To easily take out a bundle of sheet material stored on a stacker tray.

A bundle of sheet material carried by a carriage gripper 12 is stacked and stored in a stacker tray 116 and the bundle of sheet material is drawn to a transfer direction different from a sheet material carriage direction to the stacker tray 116. A guide part 116b which comprises a recessed part or projected part substantially parallel to transfer direction is disposed in a designated position of the stacker tray 116. Whereby, when the bundle of the sheet material is bound by a binding needle, the binding needle is not caught in the stacker tray 116 and the bundle of sheet material is easily taken out.