Technical Field
[0001] The present invention relates to a stacking-type header, a heat exchanger, and an
air-conditioning apparatus.
Background Art
[0002] As an example of stacking-type headers according to related art, there is a stacking-type
header including a first plate-shaped unit provided with a plurality of outlet flow
passages, and a second plate-shaped unit stacked on the first plate-shaped unit and
provided with a distribution flow passage that causes refrigerant entering from an
inlet flow passage to be distributed and flow out to the outlet flow passages provided
in the first plate-shaped unit. The distribution flow passage includes a branching
flow passage with a plurality of grooves extending perpendicularly to the inflow direction
of refrigerant. Refrigerant entering the branching flow passage from the inlet flow
passage is divided into a plurality of branches while passing through the grooves,
before flow outing through the outlet flow passages provided in the first plate-shaped
unit (see, for example, Patent Literature 1).
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0004] With this type of stacking-type header, in order to reduce the thickness of plate-shaped
members that make up the second plate-shaped unit to achieve reductions in parts cost,
weight, and the like, it is necessary to reduce the cross-sectional area of the grooves.
In that case, however, pressure loss of refrigerant passing through the grooves increases.
That is, stacking-type headers according to related art have a problem in that it
is difficult to achieve reductions in parts cost, weight, and the like while minimizing
an increase in the pressure loss of refrigerant.
[0005] The present invention has been made in view of the above-mentioned problem. Accordingly,
it is an object of the present invention to provide a stacking-type header that makes
it possible to achieve reductions in parts cost, weight, and the like while minimizing
an increase in the pressure loss of refrigerant. It is another object of the present
invention to provide a heat exchanger including the stacking-type header. It is still
another object of the present invention to provide an air-conditioning apparatus including
the heat exchanger.
Solution to Problem
[0006] A stacking-type header according to the present invention includes a first plate-shaped
unit having a plurality of first outlet flow passages, and a second plate-shaped unit
stacked on the first plate-shaped unit, the second plate-shaped unit having a distribution
flow passage, the distribution flow passage causing refrigerant entering from a first
inlet flow passage to be distributed and flow out to the first outlet flow passages.
The distribution flow passage includes at least one branching flow passage, the second
plate-shaped unit has at least one first plate-shaped member, the first plate-shaped
member having at least one first projection formed by press working, and the branching
flow passage is formed as an inside of the first projection is closed in a region
other than a region where the refrigerant flows in and a region where the refrigerant
flows out. Advantageous Effects of Invention
[0007] In the stacking-type header according to the present invention, the distribution
flow passage includes at least one branching flow passage, and the second plate-shaped
unit has at least one first plate-shaped member having at least one first projection
that is formed by press working, and the branching flow passage is formed as the inside
of the first projection is closed in a region other than a region where refrigerant
flows in and a region where refrigerant flows out. Therefore, even when the first
plate-shaped member is reduced in thickness, a sufficient cross-sectional area of
the branching flow passage can be secured, thereby making it possible to achieve reductions
in parts cost, weight, and the like while minimizing an increase in the pressure loss
of refrigerant. Brief Description of Drawings
[0008]
[Fig. 1] Fig. 1 illustrates the configuration of a heat exchanger according to Embodiment
1.
[Fig. 2] Fig. 2 is a perspective view, with a stacking-type header in an exploded
state, of the heat exchanger according to Embodiment 1.
[Fig. 3] Fig. 3 is a cross-sectional view, with the stacking-type header in a stacked
state, of the heat exchanger according to Embodiment 1.
[Fig. 4] Fig. 4 is a cross-sectional view, with the stacking-type header in a stacked
state, of the heat exchanger according to Embodiment 1.
[Fig. 5] Fig. 5 is a perspective view and a cross-sectional view of main portions,
with the stacking-type header in an exploded state, of the heat exchanger according
to Embodiment 1.
[Fig. 6] Fig. 6 is a perspective view and a cross-sectional view of main portions,
with the stacking-type header in an exploded state, of the heat exchanger according
to Embodiment 1.
[Fig. 7] Fig. 7 is a development diagram of the stacking-type header of the heat exchanger
according to Embodiment 1.
[Fig. 8] Fig. 8 illustrates the configuration of an air-conditioning apparatus to
which the heat exchanger according to Embodiment 1 is applied.
[Fig. 9] Fig. 9 is a perspective view, with the stacking-type header in an exploded
state, of Modification-1 of the heat exchanger according to Embodiment 1.
[Fig. 10] Fig. 10 is a cross-sectional view, with the stacking-type header in a stacked
state, of Modification-1 of the heat exchanger according to Embodiment 1.
[Fig. 11] Fig. 11 is a development diagram of the stacking-type header of Modification-1
of the heat exchanger according to Embodiment 1.
[Fig. 12] Fig. 12 is a perspective view and a cross-sectional view of main portions,
with the stacking-type header in an exploded state, of Modification-2 of the heat
exchanger according to Embodiment 1.
[Fig. 13] Fig. 13 is a perspective view, with the stacking-type header in an exploded
state, of Modification-3 of the heat exchanger according to Embodiment 1.
[Fig. 14] Fig. 14 is a perspective view, with the stacking-type header in an exploded
state, of Modification-4 of the heat exchanger according to Embodiment 1.
[Fig. 15] Fig. 15 illustrates the configuration of a heat exchanger according to Embodiment
2.
[Fig. 16] Fig. 16 is a perspective view, with the stacking-type header in an exploded
state, of the heat exchanger according to Embodiment 2.
[Fig. 17] Fig. 17 is a development diagram of the stacking-type header of the heat
exchanger according to Embodiment 2.
[Fig. 18] Fig. 18 illustrates the configuration of an air-conditioning apparatus to
which the heat exchanger according to Embodiment 2 is applied.
[Fig. 19] Fig. 19 illustrates the configuration of a heat exchanger according to Embodiment
3.
[Fig. 20] Fig. 20 is a perspective view, with the stacking-type header in an exploded
state, of the heat exchanger according to Embodiment 3.
[Fig. 21] Fig. 21 is a development diagram of the stacking-type header of the heat
exchanger according to Embodiment 3.
[Fig. 22] Fig. 22 illustrates the configuration of an air-conditioning apparatus to
which the heat exchanger according to Embodiment 3 is applied. Description of Embodiments
[0009] Hereinafter, a stacking-type header according to the present invention will be described
with reference to the drawings.
[0010] Although the following description is directed to a case in which the stacking-type
header according to the present invention distributes refrigerant entering a heat
exchanger, the stacking-type header according to the present invention may distribute
refrigerant entering another apparatus. The configuration, operation, and the like
described below are illustrative only, and not intended to limit the present invention
to the specific configuration, operation, and the like described below. In the drawings,
the same reference signs are used to identify the same or similar elements, or reference
signs are omitted for those elements. Further, illustration of detailed structures
in the drawings will be simplified or omitted as appropriate. Further, description
of overlapping or similar features will be simplified or omitted as appropriate.
Embodiment 1
[0011] A heat exchanger according to Embodiment 1 will be described.
<Configuration of Heat Exchanger >
[0012] Hereinafter, the configuration of a heat exchanger according to Embodiment 1 will
be described.
[0013] Fig. 1 illustrates the configuration of the heat exchanger according to Embodiment
1.
[0014] As illustrated in Fig. 1, a heat exchanger 1 has a stacking-type header 2, a header
3, a plurality of first heat transfer tubes 4, and a plurality of fins 5.
[0015] The stacking-type header 2 has a refrigerant inflow part 2A, and a plurality of refrigerant
outflow parts 2B. The header 3 has a plurality of refrigerant inflow parts 3A, and
a refrigerant outflow part 3B. A refrigerant pipe is connected to the refrigerant
inflow part 2A of the stacking-type header 2 and the refrigerant outflow part 3B of
the header 3. The first heat transfer tubes 4 are connected between the refrigerant
outflow parts 2B of the stacking-type header 2 and the refrigerant inflow parts 3A
of the header 3.
[0016] The first heat transfer tube 4 is a flat tube provided with a plurality of passages.
The first heat transfer tube 4 is made of, for example, aluminum. The end portions
at the stacking-type header 2 side of the first heat transfer tubes 4 are connected
to the respective refrigerant outflow parts 2B of the stacking-type header 2. The
end portions at the stacking-type header 2 side of the first heat transfer tubes 4
may be connected to the respective refrigerant outflow parts 2B of the stacking-type
header 2 while being held by a plate-shaped holding member. The fins 5 are joined
to the first heat transfer tube 4. The fin 5 is made of, for example, aluminum. The
first heat transfer tube 4 and the fin 5 may be joined together by brazing. While
Fig. 1 depicts a case in which there are eight first heat transfer tubes 4, the present
invention is not limited to this case. Further, the present invention is not limited
to a case in which the first heat transfer tube 4 is a flat tube.
