Sound insulation element for the front wall of a vehicle body and load-bearing element for such a sound insulation element

Abstract

The sound-insulating element for a vehicle body front wall, which is arranged between a passenger compartment and an engine compartment, is provided with a composite component having a plastic carrier layer (16) and an acoustic absorption layer (18) connected thereto. The composite component has at least one first channel opening. When observed in its installed state, the composite component has a front side facing the passenger compartment and formed by the outer side of the plastic carrier layer (16), and a rear side leaning against the front wall and formed by the outer side of the acoustic absorption layer (18) facing away from the plastic carrier layer (16). At least one pressing projection (72) projects from the plastic carrier layer (16) at the hole edge of the carrier layer hole and / or offset from the hole edge of the plastic carrier layer (16) on the outer side facing away from the plastic carrier layer (16) and thus facing the inner side of the acoustic absorption layer (18). The pressing projection (72) is embedded in the acoustic absorption material of the acoustic absorption layer (18), and its free end facing away from the plastic carrier layer (16) is substantially aligned with the outer side of the acoustic absorption layer (18) facing away from the plastic carrier layer (16).

Description

[0001] This patent application claims the priority of German Patent Application No. 10 2018 132726.9 filed on December 18, 2018, the content of which is incorporated herein by reference into the subject matter of this patent application. Field of the Invention

[0002] The present invention relates to a sound insulation element for a body front wall that separates a passenger compartment from an engine compartment. Furthermore, the present invention relates to a load-bearing element for a sound insulation composite component arranged on the body front wall. Background Art

[0003] It is well known to arrange sound insulation elements on the inner side of the body front wall, i.e., on the inner side of the wall between the passenger compartment and the engine compartment of the vehicle body. As examples of such front wall barrier materials, reference is made to WO-A-2018 / 192858, US-A-2006 / 0091699, or DE-A-37 33 284.

[0004] Such sound insulation elements have a sandwich structure that has a plastic carrier layer, also known as a heavy layer, and a sound-absorbing layer molded onto the plastic carrier layer and made of a sound-absorbing material, in particular a PUR foam material. The body front wall has a plurality of passages for pipelines, ducts, or components. Accordingly, the sound insulation element is also provided with through holes, which are usually aligned with the passages in the front wall. Depending on the type of elements passing through the sound insulation element and through the front wall, it is necessary to protect it from mechanical damage (wear protection). One possible measure to achieve such protection is to foam around the hole edges of the passage openings of the sound insulation element or to surround it with a sound-absorbing material.

[0005] The sound-absorbing material is usually molded onto the plastic carrier layer in a specially designed molding tool (usually a foaming tool) into which the plastic carrier layer is inserted. The plastic carrier layer has been previously produced in another molding tool provided for this purpose. In the region of the hole edges where at least part of the plastic carrier layer is embedded by the sound-absorbing material, the sound-absorbing material must be able to at least partially extend into the carrier layer holes. To some extent, the sound-absorbing material should surround the hole edges on both sides of the plastic carrier layer. In both cases, this causes the plastic carrier layer to "float" within the molding tool into which it is inserted during the manufacturing process, which results in unsatisfactory manufacturing results. To avoid this, the corresponding molding tool for molding the sound-absorbing material onto the plastic carrier layer has pressing pins that press the plastic carrier layer along the hole edges that are at least partially surrounded by the sound-absorbing material. Such molding tool pressing pins increase the manufacturing cost of the molding tool and complicate the cleaning process, which in principle becomes increasingly difficult to perform. In addition, the sound-absorbing layer formed with such a molding tool has cavities caused by the pressing pins, which is acoustically disadvantageous.

[0006] It is known from DE-A-10 2013 006 300 that the core of an appliance handle surrounded by plastic can be positioned in the center of a molding tool by means of spacer pins protruding from the core in all directions. This method is not applicable to a two-component part in which a plastic component is only equipped with a second plastic component on one side.

[0007] DE-C-198 33 098 discloses a method for manufacturing a padded article having a core and a padded cover surrounding it on all sides. Summary of the Invention

[0008] The object of the present invention is to provide a sound-insulating element for a vehicle body front wall arranged between a passenger compartment and an engine compartment, and a carrier element for such a sound-insulating element, by means of which the cost required to hold the carrier element in a molding tool on the tool side to mold a sound-absorbing material onto the carrier element can be reduced.

