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US20130299152A1 - Heat exchanger and air conditioner - Google Patents

Heat exchanger and air conditioner Download PDF

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Publication number
US20130299152A1
US20130299152A1 US13/980,584 US201213980584A US2013299152A1 US 20130299152 A1 US20130299152 A1 US 20130299152A1 US 201213980584 A US201213980584 A US 201213980584A US 2013299152 A1 US2013299152 A1 US 2013299152A1
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US
United States
Prior art keywords
upwind
heat exchanger
heat
air
plates
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US13/980,584
Inventor
Yasutaka Ohtani
Yoshio Oritani
Takuya Kazusa
Masanori Jindou
Junichi Hamadate
Shun Yoshioka
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Daikin Industries Ltd
Original Assignee
Daikin Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Daikin Industries Ltd filed Critical Daikin Industries Ltd
Assigned to DAIKIN INDUSTRIES, LTD. reassignment DAIKIN INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: YOSHIOKA, SHUN, HAMADATE, Junichi, KAZUSA, Takuya, ORITANI, YOSHIO, JINDOU, MASANORI, OHTANI, Yasutaka
Publication of US20130299152A1 publication Critical patent/US20130299152A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B39/00—Evaporators; Condensers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00—Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/04—Preventing the formation of frost or condensate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/053—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
    • F28D1/0535—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight the conduits having a non-circular cross-section
    • F28D1/05366—Assemblies of conduits connected to common headers, e.g. core type radiators
    • F28D1/05383—Assemblies of conduits connected to common headers, e.g. core type radiators with multiple rows of conduits or with multi-channel conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/02—Tubular elements of cross-section which is non-circular
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
    • F28F1/32—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means having portions engaging further tubular elements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
    • F28F1/32—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means having portions engaging further tubular elements
    • F28F1/325—Fins with openings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0068—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for refrigerant cycles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2215/00—Fins
    • F28F2215/04—Assemblies of fins having different features, e.g. with different fin densities
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2215/00—Fins
    • F28F2215/12—Fins with U-shaped slots for laterally inserting conduits

