U.S. patent application number 09/977748 was filed with the patent office on 2003-04-17 for non-prismatic heat exchanger construction.
Invention is credited to Dierbeck, Robert F..
Application Number | 20030070788 09/977748 |
Document ID | / |
Family ID | 25525465 |
Filed Date | 2003-04-17 |
United States Patent
Application |
20030070788 |
Kind Code |
A1 |
Dierbeck, Robert F. |
April 17, 2003 |
Non-prismatic heat exchanger construction
Abstract
A non-prismatic heat exchanger with a modular construction for
use with an engine which utilizes a coolant fluid. The heat
exchanger includes a pair of unitary, non-prismatic-shaped headers
spaced from one another and connected by a plurality of unitary,
extruded heat exchanger modules. The headers and modules enclose a
rotary fan within the interior of the heat exchanger. The fan is
mechanically driven by the engine to draw cooling air into the
interior of the heat exchanger and to concurrently force the
cooling air outwardly between the heat exchanger modules to
thermally contact and remove heat from the heated coolant fluid
flowing through the modules.
Inventors: |
Dierbeck, Robert F.;
(Hartford, WI) |
Correspondence
Address: |
ANDRUS, SCEALES, STARKE & SAWALL, LLP
100 EAST WISCONSIN AVENUE, SUITE 1100
MILWAUKEE
WI
53202
US
|
Family ID: |
25525465 |
Appl. No.: |
09/977748 |
Filed: |
October 15, 2001 |
Current U.S.
Class: |
165/41 ; 165/126;
165/51 |
Current CPC
Class: |
F28D 1/05366 20130101;
F01P 2070/32 20130101; F01P 5/02 20130101; F28D 2001/0273
20130101 |
Class at
Publication: |
165/41 ; 165/51;
165/126 |
International
Class: |
F28F 001/00; F01P
001/00; F24B 001/06; F28F 013/12 |
Claims
I claim:
1. A non-prismatic heat exchanger comprising: a pair of headers
disposed on opposite sides of the heat exchanger, each header
including a body having a curved shape, an inlet on one side of the
body, at least one outlet spaced from the inlet, each body defining
a center opening; a plurality of unitary heat exchange modules
interconnecting and providing fluid communication between the
headers and surrounding the opening in each header to define a
hollow interior within the heat exchanger, each module including at
least one longitudinal throughbore extending the length of the
module and in fluid communication with the headers at each end, and
a plurality of slots defining heat transfer fins extending across
the module perpendicular to the one throughbore; and a rotor
disposed within the hollow interior of the heat exchanger, the fan
including a central shaft rotatably mounted to the headers at each
end and a plurality of vanes connected to the shaft.
2. The heat exchanger of claim 1 wherein the headers are generally
semicircular in shape.
3. The heat exchanger of claim 2 further comprising a panel secured
to opposite ends of each header to enclose the opening in the
headers.
4. The heat exchanger of claim 3 wherein the panel is generally
semicylindrical in shape.
5. The heat exchanger of claim 1 wherein the headers are generally
circular in shape.
6. The heat exchanger of claim 5 further comprising a collar
disposed within the opening of each header and connected to the
header by a number of supports, wherein the central shaft of the
rotor is rotatably mounted to the collar.
7. The heat exchanger of claim 6 wherein the collar and the number
of supports are integrally formed with the headers.
8. The heat exchanger of claim 1 wherein the slots are cut into
opposite faces of each module to define the fins.
9. The heat exchanger of claim 1, wherein the modules are provided
with a plurality of grooves extending along each face of the module
parallel to the throughbores, such that the slots define the
toothed fins.
10. The heat exchanger of claim 9 wherein the grooves are generally
V-shaped.
11. The heat exchanger of claim 9 wherein adjacent modules include
fins that are offset from one another such that fins on one of the
adjacent modules are insertable into the slots on the other of the
adjacent modules.
12. The heat exchanger of claim 2 wherein the headers each include
a pair of semi-circular hollow bodies that are connected by a pair
of header extensions at each end.
13. The heat exchanger of claim 5 wherein the header is formed of a
pair of semi-circular headers secured to one another at opposite
ends.
