To improve the productivity in a working device of a hard disk by efficiently transmitting the driving rotational force for rotating the hard disk.

While four spindles 17, 18, 19, 20 are freely rotatably provided on a rotary table 14 capable of driving the index rotation respectively at the positions keeping equal spaces along the circumferential direction, 1st and 2nd servo motors 35, 36 are provided on a supporting frame 11, then each spindle 17, 19 opposing each other and each spindle 18, 20 opposing each other are made rotatable respectively by the 1st servo motor 35 and the 2nd servo motor 36, and texture working mechanisms 48, 49 are provided at each position P2, P4.