AU2012208122A1

AU2012208122A1 - Heat exchanger and air conditioner

Info

Publication number: AU2012208122A1
Application number: AU2012208122A
Authority: AU
Inventors: Masanori Jindou; Yoshio Oritani; Shun Yoshioka
Original assignee: Daikin Industries Ltd
Current assignee: Daikin Industries Ltd
Priority date: 2011-01-21
Filing date: 2012-01-23
Publication date: 2012-07-26
Anticipated expiration: 2032-01-23
Also published as: AU2012208122B2; EP2667140A4; KR101451055B1; EP2667140A1; CN103403487A; JP5177307B2; ES2558783T3; KR20130127500A; EP2667140B1; CN103403487B; JP2012163318A; WO2012098916A1; US20130284416A1

Description

DESCRIPTION HEAT EXCHANGER AND AIR CONDITIONER 5 TECHNICAL FIELD [0001] The present invention relates to heat exchangers having a flat tube and fins and configured to exchange heat between a fluid flowing in the flat tube and air, and air conditioners having the heat exchangers, and specifically relates to measures for keeping a space between the fins of the heat exchanger. 10 BACKGROUND ART [0002] Heat exchangers having a flat tube and a fin have been known. For example, Patent Document 1 shows a heat exchanger in which a plurality of flat tubes, each extending in a horizontal direction, are arranged one above another with a predetermined space 15 between the flat tubes, and plate-like fins are arranged in an extension direction of the flat tubes, with a predetermined space between the fins. Air flowing in contact with the fins exchanges heat with a fluid flowing in the flat tubes. [0003] In this heat exchanger, an insertion portion of the fin in which the flat tube is inserted is provided with a fin collar, and a predetermined space is kept between the fins due 20 to the fin collar. CITATION LIST PATENT DOCUMENT [0004] Patent Document 1: Japanese Patent Publication No. 2010-054060 25 1 Dl1-422 SUMMARY OF THE INVENTION TECHNICAL PROBLEM [0005] In the conventional heat exchangers, the fin collar is formed by bending a portion of the fin which corresponds to a tube insertion portion in which the flat tube is inserted. 5 [0006] However, if the flat tube has a small thickness, the tube insertion portion of the fin has a narrow width as well, which may result in a situation where it is impossible to form a fin collar with a height that corresponds to the space between the fins by simply bending a portion of the fin that corresponds to the tube insertion portion thereof. [0007] The present invention is thus intended to make it possible to keep a predetermined 10 space between a plurality of fins. SOLUTION TO THE PROBLEM [0008] The first aspect of the present invention is a heat exchanger, including: a plurality of flat tubes (33) arranged in parallel such that side surfaces thereof face each other; and a 15 plurality of plate-like fins (36) each extending in an arrangement direction of the flat tubes (33), and having a cutout (45) to which each of the flat tubes (33) is inserted in an orthogonal direction. In the first aspect of the present invention, each of the fins (36) includes a plate like fin body (36a), and an attachment portion (36b) with which a corresponding one of the flat tubes (33) is brought into contact and to which the flat tube (33) is attached, and the fin 20 body (36a) includes a plate-like main body (36c), and a plurality of spacers (48) which are formed by bending part of the fin body (36a), continuous with the main body (36c), and keep a space between the fins (36). [0009] According to the first aspect of the present invention, the spacer (48) is formed by bending part of the fin body (36a). Thus, the spacer (48) has a sufficient height, and a 25 predetermined space is kept between the fins (36). 2 D 1l-422 [0010] The second aspect of the present invention is that in the first aspect of the present invention, the fin body (36a) has an insertion region (40) to which the flat tube (33) is inserted, and an extension region (41) continuous with one end of the insertion region (40) in an airflow direction and connecting the insertion regions (40) together, and the spacers (48) 5 are formed in both of the insertion region (40) and the extension region (41). [0011] According to the second aspect of the present invention, the spacers (48) are formed in the insertion region (40) and the extension region (41). Thus, a predetermined space is kept between the fins (36). [0012] The third aspect of the present invention is that in the second aspect of the present 10 invention, each of the fins (36) is configured such that air flows from the insertion region (40) to the extension region (41), and the spacer (48) of the extension region (41) is straight behind the spacer (48) of the insertion region (40) on a downwind side of the spacer (48) of the insertion region (40). [0013] According to the third aspect of the present invention, the spacer (48) of the 15 extension region (41) is straight behind the spacer (48) of the insertion region (40) on the downwind side of the spacer (48) of the insertion region (40). Thus, there is less effect on the spacer (48) of the extension region (41) by the airflow, and the airflow is less likely blocked. [0014] The fourth aspect of the present invention is that in the second aspect of the present 20 invention, each of the fins (36) is configured such that air flows from the insertion region (40) to the extension region (41), and the spacer (48) of the extension region (41) is behind the flat tube (33). [0015] According to the fourth aspect of the present invention, the spacer (48) is located in the dead water region behind the flat tube (33). Thus, the airflow is not blocked. 25 [0016] The fifth aspect of the present invention is that in any one of the second to fourth 3 D 1-422 aspects of the present invention, the spacer (48) of the insertion region (40) includes a flat plate-like spacer body (48a) bent to a right angle from the fin body (36a), and the spacer (48) of the insertion region (40) is tilted with respect to an airflow. [0017] According to the fifth aspect of the present invention, the spacer (48) is tilted with 5 respect to the airflow. Thus, the air resistance is reduced. [0018] The sixth aspect of the present invention is that in the third or the fourth aspect of the present invention, each of the spacers (48) is formed by cutting and bending part of the fin body (36a). [0019] According to the sixth aspect of the present invention, the spacer (48) is formed by 10 cutting and bending part of the fin body (36a). Thus, no separate member is necessary to form the spacer (48). [0020] The seventh aspect of the present invention is that in the sixth aspect of the present invention, the spacer (48) of the insertion region (40) is cut and bent from a upwind side to a downwind side, and the spacer (48) of the extension region (41) is cut and bent from the 15 downwind side to the upwind side. [0021] According to the seventh aspect of the present invention, the space between the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41) is reduced, and the space between the fins (36) is reliably kept. [0022] The eighth aspect of the present invention is that in any one of the second to 20 seventh aspects of the present invention, the insertion region (40) includes an intermediate region (42) located between the flat tubes (33), and a projection region (43) projecting toward the upwind side from the intermediate region (42) so as to be away from the extension region (41), and the spacer (48) of the insertion region (40) is provided in the projection region (43) at a middle portion through which a middle line between the flat tubes 25 (33) passes. 