PNEUMATIC VEHICLE TIRES

Description

[0001] The invention relates to a pneumatic vehicle tire, in particular a commercial vehicle tire, with a tread having at least one profile rib delimited on at least one side thereof by a circumferential groove, wherein the circumferential groove, viewed in cross section, has a section running in the radial direction with a width of up to 3.0 mm and a radially inner channel region adjoining said section, wherein the radially inner channel region is delimited by two channel walls and a channel base forming the groove base and - in each case compared to the section running in the radial direction - has a larger cross-sectional area and is wider, wherein the profile rib is provided over its circumference with incisions opening into the circumferential groove, running at an angle of 0° to 50° to the axial direction and having incision walls, wherein each incision is formed by at least onethe channel opening into the radially inner channel region of the circumferential groove is locally widened, the channel being formed by a recess formed on one cut wall and a recess formed opposite this on the other cut wall.

[0002] Circumferential grooves with narrow, slit-like sections running radially and channel sections located inside the tread, which form the groove base and are significantly wider than the narrow section, are particularly advantageous for low tire rolling resistance in the central or middle tread area. As the tire rolls along the road surface, the tread ribs separated by the circumferential grooves rest against each other in the area of ​​the narrow, slit-like sections, which contributes to a reduction in rolling resistance. The channel ensures good braking properties on wet roads as the tread wears further.

[0003] A pneumatic vehicle tire of the type mentioned above, which is a commercial vehicle tire, is known, for example, from WO 2020 / 128271 A1. The tire has a tread with two profile ribs separated from one another by a circumferential groove, wherein the circumferential groove, viewed in cross-section, has a radially outer, notch-shaped section with a width of less than 3.0 mm and an adjoining radially inner channel region. The radially inner channel region is rectangular and delimited by two channel walls and a channel base forming the groove base, wherein the channel walls - corresponding to the rectangular design - are each composed of two wall sections.One tread rib is provided with axially extending cuts that open into the circumferential groove. Each of these cuts is locally widened by a channel that opens toward the tread periphery and opens into the radially inner channel area. The channel surrounds the cut inside the tread rib and is formed by depressions formed on the cut walls. The tire is designed to provide good wet performance while maintaining high tread rigidity.

[0004] DE 10 2017 208 010 A1 discloses a pneumatic vehicle tire, which is preferably a utility vehicle tire, wherein the tread of the tire has at least one circumferential groove which, viewed in cross-section, is composed of a radially outer section widening outwards in a funnel shape, a central section running in the radial direction with a width of 1.0 mm to 3.0 mm, and a radially inner channel region with a larger cross-sectional area than that in the central section. The channel region has two channel walls with radially inner wall sections which, while reducing their mutual distance from the channel base, run at an angle of 5° to 25° to the radial direction and run in a wave shape in the direction of their circumferential extent.Due to the wave shape, after appropriate tread wear, groove edges are formed on the tread periphery with a longer edge length than straight groove edges, which improves grip and braking properties on wet roads.

[0005] DE 10 2013 107 161 A1 discloses a pneumatic vehicle tire with a tread with profile ribs separated from each other by circumferential grooves designed to match the profile depth. Each groove is provided with a circumferential groove with a depth of at least 0.5 mm and no more than one-third of the profile depth. The profile rib is traversed by incisions, each of which is widened by a channel, for example, an inverted T-shaped channel, that opens into the circumferential grooves. The channel is intended to improve aquaplaning characteristics while maintaining good dry handling performance.

[0006] EP 2 644 408 A1 discloses a pneumatic vehicle tire, in particular a utility vehicle tire, with positive tread sections defined by grooves, which are traversed by incisions running in the axial direction in plan view. The incisions each open into a tubular channel running at a constant depth, on the channel base of which several dome-shaped elevations are formed. This tread is intended to have a high rigidity that is advantageous with regard to abrasion and rolling resistance, with the channels providing additional empty volume for water absorption when tread wear is sufficiently advanced. The dome-shaped elevations are intended to protect the groove base from penetrating foreign bodies, such as small stones.

