U.S. patent application number 10/561847 was filed with the patent office on 2006-12-14 for module for cooling the charge air and recirculated exhaust gases from the internal combustion engine of a motor vehicle.
Invention is credited to Matthieu Chantreau, Carlos Martins, Michel Potier.
Application Number | 20060278377 10/561847 |
Document ID | / |
Family ID | 33518423 |
Filed Date | 2006-12-14 |
United States Patent
Application |
20060278377 |
Kind Code |
A1 |
Martins; Carlos ; et
al. |
December 14, 2006 |
Module for cooling the charge air and recirculated exhaust gases
from the internal combustion engine of a motor vehicle
Abstract
The cooling module consists of a charge air cooler and of a
recirculated exhaust gas cooler. The charge air cooler comprises a
heat exchange bundle (2), an inlet header box for the air that is
to be cooled and an outlet header box for the cooled air. The
recirculated exhaust gas cooler comprises a heat exchange bundle
(4) for cooling the recirculated exhaust gases, an inlet header box
for the recirculated exhaust gases and an outlet header box for
these gases. A wrapper consisting of two half-casings (7 and 8)
accommodates the exchange bundles (2 and 4). The charge air cooler
heat exchange bundle (2) and the recirculated exhaust gas cooler
heat exchange bundle (4) are assembled in a single brazing
operation. They are also assembled with one another during this
same brazing operation, possibly at the same time as the two
half-casings (7 and 8).
Inventors: |
Martins; Carlos; (Le
Chesnay, FR) ; Chantreau; Matthieu; (Saulx Marchais,
FR) ; Potier; Michel; (Rambouillet, FR) |
Correspondence
Address: |
Berenato White & Stavish
Suite 240
6550 Rock Spring Drive
Bethesda
MD
20817
US
|
Family ID: |
33518423 |
Appl. No.: |
10/561847 |
Filed: |
June 24, 2004 |
PCT Filed: |
June 24, 2004 |
PCT NO: |
PCT/FR04/01595 |
371 Date: |
August 9, 2006 |
Current U.S.
Class: |
165/140 |
Current CPC
Class: |
F02M 26/10 20160201;
F02M 26/17 20160201; F02M 26/11 20160201; F28F 2275/04 20130101;
F28D 9/0056 20130101; F02M 26/30 20160201; F28D 2021/0082 20130101;
F02B 29/0493 20130101; F02B 29/0418 20130101; F02M 31/20 20130101;
F02B 29/0412 20130101; F02B 29/0475 20130101; Y02T 10/12 20130101;
F28D 9/0043 20130101; F28D 7/0083 20130101; F02B 29/0462 20130101;
F28D 21/0003 20130101; F28F 9/001 20130101; F02M 26/32 20160201;
F28F 2250/102 20130101; F28D 7/0075 20130101; F28F 21/067
20130101 |
Class at
Publication: |
165/140 |
International
Class: |
F28D 1/03 20060101
F28D001/03 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 25, 2003 |
FR |
03/07674 |
Nov 28, 2003 |
FR |
03/14044 |
Claims
1. A cooling module consisting of a charge air cooler and a
recirculated exhaust gas cooler, the charge air cooler comprising a
heat exchange bundle (2) for cooling the charge air and the
recirculated exhaust gas cooler comprising a heat exchange bundle
(4) for cooling the recirculated exhaust gases, characterized in
that the charge air cooler heat exchange bundle (2) and the
recirculated exhaust gas cooler heat exchange bundle (4) are
assembled in a single brazing operation and in that they are also
assembled with one another during this same brazing operation.
2. The cooling module as claimed in claim 1, further comprising a
wrapper (6) housing the charge air cooler and recirculated exhaust
gas cooler bundles (2, 4), said wrapper (6) being assembled with
these bundles during the single brazing operation during which
these bundles are assembled with one another.
