Method and apparatus for detecting tire information mark

A method of detecting tire information marks provided on a side wall portions of tire in the form of a protrusion or a recess comprising the steps of:

• detecting an identification mark provided on the side wall portion of tire separately from the tire information marks, at a fist detecting stage with the aid of a first detector head to derive a position signal representing both circumferential and radial directions of the information marks;
• transporting the tire from said first detecting position into a second detecting position, while the attitude of the tire is kept substantially unchanged;
• positioning at least in circumferential and radial directions of the tire a second detector head provided at the second detecting position in accordance with said position signal;
• and
• detecting the tire information marks with the aid of said detector head.