For Controlling Noise By Varying Design Cycle (e.g., Specified Pitch Ratio, Pitch Sequence, Etc.) Patents (Class 152/209.2)
  • Publication number: 20020005236
    Abstract: A vehicle tire comprises a central tread portion divided into central blocks B0 by central oblique grooves (g); a lateral tread portion divided into four kinds of blocks B1, B2, B3 and B4 by first and second oblique grooves (ga and gb) extending from a circumferential groove (G) to a tread edge, and cross oblique grooves (gc) extending between the first oblique grooves (ga1) while crossing the second oblique groove (gb); the central oblique grooves (g) and the cross oblique grooves (gc) inclined reversely to the first and second oblique grooves (ga and gb); the number of each of the first to fourth lateral blocks B1 to B4 in each of the lateral land portions being equal to the number of the central blocks B0; and each of the first oblique grooves (ga) and two of the cross oblique grooves (gc) meeting with at axially different positions (P1 and P2).
    Type: Application
    Filed: March 13, 2001
    Publication date: January 17, 2002
    Inventor: Nobuaki Minami
  • Patent number: 6311748
    Abstract: A tread for motor-vehicle tires has a raised pattern formed of a plurality of shaped blocks 7 distributed in circumferential rows 3, 4, 5, 6 disposed in parallel and in side by side relation. The number of the shaped blocks 7 arranged in each row gradually increases while moving from the equatorial plane X—X to the axial outer side edges 1a of the tread 1. Thus a gradual increase in the longitudinal stiffness of the shaped blocks 7 is achieved on passing from the side edges 1a of the tread 1 to the equatorial plane X—X, which brings about a reduction in the mobility of said blocks on the road contact patch and lower rolling noise.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: November 6, 2001
    Assignee: Pirelli Coordinamento Pneumatici SpA
    Inventors: Maurizio Boiocchi, Gianfranco Colombo
  • Patent number: 6309026
    Abstract: A method and a device for sound suppression, in wheels, of natural frequency sound originating from an air cavity which is inside the wheel between the tire and the rim, which includes at least one resonator arranged inside the wheel. The resonator is designed for the suppression of sound resulting from the natural frequency of the wheel and is preferably formed of four quarter-wave resonators or of Helmholtz-resonators.
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: October 30, 2001
    Assignee: SAAB Automobile AB
    Inventor: Stefan Svedhem
  • Patent number: 6220844
    Abstract: There is provided a vulcanization mold for a pneumatic tire having a lug type or rib-lug type tread pattern, wherein a portion of the mold contributing to the formation of the tread pattern is comprised of many segments of n types (n=2 to 4), and these segments are combined so as to have at least (n+1) types of pitches each defined by an interval between mutual adjoining protrusions located on the same circumference and a difference between mutual pitches of not less than 0.5 as an index when a maximum value of the pitch is 10.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: April 24, 2001
    Assignee: Bridgestone Corporation
    Inventor: Akio Kusano