TECHNICAL FIELD
[0001] The present invention relates to an EGR/cooling integrated module for an IC engine.
BACKGROUND ART
[0002] It is well known that NOx emissions can be reduced by exhaust gas recirculation (EGR),
i.e. by recirculating a portion of exhaust gases to engine intake.
[0003] An EGR system includes a number of components: an EGR cooler, i.e. a heat exchanger
adapted to cool the exhaust gases before re-introducing them into the engine intake,
a bypass valve associated to the EGR cooler and adapted to selectively route the EGR
gases through the EGR cooler or bypass the cooler depending on engine operating parameters,
and an EGR valve which controls the EGR flow rate.
[0004] In order to reduce the number of components that have to be individually assembled
onto the engine and the number of associated parts, such as connecting pipes, and
therefore the overall cost of the system, it is well known to group such components
into pre-assembled modules that can be mounted to the engine as a single unit.
[0005] The EGR cooler uses the engine coolant as the cooling fluid, therefore the module
must be connected to the engine cooling system; furthermore, the EGR and bypass valve
also require proper cooling because of the extremely high temperature of the exhaust
gases.
[0006] Because of this necessary interaction between the EGR and the cooling systems, and
the general goal to reduce manufacturing and assembly costs, it has been proposed
to include one or more components of the cooling circuit into the EGR module.
[0007] An example of these known multifunctional EGR/cooling integrated modules modules
is disclosed in
EP-A-1 793 115. This prior art module includes an EGR/cooling integrated module for an IC engine
including an interface member adapted to be mounted to the engine, and further including
an EGR valve, an EGR cooler and a bypass valve carried and interconnected by the interface
member, wherein
- the interface member includes a coolant inlet aperture and an EGR gas inlet aperture
adapted to be connected directly to corresponding ports of said engine upon assembling
said module to said engine,
- the interface member defines a housing of said EGR valve and a cooling circuit for
cooling said EGR valve,
- the EGR valve is housed in a cavity of said interface member, and includes a shutter
and a valve seat provided in said cavity,
- said cooling circuit includes a cooling cavity provided within said interface member
and communicating with the coolant inlet aperture said cooling cavity being adjacent
to said EGR valve,
- said bypass valve includes a bypass valve chamber said bypass valve chamber being
provided within said interface member , wherein the cooling cavity is adapted for
cooling the EGR valve chamber.
DISCLOSURE OF INVENTION
[0008] An object of the present invention is to provide an EGR/cooling module that is more
efficient and still more compact and less expensive to manufacture.
[0009] This object is achieved by an EGR/cooling integrated module as claimed in claim 1.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a better comprehension of the present invention, a preferred embodiment is described
hereafter, by way of a non-limiting example and with reference to the attached drawings,
in which:
Figure 1 is a front view of an EGR/cooling integrated module in accordance with the
present invention;
Figure 2 in a back view thereof;
Figure 3 is a perspective view of an interface member of the module;
Figure 4 is an axial cross section of an EGR valve of the module
Figure 5 and 6 are partial cross-sections of the module, showing a gas circuit in
two different operating configurations;
Figure 7 is a perspective view of an EGR cooler of the module which is part of the
integrated module of the invention;
Figure 8 is a perspective view of a thermostat/vacuum tank subassembly which is part
of the integrated module of the invention;
Figure 9 is a partial cross-section of the module showing a coolant circuit and the
connection between the interface member of Figure 3 and the subassembly of Figure
8;
Figure 10 is a cross section of a different embodiment of an EGR cooler; and
Figure 11 is a front view of a connecting flange of the EGR cooler of Figure 10.
BEST MODE FOR CARRYING OUT THE INVENTION
[0011] With reference to Figures 1 and 2, numeral 1 designates as a whole an EGR/cooling
integrated module in accordance with the present invention (hereinafter "module 1".
[0012] Module 1 includes an EGR valve 2, an EGR cooler 3 and a bypass valve 4 that are carried
and interconnected by a an interface member 5 (hereinafter "member 5") which is adapted
to be directly assembled onto a vehicle IC engine (not shown). Module 1 also includes
an electrically operated EGR valve actuator 6, a vacuum-operated bypass valve actuator
7, a vacuum tank 8 for actuator 7, and a coolant thermostat valve 9 (Figures 8, 9).
