WO2008152311A2

WO2008152311A2 - Device for insulating an exhaust manifold

Info

Publication number: WO2008152311A2
Application number: PCT/FR2008/050947
Authority: WO
Inventors: Murli Kadandale; Frédéric Greber
Original assignee: Faurecia Systemes D'echappement
Priority date: 2007-05-30
Filing date: 2008-05-29
Publication date: 2008-12-18
Also published as: EP2158383A2; FR2916801A1; WO2008152311A3; FR2916800A1; FR2916801B1

Abstract

The invention relates to an exhaust member (1) included in an exhaust line and connected to a thermal engine, that comprises an exhaust manifold (2) to be connected to the engine by at least one attachement means (3), and an insulation device (4) for said manifold (2) in the form of a housing (41) receiving inside thereof at least a portion of the manifold (2). The housing (41) includes: at least one opening (5) for the inlet into the device (4) of the exhaust gases from the engine; at least one opening (51) for the outlet of the exhaust gases out of the device (4); at least one opening (52) for the passage of attachment means (3) for attaching the exhaust member (1) on the engine. This member is characterised in that it comprises at least one strut extending at least inside the housing (41) and adapted for offsetting outside said housing (41) a manoeuvring member (30) comprised in said attachment means (3).

Description

DEVICE FOR INSULATING AN EXHAUST MANIFOLD

The present invention relates to an isolation device of an exhaust manifold and to an exhaust element comprising such an isolation device and such a collector.

This invention relates to the field of the automotive industry and, more particularly, that of the manufacture of equipment to ensure the escape of gases from the combustion of a fuel within an internal combustion engine.

Such equipment is in the form of an exhaust line connected to the engine and comprising a plurality of exhaust elements including an exhaust manifold through which this exhaust line is connected to the engine.

In fact, such an exhaust manifold usually comprises, on the one hand, an inlet flange intended to be fixed directly on the engine, more particularly on the cylinder head of this engine, on the other hand, an outlet flange.

(usually called a turbo flange) intended to be connected to another exhaust element of the exhaust line

(In particular to a turbocharger) and, secondly, a pipe, connecting the inlet and outlet flanges, and within which the exhaust gases from the engine flow.

This exhaust manifold is directly attached to the engine so that the exhaust gases entering the manifold have a particularly high temperature, corresponding substantially to that of the fuel combustion within the engine.

Such an exhaust manifold radiates, then, a strong heat inside the engine compartment which also receives a plurality of other parts likely to suffer damage or malfunction under the effect of such heat . Moreover, such a radiation generates a significant heat loss and results in a cooling of the exhaust gas within the exhaust line, which is detrimental to the depollution of these gases by a depollution element that includes this line of exhaust, downstream of this collector.

In order to remedy such a disadvantage, it is known to complete such a collector by a device capable of ensuring its insulation.

Such a device is in the form of two half-shells, positioned on either side of the manifold, extending over the pipe, this between the inlet flange and the outlet flange. These half-shells are made integral with the manifold by welding, especially at the junction between the pipe and a flange. In fact, such a half-shell is positioned at a distance from the collector so as to define, between this collector and such a half-shell, a spacing constituting an insulating air gap.

Such a design has, however, many disadvantages.

Thus and as evoked above, the manifold comprises an inlet flange directly fixed to the engine, this by means of a fastening means (stud, screw or the like) screwed into the engine and passing through an opening formed in said flange. Such a fixing means comprises an operating member (nut, screw head) that must be operated using a suitable tool. However, the presence of the isolation device greatly limits the accessibility of this tool to the operating member. In addition, because of the need for such accessibility, the spacing between a half-shell and the collector is greatly reduced so as to limit considerably the thickness of the insulating air gap which has the effect of reducing the quality of the insulation.

Another disadvantage is that the exhaust gas entering the manifold has a temperature greater than 350 ^° C. and that, for such temperatures, the heat transmission, in an airlayer insulating system, is mainly by radiation.

Such a type of heat transmission then results in a rapid rise in temperature of the insulation device which ensures, in fact, appropriate insulation only for a short time from the start of the cold engine.

This has the effect that the temperature of the insulation device quickly reaches that of the exhaust gas circulating in the collector which does not, in any way, to ensure the protection of the environment of the collector which is, in fact, provided effectively only when the temperature of the isolation device is less than 350 °.

Such a type of heat transfer also causes a significant loss of calories and, consequently, a decrease in the temperature of the exhaust gases at and downstream of the collector which is detrimental to the quality of the depollution of these gas by a depollution element located downstream of said collector. In fact, the air gap insulation essentially allows to maintain an appropriate gas temperature for an effective depollution, this for a short time from the start of the cold engine, so during the priming of the engine. element of depollution.

Another disadvantage comes from the temperature difference between the isolation device and the collector. This difference in temperature causes stresses due to differential expansion so that it is essential to provide sliding zones between the half-shell and the manifold piping to ensure the reliability of the system.

Yet another disadvantage is that the aforementioned insulation device has poor performance in sound insulation.

