PNEUMATIC VEHICLE TIRE

Abstract

A pneumatic vehicle tire for utility vehicles has a profiled tread having two circumferential ribs that are adjacent and are separated by a circumferential groove of depth H formed from radially inner and outer extension sections of height H.sub.1 and H.sub.2. The groove in the radially inner extension section is a channel of height H.sub.1 and breadth B.sub.1, and in the outer extension section is configured, along its circumferential extent, with an alternating sequence of first and second circumferential regions. The two flanks in the first regions are each configured, in the transition to the outer surface of the rib, with a chamfer of height H.sub.4 such that H.sub.4<H.sub.2, and are spaced by a distance B.sub.2 along their radial extent in the outer extension section from radially inward to radially outward as far as the chamfer.

Claims

1. A utility vehicle tire having a profiled tread comprising at least two circumferential ribs that are adjacent in the axial direction A and are separated by a circumferential groove of depth H measured in the radial direction R, wherein the circumferential groove is delimited in the axial direction A by two groove walls, wherein the circumferential ribs are outwardly delimited in the radial direction R by a radially outer surface forming the road contact surface, and in the axial direction A toward the circumferential groove by a respective flank that forms a groove wall of the circumferential groove oriented toward the circumferential rib, wherein the circumferential groove is formed from a radially inner extension section of height H.sub.1 measured in the radial direction and, adjoining the latter radially, a radially outer extension section of height H.sub.2, wherein the circumferential groove in the radially inner extension section is configured as a channel of height H.sub.1 and breadth B.sub.1 measured in the axial direction A and extending over the entire circumference of the tire, wherein the radially outer extension section of the circumferential groove is designed, along its extent in the circumferential direction U, with an alternating sequence of first circumferential regions and second circumferential regions over the circumference, and wherein the radially outer extension section of the circumferential groove is designed with a maximum breadth B.sub.3 in the second circumferential regions such that B.sub.3≥B.sub.1 and with a breadth B.sub.2 in the first circumferential regions along its extent in the circumferential direction U such that B.sub.2<B.sub.1; wherein the two flanks in the first circumferential regions, which form the groove walls, are designed, in the transition to the radially outer surface of the circumferential rib, with in each case a chamfer of height H.sub.4 measured in the radial direction R such that H.sub.4≤H.sub.2, and are spaced apart from one another by a distance B.sub.2 along their radial extent in the radially outer extension section from radially inner to radially outer as far as the chamfer, wherein the two flanks in the first circumferential regions, each having the chamfer in contact with the radially outer surface of the circumferential rib, define a pair of parallel opposing chamfers; wherein the pair of parallel opposing chamfers extend in the circumferential direction U; and, wherein all chamfers comprised in the utility vehicle tire are the parallel opposing chamfers which extend in the circumferential direction U.

2. The pneumatic vehicle tire of claim 1, wherein the at least two circumferential ribs define outermost circumferential surfaces.

3. The pneumatic vehicle tire of claim 2, wherein the chamfers extend below the outermost circumferential surfaces.

4. The pneumatic vehicle tire of claim 2, wherein the at least two circumferential ribs are continuous in the circumferential direction U.

5. The pneumatic vehicle tire of claim 1, wherein all of the chamfers have a chamfer angle of greater than 30 degrees.

6. The pneumatic vehicle tire of claim 1, wherein all of the chamfers have a chamfer angle of 45 degrees.

7. The pneumatic vehicle tire of claim 1, wherein the circumferential groove has a groove bottom which varies in width along the circumferentially direction U.

8. The pneumatic vehicle tire of claim 1, wherein the at least two circumferential ribs are five circumferential ribs.

9. The pneumatic vehicle tire of claim 1, wherein the at least two circumferential ribs are four circumferential ribs.

10. The pneumatic vehicle tire of claim 1, wherein the at least two circumferential ribs are three circumferential ribs.

11. The pneumatic vehicle tire of claim 1, wherein the breadth B.sub.2 is configured such that 2.5 mm≤B.sub.2≤3 mm.

12. The pneumatic vehicle tire of claim 1, wherein the breadth B.sub.1 is configured such that 5 mm≤B.sub.1≤10 mm and the height H.sub.1 is configured such that (⅓)H≤H.sub.1≤(⅔)H.

