U.S. patent application number 10/575893 was filed with the patent office on 2007-02-08 for heat exchanger, in particular for motor vehicles.
This patent application is currently assigned to BEHR GmbH & CO. KG. Invention is credited to Claus Augenstein, Karsten Emrich, Daniel Hendrix, Frank Von Lutzau.
Application Number | 20070029076 10/575893 |
Document ID | / |
Family ID | 34428512 |
Filed Date | 2007-02-08 |
United States Patent
Application |
20070029076 |
Kind Code |
A1 |
Augenstein; Claus ; et
al. |
February 8, 2007 |
Heat exchanger, in particular for motor vehicles
Abstract
The invention relates to a heat exchanger, in particular for
motor vehicles, for a first gaseous flow medium and a second
gaseous flow medium. Said heat exchanger comprises a tube bundle
containing a plurality of tubes, a first tube base and a second
tube base, a housing, in addition to an inlet connection and an
outlet connection for the gaseous medium. The tubes comprise tube
ends, which are held and sealed by the tube bases and the housing
is connected on one side to the tube bases, forming a cooling
chamber for the liquid flow medium and on its end face to the inlet
and outlet connections.
Inventors: |
Augenstein; Claus;
(Gerlingen, DE) ; Emrich; Karsten; (Stuttgart,
DE) ; Hendrix; Daniel; (Stuttgart, DE) ; Von
Lutzau; Frank; (Berglen, DE) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
BEHR GmbH & CO. KG
|
Family ID: |
34428512 |
Appl. No.: |
10/575893 |
Filed: |
September 15, 2004 |
PCT Filed: |
September 15, 2004 |
PCT NO: |
PCT/EP04/10315 |
371 Date: |
April 14, 2006 |
Current U.S.
Class: |
165/158 |
Current CPC
Class: |
F28F 9/16 20130101; F28F
2255/00 20130101; F28D 7/1684 20130101; F28F 7/02 20130101; F28D
2021/0082 20130101; F28F 21/084 20130101 |
Class at
Publication: |
165/158 |
International
Class: |
F28F 9/02 20060101
F28F009/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 17, 2003 |
DE |
10349140.6 |
Claims
1. A heat exchanger, in particular for motor vehicles, for a first
flow medium and a second flow medium, having a tube bundle which
includes a multiplicity of tubes, a first tube plate and a second
tube plate, a housing and inlet and outlet connection pieces for
the first flow medium, the tubes having tube ends which are held
and sealed in the tube plates, and the housing being connected on
the one hand to the tube plates so as to form a cooling chamber for
the second flow medium and on the other hand at the end sides to
the inlet and outlet connection pieces characterized in that the
first tube plate and the tubes are formed integrally.
2. The heat exchanger as claimed in claim 1, wherein the first tube
plate, the tubes and the housing are formed integrally.
3. The heat exchanger as claimed in claim 1, wherein the integrally
formed parts are produced by impact extrusion.
4. The heat exchanger as claimed in claim 1, wherein the integrally
formed parts are produced by impact extrusion, are preferably
produced from an aluminum extrusion alloy.
5. The heat exchanger as claimed in claim 1 wherein the cross
section of the tubes is round, rectangular or polygonal.
6. The heat exchanger as claimed in claim 1, wherein a rounded
transition region is provided between the tubes and the first tube
plate, in particular on the outer side of the tubes.
7. The heat exchanger as claimed in claim 1, wherein the tubes have
fins or turbulence generators on their inner and/or outer side in
order to improve the heat transfer.
8. The heat exchanger as claimed in claim 1, wherein the inlet and
outlet connection pieces and the tubes of the tube bundle are
arranged aligned with one another.
9. The heat exchanger as claimed in claim 1, wherein the inlet and
outlet connection pieces, the second tube plate and/or the housing
are cohesively joined to the integral, impact-extruded part.
10. The heat exchanger as claimed in claim 1, wherein the housing
has an inlet opening and an outlet opening for the liquid flow
medium.
11. The heat exchanger as claimed in claim 1, wherein charge air
can flow through the tubes and coolant for an internal combustion
engine of a motor vehicle can flow through the housing.
12. The heat exchanger as claimed in claim 1, wherein the first
medium is a liquid or gaseous medium.
13. The heat exchanger as claimed in claim 1, wherein the second
medium is a liquid or gaseous medium.
14. The use of the heat exchanger as claimed in claim 1 as a
primary cooler or intercooler or cooler for the charge air or the
exhaust gas of an internal combustion engine of a motor vehicle.
Description
[0001] The invention relates to a heat exchanger, in particular for
motor vehicles, for a first and a second flow medium, in particular
as described in the preamble of patent claim 1.
