PNEUMATIC VEHICLE TIRE

Abstract

A pneumatic vehicle Eire having a tread with at least one profile block row (2, 3) which is divided into a multiplicity of profile blocks (2a, 3a) by transverse channels (6, 7) having channel flanks (7a) which extend at an angle (α, β) of up to 50° with respect to the axial direction, wherein transverse channels (6, 7) are provided, in each of which there is formed a base elevation (8, 8.sup.I) which locally reduces the depth (t.sub.1) of the transverse channel (6, 7) and which connects successive profile blocks (2a, 3a) in circumferential direction to one another, wherein the base elevation (8, 8.sup.I) has at least two base elevation parts (8a, 8b, 8c) of different height (h.sub.max, a, h.sub.max, bc).

Centrally on each of the base elevation parts (8a, 8b, 8c), there is formed at least one groove (10, 11) which runs in the dire tion of extent of the transverse channel (6, 7) and which emerges from the base elevation part (8a, 8b, 8c) at least on one side.

Claims

1.-15. (canceled)

16. A pneumatic vehicle tire comprising a tread with at least one profile block row (2, 3) which is divided into a multiplicity of profile blocks (2a, 3a) by transverse channels (6, 7) having channel flanks (7a) which extend at an angle (α, β) of up to 50° with respect to an axial direction, wherein the transverse channels (6, 7) are provided, in each of which there is formed a base elevation (8, 8.sup.I) which locally reduces a depth (t.sub.1) of the transverse channels (6, 7) and which connects successive profile blocks (2a, 3a) in a circumferential direction to one another, wherein the base elevation (8, 8.sup.I) has at least two base elevation parts (8a, 8b, 8c) of different heights (h.sub.max, a, h.sub.max, bc); and, wherein centrally on each of the at least two base elevation parts (8a, 8b, 8c), there is formed at least one groove (10, 11) which runs in the direction of extent of the transverse channels (6, 7) and which emerges from each of the at least two base elevation parts (8a, 8b, 8c) at least on one side.

17. The pneumatic vehicle tire as claimed in claim 16, wherein in a first base elevation part of the at least two base elevation parts (8b, 8c), a first groove (11) of the at least one groove extends all the way through the first base elevation part (8b, 8c).

18. The pneumatic vehicle tire as claimed in claim 17, wherein in a base elevation part (8b, 8c) with a smallest height (h.sub.max, bc) of the at least two base elevation parts, the first groove (11) extends all the way through the base elevation part (8b, 8c) with the smallest height (h.sub.max, bc).

19. The pneumatic vehicle tire as claimed in claim 16, wherein a base elevation part (8a) with a greatest height (h.sub.max, a) of the at least two base elevation parts is provided with two grooves (10) which emerge on different sides and which run in alignment with one another.

20. The pneumatic vehicle tire as claimed in claim 19, wherein the two grooves (10) which emerge on different sides of the base elevation part with the greatest height (8a) have a length (l.sub.N1), projected into the axial direction, of 20% to 40%, of a length (l.sub.a), projected into the axial direction, of the base elevation part (8a) with the greatest height.

21. The pneumatic vehicle tire as claimed in claim 19, wherein the two grooves (10) which emerge on different sides of the base elevation part with the greatest height (8a) have a length (l.sub.N1), projected into the axial direction, of at least 30%, of a length (l.sub.a), projected into the axial direction, of the base elevation part (8a) with the greatest height.

22. The pneumatic vehicle tire as claimed in claim 16, wherein the at least one groove (10, 11) has, in a radial direction, a depth (t.sub.N1, t.sub.N2) of 0.5 mm to 3.0 mm, and a width (b.sub.N1, b.sub.N2) of 35% to 50%, of a width (b.sub.1) of an associated transverse channel of the transverse channels (6, 7).

23. The pneumatic vehicle tire as claimed in claim 16, wherein the at least one groove (10, 11) has, in a radial direction, a depth (t.sub.N1, t.sub.N2) of up to 2.0 mm, and a width (b.sub.N1, b.sub.N2) of at least 40%, of a width (b.sub.1) of an associated transverse channel of the transverse channels (6, 7).

