The present invention relates to the field of motor vehicle parts and equipment, more particularly the air inlet systems of the internal combustion engines of such vehicles, and relates to an integrated air inlet module, a motor vehicle comprising such a module and a process for manufacturing such a module.
At present, the space available under the engine bonnet of vehicles is ever more restricted, particularly around the engine block, favouring integration of the functions to be achieved in order to reduce size, while continuing to maintain their quality and operational life, on which the reliability of the vehicle's operation depends.
In addition, in terms of the development and manufacture of internal combustion engine vehicles, the present trend is no longer think to in terms of isolated elements, namely components or parts, but in terms of assemblies, units or modules, each fulfilling an overall function or several interdependent elementary functions.
This is the case in particular for the overall air inlet function, whether the air is turbocompressed or not, which usually incorporates the function of admitting fresh air and the function of recycling or reinjecting at least part of the exhaust gases, in a way that can be regulated and controlled.
An air inlet module that combines these two functions normally includes, in one structural unit, on the one hand, an inlet manifold or distributor with a supply conduit, on the other hand, a circuit for the controlled reinjection and mixing of exhaust gases in the fresh air admitted by the manifold and, finally, a gas/liquid heat exchanger designed to cool the exhaust gases before they are mixed with the possibly turbocompressed, air admitted, said exchanger being composed substantially of several exhaust gas circulation manifolds mounted in a hollow container forming a tank and receiving a cooling liquid circulating around said circulation manifolds. Different embodiments of such an air inlet module are already known, but these known embodiments have, however, drawbacks and limitations preventing a satisfactory response to the demands made.
Among these limitations can be mentioned, in particular, the difficulty of manufacture, resulting from the very large number of elementary components to be assembled, sensitivity to vibrations and a not inconsiderable excess weight due to these numerous assemblies, and the resulting large size.
Thus, through document EP-A-1 375 896, a module of the aforementioned type is known, incorporating a plate for distributing, mixing and conveying the different fluid gases (fresh air and exhaust gases), in which circulation channels are provided.
Nevertheless, this module still has numerous assembly zones for the many different constituent parts and is large in size.
The object of the present invention is, in particular, to overcome the aforementioned drawbacks and limitations, whilst also optimising the materials used in terms of cost.
Accordingly, it relates to an air inlet module of the aforementioned type, characterised in that it consists of a sealed assembly of at most four parts, namely, a first part made of a plastic material comprising the inlet manifold, the outlet manifolds thereof, a portion of the supply conduit opening into said inlet manifold, and a hollow body forming an open container and part of the exchanger tank, a second part comprising the many circulation manifolds and a support body for positioning and assembling said manifolds in the tank to form the exchanger, a third part made of a metallic material of which one portion forms a cover for the hollow open container, comprising a plurality of conduit portions forming at least part of the exhaust gas circulation circuit incorporating, conditionally if applicable, the circulation manifolds conveying the exhaust gases in the inlet manifold or in the conduit supplying said manifold, and a fourth part, optionally formed in a single piece with the first part, made up of a hollow body forming an open container and part of the exchanger tank.
The invention will be better understood, using the description below, which relates to two preferred embodiments, given as non-limiting examples, and explained with reference to the accompanying diagrammatic drawings, in which:
FIGS. 1 to 3 are views in perspective from different angles of an air inlet module according to a first embodiment of the invention, formed by assembling three parts;
FIGS. 4 to 8 are views in side, front and rear elevation of the module in FIGS. 1 to 3.
The Figures in the accompanying drawings show an air inlet module 1 incorporating, in one structural unit, on the one hand, an inlet manifold or distributor 2 with a supply conduit 3, on the other hand, a circuit 3″, 13, 13′, 13″, 14, 16 for the controlled reinjection and mixing of exhaust gases in the fresh air aspirated by the manifold 2 and, finally, a gas/liquid heat exchanger 4 designed to cool the exhaust gases before they are mixed with the aspirated fresh, and possibly turbocompressed, air, said exchanger 4 being made up substantially of many exhaust gas circulation manifolds 5 mounted in a hollow container 6 forming a tank and receiving a cooling liquid circulating around said circulation manifolds 5.