<Flow of Refrigerant in Heat Exchanger>
[0017] Hereinafter, flow of refrigerant in the heat exchanger according to Embodiment 1
will be described.
[0018] Refrigerant flowing through the refrigerant pipe flows in the stacking-type header
2 via the refrigerant inflow part 2A, and after being distributed in the stacking-type
header 2, the distributed refrigerant flows out to the first heat transfer tubes 4
via the refrigerant outflow parts 2B. In the first heat transfer tubes 4, the refrigerant
exchanges heat with air or the like supplied by a fan, for example. The refrigerant
flowing through each of the first heat transfer tubes 4 flows in the header 3 via
the refrigerant inflow parts 3A, and after merging in the header 3, the merged refrigerant
flows out to the refrigerant pipe via the refrigerant outflow part 3B. Refrigerant
flow can be reversed.
<Configuration of Stacked Header>
[0019] Hereinafter, the configuration of the stacking-type header of the heat exchanger
according to Embodiment 1 will be described.
[0020] Fig. 2 is a perspective view, with the stacking-type header in an exploded state,
of the heat exchanger according to Embodiment 1.
[0021] As illustrated in Fig. 2, the stacking-type header 2 has a first plate-shaped unit
11, and a second plate-shaped unit 12. The first plate-shaped unit 11 and the second
plate-shaped unit 12 are stacked together.
[0022] The first plate-shaped unit 11 is stacked on the refrigerant outflow side toward
which refrigerant flows out. The first plate-shaped unit 11 has a first plate-shaped
member 21, and a second plate-shaped member 22. The first plate-shaped unit 11 is
provided with a plurality of first outlet flow passages 11 A. The first outlet flow
passages 11A correspond to the refrigerant outflow parts 2B in Fig. 1.
[0023] The second plate-shaped unit 12 is stacked on the refrigerant inflow side from which
refrigerant flows in. The second plate-shaped unit 12 has a third plate-shaped member
23, and a plurality of fourth plate-shaped members 24_1 to 24_3. The second plate-shaped
unit 12 is provided with a distribution flow passage 12A. The distribution flow passage
12A has a first inlet flow passage 12a, and a plurality of branching flow passages
12b. The first inlet flow passage 12a corresponds to the refrigerant inflow part 2A
in Fig. 1.
[0024] The first plate-shaped member 21 has a first projection 21A and a second projection
21 B. The first projection 21 A and the second projection 21 B are formed by press
working such as drawing or bending, and project toward the refrigerant inflow side.
The first projection 21A has a bottom. In a state in which the first plate-shaped
member 21 is stacked, a part of an inner face 21 a of the first projection 21 A serves
as a part of the first outlet passage 11 A, and a part of an outer face 21 b of the
first projection 21A serves as a part of the branching flow passage 12b. The second
projection 21 B has a bottom, and in a state in which the first plate-shaped member
21 is stacked, the second projection 21 B serves as a joint reinforcement. The first
plate-shaped member 21 is made of, for example, aluminum.
[0025] The second plate-shaped member 22 has a first projection 22A and a second projection
22B. The first projection 22A and the second projection 22B are formed by press working
such as drawing or bending, and project toward the refrigerant inflow side. The first
projection 22A has a bottom being void. In a state in which the second plate-shaped
member 22 is stacked, an inner face 22a of the first projection 22A serves as a joint
with the first heat transfer tube 4. The second projection 22B has a bottom, and in
a state in which the second plate-shaped member 22 is stacked, the second projection
22B serves as a joint reinforcement. The second plate-shaped member 22 is made of,
for example, aluminum.
[0026] The inner face 21 a of the first projection 21 A of the first plate-shaped member
21, and the inner face 22a of the first projection 22A of the second plate-shaped
member 22 each have a shape that conforms to the outer peripheral surface of the first
heat transfer tube 4. The outer peripheral surface of the first heat transfer tube
4 is joined to the inner face 22a of the first projection 22A of the second plate-shaped
member 22 by, for example, brazing or adhesion. The bottom portion of the first projection
21 A of the first plate-shaped member 21, and an end face of the first heat transfer
tube 4 have a gap therebetween when in a joined state.
[0027] The third plate-shaped member 23 has a first projection 23A. The first projection
23A is formed by press working such as drawing or bending, and projects toward the
refrigerant inflow side. The first projection 23A has a bottom being void. In a state
in which the third plate-shaped member 23 is stacked, an inner face 23a of the first
projection 23A serves as the first inlet flow passage 12a. The third plate-shaped
member 23 is made of, for example, aluminum.
[0028] The inner face 23a of the first projection 23A of the third plate-shaped member 23
has a shape that conforms to the outer peripheral surface of the refrigerant pipe.
The outer peripheral surface of the refrigerant pipe is joined to the inner face 23a
of the first projection 23A of the third plate-shaped member 23 by, for example, brazing
or adhesion. A metal sleeve or the like may be attached to the outer face of the first
projection 23A of the third plate-shaped member 23, and the refrigerant pipe may be
connected via the metal sleeve or the like.
[0029] The fourth plate-shaped members 24_1 to 24_3 have first projections 24A_1 to 24A_3
and second projections 24B_1 to 24B_3, respectively. The first projections 24A_1 to
24A_3 and the second projections 24B_1 to 24B_3 are formed by press working such as
drawing or bending, and project toward the refrigerant inflow side. The first projection
24A_1 of the fourth plate-shaped member 24_1 has a bottom. In a state in which the
fourth plate-shaped member 24_1 is stacked, an inner face 24a_1 of the first projection
24A_1 serves as a part of the branching flow passage 12b. The first projections 24A_2
and 24A_3 of the fourth plate-shaped members 24_2 and 24_3 have a bottom. In a state
in which the fourth plate-shaped members 24_2 and 24_3 are stacked, inner faces 24a_2
and 24a_3 and outer faces 24b_2 and 24b_3 of the first projections 24A_2 and 24A_3
serve as a part of the branching flow passage 12b, respectively. The second projections
24B_1 to 24B_3 have a bottom. In a state in which the fourth plate-shaped members
24_1 to 24_3 are stacked, the second projections 24B_1 to 24B_3 serve as a joint reinforcement.
The fourth plate-shaped members 24_1 to 24_3 are made of, for example, aluminum.
[0030] Hereinafter, the fourth plate-shaped members 24_1 to 24_3 will be sometimes generically
referred to as fourth plate-shaped member 24. Hereinafter, the first projections 24A_1
to 24A_3 of the fourth plate-shaped member 24 will be sometimes generically referred
to as first projection 24A. The inner faces 24a_1 to 24a_3 of the first projection
24A of the fourth plate-shaped member 24 will be sometimes generically referred to
as inner face 24a. The outer faces 24b_1 to 24b_3 of the first projection 24A of the
fourth plate-shaped member 24 will be sometimes generically referred to as outer face
24b. The second projections 24B_1 to 24B_3 of the fourth plate-shaped member 24 will
be sometimes generically referred to as second projection 24B. Hereinafter, the first
plate-shaped member 21, the second plate-shaped member 22, the third plate-shaped
member 23, and the fourth plate-shaped member 24 will be sometimes generically referred
to as plate-shaped member. The fourth plate-shaped member 24 corresponds to "first
plate-shaped member" according to the present invention.
[0031] Figs. 3 and 4 are each a cross-sectional view, with the stacking-type header in a
stacked state, of the heat exchanger according to Embodiment 1. Fig. 3 is a cross-sectional
view taken along a line A-A in Fig. 2, and Fig. 4 is a cross-sectional view taken
along a line B-B in Fig. 2. In Figs. 3 and 4, the portion where refrigerant flows
in is shaded.
[0032] As illustrated in Figs. 3 and 4, the peripheral edge of the plate-shaped member is
bent in the stacking direction, and the distal end of the peripheral edge is joined
to the side face of the plate-shaped member that is adjacently stacked on the refrigerant
inflow side.
[0033] The inner face 24a of the first projection 24A provided in the fourth plate-shaped
member 24, and the outer face 24b or 21 b of the first projection 24A or 21A provided
in the fourth plate-shaped member 24 or the first plate-shaped member 21 adjacently
stacked on the refrigerant outflow side, are joined while being in fitting engagement
with each other, thus forming each of the branching flow passages 12b.
