Issued Patents 1997
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5662426 | Drive hub and spindle assembly for cylindrical brooms | — | 1997-09-02 |
| 5630246 | Floor cleaning apparatus with flap having wear indicator | Christopher M. Knowlton, Robert J. O'Hara | 1997-05-20 |
| 5611108 | Floor cleaning apparatus with slidable flap | Christopher M. Knowlton, Robert J. O'Hara | 1997-03-18 |
| 5608947 | Floor cleaning apparatus with pre-filter | Christopher M. Knowlton, Robert J. O'Hara | 1997-03-11 |