Device, system and method for isolating a component for exhaust gas aftertreatment

Abstract

Component (10) for exhaust gas aftertreatment, with a housing (26) that defines an inner cavity (56) through which exhaust gases can pass, the housing (26) consisting of an inner body (34), an outer body (32) and a space (66) defined between the inner body (34) and the outer body (32), and an insulation package (100) positioned in the room (66), wherein the insulating package (100) consists of insulating material (102) encapsulated in a flexible fabric (104) and an at least partially rigid element (110) whose stiffness is greater than the stiffness of the insulating material (102) and the flexible fabric (104), characterized by that the at least partially rigid element (110) extends over a significant part of the width (W) of the insulation package (100) and thereby substantially prevents bending, curvature or compression of the insulation package (100) in the width direction, so that the insulation package (100) is generally flexible along its length (L) but substantially rigid along its width (W), and that the at least partially rigid element (110) is attached to an outer surface of the flexible fabric (104).

Description

TECHNICAL AREA

[0001] This invention relates to exhaust systems for internal combustion engines, more precisely, to the insulation for components of exhaust aftertreatment systems. BACKGROUND OF THE INVENTION

[0002] Exhaust aftertreatment systems capture exhaust gases produced by an internal combustion engine and subject them to further treatment. Typical exhaust aftertreatment systems consist of various components configured to reduce the level of harmful exhaust emissions. For example, some exhaust aftertreatment systems for diesel-powered internal combustion engines include a particulate filter, a diesel oxidation catalyst, and a selective catalytic reduction (SCR) catalyst. Before being released into the environment, the hot exhaust gases from the engine pass through each of these components. The exhaust aftertreatment components consist of a housing that encloses an internal cavity containing a filter or catalyst for exhaust aftertreatment.When hot exhaust gases pass through the inner cavity, their heat can cause the surface temperature of the housing walls to rise. Due to the potential safety risks associated with high surface temperatures, safety regulations have been established that specify maximum limits for the temperature of the outer surfaces of housings. To comply with these safety regulations, efforts have been made to reduce the temperature of the outer surfaces of exhaust aftertreatment components. In a conventional exhaust aftertreatment system, an insulating layer is wrapped around the outer surface of the component housings.

[0003] In another conventional exhaust aftertreatment system, an insulating layer is installed within a space bounded by an outer and an inner wall of the component housing. This method is particularly useful when the outer surface of the component is used for mounting it to the vehicle and therefore cannot be covered with insulation. The cavity is a fully enclosed chamber that is not directly exposed to the hot exhaust gases as they pass through the component. Furthermore, the outer and inner walls of the component housing are not configured to compress the insulating layer.

[0004] DE 38 20 981 A1 discloses an exhaust gas purification device with a cleaning unit arranged in a metallic housing, wherein at least one elastic mat for mounting and insulating the cleaning unit is arranged between the inner wall of the housing and the outer surface of the cleaning unit, and the mat is wholly or partially surrounded by a covering made of highly heat-resistant material in such a way that essentially no mat discharge reaches the inlet and outlet nozzles.

[0005] US Patent 2006 0 067 860 A1 discloses a double-walled construction for an engine exhaust pipe, wherein a spacer structure defines an insulating annular gap between an inner and an outer pipe and can form a unit with the inner or outer pipe.

[0006] US Patent 2007 O 166 495 A1 discloses an elongated textile protective cover for protecting elongated parts and a method for producing a fabric substrate for it, which has a plurality of thread-like elements that are either woven, knitted or interwoven.

[0007] DE 22 13 540 A discloses a catalyst body for cleaning the exhaust gases of internal combustion engines, consisting of a gas-permeable catalyst support with a large surface area, on which the catalyst material that effects the catalytic reactions is applied. It further discloses a protective shell at least on the circumferential surface of the catalyst body parallel to the flow direction. The protective shell is composed of non-combustible, heat-insulating mineral fibers, reinforcement made of high-temperature-resistant steel components, and a heat-resistant binder in which the first two components are embedded. Suitable steel components for reinforcement include loose, elongated steel pieces or steel shavings. DEPICTION

[0008] The present invention was developed in response to the current state of the art, and in particular to problems and needs of the prior art that could not yet be fully solved with the insulation methods currently available for components of exhaust aftertreatment systems. For this reason, the present invention was developed to provide a device, a system, and a method for insulating components for exhaust aftertreatment that overcomes at least some of the following shortcomings or other deficiencies of insulation methods according to the prior art.

[0009] Winding insulation wrapped around the outside of exhaust aftertreatment components using known methods may cover mounting areas required for attaching the components to a vehicle. Insulation encapsulated in a film, positioned in a chamber bounded by an outer and an inner wall and completely enclosed according to other known methods, does not cover the outside of the component, but at the same time does not provide a sufficient seal to prevent exhaust gases from passing between the insulation and the outer and inner walls.

