Heating mould for tyres

Tire heating mold with a segment ring (2), which is composed of at least six mold segments (1), which are movable in their center in the radial direction for opening and closing and have mold webs (5, 5') which form transverse grooves (8) in the tread of a vehicle pneumatic tire and are provided with flank surfaces (5b, 5'b) which are inclined in the direction of the extraction direction of the mold segment (1). Near mold segment boundaries (6), mold webs (5, 5') forming transverse grooves (8) are arranged, whose flank surfaces (5b, 5'b) located further away from the mold segment boundary (6) are inclined over at least half of their radial extension in the direction of the extraction direction (P) of the mold segment (1) at an angle (±) to the radial direction (R) which is at least 5° larger than the angle (²) at which the flank surfaces (5a, 5'a) located closer to the mold segment boundary (6) extend to the radial direction (R).