WO2019004139A1 - Heat exchanger - Google Patents

Abstract

A heat exchanger that easily ensures the pressure resistance of a flat multi-hole tube while sufficiently performing performance on both the upwind side and the downwind side in the air flow direction even when delaying the increase in ventilation resistance due to the adhesion of frost I will provide a. A flat multi-hole pipe (63) having a plurality of passages (63b) aligned in the air flow direction and a notch (64a) cut out toward the wind side from the leeward side in the air flow direction (63) is inserted and fixed, and provided with a fin (64) having a communicating portion (64x) connected vertically on the windward side of the flat multi-hole pipe (63); 0.18 ≦ L / Wt ≦ 0 And satisfy the relationship 2 ≦ a / b ≦ 16. Here, L: distance in the air flow direction from the wind upper end of the flat multi-hole pipe (63) to the wind upper end of the fin (64) Wt: length in the air flow direction of the flat multi-hole pipe (63) a: The sum of the widths in the air flow direction of the first and second passages (63b) from the windward side in the flat multi-hole pipe (63), b: the middle passage (63b) in the air flow direction in the flat multi-hole pipe (63) Width of the air flow direction of

Description

Heat exchanger

The present disclosure relates to a heat exchanger.

Conventionally, heat exchange is performed, which includes a plurality of flat multi-hole pipes and fins joined to the plurality of flat multi-hole pipes, and causes the refrigerant flowing inside the flat multi-hole pipes to exchange heat with air flowing outside the flat multi-hole pipes. The vessel is known.

For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2002-139282), a heat exchanger is proposed in which a notch is formed in the fin from the windward side to the windward side, and a flat multi-hole tube is inserted and fixed from the windward side of the fin. It is done.

In the heat exchanger disclosed in Patent Document 1, the fins are not provided on the windward side of the wind upper end of the flat multi-hole tube. For this reason, when a heat exchanger is used as an evaporator whose evaporation temperature is low in an environment where the outside air temperature is low, frost adheres intensively to the fins of the heat exchanger and the windward portion of the flat multi-hole tube. As a result, the increase in ventilation resistance tends to occur early. For this reason, it becomes necessary to frequently perform an operation or the like for melting the frost adhering to the heat exchanger.

On the other hand, by providing the fins also on the windward side further than the wind upper end of the flat multi-hole pipe, it becomes possible to alleviate the state in which the frost adheres intensively to the windward part of the flat multi-hole pipe. .

However, when the fins are provided further on the windward side than the wind upper end of the flat multi-hole tube in this manner, the difference between the air temperature and the refrigerant temperature on the windward side is large and the air flow direction is not good. In addition to the balance, the amount of heat flux from the fins for the refrigerant flow path on the windward side among the plurality of refrigerant flow paths provided in the flat multi-hole pipe becomes larger than the amount of heat flux for the refrigerant flow path on the windward side An imbalance in the air flow direction may occur. If this imbalance occurs, the refrigerant flowing in the refrigerant flow path on the windward side of the flat multi-hole tube evaporates completely in the middle of the flow path, but the refrigerant flowing in the refrigerant flow path on the windward side fully evaporates. For example, there is a possibility that the heat exchanger can not exhibit its performance sufficiently.

The present disclosure has been made in view of the above-described points, and the problem of the present disclosure is that both the upwind and downwind sides in the air flow direction are sufficient even if the increase in ventilation resistance due to the deposition of frost is delayed. It is an object of the present invention to provide a heat exchanger which is easy to secure the pressure resistance of a flat multi-hole tube while exerting the performance thereof.

The heat exchanger which concerns on a 1st viewpoint is provided with the flat multi-hole pipe and the fin. The flat multi-hole pipe has a plurality of refrigerant flow channels aligned in the air flow direction. In the fin, a flat multi-hole tube is inserted and fixed at a location where it is notched from the downwind side to the upwind side in the air flow direction. The fin has a portion connected up and down on the windward side of the flat multi-hole tube. L: Distance in the air flow direction from the wind upper end of the flat multi-hole pipe to the wind upper end of the fin, Wt: Length in the air flow direction of the flat multi-hole pipe, a: First and second from the windward side of the flat multi-hole pipe 0.18 ≦ L / Wt ≦ a total value of the width in the air flow direction of the second refrigerant flow path, b: the width in the air flow direction of the refrigerant flow path in the middle of the air flow direction in the flat multi-hole pipe 0.32 and the relationship of 2 ≦ a / b ≦ 16 is satisfied.

In the case of “b”, when there is no refrigerant channel at the center of the flat multi-hole pipe (for example, there is a partition that divides each refrigerant channel), the width of the refrigerant channel closest to the center from the center It may be the average value of the widths of the two refrigerant flow paths sandwiching the center.

The average length in the air flow direction of each refrigerant flow passage located on the windward side relative to the average length in the air flow direction of each refrigerant flow passage located on the downwind side including the center of the flat multi-hole pipe Preferably it is larger.

In this heat exchanger, the fins have a portion connected up and down on the windward side of the flat multi-hole tube, and 0.18 ≦ L / Wt on the windward side of the flat multi-hole tube of the fin Since the area capable of frost formation is widely secured, it is possible to improve the frost resistance. For this reason, it is possible to eliminate the need to frequently perform the defrosting process / operation which is performed to melt the frost adhering to the heat exchanger. In addition, since the portion on the windward side of the flat multi-hole tube of the fin is configured to satisfy the relationship of L / Wt ≦ 0.32, unnecessary portions that hardly contribute to the improvement of the frost resistance are reduced. This makes it possible to reduce the material cost of the fins.

Here, the temperature difference between the air passing through the outside of the flat multi-hole pipe and the refrigerant passing through the refrigerant flow path of the flat multi-hole pipe tends to be larger on the windward side in the air flow direction than on the windward side. . For this reason, in a plurality of refrigerant channels provided in parallel in the air flow direction in the flat multi-hole pipe, the windward side of the air flow tends to have a larger amount of heat exchange than the windward side. And, in the structure in which the fin is positioned on the windward side of the flat multi-hole tube in order to improve the frost resistance as described above, with respect to the windward side portion of the plurality of refrigerant channels of the flat multi-hole pipe Further, since the heat flux from the fins located on the windward side is supplied, the amount of heat exchange in the refrigerant flow path on the windward side of the air flow tends to be larger than the refrigerant flow path on the windward side .

Even in such a structure, in this heat exchanger, the refrigerant flow path on the leeward side of the refrigerant flow paths in the flat multi-hole pipe is set to the refrigerant flow on the windward side by satisfying the relationship 2 ≦ a / b. By making the flow path on the windward side larger than the flow path of the flat multi-hole tube without making the path larger than the path, the amount of heat flux supplied from the surrounding fins is made to correspond. This makes it possible to improve the performance of the heat exchanger. It is more preferable to satisfy the relationship of 2.5 ≦ a / b.