Finally and as evoked above, the collector is fixed directly on the cylinder head of the engine. In order to guarantee the seal between this manifold and this engine, it is usual to interpose therebetween a seal which, on the one hand, is constituted by an additional piece and on the other hand must be made of a material compatible with the nature and temperature of the exhaust gas.

The invention is intended to overcome the disadvantages of devices of the state of the art. For this purpose, the present invention relates to an exhaust element, on the one hand, that comprises an exhaust line of gases from the combustion of a fuel within a combustion engine of a motor vehicle, on the other hand, which is connected to this heat engine and, on the other hand, which has an exhaust manifold, intended to be secured to the engine by means of at least one fastening means comprising an element for its maneuver, and an isolation device of the exhaust manifold being in the form of a housing, receiving internally at least a portion of this collector, and comprising:

at least one opening for the entry into the device of the exhaust gases coming from the engine; at least one opening for the exhaust gas outlet out of the device; at least one opening for the passage of a means for fixing the exhaust element on the engine;

- characterized in that it comprises at least one spacer, extending at least inside the housing, and adapted to deport, outside of this housing, a maneuvering means that comprises the fixing means.

According to a first embodiment, the housing is constituted by a box having a bottom and a cover closing this box. The collector comprises at least one inlet flange positioned against the bottom of this box while the spacer extends between this inlet flange and the cover of this housing.

According to a second embodiment, the housing comprises two half-shells, assembled by means of assembly, and positioned on either side of at least a part of the collector, more particularly on either side of at least a pipe that includes this collector and which extends from an inlet flange that includes this collector.

In this case, the spacer extends from the manifold, more particularly from an inlet flange that includes this manifold, at least to near an opening for the passage of a fastening means of the exhaust element on the motor defined at the level of the wall of at least one half-shell of the housing.

An additional feature relates to the fact that the box, the lid or the half-shells are made from at least one sheet of metallic material, more particularly a sheet of aluminum and / or steel, in particular stainless steel, alumina steel, for example co-laminated, or other, this by deformation, in particular preceded by cutting.

Yet another feature relates to the fact that, on the one hand, the housing comprises at least one means for dressing, at least in part, a spacer and, on the other hand, it is defined between such a spacer and its connecting means. cladding, a gap which, as the case may be, defines an air gap or contains means for isolating this spacer.

Finally, the exhaust element comprises, between the exhaust manifold and the inner wall of the housing, a spacing which, as the case may be, defines an air space or contains means for isolating this manifold.

The invention also relates to an exhaust line of the gases resulting from the combustion of a fuel within a combustion engine of a motor vehicle and comprising at least one exhaust element having the above-mentioned characteristics.

Finally, the invention relates to a motor vehicle comprising a heat engine and an exhaust line of gases from the combustion of a fuel within said engine to which this exhaust line is connected. This vehicle is characterized by the fact that its exhaust line has at least one exhaust element having the above-mentioned characteristics.

The advantages of the present invention consist in that the isolation device is in the form of a housing intended to internally receive the collector, which advantageously makes it possible to provide appropriate insulation for this collector.

This housing has at least one opening for the passage of a fixing means of the housing on the engine which advantageously makes it possible to overcome the problems of accessibility to such a fastening means since such a means of fixing through the housing and can be operated from outside this housing.

Advantageously, the housing of this isolation device is designed to receive, internally, an existing collector, requiring no modification. In fact and advantageously, this collector is simply positioned inside said housing before ensuring the attachment of 1 'collector + housing assembly on the engine. An additional advantage is that the isolation device does not require welding of an isolation device on the collector as for devices of the state of the art.

Finally, the assembly of the collector and its isolation device is done concomitantly and during a single mounting operation.

Other objects and advantages of the present invention will become apparent from the following description relating to embodiments which are given by way of indicative and non-limiting examples.

The understanding of this description will be facilitated by reference to the appended drawings in which:

FIG. 1 is a schematic front view in partial section corresponding to a first embodiment of an exhaust element according to the invention and consisting of a insulation device internally receiving an exhaust manifold;

- Figure 2 is a schematic side view and in partial section of the exhaust element illustrated in Figure 1; - Figure 3 is a schematic partial view in perspective, exploded and in section of the isolation device illustrated in Figures 1 and 2;

FIG. 4 is a schematic partial view in section corresponding to a detail of an insulating and / or sealing joint that the insulation device illustrated in FIG. 3 has at an inlet opening. exit of gases;

FIG. 5 is a schematic and bottom view of a particular embodiment of the bottom of an isolation device; - Figures 6 and 6a are schematic views corresponding to a detail of a spacer and a fixing means of the exhaust element on the engine;

- Figure 7 is a schematic front view and exploded corresponding to a second embodiment of an exhaust element according to the invention;

- Figure 8 is a schematic side view of the exhaust element illustrated in Figure 7.

The present invention relates to the field of the automotive industry and, more particularly, that of the manufacture of equipment to ensure the escape of gases from the combustion of a fuel within an internal combustion engine.

Such equipment is in the form of an exhaust line connected to the engine and having a plurality of exhaust elements.