3. The cooling module as claimed in claim 2, characterized in that
the charge air cooler further comprises an inlet header box (30)
for the air that is to be cooled immediately adjacent to an inlet
end of the charge air cooler heat exchange bundle (2) and an outlet
header box (32) for the cooled air immediately adjacent to an
outlet end of the charge air cooler heat exchange bundle (2), and
in that the wrapper (6) comprises a first and a second peripheral
rim which protrude on each side of the charge air cooler bundle
(2), the charge air cooler inlet header box being assembled with
one of these rims, the charge air cooler outlet header box (32)
being assembled with the other of these peripheral rims.
4. The cooling module as claimed in claim 3, characterized in that
the dimensions of the wrapper (6) are chosen such that they delimit
a first and a second empty space (88, 90), one at an inlet end and
one at an outlet end of the charge air cooler heat exchange bundle
(2), the first and second empty spaces respectively constituting an
inlet header box and an outlet header box for the charge air.
5. The cooling module as claimed in claim 2 4, characterized in
that the wrapper (6) comprises two half-casings (7, 8).
6. The cooling module as claimed in claim 5, characterized in that
the two half-casings (7, 8) are able to slide one with respect to
the other in order to accommodate variations in height of at least
one of the heat exchange bundles (2, 4).
7. The cooling module as claimed in claim 5, characterized in that
each of the two half-casings (7, 8) has a U-shaped cross section
comprising an end wall (10) and two lateral edges (12) situated one
on each side of the end wall (10), the lateral edges (12) of one of
the half-casings sliding with respect to the lateral edges of the
other half-casing.
8. The cooling module as claimed in claim 5, characterized in that
each of the two half-casings (7, 8) has the shape of a container
comprising a peripheral rim, the peripheral rim of one half-casing
being able to fit into the peripheral rim of the other half-casing
and to slide with respect to the latter.
9. The cooling module as claimed in claim 2, characterized in that
the wrapper (6) comprises a pressed housing (14) which accommodates
the recirculated exhaust gas cooler bundle (4).
10. The cooling module as claimed in claim 2, characterized in that
the wrapper (6) comprises a separate recirculated exhaust gas
cooler casing (73), this separate casing (73) being brazed in a
single operation to one of the two half-casings (7, 8) during the
single brazing operation during which the bundles (2, 4) are
assembled with one another.
11. The cooling module as claimed in claim 9, characterized in that
the recirculated exhaust gas cooler comprises an inlet header box
(16) for the recirculated exhaust gases immediately adjacent to an
inlet end of the recirculated exhaust gas cooler heat exchange
bundle (4) and an outlet header box (18) for the recirculated
exhaust gases immediately adjacent to an outlet end of the
recirculated exhaust gas cooler heat exchange bundle (4), the
housing (14) or the separate casing (76) for the recirculated
exhaust gas cooler bundle (4) delimiting a first and a second empty
space (16, 18), one at an inlet end and one at an outlet end of the
recirculated exhaust gas cooler heat exchange bundle, the first and
second empty spaces respectively constituting the inlet header box
(16) and the outlet header box (18) for the recirculated exhaust
gases.
12. The cooling module as claimed in claim 5, characterized in that
at least one of the two half-casings comprises an end wall which is
taller so as to make it easier to install the recirculated exhaust
gas cooler.
13. The cooling module as claimed in claim 5, characterized in that
it comprises a passage (18, 72, 79) for the recirculated exhaust
gases which opens directly into the outlet header box (32) of the
charge air cooler, the cross section of this passage being equal to
or greater than the cross section of the recirculated exhaust gas
cooler bundle (4).
14. The cooling module as claimed in claim 1 in which the charge
air cooler heat exchange bundle (2) and the recirculated exhaust
gas cooler heat exchange bundle (4) are made of aluminum and/or
aluminum alloy.
15. The cooling module as claimed in claim 14 in which the wrapper
(6) is also made of at least one of aluminum and aluminum
alloy.
16. The cooling module as claimed in claim 15 in which the header
boxes (16, 18, 30, 32) of said coolers are also made of at least
one of aluminum and aluminum alloy.
Description
[0001] The invention relates to internal combustion engine motor
vehicles.