14. The heat exchanger of claim 1 wherein the vanes are disposed on
the fan along radial lines extending from the shaft.
15. The heat exchanger of claim 1 wherein the vanes are disposed on
the fan in a helical configuration.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to heat exchangers for use in
automobiles, and more specifically to a heat exchanger including a
pair of non-prismatic headers connected by one or more unitary,
extruded heat exchanger modules that enclose a rotatable fan.
BACKGROUND OF THE INVENTION
[0002] In order to reduce the temperature of a coolant flowing out
of an internal combustion engine, such as an automobile engine, a
heat exchanger is utilized. The heat exchanger enables the coolant
to flow through tubes within the heat exchanger that are in thermal
contact with a cooling fluid. The cooling fluid passes around the
tubes of the heat exchanger in order to remove or otherwise
dissipate an amount of heat from the coolant as the coolant flows
through the tubes of the heat exchanger.
[0003] A number of different types of heat exchangers have been
developed for use with automobiles in order to reduce the
temperature of a coolant utilized in the engine. One type of heat
exchanger that has been developed specifically for use with an
automobile engine is a heat exchanger having a generally circular
cross section. Examples of heat exchangers of this type are shown
in Goetz, Jr. U.S. Pat. Nos. 5,078,206 and 5,172,752 and Nakamura
et al. U.S. Pat. No. 4,909,311, each of which are incorporated
herein by reference.
[0004] In the Nakamura et al. '311 patent, a pair of generally
circular headers or tanks are connected by a plurality of tubes
that extend horizontally between the tanks. Sections of corrugated
sheet metal are inserted and secured between adjacent pairs of
tubes to provide increased surface area for the tubes to enhance
the removal of heat from the coolant, e.g. water, flowing between
the tanks through the tubes by the cooling fluid. To circulate the
cooling fluid, the heat exchanger also includes a pair of fans
disposed in the center of each header which draw the cooling fluid,
i.e. air, into the heat exchanger past the corrugated sheet metal
sections and around the tubes to thermally contact the heated water
and remove an amount of heat from the water. The fans then
discharge the heated air through the center section of each header
at opposite ends of the heat exchanger.
[0005] A similar construction for a heat exchanger is found in the
Goetz, Jr. '206 and '752 patents. In each of these patents, the
heat exchanger includes a number of tubes connected between a pair
of circular header tanks located at either end of each tube. The
headers and tubes enclose a fan inside of the tubes between the
headers. The tubes are each wedge-shaped and include a section of
corrugated material, such as sheet metal, disposed between and
contacting each pair of adjacent tubes. The heat exchanger operates
in a manner similar to the Nakamura et al. '311 patent, with the
fan drawing air past the tubes and corrugated material to remove
heat from the coolant within the tubes before expelling the heated
air through an open center section in each header. However, in
these two patents, the tubes are wedge-shaped rather than circular
in order to maximize the surface area available on each tube for
heat transfer from the heated fluid flowing within the tubes to the
air.
[0006] While each of the above patents discloses a heat exchanger
capable of significantly reducing the temperature of coolant
flowing through the tubes of the heat exchanger, the construction
of each of the disclosed heat exchangers is difficult and time
consuming to manufacture due to the number and complexity of
connections that must be made between the respective parts of the
heat exchanger. More specifically, each individual tube and
corrugated section must be welded or otherwise connected to one
another and to the respective headers in order to form each of the
above heat exchangers. Each of these connections requires a
significant amount of time and effort in order to insure that the
connection is made properly in order to prevent leakage of the
coolant from between the tubes and the headers, and to insure
proper thermal contact between the corrugated sections and the
tubes.
[0007] Therefore, it is desirable to develop a non-prismatic, e.g.
cylindrical, heat exchanger which greatly simplifies the number and
types of connections necessary between the tubes and the headers.
Furthermore, the heat exchanger construction should allow for
various configurations of the heat exchanger to be constructed such
that the heat exchanger can be adapted for use with many different
types of internal combination engines other than just automobile
engines.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a
non-prismatic heat exchanger which has a modular construction
adaptable to conform to a variety of types of internal combustion
engines with which the heat exchanger is used.