According to the invention, this module 1 consists of a sealed assembly of at most four constituent parts 7, 8, 9 and 11, namely, a first part 7 made of a plastic material comprising the inlet manifold 2, the outlet manifolds 10 thereof, a portion 3′ of the supply conduit 3 opening into said inlet manifold 2, and a hollow body 11 forming an open container and part of the tank 6 of the exchanger 4, a second part 8 comprising the large number of circulation manifolds 5 and a support body 12 for positioning and assembling said manifolds 5 in the tank 6 to form the exchanger 4, a third part 9 made of a metallic material of which one portion forms a cover 9′ for the hollow open container 11 and comprising a plurality of conduit portions 13, 13′, 13″ forming at least one part of a circulation circuit for the exhaust gases incorporating, conditionally if applicable, the circulation manifolds 5 and conveying the exhaust gases in the inlet manifold 2 or in the conduit 3 supplying the inlet manifold, and, a fourth part 11, optionally formed in a single piece with the first part 7, made up of a hollow body forming an open container and part of the tank 6 of the exchanger 4.
Thus, the module 1 according to the invention comprises only four parts at most to be assembled, each of these parts being produced previously in one or more operational phases (preferably in one or two), comprising elements, parts or components of several functional assemblies of said module 1 and consisting of a material of optimised cost, while being suited to its function.
The portion forming a cover 9′ of the third part 9 will thus close the hollow body 11 (at least on the side concerned) to form the tank 6.
The material forming the first part 7 and the fourth part 11 may consist of a thermoplastic material, optionally reinforced, and this part may be achieved by assembly by vibration welding of a plurality of elementary parts produced by injection moulding.
The material forming the third part 9, and the second part 8, may consist of an alloy based on aluminium or a similar metal resistant to the usual temperatures of exhaust gases.
According to a first embodiment, shown in FIGS. 1 to 17, the air inlet module 1 may be formed by the assembly of only three parts 7, 8 and 9, the fourth part 11 being an integral part and formed in a single piece or preassembled with the first part 7.
According to a second embodiment, shown in
Apart from this additional separation between the first and fourth parts, in the module according to the second embodiment the composition and structure of its constituent parts are very similar and the forms are substantially identical to the parts forming the module according to the first embodiment.
The description that follows of the elements and components of the different parts therefore applies to both embodiments, unless otherwise indicated.
Advantageously, and in order to achieve an integrated module 1 that is totally functional both regarding its structure and its command and control, the third part 9 may also comprise, mounted on and/or partly in it, on the one hand a component 15 for regulating the throughput of the aspirated air flow and its actuating device 15′, and, on the other hand, a component 16 for regulating the quantity of exhaust gas reinjected into the aspirated air, with its actuating device 16′, so as to form, together with the circulation circuit 5, 13, 13′, 13″, the circuit for the controlled reinjection and mixing the exhaust gas/aspirated air.
According to a characteristic of the invention that allows the temperature of the exhaust gases to be regulated before they are reinjected, the conduit portions 13, 13′, 13″ also define a by-pass channel, allowing the flow of exhaust gases to by-pass or short-circuit the circulation manifolds 5, the third part 9 comprises, in addition, an exhaust gas flow by-pass or diversion component 14 of which the position determines the circulation of these gases through the manifolds 5 or through the by-pass channel, the actuating device 14′ of this component 14 being preferably also mounted on and/or partially in said third constituent part 9.
According to another characteristic of the invention, the third constituent part 9 may also incorporate an additional portion 3″ of the supply conduit 3 opening into the inlet manifold 2, the exhaust gas circulation circuit 5, 13, 13′, 13″ opening into said additional portion 3″, preferably passing or traversing a component 16 regulating the quantity of exhaust gas reinjected into the aspirated air.
