PURPOSE: To allow shutting a door certainly and safely even in case a wind pressure acts on the elevator door or clog is generated with dust.
CONSTITUTION: A wind speed meter 7 is furnished in an elevator car. A motor 5 to open and shut the door is controlled upon the deviation Vp-Vt of the speed voltage from the speed command voltage Vp. The upper limit value Vd of the deviation Vp-Vt is determined by the resistance 3c of a torque limiting circuit 3. When any failure in the wind speed is sensed by a wind speed failure sensing circuit 8, a transistor 9a is turned on so that resistance 9b becomes parallel with the resistance 3c, and the upper limit value Vd rises. and the torque or speed of the motor 5 increases to actuate the shutting motion of the door.
TAWADA MASANORI
TAKAHASHI TATSUJI
Next Patent: ELEVATOR DOOR CONTROL DEVICE