U.S. patent application number 11/897319 was filed with the patent office on 2008-03-06 for heat exchanger unit.
Invention is credited to Klaus Beetz, Hans-Peter Drespling.
Application Number | 20080053644 11/897319 |
Document ID | / |
Family ID | 38805644 |
Filed Date | 2008-03-06 |
United States Patent
Application |
20080053644 |
Kind Code |
A1 |
Beetz; Klaus ; et
al. |
March 6, 2008 |
Heat exchanger unit
Abstract
The present invention relates to a heat transfer unit, in
particular a charge air cooler, having a housing in which first
flow channels for a gas to be cooled, and second flow channels for
a cooling medium are situated separately therefrom. It is essential
to the invention here that the first flow channels are made of
hollow metallic bodies, each of which is sheathed with plastic on
their longitudinal ends to form a shared tube bottom, wherein the
second flow channels are bordered by outsides of the hollow
metallic bodies, the two tube bottoms and an inside of the housing
which is made of plastic.
Inventors: |
Beetz; Klaus; (Karlsruhe,
DE) ; Drespling; Hans-Peter; (Heidenheim,
DE) |
Correspondence
Address: |
RADER, FISHMAN & GRAUER PLLC
39533 WOODWARD AVENUE
SUITE 140
BLOOMFIELD HILLS
MI
48304-0610
US
|
Family ID: |
38805644 |
Appl. No.: |
11/897319 |
Filed: |
August 30, 2007 |
Current U.S.
Class: |
165/151 |
Current CPC
Class: |
Y02T 10/12 20130101;
F02B 29/0462 20130101; F02M 26/32 20160201; Y02T 10/146 20130101;
F28F 2255/143 20130101; F28F 9/00 20130101; F28F 21/067 20130101;
F28D 7/1684 20130101; F28D 2021/0082 20130101 |
Class at
Publication: |
165/151 |
International
Class: |
F28D 1/04 20060101
F28D001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2006 |
DE |
DE102006040851.9 |
Claims
1. A heat transfer unit, in particular a charge air cooler, having
a housing in which first flow channels for gas to be cooled and
separate second flow channels for a cooling medium are situated,
wherein the first flow channels are made of hollow metallic bodies
which are sheathed with plastic on each of their longitudinal ends
to form a shared tube bottom, the second flow channels are bordered
by outsides of the hollow metallic bodies, the two tube bottoms and
an inside of the housing which is made of plastic.
2. The heat transfer unit according to claim 1, wherein the housing
comprises the two tube bottoms, two side walls, a cover and a
bottom, whereby the cover and the bottom each have a cooling medium
connection.
3. The heat transfer unit according to claim 1, wherein two side
walls of the housing joining the two tube bottoms to one another
are integrally molded onto the two tube bottoms.
4. The heat transfer unit according to claim 1, wherein two side
walls of the housing joining the two tube bottoms together are
manufactured together with the tube bottoms by injection
molding.
5. The heat transfer unit according to claim 2, wherein the cover
and/or the bottom is/are welded to the remaining housing.
6. The heat transfer unit according to claim 1, wherein at least a
part of the housing is a component of an intake system of an
internal combustion engine.
7. The heat transfer unit according to claim 1, wherein the first
flow channels are made of aluminum.
8. The heat transfer unit according to claim 1, wherein the first
flow channels have a rectangular cross section.
9. The heat transfer unit according to claim 1, wherein the first
flow channels have the same cross section and/or the same
length.
10. The heat transfer unit according to claim 1, wherein heat
transfer elements are arranged inside the hollow bodies of the
first flow channels.
11. The heat transfer unit according to claim 2, wherein the cover
and the bottom are designed as identical parts.
12. The heat transfer unit according to claim 1, wherein the first
flow channels run parallel to one another.
13. The heat transfer unit according to claim 2, wherein the cover
and/or the bottom has/have at least one reinforcing element.
14. The heat transfer unit according to claim 2, wherein the cover
is connected to the bottom by at least one web.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from German Patent
Application No. DE 10 2006 040 851.9, filed Aug. 31, 2006, which is
hereby incorporated by reference in its entirety.
