WO2005075862A1 - Device for sealing an exhaust line pipe - Google Patents

Abstract

The invention relates to a device (3) for sealing the end (4) of a pipe (1) which belongs to the exhaust line of an internal combustion engine and which defines an exhaust gas passage. The inventive device (3) comprises: (i) a check valve (5) which is associated with pivot mounting means (6) which enable said valve (5) to pivot between a closed pipe (1) position and at least one open pipe position; and (ii) means (11) for returning the valve (5) to the closed pipe (1) position. The invention is characterised in that it comprises means (13) which, at least in the open pipe (1) position, are arranged to divert the exhaust gas flow from the pipe (1) in relation to the return means (11), such as to prevent the gas from reaching said return means (11).

Description

DEVICE FOR SEALING A CONDUIT OF AN EXHAUST LINE.

The present invention relates to a device for shutting off the end of a duct which comprises an exhaust line of an internal combustion engine.

This invention relates to the field of the automobile industry and, more particularly, that of equipment making it possible to ensure the escape of gases resulting from the combustion of a fuel within an internal combustion engine.

It will be observed that such equipment complements this heat engine and is constituted by an exhaust line, equipping the outlet of this engine, and usually comprising a silencer designed capable of reducing the noise emissions of this engine and of this line. exhaust.

In this regard, it was found that the acoustic efficiency of such a silencer increases with the resistance it was able to oppose to the passage of gases. Note, however, that too much resistance leads to an increase in pressure or back pressure inside the exhaust line, which results in a degradation of engine performance.

To take account of this phenomenon, it has already been proposed to use silencers operating in a dual mode. To adopt such an operation, these silencers comprise a closure device, mounted on a duct delimiting a passage for the exhaust gases, and usually comprising a valve mounted in an articulated manner with respect to said duct. This valve is arranged, on the one hand, so as to adopt, at low engine speed and in conditions of low pressure, a first position in which this valve ensures at least partially the sealing of said conduit in order to prevent the passage of these gases. On the other hand, this valve is arranged for, at high engine speed and when the back pressure increases in the line, gain another position (called open position) in which this valve allows the passage of gases through this conduit. The valve returns to the closed position when the back pressure decreases.

Thus, during its operation, the valve moves from a closed position (low speed) in lacquer-Lie, the back pressure is generated to optimize the acoustic efficiency of the silencer, to an open position (higher speed ) until reaching maximum travel. In this position, the generation of too high back pressure is avoided so as not to deteriorate the engine performance.

In order to allow such a valve to adopt such movements, the shutter device comprises means for returning this valve to the position for closing the duct, such return means usually being constituted by a return spring. .

In this regard, it will be observed that the pressure of the exhaust gas in the duct can be high so that the return spring, in order to resist such "pressure, must be able to be placed against the valve with a high preload. This results in the fact that, on the one hand, this spring comprises a large number of turns (the number of turns increasing with the value of the desired preload) and, on the other hand, the positioning of this spring is particularly complex in view of the requirements for installing the shutter device at the exhaust line (lack of space and bulk).

In addition, such a spring is placed in a particular environment (hot exhaust gases) whose temperature conditions considerably influence the characteristics (in particular of the restoring force or the preload) of said spring. so it is essential to use a specific material for the manufacture of this spring.

The need to use a specific material, which is more in large quantity (depending on the number of turns required), considerably increases the cost price of the spring which can represent up to half the cost price of the entire device shutter.

In addition, this spring being placed in an environmental barrier, it is repeatedly subjected to gases brought to very high temperature (up to 650 ° C) causing accelerated aging and premature wear of this spring.

The present invention aims to overcome the drawbacks of the devices of the prior art.

To this end, the invention relates to a device for shutting off the end of a conduit which comprises an exhaust line of an internal combustion engine and which delimits a passage for the exhaust gases, this device comprising, on the one hand, a valve associated with pivoting mounting means allowing this valve to pivot between a closed position and at least one position for opening the duct and, on the other hand, means for returning said valve to the position obturation of this conduit. This device is characterized in that it comprises means arranged to, at least in the open position of the duct, deflect the flow of the exhaust gases coming from this duct, this with respect to the return means and so as to prevent gases from reaching them.

