Patent attributes
A rigid core for manufacturing pneumatic tires includes a plurality of segments (2, 3), and a pair of retainer rings (5) engaging with a toroidal assembly (4) of the segments (2, 3) axially from both sides thereof, so as to hold the segments (2, 3) in the assembled state. The core defines the inner surface of the tire from formation of the tire up to the completion of the vulcanization thereof. The segments (2, 3) are each detachably divided into a center portion (2a, 3a) corresponding to the widthwise center portion of the tire and side portions (2b, 3b) corresponding to the widthwise side portions thereof. The core allows smooth removal of the segments even when the maximum inner surface width at the sidewall portion of the product tire is substantially larger than the minimum inner surface width at the bead portions thereof.