EP3550247A1

EP3550247A1 - Heat exchanger and air conditioner

Info

Publication number: EP3550247A1
Application number: EP16922957.2A
Authority: EP
Inventors: Hideaki Maeyama
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2016-12-02
Filing date: 2016-12-02
Publication date: 2019-10-09
Anticipated expiration: 2036-12-02
Also published as: JP6997722B2; WO2018100738A1; EP3550247B1; JPWO2018100738A1; EP3550247A4

Abstract

A heat exchanger with improved drainage performance is provided. In the heat exchanger, a first plate fin (12a) is spaced a first distance from at least one heat transfer tube (11) in a second direction perpendicular to a first direction. A second plate fin (12b) is spaced a second distance from the first plate fin (12a) in the second direction. The first plate fin (12a) and a first corrugated fin (13a) are connected to each other by a plurality of first connections (24) spaced a third distance from one another in the first direction. The first plate fin (12a) and a second corrugated fin (13b) are connected to each other by a plurality of second connections (25) spaced a fourth distance from one another in the first direction. The third distance and the fourth distance are greater than the first distance and the second distance.

Description

TECHNICAL FIELD

The present invention relates to heat exchangers and air conditioning apparatuses, and more particularly to a heat exchanger and an air conditioning apparatus including a corrugated fin.

BACKGROUND ART

A heat exchanger including a heat transfer tube having refrigerant flowing therethrough, and a corrugated fin connected to the heat transfer tube is conventionally known (see Japanese Patent Laying-Open No. 9-280754 , for example).

CITATION LIST

PATENT LITERATURE

PTL 1: Japanese Patent Laying-Open No. 9-280754

SUMMARY OF INVENTION

TECHNICAL PROBLEM

In the heat exchanger described above, measures are taken such as forming louvers in the corrugated fin or forming grooves in a surface of the heat transfer tube, in order to ensure drainage of condensation water formed on a surface of the corrugated fin. However, it has been difficult to ensure sufficient drainage performance at the corrugated fin only by taking such measures.
An object of the present invention is to provide a heat exchanger with improved drainage performance at a corrugated fin.

SOLUTION TO PROBLEM

A heat exchanger according to the present disclosure includes at least one heat transfer tube, a first plate fin, a second plate fin, a first corrugated fin, and a second corrugated fin. The at least one heat transfer tube extends in a first direction intersecting a direction of air flow, and has refrigerant flowing therethrough. The first plate fin extends in the first direction. The first plate fin is spaced a first distance from the at least one heat transfer tube in a second direction perpendicular to the first direction. The second plate fin extends in the first direction. The second plate fin is spaced a second distance from the first plate fin in the second direction. The first corrugated fin is disposed between the at least one heat transfer tube and the first plate fin. The second corrugated fin is disposed between the first plate fin and the second plate fin. The first plate fin and the first corrugated fin are connected to each other by a plurality of first connections spaced a third distance from one another in the first direction. The first plate fin and the second corrugated fin are connected to each other by a plurality of second connections spaced a fourth distance from one another in the first direction. The third distance and the fourth distance are greater than the first distance and the second distance.
An air conditioning apparatus according to the present disclosure includes a refrigerant circuit, the refrigerant circuit including a compressor, a first heat exchanger, an expansion valve, and a second heat exchanger, and having refrigerant circulating therethrough. At least one of the first heat exchanger and the second heat exchanger is the heat exchanger described above.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the above, the angle of inclination of an inclined portion located between the first or second connections in the first and second corrugated fins can be increased, so that the drainage of condensation water through this inclined portion can be improved.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a schematic diagram of a heat exchanger according to a first embodiment of the present invention.
Fig. 2 is a schematic partial enlarged perspective view of a region II in Fig. 1.
Fig. 3 is a schematic front view of the portion of the heat exchanger shown in Fig. 2.
Fig. 4 is a schematic partial sectional view of a heat exchanger according to a second embodiment of the present invention.
Fig. 5 is a schematic partial sectional view of a heat exchanger according to a third embodiment of the present invention.
Fig. 6 is a schematic partial perspective view of the heat exchanger shown in Fig. 5.
Fig. 7 is a schematic partial top view of the heat exchanger shown in Fig. 6.
Fig. 8 is a schematic diagram showing a refrigerant circuit of an air conditioning apparatus according to a fourth embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention are described below with reference to the drawings. The same or corresponding parts are designated by the same reference numbers in the following drawings and will not be described repeatedly. The following drawings, including Fig. 1, do not necessarily reflect the actual size relation among the components. Moreover, the forms of components represented throughout the specification are merely exemplary and are not limited to these descriptions.

