Assembly of a metal discoid honeycomb structure and a support structure and use of said assembly, gas heater and production of said gas heater
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- EMITEC TECH GMBH
- Filing Date
- 2026-01-30
- Publication Date
- 2026-08-06
Smart Images
Figure EP2026052516_06082026_PF_FP_ABST
Abstract
Description
[0001] Arrangement of a metallic disc-shaped honeycomb structure and a support structure and their use, gas heater and its manufacture
[0002] The present invention relates to an arrangement of a metallic disc-shaped honeycomb structure and a support structure, a gas heater and its manufacture.
[0003] Gas flows, particularly exhaust gas flows from a combustion process, may need to be heated to a predetermined temperature before being used in further processes, such as catalytic exhaust aftertreatment. For this purpose, the gas flow can pass through an apparatus that heats or warms it. For this, for example, honeycomb structures are known that are electrically heatable, especially because they are made of a material that undergoes resistance heating when an electrical voltage is applied.
[0004] A gas heater for automotive applications is described, for example, in EP 4314508 A1. This heater is designed as an electrically heated disc with a disc-like support element featuring ribs. The honeycomb structure used is designed as a heating disc with limited axial extent and is connected to a voltage source, allowing it to be heated by utilizing its ohmic resistance. The exhaust gas flowing around the heating disc is thus heated, which in turn heats the catalysts subsequently through which the exhaust gas flows. The light-off temperature is therefore reached significantly earlier compared to a non-electrically heated exhaust system.
[0005] Depending on the type of gas treatment, the spatial environment, and / or the application area, the specific design requirements for the gas heater can vary considerably. This applies particularly to the electrical connections and / or the housing design of the gas heater. Therefore, there is a need for the widespread use of such gas heaters because they can efficiently and quickly establish reaction conditions in the gas stream that are essential for many environmentally relevant processes.
[0006] Starting from this, the object of the invention is to at least alleviate the problems described with reference to the prior art and, in particular, to show a way to make the provision of such gas heaters more flexible.
[0007] These problems are solved by an arrangement having the features of claim 1 and its use according to claim 8. Furthermore, the method with the steps of claim 9 and an electrically heated gas heater according to claim 10 contribute to this.
[0008] Preferred embodiments of the invention are specified in the dependent claims. The description, particularly in conjunction with the figures, explains the features of the claims and provides further exemplary embodiments. The features of the claims can be combined with one another and can also be supplemented or clarified by features of the description.
[0009] This is achieved by an arrangement comprising at least one metallic disc-shaped honeycomb structure and at least one support structure. Preferably, the arrangement has only a single, one-piece support structure. It is possible, for example, that a honeycomb structure is arranged on both sides of the support structure; however, it is preferred that a single honeycomb structure is formed only on one side of the support structure.
[0010] The at least one disc-shaped honeycomb structure is formed by a plurality or multiple of metal foils, which together form at least one layer stack. At least some of the metal foils are structured, for example, exhibiting a corrugated structure with crests and troughs. It is possible that all metal foils form a corrugated structure, whereby the corrugation height and / or width may differ from one another. It is possible that some of the metal foil(s) are smooth or uncorrugated. The metal foils or sections thereof can be laid on top of each other or stacked to form a layer stack. The layer stack can, for example, comprise 3 to 10, in particular 3 to 5, stacked metal foils (sections). It is possible that the honeycomb structure has more than one layer stack, which are arranged, in particular, electrically insulated from one another or spatially spaced apart.In particular, it is possible that two, three, four or six layer packages are provided.
[0011] The metal foils form a multitude of honeycombs within the at least one layer stack. The honeycombs are defined directly by the corrugated structure. Specifically, the honeycombs are formed between two adjacent (micro-)corrugated or smooth and corrugated metal foils. The honeycombs are formed only between the metal foil sections of a layer stack, i.e., they are fully integrated into the layer stack. The honeycombs can have a cross-sectional area of, for example, 4 to 11 mm². 2 [square millimeters] and / or a density of 60 to 150 cpsi, in particular 100 to 140 cpsi, ["cells per inch"]. It is possible that the corrugated structure of the metal foils in one or more layer packs may differ.
