Ring binder

A loose-leaf binding mechanism, of the type affixed to covers and a backbone structure, comprising:

• a housing adapted to be affixed to a backbone structure and having an upper wall extending the length of said housing and spaced apart from the backbone structure;
• a pair of hinge plates, each hinge plate pivotally coupled to said housing for movement between a first position with said hinge plates positioned in proximity to said housing and a second position with said hinge plates positioned distally from said housing;
• ring binding means having two opposing portions, each of said opposing portions affixed to opposite hinge plates in cooperating relationship to open and close with the movement of said hinge plates;
• control bar means slideably affixed to said housing, moveable between a first control bar position and a second control bar position, said control bar means further including cam means, said cam means positioned to engage said hinge plates for applying a force in one direction to move said hinge plates toward said housing as said control bar means is moved to said first position, and positioned to engage said hinge plates for applying a force in the opposite direction to move said hinge plates away from said housing as said control bar means is moved to said second position, said control bar means having a slotted opening aligned lengthwise corresponding to the movement of said control bar means;
• and
• control bar affixing means extending through said slotted opening in said control bar means and suspending said control bar means from said upper wall of said housing for sliding movement therealong between said control bar positions whereby said control bar works against said upper wall of said housing through said control bar affixing means and independent of said backbone structure in applying forces to said hinge plates.

A loose-leaf binding mechanism, of the type affixed to covers and a backbone structure, comprising:

• a housing, adapted to be affixed to a backbone structure having a curved surface extending axially along the length of said housing;
• a pair of hinge plates, each hinge plate pivotally coupled to said housing for movement between a first position with said hinge plates positioned in proximity to said housing and a second position with said hinge plates positioned distally from said housing;
• ring binding means having two opposing portions, each of said opposing portions affixed to opposite hinge plates in cooperating relationship to open and close with the movement of said hinge plates;
• control bar means slideably affixed to said housing, moveable between a first control bar position and a second control bar position, said control bar means further including cam means, said cam means positioned to engage said hinge plates to move said hinge plates toward said housing as said control bar means is moved to said first position, and positioned to engage said hinge plates to move said hinge plates away from said housing as said control bar means is moved to said second position, said cam means including slightly inclined cam surfaces which exert gradual forces upon said hinge plates, said control bar means having a slotted opening aligned lengthwise corresponding to the movement of said control bar means;
• control bar affixing means extending through said slotted opening in said control bar means and slideably affixing said control bar means to said housing for movement independent of said backbone structure;
• and
• control bar locking means including a plurality of parallel extending grooves on said control bar means and tongue means on said housing affixed in cooperating relationship with said slightly inclined cam surfaces on said control bar means and housing for locking said control bar means in a selected one of several fixed positions to locate said cam means relative to said hinge plates to lock said ring binding means with a selected one of several closing forces.