PURPOSE: To prevent various inconvenience depending on a self-propelling condi tion of a door by applying a necessary electric energy from a battery power source to a control/driving member when it is detected that a feeding voltage is less than a standard value.
CONSTITUTION: When a power source cutting detector 32 detects that the feeding voltage is less than a specific standard value by a cutting of power source from a normal power feeding condition, the output signal responding to the detection of the abnormal condition is added to the speed instruction generator 22 in a microcomputer 31. And, corresponding to that, the speed of the door of an elevator is reduced depending on a speed instruction output from the speed instruction generator 22. In this case, the power feeding to an inverter control circuit 17 is made by passing through a DC-DC converter 33. As a result, various inconveniences depending on the self-propelling condition generated by the inertia of the door itself of the elevator, when an abnormal condition is generated in the power source, can be prevented securely.
HIRABAYASHI TERUMI
TAWADA MASANORI
KODERA TOSHIYUKI