U.S. patent application number 13/165277 was filed with the patent office on 2012-07-26 for heat exchanger.
This patent application is currently assigned to Benteler Automobiltechnik GmbH. Invention is credited to THOMAS ILGNER, CHRISTOPH LEMPA, ANDREAS ROTH.
Application Number | 20120186780 13/165277 |
Document ID | / |
Family ID | 44546368 |
Filed Date | 2012-07-26 |
United States Patent
Application |
20120186780 |
Kind Code |
A1 |
ILGNER; THOMAS ; et
al. |
July 26, 2012 |
HEAT EXCHANGER
Abstract
A heat exchanger for an internal combustion engine includes a
base tube having opposite ends, and tube plates respectively
provided at the ends of the base tube. A ring embraces the base
tube. The ring is made of sheet metal and has legs extending toward
one another in a V-shaped manner. An end cap is provided in the
region of each tube plate and has a circumferential outwardly
directed rim which is embraced by a tension element and connected
to the ring.
Inventors: |
ILGNER; THOMAS; (Salzkotten,
DE) ; ROTH; ANDREAS; (Willebadessen, DE) ;
LEMPA; CHRISTOPH; (Salzkotten, DE) |
Assignee: |
Benteler Automobiltechnik
GmbH
Paderborn
DE
|
Family ID: |
44546368 |
Appl. No.: |
13/165277 |
Filed: |
June 21, 2011 |
Current U.S.
Class: |
165/76 |
Current CPC
Class: |
F02B 29/045 20130101;
Y02T 10/12 20130101; Y02T 10/146 20130101; F02M 26/29 20160201;
F28F 9/0219 20130101; F28F 2275/08 20130101; F28F 9/00
20130101 |
Class at
Publication: |
165/76 |
International
Class: |
F28F 7/00 20060101
F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 24, 2010 |
DE |
102010025031.7-16 |
Claims
1. A heat exchanger for an internal combustion engine, comprising:
a base tube having opposite ends; tube plates respectively provided
at the ends of the base tube; and a ring embracing the base tube,
said ring being made of sheet metal and having legs extending
toward one another in a V-shaped manner.
2. The heat exchanger of claim 1, wherein the ring has a contour
which follows a contour of the base tube.
3. The heat exchanger of claim 1, wherein at least one of the legs
bears flatly upon the ring.
4. The heat exchanger of claim 1, wherein the ring is arranged
between the tube plates.
5. The heat exchanger of claim 1, wherein the ring has a bridge to
connect first ends of the legs to one another.
6. The heat exchanger of claim 1, wherein the ring has a circular
ring shaped configuration.
7. The heat exchanger of claim 5, wherein the legs have
bridge-distal second ends having flanges pointing away from one
another.
8. The heat exchanger of claim 1, wherein the ring is connected to
the base tube by a material joint.
9. The heat exchanger of claim 1, wherein the ring is formed out of
the base tube.
10. The heat exchanger of claim 1, further comprising an end cap
arranged in a region of one of the tube plates.
11. The heat exchanger of claim 10, wherein the end cap has an
outwardly directed rim.
12. The heat exchanger of claim 11, further comprising a detachable
tension element embracing the rim of the end cap.
13. The heat exchanger of claim 11, further comprising a
circumferential sealing element arranged between the rim and the
ring.
14. The heat exchanger of claim 12, wherein the tension element has
a substantially V-shaped configuration in cross section and has a
free end which grips around one of the legs of the ring and the rim
of the end cap bearing on the other one of the legs.
15. The heat exchanger of claim 12, wherein the tension element has
an open ring shape to define two ends, and further comprising a
detachable connection element to connect the two ends of the
tension element.
16. The heat exchanger of claim 15, wherein the detachable
connection element is configured as a screw fastener whereby
turning of the screw fastener in a first direction decreases a
circumference of the tension element and turning of the screw
fastener in a second direction in opposition to the first direction
decreases the circumference of the tension element.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the priority of German Patent
Application, Serial No. 10 2010 025 031.7, filed Jun. 24, 2010,
pursuant to 35 U.S.C. 119(a)-(d), the content of which is
incorporated herein by reference in its entirety as if fully set
forth herein.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a heat exchanger.
[0003] The following discussion of related art is provided to
assist the reader in understanding the advantages of the invention,
and is not to be construed as an admission that this related art is
prior art to this invention.
