Rigid magnetic disc memory apparatus including open loop stepper-motor-driven read/write head
US4194226A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1978 |
| Grant date | Mar 18, 1980 |
| Priority date | — |
| Expiry date | Apr 24, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5521
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A rigid magnetic disc memory apparatus for use with a data processing system. A magnetic read/write head is accurately positioned parallel and adjacent to the plane of a rigid magnetic disc with high track density by a stepper motor in an open-loop fashion without servomechanism control. The memory apparatus includes: band structure including a spring bias for coupling stepper motor drive to apparatus supporting magnetic heads above and/or below the spinning disc and for temperature compensating for disc/apparatus expansion and contraction; manually operable control for zeroing the magnetic heads, moving and locking them in the disc's landing zone as, for example, while in transit, and providing a travel limit to head movement when the memory apparatus is operating; keying apparatus for preventing erroneous insertion and mis-alignment of and damage to an optical transducer relative to an optical mask arranged to spin with the disc structure; shim apparatus for precisely positioning the magnetic heads in the spin axis direction; viscously-coupled inertia apparatus for damping the stepping motor's step-rotary motion; a device for employing spinning motion associated with the disc for…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.