The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 09, 1999
Filed:
Jul. 07, 1997
Yasuhiko Kobayashi, Kodaira, JP;
Yuichi Nagai, Kodaira, JP;
Bridgestone Corporation, Tokyo, JP;
Abstract
A heavy duty pneumatic radial tire comprises a pair of bead portions, a pair of sidewall portions, a tread portion, a radial carcass ply and a belt, in which at least three rubber layers having different hardnesses exist in a zone ranging from the cords in a turnup portion of the carcass ply to an axially outer portion of the bead portion throughout a region of the bead portion corresponding to a line drawn normal to the axially outer portion of the bead portion in a contact area increased portion of the bead portion sandwiched between two contact end positions of an axial outside surface of the bead portion on a flange of a design rim as measured under particular conditions, and the at least three rubber layers are comprised of a coating rubber of the carcass ply and a softest rubber layer and a hardest rubber layer, and the softest rubber layer and hardest rubber layer have particular values of 100% modulus.