Read/write arrangement for a magnetic terminal
AssigneeNorthern Telecom Limited
InventorsWilliam D. Westwood, Steven Kos, Herman W. Willemsen
Life of this patent
Estimating the term…
Abstract
A terminal has a reciprocating print head bearing a series of linearly arranged, individually-magnetizable styli for printing on magnetic particle oriented paper. The terminal may be used as a printer, or as a display by combining the printer with an erasing head comprising a series of linearly arranged magnets which create a rotating magnetic field to erase the magnetic particle oriented paper when the erasing head is reciprocated. The print and erase heads are mounted on a common carriage. The terminal is cheap to manufacture and, if used as a printer, has the advantage of reusable paper. If used as a display, it required no refresh.
Claims6
A terminal comprising:
- writing means for recording information on magnetic particle oriented paper;
- elongate erasing means for erasing information recorded on the paper;
- means for advancing a sheet of said magnetic particle oriented paper past the writing means and the erasing means;
- means for reciprocating said writing means in a direction perpendicular to the direction of advance of said sheet and parallel to the plane of the sheet at the writing means;
- and
- means for longitudinally reciprocating said erasing means in a direction perpendicular to the direction of advance of the sheet and parallel to the plane of the sheet at the erasing means;
- wherein said erasing means is spaced from the writing means and comprises a plurality of permanent magnets arranged to produce at a portion of the paper adjacent to the erasing means a magnetic field having a predominant component in a plane parallel to the paper, a flux pattern of the field being such that on reciprocation of said erasing means, said portion of paper is subjected to a rotating magnetic field substantially in the plane of the paper, the field being sufficiently intense to reorient magnetic particles contained within the paper so that north-south polar axes thereof are parallel to the plane of the paper.
Dependencies are inferred from the claim text.