[0002] It relates more particularly to a cooling module consisting
of a charge air cooler and of a recirculated exhaust gas cooler,
the charge air cooler comprising a heat exchange bundle for cooling
the charge air, an inlet header box for the air that is to be
cooled immediately adjacent to an inlet end of the charge air
cooler heat exchange bundle and an outlet header box for the cooled
air immediately adjacent to an outlet end of the charge air cooler
heat exchange bundle, the recirculated exhaust gas cooler
comprising a heat exchange bundle for cooling the recirculated
exhaust gases, an inlet header box for the recirculated exhaust
gases which is immediately adjacent to an inlet end of the
recirculated exhaust gas cooler heat exchange bundle and an outlet
header box for the recirculated exhaust gases immediately adjacent
to an outlet end of the recirculated exhaust gas cooler heat
exchange bundle, a wrapper housing the charge air cooler heat
exchange bundle and the recirculated exhaust gas cooler heat
exchange bundle.
[0003] In order to increase the specific power of motor vehicle
combustion engines, it is known practise for them to be supplied
with charge air that has been compressed using a compressor driven
by the exhaust gases. However, this compression has the effect of
raising the charge air to a high temperature. For this reason, the
charge air has to be cooled before it is introduced into the
combustion chambers of the engine. This cooling is performed in the
conventional way in an air cooler known as a charge air cooler or
intercooler.
[0004] Furthermore, in order to meet increasingly tight pollution
standards, it is known practise for some of the exhaust gases to be
recirculated and mixed with the fresh inlet gases in order to lower
the combustion temperature in the engine. However, these
recirculated exhaust gases are at a high temperature which may be
as high as about 500.degree. C., which means that they too have to
be cooled. Conventionally, this cooling is done by passing them
through a recirculated exhaust gas cooler.
[0005] In order to reduce the space occupied by these two coolers
it is common practise for them to be housed in a single unit (DE 19
853 455). That document describes a module consisting of a charge
air cooler housed in a unit and of a recirculated exhaust gas
cooler mounted on the charge air cooler. The main feature of this
module is that there is a funnel-shaped device positioned at the
interface between the charge air and recirculated gas outlets. The
recirculated exhaust gas outlet is downstream of the charge air
outlet.
[0006] However, assembly of a cooling module of this type is done
using conventional mechanical means such as screws or bolts. It
therefore entails a significant number of operations which take
time and increase the cost of manufacture of the module.
[0007] Furthermore, in order to meet increasingly tight pollution
standards, a need to have more precise control over the temperature
of the mixture of inlet air and recirculated gases admitted to the
engine is now felt.
[0008] The invention is aimed specifically at a cooling module that
meets these objectives. The first of these objectives is achieved
through the fact that the charge air cooler heat exchange bundle
and the recirculated exhaust gas cooler heat exchange bundle are
assembled in a single brazing operation and in that they are also
assembled with one another during this same brazing operation.
[0009] All or some of the components of the module, especially the
bundles of each of the coolers, can thus be made of a single
material, for example aluminum and/or an aluminum alloy.
[0010] Advantageously, the wrapper housing the heat exchange
bundles of the charge air cooler and of the recirculated exhaust
gas cooler is assembled with these bundles during the single
brazing operation during which these bundles are assembled with one
another. In particular, the wrapper is made of the same single
material, for example aluminum and/or an aluminum alloy, as the
cooler bundles.
[0011] By virtue of this feature, assembling the cooling module can
be done in a single operation and without the need to resort to
mechanical means of assembly such as screws or bolts. It is
therefore quicker to manufacture and its cost price is lower.
[0012] According to a first embodiment, the wrapper comprises a
first and a second peripheral rim which protrude on each side of
the charge air cooler bundle, the charge air cooler inlet header
box being assembled with one of these peripheral rims, the charge
air cooler outlet header box being assembled with the other of
these peripheral rims.
[0013] In this embodiment, the inlet and outlet header boxes of the
charge air cooler are attached after the brazing operation has been
performed. They can therefore be produced by molding in a different
material, for example in plastic.
