FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
HEAT EXCHANGER AND REFRIGERATION CYCLE APPARATUS;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION
ORGANISED AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE
ADDRESS IS 7-3, MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 1008310,
JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED
2
DESCRIPTION
TECHNICAL FIELD
[0001] The present disclosure relates to a heat exchanger and a refrigeration cycle
5 apparatus.
BACKGROUND ART
[0002] Japanese Patent Laying-Open No. 2015-113983 discloses a heat exchanger
including: a first heat exchange element having a plurality of first flat tubes; a second
heat exchange element having a plurality of second flat tubes; and a folded header at
10 which refrigerant having passed through the first heat exchange element is turned and
introduced into the second heat exchange element.
CITATION LIST
PATENT LITERATURE
[0003] PTL 1: Japanese Patent Laying-Open No. 2015-113983
15 SUMMARY OF INVENTION
TECHNICAL PROBLEM
[0004] In the above-mentioned heat exchanger, since each of the first flat tubes and
each of the second flat tubes are disposed at the same height in the vertical direction,
one of each first flat tube and each second flat tube is located downstream of the other
20 in the ventilation direction. In other words, in the ventilation direction, the flat tubes
disposed on the downstream side are located in the dead water zone formed behind the
flat tubes disposed on the upstream side. As a result, in the above-mentioned heat
exchanger, the heat exchange performance of the heat exchange element disposed
downstream in the ventilation direction cannot be sufficiently exhibited.
25 [0005] A main object of the present disclosure is to provide a heat exchanger enhanced
in heat exchange performance as compared with the above-mentioned conventional
heat exchanger, and a refrigeration cycle apparatus including the heat exchanger.
SOLUTION TO PROBLEM
[0006] A heat exchanger according to a first aspect of the present disclosure includes: a
3
first heat exchange portion and a second heat exchange portion arranged side by side in
a first direction intersecting with a direction of gravity. The first heat exchange
portion has: a plurality of first fins extending in the direction of gravity and arranged
side by side in a second direction intersecting with the direction of gravity and the first
5 direction; and a plurality of first flat tubes mounted to intersect with each of the first
fins and arranged side by side in the direction of gravity. The second heat exchange
portion has: a plurality of second fins extending in the direction of gravity and arranged
side by side in the second direction; and a plurality of second flat tubes mounted to
intersect with each of the second fins and arranged side by side in the direction of
10 gravity. The heat exchanger further includes: a first header connected to a first end of
each of the first flat tubes; a second header connected to a first end of each of the
second flat tubes; and a third header connected to a second end of each of the first flat
tubes and a second end of each of the second flat tubes. When viewed in the first
direction, each of the second flat tubes is disposed not to overlap with each of the first
15 flat tubes. The third header has: a first plate provided with a plurality of first insertion
holes through which the second ends of the first flat tubes are respectively inserted, and
a plurality of second insertion holes through which the second ends of the second flat
tubes are respectively inserted; and a second plate provided with a plurality of
communication spaces each communicating with a corresponding one of the first
20 insertion holes and a corresponding one of the second insertion holes.
[0007] A heat exchanger according to a second aspect of the present disclosure
includes a first heat exchange portion and a second heat exchange portion arranged side
by side in a first direction intersecting with a direction of gravity. The first heat
exchange portion has: a plurality of first fins extending in the direction of gravity and
25 arranged side by side in a second direction intersecting with the direction of gravity and
the first direction; and a plurality of first flat tubes mounted to intersect with each of the
first fins and arranged side by side in the direction of gravity. The second heat
exchange portion has: a plurality of second fins extending in the direction of gravity
and arranged side by side in the second direction; and a plurality of second flat tubes
4
mounted to intersect with each of the second fins and arranged side by side in the
direction of gravity. The heat exchanger further includes: a first header connected to a
first end of each of the first flat tubes; a second header connected to a first end of each
of the second flat tubes; and a third header connected to a second end of each of the
5 first flat tubes and a second end of each of the second flat tubes, the third header being
provided with a plurality of communication spaces each communicating with a
corresponding one of the first flat tubes and a corresponding one of the second flat
tubes. When viewed in the first direction, each of the second flat tubes is disposed not
to overlap with each of the first flat tubes. At least one of the first flat tubes that is
10 connected to one communication space of the communication spaces is located lower
in the direction of gravity than at least one of the second flat tubes that is connected to
the one communication space.
ADVANTAGEOUS EFFECTS OF INVENTION
[0008] The present disclosure can provide a heat exchanger improved in heat exchange
15 performance as compared with the above-mentioned conventional heat exchanger, and
a refrigeration cycle apparatus including the heat exchanger.
