality of slits 10, 10,... Formed by cutting and raising a part of the substrate 9. The slits 10, 10,... Are provided in the substrate 9 at intermediate portions of the heat transfer tubes 5B, 5B,.
B,... Are arranged in multiple rows in the width direction of the slit fins 4.

The fins 2 are configured by arranging the waffle fins 3 on the upstream side in the air flow direction and the slit fins 4 on the downstream side in the air flow direction. In this case, as shown in FIG. 3, the rear edge 3b of the waffle fin 3 and the front edge 4a of the slit fin 4 are opposed to each other in the air flow direction, and are orthogonal to the air flow direction. In, the positions are relatively set so as to be located on substantially the same straight line.

In the cross fin heat exchanger 1 thus configured, the air flow is caused to flow from the front edge 3a of the waffle fin 3 to the rear edge 4b of the slit fin 4 so that the air flow is reduced. And each of the heat transfer tubes 5A, 5A,.
-Heat exchange is performed with the refrigerant circulating in the same 5B.

In this case, in the cross-fin heat exchanger 1, the waffle fins 3 having relatively low heat transfer performance are arranged on the upstream side of the air flow, and the slits having relatively high heat transfer performance are provided on the downstream side. By disposing the fins 4, the heat transfer performance of the fins 2 is set such that the leading edge thereof is lower than the trailing edge, and the leading edge portion of the fin 2 during the heating operation, that is, the waffle fin 3 portion Frost formation is suppressed as much as possible, and the heating performance is improved by extending the defrost operation interval.

On the other hand, the fin 2
Is constituted by the waffle fins 3 and the slit fins 4 and the waffle fins 3 are arranged on the front edge side of the slit fins 4, the air flow from the waffle fins 3 side causes the front edge 4 a of the slit fins 4 a As described above, it flows into the side from an oblique direction, the shape resistance of the slit fins 4 increases, and the ventilation resistance increases accordingly, and the heat transfer performance may decrease. However, in this embodiment, as described above, since the flat surface portion 8 extending substantially parallel to the air flow direction is provided at the rear edge 3b of the waffle fin 3, the slit is formed from the waffle fin 3 side. The air flow blown out to the fin 4 side is formed by the inclined surfaces 7, 7,.
What has been made into a wavy curved flow by is deflected in the flat surface portion 8 in a direction substantially parallel to the air flow direction,
In this deflected state, the slit fin 4 on the downstream side thereof
Into the side from a direction substantially parallel to the plane direction of the slit fins 4. As a result, the slit fins 4
Is reduced as much as possible, the ventilation resistance and the heat transfer performance are improved, and the heat exchange capacity of the cross-fin heat exchanger 1 is enhanced.

Second Embodiment (See FIG . 4) FIG. 4 shows a main part of a cross fin heat exchanger 1 according to a second embodiment of the present invention. The cross fin heat exchanger 1 of this embodiment has the same basic configuration as the cross fin heat exchanger 1 of the first embodiment, and differs from the first embodiment in that As shown in FIG. 4, the rear edge 3b of the waffle fin 3 located on the upstream side in the air flow direction and the front edge 4a of the slit fin 4 located on the downstream side in the air flow direction are aligned in the air flow direction. The point is that it is deviated by about 1/3 of the fin pitch in the orthogonal direction.

In the cross-fin heat exchanger 1 configured as described above, the same operation and effect as those of the cross-fin heat exchanger 1 in the first embodiment can be obtained, and in addition, the waffle fin 3 and the slit The following specific effects can be obtained based on the offset configuration with the fins 4. That is, like the cross fin heat exchanger 1 of this embodiment, when the rear edge 3b of the waffle fin 3 and the front edge 4a of the slit fin 4 are displaced in a direction orthogonal to the air flow direction, the waffle Since the continuity between the boundary layer on the surface side of the fins 3 and the boundary layer on the surface side of the slit fins 4 is interrupted, the boundary layer on the waffle fin 3 side is used, for example, when these are not deviated. And the boundary layer on the side of the slit fins 4 is continuously prevented from developing synergistically, so that the heat transfer performance in each of the fins 3 and 4 is improved, Therefore, the heat exchange capacity of the cross fin heat exchanger 1 is further improved.

