U.S. patent application number 14/039052 was filed with the patent office on 2014-04-03 for heat exchanger.
This patent application is currently assigned to Behr GmbH & Co., KG. The applicant listed for this patent is Behr GmbH & Co., KG. Invention is credited to Nikolaus DAUBITZER, Anton KIERIG, Michael MOSER, Heiko NEFF, Dominique RAIBLE, Thomas SCHIEHLEN, Caroline SCHMID, Holger SCHROTH.
Application Number | 20140090812 14/039052 |
Document ID | / |
Family ID | 50383126 |
Filed Date | 2014-04-03 |
United States Patent
Application |
20140090812 |
Kind Code |
A1 |
SCHMID; Caroline ; et
al. |
April 3, 2014 |
HEAT EXCHANGER
Abstract
Heat exchanger having a first collecting box and having a second
collecting box, having at least one tube arranged between the two
collecting boxes, wherein a fluid inlet and a fluid outlet are
provided which are arranged individually on in each case one of the
collecting boxes or on a single one of the collecting boxes,
wherein the tube is received at the ends in an opening in in each
case one of the collecting boxes and is in fluid communication with
the collecting boxes, wherein the opening is surrounded by an
opening edge whose contour corresponds to the outer contour of the
tube, and in that the opening is designed such that the opening
cross section narrows toward the interior of the collecting box and
the tube can be inserted, under preload at the circumference, into
the opening.
Inventors: |
SCHMID; Caroline;
(Stuttgart, DE) ; MOSER; Michael; (Rainau, DE)
; DAUBITZER; Nikolaus; (Stuttgart, DE) ; SCHROTH;
Holger; (Maulbronn, DE) ; NEFF; Heiko;
(Auenwald, DE) ; RAIBLE; Dominique; (Rottenburg,
DE) ; KIERIG; Anton; (Stuttgart, DE) ;
SCHIEHLEN; Thomas; (Altheim, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Behr GmbH & Co., KG |
Stuttgart |
|
DE |
|
|
Assignee: |
Behr GmbH & Co., KG
Stuttgart
DE
|
Family ID: |
50383126 |
Appl. No.: |
14/039052 |
Filed: |
September 27, 2013 |
Current U.S.
Class: |
165/104.19 |
Current CPC
Class: |
F28F 1/02 20130101; F28F
1/022 20130101; Y02E 60/10 20130101; F28F 1/00 20130101; H01M
10/625 20150401; F28D 2021/0043 20130101; F28F 9/162 20130101 |
Class at
Publication: |
165/104.19 |
International
Class: |
F28F 1/00 20060101
F28F001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2012 |
DE |
10 2012 217 870.8 |
Claims
1. Heat exchanger having a first collecting box and having a second
collecting box, having at least one tube arranged between the two
collecting boxes, wherein a fluid inlet and a fluid outlet are
provided which are arranged individually on in each case one of the
collecting boxes or on a single one of the collecting boxes,
wherein the tube is received at the ends in an opening in in each
case one of the collecting boxes and is in fluid communication with
the collecting boxes, wherein the opening is surrounded by an
opening edge whose contour corresponds to the outer contour of the
tube, and in the opening is designed such that the opening cross
section narrows toward the interior of the collecting box and the
tube can be inserted, under preload at the circumference, into the
opening.
2. Heat exchanger according to claim 1, wherein the tube is in the
form of a flat tube.
3. Heat exchanger according to claim 1, wherein the inner contour
of the opening can be deformed as a result of the tube being pushed
in.
4. Heat exchanger according to claim 1, wherein, in the assembled
state, a groove which is accessible from outside the collecting box
is formed between the tube and the opening edge.
5. Heat exchanger according to claim 1, wherein the tube and the
collecting boxes can be adhesively bonded and/or welded and/or
pressed together and/or insert-molded with one another.
6. Heat exchanger according to claim 1, wherein at least one of the
collecting boxes is of multi-part form and has a box opening, the
latter being closable by means of a cover, and has a tube plate
with at least one opening for receiving a tube wherein the box
opening is arranged opposite the tube plate.
7. Heat exchanger according to claim 1, wherein the heat exchanger
has a multiplicity of tubes which run parallel to and spaced apart
from one another.