[0007] DE 10 2018 208 349 A1 discloses a pneumatic vehicle tire with a tread having a shoulder-side profile rib provided with transverse grooves merging into the adjacent circumferential groove, wherein between the ends of the transverse grooves and the circumferential groove, a sawtooth-shaped incision is formed, at least over the majority of its extent, when viewed from above. Preferably, the incision terminates over its entire extent in a channel extending inside the profile rib and between the transverse groove and the circumferential groove. Under axial load, the incision blocks or limits the mutual mobility of the block-like structures of the profile rib, thereby improving the transmission of cornering forces. Under forces acting in the circumferential direction, the incision can advantageously fold open when passing through the footprint. The channel improves water drainage when driving on wet roads.

[0008] DE 10 2018 217 712 A1 discloses a vehicle tire with a tread with positive profile portions defined by circumferential grooves or diagonal grooves. These grooves are provided with cuts extending at an angle of up to 45° to the axial direction, each of which has a depression on the cut walls extending to the tread periphery. The depressions together form a channel with a channel section extending to the tread periphery and a channel section extending radially within the tread periphery and opening into at least one circumferential groove or diagonal groove. Such cuts have a good drainage effect.

[0009] DE 10 2010 017 702 A1 discloses a pneumatic passenger car tire with a tread having a shoulder-side profile rib defined by a circumferential groove and provided with transverse grooves. The rib flank adjacent to the circumferential groove is provided with flow-optimized recesses spaced from the tread periphery. Cuts run between the transverse grooves and the recesses, which open into a tunnel-shaped channel extending radially within the tread periphery between the respective transverse groove and the respective recess. The pneumatic vehicle tire is said to exhibit good aquaplaning behavior and low tire-road noise.

[0010] US 2011 / 0168311 A1 discloses a pneumatic vehicle tire with a tread having a central profile rib provided with a slit-channel network. The slit-channel network is formed from slits extending circumferentially in plan view and axially in plan view, with the slits each terminating in channels within the profile rib over their entire extent.

[0011] JP 2006 168 462 A discloses a pneumatic vehicle tire having a tread with a central tread rib bordered on both sides by a circumferential groove, which is crossed by cuts, each of which is widened by two channels running from the outer surface of the tread rib to the circumferential grooves.

[0012] In pneumatic vehicle tires of the type mentioned above, the drainage behavior of the tread, particularly in the area of ​​the tread ribs adjacent to the circumferential groove, is in need of improvement in new or slightly worn tires due to the narrow, radially extending section of the circumferential groove. This impairs tire performance on wet roads, particularly grip and braking characteristics.

[0013] The invention is therefore based on the object of further improving the drainage behavior of the tread in a pneumatic vehicle tire of the type mentioned at the outset, while maintaining the advantageous effect of the circumferential grooves on the rolling resistance of the tire.

[0014] The stated object is achieved according to the invention in that the cuts have a width of 0.4 mm to 1.2 mm and a maximum depth of 70% to 100% of the profile depth, wherein each cut on the tread periphery has a groove-shaped cut widening which runs over its entire extent in plan view and has a bottom, a depth determined in the radial direction of 10% to 30% of the maximum depth of the cut and a width of 250% to 370% of the width of the cut, wherein the channel starts from the bottom of the cut widening.

[0015] The channels formed in the sipes provide water drainage paths between the outer surface of the tread rib and the radially inner channel area of ​​the circumferential groove when the tire rolls on wet surfaces. When driving on wet roads, water absorbed from the outer surface of the tread rib is particularly effectively drained via the channels in the sipes into the radially inner channel area of ​​the circumferential groove. The beneficial effect of the circumferential grooves on the tire's rolling resistance remains unaffected.

[0016] The groove-shaped widened cut further promotes water absorption from the outer surface of the profile rib, with the water being drained away via the channels as described. The groove-shaped widened cut therefore contributes to a further improvement in drainage performance.

[0017] According to a preferred embodiment, the depth of the widened cut is 15% to 25% of the maximum depth of the cut, and the width of the widened cut is 290% to 330% of the width of the cut. According to another preferred embodiment, the channel has a circular cross-section with a diameter of 250% to 370%, in particular 290% to 330%, of the width of the cut. In such channels, the water collected when driving on wet road surfaces is particularly efficiently diverted into the circumferential groove.

