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:
Jun. 23, 2009
Filed:
May. 31, 2005
Ikuji Ikeda, Kobe, JP;
Ikuji Ikeda, Kobe, JP;
Sumitomo Rubber Industries, Ltd., Kobe-shi, JP;
Abstract
In a method for forming a green tread rubber comprised of a cap rubber layer which outer surface forms a tread surface and a base rubber layer that adjoins the same inside thereof in the radial direction, a cap rubber having a rubber component of styrene/butadiene rubber or being a mixed rubber of natural rubber and butadiene rubber is used as the cap rubber layer. The base rubber layer is formed as an annular body in which a strap-like rubber extruded body of wide width, which is extruded from a rubber extruder and is cut into constant size, is wound around a molding drum by a single round with their end portions in a circumferential direction being joined with each other. The cap rubber layer is formed as a strip layered body in which a long strap-like rubber strip of narrow width, which is extruded from an rubber extruder, is successively wound by overlapping the same on the annular body in the circumferential direction and in a spiral manner. A thickness Tof the base rubber layer on a tire equator is defined to be 0.05 to 0.7 times a thickness Tof the green tread rubber on the tire equator.