06467585 is referenced by 30 patents and cites 3 patents.

A wireless safety chain for an elevator system includes a base transceiver connected to a system controller. A plurality of safety chain components each includes a physical sensor such as a switch, and a wireless transceiver. The physical sensor monitors the component status. The wireless transceiver communicates among the other safety chain components and the system controller. The wireless safety chain preferably employs a token scheme, where a token is sent from the base transceiver to one component, which in turn sends the token to another component, and so on, until the token returns to the base transceiver. Failure of the token to return to the base transceiver in a predetermined amount of time signals that the elevator system is unsafe.

Title
Wireless safety chain for elevator system
Application Number
9/899400
Publication Number
6467585 (B1)
Application Date
July 5, 2001
Publication Date
October 22, 2002
Inventor
Alberto Vecchiotti
Middletown
CT, US
Robert G Morgan
Bolton
CT, US
Michael Gozzo
Groton
CT, US
Agent
Wall Marjama & Bilinski
US
Assignee
Otis Elevator Company
CT, US
IPC
B66B 5/02
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