[0002] To increase their power, internal combustion engines for
motor vehicles are supercharged, the charge air, after it has been
compressed in the charger, being cooled by a charge-air cooler in
order to increase the delivery. The trend in modern internal
combustion engines is toward higher powers and therefore also
toward higher charge pressures, which is made possible in
particular by improved chargers, for example what are known as VTG
(variable turbine geometry) chargers. In some cases, two-stage
supercharging is also carried out, in which case intercooling of
the charge air is provided for between the two stages. Accordingly,
charge-air systems of this type require a charge-air intercooler.
The boosted supercharging results in higher charge-air
temperatures, which can no longer be dealt with using conventional
charge-air coolers. Known charge-air coolers in some cases have
plastic collection headers, but these can only be used up to
temperatures of approx. 200 degrees Celsius. Above this temperature
threshold up to approximately 260 to 270 degrees Celsius, aluminum
collection headers, which are more thermally stable, are used for
charge-air coolers. If it is desired to continue to use these
conventional charge-air coolers, i.e. at higher charge pressures
and charge-air temperatures, it is necessary to include a primary
cooler, i.e. the charge air is cooled in two stages, specifically
to preferably below approximately 260 degrees, by the primary
cooler. The latter therefore has to be particularly thermally
stable.
[0003] The charge air in the charge-air cooler of motor vehicles is
generally cooled by ambient air, in which case the charge-air
cooler is arranged in the front engine compartment of the motor
vehicle in the region of a coolant/air radiator. In some cases,
however, liquid-cooled charge-air coolers are also used, in which
the coolant from the engine cooling circuit cools the charge air.
One drawback of known charge-air coolers (cf. DE-A 199 53 787 and
DE-A 199 53 785) is the diversion of the charge air into the air
headers, which leads to a pressure loss. Other designs, for example
plate or stacked plate heat exchangers as described in DE-A 195 11
991, have an increased pressure loss on account of the double
diversion of the charge air through 90 degrees.
[0004] Designs in which the pressure loss on the primary side has
been reduced by avoiding diversions are known from the field of
exhaust-gas heat exchangers, for example from DE-A 199 07 163 in
the name of the Applicant or WO 00/26514. These heat exchangers
each have tube bundles, tube plates, housings and exhaust-gas
connection pieces, which are welded or soldered to one another.
This involves a large number of parts and a large number of
manufacturing steps, i.e. entails increased production costs.
[0005] It is an object of the present invention to provide a heat
exchanger of the type described in the introduction which is
thermally stable up to approximately 300 degrees Celsius and
possibly even above and has a preferably relatively low pressure
drop on the gas side, and which can also preferably be produced at
low cost.
[0006] This object is achieved by the features of patent claim 1.
According to the invention, it is provided that the tube bundle and
one of the two tube plates are formed integrally and can be
produced by the impact extrusion process which is known per se.
Impact extrusion is a known technology related to other forms of
extrusion, in which a billet is forced through a shaping tool (die)
(cf. Dubbel, Taschenbuch fur den Maschinenbau [Mechanical
Engineering Handbook], 20th edition, p. 30). The material used is
preferably an aluminum extrusion alloy which is especially suitable
for impact extrusion. The product produced by impact extrusion in
this way is a finished tube plate which is seamlessly and
integrally adjoined by all the tubes of the tube bundle. This has
the advantage that firstly there is no need for separate production
of the tube plate and the tubes and secondly the complex joining of
tubes and tube plates, for example by welding or soldering, is
eliminated. This considerably reduces production costs. The
remaining parts, such as the second tube plate, the housing and the
connection pieces, consist of aluminum materials and are joined to
the impact-extruded part in a conventional way, for example by
soldering or welding. A further advantage is that it is possible to
produce any desired tube cross section, whether round or polygonal,
by impact extrusion. A further advantage is that the tubes of the
tube bundle can be produced in any desired length and wall
thickness. The thermal stability is also achieved by a low-stress
geometry of the all-aluminum heat exchanger according to the
invention.
[0007] According to an advantageous configuration of the invention,
the housing can also be produced by impact extrusion, i.e. in a
single operation with the tube plate and the tube bundle. This has
the advantage of further simplifying production and reducing the
costs of the heat exchanger according to the invention. To complete
the heat exchanger, it is merely necessary for the second tube
plate and the connection pieces to be joined to the impact-extruded
part.
[0008] According to an advantageous configuration of the invention,
the transition region between the tubes and the tube plates is
configured to be round, i.e. provided with a radius. This has the
advantage of an increased strength as a result of a favorable grain
profile and of improving the flow properties of the material. The
transition radius is preferably arranged on the outer side of the
tube, but may also be provided in the inflow region of the tube at
the tube plate. The latter option would further reduce the pressure
drop on the primary side.