According to another characteristic of the invention, the means for deflecting the flow of gases consist of a deflector interposed between the return means of the valve and the conduit, in particular the through end of the latter. According to an additional characteristic, the deflector is arranged on the path adopted by the exhaust gases at the outlet of this duct.

A first solution consists in that the deflector is defined by an additional element associated with the duct, with the valve, with the mounting means associated with the latter, with the return means of the latter, or even with a part of the silencer that the exhaust line.

In fact, this deflector can be associated with the means for mounting the valve or with the return means of the latter and is constituted by means capable of ensuring a rollover of at least part of these return means of the valve.

A second solution consists in that these means for deflecting the flow of gases consist of a deflector defined at the level of said valve or means for pivotally mounting the latter.

According to another characteristic of the invention, such a deflector is produced by deformation of said valve or of the mounting means, in particular by stamping.

According to an additional characteristic, this valve comprises a portion arranged to ensure the obturation of the conduit while the deflector is located in the extension of this obturation portion.

In fact, the portion of the valve intended for closing the duct extends substantially in a plane while the deflector deviates from this plane and either forms an angle with this plane or has a curvature at which this plane is positioned tangentially. The present invention also relates to a silencer that includes a gas exhaust line associated with an internal combustion engine and which includes a conduit defining an exhaust gas passage. This silencer is characterized by the fact that it comprises, at the level of said duct, a device for closing off this duct of the aforementioned type.

The invention also relates to a gas exhaust line associated with an internal combustion engine and comprising, in particular at the level of a silencer that such an exhaust line comprises, a duct delimiting a passage for gases. This exhaust line is characterized by the fact that it compoarte, at the level of said conduit, a device for closing off this conduit of the aforementioned type.

The advantages of the present invention consist in that the flow of the exhaust gases is deflected with respect to the return means of the valve. Consequently, these return means are no longer located in the flow of these gases or even in the immediate vicinity of this flow so that they no longer undergo, or at least to a much lesser extent, the repeated attacks of hot gases.

This results in an extension of the longevity of these return means for the production of which it can, moreover, be envisaged to use a less specific material (therefore more traditional and less expensive) than that of the return means of the state of the art.

The present invention will be better understood on reading the description which follows, referring to different embodiments given by way of indicative and nonlimiting examples.

Understanding this description will be facilitated in. referring to the attached drawing in which: Figure 1 is a schematic perspective view of the closure device according to the invention;

Figures 2 and 3 are schematic side views corresponding in detail to this device, respectively in the open and closed position of the conduit by the valve;

Figure 4 corresponds to a schematic view, in perspective and in detail, of the valve.

The invention relates to the field of the automobile industry and, more particularly, that of equipment making it possible to ensure the escape of gases resulting from the combustion of a fuel within an internal combustion engine.

Such equipment is in the form of an exhaust line comprising at least one duct 1 which defines a passage for the exhaust gases and inside which these gases circulate.

In this regard, it will be observed that such a duct 1 is preferably associated with a muffler 2 which usually comprises such an exhaust line, this muffler 2 being designed capable of reducing the noise emissions of said engine and of this exhaust line.

In fact and according to a first embodiment, such a conduit

1 extends, at least in part, inside such a silencer 2 in which it takes the form of a portion of tube whose end opens into the internal volume of this silencer 2.

This portion of tube is preferably made integral with a cup which includes, internally, such a silencer 2.

However and according to another embodiment, such a duct 1 can also be defined by an opening made at the level of such an internal muffler cup 2, this opening delimiting a passage- of the exhaust gases and opening inside this silencer 2.

In this regard, it should be noted that, in the following description, reference will more particularly be made to a conduit 1 adopting the shape of a portion of tube knowing that the present invention is in no way limited to such an embodiment and that such a duct 1 can, again and in a nonlimiting manner, adopt the form of an opening as mentioned above.

The invention therefore relates to a device 3 intended for closing off one end 4 that. has such a gas passage duct 1.

This shutter device 3 comprises, on the one hand, a valve 5 associated with means 6 arranged to ensure a pivoting mounting of this valve 5 relative to said conduit 1, such mounting means 6 allowing this valve to pivot 5 between a closed position (FIG. 3) of the duct 1 and at least one open position (fiçpire 2) of this duct 1.

