Ricoh D131 Service Manual page 1497

Details
After the last sheet has been pre-stacked, the TE stop pawl [A] lowers and the sheets are
jogged vertically (top to bottom).
Next, with the TE stop pawl pressing down on the trailing edges of the stacked sheets, the
stack [B] is jogged horizontally (front to back).
D454/D615 104 SM