[0014] According to another embodiment, the dimensions of the
wrapper are chosen such that they delimit a first and a second
empty space, one at the inlet end and one at the outlet end of the
charge air cooler heat exchange bundle, the first and second empty
spaces respectively constituting an inlet header box and an outlet
header box for the charge air.
[0015] In this embodiment, the cooling module is entirely assembled
in a single operation, including the inlet and outlet header boxes
delimited by the wrapper itself. The module is then produced in a
single material, for example an aluminum alloy.
[0016] In an advantageous embodiment, the wrapper comprises two
half-casings. These two half-casings may be able to slide one with
respect to the other in order to accommodate variations in height
of at least one of the heat exchange bundles.
[0017] When the inlet and outlet header boxes of the charge air
cooler are added on, each of the two half-casings advantageously
has a U-shaped cross section comprising an end wall and two lateral
edges situated one on each side of the end wall, the lateral edges
of one of the half-casings sliding with respect to the lateral
edges of the other half-casing.
[0018] When the cooling module is made entirely in aluminum, each
of the two half-casings advantageously has the shape of a container
comprising a peripheral rim, the peripheral rim of one half-casing
being able to fit into the peripheral rim of the other half-casing
and to slide with respect to the latter.
[0019] Whatever the embodiment, the wrapper may, in one particular
embodiment, comprise a pressed housing which accommodates the
recirculated exhaust gas cooler bundle.
[0020] In another embodiment, the wrapper comprises a separate
charge air cooler casing, this separate casing being brazed in a
single operation to one of the two half-casings during the single
brazing operation during which the bundles are assembled with one
another.
[0021] One of the half-casings may advantageously comprise an end
wall that is taller to make it easier to install the recirculated
exhaust gas cooler.
[0022] Finally, according to another advantageous feature of the
invention, the cooling module comprises a passage for the
recirculated exhaust gases which opens directly into the outlet
header box of the charge air cooler, the cross section of this
passage being equal to or greater than the cross section of the
recirculated exhaust gas cooler bundle.
[0023] By virtue of this feature, the inlet air and the
recirculated gases are indeed mixed upstream of the inlet ducts.
The gases can mix and their temperature can therefore even out, so
that the temperature of the mixture is lowered.
[0024] Furthermore, the fact that the passage cross section for the
recirculated exhaust gases can be at least equal to the cross
section of the recirculated exhaust gas cooler bundle allows these
gases not to experience any pressure drop and improves the
uniformity of the mixing.
[0025] Other features and advantages of the invention will become
further apparent from reading the description which follows of some
exemplary embodiments which are given by way of illustration with
reference to the attached figures. In these figures:
[0026] FIG. 1 is an external perspective view of a first embodiment
of a cooling module according to the invention;
[0027] FIG. 2 is an exploded view, minus the header boxes, of the
module depicted in FIG. 1;
[0028] FIG. 3 is a view of the module of FIGS. 1 and 2 in cross
section on a plane passing through the center of the exhaust gas
inlet flange;
[0029] FIG. 4 is a view of the cooling module in longitudinal
section on a plane passing through the axis of one of the cooling
water ducts;
[0030] FIG. 5 is a detailed view in section illustrating the
structure of the charge air cooler heat exchange bundle;
[0031] FIG. 6 is a perspective exterior view of a variant
embodiment of the module of FIG. 1;
[0032] FIG. 7 is a perspective view, minus header box, of the
module of FIG. 6;
[0033] FIG. 8 is an exploded perspective view of the module of
FIGS. 6 and 7;
[0034] FIG. 9 is an exterior view in perspective of a second
embodiment of a cooling module according to the invention
comprising added-on header boxes;
[0035] FIG. 10 is a perspective view from beneath of the module of
FIG. 9;
[0036] FIG. 11 is a perspective view, minus header box, of the
module of FIGS. 9 and 10;
[0037] FIG. 12 is a view of the module of FIG. 9 in longitudinal
section on a plane passing through the axis of one of the cooling
water ducts;
[0038] FIG. 13 is a view in cross section on a plane passing
through the axis of the recirculated exhaust gas inlet flange;
[0039] FIG. 14 is an exterior perspective view of a cooling module
according to the invention, made entirely in aluminum;
[0040] FIG. 15 is a view from above of the cooling module of FIG.