24. The pneumatic vehicle tire as claimed in claim 16, wherein a base elevation part (8a) with a greatest height (h.sub.max, a) of the at least two base elevation parts has a height (h.sub.max, a) of from 40% to 100% of a depth (t.sub.1) of an associated transverse channel of the transverse channels (6, 7), and wherein a height (h.sub.max, bc) of a base elevation part with a smaller height (h.sub.max, bc) of the at least two base elevation parts is 20% to 30% of the depth (t.sub.1) of the associated transverse channel (6, 7).

25. The pneumatic vehicle tire as claimed in claim 16, wherein a base elevation part (8b, 8c) with a smallest height (h.sub.max, bc) of the at least two base elevation parts is provided with a depression (12) which adjoins a base elevation part (8a) with a greatest height (h.sub.max, a) of the at least two base elevation parts, wherein the depression extends to channel flanks (7a), and wherein the depression has a width of 0.7 mm to 3.0 mm and a depth of 0.3 mm to 2.0 mm.

26. The pneumatic vehicle tire as claimed in claim 25, wherein the width of the depression is from 1.0 mm to 2.0 mm, and the depth of the depression is from 0.5 mm to 1.0 mm

27. The pneumatic vehicle tire as claimed in claim 16, wherein on each side of each base elevation (8, 8′) formed in the transverse channels (6, 7), a depression (9) with a width (b.sub.V1) of 0.7 mm to 3.0 mm, and a depth (t.sub.V1) of 0.3 mm to 2.0 mm, is formed on a channel base (7b) of each of the transverse channels (6, 7).

28. The pneumatic vehicle tire as claimed in claim 27, wherein the a width (b.sub.V1) is from 1.0 mm to 2.0 mm, and the a depth (t.sub.V1) is from 0.5 mm to 1.0 mm.

29. The pneumatic vehicle tire as claimed in claim 16, wherein at least one of each base elevation formed in the transverse channels is composed of two base elevation parts of different heights.

30. The pneumatic vehicle tire as claimed in claim 29, wherein the at least one of each base elevation is formed in a transverse channel (6) of a middle profile block row (2).

31. The pneumatic vehicle tire as claimed in claim 16, wherein at least one of each base elevation formed in the transverse channels is composed of three base elevation parts (8a, 8b, 8c), and wherein a middle base elevation part (8b) of the three base elevation parts is the tallest.

32. The pneumatic vehicle tire as claimed in claim 31, wherein the at least one of each base elevation formed in the transverse channels is formed in a shoulder-side profile block row (3).

33. The pneumatic vehicle tire as claimed in claim 16, wherein the at least two base elevation parts (8a, 8b, 8c) are each delimited in a radial direction by a top surface (8a′) which, in the regions that are free from the at least one groove (10, 11), runs parallel to the a periphery.

34. The pneumatic vehicle tire as claimed in claim 16, wherein the base elevation (8, 8.sup.I) has a length (l.sub.2), projected into the axial direction, of 30% to 50% of length (l.sub.1), projected into the axial direction, of the transverse channels (6, 7).

35. The pneumatic vehicle tire as claimed in claim 16, wherein on a channel base (7b) of each of the transverse channels (6, 7), there is formed a channel base channel (7c) which is narrower than the transverse channels (6, 7) and which has a depth (t.sub.1′) of 15% to 25% of a depth (t.sub.1) of the transverse channels (7) and a width (b.sub.1′) of 40% to 60% of a width (b.sub.1) of the transverse channels (7).

Description

[0019] Further features, advantages and details of the invention will now be described in more detail with reference to the drawing, which schematically shows an exemplary embodiment of the invention. In the drawing:

[0020] FIG. 1 shows a plan view of a partial development of a tread of a pneumatic vehicle tire with a design variant according to the invention,

[0021] FIG. 2 shows an enlarged plan view of the detail Z.sub.2 in FIG. 1,

[0022] FIG. 3 shows a section along the line III-III in FIG. 2,

[0023] FIG. 4 shows a section along the line IV-IV in FIG. 2,

[0024] FIG. 5 shows a section along the line V-V in FIG. 2, and

[0025] FIG. 6 shows a section along the line VI-VI in FIG. 2.