First Embodiment

Fig. 1 is a schematic diagram of a heat exchanger according to a first embodiment of the present invention. Fig. 2 is a schematic partial enlarged perspective view of a region II in Fig. 1. Fig. 3 is a schematic front view of the portion of the heat exchanger shown in Fig. 2.
A heat exchanger 1 shown in Figs. 1 to 3 includes a plurality of heat transfer tubes 11 which are flat tubes, a plurality of plate fins 12 disposed between these heat transfer tubes 11, corrugated fins 13 disposed between heat transfer tubes 11 and plate fins 12 or between adjacent plate fins 12, and an upper header 2 and a lower header 3 connected respectively to the upper ends and the lower ends of heat transfer tubes 11 disposed along the direction of gravity. Heat transfer tubes 11, plate fins 12 and corrugated fins 13 form a main body portion 10. Heat transfer tube 11 is provided to extend along a first direction, which is a direction along the direction of gravity. Refrigerant flows through heat transfer tube 11. Within heat transfer tube 11 shaped as a flat tube, a plurality of refrigerant flow paths may be formed along a direction in which heat transfer tube 11 extends (first direction).
The plurality of heat transfer tubes 11 are spaced from one another in a second direction indicated by an arrow 16 and intersecting the first direction, so as to have a prescribed pitch P1 as shown in Fig. 3. In heat exchanger 1 shown in Figs. 1 to 3, first to third plate fins 12a to 12c are disposed between adjacent heat transfer tubes 11. First to fourth corrugated fins 13a to 13d are disposed between heat transfer tubes 11 and first to third plate fins 12a to 12c. The configurations between adjacent heat transfer tubes 11 are basically identical.
Stated from a different perspective, the configuration of the heat exchanger described above is such that heat exchanger 1 includes at least one heat transfer tube 11, first plate fin 12a, second plate fin 12b, third plate fin 12c, first corrugated fin 13a, second corrugated fin 13b, and third and fourth corrugated fins 13c, 13d. At least one heat transfer tube 11 extends in the first direction indicated by an arrow 15 and intersecting a direction of air flow. Refrigerant flows through heat transfer tube 11. First plate fin 12a extends in the first direction indicated by arrow 15. First plate fin 12a is spaced a first distance P21 from at least one heat transfer tube 11 in the second direction indicated by arrow 16 and perpendicular to the first direction. Second plate fin 12b extends in the first direction. Second plate fin 12b is spaced a second distance P22 from first plate fin 12a in the second direction indicated by arrow 16. A distance between second plate fin 12b and third plate fin 12c in the second direction may be equal to or different from aforementioned second distance P22. A distance between heat transfer tube 11 adjacent to third plate fin 12c and this third plate fin 12c may be equal to or different from aforementioned first distance P21. Aforementioned first distance P21 and second distance P22 may be equal to or different from each other.
First corrugated fin 13a is disposed between at least one heat transfer tube 11 and first plate fin 12a. Second corrugated fin 13b is disposed between first plate fin 12a and second plate fin 12b. Third corrugated fin 13c is disposed between second plate fin 12b and third plate fin 12c. Fourth corrugated fin 13d is disposed between third plate fin 12c and another heat transfer tube 11. First plate fin 12a and first corrugated fin 13a are connected to each other by a plurality of first connections 24 spaced a third distance P3 from one another in the first direction indicated by arrow 15. First plate fin 12a and second corrugated fin 13b are connected to each other by a plurality of second connections 25 spaced a fourth distance P4 from one another in the first direction indicated by arrow 15. First corrugated fin 13a and heat transfer tube 11 are connected to each other by a plurality of connections spaced from one another along the first direction. The distance between these connections may be equal to aforementioned third distance P3. Second corrugated fin 13b and second plate fin 12b are connected to each other by a plurality of connections spaced from one another along the first direction. The distance between these connections may be equal to aforementioned fourth distance P4. Aforementioned third distance P3 and fourth distance P4 may be equal to or different from each other.
Connections between third and fourth corrugated fins 13c, 13d, and second and third plate fins 12b, 12c and another heat transfer tube 11 are basically similar in configuration to the connections between first corrugated fin 13a, and heat transfer tube 11 and first plate fin 12a described above. Aforementioned third distance P3 and fourth distance P4 are greater than first distance P21 and second distance P22. Stated from a different perspective, the distance in the first direction between the plurality of connections where corrugated fin 13 is connected to plate fin 12 is greater than the width of space between heat transfer tube 11 and the plurality of plate fins 12 in the second direction. Louvers may be formed in inclined portions 33, 34 of first to fourth corrugated fins 13a to 13d.
In heat exchanger 1 described above, the hydrophilicity of at least a portion of the surfaces of first plate fin 12a, second plate fin 12b, third plate fin 12c, and at least one heat transfer tube 11 may be higher than the hydrophilicity of the surfaces of first corrugated fin 13a, second corrugated fin 13b, and third and fourth corrugated fins 13c, 13d. In this manner, the hydrophilicities of the surfaces of plate fin 12, corrugated fin 13, and heat transfer tube 11 can be adjusted by any method, such as changing the materials for these members, forming surface treatment layers having different hydrophilicities on these surfaces, or changing the surface roughnesses of these surfaces. For example, the surface roughness of plate fin 12 and heat transfer tube 11 may be greater than the surface roughness of corrugated fin 13. Alternatively, a hydrophilic or hydrophobic surface treatment layer may be formed either on plate fin 12 and heat transfer tube 11, or on corrugated fin 13.
In heat exchanger 1 described above, a thickness W of at least one heat transfer tube 11 may be greater than the thickness of each of first to third plate fins 12a to 12c in the second direction indicated by arrow 16 in Fig. 3. The thickness of each of first to third plate fins 12a to 12c may be greater than the thickness of each of first to fourth corrugated fins 13a to 13d.
In heat exchanger 1 described above, the plurality of first connections 24 coincide in position with the plurality of second connections 25 in the first direction indicated by arrow 15. Here, the plurality of first connections 24 coinciding in position with the plurality of second connections 25 means that each of first connections 24 at least partially overlaps with each of second connections 25 when viewed from the second direction.