14;
[0041] FIG. 16 is a view in section on XVI-XVI of FIG. 15;
[0042] FIG. 17 is a view in section on XVII-XVII of FIG. 15;
and
[0043] FIG. 18 is a view in section on XVIII-XVIII of FIG. 15.
[0044] The cooling module of the invention is intended to equip a
motor vehicle having an internal combustion engine comprising two
cooling circuits: a high-temperature first circuit for cooling the
combustion engine and a low-temperature second circuit for cooling
certain vehicle equipment items. This module consists of a charge
air cooler and of a recirculated exhaust gas cooler. Each of these
coolers itself consists of a heat exchange bundle, of an inlet
header box immediately adjacent to an inlet end of the heat
exchange bundle and an outlet header box immediately adjacent to an
outlet end of the heat exchange bundle. The gas to be cooled,
namely the charge air or the recirculated exhaust gases, is
introduced into the inlet header box of the cooler. It passes
through the heat exchange bundle giving up heat to a cooling fluid,
generally the water of the low-temperature circuit, then opens into
the outlet header box.
[0045] In the example depicted in FIGS. 1 to 5, the charge air
cooler bundle is denoted by the general reference 2 and the
recirculated exhaust gas cooler bundle is denoted by the general
reference 4. The bundles 2 and 4 are separated from one another by
an interface plate 5 (FIG. 2).
[0046] In order to reduce the space required by the module, as
previously explained, the bundles 2 and 4 are housed inside a
common wrapper 6. In the embodiment of FIGS. 1 to 5, the wrapper 6
consists of two half-casings, namely a first half-casing 7 and a
second half-casing 8. Each half-casing 7, 8 has a very elongate
U-shaped cross section comprising an end wall 10 and two lateral
edges 12 situated one on each side of the end wall 10. The lateral
edges 10 of the half-casings 7 and 8 are able to slide one with the
other in such a way as to adjust the height of the wrapper 6 to
accommodate dimensional variations in the heat exchange bundles 2
and 4. This is because, as a result of manufacturing tolerances,
the height of these bundles may vary slightly.
[0047] One of the two half-casings, in this instance the
half-casing 8, has a housing 14, made for example by pressing and
intended to accommodate the recirculated exhaust gas cooler bundle
4. As can be seen more specifically in FIG. 4, in one of its
dimensions, directed along the longest dimension of the heat
exchange bundle 4, the housing 14 is dimensioned in such a way as
to fit the length of the bundle 4. By contrast, as can be seen more
particularly in FIG. 3, in its other dimension, directed along the
width of the heat exchange bundle 4, the housing 14 is dimensioned
in such a way as to form an empty space 16 at the inlet end 17 of
the bundle 4 and an empty space 18 at the outlet end 19 of this
same bundle. The empty spaces 16 and 18 thus respectively
constitute an inlet header box 16 and an outlet header box 18 for
the recirculated exhaust gas cooler.
[0048] An inlet flange 20 is connected to an inlet duct 22 which
opens into the inlet header box 16 (FIG. 3). The flange 20 is for
the connection of an inlet pipe (not depicted) carrying the exhaust
gases that are to be cooled. An inlet duct 24 and an outlet duct 26
are also provided on the housing 14 of the half-casing 8. The ducts
24 and 26 respectively let a cooling fluid, generally the water of
the low-temperature circuit, in to an out of the recirculated
exhaust gas cooler bundle 4 and the charge air cooler bundle 2. In
the module depicted, the channels along which the cooling fluid
circulates through the bundles 2 and 4 are connected in parallel.
In other words, the ducts 24 and 26 are common to the two bundles,
thus reducing the number of external connections to be made.
