PURPOSE: To attain safe and simplified operations by a method in which when an arm is raised by an ascending operation switch, a shovel is made into a loading attitude, while is made into a dumping attitude when a dump switch is set on, but into a shoveling attitude when dump switch is set off.

CONSTITUTION: An ascending operation switch 3 to make the angle of a shovel 6 a loading attitude A at the same time a load arm 2 goes up and a dump switch 7 to make the shovel 6 a dumping attitude C by on-operation but to make it a shoveling attitude B by off-operation are provided. When a dump switch 7 is set ON by a dump switch trigger 10, the shovel 6 is controlled from the attitude A to the attitude C. When the switch 7 is set OFF, the shovel 6 is controlled to return it to the attitude B set up by a shovel angle setter 17. When ON-OFF operation of the trigger 10 is repeated, the shovel 6 can quickly discharge the load by repeating the attitudes C and B.