[0018] Particularly preferred is a combination of the two above-mentioned designs, in which the diameter of the channel corresponds to the width of the incision widening. This improves the interaction of the channel and the incision widening with regard to the drainage effect.

[0019] A swirl-free or essentially swirl-free water flow through the channel is ensured if the channel, when viewed from the cutting wall, is semi-U-shaped.

[0020] According to a further preferred embodiment, the width of the section of the circumferential groove extending in the radial direction, which delimits the profile rib on one side, is 0.5 mm to 2.5 mm, particularly preferably from 0.8 mm to 1.2 mm.

[0021] The incisions with channels provided according to the invention are particularly advantageous when the corresponding tread rib is also bordered by a circumferential groove on its second side. The tread rib is therefore a central or middle tread rib and is located entirely within the ground contact area, so that the incisions with the channels significantly improve the drainage behavior of the tread.

[0022] In the preferred embodiment mentioned immediately above, it is advantageous if the circumferential groove, which delimits the at least one profile rib on its second side, viewed in cross-section, also has a radially extending section with a width of up to 3.0 mm and, adjoining said section, a radially inner channel region with two channel walls and a channel base forming the groove base, wherein the channel region has a larger cross-sectional area and is wider than the radially extending section, and the incisions formed in the profile rib are designed symmetrically with respect to a radially oriented cross-sectional center plane which, with respect to the longitudinal extent, runs through the center of the incision. This embodiment allows for particularly uniformly improved drainage of the profile rib.

[0023] In connection with the aforementioned preferred embodiment, it is further advantageous for drainage if a connecting channel is formed between the channels, particularly one running at a constant depth and locally widening the cut, which is spaced radially from both the tread periphery and the cut base. This connecting channel further improves drainage of the tread rib, especially when cornering on wet roads.

[0024] In the last two embodiments mentioned, it is advantageous if the width of the section of the circumferential groove extending in the radial direction, which delimits the at least one profile rib on its second side, is 0.5 mm to 2.5 mm, preferably from 0.8 mm to 1.2 mm.

[0025] A further preferred embodiment is characterized in that the circumferential groove(s), which have the radially extending section and the radially inner channel region, are provided at the junctions of the cuts with recesses that are circular in plan view, radially extending, extending to the radially inner channel region, and open to the tread periphery, with a diameter of 200% to 400%, in particular 330% to 370%, of the width of the radially extending section, wherein the recesses are each formed from indentations arranged opposite one another in pairs in the axial direction. The recesses improve the drainage of the adjacent tread ribs.In the context of solving the problem, this means that the channels in the circumferential groove and the channels in the cuts open into the radially inner channel area of ​​the circumferential groove at essentially identical "circumferential positions" of the circumferential groove. This is particularly beneficial for water drainage in the radially inner channel area of ​​the circumferential groove.

[0026] According to a further preferred embodiment, the channel walls of the radially inner channel region of the circumferential groove(s) are each composed of a radially inner wall section and a radially outer wall section, wherein the radially inner wall sections, viewed in cross-section through the circumferential groove, each run at an angle of 5° to 15°, in particular of up to 10°, to the radial direction, wherein these wall sections are inclined in opposite directions to one another in such a way that the radially inner channel region widens continuously in the axial direction from the radially inner end of the radially inner wall sections to the radially outer end of the radially inner wall sections, wherein the channel or channels which widen(s) the incision open(s) via the radially inner wall section into the radially inner channel region of the circumferential groove(s).

[0027] For the drainage of the tread, it is furthermore advantageous if the circumferential groove(s), which has / have the section running in the radial direction and the radially inner channel region, is / are composed of the section running in the radial direction, the radially inner channel region and a radially outer section widening in a V-shape towards the tread periphery.

[0028] According to a further preferred embodiment, the channel has a main axis and a radially outer channel opening, wherein the radially outer channel opening - relative to the main axis - has a distance from the circumferential groove into which the channel opens, projected into the tread periphery in the axial direction of 10% to 40%, in particular of 15% to 30%, particularly preferably of 20% to 25%, of the width of the profile rib determined at the tread periphery in the axial direction.