In the heat exchanger according to the present disclosure, third distance P3 and fourth distance P4, which are the pitches of the plurality of connections 24, 25 where first and second corrugated fins 13a, 13b are connected to first plate fin 12a, respectively, are greater than first and second distances P21, P22, which are the widths of regions where first and second corrugated fins 13a, 13b are disposed, respectively. Moreover, as described above, the pitches of the plurality of connections where the third and fourth corrugated fins are connected to plate fin 12, respectively, are greater than aforementioned first and second distances P21, P22. Accordingly, inclined portions 33, 34 of first and second corrugated fins 13a, 13b located between these connections 24 and 25, and also the inclined portions of third and fourth corrugated fins 13c, 13d can be sufficiently inclined relative to the first direction.
For example, the angle of inclination of these inclined portions 33, 34 relative to the first direction may be 70° or less (stated from a different perspective, the angle of inclination of inclined portions 33, 34 relative to the second direction may be 20° or more). The angle of inclination of these inclined portions 33, 34 relative to the first direction may be 60° or less, 50° or less, or 45° or less. Stated from a different perspective, the angle of inclination of inclined portions 33, 34 relative to the second direction may be 30° or more, 40° or more, or 45° or more. By disposing heat exchanger 1 such that the first direction is the vertical direction, condensation water can readily flow downward at inclined portions 33, 34 of first and second corrugated fins 13a, 13b that are inclined relative to the first direction. The inclined portions of third and fourth corrugated fins 13c, 13d can similarly allow the condensation water to readily flow downward. Therefore, the drainage performance at corrugated fin 13 of heat exchanger 1 can be improved.
Moreover, in heat exchanger 1 described above, the hydrophilicity of at least a portion of the surfaces of first plate fin 12a, second plate fin 12b, and at least one heat transfer tube 11 is higher than the hydrophilicity of the surfaces of first corrugated fin 13a and second corrugated fin 13b. Accordingly, condensation water can be readily moved from the surfaces of first and second corrugated fins 13a, 13b to the surfaces of first and second plate fins 12a, 12b or the surface of heat transfer tube 11. Then, the condensation water that has moved to first and second plate fins 12a, 12b or heat transfer tube 11 can be readily moved in a vertically downward direction, for example. Accordingly, the drainage performance at the heat exchanger can be improved.
In heat exchanger 1 described above, thickness W of at least one heat transfer tube 11 is greater than the thickness of each of first and second plate fins 12a, 12b in the second direction indicated by arrow 16 in Fig. 3. The thickness of each of first and second plate fins 12a, 12b is greater than the thickness of each of first and second corrugated fins 13a, 13b. Stated from a different perspective, the thickness of each of first to third plate fins 12a to 12c is greater than the thickness of each of first to fourth corrugated fins 13a to 13d together forming corrugated fin 13. Since the thickness of plate fin 12 is greater than the thickness of corrugated fin 13 in this manner, the strength of plate fin 12 can be increased to stabilize the shape of the heat exchanger.
In heat exchanger 1 described above, the plurality of first connections 24 coincide in position with the plurality of second connections 25 in the first direction. The connections between second corrugated fin 13b and second plate fin 13b also coincide in position with the connections between third corrugated fin 13c and second plate fin 13b in the first direction, second corrugated fin 13b and third corrugated fin 13c being disposed to sandwich the plate fin therebetween. The connections between third corrugated fin 13c and third plate fin 13c also coincide in position with the connections between fourth corrugated fin 13d and third plate fin 13c in the first direction, third corrugated fin 13c and fourth corrugated fin 13d being disposed to sandwich the plate fin therebetween. As a result, the connections coincide in position at the front and rear surfaces of plate fin 12, so that the shape of plate fin 12 can be stabilized as compared to an example where these connections differ in position between the front and rear surfaces.