[0034] The inner face of the second projection 21 B or 24B provided in the first plate-shaped
member 21 or the fourth plate-shaped member 24, and the outer face of the second projection
22B, 21 B, or 24B of the second plate-shaped member 22, the first plate-shaped member
21, or the fourth plate-shaped member 24 adjacently stacked on the refrigerant outflow
side, are joined while being in fitting engagement with each other, thus forming a
reinforcement. The outer face of the second projection 24B_1 of the fourth plate-shaped
member 24_1 is joined to the surface of the third plate-shaped member 23.
[0035] Figs. 5 and 6 are each a perspective view and a cross-sectional view of main portions,
with the stacking-type header in an exploded state, of the heat exchanger according
to Embodiment 1. Figs. 5 and 6 are each a perspective view of the portion X in Fig.
2 and a cross-sectional view. Fig. 5(b) is a cross-sectional view taken along a line
C-C in Fig. 5(a), and Fig. 6(b) is a cross-sectional view taken along a line D-D in
Fig. 6(a). In Figs. 5(b) and 6(b), the portion where refrigerant flows in is shaded.
While the following description is directed to the branching flow passage 12b formed
by the inner face 24a_3 of the first projection 24A_3 of the fourth plate-shaped member
24_3 and the outer face 21 b of the first projection 21 A of the first plate-shaped
member 21, the same applies to the other branching flow passages 12b.
[0036] As illustrated in Fig. 5, the inner face of a Z-shaped region (hereinafter, a Z-shaped
region of the plate-shaped member located on the refrigerant inflow side will be generically
referred to as inflow-side Z-shaped region 12b_1 a) of the first projection 24A_3
of the fourth plate-shaped member 24_3 (hereinafter, the inner face of the inflow-side
Z-shaped region 12b_1 a will be generically referred to as inner face 12b_1 b), and
the outer face of a Z-shaped region (hereinafter, a Z-shaped region of the plate-shaped
member located on the refrigerant outflow side will be generically referred to as
outflow-side Z-shaped region 12b_2a) of the first projection 21 A of the first plate-shaped
member 21 (hereinafter, the outer face of the outflow-side Z-shaped region 12b_2a
will be generically referred to as outer face 12b_2b), are joined while being in fitting
engagement with each other, thus forming the branching flow passage 12b.
[0037] The inflow-side Z-shaped region 12b_1a has such a shape that connects two end portions
12b_1c and 12b_1d via a linear portion 12b_1e that is perpendicular to the direction
of gravity. The inflow-side Z-shaped region 12b_1a has a through-hole 12b_1f provided
at the center. Respective peripheral portions 12b_1h and 12b_1i of the two end portions
12b_1c and 12b_1d of the inflow-side Z-shaped region 12b_1a on the surface of the
fourth plate-shaped member 24_3 project toward the refrigerant outflow side.
[0038] The outflow-side Z-shaped region 12b_2a has such a shape that connects two end portions
12b_2c and 12b_2d via a linear portion 12b_2e that is perpendicular to the direction
of gravity. The two end portions 12b_2c and 12b_2d of the outflow-side Z-shaped region
12b_2a are provided with through-holes 12b_2f and 12b_2g, respectively. Respective
peripheral portions 12b_2h and 12b_2i of the two end portions 12b_2c and 12b_2d of
the outflow-side Z-shaped region 12b_2a on the first projection 21 A of the first
plate-shaped member 21 project toward the refrigerant outflow side.
[0039] The peripheral portion 12b_1h or 12b_1projecting toward the refrigerant outflow side,
and the peripheral portion 12b_2h or 12b_2i recessed toward the refrigerant outflow
side are joined while being in fitting engagement with each other. Consequently, the
refrigerant entering through the through-hole 12b_1f and divided into two branches
passes between the inner face 12b_1b of the inflow-side Z-shaped region 12b_1a and
the outer face 12b_2b of the outflow-side Z-shaped region 12b_2a without leaking,
and flows out from the through-hole 12b_2f or 12b_2g.
[0040] A protrusion 12b_2j is provided below the center of the outflow-side Z-shaped region
12b_2a in Figs. 5 and 6. The protrusion 12b_2j is joined while being in fitting engagement
with a part of the inner face of the outflow-side Z-shaped region 12b_2a of another
branching flow passage 12b adjacently located on the refrigerant outflow side, which
communicates with a part located below the center of the inflow-side Z-shaped region
12b_1a in Figs. 5 and 6. The protrusion 12b_2j prevents refrigerant entering through
the through-hole 12b_1f from leaking from the branching flow passage 12b by passing
through the inner face of the outflow-side Z-shaped region 12b_2a of another branching
flow passage 12b adjacently located on the refrigerant outflow side. The inner face
of the outflow-side Z-shaped region 12b_2a of another branching flow passage 12b adjacently
located on the refrigerant outflow side may be closed by another method.
[0041] As illustrated in Fig. 6, the peripheral portions 12b_1h and 12b_1that project toward
the refrigerant outflow side may be recessed toward the refrigerant inflow side, and
the peripheral portions 12b_2h and 12b_2i recessed toward the refrigerant outflow
side may project toward the refrigerant inflow side. In that case as well, as the
peripheral portion 12b_1h or 12b_1 projecting toward the refrigerant inflow side,
and the peripheral portion 12b_2h or 12b_2i recessed toward the refrigerant inflow
side, are joined while being in fitting engagement with each other, the refrigerant
entering through the through-hole 12b_1f and divided into two branches passes between
the inner face 12b_1b of the inflow-side Z-shaped region 12b_1a and the outer face
12b_2b of the outflow-side Z-shaped region 12b_2a without leaking, and flows out from
the through-holes 12b_2f or 12b_2g.
[0042] That is, the branching flow passage 12b divides entering refrigerant into two branches
that flow out the branching flow passage 12b. Accordingly, if there are eight first
heat transfer tubes 4 to be connected, a minimum of three fourth plate-shaped members
24 are required. If there are sixteen first heat transfer tubes 4 to be connected,
a minimum of four fourth plate-shaped members 24 are required. The number of first
heat transfer tubes 4 to be connected is not limited to a power of 2. In such a case,
a combination of the branching flow passages 12b and non-branching flow passages may
be used. The number of first heat transfer tubes 4 to be connected may be two.
[0043] To divide entering refrigerant into branches flow outing at different heights, the
end portion 12b_1c of the inflow-side Z-shaped region 12b_1a and the end portion 12b_2c
of the outflow-side Z-shaped region 12b_2a are located at different heights from the
end portion 12b_1d of the inflow-side Z-shaped region 12b_1a and the end portion 12b_2d
of the outflow-side Z-shaped region 12b_2a, respectively. In particular, if one of
the two end portions is located on the upper side in comparison to the linear portion
12b_1e of the inflow-side Z-shaped region 12b_1a and the linear portion 12b_2e of
the outflow-side Z-shaped region 12b_2a, and the other is located on the lower side
in comparison to the linear portion 12b_1e of the inflow-side Z-shaped region 12b_1a
and the linear portion 12b_2e of the outflow-side Z-shaped region 12b_2a, imbalance
of the distances along the branching flow passage 12b from the through-hole 12b_1f
to the through-hole 12b_2f and to the through-hole 12b_2g can be reduced without increasing
geometric complflow outy. The straight line connecting the through-hole 12b_2f and
the through-hole 12b_2g extends in parallel to the longitudinal direction of the plate-shaped
member. This makes it possible to reduce the size of the plate-shaped member in the
transverse direction, thus reducing parts cost, weight, and the like. Further, the
straight line connecting the through-hole 12b_2f and the through-hole 12b_2g extends
in parallel to the arrangement direction of the first heat transfer tubes 4, which
allows space saving for the heat exchanger 1.
[0044] The stacking-type header 2 is not limited to one in which the first outlet flow
passages 11A are arranged along the direction of gravity. For example, the stacking-type
header 2 may be also used for applications in which the heat exchanger 1 is disposed
in a slanted orientation, as in the case of a heat exchanger in wall-mounted room
air-conditioner's indoor units, outdoor units for air-conditioning apparatuses, and
chiller outdoor units. In that case, the inflow-side Z-shaped region 12b_1a and the
outflow-side Z-shaped region 12b_2a may have such a shape that the linear portion
12b_1e and the linear portion 12b_2e are not perpendicular to the longitudinal direction
of the plate-shaped member, respectively.