[0010] Insulation encapsulated in a fabric positioned within the fully enclosed chamber is not exposed to the hot exhaust gases and therefore does not need to seal the chamber. However, adequately sealing the chamber from the effects of the exhaust gases requires other methods such as precision and full welding, which entail additional manufacturing steps and costs. If the fabric-encapsulated insulation is exposed to hot exhaust gases, it will not compress to seal the chamber. Furthermore, without compression, the insulating fiber may migrate from the insulation into the post-treatment component, potentially reducing the component's effectiveness. Additionally, the known fabric-encapsulated insulation is not rigid enough for installation in a chamber designed to compress the insulation as described here.Generally, for the installation of fabric-encapsulated insulation, it is inserted through the chamber in the aftertreatment component. If the chamber is designed to compress the insulation, and the insulation is not sufficiently rigid, it may crumple and prevent movement during insertion into the chamber. For this reason, the present invention was developed to provide a device and system for insulating exhaust aftertreatment components that eliminates at least some of the shortcomings of insulation methods according to the prior art.

[0011] The present invention is defined by the claims. Components according to the invention for exhaust aftertreatment are defined in claims 1 and 11, a manufacturing method according to the invention for them is defined in claim 15, and insulating packages according to the invention for insulating a component for exhaust aftertreatment are defined in claim 24. Preferred embodiments are specified in the respective dependent claims.

[0012] According to a representative embodiment that overcomes one or more shortcomings of the prior art, an exhaust aftertreatment component comprises a housing that defines an inner cavity through which exhaust gases can flow. The housing comprises an inner body, an outer body, and a space defined between the inner and outer bodies. The component also includes an insulating pack positioned within this space. The insulating pack consists of an insulating material encapsulated in a flexible fabric.Furthermore, the insulation package consists of an at least partially rigid element whose stiffness is greater than the stiffness of the insulating material and the flexible fabric, and which extends over a substantial part of the width of the insulation package, thereby substantially preventing bending, curvature, or compression of the insulation package in the lateral direction, so that the insulation package is generally flexible along its length but substantially rigid along its width, and the at least partially rigid element is attached to an outer surface of the flexible fabric.

[0013] In one embodiment, the insulating package has a length that extends substantially at right angles to an axis of the substantially cylindrical housing. The stiffness of the at least partially rigid element, the insulating material, and the flexible fabric is an axial stiffness that lies substantially parallel to the axis of the housing.

[0014] According to some embodiments, the at least partially rigid element is a plate. This element can extend laterally from a first side of the insulation package to a second side. In one embodiment, the element is designed to burn away during operation of the component.

[0015] In certain embodiments, the outer body of the component compresses the insulating pack against the inner body in a direction substantially perpendicular to an axis of the component. In some embodiments, the insulating pack also forms a seal with the inner and outer bodies to prevent exhaust gases from passing between the insulating pack and the inner and outer bodies.

[0016] According to some embodiments, the inner body can be inserted into the outer body. The inner body can generally have a cylindrical shape and consists of an inner wall and two spaced-apart side walls extending radially outward from the inner wall. The space described above can be confined between the outer body, the inner wall, and the two side walls of the inner body. A gap can be confined between at least one of the two side walls of the inner body and the outer body. The flexible fabric of the insulating pack can come into contact with the hot exhaust gases passing through the gap.

[0017] In another embodiment, the exhaust aftertreatment component consists of an outer body, an inner body arranged at a distance from the outer body, a chamber bounded between the outer and inner bodies, and an insulating pack positioned in the chamber. The insulating pack consists of an insulating material encapsulated in a flexible fabric and has a rigid element that extends over a significant portion of the width of the insulating pack, thereby substantially preventing bending, curvature, or compression of the insulating pack in the lateral direction. Thus, the insulating pack is generally flexible along its length but substantially rigid along its width. To compress the insulating pack against the inner body, the outer body exerts a compressive force on the insulating pack.

[0018] According to some embodiments, the insulating pack is deformable under compressive force to create a seal between the outer and inner bodies. The compressive force can be a radial force acting at a right angle to the central axis of the component. The insulating pack can contain a rigid element whose axial stiffness is greater than the axial stiffness of the insulating pack and the flexible fabric. The compressive force can be a radial force acting at a right angle to the central axis of the component; the insulating material can have an axial stiffness exceeding its radial stiffness.

[0019] According to a further embodiment, a method for manufacturing a component for exhaust aftertreatment comprises the provision of a first body comprising a first inner surface and a first outer surface. The first inner surface defines a first inner cavity. The method also comprises the provision of a second body comprising a second inner surface and a second outer surface. The second inner surface defines a second inner cavity.The method also includes positioning an insulating pack around the first body along the first outer surface. The insulating pack consists of insulating material encased in a fabric and includes an axially rigid element extending over a substantial portion of the pack's width, thus substantially preventing bending, curvature, or compression of the insulating pack in the lateral direction. Therefore, the insulating pack is generally flexible along its length but essentially rigid along its width. Furthermore, the method consists of inserting the first body into the second interior space of the second body such that the insulating pack is positioned between the first outer surface and the second inner surface. Additionally, the method consists of compressing the insulating pack with the second body while the first body is being inserted into the second interior space of the second body.

[0020] In some embodiments, the first body and the second body are generally cylindrical, while the compression of the insulating pack consists of radial inward compression of the insulating pack. Inserting the first body into the second interior space of the second body can involve inserting the first body into the second interior space of the second body in a substantially axial direction. The method can further consist of resisting the axial compression of the insulating pack while the first body is being inserted into the second interior space of the second body. In certain embodiments, resistance to axial compression is provided by a rigid element coupled to the insulating pack.In other embodiments, the insulating material of the insulating package is axially rigid; the resistance to axial compression is made possible by the axial stiffness of the insulating material.

