摘要 |
PURPOSE:To provide a pneumatic tire which reduces sound pressure level due to the variable pitch arrangement method and additionally makes one quality feelings for human sense of hearing comfortable. CONSTITUTION:It is a pneumatic tire which has the tread pattern consisting of pitch trains in which a plural kinds of pitches having different length are arranged in a variable way in the peripheral direction of tire on the tread face. Pitches per periphery of tire in the pitch trains are Fourier-analyzed with rectangular wave trains which are given by arranging them at equal space and time according to the order of arrangement as original function. Amplitude AM per degree HM obtained by the Fourier analysis is distributed between the maximum amplitude curve X obtained in the equation AM=HM<->C1XC2, wherein C1=0.1, C2=1,2 and the minimum amplitude curve Y obtained with C1=10.0, C2=0.8. |