BRIEF DESCRIPTION OF DRAWINGS
[0009] Fig. 1 is a top view of a heat exchanger according to a first embodiment.
Fig. 2 is a front view of the heat exchanger shown in Fig. 1.
20 Fig. 3 is a side view of the heat exchanger shown in Fig. 1.
Fig. 4 is a partial cross-sectional view for illustrating configurations of a first fin,
a first flat tube, a second fin, and a second flat tube in the heat exchanger shown in Fig.
1.
Fig. 5 is a diagram for illustrating a first plate of a bridging header shown in Fig.
25 1.
Fig. 6 is a diagram for illustrating a second plate of the bridging header shown
in Fig. 1.
Fig. 7 is a diagram for illustrating a third plate of the bridging header shown in
Fig. 1.
5
Fig. 8 is an exploded perspective view for illustrating a connection relation
among the first plate, the second plate, and the third plate of the bridging header shown
in Fig. 1.
Fig. 9 is a partial cross-sectional view taken along a line indicated by an arrow
5 IX-IX in Fig. 1.
Fig. 10 is a partial cross-sectional view showing a modification of the first plate,
the second plate, and the third plate shown in Fig. 9.
Fig. 11 is a partial cross-sectional view for illustrating configurations of a first
fin, a first flat tube, a second fin, and a second flat tube in a heat exchanger according
10 to a second embodiment.
Fig. 12 is a diagram for illustrating a first plate of a bridging header in the heat
exchanger according to the second embodiment.
Fig. 13 is a diagram for illustrating a second plate of the heat exchanger
according to the second embodiment.
15 Fig. 14 is a top view of a heat exchanger according to a third embodiment.
Fig. 15 is a front view of the heat exchanger shown in Fig. 14.
Fig. 16 is a side view of the heat exchanger shown in Fig. 14.
Fig. 17 is a diagram for illustrating a first plate of a bridging header shown in
Fig. 14.
20 Fig. 18 is a diagram for illustrating a second plate of the bridging header shown
in Fig. 14.
Fig. 19 is a diagram for illustrating a third plate of the bridging header shown in
Fig. 14.
DESCRIPTION OF EMBODIMENTS
25 [0010] The following describes embodiments as examples of a heat exchanger
according to the present disclosure with reference to the accompanying drawings. In
the accompanying drawings, the same or corresponding portions are denoted by the
same reference characters, and the description thereof will not be repeated. Further, in
each of the figures, for convenience of explanation, an X direction, a Y direction, and a
6
Z direction orthogonal to each other are introduced. The X direction and the Y
direction corresponds to the horizontal direction while the Z direction corresponds to
the direction of gravity.
[0011] First Embodiment
5 As shown in Figs. 1 to 3, a heat exchanger 100 according to the first
embodiment includes a first heat exchange portion 11, a second heat exchange portion
12, a first header 13, a second header 14, and a third header (hereinafter, referred to as a
bridging header) 15.
[0012] As shown in Figs. 1, 2, and 4, each of first heat exchange portion 11 and second
10 heat exchange portion 12 is provided so as to exchange heat between the refrigerant
flowing in the X direction (the second direction) and air flowing in the Y direction.
First heat exchange portion 11 and second heat exchange portion 12 are arranged side
by side in the Y direction (the first direction). In the following description, in the Y
direction, the upstream side in the ventilation direction will be simply referred to as a
15 windward side while the downstream side in the ventilation direction will be simply
referred to as a leeward side. First heat exchanging portion 11 is disposed on the
windward side relative to second heat exchanging portion 12.
[0013] As shown in Figs. 1, 2, and 4, first heat exchange portion 11 includes a plurality
of first fins 1 and a plurality of first flat tubes 2. The plurality of first fins 1 extend in
20 the Z direction and the Y direction, and are arranged side by side in the X direction.
Each of first fins 1 is a plate fin. The plurality of first flat tubes 2 are mounted to
intersect with each of the plurality of first fins 1, and are arranged side by side in the Z
direction. The cross-sectional shape of each first flat tube 2 perpendicular to the X
direction is a flat shape having a long-side direction and a short-side direction. The
25 long-side direction of each first flat tube 2 corresponds to the Y direction. In first heat
exchange portion 11, heat is exchanged between: air flowing in the Y direction between
first fins 1 adjacent to each other; and the refrigerant flowing in the X direction through
each first flat tube 2. A plurality of flow paths are formed inside each first flat tube 2.
The flow paths each extend in the axial direction (the X direction) of each first flat tube
7
2 and are arranged side by side in the long-side direction of each first flat tube 2.
