U.S. patent application number 12/807488 was filed with the patent office on 2011-01-06 for heat exchanger with inserts having a stress absorber.
This patent application is currently assigned to DENSO CORPORATION. Invention is credited to Hirokazu Hirose, Hiroyuki Osakabe, Hajime Sugito, Takahiro Uno, Michiyasu Yamamoto.
Application Number | 20110000642 12/807488 |
Document ID | / |
Family ID | 46329486 |
Filed Date | 2011-01-06 |
United States Patent
Application |
20110000642 |
Kind Code |
A1 |
Hirose; Hirokazu ; et
al. |
January 6, 2011 |
Heat exchanger with inserts having a stress absorber
Abstract
A heat exchanger comprising: a core portion including a
plurality of tubes; a pair of header tanks communicating with the
tubes; and a pair of inserts arranged substantially parallel to the
length of the tubes, and in such a manner as to contact the core
portion at the ends of the core portion to transfer the heat from
the core portion, and having the ends thereof supported on the
header tanks; wherein a stress absorber to absorb the stress
generated along the length of each insert is formed in the insert;
wherein the stress absorber is formed over each insert from the
upstream side to the downstream side in the air flow; and wherein
the stress absorber is arranged in such a manner that the most
upstream end and the most downstream end thereof in the air flow
are not superposed, one on the other, along the direction of air
flow.
Inventors: |
Hirose; Hirokazu;
(Kariya-city, JP) ; Osakabe; Hiroyuki; (Chita-gun,
JP) ; Sugito; Hajime; (Nagoya-city, JP) ;
Yamamoto; Michiyasu; (Chiryu-city, JP) ; Uno;
Takahiro; (Kariya-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Assignee: |
DENSO CORPORATION
Kariya-city
JP
|
Family ID: |
46329486 |
Appl. No.: |
12/807488 |
Filed: |
September 7, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11974891 |
Oct 16, 2007 |
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12807488 |
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11484519 |
Jul 11, 2006 |
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11974891 |
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Current U.S.
Class: |
165/82 |
Current CPC
Class: |
F28D 2021/0094 20130101;
F28F 9/001 20130101; F28F 2265/26 20130101; F28D 1/05366 20130101;
F28F 9/0217 20130101 |
Class at
Publication: |
165/82 |
International
Class: |
F28F 7/00 20060101
F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 12, 2005 |
JP |
2005-202807 |
Jun 6, 2006 |
JP |
2006-157725 |
Oct 16, 2006 |
JP |
2006-281454 |
Claims
1. A heat exchanger comprising: a core portion including a
plurality of tubes with a heat medium flowing therein; a pair of
header tanks extending in a direction perpendicular to the length
of the tubes at the longitudinal ends of the tubes and
communicating with the tubes; and a pair of inserts arranged
substantially parallel to the length of the tubes, and in such a
manner as to contact the core portion at the ends of the core
portion to transfer the heat from the core portion, and having the
ends thereof supported on the header tanks; wherein a stress
absorber to absorb the stress generated along the length of each
insert is formed in the insert; the stress absorber is formed over
each insert from the upstream side to the downstream side in the
air flow; the stress absorber is arranged in such a manner that the
most upstream end and the most downstream end thereof in the air
flow are not superposed, one on the other, along the direction of
air flow; each insert includes a base portion having a surface
substantially parallel to the flat surfaces of the tubes and
extending substantially parallel to the length of the tubes, and a
pair of ribs are projected in a direction substantially
perpendicular to the base portion from the ends of the base portion
in the direction of air flow and are extended substantially
parallel to the length of the tubes; the portions of the ribs
corresponding to the most upstream end and the most downstream end
of the stress absorber are formed with notches, respectively; and
each stress absorber constitutes a base portion-side expansion of
the base portion having a substantially U-shaped cross section.
2. A heat exchanger according to claim 1, wherein the base
portion-side expansion is formed diagonally with respect to the
direction of air flow.
3. A heat exchanger according to claim 1, wherein the base
portion-side expansion is split into a plurality of parts in the
direction of air flow, and the plurality of the base portion-side
expansions are coupled to each other through slits formed in the
base portion.
4. A heat exchanger according to claim 3, wherein the plurality of
the base portion-side expansions are not arranged in alignment.
5. A heat exchanger according to claim 3, wherein the plurality of
the base portion-side expansions are tilted in different directions
with respect to the direction of air flow.
6. A heat exchanger according to claim 3, wherein the plurality of
the base portion-side expansions are arranged substantially
parallel to the direction of air flow in such a manner as not to be
superposed, one on another, in the direction of air flow.
7. A heat exchanger comprising: a core portion including a
plurality of tubes with a heat medium flowing therein; a pair of
header tanks extending in a direction perpendicular to the length
of the tubes at the longitudinal ends of the tubes and
communicating with the tubes; and a pair of inserts arranged
substantially parallel to the length of the tubes, and in such a
manner as to contact the core portion at the ends of the core
portion to transfer the heat from the core portion, and having the
ends thereof supported on the header tanks; wherein a stress
absorber to absorb the stress generated along the length of each
insert is formed in the insert; the stress absorber is formed over
each insert from the upstream side to the downstream side in the
air flow; the stress absorber is arranged in such a manner that the
most upstream end and the most downstream end thereof in the air
flow are not superposed, one on the other, along the direction of
air flow; the tubes each have a flat cross section in the direction
of air flow, and each insert includes a base portion having a
surface substantially parallel to the flat surface of the tubes and
extending in the direction substantially parallel to the length of
the tubes and a pair of ribs projected in the direction
substantially perpendicular to the base portion and extending in
the direction substantially parallel to the length of the tubes,
and the stress absorber is a notch cut in the base portion
diagonally to the direction of air flow.
8. A heat exchanger according to claim 7, wherein only one end of
the notch is open.
9. A heat exchanger according to claim 7, comprising a plurality of
notches.
10. A heat exchanger according to claim 9, wherein the plurality of
the notches are tilted in different directions with respect to the
direction of air flow.
11. A heat exchanger according to claim 7, comprising a plurality
of notches each having only one open end; the open ends of the
plurality of the notches are arranged on the base portion and
alternate between the upstream side and the downstream side in the
air flow.
12. A heat exchanger according to claim 7, wherein the notch
extends to the side ribs, the ends of the notch are arranged in the
plane of the pair of the side ribs, respectively, the insert is
formed with second notches substantially in parallel to the notch
from the outer end of the side ribs along the direction in which
the tubes are stacked, and the second notches each have only one
end thereof open.
13. A heat exchanger according to claim 7, wherein the notch is
formed in the base portion, the portion of each of the pair of the
ribs adjoining the corresponding notch is formed with a U-shaped
rib-side expansion in the direction of air flow, and each stress
absorber includes the corresponding rib-side expansion.
14. A heat exchanger comprising: a core portion including a
plurality of tubes with a heat medium flowing therein; a pair of
header tanks extending in a direction perpendicular to the length
of the tubes at the longitudinal ends of the tubes and
communicating with the tubes; and a pair of inserts arranged
substantially parallel to the length of the tubes, and in such a
manner as to contact the core portion at the ends of the core
portion to transfer the heat from the core portion, and having the
ends thereof supported on the header tanks; wherein a stress
absorber to absorb the stress generated along the length of each
insert is formed in the insert; the stress absorber is formed over
each insert from the upstream side to the downstream side in the
air flow; the stress absorber is arranged in such a manner that the
most upstream end and the most downstream end thereof in the air
flow are not superposed, one on the other, along the direction of
air flow; the insert is formed with protrusions projected outward
thereof along the direction in which the tubes are stacked, and the
protrusions are connected to a stress absorber.
15. A heat exchanger comprising: a core portion including a
plurality of tubes with a heat medium flowing therein; a pair of
header tanks extending in a direction perpendicular to the length
of the tubes at the longitudinal ends of the tubes and
communicating with the tubes; and a pair of inserts arranged
substantially parallel to the length of the tubes, and in such a
manner as to contact the core portion at the ends of the core
portion to transfer the heat from the core portion, and having the
ends thereof supported on the header tanks; wherein a stress
absorber to absorb the stress generated along the length of each
insert is formed in the insert; the stress absorber is formed over
each insert from the upstream side to the downstream side in the
air flow; the stress absorber is arranged in such a manner that the
most upstream end and the most downstream end thereof in the air
flow are not superposed, one on the other, along the direction of
air flow; the tubes have a flat section along the direction of air
flow, the insert includes a base portion having a surface
substantially parallel to the flat surface of the tubes and
extending in the direction substantially parallel to the length of
the tubes, the base portion has base portion-side ribs projected
outward along the direction in which the tubes are stacked and
extending in the direction substantially parallel to the length of
the insert, the stress absorber is a base portion-side expansion
having the section expanded substantially in the shape of U, and an
end of each of the base portion-side ribs is connected to the base
portion-side expansion.
