DE10047815A1 - Device for supplying exhaust gases from an internal combustion engine to a catalytic converter, in particular a storage catalytic converter - Google Patents

Abstract

The invention relates to a device (10) for supplying exhaust gases from an internal combustion engine to a catalyst (11), in particular a storage catalyst, said device (10) containing multiple exhaust gas supply lines (12). The invention is characterised in that at least one exhaust gas supply line (12) is configured as a thermal conductor (13) for the beneficial transmission of exhaust gas heat to the catalyst (11) and at least one other exhaust gas supply line (12) is configured as a heat exchanger (14) upstream of the catalyst (11) for the beneficial extraction of exhaust gas heat. Controllable regulating means (15) are provided to regulate the cross-sectional flow of at least one of the exhaust gas supply lines (12).

Description

The invention relates to a device for supplying exhaust gases from a Internal combustion engine to a catalyst, in particular storage catalyst, the Device contains a plurality of exhaust gas supply line, according to the preamble of Claim 1.

For converting nitrogen oxides contained in exhaust gases in gasoline engines with direct Fuel injection of a vehicle is preferably a NOx storage catalytic converter used, which, however, only in a relatively narrow Exhaust gas temperature windows provide sufficiently high conversion rates. this leads to a disadvantageous limitation of the low-efficiency lean operating range of an Otto combustion engine. For optimal reduction of fuel consumption The exhaust system of direct injection petrol engines by means of lean operation is such to match the engine that the exhaust gas temperatures immediately before entering the storage catalytic converter with the largest possible engine operating range within of a defined working temperature window. The upper limit of this Working temperature window will appear at higher vehicle speeds or at higher engine loads. If this upper limit is exceeded The temperature limit will determine the functionality and the service life (durability) of the Storage catalytic converter adversely affected. That is why the exhaust gases are for expansion the lean operating range of the gasoline engine before entering the storage catalytic converter higher vehicle speeds or higher engine loads cool. On the other hand, it must also be ensured that the storage catalytic converter after a Cold start of the direct injection gasoline engine as quickly as possible Starting temperature, that is the operating temperature at the optimum Pollutant conversion achieved. For this it is necessary to take suitable measures meet which is as low as possible immediately after the cold start of the gasoline engine Heat dissipation from the exhaust gases to the environment before entering the catalytic converter allow.  

DE 199 05 345 A1 discloses a generic device for supplying exhaust gases from an internal combustion engine to an exhaust gas treatment device with a plurality of exhaust gas supply lines. Several exhaust gas supply lines are arranged between a 3-way catalytic converter and a NO _x trap, which should keep a relatively high proportion of the heat in the exhaust gas flow at a relatively low exhaust gas mass flow, while a comparatively higher proportion of the heat is removed with the exhaust gas flow at higher mass flows becomes.

The present invention is therefore based on the object of a generic Specify device which is reliable in a simple and effective manner Adjustment of the exhaust gas temperatures at the entry of the exhaust gases into the catalytic converter is permitted.

This object is achieved by a device with the features of claim 1. This device is characterized in that at least one exhaust gas supply line as heat conduction to favor the transfer of exhaust gas heat to the catalytic converter and at least one other exhaust gas supply line as the heat exchanger for the beneficiary Extraction of exhaust gas heat is formed upstream of the catalytic converter, being a switchable Adjustment means for adjusting a flow cross section of at least one of the Exhaust gas supply lines are provided. Such a device is designed advantageously suitable for the exhaust gas temperatures at the entry into the catalyst the largest possible engine operating range (higher vehicle speeds or higher engine load) as well as immediately after a cold start of the Keep the motor within a defined working temperature window. This is what a switchable adjustment means, which for adjusting a flow cross-section at least one of the exhaust gas supply lines, that is, the heat conduction and / or the Heat exchanger is suitable. The heat conduction serves as fast as possible Reaching the light-off temperature of the catalyst after a cold start of the Otto engine, while the heat exchanger for exhaust gas cooling before the catalyst and thus to prevent an undesired exceeding of the upper one Temperature limit of the working temperature window, especially at higher ones Serves engine loads. For example, when the gasoline engine is cold started possible that the heat conduction is open (maximum flow cross section) to a to allow maximum transfer of exhaust heat to the catalyst, and the Heat exchanger is partially or completely closed, so that as little as possible Exhaust gas heat is transferred to the environment in front of the catalytic converter but to Heating of the catalyst is used, which as soon as possible after the cold start  the gasoline engine should reach its light-off temperature. If the catalyst is its Has reached light-off temperature and the gasoline engine has a higher engine load (higher vehicle speeds), it is advantageous to Open the heat exchanger partially or completely and, if necessary, the Partially or completely seal heat conduction to prevent due to excessive heat transfer through the exhaust gas to the catalyst upper temperature limit of the working temperature window is exceeded. All of these on Settings adapted to the respective engine operating range in relation to the Flow cross-section of one or more exhaust gas supply lines for control or regulation of the heat transfer through the exhaust gas to the catalytic converter can be adjusted in a simple, precise and reliable manner by means of a switchable adjustment means Realize wisely.