[0014] As shown in Figs. 1, 2, and 4, second heat exchange portion 12 includes a
plurality of second fins 3 and a plurality of second flat tubes 4. The plurality of
second fins 3 extend in the Z direction and the Y direction, and are arranged side by
5 side in the X direction. Each second fin 3 is a plate fin. The plurality of second flat
tubes 4 are mounted to intersect with each of the plurality of second fins 3 and are
arranged side by side in the Z direction. The cross-sectional shape of each second flat
tube 4 perpendicular to the X direction is a flat shape having a long-side direction and a
short-side direction. In second heat exchange portion 12, heat is exchanged between:
10 air flowing in the Y direction between second fins 3 adjacent to each other; and the
refrigerant flowing in the X direction through each second flat tube 4. A plurality of
flow paths are formed inside each second flat tube 4. The flow paths each extend in
the axial direction (the X direction) of each second flat tube 4 and are arranged side by
side in the long-side direction of each second flat tube 4.
15 [0015] As shown in Figs. 1 and 4, each second fin 3 is spaced apart in the Y direction
from each first fin 1. Each second fin 3 is disposed on the leeward side relative to
each first fin 1. An end portion 3A located on the windward side of each second fin 3
is disposed on the leeward side relative to an end portion 1B located on the leeward
side of each first fin 1.
20 [0016] As shown in Figs. 1 and 4, each second flat tube 4 is spaced apart in the Y
direction from each first flat tube 2. Each second flat tube 4 is disposed on the
leeward side relative to each first flat tube 2. An end portion located on the windward
side of each second flat tube 4 is disposed on the leeward side relative to an end portion
located on the leeward side of each first flat tube 2.
25 [0017] As shown in Fig. 2, each second fin 3 is disposed to overlap with each first fin 1
when viewed in the Y direction. Each second fin 3 is formed as a member separate
from each first fin 1.
[0018] As shown in Figs. 2 and 4, each second flat tube 4 is disposed not to overlap
with each first flat tube 2 when viewed in the Y direction. When viewed in the Y
8
direction, each first flat tube 2 is disposed between two second flat tubes 4 adjacent to
each other in the Z direction. When viewed in the Y direction, each second flat tube 4
is disposed between two first flat tubes 2 adjacent to each other in the Z direction.
[0019] As shown in Fig. 4, each first fin 1 has a continuous portion 1D disposed on one
5 side (for example, on the windward side) in the Y direction and extending in the Z
direction. Each first fin 1 is provided with a plurality of insertion holes 1C disposed
on the other side (for example, on the leeward side) in the Y direction with respect to
continuous portion 1D. Through each insertion hole 1C, each first flat tube 2 is
inserted. Continuous portion 1D is located between an end portion 1A located on the
10 windward side of first fin 1 and an end portion located on the windward side of each
insertion hole 1C. Each insertion hole 1C is opened, for example, at end portion 1B
located on the leeward side of first fin 1. Note that each insertion hole 1C may not be
opened at end portion 1B located on the leeward side of first fin 1.
[0020] As shown in Fig. 4, each second fin 3 has a continuous portion 3D disposed on
15 one side (for example, on the windward side) in the Y direction and extending in the Z
direction. Each second fin 3 is provided with a plurality of insertion holes 3C
disposed on the other side (for example, on the leeward side) in the Y direction with
respect to continuous portion 3D. Through each insertion hole 3C, each second flat
tube 4 is inserted. Continuous portion 3D is located between end portion 3A located
20 on the windward side of second fin 3 and the end portion located on the windward side
of each insertion hole 3C. Each insertion hole 3C is opened, for example, at an end
portion 3B located on the leeward side of second fin 3. Each insertion hole 3C may
not be opened at end portion 3B located on the leeward side of second fin 3.
[0021] As shown in Figs. 1 and 2, first header 13 is connected to a first end of each
25 first flat tube 2 in the Y direction. First header 13 allows merging of the refrigerant
having flowed out of each first flat tube 2 or allows splitting of the refrigerant that is to
flow into each first flat tube 2. Second header 14 is connected to the first end of each
second flat tube 4 in the Y direction, and allows merging of the refrigerant having
flowed out of each second flat tube 4 or allows splitting of the refrigerant that is to flow
9
into each second flat tube 4. Second header 14 is disposed on the leeward side
relative to first header 13.
[0022] As shown in Figs. 1 to 3, bridging header 15 is connected to the second end of
each first flat tube 2 and the second end of each second flat tube 4. Bridging header
5 15 provides communication between each first flat tube 2 and each second flat tube 4
for refrigerant to flow therebetween.
[0023] As shown in Fig. 3, bridging header 15 is provided with: a plurality of first
insertion holes 16 through which first flat tubes 2 are respectively inserted; a plurality
of second insertion holes 17 through which second flat tubes 4 are respectively
10 inserted; and a plurality of communication spaces 18 each communicating with a
corresponding one of first insertion holes 16 and a corresponding one of second
insertion holes 17. First insertion holes 16 are arranged side by side in the Z direction.