[0021] In some embodiments, the insulating pack has a first thickness before the first body is inserted into the second interior space of the second body. This first thickness is greater than the maximum distance between the first outer surface and the second inner surface after the first body has been inserted into the second interior space of the second body. The compression of the insulating pack can then involve reducing its thickness from the first thickness to a second thickness approximately equal to the maximum distance between the first outer surface and the second inner surface.

[0022] In certain embodiments, the method further comprises deforming the insulating package into a sealed engagement with the first outer surface and the second inner surface. In other embodiments, the method comprises sealing the first outer surface and the second inner surface with the insulating package.

[0023] According to another embodiment, an insulating package for insulating an exhaust aftertreatment component along the interior of the component comprises an insulating material and a flexible fabric encapsulating the insulating material, as well as an axial stabilizer attached to the insulating material and / or the flexible fabric, the stabilizer having a stiffness greater than that of the insulating material and the flexible fabric, wherein the axial stabilizer further comprises a metal foil, or the insulating material has at least two insulating layers and the axial stabilizer comprises an adhesive bonding the layers of the insulating material together. The component defines a central axis. Relative to the central axis, the insulating package is radially compressible and axially essentially incompressible. The component may include auxiliary means to achieve radial stiffness.

[0024] References throughout this specification to features, advantages, or similar expressions do not imply that all features or advantages that can be implemented with the present invention are or should be present in one and the same embodiment of the invention. Rather, expressions relating to features and advantages are intended to mean that certain individual features, advantages, or characteristics described in connection with an embodiment are present in at least one embodiment of the present invention. A discussion of features and advantages or similar statements in this specification may, but need not, refer to the same embodiment.

[0025] The described features, advantages, and characteristics of the invention can be suitably combined in one or more embodiments. Experts will recognize that the invention can also be used without one or more of the specific features and advantages of a particular embodiment. In other cases, additional features and advantages may be identified in certain embodiments that may not be present in all embodiments of the invention. These features and advantages of the present invention will become more apparent from the following description and the accompanying claims, or can be discerned from the practical implementation of the invention described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] To better understand the advantages of the subject matter, a more detailed description of the subject matter briefly described above is provided by reference to specific embodiments illustrated in the accompanying drawings. It should be noted that these drawings only depict typical embodiments of the subject matter and are therefore not to be considered as limiting the scope of application. The subject matter is described and explained with additional accuracy and detail through the use of these drawings; these drawings show: Fig. 1 a perspective view of a component for exhaust gas aftertreatment according to an embodiment of the invention, Fig. 2 a perspective sectional view of the component for exhaust gas aftertreatment of Fig. 1, Fig. 3 A side cross-sectional exploded view of the component for exhaust aftertreatment of Fig. 1, Fig. 4 A side cross-sectional exploded view of the component for exhaust aftertreatment of Fig. 1 with an insulating package around an inner body, Fig. 5 a side sectional view of the component for exhaust gas aftertreatment of Fig. 1, Fig. 6 a perspective view of an insulating package according to an embodiment of the invention, Fig. 7 a side sectional view of the component for exhaust aftertreatment of Fig. 1. Showing the installation of the insulation package, Fig. 8 a lateral sectional view of a component for exhaust gas aftertreatment according to another embodiment of the invention showing an insulating package without an axial stabilizer, Fig. 9 a lateral sectional view of a component for exhaust gas aftertreatment with several insulation packages according to another embodiment of the invention, and Fig. 10 a lateral sectional view of a component for exhaust gas aftertreatment with an insulation package comprising an axially rigid insulating material according to another embodiment of the invention. DETAILED DESCRIPTION

[0027] Throughout this entire specification, “an embodiment”, “a single embodiment”, or similar terms mean that a feature, structure, or characteristic described in connection with the embodiment is present in at least one embodiment of the invention. Throughout this entire specification, the expression “in an embodiment”, “in a single embodiment”, or a similar expression may, but does not necessarily, refer to one and the same embodiment.

[0028] The described features, structures, or characteristics of the invention can be suitably combined in one or more embodiments. Numerous specific details are given in the following description to facilitate a thorough understanding of the embodiments of the invention. However, experts in the field will recognize that the invention can also be used without one or more of these specific details or with other methods, components, materials, etc. In other cases, known structures, materials, or modes of operation are not shown or described in detail to avoid obscuring other aspects of the invention.

[0029] This document describes various embodiments of an insulating package for insulating different components of an exhaust aftertreatment system connected to an internal combustion engine. In one embodiment, the insulating package is fitted along the inner surface of a component in such a way that it does not interfere with the mounting areas on the outer surface of the component. The insulating package may have a flexible fabric in which the insulating material is encapsulated. The insulating package can be radially compressed to form a seal between the insulating package and the component and to prevent the migration of insulating fibers. To significantly reduce compression in the axial direction, the insulating package may include an axial stabilizer or a rigid element. The axial stabilizer allows the insulating package to be installed in the component without undesirable crumpling of the package.The fabric can also be a high-temperature fabric capable of withstanding the high temperatures of the exhaust gases flowing through the component. In some embodiments, the flexible fabric can therefore be in direct contact with the exhaust gases.

