Method and means for erasing recordings on magnetic paper, particularly for distance measuring equipment

Abstract

A magnetic recording medium is erased by mounting at least one magnet with its north-south poles parallel to the surface of the recording medium and transporting the recording medium in a plane horizontal to the north-south pole axis such that the magnetic field lines traverse the recording medium. The magnet may be mounted on an endless belt which moves substantially transverse to the direction of movement of the recording medium. The belt may be oscillated or moved continuously along its transverse path. In an alternative embodiment, magnets may be mounted on the end of an arm which is adapted to be rotated in parallel spaced relation to the surface of the recording medium. Also, a number of permanent magnets may be mounted in two rows in spaced relation to form an aperture therebetween for transport of the recording medium therethrough. The erasing means may be incorporated in apparatus for recording on the magnetic recording medium in which the endless belt supporting the magnet includes apertures therein which enable contact elements associated with the magnet to contact a pair of conductors for energizing the magnet either with AC or DC current.

Dependencies are inferred from the claim text.