Second insertion holes 17 are arranged side by side in the Z direction. Each second
insertion hole 17 is spaced apart in the Y direction from each first insertion hole 16.
15 Further, each second insertion hole 17 is spaced apart in the Z direction from each first
insertion hole 16.
[0024] As shown in Figs. 3 and 6, each communication space 18 is provided to allow
communication between one first insertion hole 16 and one second insertion hole 17
that is disposed adjacent to this one first insertion hole 16 in the Z direction and located
20 above this one first insertion hole 16. In other words, each communication space 18
provides communication between one first flat tube 2 and one second flat tube 4 that is
disposed adjacent to this one first flat tube 2 in the Z direction and located above this
one first flat tube 2, for refrigerant to flow therebetween.
[0025] As shown in Fig. 3, bridging header 15 includes a first plate 15A, a second plate
25 15B, and a third plate 15C. First plate 15A, second plate 15B, and third plate 15C are
stacked in the X direction. First plate 15A is disposed on the side close to first heat
exchange portion 11 and second heat exchange portion 12 with respect to second plate
15B and third plate 15C in the X direction. Third plate 15C is disposed on the side
opposite to first heat exchange portion 11 and second heat exchange portion 12 with
10
respect to first plate 15A and second plate 15B in the X direction. Second plate 15B
is sandwiched between first plate 15A and third plate 15C in the X direction. First
plate 15A, second plate 15B, and third plate 15C are connected and fixed to each other
in a water-tight manner. The materials forming first plate 15A, second plate 15B, and
5 third plate 15C include aluminum (Al), for example.
[0026] As shown in Figs. 3, 5, and 8, first plate 15A is provided with a plurality of
through holes. The through holes provided in first plate 15A constitute first insertion
holes 16 or second insertion holes 17. In other words, first insertion holes 16 and
second insertion holes 17 are provided as through holes in first plate 15A. First
10 insertion holes 16 and second insertion holes 17 each may be formed by any method
and, for example, are formed by press working. First plate 15A serves as a connection
plate connected to each first flat tube 2 and each second flat tube 4 in a water-tight
manner.
[0027] As shown in Figs. 3, 6, and 8, second plate 15B is provided with a plurality of
15 through holes. The inner space of each through hole provided in second plate 15B
provides communication space 18. In other words, each communication space 18 is
an inner space of each of the plurality of through holes provided in second plate 15B.
When viewed in the X direction, each through hole provided in second plate 15B is
provided to overlap with the entirety of one first insertion hole 16 and one second
20 insertion hole 17. When viewed in the X direction, the opening end of each through
hole provided in second plate 15B is located outside each of the opening ends of each
first insertion hole 16 and each second insertion hole 17 provided in first plate 15A.
Each through hole provided in second plate 15B may be formed by any method and, for
example, are formed by press working. Second plate 15B is a flow path plate
25 providing communication space 18 as a refrigerant flow path between first flat tube 2
and second flat tube 4.
[0028] As shown in Figs. 3 and 6, one first flat tube 2 connected to one communication
space 18 is located lower in the Z direction than one second flat tube 4 connected to
this one communication space 18. Specifically, the uppermost portion of one first flat
11
tube 2 connected to one communication space 18 is located at the same height in the Z
direction as the lowermost portion of one second flat tube 4 connected to this one
communication space 18, or located lower than the lowermost portion.
[0029] The inner circumferential surface of each through hole provided in second plate
5 15B has a pair of inclined surfaces facing each other in the Z direction and inclined
with respect to the X direction and the Y direction. The pair of inclined surfaces is
inclined gradually upward to the leeward side. The distance between the pair of
inclined surfaces in the Z direction is larger than the width of each first insertion hole
16 in the Z direction and the width of each second insertion hole 17 in the Z direction.
10 [0030] As shown in Figs. 3, 7, and 8, third plate 15C is disposed on the side opposite to
each first insertion hole 16 and each second insertion hole 17 with respect to each
communication space 18, and closes one end of each communication space 18 in the X
direction. In third plate 15C, no through hole is formed in a region overlapping with
communication space 18 when viewed in the X direction. Third plate 15C forms what
15 is called an outer shell plate.
[0031] As shown in Fig. 9, first plate 15A is smaller in thickness than second plate 15B.