[0030] In a Fig. In the specific embodiment shown in Figure 1, a component 10 of an exhaust aftertreatment system (not shown) comprises a first particulate filter section 12, an oxidation catalyst section 14 downstream of the first particulate filter section 12, and a second particulate filter section 16 downstream of the oxidation catalyst section. The component 10 includes an exhaust inlet 22 for receiving the exhaust gases 18 and an exhaust outlet 24 for the exhaust gases 20 exiting the component. The exhaust inlet 22 and the outlet 24 are coupled to a housing 26 of the component 10. The housing extends from a first end 28 to a second end 30. The exhaust gases 18 entering the component 10 through the exhaust inlet 22 pass through the first particulate filter section 12, the oxidation catalyst section 14 and a second particulate filter section 16 before leaving the component through the exhaust outlet 24.In some application examples, the second particle filter section 16 is essentially a mirror image of the first particle section 12. Therefore, the general characteristics of the first particle section 12, described in more detail below, may apply equally to the second particle section 16.

[0031] In Fig. The housing 26 comprises an outer body 32 and an inner body 34. The outer body 32 comprises a generally cylindrical tubular element extending approximately from the first end 28 of the housing 26 to approximately the second end 30 of the housing. The outer body 32 further comprises an outer surface 36 and an opposite inner surface 38. The outer body 32 has a first outer diameter D1 along the first filter section 12 (see Fig. 4) The inner surface 38 of the outer body 32 defines a first inner cavity 40. The inner cavity 40 along the first filter section 12 has a second diameter D2 (see Fig. 4) The oxidation catalyst section 14 comprises an oxidation catalyst 42 positioned in the first inner cavity 40 and may have an outer insulating layer 44 extending over the outer surface 36. The filter section 12 comprises an annular stop 46 attached to the inner surface 38 of the outer body 32 at a location between the oxidation catalyst 42 and the first end 28. The stop 46 extends radially inward from the inner surface 38 toward a central axis 48 of the component 10 (see Fig. 3) and limits an opening 50 through which the exhaust gases can flow into the oxidation catalyst section 14.

[0032] The inner body 34 comprises a generally cylindrical tubular element that has an outer surface 52 and an opposing inner surface 54 (see e.g. Fig. 3) The inner surface 54 defines a second inner cavity 56 into which filter medium (not shown) can be introduced. The filter medium usually comprises a cylindrical filter having channels of various shapes through which the exhaust gases flow. As the exhaust gases pass from one channel to another, particulate matter is filtered from the exhaust and deposited on the walls of the channels. Finally, the deposited particulate matter is burned during a filter regeneration process. In the illustrated embodiment, the filter medium has been removed to allow the features of the inner body 34 to be shown more clearly.

[0033] In the Fig. 2 and Fig. The inner body 34 is generally U-shaped in cross-section, with an inner wall 60 positioned between two spaced-apart side walls 62, 64, which extend substantially radially outwards (e.g., substantially at right angles) from the inner wall 60 away from the central axis 48. The space bounded by the inner wall 60 and the side walls 62, 64 forms an annular space 66 that accommodates the insulating package. The inner body 34 is attached to the first end section 70 of the housing 26. The first end section 70 bounds the first end 28 of the housing 26; the exhaust inlet 22 is coupled to the first end section 70. The first end section 70 comprises an outer shell 72, an inner shell 74, and insulating material 76 positioned between the outer shell and the inner shell. The inner body 34 is attached to the end section 70 by coupling the side wall 62 to the inner shell 74.The side wall 62 can be attached to the inner shell 74 by any of the various fastening methods known in the art, such as welding, gluing, adhesion, or fastening with brackets. Preferably, the inner body 34 is attached to the inner shell 74 such that the inner wall 60 of the inner body 34 extends substantially at a right angle away from the inner shell (e.g., substantially parallel to the central axis 48).

[0034] In Fig. 2 A space or chamber 78 is defined between the outer body 32 and the inner body 34. Generally, the chamber 78 comprises the insulation receiving space 66 surrounded by the inner surface 38 of the outer body 32. In the illustrated embodiment, the chamber 78 is enclosed by the contact between the outer body 32, the inner body 34, the stop 46, and the first end section 70. In some application examples, such as in connection with Fig. As described in more detail below, chamber 78 is closed, although a gap or gaps exist between the inner and outer bodies 32, 34. The contact between the outer body 32, the inner body 34, the stop 46, and the first end section 70 of the component 10 does not necessarily constitute a seal that would prevent the exhaust gases from flowing from one sub-section to another. In some application examples, the sub-sections can be fully welded together to form a tight seal between them. However, full welding can be costly and time-consuming, which would burden the production process. To avoid such a burden on the production process, as described in more detail below, in some application examples the sub-sections are held in contact with each other by friction, slight pressure, or partial welding.While these fastening methods reduce production time and costs, the interface between the sub-areas may not provide a seal that would prevent bypassing by exhaust gases.