[0009] It is another object of the invention to provide a
non-prismatic heat exchanger that has a modular construction that
significantly reduces the overall cost of the heat exchanger and
the amount of time necessary for assembling the heat exchanger.
[0010] It is a further object of the invention to provide a
non-prismatic heat exchanger which utilizes a number of integrally
formed heat exchanger modules in its construction.
[0011] The present invention is a non-prismatic heat exchanger
including a pair of headers having an open center section that are
spaced from one another and connected by a plurality of unitary
heat exchanger modules that extend between the headers. Each header
includes a hub disposed within the center section that supports one
end of a rotating shaft of a rotor or fan located between the
headers and enclosed by the heat exchanger modules. The shaft
extends outwardly through the hub on one of the headers and is
connected to a drive means capable of rotating the shaft and fan
within the heat exchanger to force air between the heat exchanger
modules. The air serves as a cooling fluid to remove heat from and
reduce the temperature of a heated coolant flowing through the
headers and heat exchanger modules. The arrangement of the heat
exchanger modules and headers can be readily altered during
construction such that the shape of the heat exchanger can be
adapted for use with the particular engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The following drawing figures illustrate the best mode
currently contemplated of carrying out the invention.
[0013] In the drawings:
[0014] FIG. 1 is an isometric view of a non-prismatic heat
exchanger constructed according to the present invention;
[0015] FIG. 2 is a cross-sectional view taken on line 2-2 of FIG.
1;
[0016] FIG. 3 is a cross-sectional view taken on line 3-3 of FIG.
2;
[0017] FIG. 4 is an enlarged sectional detail taken on line 4-4 of
FIG. 3;
[0018] FIG. 5 is a sectional detail taken on line 5-5 of FIG.
4;
[0019] FIG. 6 is an enlarged sectional detail taken on line 6-6 of
FIG. 3;
[0020] FIG. 7 is an end view of a second embodiment of the heat
exchanger of FIG. 1;
[0021] FIG. 8 is an end view of an alternate header construction
for the heat exchanger of FIG. 1;
[0022] FIGS. 9a-c are end views of alternative modular heat
exchanger tube constructions for use with the heat exchanger of
FIG. 1;
[0023] FIG. 10 is a partial end view of the heat exchanger of FIG.
1 constructed utilizing the heat exchanger tubes of FIG. 9a;
[0024] FIG. 11 is an end view of the heat exchanger of FIG. 1
constructed utilizing the heat exchanger modules of FIG. 9c;
and
[0025] FIG. 12 is a partial sectional view along line 12-12 of FIG.
10;
[0026] FIG. 13 is a partial cross-sectional view along line 13-13
of FIG. 12;
[0027] FIG. 14 is a partial cross-sectional view similar to FIG. 12
showing an offset configuration for the fins; and
[0028] FIG. 15 is a cross-sectional view along line 15-15 of FIG.
14.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] With reference now to the drawing figures in which like
reference numerals designate like parts throughout the disclosure,
a non-prismatic heat exchanger is indicated generally at 20 in FIG.
1. The heat exchanger 20 includes a pair of circular headers 22
disposed at either end of the heat exchanger 20. While the headers
22 are preferably circular in shape, the headers 22 can have any
shape necessary for use with a particular engine type. The headers
22 are connected to one another by a plurality of heat exchanger
modules 24 that extend between the respective headers 22.
[0030] Referring now to FIGS. 1-3, each of the headers 22 includes
a central opening 26 defined by the header 22. To define the
opening 26, the header 22 is formed of a circular inner wall 28
which is joined to a circular outer wall 30 by an outer end wall 32
and an interior side wall 34. The opening 26 is defined by the
circumference of the inner wall 28 which includes a number of
supports 36 that extend into the opening 26 from the inner wall 28.
Each support 36 extends radially inwardly along a diameter line of
the circular inner wall 28 and is used to fix a hub or collar 38
concentrically within the opening 26. Preferably the supports 36
are spaced about equidistant from one another around the
circumference of the inner wall 28. The hub 38 is preferably formed
as a generally cylindrical sleeve defining a central aperture 40
extending through the center of the hub 38.
