Patent classifications
B60C2011/1295
Tire Tread Comprising Complex Grooves and Incisions
A tire tread (1) having a tread pattern depth Hm, with at least two longitudinally oriented grooves (31, 41, 42), at least one of them being a complex groove (31), that in the new state, is alternately external cavities (311) that open onto the tread surface and internal cavities (312) that are hidden within the thickness of the tread. The external cavities (311) have a mean longitudinal length Lm, a depth at least equal to 0.9 Hm, and are separated by internal cavities having a mean longitudinal length Li, Li being at least equal to 0.5*Lm and at most equal to 2*Lm. At least one rib (21) in the longitudinal direction and delimited by a complex groove with transverse sipes (5) made at a mean spacing Pm. The spacing Pm of the transverse sipes is at most equal to the mean longitudinal length Lm of the external cavities (311).
Car tyre
A car tyre having a tread that extends in axial direction for a width the tread including a central portion arranged across an equatorial plane, and two lateral portions opposed with respect to the central portion. The central portion is separated from the lateral portions of the tread by two circumferential grooves. The circumferential grooves have a width greater than about 6 mm. The central portion extends in axial direction for a width less than 20% of the width of the tread and includes a plurality of first sipes. Each lateral portion has a width greater than 30% of the width of the tread, and each lateral portion includes, furthermore, a plurality of transversal grooves. The transversal grooves of a lateral portion include at least a first inclined length that extends from a zone proximal to the respective circumferential grooves, moving away from the equatorial plane. The first inclined length has an inclination α≤60° with respect to equatorial plane. Each lateral portion includes a plurality of sipes. The density of the sipes decreases moving away from the equatorial plane.
TIRE COMPRISING A TREAD
A tire comprises a directional tread (10), said tread comprising a central axis (12) and two edges (14A, 14B) a tread width W being greater than or equal to 140 mm, said tread (10) comprising a plurality of patterns (13) which succeed one another in the circumferential direction, each pattern having a pitch P, the patterns (13) delimiting a plurality of oblique grooves (16A, 16B), each oblique groove extending from one of the edges (14A, 14B) of the tread as far as the central axis (12). In a central part of the tread centered on the central axis (12) and of a width corresponding to 80% of the width W of said tread, all or some of the oblique grooves (16A, 16B) of the plurality of oblique grooves have a prescribed slenderness ratio, and all or some of the patterns comprise at least one sipe and have a prescribed sipes density SD.
PNEUMATIC TIRE
A tread pattern of a pneumatic tire includes three or more circumferential main grooves extending in a tire circumferential direction, a plurality of lug grooves provided in a land portion defined by two circumferential main grooves, and a sipe provided between adjacent lug grooves. The sipe is a composite sipe having a two-dimensional portion and a three-dimensional portion. Among open ends on both sides of the lug groove, an open end on an identical side to an end portion of the sipe at which the two-dimensional portion is provided is provided with a raised bottom portion.
Tire
In a pneumatic tire 10 according to the present invention, as an average sipe interval hc defined by an average interval of sipes adjacent to each other in a tire circumferential direction in a center portion block, which is a block arranged at a position including a tire equatorial line, and an average sipe interval hs is defined in a shoulder portion block, which is a block located at an ground contact end in a tire width direction, a relation of 1.05≤(hs/hc)≤4.00 is fulfilled.
PNEUMATIC TIRE
A tread pattern of a pneumatic tire includes two or more circumferential main grooves in a half region demarcated by the equatorial plane, and land portions defined by the circumferential main grooves. A center land portion closest among the land portions to the equatorial plane includes a center sipe extending in the width direction, the center sipe is a composite sipe including a two-dimensional portion and three-dimensional portions provided on both sides of the two-dimensional portion in the width direction, a middle land portion that is adjacent to an outer side of the center land portion in the width direction includes a middle sipe extending in the width direction, and the middle sipe is a composite sipe comprising a two-dimensional portion provided on an inner side in the width direction and a three-dimensional portion provided on an outer side of the two-dimensional portion in the width direction.
PNEUMATIC TIRE
A pneumatic tire includes a land portion defined by two circumferential main grooves extending in the circumferential direction, lug grooves in the land portion, and a sipe between adjacent lug grooves. An outer side edge of the land portion in the width direction has a zigzag shape, and an inner side edge of the land portion in the width direction has a straight shape. The sipe extends continuously from the outer side edge to the inner side edge, and the sipe has a Z-shape with two bent portions, and a ratio of a distance in the width direction between a bent portion closer to a center line passing through a midpoint position of the land portion in the width direction and the center line to a width of the land portion in the width direction being 0 to 0.40.
PNEUMATIC TIRE
A tread pattern of a pneumatic tire includes three or more circumferential main grooves extending in a tire circumferential direction, a land portion defined by the circumferential main grooves, and a sipe provided in the land portion. At least one edge of edges on both sides of the land portion in a tire width direction is a zigzag edge. The zigzag edge has a zigzag shape with recesses/protrusions that has a position periodically changing in the tire width direction. The sipe is a composite sipe including a two-dimensional portion and a three-dimensional portion, and the three-dimensional portion is connected to the zigzag edge.
Pneumatic tire
A pneumatic tire includes at least four circumferential main grooves that extend in a tire circumferential direction; and at least five land portions defined by the circumferential main grooves. The center land portion and the left and right second land portions each include through lug grooves that are inclined at a predetermined inclination angle with respect to the tire lateral direction and extend through the land portion in the tire lateral direction. The through lug grooves located in the center land portion and the through lug grooves located in the left and right second land portions extend in the tire lateral direction inclined in opposite directions to each other. At least one groove wall of each of the through lug grooves located in the left and right second land portions include a step-shaped bent portion that bends in the tire circumferential direction in a plan view of a tread.
Pneumatic tire
A pneumatic tire has an asymmetrical tread pattern and a designated vehicle mounting direction. A sipe includes a leading-side edge and a trailing-side edge, each provided with a chamfered portion shorter than a length of the sipe, and a non-chamfered region where other chamfered portions do not exist disposed in an area opposite the chamfered portion. The sipe has a maximum depth x (mm) and the chamfered portion has a maximum depth y (mm) that satisfy x×0.1≤y≤x×0.3+1.0. The sipe has a constant width in a range from an end portion of the chamfered portion positioned inward in a tire radial direction to a groove bottom of the sipe. A groove area of the chamfered portions and the sipes included within a ground contact region is greater on a vehicle mounting inner side than on a vehicle mounting outer side.