Third Embodiment (See FIGS. 5 and 6) FIGS. 5 and 6 show a cross-fin heat exchanger 1 according to a third embodiment of the present invention. The cross fin heat exchanger 1 of this embodiment includes heat transfer tubes 5A, 5A,..., And is upstream in the air flow direction, like the cross fin heat exchangers 1 according to the first and second embodiments. Waffle fins 3 arranged on the side and heat transfer tubes 5B, 5B,.
And the slit fins 4 arranged on the downstream side in the air flow direction to form the fins 2, and a flat surface portion 8 extending substantially parallel to the air flow direction is provided at the rear edge 3 b of the waffle fins 3. The difference from the above embodiments is that the width of the waffle fins 3 is set to be relatively larger than the width of the slit fins 4 and the width of the waffle fins 3 This is the point where the arrangement positions of the heat transfer tubes 5A, 5A,... Are shifted to the downstream side from the center position in the width direction of the waffle fins 3.

With this configuration, on the waffle fin 3 side, the width is increased and the heat transfer tubes 5
The reduction in the heat transfer performance due to the arrangement on the downstream side of A promotes the reduction and uniformization of the amount of frost on the fin surface, thereby reducing the ventilation resistance and extending the defrost operation interval. In addition, the heat transfer performance of the waffle fins 3 is reduced by disposing the heat transfer tube 5A downstream of the center of the width of the waffle fins 3 so that the dead water area in the waffle fins 3 is reduced and the waffle fins 3 are reduced in size. This is compensated for by an increase in the effective heat transfer area of the fin 3.

As a result, in the cross-fin heat exchanger 1 of this embodiment, a high heat exchange capacity is obtained, and in the air conditioner provided with the cross-fin heat exchanger 1, the heating performance is further improved. Improvement can be expected.

Fourth Embodiment (See FIGS. 7 and 8) FIGS. 7 and 8 show a main part of a cross-fin heat exchanger 1 according to a fourth embodiment of the present invention. The cross fin heat exchanger 1 according to this embodiment is based on the configuration of the cross fin heat exchanger 1 according to the third embodiment. In this basic configuration, each of the transmissions further provided on the slit fin 4 side is used. This is a point where the arrangement positions of the heat tubes 5B, 5B,... Are shifted to the front edge 4a side from the center position in the width direction of the slit fins 4.

With this configuration, the heat transfer tubes 5A, 5A,... On the waffle fin 3 side are displaced downstream from the center in the width direction of the waffle fin 3 in the air flow direction. Heat transfer tubes 5B, 5 on slit fin 4 side
The heat transfer tubes 5A, 5B,... Positioned upstream in the air flow direction have a synergistic effect that B,... Are deflected upstream from the center position of the slit fins 4 in the air flow direction.
5A,... And the heat transfer tubes 5B, 5B,
The distance between the heat transfer tubes 5A, 5A,..., 5B, 5B,.
The passage area between them is reduced.

As a result, each of these heat transfer tubes 5A, 5A,.
The air flow flowing between the heat transfer tubes 5B, 5B,... Has a higher flow velocity as the passage area is reduced, and the heat transfer performance in the fins 2 is improved accordingly.

Fifth Embodiment (see FIGS. 9 and 10) FIGS. 9 and 10 show a cross-fin heat exchanger 1 according to a fifth embodiment of the present invention. The cross-fin heat exchanger 1 of this embodiment is to be referred to as a modification of the cross-fin heat exchanger 1 of the fourth embodiment, and the cross-fin heat exchanger 1 of the fourth embodiment.
Is different from the cross fin heat exchanger 1 of the fourth embodiment in that the heat transfer tubes 5B, 5B,... While it was located upstream,
Conversely, the cross fin heat exchanger 1 of this embodiment is arranged such that the heat transfer tubes 5B, 5B,... Are arranged downstream of the center of the slit fins 4 in the width direction.

