U.S. patent application number 11/037467 was filed with the patent office on 2005-08-11 for heat exchanger.
This patent application is currently assigned to CALSONIC KANSEI CORPORATION. Invention is credited to Funatsu, Takumi, Iwasaka, Koichi, Kawada, Tsutomu, Takai, Toru, Tamura, Hiroyuki, Tsuchiya, Minoru.
Application Number | 20050173100 11/037467 |
Document ID | / |
Family ID | 34636984 |
Filed Date | 2005-08-11 |
United States Patent
Application |
20050173100 |
Kind Code |
A1 |
Takai, Toru ; et
al. |
August 11, 2005 |
Heat exchanger
Abstract
A heat exchanger comprises outer fins; a plurality of tubes
arranged alternately with the outer fins; and header tanks
receiving open ends of the tubes for communication with the tubes.
The header tanks each comprise a first member and a second member
which are combined to each other. The first member has tube
insertion slots into which the open ends of the tubes are inserted,
the second member does not have the tube insertion slots. The first
member is either a core material having no brazing material layers
on outer and inner peripheral surfaces thereof, or a core material
having a brazing material layer on an outer peripheral surface
thereof but having no brazing material layer on an inner peripheral
surface thereof. The second member is brazed to the outer or inner
peripheral surface of the first member having no brazing material
layer thereon.
Inventors: |
Takai, Toru; (Ashikaga-shi,
JP) ; Iwasaka, Koichi; (Tatebayashi-shi, JP) ;
Tamura, Hiroyuki; (Sano-shi, JP) ; Tsuchiya,
Minoru; (Tatebayashi-shi, JP) ; Funatsu, Takumi;
(Tatebayashi-shi, JP) ; Kawada, Tsutomu;
(Ashikaga-shi, JP) |
Correspondence
Address: |
FOLEY AND LARDNER
SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
CALSONIC KANSEI CORPORATION
|
Family ID: |
34636984 |
Appl. No.: |
11/037467 |
Filed: |
January 19, 2005 |
Current U.S.
Class: |
165/149 ;
165/174 |
Current CPC
Class: |
F28F 21/084 20130101;
F28F 9/0224 20130101; F28F 2275/04 20130101 |
Class at
Publication: |
165/149 ;
165/174 |
International
Class: |
F28F 009/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 20, 2004 |
JP |
P 2004-11689 |
Jan 23, 2004 |
JP |
P2004-15959 |
Jan 29, 2004 |
JP |
P 2004-21566 |
Claims
1. A heat exchanger comprising; outer fins; a plurality of tubes
having open ends and arranged alternately with the outer fins; and
header tanks receiving the open ends of the tubes for communication
with the tubes, the header tanks each comprising a first member and
a second member which are combined to each other; wherein the first
member includes tube insertion slots into which the open ends of
the tubes are inserted, the second member lacking the tube
insertion slots; the first member is either a core material having
no brazing material layers on outer and inner peripheral surfaces
thereof, or a core material having a brazing material layer on an
outer peripheral surface thereof which does not have brazing
material layer on an inner peripheral surface thereof; and the
second member is brazed to the outer or inner peripheral surface of
the first member which does not have brazing material layer
thereon.
2. A heat exchanger as set forth in claim 1, wherein the first
member is the core material which does not have brazing material
layers on the outer and inner peripheral surfaces thereof.
3. A heat exchanger as set forth in claim 2, wherein the second
member has a brazing material layer on the inner or outer
peripheral surface thereof to be joined to the first member.
4. A heat exchanger as set forth in claim 3, wherein: the second
member is provided with the brazing material layer on the outer
surface of a core material; and the first and second members are
brazed together with an outer peripheral surface of the second
member connected to an inner peripheral surface of the first
member.
5. A heat exchanger as set forth in claim 3, wherein; the second
member is provided with the brazing material layer on the inner
peripheral surface of a core material; and the first and second
members are brazed together with an outer peripheral surface of the
first member connected to an inner peripheral surface of the second
member.
6. A heat exchanger as set forth in claim 5, wherein the second
member is provided with the brazing material layers on the inner
and outer peripheral surfaces of a core material.
7. A heat exchanger as set forth in claim 2, wherein the first
member and the second member of the header tank each have a box
shape with an opening formed in a combining direction.
8. A heat exchanger as set forth in claim 7, wherein: the header
tank includes a partition for partitioning an interior thereof into
a plurality of chambers; and the partition is provided with the
brazing material layer on at least one surface of a core material
having two surfaces.
9. A heat exchanger as set forth in claim 2, wherein: the header
tank includes a pipe comprising the first member and the second
member, and lids for closing opposite open ends of the pipe; and
the lids each have a brazing material layer on at least one surface
of a core material having two surfaces.
10. A heat exchanger as set forth in claim 9, wherein: the header
tank includes a partition for partitioning an interior thereof into
a plurality of chambers; and the partition has a brazing material
layer on at least one surface of a core material having two
surfaces.
11. A heat exchanger as set forth in claim 2, wherein the tubes
each have a brazing material layer on the outer peripheral surface
thereof.
12. A heat exchanger as set forth in claim 2, wherein the tubes
each comprise two metal plates joined in a tubular shape.
13. A heat exchanger as set forth in claim 12, wherein joint
portions of the two metal plates are provided along the length of
the tube.
14. A heat exchanger as set forth in claim 2, wherein the tubes
each comprise a single metal plate folded in a tubular shape.
15. A heat exchanger as set forth in claim 14, wherein the tubes
each have joint portions provided along the length of the tube.
16. A heat exchanger as set forth in claim 1, wherein: the first
member does not have the brazing material layer on the inner
peripheral surface thereof and has a brazing material layer on the
outer peripheral surface thereof, and the second member is
connected to an inner peripheral surface of the first member and
brazed to the first member.
17. A heat exchanger as set forth in claim 16, wherein the first
member and the second member of the header tank each have a
box-like shape with an opening formed in a combining direction to
each other.
18. A heat exchanger as set forth in claim 17, wherein the second
member has the brazing material layer thereon.
19. A heat exchanger as set forth in claim 16, wherein: the header
tank includes a pipe comprising the first member and the second
member, and lids for closing opposite open ends of the pipes; and
the lids are connected in the pipe.
20. A heat exchanger as set forth in claim 19, wherein the second
member includes the brazing material layer thereon.
21. A heat exchanger as set forth in claim 19, wherein the lids
each have a plate-like shape, and have a brazing material layer on
at least one surface thereof.
22. A heat exchanger as set forth in claim 16, further comprising a
partition fitted in each header tank for partitioning an interior
space of the header tank into a plurality of chambers, the
partition being connected to the inner peripheral surfaces of the
first and second members.
23. A heat exchanger as set forth in claim 22, wherein the
partition has a plate-like shape, and the brazing material layer on
at least one surface thereof.
24. A heat exchanger as set forth in claim 16, wherein an edge of
the first member is spaced from the outer peripheral surface of the
second member.
25. A heat exchanger comprising: heat transfer tubes provided as
heat transfer tubes; outer fins brazed to outer surfaces of the
tubes; and inner fins brazed inside the tubes; wherein each of the
tubes has joint portions, and does not have a brazing material
layer on an inner peripheral surface thereof but has a brazing
material layer on an outer peripheral surface thereof; and each of
the inner fins has brazing material layers on both surfaces of a
core material, and is brazed to the inner peripheral surface of the
tube, without contact with the joint portions of the tube.
26. A heat exchanger as set forth in claim 25, wherein the tubes
are each comprise a single bent metal plate in a tubular shape,
with a brazing material layer located at the outer peripheral
side.
27. A heat exchanger as set forth in claim 25, wherein the tubes
each comprise a plurality of metal plates in a tubular shape, with
a brazing material layers located at the outer peripheral side.
28. A heat exchanger as set forth in claim 25, further comprising:
header tanks to which open ends of the tubes are brazed; wherein
the tubes and the outer fins are arranged alternately.
29. A heat exchanger as set forth in claim 25, wherein the outer
fins each comprise a core material which does not have the brazing
material layers on either surface thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from the prior Japanese Patent Applications Nos.
2004-011689, 2004-015959 and 2004-021566 filed on Jan. 20, 2004,
Jan. 23, 2004 and Jan. 29, 2004, respectively; the entire contents
of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a heat exchanger for use in
automotive air-conditioning systems and the like.
[0004] 2. Description of the Related Art
[0005] A conventional heat exchanger includes flat tubes arranged
in multiple stages as heat transfer tubes, corrugated outer fins
each arranged between the adjacent multistage flat tubes, and a
pair of header tanks connected to opposite open ends of the flat
tubes for communication. A corrugated inner fin is inserted in each
tube.
[0006] The header tanks each include a pipe, lids closing opposite
open ends of the pipe, and a partition plate partitioning a passage
extending longitudinally through the pipe. The pipe has a plurality
of multistage tube insertion slots into which the tubes are
inserted.
[0007] In this heat exchanger, a refrigerant introduced into one of
the header tanks through a refrigerant inlet connector flows
through the tubes between the header tanks in a zigzag path, and
finally is discharged through a refrigerant outlet connector fixed
to either of the header tanks. During that time, the refrigerant
flowing through the heat exchanger exchanges heat with air passing
through spaces in the outer fins between the tubes. For example,
when the heat exchanger is used as a radiator or a condenser, the
refrigerant is cooled and the air is heated. When the heat
exchanger is used as an evaporator, the refrigerant is heated and
the air is cooled.