[0026] Pneumatic vehicle tires designed according to the invention are, in particular, tires of radial type of construction for passenger motor vehicles, vans or light trucks, wherein the tires are provided for driving under wintry driving conditions.

[0027] FIG. 1 shows a circumferential portion of a tread 1 of a pneumatic vehicle tire. In the exemplary embodiment shown, the tread 1 has a profiling of directional design, wherein the pneumatic vehicle tire must be installed on the vehicle so as to have the rolling direction symbolized by the arrow R during forward travel. The equatorial plane of the tire is indicated by a dashed line A-A, and the lateral edges of the ground-contacting part of the tread (corresponds to the statically determined footprint according to E.T.R.T.O. standards: load at 70% of the maximum load-bearing capacity at an internal pressure of 85% according to the E.T.R.T.O. standard) are indicated by dashed lines 1.

[0028] In each tread half, the tread 1 has a middle profile block row 2 and a shoulder-side profile block row 3. The middle profile block rows 2 are separated from one another by a central circumferential channel 4 which is straight in plan view and which runs along the equatorial plane, and from the respectively adjacent shoulder-side profile block row 3 by a shoulder-side circumferential channel 5, which in the exemplary embodiment shown runs in a straight manner in plan view. The circumferential channels 4, 5 are formed to the respectively provided profile depth T.sub.1 (indicated in FIG. 6), which is typically 6.5 mm to 10.0 mm for the preferred tire type.

[0029] Each central profile block row 2 is provided with middle transverse channels 6 running parallel to one another, and each shoulder-side profile block row 3 is provided with shoulder-side transverse channels 7 running parallel to one another, wherein the transverse channels 6, 7 extend in a V-shape across the tread width. The middle transverse channels 6 divide the middle rows of profile blocks 2 into middle profile blocks 2a and run in slightly curved form and at an angle α of 30° to 55°, in particular of at least 45°, with respect to the axial direction. The shoulder-side transverse channels 7 divide the shoulder-side profile block rows 3 into shoulder-side profile blocks 3a and likewise run in slightly curved form and at an angle β of 5° to 20° with respect to the axial direction. The angles α and β of the transverse channels 6, 7 each relate to a centerline m.sub.QR which follows the channel profile and which is therefore curved (shown in FIG. 2 for one transverse channel 7) and are measured relative to a local tangent to the centerline m.sub.QR.

[0030] A base elevation 8 is formed within the ground contact patch in each shoulder-side transverse channel 7, and a base elevation 8.sup.I is formed in each middle transverse channel 6, wherein the base elevations 8, 8.sup.I connect the respective profile blocks 2a, 3a to one another and thus locally reduce the depth of the transverse channel 6, 7. The further configuration of a shoulder-side transverse channel 7 and of a base elevation 8 will be discussed in more detail below with reference to FIG. 2 and the associated sections in FIG. 3 to FIG. 6. The differences between the base elevation 8.sup.I and the base elevation 8 will then be discussed.

[0031] According to FIG. 2 and FIG. 3, the shoulder-side transverse channel 7 has two channel flanks 7a and, in the region outside the base elevation 8, a channel base 7b with a U-shaped cross section (FIG. 3). The transverse channel 7 has, at the tread periphery, a width b.sub.1 of 5.0 mm to 8.0 mm measured perpendicularly to its centerline m.sub.QR, has, in the region of the channel base 7b, a maximum depth t.sub.1 (FIG. 3, FIG. 6) measured in a radial direction, and has, measured within the ground contact patch and based on the centerline m.sub.QR, a length l.sub.1 projected into the axial direction. The maximum depth t.sub.1 of the transverse channel 7 is 0.5 mm to 2.0 mm less than the profile depth T.sub.1(FIG. 3, FIG. 6).

