Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4865137 | Drilling apparatus and cutter | John E. Campbell | 1989-09-12 |
| 4804026 | Self-supporting funnel | — | 1989-02-14 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4865137 | Drilling apparatus and cutter | John E. Campbell | 1989-09-12 |
| 4804026 | Self-supporting funnel | — | 1989-02-14 |