PURPOSE: To high increase a speed of a riding car and to perform installation in a multistory building by providing a speed control device of outputting a control command value to an electric motor in a manner wherein a deviation between a detection signal of a hydraulic cylinder pressure sensor and an oil pressure of a hydraulic tank is within a prescribed range.
CONSTITUTION: When a riding car 1 is lifted to rise, a speed control device 12 controls a rotational speed of an electric motor 10 so that a deviation between a detection signal of a hydraulic cylinder pressure sensor 7a and an oil pressure of a hydraulic tank 13 is provided within a prescribed range. When this deviation is provided within the prescribed range, pressure oil is supplied to a hydraulic cylinder from the hydraulic tank 13. Here, the speed control device 12 outputs a control command value to the electric motor 10 so as to lift the riding car 1 by a prescribed speed pattern. On the other hand, when the riding car 1 is lowered down, the speed control device 12 supplies pressure oil of the hydraulic cylinder to the hydraulic tank 13, to accumulate potential energy of the riding can 1 in the hydraulic tank 13. For instance, the energy is accumulated as potential energy of a fixed weight 13c.
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