Technical Field
[0001] The present invention relates to a stacking header, a heat exchanger, and an air-conditioning
apparatus according to the wording of claims 1, 7 and 9, respectively.
Background Art
[0002] Some of existing stacking headers include a first plate unit having a plurality of
outlet flow paths, and a second plate unit stacked on the first plate unit and having
a distribution flow path for distributing refrigerant to the plurality of outlet flow
paths (see, for example, Patent Literature 1).
Citation List
Patent Literature
[0003] Patent Literature 1: Japanese Unexamined Patent Application Publication No.
6-11291 (Paragraphs [0012] to [0028], Fig. 1 to Fig. 9)
WO 2013/160954 discloses a stacking header according to the preamble of claim 1.
Summary of Invention
Technical Problem
[0004] Such an existing stacking header has a single row of outlet flow paths. Thus, for
example, when the stacking header is employed for an apparatus such as a heat exchanger
including a plurality of heat exchange units aligned in an airflow direction, the
refrigerant flowing out of each of the outlet flow paths has to be branched into a
plurality of rows in a part of the apparatus other than the stacking header using
pipes or other components, leading to complication of the structure of the apparatus
for which the stacking header is employed.
[0005] The present invention has been accomplished in view of the foregoing problem, and
provides a stacking header that eases the complication of the structure of the apparatus
for which the stacking header is employed. The present invention also provides a heat
exchanger including such a stacking header. Further, the present invention provides
an air-conditioning apparatus including such a heat exchanger. Solution to Problem
[0006] The present invention provides a stacking header as set forth in claim 1. Advantageous
Effects of Invention
[0007] The stacking header according to the embodiment of the present invention includes
the first plate unit having the first inlet flow path and the first outlet flow path,
the second plate unit attached to the first plate unit and having at least a part
of the first passing flow path for refrigerant flowing from the first inlet flow path
to pass through and at least a part of the second passing flow path for refrigerant
to pass through to the first outlet flow path, and the first pipe connecting the end
portion of the first passing flow path not communicating with the first inlet flow
path and the end portion of the second passing flow path not communicating with the
first outlet flow path, to constitute the first turnback flow path. Such a configuration
eliminates the need to employ pipes or other components to branch the refrigerant
into a plurality of rows in the part of the apparatus other than the stacking header,
thereby easing the complication of the structure of the apparatus for which the stacking
header is employed.
Brief Description of Drawings
[0008]
Fig. 1 is a perspective view of a heat exchanger according to Embodiment 1.
Fig. 2 is an exploded perspective view of a first-row divisional unit and associated
components, in the heat exchanger according to Embodiment 1.
Fig. 3 is an exploded perspective view of a second-row divisional unit and associated
components, in the heat exchanger according to Embodiment 1.
Fig. 4 is a block diagram showing a configuration of an air-conditioning apparatus
including the heat exchanger according to Embodiment 1.
Fig. 5 is another block diagram showing the configuration of the air-conditioning
apparatus including the heat exchanger according to Embodiment 1.
Fig. 6 is a schematic cross-sectional view for explaining the details of a first passing
flow path and a second passing flow path of the heat exchanger according to Embodiment
1.
Fig. 7 is a graph showing a relationship between a flow path length L2 and uniformity
of refrigerant, realized when the heat exchanger according to Embodiment 1 acts as
evaporator.
Fig. 8 is a graph showing a relationship between a flow path length L1 and uniformity
of refrigerant, realized when the heat exchanger according to Embodiment 1 acts as
condenser.
Fig. 9 is a perspective view of a heat exchanger according to Embodiment 2.
Fig. 10 is an exploded perspective view of a third-row divisional unit and associated
components, in the heat exchanger according to Embodiment 2.
Fig. 11 is a perspective view of a heat exchanger according to Embodiment 3.
Fig. 12 is an exploded perspective view of a second-row divisional unit and associated
components, in the heat exchanger according to Embodiment 3. Description of Embodiments
[0009] Hereafter, a stacking header according to the present invention will be described
with reference to the drawings.
[0010] Configurations described hereafter are merely exemplary, and the configurations of
the stacking header according to the present invention are not limited to the description
given hereafter. In the drawings, the same or similar components will be given the
same reference signs, or may be cited without the reference signs. Minor details of
the configuration may be simplified or omitted, as the case may be. Descriptions of
the same or similar configurations may be simplified or omitted, as the case may be.
[0011] Although the stacking header according to the present invention is utilized to distribute
refrigerant flowing into a heat exchanger in the following description, the stacking
header according to the present invention may be employed to distribute the refrigerant
flowing into a different apparatus. Although the heat exchanger including the stacking
header according to the present invention is employed in an air-conditioning apparatus
in the following description, the heat exchanger is not limited to the configuration.
The heat exchanger may be incorporated in another refrigeration cycle apparatus having
a refrigerant circuit. Further, although the heat exchanger including the stacking
header according to the present invention is an outdoor heat exchanger of the air-conditioning
apparatus in the following description, the heat exchanger is not limited to the configuration.
The heat exchanger may be an indoor heat exchanger of the air-conditioning apparatus.
In addition, although the air-conditioning apparatus is configured to switch between
a heating operation and a cooling operation in the following description, the air-conditioning
apparatus is not limited to the configuration. The air-conditioning apparatus may
be configured to perform only either of the heating operation and the cooling operation.
Embodiment 1
[0012] The heat exchanger according to Embodiment 1 will be described.
< Configuration of Heat Exchanger >
[0013] Hereafter, a configuration of the heat exchanger according to Embodiment 1 will be
described.
(General Configuration of Heat Exchanger)
[0014] Hereafter, a general configuration of the heat exchanger according to Embodiment
1 will be described.
[0015] Fig. 1 is a perspective view of the heat exchanger according to Embodiment 1.
[0016] As shown in Fig. 1, the heat exchanger 1 includes a heat exchange unit 2 and a stacking
header 3.
[0017] The heat exchange unit 2 includes a first-row heat exchange unit 21 located on the
windward side in the flow direction of air passing through the heat exchange unit
2 (blank arrow in Fig. 1), and a second-row heat exchange unit 31 located on the leeward
side in the air flow direction. The first-row heat exchange unit 21 includes a plurality
of first-row heat transfer pipes 22, and a plurality of first-row fins 23 joined to
the first-row heat transfer pipes 22, for example, by brazing. The second-row heat
exchange unit 31 includes a plurality of second-row heat transfer pipes 32, and a
plurality of second-row fins 33 joined to the second-row heat transfer pipes 32, for
example, by brazing. Although eight each of the first-row heat transfer pipes 22 and
the second-row heat transfer pipes 32 are illustrated in Fig. 1 and other drawings,
each of the numbers of the first-row heat transfer pipes 22 and the second-row heat
transfer pipes 32 is not specifically limited, and may be any number including one.
The first-row heat transfer pipe 22 corresponds to the first heat transfer pipe in
the present invention. The second-row heat transfer pipe 32 corresponds to the second
heat transfer pipe in the present invention.
[0018] The first-row heat transfer pipes 22 and the second-row heat transfer pipes 32 are
flat pipes, each having a plurality of flow paths aligned in the direction of the
major axis. Each of the first-row heat transfer pipes 22 and the plurality of second-row
heat transfer pipes 32 is bent in a hair-pin shape between one end portion and the
other end portion, to form a corresponding one of turnback sections 22a and 32a. The
first-row heat transfer pipes 22 and the second-row heat transfer pipes 32 are arranged
in a plurality of columns stacked in a direction intersecting the flow of air passing
through the heat exchange unit 2 (blank arrow in Fig. 1). The plurality of first-row
heat transfer pipes 22 and the plurality of second-row heat transfer pipes 32 are
preferably deviated from each other in a height direction when the heat exchange unit
2 is viewed in the airflow direction. Such a configuration improves the heat exchange
efficiency. The respective first end portions and second end portions of the plurality
of first-row heat transfer pipes 22 and the plurality of second-row heat transfer
pipes 32 are aligned to oppose the stacking header 3.