Definitions

  • the present invention relates to heat exchangers having a flat tube and a fin and configured to exchange heat between a fluid flowing in the flat tube and air, and air conditioners having the heat exchangers.
  • Patent Document 1 and Patent Document 2 show heat exchangers of this type.
  • a plurality of flat tubes each extending in a horizontal direction, are arranged one above another with a predetermined space between the flat tubes, and plate-like fins are arranged in a direction along which the flat tubes extend, with a predetermined space between the fins.
  • FIG. 2 of Patent Document 2 elongated cutouts are formed in the fins, and the flat tube is inserted in each of the cutouts.
  • air flowing in an air passage between adjacent flat tubes is heat exchanged with a fluid flowing in the flat tube.
  • the present invention is thus intended to prevent frost, in a heat exchanger having a plurality of flat tubes and a plurality of fins, from adhering to a surface of each fin in an air passage.
  • the first aspect of the present invention is directed to a heat exchanger, including: a plurality of flat tubes ( 33 ) arranged one above another such that flat surfaces thereof face each other; and a plurality of vertically extending, plate-like fins ( 36 ) arranged in an extension direction of the flat tubes ( 33 ), wherein each of the fins ( 36 ) includes a plurality of intermediate plates ( 70 ) arranged one above another and dividing a space between adjacent ones of the flat tubes ( 33 ) into air passages ( 40 ), a plurality of tube insertion portions ( 46 ) each provided between vertically adjacent ones of the intermediate plates ( 70 ), with an upwind side thereof being open such that a corresponding one of the flat tubes ( 33 ) is inserted therein, a vertically extending downwind plate ( 75 ) that is continuous with downwind ends of the plurality of intermediate plates ( 70 ) arranged one above another, and a plurality of upwind plates ( 77 ) extending further toward an upwind side than the flat tubes ( 33 )
  • a plurality of upwind plates ( 77 ) project from the upwind ends of the plurality of intermediate plates ( 70 ) to the upwind side.
  • the air passes through the heat exchanger serving as an evaporator, the air is cooled first by the upwind plates ( 77 ).
  • the air is cooled by the upwind plates ( 77 ) to a temperature equal to or lower than a dew point, moisture in the air is condensed.
  • the temperature of the air flowing on the lateral sides of the upwind plates ( 77 ) is equal to or lower than 0° C., moisture in the air turns into frost on the surface of the upwind plates ( 77 ).
  • the air is dehumidified.
  • the air dehumidified in this manner flows in the air passages ( 40 ) along the intermediate plates ( 70 ).
  • the intermediate plates ( 70 ) are located relatively close to the flat tubes ( 33 ), and thus, the air flowing in the air passages ( 40 ) is cooled rapidly.
  • this air has been dehumidified by the upwind plates ( 77 ), and therefore, the accumulation of frost on the surfaces of the intermediate plate ( 70 ) is reduced.
  • each of the upwind plates ( 77 ) is provided with an upwind side heat-transfer portion ( 81 , 91 , 92 , 95 ), and therefore, heat transfer between the air and the upwind plates ( 77 ) is promoted.
  • the air flowing on the lateral sides of the upwind plates ( 77 ) can be easily cooled, and the effect of dehumidifying the air is improved.
  • the accumulation of frost on the surfaces of the intermediate plates ( 70 ) can be further advantageously reduced.
  • the second aspect of the present invention is that in the first aspect of the present invention, the upwind side heat-transfer portion includes a rib ( 91 , 92 ) which extends in a protruding direction of the upwind plates ( 77 ).
  • the upwind plate ( 77 ) is provided with the rib ( 91 , 92 ).
  • the rib ( 91 , 92 ) comprises an upwind side heat-transfer portion.
  • the upwind plate ( 77 ) projects from the intermediate plate ( 70 ). This may lead to easy bending of the upwind plate ( 77 ) in a horizontal direction with respect to the intermediate plate ( 70 ).
  • the rib ( 91 , 92 ) of the upwind plate ( 77 ) is provided so as to extend in the projecting direction of the upwind plate ( 77 ) to increase the bending strength of the upwind plate ( 77 ) in the horizontal direction.
  • the upwind side heat-transfer portion includes an intermediate heat-transfer portion ( 81 , 95 ) provided at a middle portion, in a vertical direction, of each of the upwind plates ( 77 ), and the rib ( 91 , 92 ) provided on at least one of an upper side or a low side of the intermediate heat-transfer portion ( 81 , 95 ).
  • the upwind plate ( 77 ) is provided with the intermediate heat-transfer portion ( 81 , 95 ).
  • the intermediate heat-transfer portion ( 81 , 95 ) comprises an upwind side heat-transfer portion. Since the intermediate heat-transfer portion ( 81 , 95 ) is provided at a middle portion, in the vertical direction, of the upwind plate ( 77 ), heat transfer between the air and the intermediate heat-transfer portion ( 81 , 95 ) is promoted, and the effect of cooling the air is improved.
  • the intermediate heat-transfer portion ( 81 , 95 ) provided on the upwind plate ( 77 ) may easily lead the air to the upper side or the lower side of the intermediate heat-transfer portion ( 81 , 95 ).
  • the rib ( 91 , 92 ) is provided on the upper side or the lower side of the intermediate heat-transfer portion ( 81 , 95 ), and therefore, heat transfer between the air and the rib ( 91 , 92 ) is promoted as well. As a result, the effect of cooling the air flowing on the lateral sides of the upwind plates ( 77 ) is further improved.
  • the upwind side heat-transfer portion includes a protrusion ( 81 ) which extends in a direction orthogonal to an air passage direction.
  • the upwind plate ( 77 ) is provided with the protrusion ( 81 ).
  • the protrusion ( 81 ) comprises an upwind side heat-transfer portion. Since the protrusion ( 81 ) extends in a direction which intersects with the air passage direction, heat transfer between the air and the protrusion ( 81 ) is promoted, and the effect of cooling the air is improved.
  • the fifth aspect of the present invention is that in any one of the first to fourth aspects of the present invention, the upwind side heat-transfer portion includes a raised portion ( 95 ) formed by cutting and bending part of the fin ( 36 ).
  • the upwind plate ( 77 ) is provided with the raised portion ( 95 ) as an upwind side heat-transfer portion. As a result, heat transfer between the air and the raised portion ( 95 ) is promoted, and the effect of cooling the air is improved.
  • the sixth aspect of the present invention is directed to an air conditioner, and having a refrigerant circuit ( 20 ) including the heat exchanger ( 30 ) of any one of the first to fifth aspects of the present invention, wherein the refrigerant circuit ( 20 ) performs a refrigeration cycle by circulating a refrigerant.
  • the heat exchanger ( 30 ) of the first to fifth aspects of the present invention is applied to the air conditioner.
  • the heat exchanger ( 30 ) serving as an evaporator the accumulation of frost on the surfaces of the intermediate plates ( 70 ) which partition the air passages ( 40 ) is reduced.
  • the upwind plates ( 77 ) are provided so as to extend from the intermediate plates ( 70 ) of the fin ( 36 ) to the upwind side, and each of the upwind plates ( 77 ) is provided with the upwind side heat-transfer portion ( 81 , 91 , 92 , 95 ).
  • the air before flowing into the air passages ( 40 ) can be dehumidified by the upwind plates ( 77 ). This can reduce the accumulation of frost on the surfaces of the intermediate plates ( 70 ), and thus, it is possible to prevent a reduction in heat-transfer rate of the fin ( 36 ), and an increase in flow pass resistance of the air passages ( 40 ).
  • the rib ( 91 , 92 ) can improve the effect of cooling the air, and prevent bending of the upwind plates ( 77 ). Since leaning of the upwind plates ( 77 ) is prevented as mentioned, the air can flow evenly into the air passages ( 40 ). As a result, reliability of the heat exchanger can be ensured.
  • heat transfer between the air and the upwind plates ( 77 ) can be promoted, and the effect of cooling the air by the upwind plates ( 77 ) can be further improved.
  • the tip of the raised portion ( 95 ) is in contact with the adjacent upwind plate ( 77 ), thereby preventing the upwind plate ( 77 ) from leaning horizontally.
  • the amount of frost adhering to the intermediate plates ( 70 ) facing the air passages ( 40 ) can be reduced.
  • FIG. 1 is a refrigerant circuit diagram showing a schematic configuration of an air conditioner having a heat exchanger of an embodiment.
  • FIG. 2 is an oblique view schematically showing the heat exchanger of the embodiment.
  • FIG. 3 is a partial cross-sectional view of the front side of the heat exchanger of the embodiment.
  • FIG. 4 is a cross-sectional view of part of the heat exchanger taken along the line A-A of FIG. 3 .
  • FIG. 5 shows a main part of a fin of the heat exchanger of the embodiment.
  • FIG. 5(A) is a front side of the fin.
  • FIG. 5(B) is a cross-sectional view taken along the line B-B of FIG. 5(A) .
  • FIG. 6 shows cross-sectional views of the fins of the heat exchanger of the embodiment.
  • FIG. 6(A) is a cross-section taken along the line C-C of FIG. 5 .
  • FIG. 6(B) is a cross-section taken along the line D-D of FIG. 5 .
  • a heat exchanger ( 30 ) of the embodiment comprises an outdoor heat exchanger ( 23 ) of an air conditioner ( 10 ) described later.
  • the air conditioner ( 10 ) having the heat exchanger ( 30 ) of the present embodiment will be described with reference to FIG. 1 .
  • the air conditioner ( 10 ) has an outdoor unit ( 11 ) and an indoor unit ( 12 ).
  • the outdoor unit ( 11 ) and the indoor unit ( 12 ) are connected to each other via a liquid communication pipe ( 13 ) and a gas communication pipe ( 14 ).
  • a refrigerant circuit ( 20 ) is formed by the outdoor unit ( 11 ), the indoor unit ( 12 ), the liquid communication pipe ( 13 ), and the gas communication pipe ( 14 ).
  • the refrigerant circuit ( 20 ) includes a compressor ( 21 ), a four-way valve ( 22 ), an outdoor heat exchanger ( 23 ), an expansion valve ( 24 ), and an indoor heat exchanger ( 25 ).
  • the compressor ( 21 ), the four-way valve ( 22 ), the outdoor heat exchanger ( 23 ), and the expansion valve ( 24 ) are accommodated in the outdoor unit ( 11 ).
  • the outdoor unit ( 11 ) is provided with an outdoor fan ( 15 ) configured to supply outdoor air to the outdoor heat exchanger ( 23 ).
  • the indoor heat exchanger ( 25 ) is accommodated in the indoor unit ( 12 ).
  • the indoor unit ( 12 ) is provided with an indoor fan ( 16 ) configured to supply indoor air to the indoor heat exchanger ( 25 ).
  • the refrigerant circuit ( 20 ) is a closed circuit filled with a refrigerant.
  • a discharge side of the compressor ( 21 ) is connected to a first port of the four-way valve ( 22 ), and a suction side of the compressor ( 21 ) is connected to a second port of the four-way valve ( 22 ).
  • the outdoor heat exchanger ( 23 ), the expansion valve ( 24 ), and the indoor heat exchanger ( 25 ) are provided sequentially from a third port to a fourth port of the four-way valve ( 22 ).
  • the compressor ( 21 ) is a scroll type or rotary type hermetic compressor.
  • the four-way valve ( 22 ) switches between a first state (the state shown in broken line in FIG. 1 ) in which the first port communicates with the third port, and the second port communicates with the fourth port, and a second state (the state shown in solid line in FIG. 1 ) in which the first port communicates with the fourth port, and the second port communicates with the third port.
  • the expansion valve ( 24 ) is a so-called electronic expansion valve ( 24 ).
  • the outdoor heat exchanger ( 23 ) the outdoor air is heat exchanged with the refrigerant.
  • the outdoor heat exchanger ( 23 ) is comprised of the heat exchanger ( 30 ) of the present embodiment.
  • the indoor heat exchanger ( 25 ) the indoor air is heat exchanged with the refrigerant.
  • the indoor heat exchanger ( 25 ) is comprised of a so-called cross-fin type fin-and-tube heat exchanger having a circular heat-transfer tube.
  • the air conditioner ( 10 ) performs a cooling operation.
  • the four-way valve ( 22 ) is set to the first state during the cooling operation.
  • the outdoor fan ( 15 ) and the indoor fan ( 16 ) are driven during the cooling operation.
  • the refrigerant circuit ( 20 ) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor ( 21 ) passes through the four-way valve ( 22 ), flows into the outdoor heat exchanger ( 23 ), and dissipates heat to the outdoor air and condenses. The refrigerant flowing out of the outdoor heat exchanger ( 23 ) expands when it passes through the expansion valve ( 24 ), flows into the indoor heat exchanger ( 25 ), and takes heat from the indoor air and evaporates. The refrigerant flowing out of the indoor heat exchanger ( 25 ) passes through the four-way valve ( 22 ) and is then sucked into the compressor ( 21 ) and compressed. The indoor unit ( 12 ) supplies air which has been cooled in the indoor heat exchanger ( 25 ) to an indoor space.
  • the air conditioner ( 10 ) performs a heating operation.
  • the four-way valve ( 22 ) is set to the second state during the heating operation.
  • the outdoor fan ( 15 ) and the indoor fan ( 16 ) are driven during the heating operation.
  • the refrigerant circuit ( 20 ) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor ( 21 ) passes the four-way valve ( 22 ), flows into the indoor heat exchanger ( 25 ), and dissipates heat to the indoor air and condenses. The refrigerant flowing out of the indoor heat exchanger ( 25 ) expands when it passes through the expansion valve ( 24 ), flows into the outdoor heat exchanger ( 23 ), and takes heat from the outdoor air and evaporates. The refrigerant flowing out of the outdoor heat exchanger ( 23 ) passes through the four-way valve ( 22 ) and is then sucked into the compressor ( 21 ) and compressed. The indoor unit ( 12 ) supplies air which has been heated in the indoor heat exchanger ( 25 ) to an indoor space.
  • the outdoor heat exchanger ( 23 ) functions as an evaporator in the heating operation.
  • the evaporation temperature of the refrigerant in the outdoor heat exchanger ( 23 ) may sometimes be below 0° C.
  • the moisture in the outdoor air turns into frost and adheres to the outdoor heat exchanger ( 23 ).
  • the air conditioner ( 10 ) performs a defrosting operation every time a duration of the heating operation reaches a predetermined value (e.g., several tens of minutes), for example.
  • the four-way valve ( 22 ) is switched from the second state to the first state, and the outdoor fan ( 15 ) and the indoor fan ( 16 ) are stopped.
  • a high temperature refrigerant discharged from the compressor ( 21 ) is supplied to the outdoor heat exchanger ( 23 ).
  • the frost adhering to the surface of the outdoor heat exchanger ( 23 ) is heated and melted by the refrigerant.
  • the refrigerant which dissipates heat in the outdoor heat exchanger ( 23 ) sequentially passes through the expansion valve ( 24 ) and the indoor heat exchanger ( 25 ), and is then sucked into the compressor ( 21 ) and compressed.
  • the heating operation starts again. That is, the four-way valve ( 22 ) is switched from the first state to the second state, and the outdoor fan ( 15 ) and the indoor fan ( 16 ) are driven again.
  • the heat exchanger ( 30 ) of the present embodiment which comprises the outdoor heat exchanger ( 23 ) of the air conditioner ( 10 ) will be described with reference to FIGS. 2 to 6 .
  • the heat exchanger ( 30 ) of the present embodiment includes one first header collecting pipe ( 31 ), one second header collecting pipe ( 32 ), a plurality of flat tubes ( 33 ), and a plurality of fins ( 35 ).
  • the first header collecting pipe ( 31 ), the second header collecting pipe ( 32 ), the flat tubes ( 33 ), and the fins ( 35 ) are all aluminum alloy members, and are attached to one another with solder.
  • Both of the first header collecting pipe ( 31 ) and the second header collecting pipe ( 32 ) are in an elongated hollow cylindrical shape, with both ends closed.
