Patents Examined by Laurence E. Williams
  • Patent number: 4114671
    Abstract: A pneumatic tire for vehicles has a tread band provided with grooves which extend circumferentially about the tire. The grooves are formed by a series of substantially rectilinear sections which are disposed at a predetermined angle with the equatorial plane of the tire and intersect to impart a zig-zag arrangement to the grooves about the tire. The intersections between said groove sections are situated in planes parallel to the equatorial plane of the tire, and each tread surface portion between one of the parallel planes and a pair of adjacent sections of a groove is shaped so the distance at its points from the tire axis gradually decreases from the parallel plane toward the region in which the sections of the pair of adjacent sections intersect.
    Type: Grant
    Filed: January 11, 1977
    Date of Patent: September 19, 1978
    Assignee: Industrie Pirelli S.p.A.
    Inventors: Luigi Maiocchi, Luigi Silva