Abstract
An electric heating device in an exhaust gas system, the device having an outer circumferential, circular, housing, wherein a rib structure is arranged in the housing. The rib structure can be heated by applying an electric current. The rib structure is arranged with rib rows parallel to one another in the housing, wherein the parallel-arranged rib rows are arranged such that they are electrically connected to one another in series or in parallel.
Claims
1. An electric heating device in an exhaust gas system, the electric heating device comprising: an outer circumferential housing; and a rib structure arranged in the housing, wherein the rib structure is heatable in response to an electric current applied thereto, the rib structure comprises a plurality of rib rows parallel to one another in the housing, each rib row of the plurality of rib rows comprises a plurality of ribs, the plurality of rib rows are electrically connected to one another in series or in parallel, wherein two holding rods extend through the plurality of rib rows to hold the plurality of rib rows in place within the housing, and wherein each rib row of the plurality of rib rows has widened regions through which the two holding element extend.
2. The electric heating device according to claim 1, wherein the housing comprises a radially circumferential lateral surface.
3. The electric heating device according to claim 1, wherein the plurality of rib rows are parts of a continuous sheet metal strip.
4. The electric heating device according to claim 1, further comprising an electrically conductive connecting element arranged in a respective end region of each rib row of the plurality of rib rows.
5. The electric heating device according to claim 4, wherein the connecting element comprises a contact plate.
6. The electric heating device according to claim 1, further comprising an electrically insulating spacer arranged in a respective end region of each rib row of the plurality of rib rows.
7. The electric heating device according to claim 6, wherein the spacer is coupled to the housing.
8. The electric heating device according to claim 1, wherein a width of each rib row of the plurality of rib rows varies along an exhaust gas flow direction.
9. The electric heating device according to claim 1, wherein the holding elements comprises a plurality of plug-in sleeves coupled together.
10. The electric heating device according to claim 1, wherein each rib row of the plurality of rib rows comprises an electric conductor plate and a rib plate coupled to the electric conductor plate.
11. The electric heating device according to claim 10, wherein, in each rib row of the plurality of rib rows, fewer of the ribs are arranged in an end region of the rib plate than in a center region of the rib plate, wherein the center region extends over a majority proportion of a length of the rib plate.
12. The electric heating device according to claim 1, wherein the housing is circular.
13. The electric heating device according to claim 4, wherein the connecting element comprises a contact lug.
14. The electric heating device according to claim 4, wherein the connecting element comprises a bracing plate.
15. The electric heating device according to claim 6, wherein the spacer comprises a ceramic plate.
16. The electric heating device according to claim 6, wherein the spacer is coupled to the housing, and the spacer extends partially through the housing.
17. An electric heating device in an exhaust gas system, the electric heating device comprising: an outer circumferential housing; a rib structure arranged in the housing, wherein the rib structure is heatable in response to an electric current applied thereto, the rib structure comprises a plurality of rib rows parallel to one another in the housing, each rib row of the plurality of rib rows comprises a plurality of ribs, a longitudinal axis of the heating device is arranged at an angle of greater than 1 degree with respect to a longitudinal axis of an exhaust gas post-treatment component in an exhaust gas flow direction, wherein two holding rods extend through the plurality of rib rows to hold the plurality of rib rows in place within the housing, and wherein each rib row of the plurality of rib rows has widened regions through which the two holding element extend.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Further features, characteristics, and aspect of the present disclosure are described in the following figures. These serve for easy understanding of the disclosure. In the figures:
(2) FIG. 1 shows a partial detail of an exhaust gas jet according to at least one embodiment,
(3) FIG. 2 shows a perspective view of the heating device according to at least one embodiment,
(4) FIG. 3 shows an enlarged illustration of the rib rows in a partial sectional view according to at least one embodiment,
(5) FIG. 4 and FIG. 5 show schematic illustrations of different couplings of the individual rib rows according to at least one embodiment,
(6) FIG. 6 shows a two-part illustration of the rib rows according to at least one embodiment,
(7) FIG. 7A shows a perspective view analogously to FIG. 2 according to at least one embodiment,
(8) FIG. 7B shows a longitudinal sectional view with respect to FIG. 7A according to at least one embodiment,
(9) FIG. 8A and FIG. 8B show design variants of the heating device according to one or more embodiments,
(10) FIG. 9 shows embodiment variants,
(11) FIG. 10A to FIG. 10D show a design with the holding rods according to one or more embodiments,
(12) FIG. 11A and FIG. 11B show different holding rods according to one or more embodiments,
(13) FIG. 12 shows spacers, fastened to the housing according to at least one embodiment,
(14) FIG. 13 shows two holding rods made from ceramic according to at least one embodiment; and
(15) FIG. 14 shows an angled arrangement of the heating element and catalytic converter with respect to one another according to at least one embodiment.