[0019] The stacking header 3 includes a first-row divisional unit 51 and a second-row divisional
unit 61 divided in the direction of the stages of the heat exchange unit 2. A non-illustrated
pipe is connected to the first-row divisional unit 51 via a joint pipe 52. To the
second-row divisional unit 61, a plurality of pipes (not shown) are connected via
a plurality of joint pipes 62. The joint pipe 52 and the joint pipe 62 are, for example,
round pipes. The first-row divisional unit 51 and the second-row divisional unit 61
may be formed in a unified body. The first-row divisional unit 51 corresponds to the
first divisional unit in the present invention, and the second-row divisional unit
61 corresponds to the second divisional unit in the present invention.
[0020] The first-row divisional unit 51 has a plurality of first-row outlet flow paths 51a,
a distribution flow path 51b, a plurality of first-row inlet flow paths 51c, and a
plurality of first-row passing flow paths 51d. The first-row outlet flow path 51a
corresponds to the second outlet flow path in the present invention. The first-row
inlet flow path 51c corresponds to the first inlet flow path in the present invention.
The first-row passing flow path 51d corresponds to the first passing flow path in
the present invention.
[0021] One end portion of the first-row heat transfer pipe 22 is connected to the first-row
outlet flow path 51a, and the other end portion of the first-row heat transfer pipe
22 is connected to the first-row inlet flow path 51c. One end portion of the distribution
flow path 51b is connected to the joint pipe 52, and the other end portions of the
distribution flow path 51b are connected to the plurality of first-row outlet flow
paths 51a. One end portion of the first-row passing flow path 51d is connected to
the first-row inlet flow path 51c, and the other end portion of the first-row passing
flow path 51d is connected to the U-pipe 81.
[0022] The second-row divisional unit 61 has a plurality of second-row outlet flow paths
61a, a plurality of second-row passing flow paths 61b, a plurality of second-row inlet
flow paths 61c, and a plurality of junction flow paths 61d. The second-row outlet
flow path 61a corresponds to the first outlet flow path in the present invention.
The second-row passing flow path 61b corresponds to the second passing flow path in
the present invention. The second-row inlet flow path 61c corresponds to the second
inlet flow path in the present invention. The junction flow path 61d corresponds to
the first junction flow path in the present invention.
[0023] One end portion of the second-row heat transfer pipe 32 is connected to the second-row
outlet flow path 61a, and the other end portion of the second-row heat transfer pipe
32 is connected to the second-row inlet flow path 61c. One end portion of the second-row
passing flow path 61b is connected to the U-pipe 81, and the other end portion of
the second-row passing flow path 61b is connected to the second-row outlet flow path
61a. One end portions of the junction flow path 61d are connected to the plurality
of second-row inlet flow paths 61c, and the other end portion of the junction flow
path 61d is connected to the joint pipe 62.
[0024] The U-pipe 81 may have another shape than the U shape. The U-pipe 81 may be connected
to the first-row passing flow path 51d and the second-row passing flow path 61b, either
directly or via an intermediate member. The U-pipe 81 may be formed of a metal, for
example. The U-pipe 81 corresponds to the first pipe in the present invention. The
first-row inlet flow path 51c, the first-row passing flow path 51d, the U-pipe 81,
the second-row passing flow path 61b, and the second-row outlet flow path 61a each
correspond to the part of the first turnback flow path in the present invention.
[0025] When the heat exchanger 1 acts as evaporator, the refrigerant flows into the distribution
flow path 51b through the joint pipe 52 thus to be distributed to the plurality of
first-row outlet flow paths 51a, and flows into the plurality of first-row inlet flow
paths 51c through the plurality of first-row heat transfer pipes 22. The refrigerant
having entered the plurality of first-row inlet flow paths 51c passes through the
plurality of first-row passing flow paths 51d, the plurality of U-pipes 81, and the
plurality of second-row passing flow paths 61b in this order, and flows into the plurality
of second-row outlet flow paths 61a. The refrigerant having entered the plurality
of second-row outlet flow paths 61a flows into the plurality of second-row inlet flow
paths 61c through the plurality of second-row heat transfer pipes 32, and flows out
of the joint pipe 62 after being merged in the junction flow path 61d.
[0026] When the heat exchanger 1 acts as condenser, the refrigerant flows into the junction
flow path 61d through the joint pipe 62 thus to be distributed to the plurality of
second-row inlet flow paths 61c, and flows into the plurality of second-row outlet
flow paths 61a through the plurality of second-row heat transfer pipes 32. The refrigerant
having entered the plurality of second-row outlet flow paths 61a passes through the
plurality of second-row passing flow paths 61b, the plurality of U-pipes 81, and the
plurality of first-row passing flow paths 51d in this order and flows into the plurality
of first-row inlet flow paths 51c. The refrigerant having entered the plurality of
first-row inlet flow paths 51c flows into the plurality of first-row outlet flow paths
51a through the plurality of first-row heat transfer pipes 22, and flows out of the
joint pipe 52 after being merged in the distribution flow path 51b.
[0027] Although Fig. 1 and other drawings represent the case where one joint pipe 52 is
provided, in other words, one distribution flow path 51b is provided, a plurality
of sets of the joint pipe 52 and the distribution flow path 51b may be provided. Likewise,
although Fig. 1 and other drawings represent the case where four joint pipes 62 are
provided, in other words, four junction flow paths 61d are provided, a different number
of sets of the joint pipe 62 and the junction flow path 61d may be provided. Providing
four sets of the joint pipe 62 and the junction flow path 61d allows reduction of
the width of the second-row divisional unit 61 in the direction of the rows of the
heat exchange unit 2. Further, although Fig. 1 and other drawings represent the case
where the joint pipe 52, the joint pipes 62, and the U-pipes 81 are connected to the
face of the stacking header 3 opposite to the face on the side of the heat exchange
unit 2, those pipes may be connected to another face of the stacking header 3.
(Configuration of Stacking Header)
[0028] Hereafter, a configuration of the stacking header of the heat exchanger according
to Embodiment 1 will be described.
[0029] Fig. 2 is an exploded perspective view of the first-row divisional unit and associated
components, in the heat exchanger according to Embodiment 1. Fig. 3 is an exploded
perspective view of the second-row divisional unit and associated components, in the
heat exchanger according to Embodiment 1. Arrows in Fig. 2 and Fig. 3 indicate the
flow of the refrigerant realized when the heat exchanger 1 acts as evaporator.
[0030] As shown in Fig. 2, the first-row divisional unit 51 includes a first-row first plate
unit 53 and a first-row second plate unit 54 stacked on the first-row first plate
unit 53. The first-row first plate unit 53 corresponds to a part of the first plate
unit in the present invention. The first-row second plate unit 54 corresponds to a
part of the second plate unit in the present invention.
[0031] The first-row first plate unit 53 includes a plate member 53_1, and the first-row
second plate unit 54 includes a plurality of plate members 54_1 to 54_7. The end portions
of the first-row heat transfer pipes 22 are supported by a first-row retention member
24, and the plate member 53_1 and the plurality of plate members 54_1 to 54_7 are
joined to the first-row retention member 24 via a plurality of plate-shaped clad members
55_1 to 55_8, for example, by brazing. A brazing material is applied to one or both
surfaces of each of the clad members 55_1 to 55_8. The clad members 55_1 to 55_8 serve
as joint layers between the first-row retention member 24 and the plate members 53_1
and 54_1 to 54_7. In addition, the flow paths formed in the clad members 55_1 to 55_8
assure the isolation of the refrigerant in the adjacent flow paths in the plate members
53_1 and 54_1 to 54_7 from each other. The first-row retention member 24, the plate
members 53_1 and 54_1 to 54_7, and the clad members 55_1 to 55_8 may be, for example,
made of aluminum. The first-row retention member 24 and the plate members 53_1 and
54_1 to 54_7 may be directly joined to each other, without the intermediation of the
plurality of clad members 55_1 to 55_8.
