This invention provides a disk memory that seats a memory disk with a consistent high accuracy by a drive chuck that engages only one side of the disk. Features of the invention reside in the driven hub of the disk and in the drive chuck.
The invention also provides a unique attachment of the storage medium of the disk to the disk hub. The attachment eases the elastic deflection of the disk, as conventionally occurs upon read-write engagement with the transducer head.
Conventional disk drives, particularly for flexible magnetic media often termed "floppy disks", engage the center of the disk from opposite sides to position the disk and to rotate it. Consistent accurate positioning of each disk is required to attain proper read/write interaction with the transducer head and to attain correct track location and density.
Floppy disks traditionally are relatively large, with a diameter of either five inches or eight inches. There is now a need for equally high performance disk memories with significantly smaller disks, particularly with a diameter under four inches. Conventional practices for mounting, locating and driving the magnetic medium of a floppy disk are not readily applied to such smaller disk memories.
It accordingly is an object of this invention to provide disk memory apparatus that locates a memory disk with consistent high accuracy by engaging only one side of a memory disk.
A further object of the invention is to provide apparatus which attains such location of a disk in both the radial, i.e. lateral, and the vertical directions.
Another object of the invention is to provide disk-locating memory apparatus of the above character which attains repeatable indexing of different disks, as desired to use the full track capacity of the recording medium.
It is also an object of the invention to provide disk memory apparatus of the above character which is highly reliable and low in cost, and further which is well suited for use with memory disks of small size.
It is a further object of this invention to provide a magnetic memory disk in which the recording medium is relatively free to deflect from the disk hub, as desired for transducer head penetration at recording tracks close to the disk center.
Other objects of the invention will in part be obvious and will in part appear hereinafter.