Heat exchanger and air conditioning device

Abstract

The heat exchanger comprises a number of flat tubes through which a refrigerant flows, and a number of fins that are arranged between the flat tubes to transfer heat from the refrigerant flowing through the flat tubes. The fins have a planar portion with an opening formed in part of it, and louvers that open and close the openings in the planar portion, and a louver removal space is formed in the planar portion by cutting out a position connected to the end of the louver.

Description

[Technical field]

[0001] The present disclosure relates to a heat exchanger and an air conditioner that include flat tubes and fins. [Background technology]

[0002] Conventionally, heat exchangers including flat tubes and fins have been known. Patent Document 1 discloses a heat exchanger including a plurality of flat tubes and a corrugated fin provided with a plurality of louvers. Patent Document 1 aims to improve the heat transfer performance and fin strength by forming a plurality of slit drainage holes close to each other in a corrugated fin heat exchanger, while smoothly draining condensed water that adheres to the surface of the fin when used as an evaporator. Patent Document 1 also aims to improve the heat exchange efficiency by improving drainage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-153540 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the heat exchanger disclosed in Patent Document 1, where corrugated fins are provided across multiple rows of flat tubes, the ends of the louver group are cut and raised directly from the plane of the fin to form the inclined portion of the louver. Therefore, liquid droplets that flow down along the inclined portion of the louver accumulate on the flat surface. Even if the ends of the louver group do not directly form the inclined portion of the louver from the plane of the fin, condensed water accumulates because the gap between the flat surface and the louvers is narrow.

[0005] The present disclosure has been made to solve the above-mentioned problems, and provides a heat exchanger and an air conditioner that suppress water accumulation at the ends of louvers. [Means for solving the problem]

[0006] The heat exchanger according to the present disclosure includes a plurality of flat tubes through which a refrigerant flows, and a plurality of fins provided between the flat tubes to transfer heat of the refrigerant flowing through the flat tubes, the fins having a planar portion with an opening formed in a portion thereof and louvers for opening and closing the opening in the planar portion, and a louver-removed space is formed in the opening by cutting out a portion of an end portion of the flat tube in the major axis direction at the opening, the portion being shifted in either direction in the minor axis direction of the flat tube. The louver-removed space is connected to the opening at one part in the longitudinal direction of the flat tube, and connected to the flat portion at the other part in the longitudinal direction of the flat tube. . Effect of the Invention

[0007] According to the present disclosure, a louver removal space is formed by cutting out the flat surface at a position connected to the end of the louver. Therefore, water that accumulates at the end of the louver is discharged through the louver removal space. Therefore, it is possible to prevent water from accumulating at the end of the louver. [Brief description of the drawings]

[0008] [Figure 1] 1 is a circuit diagram showing an air conditioner according to a first embodiment. [Diagram 2] FIG. 1 is a front view showing a heat exchanger according to a first embodiment. [Diagram 3] FIG. 1 is a perspective view showing a heat exchanger according to a first embodiment. [Figure 4] FIG. 2 is a schematic diagram showing a fin according to the first embodiment. [Diagram 5] FIG. 2 is a top view showing the heat exchanger according to the first embodiment. [Figure 6] FIG. 2 is a side view showing the heat exchanger according to the first embodiment. [Figure 7] FIG. 4 is a top view showing a heat exchanger according to a modified example of the first embodiment. [Figure 8] FIG. 11 is a perspective view showing a heat exchanger according to a second embodiment. [Figure 9] FIG. 11 is a top view showing a heat exchanger according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the heat exchanger and air conditioning device of the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to the embodiment described below. In addition, in the following drawings, including FIG. 1, the relationship of the sizes of the components may differ from the actual one. In addition, in the following description, terms indicating directions are appropriately used to facilitate understanding of the present disclosure, but these terms are for explaining the present disclosure and do not limit the present disclosure. Examples of terms indicating directions include "up", "down", "right", "left", "front" or "rear". Note that in some drawings, hatching in cross-sectional views is partially omitted.

[0010] Embodiment 1 Fig. 1 is a circuit diagram showing an air conditioner 1 according to embodiment 1. As shown in Fig. 1, the air conditioner 1 is a device that adjusts air in an indoor space, and includes an outdoor unit 2 and an indoor unit 3 connected to the outdoor unit 2. The outdoor unit 2 is provided with a compressor 6, a flow path switching device 7, a heat exchanger 8, an outdoor blower 9, and an expansion section 10. The indoor unit 3 is provided with an indoor heat exchanger 11 and an indoor blower 12.