[0031] Each header 22 also includes a fluid connector 42 secured to
the end wall 32. When the heat exchanger 20 is in use, each fluid
connector 42 is connected to a hose 44 which directs a fluid to be
cooled either into or out of a header 22 through an orifice 46
disposed in the end wall 32 of the header 22.
[0032] As best shown in FIGS. 2 and 3, the interior side wall 34 of
each header 22 serves as a header plate and includes a plurality of
openings 48 which receive opposite ends of each module 24. The
openings 48 enable the modules 24 to be placed in communication
with the interior of each header 22 such that the fluid exiting or
entering the header 22 can also flow through each of the modules
24.
[0033] Referring now to FIGS. 3-6, each of the modules 24 connected
between the headers 22 is a unitarily formed, extruded tube formed
similarly to that disclosed in Dierbeck U.S. Pat. Nos. 5,915,470;
5,383,517; and 5,323,707, which are herein incorporated by
reference. The modules 24 can be formed of any generally rigid,
thermally conductive material, with aluminum being the preferred
material. Each module 24 includes a pair of opposed faces 50 and a
pair of throughbores 52 which extend longitudinally through the
entire module 24 between the faces 50. The number of throughbores
52 in each module 24 can vary depending upon the particular
application for the heat exchanger 20, but preferably, as shown,
two throughbores 52 are present in each module 24.
[0034] Each module 24 also includes a plurality of V-shaped grooves
54 extending along the opposite faces 50 of each tube 24. The
grooves 54 on each face 50 extend parallel to the throughbores 52
and are bounded on opposite ends by a pair of flat end portions 56.
The flat end portions 56 are sized to be able to be inserted
through the openings 48 in the side walls 34. The end portions 56
for each module 24 can then be secured to the side walls 34 in
order to form the exchanger 20 by suitable securing means. A
preferred securing means for use in securing the end portions 56 to
the side walls 34 are welds 58, as shown in FIG. 5.
[0035] Each module 24 also includes a number of slots 60 cut across
each face 50 perpendicular to the grooves 54 and throughbores 52.
The slots 60 do not intersect the throughbores 52 but serve to
define a plurality of laterally extending saw-tooth fins 62 between
each adjacent pair of slots 60. The slots 60 and fins 62 enable a
cooling fluid, such as air, to flow through the slots 60 and past
the fins 62 to thermally contact and remove heat which the module
24 has absorbed from a heated fluid flowing perpendicularly to the
air within the throughbores 52.
[0036] The slots 60 extend along each face 50 between a pair of
uncut sections 64. These sections 64 separate the slots 60 from the
flat end portions 56 and serve to align the respective modules 24
with the headers 22 and with one another during construction of the
heat exchanger 20.
[0037] The configuration of the openings 48 in each side wall 34
enables the modules 24 to be arranged in any pattern to enable the
heat exchanger 20 to be shaped to accommodate the particular space
in which the exchanger is to be positioned. As best shown in FIG.
3, in a preferred embodiment, the openings 48 in the side walls 34
of each header 22 are in a generally circular pattern around each
side wall 34 such that the modules 24 are spaced in a staggered
configuration around each side of the side walls 34. Further, as
necessary, a pair of enlarged width modules 24a are attached
adjacent the top and bottom of each side wall 34 to provide a
generally complete enclosure of the central opening 26 in each
header 22. Alternatively, the enlarged modules 24a could be
replaced with a number of modules 24 positioned in line with one
another. The staggered configuration of the modules 24 and 24a
enables a cooling fluid, such as air, to pass between adjacent
modules 24 and 24a through the slots 60 and between the fins 62 on
each module 24 and 24a. The direction of the flow of the cooling
fluid is indicated by the arrows marked A in FIG. 3.
