Plate-fin stacked heat exchanger and refrigeration system using same

Abstract

To provide a plate fin lamination type heat exchanger light in weight and suppressing a water drop splashing phenomenon, and a refrigeration system using the same and having high reliability.SOLUTION: A heat exchanger is structured by laminating a plurality of plate fins 2a having header flow passes A11, B12 and a heat transfer flow pass 8 connecting the header flow passes. The plate fins 2a are structured by bonding two plates. A first plate 9 as one of the plates is in a flat plate state holding a strip shape. A second plate 10 as the other of them includes a heat transfer flow pass forming part 14 forming the heat transfer flow pass in a space between the first plate 9 and the second plate, and flat plate state end plate parts 15a, 15b provided to both longitudinal ends of the heat transfer flow pass forming part 14, and is structured by cutting 16 at least the plate both edge parts of the heat transfer flow pass forming part 14. Such structures above result in achieving weight reduction of the whole of the heat exchanger and also suppressing water droplet splash from a plate fin edge to improve reliability of the heat exchanger.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a plate fin stack type heat exchanger and a refrigeration system using the same. [Background technology]

[0002] Patent Document 1 discloses a plate fin stack type heat exchanger. This plate fin stack type heat exchanger is constructed by stacking a plurality of plate fins each having a header flow path and a heat transfer flow path. The plate fins are constructed by brazing a pair of plates facing each other, and a first fluid such as a refrigerant that flows from one header flow path into a heat transfer flow path flows to the other header flow path which serves as an outlet, and heat is exchanged between the first fluid flowing in the heat transfer flow path and a second fluid such as air flowing in the gaps between the plate fins. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-66532 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a lightweight and highly reliable plate fin stacked heat exchanger and a refrigeration system using the same, which solves the problems arising from the above-described conventional plate fin configuration. [Means for solving the problem]

[0005] The plate fin stacked type heat exchanger of the present disclosure is a heat exchanger constructed by stacking a plurality of plate fins, each of which has a pair of header flow paths and a heat transfer flow path connecting the header flow paths, and the plate fins are constructed by joining two plates, one of the two plates, a first plate, is in a flat state maintaining a rectangular shape, and the other, a second plate, has a heat transfer flow path forming portion that forms a heat transfer flow path between itself and the first plate, and flat end plate portions provided on both longitudinal ends of the heat transfer flow path forming portion, and is configured such that at least both plate edge portions of the heat transfer flow path forming portion are cut away. Effect of the Invention

[0006] In the plate fin stacked heat exchanger of the present disclosure, the above configuration reduces the flat portion of one of the plates that constitute the plate fins by removing at least both end edge portions of the heat transfer flow path forming portion, thereby making it possible to reduce the weight of the entire heat exchanger, and since the plate thickness of the plate fin edge is only the plate thickness of one plate, it is thin, thereby suppressing the growth of water droplets that condense and adhere to the plate fin edge on the side where the second fluid flows in, and suppresses the water splash phenomenon in which large water droplets are blown away by a downstream blower fan, etc. It is also possible to provide a highly reliable refrigeration system that reduces damage caused by water splashing from the heat exchanger. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing an external appearance of a plate fin stack type heat exchanger according to a first embodiment; [Diagram 2] FIG. 2 is a perspective view showing a plate fin stack of the plate fin stack type heat exchanger of the same embodiment; [Diagram 3] FIG. 2 is an exploded perspective view showing the plate fin stacking state of the plate fin stack type heat exchanger of the same embodiment. [Figure 4] FIG. 2 is an enlarged perspective view showing a main part of the plate fin stack of the plate fin stack type heat exchanger of the same embodiment; [Diagram 5] Cross section AA of Figure 2 [Figure 6] Cross section B-B of Figure 2 [Figure 7A] FIG. 13 is an explanatory diagram showing the condensation state of the plate fin stacked heat exchanger of the same embodiment. [Figure 7B] FIG. 1 is an explanatory diagram showing the air flow in the plate fin stacked heat exchanger. [Figure 8] FIG. 11 is a perspective view of a plate fin in another example of the plate fin stack type heat exchanger of the same embodiment; [Figure 9] FIG. 4 is a plan view of plate fins in still another example of the plate fin stacked heat exchanger of the same embodiment; [Figure 10] FIG. 1 is a refrigeration cycle diagram of an air conditioner as an example of a refrigeration system configured using the plate fin stacked type heat exchanger of the first embodiment. [Figure 11] FIG. 3 is a cross-sectional view showing an indoor unit of the air conditioner. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (The knowledge and other information that formed the basis of this disclosure) At the time when the inventors came up with the present disclosure, the plate fins of the plate fin stacked type heat exchanger were configured by brazing two plates, each having an opening for a header flow path and a groove for a heat transfer flow path, facing each other. Therefore, there was a problem that the plate fins were in the form of two overlapping plates, which made the plate thickness thick and made the heat exchanger heavy as a whole. In addition, because the plate fins were thick, when the heat exchanger was used as a cooling heat source, condensation water adhered to the edge of the plate fins, which grew into large droplets that could fly up to the ventilation fan or the like installed downstream, impairing the reliability of the equipment equipped with the heat exchanger.

