US Patent 9108472 Pneumatic heavy-duty tire having circumferential reinforcing layer and sipes

In the pneumatic tire, the blocks above the circumferential reinforcing layer have at least one sipe. Also, the sipe has a bent shape, in a plan view, with two flex points P1, P2, and has a closed structure with two end points Q1, Q2 terminating within the block. Also, the angle α between the line that connects the flex points P1, P2 and the tire circumferential direction is within the range such that 0°≦α≦10°. Also, the angle β1 between the line connecting the flex point P1 and the end point Q1 and the tire circumferential direction, and the angle β2 between the line connecting the flex point P2 and the end point Q2 and the tire circumferential direction are within the range such that 35°≦β1≦55° and 35°≦β2≦55°.