Abgasheizer

Abstract

Exhaust gas heater (16) for an exhaust system (10) of an internal combustion engine, comprising at least one heating conductor (28, 30) supported on a support structure (18), wherein the at least one heating conductor (28, 30) is wound with respect to a longitudinal axis (A) of the exhaust gas heater and is supported with respect to the support structure (18) by means of a support arrangement (40), wherein the support arrangement (40) provides a plurality of support areas (70) supporting the at least one heating conductor (28, 30) with respect to the support structure (18), characterized in that the at least one heating conductor (28, 30) is movably supported in at least one support area (70) with respect to the support structure (18).

Description

[0001] The present invention relates to an exhaust gas heater for an exhaust system of an internal combustion engine.

[0002] To reduce the pollutant content in the exhaust gas emitted by an internal combustion engine, catalytic converters are used as exhaust aftertreatment units. These units generally reduce the pollutant content through a catalytic reaction. To carry out this catalytic reaction, it is necessary to heat such exhaust aftertreatment units to a relatively high temperature, for example, several hundred degrees Celsius. Particularly during a cold start or prolonged operation at low load, the exhaust gas emitted by an internal combustion engine has a comparatively low temperature. This means that during such operating phases, exhaust aftertreatment units may not reach the temperature required for the catalytic reaction, or may only reach it after a relatively long time, or the temperature may fall below the required temperature for the catalytic reaction to occur.

[0003] To counteract this problem, it is known to install one or more exhaust gas heaters upstream of such exhaust gas treatment units in exhaust systems. These heaters can generate heat by electrically exciting one or more heating elements and transfer it to the exhaust gas flowing through them, or to a gas, such as air, that is passed through the exhaust system before an internal combustion engine is started. This heat is transported by the exhaust gas or gas towards downstream exhaust gas treatment units and transferred to them, so that these units can be brought up to the temperature required for exhaust gas treatment more quickly, or can be reliably maintained at or above this temperature.

[0004] The object of the present invention is to provide an exhaust gas heater which can be reliably operated to heat the gas flowing around it, even under comparatively high mechanical and thermal stress.

[0005] According to the invention, this problem is solved by an exhaust gas heater for an exhaust system of an internal combustion engine, comprising at least one heating conductor supported on a support structure, wherein the at least one heating conductor is wound with respect to a longitudinal axis of the exhaust gas heater and is supported with respect to the support structure by means of a support arrangement, wherein the support arrangement provides a plurality of support areas for the at least one heating conductor supporting the support structure, and wherein the at least one heating conductor is movably supported with respect to the support structure in at least one support area, preferably all support areas.

[0006] Since, in the exhaust gas heater constructed according to the invention, the at least one heating conductor is not rigidly connected to the support structure in at least part of the support areas, but is supported in such a way that it can move relative to the support structure, thermally induced dimensional changes or vibrations or other movements transmitted to an exhaust system cannot lead to damage to the at least one heating conductor or other system components of the exhaust gas heater. For example, the exhaust gas heater can expand when heated and move relative to the support structure, including in the support areas, but remains reliably supported. The maintained support interaction also provides a vibration-damping function, which in particular helps to prevent the excitation of vibrations in a heating conductor.

[0007] In order to introduce the lowest possible flow resistance while maximizing the heat transfer surface area, it is proposed that the at least one heating conductor be designed in a ribbon-like form with narrow sides oriented essentially in the direction of the exhaust gas heater's longitudinal axis and broad sides oriented essentially parallel to the exhaust gas heater's longitudinal axis, wherein the at least one heating conductor is supported on the support arrangement with at least one of its broad sides and / or at least one of its narrow sides.

[0008] Efficient heat transfer to the gas flowing around at least one heating conductor can also be supported, for example, by ensuring that the at least one heating conductor is exposed to the surrounding gas with its narrow and broad sides. This means that the heating conductor is not surrounded by a sheath or similar material that would electrically insulate it and thus shield it from direct contact with the gas.

