Abstract:
A pneumatic tire comprises a tread portion which is provided with a plurality of circumferential grooves extending continuously in the tire circumferential direction to axially divide the tread portion into a plurality of land portions, at least one of the land portions is provided with sipes each extending across the full width of the land portion to have a pair of open ends, each of the sipes is provided therein with at least three tie-bars to provide the bottom of the sip with at least three shallow parts in the open ends and therebetween and at least two deep parts between the shallower parts, and the depth (h2) at the shallow parts is set in the range of from 0.2 to 0.8 times the depth (h1) at the deep parts.
Abstract:
A pneumatic tire provided with a tread portion having at least one circumferential groove with an axially inner groove wall and an axially outer groove wall. The radially outer edges of the axially inner and outer groove walls incline toward the tire equator. The axially inner groove wall intersects the tread face at an inclination angle of from 25 to 45 degrees with respect to the normal line to the tread face. The axially outer groove wall intersects the tread face at an inclination angle of from 0 to 20 degrees with respect to the normal line to the tread face. The tire design reduces running noise without deteriorating aquaplane resistance.
Abstract:
A pneumatic radial tire comprises four main grooves, shoulder lateral grooves (g1L, g1R), middle lateral grooves (g2L, g2R) and central lateral grooves (g3L, g3R); the central lateral grooves (g3L) on one side of the tire equator being circumferentially shifted from the central lateral grooves (g3R) on the other side of the tire equator; the middle lateral grooves (g2L, g2R) shifted from the central lateral grooves (g3L, g3R) towards a circumferential direction (D); the shoulder lateral grooves (g1L, g1R) shifted from the middle lateral grooves (g2L, g2R) towards the circumferential direction (D); the total (WG) of the axial widths (WG1, WG2) of the four main grooves being 0.25 to 0.32 times the ground contacting area width (W); on each side of the tire equator, the width (W) and the total (LG1+LG2) of the axial length (LG1) measured from the ground contacting area edge (SE) to the axially inner edge of the shoulder rib (RS) and the axial length (LG2) measured from the ground contacting area edge (SE) to the axially inner edge of the middle rib (RM) satisfying the following relation: 0.44.ltoreq. (LG1+LG2)/W.ltoreq. 0.50.
Abstract:
A tire tread for a pneumatic tire has a center rib and a series of steeply slanted grooves in each side region of the tread, the circumferentially adjacent grooves form blocks extending through the tread side regions. The center rib has a serrated configuration along each lateral side and a supporting chamfer extending from each serration point. Adjacent to each rib chamfer is a chamfer extending from the axially innermost point of the rib at the junction of two adjacent steeply slanted grooves. The rib is provided with high density siping. The tread blocks are siped wherein the siping density decreases from the tread center to the tread shoulders.
Abstract:
A pneumatic tire, which comprises a tread portion provided with a circumferential groove having a pair of side walls, in the axial direction of the tire the circumferential groove is disposed within the ground contacting width of the tread a standard loaded state, the standard loaded state is such that the tire is mounted on its regular rim and inflated to 70% of its maximum air pressure and then loaded with 88% of its maximum load, the axial width of the circumferential groove is in the range of from 0.2 to 0.35 times the ground contacting width, and at least one of the side walls has a nonrectilinear configuration having a plurality of axially deviated parts, whereby the conditions of the resonance of the air in the circumferential groove are continuously changed during running to decrease air resonance noise there by effectively reducing the tire noise.
Abstract:
A pneumatic tire has a tread pattern defined by at least one straight circumferential groove and a plurality of lateral grooves extending from tread end toward the vicinity of a circumferential line perpendicular to a meridional line of the tire and extending slantwise and upward toward the tread end. In this tire, the lateral groove is composed of a main lateral groove portion and an auxiliary lateral groove portion. The main lateral groove portion is comprised of a steep slant segment, a dull slant segment and a curved segment smoothly connecting these slant segments and the auxiliary lateral groove portion extends substantially in parallel with the dull slant segment and opens to the tread end and the steep slant segment.
Abstract:
A pneumatic radial tire for all-season passenger car comprises a tread with a tread block pattern defined by plural slant grooves and at least one circumferential center groove and consisting of a central zone having a width corresponding to 30-60% of a tread width and a pair of side zones located on both sides of the central zone, wherein the slant grooves comprise steeply slant grooves and gently slant grooves each having a given shape, and the number of the gently slant grooves is made two times or more than the number of the steeply slant grooves, and the block is provided with at least one sipe, and each of the blocks defined by the circumferential center groove and the steeply slant grooves is chamfered from a tapered top end over a given range toward a longitudinal direction of the block.
Abstract:
A directional, symmetrical tread 12 for a tire 10 is disclosed. The tread 12 has a row 40 of elements 30, 32 which have leading and trailing edge surfaces relative to the direction of forward travel. Between the leading edge 70 of the second element and the trailing edge 74 of the first element is a tie bar 66 having a radial height which varies across the lateral width of the tie bar 66 and circumferential length of the tie bar 66.
Abstract:
A pneumatic tire has a block pattern which is divided by a center main groove extending straight on the tire equator, two outer main grooves extending straight outside the center main groove, inner lateral grooves crossing between the center and outer main grooves, and outer lateral grooves crossing between the outer main grooves and tread edges so as to make two inner block rows and two outer block rows. The outer lateral grooves cross the outer main grooves, and the inner lateral grooves cross the center main groove at an inclination opposite to an inclination direction of the outer lateral grooves.