Radially loaded disc mounting system for a disc drive

DETAILED DESCRIPTION The present invention is a disc mounting system for mounting the discs of a disc drive in a fixed radial relationship to the hub of a spindle motor.
The disc mounting system includes a disc mounting ring associated with each disc in the disc stack.
The disc mounting ring includes at least one axially extending finger against which a portion of the inner diameter of the disc is brought to bear in an interference fit.
In a first embodiment of the invention, the disc mounting ring includes a single finger and that portion of the inner diameter of the disc radially opposite the finger directly contacts the spindle motor hub.
In other embodiments of the invention, the disc mounting ring includes a plurality of fingers spaced circumferentially about the ring and the inner diameter of the disc bears on all fingers and has no direct contact with the spindle motor hub.
In all embodiments, it is envisioned that sufficient axial force will be applied to the discs at the time of manufacture to produce some cold-flowing of the disc mounting ring material of the fingers.
Mechanisms for controlling the axial location of the discs relative to the spindle motor hub are also disclosed.
It is an object of the present invention to provide a system for mounting the discs in a disc stack to the hub of a spindle motor used to rotate the discs in a disc drive.
It is another object of the invention to provide a disc mounting system which prevents shifting of the discs relative to the hub of the spindle motor due to differential thermal expansion.
It is another object of the invention to provide a disc mounting system which prevents shifting of the discs relative to the hub of the spindle motor due to the applications of large mechanical shocks.
It is another object of the invention to provide a disc mounting system that is suitable for use in a high volume manufacturing operation.
It is another object of the invention to provide a disc mounting system that can be implemented in a high volume manufacturing operation in an economical manner