[0032] The first-row first plate unit 53 has the plurality of first-row outlet flow paths
51a and the plurality of first-row inlet flow paths 51c, aligned in a row. The plurality
of first-row outlet flow paths 51a and the plurality of first-row inlet flow paths
51c are formed in a shape that fits the outer circumferential shape of the first-row
heat transfer pipe 22. The end portions of the first-row heat transfer pipes 22 stick
out from the first-row retention member 24, and the first-row first plate unit 53
is joined to the first-row retention member 24 so that the end portions of the first-row
heat transfer pipes 22 are inserted into the plurality of first-row outlet flow paths
51a and the plurality of first-row inlet flow paths 51c. Alternatively, the end portions
of the first-row heat transfer pipes 22 may be directly connected to the plurality
of first-row outlet flow paths 51a and the plurality of first-row inlet flow paths
51c, without the intermediation of the first-row retention member 24 supporting the
end portions of the first-row heat transfer pipes 22. The end faces of the first-row
heat transfer pipes 22 may stick out from the first-row first plate unit 53, or the
plurality of first-row outlet flow paths 51a and the plurality of first-row inlet
flow paths 51c may be connected to the first-row heat transfer pipes 22 via intermediate
members, so that the end faces of the first-row heat transfer pipes 22 are located
inside the flow paths formed in the intermediate members.
[0033] The first-row second plate unit 54 has the distribution flow path 51b and the plurality
of first-row passing flow paths 51d. The distribution flow path 51b and the plurality
of first-row passing flow paths 51d are aggregates of flow path segments formed in
the plate members 54_1 to 54_7 and flow path segments formed in the clad members 55_2
to 55_8. One end portion of the distribution flow path 51b is connected to the joint
pipe 52, and the other end portions of the distribution flow path 51b is connected
to the plurality of first-row outlet flow paths 51a. The distribution flow path 51b
is repeatedly branched in two ways in a region distant from the heat exchange unit
2. Such a configuration improves the distribution uniformity of the refrigerant when
the heat exchanger 1 acts as evaporator. The distribution flow path 51b has a linear
shape in a region close to the heat exchange unit 2. One end portion of the first-row
passing flow path 51d is connected to the first-row inlet flow path 51c, and the other
end portion of the first-row passing flow path 51d is connected to the U-pipe 81.
The first-row passing flow path 51d has a linear shape in a region close to the heat
exchange unit 2. Further details of the first-row passing flow path 51d will be subsequently
described.
[0034] The joint pipe 52 and the U-pipe 81 may be located in the first-row first plate unit
53. In other words, a part of the distribution flow path 51b and a part of the first-row
passing flow path 51d may be routed through the first-row first plate unit 53.
[0035] As shown in Fig. 3, the second-row divisional unit 61 includes a second-row first
plate unit 63 and a second-row second plate unit 64 stacked on the second-row first
plate unit 63. The second-row first plate unit 63 corresponds to a part of the first
plate unit in the present invention. The second-row second plate unit 64 corresponds
to a part of the second plate unit in the present invention.
[0036] The second-row first plate unit 63 includes a plate member 63_1, and the second-row
second plate unit 64 includes a plurality of plate members 64_1 to 64_7. The end portions
of the second-row heat transfer pipes 32 are supported by a second-row retention member
34, and the plate member 63_1 and the plurality of plate members 64_1 to 64_7 are
joined to the second-row retention member 34 via a plurality of plate-shaped clad
members 65_1 to 65_8, for example, by brazing. A brazing material is applied to one
or both surfaces of each of the clad members 65_1 to 65_8. The clad members 65_1 to
65_8 serve as joint layers between the second-row retention member 34 and the plate
members 63_1 and 64_1 to 64_7. In addition, the flow paths formed in the clad members
65_1 to 65_8 assure the isolation of the refrigerant in the adjacent flow paths in
the plate members 63_1 and 64_1 to 64_7 from each other. The second-row retention
member 34, the plate members 63_1 and 64_1 to 64_7, and the clad members 65_1 to 65_8
may be, for example, made of aluminum. The second-row retention member 34 and the
plate members 63_1 and 64_1 to 64_7 may be directly joined to each other, without
the intermediation of the plurality of clad members 65_1 to 65_8.
[0037] The second-row first plate unit 63 has the plurality of second-row outlet flow paths
61a and the plurality of second-row inlet flow paths 61c, aligned in a row. The plurality
of second-row outlet flow paths 61a and the plurality of second-row inlet flow paths
61c are formed in a shape that fits the outer circumferential shape of the second-row
heat transfer pipe 32. The end portions of the second-row heat transfer pipes 32 stick
out from the second-row retention member 34, and the second-row first plate unit 63
is joined to the second-row retention member 34 so that the end portions of the second-row
heat transfer pipes 32 are inserted into the plurality of second-row outlet flow paths
61a and the plurality of second-row inlet flow paths 61c. Alternatively, the end portions
of the second-row heat transfer pipes 32 may be directly connected to the plurality
of second-row outlet flow paths 61a and the plurality of second-row inlet flow paths
61c, without the intermediation of the second-row retention member 34 supporting the
end portions of the second-row heat transfer pipes 32. The end faces of the second-row
heat transfer pipes 32 may stick out from the second-row first plate unit 63, or the
plurality of second-row outlet flow paths 61a and the plurality of second-row inlet
flow paths 61c may be connected to the second-row heat transfer pipes 32 via intermediate
members, so that the end faces of the second-row heat transfer pipes 32 are located
inside the flow paths formed in the intermediate members.
[0038] The second-row second plate unit 64 has the plurality of second-row passing flow
paths 61b and the plurality of junction flow paths 61d. The second-row passing flow
paths 61b and the plurality of junction flow paths 61d are aggregates of flow path
segments formed in the plate members 64_1 to 64_7 and flow path segments formed in
the clad members 65_2 to 65_8. One end portion of the second-row passing flow path
61b is connected to the U-pipe 81, and the other end portion of the second-row passing
flow path 61b is connected to the second-row outlet flow path 61a. The second-row
passing flow path 61b has a linear shape in a region close to the heat exchange unit
2. Further details of the second-row passing flow path 61b will be subsequently described.
One end portions of the junction flow path 61d are connected to the plurality of second-row
inlet flow paths 61c, and the other end portion of the junction flow path 61d is connected
to the joint pipe 62. The junction flow path 61d merges two flow paths into one. Such
a configuration improves the distribution uniformity of the refrigerant when the heat
exchanger 1 acts as condenser. The junction flow path 61d has a linear shape in a
region close to the heat exchange unit 2.
[0039] The U-pipe 81 and the joint pipe 62 may be located in the second-row first plate
unit 63. In other words, a part of the second-row passing flow path 61b and a part
of the junction flow path 61d may be routed through the second-row first plate unit
63.
< Configuration of Air-conditioning Apparatus Including Heat Exchanger >
[0040] Hereafter, a configuration of an air-conditioning apparatus that includes the heat
exchanger according to Embodiment 1 will be described.
[0041] Fig. 4 and Fig. 5 are block diagrams showing the configuration of the air-conditioning
apparatus including the heat exchanger according to Embodiment 1. Fig. 4 represents
the case where an air-conditioning apparatus 91 performs a heating operation. Fig.
5 represents the case where the air-conditioning apparatus 91 performs a cooling operation.
[0042] As shown in Fig. 4 and Fig. 5, the air-conditioning apparatus 91 includes a compressor
92, a four-way valve 93, an outdoor heat exchanger (heat source-side heat exchanger)
94, an expansion device 95, an indoor heat exchanger (load-side heat exchanger) 96,
an outdoor fan (heat source-side fan) 97, an indoor fan (load-side fan) 98, and a
controller 99. The compressor 92, the four-way valve 93, the outdoor heat exchanger
94, the expansion device 95, and the indoor heat exchanger 96 are connected via a
refrigerant pipe, to form a refrigerant circuit. The four-way valve 93 may be another
type of flow switching device.