[0045] Further, the branching flow passage 12b may have another shape. That is, the branching
flow passage 12b may not be Z-shaped. For example, the inflow-side Z-shaped region
12b_1a and the outflow-side Z-shaped region 12b_2a may not have the linear portion
12b_1e and the linear portion 12b_2e, respectively. If the linear portion 12b_1e and
the linear portion 12b_2e are present, this reduces the influence of gravity when
refrigerant flows in from the through-hole 12b_1f and splits into two branches. That
is, irrespective of the flow rate and quality of the refrigerant entering in a two-phase
gas-liquid state, the influence of gravity is reduced. Consequently, the flow rate
and quality of refrigerant entering each of the first heat transfer tubes 4 can be
made uniform. Further, for example, the inflow-side Z-shaped region 12b_1a and the
outflow-side Z-shaped region 12b_2a may have a shape that branches out. If the inflow-side
Z-shaped region 12b_1a and the outflow-side Z-shaped region 12b_2a do not branch out,
the uniformity of refrigerant distribution can be improved.
[0046] The plate-shaped members may be stacked together by brazing. Stacking the plate-shaped
members together by brazing allows the plate-shaped members to be stacked without
any gap therebetween, thus minimizing leakage of refrigerant and also ensuring pressure
tightness. If the plate-shaped members are brazed together while applying pressure,
brazing failures are further reduced. If a process that promotes fillet formation,
such as forming ribs, is applied to areas susceptible to refrigerant leakages, brazing
failures are further reduced.
[0047] Further, if all of the members to be brazed together, including the first heat transfer
tube 4 and the fin 5, are made of the same material (for example, aluminum), these
members can be brazed together at once, thus improving productivity. Brazing of the
first heat transfer tube 4 and the fin 5 may be performed after brazing of the stacking-type
header 2. Further, first, only the first plate-shaped unit 11 may be joined to the
first heat transfer tube 4 by brazing, and then the second plate-shaped unit 12 may
be joined to the first heat transfer tube 4 by brazing.
<Flow of Refrigerant in Stacked Header>
[0048] Hereinafter, flow of refrigerant in the stacking-type header of the heat exchanger
according to Embodiment 1 will be described.
[0049] Fig. 7 is a development diagram of the stacking-type header of the heat exchanger
according to Embodiment 1.
[0050] As indicated by arrows in Figs. 2 and 7, the refrigerant that has passed through
the first projection 23A of the third plate-shaped member 23 passes through the through-hole
provided in the first projection 24A_1 of the fourth plate-shaped member 24_1, that
is, the through-hole 12b_1f of the inflow-side Z-shaped region 12b_1a, and flows in
the inside of the first projection 24A_1 of the fourth plate-shaped member 24_1. The
refrigerant hits the projection of a member stacked adjacent thereto, and splits into
two branches. The branched refrigerant passes between the inner face 12b_1b of the
inflow-side Z-shaped region 12b_1a and the outer face 12b_2b of the outflow-side Z-shaped
region 12b_2a, and then passes through the through-holes provided in the first projection
24A_2 of the fourth plate-shaped member 24_2, that is, the through-holes 12b_2f and
12b_2b of the outflow-side Z-shaped region 12b_2a.
[0051] The refrigerant that has passed through the through-hole provided in the first projection
24A_2 of the fourth plate-shaped member 24_2, that is, the through-hole 12b_1f of
the inflow-side Z-shaped region 12b_1a of the adjacent branching flow passage 12b,
flows in the inside of the first projection 24A_2 provided in the fourth plate-shaped
member 24_2. The refrigerant hits the projection of a member stacked adjacent thereto,
and splits into two branches. The branched refrigerant passes between the inner face
12b_1b of the inflow-side Z-shaped region 12b_1a and the outer face 12b_2b of the
outflow-side Z-shaped region 12b_2a, and then passes through the through-holes provided
in the first projection 24A_3 of the fourth plate-shaped member 24_3, that is, the
through-holes 12b_2f and 12b_2b of the outflow-side Z-shaped region 12b_2a.
[0052] The refrigerant that has passed through the through-hole provided in the first projection
24A_3 of the fourth plate-shaped member 24_3, that is, the through-hole 12b_1f of
the inflow-side Z-shaped region 12b_1a of the adjacent branching flow passage 12b,
flows in the inside of the first projection 24A_3 provided in the fourth plate-shaped
member 24_3. The refrigerant hits the projection of a member stacked adjacent thereto,
and splits into two branches. The branched refrigerant passes between the inner face
12b_1b of the inflow-side Z-shaped region 12b_1a and the outer face 12b_2b of the
outflow-side Z-shaped region 12b_2a, and then passes through the through-holes provided
in the first projection 21 A of the first plate-shaped member 21, that is, the through-holes
12b_2f and 12b_2b of the outflow-side Z-shaped region 12b_2a.
[0053] The refrigerant that has passed through the through-holes provided in the first projection
21A of the first plate-shaped member 21 passes through the first projection 22A of
the second plate-shaped member 22, and flows in the first heat transfer tube 4.
<Use of Heat Exchanger>
[0054] Hereinafter, an example of use of the heat exchanger according to Embodiment 1 will
be described.
[0055] While the following description is directed to a case in which the heat exchanger
according to Embodiment 1 is used in an air-conditioning apparatus, the present invention
is not limited to such a case. For example, the heat exchanger according to Embodiment
1 may be used in other refrigeration cycle devices having a refrigerant circuit. Further,
while the following description is directed to a case in which the air-conditioning
apparatus switches between cooling operation and heating operation, the present invention
is not limited to such a case. The air-conditioning apparatus may perform only cooling
operation or heating operation.
[0056] Fig. 8 illustrates the configuration of an air-conditioning apparatus to which the
heat exchanger according to Embodiment 1 is applied. In Fig. 8, flow of refrigerant
in cooling operation is indicated by solid arrows, and flow of refrigerant in heating
operation is indicated by dotted arrows.
[0057] As illustrated in Fig. 8, an air-conditioning apparatus 51 includes a compressor
52, a four-way valve 53, a heat source-side heat exchanger 54, an expansion device
55, a load-side heat exchanger 56, a heat source-side fan 57, a load-side fan 58,
and a controller 59. The compressor 52, the four-way valve 53, the heat source-side
heat exchanger 54, the expansion device 55, and the load-side heat exchanger 56 are
connected by the refrigerant pipe to form a refrigerant circuit.
[0058] The controller 59 is connected with, for example, the compressor 52, the four-way
valve 53, the expansion device 55, the heat source-side fan 57, the load-side fan
58, and various sensors. The controller 59 switches the flow passages of the four-way
valve 53 to switch between cooling operation and heating operation. The heat source-side
heat exchanger 54 acts as a condenser in cooling operation, and acts as an evaporator
in heating operation. The load-side heat exchanger 56 acts as an evaporator in cooling
operation, and acts as a condenser in heating operation.
[0059] Flow of refrigerant in cooling operation will be described.
[0060] Refrigerant at high pressure and high temperature in a gaseous state discharged from
the compressor 52 flows in the heat source-side heat exchanger 54 via the four-way
valve 53, where the refrigerant exchanges heat with the outside air supplied by the
heat source-side fan 57, causing the refrigerant to condense into refrigerant at high
pressure in a liquid state, which then flows out the heat source-side heat exchanger
54. The refrigerant at high pressure in a liquid state that has flow outed the heat
source-side heat exchanger 54 flows in the expansion device 55, where the refrigerant
turns into refrigerant at low pressure in a two-phase gas-liquid state. The refrigerant
at low pressure in a two-phase gas-liquid state flow outing the expansion device 55
flows in the load-side heat exchanger 56, where the refrigerant exchanges heat with
the indoor air supplied by the load-side fan 58, causing the refrigerant to evaporate
into refrigerant at low pressure in a gaseous state, which then flows out the load-side
heat exchanger 56. The refrigerant at low pressure in a gaseous state flow outing
the load-side heat exchanger 56 is sucked by the compressor 52 via the four-way valve
53.
[0061] Flow of refrigerant in heating operation will be described.