[0011] A compressor 6, a flow path switching device 7, a heat exchanger 8, an expansion section 10, and an indoor heat exchanger 11 are connected by a refrigerant pipe 5 to form a refrigerant circuit 4 through which a refrigerant, which is a working gas, flows. The compressor 6 draws in a refrigerant in a low-temperature and low-pressure state, compresses the drawn-in refrigerant, and discharges it as a refrigerant in a high-temperature and high-pressure state. The flow path switching device 7 switches the direction in which the refrigerant flows in the refrigerant circuit 4, and is, for example, a four-way valve. The heat exchanger 8 exchanges heat between, for example, outdoor air and the refrigerant. The heat exchanger 8 acts as a condenser during cooling operation, and acts as an evaporator during heating operation.

[0012] The outdoor blower 9 is a device that sends outdoor air to the heat exchanger 8. The expansion section 10 is a pressure reducing valve or an expansion valve that reduces the pressure of the refrigerant and expands it. The expansion section 10 is, for example, an electronic expansion valve whose opening degree is adjustable. The indoor heat exchanger 11 is, for example, a device that exchanges heat between indoor air and the refrigerant. The indoor heat exchanger 11 acts as an evaporator during cooling operation and as a condenser during heating operation. The indoor blower 12 is a device that sends indoor air to the indoor heat exchanger 11.

[0013] (Operation mode, cooling operation) Next, the operation modes of the air conditioner 1 will be described. First, the cooling operation will be described. In the cooling operation, the refrigerant sucked into the compressor 6 is compressed by the compressor 6 and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 6 passes through the flow switching device 7 and flows into the heat exchanger 8 acting as a condenser, where it is heat exchanged with the outdoor air sent by the outdoor blower 9, condensing and liquefying. The condensed liquid state refrigerant flows into the expansion section 10, where it is expanded and decompressed to become a low-temperature, low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant then flows into the indoor heat exchanger 11 acting as an evaporator, where it is heat exchanged with the indoor air sent by the indoor blower 12, evaporating and gasifying. At this time, the indoor air is cooled, and cooling is performed in the room. The evaporated refrigerant in a low-temperature, low-pressure gas state passes through the flow switching device 7 and is sucked into the compressor 6.

[0014] (Operation mode, heating operation) Next, the heating operation will be described. In the heating operation, the refrigerant sucked into the compressor 6 is compressed by the compressor 6 and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 6 passes through the flow path switching device 7 and flows into the indoor heat exchanger 11 acting as a condenser, where it exchanges heat with the indoor air sent by the indoor blower 12, condenses and liquefies. At this time, the indoor air is warmed, and heating is performed in the room. The condensed liquid state refrigerant flows into the expansion section 10, where it expands and is decompressed to become a low-temperature, low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant then flows into the heat exchanger 8 acting as an evaporator, where it exchanges heat with the outdoor air sent by the outdoor blower 9, evaporates and gasifies. The evaporated low-temperature, low-pressure gas state refrigerant passes through the flow path switching device 7 and is sucked into the compressor 6.

[0015] It should be noted that the air conditioner 1 does not necessarily have to have the flow path switching device 7. In this case, the air conditioner 1 becomes a dedicated cooling machine or a dedicated heating machine.

[0016] 2 is a front view showing the heat exchanger 8 according to the first embodiment. Next, the heat exchanger 8 will be described in detail. As shown in FIG. 2, the heat exchanger 8 is, for example, a parallel flow type heat exchanger. The heat exchanger 8 may be a fin tube type heat exchanger. The heat exchanger 8 includes flat tubes 20, fins 30, and a header 40.

[0017] (Flat tube 20) The flat tubes 20 are tubes through which a refrigerant flows, and are arranged in a plurality of rows, and are made of, for example, aluminum or an aluminum alloy. The plurality of flat tubes 20 are arranged at intervals so that their longitudinal axes face each other, and fins 30 are provided between the flat tubes 20. The flat tubes 20 may also be made of a clad material having aluminum as a core material. The flat tubes 20 have, for example, a plurality of flow paths formed in a line through which the refrigerant flows. The flat tubes 20 extend with the height direction as the longitudinal direction.

[0018] (Fin 30) The fins 30 are members that transfer heat of the refrigerant flowing through the flat tubes 20, and are, for example, corrugated fins that are bent and arranged between the flat tubes 20. The fins 30 have inclined surfaces that are inclined with respect to the horizontal direction, and are alternately folded. That is, the fins 30 can be said to be strip-shaped members that are alternately folded and arranged in a plurality in the height direction. Between the fins 30 and the flat tubes 20, there are ventilation passages 31 through which air flows. The fins 30 are made of, for example, aluminum. The fins 30 may be plate fins.