[0043] The outdoor heat exchanger 94 corresponds to the heat exchanger 1. In the outdoor
heat exchanger 94, the first-row divisional unit 51 is located on the windward side
and the second-row divisional unit 61 is located on the leeward side, in the airflow
generated when the outdoor fan 97 is driven. The outdoor fan 97 may be provided either
on the windward or leeward side of the heat exchanger 1.
[0044] To the controller 99, for example, the compressor 92, the four-way valve 93, the
expansion device 95, the outdoor fan 97, the indoor fan 98, and various sensors are
connected. The controller 99 switches the flow paths in the four-way valve 93, thereby
switching between the heating operation and the cooling operation.
[0045] With reference to Fig. 4, the flow of the refrigerant in the heating operation will
be described hereafter.
[0046] The high-pressure and high-temperature gas refrigerant discharged from the compressor
92 flows into the indoor heat exchanger 96 through the four-way valve 93, and is condensed
through heat exchange with air supplied by the indoor fan 98, thereby heating the
indoor air. The condensed refrigerant turns into high-pressure subcooled liquid refrigerant
and flows out of the indoor heat exchanger 96, and then turns into low-pressure two-phase
gas-liquid refrigerant in the expansion device 95. The low-pressure two-phase gas-liquid
refrigerant flows into the outdoor heat exchanger 94, and is evaporated through heat
exchange with air supplied by the outdoor fan 97. The evaporated refrigerant turns
into low-pressure superheated gas refrigerant and flows out of the outdoor heat exchanger
94, and is then sucked into the compressor 92 through the four-way valve 93. Thus,
the outdoor heat exchanger 94 acts as evaporator in the heating operation.
[0047] In the outdoor heat exchanger 94, the refrigerant flows into the distribution flow
path 51b of the first-row divisional unit 51 thus to be branched, and flows into the
first-row heat transfer pipes 22 of the first-row heat exchange unit 21. The refrigerant
having entered the first-row heat transfer pipes 22 sequentially passes through the
first-row passing flow paths 51d, the U-pipes 81, and the second-row passing flow
paths 61b, and flows into the second-row heat transfer pipes 32 of the second-row
heat exchange unit 31. The refrigerant having entered the second-row heat transfer
pipes 32 flows into the junction flow paths 61d of the second-row divisional unit
61, thus to be merged.
[0048] With reference to Fig. 5, the flow of the refrigerant in the cooling operation will
be described hereafter.
[0049] The high-pressure and high-temperature gas refrigerant discharged from the compressor
92 flows into the outdoor heat exchanger 94 through the four-way valve 93, and is
condensed through heat exchange with air supplied by the outdoor fan 97. The condensed
refrigerant turns into high-pressure subcooled liquid refrigerant, and flows out of
the outdoor heat exchanger 94 and then turns into low-pressure two-phase gas-liquid
refrigerant in the expansion device 95. The low-pressure two-phase gas-liquid refrigerant
flows into the indoor heat exchanger 96, and is evaporated through heat exchange with
air supplied by the indoor fan 98, thereby cooling the indoor air. The evaporated
refrigerant turns into low-pressure superheated gas refrigerant and flows out of the
indoor heat exchanger 96, and is then sucked into the compressor 92 through the four-way
valve 93. Thus, the outdoor heat exchanger 94 acts as condenser in the cooling operation.
[0050] In the outdoor heat exchanger 94, the refrigerant flows into the junction flow paths
61d of the second-row divisional unit 61 thus to be branched, and flows into the second-row
heat transfer pipes 32 of the second-row heat exchange unit 31. The refrigerant having
entered the second-row heat transfer pipes 32 sequentially passes through the second-row
passing flow paths 61b, the U-pipes 81, and the first-row passing flow paths 51d,
and flows into the first-row heat transfer pipes 22 of the first-row heat exchange
unit 21. The refrigerant having entered the first-row heat transfer pipes 22 flows
into the distribution flow path 51b of the first-row divisional unit 51, thus to be
merged.
[0051] In the outdoor heat exchanger 94, the first-row heat exchange unit 21 and the second-row
heat exchange unit 31 are aligned side by side in the flow direction of air passing
through the heat exchange unit 2 (blank arrow in Fig. 5). The heat exchange amount
may be increased, for example, by increase the front-view area of the outdoor heat
exchanger 94; however, in this case, the size of the casing incorporating the outdoor
heat exchanger 94 is increased. In addition, although the heat exchange amount may
be increased by increasing the number of fins, it is difficult to locate the fins
in a pitch narrower than 1 mm from the viewpoint of drain efficiency, defrosting performance,
and dust resistance, and thus a sufficient increase in heat exchange amount may not
be attained. In contrast, increasing the number of rows of the heat transfer pipes
as in the case of the outdoor heat exchanger 94 enables the heat exchange amount to
be increased without changing the front-view area of the outdoor heat exchanger 94
or the pitch of the fins. Providing two rows leads to an increase heat exchange amount
of approximately 50% or more. Further, the front-view area of the outdoor heat exchanger
94, the pitch of the fins, or other factors may additionally be modified.
[0052] In addition, the header (stacking header 3) is provided only on one side of the outdoor
heat exchanger 94. In the case where the outdoor heat exchanger 94 is bent and disposed
along a plurality of faces of the casing incorporating the outdoor heat exchanger
94, to increase the effective volume of the heat exchange unit 2, the end portions
of the heat transfer pipe rows are deviated from each other because of differences
in curvature radius of the bent portion of each of the rows. Providing the header
(stacking header 3) only on one side as in the case of the outdoor heat exchanger
94 allows the degree of designing freedom and production efficiency to be improved,
because it suffices that only the end portions of the rows on one side are aligned
even when the end portions on the other side are deviated. In this case, further,
the heat exchange unit 2 may be bent after the components of the outdoor heat exchanger
94 are attached, leading to further improvement in production efficiency.
[0053] Further, the first-row heat transfer pipes 22 are located on the windward side with
respect to the second-row heat transfer pipes 32, when the outdoor heat exchanger
94 acts as condenser. In the case where the headers are provided on the respective
sides of the outdoor heat exchanger 94, it is difficult to improve the condensing
performance by giving a difference in refrigerant temperature in each of the rows.
When the first-row heat transfer pipes 22 and the second-row heat transfer pipes 32
are flat pipes, in particular, sufficient degree of freedom in bending work is unable
to be secured unlike a circular pipe, and thus it is difficult to give the difference
in refrigerant temperature in each of the rows by deforming the flow paths of the
refrigerant. However, in the case where the first-row heat transfer pipes 22 and the
second-row heat transfer pipes 32 are connected to the stacking header 3 as in the
case of the outdoor heat exchanger 94, the refrigerant temperature naturally becomes
different in each of the rows, and thus the flow direction of the refrigerant and
the flow direction of air passing through the heat exchange unit 2 can be easily made
to oppose without deforming the refrigerant flow path.
< Details of First Passing Flow Path and Second Passing Flow Path >
[0054] Hereafter, the details of the first passing flow path and the second passing flow
path of the heat exchanger according to Embodiment 1 will be described.
[0055] Fig. 6 is a schematic cross-sectional view for explaining the details of the first
passing flow path and the second passing flow path of the heat exchanger according
to Embodiment 1.
[0056] As shown in Fig. 6, the first-row passing flow path 51d is straight in a section
corresponding to a flow path length L1 from the end face of the first-row heat transfer
pipe 22. The second-row passing flow path 61b is straight in a section corresponding
to a flow path length L2 from the end face of the second-row heat transfer pipe 32.
The section of the flow path length L1 serves as runway for the refrigerant having
passed through the U-pipe 81 to flow into the first-row heat transfer pipe 22. The
section of the flow path length L2 serves as runway for the refrigerant having passed
through the U-pipe 81 to flow into the second-row heat transfer pipe 32. Providing
thus the runways allow uniformization of the amount of refrigerant flowing into the
inlet port of each of the plurality of flow paths formed in the first-row heat transfer
pipe 22 and the second-row heat transfer pipe 32.