16. A heat exchanger according to claim 15, wherein the insert has
a pair of side ribs projected in the direction substantially
perpendicular to the base portion from the ends of the base portion
along the direction of air flow, and the portions of the side ribs
corresponding to the most upstream end and the most downstream end
of the base portion-side expansion are formed with notches,
respectively.
17. A heat exchanger according to claim 15, wherein the base
portion-side ribs are formed on both sides, respectively, of the
base portion-side expansion.
18. A heat exchanger according to claim 17, wherein the base
portion-side ribs are arranged on one and the other sides,
respectively, of the center line (L) of the base portion across the
length of the insert in the air flow.
19. A heat exchanger according to claim 18, wherein the base
portion is formed with second base portion-side ribs projected
outward along the direction in which the tubes are stacked and
extending in the direction substantially parallel to the length of
the insert, the base portion-side ribs are formed on both sides,
respectively, of the base portion-side expansion and arranged on
one and the other sides, respectively, of the center line (L) of
the base portion across the length of the insert in the air flow,
and the second base portion-side ribs are arranged in opposed
relation to the base portion-side ribs, respectively, with respect
to the base portion-side expansion on each of one and the other
sides of the center line (L).
20. A heat exchanger according to claim 19, wherein the second base
portion-side each have an end thereof connected to the base
portion-side expansion.
21. A heat exchanger according to claim 15, wherein the base
portion-side ribs are formed on both sides, respectively, of the
base portion-side expansion and also on the center line (L) of the
base portion across the length of the insert in the air flow.
22. A heat exchanger according to claim 15, wherein the base
portion is formed with second base portion-side ribs projected
outward along the direction in which the tubes are stacked and
extending in the direction substantially parallel to the length of
the insert.
23. A heat exchanger according to claim 15, wherein the base
portion-side ribs are aligned on both sides, respectively, of the
base portion-side expansion, the base portion is formed with second
base portion-side ribs projected outward along the direction in
which the tubes are stacked and extending in the direction
substantially parallel to the length of the insert, and the second
base portion-side ribs are arranged on one and the other sides,
respectively, of the base portion-side expansion and connected to
the base portion-side ribs.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of Ser. No.
11/974,891, filed Oct. 16, 2007 which is a continuation-in-part
application of Ser. No. 11/484,519 filed on Jul. 11, 2006, claiming
priority of Japanese Patent Application Nos. 2006-281454 filed Oct.
16, 2006, 2006-157725 filed Jun. 6, 2006 and 2005-202807 filed Jul.
12, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a heat exchanger or, in
particular, to a heat exchanger effectively applicable to a
multiflow radiator for cooling the cooling water of the internal
combustion engine of an automotive vehicle.
[0004] 2. Description of the Related Art
[0005] The conventional multiflow radiator includes a core portion
having a plurality of tubes, a header tank communicating with the
plurality of the tubes and an insert arranged at the end of the
core portion for reinforcing the core portion. Also, the header
tank is configured of a core plate coupled with the tubes and a
tank body providing an internal space of the tank. The tubes and
the insert are inserted in the head tank and coupled to the core
plate. Under these conditions, the tubes are held by equal forces
by the insert through the fins.
[0006] In this radiator, the temperature of the cooling water
flowing in the tubes may undergo a change. The amount of thermal
expansion is different between the tubes directly affected by the
cooling water and the insert affected indirectly by the cooling
water. The difference in the amount of thermal expansion between
the tubes and the insert is liable to generate thermal stress due
to thermal distortion at the root (coupling) between the core plate
and the tubes adjacent to the insert. A repeated change in
temperature and hence a repeated change in thermal stress poses the
problem that the tubes in the neighborhood of the root may be
broken.
[0007] To obviate this problem, an anti-thermal distortion
structure has been proposed in which the thermal distortion is
absorbed by cutting the longitudinal central portion of the insert
(Japanese Unexamined Patent Publication No. 11-325783).
[0008] In another conventional anti-thermal distortion structure
that has been proposed, an expansion having a substantially
semicircular cross section is formed on the insert and adapted to
be deformed to absorb the thermal distortion (Japanese Unexamined
Patent Publication No. 11-237197).
[0009] In the anti-thermal distortion structure proposed in
Japanese Unexamined Patent Publication No. 11-325783, however, the
notch of the insert reduces the strength to hold the tubes. In the
case where the internal pressure in the tubes increases and the
tubes expand under the pressure of the cooling water, the notch of
the insert is locally deformed due to the pressure in the tubes. As
a result, the portion of the tube adjacent to the notch is deformed
by expansion and may break.
[0010] The anti-thermal distortion structure proposed by Japanese
Unexamined Patent Publication No. 11-237197 also poses a similar
problem to Japanese Unexamined Patent Publication No. 11-325783 due
to the fact that the tube holding strength of the expansion of the
insert is reduced.
SUMMARY OF THE INVENTION
[0011] In view of this fact, the object of the present invention is
to provide a heat exchanger in which the thermal distortion is
reduced while, at the same time, the pressure resistance
performance is secured.
[0012] In order to achieve the object described above, according to
a first aspect of the invention, there is provided a heat exchanger
comprising a core portion (4) including a plurality of tubes (2)
with a heat medium flowing therein, a pair of header tanks (5)
extending in a direction perpendicular to the length of the tubes
(2) at the longitudinal ends of the tubes (2) and communicating
with the tubes (2), and a pair of inserts (6) arranged
substantially parallel to the length of the tubes (2) in such a
manner as to contact the core portion (4) at the ends of the core
portion (4) and each having the ends thereof supported on the
corresponding header tank (5), wherein, in order to absorb the
stress generated along the length of each insert (6), a stress
absorber (74, 76, 77) is formed over the distance from the upstream
side to the downstream side of the insert (6) in the air flow in
such a manner that the most upstream end and the most downstream
end of the stress absorber (74, 76, 77) in the air flow are not
superposed, one on the other, along the direction of air flow.
[0013] By forming the stress absorber (74, 76, 77) in the insert
(7) as described above, the stress generated along the length of
the insert (7) can be absorbed. Also, in view of the fact that the
stress absorber (74, 76, 77) is formed with the most upstream and
the most downstream ends thereof in the air flow not superposed one
on the other along the direction of air flow, the stress absorber
(74, 76, 77), i.e. the portion of the insert (7) having a weak
force to hold the tubes (2) can be dispersed over the length of the
tubes (2). In the case where the internal pressure of the tubes (2)
increases, therefore, the insert (7) is prevented from being
deformed locally by the stress absorber (74, 76, 77). In this way,
the tubes (2) are prevented from being broken by expansion and
deformation. As a result, the thermal distortion can be reduced
while at the same time the pressure resistance performance is
secured.
[0014] Each tube (2) may have a flat cross section in the direction
of air flow, and the insert (7) may include a base portion (71)
having a surface substantially parallel to the flat surface (2a) of
the tube (2) and extending substantially in parallel to the length
of the tube (2), and ribs (72) projected in a direction
substantially perpendicular to the base portion (71) from the ends
of the base portion (71) in the direction of air flow and are
extended substantially parallel to the length of the tube (2),
wherein the portions of the ribs (72) corresponding to the most
upstream and the most downstream ends of the stress absorber are
formed with notches (73a, 73b), respectively, and the stress
absorber constitutes a base portion-side expansion (74) having a
substantially U-shaped cross section of the base portion (71).
[0015] A "substantial U shape" is a shape configured of two
substantially opposed parallel surfaces and a substantially arcuate
bottom surface connected to the two surfaces, in which the bottom
surface may include a horizontal portion. In other words, the cross
section may be substantially channel-shaped.
[0016] In this case, the base portion-side expansion (74) may be
tilted with respect to the direction of air flow.
[0017] According to a second aspect of the invention, there is
provided a heat exchanger wherein the base portion-side expansion
(74) is split into a plurality of portions in the direction of air
flow, which are connected to each other through slits (75) formed
in the cross section of the base portion (71).
[0018] As a result, the length of the base portion-side expansion
(74) along the direction of air flow can be reduced by the length
of the slits (75) in the direction of air flow, thereby improving
the moldability.
[0019] According to a third aspect of the invention, there is
provided a heat exchanger wherein a plurality of the base
portion-side expansions (74) are not aligned.