13. The pneumatic vehicle tire of claim 1, wherein the breadth B.sub.3 is configured such that B.sub.3≤17 mm.

14. The pneumatic vehicle tire of claim 1, wherein the height H.sub.2 is configured such that (⅓)H≤H.sub.2≤(⅔)H.

15. The pneumatic vehicle tire of claim 1, wherein the height H is configured such that 8 mm≤H.sub.1≤18 mm.

16. The pneumatic vehicle tire of claim 1, wherein the height H.sub.4 is configured such that 1 mm≤H.sub.4≤3 mm.

17. The pneumatic vehicle tire of claim 1, wherein, in the second circumferential regions, the intersection contour of the two groove walls and the radially outer surface together respectively form three sides (MN, NO, OP, ST, TK, KE) and four vertices (M, N, O, P, S, T, K, E) of a shared, symmetric octagon.

18. The pneumatic vehicle tire of claim 1, wherein, in the radially inner extension section in the cross-sectional planes containing the tire axis, the groove walls are designed to be straight and to be spread apart in a V shape from radially inner to radially outer, enclosing an opening angle β such that 4°≤β≤40°.

19. The pneumatic vehicle tire of claim 9, wherein, in the radially inner extension section, the groove is bounded radially inwardly by a groove bottom which bounds the groove and has breadth B.sub.5 such that 4 mm≤B.sub.5≤B.sub.1.

20. Pneumatic vehicle tire of claim 9, wherein, in the second circumferential regions, at least in each case in a central circumferential extension region over the radial extent from the inner and radially outer extension section and as far as the radially outer surface, and in the cross-sectional planes containing the tire axis, the groove walls are designed to be straight and to be spread apart in a V shape from radially inner to radially outer, enclosing an opening angle β such that 4°≤β≤40°, and to be at a distance B.sub.3 from one another at the radially outer surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention will now be described with reference to the drawings wherein:

[0021] FIG. 1 shows a circumferential extension section of a tread profile of a utility vehicle tire in plan view;

[0022] FIG. 2 is an enlarged detail of the tread profile of FIG. 1 in plan view for the purpose of illustrating the configuration of a circumferential groove;

[0023] FIG. 3 shows the circumferential groove of FIG. 2 in a section view through line III-III of FIG. 2;

[0024] FIG. 4 shows the circumferential groove of FIG. 2 in a section view through line IV-IV; and,

[0025] FIG. 5 shows the circumferential groove of FIG. 2 in a section view through line V-V of FIG. 2.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

[0026] FIG. 1 shows a tread profile of a pneumatic vehicle tire for utility vehicles, with multiple circumferential ribs 1, 2, 3, 4 and 5 which are arranged adjacent to one another in an axial direction A of the pneumatic vehicle tire and which extend over the circumference of the pneumatic vehicle tire and which are oriented in a circumferential direction U.

[0027] In that context, circumferential ribs which are arranged axially adjacent to one another are in each case separated axially from one another by a circumferential groove. The circumferential ribs 1 and 2 are spaced apart from one another in the axial direction A by a circumferential groove 6 which extends over the entire circumference of the pneumatic vehicle tire and which is oriented in the circumferential direction U of the pneumatic vehicle tire. The circumferential ribs 2 and 3 are spaced apart from one another in the axial direction A by a circumferential groove 7 which extends over the entire circumference of the pneumatic vehicle tire and which is oriented in the circumferential direction U of the pneumatic vehicle tire. The circumferential ribs 3 and 4 are spaced apart from one another in the axial direction A by a circumferential groove 8 which extends over the entire circumference of the pneumatic vehicle tire and which is oriented in the circumferential direction U. The circumferential ribs 4 and 5 are spaced apart from one another in the axial direction A by a circumferential groove 9 which extends over the entire circumference of the pneumatic vehicle tire and which is oriented in the circumferential direction U. The circumferential ribs 1 and 5 are shoulder ribs.

[0028] The circumferential ribs 1, 2, 3, 4 and 5 are delimited toward the outside in the radial direction R of the pneumatic vehicle tire by a radially outer surface 19 which forms the road contact surface. The circumferential grooves 6, 7, 8 and 9 are delimited inwardly in the radial direction R by a groove bottom 14 which extends over the entire circumference of the pneumatic vehicle tire. The circumferential ribs 1, 2, 3, 4 and 5 are delimited in the axial direction A toward the respectively adjoining circumferential groove by a flank which forms the groove wall, respectively oriented toward the circumferential rib, of the associated circumferential groove.

