DUST SHEET FOR REDUCING BRAKE NOISE AND BRAKE SYSTEM COMPRISING A DUST SHEET

Abstract

The invention relates to a dust sheet for a vehicle brake, configured for reducing brake noise, wherein the dust sheet comprises sub-centimetre damping structures for attenuating airborne sound, the damping structures being formed by a plurality of holes and/or a plurality of embossings. The invention also relates to a brake system for a vehicle, in particular a disk brake system, comprising such a dust sheet.

Claims

1. A dust sheet for a vehicle brake, configured for reducing brake noise, wherein the dust sheet comprises sub-centimetre damping structures for attenuating airborne sound, the damping structures being formed by a plurality of holes and/or a plurality of embossings.

2. The dust sheet according to claim 1, wherein, in at least one spatial direction on a surface of the dust sheet, an areal extension of the holes and/or an areal extension of the embossings is at most 3 mm, or at most 2 mm, or at most 1 mm.

3. The dust sheet according to claim 1, wherein a distance between nearest-neighbouring holes and/or a distance between nearest neighbouring embossings is at least 5 mm or at least 8 mm and/or at most 20 mm or at most 15 mm, in particular the distance between nearest-neighbouring holes and/or nearest-neighbouring embossings being 10 mm.

4. The dust sheet according to claim 1, wherein a diameter or a cross section of the holes or embossings is at least 0.3 mm or at least 0.4 mm or at least 0.5 mm and/or at most 1.5 mm or at most 1.25 mm or at most 1 mm.

5. The dust sheet according to claim 1, comprising a total of at least 50 holes or embossings or at least 100 holes or embossings or at least 150 holes or embossings or at least 180 holes or embossings and/or at most 400 holes or embossings or at most 300 holes or embossings or at most 250 holes or embossings or at most 220 holes or embossings.

6. The dust sheet according to claim 1, wherein the embossings comprise at least one raised embossing and/or at least one depressed embossing.

7. The dust sheet according to claim 1, wherein the plurality of holes or embossings have an elongated shape, in particular with a straight course and/or a curved course and/or a zigzag course.

8. The dust sheet according to claim 7, wherein the embossings or holes have a width of at most 2 mm or at most 1.5 mm or at most 1 mm and/or a length of at least 0.5 cm or at least 1 cm or at least 2 cm and/or at most 10 cm or 8 cm or 5 cm.

9. The dust sheet according to claim 7, wherein the dust sheet includes at least 5 holes or embossings or at least 10 holes or embossings or at least 15 holes or embossings and/or at most 50 holes or embossings or at most 40 holes or embossings.

10. The dust sheet according to claim 1, wherein the embossings have a depth or a height of at least 0.1 mm or at least 0.2 mm or at least 0.5 mm and/or at most 2 mm or at most 1 mm.

11. The dust sheet according to claim 1, wherein the dust sheet is made of a temperature resistant plastic or of a temperature resistant matrix material, in particular a textile-like matrix material.

12. The dust sheet according to claim 1, wherein the dust sheet is devoid of metal.

13. The dust sheet according to claim 1, wherein a thickness of the dust sheet is at least 1 mm and/or at most 4 mm or at most 3 mm or at most 2 mm.

14. The dust sheet according to claim 1, wherein the dust sheet comprises a first layer, comprising the plurality of holes and/or the plurality of embossings, and at least one additional layer which is arranged plane-parallel to the first layer.

15. The dust sheet according to claim 14, wherein at least one additional layer comprises at least one cover layer, preferably a temperature-resistant cover layer, in particular made from a material that is flexible and/or soft and/or designed as a textile-like fabric or web.

16. The dust sheet according to claim 14, wherein the at least one cover layer is arranged on a side that is configured to face a brake disk and/or on a side that is configured to face away from the brake disk.

17. The dust sheet according to claim 14, wherein the at least one additional layer comprises an equivalent layer to the first layer, the equivalent layer being made of the same material as the first layer and/or having the same thickness as the first layer.

18. The dust sheet according to claim 17, wherein the equivalent layer is arranged at a distance of at least 0.2 mm and/or at most 0.5 mm from the first layer.

19. The dust sheet according to claim 17, wherein the equivalent layer comprises sub-centimetre damping structures for attenuating airborne sound, the damping structures of the equivalent layer being formed by a further plurality of holes and/or a further plurality of embossings.