[0009] The present inventors have come to constitute the subject of the present disclosure in order to solve such problems. Therefore, the present disclosure provides a plate-fin stacked heat exchanger that is lightweight and suppresses the water splash phenomenon, and a refrigeration system using the same.

[0010] Hereinafter, the embodiments will be described in detail with reference to the drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming more redundant than necessary and to facilitate understanding by those skilled in the art.

[0011] It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0012] (Embodiment 1) Hereinafter, the first embodiment will be described with reference to FIGS.

[0013] [1-1. Configuration] 1, the heat exchanger 1 of this embodiment is configured by integrally joining end plates 3a, 3b having approximately the same shape in a plan view to both sides of a plate fin stack 2 consisting of rectangular plate fins 2a. One end of the plate fin stack 2 has a tube A4 that serves as an inlet when used as a condenser and an outlet when used as an evaporator, and a tube B5 that serves the opposite purpose.

[0014] The end plates 3a, 3b on either side of the plate fin stack 2 are joined by brazing in a manner that sandwiches the plate fin stack 2, and both longitudinal ends are connected and fixed by fastening means 7, thereby maintaining the rigidity of the heat exchanger.

[0015] 2, the plate fin stack 2 is formed by stacking a large number of plate fins 2a each having a pair of header flow paths A11, B12 to which tubes A4 and B5 are connected, and a heat transfer flow path 8 through which a first fluid such as a refrigerant (hereinafter referred to as refrigerant) flows, to form a stacking gap between each pair of plate fins 2a through which a second fluid such as air (hereinafter referred to as air) flows. Heat is exchanged between the refrigerant flowing through the heat transfer flow paths 8 provided in the plate fins 2a and the air flowing through the stacking gaps between the plate fins 2a.

[0016] Next, the structure of the plate fins 2a will be described in detail with reference to FIG.

[0017] The plate fins 2a of this embodiment are configured by brazing a first plate 9 having a rectangular shape and a second plate 10 having a rectangular shape with a part thereof cut away.

[0018] The first plate 9 has header flow paths A11, B12 to which the tubes A4 and B5 are connected on one end side, and a groove portion 13 that serves as a heat transfer flow path 8 connecting the header flow paths A11, B12, and is maintained in a flat state.

[0019] The second plate 10, in addition to the header flow paths A11 and B12 as in the first plate 9, comprises a heat transfer flow path forming portion 14 having a groove portion forming a heat transfer flow path 8 between the groove portion 13 of the first plate 9 and flat end plate portions 15a and 15b provided at both ends in the longitudinal direction of the heat transfer flow path forming portion 14, and is configured by cutting 16 a part of the flat plate portion, in this example, at least the flat plate portion of both longitudinal edge portions of the heat transfer flow path forming portion 14. Fin stacking interval forming convex portions 17 that abut against the back surface of the first plate 9 to form an interval for air circulation between the plate fins 2a are cut and raised on the remaining flat plate portions at both longitudinal edges. The rectangular first plate 9 and the second plate 10 are brazed together facing each other to form the plate fins 2a having the header flow paths A11 and B12 and the heat transfer flow path 8.

[0020] The plate fins 2a and the end plates 3a, 3b are made of aluminum or an aluminum alloy.

[0021] [1-2. Operation] Next, the operation and effect of the plate fin laminated type heat exchanger constructed as above will be described by taking as an example the case where it is used as a heat exchanger for an air conditioner.