4 Dl 1-422 [0023] According to the eighth aspect of the present invention, the spacer (48) of the insertion region (40) is located at a middle portion between the flat tubes (33). Thus, the space between the fins (36) is reliably kept. [0024] The ninth aspect of the present invention is that in the second or fourth aspect of 5 the present invention, the insertion region (40) includes an intermediate region (42) located between the flat tubes (33), and a projection region (43) projecting toward the upwind side from the intermediate region (42) so as to be away from the extension region (41), and the spacer (48) of the insertion region (40) is bent from an edge of the projection region (43) which is a parallel edge (43b) parallel to the airflow. 10 [0025] According to the ninth aspect of the present invention, the spacer (48) is formed at a parallel edge (43b) of the projection region (43) which is parallel to the airflow. Thus, the airflow is not blocked, and the air resistance is significantly reduced. [0026] The tenth aspect of the present invention is that in the ninth aspect of the present invention, the spacer (48) of the insertion region (40) includes a flat plate-like spacer body 15 (48a) bent to a right angle from the fin body (36a), and the spacer (48) of the insertion region (40) is parallel to the airflow. [0027] According to the tenth aspect of the present invention, the spacer (48) is in parallel to the airflow. Thus, the airflow is not blocked, and the air resistance is significantly reduced. 20 [0028] The eleventh aspect of the present invention is that in any one of the first to tenth aspects of the present invention, each of the spacers (48) is in a trapezoidal shape, and a tip of the spacer (48) is a long side of the trapezoidal shape. [0029] According to the eleventh aspect of the present invention, the tip of the spacer (48) is a long side of a trapezoidal shape. Thus, a sufficient contact area with the adjacent fin 25 (36) is ensured. 5 D 11-422 [0030] The twelfth aspect of the present invention is that in any one of the first to eleventh aspects of the present invention, each of the spacers (48) is provided with a rib (48d) extending in a projection direction of the spacer (48). [0031] According to the twelfth aspect of the present invention, the spacer (48) is provided 5 with the rib (48d). Thus, the proof strength of the spacer (48) is improved. [0032] The thirteenth aspect of the present invention is that in the twelfth aspect of the present invention, the rib (48d) extends from the main body (36c) of the fin body (36a) to the spacer (48). [0033] According to the thirteenth aspect of the present invention, the rib (48d) extends 10 from the main body (36c) of the fin body (36a) to the spacer (48). Thus, the strength of the bent portion (48c) of the spacer (48) is increased. [0034] The fourteenth aspect of the present invention is that in any one of the sixth to eighth aspects of the present invention, a tip of each of the spacers (48) is off a hole (36d) that is formed in adjacent one of the fin bodies (36a) as a result of cutting and bending 15 corresponding one of the spacers (48) in the adjacent fin body (36a). [0035] According to the fourteenth aspect of the present invention, the tip of the spacer (48) is off the hole (36d) formed in the adjacent fin body (36a), and thus, the tip of the spacer (48) does not fit into the hole (36d) formed in the adjacent fin body (36a). [0036] The fifteenth aspect of the present invention is directed to an air conditioner (10) 20 including a refrigerant circuit (20) in which the heat exchanger (30) of any one of the first to fourteenth aspects of the present invention is provided, wherein the refrigerant circuit (20) performs a refrigeration cycle by circulating a refrigerant. [0037] According to the fifteenth aspect of the present invention, the heat exchanger (30) of any one of the first to fourteenth aspects of the present invention is connected to the 25 refrigerant circuit (20). In the heat exchanger (30), the refrigerant circulating in the 6 Dl1-422 refrigerant circuit (20) flows in the path (34) of the flat tube (33), and exchanges heat with the air, for example. ADVANTAGES OF THE INVENTION 5 [0038] In the present invention, part of the fin body (36a) is bent to form the spacer (48). Thus, the spacer (48) may have a sufficient height, and a predetermined space can be kept between the fins (36). [0039] In the second aspect of the present invention, the spacers (48) are formed in the insertion region (40) and the extension region (41) of the fin body (36a). Thus, a 10 predetermined space between the fins (36) can be reliably kept throughout the fins (36). [0040] In the third aspect of the present invention, the spacer (48) of the extension region (41) is straight behind the spacer (48) of the insertion region (40) on the downwind side of the spacer (48) of the insertion region (40). Thus, there is less effect on the spacer (48) of the extension region (41) by the airflow, and it is possible to reduce blocking of the airflow. 15 [0041] In the fourth aspect of the present invention, the spacer (48) is located in the dead water region behind the flat tube (33). Thus, the airflow is not blocked. [0042] In the fifth aspect of the present invention, the spacer (48) is tilted with respect to the airflow. Thus, the air resistance is reliably reduced. [0043] In the sixth aspect of the present invention, part of the fin body (36a) is cut and 20 bent to form the spacer (48). Thus, no separate member is necessary to form the spacer (48), and the structure can be simplified. [0044] In the seventh aspect of the present invention, the spacer (48) of the insertion region (40) is cut and bent from the upwind side to the downwind side, and the spacer (48) of the extension region (41) is cut and bent from the downwind side to the upwind side. Thus, 25 the space between the spacer (48) of the insertion region (40) and the spacer (48) of the 7 D 11-422 extension region (41) can be reduced, and the space between the fins (36) is reliably kept. [0045] In the eighth aspect of the present invention, the spacer (48) of the insertion region (40) is provided in the projection region (43) at a middle portion through which a middle line between the flat tubes (33) passes. Thus, the space between the fins (36) can be reliably 5 kept. [0046] In the ninth aspect of the present invention, the spacer (48) is formed at the parallel edge (43b) of the projection region (43) which is parallel to the airflow. Thus, the airflow is not blocked, and the air resistance is significantly reduced. In particular, the spacer (48) can be formed by using a portion to be removed in the formation of the fin (36). It is thus 10 possible to provide the spacer (48) with efficiency. [0047] In the tenth aspect of the present invention, the spacer (48) is in parallel to the airflow. Thus, the airflow is less blocked, and the air resistance can be further reduced. [0048] In the eleventh aspect of the present invention, the tip of the spacer (48) is a