[0020] As a result, the distance between the notch (73a) on the
upstream side in the air flow and the notch (73b) on the downstream
side in the air flow can be increased without increasing the angle
that the base portion-side expansion (74) forms with the direction
of air flow. Thus, the pressure resistance performance can be
positively secured without deteriorating the moldability of the
base portion-side expansion (74).
[0021] According to a fourth aspect of the invention, there is
provided a heat exchanger wherein the plurality of the base
portion-side expansions (74) are tilted in different directions
from the direction of air flow.
[0022] This configuration can reduce the spring back at the time of
molding the plurality of the base portion-side expansions (74) and
thus improve the moldability.
[0023] According to a fifth aspect of the invention, there is
provided a heat exchanger wherein the plurality of the base
portion-side expansions (74) are arranged substantially parallel to
the direction of air flow in such a manner as not be superposed one
on another in the direction of air flow.
[0024] This configuration eliminates the need of tilting the base
portion-side expansions (74) from the direction of air flow and
therefore the moldability can be improved.
[0025] According to a sixth aspect of the invention, there is
provided a heat exchanger wherein each tube (2) has a flat cross
section in the direction of air flow and the insert (7) includes a
base portion (71) having a surface substantially parallel to the
flat surface (2a) of the tube (2) and extending in the direction
substantially parallel to the length of the tube (2) and ribs (72)
projected in the direction substantially perpendicular to the base
portion (71) and extending in the direction substantially parallel
to the length of the tube (2), and wherein the stress absorber is a
notch (76), cut in the base portion (71), diagonal to the direction
of air flow.
[0026] As a result, the stress absorber can be configured of only
the notch (76) formed in the insert (7), and therefore the pressure
resistance performance can be secured with a simple
configuration.
[0027] According to a seventh aspect of the invention, there is
provided a heat exchanger wherein only one end of the notch (76) is
open.
[0028] This configuration leaves one of the ribs (72) intact and
can avoid reducing a rigidity more than requires. As a result, the
force to hold the tubes (2) can be increased. Thus, the thermal
distortion can be reduced while, at the same time, positively
securing the pressure resistance performance.
[0029] Alternatively, the two ends of the notch (76) may be open or
connected to each other.
[0030] Further, a plurality of the notches (76) may be formed.
[0031] Furthermore, only one end of each of a plurality of notches
(76) may be open, and the open ends of the plurality of the notches
(76) may be arranged alternately between the upstream side and the
downstream side of the base portion (71) in the air flow.
[0032] In addition, the plurality of the notches (76) can be tilted
in directions different from the direction of air flow.
[0033] According to an eighth aspect of the invention, there is
provided a heat exchanger wherein the notch (76) is formed in the
base portion (71), the portion of the pair of the ribs (72)
adjoining the notch (76) is formed with a U-shaped rib-side
expansion (77) in the direction of air flow, and the stress
absorber includes the rib-side expansion (77).
[0034] By forming at least a notch (76) in the base portion (71)
and the rib-side expansions (77) on a pair of the ribs (72) in this
way, the stress generated along the length of each insert can be
positively absorbed.
[0035] According to a ninth aspect of the invention, the insert (7)
is formed with protrusions (78) projected outward along the
direction in which the tubes (2) are stacked and connected to a
stress absorber (74, 76, 77).
[0036] Upon application of a pressure (when the internal pressure
of the tubes (2) increases), the whole heat exchanger (1) is
deformed to expand along the direction in which the tubes (2) are
stacked, and upon vibration, the whole heat exchanger (1) is
deformed along both the length of the tubes (2) and the direction
in which the tubes (2) are stacked. The provision of the
protrusions (78) of the insert (7) projected outward along the
direction in which the tubes (2) are stacked, however, makes it
possible to increase the stiffness of the insert (7) along the
direction in which the tubes (2) are stacked. As a result, the
pressure resistance and the earthquake resistance are improved.
[0037] According to a tenth aspect of the invention, the tubes (2)
have a flat section along the direction of air flow, the insert (7)
includes a base portion (71) having a surface substantially
parallel to the flat surface of the tubes (2) and extending in the
direction substantially parallel to the length of the tubes (2),
the base portion (71) has base portion-side ribs (78) projected
outward along the direction in which the tubes (2) are stacked and
extending in the direction substantially parallel to the length of
the insert (7), the stress absorbing portion is a base portion-side
expansion (74) of the base portion (71) having the section expanded
substantially in the shape of U, and an end of each of the base
portion-side ribs (78) is connected to the base portion-side
expansion (74).
[0038] As described above, in view of the fact that the base
portion (71) of the insert (7) is formed with the base portion-side
ribs (78) projected outward along the direction in which the tubes
(2) are stacked, the stiffness of the insert (7) in the direction
along which the tubes (2) are stacked can be improved, thereby
improving the pressure resistance and the earthquake
resistance.
[0039] The stress, if generated along the length of the insert (7),
may be concentrated at the connector between the base portion (71)
of the insert (7) and the base portion-side expansion (74) and may
damage the connector. By connecting an end of each of the base
portion-side ribs (78) to the base portion-side expansion (74),
however, the stress is prevented from being concentrated on the
connector between the base portion (71) and the base portion-side
expansion (74).
[0040] According to an eleventh aspect of the invention, the insert
(7) has a pair of side ribs (72) projected in the direction
substantially perpendicular to the base portion (71) from the ends
of the base portion (71) along the direction of air flow, and the
parts of the side ribs (72) corresponding to the most upstream end
and the most downstream end of the base portion-side expansion (74)
are formed with notches (73a, 73b).
[0041] In view of the fact that the base portion (71) of the insert
(7) is formed with the base portion-side ribs (78) projected
outward along the direction in which the tubes (2) are stacked as
described above, the stiffness of the insert (7) along the
direction in which the tubes (2) are stacked can be improved. As a
result, even in the case where the height (length along the
direction in which the tubes (2) are stacked) of the side ribs (72)
is reduced, the stiffness of the insert (7), i.e. the strength of
the heat exchanger (1) can be secured. Even in the case where the
mounting space of the heat exchanger (1) is limited, therefore, the
height (length along the direction in which the tubes (2) are
stacked) of the core portion (4) can be increased by the amount
corresponding to the height reduction of the side ribs (72), and
therefore, the heat exchange performance is improved.
[0042] According to a twelfth aspect of the invention, the base
portion-side ribs (78) are arranged in a pair on both sides,
respectively, of the base portion-side expansion (74).
[0043] As a result, the base portion-side ribs (78) can be arranged
over a wide range along the length of the insert (7). Thus, the
stiffness of the insert (7) along the direction in which the tubes
(2) are stacked can be further increased for a further increased
pressure resistance and earthquake resistance.
[0044] In the twelfth aspect described above, the base portion-side
ribs (78) can be arranged on one and the other sides, respectively,
of the center line (L) of the base portion (71) along the direction
of air flow across the length of the insert (7). As a result, the
base portion-side ribs (78) can be arranged over a wide range of
the insert (7) in the direction of the air flow, and therefore, the
stiffness of the insert (7) along the direction in which the tubes
(2) are stacked can be further increased. Thus, the pressure
resistance and the earthquake resistance are further improved.
[0045] According to a thirteenth aspect of the invention, the base
portion (71) is formed with second base portion-side ribs (78a)
projected outward along the direction in which the tubes (2) are
stacked and extending substantially in parallel to the length of
the insert (7). This makes it possible to increase the stiffness of
the insert (7) along the direction in which the tubes (2) are
stacked for an improved pressure resistance and an improved
earthquake resistance.
[0046] According to a fourteenth aspect of the invention, the base
portion-side ribs (78) are arranged on one and the other sides,
respectively, of the center line (L) of the base portion (71) along
the direction of air flow across the length of the insert (7), the
base portion (71) has second base portion-side ribs (78a) projected
outward along the direction in which the tubes (2) are stacked and
extending substantially in parallel to the length of the insert
(7), the second base portion-side ribs (78a) are each arranged on
one of the two sides of the base portion-side expansion (74), i.e.
on one and the other sides, respectively, of the center line (L) of
the base portion (71) along the direction of air flow across the
length of the insert (7), and the second base portion-side ribs
(78a) are arranged in opposed relation to the base portion-side
ribs (78) with respect to the base portion-side expansion (74) on
one and the other sides, respectively, of the center line (L).
[0047] As a result, the stiffness of the insert (7) along the
direction in which the tubes (2) are stacked can be further
increased for an improved resistance to pressure and
earthquake.
[0048] In the fourteenth aspect described above, an end of each of
the second base portion-side ribs (78a) can be connected to the
base portion-side expansion (74). As a result, the stress
concentration on the connector between the base portion (71) and
the base portion-side expansion (74) can be more positively
prevented.
