Abstract: An apparatus for spiral binding a stack of papers together as a unit. The apparatus includes a coil feeder for feeding a spiral coil into the holes in the stack of papers, a pin extension and retraction mechanism, a coil cutter mechanism, and a paper thickness measuring and sizing mechanism. The spiral binding unit includes an aperture through which a spiral coil is inserted between a feed shaft and a rotatably mounted roller. The roller may be rotated in a pulsed manner. As the coil is inserted, the roller pushes the spiral coil into contact with the feed shaft. As the roller rotates, the coil is guided around a plurality of spiral guides that cause the coil to spiral into the holes in the stack of paper. The guides and any other surfaces which the end of the coil contacts along its path may have chamfered edges. The pin extension and retraction mechanism includes a plurality of curved locator pins that are movable between an extended and a retracted position.

Abstract: An apparatus for spiral binding a stack of papers together as a unit. The apparatus includes a spiral binding unit for feeding a spiral coil into the holes in the stack of papers, a pin extension and retraction mechanism, a coil cutter mechanism, and a paper thickness measuring and sizing mechanism. The spiral binding unit includes an aperture through which a spiral coil is inserted between a feed shaft and a rotatably mounted roller. As the coil is inserted, the roller pushes the spiral coil into contact with the feed shaft. As the roller rotates, the coil is guided around a plurality of spiral guides that cause the coil to spiral into the holes in the stack of paper. The pin extension and retraction mechanism includes a plurality of locator pins that are movable between an extended and a retracted position. In the extended position, the pins extend up through the holes in the stack of papers. The locator pins are mounted on pivotally mourned levers. The levers are in turn rotated by a cam shaft.