Method and apparatus for forming multi-layer coils from substantially flat, flexible products, especially printed products, arriving in imbricated product formation

摘要

Before winding-up the printed products arriving in imbricated product formation, the thickness of the imbricated product formation travelling toward a winding mandrel, respectively toward a product coil or package forming thereupon, is regulated to a prescribed value. This is effected by spreading or compacting the printed products within the imbricated product formation. For this purpose a first conveyor device is driven at higher or lower speed than a second preceding conveyor device. The imbricated product formation of prescribed thickness is wound-up upon the winding mandrel together with a winding strap maintained under tension which always lies upon the outer side of the coil layer being formed. By regulating the thickness of the imbricated product formation to be wound-up so as to have a prescribed value which remains essentially constant throughout the winding-up procedure, it is possible to form product coils of essentially constant diameter with a prescribed constant length of winding strap independently of the thickness of the arriving printed products.