8. Heat exchanger according to claim 7, wherein the tubes lie in a
common plane and/or lie offset with respect to one another in
multiple planes.
9. Heat exchanger (1) according to claim 7, wherein an areal panel
is mounted onto the tubes, by means of which panel said tubes are
connected to one another.
10. Heat exchanger according to claim 1, wherein the fluid inlet
and the fluid outlet are arranged on the same collecting box,
wherein said collecting box has a partition which divides the
internal volume of the collecting box into two chambers, and the
fluid inlet is in fluid communication with one of the chambers and
the fluid outlet is in fluid communication with the other chamber.
Description
TECHNICAL FIELD
[0001] Heat exchanger having a first collecting box and having a
second collecting box, having at least one tube arranged between
the two collecting boxes, wherein a fluid inlet and a fluid outlet
are provided which are arranged individually on in each case one of
the collecting boxes or on a single one of the collecting boxes,
wherein the tube is received at the ends in an opening in in each
case one of the collecting boxes and is in fluid communication with
the collecting boxes.
PRIOR ART
[0002] In electric vehicles, energy stores are used for operating
an electric motor. As energy stores, use is often made of storage
batteries based on lithium-ion technology, or of nickel-metal
hybrid storage batteries. Alternatively, use is also made of
high-performance capacitors, so-called super-caps.
[0003] In the case of all of the energy stores mentioned, an
intense generation of heat occurs during operation, in particular
during fast charging and discharging of the energy stores.
[0004] Temperatures of approximately 50.degree. C. and higher may
however damage the energy stores and significantly reduce the
service life thereof. Likewise, excessively low temperatures cause
lasting damage to the energy stores.
[0005] To maintain the performance of the energy stores, the
temperature of these must therefore be actively controlled. Periods
where cooling is required are more prevalent by far. The cooling
may be realized for example by the introduction of heat exchangers
through which fluid flows. In solutions according to the prior art,
the heat exchangers are often elements through which fluid flows
and which have, between two areal cover panels, one or more fluid
ducts through which a fluid can flow.
[0006] It is advantageous here for all of the cells of the energy
stores to be kept at a uniform temperature level. Likewise, intense
temperature gradients within the cells should be avoided.
[0007] The panels of the heat exchangers can be traversed by a flow
of a cold fluid during cooling, though they may also be traversed
by a flow of a warm fluid for the purpose of heating.
[0008] To attain the highest possible energy efficiency, in
particular in electric vehicles, a design which is optimized as far
as possible with regard to weight is advantageous.
[0009] In the prior art, solutions are described which use heat
exchangers manufactured from metallic materials. Such a solution is
disclosed for example by the utility model DE 20 2012 102 349
U1.
[0010] A disadvantage of the solutions according to the prior art
is in particular that the heat exchangers are often constructed
entirely from aluminum. These are considerably heavier in relation
to designs composed of plastic or of a mixture of aluminum and
plastic. Furthermore, the assembly outlay is greater in the case of
a heat exchanger manufactured entirely from metallic materials.
PRESENTATION OF THE INVENTION, PROBLEM, SOLUTION, ADVANTAGES
[0011] It is therefore the object of the present invention to
provide a heat exchanger which has a weight-optimized design and
the production of which is simple and inexpensive.
[0012] The object of the present invention is achieved by means of
a heat exchanger having the features of claim 1.
[0013] An exemplary embodiment of the invention concerns a heat
exchanger having a first collecting box and having a second
collecting box, having at least one tube arranged between the two
collecting boxes, wherein a fluid inlet and a fluid outlet are
provided which are arranged individually on in each case one of the
collecting boxes or on a single one of the collecting boxes,
wherein the tube is received at the ends in an opening in in each
case one of the collecting boxes and is in fluid communication with
the collecting boxes, wherein the opening is surrounded by an
opening edge whose contour corresponds to the outer contour of the
tube, and wherein the opening is designed such that the opening
cross section narrows toward the interior of the collecting box and
the tube can be inserted, under preload at the circumference, into
the opening.
[0014] In one exemplary embodiment, the heat exchanger according to
the invention serves for controlling the temperature of an energy
store.
