Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6052863 | Central vacuum cleaner muffler | J. Adin Mann, III, David K. Holger, Douglas E. Johnson | 2000-04-25 |
| 6016346 | Low-profile speakerphone with downward oriented microphone configuration | Frank Annerino, Mark Randall Dreher, Scott A. Chastain | 2000-01-18 |
| 5737797 | Central vacuum with acoustical damping | Douglas E. Johnson, Steven D. Lauritsen, J. Adin Mann, III, David K. Holger | 1998-04-14 |