Device for producing thread-stitched book blocks

摘要

A device for producing thread-stitched book blocks from a stack of signatures are arranged flat one on top of the other and are stitched together by stitched seams formed at right angles to the folds by a binding thread passed repeatedly in double strands through the folds of the signatures. The device has a first stitching needle that inserts the binding thread and a second stitching needle that draws the binding thread through the fold from the inside. A punch needle, which passes through the fold from the inside edge to form a punched hole, is arranged opposite the first and second stitching needles, each of which forms a stitched seam. The section of the needle that is used to pierce a fold has a polygonal cross-sectional shape.