Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5831409 | Electric vehicle propulsion system employing AC induction motor control | Frank A. Lindberg, David L. Schantz, Jr., Brian H. Smith, Charles S. Kerfoot, Joseph J. Springer +17 more | 1998-11-03 |
| 5634262 | Method of manufacturing heat dissipating transformer coil | Charles S. Kerfoot, Joseph J. Springer | 1997-06-03 |
| 5581171 | Electric vehicle battery charger | Charles S. Kerfoot, David L. Schantz, Jr. | 1996-12-03 |
| 5469124 | Heat dissipating transformer coil | Charles S. Kerfoot, Joseph J. Springer | 1995-11-21 |