Moreover, in such a structure, in this heat exchanger, the size of the relatively large refrigerant flow path on the windward side of the flat multi-hole tube is set by satisfying the relationship of a / b ≦ 16. Comparison of the windward side of the flat multi-hole tube by ensuring that the size of the air flow direction does not become too large (by not making the size of the air flow direction excessive with respect to the length in the direction perpendicular to the air flow direction) It is easy to secure the pressure resistance even in the extremely large refrigerant flow path.

As described above, although the structure for delaying the increase in the ventilation resistance due to the adhesion of the frost is adopted, the performance is sufficiently satisfied in both the refrigerant flow path on the windward side and the refrigerant flow path on the windward side in the air flow direction It is possible to secure the pressure resistance of the flat multi-hole tube while making it exhibit.

The heat exchanger according to the second aspect is the heat exchanger according to the first aspect, and satisfies the relationship of 0.21 ≦ L / Wt ≦ 0.32. The wind lower end of the fin is located further downwind in the air flow direction than the wind lower end of the flat multi-hole tube.

In this heat exchanger, the frost resistance can be more reliably improved by securing a portion on the windward side more sufficiently than the flat multi-hole pipe among the fins. Furthermore, since the wind lower end of the fin is located further leeward in the air flow direction than the wind lower end of the flat multi-hole tube, the condensed water is made downward from the windward lower end of the fin projecting to the leeward side. It is possible to improve the drainage efficiency of condensed water by dropping it.

The heat exchanger pertaining to the third aspect is the heat exchanger pertaining to the second aspect, wherein the wind lower end of the fin is located further leeward than the wind lower end of the flat multi-hole tube by 2 mm or more.

Generally, in the structure in which dew condensation water is supplied to the wind lower end of the fin, when the frost adheres to the wind lower end of the fin of the heat exchanger, the frost may grow.

On the other hand, in this heat exchanger, the wind lower end of the fin is further separated by 2 mm or more from the wind lower end of the flat multi-hole tube at the leeward side. For this reason, the condensation water which flows down from the wind lower end of a flat multi-hole pipe is hard to be supplied to the wind lower end of a fin, and it becomes possible to control the growth of the frost in the wind lower end of a fin.

A heat exchanger according to a fourth aspect is the heat exchanger according to the first aspect, and satisfies the relationship of 0.18 ≦ L / Wt ≦ 0.30. The wind lower end of the flat multi-hole tube is located further downwind in the air flow direction than the wind lower end of the fin.

In this heat exchanger, the portion on the windward side of the flat multi-hole tube of the fin is configured to satisfy the relationship of L / Wt ≦ 0.30, so it is unnecessary to contribute to the improvement of the frost resistance. By sufficiently reducing the parts, it is possible to sufficiently reduce the material cost of the fins.

Further, in this heat exchanger, the wind lower end of the flat multi-hole tube is located further downwind than the wind lower end of the fin, so the flat multi-hole tube protrudes not the fins toward the lee side The configuration can be made to be able to protect the downwind side of the fin during manufacture or transport.

In addition, by using a configuration in which the flat multi-hole pipe is protruded to the downwind side instead of the fins, for example, when bending the heat exchanger, the tool is pressed against the flat multi-hole pipe to work. It is possible to suppress deformation and damage of the leeward fin. Moreover, when brazing in a furnace, not a fin but a flat multi-hole pipe can be grounded, and it is also possible to suppress thermal contraction and deformation of the fin caused by the grounding of the fin.

A heat exchanger according to a fifth aspect is the heat exchanger according to any one of the first aspect to the fourth aspect, and satisfies the relationship 3 ≦ a / b ≦ 9.

In this heat exchanger, by making the structure satisfying the relationship 3 ≦ a / b, by forming the refrigerant flow path on the windward side among the refrigerant flow paths of the flat multi-hole pipe to be sufficiently large, from the surrounding fins It is possible to improve the performance of the heat exchanger in response to the amount of heat flux supplied.

Furthermore, in such a structure, in this heat exchanger, the size of the air flow direction of the relatively large refrigerant flow path on the windward side of the flat multi-hole pipe is set by satisfying the relationship of a / b ≦ 9. Comparison of the windward side of the flat multi-hole tube by ensuring that the size of the air flow direction does not become too large (by not making the size of the air flow direction excessive with respect to the length in the direction perpendicular to the air flow direction) Even in the case of a very large refrigerant flow path, it is easy to ensure a sufficient pressure resistance.

A heat exchanger according to a sixth aspect is the heat exchanger according to any one of the first aspect to the fifth aspect, and L ≧ 4 mm.

In this heat exchanger, the frost resistance can be more reliably improved by securing a sufficiently wide fin located on the windward side of the flat multi-hole pipe.

A heat exchanger according to a seventh aspect is the heat exchanger according to any one of the first aspect to the sixth aspect, wherein the width in the air flow direction of the refrigerant flow path on the windward side of the flat multi-hole pipe is flat The width of the refrigerant flow channel at the center in the air flow direction of the multi-hole pipe is 1.5 times or more and preferably 2 times or more the width in the air flow direction.

In this heat exchanger, not only the temperature difference between the refrigerant and the air tends to be large on the windward side in the air flow direction, but also the fins may be spread on the windward side compared to the flat multi-hole pipe. A large heat flux is supplied in the refrigerant flow path of Even with such a structure, it is possible to sufficiently exhibit the performance of the heat exchanger by sufficiently securing the size of the refrigerant flow path on the upwind side in the air flow direction.

It is a schematic block diagram of the air conditioning apparatus with which the heat exchanger concerning one embodiment was adopted. It is an external appearance perspective view of an outdoor unit. It is a front view of the outdoor unit (shown excluding the refrigerant circuit components other than the outdoor heat exchanger). It is a schematic perspective view of an outdoor heat exchanger. It is the elements on larger scale of the heat exchange part of FIG. It is the schematic which shows the attachment state with respect to the flat multi-hole pipe of a fin. It is a block diagram for demonstrating the refrigerant | coolant flow of an outdoor heat exchanger. It is the schematic which shows the attachment state with respect to the flat multi-hole pipe of the fin which concerns on the modification A. FIG. It is the schematic which shows the attachment state with respect to the flat multi-hole pipe of the fin concerning the modification B. FIG. It is the schematic which shows the attachment state with respect to the flat multi hole pipe of the fin which concerns on the modification C. FIG.

Hereinafter, the embodiment of the air harmony device where the outdoor heat exchanger as a heat exchanger concerning the present disclosure was adopted, and its modification are explained based on a drawing. In addition, the specific structure of the outdoor heat exchanger as a heat exchanger which concerns on this indication is not restricted to following embodiment and its modification, It can change in the range which does not deviate from the summary.

