Locking booster ring binder mechanism

摘要

A loose-leaf binder mechanism has a housing containing a pair of pivotally mounted hinge plates each carrying a series of spaced prongs. The hinge plates toggle between open and closed positions under the control of an actuating lever. One portion of the lever is selectively moveable into a wedged-in position between the housing and hinge plates to lock the prongs in closed position. The lever is specially constructed so that it can be moved while wedged between the housing and hinge plates to a safety locking position such that any point of contact between the lever portion and the housing is advantageously disposed longitudinally inward of any point of contact between said one portion and the hinge plates, and so that it cannot be moved inward past the safety-lock position out of the wedged-in configuration between the housing and hinge plates.