A three-ring binder has an actuator crank which closes the rings against the bias of a leaf spring. The crank is turned by means of a lever having a roller thereon that engages a throw of the crank. The roller is arranged on the lever so that it goes past center and locks the rings closed when the lever is fully depressed. Each of the throws of the crank may have its own actuating roller, in which case all the rollers are linked together so as to move in unison.
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