DE3929205A1 - EXHAUST APPARATUS, IN PARTICULAR. EXHAUST GAS PURIFICATION DEVICE - Google Patents

Description

The invention relates to an exhaust device a double-shell housing, the inner shell at least in sections via an elastic bearing mat, in particular mineral fiber mat is stored in the outer shell, in particular an exhaust gas purification device with a two half-shells existing outer housing, in which over an elastic storage mat, especially a so-called Swelling mat, at least one with a honeycomb structure Carrier body as well as inner and input side Shielding funnels and, if necessary, shielding rings between successive carrier bodies are stored.

In such exhaust devices with a double-shell housing there is basically the problem of balancing the thermal expansion differences between the inner Shell and the outer shell, because of the thermal Shielding by the mineral fiber mat during operation shows significant temperature differences. Usually one goes to intercept thermal expansion Assume that you are at least on any one Installed a sliding seat. This results in the miss Liche situation that you have two different thermal Expansion differences must take into account, namely sometimes radial expansion differences between the inner shell and Outer shell and on the other axial differences in elongation between the inner lining funnel and example as the adjoining mostly ceramic support body. Even if you also divide this ra attempted to compensate for differences in elongation, so it did it has been shown in practice that the overlapping areas, in which the strain shift should take place at the high operating temperatures often so closely together  stick that in reality a functioning slide itz does not come about and therefore the lining funnel and other spacer rings make correct folds, which leads to considerable tension and a great risk of breakage the ceramic monolith leads. But also with Exhaust devices without built-in mineral Carrier body, such as in isolated dop Pelvic shell elbow is the problem of catching the deh differences in the gas-carrying inner manifold shells compared to the load-bearing outer manifold shells in the same Way relevant.

The invention is therefore based on the object of an exhaust gas to design the device of the type mentioned at the beginning, that with a simple structure the problems with axial and ra dialing differences in elongation, and at a favorable price Transition to any ceramic parts without the appearance of voltage spikes and the risk of wrinkles can be solved.

To achieve this object, the invention provides that the shielding funnels and rings from a close-knit sliding elastic wire mesh mat formed and both ends are fixed.

The configuration according to the invention can be used in egg solve a number of special problems. To the one such wire mesh mat - suitable are preferably mesh fabrics with a mesh size <0.5 mm - very easy to process in press or deep-drawing molds bite, so that even very complicated shell structures can be done. On the other hand there are such shields parts from a wire mesh mat, both lengthways as well as radially and transversely, with a very large one  Provide elasticity, so that the aforementioned Differences in elongation both in the axial direction and in radial direction can be easily caught in the wire mesh can.

In a preferred embodiment of an inventive Exhaust gas purification device in such a way that the in the connecting line zen jammed or welded shielding funnels engages around the front end of the carrier body, where in the case of any shielding rings, the be to grasp adjacent carrier body ends by clamping, he there is also a compensation for the expansion tolerance absolute certainty against that by any difference too strong stress peaks occur, which lead to the destruction of the thin-walled ceramic could.

The special properties of a wire mesh mat prevent any risk of wrinkles can also be seen at different strains, for example, the one from egg ner funnel-made wire mesh mat and the clamped-around ceramic door body. As extensive tests have shown disrupts the porosity of a shielding funnel from one Wire mesh mat compared to the dense formation of one Sheet metal deep-drawn shielding funnel in no way because with a sufficiently small mesh size, on the one hand, still sufficient elasticity of the fabricated from it neren shielding component is guaranteed and on the other due to the mesh opening occurring, no damage Mineral fiber mat can take place, which yes in the Practice is more heat-resistant than metal anyway, others but also blowing out or falling out  reliably prevented from parts made of the mineral fiber mat can be.

Further advantages, features and details of the invention result from the following description of an off management example and based on the drawing. Show:

Fig. 1 shows a longitudinal section through an inventively formed exhaust gas purification device,

Fig. 2 shows a section along the line II-II in Fig. 1,

Fig. 3 shows a longitudinal section through an insulated double shell manifold with ge formed from a wire mesh mat inner housing and

FIG. 4 shows a cross section along the line IV-IV in FIG. 3.

