| 摘要 |
PROBLEM TO BE SOLVED: To provide a low noise type pneumatic tire having a high freedom of pattern design and suppressing eccentric wearing as much as possible. SOLUTION: The pneumatic tire has: at least one circumferential groove 1 passing through an area from a step-in end of a tread to a kick-out end on a ground-contact surface of the tire and extending along a rotation direction of the tire; and a plurality of rows of ribs 2 divided by the circumferential groove 1. A plurality of branch grooves 3 having opening ends 3a communicating with the circumferential groove 1 are formed on the ribs 2. The branch groove 3 is constituted of: a narrow wall 3b in which a groove bottom is positioned at the circumferential groove 1 side; and a wide wall 3c continued to the narrow wall 3b and rapidly enlarging the groove width of the branch groove 3. An opening shape of the branch groove 3 on a tread surface is made to be a profile shape that slowly varies from the opening end 3a to a terminal end 3d. COPYRIGHT: (C)2010,JPO&INPIT |