[0019] (Header 40) The header 40 is made of, for example, aluminum, through which the refrigerant flows and which divides the refrigerant into the flat tubes 20 connected thereto. In this way, the header 40 may be made of the same material as the fins 30 and the flat tubes 20, or may be made of a different material. The header 40 has a header 40 that connects one end of the flat tubes 20 and a header 40 that connects the other end of the flat tubes 20. The inside of the header 40 may be configured such that the space through which the refrigerant flows is divided by one or more partitions. A refrigerant pipe 5 is connected to one of the headers 40, and the header 40 is connected to the flow path switching device 7 by the refrigerant pipe 5. A refrigerant pipe 5 is connected to the other header 40, and the header 40 is connected to the expansion section 10 by the refrigerant pipe 5. The header 40 may be made of the same material as the flat tubes 20.

[0020] (Plane part 32) Fig. 3 is a perspective view showing the heat exchanger 8 according to the first embodiment. As shown in Fig. 3, the fin 30 has a flat portion 32 and a plurality of louvers 33. The flat portion 32 is a plate-like member extending at an angle along the longitudinal direction of the flat tubes 20. The flat portion 32 has a rectangular opening 32a extending along the longitudinal direction of the flat tubes 20 in a part of the central portion excluding both end portions adjacent to the flat tubes 20.

[0021] (Luver 33) FIG. 4 is a schematic diagram showing the fin 30 according to the first embodiment. As shown in FIG. 4, the louvers 33 open and close the openings 32a formed in the planar portion 32. A plurality of the louvers 33 are provided for one opening 32a. The louvers 33 are formed by cutting and raising a part of the planar portion 32, and are inclined in a side view. In a side view, the louvers 33 have one end higher than the planar portion 32 and the other end lower than the planar portion 32 with respect to the height of the planar portion 32. In the first embodiment, there is no part that is connected to the planar portion 32 and becomes the inclined portion of the louvers 33 as it is. This part is a louver removal space 34. If there is no louver removal space 34, there will be a part that is connected to the planar portion 32 and becomes the louvers 33 as it is. The length of this louver 33 is half that of the other louvers 33 in order to align the position in the height direction (see the dashed line in FIG. 4). The plurality of louvers 33 that open and close one opening 32a is called a louver group 33a.

[0022] (Louver removed space 34) A louver-removed space 34 is formed in the flat portion 32. As shown in FIG. 3, the louver-removed space 34 is formed by cutting out the flat portion 32 at positions connected to the ends of the multiple louvers 33. FIG. 3 illustrates an example in which the louver-removed space 34 is offset in the short axis direction of the flat tube 20 with respect to the opening 32a formed in the flat portion 32, but the space may not be offset, or the offset may be different. As shown in FIG. 4, the louver-removed space 34 is formed at the end of the long axis direction of the flat tube 20 at the opening 32a formed in the flat portion 32. That is, the louver-removed space 34 can be said to be a space in which a portion where the louvers 33 are provided, which is originally half the length (see the dashed line in FIG. 4), is cut out.

[0023] FIG. 5 is a top view showing the heat exchanger 8 according to the first embodiment. Next, the position of the louver-removed space 34 in the fins 30 bent adjacent to each other in the height direction will be described. In FIG. 5, the fin 30 on the left side is the upper fin 30, the fin 30 in the center is the middle fin 30, and the fin 30 on the right side is the lower fin 30. In addition, in FIG. 5, the upper side is the windward side, and the lower side is the leeward side. As shown in FIG. 5, the louver-removed spaces 34 are offset in the height direction. In FIG. 5, the lengths of the flat tubes 20 in the louver-removed spaces 34 in the short axis direction are the same, but they may be different. In addition, the offset of the louver-removed spaces 34 may be periodic or non-periodic. If the louver-removed spaces 34 are periodic, the manufacturing process is simplified.

[0024] Fig. 6 is a side view showing the heat exchanger 8 according to the first embodiment. When the louver-removed spaces 34 are misaligned in the height direction, the water adhering to the fins 30 falls downward without staying in one place, as shown in Fig. 6. This makes it difficult for the droplets 50 to stay on the fins 30. Note that drainage is further improved when the louver-removed spaces 34 reach the bottom of the inclined portion of the fin 30, which is the portion where the fin 30 and the flat tubes 20 are joined.

[0025] (Modification) Fig. 7 is a top view showing a heat exchanger 8 according to a modified example of the first embodiment. In Fig. 7, the length of the fins 30 in the longitudinal direction is considerably longer than the length of the flat tubes 20 in the longitudinal direction, and the fins 30 protrude outward from both ends of the flat tubes 20. As shown in Fig. 7, one of the two louver-removed spaces 34 is formed in the fins 30 protruding outward from both ends of the flat tubes 20. In this way, the louver-removed space 34 does not have to face the flat tubes 20.

[0026] According to the first embodiment, a louver removal space 34 is formed by cutting out a position in the planar portion 32 that is connected to the end of the louver 33. Therefore, water that accumulates at the end of the louver 33 is discharged through the louver removal space 34. Therefore, it is possible to prevent water from accumulating at the end of the louver 33.

