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

A forming drum (1) comprises a plurality of sectors (5, 7) to define at least one deposition surface (3, 4, 6), a central body (2) connected to the plurality of sectors (5, 7) to set the sectors (5, 7) in rotation, coupling members (17) operating between each sector (5, 7) and the central body (2), wherein each coupling member (17) comprises a first element (18) movably connected to the central body (2) or to the sector (5, 7) and a second element (19) movably connected to the other among the central body (2) and the sector (5, 7), wherein the first element (18) is configured to engage a first portion (25) of the second element (19) and radially hold the sector (5, 7) to the central body (2) and disengage from the first portion (25) of the second element (19) and radially release the sector (5, 7) from the central body (2), wherein the second element (19) is configured to move between a condition in which a second portion (26) of the second element (19) locks the first element (18) and a condition in which the second portion (26) is axially distanced from the first element (18).