Method and apparatus for sensing fault conditions for an elevator active roller guide
US5824976A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 1997 |
| Grant date | Oct 20, 1998 |
| Priority date | — |
| Expiry date | Mar 3, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B7/044
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A fault sensor to be used with a controller as part of an active roller guide (ARG), the fault sensor disabling the ARG if it determines that any pair of current-force magnitudes for any of the ARG actuators is outside of a predetermined acceptable operating envelope, indicating an anomalous, or fault, condition. The ARG fault sensor receives, periodically, magnitudes of current and flux density for each actuator. From these, it calculates an actuator force and then checks that the current-force pair for each actuator is within the operating envelope. This envelope is curvilinear in its boundary. To check the curved segments of the envelope boundary, the fault sensor calculates the gap for each actuator. If each gap magnitude is within range, all that is left is to check the straight segments of the envelope boundary. This is done by simply checking that each actuator current and force magnitude is less than a predetermined limit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.