U.S. patent application number 10/136086 was filed with the patent office on 2002-11-14 for cooling device boiling and condensing refrigerant.
Invention is credited to Sugito, Hajime, Tanaka, Hiroshi.
Application Number | 20020166655 10/136086 |
Document ID | / |
Family ID | 27346682 |
Filed Date | 2002-11-14 |
United States Patent
Application |
20020166655 |
Kind Code |
A1 |
Sugito, Hajime ; et
al. |
November 14, 2002 |
Cooling device boiling and condensing refrigerant
Abstract
A cooling device boiling and condensing refrigerant includes a
refrigerant container, a header tank, and tubes between the
refrigerant container and the header tank. In the cooling device,
each of the refrigerant container and the header tank has a stack
structure constructed by stacking plural plates. Each plate is a
press member formed by punching a metal plate using a press die.
Accordingly, each capacity of the refrigerant container and the
header tank can be readily changed in accordance with a thermal
load, and the plates having the same shape can be used in common
for both the refrigerant container and the header tank.
Inventors: |
Sugito, Hajime;
(Nagoya-city, JP) ; Tanaka, Hiroshi;
(Toyoake-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
27346682 |
Appl. No.: |
10/136086 |
Filed: |
May 1, 2002 |
Current U.S.
Class: |
165/104.21 ;
165/104.33 |
Current CPC
Class: |
H01L 2924/00 20130101;
F28D 15/0233 20130101; H01L 2924/0002 20130101; F28D 15/0266
20130101; H01L 2924/0002 20130101 |
Class at
Publication: |
165/104.21 ;
165/104.33 |
International
Class: |
F28D 015/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 11, 2001 |
JP |
2001-141014 |
Jul 27, 2001 |
JP |
2001-227260 |
Apr 15, 2002 |
JP |
2002-112563 |
Claims
What is claimed is:
1. A cooling device for cooling a heat-generating member,
comprising: a refrigerant container constructed by stacking a
plurality of plates for defining a space where refrigerant is
stored, the plurality of plates including a first plate to which
the heat-generating member is attached, a second plate disposed
opposite to the first plate and at least a third plate between the
first plate and the second plates; and a heat radiation core
including a plurality of tubes attached to the second plate of the
refrigerant container substantially vertically to a surface of the
second plate, to communicate with the space of the refrigerant
container, and a header tank constructed by stacking a plurality of
plates, through which the tubes communicate with each other,
wherein the refrigerant container and heat radiation core are
disposed in such a manner that, refrigerant is boiled by receiving
heat from the heat-generating member attached to the first plate of
the refrigerant container, and the boiled refrigerant flows into
the tubes to radiate heat to outside in the heat radiation
core.
2. The cooling device according to claim 1, wherein: the plurality
of tubes includes first tubes through which refrigerant mainly
flows from the refrigerant container into the header tank, and
second tubes through which refrigerant mainly flows from the header
tank into the refrigerant container; the refrigerant container has
therein a first barrier portion for restricting refrigerant from
flowing into the second tubes; and the header tank has therein a
second barrier portion for restricting refrigerant from flowing
into the first tubes.
3. The cooling device according to claim 1, wherein the header tank
has a capacity smaller than a capacity of the refrigerant
container.
4. The cooling device according to claim 1 wherein each plate
constructing the refrigerant container has a surface area larger
than that of each plate constructing the header tank.
5. The cooling device according to claim 1, wherein at least one of
the plates constructing the refrigerant container has the same
shape as at least one of the plates constructing the header
tank.
6. The cooling device according to claim 1, wherein another
heat-generating member is attached to the plate disposed at a most
outside of the header tank.
7. The cooling device according to claim 6, wherein: the plurality
of tubes includes first tubes through which gas refrigerant boiled
in the refrigerant container flows from the refrigerant container
to the header tank, and second tubes through which gas refrigerant
boiled in the header tank flows from the header tank to the
refrigerant container; the refrigerant container has therein a
first barrier portion for restricting gas refrigerant from flowing
into the second tubes; and the header tank has therein a second
barrier portion for restricting gas refrigerant from flowing into
the first tubes.
8. The cooling device according to claim 1, wherein the tubes are
disposed on the second plate of the refrigerant container in
zigzag.
9. The cooling device according to claim 1, wherein: the plurality
of tubes includes first tubes each having an insertion length
inserted into the header tank, and second tubes each having an
insertion length inserted into the header tank, smaller than that
of each first tube; and each first tube protrudes from an inner
surface of the header tank inside the header tank by a
predetermined length.
10. The cooling device according to claim 1, wherein: the plurality
of tubes includes first tubes each having an insertion length
inserted into the refrigerant container, and second tubes each
having an insertion length inserted into the refrigerant container,
larger than that of each first tube; and each second tube protrudes
from an inner surface of the refrigerant container inside the
refrigerant container by a predetermined length.
11. The cooling device according to claim 9, wherein: each second
tube has an insertion length inserted into the refrigerant
container, larger than that of each first tube inserted into the
refrigerant container; and each second tube protrudes from an inner
surface of the refrigerant container inside the refrigerant
container by a predetermined length.
12. The cooling device according to claim 9, wherein: the
heat-generating member is attached onto the first plate in an
attachment area; and the first tubes are disposed on the second
plate within an area corresponding to the attachment area, and the
second tubes are disposed on the second plate of the refrigerant
container outside the area corresponding to the attachment
area.
13. The cooling device according to claim 9, wherein the insertion
length of each second tube inserted into the header tank is set to
be substantially equal to a plate thickness of the plate of the
header tank, into which each second tube is inserted.
14. The cooling device according to claim 11, wherein the insertion
length of each first tube inserted into the refrigerant container
is set to be substantially equal to a plate thickness of the second
plate of the refrigerant container.
15. The cooling device according to claim 1, wherein one of each
tube and the header tank includes a first insertion regulating
member for regulating the insertion length of the tube inserted
into the header tank.
16. The cooling device according to claim 15, wherein: the first
insertion regulating member is a step portion provided at an end of
the tube; the step portion has a surface substantially
perpendicular to an insertion direction of the tube; and the
surface of the step portion contacts the header tank when the tube
is connected to the header tank.
17. The cooling device according to claim 15, wherein: the first
insertion regulating member is a step portion provided in the
header tank around an insertion hole of the header tank, into which
the tube is inserted to communicate with the header tank; the step
portion has a surface substantially perpendicular to the insertion
direction of the tube; and a top end of the tube contacts the
surface of the step portion when the tube is inserted into the
insertion hole.
