Turbocharger

Abstract

The present invention relates to a turbocharger (1) comprising a compressor structure (2) for compressing fresh air of an internal combustion engine, a compressor housing (20) having a fresh air inlet (201) and a fresh air outlet (202) and in which a compressor impeller (32) is arranged, an exhaust gas turbine (3) for driving the compressor structure (2), a turbine housing (30) having an exhaust gas inlet (301) and an exhaust gas outlet (302) and in which a turbine wheel (32) is arranged, and a heated catalytic converter (4) for converting a fuel supplied with the fresh air and / or exhaust gas. The heated catalytic converter (4) comprises a catalytic converter housing (40) having a gas inlet (401), a gas outlet (402) and a fuel inlet (403), and the catalytic converter housing (40) and the compressor housing (20) and / or the turbine housing (30) are in thermal contact with each other on their partial surfaces.

Description

[Technical field]

[0001] The present invention relates to a turbocharger having a compressor arrangement adapted to compress fresh air for an internal combustion engine, the compressor arrangement comprising at least one compressor housing having a fresh air inlet and a fresh air outlet, and at least one compressor impeller disposed within the compressor housing, at least one exhaust gas turbine drives the compressor arrangement, the at least one turbine housing has an exhaust gas inlet and an exhaust gas outlet, and at least one turbine wheel is disposed within the turbine housing. [Background technology]

[0002] It is known in practice that internal combustion engines have at least one turbocharger, which comprises a turbine that extracts kinetic energy from the exhaust gas flow and supplies it as mechanical power. This mechanical power is used to drive a compressor, which supplies the internal combustion engine with fresh air at high pressure, which is required for combustion. This makes it possible to optimize response characteristics, power and / or consumption.

[0003] It is also known in practice to feed exhaust gas from an internal combustion engine to at least one exhaust gas aftertreatment device, which for example has a particulate filter and / or at least one catalytic converter, which either retains soot particles or converts CO, CH X (Chlorhexidine) or NO X It oxidizes or reduces pollutants such as nitrogen oxides, making them harmless.

[0004] All known catalytic converters require operating temperatures higher than normal ambient conditions to adequately remove pollutants from the exhaust gases. Particulate filters function reliably even after a cold start, but need to be regenerated at high temperatures from time to time.

[0005] Thus, International Publication WO 2020 / 193595 A1 discloses a heated catalytic converter designed to convert the supplied fuel with exhaust gas or fresh air. The heated catalytic converter operates in various operating conditions. For example, the supplied fuel is simply vaporized for oxidation in the exhaust gas aftertreatment device, which results in the release of heat and the heating of the exhaust gas aftertreatment device. In another operating condition, at least a part of the fuel is converted to synthesis gas. The synthesis gas has a lower light-off temperature in the exhaust gas aftertreatment device, which improves the heating of the exhaust gas aftertreatment device in some operating conditions of the internal combustion engine. Finally, the fuel is completely converted in the heated catalytic converter to generate hot gas. The hot gas is supplied to the exhaust gas aftertreatment device to heat it.

[0006] A disadvantage of this known heated catalytic converter is that it requires additional installation space, particularly in passenger cars and light commercial vehicles where space is limited. Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the object of the present invention is to provide, based on the prior art, a device for quickly heating an exhaust gas aftertreatment device of an internal combustion engine, which requires little installation space and is also suitable for retrofitting existing internal combustion engines. [Means for solving the problem]

[0008] The object of the invention is achieved by a turbocharger according to claim 1. Further advantageous developments of the invention are described in the dependent claims.

[0009] According to the invention, a turbocharger is provided, which comprises at least one compressor arrangement and at least one exhaust gas turbine. The compressor arrangement is designed to compress fresh air to be fed to an internal combustion engine. For this purpose, the compressor arrangement comprises at least one compressor housing with a fresh air inlet and a fresh air outlet, and at least one compressor impeller arranged in the compressor housing. Fresh air, which is necessary for the combustion of fuel in the internal combustion engine, is fed to the compressor arrangement from the fresh air inlet at a first pressure and is discharged from the fresh air outlet at a second pressure, the second pressure being higher than the first pressure. The fresh air is thus subjected to mechanical work by the compressor.