(1) Configuration of Air Conditioning Apparatus FIG. 1 is a schematic configuration view of an air conditioning apparatus 1 in which an outdoor heat exchanger 11 as a heat exchanger according to an embodiment is adopted.

The air conditioning apparatus 1 is an apparatus capable of performing cooling and heating in a room such as a building by performing a vapor compression refrigeration cycle. The air conditioner 1 mainly includes a liquid refrigerant communication pipe 4 and a gas refrigerant communication pipe 5, which connect the outdoor unit 2, the indoor units 3a and 3b, the outdoor unit 2 and the indoor units 3a and 3b, the outdoor unit 2 and And a control unit 23 configured to control components of the indoor units 3a and 3b. The vapor compression type refrigerant circuit 6 of the air conditioner 1 is configured by connecting the outdoor unit 2 and the indoor units 3 a and 3 b via the refrigerant communication pipes 4 and 5.

The outdoor unit 2 is installed outdoors (on the roof of a building, near a wall surface of a building, etc.), and constitutes a part of the refrigerant circuit 6. The outdoor unit 2 mainly includes an accumulator 7, a compressor 8, a four-way switching valve 10, an outdoor heat exchanger 11, an outdoor expansion valve 12 as an expansion mechanism, a liquid side closing valve 13, and a gas side closing valve. 14 and an outdoor fan 15 are provided. The refrigerant pipes 16 to 22 connect the devices and the valves.

The indoor units 3 a and 3 b are installed indoors (in a room, a space above the ceiling, etc.), and constitute a part of the refrigerant circuit 6. The indoor unit 3a mainly includes an indoor expansion valve 31a, an indoor heat exchanger 32a, and an indoor fan 33a. The indoor unit 3b mainly includes an indoor expansion valve 31b as an expansion mechanism, an indoor heat exchanger 32b, and an indoor fan 33b.

The refrigerant communication pipes 4 and 5 are refrigerant pipes that are constructed on site when the air conditioning apparatus 1 is installed at an installation place such as a building. One end of the liquid refrigerant communication pipe 4 is connected to the liquid side closing valve 13 of the outdoor unit 2, and the other end of the liquid refrigerant communication pipe 4 is connected to the liquid side end of the indoor expansion valves 31a and 31b of the indoor units 3a and 3b. It is done. One end of the gas refrigerant communication pipe 5 is connected to the gas side shut-off valve 14 of the outdoor unit 2, and the other end of the gas refrigerant communication pipe 5 is at the gas side end of the indoor heat exchangers 32a and 32b of the indoor units 3a and 3b. It is connected.

The control unit 23 is configured by communication connection of control boards and the like (not shown) provided on the outdoor unit 2 and the indoor units 3a and 3b. In FIG. 1, for convenience, the outdoor unit 2 and the indoor units 3a and 3b are illustrated at positions away from each other. The control unit 23 controls the constituent devices 8, 10, 12, 15, 31, 31a, 31b, 33a, 33b of the air conditioner 1 (here, the outdoor unit 2 and the indoor units 3a, 3b), that is, the air conditioner 1 It is designed to control the entire operation.

(2) Operation of Air Conditioning Device Next, the operation of the air conditioning device 1 will be described using FIG. 1. In the air conditioner 1, the compressor 8, the outdoor heat exchanger 11, the outdoor expansion valve 12, the indoor expansion valves 31a and 31b, and the indoor heat exchangers 32a and 32b sequentially flow the refrigerant, the compressor 8, the indoor heat A heating operation is performed in which the refrigerant flows in the order of the exchangers 32a and 32b, the indoor expansion valves 31a and 31b, the outdoor expansion valve 12, and the outdoor heat exchanger 11. The cooling operation and the heating operation are performed by the control unit 23.

During the cooling operation, the four-way switching valve 10 is switched to the outdoor heat radiation state (the state shown by the solid line in FIG. 1). In the refrigerant circuit 6, the low-pressure gas refrigerant in the refrigeration cycle is drawn into the compressor 8 and compressed to a high pressure in the refrigeration cycle and then discharged. The high-pressure gas refrigerant discharged from the compressor 8 is sent to the outdoor heat exchanger 11 through the four-way switching valve 10. The high-pressure gas refrigerant sent to the outdoor heat exchanger 11 exchanges heat with the outdoor air supplied as a cooling source by the outdoor fan 15 in the outdoor heat exchanger 11 functioning as a refrigerant radiator, and dissipates heat Become a high pressure liquid refrigerant. The high-pressure liquid refrigerant that has dissipated heat in the outdoor heat exchanger 11 is sent to the indoor expansion valves 31 a and 31 b through the outdoor expansion valve 12, the liquid side shut-off valve 13 and the liquid refrigerant communication pipe 4. The refrigerant sent to the indoor expansion valves 31a and 31b is depressurized to the low pressure of the refrigeration cycle by the indoor expansion valves 31a and 31b, and becomes a low pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant reduced in pressure by the indoor expansion valves 31a and 31b is sent to the indoor heat exchangers 32a and 32b. The low-pressure gas-liquid two-phase refrigerant sent to the indoor heat exchangers 32a, 32b exchanges heat with the indoor air supplied as a heating source by the indoor fans 33a, 33b in the indoor heat exchangers 32a, 32b. To evaporate. As a result, the room air is cooled, and then the room is cooled by being supplied to the room. The low-pressure gas refrigerant evaporated in the indoor heat exchangers 32a and 32b is again sucked into the compressor 8 through the gas refrigerant communication pipe 5, the gas side shut-off valve 14, the four-way switching valve 10 and the accumulator 7.

During the heating operation, the four-way switching valve 10 is switched to the outdoor evaporation state (the state shown by the broken line in FIG. 1). In the refrigerant circuit 6, the low-pressure gas refrigerant in the refrigeration cycle is drawn into the compressor 8 and compressed to a high pressure in the refrigeration cycle and then discharged. The high-pressure gas refrigerant discharged from the compressor 8 is sent to the indoor heat exchangers 32 a and 32 b through the four-way switching valve 10, the gas side shut-off valve 14 and the gas refrigerant communication pipe 5. The high-pressure gas refrigerant sent to the indoor heat exchangers 32a, 32b exchanges heat with the indoor air supplied as a cooling source by the indoor fans 33a, 33b in the indoor heat exchangers 32a, 32b to dissipate heat. It becomes a high pressure liquid refrigerant. As a result, the room air is heated and then supplied to the room to heat the room. The high-pressure liquid refrigerant that has dissipated heat by the indoor heat exchangers 32a and 32b is sent to the outdoor expansion valve 12 through the indoor expansion valves 31a and 31b, the liquid refrigerant communication pipe 4 and the liquid side shut-off valve 13. The refrigerant sent to the outdoor expansion valve 12 is decompressed to the low pressure of the refrigeration cycle by the outdoor expansion valve 12 and becomes a low pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant reduced in pressure by the outdoor expansion valve 12 is sent to the outdoor heat exchanger 11. The low-pressure gas-liquid two-phase refrigerant sent to the outdoor heat exchanger 11 exchanges heat with outdoor air supplied as a heat source by the outdoor fan 15 in the outdoor heat exchanger 11 functioning as an evaporator of the refrigerant. Go and evaporate to a low pressure gas refrigerant. The low-pressure refrigerant evaporated in the outdoor heat exchanger 11 is again sucked into the compressor 8 through the four-way switching valve 10 and the accumulator 7.