[0062] Refrigerant at high pressure and high temperature in a gaseous state discharged from
the compressor 52 flows in the load-side heat exchanger 56 via the four-way valve
53, where the refrigerant exchanges heat with the indoor air supplied by the load-side
fan 58 which causes the refrigerant to condense into refrigerant at high pressure
in a liquid state, which then flows out the load-side heat exchanger 56. The refrigerant
at high pressure in a liquid state that has flow outed the load-side heat exchanger
56 flows in the expansion device 55, where the refrigerant turns into refrigerant
at low pressure in a two-phase gas-liquid. The refrigerant at low pressure in a two-phase
gas-liquid flow outing the expansion device 55 flows in the heat source-side heat
exchanger 54 where the refrigerant exchanges heat with the outside air supplied by
the heat source-side fan 57, causing the refrigerant to condense into refrigerant
at low pressure in a gaseous state, which then flows out the heat source-side heat
exchanger 54. The refrigerant at low pressure in a gaseous state flow outing the heat
source-side heat exchanger 54 is sucked by the compressor 52 via the four-way valve
53.
[0063] The heat exchanger 1 is used in at least one of the heat source-side heat exchanger
54 and the load-side heat exchanger 56. The heat exchanger 1 is connected in such
a way that when the heat exchanger 1 acts as an evaporator, refrigerant flows in from
the stacking-type header 2, and refrigerant flows out from the header 3. That is,
when the heat exchanger 1 acts as an evaporator, refrigerant in a two-phase gas-liquid
state flows in the stacking-type header 2 from the refrigerant pipe, and refrigerant
in a gaseous state flows in the header 3 from the first heat transfer tube 4. When
the heat exchanger 1 acts as a condenser, refrigerant in a gaseous state flows in
the header 3 from the refrigerant pipe, and refrigerant in a liquid state flows in
the stacking-type header 2 from the first heat transfer tube 4.
<Operation of Heat Exchanger>
[0064] Hereinafter, operation of the heat exchanger according to Embodiment 1 will be described.
[0065] The branching flow passage 12b of the stacking-type header 2 is formed by the inner
face 12b_1b of the inflow-side Z-shaped region 12b_1 a, that is, the inner face of
the first projection of the plate-shaped member, and the outer face 12b_2b of the
outflow-side Z-shaped region 12b_2a, that is, the outer face of the first projection
of another plate-shaped member. This makes it possible to ensure a sufficient cross-sectional
area of the branching flow passage 12b even when the plate-shaped member is reduced
in thickness, thereby achieving reductions in parts cost, weight, and the like while
minimizing an increase in the pressure loss of refrigerant.
[0066] The reduced thickness of the plate-shaped member enables a reduction in thermal
capacity, which leads to shorter time required for heating and cooling performed during
joining processes such as brazing, thus improving production efficiency.
[0067] Since the projection provided in the plate-shaped member can be formed by press working
such as drawing or bending, machining cost is reduced.
[0068] Since a space is created between the plate-shaped members, in comparison to when
a passage is formed by applying cutting to a thick plate-shaped member, thermal insulation
is improved, thus minimizing heating and cooling of refrigerant passing through the
stacking-type header 2. The space between the plate-shaped members may be filled with
a heat insulating material.
[0069] The peripheral edge of the plate-shaped member is bent in the stacking direction,
and the distal end of the peripheral edge is joined to the side face of an adjacently
stacked plate-shaped member. Accordingly, in comparison to when plate-shaped members
that are not bent are stacked flat and joined together over a large area, the brazing
filler metal is easily allowed to gather tightly at the distal end of the peripheral
edge owing to surface tension. This reduces the frequency of joint failures due to
uneven application of the brazing filler metal, and the amount of the brazing filler
metal used. Further, for example, a process of finishing the joint surface into a
flat surface, and a jig for applying uniform pressure over a large area during the
brazing process become unnecessary, thus reducing manufacturing cost. That is, if
the members to be joined are brazed together in a state in which their spacing is
not uniform, the brazing filler metal becomes concentrated in areas where the spacing
is narrow, resulting in an uneven joint, a shrinkage cavity, or the like. In the stacking-type
header 2, the members to be joined have a tight spacing and a small joint surface,
which allows the brazing filler metal to gather tightly when joining these members
together, thus reducing an uneven joint, a shrinkage cavity, or the like. In particular,
if the peripheral edge of the plate-shaped member is bent obliquely in the stacking
direction as illustrated in Figs. 3 and 4, the joint area increases for improved joint
strength.
[0070] Further, the plate-shaped member is provided with the second projection, and the
inner face of the second projection is joined to the outer face of the second projection
provided in the adjacently stacked plate-shaped member. Consequently, these projections
are joined to each other in a manner similar to line contact, which allows the brazing
filler metal to easily gather tightly owing to surface tension. Therefore, the frequency
of joint failures due to uneven application of the brazing filler metal is reduced,
thus improving the reliability of reinforcement. Furthermore, the amount of the brazing
filler metal used is reduced. Further, for example, a process of finishing the joint
surface into a flat surface, and a jig for applying uniform pressure over a large
area during brazing become unnecessary, thus reducing manufacturing cost.
[0071] The inner face 12b_1b of the inflow-side Z-shaped region 12b_1 a, that is, the inner
face of the first projection of the plate-shaped member, and the outer face 12b_2b
of the outflow-side Z-shaped region 12b_2a, that is, the outer face of the first projection
of another plate-shaped member, are joined while being in fitting engagement with
each other. Consequently, these projections are joined to each other in a manner similar
to line contact, which allows the brazing filler metal to easily gather tightly owing
to surface tension. Therefore, the frequency of joint failures due to uneven application
of the brazing filler metal, and the amount of the brazing filler metals used are
reduced. Further, for example, a process of finishing the joint surface into a flat
surface, and a jig for applying uniform pressure over a large area during brazing
become unnecessary, thus reducing manufacturing cost. Furthermore, it is impossible
to join the plate-shaped members together by changing their stacking order, thus reducing
the risk of the plate-shaped members being stacked in the wrong order.
<Modification-1>
[0072] Fig. 9 is a perspective view, with the stacking-type header in an exploded state,
of Modification-1 of the heat exchanger according to Embodiment 1. Fig. 10 is a cross-sectional
view, with the stacking-type header in a stacked state, of Modification-1 of the heat
exchanger according to Embodiment 1. Fig. 11 is a development diagram of the stacking-type
header in Modification-1 of the heat exchanger according to Embodiment 1. Fig. 10
is a cross-sectional view taken along a line E-E in Fig. 9. In Fig. 10, the portion
where refrigerant flows in is shaded. Fig. 11 illustrates a state in which the first
plate-shaped member 21, the second plate-shaped member 22, the third plate-shaped
member 23, and the fourth plate-shaped member 24, and fifth plate-shaped members 25_1
to 25_5 are joined to each other.
[0073] As illustrated in Figs. 9 to Fig. 11, the fifth plate-shaped members 25_1 to 25_5
may be joined to the first plate-shaped member 21, the second plate-shaped member
22, the third plate-shaped member 23, and the fourth plate-shaped member 24. The plate-shaped
member has the first projection 21A, 22A, 23A, or 24A, which is formed by press working
such as drawing or bending and projects toward the refrigerant inflow side. The first
projection 21 A, 22A, 23A, or 24A has a bottom being void, and in a state in which
the plate-shaped member is stacked, its inner face 21 a, 22a, 23a or 24a serves as
a part of the branching flow passage 12b. Hereinafter, the fifth plate-shaped members
25_1 to 25_5 will be sometimes generically referred to as fifth plate-shaped member
25. The fifth plate-shaped member 25 corresponds to "second plate-shaped member" according
to the present invention.
[0074] The fifth plate-shaped members 25_1 to 25_5 are provided with through-holes 25A_1
to 25A_5, respectively. The outer periphery at the distal end of each of the first
projections 21 A, 22A, 23A, and 24A is joined to the corresponding one of the through-holes
25A_1 to 25A_5 while being in fitting engagement with the corresponding through-hole.
When the plate-shaped members are stacked together, the inside of the first projection
21A, 22A, 23A, or 24A is closed in a region other than the region where refrigerant
flows in and the region where refrigerant flows out, by the surface of the fifth plate-shaped
member 25 stacked on the refrigerant outflow side, and the surface of another plate-shaped
member stacked on the refrigerant inflow side, thus forming the branching flow passage
12b.
<Modification-2>
[0075] Fig. 12 is a perspective view and a cross-sectional view of main portions, with the
stacking-type header in an exploded state, of Modification-2 of the heat exchanger
according to Embodiment 1. Fig. 12(a) is a perspective view of main portions with
the stacking-type header in an exploded state, and Fig. 12(b) is a cross-sectional
view of the first plate-shaped member 21 taken along a line F-F in Fig. 12(a). In
Fig. 12(b), the portion where refrigerant flows in is shaded.
