Abstract: A disk (6) is horizontally rotated a half-turn by a motor (7) in a rotational direction and, then, is rotated a half-turn in an opposite rotational direction. Two servomotors (8, 9) are symmetrically disposed, on an upper surface of the disk (6), with respect to a rotating shaft of the disk (6). Driving shafts (22, 23), driven by the two servomotors (8, 9), downwardly extend through the disk (6), and move hanging members (K, M), respectively, in upward-and-downward directions. Two hanging members (K, M) are provided, at their lower ends, with clampers (32), respectively. The clampers (32) are each provided, at their bottom surfaces, with a suction pad (35), and are provided, at their upper surfaces, with pneumatic cylinders (28, 29). The pressure of the compressed air supplied to the pneumatic cylinder is adjusted by a pressure regulating device (38).

Abstract: A disk (6) is horizontally rotated a half-turn by a motor (7) in a rotational direction and, then, is rotated a half-turn in an opposite rotational direction. Two servomotors (8, 9) are symmetrically disposed, on an upper surface of the disk (6), with respect to a rotating shaft of the disk (6). Driving shafts (22, 23), driven by the two servomotors (8, 9), downwardly extend through the disk (6), and move hanging members (K, M), respectively, in upward-and-downward directions. Two hanging members (K, M) are provided, at their lower ends, with clampers (32), respectively. The clampers (32) are each provided, at their bottom surfaces, with a suction pad (35), and are provided, at their upper surfaces, with pneumatic cylinders (28, 29). The pressure of the compressed air supplied to the pneumatic cylinder is adjusted by a pressure regulating device (38).