Adjustable buckle chute folding machine

A buckle chute having a front side, a back side, a first lateral side and a second lateral side for use in a folding apparatus having a first driving mechanism and second driving mechanism for folding at least one sheet of paper having first and second lateral edges defining a width into a folded piece of the same width, the first and the second lateral edges adjacent the first and second lateral sides of the buckle chute, said buckle chute disposed between the first driving mechanism and the second driving mechanism, said buckle chute comprising:

• an upper guide and a lower guide for forming a channel having an entry point on the front side of the turn chute adjacent to the first driving mechanism;
• a stop, disposed in the channel between the front side and the back side at a separation length from the entry point, for stopping a leading edge of said at least one sheet or the folded piece entering the channel from advancing further into the channel toward the back side, so as to cause said at least one sheet or the folded piece to buckle at a locality thereof outside the entry point of the turn chute toward the second driving mechanism for forming a folded edge at the buckled locality by the second driving mechanism as the first driving mechanism continues driving said at least one sheet or the folded piece toward the buckle chute;
• and
• an adjustment mechanism, mechanically engaged with the stop, for moving the stop toward the front side or the back side for adjusting the separation length, wherein the adjustment mechanism comprises a screw system threadably engaged with the stop for relocating the stop, relative to the entry point of the channel
• wherein the stop has a first end and a second end adjacent to the first lateral side and the second lateral side of the buckle chute, and the screw system comprises a first lead screw disposed near the first lateral side of the buckle chute for operatively engaging with the first end of the stop, and a second lead screw disposed near the second lateral side of the buckle chute for operatively engaging with the second end of the stop, and wherein the first and second lead screws are mechanically linked to each other such that the first and second lead screws can be caused to turn simultaneously for moving both first and second ends of the stop, relatively to the entry point of the channel, by a substantially equal distance for adjusting the separation length.