[0009] Free movement of the at least one heating conductor with respect to the support arrangement can be ensured, for example, by ensuring that in at least one single support area the at least one heating conductor is supported only on an inner side oriented radially inwards in the direction of the exhaust gas heater longitudinal axis with respect to the support structure, or that in at least one single support area the at least one heating conductor is supported only on an outer side oriented radially outwards away from the exhaust gas heater longitudinal axis with respect to the support structure.

[0010] In an alternative embodiment, for a defined holding interaction, the at least one heating conductor can be supported in at least one double support area on an inner side oriented radially inwards towards the longitudinal axis of the exhaust gas heater and on an outer side oriented radially outwards away from the longitudinal axis of the exhaust gas heater, with respect to the support structure. This means that the heating conductor is supported both radially inwards and radially outwards along the same length segment.

[0011] For efficient heating of exhaust gas or gas, at least two heating conductors arranged consecutively in the direction of the exhaust gas heater's longitudinal axis can be provided.

[0012] In order to introduce the lowest possible flow resistance, it is proposed that at least two heating conductors be arranged essentially congruently with each other in the direction of the exhaust gas heater's longitudinal axis.

[0013] For easy connection to an external voltage source, a series connection of the heating conductors can be achieved if two heating conductors arranged immediately one after the other in the direction of the exhaust gas heater's longitudinal axis are electrically connected to each other in inner heating conductor end sections.

[0014] For connection to such an external voltage source, for example the on-board voltage system of a vehicle, a first heating conductor of the at least two heating conductors with a first outer heating conductor end section can provide a first connection area for connection to a voltage source, and a second heating conductor of the at least two heating conductors with a second outer heating conductor end section can provide a second connection area for connection to a voltage source.

[0015] For a simple and reliable support effect, it is proposed that the support arrangement comprises a plurality of support elements mounted on the support structure and extending essentially in the direction of the longitudinal axis of the exhaust gas heater, wherein at least one support element, preferably each support element, comprises a support bolt fixed to the support structure and insulating material in contact with at least one heating conductor, preferably each heating conductor, on the support bolt.

[0016] In at least one support element, preferably each support element, the insulating material can comprise an insulating material coating provided on the support bolt.

[0017] In an alternative embodiment, it can be provided that, in at least one support element, preferably each support element, the insulating material comprises an insulating material sleeve carried on the support bolt in association with at least one heating conductor.

[0018] In order to achieve support acting in the direction of the exhaust gas heater's longitudinal direction by means of the support arrangement, the insulating material of at least one support element, preferably each support element, can have a support formation in association with at least one heating conductor, preferably each heating conductor, which supports the heating conductor in the direction of the exhaust gas heater's longitudinal axis.

[0019] For example, the support formation can include at least one support step, which in a simple design can be provided by the support formation comprising two support steps formed at a depression provided in the insulating material, which accommodates at least one heating conductor.

[0020] To easily implement the aforementioned electrically conductive connection between two heating conductors in their inner end sections, it is proposed that the support arrangement include a connecting element that electrically connects the inner heating conductor end sections. This connecting element can also fulfill a support function for the heating conductors to be electrically connected, particularly in the area of ​​the inner end sections.

[0021] To ensure efficient use of the available volume, it is further proposed that at least one heating conductor be spirally wound with respect to the longitudinal axis of the exhaust gas heater.

[0022] A reliable support interaction, even in the presence of vibrations and thermally induced dimensional changes, can be achieved, for example, if the at least one heating conductor is subjected to radial preload at at least part of the support areas, preferably all support areas.

[0023] A defined positioning of a heating conductor can be further supported by forming a bead-like feature running in the longitudinal direction of at least one heating conductor, preferably along its entire length, preferably in one longitudinal direction. Incorporating such a feature provides the heating conductor with additional stability, which is particularly advantageous when the heating conductor has a comparatively thin, ribbon-like structure.

[0024] The invention further relates to an exhaust system for an internal combustion engine, preferably in a vehicle, comprising an exhaust gas routing component through which gas can flow in a main flow direction and at least one exhaust gas heater constructed according to the invention upstream of at least one exhaust gas treatment unit.

