Ready lock ring binder mechanism

A ring binder mechanism for retaining loose-leaf pages, the mechanism comprising:

• a housing comprising opposite longitudinally extending edge margins and a central portion located between the edge margins;
• first and second 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 the 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;
• an actuator pivotally mounted on the housing and movable relative to the housing for controlling the pivoting motion of the hinge plates opening and closing the ring members;
• a travel bar moveable longitudinally in the housing by the actuator into position for blocking the pivoting motion of the hinge plates when the ring members are closed, the travel bar having a flat surface facing toward the central portion of the housing;
• wherein the actuator can be moved in a range without actuating corresponding movement of the travel bar.