[0035] The outer shell 72 of the first end section 70 includes a lip portion 80 that extends substantially at a right angle away from the first end section 28 of the housing 26 and substantially parallel to the central axis 48. The lip portion 80 delineates a cylindrically shaped space having a third diameter D3. Similarly, the inner shell 74 of the first end section 70 includes a lip portion 82 that extends downstream from the first end 28. The lip portion 82 has a fourth maximum inner diameter D4 and a maximum outer diameter approximately equal to the third diameter D3. The fourth diameter D4 of the lip portion 82 is only slightly smaller than the first outer diameter D1 of the outer body 32. The lip portion 82 of the inner shell 74 can extend from the first end 28 in a radially inward direction toward the central axis 48 and has a radially outward-curving tip.The cylindrically shaped space bounded by the lip section 80 of the outer shell 72 accommodates part of the insulation 76 and part of the inner shell 74 such that the lip section 80 at least partially surrounds the lip section 82 of the inner shell 74. The lip section 80 can be attached to the lip section 82 using various fastening methods, for example, by welding.

[0036] Although the illustrated component is a combination of a particulate filter and an oxidation catalyst, it can be any of the various components used in exhaust aftertreatment systems designed to separate or reduce harmful particles or emissions from the exhaust gases produced by an internal combustion engine. For example, in some application examples, the component may consist of a particulate filter, an oxidation catalyst, a selective catalytic reduction (SCR) catalyst, or an ammonia oxidation catalyst. Furthermore, although the component 10 is shown in the exemplary embodiment as having a generally cylindrical cross-section, it can have any cross-sectional shape other than cylindrical, such as rectangular, egg-shaped, or elliptical shapes.

[0037] As in Fig. As shown in Figure 2, the component 10 comprises an insulating package 100 positioned along an interior of the component. Generally, the insulating package 100 is used to insulate the outer contact surface of an exhaust aftertreatment component from the hot exhaust gases flowing through the component. Fig. 2 and Fig. 6. The insulating package 100 comprises a sheet of insulating material 102 encapsulated in a fabric 104. The insulating package 100 is generally flexible along its length L, but rigid along its width W. For example, the insulating package 100, as shown in Fig. 3 and Fig. The insulating material 104, as shown in Figure 6, is bent along its length L and forms a generally curved or ring-shaped form. The insulating material 102 can be one of the many insulating materials known in the art, made from any of the various insulating materials such as carbon, silica, glass fiber, cellulose, polyurethane, polystyrene, or ceramic. In some application examples, the insulating material 102 comprises a variety of insulating fibers made from the insulating materials. Preferably, the fabric 104 is at least partially flexible, temperature-resistant to high temperatures, e.g., above 1,800°F, and substantially non-flammable. In certain application examples, the fabric 104 is less rigid than the insulating material 102. As shown in Figure 6, the insulating material 104 is made from the insulating material 102. Fig. As shown in Figure 6, in one embodiment one or more pieces of fabric 104 are placed over the entire insulating material 102, and the fabric encapsulates the material by means of seams 106 within the fabric, e.g., by holding the fabric together along each edge of the material. In other embodiments, the seams are achieved by adhesives or other bonding methods.

[0038] In its straight state, the insulating pack 100 can generally assume a rectangular shape, as illustrated in the exemplary embodiment. Alternatively, the insulating pack 100 can have any shape suitable for the specific application or the component used. For example, the edges of the insulating pack can have grooves, holes, or curves so that it can be applied around interfering structures or geometric features of the post-treatment component. Furthermore, as shown in Fig. 6 shown, openings such as opening 108 in the insulating package 100 for receiving component devices such as sensors or sensor connections, e.g. sensor connection 83 (see Fig. 3 - 5) are provided.

[0039] As in Fig. As shown in Figure 2, the insulating package 100 includes an axial stabilizer 110 that extends over a substantial part of the width of the insulating package. The insulating package 100 is designed to be radially compressible and axially essentially incompressible. For it to be essentially axially incompressible, the insulating package 100 need not be completely incompressible axially, but may exhibit an insignificant or minor degree of compressibility. In one application example, "essentially axially incompressible" is defined as allowing that degree of compressibility which does not cause the insulating package to crumple against the outer body 32 during assembly of the component 10 (see Figure 2). Fig. 8 below).

[0040] The axial stabilizer 110 essentially prevents bending, curvature, or compression along the width axis of the insulation pack. As described in more detail below, the width of the insulation, after its installation in the filter section 12, lies essentially parallel to the central axis 48 of the component 10. Therefore, the stabilizer 110 is an axial stabilizer because it counteracts bending, curvature, or compression of the insulation pack 100 in the axial direction, i.e., in a direction essentially parallel to the central axis 48 of the component 10. In general, the axial stabilizer 110 has a stiffness in the axial direction that is higher than the stiffness of the insulating material 102 and the fabric 104 in the axial direction. The axial stabilizer 110 can consist of any device or any part or element that is at least partially stiff in the axial direction.In certain application examples, the axial stabilizer 110 is a film, a plate, a rod, or a binding device that occupies a relatively small proportion, e.g., less than 50% of the thickness of the insulating package 100. The axial stabilizer 110 can be flat or corrugated, for example, also consisting of grooves. The axial stabilizer can be made of any material that is such that it withstands extreme temperatures or is flammable above certain temperature thresholds, for example, metal, cardboard, flammable chemicals, plastic, adhesives (e.g., binders), or, as described in more detail below, the insulating material itself.