In particular, such an exhaust line comprises an exhaust element 1, through which 1 this exhaust line is connected to the engine. This exhaust element

1 comprises (or is at least partly constituted by) an exhaust manifold 2. In this regard, it will be observed that such an exhaust manifold 2 comprises, usually, on the one hand, at least one inlet flange 21 intended to be fixed directly on the engine (more particularly on the cylinder head of this engine) and comprising: at least one inlet orifice 210, inside the manifold 2, gases coming from the engine, such an inlet orifice 210 coming to be positioned in line with a gas escape orifice that includes the cylinder head of this engine; - At least one opening 211 for the passage of a fixing means 3 of the collector 2 on the engine.

On the other hand, this manifold 2 comprises a pipe 23 inside which flows the exhaust gases from the engine. This pipe 23 extends from said inlet flange 21, to which this pipe 23 is connected, in particular by welding.

This manifold 2 is intended to be connected to another exhaust element (in particular a turbocharger) that comprises the exhaust line and which is situated downstream of this manifold 2.

According to a first embodiment not shown, the pipe 23 of this manifold 2 is directly connected to such another exhaust element, in particular by welding.

However, according to an embodiment illustrated in FIGS. 1, 2, 7 and 8, the collector 2 further comprises an outlet flange 22 (respectively called a turbo flange), on the one hand, connected (usually by welding) to the piping 23 and, secondly, intended to be connected to such another exhaust element of the exhaust line (respectively to a turbocharger), located downstream of this collector 2.

In such a case, said pipe 23 connects the inlet flanges 21 and outlet 22, and extends between these flanges (21, 22).

This output flange 22 then comprises at least one orifice 220 for the exit of the exhaust gases from this manifold 2. This outlet flange 22 may, again, comprise at least one opening 221 (or an orifice) for the passage (or reception) of a means for fixing this manifold 2 to an exhaust element that comprises the exhaust line downstream of this manifold 2 (element d downstream exhaust). The invention relates, in fact, to a device 4 designed to ensure the isolation of such an exhaust manifold 2.

Such an isolation device 4 is in the form of a housing 41 intended to internally receive at least a portion of the collector 2. This housing 41 comprises, on the one hand, at least one opening

5 for the entry into the device 4, the exhaust gas from the engine.

Such an inlet opening 5 may, according to a particular embodiment, be intended to be positioned at the right of a gas exhaust port that includes the cylinder head of the engine and to the right of an orifice 210 d gas inlet in the manifold 2 (Figures 1 and 2).

On the other hand, this case 41 has at least one opening

51 for the exhaust gas outlet out of the isolation device 4.

Such an outlet opening 51 may, according to a particular embodiment, be intended to be positioned at right or near a port 220 of the gas outlet that comprises the collector 2 (Figures 1 and 2), or even the right a gas inlet port in another downstream exhaust element.

This housing 41 further includes at least one opening 52 for the passage of a fixing means 3 of this housing 41 on the motor. FIGS. 1 to 5 show a first embodiment of a housing 41 constituting at least part of such an insulation device 4.

As visible in these same figures, this housing 41 is constituted, on the one hand, by a box 42 having a bottom 420 at which are defined or the openings 5 of gas inlet and at least one opening 52 for the passage of a 3. Actually, the bottom 420 of this box 42 may be intended to come into contact with the engine.

On the other hand, this housing 41 is constituted by a cover 43 at which are defined or the outlet openings 51 of the gas and at least one other opening 52 for the passage of a fixing means 3.

The box 42 and the lid 43 each have a flange at which the assembly (particularly by welding) of this box 42 and of the lid 43 is made to close the case 41, after having positioned therein, internally, the collector 2.

The box 42 and / or the lid 43 are made, at least in part, of a metallic material, more particularly aluminum and / or steel, in particular stainless steel, alumina steel, for example co-laminated, or other.

In fact, the box 42 and / or the lid 43 are made from a sheet of a metallic material, more particularly aluminum and / or steel, in particular stainless steel, alumina steel, for example co-laminated, or else, this by deformation (in particular by stamping or pressing) in particular preceded by cutting.

The bottom 420 of the box 42 of the housing 41 is constituted, at least at the inlet opening or openings 5 of the gases

(Even and preferably on the entirety of this bottom 420 as illustrated in Figures 1 to 3), by a seal 6 of insulation and / or sealing.

Additionally, the cover 43 of the box 42 of the housing 41 may be formed, at least at the outlet or openings 51 of the gas, by a seal 61 of insulation and / or sealing.

The seal (6; 61) of insulation and / or sealing is at least partly constituted by at least one plate, more particularly at least one sheet, made of aluminum and / or steel, in particular stainless steel , of alumina steel, for example co-laminated, or other, and provided with at least one opening inlet 5 or outlet 51 gas, or at least one opening 52 for passage of a fastening means 3.