  • the first header collecting pipe ( 31 ) is provided upright at the left end of the heat exchanger ( 30 )
  • the second header collecting pipe ( 32 ) is provided upright at the right end of the heat exchanger ( 30 ).
  • the first header collecting pipe ( 31 ) and the second header collecting pipe ( 32 ) are provided such that their axial directions are vertical.
  • the flat tube ( 33 ) is a heat-transfer tube having a flat oblong cross section or a rectangular cross section with rounded corners.
  • the plurality of flat tubes ( 33 ) extend in a horizontal direction, and are arranged such that the flat surfaces thereof face each other. Further, the plurality of flat tubes ( 33 ) are arranged one above another with a predetermined space between the flat tubes ( 33 ).
  • One end of each of the flat tubes ( 33 ) is inserted in the first header collecting pipe ( 31 ), and the other end of the flat tube ( 33 ) is inserted in the second header collecting pipe ( 32 ).
  • Each fin ( 36 ) is in a plate-like shape, and the fins ( 36 ) are arranged in an extension direction of the flat tube ( 33 ) with a predetermined space between the fins ( 36 ). In other words, the fins ( 36 ) are arranged to be substantially orthogonal to the extension direction of the flat tube ( 33 ). As will be described in detail later, an area of each fin ( 36 ) which is located between vertically adjacent flat tubes ( 33 ) comprises an intermediate plate ( 70 ).
  • a space between vertically adjacent flat tubes ( 33 ) is divided into a plurality of air passages ( 40 ) by the intermediate plates ( 70 ) of the fins ( 36 ).
  • the refrigerant flowing in the fluid passages ( 34 ) of the flat tube ( 33 ) exchanges heat with the air flowing in the air passages ( 40 ).
  • each of the fins ( 36 ) is a vertically elongate plate-like fin formed by pressing a metal plate.
  • the thickness of each fin ( 36 ) is approximately 0.1 mm.
  • the fin ( 36 ) is provided with a plurality of elongate cutouts ( 45 ) each extending in a width direction (i.e., in an air passage direction) of the fin ( 36 ) from a leading edge ( 38 ) of the fin ( 36 ).
  • the plurality of cutouts ( 45 ) are formed in the fin ( 36 ) at predetermined intervals in a longitudinal direction (i.e., a vertical direction) of the fin ( 36 ).
  • a portion between the intermediate plates ( 70 ) of the fins ( 36 ) comprises a tube insertion portion ( 46 ).
  • the flat tube ( 33 ) is inserted in the tube insertion portion ( 46 ) from the open upwind side, and is held.
  • the width of the tube insertion portion ( 46 ) in the vertical direction is substantially equal to the width of the thickness of the flat tube ( 33 ), and the length of the tube insertion portion ( 46 ) is substantially equal to the width of the flat tube ( 33 ).
  • the flat tube ( 33 ) is inserted in the tube insertion portion ( 46 ) of the fin ( 36 ) from the leading edge ( 38 ) of the fin ( 36 ).
  • the flat tube ( 33 ) is attached to the periphery of the tube insertion portion ( 46 ) with solder. That is, the flat tube ( 33 ) is fitted to the periphery of the tube insertion portion ( 46 ) which is part of the cutout ( 45 ).
  • the fin ( 36 ) includes a plurality of intermediate plates ( 70 ) in areas between vertically adjacent flat tubes ( 33 ), a downwind plate ( 75 ) provided on the downwind side of the intermediate plates ( 70 ), and an upwind plate ( 77 ) provided on the upwind side of each of the plurality of intermediate plates ( 70 ).
  • the intermediate plates ( 70 ) divide the space between vertically adjacent flat tubes ( 33 ) into the air passages ( 40 ). That is, the intermediate plates ( 70 ) face the air passages ( 40 ).
  • the downwind plate ( 75 ) is continuous with the downwind ends of all the intermediate plates ( 70 ) arranged one above another.
  • Each of the upwind plate ( 77 ) projects from a middle portion in the vertical direction of the upwind end of each intermediate plate ( 70 ) toward the upwind side.
  • the height of each upwind plate ( 77 ) is smaller than the height of each intermediate plate ( 70 ), and the width of the upwind plate ( 77 ) is narrower than the width of the intermediate plate ( 70 ).
  • the fin ( 36 ) is provided with louvers ( 50 a , 50 b ) and protrusions ( 81 - 83 ).
  • the protrusions ( 81 - 83 ) are located upwind of the louvers ( 50 a , 50 b ).
  • the numbers of the protrusions ( 81 - 83 ) and the louvers ( 50 a , 50 b ) described below are merely examples.
  • the fin ( 36 ) is provided with three protrusions ( 81 - 83 ) in an upwind side area.
  • the three protrusions ( 81 - 83 ) are arranged side by side in the air passage direction (i.e., the direction from the leading edge ( 38 ) to the trailing edge ( 39 ) of the fin ( 36 )). That is, the fin ( 36 ) is provided with a first protrusion ( 81 ), a second protrusion ( 82 ), and a third protrusion ( 83 ) sequentially from the upwind side to the downwind side.
  • the first protrusion ( 81 ) lies across the upwind plate ( 77 ) and the intermediate plate ( 70 ), and the second protrusion ( 82 ) and the third protrusion ( 83 ) are provided on the intermediate plate ( 70 ).
  • Each of the protrusions ( 81 - 83 ) has an inverted V shape formed by making the fin ( 36 ) protrude toward the air passage ( 40 ).
  • the three protrusions ( 81 - 83 ) protrude to the same direction.
  • the protrusions ( 81 - 83 ) protrude to the right when viewed from the leading edge ( 38 ) of the fin ( 36 ).
  • Ridges ( 81 a , 82 a , 83 a ) of the protrusions ( 81 - 83 ) are substantially in parallel with the leading edge ( 38 ) of the fin ( 36 ). That is, the ridges ( 81 a , 82 a , 83 a ) of the protrusions ( 81 - 83 ) intersect with the airflow direction in the air passage ( 40 ).
  • the width W 1 of the first protrusion ( 81 ) in the air passage direction is smaller than the width W 2 of the second protrusion ( 82 ) in the air passage direction
  • the width W 3 of the third protrusion ( 83 ) is smaller than the width W 1 of the first protrusion ( 81 ) in the air passage direction (W 1 ⁇ W 2 ⁇ W 3 ).
  • the intermediate plate ( 70 ) of the fin ( 36 ) is provided with a group of louvers ( 50 a , 50 b ) at the downwind side of the protrusions ( 81 - 83 ).
  • the louvers ( 50 a , 50 b ) are obtained by giving a plurality of slit-like cuts in the intermediate plate ( 70 ) and plastically deforming a portion between adjacent cuts as if twisting the portion.
  • the longitudinal direction of each louver ( 50 a , 50 b ) is substantially parallel to the leading edge ( 38 ) of the fin ( 36 ) (i.e., the vertical direction). That is, the longitudinal direction of each louver ( 50 a , 50 b ) intersects with the air passage direction.
  • the lengths of the louvers ( 50 a , 50 b ) are equal to each other.
  • the louvers ( 50 a , 50 b ) are tilted with respect to their peripheral flat portions. Specifically, bent-out ends ( 53 a , 53 b ) on the upwind side of the louvers ( 50 a , 50 b ) protrude to the left when viewed from the leading edge ( 38 ) of the fin ( 36 ). On the other hand, bent-out ends ( 53 a , 53 b ) of the louvers ( 50 a , 50 b ) on the downwind side protrude to the right when viewed from the leading edge ( 38 ) of the fin ( 36 ).
  • each of the bent-out ends ( 53 a , 53 b ) of the louvers ( 50 a , 50 b ) includes a main edge ( 54 a , 54 b ), an upper edge ( 55 a , 55 b ), a lower edge ( 56 a , 56 b ).
  • the main edge ( 54 a , 54 b ) extends substantially in parallel with the leading edge ( 38 ) of the fin ( 36 ).
  • the upper edge ( 55 a , 55 b ) extends from the upper end of the main edge ( 54 a , 54 b ) to the upper end of the louver ( 50 a , 50 b ), and is tilted with respect to the main edge ( 54 a , 54 b ).
  • the lower edge ( 56 a , 56 b ) extends from the lower end of the main edge ( 54 a , 54 b ) to the lower end of the louver ( 50 a , 50 b ), and is tilted relative to the main edge ( 54 a , 54 b ).
  • a tilt angle ⁇ 2 of the lower edge ( 56 a ) with respect to the main edge ( 54 a ) is smaller than a tilt angle ⁇ 1 of the upper edge ( 55 a ) with respect to the main edge ( 54 a ) (i.e., ⁇ 2 ⁇ 1 ).
  • the lower edge ( 56 a ) is longer than the upper edge ( 55 a ).
  • the upwind side louver ( 50 a ) is an asymmetric louver in which the shape of the bent-out end ( 53 a ) is asymmetric in the vertical direction.
  • the louver ( 50 b ) is a symmetric louver in which the shape of the bent-out end ( 53 b ) is symmetric in the vertical direction.
  • one auxiliary protrusion ( 85 ) lies across the intermediate plate ( 70 ) and the downwind plate ( 75 ).
  • the auxiliary protrusion ( 85 ) has an inverted V shape formed by making the fin ( 36 ) protrude.
  • each auxiliary protrusion ( 85 ) protrudes to the right when viewed from the leading edge ( 38 ) of the fin ( 36 ).
  • the ridge ( 85 a ) of the auxiliary protrusion ( 85 ) is substantially in parallel with the leading edge ( 38 ) of the fin ( 36 ). That is, the ridge ( 85 a ) of the auxiliary protrusion ( 85 ) intersects with the airflow direction in the air passage ( 40 ).
  • the lower end of the auxiliary protrusion ( 85 ) is tilted downward toward the downwind side.
  • the width W 5 of the auxiliary protrusion ( 85 ) in the air passage direction is smaller than the width W 3 of the third protrusion ( 83 ) in the air passage direction (W 5 ⁇ W 3 ).
  • the downwind plate ( 75 ) of the fin ( 36 ) is provided with a vertically extending water-conducting rib ( 49 ), a plurality of downwind tabs ( 48 ) arranged in the vertical direction, and a plurality of downwind protrusions ( 84 ) each provided between vertically adjacent downwind tabs ( 48 ).
  • the water-conducting rib ( 49 ) is an elongated recessed groove extending vertically along the trailing edge ( 39 ) of the fin ( 36 ).
  • the water-conducting rib ( 49 ) extends from the upper end to the lower end of the downwind plate ( 75 ) of the fin ( 36 ).
  • Each of the downwind tabs ( 48 ) is a small rectangular piece formed by cutting and bending the fin ( 36 ).
  • the downwind tabs ( 48 ) keep a space between the fins ( 36 ), with the tips thereof being in contact with their adjacent fin ( 36 ).
  • Each downwind protrusion ( 84 ) has an inverted V shape formed by making the downwind plate ( 75 ) protrude.
  • each downwind protrusion ( 84 ) protrudes to the right when viewed from the leading edge ( 38 ) of the fin ( 36 ).
  • Ridges ( 84 a ) of the downwind protrusions ( 84 ) are substantially in parallel with the leading edge ( 38 ) of the fin ( 36 ). That is, the ridges ( 84 a ) of the downwind protrusions ( 84 ) intersect with the airflow direction in the air passage ( 40 ).
  • the fin ( 36 ) is provided with two horizontal ribs ( 91 , 92 ), and the above-described first protrusion ( 81 ) which lie across the upwind plate ( 77 ) and the intermediate plate ( 70 ).
  • the first protrusion ( 81 ) comprises an intermediate heat-transfer portion provided at a middle portion, in the vertical direction, of the upwind plate ( 77 ).
  • the first protrusion ( 81 ) comprises an upwind side heat-transfer portion which promotes heat transfer between the fin ( 36 ) and air on the upwind side of the intermediate plate ( 70 ).
  • the upper horizontal rib ( 91 ) is provided at an area on the upper side of the first protrusion ( 81 ) and the upwind tab ( 95 ), and the lower horizontal rib ( 92 ) is provided at an area on the lower side of the first protrusion ( 81 ) and the upwind tab ( 95 ).
  • the horizontal ribs ( 91 , 92 ) are comprised of raised lines which protrude toward the air passage ( 40 ). The direction to which the horizontal ribs ( 91 , 92 ) protrude is the same as the protrusion direction of the protrusions ( 81 , 82 , 83 , 84 ).
  • the upper horizontal rib ( 91 ) extends horizontally from the leading edge ( 38 ) of the fin ( 36 ) to an upper portion of the second protrusion ( 82 ).
  • the lower horizontal rib ( 92 ) extends horizontally from the leading edge ( 38 ) of the fin ( 36 ) to a lower portion of the second protrusion ( 82 ). That is, in the fin ( 36 ), the two horizontal ribs ( 91 , 92 ) extend linearly in the protruding direction of the upwind plates ( 77 ) (i.e., in the air passage direction).
  • the horizontal ribs ( 91 , 92 ) comprise reinforcing ribs which prevent the upwind plate ( 77 ) from being bent toward the air passage ( 40 ) with respect to the intermediate plate ( 70 ) of the fin ( 36 ).
  • the horizontal ribs ( 91 , 92 ) also comprise upwind side heat-transfer portions which promote heat transfer between the fin ( 36 ) and air on the upwind side of the intermediate plate ( 70 ).
  • the upwind tab ( 95 ) as a raised portion is provided on the front side of each of the upwind plates ( 77 ).
  • the upwind tab ( 95 ) comprises an intermediate heat-transfer portion provided at a middle portion, in the vertical direction, of the upwind plate ( 77 ).
  • the upwind tab ( 95 ) is a small rectangular piece formed by cutting and bending the fin ( 36 ) so as to protrude in a thickness direction of the fin ( 36 ).
  • the front surface of the upwind tab ( 95 ) is tilted obliquely downward with respect to the air passage direction (i.e., the horizontal direction).
  • an airflow resistance of the heat exchanger ( 30 ) can be reduced, compared to the case in which the front surface of the upwind tab ( 95 ) is vertical.
  • the upwind tab ( 95 ) keeps a space between the fins ( 36 ), with the tips thereof being in contact with the adjacent fin ( 36 ).
  • the upwind tab ( 95 ) also comprises an upwind side heat-transfer portion which promotes heat transfer between the fin ( 36 ) and air on the upwind side of the intermediate plate ( 70 ).
  • the outdoor heat exchanger ( 23 ) of the present embodiment functions as an evaporator in the heating operation.
  • the evaporation temperature of the refrigerant may sometimes be below 0° C., and frost may adhere to the surface of the fin ( 36 ).
  • the air before flowing into the air passage ( 40 ) is cooled/dehumidified by the upwind plates ( 77 ), thereby reducing the accumulation of frost on the inner side of the air passage ( 40 ).
  • the upwind tab ( 95 ), the first protrusion ( 81 ), and the horizontal ribs ( 91 , 92 ) comprise heat-transfer promotion portions which promote heat transfer between air and the upwind plates ( 77 ).
  • the intermediate plates ( 70 ) are relatively close to the flat tubes ( 33 ), and thus, the air flowing in the air passages ( 40 ) is cooled rapidly. However, this air has been dehumidified before flowing into the air passages ( 40 ), and therefore, the accumulation of frost on the surfaces of the intermediate plates ( 70 ) is reduced.
  • the upwind plates ( 77 ) extend from the intermediate plates ( 70 ) of the fin ( 36 ) toward the upwind side.
  • the air before flowing into the air passages ( 40 ) can be cooled and dehumidified.
  • each of the upwind plates ( 77 ) is provided with the upwind tab ( 95 ), the first protrusion ( 81 ), and the horizontal ribs ( 91 , 92 ), it is possible to promote heat transfer between the air and the upwind plates ( 77 ), and improve the effect of dehumidifying the air.
  • the accumulation of frost on the surfaces of the intermediate plates ( 70 ) is reduced.
  • the two horizontal ribs ( 91 , 92 ) provided on each of the upwind plates ( 77 ) prevent the upwind plates ( 77 ) from being bent in the horizontal direction with respect to the intermediate plate ( 70 ). Such bending of the upwind plates ( 77 ) can be further prevented by the upwind tab ( 95 ) whose tip is brought into contact with the adjacent fin ( 36 ).
  • any of the upwind tab ( 95 ), the first protrusion ( 81 ), and the two horizontal ribs ( 91 , 92 ) may be omitted.
  • each of the upwind plates ( 77 ) may be provided with the louvers ( 50 a , 50 b ) of the above embodiment, and the louvers ( 50 a , 50 b ) may be used as upwind side heat-transfer portions (raised portions).
  • the present invention is useful for a heat exchanger having a flat tube and a fin, and configured to exchange heat between a fluid flowing in the flat tube and air.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
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  • General Engineering & Computer Science (AREA)
  • Geometry (AREA)
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  • Other Air-Conditioning Systems (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