[0009] To solve this problem, the present invention proposes a sound-insulating element for a vehicle body front wall arranged between a passenger compartment and an engine compartment, wherein the sound-insulating element is provided with

[0010] - a composite part, including a plastic carrier layer and a sound-absorbing layer connected thereto,

[0011] - wherein the composite part has a front side facing the passenger compartment and formed by the outer surface of the plastic carrier layer when observed in its installed state, and a rear side adjacent to the front wall, which is formed by the outer side of the sound-absorbing layer facing away from the plastic carrier layer, and

[0012] - at least one first channel opening in the composite part,

[0013] - wherein the first channel opening includes a carrier layer hole having a hole edge formed in the plastic carrier layer and a sound-absorbing layer hole having a hole edge formed in the sound-absorbing layer, and

[0014] - wherein at least one pressing protrusion protrudes from the plastic carrier layer at the hole edge of the carrier layer hole and / or offset from the hole edge of the carrier layer hole on the outer side facing away from the plastic carrier layer and thus facing the sound-absorbing layer, and the pressing protrusion is embedded in the sound-absorbing material of the sound-absorbing layer, and the free end of the pressing protrusion facing away from the plastic carrier layer is substantially flush with the outer side of the sound-absorbing layer facing away from the plastic carrier layer.

[0015] Correspondingly, the present invention provides a pressing protrusion as part of the plastic carrier layer, that is, part of the carrier element of the sound-insulating element onto which the sound-absorbing material is molded, instead of a pressing protrusion provided on the molding tool. Such a pressing protrusion is located at the hole edge or offset outward from the hole edge of the channel opening, that is, the hole in the plastic carrier layer, and the pressing protrusion together with the hole aligned with it in the sound-absorbing layer forms a channel of the sound-insulating element.

[0016] In the sound-insulating element according to the invention, at least one pressing projection, which can be, for example, needle-shaped or dome-shaped, is embedded in the sound-absorbing material of the sound-absorbing layer. Advantageously, a plurality of such pressing projections are circumferentially present around the hole edge of the carrier layer hole. Different from the pressing projections (pressing pins) in the prior art, which are part of one of the forming tool components for molding the sound-absorbing material onto the plastic carrier layer, there are no cavities in the sound-absorbing layer after it is demolded from the forming tool; instead, the pressing projections of the plastic carrier layer extend into the sound-absorbing layer and may pass through it.

[0017] As described above, the sound-insulating element according to the invention is designed as a composite component and has a plastic carrier layer (so-called heavy layer) and a sound-absorbing layer made of a sound-absorbing material (such as PU foam). The composite component constructed in this way as a two-layer structure has two outer sides, one of which is formed by the plastic carrier layer and the other by the sound-absorbing layer. The inner sides of the two layers are in contact with each other; the two layers are connected to each other on the inner side. In the installed state, the outer side of the plastic carrier layer faces the passenger compartment; this side of the composite component forms the front side, while the rear side of the composite component is formed by the outer side of the sound-absorbing layer that abuts against the front wall.

[0018] At least one pressing projection now projects from the inner side of the plastic carrier layer in the hole region of the carrier layer, and the free end of this pressing projection facing away from the rear side of the plastic carrier layer is substantially flush with the outer side of the sound-absorbing layer. In, where the free end does not project beyond the outer side of the sound-absorbing layer, but is more preferably covered thinly by the sound-absorbing material (for example, at least 1 mm and at most 5 mm).

[0019] As already mentioned, it is useful to provide a plurality of pressing projections around the hole edge, and then these pressing projections advantageously take the form of pins or domes. The design of the pressing projection or at least one pressing projection should be selected such that when the sound-absorbing material is molded onto the plastic carrier layer in the forming tool, this sound-absorbing material can flow around and above at least one pressing projection. If, in a useful embodiment of the invention, a collar that at least partially surrounds the hole in the carrier layer is used as the pressing projection, the collar should have a groove in its circumferential wall or an edge groove opening towards the upper edge. With such a collar design, the sound-absorbing material introduced into the forming tool can flow through the collar.

