An apparatus for controlling a movable object, and an elevator system having such an apparatus

摘要

To obtain accurate data on the position of an elevator cage (1), in spite of power failure or vertical vibration of the cage, a serial absolute rotary encoder (SAE) (10) is rotated in accordance with the movement of the elevator cage (1). An output of the SAE (10) when the cage (1) is positioned at a reference floor is stored. When data on the position of the cage is necessary, the current output of the SAE (10) is read and the difference between the read output and the stored reference positional data is calculated. An uninterruptible power source having a capacity low enough only to back up a C-RAM suffices. The speed of the cage (1) is calculated from the output of a pulse encoder (11) and compared with a desired speed calculated from the calculated position data to control the torque of a driving motor (5).