To always provide the best engine magical distribution, by providing means by which an unloading valve is selectively operated to be opened and closed according to work conditions.
Detected signals read from a boom angle sensor 21 and a bucket position sensor 22, are discriminated in a condition that a mounted article is filling. Also, if such conditions are discriminated that an accelerating pedal is operated at a predetermined set value or more when considering on the basis of a detected signal read from the detecting sensor 24 of an accelerating pedal manipulated variable, and a brake pedal is not operated when considering on the basis of a detected signal read from a detecting sensor 25 for detecting the presence of the operation of the brake pedal, the present work condition is judged that it is a work condition requiring tractive force preferentially than the driving force of a work apparatus, namely, a condition that a loader is filling a mounted article.
JIYON UOO RII
HO JIN KAN
