Band detaching method in band building drum and band building drum

A band detaching method in a band building drum, including an expandable and contractable cylindrically shaped band building drum having a plurality of first segments and a plurality of second segments disposed alternately and circumferentially to form the cylindrical shape of the band building drum, the band detaching method comprising the following steps in order:

• bringing the respective segments into a diametrically expanded state for the band building to be carried out, and after that then;
• building the band around an outer circumferential surface of the expanded segments and after that then;
• diametrically contracting the first segments from the diametrically expanded state while holding the second segments in the diametrically expanded state and after that then;
• temporarily returning the first segments to the diametrically expanded state while holding the second segments in the diametrically expanded state, and then after that diametrically contracting the second segments from the diametrically expanded state while holding the first segments in the diametrically expanded state, so that the band is peeled off from being in close contact with the outer circumferential surface of the segments;
• and then after that
• detaching the band by bringing both of the first and the second segments into a diametrically contracted state.