Patents by Inventor Vishnu Srivastava

Vishnu Srivastava 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).

  • MRI magnet with fast ramp up capability for interventional imaging
    Patent number: 6097187
    Abstract: Primary superconducting coils (50) generate a magnetic field through an examination region (10). Stabilizing coils (70) are magnetically coupled with the magnetic field generated by the primary coils. A primary persistence switch (60) and a stabilizing coils persistence switch (72) are opened when the primary coils are connected to a current source (62) to ramp-up the magnetic field. The persistence switches are closed, disconnecting the primary coils from the current source and connecting the primary coils and the stabilizing coils into closed loops. As the magnetic flux generated by the primary coils fluctuates as the primary coils stabilize, the changing flux induces currents in the stabilizing coils. The currents induced in the stabilizing coils generate an offsetting magnetic flux such that the net magnetic flux generated by the primary and stabilizing coils is held constant.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: August 1, 2000
    Assignee: Picker International, Inc.
    Inventors: Vishnu Srivastava, Gordon D. DeMeester, Michael A. Morich