05655627 is referenced by 15 patents and cites 10 patents.

An elevator is provided with a car, an inner door mounted to the car and outer doors mounted to floor openings which define floor zones. The inner door registers with the outer doors when the car is disposed within one of the floor zones. The elevator includes a door restrictor having an electric solenoid mounted to the car so that the inner door cannot be opened more than four inches when the elevator is between floor zones. The electric solenoid has a plunger which is normally in an extended position to block the inner door from opening. Power will only be applied to the electric solenoid to lift the plunger from the extended position 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 initiated to move slightly 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.

Title
Elevator door restrictor
Application Number
8/512489
Publication Number
5655627
Application Date
August 8, 1995
Publication Date
August 12, 1997
Inventor
Tom J Harrison
Grapevine
TX, US
Gregory L Horne
Watauga
TX, US
Agent
James E Bradley
Assignee
Advanced Microcontrols
TX, US
IPC
B66B 13/06
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