Issued Patents 2021
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11124389 | Elevator car door interlock | Richard E. Kulak | 2021-09-21 |
| 11072515 | Automated elevator maintenance mode initiation | Tadeusz Pawel Witczak | 2021-07-27 |
| 11046557 | Elevator door interlock assembly | Richard E. Kulak | 2021-06-29 |
| 11040858 | Elevator door interlock assembly | Richard E. Kulak | 2021-06-22 |
| 11034548 | Elevator door interlock assembly | Richard E. Kulak | 2021-06-15 |
| 10882720 | Elevator car door interlock | Richard E. Kulak | 2021-01-05 |