When the outdoor heat exchanger 11 functions as a refrigerant evaporator during the heating operation and the outside air temperature or the evaporation temperature of the refrigerant satisfies the predetermined operating condition, the outdoor heat exchanger 11 is frosted. May adhere. When a large amount of the frost adheres, the air supplied from the outdoor fan 15 receives excessive ventilation resistance when passing through the outdoor heat exchanger 11 to which the frost adheres, and the heat exchange efficiency is lowered. There is a risk of Therefore, when a predetermined defrost determination condition is satisfied, such as a state where the predetermined operating condition is satisfied continues for a predetermined time or more, the control unit 23 determines that the four-way switching valve 10 is in the outdoor heat dissipation state (solid line in FIG. 1). Switch to the state shown) and perform the defrost operation. In addition, when the defrost operation is performed for a predetermined time or the like, and the defrost process is completed, the control unit 23 switches the four-way switching valve 10 to the outdoor evaporation state (state shown by the broken line in FIG. 1) again Resume.

(3) Configuration of Outdoor Unit FIG. 2 is an external perspective view of the outdoor unit 2. FIG. 3 is a front view of the outdoor unit 2 (shown excluding the refrigerant circuit components other than the outdoor heat exchanger 11). FIG. 4 is a schematic perspective view of the outdoor heat exchanger 11. FIG. 5 is a partially enlarged view of the heat exchange unit 60 of FIG. FIG. 6 is a schematic view showing the attachment of the fins 64 to the flat multi-hole pipe 63. As shown in FIG. FIG. 7 is a configuration diagram for explaining the flow of the refrigerant in the outdoor heat exchanger 11.

(3-1) Overall Configuration The outdoor unit 2 is a top-blowing heat exchange unit that sucks in air from the side surface of the casing 40 and blows out air from the top surface of the casing 40. The outdoor unit 2 mainly includes a substantially rectangular box-shaped casing 40, an outdoor fan 15 as a fan, and devices 7, 8, 11 such as a compressor and an outdoor heat exchanger, a four-way switching valve, an outdoor expansion valve, etc. And refrigerant circuit components which constitute a part of the refrigerant circuit 6 including the valves 10 and 12 to 14 and the refrigerant pipes 16 to 22 and the like. In the following description, “upper”, “lower”, “left”, “right”, “front”, “back”, “front”, and “back” are shown in FIG. 2 unless otherwise specified. It means the direction when the outdoor unit 2 is viewed from the front (left oblique front in the drawing).

The casing 40 mainly includes a bottom frame 42 bridged on a pair of mounting legs 41 extending in the left-right direction, a post 43 extending vertically from a corner of the bottom frame 42, and a fan module 44 attached to the upper end of the post 43. The air inlets 40a, 40b, and 40c are formed on the side surfaces (here, the back surface and the left and right side surfaces), and the air outlet 40d is formed on the top surface.

The bottom frame 42 forms the bottom of the casing 40, and the outdoor heat exchanger 11 is provided on the bottom frame 42. Here, the outdoor heat exchanger 11 is a heat exchanger having a substantially U-shape in plan view facing the back surface and both left and right side surfaces of the casing 40, and substantially forms the back surface and both left and right side surfaces of the casing 40 .

A fan module 44 is provided on the upper side of the outdoor heat exchanger 11, and forms a front side, a rear side of the casing 40, and a portion above the columns 43 on both the left and right sides and a top surface of the casing 40. . Here, the fan module 44 is an assembly in which the outdoor fan 15 is accommodated in a substantially rectangular parallelepiped box body whose upper and lower surfaces are open. The opening of the top surface of the fan module 44 is an outlet 40 d, and the outlet 40 d is provided with an outlet grill 46. The outdoor fan 15 is disposed in the casing 40 so as to face the blowout port 40d, and is an air blower that takes in air from the suction ports 40a, 40b, 40c into the casing 40 and discharges the air from the blowout port 40d.

The front panel 45 is bridged between the columns 43 on the front side, and forms the front of the casing 40.

In the casing 40, refrigerant circuit components other than the outdoor fan 15 and the outdoor heat exchanger 11 (in FIG. 2, the accumulator 7, the compressor 8 and the refrigerant pipes 16 to 18 are shown) are also accommodated. Here, the compressor 8 and the accumulator 7 are provided on the bottom frame 42.

Thus, the outdoor unit 2 has the casing 40 in which the air inlets 40a, 40b, and 40c are formed on the side surfaces (here, the back surface and the left and right side surfaces) and the air outlet 40d on the top surface; It has the outdoor fan 15 arranged facing the blower outlet 40 d inside, and the outdoor heat exchanger 11 arranged below the outdoor fan 15 in the casing 40. And in such an upper blowing type unit configuration, since the outdoor heat exchanger 11 is disposed under the outdoor fan 15, the wind speed of the air passing through the outdoor heat exchanger 11 is different from that of the outdoor heat exchanger 11. The upper portion tends to be faster than the lower portion of the outdoor heat exchanger 11.

(3-2) Outdoor Heat Exchanger The outdoor heat exchanger 11 is a heat exchanger that performs heat exchange between the refrigerant and the outdoor air, and mainly includes the first header collecting pipe 80 and the second header collecting pipe 90, A plurality of flat multi-hole tubes 63 and a plurality of fins 64 are provided. Here, all of the first header collecting pipe 80, the second header collecting pipe 90, the flat multi-hole pipe 63 and the fins 64 are formed of aluminum or an aluminum alloy, and are mutually joined by brazing or the like.

Each of the first header collecting pipe 80 and the second header collecting pipe 90 is a vertically hollow cylindrical member. The first header collecting pipe 80 is erected on one end side of the outdoor heat exchanger 11 (here, the left front end side in FIG. 4), and the second header collecting pipe 90 is the other end of the outdoor heat exchanger 11 It is erected on the side (here, the right front end side in FIG. 4).

