Pneumatic Tire for a Vehicle

Abstract

Pneumatic vehicle tire of radial type of construction, in particular a commercial vehicle tire, having a belt assembly (3) made up of at least three plies (8, 9, 10), namely two working plies (8, 9) and a protective ply (10) arranged radially on the outside with respect to the working plies (8, 9), wherein the protective ply (10) has reinforcing members (11) made up of one or more twisted-together steel filaments (12), wherein the steel of the steel filaments (12) of the reinforcing members (11) of the protective ply (10) can be assigned to the strength class ST or to a higher strength class, wherein the strength class ST has a tensile strength in MPa of 3980-2000 d and the strength class UT has a tensile strength in MPa of 4400-2000 d, wherein d is the diameter of a steel filament in mm.

Claims

1.-6. (canceled)

7. A pneumatic vehicle tire of radial type of construction, in particular a commercial vehicle tire, having a belt assembly comprising at least three plies, wherein the at least three plies comprise two working plies and a protective ply arranged radially on the outside with respect to the working plies, wherein the protective ply has reinforcing members made up of one or more twisted-together steel filaments, and wherein the steel of the steel filaments can be assigned to a strength class; wherein steel of the steel filaments of the reinforcing members of the protective ply are assigned to the strength class ST or to a higher strength class, wherein the strength class ST has a tensile strength in MPa of 3980-2000*d and the strength class UT has a tensile strength in MPa of 4400-2000*d, wherein d is the diameter of a steel filament in millimeters; and, wherein the reinforcing members of the protective ply are steel cords of the construction 1+5×0.35 ST or cords of the construction 1+5×0.32 ST, which are arranged in the protective ply at a density of between 30 and 90 ends per decimeter (epdm).

8. The pneumatic vehicle tire as claimed in claim 7, wherein the reinforcing members of the protective ply are steel cords of the construction 1+N, where N=4 or 5.

9. The pneumatic vehicle tire as claimed in claim 7, wherein the reinforcing members are arranged in the protective ply at a density of 20 to 90 epdm.

10. The pneumatic vehicle tire as claimed in claim 7, wherein each steel filament of the reinforcing member of the protective ply has the same filament diameter, and wherein the diameter lies in a range from 0.30 to 0.45 mm.

11. The pneumatic vehicle tire as claimed in claim 7, wherein each steel filament of the reinforcing member of the protective ply has the same filament diameter, wherein the steel filament having a filament diameter in a range from 0.30 to 0.45 mm has a breaking strength in a range from 235 to 560 N, wherein the steel filament having a filament diameter in a range from 0.32 to 0.40 mm has a breaking strength in a range from 265 to 455 N, and wherein the steel filament having a filament diameter in the range from 0.32 to 0.35 mm has a breaking strength in a range from 265 to 360 N.

Description

[0024] Further features, advantages and details of the invention will now be described in more detail on the basis of the drawings, which illustrate a schematic exemplary embodiment. In the drawings,

[0025] FIG. 2 shows a partial cross section through one half of a pneumatic vehicle tire in the region of the belt and of the tread;

[0026] FIG. 3 shows a cross section through a steel cord of the protective ply of the tire in FIG. 2.

[0027] FIG. 2 shows a cross section through the tread and the belt region of a pneumatic vehicle tire for trucks having a conventional standard construction with a carcass 1 having steel cords as reinforcing members, an airtight inner layer 2, a multi-ply belt assembly 3, and a profiled tread 6.

[0028] The belt assembly 3 has four belt plies 7, 8, 9 and 10, wherein the fourth, radially outermost belt ply has the smallest width of all the plies and forms what is known as the protective ply 10. The first belt ply is what is known as the barrier ply 7, the second belt ply and the third belt ply are what are known as the working plies 8, 9. The widest belt ply is the second belt ply 8, which accordingly completely covers the first belt ply 7. The third belt ply 9 is somewhat wider than or the same width as the first belt ply 7. The fourth belt ply 10 can furthermore be embodied with the same width as the third belt ply 9. All of the belt plies 7, 8, 9, 10 consist of reinforcing members that are embedded in a rubber compound, the belt rubber coating, and consist of steel cord, wherein the steel cords are arranged parallel to one another and in a manner spaced apart from one another.

[0029] FIG. 3 shows a cross section through the protective ply 10 of the tire in FIG. 2. The protective ply 10 has steel cords 11 of the strength class ST, which are embedded in a rubber compound 15. The steel cords 11 are arranged parallel to one another and in a manner spaced apart from one another in this protective ply 10. The steel cords 11 have the construction 1×0.32 ST+5×0.32 ST, meaning that each steel cord 11 has a core filament 15 with a diameter 13 of 0.32 mm, which is surrounded by five filaments with a diameter of 0.32 mm. The cord diameter 14 is 0.96 mm. The reinforcing members 11 are arranged in the protective ply 10 at a density in a range of 30-70 ends per decimeter (epdm).

LIST OF REFERENCE SIGNS

Part of the Description

[0030] 1 Carcass [0031] 2 Inner layer [0032] 3 Belt assembly [0033] 6 Tread [0034] 7 Barrier ply (1st belt ply) [0035] 8 Working ply (2nd belt ply) [0036] 9 Working ply (3rd belt ply) [0037] 10 Protective ply (4th belt ply) [0038] 11 Reinforcing member/steel cord [0039] 12 Steel filament [0040] 13 Filament diameter [0041] 14 Cord diameter [0042] 15 Core filament