US 12,258,241 B2
Elevator including safety monitoring that prevents excessive deceleration during slowdown failure
Riku Lampinen, Helsinki (FI); and Juha-Matti Aitamurto, Helsinki (FI)
Assigned to Kone Corporation, Helsinki (FI)
Filed by Kone Corporation, Helsinki (FI)
Filed on Jul. 1, 2019, as Appl. No. 16/458,971.
Claims priority of application No. 18185012 (EP), filed on Jul. 23, 2018.
Prior Publication US 2020/0024105 A1, Jan. 23, 2020
Int. Cl. B66B 1/28 (2006.01); B66B 5/00 (2006.01); B66B 5/06 (2006.01)
CPC B66B 5/0031 (2013.01) [B66B 1/28 (2013.01); B66B 5/06 (2013.01)] 19 Claims
OG exemplary drawing
 
17. An elevator comprising:
an elevator car vertically movable in an elevator shaft, the elevator shaft including top and bottom end terminals;
an electromechanical braking apparatus configured to brake movement of the elevator car; and
a safety monitoring unit configured to
determine a position of the elevator car based on measured position data of the elevator car and car speed of the elevator car based on measured speed data of the elevator car,
calculate from the measured speed data, with a maximum acceleration, a speed prediction for the car speed after a reaction time of the electromechanical braking apparatus,
calculate from the measured position data, with the maximum acceleration, a closest possible position of an approaching elevator car to the top end terminal or the bottom end terminal after the reaction time of the electromechanical braking apparatus,
calculate a maximum initial speed for the elevator car to decelerate from the closest possible position to a terminal speed of the top end terminal or the bottom end terminal, and
cause braking of the elevator car with the electromechanical braking apparatus in response to the speed prediction meeting or exceeding the maximum initial speed.