[0008] In the manufacturing method of the heat exchanger, with the
tubes and the outer fins arranged alternately, the tubes are
inserted into the tube insertion slots in the header tanks to form
a temporary assembly. Next, the temporary assembly is heated to a
predetermined temperature to melt brazing material on a surface of
each component, and then cooled. As a result, the components are
bonded (joined) to each other by the cooled brazing material so as
to form the heat exchanger.
[0009] In the above-described related art, the components
constituting the heat exchanger each have a brazing material layer
on a peripheral surface thereof. Therefore, during brazing, molten
brazing material flows all over the heat exchanger. Much of the
molten brazing material flows into joint surfaces by capillarity
flow. Generally, a core of the heat exchanger, in which the tubes
are joined to the outer fins, has a much greater total joint area
(total contact area) than the header tanks. Therefore, brazing
material of the header tanks flows out to the core of the heat
exchanger during brazing. As a result, the header tanks are short
of brazing material, so that (i) brazing between members
constituting the header tanks have reduced stability; (ii) brazing
between the header tanks and the tubes has reduced stability; and
(iii) brazing between the header tanks and piping connectors have
reduced stability.
[0010] In the above-described art, each tube may be formed by
bending a single metal plate into a tubular shape, or may be formed
by combining two metal plates in a tubular shape. The tube in
either form includes a metal plate joint (seam). With this tube
structure including a seam, during brazing, a molten brazing
material in a brazing material layer on the inner surface of the
tube and a molten brazing material in a brazing material layer on
the outer surface of the tube flow into or out of the tube through
the seam of the tube. At that time, the brazing material is
absorbed into one of the inner side and the outer side of the tube
which has a larger total joint area, and the other side of the tube
becomes short of brazing material. Generally, the total area of
inner joint surfaces of the tube (joint surfaces between the inner
peripheral surface of the tube and the inner fin) is larger than
the total area of outer joint surfaces of the tube (joint surfaces
between the outer peripheral surface of the tube and the outer
fins). Therefore, the outer joint surfaces of the tube (joint
surfaces between the outer peripheral surface of the tube and the
outer fins) tend to be short of brazing material.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to prevent molten
brazing material from flowing between a core of a heat exchanger
and header tanks during brazing. It is another object of the
present invention to prevent molten brazing material from flowing
from the inside of tubes to the outside of the tubes or from the
outside of the tubes to the inside of the tubes during brazing.
[0012] The inventors of the present invention have noted that a
portion of a tube having no brazing material layer thereon can
prevent flow of brazing material.
[0013] A heat exchanger according to one aspect of the present
invention comprises outer fins; a plurality of tubes arranged
alternately with the outer fins; and header tanks receiving open
ends of the tubes for communication with the tubes. The header
tanks each comprise a first member and a second member which are
combined with each other. The first member has tube insertion slots
into which the open ends of the tubes are inserted, while the
second member does not have tube insertion slots. The first member
is either a core material which does not have brazing material
layers on outer and inner peripheral surfaces thereof, or a core
material having a brazing material layer on an outer peripheral
surface thereof but not having a brazing material layer on an inner
peripheral surface thereof. The second member is brazed to the
outer or inner peripheral surface of the first member which does
not have brazing material layers thereon.
[0014] A heat exchanger according to another aspect of the present
invention comprises tubes; outer fins brazed to outer surfaces of
the tubes; and inner fins brazed inside the tubes. Each of the
tubes has a seam and does not have a brazing material layer on an
inner peripheral surface thereof but has a brazing material layer
on an outer peripheral surface thereof. Each of the inner fins has
brazing material layers on both surfaces of a core material, and is
brazed to the inner peripheral surface of the tube, avoiding
contact with the seam of the tube.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0015] FIG. 1 is an elevation view of an entire configuration of a
heat exchanger in a first embodiment of the present invention;
[0016] FIG. 2 is an exploded perspective view of a header tank and
surrounding parts of the heat exchanger;
[0017] FIG. 3 is a cross-sectional view of the exchanger header
tank at a portion where a tube insertion slot is located;
[0018] FIG. 4A is a cross-sectional view of the header tank at a
portion where a lid (or partition) is located; and FIG. 4B is a
cross-sectional view along line IVB-IVB in FIG. 4A;
[0019] FIG. 5 is a cross-sectional view of a tube in the heat
exchanger;
[0020] FIGS. 6A to 6C are explanatory diagrams illustrating a part
of a manufacturing process of the tube;
[0021] FIG. 7 is a cross-sectional view along line VII-VII in FIG.
1;
[0022] FIG. 8 is an exploded perspective view of a header tank and
surrounding parts of a heat exchanger in a second embodiment of the
present invention;
[0023] FIG. 9 is a cross-sectional view of the header tank in the
second embodiment at a portion where a lid (or partition) is
located;
[0024] FIG. 10 is a cross-sectional view of a header tank of a heat
exchanger in a third embodiment of the present invention;
[0025] FIG. 11 is a cross-sectional view of a header tank of a heat
exchanger in a fourth embodiment;
[0026] FIG. 12 is a cross-sectional view of a header tank of a heat
exchanger in a fifth embodiment;
[0027] FIG. 13 is a cross-sectional view of a header tank of a heat
exchanger in a sixth embodiment;
[0028] FIGS. 14A and 14B are perspective views of a header tank in
a modification; FIG. 14A illustrates the header tank before
combining; and FIG. 14B illustrates the header tank after
combining;
[0029] FIGS. 15A and 15B are perspective views of a header tank in
a modification; FIG. 15A illustrates the header tank before
combining; and FIG. 15B illustrates the header tank after
combining;
[0030] FIG. 16 is a cross-sectional view of a header tank of a heat
exchanger in a seventh embodiment at a portion where a tube
insertion slot is located;
[0031] FIG. 17A is a cross-sectional view of the header tank at a
portion where a lid (or partition) is located; and FIG. 17B is a
cross-sectional view along line XVIIB-XVIIB in FIG. 17A;
[0032] FIG. 18 is a cross-sectional view of a header tank of a heat
exchanger in an eighth embodiment at a portion where a tube
insertion slot is located;
[0033] FIG. 19A is a cross-sectional view of the header tank at a
portion where a lid (or partition) is located; and FIG. 19B is a
cross-sectional view along line XIXB-XIXB in FIG. 19A;
[0034] FIG. 20 is a cross-sectional view of a header tank of a heat
exchanger in a ninth embodiment at a portion where a tube insertion
slot is located;
[0035] FIG. 21 is a cross-sectional view of a header tank of a heat
exchanger in a tenth embodiment at a portion where a tube insertion
slot is located;
[0036] FIG. 22 is a cross-sectional view of a comparative example 1
to the seventh to tenth embodiments, at a portion of a header tank
where a tube insertion slot is located;
[0037] FIG. 23A is a cross-sectional view of a portion of the
header tank in FIG. 22 where a lid (or partition) is located; and
FIG. 23B is a cross-sectional view along line B-B in FIG. 23A;
[0038] FIG. 24 is a cross-sectional view of a comparative example 2
to the seventh to tenth embodiments, at a portion of a header tank
where a tube insertion slot is located;
[0039] FIG. 25A is a cross-sectional view of a portion of the
header tank in FIG. 24 where a lid (or partition) is located; and
FIG. 25B is a cross-sectional view along line XXVB-XXVB in FIG.
25A;
[0040] FIGS. 26A, 26B and 26C are diagrams illustrating
modifications of the tube in the first to tenth embodiments;
[0041] FIG. 27 is a diagram illustrating a modification of the tube
in the first to tenth embodiments;
[0042] FIG. 28 is a diagram illustrating a modification of the tube
in the first to tenth embodiments;
[0043] FIG. 29 is a diagram illustrating a modification of the tube
in the first to tenth embodiments;
[0044] FIG. 30 is an elevation view of an entire configuration of a
heat exchanger in an eleventh embodiment;
[0045] FIG. 31 is an exploded perspective view of a header tank and
surrounding parts of the heat exchanger;
[0046] FIG. 32 is a cross-sectional view of the heat exchanger
header tank at a portion where a tube insertion slot is
located;
[0047] FIG. 33A is a cross-sectional view of the header tank at a
portion where a lid (or partition) is located; and FIG. 33B is a
cross-sectional view along line XXXIIIB-XXXIIIB in FIG. 33A;
[0048] FIG. 34 is a cross-sectional view of a tube of the heat
exchanger;
[0049] FIGS. 35A, 35B and 35C are explanatory views illustrating a
part of a manufacturing process of the tube;
[0050] FIG. 36 is a vertical cross-sectional view of the heat
exchanger in FIG. 1;
[0051] FIG. 37 is a diagram illustrating a modification 1 of the
tube in the eleventh embodiment;
[0052] FIG. 38 is a diagram illustrating a modification 2 of the
tube in the eleventh embodiment;
[0053] FIG. 39 is a diagram illustrating a modification 3 of the
tube in the eleventh embodiment;
[0054] FIG. 40 is a diagram illustrating a modification 4 of the
tube in the eleventh embodiment;
[0055] FIG. 41 is a diagram illustrating a modification 5 of the
tube in the eleventh embodiment;
[0056] FIG. 42 is a diagram illustrating a modification 6 of the
tube in the eleventh embodiment;
[0057] FIG. 43 is a diagram illustrating a modification 7 of the
tube in the eleventh embodiment; and
[0058] FIG. 44 is a diagram illustrating a modification 8 of the
tube in the eleventh embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0059] An embodiment of the present invention will be described
below with reference to the drawings.
