Safety circuit for lift doors
US7500650B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2004 |
| Grant date | Mar 10, 2009 |
| Priority date | — |
| Expiry date | Oct 18, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B13/22
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
An improved lift system door control or safety circuit utilizes locking devices for the lift shaft doors and lock sensors to monitor the status of the locking devices. The lock sensors are coupled to a lift drive unit control through a data bus, which need not be especially designed as a safety data bus. The lock sensors are repeatedly interrogated at short term intervals. The status of the doors is interrogated on a longer time interval, and such data is also passed to the drive unit control by the data bus. The interrogations are used to determine the operating condition of the locking sensors as well as whether communications or transmission errors are present.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.