The exhaust gas supply lines are preferably separate tubes educated. Because the exhaust gas supply lines are two different respectively should pursue opposite goals, that is, the best possible transfer of Exhaust gas heat to the catalyst (heat conduction) and a reduced as possible Transfer of exhaust gas heat to the catalytic converter (heat exchanger), depending on the respective engine operating range (cold start, higher engine load), it is advantageous to Exhaust gas supply lines as separate from one another and preferably also slightly to form spaced tubes. By separating the heat conduction from Heat exchanger can be a particularly effective setting of heat transfer through the exhaust gases to the catalytic converter.

According to one embodiment of the invention, the one designed as heat conduction Exhaust gas supply line in relation to that designed as a heat exchanger Exhaust gas supply line has a smaller flow cross-section. In this way, the Exhaust heat transfer area related to the environment in front of the catalytic converter limited to as little as possible on the heat conduction and with regard to the Heat exchanger are formed as large as possible.

The exhaust gas supply lines are advantageously spaced apart from one another as a tube bundle arranged, the supply line designed as a heat pipe in the tube bundle arranged on the inside and formed by a plurality of heat exchangers Exhaust gas supply lines are surrounded circumferentially. Grouped as a tube bundle and Exhaust gas supply lines spaced apart from one another allow a compact design  the device. Here are the trained as a heat exchanger Exhaust gas supply lines preferably outside and circumferential around the internal heat conduction or heat conduction to one as possible to enable effective heat exchange of the heat exchanger with the environment.

The exhaust gas supply line, which is designed as a heat conduction, is advantageously equipped with a Provide thermal insulation. It is in by means of thermal insulation of the heat conduction particularly easy and effective way possible, the exhaust heat transfer to the To reduce the environment to a minimum by heat conduction and thus a to ensure the best possible transfer of exhaust gas heat to the catalytic converter. This has a particularly advantageous effect when the gasoline engine is cold started rapid heating of the catalyst to its light-off temperature.

According to a preferred embodiment, it extends as heat conduction trained exhaust gas supply line up to just before the matrix of the catalyst. By this measure can quickly heat up a locally limited area of the Catalyst matrix can be achieved in order to get the light-off temperature of the To achieve catalyst at which the desired pollutant conversion (including pollutant conversion).

According to a further development of the invention, the heat exchanger is designed as a heat exchanger Exhaust gas supply line structured on its wall such that a Surface enlargement of the heat transfer surface and / or a Turbulence formation of the exhaust gas flow in the exhaust gas supply line is obtained. This serves to reinforce the cooling effect of those designed as heat exchangers Exhaust gas supply line in relation to the exhaust gases to be supplied to the catalytic converter. Through the Turbulence formation of the exhaust gases in the heat exchanger becomes an undesirable training a temperature stratification in the relevant exhaust gas supply line due to a Preventing cold outside flow and hot internal flow of the exhaust gases prevented. Such a temperature stratification is particularly the case with increasing length counteract the corresponding exhaust gas supply line (heat exchanger).

Advantageously, the exhaust gas supply line, which is designed as a heat exchanger, has a Heat-promoting coating provided. By means of such a Coating can be an effective increase in the coating in a relatively simple manner Achieve heat dissipation, in particular radiant heat dissipation, to the environment.  

According to a preferred embodiment, the outer surface is as a heat exchanger trained exhaust gas supply line with a heat dissipation Outside air flow applied. This will result in an additional increase in Radiant heat dissipation through the heat exchanger to the environment. there can be an external structuring of the wall formed as a heat exchanger Exhaust gas supply line to a desired turbulence of the outside air on the pipe wall lead, whereby a particularly effective heat dissipation through the heat exchanger the environment is preserved. Such an outside air flow can, for example, by targeted guidance of the wind through an inlet opening in the front area of the Vehicle or the underbody capsule of the vehicle can be obtained.