[0032] According to FIG. 3, as viewed in cross section of the transverse channel 7, the channel flanks 7a run at an angle γ of 0° to 7°, in particular of 1.5° to 6°, with respect to the radial direction, wherein the angles γ of the two channel flanks 7a correspond or differ from one another, and wherein the channel flanks 7a may have chamfers, rounded portions or the like, in particular of known design, running to the tread periphery, wherein these are not taken into consideration in the measurement of the width b.sub.1 of the transverse channel 7. At the channel base 7b, there is formed a channel base channel 7c which is designed to be narrower than the transverse channel 7 and which is U-shaped as viewed in the cross section of the transverse channel 7, wherein oblique or rounded transition flanks 7d which slope downward to the channel base channel 7c run between the channel flanks 7a and the channel base 7b. The channel base channel 7c has, in the radial direction, a depth t.sub.1′ of 15% to 25% of the depth t.sub.1 and, at the radially outer end of its U-limbs, a width b.sub.1′ of 40% to 60% of the width b.sub.1 of the transverse channel 7, and, owing to the base elevation 8, is divided into a channel base channel section 7c′ at the inside of the tread and a channel base channel section 7c″ at the outside of the tread (FIG. 2).

[0033] According to FIG. 2, the base elevation 8 is composed of a base elevation part 8a, a lateral base elevation part 8b at the outside of the tread, and a lateral base elevation part 8c at the inside of the tread. At each side of the base elevation 8, there is situated a depression 9 which adjoins the respective lateral base elevation part 8b, 8c and which is formed on the channel base 7b and at which the channel base channel section 7c′ at the inside of the tread or the channel base channel section 7c″ at the tread outside ends. As shown in FIG. 6, the depressions 9, as viewed in longitudinal section of the transverse channel 7, are U-shaped and have a width b.sub.V1 of 0.7 mm to 3.0 mm, in particular of 1.0 mm to 2.0 mm, a depth t.sub.V1 of 0.3 mm to 2.0 mm, in particular of 0.5 mm to 1.0 mm, and preferably a radial spacing a.sub.1 of 1.0 mm to 2.0 mm to the level of the profile depth T.sub.1.

[0034] As is also shown in FIG. 2, the base elevation 8 has, measured at its base and based on the centerline m.sub.QR, a length l.sub.2, projected into the axial direction, of 30% to 50%, in particular of 35% to 45%, of the length l.sub.1, projected into the axial direction, of the transverse channel 7. The base elevation part 8a has a length l.sub.a, the lateral base elevation part 8b has a length l.sub.b and the lateral base elevation part 8c has a length l.sub.c, wherein the lengths l.sub.a, l.sub.b, l.sub.c are measured analogously to the length l.sub.1 of the transverse channel 7. The length l.sub.a of the base elevation part 8a and the length l.sub.b of the lateral base elevation part 8b is in each case 33% to 45% of the length l.sub.1 of the transverse channel 7, and, in the exemplary embodiment shown, the length l.sub.c of the lateral base elevation part 8c is smaller than the length l.sub.a, l.sub.b. The base elevation 8 has, based on the centerline m.sub.QR, a spacing a.sub.2, projected into the axial direction, of 2.0 to 3.0 mm to the respective shoulder-side circumferential channel 5.

[0035] According to FIG. 6, the base elevation part 8a is cuboidal and, in relation to the level of the channel base 7b (=depth t.sub.1), has a maximum height h.sub.max, a, measured in a radial direction, of 40% to 100%, in particular of 45% to 85%, and particularly preferably of at least 50%, of the depth t.sub.1. The base elevation part 8a is delimited in a radial direction by a top surface 8a′ and also by two side surfaces 8a″ running in a radial direction. Two grooves 10 are formed on the top surface 8a′, which grooves proceed from the different side surfaces 8a″, are in alignment with one another, are spaced apart correspondingly from the channel flanks 7a, and are separated by a web (FIG. 2). The grooves 10 give rise to an H shape of the top surface 8a′ as seen in plan view and in the direction of extent of the transverse channel 7 (FIG. 2), wherein the top surface 8a′ is oriented parallel to the tread periphery in the regions that are free from grooves 10. As shown in FIG. 5, as viewed in cross section of the transverse channel 7, the grooves 10 are U-shaped and have a width b.sub.N1 of 35% to 50%, in particular at least 40%, of the width b.sub.1 of the transverse channels 7, a depth t.sub.N1, measured in the radial direction, of 0.5 mm to 3.0 mm, in particular up to 2.0 mm, and a length l.sub.N1 (FIG. 2), projected into the axial direction, of 20% to 40%, in particular of at least 30%, of the length l.sub.a(FIG. 2) of the base elevation part 8a.

