Patent ID: 6157521
Filing Date: 2000-12-05
Classification: G11B

Abstract:
A magnetic head positioning mechanism constituted by a two-stage actuator comprising:a fine actuator including a head gimbal assembly with a magnetic head provided thereon at an end thereof; anda coarse actuator supporting the fine actuator secured thereto at one end thereof, the coarse actuator having a portion adjacent the other end rotatably supported on a shaft;the fine actuator having a spring frame and a spring member provided therein and extending toward the head gimbal assembly, the spring member having an intermediate portion secured to a set pin member provided in and projecting from the coarse actuator, the fine actuator being thereby secured to and supported by the coarse actuator;a voice coil motor being provided between the fine and coarse actuators, the voice coil motor being constituted by a small coil, a yoke a and permanent magnet;the spring member of the fine actuator being flexed by a drive force generated in the fine actuator with energization of the voice coil motor small coil caused by current application thereto, thereby causing slight rotation of the head gimbal assembly in the fine actuator; andwherein the spring member consists of a pair of spring members disposed on the opposite sides of the set pin member, one of the paired spring members having a larger length than the other.