A particular embodiment consists in that the seal (6; 61) of insulation and / or sealing consists, on the one hand, by two plates (62, 63), more particularly two sheets, made of aluminum and / or steel, especially stainless steel, alumina steel, for example co-laminated, or other and, secondly, a layer of an insulating material 64, in particular compressible and / or compressed (paper, fiber compressed), disposed between these two plates (62, 63) of steel, and provided, like the latter (62, 63), at least one inlet opening 5 or outlet 51 of the gas, or even to at least one opening 52 for passing a fastening means 3.

In this connection, it should be noted that the exhaust gases are liable to cause damage to the insulating material which constitutes the insulating layer 64, more particularly to the insulating material bordering the inlet or outlet opening 51 or these gases.

In order to avoid such degradations, the seal (6; 61) for insulating and / or sealing comprises, additionally and as can be seen in FIG. 4, a fire barrier means 65 (more particularly constituted by a protective ring -feu) positioned at such an inlet opening 5 or outlet 51 gas, including internally bordering such an opening (5, 51).

In fact, such a fire-resistant means 65 dress at least the edge of the layer 64 of insulating material (or even - and preferably - the edge of the two steel plates 62, 63), this at such an opening input 5 or output 51 of the gases. As can be seen in FIG. 4, the fire barrier means 65 have a peripheral groove inside which the edges of the two steel plates (62; 63) delimiting an inlet or outlet opening 51 are engaged. This fire-resistant means 65 is preferably secured to said plates (62; 63), in particular by crimping, welding or the like. As mentioned above, the bottom 420 of the box 42 of the casing 41 is constituted, at least at the level of the inlet opening (s) 5 of the gases, by a seal 6 of insulation and / or sealing . Such an insulating and / or sealing gasket 6 is then, and preferably, located at the bottom 420 of the box 42 of the housing 41. In fact, this bottom 420 may, more particularly, be (at least part) constituted by such a seal 6.

FIGS. 1 to 4 show an embodiment in which the bottom 420 of the box 42 of the housing 41 is integrally constituted by such an insulating and / or sealing gasket 6.

In fact, this seal 6 may consist of a single plate as mentioned above (not shown) but is, preferably and as visible in these figures, constituted, on the one hand, by two plates (62; type above and, secondly, by a layer of an insulating material 64 of the aforementioned type and interposed between these two plates (62, 63), in particular supplemented by a firewall means 65. However and according to another mode of realization (Figure 5), the bottom 420 of the box 42 of the housing 41 is constituted, on the one hand, by a panel 66 provided with at least one cutout 67, at which 67 is positioned an inlet flange 21 that comprises the collector 2, and preferably having the shape (especially adjusted) of such an inlet flange 21.

It will be observed that such a panel 66 may be constituted by at least one plate (in particular of aluminum and / or steel - for example of the aforementioned type), more particularly so as to define an element of insulation and / or sealing like the seal (6; 61) described above.

On the other hand, the bottom 420 of the box 42 of this housing 41 is constituted by at least one seal 6 which is positioned inside a cutout 67 of the panel 66.

Such a gasket 6 has a shape, preferably adjusted to that of such a cutout 67, or even (and preferably) adjusted to that of the inlet flange 21. In addition, this seal 6 has at least one inlet opening 5 of the gases (or preferably - at least one opening 52 for passage of a fastening means 3) which, within the exhaust element 1, is positioned at a port 210 for entering the gas (respectively an opening 211 for passage of a fixing means 3) that has the inlet flange 21 of the collector 2.

In addition, such a seal 6 is, at least in part, constituted by at least one plate, more particularly at least one plate, made of aluminum and / or steel, in particular stainless steel, of alumina steel, for example co- laminated, this like a seal 6 insulation and / or sealing described above.

An additional feature is that the box 42 of the housing 41 and / or the seal 6 of insulation and / or sealing comprises means 68 for securing such a seal 6 insulation and / or sealing at remaining from the box

42.

Such securing means 68 may be constituted by a clip, a tongue (able to be deformed to be folded down), a weld or any other assembly system.

In fact, these securing means 68 are preferably defined at the joint 6 and are designed to cooperate with the remainder of the box 42 of the housing 41 (Figure 5).

The presence of these securing means 68 advantageously allows only the replacement of the seal

6 (which is not reusable because it loses its elasticity after a first assembly) without imposing the replacement of the isolation device 4 and / or the collector 2.

According to a first exemplary embodiment (not shown), the panel 66 comprises a single cutout 67 at which the inlet flange 21 of the collector 2 is positioned on the one hand and the gasket on the other hand 6 insulation and / or sealing. However, according to another embodiment illustrated in FIG. 5, the panel 66 comprises a plurality of cutouts 67.

At each of these cutouts 67 is positioned, on the one hand, an inlet flange 21 (at which 21 is defined a single orifice 210 of gas inlet) that includes the collector 2 and, d ' on the other hand and as the case may be, an individual insulating and / or sealing gasket 6 or a portion 69 of such a gasket 6 (FIG. 5).

In the case of a seal 6 having a plurality of portions 69, these portions 69 are preferably connected in pairs by means of a tongue.

Such a tongue may be secured to a panel portion 66 extending between two cuts 67, more particularly by securing means 68 of the aforementioned type.