[0049] The cooling module depicted in FIGS. 1 to 5 further
comprises an inlet header box 30 and an outlet header box 32 for
the charge air. Unlike the header boxes 16 and 18 of the
recirculated exhaust gas cooler, the inlet 30 and outlet 32 header
boxes of the charge air cooler are not directly delimited by the
wrapper 6 but are added on. That allows them to be made of a
material that differs from that of the wrapper 6 and of the heat
exchange bundles 2 and 4, for example of plastic. The inlet header
box comprises an inlet duct 34 and the outlet header box an outlet
duct 36. The charge air enters the inlet header box via the duct 34
as depicted schematically by the arrow 38, passes through the heat
exchange bundle 2, then opens into the outlet header box 32 before
leaving the heat exchange module in the outlet duct 36 as depicted
diagrammatically by the arrow 40.
[0050] To allow the inlet and outlet header boxes of the charge air
cooler to be fixed to the wrapper 6, each of the two half-casings 7
and 8 has a first and a second peripheral rim which protrude on
each side of the charge air cooler bundle 4. Advantageously,
grooves (not depicted) are formed in the feet of the header boxes
30 and 32. These grooves fit onto the peripheral rims of the
half-casings 7 and 8. The header boxes may be fixed to the wrapper
by any appropriate means, for example adhesive bonding.
[0051] As can be seen more particularly in FIG. 5 which depicts a
detailed view in section of the charge air cooler heat exchange
bundle 2, each of the heat exchange bundles 2 and 4 consists of a
stack of plates 42 between which there are corrugated inserts 44
constituting heat-exchange surfaces which improve the exchange of
heat between the charge air that is to be cooled and the plates.
Each plate is of roughly rectangular shape having two short sides
and two long sides. Each plate comprises an end wall 46 bounded by
a peripheral rim 48. Ribs 50 may be provided in the end wall 46 of
each of the plates to delimit circulation passages for the cooling
fluid (FIG. 2).
[0052] The end wall 46 and the peripheral rim 48 determine a
shallow dish. The plates are grouped together in pairs assembled by
their peripheral rim 48. Thus, the dish of the top plate and the
dish of the bottom plate belonging to the same pair of plates
combine to form a channel 52 through which the cooling fluid can
circulate. Furthermore, two bosses 54 are formed along a short side
of each of the plates. The bosses of a pair of plates press against
the bosses of the adjacent plate pairs. This then produces an inlet
manifold and an outlet manifold for the cooling fluid. The cooling
fluid enters the bundle as depicted diagrammatically by the arrow
56 then flows through the circulation channels 52 as depicted
diagrammatically by the arrows 58. The fluid leaves the heat
exchange bundle 2 in the opposite direction.
[0053] The bosses 54 of two pairs of plates also between them
determine circulation channels 60 for the charge air of the charge
air cooler and for the exhaust gases of the exhaust gas cooler.
Turbulence generators 44 are positioned in the circulation passages
60.
[0054] As regards the recirculated exhaust gas cooler bundle 4 more
particularly, each circulation channel for the exhaust gases that
are to be cooled may advantageously lie between two channels for
the circulation of the cooling liquid. By virtue of this feature,
the wall of the pressed housing 14 and the interface plate 5 are
not in direct contact with the gases that are to be cooled, the
temperature of which may be very high (500.degree. C.). On the
contrary, these walls are cooled by the circulation of the cooling
liquid. Their temperature is thus considerably lowered by
comparison with the wall temperature of a conventional recirculated
exhaust gas cooler. It may for example be of the order of
200.degree. C. These walls can therefore be made in a material with
less resistance to temperature, such as aluminum. This advantage is
considerable because aluminum is easier to work and less expensive
than stainless steel.
[0055] As can be seen more specifically in FIG. 3, the empty space
18 formed in the housing 14, which constitutes the outlet header
box for the recirculated exhaust gas cooler is in direct
communication with the interior space 70 of the outlet header box
32 of the charge air cooler. In consequence, the cross section of
the passage offered to the cooled recirculated exhaust gases is the
cross section of the outlet header box 18. This cross section is
equal to the cross section of the exhaust gas cooler bundle 4.