First Embodiment
[0060] FIGS. 1 to 7 illustrate a heat exchanger in a first
embodiment. The heat exchanger in this embodiment is used as a
condenser in which a circulating vapor phase refrigerant is
condensed while cooled.
[0061] Entire Configuration of the Heat Exchanger
[0062] As shown in FIG. 1, a heat exchanger 1 in the first
embodiment includes a plurality of outer fins 3, a plurality of
flat tubes 5 arranged alternately with the outer fins 3,
reinforcing side plates 11 disposed at the outermost ends in the
layering direction of the outer fins 3 and the tubes 5, and a pair
of header tanks 7 receiving opposite open ends of each tube 5 for
communication with the tubes 5.
[0063] A refrigerant inlet connector 15 is attached to one of the
header tanks 7 (left one in FIG. 1). A refrigerant outlet connector
17 is attached to the other header tank 7 (right one in FIG. 1). A
partition 27 is fitted in each header tank 7 for partitioning the
interior of the header tank 7 into a plurality of chambers.
[0064] When a refrigerant is introduced into the header tank 7
through the refrigerant inlet connector 15, the refrigerant flows
through the tubes 5 between the header tanks 7 in a zigzag path,
and finally is let out through the refrigerant outlet connector 17
of the header tank 7. During that time, the refrigerant flowing
through the tubes 5 exchanges heat with air passing outside the
tubes 5.
[0065] Header Tank
[0066] The configuration of the header tanks 7 will be mainly
described with reference to FIGS. 2 to 4.
[0067] Each header tank 7 includes a rectangular tube pipe 19, and
lids 25 closing opposite open ends 19a, 19a of the pipe 19. The
pipe 19 is a combination of a first member 21 and a second member
23 divided longitudinally. The partition 27 for partitioning the
interior space into a plurality of chambers is disposed in the
header tank 7.
[0068] Both of the first member 21 and the second member 23 are
formed in a C shape in a cross section. Specifically, the first
member 21 includes a flat base 29 orthogonal to the longitudinal
direction of the tube 5, and a pair of straight portions 31
projected from opposite sides of the base 29 in a generally
orthogonal direction, forming a substantially C-shape cross
section. The base 29 of the first member 21 has tube insertion
slots 33 into which open ends of the tubes 5 are inserted. Like the
first member 21, the second member 23 includes a flat base 35
orthogonal to the longitudinal direction of the tube 5, and a pair
of straight portions 37 projected from opposite sides of the base
35 in a generally orthogonal direction, forming a substantially
C-shape cross section. The base 35 of the second member 23 includes
an opening (not shown) into which a tubular portion 41 of the
refrigerant inlet connector 15 (or the refrigerant outlet connector
17) is inserted and fitted.
[0069] In this embodiment, the width dimension of the first member
21 (distance between the pair of straight portions 31) is set
larger than the width dimension of the second member 23 (distance
between the pair of straight portions 37). The first and second
members 21, 23 are brazed to each other with outer peripheral
surfaces of the straight portions 37 of the second member 23 fitted
to inner peripheral surfaces of the straight portions 31 of the
first member 21.
[0070] The base 35 of the second member 23 is provided with support
holes 43 for supporting projections 26a, 26a of the lids 25. Also,
the straight portions 37 of the second member 23 are provided with
support grooves 45 for supporting wings 26b, 26b of the lids 25.
The support holes 43 and the support grooves 45 in the second
member 23 allow the lids 25 to be positioned in place. In this
embodiment, the partition 27 has the same shape as that of the lids
25. The partition 27 also includes a projection 28a and wings 28b,
28b, and is positioned in place by a support hole (43) not shown
and support grooves (45) not shown formed in the second member
23.
[0071] The materials of the header tanks 7 will be mainly
described.
[0072] The material of the first member 21 is a core material 21a
having no brazing material layers on either surface. The C-shaped
first member 21 has no brazing material layers on its outer and
inner peripheral surfaces.
[0073] The material of the second member 23 is a core material 23a
integrally formed with a brazing material layer 23c on an entire
surface 23c on either side. The brazing material layer 23c is
located on the outer peripheral surface of the C-shaped second
member 23.
[0074] The material of each lid 25 is a core material 25a
integrally formed with brazing material layers 25b, 25c on both
surfaces entirely (FIG. 4B).
[0075] The material of the partition 27 is a core material 27a
integrally formed with brazing material layers 27b, 27c on both
surfaces entirely (FIG. 4B).
[0076] When the members of the header tank 7 (the first member 21,
the second member 23 and the lid 25) are assembled, a brazing
material layer is located between joint surfaces of the members.
Thus, brazing of the assembled members causes the members of the
header tank 7 to be fixed in a unit.
[0077] Although the lid 25 and the partition 27 have no brazing
material layers on their peripheries (surfaces to be brought into
contact with inner peripheral surfaces of the first and second
members 21, 23 constituting a pipe), the brazing material layers
25b, 25c on both surfaces of the lid 25 and the brazing material
layers 27b, 27c on both surfaces of the partition 27 are melted to
enter the peripheries by capillarity during brazing. Consequently,
the lid 25 and the partition 27 are brazed to the first and second
members 21, 23.
[0078] Tube
[0079] FIGS. 5 and 6A to 6C illustrate a tube 5. The tube 5 has a
tubular shape, and is brazed to the header tanks 7 with its
opposite ends inserted into the tube insertion slots 33 in the
header tanks 7. The tube 5 includes a corrugated inner fin 49.
[0080] With reference to FIGS. 6A to 6C, the manufacturing process
of the tube 5 will be described. First, a metal plate 5M of a
single elongated plate with a core material 5a integrally formed
with a brazing material layer 5c on either surface entirely is
prepared as a material 5M of the tube 5.
[0081] Then, as shown in FIG. 6A, opposite side portions of the
metal plate 5M of an elongated plate material are rolled inward to
form joint portions 47.
[0082] Then, the material 5M is folded into two along the
longitudinal center line so that the brazing material layer 5c is
located at the outer peripheral side of the tube 5. The joint
portions 47 at the edges of the fold are joined together to form a
tube. At that time, as shown in FIG. 5, the inner fin 49 is
inserted in the tube 5. The material of the inner fin 49 is a core
material 49a integrally formed with brazing material layers 49b,
49c on both surfaces as shown in FIG. 5.
[0083] Finally, when the heat exchanger 1 is brazed as a whole, the
joint portions 47 of the tube 5 are brazed to each other to be a
seam, and the inner surface of the tube 5 is brazed to the inner
fin 49. As a result, the tube 5 is completed. At the same time, the
outer surface of the tube 5 is brazed to the outer fins 3, and
outer surfaces at opposite ends of the tube 5 are brazed to the
inner peripheries of the tube insertion slots 33 in the header
tanks 7.
[0084] Outer Fin
[0085] The material of each outer fin 3 is a core material
integrally formed with brazing material layers on both
surfaces.
[0086] Manufacturing Process of the Heat Exchanger
[0087] The manufacturing process of the heat exchanger 1 in this
embodiment will be briefly described.
[0088] First, the outer fins 3, the tubes 5, the inner fins 49, the
members of the header tanks 7 (the first and second members 21 and
23 and the lids 25), the partitions 27, the connectors 15 and 17,
and the side plates 11 and 11, which are made from predetermined
materials, are prepared.
[0089] Then, these components are formed into their respective
predetermined shapes.
[0090] Then, all of the components are assembled and temporarily
fixed by a jig or the like to be a temporary assembly.
[0091] Then, the temporary assembly is heated in a furnace at a
predetermined temperature to braze the components together. That
is, brazing material layers of the components in the temporary
assembly are melted at a predetermined temperature and then cooled,
thereby to fix the components in a unit.
[0092] Functions
[0093] During brazing, the first member 21 having no brazing
material layers on its outer and inner peripheral surfaces
separates the brazing material layers 5c of the tubes 5 joined to
the first member 21 from other members than the tubes 5 (the second
member 23, the lids 25 and the partition 27) joined to the first
member 21. In other words, the first member 21 having no brazing
material layer separates the brazing material layers 5c of the
tubes 5 from brazing material layers of the header tank 7 (the
brazing material layer 23c of the second member 23, the brazing
material layers 25b, 25c of the lids 25 and the brazing material
layers 27b, 27c of the partition 27). Accordingly, during brazing,
no brazing material is exchanged between the heat exchanger core 1A
and the header tanks 7. As a result, the header tanks 7 are
prevented from being deprived of brazing material by the heat
exchanger core 1A having a large number of capillaries, and being
short of brazing material.
[0094] Effects
[0095] The effects of the first embodiment will be explained
below.
[0096] First, according to the first embodiment, the first member
21 having no brazing material layer separates the brazing material
layers 5c of the tubes 5 from brazing material layers of the header
tank 7 (the brazing material layer 23c of the second member 23, the
brazing material layers 25b, 25c of the lids 25 and the brazing
material layers 27b, 27c of the partition 27). Accordingly, the
header tank 7 is prevented from being deprived of brazing material
by the heat exchanger core 1A having a large number of capillaries,
and being short of brazing material. This results in good stability
in connection between a part (such as the connector 15, 17) joined
to the header tank 7 and the members (the first and second members
21, 23 and the lids 25) constituting the header tank 7. Also, since
brazing material of the header tank 7 does not flow to the heat
exchanger core 1A, unnecessary brazing material does not accumulate
on the tubes 5 and the outer fins 3 in the heat exchanger core 1A.