[0004] Heat exchangers are used for example to recover heat or to
cool recirculated exhausts of an internal combustion engine. By
recirculating exhaust gas back to the combustion air, the
proportion on nitrogen oxides in the exhaust that are harmful to
the environment is decreased in particular when using lean mixtures
in combination with high combustion temperatures.
[0005] Exhaust gas cooled down by the heat exchanger and fed to the
combustion process reduces the air surplus contained in fresh air
and lowers the combustion temperature at the same time so as to
establish a combustion that contains significantly less pollutants.
The mixture expanded by non-combustible fractions permits a
lowering of the specific fuel combustion in particular in partial
load operation of the motor.
[0006] Exhaust gas contacts a cooling fluid inside the heat
exchangers in the absence of thorough mixture, resulting in an
exchange of a temperature differential between the two fluids. The
efficiency of the heat exchanger is determined by the surface area
available for the temperature exchange. In order to configure the
exchanger surface area as large as possible despite small outer
dimensions, a number of exhaust-conducting tubes are arranged for
example inside the heat exchanger and swept around
circumferentially by the cooling fluid. A base tube is hereby
provided which is connected at each end thereof by a tube plate.
The exhaust-conducting tubes inside the base tube are combined to
form a tube bundle which extends within the base tube between the
confronting tube plates and is connected thereto. The base tube
connected with the tube plates forms a chamber through which the
cooling fluid flows and which are passed by the exhaust via the
tube bundle.
[0007] It would be desirable and advantageous to provide an
improved heat exchanger to obviate prior art shortcomings.
SUMMARY OF THE INVENTION
[0008] According to one aspect of the present invention, a heat
exchanger for an internal combustion engine includes a base tube
having opposite ends, tube plates respectively provided at the ends
of the base tube, and a ring embracing the base tube, the ring
being made of sheet metal and having legs extending toward one
another in a V-shaped manner.
[0009] The ring has a contour which follows a contour of the base
tube that is surrounded by the ring. This results in a lightweight
structure with little material use. Both legs rest with their
respective ends on the base tube, thereby preventing the ring from
tilting.
[0010] According to another advantageous feature of the present
invention, at least one of the legs may bear flatly upon the
ring.
[0011] According to another advantageous feature of the present
invention, the ring may be arranged between the tube plates. By
coupling the heat exchanger with neighboring components via an
additional structural part in the region of the ring, a balanced
securement with respect to weight distribution is attained.
Possible length variations of the heat exchanger as a result of
thermal stress are thus shifted in approximately equal parts to the
right and left sides of the rings so that increased stress of
connecting structures are reduced to only one end of the base
tube.
[0012] According to another advantageous feature of the present
invention, the ring can have a bridge to connect respective ends of
the legs to one another. The presence of the bridge further
distances the legs and provides the V-shaped ring with a flat tip.
The bridge distances the line contact of both legs with the base
tube relative to one another so as to further secure the ring
against tilting on the base tube. Moreover, the bridge reduces the
size compared to a cross sectional shape with pointed end. Although
both legs may have different lengths, an identical configuration is
currently preferred.
[0013] According to another advantageous feature of the present
invention, the ring can have a circular ring shaped configuration.
This simplifies manufacture of the ring. For example roll forming
may produce the circular ring shape as well as also the V-shaped
cross section which in the form of a bent strand is connected to
one another at the respective ends.
[0014] According to another advantageous feature of the present
invention, the legs have bridge-distal ends which can have flanges
that point away from one another. The flanges enable surface
contact of the ring with the base tube to thereby provide the ring
with a cross sectional shape which is suited to the base tube.
Moreover, the section modulus of the ring transversely to its
length axis is increased.
[0015] According to another advantageous feature of the present
invention, the ring may be connected to the base tube by a material
joint. The material joint may be provided in spots or also across
the entire contacting circumference of the ring with the base tube.
The connection may be realized for example by gluing or welding as
well as soldering.
[0016] According to another advantageous feature of the present
invention, the ring may be formed out of the base tube. This can be
realized by providing the circumferential wall surface of the base
tube with a circumferential protrusion so that the inner
circumference of the base tube is enlarged in the region of the
ring. This configuration eliminates the need for a separate
connection between the ring and the base tube. Apart of the saved
connection, the material use is further decreased accompanied with
saving of an additional production of the ring separated from the
base tube.