[0029] Furthermore, it is advantageous for the stabilization of the canal if the incisions each have an incision base and, for each canal, a base elevation adjacent to this that locally raises the incision base in the radial direction.

[0030] Further features, advantages and details of the invention will now be described in more detail with reference to the drawing, which schematically shows exemplary embodiments. Fig. 1 a simplified plan view of a circumferential section of a tread of a commercial vehicle tire with a first embodiment of the invention, Fig. 2 an enlarged top view of the detail Z 2 of the Fig. 1 , Fig. 3 a section along the line III-III of the Fig. 2 , Fig. 4 a further enlarged view of detail Z 4 of the Fig. 3 , Fig. 5 a visualization of an incision according to a second embodiment of the invention, Fig. 6 a visualization of an incision according to a third embodiment, which does not fall under the wording of the claims, and Fig. 7 a visualization of an incision according to a fourth embodiment, which also does not fall within the wording of the claims.

[0031] Pneumatic vehicle tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles, and preferably commercial vehicle tires of radial design for trucks (medium-duty trucks: 7.5 t < GVW ≤ 18.0 t, heavy trucks: GVW > 18.0 t).

[0032] Fig. 1 shows a plan view of a circumferential section of a tread of a commercial vehicle tire. The tire equatorial plane is indicated by a line AA. The tread has a central tread rib 1, two middle tread ribs 2, and two shoulder-side tread ribs 3, wherein the central tread rib 1 is separated from the middle tread ribs 2 by central circumferential grooves 4, and the middle tread ribs 2 are separated from the shoulder-side tread ribs 3 by shoulder-side circumferential grooves 5. The shoulder-side tread ribs 3 are shown only schematically and can be structured with grooves, incisions, and the like.

[0033] In the embodiment shown, the circumferential grooves 4, 5 are straight in plan view and are radially aligned to the respective intended profile depth TP ( Fig. 4 , shown for a central circumferential groove 4), which for the preferred tire type (commercial vehicle tire) is usually 12.0 mm to 26.0 mm.

[0034] The shoulder-side circumferential grooves 5 have a U-shaped cross-section (not visible) and are each delimited by a groove base 5a and two groove flanks 5b.

[0035] According to Fig. 4 the central circumferential grooves 4, viewed in cross-section and in the radial direction, are each composed of a radially outer section 4 I< , a central section 4 II< and a radially inner channel region 4 III<, whereby in the embodiment shown the sections 4 I< , 4 II< are provided with local indentations 13 running in the radial direction and formed in pairs (cf. Fig. 2 ). The design of the recesses 13 will be discussed in more detail later.

[0036] The radially outer section 4 I< widens in a V-shape towards the tread periphery, is delimited by two flanks 6 which, viewed in cross-section, run at an angle α of 30° to 50° to the radial direction, has a width b 1 of 2.5 mm to 6.0 mm at the tread periphery in the axial direction and an extension length l 1 of 10% to 30% of the profile depth TP in the radial direction. The middle section 4 II< is delimited by two flanks 7 running in the radial direction, has a width b 2 of up to 3.0 mm in the axial direction, in particular of 0.5 mm to 2.5 mm, particularly preferably of 0.8 mm to 1.2 mm, and an extension length l 2 of 30% to 60% of the profile depth TP in the radial direction.The radially inner channel region 4 III< has a larger cross-sectional area oriented in the axial direction than the middle section 4 II<, is wider than this in the axial direction, has an extension length l 3 of 30% to 60% of the profile depth TP in the radial direction and is delimited by a channel base 8 running to the profile depth TP and simultaneously forming the groove base of the circumferential groove 4, as well as by lateral channel walls 9 curved into the central profile rib 1 or the adjacent middle profile rib 2. The channel walls 9 are each composed of a radially inner wall section 9a and a radially outer wall section 9b.The radially inner wall sections 9a, viewed in cross-section through the circumferential groove 4, each extend at an angle β of 5° to 15°, in particular of up to 10°, to the radial direction, wherein they are inclined in opposite directions to one another such that the channel region 4 III< widens continuously in the axial direction from the radially inner end of the wall sections 9a to the radially outer end of the wall sections 9a. The channel region 4 III< has its widest point in the axial direction between the transitions of the radially inner wall sections 9a to the radially outer wall sections 9b, wherein this point is located from the deepest point of the circumferential groove 4 at a distance a 1 determined in the radial direction of 70% to 85% of the aforementioned extension length l 3 belonging to the channel region 4 III<. At its widest point, the channel region 4 III< has a width b 3 of 5.0 mm to 7.0 mm.

