This machine applies a corner staple to the paper stack while it is hanging out of the exit. At this time, to prevent the paper stack from dropping to the upper tray, the edge guide [D] comes out of the unit. The edge guide operates as follows:

  1. When a job starts, the upper tray guide plate [A] shifts up.
  2. The edge guide motor [B] drives to push the edge guide [D] out. The edge guide retreats into the machine when the last sheet of a job is output (the edge guide HP sensor [C] detects the edge guide).