Third plate 15C is smaller in thickness than second plate 15B. First plate 15A is
larger in thickness than third plate 15C, for example. First flat tube 2 is fixed to first
plate 15A, for example, by a brazing material. In this case, after first flat tube 2 is
20 inserted into first insertion hole 16 and second flat tube 4 is inserted into second
insertion hole 17, first flat tube 2 and second insertion hole 17 are fixed to first plate
15A by a brazing material. Then, second plate 15B and third plate 15C are fixed to
first plate 15A by a brazing material. In this way, each first flat tube 2, each second
flat tube 4, and bridging header 15 are connected and fixed to each other in a water25 tight manner.
[0032]
In heat exchanger 100, each of second flat tubes 4 is disposed not to overlap
with each of first flat tubes 2 when viewed in the Y direction. In other words, in heat
exchanger 100, each second flat tube 4 disposed on the leeward side is not located in
12
the dead water zone of each first flat tube 2 disposed on the windward side. Thus, the
heat exchange performance of heat exchanger 100 is enhanced as compared with the
heat exchange performance of the heat exchanger in which each first flat tube and each
second flat tube are disposed at the same height in the vertical direction.
5 [0033] Further, bridging header 15 of heat exchanger 100 includes: first plate 15A
provided with first insertion holes 16 through which the second ends of first flat tubes 2
are respectively inserted and second insertion holes 17 through which the second ends
of second flat tubes 4 are respectively inserted; and second plate 15B provided with
communication spaces 18 each communicating with a corresponding one of first
10 insertion holes 16 and a corresponding one of second insertion holes 17.
[0034] In bridging header 15 as described above, each of first plate 15A and second
plate 15B formed of separate plate members is provided with: first insertion holes 16
and second insertion holes 17 through which first flat tubes 2 and second flat tubes 4
are respectively inserted; and communication spaces 18 each providing communication
15 between each first flat tube 2 and each second flat tube 4 for refrigerant to flow
therebetween. Thus, the degree of freedom for the shapes of each first insertion hole
16, each second insertion hole 17, and each communication space 18 in bridging header
15 is enhanced as compared with the degree of freedom for the shape of the bridging
header in which each first insertion hole, each second insertion hole, and each
20 communication space are formed in one member. As a result, in bridging header 15,
even when each second flat tube 4 is disposed not to overlap with each first flat tube 2
when viewed in the Y direction, the insertion margins for each first insertion hole 16
and each second insertion hole 17 can be readily ensured and the volume of each
communication space 18 can be readily increased, as compared with the bridging
25 header in which each first insertion hole, each second insertion hole, and each
communication space are provided in one member.
[0035] As a result, in heat exchanger 100 including bridging header 15 described above,
the heat exchange performance can be readily enhanced as compared with the heat
exchanger including the bridging header in which each first insertion hole, each second
13
insertion hole, and each communication space are provided in one member.
[0036] In heat exchanger 100, first plate 15A is smaller in thickness than second plate
15B. This makes it possible to simultaneously increase the volume of each
communication space 18 and the insertion margins for each first insertion hole 16 and
5 each second insertion hole 17, as compared with the case in which the thickness of first
plate 15A is equal to or larger than the thickness of second plate 15B.
[0037] In heat exchanger 100, one first flat tube 2 connected to one communication
space 18 is located lower in the Z direction than one second flat tube 4 connected to
this one communication space 18.
10 [0038] In this way, when refrigerant flows from second flat tube 4 to first flat tube 2
through communication space 18, gravity acts on this refrigerant in the flow direction
of the refrigerant. In such heat exchanger 100, as compared with the heat exchanger
in which each first flat tube and each second flat tube are disposed at the same height in
the vertical direction, the pressure loss of the gas-liquid two-phase refrigerant having
15 flowed out of second flat tube 4 is reduced, so that the heat exchange performance is
enhanced.
[0039]
Each communication space 18 only needs to provide communication between at
least one first flat tube 2 and at least one second flat tube 4 for refrigerant to flow
20 therebetween. Each communication space 18 may be formed, for example, to provide
communication between the plurality of first flat tubes 2 and the plurality of second flat
tubes 4 for refrigerant to flow therebetween.
[0040] Second plate 15B may be provided with a plurality of recesses in place of the
plurality of through holes. In this case, each communication space 18 is formed of an
25 inner space of a recess provided in second plate 15B. Bridging header 15 may not
include third plate 15C and may be formed as a multilayer body of first plate 15A and
second plate 15B.
[0041] As shown in Fig. 10, a plurality of recesses 15D may be provided in the surface
of third plate 15C on the side close to second plate 15B. Each of the plurality of
14
recesses 15D is provided to overlap with each of the through holes provided in second
plate 15B when viewed in the X direction. The region of third plate 15C where no
recess 15D is provided is formed to overlap with the region of second plate 15B where
no through hole is provided when viewed in the X direction. In this case, the inner
5 space of each recess 15D provided in third plate 15C communicates with the inner
space of each through hole provided in second plate 15B, and each communication
space 18 is formed of the above-mentioned two inner spaces.