[0012] The honeycomb structure is disk-shaped but can span any cross-section, such as a circle, oval, polygon, or similar shape. The cross-sectional shape of the honeycomb structure is typically described by its radius or diameter. The radial extent of the honeycomb structure is many times greater than its axial extent. For example, the radial extent of the honeycomb structure can range from 50 to 350 mm [millimeters], while the axial extent is from 5 to 20 mm [millimeters].
[0013] The at least one layer stack, or all layer stacks, has a first layer end and an (opposite) second layer end. The lateral edges of the metal foils are arranged at the layer end. It is possible that the layer stack is thinner or more compressed in the layer end region compared to the (predominant) central layer stack section. For example, the honeycomb cross-section and / or the honeycomb density may be (significantly) smaller there than in the (predominant) central layer stack section. It is possible that the metal foils in the layer end region are deformed in such a way that a corrugated structure is flattened and, if necessary, irregularly shaped. Preferably, the layer end has a length of 40 to 90 mm, or a maximum of 2 to 15% of the total layer stack length.
[0014] Between the layer ends, the layer stack section(s) can be arranged in a twisted or wound configuration, such that the layer stack does not make (electrical) contact with itself (on the outside) between the layer ends. The layer stack can be arranged in an S-, W-, M-, or V-shape between the layer ends. In particular, the arrangement is such that an outer cover metal foil of the layer stack is only in (electrically conductive) contact with a metal foil located further inside the layer stack. It is possible that a (free) gap and / or an electrical insulating material is arranged in the twists, windings, etc., of the layer stack termination.
[0015] The first and second layer ends are arranged at a circumferential edge of the honeycomb structure (especially on the radial outer edge). The layer ends can be positioned, for example, opposite each other (approx. 180°), or together in an approx. 30° circumferential section, or in an approx. 60° circumferential section.
[0016] The first and second layer ends are each provided with an external contact plate, which is otherwise exposed. The contact plate is attached to the layer end only on one side; in particular, the opposite side of the contact plate is freely accessible (especially from the radial outside). Specifically, an outwardly facing side of the contact plate is "free" in the sense that there is a clearance in the radial direction that encloses at least 80% of the contact plate side, and in particular, completely covers it (100%). The contact plate can, for example, have a height and length in the range of 5 to 15 mm. It is possible that the contact plate extends beyond the layer stack on one or both sides in the axial direction.
[0017] The at least one support structure is also disc-shaped, in particular, for example, in the form of a stamped sheet metal part or the like. It is possible that the support structure comprises superstructures, such as lamellae, webs, or the like, extending axially from a planar metal frame. The support structure comprises, in particular, a circumferential outer frame, support arms extending into the interior of the frame, and possibly also a centrally arranged inner frame to which at least some of the support arms terminate. The cross-section of the support structure can have a multitude of openings, such that the cross-section is open to at least 50%, and in particular at least 80%.
[0018] The support structure is connected to the metallic honeycomb structure by a multitude of support pins, thus establishing a predetermined distance between the support structure and the honeycomb structure. It is possible that at least some of the support pins form a (structural) bond. The support pins may be either embedded in corresponding reservoirs (e.g., on the support arms) of the support structure and / or embedded in the cells of the honeycomb body and / or (preferably by a material bond). It is possible that the support pins and / or their attachment to the support structure or honeycomb structure provide electrical insulation.
[0019] The support structure and honeycomb structure are aligned such that their (axial) distance from each other is essentially the same across the cross-section. This distance is preferably in the range of 2 to 7 mm [millimeters].
[0020] The contact plates can be flush with the layer ends. In other words, this means, in particular, that the outer edge of the layer stack (in the direction of the layer stack) is essentially flush with the outer edge of the contact plate. Furthermore, they do not extend substantially over the length (in the direction of the layer stack) and height of the respective layer end.
[0021] The contact plates can be manufactured with a sheet thickness (in the radial direction) ranging from 1 to 4 mm [millimeters]. In particular, the sheet thickness is many times greater than the foil thickness of the metal foils of the layer stack. It is possible that the sheet thickness is at least 50% of the thickness (in the radial direction) of the (tapered or compressed) layer end of the layer stack, and possibly even at least 100%.