[0027] Furthermore, the flat tubes 20 extend with the height direction as the longitudinal direction, and the fins 30 are arranged in a plurality of rows in the height direction, with the louver removal spaces 34 of the fins 30 arranged in the height direction being offset from one another in the height direction. For this reason, liquid droplets adhering to the fins 30 fall through the louver removal space 34 located above, strike the flat surface portion 32 located below, flow along the inclined flat surface portion 32, and further fall through the louver removal space 34. That is, liquid droplets are unlikely to remain on the fins 30.

[0028] Embodiment 2 8 is a perspective view showing a heat exchanger 8 according to embodiment 2. In embodiment 2, the dimensions of the louver removed space 34 are specified. In embodiment 2, the same reference numerals are used to designate parts common to embodiment 1, and descriptions thereof are omitted, and differences from embodiment 1 will be mainly described.

[0029] As shown in FIG. 8, the width T of the flat tubes 20 in the long axis direction in the louver-removed space 34 is 1 / 3 to 2 / 3 of the width W of the louvers 33. This allows for improved drainage without impairing the heat exchange capacity. In other words, it is possible to achieve both heat exchange capacity and drainage. It is further preferable that the width T of the flat tubes 20 in the long axis direction in the louver-removed space 34 is 1 / 2 of the width W of the louvers 33. This simplifies the manufacturing process because it is only necessary to remove the portion where the louvers 33 are provided, which is half the original length.

[0030] Embodiment 3 9 is a top view showing a heat exchanger 8 according to embodiment 3. Embodiment 3 differs from embodiments 1 and 2 in that slits 35 are formed in the fins 30. In embodiment 3, parts common to embodiments 1 and 2 are denoted by the same reference numerals and description thereof is omitted, and the following description will focus on the differences from embodiments 1 and 2.

[0031] As shown in FIG. 9, the fin 30 is formed with slits 35 for draining water accumulated in the planar portion 32. The slits 35 are not adjacent to the louvers 33. FIG. 9 illustrates a case where a plurality of slits 35 are formed and, similar to the louver removal space 34, the slits 35 are offset from each other in the height direction. It is to be noted that a single slit 35 may be formed, or the slits 35 may be aligned in the height direction. In this way, in the third embodiment, the slits 35 are formed in addition to the louver removal space 34, and therefore the drainage performance can be further improved. [Explanation of symbols]

[0032] 1 air conditioning unit, 2 outdoor unit, 3 indoor unit, 4 refrigerant circuit, 5 refrigerant piping, 6 compressor, 7 flow path switching device, 8 heat exchanger, 9 outdoor blower, 10 expansion section, 11 indoor heat exchanger, 12 indoor blower, 20 flat tube, 30 fin, 31 ventilation duct, 32 flat section, 32a opening, 33 louver, 33a louver group, 34 louver removal space, 35 slit, 40 header, 50 droplets.

Claims

1. A plurality of flat tubes through which a refrigerant flows; A plurality of fins are provided between the flat tubes to transfer heat of a refrigerant flowing through the flat tubes, The fin is A planar portion having an opening formed in a portion thereof; a louver for opening and closing the opening in the planar portion, A louver-removed space is formed in the opening by cutting out a portion of an end portion of the flat tube in the major axis direction, the portion being shifted in either direction of the minor axis direction of the flat tube, The louver-removed space is formed such that one part of the flat tube in the longitudinal direction is connected to the opening, and the other part of the flat tube in the longitudinal direction is connected to the flat portion. heat exchanger.

2. A plurality of flat tubes through which a refrigerant flows; A plurality of fins are provided between the flat tubes to transfer heat of a refrigerant flowing through the flat tubes, The fin is A planar portion having an opening formed in a portion thereof; a louver for opening and closing the opening in the planar portion, A louver removal space is formed in the planar portion by cutting out a position connected to an end of the louver, The louver removed space is The end of the louver is offset in the short axis direction of the flat tube, The flat tube extends with the height direction as the longitudinal direction, The fins are arranged in a plurality of rows in the height direction, The louver-removed spaces of the fins arranged in the height direction are offset from each other in the height direction. heat exchanger.

3. The width of the flat tube in the longitudinal direction in the louver-removed space is 1 / 3 to 2 / 3 of the width of the louver 3. The heat exchanger according to claim 1 or 2.

4. The fins include: The flat surface has a slit for draining water that accumulates therein.

3. The heat exchanger according to claim 1 or 2.

5. The flat tube extends with the height direction as the longitudinal direction, The fins are arranged in a plurality of rows in the height direction, The slits of the fins arranged in the height direction are offset from each other in the height direction.

5. The heat exchanger according to claim 4.

6. The heat exchanger according to claim 1 or 2. An air conditioning device comprising:

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