As evoked above, the isolation device 4 is in the form of a housing 41 intended to internally receive at least a portion of the collector 2.

FIGS. 7 and 8 illustrate a second embodiment of such a housing 41 comprising at least two half-shells (44, 44 ') positioned on either side of at least a portion of the collector 2.

These two half-shells (44, 44 ') are assembled by means of assembly (constituted, as appropriate, by welding, crimping, soldering, riveting or the like) and preferably have a shape substantially symmetrical with respect to an assembly plane of these two half-shells (44, 44 ').

Each of these two half-shells (44, 44 ') has, on the one hand, at least a portion (50, 50') of at least one opening 5 for the entry of the exhaust gases into the housing

41 and, on the other hand, at least a portion (510, 510 ') of at least one opening 51 for the exhaust gas outlet of this housing 41. Thus, the opening or openings 5 for the entry of the gas and the opening or openings 51 for the gas outlet are at least partially defined at each half-shell (44,

44 ') of the case 41. On the other hand, each of these two half-shells (44, 44 ') has at least one opening 52 for the passage of a fixing means 3.

In this regard, it should be noted that such an opening 52 is defined by at least one cutoff 520 (in particular a notch or cut) made at the wall of the half-shell (44, 44 ').

Such a cutoff 520 is preferably completed by at least one deformation (521, 521 ') of this wall made on at least one side, or (and preferably) on both sides, of this cutoff 520.

Thus, and according to a preferred embodiment illustrated in FIGS. 7 and 8, such an opening 52 is defined, on the one hand, by at least one cutoff 520 made at the level of the wall of the half-shell (44, 44 ') and on the other hand, by a first convex deformation 521 of this wall made on one side of this cut-off 520 as well as by a concave deformation 521 'of this wall made on the other side of this cut-off 520.

According to an additional characteristic, these two half-shells (44, 44 ') are made, at least in part, of a metallic material, more particularly of aluminum and / or of steel, in particular of stainless steel, of alumina steel, for example co-laminated, or other.

In fact, these two half-shells (44, 44 ') are preferably made from a sheet of a metallic material, more particularly aluminum and / or steel, in particular stainless steel, alumina steel, for example co-laminated, or other, this by deformation (in particular by stamping or pressing) in particular preceded by cutting. The invention also relates to an exhaust element 1, on the one hand, that comprises an exhaust line of the gases resulting from the combustion of a fuel within a heat engine of a motor vehicle, d on the other hand, which is connected to this heat engine and, secondly, which comprises (or which is at least partially defined by) an exhaust manifold 2, in particular of traditional design. According to the invention, this exhaust element 1 comprises, again, an isolation device 4 of such an exhaust manifold 2 which is disposed, at least in part, inside this isolation device 4 , this isolation device 4 having the above characteristics.

In this connection, it will be recalled that the exhaust manifold 2 comprises at least one gas inlet orifice 210, at least one gas outlet orifice 220 and at least one opening (211; 221) for the passage of a 3. There has been illustrated in FIGS. 1 and 2 such an exhaust manifold 2 disposed integrally inside an isolation device 4 according to the first embodiment described above.

In such a case, the inlet opening 210 of the gas manifold 2 is positioned opposite a gas inlet opening 5 which comprises the housing 41 (bottom 420 of the box 42) of the isolation device 4 .

A port 220 of the gas outlet of the manifold 2 is positioned facing an opening 51 of the gas outlet that comprises the housing 41 (cover 43) of the isolation device 4.

While an opening (211; 221) for passage of a fixing means 3 of the collector 2 is positioned opposite an opening 52 for the passage of a fastening means 3 that includes the casing 41 (box 42 and cover 43) of the isolation device

4.

The exhaust manifold 2 has an inlet flange

21 positioned in the bottom 420 of the housing 41 (box 42) of the isolation device 4, more particularly over a seal 6 of insulation and / or sealing that includes this case

41 (which defines the bottom 420 of this case 41).

The exhaust manifold 2 further comprises an outlet flange 22. The housing 41 of the insulation device 4 has a gas outlet opening 51 bordered by a flange which (according to a particular embodiment of the invention) constitutes a seal 61 of insulation and / or sealing and which is positioned over said outlet flange 22 of the collector 2 (Figures 1 and 2).

FIGS. 7 and 8 illustrate an exhaust manifold 2 only part of which (in this case the pipework 23) is disposed inside an isolation device 4 according to the second embodiment described above. above .

As can be seen in FIG. 8, the gas inlet opening 5 in the isolation device 4 is positioned at the rear of the inlet flange 21 (the front of this flange 21 being intended to be fixed directly on the engine, especially after interposition of a seal).

The opening 51 of the gas outlet of the isolation device

4 may be positioned, or near the outlet of the pipe 23 when it is directly connected to another downstream exhaust element (not shown solution), or (as illustrated in FIGS. 7 and 8) at the rear of the outlet flange 22 (the front of this flange 22 being intended to be fixed directly to a downstream exhaust element, especially after interposition of a seal).