A fin of a heat exchanger includes: a plurality of intermediate plates arranged one above another and dividing a space between adjacent ones of flat tubes into air passages; a plurality of tube insertion portions each provided between vertically adjacent ones of the intermediate plates, with an upwind side thereof being open such that a corresponding one of the flat tubes is inserted therein; a vertically extending downwind plate that is continuous with downwind ends of the plurality of intermediate plates arranged one above another; and a plurality of upwind plates extending further toward an upwind side than the flat tubes from upwind side ends of the intermediate plates. Each of the upwind plates is provided with at least one upwind side heat-transfer portion which projects toward the air passages.

Description

    TECHNICAL FIELD
  • The present invention relates to heat exchangers having a flat tube and a fin and configured to exchange heat between a fluid flowing in the flat tube and air, and air conditioners having the heat exchangers.
    • BACKGROUND ART
  • Heat exchangers having a flat tube and a fin have been known. Patent Document 1 and Patent Document 2 show heat exchangers of this type. In the heat exchangers shown in these patent documents, a plurality of flat tubes, each extending in a horizontal direction, are arranged one above another with a predetermined space between the flat tubes, and plate-like fins are arranged in a direction along which the flat tubes extend, with a predetermined space between the fins. For example, in the heat exchanger shown in FIG. 2 of Patent Document 2, elongated cutouts are formed in the fins, and the flat tube is inserted in each of the cutouts. In this heat exchanger, air flowing in an air passage between adjacent flat tubes is heat exchanged with a fluid flowing in the flat tube.
    • CITATION LIST Patent Document
    • Patent Document 1: Japanese Patent Publication No. 2003-262485
    • Patent Document 2: Japanese Patent Publication No. 2010-054060
    SUMMARY OF THE INVENTION Technical Problem
  • In the heat exchanges shown in Patent Documents 1 and 2, when the air flowing in the air passage is 0° C. or lower, moisture in the air freezes and frost may adhere to the surfaces of the fins. If the amount of frost adhering to the surfaces of the fins increases in the air passage, a heat-transfer rate of the fin may decrease, or a flow pass resistance of the air passage may increase.
  • The present invention is thus intended to prevent frost, in a heat exchanger having a plurality of flat tubes and a plurality of fins, from adhering to a surface of each fin in an air passage.
    • Solution to the Problem
  • The first aspect of the present invention is directed to a heat exchanger, including: a plurality of flat tubes (33) arranged one above another such that flat surfaces thereof face each other; and a plurality of vertically extending, plate-like fins (36) arranged in an extension direction of the flat tubes (33), wherein each of the fins (36) includes a plurality of intermediate plates (70) arranged one above another and dividing a space between adjacent ones of the flat tubes (33) into air passages (40), a plurality of tube insertion portions (46) each provided between vertically adjacent ones of the intermediate plates (70), with an upwind side thereof being open such that a corresponding one of the flat tubes (33) is inserted therein, a vertically extending downwind plate (75) that is continuous with downwind ends of the plurality of intermediate plates (70) arranged one above another, and a plurality of upwind plates (77) extending further toward an upwind side than the flat tubes (33) from upwind side ends of the intermediate plates (70), and each of the upwind plates (77) is provided with at least one upwind side heat-transfer portion (81, 91, 92, 95) which projects in a thickness direction of the fins (36).
  • In the fin (36) of the first aspect of the present invention, a plurality of upwind plates (77) project from the upwind ends of the plurality of intermediate plates (70) to the upwind side. When air passes through the heat exchanger serving as an evaporator, the air is cooled first by the upwind plates (77). When the air is cooled by the upwind plates (77) to a temperature equal to or lower than a dew point, moisture in the air is condensed. When the temperature of the air flowing on the lateral sides of the upwind plates (77) is equal to or lower than 0° C., moisture in the air turns into frost on the surface of the upwind plates (77). In the present invention, since moisture in the air flowing on the lateral sides of the upwind plates (77) is condensed, or turns into frost as described above, the air is dehumidified.
  • The air dehumidified in this manner flows in the air passages (40) along the intermediate plates (70). The intermediate plates (70) are located relatively close to the flat tubes (33), and thus, the air flowing in the air passages (40) is cooled rapidly. However, this air has been dehumidified by the upwind plates (77), and therefore, the accumulation of frost on the surfaces of the intermediate plate (70) is reduced.
  • Here, the air flowing on the lateral sides of the upwind plates (77) is not easily cooled, compared to the air flowing in the air passages (40), because the upwind plates (77) are located relatively far from the flat tubes (33). However, in the fin (36) of the present invention, each of the upwind plates (77) is provided with an upwind side heat-transfer portion (81, 91, 92, 95), and therefore, heat transfer between the air and the upwind plates (77) is promoted. As a result, the air flowing on the lateral sides of the upwind plates (77) can be easily cooled, and the effect of dehumidifying the air is improved. Thus, in the present invention, the accumulation of frost on the surfaces of the intermediate plates (70) can be further advantageously reduced.
  • The second aspect of the present invention is that in the first aspect of the present invention, the upwind side heat-transfer portion includes a rib (91, 92) which extends in a protruding direction of the upwind plates (77).
  • According to the second aspect of the present invention, the upwind plate (77) is provided with the rib (91, 92). The rib (91, 92) comprises an upwind side heat-transfer portion. Thus, the air flowing on the lateral sides of the upwind plates (77) can be easily cooled, and the effect of dehumidifying the air is improved.
  • Further, in the fin (36) of the present invention, the upwind plate (77) projects from the intermediate plate (70). This may lead to easy bending of the upwind plate (77) in a horizontal direction with respect to the intermediate plate (70). However, the rib (91, 92) of the upwind plate (77) is provided so as to extend in the projecting direction of the upwind plate (77) to increase the bending strength of the upwind plate (77) in the horizontal direction. Thus, it is possible to prevent the upwind plate (77) from being bent in the horizontal direction.
  • The third aspect of the present invention is that in the second aspect of the present invention, the upwind side heat-transfer portion includes an intermediate heat-transfer portion (81, 95) provided at a middle portion, in a vertical direction, of each of the upwind plates (77), and the rib (91, 92) provided on at least one of an upper side or a low side of the intermediate heat-transfer portion (81, 95).
  • According to the third aspect of the present invention, the upwind plate (77) is provided with the intermediate heat-transfer portion (81, 95). The intermediate heat-transfer portion (81, 95) comprises an upwind side heat-transfer portion. Since the intermediate heat-transfer portion (81, 95) is provided at a middle portion, in the vertical direction, of the upwind plate (77), heat transfer between the air and the intermediate heat-transfer portion (81, 95) is promoted, and the effect of cooling the air is improved. The intermediate heat-transfer portion (81, 95) provided on the upwind plate (77) may easily lead the air to the upper side or the lower side of the intermediate heat-transfer portion (81, 95). However, in the present invention, the rib (91, 92) is provided on the upper side or the lower side of the intermediate heat-transfer portion (81, 95), and therefore, heat transfer between the air and the rib (91, 92) is promoted as well. As a result, the effect of cooling the air flowing on the lateral sides of the upwind plates (77) is further improved.
  • The fourth aspect of the present invention is that in any one of the first to third aspects of the present invention, the upwind side heat-transfer portion includes a protrusion (81) which extends in a direction orthogonal to an air passage direction.
  • According to the fourth aspect of the present invention, the upwind plate (77) is provided with the protrusion (81). The protrusion (81) comprises an upwind side heat-transfer portion. Since the protrusion (81) extends in a direction which intersects with the air passage direction, heat transfer between the air and the protrusion (81) is promoted, and the effect of cooling the air is improved.
  • The fifth aspect of the present invention is that in any one of the first to fourth aspects of the present invention, the upwind side heat-transfer portion includes a raised portion (95) formed by cutting and bending part of the fin (36).
  • According to the fifth aspect of the present invention, the upwind plate (77) is provided with the raised portion (95) as an upwind side heat-transfer portion. As a result, heat transfer between the air and the raised portion (95) is promoted, and the effect of cooling the air is improved.
  • The sixth aspect of the present invention is directed to an air conditioner, and having a refrigerant circuit (20) including the heat exchanger (30) of any one of the first to fifth aspects of the present invention, wherein the refrigerant circuit (20) performs a refrigeration cycle by circulating a refrigerant.
  • According to the sixth aspect of the present invention, the heat exchanger (30) of the first to fifth aspects of the present invention is applied to the air conditioner. Thus, in the heat exchanger (30) serving as an evaporator, the accumulation of frost on the surfaces of the intermediate plates (70) which partition the air passages (40) is reduced.
    • Advantages of the Invention
  • In the present invention, the upwind plates (77) are provided so as to extend from the intermediate plates (70) of the fin (36) to the upwind side, and each of the upwind plates (77) is provided with the upwind side heat-transfer portion (81, 91, 92, 95). Thus, the air before flowing into the air passages (40) can be dehumidified by the upwind plates (77). This can reduce the accumulation of frost on the surfaces of the intermediate plates (70), and thus, it is possible to prevent a reduction in heat-transfer rate of the fin (36), and an increase in flow pass resistance of the air passages (40).
  • According to the second aspect of the present invention, the rib (91, 92) can improve the effect of cooling the air, and prevent bending of the upwind plates (77). Since leaning of the upwind plates (77) is prevented as mentioned, the air can flow evenly into the air passages (40). As a result, reliability of the heat exchanger can be ensured.
  • According to the third to fifth aspects of the present invention, heat transfer between the air and the upwind plates (77) can be promoted, and the effect of cooling the air by the upwind plates (77) can be further improved. Further, according to the fifth aspect of the present invention, the tip of the raised portion (95) is in contact with the adjacent upwind plate (77), thereby preventing the upwind plate (77) from leaning horizontally.
  • According to the sixth aspect of the present invention, in the heat exchanger (30) serving as an evaporator, the amount of frost adhering to the intermediate plates (70) facing the air passages (40) can be reduced. Thus, it is possible to reduce the time of the defrosting operation of the heat exchanger (30) for melting the frost, and accordingly extend the time of the heating operation by the reduced period of time. As a result, it is possible to promote energy conservation of the air conditioner.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a refrigerant circuit diagram showing a schematic configuration of an air conditioner having a heat exchanger of an embodiment.
  • FIG. 2 is an oblique view schematically showing the heat exchanger of the embodiment.
  • FIG. 3 is a partial cross-sectional view of the front side of the heat exchanger of the embodiment.
  • FIG. 4 is a cross-sectional view of part of the heat exchanger taken along the line A-A of FIG. 3.
  • FIG. 5 shows a main part of a fin of the heat exchanger of the embodiment. FIG. 5(A) is a front side of the fin. FIG. 5(B) is a cross-sectional view taken along the line B-B of FIG. 5(A).
  • FIG. 6 shows cross-sectional views of the fins of the heat exchanger of the embodiment. FIG. 6(A) is a cross-section taken along the line C-C of FIG. 5. FIG. 6(B) is a cross-section taken along the line D-D of FIG. 5.
    •  DESCRIPTION OF EMBODIMENTS
  • An embodiment of the present invention will be described in detail below, based on the drawings. The following embodiment is merely a preferred example in nature, and is not intended to limit the scope, applications, and use of the invention.
  • A heat exchanger (30) of the embodiment comprises an outdoor heat exchanger (23) of an air conditioner (10) described later.
  • —Air Conditioner—
  • The air conditioner (10) having the heat exchanger (30) of the present embodiment will be described with reference to FIG. 1.