[0029] FIGS. 2 to 5 illustrate the configuration of the circumferential grooves 6, 7, 8 and 9 in greater detail using the example of the circumferential groove 8. These figures show that the circumferential rib 3 bounding the circumferential groove 8 is bounded on its side facing the circumferential groove 8 by a flank 15 which extends in the radial direction R from the groove bottom 14 of the circumferential groove 8 to the radially outer surface 19 of the circumferential rib 3 and so forms the groove wall, facing the circumferential rib 3, of the circumferential groove 8. The circumferential rib 4 is bounded on its side facing the circumferential groove 8 in the axial direction A by a flank 16 which extends in the radial direction R from the groove bottom 14 to the radially outer surface 19 of the circumferential rib 4 and so forms the groove wall, facing the circumferential rib 4, of the circumferential groove 8. The circumferential groove 8 is configured with a groove depth H measured, in the radial direction R, from the radially outer surface 19 of the adjacent circumferential ribs 3 and 4 inward to the groove bottom 14. The groove bottom 14 of the circumferential groove 8 is configured with a breadth B.sub.5 measured in the axial direction A of the pneumatic vehicle tire.

[0030] The circumferential groove 8 consists, in the radial direction R, of a radially inner extension section 10 and a radially outer extension section 11. The radially inner extension section 10 extends outward in the radial direction R from the groove bottom 14 to an extension height H.sub.1 measured radially outwardly in the radial direction R from the groove bottom 14. Adjoining the radially inner extension section 10, the radially outer extension section 11 extends with an extension height H.sub.2, measured in the radial direction R, to the radially outer surface 19. In the radially inner extension section 10, the circumferential groove 8 is configured over the circumference of the pneumatic vehicle tire as a throughflow channel 10, oriented in the circumferential direction U and extending over the circumference of the tire and having extension height H.sub.1 and channel breadth B.sub.1.

[0031] The groove walls 15 and 16 in the radially inner extension section 11 in the cross-sectional planes of the tire which contain the tire axis—as shown in FIGS. 3 and 4—in each case configured inclined along their radial extent from inside to outside, in each case in the axial direction A, with respect to the circumferential rib 3 or 4 that is to be assigned to the respective groove wall 15 or 16. In that context, the groove walls 15 and 16 enclose, with one another, and opening angle β where 4°≤β≤40°, for example β=5°.

[0032] As seen over the entire circumference of the tire and in all cross-sectional planes that contain the tire axis, the groove walls 15 and 16, in the radially inner extension section 11, are configured with a distance with respect to one another that increases continuously in the radially outward direction R proceeding from the groove bottom 14, respectively enclosing the angle of inclination β, and reach their maximum separation B.sub.1, measured in the axial direction A, in the region of the radial extension end of the radially inner extension section 10.

[0033] In the radially outer extension section 11, the circumferential groove 8 is configured, along its extent in the circumferential direction U over the circumference of the tire, as an alternating sequence, arranged in series, of circumferential extension regions 12 of narrow groove breadth and circumferential extension regions 13 of large groove breadth. In the circumferential extension regions 12, the circumferential groove 8, in the radially outer extension section 11 along its extent in the circumferential direction U and along its radial extent R proceeding from the transition from the radially inner extension section 10 to the radially outer extension section 11, is configured in the radial direction to the radially outer surface 19 with a constant groove breadth B.sub.2, where B.sub.2<B.sub.1.

[0034] In the transition to the radially outer surface 19 of the circumferential rib 3, the flank 15 is configured with a chamfer 17 in the entire circumferential extension region 12. Also, in the transition to the radially outer surface 19 of the circumferential rib 4, the flank 16 is configured as a chamfer 18 in the entire circumferential extension region 12. The chamfers 17 and 18 extend in the radial direction R over an extension height H.sub.4.

[0035] As shown in FIG. 3, the flank 15 extends into the cross-sectional planes that contain the tire axis, in the radially inner extension section 10 proceeding from the radial position having the larger breadth B.sub.1 in an extension section in the axial direction A inwardly toward the other flank 16. The flank 16 also extends from the radial position of breadth B.sub.1 in an extension section in the axial direction A inwardly toward the other flank 15. In the extension section 23, the flanks 15 and 16 respectively form an axially inward axial setback of the flank 15 or 16. In that context, they respectively form, with their setback, a radially outwardly oriented closure face 23 of the radially inner extension section H.sub.1 and of the through-flow channel. As shown in FIG. 3, production dictates that this closure face 23 be inclined along its extent in the axial direction A, with a minor radial gradient. In that context, the flanks 15 and 16 extend toward one another in the axial direction A, forming the closure faces 23, as far as a separation B.sub.2 from one another that they adopt in a position at a radial distance H.sub.2 from the radially outer surface 19. From this position, the flanks 15 and 16 extend radially outward at the distance B.sub.2 from one another and form the radially outer extension section 11 having extension height H.sub.2.