[0013] Member 5 (Figure 3) is conveniently an aluminium alloy die-casting and includes a
plurality of internal passages for EGR gases and coolant, as will be described below
in a more detailed manner.
[0014] Member 5 includes has a substantially flat base flange 10 (Figure 2) which is adapted
to be fixed to the engine and has, to this end, a plurality of peripheral bores adapted
to receive fixing bolts (not shown). Flange 10 is delimited by a flat surface 11 that
rests, in use, against a corresponding wall of the engine; a gasket (not shown) is
conveniently provided between the engine and surface 11.
[0015] Member 5 is provided with a coolant inlet aperture 12 and an EGR gas inlet aperture
13, both opening onto surface 11, so that they communicate with corresponding ports
of the engine coolant circuit and, respectively, EGR gas circuit upon assembly onto
the engine, with no need for additional connection tubings.
[0016] As can be clearly seen also from Figure 3, member 5 has a first lateral flange 14
for connection with EGR cooler and a second lateral flange 15 for connection with
a subassembly 16 including vacuum tank 8 and thermostat valve 9, as better described
hereinafter.
[0017] EGR gas inlet aperture 13 communicates with a through cavity 17 (Figure 4) extending
across member 5 and a tubular housing 18 integrally protruding from member 5 on the
side opposite to base flange 10 and enclosing a control assembly 19 of the EGR valve
2.
[0018] As can be clearly seen from the cross-section of Figure 4, EGR valve 2 is not a conventional,
drop-in valve provided with an housing of its own; rather, the housing of EGR valve
2 is constituted by member 5, which delimits a valve chamber 20 defined by a portion
of cavity 17. Valve chamber 20 communicates with an EGR valve outlet passage 21 internal
to member 5 and leading to bypass valve 4. Control assembly 19, which can be of any
known type, according to the present embodiment includes a disk shutter 22 which is
rigidly fixed to an end of an axially sliding stem 23. A spring 24 is housed in a
spring chamber 28 within tubular housing 18, and is axially compressed between a stop
member 25 fixed to an opposite end of stem 23 and a fixed shoulder 26, defined by
member 5 and located between valve chamber 20 and spring chamber 28, so as to bias
disk shutter 22 against an annular valve seat 27 axially interposed between gas inlet
aperture 13 and valve chamber 20.
[0019] EGR valve actuator 6 is assembled axially onto the tubular housing 18 and controls
the axial position of stem 23 so as to vary the EGR gas flow through a port formed
between valve seat 27 and disk shutter 22.
[0020] Bypass valve 4 (Figure 5, 6) includes a valve chamber 31 provided within member 5
and having an inlet port 32 communicating with EGR valve outlet passage 21, a first
outlet port 33 communicating with a cooler gas admission duct 34 and a second outlet
port 35 communicating with a gas exit duct 36, as well as with a cooler gas return
duct 37. Bypass valve 4 also includes a flap 38 that is pivotally mounted within valve
chamber 31 about a pivot 39, and may rotate between a first position (Figure 5), in
which second outlet port 35 is closed and inlet port 32 communicates with first outlet
port 33, and a second position (Figure 6), in which first outlet port 33 is closed
and inlet port 32 communicates with second outlet port 35. Cooler gas admission duct
34 and cooler gas return duct 37 open onto a front surface of flange 14 to form a
gas inlet chamber 40 and a gas outlet chamber 41 (Figure 3).
[0021] The position of flap 38 is controllable by means of vacuum-operated actuator 7 (Figure
1), having an axially reciprocating actuating rod 42 that is coupled to pivot 39 of
the valve flap 38 by means of a link 43 having one end rigidly connected to pivot
39 and one end articulated to rod 42.
[0022] Referring now to Figures 2, 3 and 9, member 5 internally defines a cooing circuit
including a main cooling cavity 46 which communicates with coolant inlet aperture
12 and extends adjacent to base flange 10 beside the EGR valve chamber 20 and below
bypass valve chamber 31 (Figure 3), so as to provide optimized cooling to both chambers.
Cooling cavity 46 is a blind cavity whose inlet 47 is closed, in use, by a cover 48
(only partially shown in Figure 3). Inlet 47 has thus no function but to allow cavity
46 to be obtained by introducing a movable core during casting.