  • <Configuration of Air Conditioner>
  • The air conditioner (10) has an outdoor unit (11) and an indoor unit (12). The outdoor unit (11) and the indoor unit (12) are connected to each other via a liquid communication pipe (13) and a gas communication pipe (14). In the air conditioner (10), a refrigerant circuit (20) is formed by the outdoor unit (11), the indoor unit (12), the liquid communication pipe (13), and the gas communication pipe (14).
  • The refrigerant circuit (20) includes a compressor (21), a four-way valve (22), an outdoor heat exchanger (23), an expansion valve (24), and an indoor heat exchanger (25). The compressor (21), the four-way valve (22), the outdoor heat exchanger (23), and the expansion valve (24) are accommodated in the outdoor unit (11). The outdoor unit (11) is provided with an outdoor fan (15) configured to supply outdoor air to the outdoor heat exchanger (23). The indoor heat exchanger (25) is accommodated in the indoor unit (12). The indoor unit (12) is provided with an indoor fan (16) configured to supply indoor air to the indoor heat exchanger (25).
  • The refrigerant circuit (20) is a closed circuit filled with a refrigerant. In the refrigerant circuit (20), a discharge side of the compressor (21) is connected to a first port of the four-way valve (22), and a suction side of the compressor (21) is connected to a second port of the four-way valve (22). In the refrigerant circuit (20), the outdoor heat exchanger (23), the expansion valve (24), and the indoor heat exchanger (25) are provided sequentially from a third port to a fourth port of the four-way valve (22).
  • The compressor (21) is a scroll type or rotary type hermetic compressor. The four-way valve (22) switches between a first state (the state shown in broken line in FIG. 1) in which the first port communicates with the third port, and the second port communicates with the fourth port, and a second state (the state shown in solid line in FIG. 1) in which the first port communicates with the fourth port, and the second port communicates with the third port. The expansion valve (24) is a so-called electronic expansion valve (24).
  • In the outdoor heat exchanger (23), the outdoor air is heat exchanged with the refrigerant. The outdoor heat exchanger (23) is comprised of the heat exchanger (30) of the present embodiment. In the indoor heat exchanger (25), the indoor air is heat exchanged with the refrigerant. The indoor heat exchanger (25) is comprised of a so-called cross-fin type fin-and-tube heat exchanger having a circular heat-transfer tube.
  • <Cooling Operation>
  • The air conditioner (10) performs a cooling operation. The four-way valve (22) is set to the first state during the cooling operation. The outdoor fan (15) and the indoor fan (16) are driven during the cooling operation.
  • The refrigerant circuit (20) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor (21) passes through the four-way valve (22), flows into the outdoor heat exchanger (23), and dissipates heat to the outdoor air and condenses. The refrigerant flowing out of the outdoor heat exchanger (23) expands when it passes through the expansion valve (24), flows into the indoor heat exchanger (25), and takes heat from the indoor air and evaporates. The refrigerant flowing out of the indoor heat exchanger (25) passes through the four-way valve (22) and is then sucked into the compressor (21) and compressed. The indoor unit (12) supplies air which has been cooled in the indoor heat exchanger (25) to an indoor space.
  • <Heating Operation>
  • The air conditioner (10) performs a heating operation. The four-way valve (22) is set to the second state during the heating operation. The outdoor fan (15) and the indoor fan (16) are driven during the heating operation.
  • The refrigerant circuit (20) performs a refrigeration cycle. Specifically, the refrigerant discharged from the compressor (21) passes the four-way valve (22), flows into the indoor heat exchanger (25), and dissipates heat to the indoor air and condenses. The refrigerant flowing out of the indoor heat exchanger (25) expands when it passes through the expansion valve (24), flows into the outdoor heat exchanger (23), and takes heat from the outdoor air and evaporates. The refrigerant flowing out of the outdoor heat exchanger (23) passes through the four-way valve (22) and is then sucked into the compressor (21) and compressed. The indoor unit (12) supplies air which has been heated in the indoor heat exchanger (25) to an indoor space.
  • <Defrosting Operation>
  • As described above, the outdoor heat exchanger (23) functions as an evaporator in the heating operation. In the operation under low outdoor air temperature conditions, the evaporation temperature of the refrigerant in the outdoor heat exchanger (23) may sometimes be below 0° C. In this case, the moisture in the outdoor air turns into frost and adheres to the outdoor heat exchanger (23). To avoid this, the air conditioner (10) performs a defrosting operation every time a duration of the heating operation reaches a predetermined value (e.g., several tens of minutes), for example.
  • To start the defrosting operation, the four-way valve (22) is switched from the second state to the first state, and the outdoor fan (15) and the indoor fan (16) are stopped. In the refrigerant circuit (20) during the defrosting operation, a high temperature refrigerant discharged from the compressor (21) is supplied to the outdoor heat exchanger (23). The frost adhering to the surface of the outdoor heat exchanger (23) is heated and melted by the refrigerant. The refrigerant which dissipates heat in the outdoor heat exchanger (23) sequentially passes through the expansion valve (24) and the indoor heat exchanger (25), and is then sucked into the compressor (21) and compressed. When the defrosting operation is finished, the heating operation starts again. That is, the four-way valve (22) is switched from the first state to the second state, and the outdoor fan (15) and the indoor fan (16) are driven again.
  • —Heat Exchanger of First Embodiment—
  • The heat exchanger (30) of the present embodiment which comprises the outdoor heat exchanger (23) of the air conditioner (10) will be described with reference to FIGS. 2 to 6.
  • <General Configuration of Heat Exchanger>
  • As shown in FIG. 2 and FIG. 3, the heat exchanger (30) of the present embodiment includes one first header collecting pipe (31), one second header collecting pipe (32), a plurality of flat tubes (33), and a plurality of fins (35). The first header collecting pipe (31), the second header collecting pipe (32), the flat tubes (33), and the fins (35) are all aluminum alloy members, and are attached to one another with solder.
  • Both of the first header collecting pipe (31) and the second header collecting pipe (32) are in an elongated hollow cylindrical shape, with both ends closed. In FIG. 3, the first header collecting pipe (31) is provided upright at the left end of the heat exchanger (30), and the second header collecting pipe (32) is provided upright at the right end of the heat exchanger (30). In other words, the first header collecting pipe (31) and the second header collecting pipe (32) are provided such that their axial directions are vertical.
  • As is also shown in FIG. 4, the flat tube (33) is a heat-transfer tube having a flat oblong cross section or a rectangular cross section with rounded corners. In the heat exchanger (30), the plurality of flat tubes (33) extend in a horizontal direction, and are arranged such that the flat surfaces thereof face each other. Further, the plurality of flat tubes (33) are arranged one above another with a predetermined space between the flat tubes (33). One end of each of the flat tubes (33) is inserted in the first header collecting pipe (31), and the other end of the flat tube (33) is inserted in the second header collecting pipe (32).
  • Each fin (36) is in a plate-like shape, and the fins (36) are arranged in an extension direction of the flat tube (33) with a predetermined space between the fins (36). In other words, the fins (36) are arranged to be substantially orthogonal to the extension direction of the flat tube (33). As will be described in detail later, an area of each fin (36) which is located between vertically adjacent flat tubes (33) comprises an intermediate plate (70).
  • As shown in FIG. 3, in the heat exchanger (30), a space between vertically adjacent flat tubes (33) is divided into a plurality of air passages (40) by the intermediate plates (70) of the fins (36). In the heat exchanger (30), the refrigerant flowing in the fluid passages (34) of the flat tube (33) exchanges heat with the air flowing in the air passages (40).
  • <Configuration of Fin>
  • As shown in FIG. 4 and FIG. 5, each of the fins (36) is a vertically elongate plate-like fin formed by pressing a metal plate. The thickness of each fin (36) is approximately 0.1 mm.
  • The fin (36) is provided with a plurality of elongate cutouts (45) each extending in a width direction (i.e., in an air passage direction) of the fin (36) from a leading edge (38) of the fin (36). The plurality of cutouts (45) are formed in the fin (36) at predetermined intervals in a longitudinal direction (i.e., a vertical direction) of the fin (36). Of the cutout (45), a portion between the intermediate plates (70) of the fins (36) comprises a tube insertion portion (46). The flat tube (33) is inserted in the tube insertion portion (46) from the open upwind side, and is held. The width of the tube insertion portion (46) in the vertical direction is substantially equal to the width of the thickness of the flat tube (33), and the length of the tube insertion portion (46) is substantially equal to the width of the flat tube (33).
  • The flat tube (33) is inserted in the tube insertion portion (46) of the fin (36) from the leading edge (38) of the fin (36). The flat tube (33) is attached to the periphery of the tube insertion portion (46) with solder. That is, the flat tube (33) is fitted to the periphery of the tube insertion portion (46) which is part of the cutout (45).
  • The fin (36) includes a plurality of intermediate plates (70) in areas between vertically adjacent flat tubes (33), a downwind plate (75) provided on the downwind side of the intermediate plates (70), and an upwind plate (77) provided on the upwind side of each of the plurality of intermediate plates (70). The intermediate plates (70) divide the space between vertically adjacent flat tubes (33) into the air passages (40). That is, the intermediate plates (70) face the air passages (40). The downwind plate (75) is continuous with the downwind ends of all the intermediate plates (70) arranged one above another. Each of the upwind plate (77) projects from a middle portion in the vertical direction of the upwind end of each intermediate plate (70) toward the upwind side. The height of each upwind plate (77) is smaller than the height of each intermediate plate (70), and the width of the upwind plate (77) is narrower than the width of the intermediate plate (70).
  • The fin (36) is provided with louvers (50 a, 50 b) and protrusions (81-83). In the fin (36), the protrusions (81-83) are located upwind of the louvers (50 a, 50 b). The numbers of the protrusions (81-83) and the louvers (50 a, 50 b) described below are merely examples.
  • Specifically, the fin (36) is provided with three protrusions (81-83) in an upwind side area. The three protrusions (81-83) are arranged side by side in the air passage direction (i.e., the direction from the leading edge (38) to the trailing edge (39) of the fin (36)). That is, the fin (36) is provided with a first protrusion (81), a second protrusion (82), and a third protrusion (83) sequentially from the upwind side to the downwind side. In the fin (36), the first protrusion (81) lies across the upwind plate (77) and the intermediate plate (70), and the second protrusion (82) and the third protrusion (83) are provided on the intermediate plate (70).
  • Each of the protrusions (81-83) has an inverted V shape formed by making the fin (36) protrude toward the air passage (40). The three protrusions (81-83) protrude to the same direction. In the fin (36) of the present embodiment, the protrusions (81-83) protrude to the right when viewed from the leading edge (38) of the fin (36). Ridges (81 a, 82 a, 83 a) of the protrusions (81-83) (i.e., the line on the tip of each protrusion in the inverted V shape) are substantially in parallel with the leading edge (38) of the fin (36). That is, the ridges (81 a, 82 a, 83 a) of the protrusions (81-83) intersect with the airflow direction in the air passage (40).
  • As shown in FIG. 5(B), the height H1 of the first protrusion (81) in the protrusion direction, the height H2 of the second protrusion (82) in the protrusion direction, and the height H3 of the third protrusion (83) in the protrusion direction are equal (H1=H2=H3). As shown in FIG. 5(A), the width W1 of the first protrusion (81) in the air passage direction is smaller than the width W2 of the second protrusion (82) in the air passage direction, and the width W3 of the third protrusion (83) is smaller than the width W1 of the first protrusion (81) in the air passage direction (W1<W2<W3).
  • The intermediate plate (70) of the fin (36) is provided with a group of louvers (50 a, 50 b) at the downwind side of the protrusions (81-83). The louvers (50 a, 50 b) are obtained by giving a plurality of slit-like cuts in the intermediate plate (70) and plastically deforming a portion between adjacent cuts as if twisting the portion. The longitudinal direction of each louver (50 a, 50 b) is substantially parallel to the leading edge (38) of the fin (36) (i.e., the vertical direction). That is, the longitudinal direction of each louver (50 a, 50 b) intersects with the air passage direction. The lengths of the louvers (50 a, 50 b) are equal to each other.