These exhaust gases can therefore arrive in the charge air cooler
outlet header box 32 without their flow being retarded. In
particular, they do not have to negotiate any passage of narrowed
cross section which would incur a pressure drop.
[0056] FIGS. 6 to 8 depict a variant embodiment of the cooling
module of FIGS. 1 to 5. The overall construction of the cooler of
FIGS. 6 to 8 is identical to that of the first embodiment. In
consequence, the same elements have been denoted by the same
reference numerals. The difference lies in the fact that the
pressed housing 14 in the half-casing 8, instead of having a width
equal to the longest dimension of the plates of the heat exchange
bundle 4 of the recirculated exhaust gas radiator, has a part 72 of
enlarged cross section. In the example, the enlarged section 72
extends over the entire length of the cooling module. In other
words, its length is equal to the length of the plates of the
charge air cooler heat exchange bundle 2, this length also
corresponding to the length of the outlet header box 32 of this
cooler.
[0057] As a result, in this embodiment, the passage cross section
offered to the recirculated exhaust gases once they have passed
through the cooler bundle 4 is not equal to but greater than the
cross section of the heat exchange bundle 4. This feature allows
for better mixing of the recirculated exhaust gases with the fresh
gases from the outlet header box 32. What happens is that as soon
as they leave the heat exchange bundle 4, the recirculated exhaust
gases can spread over the entire length of the cooling module. As a
result, they mix with all of the charge air rather than
preferentially with the charge air lying on the same side as the
exhaust gas cooler.
[0058] FIGS. 9 to 13 depict a third variant embodiment of the
cooling module of the invention. In these figures, the same
elements bear the same reference numerals as in the preceding
figures. The module of FIGS. 9 to 13 differs through the presence
of a separate casing for the recirculated exhaust gas cooler bundle
4. Whereas, in the previous two embodiments, the bundle 4 of the
exhaust gas cooler was housed in a housing 14 pressed directly in
the half-casing 8, in this embodiment, the bundle 4 is housed in a
casing 76 designed as a separate part and added on to the
half-casing 8. The casing 76 can be fixed to the half-casing 8 by
any means within the competence of the person skilled in the art.
However, the casing 76 is preferably assembled by brazing in a
single operation. In other words, the single brazing operation
during which the bundles 2 and 4 of the coolers are assembled and
during which these bundles are assembled with one another and with
the wrapper 6 (consisting of the two half-casings 7 and 8 in the
examples) is put to use for assembling the separate casing 76 with
the half-casing 8. Thus, the presence of this additional part does
not entail any additional operation for assembling the cooling
module, except that of positioning the casing 76 on the half-casing
8. The inlet duct 24 and the outlet duct 26 for the cooling fluid
are provided on the separate casing, as is the recirculated exhaust
gas inlet duct 78.
[0059] The added-on casing 76 may be made of the same material as
the wrapper 6 or of a different material. However, if the casing 76
is to be assembled by brazing in a single operation, it is
preferable for the materials to be the same.
[0060] Just as for the pressed housing 14, the separate casing 76
has a long dimension (its length) which corresponds to the length
of the plates of the exhaust gas cooler heat exchange bundle 4. By
contrast, its short dimension (its width) is greater than the short
dimension of the plates of the bundle 4 so as to delimit an empty
space 16 at an inlet end of the bundle 4 and an empty space 18 at
an outlet end of this same bundle. The empty spaces 16 and 18, as
before, respectively constitute an inlet header box and an outlet
header box for the recirculated exhaust gases. An interface plate 5
separates the charge air cooler bundle 2 from the exhaust gas
cooler bundle 4. The interface plate closes off the inlet and
outlet header boxes 16 and 18. One or more perforations 79, forming
communication passages, are formed in the interface plate 5 to
place the outlet header box 18 in communication with the internal
volume of the outlet header box 32 of the charge air cooler (see
FIG. 13).