According to a preferred embodiment of the invention, shown more particularly in
For the second embodiment, two assemblies must be produced, namely between the first and third parts 7 and 9, on the one hand, and between the fourth and third parts 11 and 9, on the other hand (for example in the region of the opposing grommets or flanges 26).
To reduce their size and make them easier to supply, by grouping the inlet and outlet interfaces geographically, the circulation manifolds 5 advantageously define U-shaped circulation paths and are inserted or formed on a support body 12 of an openwork plate structure with a peripheral mounting frame 12′, said openwork plate 12 being exposed to the flow of exhaust gases, when the controlled by-pass component 14 is in a suitable position, such that a looped circulation is established in said manifolds 5 with the inlets and outlets of the circulation paths in the region of said plate 12. The U-shaped structure of the paths may result for example from forming each manifold 5 in a U shape, with its inlet and outlet situated in the region of the openwork plate 12, each in a specific zone thereof grouping together respectively, one, the inlets of the various manifolds 5 and, the other, the outlets thereof.
In a variant, as shown in
The mounting frame 12′ may be partially received in a shoulder 11′″ formed in the region of the edge 11″ of the opening 11′ of the hollow open body 11, with a sealing joint 25, for example doughnut-shaped, being interposed.
According to another characteristic of the invention, and as shown in the Figures of the accompanying drawings, more particularly in
Advantageously, the circulation channel 18 consists of a groove extending peripherally in the region of the face of the third part 9 resting on the peripheral mounting frame 12′ of the support body 12 of the second part 8, following the contour of said frame 12′ and being situated opposite traversing openings 12″ arranged therein, said groove 18 being delimited by two parallel circumferential wall portions 19 and 19′ of which the internal wall 19 also delimits the internal volume 20 of the circulation circuit 13, 13′, 13″ for the exhaust gases in contact with the inlets 5′ and the outlets 5″ of the circulation manifolds 5 (see
By extending over the peripheral contour of the portion forming a cover, this groove 18 will participate in the cooling of the third part 9, thus limiting dimensional variations due to temperature changes, and in that of the by-pass component 14 directly exposed to the hot exhaust gas flow.
Preferably, the first part 7 and the third part 9 are assembled, in a sealed manner, on the one hand, in the region of the two portions 3′ and 3″ of the supply conduit 3 opening into the inlet manifold 2 and, on the other hand, in the region of the edge 11″ of the opening 11′ of the hollow open container 11 and of the portion forming a cover 9′, with a peripheral mounting frame 12′ of the support body 12 of the second part 8 being interposed between said first and third parts, the assembly planes P and P′ of the two assembly zones being parallel to each other, and if applicable merged.
Thus, only two assembly zones are needed to make up the module 1 from the three constituent parts 7, 8 and 9, or from the four constituent parts 7, 8, 9 and 11.
The sealed joining zones between the support body 12 (frame) and the portion forming a cover 9′ advantageously have flat surfaces and, in association with the sealed joint between said support body 12 (frame) and the hollow open container 11, allow two fluidic circulation circuits separated in a sealed manner to be formed in this container, one for exhaust gases and the other for the cooling liquid.
According to a practical variation that is advantageous in terms of size in certain configurations, the hollow open container 11 forming part of the exchanger 4 and of the reception tank 6 for the exhaust gas circulation manifolds 5 thereof has a cylindrical, circular-section structure, the inlet manifold 2 having an elongated chamber 2′, with the outlet manifolds 10 and the supply conduit 3 opening laterally through opposite longitudinal sides in this chamber 2′, and the longitudinal axes of the hollow open container 11, of the chamber 2′ of inlet manifold 2 and of a rectilinear part of the supply conduit 3 being substantially parallel.
To confer greater rigidity to the first part 7, provision can be made for the hollow open cylindrical container 11 forming part of the exchanger 4 and incorporated in said part 7 to comprise external ribs 21 to provide rigidity, these ribs 21 being situated in spaced parallel planes substantially perpendicular to the axis of said container 11 and extending to the wall of the chamber 2′ of the inlet manifold 2 and to the portion of supply conduit 3′ forming part of the first part 7.