[0010] At least one compressor impeller has a number of rotor blades and operates as a radial compressor or an axial compressor. In other embodiments of the present invention, at least one compressor impeller is part of a screw compressor or a roots blower or a swash plate compressor. The present invention does not teach the use of a specific compressor structure design as a solution principle.

[0011] The at least one exhaust gas turbine is designed to drive a compressor structure. For this purpose, the one exhaust gas turbine and the other compressor structure are connected to each other by a rotating shaft, a gearbox, a belt drive or in another manner known per se. The at least one exhaust gas turbine has at least one turbine housing with an exhaust gas inlet and an exhaust gas outlet and at least one turbine wheel arranged in the turbine housing. The exhaust gas turbine is designed to extract energy from the exhaust gas flow and to supply it as mechanical power. In this respect, the exhaust gas flow from the internal combustion engine is fed to the turbine housing via the exhaust gas inlet at a second pressure and discharged via the exhaust gas outlet at a first pressure. The second pressure is higher than the first pressure.

[0012] The turbocharger according to the invention also comprises a heated catalytic converter designed to at least partially convert the fuel supplied with fresh air and / or exhaust gas, the heated catalytic converter comprising a catalytic converter housing with at least one gas inlet and at least one gas outlet and at least one fuel inlet. Fresh air and / or exhaust gas are supplied via the gas inlet. A fuel, for example gasoline or diesel, is supplied to the heated catalytic converter via the fuel inlet. In the heated catalytic converter, product gas is generated from the fuel and the exhaust gas and / or fresh air. For this purpose, the fuel is vaporized in the heated catalytic converter and / or at least partially oxidized with the release of heat and / or converted into synthesis gas by cracking reactions. The product gas thus comprises hot gas and / or fuel vapor and / or synthesis gas. The product gas leaves the heated catalytic converter via a gas outlet and is supplied again to an exhaust pipe downstream of the exhaust gas turbine. Thus, the product gas generated in the heated catalytic converter can be mixed with the exhaust gas by utilizing the turbulence generated by the exhaust gas turbine. The exhaust gas and / or fresh air are fed through the gas inlet at the respective second pressure and discharged into the flowing exhaust gas at the first pressure, resulting in a reliable flow through the catalytic converter housing without the need for additional conveying devices. In some embodiments of the invention, the heated catalytic converter is designed such that the fed fuel is vaporized by the fleece without coking.

[0013] According to the invention, it is proposed that the catalytic converter housing on the one hand and the compressor housing and / or the turbine housing on the other hand are in thermal contact on at least one partial surface. On the one hand, compared to known turbochargers without the additional function of a heated catalytic converter, a turbocharger with an integrated heated catalytic converter requires almost no additional installation space, which leads to a compact design. Furthermore, already used internal combustion engines with a turbocharger can easily be retrofitted with the heating device according to the invention by replacing the existing turbocharger with a turbocharger according to the invention. In this way, additional thermal energy can be introduced into the exhaust gas aftertreatment device without reducing the efficiency of the internal combustion engine by taking measures within the engine.

[0014] Furthermore, by supplying the heated catalytic converter with the waste heat generated during the operation of the turbocharger, the heated catalytic converter itself can reach the operating temperature more quickly, so that the supply of electrical auxiliary energy to the heated catalytic converter can be reduced or completely avoided, allowing the heated catalytic converter to be operated in a consumption-optimized manner.

[0015] In some embodiments of the invention, the turbocharger further comprises a first overflow channel, which has a first end and an opposite second end. The first end is connected to the exhaust gas inlet of the turbine housing and the second end is connected to the gas inlet of the catalytic converter housing. This supplies the heated catalytic converter with exhaust gas, which on the one hand introduces thermal energy into the heated catalytic converter in order to enable or promote the conversion of the fuel in the catalytic converter, and on the other hand vaporizes the fuel, i.e. converts it from a liquid state to a gaseous state. Furthermore, the exhaust gas is used as an oxidizer for oxidizing at least a part of the fuel and releasing heat. Oxygen-rich exhaust gases are particularly suitable for this purpose and are generated, for example, during lean operation of spark-ignition internal combustion engines (air number λ>1) or generally in the case of self-igniting internal combustion engines.