long side of a trapezoidal shape. Thus, a sufficient contact area with the adjacent fin (36) is 15 ensured, and a predetermined space between the fins (36) can be reliably kept. [0049] In the twelfth aspect of the present invention, the spacer (48) is provided with the rib (48d). Thus, the proof strength of the spacer (48) can be improved. As a result, deformation of the spacer (48) can be reliably prevented, and therefore, a predetermined space between the fins (36) can be reliably kept. 20 [0050] In the thirteen aspect of the present invention, the rib (48d) extends from the main body (36c) of the fin body (36a) to the spacer (48). Thus, the strength of the bent portion (48c) is increased, and inclination of the spacer (48) can be reliably prevented. [0051] In the fourteenth aspect of the present invention, the tip of the spacer (48) is off the hole (36d) formed in the adjacent fin body (36a) as a result of cutting and bending the 25 corresponding spacer (48) in the adjacent fin body (36a). Thus, the tip does not fit into the 8 D 11-422 hole (36d) of the adjacent fin body (36a). As a result, the spacer (48) can keep the predetermined space between the fins (36) with reliability. BRIEF DESCRIPTION OF THE DRAWINGS 5 [0052] FIG. 1 is a refrigerant circuit diagram showing a schematic configuration of an air conditioner of the first embodiment. FIG. 2 is an oblique view schematically showing the heat exchanger of the first embodiment. FIG. 3 is a partial cross-sectional view of the front side of the heat exchanger of the 10 first embodiment. FIG. 4 is a cross-sectional view of part of the heat exchanger taken along the line A-A of FIG. 3. FIG. 5 is a front view of a main part of a fin of the heat exchanger of the first embodiment. 15 FIG. 6 is a cross-sectional view taken along the line B-B of FIG. 5. FIG. 7 is a cross-sectional view of a plurality of fins of the first embodiment. FIG. 8 shows the front side of a spacer. FIG. 9 is a front view of a main part of a fin of a heat exchanger of the second embodiment. 20 FIG. 10 is a cross-sectional view of the fin of the second embodiment. FIG. 11 is a front view of a main part of a fin of the third embodiment. FIG. 12 is an oblique view of a main part of a fin before cutting and bending a spacer of the fourth embodiment. FIG. 13 is an oblique view of the main part of the fin after cutting and bending the 25 spacer of the fourth embodiment. 9 D 11-422 FIG. 14 is a plan view of the spacer of the fourth embodiment. FIG. 15 is a cross-sectional view of a spacer of the fifth embodiment. FIG. 16 is a front view of a main part of a fin of the sixth embodiment. 5 DESCRIPTION OF EMBODIMENTS [0053] Embodiments of the present invention will be described in detail below based on the drawings. [0054] <First Embodiment of Invention> A heat exchanger (30) of the first embodiment comprises an outdoor heat 10 exchanger (23) of an air conditioner (10). [0055] The air conditioner (10) having the heat exchanger (30) of the present embodiment will be described with reference to FIG. 1. [0056] -Configuration of Air Conditioner The air conditioner (10) has an outdoor unit (11) and an indoor unit (12). The 15 outdoor unit (11) and the indoor unit (12) are connected to each other via a liquid communication pipe (13) and a gas communication pipe (14). A refrigerant circuit (20) is formed by the outdoor unit (11), the indoor unit (12), the liquid communication pipe (13), and the gas communication pipe (14). [0057] The refrigerant circuit (20) includes a compressor (21), a four-way valve (22), an 20 outdoor heat exchanger (23), an expansion valve (24), and an indoor heat exchanger (25). The compressor (21), the four-way valve (22), the outdoor heat exchanger (23), and the expansion valve (24) are accommodated in the outdoor unit (11). The outdoor unit (11) is provided with an outdoor fan (15) configured to supply outdoor air to the outdoor heat exchanger (23). The indoor heat exchanger (25) is accommodated in the indoor unit (12). 25 The indoor unit (12) is provided with an indoor fan (16) configured to supply indoor air to 10 D 1-422 the indoor heat exchanger (25). [0058] A discharge side of the compressor (21) is connected to a first port of the four-way valve (22), and a suction side of the compressor (21) is connected to a second port of the four-way valve (22). In the refrigerant circuit (20), the outdoor heat exchanger (23), the 5 expansion valve (24), and the indoor heat exchanger (25) are provided sequentially from a third port to a fourth port of the four-way valve (22). [0059] The compressor (21) is a scroll type or rotary type hermetic compressor. The four-way valve (22) switches between a first state (the state shown in broken line in FIG. 1) in which the first port communicates with the third port, and the second port communicates 10 with the fourth port, and a second state (the state shown in solid line in FIG. 1) in which the first port communicates with the fourth port, and the second port communicates with the third port. The expansion valve (24) is a so-called electronic expansion valve (24). [0060] In the outdoor heat exchanger (23), the outdoor air is heat exchanged with the refrigerant. The outdoor heat exchanger (23) is comprised of the heat exchanger (30) of the 15 present embodiment. In the indoor heat exchanger (25), the indoor air is heat exchanged with the refrigerant. The indoor heat exchanger (25) is comprised of a so-called cross-fin type fin-and-tube heat exchanger having a circular heat-transfer tube. [0061] -Cooling Operation The air conditioner (10) performs a cooling operation. The four-way valve (22) is 20 set to the first state during the cooling operation. The outdoor fan (15) and the indoor fan (16) are driven during the cooling operation. [0062] The refrigerant circuit (20) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor (21) passes through the four-way valve (22), flows into the outdoor heat exchanger (23), and dissipates heat to the outdoor air and 25 condenses. The refrigerant flowing out of the outdoor heat exchanger (23) expands when it 11 D 11-422 passes through the expansion valve (24), flows into the indoor heat exchanger (25), and takes heat from the indoor air and evaporates. The refrigerant flowing out of the indoor heat exchanger (25) passes through the four-way valve (22) and is then sucked into the compressor (21) and compressed. The indoor unit (12) supplies air which has been cooled 5 in the indoor heat exchanger (25) to an indoor space. [0063] -Heating Operation The air conditioner (10) performs a heating operation. The four-way valve (22) is set to the second state during the heating operation. The outdoor fan (15) and the indoor fan (16) are driven during the heating operation. 