Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7802859 | Refilling a used ink cartridge | David Tyvoll, Winthrop D. Childers, David M. Hagen | 2010-09-28 |
| 4265057 | Collet chuck aligning assembly for gem faceting machines | — | 1981-05-05 |