Patent ID: 7972195

Claim:
A tire grinding method comprising: when a tire to be retreaded is loaded to a holding mechanism of a grinding device and a tread portion of the tire to be retreaded that is rotated by the holding mechanism about a device axial center is to be grinded by grinding means, detecting, with a metal detection sensor, along a rotating direction whose center is the device axial center, a distance from the device axial center to a metal belt layer of the tire to be retreaded that is held by the holding mechanism, and thereafter causing the grinding means to relatively move with respect to the tire to be retreaded along a radial direction whose center is the device axial center on the basis of a position along a rotating direction of the tire to be retreaded and detected value of the distance from the device axial center to the belt layer, and grinding, with the grinding means, the tread portion of the tire to be retreaded that is rotated by the holding mechanism, wherein when the tire to be retreaded is grinded by the grinding means, the grinding means is relatively moved along the radial direction, such that a distance from a center of curvature of the belt layer of the tire to be retreaded to the grinding means becomes constant, on the basis of the position along the rotating direction of the tire to be retreaded and the detected value of the distance from the device axial center to the belt layer that is detected by the metal detection sensor.