Abstract: A method for forming a disc stack assembly suitable for use in a disc drive. A number of discs are loaded onto a spindle motor hub and a disc clamp assembly is installed to secure the discs to the hub. The disc clamp assembly includes an annular retaining ring and a substantially planar, disc shaped clamp plate. The annular retaining ring is secured within an annular ring recess of the spindle motor hub and deforms the clamp plate so that the clamp plate applies an axially directed clamping force to the discs. The disc clamp includes an annular hat flange. The disc stack assembly is preferably balanced by selectively removing material from the hat flange or by attaching a balance weight to the hat flange.

Abstract: A disc stack assembly for use in a disc drive. A spindle motor hub includes an annular ring recess. A disc is clamped to the spindle motor hub by a disc clamp assembly comprising a clamp plate and a retaining ring. The clamp plate includes an inner ring engagement portion, an outer disc engagement portion, and an initial, substantially planar shape in an undeformed state. The retaining ring is secured within the annular ring recess and maintains the clamp plate in a conically deformed state so that the inner ring engagement portion of the clamp plate applies a first moment force against the retaining ring while the outer disc engagement portion of the clamp plate applies a second moment force as an axially directed clamping force upon the disc.

Abstract: A method for forming a disc stack assembly suitable for use in a disc drive. A number of discs are loaded onto a spindle motor hub and a disc clamp assembly is installed to secure the discs to the hub. The disc clamp assembly includes an annular retaining ring and a substantially planar, disc shaped clamp plate. The annular retaining ring is secured within an annular ring recess of the spindle motor hub and deforms the clamp plate so that the clamp plate applies an axially directed clamping force to the discs. The disc clamp includes an annular hat flange. The disc stack assembly is preferably balanced by selectively removing material from the hat flange or by attaching a balance weight to the hat flange.

Abstract: A disc stack assembly for use in a disc drive. A spindle motor hub includes an annular ring recess. A disc is clamped to the spindle motor hub by a disc clamp assembly comprising a clamp plate and a retaining ring. The clamp plate includes an inner ring engagement portion, an outer disc engagement portion, and an initial, substantially planar shape in an undeformed state. The retaining ring is secured within the annular ring recess and maintains the clamp plate in a conically deformed state so that the inner ring engagement portion of the clamp plate applies a first moment force against the retaining ring while the outer disc engagement portion of the clamp plate applies a second moment force as an axially directed clamping force upon the disc.

Abstract: Embodiments of apparatus are directed to a rotational shock tester system comprising a disc drive support system, a drop mechanism and an impact apparatus. The disc drive support system includes a rotation plate, wherein a disc drive is coupled to the rotation plate. The drop mechanism is coupled to the disc drive support system and includes an elevating apparatus, wherein the elevating apparatus elevates and releases the rotation plate which is supporting the disc drive. The impact apparatus is releasably coupled to the drop mechanism and is aligned with the rotation plate such that upon release of the rotation plate, the rotation plate impacts the impact apparatus such that the impact apparatus imparts an angular acceleration to the rotation plate and imparts a rotational shock to the disc drive.