[0023] Cooling cavity 46 serves as a coolant distribution chamber and communicates with
a plurality of ducts provided within member 5, namely a cooler admission duct 49 ending
with an opening 50 on first lateral flange 14 and a thermostat inlet duct 51 ending
into a thermostat chamber 52. Thermostat chamber 52 opens onto lateral flange 15 to
receive thermostat valve 9, as hereinafter explained. It is to be noted that ducts
49 and 51 significantly contribute to refrigerating member 5 and, therefore, EGR valve
2 and bypass valve 4.
[0024] EGR cooler (Figures 5 to 7) includes a housing 53 laterally delimiting a cooling
chamber 54 that is closed at both ends by a first and second head plates 55, 56 supporting
internal tubes collectively referenced 57. First head plate 55 also has a circular
coolant inlet opening 58 communicating with cooling chamber 54. Internal tubes 57
have their opposite ends engaging respective bores 59 in head plates 54, 55 and are
sealingly brazed therein. Internal tubes 57 form two different sets 57a, 57b; tubes
57a face gas inlet chamber 40, tubes 57b face gas outlet chamber 41. EGR cooler also
includes an end cup member 60 which is peripherally brazed to head plate 55 so as
to form a distribution chamber 61 connecting tubers 57a to tubes 57b.
[0025] EGR cooler 3 includes a mounting flange 62 which surrounds housing 53 at head plate
55, and is adapted to be mounted to first lateral flange 14, with an interposed gasket
not shown, so that coolant inlet opening 58 is connected to cooler admission duct
49, tubes 57a are connected to gas inlet chamber 40, and tubes 57b are connected to
gas outlet chamber 41.
[0026] Finally, EGR cooler 3 includes two coolant outlets 65, 66 provided on housing 53
and adapted to be connected to external devices using engine coolant, such as an oil
cooler and a cabin heater (both not shown). Coolant outlets 65, 66 conveniently include
quick connectors, rather than conventional spigots, so as to provide the utmost packaging
flexibility. The same module can thus be used in different applications, as layout
differences are dealt with by connecting pipes.
[0027] Figure 8 shows subassembly 16 in greater detail. Subassembly 16 includes a single-piece
plastics body 67 forming vacuum tank 8 and a coolant outlet pipe 68 adapted to be
connected to the vehicle radiator. Subassembly 16 includes a mounting flange 69 surrounding
an inlet 70 (Figure 8) of the outlet pipe 68; thermostat valve 9, per se known and
not described in detail, includes a control assembly 71 which is pre-assembled onto
the mounting flange 69 in a cantilever fashion, so as to be housed into thermostat
chamber 52 when the subassembly is mounted onto second lateral flange 15 of member
5.
[0028] Control assembly includes a shutter 72 cooperating with inlet 70 to define a variable
port. Shutter 72 is balanced between a closure force exerted by a biasing spring 73
and an opening force exerted by a heat-sensitive linear actuator 74, e.g. a wax actuator.
[0029] Operation of module 1 is as follows.
[0030] Coolant enters module 1 through inlet aperture 12 and reaches main cooling chamber
46. It is to be noted that chamber 46 receives the whole flow rate of coolant exiting
from the engine. Therefore, member 25 is cooled efficiently.
[0031] Coolant is splitted into two flows: a first flow is routed via duct 49 to refrigerating
chamber 54 of cooler 3, and hence to coolant outlets 65, 66.
[0032] The other portion of flow is routed via duct 51 to thermostat chamber 52. Flow rate
to outlet pipe 68, and thus to the vehicle radiator, is controlled by thermostat valve
9.
[0033] EGR gas enter module 1 through gas inlet aperture 13. Gas flow is controlled by EGR
valve 2, that is located on the "hot side", i.e. upstream, of the EGR cooler 3. Flow
rate is controlled as a function of engine operating parameters.
[0034] Past EGR valve 3, gases flow along valve outlet passage 21 and arrive to bypass valve
4. Depending on the engine operative conditions, EGR gases are either routed to EGR
cooler 3 or to gas exit duct 36 directly, thus bypassing EGR cooler 3.
[0035] In the first case gases flow through tubes 57a, distribution chamber 61, tubes 57b,
gas cooler return 37 and gas exit duct 36, which in use is connected to engine air
intake system (not shown).
[0036] An analysis of module 1 reveals the advantages brought by the present invention.
