Patents by Inventor G. Randall Stevens

G. Randall Stevens 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: 4300174
    Abstract: The tunnel-erase-type guard band "writing" along the tracks of a disk in a disk file is controlled by the same microcomputer which controls transducer repositioning in the seek mode. The micro-computer meters different delays for onset and cessation of erasing in relation to a signal (write gate) accompanying the data to be recorded; and these delays are longer for tracks having smaller diameters. The leading and trailing edges of the write gate signal trigger interrupts for the microcomputer, the interrupt channel is released only after the particular delay has been metered.
    Type: Grant
    Filed: December 21, 1979
    Date of Patent: November 10, 1981
    Assignee: PerSci, Inc.
    Inventors: Jefferson H. Harman, G. Randall Stevens
  • Patent number: 4237502
    Abstract: A disk drive for one or more spinning disks has a voice coil motor, driving the transducer carriage and controlled by two feedback loops, respectively, for hold and seek modes and enabled by a microcomputer which is additionally inserted into the seek mode feedback loop. The microcomputer receives step pulses from a controller host as well as detent pulses through a path of that seek loop; the pulses serve as interrupts and the microcomputer selects digital speed signals on the basis of step and detect pulse counts. An a/d converter inserts that signal as command into the seek loop.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: December 2, 1980
    Assignee: Per Sci, Inc.
    Inventors: Robert W. Erickson, Jr., G. Randall Stevens