Loose-leaf binder

Claim 1

A LOOSE-LEAF BINDER COMPRISING A PAIR OF COVER MEMBERS HINGED TO A BACK MEMBER AND ADAPTED TO BE SWUNG TO OPEN AND CLOSED POSITIONS; A PLURALITY OF SPACED APART SUBSTANTIALLY CIRCULAR RETAINING RINGS ADAPTED TO RECEIVE FILLER SHEETS PROVIDED WITH APERTURES AT THEIR INNER MARGINAL EDGES FOR FITTING OVER SAID RINGS; SAID RETAINING RINGS BEING SPLIT AND PORTIONS THEREOF BEING SWINGABLE TOWARD AND AWAY FROM EACH OTHER TO CLOSE OR OPEN THE RINGS; A SHIELD PLATE MOUNTED ON AND SPACED FROM SAID BACK MEMBER TO PROVIDE A CHAMBER ENCLOSING THEREIN RING OPERATING MECHANISMS FOR SUPPORTING SAID RINGS AND FOR OPENING AND CLOSING SAID RINGS; SAID SHIELD PLATE HAVING APERTURES THROUGH WHICH THE RINGS EXTEND WITH A MAJOR PORTION OF THE ARC OF THE CIRCLE OF EACH RING EXPOSED; A CHANNEL-SHAPED MEMBER HAVING ITS WEB SUPERPOSED OVER SAID SHIELD PLATE WITHIN SAID PLURALITY OF CIRCULAR RETAINING RINGS; THE MARGINAL FLANGES OF SAID CHANNEL-SHAPED MEMBER EACH BEING HINGEDLY JOINTED AT ONE EDGE TO SAID WEB AND EACH HAVING AN OPPOSITE EDGE INWARDLY SPACED FROM SAID RINGS; A FLAT SHEET LIFTER MEMBER FULCRUMED AT ONE OF ITS EDGES TO EACH OF SAID OPPOSITE FLANGE EDGES OF SAID CHANNEL-SHAPED MEMBER AND PROVIDED WITH APERTURES FOR FITTING OVER SAID RINGS EXTERIOR OF FILLER SHEETS THEREON, THE INNER EDGES OF SAID APERTURES BEING SPACED FROM SAID FULCRUMS TO MAINTAIN SAID FULCRUMS SPACED INWARD FROM SAID RINGS.