According to a preferred embodiment, the adjusting means has a switching element on, which can be controlled depending on the parameters by means of an adjusting element. For adjustment a flow cross section of at least one of the exhaust gas supply lines Parameters can include the engine coolant temperature, the exhaust gas temperature and / or behind the catalytic converter (as seen in the exhaust gas flow direction), the Be catalyst temperature and / or the exhaust gas mass flow. The exhaust gas mass flow serves as an adjustment parameter, the creation of impermissibly high Avoid exhaust gas back pressure with extremely large exhaust gas mass flows.

The switching element is advantageous as corresponding to the tube bundles Rotating disc provided with through openings. One with corresponding rotating openings provided with suitable through openings is suitable, at the same time and in a precise manner with the appropriate rotation of the respective Flow cross section of preferably several exhaust gas supply lines to be adjusted depending on parameters. This enables a disk-like configuration of the switching element the realization of a particularly compact device.

According to a preferred embodiment, the adjusting element is by means of a electric actuator actuated shift rod. Such a thing trained adjustment element allows a reliable and precise adjustment (Rotation) of the switching element.

Advantageously, the adjustment (rotation) of the disc Switching element by means of a to the given structural conditions  adjusted adjustment element. The adjusting element z. B. as Vacuum can be designed to rotate the switching element more precisely and reliable way to evoke.

According to a further, alternative embodiment, the adjusting element is as electromagnetic adjustment device formed, which has a winding, by means of which the switching element acting as an armature can be set in rotation. Such a trained and functioning adjusting means is characterized by a constructive particularly compact design and at the same time precise and reliable Adjustment of the flow cross section of one or more exhaust gas supply lines.

In addition, the adjusting element can also be designed hydraulically.

The switching element is advantageously adjusted in the form of a two-point circuit. By means of a two-point circuit, the corresponding exhaust gas supply lines are each if necessary (cold start, higher engine load) completely closed or fully opened, optionally between the as heat conduction and the as Heat exchanger trained exhaust gas supply line or lines can be differentiated. A two-point circuit is a Relatively simple circuit for adjusting the switching element.

According to an alternative embodiment, the switching element is adjusted in infinitely adjustable intermediate positions. A stepless adjustment of the Flow cross section of the corresponding exhaust gas supply line or Lines allows a very precise adjustment of the temperature of the catalyst, especially the NOx storage catalytic converter, to an optimal operating temperature a relatively wide engine operating range. Again, you can choose between the Exhaust gas supply lines are distinguished, which have the function of heat conduction or have a heat exchanger.

The exhaust gas supply line, which is designed as a heat conduction, is advantageously coaxial with respect to FIG an axis of rotation of the switching element is arranged. According to this embodiment the device includes heat conduction which is related to the axis of rotation of the Switching element and a corresponding through opening of the switching element coaxially is arranged. A rotation of the switching element thus does not cause any adjustment of the Flow cross section of the heat conduction, but only the flow cross sections  the external exhaust gas supply lines designed as heat exchangers. The According to this embodiment, heat conduction is therefore always in one open state, while those designed as heat exchangers Exhaust gas supply lines (or exhaust gas supply line) by adjusting the Switching element opened in relation to the supply of exhaust gases to the catalyst, can be closed or possibly partially closed.

According to an alternative embodiment, that is designed as heat conduction Exhaust gas supply line radially spaced with respect to an axis of rotation of the switching element arranged. In this embodiment, the flow cross sections of both Heat conduction and the outside heat exchanger when adjusting the Switching element changed because all through openings of the switching element in relation are spaced on the axis of rotation and thus upon rotation of the switching element a relative displacement of all through openings with respect to the corresponding Create openings in the flue gas supply lines (heat pipe and heat exchanger).

The switching element advantageously has a central disk and one with respect to the Disc coaxial, outer and rotatable relative to the disc ring, the Disc according to the as heat conduction and the ring according to the as Heat exchanger-trained exhaust gas supply lines with through openings is provided. In this way it is possible that the disc and the ring to Adjustment of the corresponding flow cross sections of the associated Exhaust gas supply lines (heat conduction, heat exchanger) using an adjustment element can be controlled independently of one another, so that the desired operating temperature of the catalyst can be adjusted in an extremely precise manner.

