PURPOSE: To automate the dumping operation of loads by a method wherein a specified number of holes are formed in the bottom of a case, a chute is laid on the bottom thereof and the push rods of a push-up mechanism supported on a case supporting device are passed through the holes of the case bottom to force up the chute.

CONSTITUTION: Three or more holes 2 are formed in the bottom of a case 1, a chute 3 is laid within the case 1 and loads W are placed on the chute 3. This case 1 is supported on a supporting plate 14. On the other hand, a push-up rod base plate 12 having push rods 13 is provided below the supporting plate 14 and is made freely vertically movable by an air cylinder 10. The push rods 13 are made up of the combination of a long rod 13b and a short rod 13a. The push rods 13 are moved upwards by the air cylinder 10 and passed through the holes 15 of the supporting plate 14 and then through the holes 2 in the bottom of the case 1 into the case 1 to push up the chute. Due to the difference in length between the push rods 13, the chute 3 is tilted on the case 1 and the loads W are slid down the chute and dumped automatically.