As a result, it never happens that accumulation of brazing material
reduces an airflow area between the tubes 5.
[0097] Second, according to the first embodiment, the material of
the second member 23 is the core material 23a integrally formed
with the brazing material layer 23c entirely on either of the inner
peripheral surface or the outer peripheral surface (the outer
peripheral surface in this embodiment) which includes a portion
joined to the first member 21. Thus, there is no need to previously
apply brazing materials X to joint portions of the first member 21
and the second member 23 as shown in FIG. 10 described below.
Consequently, the manufacturing process of the heat exchanger 1 is
simplified.
[0098] Third, according to the first embodiment, in the header tank
7 of a type including the pipe 19 and the lids 25 closing the
opposite open ends 19a, 19a of the pipe 19, the materials of the
lids 25 are the core materials 25a each integrally formed with the
brazing material layers 25b, 25c on both surfaces entirely. Thus,
there is no need to previously apply brazing material layers to
joint portions of the lids 25 and the first and second members 21,
23. Consequently, the manufacturing process of the heat exchanger 1
is simplified.
[0099] Fourth, according to the first embodiment, in the header
tank 7 of a type including the partition 27, the material of the
partition 27 is the core material 27a integrally formed with the
brazing material layers 27b, 27c on both surfaces entirely. Thus,
there is no need to previously apply brazing material layers to
joint portions of the partition 27 and the first and second members
21, 23. Consequently, the manufacturing process of the heat
exchanger 1 is simplified.
[0100] Fifth, according to the first embodiment, in the presented
type, the first member 21 is formed wider than the second member
23, and outer peripheral surfaces of the second member 23 are
fitted and brazed to inner peripheral surfaces of the first member
21. Since the material of the second member 23 is the core material
23a integrally formed with the brazing material layer 23c on its
entire outer surface, the first and second members 21 and 23 can be
joined without applying brazing materials X to joint surfaces of
the first and second members 21, 23 before brazing, unlike a third
embodiment in FIG. 10 to be described below. Consequently, the
manufacturing process of the heat exchanger 1 is simplified
(similar to the first effect). Further, since there is no need to
provide brazing material layers to the connector 15 (17), a liquid
tank and the like to be connected to the outer peripheral surface
of the second member 23, the manufacturing process of the heat
exchanger 1 is further simplified.
[0101] Sixth, according to the first embodiment, the material of
the tube 5 includes the brazing material layer 5c integrally formed
on the entire outer peripheral surface of the tube 5. Thus, there
is no need to apply brazing material to a joint region between the
tube 5 and the tube insertion slot 33. Also, there is no need to
apply brazing material to joint regions between the tube 5 and the
outer fins 3. Consequently, the manufacturing process of the heat
exchanger 1 is further simplified.
[0102] Also, in the structure presented in the first embodiment,
the tube 5 has no brazing material layer on its inner surface, and
the inner fin 49 has brazing material layers on both sides.
Therefore, there is no need to apply brazing material to joint
regions between the tube 5 and the inner fin 49 before brazing, and
the manufacturing process of the heat exchanger 1 is further
simplified.
[0103] Seventh, according to the heat exchanger 1 of this first
embodiment, the tube 5 is configured to have the joint portions 47.
In particular, the joint portions 47 are provided along the entire
length of the tube 5. This configuration causes brazing material of
the header tank 7 to be likely to be absorbed into the joint
portions 47 of the tube 5 during brazing. Thus, the brazing
material flow cutoff function of the first member 21 (a brazing
material flow cutoff portion S2) is more effective.
[0104] Eighth, in this first embodiment, in the tube 5 with the
joint portions 47, the inner fin 49 having the brazing material
layers 49b, 49c on both surfaces of the core material 49a is brazed
to the inner peripheral surface of the tube 5, avoiding contact
with the joint portions 47 of the tube 5. Therefore, brazing
material inside the tube 5 (the brazing material layers 49b, 49c on
both surfaces of the inner fin (49) is separated from brazing
material outside the tube 5 (the brazing material layer 5c on the
outer surface of the tube 5) by the tube inner peripheral surface
having no brazing material layer. That is, the inner peripheral
surface of the tube 5 has a brazing material flow cutoff portion S3
for preventing the flow of brazing material between the inside of
the tube 5 and the outside of the tube 5. Thus, during brazing,
brazing material inside the tube 5 is prevented from flowing out of
the tube 5 through a joint surface between the joint portions 47,
and brazing material outside the tube 5 is prevented from flowing
into the tube 5 through a joint surface between the joint portions
47. Thus, either the inside or the outside of the tube 5 never
becomes short of brazing material. In the first embodiment, the
total joint area inside the tube 5 (the total area of the joint
surfaces between the inner peripheral surface of the tube 5 and the
inner fin 49) is greater than the total joint area outside the tube
5 (the total area of the joint surfaces between the outer
peripheral surface of the tube 5 and the outer fins 3). Thus,
during brazing, the brazing material flow cutoff portion S3
prevents brazing material outside the tube 5 from flowing away into
the tube 5 to cause a shortage of brazing material at the outside
of the tube 5.
[0105] Other embodiments will be described below.
Second Embodiment
[0106] FIGS. 8 and 9 show a heat exchanger 1 in a second
embodiment. The heat exchanger 1 in the second embodiment is
different from the first embodiment in the structure of supporting
a lid 25 and a partition 27 in a header tank 7. In the second
embodiment, support holes 44 are additionally formed in a first
member 21 in the structure of the first embodiment. Projections 26c
and 28c to be supported by the support holes 44 are added to the
lid 25 and the partition 27, which is different from the first
embodiment.
[0107] According to the second embodiment, even with the structure
having the holes 44 formed in the first member 21, since a core
material 21a of the first member 21 has no brazing material layers
on its inner and outer peripheral surfaces, the first member 21
having no brazing material layers on the inner and outer peripheral
surfaces can have a brazing material flow cutoff function, as in
the first embodiment.
Third Embodiment
[0108] FIG. 10 shows a third embodiment. A header tank 100 in the
third embodiment in FIG. 10 is different from that in the first
embodiment in that a brazing material layer is not integrally
formed on the entire outer surface of a second member 102, and a
core material 102a is exposed to the entire second member 102. To
ensure a brazed joint between a first member 21 and the second
member 102, brazing materials X are applied to joint surfaces
between the first member 21 and the second member 102 before
brazing. At that time, the brazing materials X may be applied
either to the first member 21 or to the second member 102 before
brazing.
[0109] According to the third embodiment, as in the first
embodiment, the first member 21 having no brazing material layers
on its inner and outer peripheral surfaces can provide a brazing
material flow cutoff function.
Fourth Embodiment
[0110] FIG. 11 shows a fourth embodiment.
[0111] The fourth embodiment in FIG. 11 is different from the third
embodiment in that a header tank 110 has a second member 112 formed
wider than a first member 21, and outer peripheral surfaces of the
first member 21 is fitted and brazed to inner peripheral surfaces
of the second member 112. The second member 112 is constituted by a
core material, and brazing materials X are applied to joint
surfaces between the first member 21 and the second member 112
before brazing, as in the third embodiment. At that time, the
brazing materials X may be applied either to the first member 21 or
to the second member 112 before brazing.
[0112] According to the fourth embodiment, as in the first to third
embodiments, the first member 21 having no brazing material layers
on its inner and outer peripheral surfaces can provide a brazing
material flow cutoff function.
Fifth Embodiment
[0113] FIG. 12 shows a fifth embodiment. A header tank 120 in the
fifth embodiment is different from that in the fourth embodiment in
that a brazing material layer 121b is integrally formed on an
entire inner peripheral surface of a core material 120a of a second
member 121.
[0114] According to the fifth embodiment, unlike the fourth
embodiment, the first member 21 can be joined to the second member
121 without application of brazing materials X to joint surfaces
between the first member 21 and the second member 112 before
brazing. Thus, the manufacturing process of a heat exchanger 1 is
more simplified than in the fourth embodiment.
Sixth Embodiment
[0115] FIG. 13 shows a sixth embodiment. A header tank 130 in the
sixth embodiment is different from that in the fifth embodiment in
that the material of a second member 131 is a core material 131a
integrally formed with brazing material layers 131b, 131c on its
entire inner and outer peripheral surfaces.
[0116] The sixth embodiment eliminates the need for applying or
thermal spraying a brazing material to a connector 15 (17) to be
connected to the outer peripheral surface of the second member 131,
and thus the manufacturing process of a heat exchanger 1 is more
simplified, in addition to the effect in the fifth embodiment.
[0117] In the first to sixth embodiments, a first member 141 and a
second member 142 of a header tank 140 may be integrally formed
with a lid as shown in FIGS. 14A and 14B, for example, if a
material of the first member 141 is a core material with no brazing
material layers integrally formed on its inner and outer peripheral
surfaces. Alternatively, a first member 141 and a second member 152
of a header tank 150 may be integrally formed with a lid as shown
in FIGS. 15A and 15B, for example. That is, in the first to sixth
embodiments, the header tank 140 (header tank 150) may be of a type
in which it is longitudinally divided into the box-shaped first
member 141 (first member 151) and second member 142 (second member
152) which are combined in the longitudinal direction of the tubes,
each member having an opening formed in the combining
direction.
