HOCHBELASTBARER FAHRZEUGLUFTREIFEN, INSBESONDERE SCHLAUCHLOSREIFEN FUER LASTKRAFTWAGEN O.DGL.

摘要

A heavy duty pneumatic tire is provided with bead cores of symmetrical or asymmetrical polygonal cross-sectional. Extending radially outwardly therefrom are apex strips of a hard rubber compound which contact the bead cores along their radially outwardly oriented faces. The apex strips have a width at least as great as the width of the bead cores measured in a selected direction, and have a height of not more than 1.5 times the width of the bead cores. The terminal ends of turnups formed by wrapping a carcass ply radially about the bead cores, and reinforcement strips are enveloped in cushion elements of a rubber material which are softer than the carcass ply and the apex strips. The apex strips have a markedly compact shape cross sectionally and form with the bead cores, rigid units through which stresses occurring in the carcass during tire operation can be transferred. Residual forces in the turnups and the reinforcement strips can be absorbed readily by the cushion elements to reduce the occurrence of fatigue cracks in the beads.