The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 19, 2022
Filed:
Jul. 03, 2017
Inventio Ag, Hergiswil, CH;
Urs Lindegger, Ebikon, CH;
INVENTIO AG, Hergiswil NW, CH;
Abstract
An elevator has a drive unit displacing an elevator car in an elevator hoistway, an elevator controller controlling operation of the drive unit, multiple safety switches switchable upon occurrence of safety relevant events, and a safety chain overlay control unit including a safety PLC. The PLC has first connectors connected to first safety switch contacts and second connectors connected to second safety switch contacts. The PLC monitors a current safety status of the elevator and identifies a safety critical status by detecting when at least one of the safety switches changes its switching state and comparing the current switching states of the first and second safety switches. The PLC interrupts a main energy supply to the drive unit in response to the safety critical status of the elevator. Comparing switching states of the safety switches connected to the first and second connectors also enables detecting faulty safety switches.