POWER SOURCE DEVICE FOR WORKING MACHINE

摘要

Power distribution of an engine and a power storage device is determined according to the amount of stored power in an electric power storage device, and the amount of stored power in the electric power storage device is maintained in an adequate range. A power source device for working machines is provided in which a hydraulic pump (3) and a generator-motor (4) are connected parallel to an engine (1) serving as a common power source, a battery (7) serving as an electric power storage device is charged by means of the generator function of the generator-motor (4), and the generator-motor (4) is driven by means of the discharge power of the battery (7) to perform the motor function. Using a controller (8), the power distribution of the engine (1) and the generator-motor (4) are determined according to the actuator-required power, the charging power and discharging power of the battery which are set according to the amount of stored power in the battery in such a way that the amount of stored power in the battery is maintained in a predetermined range, and the preset engine power.