With such a configuration, on the slit fin 4 side, each of the heat transfer tubes 5B, 5B,... The dead water area on the downstream side of the heat pipes 5B, 5B,... Is reduced. As a result, the effective heat transfer area of the slit fins 4 is increased, and the heat exchange capacity of the cross fin heat exchanger 1 is further improved.

Sixth Embodiment (Refer to FIGS. 11 and 12) FIGS. 11 and 12 show a main part of a cross fin heat exchanger 1 according to a sixth embodiment of the present invention, specifically, the cross fin heat exchanger 1. 2 shows a waffle fin 3 which is one of the components of the fin 2 provided in the fin heat exchanger 1. Note that components other than the waffle fins 3 (for example, the slit fins 4 and the like) are the same as those in the above-described embodiments, and thus are not illustrated.

The heat transfer tubes 5A, 5A,... Are attached to the waffle fins 3 in a state penetrating the waffle fins in the thickness direction. In this case, in this embodiment,
A mounting seat 12 having a flat surface is provided around a fin collar 14 provided at a mounting portion of the heat transfer tubes 5A. The upper end portion 12a and the lower end portion 12b of the mounting seat 12 have an angular shape that gradually expands at an acute angle α toward the center of the mounting seat 12. Further, a front edge 12c of the waffle fin 3 is attached to the front end 12c of the mounting seat 12 from the front end 12c.
a flat surface portion 13 having a trapezoidal flat shape whose width dimension gradually decreases from the front end portion 12c side toward the front edge 3a side is formed. In this case, the width dimension of the flat surface portion 13 near the front end portion 12c is set substantially equal to the diameter of the heat transfer tube 5B.

When the waffle fins 3 are configured as described above, the following useful effects can be obtained.

First, by forming both the upper end portion 12a and the lower end portion 12b of the mounting seat 12 in a square shape, dew condensation on the surface of the waffle fin 3 above the mounting seat 12 due to dew condensation occurs. When the water droplets flow down the surface to the mounting seat 12 side and reach the upper end 12a of the mounting seat 12, the water droplets are guided by the ridge line of the angular upper end 12a, which expands at an acute angle, and smoothly moves downward. As a result, the drainage of the waffle fins 3 is improved, and the heat transfer performance of the waffle fins 3 is expected to further improve the heat exchange capacity of the cross fin heat exchanger 1.

Second, by providing the flat surface portion 13 between the front edge 3a of the waffle fin 3 and the front end portion 12c of the mounting seat 12, the flat surface portion 13 reinforces the waffle fin 3. Function of the waffle fins 3 and the bending stiffness of the portion of the waffle fins 3 on the upstream side of the heat transfer tube 5A is increased, so that the fin pitch in the cross fin heat exchanger 1 is appropriately maintained to ensure high heat exchange capacity. Becomes possible.

Third, the flat surface portion 13 functions to guide airflow, and the flat surface portion 13
The width of the air flow is increased toward the mounting seat 12, so that the airflow flowing into the waffle fins 3 is guided by the flat surface portion 13 and easily wraps around the heat transfer tube 5A. As a result, the dead water area generated in the area behind the heat transfer tube 5A is reduced as much as possible, and the effective heat transfer area of the waffle fins 3 is increased accordingly, and the heat transfer performance is further improved.

Seventh Embodiment (see FIGS. 13 and 14) FIGS. 13 and 14 show the main parts of a cross fin heat exchanger 1 according to a seventh embodiment of the present invention, specifically, the cross fin heat exchanger 1. 2 shows a waffle fin 3 which is one of the components of the fin 2 provided in the fin heat exchanger 1. Note that components other than the waffle fins 3 (for example, the slit fins 4 and the like) are the same as those in the above-described embodiments, and thus are not illustrated.

The waffle fin 3 of this embodiment can be said to be a modification of the waffle fin 3 of the sixth embodiment, and is different from the waffle fin 3 in that the flat surface portion 13 extends over the entire length thereof. The point is that they are formed to have substantially the same width dimension.

