Pneumatic tires with recesses in the bead region

Abstract

A pneumatic tire involves a toroidal carcass ply extending between a pair of beads. The carcass ply consists of a main body located axially inside the beads and a pair of outer ply portions each extending along the main body of the carcass ply and on an axially outer side of the bead. A recess is provided on an outer surface of the tire between a radially outer end of each of the outer ply portions of the tire and the tire maximum width location such that a part of the recess is located in a zone surrounded by a curve C--C, a curve D--D, and an E-axis. The curve C--C satisfies d/s=1-0.825.times..sqroot.2.64-(h/s), and the curves C--C, and D--D, the E-axis, d, s, h are defined as follows: a widthwise center line of the main body of the carcass ply being taken as A--A; a curve passing through the radially outer end of the outer ply portion and being parallel with the curve A--A being taken as B--B; an axis lying on the curve B--B and extending from the radially outer end of the outer ply portion toward the location having maximum width being taken as an H-axis; an axis extending from the radially outer end of the outer ply portion toward an interior of the tire in a direction orthogonal to the H-axis being taken as the E-axis; a distance from an origin as measured along the E-axis extending the radially outer end of the outer ply portion toward the interior of the tire in a direction orthogonal to the H-axis being taken as d, the origin being an intersection between the E-axis and the H-axis; a distance from the radially outer end of the outer ply portion to the center line A--A as measured on the F-axis being taken as s; a distance from the origin as measured along the H-axis being taken as h; and the curve D--D being a curve extending between the curves A--A and B--B and being parallel with the center line A--A, while being spaced from the center line A--A by 1/3s.