BACKGROUND
[0002] The invention relates to a heat exchanger unit, in
particular a charge air cooler with a housing in which first there
are flow channels for a gas to be cooled and separately therefrom
there are second flow channels for a cooling medium according to
the preamble of Claim 1.
[0003] Charge air coolers are used in supercharged internal
combustion engines, in particular in commercial vehicles, to
increase engine performance. Such a charge air cooler is arranged
in the intake tract of the gasoline engine downstream from a
charging device, e.g., a turbocharger.
[0004] DE 103 02 948 A1, for example, discloses a heat exchanger,
in particular an exhaust gas cooler for motor vehicles equipped
with flow channels arranged in a housing for a gas to be cooled and
for a coolant. The flow channels for the gas pass through pipe
plates into an intake and exhaust diffuser, while the coolant is
carried through the housing via coolant connections. The flow
channels for the gas and the coolant are formed by a shaped metal
strip around the housing, in particular in a meandering pattern and
joined together by bonding. The individual parts of the heat
exchanger are made of metal and soldered together.
[0005] Additional heat exchanger units are known from DE 103 02 708
A1, DE 103 52 187 A1, DE 100 57 190 A1 and DE 101 46 258 A1, for
example.
SUMMARY OF THE INVENTION
[0006] The present invention relates to the problem of providing an
improved embodiment or at least a different embodiment for a heat
transfer unit of the type defined above, so that it has a simple
design and can therefore be manufactured inexpensively.
[0007] This problem is solved by a heat exchanger unit having all
the features of Patent Claim 1. Advantageous and expedient
embodiments of the invention are the subject of the dependent
subclaims.
[0008] The invention is based on the general idea of designing a
heat exchanger unit that has previously been made completely of
metal and soldered together in its manufacture, so it is now made
of at least two different materials, namely a metal and a plastic,
wherein the metallic material is used for the first flow channels,
which are sheathed plastic on their longitudinal ends to form a
shared tube plate. This allows a great simplification in
manufacturing the inventive heat exchanger unit, wherein only the
hollow metallic bodies forming the first flow channels need be
inserted into a corresponding injection mold, wherein the
longitudinal ends of the metal hollow bodies are sheathed in a
molded tube place encompassing all the hollow bodies. In particular
this allows savings in terms of adjustment, clamping and soldering
of the individual parts, which would usually be necessary with heat
exchanger units made of metallic components, thus allowing the
manufacturing process to be made more efficient and less expensive.
In principle, the first flow channels are designed for conveyance
of gas to be cooled, in particular charging air or exhaust gas,
whereas second flow channels that are spatially separate are
provided for transporting a cooling medium. The second flow
channels are bordered by outsides of the hollow metallic bodies of
the first flow channels, the two tube plates designed on the
longitudinal ends of the first flow channels and by the inside of
the housing made of plastic. Making the inventive heat exchanger of
two different materials not only simplifies the manufacturing
process of the heat exchanger unit but also permits virtually any
type of shaping, in particular the second flow channels which are
made mainly of plastic and/or the housing which is made of plastic,
thus resulting in a great deal of structural freedom.
[0009] Two side walls of the housing are expediently integrally
molded onto the two tube plates, e.g., two side walls are
integrally molded together with the tube plates onto the first flow
channels. Integral molding and/or simultaneous production of the
side walls and the tube plates eliminates the need for assembling
these individual parts subsequently, thus making it possible to
improve production efficiency.
[0010] In an advantageous embodiment of the inventive approach, at
least a part of the housing is a component of an intake system of
an internal combustion engine. To further reduce the multitude of
parts, the goal is to design one of the tube plates, a side wall or
a cover and/or a bottom of the inventive heat transfer device, for
example, as a connecting part to the intake system of the internal
combustion engine. In this way, an especially compact design can be
achieved while at the same time allowing a lighter weight, which is
a great advantage, especially in view of the ever smaller amount of
space available in the engine compartment.
