DE202006013247U1 - Abgasverwirbler - Google Patents

Abstract

exhaust system (100) for an internal combustion engine having an outer housing (10) into which a hot exhaust gas (31) is introduced through an exhaust gas inlet and from an exhaust gas outlet (12) is discharged, wherein the exhaust gas outlet (12) tubular, in particular with a circular or oval cross-section, is configured, thereby characterized in that in the region of the tubular exhaust gas outlet (12) a Abflussverwirbler (20) is arranged, the at least one vane (23), whereby the exhaust gas (31) deflected in the exhaust gas outlet (12) becomes.

Description

The The present invention relates to an exhaust system for a Internal combustion engine with an outer housing, in which one hot Exhaust gas is introduced through an exhaust gas inlet. Such an exhaust system can for a four-stroke or a two-stroke petrol engine can be used. Since the exhaust system itself has a particularly compact design, it can also be used on hand-operated machines, such as petrol engine driven Cutters, Chainsaws, Hedge trimmers or the like can be used. After a treatment of the exhaust gas within the exhaust system, the exhaust gas from the exhaust outlet discharged into the environment. In the treatment of the exhaust gas can it is a measure for soundproofing the exhaust noise, for pollutant reduction of the exhaust gas or for cooling the Exhaust gases or the like act. Thus, the exhaust gas through the Exhaust system prepared to then pass through the exhaust outlet to lead the environment. The exhaust outlet is designed tubular, in particular with a circular or oval cross-section.

Out It is well known in the art to have exhaust swirlers within to arrange an exhaust system. These exhaust swirlers are used usually, glowing To delete particles in the combustion exhaust gas so that they do not pass through the exhaust outlet are discharged to the environment. For example DE-PS 948 210 discloses an exhaust system with a so-called Cyclone winding or arrangement. It is by the cyclone arrangement ensures that the exhaust gases get a fast rotational movement, whereby the glowing in the exhaust Particles squeezed against the inside of the exhaust system and thereby quickly and safely deleted become. However, this cyclone arrangement is within the exhaust system, ie provided far in front of the exhaust outlet, hence the glowing particles still can come to extinction on the inner wall of the exhaust system.

Further It is known from the prior art that a long exhaust duct For example, behind an exhaust element is arranged to the hot, converted Cool exhaust gases. The exhaust duct itself can also serve as a spark extinguisher, in which he takes a zigzag or arcuate course. In the rule then become the hot ones Exhaust gases from the exhaust duct directly into the open or into the environment. However, very high exhaust gas temperatures still occur directly behind the exhaust outlet.

There the aforementioned Problem especially with very compact exhaust systems occurs in the prior art also in addition Slits or breakthroughs in the outer casing of the Exhaust system arranged, whereby fresh air penetrate into the exhaust system can and by the suction of the hot Combustion exhaust gases are directed back into the environment. By the much cooler Fresh air finds a mixing of the hot exhaust gases with the cool ambient air already held inside the exhaust system. Injectors are also known which also for a cooling of the hot Exhaust gases at the exhaust outlet serve, but because of the pulsating flow of the exhaust gas are less effective. Consequently, still very much high temperatures directly after the exhaust outlet in the exhaust stream on. These high temperatures can lead to a risk of injury especially in portable machines with internal combustion engines come. additionally There is also a risk of fire from the hot exhaust gases.

In front It is an object of the present invention to provide a To provide compact exhaust system in a simple way preferably effectively lowers the exhaust gas temperature in the exhaust outlet. It should as possible recourse to previously known constructions of exhaust systems Become a cost effective too solution to achieve.

to solution This object is an exhaust system with the features of the claim 1 proposed.

In the exhaust system according to the invention it is provided that an exhaust swirling device is arranged in the region of the tubular exhaust gas outlet, which has at least one guide vane, whereby the exiting exhaust gas is deflected or swirled in the exhaust gas outlet. The Abgasverwirbler can be provided before or in the exhaust outlet or the Abgasverwirbler itself represents the exhaust outlet. It is further provided by the invention that the Abgasverwirbler has at least one vane, whereby a deflection or turbulence of the exhaust gas takes place with the ambient air. In this way, a possibly laminar flow of the exhaust gas can be converted into a turbulent flow of the exiting exhaust gas, which mixes directly with the cool ambient air behind the exhaust gas outlet. By the use according to the invention of the exhaust swirling device in the region of the exhaust gas outlet, the exhaust gas is set into rapid rotation by the existing guide vanes. The exhaust gas is fanned out due to centripetal force leaving the exhaust outlet strong in the ambient air. Thus, the exhaust gas can be mixed with the ambient air and cooled at a much shorter distance. Consequently, the exhaust swirling device according to the invention does not serve as a spark extinguisher within an exhaust system, as is known from the prior art, but the exhaust swirling device serves exclusively to reduce the exhaust gas temperature behind the exhaust gas outlet. Since the Abgasver Even though wirbler only has a construction depth of a few centimeters in the intended area of application, the required compact design of the exhaust system can be realized. Also, the exhaust swirler can be integrated into existing constructions of an exhaust system. Larger depths are possible if the requirement of the compact Gauweise is not as strong as eg lawn mowers.

