To provide a plurality of conveyor belts which are disposed, with a space kept mutually in the width direction orthogonal to the longitudinal direction thereof, and capable of running along the longitudinal direction thereof in such a state that the sheet pieces with cords are placed thereon, and a lift mechanism installed between the plurality of conveyor belts to support the sheet pieces with cords on the upstream side or those on the downstream side in the longitudinal direction among the sheet pieces with cords placed on the conveyor belts while in contact with these sheet pieces from the lower side, thereby allowing them to make a relative upward movement from the sheet placing surfaces of the conveyor belts.