[0017] According to another advantageous feature of the present
invention, an end cap can be arranged in a region of one of the
tube plates. The end cap may be provided with an outwardly directed
rim which can be embraced by a detachable tension element and
connected to the ring. As a result of its V-shaped cross section,
the ring is thus able to spontaneously center itself in relation to
the tension element.
[0018] The shape of the rim substantially conforms to the
configuration of the legs of the ring. The rim of the end cap
establishes a circumferential flat contact toward the ring.
[0019] The tension element can also have a substantially V-shaped
configuration in cross section and has a free end which grips
around one of the legs of the ring and the rim of the end cap
bearing upon the opposing leg. The tension element may have an open
ring shape to define two ends which are connected with one another
via a detachable connection element. Advantageously, the detachable
connection element may be configured as a screw fastener, whereby a
turning of the screw fastener can decrease or increase the
circumference of the tension element. As the circumference of the
tension element decreases, the V-shaped cross section of the
tension element is pushed over the ring as well as over the rim of
the end cap to press them against one another.
[0020] The tension element is connected with a neighboring
structural part so that the heat exchanger is fixed in place via
the tension element. Loosening the connection element opens the
tension element whereupon the heat exchanger is liberated and can
be removed from its embracement. At the same time, the connection
between the end cap, connected via the ring with the base tube, and
the heat exchanger is no longer effective. This results in a
reduction of labor costs during replacement or maintenance works
because the heat exchanger can be removed and at the same time
opened when the connection element is loosened.
[0021] According to another advantageous feature of the present
invention, a circumferential sealing element may be arranged
between the rim of the end cap and the ring. The sealing element
may be made of permanently elastic material or of metal or a
combination of both. Turning the detachable connection element to
change the circumference of the tension element causes a
compression of the sealing element between one leg of the ring and
the rim of the end cap to thereby increase the sealing action of
the sealing element.
[0022] In accordance with the present invention, a heat exchanger
is realized having a ring which is of simple structure and
lightweight and can be produced in an economical manner. A
configuration in which the ring is simply configured as a
circumferential projection of the base tube is advantageous because
it does not require additional material and respective
manufacturing processes. As a result of the small contact area
between the ring and the base tube, transmission of heat of the
heat exchanger, generated by hot exhaust, to neighboring components
is reduced. Overall, the weight is reduced and the manufacture is
cost-efficient.
BRIEF DESCRIPTION OF THE DRAWING
[0023] Other features and advantages of the present invention will
be more readily apparent upon reading the following description of
currently preferred exemplified embodiments of the invention with
reference to the accompanying drawing, in which:
[0024] FIG. 1 is a side view of an exemplary heat exchanger;
[0025] FIG. 1a is a plan view upon one end of the heat exchanger of
FIG. 1;
[0026] FIG. 2 is a schematic illustration of another embodiment of
a heat exchanger;
[0027] FIG. 2a is a plan view upon one end of the heat exchanger of
FIG. 2;
[0028] FIG. 3 is a schematic illustration of yet another embodiment
of a heat exchanger;
[0029] FIG. 3a is a plan view upon one end of the heat exchanger of
FIG. 3.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0030] Throughout all the figures, same or corresponding elements
may generally be indicated by same reference numerals. These
depicted embodiments are to be understood as illustrative of the
invention and not as limiting in any way. It should also be
understood that the figures are not necessarily to scale and that
the embodiments are sometimes illustrated by graphic symbols,
phantom lines, diagrammatic representations and fragmentary views.
In certain instances, details which are not necessary for an
understanding of the present invention or which render other
details difficult to perceive may have been omitted.
[0031] Turning now to the drawing, and in particular to FIG. 1,
there is shown a side view of an exemplary heat exchanger,
generally designated by reference numeral 1 and including a base
tube 2 having opposite ends, each end being provided with a tube
plate 3. The base tube 2 has a generally cylindrical cross section,
with the tube plates 3 embracing the ends of the base tube 1. The
tube plates 3 are formed with an edge 4 which extends at a right
angle and circumferentially about the tube plates 3. The edge 4 has
an inner circumference which corresponds to an outer circumference
of the base tube 2 so that the tube plates 3 are placed with their
edges 4 over the base tube 2 in a formfitting manner.
[0032] FIG. 1a is a plan view upon one end of the heat exchanger 1
to show the respective tube plate 3. It can be seen that the tube
plate 3 has a plurality of openings 5 of circular cross section.
