Patent ID: 6344950
Filing Date: 2002-02-05
Classification: G11B

Abstract:
A head disk assembly, comprising:a disk having a recording surface surrounded by an outer circumference; a head stack assembly having an actuator pivot axis and including a head gimbal assembly; the head gimbal assembly including a gimbal defining a gimbal axis parallel to and spaced a first distance from the actuator pivot axis, and including a lift tab having a lift-surface portion spaced a second, larger distance from the actuator pivot axis; a ramp-defining structure including: a wall extending parallel to the actuator pivot axis; an axis-defining portion defining a retraction pivot axis; a shelf projecting from the wall to define a bearing surface against which the lift-surface portion slides during unloading and loading operations; the bearing surface having a meandering and undulating shape to define a retention portion and a cam portion; the retention portion defining a first arc that is centered about the retraction pivot axis, and the cam portion defining a second arc that is centered about the actuator pivot axis; means for releasably securing the ramp-defining structure relative to the disk such that in a secured condition the cam portion overlies the outer circumference and in an unsecured condition the cam portion can be moved to a position clear of the disk while the lift-surface portion slides on the retention portion.