Second Embodiment

Fig. 4 is a schematic partial sectional view of a heat exchanger according to a second embodiment of the present invention. Fig. 4 corresponds to a schematic partial sectional view of the heat exchanger taken along a plane perpendicular to the first direction shown in Fig. 3.
The heat exchanger shown in Fig. 4 basically has a similar configuration to the heat exchanger shown in Figs. 1 to 3, but is different from the heat exchanger shown in Figs. 1 to 3 in the shapes of first to third plate fins 12a to 12c and first to fourth corrugated fins 13a to 13d. Specifically, in the direction of air flow indicated by an arrow 22, a width L2 of each of first to fourth corrugated fins 13a to 13d is greater than a width L1 of heat transfer tube 11. In addition, first to fourth corrugated fins 13a to 13d each include a portion 27 protruding more upstream in the direction of air flow than heat transfer tube 11. Moreover, in the direction of air flow, a width L3 of each of first to third plate fins 12a to 12c is greater than width L2 of each of first to fourth corrugated fins 13a to 13d. First to third plate fins 12a to 12c include portions 26 protruding more upstream in the direction of air flow than first to fourth corrugated fins 13a to 13d.
Stated from a different perspective, the configuration of the heat exchanger described above is such that, in heat exchanger 1 described above, the direction of air flow is a direction perpendicular to the first direction and the second direction, and is a direction indicated by arrow 22 in Fig. 4. In the direction of air flow, width L3 of each of first and second plate fins 12a, 12b is greater than width L2 of each of first and second corrugated fins 13a, 13b. Stated from a different perspective, width L3 of each of first to third plate fins 12a to 12c, which are a plurality of plate fins disposed between two heat transfer tubes 11, is greater than width L2 of each of first to fourth corrugated fins 13a to 13d, which are a plurality of corrugated fins disposed adjacent to these plurality of plate fins.
In heat exchanger 1 described above, portions 26 of first and second plate fins 12a, 12b protrude more upstream in the direction of air flow than first and second corrugated fins 13a, 13b. Third plate fin 12c similarly includes portion 26. That is, portions 26 of first to third plate fins 12a to 12c, which are a plurality of plate fins, protrude more upstream in the direction of air flow than first to fourth corrugated fins 13a to 13d, which are a plurality of corrugated fins. In heat exchanger 1 described above, portions 27 of first and second corrugated fins 13a, 13b protrude more upstream in the direction of air flow than at least one heat transfer tube 11. In short, portions 27 of first to fourth corrugated fins 13a to 13d, which are a plurality of corrugated fins, protrude more upstream than at least one heat transfer tube 11.
In addition, louvers 23 are formed in first to fourth corrugated fins 13a to 13d. Louvers 23 are formed in inclined portions 33, 34 (see Fig. 3) of first to fourth corrugated fins 13a to 13d. Louvers 23 are formed to extend linearly in a direction intersecting the direction of air flow, specifically a direction perpendicular to the direction of air flow. Louvers 23 are linear, but may be curved, in plan view. Louvers 23 may be formed by, for example, cutting into inclined portions 33, 34 of first to fourth corrugated fins 13a to 13d, and causing portions of inclined portions 33, 34 that are adjacent to these cuts to be inclined relative to the other portions. Alternatively, slits as simple openings may be formed instead of louvers 23.