Further advantageous embodiments of the exhaust system are in the dependent claims 2 to 24 listed.

Around preferably a cost-effective Construction of the exhaust system to achieve and easy installation the exhaust system, it may be provided that the Abgasverwirbler as an independent one Component is provided in the region of the exhaust outlet. Consequently are no material changes required in the previous production of the known exhaust systems and also the assembly of the exhaust system is through the exhaust swirlers hardly influenced. In this case, the exhaust swirler as an independent component just in addition be used in the proposed exhaust outlet. Here is however, ensure that the exhaust swirler is not blocked by the be called Exhaust gas flow is forced out of the exhaust gas outlet. For this purpose can the exhaust swirler positively and / or non-positively disposed in the exhaust gas outlet become. It is conceivable, the Abgasverwirbler means of a Screw, rivet, welding, Soldering and / or Clamp to secure in the exhaust outlet or over a Secure bayonet lock in the exhaust outlet.

When has appropriate It has also been proven that the exhaust swirler is arranged in a separate housing is. Thus contains the Abgasverwirbler essentially a housing and provided in the housing Insert having the vane. The additional housing can be used to attach the Abgasverwirblers be used in the exhaust outlet, wherein the in Paragraph previously mentioned connection options can be used. Around preferably the flow resistance of the To keep low exhaust gas swirler, it is recommended to use a circular Cross section for the housing the Abgasverwirblers provide. Of course, the present Invention, however, not on a housing with a circular cross-section limited, so that also oval or other cross-sectional areas for Use can come. To ensure that the exhaust gas goes into a turbulent flow, can small projections on the inside of the case be arranged. Also, the inside of the housing via a rough surface feature. In addition, can the exhaust swirler be arranged in the exhaust outlet, that after the exhaust swirl adjoins a short piece of pipe exhaust outlet before the exhaust gas the housing leaves or into the environment. This measure can be used to that ambient air is drawn into the exhaust outlet, which is there mixed with the exiting exhaust gas, and thus the total Exit temperature lowers before the exhaust gas finally the housing of the Exhaust system leaves.

Around preferably the entire cross-sectional area of the housing for the To use exhaust flow, it is recommended to use a medium mounting surface as fixed element to which the vane is mounted centrally could be, small areas embody. In this case, the entire exhaust gas flow through the guide vanes be deflected or swirled to effectively temperature peaks to avoid in the exhaust stream. Optionally, on the mentioned fixed Element in the form of a middle mounting surface can be dispensed to the entire cross-sectional area of the housing for the to use complete exhaust gas flow, in which case the vanes in the middle are not fastened. In this case, the mean cross-sectional area the Abgasverwirblers open designed.

to Achieving a cost-effective Production of Abgasverwirblers, a sheet metal construction can be provided be. It can both the housing as well as the use with the vanes made of sheet metal. These Sheet metal constructions can by a deep drawing or other forming process produced become. In this variant, it is possible the Abgasverwirbler also from the outer housing, in particular a housing shell, the Outlet or reshape the exhaust system. Consequently, on a connection the Abgasverwirblers be dispensed with the exhaust system, since these two Components are made in one piece and of the same material. Also it is conceivable only the case or to mold the use of the exhaust swirler from the outer casing of the exhaust system.

at another embodiment the exhaust system, it is conceivable that the Abgasverwirbler, in particular its use with the vanes, consists of a casting. It is appropriate that it is the casting to a precision casting. Although one is Casting in production more expensive than a comparable sheet metal construction, However, the scope is greater, so z. B. profiled vanes to be poured. Of course can also use the entire Abgasverwirbler so use and housing as one or more castings be designed.

In a particularly interesting embodiment of the Abgasverwirblers, it is provided that for each vane a triangular Öff is provided, is passed through which a part of the exhaust gas and the exhaust gas stream. As a rule, the nth part of the exhaust gas is passed through the nth opening via the nth guide vane. Thus, two, three or more vanes for the exhaust swirler may be present. In this case, the exhaust gas or a part of the exhaust gas first flows along the direction of flow of the guide vanes, and then passed through the triangular opening in the ambient air. Through the use of n vanes, the exhaust stream is fanned out into n-parts.