(4) Flat multi-hole pipe The flat multi-hole pipe 63 is a flat multi-hole pipe having a flat surface 63a on the upper and lower surfaces facing the vertical direction to be a heat transfer surface, and a large number of small passages 63b through which the refrigerant flows. The plurality of passages 63 b of the flat multi-hole tube 63 are provided side by side along the air flow direction (longitudinal direction in a sectional view of the passage 63 b). In the present embodiment, the width in the vertical direction of the flat multi-hole tube 63 is uniform, and the width in the vertical direction of the passage 63b is also uniform. The plurality of passages 63b are different in size, and are configured such that the flow passage area becomes larger as the passage is positioned on the windward side. More specifically, in the flat multi-hole tube 63 of the present embodiment, the width in the air flow direction of the passage 63b located on the windward side is configured to be the width a1, and the second and subsequent ones from the windward side. The passage 63b is configured such that the width in the air flow direction is the width a2, and the relationship of width a1> width a2 (in the present embodiment, the length Wt in the air flow direction of the flat multi-hole tube 63 The width b of the passage 63b located at the center of the same is configured to be the same as the width a2). Then, when the total value a = a1 + a2 of the widths in the air flow direction of the first and second passages 63b from the upwind side in the flat multi-hole tube 63, the relationship of 2 ≦ a / b ≦ 16 is satisfied. It is done. The relationship is more preferably a relationship that satisfies 3 ≦ a / b ≦ 9.

Further, the width a1 of the passage 63b on the upwind side of the flat multi-hole tube 63 in the air flow direction is 1.5 times or more the width b of the passage 63b in the center of the air flow direction of the flat multi-hole tube 63 in the air flow direction. Is preferable, and more preferably twice or more.

In addition, about the part which divides between each channel | path 63b of the flat multi-hole pipe | tube 63, although it does not specifically limit, it may have the same width in an air flow direction, respectively, and may be comprised.

Although the flat multi-hole pipe 63 is not particularly limited, for example, it is manufactured by extrusion molding.

A plurality of flat multi-hole tubes 63 are vertically arrayed at predetermined intervals (between the centers in the height direction: predetermined pitch Tp). Although not particularly limited, for example, the relationship between the thickness Tt in the vertical direction of the flat multi-hole tube 63 and the predetermined pitch Tp satisfies the relationship of Tp = 5 Tt to 9 Tt (more preferably Tp = 6 Tt to 8 Tt), It is preferable that the flat multi-hole pipe 63 be densely disposed in the vertical direction. Here, if the predetermined pitch Tp is too short, the space between the flat multi-hole tubes 63 is narrowed, which causes an increase in ventilation resistance and an increase in the number of flat multi-hole tubes 63 resulting in an increase in cost. It occurs. In addition, when the predetermined pitch Tp is too long, the portion of the fins 64 far from the flat multi-hole tube 63 becomes large, which causes a problem that the heat transfer efficiency of the fins 64 is reduced. Further, when the thickness Tt of the flat multi-hole tube 63 is too large, the refrigerant passage area of the passage 63b becomes too large and the flow velocity of the refrigerant in the passage 63b decreases, so that the heat transfer coefficient in the tube is obtained. Of the flat multi-hole pipe 63 in the flow direction of the air flowing to cross the flat multi-hole pipe 63 (dead water area Of the heat transfer efficiency in the fins 64 due to the increase of the thickness of the flat multi-hole tube 63 and the problem of cost increase due to the increase in thickness to secure the pressure resistance strength accompanying the enlargement of the flat multi-hole tube 63. Also, there is a problem that the amount of refrigerant increases due to the increase of the refrigerant passage area in the passage 63b. In addition, when the thickness Tt of the flat multi-hole tube 63 is too small, the refrigerant passing area of the passage 63b is reduced, so that there is a problem that the pressure loss received by the refrigerant becomes large. In consideration of the above matters, it is preferable that the relationship between the thickness Tt of the flat multi-hole tube 63 and the predetermined pitch Tp satisfies the above-mentioned relationship.

The flat multi-hole pipe 63 is connected at both ends of each passage 63 b to the first header collecting pipe 80 and the second header collecting pipe 90.

(5) Fins Fins 64 are plate-like members that extend in the air flow direction and in the vertical direction, and a plurality of fins are arranged at predetermined intervals in the plate thickness direction, and are fixed to the flat multi-hole tube 63. In the fins 64, a plurality of notches 64a which are horizontally cut from the edge on the leeward side to the windward side to the front of the windward edge are formed in the vertical direction. The shape of the notch 64a substantially matches the outer shape of the cross section of the flat multi-hole tube 63, and the flat multi-hole tube 63 is brazed and fixed to the notch 64a.

The fin 64 has a communicating portion 64x continuous in the vertical direction on the windward side further than the windward end of the flat multi-hole tube 63. Here, a distance L in the air flow direction from the wind upper end of the flat multi-hole tube 63 to the wind upper end of the communication portion 64x of the fins 64 and a length Wt of the flat multi-hole tube 63 in the air flow direction are 0.18. It is comprised so that the relationship of <= L / Wt <= 0.32 may be satisfy | filled. The relationship is more preferably a relationship satisfying 0.21 ≦ L / Wt ≦ 0.32. Further, the distance L satisfies the relationship of L ≧ 4 mm from the viewpoint of more reliably improving the frost resistance, by securing a portion of the fin 64 located on the windward side wider than the flat multi-hole tube 63 More preferable.

The fin 64 has a leeward protrusion 64 y that protrudes further leeward than the leeward end of the flat multi-hole tube 63. That is, the length in the air flow direction (the length Wf in the air flow direction of the fins 64-distance L) of the notch 64a of the fin 64 is larger than the width Wt in the air flow direction of the flat multi-hole tube 63 Is configured. Here, the distance Q in the air flow direction from the lower end of the flat multi-hole tube 63 to the lower end of the downwind protrusion 64y of the fin 64 is 2 mm or more. The upper limit of the distance Q is not particularly limited, but may be, for example, 5 mm in order to reduce the material cost of the fins 64.

(6) Other Configurations of Outdoor Heat Exchanger The outdoor heat exchanger 11 has a heat exchange unit 60 configured by fixing the fins 64 to a plurality of flat multi-hole pipes 63 aligned vertically. The heat exchange unit 60 includes an upper stage heat exchange unit 60A on the upper stage side and a lower heat exchange unit 60B on the lower stage side.