[0038] Referring now to FIGS. 9-15, three alternative embodiments
for the modules 24 and 24a are illustrated. In FIG. 9a, a module 24
includes V- or U-shaped grooves 66 on opposed faces 50 of the
module 24 that extend parallel to a single throughbore 68 disposed
within the module 24. The U-shaped grooves 66, conjunction with
slots 69 that extend perpendicularly across the grooves 66, define
fins 70 which can be positioned within the U-shaped grooves 66 on
adjacent modules 24 to form the overlapping heat exchanger module
configuration shown in FIG. 10. The fins 70 have a saw toothed
configuration similar to the fins 62 of the previously described
embodiments. However, the more U-shape of the grooves 66, results
in somewhat smaller and narrower teeth 67 defining the fins 70.
This configuration enables a heat exchanger 20 that is constructed
in this manner to be smaller in size than the exchanger 20 shown in
FIGS. 1-3 due to the nesting of the modules 24 within one another.
Further, the effectiveness of the exchanger 20 is not reduced
because a higher amount of turbulence is generated in the flow of
the cooling fluid past the fins 70. This increase is graphically
illustrated in FIGS. 12-15 where the overlap of the fins 70 on
adjacent modules 24 and the flow path of the cooling fluid between
the fins 70 is shown for both aligned (FIGS. 12 and 13) and
staggered (FIGS. 14 and 15) arrangements of the fins 70. In the
arrangement of FIGS. 12 and 13, the fins 70 on adjacent modules 24
are aligned horizontally, but the teeth 67 of one module enter
grooves 66 in the adjacent module and are disposed between the
corresponding teeth 67 defined by such grooves. In the arrangement
of FIGS. 14 and 15, the fins 70 of one module are offset vertically
with respect to the fins 70 of the adjacent module such that the
fins 70 of one module are positioned between the similar fins 70 of
the adjacent module. In this latter arrangement, the teeth 67 on
adjacent modules may be either aligned or offset vertically. The
increase turbulence increases the thermal contact of the cooling
fluid with the module 24 and insures an amount of heat transfer
between the heated fluid flowing within the throughbore 68 and the
cooling fluid comparable to that achieved with the previous
embodiment for the heat exchanger 20.
[0039] A similar configuration for the modules 24 is shown in FIG.
9b in which the U-shaped grooves 66 are cut deeper into the body of
the module 24 in order to increase the surface area available for
heat transfer and to reduce the amount of material the heat must be
transferred through on each module 24. This further increases
through the amount of heat that can be transferred from the heated
fluid in the throughbore 68 to the coolant fluid flowing past the
fins 70.
[0040] A fourth embodiment of the module 24 is shown in FIG. 9c. In
this embodiment, the module 24 includes a number of V- or U-shaped
grooves 66 formed on the opposite faces 50 of the module 24. The
grooves 66 on opposite faces 50 of the module 24 are offset from
one another such that the fins 70 on one face 50 are in alignment
with the grooves 66 on the opposite face 50. This configuration
enables the modules 24 to be positioned with the modules 24 in
either a staggered arrangement similar to FIG. 10, or in an aligned
arrangement as shown in FIG. 11. The arrangement of the modules 24
shown in either FIG. 10 or 11 positions the fins 70 of adjacent
modules 24 such that all laminar flow of the cooling fluid past the
fins 70 is disrupted and made highly turbulent to increase the
thermal contact of the cooling fluid with the fins 70.
[0041] Referring again to FIGS. 1-3, the assembly of the headers 22
and modules 24 encloses a cylindrical fan 72 within the heat
exchanger 20. The fan 72 includes a central shaft 74 that is
rotatably mounted to each hub 38 disposed in the openings 26 in the
headers 22. At one end, the shaft 74 extends through the hub 38 and
is fixedly connected to a pulley 76. The pulley 76 is engaged by a
belt 78 that is driven by a driving means in order to rotate the
pulley 76 and the shaft 74. The driving means can be any suitable
mechanism, such as a motor separate from the engine being cooled,
but is preferably a part of the engine from which the coolant is
flowing to the heat exchanger 20.