Also it is conceivable that the guide vanes have circular segment-shaped surfaces, the particular about have a flat or flat surfaces. at The use of n vanes then 360 ° / n arcuate surfaces for the vanes come for use. Also, a vane may be curved, wavy or curved surface feature, especially when this is a short turbine-like or propeller-like blade is designed. Optionally the vanes also in an unequal distribution over the Scope of the exhaust outlet to be arranged, d. H. adjacent vanes can each have different angles to each other.

Around preferably to use the entire cross-section of the exhaust gas swirler for the exhaust gas outlet, it is appropriate that the approximate Width of a vane corresponds to a radius of the Abgasverwirblers. Thus, the flow resistance the Abgasverwirblers be significantly reduced. To this end especially the middle attachment of the vanes, if available, if possible be space-saving or designed small. This attachment surface is usually arranged around the center of the Abgasverwirblers. Likewise, it is recommended that all vanes symmetrically equal to the midpoint or the longitudinal axis to arrange the exhaust swirler. In this way can be a uniform as well effective mixture of the exhaust gas with the ambient air guaranteed become. However, the invention is not on symmetrical vanes limited, so that the individual vanes geometrically different can be configured.

Further it is useful if the area of all openings for one Partial flow of the exhaust gas is at least as large as the cross-sectional area of the Exhaust outlet. Thus, there is no cross-sectional reduction, which increased to an flow resistance leads. The hangs Passage area an opening for one Partial flow of the exhaust gas substantially also from the axial recess the corresponding vane together. Where to find out leaves, the bigger the axial depression of the vane is, the larger the area the passage opening for the respective partial flow of the exhaust gas. Advantageously, the axial Deepening of the vane 5-70% the diameter of the exhaust duct, especially 10-50% and 10-30% quite advantageous 15-30%. By this diameter-height ratio in Exhaust turbulator leaves an optimal flow reach the exhaust gas. When using a two-stroke engine can if necessary, the exhaust swirler can also be used to provide the necessary flow resistance for optimal motor filling to provide. Accordingly, the exhaust swirler, in particular its flow resistance, be adjusted to the internal combustion engine.

to Achieving a comprehensive turbulence of the exhaust gas with the ambient air, it is appropriate that the exhaust swirler is substantially tangential to the exhaust gas Longitudinal axis or unscrews. Since the exhaust also in the direction of the longitudinal axis (ie, axially) is pushed out of the exhaust outlet, thus finds a comprehensive three-dimensional mixing of the exhaust gas with the ambient air instead. Consequently, cool the exhaust gas is already a short distance behind the exhaust outlet significantly, with this distance is a few centimeters. Also it is conceivable that the Abgasverwirbler the exhaust gas substantially radial to the longitudinal axis of the Abgasverwirblers out. The same positive ones occur Effects that have been previously described. To the exhaust as desired from the To divert exhaust swirlers or out of the exhaust outlet, the Geometry of the vanes adapted accordingly. in this connection It is recommended that the fins be similar to Turbine blades to arrange the desired To lend a twist. For this purpose they may be rotationally symmetrical arranged guide vanes has an aircraft propeller over n propeller blades. in this connection can the individual propeller blades aslant to the flow direction of be arranged incoming exhaust gas. Due to the multitude of Design options, can be a desired one Realizing turbulence of the exhaust gas with the ambient air.

Furthermore, the exhaust system according to the invention may expediently be provided with at least one catalyst element for the exhaust gas treatment. By using one or more catalyst elements, aftertreatment of the exhaust gas with the (chemical) components contained in the exhaust gas is made possible. In this case, for example, the existing hydrocarbons using the residual oxygen content to carbon dioxide and water or carbon monoxide implemented. However, since additional heat is released in this chemical conversion process, the already hot exhaust gases are additionally heated up. Thus, it is further appropriate that by the Katalysatorele ment led exhaust gases by means of a downstream exhaust duct already pre-cool within the exhaust system. At the same time, the sparks in the exhaust gas should be extinguished. For this purpose, an additional spark protection screen may be arranged, in particular in front of or in the exhaust swirling device. This spark arrestor fulfills the task of filtering out any sparks that may still be present in the exhaust gas so that they do not escape into the environment. In a particularly simple construction, the spark arrestor screen is arranged directly in front of or behind the guide vanes and can be correspondingly easily replaced for maintenance purposes, provided that the exhaust swirler is arranged by means of a reversibly detachable connection to the exhaust system or in the exhaust gas outlet. Consequently, when disassembling the Abgasverwirblers directly the spark arrestor can be changed or maintained.

at a particularly interesting embodiment of the exhaust system it can be provided that the catalyst element in a catalyst chamber is arranged and the exhaust gases are discharged from the catalyst chamber be passed through an exhaust passage to the exhaust swirler before the exhaust gas passes through the exhaust outlet into the environment. In addition, can between the exhaust passage and the Abgasverwirbler the already described Spark arrestor be used. Such an exhaust system according to the invention not only has a compact design, but also fulfills the legal environmental regulations.

