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. 25, 2002
Filed:
May. 28, 1996
Chishiro Tanabe, Kodaira, JP;
Yuji Yamaguchi, Kodaira, JP;
Bridgestone Corporation, Tokyo, JP;
Abstract
A studless pneumatic tire having excellent running performance of the tire on icy road surfaces. The tire has a plurality of block-shaped island portions formed on a cylindrical tread extending between a pair of sidewalls. The island portions have laterally extending sipes and are separated by a plurality of main grooves extending in the circumferential direction as well as by many lug grooves. Each island portion has a first sipe and a second sipe. The first sipe extends from a first lateral end facing a first main groove to traverse a first edge region of the island portion in a substantially axial direction and branches into a plurality of branch segments, thereby forming a fork-like shape, at a first interface between the first edge region and the central region of the island portion. Each branch segment traverses the central region of the island portion and reaches a point near a second interface between an opposite second edge region and the central region of the island portion. The second sipe extends from a second lateral end of the island portion facing a second main groove so as to traverse the second edge region and extends into the central region of the island portion in the axial direction. These first and second sipes divide the central region of the island portion into a larger number of island elements compared to the edge regions of the island portion.