[0016] In some embodiments of the invention, the turbocharger comprises at least one second overflow channel, the second overflow channel having a first end and an opposite second end. The first end is connected to the fresh air outlet of the compressor housing, and the second end is connected to the gas inlet of the catalytic converter housing. In this way, the second overflow channel is used to supply fresh air to the heated catalytic converter. As well as the exhaust gas, the compressed fresh air is also used to add additional thermal energy to the heated catalytic converter. Furthermore, the fresh air is suitable as an oxidizer for the fuel supplied to the heated catalytic converter. In this way, the oxidation is carried out regardless of the composition of the raw exhaust gas, so that the oxidation of the fuel is ensured regardless of the operating state of the internal combustion engine.

[0017] In some embodiments of the invention, the turbocharger comprises a third overflow channel, the third overflow channel having a first end and an opposite second end. The first end is connected to a gas outlet of the catalytic converter housing and the second end is connected to an exhaust gas outlet of the turbine housing. The third overflow channel is thus suitable and intended for supplying a product gas generated in a heated catalytic converter downstream of the exhaust gas turbine to the exhaust pipe. As already mentioned above, the product gas may be or may include a fuel vapor. In other embodiments of the invention, the product gas may be or may include a synthesis gas obtained by reacting a fuel on the heated catalytic converter. In yet other embodiments of the invention, the product gas may be or may include a hot gas obtained by oxidizing a fuel on the heated catalytic converter. In this way, the heated catalytic converter is supplied with exhaust gas or fresh air at a relatively high pressure level upstream of the exhaust gas turbine, and the heated catalytic converter's product gas is supplied at a lower pressure downstream of the exhaust gas turbine, so that the pressure drop within the exhaust gas turbine necessarily causes the exhaust gas or fresh air to flow through the heated catalytic converter.

[0018] In all embodiments of the present invention, the first, second or third overflow channel may not necessarily be present, in some embodiments of the present invention there may be only one or only two overflow channels.

[0019] In some embodiments of the invention, the first overflow channel and / or the second overflow channel and / or the third overflow channel are at least partially designed as a bore in the catalytic converter housing or in the compressor housing or in the turbine housing. A bore of this kind is formed by machining or during the primary moulding of the housing. On the one hand, this results in an easy manufacture of the turbocharger according to the invention and a mechanically robust operation, since no wear-prone plastic or rubber hoses and their connections to the housing are required.

[0020] In some embodiments of the invention, at least one nozzle is disposed at the second end of the third overflow channel such that product gases of the heated catalytic converter are introduced into the exhaust gas flow in a predeterminable direction and / or in predeterminable pulses to additionally promote mixing of the product gases with the exhaust gas flow.

[0021] In some embodiments of the invention, a two-way valve is provided in the first overflow channel and / or in the second overflow channel and / or in the third overflow channel. This type of two-way valve controls the flow in the respective overflow channel in an open-loop or closed-loop manner under the influence of an electric signal from the control device. As a result, depending on the operating conditions, exhaust gas or fresh air or a mixture of exhaust gas and fresh air can be fed to the heated catalytic converter, or the heated catalytic converter is completely deactivated by closing at least one overflow channel. In some embodiments of the invention, the overflow channel may be used as a wastegate valve by venting an unacceptably high boost pressure through the heated catalytic converter to the exhaust line or by bypassing the exhaust gas through the exhaust gas turbine. An additional wastegate valve is therefore not required.

[0022] In some embodiments of the invention, the turbocharger further comprises a three-way valve having three inlets / outlets connected to a first overflow channel, a second overflow channel and the gas inlet. The position of the three-way valve is used to supply the heated catalytic converter with fresh air, exhaust gas or a mixture of fresh air and exhaust gas, so that the operating conditions of the heated catalytic converter can be adjusted over a wide range using a single valve. Closing the three-way valve stops the operation of the heated catalytic converter, e.g. at full load or near full load operating conditions, the exhaust gas aftertreatment does not require additional heating means.