[0118] In short, according to the first to sixth embodiments, a
first member constituted by a core material having no brazing
materials on both surfaces separates a brazing material layer of a
tube from a brazing material layer of a header tank. That is, a
first member with no brazing material layer serves as a brazing
material flow cutoff portion. Consequently, the header tank is
prevented from being deprived of brazing material by a heat
exchanger core having a large number of capillaries, and being
short of brazing material. This results in a good stability in
connection between the header tank and a part (such as a connector)
joined to the header tank. Also, tubes and outer fins in the heat
exchanger core are prevented from having an accumulation of
unnecessary brazing material.
[0119] Seventh to tenth embodiments will be described. The seventh
to tenth embodiments are different from the first to sixth
embodiments in that a first member 161 is of a type having a
brazing material layer 161c on its outer surface.
Seventh Embodiment
[0120] A header tank 160 in the seventh embodiment is different
from that in the first embodiment in which the first member 21 has
no brazing material layers on its inner and outer peripheral
surfaces, in that, as shown in FIGS. 16 to 18, a first member 161
has a brazing material layer 161c on its outer surface, and in
other respects, is completely identical to that in the first
embodiment.
[0121] When members of the header tank 160 (the first member 161, a
second member 23, a lid 25) are assembled, a brazing material layer
is located between joint surfaces of the members. The assembled
members are brazed at a predetermined temperature, thereby to fix
the members of the header tank 160 in a unit.
[0122] In a heat exchanger in the seventh embodiment, the first and
second members 161 and 23 of the header tank 160 are brazed
together with the second member 23 fitted to the inner peripheral
surface of the first member 161. Thus, the inner peripheral surface
and edges of the first member 161 with no brazing material layers
(brazing material flow cutoff portions S2) separate a brazing
material layer 23c for joining the first and second members 161 and
23 from a brazing material layer of a tube 5. Therefore, during
brazing, the brazing material layer 23c for joining the first and
second members 161 and 23 is prevented from flowing away to the
tube 5 through the inner and outer peripheral surfaces of the first
member 161.
[0123] In the heat exchanger in the seventh embodiment, a lid 25 is
provided, and the lid 25 is fitted to the inner peripheral surface
of a pipe 19 consisting of the first member 161 and the second
member 23, with brazing material layers 25b, 25c of the lid 25 out
of contact with the brazing material layer 161c on the outer
peripheral surface of the first member 161. Thus, the brazing
material layers 25b, 25c of the lid 25 (brazing material layers
25b, 25c for joining the lid 25 to the first and second members 161
and 23) are separated from a brazing material layer 5c of a tube 5
by the inner peripheral surface with no brazing material layer and
edges S2 of the first member 161. Thus, the brazing material is
prevented from flowing away to the tube 5 during brazing.
Consequently, during brazing, brazing material in the brazing
material layers 23c, 25b and 25c for joining the lid 25 to the
inner peripheral surfaces of the first and second members 161 and
23 is prevented from flowing away from the inner and outer
peripheral surfaces of the first member 161 to the tube 5.
[0124] Thus, according to the seventh embodiment, during brazing,
the brazing material layer 23c for joining the first member 161 and
the second member 23 and the brazing material layers 25b, 25c and
23c for joining the lid 25 to the first and second members 161 and
23 are prevented from flowing away to the tubes 5.
[0125] Effects
[0126] The effects of the seventh embodiment will be summarized
below.
[0127] First, according to the seventh embodiment, the inner
peripheral surface and the edges S2 with no brazing material layers
of the first member 161 separates the brazing material layer 5c of
the tube 5 from brazing material layers of the header tank 160 (the
brazing material layer 23c of the second member 23 and the brazing
material layers 25b, 25c of the lid 25). Consequently, the header
tank 160 is prevented from being deprived of brazing material by a
heat exchanger core 1A having a large number of capillaries, and
being short of brazing material. This results in good stability in
connection between a part (such as a connector 15 or 17) joined to
the header tank 160 and members constituting the header tank 160
(the first and second members 161, 23 and the lid 25). Also, since
brazing material of the header tank 160 does not flow to the heat
exchanger core 1A, unnecessary brazing material does not accumulate
on tubes 5 and outer fins 3 in the heat exchanger core 1A. As a
result, accumulation of brazing material reducing an airflow area
between the tubes 5 never happens.
[0128] Second, like the lid 25, a partition 27 is fitted in the
pipe 19 comprised of the first and second members 161, 23, with its
brazing material layers 27b, 27c out of contact with the outer
peripheral surface of the first member 161 and tubes 5. Thus,
brazing material of the header tank 160 does not flow away to the
tubes 5 (heat exchanger core 1A) through the brazing material
layers 27b, 27c of the partition 27.
[0129] Third, in the heat exchanger 1 in the seventh embodiment,
each tube 5 is longitudinally provided with joint portions 47. With
this, a brazing material flow cutoff function of the first member
161 is more effective. If the first member 161 did not have the
brazing material flow cutoff function in the seventh embodiment,
brazing material of the header tank 160 would be further absorbed
into the joint portions 47 of the tube 5.
[0130] Fourth, according to the seventh embodiment, the second
member 23 has the brazing material layer 23c on its outer
peripheral surface. Thus, brazing material for joining the second
member 23 to the inner peripheral surface of the first member 161
is provided by the brazing material layer 23c on the outer
peripheral surface of the second member 23. This eliminates the
need for applying brazing materials (X) for joining a second member
(192) to the inner peripheral surface of a first member (161)
before brazing as in the tenth embodiment described below.
[0131] Fifth, according to the seventh embodiment, the lid 25 is in
a plate shape, and has the brazing material layer 25b, 25c on at
least one surface. Thus, brazing material for joining the lid 25 to
the inner peripheral surfaces of the first and second members 161
and 23 is provided by the brazing material layer 25b, 25c of the
lid 25. This eliminates the need for applying brazing material for
joining the lid 25 to the inner peripheral surfaces of the first
and second members 161 and 23 before brazing. In this embodiment,
the brazing material layer 23c on the outer peripheral surface of
the second member 23 flows over the brazing material layers 25b,
25c of the lid 25, thereby also acting as brazing material for
joining the inner peripheral surfaces of the first and second
members 161 and 23 and the lid 25.
[0132] Sixth, according to the seventh embodiment, the partition 27
is in a plate shape, and has the brazing material layer 27b, 27c on
at least one surface. This eliminates the need for applying brazing
material for joining the partition 27 to the inner peripheral
surfaces of the first and second members 161 and 23 before brazing.
In this embodiment, the brazing material layer 23c on the outer
peripheral surface of the second member 23 flows over the brazing
material layer 27b, 27c of the partition 27, thereby also acting as
brazing material for joining the partition 27 to the inner
peripheral surfaces of the first and second members 161 and 23.
Eighth Embodiment
[0133] FIGS. 18 and 19 show a header tank 170 of a heat exchanger
in an eighth embodiment. The header tank 170 in the eighth
embodiment has the same structure as that in the seventh embodiment
except that a second member 172 has brazing material layers 172c
and 172b on both inner and outer peripheral surfaces of a core
material 172a, respectively. Even with this structure in which the
second member 172 has the brazing material layer 172b on its inner
peripheral surface, the same effects as in the seventh embodiment
can be provided.
Ninth Embodiment
[0134] FIG. 20 shows a header tank 180 of a heat exchanger in a
ninth embodiment. The header tank 180 in the ninth embodiment is
different from that in the seventh embodiment in that a first
member 161 is provided with expanding portions 181 expanding in a
tapered cross-section shape at edges of a pair of straight portions
31, and edge portions S2 of the first member 161 are spaced from a
brazing material layer 23c on the outer peripheral surface of a
second member 23.
[0135] According to the ninth embodiment, in addition to the
effects in the seventh embodiment, even when the first member 161
is formed thinner, the edge portions S2 of the first member 161 can
reliably prevent a brazing material layer 161c on the outer
peripheral surface of the first member 161 from connecting to the
brazing material layer 23c on the outer peripheral surface of the
second member 23. This is also effective even if the first member
161 is not thin.
Tenth Embodiment
[0136] FIG. 21 shows a header tank 190 of a heat exchanger in a
tenth embodiment. The header tank 190 in the tenth embodiment is
different from those in the seventh to ninth embodiments in which
the second members 23, 172 have the brazing material layers 23c,
17c on the outer surfaces, in that a second member 192 is only
comprised of a core material 192 with no brazing material layer
thereon. Thus, before brazing of the header tank 190 in the tenth
embodiment, brazing materials X for joining a first member 161 and
the second member 192 are applied to the first member 161 or the
second member 192.
[0137] According to the tenth embodiment, similar functions and
effects to those in the seventh to ninth embodiments can be
provided. The manufacturing process of the heat exchanger 1 in the
seventh to ninth embodiments is simpler than in that in the tenth
embodiment because the brazing material layer 23c of the second
member 23 joins the first member 161 and the second member 23, thus
eliminating the need for separately applying brazing materials X
for joining the first member 161 and the second member 192 as in
the tenth embodiment.
