Helical scan tape record apparatus and method
CA 2005672 A1 · Owner: Minnesota Mining And Manufacturing Company · Inventors: Wirth, Wayne M.; Vogelgesang, Peter J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus for transferring information to or from a magnetic tape has the tape wound and advanced along a helical path on the outer cylindrical surface of a rotatable drum. Tape is supplied to the helical path on the drum from within the drum, and the drum has an annular groove on its outer surface which extends along the helical path and is perpendicular to the axis of the rotation of the drum. A system for reading and/or writing information on the tape is positioned entirely on the outside of the drum and is stationary relative to the rotation of the drum and movement of the tape thereon. The system includes at least one magnetic head which is in contact with the magnetic tape opposite …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 15, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 15, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 15, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.