It is assumed that heat exchanger 1 described above serves as an evaporator. In this case, low-temperature refrigerant flows through the refrigerant flow paths formed within heat transfer tube 11. Thus, heat is transferred successively through heat transfer tube 11, first corrugated fin 13a joined to heat transfer tube 11, plate fin 12a joined to first corrugated fin 13a, second corrugated fin 13b joined to plate fin 12a, and second plate fin 12b joined to second corrugated fin 13b. Since the low-temperature refrigerant is flowing through heat transfer tube 11 as described above, the surface temperature of the heat exchanger increases as the distance from heat transfer tube 11 increases.
When air is supplied to heat exchanger 1, the air passes, from the windward side of heat exchanger 1, through gaps formed by heat transfer tube 11, plate fin 12 and corrugated fin 13 of heat exchanger 1. On this occasion, the air successively exchanges heat, starting from a windward portion, and decreases in temperature. Once the air temperature decreases and reaches the dew point or lower, moisture in the air condenses and adheres to the surface of the heat exchanger as condensation water. Here, the adhesion of the condensation water starts from first to third plate fins 12a to 12c, which are farthest from heat transfer tube 11 of the heat exchanger and are of the highest temperature. Subsequently, the air temperature decreases further as the air passes through first to fourth corrugated fins 13a to 13d, causing the condensation water to adhere to first to fourth corrugated fins 13a to 13d.
Condensation water mostly adheres to a corrugated fin in a conventional heat exchanger, whereas the heat exchanger according to the present embodiment can allow most of the condensation water to adhere to first to third plate fins 12a to 12c. First to third plate fins 12a to 12c each have portion 26 protruding more windward than first to fourth corrugated fins 13a to 13d. Since there are no obstacles below these portions 26, the condensed moisture flows over the surfaces of portions 26 of first to third plate fins 12a to 12c and drops downward in a short time.
The condensation water (moisture) formed on first to fourth corrugated fins 13a to 13d, on the other hand, is directed downward by louvers 23 formed in first to fourth corrugated fins 13a to 13d, and drops downward along the shape of the corrugated fins. In a conventional corrugated fin, the inclination of a surface portion of the corrugated fin where a louver is formed relative to the first direction is relatively small, which sometimes hinders the condensation water from moving sufficiently along the corrugated fin. In contrast, in the heat exchanger according to the present embodiment, it is ensured that inclined portions 33, 34 of first to fourth corrugated fins 13a to 13d are inclined 20° or more, for example, relative to the second direction. Accordingly, the condensation water can be readily moved downward along these inclined portions 33, 34.
Heat exchanger 1 described above can produce similar effects to the heat exchanger in the first embodiment. Moreover, in heat exchanger 1 described above, width L3 of each of first to third plate fins 12a to 12c, which are a plurality of plate fins disposed between two heat transfer tubes 11, is greater than width L2 of each of first to fourth corrugated fins 13a to 13d, which are a plurality of corrugated fins disposed adjacent to these plurality of plate fins.
In this case, first to third plate fins 12a to 12c include portions 26 protruding from first to fourth corrugated fins 13a to 13d in the direction of air flow indicated by arrow 22. These protruding portions 26 extend along the first direction, and can function as a drainage path for the condensation water from first to fourth corrugated fins 13a to 13d.
