Sorter with rotary spirals and guide rails

A sorter comprising:

• a plurality of bin trays arranged in a vertical direction, each bin tray having a specified width and length and adapted for bearing a sheet;
• shifting means for shifting the plurality of bin trays in the vertical direction;
• and
• moving means for moving a bin tray at a predetermined position in said sorter, in a lengthwise direction of the respective bin tray;
• said moving means including disengaging means for disengaging the bin tray from the shifting means;
• said shifting means including:
• a pair of rotatable upstanding cylinders arranged on opposite sides of the plurality of bin trays, each cylinder having a guide surface extending spirally on a surface of the cylinder;
• a pair of pins projecting horizontally from opposite sides of each bin tray and slidable on the guide surface and disengagable therefrom at said position;
• and
• driving means for rotating the pair of cylinders;
• whereby the pins slide on the guide surface in response to rotation of the cylinders so as to shift the plurality of bin trays in the vertical direction.