Method and apparatus for manufacturing book blocks
AssigneeGrapha-Holding AG
InventorsHans Hollenstein, Heinz Botschi, Marcel Stolz
Life of this patent
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Abstract
During manufacture of thread-sewn book blocks (11) from a stack of flat sequentially juxtaposed signatures (3) which are sewn together by way of a double-stranded binding thread (9) which penetrates the folds (4) from the outside and extends in sections along the inside edge of the folds and is pulled out again, the binding thread sections (16, 17) which are inserted by a first sewing needle (5) between the legs (14) of the signatures (3) are captured by a gas jet and conveyed in form of a loop (21) to the adjacent second sewing needle (6) which pulls the loop (21) out of the signature (3) through a return stroke motion using a hook (22).
Claims16
A method for manufacturing thread-sewn book blocks from a stack of flat sequentially juxtaposed signatures which are sewn together with a double-stranded binding thread penetrating the folds of the signature from the outside and extending along the inside edge of the folds and being pulled out of the folds at an exit point, with the help of parallel stitched seams oriented at right angles to the folds, comprising the steps of
- associating with each of the stitched seams a first sewing needle which penetrates a fold with the binding thread from the outside;
- pulling the binding thread out of the fold at the exit point with a second sewing needle;
- providing joining means for joining the binding thread which is guided inseparably in the first sewing needle, with the second sewing needle inside a spread-apart signature;
- capturing by a gas jet a section of the double-stranded binding thread inserted by the first sewing needle between the legs of a signature;
- and
- transferring the section of the double-stranded binding thread to the second sewing needle.
An apparatus for manufacturing thread-sewn book blocks from a stack of flat sequentially juxtaposed signatures which are sewn together with a double-stranded binding thread penetrating the folds of the signature from the outside and extending along the inside edge of the folds and being pulled out of the folds at an exit point, with the help of parallel stitched seams oriented at right angles to the folds, comprising:
- a conveyor for transporting of signatures (3) to a sewing station, including at least one sewing device formed of a first (5) and a second (6) driven sewing needle for forming two stitched seams on the back of a book block, and a saddle-shaped sewing table (30) which can be controllably driven by clock pulses, for conveying the signatures (3) to the sewing device and for carrying out the sewing operation;
- and
- wherein there is disposed inside the sewing table (30) an outlet opening of a gas line (18) connected to a pressure source to produce a gas jet, the outlet opening being oriented towards a section of the binding thread (9) adapted to form an open loop (21) and towards the movement path of the second sewing needle (6).
Dependencies are inferred from the claim text.