[0036] According to FIG. 6, the lateral base elevation parts 8b, 8c have a maximum height h.sub.max, bc relative to the level of the channel base 7b of 20% to 30%, in particular of 23% to 27%, of the depth t.sub.1. As shown in FIG. 2, centrally on each of the base elevation parts 8b, 8c, there is formed a groove 11 (FIG. 5) which has a U-shaped cross section and which is correspondingly spaced apart from the channel flanks 7a and which extends all the way through the respective base elevation part 8b, 8c in the direction of extent of the transverse channel 7 and which has a width b.sub.N2 (FIG. 4) of 35% to 50% of the width b.sub.1 of the transverse channel 7 and a depth t.sub.N2 (FIG. 4) in a radial direction of 0.5 mm to 3.0 mm, in particular of up to 2.0 mm. As shown in FIG. 6, the lateral base elevation parts 8b, 8c in the exemplary embodiment shown are provided with a depression 12 adjoining the middle base elevation part 8a, the cross section, width and depth of which depression 12 correspond to those of the depression 9, and which depression 12 extends between the channel flanks 7a and therefore between the shoulder-side profile blocks 3a.

[0037] The base elevation 8.sup.I already mentioned, which is shown in FIG. 1 and which is provided in each case in a middle transverse channel 6, is a variant of the base elevation 8. Said base elevation 8.sup.I differs from this in particular in that it is composed of only two base elevation parts, one of which is designed analogously to the middle base elevation part 8a and the other of which is designed analogously to the lateral base elevation part 8b. In the exemplary embodiment shown, each base elevation 8.sup.I has a smaller spacing to the central circumferential channel 4 than to the respective shoulder-side circumferential channel 5.

[0038] Furthermore, in the exemplary embodiment shown, at some corner regions of the profile blocks 2a, 3a, there are formed sloping corner chamfers (not designated in FIG. 1 and FIG. 2) which are designed in particular in a known manner and are not part of the invention.

[0039] The invention is not limited to the exemplary embodiments described.

[0040] For example, the base elevation part 8a may have only one of the grooves 10. The depressions 9, 12, and the channel base channel 7c running in the region outside the base elevation 8, 8.sup.I, are optional. The tire has at least one profile block row with transverse channels comprising base elevations.

LIST OF REFERENCE SIGNS

[0041] 1 . . . Tread [0042] 2 . . . Middle profile block row [0043] 2a . . . Middle profile block [0044] 3 . . . Shoulder-side profile block row [0045] 3a . . . Shoulder-side profile block [0046] 4 . . . Central circumferential channel [0047] 5 . . . Shoulder-side circumferential channel [0048] 6 . . . Middle transverse channel [0049] 7 . . . Shoulder-side transverse channel [0050] 7a . . . Channel flank [0051] 7b . . . Channel base [0052] 7c . . . Channel base channel [0053] 7c′, 7c″ . . . Channel base channel section [0054] 7d . . . Transition flank [0055] 8, 8.sup.I . . . Base elevation [0056] 8a . . . Base elevation part [0057] 8a′ . . . Top surface [0058] 8a″ . . . Side surface [0059] 8b . . . Lateral base elevation part [0060] 8c . . . Lateral base elevation part [0061] 9 . . . Depression [0062] 10, 11 . . . Groove [0063] 12 . . . Depression [0064] A-A . . . Line (equatorial plane) [0065] a.sub.1, a.sub.2 . . . Spacing [0066] b.sub.1, b.sub.1′, b.sub.V1, b.sub.N1, b.sub.N2 Width [0067] h.sub.max, a, h.sub.max, bc. Maximum height [0068] l.sub.1, l.sub.2, l.sub.a, l.sub.b, l.sub.c, l.sub.N1 Length [0069] l . . . Line (lateral edge of the ground contact patch) [0070] m.sub.QR . . . Centerline [0071] R . . . Arrow (rolling direction) [0072] T.sub.1 . . . Profile depth [0073] t.sub.1 . . . Maximum depth [0074] t.sub.1′, t.sub.V1, t.sub.N1, t.sub.N2 Depth [0075] α, β, γ . . . Angles