Patent ID: 7221543
Filing Date: 2007-05-22
Classification: G11B

Abstract:
1. A two-stage actuator type magnetic head positioning mechanism comprising: a plurality of fine actuator sections which minutely drives, by a pair of piezo-electric elements mounted in said fine actuator sections, a magnetic head supporting section adapted to support a slider on which a magnetic head is attached; a plurality of holder arms to support each of said fine actuator sections; an arm block formed by integrally unifying said plurality of holder arms; and a voice coil motor to drive said arm block; wherein said fine actuator section is composed of an actuator spring made from one thin steel plate and a base plate made from one thick steel plate, both of which overlap each other, said magnetic head supporting section and said actuator spring being formed separately from one another, wherein a driving spring section comprised of a pair of side springs extending perpendicularly to a center axis of the actuator spring, and a center spring disposed on the center axis of the actuator spring, the driving spring section being connected to said magnetic head supporting section and mounted on said actuator spring and, in a vicinity of said driving spring section, a pair of driving voids are disposed, with the center axis of the actuator spring therebetween, to absorb vibration of said magnetic head supporting section and extension/shrinkage of said pair of piezo-electric elements, each disposed over a corresponding void of said voids, in response to voltage-induced changes in the driving spring section, wherein end portions of said pair of piezo-electric elements are connected to said magnetic head supporting section and to said actuator spring, respectively, in a manner such that said end portions of each piezo-electric element straddle the corresponding void of said driving voids without overlapping a non-corresponding void of said driving voids, and wherein said base plate is junctioned to one face of said actuator spring in a manner such that said base plate covers said pair of driving voids.