In fact, such mounting means 6 comprise a support 7 made integral with said conduit 1 or (and preferably as visible in the appended figures) of said silencer 2, more particularly of a cup which, internally, comprises such a silent 2.

This support 7 is preferably defined by a yoke 8 and comprises two uprights 9, 9 'on which said valve 5 is pivotally mounted. To do this, said mounting means 6 also comprise a shaft 10, either integral of the support 7 (more particularly, of at least one of the said uprights 9, 9 ') and on which the ILedit valve 5 is pivotally mounted, or integral with the valve 5 and pivotally mounted on the support 7 (more particularly on the said uprights 9, 9 'of the support 7) as shown in FIG. 1.

Said shutter device 3 comprises, on the other hand, means 11 for returning said valve 5 to the closed position of this duct 1. Such return means 11 are arranged for, on the one hand and for a pressure of the gas inside the duct 1 greater than a determined pressure value, authorize the opening or maintaining in the open position of said valve 5.

These return means 11 are arranged for, on the other hand and for a gas pressure below this determined pressure value, ensuring the maintenance or return of the valve 5 in a position for closing this duct 1.

According to another characteristic of the invention, this device 3 can also include means arranged to limit the amplitude of the pivoting of said valve 5 when the duct 1 is opened.

Such amplitude limitation means can be constituted, either by at least one stop that comprises said device 3 (in particular at the level of the mounting means 6 of said valve 5, more particularly at the level of said support 7, or even of at least one of said uprights 9, 9 ′) and against which said valve 5 comes to bear, either by said return means 11 themselves.

In this regard, it will be observed that these return means 11 are usually defined by a return spring 12 which preferably takes the form of a coil spring comprising a certain. number of turns, in particular characteristic of the value of the. preload of this spring 12. Such a return spring 12 is preferably engaged around the shaft 10 of the means 6 for pivotally mounting the valve 5. Also and according to the invention, the closure device 3 comprises means 13 arranged to, at least in the open position of the duct 1, deflect the flow of the exhaust gases coming from this duct 1, this relative to the means 11 and so as to prevent the exhaust gases from reaching the latter 11.

According to a preferred embodiment, said means 13 for deflecting the flow of gases consist of a deflector 14 interposed between the means 11 for returning the valve 5 and the conduit 1.

More particularly and as visible in the appended figures, such a deflector 14 is interposed between the means 11 for returning the valve 5 and the open end 4 of said duct 1 at the level of which the exhaust gases exit from said duct 1. This deflector 14 is preferably arranged on the path adopted by the exhaust gases at the outlet of this duct 1.

According to a first type of embodiment not shown, said deflector 14 is defined by an additional element associated with the duct 1, with the valve 5, with the mounting means 6 associated with this valve 5, with the return means 11 with valve 5, or even with the muffler 2 that includes the exhaust line.

Thus, a particular embodiment may consist in that such a deflector 14 is defined by a flap made integral, in particular by welding or the like, of the duct 1, of the valve 5, of the mounting means 6 or also of the silencer 2.

Such a flap can thus be made integral with the support 7 of the mounting means 6, more particularly at the level of a base 15 and / or at least one of the uprights 9 that the yoke 8 constituting such a support 7 . However and according to a preferred embodiment, such an additional element is associated with the means 6 for mounting the valve or with the means 11 for returning the latter 5. Such an additional element can then be constituted by means capable of ensuring a cowling of at least part of these means 11 for returning the valve 5. Such cowling means may be in the form of a cylindrical envelope disposed over the spring 12 constituting these means 11.

However, according to another type of embodiment, the means 13 for deflecting the flow of gases consist of a deflector 14 defined at the level of said valve 5 or means 6 for pivotally mounting the latter 5. Such a deflector 14 is produced, preferably, by deformation of said valve 5 or of these mounting means 6, in particular by stamping of this 5 or these 6.

Thus and according to a first embodiment not shown, such a deflector 14 is in the form of a flap defined at the level of the support 7 of the mounting means 6, more particularly at the level of the base 15 and / or the at least one of the uprights 9, 9 'that has the yoke 8 constituting such a support 7. Such a flap can be produced during the manufacture of such a support 7, this by deformation (stamping or the like).