[0022] When the heat exchanger 1 of this embodiment is used under condensing conditions, for example, the gas-phase refrigerant flows from tube A4 into the header flow passage A11 on the inlet side of the plate fin stack 2. The gas-phase refrigerant that flows into the header flow passage A11 turns around and flows through the heat transfer flow passages 8 of each plate fin 2a, and flows out of tube B5 into the refrigerant circuit of the refrigeration system via the header flow passage B12 on the outlet side. Then, while flowing through the heat transfer flow passage 8, the refrigerant exchanges heat with air passing through the gaps between the plate fins of the plate fin stack 2, and the gas-phase refrigerant gradually becomes liquid and flows out of the header flow passage B12.

[0023] Here, the plate fins 2a of the plate fin stack 2 are formed by brazing a first plate 9 and a second plate 10, and the second plate 10 has flat plate portions on both longitudinal edges of the heat transfer flow path forming portion 14 cut out 16, reducing the weight by the amount of the flat plate portions cut out 16. This makes it possible to significantly reduce the weight of the entire heat exchanger.

[0024] Furthermore, when a heat exchanger with the above configuration is used under condensing conditions, i.e., when used as a cooling source, the edges of the plate fins 2a with which air passing through the gaps between the plate fins collides are thin, being only the thickness of the first plate 9, as shown in Y of Fig. 4 and the right diagram of Fig. 7A (the left diagram shows the edge of a conventional two-layer plate fin). Therefore, even if condensed water Z adheres to the edges of the plate fins 2a, the growth of the condensed water is suppressed, and the phenomenon of water splashing, in which the condensed water forms large droplets and is blown away by a downstream blower fan or the like, can be suppressed.

[0025] In addition, the stacking interval of the plate fins 2a without the flat portion of the second plate 10, i.e., the flow path region portion X (see FIG. 2) where the heat transfer flow path forming portion 14 is formed, is wider than when only the thickness of the first plate 9 is used and two plates are joined, as shown in the right diagram of FIG. 7B (the left diagram shows the edge of a conventional two-layer plate fin), reducing air flow resistance and improving performance. In the above embodiment, the cut-out 16 of the heat transfer flow path forming portion 14 of the first plate 9 is only on both longitudinal edge portions of the heat transfer flow path forming portion 14, but this may be configured so that the flat portion between the portions of the heat transfer flow path forming portion 14 corresponding to the heat transfer flow paths 8 are also cut out 16 as shown in FIG. 8. The cut 16 may be performed while leaving protruding pieces 18 for forming fin stacking spacing forming convex portions 17 (not shown) on both sides of the portion of the heat transfer flow path forming portion 14 corresponding to the heat transfer flow path 8, protruding in a direction intersecting the heat transfer flow path 8, so that the entire portion has an approximately fishbone shape.

[0026] This allows more flat plate-like portions to be removed, making it possible to reduce weight more effectively.

[0027] In the present embodiment, the header flow paths A11, B12 of the plate fin 2a are provided separately on the end plate portions 15a, 15b at both ends in the longitudinal direction, but as shown in Fig. 9, the header flow paths A11, B12 may be provided together on one end plate portion 15a. In the example of Fig. 9, the protruding pieces 18 for forming the fin stacking interval forming convex portions 17 (not shown) on both sides of the heat transfer flow path forming portion 14 corresponding to the heat transfer flow path 8 are cut off 16 while remaining in a shape that protrudes in a direction intersecting the heat transfer flow path 8, so that the overall configuration is substantially fishbone-shaped. However, as shown in Figs. 2 and 3, at least the flat plate portions on both longitudinal edges of the heat transfer flow path forming portion 14 may be cut off 16 as in the first embodiment. By providing the header flow paths A11, B12 together on one end plate portion 15a in this manner, the connection to the piping on the refrigeration system side can be performed at one place, improving the workability.

[0028] In addition, the groove shape forming the heat transfer flow path 8 is illustrated as being provided on both the first plate 9 side and the heat transfer flow path forming portion 14 side of the second plate 10, but it may be provided on only one of the first plate 9 side or the heat transfer flow path forming portion 14 of the second plate 10. In addition, the fin stacking spacing forming protrusion 17 may be provided on the flat portion side of the second plate 10.