The switching element designed as a disk is preferably directly on the input side arranged in front of the catalyst. This makes a constructive proportion simple design of the device enables at least as Exhaust gas supply line or lines designed only for heat exchangers one-sided (with respect to the switching element on the input side) with the respective The through hole of the switching element is in operative contact.

In the following, the invention is described on the basis of several preferred exemplary embodiments described with reference to the drawings. Show it:

Figure 1 is a schematic side view of a partially shown and connected to a catalyst exhaust gas supply device.

Fig. 2 is a schematic front view according to section line II-II of the device corresponding to Fig. 1;

Fig. 3 is a schematic front view of an alternative embodiment of the device;

Fig. 4, 6, 8, 10, 12 is a schematic side view of various Ausfüh approximate forms of a heat exchanger formed as a gas supply line, and

Fig. 5, 7, 9, 11, 13 is a schematic front view of the exhaust gas supply line according to Fig. 4, 6, 8, 10 and 12.

In particular a NOx storage catalytic converter Fig. 1 shows a generally designated 10, apparatus for feeding exhaust gases from an internal combustion engine of a vehicle (not shown) to a catalytic converter 11. The device 10 contains a plurality of exhaust gas supply lines 12 , which are connected on the input side to a common exhaust pipe 25 and on the output side lead to the catalytic converter 11 with the interposition of a switchable adjusting means 15 . The exhaust gas supply lines 12 are designed as separate tubes and are spaced apart from one another as a tube bundle, an exhaust gas supply line 12 designed as a heat conduit 13 being arranged inside the tube bundle and surrounded circumferentially by a plurality of exhaust gas supply lines 12 designed as a heat exchanger 14 . The exhaust gases are fed according to the arrow line 26 from the internal combustion engine, not shown, through the exhaust pipe 25 to the respective exhaust gas supply lines 12 corresponding to the arrow lines 27 , 28 , 29 , which, when the adjusting means 15 is switched appropriately, to the catalytic converter in accordance with the arrow lines 30 , 31 , 32 11 forward. The formed as a heat pipe 13 exhaust gas supply line 12 is used for the transmission recipient of exhaust gas heat to the catalytic converter 11 while the designed as a heat exchanger 14 Abgaszuführleitungen 12 are provided toward the favored withdrawal of exhaust gas heat upstream of the catalyst. The switchable adjusting means 15 is suitable for varying the flow cross section of the respective exhaust gas supply lines 12 designed as heat exchangers 14 .

According to FIG. 2, the adjusting means 15, a switching element 17 which is a function of parameters controllable by means of an adjusting 23rd The switching element 17 is designed as a disk which can be rotated in a housing 18 about an axis of rotation 19 according to the arrow lines 20 and 21 and which is provided with through-openings 22 , 36 in accordance with the arrangement of the exhaust gas supply line 12 to form a tube bundle. The through openings 22 in a specific switching position of the adjusting means 15 and the rotatable shift member 17 are aligned with respect to the designed as a heat exchanger 14 Abgaszuführleitungen 12 (see also Fig. 1). According to the embodiment of Fig. 1 and 2, the passage 36 disposed independently of the switching position of the adjusting means 15 and the switching element 17 in alignment with respect to the exhaust gas supply line designed as a heat line 13 12th

As shown in FIGS. 1 and 2, the exhaust gas supply line 12 designed as a heat pipe 13 preferably has a smaller flow cross section than the exhaust gas supply lines 12 designed as a heat exchanger 14 . In this way, the heat conduction 13 results in a relatively small transfer of exhaust gas heat to the surroundings (small heat transfer area of the heat conduction 13 ). By contrast, the exhaust gas supply lines 12 designed as heat exchangers 14 have the largest possible heat transfer area in order to promote effective heat transfer to the surroundings. The exhaust gas supply line 12, which is designed as a heat pipe 13 , is also provided with thermal insulation 16 (see FIG. 1) in order to be able to transfer as much exhaust gas heat as possible to the catalytic converter 11 . The heat conduction 13 preferably extends right up to the matrix (not shown) of the catalytic converter 11 in order to enable a locally limited area of the catalytic converter matrix to heat up as quickly as possible.

