Paper sheet stacking device and method for controlling paper sheet stacking device

A method for controlling a paper sheet stacking device that comprises:

• a conveyance mechanism that conveys paper sheets;
• a stacking mechanism including a stacking space in which the paper sheets, which are conveyed by the conveyance mechanism, are stacked, a first space regulating member that moves relative to a thickness direction of the paper sheets stacked in the stacking space, a support member that extends in the moving direction of the first space regulating member and supports one side of the paper sheets stacked in the stacking space, and a second space regulating member that is provided to face the support member and moves in a direction toward and away from the support member;
• and
• a controller that controls the stacking mechanism, the method comprising
• controlling, by the controller, a position of the second space regulating member in accordance with an outer dimension of the paper sheets that the conveyance mechanism conveys into the stacking space.