Spindle lock shaft for disk drive media

Claim 1

In a disk drive apparatus having a disk pack with a motor driven spindle for rotating the disk pack, said disk pack including a mounting plate located at the bottom thereof and bearing upon the top of said motor driven spindle, said motor driven spindle comprising: a spindle housing having a hollow interior chamber with an inwardly extending flanged portion at the top thereof; a shaft disposed within the hollow interior chamber of said spindle housing and secured to the mounting plate, said shaft having a top portion, a bottom portion and a mid portion, the mid portion having a diameter smaller than the top portion and the bottom portion; and means for spring loading said shaft within the hollow interior chamber of said spindle housing, said spring-loading means comprising: a first spring extending along the length of only the mid portion of said shaft, said first spring being compressibly loaded against the inwardly extending flanged portion at the top of the hollow interior chamber of said spindle housing so as to bias said shaft downwardly, a second spring extending over only the bottom portion of said shaft, said second spring compressibly loaded against the bottom of the hollow interior of said spindle housing so as to bias said shaft upwardly, and means, located at the bottom of said first spring and the top of said second spring, for compressible loading said first and second springs within the hollow interior chamber of said spindle housing.