Patent ID: 7758271

Claim:
A ring binder mechanism for retaining loose-leaf pages, the mechanism comprising: a housing having a detent; hinge plates supported by the housing for pivoting motion relative to the housing, at least one of the hinge plates defining a hinge plate opening through the hinge plates; rings for holding loose-leaf pages, each ring including a first ring member and a second ring member, the first ring member being mounted on a first hinge plate and moveable with the pivoting motion of the first hinge plate relative to the second ring member between a closed position and an open position, in the 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 the 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 for causing the pivoting motion of the hinge plates, the control structure comprising a travel bar having an elongated travel bar opening therein, the travel bar being moveable between a first position wherein the rings are closed and locked and a second position; and a spring plate operatively connected to the control structure at a first end and received through the travel bar opening to connect to the detent in the housing at a second end, the spring plate being at least partially aligned with the opening defined by the hinge plate for passing into the opening upon deflection of the spring plate for urging the control structure from said second position toward said first position, the spring plate being located substantially below the travel bar, the travel bar opening being offset lengthwise of the housing from the hinge plate opening in the first and second positions.