Placed within the openings 5 are individual tubes 6 which jointly
establish within the base tube 2 a tube bundle, which is generally
designated by reference numeral 7 and extends between the tube
plates 3 and which is supported in the opposite openings 5.
[0033] Referring now to FIG. 2, there is shown a schematic
illustration of another embodiment of a heat exchanger in
accordance with the present invention, generally designated by
reference numeral 50. The heat exchanger 50 includes a base tube 20
and a ring 8 which is wrapped around the base tube 20. The ring 8
has two legs 9 which extend towards one another in the shape of a V
to provide the ring 8 with a substantially V-shaped configuration
in cross section. The legs 9 are connected to one another by a
bridge 19 at the outer circumference of the ring 8. Formed on their
bridge-distal ends, the legs 9 are provided with flanges 11,
respectively, which point away from one another. As shown in FIG.
2a, the ring 8 has a circular configuration.
[0034] The ring 8, comprised of the legs 9, bridge 10, and flanges
11, is made from a single metal sheet. The ring 8 is in flat
contact via the flanges 11 with the base tube 20 so that the ring 8
tapers in V-shaped manner towards its outer circumference in a
direction of the bridge 10.
[0035] End caps 12, 13 are arranged in the region of the tube
plates 3, respectively, and have an edge analogous to the tube
plates 3. The end cap 13 includes a circumferential rim 14 which is
directed outwards to provide contact of the end cap 13 with the
neighboring one of the legs 9 of the ring 8. This leg 9 and the rim
14 have corresponding inclinations. The rim 14 and the ring 8 are
both embraced about their circumference by a detachable tension
element 15. A sealing element 16 is arranged between the ring 8 and
the rim 14 of the end cap 13.
[0036] FIG. 3 shows another embodiment of a heat exchanger,
generally designated by reference numeral 50a. In the following
description, parts corresponding with those in FIG. 2 will be
identified by corresponding reference numerals followed by an "a".
In this embodiment, provision is made for a ring 8a which is formed
out of a base tube 20a. The ring 8a thus is configured as a
circumferential projection which protrudes out of a peripheral
surface of the base tube 20a. The ring 8a, like the ring 8 of FIG.
2, has legs 11a extending towards one another in the shape of V and
connected at the outer circumference of the ring 8a by a bridge
10a. The inner circumference of the base tube 20a is enlarged in
the region of the ring 8a, with the wall of the base tube 20a being
deflected outwards.
[0037] In the assembled state of the heat exchangers 50, 50a, the
tension element 15 is guided around the ring 8, 8a which is
connected directly or indirectly with components of a motor vehicle
for example. The tension element 15 also establishes a connection
between the base tube 20, 20a and the end cap 13. For that purpose,
the end cap 13 is provided with the circumferential outwardly
directed rim 14 which is connected via the tension element 15 with
the ring 8, 8a. The sealing element 16 is placed between the ring
8, 8a and the rim 14 of the end cap 3.
[0038] During operation, hot exhaust flows for example through the
heat exchanges 1, 50, 50a within the tubes 6 of the tube bundle 7.
Supply of exhaust to and discharge of exhaust from the tube bundle
7 is realized via the end caps 12, 13. A cooling fluid flows via a
inlet as well as an outlet through a chamber as formed by the base
tube 2, 20, 20a and the tube plates 3 and sweeps about the
individual tubes 6, using appropriate baffles (not shown) for
example. The cooling fluid is provided for a heat exchange with the
exhaust to cool the exhaust for example. The surface area formed by
the tubes 6 is large and effects a continuous equalization of the
temperature differentials between the exhaust and the cooling fluid
flowing within the heat exchanger 1, 50, 50a.
[0039] While the invention has been illustrated and described in
connection with currently preferred embodiments shown and described
in detail, it is not intended to be limited to the details shown
since various modifications and structural changes may be made
without departing in any way from the spirit and scope of the
present invention. The embodiments were chosen and described in
order to explain the principles of the invention and practical
application to thereby enable a person skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated. For
example, a heat exchanger according to the present invention can be
used for various applications. In addition to cooling a fluid, a
heat exchanger according to the present invention may be used for
recovery of heat or for heating purposes.
[0040] What is claimed as new and desired to be protected by
Letters Patent is set forth in the appended claims and includes
equivalents of the elements recited therein:
* * * * *