Further the invention is also directed to an exhaust swirler according to the claim 25 directed. This exhaust swirler has the features one of the claims 1 to 24 on.

different embodiments The invention will be described below with reference to the accompanying drawings described in more detail. In a purely schematic representation:

1 3 shows a three-dimensional view of an exhaust system according to the invention with an exhaust swirler having five propeller-like guide surfaces,

2 in a three-dimensional exploded view, a similar exhaust system according to the invention - as in 1 With an exhaust swirler with four vanes,

3 in a perspective view of an exhaust swirler with five propeller-like vanes,

4a , b, c show, in three different three-dimensional views, an insert for an exhaust-gas swirler, which has a total of four planar and circular segment-shaped guide vanes,

5a , B a further insert for a Abgasverwirbler, which also has four planar and circular segment-shaped vanes, but is designed to be open in the central cross-sectional area, and

6a to e e another variant for a Abgasverwirbler in different views, in which the Abgasverwirbler is partially formed from the exhaust system, and

7a to d in various views, an exhaust system with the exhaust swirl from the 6a to 6e ,

In the 1 is an exhaust system according to the invention 100 shown in three-dimensional representation. This shows the exhaust system 100 an exhaust swirler 20 on, in the exhaust outlet 12 is arranged. This exhaust outlet 12 is located in an upper housing shell 11 that with a lower housing shell 11 together the outer casing 10 forms. The two lower and upper housing shells 11 can by a welded joint, a bead or by the illustrated connecting means 19 be connected to each other gas-tight. In the 1 is not shown an exhaust inlet, whereby the exhaust gas flow 31 directly from a cylinder of the internal combustion engine into the exhaust system 100 can get. However, as can be seen, comes a Abgasver weirler 20 used, the total of five propeller-like vanes 23 has, wherein the respective guide surfaces are arranged obliquely to the incoming exhaust gas flow. As a result, the exiting exhaust gas flow 31 lent a twist, causing the exhaust 31 directly behind the exhaust outlet 12 is swirled or mixed with the ambient air. To avoid possible flow losses through the additionally used exhaust swirling device 20 The individual vanes are enough to cause 23 from the center 27 , which is also the longitudinal axis of the Abgasverwirblers 20 forms, to the circular inner surface of the exhaust passage 15 , As a result, the entire cross-sectional area of the exhaust swirler becomes 20 or the exhaust outlet 12 for turbulence of the exhaust gas stream 31 used. As a result, a laminar flow in the exhaust stream 31 is avoided. This is an optimal turbulence of the exhaust gas directly after exiting the exhaust outlet 12 causes.

From the 2 goes another exhaust system according to the invention 100 before, in which also a Abgasverwirbler 20 in the exhaust outlet 12 is provided. This exhaust swirler 20 essentially contains its own housing 21 and one in the housing 21 intended use 22 on which the vanes 23 are arranged. Consequently, the exhaust swirler 20 constructed in two parts. This allows a cost-effective production of Abgasver Spinner 20 to reach. Also the assembly of the exhaust swirler 20 is due to this modular design of the exhaust system 100 simplified. In addition, the exhaust system points 100 a catalyst element (not shown) disposed within a catalyst chamber 13 is arranged. From the catalyst chamber 13 goes an exhaust duct 15 from, which is designed meander-shaped and the Abgasverwirbler 20 ends. Between the exhaust duct 15 and the exhaust swirler 20 In addition, at least one spark protection screen may be arranged. To as simple a design of the catalyst chamber 13 and the exhaust duct 15 to effect are two chamber halves 14 provided the catalyst chamber 13 and at the same time the exhaust duct 15 form. In these two chamber halves 14 it is an upper and lower chamber half 14 , which themselves can consist of sheet metal parts. These two chamber halves 14 be through spacers 17 approximately in the middle of the exhaust system 100 held. Around the upper half of the chamber 14 with the lower chamber half 14 To connect, additional connecting means 19 , Which consist of a nut connection can be provided. It is also conceivable that the two chamber halves 14 be connected by a bead of its edge area. Advantageously, can be when using additional connecting means 19 also the exhaust swirler 20 or his housing 21 with the chamber halves 14 connect. These are in the housing 21 the Abgasverwirblers 20 breakthroughs 30 provided with further breakthroughs 30 in the chamber halves 14 are mounted congruently.