The first header collecting pipe 80 is divided into upper and lower parts by a partition plate 81 whose internal space is expanded in the horizontal direction, so that the gas side inlet / outlet communicating space corresponds to the upper heat exchanging portion 60A and the lower heat exchanging portion 60B. 80A and a liquid side inlet / outlet communicating space 80B are formed. The flat multi-hole pipe 63 constituting the corresponding upper stage heat exchange unit 60A is in communication with the gas side inlet / outlet communication space 80A. In addition, a flat multi-hole pipe 63 constituting the corresponding lower heat exchange section 60B is in communication with the liquid side inlet / outlet communication space 80B.

Further, the gas side inlet / outlet communicating space 80A of the first header collecting pipe 80 is connected with a refrigerant pipe 19 (see FIG. 1) for sending the refrigerant sent from the compressor 8 during the cooling operation to the gas side inlet / outlet communicating space 80A. .

In addition, a refrigerant pipe 20 (see FIG. 1) for transmitting the refrigerant sent from the outdoor expansion valve 12 during the heating operation to the liquid side inlet / outlet communication space 80B is connected to the liquid side inlet / outlet communication space 80B of the first header collecting pipe 80 There is.

The second header collecting pipe 90 is provided with a nozzle provided between the partition plate 92 and the partition plate 93 while the internal space of the second header collecting tube 90 is divided up and down by the partition plates 91, 92, 93 and 94 which are expanded in the horizontal direction. By being divided up and down by the plate 99, first to third upper fold return communication spaces 90A, 90B, 90C and first to third lower fold return communication spaces 90D, 90E, 90F are formed in order from the upper side. ing. The flat multi-hole pipe 63 in the corresponding upper heat exchange section 60A communicates with the first to third upper fold return communication spaces 90A, 90B, 90C, and the first to third lower fold return communication spaces 90D, 90E, 90F. , The flat multi-hole pipe 63 in the corresponding lower heat exchange section 60B is in communication. Although the third upper folding return communication space 90C and the first lower folding return communication space 90D are divided up and down by the nozzle-equipped divider 99, the nozzle 99a provided to penetrate vertically in the nozzle-equipped divider 99 is used. It communicates up and down through it. The first upper fold-back communication space 90A and the third lower fold-back communication space 90F are connected via the first connection pipe 24 connected to the second header collecting pipe 90, and the second upper fold return communication space 90B and the second lower-turn return communication space 90E are connected via a second connection pipe 25 connected to the second header collecting pipe 90.

With the above configuration, when the outdoor heat exchanger 11 functions as an evaporator of the refrigerant, the refrigerant flowing from the refrigerant pipe 20 into the liquid side inlet / outlet communication space 80B of the first header collecting pipe 80 is the liquid side inlet / outlet communication space It flows through the flat multi-hole pipe 63 of the lower heat exchange section 60B connected to 80B and flows into the first to third lower folded communication spaces 90D, 90E, 90F of the second header collecting pipe 90. The refrigerant that has flowed into the first lower fold return communication space 90D flows into the third upper fold return communication space 90C through the nozzles 99a of the dividing plate 99 with a nozzle and is connected to the third upper fold return communication space 90C. The gas flows into the gas side inlet / outlet communication space 80A of the first header collecting pipe 80 via the flat multi-hole pipe 63 of the portion 60A. The refrigerant that has flowed into the second lower-stage folded communication space 90E flows into the second upper-stage folded communication space 90B via the second connection pipe 25 and is connected to the second upper-stage folded communication space 90B. The gas flows into the gas side inlet / outlet communication space 80A of the first header collecting pipe 80 via the flat multi-hole pipe 63. The refrigerant that has flowed into the third lower turn return communication space 90F flows into the first upper turn return communication space 90A via the first connection pipe 24 and is connected to the first upper turn return communication space 90A. The gas flows into the gas side inlet / outlet communication space 80A of the first header collecting pipe 80 via the flat multi-hole pipe 63. The refrigerant joined in the gas side inlet / outlet communication space 80A of the first header collecting pipe 80 flows to the outside of the outdoor heat exchanger 11 through the refrigerant pipe 19. In addition, when the outdoor heat exchanger 11 is used as a radiator of a refrigerant | coolant, it becomes a refrigerant | coolant flow opposite to the above.

(7) Characteristics (7-1)
In the outdoor heat exchanger 11 of the present embodiment, the fin 64 has a communicating portion 64 x vertically connected on the windward side of the flat multi-hole pipe 63, and moreover, the wind is higher than the flat multi-hole pipe 63 of the fin 64. The relationship of 0.18 ≦ L / Wt for the upper part (L: distance in the air flow direction from the wind upper end of the flat multi-hole pipe to the wind upper end of the fin, Wt: length in the air flow direction of the flat multi-hole pipe) It is configured to meet the Therefore, for example, when the value of Wt is large (when the flat multi-hole pipe 63 is long), the air flow resistance received when the air passes through the outdoor heat exchanger 11 tends to be large, but the Wt is large. By increasing the area where the temperature difference with the passing air is sufficiently secured by securing the dehumidifying amount of the passing air at the windward side, the center of the air flow direction of the fins 64 to the windward side Since the amount of frost adhesion can be suppressed, it is possible to moderate the increase in ventilation resistance.

As described above, since the communication portion 64x of the frostable fins 64 is sufficiently wide in the windward portion of the outdoor heat exchanger 11 when used as an evaporator, the frost resistance is improved. Is possible. In particular, when LL4 mm, it is possible to more reliably obtain the effect of improving the frost resistance.

Therefore, it is possible to eliminate the need to frequently perform the defrosting operation performed to melt the frost adhering to the outdoor heat exchanger 11. That is, it is possible to set the defrost determination condition loose so that the defrost operation does not need to be performed frequently.

In addition, since the communication portion 64x of the fin 64 is configured to satisfy the relationship of L / Wt ≦ 0.32, the fin 64 can be reduced by reducing unnecessary portions that hardly contribute to the improvement of the frost resistance. It is possible to reduce the cost of materials.

(7-2)
In the outdoor heat exchanger 11, conventionally, the temperature difference between the air passing through the outside of the flat multi-hole pipe 63 and the refrigerant passing through the passage 63b inside the flat multi-hole pipe 63 is the windward direction in the air flow direction. Tend to be larger than downwind. For this reason, in the plurality of passages 63b provided in line in the air flow direction in the flat multi-hole pipe 63, the amount of heat exchange tends to be larger on the upwind side of the air flow than on the downwind side.

Furthermore, in the structure in which the communicating portion 64x of the fin 64 is provided on the windward side of the flat multi-hole pipe 63 in order to improve the frost resistance as described above, compared to the structure without such a communicating portion 64x, More heat flux will be supplied to the windward portion of the plurality of passages 63b of the flat multi-hole pipe 63, and the heat exchange amount in the windward passage 63b of the air flow is determined on the windward side. It tends to be larger than the passage 63b.