In addition, the condensation water adheres early to portions 26 of first to third plate fins 12a to 12c protruding upstream in the direction of air flow. Subsequently, the condensation water can be quickly moved to the space below first and second plate fins 12a, 12b through aforementioned portions 26 of first and second plate fins 12a, 12b.

Third Embodiment

Fig. 5 is a schematic partial sectional view of a heat exchanger according to a third embodiment of the present invention. Fig. 6 is a schematic partial perspective view of the heat exchanger shown in Fig. 5. Fig. 7 is a schematic partial top view of the heat exchanger shown in Fig. 6.
The heat exchanger shown in Figs. 5 to 7 basically has a similar configuration to the heat exchanger shown in Fig. 4, but is different from the heat exchanger shown in Fig. 4 in that a plate member 14 is connected to heat transfer tube 11 on the upstream side in the direction of air flow, as well as in the disposition of louvers 23. Specifically, in the heat exchanger shown in Figs. 5 to 7, plate member 14 is disposed to be connected to an end 28 of heat transfer tube 11 on the windward side, which is the upstream side in the direction of air flow. Plate member 14 may be a hollow member or a solid member. The width of plate member 14 in the second direction (the direction indicated by arrow 16 in Fig. 3) may be equal to width W of heat transfer tube 11 (see Fig. 3). A combined width of heat transfer tube 11 and plate member 14 in the direction of air flow is equal to width L3 of each of first to third plate fins 12a to 12c. The combined width of heat transfer tube 11 and plate member 14 may be different from width L3 of each of first to third plate fins 12a to 12c, and may be equal to width L2 of each of first to fourth corrugated fins 13a to 13d, for example.
First to fourth corrugated fins 13a to 13d include inclined portions 33, 34. The plurality of louvers 23 are formed in these inclined portions 33, 34. Inclined portions 33, 34 are inclined relative to the first direction corresponding to the vertical direction. The plurality of linearly extending louvers 23 are formed in inclined portions 33, 34. The plurality of louvers 23 are formed to extend vertically downward toward the upstream side in the direction of air flow indicated by arrow 22. In short, as shown in Fig. 6, louvers 23 in inclined portions 33 are each formed to approach a protrusion vertex 36 from connection 25 toward the upstream side in the direction of air flow. Although not shown, the louvers in inclined portions 34 are each formed to approach connection 25 from protrusion vertex 36 toward the upstream side in the direction of air flow.
Stated from a different perspective, in heat exchanger 1 described above, the first direction is a direction along the direction of gravity. First corrugated fin 13a includes first inclined portions 33, 34 located between the plurality of first connections 24 (see Fig. 3) and inclined relative to the vertical direction. Second corrugated fin 13b includes second inclined portions 33, 34 located between the plurality of second connections 25 and inclined relative to the vertical direction. At least one linearly extending louver 23 is formed in at least one of first inclined portions and second inclined portions 33, 34. At least one louver 23 is formed to extend vertically downward toward the upstream side in the direction of air flow indicated by arrow 22.
Although louvers 23 are formed in all of inclined portions 33, 34 of first to fourth corrugated fins 13a to 13d, they may be formed only in some of inclined portions 33, 34. Alternatively, they may be formed in some of first to fourth corrugated fins 13a to 13d.