[0037] According to Fig. 1 the central profile rib 1 and each middle profile rib 2 has a width b PR determined at the tread periphery in the axial direction and is provided with a plurality of incisions 10 distributed over the circumference of the profile rib 1, 2, which in plan view run parallel to each other within the respective profile rib 1, 2, which traverse the profile rib 1, 2 and give it rib blocks 1a and 2a respectively. Fig. 2 Each incision 10 is symmetrical with respect to a radially oriented longitudinal section center plane E 1 , which runs longitudinally through the center of the incision 10. Furthermore, each incision 10 is symmetrical with respect to a radially oriented cross-sectional center plane E 2 (cf. Fig. 3 ), which runs orthogonally to the longitudinal section center plane E 1 and, with respect to the longitudinal extension, through the center of the incision 10, is symmetrically designed. The incisions 10 run - viewed in plan view and with respect to the longitudinal section center plane E 1 - to the axial direction at an angle γ of 0° to 50°, in particular of 5° to 40°, preferably of 20° to 35°, wherein the incisions 10 in the middle profile ribs 2 are inclined in the opposite direction to the incisions 10 in the central profile rib 1 with respect to the axial direction ( Fig. 1 ).

[0038] The further design of the incisions 10 is explained below using a single incision 10 formed in the central profile rib 1.

[0039] How Fig. 2 and Fig. 3 in combination, the incision 10 has an incision base 11 ( Fig. 3 ) and two opposing, radially extending incision walls 12 ( Fig. 2 ), is widened by two tubular channels 14 running to the central circumferential grooves 4 and furthermore has a groove-shaped cut widening 15 on the tread periphery. The cut 10 has between the cut walls 12 - i.e. in the area outside the channels 14 and the cut widening 15 - a width b E ( Fig. 2 ) of 0.4 mm to 1.2 mm, in particular of up to 0.8 mm, and in the radial direction at its deepest point a depth t E ( Fig. 3 ) from 70% to 100% of the tread depth TP ( Fig. 3 ). Preferably, the depth t E is at most equal to the profile depth TP reduced by 1.0 mm. The incision walls 12 are unstructured, flat surfaces in the area outside the channels 14 and the groove-shaped incision widening 15.

[0040] According to Fig. 2 The incision widening 15, viewed in plan view, runs straight and over the entire incision 10, is - in accordance with the aforementioned symmetrical design of the incision 10 - symmetrical with respect to the longitudinal section center plane E 1 and is bisected in its longitudinal extent by the cross-sectional center plane E 2. The incision widening 15, viewed in cross section, is rectangular or U-shaped, and is further characterized by two side surfaces 15b ( Fig. 3 ) and in the radial direction by a base 15a ( Fig. 3 ) and has a depth t N ( Fig. 4 ) of 10% to 30%, in particular of 15% to 25%, of the depth t E ( Fig. 3 ) of the incision 10 and a width b N determined perpendicular to the longitudinal section centre plane E 1 of 250% to 370%, in particular of 290% to 330%, of the width b E of the incision 10.

[0041] The two channels 14 are each designed symmetrically with respect to the longitudinal section center plane E 1 , with one channel 14 being designed symmetrically with respect to the other channel 14 with respect to the cross-sectional center plane E 2 ( Fig. 3 ) is formed so that one channel 14 is located in one half of the notch 10 defined by the cross-sectional center plane E 2 and the other channel 14 is located in the other half of the notch 10 defined by the cross-sectional center plane E 2 ( Fig. 3 ). According to Fig. 3 Each channel 14 starts from the bottom 15a of the cut-out widening 15, opens into the radially inner channel region 4 III< of the corresponding central circumferential groove 4, is formed by a recess 14' ( Fig. 2 ) and a recess 14' formed on the other incision wall 12 ( Fig. 2 ), is semi-U-shaped and has a circular cross-section, a main axis a K running through its center and a diameter d K of 250% to 370%, in particular of 290% to 330%, of the width b E ( Fig. 2 ) of the notch 10. The diameter d K of the channel 14 preferably corresponds to the width b N ( Fig. 2 ) of the incision widening 15.