[0009] According to a further advantageous configuration of the
invention, the heat exchanger according to the invention is used as
charge-air cooler for internal combustion engines of motor
vehicles, specifically as a primary cooler or intercooler of a
supercharging system. This creates an inexpensive solution which
allows effective cooling of the charge air even at high
supercharging pressures and correspondingly high temperatures and
at the same time allows conventional charge-air coolers to continue
to be used.
[0010] Exemplary embodiments of the invention are illustrated in
the drawing and described in more detail in the text which follows,
in which:
[0011] FIG. 1 shows a first exemplary embodiment of the invention
with impact-extruded tube plate and tube bundle, and
[0012] FIG. 2 shows a second exemplary embodiment of the invention
with impact-extruded tube plate, tube bundle and housing.
[0013] FIG. 1 shows an exploded view of a charge-air cooler 1 for
an internal combustion engine (not illustrated) of a motor vehicle.
The charge-air cooler 1 comprises the following parts, illustrated
from left to right in the drawing: an inlet connection piece 2, a
tube bundle 3 with tube plate 4, a cylindrical housing 5 formed as
a housing sleeve, and an outlet connection piece 6. The tube bundle
3 comprises a multiplicity of tubes 3a which are formed integrally
with the tube plate 4 and each have a rectangular cross section of
flow 3b. The tube plate 4 and the adjoining tubes 3a are produced
by impact extrusion, i.e. a known process related to other forms of
extrusion. The starting material used is an aluminum extrusion
alloy, which is forced through a die (not shown) having the
geometry and arrangement of the tubes 3a. The cross section of the
tubes 3a and their length and wall thickness can be selected as
desired on account of the impact-extrusion process and the
corresponding die. The tubes 3a are therefore fixedly and tightly
connected to the tube plate 4 and fundamentally require no further
treatment. The tube bundle 3 has an end side 3c which faces away
from the tube plate 4 and is provided in a conventional way with a
second tube plate (not illustrated). All the parts, which
preferably consist of aluminum alloys, are soldered together to
form a complete heat exchanger. On its circumference, the housing
sleeve 5 has an inlet connection piece 7 and, diagonally opposite
the latter, an outlet connection piece 8, so that a cooling chamber
9, through which the coolant of an engine cooling circuit (not
shown) can flow, is formed between the two tube plates and the
housing sleeve 5. The coolant therefore flows between the tubes 3a
and around the tube bundle 3. The hot charge air, illustrated by an
arrow LL, enters through the inlet connection piece 2, which is of
diffusor-like design, so that the charge air is distributed
uniformly over the area of the tube plate 4 and the individual tube
cross sections 3b. The charge air flows through all the tubes 3a of
the tube bundle 3 and leaves the tube bundle 3 on the opposite side
3c by entering the outlet connection piece 6. The fully assembled
charge-air cooler 1 is inserted into a charge-air line (not shown),
which is connected flush to the inlet connection piece 2 and the
outlet connection piece 6. Therefore, the charge air flows through
the charge-air cooler 1 in a straight line, i.e. without any
diversions, which leads to a low pressure loss.
[0014] FIG. 2 shows a further exemplary embodiment of the
invention, namely a charge-air cooler 10 with a housing 11 which
has been produced integrally with a tube plate 12 by impact
extrusion, a tube bundle (which is not visible), represented by one
tube 13 portrayed by dashed lines, being formed integrally with the
tube plate 12 and likewise having been produced by impact
extrusion. In this exemplary embodiment, therefore, three
components or modules, namely tube bundle, tube plate and housing,
have been produced integrally in one process step by impact
extrusion. A conventionally manufactured tube plate 14 is attached
to the downstream end (not visible) of the tube bundle 13 and is
joined both to the tubes 13 and to the housing 14, so as to form a
cooling chamber for the coolant within the housing 11. As in the
exemplary embodiment shown in FIG. 1, an inlet connection piece 15
and an outlet connection piece 16, which are joined to the housing
sleeve 11, are fitted into the inlet and outlet ends of the housing
11. All the parts consist of aluminum alloys and are preferably
soldered together.
[0015] The charge-air coolers 1, 10 shown in FIG. 1 and FIG. 2 are
preferably used as a primary cooler or intercooler in a
supercharging system for an internal combustion engine. Both
charge-air coolers are all-aluminum coolers and are therefore able
to withstand charge-air temperatures of up to over 300 degrees
Celsius, which is also achieved by a stress-optimized design. In
the case of primary cooling, the charge air is precooled to approx.
260 degrees and can then be fed to a conventional charge-air cooler
in order to be cooled further.
* * * * *