[0037] First of all, the module includes a stand-alone EGR valve 2 that is mounted directly
within member 5, i.e. without a casing of its own. This allows valve 2 to be cooled
very efficiently and thus to be located on the hot side of EGR cooler. Positioning
EGR valve 2 on the hot side of the cooler, when the engine layout so permits, allows
module 5 to be more compact with respect to the prior art, and thus cheaper. Also,
since EGR valve is subjected to hotter gases, the risk of sticking due to fouling
with residual combustion products is reduced.
[0038] Integrated subassembly 16, including vacuum tank 8, coolant outlet tube 68 and thermostat
valve 9, contributes to reducing assembly costs and to making the module more compact
and cheaper.
[0039] The use of quick connectors at coolant outlets 65, 66 makes module 1 more flexible
and adaptable to different configurations of the engine by "personalizing" the coolant
connecting pipes.
[0040] Figure 10 discloses a different embodiment of EGR cooler 103, that is described hereinafter
using the same numerals as for cooler 3 to reference like parts. In cooler 103, head
plate 56 is obtained in a single piece together with lateral housing 53. At the opposite
end of the cooler, housing 53 integrally includes an outwardly bent planar flange
104, onto which head plate 55 is brazed. Housing 53 also has a lateral bulge 105 adjacent
to flange 104. Head plate 55 is stamped so as to form a short inlet sleeve 106 that
is axially aligned with bulge 105; in this manner, coolant inlet does not subtract
any useful volume inside cooling chamber 54, that can therefore be totally occupied
by internal tubes 57. Sleeve 106 sealingly engages an OR sealing 107 provided within
opening 50 of flange 14.
[0041] Flange 62 surrounds housing 53 and backs flange 104 on the side opposite to flange
104 to increase the mechanical strength of the coupling; in this manner, there is
no contact between flange 62 and member 5 and flange 62 can be made of carbon steel
or aluminium or sintered material, rather than stainless steel, and thus be cheaper.
To allow flange 62 to be mounted without interfering with outlets 65, 66, flange 62
can be made in two parts connected to one another by means of dovetail joints 108.
[0042] Tubes 57a, 57b, end cup member 60 and coolant outlets 65, 66 are identical to corresponding
parts described with reference to cooler 3.
[0043] Cooler 103, that is particularly compact and efficient, can obviously be used in
any different applications requiring a double-pass cooler.
[0044] Clearly, variants and modifications can be brought to the module as herein described
without departing from the scope of the claims.
[0045] In particular, the EGR valve actuator can be of any type and can be assembled differently
onto interface member 5. Furthermore, the bypass valve actuator can be of any type
other than a vacuum-operated actuator, e.g. an electrical actuator or a pressure-operated
actuator.
1. An EGR/cooling integrated module (1) for an IC engine including an interface member
(5) adapted to be mounted to the engine, and further including an EGR valve (2), an
EGR cooler (3) and a bypass valve (4) carried and interconnected by the interface
member (5), wherein
• the interface member (5) includes a coolant inlet aperture (12) and an EGR gas inlet
aperture (13) adapted to be connected directly to corresponding ports of said engine
upon assembling said module (1) to said engine,
• the EGR valve (2) is located on the hot side of the EGR cooler (3) and that the
interface member (5) defines a housing of said EGR valve (2) and a cooling circuit
(46, 49, 51) for cooling said EGR valve (2),
• the EGR valve (2) is housed in a cavity (17) of said interface member (5), and includes
a shutter (22) and a valve seat (27) provided in said cavity (17) between a valve
chamber (20) defined by said cavity (17) and the EGR gas inlet (13),
• said cooling circuit (46, 49, 51) includes a cooling cavity (46) provided within
said interface member (5) and communicating with the coolant inlet aperture (12),
in such a way that the cooling cavity (46) receives the whole flow rate of coolant
exiting from the engine, said cooling cavity (46) being adjacent to said EGR valve
(2),
• said bypass valve (4) includes a bypass valve chamber (31) having an inlet port
(32) connected to said EGR valve chamber (20) via an EGR valve outlet passage (21),
a first outlet port (33) communicating with a cooler gas admission duct (34) and a
second outlet port (35) communicating with a gas exit duct (36) and as well as with
a cooler gas return duct (37); said bypass valve chamber (31), EGR valve outlet passage
(21), cooler gas admission duct (34), gas exit duct (36) and cooler gas return duct
(37) being provided within said interface member (5); and, wherein the cooling cavity
(46) is adapted for cooling the EGR valve chamber (20) and the bypass valve chamber
(31).