[0042] According to Fig. 4 In the illustrated embodiment, each channel 14 is composed of a radially outer channel section 14a extending from the bottom 15a of the incision widening 15, a central channel section 14b, and a channel end section 14c, wherein the radially outer channel section 14a has a channel opening 14d located at the groove bottom 15a, and the channel end section 14c has a channel opening 14e located at the radially inner wall section 9a of the corresponding channel wall 9 of the radially inner channel region 4 III<. The channel opening 14d has - relative to the main axis a K - a distance a 2 ( Fig. 2 ) of 10% to 40%, in particular of 15% to 30%, particularly preferably of 20% to 25%, of the width b PR ( Fig. 2 ) of the middle profile rib 1.

[0043] The channel section 14a runs straight relative to the main axis a K and at an angle δ of 15° to 40°, in particular of 20° to 30°, to the radial direction. The middle channel section 14b runs in an arc shape relative to the main axis a K and is composed of four channel subsections 14b', which run along circular arcs of different radii relative to the main axis a K. The channel end section 14c runs straight relative to the main axis a K and at a depth t K determined in the radial direction of 50% to 100%, in particular of at least 60% of the depth t E ( Fig. 3 ) of the incision 10, the depth t K being adjusted accordingly to the already mentioned extension length l 3 of the radially inner channel region 4 III<.

[0044] According to Fig. 3 In the embodiment shown, the incision base 11 ends at the channels 14, wherein furthermore, adjacent to each channel 14, a base elevation 16 is formed which raises the incision base 11 in sections in the radial direction relative to the depth t E and extends up to the incision walls 12.

[0045] How Fig. 1 shows, in the case of the incisions 10 formed in the central profile rib 2, the channel 14 running further towards the outside of the tread opens into the corresponding shoulder-side circumferential groove 5 via the respective groove flank 5b.

[0046] How Fig. 2 and Fig. 4 especially in combination, the already mentioned indentations 13 formed in pairs are located at the mouths of the cuts 10 located on the central circumferential groove 4. The indentations 13 belonging to each pair form a circular recess 13' in plan view ( Fig. 2 ), which extends to the channel area 4 III< ( Fig. 4 ) and a diameter d A ( Fig. 4 ) from 200% to 400%, in particular from 330% to 370%, the width b 2 ( Fig 4 ) of the central section 4 II< of the circumferential groove 4.

[0047] Fig. 5 bis Fig. 7 show visualizations of incisions 10 I< ( Fig. 5 ), 10 II< ( Fig. 6 ), 10 III< ( Fig. 7 ), which are variants of incision 10.

[0048] The Fig. 5 The incision 10 I< shown differs from the incision 10 in that each channel 14 is composed of a continuous and uniformly curved central channel section 14f occupying the majority of the channel 14, a channel end section 14c and a radially outer channel section 14g extending to the tread periphery, formed exclusively in the region of the incision widening 15 and extending in the radial direction.

[0049] The Fig. 6 The notch 10 II< shown differs from the notch 10 I< in that there are no basic elevations 16 ( Fig. 3 ) and no incision widening 15 ( Fig. 3 ) are or are intended.

[0050] In the Fig. 7 In the incision 10 III< shown, each channel 14 is composed of five channel sections - three straight and two curved channel sections - with a straight channel section alternating with a curved channel section. Furthermore, a connecting channel 17 is formed between the two channels 14, which locally widens the incision 10 III<, runs at a constant depth determined in the radial direction and is spaced radially from both the tread periphery and the incision base 11.

[0051] The invention is not limited to the described embodiments.