[0036] In the circumferential extension sections 14, the circumferential groove 8—as shown in FIG. 4—is configured also in the radially outer extension section 11 having extension height H.sub.2 with a breadth increasing from inside to outside along its radial extent, and reaches its maximum breadth B.sub.3 in the position of the radially outer surface 19 of the circumferential ribs 3 and 4, where B.sub.3>B.sub.1. In that context, B.sub.3 is chosen such that B.sub.3≤17 mm. In that context, the circumferential groove 8, in its substantial circumferential extension section of the circumferential extension region 13—as shown in FIG. 4—proceeding from the groove bottom 14 over the radially inner extension section H.sub.1 and the adjacent radially outer extension section H.sub.2, and thus over the entire groove depth H, is configured, in those cross-sectional planes that contain the tire axis, with a straight intersection contour of the flank 15 and with a straight intersection contour of the flank 16, and thus so as to enclose the opening angle β.

[0037] As shown in FIG. 2, the flank 15 intersects the radially outer surface 19 of the circumferential rib 3 in an intersection contour which is oriented over the basic, central extension region 20 of the circumferential extension section 13 in the circumferential direction U of the pneumatic vehicle tire. The intersection contour of the circumferential extension section 14 with the radially outer surface 19 of the circumferential rib 3 is configured from this central extension section 20, a transition extension section 22 arranged immediately in front of this central extension section 20 in the circumferential direction U and a transition extension section 21 arranged immediately behind this central extension section 20 in the circumferential direction U. The transition extension section 21 connects the intersection contour of the flank 15 with the radially outer surface 19 of the basic, central extension region 20 with the intersection contour of the flank 15 with the radially outer surface 19 of the circumferential extension region 12 immediately subsequent in the circumferential direction U. The transition extension section 22 connects the intersection contour of the flank 15 with the radially outer surface 19 of the basic, central extension region 20 with the intersection contour of the flank 15 with the radially outer surface 19 of the circumferential extension region 12 immediately preceding in the circumferential direction U.

[0038] In the radially outer surface, the intersection contour in the central extension section 20—as shown in FIG. 2—extends between two points N and O. The intersection contour of the extension section 21 which extends up to a point P adjoins at point O. The intersection contour linear profile of the subsequent circumferential extension section 12 adjoins at point P. The intersection contour of the extension section 22 which extends up to a point M adjoins the intersection contour of the extension section 20 at point N. The intersection contour linear profile of the preceding circumferential extension section 12 adjoins at point M.

[0039] Similarly, the flank 16 intersects the radially outer surface 19 of the circumferential rib 4 in an intersection contour which is oriented over the basic, central extension region 20 of the circumferential extension section 13 in the circumferential direction U of the pneumatic vehicle tire. The intersection contour of the circumferential extension section 14 with the radially outer surface 19 of the circumferential rib 4 is configured from this central extension section 20, a transition extension section 22 arranged immediately in front of this central extension section 20 in the circumferential direction U and a transition extension section 21 arranged immediately behind this central extension section 20 in the circumferential direction U. The transition extension section 21 connects the intersection contour of the flank 16 with the radially outer surface 19 of the basic, central extension region 20 with the intersection contour of the flank 16 with the radially outer surface 19 of the circumferential extension region 12 immediately subsequent in the circumferential direction U. The transition extension section 22 connects the intersection contour of the flank 16 with the radially outer surface 19 of the basic, central extension region 20 with the intersection contour of the flank 16 with the radially outer surface 19 of the circumferential extension region 12 immediately preceding in the circumferential direction U.

[0040] In the radially outer surface, the intersection contour in the central extension section 20—as shown in FIG. 2—extends between two points T and K. The intersection contour of the extension section 21 which extends up to a point E adjoins at point K. The intersection contour linear profile of the subsequent circumferential extension section 12 adjoins at point E. The intersection contour of the extension section 22 which extends up to a point S adjoins the intersection contour of the extension section 20 at point T. The intersection contour linear profile of the preceding circumferential extension section 12 adjoins at point S.

[0041] Points M, N, O, P, E, K, T and S form, in the radially outer surface 19, points of an octagon that is symmetric with respect to the center line of the circumferential groove 8 formed in the circumferential direction U in the radially outer surface 19. In that context, the intersection contour of the central extension section 20 of the flank 15, together with the radially outer surface 19, forms the side NO of the octagon. The intersection contour of the extension section 21 of the flank 15, together with the radially outer surface 19, forms the side OP of the octagon. The intersection contour of the extension section 22 of the flank 15, together with the radially outer surface 19, forms the side NM of the octagon. The intersection contour of the extension section 20 of the flank 16, together with the radially outer surface 19, forms the side TK of the octagon. The intersection contour of the extension section 21 of the flank 16, together with the radially outer surface 19, forms the side KE of the octagon. The intersection contour of the extension section 22 of the flank 16, together with the radially outer surface 19, forms the side ST of the octagon. Across the circumferential groove 8, the line connecting points P and E forms the side PE of the octagon and the line connecting points M and S forms the side MS of the octagon.

