Tire profile depth measurement system, for road vehicle, involves profiles formed at various depths in circumferential groove to act as wear indicators when tire rolls over test surface

摘要

The tire tread pattern includes a circumferential groove with short projecting bars at varying distances from the center of rotation. There may be different numbers of bars set at different radii. The bars cause variations in the rotational speed of the tire when it is rolled over a flat test surface. The amplitude of the rotational speed variations (I/I0) may be plotted against the frequency of the rotational speed variations (v/v0), and the resultant graph may be interpreted to give an indication of the tread wear.