[0020] The structure of the sound-insulating element according to the invention described above is particularly used to form a hole edge equipped with sound-absorbing material in a plastic carrier layer. The sound-absorbing material has a protruding area extending into the holes of the carrier layer, and this protruding area is flush with the outer side of the plastic carrier layer or protrudes forward so as to surround the edge of the hole on both sides. To prevent the undesired shearing of the sound-absorbing material in the hole edge area, a hook-shaped structure can be provided between the plastic carrier layer and the sound-absorbing layer through anchoring protrusions, through-holes, etc. formed by the sound-absorbing material. Examples of through-holes for filling sound-absorbing material in the plastic carrier layer in the penetration area of the sound-insulating element can be found in DE-A-41 32 571, EP-A-2 786 851, and JP H07-285 138A.

[0021] The individual embodiments of the invention are the subject matter of the dependent claims.

[0022] In an advantageous further refinement of the invention, the sound-absorbing material of the sound-absorbing layer protrudes inward beyond the hole edge of the carrier layer hole into a first hole and forms an annular protruding edge.

[0023] In this embodiment, it can also be advantageously provided that the protruding edge is aligned with the outer side of the plastic carrier layer or extends along at least a part of the hole edge of the carrier layer hole to the outer side of the plastic carrier layer. Advantageously, the sound-insulating element according to the invention can also be provided with at least one second channel opening in the composite component, and the second channel opening includes a carrier layer hole formed in the plastic carrier layer and a sound-absorbing layer hole formed in the sound-absorbing layer, and both holes have aligned hole edges.

[0024] In addition to the above-mentioned sound-insulating element according to the invention, according to the invention, the above object can also be solved by a load-bearing element for a sound-insulating composite component, which is arranged on the front wall of the vehicle body, and the front wall is arranged between the engine compartment and the passenger compartment, wherein the load-bearing element is provided with

[0025] - a plastic carrier layer having an outer side and an inner side, and in a molding tool having at least two molding tool parts, the sound-absorbing material of the sound-absorbing layer of the sound-insulating composite component can be applied or attached to the plastic carrier layer,

[0026] - at least one first carrier layer hole formed in the plastic carrier layer, and the first carrier layer hole has a hole edge, and

[0027] - at least one pressing protrusion arranged on and / or offset from the hole edge, and the pressing protrusion protrudes from the plastic carrier layer and protrudes from the inner side of the plastic carrier layer,

[0028] - wherein the plastic carrier layer can be introduced into the molding tool, with its outer side abutting against the first molding tool part, and the end of at least one pressing projection facing away from the inner side of the plastic carrier layer is arranged to contact the second molding tool part for holding the plastic carrier layer against the first molding tool part in the region of the hole edge of the first carrier layer hole.

[0029] In order to be able to realize the hole edge of the plastic carrier layer provided with sound insulation material in such a bearing element, for example, a first hole of the plastic carrier layer can be provided, which is arranged to penetrate radially with a clearance to the hole edge of the first carrier layer hole by means of a core, in particular by means of a core provided on the first or second molding tool part of the molding tool arranged on the rear side for molding the sound absorption material onto the plastic carrier layer.

[0030] The bearing element can advantageously be formed with a pressing projection structure as described previously in connection with the sound insulation element. In addition, the plastic carrier layer of the bearing element can be formed as described above in connection with the present invention. In particular, as provided above in the context of the present invention, the plastic carrier layer of the bearing element can be provided with sound insulation material and a sound absorption layer.

[0031] The present invention will be explained in more detail below by way of examples of embodiments and with reference to the accompanying drawings. Description of the Drawings

[0032] Figure 1 is an exploded perspective view of a vehicle body with a front wall sound insulation element,

[0033] Figure 2 is according to Figure 1 a perspective view of the multi-layer structure of the sound insulation element, i.e., the design of the plastic carrier layer,

[0034] Figure 3 is a cross-sectional view of a molding tool for molding sound insulation material onto the plastic carrier layer according to Figure 2 wherein the plastic carrier layer is inserted into the molding tool,

[0035] Figure 4 is Figure 3 a cross-sectional view of the molding tool shown after inserting the sound absorption material,

[0036] Figure 5 is a view of the rear side of the sound insulation element when the sound insulation element is mounted against the front wall of the vehicle body,

[0037] Figure 6 is a perspective view of the sound insulation element seen from the rear side,

[0038] Figure 7 is according to Figure 6 a cross-sectional view of the sound insulation element cut along line VII-VII, and

