US-12617239-B2 - Pneumatic tire for a vehicle

US12617239B2US 12617239 B2US12617239 B2US 12617239B2US-12617239-B2

Abstract

A pneumatic tire for a vehicle, having at least one surface element that is formed on the outer surface of the tire and has a structure which contrasts with a base level and gives the surface element a roughness. The contrast structure is formed by a multiplicity of contrast structure cells, which coincide in shape in plan view and are joined together in the form of a grid. The contrast structure cells have irregular peak and trough structures of a surface-covering configuration. The arrangement of the contrast structure cells and the configuration of the irregular peak and trough structures are such that, when considered in plan view, the irregular peak and trough structures can be transferred one into the other by congruence mapping.

Inventors

Stefan Rittweger
Juraj Jurco

Assignees

CONTINENTAL REIFEN DEUTSCHLAND GMBH

Dates

Publication Date: 20260505
Application Date: 20211125
Priority Date: 20201202

Claims (8)

1 . A pneumatic tire for a vehicle, the tire comprising: at least one surface element formed on an outer face of the tire and has a contrast structure that contrasts with a base level and gives the surface element a roughness, wherein the contrast structure is formed by a plurality of contrast structure cells that coincide in shape in plan view and are joined together in the form of a grid, with each contrast structure cell constituting a unit cell of the grid, wherein the contrast structure cells have peak structures and trough structures, each of the peak and trough structures running over the contrast structure cell asymmetrically and non-uniformly when viewed in plan view, such that the peak and trough structures together form an irregular surface-covering configuration within each contrast structure cell when viewed in plan view, wherein the peak structures further provide irregularity by changing elevations relative to the base level as the peak structures run over the contrast structure cell; wherein, in cross-section perpendicular to the base level (NB), each contrast structure cell has a height profile with multiple local maxima (P max) at the peak structures and multiple local minima (P min) at the trough structures, wherein the height profile has at least one height difference (Δh) in a range from 80 μm to 300 μm, as measured perpendicular to the base level (NB) from a height of at least one of the local minima (P min) at a respective trough structure to a height of at least one of the local maxima (P max) at a peak structure adjacent to that respective trough structure; wherein, when viewed in plan view, the irregular surface-covering configuration formed by the peak and trough structures in each contrast structure cell is repeated by translation congruence mapping across the grid of the contrast structure, so that the irregular surface-covering configuration within each contrast structure cell in the grid has the same orientation as each other; wherein the contrast structure, has valleys which extend along mutual connection points of the contrast structure cells to delineate the contrast structure cells; and wherein the contrast structure cells have an edge length measured between the valleys of 0.8 mm to 1.5 mm.
2 . The tire of claim 1 , wherein the contrast structure cells ( 6 a ), as delineated by the valleys, have the shape of rectangles or hexagons in plan view, and the valleys have a width of at least 0.1 mm.
3 . The tire of claim 1 , wherein the irregular peak and trough structures ( 6 b ) of each contrast structure cell ( 6 a ) with a height surface region (f 1 ), extending over the region of the contrast structure cell ( 6 a ), of a first height surface (F 1 ), which extends parallel to the base level (N B ) of the contrast structure ( 6 ) and, with respect thereto, lies at a height (h 1 ) of 80 μm, has a multi-part sectional surface (s 1 ), which occupies 80% to 90% of the height surface region (f 1 ).
4 . The tire of claim 3 , wherein the irregular peak and trough structures ( 6 b ) of each contrast structure cell ( 6 a ) with a height surface region (f 2 ), extending over the region of the contrast structure cell ( 6 a ), of a second height surface (F 2 ), which extends parallel to the base level (N B ) of the contrast structure ( 6 ) and, with respect thereto, lies at a height (h 2 ) of 150 μm, has a multi-part sectional surface (s 2 ), which occupies 40% to 60% of the height surface region (f 2 ).
5 . The tire of claim 4 , wherein the irregular peak and trough structures ( 6 b ) of each contrast structure cell ( 6 a ) with a height surface region (f 3 ), extending over the region of the contrast structure cell ( 6 a ), of a third height surface (F 3 ), which extends parallel to the base level (N B ) of the contrast structure ( 6 ) and, with respect thereto, lies at a height (h 3 ) of 200 μm, has a multi-part sectional surface (s 3 ), which occupies 20% to 40% of the height surface region (f 3 ).
6 . The tire of claim 5 , wherein the irregular peak and trough structures ( 6 b ) of each contrast structure cell ( 6 a ) with a height surface region (f 4 ), extending over the region of the contrast structure cell ( 6 a ), of a fourth height surface (F 4 ), which extends parallel to the base level (N B ) of the contrast structure ( 6 ) and, with respect thereto, lies at a height (h 4 ) of 280 μm, has a single-or multi-part sectional surface (s 4 ), which occupies 10% to 20% of the height surface region (f 4 ).
7 . The tire of claim 6 , wherein the height surface regions (f 4 ) of the fourth height surface (F 4 ) separate peak regions ( 6 c ) from the rest of the contrast structure ( 6 ), wherein up to five, peak regions ( 6 c ) sit on each height surface region (f 4 ) and have, at their highest points, a height (h max ), determined with respect to and perpendicular to the base level (NB), of 300 μm to 350 μm.
8 . The tire of claim 1 , wherein the irregular peak and trough structures ( 6 b ) of each contrast structure cell ( 6 a ) with height surface regions (f 1 , f 2 , f 3 , f 4 ) which extend over the region of the contrast structure cell ( 6 a ) and which belong to height surfaces (F 1 , F 2 , F 3 , F 4 ) extending parallel to the base level (N B ) of the contrast structure ( 6 ) has, in each case, a multi-part sectional surface (s 1 , s 2 , s 3 , s 4 ), wherein a first height surface (F 1 ) with respect to the base level (N B ) lies at a height (h 1 ) of 80 μm, a second height surface (F 2 ) with respect to the base level (N B ) lies at a height (h 2 ) of 150 μm, a third height surface (F 3 ) with respect to the base level (N B ) lies at a height (h 3 ) of 200 μm, and a fourth height surface (F 4 ) with respect to the base level (N B ) lies at a height (h 4 ) of 280 μm, wherein the following relationships apply: a) size of the sectional surface (s 4 ) with the height surface region (f 4 ) of the fourth height surface (F 4 )≤0.7×the size of the sectional surface (s 3 ) with the height surface region (f 3 ) of the third height surface (F 3 ), b) size of the sectional surface (s 3 ) with the height surface region (f 3 ) of the third height surface (F 3 )≤0.7×the size of the sectional surface (s 2 ) with the height surface region (f 2 ) of the second height surface (F 2 ), and c) size of the sectional surface (s 2 ) with the height surface region (f 2 ) of the second height surface (F 2 )≤0.7×the size of the sectional surface (s 1 ) with the height surface region (f 1 ) of the first height surface (F 1 ).

