Tractor gear for machine for processing flat printed matter has endless traction mechanism and traction tensioner which keeps pretension of traction mechanism unchanged during displacement of wheel by adjusting traction loop

摘要

The tractor gear which has an endless traction mechanism (36.1), first and second wheels (36.2, 36.3) and a traction tensioner (36.4) is geometrically designed so that during displacement of the second wheel (36.3) by increasing the axial distance (A) in a first instance and reducing the axial distance (A) in a second instance by reducing the loop of the traction tensioner in the first instance and increasing the loop of the tensioner in the second instance the pretension of the traction mechanism remains at least substantially unchanged without a change of position of the tensioner.