To the use 22 safe in the housing 21 the Abgasverwirblers 20 to install, this can be positive and / or non-positive in the housing 21 be provided. Also, it is conceivable the use 22 between the edge of the exhaust outlet 12 and the swirler housing 21 pinch. In a special variant, even the use 22 rotatable in the housing 21 to be ordered.

Furthermore, in the exhaust system 100 from the 2 below the catalyst chamber 13 a flow plate 16 provided with openings for an exhaust passage. Thus, this flow plate 16 between the lower half of the chamber 14 and the lower housing shell 11 arranged. Also, a flange disc 18 between the flow plate 16 and the lower housing shell 11 to be available.

From the 3 goes an exhaust swirler 20 which is reproduced in three-dimensional representation. In this exhaust swirler 20 is the housing 21 from a sheet metal part. In the case 21 is the use 22 with a total of five propeller-like vanes 23 arranged. These vanes 23 have a circular segment-like contour, wherein the circle segments form approximately an angle of 72 ° (360 ° / 5 = 72 °, since five vanes). The surfaces of the vanes 23 are inclined or tilted to the flow direction of the incoming exhaust gas stream 31 arranged. The width 28 the vanes 23 essentially goes from the middle 27 , which is formed as a fixed element, to the circular or oval edge of the cylinder-like insert 22 , The middle-point 27 or the longitudinal axis 27 is formed by a five-star closed surface, from which the five vanes 23 go out radially or converge. It is also conceivable to use, for example, a pipe or a continuous cylinder instead of the closed, central surface, from the outer edge of the guide vanes 23 go off radially. Also, this central cross-sectional area can be designed open, as will be described below.

Like in the 3 it can be seen, the exhaust gas flow 31 through the side opening 29 into the exhaust swirler 20 initiated. The exhaust gas flow 31 is then through the housing 21 diverted to use on 22 with the vanes 23 hold true. This can be in the housing 21 In addition, at least one spark arrestor be used. This spark arrestor can be placed between the housing 21 and the upper half of the chamber 14 be arranged and attached. Also, the exhaust swirler 20 still a short piece of pipe behind the vanes 23 on, which either by the Abgasverwirbler 20 , especially the use 22 , or through the tubular exhaust outlet 12 can be formed.

In the 4a , b and c is an embodiment of an insert 22 the Abgasverwirblers 20 shown in three-dimensional representation. The individual show 4a , b and c respectively different views of the same three-dimensional use 22 , To clarify the operation of the Abgasverwirblers 20 or the use 22 and the vanes arranged thereon 23 is the exhaust gas flow 31 shown in thick arrows as an example.

The 4a shows the insert 22 essentially from its front 24 , This is the front 24 through the exhaust gas flow 31 incident flow. This exhaust stream 31 now applies to the circular segment-shaped vanes 23 which run obliquely to the rear or axially to the rear. In total there are four vanes 23 in use 22 intended. To ensure the most stable attachment of the guide vanes 23 To reach is a cross as a fixed element in the front 24 intended. On either side of the cross goes one side of the vane 23 from. This page is the width 28 the vane 23 specified. The width 28 corresponds essentially to the radius of the cylindrical insert 22 or of the circular housing 21 , Now the exhaust 31 on the obliquely backward vanes 23 it will be tangential to the longitudinal axis through the planar guide surfaces 27 through triangular openings 26 directed. At the end of the open side of the vane 23 is in each case a triangular opening 26 intended. Consequently, for the four vanes 23 also four triangular openings 26 intended. The triangular opening is on the one hand by the unpaved side of the vane 23 formed on the other hand from one side of the already described, fixed cross on the front 24 and an outgoing substantially orthogonal side of the circular edge of the insert 22 ,

In the 4b is the same use 22 out 4a shown in three-dimensional side view. Here is clearly the circular segment-like guide surface 23 to recognize, which consists in the present case of a 90 ° arc segment (quarter circle). Also is the triangular opening 26 clearly visible, by the one on the vane 23 derived exhaust 31 penetrates, then with the obtained twist from the insert 22 or the exhaust outlet 12 to be able to escape. This swirl of the exhaust stream 31 is exemplified by the two arrows 31 shown. Of course, this exhaust stream can also be generated further radially outward. By the number n of the vanes 23 as well as the design of the individual vanes 23 itself, can have a direct impact on the desired swirl of the exhaust stream 31 be taken.