With this configuration, in addition to the same effect as the cross fin heat exchanger 1 in the third embodiment, the width of the flat surface 13 is smaller than that of the flat fin 13 in the sixth embodiment. By being larger than that, the amount of air guided to the back side of the heat transfer tube 5A is increased, and the dead water area on the back side of the heat transfer tube 5B is further reduced, so that the heat transfer performance can be further improved. In addition, since the reinforcing effect of the waffle fins 3 by the flat surface portion 13 is large, it is possible to more reliably secure an appropriate fin pitch.

Eighth Embodiment (see FIGS. 15 to 17) FIGS. 15 to 17 show structural examples of the slit fin 4 in the cross fin heat exchanger 1 according to the eighth embodiment of the present invention. ing. The slit fins 4 in this embodiment do not constitute the slits 10, 10,. In the embodiment, two or three) cut and raised portions 10a,
10a and a dividing portion 10b located therebetween, and each slit 10,
, The dividing portion 10b in one slit 10 and the dividing portion 10 in the other slit 10
b is not continuous in the air flow direction (in other words, is not located on the same straight line in the air flow direction).
This is where the formation position is set.

FIGS. 15 to 17 show examples of the arrangement of the slits 10 having the above-described configuration, and there is almost no difference in the operation and effect.

When the slits 10, 10,... Having the above-described configuration are arranged in multiple rows in the air flow direction, the rigidity of the slit fins 4 is relatively low. The cut-and-raised portions 10a and the divided portions 10b having relatively high rigidity are alternately present in both the air flow direction and the direction perpendicular thereto. Therefore, for example, as in the case where the cut-and-raised portions 10a having low rigidity are made continuous in the air flow direction,
a, 10a,..., the rigidity does not locally decrease at the continuous portion,
Are the above-mentioned slits 10 and 1 which contribute to the reduction in rigidity.
It has high rigidity in spite of the configuration having 0,. As a result, in the cross fin heat exchanger 1, a higher heat exchange capacity can be obtained by appropriately maintaining the fin pitch.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a cross fin heat exchanger according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is an enlarged view of a part viewed from the arrow III in FIG. 2;

FIG. 4 is a sectional view of a main part of a cross fin heat exchanger according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of a cross fin heat exchanger according to a third embodiment of the present invention.

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a cross-sectional view of a cross fin heat exchanger according to a fourth embodiment of the present invention.

8 is a sectional view taken along line VIII-VIII of FIG.

FIG. 9 is a cross-sectional view of a cross fin heat exchanger according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a sectional view of a waffle fin portion in a cross fin heat exchanger according to a sixth embodiment of the present invention.

FIG. 12 is a sectional view taken along the line XII-XII of FIG. 11;

FIG. 13 is a sectional view of a waffle fin portion in a cross fin heat exchanger according to a seventh embodiment of the present invention.

FIG. 14 is a sectional view taken along line XIV-XIV of FIG.

FIG. 15 is a sectional view showing a first structural example of a slit fin portion in a cross fin heat exchanger according to an eighth embodiment of the present invention.

FIG. 16 is a sectional view showing a second structure example of a slit fin portion in a cross fin heat exchanger according to an eighth embodiment of the present invention.

FIG. 17 is a cross-sectional view showing a third structural example of a slit fin portion in a cross fin heat exchanger according to an eighth embodiment of the present invention.

FIG. 18 is an explanatory diagram of a fin forming state in a heat exchanger including a waffle fin and a slit fin.

FIG. 19 is a cross-sectional view of a conventional cross-fin heat exchanger.

20 is a sectional view taken along the line XX-XX of FIG.