[0042] In the radially outer surface 19, the sides OP and ON enclose an internal angle α. The sides ON and NM also enclose an internal angle α in the radially outer surface 19. The side KE and the side KT also enclose an internal angle α in the radially outer surface 19. The sides KT and TS also enclose an internal angle α. In that context, the angle α is configured such that 100°≤α≤140°.

[0043] In the embodiment shown, the sides NO, OP and MN are respectively chosen to have the same length. The sides TK, KE and TS are also respectively chosen to have the same length.

[0044] Along the extension of the sides NO and TK, and thus over at least half of the extension length L.sub.2, the flanks 15 and 16 thus respectively extend—as shown in FIG. 4—with an intersection line contour that is straight in the cross-sectional planes that contain the tire axis, proceeding from the groove bottom 14 to the radially outer surface 19. Along the circumferential extension sections of sides OP or MN or EK or TS, the flanks 15 and 16 extend, in the cross-sectional planes that contain the tire axis, from the groove bottom 14 through the entire radial inner extension section 10 having height H.sub.1, continuing in a straight line as far as the radially outer extension section 11 and then transition, including a kink, into a straight, radial extension section.

[0045] The breadth B.sub.1 is 5 mm≤B.sub.1≤10 mm, for example B.sub.1=7 mm. The breadth B.sub.2 is 2.5 mm≤B.sub.2≤3 mm, for example B.sub.2=3 mm. The breadth B.sub.5 of the groove bottom 14 is 4 mm≤B.sub.5≤B.sub.1. For example, B.sub.5=4 mm.

[0046] The height H is 8 mm≤H≤18 mm. The height H.sub.1 is (⅓)H≤H.sub.1≤(⅔)H. The height H.sub.2 is (⅓)H≤H.sub.2≤(⅔)H.

[0047] The height H.sub.4 is 1 mm≤H.sub.4≤3 mm.

[0048] For example, H=12 mm, H.sub.1=6 mm, H.sub.2=6 mm and H.sub.4=2 mm.

[0049] The circumferential extension regions 12 are in each case configured, as seen in the circumferential direction U in the radially outer surface, with an extension length L.sub.1 and the circumferential extension regions 13 with an extension length L.sub.2, where L.sub.1≤L.sub.2≤2L.sub.1. For example, L.sub.2=1.5 L.sub.1.

[0050] L.sub.1 is 10 mm≤L.sub.1≤50 mm.

[0051] In the radially inner extension section 10, the circumferential groove 8 is configured as a channel which extends over the entire circumference of the tire and which, in the circumferential extension sections 12, is bounded radially inwardly by the groove bottom 14 and radially outwardly by the covering faces 23 formed by the groove flanks, and in the axial direction A by those two sections of the flanks 15 and 16 that widen in a V shape between the groove bottom 14 and the covering faces 23. In the circumferential extension regions 13, the channel formed in the radially inner extension section is bounded radially inwardly by the groove bottom 14, in the axial direction A by the two flanks 15 and 16 that widen in a V shape, and is open radially outwardly.

[0052] As shown in FIG. 1, the configuration of circumferential grooves 6, 7 and 9 is analogous with that of circumferential groove 8.

[0053] In that context, FIG. 1 shows another embodiment in which, in the circumferential grooves 7 and 9, the circumferential position of the extension sections 13 is positioned between the circumferential positions of the extension sections 13 of circumferential groove 8.

LIST OF REFERENCE SIGNS

Part of the Description

[0054] 1 Circumferential rib [0055] 2 Circumferential rib [0056] 3 Circumferential rib [0057] 4 Circumferential rib [0058] 5 Circumferential rib [0059] 6 Circumferential groove [0060] 7 Circumferential groove [0061] 8 Circumferential groove [0062] 9 Circumferential groove [0063] 10 Radially inner extension section [0064] 11 Radially outer extension section [0065] 12 Narrow circumferential region [0066] 13 Broad circumferential region [0067] 14 Groove bottom [0068] 15 Flank [0069] 16 Flank [0070] 17 Chamfer [0071] 18 Chamfer [0072] 19 Radially outer surface [0073] 20 Central circumferential extension section [0074] 21 Transition extension section [0075] 22 Transition extension section [0076] 23 Closure face