18. The cooling device according to claim 1, wherein: the header
tank includes: a first plate defining a plurality of first holes
into which the tubes are inserted; and a second plate with which
the first plate is stacked, the second plate defining a plurality
of second holes each having an open area smaller than an open area
of each first hole; and the tube is inserted into the first hole to
contact the second plate around the second hole to communicate with
the second hole.
19. The cooling device according to claim 1, wherein one of each
tube and the refrigerant container includes a second insertion
regulating member for regulating the insertion length of the tube
inserted into the refrigerant container.
20. The cooling device according to claim 19, wherein: the second
insertion regulating member is a step portion provided at an end of
the tube; the step portion has a surface substantially
perpendicular to an insertion direction of the tube; and the
surface of the step portion contacts the second plate of the
refrigerant container when the tube is connected to the header
tank.
21. The cooling device according to claim 19, wherein: the second
insertion regulating member is a step portion provided in the
second plate of the refrigerant container around an insertion hole
into which the tube is inserted to communicate with the refrigerant
container; the step portion has a surface substantially
perpendicular to the insertion direction of the tube; and a top end
of the tube contacts the surface of the step portion when the tube
is inserted into the insertion hole.
22. The cooling device according to claim 1, wherein: the second
plate of the refrigerant container defines a first hole into which
the tube is inserted; one of the third plate stacked on the second
plate defines a second hole having an open area smaller than an
open area of the first hole of the second plate; and the tube is
inserted into the first hole of the second tube to contact the one
of the third plates around the second hole to communicate with the
second hole of the one of the third plates.
23. The cooling device according to claim 1, wherein: the heat
radiation core is disposed to perform heat exchange between the
refrigerant flowing through the tubes and air passing through the
heat radiation core outside the tubes; and the heat radiation core
is disposed to be divided into at least two core parts in a flow
direction of air passing through the heat radiation core.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to and claims priority from
Japanese Patent Applications No. 2001-141014 filed on May 11, 2001,
No. 2001-227260 filed on Jul. 27, 2001 and No. 2002-112563 filed on
Apr. 15, 2002, the contents of which are hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a cooling device for
cooling a heat-generating member by movement of latent heat based
on boiling and condensation of refrigerant.
[0004] 2. Description of Related Art
[0005] As shown in FIG. 39, in a conventional cooling device 100
constructed by a refrigerant container 110 and a heat radiation
core 120, a heat-generating member 130 is attached to a heat
reception plate of the refrigerant container 110. The heat
radiation core 120 is constructed by a pair of header tanks 121,
plural tubes (heat radiation tubes) 122 and heat radiation fins
123. The header tanks 121 are attached to a heat radiation plate
111 of the refrigerant container 110 to be substantially
perpendicular to the heat radiation plate 111. Each of the tubes
122 is disposed between the header tanks 121 to communicate with
the header tanks 121. Refrigerant stored in the refrigerant
container 110 is boiled and evaporated by receiving heat from the
heat-generating member 130, and the evaporated refrigerant (gas
refrigerant) flows into the tubes 122 from the refrigerant
container 110 through the header tanks 121. The gas refrigerant
radiates heat to outside air and is condensed to be liquid
refrigerant while flowing through the tubes 122, and the condensed
refrigerant (liquid refrigerant) is returned into the refrigerant
container 110. Thus, the heat-generating member 130 is cooled.
[0006] In the cooling device 100, when the tube 122 is inserted
deeply into the header tank 121, an opening of the tube 122 may be
closed by an inner surface of the header tank 121. When the
thickness of the header tank 121 is set larger in order to prevent
the opening of the tube 122 from being closed, the capacity of the
tubes 122 is reduced, and heat radiation performance of the heat
radiation core 120 is also reduced, thereby reducing cooling
performance of the cooling device 100. In addition, when the
cooling device 100 is used in a bottom posture where the
heat-generating member 130 is positioned under the refrigerant
container 110, refrigerant circulation fails and heat radiation
performance is reduced.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing problems, it is an object of the
present invention to provide a cooling device which improves a
refrigerant circulation by reducing interference between gas
refrigerant and liquid refrigerant in tubes, so that cooling
performance is improved.
[0008] It is an another object of the present invention to provide
a cooling device where cooling performance can be improved while a
thickness of a header tank is reduced.
[0009] It is a further another object of the present invention to
provide a cooling device where a capacity of a header tank can be
readily changed and production cost can be reduced, while the
cooling capacity can be improved.
[0010] According to the present invention, in a cooling device for
cooling a heat-generating member by boiling and condensing
refrigerant, refrigerant is boiled by receiving heat from a
heat-generating member attached to a refrigerant container, and
flows into a header tank through plural tubes to radiate heat to
outside in a heat radiation core. In the cooling device, the
refrigerant container is constructed by stacking a plurality of
plates to define a space where refrigerant is stored, and the
header tank is also constructed by stacking a plurality of plates.
Therefore, the plates having the same shape can be used in common
for both the refrigerant container and the header tank, and the
cooling device can be manufactured in low cost. In addition, in the
cooling device, the capacity of the header tank or the refrigerant
container can be readily changed in accordance with a thermal load
in the heat-generating member, only by increasing or decreasing the
number of the plates. Accordingly, cooling performance in the
cooling device can be improved while being manufactured in low
cost.
[0011] Preferably, the plurality of tubes includes first tubes
through which refrigerant flows from the refrigerant container to
the header tank and second tubes through which refrigerant flows
from the header tank to the refrigerant container. Further, a first
barrier portion, for restricting refrigerant from flowing into the
second tube, is provided in the refrigerant container, and a second
barrier portion, for restricting refrigerant from flowing into the
first tube, is provided in the header tank. Accordingly, gas
refrigerant, boiled by receiving heat from the heat-generating
member in the refrigerant container flows into the first tubes, and
liquid refrigerant in the header tank can be returned into the
refrigerant container through the second tubes. Therefore, it can
restrict an interference between the gas refrigerant from the
refrigerant container to the header tank, and the liquid
refrigerant from the header tank to the refrigerant container,
thereby improving refrigerant circulation and cooling
performance.
[0012] Alternatively, in the cooling device, the plurality of tubes
includes first tubes each having an insertion length inserted into
the header tank, and second tubes each having an insertion length
inserted into the header tank, smaller than that of each first
tube. Each first tube protrudes from an inner surface of the header
tank inside the header tank by a predetermined length. Accordingly,
an amount of liquid refrigerant introduced into the first tubes
from the header tank is reduced. On the contrary, an amount of
liquid refrigerant introduced into the second tubes from the header
tank is increased. As a result, the amount of gas refrigerant
flowing into the first tubes from the refrigerant container is
increased, thereby improving the refrigerant circulation.