[0042] Within the heat exchanger 20, the shaft 74 is connected to a
pair of generally circular rims 80 disposed adjacent each header
22. The rims 80 are held in position on the shaft 74 by a pair of
bands 81 disposed on the shaft 74 against each rim and have a
diameter slightly less than the diameter of the central openings 26
in each header 22. The rims 80 include a number of arc-shaped, open
sections 82 in each rim 80. The sections 82 define a number of arms
84 extending outwardly from the center of each rim 80 in order to
support a ring 86 forming the periphery of each rim 80. A number of
rectangular vanes 88 are connected between the respective rings 86.
The vanes 88 are circumferentially spaced from one another about
the rings 86 and are each positioned along a radial line extending
outwardly from the center of the shaft 74 through the vane 88. The
vanes 88 serve to force the cooling fluid through the slots 60 and
around the fins 62 of each of the respective modules 24 and 24a as
the fan 72 is rotated to thermally contact the cooling fluid with
the heated coolant flowing within each of the modules 24 and 24a.
While the vanes 88 are preferably oriented as described above, the
vanes 88 can be positioned at any angle with respect to the shaft
74 or in any other configuration needed to obtain the desired
volume of air to be moved by the fan 72, such as in a helical or
spiral configuration.
[0043] During operation, the heated coolant from the engine enters
the heat exchanger 20 through a fluid connector 42 on one of the
headers 22. The heated fluid is distributed by the header 22 into
each of the modules 24 and 24a such that the heated fluid flows
through the throughbores 52 in each of the modules 24 and 24a. At
the same time, the belt 78 is driven by the driving means on the
engine in order to rotate the pulley 76 and fixed shaft 74.
Rotation of the shaft 74 also rotates the panels 80 and vanes 88 of
the fan 72 within the interior of the heat exchanger 20. The
rotation of the vanes 88 draws a cooling fluid, i.e., air, into the
interior of the heat exchanger 20 through the central openings 26
in each header 22 as indicated by arrows A in FIGS. 1 and 2. The
air drawn into the heat exchanger through the openings 26 is then
forced out of the exchanger 20 by the rotating vanes 88. In exiting
the heat exchanger 20, the air is forced between the modules 24 and
24a through the slots 60 and around the fins 62 on each face 50 of
the modules 24 and 24a, as indicated by arrows B in FIGS. 1 and 2,
such that the air contacts the slots 60 and fins 62. By contacting
the slots 60 and fins 62, the air absorbs and removes an amount of
heat present in the fins 62 which was thermally transmitted to the
fins 62 from the heated coolant through the body of the module 24.
The air thermally contacts the heated fluid along the entire length
of the module 24 until the heated fluid reaches the opposite header
22. Upon reaching the opposite header 22, the now-cooled coolant
exits the modules 24 and is directed by opposite header 22 into a
fluid connector 42 for recirculation through the hose 44 and back
to the internal combustion engine to provide additional cooling for
the engine.
[0044] While the above description illustrates the best mode
currently contemplated of practicing the invention, other
alternative embodiments of the invention are also contemplated. For
instance, with reference to FIG. 7, each header 22 can be formed as
a semi-circular hollow body 90. The hollow body 90 is formed
similarly to the header 22, including openings 48 for the insertion
of the modules 24 to connect a pair of hollow bodies 90 at opposite
ends of the modules 24. Each hollow body 90 is also connected at
each end to a semi-cylindrical cover plate 92 at opposite ends of
the plate 92. The fan 72 is attached between the holes 38 on each
hollow body 90 and is enclosed by the hollow bodies 90, the modules
24 and the cover plate 92. The cover plate 92 extends continuously
between the respective hollow bodies 90 and serves to direct all of
the air drawn through the central openings 26 by the fan 72,
between the modules 24 extending between the hollow bodies 90 to
obtain enhanced heat reduction in the heated fluid flowing through
the modules 24.
[0045] Furthermore, as best shown in FIG. 8, each of the headers 22
can be formed of a pair of hollow bodies 90 of FIG. 7 joined in
fluid communication and connected directly to one another at
opposite ends, as by welding.
[0046] Various alternatives are contemplated as being within the
scope of the following claims particularly pointing out and
distinctly claiming the subject matter regarded as the
invention.
* * * * *