[0025] The invention is described in detail below with reference to the accompanying figures. These show: Fig. 1. In a schematic representation, an exhaust system for an internal combustion engine of a vehicle, Fig. 2 a perspective view of an exhaust gas heater of the exhaust system of the Fig. 1 ; Fig. 3 an axial view of the exhaust gas heater of the Fig. 2; Fig. 4 a detailed view of one of the exhaust gas heaters of the Fig. 2 and Fig. 3 inserted support elements; Fig. 5 a cross-sectional view of a ribbon-like heating conductor for the exhaust gas heater of the Fig. 2 and Fig. 3; Fig. 6 one of the Fig. 3 corresponding axial view of an exhaust gas heater of an alternative design type; Fig. 7 a radially outer section of the exhaust gas heater Fig. 6, viewed in the direction of view VII in Fig. 8; Fig. 8 the detail VIII in Fig. 7, cut along a line VIII-VIII.

[0026] In Fig. 1 is an exhaust system for an internal combustion engine in a vehicle, generally designated by 10. The exhaust system 10 comprises, for example, a pipe-like exhaust guide component 12, composed of several parts, in which exhaust gas emitted from an internal combustion engine generally flows in a main exhaust flow direction H. In a radially expanded area of ​​the exhaust guide component 12, for example, an exhaust treatment unit 14, designed, for example, as a catalyst, is arranged.

[0027] Upstream of the exhaust gas treatment unit 14, an exhaust gas heater, generally designated 16, is arranged. The exhaust gas flowing towards the exhaust gas heater 16 in the main exhaust gas flow direction H can pass through it. During heating operation, the exhaust gas heater 16 transfers heat to the exhaust gas flowing through it, which then flows further downstream through the exhaust gas treatment unit 14 and transfers at least some of the heat absorbed in the exhaust gas heater 16 to the exhaust gas treatment unit 14. In this way, for example, during a cold start phase and especially at comparatively low ambient temperatures, the exhaust gas treatment unit 14 can be brought up to operating temperature quickly and reliably maintained at this temperature during prolonged operation at low load and correspondingly lower exhaust gas emissions.Even before an internal combustion engine is put into operation, heat generated in the exhaust gas heater 16 can be transferred to the downstream exhaust gas treatment unit 14, for example by guiding air through the exhaust gas routing component 12.

[0028] It should be noted that the in Fig. The exhaust system shown in Figure 10 is only a general example of how it can be designed and may differ in various aspects from the one shown in Figure 10. Fig. 1 shown.

[0029] In the Fig. 2 and Fig. Figure 3 shows a first embodiment of the exhaust gas heater 16, which can be used in the exhaust gas system 10. The exhaust gas heater 16 comprises a support structure 18, for example, formed as a sheet metal forming part, essentially pot-shaped, with a base 20 and a circumferential wall 22 used to fix the heater 16 to the exhaust gas routing component 12. The base wall 20 has a plurality of elongated openings 24, extending, for example, circumferentially around a longitudinal axis A of the exhaust gas heater, through which the exhaust gas flowing towards the exhaust gas heater 16 in the main exhaust gas flow direction H can pass. The exhaust gas heater 16 can be arranged in the exhaust gas routing component 12, for example, such that the Fig. 2 and Fig. 3 recognizable, fully open front face 26 of the support structure 18 is oriented in the upstream direction.

[0030] In the illustrated embodiment, the support structure 18, which is generally designed with a pot-like shape, contains two heating conductors 28, 30 arranged successively along the longitudinal axis A of the exhaust gas heater. The two heating conductors 28, 30 are coiled around the longitudinal axis A of the exhaust gas heater in a spiral fashion, thus forming a plurality of radially staggered or overlapping coil sections. Preferably, the two heating conductors 28, 30 are arranged congruently in the support structure 18 along the longitudinal axis A of the exhaust gas heater, so that, in virtually no circumferential area, the second heating conductor 30, positioned further downstream, protrudes beyond the first heating conductor 28, positioned further upstream.

