FORMING DRUM FOR PRODUCING TYRES FOR VEHICLE WHEELS AND METHOD FOR CONTROLLING THE GEOMETRY OF A FORMING DRUM FOR PRODUCING TYRES FOR VEHICLE WHEELS

The invention describes a forming drum (1) for producing tyres for vehicle wheels comprising a central shaft (2), two lateral deposition surfaces (3, 4) axially opposite and set in rotation by the central shaft (2), an adjustment linkage (17), configured to axially move the two lateral deposition surfaces (3, 4) and comprising an adjustment shaft (18), at least one actuation device (25) fixedly connected to the adjustment shaft (18) and at least one locking device (26) operating on the actuation device (25) between a first condition in which it prevents the rotation between the actuation device (25) and the central shaft (2) and a second condition in which it allows the rotation between the actuation device (25) and the central shaft (2). The locking device (26), in the first condition, defines a plurality of locking positions for the actuation device (25), wherein any locking position is reachable by the actuation device (25), starting from a previous locking position, following a predetermined rotation between the actuation device (25) and the central shaft (2) with the locking device (26) in the second condition.