The exhaust gas supply lines 12 designed as heat exchangers 14 are preferably structured on their walls in such a way that an increase in the surface area of the heat transfer surface and / or turbulence of the exhaust gas flow (arrow line 28 , 29 in FIG. 1) is obtained in the respective exhaust gas supply line 12 . In Figs. 4 to 13 different possibilities of such a structure are illustrated. Which is designed as heat exchanger 14, exhaust gas supply line 12 as shown in FIGS. 4 and 5 is arranged with external, circumferentially uniformly distributed evenly and provided outwardly projecting ridges 33. The ribs 33 serve to increase the surface area of the heat transfer surface of the exhaust gas supply line 12 and thus to improve heat transfer to the surroundings. FIGS. 6, 7 show a heat exchanger 14 configured as exhaust gas supply line 12 which has a changing in the longitudinal extension ovality. This leads to an increase in surface area as well as to the formation of turbulence in the exhaust gas stream flowing through the exhaust gas supply line 12 . In Figs. 8, 9, a wave-shaped in the longitudinal direction of exhaust gas supply line 12 is shown. Here, too, an increase in surface area and turbulence formation of the exhaust gas flow in the exhaust gas supply line 12 are obtained. The exhaust gas supply line 12 as shown in FIGS. 10, 11 is shaped circumferentially provided with inwardly extending impressions 34, whereby both an increase in surface area of the heat transfer area and a turbulence of the flowing exhaust gas stream is obtained. The Fig. 12, 13 show an exhaust gas supply line 12, which is internally provided with beads 35, wherein the beads may also be slanted in the flow direction 35. The beads 35 serve to turbulence of the exhaust stream in the exhaust gas supply line 12 and at the same time allow an increase in surface area of the heat transfer area of the exhaust gas supply line 12th According to an embodiment not shown, the exhaust gas supply lines 12 designed as heat exchangers 14 for increasing the turbulence in cross section can also be designed as rectangular, triangular, semicircular or semi-oval tubes. The turbulence generation in the exhaust gas supply lines 12 designed as a heat exchanger 14 serves in particular to increase the heat transfer from the hot exhaust gas to the outer wall of the corresponding exhaust gas supply line 12 . Furthermore, a turbulence formation of the exhaust gas in the exhaust gas supply line 12 prevents a temperature stratification which forms with increasing line length, that is to say the formation of an external cold exhaust gas flow and an internal hot exhaust gas flow.

According to an embodiment which is not shown, the exhaust gas supply lines designed as heat exchangers 14 can be provided with a coating which promotes heat dissipation and / or their optionally structured outer surface can be acted upon by an outside air flow which promotes heat dissipation.

The device 10 according to FIGS. 1 and 2 works according to the following functional principle: When the internal combustion engine is cold started or in an engine warm-up phase, i.e. in a phase in which the catalytic converter has not yet reached its light-off temperature, the adjusting means 15 is switched in such a way that By means of a corresponding rotation of the switching element 17 about the axis of rotation 19, the flow through the exhaust gas supply lines 12 designed as a heat exchanger 14 is completely or at least partially blocked. In this switching position of the switching element 17 , the through openings 22 are thus no longer aligned with respect to the exhaust gas supply lines 12 designed as heat exchangers 14 . The internal heat conduction 13 remains open even in this switching position of the switching element 17 , since it is arranged coaxially with respect to the axis of rotation 19 of the switching element 17 . In this switch position, hot exhaust gas is conducted according to arrow lines 26 , 27 through heat conduction 13 along arrow line 30 into catalytic converter 11 . When the catalyst 11 has reached its light-off temperature, the switching element is so rotated 17 by means of the adjusting element 23 according to the arrow lines 20 and 21 about the rotational axis 19 until alignment of the through holes 22 with the appropriate, designed as a heat exchanger 14 Abgaszuführleitungen 12th In this switching position, hot exhaust gas is conducted into the heat exchanger 14 according to the arrow lines 26 , 28 , 29, in order to be cooled there and to be passed on to the catalytic converter 11 as a cold partial exhaust gas flow according to the arrow lines 31 , 32 . The hot exhaust gas flow on the input side (arrow line 26 ) is thus converted on the output side into a hot partial exhaust gas flow (arrow line 30 ) and a plurality of cold partial exhaust gas flows (arrow lines 31 , 32 ). Because of the parameter-dependent circuit of the adjusting means 15 ensures that the catalyst 11 reaches quickly its light-off temperature, to allow without any major delay times a correct nitrogen oxide conversion, and that the catalyst 11 after reaching its light-off temperature at higher engine loads are not an upper temperature limit of a defined exhaust gas temperature window, within which a correct and effective conversion of nitrogen oxide by the catalyst 11 can take place.