FIG. 21 is an enlarged view of a portion taken along arrow XXI of FIG. 20;

[Explanation of symbols]

1 is a cross fin heat exchanger, 2 is a fin, 3 is a waffle fin, 4 is a slit fin, 5A and 5B are heat transfer tubes,
6 is a substrate, 7 is an inclined surface portion, 8 is a flat surface portion, 9 is a substrate, 1
0 is a slit, 10a is a cut-and-raised portion of the slit, 10b is a split portion of the slit, 12 is a mounting seat, 13 is a flat surface portion, 14
Is a fin collar.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Isao Fujinami 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries Inside the Kanaoka Plant of Sakai Seisakusho Co., Ltd. Sakai Plant Kanaoka Factory

Claims (10)

[Claims] The heat exchangers (5A), (5A),... Are formed by alternately bending a flat substrate (6) to both sides in the thickness direction and penetrating in the thickness direction. Waffle fins (3) attached, slits (10) formed by cutting and raising a part of substrate (9) on flat substrate (9),
(10), and a slit fin (4) penetrating in the plate thickness direction and having heat transfer tubes (5B), (5B),. The slit fins (4) are arranged before and after in the air flow direction so as to be located on the upstream side in the air flow direction and on the downstream side, respectively, and the rear edge (3b) of the waffle fin (3) and the slit Leading edge (4a) of fin (4)
And a cross-fin heat exchanger obtained by dividing the waffle fin (3) at least in a rear region (3b) of the waffle fin (3).
In the part where the front edge (4a) of the slit fin (4) is separated from the rear edge (3b) of the waffle fin (3), a flat flat surface portion extending substantially parallel to the air flow direction. (8) A cross-fin heat exchanger characterized by the provision of (8). 2. The slit fin (4) according to claim 1, wherein the flat surface portion (8) provided at a rear edge (3b) of the waffle fin (3).
Characterized in that the front edge (4a) of the cross fin is located at substantially the same position in the fin plate thickness direction. 3. The slit fin (4) according to claim 1, wherein the flat surface portion (8) provided at a rear edge (3b) of the waffle fin (3).
A cross-fin heat exchanger characterized in that the front edge (4a) is displaced in the fin plate thickness direction. 4. The width of the waffle fin (3) in the air flow direction is set to be larger than the width of the slit fin (4) in the air flow direction. In the waffle fin (3), the heat transfer tube (5
A) The cross fin heat exchanger wherein A) is displaced downstream from the center position in the width direction of the waffle fins (3). 5. The heat transfer tube (5B) attached to the slit fin (4) is deflected upstream from a center position of the slit fin (4) in the air flow direction. A cross-fin heat exchanger characterized by being arranged. 6. The heat exchanger according to claim 4, wherein the heat transfer tube (5B) attached to the slit fin (4) is displaced downstream from a center position of the slit fin (4) in the air flow direction. A cross-fin heat exchanger characterized by being arranged. 7. The heat transfer tube (5A) according to claim 1, 2, 3, 4, 5, or 6, wherein the heat transfer tube (5A) in the waffle fin (3).
A flat mounting seat (12) is provided in the penetrating portion of the mounting seat (12), while an upper end (12a) and a lower end (12) of the mounting seat (12) are provided.
b) is a square shape that expands at an acute angle toward the center of the mounting seat (12). 8. The front edge (3a) of the waffle fin (3) between the front edge (3a) of the waffle fin (3) and the mounting seat (12), continuously to the mounting seat (12). ), And a flat surface portion (13) having a substantially trapezoidal planar shape whose width dimension gradually decreases from the mounting seat (12) toward the front edge (3a) is provided. A cross fin heat exchanger. 9. The front edge (3a) between the front edge (3a) of the waffle fin (3) and the mounting seat (12), continuously to the mounting seat (12). ) And a flat surface portion (13) having a substantially rectangular planar shape whose width dimension is substantially the same from the mounting seat (12) to the front edge (3a). A cross-fin heat exchanger characterized in that: 10. The method according to claim 1,2,3,4,5,6,7,
In 8 or 9, while the slits 10, 10, ... in the slit fin 4 are arranged in multiple rows before and after in the air flow direction, the slits (10), (10), ... A slit (10a) extending in a direction substantially perpendicular to the air flow direction and having a cut-and-raised portion (10a) and a split portion (10b) arranged alternately in the direction, and a slit ( 10), (1
Between 0), the dividing portion (10b) in one slit (10) and the dividing portion (10b) in the other slit (10) are configured not to be continuous in the air flow direction. Cross fin heat exchanger.