This inlet flange 21 has an opening 211 for the passage of a fixing means 3 of the collector 2, this opening 211 being positioned facing (but at a determined distance as will be described below) an opening 52 passage of a fastening means 3 that includes the housing 41 (half-shells 44, 44 ') of the isolation device 4.

As can be seen in FIG. 8, this insulating device 4 then incorporates part of the exhaust manifold 2 (more particularly the pipe 23 of this manifold 2) and at least partly covers the rear of the inlet flange. 21 or the output flange 22.

According to another characteristic, the exhaust element 1 according to the invention comprises, between the exhaust manifold 2 and the inner wall of the housing 41, a spacing 7 which, as the case may be, defines an air knife or contains a way

71 to isolate this collector 2. A preferred embodiment consists in that this means 71 of insulation comprises at least one layer of an insulating material constituted by a layer of fibers and / or by an insulation gel. In fact, such an isolation means 71 is preferably in the form of two insulating half-blocks (72, 72 ') positioned on either side of at least a portion of the collector 2, more particularly on either side of the pipe 23 of this manifold 2. According to a particular embodiment, these two half-blocks (72, 72 ') can be assembled around the manifold 2 before introduction of the collector assembly 2 + half -blocks (72, 72 ') inside the box 42 of the housing 41 corresponding to the device 4 insulation according to the first embodiment described above.

Another embodiment consists in that each insulating half-block (72, 72 ') is positioned inside a half-shell (44, 44') that comprises the housing (41) of the device (4) insulation according to the second embodiment of this housing 41, this before assembly of these two half-shells (44, 44 ').

In this respect, it will be observed that these insulating half-blocks (72,

72 ') are preferably secured to the half-shells

(44, 44 ') by gravity, mechanical holding means (clip, pin or the like) or by chemical means

(glue).

An additional feature is that each insulating half-block (72, 72 ') has a complementary shape, preferably adjusted to that of a half-shell (44, 44') within which such a half -block (72, 72 ') is positioned and / or a shape complementary to that of the collector

2, more particularly of the pipe 23 of this collector 2.

An additional feature of the present invention is that the exhaust element 1 comprises at least one means 8, extending at least inside the housing 41, and designed to deport, outside this housing 41, a maneuvering member 30 that includes the fastening means 3.

According to a first embodiment, the invention consists in using a fastening means 3 in the form of a stepped screw, in particular completed by a washer, this stepped screw passing through the housing 41 (extending through at least an opening 52 mentioned above) and an opening 211 that comprises the inlet flange 21 of the collector 2. The shoulder of this screw and / or this washer bear on this inlet flange 21 of the collector 2, which allows to deport the operating member (head of the shouldered screw) outside the housing 41.

Another embodiment consists in that the fixing means 3 adopts the shape of a screw, comprising an actuating member 30 constituted by the head of this screw. However, according to a preferred embodiment of the invention, such a fastening means 3 is in the form of a stud 31 completed by an actuating member 30 constituted by a nut.

Whatever this fixing means 3 (screw, shouldered screw, stud), the latter, on the one hand, is secured to the motor, on the other hand, through an opening 211 of the manifold 2 (more particularly an opening 211 that comprises the inlet flange 22 of this manifold 2) and, on the other hand, passes through the housing 41 while extending through at least one opening 52 of the housing 41, so that, d on the one hand, its thread intended to cooperate with the motor and, on the other hand, its operating member 30 are, at least in part, positioned outside this housing 41.

In the case of a fastening means 3 consisting of a screw or a stud 31, the means 8 for moving the operating member 30 of such a fastening means 3 outside the housing 41 is, in fact, constituted by a spacer 8.

This spacer 8 is constituted by an element 81 having a through and axial bore for receiving, internally and in a through manner, a part of the fixing 3, more particularly a portion of the threaded portion of the rod of this fixing means 3.

A preferred embodiment is that this pierced element 81 takes the form of a tube (especially in the form of a column), a hollow cylinder or the like.

As mentioned above, the exhaust manifold 2 comprises an inlet flange 21 intended to be fixed to the engine via at least one fastening means 3.

In fact, the spacer 8, on the one hand, extends from such an inlet flange 21 and, on the other hand, is associated with such an inlet flange 21, more particularly by screwing or and preferably by welding.

As mentioned above, the inlet flange 21 of the manifold 2 is provided with at least one opening 211 for the passage of a means 3 for attachment to the engine. It is, more particularly, with regard to such an opening 211, preferably in the extension thereof 211, that is located the piercing of the spacer 8 which can, then, lead at least in view of a In this regard, it will be observed that the section of the bore is greater or, and preferably, equal to that of the opening 211 that comprises the inlet flange 21.

FIGS. 1 to 6 show a first embodiment of a box 41 constituted by a box 42 comprising a bottom 420 as well as by a cover 43 enclosing this box 42. In this case, the collector 2 comprises at least one inlet flange 21 positioned against the bottom 420 of this box 42.

As seen in Figures 1, 2, 6 and 6a, the spacer 8 extends, in fact, between the inlet flange 21 of the collector 2 and the cover 43 of this housing 41.

