Detection of escalator safety circuit component operability
US5601178A · kind A · utility
Inventors
Key dates
| Filing date | Mar 16, 1995 |
| Grant date | Feb 11, 1997 |
| Priority date | — |
| Expiry date | Mar 16, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B25/00
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A start up check relay is energized whenever escalator motor motive power is interrupted. The start up check relay checks speed and non-speed-dependent safety circuit components to determine whether these safety circuit components have all come to an escalator start up state. When the start up condition of these safety circuit components has been verified the circuit allows power to be applied to the escalator motor. When power is applied to the escalator motor, a start up delay timer is energized and the start up check relay is de-energized. When speed-dependent components of the escalator have come to operating speeds, the start up delay timer will be de-energized, and the escalator will continue movement in its normal operating mode provided that all safety circuits are fully operational.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.