Magnetic crash stop and latch in a disc drive

Abstract

A magnetic crash stop and latch for limiting the motion of a transducer positioner assembly within a disc drive. The disc drive system has a transducer positioner assembly located within a housing for positioning one or more read/write transducers relative to a recording media within the housing. The apparatus includes components for latching an actuator assembly in a disc drive. A parking force is created by selectively attaching a small magnet (or one or two small ferrous metal slugs) to the end of the actuator arm portion of the actuator assembly having the voice coil motor (VCM). The small magnet (or slugs) operating in combination with the fixed magnetics of the VCM produces torque on the actuator assembly when the small magnet passes outside (or the slugs pass inside) of the magnetic field generated by the fixed magnetics. The resultant torque is utilized to move the actuator arm to contact a latch means. The latch means is preferably a ramp, but may be a magnetic latch created by the two slugs, mechanical latch, or a combination using both magnetic and mechanical apparatus as is known in the art. The magnet or slug is positioned so that it does not affect the normal torque or forces that are used to move the arm.