[0061] The embodiment of FIGS. 9 to 13 also differs in that one of
the two half-casings, in this instance the half-casing 8, comprises
an end wall 10 the width of which exceeds that of the end wall of
the other half-casing, the half-casing 7 in this example. This
arrangement is advantageous because it offers even more space for
installing the recirculated exhaust gas cooler. In particular, when
the cooling module comprises an added-on separate casing 76, it is
necessary to provide, at the periphery of this casing, an empty
region so that the contacting surfaces of the casing 76 and of the
end wall 10 can be brazed. The fact of increasing the width of the
end wall also allows the inlet header boxes 16 and 18 to be more
generously sized.
[0062] It is pointed out that, in this embodiment, the passage 79
which places the outlet header box 18 of the exhaust gas cooler in
communication with the internal volume of the outlet box 32 of the
charge air radiator has a passage cross section roughly equal to
the cross section of the bundle 4. It goes without saying that,
according to a variant embodiment, this passage cross section could
be enlarged so that it extends over the entire length of the plates
of the charge air cooler bundle 2, as was described with reference
to FIGS. 6 to 8. To achieve that, all that would be required would
be a modification to the shape of the added-on casing 76, equipping
it with an extension 72 similar to the extension of the pressed
housing 14 of FIGS. 6 to 8.
[0063] FIGS. 14 to 18 depict a fourth variant embodiment of the
cooling module of the invention. This embodiment is characterized
in that it comprises no added-on inlet and outlet header boxes 30,
32 for the charge air cooler. What happens is that these header
boxes are formed directly by empty spaces positioned on each side
of the charge air radiator heat exchange bundle 2.
[0064] Each half-casing 7, 8 has an end wall 10 that is generally
flat and of square or rectangular shape, and four lateral walls 80
connected to the end wall 10 by a fillet and approximately
perpendicular to this wall. The lateral walls 80 of the two
half-casings fit together in such a way as to allow the two
half-casings to slide one relative to the other in order to
accommodate slight variations in height of the bundles 2 and 4. A
charge air inlet duct 82 is provided on the half-casing 7 and a
charge air outlet duct 84 is provided on the half-casing 8.
[0065] As can be seen in particular in FIG. 16, the charge air
enters the cooling module via the inlet duct 82 as depicted
schematically by the arrow 86. It reaches the inlet header box 88
then passes through the charge air cooler heat exchange bundle 2
exchanging heat with the cooling water. Having passed through the
bundle 2, the cooled charge air reaches the outlet header box 90
then leaves the cooling module via the duct 84 as depicted
schematically by the arrow 92. The recirculated exhaust gases enter
the cooling module via the flange 20, as depicted schematically by
the arrow 94; they pass right through the heat exchange bundle 4
and emerge directly, as depicted schematically by the arrow 96,
into the outlet header box 90 of the charge air cooler.
[0066] Advantageously, the passage cross section placing the
exhaust gas cooler in communication with the header box 90 is equal
to or greater than the passage cross section of the bundle 4.
[0067] The inlet and outlet ducts 82 and 84 may be made of aluminum
and brazed to the half-casings 7 and 8 during the single operation
of brazing the cooling module. Alternatively, like the duct 82 in
the example, they may be made of some other material, for example
of plastic and mounted after the brazing operation. The embodiment
of FIGS. 14 to 18 can therefore be achieved in a single material,
for example aluminum, which allows it to be assembled entirely in a
single brazing operation without even having to add on the charge
air cooler inlet and outlet header boxes as had to be done in the
preceding examples.
[0068] One of the two half-casings, the half-casing 8 in the
example, comprises a pressed housing 14 intended to accommodate the
exhaust gas cooler heat exchange bundle 4. As already described
earlier, one of the dimensions of the pressed housing 14 matches
the length of the plates of the bundle 4, while the other dimension
is able to form, respectively at an inlet end and at an outlet end
of the bundle 4, inlet 16 and outlet 18 header boxes for the
recirculated exhaust gases. It goes without saying that, in an
embodiment variant, the pressed housing 14 could be replaced by an
added-on separate casing identical to the casing 76 described
previously.
* * * * *