[0057] Fig. 7 is a graph showing a relationship between the flow path length L2 and the
uniformity of the refrigerant, realized when the heat exchanger according to Embodiment
1 acts as evaporator. Fig. 7 shows the relationship between inlet port numbers and
the distribution ratio, in other words, a ratio of the refrigerant amount to the total
amount of the refrigerant flowing into the inlet ports, under different settings of
the flow path length L2. Here, the inlet port number 1 represents the inlet port in
the end face of the second-row heat transfer pipe 32 farthest from the first-row heat
transfer pipe 22.
[0058] As shown in Fig. 7, when the heat exchanger 1 acts as evaporator, in other words,
when the refrigerant having passed through the U-pipe 81 flows into the second-row
heat transfer pipe 32 through the second-row passing flow path 61b, the distribution
ratio tends to be higher in the inlet ports more distant from the first-row heat transfer
pipe 22. When ten inlet ports are provided, the heat exchange performance of the heat
exchange unit 2 can be secured by setting the distribution ratio of the inlet ports
in a range of 0.10 ± 0.03. Thus, when the hydraulic equivalent diameter of the flow
path in the range of the flow path length L2 is denoted by De, the heat exchange performance
of the heat exchange unit 2 can be secured by setting as flow path length L2 ≥ 4De.
[0059] Fig. 8 is a graph showing a relationship between the flow path length L1 and the
uniformity of the refrigerant, realized when the heat exchanger according to Embodiment
1 acts as condenser. Fig. 8 shows the relationship between inlet port numbers and
the distribution ratio, in other words, a ratio of the refrigerant amount to the total
amount of the refrigerant flowing into the inlet ports, under different settings of
the flow path length L1. Here, the inlet port number 1 represents the inlet port in
the end face of the first-row heat transfer pipe 22 farthest from the second-row heat
transfer pipe 32.
[0060] As shown in Fig. 8, when the heat exchanger 1 acts as condenser, in other words,
when the refrigerant having passed through the U-pipe 81 flows into the first-row
heat transfer pipe 22 through the first-row passing flow path 51d, the distribution
ratio tends to be higher in the inlet ports more distant from the second-row heat
transfer pipe 32. When ten inlet ports are provided, the heat exchange performance
of the heat exchange unit 2 can be secured by setting the distribution ratio of the
inlet ports in a range of 0.10 ± 0.03. Thus, when the hydraulic equivalent diameter
of the flow path in the range of the flow path length L1 is denoted by De, the heat
exchange performance of the heat exchange unit 2 can be secured by setting as flow
path length L1 ≥ 2De.
[0061] To be more detailed, when the heat exchanger 1 acts as evaporator, the two-phase
gas-liquid refrigerant, in other words, a mixture of liquid phase refrigerant and
gas phase refrigerant, which is relatively difficult to be uniformly distributed,
passes through the U-pipe 81, and thus the flow path length L2 serving as runway has
to be made longer. In contrast, when the heat exchanger 1 acts as condenser, the gas-phase
refrigerant, which is relatively easy to be uniformly distributed, passes through
the U-pipe 81, and thus the flow path length L1 serving as runway can be made shorter
compared with the flow path length L2. Thus, adjusting the number or thickness of
the plate members 54_1 to 54_7 and 64_1 to 64_7, which defines the ranges corresponding
to the flow path length L1 and the flow path length L2 in the first-row second plate
unit 54 and the second-row second plate unit 64, to make each of the flow path length
L1 and the flow path length L2 equal to or larger than 4De allows the heat exchange
performance of the heat exchange unit 2 to be secured, both when the heat exchanger
1 acts as evaporator and when the heat exchanger 1 acts as condenser.
[0062] In addition, adjusting the number or thickness of the plate members 54_1 to 54_7,
which defines the range corresponding to the flow path length L1 in the first-row
second plate unit 54, to make the flow path length L1 equal to or larger than 2De
and shorter than the flow path length L2 also allows the heat exchange performance
of the heat exchange unit 2 to be secured, both when the heat exchanger 1 acts as
evaporator and when the heat exchanger 1 acts as condenser. Such a configuration contributes
to reducing the weight and the cost of the heat exchanger 1.
< Effects of Heat Exchanger >
[0063] Hereafter, the effects of the heat exchanger according to Embodiment 1 will be described.
[0064] In the stacking header 3, the first-row inlet flow path 51c, the first-row passing
flow path 51d, the U-pipe 81, the second-row passing flow path 61b, and the second-row
outlet flow path 61a constitute the turnback flow path. Thus, for example, when the
stacking header 3 is employed for an apparatus such as the heat exchanger 1 having
a plurality of rows of heat exchange units (first-row heat exchange unit 21 and second-row
heat exchange unit 31) aligned in the airflow direction, there is no need to employ
pipes or other components to branch the refrigerant flowing out of the outlet flow
path into a plurality of rows in a part of the apparatus other than the stacking header
3, and the complication of the structure of the apparatus for which the stacking header
3 is employed can be eased.
[0065] In addition, the turnback flow path is composed of the first-row passing flow path
51d and the second-row passing flow path 61b, which are the aggregates of the flow
path segments formed in the plate members 54_1 to 54_7 and 64_1 to 64_7, and the flow
path segments formed in the plate-shaped clad members 55_2 to 55_8 and 65_2 to 65_8,
and the U-pipe 81. Thus, the distance between the turnback section and the joint of
the first-row passing flow path 51d and the U-pipe 81 or the joint of the second-row
passing flow path 61b and the U-pipe 81 can be extended to level off the unevenness
of the refrigerant amount among the flow paths produced at the turnback section of
the turnback flow path (U-shaped section of the U-pipe 81), without increasing the
number of stacks in the stacking header 3 or the thickness of the plate members, in
other words, by extending the length of the end portions of the U-pipe 81. Thus, uniform
refrigerant distribution and reduction in cost and weight can both be achieved. Further,
since the turnback section of the turnback flow path is the U-pipe 81, in other words,
a pipe structure, the degree of designing freedom of the turnback section, as well
as versatility of the stacking header 3 can be improved.
[0066] The stacking header 3 is divided into the first-row divisional unit 51 and the second-row
divisional unit 61, between the first plate unit having the first-row outlet flow
path 51a, the distribution flow path 51b, the first-row inlet flow path 51c, and the
first-row passing flow path 51d, and the second plate unit having the second-row outlet
flow path 61a, the second-row passing flow path 61b, the second-row inlet flow path
61c, and the junction flow path 61d. Such a configuration reduces heat exchange between
the refrigerant about to flow into the heat exchange unit 2 and the refrigerant having
passed through the heat exchange unit 2, thereby improving the heat exchange efficiency
of the heat exchanger 1. The boundary between the first-row divisional unit 51 and
the second-row divisional unit 61 may be either straight or curved. A heat insulation
material may be provided between the first-row divisional unit 51 and the second-row
divisional unit 61. The division is preferably performed by pressing or a similar
method. In this case, the division can be performed at the same time when the flow
paths in the plate members 53_1, 54_1 to 54_7, 63_1, and 64_1 to 64_7 and in the clad
members 55_1 to 55_8 and 65_1 to 65_8 are processed, leading to reduction in manufacturing
cost. Further, the division of the divisional units is assured, further assuring the
reduction of the heat exchange between the refrigerant about to flow into the heat
exchange unit 2 and the refrigerant having passed through the heat exchange unit 2.
[0067] Further, when the heat exchanger 1 acts as evaporator, the gas-phase refrigerant
flows into the second-row inlet flow path 61c, and hence the flow path cross-sectional
area of the junction flow path 61d has to be made as large as possible, to reduce
the pressure loss suffered by the gas refrigerant. Since the heat exchange between
the refrigerant about to flow into the heat exchange unit 2 and the refrigerant having
passed through the heat exchange unit 2 is reduced because the stacking header 3 is
divided into the first-row divisional unit 51 and the second-row divisional unit 61,
the junction flow path 61d can be extended to a region close to the first-row divisional
unit 51 to significantly reduce the pressure loss of the gas refrigerant, and consequently
the performance level of the stacking header 3, as well as the operation efficiency
of the air-conditioning apparatus 91 can be improved.