[0042] In bridging header 15, second plate 15B may be configured as a multilayer body
formed of a plurality of plates. As long as the entire thickness of second plate 15B is
10 larger than the thickness of first plate 15A, the thickness of each plate forming second
plate 15B may be equal to or smaller than the thickness of first plate 15A.
[0043] In this way, the pressure resistance of second plate 15B can be enhanced
without impairing the formability of second plate 15B as compared with the case in
which second plate 15B is formed as one plate.
15 [0044] Further, in bridging header 15, the plurality of first insertion holes 16, the
plurality of second insertion holes 17, and the plurality of communication spaces 18
may be provided in one member. Bridging header 15 as described above may be
formed by laser processing, for example.
[0045] Second Embodiment
20 A heat exchanger according to the second embodiment has basically the same
configuration and exhibits basically the same effect as those of heat exchanger 100
according to the first embodiment, but is different from heat exchanger 100 in that each
first flat tube 2 and each second flat tube 4 have upper surfaces 2A and 4A, respectively,
inclined with respect to the horizontal direction and that each communication space 18
25 extends along upper surfaces 2A and 4A, as shown in Figs. 11 to 13.
[0046] The angle formed by upper surface 2A with respect to the horizontal direction is
5 degrees or more and 45 degrees or less, for example. The angle formed by upper
surface 4A with respect to the horizontal direction is 5 degrees or more and 45 degrees
or less, for example. The angle formed by upper surface 2A of first flat tube 2 with
15
respect to the horizontal direction is, for example, equal to the angle formed by upper
surface 4A of second flat tube 4 with respect to the horizontal direction. Upper
surface 2A of one first flat tube 2 connected to one communication space 18 is, for
example, disposed to be flush with upper surface 4A of one second flat tube 4
5 connected to this one communication space 18.
[0047] In the heat exchanger according to the second embodiment, each first flat tube 2
and each second flat tube 4 have upper surfaces 2A and 4A, respectively, inclined with
respect to the horizontal direction, and each communication space 18 extends along
upper surfaces 2A and 4A, and thereby, imbalance in distribution of the refrigerant
10 from communication space 18 to the flow paths of first flat tubes 2 is suppressed.
[0048] Note that modifications similar to those of the heat exchanger according to the
first embodiment are allowable also in the heat exchanger according to the second
embodiment.
[0049] Third Embodiment
15 A heat exchanger 101 according to the third embodiment has basically the same
configuration and exhibits basically the same effect as those of heat exchanger 100
according to the first embodiment, but is different from heat exchanger 100 in that
bridging header 15 is divided into a plurality of sections as shown in Figs. 14 to 16.
[0050] Bridging header 15 is divided into a first bridging header 19 disposed above in
20 the Z direction and a second bridging header 20 disposed below in the Z direction.
The plurality of first flat tubes 2 are divided into first flat tubes 2 of a first group
disposed above and first flat tubes 2 of a second group disposed below first flat tubes 2
of the first group. The plurality of second flat tubes 4 are divided into second flat
tubes 4 of a first group disposed above and second flat tubes 4 of a second group
25 disposed below second flat tubes 4 of the first group.
[0051] First bridging header 19 is connected to each of the second ends of first flat
tubes 2 of the first group and each of the second ends of second flat tubes 4 of the first
group, and allows merging of the refrigerant having flowed out of each of second flat
tubes 4 of the first group and also allows splitting of the refrigerant that is to flow into
16
each of first flat tubes 2 of the first group.
[0052] Second bridging header 20 is connected to each of the second ends of first flat
tubes 2 of the second group and each of the second ends of second flat tubes 4 of the
second group, and allows merging of the refrigerant having flowed out of each of
5 second flat tubes 4 of the second group and also allows splitting of the refrigerant that
is to flow into each of first flat tubes 2 of the second group.
[0053] First bridging header 19 includes a first plate 19A, a second plate 19B, and a
third plate 19C. First plate 19A, second plate 19B, and third plate 19C have the same
configurations as those of first plate 15A, second plate 15B, and third plate 15C
10 described above.
[0054] Second bridging header 20 includes a first plate 20A, a second plate 20B, and a
third plate 20C. First plate 20A, second plate 20B, and third plate 20C have the same
configurations as those of first plate 15A, second plate 15B, and third plate 15C
described above.
15 [0055] First plates 19A and 20A are configured as plate members different from each
other, for example. Second plates 19B and 20B are configured as plate members
different from each other, for example. Third plates 19C and 20C are configured as
plate members different from each other, for example. Note that first plates 19A and
20A may be configured as one plate member. Second plates 19B and 20B may be
20 configured as one plate member. Third plates 19C and 20C may be configured as one
plate member, for example.