According to an additional characteristic, the shutter device 3 is designed so that the deflector 14 is positioned externally to said duct 1. (in particular externally to the portion of tube constituting this duct 1) and so that, in the open position of this duct 1, the valve 5 can come into abutment against this deflector 14 which then constitutes means for limiting the tilting amplitude of the valve 5.

However and according to a preferred embodiment of the invention visible in FIGS. 1 to 4, the deflector 14 is defined at the level of said valve 5, this by deformation and / or cutting (in particular during a stamping operation or the like), more particularly during the manufacture of this valve 5.

In this regard, it should be observed that this valve 5 comprises a portion 16 arranged to ensure the obturation of the conduit 1 (in particular by cooperating with the end 4 opening out of the tube portion) while the deflector 14 is located in the extension of this shutter portion 16.

According to another characteristic, the portion 16 of the valve 5 intended for closing the conduit 1 extends substantially in a plane while the deflector 14 deviates from this plane.

According to a first embodiment not shown, this deflector 14 can be arranged, at the level of said valve 5, so as to diverge relative to the conduit 1 to be closed, or even to be oriented in the direction of the return means 11 of this valve 5 .

However and according to a preferred embodiment of the invention, this deflector 14 is arranged, at the level of said valve 5, so that, at least in the opening position of the duct 1 by this valve 5, this deflector 14 is oriented in direction of said duct 1 or also extends substantially parallel to the axis of this duct 1, or even extends in the direction of said duct 1.

A preferred embodiment consists of this deflector 14 is oriented in the direction of said duct 1 whatever the position of the valve 5 relative to this duct 1 (FIGS. 1 to 3).

According to an additional characteristic, the shutter device 3 is designed so that the deflector 14 is positioned externally to said conduit 1 (in particular externally to the portion of tube constituting this conduit 1) and so that, in the open position <ie this duct 1, this deflector 14 can come into abutment against this duct 1 which then constitutes means for limiting the tilting amplitude of the valve 5.

In fact, such a deflector 14 can be in the form of a flap extending substantially in a plane forming an angle with the plane of said shutter portion 16.

Another embodiment visible in the appended figures consists in that said deflector 14 has a curved shape, in particular concave. In this regard, it will be observed that the plane in which the shutter portion 16 of the valve 5 extends is positioned, then, tangentially; to the curvature of this deflector 14 and in the extension of this? last 14.

As visible in the appended figures, the concavity of the curvature of the deflector 14 is oriented in ", direction of the duct 1.

According to an additional characteristic of the invention, the valve 5 consists of a single piece at which the shutter portion 16, the deflector 14 as well as pierced ears 17, 17 'constituting, in part, are defined. the pivoting mounting means 6 of this valve 5 and intended to receive a shaft 10.

This valve 5 is preferably made from a plate or a sheet, in particular metallic (for example sheet metal), more particularly by cutting and / or defo-cmation (in particular by stamping or by folding) of so as to define the closing portion 16, the deflector 14 and the lugs 17, 17 ′ which the pivoting mounting means 6 comprise. In this regard, it will be observed that said deflector 14 is, then and preferably, defined by cutting followed by deformation, in particular by folding, of said plate or of said sheet.

According to another characteristic of the invention, during the manufacture of the valve 5 from a plate or a sheet, two cutting lines are made making it possible to delimit, on the one hand and between these two lines of cutting, a portion intended to constitute after deformation (in particular by folding) the deflector 14 of the valve 5 and, on the other hand and externally to these two cutting lines (therefore on either side of the portion intended to constitute the deflector 14), two portions intended to constitute after deformation (in particular by folding) the ears 17, 17 ′ which comprise the means for pivotally mounting 6 of the valve 5.

According to another characteristic of the invention, this relates, again, to a silencer 2 comprising, on the one hand, a conduit 1 delimiting a passage for the exhaust gases, and, on the other hand and at this conduit 1 (more particularly at its end 4), a closure device 3 of the aforementioned type.

Finally, the invention also relates to a gas exhaust line associated with an internal combustion engine and comprising, in particular at the level of a muffler 2 that such an exhaust line comprises, a duct 1 delimiting a gas passage. This gas exhaust line comprises, at said conduit 1 (more particularly at its end 4), a closure device 3 of the aforementioned type.

