Patent ID: 7549817

Claim:
A ring binder mechanism for retaining loose-leaf pages, the mechanism comprising: a housing having longitudinal ends; hinge plates supported by the housing for pivoting motion about a pivot axis relative to the housing; rings for holding loose-leaf pages, each ring including a first ring member mounted on a first hinge plate and moveable with the pivoting motion of the first hinge plate, each ring further including a second ring member, the first ring member being movable relative to the second ring member so that in a closed position the two ring members form a substantially continuous, closed loop for allowing loose-leaf pages retained by the rings to be moved along the rings from one ring member to the other, and in an open position the two ring members form a discontinuous, open loop for adding or removing loose-leaf pages from the rings; a control structure supported by the housing and movable relative to the housing, the control structure comprising a travel bar and a locking element movable in translation relative to both the housing and the hinge plates, the control structure being disposed for blocking the pivoting motion of the hinge plates in a locking position when the ring members are in the closed position; and a coil spring including a first end connected to the travel bar between two ends of the travel bar, the coil spring biasing the travel bar to a position toward one longitudinal end of the housing corresponding with the locking position.