[0056] As shown in Fig. 16, a plurality of through holes are provided in each of first
plates 19A and 20A. Each through hole provided in each of first plates 19A and 20A
constitutes a first insertion hole 21 or a second insertion hole 22. In other words, each
25 first insertion hole 21 and each second insertion hole 22 are provided as a through hole
in each of first plates 19A and 20A.
[0057] As shown in Fig. 17, second plates 19B and 20B each are provided with a
plurality of through holes. The inner space of each through hole provided in each of
second plates 19B and 20B provides a communication space 23. Each communication
17
space 23 is an inner space of each of the plurality of through holes provided in each of
second plates 19B and 20B. When viewed in the X direction, each through hole
provided in each of second plates 19B and 20B is formed to overlap with the entirety of
one first insertion hole 21 and one second insertion hole 22. When viewed in the X
5 direction, the opening end of each through hole provided in each of second plates 19B
and 20B is located outside each of the opening ends of each first insertion hole 21 and
each second insertion hole 22 provided in each of first plates 19A and 20A.
[0058] As shown in Figs. 16 and 18, one first flat tube 2 connected to one
communication space 23 is located lower in the Z direction than one second flat tube 4
10 connected to this one communication space 23. Specifically, the uppermost portion of
one first flat tube 2 connected to one communication space 18 is disposed at the same
height in the Z direction as the lowermost portion of one second flat tube 4 connected
to this one communication space 18, or located lower than the lowermost portion.
[0059] The inner circumferential surface of each through hole provided in each of
15 second plates 19B and 20B has a pair of inclined surfaces facing each other in the Z
direction and inclined with respect to the X direction and the Y direction. The pair of
inclined surfaces is inclined gradually upward to the leeward side. The distance
between the pair of inclined surfaces in the Z direction is larger than the width of each
first insertion hole 21 in the Z direction and the width of each second insertion hole 22
20 in the Z direction.
[0060] As shown in Figs. 15 and 19, third plates 19C and 20C each are disposed on the
side opposite to each first insertion hole 21 and each second insertion hole 22 with
respect to each communication space 23, and close one end of each communication
space 23 in the X direction. In each of third plates 19C and 20C, no through hole is
25 provided in a region overlapping with communication space 23 when viewed in the X
direction.
[0061] Note that modifications similar to those of the heat exchanger according to the
first embodiment are allowable also in heat exchanger 101 according to the third
embodiment.
18
[0062] Fourth Embodiment

A refrigeration cycle apparatus 200 according to the fourth embodiment
includes any one of the heat exchangers according to the first to third embodiments as
5 an evaporator. Refrigeration cycle apparatus 200 mainly includes a compressor 111,
heat exchangers 100, 101, a heat exchanger 113, and an expansion valve 114. In
refrigeration cycle apparatus 200, second header 14 serves as an inflow portion of
refrigerant, and first header 13 serves as an outflow portion of refrigerant. In each of
heat exchangers 100 and 101 serving as evaporators, the refrigerant flows through
10 second header 14, second heat exchange portion 12, bridging header 15, first heat
exchange portion 11, and first header 13 in this order. The gas-liquid two-phase
refrigerant that has been condensed in heat exchanger 113 and then decompressed by
expansion valve 114 flows into second header 14. The gas-liquid two-phase
refrigerant exchanges heat with air flowing in the Y direction through second heat
15 exchange portion 12 and first heat exchange portion 11 and thereby evaporates and
turns into gas-phase refrigerant. This gas-phase refrigerant flows out of first header
13 and is suctioned into compressor 111. Note that refrigeration cycle apparatus 200
may further include a four-way valve 112 for switching the flow direction of the
refrigerant. Four-way valve 112 switches the operation mode between an operation
20 mode in which heat exchanger 100, 101 serves as an evaporator and an operation mode
in which heat exchanger 100, 101 serves as a condenser.
[0063] Although the embodiments of the present disclosure have been described as
above, the above-described embodiments can also be variously modified. Further, the
scope of the present disclosure is not limited to the above-described embodiments.
25 The scope of the present disclosure is defined by the terms of the claims and is intended
to include any modifications within the meaning and scope equivalent to the terms of
the claims.
REFERENCE SIGNS LIST
[0064] 1 first fin, 1A, 1B, 3A, 3B end portion, 1C, 3C insertion hole, 1D, 3D
19
continuous portion, 2 first flat tube, 2A, 4A upper surface, 3 second fin, 4 second flat
tube, 11 first heat exchange portion, 12 second heat exchange portion, 13 first header,
14 second header, 15 bridging header, 15A, 19A, 20A first plate, 15B, 19B, 20B
second plate, 15C, 19C, 20C third plate, 15D recess, 16, 21 first insertion hole, 17, 22
5 second insertion hole, 18, 23 communication space, 19 first bridging header, 20 second
bridging header, 100, 101 heat exchanger.