  • As shown in FIG. 5(B), the louvers (50 a, 50 b) are tilted with respect to their peripheral flat portions. Specifically, bent-out ends (53 a, 53 b) on the upwind side of the louvers (50 a, 50 b) protrude to the left when viewed from the leading edge (38) of the fin (36). On the other hand, bent-out ends (53 a, 53 b) of the louvers (50 a, 50 b) on the downwind side protrude to the right when viewed from the leading edge (38) of the fin (36).
  • As shown in FIGS. 6(A) and 6(B), each of the bent-out ends (53 a, 53 b) of the louvers (50 a, 50 b) includes a main edge (54 a, 54 b), an upper edge (55 a, 55 b), a lower edge (56 a, 56 b). The main edge (54 a, 54 b) extends substantially in parallel with the leading edge (38) of the fin (36). The upper edge (55 a, 55 b) extends from the upper end of the main edge (54 a, 54 b) to the upper end of the louver (50 a, 50 b), and is tilted with respect to the main edge (54 a, 54 b). The lower edge (56 a, 56 b) extends from the lower end of the main edge (54 a, 54 b) to the lower end of the louver (50 a, 50 b), and is tilted relative to the main edge (54 a, 54 b).
  • As shown in FIG. 5(A) and FIG. 6(A), in each of the plurality of louvers (50 a) located on the upwind side, a tilt angle θ2 of the lower edge (56 a) with respect to the main edge (54 a) is smaller than a tilt angle θ1 of the upper edge (55 a) with respect to the main edge (54 a) (i.e., θ2<θ1). Thus, in each louver (50 a), the lower edge (56 a) is longer than the upper edge (55 a). The upwind side louver (50 a) is an asymmetric louver in which the shape of the bent-out end (53 a) is asymmetric in the vertical direction.
  • On the other hand, as shown in FIG. 5(A) and FIG. 6(B), in each of the plurality of louvers (50 b) located on the downwind side, a tilt angle θ4 of the lower edge (56 b) with respect to the main edge (54 b) is equal to a tilt angle θ3 of the upper edge (55 b) with respect to the main edge (54 b) (i.e., θ4=θ3). The louver (50 b) is a symmetric louver in which the shape of the bent-out end (53 b) is symmetric in the vertical direction. The tilt angle θ3 of the upper edge (55 b) of the downwind side louver (50 b) is equal to the tilt angle θ1 of the upper edge (55 a) of the upwind side louver (50 a) (i.e., θ3=θ1).
  • As shown in FIG. 5(A), the length L1 from the upper ends of the second protrusion (82) and the third protrusion (83) to the upper end of the intermediate plate (70), the length L2 from the lower ends of the second protrusion (82) and the third protrusion (83) to the lower end of the intermediate plate (70), the length L3 from the upper ends of the louvers (50 a, 50 b) to the upper end of the intermediate plate (70), and the length L4 from the lower ends of the louvers (50 a, 50 b) to the lower end of the intermediate plate (70) are the same.
  • In each fin (36), one auxiliary protrusion (85) lies across the intermediate plate (70) and the downwind plate (75).
  • The auxiliary protrusion (85) has an inverted V shape formed by making the fin (36) protrude. In the fin (36) of the present embodiment, each auxiliary protrusion (85) protrudes to the right when viewed from the leading edge (38) of the fin (36). The ridge (85 a) of the auxiliary protrusion (85) is substantially in parallel with the leading edge (38) of the fin (36). That is, the ridge (85 a) of the auxiliary protrusion (85) intersects with the airflow direction in the air passage (40). In addition, the lower end of the auxiliary protrusion (85) is tilted downward toward the downwind side.
  • As shown in FIG. 5(B), the height H5 of the auxiliary protrusion (85) in the protrusion direction is smaller than the heights H1, H2, H3 of the first to third protrusions (81, 82, 83) (H5<H1=H2=H3). As shown in FIG. 5(A), the width W5 of the auxiliary protrusion (85) in the air passage direction is smaller than the width W3 of the third protrusion (83) in the air passage direction (W5<W3).
  • The downwind plate (75) of the fin (36) is provided with a vertically extending water-conducting rib (49), a plurality of downwind tabs (48) arranged in the vertical direction, and a plurality of downwind protrusions (84) each provided between vertically adjacent downwind tabs (48).
  • The water-conducting rib (49) is an elongated recessed groove extending vertically along the trailing edge (39) of the fin (36). The water-conducting rib (49) extends from the upper end to the lower end of the downwind plate (75) of the fin (36).
  • Each of the downwind tabs (48) is a small rectangular piece formed by cutting and bending the fin (36). The downwind tabs (48) keep a space between the fins (36), with the tips thereof being in contact with their adjacent fin (36).
  • Each downwind protrusion (84) has an inverted V shape formed by making the downwind plate (75) protrude. In the fin (36) of the present embodiment, each downwind protrusion (84) protrudes to the right when viewed from the leading edge (38) of the fin (36). Ridges (84 a) of the downwind protrusions (84) are substantially in parallel with the leading edge (38) of the fin (36). That is, the ridges (84 a) of the downwind protrusions (84) intersect with the airflow direction in the air passage (40).
  • As shown in FIG. 5(B), the height H4 of the downwind protrusion (84) in the protrusion direction is equal to the heights H1, H2, H3 of the first to third protrusions (81, 82, 83) (H4=H1=H2=H3). As shown in FIG. 5(A), the width W4 of the downwind protrusion (84) in the air passage direction is equal to the width W2 of the second protrusion (82) in the air passage direction (W4=W2).
  • The fin (36) is provided with two horizontal ribs (91, 92), and the above-described first protrusion (81) which lie across the upwind plate (77) and the intermediate plate (70).
  • The first protrusion (81) comprises an intermediate heat-transfer portion provided at a middle portion, in the vertical direction, of the upwind plate (77). The first protrusion (81) comprises an upwind side heat-transfer portion which promotes heat transfer between the fin (36) and air on the upwind side of the intermediate plate (70).
  • In each fin (36), the upper horizontal rib (91) is provided at an area on the upper side of the first protrusion (81) and the upwind tab (95), and the lower horizontal rib (92) is provided at an area on the lower side of the first protrusion (81) and the upwind tab (95). The horizontal ribs (91, 92) are comprised of raised lines which protrude toward the air passage (40). The direction to which the horizontal ribs (91, 92) protrude is the same as the protrusion direction of the protrusions (81, 82, 83, 84). The upper horizontal rib (91) extends horizontally from the leading edge (38) of the fin (36) to an upper portion of the second protrusion (82). The lower horizontal rib (92) extends horizontally from the leading edge (38) of the fin (36) to a lower portion of the second protrusion (82). That is, in the fin (36), the two horizontal ribs (91, 92) extend linearly in the protruding direction of the upwind plates (77) (i.e., in the air passage direction). The horizontal ribs (91, 92) comprise reinforcing ribs which prevent the upwind plate (77) from being bent toward the air passage (40) with respect to the intermediate plate (70) of the fin (36). The horizontal ribs (91, 92) also comprise upwind side heat-transfer portions which promote heat transfer between the fin (36) and air on the upwind side of the intermediate plate (70).
  • The upwind tab (95) as a raised portion is provided on the front side of each of the upwind plates (77). The upwind tab (95) comprises an intermediate heat-transfer portion provided at a middle portion, in the vertical direction, of the upwind plate (77). The upwind tab (95) is a small rectangular piece formed by cutting and bending the fin (36) so as to protrude in a thickness direction of the fin (36). The front surface of the upwind tab (95) is tilted obliquely downward with respect to the air passage direction (i.e., the horizontal direction). Thus, an airflow resistance of the heat exchanger (30) can be reduced, compared to the case in which the front surface of the upwind tab (95) is vertical. The upwind tab (95) keeps a space between the fins (36), with the tips thereof being in contact with the adjacent fin (36). The upwind tab (95) also comprises an upwind side heat-transfer portion which promotes heat transfer between the fin (36) and air on the upwind side of the intermediate plate (70).
  • —Reduction of Frost Adhering on Surfaces of Fins—
  • As described above, the outdoor heat exchanger (23) of the present embodiment functions as an evaporator in the heating operation. In the heat exchanger (30) in the heating operation, the evaporation temperature of the refrigerant may sometimes be below 0° C., and frost may adhere to the surface of the fin (36). In the heat exchanger (30) of the present embodiment, the air before flowing into the air passage (40) is cooled/dehumidified by the upwind plates (77), thereby reducing the accumulation of frost on the inner side of the air passage (40).
  • Specifically, the air which has been transferred by the outdoor fan (15) and flowed into the heat exchanger (30) flows to the downwind side along each of the upwind plates (77). The air flowing on lateral sides of the upwind plates (77) contacts the upwind tab (95) and the first protrusion (81), and is cooled. The air which has flowed around the upwind tab (95) and the first protrusion (81) and moved to the upper side or the lower side of the upwind tab (95) and the first protrusion (81) contacts the horizontal ribs (91, 92), and is cooled. Thus, in the fin (36), the upwind tab (95), the first protrusion (81), and the horizontal ribs (91, 92) comprise heat-transfer promotion portions which promote heat transfer between air and the upwind plates (77).
  • When the air is cooled by the upwind plates (77) to a temperature equal to or lower than a dew point, moisture in the air is condensed. When the air is cooled by the upwind plates (77) to a temperature equal to or lower than 0° C., moisture in the air is frozen, and frost adheres to the surfaces of the upwind plates (77). Thus, on the lateral sides of the upwind plates (77), moisture in the air is condensed or turns into frost, thereby dehumidifying the air.
  • The air dehumidified on the lateral sides of the upwind plates (77) flows to the air passages (40) partitioned by the intermediate plates (70). The intermediate plates (70) are relatively close to the flat tubes (33), and thus, the air flowing in the air passages (40) is cooled rapidly. However, this air has been dehumidified before flowing into the air passages (40), and therefore, the accumulation of frost on the surfaces of the intermediate plates (70) is reduced.
    • Advantages of Embodiment
  • In the above embodiment, the upwind plates (77) extend from the intermediate plates (70) of the fin (36) toward the upwind side. Thus, the air before flowing into the air passages (40) can be cooled and dehumidified. Moreover, since each of the upwind plates (77) is provided with the upwind tab (95), the first protrusion (81), and the horizontal ribs (91, 92), it is possible to promote heat transfer between the air and the upwind plates (77), and improve the effect of dehumidifying the air. By dehumidifying the air before flowing into the air passages (40) in the manner as described above, the accumulation of frost on the surfaces of the intermediate plates (70) is reduced. As a result, it is possible to prevent a reduction in heat-transfer rate of the fin (36) and an increase in flow pass resistance of the air passages (40) due to accumulation of frost.
  • Since the accumulation of frost on the intermediate plates (70) is reduced as described above, it is possible to reduce the time of the above-mentioned defrosting operation. As a result, it is possible to extend the time of the heating operation, and promote energy conservation.
  • Further, the two horizontal ribs (91, 92) provided on each of the upwind plates (77) prevent the upwind plates (77) from being bent in the horizontal direction with respect to the intermediate plate (70). Such bending of the upwind plates (77) can be further prevented by the upwind tab (95) whose tip is brought into contact with the adjacent fin (36).
    • Other Embodiments
  • In the upwind plates (77) of the above embodiment, any of the upwind tab (95), the first protrusion (81), and the two horizontal ribs (91, 92) may be omitted. Further, each of the upwind plates (77) may be provided with the louvers (50 a, 50 b) of the above embodiment, and the louvers (50 a, 50 b) may be used as upwind side heat-transfer portions (raised portions).
    • INDUSTRIAL APPLICABILITY
  • As described above, the present invention is useful for a heat exchanger having a flat tube and a fin, and configured to exchange heat between a fluid flowing in the flat tube and air.
    • DESCRIPTION OF REFERENCE CHARACTERS
      • 10 air conditioner
      • 20 refrigerant circuit
      • 30 heat exchanger
      • 33 flat tube
      • 36 fin
      • 38 leading edge
      • 40 air passage
      • 46 tube insertion portion
      • 70 intermediate plate
      • 75 downwind plate
      • 77 upwind plate
      • 81 first protrusion (upwind side heat-transfer portion, intermediate heat-transfer portion)
      • 91 upper horizontal rib (upwind side heat-transfer portion)
      • 92 lower horizontal rib (upwind side heat-transfer portion)
      • 95 upwind tab (upwind side heat-transfer portion, raised portion, intermediate heat-transfer portion)