[0076] As illustrated in Fig. 12, a region of the inner face 21 a of the first projection
21A of the first plate-shaped member 21 other than the outflow-side Z-shaped region
12b_2a may have such a shape that gradually widens toward the refrigerant outflow
side. With this configuration, if the first heat transfer tube 4 is a flat tube, the
pressure loss of refrigerant as the refrigerant passes through the first outlet passage
11A is reduced.
<Modification-3>
[0077] Fig. 13 is a perspective view, with the stacking-type header in an exploded state,
of Modification-3 of the heat exchanger according to Embodiment 1.
[0078] As illustrated in Fig. 13, the third plate-shaped member 23 may be provided with
a plurality of first inlet flow passages 12a to reduce the number of fourth plate-shaped
members 24. This configuration allows reductions in parts cost, weight, and the like.
<Modification-4>
[0079] Fig. 14 is a perspective view, with the stacking-type header in an exploded state,
of Modification-4 of the heat exchanger according to Embodiment 1.
[0080] As illustrated in Fig. 14, the first inlet flow passage 12a may be provided in a
plate-shaped member other than the third plate-shaped member 23. In that case, a through-hole
may be provided in another plate-shaped member, and a projection for introducing refrigerant
from the through-hole to the inner face 24a_1 of the first projection 24A_1 of the
fourth plate-shaped member 24_1 may be provided in another plate-shaped member and
a neighboring plate-shaped member. That is, the present invention encompasses configurations
in which the first inlet flow passage 12a is provided in the first plate-shaped unit
11, and the "distribution flow passage" according to the present invention encompasses
distribution flow passages other than the distribution flow passage 12A that has the
first inlet flow passage 12a provided in the second plate-shaped unit 12.
Embodiment 2
[0081] A heat exchanger according to Embodiment 2 will be described.
[0082] In the following, description of features that overlap with or are similar to those
of Embodiment 1 will be simplified or omitted as appropriate.
<Configuration of Heat Exchanger>
[0083] Hereinafter, the configuration of a heat exchanger according to Embodiment 2 will
be described.
[0084] Fig. 15 illustrates the configuration of a heat exchanger according to Embodiment
2.
[0085] As illustrated in Fig. 15, a heat exchanger 1 has a stacking-type header 2, a plurality
of first heat transfer tubes 4, and a plurality of fins 5.
[0086] The stacking-type header 2 has a refrigerant inflow part 2A, a plurality of refrigerant
outflow parts 2B, a plurality of refrigerant inflow parts 2C, and a refrigerant outflow
part 2D. A refrigerant pipe is connected to the refrigerant inflow part 2A of the
stacking-type header 2 and the refrigerant outflow part 2D of the stacking-type header
2. The first heat transfer tube 4 is a flat tube with a hair pin bend. The first heat
transfer tubes 4 are connected between the refrigerant outflow parts 2B of the stacking-type
header 2 and the refrigerant inflow parts 2C of the stacking-type header 2.
<Flow of Refrigerant in Heat Exchanger>
[0087] Hereinafter, flow of refrigerant in the heat exchanger according to Embodiment 2
will be described.
[0088] Refrigerant flowing through the refrigerant pipe flows in the stacking-type header
2 via the refrigerant inflow part 2A, and after being distributed in the stacking-type
header 2, the distributed refrigerant flows out to the first heat transfer tubes 4
via the refrigerant outflow parts 2B. In the first heat transfer tubes 4, the refrigerant
exchanges heat with air or the like supplied by a fan, for example. The refrigerant
that has passed through each of the first heat transfer tubes 4 flows in the stacking-type
header 2 via the refrigerant inflow parts 2C, and after merging in the stacking-type
header 2, the merged refrigerant flows out to the refrigerant pipe via the refrigerant
outflow part 2D. Refrigerant flow can be reversed.
<Configuration of Stacked Header >
[0089] Hereinafter, the configuration of the stacking-type header of the heat exchanger
according to Embodiment 2 will be described.
[0090] Fig. 16 is a perspective view, with the stacking-type header in an exploded state,
of the heat exchanger according to Embodiment 2. Fig. 17 is a development diagram
of the stacking-type header of the heat exchanger according to Embodiment 2.
[0091] As illustrated in Figs. 16 and 17, the stacking-type header 2 has a first plate-shaped
unit 11, and a second plate-shaped unit 12. The first plate-shaped unit 11 and the
second plate-shaped unit 12 are stacked together.
[0092] The first plate-shaped unit 11 is provided with a plurality of first outlet flow
passages 11 A, and a plurality of second inlet flow passages 11 B. The first plate-shaped
unit 11 has a first plate-shaped member 21, a sixth plate-shaped member 26, and a
second plate-shaped member 22. The second inlet flow passages 11 B correspond to the
refrigerant inflow parts 2C in Fig. 15. Hereinafter, the first plate-shaped member
21, the second plate-shaped member 22, a third plate-shaped member 23, a fourth plate-shaped
member 24, and the sixth plate-shaped member 26 will be sometimes generically referred
to as plate-shaped member.
[0093] The second plate-shaped unit 12 is provided with a distribution flow passage 12A,
and a joining flow passage 12B. The joining flow passage 12B has a mixing passage
12c, and a second outlet flow passage 12d. The second outlet flow passage 12d corresponds
to the refrigerant outflow part 2D in Fig. 15.
[0094] The second plate-shaped member 22 has a third projection 22C, which is formed by,
for example, press working such as drawing or bending and projects toward the refrigerant
outflow side. The third projection 22C has a bottom being void only in a region connected
to the refrigerant outflow-side end portion of the first heat transfer tube 4. In
a state in which the second plate-shaped member 22 is stacked, an outer face 22d of
the third projection 22C serves as a part of the second inlet flow passage 11 B.
[0095] The sixth plate-shaped member 26 has a first projection 26A, a second projection
26B, and a third projection 26C, which are formed by, for example, press working such
as drawing or bending and project toward the refrigerant outflow side. The third projection
26C has a bottom being void in a region that is not opposed to the refrigerant outflow-side
end portion of the first heat transfer tube 4. In a state in which the sixth plate-shaped
member 26 is stacked, an inner face 26c of the third projection 26C serves as a part
of the second inlet flow passage 11 B.
[0096] The first plate-shaped member 21 has, for example, a through portion 21C, which
is formed by press working and does not project to neither the refrigerant outflow
side nor the refrigerant inflow side. In a state in which the first plate-shaped member
21 is stacked, the through portion 21C serves as a part of the second inlet flow passage
11 B.
[0097] The fourth plate-shaped member 24 has, for example, third projections 24C_1 to 24C_3,
which are formed by press working such as drawing or bending and project toward the
refrigerant inflow side. Hereinafter, the third projections 24C_1 to 24C_3 of the
fourth plate-shaped member 24 will be sometimes generically referred to as third projection
24C. The third projection 24C has a bottom being void, and in a state in which the
fourth plate-shaped member 24 is stacked, inner faces 24c_1 to 24c_3 of the third
projection 24C serve as a part of the mixing passage 12c. Hereinafter, the inner faces
24c_1 to 24c_3 of the third projection 24C of the fourth plate-shaped member 24 will
be sometimes generically referred to as inner face 24c.
[0098] The third plate-shaped member 23 has, for example, a third projection 23C and a fourth
projection 23D. The third projection 23C is formed by press working such as drawing
or bending, and projects toward the refrigerant inflow side. The fourth projection
23D, which is provided in the third projection 23C, projects toward the refrigerant
outflow side. The third projection 23C has a bottom. In a state in which the third
plate-shaped member 23 is stacked, an outer face 23d of the third projection 23C serves
as a part of the mixing passage 12c. The fourth projection 23D has a bottom being
void. In a state in which the third plate-shaped member 23 is stacked, an inner face
23e of the fourth projection 23D serves as the second outlet flow passage 12d.
[0099] The second outlet flow passage 12d may be provided in a plate-shaped member other
than the third plate-shaped member 23. In that case, a through-hole may be provided
in another plate-shaped member, and a projection for introducing refrigerant to the
through-hole may be provided in another plate-shaped member and a neighboring plate-shaped
member. That is, the present invention encompasses configurations in which the second
outlet flow passage 12d is provided in the first plate-shaped unit 11, and the "joining
flow passage" according to the present invention encompasses joining flow passages
other than the joining flow passage 12B that has the second outlet flow passage 12d
provided in the second plate-shaped unit 12.
<Flow of Refrigerant in Stacked Header>
[0100] Hereinafter, flow of refrigerant in the stacking-type header of the heat exchanger
according to Embodiment 2 will be described.