[0015] The heat exchanger can be traversed by a flow of a fluid by
means of which cooling or heating can be effected depending on the
temperature of the fluid relative to the surroundings. For this
purpose, the tubes must be connected to the collecting boxes in a
fluid-tight manner. Owing to the configuration of the opening with
an opening cross section smaller than the width of the tube, a
press fit is generated between the tube and the collecting box,
whereby the tube is fixed in the collecting box in a fluid-tight
manner.
[0016] In one advantageous embodiment of the invention, it may be
provided that the tube is in the form of a flat tube.
[0017] It is also preferable for the inner contour of the opening
to be able to be deformed as a result of the tube being pushed
in.
[0018] As a result of the deformation generated as a result of the
tube being pushed in, the tube is acted on by forces which fix the
tube in the collecting box. Said forces are generated by the forced
deformation of the material of the collecting boxes. The more the
material opposes a deformation, or the greater the amount of
material that is deformed as a result of the pushing-in process,
the greater are the forces that act on the tube.
[0019] A heat exchanger with insertable tubes which are fixed in
the collecting box by means of a press fit is particularly simple
to produce. Furthermore, the number of reworking steps is reduced
considerably in relation to a conventional heat exchanger.
[0020] In a further exemplary embodiment of the invention, it may
be provided that, in the assembled state, a groove which is
accessible from outside the collecting box is formed between the
tube and the opening edge.
[0021] The groove that is formed between the tube and the opening
edge of the collecting box serves for receiving an adhesive, for
example. The groove that is generated is open to the outside, away
from the collecting box, such that an adhesive can be introduced
into the groove from there. Here, the groove is formed in a fully
encircling manner around the tube.
[0022] In this way, the tube can be fixed in its position within
the collecting boxes not only by the press fit but also by means of
an adhesive. Here, the adhesive is isolated from the fluid flowing
through the heat exchanger. This is advantageous in particular
because the adhesive need not be configured to be resistant to any
corrosive properties of the fluid.
[0023] A preferred exemplary embodiment of the invention is
characterized in that the tube and the collecting boxes can be
adhesively bonded and/or welded and/or pressed together and/or
insert-molded with one another.
[0024] The tube is fixed in the collecting box with a press fit
simply as a result of it being inserted into the openings of the
collecting boxes, which must be performed with the exertion of a
certain insertion force. Furthermore, the tube may also be welded
into the collecting box or adhesively bonded to said collecting
box. The selection of the connecting means should be made for
example depending on the material pairing that is present.
[0025] Furthermore, it may be expedient for at least one of the
collecting boxes to be of multi-part form and to have a box
opening, the latter being closable by means of a cover, and to have
a tube plate with at least one opening for receiving a tube,
wherein the box opening is arranged opposite the tube plate.
[0026] Using injection molding processes, a multi-part collecting
box is considerably easier to produce than a unipartite collecting
box of complex shape.
[0027] In a particularly expedient exemplary embodiment, it may be
provided that the heat exchanger has a multiplicity of tubes which
run parallel to and spaced apart from one another.
[0028] By means of a multiplicity of tubes, it is possible for the
surface area over which heat is transferred by the heat exchanger
to be considerably increased in size. Furthermore, by means of the
arrangement of multiple tubes, it is possible to realize a
throughflow configuration in which the fluid flows through one
proportion of the tubes from the first collecting box into the
second collecting box and is diverted in the second collecting box
so as to flow back into the first collecting box again through
another proportion of the tubes. Such a throughflow configuration
has the effect that the fluid is subjected to a longer period of
contact with the heat transfer surfaces within the heat
exchanger.
[0029] It may also be advantageous for the tubes to lie in a common
plane and/or to lie offset with respect to one another in multiple
planes.
[0030] For example, it is possible here for the tubes to lie
adjacent one another in parallel in one plane, such that the
central axis of the tubes, which runs along the throughflow
direction, lies on a common plane. It is alternatively also
conceivable for the central axes of one proportion of the tubes to
lie on a common plane and for the central axes of another
proportion to lie on another plane. It is advantageous for all of
the tubes to lie parallel to one another, regardless of which plane
they are assigned to.
[0031] In one preferred embodiment, it is advantageous for the
tubes to be connected to one another by an areal panel.
