PURPOSE: To surely detect a brake abnormality and compensate the shortage of braking torque with motor torque to carry out operation to the final end floor by detecting the shortage of braking torque caused by the abnormality of a brake device, together with the existence of a braking command by means of the rotation of a motor.
CONSTITUTION: A braking command is outputted from a sequence control means 25 to a brake control circuit 26 thereby restricting the rotation of a cage driving motor by the action of a brake coil 11, whereas, if the rotation of the motor is detected by a counter 27, this is detected as a brake abnormality by a brake abnormality detecting means 28. According to the abnormality detection signal thereof, a motor control means 22 controls the motor so as to generate braking torque by the motor itself instead of a brake device to make a cage travel to the final end floor, via a pulse width modulating circuit 23 and an inverter 24. Thus, by rapidly coping with the brake abnormality, the safe operation of an elevator can be performed.
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