Patent ID: 6601623
Filing Date: 2003-08-05
Classification: B60C,Y10S

Abstract:
A pneumatic tire provided with a tread divided into a plurality of block-shaped land portions, the periphery of each of said block-shaped land portions being bordered by a plurality of main grooves extending in the circumferential direction of said pneumatic tire, and by a plurality of lug grooves extending in the transverse direction of said pneumatic tire and intersecting said main grooves, and each of said block-shaped land portions having at least four sipings aligned in a transverse direction, each of said sipings comprising:a first linear portion which essentially extends in a direction perpendicular to the surface of said block-shaped land portion and contacts the tread surface; a second linear portion which essentially extends in a direction perpendicular to the surface of said block-shaped land portion and is separated from the surface of said block-shaped land portion; and a sloping line portion which connects said first linear portion and said second linear portion and is inclined in a direction towards a wall surface of said block-shaped land portion, so as to define a step, wherein a position of a center of said sloping line portion is set to between 10% to 60% of the siping depth measured from said tread surface; and wherein the position of the sloping line portions of the outer sipings on the block-shaped land portions is at a shallower depth than the position of the sloping line portions of the inner sipings.