[0013] Preferably, the header tank includes a first plate defining
a plurality of first holes into which the tubes are inserted, and a
second plate on which the first plate is stacked. The second plate
defines a plurality of second holes each having an open area
smaller than an open area of each first hole, and the tube is
inserted into the first hole to contact the second plate around the
second hole to communicate with the second hole. Accordingly, each
tube can be readily positioned at a predetermined position in a
stack direction of the plates without using an additional part such
as spacers. Therefore, it can prevent an opening portion in each
tube from contacting an inner surface of the header tank, while the
thickness of the header tank can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Additional objects and advantages of the present invention
will be more readily apparent from the following detailed
description of preferred embodiments when taken together with the
accompanying drawings, in which:
[0015] FIG. 1 is a schematic side view showing a cooling device
according to a first embodiment of the present invention;
[0016] FIG. 2 is a schematic sectional view showing the cooling
device taken along line II-II in FIG. 1;
[0017] FIG. 3A is a plan view showing a heat radiation plate
constructing a refrigerant container of the cooling device,
[0018] FIG. 3B is a plan view showing an intermediate plate
constructing the refrigerant container,
[0019] FIG. 3C is a plan view showing an intermediate plate
constructing the refrigerant container, and
[0020] FIG. 3D is a plan view showing a heat reception plate
constructing the refrigerant container, according to the first
embodiment;
[0021] FIG. 4 is a sectional view showing a stopper structure of
the refrigerant container according to the first embodiment;
[0022] FIG. 5 is a schematic side view showing a cooling device
according to a second embodiment of the present invention;
[0023] FIG. 6 is a schematic sectional view of the cooling device
taken along line VI-VI in FIG. 5;
[0024] FIG. 7A is a plan view showing a heat radiation plate
constructing a refrigerant container of the cooling device
according to the second embodiment,
[0025] FIG. 7B is a plan view showing an intermediate plate
constructing the refrigerant container,
[0026] FIG. 7C is a plan view showing an intermediate plate
constructing the refrigerant container, and
[0027] FIG. 7D is a plan view showing a heat reception plate
constructing the refrigerant container;
[0028] FIG. 8 is a schematic side view showing a cooling device
according to a third embodiment of the present invention;
[0029] FIG. 9 is a schematic side view showing a cooling device
according to a fourth embodiment of the present invention;
[0030] FIG. 10 is a schematic sectional view showing the cooling
device, used in a bottom posture, taken along line X-X in FIG.
9;
[0031] FIG. 11 is a schematic sectional view showing the cooling
device, used in a side posture, in FIG. 9;
[0032] FIG. 12 is a plan view showing a heat radiation plate
according to a fifth embodiment of the present invention;
[0033] FIG. 13 is a plan view showing an another heat radiation
plate according to the fifth embodiment;
[0034] FIG. 14 is a plan view showing an another heat radiation
plate according to the fifth embodiment;
[0035] FIG. 15 is a plan view showing an another heat radiation
plate according to the fifth embodiment;
[0036] FIG. 16 is a schematic side view showing a cooling device
according to a sixth embodiment of the present invention;
[0037] FIG. 17 is a schematic sectional view showing the cooling
device according to the sixth embodiment;
[0038] FIG. 18 is a schematic sectional view showing the cooling
device taken along line XVIII-XVIII in FIG. 16;
[0039] FIG. 19 is a schematic sectional view showing a stopper
structure in a refrigerant container of a cooling device according
to a seventh embodiment of the present invention;
[0040] FIG. 20 is a schematic sectional view showing a part of a
cooling device around an attachment portion between tubes and a
header tank according to an eighth embodiment of the present
invention;
[0041] FIG. 21 is a schematic sectional view showing a part of the
cooling device around an attachment portion of tubes and a
refrigerant container according to the eighth embodiment;
[0042] FIG. 22 is a perspective view showing the cooling device
according to the eighth embodiment;
[0043] FIG. 23 is a schematic sectional view showing a cooling
device according to a ninth embodiment of the present
invention;
[0044] FIG. 24 is a schematic sectional view showing a cooling
device according to a tenth embodiment of the present
invention;
[0045] FIG. 25 is a schematic sectional view showing a part of a
cooling device around an attachment portion of tubes and a
refrigerant container, according to an eleventh embodiment of the
present invention;
[0046] FIG. 26 is a schematic sectional view showing a cooling
device according to a twelfth embodiment of the present
invention;
[0047] FIG. 27A is a schematic sectional view showing an insertion
structure of a tube into a header tank of a cooling device
according to a thirteenth embodiment of the present invention,
and
[0048] FIG. 27B is a schematic sectional view showing another
insertion structure of the tube into the header tank according to
the thirteenth embodiment;
[0049] FIG. 28 is a schematic sectional view showing a part of a
reference cooling device around an attachment portion of tubes and
a header tank, for explaining the thirteenth embodiment;
[0050] FIG. 29 is a schematic sectional view showing a part of an
another reference cooling device for explaining the thirteenth
embodiment;
[0051] FIG. 30 is a schematic sectional view showing a cooling
device, used in a side posture, according to a fourteenth
embodiment of the present invention;
[0052] FIG. 31 is a schematic sectional view showing a cooling
device, used in a bottom posture, according to the fourteenth
embodiment;
[0053] FIG. 32 is a schematic sectional view showing a cooling
device having two header tanks divided from each other, according
the fourteenth embodiment;
[0054] FIG. 33A is a schematic diagram showing an insertion state
of a tube into a refrigerant container and a header tank in a
fifteenth embodiment of the present invention, and
[0055] FIG. 33B is a schematic sectional view showing a part of the
refrigerant container according to the fifteenth embodiment;
[0056] FIG. 34 is a plan view showing an end surface of a tube
according to the fifteenth embodiment;
[0057] FIG. 35 is a side view showing a part of the refrigerant
container when being viewed from an arrow B in FIG. 33B;
[0058] FIG. 36 is a sectional view showing a part of the
refrigerant container taken along line XXXVI-XXXVI in FIG. 35;
[0059] FIG. 37 is a schematic diagram showing a tube insertion
state when being viewed from arrow A in FIG. 33A;
[0060] FIG. 38 is a schematic sectional view showing a cooling
device according to a modification of the present invention;
and
[0061] FIG. 39 is a perspective view showing a conventional cooling
device.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0062] Preferred embodiments of the present invention will be
described hereinafter with reference to the accompanying
drawings.