10 [0064] The refrigerant circuit (20) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor (21) passes the four-way valve (22), flows into the indoor heat exchanger (25), and dissipates heat to the indoor air and condenses. The refrigerant flowing out of the indoor heat exchanger (25) expands when it passes through the expansion valve (24), flows into the outdoor heat exchanger (23), and takes heat from the 15 outdoor air and evaporates. The refrigerant flowing out of the outdoor heat exchanger (23) passes through the four-way valve (22) and is then sucked into the compressor (21) and compressed. The indoor unit (12) supplies air which has been heated in the indoor heat exchanger (25) to an indoor space. [0065] -Defrosting Operation 20 As described above, the outdoor heat exchanger (23) functions as an evaporator in the heating operation. In the operation under low outdoor air temperature conditions, the evaporation temperature of the refrigerant in the outdoor heat exchanger (23) may sometimes be below 0 0 C. In this case, the moisture in the outdoor air turns into frost and adheres to the outdoor heat exchanger (23). To avoid this, the air conditioner (10) performs a 25 defrosting operation every time a duration of the heating operation reaches a predetermined 12 D 1-422 value (e.g., several tens of minutes), for example. [0066] To start the defrosting operation, the four-way valve (22) is switched from the second state to the first state, and the outdoor fan (15) and the indoor fan (16) are stopped. In the refrigerant circuit (20) during the defrosting operation, a high temperature refrigerant 5 discharged from the compressor (21) is supplied to the outdoor heat exchanger (23). The frost adhering to the surface of the outdoor heat exchanger (23) is heated and melted by the refrigerant. The refrigerant which dissipates heat in the outdoor heat exchanger (23) sequentially passes through the expansion valve (24) and the indoor heat exchanger (25), and is then sucked into the compressor (21) and compressed. When the defrosting operation is 10 finished, the heating operation starts again. That is, the four-way valve (22) is switched from the first state to the second state, and the outdoor fan (15) and the indoor fan (16) are driven again. [0067] -Configuration of Heat Exchanger The heat exchanger (30) of the present embodiment which comprises the outdoor 15 heat exchanger (23) of the air conditioner (10) will be described with reference to FIGS. 2 to 8. [0068] As shown in FIG. 2 and FIG. 3, the heat exchanger (30) includes one first header collecting pipe (31), one second header collecting pipe (32), a plurality of flat tubes (33), and a plurality of fins (36). The first header collecting pipe (31), the second header collecting 20 pipe (32), the flat tubes (33), and the fins (36) are all aluminum alloy members, and are attached to one another with solder. The flat tubes (33) and the fins (36) are provided such that the width direction thereof is along the airflow, and the flat tubes (33) and the fins (36) are arranged to be orthogonal to each other in a grid pattern. [0069] Both of the first header collecting pipe (31) and the second header collecting pipe 25 (32) are in an elongated cylindrical shape. One of the first header collecting pipe (31) and 13 D 1l-422 the second header collecting pipe (32) is provided at the left end of the heat exchanger (30), and the other is provided at the right end of the heat exchanger (30). As shown in FIG. 4, each of the flat tubes (33) is a heat-transfer tube having a flat cross section, and the flat tubes (33) are arranged one above another such that the flat surfaces thereof face each other. 5 Each flat tube (33) has a plurality of fluid passages (34). One end of each of the flat tubes (33) arranged one above another is inserted in the first header collecting pipe (31), and the other end is inserted in the second header collecting pipe (32). [0070] Each fin (36) is in a plate-like shape, and the fins (36) are arranged in an extension direction of the flat tube (33) with a predetermined space between the fins (36). In other 10 words, the fins (36) are arranged to be substantially orthogonal to the extension direction of the flat tube (33). [0071] As shown in FIG. 5, each fin (36) is in an elongated plate-like shape formed by pressing a metal plate. The fin (36) includes a plate-like fin body (36a) and an attachment portion (36b) by which the flat tube (33) is attached to the fin body (36a). 15 [0072] That is, the fin (36) is provided with a plurality of elongated cutouts (45) each extending in a width direction of the fin (36) from a leading edge (39) of the fin (36), and corresponding to the flat tubes (33). The plurality of cutouts (45) are formed in the fin (36) at predetermined intervals in a longitudinal direction (i.e., a vertical direction) of the fin (36). The cutouts (45) are configured such that the flat tubes (33) are inserted therein. A 20 downwind portion of the cutout (45) comprises a tube insertion portion (46) in which the flat tube (33) is inserted. A width of the tube insertion portion (46) in the vertical direction is substantially equal to the thickness of the flat tube (33), and a length of the tube insertion portion (46) is substantially equal to the width of the flat tube (33). [0073] An edge portion of the tube insertion portion (46) of the fin (36) serves as the 25 attachment portion (36b). Specifically, the edge portion of the tube insertion portion (46) is 14 D 11-422 provided with a collar to serve as the attachment portion (36b). The flat tube (33) is inserted in the tube insertion portion (46) to be in contact with the attachment portion (36b), and is attached to the attachment portion (36b) with solder, thereby attaching the flat tube (33) to the fin body (36a). 5 [0074] The fin body (36a) includes an insertion region (40) into which the flat tube (33) is inserted, and an extension region (41) that is continuous with one end, in the airflow direction, of each insertion region (40) and connecting the insertion regions (40). That is, the insertion region (40) is located on the upwind side of the air, and the extension region (41) is located on the downwind side of the insertion region (40). 10 [0075] The insertion region (40) includes an intermediate region (42) located between the flat tubes (33), and a projection region (43) which projects from the intermediate region (42) in a direction away from the extension region (41). That is, the projection region (43) is on the most upwind side of the air; the intermediate region (42) is located on the downwind side of the projection region (43); and the extension region (41) is located on the downwind side 15 of the intermediate region (42). [0076] A plurality of louvers (50) are provided in the insertion region (40) and the extension region (41) of the fin body (36a). Each of the louvers (50) comprises a heat transfer promotion portion, and is formed by cutting and bending part of the insertion region (40) and the extension region (41) as shown in FIG. 6 and FIG. 7. That is, the louvers (50) 20 are formed by giving a plurality of slit-like cuts in the insertion region (40) and the extension region (41) and plastically deforming a portion between adjacent cuts as if twisting the portion. [0077] The longitudinal direction of each louver (50) is substantially parallel to the leading edge (38) of the projection region (43). That is, the longitudinal direction of each 25 louver (50) is the vertical direction. The plurality of louvers (50) are arranged next to each 15 D 1l-422 other from the upwind side to the downwind side. [0078] A water-conducting rib (71) is formed in the extension region (41) of the fin body (36a). The water-conducting rib (71) is an elongated recessed groove extending vertically along a downwind side edge of the extension region (41). The water-conducting rib (71) 5 extends from the upper end to the lower end of the extension region (41). [0079] The fin body (36a) is provided with a spacer (48) configured to keep a space between adjacent fins (36). [0080] As shown in FIG. 4 to FIG. 7, the spacer (48) is provided in each of the extension region (41) of the fin body (36a) and the projection region (43) of the insertion region (40). 