Embodiment 2
[0068] Hereafter, a heat exchanger according to Embodiment 2 will be described.
[0069] The description same as or similar to those of Embodiment 1 will be simplified or
omitted, as the case may be.
< Configuration of Heat Exchanger >
[0070] Hereafter, a configuration of the heat exchanger according to Embodiment 2 will be
described.
(General Configuration of Heat Exchanger)
[0071] Hereafter, a general configuration of the heat exchanger according to Embodiment
2 will be described.
[0072] Fig. 9 is a perspective view of the heat exchanger according to Embodiment 2.
[0073] As shown in Fig. 9, the heat exchange unit 2 includes the first-row heat exchange
unit 21 located on the windward side in the flow direction of air passing through
the heat exchange unit 2 (blank arrow in Fig. 1), the second-row heat exchange unit
31 located on the leeward side of the first-row heat exchange unit 21, and a third-row
heat exchange unit 41 located on the leeward side of the second-row heat exchange
unit 31. The third-row heat exchange unit 41 includes a plurality of third-row heat
transfer pipes 42, and a plurality of third-row fins 43 joined to the third-row heat
transfer pipes 42, for example, by brazing.
[0074] The third-row heat transfer pipe 42 is a flat pipe having a plurality of flow paths
aligned in the direction of the major axis. Each of the third-row heat transfer pipes
42 is bent in a hair-pin shape between one end portion and the other end portion,
to form a turnback section 42a. The third-row heat transfer pipes 42 are arranged
in a plurality of columns stacked in a direction intersecting the flow of air passing
through the heat exchange unit 2 (blank arrow in Fig. 1). The respective first end
portions and second end portions of the plurality of third-row heat transfer pipes
42 are aligned to oppose the stacking header 3.
[0075] The stacking header 3 includes the first-row divisional unit 51, the second-row divisional
unit 61, and a third-row divisional unit 71, divided in the direction of the stages
of the heat exchange unit 2. To the third-row divisional unit 71, a plurality of pipes
(not shown) are connected via a plurality of joint pipes 72. Two or more of the first-row
divisional unit 51, the second-row divisional unit 61, and the third-row divisional
unit 71 may be formed in a unified body. The first-row divisional unit 51 corresponds
to the first divisional unit in the present invention, and the second-row divisional
unit 61 and the third-row divisional unit 71 each correspond to the second divisional
unit in the present invention.
[0076] The third-row divisional unit 71 has a plurality of third-row outlet flow paths 71a,
plurality of third-row passing flow paths 71b, a plurality of third-row inlet flow
paths 71c, and a plurality of junction flow paths 71d. The third-row outlet flow path
71a corresponds to the third outlet flow path in the present invention. The third-row
passing flow path 71b corresponds to the third passing flow path in the present invention.
The third-row inlet flow path 71c corresponds to the third inlet flow path in the
present invention. The junction flow path 71d corresponds to the second junction flow
path in the present invention.
[0077] One end portion of the third-row heat transfer pipe 42 is connected to the third-row
outlet flow path 71a, and the other end portion of the third-row heat transfer pipe
42 is connected to the third-row inlet flow path 71c. One end portion of the third-row
passing flow path 71b is connected to a branch pipe 82, and the other end portion
of the third-row passing flow path 71b is connected to the third-row outlet flow path
71a. One end portions of the junction flow path 71d are connected to the plurality
of third-row inlet flow paths 71c, and the other end portion of the junction flow
path 71d is connected to the joint pipe 72.
[0078] The branch pipe 82, instead of the U-pipe 81, is connected to the end portion of
the junction flow path 61d of the second-row divisional unit 61 not communicating
with the second-row inlet flow path 61c. In other words, the branch pipe 82 includes
a branch portion to allow communication between the junction flow path 61d of the
second-row divisional unit 61 and two third-row passing flow paths 71b of the third-row
divisional unit 71. Preferably, the branch pipe 82 may be formed by bulge forming.
The branch pipe 82 may be connected to the junction flow path 61d and the third-row
passing flow paths 71b either directly or via an intermediate member. The branch pipe
82 is, for example, made of a metal. The plurality of second-row inlet flow paths
61c, the junction flow path 61d, the branch pipe 82, the plurality of third-row passing
flow paths 71b, and the plurality of third-row outlet flow paths 71a each correspond
to a part of the second turnback flow path in the present invention.
[0079] When the heat exchanger 1 acts as evaporator, the refrigerant is merged in the junction
flow path 61d and flows into the plurality of third-row outlet flow paths 71a after
passing through the plurality of branch pipes 82 and the plurality of third-row passing
flow paths 71b in this order. The refrigerant having entered the plurality of third-row
outlet flow paths 71a flows into the plurality of third-row inlet flow paths 71c through
the plurality of third-row heat transfer pipes 42, and flows out of the joint pipe
72 after being merged in the junction flow path 71d.
[0080] When the heat exchanger 1 acts as condenser, the refrigerant flows into the junction
flow path 71d through the joint pipe 72 thus to be distributed to the plurality of
third-row inlet flow paths 71c, and flows into the plurality of third-row outlet flow
paths 71a through the plurality of third-row heat transfer pipes 42. The refrigerant
having entered the plurality of third-row outlet flow paths 71a passes through the
plurality of third-row passing flow paths 71b and the plurality of branch pipes 82
in this order and flows into the junction flow path 61d.
[0081] Although Fig. 9 and Fig. 10 represent the case where four branch pipes 82 are provided,
in other words, where the junction flow path 61d merges two flow paths into one, the
number of branch pipes 82 may be other than four, provided that the number agrees
with the number of flow paths merged by the junction flow path 61d. Further, although
Fig. 9 and Fig. 10 represent the case where the branch pipes 82 are connected to the
face of the stacking header 3 opposite to the face on the side of the heat exchange
unit 2, branch pipes 82 may be connected to another face of the stacking header 3.
(Configuration of Stacking Header)
[0082] Hereafter, a configuration of the stacking header of the heat exchanger according
to Embodiment 2 will be described.
[0083] Fig. 10 is an exploded perspective view of the third-row divisional unit and associated
components, in the heat exchanger according to Embodiment 2. Arrows in Fig. 10 indicate
the flow of the refrigerant realized when the heat exchanger 1 acts as evaporator.
[0084] As shown in Fig. 10, the third-row divisional unit 71 includes a third-row first
plate unit 73 and a third-row second plate unit 74 stacked on the third-row first
plate unit 73. The third-row first plate unit 73 and the third-row second plate unit
74 are configured in the same way as the second-row first plate unit 63 and the second-row
second plate unit 64. The third-row first plate unit 73 corresponds to a part of the
first plate unit in the present invention. The third-row second plate unit 74 corresponds
to a part of the second plate unit in the present invention.
[0085] Here, the branch pipe 82 may be provided in the third-row first plate unit 73. In
other words, a part of the third-row passing flow path 71b and a part of the junction
flow path 71d may be routed through the third-row first plate unit 73.
< Effects of Heat Exchanger >
[0086] Hereafter, the effects of the heat exchanger according to Embodiment 2 will be described.
[0087] In the stacking header 3, the plurality of second-row inlet flow paths 61c, the junction
flow path 61d, the branch pipe 82, the plurality of third-row passing flow paths 71b,
and the plurality of third-row outlet flow paths 71a constitute the turnback flow
path. Thus, for example, when the stacking header 3 is employed for an apparatus such
as the heat exchanger 1 having three rows of heat exchange units (first-row heat exchange
unit 21, second-row heat exchange unit 31, and third-row heat exchange unit 41) aligned
in the airflow direction, there is no need to employ pipes or other components to
branch the refrigerant flowing out of the outlet flow path into three rows in a part
of the apparatus other than the stacking header 3, and the complication of the structure
of the apparatus for which the stacking header 3 is employed can be eased. Here, the
stacking header 3 may include four or more divisional units, without limitation to
three.