[0041] As in Fig. As shown in Figure 2, the axial stabilizer 110 is embedded in the insulating material 102 and extends from the upstream side of the insulating pack to a downstream side of the insulating pack. For example, the axial stabilizer 110 can consist of a metal foil arranged between two insulating layers. Similarly, the axial stabilizer 110 can consist of a hardened adhesive or bonding agent applied between two insulating layers to bind the layers together. Alternatively, the axial stabilizer 110 can be positioned between the insulating material 102 and the fabric 104. In yet other application examples, the axial stabilizer 110, for example, a cardboard stabilizer designed to burn away during operation of the component 10, is attached to the outside of the insulating pack 100. The axial stabilizer 110 can be attached to the insulating material 102 and / or the fabric 104.Alternatively, the axial stabilizer 110 can be a floating component, i.e., it can be attached neither to the means 102 nor to the fabric 104.

[0042] In Fig. 3. The outer body 32, the end section 70, the inner body 34, and the insulating package 100 can be assembled to form the component 10. In Fig. In 4, the insulating package 100 is wrapped around the inner body 34 in the receiving space 66. The inner diameter of the inner body 34 plus the thickness of the insulating package 100 defines a fifth diameter D5.

[0043] The fifth diameter D5 is larger than the second diameter D2 of the inner cavity 40 of the outer body 32. The assembly, consisting of end section 70, inner body 34, and insulating package 100, is inserted into the inner cavity 40 of the outer body 32 such that the outer body 32 surrounds the inner body 34; the insulating package 100 is positioned in the chamber 78 between the inner body and the outer body (see Fig. 5). In Fig. 7. When the inner body 34 is inserted into the outer body 32, the insulating pack 100 is inserted into the chamber 78, for example, stuffed in. In other words, since the diameter D5 of the inner body 34 combined with the insulating pack 100 is larger than the diameter D2 of the inner space 40 of the outer body 32, the wall of the outer body touches the insulating pack when the inner body 34 is inserted into the outer body 32 and compresses it radially. In this way, the insulating pack 100 is held in a state of compression between the outer and inner bodies 32, 34 during use of the component 10. As in Fig. As shown in Figure 7, the insulating package 100 has a first thickness T1 in its uncompressed state before being stuffed into the chamber 78 and a smaller second thickness T2 in its radially compressed state after being stuffed into the chamber.

[0044] When the insulating package 100 is inserted into the chamber 78 in an axial direction, as indicated by the direction arrow 120, the axial stabilizer 110 counteracts the axial compression of the insulating package. Fig. Figure 8 shows an insulating pack 130, similar to the insulating pack 100 but without the axial stabilizer 110, as it is inserted or stuffed into the chamber 78. Since the insulating pack 130 is not axially rigid when inserted into the chamber 78, it is axially compressed and crumples or accumulates at the point of contact with the outer body 32. The accumulation 132 at the entry point into the chamber 78 restricts or prevents further insertion of the insulating pack 130 into the chamber. Without the application of tooling or additional production steps that would hinder the production process, the insulating pack 130 could not be fully inserted into the chamber 78 due to the resistance caused by the accumulation 132.The resistance to axial compression provided by the axial stabilizer 110 reduces the accumulation at the entry point into the chamber 78 and makes it possible to fully introduce the insulating package 100 into the chamber without significant difficulties caused by the resistance or the use of external tools or procedures.

[0045] During radial compression of the insulating pack 100, the flexible fabric 104 conforms to the walls of the outer body 32, the inner body 34, and, in some cases, the stop 46, which delimit the chamber 78. For example, it deforms against these walls and forms a seal between the insulating pack and the walls. The compression of the insulating pack 100 maintains the sealing interaction between the walls. The seal restricts the bypass of exhaust gases, i.e., the passage of exhaust gases between the insulating pack 100 and the walls of the outer and inner bodies 32, 34; in some applications, it prevents this bypass entirely. In this way, a seal is achieved to prevent the escape of exhaust gases at those points where there is wall-to-wall contact (e.g., contact between the stop 46 and the inner body 34) or slight welds (e.g.,Welds at the interface of inner body 34 and inner shell 74 or between outer body 32 and stop) do not provide sufficient sealing against the escape of exhaust gases.

[0046] Furthermore, in some embodiments, there may be no wall-to-wall contact or welds between the outer body, inner body, and stop, so the chamber is not completely enclosed. For example, as in Fig. Figure 9 shows a gap 138 between an outer body 142 and an inner body 144 of a component 140. The component 140 is similar to the component 10, except that the inner body 144 has a second insulating package receiving area 146 adjacent to a first insulating package receiving area 148. The inner body 144 is designed to receive the two insulating packages 150, 152 side by side in the first and second receiving areas 146 and 148, respectively. The insulating packages 150, 152 each comprise a flexible fabric 170, 174, which encapsulates an insulating material 172, 176, as well as an axial stabilizer 154 and 156, respectively. The wall 160 bounding the first receiving area 148 is attached to an annular mounting clamp 162 similar to the stop 46. The mounting bracket 162 is attached to the inner body 144.The second receiving area 146 is bounded by a wall 164, which is attached to the mounting bracket 162 and extends substantially at a right angle away from it. The wall 164 terminates at a downstream end 166, which is positioned at such a distance from the outer body 142 that the gap 138 between the downstream end and the outer body is limited.

