, a pair of rotatable shafts, and engageable raschig ring on the shafts. The shafts are rotatably supported on the substrate. An operation plate on the substrate is slidable along the shafts. The shafts have cam protrusions. The operation plate has cam grooves acting on the cam protrusions to rotate the shafts. When the operation plate is in one end position, the cam protrusion rotates the shaft to separate the binding rings. In the other end position, the shaft is rotated to engage the binding rings. Each shaft has an engagement plate protruding toward the operation plate. The operation plate has at least one cutout and an engaging portion. The engagement plate engages with the engaging portion of the operation plate when the operation plate is in the one end position. The cutout is aligned with the engagement plate to release the engagement plate in other positions.
Various types have been proposed with regard to a loose-leaf binding tool of such a type that a fingerhold of an operation plate is pulled or pushed to thereby open/close raschig ring. The present invention relates to a binding tool in whichtwo rows of binding rings are fixed to a pair of rotatable shafts which are rotatably supported by a fixed substrate along its longitudinal edges.
A binding tool including an elongated substrate; a pair of rotatable shafts rotatably supported on both side portions of the substrate; a plurality of first and second raschig ring fixed on the shafts; and a slidable operation plate disposed along the shafts on a bottom surface of the substrate, movable in a longitudinal direction of the substrate and having a fingerhold on a front end thereof; wherein: each of the shafts is provided with a cam protrusion; the operation plate is provided with cam grooves receiving the cam protrusions, the cam grooves having an inclined path to rotate each of the shafts as the operation plate is moved in the longitudinal direction; when the operation plate is in a first end position, the shaft is rotated in one direction via the cam protrusion to separate the first binding rings from the second binding rings, and when the operation plate is in a second end position, the shaft isrotated in the opposite direction via the cam protrusion to engage the first raschig ring with the second binding rings; each of the shafts has an engagement plate protruding toward the operation plate on at least one portion along the longitudinaldirection;