[0049] Also, the base portion-side ribs (78) are each arranged, on
one of the sides of the base portion-side expansion (74) and
aligned with each other, the base portion (71) is formed with
second base portion-side ribs (78a) projected along the direction
in which the tubes (2) are stacked and extending substantially in
parallel to the length of the insert (7), and the second base
portion-side ribs (78) are each arranged on one of the two sides of
the base portion-side expansion (74) and connected to the base
portion-side ribs (78), respectively.
[0050] According to a fifteenth aspect of the invention, a notch
(76) is extended to the side ribs (72), the ends of the notch (76)
are arranged in the planes of a pair of the side ribs (72), the
insert (7) is formed with second notches (79) substantially
parallel to the notch (76) from the outer end of the side ribs (72)
along the direction in which the tubes (2) are stacked, and only
one end of each of the second notches (79) is open.
[0051] As a result, the side ribs (72) of the insert (7) are not
fully cut, and therefore, the stiffness of the insert (7) is
prevented from being unnecessarily decreased, thereby making it
possible to positively increase both the pressure resistance and
the quake resistance.
[0052] Further, the notch (76) and the second notches (79) are
formed before press forming the insert (7), and therefore, the
formability is improved.
[0053] In the present specification, the expression "substantially
parallel" or "substantially in parallel" should be interpreted not
necessarily to mean "completely parallel" or "completely in
parallel" but may be interpreted to mean "almost parallel" or
"almost in parallel".
[0054] Incidentally, the reference numerals in parentheses, to
denote the above means, are intended to show the relationships
between the specific means which will be described later in an
embodiment of the invention.
[0055] The present invention may be more fully understood from the
description of preferred embodiments of the invention, as set forth
below, together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1 is a front view of the radiator 1 according to a
first embodiment.
[0057] FIG. 2A is a plan view showing the insert 7 according to the
first embodiment.
[0058] FIG. 2B is a front view of FIG. 2A.
[0059] FIG. 3A is a plan view showing the insert 7 according to a
second embodiment.
[0060] FIG. 3B is a front view of FIG. 3A.
[0061] FIG. 4A is a plan view showing the insert 7 according to a
third embodiment.
[0062] FIG. 4B is a front view of FIG. 4A.
[0063] FIG. 5A is a plan view showing the insert 7 according to a
fourth embodiment.
[0064] FIG. 5B is a front view of FIG. 5A.
[0065] FIG. 6A is a plan view showing the insert 7 according to a
fifth embodiment.
[0066] FIG. 6B is a front view of FIG. 6A.
[0067] FIG. 7A is a plan view showing the insert 7 according to a
sixth embodiment.
[0068] FIG. 7B is a front view of FIG. 7A.
[0069] FIG. 8A is a plan view showing the insert 7 according to a
seventh embodiment.
[0070] FIG. 8B is a front view of FIG. 8A.
[0071] FIG. 9A is a plan view showing the insert 7 according to an
eighth embodiment.
[0072] FIG. 9B is a front view of FIG. 9A.
[0073] FIG. 10A is a plan view showing the insert 7 according to a
ninth embodiment.
[0074] FIG. 10B is a front view of FIG. 10A.
[0075] FIG. 11A is a plan view showing the insert 7 according to a
tenth embodiment.
[0076] FIG. 11B is a front view of FIG. 11A.
[0077] FIG. 12 is a perspective view showing the insert 7 according
to the tenth embodiment.
[0078] FIG. 13 is a perspective view showing the insert 7 according
to an eleventh embodiment.
[0079] FIG. 14A is a view taken along arrow A in FIG. 13.
[0080] FIG. 14B is a sectional view taken along line B-B in FIG.
13.
[0081] FIG. 14C is a sectional view taken along line C-C in FIG.
13.
[0082] FIG. 15 is a perspective view showing the insert 7 according
to a twelfth embodiment.
[0083] FIG. 16A is a view taken along arrow D in FIG. 15.
[0084] FIG. 16B is a sectional view taken along line E-E in FIG.
15.
[0085] FIG. 16C is a sectional view taken along line F-F in FIG.
15.
[0086] FIG. 17 is a perspective view showing the insert 7 according
to a thirteenth embodiment.
[0087] FIG. 18 is a perspective view showing the insert 7 according
to a fourteenth embodiment.
[0088] FIG. 19 is a perspective view showing the insert 7 according
to a fifteenth embodiment.
[0089] FIG. 20 is a perspective view showing the insert 7 according
to a sixteenth embodiment.
[0090] FIG. 21 is a perspective view showing the insert 7 according
to a seventeenth embodiment.
[0091] FIG. 22 is a perspective view showing the insert 7 according
to an eighteenth embodiment.
[0092] FIG. 23 is a perspective view showing the insert 7 according
to a nineteenth embodiment.
[0093] FIG. 24 is a plan view schematically showing the insert 7
before bending the side ribs 72 according to the nineteenth
embodiment.
[0094] FIG. 25 is a perspective view showing the insert 7 according
to a twentieth embodiment.
[0095] FIG. 26 is a perspective view showing the insert 7 according
to a twenty-first embodiment.
[0096] FIG. 27 is a perspective view showing the insert 7 according
to a twenty-second embodiment.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0097] The first embodiment of the invention is explained below
with reference to FIGS. 1, 2. This embodiment is an application of
the heat exchanger according to this invention to the radiator 1
for exchanging heat between the air and the cooling water (heat
medium) that has cooled the vehicle engine. FIG. 1 is a front view
of the radiator 1 according to the first embodiment.
[0098] In FIG. 1, the cooling water flows in the tubes 2. Each tube
2 is flat so that the direction of air flow (direction
perpendicular to the page) coincides with the direction of the long
diameter, and a plurality of the tubes 2 are arranged in parallel
to each other in vertical direction in such a manner that the
longitudinal direction thereof coincides with the horizontal
direction.
[0099] The flat surfaces on the two sides of each tube 2 are
coupled with the corrugated fins 3, whereby the heat transfer area
with the air is increased to promote the heat exchange between the
cooling water and the air. The substantially rectangular heat
exchange unit including the tubes 2 and the fins 3 is hereinafter
referred to as the core portion 4.
[0100] The header tank 5 extends in the direction (vertical
direction in this embodiment) perpendicular to the length of the
tubes 2 at each longitudinal end (horizontal ends in this
embodiment) of the tubes 2 and communicates with a plurality of the
tubes 2. The header tank 5 includes a core plate 5a coupled with
the tubes 2 inserted therein and a tank body 5b providing the
internal space of the tank with the core plate 5a.
[0101] The header tank 5 includes a cooling water inlet 6a
connected to the cooling water outlet side of the engine (not
shown) and a cooling water outlet 6b connected to the cooling water
inlet side of the engine. Also, an insert 7 for reinforcing the
core portion 4 extends in the direction substantially parallel to
the length of the tubes 2 at each end of the core portion 4.
[0102] FIG. 2A is a plan view showing the insert 7 according to the
first embodiment, and FIG. 2B a front view of FIG. 2A. As shown in
FIGS. 2A, 2B, the insert 7 includes a base portion 71 having a
surface substantially parallel to the flat surface 2a of the tubes
2 and extending in the direction substantially in parallel to the
length of the tubes 2 and a pair of ribs 72 projected from the ends
of the base portion 71 along the air flow in the direction
(direction of tube stack) substantially perpendicular to the base
portion 71 and extending in a direction substantially parallel to
the length of the tubes 2.
[0103] The pair of the ribs 72 of the insert 7 are formed with
notches 73a, 73b, respectively, cut inward in the direction of the
tube stack from the outer end of the ribs 72 in the direction of
the tube stack. Also, the notch (hereinafter referred to the
upstream side notch 73a) formed in the rib 72 on the upstream side
in the air flow and the notch (hereinafter referred to as the
downstream side notch 73b) formed in the rib 72 on the downstream
side in the air flow are arranged in such a manner as not be
superposed, one on the other, in the direction of air flow.
[0104] The base portion 71 of the insert 7 is formed with a base
portion-side expansion 74. The base portion-side expansion 74 is
formed by expanding the cross section of the base portion 71
substantially into a U shape in the direction of the tube stack.
Also, the base portion-side expansion 74 is so configured to be
deformed to absorb the tension or compression stress generated
along the length of the insert 7.
[0105] As shown in FIG. 2A, the base portion-side expansion 74 is
formed to connect the upstream-side notch 73a and the
downstream-side notch 73b and is arranged diagonally to the
direction of air flow.
[0106] As explained above, the base portion 71 of the inset 6 is
formed with the base portion-side expansion 74 having a
substantially U-shaped cross section, and therefore the stress
generated along the length of the insert can be absorbed.