[0029] [1-3. Effects, etc.] As described above, the plate fin stacked type heat exchanger of the present disclosure is a heat exchanger constructed by stacking a plurality of plate fins 2a, each of which has a pair of header flow paths A11, B12 and a heat transfer flow path 8 connecting the header flow paths A11, B12. The plate fins 2a are constructed by joining two plates, and one of the two plates, the first plate 9, is in a flat state maintaining a rectangular shape, while the other, the second plate 10, is equipped with a heat transfer flow path forming portion 14 that forms a heat transfer flow path between itself and the first plate 9, and flat end plate portions 15a, 15b provided on both longitudinal ends of the heat transfer flow path forming portion 14, and at least both plate edge portions 16 of the heat transfer flow path forming portion 14 are cut away.

[0030] This significantly reduces the flat portion of the second plate 10, one of the plates that constitutes the plate fins 2a, and therefore the weight of the entire heat exchanger can be significantly reduced. Moreover, the plate thickness of the edge of the plate fins 2a is thin, being the same as the plate thickness of the first plate 9, so that the growth of water droplets that condense and adhere to the edge of the plate fins on the side where the second fluid flows in can be suppressed, and the water splash phenomenon in which large water droplets are blown away by a downstream blower fan or the like can be suppressed, improving reliability.

[0031] Furthermore, in the plate fin stacked type heat exchanger of the present disclosure, the second plate 10 can also have a fishbone-shaped configuration in which the heat transfer flow path forming portion 14 is cut away on both sides of the heat transfer flow path portion, leaving protruding pieces 18 that protrude in a direction intersecting with the heat transfer flow path corresponding portion.

[0032] This makes it possible to more effectively reduce the flat portion of the second plate 10, thereby enabling the weight of the entire heat exchanger to be further reduced significantly.

[0033] (Embodiment 2) The second embodiment will be described below with reference to FIGS.

[0034] [2-1. Configuration] FIG. 9 is a diagram of a refrigeration cycle of an air conditioner configured using the plate fin stack type heat exchanger in accordance with the first embodiment, and FIG. 10 is a schematic cross-sectional view showing an indoor unit of the same air conditioner.

[0035] 9 and 10, this air conditioner is composed of an outdoor unit 51 and an indoor unit 52 connected to the outdoor unit 51. The outdoor unit 51 is provided with a compressor 53 for compressing the refrigerant, a four-way valve 54 for switching the refrigerant circuit during cooling and heating operation, an outdoor heat exchanger 55 for exchanging heat between the refrigerant and the outside air, a pressure reducer 56 for reducing the pressure of the refrigerant, and an outdoor blower 59. The indoor unit 52 is provided with an indoor heat exchanger 57 for exchanging heat between the refrigerant and the indoor air, and an indoor blower 58. The plate-fin laminated type heat exchanger exemplified in the first embodiment is used for the indoor heat exchanger 57, and the compressor 53, the four-way valve 54, the indoor heat exchanger 57, the pressure reducer 56, and the outdoor heat exchanger 55 are connected by a refrigerant circuit to form a heat pump type refrigeration cycle.

[0036] [2-2. Operation] In the air conditioner having the above configuration, during cooling operation, the four-way valve 54 is switched so that the discharge side of the compressor 53 communicates with the outdoor heat exchanger 55. As a result, the refrigerant compressed by the compressor 53 becomes a high-temperature, high-pressure gas-phase refrigerant and is sent to the outdoor heat exchanger 55 through the four-way valve 54. Then, the refrigerant exchanges heat with the outdoor air, dissipates heat, becomes a high-pressure liquid-phase refrigerant, and is sent to the pressure reducer 56. The pressure is reduced in the pressure reducer 56 to become a low-temperature, low-pressure two-phase refrigerant, and is sent to the indoor unit 52. In the indoor unit 52, the refrigerant enters the indoor heat exchanger 57, exchanges heat with the indoor air, absorbs heat, and evaporates to become a low-temperature gas refrigerant. At this time, the indoor air is cooled to cool the room. The refrigerant then returns to the outdoor unit 51 and is returned to the compressor 53 via the four-way valve 54.

