Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6206145 | Brake apparatus for a hydraulic elevator | Edward G. Cable, Richard Alistair Balfour Stewart | 2001-03-27 |
| 5638937 | Handrail drive system conversion | Lawrence V. Birney, Thomas Keller, William I. Thompson, Richard Alistair Balfour Stewart | 1997-06-17 |
| 4491200 | Locking mechanism for an elevator car door | William I. Thompson, Mark F. Welter | 1985-01-01 |