[0022] For the contact plates, especially when used in the exhaust system of an internal combustion engine, one of the following groups is suitable: austenitic stainless steel, ferritic stainless steel, heat-resistant stainless steel, corrosion-resistant stainless steel; in particular one of the following steel material numbers: 1.4301, 1.4509, 1.4571, 1.4828.
[0023] The contact plates can be arranged on the outer circumference of the honeycomb structure and / or the support structure. It is possible that the contact plates, alone or possibly together with outer sections of the support structure, form the outermost radial part of the arrangement. The contact plates can then serve, in particular, as a (detectable) alignment aid in case of rotation or displacement of the arrangement during subsequent assembly steps. Furthermore, a (radial) preload can be adjusted in the area of the contact plates during the assembly of electrode connections.
[0024] The contact plates can be soldered (on one side) to the layer ends.
[0025] It is possible that the contact plates are essentially smooth or flat.
[0026] The support structure can have multiple or even numerous mounting tabs that surround the honeycomb structure, spaced apart both circumferentially and radially. The mounting tabs may be arranged essentially on a circumferential edge, with the layer end or contact plate also located on this edge or even (partially) projecting radially outwards. The mounting tabs can extend across the distance to the honeycomb body and further beyond a certain height of the honeycomb body (in the axial direction), preferably also extending beyond the height of the contact plate. The mounting tabs do not cover the contact plates radially. It is possible that the at least two contact plates are spaced apart circumferentially by at least one mounting tab.
[0027] The mounting tabs can later be oriented in one of two directions on the casing: (a) away from the heated honeycomb structure and / or (b) past the heated honeycomb structure. Variant (a) has the advantage that the diameter of the heated honeycomb structure can be made slightly larger because less space is required between the casing and the honeycomb structure, although the potential disadvantage is that the overall length increases. Variant (b) is shorter overall, but has a slightly smaller heated honeycomb structure.
[0028] The fastening tabs can each form a hinge section, allowing the position of the fastening tabs relative to the honeycomb structure to be elastically deformable. The hinge section can be designed, in particular, to allow the fastening tab to be tilted radially and / or inclined circumferentially. The hinge section can be formed by a tapered tab base, which, for example, allows the tab to be attached to an outer frame of the support structure.
[0029] The support structure can include support arms extending across the cross-section of the casing or the honeycomb structure, which (at least partially) extend approximately to or between the mounting tabs. Depending on the load (dead weight of the honeycomb structure; natural frequency behavior of the honeycomb structure; stress from gas pulsations and / or gas temperatures and / or vibration excitation from the motor; etc.), the support structure can be designed accordingly. This can be achieved by adjusting the width and thickness of the support arms, the number of support arms, and / or the pre-installed mounting points on the casing.
[0030] According to another aspect, the use of the proposed arrangement for the flexible manufacture of various electrically heated gas heaters is suggested here, wherein the gas heaters in particular have different electrode connections and / or jacket housings.
[0031] In particular, its use serves to compensate for (significant) tolerances of different components in series production and / or to combine or install the (same) arrangement with different electrode connections and / or casings by adjusting the position of the contact plate and / or mounting tab.
[0032] According to yet another aspect, a method for manufacturing an electrically heated gas heater is proposed, which includes at least the following steps:
[0033] a) Providing a prefabricated arrangement of the type proposed here; b) Determining an electrical connection configuration and / or an enclosure configuration;
[0034] c) Inserting the assembly with the determined connection configuration and / or an enclosure configuration into a jacketed housing;
[0035] d) Attaching the at least one support structure to the casing; e) Attaching electrode connections to the contact plates of the honeycomb structure.
[0036] The steps listed need not be performed in the order shown. For example, steps a) and b) may be performed partially simultaneously or in reverse order. For example, steps d) and e) may be performed at least partially simultaneously. Step a) may, in particular, include the fabrication of the arrangement, after which the arrangement may be provided in an assembly frame as a component for the manufacture of the gas heater. The fabrication may, for example, include one or more of the following, in particular all of the following processes: a)1: Waves of metal foil
[0037] a)2: Application of solder paste to (a) selected connection areas of the metal foils and to (b) the contact sheets and to (c) the support structure a)3: Stacking of the metal foils and, if necessary, cutting of the layer stack
[0038] a)4: Winding the layer stack, if necessary using a winding aid or die. a)5: Attaching the contact plates to the layer ends.
