ARBITRARILY SELECTED PRIME NUMBERS TO PROVIDE PITCH SEQUENCES WITH MINIMIZED TRAVEL NOISE

摘要

ARBITRARILY SELECTED PRIME NUMBERS TO PROVIDE PITCH SEQUENCES WITH MINIMIZED TRAVEL NOISE For any given pitch sequence in the design of a tire's tread, relative pitches can be selected from a relatively small number of prime numbers arbitrarily chosen within a particular range of numbers so as to permit reasonable manipulation of the numbers in an available computer. The computer then furnishes a specific combination of pitches which combination is found to minimize travel noise for that tread design by simulating an actual test of a tire having that specific tread. A large number of combinations of variable relative pitches for a given pitch sequence in which one or more pitches might be repeated, may be evaluated by assessing string plots for each combination; thus, string plots in which the highest peaks (amplitudes) are above a preselected level are discarded as being objectionable and the large number of combinations is reduced to relatively few which may be evaluated visually or by using a computer program to choose only those string plots which have the lowest peaks and the widest distribution of the level of sound energy generated by the many pitches in the circumference of the tire's tread.