The present application 22 consists of a sheet metal part, which itself is inexpensive to manufacture. To extend the life of this use 22 To increase, a special alloy for the sheet can be used. Also, a stainless steel sheet can be used. Also, it is conceivable the use 22 provided with a surface coating, whereby the service life or service life of the insert 22 can be extended.

The 4c shows the already known use 22 from the 4a , b. However, this time especially the back 25 of the insert 20 shown. This occurs at the front 24 impinging exhaust gas 31 on the four vanes 23 and through it through the four triangular openings 26 because of the engagement 22 self-directed. Through the four vane 23 becomes the exhaust gas flow 31 divided into a total of four sub-streams. These partial exhaust streams occur tangentially or radially to the longitudinal axis 27 from the triangular openings 26 out. Consequently, the exhaust gas flow 31 through the vane 23 get the desired spin so that he then after his exit from the exhaust outlet 12 can mix directly with the ambient air.

In the 5a , b will be another use 22 for an exhaust swirler 20 shown. This use 22 also has four vanes 23 on. The essential difference to the use 22 from the 4a , b, c is that here the vanes 23 are not attached in the middle cross-sectional area. Consequently, the average cross-sectional area is around the midpoint 27 or the longitudinal axis 27 designed open, since it has been dispensed with a fixed element. Thus, the entire cross-sectional area is for a flow of the exhaust gas 31 open. However, this makes the outer part of the exhaust gas 31 stronger from the vanes 23 diverted as the inner part of the exhaust gas 31 which more or less unaffected the (cruciform) opening 26 the Abgasverwirblers 20 can happen. Depending on the flow velocity of the exhaust gas 31 Nevertheless, a turbulence of the inner part of the exhaust gas 31 take place as this part through the outer part of the exhaust gas 31 can be carried away. This is an indirect deflection or turbulence of the inner part.

Like from the 5a that the use 22 essentially from its front 24 is apparent, the use is 22 on his front 24 from the exhaust 31 flowed, so the exhaust 31 then mixed and / or swirled at the back 25 out of action 22 flows.

In contrast to 5a is in the 5b the use 22 essentially from its back 25 shown. This is particularly clear, the short pipe section of the insert 22 behind the vanes 23 recognizable. This short piece of pipe has in the present case a circular cross-section. The individual vanes 23 are only on the circular outer wall of the insert 22 attached. Clearly visible is the cross-shaped opening 26 in the middle cross-sectional area of the insert 22 , In addition, it is visible how the exiting exhaust 31 initially in the short tube section of the insert 22 is led before it finally the exhaust outlet 12 can leave to get into the ambient air.

Partially can - depending on the flow velocity of the exhaust stream 31 - a pull in the area of the center 27 form, reducing the ambient air outside the exhaust system 100 in the center of the exhaust outlet 12 or the use 22 is sucked into it. Thus, there is already a mixing of the exiting exhaust gases within the exhaust outlet 12 , To further enforce this suction, it is advisable to deflect the deflected or discharged exhaust gas streams 31 within a short piece of pipe to guide, thus, the suction effect, which is in the area of the center 27 is strengthened.

The illustrated missions 22 from the 4a , b, c as well 5a , b can - as already mentioned - be designed as a sheet metal part. However, the use can 22 also be designed as a casting, in particular a precision casting. This casting can also be surface-coated. Of course, it is also conceivable that the Abgasverwirbler 20 in one piece from a housing 21 and a mission 22 with the appropriate vanes 23 can be designed so that the housing 21 and the use 22 form a part or a piece and in particular are made of the same material.

In the 6a to e is another Abgasverwirbler 20 shown where the case 21 and the use 22 are designed in one piece. The special feature of this exhaust swirler 20 lies in the fact that the Abgasverwirbler 20 wholly or partly from a housing shell 11 or the outer housing 10 the exhaust system 100 can be formed. To get a particularly inexpensive and simple construction, another essay can 11a in the area of the exhaust outlet 12 be used. This essay sheet can 11a be attached to the outer housing via welding, riveting, screwing or soldering connections. In this variant, it is conceivable that already described spark arrestor between the vanes 23 and the additional attachment plate 11a to arrange. Of course, the spark arrestor also before the vanes 23 be arrangeable.