20. The dust sheet according to claim 1, wherein the damping structures are arranged at least in a section of the dust sheet that is configured to face a portion of the brake disk that is opposite to a point of engagement of the brake disk with a brake pad of the brake system.

21. The dust sheet according to claim 1, wherein the damping structures are provided in a section of the dust sheet that is configured to extend over at least 10% of an area of the brake disk or at least 20% or at least 30%.

22. A brake system for a vehicle, in particular a disk brake system, comprising a dust sheet according to claim 1.

23. A brake system according to claim 22, wherein a distance between the dust sheet and a brake disk is at least 0.5 mm or at least 0.6 mm and/or at most 2 mm or at most 1.5 mm or at most 1 mm.

Description

[0037] The invention shall now be explained in an exemplary manner, with reference to the appended figures.

[0038] Therein:

[0039] FIGS. 1a-c schematically show different views of a vehicle brake comprising a dust sheet,

[0040] FIGS. 2a-n illustrate embodiments of the dust sheet with embossings,

[0041] FIGS. 3a-e illustrate further embodiments of the dust sheet with embossings,

[0042] FIGS. 4a-d illustrate further embodiments of the dust sheet with embossings, the embossings arranged in a grid-like pattern,

[0043] FIGS. 5a-g illustrate further embodiments of the dust sheet with embossings, carried out as elongated embossings,

[0044] FIGS. 6a-e illustrate embodiments of the dust sheet with holes,

[0045] FIGS. 7a-b show embodiments having holes and embossings,

[0046] FIGS. 8a-b illustrate a dust sheet with a cover layer, and

[0047] FIGS. 9a-b illustrate a dust sheet with a first layer and an equivalent second layer.

[0048] FIG. 1a shows a side view onto an inner side of a disk brake system. All figures are for illustrative purposes and are not to scale. The brake system comprises a brake disk 10, a caliper 20, and a dust sheet 1. The dust sheet 1 is configured for reducing brake noise, wherein the dust sheet 1 comprises sub-centimetre damping structures for attenuating airborne sound. The damping structures are formed by a plurality of holes 3 and/or a plurality of embossings 2, as will be explained further in the context of FIGS. 2-6.

[0049] The dust sheet 1 is arranged to cover a portion of the brake disk 10, extending over more than half of an area of the brake disk 10.

[0050] The damping structures are arranged at least in a section B of the dust sheet, which faces a portion of the brake disk 10 that is opposite to a point of engagement of the brake disk 10 with a brake pad of the brake system, which brake pad is held by the caliper 20. The section B, which has the damping structures, extends over at least 30% of an area of the brake disk.

[0051] FIGS. 1b and 1c show cuts through the brake system, along the line B-B from FIG. 1a. In the case of FIG. 1b a single dust sheet 1 according to this invention is arranged on an inner side of the brake disk 10. In the case of FIG. 1c, two dust sheets 1, 1′ according to the invention are provided, one on each side of the brake disk 10. The section B, which has the holes 3 or embossings 2 is indicated for each of the dust sheets 1, 1′ in FIGS. 1b and 1c. It is also possible, to provide a dust sheet 1 according to the invention only on an outer side of the brake disk 10.

[0052] Relating to FIGS. 1a-c, in each case, a distance between the dust sheet 1 and the brake disk 10 is between 0.6 mm and 1 mm. A thickness of the dust sheet 1 is between 1 mm and 4 mm.

[0053] The dust sheet 1 is made of a temperature resistant plastic or of a temperature resistant matrix material, such as a textile-like matrix material. The dust sheet is preferably devoid of metal.

[0054] FIG. 2a shows once again the cut A-A. A circle marks a portion of the dust sheet, which lies within the section B, having the damping structures. FIGS. 2b-2o show the circled portion in an enlarged manner, so that the damping structures can be seen. FIGS. 2b-2o relate to embodiments having embossings 2. The embossings 2 may be carried out as raised embossings 2′ and/or as depressed embossings 2″, as explained further below. FIGS. 2b-2o illustrate the height and shape of the embossings, and their width as it can be seen in a view corresponding to the cut A-A. No further assumptions are made with regard to their areal extension into the plane of the paper, which is not visible in the cut view. Areal extension along the two dimensions defined by the plane of the dust sheet 1 will be discussed in the context of FIGS. 4 and 5.

[0055] FIGS. 2b-2k focus on embodiments where the embossings 2 are provided only on a side of the dust sheet 1 which faces the brake disk 10. Additionally, embossings 2 are provided on the side facing away from the brake disk 10, in the case of FIGS. 2l-2n.

