Patent attributes
When a long-period-earthquake occurs, an elevator is controlled to ensure that an abnormality is positively judged and that the elevator can be safely and promptly returned to a normal operation. For this purpose, by providing a usual seismic sensor and a long-period seismic sensor that detects long-period components of the shakes of a building, which are not detected by the usual seismic sensor, at two stages, an earthquake emergency return operation is performed when the seismic sensor has gone into action and when a first level has been detected by the long-period seismic sensor, a long-period-earthquake emergency return operation, which involves giving a notice to outside the elevator and inside a car, is performed. When a second level has been detected by the long-period seismic sensor, a notice is given to outside the elevator and inside a car, and a door opening action is performed by stopping the car at the nearest floor and a long-period-earthquake emergency return operation, which involves causing the car to travel to a temporary-stop floor, is performed, whereby the car is caused to suspend the operation. When no abnormality is discovered by performing an automatic inspection operation under prescribed conditions, the elevator is returned to a normal operation.