[0039] Figure 8 Is a perspective view of an alternative design of the pressing projection. Detailed implementation

[0040] Figure 1 Schematically shows a vehicle body 10 having a front wall 12, and a sound insulation element 14 designed as a composite part is arranged on the front wall 12. The sound insulation element 14 is fixed to the front wall 12 at least in part by fixing projections (not shown) integrally formed with the sound insulation element 14, and the fixing projections cooperate with corresponding receiving openings in the vehicle body 10 or the front wall 12 in the assembled state of the sound insulation element 14, and the fixing projections are placed in the receiving openings. In this regard, reference is made by way of example to WO-A-2018 / 192858, the content of which is hereby incorporated by reference as part of the subject matter of the present disclosure.

[0041] As is well known, the sound insulation element 14 has a so-called mass-spring system, which includes: a plastic carrier layer 16, as a heavy layer or mass layer made of, for example, EVA / PE, PE, PP, EPDM, TPE, TPO, and / or polyurethane foam, each of which has a high-density mineral filler with a high weight ratio of up to 70%, such as feldspar; and a sound-absorbing layer 18 made of a sound-absorbing material (such as polyurethane foam) (see, for example Figure 6 ).

[0042] In the installed state as Figure 1 shown, the sound insulation element 14 has a front side 20 facing the passenger compartment and a rear side 22 facing and adjacent to the front wall. The front side 20 is formed by the outer surface 24 of the plastic carrier layer 16, and the rear side 22 is formed by the outer surface 26 of the sound-absorbing layer 18. The plastic carrier layer 16 and the sound-absorbing layer 18 are connected to each other at their inner sides 28, 30 facing each other (see also Figure 7 ).

[0043] The sound insulation element 14 has a plurality of channel openings 32, 34, 36, 38, and in this embodiment, these channel openings have different shapes and are intended to show different types of channels of the sound insulation element. Except for the channel opening 34, the other channel openings 34 shown in the figure are provided with sound-absorbing material along the hole edges of the holes in the plastic carrier layer 16. Molding the sound-absorbing material along these hole edges requires a certain amount of positioning aids in the molding tool provided for the molding of the sound-absorbing material, as Figure 3 and 4 shown.

[0044] Figure 3Shows a cross-section through the two-piece forming tool 40 in this embodiment, which has a first forming tool part 42 and a second forming tool part 44. The prefabricated plastic carrier layer 16 is first placed in the cavity 46 of the forming tool 40, and the outer surface 24 of the plastic carrier layer rests on the inner surface of the first forming tool part 42. Then the forming tool 40 is moved together. In this exemplary embodiment, four holes 48, 50, 52, 54 with hole edges 49, 51, 53, 55 are formed in the plastic carrier layer 16. The core 56 extends into the hole 54 and completely fills the hole 54. The cores 58, 60, 62 each extend into the holes 48, 50, 52, and the cross-sections of these cores are smaller than the holes, so that free spaces 64, 66, 68 are left between the cores and the hole edges 49, 51, 53 in the cavity 46.

[0045] Therefore, the free spaces are filled with a sound-absorbing material, as shown with reference to Figure 3 and 4 When such a material is introduced into the forming tool 40 through, for example, one (in particular several) inlets 70. The cores 56, 58, 60, 62 provide holes 57, 59, 61, 63 in the sound-absorbing layer 18 of the sound-insulating element 14, and the holes 57, 59, 61, 63 are respectively aligned with the carrier layer holes 48, 50, 52, 54.

[0046] The penetration of the sound-absorbing material into the holes 48, 50, 52 (no material penetrates into this hole because the core 56 completely fills the hole 54) poses a risk that the plastic carrier layer 16 is "washed away" and then "floats" in the cavity 46. To prevent this, in the region of each hole 48, 50, 52, pressing protrusions 72 (all in the form of pins or domes in this embodiment) protruding from the inner side 28 of the plastic carrier layer 16 are arranged, and the pressing protrusions 72 abut against the inner side 74 of the second forming tool part 44 that defines the cavity 46, or their free ends 76 are arranged at a very short distance from the forming tool part 44. The pressing protrusions 72 hold the plastic carrier layer 16 in position against the inner side 78 of the first forming tool part 42. This prevents the plastic carrier layer 16 from "floating" when the sound-absorbing material penetrates and flows around the edges of the holes 48, 50, 52.

