| 摘要 |
PROBLEM TO BE SOLVED: To enhance the comfortableness of a hydraulic elevator while occurrence of uncontrollability is avoided using a feedback control even in case any failure is generated. SOLUTION: Detecting devices 13, 17, 20 detect various conditions of a hydraulic elevator and emits appropriate feedback signal, and a main speed control device 16 calculates a speed controlling command value on the basis of the given feedback signal, and imaginary signal generating devices 14, 18, 21 generate signals approx. the same as the feedback signal of the detecting device at normal times. When the corresponding detecting device has emitted a feedback signal of abnormal value, signal selecting devices 15, 19, 22 give in lieu of the feedback signal the imaginary signal which the corresponding imaginary signal generating device has generated, to the main speed control device 16. |