[0023] In one embodiment of the invention, at least one part of the catalytic converter housing and either the compressor housing or the turbine housing are manufactured in one piece. This type of one-piece manufacturing is done by one-piece molding, in particular in a casting process. In another embodiment of the invention, the housing is manufactured at least partially by a 3D printing process. In this way, at least one part of the catalytic converter housing and at least one part of the compressor housing or at least one part of the turbine housing are joined in one piece, and the heat from the compressor housing or the turbine housing is introduced into the heated catalytic converter with almost no waste. In this way, raw (unprocessed) contact surfaces and / or contact surfaces that are oxidized after long-term operation and have a significantly higher heat input resistance can be avoided.

[0024] In some embodiments of the invention, at least one part of the catalytic converter housing, at least one part of the compressor housing and at least one part of the turbine housing can be manufactured in one piece, so that the entire turbocharger is designed to be mechanically robust and compact.

[0025] In some embodiments of the invention, a heat flow of between about 0.5 kW and about 6 kW is introduced into the heated catalytic converter by thermal contact between the catalytic converter housing on the one hand and the compressor housing or the turbine housing on the other hand. In other embodiments of the invention, the heat flow introduced into the heated catalytic converter by thermal contact is between about 1 kW and about 4 kW. In yet other embodiments of the invention, the heat input is between about 0.5 kW and about 3 kW. The above mentioned heat output makes the vaporization and / or conversion of the fuel in the heated catalytic converter efficient without the need for additional electrical auxiliary energy. The internal combustion engine can therefore be operated in a consumption-optimized manner.

[0026] The invention will now be described in more detail on the basis of the drawings, without limiting the general concept of the invention. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a first diagram of a first embodiment of a turbocharger according to the present invention. [Diagram 2] FIG. 2 is a second view of the first embodiment of the turbocharger according to the present invention. [Diagram 3] FIG. 3 is a third view of the first embodiment of the turbocharger according to the present invention. [Figure 4] FIG. 4 is a first diagram of a second embodiment of a turbocharger according to the present invention. [Diagram 5] FIG. 5 is a second view of the second embodiment of the turbocharger according to the present invention. [Figure 6] FIG. 6 is a block diagram of an internal combustion engine having an exhaust gas aftertreatment device and a turbocharger according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] 1 to 3 show a first embodiment of a turbocharger according to the invention. The turbocharger 1 comprises a compressor structure 2, which is designed to compress fresh air required for combustion in an internal combustion engine. In the illustrated exemplary embodiment, the compressor structure 2 is designed as a radial compressor. The compressor structure 2 has a fresh air inlet 201 designed to take in ambient air at a first pressure. Furthermore, the compressor structure 2 has a fresh air outlet 202 designed to discharge the compressed fresh air at a second pressure. The fresh air outlet 202 is connected to the intake manifold of the internal combustion engine and supplies the internal combustion engine with fresh air at high pressure, which is required for the combustion of fuel in the internal combustion engine.

[0029] An exhaust gas turbine 3 having at least one turbine housing 30 is used to drive the compressor arrangement. The turbine housing 30 has an exhaust gas inlet 301 and an exhaust gas outlet 302. At least one turbine wheel is arranged in the turbine housing 30. In the illustrated exemplary embodiment, the exhaust gas turbine is designed as a radial turbine, i.e. the exhaust gas inlet 301 and the exhaust gas outlet 302 are arranged approximately at right angles to each other.

[0030] In some embodiments of the invention, the turbine housing 30 and the compressor housing 20 are integrally formed, for example, as a single cast piece or by 3D printing. In other embodiments of the invention, the housings may be formed of multiple pieces or may be formed separately and connected together by a threaded connection.

[0031] 1 to 3 show a heated catalytic converter 4. The heated catalytic converter 4 comprises a housing 40, the main shape of which is substantially cylindrical. A gas inlet 401 is provided on the underside of the housing 40, through which exhaust gas and / or fresh air is supplied to the heated catalytic converter 4. Furthermore, the heated catalytic converter 4 has at least one fuel inlet 403. A gaseous or liquid fuel, usually gasoline or diesel, is supplied via the fuel inlet 403. The fuel is completely or partially converted in the above-mentioned manner by the exhaust gas or fresh air supplied via the gas inlet 401. The product gas thus produced in the heated catalytic converter 4 is discharged from the heated catalytic converter 4 via a gas outlet 402.

