Abstract: A ring binder includes a base member supporting a plurality of ring members, and an opening mechanism at each end of the base member for opening the plurality of ring members, each opening mechanism including lock means to lock the opening mechanisms in its closed position, the base member comprising a rigid upper structure supporting a pivotable lower structure to which the ring members are mounted, wherein at each end of the binder, the opening mechanism is coupled to and pivotally supported in the lower structure. In another embodiment the opening mechanism has an inbuilt degree of play before before acting to urge the lower structure to close the ring members for ease of operation.

Abstract: A ring binder includes a base member supporting a plurality of ring members, and an opening mechanism at each end of the base member for opening the plurality of ring members, each opening mechanism including lock means to lock the opening mechanisms in its closed position, the base member comprising a rigid upper structure supporting a pivotable lower structure to which the ring members are mounted, wherein at each end of the binder, the opening mechanism is pivotally supported between the lower structure and the upper structure, externally of the lower structure, and internally of the upper structure.