Disk device

A disk device comprising:

• a head;
• a disk having a recording surface;
• a motor that causes the head to seek along the recording surface;
• and
• a controller that controls the motor, wherein
• the controller, when a rotation waiting time is absent from when the head reaches a target track of the disk to when the head reaches a target sector, increases an absolute value of a motor current in a first section in a first period in which the head is accelerated or decelerated, changes the absolute value of the motor current at a first average change rate in a second section after the first section in the first period, and decreases the absolute value of the motor current at a second average change rate that is steeper than the first average change rate in a third section after the second section in the first period, and
• the controller, when the rotation waiting time is present, increases the absolute value of the motor current in a fourth section in a second period in which the head is accelerated or decelerated, changes the absolute value of the motor current at a third average change rate in a fifth section after the fourth section in the second period, decreases the absolute value of the motor current at a fourth average change rate steeper than the third average change rate in a sixth section after the fifth section in the second period, and decreases the absolute value of the motor current at a fifth average change rate steeper than the fourth average change rate in a seventh section after the sixth section in the second period.