PURPOSE: To take up a strip body in a roll shape by forming an almost real circle by the upper surfaces of core constituting pieces adjacent in the circumferential direction when the core constituting pieces are pressed outwardly by a press body.

CONSTITUTION: When compressed air is injected in a press body 4 from a valve 7 thereof, a tube 12 is expanded to push out movable core materials 3 and core constituting pieces 6 adjacent in the circumferential direction are increased in diameter to form an almost real circle. A strip body 10 is taken up and air is discharged from the valve 7 after the taking-up of the strip body 10 to contract the tube 12 and the taken-up strip body 10 is detached from the core constituting pieces 6 to be supplied to the next process or delivered as a product. At the beginning of the taking-up of the strip body 10, the strip body 10 is fixed to the core constituting pieces 6 by a self-adhesive seal 11 or the end part of the strip body 10 is wound around the core constituting pieces 6 several times to be fixed to said pieces 6 or the end part of the strip body 10 is fitted in a slit 17 to be fixed. When the strip body is fixed by the self-adhesive seal 11, the strip body 10 is fixed after the press body 4 is contracted in order to separate the strip body 10 and, when a taking-up shaft 1 is reversely rotated, the self-adhesive seal 11 is easily separated from the core constituting pieces 6.