[0088] In the stacking header 3, the third-row divisional unit 71 has the same configuration
as that of the second-row divisional unit 61. Thus, when the third-row divisional
unit 71 and the second-row divisional unit 61 are divided from each other, the common
components can be employed to cope with the increase in number of rows of the heat
exchange unit 2, and when the third-row divisional unit 71 and the second-row divisional
unit 61 are formed in a unified body, the common processing steps and common jigs
(for example, press die) can be employed to cope with the increase in number of rows
of the heat exchange unit 2. Consequently, the cost of the heat exchanger 1 can be
reduced.
Embodiment 3
[0089] Hereafter, a heat exchanger according to Embodiment 3 will be described.
[0090] The description same as or similar to those of Embodiment 1 and Embodiment 2 will
be simplified or omitted, as the case may be.
< Configuration of Heat Exchanger >
[0091] Hereafter, a configuration of the heat exchanger according to Embodiment 3 will be
described.
(General Configuration of Heat Exchanger)
[0092] Hereafter, a general configuration of the heat exchanger according to Embodiment
3 will be described.
[0093] Fig. 11 is a perspective view of the heat exchanger according to Embodiment 3.
[0094] As shown in Fig. 11, the stacking header 3 includes the first-row divisional unit
51, the second-row divisional unit 61A, and a third-row divisional unit 71, divided
in the direction of the stages of the heat exchange unit 2. The second-row divisional
unit 61A has a different configuration from the second-row divisional unit 61 according
to Embodiment 2. The first-row divisional unit 51 corresponds to the first divisional
unit in the present invention, and the combination of the second-row divisional unit
61A and the third-row divisional unit 71 corresponds to the second divisional unit
in the present invention.
[0095] The second-row divisional unit 61A has plurality of second-row outlet flow paths
61Aa, a plurality of second-row first passing flow paths 61Ab, a plurality of second-row
inlet flow paths 61Ac, and a plurality of second-row second passing flow paths 61Ad.
The second-row outlet flow path 61Aa corresponds to the first outlet flow path in
the present invention. The second-row first passing flow path 61Ab corresponds to
the second passing flow path in the present invention. The second-row inlet flow path
61Ac corresponds to the fourth inlet flow path in the present invention. The second-row
second passing flow path 61Ad corresponds to the fourth passing flow path in the present
invention. The third-row outlet flow path 71a corresponds to the fourth outlet flow
path in the present invention. The third-row passing flow path 71b corresponds to
the fifth passing flow path in the present invention. The third-row inlet flow path
71c corresponds to the second inlet flow path in the present invention. The junction
flow path 71d corresponds to the first junction flow path in the present invention.
[0096] The U-pipe 81, instead of the branch pipe 82, is connected to the end portion of
the second-row second passing flow path 61Ad of the second-row divisional unit 61A
not communicating with the second-row inlet flow path 61Ac. The U-pipe 81 in this
case corresponds to the second pipe in the present invention. The second-row inlet
flow path 61Ac, the second-row second passing flow path 61Ad, the U-pipe 81, the third-row
passing flow path 71b, and the third-row outlet flow path 71a each correspond to a
part of the third turnback flow path in the present invention.
(Configuration of Stacking Header)
[0097] Hereafter, a configuration of the stacking header of the heat exchanger according
to Embodiment 3 will be described.
[0098] Fig. 12 is an exploded perspective view of the second-row divisional unit and associated
components, in the heat exchanger according to Embodiment 3. Arrows in Fig. 12 indicate
the flow of the refrigerant realized when the heat exchanger 1 acts as evaporator.
[0099] As shown in Fig. 12, the second-row divisional unit 61A includes a second-row first
plate unit 63A and a second-row second plate unit 64A stacked on the second-row first
plate unit 63A. The second-row first plate unit 63A corresponds to a part of the first
plate unit in the present invention. The second-row second plate unit 64A corresponds
to a part of the second plate unit in the present invention.
[0100] The second-row first plate unit 63A has the plurality of second-row outlet flow paths
61Aa and the plurality of second-row inlet flow paths 61Ac, aligned in a row. The
second-row second plate unit 64A has the plurality of second-row first passing flow
paths 61Ab and the plurality of second-row second passing flow paths 61Ad. One end
portion of the second-row first passing flow path 61Ab is connected to the U-pipe
81, and the other end portion of the second-row first passing flow path 61Ab is connected
to the second-row outlet flow path 61Aa. The second-row first passing flow path 61Ab
has a linear shape in a region close to the heat exchange unit 2. One end portion
of the second-row second passing flow path 61Ad is connected to the second-row inlet
flow path 61Ac, and the other end portion of the second-row second passing flow path
61Ad is connected to the U-pipe 81. The second-row second passing flow path 61Ad has
a linear shape in a region close to the heat exchange unit 2.
[0101] The U-pipe 81 may be provided in the second-row first plate unit 63A. In other words,
a part of the second-row first passing flow path 61Ab and a part of the second-row
second passing flow path 61Ad may be routed through the second-row first plate unit
63A.
< Effects of Heat Exchanger >
[0102] Hereafter, the effects of the heat exchanger according to Embodiment 3 will be described.
[0103] In the stacking header 3, the second-row inlet flow path 61Ac, the second-row second
passing flow path 61Ad, the U-pipe 81, the third-row passing flow path 71b, and the
third-row outlet flow path 71a constitute the turnback flow path. Thus, for example,
when the stacking header 3 is employed for an apparatus such as the heat exchanger
1 having three rows of heat exchange units (first-row heat exchange unit 21, second-row
heat exchange unit 31, and third-row heat exchange unit 41) aligned in the airflow
direction, there is no need to employ pipes or other components to branch the refrigerant
flowing out of the outlet flow path into three rows in a part of the apparatus other
than the stacking header 3, and the complication of the structure of the apparatus
for which the stacking header 3 is employed can be eased. Here, the stacking header
3 may include four or more divisional units, without limitation to three.