[0047] Depending on the desired design of enclosing or surrounding or partially surrounding the edges of the holes 48, 50, 52 with the sound-absorbing material, the plastic carrier layer 16 has different structures in the region of the said holes, as shown in Figure 3 and 4 or Figure 6 and 7As shown. For example, the protruding edge 80 in the hole 48 is aligned with the outer surface 24 of the plastic carrier layer 16, while the corresponding protruding edges 82, 84 of the holes 50, 52 surround the hole edges 51, 53 from both sides. Regarding the design of the hole 52, additionally provided is an additional hook structure or similar protrusion 86 protruding from the front side 20 of the plastic carrier layer 16, which is embedded in the sound-absorbing material and thus ensures an additional hold of the sound-absorbing layer 18 on the front side 20 of the plastic carrier layer 16.

[0048] Figure 8 An alternative embodiment of the pressing protrusion 88 is shown. In this embodiment, the pressing protrusion 88 is formed as a circumferential collar 90 extending around an opening in the plastic carrier layer denoted by 92. The collar 90 has a hole 94 through which the sound-insulating material can reach near or around the edge of the hole in the plastic carrier layer 92, as Figure 3 shown in the hole design. In the state where the sound-insulating material is provided, the pressing protrusion 88 is embedded in the material.

[0049] List of Reference Numerals

[0050] 10 Body

[0051] 12 Front wall

[0052] 14 Sound-insulating element

[0053] 16 Plastic carrier layer

[0054] 18 Sound-absorbing layer

[0055] 20 Front side

[0056] 22 Rear side

[0057] 24 Outer surface of the front side

[0058] 26 Outer side

[0059] 28 Inner side

[0060] 30 Inner side

[0061] 32 Channel opening

[0062] 34 Channel opening

[0063] 36 Channel opening

[0064] 38 Channel opening

[0065] 40 Two-piece molding tool

[0066] 42 First molding tool part

[0067] 44 Second molding tool part

[0068] 46 mold cavities

[0069] 48 carrier layer holes

[0070] 49 hole edges

[0071] 50 carrier layer holes

[0072] 51 hole edges

[0073] 52 carrier layer holes

[0074] 53 hole edges

[0075] 54 carrier layer holes

[0076] 55 hole edges

[0077] 56 mold cores

[0078] 57 sound-absorbing layer holes

[0079] 58 mold cores

[0080] 59 sound-absorbing layer holes

[0081] 60 mold cores

[0082] 61 sound-absorbing layer holes

[0083] 62 mold cores

[0084] 63 sound-absorbing layer holes

[0085] 64 free space

[0086] 66 free space

[0087] 68 free space

[0088] 70 inlet

[0089] 72 pressing protrusions

[0090] 74 inner side of the mold cavity

[0091] 76 free end of the pressing protrusion

[0092] 78 inner side of the mold cavity

[0093] 80 protruding edge

[0094] 82 protruding edge

[0095] 84 protruding edge

[0096] 86 protrusion

[0097] 88 pressing protrusions

[0098] 90 collar

[0099] 92 Plastic carrier layer

[0100] 94 Hole of the collar

[0101] References

[0102] WO-A-2018 / 192858

[0103] US-A-2006 / 0091699

[0104] DE-A-37 33 284

[0105] EN-A-10 2013 006 300

[0106] EN-C-198 33 098

[0107] DE-A-41 32 571

[0108] EP-A-2 786 851

[0109] JP H07-285 138 A

Claims

1. A sound insulation element for a vehicle body front wall, disposed between a passenger compartment and an engine compartment, having - a composite part including a plastic carrier layer (16) and a sound-absorbing layer (18) connected thereto, - wherein, when observed in the installed state of the composite part, the composite part has a front side (20) facing the passenger compartment and formed by an outer surface (24) of the plastic carrier layer (16), and a rear side (22) which abuts against the front wall and is formed by an outer side (26) of the sound-absorbing layer (18) facing away from the plastic carrier layer (16), and - at least one first channel opening in the composite part, - wherein the first channel opening includes: carrier layer holes (48, 50, 52, 54) formed in the plastic carrier layer (16) and having hole edges (49, 51, 53, 55); and sound-absorbing layer holes (57, 59, 61, 63) formed in the sound-absorbing layer (18) and having hole edges, - wherein at least one pressing projection (72) projects at the hole edges (49, 51, 53, 55) of the carrier layer holes (48, 50, 52, 54) and / or deviates from the hole edges (49, 51, 53, 55) of the plastic carrier layer (16) on an inner side (28) of the outer surface (24) facing away from the plastic carrier layer (16) and thus facing the sound-absorbing layer (18), wherein the sound-absorbing material of the sound-absorbing layer (18) projects inwards beyond the hole edges (49, 51, 53, 55) of the carrier layer holes (48, 50, 52, 54) and forms an annular protruding edge (80, 82, 84); the pressing projection (72) is embedded in the sound-absorbing material of the sound-absorbing layer (18) and its free end facing away from the plastic carrier layer (16) is substantially aligned with the outer side of the sound-absorbing layer (18) facing away from the plastic carrier layer (16); wherein a plurality of pressing projections (72) are circumferentially arranged around the carrier layer holes (48, 50, 52, 54).

