Patent ID: 7950866

Claim:
A ring binder mechanism for holding loose-leaf pages, the mechanism comprising: an elongate housing constructed of a polymeric material and having a central portion and lateral sides extending downwardly along either side of the central portion, the housing having a length and being resiliently deformable for applying a spring force; a ring support constructed of metal and disposed between the lateral sides of the polymeric housing and supported thereby for movement relative to the housing, the ring support having a length greater than one half the length of the housing; and a plurality of rings for holding the loose-leaf pages, each ring including a first ring member and a second ring member, the first ring member being mounted on the ring support for movement with the ring support relative to the housing between a closed position and an open position, in the closed position the first and second ring members forming 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 first and second ring members forming a discontinuous, open loop for adding or removing loose-leaf pages from the rings, the housing spring force biasing the ring support toward the open position of the first ring member when it is proximate its open position and biasing the ring support toward the closed position of the first ring member when it is proximate its closed position, the housing spring force being the only spring force applied to the ring support that moves the ring support.