This spacer 8 is thus interposed between the inlet flange 21 of the exhaust manifold 2 and the cover 43 of the housing 41 and has an axial bore opening, also, at an opening 52 for passing a means 3 which the cover 43 of the isolation device 4 comprises. According to a first embodiment illustrated in FIG. 6, such an opening (52) for the passage of a fastening means (3) can be positioned facing such a spacer 8, more particularly a hole that this spacer presents. 8. In this regard, it will be observed that the drilling of this spacer 8 and the opening 52 for the passage of a fixing means 3 defined at the cover 43 have, in fact, a similar shape and / or dimension, preferably adjusted. In such a case, the cover 43 of the housing 41 is, then, wedged between the spacer 8 and an operating member 30 (screw head or nut) that comprises the fixing means 3.

Another embodiment illustrated in FIG. 6a consists in that the lid 43 has a flange which comes to die on the cylindrical portion of this spacer 8.

FIGS. 7 and 8 show a second embodiment of an escapement element 1 comprising an isolation device 4 constituted by a housing 41 comprising two half-shells (44, 44 '), the wall of which at least one (44, 44 ') is provided with an opening 52 for the passage of a fastening means 3 of the exhaust element 1 on the engine.

In such a case, the spacer 8 extends from the manifold 2, more particularly from an inlet flange 21 that includes this manifold 2, at least to near such an opening 52 for the passage of a fastening means 3.

This spacer 8 can then extend in part outside the housing 41 or, and preferably, be positioned inside this housing 41, in particular by being set back with respect to the opening 52 or at the level of this one 52.

Another characteristic consists in that the housing 41 of the isolation device 4 comprises at least one means 9 for covering, at least in part, a spacer 8.

In fact, such a dressing means 9 consists of a deformation 521 of the wall of this housing 41. As can be seen in FIGS. 7 and 8, such a covering means 9 may consist of a deformation of the wall of a half-shell (44, 44 '), more particularly of a convex deformation 521 defining, in part, the opening 52 for the passage of a fastening means 3.

An additional feature is that the spacer 8 and its cladding means 9 have similar shapes and / or dimensions, preferably adjusted.

In fact, there is defined, between such a spacer 8 and its cladding means 9, a spacing which, as the case may be, defines an air space or contains means for isolating this spacer 8.

Such an embodiment advantageously makes it possible to define an insulating layer between these means (8, 9) and thus to reduce the heat radiated by the housing 41 at the level of the spacer 8.

In this regard, it will be observed that when such spacing contains an insulation means, it may comprise at least one layer of an insulating material consisting of a fiber web and / or an insulation gel.

Finally, the isolation device 4 (more particularly the housing 41 and / or the insulating means 71) is shaped to receive the spacer 8 adapted to deport the operating member 30 of the fixing means 3. A In this respect and as can be seen in FIG. 7, an insulating half-block (72, 72 ') of such an insulating means 71 may then have a cutout, an opening, a clearance or a cradle of a shape adapted to that spacer 8.

The invention also relates to a gas exhaust line comprising at least one exhaust element 1 having the above-mentioned characteristics.

Finally, the invention relates to a motor vehicle comprising a heat engine and an exhaust line of gases from the combustion of a fuel within said engine to which this exhaust line is connected. This motor vehicle is characterized in that its exhaust line comprises at least one exhaust element 1 having the above characteristics.

In this regard, it will be observed that this vehicle also comprises at least one fastening means 3 of the exhaust element 1 on the engine, such fastening means 3 being preferably constituted by a pin 31 made integral. of the engine and completed, especially after implementation of the exhaust element 1 according to the invention, by an actuating member 30 constituted by a nut.

Claims

1. Exhaust element (1), on the one hand, that comprises an exhaust line of the gases resulting from the combustion of a fuel within a combustion engine of a motor vehicle, on the other hand, which is connected to this heat engine and, secondly, which comprises an exhaust manifold (2), intended to be secured to the engine by means of at least one fastening means (3) comprising an element for its maneuvering (30), as well as an isolation device (4) for this exhaust manifold (2) in the form of a housing (41), receiving internally at least part of this manifold ( 2), and comprising: at least one opening (5) for the entry into the device (4) of exhaust gases from the engine;

at least one opening (51) for the exit of the exhaust gases from the device (4);

- at least one opening (52) for the passage of a fastening means (3) of the exhaust element (1) on the engine;

- characterized in that it comprises at least one spacer (8), extending at least inside the housing (41), and adapted to deport, outside this housing (41), a maneuvering member (30) that comprises the fixing means (3).

2. Exhaust element (1) according to claim 1, characterized in that the spacer (8) is constituted by a member (81) having a through bore and axial to receive, internally and in a through manner, a part of the fastening means (3).

3. Exhaust element (1) according to claim 2, characterized in that the pierced element (81) takes the form of a tube, a hollow cylinder or the like.

4. Exhaust element (1) according to any one of the preceding claims, characterized in that the manifold (2) comprises at least one inlet flange (21), on the one hand, intended to be fixed to the motor via at least one fastening means (3) and, secondly, to which (21) is associated and from which (21) extends the spacer (8).

