An opening portion that is formed so as to pass-through an opening/closing plate portion of a gate, can be disposed at a region overlapping a lower end opening of a hopper. The opening portion is structured by a first pass-through portion, and a second pass-through portion that is formed so as to be continuous with the first pass-through portion. A width, in a direction orthogonal to a lined-up direction in which the first pass-through portion and the second pass-through portion are lined up, is narrower than the first pass-through portion. Further, a driving mechanism moves the gate such that the opening/closing plate portion moves in the lined-up direction as seen in a plan view. Based on a preset target value of weight of sand, a control section controls the driving mechanism so as to decrease an amount of overlap of the opening portion of the gate and the lower end opening of the hopper in a stepwise manner in accordance with an increase in the weight of the sand measured by a scale.