[0011] In another advantageous embodiment of the inventive
approach, the first flow channels are made of aluminum. This offers
the advantage that aluminum very rapidly forms an almost
impenetrable oxide layer in air, which makes the aluminum very
corrosion-resistant. Since the second material used, namely
plastic, does not undergo corrosion at all, a very
corrosion-resistant heat transfer unit can be created on the whole
by using aluminum as the lightweight metal. In addition, aluminum
has a very high thermal conductivity, which is especially desired
for the heat exchange in a heat transfer unit to be able to achieve
efficient cooling of the charge air, for example. Of course
aluminum alloys which improve the aforementioned properties and/or
additionally improve processability may also be used here.
[0012] Other important features and advantages of the invention are
derived from the subclaims, the drawings and the respective
description of figures on the basis of the drawings.
[0013] It is self-evident that the features mentioned above and
those yet to be explained below may be used not only in the
particular combination given but also in other combinations or
alone without going beyond the scope of the present invention.
[0014] Preferred exemplary embodiments of the invention are
depicted in the drawings and explained in greater detail in the
following description, where the same reference numerals are used
to refer to the same or similar or functionally identical
components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The drawings show schematically,
[0016] FIG. 1 a partially cutaway view of an inventive heat
transfer device,
[0017] FIG. 2 a detailed view of the sectional area of the heat
transfer device according to FIG. 1,
[0018] FIG. 3 a view of a possible embodiment of the first metallic
flow channels,
[0019] FIG. 4 a diagram like that in FIG. 3, but with tube plates
plus side walls integrally molded onto the first flow channels at
the ends.
DESCRIPTION
[0020] According to FIG. 1, an inventive heat transfer unit 1 has a
housing wall 2 in which are arranged first flow channels 3 for the
gas to be cooled, in particular charge air or exhaust gas, and
separately therefrom, second flow channels 4 for a cooling medium
(see also FIG. 2). In the present case, the heat transfer unit 1 is
designed as a charge air cooler as an example. Such a charge air
cooler is usually provided for increasing the performance of a
combustion engine and, by cooling the intake air after it is
compressed by a charging device and/or a compressor, the quantity
of air entering the cylinder with the intake is such that more fuel
can be burned per working cycle at a given fuel/air ratio.
[0021] According to this invention, the first flow channels 3
consist of hollow metallic bodies which are sheathed in plastic on
their longitudinal end sides 5, 5' to form a shared tube plate 6,
6'. The second flow channels 4 are bordered by the outsides of the
hollow metallic bodies, the two tube plates 6, 6' and an inside of
the housing 2, which is otherwise made of plastic.
[0022] In contrast with traditional heat transfer devices, the heat
transfer unit 1 according to this invention is made of at least two
different materials, namely metal and plastic, so that the
manufacturing and/or finishing process of the inventive heat
transfer unit 1 is greatly simplified and is therefore less
expensive. In particular, this eliminates any complicated
adjustment, fixation and then soldering of the individual parts of
the heat transfer unit. It is also conceivable here that in
sheathing the longitudinal ends 5, 5' of the first flow channels 3,
not only the tube plates 6, 6' but at the same time also two side
walls 7, 7' joining the two tube plates 6, 6' are manufactured
together in one operation with the injection of the two tube plates
6, 6'. For finishing housing 2, which in addition to the two tube
plates 6, 6' and the two side walls 7, 7' also comprises a cover 8
and a bottom 9, thus only the cover 8 and the bottom 9 are each to
be joined to the tube plates 6, 6' and/or to the side walls 7, 7'.
Such a connection may be established, for example, by gluing or by
means of a friction weld that is resistant to both coolants and
temperatures.
[0023] As shown in FIG. 1, both the cover 8 and the bottom 9 each
have a cooling medium connection 10, 10' by means of which the heat
transfer unit 1 can be connected to a coolant circuit. Such a
cooling medium connection 10, 10' may be designed, for example, in
the manner of a traditional male or female connection or the like.