[0032] 1 to 3 further show a retaining bracket 43. The retaining bracket 43 is made of a heat-conducting material, for example a metal or an alloy. The retaining bracket is designed to mechanically fix the catalytic converter housing 40 of the heated catalytic converter 4. One end of the retaining bracket 43 facing away from the catalytic converter housing 40 is in thermally conductive mechanical contact with the turbine housing 30. During operation of the turbocharger, hot exhaust gases flow through the turbine housing 30. This heats up the turbine housing 30. Part of the heat is dissipated to the surroundings by convection and radiation. However, part of the heat introduced into the turbine housing 30 flows into the heated catalytic converter 4 through the retaining bracket 43 and the partial surface 45 formed between the catalytic converter housing 40 and the retaining bracket 43. For this purpose, the catalytic converter housing 40 may be made at least partially of a heat-conducting material, for example a metal or an alloy. In this way, the heated catalytic converter 4 can be raised to a temperature at which it is possible to convert the fuel with fresh air or exhaust gases without or with a reduced supply of electrical auxiliary energy.

[0033] As can be seen, the catalytic converter housing 40 further comprises a port 41 through which a temperature sensor or an electric heating device can be connected. To achieve a more uniform distribution of fuel within the heated catalytic converter 4, multiple fuel inlets 403 may optionally be provided.

[0034] As further shown in figures 1 and 2, the turbocharger according to the invention comprises a first overflow channel 15 having a first end 151 and a second end 152. The first end 151 is connected to an exhaust gas inlet 301 of the turbine housing 30. In this way, the exhaust gas stream leaving the internal combustion engine at a relatively high pressure, for example between about 3.5 and about 5 bar, is at least partially taken off and fed to the heated catalytic converter 4. For this purpose, the second end 152 of the first overflow channel 15 is connected to a gas inlet 401 of the catalytic converter housing 40. The overflow channel 15 may be provided with an optional two-way valve (not shown), by means of which the amount of exhaust gas fed to the heated catalytic converter 4 is controlled.

[0035] Furthermore, the turbocharger according to the first embodiment of the invention comprises a third overflow channel 35 with a first end 351 and an opposite second end 352. The first end 351 is in this embodiment connected to a gas outlet 402 of the catalytic converter housing 40. The second end 352 opens via a nozzle 353 into the turbine housing 30 downstream of the turbine wheel. Downstream of the turbine wheel, a lower pressure is created on the one hand, since the turbine wheel extracts energy from the exhaust gas flow. In addition, the turbine wheel creates turbulence, so that the product gases generated in the heated catalytic converter 4 are well mixed with the exhaust gas main flow. This pressure difference defines the exhaust gas flow through the heated catalytic converter 4. At the same time, the turbocharger according to the invention has a compact design, which saves installation space and facilitates the retrofitting of existing internal combustion engines.

[0036] 4 and 5 show a second embodiment of the present invention in more detail. The same components of the present invention are given the same reference numerals, so the following description is limited to the essential differences of the present invention.

[0037] As can be seen from Fig. 4, in the second exemplary embodiment, the retaining bracket 43 for mechanically and thermally connecting the turbine housing 30 and the catalytic converter housing 40 is omitted. According to the second exemplary embodiment, the catalytic converter housing 40 is made up of two parts, namely an upper part 421 and a lower part 422. In the illustrated exemplary embodiment, the lower part 422 of the catalytic converter housing 40 is formed integrally with the turbine housing 30, i.e. during the primary forming of the turbine housing 30 by metal casting, the lower part 422 is also produced as a homogeneous component of the turbine housing 30 in the same metal casting step.

[0038] Because the lower portion 422 of the catalytic converter housing 40 and the turbine housing 30 are manufactured integrally or monolithically, there is no interface at the part surface 45 and the two parts are thermally bonded to prevent heat input due to irregularities, contamination or oxidation. Thus, the heat input from the turbine housing 30 to the catalytic converter housing 40 is more uniform and / or more effective. In other embodiments of the present invention, such an integral bonded connection between at least one portion of the catalytic converter housing and the turbine housing may be made by soldering, welding or 3D printing.

