Apparatus and method for degaussing magnetic storage media
AssigneeDowty RFL Industries, Inc.
InventorAlbert Helfrick
Life of this patent
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Abstract
An apparatus and method for degaussing a magnetic storage medium, such as a reel of magnetic tape, is disclosed. A pair of opposing E-laminations have windings on their respective center legs. A reel of magnetic tape is inserted in the region between the E-laminations, and is rotated. An AC potential is coupled in series across the windings, to obtain a first magnetic field orientation in the region between the E-laminations. The direction of connection of one of the windings of the series arrangement is then reversed, to electrically alter the magnetic field orientation. This provides an effective degaussing of the magnetic tape.
Claims20
A method for degaussing a magnetic storage medium, comprising the steps of:
- disposing the magnetic storage medium in the region between a pair of substantially parallel windings;
- energizing the windings a first time to obtain either one state wherein the fields through the centers of the windings are in the same direction or another state wherein the fields through the centers of the windings are in opposing directions;
- energizing the windings a second time to obtain the state not used during said first energizing time;
- and
- rotating the magnetic storage medium during said first and second energizing of the windings.
Apparatus for degaussing magnetic storage media, comprising:
- a pair of spaced apart magnetic field generating means;
- means for inserting a magnetic storage medium into the region between said field generating means;
- means for rotating the magnetic storage medium;
- and
- means for energizing both of said field generating means to produce a magnetic field substantially along one direction through the magnetic storage medium and for subsequently energizing both of said field generating means to electrically shift the direction of the produced magnetic field to be substantially along another direction through the magnetic storage medium, said another direction being perpendicular to said one direction;
- and.
Apparatus for degaussing a reel of magnetic tape, comprising:
- a pair of opposing E-laminations, each having a coil wound on the center leg thereof;
- means for inserting the reel of magnetic tape into the region between said E-laminations;
- means for rotating the reel of magnetic tape;
- means for coupling an AC potential in series across said windings;
- means for reversing the direction of connection of one of said windings in the series arrangement;
- a capacitor coupled across said windings;
- and
- means for controlling said reversing means to be operative during a portion of an operating cycle of the degaussing apparatus.
Dependencies are inferred from the claim text.