10 The spacer (48) of the extension region (41) corresponds to the tube insertion portion (46), and one spacer (48) is located behind each of the flat tubes (33), that is, located on the downwind side of the flat tube (33). The spacer (48) of the insertion region (40) is provided such that one spacer (48) is located in each of the projection regions (43) at a position on the upwind side of the most upwind side louver (50) and a middle portion of the projection 15 region (43). That is, the spacer (48) of the insertion region (40) is located in the projection region (43) at a middle portion through which a middle line between the flat tubes (33) passes. The middle portion includes a portion that is on the middle line between the flat tubes (33), and also a portion that is off the middle line to a certain extent. [0081] The spacer (48) is formed by bending part of the fin body (36a), specifically by 20 cutting and bending part of the fin body (36a). That is, the fin body (36a) includes a plate like main body (36c) having the insertion region (40) and the extension region (41), and the spacer (48) continuous with the main body (36c). The spacer (48) is raised at a right angle from the main body (36c) of the fin body (36a) via a bent portion (48c). On the other hand, a hole (36d) is formed in the fin body (36a) as a result of cutting and bending the spacer (48). 25 [0082] As shown in FIG. 8, the spacer (48) is comprised of a flat plate-like spacer body 16 D 1l-422 (48a) bent at a right angle from the fin body (36a), and an arc-shaped curved portion (48b) at the tip of the spacer body (48a). The spacer (48) has a trapezoidal shape in which the tip thereof, i.e., the edge of the curved portion (48b) is the long side. Further, the tip of the spacer (48) is off the hole (36d) that is formed in the adjacent fin body (36a) as a result of 5 cutting and bending a corresponding spacer (48) in the adjacent fin body (36a). The spacer (48) is configured such that the tip is in contact with the main body (36c) of the adjacent fin body (36a) at a location near the hole (36d). [0083] The spacer (48) of the extension region (41) is formed in a dead water region formed by the flat tube (33), and a width of the spacer (48) of the extension region (41) is 10 approximately the same as the thickness of the flat tube (33). The spacer (48) of the extension region (41) is formed such that the flat surface thereof is orthogonal to the airflow. That is, the width direction and the height direction of the spacer (48) of the extension region (41) are orthogonal to the airflow. [0084] On the other hand, the spacer (48) of the insertion region (40) is formed such that 15 the flat surface thereof is tilted with respect to the airflow. The spacer (48) is tilted from one side to the other side of the spacer (48) with respect to the downwind direction so that the air resistance may be reduced. That is, the height direction of the spacer (48) of the insertion region (40) is orthogonal to the airflow, and the width direction of the spacer (48) of the insertion region (40) is tilted with respect to the airflow. 20 [0085] The spacer (48) of the insertion region (40) is cut and bent from the upwind side to the downwind side. The spacer (48) of the extension region (41) is cut and bent from the downwind side to the upwind side. This means that the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41) are formed such that the space between the spacers (48) is reduced. 25 [0086] The tips of the curved portions (48b) of the spacers (48) of the extension region 17 D 1-422 (41) and the insertion region (40) are in contact with the main body (36c) of the adjacent fin body (36a), and keep a predetermined space between adjacent fin bodies (36a). [0087] -Advantages of First Embodiment In the present embodiment, part of the fin body (36a) is bent to form the spacer 5 (48). Thus, the spacer (48) may have a sufficient height, and a predetermine space can be kept between the fins (36) with reliability. [0088] The spacers (48) are formed in the insertion region (40) and the extension region (41) of the fin body (36a). Thus, a predetermine space can be kept between the fins (36) with reliability throughout the fins (36). 10 [0089] The spacer (48) of the extension region (41) is located in the dead water region behind the flat tube (33). Thus, the airflow is not blocked. [0090] The spacer body (48a) of the insertion region (40) is tilted with respect to the airflow. Thus, the air resistance can be reduced with reliability. [0091] Part of the fin body (36a) is cut and bent to form the spacer (48). Thus, no 15 separate member is necessary to form the spacer (48), and the structure can be simplified. [0092] The spacer (48) of the insertion region (40) is cut and bent from the upwind side to the downwind side, and the spacer (48) of the extension region (41) is cut and bent from the downwind side and the upwind side. Thus, the space between the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41) can be reduced, and the 20 space between the fins (36) is reliably kept. [0093] The spacer (48) of the insertion region (40) is located in the projection region (43) at a middle portion through which the middle line between the flat tubes (33) passes. Thus, the space between the fins (36) is reliably kept. [0094] The tip of each spacer (48) is a long side. Thus, a sufficient contact area with the 25 adjacent fin (36) can be ensured, and a predetermined space between the fins (36) can be 18 D 1l-422 reliably kept. [0095] The tip of the spacer (48) is off the hole (36d) that is formed in the adjacent fin body (36a) as a result of cutting and bending a corresponding spacer (48) in the adjacent fin body (36a). Thus, the tip does not fit into the hole (36d) of the adjacent fin body (36a). 5 As a result, the spacer (48) can keep a predetermined space between the fins (36) with reliability. [0096] <Second Embodiment of Invention> Now, the second embodiment of the present invention will be described in detail, based on the drawings. 10 [0097] In the present embodiment, spacers (48) of the insertion region (40) are provided at edges of the projection region (43), as shown in FIG. 9 and FIG. 10, instead of providing the spacer (48) of the insertion region (40) at the middle portion of the projection region (43) as in the first embodiment. [0098] Specifically, both sides of the projection region (43) of the fin body (36a) include a 15 gently-inclined edge (43a) which is gently inclined toward the downwind side from the leading edge (38) due to the cutout (45), a parallel edge (43b) continuous with the gently inclined edge (43a) and parallel with the airflow, and a steeply-inclined edge (43c) which is continuous with the parallel edge (43b) and is steeply inclined toward the downwind side. The tube insertion portion (46) is continuous with the steeply-inclined edge (43c). 