[0107] Also, by arranging the base portion-side expansion 74
diagonally to the direction of air flow, the stress absorber of the
insert 7, i.e. the portion of the insert 7 weak in the force to
hold the tube 2 can be dispersed over the length of the tube. As a
result, in the case where the internal pressure of the tube 2
increases, the base portion-side expansion 74 of the insert 7 can
be prevented from being locally deformed. Thus, the tube 2 is
prevented from being deformed by expansion thereby preventing the
breakage of the tube 2.
[0108] Thus, the thermal distortion is reduced and the pressure
resistance performance is secured at the same time.
[0109] Next, a second embodiment of the invention will be explained
with reference to FIGS. 3A, 3B. In FIGS. 3A, 3B, component parts
similar or identical to those of the first embodiment are
designated by the same reference numerals, respectively, and are
not described again. FIG. 3A is a plan view showing the insert 7
according to the second embodiment, and FIG. 3B a front view of
FIG. 3A.
[0110] As shown in FIGS. 3A, 3B, the base portion 71 of the insert
7 according to this embodiment is formed with a slit 75. According
to this embodiment, the slit 75 is arranged with the length thereof
substantially parallel to the length of the tubes 2.
[0111] Also, the base portion-side expansion 74 is split into two
parts in the direction of air flow. Of the two base portion-side
expansions 74 thus split, the one arranged upstream in the air flow
is called a first base portion-side expansion 74a and the one
arranged downstream in the air flow a second base portion-side
expansion 74b.
[0112] The two base portion-side expansions 74a, 74b are connected
to each other through the slit 75. Also, the two base portion-side
expansions 74a, 74b are arranged out of alignment. According to
this embodiment, the two base portion-side expansions 74a, 74b are
connected to the longitudinal ends, respectively, of the slit
75.
[0113] As a result, effects similar to those of the first
embodiment are produced.
[0114] Further, in view of the fact that the base portion-side
expansion 74 is split into two parts in the direction of air flow
and the two base portion-side expansions 74a, 74b thus split are
connected to each other through the slit 75, the length of the base
portion-side expansion 74 can be reduced by the length of the slit
75 in the direction of air flow. As a result, the moldability is
improved.
[0115] Also, in view of the fact that the two base portion-side
expansions 74a, 74b are not arranged in alignment, the distance
between the upstream-side notch 73a and the downstream-side notch
73b in the air flow can be increased without changing the angle of
the base portion-side expansion 74 with respect to the direction of
air flow. As a result, the pressure resistance performance can be
positively secured without reducing the moldability of the base
portion-side expansion 74.
[0116] Next, a third embodiment of the invention will be explained
with reference to FIGS. 4A, 4B. In FIGS. 4A, 4B, component parts
similar or identical to those of the second embodiment are
designated by the same reference numerals, respectively, and not
described again. FIG. 4A is a plan view showing the insert 7
according to the tenth embodiment, and FIG. 4B a front view of FIG.
4A.
[0117] As shown in FIG. 4A, the two base portion-side expansions
74a, 74b according to this embodiment are tilted in opposite
directions with respect to the direction of air flow.
[0118] More specifically, the end of the slit 75 connected with the
first base portion-side expansion 74a is arranged nearer to the
downstream-side notch 73b than to the upstream-side notch 73a in
the direction of the length of the tube. The end of the slit 75
connected with the second base portion-side expansion 74b, on the
other hand, is arranged farther from the upstream-side notch 73a
than from the downstream-side notch 73b in the direction along the
length of the tube.
[0119] As a result, effects similar to those of the second
embodiment are produced.
[0120] Further, in view of the fact that the two base portion-side
expansions 74a, 74b are tilted in opposite directions in the
direction of air flow, the spring back when molding the base
portion-side expansions 74a, 74b can be reduced for an improved
moldability.
[0121] Next, a fourth embodiment of the invention will be explained
with reference to FIGS. 5A, 5B. In FIGS. 5A, 5B, component parts
similar or identical to those of the second embodiment are
designated by the same reference numerals, respectively, and are
not described again. FIG. 5A is a plan view showing the insert 7
according to the fourth embodiment, and FIG. 5B is a front view of
FIG. 5A.
[0122] As shown in FIGS. 5A, 5B, the base portion 71 of the insert
7 according to this embodiment is formed with two slits 75.
According to this embodiment, the two slits 75 are arranged with
the length thereof substantially parallel to the length of the
tubes. Of the two slits 75, the one arranged on the upstream side
in the air flow is called a first slit 75a and the one arranged
downstream side in the air flow a second slit 75b.
[0123] The base portion-side expansion 74 is split into three parts
in the direction along the air flow. The resultant three base
portion-side expansions 74a to 74c are arranged substantially
parallel to the direction of air flow in such a manner as not to be
superposed, one on another, in the direction of air flow. Of the
three base portion-side expansions 74, the one arranged upstream in
the air flow is called a first base portion-side expansion unit
74a, the one arranged downstream in the air flow a second base
portion-side expansion 74b, and the one arranged between the first
base portion-side expansion 74a and the second base portion-side
expansion 74c a third base portion-side expansion 74c.
[0124] As shown in FIG. 5A, the three base portion-side expansions
74a to 74c are coupled to each other through the two slits 75a,
75b. More specifically, one end of the first slit 75a along the
tube length is connected to the first base portion-side expansion
74a, and the other end thereof to the third base portion-side
expansion 74c. The downstream end of the third base portion-side
expansion 74c along the direction of air flow is connected to one
end of the second slit 75b along the tube length, and the other end
thereof to the second base portion-side expansion 74b.
[0125] As a result, effects similar to those of the second
embodiment are produced.
[0126] Further, in view of the fact that the three base
portion-side expansions 74a to 74c are formed substantially in
parallel to the direction of air flow in such a manner as not to be
superposed, one on another, in the direction of air flow, the base
portion-side expansion 74 is not required to be tilted from the
direction of air flow, and therefore the moldability is
improved.
[0127] Next, a fifth embodiment of the invention will be explained
with reference to FIGS. 6A and 6B. In FIGS. 6A and 6B, the
component parts similar or identical to those of the first
embodiment are designated by the same reference numerals,
respectively, and not described any more. FIG. 6A is a plan view
showing the insert 7 according to the fifth embodiment, and FIG. 6B
is a front view of FIG. 6A.
[0128] As shown in FIGS. 6A and 6B, the insert 7 according to this
embodiment is formed with a notch 76. The notch 76 is formed by
cutting the base portion 71 diagonally from one end to the other
end in the direction of air flow in such a manner as to be tilted
from the direction of air flow. As a result, the upstream and
downstream ends of the notch 76 in the air flow are prevented from
being superposed, one on the other, in the direction of air
flow.
[0129] According to this embodiment, the notch 76 is formed
continuously from the upstream end to the downstream end of the
base portion 71 in the air flow. Also, the notch 76 is formed
continuously in the ribs 72. More specifically, the portion of each
rib 72 adjacent to the end of the notch 76 is notched substantially
in parallel to the direction along the tube stack. According to
this embodiment, therefore, the insert 7 is completely separated by
the notch 76.
[0130] As described above, by forming the notch 76 in the base
portion 71 of the insert 7, the stress generated along the length
of the insert 7 can be absorbed.
[0131] Also, in view of the fact that the notch 76 is arranged
diagonally with respect to the direction of air flow, the stress
absorber of the insert 7, i.e. the portion of the insert 7 having
little strength to hold the tube 2 can be dispersed along the tube
length. In the case where the internal pressure of the tube 2
increases, therefore, the tube 2 is prevented from being locally
deformed by expansion, thereby making it possible to prevent the
tube 2 being broken.
[0132] Thus, the thermal distortion can be reduced while, at the
same time, the pressure resistance performance is secured.
[0133] Further, in view of the fact that the stress generated along
the length of the insert 7 can be absorbed simply by forming the
notch 76 in the insert 7, the pressure resistance performance can
be secured with a simple configuration.
[0134] Next, a sixteenth embodiment of the invention will be
explained with reference to FIGS. 7A and 7B. In FIGS. 7A and 7B,
component parts similar or identical to those of the fifth
embodiment are designated by the same reference numerals,
respectively, and are not described again. FIG. 7A is a plan view
showing the insert 7 according to the sixth embodiment, and FIG. 7B
a front view of FIG. 7A.
[0135] As shown in FIGS. 7A and 7B, only one end (the upstream end
in the air flow in this embodiment) of the notch 76 according to
this embodiment is open. More specifically, one end of the notch 76
in the direction of air flow is connected to an end of the base
portion 71 in the direction of air flow, and the other end (the
downstream end in the air flow in this embodiment) of the notch 76
is located within the base portion 71. In other words, according to
this embodiment, the insert 7 is not completely separated by the
notch 76.
