Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5129486 | Elevator door lock | Christian G. Tonna | 1992-07-14 |
| 5105916 | Elevator door coupling device | John Chao Chang | 1992-04-21 |
| 4762217 | Escalator handrail guide | — | 1988-08-09 |
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5129486 | Elevator door lock | Christian G. Tonna | 1992-07-14 |
| 5105916 | Elevator door coupling device | John Chao Chang | 1992-04-21 |
| 4762217 | Escalator handrail guide | — | 1988-08-09 |