2. A module as claimed in claim 1, characterised in that said cavity (17) of said interface member (5) forms a spring chamber (28) separated
from said valve chamber (20) by an intermediate shoulder (26); said EGR valve (2)
including a stem (23) rigidly connected to said shutter (22), and a spring (24) located
inside said spring chamber (28) and acting between said shoulder (26) and a stop member
(25) fixed to the stem (23) so as to bias said shutter (22) against said valve seat
(27).
3. A module as claimed in claim 2, characterised in that said spring chamber (28) is formed within a tubular housing (18) integrally protruding
from said interface member (5), said cavity (17) of said interface member (5) being
constituted by a through cavity extending through said interface member (5) and said
tubular housing (18).
4. A module as claimed in claim 3, characterised in that said interface member (5) includes a first duct (49) connecting said cooling cavity
(46) to said EGR cooler (3) and a second duct (51) connecting said cooling cavity
(46) to a coolant exit (68).
5. A module as claimed in any of the preceding claims, characterised by including a subassembly (16) including a vacuum tank (8) for a vacuum-operated bypass
valve actuator (7) and a thermostat valve (9).
6. A module as claimed in claim 4 and 5, characterised in that said subassembly (16) includes a coolant outlet pipe (68) formed in a single piece
with said vacuum tank (8) and defining said coolant exit.
7. A module as claimed in claim 6, characterised in that said subassembly (16) includes a connecting flange (69) for connection with said
interface member (5), said thermostat valve (9) being carried by said connecting flange
(69) and including a shutter (72) cooperating with an inlet (70) of said coolant outlet
pipe (68) formed in said connecting flange (69), said thermostat valve (9) extending
within a thermostat chamber (52) defined by said second duct (51).
8. A module as claimed in any of the preceding claims, characterised in that said EGR cooler (3) is a double-pass cooler.
9. A module as claimed in any of the preceding claims, characterised in that said EGR cooler includes at least a coolant exit (65, 66) for connection with an
external device.
10. A module as claimed in claim 9, characterised in that said coolant exit (65, 66) includes a quick coupling.
11. A module as claimed in any of claims 8 to 10, characterised in that said EGR cooler (3) includes an outer housing (53) defining a cooling chamber (54),
a first and second head plates (55, 56) and a plurality of internal tubes (57) fixed
to said head plates (55, 56), said outer housing (53) defining integrally said first
head plate (56) and a connecting flange (104) for connection with said second head
plate (55), said second head plate (55) being interposed between said connecting flange
(105) and said interface member (5).
12. A module as claimed in claim 11, characterised in that said EGR cooler (3) includes a backing flange (62) axially contacting said connecting
flange (104) on the side opposite to said second head plate (55).
13. A module as claimed in claim 11, characterised in that said housing (53) formed a lateral bulge (105), and that said first head plate (55)
forms a coolant inlet sleeve (106) axially facing said bulge (105).
1. Integriertes AGR/Kühl-Modul (1) für einen Verbrennungsmotor, das ein Schnittstellenelement
(5) enthält, das zur Anbringung an dem Motor eingerichtet ist, und das des Weiteren
ein AGR-Ventil (2), einen AGR-Kühler (3) sowie ein Umgehungs-Ventil (4) enthält, die
von dem Schnittstellenelement (5) getragen werden und über dieses miteinander verbunden
sind, wobei
• das Schnittstellenelement (5) eine Kühlmittel-Einlassöffnung (12) sowie eine AGR-Gas-Einlassöffnung
(13) enthält, die so eingerichtet sind, dass sie nach dem Anbringen des Moduls (1)
an dem Motor direkt mit entsprechenden Anschlüssen des Motors verbunden sind,