20 [0099] The spacers (48) of the insertion region (40) are bent from the parallel edges (43b) on both sides of the projection region (43). Each of the spacers (48) of the insertion region (40) has a trapezoidal shape, and includes a spacer body (48a) and a curved portion (48b), similar to the spacer (48) of the first embodiment. The spacer body (48a) is bent at a right angle from the projection region (43), and parallel with the airflow. 25 [0100] The tips of the curved portions (48b) of the spacers (48) of the insertion region (40) 19 D 1-422 are in contact with edge portions of the projection region (43) of the adjacent fin body (36a), and keep a predetermined space between the adjacent fin bodies (36a). [0101] In the second embodiment, a protrusion (60), i.e., a heat-transfer promotion portion, is formed by bending the fin body (36a) into an inverted V shape, instead of the 5 upwind side louvers (50) of the first embodiment. The other configurations and effects are similar to those in the first embodiment. In particular, the spacer (48) of the extension region (41) is similar to the spacer (48) of the extension region (41) in the first embodiment. [0102] -Advantages of Second Embodiment In the present embodiment, the spacers (48) are provided at the parallel edges (43b) 10 of the projection region (43) which are parallel with the airflow. Thus, the airflow is not blocked, and the air resistance can be significantly reduced. In particular, the spacer (48) can be formed by using a portion to be removed in the formation of the fin (36). It is thus possible to provide the spacer (48) with efficiency. [0103] The spacer body (48a) is parallel to the airflow. Thus, the airflow is not blocked, 15 and the air resistance can be further reduced. The advantages of other configurations, e.g., the spacer (48) of the extension region (41) are similar to those of the first embodiment. [0104] <Third Embodiment of Invention> Now, the third embodiment of the present invention will be described in detail, based on the drawings. 20 [0105] In the present embodiment, the spacer (48) of the extension region (41) is straight behind the spacer (48) of the insertion region (40), as shown in FIG. 11, instead of the spacer (48) of the extension region (41) provided behind the flat tube (33) in the first embodiment. [0106] Specifically, the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41) are provided at the middle portion through which the middle line 25 between the flat tubes (33) passes. The spacer (48) of the extension region (41) is straight 20 Dl1-422 behind the spacer (48) of the insertion region (40) on the downwind side of the spacer (48) of the insertion region (40). The middle portion includes a portion that is on the middle line between the flat tubes (33), and also a portion that is off the middle line to a certain extent. [0107] Similar to the first embodiment, the spacer (48) of the insertion region (40) is tilted 5 with respect to the airflow, and the spacer (48) of the extension region (41) is orthogonal to the airflow, similar to the first embodiment. [0108] In particular, the spacer (48) of the insertion region (40) is cut and bent from the upwind side to the downwind side, and the spacer (48) of the extension region (41) is cut and bent from the downwind side to the upwind side. This means that the spacer (48) of the 10 insertion region (40) and the spacer (48) of the extension region (41) are formed such that the space between the spacers (48) is reduced. [0109] On the other hand, the fin body (36a) of the present embodiment is provided with a protrusion (60), i.e., a heat-transfer promotion portion, which is formed by bending the fin body (36a) into an inverted V shape as described in the second embodiment, instead of the 15 upwind side louvers (50) of the first embodiment. Further, another protrusion (60), i.e., a heat-transfer promotion portion, is provided in place of the louver (50) of the downwind side louvers (50) in the first embodiment, which is located on the downwind side of the intermediate region (42) of the insertion region (40). [0110] Further, another protrusion (60), i.e., the heat-transfer promotion portion described 20 in the second embodiment, is provided in the extension region (41) of the fin body (36a). The protrusion (60) of the extension region (41) is located behind the flat tube (33), and the air flowing along the flat tube (33) in the space between the flat tube (33), and the louvers (50) and the protrusion (60), exchanges heat with the protrusion (60) of the extension region (41). 25 [0111] The spacer (48) of the extension region (41) is located at a position between the 21 D 1-422 protrusions (60) of the extension region (41). The other configurations and effects are similar to those in the first embodiment. In particular, the spacer (48) of the extension region (41) is similar to the spacer (48) of the extension region (41) in the first embodiment. [0112] -Advantages of Third Embodiment 5 In the present embodiment, the spacer (48) of the extension region (41) is straight behind the spacer (48) of the insertion region (40) on the downwind side of the spacer (48) of the insertion region (40). Thus, there is less effect on the spacer (48) of the extension region (41) by the airflow, and it is possible to reduce blocking of the airflow. [0113] Similar to the first embodiment, the spacer (48) of the insertion region (40) is cut 10 and bent from the upwind side to the downwind side, and the spacer (48) of the extension region (41) is cut and bent from the downwind side to the upwind side. Thus, the space between the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41) can be reduced, and the space between the fins (36) can be reliably kept. [0114] The spacer (48) of the insertion region (40) is located in the projection region (43) 15 at a middle portion through which the middle line between the flat tubes (33) passes. Thus, the space between the fins (36) is reliably kept. [0115] The spacer (48) of the extension region (41) is located between the protrusions (60) of the extension region (41). Thus, it is possible to promote heat exchange of the air flowing on the lateral sides of the flat tube (33) and keep the space between the fins (36) with 20 reliability. The other advantages are the same as those in the first embodiment. [0116] <Fourth Embodiment of Invention> Now, the fourth embodiment of the present invention will be described in detail, based on the drawings. [0117] In the present embodiment, a rib (48d) is provided at the spacer (48) of the third 25 embodiment as shown in FIG. 12 to FIG. 14. 22 DI1-422 [0118] The rib (48d) is a linear raised portion extending in a projection direction of the spacer (48), and one rib (48d) is provided at the spacer (48). The rib (48d) is located in a middle portion of the spacer body (48a). The tip of the rib (48d) is located at the tip of the spacer body (48a). The rib (48d) extends from the spacer body (48a) via the bent portion 5 (48c), and the base end of rib (48d) is located at the main body (36c) of the fin body (36a) In other words, the rib (48d) is bent at the bent portion (48c), and the rib (48d) is not provided at the curved portion (48b) of the spacer (48). [0119] The rib (48d) is provided to increase the strength of the spacer (48) in the projection direction, because the thickness of the fin (36) is small and thus if the spacer (48) 10 is formed by simply cutting and bending the fin body (36a), the spacer (48) has low proof strength and is easily deformed. As shown in FIG. 12, the rib (48d) is formed in a state in which the spacer (48) is not cut and bent from the fin body (36a) yet. In this state, the rib (48d) projects in the same direction as the projection direction of the protrusion (60). After that, the spacer (48) is cut and bent from the fin body (36a) as shown in FIG. 13. 