Even in such a structure, in the outdoor heat exchanger 11 of the present embodiment, the structure satisfying the relationship 2 ≦ a / b is satisfied (a: the first and second from the windward side of the flat multi-hole pipe 63 Total value of the width in the air flow direction of the passage 63b, b: the width of the passage 63b located at the center of the length Wt in the air flow direction of the flat multi-hole pipe 63), the windward side of the paths 63b of the flat multi-hole pipe 63 By making the passage 63b larger, it is possible to correspond to the amount of heat flux supplied from the communicating portion 64x of the windward side fin 64.

Thus, it is possible to supply a larger amount of refrigerant than the passage 63b on the leeward side in the passage 63b on the windward side where the heat flux supplied from the fins 64 is large among the passages 63b of the flat multi-hole pipe 63. Therefore, the performance of the outdoor heat exchanger 11 is achieved by reducing the flow of refrigerant without evaporation in the downwind passage 63b while suppressing the location where the evaporated refrigerant flows in the upwind passage 63b. It is possible to improve the

In addition, when it is set as the structure which satisfy | fills the relationship of 3 <= a / b, it becomes possible to show the said effect more fully.

Further, the heat flux supplied from the fins 64 is the largest in the passage 63b positioned on the windward side among the plurality of passages 63b of the flat multi-hole tube 63, but the outdoor heat exchange of this embodiment In the case 11, the width a1 of the passage 63b on the upwind side is secured at least 1.5 times the width b of the passage 63b at the center of the flat multi-hole tube 63 in the air flow direction. Therefore, the effect of improving the performance of the outdoor heat exchanger 11 can be sufficiently obtained.

(7-3)
The outdoor heat exchanger 11 of the present embodiment is configured to further satisfy the relationship of a / b ≦ 16 while adopting the above-described structure.

For this reason, it becomes possible to prevent the size of the air flow direction of the relatively large passage 63b on the windward side of the flat multi-hole tube 63 from becoming excessively large. This makes it possible to prevent the length in the air flow direction of the passage 63b on the windward side of the flat multi-hole tube 63 from becoming excessively larger than the length in the vertical direction of the passage 63b of the flat multi-hole pipe 63 . Therefore, even in the relatively large passage 63 b on the windward side of the flat multi-hole tube 63, it is possible to easily secure the pressure resistance.

In addition, when it is set as the structure which satisfy | fills the relationship of a / b <= 9, it becomes possible to show the said effect more fully.

(7-4)
In the outdoor heat exchanger 11 of the present embodiment, the fins 64 have a leeward projecting portion 64 y that protrudes further leeward than the leeward end of the flat multi-hole tube 63, and the leeward protrusion of the fins 64 The lower end of the wind at the portion 64y is further separated from the lower end of the flat multi-hole tube 63 by a distance Q (2 mm or more) on the leeward side in the air flow direction.

For this reason, even when the outdoor heat exchanger 11 is used under the condition that condensation occurs as in the case of functioning as an evaporator, the condensation water flowing from the wind lower end of each flat multi-hole pipe 63 is of fin 64 It is possible to make it difficult to supply the lower end of the wind. Thereby, even when frost adheres to the wind lower end of the fins 64, it is possible to suppress the growth of the frost.

(8) Modifications In the above embodiment, an example of the embodiment has been described, but the above embodiment is not intended to limit the present disclosure content, and is not limited to the above embodiment. The present disclosure naturally includes an aspect appropriately modified without departing from the scope of the present disclosure.

(8-1) Modification A
In the above embodiment, the leeward projecting portion 64y that protrudes further to the leeward side than the leeward end of the flat multi-hole tube 63 is provided, so that the length of the notch 64a of the fin 64 in the air flow direction ( The case where the length Wf of the fins 64 in the air flow direction−the distance L) is configured to be larger than the width Wt of the flat multi-hole tube 63 in the air flow direction has been described as an example.

However, the relationship of the width in the air flow direction between the notch 64a of the fin 64 and the flat multi-hole tube 63 is not limited to this relationship, and for example, as shown in FIG. However, it may be configured to have a leeward exposed portion 63 y that protrudes further leeward than the leeward side end of the fin 64. That is, the length in the air flow direction (the length Wf in the air flow direction of the fins 64-distance L) of the notch 64a of the fin 64 is smaller than the width Wt in the air flow direction of the flat multi-hole pipe 63 May be configured.

According to the configuration, the wind lower end of the downwind exposed portion 63y of the flat multi-hole tube 63 is positioned further downwind in the air flow direction than the wind lower end of the fin 64. A part of the tube 63 can be exposed to the downwind side. This makes it possible to prevent damage or breakage of the leeward side of the fins 64 at the time of production or transportation of the outdoor heat exchanger 11, and to protect the fins 64.

In addition, by making the leeward exposed portion 63y of the flat multi-hole tube 63 project not toward the fins 64 toward the downwind side, when the outdoor heat exchanger 11 is bent using a tool such as a roller, a tool Can be pressed against the flat multi-hole pipe 63 instead of the fins 64, and deformation and damage of the fins 64 can be suppressed. Furthermore, when the outdoor heat exchanger 11 is brazed in the furnace, the flat multi-hole pipe 63 can be brazed in a grounded state instead of the fins 64, so the aluminum fin 64 can be used during brazing. It is also possible to suppress deformation due to thermal contraction and thermal expansion of the fins 64 which may occur by contacting the floor surface of the furnace.

In addition, it is preferable that the above-described structure having the downwind exposed portion 63y is realized by a structure that further satisfies the relationship of 0.18 ≦ L / Wt ≦ 0.30 (L: wind upper end of flat multi-hole tube) Distance in the air flow direction from the top of the fins to the wind, Wt: the length of the flat multi-hole tube in the air flow direction). As described above, by configuring the portion on the windward side of the flat multi-hole tube 63 of the fins 64 to satisfy the relationship of L / Wt ≦ 0.30, an unnecessary portion that hardly contributes to the improvement of the frost resistance. By sufficiently reducing, it is possible to sufficiently reduce the material cost of the fin.

(8-2) Modification B
In the above embodiment, among the passages 63b of the flat multi-hole pipe 63, only the passage 63b located on the windward side has been described by way of example in which the width in the air flow direction is different from the other passages 63b.

However, the structure of the passage b of the flat multi-hole tube 63 for coping with many heat fluxes supplied from the fins 64 on the windward side is not limited to this, for example, as shown in FIG. The width of the second passage 63b from the windward side may be larger than the passage 63b on the windward side in the flat multi-hole pipe 63 in the direction of air flow. Even in this case, in the case of the second passage 63b from the upwind side, it is possible to process a large amount of heat flux supplied from the communicating portion 64x of the fin 64.