[0101] As indicated by arrows in Figs. 16 and 17, after passing through the first heat transfer
tube 4, refrigerant passes through the third projection 22C of the second plate-shaped
member 22, and flows in the inside of the third projection 26C of the sixth plate-shaped
member 26. After entering the inside of the third projection 26C of the sixth plate-shaped
member 26, the refrigerant passes through the through portion 21C of the first plate-shaped
member 21, and flows in the inside of the third projection 24C of the fourth plate-shaped
member 24 where the refrigerant is mixed with another flow. The mixed refrigerant
passes through the fourth projection 23D of the third plate-shaped member 23, and
flows out to the refrigerant pipe.
<Use of Heat Exchanger>
[0102] Hereinafter, an example of use of the heat exchanger according to Embodiment 2 will
be described.
[0103] Fig. 18 illustrates the configuration of an air-conditioning apparatus to which the
heat exchanger according to Embodiment 2 is applied.
[0104] As illustrated in Fig. 18, the heat exchanger 1 is used for at least one of a heat
source-side heat exchanger 54 and a load-side heat exchanger 56. The heat exchanger
1 is connected in such a way that when the heat exchanger 1 acts as an evaporator,
refrigerant flows in the first heat transfer tube 4 from the distribution flow passage
12A of the stacking-type header 2, and refrigerant flows in the joining flow passage
12B of the stacking-type header 2 from the first heat transfer tube 4. That is, when
the heat exchanger 1 acts as an evaporator, refrigerant in a two-phase gas-liquid
state flows in the distribution flow passage 12A of the stacking-type header 2 from
the refrigerant pipe, and refrigerant in a gaseous state flows in the joining flow
passage 12B of the stacking-type header 2 from the first heat transfer tube 4. When
the heat exchanger 1 acts as a condenser, refrigerant in a gaseous state flows in
the joining flow passage 12B of the stacking-type header 2 from the refrigerant pipe,
and refrigerant in a liquid state flows in the distribution flow passage 12A of the
stacking-type header 2 from the first heat transfer tube 4.
<Operation of Heat Exchanger>
[0105] Hereinafter, operation of the heat exchanger according to Embodiment 2 will be described.
[0106] In the stacking-type header 2, the first plate-shaped unit 11 is provided with the
second inlet flow passages 11 B, and the second plate-shaped unit 12 is provided with
the joining flow passage 12B. Consequently, a header 3 becomes unnecessary, thus reducing,
for example, parts cost of the heat exchanger 1. Since the header 3 is not required,
it is possible to extend the first heat transfer tube 4 to increase the number of
fins 5, that is, increase the mounting volume of the heat exchange unit of the heat
exchanger 1.
Embodiment 3
[0107] Hereinafter, a heat exchanger according to Embodiment 3 will be described.
[0108] A description of features that overlap with or are similar to those of Embodiment
1 and Embodiment 2 will be simplified or omitted as appropriate.
<Configuration of Heat Exchanger>
[0109] Hereinafter, the configuration of the heat exchanger according to Embodiment 3 will
be described.
[0110] Fig. 19 illustrates the configuration of the heat exchanger according to Embodiment
3.
[0111] As illustrated in Fig. 19, a heat exchanger 1 has a stacking-type header 2, a plurality
of first heat transfer tubes 4, a plurality of second heat transfer tubes 6, and a
plurality of fins 5.
[0112] The stacking-type header 2 has a plurality of refrigerant turn-around parts 2E. Like
the first heat transfer tube 4, the second heat transfer tube 6 is a flat tube with
a hair pin bend. The first heat transfer tubes 4 are connected between a plurality
of refrigerant outflow parts 2B and the refrigerant turn-around parts 2E of the stacking-type
header 2, and the second heat transfer tubes 6 are connected between the refrigerant
turn-around parts 2E and a plurality of refrigerant inflow parts 2C of the stacking-type
header 2.
<Flow of Refrigerant in Heat Exchanger>
[0113] Hereinafter, flow of refrigerant in the heat exchanger according to Embodiment 3
will be described.
[0114] Refrigerant flowing through the refrigerant pipe flows in the stacking-type header
2 via a refrigerant inflow part 2A, and after being distributed in the stacking-type
header 2, the distributed refrigerant flows out to the first heat transfer tubes 4
via the refrigerant outflow parts 2B. In the first heat transfer tubes 4, the refrigerant
exchanges heat with air or the like supplied by a fan, for example. The refrigerant
that has passed through the first heat transfer tubes 4 flows in the refrigerant turn-around
parts 2E of the stacking-type header 2 where the refrigerant is turned around before
flow outing to the second heat transfer tubes 6. In the second heat transfer tubes
6, the refrigerant exchanges heat with air or the like supplied by a fan, for example.
The refrigerant that has passed through each of the second heat transfer tubes 6 flows
in the stacking-type header 2 via the refrigerant inflow parts 2C, and after merging
in the stacking-type header 2, the merged refrigerant flows out to the refrigerant
pipe via a refrigerant outflow part 2D. Refrigerant flow can be reversed.
<Configuration of Stacked Header>
[0115] Hereinafter, the configuration of the stacking-type header of the heat exchanger
according to Embodiment 3 will be described.
[0116] Fig. 20 is a perspective view, with the stacking-type header in an exploded state,
of the heat exchanger according to Embodiment 3. Fig. 21 is a development diagram
of the stacking-type header of the heat exchanger according to Embodiment 3.
[0117] As illustrated in Figs. 20 and 21, the stacking-type header 2 has a first plate-shaped
unit 11, and a second plate-shaped unit 12. The first plate-shaped unit 11 and the
second plate-shaped unit 12 are stacked together.
[0118] The first plate-shaped unit 11 is provided with a plurality of first outlet flow
passages 11 A, a plurality of second inlet flow passages 11B, and a plurality of turn-back
flow passages 11C. The turn-back flow passages 11C correspond to the refrigerant turn-around
parts 2E in Fig. 19.
[0119] A second plate-shaped member 22 has a third projection 22C and a fourth projection
22D. The third projection 22C is formed by, for example, press working such as drawing
or bending, and projects toward the side opposite to the side from which the refrigerant
from the first heat transfer tube 4 flows in. The fourth projection 22D is formed
by, for example, press working such as drawing or bending, and projects toward the
side to which the refrigerant from the second heat transfer tube 6 flows out. The
fourth projection 22D has a bottom being void only in regions that are connected to
the refrigerant outflow-side end portion of the first heat transfer tube 4 and the
refrigerant inflow-side end portion of the second heat transfer tube 6. In a state
in which the second plate-shaped member 22 is stacked, an outer face 22f of the fourth
projection 22D serves as a part of the turn-back flow passage 11C.
[0120] A sixth plate-shaped member 26 has a third projection 26C and a fourth projection
26D. The third projection 26C is formed by, for example, press working such as drawing
or bending, and projects toward the side opposite to the side from which refrigerant
from the first heat transfer tube 4 flows in. The fourth projection 26D is formed
by, for example, press working such as drawing or bending, and projects toward the
side to which refrigerant from the second heat transfer tube 6 flows out. The fourth
projection 26D has a bottom. In a state in which the sixth plate-shaped member 26
is stacked, an inner face 26e of the fourth projection 26D serves as a part of the
turn-back flow passage 11C.
<Flow of Refrigerant in Stacked Header>
[0121] Hereinafter, flow of refrigerant in the stacking-type header of the heat exchanger
according to Embodiment 3 will be described.
[0122] As indicated by arrows in Figs. 20 and 21, after passing through the first heat transfer
tube 4, refrigerant passes through the fourth projection 22D of the second plate-shaped
member 22, and flows in the inside of the fourth projection 26D of the sixth plate-shaped
member 26. After entering the inside of the fourth projection 26D of the sixth plate-shaped
member 26, the refrigerant passes through the fourth projection 22D of the second
plate-shaped member 22 again, and flows in the second heat transfer tube 6. The refrigerant
that has passed through the second heat transfer tube 6 passes through the third projection
22C of the second plate-shaped member 22 and the third projection 26C of the sixth
plate-shaped member 26, and flows in the inside of a third projection 24C of a fourth
plate-shaped member 24 where the refrigerant is mixed with another flow. The mixed
refrigerant passes through the fourth projection 23D of the third plate-shaped member
23, and flows out to the refrigerant pipe.
<Use of Heat Exchanger>
[0123] Hereinafter, an example of use of the heat exchanger according to Embodiment 3 will
be described.
