06006866 is referenced by 14 patents and cites 3 patents.

An elevator is provided with a car and inner and outer doors. The inner door registers with one of the outer doors when the car is disposed within a floor zone. A solenoid on the car has a plunger for blocking the inner door from opening. Power will only be applied to the solenoid to move the plunger to a retracted position to allow the inner door to be fully opened when both the car is disposed within a floor zone and the inner doors are being opened by the main elevator controls. A floor zone sensor is mounted to the car for detecting when the elevator is disposed within one of the floor zones. A door sensor is also mounted to the car for detecting when the inner door is being opened by the main elevator controls. A controller operates the electric solenoid to lift the plunger from the extended position to the retracted position in response to receiving both a door data signal from the door sensor and a floor zone data signal from the floor zone sensor. In the event of a power loss, the plunger will strike a lift clip so that the inner door may close.

Title
Elevator door restrictor
Application Number
512489
Publication Number
6006866
Application Date
June 17, 1998
Publication Date
December 28, 1999
Inventor
Tom J Harrison
Grapevine
TX, US
Gregory L Horne
Watauga
TX, US
Agent
Felsman Bradley Vaden Gunter & Dillon
Agent
James E Bradley
Assignee
Advanced Microcontrols
TX, US
IPC
B66B 13/14
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