Information storage device capable of oepration in a velocity control mode and a tracking control mode

An information storage device capable of operation in a velocity control mode and a tracking control mode and comprising:

• a head having a carriage and a tip, for recording, reproducing and erasing information on and from an information storage medium having multiple tracks;
• a tracking actuator for moving said tip of the head in a track-traverse direction;
• a head actuator for driving said carriage in said track-traverse direction so that said tip of the head traverses the tracks;
• track control means for controlling, in said tracking control mode, the tracking actuator so that said tip of the head follows the center of a track;
• off-track detecting means for detecting the departure of said tip of said head from the track;
• means for controlling, in said velocity control mode, the head actuator such that the velocity with which said tip of said head traverses the tracks is reduced to a relatively small value;
• and
• mode switching command generation means for switching control of said tip of said head between said velocity control mode and said tracking control mode;
• wherein when said off-track detection means detects said departure during tracking control mode, said mode switching command generation means switches to said velocity control mode, and when the track traverse velocity is reduced to the small value said mode switching command generation means switches to said tracking control mode.