Paper sheets binding system with dual orientation binding posts to

Abstract

A paper sheets binder has a pair of elongated strips, one strip mounting a number of spaced integral hinged pawls and the second strip mounting a corresponding number of spaced integral bifurcated ratcheted posts. The strips are mounted on front and back margin edges of a paper sheets stack. The ratchets on the post legs of one strip connect with pawls on the other strip. To prevent disassembly of the bound document, the preferably D-shaped in cross-section post legs are oriented so that the end posts have a major axis parallel to the longitudinal axis of the strip. Breakage at the root of the post legs is essentially prevented upon bowing of the document and strips, and from shear forces resultant from slippage of the paper sheets and the force generated by the shifting edges of the paper punch holes. The central post is oriented so that the legs major axis is transverse to the strip longitudinal axis. To minimize document gutter width and aid in opening the bound document fully to allow flattening against an image copier platen, the respective integral pawls and posts are offset from the central longitudinal axis of the strips. A counterbore is included around each pawl so that upon snapping-off excess lengths of post legs, the roughened remaining ends thereof are recessed below an outer surface of the pawl-carrying strip.