Patent ID: 6259661
Filing Date: 2001-07-10
Classification: G11B

Abstract:
A disk reading apparatus for reading data recorded on a disk medium, comprising:a motor for rotating the disk medium;a vibration sensor section for detecting vibrations generated inside the disk reading apparatus and for converting the vibrations into a signal;a binarized signal generation section for extracting only a frequency component corresponding to the rotary speed of the disk medium from the signal outputted from the vibration sensor section, and for outputting a signal in which a binarization is performed;a vibration judgement section for:measuring a period of the binarized signal outputted from the binarized signal generation section to distinguish between the vibrations resulting from an eccentricity of the disk medium and the vibrations caused by external impact; andoutputting a vibration detection signal when the period of the binarized signal corresponds to the vibrations resulting from the eccentricity of the disk medium; anda rotation control section for lowering the rotary speed of the disk medium when the vibration detection signal is inputted.