[0136] As described above, by opening only one end of this notch
76, one rib 72 is left intact and, therefore, an undesired rigidity
reduction can be avoided. As a result, the force to hold the tubes
2 can be increased, thereby reducing the thermal distortion while,
at the same time, positively securing the pressure resistance
performance.
[0137] Next, a seventh embodiment of the invention will be
explained with reference to FIGS. 8A and 8B. In FIGS. 8A and 8B,
component parts similar or identical to those of the sixth
embodiment are designated by the same reference numerals,
respectively, and are not described again. FIG. 8A is a plan view
showing the insert 7 according to the seventh embodiment, and FIG.
8B a front view of FIG. 8A.
[0138] As shown in FIGS. 8A and 8B, the base portion 71 of the
insert 7 according to this embodiment is formed with three parallel
notches 76. The three notches 76 are all formed by cutting the base
portion 71, from the upstream end toward the downstream end thereof
in the air flow.
[0139] By forming the three notches 76 in the base portion 71 in
this way, the stress generated in the direction along the length of
the insert 7 can be positively absorbed. Thus, the thermal
distortion can be reduced while, at the same time, the pressure
resistance performance is secured.
[0140] Next, an eighth embodiment of the invention will be
explained with reference to FIGS. 9A and 9B. In FIGS. 9A and 9B,
component parts similar or identical to those of the seventh
embodiment are designated by the same reference numerals,
respectively, and are not described again. FIG. 9A is a plan view
showing the insert 7 according to the eighth embodiment, and FIG.
9B is a front view of FIG. 9A.
[0141] As shown in FIGS. 9A and 9B, the base portion 71 of the
insert 7 is formed with three parallel notches 76. According to
this embodiment, the notch 76a arranged outside and along the tube
length is formed by cutting the base portion 71, from the upstream
end toward the downstream end in the air flow. The notch 76b
arranged inside in the direction of tube stack, on the other hand,
is formed by cutting the base portion 71 from the downstream end to
the upstream end in the air flow.
[0142] As a result, effects similar to those of the seventh
embodiment described above are achieved.
[0143] Next, a ninth embodiment of the invention will be explained
with reference to FIGS. 10A and 10B. In FIGS. 10A and 10B,
component parts similar or identical to those of the seventh
embodiment are designated by the same reference numerals,
respectively, and are not described again. FIG. 10A is a plan view
showing the insert 7 according to the ninth embodiment, and FIG.
10B a front view of FIG. 10A.
[0144] As shown in FIGS. 10A and 10B, the base portion 71 of the
insert 7 according to this embodiment is formed with four notches
76. Of the four notches 76, two (hereinafter referred to as first
notch portions 76c) are formed by cutting the base portion 71, from
the upstream end toward the downstream end in the air flow. The two
other notches (hereinafter referred to as a second notch portion
76d), other than the first notch portion 76c, on the other hand,
are formed by cutting the base portion 71, from the downstream end
toward the upstream end in the air flow.
[0145] The two notches of the first notch portion 76c are arranged
substantially parallel to each other. The two notches of the second
notch portion 76d, on the other hand, are tilted in the opposite
direction to the first notch portion 76c in the direction of air
flow. Also, the two notches of the second notch portion 76d are
arranged substantially in parallel to each other.
[0146] As a result, effects similar to those of the seventh
embodiment described above are produced.
[0147] Next, a tenth embodiment of the invention will be explained
with reference to FIGS. 11A, 11B. In FIGS. 11A, 11B, component
parts similar or identical to those of the fifth embodiment are
designated by the same reference numerals, respectively, and are
not described again. FIG. 11A is a plan view showing the insert 7
according to the tenth embodiment, and FIG. 11B a front view of
FIG. 11A. FIG. 12 is a perspective view showing the insert 7
according to the tenth embodiment.
[0148] As shown in FIGS. 11A, 11B and 12, the ends of the notch 76
(hereinafter referred to as the rectangular portions 760) in the
direction of air flow according to this embodiment are
substantially rectangular and larger than the other parts of the
notch 76. Also, the portion of each rib 72 adjacent to the
corresponding rectangular portion 760 is formed with a rib-side
expansion 77 of the rib 72 having a substantially U-shaped cross
section. According to this embodiment, the rib-side expansions 77
are formed inward of the insert 7 in the direction of air flow.
[0149] As described above, by forming the notch 76 in the base
portion 71 and the rib-side expansions 77 of the pair of the ribs
72, the stress generated in the direction along the length of the
insert can be positively absorbed.
[0150] Also, the diagonal arrangement of the notch 76, with respect
to the direction of air flow, makes it possible to disperse the
stress absorber of the insert 7, i.e. the portion of the insert 7
having a weak force to hold the tubes 2, over the length of the
tube. As a result, in the case where the internal pressure of the
tube 2 increases, the tube 2 is prevented from being locally
expanded and deformed, thereby making it possible to prevent the
tube 2 from being broken.
[0151] As a result, thermal distortion is positively reduced while
at the same time the pressure resistance performance is
secured.
[0152] Next, the eleventh embodiment of the invention is explained
with reference to FIGS. 13 and 14. The component parts similar to
those of the first embodiment described above are designated by the
same reference numerals, respectively, and not explained again.
[0153] FIG. 13 is a perspective view showing the insert 7 according
to the eleventh embodiment, FIG. 14A is a view taken along arrow A
in FIG. 13, FIG. 14B is a sectional view taken in line B-B in FIG.
13, and FIG. 14C is a sectional view taken in line C-C in FIG.
13.
[0154] As shown in FIGS. 13 and 14A to 14C, the base portion 71 of
the insert 7 is formed with base portion-side ribs (protrusions) 78
projected outward along the direction in which the tubes 2 are
stacked and extending substantially parallel to the length of the
insert 7. The base portion-side ribs 78 have an end thereof
connected to the base portion-side expansion 74. According to this
embodiment, the other end of each of the base portion-side ribs 78
is arranged at the longitudinal ends of the base portion 71.
[0155] The base portion-side ribs 78 are each arranged on each side
of the base portion-side expansion 74, or specifically, one each on
each of the sides of the base portion-side expansion 74 on the base
portion 71. The two base portion-side ribs 78 are arranged on one
and the other sides, respectively, of the center line L across the
length of the insert 7 (hereinafter referred to simply as the
center line) of the base portion 71 in the direction of air flow.
According to this embodiment, the two base portion-side ribs 78 are
connected to one and the other ends, respectively, of the base
portion-side expansion 74 in the direction of air flow.
[0156] Also, as shown in FIGS. 14B and 14C, the base portion-side
ribs 78 are formed to have a substantially semicircular
section.
[0157] Upon application of pressure thereto (when the internal
pressure of the tubes 2 rises), the whole radiator 1 is deformed to
expand along the direction in which the tubes 2 are stacked, and
upon vehicle vibration, the whole radiator 1 is deformed both along
the length of the tubes 2 and along the direction in which the
tubes 2 are stacked. By forming the base portion-side expansion 74
with the section thereof expanded substantially in the shape of U
on the base portion 71 of the insert 7, on the other hand, the
stress generated along the length of the insert 7 can be absorbed.
Further, according to this embodiment, the base portion-side ribs
78 projected outward along the direction in which the tubes 2 are
stacked are formed on the base portion 71 of the insert 7, so that
the stiffness of the insert 7 along the direction in which the
tubes 2 are stacked can be improved. As a result, the resistance to
both the pressure and the earthquake is improved.
[0158] The stress, if generated along the length of the insert 7,
is concentrated at the connector between the base portion 71 of the
insert 7 and the base portion-side expansion 74 and may break the
connector. By connecting one end of each of the base portion-side
ribs 78 to the base portion-side expansion 74, on the other hand,
the stress concentration at the connector between the base portion
71 and the base portion-side expansion 74 is prevented.
[0159] Also, the stiffness of the insert 7 along the direction in
which the tubes 2 are stacked can be secured by the base
portion-side ribs 78, and therefore, the height of the side ribs 72
(the length along the direction in which the tubes 2 are stacked)
can be reduced. Therefore, even in the case where the mounting
space of the radiator 1 is limited, the core portion 4 can be
enlarged by the amount corresponding to the height reduction of the
side ribs 72, thereby making it possible to improve the heat
exchange performance.
[0160] Also, one each of the base portion-side ribs 78 is arranged
on each side of the base portion-side expansion 74, and therefore,
the base portion-side ribs 78 can be arranged over a wide range in
the longitudinal direction of the insert 7, thereby making it
possible to further increase the stiffness of the insert 7 along
the direction in which the tubes 2 are stacked. Thus, the pressure
resistance and the quake resistance are improved.