[0056] FIG. 2b shows an embodiment having a multitude of raised embossings 2′ with identical height, width and shape. They are in each case between 0.5 and 1 mm high, as indicated in the figure.

[0057] FIG. 2c shows raised embossings of different, alternating height, with a maximum height of between 1 mm and 2 mm.

[0058] FIG. 2d shows a multitude of identical depressed embossings 2″, each with a depth of between 1 mm and 2 mm.

[0059] The dimensions (heights/depths) of FIGS. 2b-2d may advantageously be applied to the embossings shown in the following figures.

[0060] FIG. 2e shows several depressed embossings 2″, which differ from each other in depth, and in width.

[0061] FIG. 2f shows a plurality of raised embossings 2′ with sloped side-walls.

[0062] FIG. 2g shows a plurality of raised embossings 2′ with sloped side-walls, with alternating height.

[0063] FIG. 2h shows a plurality of raised embossings 2′ with rounded edges.

[0064] FIG. 2i shows a plurality of raised embossings 2′ with rounded edges, with alternating height.

[0065] FIG. 2j, shows a plurality of depressed embossings 2″, whose widths differ from one another.

[0066] FIG. 2j, shows a plurality of raised embossings 2′, whose widths differ from one another.

[0067] FIG. 2l shows an embodiment having raised embossings 2′ on both sides. The embossings 2′ on either side may be carried out as shown in either of FIGS. 2b-2k.

[0068] FIG. 2m shows an embodiment having raised embossings 2′ facing the brake disk 10, and depressed embossings 2′ facing away from the brake disk 10. The embossings 2′, 2″ on either side may be carried out as shown in either of FIGS. 2b-2k.

[0069] FIG. 2n shows an embodiment having raised embossings 2′ facing away from the brake disk 10, and depressed embossings 2″ facing the brake disk 10. The embossings 2′, 2″ on either side may be carried out as shown in either of FIGS. 2b-2k.

[0070] FIGS. 3a-3e show embossings 2 that are carried out in such a manner that material is displaced to affect both sides of the dust sheet 1, i.e. a depression on one side goes along with a protrusion on the opposing side. The embossings of this type may be punched or drawn. FIG. 3b-3d show embodiments having step-like depressed and raised embossings 2′, 2″ in alternating fashion, on both sides of the disk. FIG. 3d has a double-step pattern. FIG. 3e shows an embodiment wherein rounded depressions 2″ are formed on the side of the brake disk 10, displacing material away from the brake disk 10 and resulting in rounded protrusions 2′ on the side that faces away from the brake disk.

[0071] FIGS. 4a-4d show views onto an inner surface of the dust sheet 1, which inner surface faces the brake disk 10. The figures illustrate areal extensions of the embossings 2, i.e. extension of the embossings over the inner surface of the dust sheet 1. Therein, FIGS. 4a-4b relate to shapes that are restricted in both areal dimensions. These embodiments comprise between 180 and 220 embossings 2, which are arranged in a grid-like pattern. For illustrative purposes, only a much smaller number of embossings is shown in the Figures. The grid-like patterns are shown as rectangular grids. Other grid-types and even randomly distributed arrangements are also possible.

[0072] No assumptions are made with regard to the remaining properties of the embossings 2 which are not visible in FIGS. 4a-4d. The embossings 2 may be carried out as raised embossings 2′, depressed embossings 2″, or as a combination thereof. They may have the properties shown in either of FIGS. 2-3 and all of their subfigures. They may also be combined with holes 3, in particular they may form a common pattern with holes 3, which holes 3 will be explained in the context of FIG. 6.

[0073] In the cases of FIGS. 4a-4d, areal extension of the embossings (2) is restricted in both areal dimensions to at most 1 mm. I.e., a diameter or a cross section of the embossings 2 is at most 1 mm. The diameter or the cross section may be as small as for instance 0.5 mm or 0.3 mm.

[0074] Referring once again to each of FIGS. 4a-4d, a distance between nearest-neighbouring embossings 2 is less than 15 mm and may be as small as for instance 5 mm.

[0075] FIG. 4a shows elliptic embossings 2, namely circular embossings 2.

[0076] FIG. 4b shows polygonal embossings 2, namely rectangular embossings 2.

[0077] FIG. 4c shows circular embossings 2 which are carried out as rings, as can be seen in the cut C-C pertaining to FIG. 4c.