DETAILED DISCLOSURE
(16) FIG. 1 shows a partial detail of an exhaust gas system in an exploded illustration. An exhaust gas post-treatment component in the form of a catalytic converter 2 is illustrated herein. In the exhaust gas flow direction A, a heating coil in the form of a heating device 3 is connected upstream of the catalytic converter 2. This heating coil is wound in a meandering manner. Within the scope of this disclosure, a meandering path is understood to mean a meandering path or zig-zag path.
(17) An outer housing 4, in which the heating coil is inserted, is furthermore illustrated, and this housing 4 has an electrical connection 5 in order to apply an electric current to the heating coil.
(18) FIG. 2 shows a perspective view of a heating device 3. This has an outer housing 4. The housing 4 is a radially circumferential sheet metal jacket. This can have a small width B in the exhaust gas flow direction A. However, the housing 4 can also be designed to be considerably longer in the exhaust gas flow direction, as illustrated here. Two electrical connections 5 are furthermore provided for applying an electric current to the rib structure 6 arranged in the heating device 3. According to the disclosure, individual rib rows 7 are arranged in the heating device 3. As seen locally, the rib rows 7 are arranged parallel above one another relative to a horizontal direction H illustrated here.
(19) The individual rib rows 7 are now electrically connected to one another in series so that the electric current flow E, likewise illustrated by a dashed line, is produced in a meandering manner. To this end, contact plates 9 are arranged in the respective end regions 8 of the rib rows 7, which is also illustrated in FIG. 3, which shows an enlarged illustration of the rib rows 7 in a partial sectional view. The contact plates 9 are only arranged between every second rib row 7 in each case, so that the meandering electric current flow E is produced.
(20) So that the rib rows 7 are themselves held in the housing 4, a holding element in the form of a holding rod 10, in this exemplary embodiment in the form of two holding rods 10, is furthermore provided. The holding rod 10 extends through all rib rows 7 relative to the vertical direction V and is coupled to the housing 4 at the top and bottom in each case, as illustrated in FIG. 2. The rib rows 7 are therefore arranged in a fixed position in the exhaust gas flow direction A and at a parallel spacing from one another.
(21) As illustrated in FIG. 3, the holding rod 10 can be formed from a metallic inner rod 11 and, for example, ceramic spacer sleeves 12, wherein a spacer sleeve 12 is itself associated with each rib row 7.
(22) According to FIG. 4 and FIG. 5, different mutual couplings of the individual rib rows 7 are illustrated schematically. As illustrated in FIG. 6, the rib rows 7 themselves are formed in two parts. These have a current-conducting plate 13 and a rib plate 14, also known as a fin plate, arranged thereon. The current-conducting plate 13 and rib plate 14 are then coupled, for example, with material fit via a soldering procedure or the like. According to embodiment variants of FIG. 6, two rib rows 7 can be bent in their end region 8 as a result of a bending procedure. Each rib row 7 can also be produced separately. As already mentioned in the description, all rib rows 7 are produced from one piece and are then produced in a bending technique and extend in a meandering manner.
(23) According to FIG. 4, the individual rib rows 7 are coupled to one another in their respective end region 8 via a contact lug 15. This means that the current-conducting plate 13 is designed to be longer, is bent and is coupled one to another, for example, via a spot weld P or the like.
(24) According to the design variant of FIG. 5, the rib rows 7 are coupled to one another in their end regions 8 via a bracing plate 16. This bracing plate 16 is itself formed in a C shape, for example. The bracing plate 16 then connects two rib rows 7 and current-conducting plates 13 to one another in the end regions 8 in each case, but always leaves out a coupling inbetween so that a meandering electric current flow E again results in an electrical series connection of the rib rows 7 here.
(25) FIG. 7A and FIG. 7B show a perspective viewaccording to FIG. 7A, analogously to FIG. 2 only without showing the current flow. FIG. 7B shows a longitudinal sectional view through FIG. 7A. In the longitudinal sectional view, the holding rods 10 are arranged in a fixed position with respect to one another, reaching through the individual rib rows, relative to the vertical direction V. The electrical insulation with respect to the housing 4 is present at the electrical connections 5; the electrical connection is consequently connected to the rib structure in a current-conducting manner but is arranged to be electrically insulated from the housing 4. The contact plates are, on the one hand, arranged in the respective end regions. Additional spacer plates 17 are arranged between them; an additional spacer plate 17 is arranged for every second rib row 7 in each case. The spacer plate 17 is produced from a ceramic material.
(26) FIG. 8A and FIG. 8B show a design variant of the heating device 3. In this case, respective rib rows 7 are in turn connected to one another in a meandering manner via a continuous current-conducting plate 13. Alternatively, the connections, already arranged in FIG. 3, FIG. 4, and FIG. 5, can also be produced in the end region 8 between two adjacent rib rows 7. However, in this case, the width B of the rib rows 7, as measured in the exhaust gas flow direction A, is designed to vary. This means that the width B changes in the longitudinal direction L of the rib rows 7. The width B itself is measured in the exhaust gas flow direction A. The width is therefore designed to be greater in the region of the holding rods 10. The same area is therefore effectively also available in the region of the holding rods 10 so that substantially the same heat transmission can be observed over the entire cross-section of the heating device 3 and an exhaust gas flow which is heated uniformly in cross-section can be generated.
