Magnetic disk drive piezoelectric actuator with hinge plate limbs extending non-linear symmetrically from central portion

An information storage device, comprising:

• a head section carrying a head which executes at least one of information recording and information reproduction on/from a predetermined information storage medium;
• an arm section which holds the head section in order for the head mounted on the head section to approach or contact the information storage medium;
• an arm actuator which drives the arm section to move the head mounted on the head section held by the arm section over the information storage medium;
• and
• a head actuator which rotates the head section with respect to the arm section, wherein
• the head actuator comprising:
• a hinge plate which has a central portion, two lateral portions, and two limbs, the central portion having both ends and being allowed to be divided between both the ends, the two lateral portions extending point-symmetrically from both ends of the central portion, and the two limbs extending point-symmetrically and non-linear symmetrically from both ends of the central portion such that the central portion is disposed between the two limbs and being capable of bending toward and away from the lateral portions;
• and
• a piezoelectric element to which the two limbs of the hinge plate are attached firmly and which brings the two limbs toward and away from each other when it expands or contracts by application and removal of voltage.