Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11945690 | Elevator compensation assembly monitor | Randy Roberts | 2024-04-02 |
| 11649138 | Elevator system monitoring and control based on hoistway wind speed | Daniel Pahng | 2023-05-16 |
| 11524872 | Elevator compensation assembly monitor | Randy Roberts | 2022-12-13 |
| 11034546 | Elevator governor | Randall S. Dube | 2021-06-15 |
| 10450162 | Electromagnetic brake control circuitry for elevator application | Amir Lotfi, Steven M. Millett | 2019-10-22 |
| 10399820 | Elevator tension member stiffness estimation and monitoring | Randall Keith Roberts, David Wayne Mckee, Richard L. Hollowell | 2019-09-03 |
| 10011463 | Elevator door friction belt drive including one or more markers | John Ferrisi | 2018-07-03 |
| 9975735 | Cab isolation of an elevator car | Randall Keith Roberts, Richard N. Fargo, Walter Thomas Schmidt | 2018-05-22 |
| 9033111 | Elevator governor system | — | 2015-05-19 |
| 8459415 | Elevator motion profile control including non-instantaneous transition between jerk values | Daryl J. Marvin, Steven D. Coste, Randall Keith Roberts | 2013-06-11 |