• sich das AGR-Ventil (2) an der Heißgasseite des EGR-Kühlers (3) befindet und das
Schnittstellenelement (5) ein Gehäuse des AGR-Ventils (2) sowie einen Kühlkreis (46,
49, 51) zum Kühlen des AGR-Ventils (2) bildet,
• das AGR-Ventil (2) in einem Hohlraum (17) des Schnittstellenelementes (5) aufgenommen
ist und einen Verschluss (22) sowie einen Ventilsitz (27) enthält, die in dem Hohlraum
(17) zwischen einer durch den Hohlraum (17) gebildeten Ventilkammer (20) und dem AGR-Gas-Einlass
(13) vorhanden sind,
• der Kühlkreis (46, 49, 51) einen Kühl-Hohlraum (46) enthält, der im Inneren des
Schnittstellenelementes (5) vorhanden ist und so mit der Kühlmittel-Einlassöffnung
(12) in Verbindung steht, dass der Kühl-Hohlraum (46) den gesamten Durchfluss von
Kühlmittel aufnimmt, das aus dem Motor austritt, wobei der Kühl-Hohlraum (46) an das
AGR-Ventil (2) angrenzt,
• das Umgehungs-Ventil (4) eine Umgehungs-Ventilkammer, (31) enthält, die einen Einlassanschluss
(32), der mit der AGR-Ventilkammer (20) über einen AGR-Ventil-Auslasskanal (21) verbunden
ist, einen ersten Auslassanschluss (33), der in Verbindung mit einer Kühler-Gaseintrittsleitung(34)
steht, sowie einen zweiten Auslassanschluss (35) aufweist, der mit einer Gasaustrittsleitung
(36) sowie mit einer Kühler-Gasrückführleitung (37) in Verbindung steht, wobei die
Umgehungs-Ventilkammer (31), der AGR-Ventil-Auslasskanal (21), die Kühler-Gaseintrittsleitung
(34), die Gasaustrittsleitung (36) und die Kühler-Gasrückführleitung (37) im Inneren
des Schnittstellenelementes (5) vorhanden sind und der Kühl-Hohlraum (46) zum Kühlen
der AGR-Ventilkammer (20) und der Umgehungs-Ventilkammer (31) eingerichtet ist.
2. Modul nach Anspruch 1, dadurch gekennzeichnet, dass der Hohlraum (17) des Schnittstellenelementes (5) eine Feder-Kammer (28) bildet,
die von der VentilKammer (20) durch einen Zwischenabsatz (26) getrennt ist, wobei
das AGR-Ventil (2) einen Schaft (23), der starr mit dem Verschluss (22) verbunden
ist, sowie eine Feder (24) enthält, die sich im Inneren der Feder-Kammer (28) befindet
und zwischen dem Absatz (26) und einem an dem Schaft (23) befestigten Anschlagelement
(25) wirkt, um so den Verschluss (22) an den Ventilsitz (27) zu spannen.
3. Modul nach Anspruch 2, dadurch gekennzeichnet, dass die Feder-Kammer (28) im Inneren eines röhrenförmigen Gehäuses (18) ausgebildet ist,
das integral von dem Schnittstellenelement (5) vorsteht, und der Hohlraum (17) des
Schnittstellenelementes (5) von einem durchgehenden Hohlraum gebildet wird, der sich
durch das Schnittstellenelement (5) und das röhrenförmige Gehäuse (18) hindurch erstreckt.
4. Modul nach Anspruch 3, dadurch gekennzeichnet, dass das Schnittstellenelement (5) eine erste Leitung (49), die den Kühl-Hohlraum (46)
mit dem AGR-Kühler (3) verbindet, sowie eine zweite Leitung (51) enthält, die den
Kühl-Hohlraum (46) mit einem Kühlmittel-Austritt (68) verbindet.
5. Modul nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass es eine Teilbaugruppe (16) enthält, die einen Vakuumbehälter (8) für ein vakuumbetriebenes
Umgehungs-Ventil-Betätigungselement (7) und ein Thermostat-Ventil (9) enthält.
6. Modul nach Anspruch 4 und 5, dadurch gekennzeichnet, dass die Teilbaugruppe (16) ein Kühlmittel-Auslassrohr (68) enthält, das aus einem Stück
mit dem Vakuumbehälter (8) ausgebildet ist und den Kühlmittel-Austritt bildet.
7. Modul nach Anspruch 6, dadurch gekennzeichnet, dass die Teilbaugruppe (16) einen Verbindungsflansch (69) zur Verbindung mit dem Schnittstellenelement
(5) enthält, wobei das Thermostat-Ventil (9) von dem Verbindungsflansch (69) getragen
wird und einen Verschluss (72) enthält, der mit einem Einlass (70) des Kühlmittel-Auslassrohrs
(68) zusammenwirkt, der in dem Verbindungsflansch (69) ausgebildet ist, und sich das
Thermostat-Ventil (69) im Inneren einer Thermostat-Kammer (52) erstreckt, die durch
die zweite Leitung (51) gebildet wird.