In particular, the coolant temperature of the engine, the exhaust gas temperature in the flow direction upstream and / or downstream of the catalytic converter, the catalytic converter temperature and / or the exhaust gas mass flow serve as switching parameters. Since inadmissibly high exhaust gas back pressures can still occur during high catalyst mass flows during the catalyst heating phase, the exhaust gas supply lines 12 designed as heat exchangers 14 must be opened partially or completely by suitable switching of the adjusting means 15 even at a catalyst temperature below the light-off temperature.

The switching element 17 is preferably adjusted in continuously adjustable intermediate positions. An infinitely precise and variable setting of the operating temperature of the catalytic converter 11 can be achieved by steplessly releasing the respective flow cross sections of the exhaust gas supply lines 12 designed as heat exchangers 14 as a function of the switching parameters mentioned above. In particular, in the case of high mass flows during the catalyst heating phase, it can be avoided that the cooling capacity increases too much by completely opening the exhaust gas supply lines 12 designed as heat exchangers 14 and thus preventing the catalytic converter from starting quickly. However, it is also conceivable for the switching element 17 to be adjusted in the form of a two-point circuit. In the case of a two-point circuit, the corresponding exhaust gas supply lines 12 are either completely opened or completely closed by switching the adjusting means 15 .

An alternative embodiment with regard to the number and arrangement of the heat conduction 13 is shown in FIG. 3. According to this embodiment, two through openings 36 which are separate from one another and spaced apart from one another are provided on the switching element 17 . The through openings 36 are arranged radially spaced with respect to the axis of rotation 19 of the switching element 17 . The device 10 is provided in a corresponding manner with two heat pipes 13 (not shown in the figures). Such an arrangement of the through openings 36 and the associated heat lines 13 causes the respective flow cross section of both the heat exchanger 14 and the exhaust gas supply lines 12 designed as heat pipe 13 to be adjusted when the switching element 17 rotates about the axis of rotation 19 . The cooling capacity of the device 10 is thus increased, since the flow cross section of the internal heat lines 13 can also be changed by switching the adjusting means 15 . The number of exhaust gas supply lines 12 designed as heat exchangers 14 and the heat supply lines 13 and their flow cross sections can be adapted to the respective application.

According to a further alternative embodiment, not shown, the switching element 17 has a central disk and an outer ring which is coaxial with respect to the disk and which can be rotated relative to the disk, the disk corresponding to the heat conduits 13 and the ring corresponding to the heat exchanger 14 trained exhaust gas supply lines 12 is provided with through openings 22 , 36 . This alternative embodiment enables the flow cross sections of the heat lines 13 on the one hand and the exhaust gas supply lines 12 in the form of heat exchangers 14 to be set independently. In the event that the catalytic converter 11 exceeds a fixed upper temperature limit despite the open exhaust gas supply lines 12 designed as a heat exchanger 14 , the through openings 36 can be partially or completely closed by adjusting the switching element 17 . The rotation of the central disk and the outer ring can be generated by means of two separate adjustment elements or by means of a single, suitably designed adjustment element.

According to an alternative embodiment, the adjusting element 23 can be designed as a vacuum box or also as an electromagnetic adjusting device which has a winding, by means of which the switching element 17 acting as an armature can be set in rotation.

The switching element 17, which is designed as a disk, is arranged directly upstream of the catalytic converter 11 .

If the exhaust gas temperature or the catalyst temperature fall below a fixed lower limit value, the exhaust gas supply lines 12 designed as heat exchangers 14 can be partially or completely closed by appropriate adjustment of the switching element 17 by the adjusting element 23 .

The respective values of the switching parameters can be determined and processed accordingly and, if necessary, an automatic switching of the adjusting means 15 can be initiated by measuring means and a central control unit, which are not shown and are known per se.