20
We Claim:
1. A heat exchanger comprising:
a first heat exchange portion and a second heat exchange portion arranged side
5 by side in a first direction intersecting with a direction of gravity,
the first heat exchange portion having
a plurality of first fins extending in the direction of gravity and arranged
side by side in a second direction intersecting with the direction of gravity and the first
direction, and
10 a plurality of first flat tubes mounted to intersect with each of the first
fins and arranged side by side in the direction of gravity,
the second heat exchange portion having
a plurality of second fins extending in the direction of gravity and
arranged side by side in the second direction, and
15 a plurality of second flat tubes mounted to intersect with each of the
second fins and arranged side by side in the direction of gravity,
the heat exchanger further comprising:
a first header connected to a first end of each of the first flat tubes;
a second header connected to a first end of each of the second flat tubes; and
20 a third header connected to a second end of each of the first flat tubes and a
second end of each of the second flat tubes, wherein
when viewed in the first direction, each of the second flat tubes is disposed not
to overlap with each of the first flat tubes, and
the third header has
25 a first plate provided with a plurality of first insertion holes through
which the second ends of the first flat tubes are respectively inserted, and a plurality of
second insertion holes through which the second ends of the second flat tubes are
respectively inserted, and
a second plate provided with a plurality of communication spaces each
21
communicating with a corresponding one of the first insertion holes and a
corresponding one of the second insertion holes.
2. The heat exchanger according to claim 1, wherein at least one of the first
5 flat tubes that is connected to one communication space of the communication spaces is
located lower in the direction of gravity than at least one of the second flat tubes that is
connected to the one communication space.
3. A heat exchanger comprising:
10 a first heat exchange portion and a second heat exchange portion arranged side
by side in a first direction intersecting with a direction of gravity,
the first heat exchange portion having
a plurality of first fins extending in the direction of gravity and arranged
side by side in a second direction intersecting with the direction of gravity and the first
15 direction, and
a plurality of first flat tubes mounted to intersect with each of the first
fins and arranged side by side in the direction of gravity,
the second heat exchange portion having
a plurality of second fins extending in the direction of gravity and
20 arranged side by side in the second direction, and
a plurality of second flat tubes mounted to intersect with each of the
second fins and arranged side by side in the direction of gravity,
the heat exchanger further comprising:
a first header connected to a first end of each of the first flat tubes;
25 a second header connected to a first end of each of the second flat tubes; and
a third header connected to a second end of each of the first flat tubes and a
second end of each of the second flat tubes, the third header being provided with a
plurality of communication spaces each communicating with a corresponding one of
the first flat tubes and a corresponding one of the second flat tubes, wherein
22
when viewed in the first direction, each of the second flat tubes is disposed not
to overlap with each of the first flat tubes, and
at least one of the first flat tubes that is connected to one communication space
of the communication spaces is located lower in the direction of gravity than at least
5 one of the second flat tubes that is connected to the one communication space.
4. The heat exchanger according to claim 3, wherein
the third header has
a first plate provided with a plurality of first insertion holes through
10 which the second ends of the first flat tubes are respectively inserted, and a plurality of
second insertion holes through which the second ends of the second flat tubes are
respectively inserted, and
a second plate provided with the communication spaces.
15 5. The heat exchanger according to any one of claims 1, 2, and 4, wherein the
first plate is smaller in thickness than the second plate.
6. The heat exchanger according to any one of claims 1, 2, 4, and 5, wherein
the second plate is configured as a multilayer body formed of a plurality of plate
20 members.
7. The heat exchanger according to any one of claims 1 to 6, wherein
each of the first flat tubes and the second flat tubes has an upper surface
inclined with respect to a horizontal direction, and
25 each of the communication spaces extends along the upper surface.
8. The heat exchanger according to any one of claims 1 to 7, wherein
each of the first fins and the second fins has a continuous portion disposed on
one side in the first direction and extending in the direction of gravity,
23
each of the first fins and the second fins is provided with a plurality of insertion
holes disposed on the other side in the first direction with respect to the continuous
portion, each of the first flat tubes or each of the second flat tubes being inserted
through a corresponding one of the insertion holes, and
5 the first heat exchange portion and the second heat exchange portion are
disposed such that the first direction extends in a ventilation direction and the
continuous portion is located upstream from the insertion holes in the ventilation
direction.
10 9. A refrigeration cycle apparatus comprising the heat exchanger according to
any one of claims 1 to 8 as an evaporator.