[0161] Further, the base portion-side ribs 78 are arranged on one
and the other sides of the center line L of the base portion 71,
and therefore, the base portion-side ribs 78 can be arranged over a
wide range on the insert 7 in the direction of air flow. Thus, the
stiffness of the insert 7 along the direction in which the tubes 2
are stacked can be further increased. Thus, the pressure resistance
and the quake resistance can be improved.
[0162] Next, the twelfth embodiment of the invention is explained
with reference to FIGS. 15 and 16. The twelfth embodiment, compared
with the eleventh embodiment described above, is different in that
the side ribs 72 are omitted. The component parts similar to those
of the eleventh embodiment are designated by the same reference
numerals, respectively, and not explained.
[0163] FIG. 15 is a perspective view showing the insert 7 according
to the twelfth embodiment. FIG. 16A is a view taken along arrow in
FIG. 15, FIG. 16B is a sectional view taken in line E-E in FIG. 15,
and FIG. 16C is a sectional view taken in line F-F in FIG. 15. As
shown in FIGS. 15 and 16A to 16C, the insert 7 has only the base
portion 71.
[0164] As described above, by providing the base portion 71 of the
insert 7 with the base portion-side ribs 78 projected outward along
the direction in which the tubes 2 are stacked, the stiffness of
the insert 7 along the direction in which the tubes 2 are stacked
can be increased, and therefore, the side ribs can be omitted. As a
result, even in the case where the mounting space of the radiator 1
is limited, the core portion 4 can be increased in size by the
amount corresponding to the side ribs removed. Thus, heat exchange
performance is improved.
[0165] Next, the thirteenth embodiment of the invention is
explained with reference to FIG. 17. The thirteenth embodiment is
different from the twelfth embodiment in that the base portion-side
ribs 78 are differently arranged. The component parts similar to
those of the twelfth embodiment are designated by the same
reference numerals, respectively, and not explained again.
[0166] FIG. 17 is a perspective view showing the insert 7 according
to the thirteenth embodiment. As shown in FIG. 17, the two base
portion-side ribs 78 arranged on the two sides, respectively, of
the base portion-side expansion 74 of the base portion 71 are
connected to the base portion-side expansion 74 in the neighborhood
of the center of air flow. As a result, the effects similar to
those of the twelfth embodiment are obtained.
[0167] Next, the fourteenth embodiment of the invention is
explained with reference to FIG. 18. The fourteenth embodiment is
different from the eleventh embodiment in that the base
portion-side ribs 78 are differently arranged. The component parts
similar to those of the eleventh embodiment are designated by the
same reference numerals, respectively, and not explained more.
[0168] FIG. 18 is a perspective view showing the insert 7 according
to the fourteenth embodiment. As shown in FIG. 18, the two base
portion-side ribs 78 arranged on both sides of the base
portion-side expansion 74 of the base portion 71 are arranged on
the center line L of the base portion 71. Also, the two base
portion-side ribs 78 are connected to the central part of the base
portion-side expansion 74 in the direction of air flow. As a
result, similar effects to those of the eleventh embodiment are
obtained.
[0169] Next, the fifteenth embodiment of the invention is explained
with reference to FIG. 19. The fifteenth embodiment is different
from the twelfth embodiment in the provision of second base
portion-side ribs 78a. The component parts similar to those of the
twelfth embodiment are designated by the same reference numerals,
respectively, and not described any more.
[0170] FIG. 19 is a perspective view showing the insert 7 according
to the fifteenth embodiment. As shown in FIG. 19, the part of the
base portion 71 not having the base portion-side ribs 78 is formed
with the second base portion-side ribs 78a projected outward along
the direction in which the tubes 2 are stacked and extending in the
direction substantially parallel to the length of the insert 7.
According to this embodiment, the second base portion-side ribs 78a
have a substantially semicircular section.
[0171] Also, each of the second base portion-side ribs 78a is
arranged on one of the two sides of the base portion-side expansion
74. The two second base portion-side ribs 78a are arranged on one
and the other sides, respectively, of the center line L of the base
portion 71. Also, on one and the other sides of the center line L
of the base portion 71, the second base portion-side ribs 78a are
arranged in opposed relation with the base portion-side ribs 78,
respectively, with respect to the base portion-side expansion
74.
[0172] As explained above, the part of the base portion 71 not
having the base portion-side ribs 78 is formed with the second base
portion-side ribs 78a, thereby making it possible to further
increase the stiffness of the insert 7 along the direction in which
the tubes 2 are stacked. As a result, the pressure resistance and
the quake resistance are further improved.
[0173] Also, by arranging each of the second base portion-side ribs
78 on each of the two sides of the base portion-side expansion 74,
the second base portion-side ribs 78a can be arranged over a wide
range along the length of the insert 7. Further, the two second
base portion-side ribs 78a are arranged on one and the other sides
of the center line L of the base portion 71, so that the second
base portion-side ribs 78 can be arranged over a wide range of the
insert 7 in the direction of air flow. Further, on one and the
other sides of the center line L, the second base portion-side ribs
78a are arranged in opposed relation with the base portion-side
ribs 78, respectively, with respect to the base portion-side
expansion 74, and therefore, the base portion-side ribs 78 or the
second base portion-side ribs 78a can be arranged substantially
over the entire area of the base portion 71. As a result, the
stiffness of the insert 7 along the direction in which the tubes 2
are stacked can be further increased, thereby improving the
pressure resistance and the quake resistance further.
[0174] Next, the sixteenth embodiment of the invention is explained
with reference to FIG. 20. The sixteenth embodiment is different
from the fifteenth embodiment in that an end of each of the second
base portion-side ribs 78a is connected to the base portion-side
expansion 74. The component parts similar to those of the fifteenth
embodiment are designated by the same reference numerals,
respectively, and not explained any more.
[0175] FIG. 20 is a perspective view showing the insert 7 according
to the sixteenth embodiment. As shown in FIG. 20, the second base
portion-side ribs 78a each have an end thereof connected to the
base portion-side expansion 74. According to this embodiment, the
base portion-side ribs 78 and the second base portion-side ribs 78a
are aligned with each other on each of one and the other sides of
the center line L. Also, the two second base portion-side ribs 78a
are connected one and the other ends, respectively, of the base
portion-side expansion 74 in the direction of air flow.
[0176] As explained above, an end of each of the second base
portion-side ribs 78a is connected to the base portion-side
expansion 74, and therefore, the stress concentration at the
connector between the base portion 71 and the base portion-side
expansion 74 is positively prevented.
[0177] Next, the seventeenth embodiment of the invention is
explained with reference to FIG. 21. The component parts similar to
those of the sixteenth embodiment are designated by the same
reference numerals, respectively, and not explained again.
[0178] FIG. 21 is a perspective view showing the insert 7 according
to the seventeenth embodiment of the invention. As shown in FIG.
21, the base portion-side ribs 78 and the second base portion-side
ribs 78a are connected to other than the ends of the base
portion-side expansion 74 in the direction of air flow.
[0179] More specifically, the base portion-side ribs 78 and the
second base portion-side ribs 78a arranged upstream of the center
line L of the base portion 71 in the air flow are connected to the
part of the base portion-side expansion 74 upstream of the center
line L in the air flow. Also, the base portion-side ribs 78 and the
second base portion-side ribs 78a arranged downstream of the center
line L of the base portion 71 in the air flow are connected to the
part of the base portion-side expansion 74 downstream of the center
line L in the air flow. As a result, the effects similar to those
of the sixteenth embodiment are achieved.
[0180] Next, the eighteenth embodiment of the invention is
explained with reference to FIG. 22. The eighteenth embodiment is
different from the fourteenth embodiment in the provision of the
second base portion-side ribs 78a. The component parts similar to
those of the fourteenth embodiment are designated by the same
reference numerals, respectively, and not explained again.
[0181] FIG. 22 is a plan view showing the insert 7 according to the
eighteenth embodiment of the invention. As shown in FIG. 22, the
part of the base portion 71 lacking the base portion-side ribs 78
is formed with the second portion-side ribs 78a projected outward
along the direction in which the tubes 2 are stacked and extending
in the direction substantially parallel to the length of the insert
7. The second base portion-side ribs 78a are each arranged on one
of the two sides of the base portion-side expansion 74. The two
base portion-side ribs 78a are arranged on one and the other sides,
respectively, of the center line L of the base portion 71.
