Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4884673 | Curved escalator with fixed center constant radius path of travel | — | 1989-12-05 |
| 4883160 | Curved escalator with fixed center constant radius path of travel | Frank Sansevero, Klaus Seehausen, Dat Nguyen, Peter Borchers | 1989-11-28 |