8. Modul nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass der AGR-Kühler (3) ein Kühler mit zweifachem Durchlauf ist.
9. Modul nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass der AGR-Kühler wenigstens einen Kühlmittel-Austritt (65, 66) zur Verbindung mit einer
externen Einrichtung enthält.
10. Modul nach Anspruch 9, dadurch gekennzeichnet, dass der Kühlmittel-Austritt (65, 66) eine Schnellkupplung enthält.
11. Modul nach einem der Ansprüche 8 bis 10, dadurch gekennzeichnet, dass der AGR-Kühler (3) ein äußeres Gehäuse (53), das eine Kühlkammer (54) bildet, eine
erste und eine zweite Kopfplatte (55, 56) sowie eine Vielzahl innerer Röhren (57)
enthält, die an den Kopfplatten (55, 56) befestigt sind, das äußere Gehäuse (53) integral
die erste Kopfplatte (56) sowie einen Verbindungsflansch (104) zur Verbindung mit
der zweiten Kopfplatte (55) bildet und die zweite Kopfplatte (55) zwischen dem Verbindungsflansch
(105) und dem Schnittstellenelement (5) angeordnet ist.
12. Modul nach Anspruch 11, dadurch gekennzeichnet, dass der AGR-Kühler (3) einen Trageflansch (62) enthält, der mit dem Verbindungsflansch
(104) an der der zweiten Kopfplatte (55) gegenüberliegenden Seite axial in Kontakt
ist.
13. Modul nach Anspruch 11, dadurch gekennzeichnet, dass das Gehäuse (53) eine seitliche Auswölbung (105) bildet und dass die erste Kopfplatte
(55) eine Kühlmittel-Einlassmuffe (106) bildet, die der Aufwölbung (105) axial zugewandt
ist.
1. Module intégré d'EGR/refroidissement (1) pour un moteur IC comprenant un élément d'interface
(5) adapté de façon à être monté sur le moteur, et comprenant en outre une soupape
EGR (2), un dispositif de refroidissement EGR (3) et une soupape de dérivation (4)
supportée et interconnectée par l'élément d'interface (5), dans lequel :
- l'élément d'interface (5) comprend une ouverture d'entrée de fluide de refroidissement
(12) et une ouverture d'entrée des gaz EGR (13) adaptées de façon à être connectées
directement à des orifices correspondants dudit moteur lors de l'assemblage dudit
module (1) sur le moteur ;
- la soupape EGR (2) se situe du côté chaud du dispositif de refroidissement EGR (3)
et l'élément d'interface (5) définit un logement de ladite soupape EGR (2) et un circuit
de refroidissement (46, 49, 51) destiné à refroidir ladite soupape EGR (2) ;
- la soupape EGR (2) est logée dans une cavité (17) dudit élément d'interface (5),
et comprend un volet (22) et un siège de soupape (27) disposés dans ladite cavité
(17) entre une chambre de soupape (20) définie par ladite cavité (17) et l'entrée
des gaz EGR (13) ;
- ledit circuit de refroidissement (46, 49, 51) comprend une cavité de refroidissement
(46) disposée à l'intérieur dudit élément d'interface (5) et en communication avec
l'ouverture d'entrée de fluide de refroidissement (12), de telle manière que la cavité
de refroidissement (46) reçoive la totalité du débit de fluide de refroidissement
qui sort du moteur, ladite cavité de refroidissement (46) étant adjacente à ladite
soupape EGR (2) ;
- ladite soupape de dérivation (4) comprend une chambre de soupape de dérivation (31)
qui présente un orifice d'entrée (32) connecté à ladite chambre de soupape EGR (20)
par l'intermédiaire d'un passage de sortie de soupape EGR (21), un premier orifice
de sortie (33) en communication avec un conduit d'admission des gaz du dispositif
de refroidissement (34) et un second orifice de sortie (35) en communication avec
un conduit de sortie des gaz (36) et aussi avec un conduit de retour des gaz du dispositif
de refroidissement (37) ; ladite chambre de soupape de dérivation (31), ledit passage
de sortie de soupape EGR (21), ledit conduit d'admission des gaz du dispositif de
refroidissement (34), ledit conduit de sortie des gaz (36) et ledit conduit de retour
des gaz du dispositif de refroidissement (37) étant disposés à l'intérieur dudit élément
d'interface (5) ; et, dans lequel la cavité de refroidissement (46) est adaptée de
façon à refroidir la chambre de soupape EGR (20) et la chambre de soupape de dérivation
(31).