The exhaust gas cleaning device shown in FIGS . 1 and 2 comprises, in a manner known per se, a two-shell outer housing 1 , the two half shells 1 a and 1 b of which are welded to one another at their flanges 2 and 3 in the parting plane. In the outer housing 1 are shown in the exemplary embodiment ge two honeycomb structured ceramic carrier bodies 4 and 4 'with the help of a continuous over the entire length of the exhaust gas cleaning device mineral fiber mat 5 , which are spaced apart in the middle. The input cone 6 and the output cone not shown ge covering known per se inner shielding funnel 7 consists according to the invention of a wire mesh mat, which is attached to the connection piece both on the input side in the - which is achieved in the present case by jamming - and on the ge opposite side is fixed. For this purpose, in the exemplary embodiment shown, the shielding funnel 7 consisting of a wire mesh mat is stretched elastically on the end of the carrier body 4 , an additional holding effect also being provided by the pressure of the surrounding mineral fiber mat 5 . In the same manner, the shielding ring 10 for the gap 11 between the adjacent carrier bodies 4 and 4 'is made of a wire mesh mat and stretched onto the ends of the carrier body. With this design, the inner shielding cylinder can not only be very easily put around complicated inner structures, as must be the case with the complex-shaped carrier body 4 ( FIG. 2), but it can neither occur thermally caused voltage peaks nor discard or From the shielding funnels or shielding rings, neither in the radial nor in the axial direction. It goes without saying that before the outer shells 1 a and 1 b are applied, the shielding funnel 7 placed around the carrier body 4 does not initially lie completely into the upper depression 8 , at least not when it is tensioned onto the carrier body 4 becomes. When the two shell halves 1 a and 1 b of the outer housing are pressed together, any lifting off at this point is corrected again.

In FIGS. 3 and 4 is illustrated with reference to an isolated double saddle lenkrümmers with a metallic outer housing 1 'and ei nem inner casing 9, like the inventive construction of the inner casing can be used from a wire mesh mat in a very simple and effective form in other types of gas devices to can avoid the otherwise usual complicated sliding seats in the loading area of the inner housing and / or outer housing. Also there, as usual, a mineral fiber mat 5 'between the outer housing 1 ' and the mat made of wire mesh inner housing 9 is provided, due to the complicated structure of the mineral fiber mat 5 'is preferably composed of divided blanks, preferably sealing with their ren abutting edges bump into each other.

The invention is not shown on the Embodiments limited. It would be so in particular also possible the shielding funnels and rings from two separated by a thermally insulating intermediate layer Layers of wire mesh mats to form, which is preferred in the Way that can happen that the intermediate layer Ceramic fiber material in the form of a fabric, paper, Blankets or fleece exist.

This training can namely in the field of Shielding funnels or rings can also be provided that the elastic storage mat completely over large sections omitted, which in turn has the advantage that none high compressive forces of this elastic fiber mat Wire mesh shielding funnels and shielding rings have to be caught. The manufacture from the Has wire mesh mat instead of the usual metal sheets the advantage that, for example, damage to the Monoliths through the encompassing edge of the Shielding funnel or shielding ring is switched off. However, due to the thermally insulating intermediate layer even without pulling the storage mat over the Area of the rings and shielding funnels too strong thermal heating of the outer shell avoided and on the other side - especially if the thermally insulating Intermediate layer as paper, foil or the like from thermal resistant material is formed - prevents hot exhaust gases in the space between the inner shell and can reach the outer shell, so that there is neither  a heating up, still a blow out of the latest in Area of the monolith existing elastic Can effect mineral fiber mat.

Finally, in this context, it was important noted that due to the mostly given asymmetry of wire mesh mats with regard to their sliding elasticity in different directions Orientation of the mats when installing as a shielding funnel or shielding ring so choose that in the expected greatest stretch direction also the greatest sliding elasticity consists.

Claims (5)

1.Exhaust device with a double-shell housing, the inner shell being mounted at least in sections via an elastic bearing mat, in particular mineral fiber mat, in the outer shell, in particular exhaust-gas cleaning device with an outer housing consisting of two half-shells, in which an elastic bearing mat, in particular a so-called swelling mat, At least one honeycomb-shaped support body and input and output-side inner shielding funnels and, if applicable, shielding rings are mounted between successive carrier bodies, characterized in that the inner housing ( 9 ), in particular the shielding funnels ( 7 ) and rings ( 10 ), consists of a close-knit and in sliding wire mesh mat are formed and are held fixed on both sides. 2. Exhaust gas purification device according to claim 1, characterized in that the shielded funnel ( 7 ) clamped or welded in the connecting piece engages around the end face of the support body ( 4 , 4 ') by clamping. 3. Exhaust gas purification device according to claim 1 or 2, characterized in that the shielding rings ( 10 ) fengfen the adjacent carrier body ends. 4. Exhaust gas purification device according to one of claims 1 to 3, characterized in that the Shielding funnels and rings from two by one  thermally insulating intermediate layer separated Layers of wire mesh mats are formed. 5. Exhaust gas purification device according to claim 4, characterized characterized in that the intermediate layer Ceramic fiber material in the form of a fabric, paper, Blankets or fleece exist.