Patents by Inventor Alejandro D. Rojas

Alejandro D. Rojas 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).

  • Variable load motor drive control
    Patent number: 4963810
    Abstract: The invention relates to a method and apparatus for making low inertia motors useful under circumstances where the load exerting drag on the motor during start-up acceleration may be different from time to time. A ramped drive current as opposed to a conventional constant current limit signal is applied to the motor. The invention is particularly useful, for example, in magnetic tape drives which must adapt to variations in drag between one tape cassette or cartridge and another.
    Type: Grant
    Filed: October 27, 1989
    Date of Patent: October 16, 1990
    Assignee: Archive Corporation
    Inventors: Alejandro D. Rojas, John J. Ouintus