2. Module selon la revendication 1, caractérisé en ce que ladite cavité (17) dudit élément d'interface (5) forme une chambre à ressort (28)
séparée de ladite chambre de soupape (20) par un épaulement intermédiaire (26) ; ladite
soupape EGR (2) comprenant une tige (23) connectée de manière rigide audit volet (22),
et un ressort (24) qui se situe à l'intérieur de ladite chambre à ressort (28) et
qui agit entre ledit épaulement (26) et un élément d'arrêt (25) fixé sur la tige (23)
de façon à solliciter ledit volet (22) contre ledit siège de soupape (27).
3. Module selon la revendication 2, caractérisé en ce que ladite chambre à ressort (28) est formée à l'intérieur d'un logement tubulaire (18)
qui fait saillie d'une pièce à partir dudit élément d'interface (5), ladite cavité
(17) dudit élément d'interface (5) étant constituée par une cavité traversante qui
s'étend à travers ledit élément d'interface (5) et ledit logement tubulaire (18).
4. Module selon la revendication 3, caractérisé en ce que ledit élément d'interface (5) comprend un premier conduit (49) qui relie ladite cavité
de refroidissement (46) audit dispositif de refroidissement EGR (3), et un second
conduit (51) qui relie ladite cavité de refroidissement (46) à une sortie du fluide
de refroidissement (68).
5. Module selon l'une quelconque des revendications précédentes, caractérisé par le fait qu'il comprend un sous-ensemble (16) qui comprend un réservoir à vide (8) destiné à un
actionneur de soupape de dérivation actionnée par dépression (7) et une soupape de
thermostat (9).
6. Module selon la revendication 4 et la revendication 5, caractérisé en ce que ledit sous-ensemble (16) comprend un tube de sortie de fluide de refroidissement
(68) formé d'une seule pièce avec ledit réservoir à vide (8) et qui définit ladite
sortie de fluide de refroidissement.
7. Module selon la revendication 6, caractérisé en ce que ledit sous-ensemble (16) comprend une bride de connexion (69) destinée à une connexion
avec ledit élément d'interface (5), ladite soupape de thermostat (9) étant portée
par ladite bride de connexion (69) et comprenant un volet (72) qui coopère avec une
entrée (70) dudit tube de sortie de fluide de refroidissement (68) formé dans ladite
bride de connexion (69), ladite soupape de thermostat (9) s'étendant à l'intérieur
d'une chambre de thermostat (52) définie par ledit second conduit (51).
8. Module selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit dispositif de refroidissement EGR (3) est un dispositif de refroidissement
à double passage.
9. Module selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit dispositif de refroidissement EGR comprend au moins une sortie de fluide de
refroidissement (65, 66) destinée à être connectée à un dispositif extérieur.
10. Module selon la revendication 9, caractérisé en ce que ladite sortie de fluide de refroidissement (65, 66) comprend un raccord rapide.
11. Module selon l'une quelconque des revendications 8 à 10, caractérisé en ce que ledit dispositif de refroidissement EGR (3) comprend un logement extérieur (53) qui
définit une chambre de refroidissement (54), des première et seconde plaques frontales
(55, 56) et une pluralité de tubes intérieurs (57) fixés sur lesdites plaques frontales
(55, 56), ledit logement extérieur (53) définissant d'une pièce ladite première plaque
frontale (56) et une bride de connexion (104) destinée à une connexion avec ladite
seconde plaque frontale (55), ladite seconde plaque frontale (55) étant interposée
entre ladite bride de connexion (105) et ledit élément d'interface (5).
12. Module selon la revendication 11, caractérisé en ce que ledit dispositif de refroidissement EGR (3) comprend une bride de support (62) qui
entre en contact de manière axiale avec ladite bride de connexion (104) sur le côté
opposé à ladite seconde plaque frontale (55).
13. Module selon la revendication 11, caractérisé en ce que ledit logement (53) forme un renflement latéral (105), et en ce que ladite première plaque frontale (55) forme un manchon d'entrée de fluide de refroidissement
(106) qui fait face de manière axiale audit renflement (105).