TREAD THICKNESS MEASUREMENT METHOD

摘要

To provide a tread thickness measurement method with which it is possible to measure with good precision the thickness of a tread with ultrasound measurement from a belt surface located in the outermost part of a tire to a tread surface irrespective of the material of the belt, a tread thickness measurement method comprises: a shape measurement step of measuring the outer shape of the tread surface; a groove bottom location identification step of identifying, from the outer shape which is obtained by the shape measurement step, the groove bottom of a groove which extends in the tire circumference direction; a depth estimation step of estimating the depth from the groove bottom to the belt surface, said estimation being based on the groove bottom which is identified by the groove bottom identification step, and being based on pre-created tire design data; a thickness prediction step of computing a predicted thickness from the tread surface to the belt surface from a relation between the thickness from the groove bottom which is identified by the groove bottom location identification step to the tread surface in the outer shape and the depth from the groove bottom to the belt surface which is estimated by the depth estimation step; and an amplification rate setting step of setting an amplification rate of received reflected waves via a reflection rate-thickness data map which is pre-set according to the predicted thickness.