[0078] FIG. 4d shows an embodiment having polygonal embossings 2 with a cross-like shape.

[0079] FIGS. 5a-5g relate to embodiments with embossings 2 that are carried out as elongated embossings. They may be designed as depressed 2″ and/or raised embossings 2′ (as schematically shown in FIGS. 5b and 5c). They may have any of the shapes indicated for instance in FIGS. 2 and 3.

[0080] The elongated embossings of FIGS. 5a-5g are area-wise restricted in one dimension only. They can have a width of at most 3 mm, or at most 2 mm, or at most 1 mm. They may have a distance of 10 mm or less from one another.

[0081] Their length may be at least 2 cm and for instance up to 10 cm.

[0082] The embossings 2 with an elongated shape can have a straight course and/or a curved course and/or a zig-zag course. FIG. 5d shows a straight course, which runs horizontally across the dust sheet 1.

[0083] The dust sheet with elongated embossings 2 may include at least 10 embossing 2 or at least 15 embossings 2, and for instance up to 50 of these embossings 2

[0084] FIG. 5e illustrates elongated embossings 2 extending horizontally across the dust sheet 1.

[0085] FIG. 5f illustrates elongated embossings 2 extending vertically across the dust sheet 1.

[0086] FIG. 5g illustrates elongated embossings 2 extending diagonally across the dust sheet 1.

[0087] FIGS. 6a and 6b illustrate a dust sheet 1 with holes 3, i.e. through-holes. The holes are distributed in the dust sheet 1 and they may be arranged in the same patterns that were shown for the embossings 2 above. A diameter or cross-section of the holes is less than 1 mm and for instance down to 0.3 mm, as shown in the Figure.

[0088] FIGS. 6c-6e illustrate different shapes for the holes 3. The holes 3 of FIG. 6c are circular, the holes 3 of FIG. 6d are rectangular, and the holes of FIG. 6e are cross-shaped. Like before, in the case of the embossings 2, the holes are arranged in grid-patterns. A distance between nearest-neighbouring holes 3 is less than 15 mm and may be as small as for instance 5 mm.

[0089] The dust sheet 1 has at least 180 holes 3 and may has between 180 and 220 holes 3.

[0090] FIGS. 7a-b show embodiments wherein the dust sheet 1 has both holes 3 and embossings 2. In these examples, the embossings 3 and holes 2 are arranged in a grid-like pattern, in alternating fashion.

[0091] FIGS. 8 and 9 relate to embodiments, wherein the dust sheet 1 has an additional layer 5.

[0092] FIGS. 8a-b show a dust sheet having a first layer 4, which first layer 4 may have the holes 3 and/or embossings 2 as explained herein.

[0093] The dust sheet furthermore comprises the additional layer 5, which is arranged plane-parallel to the first layer 4 and carried out as a temperature resistant cover-layer 5′, having a thickness of between 0.2 and 0.5 mm. It is made from a flexible, soft material, in particular a textile-like fabric or web.

[0094] The cover layer 5′ is arranged on a side that is configured to face the brake disk 10. Additionally or alternatively, a cover layer 5′ of this type may be arranged on the opposite side of the dust sheet 1.

[0095] FIGS. 9a-b show a further embodiment which includes a first layer 4, which may have the holes 3 and/or embossings 2 as explained herein, and an additional layer 5. The additional layer 5 is arranged plane-parallel to the first layer 4 and it is carried out as an equivalent layer 5″ to the first layer 4. The equivalent layer 5″ is made of the same material as the first layer 4 and it has the same thickness as the first layer 4.

[0096] The equivalent layer 5″ is arranged at a distance of between 0.2 mm and 0.5 mm from the first layer 4. The first layer 4 and the equivalent layer 5″ are connected by a web 6. The equivalent layer 5″ also comprises sub-centimetre damping structures for attenuating airborne sound, the damping structures of the equivalent layer 5″ being formed by a further plurality of holes and/or a further plurality of embossings. The further holes and/or embossings may be carried out like the holes 3 and embossings 2 of the first layer 4, which are explained herein.

LIST OF REFERENCE NUMERALS

[0097] 1, 1′ Dust Sheet [0098] 2 Embossing [0099] 2′ Embossing (raised) [0100] 2″ Embossing (depressed) [0101] 3 Hole [0102] 4 First Layer [0103] Additional Layer [0104] 5′ Cover Layer [0105] 5″ Equivalent Layer [0106] 6 Web [0107] Brake Disk [0108] 20 Caliper