To connect the module 1 in situ, fixing flanges 22, formed in a single piece with the first part 7, are associated with outlet manifolds 10 and at least one, preferably several, fixing flange(s) 23, formed in a single piece with the third part 9, is (are) arranged around the inlet of the conduit 13 conveying the exhaust gases in the circulation circuit formed in the third part 9, additional fixing flanges 22′ being formed on the fourth part 11, if this fourth part is not structurally incorporated in said first part 7.
The flanges 22′ may serve either to connect part 11 to part 7, or to directly connect said part 11 with the support body of the inlet module 1.
The invention also relates to an internal combustion engine vehicle, characterised in that it comprises an air inlet module 1 incorporated as described above, preferably fixed directly on the engine block.
Preferably, the module 1 is connected on the engine block in the region of the first and third parts 7 and 9, with tightening parts of a deformable material being interposed, preferably resiliently, in the region of fixing points between the first part 7 and said engine block.
Finally, the invention also relates to a process for manufacturing an air inlet module 1 of the type described above, characterised in that it consists in manufacturing separately the first second and third parts 7, 8 and 9, in introducing and adjusting the second part 8 in the first part 7, in such a way that the support body 12 rests peripherally on and partly in the edge 11″ of the opening 11′ of the hollow open container 11 and positions the second part 8 in this container 11, and then in assembling with a tightened seal the third part 9 with the first part 7 in the region of the two portions 3′ and 3″ of the supply conduit 3 and in the region of the opening 11′ of the hollow open container 11, with the support body 12 being interposed and pinched and the hollow open container 11 being closed and sealed with the portion forming a cover 9′.
In a variant, and according to the second embodiment of the inlet module, the aforementioned process may also consist in manufacturing separately the first, second, third and fourth parts 7, 8, 9 and 11, introducing and adjusting the second part 8 in the fourth part 11, in such a way that the support body 12 rests peripherally on and partially in the edge 11″ of the opening 11′ of the hollow open container 11 and positions the second part 8 in this container 11, and then in assembling with a tight seal the third part 9, on the one hand, with the first part 7 in the region of two portions 3′ and 3″ forming the supply conduit 3 and, on the other hand, with the fourth part 11 in the region of the opening 11′ of the hollow open container 11, with the support body 12 being interposed and pinched and the hollow open container 11 being sealed and closed with the portion forming a cover 9′.
Preferably, provision can be made to supply a third part 9 comprising, mounted on it and/or partially in it, on the one hand, a component 15 for regulating the throughput of the aspirated air flow and its actuating device 15′, on the other hand, a component 16 for regulating the quantity of exhaust gas reinjected in the aspirated air, with its actuating device 16′, so as to form, together with the circulation circuit 5, 13, 13′, 13″, the controlled reinjection and mixing circuit and, finally, the actuating device 14′ of the exhaust gas flow by-pass component 14.
The base body of this third part 9, forming in particular, with the manifolds 5, a two-way circulation circuit (a cooled way passing through the manifolds 5 and a non-cooled way short-circuiting these manifolds), that can be selected with the by-pass component 14, is achieved advantageously by moulding.
This base body comprises substantially, as is shown in FIGS. 13 to 16, a conduit portion or end 13 for conveying exhaust gases, a contiguous conduit portion 13′ conveying said gases to the inlets 5′ of the manifolds 5 in a portion forming a cover 9′ and defining a volume 20, and, finally, a conduit portion 13″ conveying the cooled gases from the outlets 5″ of the manifolds 5 to the conduit portion 3″ through a passage controlled by the regulating component 16.
Of course, the invention is not limited to the embodiments described and illustrated in the accompanying drawings. Modifications are possible, particularly from the point of view of the composition of the various elements or by substitution of technical equivalents, without thereby departing from the protective scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
0405657 | May 2004 | FR | national |