[0031] The two heating conductors 28, 30 are constructed in a ribbon-like fashion from electrically conductive metal material. Each of the two heating conductors 28 has a narrow side 32 oriented towards the upstream direction and a narrow side 34 oriented towards the downstream direction, as well as a broad side 36 oriented radially outwards and thus essentially parallel to the longitudinal axis A of the exhaust gas heater, and a broad side 38 oriented radially inwards and thus also essentially parallel to the longitudinal axis A of the exhaust gas heater.

[0032] The two heating conductors 28, 30 are supported relative to the support structure 18 by means of a support arrangement generally designated 40. The support arrangement 40 comprises a plurality of support elements 42 firmly attached to the base 20 of the support structure 18. Each of the support elements 42 has a support bolt 44 fixed to the base 20, for example by welding, riveting, or the like, and insulating material 46 surrounding the bolt. Since the support bolts 44, as well as the support structure 18, are generally made of electrically conductive metal, the insulating material 46 provides electrical insulation of the heating conductors 28, 30 relative to the support arrangement 40, and thus also to the support structure 18, and also relative to each other.

[0033] The insulating material 46, which can be, for example, a ceramic material, can be provided as an insulating material coating on the support bolts 44. In an alternative embodiment, the insulating material 46 can be provided in the form of insulating material sleeves 48 carried on the support bolts 44. In this case, a separate insulating material sleeve 48 can be provided for each support element 42, corresponding to each of the two heating conductors 28, 30 positioned at an axial distance from one another. In an alternative embodiment, a single insulating material sleeve 48 supporting both heating conductors 28, 30 can be provided for each support element 42.For example, in the length region 48 of such insulating material sleeve 48 lying axially between the two heating conductors 28, 30, a radially outwardly projecting projection area 52 can be provided which provides a support formation 50 for the two heating conductors 28, 30, which ensures that the two heating conductors 28, 30 are axially supported, especially in the direction towards each other, and are thus held at a defined axial distance from each other.

[0034] The inner heating conductor end sections 54, 56 of the two heating conductors 28, 30, which also provide radial inner winding end sections of the two spirally wound heating conductors 28, 30, are supported on a connecting element 58 of the support arrangement 40. The connecting element 58 is also supported on the base 20 of the support structure 18, extending essentially axially, and has, for example, a connecting bolt 60 supported on the base 18. Since this bolt is made of electrically conductive metal, it establishes an electrically conductive connection between the inner heating conductor end sections 54, 56 of the two heating conductors 28, 30. For example, the connecting bolt 60 could also be surrounded by a connecting sleeve 62 made of electrically conductive material, which supports and electrically connects the inner heating conductor end sections 54, 56.

[0035] The two heating conductors 28, 30 are designed for connection to a voltage source, for example, the vehicle's electrical system, by having radially outer heating conductor end sections 64, 66, which also provide radially outer winding end sections of the spirally wound heating conductors 28, 30. For this purpose, the outer heating conductor end sections 64, 66 are, for example, bent radially outwards and extend radially outwards through an opening 68 formed in the circumferential wall 22 of the support structure 18 with connection areas 65, 67. In the exhaust gas routing component 12, openings or feedthroughs can be provided in association with the radially outward extending outer heating conductor end sections 64, 66 and connection areas 65, 67, through which an electrical connection between the heating conductors 28, 30 and the voltage source can be established. It should be noted that, as the Fig. 2 and Fig. 3 this shows that only in the area of ​​these outer heating conductor end sections 64, 66 are the two heating conductors 28, 30 not completely congruent, since, in order to provide a circumferential offset of the two radially outward bent connection areas 65, 67 of the outer heating conductor end sections 64, 66, for example, the outer heating conductor end section 66 of the second heating conductor 30, which is positioned further downstream, extends somewhat further in the circumferential direction than the outer heating conductor end section 64 of the first heating conductor 28, which is positioned further upstream.

[0036] In the exhaust gas heater 16, the two heating conductors 28, 30 are preferably not fixed to any of the support elements 42 with respect to the support structure 18. That is, at each of the support elements 42, the two heating conductors 28, 30 can move relative to the support elements 42 that each provide a support area 70 of the support arrangement 40. In order to nevertheless provide or maintain a defined positioning, the heating conductors 28, 30, which have a spirally wound structure, are shaped such that they bear against the support elements 42 under radial preload, in particular radially inwards, and thus only interact with the respective support elements 42 at their radially inwards oriented broad side 38 in the respective support areas 70.