Heat exchanger 1 described above can produce similar effects to the heat exchanger in the second embodiment. Moreover, heat exchanger 1 described above further includes plate member 14 connected to a portion of at least one heat transfer tube 11 that is located upstream in the direction of air flow. The connection of such plate member 14 to heat transfer tube 11 can cause frost, which conventionally adheres to heat transfer tube 11, to adhere to plate member 14 in a distributed manner. Accordingly, the amount of frost formed at heat transfer tube 11 can be reduced, so that the drainage performance of heat transfer tube 11 can be improved.
In addition, since louvers 23 in the heat exchanger shown in Figs. 5 to 7 are formed to extend vertically downward toward the upstream side in the direction of air flow, the condensation water that has adhered to the surfaces of the corrugated fins can be directed through these louvers 23 to the upstream side in the direction of air flow. Since portions 26 of first to third plate fins 12a to 12c are disposed on this upstream side, these portions 26 can be utilized as drainage paths to improve the drainage performance of the heat exchanger.

Fourth Embodiment

Fig. 8 is a schematic diagram showing a refrigerant circuit of an air conditioning apparatus according to a fourth embodiment of the present invention. The refrigerant circuit shown in Fig. 8 includes a compressor 41, a first heat exchanger 42 serving as a condenser, a throttle device 43 serving as an expansion valve, a second heat exchanger 44 serving as an evaporator, and two blowers 45. Two blowers 45 are driven by blower motors 46, respectively. Two blowers 45 blow gas (for example, air) at first heat exchanger 42 and second heat exchanger 44, respectively. In the refrigerant circuit, refrigerant circulates successively through compressor 41, first heat exchanger 42, throttle device 43, and second heat exchanger 44. Stated from a different perspective, the air conditioning apparatus shown in Fig. 8 includes a refrigerant circuit, the refrigerant circuit including compressor 41, first heat exchanger 42, throttle device 43 as an expansion valve, and second heat exchanger 44, and having refrigerant circulating therethrough.
At least one of first heat exchanger 42 and second heat exchanger 44 shown in Fig. 8 is the heat exchanger described in any one of the first to third embodiments. Aforementioned blowers 45 each blow the gas at its corresponding heat exchanger along a third direction (the direction indicated by arrow 22 in Fig. 4). A four-way valve or the like may be disposed in the refrigerant circuit, to reverse the direction in which the refrigerant flows at first heat exchanger 42 and second heat exchanger 44 in the refrigerant circuit from the direction shown in Fig. 8, to thereby cause the first heat exchanger to serve as an evaporator and the second heat exchanger to serve as a condenser.

The air conditioning apparatus according to the present disclosure includes the heat exchanger according to any one of the first to third embodiments described above as its heat exchanger, and thus has sufficient drainage performance. Accordingly, lowering of efficiency or the occurrence of a fault caused by insufficient drainage of the condensation water at first and second heat exchangers 42, 44 can be suppressed.
Although the embodiments of the present invention have been described above, the embodiments described above can be modified in various ways. In addition, the scope of the present invention is not limited to the embodiments described above. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the meaning and scope equivalent to the terms of the claims.