To be able to reduce the multitude of parts in addition to
simplifying the manufacturing process of the inventive heat
transfer unit 1, the cover 8 and the bottom 9 are preferably
designed as identical parts and therefore mav be used both as the
bottom 9 and as the cover 8.
[0024] The heat transfer unit 1 is under the pressure of the
cooling medium flowing in the heat transfer unit 1 during
operation, so reinforcing elements 11, e.g., flanging, may be
provided on the cover 8 and/or on the bottom 9. As an alternative
or in addition, it is also conceivable for the cover 8 to be
connected to the bottom 9 by at least one web (not shown) capable
of withstanding tensile stress. Such a web as well as at least one
reinforcing element 11, as mentioned above, limit deformation of
the cover 8 and/or the bottom 9, which is induced under some
circumstances by the coolant pressure in the interior of the heat
transfer unit 1. Such reinforcing elements 11 may of course also be
arranged on the side walls 7, 7' and may therefore limit
deformation thereof.
[0025] A sealing element 13 which additionally supports a seal
between the first flow channels 3 and the second flow channels 4 is
provided at the longitudinal end of the first flow channels 3. Such
a sealing element 13 may be made of a TPE plastic (thermoplastic
elastomer or thermal polyethylene), for example. On the other hand,
the housing 2, in particular the tube plates 6, 6' and the side
walls 7, 7' are made of a polyamide, i.e., nylon. The TPE plastic
is necessary for the sealing element 13 to achieve a tight seal
between the surface of the first flow channels 3, i.e., between the
surface of the hollow bodies and the integrally molded tube plates
6, 6' because the polyamide cannot be attached directly to metal.
From a manufacturing standpoint, the sealing element 13 can be
produced either before or after integral molding of the tube plates
6, 6' onto the longitudinal ends 5, 5' of the first flow channels
3.
[0026] As shown in FIG. 3, the first flow channels 3 run parallel
to one another and have a rectangular cross section that is rounded
in the corner areas. All the first flow channels 3 shown here have
the same cross section and the same length, so it is conceivable
that a hollow body designed as bar stock could be cut to the proper
length to produce the first flow channels 3 and the individual
pieces later arranged parallel to one another, e.g., by means of a
comb-like adjusting device.
[0027] FIG. 4 shows the hollow bodies arranged parallel to one
another, whereby their longitudinal ends 5, 5' are already sheathed
in plastic to form a shared tube plate 6, 6'. As mentioned above,
the side walls 7, 7' are preferably manufactured in the same step
of the operation in which the integral molding and/or sheathing of
the longitudinal ends 5, 5' of the first channels 3 to the tube
plate 6, 6' takes place.
[0028] To be able to further reduce the multitude of parts, it is
also conceivable for at least a portion of the housing 2 to be a
part of an intake system (not shown) of an internal combustion
engine, whereby in particular the cover 8, the bottom 9 or one of
the tube plates 6, 6' may be part of the intake system at the same
time. Such an embodiment ensures an especially compact design of
the inventive heat transfer device 1 and, as mentioned above,
reduces the multitude of parts and thereby also lowers costs.
[0029] To be able to additionally increase the heat transfer
between the gas that is to be cooled and the cooling medium, the
hollow bodies, i.e., the first flow channels 3 are preferably made
of aluminum which is characterized by a high thermal conductivity
on the one hand and also by a high corrosion resistance on the
other hand. In addition, aluminum is very lightweight, which has a
positive effect on the energy balance of the motor vehicle. In
addition to the use of a suitable material, i.e., in particular a
material with a high thermal conductivity, additional heat transfer
elements 12 may also be arranged inside the first flow channels 3,
these heat transfer elements being inserted, for example, into the
first flow channels 3 after sheathing of the longitudinal ends 5,
5' of the first flow channels 3 with the tube plates 6, 6' and then
connected thereto in a thermally conducting manner. Heat conducting
films, in particular running in a meandering pattern between two
side walls of the first flow channels 3, may be considered here as
the heat transfer elements 12.
* * * * *