[0047] Component 140 is assembled in a similar manner to component 10, with the insulating packs 150 and 152 wrapped around the inner body 144, and the combination of inner body 144 and insulating packs 150 and 152 being inserted into the outer body 142. As the inner body 144 is inserted into the outer body 142, the outer body 142 radially compresses both insulating packs 150 and 152. This radial compression causes the fabric to form seals between the outer and inner bodies 142 and 144 and the corresponding insulating packs. Therefore, the seal formed by the insulating package 150 prevents exhaust gases from escaping into the space between the insulating package and the outer body, although the exhaust gases have the possibility of flowing through the gap 138 and coming into contact with the insulating package 150 and a small area of ​​the outer body 142.Although the gap 138 between the end 166 of the inner body 144 and the outer body 142 is limited, other embodiments may have one or more gaps at various other locations. Regardless of the number or size of the gaps, their presence has no negative impact on the insulating properties of the insulating package due to its ability to form a seal when compressed. Since the tight tolerances and high dimensional accuracy typically required to prevent gaps are not necessary for sealing the insulating chambers, manufacturing and assembly costs can be reduced.

[0048] In Fig.Figure 10 and a further embodiment show part of a component for exhaust aftertreatment 200. Similar to component 10, component 200 comprises an outer body 202, an inner body 204, and a first end section 206. The inner body 204 includes an outer support surface 208 that defines an insulating package receiving space 210. The component 200 includes an insulating package 212, which is wound around a receiving space and inserted into the outer body 202 in a manner similar to that described above. Upon insertion of the insulating package 212 into the outer body 202, it is radially compressed by the outer body 202. The insulating package 212 comprises an insulating medium 214 encapsulated by a fabric layer 216. The radial compression of the insulating layer causes the fabric layer 216 to conform to the adjacent surfaces and form a seal against the escape of exhaust gases.In contrast to the insulation package 100 described above, the insulation package 212 does not include a separate axial stabilizing element. Rather, the insulating material 214 itself is designed to be radially compressible and axially incompressible so that it resists crumpling when the insulation package 212 is installed in the outer body 202, as described above. In certain application examples, the insulating material 214 comprises a plurality of at least partially rigid insulating fibers aligned in the axial direction. In this way, the insulating material 214 is rigid in the axial direction but compressible or flexible in the radial direction.

[0049] The present invention can be implemented in other specific forms. The described embodiments are to be considered illustrative in every respect, but not limiting. The scope of the invention is therefore not defined by the preceding description, but rather by the accompanying claims.