[0037] Due to this support interaction, which allows movement between the heating conductors 28, 30 and the support arrangement 40, and thus also the support structure 18, the heating conductors 28, 30 can expand, for example, when electrically excited and heated, without causing undefined deformations. Vibrations transmitted to the exhaust gas heater 16 also do not lead to an overload of the mounting points, as there is a fundamental decoupling of movement between the heating conductors 28, 30 and the support arrangement 40. Since the heating conductors 28, 30 are supported under preload and a resulting frictional interaction at the support areas 70, vibration damping is simultaneously achieved when such excitations are transmitted to the exhaust gas heater 16. This damping, in particular, prevents the excitation of vibrations in the resonance range of the heating conductors 28, 30.

[0038] Simultaneously, in the exhaust gas heater 16, the provision of the two heating conductors 28, 30 made of strip-like flat material ensures a very large surface area available for thermal interaction with the exhaust gas or gas to be heated. This surface area is further increased by the use of several heating conductors 28, 30 arranged successively in the flow direction, preferably with essentially identical alignment to one another. Since these are electrically connected in series, a simple method of providing an electrical connection to the radial outside is provided.

[0039] The Fig. Figure 4 shows an alternative embodiment of a support element 42 of the support arrangement 40. In the support element 42, the insulating sleeve 48, provided, for example, in association with the first heating conductor 28, is formed with a radially outwardly open, groove-like recess 72. At its two axial ends, this groove-like recess 72 is bounded by support steps 74, 76, against which the narrow sides 32, 34 of the heating conductor 28 can be supported in the axial direction. By means of the recess 72, which provides a support formation 50 with its two support steps 74, 76, the heating conductor 28 can thus be supported in both axial directions. Since, as the Fig. As illustrated in Figure 4, since the recess 72 has a slightly greater extent in the axial direction than the heating conductor 28, the latter is not rigidly coupled to the support structure 18 in the axial direction, but can, for example, move at least slightly axially with respect to the support structure 18 even in the event of thermally induced dimensional changes. It is self-evident that a corresponding design of the insulating sleeves 48 can also be provided in relation to the second heating conductor 30.

[0040] The Fig. Figure 5 illustrates a further embodiment example of the first heating conductor 28. This conductor has, for example, a radially inwardly oriented, bead-like shape 78 in its central width region located between the two narrow sides 32, 34. The bead-like shape 78 can be continuous along the entire length of the first heating conductor 28, i.e., from the inner heating conductor end section 54 to the outer heating conductor end section 64, or alternatively, it can be provided only in spaced-apart length regions of the first semiconductor 28.

[0041] The bead-like formation 78, which, as in Fig. The bead-like shape 78, which can be recognizable as having a V-shaped, U-shaped, or angular geometry, lends increased strength to the first heating conductor 28, which is constructed with comparatively thin strip material. This helps to keep the first heating conductor 28 in a more defined position, particularly considering its mobility relative to the support structure 18. At the same time, such a bead-like shape 78 could also be used to provide axial support for the first heating conductor 28, especially in interaction with the support elements 42. For example, a recess corresponding to the bead-like shape 78, with respect to its dimensions and shape, can be provided in the insulating material 46, particularly in an insulating sleeve 48 associated with the first heating conductor 28, into which the bead-like shape 78 can be positioned to engage.In this context, it should also be noted that such a design can of course also be provided in conjunction with the second heating conductor 30.

