Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
  • F01P7/00—Controlling of coolant flow
  • F01P7/02—Controlling of coolant flow the coolant being cooling-air
  • F01P7/06—Controlling of coolant flow the coolant being cooling-air by varying blade pitch
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
  • F02M26/23—Layout, e.g. schematics
  • F02M26/25—Layout, e.g. schematics with coolers having bypasses
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
  • F02M26/29—Constructional details of the coolers, e.g. pipes, plates, ribs, insulation or materials
  • F02M26/30—Connections of coolers to other devices, e.g. to valves, heaters, compressors or filters; Coolers characterised by their location on the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/51—EGR valves combined with other devices, e.g. with intake valves or compressors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
  • F01P11/00—Component parts, details, or accessories not provided for in, or of interest apart from, groups F01P1/00 - F01P9/00
  • F01P11/04—Arrangements of liquid pipes or hoses
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
  • F02M26/23—Layout, e.g. schematics
  • F02M26/25—Layout, e.g. schematics with coolers having bypasses
  • F02M26/26—Layout, e.g. schematics with coolers having bypasses characterised by details of the bypass valve
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/52—Systems for actuating EGR valves
  • F02M26/53—Systems for actuating EGR valves using electric actuators, e.g. solenoids

Definitions

• the present invention relates to an EGR/cooling integrated module for an IC engine.
• 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.
• 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.
• 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.
• FIG. 1 is a front view of an EGR/cooling integrated module in accordance with the present invention.
• 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
• FIG. 7 is a perspective view of an EGR cooler of the module which is part of the integrated module of the invention.
• FIG. 8 is a perspective view of a thermostat/vacuum tank subassembly which is part of the integrated module of the invention.
• 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.
• module 1 designates as a whole an EGR/cooling integrated module in accordance with the present invention (hereinafter “module 1".
• 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).
• 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.
• 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 fiat 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• FIG. 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.
• 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. Operation of module 1 is as follows.
• 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. 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.
• 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.
• 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.
• 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.
• FIG. 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.
• head plate 56 is obtained in a single piece together with lateral housing 53.
• 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.
• 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.
• flange 62 can be made in two parts connected to one another by means of dovetail joints 108.
• the EGR valve actuator can be of any type and can be assembled differently onto interface member 5.
• 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.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Exhaust-Gas Circulating Devices (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

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• 2007
  • 2007-10-09 ES ES200702654A patent/ES2299405B1/es not_active Expired - Fee Related
• 2008
  • 2008-10-08 ES ES08838445.8T patent/ES2507565T3/es active Active
  • 2008-10-08 WO PCT/EP2008/063496 patent/WO2009047278A1/en active Application Filing
  • 2008-10-08 PL PL08838445T patent/PL2215345T3/pl unknown
  • 2008-10-08 EP EP08838445.8A patent/EP2215345B1/de active Active

Non-Patent Citations (1)

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