Further, in the case where the flat multi-hole pipe 63 is manufactured by extrusion molding, the flow-side end of the flat multi-hole pipe 63 in the air flow direction is the passage 63 b which is positioned at the wind-up end of the plurality of paths 63 b. Among the plurality of passages 63b, the windward end of the plurality of passages 63b can be produced by individual differences in the thickness of the wall surface of the part or by making the windward end of the flat multi-hole tube 63 in the air flow direction rounded. There is a possibility that the passage 63b which is to be located at the end of However, even if there is such an arrangement, the width in the air flow direction is designed to be large in at least one of the passage 63 b on the upwind side and the passage 63 b from the upwind side. Even if the passage 63b located on the windward side is unintentionally reduced, it is possible to process a large amount of heat flux supplied from the communicating portion 64x of the fin 64.

(8-3) Modification C
Further, as a structure of the passage b of the flat multi-hole pipe 63 for coping with many heat fluxes supplied from the fins 64 on the wind side, for example, as shown in FIG. The width of the passage 63b in the air flow direction may be gradually reduced toward the downwind side. Even in this case, it is possible to process many heat fluxes supplied from the communicating portion 64x of the fin 64.

In the heat exchanger having the structure according to the above embodiment and modification A, Wf: Length in the air flow direction of the fins 64, L: distance in the air flow direction from the wind upper end of the flat multi-hole pipe to the wind upper end of the fins , Wt: Length in the air flow direction of the flat multi-hole pipe, a: total value of the widths in the air flow direction of the first and second passages 63b from the windward side in the flat multi-hole pipe 63, b: flat multi-hole pipe The analysis results in the case where each value of the width of the passage 63b located at the center of the length Wt in the air flow direction 63 is changed are shown in Table 1 as Examples 1 to 12.

In addition, Examples 1, 2, 5, 6, 9, 10 correspond to the structure in which the fin 64 in the above embodiment has the leeward protruding portion 64y. Moreover, Example 3, 4, 7, 8, 11, 12 corresponds to the structure in which the flat multi-hole pipe 63 in the modification A has the downwind exposure part 63y.

In any of the embodiments, the width of the passage 63b in the flat multi-hole tube 63 in the air flow direction is different from that of the other passages only in the passage 63b on the upwind side.

The heat flux on the surface of the windward end of the flat multi-hole tube 63, the heat flux on the surface of the central part of the flat multi-hole tube 63, and the leeward of the flat multi-hole tube 63 are shown in Table 1 for q1, q2 and q3. The average value of the quantity of heat flux in the surface of a side end is shown, respectively. In addition, these heat flux has shown the analysis value by computer analysis based on computational fluid dynamics (CFD: computational fluid dynamics).

Moreover, about the heat exchanger which has a structure which concerns on the said embodiment, the analysis result which examined the difference in the frosting time T at the time of changing the value of L is tabulated as Example 13, 14 and Comparative Examples 1-3. Shown in 2.

In Examples 13, 14 and Comparative Examples 1 to 3, the fin 64 in the above embodiment corresponds to the structure having the leeward protruding portion 64y, Wt is fixed to 19 mm, Wf is L + Wt + 2 mm, a = Only the passage 63b on the upwind side was made common as a structure different from the other passages while setting 1 mm and b = 0.5 mm.

The frosting time T is such that when the heat exchanger is used as an evaporator under a common predetermined condition, the pressure loss to which the air flow supplied to the heat exchanger is subjected rises by 200 Pa due to the increase in the amount of frost formation. It was the time required.

As shown in Examples 13 and 14 above, it is confirmed that the frost formation time T can be increased by increasing the value of L, and it is possible to delay the increase of the ventilation resistance due to the adhesion of the frost. The As shown in Comparative Examples 2 and 3, when the value of L is too large relative to Wt, the portion contributing to the improvement of the frost resistance among the portions corresponding to L of the fins may be increased. It has also been confirmed that it is impossible to do so and merely increases the material cost of the fins.

While the embodiments of the present disclosure have been described above, it will be understood that various changes in form and detail can be made without departing from the spirit and scope of the present disclosure as set forth in the claims. .

1 air conditioner 2 outdoor unit 11 outdoor heat exchanger (heat exchanger)
63 Flat multi-hole pipe 63a Flat surface 63b Passageway (refrigerant flow path)
63 y downwind exposed portion 64 fin 64 a notched portion (notched portion)
64x communication part (part connected up and down on windward side)
64y Downwind projection a Total value a1 Width (width of the most upstream refrigerant flow channel in the air flow direction)
a2 Width b Width (width in the air flow direction of the refrigerant channel at the center of the flat multi-hole air flow direction of the flat multi-hole pipe)
L Distance in the air flow direction from the wind upper end of the flat multi-hole pipe to the wind upper end of the fin Wt Length in the air flow direction of the flat multi-hole pipe

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-139282

Claims (7)

A flat multi-hole pipe (63) having a plurality of refrigerant flow paths (63b) aligned in the air flow direction;
The flat multi-hole tube is inserted and fixed at a point (64a) which is cut away from the downwind side to the upwind side in the air flow direction, and the part (64x) vertically connected on the upwind side of the flat multi-hole pipe With fins (64),
Equipped with
L: distance in the air flow direction from the wind upper end of the flat multi-hole tube to the wind upper end of the fin,
Wt: Length of the flat multi-hole tube in the air flow direction,
a: A total value of the widths in the air flow direction of the first and second refrigerant channels from the windward side in the flat multi-hole pipe,
b: the width in the air flow direction of the refrigerant channel at the center in the air flow direction in the flat multi-hole pipe,
0.18 ≦ L / Wt ≦ 0.32 when
And
2 ≦ a / b ≦ 16
Meet the relationship of
Heat exchanger (11). Satisfy the relationship of 0.21 ≦ L / Wt ≦ 0.32,
The wind lower end of the fin is located further downwind in the air flow direction than the wind lower end of the flat multi-hole tube.
The heat exchanger according to claim 1. The wind lower end of the fin is located further than 2 mm away from the wind lower end of the flat multi-hole tube on the leeward side.
The heat exchanger according to claim 2. Satisfy the relationship of 0.18 ≦ L / Wt ≦ 0.30,
The lower end of the flat multi-hole tube is located further downstream in the air flow direction than the lower end of the fin.
The heat exchanger according to claim 1. Satisfy the relationship 3 ≦ a / b ≦ 9,
The heat exchanger according to any one of claims 1 to 4. L ≧ 4 mm,
The heat exchanger according to any one of claims 1 to 5. The width (a1) in the air flow direction of the refrigerant flow path on the windward side of the flat multi-hole pipe is the width (b) in the air flow direction of the refrigerant flow path in the center of the air flow direction of the flat multi-hole pipe More than 1.5 times,
The heat exchanger according to any one of claims 1 to 6.

Images