[0039] In the case of monolithic production according to the second embodiment of the invention, the overflow channels 15, 25 and 35 are simply produced by recesses or bores in the housing. Furthermore, two-way or three-way valves may be integrated into the housing, influencing the supply of exhaust gas or fresh air on the one hand and the removal of product gases on the other hand, in order to adapt the operating parameters of the heated catalytic converter 4 to predeterminable target conditions.

[0040] Figure 6 is a block diagram of an internal combustion engine 7 having an exhaust gas aftertreatment device 72, 73, 74 and a turbocharger according to the present invention. For the sake of clarity, the compressor structure 2, the exhaust gas turbine 3 and the heated catalytic converter 4 are spatially separated in Figure 6. The skilled person is of course aware that these components of the present invention cooperate as described above with reference to Figures 1 to 5.

[0041] The internal combustion engine 7 may be a self-ignited or spark-ignited internal combustion engine. The internal combustion engine 7 is designed to combust fuel with ambient air to provide mechanical power. The internal combustion engine 7 may be used in automobiles, trucks, boats, construction equipment, or stationary in compressors, generators, cogeneration systems, or similar devices.

[0042] During operation, the internal combustion engine 7 is supplied with fresh air or ambient air through the air filter 77. The fresh air is brought to a higher pressure level in the compressor structure 2. For this purpose, the fresh air is supplied to the fresh air inlet 201, compressed by the compressor impeller, and then supplied to the internal combustion engine 7 through the fresh air outlet 202.

[0043] The compressor structure is driven by a rotating shaft 8. The driving force is provided by an exhaust gas turbine 3. To this end, exhaust gases from the internal combustion engine 7 are fed to the exhaust gas turbine 3 via an exhaust gas inlet 301. The exhaust gases are then discharged from the exhaust gas turbine 3 via an exhaust gas outlet 302.

[0044] The exhaust gases are then fed via an exhaust pipe 71 to an exhaust gas aftertreatment device, which reduces soot particles and gaseous pollutants. In the illustrated exemplary embodiment, the exhaust gas aftertreatment device comprises an oxidation catalytic converter 72 designed to oxidize hydrocarbons and carbon monoxide. The exhaust gases thus pretreated reach a particulate filter 73, which retains particulate dust. The exhaust gases are then fed to an SCR catalytic converter 74, where urea is added to reduce nitrogen oxides. The exhaust gas temperature is measured at different points by means of various temperature sensors TIA, which control the heated catalytic converter 4 and the internal combustion engine 7 in an open-loop or closed-loop manner.

[0045] The oxidation catalytic converter 72 and the SCR catalytic converter 74 require high temperatures, for example above 250° C., to operate. The particulate filter 73 also works at low temperatures, but must be operated at high temperatures from time to time in order to oxidize the embedded particles and regenerate the particulate filter. It is therefore necessary to bring the exhaust gases flowing in the exhaust pipe 71 to a predeterminable temperature or to keep them at a high temperature. According to the prior art, this can be achieved by suitable operating conditions of the internal combustion engine 7, for example late or after injection. However, this leads to a deterioration in the exhaust gas behavior and an increase in the fuel requirement of the internal combustion engine 7.

[0046] The invention therefore proposes to use a heated catalytic converter 4 designed to introduce heat into at least one component 72, 73, 74 of an exhaust gas aftertreatment device. For this purpose, fuel is supplied to the heated catalytic converter 4 from a storage tank 74 via an electrically driven pump 46, the fuel flowing into the catalytic converter housing 40 of the heated catalytic converter 4 via a fuel inlet 403. Inside the catalytic converter housing 40 a catalytic converter support coated with catalytic material is arranged.

[0047] In the simplest case, fuel entering through the fuel inlet 403 is vaporized in the heated catalytic converter 4 and leaves the catalytic converter housing 40 via the gas outlet 402. By means of a third overflow channel 35 having a first end 351 and an opposite second end 352, the fuel vapor is introduced into the exhaust pipe 71, where the turbulence generated by the exhaust gas turbine 3 ensures effective mixing. The fuel vapor is then oxidized in the oxidation catalyst 72 and / or in downstream components 73 or 74, releasing heat.