2. The sound insulation element according to claim 1, characterized in that, The free end (76) of the at least one pressing projection (72) facing away from the inner side (28) of the plastic carrier layer (16) is covered with sound-absorbing material.

3. The sound insulation element according to claim 1 or 2, characterized in that The at least one pressing projection (72) is formed as a pin-shaped projection or a pressing dome.

4. The sound insulation element according to claim 1 or 2, characterized in that The at least one pressing projection (72) is formed as a collar surrounding the carrier layer holes (48, 50, 52, 54) and having a circumferential opening.

5. The sound insulation element according to claim 1, characterized in that, The protruding edges (80, 82, 84) are aligned with the outer surface (24) of the plastic carrier layer (16) or extend onto the outer surface (24) of the plastic carrier layer (16) along at least a part of the hole edges (49, 51, 53, 55) of the carrier layer holes (48, 50, 52, 54).

6. The sound insulation element according to any one of claims 1 to 5, characterized in that, The at least one second channel opening in the composite part includes: carrier layer holes (48, 50, 52, 54) formed in the plastic carrier layer (16); and sound-absorbing layer holes (57, 59, 61, 63) formed in the sound-absorbing layer (18), wherein the two holes have aligned hole edges.

7. A bearing element for a sound insulation element for a vehicle body front wall disposed between an engine compartment and a passenger compartment, having - A plastic carrier layer (16) having an outer side and an inner side, to which the sound-absorbing material of the sound-absorbing layer (18) of the sound-insulating element can be applied or which can be applied to a forming tool having at least two forming tool parts, - At least one carrier layer hole, the hole edge of which is formed in the plastic carrier layer (16), and - At least one pressing projection (72) provided on and / or offset from the hole edge, protruding from the plastic carrier layer (16) and protruding from the inside of the plastic carrier layer (16), - Wherein the plastic carrier layer (16) can be introduced into a forming tool, the outer side thereof abuts against the first forming tool part, and the end of at least one pressing projection (72) remote from the inner side of the plastic carrier layer (16) is arranged to contact the second forming tool part for holding the plastic carrier layer (16) against the first forming tool part in the region of the hole edge of the carrier layer hole, Wherein the sound-absorbing material of the sound-absorbing layer (18) protrudes inwards beyond the hole edges (49, 51, 53, 55) of the carrier layer holes (48, 50, 52, 54) and forms an annular protruding edge (80, 82, 84); Among them, A plurality of pressing projections (72) are circumferentially arranged around the carrier layer holes (48, 50, 52, 54).

8. The bearing element according to claim 7, characterized in that, The first hole of the plastic carrier layer (16) is arranged to be penetrated by a core, and the core has a radial clearance from the hole edge of the carrier layer hole.

9. The load-bearing element according to claim 8, characterized in that, The core is arranged on the first or second forming tool part of a forming tool provided for molding the sound-absorbing material onto the rear side of the plastic carrier layer (16).

10. The load-bearing element according to any one of claims 7 to 9, characterized in that, The at least one pressing projection (72) is formed in the sound-insulating element as described in any one of claims 1 to 6, and / or, the plastic carrier layer (16) is formed in the sound-insulating element as described in any one of claims 1 to 6, and / or, the plastic carrier layer (16) is provided with a sound-absorbing layer (18) or sound-absorbing material as described in any one of claims 1 to 6 of the sound-insulating element.

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