Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D306565 | Door mounted advertising display chime | Margaret A. Erdall | 1990-03-13 |
| 4833454 | Door chime | Margaret A. Erdell | 1989-05-23 |
| D300642 | Display sign | Margaret A. Erdell | 1989-04-11 |