Patents by Inventor Donald Christopher Leonard

Donald Christopher Leonard 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).

  • Simultaneous surge test of two coils of an assembly of series connected coils
    Patent number: 5694044
    Abstract: A circuit detects insulation defects in a coil assembly including a plurality of series connected coils. A first voltage pulse is applied to a first coil of the coil assembly, a second voltage pulse is applied to a second coil of the coil assembly, the first and second coils being substantially diametrically opposite to one another, and the first and second voltage pulses being substantially equal to one another and oppositely poled relative to the coil assembly. A first voltage waveform across the first coil is monitored, and a second voltage waveform across the second coil is monitored. A first signal is derived from the first voltage waveform, a second signal is derived from the second voltage waveform, and a differential percentage value based on the first signal and the second signal is computed. An insulation defect is then determined based upon the differential percentage value.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: December 2, 1997
    Assignee: Fisher Data Products, Inc.
    Inventors: John Llewellyn Crowley, John David Painter, James Timothy Dillon, David Allan Boyer, James Allen Fisher, James Hubert Walters, Donald Christopher Leonard