[0042] The preceding discussion referred to the Fig. Sections 2 to 5 describe an embodiment of the exhaust gas heater 10 in which the two heating conductors 28, 30 are supported radially inwards by means of support elements 42, which provide the respective support areas 70. It should be noted that a support interaction could also be realized in which the support elements 42 are positioned radially outside the winding sections of the two heating conductors 28, 30 to be supported by them, so that the two heating conductors 28, 30 are supported by their respective radially outward-oriented broad sides 36 on the support elements 42 or are prestressed against the support elements 42. It is also possible to provide support elements 42 in different circumferential areas or winding section areas of the heating conductors 28, 30, supporting them in different radial directions relative to each other.For example, a change between radially outwardly supporting support elements 42 and radially inwardly supporting support elements 42 can be provided in the circumferential direction. In any case, the support areas 70 provided by the support elements 42 are single support areas 80 in which radial support is provided either only radially inward or only radially outward.

[0043] An alternative design for this is found in the Fig. Figures 6 to 8 are shown. In most of the support areas 70 provided for the exhaust gas heater 16 of this embodiment, two support elements 42, 42' are provided, positioned in the same circumferential area but radially offset from each other. Each such pair of support elements 42, 42', which support the two heating conductors 28, 30 both radially outwards and radially inwards, thus forms a double support area 82 in which the heating conductors 28, 30 are supported both radially inwards and radially outwards. The support elements 42, 42', which provide each double support area 82 and are assigned to each other in pairs, can, for example, be arranged as described above with reference to the Fig. exhibit the structure described in sections 2 to 5.

[0044] One can recognize this particularly in Fig. 6, that a combination of double support areas 82 and single support areas 80 may also be provided, for example if this is necessary for reasons of space. It can be seen that in the Fig. In the area of ​​the exhaust gas heater 16 shown on the right, immediately adjacent to a double support area 82, two support elements 42 are arranged radially and also circumferentially offset from each other, supporting the heating conductors 28, 30 only radially inwards and radially outwards, respectively. These two support elements 42, which are also circumferentially offset from each other, thus each provide a single support area 80, since they do not, in principle, accommodate or clamp the heating conductors 28, 30 running between them in the same longitudinal segment.

[0045] The exhaust gas heater design described above provides a stable structure that efficiently heats exhaust gas or gas. Due to the preferably complete absence of any fixing that would prevent relative movement between the heating elements and the support structure, neither thermally induced dimensional changes nor movements of the heating elements caused by vibration can lead to damage or overloading of the support areas. At the same time, there is considerable flexibility in the dimensioning, particularly of the heating elements, allowing the exhaust gas heater, or such a design, to be easily adapted to the specific heating requirements of an exhaust system.

