PURPOSE: To reduce frictional force at the start of operation and to prevent a disk from breaking owing to the frictional force, by providing an auxiliary motor in addition to a main motor for rotating the magnetic disk, and performing switching to the main motor after rotating the disk at a low speed.
CONSTITUTION: In addition to a main gear 4 provided to the rotating shaft 6 of the main motor 5, an auxiliary motor gear 2 and an intermediate gear 3 are provided and low-speed rotation is used by an auxiliary motor 1. The intermediate gear 3 is inserted as shown by an arrow 12 to engage the auxiliary motor gear 2 and main gear 4, rotating the magnetic disk 7 at the low speed. Then, while the intermediate gear 3 is disengaged, the main motor 5 is only started. Thus, after the disk is rotated at the low speed by the auxiliary motor 1, switching to the high-speed rotation by the main motor 5 prevents the breaking due to frictional resistance at the start of operation.
ISHIDA SHIYOUJI
SUENAGA TADATOSHI
HAMADA MITSURU
ITOU KENICHI