[0048] In other operating conditions, fuel is converted with the exhaust gases and / or fresh air in the heated catalytic converter 4 to produce hot gas or synthesis gas. The synthesis gas is also fed to the exhaust pipe 71 via the third overflow channel 35. The synthesis gas may be converted in the oxidation catalytic converter 72 or downstream components 73, 74, but may have a reduced light-off temperature compared to vaporized but unchemically altered fuel.

[0049] To convert the fuel with exhaust gas or fresh air, the heated catalytic converter 4 is provided with a gas inlet 401. The gas inlet 401 is connected to the first overflow channel 15 and the second overflow channel 25 via the three-way valve 53. The first overflow channel 15 is connected to the gas inlet 301 of the exhaust gas turbine 3 via a first end 151 and extracts the exhaust gas at a relatively high pressure level and supplies it to a port of the three-way valve 53. Furthermore, the illustrated embodiment includes a second overflow channel 25, the first end 251 of which is connected to the fresh air outlet 202 of the compressor structure 2. The opposite second end 252 is connected to a further port of the three-way valve 53. Depending on the position of the three-way valve 53, fresh air or exhaust gas or both are supplied via the gas inlet 401 into the catalytic converter housing 40 of the heated catalytic converter 4. Thus, the oxygen content in the heated catalytic converter 4 is adjusted by the position of the three-way valve 53, which influences the type of conversion of the supplied fuel.

[0050] Both the conversion and the simple vaporization of the fuel in the heated catalytic converter 4 require thermal energy, which on the one hand is generated by at least partial oxidation of the fuel in the heated catalytic converter 4. Furthermore, this energy may be implemented according to the invention by thermally coupling the heated catalytic converter 4 to the exhaust gas turbine 3 and / or the compressor structure 2.

[0051] An electronic open-loop or closed-loop control device 76 may be utilized to drive the amount of fuel delivered, the three-way valve 53 and, if necessary, further components of the heated catalytic converter 4. This device is optionally connected to the engine control unit 75 via a data bus and takes into account the operating conditions of the internal combustion engine 7 when driving the heated catalytic converter 4.

[0052] If the heated catalytic converter 4 is fully integrated into the exhaust gas turbocharger, additional components can be saved. In the illustrated exemplary embodiment, instead of a wastegate valve, a three-way valve 53 is used. For this purpose, if the pressure at the fresh air outlet 202 rises above the permissible amount, the fuel supply to the heated catalytic converter 4 is interrupted and the three-way valve 53 is opened to allow the exhaust gases to flow through the heated catalytic converter 4 from the high pressure side to the low pressure side of the exhaust gas turbine 3.

[0053] Of course, the present invention is not limited to the illustrated embodiments. The above description should therefore be considered as illustrative rather than restrictive. The following claims should be understood as though the described features are present in at least one embodiment of the present invention. This does not exclude the presence of further features. Where a "first" and a "second" embodiment are defined in the claims and in the above description, this designation is used to distinguish between two similar embodiments, rather than to determine an ordering.

Claims

1. A turbocharger (1), comprising: A compressor structure (2) configured to compress fresh air flowing into an internal combustion engine; At least one exhaust gas turbine (3) configured to drive the compressor structure (2); A heated catalytic converter (4) configured to at least partially convert supplied fuel with fresh air and / or exhaust gas, the heated catalytic converter (4) comprising a catalytic converter housing (40) having a gas inlet (401), a gas outlet (402) and a fuel inlet (403); A third overflow channel (35) having a first end (351) and an opposite second end (352); And comprising: The compressor structure (2) comprises at least one compressor housing (20) having a fresh air inlet (201) and a fresh air outlet (202), and at least one compressor impeller disposed within the compressor housing (20); The at least one exhaust gas turbine (3) comprises at least one turbine housing (30) having an exhaust gas inlet (301) and an exhaust gas outlet (302), and at least one turbine wheel disposed within the turbine housing (30); The first end (351) of the third overflow channel (35) is connected to the gas outlet (402) of the catalytic converter housing (40), the second end (352) of the third overflow channel (35) is connected to the exhaust gas outlet (302) of the at least one turbine housing (30), the product gas generated by the heated catalytic converter (4) bypasses the exhaust gas turbine (3) and is sent via the third overflow channel (35) to an exhaust pipe (71) downstream of the exhaust gas turbine (3); The catalytic converter housing (40) and the compressor housing (20) are in thermal contact at at least one partial surface (45); The catalytic converter housing (40) and the turbine housing (30) are in thermal contact at at least one partial surface (45), a turbocharger characterized by this.

