Block structure in pneumatic tire

摘要

A block structure in a ground contact face of a tread portion of a pneumatic tire comprises blocks defined by circumferential grooves and lateral grooves and a sipe formed in each surface of the blocks in a block row at least located near to a center of the tread and opening at least one end thereof to the respective circumferential groove, in which the sipe is opened through a width-widened part to the circumferential groove and a depth of the width-widened part is made shallower than a depth of a deepest part of the sipe.