15 [0120] The rib (48d) is provided at each of the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41). The rib (48d) may include a plurality of ribs (48d). The other configurations are similar to those in the third embodiment. The spacers (48) of the first and second embodiments may be provided with the rib (48d). [0121] As described, since the rib (48d) is provided at the spacer (48) in the present 20 embodiment, the proof strength of the spacer (48) can be increased. As a result, deformation of the spacer (48) can be reliably prevented, and therefore, a predetermined space between the fins (36) can be reliably kept. [0122] The rib (48d) extends from the main body (36c) of the fin body (36a) to the spacer (48). Thus, the strength of the bent portion (48c) is increased, and inclination of the spacer 25 (48) can be reliably prevented. The other effects and advantages are similar to those of the 23 Dl 1-422 third embodiment. [0123] <Fifth Embodiment of Invention> Now, the fifth embodiment of the present invention will be described in detail, based on the drawings. 5 [0124] In the present embodiment, as shown in FIG. 15, the spacer (48) is in an L shape in place of the spacer (48) of the fourth embodiment which is comprised of the spacer body (48a) and the curved portion (48b). [0125] Specifically, the spacer (48) includes a first portion (48e) on the base end side, and a second portion (48f) on the tip side. The first portion (48e) and the second portion (48f) 10 are flat plate-like portions. The first portion (48e) extends obliquely upward toward the hole (36d), from the main body (36c) of the fin body (36a) through the bent portion (48c). The second portion (48f) is bent from the first portion (48e) at about a right angle, and extends obliquely upward in a direction away from the hole (36d). The spacer (48) is configured such that the tip of the second portion (48f) is in contact with the adjacent fin 15 body (36a). [0126] Further, a rib (48d) is provided at the spacer (48), similar to the fourth embodiment. The rib (48d) extends from the main body (36c) of the fin body (36a) to near the tip of the second portion (48f) via the first portion (48e). The other configurations, effects and advantages are similar to those in the fourth embodiment. That is, the spacer 20 (48) of the present embodiment is applied to the spacer (48) of the insertion region (40) and the spacer (48) of the extension region (41), and may also be applied to the spacers (48) in the first to third embodiments. In other words, the spacer (48) of the present embodiment may not have the rib (48d). [0127] <Sixth Embodiment of Invention> 25 Now, the sixth embodiment of the present invention will be described in detail, 24 D 1l-422 based on the drawings. [0128] In the present embodiment, as shown in FIG. 16, horizontal ribs (61, 62), i.e., heat transfer promotion portions, are provided at the fin body (36a) of the third embodiment. [0129] Specifically, the fin (36) is provided with two horizontal ribs (61, 62) extending 5 from the projection region (43) to the intermediate region (42). Each of the horizontal ribs (61, 62) is a raised line which projects in the same protruding direction as the protrusion (60). The horizontal ribs (61, 62) are formed in an upper portion and a lower portion of the projection region (43) of the fin (36), and extends horizontally from the leading edge (38) of the fin (36) to the second protrusion (60) from the upwind side. 10 [0130] That is, the two horizontal ribs (61, 62) linearly extend in the projection direction of the projection region (43) of the fin (36) (i.e., the air passage direction). The horizontal ribs (61, 62) comprise reinforcement ribs which prevent the projection region (43) of the fin (36) from being bent toward the adjacent fin (36). The horizontal ribs (61, 62) further comprise heat-transfer portions which promote heat transfer between the fin (36) and air in 15 an area located upwind of the intermediate region (42). [0131] As described, the horizontal ribs (61, 62) which extend from the projection region (43) to the intermediate region (42) of the fin (36) are provided in the present embodiment. Thus, the air before flowing in between the fins (36) can be cooled and dehumidified. As a result, the accumulation of frost on the surface of the intermediate region (42) of the fin (36) 20 is reduced, and therefore, it is possible to prevent a reduction in heat-transfer rate of the fin (36) due to the accumulation of frost, and an increase in flow pass resistance of the air passages (40). [0132] <Other Embodiments> The first and second embodiments of the present invention may have the following 25 configurations. 25 D 1-422 [0133] In the first aspect of the invention, the locations of the spacers (48) are not limited to the insertion region (40) and the extension region (41) of the fin body (36a), but the spacer (48) may be formed only in the insertion region (40) of the fin body (36a), or in the extension region (41) of the fin body (36a). 5 [0134] The number of spacers (48) of the insertion region (40) and the extension region (41) is not limited as described in the first and second embodiments, but the spacer (48) may be provided so as to correspond to every other flat tube (33), for example. [0135] The spacers (48) of the insertion region (40) of the second embodiment may be provided at only one side of the projection region (43). 10 [0136] The shape of the spacer (48) is not limited to a trapezoidal shape in the first aspect of the invention, for example. [0137] The spacer (48) of the insertion region (40) and the spacer (48) of the projection region (43) in the third embodiment do not necessarily have to be formed in the middle portion through which the middle line between the flat tubes (33) passes, and may be located 15 closer to one of the flat tubes (33). [0138] The protrusion (60) of the extension region (41) of the third embodiment may be the louver (50) of the first embodiment. [0139] The rib (48d) of the fourth embodiment may be provided at only the spacer (48), and may not be provided at the main body (36c) of the fin body (36a). 20 [0140] The foregoing embodiments are merely preferred examples in nature, and are not intended to limit the scope, applications, and use of the invention. INDUSTRIAL APPLICABILITY [0141] As described above, the present invention is useful for heat exchangers having a 25 flat tube and a fin, and air conditioners having the heat exchangers. 26 D 11-422 DESCRIPTION OF REFERENCE CHARACTERS [0142] 30 heat exchanger 33 flat tube 5 36 fin 36a fin body 36b attachment portion 36c main body 36d hole 10 40 insertion region 41 extension region 42 intermediate region 43 projection region 43b parallel edge 15 45 cutout 46 tube insertion portion 48 spacer 48a spacer body 48b curved portion 20 48c bent portion 48d rib 27 Dll-422