[0039] a)6: Gluing / soldering of metal foils and / or support pins
[0040] a)7: Positioning the support pins towards the honeycomb and support structure
[0041] a)8: Soldering
[0042] Step b) may, in particular, include determining the electrical connection configuration and / or an enclosure configuration visually, sensorily, and / or digitally / computationally. The electrical connection configuration may, for example, be predetermined based on at least one of the following parameters: electrode design, electrode material, electrode position or orientation, electrode connection method, operating voltage, current-carrying capacity (especially in the range of approximately 6-7 A / mm²). 2 [Amperes / square millimeter]. The enclosure configuration can be predetermined, for example, depending on at least one of the following parameters: cross-section or design of the casing, position and size of the electrode openings in the casing, method for connecting the casing to the support structure, material of the casing, etc.
[0043] In step c), the arrangement is pre-positioned in the casing, specifically with a predetermined orientation (rotation), and / or with a suitably designed and aligned / pre-configured (especially reshaped) design of the layer stack ends or contact plates and / or the mounting tabs. Depending on the timing of the determination after step b), this adjustment or pre-configuration of the arrangement can take place during step a) and / or after step b), e.g., before, during, and / or after step c).
[0044] Once the predetermined electrical connection configuration or enclosure configuration is achieved, the assembly can be joined to the outer casing (step d)) and the electrodes can be joined to the contact plates through the outer casing (step e)).
[0045] Step d) can include pressing the assembly in so that the mounting tabs are in contact with the inside of the casing (particularly in one plane). The casing and mounting tabs can then be joined together by a resistance welding process.
[0046] In step e), the electrodes can be inserted radially through electrode openings in the casing and brought into (direct) contact with the covering contact plates. The electrodes are preferably attached to the contact plates by stud welding. The electrode openings can then be sealed by IG welding with a protruding portion of the electrodes (or their feedthrough sleeves).
[0047] Furthermore, an electrically heated gas heater is proposed, manufactured according to the method described herein, wherein the honeycomb structure formed by the metal foils is at least partially coated with a catalytically active coating for exhaust gas aftertreatment. The catalytically active coating can be applied to all metal foils and / or all inner surfaces of the honeycomb structure. The catalytically active coating is specifically designed to convert at least one gas component of the exhaust gas from a (mobile or stationary) internal combustion engine. Naturally, the gas heater can also be designed to heat not only the gas flowing through it, but also any particles and / or liquids contained therein. It is also possible for the gas heater to be used (temporarily) to vaporize liquid or liquid droplets carried in the gas flow and / or located / applied to the honeycomb structure.
[0048] The invention and its technical context are explained in more detail below with reference to the figures. The figures show particularly preferred embodiments, to which, however, the invention is not limited. It should be noted in particular that the figures, and especially the depicted dimensions, are only schematic. They show:
[0049] Fig. 1: an embodiment of an arrangement consisting of a honeycomb structure and a support structure;
[0050] Fig. 2: a first exemplary detail of a honeycomb structure;
[0051] Fig. 3: a second exemplary detail of a layer end with contact plate;
[0052] Fig. 4: an embodiment of a gas heater; and
[0053] Fig. 5 illustrates the manufacture of a gas heater using the prefabricated arrangement.
[0054] Fig. 1 shows an embodiment of an arrangement 1 consisting of a honeycomb structure 2 and a support structure 3.
[0055] The honeycomb structure 2 is metallic and disc-shaped and comprises a single layer stack 5. The honeycomb structure 2 is formed by a plurality of metal foils 4. Each metal foil 4 forms at least one layer stack 5.
[0056] The layer stack 5 has a first layer end 6 and a second layer end 7. The layer ends 6 and 7 are arranged opposite each other with respect to the layer stack 5 (when straight and extended). Between the layer ends 6 and 7, the layer stack 5 is wound, forming a spiral. The layer stack 5 is wound between the layer ends 6 and 7 in such a way that it does not make (electrical) contact between them. This is achieved by providing a (uniformly wide) gap 28 between the sections of the layer stack 5 and its windings. An electrical insulating material can also be provided, at least partially or locally, in the gap 28.
