PURPOSE: To easily correct timing shifts caused by center shifts between a driving mechanism and an angle detecting sensor by providing a variable delaying means for generating a specified time passage reference position signal from a position signal.
CONSTITUTION: A position signal generating magnet 31 attached to the rotary part of a FDD generates a position signal by passsing the front of a magnetic sensor 32 fixed to a FDD frame for every rotation. In a FD 10, a reference angle position A for generating an index signal is predetermined according to a standard. An angle position for generating a position signal is set so as to advanced by an angle T to the reference angle position A. A delaying circuit is provided for outputting the index signal delayed by time equivalent to the angle T from the position signal. A standard disk is attached to the FDD, the delay of the standard index signal is counted from the position signal, and by setting delayed time on the counted value with, for instance, a digital switch timing shifts are corrected.
SEO YUZO
YOSHIYAMA RYUICHI