[0138] Comparative examples to the seventh to tenth embodiments
will be described below. The comparative examples are intended to
clarify the structures and the functions/effects of the seventh to
tenth embodiments. Comparative examples 1 and 2 are not
conventional examples.
COMPARATIVE EXAMPLE 1
[0139] FIGS. 22, 23A and 23B show a comparative example 1. This
comparative example 1 is out of the scope of the present invention.
A header tank 200 of a heat exchanger in the comparative example 1
is different from those in the seventh to tenth embodiments in
which the first member 161 has the brazing material layer 161c only
on its outer peripheral surface, in that a first member 201 has a
brazing material layer 201b on its inner peripheral surface as well
as a brazing material layer 201c on its outer peripheral
surface.
[0140] In this comparative example 1, since the first member 201
has the brazing material layer 201b on its inner peripheral
surface, a brazing material layer 23c on the outer peripheral
surface of a second member 23 (brazing material for joining the
first member 201 and the second member 23) is in contact with the
brazing material layer 21b on the inner peripheral surface of the
first member 201 as shown in FIGS. 22 and 23A. The brazing material
layer 201b on the inner peripheral surface of the first member 21
is in contact with a brazing material layer on the outer peripheral
surface of a tube 5 projected into the pipe inner peripheral side
through a tube insertion slot 33 in the first member 21. Therefore,
during brazing, the brazing material layer 23c on the outer
peripheral surface of the second member 23 flows out to the brazing
material layer 5c on the outer peripheral surface of the tube 5
through the brazing material layer 201b on the inner peripheral
surface of the first member 21.
[0141] In the seventh to tenth embodiments, no brazing material
layer is provided to the inner peripheral surface of the first
member 161 which can be in contact with the brazing material layers
5c on the outer peripheral surfaces of the tubes 5. Thus, brazing
material of the header tanks 160, 170, 180 and 190 is prevented
from flowing out to the tubes 5.
COMPARATIVE EXAMPLE 2
[0142] FIGS. 24, 25A and 25B show a comparative example 2. This
comparative example 2 is also out of the scope of the present
invention. A header tank 300 of a heat exchanger in the comparative
example 2 includes a first member 21 provided with support holes
44, and a lid 25 and a partition 27 provided with projections 26c
and 28c supported by the support holes 44, in addition to the
components in the seventh to tenth embodiments.
[0143] In the comparative example 2, the projections 26c and 28c of
the lid 25 and the partition 27 are in contact with a brazing
material layer 301c on the outer peripheral surface of the first
member 21. Therefore, as shown in FIGS. 24, 25A and 25B, a brazing
material layer 23c on the outer peripheral surface of a second
member 23 (brazing material for joining the first member 21 and the
second member 23) flows out to tubes 5 through brazing material
layers 25b, 25c, 27b and 27c of the lid 25 and the partition 27,
through the projections 26c, 28c, through the brazing material
layer 301c on the outer peripheral surface of the first member 21,
and through brazing material layers on the outer peripheral
surfaces of the tubes 5. At the same time, brazing material in the
brazing material layers 25b, 25c, 27b and 27c of the lid 25 and the
partition 27 flows out to the tubes 5 in the same route.
[0144] In the seventh to tenth embodiments, when the lid 25 and/or
the partition 27 are provided, the lid 25 and/or the partition 27
are fitted in the header tank 160, 170, 180 or 190, with the
brazing material layers 25b, 25c, 27b and 27c of the lid 25 and/or
the partition 27 out of contact with the brazing material layer
161c on the outer peripheral surface of the first member 161. Thus,
brazing material of the header tank is prevented from flowing out
to the tubes 5. In the seventh to tenth embodiments, to support the
lid 25 and/or the partition 27 on the first member 161, support
portions can be in any shape such as a hole with a bottom or a
groove formed in the inner peripheral surface of the first member,
except for a hole extending from the inner peripheral surface to
the outer peripheral surface of the first member.
[0145] As described above, according to the seventh to tenth
embodiments, a header tank includes a first member and a second
member combined to each other; the first member includes tube
insertion slots, while the second member includes no tube insertion
slots; the first member has no brazing material layer on its inner
surface, while having a brazing material layer on its outer
surface; and the second member is fitted to the inner peripheral
surface of the first member. Therefore, brazing material of the
header tank (especially brazing material for joining the second
member to the first member) is prevented from flowing out to tubes
through the first member.
[0146] In any of the seventh to tenth embodiments, a joint surface
of a second member to a first member is an outer peripheral surface
of the second member. A joint surface of a second member to a first
member may be an inner peripheral surface of the second member, an
outer peripheral surface of the second member, or an edge surface
of the second member.
[0147] Also, in any of the seventh to tenth embodiments, a header
tank is configured to include a pipe 19 comprised of a first member
and a second member, and lids 25 at opposite ends of the pipe 19.
However, if a first member 141 and a second member 142 are
integrally formed with a lid as shown in FIG. 14, for example, the
same effects as in the seventh to tenth embodiments can be
obtained. That is, the header tank 140 may be of a type
longitudinally divided into the box-shaped first member 141 and
second member 142 which are combined in the longitudinal direction
of tubes 5, each member having an opening formed in the combining
direction.
[0148] In the structure in any of the first to tenth embodiments, a
partition is provided, but it is possible not to provide a
partition.
[0149] In the first to tenth embodiments, outer fins and side
plates may be configured to be in contact with a first member. When
outer fins, side plates and the like are in contact with a first
member, and the outer fins and the side plates are provided with
brazing material layers, brazing material of a header tank is out
of contact with the brazing material layers.
[0150] In the first to tenth embodiments, a tube with joint
portions is used. Alternatively, a tube with joint portions as in
"tube modification 1" or "tube modification 2" described below may
be used, or a tube with no joint portions as in "tube modification
3" described below may be used.
[0151] [Tube Modification 1]
[0152] Tubes in FIGS. 26A, 26B and 26C are different from the tube
in FIG. 5 in the shape of a joint. The tubes in FIGS. 26A, 26B and
26C are each of a type in which a single metal plate is folded in a
tubular shape, like the tube in FIG. 5.
[0153] A tube 50 in FIG. 26A is identical to the tube 5 in the
first embodiment in that an elongated plate-like material having a
brazing material layer 50 on an entire surface to constitute the
outer surface of a core material 50a is folded in a tubular shape,
and joint portions 51, 52 at opposite sides are brazed to each
other, but is different from the tube 5 in the first embodiment in
that one of the joint portions 51, 52 at the opposite sides of the
material (the upper one 51 in this embodiment) is formed longer
than the other one (the lower one 52 in this embodiment), and is
formed in a substantially C shape to enclose the other one. In
brazing, an inner surface of the joint portion 51 is in contact
with an outer surface of the joint portion 52 having a brazing
material layer, whereby the joint portions 51, 52 are brazed to
each other.
[0154] A tube 60 in FIG. 26B is identical to the tube 5 in FIG. 5
in that an elongated plate-like material having a brazing material
layer 60c on an entire surface to constitute the outer surface of a
core material 60a is folded in a tubular shape, and joint portions
61 at opposite sides are brazed to each other, but is different in
the shape of the joint portions 61.
[0155] A tube 70 in FIG. 26C is identical to the tube 5 in FIG. 5
in that an elongated plate-like material having a brazing material
layer 70c on an entire surface to constitute the outer surface of a
core material 70a is folded in a tubular shape, and joint portions
71 at opposite sides are brazed to each other, but is different
from the tube 5 in FIG. 5 in that the joint portions 71 are brazed
to each other at their inner surfaces with no brazing material
layers.
[0156] [Tube Modification 2]
[0157] FIG. 27 shows another modified tube. A tube 80 in FIG. 27 is
different from the tube 5 in FIG. 5 in that two metal plates 80A,
80B are used. The tube 80 is configured such that the two metal
plates 80A, 80B are joined in a tubular shape, and joint portions
81, 82 at opposite sides are brazed to each other. The tube 80 is
similar to the tube 5 in FIG. 5 in that it has the joint portions
81, 82 along its entire length.
[0158] [Tube Modification 3]
[0159] Tubes in the first to tenth embodiments include a seam, but
tubes may be formed seamlessly. A tube 90A in FIG. 28 and a tube
90B in FIG. 29 are longitudinally extruded tubes, and have no
seams. The tube 90A in FIG. 28 includes a separate inner fin 49;
and the tube 90B in FIG. 29 is integrated with an inner fin.
[0160] In the first to tenth embodiments, each outer fin 3 is
integrally formed with brazing material layers on both surfaces,
but may alternatively be formed integrally with a brazing material
layer only on one surface, or may have no brazing material layers
on both surfaces.
[0161] In the first to tenth embodiments, each tube 5 has the
brazing material layer 5c not on its inner surface but on its outer
surface, but alternatively, a brazing material layer may be
provided on the inner surface of the tube 5. If a brazing material
layer is provided on the inner surface of the tube 5, an inner fin
49 with no brazing material layers on either surface can be
used.
Eleventh Embodiment
[0162] An embodiment will be described which can prevent brazing
material from flowing from inner surfaces of tubes to outer
surfaces of the tubes or from outer surfaces of tubes to inner
surfaces of the tubes through seams of the tubes during
brazing.
[0163] FIGS. 30 to 36 illustrate a heat exchanger in an eleventh
embodiment. The heat exchanger in this embodiment is used as a
condenser in which a circulating vapor phase refrigerant is
condensed while cooled.
