Disk drive apparatus

A disk apparatus comprising:

• a disk having helically-formed tracks and storing information on said tracks;
• a motor for rotating said disk;
• a pick-up means having a focus servo means and a tracking servo means for reading the information recorded on said disk by following the information stored on said tracks;
• a traverse means having a stepping motor for moving said pick-up means by a specified distance;
• a means of generating pulse signals for controlling said stepping motor;
• a means of driving said stepping motor according to said pulse signals received from said pulse signal generating means;
• a means of detecting step-up errors of said stepping motor;
• and
• a means for changing the pulse rate output from said pulse generating means to a specified pulse rate when said step-out detecting means detects a step-out in said stepping motor driving means.

A disk apparatus comprising:

• a disk having helically-formed tracks and storing information on said tracks;
• a motor for rotating said disk;
• a pick-up means having a focus servo means and a tracking servo means for reading the information recorded on said disk by following the information stored on said tracks;
• a traverse means having a stepping motor for moving said pick-up means by a specified distance;
• a pulse generating means for generating pulse signals for controlling said stepping motor;
• a stepping motor driving means of driving said stepping motor according to said pulse signals received;
• a step-out detecting means for detecting a step-out of said stepping motor;
• a step-out count storing means of storing the number of step-out times detected by said step-out detecting means;
• a driving voltage changing means for changing a driving voltage of said stepping motor according to a value stored in said step-out count storing means, said driving voltage changing means being connected to said stepping motor driving means, and
• pulse rate changing means for changing a frequency of pulses (pulse rate) output from said pulse generating means according to a value stored in said step-out count storing means.