[0037] Here, condensation water formed by cooling indoor air adheres to the plate fin edge of the indoor heat exchanger 57, but since the plate thickness of the plate fin edge is thin, the water does not grow into large droplets, but runs along the fin surface and is collected in the water receiving gutter and discharged to the outside. Therefore, the indoor blower 58 is prevented from being damaged by water splashing, and the reliability of the air conditioner is improved.

[0038] On the other hand, during heating operation, the four-way valve 54 is switched so that the discharge side of the compressor 53 communicates with the indoor unit 52. As a result, the refrigerant compressed by the compressor 53 becomes a high-temperature, high-pressure refrigerant and passes through the four-way valve 54 to be sent to the indoor unit 52. The high-temperature, high-pressure refrigerant enters the indoor heat exchanger 57, exchanges heat with the indoor air, releases heat, and is cooled to become a high-pressure liquid refrigerant. At this time, the indoor air is heated to heat the room. The refrigerant is then sent to the pressure reducer 56, where it is reduced in pressure to become a low-temperature, low-pressure two-phase refrigerant, which is then sent to the outdoor heat exchanger 55, where it exchanges heat with the outdoor air and evaporates, and is returned to the compressor 53 via the four-way valve 54.

[0039] [2-3. Effects, etc.] The refrigeration system of the present disclosure uses a heat exchanger configured using the plate fins 2a shown in the first embodiment for the indoor heat exchanger 57, thereby making it possible to provide a highly reliable refrigeration system that reduces damage caused by water splashing from the heat exchanger.

[0040] [Other embodiments] The plate-fin stacked heat exchanger and the refrigeration system using the same according to the present invention have been described above using the above-mentioned embodiment, but the present invention is not limited thereto, and various modifications, substitutions, additions, omissions, etc. can be made. For example, the first fluid is a refrigerant and the second fluid is air, but the present invention is not limited thereto. In addition, an air conditioner is exemplified as the refrigeration system, but it may be a refrigerator or a freezer case, or it may be a heat pump water heater in which the second fluid is water. In other words, the embodiment disclosed here is illustrative in all respects and not restrictive, and the scope of the present invention is indicated by the claims, and includes all modifications within the meaning and scope equivalent to the claims. [Industrial Applicability]

[0041] As described above, the present invention provides a plate-fin stacked type heat exchanger that is lightweight and has high reliability by suppressing the water splash phenomenon, and a highly reliable refrigeration system using the same. Therefore, the present invention can be widely used in heat exchangers for home and commercial air conditioners and various refrigeration equipment, and has great industrial value. [Explanation of symbols]

[0042] 1 heat exchanger 2 Plate Fin Stack 2a Plate fin 3a, 3b End plates 4 Pipe A 5 Tube B 7 Fastening means (bolts and nuts) 8 Heat transfer path 9 First Plate 10 Second Plate 11 Header passage A 12 Header passage B 14 Heat transfer channel forming part 15a,15b End plate part 16 Excision 17 Fin stacking interval forming protrusion 18 Projecting piece 51 Outdoor unit 52 Indoor unit 53 Compressor 54 Four-way valve 55 Outdoor heat exchanger 56 Pressure reducer 57 Indoor heat exchanger 58 Indoor fan 59 Outdoor blower

Claims

1. A plate-fin stacked heat exchanger comprising a plurality of stacked plate fins, each having a pair of header flow paths and a heat transfer flow path connecting the header flow paths, the plate fins being formed by joining two plates, one of the two plates, a first plate, being in a flat state maintaining a rectangular shape, and the other, a second plate, having a heat transfer flow path forming portion that forms a heat transfer flow path between the first plate and the other, a second plate, having flat end plate portions provided on both longitudinal ends of the heat transfer flow path forming portion, and at least both plate edge portions of the heat transfer flow path forming portion are removed.

2. 2. The plate-fin stacked type heat exchanger according to claim 1, wherein the second plate is cut away from the heat transfer flow path forming portion at a portion corresponding to the heat transfer flow path, leaving protruding pieces protruding in a direction intersecting the heat transfer flow path on both sides of the heat transfer flow path forming portion.

3. 3. The plate-fin stacked type heat exchanger according to claim 1, wherein the pair of header flow paths are provided separately in each of the end plate portions at both ends of the heat transfer flow path forming portion, or are provided collectively in either one of the end plate portions.

4. A refrigeration system in which the heat exchanger is the plate fin stacked type heat exchanger according to any one of claims 1 to 3.

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