[0164] Entire Configuration of the Heat Exchanger
[0165] As shown in FIG. 30, a heat exchanger 501 in the eleventh
embodiment includes a plurality of outer fins 503, a plurality of
flat tubes 505 arranged alternately with the outer fins 503,
reinforcing side plates 511 disposed at the outermost ends in the
layering direction of the outer fins 503 and the tubes 505, and a
pair of header tanks 507 receiving opposite open ends of each tube
505 for communication with the tubes 505.
[0166] A refrigerant inlet connector 515 is attached to one of the
header tanks 507 (left one in FIG. 30). A refrigerant outlet
connector 517 is attached to the other header tank 507 (right one
in FIG. 30). A partition 527 is fitted in each header tank 507 for
partitioning the interior of the header tank 507 into a plurality
of chambers.
[0167] When a refrigerant is introduced into the header tank 507
through the refrigerant inlet connector 515, the refrigerant flows
through the tubes 505 between the header tanks 507 in a zigzag
path, and finally is let out through the refrigerant outlet
connector 517 of the header tank 507. During that time, the
refrigerant flowing through the tubes 505 exchanges heat with air
passing outside the tubes 505.
[0168] Header Tank Configuration
[0169] The header tanks 507 will be mainly described with reference
to FIGS. 31 to 33.
[0170] Each header tank 507 includes a rectangular tube pipe 519,
and lids 525 closing opposite open ends 519a, 519a of the pipe 519.
The pipe 519 is a combination of a first member 521 and a second
member 523 divided longitudinally. The partition 527 for
partitioning the interior space into a plurality of chambers is
disposed in the header tank 507.
[0171] Both of the first member 521 and the second member 523 are
formed in a C shape in cross section. Specifically, the first
member 521 includes a flat base 529 orthogonal to the longitudinal
direction of the tube 505, and a pair of straight portions 531
projected from opposite sides of the base 529 in a generally
orthogonal direction, forming a substantially C-shape cross
section. The base 529 of the first member 521 has tube insertion
slots 533 into which open ends of the tubes 505 are inserted. Like
the first member 521, the second member 523 includes a flat base
535 orthogonal to the longitudinal direction of the tube 505, and a
pair of straight portions 537 projected from opposite sides of the
base 535 in a generally orthogonal direction, forming a
substantially C-shape cross section. The base 535 of the second
member 523 includes an opening (not shown) into which a tubular
portion 541 of the refrigerant inlet connector 515 (or the
refrigerant outlet connector 517) is inserted and fitted.
[0172] In this embodiment, the width dimension of the first member
521 (distance between the pair of straight portions 531) is set
larger than the width dimension of the second member 523 (distance
between the pair of straight portions 537). The first and second
members 521, 523 are brazed to each other with outer peripheral
surfaces of the straight portions 537 of the second member 523
fitted to inner peripheral surfaces of the straight portions 531 of
the first member 521.
[0173] The base 535 of the second member 523 is provided with
support holes 543 for supporting projections 526a of the lids 525.
Also, the straight portions 537 of the second member 523 are
provided with support grooves 545 for supporting wings 526b, 526b
of the lids 525. The support holes 543, 543 and the support grooves
545 in the second member 523 allow the lids 525 to be positioned in
place. In this embodiment, the partition 527 has the same shape as
that of the lids 525. The partition 527 also includes a projection
528a and wings 528b, and is positioned in place by a support hole
not shown and support grooves not shown formed in the second member
523.
[0174] The materials of the header tanks 507 will be mainly
described.
[0175] The material of the first member 521 is a core material 521a
having a brazing material layer on either surface. The first member
521 formed in a predetermined shape (in a C shape) has a brazing
material layer 521c on an outer peripheral surface of the core
material 521a, but has no brazing material layer on an inner
peripheral surface.
[0176] The material of the second member 523 is a core material
523a integrally formed with a brazing material layer 523c on an
entire surface 523c on either surface. The second member 523 formed
in a predetermined shape (in a C shape) has the brazing material
layer 523c on the outer peripheral surface of the core material
523a.
[0177] The material of each lid 525 is a core material 525a
integrally formed with brazing material layers 525b, 525c on both
surfaces entirely (FIG. 33B).
[0178] The material of the partition 527 is a core material 527a
integrally formed with brazing material layers 527b, 527c on both
surfaces entirely (FIG. 33B).
[0179] When the members of the header tank 507 (the first member
521, the second member 523 and the rid 525) are assembled, a
brazing material layer is located between joint surfaces of the
members. Thus, brazing of the assembled members at a predetermined
temperature causes the members of the header tank 507 to be fixed
in a unit.
[0180] Although the rids 525 and the partition 527 have no brazing
material layers on their peripheries (surfaces to be brought into
contact with inner peripheral surfaces of the first and second
members 521, 523 constituting a pipe), the brazing material layers
525b, 525c on both surfaces of the rids 525 and the brazing
material layers 527b, 527c on both surfaces of the partition 527
are melted to enter the peripheries by capillarity during brazing.
Consequently, the lids 525 and the partition 527 are brazed to the
first and second members 521, 523.
[0181] Tube Configuration
[0182] FIGS. 34 and 35A to 35C illustrate a tube 505. The tube 505
has a tubular shape, and is brazed to the header tanks 507 with its
opposite ends inserted into the tube insertion slots 533 in the
header tanks 507. The tube 505 includes a corrugated inner fin
549.
[0183] With reference to FIGS. 35A to 35C, the manufacturing
process of the tube 505 will be described. First, a metal plate M
of a single elongated plate with a core material 505a integrally
formed with a brazing material layer 505c on either surface is
prepared as a material M of the tube 505.
[0184] Then, as shown in FIG. 35A, opposite side portions of the
metal plate M of an elongated plate material are rolled inward to
form joint portions 547.
[0185] Then, the material M is folded into two along the
longitudinal centerline so that the brazing material layer 505c is
located at the outer peripheral side of the tube 505. The joint
portions 547 at the edges of the fold are joined together to form a
tube. At that time, as shown in FIG. 34, the inner fin 549 is
inserted in the tube 505. The material of the inner fin 549 is a
core material 549a integrally formed with brazing material layers
549b, 549c on both surfaces as shown in FIG. 34.
[0186] Finally, when the heat exchanger 1 is brazed as a whole, the
joint portions 547 of the tube 505 are brazed to each other, and
the inner surface of the tube 505 is brazed to the inner fin 549.
As a result, the tube 505 is completed. At the same time, the outer
surface of the tube 505 is brazed to the outer fins 503, and outer
surfaces at opposite ends of the tube 505 are brazed to the inner
peripheries of the tube insertion slots 533 in the header tanks
507. Also, the members of the header tank are brazed to each
other.
[0187] In the eleventh embodiment, the inner fin 549 has the
brazing material layers 549b, 549c on both surfaces of the core
material 549a, and is brazed to the inner peripheral surface of the
tube 505, avoiding contact with the joint portions 547 of the tube
505.
[0188] Outer Fin
[0189] The material of the outer fin 503 is only a core material
with no brazing material.
[0190] Manufacturing Process of the Heat Exchanger
[0191] The process of manufacturing the heat exchanger 501 in this
embodiment will be briefly described.
[0192] First, the outer fins 503, the tubes 505, the inner fins 49,
the members of the header tanks 507 (the first and second members
521 and 523 and the rids 525), the partitions 527, the connectors
515 and 517, and the side plates 511 and 511, which are made from
predetermined materials, are prepared.
[0193] Then, these components are formed into their respective
predetermined shapes.
[0194] Then, all of the components are assembled and temporarily
fixed by a jig or the like to be a temporary assembly.
[0195] Then, the temporary assembly is sintered in a furnace at a
predetermined temperature to braze the components together. That
is, brazing material layers of the components in the temporary
assembly are melted at a predetermined temperature and then cooled,
thereby to fix the components in a unit.
[0196] Functions
[0197] According to the eleventh embodiment, no brazing material
layer is provided to the inner surface of the tube 505, while the
brazing material layers 549b, 594c are provided to both surfaces of
the inner fin 549 to join the tube 505 and the inner fin 549. The
inner fin 549 is brazed to the inner peripheral surface of the tube
505, avoiding contact with the joint portions 547. Therefore, as
shown in FIG. 34, a brazing material flow cutoff portion S3 for
separating brazing material inside the tube 505 (the brazing
material layers 549b, 549c on both surfaces of the inner fin 549)
from brazing material outside the tube 505 (the brazing material
layer 505c on the outer surface of the tube 5) is formed on the
inner surface of the tube 505 near the joint portions 547. The
brazing material flow cutoff portion S3 separates flow of the
brazing material inside the tube 505 from flow of the brazing
material outside the tube 505 during brazing.
[0198] Effects
[0199] The effects of the eleventh embodiment will be summarized
below.
[0200] First, according to the eleventh embodiment, as described
above, since the brazing material flow cutoff portion S3 is
provided for separating the brazing material inside the tube 505
(the brazing material layers 549b, 549c on the two sides of the
inner fin 549) from the brazing material outside the tube 505 (the
brazing material layer 505c on the outer surface of the tube 505)
so as to prevent flow of the brazing material between the inside of
the tube 505 and the outside of the tube 505, the brazing material
inside the tube 505 is prevented from flowing away to the outside
of the tube 505 through a joint surface between the joint portions
547, and the brazing material outside the tube 505 is prevented
from flowing away into the tube 505 through a joint surface between
the joint portions 547, during brazing.
