US 9,809,418 B2
Advanced smooth rescue operation
Prasanna Nagarajan, Farmington, CT (US); Amir Lotfi, South Windsor, CT (US); and Edward Piedra, Chicopee, MA (US)
Assigned to OTIS ELEVATOR COMPANY, Farmington, CT (US)
Filed by Otis Elevator Company, Farmington, CT (US)
Filed on Feb. 29, 2016, as Appl. No. 15/56,158.
Prior Publication US 2017/0247222 A1, Aug. 31, 2017
Int. Cl. B66B 5/06 (2006.01); B66B 1/32 (2006.01); B66B 13/14 (2006.01); B66B 1/28 (2006.01)
CPC B66B 1/28 (2013.01) [B66B 2201/34 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A method of operating an elevator system, the method comprising:
detecting, using a controller, when an external power source is unavailable;
controlling, using the controller, a plurality of components of the elevator system, wherein controlling comprises operating at least one of an elevator car, a drive unit, an inverter and a brake;
detecting, using the controller, an original direction of travel of the elevator car;
detecting, using the controller, a mode of the elevator car, wherein the mode includes at least one of a motoring mode, a near balance mode, and a regenerative mode;
determining, using the controller, a target floor; and
adjusting, using the controller, a velocity of the elevator car to reach the target floor in response to the mode detected; allowing, using the controller, the velocity of the elevator car to decrease to about zero velocity, when the near balance mode is detected; maintaining, using the controller, the about zero velocity for a selected duration of time; increasing, using the controller, the velocity of the elevator car in the original direction of travel until it reaches an automatic rescue operation velocity; maintaining, using the controller, the automatic rescue operation velocity for a second selected duration of time; and decreasing, using the controller, the velocity of the elevator car as the elevator car approaches the target floor;
wherein secondary power is provided to the brake, elevator doors, and a positional reference system in the controller;
wherein secondary power is not provided to a drive unit to propel the elevator.