Safety monitoring device for monitoring safety-related states in a passenger conveyor system and method for operating same
US11618648B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 5, 2018 |
| Grant date | Apr 4, 2023 |
| Priority date | — |
| Expiry date | Dec 2, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2231/03
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A safety monitoring device monitoring safety-related states in a passenger conveyor system has first and second double contact relays each controlled by a control voltage to switch first and second normally open contacts and a feedback contact synchronously between an open and closed relay states. First and second controllers each determine properties of the system correlated with safety-related states and in dependence generate the control voltages. The controllers and two double contact relays form first and second safety monitoring switch arrangements for monitoring first and second safety-related states and correspondingly switch first and second switching states within a safety monitoring chain of the system. The first arrangement includes the first contact of the first connected in series with the first contact of the second relay. The second arrangement includes the second contact of the first relay connected in parallel with the second contact of the second relay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.