INDUSTRIAL APPLICABILITY

The present invention is applicable to an air conditioning apparatus, a refrigeration cycle apparatus, a heat pump apparatus and the like.

REFERENCE SIGNS LIST

1 heat exchanger; 2 upper header; 3 lower header; 10 main body portion; 11 heat transfer tube; 12 plate fin; 12a first plate fin; 12b second plate fin; 12c third plate fin; 13 corrugated fin; 13a first corrugated fin; 13b second corrugated fin; 13c third corrugated fin; 13d fourth corrugated fin; 14 plate member; 15, 16, 22 arrow; 23 louver; 24 first connection; 25 second connection; 26, 27 portion; 28 end; 33 first inclined portion; 34 second inclined portion; 36 protrusion vertex; 41 compressor; 42 first heat exchanger; 43 throttle device; 44 second heat exchanger; 45 blower; 46 blower motor.

Claims

A heat exchanger comprising:
at least one heat transfer tube extending in a first direction intersecting a direction of air flow, and having refrigerant flowing therethrough;

a first plate fin extending in the first direction and spaced a first distance from the at least one heat transfer tube in a second direction perpendicular to the first direction;

a second plate fin extending in the first direction and spaced a second distance from the first plate fin in the second direction;

a first corrugated fin disposed between the at least one heat transfer tube and the first plate fin; and

a second corrugated fin disposed between the first plate fin and the second plate fin,

the first plate fin and the first corrugated fin being connected to each other by a plurality of first connections spaced a third distance from one another in the first direction,

the first plate fin and the second corrugated fin being connected to each other by a plurality of second connections spaced a fourth distance from one another in the first direction,

the third distance and the fourth distance being greater than the first distance and the second distance.
The heat exchanger according to claim 1, wherein
the direction of air flow is a direction perpendicular to the first direction and the second direction, and
a width of each of the first and second plate fins is greater than a width of each of the first and second corrugated fins in the direction of air flow.
The heat exchanger according to claim 2, wherein
a portion of each of the first and second plate fins protrudes more upstream in the direction of air flow than the first and second corrugated fins.
The heat exchanger according to claim 3, wherein
a portion of each of the first and second corrugated fins protrudes more upstream in the direction of air flow than the at least one heat transfer tube.
The heat exchanger according to any one of claims 2 to 4, further comprising a plate member connected to a portion of the at least one heat transfer tube that is located upstream in the direction of air flow.
The heat exchanger according to any one of claims 1 to 5, wherein
the first direction is a direction along the direction of gravity,
the first corrugated fin includes a first inclined portion located between the plurality of first connections and inclined relative to a vertical direction,
the second corrugated fin includes a second inclined portion located between the plurality of second connections and inclined relative to the vertical direction,
at least one louver extending linearly is formed in at least one of the first inclined portion and the second inclined portion, and
the at least one louver is formed to extend downward in the vertical direction toward upstream side in the direction of air flow.
The heat exchanger according to any one of claims 1 to 6, wherein hydrophobicity of at least a portion of surfaces of the first plate fin, the second plate fin, and the at least one heat transfer tube is higher than hydrophobicity of surfaces of the first corrugated fin and the second corrugated fin.
The heat exchanger according to any one of claims 1 to 7, wherein
a thickness of the at least one heat transfer tube is greater than a thickness of each of the first and second plate fins in the second direction, and
the thickness of each of the first and second plate fins is greater than a thickness of each of the first and second corrugated fins.
The heat exchanger according to any one of claims 1 to 8, wherein
the plurality of first connections coincide in position with the plurality of second connections in the first direction.
An air conditioning apparatus comprising a refrigerant circuit,
the refrigerant circuit including a compressor, a first heat exchanger, an expansion valve, and a second heat exchanger, and having refrigerant circulating therethrough,
at least one of the first heat exchanger and the second heat exchanger being the heat exchanger according to any one of claims 1 to 9.