Claims (15)

1. A heat exchanger, comprising:
a plurality of flat tubes arranged one above another such that flat surfaces thereof face each other; and
a plurality of vertically extending, plate-like fins arranged in an extension direction of the flat tubes, wherein
each of the fins includes
a plurality of intermediate plates arranged one above another and dividing a space between adjacent ones of the flat tubes into air passages,
a plurality of tube insertion portions each provided between vertically adjacent ones of the intermediate plates, with an upwind side thereof being open such that a corresponding one of the flat tubes is inserted therein,
a vertically extending downwind plate that is continuous with downwind ends of the plurality of intermediate plates arranged one above another, and
a plurality of upwind plates extending further toward an upwind side than the flat tubes from upwind side ends of the intermediate plates, and
each of the upwind plates is provided with at least one upwind side heat-transfer portion which projects in a thickness direction of the fins.
2. The heat exchanger of claim 1, wherein
the upwind side heat-transfer portion includes a rib which extends in a protruding direction of the upwind plates.
3. The heat exchanger of claim 2, wherein
the upwind side heat-transfer portion includes an intermediate heat-transfer portion provided at a middle portion, in a vertical direction, of each of the upwind plates, and the rib provided on at least one of an upper side or a low side of the intermediate heat-transfer portion.
4. The heat exchanger of claim 1, wherein
the upwind side heat-transfer portion includes a protrusion which extends in a direction orthogonal to an air passage direction.
5. The heat exchanger of claim 1, wherein
the upwind side heat-transfer portion includes a raised portion formed by cutting and bending part of the fin.
6. An air conditioner, comprising a refrigerant circuit including the heat exchanger of claim 1, wherein
the refrigerant circuit performs a refrigeration cycle by circulating a refrigerant.
7. The heat exchanger of claim 2, wherein
the upwind side heat-transfer portion includes a protrusion which extends in a direction orthogonal to an air passage direction.
8. The heat exchanger of claim 3, wherein
the upwind side heat-transfer portion includes a protrusion which extends in a direction orthogonal to an air passage direction.
9. The heat exchanger of claim 2, wherein
the upwind side heat-transfer portion includes a raised portion formed by cutting and bending part of the fin.
10. The heat exchanger of claim 3, wherein
the upwind side heat-transfer portion includes a raised portion formed by cutting and bending part of the fin.
11. The heat exchanger of claim 4, wherein
the upwind side heat-transfer portion includes a raised portion formed by cutting and bending part of the fin.
12. An air conditioner, comprising a refrigerant circuit including the heat exchanger of claim 2, wherein
the refrigerant circuit performs a refrigeration cycle by circulating a refrigerant.
13. An air conditioner, comprising a refrigerant circuit including the heat exchanger of claim 3, wherein
the refrigerant circuit performs a refrigeration cycle by circulating a refrigerant.
14. An air conditioner, comprising a refrigerant circuit including the heat exchanger of claim 4, wherein
the refrigerant circuit performs a refrigeration cycle by circulating a refrigerant.
15. An air conditioner, comprising a refrigerant circuit including the heat exchanger of claim 5, wherein
the refrigerant circuit performs a refrigeration cycle by circulating a refrigerant.
US13/980,584 2011-01-21 2012-01-23 Heat exchanger and air conditioner Abandoned US20130299152A1 (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016010389A1 (en) * 2014-07-17 2016-01-21 엘지전자 Heat exchanger and heat pump having same
US20180010857A1 (en) * 2015-03-31 2018-01-11 Gd Midea Heating & Ventilating Equipment Co., Ltd. Heat exchanger and multi-split system having same
US20180224210A1 (en) * 2017-02-03 2018-08-09 Samsung Electronics Co., Ltd. Heat exchanger and method of manufacturing the same
US20190120557A1 (en) * 2016-04-13 2019-04-25 Daikin Industries, Ltd. Heat exchanger
US10578375B2 (en) * 2015-09-21 2020-03-03 Sanhua (Hangzhou) Micro Channel Heat Exchanger Co., Ltd. Fin and heat exchanger having same