[0124] Fig. 22 illustrates the configuration of an air-conditioning apparatus to which the
heat exchanger according to Embodiment 2 is applied.
[0125] As illustrated in Fig. 22, the heat exchanger 1 is used for at least one of a heat
source-side heat exchanger 54 and a load-side heat exchanger 56. The heat exchanger
1 is connected in such a way that when the heat exchanger 1 acts as an evaporator,
refrigerant flows in the first heat transfer tube 4 from a distribution flow passage
12A of the stacking-type header 2, and refrigerant flows in a joining flow passage
12B of the stacking-type header 2 from the second heat transfer tube 6. That is, when
the heat exchanger 1 acts as an evaporator, refrigerant in a two-phase gas-liquid
state flows in the distribution flow passage 12A of the stacking-type header 2 from
the refrigerant pipe, and refrigerant in a gaseous state flows in the joining flow
passage 12B of the stacking-type header 2 from the second heat transfer tube 6. When
the heat exchanger 1 acts as a condenser, refrigerant in a gaseous state flows in
the joining flow passage 12B of the stacking-type header 2 from the refrigerant pipe,
and refrigerant in a liquid state flows in the distribution flow passage 12A of the
stacking-type header 2 from the first heat transfer tube 4.
[0126] Further, the heat exchanger 1 is disposed so that when the heat exchanger 1 acts
as a condenser, the first heat transfer tube 4 is located on the upstream side of
airflow produced by the heat source-side fan 57 or the load-side fan 58 (upstream
side of airflow), in comparison to the second heat transfer tube 6. That is, the flow
of refrigerant from the second heat transfer tube 6 to the first heat transfer tube
4 and the airflow are opposed to each other. The temperature of refrigerant in the
first heat transfer tube 4 is lower than that of refrigerant in the second heat transfer
tube 6. The temperature of the airflow produced by the heat source-side fan 57 or
the load-side fan 58 is lower on the upstream side of the heat exchanger 1 than on
the downstream side of the heat exchanger 1. As a result, in particular, refrigerant
can be subcooled (so-called subcooling) by the low-temperature airflow flowing on
the upstream side of the heat exchanger 1, thereby improving condenser performance.
The heat source-side fan 57 and the load-side fan 58 may be provided on either of
the upstream side of airflow and the downstream side of airflow.
<Operation of Heat Exchanger>
[0127] Hereinafter, the configuration of the heat exchanger according to Embodiment 3 will
be described.
[0128] In the heat exchanger 1, the first plate-shaped unit 11 is provided with the turn-back
flow passages 11C, and the second heat transfer tubes 6 are connected in addition
to the first heat transfer tubes 4. For example, the amount of heat exchange can be
increased by increasing the area of the heat exchanger 1 as seen in front view. However,
in that case, the size of the housing that contains the heat exchanger 1 increases.
Further, the amount of heat exchange can be increased by increasing the number of
fins 5 by reducing the spacing of the fins 5. However, in that case, it is difficult
to make the spacing of the fins 5 less than about 1 mm from the viewpoints of drainage
performance, frosting performance, and dust-proofness. Consequently, a sufficient
increase in the amount of heat exchange may not be attained in some cases. In contrast,
increasing the number of rows of heat transfer tubes as in the case of the heat exchanger
1 makes it possible to increase the amount of heat exchange without changing the area
of the heat exchanger 1 as seen in front view, the spacing of the fins 5, or the like.
Increasing the number of rows of heat transfer tubes to two increases the amount of
heat exchange by more than about 1.5 times. The number of rows of heat transfer tubes
may be increased to three or more. Further, the area of the heat exchanger 1 as seen
in front view, the spacing of the fins 5, or the like may be changed.
[0129] The header (the stacking-type header 2) is provided only on one side of the heat
exchanger 1. If the heat exchanger 1 is disposed in such a way that, in order to increase
the mounting volume of its heat exchange unit, for example, the heat exchanger 1 is
bent along a plurality of side faces of the housing that contains the heat exchanger
1, each row of heat transfer tubes differs in the radius of curvature of its bent
portion, which causes the end portions of individual rows of heat transfer tubes to
become misaligned. When a header (the stacking-type header 2) is provided only on
one side of the heat exchanger 1 as in the case of the stacking-type header 2, even
if the end portions of individual rows of heat transfer tubes become out of alignment,
only the end portions on one side needs to be aligned, thus enabling improvements
in terms of the freedom of design, production efficiency, and the like in comparison
to when headers (the stacking-type header 2 and the header 3) are provided on both
sides of the heat exchanger 1 as in the case of the heat exchanger according to Embodiment
1. In particular, it also becomes possible to bend the heat exchanger 1 after joining
each member of the heat exchanger 1, thus enabling a further improvement in production
efficiency.
[0130] Further, when the heat exchanger 1 acts as a condenser, the first heat transfer tube
4 is located on the upstream side of airflow in comparison to the second heat transfer
tube 6. When headers (the stacking-type header 2 and a header 3) are provided on both
sides of the heat exchanger 1 as in the case of the heat exchanger according to Embodiment
1, it is difficult to improve the condenser performance of the heat exchanger by providing
a difference in the temperature of refrigerant between each row of heat transfer tubes.
In particular, if each of the first heat transfer tube 4 and the second heat transfer
tube 6 is a flat tube, unlike a circular tube, the limited freedom of bending means
that it is difficult to provide a refrigerant temperature difference between each
row of heat transfer tubes by deforming refrigerant passages. In contrast, if the
first heat transfer tube 4 and the second heat transfer tube 6 are connected to the
stacking-type header 2 as in the case of the heat exchanger 1, a difference in refrigerant
temperature is naturally created between each row of heat transfer tubes. Consequently,
the refrigerant flow and the airflow can be opposed to each other easily without deforming
refrigerant passages.
[0131] While Embodiments 1 to 3 have been described above, the present invention is not
limited to the embodiments described above. For example, the whole or part of each
of the embodiments, modifications, and the like may be combined.
Reference Signs List
[0132] 1 heat exchanger 2 stacking-type header 2A refrigerant inflow part 2B refrigerant
outflow part 2C refrigerant inflow part 2D refrigerant outflow part 2E refrigerant
turn-around part 3 header 3A refrigerant inflow part 3B refrigerant outflow part 4
first heat transfer tube 5 fin 6 second heat transfer tube 11 first plate-shaped unit
11 A first outlet passage 11 B second inlet flow passage 11C turn-back flow passage
12 second plate-shaped unit 12A distribution flow passage 12B joining flow passage
12a first inlet flow passage 12b branching flow passage 12b_1a inflow-side Z-shaped
region 12b_2a outflow-side Z-shaped region 12b_1b inner face of inflow-side Z-shaped
region 12b_2b outer face of outflow-side Z-shaped region 12b_1 c, 12b_2c, 12b_1 d,
12b_2d end portion of Z-shaped region 12b_1e, 12b_2e linear portion of Z-shaped region
12b_1f, 12b_2f, 12b_2g through-hole12b_1h, 12b_2h, 12b_1i, 12b_2i peripheral portion
12b_2j protrusion 12c mixing passage 12d second outlet flow passage 21 first plate-shaped
member 21A first projection 21 B second projection 21C through portion 21 a inner
face of first projection 21 b outer face of first projection 22 second plate-shaped
member 22A first projection 22B second projection 22C third projection 22D fourth
projection 22a inner face of first projection 22c inner face of third projection 22d
outer face of third projection 22f outer face of fourth projection 23 third plate-shaped
member 23A first projection 23C third projection 23D fourth projection 23a inner face
of first projection 23d outer face of third projection 23e inner face of fourth projection
24,24_1 to 24_3 fourth plate-shaped member 24A, 24A_1 to 24A_3 first projection 24B,
24B_1 to 24B_3 second projection 24C, 24C_1 to 24C_3 third projection 24a, 24a_1 to
24a_3 inner face of first projection 24b, 24b_1 to 24b_3 outer face of first projection
24c, 24c_1 to 24c_3 inner face of third projection 25,25_1 to 25_5 fifth plate-shaped
member 25A_1 to 25A_5 through-hole26 sixth plate-shaped member 26A first projection
26B second projection 26C third projection 26D fourth projection 26c inner face of
third projection 26e inner face of fourth projection 51 air-conditioning apparatus
52 compressor 53 four-way valve 54 heat source-side heat exchanger 55 expansion device
56 load-side heat exchanger57 heat source-side fan 58 load-side fan 59 controller