[0182] According to this embodiment, the two base portion-side ribs
78a are each connected to the other end (the side not connected
with the base portion-side expansion 74) of the two base
portion-side ribs 78, respectively. More specifically, the second
base portion-side ribs 78a arranged upstream of the center line L
of the base portion 71 in the air flow are connected to the surface
of the base portion-side ribs 78 upstream in the air flow. Also,
the second base portion-side ribs 78a arranged downstream of the
center line L of the base portion 71 in the air flow are connected
to the surface of the base portion-side ribs 78a downstream in the
air flow.
[0183] As explained above, the part of the base portion 71 not
having the base portion-side ribs 78 has the second base
portion-side ribs 78a, respectively, and therefore, the stiffness
of the insert 7 along the direction in which the tubes 2 are
stacked is further improved. As a result, the pressure resistance
and the quake resistance are improved.
[0184] Next, the nineteenth embodiment of the invention is
explained with reference to FIGS. 23, 24. The component parts
similar to those of the 5th embodiment are designated by the same
reference numerals, respectively, and not explained again.
[0185] FIG. 23 is a perspective view showing the insert 7 according
to the nineteenth embodiment of the invention. As shown in FIG. 23,
a first notch 76 is formed from one end to the other of the base
portion 71 of the insert 7 at an angle to the direction of air
flow. The first notch 76 is also formed continuously to the side
ribs 72. Specifically, the tilt angle .theta..sub.1 of the part of
the first notch 76 formed on the base portion 71 to the air flow is
equal to the tilt angle .theta..sub.2 of the part of the first
notch 76 formed on the side ribs 72 to the direction in which the
tubes 2 are stacked. Also, the ends of the first notch 76 are
arranged in the plane of a pair of the side ribs 72, respectively,
and therefore, the side ribs 72 are not completely divided.
[0186] The pair of the side ribs 72 are formed with a second notch
79 inward from the outer end thereof along the direction in which
the tubes 2 are stacked. The second notches 79 each have one end
thereof open, and according to this embodiment, the other end (the
end not open) of each of the second notches 79 is arranged in the
plane of the side ribs 72. Also, the second notches 79 are each
formed substantially in parallel to the first notch 76.
[0187] According to this embodiment, the second notch 79 formed on
the side rib 72 downstream in the air flow (hereinafter referred to
as the downstream-side second notch 79b) along the length of the
insert 7, as viewed from the first notch 76, is formed on the same
side as the second notch 79 on the side rib 72 upstream in the air
flow (hereinafter referred to as the upstream-side second notch
79a). Specifically, the downstream-side second notch 79b is
arranged on the same side as the upstream-side second notch 79a
with respect to the first notch 76 in the direction along the
length of the insert 7.
[0188] FIG. 24 is a plan view schematically showing the insert 7
before bending the side ribs 72 according to the nineteenth
embodiment. As shown in FIG. 24, according to this embodiment, the
first and second notches 76, 79 are formed at the same time that
the insert 7 is press formed. The ends of the insert 7 with the
first and second notches 76, 79 formed thereon along the short side
thereof are bent in the same direction thereby to form the side
ribs 72, thereby completing the insert 7 shown in FIG. 23.
[0189] As explained above, the first notch 76 is extended to the
side ribs 72, and the ends of the first notch 76 are arranged in
the plane of the pair of the side ribs 72, respectively. Thus, the
side ribs 72 are not completely divided, and therefore, the
unnecessary decrease of the stiffness of the insert 7 can be
avoided. As a result, the pressure resistance and the quake
resistance can be positively secured.
[0190] In view of the fact that the ends of the first notch 76 are
arranged in the plane of the side rib pair 72, respectively, the
stress generated along the length of the insert 7 is difficult to
absorb. Therefore, the second notches 79 substantially in parallel
to the first notch 76 are formed from the outer end of the side
ribs 72 along the direction in which the tubes 2 are stacked. In
this way, the stress along the length of the insert 7 can be easily
absorbed. As a result, the thermal distortion can be further
reduced.
[0191] Further, the first and second notches 76, 79 may be formed
before press forming the insert 7. Thus, the process of forming the
notches by cutting the insert 7 is not required after forming the
core 4 by brazing the insert 7 together with the tubes 2 and the
fins 3. As a result, the formability is improved.
[0192] Next, the twentieth embodiment of the invention is explained
with reference to FIG. 25. The twentieth embodiment is different
from the nineteenth embodiment in that the other end of each of the
second notches 79 of the insert 7 is arranged at a different
position. The component parts similar to those of the nineteenth
embodiment are designated by the same reference numerals,
respectively, and not explained more.
[0193] FIG. 25 is a perspective view showing the insert 7 according
to the twentieth embodiment. As shown in FIG. 25, the other end
(the end not open) of each second notch 79 is arranged in the plane
of the base portion 71 of the insert 7. As a result, the effects
similar to those of the nineteenth embodiment are achieved.
[0194] Next, the twenty-first embodiment of the invention is
explained with reference to FIG. 26. The twenty-first embodiment is
different from the twentieth embodiment in that the second notches
79 are arranged at different positions. The component parts similar
to those of the twentieth embodiment are designated by the same
reference numerals, respectively, and not explained more.
[0195] FIG. 26 is a perspective view showing the insert 7 according
to the twenty-first embodiment. As shown in FIG. 26, the
downstream-side second notch 79b is arranged on the side of the
first notch 76 far from the upstream-side second notch 79a along
the length of the insert 7. Specifically, the downstream-side
second notch 79b is arranged on the other side of the first notch
76 far from the upstream-side notch 79a in the longitudinal
direction of the insert 7. As a result, the effects similar to
those of the twentieth embodiment are achieved.
[0196] Next, the twenty-second embodiment of the invention is
explained with reference to FIG. 27. The twenty-second embodiment
is different from the twenty-first embodiment in the provision of
third notches 80. The component parts similar to those of the
twenty-first embodiment are designated by the same reference
numerals, respectively, and not explained more.
[0197] FIG. 27 is a perspective view showing the insert 7 according
to the twenty-second embodiment. As shown in FIG. 27, a pair of
side ribs 72 are each formed with the third notch 80 inward from
the outer end along the direction in which the tubes 2 are stacked.
The third notches 80 each have only one end thereof open, and
according to this embodiment, the other end (the end not opened) of
each of the third notches 80 is arranged in the plane of the side
ribs 72. Also, the third notches 80 are formed substantially in
parallel to the first and second notches 76, 79.
[0198] According to this embodiment, the third notch 80 formed on
the side rib 72 upstream in the air flow (hereinafter referred to
as the upstream-side third notch 80a) is arranged on the side of
the upstream-side second notch 79a far from the first notch 76.
Also, the third notch 80 formed on the side rib 72 downstream in
the air flow (hereinafter referred to as the downstream-side third
notch 80b) is arranged on the side of the first notch 76 far from
the downstream-side second notch 79b. The third notches 80 are also
formed at the same time that the insert 7 is press formed.
[0199] As explained above, the insert 7 is formed with the second
and third notches 79, 80 substantially in parallel to the first
notch 76 from the outer end of the side ribs 72 along the direction
in which the tubes 2 are stacked. Thus, the stress generated along
the length of the insert 7 can be absorbed more easily. As a
result, the thermal distortion can be further reduced.
[0200] Finally, other embodiments will be described. Although the
embodiments described above are an application of the invention to
the cross-flow radiator in which the cooling water flows in
horizontal direction. Nevertheless, this invention is applicable
also to the down-flow radiator in which the cooling water flows
vertically.
[0201] Also, this invention is not limited to the embodiments
described above in which the stress absorber, of the insert 7, is
not in contact with the core portion 4. As an alternative, the
stress absorber of the insert 7 may be in contact with the core
portion 4.
[0202] Further, unlike in the seventh and eighth embodiments
described above in which three notches 76 are formed in the base
portion 71, two or four or more notches 76 may be formed.
[0203] In similar fashion, in spite of the fact that the base
portion 71 is formed with four notches 76 according to the ninth
embodiment, two or three or not less than five notches may be
formed with equal effect.
[0204] The base portion-side ribs 78, though formed with a
substantially semicircular section according to the eleventh to
eighteenth embodiments, may alternatively have the section of other
shapes such as triangle or rectangle.
[0205] In similar fashion, according to the fifteenth to eighteenth
embodiments described above, the second base portion-side ribs 78a
are formed to have a substantially semicircular section.
Nevertheless, the section may be in any of other shapes including a
triangle and a rectangle.
[0206] While the invention has been described by reference to
specific embodiments chosen for purposes of illustration, it should
be apparent that numerous modifications could be made thereto, by
those skilled in the art, without departing from the basic concept
and scope of the invention.
* * * * *