(27) FIG. 9 shows at least one embodiment variant. In this case, a continuous current-conducting plate 13 is also folded or bent in one piece. Two rib rows 7 are directed such that they are parallel-facing one another, wherein two layers of the current-conducting plate 13 are subsequently in turn arranged at a spacing from one another, albeit without a rib row 7, in turn followed by two rib rows 7 arranged parallel to one another. This enables simple production during a bending procedure of the rib structure arranged in the housing 4. This is in turn held by the holding rods 10 and connected to the electrical connections 5.
(28) As is shown at least on the right-hand side of FIG. 9, the density of the ribs is designed to be lower in the respective end region 8 of the rib rows 7. A possibly turbulent flow and/or compaction of the flow can result in excessive heating in the end region of the housing 4 here, which can be compensated or avoided by a lower density of the ribs in the end region 8.
(29) FIG. 10A, FIG. 10B, FIG. 100, and FIG. 10D show the design with the holding rods 10, wherein the holding rods 10 are not formed continuously in one piece here, but by respective plug-in sleeves 18. A respective ceramic plug-in sleeve 18 can therefore fix the respective rib row 7 in position with form fit as well as electrically insulate rib row 7 from another. The plug-in sleeve 18 can therefore function simultaneously as a spacer and as an electrical insulator. A metallic sleeve 19, for example, can be arranged at the ends of the holding rods 10 in order to be coupled to the housing 4. This embodiment variant also has a continuous current-conducting plate 13 between the rib structures. However, this is arranged in a meandering manner in each case, so that a rib row is arranged parallel to the next rib row 7 on the current-conducting plate 13 in each case. The spacer sleeves 12 can therefore be inserted during the folding procedure and are held by the mutually bent rib rows 7 themselves. The overall structure can then be subsequently inserted into the housing 4 and fixed in position with form fit by the sleeves 19.
(30) FIG. 10B, FIG. 100, and FIG. 10D show a respective longitudinal sectional view, perspective top and bottom view of such a rib row 7. The rib row 7 has a current-conducting plate 13 and a rib plate 14. Indicated therein are the spacer sleeves 12 as ceramic sleeves, which simultaneously realize electrical insulation as well form-fitting positional fixing. The current-conducting plate 13 and the rib plate 14 according to the overall disclosure can be formed from a high-grade steel material, which has a thickness or wall thickness of 0.1 to 0.2, or 0.15 mm.
(31) In contrast, FIG. 11A and FIG. 11B show an embodiment variant in which a respective rod 11 is formed to reach through the rib rows 7 in one piece. Respective spacer sleeves 12 are arranged as electrical insulators here, which spacer sleeves space the individual rib rows 7 with respect to one another with form fit and electrically insulate them from one another.
(32) FIG. 12 shows a further design variant of the present disclosure. In this case, contact plates for the respective rib rows 7 are arranged in the end region, specifically between every second rib row 7. Spacer plates 17, as ceramic plates, are then furthermore also arranged between every second rib row 7 in each case. They are arranged here such that they reach partially through the housing 4 and have a hole so that they are reached-through outside the housing 4 and are held in a fixed position by means of a weld spot 21. The spacer plates 17 can therefore be subsequently inserted into the housing 4 and fixed in position here with form fit.
(33) FIG. 13 shows a further design variant of the disclosure. The respective rod 11 is formed as a ceramic rod here, so that is arranged holding the rib rows 7 at a spacing with form fit but, at the same time, from in electrically insulating fashion. The entire product can be produced separately, consequently the rib structure and then are inserted into the housing. Pre-assembly can also take place and then overall soldering of the entire structure can take place in a soldering device.
(34) FIG. 14 shows at least one embodiment of the disclosure, according to which an angled arrangement is geometrically decoupled and possible in any desired manner within the scope of this disclosure. To this end, the heating device 3 can be arranged with its longitudinal axis 22 at an angle of greater than 1 degree with respect to a longitudinal axis 23 of the catalytic converter 2 or the exhaust gas post-treatment component. This gives a greater creative degree of freedom in terms of the path of the exhaust gas system 1, for example, in the underfloor region of the motor vehicle. This arrangement provides for optimum use of the installation space for axle-component transmissions, components or an internal combustion engine. As a result of the physical decoupling of the heating device 3 and exhaust gas post-treatment component, the angled arrangement can be freely selected, as is illustrated in FIG. 14.
(35) The foregoing description of some embodiments of the disclosure has been presented for purposes of illustration and description. The description is not intended to be exhaustive or to limit the disclosure to the precise form disclosed, and modifications and variations are possible in light of the above teachings. The specifically described embodiments explain the principles and practical applications to enable one ordinarily skilled in the art to utilize various embodiments and with various modifications as are suited to the particular use contemplated. Various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the disclosure.