[0063] A first embodiment of the present invention will be now
described with reference to FIGS. 1-4. As shown in FIG. 1, a
cooling device 1 according to the first embodiment is constructed
by a refrigerant container 2 and a heat radiation core 3. In the
cooling device 1, a heat-generating member 4 is fixed to a bottom
surface of the refrigerant container 2 substantially at a center by
using screws 5. For example, the heat-generating member 4 is a
computer chip mounted on a printed circuit board. Further, the
refrigerant container 2 has a stack structure constructed by
stacking plural plates 6, for example, four plates 6.
[0064] FIG. 2 is a cross-sectional view taken along line II-II in
FIG. 1. The refrigerant container 2 defines a refrigerant chamber 7
therein as shown in FIG. 2, and a predetermined amount of
refrigerant is stored in the refrigerant chamber 7. In FIGS. 3A-3D,
each plate 6 (6A, 6B, 6C, 6D) is a press member formed by punching
a metal plate such as an aluminum plate or a stainless steel plate
using a press die. Further, the metal plate may be a brazing sheet
where a brazing material layer is beforehand provided on a surface
of a metal sheet. Specifically, the plates 6 include a heat
reception plate 6A, a heat radiation plate 6B and two (three or
more) intermediate plates 6C. The heat reception plate 6A and the
heat radiation plate 6B are disposed at both outside of the
refrigerant container 2, and the intermediate plates 6C are
sandwiched between the outside plates 6A, 6B.
[0065] As shown in FIGS. 3A-3D, four attachment holes 6a, into
which the screws are screwed for fixing the heat-generating member
4 to the heat reception plate 6A, are provided in each of the
plates 6 as through holes in a stack direction of the plates 6.
Plural openings 6b, into which tubes 8 of the heat radiation core 3
are inserted, are provided in the heat radiation plate 6B, as shown
in FIG. 3A. As shown in FIGS. 3B, 3C, plural slits 6c are provided
in two patterns A, B in the intermediate plates 6C substantially
over all the surface, respectively. In the pattern A shown in FIG.
3B, the slits 6c are provided to extend in a longitudinal direction
of the intermediate plate 6C. In the pattern B shown in FIG. 3C,
the slits 6c are provided to extend in a direction perpendicular to
the longitudinal direction of the intermediate plate 6C. The slits
6c of the pattern A and the slits 6c of the pattern B are provided
to communicate with each other, and to define the refrigerant
chamber 7. Further, metal portions are provided between the slits
6c, to form a thermal conductor in the stack direction of the
intermediate plates 6C when the intermediate plates 6C are stacked.
The heat reception plate 6A and the heat radiation plate 6B are
thermally connected to each other by the thermal conductor of the
intermediate plates 6C.
[0066] The intermediate plate 6C with the pattern A shown in FIG.
3B, stacked with the heat radiation plate 6B, includes tube
stoppers 6d (metal portions) each for stopping a further insertion
of the tube 8 inserted into the opening 6b of the heat radiation
plate 6B. Specifically, as shown in FIG. 4, when the intermediate
plate 6C is stacked with the heat radiation plate 6B, a part of the
metal portion (where the slit 6c is not provided) of the
intermediate plate 6C covering the opening 6b is used as the
stopper 6d, in the opening 6b of the heat radiation plate 6B. Thus,
the tube 8, inserted into the opening 6b of the heat radiation
plate 6B, contacts the stopper 6d and is positioned at a
predetermined position in the stack direction of the plates 6.
[0067] For example, the heat radiation core 3 is constructed by
plural tubes (e.g., 15 tubes) 8, a header tank 9 and heat radiation
fins 10. One end of each tube 8 in a tube longitudinal direction is
attached to the heat radiation plate 6B of the refrigerant
container 2, and the other end of each tube 8 is attached to the
header tank 9, so that the plural tubes 8 communicate with each
other through the header tank 9. The radiation fins 10 such as
corrugated fins are disposed between the adjacent tubes 8. The
header tank 9 is also a stack structure constructed by stacking
plural plates (e.g., four plates) 6 as in the refrigerant container
2. In the header tank 9, the attachment holes 6a are not provided
in the plural plates 6, or are closed. One side ends of the tubes 8
are inserted into the openings 6b of the heat radiation plate 6B of
the refrigerant container 2 to communicate the refrigerant chamber
7, and the other side ends of the tubes 8 are inserted into the
header tank 9 to communicate with the header tank 9. After the
cooling device 1 is temporarily assembled to an assemble body, the
assemble body is integrally brazed in a vacuum, for example.
[0068] Next, the cooling device 1 according to the first embodiment
will be now described. As shown in FIGS. 1 and 2, the cooling
device 1 according to the first embodiment is used in a bottom
posture where the heat-generating member 4 is located at a lower
side of the refrigerant container 2 and the heat radiation core 3
is located at an upper side of the refrigerant container 2.
[0069] Refrigerant stored in the refrigerant container 2
(refrigerant chamber 7) is boiled and evaporated by receiving heat
from the heat-generating member 4, and flows from the refrigerant
chamber 7 into the header tank 9 mainly through the tubes 8
positioned in an attachment area of the heat-generating member 4
(i.e., area indicated by one-dot chain lines in FIG. 3A). The gas
refrigerant flowing toward the header tank 9 through the tubes 8 is
cooled and condensed while being distributed in the header tank 9.
The condensed refrigerant (liquid refrigerant) is returned to the
refrigerant chamber 7 through the tubes 8 disposed outside the
attachment area of the heat-generating member 4. Thus, heat is
transmitted from the heat-generating member 4 to refrigerant, and
is further transferred to the heat radiation core 3 through the
refrigerant. Thereafter, the heat is radiated as condensation
latent heat while gas refrigerant is condensed in the heat
radiation core 3, and is discharged to atmospheric air through the
heat radiation fins 10.
[0070] Next, operational effects of the first embodiment will be
described. In the cooling device 1 according to the first
embodiment, each of the refrigerant container 2 and the header tank
9 is constructed by stacking the plural plates (press material) 6,
and the plural plates 6 can be used in common for both the
refrigerant container 2 and the header tank 9. Therefore, each
plate 6 used for the refrigerant container 2 and the corresponding
plate 6 used for the header tank 9 can be formed by a common press
die. Accordingly, the number of expensive press dies can be
reduced, and production cost of the cooling device 1 can be largely
reduced. Further, the kinds of the plates 6 can be reduced by the
plural plates 6 used in common for both the refrigerant container 2
and the header tank 9, thereby simplifying management of
compartments of the cooling device.
