Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6060847 | Interactive amusement ride | Philip Hettema, Craig Robert Hanna, Nicholas H. Drobnis | 2000-05-09 |
| 4347414 | Arc shorting device | Peter Headley, Thomas E. Kelsey | 1982-08-31 |