This application claims the priority of European Patent Application No. 07405252.3, filed on Aug. 27, 2007, the subject matter of which is incorporated herein by reference in its entirety.
The invention relates to a method for producing adhesive-bound book blocks composed of gathered signatures. With this method, the individual signatures forming a non-bound book block are supplied to an opened conveying clamp for an adhesive binder while positioned on their spines in a transfer section and are subsequently held in place by the closed conveying clamp along the flat outer surfaces. The invention furthermore relates to an apparatus for realizing the method.
For an industrial-type production of adhesive-bound printed products, for example magazines, catalogs, paperback books or similar products, printed sheets or signatures are gathered during a first step to form non-bound book blocks. Subsequently, the spinal region of these book blocks is processed, for example by milling, and is then provided with adhesive in a perfect binder, whereupon the book blocks are bound and/or provided with a casing. The position of the printed image on the sheet or the signature is determined in reference to the edges of its spine and generally also in reference to the top edges. Thus, if all signatures of a non-bound book block are aligned with these reference edges, then all pages within a book block are also aligned relative to each other. According to known prior art, signatures positioned inside a conveying channel are gathered and aligned with the aid of circulating conveying elements. A gathering device of this type is disclosed, for example, in European patent document EP 1 726 552 A1. Following the gathering of the signatures, the non-bound book blocks having spine edges that are aligned transverse to the conveying direction are then rotated by 90°, so that the spinal edges are aligned parallel with the conveying direction. In a further step, the non-bound book blocks are positioned upright on the spines, so that their flat sides are perpendicular and, in this position, are inserted from below into the conveying clamps of the perfect binder. A method of this type is disclosed in the applicant's own, European Patent No: EP 1886832. During the complete binding process, the book blocks are clamped into the circulating conveying clamps, wherein their flat sides are positioned perpendicular and parallel to the conveying direction and the spine areas project slightly from the conveying clamps, in a downward direction. The positioning accuracy for the book blocks in the conveying clamps is decisive for the quality of a book.
It is therefore an object of the present invention to be able to supply precisely aligned book blocks composed of loosely gathered signatures to the conveying clamps of a perfect binder.
The above and other objects are accomplished according to the invention by the provision of a method for producing an adhesive-bound book block from gathered signatures, which according to one embodiment includes: supplying a non-bound book block composed of gathered signatures which are respectively positioned on their spines to an opened conveying clamp in a first conveying section of a perfect binder; subsequently closing the conveying clamp and holding the non-bound book block by the closed conveying clamp along the flat outer surfaces of the non-bound book block; releasing the gathered signatures from the conveying clamp in a second conveying section and aligning and guiding the gathered signatures of the non-bound book block; and after the gathered signatures are aligned and guided during the releasing step, and prior to leaving the second conveying section, clamping the signatures in again along the flat outer surfaces by closing the conveying clamp so that the signatures can be transported to a further processing location.
Thus, according to the invention, the signatures gathered to form a book block are aligned in an additional conveying section while no longer clamped in by the conveying clamp but guided by it, and by closing the conveying clamp again prior to leaving the conveying section that is designed for aligning the signatures, such that the signatures are clamped in along the flat outer surface areas for a transport to further processing locations.
These and other features and advantages of the invention will be further understood from the following detailed description with reference to the accompanying drawings, which show in:
By dividing the holding force, which is lower than the clamping force, over several partial areas of the outer surfaces of a book block to ensure a secure transport of the book block 2 from the transfer section 4 to the conveying section 7 and/or the aligning section 13, the signatures 1 are prevented from adhering to each other and the outermost signatures 1 are prevented from adhering to the clamping jaws 17, 19. The conveying clamps 5 are opened and closed with the aid of an opening rail 22, which allows the second clamp part 20 to move counter to the force of the closing spring and which keeps the conveying clamp 5 open by maintaining the necessary opening width W for aligning the signatures 1 of a book block 2. With the aid of a conveying device 11, the non-bound book blocks 2 of gathered signatures 1, which are respectively positioned upright on their spines, are inserted from below into the opened conveying clamps 5 of the perfect binder in a transfer region 10, formed by the conveying device 11 and the transfer section 4. In the region of the transfer section 4, the opening width W is selected such that the non-bound signatures 1 forming the book blocks 2 can be inserted without problem between the clamping jaws 17, 19. For this operation, the holding elements 23 are moved back to the inactive outer end position with the aid of the pullback device 24. The conveying device 11 essentially comprises a plurality of conveying elements 26, provided with grippers 27, which are driven to circulate along a path 25. During the transfer from the conveying device 11 to the opened conveying clamps 5 of the perfect binder, the book blocks are clamped in and/or held along the flat sides 6 by the grippers 27 and are positioned on their spines for being guided on the side by the clamping jaws 17, 19. The conveying elements 26 remain essentially aligned horizontally for this, as shown in
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and that the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.
Number | Date | Country | Kind |
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07405252.3 | Aug 2007 | EP | regional |