Claims

1. Device (3) for closing off the end (4) of a duct (1) which comprises an exhaust line of an internal combustion engine and which defines a passage for the exhaust gases, this device (3 ) comprising, on the one hand, a valve (5) associated with means (6) for pivotally mounting authorizing pivoting of this valve (5) between a closed position and at least one position for opening the duct ( 1) and, on the other hand, means (11) for returning said valve (5) to the closed position of this duct (1), characterized in that it comprises means (13) arranged to, at least in the open position of the duct (1), divert the flow of exhaust gases from this duct (1), this with respect to the return means (11) and so as to avoid that the gases reach the latter (11). 2. Device (3) for closing according to claim 1, characterized in that the means for deflecting (13) the flow of gases consist of a deflector (14) interposed between the return means (11) of the valve ( 5) and the conduit (1), in particular the through end of the latter (1). 3. Device (3) for closing according to claim 2, characterized in that the deflector (14) is disposed on the path adopted by the exhaust gases at the outlet of this conduit (1). 4. Device (3) for closing according to any one of claims 2 or 3, characterized in that the deflector (14) is defined by an additional element associated with the duct (1), with the valve (5), with the mounting means (6) associated with the latter (5), with the return means (11) thereof, or still to a part of the silencer (2) that includes the exhaust line. 5. Device (3) for closing according to claim 4, characterized in that the deflector (14) is associated with the mounting means (6) of the valve (5) or with the return means (11) of the latter ( 5) and is constituted by means capable of ensuring a cowling of at least part of these return means (11) of the valve (5). 6. device (3) for closing according to any one of claims 1 to 3, characterized in that the means (13) for deflecting the flow of gases are constituted by a deflector (14) defined at said valve ( 5) or mounting means (6) for pivoting the latter (5). 7. Device (3) for closing according to claim 6, characterized in that the deflector (14) is produced by deformation of said valve (5) or mounting means (6), in particular by stamping. 8. Device (3) for closing according to any one of claims 6 or 7, characterized in that the valve (5) has a portion (16) arranged to ensure the closing of the conduit (1) while the deflector (14) is defined at the level of this valve (5) and is located in the extension of this shutter portion (16). 9. Device (3) for closing according to claim 8, characterized in that the portion (16) of the valve (5) intended for closing the duct (1) extends substantially in a plane while the deflector (14) deviates from this plane and either forms an angle with this plane or has a curvature at which this plane is positioned tangentially. 10. Device (3) for closing according to any one of claims 8 or 9, characterized in that the deflector (14) is arranged, at said valve (5), so that, at less in the open position of the duct (1) by this valve (5), this deflector (14) is oriented in the direction of said duct (1) or even extends substantially parallel to the axis of this duct (1), or even extends in the direction of said conduit (1). 11. device (3) for closing according to any one of claims 8 to 10, characterized in that the valve (5) is produced from a plate or a sheet, in particular a metal, by cutting and / or deformation so as to define the shutter portion (16), the deflector (14) and ears (17, 17 ') that comprise the pivoting mounting means (6). 12. Device (3) for closing according to any one of claims 8 to 11, characterized in that the valve (5) is made from a plate or a sheet, in particular metallic, at which two cutting lines are produced making it possible to delimit, on the one hand and between these two cutting lines, a portion intended to constitute, after deformation, the deflector (14) of the valve (5) and, on the other hand and externally to these two cutting lines, two portions intended to constitute after deformation of the ears (17, 17 ') that comprise the means for pivotally mounting (6) of the valve (5). 13. Device (3) for closing according to any one of claims 2 to 12, characterized in that the device (3) for closing is designed so that, in the open position of the conduit (1), the valve (5), respectively the deflector (14), can come into abutment against the deflector (14), respectively against the duct (1), which constitutes means for limiting the tilting amplitude of the valve (5). 14. Muffler (2) which comprises a gas exhaust line associated with an internal combustion engine and which comprises a conduit (1) delimiting an exhaust gas passage, characterized by the fact that this silencer (2) comprises, at the level of said duct (1), a device (3) for closing off this duct (1) according to any one of claims 1 to 13. 15. Gas exhaust line associated with an internal combustion engine and comprising, in particular at the level of a silencer (2) that includes such an exhaust line, a duct (1) delimiting a gas passage, characterized by the fact that this exhaust line comprises, at the level of said duct (1), a device (3) for closing off this duct (1) according to any one of claims 1 to 14.