Emergency stop apparatus for electric elevators

Claim 1

An emergency stop apparatus for electric elevators comprising: a D.C. motor for driving a cage with passengers; variable D.C. power source means powered by an A.C. power source and coupled to said motor for controllingly driving said motor; means for coupling the D.C. power source means to the motor; a power stoppage memorizing circuit for detecting a power stoppage of the A.C. power source and memorizing the power stoppage; first means for monitoring an elevator system safety function to verify a predetermined performance of said system function; second means coupled to said first means for stopping said motor when said first means senses a malfunction; first motor stopping means for stopping said motor to stop the cage when said power stoppage memorizing circuit detects a power stoppage; a memory erasing circuit for automatically erasing the memory of said memorizing circuit after the cage stops when A.C. power is restored and if no safety malfunction is sensed by said first means; and means for issuing a start command through operation from an advance floor button in the cage by the passengers themselves or a floor button after the operation of said memory erasing circuit to release said motor stopping means to permit the cage to restart its travel.