[0201] Accordingly, no shortage of brazing material occurs inside
the tube 505 or outside the tube 505.
[0202] In the eleventh embodiment, the total joint area inside the
tube 505 (the total area of joint surfaces between the inner
peripheral surface of the tube 505 and the inner fin 549) is larger
than the total joint area outside the tube 505 (the total area of
joint surfaces between the outer peripheral surface of the tube 505
and the outer fins 503). Thus, the brazing material flow cutoff
portion S3 prevents brazing material outside the tube 505 from
flowing away into the tube 505 and causing shortage of brazing
material outside the tube 505.
[0203] Second, according to the eleventh embodiment, the tubes 505
and the outer fins 503 are arranged alternately, and the header
tanks 507 to which the open ends of the tubes 505 are brazed and
connected are provided. Thus, the brazing material flow cutoff
portions S3 act more effectively. Specifically, during brazing,
brazing material of each header tank 507 (brazing material in the
brazing material layer 521c on the outer surface of the first
member 521 in this embodiment) can be prevented from being absorbed
into the tubes 505 together with brazing material in the brazing
material layer 505c on the outer surface of the tube 505, and
running short. This is because, in the structure in which the tubes
505 are connected to the header tanks 507, during brazing, brazing
material of the header tanks 507 can also flow into the tubes 505
through joint surfaces between the joint portions 547 of the tubes
505 together with brazing material in the brazing material layers
505c on the outer surfaces of the tubes 505.
[0204] Third, according to the eleventh embodiment, each outer fin
503 is comprised of a core material having no brazing material
layer on either side, so that no exchange of brazing material is
made between the tubes 505. Therefore, even a structure in which
one of the tubes 505 improperly has a larger joint area than the
other tubes 505 can prevent brazing material from flowing in volume
to and accumulating on that particular tube 505.
[0205] [Tube Modifications]
[0206] In the eleventh embodiment, tubes may be modified as
described below as long as each tube separates brazing material
inside the tube (brazing material layers on both surfaces of an
inner fin) from brazing material outside the tube (a brazing
material layer on the outer surface of the tube) so as to prevent
flow of brazing material between the inside of the tube and the
outside of the tube. In the description below, identical or like
components are given like reference numerals, and those components
and their functions/effects will not be described.
[0207] [Tube Modification 1]
[0208] A tube 610 in a modification 1 shown in FIG. 37 is similar
to the tube 505 in the eleventh embodiment in FIG. 34 in that an
elongated plate-like material having a brazing material layer 610c
on an entire surface to be the outer surface of a core material
610a is folded longitudinally, and joint portions 611, 612 at
opposite sides are brazed to each other, but is different from the
tube 505 in the eleventh embodiment in the configurations of the
joint portions 611, 612. The tube 610 in the modification 1 also
includes a brazing material flow cutoff portion S3 for preventing
the flow of brazing material between the inside of the tube 610 and
the outside of the tube 610, and thus provides the same effects as
in the eleventh embodiment.
[0209] [Tube Modification 2]
[0210] A tube 620 in a modification 2 shown in FIG. 38 is also
different from the tube 505 in the eleventh embodiment in FIG. 34
in the configuration of joint portions 621. The tube 620 in the
modification 2 also includes a brazing material flow cutoff portion
S3 for preventing the flow of brazing material between the inside
of the tube 620 and the outside of the tube 620, and thus provides
the same effects as in the eleventh embodiment.
[0211] [Tube Modification 3]
[0212] A tube 630 in a modification 3 shown in FIG. 39 is also
different from the tube 505 in the eleventh embodiment in FIG. 34
in the configurations of joint portions 631, 632. The tube 630 in
the modification 3 also includes a brazing material flow cutoff
portion S3 for preventing the flow of brazing material between the
inside of the tube 630 and the outside of the tube 630, and thus
provides the same effects as in the eleventh embodiment. The tube
630 in the modification 3 is different from the tube 505 in the
eleventh embodiment in that a surface of the joint portion 632
having a brazing material layer 505c is joined to a surface of the
joint portion 631 having no brazing material layer.
[0213] [Tube Modification 4]
[0214] A tube 640 in a modification 4 shown in FIG. 40 is also
different from the tube 505 in the eleventh embodiment in FIG. 34
in the configurations of joint portions 641, 642. The tube 640 also
includes a brazing material flow cutoff portion S3 for preventing
the flow of brazing material between the inside of the tube 640 and
the outside of the tube 640, and thus provides the same effects as
in the eleventh embodiment. The tube 640 in the modification 4 is
different from the tube 505 in the eleventh embodiment and the
tubes 610, 620, 630 in the modifications 1 to 3 in that one of the
joint portions 641, 642 at opposite sides of the material (the
upper one 641 in this modification) is formed longer than the other
joint portion (the lower one 642 in this modification), and the
joint portion 641 is bent in a substantially C shape to enclose the
joint portion 642. In brazing, the joint portions 641, 642 are
brazed to each other with an inner surface of the joint portion 641
in contact with an outer surface of the joint portion 642 with a
brazing material layer.
[0215] [Tube Modification 5]
[0216] A tube 650 in a modification 5 shown in FIG. 41 is also
different from the tube 505 in the eleventh embodiment in FIG. 34
in the configuration of joint portions 651. The tube 650 in the
modification 5 also includes a brazing material flow cutoff portion
S3 for preventing the flow of brazing material between the inside
of the tube 650 and the outside of the tube 650, and thus provides
the same effects as in the eleventh embodiment.
[0217] The tube 650 in the modification 5 is different from the
tube 505 in the eleventh embodiment and modifications 1 to 4 in
that the joint portions 651 are brazed at their inner surfaces
having no brazing material layers. Generally, configuration with a
brazing material layer provided to at least one joint portion like
the tube 505 in FIG. 34 and the tubes 610 to 640 in the
modifications 1 to 4 will have better stability in a joint.
However, in the configuration of the tube 650 shown in the
modification 5, brazing material layers 650c on the outer surfaces
of the joint portions 651 will come around into the inner surfaces
of the joint portions 651 through the edges, thereby ensuring the
joint between the joint portions 651.
[0218] Tubes 660 to 680 in modifications 6 to 8 to be described
below are different from the tubes 610 to 640 in the modifications
1 to 5 in that they are formed by combining a plurality of (two in
those modifications) metal plates as materials.
[0219] [Tube Modification 6]
[0220] The tube 660 in the modification 6 shown in FIG. 42 is
different from the tube 610 in the modification 1 in FIG. 37 in
that two metal plates M1, M2 are used as materials, and joint
portions 661, 662 at opposite sides of the metal plates M1, M2 are
joined to one another, but otherwise is the same. Therefore, the
same effects as those of the tube 610 in the modification 1 in FIG.
37 can be provided.
[0221] [Tube Modification 7]
[0222] The tube 670 in the modification 7 shown in FIG. 43 is
different from the tube 620 in the modification 2 in FIG. 38 in
that two metal plates M1, M2 are used as materials, and joint
portions 671 at opposite sides of the metal plates M1, M2 are
joined to one another, but otherwise is the same. Therefore, the
same effects as those of the tube 620 in the modification 2 in FIG.
38 can be provided.
[0223] [Tube Modification 8]
[0224] The tube 680 in the modification 8 shown in FIG. 44 is
different from the tube 630 in the modification 3 in FIG. 39 in
that two metal plates M1, M2 are used as materials, and joint
portions 681, 682 at opposite sides of the metal plates M1, M2 are
joined to one another, but otherwise is the same. Therefore, the
same effects as those of the tube 630 in the modification 3 in FIG.
39 can be provided.
[0225] In summary, according to the eleventh embodiment, no brazing
material layer is provided to the inner surface of a tube and
brazing material layers are provided to both surfaces of an inner
fin to join the tube and the inner fin. Since the inner fin is
brazed to the inner peripheral surface of the tube, avoiding
contact with tube joint portions, brazing material inside the tube
(the brazing material layers on both sides of the inner fin) is
separated from brazing material outside the tube (the brazing
material layer on the outer surface of the tube). Therefore, flow
of molten brazing material during brazing is separated into flow of
brazing material inside the tube and flow of brazing material
outside the tube. As a result, during brazing, brazing material is
prevented from flowing away from the inside of the tube to the
outside of the tube and causing a shortage of brazing material
inside the tube, or brazing material is prevented from flowing away
from the outside of the tube to the inside of the tube and causing
a shortage of brazing material outside the tube.
[0226] The heat exchanger in the eleventh embodiment is a heat
exchanger in which tubes and header tanks are brazed together with
the tubes inserted into tube insertion slots in the header tanks.
Alternatively, it may be a heat exchanger in which tubular tank
portions are formed at longitudinal ends of tubes in such a manner
as to project in a layering direction of the tubes, and the tank
portions of the adjacent tubes in the layering direction are brazed
and connected to each other to form header tanks. The eleventh
embodiment may be a heat exchanger with no header tanks like a
serpentine-type one.
[0227] Although the invention has been described above by reference
to certain embodiments of the invention, the invention is not
limited to the embodiments described above. Modification and
variation of the embodiments can be made without departing from
scope of the appended claims. Therefore, the embodiments are only
for illustrative purpose and do not limit the invention.
* * * * *