[0057] The first layer end 6 and the second layer end 7 are each provided with an external contact plate 10, 11, which is otherwise exposed. The contact plates 10, 11 are attached to one side of the respective layer end 6, 7, so that the opposite side of the contact plate is freely accessible.
[0058] The first layer end 6 and the second layer end 7 are arranged on a (particularly radially outer) circumferential edge 9 of the honeycomb structure 2. The circumferential edge 9 lies on an outer circumference 17 of the honeycomb structure 2. The contact plates 10, 11 are positioned on the outer circumference 17 of the honeycomb structure 2 and are therefore exposed and accessible from the outside.
[0059] The honeycomb structure 2 is connected to the support structure 3 by means of a plurality of support pins 12. A predetermined distance 13 is set between the support structure 3 and the honeycomb structure 2. The distance 13 is measurable in an axial direction 21 of the arrangement 1.
[0060] The axial direction 21 runs perpendicularly through the honeycomb structure 2. A radial direction 20 runs transversely to the axial direction 21. A circumferential direction 19 runs around a center of the honeycomb structure 2.
[0061] The support structure 3 has a plurality of fastening tabs 18 that surround the honeycomb structure 2 at intervals both in the circumferential direction 19 and in the radial direction 20. Each fastening tab 18 forms a hinge section 22, allowing the position of the fastening tabs 18 relative to the honeycomb structure 2 to be deformably adjusted. Fig. 2 shows a first exemplary detail of the honeycomb structure 2. The detailed view shows a layer stack 5 with a plurality of metal foils 4 stacked on top of each other. The metal foils 4 have a corrugated structure with crests and troughs, with the corrugations alternating between stronger and weaker. The metal foils 4 form a plurality of axially extending honeycombs 8 within the layer stack 5. A catalytically active coating 27 is also applied to the metal foils 4.
[0062] Fig. 3 shows a second exemplary detail of the first layer end 6 with the first contact plate 10. The details shown are analogous to the second layer end 7 and the associated second contact plate 11. It can be seen how the contact plate 10 is attached to the first layer end 6 on one side. The layer stack 5 is thinner or more compressed in the region of the first layer end 6 compared to the adjacent central sections of the layer stack 5. The first contact plate 10 has a thickness of 16. The first contact plate 10 is approximately flush with the first layer end 6. An outer edge of the layer stack 5 is substantially flush with the outer edge of the contact plate. In particular, the first contact plate 6 does not extend substantially over a length 14 (in the direction of the layer stack 5) and height 15 of the first layer end 6.
[0063] Fig. 4 shows an embodiment of a gas heater 23. The gas heater 23 has a first electrode connection 24 and a second electrode connection 25, which project through a casing 26. The casing 26 is cylindrical and contains the honeycomb structure 2 with the support structure 3. The honeycomb structure 2 is electrically connected at its first layer end 6 to the first contact plate 10 at the first electrode connection 24, which penetrates the casing 26, and at its second layer end 7 to the second contact plate 11 at the second electrode connection 25, which penetrates the casing 26 at a distance. The support structure 3 is held on an inner side of the casing 26 by the mounting tabs 18. The free gap 28 is visible between the turns of the layer stack 5. The cross-section of the support structure 3 has a plurality of openings 29.
[0064] Such a gas heater 23 can, for example, be integrated into a vehicle's exhaust system and connected externally to the vehicle's electrical system. A control unit can be provided that supplies the honeycomb body 2 with electrical current via the electrode connections 24, 25 as needed, so that the metal foils heat up and transfer heat to the gas flow passing through the casing 26.