[0052] The tread rib may be provided with transverse grooves that are wider than the sipes. The sipes may also be formed in shoulder-side tread ribs and each have only a single channel. Furthermore, the sipes do not have to run parallel to each other in plan view. The channel(s) may open into the respective circumferential groove at a distance determined in the radial direction from the sipe base. The radially outer section 4 I< of the circumferential groove(s), which widens in a V-shape towards the tread periphery, is optional. List of reference numbers

[0053] 1 central profile rib 1a rib block 2 middle profile rib 2a rib block 3 shoulder-side profile rib 4 middle circumferential groove 4 I< radial outer section 4 II< middle section 4 III< radial inner channel area 5 shoulder-side circumferential groove 5a groove bottom 5b groove flank 6 flank 7 flank 8 channel bottom 9 channel wall 9a radial inner wall section 9b radial outer wall section 10, 10 I< , 10 II< , 10 III< notch 11 notch bottom 12 notch wall 13 indentation 13' recess 14 channel 14a radial outer channel section 14b middle channel section 14b' channel bottom section 14c channel end section 14d channel opening 14e channel opening 14f middle channel section 14gradial outer channel section 14'Depression 15Cut widening 15aBottom 15bSide surface 16Base elevation 17Connecting channel A-A line (tyre equatorial plane) a 1 , a 2 Distance a K Main axis b 1 , b 2 , b 3 Width b E , b N Width b PR Width d A , d K Diameter E 1 Longitudinal section mid-plane E 2 Cross-section mid-plane l 1 , l 2 ,l 3 Extension length t E , t N , t K Depth TP Profile depth Z 2 , Z 4 Detail α, β, γ, δAngle,

Claims

1. Pneumatic tyre for a vehicle, in particular utility vehicle tyre, with a tread having at least one profile rib (1), which is delimited on at least one side by a circumferential groove (4), wherein the circumferential groove (4) has, when viewed in cross section, a portion (4II) running in the radial direction and having a width (b2) of up to 3.0 mm and, adjoining it, a radially inner channel region (4III), wherein the radially inner channel region (4III) is delimited by two channel walls (9) and a channel base (8) forming the groove base, and has a larger cross-sectional area and is made wider in each case than the portion (4II) running in the radial direction, wherein the profile rib (1) is provided over its circumference with sipes (10, 10I)), which merge into the circumferential groove (4), run at an angle (γ) of 0° to 50° with respect to the axial direction and have sipe walls (12), wherein each sipe (10, 10I) is locally widened by at least one channel (14) which is open to the tread periphery and merges into the radially inner channel region (4III) of the circumferential groove (4), wherein the channel (14) is formed by a depression (14') formed in one sipe wall (12) and a depression (14') formed in the other sipe wall (12), opposite the first depression, characterized in that the sipes (10, 10I) have a width (bE) of 0.4 mm to 1.2 mm and a maximum depth (tE) of 70% to 100% of the profile depth (TP), wherein each sipe (10, 10I) has, at the tread periphery, a slot-shaped sipe widening (15) which runs over its entire extent in plan view and has a bottom (15a), a depth (tN), determined in the radial direction, of 10% to 30% of the maximum depth (tE) of the sipe (10, 10I) and a width (bN) of 250% to 370% of the width (bE) of the sipe (10, 10I), wherein the channel (14) starts from the bottom (15a) of the sipe widening (15).

2. Pneumatic tyre according to Claim 1 for a vehicle, characterized in that the depth (tN) of the sipe widening (15) is 15% to 25% of the maximum depth (tE) of the sipe (10, 10I) and the width (bN) of the sipe widening (15) is 290% to 330% of the width (bE) of the sipe (10, 10I).

3. Pneumatic tyre according to Claim 1 or 2 for a vehicle, characterized in that the channel (14) has a circular cross section with a diameter (dK) of 250% to 370%, in particular of 290% to 330%, of the width (bE) of the sipe (10, 10I, 10II, 10III).

4. Pneumatic tyre according to Claims 2 and 3 for a vehicle, characterized in that the diameter (dK) of the channel (14) coincides with the width (bN) of the sipe widening (15).

5. Pneumatic tyre according to one of Claims 1 to 4 for a vehicle, characterized in that the channel (14) is half U-shaped in a view towards the sipe wall.

6. Pneumatic tyre according to one of Claims 1 to 5 for a vehicle, characterized in that the width (b2) of the radially extending portion (4II) of the circumferential groove (4) which delimits the profile rib (1) on one side thereof is 0.5 mm to 2.5 mm, particularly preferably from 0.8 mm to 1.2 mm.