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140042093A (en) * 2012-09-27 2014-04-07 삼성전자주식회사 Heat exchanger
JP2014149131A (en) * 2013-02-01 2014-08-21 Mitsubishi Electric Corp Outdoor unit, and refrigeration cycle device
KR20140142802A (en) * 2013-06-04 2014-12-15 삼성전자주식회사 Outdoor heat exchanger and air conditioner
JP6153785B2 (en) * 2013-06-27 2017-06-28 三菱重工業株式会社 Heat exchanger
KR102174510B1 (en) * 2013-11-05 2020-11-04 엘지전자 주식회사 Refrigeration cycle of refrigerator
US10197313B2 (en) * 2014-05-09 2019-02-05 Samwon Industrial Co., Ltd. Condenser for refrigerator
JP6036788B2 (en) * 2014-10-27 2016-11-30 ダイキン工業株式会社 Heat exchanger
JP5962734B2 (en) * 2014-10-27 2016-08-03 ダイキン工業株式会社 Heat exchanger
US20180100659A1 (en) * 2015-03-30 2018-04-12 Mitsubishi Electric Corporation Heat exchanger and air-conditioning apparatus
JP2017083041A (en) * 2015-10-26 2017-05-18 株式会社富士通ゼネラル Heat exchanger
JP6380449B2 (en) * 2016-04-07 2018-08-29 ダイキン工業株式会社 Indoor heat exchanger
JP2019052824A (en) * 2017-09-19 2019-04-04 サンデンホールディングス株式会社 Heat exchanger
CN109186304A (en) * 2018-09-30 2019-01-11 珠海格力电器股份有限公司 Fin and heat exchanger with same
CN109186303B (en) * 2018-09-30 2020-01-03 珠海格力电器股份有限公司 Fin and heat exchanger with same
CN109405354A (en) * 2018-11-19 2019-03-01 珠海格力电器股份有限公司 Falling film type heat exchanger and air conditioning unit
KR20200078936A (en) * 2018-12-24 2020-07-02 삼성전자주식회사 Heat exchanger
JP2020159616A (en) * 2019-03-26 2020-10-01 株式会社富士通ゼネラル Air conditioner
WO2021001953A1 (en) * 2019-07-03 2021-01-07 三菱電機株式会社 Heat exchanger and refrigeration cycle device
JP7457587B2 (en) * 2020-06-18 2024-03-28 三菱重工サーマルシステムズ株式会社 Heat exchangers, heat exchanger units, and refrigeration cycle equipment

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2428145A (en) * 1944-09-11 1947-09-30 Pacific Metals Company Ltd Heat transfer fin
US3309763A (en) * 1962-12-20 1967-03-21 Borg Warner Method for making a heat exchanger
US5207270A (en) * 1990-10-22 1993-05-04 Matsushita Electric Industrial Co., Ltd. Fin-tube heat exchanger
EP0769669A1 (en) * 1995-10-17 1997-04-23 Norsk Hydro Technology B.V. Heat exchanger
US5642777A (en) * 1995-01-23 1997-07-01 Lg Electronics Inc. Fin tube heat exchanger
JP2000234883A (en) * 1999-02-17 2000-08-29 Showa Alum Corp Heat exchanger
US20020134537A1 (en) * 2001-02-07 2002-09-26 Stephen Memory Heat exchanger
WO2003046458A1 (en) * 2001-11-27 2003-06-05 Valeo Thermique Moteur Heat exchanger module fin
FR2872891A1 (en) * 2004-07-12 2006-01-13 Valeo Thermique Moteur Sas Heat exchanging device for motor vehicle, has heat exchanging vanes presenting plane portion with two flow deflectors that are made in form of blades obliquely projecting from portion and placed parallel to portion, respectively
US7111670B2 (en) * 2002-12-25 2006-09-26 T. Rad Co., Ltd. Plate fin for heat exchanger and heat exchanger core
US7578339B2 (en) * 2003-05-23 2009-08-25 Mitsubishi Denki Kabushiki Kaisha Heat exchanger of plate fin and tube type
GB2466687A (en) * 2009-01-05 2010-07-07 Mitsubishi Electric Corp Heat exchanger and method of manufacturing a heat exchanger

Family Cites Families (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3167046A (en) * 1956-01-24 1965-01-26 Modine Mfg Co Method of forming a sheet metal fin strip element for heat exchange structures
FR1480185A (en) * 1966-03-09 1967-05-12 Chausson Usines Sa Heating radiator for vehicle
JPS4884947A (en) * 1972-02-16 1973-11-10
JPS60174495A (en) * 1984-10-03 1985-09-07 Hitachi Ltd Heat exchanger for air conditioner
JPH0271096A (en) * 1988-09-05 1990-03-09 Matsushita Refrig Co Ltd Heat exchanger with fin
JP2624336B2 (en) * 1989-06-28 1997-06-25 松下冷機株式会社 Finned heat exchanger
JPH0363499A (en) * 1989-07-31 1991-03-19 Matsushita Refrig Co Ltd Heat exchanger with fins
JP2735310B2 (en) * 1989-09-08 1998-04-02 株式会社東芝 Heat exchanger
JPH0590173U (en) 1992-04-20 1993-12-07 住友軽金属工業株式会社 Fin tube heat exchanger
JP3264525B2 (en) * 1992-10-12 2002-03-11 東芝キヤリア株式会社 Heat exchanger
JPH06221787A (en) * 1993-01-29 1994-08-12 Nippondenso Co Ltd Heat exchanger
JPH06300474A (en) * 1993-04-12 1994-10-28 Daikin Ind Ltd Heat exchanger with fin
JP3061537B2 (en) * 1994-09-16 2000-07-10 アネスト岩田株式会社 Paint sludge collection system for wet coating room
JP3942210B2 (en) * 1996-04-16 2007-07-11 昭和電工株式会社 Heat exchanger, room air conditioner and car air conditioner using this heat exchanger
US5752567A (en) * 1996-12-04 1998-05-19 York International Corporation Heat exchanger fin structure
JPH10339594A (en) * 1997-06-09 1998-12-22 Toshiba Corp Heat exchanger
JP2002031434A (en) * 2000-07-19 2002-01-31 Fujitsu General Ltd Heat exchanger for air conditioner
JP4096226B2 (en) 2002-03-07 2008-06-04 三菱電機株式会社 FIN TUBE HEAT EXCHANGER, ITS MANUFACTURING METHOD, AND REFRIGERATION AIR CONDITIONER
JP2004251554A (en) * 2003-02-20 2004-09-09 Matsushita Electric Ind Co Ltd Exterior heat exchanger for heat pump
WO2005010442A1 (en) * 2003-07-28 2005-02-03 Matsushita Electric Industrial Co., Ltd. Air conditioner
WO2006004137A1 (en) 2004-07-05 2006-01-12 Showa Denko K.K. Evaporator
JP2006170601A (en) * 2004-07-05 2006-06-29 Showa Denko Kk Evaporator
JP2006153327A (en) * 2004-11-26 2006-06-15 Daikin Ind Ltd Heat exchanger
JP2007232246A (en) 2006-02-28 2007-09-13 Denso Corp Heat exchanger
JP5084304B2 (en) * 2007-03-06 2012-11-28 三菱電機株式会社 Finned tube heat exchanger and refrigeration cycle
JP4679542B2 (en) * 2007-03-26 2011-04-27 三菱電機株式会社 Finned tube heat exchanger, heat exchanger unit using the same, and air conditioner
CN201141739Y (en) * 2007-11-23 2008-10-29 北京龙源冷却技术有限公司 Single-row finned tube radiator
JP2009281693A (en) * 2008-05-26 2009-12-03 Mitsubishi Electric Corp Heat exchanger, its manufacturing method, and air-conditioning/refrigerating device using the heat exchanger
JP4845943B2 (en) 2008-08-26 2011-12-28 三菱電機株式会社 Finned tube heat exchanger and refrigeration cycle air conditioner
CN201311227Y (en) * 2008-11-14 2009-09-16 上虞市春晖风冷设备有限公司 Cooling fin of air cooler

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2428145A (en) * 1944-09-11 1947-09-30 Pacific Metals Company Ltd Heat transfer fin
US3309763A (en) * 1962-12-20 1967-03-21 Borg Warner Method for making a heat exchanger
US5207270A (en) * 1990-10-22 1993-05-04 Matsushita Electric Industrial Co., Ltd. Fin-tube heat exchanger
US5642777A (en) * 1995-01-23 1997-07-01 Lg Electronics Inc. Fin tube heat exchanger
EP0769669A1 (en) * 1995-10-17 1997-04-23 Norsk Hydro Technology B.V. Heat exchanger
JP2000234883A (en) * 1999-02-17 2000-08-29 Showa Alum Corp Heat exchanger
US20020134537A1 (en) * 2001-02-07 2002-09-26 Stephen Memory Heat exchanger
US7032313B2 (en) * 2001-02-07 2006-04-25 Modine Manufacturing Company Method of fabricating a heat exchanger
WO2003046458A1 (en) * 2001-11-27 2003-06-05 Valeo Thermique Moteur Heat exchanger module fin
US7111670B2 (en) * 2002-12-25 2006-09-26 T. Rad Co., Ltd. Plate fin for heat exchanger and heat exchanger core
US7578339B2 (en) * 2003-05-23 2009-08-25 Mitsubishi Denki Kabushiki Kaisha Heat exchanger of plate fin and tube type
FR2872891A1 (en) * 2004-07-12 2006-01-13 Valeo Thermique Moteur Sas Heat exchanging device for motor vehicle, has heat exchanging vanes presenting plane portion with two flow deflectors that are made in form of blades obliquely projecting from portion and placed parallel to portion, respectively
GB2466687A (en) * 2009-01-05 2010-07-07 Mitsubishi Electric Corp Heat exchanger and method of manufacturing a heat exchanger

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016010389A1 (en) * 2014-07-17 2016-01-21 엘지전자 Heat exchanger and heat pump having same
KR20160009974A (en) * 2014-07-17 2016-01-27 엘지전자 주식회사 Heat Exchanger and Heat Pump having the same
US20170198954A1 (en) * 2014-07-17 2017-07-13 Lg Electronics Inc. HEAT EXCHANGER AND HEAT PUMP HAVING THE SAME (As Amended)
US10126030B2 (en) * 2014-07-17 2018-11-13 Lg Electronics Inc. Heat exchanger and heat pump having the same
KR102203435B1 (en) * 2014-07-17 2021-01-14 엘지전자 주식회사 Heat Exchanger and Heat Pump having the same
US20180010857A1 (en) * 2015-03-31 2018-01-11 Gd Midea Heating & Ventilating Equipment Co., Ltd. Heat exchanger and multi-split system having same
US10578375B2 (en) * 2015-09-21 2020-03-03 Sanhua (Hangzhou) Micro Channel Heat Exchanger Co., Ltd. Fin and heat exchanger having same
US20190120557A1 (en) * 2016-04-13 2019-04-25 Daikin Industries, Ltd. Heat exchanger
US10801784B2 (en) * 2016-04-13 2020-10-13 Daikin Industries, Ltd. Heat exchanger with air flow passage for exchanging heat
US20180224210A1 (en) * 2017-02-03 2018-08-09 Samsung Electronics Co., Ltd. Heat exchanger and method of manufacturing the same
US11079180B2 (en) * 2017-02-03 2021-08-03 Samsung Electronics Co., Ltd. Heat exchanger and method of manufacturing the same

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