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:
Oct. 31, 1978
Filed:
Mar. 15, 1977
Hiroyoshi Takigawa, Higashi-Murayama, JP;
Shigeo Watanabe, Kokubunji, JP;
Shigeta Aoki, Higashi-Murayama, JP;
Hiroshi Ogawa, Kodaira, JP;
Bridgestone Tire Company Limited, Tokyo, JP;
Abstract
A heavy duty pneumatic radial tire having tread patterns divided into a central zone and peripheral zones by two main continuous zigzag grooves spaced apart a distance 25-38% of the overall width of the tread and having a main groove oblique or zigzag angle of 55-78.degree. relative to a radial plane of the tire. Each of the peripheral zones is divided into the form of arrow feathers by traverse grooves having walls tilted through at least 20% of the depth of the traverse groove at an angle within 20-40.degree. to a center line of the traverse groove. The ratio of total areas of the central zone to those of one of the peripheral zones is 1:1.0 to 1:1.5, and the ratio of the total areas of inner and outer peripheral blocks in the peripheral zones divided by a continuous zigzag groove substantially parallel with the main grooves is 1:1.5 to 1:2.5, thereby greatly mitigating ununiform wear at the shoulders of the tread, heal-and-tow wear between front and rear edges of blocks defined by the grooves in the pattern, and railway wear at the edges of the blocks in opposition to the grooves.