[0032] In this context, "connected to one another" means both
mechanically and also thermally connected to one another.
[0033] As a result of the arrangement of the tubes in a common
plane, the individual tubes can be connected in a particularly
simple manner by means of an areal panel, such as a panel with good
heat-conducting properties, composed for example of aluminum. This
increases considerably the surface area over which heat can be
transferred.
[0034] With corresponding configuration of the areal panel, it is
also possible for tubes in different planes to be connected to one
another in order to increase the heat transfer area.
[0035] A further preferred exemplary embodiment is characterized in
that the fluid inlet and the fluid outlet are arranged on the same
collecting box, wherein said collecting box has a partition which
divides the internal volume of the collecting box into two
chambers, and the fluid inlet is in fluid communication with one of
the chambers and the fluid outlet is in fluid communication with
the other chamber.
[0036] By means of the arrangement of the fluid inlet and of the
fluid outlet in only one collecting box and also the division of
the internal volume of said collecting box into two chambers, the
heat exchanger can be traversed by flow as follows. The fluid flows
via the fluid inlet into the first chamber of the first collecting
box and flows from there via one proportion of the tubes into the
second collecting box. The second collecting box does not have a
partition and serves for diverting the fluid into the other
proportion of the tubes. The fluid flows via said other proportion
of the tubes back into the second chamber of the first collecting
box, and flows out of the heat exchanger through the fluid
outlet.
[0037] Advantageous refinements of the present invention are
described in the subclaims and in the following description of the
figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] The invention will be explained in detail below on the basis
of exemplary embodiments and with reference to the drawings, in
which:
[0039] FIG. 1 shows a perspective view of a heat exchanger
according to the invention, having two opposite collecting boxes
and having flat tubes which are situated between said collecting
boxes and which, at the ends, are received in in each case one of
the collecting boxes,
[0040] FIG. 2 shows a detail view of the collecting box which has
the fluid inlet and the fluid outlet, wherein the collecting box is
of multi-part form and is illustrated in its individual parts,
and
[0041] FIG. 3 shows a detail view of the opening in one of the
collecting boxes, in each case one flat tube having been inserted
into said opening.
PREFERRED EMBODIMENT OF THE INVENTION
[0042] FIG. 1 shows a perspective view of a heat exchanger 1. The
heat exchanger 1 is composed substantially of a multiplicity of
flat tubes 6 and of two collecting boxes 2, 3 which have in each
case a multiplicity of openings 7 into which the flat tubes 6 are
inserted. The flat tubes 6 are in fluid communication with the
collecting boxes 2, 3.
[0043] The collecting box 3 shown in FIG. 1 also has a fluid inlet
4 and a fluid outlet 5. Via the fluid inlet 4 and the fluid outlet
5, the heat exchanger 1 is in fluid communication with a fluid
circuit.
[0044] The heat exchanger 1 shown in FIG. 1 has a U-shaped
throughflow configuration. The fluid enters the collecting box 3
via the fluid inlet 4, flows through one proportion of the flat
tubes 6 and passes over into the collecting box 2. There, the fluid
distributes over the entire width of the collecting box 2 and flows
via the remaining flat tubes 6 back into the collecting box 3, and
out of the heat exchanger through the fluid outlet 5. To make said
throughflow configuration possible, the collecting box 3 has, in
its interior, a partition (not shown in FIG. 1) which divides the
collecting box 3 into a left-hand chamber and a right-hand chamber.
This construction will be described in more detail in the further
figures.
[0045] The flat tubes 6 shown in FIG. 1 have substantially two
mutually opposite large surfaces. Said large surfaces are directed
upward and downward in the case of FIG. 1. The two large surfaces
of the flat tubes 6 are connected to one another in each case via
short surfaces. As an alternative to the flat tubes 6 shown here,
the use of conventional tubes with circular or rectangular cross
sections is also conceivable.
[0046] Furthermore, the number of flat tubes 6 is likewise
variable. In the case of a heat exchanger 1 with a U-shaped
throughflow configuration, at least two flat tubes 6 must be
provided in order to form at least one outward flow path between
the collecting boxes 3 and 2 and one return flow path between the
collecting boxes 2 and 3. In the case of a heat exchanger 1 with an
I-shaped throughflow configuration, in each case one of the
collecting boxes 2, 3 would have a fluid inlet, and the other would
have the fluid outlet. In this case, a single flat tube would
suffice.