[0071] In addition, the capacity of the refrigerant container 2 and
the capacity of the header tank 9 can be readily changed only by
increasing and reducing the number of the plates 6. Accordingly,
the capacity of the refrigerant container 2 and the capacity of the
header tank 9 can be readily changed in accordance with increase
and decrease of thermal loads. In this case, since a new press die
is not required even when the number of the plates 6 is increased,
specifications for the cooling device can be readily changed in low
cost, in the first embodiment.
[0072] Further, a surface area of the thermal conductor, formed by
the metal portions of the intermediate plates 6C, can be changed
only by changing shapes of the slits 6c thereof. Therefore, the
heat radiation performance of the cooling device 1 can be increased
without inner fins provided in the refrigerant chamber 7 of the
refrigerant container 2. Further, as shown in FIG. 4, each of the
refrigerant container 2 and the header tank 9 has the stack
structure, and the stoppers 6d are provided in the intermediate
plate 6C. Therefore, the tubes 8 can be readily inserted at a
predetermined position in the stack direction without using an
additional member such as spacers. Accordingly, an insertion length
of the tubes 8 inserted into the refrigerant container 2 and the
header tank 9 can be readily regulated.
[0073] A second embodiment of the present invention will be
described with reference to FIGS. 5, 6 and 7A-7D. In the second
embodiment, the present invention is used for a cooling device 1
where the tubes 8 cannot be disposed in the attachment area of the
heat-generating member 4, as shown in FIG. 5. As shown in FIG. 7B,
the openings 6b are provided in the heat radiation plate 6B at both
sides outside the attachment area of the heat-generating member 4
(area indicated by one-dot chain lines). That is, no opening 6b is
provided in the attachment area of the heat-generating member 4.
Further, barrier portions 11, for restricting a flow of the
condensed refrigerant (liquid refrigerant) returned from the header
tank 9 to the refrigerant container 2, are provided in the
intermediate plates 6c of the refrigerant container 2.
Specifically, an intermediate plate 6C having slits 6c of the
pattern A shown in FIG. 7B is stacked onto an intermediate plate 6C
having slits 6c of the pattern B shown in FIG. 7C. The barrier
portions 11 are formed by stacking metal portions of the
intermediate plates 6C.
[0074] Accordingly, as shown in FIG. 6, the refrigerant, boiled by
receiving the heat from the heat-generating member 4, flows into
the header tank 9 through the tubes 8 (first tube) around the
attachment area of the heat-generating member 4. The boiled
refrigerant (gas refrigerant) is cooled and condensed while being
distributed into the header tank 9, and the condensed refrigerant
(liquid refrigerant) is returned to the refrigerant container 2
through the tubes 8 (second tubes) away from the attachment area.
As indicated by broken-line arrows in FIG. 7C, circulation roots of
refrigerant are formed in the refrigerant container 2 by
restricting the refrigerant flow using the barrier portions 11.
Thus, refrigerant circulation is facilitated, and heat radiation
performance can be improved.
[0075] A third embodiment of the present invention will be now
described with reference to FIG. 8, In a cooling device 1 of the
third embodiment, a size of the refrigerant container 2 is
different from a size of the header tank 9. Specifically, as shown
in FIG. 8, the size of the header tank 9 is made smaller than the
size of the refrigerant container 2, and a refrigerant inlet pipe
12, from which refrigerant is filled in the refrigerant container 2
(refrigerant chamber 7), is set in the refrigerant container 2 so
as not to interfere with the header tank 9. Accordingly, the
refrigerant inlet pipe 12 can be readily provided in the
refrigerant container 2, while the tube insertion position can be
accurately set.
[0076] A fourth embodiment of the present invention will be now
described with reference to FIGS. 9-11. In the fourth embodiment,
the present invention is used for a cooling device 1 where the
capacity of the header tank 9 is made smaller than the capacity of
the refrigerant container 2 as shown in FIG. 9. Further, as shown
in FIG. 10, the cooling device 1 may be used in a bottom posture
where the refrigerant container 2 is disposed horizontally and the
heat-generating member 4 is attached onto the bottom surface of the
refrigerant container 2. Alternatively, as shown in FIG. 11, the
cooling device 1 may be used in a side posture where the
refrigerant container 2 is disposed vertically and the
heat-generating member 4 is attached to the refrigerant container 2
on its side surface. When the cooling device 1 is used in the
bottom posture, the cooling performance of the cooling device 1 is
reduced when liquid refrigerant flows into the tubes 8 from the
refrigerant container 2. Therefore, the liquid refrigerant surface
is need to be made lower as well as possible. On the other hand,
when the cooling device 1 is used in the side posture, refrigerant
dries excessively around the heat-generating member 4 when the
liquid refrigerant surface is made excessively lower. Therefore,
liquid refrigerant surface is need to be set higher in accordance
with an attachment position of the heat-generating member 4. In
view of the above-described problem, the capacity of the header
tank 9 is need to be set smaller than the capacity of the
refrigerant container 2.
[0077] Specifically, when the cooling device 1 is used in the side
posture shown in FIG. 11, liquid refrigerant enters into the header
tank 9 and the refrigerant container 2. Therefore, as the capacity
of the header tank 9 increases, the liquid refrigerant surface in
the refrigerant container 2 becomes lower. The liquid refrigerant
surface in the refrigerant container 2 can be increased by reducing
the capacity of the header tank 9. Further, refrigerant in the
refrigerant container 2 is need to be boiled, and heat from the
heat-generating member 4 is need to be transmitted to refrigerant
through the refrigerant container 2. Therefore, it is necessary to
enlarge the capacity of the refrigerant container 2.
[0078] That is, in the fourth embodiment, by setting the capacity
of the header tank 9 to be smaller than the capacity of the
refrigerant container 2, sufficient cooling performance can be
obtained in both the bottom posture and the side posture of the
cooling unit 1.
[0079] A fifth embodiment of the present invention will be now
described with reference to FIGS. 12-15. In the fifth embodiment,
the heat radiation fins 10 described in the above first embodiment
are eliminated from a cooling device 1. Generally, the heat
radiation fins 10 are provided for increasing a heat radiation area
on an air side and for improving the cooling performance of the
cooling device 1. However, an amount of cooling air passing through
the cooling device is reduced by an excessive pressure loss in the
heat radiation fins 10. Especially in a cooler for a personal
computer, a server and the like used in an office, a noise is
strongly required to be reduced while an excessively large electric
load is required for the cooling fan.
