Abstract: A rotary trimmer apparatus and signature trimming method are provided that enable operators to set a gap spacing between a rotating knife and an anvil at different predetermined sizes in an easy and accurate manner. The operator chooses the optimum knife/anvil spacing that produces a scissors-like cutting action on the particular type of signatures being trim cut and which does not cause premature knife dulling. The selected knife/anvil spacing is readily reproducable for future runs with the same operating conditions. This is true regardless of changes in the knife thickness as can be created by sharpening thereof, or knife replacement. For this purpose, a user operated control assembly including a control knob and calibrated indexer are provided. To keep the knife/anvil spacing at the set size during trim cutting operations, a temperature control system is employed that keeps axial expansion of the knife spindle shaft from reducing the gap size.

Abstract: A rotary trimmer apparatus and signature trimming method are provided that enable operators to set a gap spacing between a rotating knife and an anvil at different predetermined sizes in an easy and accurate manner. The operator chooses the optimum knife/anvil spacing that produces a scissors-like cutting action on the particular type of signatures being trim cut and which does not cause premature knife dulling. The selected knife/anvil spacing is readily reproducable for future runs with the same operating conditions. This is true regardless of changes in the knife thickness as can be created by sharpening thereof, or knife replacement. For this purpose, a user operated control assembly including a control knob and calibrated indexer are provided. To keep the knife/anvil spacing at the set size during trim cutting operations, a temperature control system is employed that keeps axial expansion of the knife spindle shaft from reducing the gap size.