In the 6a is a front view of one of the outer housing 10 molded exhaust swirlers 20 shown. Here are through the exhaust outlet 12 the vanes 23 the Abgasverwirblers 20 to recognize. These vanes 23 are from the outer casing 10 formed by a thermoforming or other molding process. This forming step for the Abgasverwirbler 20 can directly when forming the outer casing 10 to the housing shell 11 respectively. Thus, no additional manufacturing step is required, whereby a significant cost savings is possible. Furthermore, in this forming step by the axial recess of the guide vanes 23 also the diameter-height ratio in the exhaust swirler 20 be determined.

In the 6b is the section II through the 6a shown. Here it becomes clear that the housing 21 the Abgasverwirblers 20 used in one piece 22 the Abgasverwirblers is configured. Both the case 21 as well as the use 22 are doing through the outer case 10 educated. The advantage of this variant is that fewer components and thus fewer sealing points are available. It should be noted, however, that the exhaust swirler 20 from the 6a until e can also consist of additional sheet metal parts in the area of the exhaust outlet 12 on the outer casing 10 be attached.

In the 6c is a rear view of the Abgasverwirbler 20 from the 6a and b shown. It can be clearly seen that the four vanes 23 segment-like from the outer housing 10 have been formed. However, this forming process is a star-shaped center 27 stopped. Of course, it is also conceivable when forming on this star-shaped center 27 to renounce.

In the 6d and 6e is a three-dimensional view of the Abgasverwirblers 20 shown. In both figures is the triangular opening 26 after the vanes 23 to recognize. In the present variant of the Abgasverwirblers 20 is the area of all openings 26 for a partial flow of the exhaust gas 31 smaller than the cross-sectional area of the exhaust outlet 12 , Thus, there is a cross-sectional reduction in the exhaust swirling. Unless the fins 23 deeper, ie with a larger axial recess from the outer housing 10 can be formed, the total area of all openings 26 enlarge.

In the 7a to d is another variant of the exhaust system 100 with an exhaust swirler 20 from the 6a to e shown in different views.

The 7a and 7b show a three-dimensional view of the outside of the exhaust system 100 , It can be clearly seen that the Abgasverwirbler 20 partly from the outer housing 10 , in particular the housing shell 11 , has been formed. Additionally comes in the area of the exhaust outlet 12 an essay sheet 11a used, creating the actual tubular exhaust outlet 12 is formed.

In the 7c is a section II-II through the 7b shown. From this sectional drawing it is clear that the Abgasverwirbler 20 from the case half 11 has been formed. Furthermore, the additional top plate 11a to recognize.

In the 7d is a schematic exploded view of the outer parts of the exhaust system 100 shown. Also in this view it becomes clear that the exhaust swirler 20 with its vanes 23 and the associated openings 26 from the case half 11 has been formed. It also becomes clear that between the vanes 23 and the separate attachment plate 11a a spark arrestor can be arranged. This spark arrest screen could then by attaching the attachment plate 11a be kept up.

Finally, it should be mentioned that the technical features described above individually or in any combination for the exhaust system according to the invention 100 or the Abgasverwirbler 20 can be used unless explicitly mutually exclusive.

100

exhaust system

10

outer casing

11

shell

11a

essay

12

Exhaust outlet in 11

13

catalyst chamber

14

chamber half

15

exhaust duct

16

flow sheet (with openings)

17

spacer

18

flange

19

connecting means

20

Abgasverwirbler

21

Housing of 20

22

Use of 20

23

vane

24

Front of 22

25

Back of 22

26

Opening for exhaust gas flow

27

Midpoint / longitudinal axis of 20 respectively. 22

28

Width of 23

29

Inlet opening for exhaust gas flow

30

breakthrough for connecting means

31

arrow for exhaust gas flow

Claims (25)