Description

The invention relates to a pneumatic tire for a vehicle having formed on its outer surface at least one surface element with a structure that contrasts with a base level which imparts a roughness to the surface element. A tire of the type stated at the outset is known from FR 3 075 099 A1, for example. The tire has a tread and sidewalls, wherein at least one surface element with a contrast structure is formed on the tread and/or on at least one sidewall. The contrast structure has a plurality of peaks formed in an irregular manner at a density of at least one peak per square millimeter. More preferably, the peaks are formed in a density of at most 100 peaks per square millimeter. The peaks have a height of 50 μm to 600 μm, preferably of 100 μm to 400 μm, particularly preferably of 200 μm to 350 μm. This contrast structure is intended to provide a good contrast effect regardless of the viewing angle. A rubber article, for example a tire, is known from DE 20 2014 010 855 U1, on the outer surface of which there is formed a surface element with a contrast structure. The contrast structure has at least one first surface part and at least one second surface part, wherein the reflectance of the first surface part is greater than that of the second surface part. The surface parts are parts of a digital code pattern. DE 10 2013 223 567 A1 discloses a pneumatic tire for a vehicle, one sidewall of which has an optoelectronically readable code. The code is formed by cells of two different cell types. The cells have a surface profile, wherein the surface profiles are such that the reflection properties of one cell type differ from those of the other cell type. It is therefore known that surface elements having a contrast structure can be formed on the outer surface of pneumatic tires for vehicles, in particular on sidewalls, said surface elements primarily having the task of creating a contrast with other surface regions, in particular unstructured surface regions, in order in this way, for example, to make it easier to distinguish symbols on the sidewalls, e.g. design elements or logos. Surface elements having contrast structures make this possible since—in comparison with smooth surfaces—they reflect less light, that is to say “capture” incident light and therefore appear darker to the observer than smooth surface regions. In particular, uniform contrast structures consisting of a large number of ribs running parallel to one another are known. Furthermore, irregular contrast structures consisting of “finer” structures—compared to the ribs—i.e. significantly smaller, point-like elevations and/or hole-shaped depressions are known, which are produced in particular by laser engraving of the molded parts. When designing ribs forming uniform contrast structures, the orientation of the ribs must be adapted to the shape of the particular surface element in order to achieve a sufficiently good contrast effect. Due to the parallel arrangement of the ribs, the ribs reflect more light at certain viewing angles, while they in turn reflect little to hardly any light at certain other viewing angles, so that the contrast effect is not optimal in this respect. Irregular contrast structures can be used much more flexibly than ribs and show a more uniform, largely direction-independent light reflection. However, the creation of completely irregular contrast structures on large surface areas, as is desirable or necessary on the sidewalls of tires, for example, is only possible with very complex laser engraving. The object of the invention is therefore to provide, in a tire of the type mentioned at the outset, a contrast structure of which the size is easily scalable and of which the contrast effect is at least largely independent of direction. The stated object is achieved according to the invention in that the contrast structure is formed by a multiplicity of contrast structure cells, which coincide in shape in plan view and are joined together in the form of a grid, wherein the contrast structure cells have irregular peak and trough structures of a surface-covering configuration, wherein the arrangement of the contrast structure cells and the configuration of the irregular peak and trough structures are such that the irregular peak and trough structures, when considered in plan view, can be transferred one into the other by congruence mapping. By repeating or duplicating such a contrast structure cell, the contrast structure can be scaled to any size and is therefore excellently suited for surface areas of different sizes. In particular, large-area surface elements with a contrast structure having the advantages of a completely irregular structure can be made available in a simple manner, for example on the sidewalls of vehicle tires. Since the repetition is recognizable at most at a very short distance, an excellent contrast effect is ensured for the observer. According to a preferred embodiment, the peak and trough structures, when c