PURPOSE: To enable accessories to be easily attached or removed by providing the tip of an arm, with engaging pins to be exposed or concealed in the left and right directions, and by providing the tips of hydraulic cylinders arranged on the back side of the arm, with click bodies for suspending the accessories.

CONSTITUTION: Hydraulic cylinders 4, 6 are operated, and a boom 3 and an arm 5 are vertically oscillated, and a hook 11 is brought close by the engaging pin 19 of a bucket 17, and the pin 19 is hooked to the hook 11. When the arm 5 is slightly moved up or down and the bucket 17 is suspended and a bucket cylinder 7 is shortened, the tip of the arm 5 is inserted in a space between the fitting bodies 18 of the bucket 17. After that, when the engaging pins 15, 16 of the arm 5 coincide with the pin holes 20, 21 of the bucket 17, the hydraulic cyliners are worked, and via a working plate, the pins 15, 16 are allowed to respectively project to an external side from the side surface of the arm 5. Besides, the pins 15, 16 are inserted into the holes 20, 21, and the bucket 17 is freely, rotatably connected to the arm 5.