Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4716840 | Drafting board with replaceable surface layer | David C. Pflieger | 1988-01-05 |
| 4269615 | Filter assembly | Jon A. Zboralski, Harry N. Grow | 1981-05-26 |
| 4197837 | Inflatable-deflatable pad and air control system therefor | William D. Christoffel, Paul R. Zeman | 1980-04-15 |