2. Further comprising a first overflow channel (15). The first overflow channel (15) has a first end (151) and an opposite second end (152). The first end (151) is connected to the exhaust gas inlet (301) of the turbine housing (30), and the second end (152) is connected to the gas inlet (401) of the catalytic converter housing (40). The turbocharger according to claim 1, characterized in that.

3. Further comprising a second overflow channel (25). The second overflow channel (25) has a first end (251) and an opposite second end (252). The first end (251) is connected to the fresh air outlet (202) of the compressor housing (20), and the second end (252) is connected to the gas inlet (401) of the catalytic converter housing (40). The turbocharger according to claim 2, characterized in that.

4. Further comprising a three-way valve (53) having three inlets / outlets. The first overflow channel (15), the second overflow channel (25), and the gas inlet (401) are connected to the three-way valve (53). The turbocharger according to claim 3, characterized in that.

5. At least one nozzle (353) is disposed at the second end (352) of the third overflow channel (35). The turbocharger according to claim 1, characterized in that.

6. The first overflow channel (15) and / or the second overflow channel (25) and / or the third overflow channel (35) are designed as bores in the catalytic converter housing (40) and / or the compressor housing (20) and / or the turbine housing (30) at least in a predetermined region. The turbocharger according to claim 1, characterized in that.

7. A two-way valve (52) is provided in the first overflow channel (15) and / or the second overflow channel (25) and / or the third overflow channel (35). The turbocharger according to claim 1, characterized in that.

8. At least one part (422) of the catalyst converter housing (40), the compressor housing (20) and the turbine housing (30) are integrally formed so as to have a monolithic structure, The turbocharger according to claim 1, characterized in that.

9. The first overflow channel (15) and / or the second overflow channel (25) and / or the third overflow channel (35) are at least in a predetermined region, the catalyst converter housing (40) and / or the compressor housing (20) and / or the turbine housing (30) are designed as bores in, The turbocharger according to claim 8, characterized in that.

10. At least one part (421, 422) of the catalyst converter housing (40) and the compressor housing (20) or the turbine housing (30) are integrally formed so as to have a monolithic structure, The turbocharger according to claim 1, characterized in that.

11. The catalyst converter housing (40) and at least the compressor housing (20) or the turbine housing (30) are formed as one casting part, The turbocharger according to claim 10, characterized in that.

12. At least one part (422) of the catalyst converter housing (40), the compressor housing (20) and the turbine housing (30) are integrally formed so as to have a monolithic structure, The turbocharger according to claim 1, characterized in that.

13. At least one part (421, 422) of the catalyst converter housing (40) and the compressor housing (20) or the turbine housing (30) are integrally formed so as to have a monolithic structure, The turbocharger according to claim 1, characterized in that.

14. The catalyst converter housing (40) and at least the compressor housing (20) or the turbine housing (30) are formed as one casting part, The turbocharger according to claim 13, characterized in that.

15. When the exhaust gas flows through the turbine housing (30), (a) between the catalyst converter housing (40) and the compressor housing (20), and / or (b) between the catalyst converter housing (40) and the turbine housing (30), wherein a heat flow of about 0.5 kW to about 6 kW is introduced into the catalyst converter housing (40) by thermal contact therebetween. The turbocharger according to claim 1.

16. A method for modifying an internal combustion engine equipped with a turbocharger, comprising: removing an existing turbocharger; installing the turbocharger according to claim 1; A method characterized by including the above steps.

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