[0080] In the fifth embodiment, the heat radiation fins 10 are
eliminated, thereby solving problems such as increase of the number
of fin attachment processes and deviation of fin set positions in
fin attachment work. Further, the pressure loss at the air side can
be greatly reduced, thereby improving the cooling performance of
the cooling device 1 and reducing the noises thereof. Furthermore,
since the heat radiation fins 10 are eliminated, the tubes 8 can be
set at arbitrary positions, respectively. For example, as shown in
FIG. 12, the tubes 8 can be disposed in zigzag so as to efficiently
radiate heat. For example, as shown in FIG. 13, the tubes 8 can be
disposed in zigzag so that the neighboring tubes 8 are not
overlapped with each other in a direction perpendicular to the
longitudinal direction of the heat radiation plate 6B, thereby
improving attachment performance of the tubes 8. For example, as
shown in FIG. 14, the heat radiation fins 10 can be partially
provided between tubes 8 in a part of the tubes 8.
[0081] When no heat radiation fin 10 is used, the number of the
tubes 8 can be increased, thereby facilitating refrigerant
circulation of the cooling device 1, and effectively improving heat
radiation performance thereof. The tube 8 has a sectional shape
with high heat-transmitting efficiency such as an oval shape. For
example, as shown in FIG. 15, the tube 8 may be a hollow pin.
[0082] A sixth embodiment of the present invention will be now
described with reference to FIGS. 16-18. In a cooling device 1 of
the sixth embodiment, a first heat-generating member 4 is attached
to the refrigerant container 2 and a second heat-generating member
13 is attached to the header tank 9, as shown in FIG. 16. Since the
header tank 9 has the stack structure identical to the stack
structure of the refrigerant container 2, the second
heat-generating member 13 can be readily attached to the header
tank 9 as in the refrigerant container 2. Thus, both the
heat-generating members 4, 13 can be cooled by using the single
cooling device 1 at the same time, thereby reducing total cost for
this cooling system. However, when the second heat-generating
member 13 is also attached to the header tank 9, gas refrigerant
generated in the header tank 9 collides with gas refrigerant
generated in the refrigerant container 2, so that refrigerant
circulation may fail. Therefore, the refrigerant flow is need to be
carefully controlled to prevent the refrigerant circulation
failure.
[0083] In the sixth embodiment, as shown in FIGS. 17, 18, barrier
portions 11 (11A, 11B) for controlling each refrigerant flow are
provided in the refrigerant container 2 and the header tank 9,
respectively, thereby facilitating the refrigerant circulation.
[0084] Specifically, as shown in FIG. 17, the barrier portion 11
(11A, 11B) are provide to divide first tubes 8A and second tubes 8B
in the tubes 8. Gas refrigerant, boiled by receiving heat from the
first heat-generating member 4 in the refrigerant container 2,
flows toward the header tank 9 through the first tubes 8A. Gas
refrigerant, boiled by receiving heat from the second
heat-generating member 13 in the header tank 9, flows toward the
refrigerant container 2 through the second tubes 8B. In the
refrigerant container 2, the first barrier portions 11A are
provided to restrict the gas refrigerant, boiled by receiving heat
from the first heat-generating member 4, from flowing into the
second tubes 8B. In the header tank 9, the second barrier portions
11B are provided to restrict the gas refrigerant, boiled by
receiving heat from the second heat-generating member 13, from
flowing into the first tubes 8A. Thus, as indicated by arrows in
FIGS. 17, 18, the gas refrigerant boiled in the refrigerant
container 2 does not collide with the gas refrigerant boiled in the
header tank 9, and the gas refrigerant can satisfactorily circulate
between the refrigerant container 2 and the header tank 9.
Therefore, the first and second heat-generating members 4, 13 can
be effectively cooled. Here, each of the first and second barrier
portions 11A, 11B can be readily provided by stacking the metal
portions of the intermediate plates 6C. That is, it is unnecessary
to use additional members as the barrier portions 11 (11A,
11B).
[0085] A seventh embodiment of the present invention will be now
described with reference to FIG. 19. In the seventh embodiment,
attachment structures between the tubes 8 and the refrigerant
container 2 and between the tubes 8 and the header tank 9 are
described. Here, when the plural plates 6 are connected to each
other by brazing, they are need to be accurately pressed to each
other. In the seventh embodiment, as shown in FIG. 19, a notch 8a
is provided in the tube 8 at an end inserted into the opening 6b of
the heat radiation plate 6B. When a pressure is applied to the
plates 6 through the notch 8a in each tube 8, the plates 6 can be
accurately pressed to each other, thereby preventing brazing
failure. Further, through the notch 8a, each tube can be accurately
inserted into the refrigerant container 2 at a predetermined
position. The same attachment structure can be used for that
between the header tank 9 and the tubes 8. Even in this case, the
same effect can be obtained.
[0086] An eighth embodiment of the present invention will be now
described with reference to FIGS. 20-22. In the eighth embodiment,
an insertion length of a gas refrigerant tube (gas tube) 8C
inserted into the header tank 9 is set different from that of a
liquid refrigerant tube (liquid tube) 8D inserted into the header
tank 9. As shown in FIG. 20, gas refrigerant flows into the header
tank 9 from the refrigerant container 2 through the gas tube 8C. As
shown in FIG. 21, liquid refrigerant flows into the refrigerant
container 2 from the header tank 9 through the liquid tube 8D.
Specifically, as shown in FIG. 20, an insertion length L1 of the
gas tube 8C inserted into the header tank 9 is set larger than a
plate thickness t1 of the header tank 9 at the bottom side. That
is, an upper end of the gas tube 8C protrudes from an inner bottom
surface of the header tank 9 inside the header tank 9 by a
predetermined length. On the other hand, an insertion length L2 of
the liquid tube 8D inserted into the header tank 9 is set
substantially equal to the plate thickness t1. That is, an upper
end of the liquid tube 8D does not protrude to the inside of the
header tank 9 from the inner surface of the header tank 9.
[0087] Next, operation of the cooling device 1 according to the
eighth embodiment will be now described. In the eighth embodiment,
the cooling device 1 is used in the bottom posture where the
refrigerant container 2 is disposed horizontally and the
heat-generating member 4 is attached to the refrigerant container 2
on its bottom surface as shown in FIG. 22. The refrigerant stored
in the refrigerant container 2 is boiled by receiving heat from the
heat-generating member 4 in the refrigerant chamber 7. The boiled
gas refrigerant flows mainly through the gas tubes 8C toward the
header tank 9, while being cooled and condensed, and the condensed
refrigerant (liquid refrigerant) is returned into the refrigerant
chamber 7 through the liquid tubes 8D.