[0047] The flat tubes 6 of the heat exchanger 1 are all arranged in
a common plane. That is to say the upwardly directed large surface
of the flat tubes lies in a plane with the in each case adjacent
flat tubes 6 of the heat exchanger 1, whereby, in the case of
structurally identical flat tubes 6, the lower large surface of the
flat tubes 6 also lies in a plane. In alternative embodiments, an
offset of the flat tubes in different planes is likewise
conceivable.
[0048] The flat tubes 6, which lie in a plane, of the heat
exchanger 1 have a panel 8 which is mounted onto the flat tubes 6
and which connects the mutually adjacent flat tubes 6 to one
another. Said panel 8 serves substantially for providing a planar
and closed contact surface in order that components to be cooled or
to be heated can be connected to the heat exchanger 1 more
effectively.
[0049] The broader the individual flat tubes 6 are, and the smaller
the spacing between the individual flat tubes 6 is, the less is the
need for a panel 8 of said type. In order that the thermal heat
transfer is as far as possible not impeded, it is advantageous for
the panel 8 to be formed from a material with the best possible
heat conducting properties, for example aluminum or an aluminum
alloy. It is likewise advantageous for the panel 8 to be connected
to the flat tubes 6 as cohesively as possible, such that no
unnecessary air cushions, which would constitute an insulation
layer, are formed between the flat tubes 6 and the panel 8.
[0050] The collecting boxes 2, 3 may be produced either from a
material that exhibits good thermal conductivity, such as a
metallic material, or from a plastic or a fiber-reinforced
plastic.
[0051] The flat tubes 6 are advantageously produced from a material
that exhibits good thermal conductivity, for example aluminum. The
embodiment of the flat tubes 6 is however not restricted to said
material. Alternatively, an embodiment of the flat tubes composed
of a plastic is also conceivable.
[0052] The fluid inlet 4 and the fluid outlet 5 are arranged on the
collecting box 3 such that they point upward, away from the
collecting box 3. This illustration is merely an exemplary
illustration of the fluid inlet 4 and of the fluid outlet 5 and
should in no way be regarded as being of a limiting nature. The
arrangement of the fluid inlet and/or fluid outlet 4, 5 on some
other side surface of the collecting box 3 is likewise conceivable.
The arrangement of the fluid inlet and/or fluid outlet on the
opposite collecting box 2, or the provision of a fluid inlet on one
of the two collecting boxes and the provision of the fluid outlet
on the respective other one of the collecting boxes, is also
conceivable.
[0053] By means of such an arrangement of the fluid inlet and/or
fluid outlet, the heat exchanger would be traversed by flow either
with an I-shaped throughflow configuration or, if a multiplicity of
partitions is arranged within the collecting boxes, with a multiply
diverted flow configuration.
[0054] FIG. 2 shows a detail view of the collecting box 3 of the
heat exchanger 1, as has already been shown in FIG. 1. It can be
seen particularly clearly that the collecting box 3 is of
multi-part construction and is composed of a main body 14 which is
closed off laterally by a cover 10. The main body 14 has both the
fluid inlet 4 and also the fluid outlet 5. The internal volume 15
of the main body 14 is divided into two chambers 11, 12 by a
partition 13. In the exemplary embodiment shown in FIG. 2, the
chamber 11 is in fluid communication with the fluid inlet 4. The
second chamber 12 is in fluid communication with the fluid outlet
5.
[0055] The main body 14 is formed substantially by a box which is
closed on five sides and open on one side. The open side, which can
be closed by means of the cover 10, is situated opposite the side
which has the openings 7 into which the flat tubes 6 are
inserted.
[0056] The production of the collecting box 3 in a multi-part
embodiment is advantageous in particular because the individual
components can be produced more easily, for example by injection
molding techniques. The connection of the main body 14 to the cover
10 is possible through the use of a welding process. Since ideally
both the main body 14 and also the cover 10 are produced from the
same material, this use of a welding process is particularly
advantageous.