Exhaust system ( 100 ) for an internal combustion engine with an outer housing ( 10 ) into which a hot exhaust gas ( 31 ) is introduced through an exhaust gas inlet and from an exhaust gas outlet ( 12 ), wherein the exhaust outlet ( 12 ) is tubular, in particular with a circular or oval cross-section, is designed, characterized in that in the region of the tubular exhaust gas outlet ( 12 ) an exhaust swirler ( 20 ) is arranged, the at least one vane ( 23 ), whereby the exhaust gas ( 31 ) in the exhaust outlet ( 12 ) is distracted. Exhaust system according to claim 1, characterized in that the exhaust swirler ( 20 ) as an independent component in the region of the exhaust gas outlet ( 12 ) is provided. Exhaust system according to claim 1 or 2, characterized in that the Abgasverwirbler ( 20 ) in a separate housing ( 21 ) is arranged, in particular in a housing ( 21 ) with a section-wise, circular or oval cross section, wherein the housing ( 21 ) in particular for fastening the exhaust swirling device ( 20 ) in the region of the tubular exhaust gas outlet ( 12 ) serves. Exhaust system according to one of the preceding claims, characterized in that the Abgasverwirbler ( 20 ) in the exhaust outlet ( 12 ) is arranged, that after the exhaust swirler ( 20 ) still a short piece of pipe, in particular the exhaust gas outlet ( 12 ), before the exhaust gas ( 31 ) the housing ( 10 ) leaves. Exhaust system according to one of the preceding claims, characterized in that the Abgasverwirbler ( 20 ) has a sheet metal construction, wherein in particular a part or the entire exhaust swirl ( 20 ) from the outer housing ( 10 ) is shapeable. Exhaust system according to one of claims 1 to 4, characterized in that the Abgasverwirbler ( 20 ), a casting, in particular a precision casting, having. Exhaust system according to one of the preceding claims, characterized in that the entire exhaust gas ( 31 ) by means of the vane (s) ( 23 ) is deflectable, whereby a swirling of the entire exhaust gas ( 31 ) takes place with the ambient air. Exhaust system according to claim 7, characterized in that in the middle cross-sectional area of the exhaust swirling device ( 20 ) a fixed element is provided, on which also the vane (s) ( 23 ) are fastened. Exhaust system according to one of claims 1 to 6, characterized in that only a part of the exhaust gas ( 31 ) by means of the vane (s) ( 23 ) is deflectable, wherein an outer part of the exhaust gas ( 31 ) through the vane (s) ( 23 ) is influenced, while an inner part in the middle cross-sectional area uninfluenced the exhaust swirl ( 20 ) happens. Exhaust system according to claim 9, characterized in that the average cross-sectional area of the exhaust swirling device ( 20 ) is designed open. Exhaust system according to one of the preceding claims, characterized in that to each vane ( 23 ) a triangular opening ( 26 ) is provided, through which a part of the exhaust gas ( 31 ). Exhaust system according to claim 11, characterized in that the exhaust gas ( 31 ) in the flow direction first the vane (s) ( 23 ) and then through the triangular openings ( 26 ge is headed. Exhaust system according to one of the preceding claims, characterized in that a guide vane ( 23 ) has a circular-segment-shaped surface which is designed in particular planar. Exhaust system according to one of the preceding claims, characterized in that a guide vane ( 23 ) is designed arcuate or wave-like. Exhaust system according to one of the preceding claims, characterized in that the approximate width ( 28 ) a vane ( 23 ) a radius of the Abgasverwirblers ( 20 ) corresponds. Exhaust system according to one of the preceding claims, characterized in that all guide vanes ( 23 ) which are constructed symmetrically the same. Exhaust system according to one of the preceding claims, characterized in that the Abgasverwirbler ( 20 ) the exhaust gas ( 31 ) substantially tangential to the longitudinal axis ( 27 ) of the exhaust swirling device ( 20 ). Exhaust system according to one of claims 1 to 16, characterized in that the Abgasverwirbler ( 20 ) the exhaust gas ( 31 ) substantially radially to the longitudinal axis ( 27 ) of the exhaust swirling device ( 20 ). Exhaust system according to one of the preceding claims, characterized in that the hot exhaust gas ( 31 ) after treatment of the exhaust gas ( 31 ) from the exhaust outlet ( 12 ) is discharged. Exhaust system according to one of the preceding claims, characterized characterized in that at least one catalyst element for the exhaust gas treatment is arranged in the exhaust system. Exhaust system according to claim 20, characterized in that the catalyst element in a catalyst chamber ( 13 ) and the exhaust gases ( 31 ) from the catalyst chamber ( 13 ) through an exhaust duct ( 15 ) to the exhaust swirler ( 20 ) before the exhaust gas ( 31 ) through the exhaust outlet ( 12 ) enters the environment. Exhaust system according to one of the preceding claims, characterized in that at least one spark arrestor before or in the exhaust swirl ( 20 ) is arranged. Exhaust system according to one of the preceding claims, characterized in that the axial recess of the guide vanes ( 23 ) 5 to 70% of the diameter of the exhaust gas duct ( 12 ), advantageously 10 to 50% and particularly advantageously 15 to 30%. Exhaust system according to one of the preceding claims, characterized in that the surface of all openings ( 26 ) for a partial flow of the exhaust gas ( 31 ) is at least as large as the cross-sectional area of the exhaust gas outlet ( 12 ). Exhaust swirler ( 20 ) with the features of one of the preceding claims for an exhaust system.