Claims

[1] Component (10) for exhaust aftertreatment, with a housing (26) that defines an inner cavity (56) through which exhaust gases can pass, the housing (26) consisting of an inner body (34), an outer body (32) and a space (66) defined between the inner body (34) and the outer body (32), and an insulation package (100) positioned in the room (66), wherein the insulating package (100) consists of insulating material (102) encapsulated in a flexible fabric (104) and an at least partially rigid element (110) whose stiffness is greater than the stiffness of the insulating material (102) and the flexible fabric (104), characterized by , that the at least partially rigid element (110) extends over a significant part of the width (W) of the insulation package (100) and thereby substantially prevents bending, curvature or compression of the insulation package (100) in the width direction, so that the insulation package (100) is generally flexible along its length (L) but substantially rigid along its width (W), and that the at least partially rigid element (110) is attached to an outer surface of the flexible fabric (104). [2] Component (10) for exhaust gas aftertreatment according to claim 1, the housing is essentially cylindrical, wherein the length (L) extends substantially at a right angle to the axis (48) of the housing (26) and wherein the stiffness of the at least partially rigid element (110), the insulating medium (102) and the flexible fabric (104) form an axial stiffness lying essentially parallel to the axis (48) of the housing (26). [3] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the at least partially rigid element (110) has a plate. [4] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the at least partially rigid element (110) extends laterally from a first side of the insulation package (100) to a second side of the insulation package (100). [5] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the outer body (32) compresses the insulating package (100) against the inner body (34) in a direction that is substantially perpendicular to the axis (48) of the component (10). [6] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the insulating package (100) forms a seal with the inner body (34) and the outer body (32) to prevent the passage of exhaust gases between the insulating package (100) and the inner body (34) and the outer body (32). [7] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the inner body (34) is inserted into the outer body (32). [8] Component (10) for exhaust gas aftertreatment according to claim 7, characterized by , that the inner body (34) has a generally cylindrical shape and consists of an inner wall (52) and two side walls (62, 64) arranged at a distance from each other, which extend radially outwards from the inner wall (52). [9] Component (10) for exhaust gas aftertreatment according to claim 8, characterized by, that the space between the outer body (32), the inner wall (52) and the two side walls (62, 64) of the inner body (34) is limited, that a gap is formed between at least one of the two side walls (62, 64) of the inner body (34) and the outer body (32), and that the flexible fabric (104) of the insulating package (100) is in contact with the hot exhaust gases passing through the gap. [10] Component (10) for exhaust gas aftertreatment according to claim 1, characterized by , that the at least partially rigid element (110) is designed in such a way that it burns up during the operation of the component (10). [11] Component (10) for exhaust aftertreatment, with an external body (32), an inner body (34) arranged at a distance from the outer body (32), a chamber (66) bounded between the outer body (32) and the inner body (34), and an insulating package (100) positioned in the chamber (66), wherein the insulating package (100) consists of an insulating medium (102) encapsulated in a flexible fabric (104), characterized by , that the insulating package (100) further comprises a rigid element (110) which extends over a significant part of the width (W) of the insulating package (100) and thereby substantially prevents bending, curvature or compression of the insulating package (100) in the width direction, so that the insulating package (100) is generally flexible along its length (L) but substantially rigid along its width (W), and that the outer body (32) exerts a pressure force on the insulating package (100) to compress the insulating package (100) against the inner body (34). [12] Component (10) for exhaust gas aftertreatment according to claim 11, characterized by, that the insulating package (100) is deformable under the compressive force in order to create a seal between the outer body (32) and the inner body (34). [13] Component (10) for exhaust gas aftertreatment according to claim 12, characterized by , that the compressive force is a radial compressive force acting at a right angle to the central axis (48) of the component (10) and the rigid element (110) has an axial stiffness exceeding the stiffness of the insulating package (100) and the flexible fabric (104). [14] Component (10) for exhaust gas aftertreatment according to claim 12, characterized by , that the compressive force is a radial compressive force acting at a right angle to the central axis (48) of the component (10) and the insulating material (102) has an axial stiffness exceeding the radial stiffness. [15] Method for manufacturing a component (10) for exhaust gas aftertreatment, comprising the following features: Providing a first body (34) comprising a first inner surface (54) defining a first inner cavity (56) and a first outer surface (52), Providing a second body (32) comprising a second inner surface (38) defining a second inner cavity (40), and a second outer surface (36), Positioning an insulating package (100) around the first body (34) along the first outer surface (52), the insulating package (100) comprising an insulating medium (102) covered with a fabric (104), and further comprising an axially rigid element (110) extending over a substantial part of the width (W) of the insulating package (100) and thereby substantially preventing bending, curvature or compression of the insulating package (100) in the width direction (W), so that the insulating package (100) is generally flexible along its length (L) but substantially rigid along its width (W), Inserting the first body (34) into the second inner cavity (40) of the second body (32) such that the insulating package (100) is positioned between the first outer surface (52) and the second inner surface (38), and Compressing the insulating package (100) with the second body (32) while the first body (34) is inserted into the second inner cavity (40) of the second body (32). [16] Method according to claim 15, characterized by , that the first body (34) and the second body (32) are generally cylindrical, wherein the compression of the insulating package (100) comprises a radially inward compression of the insulating package (100). [17] Method according to claim 16, characterized by, that the insertion of the first body (34) into the second inner cavity (40) of the second body (32) comprises the insertion of the first body (34) into the second inner cavity (40) of the second body (32) in a substantially axial direction. [18] Method according to claim 16, characterized by , that the method further comprises resisting axial compression of the insulating package (100) while the first body (34) is inserted into the second inner cavity (40) of the second body (32). [19] Method according to claim 18, characterized by , that the resistance to axial compression is made possible by the rigid element (110) coupled to the insulating package (100). [20] Method according to claim 18, characterized by , that the insulating medium (102) of the insulating package (100) is axially rigid and that the resistance to axial compression is enabled by the axial stiffness of the insulating medium (102). [21] Method according to claim 15, characterized by , that the insulating package (100) has a first thickness (T1) before the insertion of the first body (34) into the second inner cavity (40) of the second body (32), wherein the first thickness (T1) is greater than the greatest distance between the first outer surface (52) and the second inner surface (38) after the insertion of the first body (34) into the second inner cavity (40) of the second body (32), and that the compression of the insulating package (100) comprises reducing the thickness of the insulating package (100) from the first thickness (T1) to a second thickness (T2) approximately corresponding to the greatest distance between the first outer surface (52) and the second inner surface (38). [22] Method according to claim 15, characterized by, that the method further comprises deforming the insulating package (100) into a sealed engagement with the first outer surface (52) and the second inner surface (38). [23] Method according to claim 15, characterized by , that the method further comprises sealing the first outer surface (52) and the second inner surface (38) with the insulating package (100). [24] Insulation package (100) for insulating a component (10) for exhaust aftertreatment along the interior of the component (10), wherein the component (10) defines a central axis (48) and the insulation package (100) has: an insulating material (102), a flexible fabric (104) encapsulating the insulating material (102) and an axial stabilizer (110) attached to the insulating material (102) and / or to the flexible fabric (104), characterized by , that the axial stabilizer (110) has a stiffness that is greater than the stiffness of the insulating material (102) and the flexible fabric (104), that the insulating package (100) is radially compressible and axially essentially incompressible, and that either the axial stabilizer (110) has a metal foil, or the insulating material (102) has at least two insulating layers and The axial stabilizer (110) comprises an adhesive that bonds the layers of the insulating material (102) together. [25] Insulation package according to claim 24, characterized by , that the axial stabilizer (110) has a metal foil. [26] Insulation package according to claim 24, characterized by that the insulating material (102) has at least two insulating layers and that the axial stabilizer (110) comprises an adhesive that bonds the layers of the insulating material (102) together.

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