Claims

[1] Exhaust gas heater for an exhaust system of an internal combustion engine, comprising at least one heating conductor (28, 30) carried on a support structure (18), wherein the at least one heating conductor (28, 30) is wound with respect to a longitudinal axis (A) of the exhaust gas heater and is supported by means of a support arrangement (40) with respect to the support structure (18), wherein the support arrangement (40) provides a plurality of support regions (70) supporting the at least one heating conductor (28, 30) with respect to the support structure (18), and wherein the at least one heating conductor (28, 30) is movably supported in at least one support region (70), preferably all support regions (70), with respect to the support structure (18). [2] Exhaust gas heater according to claim 1, characterized byin that the at least one heating conductor (28, 30) is designed in a band-like manner with narrow sides (32, 34) oriented essentially in the direction of the exhaust gas heater longitudinal axis (A) and broad sides (36, 38) oriented essentially parallel to the exhaust gas heater longitudinal axis (A), wherein the at least one heating conductor (28, 30) is supported by at least one of its broad sides (36, 38) and / or at least one of its narrow sides (32, 34) on the support arrangement (40). [3] Exhaust gas heater according to claim 2, characterized by that the at least one heating conductor (28, 30) is exposed with its narrow sides (32, 34) and its broad sides (36, 38) for contact with the gas flowing around it. [4] Exhaust gas heater according to one of claims 1-3, characterized bythat in at least one single support region (80) the at least one heating conductor (28, 30) is supported only on an inner side oriented radially inwards in the direction of the exhaust gas heater longitudinal axis (A) with respect to the support structure (18), or that in at least one single support region (80) the at least one heating conductor (28, 30) is supported only on an outer side oriented radially outwards in the direction away from the exhaust gas heater longitudinal axis (A) with respect to the support structure (18). [5] Exhaust gas heater according to one of claims 1-4, characterized by in that in at least one double support region (82) the at least one heating conductor (28, 30) is supported on an inner side oriented radially inward in the direction of the exhaust gas heater longitudinal axis (A) and on an outer side oriented radially outward in the direction away from the exhaust gas heater longitudinal axis (A) with respect to the support structure (18). [6] Exhaust gas heater according to one of claims 1-5, characterized bythat at least two heating conductors (28, 30) arranged one after the other in the direction of the exhaust gas heater longitudinal axis (A) are provided. [7] Exhaust gas heater according to claim 6, characterized by that at least two heating conductors (28, 30) are arranged substantially congruent with one another in the direction of the exhaust gas heater longitudinal axis (A). [8] Exhaust gas heater according to claim 6 or 7, characterized by that two heating conductors (28, 30) arranged directly one after the other in the direction of the exhaust gas heater's longitudinal axis (A) are electrically conductively connected to one another in inner heating conductor end sections (54, 56). [9] Exhaust gas heater according to one of claims 6-8, characterized bythat a first heating conductor (28) of the at least two heating conductors (28, 30) with a first outer heating conductor end section (64) provides a first connection region (65) for connection to a voltage source, and that a second heating conductor (30) of the at least two heating conductors (28, 30) with a second outer heating conductor end section (66) provides a second connection region (67) for connection to a voltage source. [10] Exhaust gas heater according to one of claims 1-9, characterized byin that the support arrangement (40) comprises a plurality of support elements (42) carried on the support structure (18) and extending substantially in the direction of the exhaust gas heater longitudinal axis (A), wherein at least one support element (42), preferably each support element (42), comprises a support bolt (44) fixed to the support structure (18) and insulating material (46) on the support bolt (44) in contact with at least one heating conductor (28, 30), preferably each heating conductor (28, 30). [11] Exhaust gas heater according to claim 10, characterized by that in at least one support element (42), preferably each support element (42), the insulating material (46) comprises an insulating material coating provided on the support bolt (44). [12] Exhaust gas heater according to claim 10 or 11, characterized byin that in at least one support element (42), preferably each support element (42), the insulating material (46) in association with at least one heating conductor (28, 30) comprises an insulating material sleeve (48) carried on the support bolt (44). [13] Exhaust gas heater according to one of claims 10-12, characterized by in that, in at least one support element (42), preferably each support element (42), the insulating material (46) in association with at least one heating conductor (28, 30), preferably each heating conductor (28, 30), has a support formation (50) supporting the heating conductor (28, 30) in the direction of the exhaust gas heater longitudinal axis (A). [14] Exhaust gas heater according to claim 13, characterized by that the support formation (50) comprises at least one support step (74, 76). [15] Exhaust gas heater according to claim 14, characterized bythat the support formation (50) comprises two support steps (74, 76) formed on a depression (72) provided in the insulating material (46) and receiving at least one heating conductor (28, 30). [16] Exhaust gas heater according to one of claims 10-15, as far as it refers back to claim 8, characterized by that the support arrangement (40) comprises a connecting element (58) which electrically conductively connects the inner heating conductor end sections (54, 56) to one another. [17] Exhaust gas heater according to one of claims 1-16, characterized by that the at least one heating conductor (28, 30) is wound spirally with respect to the exhaust gas heater longitudinal axis (A), and / or that the at least one heating conductor (28, 30) bears against at least some of the support regions (70), preferably all of the support regions (70), under radial prestress. [18] Exhaust gas heater according to one of claims 1-17, characterized bythat in the at least one heating conductor (28, 30) in at least one length region, preferably in the entire longitudinal extension region of the at least one heating conductor (28, 30) in a heating conductor longitudinal direction, a bead-like formation (78) running in the heating conductor longitudinal direction is formed. [19] Exhaust system for an internal combustion engine, preferably in a vehicle, comprising an exhaust gas guide component (12) through which gas can flow in a main flow direction (H) and at least one exhaust gas heater (16) according to one of claims 1-18 upstream of at least one exhaust gas treatment unit (14).

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