Patent ID: 8043018

Claim:
A ring binder mechanism comprising: an elongate housing; first and second hinge plates supported by the housing for pivoting motion relative to the housing; rings, each including a first ring member and a second ring member, the first ring member being mounted on the 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 first and second ring members form a substantially continuous closed loop, and in the open position the first and second ring members form a discontinuous open loop; a pin secured to the housing; an actuating lever mounted on the pin for pivoting movement relative to the housing from a first position to a second position to open the rings; a travel bar operatively connected to the actuator so the pivoting movement of the actuator produces longitudinal movement of the travel bar relative to the hinge plates; a blocking element secured to the travel bar for conjoint movement with the travel bar between a locking position in which the blocking element blocks pivoting movement of the hinge plates to open the rings and a non-locking position in which the blocking element does not block pivoting movement of the hinge plates to open the rings; and a torsion spring received on the pin and positioned to bias the actuating lever to its first position.