Abstract: A tread pattern of tire tread is formed by an alignment (sequence) of pattern composing units of s types different in pitch P that is a circumferential length. The pattern composing units are allocated to sections of the axes of abscissa and ordinate from the origin in the order of lower pitch P. Out of all regions present in a certain section of the axis of abscissa and aligned in the longitudinal direction, a defined region defining a chaotic function is determined for respective sections of abscissa. The chaotic function is represented by X(n+1)=fc(Xn), where Xn is the axis of abscissa, and X(n+1) the axis of ordinate. An alignment of pattern composing units is obtained according to a sequence of numbers sequentially obtained by the chaotic function. The alignment of pattern composing units is further verified before employment. In such manner, discomfort due to noises caused by a tire during a travel is reduced.

Abstract: A pneumatic tire comprises a radially inner bead core disposed in at least one of the bead portions, a radially outer bead core disposed radially outside the inner bead core, a buffer rubber layer disposed between the radially inner bead core and radially outer bead core to provide a predetermined space therebetween, and a toroidal carcass extending between the bead portions through the tread portion and sidewall portions, wherein the carcass comprises a ply of cords turned up around the radially outer bead core to be secured thereto, passing between the radially outer bead core and the buffer rubber layer, so that a radially outward tension of the carcass caused by tire inflation acts less on the radially inner bead core than the radially outer bead core.

Abstract: A low noise tire having circumferentially spaced tread grooves each having a paired groove spaced apart therefrom by a distance substantially the same as the circumferential length of a ground contacting region of the tread when the tire is mounted on a regular rim and inflated to a normal internal pressure and loaded with a normal load, whereby pattern noise can be suppressed.

Abstract: A pneumatic tire has a tread pattern with blocks which are divided by two circumferential grooves extending in the circumferential direction of a tire and eighty-five or more lateral grooves crossing the circumferential grooves in a tread part. In the tread pattern, the quotient S.sub.T /S of the total groove area S.sub.T which is the sum of the circumferential groove area S.sub.G and the lateral groove area Sg in a ground contact surface S when the tire is mounted on a standard rim, inflated with a normal internal pressure and loaded with a normal load, to the ground contact area S is in a range from 0.15 to 0.25, and the rate Sg/S.sub.G of the lateral groove area Sg to the circumferential groove area S.sub.G is in a range from 0.33 to 0.53.

Abstract: A pneumatic radial tire for automobiles having a belt of steel cords and an organic cord reinforcement structure radially outward of the belt. The tire has improved uniformity and low vibration during high speed running due to the relative circumferential location of the joint in the tread layer, the joint in the full band reinforcement layer and the joint in the edge band which surrounds the belt.

Abstract: A pneumatic tire has a block pattern which is divided by plural circumferential grooves extending in the circumferential direction of a tire and a number of lateral grooves crossing the circumferential grooves. In the block pattern, the block circumferential/lateral ratio Lm/Wm of the average block circumferential length Lm to the average block width Wm is in a range from 0.38 to 0.55, and the block circumferential length ratio Lm/L of the average block circumferential length Lm to the circumferential length L of the tread part is in a range from 1/120 and to 1/85.