Method and apparatus for transferring magnetic signal from a master sheet to copy sheets
US4047230A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1976 |
| Grant date | Sep 6, 1977 |
| Priority date | — |
| Expiry date | Nov 26, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/865
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A master sheet is coated with a magnetic layer carrying magnetic signals in, for example, a spiral magnetic recording track, and is pressed into contact with a copy sheet which is also coated with a magnetic layer. A magnetic field is applied to the sheets to transfer the magnetic signals from the master sheet to the copy sheet. The copy sheet is then separated from the master sheet by air pressure, suction or mechanical means in a direction perpendicular to the sheets and subsequently fed away from the master sheet in a direction parallel to the sheets while maintained separated from the master sheet to reduce the transfer noise level to a negligible amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.