7. Pneumatic tyre according to one of Claims 1 to 6 for a vehicle, characterized in that the at least one profile rib (1, 2) is likewise delimited on the second side thereof by a circumferential groove (4, 5).

8. Pneumatic tyre according to Claim 7 for a vehicle, characterized in that the circumferential groove (4) which delimits the at least one profile rib (1) on the second side thereof likewise has, when viewed in cross section, a portion (4II) running in the radial direction and having a width (b2) of up to 3.0 mm and, adjoining it, a radially inner channel region (4III) having two channel walls (9) and a channel base (8) forming the groove base, wherein the channel region (4III) has a larger cross-sectional area and is made wider in each case than the portion (4II) running in the radial direction, wherein the sipes (10, 10I) formed in the profile rib (1) are of symmetrical configuration in relation to a cross-section centre plane (E2) which is aligned in the radial direction and - with reference to the longitudinal extent - runs through the centre of the sipe (10, 10I).

9. Pneumatic tyre according to Claim 8 for a vehicle, characterized in that a connecting channel (17), which, in particular, runs at a constant depth, locally widens the sipe and is at a distance in the radial direction both from the tread periphery and from the sipe base (11), is formed between the channels (14).

10. Pneumatic tyre according to Claim 8 or 9 for a vehicle, characterized in that the width (b2) of the radially extending portion (4II) of the circumferential groove (4) which delimits the at least one profile rib (1) on the second side thereof is 0.5 mm to 2.5 mm, preferably from 0.8 mm to 1.2 mm.

11. Pneumatic tyre according to one of Claims 1 to 10 for a vehicle, characterized in that the circumferential groove(s) (4), which has or have the portion (4II) running in the radial direction and the radially inner channel region (4III), is or are provided at the entries of the sipes (10, 10I) with recesses (13') having a diameter (dA) of 200% to 400%, in particular of 330% to 370%, of the width (b2) of the portion (4II) running in the radial direction, which recesses are circular in plan view, run in the radial direction, extend as far as the radially inner channel region (4III), and are open to the tread periphery, wherein the recesses (13') are each formed by indentations (13) that lie opposite one another in pairs in the axial direction.

12. Pneumatic tyre according to one of Claims 1 to 11 for a vehicle, characterized in that the channel walls (9) of the radially inner channel region (4III) of the circumferential groove(s) (4) are each composed of a radially inner wall portion (9a) and a radially outer wall portion (9b), wherein the radially inner wall portions (9a), when viewed in a cross section through the circumferential groove (4), each run at an angle (β) of 5° to 15°, in particular of up to 10°, with respect to the radial direction, wherein they are inclined in opposite directions with respect to one another in such a way that the radially inner channel region (4III) widens continuously in the axial direction from the radially inner end of the radially inner wall portions (9a) to the radially outer end of the radially inner wall portions (9a), wherein the channel (14) or channels (14), which widens or widen the sipe (10, 10I), merges or merge via the radially inner wall portion (9a) into the radially inner channel region (4III) of the circumferential groove(s) (4).

13. Pneumatic tyre according to one of Claims 1 to 12 for a vehicle, characterized in that the circumferential groove(s) (4), which has or have the portion (4II) running in the radial direction and the radially inner channel region (4III), is or are composed of the portion (4II) running in the radial direction, the radially inner channel region (4III), and a radially outer portion (4I) widening in a V shape towards the tread periphery.

14. Pneumatic tyre according to one of Claims 1 to 13 for a vehicle, characterized in that the channel (14) has a main axis (aK) and a radially outer channel opening (14d), wherein - with reference to the main axis (aK) - the radially outer channel opening (14d) is at a distance (a2), projected into the tread periphery and determined in the axial direction, of 10% to 40%, in particular of 15% to 30%, particularly preferably of 20% to 25%, of the width (bPR) of the profile rib (1), determined in the axial direction at the tread periphery, from the circumferential groove (4) into which the channel (14) merges.

15. Pneumatic tyre according to one of Claims 1 to 14 for a vehicle, characterized in that the sipes (10) each have a sipe base (11) and, for each channel (14), a base elevation (16) adjacent to said channel and locally raising the sipe base (11) in the radial direction.