[0104] Although Embodiment 1 to Embodiment 3 have been described above, the present invention
is not limited to those Embodiments. For example, a part or the whole of each of the
Embodiments may be combined as desired. Reference Signs List
[0105] 1: heat exchanger, 2: heat exchange unit, 3: stacking header, 21: first-row heat
exchange unit, 22: first-row heat transfer pipe, 22a: turnback section, 23: first-row
fin, 24: first-row retention member, 31: second-row heat exchange unit, 32: second-row
heat transfer pipe, 32a: turnback section, 33: second-row fin, 34: second-row retention
member, 41: third-row heat exchange unit, 42: third-row heat transfer pipe, 42a: turnback
section, 43: third-row fin, 44: third-row retention member, 51: first-row divisional
unit, 51a: first-row outlet flow path, 51b: distribution flow path, 51c: first-row
inlet flow path, 51d: first-row passing flow path, 52: joint pipe, 53: first-row first
plate unit, 53_1: plate member, 54: first-row second plate unit, 54_1 to 54_7: plate
member, 55_1 to 55_8: clad member, 61, 61A: second-row divisional unit, 61a, 61Aa:
second-row outlet flow path, 61b: second-row passing flow path, 61Ab: second-row first
passing flow path, 61c, 61Ac: second-row inlet flow path, 61d: junction flow path,
61Ad: second-row second passing flow path, 62: joint pipe, 63, 63A: second-row first
plate unit, 63_1: plate member, 64, 64A: second-row second plate unit, 64_1 to 64_7:
plate member, 65_1 to 65_8: clad member, 71: third-row divisional unit, 71a: third-row
outlet flow path, 71b: third-row passing flow path, 71c: third-row inlet flow path,
71d: junction flow path, 72: joint pipe, 73: third-row first plate unit, 73_1: plate
member, 74: third-row second plate unit, 74_1 to 74_7: plate member, 75_1 to 75_8:
clad member, 81: U-pipe, 82: branch pipe, 91: air-conditioning apparatus, 92: compressor,
93: four-way valve, 94: outdoor heat exchanger, 95: expansion device, 96: indoor heat
exchanger, 97: outdoor fan, 98: indoor fan, 99: controller
1. Stapelkopfteil, umfassend:
eine erste Platteneinheit (53), die einen ersten Einlassströmungspfad (51c), einen
ersten Auslassströmungspfad (61a), eine Vielzahl an zweiten Auslassströmungspfaden
(51a) und eine Vielzahl an zweiten Einlassströmungspfaden (61c) aufweist,
eine zweite Platteneinheit (54), die mit der ersten Platteneinheit (53) verbunden
ist und zumindest einen Teil eines ersten Durchströmungspfades (51d) für Kühlmittel,
das vom ersten Einlassströmungspfad (51c) zum Hindurchtreten von einem stromauf liegenden
Endabschnitt zu einem stromab liegenden Endabschnitt davon strömt, und zumindest einen
Teil eines zweiten Durchströmungspfades (61b) für Kühlmittel aufweist, das von einem
stromauf liegenden Endabschnitt zu einem stromab liegenden Endabschnitt davon zum
ersten Auslassströmungspfad (61a) hindurchtritt, wobei die zweite Platteneinheit (54)
auch zumindest einen Teil eines Verteilungsströmungspfades (51b) umfasst, um das Kühlmittel
an die Vielzahl an zweiten Auslassströmungspfaden (51a) zu verteilen; und
ein erstes Rohr (81), das den stromab liegenden Endabschnitt des ersten Durchströmungspfades
(51d) und den stromauf liegenden Endabschnitt des zweiten Durchströmungspfades (61b)
verbindet, um einen ersten Rücklaufströmungspfad (51c, 51d, 81, 61b, 61a) zu bilden;
dadurch gekennzeichnet, dass
die zweite Platteneinheit zumindest einen Teil eines ersten Verbindungsströmungspfades
(61d) aufweist, der einen stromauf liegenden Endabschnitt und einen stromab liegenden
Endabschnitt zum Zusammenmischen von Kühlmittel, das durch die Vielzahl zweiter Einlassströmungspfade
(61c) hineinströmt, aufweist.
2. Stapelkopfteil nach Anspruch 1,
wobei ein Bereich eines Strömungspfades, durch den Kühlmittel, das durch das erste
Rohr (81) hindurchtritt, hindurchtritt und eine Strömungspfadlänge L zu einer stromauf
liegenden Seite einer Endfläche eines Wärmeleitrohrs aufweist, das mit einem der ersten
Einlassströmungspfade (51c) und dem ersten Auslassströmungspfad (61a), der an einer
stromab liegenden Seite liegt, verbunden ist, gerade ist, und
die Strömungspfadlänge L viermal oder noch länger ist als ein hydraulisch äquivalenter
Durchmesser De des Bereichs.
3. Stapelkopfteil nach Anspruch 1,
wobei die erste Platteneinheit (53) und die zweite Platteneinheit (54) in eine erste
Teileinheit (51), die den Verteilungsströmungspfad (51b), die Vielzahl an zweiten
Auslassströmungspfaden (51a), den ersten Einlassströmungspfad (51c) und den ersten
Durchströmungspfad (51d) aufweist, und
eine zweite Teileinheit (61), die den zweiten Durchströmungspfad (61b), den ersten
Auslassströmungspfad (61a), die Vielzahl an zweiten Einlassströmungspfaden (61c) und
den ersten Verbindungsströmungspfad (61d) aufweist, geteilt sind.
4. Stapelkopfteil nach Anspruch 3,
wobei der stromaufwärtige Endabschnitt des ersten Durchströmungspfades (51d), der
mit dem ersten Einlassströmungspfad (51c) kommuniziert, und der stromabwärtige Endabschnitt
des zweiten Durchströmungspfades (61b), der mit dem ersten Auslassströmungspfad (61a)
kommuniziert, jeweils ein gerader Bereich sind, und
der gerade Bereich des ersten Durchströmungspfades (51d) kürzer ist als der gerade
Bereich des zweiten Durchströmungspfades (61b).
5. Stapelkopfteil nach einem der Ansprüche 1 bis 4,
wobei die erste Platteneinheit (53) eine Vielzahl dritter Auslassströmungspfade (71a)
und eine Vielzahl dritter Einlassströmungspfade (71c) aufweist,
die zweite Platteneinheit (54) zumindest einen Teil jedes einer Vielzahl an dritten
Durchströmungsflüssen (71b), die jeweils einen stromauf liegenden Endabschnitt und
einen stromab liegenden Endabschnitt zur Kommunikation von Kühlmittel aufweisen, das
durch einen der Vielzahl an dritten Auslassströmungspfaden (71a) hindurchtritt, und
zumindest einen Teil eines zweiten Verbindungsströmungspfads (71d) zum Zusammenmischen
von Kühlmittel, das durch die Vielzahl dritter Einlassströmungspfade (71c) hineinströmt,
umfasst, und wobei
ein stromab liegender Endabschnitt des ersten Verbindungsströmungspfads (61d) und
ein stromauf liegender Endabschnitt jedes der Vielzahl an dritten Durchströmungspfaden
(71b) miteinander durch ein Abzweigrohr kommunizieren, um einen zweiten Rückströmungspfad
(61c, 61d, 82, 71b, 71a) zu bilden.
6. Stapelkopfteil nach einem der Ansprüche 1 bis 4,
wobei die erste Platteneinheit (53) einen vierten Einlassströmungspfad (61Ac) und
einen vierten Auslassströmungspfad (71a) aufweist,
die zweite Platteneinheit (54) zumindest einen stromauf liegenden Teil eines vierten
Durchströmungspfades (61Ad) aufweist, sodass Kühlmittel durch den vierten Einlassströmungspfad
(61Ac) hindurchtritt, und zumindest einen stromab liegenden Teil eines fünften Durchströmungspfades
(71b) aufweist, der dem Kühlmittel ermöglicht, durch den vierten Auslasspfad (71a)
hindurchzutreten, und wobei
ein stromab liegender Endabschnitt eines vierten Durchströmungsabschnitts (61Ad) und
ein stromauf liegender Endabschnitt des fünften Durchströmungsabschnitts (71b) miteinander
durch ein zweites Rohr (81) kommunizieren, um einen dritten Rückströmungspfad (61Ac,
61Ad, 81, 71b, 71a) zu bilden.
7. Wärmetauscher, umfassend:
die Stapelkopfteil nach einem der Ansprüche 1 bis 6;
ein erstes Wärmeleitrohr (22), das Kommunikation zwischen einem der Vielzahl an zweiten
Auslassströmungspfaden (51a) und dem ersten Einlassströmungspfad (51c) erlaubt; und
ein zweites Wärmeleitrohr (32), das Kommunikation zwischen dem ersten Auslassströmungspfad
(61a) und der ersten Vielzahl an zweiten Einlassströmungspfaden (61c) erlaubt.
8. Wärmetauscher nach Anspruch 7, wobei sowohl das erste Wärmeleitrohr (22) als auch
das zweite Wärmeleitrohr (32) ein flaches Rohr ist.
9. Klimaanlagenvorrichtung, die den Wärmetauscher (1) nach Anspruch 6 oder 8 umfasst,
wobei der Verteilungsströmungspfad (51b) verursacht, dass Kühlmittel zur Vielzahl
an zweiten Auslassströmungspfaden (51a) strömt, wenn der Wärmetauscher (1) als Verdampfer
agiert.
10. Klimaanlagenvorrichtung nach Anspruch 9, wobei das erste Wärmeleitrohr (22) auf einer
Windseite in Bezug auf das zweite Wärmeleitrohr (32) liegt, wenn der Wärmetauscher
(1) als Kondensator agiert.