Claims

1. A heat exchanger, comprising: a plurality of flat tubes (33) arranged in parallel such that side surfaces thereof face 5 each other; and a plurality of plate-like fins (36) each extending in an arrangement direction of the flat tubes (33), and having a cutout (45) to which each of the flat tubes (33) is inserted in an orthogonal direction, wherein each of the fins (36) includes a plate-like fin body (36a), and an attachment portion 10 (36b) with which a corresponding one of the flat tubes (33) is brought into contact and to which the flat tube (33) is attached, and the fin body (36a) includes a plate-like main body (36c), and a plurality of spacers (48) which are formed by bending part of the fin body (36a), continuous with the main body (36c), and keep a space between the fins (36). 15

2. The heat exchanger of claim 1, wherein the fin body (36a) has an insertion region (40) to which the flat tube (33) is inserted, and an extension region (41) continuous with one end of the insertion region (40) in an airflow direction and connecting the insertion regions (40) together, and 20 the spacers (48) are formed in both of the insertion region (40) and the extension region (41).

3. The heat exchanger of claim 2, wherein each of the fins (36) is configured such that air flows from the insertion region (40) 25 to the extension region (41), and 28 D 11-422 the spacer (48) of the extension region (41) is straight behind the spacer (48) of the insertion region (40) on a downwind side of the spacer (48) of the insertion region (40).

4. The heat exchanger of claim 2, wherein 5 each of the fins (36) is configured such that air flows from the insertion region (40) to the extension region (41), and the spacer (48) of the extension region (41) is behind the flat tube (33).

5. The heat exchanger of claim 3 or 4, wherein 10 the spacer (48) of the insertion region (40) includes a flat plate-like spacer body (48a) bent to a right angle from the fin body (36a), and the spacer (48) of the insertion region (40) is tilted with respect to an airflow.

6. The heat exchanger of any one of claims 3-5, wherein 15 each of the spacers (48) is formed by cutting and bending part of the fin body (36a).

7. The heat exchanger of claim 6, wherein the spacer (48) of the insertion region (40) is cut and bent from a upwind side to a 20 downwind side, and the spacer (48) of the extension region (41) is cut and bent from the downwind side to the upwind side.

8. The heat exchanger of any one of claims 3-7, wherein 25 the insertion region (40) includes an intermediate region (42) located between the 29 Dl1-422 flat tubes (33), and a projection region (43) projecting toward the upwind side from the intermediate region (42) so as to be away from the extension region (41), and the spacer (48) of the insertion region (40) is provided in the projection region (43) at a middle portion through which a middle line between the flat tubes (33) passes. 5

9. The heat exchanger of claim 2 or 4, wherein the insertion region (40) includes an intermediate region (42) located between the flat tubes (33), and a projection region (43) projecting toward the upwind side from the intermediate region (42) so as to be away from the extension region (41), and 10 the spacer (48) of the insertion region (40) is bent from an edge of the projection region (43) which is a parallel edge (43b) parallel to the airflow.

10. The heat exchanger of claim 9, wherein the spacer (48) of the insertion region (40) includes a flat plate-like spacer body 15 (48a) bent to a right angle from the fin body (36a), and the spacer (48) of the insertion region (40) is parallel to the airflow.

11. The heat exchanger of any one of claims 1-10, wherein each of the spacers (48) is in a trapezoidal shape, and a tip of the spacer (48) is a 20 long side of the trapezoidal shape.

12. The heat exchanger of any one of claims 1-11, wherein each of the spacers (48) is provided with a rib (48d) extending in a projection direction of the spacer (48). 25 30 D 11-422

13. The heat exchanger of claim 12, wherein the rib (48d) extends from the main body (36c) of the fin body (36a) to the spacer (48). 5

14. The heat exchanger of any one of claims 6-8, wherein a tip of each of the spacers (48) is off a hole (36d) that is formed in adjacent one of the fin bodies (36a) as a result of cutting and bending corresponding one of the spacers (48) in the adjacent fin body (36a). 10

15. An air conditioner, comprising a refrigerant circuit (20) in which the heat exchanger (30) of any one of claims 1-14 is provided, wherein the refrigerant circuit (20) performs a refrigeration cycle by circulating a refrigerant. 31 D 1l-422