5. Exhaust element (1) according to claims 2 and 4, characterized in that the inlet flange (21) of the collector (2) is provided with at least one opening (211) for the passage of means (3) for fixing it to the engine and to which (211), preferably in the extension of which, is located the drilling of the spacer (8).

6. Exhaust element (1) according to any one of claims 1 to 5, characterized in that, firstly, the housing (41) is constituted by a box (42) having a bottom (420). as well as by a cover (43) closing this box (42) and that, on the other hand, the collector (2) comprises at least one input flange (21) positioned against the bottom (420) of this box (42). ) while the spacer (8) extends between this inlet flange (21) and the cover (43) of this housing (41).

7. Exhaust element (1) according to claim 6, characterized in that the opening (s) (5) of the gas inlet, respectively at least one opening (52) for the passage of a fixing means ( 3) are, on the one hand, defined at the bottom (420) of the box (42) of the housing (41) and, on the other hand, positioned opposite a gas inlet port (210) respectively an opening (211) for the passage of a fastening means (3), that includes the inlet flange (21) of the manifold (2) while the or the openings (51) of the gas outlet , respectively at least one other opening (52) for the passage of a fixing means (3) are, firstly, defined at the cover (43) of the housing (41) and, secondly, positioned facing a gas outlet opening (220) that includes the collector (2), respectively a spacer (8), more particularly a bore that has such a spacer (8).

8. Exhaust element (1) according to any one of claims 6 or 7, characterized in that the bottom (420) and / or the cover (43) of the box (42) of the housing (41) is constituted, at least at the opening or openings (5) or outlet (51) of the gas, by a seal (6; 61) of insulation and / or sealing.

9. Exhaust element (1) according to claim 8, characterized in that the seal (6; 61) of insulation and / or sealing is at least partly constituted by at least one plate provided with at least one inlet opening (5) or outlet (51) of the gases.

10. Exhaust element (1) according to any one of claims 6 to 9, characterized in that the bottom (420) of the box (42) of the housing (41) is either integrally constituted by a seal ( 6) of insulation and / or sealing, is constituted, on the one hand, by a panel (66) provided with at least one cutout (67) at which is positioned an inlet flange (21) that comprises the collector (2) and, on the other hand, by at least one seal (6) coming to be positioned inside a cutout (67) of the panel (66) and having at least one opening inlet (5) of gases, or even at least one opening (52) for passage of a fixing means (3).

11. Exhaust element (1) according to any one of claims 1 to 5, characterized in that the housing (41) comprises two half-shells (44, 44 '), assembled by means of assembly, and positioned on either side of at least a portion of the collector (2), more particularly on either side of at least one pipe (23) that this collector (2) comprises and which extends to from an inlet flange (21) that includes this collector (2).

Exhaust element (1) according to claim 11, characterized in that the spacer (8) extends from the manifold (2), more particularly from an inlet flange (21). included in this manifold (2), at least until close to an opening (52) for the passage of a fastening means (3) of the exhaust element (1) on the engine defined at the level of the wall of at least one half-shell (44, 44 ') of the housing (2).

13. Exhaust element (1) according to claim 12, characterized in that the opening (52) for the passage of a fixing means (3) is defined by at least one cut (520) made at the level of the wall of the half-shell (44, 44 '), preferably completed by at least one deformation (521, 521') of this wall made on at least one side or, preferably, on both sides, of this cutoff (520).

14. Exhaust element (1) according to any one of claims 11 to 13, characterized in that the opening (s) (5) for the gas inlet and the opening (s) (51) for the outlet gases are at least partially defined at each half-shell (44, 44 ') of the housing (41).

15. Exhaust element (1) according to any one of claims 6 to 14, characterized in that, depending on the case, the box (42), the lid (43) or the half-shell (44) , 44 ') are made from at least one sheet of metallic material, more particularly a sheet of aluminum and / or steel, in particular of stainless steel, of alumina steel, for example co-laminated, or else, this by deformation, in particular preceded by a cutting.

16. Exhaust element (1) according to any one of the preceding claims, characterized in that, on the one hand, the housing (41) comprises at least one means (9) for dressing, at least in part, a spacer (8) and, on the other hand, is defined, between such a spacer (8) and its covering means (9), a spacing which, as the case may be, defines an air gap or contains a means for isolating this spacer (8).

17. Exhaust element (1) according to any one of the preceding claims, characterized in that it comprises, between the exhaust manifold (2) and the inner wall of the housing (41), a spacing (7). ) who, as the case may be, defines an air gap or contains means (71) for isolating this collector (2).

18. Exhaust element (1) according to any one of claims 16 or 17, characterized in that the means (71) for isolating, as the case, the spacer (8) or the collector (2) comprises at least one layer of an insulating material consisting of a layer of fibers and / or an insulation gel.

19. Exhaust element (1) according to claim 17, characterized in that the means (71) for isolating the collector is constituted by two insulating half-blocks (72, 72 ') positioned on either side of at least a part of the collector (2).