[0065] Fig. 5 illustrates the manufacture of the gas heater 23 with the prefabricated arrangement 1. In step a), the prefabricated arrangement 1 of the type proposed here is prepared. In step b), an electrical connection configuration for the gas heater 23 and / or an enclosure configuration is determined in the jacket housing 26. In step c), the arrangement 1 with the determined connection configuration and / or the enclosure configuration is inserted into the jacket housing 26. In step d), the support structure 3 is attached to the jacket housing 26 by means of the mounting tabs 18. In step e), the electrode connections 24, 25 are attached to the contact plates 10, 11 of the honeycomb structure 2. Steps d) and e) can be carried out at least partially simultaneously. Reference numeral list
[0066] 1. Arrangement
[0067] 2 honeycomb structure
[0068] 3 Support structure
[0069] 4 metal foil
[0070] 5-layer package
[0071] 6 first layer end
[0072] 7 second layer end
[0073] 8 honeycomb
[0074] 9 Circumferential border
[0075] 10 first contact plate
[0076] 11 second contact plate
[0077] 12 Support pin
[0078] 13 distance
[0079] 14 Length
[0080] 15 Height
[0081] 16 sheet thickness
[0082] 17 External circumference
[0083] 18 Mounting tab
[0084] 19 Circumferential direction
[0085] 20 radial direction
[0086] 21 axial direction
[0087] 22 Joint section
[0088] 23 gas heaters
[0089] 24 First electrode connection 25 Second electrode connection 26 Sheath housing
[0090] 27 catalytically active coating 28 gap
[0091] 29 Opening
Claims
Claims 1. Arrangement (1) comprising at least one metallic disc-shaped honeycomb structure (2) and at least one support structure (3), wherein the at least one disc-shaped honeycomb structure (2) is formed by a plurality of metal foils (4) which form at least one layer package (5) and wherein the metal foils (4) form a plurality of honeycombs (8) within the at least one layer package (5), wherein the at least layer package (5) further comprises a first layer end (6) and a second layer end (7) and is arranged wound or coiled between the layer ends (6, 7) so that the layer package (5) does not contact itself between the layer ends (6, 7), wherein furthermore the first layer end (6) and the second layer end (7) are arranged on a circumferential edge (9) of the honeycomb structure (2) and are each provided with an external contact plate (10, 11) which is otherwise exposed, wherein the at least one support structure (3) is designed in a disc shape and is connected to the metallic honeycomb structure (2) by a plurality of support pins (12), so that a predetermined distance (13) is set between the support structure (3) and the honeycomb structure (2).
2. Arrangement (1) according to claim 1, wherein the contact plates (10, 11) are flush with the layer ends (6, 7) and do not extend over a length (14) and height (15) of the respective layer end (10, 11).
3. Arrangement (1) according to one of the preceding claims, wherein the contact plates (10, 11) are designed with a sheet thickness (16) in the range of 1 to 4 mm.
4. Arrangement (1) according to any one of the preceding claims, wherein the contact plates (10, 11) are arranged on an outer circumference (17) of the honeycomb structure (2) and / or the support structure (3).
5. Arrangement (1) according to any one of the preceding claims, wherein the contact plates (10, 11) are soldered to the layer ends (6, 7).
6. Arrangement (1) according to one of the preceding claims, wherein the support structure (3) has a plurality of fastening tabs (18) which surround the honeycomb structure (2) both in the circumferential direction (19) and in the radial direction (20).
7. Arrangement (1) according to claim 6, wherein the fastening tabs (18) form a hinge section (22) with which a position of the fastening tabs (18) relative to the honeycomb structure (2) can be elastically deformed.
8. Use of an arrangement (1) according to one of the preceding claims for the flexible manufacture of various electrically heated gas heaters (23), wherein the gas heaters (23) in particular have different electrode connections (24, 25) and / or jacket housings (26).
9. Method for manufacturing an electrically heated gas heater (23), comprising at least the following steps: a) Providing a prefabricated arrangement (1) according to any one of the preceding claims; b) Determining an electrical connection configuration and / or an enclosure configuration; c) Inserting the arrangement (1) with the determined connection configuration and / or an enclosure configuration into a jacket housing (26); d) Attaching the at least one support structure (3) to the casing (26); e) Attaching electrode connections (24, 25) to the contact plates (10, 11) of the honeycomb structure (2).
0. Electrically heated gas heater (23) manufactured according to a method according to claim 9, wherein the honeycombs (8) formed by the metal foils are at least partially provided with a catalytically active coating (27) for exhaust gas aftertreatment.