Patents by Inventor Per Olaf Pahr

Per Olaf Pahr has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5079649
    Abstract: An erase device for a magnetic layer memory having relative motion of a storage medium with respect to a combined magnetic head system includes a magnetic erase head having a single coil winding. Both ends of the winding of the erase head can be connected to a DC supply voltage via a respective inductor and, via a respective switch, to a potential that deviates from the DC voltage. The switches are alternately activated for identical time intervals by complementary control pulse sequences. The drive circuit for the erase head forms a DC-AC converter having symmetrical drive of the erase head.
    Type: Grant
    Filed: June 13, 1990
    Date of Patent: January 7, 1992
    Assignee: Tandberg Data AS
    Inventor: Per Olaf Pahr