Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4880082 | Method for determining the position of an elevator car and a pulse count based floor selector | Heimo Makinen, Jouko Perttula | 1989-11-14 |
| 4804067 | Inverter control apparatus for elevator motor | — | 1989-02-14 |
| 4799139 | Voltage regulation for three-phase inverters | Urpo Sten, Pekka Nummi, Pekka Hytti | 1989-01-17 |