Claims (20)

1. Device for supplying exhaust gases from an internal combustion engine to a catalytic converter, in particular storage catalytic converter, wherein the device contains a plurality of exhaust gas supply lines, characterized in that at least one exhaust gas supply line ( 12 ) acts as a heat pipe ( 13 ) for favorably transferring exhaust gas heat to the catalytic converter ( 11 ) and at least one other exhaust gas supply line ( 12 ) is designed as a heat exchanger ( 14 ) for favorably extracting exhaust gas heat upstream of the catalytic converter ( 11 ), a switchable adjusting means ( 15 ) being provided for adjusting a flow cross section of at least one of the exhaust gas supply lines ( 12 ). 2. Device according to claim 1, characterized in that the exhaust gas supply lines ( 12 ) are designed as separate tubes. 3. Device according to one of the preceding claims, characterized in that the heat formed as a pipe (13) exhaust gas supply line (12) has a smaller with respect to the designed as a heat exchanger (14) exhaust gas supply line (12) the flow cross-section. 4. Device according to one of the preceding claims, characterized in that the exhaust gas supply line (12) spaced from one another are arranged as a tube bundle, which is constructed as heat conduction (13) exhaust gas supply line (12) internally disposed in the tube bundle and a plurality of the heat exchanger (14 ) formed exhaust gas supply lines ( 12 ) is surrounded circumferentially. 5. Device according to one of the preceding claims, characterized in that the waste gas supply line ( 12 ) designed as a heat pipe ( 13 ) is provided with heat insulation ( 16 ). 6. Device according to one of the preceding claims, characterized in that the exhaust gas feed line ( 12 ) designed as a heat pipe ( 13 ) extends up to directly in front of the matrix of the catalyst ( 11 ). 7. Device according to one of the preceding claims, characterized in that the designed as a heat exchanger (14) exhaust gas supply line (12) is structured at its wall that a surface enlargement of the heat transfer area and / or turbulence of the exhaust stream in the exhaust gas supply line (12) to receive becomes. 8. Device according to one of the preceding claims, characterized in that the exhaust gas supply line ( 12 ) designed as a heat exchanger ( 14 ) is provided with a coating which promotes heat dissipation. 9. Device according to one of the preceding claims, characterized in that the outer surface of the exhaust gas supply line ( 12 ) designed as a heat exchanger ( 14 ) is acted upon by an outside air flow which promotes heat dissipation. 10. Device according to one of the preceding claims, characterized in that the adjusting means ( 15 ) has a switching element ( 17 ) which can be controlled in a parameter-dependent manner by means of an adjusting element ( 23 ). 11. Device according to one of the preceding claims, characterized in that the switching element ( 17 ) is designed as a rotatable disk provided with through openings ( 22 , 36 ) corresponding to the tube bundle. 12. Device according to one of the preceding claims, characterized in that the adjusting element ( 23 ) is designed as a switch rod ( 24 ) which can be actuated by means of an electric actuator. 13. Device according to one of the preceding claims, characterized in that the adjusting element ( 23 ) is designed as a vacuum box. 14. Device according to one of the preceding claims, characterized in that the adjusting element ( 23 ) is designed as an electromagnetic adjusting device which has a winding by means of which the switching element ( 17 ) acting as an armature can be set in rotation. 15. Device according to one of the preceding claims, characterized in that the adjustment of the switching element ( 17 ) takes place in the form of a two-point circuit. 16. Device according to one of the preceding claims, characterized in that the adjustment of the switching element ( 17 ) takes place in infinitely adjustable intermediate positions. 17. Device according to one of the preceding claims, characterized in that the exhaust gas supply line ( 12 ) designed as a heat pipe ( 13 ) is arranged coaxially with respect to an axis of rotation ( 19 ) of the switching element ( 17 ). 18. Device according to one of the preceding claims, characterized in that the exhaust gas supply line ( 12 ) designed as heat conduction ( 13 ) is arranged radially spaced with respect to an axis of rotation ( 19 ) of the switching element ( 17 ). 19. Device according to one of the preceding claims, characterized in that the switching element ( 17 ) has a central disk and a ring which is coaxial with respect to the disk, outer and rotatable relative to the disk, the disk corresponding to the heat conduction ( 13 ) and Ring is provided with through openings ( 22 , 36 ) corresponding to the exhaust gas supply lines ( 12 ) designed as heat exchangers ( 14 ). 20. Device according to one of the preceding claims, characterized in that the switching element ( 17 ) designed as a disc is arranged directly on the input side in front of the catalytic converter ( 11 ).