[0057] In alternative embodiments, as already indicated with regard
to the description of FIG. 1, a division of a collecting box into
more than two chambers is also conceivable. By means of a division
of the collecting box into more than two chambers, it would be
possible to realize a situation in which the fluid is diverted
multiple times within the heat exchanger 1. This would have the
effect that the fluid covers an altogether longer flow path within
the heat exchanger. This may be advantageous in particular in order
to increase the heat transfer.
[0058] The panel 8 which is shown both in FIG. 1 and also in FIG. 2
serves to provide a closed planar contact surface for the
connection of components to be cooled or to be heated to the heat
exchanger 1. A further advantage of the panel 8 is that the panel 8
can have for example an electrically insulating coating or a foil
applied to it already before an assembly process, which prevents
for example the formation of short circuits between the components
to be cooled or to be heated and the heat exchanger 1.
[0059] The application of a coating to the panel 8 already before
the assembly process has the effect of considerably simplifying the
assembly of the heat exchanger 1, and thus contributes to a
reduction in costs of the production process.
[0060] A particular advantage of a heat exchanger 1 as shown in
FIGS. 1 and 2 is that the overall structural length of the heat
exchanger 1 can be easily adapted at any time through corresponding
variation of the length of the flat tubes 6. It is thus ensured
that, by means of the basic structural form of the heat exchanger
1, it is possible for components of different sizes to be cooled or
heated, without it being necessary to fundamentally change the
construction of the heat exchanger 1.
[0061] FIG. 3 shows a detail view of the connecting point between a
flat tube 21 and a collecting box 20. The flat tube shown in FIG. 3
is divided, in its interior, into multiple chambers 22. The flat
tube 21 likewise has two substantially opposite large surfaces
which are connected to one another at the sides by two short
surfaces. Here, the two large surfaces of the flat tube 21 lie
parallel to the top side and bottom side, respectively, of the
collecting box 20.
[0062] The collecting box 20 has in each case one opening 23 for
each flat tube 21. Said opening 23 has an opening edge 28 which
tapers conically. The opening cross section of the opening 23
narrows toward the internal volume 26 of the collecting box 20 as
viewed from the outer edge 27 of the collecting box 20. Here, the
opening 23 is dimensioned such that the clear width of the opening
cross section of the opening 23 is smaller than the width of the
outer contour of the tube 21.
[0063] This has the effect that the flat tube 21 can be pushed into
the opening 23 of the collecting box 20 only with the exertion of a
certain force. Owing to the opening cross section of the openings
23 being smaller than the cross section of the flat tube 21, a
deformation of the collecting box 20 takes place as the flat tube
is pushed into the opening 23. As a result of such a deformation,
forces are generated which act on the outer surfaces of the flat
tube 21 and which fix the latter in the opening 23 of the
collecting box 20.
[0064] In FIG. 3, the reference sign 25 denotes two regions which
are each deformed as a result of the flat tube 21 being pushed in.
The regions denoted by the reference sign 25 form the location of
the smallest opening cross section of the openings 23. Said regions
simultaneously form the clear width of the openings 23. Said
regions are deformed and displaced by the flat tube 21.
[0065] Said deformed region 25, which in FIG. 3 is illustrated at
the top side and at the bottom side of the flat tube 21, ideally
runs around the entire circumference of the openings 23 in order to
produce an altogether fluid-tight connection between the flat tube
21 and the collecting box.
[0066] As a result of the conical design of the opening edge 28,
there is formed between the flat tube 21 and the collecting box 20
a groove 29 which, in FIG. 3, has a triangular basic shape. Said
groove 29 is open in an outward direction, away from the collecting
box.
[0067] The groove 29, which is formed in an encircling manner
around the entire flat tube 21, serves for example for receiving an
adhesive 24. The flat tube 21 can thus be fixed on the collecting
box 20 not only by the press fit in the opening 23 but also by
means of an adhesive 24. It is advantageous here in particular that
the adhesive 24 is isolated in an effective manner so as to be
prevented from coming into contact with the fluid that flows within
the flat tube 21 or the collecting box 20. In this way, the
adhesive need not be configured so as to be resistant to any
corrosive effects of the fluid or other detrimental influences of
the fluid on the adhesive 24.
* * * * *