Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6052863 | Central vacuum cleaner muffler | Stephen P. Rittmueller, J. Adin Mann, III, Douglas E. Johnson | 2000-04-25 |
| 5737797 | Central vacuum with acoustical damping | Stephen P. Rittmueller, Douglas E. Johnson, Steven D. Lauritsen, J. Adin Mann, III | 1998-04-14 |
| 4655086 | Method and means for measuring sound intensity | Anna Mielnicka-Pate | 1987-04-07 |