[0088] Since the gas tubes 8C protrude from the inner bottom
surface of the header tank 9 to the inside thereof, the liquid
refrigerant hardly flows into the gas tubes 8C from the header tank
9 when refrigerant is returned from the header tank 9 to the
refrigerant container 2 through the tubes 8. Therefore, much of the
liquid refrigerant is returned from the header tank 9 to the
refrigerant container 2 through the liquid tubes 8D. As a result,
as shown in FIG. 21, much of the gas refrigerant in the refrigerant
container 2 flows into the gas tubes 8C. Therefore, a flow amount
of the gas refrigerant flowing into the liquid tubes 8D in the
refrigerant container 2 can be made smaller, thereby realizing a
preferable refrigerant circulation in the cooling device 1. Even in
the eighth embodiment, the refrigerant container 2 or the header
tank 9 has the stack structure described in the above first
embodiment.
[0089] In the eighth embodiment, the present invention also can be
used for a cooling device where the refrigerant container 2 has a
hollow structure or has an inner fin.
[0090] A ninth embodiment of the present invention will be now
described with reference to FIG. 23. In the ninth embodiment, the
gas tubes 8C are attached to the refrigerant container 2 in an
attachment area R of the heat-generating member 4. The liquid tubes
8D are attached to the refrigerant container 2 outside the
attachment area R. Specifically, as shown in FIG. 23, the
heat-generating member 4 is attached to the heat reception plate 6A
on an attachment area. Here, the attachment area R is an area
corresponding to the attachment area of the heat-generating member
4 on the heat radiation plate 6B. Since the gas tubes 8C are
disposed in the attachment area R where refrigerant is readily
boiled in the refrigerant container 2, the gas refrigerant
effectively flows into the gas tubes 8C from the refrigerant
container. Further, the liquid tubes 8D are disposed outside the
attachment area R, thereby reducing an amount of gas refrigerant
flowing into the liquid tubes 8D from the refrigerant chamber 7.
Therefore, the refrigerant circulation can be realized more
effectively than the above-described eighth embodiment, and the
heat radiation performance of the cooling device 1 can be further
improved.
[0091] A tenth embodiment of the present invention will be now
described with reference to FIG. 24. In the tenth embodiment, the
barrier portions 11 for controlling gas refrigerant flow, described
in the second embodiment, are provided in the refrigerant container
2 of a cooling device 1 according to the ninth embodiment. As shown
in FIG. 24, the barrier portions 11 are provided between the gas
tubes 8C and the liquid tubes 8D. The barrier portions 11 control
the gas refrigerant, boiled by receiving the heat from the
heat-generating member 4, to not flow into the liquid tubes 9B,
thereby realizing the further preferable refrigerant circulation.
In the tenth embodiment, the barrier portions 11 can be readily
formed by changing the shapes of the intermediate plates 6C.
[0092] An eleventh embodiment of the present invention will be now
described with reference to FIG. 25. In the eleventh embodiment, an
insertion length of the gas tube 8C inserted into the refrigerant
container 2 is set different from an insertion length of the liquid
tube 8D inserted into the refrigerant container 2. Specifically, as
shown in FIG. 25, an insertion length L3 of the gas tube 8C into
the refrigerant container 2 is set substantially equal to a plate
thickness t2 of the heat radiation plate 6B. That is, a lower end
of the gas tube 8C does not protrude from the inner surface of the
refrigerant container 2 to an inside thereof. The insertion length
L4 of the liquid tube 8D is set larger than the plate thickness t2.
That is, a lower end of the liquid tube 8D protrudes from the inner
surface of the refrigerant container 2 to the inside thereof.
Accordingly, when the gas refrigerant, boiled in the refrigerant
container 2, flows into the tubes 8, the gas refrigerant does not
flows into the liquid tubes 8D but flows into the gas tubes 8C.
Therefore, the liquid refrigerant is readily returned from the
header tank 9 into the refrigerant container 2 through the liquid
tubes 8D, and the gas refrigerant flowing through the liquid tubes
8D can be restricted, thereby realizing the preferable refrigerant
circulation.
[0093] A twelfth embodiment of the present invention will be
described with reference to FIG. 26. In the twelfth embodiment,
both the feature of the cooling device of the eleventh embodiment
and the feature of the cooling device in the eighth embodiment are
added. Specifically, as shown in FIG. 26, the insertion length of
the gas tube 8C inserted into the header tank 9 is set larger than
the plate thickness of the bottom wall of the header tank 9, and
the insertion length of the gas tube 8C inserted into the
refrigerant container 2 is set equal to the plate thickness of the
heat radiation plate 6B. In addition, the insertion length of the
liquid tube 8D inserted into the header tank 9 is set equal to the
plate thickness of the header tank 9 at the bottom side, and the
insertion length of the liquid tube 8D inserted into the
refrigerant container 2 is set larger than the plate thickness of
the heat radiation plate 6B of the refrigerant container 2. The gas
tubes 8C are disposed in the attachment area R shown in FIG. 24,
and the liquid tubes 8D are disposed outside the attachment area
R.
[0094] Accordingly, much of the gas refrigerant, boiled in the
refrigerant container 2, flows into the gas tubes 8C, and much of
the liquid refrigerant in the header tank 9 flows into the liquid
tubes 8D, thereby effectively forming a refrigerant-circulation
cycle, and realizing the cooling device 1 having high heat
radiation performance. Further, an entire length of the gas tube 8C
can be set equal to an entire length of the liquid tube 8D in FIG.
26. In this case, the management of components of the cooling
device 1 can be simplified, and troubles such as assembling errors
can be eliminated.
[0095] A thirteenth embodiment of the present invention will be now
described with reference to FIGS. 27A-27B, and 28-29. In the
thirteenth embodiment, a joint structure between the header tank 9
and each tube 8 is formed as shown in FIGS. 27A, 27B. It is
preferable that each tube 8 is attached to the header tank 9 while
each upper end of the tubes 8 protrudes into the header tank 9 as
shown in FIG. 28, for improving the brazing performance between the
tubes 8 and the header tank 9 and for preventing an introduction of
a brazing material into the tubes 8. However, in the attachment
structure shown in FIG. 28, liquid refrigerant is stored in the
header tank 9, thereby reducing an amount of the liquid refrigerant
returned into the refrigerant container 2 from the header tank 9,
and reducing the heat radiation performance of the cooling device
1. In order to prevent the liquid refrigerant from being stored in
the header tank 9, it is preferable that each of the tubes 8 does
not protrude into the header tank 9, as shown in FIG. 29.
