Patent ID: 6520232
Filing Date: 2003-02-18
Classification: B60C,D07B,Y10T

Abstract:
A pneumatic tire comprisinga belt disposed radially outside a carcass in a tread portion, the belt comprising two cross plies of monofilament metallic cords laid at angles of from 15 to 30 degrees with respect to the circumferential direction of the tire, each said monofilament metallic cord composed of a waved single filament, the filament having a circular sectional shape having a diameter in a range of from 0.40 to 0.50 mm, or alternatively a non-circular sectional shape having an aspect ratio in a range of from 0.65 to 0.95 and a cross-sectional area in a range of 0.09 to 0.20 sq. mm, wherein the filament has a circular sectional shape, the wave of the filament has a wave pitch of not less than 14.0 mm and a wave height of 0.002 to 0.02 times the wave pitch, each of the two cross plies has rigidity index BM in a range of from 100 to 300, wherein the rigidity index BM is defined as the product (MÃ—NÃ—L) of a bending rigidity M(gÂ·cm) of the monofilament metallic cord, a cord count N per 5 cm width of the ply, and a distance L (cm) between the cord center of one of the plies to that of the other.