Ranking of criteria for prepress processing of newspaper publications

The analysis of scientific publications has revealed the direction of further detailed study of the process of trimming book blocks with a multi-blade tool during their movement along an arc. The reviewed scientific papers do not contain comprehensive recommendations for the design of a multi-blade tool for trimming book blocks during their movement along an arc. There is no substantiation of the geometric parameters of a multi-blade cutting tool for the formation of a wedge-shaped residue of the uncut part of the sheets at the final stage of the book block trimming process.

The design of the cutting tool must ensure high-quality cutting of the main part of the block sheets and cutting of the middle part at the final stage of the cutting cycle. To do this, it is necessary to determine the radius of the average arc of the block trajectory during trimming, which divides the cut plane of book and magazine blocks into two parts of equal area. A mathematical model of trimming book and magazine blocks with a multi-blade cutting tool while moving along an arc is created to determine the radius of the average trajectory of the blocks. The outer and inner cut areas of book and magazine blocks relative to the average trajectory by sets of blades are determined. Using a mathematical model of the trimming process, the radius of the averaged trajectory of the blocks and the areas of the cut of book and magazine blocks external and internal to the averaged trajectory by sets of blades of the cutting tool are determined. The arc of the averaged trajectory of the block divides the cut plane of the book and magazine blocks into two parts of equal area, so the amount of block material removed by the outer and inner blade sets relative to the averaged arc is the same, and thus the work of the cutting forces of both blade sets is also the same. At the same time, the blades of the outer and inner sets of the cutting tool provide uniform support for the uncut part of the block sheets during the trimming cycle, which ensures the quality and accuracy of the trimming operation.

The obtained results of theoretical studies create the prerequisites for the development of a spatial model of the cutting tool in order to confirm the feasibility of the BRI design as one that provides high quality of the cut plane.

Keywords: Average trajectory, cutting area, multi-blade cutting tool, book and magazine block.

doi: 10.32403/0554-4866-2024-1-87-148-155