[0096] According to the thirteenth embodiment of the present
invention, the tubes 8 are attached to the header tank 9, so that
it can prevent the liquid refrigerant from being stored in the
header tank 9 while preventing the brazing material from flowing
into the tubes 8.
[0097] Specifically, as shown in FIG. 27A, insertion holes 6a for
the tubes 8 are provided by burring in the header tank 9. More
specifically, the header tank 9 protrudes outside around each
insertion hole 6a so that a space S is provided between the
inserted tube 8 and the header tank 9. Here, the top end is set at
a position approximately equal to the inner surface of the header
tank 9. Since the brazing material is stored in the space S
provided around the tube 8 inserted to each insertion hole 6a, it
can be effectively prevented the brazing material from flowing into
the tube 8. Further, as shown in FIG. 27B, the insertion holes 6a
can be formed by pressing in the header tank 9. In this case, a
chamfer is provided around each insertion hole 6a, thereby forming
the space S on inner side of the header tank 9. The chamfers may be
provided by cutting. Even in this case, the same effect as that in
FIG. 27 can be obtained.
[0098] A fourteenth embodiment of the present invention will be now
described with reference to FIGS. 30-32. In the fourteenth
embodiment, the tubes 8 are arranged relative to the refrigerant
container 2 and the header tank 9 while being divided to upstream
side tubes and downstream side tubes in a flow direction of cooling
air. As shown in FIG. 30, even when the cooling device 1 is used in
the side posture, refrigerant circulates as indicated by arrows,
thereby improving the heat radiation performance of the cooling
device 1.
[0099] As shown in FIG. 31, when the cooling device 1 is used in
the bottom posture, the heat radiation performance can be improved.
In this case, preferably, the liquid tubes 8D are disposed at the
upstream side of cooling air, and the gas tubes 8C are disposed at
the downstream side thereof, thereby further facilitating the
refrigerant circulation. Since the gas tubes 8C are disposed at the
downstream side of cooling air, the gas tubes 8C can be maintained
at a temperature higher than the liquid tubes 8D. Therefore, gas
refrigerant flowing in the gas tubes 8C can be prevented from being
condensed therein, thereby maintaining the refrigerant circulation.
Further, as shown in FIG. 32, the header tank 9 may be divided to
two portions. That is, the heat radiation core 3 can be divided
into plural parts in the flow direction of cooling air.
[0100] A fifteenth embodiment of the present invention will be now
described with reference to FIGS. 33A, 33B and 34-37. In the
fifteenth embodiment, as shown in FIGS. 33A and 33B, the insertion
lengths of the tubes 8 inserted into the refrigerant container 2
and the header tank 9 are regulated by insertion holes 2a, 9a
provided in the refrigerant container 2 (heat radiation plate 6B)
and the header tank 9, respectively. Specifically, each of the
insertion holes 2a, 9a is provided in a step shape, and each tube 8
is attached to the refrigerant container 2 and the header tank 9
through the insertion holes 2a. 9a. Each tube 8 have plural through
holes 34a (e.g., circular through holes or rectangular through
hoes) extending in the tube longitudinal direction, and both ends
of the tube 8 are formed in the shape shown in FIG. 34. As shown in
FIGS. 33A, 33B, 34-36, a side surface 8b of the tube 8 is fitted to
an inner surface 2b of the insertion hole 2a, and the top end of
the tube 8 contacts a step surface 2c of the insertion hole 2a.
Thus, the insertion length of the tube 2 inserted into the
refrigerant container 2 is restricted. The insertion length of the
tube 8 inserted into the header tank 9 is also restricted in the
same manner.
[0101] Accordingly, the insertion lengths of the tube 8 inserted
into the refrigerant container 2 and the header tank 9 can be
controlled using the insertion holes 2a, 9a provided in the
refrigerant tank 2 and the header tank 9 while no notch 8a shown in
FIG. 19 is provided in the tube 8 at an end inserted into the
insertion holes 2a, 9a. Since the insertion length can be
regulated, the dimensions of the refrigerant container 2 and the
header tank 9 can be reduced in the insertion direction of the tube
8 without closing the through holes 34a of each tube 8 as shown in
FIG. 37. In this embodiment, a dimension of each flat tube 8 in the
tube thickness direction (up-down direction in FIG. 37) is set
approximately equal to a dimension of each insertion hole 2a, 9a in
the same direction as the up-down direction in FIG. 37. For
example, each of the dimension of the flat tube 8 and the dimension
of the hole 2a in the up-down direction of FIG. 37 is approximately
1.7 mm. Further, the dimension between the step surface in the
up-down direction in FIG. 36 is set at 1.5 mm, for example, and
each diameter of the through holes 34a is set at 1.1 mm, for
example. Accordingly, even when the tube 8 is inserted into the
insertion hole 2a, 9a, any through hole 34a is not closed by the
step surface 2c, 9c while the tube insertion length can be
accurately controlled. Therefore, the capacity (height) of each
tube 8 can be enlarged, thereby improving the cooling performance
(heat radiation performance). That is, as shown in FIG. 33A, since
the step surfaces 2c, 9c of the insertion holes 2a, 9a are provided
so as not to close a through hole 34a of the tube 8, respectively.
Furthermore, the cooling device 1 can be temporarily assembled only
by inserting the ends of the tubes 8 into the insertion holes 2a,
9a of the refrigerant container 2 and the header tank 9 without a
complex (expensive) jig. Therefore, the cooling device 1
temporarily assembled can be readily integrally brazed, without
using complex (expensive) brazing jig.
[0102] In the above-described fifteenth embodiment, the insertion
hole 2a, 9a may be provided in the plate 6B or may be provided in
the intermediate plate 6C. Alternatively, a step portion for
regulating an insertion length of each tube 8 can be provided in
the tubes 8 similarly to the above-described seventh embodiment
(FIG. 19), while the refrigerant passage in each tube 8 is not
closed. Even in this case, the insertion length of the tubes 8
inserted into the refrigerant container 2 or inserted into the
header tank 9 can be suitably regulated.
[0103] Although the present invention has been fully described in
connection with the preferred embodiments thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications will become apparent to those skilled in the
art.
[0104] For example, in the above-described embodiments, as shown in
FIG. 38, plate fins 14 may be used as the heat radiation fins 10
described in the above embodiments.
[0105] Further, the plural embodiments described above may be
suitably used by combination.
[0106] Such changes and modifications are to be understood as being
within the scope of the present invention as defined by the
appended claims.
* * * * *